Researcher basic information

• 博士（獣医学）, 北海道大学

• https://researchmap.jp/snakayama?lang=en

• https://jglobal.jst.go.jp/detail?JGLOBAL_ID=201201057197575960
• http://tox.vetmed.hokudai.ac.jp/

• 90647629

• 201201057197575960

• 長期慢性暴露
• 低濃度暴露
• 腸内細菌叢
• LA-ICP-MS
• 動物種差
• 歩哨動物
• 汚染源推定
• 同位体比
• 鉛汚染

• Environmental Science/Agriculture Science, Environmental impact assessment
• Environmental Science/Agriculture Science, Chemical substance influence on environment
• Environmental Science/Agriculture Science, Radiation influence
• Environmental Science/Agriculture Science, Landscape science
• Environmental Science/Agriculture Science, Environmental agriculture

• Bachelor's degree program, School of Veterinary Medicine
• Doctoral (PhD) degree program, Graduate School of Veterinary Medicine

Research activity information

• Dec. 2022, 公益財団法人農学会, 第21日本農学進歩賞
  アフリカにおける人と動物の環境金属汚染の解明と対策法の開発
• Jul. 2018, 日本毒性学会, 第45回 日本毒性学会学術年会 優秀研究発表賞
  ザンビア共和国カブウェ鉱床地域における鉛汚染問題：10年間の研究結果と今後の課題
  中山翔太
• Mar. 2012, 日本学術振興会, 第２回（平成23年度）日本学術振興会育志賞
  アフリカの野生生物における環境汚染物質の毒性影響評価
  中山翔太
• Jul. 2011, 日本環境化学会, 20th Symposium on Environmental Chemistry, Student Presentation Award
  Metal concentration and stable isotope ratio analysis (d13C and d15N) in water, sediment and fish from Lake Itezhi-tezhi, Zambia
  Shouta NAKAYAMA

• Micro- and mesoplastic contaminants in marine diving ducks: A first assessments from the coast of Japan.
  Yurika Tokunaga; Naoko Yoshizato; Hideshige Takada; Kosuke Tanaka; Kazuhiko Hirata; Sachiko Moriguchi; Takuya Kato; Yoshinori Ikenaka; Shouta M M Nakayama; Shin-Ichi Hayama; Mayumi Ishizuka
  Marine pollution bulletin, 226, 119373, 119373, May 2026, [International Magazine]
  English, Scientific journal, Plastic pollution poses a serious threat to seabirds, yet the relationship between plastics and molluscivorous species remains severely understudied despite high risk of exposure to plastics in sediments and contaminated prey. As coastal benthic environments are hotspots for plastic contamination, seaducks that dive and forage on mollusks (predominantly benthic bivalves and gastropods) in coastal habitats may be particularly vulnerable. This study presents the first assessment of plastic contamination in two molluscivorous seaducks: Black Scoters (Melanitta americana) and Stejneger's Scoters (M. stejnegeri), which winter along Japan's Pacific coast. Gizzard samples from 10 individuals were analyzed using Fourier transform infrared spectroscopy after alkaline and acid digestion and density separation, providing an initial assessment of plastic contamination. Microplastics were found in all samples, with a median of 240 particles per bird, corresponding to 7.3 particles g-1 (gizzard content). Diet and foraging habitat may drive this high plastic burden. 99.8% of the plastics were < 200 μm (a size class not considered during previous seaduck studies) and were predominantly fragments (>98% in both species) which may originate from contaminated prey. Polyethylene and polypropylene were the most common polymers identified, accounting for 78.1% of all detected plastics. However, the presence of two polystyrene microplastic pellets and one polystyrene mesoplastic sphere is a unique finding, which is potentially linked to the scoters' foraging behavior. Given seaducks' high exposure and potential health risks associated with their feeding ecology, as well as anatomical and physiological traits, further research should include quantification of nanoplastics in tissues due to the greater toxicological risks involved.
• Maternal blood lead levels and proximity to legacy mining contamination in Kabwe, Zambia: socioeconomic disparities and potential implications on fetal health.
  Doreen Sakala; John Yabe; Isaac Fwemba; Nosiku Munyinda; Nasson Nathan Tembo; Madalitso Tembo; Hikabasa Halwiindi; Mayumi Ishizuka; Shouta M M Nakayama
  Environmental science and pollution research international, 28 Apr. 2026, [International Magazine]
  English, Scientific journal, Legacy lead (Pb) contamination from a century-long Pb-Zn mining operation (1906-1994) continues to pose severe environmental health threats in Kabwe, Zambia, one of the world's most polluted sites. While elevated blood lead levels (BLLs) in children are well-documented, maternal exposure remains understudied despite its critical implications for fetal development. We conducted a cross-sectional biomonitoring study among 510 pregnant women across four townships in Kabwe (Makululu, Kasanda, Katondo, and Mahatma Gandhi), stratified by proximity to the former mine (1.5-4.5 km). Sociodemographic and clinical data were collected utilizing a structured questionnaire. Venous blood samples were analyzed for Pb using graphite furnace atomic absorption spectrophotometry (GFAAS), with rigorous quality control (recovery: 92.3-95.1%; MDL: 0.012 µg/dL). Maternal BLLs varied significantly by township (p < 0.001): median BLLs were highest in Makululu (6.5 µg/dL; 84.4% elevated), followed by Kasanda (3.4 µg/dL; 48.1%), and lowest in Katondo (1.8 µg/dL; 10.0%) and Mahatma Gandhi (1.6 µg/dL; 8.8%). Overall, 43.7% of women exceeded the reference level of 3.5 µg/dL, disproportionately affecting those in the informal settlements near the mine waste. Elevated BLLs were significantly associated with longer years of stay in the area (p = 0.007), unemployment (p < 0.001), smoking (p = 0.021), lower BMI (p = 0.023), and higher gravidity (p < 0.001), reflecting intersecting environmental, biological and socioeconomic vulnerabilities. Maternal Pb exposure in Kabwe remains alarmingly high, especially in mining-proximal, low-resource communities, underscoring a critical environmental injustice. Given potential for Pb to cross the placenta and documented links to negative birth outcomes, urgent interventions, including regular maternal screening and policy reform, are needed to potentially protect the health of the unborn baby and break cycles of intergenerational toxicity.
• Reductive dominance and limited cytochrome P450 activity in neonicotinoid metabolism by elephant liver microsomes.
  Kanami Watanabe; Kraisiri Khidkhan; Aksorn Saengtienchai; Chaleamchat Somgrid; Patcharapa Towiboon; Taweepoke Angkawanish; Warangkhana Langkaphin; Kittikul Namwongprom; Narueporn Kittisirik; Yared B Yohannes; Yoshinori Ikenaka; Shouta Mm Nakayama; Mayumi Ishizuka
  The Journal of veterinary medical science, 88, 4, 607, 613, 02 Apr. 2026, [Domestic magazines]
  English, Scientific journal, Neonicotinoids (NNs) are commonly used insecticides; however, their biotransformation in wild mammals remains poorly understood. Asian elephants, which are declining in numbers, may be vulnerable to these chemicals. In this study, we examined the liver metabolism of four major NNs: acetamiprid, imidacloprid, thiamethoxam, and clothianidin, using elephant liver microsomes. Metabolite profiling and targeted analysis were conducted with liquid chromatography quadrupole time-of-flight mass spectrometry and liquid chromatography tandem mass spectrometer, respectively. Results indicated that elephants mainly metabolize these NNs via reductive pathways, suggesting the involvement of nitroreductase-like enzymes. Conversely, cytochrome P450-mediated oxidation may be limited; however, the roles of other enzymatic or microbial systems cannot be ruled out. These findings provide insights into xenobiotic metabolism in elephants, helping evaluate their toxicological vulnerability and supporting conservation efforts and risk assessments.
• Corrigendum to "Intergenerational sex-specific transcriptomic alterations in gonads of mice after parental lead exposure" [Reprod. Toxicol. 140 (2026) 109154].
  Nelly Banda; Kanami Watanabe; John Yabe; Rio Doya; Kaampwe Muzandu; Yared Beyene Yohannes; Andrew Kataba; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta M M Nakayama
  Reproductive toxicology (Elmsford, N.Y.), 141, 109197, 109197, Apr. 2026, [International Magazine]
  English
• Intergenerational sex-specific transcriptomic alterations in gonads of mice after parental lead exposure.
  Nelly Banda; Kanami Watanabe; John Yabe; Rio Doya; Yared Beyene Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta M M Nakayama
  Reproductive toxicology (Elmsford, N.Y.), 140, 109154, 109154, Mar. 2026, [International Magazine]
  English, Scientific journal, Lead (Pb) exposure is known to influence gene expression across multiple tissues, potentially affecting germline biology and offspring development. This study investigated transcriptomic alterations in the gonads of F1 mice following four weeks of parental exposure to Pb‑contaminated soil. After exposure, breeding generated four experimental groups: ① exposed dams with unexposed sires, ② exposed sires with unexposed dams, ③both parents exposed, and ④ unexposed controls. Testes and ovaries were collected from 9‑week‑old offspring, and RNA sequencing was performed using Qiagen CLC Genomics Workbench to characterise transcriptional changes. Principal component analysis revealed distinct transcriptomic profiles in Groups 1-3 relative to controls, indicating that parental Pb exposure, whether maternal, paternal, or combined, shaped offspring gonadal gene expression. Heatmap clustering showed partial overlap between Male Group 3 and controls, although unique expression features remained evident. All exposed groups exhibited reduced overall transcript abundance when compared to controls. Males with maternal Pb exposure displayed the highest number of differentially expressed genes (DEGs), with gene ontology analysis highlighting alterations in immune‑related and enzymatic pathways. In contrast, males with both maternal and paternal exposure showed the fewest DEGs, though a greater proportion were located on the Y chromosome. These sex‑specific transcriptional patterns, particularly those observed in the offspring of exposed sires, suggest that Pb‑related molecular effects may arise independently of direct maternal transfer. While the underlying mechanisms remain uncertain, the findings raise the possibility that some effects could be transmitted through heritable pathways.
• Exploring the intricacies of indoor dust pollution from neonicotinoid insecticides and its human health impacts: An exemplar from eleven agricultural communities in Ghana, West Africa.
  Collins Nimako; Osei Akoto; Nathaniel Boadi; Prince Ofori; Yared B Yohannes; Shouta M M Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka
  Journal of hazardous materials, 500, 140172, 140172, 05 Dec. 2025, [International Magazine]
  English, Scientific journal
• Forensic detection and quantification of methomyl in animal stomach contents using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) and liquid Chromatography tandem mass spectrometry (LC-MS/MS) in Japan.
  Yared Beyene Yohannes; Aki Tanaka; Yuko Kihara; Tsuyoshi Tajima; Shouta Nakayama; Collins Nimako; Yoshinori Ikenaka; Mayumi Ishizuka
  The Journal of veterinary medical science, 87, 12, 1494, 1498, 03 Dec. 2025, [Domestic magazines]
  English, Scientific journal, Pesticide poisoning in animals is a rising forensic issue due to widespread chemical use. This study analyzed stomach contents from 44 deceased animals (domestic and wild) in Japan using liquid chromatography quadrupole time-of-flight mass spectrometry (LC-Q-TOF/MS) for non-targeted screening and liquid Chromatography tandem mass spectrometry (LC-MS/MS) for quantification after Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) extraction. Non-target screening detected multiple pesticide classes, with carbamates and herbicides being the most prevalent. Methomyl was identified in 29 cases (65.9%), with concentrations up to 157 mg/kg in cats, 75 mg/kg in a civet, and 30 mg/kg in a dog, exceeding the oral LD50 of methomyl in dogs (10 mg/kg) and cats (estimated to be similar). These findings suggest acute poisoning and possible intentional misuse. The toxicological significance of methomyl highlights the need for stricter regulations, better monitoring, and increased public awareness to prevent further animal poisonings.
• Evaluation of ascorbic acid as an intervention of metal toxicity in dogs in Kabwe district.
  Nelly Banda; Mahongo Selwa; Rio Doya; Nyein Chan Soe; Andrew Kataba; John Yabe; Golden Zyambo; Kaampwe Muzandu; Yared Beyene Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta Mm Nakayama
  Veterinary and animal science, 30, 100519, 100519, Dec. 2025, [International Magazine]
  English, Scientific journal
• Significant reduction of blood and tissue lead and cadmium concentrations in free-range and broiler chickens through soil remediation with biochar, phosphates, and calcined dolomite: Implications for public health and food safety
  Madalitso Tembo; Andrew Kataba; Nyein Chan Soe; Rio Doya; Richard Musonda; Golden Zyambo; Yoshinori Ikenaka; John Yabe; Kaampwe Muzandu; Mayumi Ishizuka; Shouta M. M. Nakayama
  JOURNAL OF HAZARDOUS MATERIALS ADVANCES, 20, Nov. 2025
  English, Scientific journal
• Development of a silica gel chromatography-based cleanup method for quantification of polystyrene nanoplastics in tissue samples via pyrolysis-GC/MS
  Yurika Tokunaga; Kosuke Tanaka; Go Suzuki; Nami Shimizu; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka
  JOURNAL OF HAZARDOUS MATERIALS LETTERS, 6, Nov. 2025
  English, Scientific journal
• Risk assessment of polycyclic aromatic hydrocarbons in airborne particulates of Ulaanbaatar City, Mongolia
  Javzandolgor Tserendorj; Jajinjav Yondonjamts; Bolortuya Damdinsuren; Shagjjamba Dagva; Bayanjargal Unenbat; Sukhbaatar Batchuluun; Yared Beyene; Shouta M. M. Nakayama; Mayumi Ishizuka; Chinzorig Radnaabazar; Yoshinori Ikenaka; Munkhbat Byambajav
  AIR QUALITY ATMOSPHERE AND HEALTH, 28 Oct. 2025
  English, Scientific journal
• Lead Bullet Burden: Widespread Lead Exposure in Wild Carnivores and Unseen Consequences of Feeding Lead-Shot Meat to Captive Cheetahs (Acinonyx jubatus).
  Catherine Hauw; Laurie Marker; John Yabe; María Díez-León; Niall McCann; Gerhard Iiputa; Mark Jago; Esther Mukete-Hilundutah; Trevor Nzehengwa; Nelly Banda; Shouta M M Nakayama; Mayumi Ishizuka; Utarera Katjavivi; Jacqueline Ehrlich; Marc Humphries; Anne Schmidt-Küntzel
  Journal of wildlife diseases, 61, 4, 1038, 1049, 01 Oct. 2025, [International Magazine]
  English, Scientific journal, Lead (Pb) exposure is a global concern because of its harmful effects on the environment, animals, and humans. Although research on Pb poisoning in humans and avian species is extensive, similar literature on mammalian carnivores is limited. Only two reports of suspected Pb poisoning in captive cheetahs (Acinonyx jubatus) exist, and none in wild cheetahs. We quantified cumulative life exposure to Pb in 62 cheetahs (33 males, 29 females) and 11 (unknown sex) leopards (Panthera pardus). Cheetahs were grouped according to time spent in captivity: wild (>10% of life in the wild) and captive (10-100% of life in captivity); all leopards were wild. Bone Pb concentration (BLC) was measured in tibias to assess the effects of time in captivity, age, and sex on Pb exposure. Lead was detected in all cheetah and leopard tibias. Mean BLC was 1.11±1.92 mg/kg for all cheetahs, with a significantly higher mean in captive (1.57±2.25 mg/kg) versus wild (0.27±0.39 mg/kg) cheetahs. Time in captivity had a significant effect on BLC, with BLC increasing with years spent in human care. Wild leopards had a higher BLC than wild cheetahs, with a mean BLC of 1.02±1.56 mg/kg. Higher BLC in captive than wild cheetahs was attributed to Pb exposure from the ammunition used to shoot ungulates for their diet. Increased exposure in wild leopards might be attributable to opportunistic scavenging, a behavior not typically seen in wild cheetahs. This study highlights the need for non-Pb ammunition options in support of conservation, animal welfare, and ultimately human health.
• Evaluation of Neurotoxicity of Neonicotinoid Insecticides Using Lipidomics.
  Tomoya Koike; Anri Hirai; Kei Nomiyama; Akihumi Eguchi; Nobuhiko Hoshi; Tetsushi Hirano; Collins Nimako; Yared Beyene Yohannes; Mai Tamba; Shouta M M Nakayama; Mayumi Ishizuka; Yoshinori Ikenaka
  Environmental toxicology and chemistry, 44, 11, 3212, 3224, 09 Aug. 2025, [International Magazine]
  English, Scientific journal, Neonicotinoid (NN) pesticides are widely used globally, but recent studies suggest that even non-toxic doses can induce anxiety-like behaviors and alter brain monoamine neurotransmitter levels in mice. Current neurotoxicity assays may fail to detect subtle toxic effects, such as higher brain function abnormalities caused by small molecule disruptions. These findings highlight the need for highly sensitive and reproducible neurotoxicity testing methods. The brain, a lipid-rich organ, relies on lipids for various functions, and disturbances in lipid homeostasis are linked to numerous diseases. This study uses lipidomics to analyze the cerebral cortex of mice exposed to the NN acetamiprid (ACE), aiming to identify lipid biomarkers of neurotoxicity. Thirty 12-week-old male C57BL/6J mice were randomly divided into control (0 mg/kg), low dose (65 mg/kg), and high dose (130 mg/kg) groups, with 10 mice in each group. Mice were euthanized, and cerebral cortex samples were collected 30 minutes after oral ACE administration. Lipids were extracted and analyzed using Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry (LC/Q-TOF/MS). A total of 358 lipids were annotated. Fifteen lipids exhibited a fold change > 2.0 and significant differences between control and high-dose groups, with an AUC ≥ 0.900 in ROC analysis. Increased levels of seven fatty acids (e.g., palmitic acid) and five Fatty Acyl Esters of Hydroxy Fatty Acids (e.g., FAHFA 22:6_22:5) were observed, suggesting roles in neurodegenerative diseases and inflammation. These findings identify a promising lipid biomarker linked to NN-induced neurotoxicity and contribute to detecting neurotoxic effects from acute exposure to such substances.
• Anthropogenic Activities Elevate Heavy Metals Levels in Soil and Tree Bark; A Case Study of Lower Zambezi and Mosi-Oa-Tunya National Parks.
  Nelly Banda; Kanami Watanabe; Rio Doya; Nyein Chan Soe; Andrew Kataba; John Yabe; Golden Zyambo; Kaampwe Muzandu; Yared Beyene Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta M M Nakayama
  Archives of environmental contamination and toxicology, 89, 2, 180, 194, 04 Aug. 2025, [International Magazine]
  English, Scientific journal, The impact of various human activities on protected environments remains a significant concern. Mining for ores is crucial in many aspects of society. To achieve global decarbonisation, more metals are required, which will lead to increased worldwide metal exploration and mining. Zambia is primarily a mining country and has expanded exploration into protected lands (national parks). The effects of this exploration on these protected areas is ongoing. This study aimed to establish baseline data for monitoring metal pollution in the Lower Zambezi National Park before mining commenced. It also evaluated whether tourism influenced metal pollution in national parks and how these metals and metalloids correlate within tree bark and soils. To accomplish this, soil and Acacia tree bark samples were collected from Lower Zambezi National Park and Mosi-Oa-Tunya National Park. Arsenic (As), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) were analysed in this study. The concentrations of metals and metalloids were higher in areas with vehicular traffic and mining activity in the national parks, which may directly impact the biosystems in those areas. Maximum levels of metals in soil in these areas were as follows: As 40.8 mg/kg, Cd 0.879 mg/kg, Cr 241 mg/kg, Hg 1.1 mg/kg, Pb 211 mg/kg, and Zn 1285 mg/kg. When compared to areas of lower anthropogenic activities, differences in metal concentrations were up to 1000-fold. These changes can potentially affect the adaptation of wildlife to various stressors, especially as we are facing global climate change.
• Understanding Pb contamination in wild mammals and birds and examining the potential contamination related to ammunition in Japan.
  Nana Ushine; Mizuki Maruyama; Emmanuel Temiotan Ogbomida; Shouta Mm Nakayama; Mayumi Ishizuka; Takuya Kato; Shin-Ichi Hayama
  The Journal of veterinary medical science, 87, 8, 911, 918, 01 Aug. 2025, [Domestic magazines]
  English, Scientific journal, This study investigates lead (Pb) contamination in wild animals in Japan. Pb is a known environmental toxin that can cause several issues in wildlife. Pb is still used in human society, and among Pb products, ammunition is reported to harm human and animal health. In Japan, few instances of Pb contamination in wild animals have been reported outside Hokkaido. Possible reasons for this include the absence of Pb contamination and insufficient investigation. This study aimed to understand the current state of Pb contamination in Japan and clarify the extent of Pb contamination related to ammunition. Blood lead concentrations (BLLs) were measured in wild birds and mammals from 25 municipalities, and an analysis was conducted based on ammunition-related factors. More than half of the avian and mammalian taxonomic groups were found to exhibit Pb contamination from environmental sources. Overall, this study suggests that Pb contamination is also present in wild birds and mammals living outside Hokkaido, Japan, and highlights the risks of mass mortality during infectious disease outbreaks as well as the potential health hazards of Pb exposure upon their consumption by humans. The results of this study highlight the importance of monitoring Pb contamination, particularly in hunting areas of Japan. Further, it indicates the need to reconsider the use of Pb-based ammunition for protecting the health and welfare of both humans and wildlife.
• Pilot-scale stabilization of toxic metal leachates from zinc plant residues using half-burnt dolomite: implications for remediation at Kabwe legacy mine in Zambia.
  Walubita Mufalo; Takahiko Arima; Toshifumi Igarashi; Mayumi Ito; Tsutomu Sato; Shingo Tomiyama; Imasiku Nyambe; Marthias Silwamba; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  Environmental geochemistry and health, 47, 7, 271, 271, 16 Jun. 2025, [International Magazine]
  English, Scientific journal, Stabilizing toxic elements in mine wastes is a practical strategy for countermeasures against improper disposal. Kabwe, Zambia, one of Africa's most lead (Pb)-polluted cities, faces severe contamination from historic zinc plant residues (ZPRs). This study validates the chemical stabilization of Pb and zinc (Zn) in ZPRs using half-burnt dolomite (HbD) in four embankments, two of which were treated with 10% HbD. The embankments were constructed with/without covering soil and a bottom adsorption layer containing soil with HbD (pilot-scale experiments). Five years after construction, batch experiments were conducted to evaluate the leaching behavior of Pb, Zn, and other coexisting ions from the embankments. Mechanisms of stabilization were investigated via surface binding characterization, mineralogical/elemental analysis, sequential extraction, and thermodynamic modeling of the leachates. The ZPRs were mainly composed of anglesite (PbSO₄), gypsum (CaSO₄·2H₂O) and quartz (SiO₂), with elevated Pb and Zn contents ranging from 55,700 to 73,800 mg/kg and 16,500 to 25,300 mg/kg, respectively. Untreated-ZPRs indicated that Zn leaching was driven by the dissolution of soluble Zn-sulfates in mildly acidic conditions, whereas Pb remained immobile due to its association as PbSO₄. In ZPRs-HbD-treated, stabilization of Pb and Zn was facilitated by the decrease in their exchangeable phases and enhanced incorporation into stable carbonate phases, along with binding with Fe-oxyhydroxides, confirmed by X-ray photoelectron spectroscopy. Pilot-scale experiments demonstrated that the bottom soil adsorption layer could effectively sequester leached Pb and Zn from untreated-ZPRs by stabilizing them in the soil matrix-carbonate and Fe-oxyhydroxide phases. Furthermore, the results suggest that a soil cover could form a protective barrier for oral ingestion-induced bioaccessible Pb and Zn in the stabilized residues. Given the extent of legacy pollution in Kabwe, this stabilization technique coupled with a soil cover presents a promising solution for ZPRs contamination from legacy mines.
• Lead concentration in blood of Asian black bears in two areas of Central Japan.
  Koji Yamazaki; Mayumi Ishizuka; Shouta M M Nakayama; Nelly Banda; Shinsuke Koike; Yusuke Goto; Kozo Yamazaki; Yui Nemoto; Boris Fuchs; Jon M Arnemo
  The Science of the total environment, 980, 179555, 179555, 10 Jun. 2025, [International Magazine]
  English, Scientific journal, To measure blood lead level, we collected a total of 88 blood samples from 66 Asian black bears (Ursus thibetanus japonicus) that were live-trapped in two study areas in Japan. In both areas, extensive sika deer (Cervus nippon) and wild boar (Sus scrofa) control programs and sport hunting using lead-based ammunition have been conducted. The area in the Ashio-Nikko Mountains is located near a former copper mine and smelter. The Okutama Mountains are situated in the suburbs of Tokyo, a mega-city with a population of nearly 14 million. In both study areas, the use of leaded gasoline was permitted until 1975 for regular gasoline vehicles. Our analysis revealed that Japanese black bears had higher lead compared to American black bears (U. americanus) and brown bears (U. arctos) in North America. Blood lead concentrations were higher in the Ashio-Nikko Mountains (110.4 ± 38.3 SD μg/L) than in the Okutama Mountains (49.3 ± 46.2 SD μg/L). The blood lead concentrations were particularly high in lactating females compared to most males and females. White blood cell count was decreased with increasing blood lead concentration. The source of lead contamination remains unknown at this time. However, Japanese black bears in our study areas commonly scavenge on large mammals, and lead-based ammunition could constitute a significant portion of the contamination in both areas. In addition, former mining activities could elevate the lead concentrations of bears in the Ashio-Nikko Mountains. Atmospheric lead depositions originating from former leaded gasoline use in Japan and current air pollution from the Asian continent are also potential factors in both areas. Future identification of exposure sources is necessary.
• Assessing the efficacy of phosphate and lime amendments in immobilizing three forms of lead in contaminated soil: An in vivo study on C57/BL6 mice simulating environmentally realistic exposure pathways.
  Nyein Chan Soe; Takashi Fujimori; Kenji Shiota; Rio Doya; Walubita Mufalo; Mayumi Ito; Tsutomu Sato; Toshifumi Igarashi; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta M M Nakayama
  Chemosphere, 374, 144201, 144201, Apr. 2025, [International Magazine]
  English, Scientific journal, Lead (Pb) bioavailability differs depending on the specific Pb species present in the area. Adding organic and inorganic soil amendments can ameliorate the mobility of Pb in the soil. However, there is a scarcity of in vivo studies investigating the impact of these amendments on mammals via environmentally realistic exposure pathways. We evaluated the accumulation of Pb in blood and tissues of mice living on soils spiked with one of three Pb species (hydrocerussite [2PbCO3·Pb(OH)2], lead sulfate [PbSO4], and lead sulfide [PbS]) and compared the efficacy of phosphate (triple super phosphate [TSP] or phosphoric acid) or liming (calcined dolomite) amendments in reducing Pb accumulation from these soils via realistic exposure pathways. The Pb species in the spiked soil were investigated via X-ray absorption near edge structures (XANES) spectroscopy. C57/BL6 mice (six per group) were exposed to both Pb-spiked and amended soils by housing them on the soil for three months and thus simulating realistic exposure pathways. XANES analysis revealed that Pb carbonates were the dominant phase in all Pb-spiked soils. The group exposed to 2PbCO3·Pb(OH)2 had the greatest Pb accumulation in brain, trachea, kidneys, liver, bone, and blood, but not lungs, whereas the PbS-exposed group accumulated more Pb in the lungs. TSP was the most effective chemical stabilizer of the three amendments, facilitating reductions in the 2PbCO3·Pb(OH)2, PbSO4, and PbS exposure groups of 68-88%, 44-62%, and 6-49%, respectively. This suggests that chemical remediation using phosphate sources may be effective for immobilizing various Pb species in soils.
• Pollution and partitioning of neonicotinoid insecticides in free-grazing ducks and their eggs: Implications for human health.
  Collins Nimako; Kraisiri Khidkhan; Sittinee Kulprasertsri; Saranya Poapolathep; Paphatsara Khunlert; Yared B Yohannes; Yoshinori Ikenaka; Shouta M M Nakayama; Mayumi Ishizuka; Amnart Poapolathep
  Environmental pollution (Barking, Essex : 1987), 373, 126099, 126099, 20 Mar. 2025, [International Magazine]
  English, Scientific journal, Neonicotinoid insecticides are used extensively in many pest control schemes across the globe; but little is known about their impacts on free-grazing domestic birds and the quality of meat or eggs produced from such birds. This study assessed the pollution and partitioning of neonicotinoids in serum and eggs of free-grazing ducks from 5 provinces of Thailand and elucidated the associated human health implications. Biological samples (duck serum, egg albumins, and egg yolks) and environmental samples (soil, water, feed) were collected from 9 duck farms in Thailand and subjected to LC/MS/MS analysis. Out of 6 neonicotinoid compounds targeted, five were detected in duck serum. Imidacloprid had the greatest median concentration of 1.4 ng/mL and the highest detection frequency (df) of 85.8 % in the ducks' serum, followed by acetamiprid (median concentration = 0.4 ng/mL; df = 2.8 %), clothianidin (median concentration = 0.2 ng/mL; df = 9.4 %) or thiamethoxam (median concentration = 0.2 ng/mL; df = 7.5 %) and dinotefuran (only one sample was contaminated with 6.3 ng/mL of dinotefuran). The neonicotinoids were similarly detected in soil, water, and feed samples obtained from the duck farms, suggesting that the ducks were exposed to the insecticides from the nearby agricultural fields. The neonicotinoid compounds selectively accumulated in the albumin of duck eggs compared to yolk. The median concentration ratios of albumin to yolk obtained for imidacloprid, dinotefuran, thiamethoxam, clothianidin, and acetamiprid were 694, 463, 458, 382, and 263, respectively. However, upon human health risk analysis, levels of neonicotinoids detected in duck eggs were not found to present any appreciable risks to duck egg consumers.
• DNA damage triggers the death of green sea turtle-derived cells at high temperature.
  Masafumi Katayama; Satomi Kondo; Manabu Onuma; Shouta M M Nakayama; Tomokazu Fukuda
  Comparative biochemistry and physiology. Toxicology & pharmacology : CBP, 289, 110127, 110127, Mar. 2025, [International Magazine]
  English, Scientific journal, As temperatures rise due to increasingly severe global warming, the effect of high temperatures on wildlife, including green sea turtles, is one of the issues that must be addressed to ensure the conservation of biodiversity. In the current study, we found that green sea turtle cell death due to apoptosis occurred at 37 °C, which suppressed cell proliferation. We also found that high temperature-induced heat stress led to the accumulation of DNA damage in green sea turtle cells. DNA damage is a key factor for the induction of apoptosis. Therefore, heat stress-mediated DNA damage can trigger green sea turtle cell apoptosis. Based on these results, we predict that high temperatures, such as 37 °C, would adversely impact green sea turtles, resulting in death or health-related challenges. Importantly, this information can facilitate the conservation of green sea turtles because cellular and molecular studies regarding the effects of global warming effects remain limited.
• Sex dependent intergenerational effects of lead in mouse model.
  Nelly Banda; Nyein Chan Soe; John Yabe; Rio Doya; Yared Beyene Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta M M Nakayama
  Scientific reports, 14, 1, 30233, 30233, 04 Dec. 2024, [International Magazine]
  English, Scientific journal, Lead (Pb) exposure negatively impacts fertility in both males and females, pregnancy outcomes, and child brain development. We investigated the reproductive and neurological effects of Pb exposure on male and female mice via Pb-contaminated soil for 4 weeks. Breeding was conducted after completion of exposure, in four groups; group 1 consisted of exposed dams and unexposed sires, group 2 consisted of exposed sires and unexposed dams, group 3 consisted of exposed sires and exposed dams and group 4 was the control. Generally, Pb exposure reduced observed conception rates, with a cumulative decrement observed when both males and females are exposed. Gene expression of the testes revealed oxidative stress as the cause of reduced conception rates. Neurological tests: Morris water maze and rotarod were conducted on F1 generation offspring. Maternally and paternally exposed F1 mice performed poorly in the Morris water maze when compared to the control. The severity of the neurological effects was also parent-dependent and sex-dependent. Paternal Pb exposure effects were more pronounced in female offspring. A comparison of gene expression changes of the hippocampus and prefrontal cortex showed paternal Pb-exposure resulted in more prefrontal cortex changes than in the hippocampus, a trend also recorded in the exposed sires. The pronounced effects in female offspring of paternal Pb exposure may suggest that Pb neurological effects may be X-chromosome-linked.
• Habu vipers (Protobothrops flavoviridis) are an overlooked but important reservoir of the zoonotic tick Amblyomma testudinarium (Acari: Ixodidae) in subtropical Asia.
  Mackenzie L Kwak; Shintaro Nakagawa; So Shinya; Paula Andrea Jiménez; Greg Markowsky; Daniel McInnes; Yurie Taya; Shouta M M Nakayama; Mayumi Ishizuka; Nariaki Nonaka; Ryo Nakao
  Acta tropica, 260, 107472, 107472, 17 Nov. 2024, [International Magazine]
  English, Scientific journal, Subtropical Asia has a rich diversity of reptiles and ticks, though the role of reptiles in the sylvatic cycles of medically important ticks in the region is poorly known. Habu vipers (Protobothrops flavoviridis) are widespread and common in the Japanese subtropics but their role as hosts for ticks has not been carefully explored. For 15 months in 2023/24, habu vipers were screened for ticks and were found to be important hosts for immature stages of the tick Amblyomma testudinarium, with a 22 % infestation rate. Amblyomma testudinarium was found to have weak attachment site preferences on P. flavoviridis and host body length was found to have no relationship with either the risk of infestation or the tick load in infested snakes. The phenological profile of A. testudinarium was mapped for the first time in the subtropics based on mean tick loads on P. flavoviridis and historical flagging data. March-April were identified as the period of highest activity, May to July was a period of declining activity, August-September was a period of almost complete inactivity, and October to February was a periods of increasing activity. The role of habu vipers in the sylvatic cycle of A. testudinarium in subtropical Asia is discussion. Additionally, the potential of habu vipers to serve as reservoirs of pathogens or as dilution hosts is also explored.
• Investigating drug residues in Mongolian milk using a newly developed method with high performance liquid chromatography and a photo diode array.
  Delgermurun Dugar; Kodai Motohira; Nyamsuren Purevdorj; Bolormaa Pelden; Shouta Mm Nakayama; Mayumi Ishizuka; Yoshinori Ikenaka
  The Journal of veterinary medical science, 87, 1, 103, 109, 14 Oct. 2024, [Domestic magazines]
  English, Scientific journal, Despite the beneficial impacts of using drugs in animal husbandry, the risks of drug residues in animal products are a concern worldwide. Therefore, most countries have developed systems and methods to detect and monitor drug residues in animal products using high performance liquid chromatography (HPLC) with mass spectrometry (MS). However, MS detectors are not available in all universities; thus, we developed a new method suitable for ultraviolet detection. We first validated a new method targeting tetracycline and albendazole in milk and evaluated these drug residues in 50 samples collected from farms and supermarkets in Mongolia. The practical limit of quantification (PQL) calculated in our newly developed method was suitable to detect the maximum residual limits defined in Codex Alimentarius, and the accuracy and precision of a new method were comparable to previous studies. In particular, inter-day analysis showed great precision, with albendazole showing a 99% recovery rate with ± 3.3 of relative standard deviation (RSD). In addition, we evaluated our drugs contamination, but targeted drugs residues were not detected in the current sample set. However, this may reflect the decreased use of tetracycline in the veterinary field and seasonal use of albendazole in Mongolia. Therefore, these drugs must be continuously monitored. To the best of our knowledge, this is the first report about drug residues in milk published in an international journal by a Mongolian domestic institution. Further investigations of drug residue in Mongolia are urgently needed.
• Characterization of Neonicotinoid Metabolites by Cytochrome P450-Mediated Metabolism in Poultry.
  Adisorn Dam-On; Collins Nimako; Sittinee Kulprasertsri; Yoshinori Ikenaka; Yared B Yohannes; Shouta M M Nakayama; Mayumi Ishizuka; Saranya Poapolathep; Amnart Poapolathep; Kraisiri Khidkhan
  Toxics, 12, 8, 21 Aug. 2024, [International Magazine]
  English, Scientific journal, Neonicotinoids, a neuro-effective class of insecticides, are heavily applied in agricultural activities worldwide. Poultry can be exposed to neonicotinoids by several routes, but the knowledge of neonicotinoid's metabolism in poultry and its associated interspecies differences is highly limited. Hence, this study aims to investigate the species differences in metabolite formations, as well as cytochrome P450 (CYP)-dependent metabolism of four major neonicotinoid compounds, acetamiprid, imidacloprid, clothianidin, and thiamethoxam, in poultry. In vitro biotransformation assays using hepatic microsomes of chicken, ducks, geese, quails, and rats were conducted. Metabolites of neonicotinoids were then screened by LC/Q-TOF and quantified by LC/MS/MS. The results revealed an existence of interspecies differences in the formations of N-, low PbAc-ZnAc [12 mg/kg PbAc (3 mg PbAc/rat/day) + 0.2 mg ZnAc/rat/48 hr], high PbAc [120 mg/kg (30 mg PbAc/rat/day)], and high PbAc-ZnAc [120 mg/kg (30 mg PbAc/rat/day) + 1 mg ZnAc/rat/48 hr] for 8 weeks. A significant reduction in body weight gain was observed in the high PbAc group relative to the control group. Muscles and testes both had reduced and increased Pb uptake in low PbAc-ZnAc and high PbAc-ZnAc groups compared to PbAc only groups, respectively. Bone Pb levels in the high PbAc-ZnAc group were lower than the high PbAc group. Zinc co-administration attenuated Pb-induced inhibition of delta aminolaevulinic acid dehydratase enzyme and enhanced catalase enzyme activity at a high level of exposure. Moreover, ZnAc seems to have minimized the effects of Pb-induced mRNA dysregulation in antioxidant and antiapoptotic enzymes encoding genes. Heme oxygenase-1 was downregulated in the kidney and brain in the low PbAc group. Liver glutathione peroxidase and thioredoxin reductase-1 were downregulated in the high PbAc group. These findings suggest that zinc co-administration with lead may partially mitigate against Pb-induced toxicities.
• Simultaneous steroids measurement in dogs with hyperadrenocorticism using a column-switching liquid chromatography-tandem mass spectrometry method.
  Noboru Sasaki; Thandar Oo; Yoshikazu Yasuda; Takahiro Ichise; Noriyuki Nagata; Nozomu Yokoyama; Kazuyoshi Sasaoka; Keitaro Morishita; Shouta Mm Nakayama; Mayumi Ishizuka; Kensuke Nakamura; Mitsuyoshi Takiguchi; Yoshinori Ikenaka
  The Journal of veterinary medical science, 83, 11, 1634, 1642, 31 Oct. 2021, [Domestic magazines]
  English, Scientific journal, We developed an analytical method using an on-line column-switching liquid chromatography with triple quadrupole mass spectrometry (LC/MS/MS) for quantifying multiple steroids in serum. Using the developed method, we evaluated the serum concentration of nine steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 21-deoxycortisol, deoxycorticosterone, progesterone, 17α-OH-progesterone and aldosterone) in dogs with hyperadrenocorticism (HAC). Serum was mixed with stable isotope internal standards and thereafter purified by the automated column-switching system. The limit of detection ranged 2-16 pg/ml for nine steroids. In the baseline samples, five steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, and 17α-OH-progesterone) were detected in all dogs. The concentrations of cortisone, 11-deoxycortisol, and 17α-OH-progesterone in dogs with HAC (n=19) were significantly higher those in dogs without HAC (n=15, P<0.02). After the adrenocorticotropic hormone stimulation test, six steroids (cortisol, corticosterone, cortisone, 11-deoxycortisol, 17α-OH-progesterone, and deoxycorticosterone) were above the limit of quantification in all dogs. Cortisol, corticosterone, cortisone, and deoxycorticosterone concentrations of dogs with HAC were significantly higher than those of dogs without HAC (P<0.02). In addition, 11-deoxycortisol and 17α-OH-progesterone concentration was higher in dogs with HAC than in dogs without HAC (P=0.044 and P=0.048, respectively). The on-line column-switching LC/MS/MS would be feasible for measuring multiple steroids in dog serum. The results suggest that cortisone, 11-deoxycortisol, and 17α-OH-progesterone would be related to HAC. Further studies are warranted to assess the clinical feasibility of steroid profile in dogs with HAC.
• Solid-Phase Partitioning and Leaching Behavior of Pb and Zn from Playground Soils in Kabwe, Zambia.
  Walubita Mufalo; Pawit Tangviroon; Toshifumi Igarashi; Mayumi Ito; Tsutomu Sato; Meki Chirwa; Imasiku Nyambe; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  Toxics, 9, 10, 04 Oct. 2021, [International Magazine]
  English, Scientific journal, Zambia's Kabwe mine wastes (KMWs) are responsible for contaminating the surrounding soil and dust in the Kabwe district. Unfortunately, these wastes arise from the historical mining activities of lead (Pb) and Zinc (Zn), which lacked adequate waste management strategies. As a result, potentially toxic elements (PTEs) (Pb and Zn) spread across the Kabwe district. To assess the soil pollution derived from previous mining activities, we studied topsoil samples (n = 8) from the school playground soils (SPs). In this study, the degree of contamination, geochemical partitioning, and leachability, coupled with the release and retention of Pb and Zn, were studied. The SPs were classified as extremely enriched (EF > 40) and contaminated with Pb (Igeo > 5). On average, Pb (up to 89%) and Zn (up to 69%) were bound with exchangeable, weak acid-soluble, reducible and oxidizable phases, which are considered as 'geochemically mobile' phases in the environment. The leachates from the soils (n = 5) exceeded the Zambian standard (ZS: 190:2010) for Pb in potable drinking water (Pb < 0.01 mg/L). Furthermore, the spatial distribution of Pb and Zn showed a significant reduction in contents of Pb and Zn with the distance from the mine area.
• Lead concentrations and isotope ratios in blood, breastmilk and feces: contribution of both lactation and soil/dust exposure to infants in a lead mining area, Kabwe, Zambia.
  Haruya Toyomaki; John Yabe; Shouta M M Nakayama; Yared B Yohannes; Kaampwe Muzandu; Tiza Mufune; Hokuto Nakata; Yoshinori Ikenaka; Takeshi Kuritani; Mitsuhiro Nakagawa; Kennedy Choongo; Mayumi Ishizuka
  Environmental pollution (Barking, Essex : 1987), 286, 117456, 117456, 01 Oct. 2021, [International Magazine]
  English, Scientific journal, Lead (Pb) poses a serious public health concern. Breastmilk may be a possible source of Pb exposure in infants, as Pb can be transferred from the maternal blood to breastmilk. The present study was undertaken to determine the Pb exposure and the contribution of lactation as one of the exposure pathways to infants in a Pb mining area, Kabwe, Zambia. Blood, breastmilk and infants' feces were collected from 418 pairs of infants and mothers. The Pb concentrations, isotope ratios in the samples, and biochemistry in mothers' plasma were analyzed. The overall mean of blood lead levels (BLLs) in infants and mothers were 18.0 and 11.3 μg/dL, respectively. High Pb concentration in breastmilk (range: 0.4-51.9, mean: 5.3 μg/L) above the WHO acceptable level between 2 and 5 μg/L were found and could be one of the sources of Pb exposure in infants. The Pb isotope ratios in infants' feces were the most similar to Pb ratios in the soil samples. The results suggest that infants are also exposed to Pb from the environment. Pb exposure in infants through breastfeeding and soil ingestion could potentially exceed daily intake of Pb which causes neurodevelopmental toxicity. In contrast to the high BLLs in mothers, the plasma biochemical profiles of most analyzed parameters were interestingly within, or close to, the standard reference values. Our data suggest that environmental remediation is urgently needed to reduce the Pb exposure in infants and mothers from the environment in Kabwe in parallel with chelation therapy.
• Cushing症候群と肝細胞癌を合併した犬におけるステロイド値の包括的解析(Comprehensive analysis of steroid profile in dogs with Cushing' syndrome and hepatocellular carcinoma)
  Oo Thandar; 佐々木 東; 池中 良徳; 永田 矩之; 一瀬 貴大; Bin Teoh Yong; 川元 誠; 小島 一輝; 菅原 芽伊; 中山 翔太; 石塚 真由美; 中村 健介; 滝口 満喜
  日本獣医学会学術集会講演要旨集, 164回, [HSO, 18], (公社)日本獣医学会, Sep. 2021
  English
• Geolocators link marine mercury with levels in wild seabirds throughout their annual cycle: Consequences for trans-ecosystem biotransport.
  Akiko Shoji; Kyle H Elliott; Yutaka Watanuki; Niladri Basu; Shannon Whelan; Joshua Cunningham; Scott Hatch; Hazuki Mizukawa; Shouta M M Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Stéphane Aris-Brosou
  Environmental pollution (Barking, Essex : 1987), 284, 117035, 117035, 01 Sep. 2021, [International Magazine]
  English, Scientific journal, Seabirds are widely used as indicators of marine pollution, including mercury (Hg), because they track contaminant levels across space and time. However, many seabirds are migratory, and it is difficult to understand the timing and location of their Hg accumulation. Seabirds may obtain Hg thousands of kilometers away, during their non-breeding period, and deposit that Hg into their terrestrial breeding colonies. We predicted that Hg concentration in rectrices reflects exposure during the previous breeding season, in body feathers reflects non-breeding exposure, and in blood collected during breeding reflects exposure during current breeding. To test this hypothesis, we measured total Hg concentration in these three tissues, which reflect different timepoints during the annual cycle of rhinoceros auklets (Cerorhinca monocerata) breeding on both sides of the North Pacific (Middleton Island in Alaska and Teuri Island in Hokkaido), and tracked their wintering movement patterns with biologging devices. We (i) identify the wintering patterns of both populations, (ii) examine Hg levels in different tissues representing exposure at different time periods, (iii) test how environmental Hg exposure during the non-breeding season affects bird contamination, and (iv) assess whether variation in Hg levels during the non-breeding season influences levels accumulated in terrestrial plants. Individuals from both populations followed a figure-eight looping migration pattern. We confirm the existence of a pathway from environmental Hg to plant roots via avian tissues, as Hg concentrations were higher in plants within the auklet colonies than at control sites. Hg concentrations of breast feathers were higher in Alaskan than in Japanese auklets, but Hg concentrations in rectrices and blood were similar. Moreover, we found evidence that tissues with different turnover rates could record local anthropogenic Hg emission rates of areas visited during winter. In conclusion, Hg was transported across thousands of kilometers by seabirds and transferred to local plants.
• Simultaneous quantification of imidacloprid and its metabolites in tissues of mice upon chronic low-dose administration of imidacloprid.
  Collins Nimako; Yoshinori Ikenaka; Osei Akoto; Kazutoshi Fujioka; Kumiko Taira; Koji Arizono; Keisuke Kato; Keisuke Takahashi; Shouta M M Nakayama; Takahiro Ichise; Mayumi Ishizuka
  Journal of chromatography. A, 1652, 462350, 462350, 30 Aug. 2021, [International Magazine]
  English, Scientific journal, This study aimed to (i) develop a sensitive method for simultaneous detection and quantification of imidacloprid (IMI) and seven of its metabolites in tissue specimens, and to (ii) determine the biodistribution of the IMI compounds in tissues of C57BL/6J male mice; after exposure to 0.6 mg/kg bw/day of IMI (10% of no observable adverse effect level of IMI) through a powdered diet for 24 weeks. We successfully developed a method which was accurate (recoveries were ≥ 70% for most compounds), sensitive (LODs ≤ 0.47 ng/mL and LOQs ≤ 1.43 ng/mL were recorded for all detected compounds, R2 ≥ 0.99) and precise (RSDs ≤ 20%) for routine analysis of IMI and seven of its metabolites in blood and various tissue matrices. After bio-distributional analysis, IMI and five of its metabolites were detected in mice. Brain, testis, lung, kidney, inguinal white adipose tissue and gonadal white adipose tissue mainly accumulated IMI, blood and mesenteric white adipose tissue mainly accumulated IMI-olefin; liver mainly accumulated desnitro-IMI; pancreas predominately accumulated 4-hydroxy-IMI. The desnitro-dehydro-IMI and the desnitro-IMI metabolites recorded tissue-blood concentration ratios ≥ 1.0 for testis, brain, lung and kidney. The cumulative levels of the six detected IMI compounds (Σ6 IMI compounds) were found in the decreasing order: blood > testis > brain > kidney > lung > iWAT > gWAT > mWAT > liver > pancreas. Altogether, this study provided essential data needed for effective mechanistic elucidation of compound-specific adverse outcomes associated with chronic exposures to IMI in mammalian species.
• Evaluation of Dispersion of Lead-Bearing Mine Wastes in Kabwe District, Zambia
  Shinsaku Nakamura; Toshifumi Igarashi; Yoshitaka Uchida; Mayumi Ito; Kazuyo Hirose; Tsutomu Sato; Walubita Mufalo; Meki Chirwa; Imasiku Nyambe; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  MINERALS, 11, 8, Aug. 2021
  English, Scientific journal
• Human Exposures to Neonicotinoids in Kumasi, Ghana.
  Collins Nimako; Yoshinori Ikenaka; Osei Akoto; Nesta Bortey-Sam; Takahiro Ichise; Shouta M M Nakayama; Kwadwo A Asante; Kazutoshi Fujioka; Kumiko Taira; Mayumi Ishizuka
  Environmental toxicology and chemistry, 40, 8, 2306, 2318, Aug. 2021, [International Magazine]
  English, Scientific journal, Neonicotinoid insecticides (NNIs) are now popular in many agricultural systems across Africa; however, the extent of human exposures to NNIs in African countries is scarcely reported. The present study evaluates neonicotinoid exposures in the consumer population of Kumasi, a cosmopolitan city in Ghana. A total of 75 human urine samples were collected from healthy volunteers (nonfarmers, aged 13-80 yr) and analyzed with a liquid chromatography electrospray ionization tandem mass spectrometry system. Seven NNIs and 3 NNI metabolites were detected in the following pattern (frequency, median concentration, maximum concentration): N-dm-acetamiprid (94.7%, 0.41 µg/L, 8.79 µg/L) > imidacloprid (70.7%, 0.15 µg/L, 211.62 µg/L) > N-(6-chloro-3-pyridylmethyl)-N-ethyl-N'-methylformamidine (62.2%, 0.43 µg/L, 53.85 µg/L) > 2-[N-(6-chloro-3-pyridylmethyl)-N-ethylamino]-2-(methylimino)acetic acid (56.8%, 0.10 µg/L, 3.53 µg/L) > clothianidin (40%, >limit of quantification [LOQ], 0.45 µg/L) > nitenpyram (18.7%, >LOQ, 0.14 µg/L) ≈ thiamethoxam (18.7%, >LOQ, 0.21 µg/L) > dinotefuran (12.0%, >LOQ, 1.01 µg/L) > acetamiprid (2.7%, >LOQ, 0.08 µg/L) ≈ thiacloprid (2.7%, >LOQ, 0.14 µg/L). Approximately 92% of the subjects were found to be exposed to multiple neonicotinoids simultaneously. The mean, median, and maximum imidacloprid equivalent of the relative potency factor of NNIs were found to be 1.6, 0.5, and 22.52, respectively. The median estimated daily intakes of acetamiprid, imidacloprid, and nitenpyram were 0.47, 1.27, and 0.02 µg/kg/d for females and 0.91, 0.66, and 0.08 µg/kg/d for males, respectively. The maximum daily intakes of all the NNIs were <1% of their chronic reference doses (cRfDs), except for imidacloprid and thiacloprid which recorded maximum daily intakes corresponding to 17.97 and 8.28% of cRfDs, respectively. To the best of our knowledge, the present study is the first biomonitoring report on neonicotinoid insecticides in Africa. Environ Toxicol Chem 2021;40:2306-2318. © 2021 SETAC.
• 二光子顕微鏡を用いた、ニコチン性アセチルコリン受容体アゴニストによる脳機能障害の検出
  平井 杏梨; 杉尾 翔太; Nimako Collins; 中山 翔太; 加藤 恵介; 高橋 圭介; 有薗 幸司; 平野 哲史; 星 信彦; 藤岡 一俊; 平 久美子; 石塚 真由美; 和氣 弘明; 池中 良徳
  The Journal of Toxicological Sciences, 46, Suppl., S102, S103, (一社)日本毒性学会, Jul. 2021
  English
• The effects of fipronil on emotional and cognitive behaviors in mammals.
  Tomohiro Suzuki; Anri Hirai; Kraisiri Khidkhan; Collins Nimako; Takahiro Ichise; Kazuki Takeda; Hazuki Mizukawa; Shouta M M Nakayama; Kei Nomiyama; Nobuhiko Hoshi; Mizuki Maeda; Tetsushi Hirano; Kazuyoshi Sasaoka; Noboru Sasaki; Mitsuyoshi Takiguchi; Mayumi Ishizuka; Yoshinori Ikenaka
  Pesticide biochemistry and physiology, 175, 104847, 104847, Jun. 2021, [International Magazine]
  English, Scientific journal, Fipronil is a phenylpyrazole insecticide that is widely used as a pesticide and a veterinary drug, although studies suggest that it could be toxic to mammals. The objectives of this study were to examine the pharmacokinetic profile of fipronil in mice, dogs, and cats, and to evaluate its effects on emotional and cognitive behaviors of dogs and cats using the data obtained from mice. The assessment of in vivo kinetics of fipronil was conducted in mice and dogs. We also performed behavioral tests (elevated plus-maze and Y-maze) and measured the levels of neurotransmitters in mice exposed to fipronil. In addition, the in vitro metabolism of fipronil were evaluated using liver microsomes of rats, mice, dogs, and cats. The results revealed that fipronil is distributed throughout the body (blood, brain, adipose tissue, and liver) of mice after dermal application. It was metabolized to fipronil sulfone primarily in the liver. The data on kinetics show that both fipronil and fipronil sulfone have a longer half-life in dogs and cats than in mice. The behavioral tests indicated that fipronil and fipronil sulfone could affect emotional and cognitive behaviors and alter the levels of neurotransmitters (dopamine in the striatum and serotonin in the hippocampus) in mice. Furthermore, we found that dogs and cats have a low ability to metabolize fipronil than mice and rats. However, further comprehensive studies are needed to determine whether fipronil affects the emotional and cognitive behaviors when administered to dogs and cats. To the best of our knowledge, this is the first study to examine the pharmacokinetic data and verify the effects of fipronil on emotional and cognitive behaviors of dogs and cats using the data obtained from mice.
• Genome-wide DNA methylation analysis of dogs with high lead exposure living near a lead mining area in Kabwe, Zambia.
  Jumpei Yamazaki; Haruya Toyomaki; Shouta M M Nakayama; John Yabe; Kaampwe Muzandu; Jaroslav Jelinek; Shoko Yokoyama; Yoshinori Ikenaka; Mitsuyoshi Takiguchi; Mayumi Ishizuka
  Environmental pollution (Barking, Essex : 1987), 286, 117229, 117229, 03 May 2021, [International Magazine]
  English, Scientific journal, Lead (Pb) is a heavy metal that has been proven to be toxic to both animals and humans. Genom-wide DNA methylation in domestic dogs exposed to high levels of Pb in Kabwe, Zambia was analyzed in this study. Using next-generation sequencing on samples from 20 domestic dogs (mean blood Pb concentration: 43.6 μg/dL and 7.2 μg/dL in the high and low exposure groups), a digital restriction enzyme analysis of methylation was performed to identify the genomic locations of differentially methylated CpG sites. A validation study on an additional 20 dogs followed (blood Pb concentration: 4.9-29.7 μg/dL). The cluster analysis resolved two broad clusters indicating high and low Pb exposure. The study identified 827 (1.2%) CpG sites with differences in methylation (101 CpG sites were hypermethylated in the low exposure group and 726 were hypermethylated in the high exposure group). The sites corresponded to 26 genes with differentially methylated CpG sites at their promoter regions, including the NGF gene. The methylation of four CpG sites was validated using bisulfite pyrosequencing. The results indicate that aberrant hypermethylation is prevalent in dogs exposed to Pb. The altered DNA methylation of the genes identified in this study contributes to a greater understanding of the epigenetic changes caused by Pb exposure and highlights novel biomarker discoveries across species.
• Delta-aminolevulinic acid dehydratase (ALAD) and vitamin D receptor (VDR) genes polymorphisms in children residing in an abandoned lead-zinc mine area in Kabwe, Zambia
  Yared B. Yohannes; Shouta M. M. Nakayama; John Yabe; Haruya Toyomaki; Andrew Kataba; Hokuto Nakata; Kaampwe Muzandu; Yoshinori Ikenaka; Kennedy Choongo; Mayumi Ishizuka
  META GENE, 27, Feb. 2021
  English, Scientific journal
• An Investigation of the Wild Rat Crown Incisor as an Indicator of Lead (Pb) Exposure Using Inductively Couple Plasma Mass Spectrometry (ICP-MS) and Laser Ablation ICP-MS.
  Andrew Kataba; Shouta M M Nakayama; Hokuto Nakata; Haruya Toyomaki; Yared B Yohannes; John Yabe; Kaampwe Muzandu; Golden Zyambo; Ayano Kubota; Takehisa Matsukawa; Kazuhito Yokoyama; Yoshinori Ikenaka; Mayumi Ishizuka
  International journal of environmental research and public health, 18, 2, 18 Jan. 2021, [International Magazine]
  English, Scientific journal, Lead (Pb) is a metal toxicant of great public health concern. The present study investigated the applicability of the rat incisor in Pb exposure screening. The levels of lead in teeth (Pb-T) in the crown and root of incisors in laboratory Pb-exposed Sprague Dawley rats were quantified using inductively coupled plasma mass spectrometry (ICP-MS). The crown accumulated much Pb-T than the root of the Sprague Dawley rat incisor. The levels of lead in blood (Pb-B) were positively correlated with the Pb-T in the crown and root incisors of the Sprague Dawley rats. As an application of the Pb-T crown results in experimental rats, we subsequently analyzed the Pb-T in the crown incisors of Pb-exposed wild rats (Rattus rattus) sampled from residential sites within varying distances from an abandoned lead-zinc mine. The Pb-T accumulation in the crown of incisors of R. rattus rats decreased with increased distance away from the Pb-Zn mine. Furthermore, the Pb-T was strongly correlated (r = 0.85) with the Pb levels in the blood. Laser ablation ICP-MS Pb-T mappings revealed a homogenous distribution of Pb in the incisor with an increased intensity of Pb-T localized in the tip of the incisor crown bearing an enamel surface in both Sprague Dawley and R. rattus rats. These findings suggest that Pb-T in the crown incisor may be reflective of the rat's environmental habitat, thus a possible indicator of Pb exposure.
• Chronic low-dose exposure to imidacloprid potentiates high fat diet-mediated liver steatosis in C57BL/6J male mice
  NIMAKO Collins; IKENAKA Yoshinori; OKAMATSU-OGURA Yuko; BARIUAN Jussiaea V.; KOBAYASHI Atsushi; YAMAZAKI Ryo; TAIRA Kumiko; HOSHI Nobuhiko; HIRANO Tetsushi; NAKAYAMA Shouta M. M.; ISHIZUKA Mayumi
  Journal of Veterinary Medical Science, 83, 3, 487, 500, JAPANESE SOCIETY OF VETERINARY SCIENCE, 2021
  English, Hepatic steatosis is known to precede a continuum of events that lead to hepatic metabolic dysfunction, inflammation and carcinogenesis. Recently, studies have linked xenobiotic exposures to hepatic steatogenesis and its associated metabolic disorders; however, the underlying mechanisms remain elusive. This study aimed to elucidate the mechanistic role of imidacloprid in the prevalence of high fat diet (HFD)-induced liver steatosis, using a C57BL/6J mice model. Mice (3 weeks old) were fed with HFD and treated with 0.6 mg/kg bw/day (one-tenth of the NOAEL) of imidacloprid through water or diet, for 24 weeks. In a controlled group, mice were fed with only HFD. At the end of the study, imidacloprid treatment significantly potentiated HFD-induced body weight gain in mice. Also, imidacloprid increased the liver weights of mice, with complimentary reductions in mesenteric and gonadal white adipose tissue weights. Histopathological analysis of liver revealed a drastic steatosis in imidacloprid treated mice. Following a real-time qPCR analysis, imidacloprid upregulated transcriptions of hepatic fatty acid biosynthesis-related transcription factors and genes. Imidacloprid also induced hepatic expression of the gene encoding pregnane X receptor; but had no significant effect on hepatic expressions of liver X receptor and aryl hydrocarbon receptor. The imidacloprid treatment further enhanced serum alanine aminotransferase levels but downregulated hepatic antioxidant mRNA expressions. Ultimately, this study suggested an imidacloprid-potentiation effects on prevalence of HFD-induced liver steatosis via transcriptional modulations of the hepatic FA biosynthesis pathway.
• Simultaneous Detection Technique and Chronic Low-dose Accumulation Trends of Imidacloprid and its Metabolites in Tissues of C57BL/6J Mice
  NIMAKO Collins; IKENAKA Yoshinori; AKOTO Osei; FUJIOKA Kazutoshi; TAIRA Kumiko; ARIZONO Koji; KATO Keisuke; TAKAHASHI Keisuke; NAKAYAMA Shouta M.M.; ICHISE Takahiro; ISHIZUKA Mayumi
  Annual Meeting of the Japanese Society of Toxicology, 48.1, P-154E, The Japanese Society of Toxicology, 2021
  Japanese, The present study aimed to (i) develop a sensitive LC-MS/MS-based technique for simultaneous detection and quantification of Imidacloprid (IMI) and its metabolites in tissue specimens, and to (ii) determine the specific bioaccumulation trends of the IMI compounds in organs of C57BL/6J male mice; after exposure to 0.6 mg/kg bw/day of IMI (10% of NOAEL) through a powdered diet for 24 weeks. We successfully developed a method which was accurate (recoveries were ≥ 70% for most compounds), sensitive (LODs ≤ 0.47 ng/mL, LOQs ≤ 1.43 ng/mL and R2 ≥ 0.99) and precise (RSDs ≤ 20%) for routine analysis of IMI and seven of its metabolites in in blood and various tissues of mice. Upon biodistribution analysis, IMI and five of its metabolites were detected in various organs within mice. Blood, liver, mesenteric white adipose tissue and pancreas mainly accumulated IMI-olefin; brain, testis, inguinal white adipose tissue and gonadal white adipose tissue mainly accumulated IMI, whereas the kidney mainly accumulated 4-hydroxy-IMI. The N-desnitro-IMI metabolite showed unique accumulation in brain and testis by recording brain-blood and testis-blood detection ratios of 8.4 and 7.6, respectively. Cumulative levels of the six detected IMI compounds (Σ6 IMI compounds) were found in the decreasing order; blood > testis > iWAT > kidney > brain > gWAT > mWAT > pancreas > liver. The current study provides essential data needed for effective mechanistic elucidation of compound-specific adverse outcomes associated with chronic exposures to IMI in mammalian species.
• Introduction: Cooperation with Mongolian University of Life Sciences in research activity
  Motohira Kodai; Dugar Delgermurun; Ikenaka Yoshinori; Nakayama Shouta; Pelden Bolormaa; Gendenpil Lkhamjav; Ishizuka Mayumi
  Proceedings of the Annual Meeting of Japan Society for Science Education, 45, 563, 564, Japan Society for Science Education, 2021
  Japanese, 発表者は北海道大学のJICAを通じたプロジェクトの一環で２０１９年に青年海外協力隊（獣医師）としてモンゴル生命科学大学獣医学部に短期派遣され、約１か月の研究支援を実施した。モンゴル国では残留抗生物質の検査体制の拡大が望まれており、発表者の活動により、日本から大学研究レベルの検査手法の開発とその研究プロセスの伝達、共有が実現された。帰国後も、現在に至るまでFacebook Messengerなどのツールを利用し、追加の検査手法開発に向けた継続的な研究協力関係を構築した。結果として、国際会議における科学的成果発表など、今回の活動により一定の進展があったことを社会に報告できた。しかし、専門性の高い研究レベルの支援を遠隔で実施する過程で双方、難点を抱える場面があった。本発表により発表者が実施した研究支援を踏まえ、開発途上国に対する大学研究レベルの支援の一例紹介、またその課題を共有する。
• Neonicotinoid residues in commercial Japanese tea leaves produced by organic and conventional farming methods.
  Collins Nimako; Anri Hirai; Takahiro Ichise; Osei Akoto; Shouta M M Nakayama; Kumiko Taira; Kazutoshi Fujioka; Mayumi Ishizuka; Yoshinori Ikenaka
  Toxicology reports, 8, 1657, 1664, 2021, [International Magazine]
  English, Scientific journal, The current study sought to assess the residual levels of neonicotinoid insecticides (NEO) in organic and conventional green tea leaves produced in Japan. A total of 103 tea leaves (thus, 42 organic and 61 conventional), were sampled from grocery stores in Japan. Concentrations of NEOs in the tea leaves were quantified using LC-MS/MS; and the data was used to estimate maximum daily intakes of NEOs within the Japanese population. Seven native NEO compounds and one NEO metabolite were detected in both organic and conventional tea leaves. Detection frequencies (%Dfs) of NEOs in the tea samples (n = 103) were found in the decreasing order; thiacloprid (84.47 %) > dinotefuran (74.76 %) > imidacloprid (69.90 %) ≈ clothianidin (69.90 %) > dm-acetamiprid (63.11 %) > thiamethoxam (58.25 %) > acetamiprid (4.85 %) > nitenpyram (1.94 %). About 94.20 % of the tea leaves contained two or more NEO compounds simultaneously. The %Dfs of NEOs were relatively lower in organic tea leaves, compared to the conventional tea leaves. Various percentile concentrations of NEOs were far lower in organic tea leaves, compared to the conventional tea leaves. The maximum daily intakes of NEOs through consumption of tea (MDIgt) were also lower for organic tea leaves, compared to the conventional tea samples.
• Chronic low-dose exposure to imidacloprid potentiates high fat diet-mediated liver steatosis in C57BL/6J male mice
  NIMAKO Collins; IKENAKA Yoshinori; IKENAKA Yoshinori; OKAMATSU-OGURA Yuko; BARIUAN Jussiaea V.; KOBAYASHI Atsushi; YAMAZAKI Ryo; TAIRA Kumiko; HOSHI Nobuhiko; HIRANO Tetsushi; NAKAYAMA Shouta M. M.; ISHIZUKA Mayumi
  Journal of Veterinary Medical Science (Web), 83, 3, 487, 500, 2021, [Domestic magazines]
  English, Scientific journal, Hepatic steatosis is known to precede a continuum of events that lead to hepatic metabolic dysfunction, inflammation and carcinogenesis. Recently, studies have linked xenobiotic exposures to hepatic steatogenesis and its associated metabolic disorders; however, the underlying mechanisms remain elusive. This study aimed to elucidate the mechanistic role of imidacloprid in the prevalence of high fat diet (HFD)-induced liver steatosis, using a C57BL/6J mice model. Mice (3 weeks old) were fed with HFD and treated with 0.6 mg/kg bw/day (one-tenth of the NOAEL) of imidacloprid through water or diet, for 24 weeks. In a controlled group, mice were fed with only HFD. At the end of the study, imidacloprid treatment significantly potentiated HFD-induced body weight gain in mice. Also, imidacloprid increased the liver weights of mice, with complimentary reductions in mesenteric and gonadal white adipose tissue weights. Histopathological analysis of liver revealed a drastic steatosis in imidacloprid treated mice. Following a real-time qPCR analysis, imidacloprid upregulated transcriptions of hepatic fatty acid biosynthesis-related transcription factors and genes. Imidacloprid also induced hepatic expression of the gene encoding pregnane X receptor; but had no significant effect on hepatic expressions of liver X receptor and aryl hydrocarbon receptor. The imidacloprid treatment further enhanced serum alanine aminotransferase levels but downregulated hepatic antioxidant mRNA expressions. Ultimately, this study suggested an imidacloprid-potentiation effects on prevalence of HFD-induced liver steatosis via transcriptional modulations of the hepatic FA biosynthesis pathway.
• Aging-related changes in the sensitivity of behavioral effects of the neonicotinoid pesticide clothianidin in male mice
  Hirano Tetsushi; Miyata Yuka; Kubo Shizuka; Ohno Shuji; Onaru Kanoko; Maeda Mizuki; Kitauchi Sayaka; Nishi Misaki; Tabuchi Yoshiaki; Ikenaka Yoshinori; Ikenaka Yoshinori; Ichise Takahiro; Nakayama Shouta M.M.; Ishizuka Mayumi; Arizono Koji; Takahashi Keisuke; Kato Keisuke; Mantani Youhei; Yokoyama Toshifumi; Hoshi Nobuhiko
  Toxicology Letters, 342, 95, 103, 2021, [International Magazine]
  English, Scientific journal, Neonicotinoids, which act as agonists of the nicotinic acetylcholine receptors of insects, are widely used pesticides worldwide. Although epidemiological studies revealed that the detection amounts of neonicotinoids in urine are higher in the elderly population than other age-groups, there is no available information regarding the risks of neonicotinoids to older mammals. This study was aimed to investigate aging-related differences in the behavioral effects of the neonicotinoid pesticide clothianidin (CLO). We acutely administered a sub-NOAEL level (5 mg/kg) of CLO to adult (12-week-old) and aging (90-week-old) mice and conducted four behavioral tests focusing on the emotional behavior. In addition, we measured the concentrations of CLO and its metabolites in blood, brain and urine. There were age-related changes in most parameters in all behavioral tests, and CLO significantly decreased the locomotor activity in the open field test and elevated plus-maze test in the aging group, but not in the adult group. The concentrations of most CLO and its metabolites were significantly higher in the blood and brain and were slightly lower in the urine in the aging group compared to the adult group. These findings should contribute to our understanding of age-related differences in the adverse effects of neonicotinoids in mammals.
• Sensitivity of turtles to anticoagulant rodenticides: Risk assessment for green sea turtles (Chelonia mydas) in the Ogasawara Islands and comparison of warfarin sensitivity among turtle species
  Yamamura Yoshiya; Takeda Kazuki; Kawai Yusuke K.; Ikenaka Yoshinori; Ikenaka Yoshinori; Kitayama Chiyo; Kondo Satomi; Kezuka Chiho; Taniguchi Mari; Ishizuka Mayumi; Nakayama Shouta M.M.
  Aquatic Toxicology, 233, 105792, 105792, 2021, [International Magazine]
  English, Scientific journal, Although anticoagulant rodenticides (ARs) are effectively used for the control of invasive rodents, nontarget species are also frequently exposed to ARs and secondary poisonings occur widely. However, little data is available on the effects of ARs, especially on marine organisms. To evaluate the effects of ARs on marine wildlife, we chose green sea turtles (Chelonia mydas), which are one of the most common marine organisms around the Ogasawara islands, as our primary study species. The sensitivity of these turtles to ARs was assessed using both in vivo and in vitro approaches. We administered 4 mg/kg of warfarin sodium either orally or intravenously to juvenile green sea turtles. The turtles exhibited slow pharmacokinetics, and prolongation of prothrombin time (PT) was observed only with intravenous warfarin administration. We also conducted an in vitro investigation using liver microsomes from green sea turtles, and two other turtle species (softshell turtle and red-eared slider) and rats. The cytochrome P450 metabolic activity in the liver of green sea turtles was lower than in rats. Additionally, vitamin K epoxide reductase (VKOR), which is the target enzyme of ARs, was inhibited by warfarin in the turtles at lower concentration levels than in rats. These data indicate that turtles may be more sensitive to ARs than rats. We expect that these findings will be helpful for sea turtle conservation following accidental AR-broadcast incidents.
• Assessment of LeadCare II analysis for testing of a wide range of blood lead levels in comparison with ICP-MS analysis
  Nakata Hokuto; Nakayama Shouta M.M.; Yabe John; Muzandu Kaampwe; Toyomaki Haruya; Yohannes Yared Beyene; Yohannes Yared Beyene; Kataba Andrew; Kataba Andrew; Zyambo Golden; Ikenaka Yoshinori; Ikenaka Yoshinori; Choongo Kennedy; Choongo Kennedy; Ishizuka Mayumi
  Chemosphere, 271, 129832, 129832, 2021, [International Magazine]
  English, Scientific journal, The LeadCare® testing system, which utilizes anodic stripping voltammetry (ASV) methodology, has been widely used worldwide for cost-effective blood lead level (BLL) screening. However, some concerns have recently been issued regarding inaccurate results obtained using LeadCare®. Hence, we aimed to evaluate the accuracy of BLL measured by LeadCare® II (BLLLC) by comparison with ICP-MS (BLLIM) by the Passing-Bablok regression, Deming regression, and Bland-Altman analyses by using 994 venous blood samples. BLLLC ranged from 3.3 to 162.3 μg/dL, while BLLIM ranged from 0.8 to 154.8 μg/dL. Although BLLLC and BLLIM exhibited a strong and positive correlation, BLLLC values were generally greater than BLLIM values, indicative of the overestimation of the LeadCare® analysis. A large positive bias of 19.15 ± 8.26 μg/dL and 29.25 ± 14.04 μg/dL for BLLLC compared with BLLIM were recorded in the BLLLC range of 45.0-64.9 μg/dL and for ≥65.0 μg/dL, respectively. In contrast, a bias of ≤0.3 μg/dL was observed at a BLLLC of less than 10.0 μg/dL. Blood copper, cadmium, and iron levels did not exhibit an effect on the bias of BLLLC, indicative of the minimal potential interferences of the metals; these interferences are a cause for concern with the ASV method. In conclusion, LeadCare® analysis is thought to be a good tool for screening purposes at a lower BLL around the reference level of 5 μg/dL in the initial stage; however, conversion or retesting using a laboratory analyzer is recommended at a higher BLL for appropriate clinical evaluation and research.
• The VKORC1 ER-luminal loop mutation (Leu76Pro) leads to a significant resistance to warfarin in black rats (Rattus rattus)
  Takeda Kazuki; Ikenaka Yoshinori; Ikenaka Yoshinori; Fourches Denis; Tanaka Kazuyuki D.; Nakayama Shouta M.M.; Triki Dhoha; Li Xinhao; Igarashi Manabu; Igarashi Manabu; Tanikawa Tsutomu; Ishizuka Mayumi
  Pesticide Biochemistry and Physiology, 173, 104774, 104774, 2021, [International Magazine]
  English, Scientific journal, Well-known 4-hydroxycoumarin derivatives, such as warfarin, act as inhibitors of the vitamin K epoxide reductase (VKOR) and are used as anticoagulants. Mutations of the VKOR enzyme can lead to resistance to those compounds. This has been a problem in using them as medicine or rodenticide. Most of these mutations lie in the vicinity of potential warfarin-binding sites within the ER-luminal loop structure (Lys30, Phe55) and the transmembrane helix (Tyr138). However, a VKOR mutation found in Tokyo in warfarin-resistant rats does not follow that pattern (Leu76Pro), and its effect on VKOR function and structure remains unclear. We conducted both in vitro kinetic analyses and in silico docking studies to characterize the VKOR mutant. On the one hand, resistant rats (R-rats) showed a 37.5-fold increased IC50 value to warfarin when compared to susceptible rats (S-rats); on the other hand, R-rats showed a 16.5-fold lower basal VKOR activity (Vmax/Km). Docking calculations exhibited that the mutated VKOR of R-rats has a decreased affinity for warfarin. Molecular dynamics simulations further revealed that VKOR-associated warfarin was more exposed to solvents in R-rats and key interactions between Lys30, Phe55, and warfarin were less favored. This study concludes that a single mutation of VKOR at position 76 leads to a significant resistance to warfarin by modifying the types and numbers of intermolecular interactions between the two.
• Analysis of lead distribution in avian organs by LA-ICP-MS: Study of experimentally lead-exposed ducks and kites
  Torimoto Ryouta; Ishii Chihiro; Sato Hiroshi; Saito Keisuke; Watanabe Yukiko; Ogasawara Kohei; Kubota Ayano; Matsukawa Takehisa; Matsukawa Takehisa; Yokoyama Kazuhito; Yokoyama Kazuhito; Kobayashi Atsushi; Kimura Takashi; Nakayama Shouta M.M.; Ikenaka Yoshinori; Ikenaka Yoshinori; Ishizuka Mayumi
  Environmental Pollution, 283, 117086, 117086, 2021, [International Magazine]
  English, Scientific journal, Lead poisoning of wild birds by ingestion of lead ammunition occurs worldwide. Histopathological changes in organs of lead-intoxicated birds are widely known, and lead concentration of each organ is measurable using mass spectrometry. However, detailed lead localization at the suborgan level has remained elusive in lead-exposed birds. Here we investigated the detailed lead localization in organs of experimentally lead-exposed ducks and kites by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). In both the ducks and kites, lead accumulated diffusely in the liver, renal cortex, and brain. Lead accumulation was restricted to the red pulp in the spleen. With regard to species differences in lead distribution patterns, it is noteworthy that intensive lead accumulation was observed in the arterial walls only in the kites. In addition, the distribution of copper in the brain was altered in the lead-exposed ducks. Thus, the present study shows suborgan lead distribution in lead-exposed birds and its differences between avian species for the first time. These findings will provide fundamental information to understand the cellular processes of lead poisoning and the mechanisms of species differences in susceptibility to lead exposure.
• The impact of elevated blood lead levels in children on maternal health-related quality of life
  Nakata Hokuto; Tohyama Harukazu; Fujita Wakako; Fujita Wakako; Nakayama Shouta M.M.; Ishizuka Mayumi; Yabe John; Munyinda Nosiku S.; Sakala Doreen; Choongo Kennedy; Choongo Kennedy; Yamasaki Shojiro; Nagai Natsumi; Yoshida Takahiko; Saito Takeshi
  Chemosphere, 279, 130490, 130490, 2021, [International Magazine]
  English, Scientific journal, Kabwe is a mining town in Zambia that has been ranked among "the ten most polluted places in the world" with previous findings of serious lead (Pb) pollution. In this study, we aim to examine the impact of childhood Pb poisoning on the health-related quality of life (HRQoL) of mothers in Kabwe. The HRQoL was assessed using the Short-Form 36 survey for 404 mothers coming from residences in 40 randomly selected standard enumeration areas (SEAs). Blood lead levels (BLLs) of the household members including the mothers themselves were measured. We found a significant positive correlation between the BLLs of the mothers and their children (R = 0.6385, p < 0.0001), while the BLLs of preschool-aged and school-aged children were significantly higher than those of their mothers and fathers. Using the data sets containing the BLLs of the household members, the age of the mothers, the household income, and the household SEA, we performed stepwise multiple linear regression analyses. The results showed significant negative associations between the representative BLL of household children and the BLL of preschool-aged children with the vitality and mental health scores of their mothers. Additionally, the BLL of school-aged children was only significantly associated with the mental health score of their mothers. By contrast, there was a significant negative association between the BLLs of the mothers with the social role functioning score. This suggests that elevated BLLs in children have a negative impact on the mental health conditions of their mothers regardless of the mothers' BLL.
• Bioaccumulation of DDT and other organochlorine pesticides in amphibians from two conservation areas within malaria risk regions of South Africa
  Wolmarans Nico J.; Wolmarans Nico J.; Bervoets Lieven; Gerber Ruan; Yohannes Yared Beyene; Nakayama Shouta MM.; Ikenaka Yoshinori; Ikenaka Yoshinori; Ishizuka Mayumi; Meire Patrick; Smit Nico J.; Wepener Victor; Wepener Victor
  Chemosphere, 274, 129956, 129956, 2021, [International Magazine]
  English, Scientific journal, The threat to wildlife from chemical exposure exists regardless of the presence of conservation boundaries. An issue exacerbated by the use of environmentally persistent insecticides for vector control and long-range transport of legacy persistent organic pollutants. In this comparative study between two important conservation regions in South Africa, Kruger National Park (KNP) and Ndumo Game Reserve (NGR), we assessed organochlorine pesticide (OCP) accumulation in several anuran species collected from within the conservation regions. The two conservation regions differ in size and subsequent proximity of collection sites to OCP input sources. Detectable concentrations of OCPs were present in ∼ half the frogs analysed from KNP and ∼all frogs from NGR and total OCP loads were similar between regions, where measured in the same species. The OCP profiles in KNP frogs were representative of legacy pesticides likely introduced via long-range transport, whereas NGR profiles showed influence of current use of DDT consistent with close proximity to sources. This indicates amphibians can accumulate OCPs within conservation regions and that the exposure of non-target organisms inside conservation regions to current use pesticides has a strong association with proximity to sources. These results serve to inform conservation management decision making with regard to the non-target organism effects of chemical interventions such as vector control pesticide use in and around conservation regions.
• Interspecies differences in cytochrome P450-mediated metabolism of neonicotinoids among cats, dogs, rats, and humans
  Khidkhan Kraisiri; Ikenaka Yoshinori; Ikenaka Yoshinori; Ichise Takahiro; Nakayama Shouta M.M.; Mizukawa Hazuki; Mizukawa Hazuki; Nomiyama Kei; Iwata Hisato; Arizono Koji; Takahashi Keisuke; Kato Keisuke; Ishizuka Mayumi
  Comparative Biochemistry and Physiology. C. Toxicology & Pharmacology, 239, 108898, 108898, 2021, [International Magazine]
  English, Neonicotinoid insecticides are used for agricultural and non-agricultural purposes worldwide. Pets are directly exposed to neonicotinoids in veterinary products and through environmental contamination. Cytochrome P450 (CYP) is among the most significant xenobiotic metabolizing enzymes that oxidizes several chemicals, including neonicotinoids. However, CYP activities and metabolite compositions of neonicotinoid metabolites are unknown in most domesticated pet species. Our objectives were to reveal the differences in metabolites of neonicotinoids (imidacloprid, clothianidin, and acetamiprid) and CYP activities among common pet species (cats and dogs), humans, and rats. The results indicated that the CYP-mediated neonicotinoid metabolism was different depending on species and each neonicotinoid. Among these four species, the kinetics of imidacloprid metabolism indicated that rats have the highest rate of oxidation of imidacloprid to 4OH-imidacloprid, while the greatest enzyme kinetics of imidacloprid metabolism to 5OH-imidacloprid were found in rats and humans. Clothianidin was rapidly metabolized to 1-methyl-3-nitroguanidine and dm-clothianidin in rats, but cats and humans showed the lowest formation of dm-clothianidin. CYP activities in metabolism of acetamiprid to dm-acetamiprid and N-acetyl-acetamiprid were determined to be significantly higher in humans compared to other species. However, further studies should be targeted at identifying the differences in hepatic metabolism of neonicotinoids in these species using recombinant CYP enzymes.
• Clinical biochemical parameters associated with the exposure to multiple environmental metals in residents from Kabwe, Zambia.
  Hokuto Nakata; Shouta M M Nakayama; John Yabe; Kaampwe Muzandu; Haruya Toyomaki; Yared Beyene Yohannes; Andrew Kataba; Golden Zyambo; Yoshinori Ikenaka; Kennedy Choongo; Mayumi Ishizuka
  Chemosphere, 262, 127788, 127788, Jan. 2021, [International Magazine]
  English, Scientific journal, Lead (Pb) interferes with various bodily functions. Although high blood Pb (Pb-B) levels in residents from Kabwe, Zambia have been reported, the accumulation pattern of other metals remains unknown. The study was designed to determine the Pb-B, blood cadmium (Cd-B), and zinc (Zn-B) values of 504 representative samples from Kabwe, as well as the potential associated adverse health effects. The Pb-B level ranged from 0.79 to 154.75 μg/dL and generally increased in areas near the mine. A significant elevation of Cd-B was observed in two areas (0.37 ± 0.26 and 0.32 ± 0.30 μg/L) where the two highest mean Pb-B levels were recorded. By contrast, the Zn-B values did not differ greatly with respect to area. Some blood biochemical parameters relating to hepatic and renal functions were out of the normal range in approximately 20-50% of studied adult participants. The δ-aminolevulinic acid dehydratase (δ-ALAD) activity was significantly inhibited in the two areas contaminated by Pb and Cd. A significant negative relationship was observed between metal levels and clinical parameters, e.g., between Pb-B and δ-ALAD for all the age categories and between Cd-B and the estimated glomerular filtration rate for all the age categories except 0-4 years. The elevated Cd-B in areas near the mine relative to the other areas suggested the potential adverse health effects of Cd and/or the interaction of Pb and Cd. A significant association of metal levels with clinical parameters also indicated the effects of metal exposure on hematopoietic, hepatic, and renal systems.
• Biosorption of Pb (II) and Zn (II) from aqueous solution by Oceanobacillus profundus isolated from an abandoned mine.
  Wilson Mwandira; Kazunori Nakashima; Satoru Kawasaki; Allison Arabelo; Kawawa Banda; Imasiku Nyambe; Meki Chirwa; Mayumi Ito; Tsutomu Sato; Toshifumi Igarashi; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  Scientific reports, 10, 1, 21189, 21189, 03 Dec. 2020, [International Magazine]
  English, Scientific journal, The present study investigated biosorption of Pb (II) and Zn (II) using a heavy metal tolerant bacterium Oceanobacillus profundus KBZ 3-2 isolated from a contaminated site. The effects of process parameters such as effect on bacterial growth, pH and initial lead ion concentration were studied. The results showed that the maximum removal percentage for Pb (II) was 97% at an initial concentration of 50 mg/L whereas maximum removal percentage for Zn (II) was at 54% at an initial concentration of 2 mg/L obtained at pH 6 and 30 °C. The isolated bacteria were found to sequester both Pb (II) and Zn (II) in the extracellular polymeric substance (EPS). The EPS facilitates ion exchange and metal chelation-complexation by virtue of the existence of ionizable functional groups such as carboxyl, sulfate, and phosphate present in the protein and polysaccharides. Therefore, the use of indigenous bacteria in the remediation of contaminated water is an eco-friendly way of solving anthropogenic contamination.
• Land Use in Habitats Affects Metal Concentrations in Wild Lizards Around a Former Lead Mining Site.
  Rio Doya; Shouta M M Nakayama; Hokuto Nakata; Haruya Toyomaki; John Yabe; Kaampwe Muzandu; Yared B Yohannes; Andrew Kataba; Golden Zyambo; Takahiro Ogawa; Yoshitaka Uchida; Yoshinori Ikenaka; Mayumi Ishizuka
  Environmental science & technology, 54, 22, 14474, 14481, 17 Nov. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, We investigated the potential effects of different land use and other environmental factors on animals living in a contaminated environment. The study site in Kabwe, Zambia, is currently undergoing urban expansion, while lead contamination from former mining activities is still prevalent. We focused on a habitat generalist lizards (Trachylepis wahlbergii). The livers, lungs, blood, and stomach contents of 224 lizards were analyzed for their lead, zinc, cadmium, copper, nickel, and arsenic concentrations. Habitat types were categorized based on vegetation data obtained from satellite images. Multiple regression analysis revealed that land use categories of habitats and three other factors significantly affected lead concentrations in the lizards. Further investigation suggested that the lead concentrations in lizards living in bare fields were higher than expected based on the distance from the contaminant source, while those in lizards living in green fields were lower than expected. In addition, the lead concentration of lungs was higher than that of the liver in 19% of the lizards, implying direct exposure to lead via dust inhalation besides digestive exposure. Since vegetation reduces the production of dust from surface soil, it is plausible that dust from the mine is one of the contamination sources and that vegetation can reduce exposure to this.
• Acute exposure to environmentally relevant lead levels induces oxidative stress and neurobehavioral alterations in larval zebrafish (Danio rerio).
  Andrew Kataba; Tarryn L Botha; Shouta M M Nakayama; Yared B Yohannes; Yoshinori Ikenaka; Victor Wepener; Mayumi Ishizuka
  Aquatic toxicology (Amsterdam, Netherlands), 227, 105607, 105607, Oct. 2020, [International Magazine]
  English, Scientific journal, The ubiquitous contamination of environmental lead (Pb) remains a worldwide threat. Improper Pb mine waste disposal from an abandoned lead-zinc mine has recently unearthed widespread Pb poisoning in children in Kabwe Zambia. Although the adverse effects of Pb on human health have begun to receive attention, the ecotoxicological effects on aquatic vertebrates still need further investigation. In addition, there is paucity in the knowledge on the behavioural and molecular subcellular responses in larval zebrafish exposed to Pb within the range of environmental relevant concentration (average 3 μg/L with maximum of 94 μg/L) on aquatic organisms such as zebrafish. The adverse effects of environmentally relevant levels of Pb on larval zebrafish was evaluated by measuring swimming behaviour under alternating dark and light conditions. Larval zebrafish acutely exposed to environmentally relevant Pb exhibited neuro-behavioural alteration including enhanced hyperactivity under light conditions evidenced by increased distanced covered and speed compared to the control. The alteration of entire behavioral profiles was further associated with the disturbed expression patterns of mRNA level of key genes associated with antioxidant (HO-1, Ucp-2 and CoxI), proapoptotic gene (TP53), and antiapoptotic gene (Bcl-2). To our knowledge, this is the first report on the effects of environmentally relevant Pb levels from Kabwe, Zambia and their adverse neurobehavioural effects and subcellular molecular oxidative responses in larval zebrafish acutely exposed within a 30 min period. The current results would be beneficial in our understanding of the effects of low Pb levels acutely discharged into an aquatic environment and the life of aquatic organisms.
• Assessing the population-wide exposure to lead pollution in Kabwe, Zambia: an econometric estimation based on survey data.
  Daichi Yamada; Masato Hiwatari; Peter Hangoma; Daiju Narita; Chrispin Mphuka; Bona Chitah; John Yabe; Shouta M M Nakayama; Hokuto Nakata; Kennedy Choongo; Mayumi Ishizuka
  Scientific reports, 10, 1, 15092, 15092, 15 Sep. 2020, [International Magazine]
  English, Scientific journal, This study quantitatively assessed the population-wide lead poisoning conditions in Kabwe, Zambia, a town with severe lead pollution. While existing data have reported concerning blood lead levels (BLLs) of residents in pollution hotspots, the data representing the entire population are lacking. Further, selection bias is a concern. Given the lack of compulsory testing schemes, BLLs have been observed from voluntary participants in blood sampling surveys, but such data can represent higher or lower BLLs than the population average because of factors simultaneously affecting participation and BLLs. To illustrate the lead poisoning conditions of the population, we expanded the focus of our surveys and then econometrically estimated the BLLs of individuals representing the population, including those not participating in blood sampling, using background geographic, demographic, and socioeconomic information. The estimated population mean BLL was 11.9 μg/dL (11.6-12.1, 95% CI), lower than existing data because of our wide focus and correction of selection bias. However, the scale of lead poisoning remained immense and 74.9% of residents had BLLs greater than 5 μg/dL, the standard reference level for lead poisoning. Our estimates provide a deeper understanding of the problem and a foundation for policy intervention designs.
• Immobilization of Lead and Zinc Leached from Mining Residual Materials in Kabwe, Zambia: Possibility of Chemical Immobilization by Dolomite, Calcined Dolomite, and Magnesium Oxide
  Pawit Tangviroon; Kenta Noto; Toshifumi Igarashi; Takeshi Kawashima; Mayumi Ito; Tsutomu Sato; Walubita Mufalo; Meki Chirwa; Imasiku Nyambe; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  MINERALS, 10, 9, Sep. 2020
  English, Scientific journal
• Blood lead levels and aberrant DNA methylation of the ALAD and p16 gene promoters in children exposed to environmental-lead.
  Yared B Yohannes; Shouta Mm Nakayama; John Yabe; Hokuto Nakata; Haruya Toyomaki; Andrew Kataba; Kaampwe Muzandu; Yoshinori Ikenaka; Kennedy Choongo; Mayumi Ishizuka
  Environmental research, 188, 109759, 109759, Sep. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, BACKGROUND: Lead (Pb) is a well-known toxic heavy metal which can have serious public health hazards. As of today, there is no safe threshold for Pb exposure, especially for children. Lead exposure has been associated with adverse health outcomes involving epigenetic mechanisms, such as aberrant DNA methylation. The objective of the present study was to elucidate the associations between blood lead levels (BLLs) and gene-specific promoter DNA methylation status in environmental Pb-exposed children from Kabwe, Zambia. METHODS: A cross-sectional study was conducted using 2 to 10-year-old children from high Pb exposed area (N = 102) and low Pb exposed area (N = 38). We measured BLLs using a LeadCare II analyzer and investigated the methylation status of the ALAD and p16 gene promoters by methylation-specific PCR. RESULTS: The mean BLLs were 23.7 μg/dL and 7.9 μg/dL in high Pb exposed and low Pb exposed children, respectively. Pb exposure was correlated with increased methylation of the ALAD and p16 genes. The promoter methylation rates of ALAD and p16 in high Pb exposed children were 84.3% and 67.7%, and 42.1% and 44.7% in low Pb exposed children, respectively. Significantly increased methylation was found in both genes in high Pb exposed children compared with low Pb exposed children (p < 0.05). Children with methylated ALAD and p16 genes showed an increased risk of Pb poisoning (odd ratio >1) compared to the unmethylated status. CONCLUSIONS: This study for the first time tries to correlate promoter methylation status of the ALAD and p16 genes in environmental Pb-exposed children from Kabwe, Zambia as a representative. The result suggests that Pb exposure increases aberrations in ALAD and p16 gene methylation, which may be involved in the mechanism of Pb toxicity.
• Relationship between blood test values and blood lead (Pb) levels in Black-headed gull (Chroicocephalus ridibundus: Laridae).
  Nana Ushine; Shouta M M Nakayama; Mayumi Ishizuka; Tatsuo Sato; Yoshihiro Kurahashi; Emu Wakayama; Natsuko Sugiura; Shin-Ichi Hayama
  The Journal of veterinary medical science, 82, 8, 1124, 1129, 19 Aug. 2020, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Few studies have evaluated immunosuppression due to lead accumulation below the overt toxicity threshold. If low levels of lead accumulation cause immunosuppression in birds, those birds could become more susceptible to pathogens. We aimed to determine if low levels of lead accumulation lead to immunosuppression in Black-headed gulls (Chroicocephalus ridibundus). Gulls were captured in Tokyo-bay and Mikawa-bay from January to April 2019. Their blood samples were analyzed for eight items. The data were analyzed to evaluate the correlation between lead concentrations and the variables from each bay. Lead was positively correlated with the percentage of heterophils and heterophil and lymphocyte ratio and negatively with lymphocytes. Thus, low lead accumulation levels may induce changes in percentage of the heterophils and lymphocyte.
• Current situation regarding lead exposure in birds in Japan (2015-2018); lead exposure is still occurring.
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M M Nakayama; Takeshi Kuritani; Mitsuhiro Nakagawa; Keisuke Saito; Yukiko Watanabe; Kohei Ogasawara; Manabu Onuma; Atsushi Haga; Mayumi Ishizuka
  The Journal of veterinary medical science, 82, 8, 1118, 1123, 19 Aug. 2020, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Birds of a number of species have died as a result of lead (Pb) poisoning, including many Steller's sea eagles (Haliaeetus pelagicus) and white-tailed sea eagles (Haliaeetus albicilla) in Hokkaido, the northernmost island of Japan. To address this issue, the use of any type of Pb ammunition for hunting of large animals was prohibited in Hokkaido in 2004. However, Pb poisoning is still being reported in this area, and there are few regulations regarding the use of Pb ammunition in other parts of Japan, where it has been reported that eagles and water birds have been exposed to Pb. This study was performed to accurately determine the current level of Pb exposure of birds found dead in the field or dead in the wild bird centers in Japan (June 2015-May 2018) and to identify the sources of Pb. Pb exposure was found to still be occurring in raptors and water birds in various parts of Japan. Twenty-six point five % and 5.9% of the recorded deaths of Steller's sea eagles and white-tailed sea eagles, respectively, were found to have been poisoned by Pb. In addition, Pb isotope ratio analysis showed that both Pb rifle bullets and Pb shot pellets cause Pb exposure in birds, and these endangered eagles are also exposed to Pb in Hokkaido due to the illegal use of Pb ammunition. Changing to Pb-free ammunition, such as copper (Cu) rifle bullets, steel shot pellets, or bismuth shot pellets, will be essential for the conservation of avian species in Japan.
• Detoxification of lead-bearing zinc plant leach residues from Kabwe, Zambia by coupled extraction-cementation method
  Marthias Silwamba; Mayumi Ito; Naoki Hiroyoshi; Carlito Baltazar Tabelin; Tomoki Fukushima; Ilhwan Park; Sanghee Jeon; Toshifumi Igarashi; Tsutomu Sato; Imasiku Nyambe; Meki Chirwa; Kawawa Banda; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  Journal of Environmental Chemical Engineering, 8, 4, 104197, 104197, Elsevier BV, Aug. 2020, [Peer-reviewed]
  Scientific journal
• Trophic transfer of pollutants within two intertidal rocky shore ecosystems in different biogeographic regions of South Africa.
  Anja Erasmus; Yoshinori Ikenaka; Shouta M M Nakayama; Mayumi Ishizuka; Nico J Smit; Victor Wepener
  Marine pollution bulletin, 157, 111309, 111309, Aug. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Tsitsikamma and Sheffield Beach are two relatively pristine sites along the South African east coast representing warm temperate and subtropical biogeographic rocky shore intertidal ecosystems, respectively. Stable isotopes (δ15N and δ13C), metals and organochlorine pesticides (OCPs) were measured in 38 intertidal components to study biomagnification or biodilution of metals and OCPs in these marine food webs. Comparison of the four species common to both sites revealed that the highest Al, Fe and OCP concentrations were measured in intertidal organisms from Sheffield Beach and was attributed to diffuse input into the nearshore marine environment sources via estuaries and groundwater. All other metals were higher in intertidal organisms from Tsitsikamma and were attributed to the metal-rich phytoplankton blooms during upwelling events. There was no correlation between metal and OCP accumulation and dietary source (δ13C) or trophic level (δ15N). The application of trophic magnification factors (TMFs) using a relatively short benthic food chain indicated biomagnification for As, Cd, Cu, Se and Zn and biodilution of OCPs at both sites. Since these food chains represent only a small portion of the intertidal ecosystems we found limited evidence of biomagnification or biodilution of metals and OCPs across species. This was attributed to different dietary sources in the same food web and similar trophic levels being occupied by the same species in different food chains. We found that food web composition rather than temperature-based biogeographical distribution influenced trophic transfer of metals and OCPs.
• Comparison of two reducing agents dithiothreitol and tris(3-hydroxypropyl)phosphine for in vitro kinetic assay of vitamin K epoxide reductase.
  Kazuki Takeda; Ayuko Morita; Yoshinori Ikenaka; Shouta M M Nakayama; Mayumi Ishizuka
  Veterinary and animal science, 9, 100095, 100095, Jun. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Vitamin K epoxide reductase (VKOR) is a target enzyme for anticoagulants, such as warfarin, that are used as medicines or rodenticides. Assessing VKOR activity is required to ensure the proper usage of these drugs. Dithiothreitol (DTT) is a typical disulfide reductant that is used as a substrate for in vitro VKOR assays. However, DTT is considered problematic because of its side effects. Tris(3-hydroxypropyl)phosphine (THP) has been found to be a reliable alternative to DTT, as shown by kinetic analyses of the VKOR with them. THP showed significantly lower V max and Km values than those of DTT; however, there was no significant difference in their V max/Km and IC50 for warfarin.
• Factors associated with lead (Pb) exposure on dogs around a Pb mining area, Kabwe, Zambia.
  Haruya Toyomaki; John Yabe; Shouta M M Nakayama; Yared B Yohannes; Kaampwe Muzandu; Allan Liazambi; Yoshinori Ikenaka; Takeshi Kuritani; Mitsuhiro Nakagawa; Mayumi Ishizuka
  Chemosphere, 247, 125884, 125884, May 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Lead (Pb)-poisoning is a serious public health concern and dogs have been useful as a sentinel-animal for Pb exposure of humans. In the present study, the blood Pb concentrations (BLC), isotope ratios (208 Pb/206 Pb and 207 Pb/206 Pb), and biochemistry of 120 domestically owned dogs living around a Pb mining area, in Kabwe, Zambia were analyzed to determine factors associated with Pb exposure. The overall mean value of Pb in dog blood in the present study was 271.6 μg/L. The BLC in the dogs from sites near the mine were significantly higher than those in the dogs from a site 4 km from the mine (352.9 ± 205.1 μg/L versus 28.0 ± 13.9 μg/L). BLC significantly decreased with both increasing age of the dogs and distance from the mine. The Pb isotope ratios in the dog that resided near the mine showed values similar to those reported at the galena mine in Kabwe, which is considered to be the source of Pb exposure. In contrast to the high metal exposure that was determined in these dogs, the mean values of most analyzed parameters in the blood biochemical analysis were surprisingly within or close to the standard reference values. Moreover, none of the dogs showed overt signs of Pb-poisoning or other clinical symptoms. The results of analysis of Pb exposure of the dogs obtained in the present study, which are similar to the previously reported results in human in this location, suggest that dogs could be useful as a sentinel animal for Pb exposure of humans in Kabwe.
• Recovery of Lead and Zinc from Zinc Plant Leach Residues by Concurrent Dissolution-Cementation Using Zero-Valent Aluminum in Chloride Medium
  Marthias Silwamba; Mayumi Ito; Naoki Hiroyoshi; Carlito Baltazar Tabelin; Ryota Hashizume; Tomoki Fukushima; Ilhwan Park; Sanghee Jeon; Toshifumi Igarashi; Tsutomu Sato; Meki Chirwa; Kawawa Banda; Imasiku Nyambe; Hokuto Nakata; Shouta Nakayama; Mayumi Ishizuka
  Metals, 10, 4, 531, 531, MDPI AG, 20 Apr. 2020, [Peer-reviewed]
  Scientific journal, Zinc plant leach residues (ZPLRs) contain significant amounts of metal compounds of lead (Pb), zinc (Zn), iron (Fe), etc., hence, they are considered as a secondary source of metals. On the other hand, ZPLRs are regarded as hazardous materials because they contain heavy metals that pollute the environment. Resources and environmental concerns of ZPLRs were addressed in this study by removing/recovering Pb and Zn using a concurrent dissolution and cementation technique. To cement the dissolved Pb and Zn in leaching pulp, zero-valent aluminum (ZVAl) was added during ZPLRs leaching in the hydrochloric (HCl)–sodium chloride (NaCl) solution. The resulting cemented metals were agglomerated and separated by sieving. Lead removal increased with increasing both NaCl and HCl concentrations. However, when ZVAl was added, significant Pb removal was achieved at a low concentration. Zinc was not cemented out of the pulp using ZVAl and its recovery from ZPLRs was dependent on the HCl concentration only. By applying a concurrent dissolution and cementation technique, both Pb and Zn were removed using a low concentration of NaCl, and most importantly Pb—the most toxic metal in ZPLRs—was captured and separated before the solid-liquid separation, hence, eliminating the need for extensive washing of the generated residues to remove the inherent residual solution.
• Quantitative elucidation of maternal-to-fetal transfer of neonicotinoid pesticide clothianidin and its metabolites in mice.
  Shuji Ohno; Yoshinori Ikenaka; Kanoko Onaru; Shizuka Kubo; Nanami Sakata; Tetsushi Hirano; Youhei Mantani; Toshifumi Yokoyama; Keisuke Takahashi; Keisuke Kato; Koji Arizono; Takahiro Ichise; Shouta M M Nakayama; Mayumi Ishizuka; Nobuhiko Hoshi
  Toxicology letters, 322, 32, 38, 01 Apr. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Neonicotinoids (NNs), a widely used class of systemic pesticides, are regarded as exhibiting selective toxicity in insects. However, NNs are suspected of exerting adverse effects on mammals as well, including humans. To date, only adult male animal models have been subjected to general toxicity studies of NNs; fetuses have yet to be considered in this context. Here, we focused on the NN clothianidin (CLO) for the first quantitative LC-MS/MS analysis of maternal-to-fetal transfer and residual property of once-daily (single or multiple days), orally administered CLO and its metabolites in mice. The results revealed the presence of CLO and its five metabolites at approximately the same respective blood levels in both dams and fetuses. In the dams, CLO showed a peak value 1 h after administration, after which levels rapidly decreased at 3 and 6 h. In the fetuses of each group, levels of CLO were almost the same as those observed in the corresponding dams. The present results clearly demonstrated rapid passage of CLO through the placental barrier. However, metabolite-dependent differences observed in blood pharmacokinetics and residual levels. This is the first quantitative demonstration of the presence of CLO and its metabolites in fetal mouse blood.
• Current trends of blood lead levels, distribution patterns and exposure variations among household members in Kabwe, Zambia.
  John Yabe; Shouta Mm Nakayama; Hokuto Nakata; Haruya Toyomaki; Yared B Yohannes; Kaampwe Muzandu; Andrew Kataba; Golden Zyambo; Masato Hiwatari; Daiju Narita; Daichi Yamada; Peter Hangoma; Nosiku Sipilanyambe Munyinda; Tiza Mufune; Yoshinori Ikenaka; Kennedy Choongo; Mayumi Ishizuka
  Chemosphere, 243, 125412, 125412, Mar. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Childhood lead (Pb) poisoning has devastating effects on neurodevelopment and causes overt clinical signs including convulsions and coma. Health effects including hypertension and various reproductive problems have been reported in adults. Historical Pb mining in Zambia's Kabwe town left a legacy of environmental pollution and childhood Pb poisoning. The current study aimed at establishing the extent of Pb poisoning and exposure differences among family members in Kabwe as well as determining populations at risk and identify children eligible for chelation therapy. Blood samples were collected in July and August 2017 from 1190 household members and Pb was measured using a portable LeadCare-II analyser. Participants included 291 younger children (3-months to 3-years-old), 271 older children (4-9-years-old), 412 mothers and 216 fathers from 13 townships with diverse levels of Pb contamination. The Blood Lead Levels (BLL) ranged from 1.65 to 162  μg/dL, with residents from Kasanda (mean 45.7  μg/dL) recording the highest BLL while Hamududu residents recorded the lowest (mean 3.3  μg/dL). Of the total number of children sampled (n = 562), 23% exceeded the 45  μg/dL, the threshold required for chelation therapy. A few children (5) exceeded the 100  μg/dL whereas none of the parents exceeded the 100  μg/dL value. Children had higher BLL than parents, with peak BLL-recorded at the age of 2-years-old. Lead exposure differences in Kabwe were attributed to distance and direction from the mine, with younger children at highest risk. Exposure levels in parents were equally alarming. For prompt diagnosis and treatment, a portable point-of-care devise such as a LeadCare-II would be preferable in Kabwe.
• In Vivo Accumulation of Plastic-Derived Chemicals into Seabird Tissues.
  Kosuke Tanaka; Yutaka Watanuki; Hideshige Takada; Mayumi Ishizuka; Rei Yamashita; Mami Kazama; Nagako Hiki; Fumika Kashiwada; Kaoruko Mizukawa; Hazuki Mizukawa; David Hyrenbach; Michelle Hester; Yoshinori Ikenaka; Shouta M M Nakayama
  Current biology : CB, 30, 4, 723, 728, 24 Feb. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Plastic debris is ubiquitous and increasing in the marine environment [1]. A wide range of marine organisms ingest plastic, and its impacts are of growing concern [2]. Seabirds are particularly susceptible to plastic pollution because of high rates of ingestion [3]. Because marine plastics contain an array of hazardous compounds, the chemical impacts of ingestion are concerning. Several studies on wild seabirds suggested accumulation of plastic-derived chemicals in seabird tissues [4-7]. However, to date, the evidence has all been indirect [4-7], and it is unclear whether plastic debris is the source of these pollutants. To obtain direct evidence for the transfer and accumulation of plastic additives in the tissues of seabirds, we conducted an in vivo plastic feeding experiment. Environmentally relevant exposure of plastics compounded with one flame retardant and four ultraviolet stabilizers to streaked shearwater (Calonectris leucomelas) chicks in semi-field conditions resulted in the accumulation of the additives in liver and adipose fat of 91 to 120,000 times the rate from the natural diet. Additional monitoring of six seabird species detected these chemical additives only in those species with high plastic ingestion rates, suggesting that plastic debris can be a major pathway of chemical pollutants into seabirds. These findings provide direct evidence of seabird exposure to plastic additives and emphasize the role of marine debris ingestion as a source of chemical pollution in marine organisms.
• Avian interspecific differences in VKOR activity and inhibition: Insights from amino acid sequence and mRNA expression ratio of VKORC1 and VKORC1L1.
  Shouta M M Nakayama; Ayuko Morita; Yoshinori Ikenaka; Yusuke K Kawai; Kensuke P Watanabe; Chihiro Ishii; Hazuki Mizukawa; Yared B Yohannes; Keisuke Saito; Yukiko Watanabe; Masaki Ito; Natsuo Ohsawa; Mayumi Ishizuka
  Comparative biochemistry and physiology. Toxicology & pharmacology : CBP, 228, 108635, 108635, Feb. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Worldwide use of anticoagulant rodenticides (ARs) for rodents control has frequently led to secondary poisoning of non-target animals, especially raptors. In order to suggest some factors that may help considering the mechanism of the incidents, this study focused on the avian vitamin K 2, 3-epoxide reductase (VKOR) that is the target protein of ARs. We addressed the interspecific differences in VKOR activity and inhibition related to amino acid sequence and mRNA expression of VKORC1 and VKORC1-like1 (VKORC1L1). Poultry have been considered to be more tolerant to ARs than mammals. However, VKOR activity of owls, hawks, falcon and surprisingly, canaries, was lower and inhibited by warfarin more easily than that of chickens and turkeys. The amino acid sequence of VKORC1 and VKORC1L1 implied that the value of Ki for VKOR activity to ARs could depend on the amino acid at position 140 in the TYX warfarin-binding motif in VKORC1, and other amino acid mutations in VKORC1L1. The mRNA expression ratio of VKORC1:VKORC1L1 differed between turkey (8:1) and chicken (2:3) liver. VKORC1L1 has been reported to be resistant to warfarin compared to VKORC1. Hence, both the Ki of specific VKORC1 and VKORC1L1, and the mRNA expression ratio would cause avian interspecific difference of the VKOR inhibition. Our study also suggested the high inhibition of VKOR activities in raptors and surprisingly that in canaries as well. These factors are the most likely to contribute to the high sensitivity to ARs found in raptors.
• Lead, Zinc and Cadmium Accumulation, and Associated Health Risks, in Maize Grown near the Kabwe Mine in Zambia in Response to Organic and Inorganic Soil Amendments
  Mwilola Patricia N.; Mukumbuta Ikabongo; Mukumbuta Ikabongo; Shitumbanuma Victor; Chishala Benson H.; Uchida Yoshitaka; Nakata Hokuto; Nakayama Shouta; Ishizuka Mayumi
  International Journal of Environmental Research and Public Health (Web), 17, 23, 2020, [International Magazine]
  English, Scientific journal, Health risks due to heavy metal (HM) contamination is of global concern. Despite concerns of high levels of HMs in soils near Kabwe mine in Zambia, edible crop production is common, posing potential health risks. This study assessed the potential of chicken manure (CM), triple superphosphate (TSP) and a blended fertilizer (BF; consisting of Nitrogen, Phosphorous and Potassium (NPK) fertilizer and composted chicken manure) to reduce lead (Pb), zinc (Zn) and cadmium (Cd) in soils and their accumulation in maize grown near the Kabwe mine. Maize was grown to maturity and its HM concentrations and associated health risk indices were calculated. All soil amendments decreased bioavailable soil Pb concentrations by 29-36%, but only CM decreased Zn, while the amendments increased or had no effect on Cd concentrations compared to the control. The amendments reduced Pb (>25%) and Zn concentrations (>18%) in the maize stover and grain. However, Cd concentrations in maize grain increased in the BF and TSP treatments. Bioaccumulation factors showed that Cd had the highest mobility from the soil into maize stover and grain, indicating the need for greater attention on Cd in Kabwe despite its apparently lower soil concentration compared to Pb and Zn. The hazard quotients for Pb and Cd were much greater than one, indicating a high risk of possible exposure to toxic levels by people consuming maize grain grown in this area. This study demonstrated the significant potential of manure and phosphate-based amendments to reduce Pb and Zn, and to some extent Cd, uptake in maize grain and consequently reduce associated health risks.
• Altered hepatic cytochrome P450 expression in cats after chronic exposure to decabromodiphenyl ether (BDE-209)
  KHIDKHAN Kraisiri; MIZUKAWA Hazuki; MIZUKAWA Hazuki; IKENAKA Yoshinori; IKENAKA Yoshinori; NAKAYAMA Shouta M. M.; NOMIYAMA Kei; YOKOYAMA Nozomu; ICHII Osamu; ICHII Osamu; TAKIGUCHI Mitsuyoshi; TANABE Shinsuke; ISHIZUKA Mayumi
  Journal of Veterinary Medical Science (Web), 82, 7, 978, 982, 2020, [Peer-reviewed], [Domestic magazines]
  English, The knowledge of cytochrome P450 (CYP) expression involved in chemical exposure are necessary in clinical applications for the medication and prediction of adverse effects. The aim of this study was to evaluate the mRNA expression of CYP1-CYP3 families in cats exposed to BDE-209 for one year. All selected CYP isoforms showed no significant difference in mRNA expressions between control and exposure groups, however, CYP3A12 and CYP3A131 revealed tend to be two times higher in the exposure group compared to control group. The present results indicate that the chronic exposure of BDE209 could not alter CYP expression in the liver of cats. This result considered caused by the deficiency of CYP2B subfamily which is major metabolism enzyme of polybrominated diphenyl ethers (PBDEs) in cat.
• Bioimaging of Pb and STIM1 in mice liver, kidney and brain using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) and immunohistochemistry.
  Masao Togao; Shouta M M Nakayama; Yoshinori Ikenaka; Hazuki Mizukawa; Yoshiki Makino; Ayano Kubota; Takehisa Matsukawa; Kazuhito Yokoyama; Takafumi Hirata; Mayumi Ishizuka
  Chemosphere, 238, 124581, 124581, Jan. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Lead (Pb) pollution is one of the most serious environmental problems and has attracted worldwide attention. Pb causes hematological, central nervous system, as well as renal toxicity, and so on. Although many investigations about Pb in blood to evaluate pollution status and toxic effects have been reported, there are open question about biological behavior of Pb. In order to reveal any toxicological mechanisms or influences, we focused on the local distribution of Pb in mice organs. Lead acetate (100 mg/L and 1000 mg/L) in drinking water were given to the BALB/c mice (male, seven weeks of age, N = 24) for three weeks. Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) analysis revealed a homogenous distribution of Pb in the liver and inhomogeneous distribution in the kidney and brain. The hippocampus, thalamus, and hypothalamus had higher concentrations than other areas such as the white matter. Surprisingly, in the kidney, Pb tended to accumulate in the medulla rather than the cortex, strongly suggesting that high sensitivity areas and high accumulation areas differ. Moreover, distribution of stromal interacting protein 1 (STIM1) which is candidate gene of Pb pathway to the cells was homogenous in the liver and kidney whereas inhomogeneous in the brain. In contrast to our hypothesis, interestingly, Pb exposure under the current condition did not induce mRNA expressions for any candidate channel or transporter genes. Thus, further study should be conducted to elucidate the local distribution of Pb and other toxic metals, and pathway that Pb takes to the cells.
• Occurrence and concentrations of chemical additives in plastic fragments on a beach on the island of Kauai, Hawaii.
  Kosuke Tanaka; Hideshige Takada; Yoshinori Ikenaka; Shouta M M Nakayama; Mayumi Ishizuka
  Marine pollution bulletin, 150, 110732, 110732, Jan. 2020, [Peer-reviewed], [International Magazine]
  English, Scientific journal, In the ocean, plastic debris containing chemical additives is fragmented into smaller pieces that can be ingested by a wide range of organisms, potentially exposing them to additives. However, the levels of additives retained in marine plastic fragments have rarely been assessed. In this study, 141 plastic fragments from a beach in Kauai were analyzed piece-by-piece for 12 compounds, including UV stabilizers and brominated flame retardants. UV stabilizers (UV-326, UV-328, UV-327, and BP-12) were found in 13% of "small" fragments (4-7 mm) with levels of up to 315 μg/g and in 33% of "large" fragments (15-80 mm) with levels of up to 1130 μg/g. This observation suggests that exhaustive leaching of additives does not occur during fragmentation and that significant levels of additives, comparable to those of the original products, can be retained in fragments of marine plastic, indicating their importance as a vector of chemical additive exposure.
• Dichlorodiphenyltrichloroethane (DDT) levels in rat livers collected from a malaria vector control region.
  Kodai Motohira; Yoshinori Ikenaka; Yared Beyene Yohannes; Shouta M M Nakayama; Victor Wepener; Nico J Smit; Johan H J VAN Vuren; Ana Catarina Sousa; Alex Ajeh Enuneku; Emmanuel Temiotan Ogbomida; Mayumi Ishizuka
  The Journal of veterinary medical science, 81, 11, 1575, 1579, 14 Nov. 2019, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Dichlorodiphenyltrichloroethane (DDT) is an organochlorine insecticide that has been used for indoor residual spraying for the control of mosquito-borne diseases including malaria. However, due to its toxicity and environmental persistence, there are concerns about its potential deleterious effects in humans and wildlife. Therefore, the current study aimed to monitor and estimate the level of DDTs in human communities. The accumulation of DDT and its metabolites was evaluated in house rat (as sentinel) livers collected in an area where DDT was sprayed. DDTs were measured using a gas chromatography / Electron Capture Detector. The results revealed high concentrations of DDTs in the rat livers and the levels of DDTs were similar to findings reported from the same area in 2014.
• Effects of the organochlorine p,p'-DDT on MCF-7 cells: Investigating metabolic and immune modulatory transcriptomic changes.
  Lesa A Thompson; Yoshinori Ikenaka; Wageh Sobhy Darwish; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  Environmental toxicology and pharmacology, 72, 103249, 103249, Nov. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, The organochlorine pesticide dichloro-diphenyl-trichloroethane (DDT) is persistent in the environment and leads to adverse human health effects. High levels in breast milk pose a threat to both breast tissue and nursing infants. The objectives of this study were to investigate DDT-induced transcriptomic alterations in enzymes and transporters involved in xenobiotic metabolism, immune responses, oxidative stress markers, and cell growth in a human breast cancer cell line. MCF-7 cells were exposed to both environmentally-relevant and previously-tested concentrations of p,p'-DDT in a short-term experiment. Significant up-regulation of metabolizing enzymes and transporters (ACHE, GSTO1, NQO1 and ABCC2) and oxidative stress markers (CXCL8, HMOX-1, NFE2L2 and TNF) was clearly observed. Conversely, UGT1A6, AHR and cell growth genes (FGF2 and VEGFA) were severely down-regulated. Identification of these genes helps to identify mechanisms of p,p'-DDT action within cells and may be considered as useful biomarkers for exposure to DDT contamination.
• Effects of PCB exposure on serum thyroid hormone levels in dogs and cats.
  Kohki Takaguchi; Hiroyuki Nishikawa; Hazuki Mizukawa; Rumi Tanoue; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Shouta M M Nakayama; Yoshinori Ikenaka; Tatsuya Kunisue; Mayumi Ishizuka; Shinsuke Tanabe; Hisato Iwata; Kei Nomiyama
  The Science of the total environment, 688, 1172, 1183, 20 Oct. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Polychlorinated biphenyls (PCBs) and their hydroxylated metabolites (OH-PCBs) might disrupt thyroid function. However, there is no clear evidence of PCB exposure disrupting thyroid hormone (TH) homeostasis in dogs and cats. The present study conducted in vivo experiments to evaluate the effects of a mixture of 12 PCB congeners (CB18, 28, 70, 77, 99, 101, 118, 138, 153, 180, 187 and 202, each congener 0.5 mg/kg BW, i.p. administration) on serum TH levels in male dogs (Canis lupus familiaris) and male cats (Felis silvestris catus). In PCB-exposed dogs, the time courses of higher-chlorinated PCBs and L-thyroxine (T4)-like OH-PCBs (4-OH-CB107 and 4-OH-CB202) concentrations were unchanged or tended to increase, whereas those of lower-chlorinated PCBs and OH-PCBs tended to decrease after 24 h. In PCB-exposed cats, concentrations of PCBs increased until 6 h and then remained unchanged. The levels of lower-chlorinated OH-PCBs including 4'-OH-CB18 increased until 96 h and then decreased. In PCB-exposed dogs, free T4 concentrations were higher than those in the control group at 48 and 96 h after PCB administration and positively correlated with the levels of T4-like OH-PCBs, suggesting competitive binding of T4 and T4-like OH-PCBs to a TH transporter, transthyretin. Serum levels of total T4 and total 3,3',5-triiodo-L-thyronine (T3) in PCB-exposed dogs were lower than in the control group at 24 and 48 h and negatively correlated with PCB concentrations, implying that PCB exposure enhanced TH excretion by increasing TH uptake and TH conjugation enzyme activities in the dog liver. In contrast, no obvious changes in TH levels were observed in PCB-exposed cats. This could be explained by the lower levels of T4-like OH-PCBs and lower hepatic conjugation enzyme activities in cats compared with dogs. Different effects on serum TH levels in PCB-exposed dogs and cats are likely to be attributable to species-specific PCB and TH metabolism.
• Bioaccumulation of persistent organic pollutants and their trophic transfer through the food web: Human health risks to the rural communities reliant on fish from South Africa's largest floodplain
  C.M. Volschenk; R. Gerber; M.T. Mkhonto; Y. Ikenaka; Y.B. Yohannes; S. Nakayama; M. Ishizuka; J.H.J. van Vuren; V. Wepener; N.J. Smit
  Science of The Total Environment, 685, 1116, 1126, Elsevier BV, Oct. 2019
  Scientific journal
• How toxic is a non-toxic nanomaterial: Behaviour as an indicator of effect in Danio rerio exposed to nanogold.
  Tarryn L Botha; Sarel J Brand; Yoshinori Ikenaka; Shouta M M Nakayama; Mayumi Ishizuka; Victor Wepener
  Aquatic toxicology (Amsterdam, Netherlands), 215, 105287, 105287, Oct. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Gold nanoparticles are used as drug delivery vectors based on the assumption that they have low toxicity. Literature has, however, produced conflicting results over the last few years. As such, this study aimed to investigate the toxicological effects of nanogold (nAu) on several indicators that range from subcellular to whole-organism level. Gene regulation, changes in oxidative stress biomarkers and swimming performance were assessed in Danio rerio (zebrafish) following exposures to nAu. Adult zebrafish were exposed in vivo to nAu for 96 h and swimming performance measured post-exposure. Liver tissue was collected for DNA microarray and Real-Time Polymerase Chain Reactions (RT-PCR) analyses to determine changes in gene expression (catalase, superoxide dismutase and metallothioneins) and protein biomarker analyses (catalase, superoxide dismutase, acetylcholine esterase, malondialdehyde, cellular energy allocation and metallothionein) were performed on whole-body samples. Swimming behaviour was assessed in 1.1 L Tecniplast™ tanks for a period of six hours and videos were analysed using Noldus EthoVision software. Critical swimming speed was measured in a Loligo® swimming tunnel. The DNA microarray revealed that fish exposed to 20 mg/L differed most from the control group. At 20 mg/L there was a significant increase in gene expression for all genes analysed but this didn't translate to significant responses in protein biomarker levels except for an increase in protein carbonyl formation. The behaviour results demonstrated significant changes in distance moved, swimming speed, acceleration bouts, zone alterations and time spent within the top zone - responses that are usually observed in fish responding to toxicological stress. Furthermore, the critical swimming speed of exposed fish was decreased significantly compared to the control. Since swimming performance and social interaction among zebrafish is essential to their survival, whole-organism behaviour that suggests a toxicological response after exposure to nAu is in agreement with the genetic responses measured in this study.
• One year exposure to Cd- and Pb-contaminated soil causes metal accumulation and alteration of global DNA methylation in rats.
  Shouta M M Nakayama; Hokuto Nakata; Yoshinori Ikenaka; John Yabe; Balazs Oroszlany; Yared B Yohannes; Nesta Bortey-Sam; Kaampwe Muzandu; Kennedy Choongo; Takeshi Kuritani; Mitsuhiro Nakagawa; Mayumi Ishizuka
  Environmental pollution (Barking, Essex : 1987), 252, Pt B, 1267, 1276, Sep. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Metal pollution has been associated with anthropogenic activities, such as effluents and emissions from mines. Soil could be exposure route of wild rats to metals, especially in mining areas. The aim of this study was to verify whether soil exposure under environmentally relevant circumstances results in metal accumulation and epigenetic modifications. Wistar rats were divided to three groups: 1) control without soil exposure, 2) low-metal exposure group exposed to soil containing low metal levels (Pb: 75 mg/kg; Cd: 0.4), and 3) high-metal exposure group exposed to soil (Pb: 3750; Cd: 6). After 1 year of exposure, the metal levels, Pb isotopic values, and molecular indicators were measured. Rats in the high-group showed significantly greater concentrations of Pb and Cd in tissues. Higher accumulation factors (tissue/soil) of Cd than Pb were observed in the liver, kidney, brain, and lung, while the factor of Pb was higher in the tibia. The obtained results of metal accumulation ratios (lung/liver) and stable Pb isotope ratios in the tissues indicated that the respiratory exposure would account for an important share of metal absorption into the body. Genome-wide methylation status and DNA methyltransferase (Dnmt 3a/3b) mRNA expressions in testis were higher in the high-group, suggesting that exposure to soil caused metal accumulation and epigenetic alterations in rats.
• Solidification of sand by Pb(II)-tolerant bacteria for capping mine waste to control metallic dust: Case of the abandoned Kabwe Mine, Zambia.
  Wilson Mwandira; Kazunori Nakashima; Satoru Kawasaki; Mayumi Ito; Tsutomu Sato; Toshifumi Igarashi; Meki Chirwa; Kawawa Banda; Imasiku Nyambe; Shouta Nakayama; Hokuto Nakata; Mayumi Ishizuka
  Chemosphere, 228, 17, 25, Aug. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Environmental impacts resulting from historic lead and zinc mining in Kabwe, Zambia affect human health due to the dust generated from the mine waste that contains lead, a known hazardous pollutant. We employed microbially induced calcium carbonate precipitation (MICP), an alternative capping method, to prevent dust generation and reduce the mobility of contaminants. Pb-resistant Oceanobacillus profundus KBZ 1-3 and O. profundus KBZ 2-5 isolated from Kabwe were used to biocement the sand that would act as a cover to prevent dust and water infiltration. Sand biocemented by KBZ 1-3 and KBZ 2-5 had maximum unconfined compressive strength values of 3.2 MPa and 5.5 MPa, respectively. Additionally, biocemented sand exhibited reduced water permeability values of 9.6 × 10-8 m/s and 8.9 × 10-8 m/s for O. profundus KBZ 1-3 and KBZ 2-5, respectively, which could potentially limit the entrance of water and oxygen into the dump, hence reducing the leaching of heavy metals. We propose that these isolates represent an option for bioremediating contaminated waste by preventing both metallic dust from becoming airborne and rainwater from infiltrating into the waste. O. profundus KBZ 1-3 and O. profundus KBZ 2-5 isolated form Kabwe represent a novel species that has, for the first time, been applied in a bioremediation study.
• Zinc and Lead Biosorption by Oceanobacillus Profundus Kbz 3-2: a Bacterial Strain Resistant to Metals Isolated from Metal polluted Soils in Kabwe, Zambia
  Wilson Mwandira; Kazunori Nakashima; Satoru Kawasaki; Mayumi Ito; Tsutomu Sato; Toshifumi Igarashi; Meki Chirwa; Kawawa Banda; Imasiku Nyambe; Shouta Nakayama; Mayumi Ishizuka
  Proceedings of the 14th Asian Congress on Biotechnology (ACB2019), Jul. 2019, [Peer-reviewed]
  English, International conference proceedings
• ネオニコチノイド系殺虫剤と農薬の現状と今後の展望〜毒性学・農学・行政の視点から〜 ネオニコチノイド系殺虫剤の曝露実態の解明と毒性評価
  池中 良徳; 一瀬 貴大; Nimako Collins; 中山 翔太; 平野 哲史; 市川 剛; 加藤 恵介; 高橋 圭介; 長谷川 浩; 平 久美子; 有薗 幸司; 星 信彦; 藤岡 一俊; 石塚 真由美
  The Journal of Toxicological Sciences, 44, Suppl., S53, S53, (一社)日本毒性学会, Jun. 2019
  Japanese
• Evidence of impacts from DDT in pelican, cormorant, stork, and egret eggs from KwaZulu-Natal, South Africa.
  H Bouwman; Y B Yohannes; S M M Nakayama; K Motohira; M Ishizuka; M S Humphries; V van der Schyff; M du Preez; A Dinkelmann; Y Ikenaka
  Chemosphere, 225, 647, 658, Jun. 2019, [International Magazine]
  English, Scientific journal, DDT remains in use for malaria control in South Africa. We quantified DDTs in aquatic bird eggs from the highly biodiverse northern KwaZulu-Natal, a province of South Africa where DDT has been used for more than 80 years for malaria control. Pelican eggs had the highest ΣDDT concentration (7200 ng/g lipid mass; lm), Little Egret eggs had 6900 ΣDDT lm, African Openbill eggs had 3400 ng/g lm ΣDDT, and White-breasted Cormorant had 2400 ng/g lm. All species had non-significantly different mean concentrations of o,p'-DDT, p,p'-DDT, and ΣDDT, but with significant differences for p,p-DDE, o,p'-DDD, p,p'-DDD, %DDT, %DDD, and %lipid. The thinnest pelican eggshell (0.40 mm) had a ΣDDT concentration of 3300 ng/g lm.; the thickest shell (0.96 mm) had the lowest ΣDDT concentration at 29 ng/g lm; a 58% difference. Linear regressions of concentrations with shell thickness for the pelican eggs were significant for p,p'-DDE and p,p'-DDD, indicating risk of reproductive impairment. Compositional profiles indicate different food webs for the different species. DDT concentrations were lower than from another DDT-sprayed locality in South Africa, possible linked to differences in hydrology and rainfall. We conclude that significant ecotoxic threats associated with DDT remain in this area, and possibly threatens birds from less polluted areas. Our findings suggest continued negative human health and environmental impacts from DDT. There is an urgency to move away from DDT as quickly as possible; alternatively, to implement practices that prevent emissions of DDT to the environment while protecting human life.
• Efficacy of biocementation of lead mine waste from the Kabwe Mine site evaluated using Pararhodobacter sp.
  Wilson Mwandira; Kazunori Nakashima; Satoru Kawasaki; Mayumi Ito; Tsutomu Sato; Toshifumi Igarashi; Kawawa Banda; Meki Chirwa; Imasiku Nyambe; Shouta Nakayama; Mayumi Ishizuka
  Environmental science and pollution research international, 26, 15, 15653, 15664, May 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Biocementation of hazardous waste is used in reducing the mobility of contaminants, but studies on evaluating its efficacy have not been well documented. Therefore, to evaluate the efficacy of this method, physicochemical factors affecting stabilized hazardous products of in situ microbially induced calcium carbonate precipitation (MICP) were determined. The strength and leach resistance were investigated using the bacterium Pararhodobacter sp. Pb-contaminated kiln slag (KS) and leach plant residue (LPR) collected from Kabwe, Zambia, were investigated. Biocemented KS and KS/LPR had leachate Pb concentrations below the detection limit of < 0.001 mg/L, resisted slaking, and had maximum unconfined compressive strengths of 8 MPa for KS and 4 MPa for KS/LPR. Furthermore, biocemented KS and KS/LPR exhibited lower water absorption coefficient values, which could potentially reduce the water transportation of Pb2+. The results of this study show that MICP can reduce Pb2+ mobility in mine wastes. The improved physicochemical properties of the biocemented materials, therefore, indicates that this technique is an effective tool in stabilizing hazardous mine wastes and, consequently, preventing water and soil contamination.
• Characterization of function and genetic feature of UDP-glucuronosyltransferase in avian species
  Yusuke K. Kawai; So Shinya; Yoshinori Ikenaka; Aksorn Saengtienchai; Takamitsu Kondo; Wageh Sobhy Darwish; Shota M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology, 217, 5, 14, Elsevier BV, Mar. 2019
  Scientific journal
• A review: poisoning by anticoagulant rodenticides in non-target animals globally.
  Shouta M M Nakayama; Ayuko Morita; Yoshinori Ikenaka; Hazuki Mizukawa; Mayumi Ishizuka
  The Journal of veterinary medical science, 81, 2, 298, 313, 28 Feb. 2019, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Worldwide use of anticoagulant rodenticides (ARs) for rodents control has frequently led to secondary poisoning of non-target animals, especially raptors. In spite of the occurrence of many incidents of primary or secondary AR-exposure and poisoning of non-target animals, these incidents have been reported only for individual countries, and there has been no comprehensive worldwide study or review. Furthermore, the AR exposure pathway in raptors has not yet been clearly identified. The aim of this review is therefore to comprehensively analyze the global incidence of primary and secondary AR-exposure in non-target animals, and to explore the exposure pathways. We reviewed the published literature, which reported AR residues in the non-target animals between 1998 and 2015, indicated that various raptor species had over 60% AR- detection rate and have a risk of AR poisoning. According to several papers studied on diets of raptor species, although rodents are the most common diets of raptors, some raptor species prey mainly on non-rodents. Therefore, preying on targeted rodents does not necessarily explain all causes of secondary AR-exposure of raptors. Since AR residue-detection was also reported in non-target mammals, birds, reptiles and invertebrates, which are the dominant prey of some raptors, AR residues in these animals, as well as in target rodents, could be the exposure source of ARs to raptors.
• Biotransport of metallic trace elements from marine to terrestrial ecosystems by seabirds
  A. Shoji; K. H. Elliott; S. Aris-Brosou; H. Mizukawa; S. M.M. Nakayama; Y. Ikenaka; M. Ishizuka; T. Kuwae; K. Watanabe; J. Escoruela Gonzalez; Y. Watanuki
  Environmental Toxicology and Chemistry, 38, 1, 106, 114, Jan. 2019
  Scientific journal
• Exposures of children to neonicotinoids in pine wilt disease control areas.
  Yoshinori Ikenaka; Yuichi Miyabara; Takahiro Ichise; Shouta Nakayama; Collins Nimako; Mayumi Ishizuka; Chiharu Tohyama
  Environmental toxicology and chemistry, 38, 1, 71, 79, Jan. 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Neonicotinoid insecticides that have been on the market since 1992 have been used globally including in Japan. Because they are sprayed over forests and agricultural areas, inadvertent toxicity in nontarget insects (especially honey bees) and humans is a matter of public concern. However, information on exposure levels and potential health impacts of neonicotinoids in children living around sprayed areas is scarce. Thus, we determined neonicotinoid exposure levels in children living in communities where thiacloprid was used to control pine wilt disease. A total of 46 children (23 males and 23 females) were recruited for the present study, and informed written consent was obtained from their guardians. Urine specimens were collected before, during, and after insecticide spraying events; and atmospheric particulate matter was also collected. Concentrations of thiacloprid and 6 other neonicotinoid compounds were determined in urine samples and in atmospheric particulate matter specimens using liquid chromatography-electrospray ionization-tandem mass spectrometry. In urine specimens, thiacloprid concentrations were <0.13 μg/L and were detectable in approximately 30% of all samples. Concentrations of the other neonicotinoids, N-dm-acetamiprid, thiamethoxam, dinotefuran, and clothianidin, were 18.7, 1.92, 72.3, and 6.02 µg/L, respectively. Estimated daily intakes of these neonicotinoids were then calculated from urinary levels; although the estimated daily intakes of the neonicotinoids were lower than current acceptable daily intake values, the children were found to be exposed to multiple neonicotinoids on a daily basis. Environ Toxicol Chem 2019;38:71-79. © 2018 SETAC.
• LC-ESI/MS/MS analysis of neonicotinoids in urine of very low birth weight infants at birth.
  Go Ichikawa; Ryota Kuribayashi; Yoshinori Ikenaka; Takahiro Ichise; Shouta M M Nakayama; Mayumi Ishizuka; Kumiko Taira; Kazutoshi Fujioka; Toshimi Sairenchi; Gen Kobashi; Jean-Marc Bonmatin; Shigemi Yoshihara
  PloS one, 14, 7, e0219208, 2019, [Peer-reviewed], [International Magazine]
  English, Scientific journal, OBJECTIVES: Neonicotinoid insecticides are widely used systemic pesticides with nicotinic acetylcholine receptor agonist activity that are a concern as environmental pollutants. Neonicotinoids in humans and the environment have been widely reported, but few studies have examined their presence in fetuses and newborns. The objective of this study is to determine exposure to neonicotinoids and metabolites in very low birth weight (VLBW) infants. METHODS: An analytical method for seven neonicotinoids and one neonicotinoid metabolite, N-desmethylacetamiprid (DMAP), in human urine using LC-ESI/MS/MS was developed. This method was used for analysis of 57 urine samples collected within 48 hours after birth from VLBW infants of gestational age 23-34 weeks (male/female = 36/21, small for gestational age (SGA)/appropriate gestational age (AGA) = 6/51) who were admitted to the neonatal intensive care unit of Dokkyo Hospital from January 2009 to December 2010. Sixty-five samples collected on postnatal day 14 (M/F = 37/22, SGA/AGA = 7/52) were also analyzed. RESULTS: DMAP, a metabolite of acetamiprid, was detected in 14 urine samples collected at birth (24.6%, median level 0.048 ppb) and in 7 samples collected on postnatal day 14 (11.9%, median level 0.09 ppb). The urinary DMAP detection rate and level were higher in SGA than in AGA infants (both p<0.05). There were no correlations between the DMAP level and infant physique indexes (length, height, and head circumference SD scores). CONCLUSION: These results provide the first evidence worldwide of neonicotinoid exposure in newborn babies in the early phase after birth. The findings suggest a need to examine potential neurodevelopmental toxicity of neonicotinoids and metabolites in human fetuses.
• Tissue distribution and characterization of feline cytochrome P450 genes related to polychlorinated biphenyl exposure
  Khidkhan Kraisiri; Mizukawa Hazuki; Mizukawa Hazuki; Ikenaka Yoshinori; Ikenaka Yoshinori; Nakayama Shouta M.M.; Nomiyama Kei; Yokoyama Nozomu; Ichii Osamu; Darwish Wageh Sobhy; Darwish Wageh Sobhy; Takiguchi Mitsuyoshi; Tanabe Shinsuke; Ishizuka Mayumi
  Comparative Biochemistry and Physiology. C. Toxicology & Pharmacology, 226, 108613, 108613, 2019, [Peer-reviewed], [International Magazine]
  English, Cats have been known to be extremely sensitive to chemical exposures. To understand these model species' sensitivity to chemicals and their toxicities, the expression profiles of xenobiotic-metabolizing enzymes should be studied. Unfortunately, the characterization of cytochrome P450 (CYP), the dominant enzyme in phase I metabolism, in cats has not extensively been studied. Polychlorinated biphenyls (PCBs) are known as CYP inducers in animals, but the information regarding the PCB-induced CYP expression in cats is limited. Therefore, in the present study, we aimed to elucidate the mRNA expression of the CYP1-CYP3 families in the cat tissues and to investigate the CYP mRNA expression related to PCB exposure. In cats, the greatest abundance of CYP1-CYP3 (CYP1A2, CYP2A13, CYP2C41, CYP2D6, CYP2E1, CYP2E2, CYP2F2, CYP2F5, CYP2J2, CYP2U1, and CYP3A132) was expressed in the liver, but some extrahepatic isozymes were found in the kidney (CYP1A1), heart (CYP1B1), lung (CYP2B11 and CYP2S1) and small intestine (CYP3A131). In cats, CYP1A1, CYP1A2 and CYP1B1 were significantly upregulated in the liver as well as in several tissues exposed to PCBs, indicating that these CYPs were distinctly induced by PCBs. The strong correlations between 3,3',4,4'-tetrachlorobiphenyl (CB77) and CYP1A1 and CYP1B1 mRNA expressions were noted, demonstrating that CB77 could be a potent CYP1 inducer. In addition, these CYP isoforms could play an essential role in the PCBs biotransformation, particularly 3-4 Cl-PCBs, because a high hydroxylated metabolite level of 3-4 Cl-OH-PCBs was observed in the liver.
• Characterization and imaging of lead distribution in bones of lead-exposed birds by ICP-MS and LA-ICP-MS.
  Chihiro Ishii; Shouta M M Nakayama; Andrew Kataba; Yoshinori Ikenaka; Keisuke Saito; Yukiko Watanabe; Yoshiki Makino; Takehisa Matsukawa; Ayano Kubota; Kazuhito Yokoyama; Hazuki Mizukawa; Takafumi Hirata; Mayumi Ishizuka
  Chemosphere, 212, 994, 1001, Dec. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Lead (Pb) poisoning in raptors and water birds is a serious problem in many countries. However, only a small fraction of Pb poisoning has been detected in birds. Bone specimens may be useful indices of Pb exposure because bones contain ∼90% of the total Pb body burden. The original purpose of this study was to comprehensively analyze Pb accumulation in various bone types using inductively coupled plasma-mass spectrometry (ICP-MS). Since our results showed that Pb accumulation differed greatly depending on bone type, a secondary objective was defined, aiming to investigate the fine Pb distribution and its relation to bone structure and bone marrow by using laser ablation (LA)-ICP-MS. Our findings suggested that bone samples (1) consisting of trabecular tissue and (2) those that contain bone marrow could accumulate high levels of Pb following acute exposure. The shorter turnover time of trabecular bone can cause a rapid accumulation of Pb, and bone marrow may have an important role for internal exposure of Pb to bone tissue. Pb is accumulated in bones via blood flow, and bone marrow receives blood from outside the bones. In conclusion, bone samples provide valuable information on Pb exposure and could be useful to investigate and understand mortalities related to suspected Pb poisoning.
• Comparison of xenobiotic metabolism in phase I oxidation and phase II conjugation between rats and bird species.
  Aksorn Saengtienchai; Yoshinori Ikenaka; Minami Kawata; Yusuke Kawai; Kazuki Takeda; Takamitsu Kondo; Nesta Bortey-Sam; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  Comparative biochemistry and physiology. Toxicology & pharmacology : CBP, 214, 28, 35, Dec. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, There have been many reports regarding toxic chemicals in birds. Chemicals are mainly metabolized in the liver through phase I oxidation by cytochrome P450 (CYP) and phase II conjugation by conjugated enzymes, such as UDP-glucuronosyltransferase (UGT), sulfotransferase (SULT), glutathione-S-transferase (GST), etc. Xenobiotic metabolism differs among bird species, but little detailed information is available. In the present study, the four-ring polycyclic aromatic hydrocarbon (PAH), pyrene, was used as a model xenobiotic to clarify the characteristics of xenobiotic metabolism in birds compared with laboratory animals by in vivo and in vitro studies. Plasma, bile, and excreta (urine and feces) were collected after oral administration of pyrene and analyzed to clarify xenobiotic metabolism ability in chickens and quails. Interestingly, pyrenediol-glucuronide sulfate (PYDOGS) and pyrenediol-diglucuronide (PYDOGG) were present in chickens and quails but not in rats. In addition, the area under the curve (AUC), maximum plasma concentration (Cmax), and time to maximum plasma concentration (Tmax) of pyrene-1-sulfate (PYOS) were higher than those of the parent molecule, pyrene, while the elimination half-life (t1/2) and mean residence time (MRT) were faster than those of the parent pyrene. With regard to sulfation of 1-hydroxypyrene (PYOH), the maximum velocity (Vmax) and Michaelis constant (Km) of rat liver cytosol were greater than those of chicken and quail liver cytosol. Furthermore, Vmax/Km of UGT activity in rat liver microsomes was also greater than those of chicken and quail liver microsomes. Characterization of xenobiotic metabolism revealed species differences between birds and mammals, raising concerns about exposure to various xenobiotics in the environment.
• First report on OH-PAHs in South African Clarias gariepinus bile from an urban impacted system
  W. Pheiffer; N. Bortey-Sam; Y. Ikenaka; S. M.M. Nakayama; H. Mizukawa; M. Ishizuka; N. J. Smit; R. Pieters
  African Journal of Aquatic Science, 43, 3, 305, 312, 25 Sep. 2018
  Scientific journal
• Characterization, Spatial Variation and Risk Assessment of Heavy Metals and a Metalloid in Surface Soils in Obuasi, Ghana.
  Osei Akoto; Nesta Bortey-Sam; Shouta M M Nakayama; Yoshinori Ikenaka; Elvis Baidoo; Joseph Apau; Jemima Tiwaa Marfo; Mayumi Ishizuka
  Journal of health & pollution, 8, 19, 180902, 180902, Sep. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Background: Soil contamination with heavy metals and metalloids has become an increasingly important issue in recent years. Objectives: The present study examines possible contamination of the environment with metals from gold mining activities in Obuasi, Ghana. Methods: Soil samples were collected from commercial and residential areas and tailing dams in Obuasi in order to investigate the extent of lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu), zinc (Zn), cobalt (Co), chromium (Cr), nickel (Ni) and arsenic (As) pollution, create thematic maps showing the extent of heavy metals pollution, identify the sources of pollution, and to assess risks to humans and the surrounding ecological system. Results: Mean concentrations of metals from the study were found in the order of As > Cu > Zn > Cr > Ni > Pb > Co > Hg > Cd. The results showed that all communities were severely polluted with As, and distribution maps highlighted two hot spots at the sulfite treatment plant and Pompura treatment plant tailings dams. Additionally, the levels of Pb, Cu and Zn were elevated around the city center where vehicular traffic is very dense. Principal component analysis indicated that mining activities may have significantly contributed to metal levels in Obuasi soils. The potential ecological risk (RI) indicated that soils in 41% of the communities pose very high risks to the surrounding ecological system, 50% pose considerable risk, and 9% pose a moderate risk. Arsenic and Hg contributed 73 and 15% of the RI, respectively. The average hazard quotient due to soil As exposure was 2.51 ± 1.23 and ingestion of soils in 95% of the communities in the study area could pose non-carcinogenic health risks to children. Moreover, the average cancer risk for children from the communities was 1.13 × 10-3. Based on the United States Environmental Protection Agency (USEPA) recommendation for cancer risk of 10-6 to 10-4, the cancer risk for children (> 10-3) was higher in 45% of the studied communities. Conclusions: The central part of the study area is polluted with Pb, Zn and Cu, and As pollution is severe in all of the studied communities. The RI from all study sites revealed very high risk to the ecological system, including mammals. There could be non-cancer and cancer risks to Obuasi residents due to ingestion of As-contaminated soils, and children are particularly vulnerable. Competing Interests: The author declares no competing financial interests.
• Lead and cadmium excretion in feces and urine of children from polluted townships near a lead-zinc mine in Kabwe, Zambia.
  John Yabe; Shouta M M Nakayama; Yoshinori Ikenaka; Yared B Yohannes; Nesta Bortey-Sam; Abel Nketani Kabalo; John Ntapisha; Hazuki Mizukawa; Takashi Umemura; Mayumi Ishizuka
  Chemosphere, 202, 48, 55, Jul. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Lead (Pb) and cadmium (Cd) are toxic metals that exist ubiquitously in the environment. Children in polluted areas are particularly vulnerable to metal exposure, where clinical signs and symptoms could be nonspecific. Absorbed metals are excreted primarily in urine and reflect exposure from all sources. We analyzed Pb and Cd concentrations in blood, feces and urine of children from polluted townships near a lead-zinc mine in Kabwe, Zambia, to determine concurrent childhood exposure to the metals. Moreover, the study determined the Pb and Cd relationships among urine, feces and blood as well as accessed the potential of urine and fecal analysis for biomonitoring of Pb and Cd exposure in children. Fecal Pb (up to 2252 mg/kg, dry weight) and urine Pb (up to 2914 μg/L) were extremely high. Concentrations of Cd in blood (Cd-B) of up to 7.7 μg/L, fecal (up to 4.49 mg/kg, dry weight) and urine (up to 18.1 μg/L) samples were elevated. metal levels were higher in younger children (0-3 years old) than older children (4-7). Positive correlations were recorded for Pb and Cd among blood, urine and fecal samples whereas negative correlations were recorded with age. These findings indicate children are exposed to both metals at their current home environment. Moreover, urine and feces could be useful for biomonitoring of metals due to their strong relationships with blood levels. There is need to conduct a clinical evaluation of the affected children to fully appreciate the health impact of these metal exposure.
• Investigation of hepatic warfarin metabolism activity in rodenticide-resistant black rats (Rattus rattus) in Tokyo by in situ liver perfusion.
  Kazuki Takeda; Yoshinori Ikenaka; Kazuyuki D Tanaka; Shouta M M Nakayama; Tsutomu Tanikawa; Hazuki Mizukawa; Mayumi Ishizuka
  Pesticide biochemistry and physiology, 148, 42, 49, Jun. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Anti-blood coagulation rodenticides, such as warfarin, have been used all over the world. They inhibit vitamin K epoxide reductase (VKOR), which is necessary for producing several blood clotting factors. This inhibition by rodenticides results in lethal hemorrhage in rodents. However, heavy usage of these agents has led to the appearance of rodenticide-resistant rats. There are two major mechanisms underlying this resistance, i.e., mutation of the target enzyme of warfarin, VKOR, and enhanced metabolism of warfarin. However, there have been few studies regarding the hepatic metabolism of warfarin, which should be related to resistance. To investigate warfarin metabolism in resistant rats, in situ liver perfusion of warfarin was performed with resistant black rats (Rattus rattus) from Tokyo, Japan. Liver perfusion is an in situ methodology that can reveal hepatic function specifically with natural composition of the liver. The results indicated enhanced hepatic warfarin hydroxylation activity compared with sensitive black rats. On the other hand, in an in vitro microsomal warfarin metabolism assay to investigate kinetic parameters of cytochrome P450, which plays a major role in warfarin hydroxylation, the Vmax of resistant rats was slightly but significantly higher compared to the results obtained in the in situ study. These results indicated that another factor like electron donators may also contribute to the enhanced metabolism in addition to high expression of cytochrome P450.
• A glycomics approach to discover novel renal biomarkers in birds by administration of cisplatin and diclofenac to chickens
  C. Ishii; Y. Ikenaka; O. Ichii; S. M.M. Nakayama; S. I. Nishimura; T. Ohashi; M. Tanaka; H. Mizukawa; M. Ishizuka
  Poultry Science, 97, 5, 1722, 1729, May 2018
  Scientific journal
• Human Health Risk from Consumption of Marine Fish Contaminated with DDT and Its Metabolites in Maputo Bay, Mozambique.
  L A Thompson; Y Ikenaka; Y B Yohannes; T Ichise; G Ito; N Bortey-Sam; J J van Vuren; V Wepener; N J Smit; W S Darwish; S M M Nakayama; H Mizukawa; M Ishizuka
  Bulletin of environmental contamination and toxicology, 100, 5, 672, 676, May 2018, [International Magazine]
  English, Scientific journal, Many countries with incidence of malaria, including those surrounding Maputo Bay, use dichloro-diphenyl-trichloroethane (DDT) to reduce mosquitoes. This study is the first to estimate the human health risk associated with consumption of marine fish from Maputo Bay contaminated with DDTs. The median for ∑DDTs was 3.8 ng/g ww (maximum 280.9 ng/g ww). The overall hazard ratio for samples was 1.5 at the 75th percentile concentration and 28.2 at the 95th percentile. These calculations show increased potential cancer risks due to contamination by DDTs, data which will help policy makers perform a risk-benefit analysis of DDT use in malaria control programs in the region.
• Accumulation patterns and risk assessment of metals and metalloid in muscle and offal of free-range chickens, cattle and goat in Benin City, Nigeria.
  Emmanuel Temiotan Ogbomida; Shouta M M Nakayama; Nesta Bortey-Sam; Balazs Oroszlany; Isioma Tongo; Alex Ajeh Enuneku; Ogbeide Ozekeke; Martins Oshioriamhe Ainerua; Iriagbonse Priscillia Fasipe; Lawrence Ikechukwu Ezemonye; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  Ecotoxicology and environmental safety, 151, 98, 108, 30 Apr. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, The use of free range animals for monitoring environmental health offers opportunities to detect exposure and assess the toxicological effects of pollutants in terrestrial ecosystems. Potential human health risk of dietary intake of metals and metalloid via consumption of offal and muscle of free range chicken, cattle and goats by the urban population in Benin City was evaluated. Muscle, gizzard, liver and kidney samples were analyzed for Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, and Pb concentrations using inductively coupled plasma mass spectrometer (ICP-MS) while Hg was determined using Hg analyzer. Mean concentrations of metals (mg/kg ww) varied significantly depending upon the tissues and animal species. Human health risk estimations for children and adults showed estimated daily intake (EDI) values of tissues below oral reference dose (RfD) threshold for non essential metals Cd, As, Pb and Hg thus strongly indicating no possible health risk via consumption of animal based food. Calculated Hazard quotient (THQ) was less than 1 (< 1) for all the metals analyzed for both adult and children. However, Cd and As had the highest value of THQ suggestive of possible health risk associated with continuous consumption of Cd and As contaminated animal based foods. Hazard Index (HI) for additive effect of metals was higher in chicken liver and gizzard for children and chicken liver for adults. Thus, HI indicated that chicken liver and gizzard may contribute significantly to adult and children dietary exposure to heavy metals. Principal component analysis (PCA) showed a clear species difference in metal accumulation between chickens and the ruminants. This study provides baseline data for future studies and also valuable evidence of anthropogenic impacts necessary to initiate national and international policies for control of heavy metal and metalloid content in food items.
• Association between human exposure to heavy metals/metalloid and occurrences of respiratory diseases, lipid peroxidation and DNA damage in Kumasi, Ghana.
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M M Nakayama; Kwadwo A Asante; Elvis Baidoo; Christian Obirikorang; Hazuki Mizukawa; Mayumi Ishizuka
  Environmental pollution (Barking, Essex : 1987), 235, 163, 170, Apr. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Heavy metals and metalloids contamination in soils, water, food and livers of wild rats have been studied in Kumasi, Ghana and despite the estimated risks to residents, there is no epidemiological study to ascertain these projections. In addition, the World Health Organization and International Agency for Research on Cancer have reported an increase in respiratory diseases and cancers, in Ghana. The study's purpose was therefore to explore the potential associations between metal exposure and occurrences of respiratory diseases, lipid peroxidation and/or DNA damage to different age groups and sexes in Kumasi. Human urine was collected from the general population in urban and control sites in Kumasi and nine metals were measured in each sample. Results showed that although Zn was the most abundant total urinary As concentration was higher in 83% of samples compared to reference values. Urinary concentrations of metals, malondialdehyde (MDA) and 8-hydroxy-2-deoxy-guanosine (8-OHdG) were higher in urban sites compared to the control site. Based on the results obtained, there was no significant correlation between urinary metals and age. However, urinary Cd and MDA were highest in age groups 61-85 and 3-20 years, respectively. Significantly higher levels of urinary Co, As and Cd were detected in female participants. The study revealed that exposure to As was significantly associated with increased odds of asthma (odds ratio (OR) = 2.76; CI: 1.11-6.83) and tachycardia (OR = 3.93; CI: 1.01-15.4). Significant association was observed between urinary metals and MDA and 8-OHdG indicating possibility of lipid peroxidation and/or DNA damage in Kumasi residents.
• Sex and site differences in urinary excretion of conjugated pyrene metabolites in the West African Shorthorn cattle.
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M M Nakayama; Jemima T Marfo; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  The Journal of veterinary medical science, 80, 2, 375, 381, 02 Mar. 2018, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Industrialization, economic and population growth rates in Ghana have increased the release of contaminants including polycyclic aromatic hydrocarbons (PAHs) into the environment through which humans and animals are exposed. Cattle is reported to be exposed to high levels of PAHs through feed and inhalation. Once exposed, PAHs are metabolized and excreted in urine, feces or bile. In a previous study, cattle in Ghana was reported to excrete high levels of 1-hydroxypyrene (1-OHPyr) due to high exposure to the parent compound, pyrene. 1-OHPyr is further metabolized to glucuronide and sulfate conjugates. Thus, the aim of this study was to investigate the sex and site differences in urinary excretion of conjugated pyrene metabolites using cattle urine collected from rural and urban sites of the Ashanti region, Ghana. From the results, geometric mean concentration adjusted by specific gravity indicated that 1-OHPyreneGlucuronide (PyG) was the most abundant conjugate followed by PyrenediolSulfate (M3). The sum of conjugated pyrene metabolites and sum of both conjugated and deconjugated pyrene metabolites correlated significantly with PyG, PydiolSulfate (M2) and PydiolSulfate (M3). The study revealed no significant difference in urinary excretion of conjugated pyrene metabolites between rural and urban sites. This indicated that similar to urban sites, cattle in rural sites were exposed to high levels of pyrene. There was no significant difference in urinary concentrations of conjugated pyrene metabolites between sexes.
• β-carotene and retinol reduce benzo[a]pyrene-induced mutagenicity and oxidative stress via transcriptional modulation of xenobiotic metabolizing enzymes in human HepG2 cell line.
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta Nakayama; Hazuki Mizukawa; Lesa A Thompson; Mayumi Ishizuka
  Environmental science and pollution research international, 25, 7, 6320, 6328, Mar. 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Benzo[a]pyrene (B[a]P) is one of the polycyclic aromatic hydrocarbons which is formed due to smoking of foods, incomplete combustion of woods, vehicle exhausts, and cigarettes smokes. B[a]P gets entry into human and animal bodies mainly through their diets. Metabolic activation of B[a]P is required to induce mutagenesis and carcinogenesis in animal and human studies. Carotenoids and retinoids are phytochemicals that if ingested have multiple physiological interferences in the human and animal bodies. In this study, we firstly investigated the protective effects of β-carotene, β-apo-8-carotenal, retinol, and retinoic acid against B[a]P-induced mutagenicity and oxidative stress in human HepG2 cells. Secondly, we tested the hypothesis of modulating xenobiotic metabolizing enzymes (XMEs) by carotenoids and retinoids as a possible mechanism of protection by these micronutrients against B[a]P adverse effects. The obtained results declared that β-carotene and retinol significantly reduced B[a]P-induced mutagenicity and oxidative stress. Tested carotenoids and retinoids reduced B[a]P-induced phase I XMEs and induced B[a]P reduced phase II and III XMEs. Thus, the protective effects of these micronutrients are probably due to their ability of induction of phase II and III enzymes and interference with the induction of phase I enzymes by the promutagen, B[a]P. It is highly recommended to consume foods rich in these micronutrients in the areas of high PAH pollution.
• Contamination by neonicotinoid insecticides and their metabolites in Sri Lankan black tea leaves and Japanese green tea leaves.
  Yoshinori Ikenaka; Kazutoshi Fujioka; Tomonori Kawakami; Takahiro Ichise; Nesta Bortey-Sam; Shouta M M Nakayama; Hazuki Mizukawa; Kumiko Taira; Keisuke Takahashi; Keisuke Kato; Koji Arizono; Mayumi Ishizuka
  Toxicology reports, 5, 744, 749, 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Tea is one of the world's most popular beverages due to health promoting effects. Despite these, there have been concerns about the adverse effects of tea contamination by neonicotinoid insecticides. Only a handful of studies on neonicotinoid insecticides in tea have been carried out and this study was therefore performed to determine the concentrations of seven neonicotinoid insecticides and 20 metabolites in Japanese green tea leaves, and black tea leaves from Sri Lanka; and assess the Maximum Daily Intake (MDI) of neonicotinoid insecticides. From the results, the seven parent compounds were detected in Japanese tea leaves and beverages. Dinotefuran (3004 ng/g) was found at the highest level in green tea leaves. Ten of the 20 metabolites were detected in Japanese tea products. Dinotefuran-urea (92%) and thiacloprid-amide (89%) were most frequently detected in Japanese tea leaves. Clothianidin-urea (100 ng/g) was found at the highest level in green tea leaves. Neonicotinoid insecticides and metabolites were not detected in Sri Lankan black tea leaves. The concentrations and MDI of neonicotinoid insecticides in tea leaves were below the Maximum Residual Levels (MRLs) and Acceptable Daily Intakes (ADIs), respectively.
• Investigation of mRNA expression changes associated with field exposure to DDTs in chickens from KwaZulu-Natal, South Africa.
  Lesa A Thompson; Yoshinori Ikenaka; Wageh S Darwish; Yared B Yohannes; Johan J van Vuren; Victor Wepener; Nico J Smit; Atnafu G Assefa; Ahmed Tharwat; Walaa Fathy Saad Eldin; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  PloS one, 13, 10, e0204400, 2018, [Peer-reviewed], [International Magazine]
  English, Scientific journal, The objective of this study was to identify potential mRNA expression changes in chicken livers associated with environmental exposure to dichloro-diphenyl-trichloroethane (DDT) and its metabolites (DDTs). In particular, we focused on genes relating to the immune system and metabolism. We analyzed liver samples from free-ranging chickens in KwaZulu-Natal, South Africa, for contamination by DDTs. This area predominantly uses DDT in its malaria control program, and homes are sprayed annually with the pesticide. Genes relating to the immune system and metabolism were selected as potential genetic biomarkers that could be linked to higher contamination with DDTs. RT-qPCR analysis on 39 samples showed strong correlations between DDTs contamination and mRNA expression for the following genes: AvBD1, AvBD2, AvBD6 and AvBD7 (down-regulated), and CYP17, ELOVL2 and SQLE (up-regulated). This study shows for the first time interesting and significant correlations between genetic material collected from environmentally-exposed chickens and mRNA expression of several genes involved in immunity and metabolism. These findings show the usefulness of analysis on field samples from a region with high levels of environmental contamination in detecting potential biomarkers of exposure. In particular, we observed clear effects from DDT contamination on mRNA expression of genes involved in immune suppression, endocrine-disrupting effects, and lipid dysregulation. These results are of interest in guiding future studies to further elucidate the pathways involved in and clinical importance of toxicity associated with DDT exposure from contaminated environments, to ascertain the health risk to livestock and any subsequent risks to food security for people.
• Concentrations and human health risk assessment of DDT and its metabolites in free-range and commercial chicken products from KwaZulu-Natal, South Africa
  L. A. Thompson; Y. Ikenaka; Y. B. Yohannes; J. J. van Vuren; V. Wepener; N. J. Smit; W. S. Darwish; S. M. M. Nakayama; H. Mizukawa; M. Ishizuka
  Food Additives & Contaminants: Part A, 34, 11, 1959, 1969, Informa UK Limited, 02 Nov. 2017
  Scientific journal
• Lead exposure in raptors from Japan and source identification using Pb stable isotope ratios.
  Chihiro Ishii; Shouta M M Nakayama; Yoshinori Ikenaka; Hokuto Nakata; Keisuke Saito; Yukiko Watanabe; Hazuki Mizukawa; Shinsuke Tanabe; Kei Nomiyama; Terutake Hayashi; Mayumi Ishizuka
  Chemosphere, 186, 367, 373, Nov. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan. We measured hepatic and renal Pb concentrations and hepatic Pb isotope ratios of Steller's sea eagles (Haliaeetus pelagicus), white-tailed sea eagles (Haliaeetus albicilla), golden eagles (Aquila chrysaetos), and 13 other species (total 177 individuals) that were found dead, as well as blood samples from three eagles found in a weakened state during 1993-2015 from Hokkaido (northern part), Honshu (the main island), and Shikoku (a southern island) of Japan. In the present study in Hokkaido, one quarter of the sea eagles showed a high Pb concentration, suggesting exposure to abnormally high Pb levels and Pb poisoning. Pb isotope ratios indicated that endangered Steller's sea eagle and white-tailed sea eagle were poisoned by Pb ammunition that was used illegally in Hokkaido. In other areas of Japan, both surveillance and regulations were less extensive than in Hokkaido, but Pb poisoning in raptors was also noted. Therefore, Pb poisoning is still a serious problem in raptors in various areas of Japan due to accidental ingestion of materials containing Pb, especially Pb ammunition.
• Anthropogenic and Naturally Produced Brominated Phenols in Pet Blood and Pet Food in Japan.
  Hazuki Mizukawa; Kei Nomiyama; Susumu Nakatsu; Miyuki Yamamoto; Mayumi Ishizuka; Yoshinori Ikenaka; Shouta M M Nakayama; Shinsuke Tanabe
  Environmental science & technology, 51, 19, 11354, 11362, 03 Oct. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Present study determined concentrations and residue patterns of bromophenols (BPhs) in whole blood samples of pet cats and pet dogs collected from veterinary hospitals in Japan. BPhs concentrations were higher in cat blood than in dog blood, with statistically insignificant differences (p = 0.07). Among the congeners, 2,4,6-tribromophenol (TBPh) constituted the majority of BPhs (>90%) detected in both species. Analysis of commercial pet food to estimate exposure routes showed that the most abundant congener in all pet food samples was 2,4,6-TBPh, accounting for >99% of total BPhs. This profile is quite similar to the blood samples of the pets, suggesting that diet might be an important exposure route for BPhs in pets. After incubation in polybrominated diphenyl ether (PBDE) mixtures (BDE-47, BDE-99 and BDE-209), 2,4,5-TBPh was found in dog liver microsomes but not in cat liver microsomes, implying species-specific metabolic capacities for PBDEs. Formation of 2,4,5-TBPh occurred by hydroxylation at the 1' carbon atom of the ether bond of BDE-99 is similar to human study reported previously. Hydroxylated PBDEs were not detected in cats or dogs; therefore, diphenyl ether bond cleavage of PBDEs can also be an important metabolic pathway for BPhs formation in cats and dogs.
• Assessment of DDT contamination in house rat as a possible bioindicator in DDT-sprayed areas from Ethiopia and South Africa.
  Yared Beyene Yohannes; Yoshinori Ikenaka; Gengo Ito; Shouta M M Nakayama; Hazuki Mizukawa; Victor Wepener; Nico J Smit; Johan H J Van Vuren; Mayumi Ishizuka
  Environmental science and pollution research international, 24, 30, 23763, 23770, Oct. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Ethiopia and South Africa are among the few countries to still implement indoor residual spraying with dichloro-diphenyl-trichloroethane (DDT) for malaria vector control. In this study, we investigated the levels and ecological risks of DDT and its metabolites in liver tissues of house rat, as a sentinel animal, for providing an early warning system for public health and wildlife intervention from Ethiopia and South Africa. The results showed that ΣDDT concentration ranged from 127 to 9155 μg/kg wet weight, and the distribution order of DDT and its metabolites in the analyzed liver samples was p,p'-DDD > p,p'-DDE > p,p'-DDT, o,p'-DDT, and o,p'-DDD. The risk assessment indicated a potential adverse impact on humans, especially for pregnant women and children, because they spend majority of their time in a DDT-sprayed house. The ecological assessment also showed a concern for birds of prey and amphibians like frogs. This study is the first report on DDT contamination in liver tissues of house rats from Ethiopia and South Africa, and henceforth, the data will serve as a reference data for future studies.
• Oxidative stress and respiratory symptoms due to human exposure to polycyclic aromatic hydrocarbons (PAHs) in Kumasi, Ghana.
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M M Nakayama; Kwadwo A Asante; Elvis Baidoo; Christian Obirikorang; Aksorn Saengtienchai; Norikazu Isoda; Collins Nimako; Hazuki Mizukawa; Mayumi Ishizuka
  Environmental pollution (Barking, Essex : 1987), 228, 311, 320, Sep. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Studies of polycyclic aromatic hydrocarbons (PAHs) and its metabolites in PM10, soils, rat livers and cattle urine in Kumasi, Ghana, revealed high concentrations and cancer potency. In addition, WHO and IARC have reported an increase in cancer incidence and respiratory diseases in Ghana. Human urine were therefore collected from urban and control sites to: assess the health effects associated with PAHs exposure using malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG); identify any association between OH-PAHs, MDA, 8-OHdG with age and sex; and determine the relationship between PAHs exposure and occurrence of respiratory diseases. From the results, urinary concentrations of the sum of OH-PAHs (∑OHPAHs) were significantly higher from urban sites compared to the control site. Geometric mean concentrations adjusted by specific gravity, GMSG, indicated 2-OHNaphthalene (2-OHNap) (6.01 ± 4.21 ng/mL) as the most abundant OH-PAH, and exposure could be through the use of naphthalene-containing-mothballs in drinking water purification, insect repellent, freshener in clothes and/or "treatment of various ailments". The study revealed that exposure to naphthalene significantly increases the occurrence of persistent cough (OR = 2.68, CI: 1.43-5.05), persistent headache (OR = 1.82, CI: 1.02-3.26), tachycardia (OR = 3.36, CI: 1.39-8.10) and dyspnea (OR = 3.07, CI: 1.27-7.43) in Kumasi residents. Highest level of urinary 2-OHNap (224 ng/mL) was detected in a female, who reported symptoms of persistent cough, headache, tachycardia, nasal congestion and inflammation, all of which are symptoms of naphthalene exposure according to USEPA. The ∑OHPAHs, 2-OHNap, 2-3-OHFluorenes, and -OHPhenanthrenes showed a significantly positive correlation with MDA and 4-OHPhenanthrene with 8-OHdG, indicating possible lipid peroxidation/cell damage or degenerative disease in some participants. MDA and 8-OHdG were highest in age group 21-60. The present study showed a significant sex difference with higher levels of urinary OH-PAHs in females than males.
• Contamination Levels and Sources of Heavy Metals and a Metalloid in Surface Soils in the Kumasi Metropolis, Ghana.
  Osei Akoto; Nesta Bortey-Sam; Yoshinori Ikenaka; Shouta M M Nakayama; Elvis Baidoo; Yared Beyene Yohannes; Mayumi Ishizuka
  Journal of health & pollution, 7, 15, 28, 39, Sep. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Background: Environmental contamination with heavy metals and metalloids due to industrial, smelting and mining activities have become common in large and growing cities. Kumasi is one of the most industrialized cities in Ghana and experiences metal pollution due to recent and past activities. Although metals are naturally abundant in the area, their accumulation in soils could potentially lead to adverse effects on local ecosystems. Objectives: The aims of this study were to determine the distribution, enrichment, geoaccumulation and sources of metals in Kumasi soils and to estimate the contamination factor (CF) and pollution load index (PLI) of these metals in soils. Methods: Concentrations of eight heavy metals and a metalloid were determined in 112 soil samples randomly collected from 31 sampling sites in the area. In addition, 5 soil samples were collected from a pristine site (Kwame Nkrumah University of Science and Technology Botanical Gardens) for data comparison, to determine the local background values for metal concentrations and to evaluate the extent of metal pollution in the study area. Results: Heavy metals such as zinc (Zn), lead (Pb), cadmium (Cd) and chromium (Cr) were enriched in 65, 32, 58 and 93% of the sampling sites, respectively, and geo-accumulation indexes for Cr, Zn, Cd, mercury (Hg) and Pb showed moderate to extreme contamination in 100, 97, 77, 65 and 45% of the sampling sites, respectively. Principal component and cluster analyses revealed that industrial activities including mining were the major sources of metals in Kumasi soils with high metal input in the community of Suame. Distribution maps revealed hotspots of Cd, nickel (Ni), arsenic (As), cobalt (Co), copper (Cu) and Pb in Suame. The highest CFs for Cu, Cd, Ni, As, Co and Pb highlighted anthropogenic inputs in Suame, while Hg was highest in Mbrom, Zn in Suntreso, and Cr in Aboabo. Conclusions: The PLI of metals revealed Suame as the most polluted study site, while Anomangye and Bomso were the least polluted.
• Sediment Metal Contamination in the Kafue River of Zambia and Ecological Risk Assessment.
  Ethel M'kandawire; Kennedy Choongo; John Yabe; Maxwell Mwase; Ngonda Saasa; Shouta M M Nakayama; Nesta Bortey-Sam; Claudia A Blindauer
  Bulletin of environmental contamination and toxicology, 99, 1, 108, 116, Jul. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Zambia's Kafue River receives wastes from various sources, resulting in metal pollution. This study determined the degree of contamination of 13 metals (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Hg and Pb) in Kafue River sediment and the associated ecological risks at six sites in three different seasons. The level of contamination for most metals showed significant site and seasonal differences. The contamination factor and pollution load index indicated that concentrations of most metals particularly copper (Cu), cobalt (Co), manganese (Mn) and arsenic (As) were very high at sites within the Copperbelt mining area. The geoaccumulation index showed an absence of anthropogenic enrichment with Cd and Hg at all the study sites and extreme anthropogenic enrichment with Cu at sites in the Copperbelt mining area. Potential ecological risk showed that Cu and As were likely to cause adverse biological effects to aquatic organisms in the Copperbelt mining region of the Kafue River.
• Uridine Diphosphate-Glucuronosyltransferase (UGT) 2B Subfamily Interspecies Differences in Carnivores.
  Takamitsu Kondo; Yoshinori Ikenaka; Shouta M M Nakayama; Yusuke K Kawai; Hazuki Mizukawa; Yoko Mitani; Kei Nomiyama; Shinsuke Tanabe; Mayumi Ishizuka
  Toxicological sciences : an official journal of the Society of Toxicology, 158, 1, 90, 100, 01 Jul. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, UDP-glucuronosyltransferases (UGTs) are among the most important xenobiotic metabolizing enzymes that conjugate a wide range of chemicals. Previous studies showed that Felidae and Pinnipedia species have very low UGT activities toward some phenolic compounds because of the UGT1A6 pseudogene and small numbers of UGT1A isozymes. In addition to the UGT1As, UGT2Bs isozymes also conjugate various endogenous (eg, estrogens, androgens, and bile acids) and exogenous compounds (opioids, non-steroidal anti-inflammatory drugs, and environmental pollutants). However UGT2B activity and genetic background are unknown in carnivore species. Therefore, this study was performed to elucidate the species differences of UGT2Bs. Using typical substrates for UGT2Bs, UGT activity was measured in vitro. In addition, UGT2B genetic features are analyzed in silico. Results of UGT activity measurement indicate marked species differences between dogs and other carnivores (cats, Northern fur seals, Steller sea lions, Harbor seals, and Caspian seals). Dogs have very high Vmax/Km toward estradiol (17-glucuronide), estrone, lorazepam, oxazepam, and temazepam. Conversely, cats and pinniped species (especially Caspian seals and Harbor seals) have very low activities toward these substrates. The results of genetic synteny analysis indicate that Felidae and pinniped species have very small numbers of UGT2B isozymes (one or none) compared with dogs, rodents, and humans. Furthermore, Felidae species have the same nonsense mutation in UGT2B, which suggests that Felidae UGT2B31-like is also a pseudogene in addition to UGT1A6. These findings of lower activity of UGT2B suggest that Felidae and some pinniped species have very low UGT activity toward a wide range of chemicals. These results are important for Felidae and Pinnipedia species that are frequently exposed to drugs and environmental pollutants.
• Contamination status and accumulation characteristics of heavy metals and arsenic in five seabird species from the central Bering Sea.
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M M Nakayama; Hazuki Mizukawa; Yared Beyene Yohannes; Yutaka Watanuki; Masaaki Fukuwaka; Mayumi Ishizuka
  The Journal of veterinary medical science, 79, 4, 807, 814, 20 Apr. 2017, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Seabirds are marine top predators and accumulate high levels of metals and metalloids in their tissues. Contamination by metals in the highly productive offshore region has become a matter of public concern. It is home to 80% of the seabird population in the U.S.A., 95% of northern fur seals (Callorhinus ursinus), and major populations of Steller sea lions (Eumetopias jubatus), walruses (Odobenus rosmarus) and whales. Here, the concentrations of eight heavy metals (Hg, Cd, Cr, Co, Ni, Cu, Zn and Pb) and a metalloid (As) in the liver and kidneys of the northern fulmar (Fulmarus glacialis), thick-billed murre (Uria lomvia), short-tailed shearwater (Puffinus tenuirostris), tufted puffin (Fratercula cirrhata) and horned puffin (Fratercula corniculata) collected in the Bering Sea were measured. As proxies of trophic level and habitat, nitrogen (δ15N) and carbon (δ13C) stable isotope ratios of breast muscles were also measured. Hepatic Hg concentration was high in northern fulmar, whereas Cd level was high in tufted puffin and northern fulmar. The Hg concentration and δ15N value were positively correlated across individual birds, suggesting that Hg uptake was linked to the trophic status of consumed prey. Furthermore, Hg concentration in our study was higher than those of the same species of seabirds collected in 1990.
• Organochlorine pesticide contamination of foods in Africa: incidence and public health significance.
  Lesa A Thompson; Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The Journal of veterinary medical science, 79, 4, 751, 764, 08 Apr. 2017, [Peer-reviewed], [Domestic magazines]
  English, Scientific journal, Organochlorine pesticides (OCPs) have been used worldwide, particularly in Africa, for several decades. Although many are banned, several African countries still use OCPs especially for the prevention and control of malaria. OCPs are characterized by their bio-accumulation in the environment, especially in the food chain, where they find their way into the human body. Despite no clear epidemiological studies confirming hazardous effects of these chemicals on human health, many studies have reported positive associations between the use of OCPs and neurological and reproductive disorders, and cancer risk. There is a clear gap in published reports on OCPs in Africa and their potential health hazards. Thus, the aim of this review is to summarize the incidence of OCP contamination in various foods in Africa, to demonstrate the potential transmission of these chemicals to people and to discuss their possible health hazards.
• Trace Element Contamination in Tissues of Four Bird Species from the Rift Valley Region, Ethiopia.
  Yared Beyene Yohannes; Yoshinori Ikenaka; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  Bulletin of environmental contamination and toxicology, 98, 2, 172, 177, Feb. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal
• Monitoring Lead (Pb) Pollution and Identifying Pb Pollution Sources in Japan Using Stable Pb Isotope Analysis with Kidneys of Wild Rats.
  Hokuto Nakata; Shouta M M Nakayama; Balazs Oroszlany; Yoshinori Ikenaka; Hazuki Mizukawa; Kazuyuki Tanaka; Tsunehito Harunari; Tsutomu Tanikawa; Wageh Sobhy Darwish; Yared B Yohannes; Aksorn Saengtienchai; Mayumi Ishizuka
  International journal of environmental research and public health, 14, 1, 10 Jan. 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Although Japan has been considered to have little lead (Pb) pollution in modern times, the actual pollution situation is unclear. The present study aims to investigate the extent of Pb pollution and to identify the pollution sources in Japan using stable Pb isotope analysis with kidneys of wild rats. Wild brown (Rattus norvegicus, n = 43) and black (R. rattus, n = 98) rats were trapped from various sites in Japan. Mean Pb concentrations in the kidneys of rats from Okinawa (15.58 mg/kg, dry weight), Aichi (10.83), Niigata (10.62), Fukuoka (8.09), Ibaraki (5.06), Kyoto (4.58), Osaka (4.57), Kanagawa (3.42), and Tokyo (3.40) were above the threshold (2.50) for histological kidney changes. Similarly, compared with the previous report, it was regarded that even structural and functional kidney damage as well as neurotoxicity have spread among rats in Japan. Additionally, the possibility of human exposure to a high level of Pb was assumed. In regard to stable Pb isotope analysis, distinctive values of stable Pb isotope ratios (Pb-IRs) were detected in some kidney samples with Pb levels above 5.0 mg/kg. This result indicated that composite factors are involved in Pb pollution. However, the identification of a concrete pollution source has not been accomplished due to limited differences among previously reported values of Pb isotope composition in circulating Pb products. Namely, the current study established the limit of Pb isotope analysis for source identification. Further detailed research about monitoring Pb pollution in Japan and the demonstration of a novel method to identify Pb sources are needed.
• Spatial and temporal profile of cisplatin delivery by ultrasound-assisted intravesical chemotherapy in a bladder cancer model.
  Noboru Sasaki; Kazuhiro Ishi; Nobuki Kudo; Shouta M M Nakayama; Kensuke Nakamura; Keitaro Morishita; Hiroshi Ohta; Mayumi Ishizuka; Mitsuyoshi Takiguchi
  PloS one, 12, 11, e0188093, 2017, [Peer-reviewed], [International Magazine]
  English, Scientific journal, Non-muscle invasive bladder cancer is one of the most common tumors of the urinary tract. Despite the current multimodal therapy, recurrence and progression of disease have been challenging problems. We hereby introduced a new approach, ultrasound-assisted intravesical chemotherapy, intravesical instillation of chemotherapeutic agents and microbubbles followed by ultrasound exposure. We investigated the feasibility of the treatment for non-muscle invasive bladder cancer. In order to evaluate intracellular delivery and cytotoxic effect as a function to the thickness, we performed all experiments using a bladder cancer mimicking 3D culture model. Ultrasound-triggered microbubble cavitation increased both the intracellular platinum concentration and the cytotoxic effect of cisplatin at the thickness of 70 and 122 μm of the culture model. The duration of enhanced cytotoxic effect of cisplatin by ultrasound-triggered microbubble cavitation was approximately 1 hr. Based on the distance and duration of delivery, we further tested the feasibility of repetition of the treatment. Triple treatment increased the effective distance by 1.6-fold. Our results clearly showed spatial and temporal profile of delivery by ultrasound-triggered microbubble cavitation in a tumor-mimicking structure. Furthermore, we demonstrated that the increase in intracellular concentration results in the enhancement of the cytotoxic effect in a structure with the certain thickness. Repetition of ultrasound exposure would be treatment of choice in future clinical application. Our results suggest ultrasound-triggered microbubble cavitation can be repeatable and is promising for the local control of non-muscle invasive bladder cancer.
• Monitoring Lead (Pb) Pollution and Identifying Pb Pollution Sources in Japan Using Stable Pb Isotope Analysis with Kidneys of Wild Rats
  Hokuto Nakata; Shouta M. M. Nakayama; Balazs Oroszlany; Yoshinori Ikenaka; Hazuki Mizukawa; Kazuyuki Tanaka; Tsunehito Harunari; Tsutomu Tanikawa; Wageh Sobhy Darwish; Yared B. Yohannes; Aksorn Saengtienchai; Mayumi Ishizuka
  INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH, 14, 1, Jan. 2017, [Peer-reviewed]
  English, Scientific journal
• Characterization of Species Differences in Xenobiotic Metabolism in Non-experimental Animals.
  Hazuki Mizukawa; Yoshinori Ikenaka; Mayu Kakehi; Shouta Nakayama; Mayumi Ishizuka
  Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan, 137, 3, 257, 263, The Pharmaceutical Society of Japan, 2017, [Peer-reviewed], [Domestic magazines]
  Japanese, Scientific journal, The ability to metabolize xenobiotics in organisms has a wide degree of variation among organisms. This is caused by differences in the pattern of xenobiotic bioaccumulation among organisms, which affects their tolerance. It has been reported in the veterinary field that glucuronidation (UGT) activity in cats, acetylation activity in dogs and sulfation (SULT) activity in pigs are sub-vital in these species, respectively, and require close attention when prescribing the medicine. On the other hand, information about species differences in xenobiotics metabolism remains insufficient, especially in non-experimental animals. In the present study, we tried to elucidate xenobiotic metabolism ability, especially in phase II UGT conjugation of various non-experimental animals, by using newly constructed in vivo, in vitro and genomic techniques. The results indicated that marine mammals (Steller sea lion, northern fur seal, and Caspian seal) showed UGT activity as low as that in cats, which was significantly lower than in rats and dogs. Furthermore, UGT1A6 pseudogenes were found in the Steller sea lion and Northern fur seal; all Otariidae species are thought to have the UGT1A6 pseudogene as well. Environmental pollutants and drugs conjugated by UGT are increasing dramatically in the modern world, and their dispersal into the environment can be of great consequence to Carnivora species, whose low xenobiotic glucuronidation capacity makes them highly sensitive to these compounds.
• DDTs and other organochlorine pesticides in tissues of four bird species from the Rift Valley region, Ethiopia.
  Yared Beyene Yohannes; Yoshinori Ikenaka; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The Science of the total environment, 574, 1389, 1395, 01 Jan. 2017, [Peer-reviewed], [International Magazine]
  English, Despite the presence of a wide variety and number of birds, there is exceedingly little data on organochlorine pesticide (OCP) residues in birds inhabiting in Africa. In the present study, concentrations of dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes, drins, cyclodienes, and hexachlorobenzene were measured in liver, kidney, heart and brain of 4 bird species from the Rift Valley region, Ethiopia. Indoor residual spraying of DDT for malaria vector control, and indiscriminate and illegal use of pesticides underline the relevance of this study. Levels of ΣOCPs ranged from 1.87 to 4586ng/g wet weight, and the scavenger bird species Leptoptilos crumeniferus had the highest level in liver. In all tissues, contamination profiles of OCPs within the species were similar, with DDTs≫other OCPs. Among the DDTs, p,p'-DDE was the most abundant compound and had significantly a higher burden in all tissues. The risk characterization demonstrated potential risks to the studied birds associated with DDE exposure. Maximum hepatic levels of p,p'-DDE exceeded the levels reported to trigger adverse effects. The detection of p,p'-DDT in all bird tissues suggests the release of fresh DDT to the environment. This is the first study to assay OCPs in different tissues of birds from the Ethiopian Rift Valley region, and henceforth the data will serve as a reference data for future studies.
• The African hedgehog (Atelerix albiventris): Low phase I and phase II metabolism activities
  Aksorn Saengtienchai; Yoshinori Ikenaka; Nesta Bortey-Sam; Usuma Jermnark; Hazuki Mizukawa; Yusuke K. Kawai; Shouta M. M. Nakayama; Mayumi Ishizuka
  COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY, 190, 38, 47, Dec. 2016, [Peer-reviewed]
  English, Scientific journal
• Novel revelation of warfarin resistant mechanism in roof rats (Rattus rattus) using pharmacokinetic/pharmacodynamic analysis
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M. M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  PESTICIDE BIOCHEMISTRY AND PHYSIOLOGY, 134, 1, 7, Nov. 2016, [Peer-reviewed]
  English, Scientific journal
• Excretion of polycyclic aromatic hydrocarbon metabolites (OH-PAHs) in cattle urine in Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M. M. Nakayama; Jemima Marfo; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  ENVIRONMENTAL POLLUTION, 218, 331, 337, Nov. 2016, [Peer-reviewed]
  English, Scientific journal
• Characterization of equine cytochrome P450: role of CYP3A in the metabolism of diazepam
  S. M. M. Nakayama; Y. Ikenaka; A. Hayami; H. Mizukawa; W. S. Darwish; K. P. Watanabe; Y. K. Kawai; M. Ishizuka
  JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS, 39, 5, 478, 487, Oct. 2016, [Peer-reviewed]
  English, Scientific journal
• ポリ塩化ビフェニル(PCBs)のin vivo暴露によるネコの異物代謝解明と甲状腺ホルモンへの影響評価
  水川 葉月; 前原 美咲; 横山 望; 市居 修; 滝口 満喜; 野見山 桂; 西川 博之; 池中 良徳; 中山 翔太; 高口 倖暉; 田辺 信介; 石塚 真由美
  The Journal of Toxicological Sciences, 41, Suppl., S215, S215, (一社)日本毒性学会, Jun. 2016, [Peer-reviewed]
  Japanese
• Strain differences in cytochrome P450 mRNA and protein expression, and enzymatic activity among Sprague Dawley, Wistar, Brown Norway and Dark Agouti rats
  Yoshihiro Nishiyama; Shouta M. M. Nakayama; Kensuke P. Watanabe; Yusuke K. Kawai; Marumi Ohno; Yoshinori Ikenaka; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 78, 4, 675, 680, Apr. 2016, [Peer-reviewed]
  English, Scientific journal
• Bioaccumulation and human health risk assessment of DDT and other organochlorine pesticides in an apex aquatic predator from a premier conservation area
  Ruan Gerber; Nico J. Smit; Johan H. J. Van Vuren; Shouta M. M. Nakayama; Yared B. Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Victor Wepener
  SCIENCE OF THE TOTAL ENVIRONMENT, 550, 522, 533, Apr. 2016, [Peer-reviewed]
  English, Scientific journal
• Distribution and health risk assessment of organochlorine pesticides (OCPs) residue in edible cattle tissues from northeastern part of Egypt: High accumulation level of OCPs in tongue
  Abdallah Fikry A. Mahmoud; Yoshinori Ikenaka; Yared B. Yohannes; Wageh S. Darwish; Elsaid A. Eldaly; Alaa Eldin M. A. Morshdy; Shouta M. M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  CHEMOSPHERE, 144, 1365, 1371, Feb. 2016, [Peer-reviewed]
  English, Scientific journal
• beta-carotene and retinol contents in the meat of herbivorous ungulates with a special reference to their public health importance
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Alaa Eldin Morshdy; Kamal Ibrahim Eldesoky; Shouta Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 78, 2, 351, 354, Feb. 2016, [Peer-reviewed]
  English, Scientific journal
• Reliability of stable Pb isotopes to identify Pb sources and verifying biological fractionation of Pb isotopes in goats and chickens
  Hokuto Nakata; Shouta M. M. Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh Sobhy Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  ENVIRONMENTAL POLLUTION, 208, Pt.B, 395, 403, Jan. 2016, [Peer-reviewed]
  English, Scientific journal
• Constitutive Effects of Lead on Aryl Hydrocarbon Receptor Gene Battery and Protection by beta-carotene and Ascorbic Acid in Human HepG2 Cells
  Wageh S. Darwish; Yoshinori Ikenaka; Shouta M. M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  JOURNAL OF FOOD SCIENCE, 81, 1, T275, T281, Jan. 2016, [Peer-reviewed]
  English, Scientific journal
• Organohalogen Compounds in Pet Dog and Cat: Do Pets Biotransform Natural Brominated Products in Food to Harmful Hydroxlated Substances?
  Hazuki Mizukawa; Kei Nomiyama; Susumu Nakatsu; Hisato Iwata; Jean Yoo; Akira Kubota; Miyuki Yamamoto; Mayumi Ishizuka; Yoshinori Ikenaka; Shouta M. M. Nakayama; Tatsuya Kunisue; Shinsuke Tanabe
  ENVIRONMENTAL SCIENCE & TECHNOLOGY, 50, 1, 444, 452, Jan. 2016, [Peer-reviewed]
  English, Scientific journal
• Application of a Sediment Quality Index for the assessment and monitoring of metals and organochlorines in a premier conservation area
  Ruan Gerber; Nico J. Smit; Johan H. J. van Vuren; Shouta M. M. Nakayama; Yared B. Yohannes; Yoshinori Ikenaka; Mayumi Ishizuka; Victor Wepener
  ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 22, 24, 19971, 19989, Dec. 2015, [Peer-reviewed]
  English, Scientific journal
• Accumulation properties of inorganic mercury and organic mercury in the red-crowned crane Grus japonensis in east Hokkaido, Japan
  Hiroki Teraoka; Erika Okamoto; Moe Kudo; Shouta M. M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Tetsuya Endo; Takio Kitazawa; Takeo Hiraga
  ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 122, 557, 564, Dec. 2015, [Peer-reviewed]
  English, Scientific journal
• Relationship between Urinary N-Desmethyl-Acetamiprid and Typical Symptoms including Neurological Findings: A Prevalence Case-Control Study
  Jemima Tiwaa Mario; Kazutoshi Fujioka; Yoshinori Ikenaka; Shouta M. M. Nakayama; Hazuki Mizukawa; Yoshiko Aoyama; Mayumi Ishizuka; Kumiko Taira
  PLOS ONE, 10, 11, e0142172, Nov. 2015, [Peer-reviewed]
  English, Scientific journal
• Mutagenicity of modelled-heat-treated meat extracts: Mutagenicity assay, analysis and mechanism of mutagenesis
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 63, 4, 173, 182, Nov. 2015, [Peer-reviewed]
  English, Scientific journal
• Cytochrome P450-mediated warfarin metabolic ability is not a critical determinant of warfarin sensitivity in avian species: In vitro assays in several birds and in vivo assays in chicken
  Kensuke P. Watanabe; Minami Kawata; Yoshinori Ikenaka; Shouta M. M. Nakayama; Chihiro Ishii; Wageh Sobhi Darwish; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 34, 10, 2328, 2334, Oct. 2015, [Peer-reviewed]
  English, Scientific journal
• Metal extent in blood of livestock from Dandora dumping site, Kenya: Source identification of Pb exposure by stable isotope analysis
  Hokuto Nakata; Shouta M. M. Nakayama; Yoshinori Ikenaka; Hazuki Mizukawa; Chihiro Ishii; Yared B. Yohannes; Satoru Konnai; Wageh Sobhy Darwish; Mayumi Ishizuka
  ENVIRONMENTAL POLLUTION, 205, 8, 15, Oct. 2015, [Peer-reviewed]
  English, Scientific journal
• Characterization and tissue distribution of conjugated metabolites of pyrene in the rat
  Aksorn Saengtienchai; Yoshinori Ikenaka; Wageh Sobhy Darwish; Shouta M. M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 77, 10, 1261, 1267, Oct. 2015, [Peer-reviewed]
  English, Scientific journal
• Uridine Diphosphate-Glucuronosyltransferase (UGT) Xenobiotic Metabolizing Activity and Genetic Evolution in Pinniped Species
  Mayu Kakehi; Yoshinori Ikenaka; Shouta M. M. Nakayama; Yusuke K. Kawai; Kensuke P. Watanabe; Hazuki Mizukawa; Kei Nomiyama; Shinsuke Tanabe; Mayumi Ishizuka
  TOXICOLOGICAL SCIENCES, 147, 2, 360, 369, Oct. 2015, [Peer-reviewed]
  English, Scientific journal
• Ecological Risk of Heavy Metals and a Metalloid in Agricultural Soils in Tarkwa, Ghana
  Nesta Bortey-Sam; Shouta M. M. Nakayama; Osei Akoto; Yoshinori Ikenaka; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka
  INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH, 12, 9, 11448, 11465, Sep. 2015, [Peer-reviewed]
  English, Scientific journal
• Accumulation of Heavy Metals and Metalloid in Foodstuffs from Agricultural Soils around Tarkwa Area in Ghana, and Associated Human Health Risks
  Nesta Bortey-Sam; Shouta M. M. Nakayama; Osei Akoto; Yoshinori Ikenaka; Julius N. Fobil; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka
  INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH, 12, 8, 8811, 8827, Aug. 2015, [Peer-reviewed]
  English, Scientific journal
• Levels, potential sources and human health risk of polycyclic aromatic hydrocarbons (PAHs) in particulate matter (PM10) in Kumasi, Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M. M. Nakayama; Yared Beyene Yohannes; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka
  ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 22, 13, 9658, 9667, Jul. 2015, [Peer-reviewed]
  English, Scientific journal
• Health risk assessment of heavy metals and metalloid in drinking water from communities near gold mines in Tarkwa, Ghana
  Nesta Bortey-Sam; Shouta M. M. Nakayama; Yoshinori Ikenaka; Osei Akoto; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka
  ENVIRONMENTAL MONITORING AND ASSESSMENT, 187, 7, 1, 12, Jul. 2015, [Peer-reviewed]
  English, Scientific journal
• Metabolic Activation of Heterocyclic Amines and Expression of Xenobiotic-Metabolizing Enzymes in the Gastrointestinal Tract of Rats
  Wageh S. Darwish; Shouta M. M. Nakayama; Yuumi Itotani; Marumi Ohno; Yoshinori Ikenaka; Mayumi Ishizuka
  JOURNAL OF FOOD SCIENCE, 80, 7, T1627, T1632, Jul. 2015, [Peer-reviewed]
  English, Scientific journal
• Are red gourami (Colisa labiosa) low xenobiotic metabolizers? Elucidation of in vivo pharmacokinetics of pyrene as a model substrate
  Yoshinori Ikenaka; Shouta M. M. Nakayama; Mami Oguri; Aksorn Saengtienchai; Hazuki Mizukawa; Jun Kobayashi; Wageh Sobhy Darwish; Mayumi Ishizuka
  ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY, 39, 3, 1148, 1153, May 2015, [Peer-reviewed]
  English, Scientific journal
• Partial cloning of CYP2C23a genes and hepatic protein expression in eight representative avian species
  K. P. Watanabe; Y. K. Kawai; S. M. M. Nakayama; Y. Ikenaka; H. Mizukawa; N. Takaesu; M. Ito; S. -I. Ikushiro; T. Sakaki; M. Ishizuka
  JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTICS, 38, 2, 190, 195, Apr. 2015, [Peer-reviewed]
  English, Scientific journal
• Lead poisoning in children from townships in the vicinity of a lead-zinc mine in Kabwe, Zambia
  John Yabe; Shouta M. M. Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Nesta Bortey-Sam; Balazs Oroszlany; Kaampwe Muzandu; Kennedy Choongo; Abel Nketani Kabalo; John Ntapisha; Aaron Mweene; Takashi Umemura; Mayumi Ishizuka
  CHEMOSPHERE, 119, 941, 947, Jan. 2015, [Peer-reviewed]
  English, Scientific journal
• Human health risks from metals and metalloid via consumption of food animals near gold mines in Tarkwa, Ghana: Estimation of the daily intakes and target hazard quotients (THQs)
  Nesta Bortey-Sam; Shouta M. M. Nakayama; Yoshinori Ikenaka; Osei Akoto; Elvis Baidoo; Yared Beyene Yohannes; Hazuki Mizukawa; Mayumi Ishizuka
  ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 111, 160, 167, Jan. 2015, [Peer-reviewed]
  English, Scientific journal
• Occurrence, distribution, sources and toxic potential of polycyclic aromatic hydrocarbons (PAHs) in surface soils from the Kumasi Metropolis, Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Shouta M. M. Nakayama; Osei Akoto; Yared Beyene Yohannes; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka
  SCIENCE OF THE TOTAL ENVIRONMENT, 496, 471, 478, Oct. 2014, [Peer-reviewed]
  English, Scientific journal
• TCDD-induced chick cardiotoxicity is abolished by a selective cyclooxygenase-2 (COX-2) inhibitor NS398
  Nozomi Fujisawa; Shouta M. M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka
  ARCHIVES OF TOXICOLOGY, 88, 9, 1739, 1748, Sep. 2014, [Peer-reviewed]
  English, Scientific journal
• IDENTIFICATION OF INTERSPECIFIC DIFFERENCES IN PHASE II REACTIONS: DETERMINATION OF METABOLITES IN THE URINE OF 16 MAMMALIAN SPECIES EXPOSED TO ENVIRONMENTAL PYRENE
  Aksorn Saengtienchai; Yoshinori Ikenaka; Shouta M. M. Nakayama; Hazuki Mizukawa; Mayu Kakehi; Nesta Bortey-Sam; Wageh Sobhy Darwish; Toshio Tsubota; Masanori Terasaki; Amnart Poapolathep; Mayumi Ishizuka
  ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 33, 9, 2062, 2069, Sep. 2014, [Peer-reviewed]
  English, Scientific journal
• Organochlorine pesticides in bird species and their prey (fish) from the Ethiopian Rift Valley region, Ethiopia
  Yared Beyene Yohannes; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka
  ENVIRONMENTAL POLLUTION, 192, 121, 128, Sep. 2014, [Peer-reviewed]
  English, Scientific journal
• Apoptosis and gene expression in the developing mouse brain of fusarenon-X-treated pregnant mice.
  Samak Sutjarit; Shota M M Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Wijit Banlunara; Worawut Rerkamnuaychoke; Susumu Kumagai; Amnart Poapolathep
  Toxicology letters, 229, 1, 292, 302, 17 Aug. 2014, [Peer-reviewed], [International Magazine]
  English
• Concentrations and human health risk assessment of organochlorine pesticides in edible fish species from a Rift Valley lake-Lake Ziway, Ethiopia
  Yared B. Yohannes; Yoshinori Ikenaka; Aksorn Saengtienchai; Kensuke P. Watanabe; Shouta M. M. Nakayam; Mayumi Ishizuka
  ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 106, 95, 101, Aug. 2014, [Peer-reviewed]
  English, Scientific journal
• Contamination status and possibility of toxic effects of co-planar polychlorinated biphenyls, polycyclic aromatic hydrocarbons, and dichlorodiphenyltrichloroethane in large Japanese field mouse (Apodemus speciosus) collected from Hokkaido and Aomori
  Hazuki Mizukawa; Yoshinori Ikenaka; Shouta M. M. Nakayama; Kentaro Q. Sakamoto; Shoichi Fujita; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 62, 3, 107, 115, Aug. 2014, [Peer-reviewed]
  English, Scientific journal
• Contamination status and accumulation characteristics of metals and a metalloid in birds on Teuri Island, Hokkaido, Japan
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M. M. Nakayama; Yuya Suzuki; Yutaka Watanuki; Yuji Watanabe; Yared Beyene Yohannes; Hazuki Mizukawa; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 62, 3, 143, 149, Aug. 2014, [Peer-reviewed]
  English, Scientific journal
• An Overview on Mycotoxin Contamination of Foods in Africa
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 76, 6, 789, 797, Jun. 2014, [Peer-reviewed]
  English
• The Effect of Copper on the mRNA Expression Profile of Xenobiotic-Metabolizing Enzymes in Cultured Rat H4-II-E Cells
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta Nakayama; Mayumi Ishizuka
  BIOLOGICAL TRACE ELEMENT RESEARCH, 158, 2, 243, 248, May 2014, [Peer-reviewed]
  English, Scientific journal
• Heavy metal contamination of soil and sediment in Zambia
  Yoshinori Ikenaka; Shouta M.M. Nakayama; Kaampwe Muzandu; Kennedy Choongo; Hiroki Teraoka; Naoharu Mizuno; Mayumi Ishizuka
  Heavy Metal Contamination of Water and Soil: Analysis, Assessment, and Remediation Strategies, 109, 128, 01 Jan. 2014
  In book
• SPECIES DIFFERENCE OF WARFARIN SENSITIVITY AMONG BIRDS CAN BE EXPLAINED BY THE TWO ENZYMES, CYTOCHROME P450 AND VITAMIN K EPOXIDE REDUCTASE
  Kensuke P. Watanabe; Yusuke K. Kawai; Minami Kawata; Shouta M. M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka
  DRUG METABOLISM REVIEWS, 45, 92, 92, Jan. 2014, [Peer-reviewed]
  English
• Occurrence, distribution, and ecological risk assessment of DDTs and heavy metals in surface sediments from Lake Awassa-Ethiopian Rift Valley Lake
  Yared Beyene Yohannes; Yoshinori Ikenaka; Aksorn Saengtienchai; Kensuke P. Watanabe; Shouta M. M. Nakayama; Mayumi Ishizuka
  ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH, 20, 12, 8663, 8671, Dec. 2013, [Peer-reviewed]
  English, Scientific journal
• Dioxin Sensitivity-Related Two Critical Amino Acids of Arylhydrocarbon Receptor May Not Correlate with the Taxonomy or Phylogeny in Avian Species
  Nozomi Fujisawa; Yusuke K. Kawai; Shouta M. M. Nakayama; Yoshinori Ikenaka; Hideaki Yamamoto; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 75, 12, 1577, 1583, Dec. 2013, [Peer-reviewed]
  English, Scientific journal
• Repeated Treatment with Furazolidone Induces Multiple Cytochrome P450-Related Activities in Chicken Liver, but Not in Rat Liver
  Nobuo Sasaki; Tomoyuki Matumoto; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka; Akio Kazusaka; Shoichi Fujita
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 75, 11, 1497, 1502, Nov. 2013, [Peer-reviewed]
  English, Scientific journal
• Characterization of phase-II conjugation reaction of polycyclic aromatic hydrocarbons in fish species: unique pyrene metabolism and species specificity observed in fish species.
  Yoshinori Ikenaka; Mami Oguri; Aksorn Saengtienchai; Shouta M M Nakayama; Shigeho Ijiri; Mayumi Ishizuka
  Environmental toxicology and pharmacology, 36, 2, 567, 578, Sep. 2013, [Peer-reviewed], [International Magazine]
  English, Metabolic activity, particularly conjugation, was examined in fish by analyzing pyrene (a four-ring, polycyclic aromatic hydrocarbon) metabolites using high-performance liquid chromatography (HPLC) with fluorescence detector (FD), a mass spectrometry (MS) system, and kinetic analysis of conjugation enzymes. Fourteen fresh water fish species, including Danio rerio and Orizias latipes, were exposed to aqueous pyrene, and the resulting metabolites were collected. Identification of pyrene metabolites by HPLC/FD and ion-trap MS indicated that the major metabolites were pyrene glucuronide and pyrene sulfate in all 14 species. Differences were observed in pyrene glucuronide:pyrene sulfate ratio and in the total amount of pyrene conjugates excreted between fish species. Furthermore, a correlation was found between the amount of pyrene glucuronide present and the total amount of the pyrene metabolite eliminated. Kinetic analysis of conjugation by hepatic microsomes in vitro indicated that the differences in excreted metabolites reflected the differences in enzymatic activities.
• Accumulation and biological effects of metals in wild rats in mining areas of Zambia
  Shouta M. M. Nakayama; Yoshinori Ikenaka; Kyohei Hamada; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Takashi Umemura; Mayumi Ishizuka
  ENVIRONMENTAL MONITORING AND ASSESSMENT, 185, 6, 4907, 4918, Jun. 2013, [Peer-reviewed]
  English, Scientific journal
• Organochlorine pesticides and heavy metals in fish from Lake Awassa, Ethiopia: Insights from stable isotope analysis
  Yared Beyene Yohannes; Yoshinori Ikenaka; Shouta M. M. Nakayama; Aksorn Saengtienchai; Kensuke Watanabe; Mayumi Ishizuka
  CHEMOSPHERE, 91, 6, 857, 863, May 2013, [Peer-reviewed]
  English, Scientific journal
• Antibiotic residues in food: the African scenario
  Wageh Sobhy Darwish; Elsaid A. Eldaly; Mohamed Tharwat E-Abbasy; Yoshinori Ikenaka; Shouta Nakayama; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, Supplement, S13, S22, Feb. 2013, [Peer-reviewed]
  English
• Distribution of metals in organs of Clarias gariepinus, Heterobranchus bidorsalis, and Chrysichthys nigrodigitatus from the Offin River at Dunkwa-on-Offin, Ghana.
  Jemima T Marfo; Osei Akoto; Shouta M M Nakayama; Elvis Baidoo; Yoshinori Ikenaka; Mayumi Ishizuka
  The Japanese journal of veterinary research, 61 Suppl, S69-71, 71, Feb. 2013, [Peer-reviewed], [Domestic magazines]
  English, All heavy metals are potentially harmful to most organisms at some level of exposure and absorption. Concentrations of Co, Cr, Cu, Ni, Zn, Hg, Cd, As, and Pb were determined by atomic absorption spectrophotometry (AAS) in three fish species (C. gariepinus, C. nigrodigitatus, and H. bidorsalis) from the Offin River in Dunkwa township, Ghana. In the fish species, gills, livers, and muscles were analyzed. The metal that recorded the highest concentration was Zn, which was highly accumulated in the liver of C. gariepinus, but had the lowest concentration in the muscles of C. nigrodigitatus.
• Determination of benzo[a]pyrene levels in ambient air and the source of polycyclic aromatic hydrocarbons using a diagnostic ratio method in Ghana
  Nesta Bortey-Sam; Osei Akoto; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, S72, S74, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• Heavy metal pollution in Japanese seabirds
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M. M. Nakayama; Yuya Suzuki; Yutaka Watanuki; Yuji Watanabe; Masa-aki Fukuwaka; Yared B. Yohannes; Yusuke K. Kawai; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, S75, S76, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• Metabolism of pyrene, a polycyclic aromatic hydrocarbon in freshwater turtles
  Balazs Oroszlany; Yoshinori Ikenaka; Aksorn Saengtiengchan; Mami Oguri; Shouta M. M. Nakayama; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, S77, S78, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• Metal contaminated soil from mining area caused metal accumulation and biological responses in rats
  Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Takashi Umemura; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, S79, S81, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• In vitro diazepam metabolism in horses
  Aki Hayami; Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka
  JAPANESE JOURNAL OF VETERINARY RESEARCH, 61, S82, S84, Feb. 2013, [Peer-reviewed]
  English, Scientific journal
• Geographic information system-based source estimation of copper pollution in Lake Itezhi-tezhi and metal-accumulation profiles in Oreochromis spp. from both field and laboratory studies.
  Shouta M M Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Taro Muroya; Shigeho Ijiri; Masao Minagawa; Takashi Umemura; Mayumi Ishizuka
  Archives of environmental contamination and toxicology, 64, 1, 119, 29, 1, Jan. 2013, [Peer-reviewed], [International Magazine]
  English, The Copperbelt region, upstream of the Kafue River, including Lake Itezhi-tezhi (ITT), in Zambia has extensive copper (Cu) mines. In our field study, geographic information system analysis in lake sediment indicated that the northern part of the lake, i.e., the Copperbelt region, could be the source of Cu pollution. Concentrations of Cu in stomach contents between fish species were not significantly different. However, Oreochromis spp. liver showed significantly greater Cu concentrations than those in other fish species. Log liver [Cu], standard length, and nitrogen stable isotope ratio were positively correlated only in Oreochromis spp. In the laboratory study, O. niloticus and O. latipes were exposed to Cu for 4 days, and recovery phases ≤ 28 days were examined. O. niloticus showed significantly greater concentrations of Cu compared with O. latipes at all sampling points. Significantly greater concentrations of Hg in Schilbe intermedius liver than for other fish species were observed, whereas O. macrochir showed significantly greater concentrations of cadmium. In conclusion, the northern part of the lake could be the source of Cu pollution in Lake ITT. Diet may not be the reason for high Cu accumulation in Oreochromis spp. Results from both field and laboratory studies imply that Oreochromis spp. contain high concentrations of Cu under normal physiological conditions.
• Metal distribution in tissues of free-range chickens near a lead-zinc mine in Kabwe, Zambia
  John Yabe; Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Geoffrey Mainda; Matthew Kabeta; Mayumi Ishizuka; Takashi Umemura
  ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 32, 1, 189, 192, Jan. 2013, [Peer-reviewed]
  English, Scientific journal
• Accumulation of Metals in the Liver and Kidneys of Cattle from Agricultural Areas in Lusaka, Zambia
  John Yabe; Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Mayumi Ishizuka; Takashi Umemura
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 74, 10, 1345, 1347, Oct. 2012, [Peer-reviewed]
  English, Scientific journal
• EFFECTS OF ENVIRONMENTAL LEAD CONTAMINATION ON CATTLE IN A LEAD/ZINC MINING AREA: CHANGES IN CATTLE IMMUNE SYSTEMS ON EXPOSURE TO LEAD IN VIVO AND IN VITRO
  Yoshinori Ikenaka; Shouta M. M. Nakayama; Taro Muroya; John Yabe; Satoru Konnai; Wageh Sobhy Darwish; Kaampwe Muzandu; Kennedy Choongo; Geoffrey Mainda; Hiroki Teraoka; Takashi Umemura; Mayumi Ishizuka
  ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 31, 10, 2300, 2305, Oct. 2012, [Peer-reviewed]
  English, Scientific journal
• The nucleotide sequence of metallothioneins (MT) in liver of the Kafue lechwe (Kobus leche kafuensis) and their potential as biomarkers of heavy metal pollution of the Kafue River
  Ethel M'kandawire; Michelo Syakalima; Kaampwe Muzandu; Girja Pandey; Martin Simuunza; Shouta M. M. Nakayama; Yusuke K. Kawai; Yoshinori Ikenaka; Mayumi Ishizuka
  GENE, 506, 2, 310, 316, Sep. 2012, [Peer-reviewed]
  English, Scientific journal
• Metal and metalloid levels and bio-accumulation characteristics in soil, sediment, land plants and hippopotami (Hippopotamus amphibius L) from the South Luangwa National Park, Zambia
  Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Ethel M'kandawire; Jun Yasuda; Mayumi Ishizuka
  ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY, 80, 333, 338, Jun. 2012, [Peer-reviewed]
  English, Scientific journal
• Phase-II conjugation ability for PAH metabolism in amphibians: Characteristics and inter-species differences
  Haruki Ueda; Yoshinori Ikenaka; Shouta M. M. Nakayama; Tomoko Tanaka-Ueno; Mayumi Ishizuka
  AQUATIC TOXICOLOGY, 105, 3-4, 337, 343, Oct. 2011, [Peer-reviewed]
  English, Scientific journal
• UPTAKE OF LEAD, CADMIUM, AND OTHER METALS IN THE LIVER AND KIDNEYS OF CATTLE NEAR A LEAD-ZINC MINE IN KABWE, ZAMBIA
  John Yabe; Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Mayumi Ishizuka; Takashi Umemura
  ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY, 30, 8, 1892, 1897, Aug. 2011, [Peer-reviewed]
  English, Scientific journal
• Metal and metalloid contamination in roadside soil and wild rats around a Pb-Zn mine in Kabwe, Zambia
  Shouta M. M. Nakayama; Yoshinori Ikenaka; Kyohei Hamada; Kaampwe Muzandu; Kennedy Choongo; Hiroki Teraoka; Naoharu Mizuno; Mayumi Ishizuka
  ENVIRONMENTAL POLLUTION, 159, 1, 175, 181, Jan. 2011, [Peer-reviewed]
  English, Scientific journal
• Heavy Metal Accumulation in Lake Sediments, Fish (Oreochromis niloticus and Serranochromis thumbergi), and Crayfish (Cherax quadricarinatus) in Lake Itezhi-tezhi and Lake Kariba, Zambia
  Shouta M. M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Balazs Oroszlany; Hiroki Teraoka; Naoharu Mizuno; Mayumi Ishizuka
  ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 59, 2, 291, 300, Aug. 2010, [Peer-reviewed]
  English, Scientific journal
• Molecular Cloning of Novel Cytochrome P450 1A Genes from Nine Japanese Amphibian Species
  Shouta M. M. Nakayama; Tomoko Tanaka-Ueno; Kentaro Q. Sakamoto; Shoichi Fujita; Mayumi Ishizuka
  JOURNAL OF VETERINARY MEDICAL SCIENCE, 71, 10, 1407, 1411, Oct. 2009, [Peer-reviewed]
  English, Scientific journal

• DRUG METABOLISM AND PHARMACOKINETICS 61 (2025) 101173 ASSESSMENT OF UNINTENTIONAL EFFECTS ON ENDANGERED SPECIES ENDEMIC TO THE BONIN ISLANDS CAUSED BY DEPLOYMENT OF ANTICOAGULANT RODENTICIDE
  Masashi Koide; Yusuke Kawai; Mitsuki Kondo; Yoshiya Odaya; Kazuo Horikoshi; Hajime Suzuki; Takashi Nagamine; Yamiko Nakaya; Yoshinori Ikenaka; Mayumi Ishizuka; Shouta Nakayama, DRUG METABOLISM AND PHARMACOKINETICS, 61, Jun. 2025
  English, Summary international conference
• ゾウのアルコール及び有機リン代謝能:遺伝子発現・酵素動態・構造解析に基づく研究
  森田鮎子; 渡邉可菜実; AMNART Poapolathep; SARANYA Poapolathep; AKSORN Saengtienchai; KRAISIRI Khidkhan; SUPAPHEN Sripiboon; KORNSORN Srikulnath; CHATCHOTE Thitaram; CHALEAMCHAT Somgid; TAWEEPOKE Angkawanish; WARANGKHANA Langkaphin; 近藤充希; 武田一貴; 池中良徳; 池中良徳; 池中良徳; 中山翔太; 中山翔太; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 48th, 2025
• Species-specific and tissue-specific differences in iron stable isotope ratios in vertebrates and implications for iron metabolism
  長谷川菜々子; 長谷川菜々子; 板井啓明; 高橋嘉夫; 伊地知雄太; 柏原輝彦; BEYENE Yared; 国末達也; 小笠原浩平; 徳長ゆり香; 池中良徳; 池中良徳; NDASHE Kunda; KATABA Andrew; 銅谷理緒; 小竹皓貴; 小竹皓貴; 乘本裕明; 乘本裕明; 中山翔太; 中山翔太; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 33rd, 2025
• Py-GC/MSを用いた新規の高感度分析法による海棲哺乳類体内のナノプラスチックモニタリング
  清水菜実; 徳長ゆり香; 田中厚資; 鈴木剛; 国末達也; 田島木綿子; 松石隆; 松田純佳; 松田純佳; ヨハネス ヤレドベイェネ; 池中良徳; 池中良徳; 中山翔太; 石塚真由美, 日本獣医学会学術集会講演要旨集, 168th, 2025
• Analysis of changing metabolomes in the brains ofmice exposed to neonicotinoids using LC/Q-TOF/MS
  小池智也; 江口哲史; 野見山桂; 平野哲史; NIMAKO Collins; YOHANNES Yared Beyene; 中山翔太; 石塚真由美; 池中良徳, 環境化学討論会要旨集(CD-ROM), 33rd, 2025
• 農薬の卵内投与によるニワトリ雛における刷り込みへの影響
  山崎鈴穂; 松島俊也; 松島俊也; 三浦桃子; 丸山瑞貴; ヨハネス ヤレドベイェネ; ヨハネス ヤレドベイェネ; 石塚真由美; 中山翔太; 池中良徳; 池中良徳, 日本獣医学会学術集会講演要旨集, 168th, 2025
• 日本のリス大量死亡事故の原因の究明~殺虫剤の蓄積量と複合毒性の評価~
  後藤美空; ヨハネス ヤレドベイエネ; ヨハネス ヤレドベイエネ; 池中良徳; 中山翔太; 中山翔太; 金子美香子; 石塚真由美, 日本獣医学会学術集会講演要旨集, 168th, 2025
• Analysis of Species Differences in δ-ALAD Activity as a Biomarker for Lead Sensitivity in Avian Species
  丸山瑞貴; 渡邊有希子; 石井千尋; 齊藤慶輔; 牛根奈々; 伊藤真輝; 柿阪圭太; 飯間裕子; 中谷裕美子; 長嶺隆; 銅谷理緒; 小笠原浩平; 池中良徳; 池中良徳; 池中良徳; ベイェネ ヤレド・ヨハネス; ベイェネ ヤレド・ヨハネス; 石塚真由美; 中山翔太; 中山翔太, 環境化学討論会要旨集(CD-ROM), 33rd, 2025
• 北海道・知床半島におけるヒグマの体毛中の水銀濃度
  TAN Joshaniel; 松林良太; 新庄康平; YARED Beyene; 神保美渚; 白根ゆり; 中山翔太; 中山翔太; 池中良徳; 石塚真由美; 坪田敏男; 下鶴倫人; 下鶴倫人, 日本哺乳類学会大会プログラム・講演要旨集, 2025, 2025
• 質量分析計を用いた神経毒性検出に向けたチャレンジ
  池中良徳; 小池智也; 平井杏里; 江口哲史; 野見山桂; 平野哲史; 星信彦; NIMAKO Collins; BEYENE Yared; 中山翔太; 石塚真由美, Journal of Toxicological Sciences (Web), 50, Supplement 1, 2025
• Inter-species variation in iron stable isotope ratios and their association with hepatic ferritin in vertebrates
  長谷川菜々子; 板井啓明; 高橋嘉夫; 伊地知雄太; 柏原輝彦; YOHANNES Yared B.; 国末達也; 小笠原浩平; 徳長ゆり香; 池中良徳; 池中良徳; NDASHE Kunda; KATABA Andrew; 銅谷理緒; 小竹皓貴; 小竹皓貴; 乘本裕明; 乘本裕明; 中山翔太; 中山翔太; 石塚真由美, Biomedical Research on Trace Elements (Web), 36, S1, 2025
• 沖縄島の固有種であるヤンバルクイナにおける抗凝固系殺鼠剤感受性評価
  小間隆央; 小出将士; 近藤充希; 森田鮎子; 中谷裕美子; 長嶺隆; 久保田彰; ヤレド ベイェネ; 池中良徳; 池中良徳; 石塚真由美; 中山翔太; 中山翔太, 日本獣医学会学術集会講演要旨集, 167th, 2024
• マウスにおいて殺虫剤ダイアジノンの曝露がLeptospira interrogans血清群Hebdomadisの尿中排菌量に及ぼす影響
  新屋惣; MUTHUSINGHE Devinda S.; 小泉信夫; 吉松組子; 中山翔太; 石塚真由美; 池中良徳, レプトスピラ・シンポジウム抄録(CD-ROM), 60th, 2024
• Evaluation of unintentional effects on endangered species endemic to the Bonin Islands caused by deployment of anticoagulant rodenticide
  小出将士; 小笠原浩平; 川合佑典; 近藤充希; 小田谷嘉弥; 堀越和夫; 鈴木創; 長嶺隆; 中谷裕美子; 池中良徳; 石塚真由美; 中山翔太; 中山翔太, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• Characterization of xenobiotic metabolism in Hyaenidae by phylogenetic analysis of phase II drug metabolizing enzymes
  宮本汐里; 近藤充希; 森田鮎子; 渡邉可菜実; 銅谷理緒; 池中良徳; 中山翔太; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• Assessing elephant’s ability to metabolize alcohol-transcriptome analysis and in vitro kinetic study on alcohol dehydrogenase
  森田鮎子; 渡邉可菜実; POAPOLATHEP Amnart; POAPOLATHEP Saranya; SAENGTIENCHAI Aksorn; KHIDKHAN Kraisiri; SRIPIBOON Supaphen; SRIKULNATH Kornsorn; THITARAM Chatchote; SOMGID Chaleamchat; ANGKAWANISH Taweepoke; LANGKAPHIN Warangkhana; 近藤充希; 池中良徳; 池中良徳; 中山翔太; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• In Silico Gene Analysis and In Vitro Transcriptome Analysis of Phase 2 Xenobiotic Metabolizing Enzymes in Elephants
  渡邉可菜実; 森田鮎子; POAPOLATHEP Amnart; POAPOLATHEP Saranya; SAENGTIENCHAI Aksorn; KHIDKHAN Kraisiri; SRIPIBOON Supaphen; SRIKULNATH Kornsorn; THITARAM Chatchote; SOMGRID Chaleamchat; ANGKAWANISH Taweepoke; LANGKAPHIN Warangkhana; 近藤充希; 池中良徳; 池中良徳; 中山翔太; 中山翔太; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• Assessment of susceptibility to anticoagulant rodenticides in Okinawa rail, endangered species endemic to the Okinawa Island
  小間隆央; 小出将士; 近藤充希; 森田鮎子; 中谷裕美子; 長嶺隆; 久保田彰; BEYENE Yared; 池中良徳; 池中良徳; 石塚真由美; 中山翔太, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• Elucidation of the biological defense mechanisms of hyenas and other carnivores
  宮本汐里; 近藤充希; 森田鮎子; 渡邉可菜実; 銅谷理緒; 池中良徳; 中山翔太; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• What is lead poisoning in birds?
  石塚真由美; 池中良徳; 中山翔太, Journal of Toxicological Sciences, 49, Supplement (CD-ROM), 2024
• Characteristics of lead toxicity and species differences in birds
  中山翔太; 中山翔太, Journal of Toxicological Sciences, 49, Supplement (CD-ROM), 2024
• Current situation of lead (Pb) pollution of wild bird in Japan, focusing on wild waterfowls
  近藤充希; 大沼学; 中山翔太; 中山翔太; 大田和朋紀; 石塚真由美, Journal of Toxicological Sciences, 49, Supplement (CD-ROM), 2024
• Comparison of sensitivity of avian aminolevulinic acid dehydratase to lead exposure
  丸山瑞貴; 渡邊有希子; 石井千尋; 齊藤慶輔; 牛根奈々; 伊藤真輝; 飯間裕子; 中谷裕美子; 長嶺隆; 銅谷理緒; 小笠原浩平; 池中良徳; BEYENE Yared; 石塚真由美; 中山翔太, 日本野生動物医学会大会・講演要旨集, 30th, 2024
• 鉛曝露に対するヘム合成系酵素の感受性の鳥類種差とその決定要因の検討
  丸山瑞貴; 渡邊有希子; 石井千尋; 齊藤慶輔; 牛根奈々; 伊藤真輝; 銅谷理緒; 小笠原浩平; 池中良徳; ヤレド ベイェネ; 石塚真由美; 中山翔太, 日本鳥学会大会講演要旨集, 2024 (CD-ROM), 2024
• 環境毒性物質が鳥類の腸内細菌叢に与える影響
  小笠原浩平; 矢野琳太郎; 伊藤和顕; 森田鮎子; 小出将士; 徳長ゆり香; 眞下大和; 丸山瑞貴; 池中良徳; 中尾亮; 福間直希; 中山翔太; 石塚真由美, 日本獣医学会学術集会講演要旨集, 167th, 2024
• Influence of environmental toxicants on avian gut microbiome
  小笠原浩平; 矢野琳太郎; 伊藤和顕; 森田鮎子; 小出将士; 徳長ゆり香; 眞下大和; 丸山瑞貴; 池中良徳; 中尾亮; 福間直希; 中山翔太; 石塚真由美, Journal of Toxicological Sciences, 49, Supplement (CD-ROM), 2024
• 鳥類におけるδ-アミノレブリン酸脱水酵素(ALAD)の鉛曝露に対する感受性種差の解明
  丸山瑞貴; 渡邊有希子; 石井千尋; 齊藤慶輔; 牛根奈々; 伊藤真輝; 銅谷理緒; 小笠原浩平; 池中良徳; 池中良徳; 池中良徳; ベイェネ ヤレド; 石塚真由美; 中山翔太; 中山翔太, 日本獣医学会学術集会講演要旨集, 167th, 2024
• Pharmacokinetic and Pharmacodynamic (PK/PD) Analysis to Assess Sensitivity of Wild Roof Rats (Rattus rattus) in the Bonin Islands to Rodenticide Diphacinone
  田中康太郎; 清水敬太; 佐藤美侑; 片山雅史; 中山翔太; 近藤理美; 池中良徳; 一瀬貴大; 石塚真由美; 鎌田亮; 小山田佑輔; 港隆一; 橋本琢磨; 田中和之; 木村悟朗; 谷川力; 加藤恵介; 日下部太一; 武田一貴, 環境化学討論会要旨集(CD-ROM), 32nd, 2024
• 偏微分方程式モデリングを用いた野生動物における抗血液凝固系殺鼠剤体内動態の予測
  深松美咲; 片山雅史; 中山翔太; 宮前萌優; 鎌田亮; 武田一貴, 日本獣医学会学術集会講演要旨集, 167th, 2024
• 規制の対象外となっている狩猟用鉛弾に起因するオジロワシの鉛中毒症事例
  渡辺有希子; 河野晴子; 石井千尋; 丸山瑞貴; 石塚真由美; 中山翔太; 中山翔太; 齊藤慶輔, 日本獣医師会獣医学術学会年次大会講演要旨集, 2023 (Web), 2023
• 規制の対象外となっている狩猟用鉛弾に起因するオジロワシの鉛中毒症事例
  渡辺有希子; 河野晴子; 石井千尋; 丸山瑞貴; 石塚真由美; 中山翔太; 中山翔太; 齊藤慶輔, 北海道獣医師会雑誌, 67, 8, 2023
• Recent occurrence of raptor lead poisoning in Hokkaido
  渡辺有希子; 河野晴子; 石井千尋; 丸山瑞貴; 石塚真由美; 中山翔太; 齊藤慶輔, 日本野生動物医学会大会・講演要旨集, 29th, 2023
• Evaluation of Rodenticide Susceptibility of the Natural Monument; Bonin Flying Fox using AlphaFold2 and Molecular Simulation
  武田一貴; 武田一貴; 川合佑典; 安尾信明; 関嶋政和; 真砂皓大; 池中良徳; 堀越和夫; 鈴木創; 石塚真由美; 中山翔太, 環境化学討論会要旨集(CD-ROM), 31st, 2023
• Effect of diphacinone on immortalized cells from green sea turtle (Chelonia mydas)
  片山雅史; 福田智一; 武田一貴; 近藤理美; 清野透; 中山翔太; 中山翔太, 日本地球惑星科学連合大会予稿集(Web), 2023, 2023
• Comparison of avian gut microbiota between grain- and fish-diet habit
  小笠原浩平; 山田尚輝; 千葉茜; 内田義崇; 境秀文; 竹中康進; 風間健太郎; 風間麻未; 山岸潤也; 池中良徳; 中山翔太; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 29th, 2023
• Evolutionary history of UGT genes involved in xenobiotic metabolism in mammals and birds and their relationship to plants
  川合佑典; 池中良徳; 池中良徳; 生城真一; 西川美宇; 一色乃亜; 武田一貴; 中山翔太; 中山翔太; 久保田彰; 石塚真由美, 日本進化学会大会プログラム・講演要旨集(Web), 25th, 2023
• Establishment of bioresources for evaluation of environmental pollutants in the green sea turtle
  片山雅史; 福田智一; 大沼学; 武田一貴; 近藤理美; 中山翔太; 中山翔太, 日本地球惑星科学連合大会予稿集(Web), 2022, 2022
• メタボロミクスおよび甲状腺ホルモン分析による有機ハロゲン汚染物質への曝露によって引き起こされたペット猫(Felis silvestris catus)の健康影響評価
  野見山 桂; 山本 恭央; 江口 哲史; 西川 博之; 水川 葉月; 横山 望; 市居 修; 滝口 満喜; 中山 翔太; 池中 良徳; 石塚 真由美; 国末 達也, 環境ホルモン学会研究発表会要旨集, 23回, 55, 55, Sep. 2021
  環境ホルモン学会(日本内分泌撹乱化学物質学会), Japanese
• Comprehensive analysis of steroid profile in dogs with Cushing' syndrome and hepatocellular carcinoma(和訳中)
  Oo Thandar; 佐々木 東; 池中 良徳; 永田 矩之; 一瀬 貴大; Bin Teoh Yong; 川元 誠; 小島 一輝; 菅原 芽伊; 中山 翔太; 石塚 真由美; 中村 健介; 滝口 満喜, 日本獣医学会学術集会講演要旨集, 164回, [HSO, 18], Sep. 2021
  (公社)日本獣医学会, English
• Analysis of variation of serum metabolites in cats by BDE209 long-term exposure test using Smart Metabolite Database
  野見山桂; 林多聞; 江口哲史; 水川葉月; 高口倖暉; 横山望; 市居修; 滝口満喜; 笹岡一慶; 中山翔太; 池中良徳; 石塚真由美; 国末達也, 環境化学討論会要旨集(CD-ROM), 29th, 2021
• 液体クロマトグラフィー質量分析法によるアフリカゾウの血中ステロイドホルモン濃度測定法の確立および無排卵雌における排卵誘起の試み
  篠原明; 篠原明; 鳥居佳子; 入江陽一; 牛尾佳名子; 曽地千尋; 宗内一平; 楠田哲士; 東達也; 一瀬貴大; 中山翔太; 石塚真由美; 池中良徳; 片桐成二; 柳川洋二郎, 日本獣医学会学術集会講演要旨集, 164th (CD-ROM), 2021
• 鉛中毒マウスの短期作業記憶低下および血中ステロイドの分析
  村上昂暉; 中山翔太; 一瀬貴大; 中田北斗; YARED B. Yohannes; YARED B. Yohannes; ANDREW Kataba; ANDREW Kataba; 平井杏梨; 池中良徳; 石塚真由美, 日本獣医学会学術集会講演要旨集, 164th (CD-ROM), 2021
• 希少鳥類の鉛毒性に関する基盤技術開発
  石塚真由美; 池中良徳; 石井千尋; 中田北斗; 中山翔太, 日本獣医学会学術集会講演要旨集, 164th (CD-ROM), 2021
• Why wild birds in Japan still suffer from lead poisoning?
  小笠原浩平; 渡辺有希子; 安達光; 河野晴子; 中山翔太; 石井千尋; 池中良徳; 大沼学; 石塚真由美; 齊藤慶輔, 環境ホルモン学会研究発表会プログラム・要旨集, 23rd (Web), 2021
• Toxicity assessment of the neonicotinoid insecticide clothianidin on frogs
  西部詞哉; 池中良徳; 一瀬貴大; 新屋惣; 中山翔太; 石塚真由美, 環境ホルモン学会研究発表会プログラム・要旨集, 23rd (Web), 2021
• Evolutionary analysis of UDP-glucuronosyltransferase genes in vertebrates using a genome database
  川合佑典; 池中良徳; 中山翔太; 久保田彰; 石塚真由美, 環境ホルモン学会研究発表会プログラム・要旨集, 23rd (Web), 2021
• Species differences in xenobiotics metabolism and detoxification-introduction-
  石塚真由美; 中山翔太; 池中良徳, Journal of Toxicological Sciences, 46, Supplement, 2021
• Evaluation of the effects of pesticides on the nervous system~Establishment and application of a highly sensitive analytical method for monoamine neurotransmitters~
  池中良徳; 平井杏里; 野見山桂; 新間秀一; 一瀬貴大; 中山翔太; 石塚真由美, JSBMS Letters, 46, Supplement, 2021
• Elucidation of the pathophysiology of hyperadrenocortical hyperfunction (Cushing’s syndrome) by simultaneous analysis of steroid hormones using LC-MS/MS
  一瀬貴大; 安田淑一; 佐々木東; 滝口満喜; 中山翔太; 石塚真由美; 池中良徳, JSBMS Letters, 46, Supplement, 2021
• The disruption of brain function in mice administered with nicotinic acetylcholine receptor agonists~The development of the detection method using two-photon microscopy~
  平井杏梨; 杉尾翔太; NIMAKO Collins; 中山翔太; 加藤恵介; 高橋圭介; 有薗幸司; 平野哲史; 星信彦; 石塚真由美; 和氣弘明; 池中良徳, 環境化学討論会要旨集(CD-ROM), 29th, 2021
• Evaluation of the ameliorative effect of Spirulina (Arthrospira platensis) supplementation on parameters relating to lead poisoning and obesity in C57BL/6J mice
  Nakata Hokuto; Nakayama Shouta M.M.; Kataba Andrew; Kataba Andrew; Yohannes Yared Beyene; Yohannes Yared Beyene; Ikenaka Yoshinori; Ikenaka Yoshinori; Ishizuka Mayumi, Journal of Functional Foods, 77, 2021
• Estimation of the feeding record of pregnant Antarctic minke whales (Balaenoptera bonaerensis) using carbon and nitrogen stable isotope analysis of baleen plates
  Uchida Mayuka; Suzuki Ippei; Suzuki Ippei; Ito Keizo; Ito Keizo; Ishizuka Mayumi; Ikenaka Yoshinori; Ikenaka Yoshinori; Nakayama Shouta M. M.; Tamura Tsutomu; Konishi Kenji; Bando Takeharu; Mitani Yoko, Polar Biology, 44, 3, 2021
• ニコチン性アセチルコリン受容体アゴニストによるシグナル毒性と2光子顕微鏡を用いた検出手法の開発
  平井 杏梨; 杉尾 翔太; 池中 良徳; Collins Nimako; 中山 翔太; 星 信彦; 和氣 弘明; 石塚 真由美, The Journal of Toxicological Sciences, 45, Suppl., S86, S86, Jun. 2020
  (一社)日本毒性学会, Japanese
• エジプシャンルーセットオオコウモリ(Rousettus aegyptiacus)における抗血液凝固系殺鼠剤の薬物動態学/薬力学的解析
  武田 一貴; 真砂 皓大; 中山 翔太; 川合 佑典; 池中 良徳; 石塚 真由美, The Journal of Toxicological Sciences, 45, Suppl., S181, S182, Jun. 2020
  (一社)日本毒性学会, Japanese
• ヒゲ板中安定同位体比から推定するクロミンククジラ成熟雄の回遊生態
  石川啓史; 石塚真由美; 池中良徳; 中山翔太; 坂東武治; 田村力; 小西健志; 大槻真友子; 三谷曜子, 日本水産学会大会講演要旨集, 2020, 2020
• 添加剤含有プラスチック投与による海鳥への毒性影響の評価
  青木真奈実; 田中厚資; 池中良徳; 中山翔太; 綿貫豊; 高田秀重; 石塚真由美, 日本獣医学会学術集会講演要旨集, 163rd, 2020
• 行動毒性試験および二光子イメージングによるアセタミプリドの神経毒性評価
  平井杏梨; 杉尾翔太; 池中良徳; COLLINS Nimako; 中山翔太; 星信彦; 和氣弘明; 石塚真由美, 日本獣医学会学術集会講演要旨集, 163rd, 2020
• ペット動物から見る室内化学物質汚染の実態解明とリスク評価
  水川 葉月; 野見山 桂; 池中 良徳; 中山 翔太; 石塚 真由美; 高橋 真, 環境ホルモン学会研究発表会要旨集, 22回, 45, 45, Dec. 2019
  環境ホルモン学会(日本内分泌撹乱化学物質学会), Japanese
• 鉛散弾の経口投与によるバルバリーガモの鉛の血中濃度の経時変化および体内分布の解析
  佐藤裕; 石井千尋; 中山翔太; 一瀬貴大; 齊藤慶輔; 渡邊有希子; 小笠原浩平; 鳥本亮太; 小林篤史; 木村享史; 池中良徳; 石塚真由美, 日本獣医学会学術集会講演要旨集, 162nd, 504, 20 Aug. 2019
  Japanese
• 鳥類におけるUGT1E遺伝子の進化と食性の関わり
  川合佑典; 新屋惣; 中山翔太; 池中良徳; 石塚真由美; 久保田彰, 日本進化学会大会プログラム・講演要旨集(Web), 21st, 116 (WEB ONLY), 07 Aug. 2019
  Japanese
• LC-MS/MSを用いたイヌ尿中メタネフリンおよびノルメタネフリン測定
  井上 裕美子; 佐々木 東; 池中 良徳; 一瀬 貴大; 笹岡 一慶; 大菅 辰幸; 中山 翔太; 森下 啓太郎; 大田 寛; 石塚 真由美; 滝口 満喜, 日本獣医学会学術集会講演要旨集, 162回, 470, 470, Aug. 2019
  (公社)日本獣医学会, Japanese
• LC-MS/MS法を用いたイヌ血清中ステロイドホルモンの分析法の確立と内分泌疾患モデルを用いた実測
  白尾 大樹; 池中 良徳; 一瀬 貴大; 中山 翔太; 佐々木 東; 永田 矩之; 水川 葉月; 滝口 満喜; 石塚 真由美, 日本獣医学会学術集会講演要旨集, 162回, 470, 470, Aug. 2019
  (公社)日本獣医学会, Japanese
• 体内動態および行動毒性試験から見た動物用医薬品フィプロニルの影響評価
  鈴木 智裕; 池中 良徳; 中山 翔太; 水川 葉月; 一瀬 貴大; 佐々木 東; 笹岡 一慶; 石塚 真由美, 日本獣医学会学術集会講演要旨集, 162回, 501, 501, Aug. 2019
  (公社)日本獣医学会, Japanese
• 野生ラットを用いたDDT汚染状況の評価,毒性機序の解明
  本平航大; 池中良徳; 池中良徳; BEYENE Yared; 中山翔太; WEPENER Victor; SMIT Nico; VAN VUREN Johan; 江口哲史; SOUSA Ana Catarina; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.2A‐06, 11 Jun. 2019
  Japanese
• ザンビア共和国カブエ地域における資源採掘に起因した鉛汚染の実態解明と対策の検討:環境化学のその先へ
  中田北斗; 中山翔太; YABE John; MUZANDU Kaampwe; 豊巻治也; BEYENE Yared; KATABA Andrew; KATABA Andrew; ZYAMBO Golden; CHOONGO Kennedy; 池中良徳; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.1C‐18, 11 Jun. 2019
  Japanese
• PCBs曝露によるネコ肝トランスクリプトームへの影響
  水川葉月; NGYUEN Hoa Thanh; 岩田久人; 野見山桂; 池中良徳; 中山翔太; 横山望; 市居修; 滝口満喜; KHIDKHAN Kraisiri; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.1C‐08, 11 Jun. 2019
  Japanese
• 摂食プラスチックから海鳥への化学物質の移行の検証
  田中厚資; 綿貫豊; 高田秀重; 石塚真由美; 山下麗; 水川薫子; 水川葉月; 池中良徳; 中山翔太, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.P‐031, 11 Jun. 2019
  Japanese
• LC‐MS/MSを用いたイヌ血清中ステロイドホルモンの分析法の確立と副腎疾患モデルを用いた実測
  白尾大樹; 池中良徳; 一瀬貴大; 中山翔太; 佐々木東; 永田矩之; 水川葉月; 滝口満善; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.1A‐10, 11 Jun. 2019
  Japanese
• ネオニコチノイドの母子間移行の実態と移行メカニズムの解明
  池中良徳; 池中良徳; 一瀬貴大; NIMAKO Collins; 市川剛; 野見山桂; 長谷川浩; 中山翔太; 星信彦; 平久美子; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.2B‐05, 11 Jun. 2019
  Japanese
• デカブロモジフェニルエーテル(BDE209)の長期曝露がイエネコへ及ぼす影響
  田中啓介; 野見山桂; 水川葉月; 水川葉月; 高口倖暉; 田上瑠美; 横山望; 市居修; 滝口満喜; 笹岡一慶; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.1C‐09, 11 Jun. 2019
  Japanese
• 血漿中のステロイドホルモンの一斉分析法の開発とウマ性ホルモンの季節変動の解明
  一瀬貴大; 池中良徳; 池中良徳; 三津橋嵩史; 中山翔太; SAENGTIENCHAI Aksorn; 野見山桂; 田上瑠美; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 28th, ROMBUNNO.P‐106, 11 Jun. 2019
  Japanese
• ネオニコチノイド系殺虫剤と農薬の現状と今後の展望〜毒性学・農学・行政の視点から〜 ネオニコチノイド系殺虫剤の曝露実態の解明と毒性評価
  池中 良徳; 一瀬 貴大; Nimako Collins; 中山 翔太; 平野 哲史; 市川 剛; 加藤 恵介; 高橋 圭介; 長谷川 浩; 平 久美子; 有薗 幸司; 星 信彦; 藤岡 一俊; 石塚 真由美, The Journal of Toxicological Sciences, 44, Suppl., S53, S53, Jun. 2019
  (一社)日本毒性学会, Japanese
• Assessing the population-wide exposure to lead pollution in Kabwe, Zambia : blood lead level estimation based on survey data
  Hiwatari Masato; Yamada Daichi; Hangoma Peter; Narita Daiju; Mphuka Chrispin; Chitah Bona; Yabe John; Nakayama Shouta MM; Nakata Hokuto; Choongo Kennedy; Ishizuka Mayumi, Discussion Paper, Series A, 338, 1, 28, May 2019
  Faculty of Economics and Business, Hokkaido University, English
• ヒゲ板中安定同位体比変動から推定するクロミンククジラ雌の生活史履歴
  打田茉由果; 石塚真由美; 池中良徳; 水川葉月; 中山翔太; 坂東武治; 田村力; 小西健志; 鈴木一平; 三谷曜子, 日本水産学会大会講演要旨集, 2019, 162, 26 Mar. 2019
  Japanese
• 鉛汚染は末梢血中の免疫系細胞を変動させるのか?
  牛根奈々; 中山翔太; 石塚真由美; 羽山伸一, 日本野生動物医学会大会・講演要旨集, 25th, 2019
• PCR法によるオオワシ(Haliaeetus pelagicus)の孵化前雌雄判定
  中山翔太; 平野なぎ沙; 境秀文; 五島渉; 伊藤真輝; 池中良徳; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 25th, 2019
• In Vivo Pharmacokinetic/pharmacodynamic analysis of first-generation anticoagulant rodenticide warfarin with Egyptian fruit bats (Rousettus aegyptiacus) for risk assessment of Bonin fruit bats (Pteropus pselaphon)
  NAKAYAMA Shouta M.M.; MANAGO Kosuke; TAKEDA Kazuki; MORITA Ayuko; IKENAKA Yoshinori; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 28th, 2019
• DDTによる異物代謝酵素の遺伝子発現撹乱と健康影響評価
  本平航大; 池中良徳; 池中良徳; BEYENE Yared; 中山翔太; 江口哲史; 武田一貴; WEPENER Victor; SMIT Nico; VAN VUREN Johan; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 42nd, 2019
• 「基質結合部位からも活性残基からも離れたアミノ酸変異はどのように殺鼠剤抵抗性に寄与するのか?」ドッキングシミュレーション・分子動力学シミュレーションによるビタミンKエポキシド還元酵素の解析
  武田一貴; 池中良徳; 池中良徳; FOURCHES Denis; 田中和之; 中山翔太; 谷川力; TRIKI Dhoha; LI Xinhao; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 42nd, 2019
• 東京都小笠原諸島における殺鼠剤散布のアオウミガメへのリスク評価
  山村快哉; 武田一貴; 中山翔太; 川合佑典; 森田鮎子; 池中良徳; 小松謙之; 北山知代; 近藤理美; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 25th, 2019
• Characterization and differentiation of xenobiotic metabolism in mammalian animals through glucuronidation and sulfation profiling
  SAENGTIENCHAI Aksorn; IKENAKA Yoshinori; NAKAYAMA Shouta M.M.; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 28th, 2019
• Interactions of Neonicotinoid Insecticide with High Fat Diet Potentiate Signals of Type 2 Diabetogenesis in a Rodent Model.
  NIMAKO Collins; IKENAKA Yoshinori; IKENAKA Yoshinori; OKAMATSU-OGURA Yuko; KOBAYASHI Atsushi; NAKAYAMA Shouta M.M.; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 28th, 2019
• Exposure situation of neonicotinoids and its toxicity evaluation
  IKENAKA Yoshinori; TAIRA Kumiko; ARIZONO Kouji; HOSHI Nobuhiko; FUJIOKA Kazutoshi; ISHIZUKA Mayumi; ICHISE Takahiro; NIMAKO Collins; NAKAYAMA Shouta M.M.; HIRANO Tetsushi; ICHIKAWA Go; KATO Keisuke; TAKAHASHI Keisuke; HASEGAWA Hiroshi, Annual Meeting of the Japanese Society of Toxicology, 46, 0, S7, 2, 2019
  

  [in Japanese]

  , The Japanese Society of Toxicology, Japanese
• Concentration of neonicotinoid insecticides and their metabolites in Japanese bottled green-tea beverages and their safety evaluation
  Takamoto Akiko; Ishibashi Hiroshi; Ishizuka Mayumi; Arizono Koji; Ikenaka Yoshinori; Sugimoto Mayu; Iwano Manami; Fukushima Satoshi; Ichise Takahiro; Nakayama Shouta M. M.; Takahashi Keisuke; Kato Keisuke, Japanese Journal of Food Chemistry and Safety, 26, 1, 17, 27, 2019
  In this study, we determined the concentration of seven neonicotinoid insecticides and 13 of their metabolites in 46 bottled greenteabeverages, and estimated the daily intake of neonicotinoids in adults and children from these drinks. Liquid chromatographycoupled with electrospray ionization tandem mass spectrometry (LC–ESI/MS/MS) analysis revealed that six neonicotinoidsand two metabolites were detected in bottled green-tea beverages, and the 50th percentile concentration indicated dinotefuran > thiacloprid > clothianidin > imidacloprid > thiamethoxam > acetamiprid > N-desmethyl-acetamiprid > thiacloprid-amide. Theconcentration and composition profile of neonicotinoids in bottled green-tea beverages were different between brands; however,no significant differences were observed among manufacturing sites. The concentration of acetamiprid in bottled green-teabeverages was significantly correlated with that of N-desmethyl-acetamiprid. A significant relationship between concentrations ofthiamethoxam and clothianidin in bottled green-tea beverages was also observed, suggesting those neonicotinoids are metabolizedduring the tea leaves cultivation period. The daily intake for neonicotinoids in both adults and children from consumption ofbottled green-tea beverages was < 2.1% when compared with the acceptable daily intake (ADI) of neonicotinoids., Japanese Society of Food Chemistry, English
• 海鳥の越冬期の行動が繁殖地への汚染物質輸送に与える影響
  庄子晶子; ELLIOTT K; ARIS‐BROSOU S; 水川葉月; 中山翔太; 池中良徳; 石塚真由美; 桑江朝比呂; 渡辺謙太; 綿貫豊, 日本鳥学会大会講演要旨集, 2018, 97, 14 Sep. 2018
  Japanese
• XAFSを用いたザンビア鉛汚染地域の生物及び環境試料における鉛の化学形態の解明
  豊巻治也; 中山翔太; 中田北斗; 藤森崇; 塩田憲司; Yabe John; Muzandu Kaampwe; Beyene Yared; 池中良徳; 水川葉月; 石塚真由美, 第21回XAFS討論会, Sep. 2018
  Japanese, Summary national conference
• グルクロン酸転移酵素UGT1A6と哺乳類の食性の関係
  佐野花澄; 池中良徳; 近藤誉充; 川合佑典; 中山翔太; 水川葉月; 石塚真由美, 日本獣医学会学術集会講演要旨集, 161st, 469, 21 Aug. 2018
  Japanese
• オジロワシを中心とした鳥類の食性による腸内細菌叢変動と影響の解析
  山田尚輝; 中山翔太; 水川葉月; 小笠原浩平; 渡邊有希子; 齊藤慶輔; 伊藤真輝; 大澤夏生; 竹中康進; 小松謙之; 千葉茜; 内田義崇; 池中良徳; 石塚真由美, 日本獣医学会学術集会講演要旨集, 161st, 469, 21 Aug. 2018
  Japanese
• 誘導体化液体クロマトグラフィー質量分析法(LC/MS法)によるステロイドホルモン多成分一斉分析メソッドの開発及びその応用
  三津橋嵩史; 池中良徳; 池中良徳; 中山翔太; 水川葉月; 一瀬貴大; SAENGTIENCHAI Aksorn; 河合正人; 南保泰雄; 石塚真由美, 日本獣医学会学術集会講演要旨集, 161st, 467, 21 Aug. 2018
  Japanese
• What Makes Super Rats "Super"? ~Investigation of Mechanisms of Rodenticide Resistance~
  TAKEDA Kazuki; IKENAKA Yoshinori; TANAKA Kazuyuki D; NAKAYAMA Shouta M.M; TANIKAWA Tsutomu; MIZUKAWA Hazuki; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 45, 0, P, 71, 10 Aug. 2018
  <p>[in Japanese] </p>, The Japanese Society of Toxicology, Japanese
• Lead (Pb) pollution in Kabwe Mining area, Zambia: 10 years research achievements and future perspectives
  NAKAYAMA Shouta MM; ZYAMBO Golden; KURITANI Takeshi; NAKAGAWA Mitsuhiro; MIZUKAWA Hazuki; ISHIZUKA Mayumi; YABE John; IKENAKA Yoshinori; MUZANDU Kaampwe; CHOONGO Kennedy; NAKATA Hokuto; TOYOMAKI Haruya; BEYENE Yared; KATABA Andrew, Annual Meeting of the Japanese Society of Toxicology, 45, 0, P, 35, 10 Aug. 2018
  <p>[in Japanese] </p>, The Japanese Society of Toxicology
• Genetic and enzymatic features of phase II xenobiotic metabolism enzymes in carnivora species
  KONDO Takamitsu; IKENAKA Yoshinori; NAKAYAMA Shouta M. M; MIZUKAWA Hazuki; MITANI Yoko; NOMIYAMA Kei; TANABE Shinsuke; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 45, 0, P, 60, 10 Aug. 2018
  <p>[in Japanese] </p>, The Japanese Society of Toxicology
• 殺鼠剤に弱い野生動物種を探る:標的分子ビタミンKエポキシド還元酵素(VKOR)の鳥類における特徴および種差
  中山翔太; 森田鮎子; 池中良徳; 石井千尋; 水川葉月; 武田一貴; 川合佑典; 齊藤慶輔; 渡邊有希子; 大澤夏生; 伊藤真輝; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 24th, 150, Aug. 2018
  Japanese
• 鰭脚類を中心とした食肉目の薬物代謝酵素である硫酸転移酵素の種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 24th, 151, Aug. 2018
  Japanese
• 国内に生息する野生鳥類における鉛曝露状況の解明
  石井千尋; 池中良徳; 池中良徳; 中山翔太; 齊藤慶輔; 渡辺有希子; 小笠原浩平; 水川葉月; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 24th, 114, Aug. 2018
  Japanese
• PCR法による鳥類の雌雄判定:孵化前雌雄判定の試みとその課題
  中山翔太; 池中良徳; 石井千尋; 水川葉月; 川合佑典; 平野なぎ沙; 齊藤慶輔; 渡邊有希子; 大澤夏生; 伊藤真輝; 中村亮平; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 24th, 138, Aug. 2018
  Japanese
• シスプラチン膀胱内ソノポレーションの前臨床試験的検討
  佐々木東; 中山翔太; 大田寛; 大菅辰幸; 森下啓太郎; 水川葉月; 池中良徳; 石塚真由美; 滝口満喜, 日本獣医学会学術集会講演要旨集, 161回, 429, 429, Aug. 2018
  (公社)日本獣医学会, Japanese
• ザンビア共和国カブウェ鉱床地域における鉛汚染問題:10年間の研究結果と今後の課題
  中山翔太; YABE John; 池中良徳; MUZANDU Kaampwe; CHOONGO Kennedy; 中田北斗; 豊巻治也; BEYENE Yared; KATABA Andrew; ZYAMBO Golden; 栗谷豪; 中川光弘; 水川葉月; 石塚真由美, Journal of Toxicological Sciences, 43, Supplement, S226, Jun. 2018
  Japanese
• 食肉目動物での第II相抱合酵素の遺伝的性状および酵素学的性状の解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 野見山桂; 田辺信介; 石塚真由美, Journal of Toxicological Sciences, 43, Supplement, S238, Jun. 2018
  Japanese
• スーパーラットは何が「スーパー」なのか?~東京の殺鼠剤抵抗性クマネズミにおける抵抗性獲得機序の探索~
  武田一貴; 池中良徳; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, Journal of Toxicological Sciences, 43, Supplement, S244, Jun. 2018
  Japanese
• 誘導体化LC/MS/MS法による血漿中のステロイドホルモンおよびその抱合体代謝物35種類の一斉分析法の開発とその応用
  一瀬貴大; 池中良徳; 池中良徳; SAENGTIENCHAI Aksorn; 中山翔太; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.P‐086, 11 May 2018
  Japanese
• マラリアベクターコントロールにおけるDDTの使用実態とリスク評価
  池中良徳; THOMPSON Lesa; DARWISH Wageh; YOHANNES Yared; VAN VUREN Johan; SMIT Nico; WEPENER Victor; 中山翔太; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2A‐04, 11 May 2018
  Japanese
• GPS装置を用いた鉛鉱床地域のイヌの行動のモニタリングと鉛曝露の関係性
  豊巻治也; YABE John; 中山翔太; YARED Beyene; MUZANDU Kaampwe; 水川葉月; 池中良徳; 中田北斗; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.3C‐06(PA‐54), 11 May 2018
  Japanese
• HPLC‐APCI‐MSを用いたビタミンKの網羅的検出とin vitroビタミンKエポキシド還元酵素活性の評価
  武田一貴; 池中良徳; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2B‐01(PA‐22), 11 May 2018
  Japanese
• 野生哺乳類における硫酸転移酵素の動物種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2A‐09(PA‐18), 11 May 2018
  Japanese
• タイ王国におけるペットネコ血清およびペットフード中有機ハロゲン化合物と類縁化合物の汚染実態
  島崎真琴; 野見山桂; 水川葉月; SAENGTIENCHAI Aksorn; NGAMCHIRTTAKUL Araya; PENCHAREE Disdanai; 星野光希; 山本恭央; 高口倖暉; 石塚真由美; 池中良徳; 中山翔太; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2A‐03(PA‐14), 11 May 2018
  Japanese
• ネオニコチノイド系殺虫剤のヒト健康影響評価問題点の整理と今後の研究課題
  池中良徳; 一瀬貴大; NIMAKO Collins; 市川剛; 水川葉月; 中山翔太; 有薗幸司; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.1C‐16, 11 May 2018
  Japanese
• 血清中メタボローム解析によるペットネコ(Felis catus)の有機ハロゲン化合物毒性影響評価
  野見山桂; 江口哲史; 西川博之; 水川葉月; 山本恭央; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 田辺信介, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2A‐11, 11 May 2018
  Japanese
• 鉛鉱床地域における野生トカゲ亜目の生体内金属類濃度に影響を与える環境要因の解析
  銅谷理緒; 中山翔太; 中田北斗; 豊巻治也; YABE John; MUZANDU Kaampwe; BEYENE Yared; KATABA Andrew; ZYAMBO Golden; 水川葉月; 池中良徳; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.3C‐05(PA‐53), 11 May 2018
  Japanese
• 非侵襲的に採取可能な乳幼児の糞便における鉛安定同位体比を用いた鉛暴露経路の推定
  中山翔太; 豊巻治也; YABE John; MUZANDU Kaampwe; 中田北斗; 栗谷豪; 中川光弘; 水川葉月; 池中良徳; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.3C‐08, 11 May 2018
  Japanese
• 有機ハロゲン化合物曝露によるネコの生化学マーカーの変化および甲状腺機能に及ぼす影響評価
  水川葉月; KHIDKHAN Kraisiri; 高口倖暉; 横山望; 市居修; 滝口満喜; 笹岡一慶; 池中良徳; 池中良徳; 中山翔太; TSEND‐AYUSH Sainnoxoi; 野見山桂; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.2A‐10, 11 May 2018
  Japanese
• ネコのin vivo BDE209長期曝露試験による体内動態の解明および甲状腺ホルモンへの影響評価
  田中啓介; 野見山桂; 水川葉月; 高口倖暉; 田上瑠美; 横山望; 市居修; 滝口満喜; 笹岡一慶; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 27th, ROMBUNNO.1A‐03(PA‐13), 11 May 2018
  Japanese
• クロミンククジラ未成熟雌のヒゲ板安定同位体比を用いた摂餌履歴推定
  打田茉由果; 鈴木一平; 石塚真由美; 池中良徳; 中山翔太; 水川葉月; 田村力; 坂東武治; 小西健志; 三谷曜子, 日本水産学会大会講演要旨集, 2018, 44, 26 Mar. 2018
  Japanese
• スーパーラットは何が「スーパー」?東京の殺鼠剤抵抗性ラットにおける抵抗性獲得機序の解析
  武田一貴; 池中良徳; 池中良徳; 田中和之; 中山翔太; 谷川力; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 41st, ROMBUNNO.3P‐0628 (WEB ONLY), 2018
  Japanese
• 化学汚染の毒性影響の検知
  石塚真由美; 池中良徳; 中山翔太, 日本環境化学会講演会予稿集, 60th, 8, 2018
  Japanese
• Effects of PCB-exposure on thyroid hormone homeostasis in dog (canis lupus familiaris) and cat (felis catus)
  TAKAGUCHI Kohki; NAKAYAMA Shouta; IKENAKA Yoshinori; ISHIZUKA Mayumi; IWATA Hisato; KUNISUE Tatsuya; TANABE Shinsuke; NOMIYAMA Kei; NISHIKAWA Hiroyuki; MIZUKAWA Hazuki; TANOUE Rumi; KUSAKI Momoko; YOKOYAMA Nozomu; ICHII Osamu; TAKIGUCHI Mitsuyoshi, Annual Meeting of the Japanese Society of Toxicology, 45, 0, P, 72, 2018
  

  [in Japanese]

  , The Japanese Society of Toxicology, Japanese
• 幼児および新生児におけるネオニコチノイド系殺虫剤の曝露実態
  池中良徳; 宮原裕一; 一瀬貴大; 中山翔太; 水川葉月; 市川剛; 遠山千春; 石塚真由美, 日本内分泌かく乱化学物質学会研究発表会要旨集, 20th, 44, Dec. 2017
  Japanese
• ポリ塩化ビフェニル(PCBs)がネコの甲状腺機能に及ぼす影響
  水川葉月; 高居名菜; 野見山桂; 高口倖暉; 横山望; 市居修; 滝口満喜; 池中良徳; 池中良徳; 中山翔太; 石塚真由美, 日本内分泌かく乱化学物質学会研究発表会要旨集, 20回, 78, 78, Dec. 2017
  環境ホルモン学会(日本内分泌撹乱化学物質学会), Japanese
• Chemical Hazard in Bird Species
  中山翔太; 水川葉月; 池中良徳; 石塚真由美, 日本野生動物医学会誌, 22, 4, 69, 72, Dec. 2017
  <p> Nowadays, chemical hazards in bird have been reported worldwide, and above all, anticoagulant rodenticides for vertebrate pest control has frequently led to the unintentional exposures of non-target animals, especially birds. Several bird species, such as raptors, are suggested to be sensitive to anticoagulant rodenticides, however, the mechanism for this sensitivity has not yet been revealed. In wild rats, two causes are supposed to be possible reasons to explain the mechanism of rodenticide resistance; mutation of vitamin K epoxide reductase (VKOR) gene and acceleration in cytochrome P450-dependent detoxification. In case of wild birds, we reported that some of raptors have very low CYP-dependent warfarin metabolic activity relative to other avian species. In addition, we also showed Ki (inhibitory constant) for VKOR activity after warfarin treatment was 17- to 40-fold lower in ostriches or rats than in chickens. These facts were the first to indicate high warfarin resistance of chickens, and species difference in rodenticide sensitivity among birds.</p>, 日本野生動物医学会, Japanese
• 高次栄養段階生物への化学物質の感受性の種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, Endocrine Disrupter News Letter, 20, 3, 4, Dec. 2017
  Japanese
• 鳥類医学の発展に向けた新規腎障害マーカーの探索
  石井千尋; 池中良徳; 川合佑典; 市居修; 中山翔太; 水川葉月; 石塚真由美, 日本鳥学会大会講演要旨集, 2017, 100, 15 Sep. 2017
  Japanese
• 海鳥を介した汚染物質輸送
  庄子晶子; ELLIOTT K; ARIS‐BROSOU S; 水川葉月; 中山翔太; 池中良徳; 石塚真由美; 桑江朝比呂; 渡辺謙太; 綿貫豊, 日本鳥学会大会講演要旨集, 2017, 70, 15 Sep. 2017
  Japanese
• 鳥類におけるグルクロン酸抱合能の種差の解明と化学物質感受性の推定
  新屋惣; 池中良徳; 中山翔太; 水川葉月; 伊藤真輝; 高江洲昇; 齊藤慶輔; 渡邉有希子; 石塚真由美, 日本鳥学会大会講演要旨集, 2017, 105, 15 Sep. 2017
  Japanese
• 東京由来殺鼠剤抵抗性ラットを用いた新規抵抗性獲得機序の解明:ペントースリン酸経路の亢進による殺鼠剤代謝能の活性化
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 日本獣医学会学術集会講演要旨集, 160th, 504, 30 Aug. 2017
  Japanese
• 超音波と膀胱内注入療法を組み合わせた膀胱癌治療法の開発
  佐々木東; 中山翔太; 森下啓太郎; 中村健介; 大田寛; 水川葉月; 池中良徳; 石塚真由美; 滝口満喜, 日本獣医学会学術集会講演要旨集, 160回, 461, 461, Aug. 2017
  (公社)日本獣医学会, Japanese
• 進化する超音波治療技術の最前線 1)ソノポレーションを用いた膀胱内注入療法の開発
  佐々木東; 工藤信樹; 中山翔太; 滝口満喜, 超音波Techno, 29, 4, 27, 30, Jul. 2017
  日本工業出版, Japanese
• ポリ塩化ビフェニル(PCBs)暴露によるネコ甲状腺機能への影響評価~甲状腺ホルモンの脱ヨード化と代謝能の解析~
  水川葉月; 高居名菜; 横山望; 市居修; 滝口満喜; 野見山桂; 高口倖暉; 西川博之; 池中良徳; 池中良徳; 中山翔太; SAINNOXOI Tsend‐ayush; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.2A‐01, 05 Jun. 2017
  Japanese
• PCBs曝露がイヌ・ネコの甲状腺ホルモン恒常性へ及ぼす影響
  高口倖暉; 野見山桂; 西川博之; 水川葉月; 田上瑠美; 芳之内結加; 横山望; 市居修; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 岩田久人; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.2A‐02, 05 Jun. 2017
  Japanese
• イエネコのin vivo長期曝露試験:デカブロモジフェニルエーテル(BDE209)は甲状腺機能亢進症を引き起こすのか?
  水川葉月; 野見山桂; 池中良徳; 池中良徳; 中山翔太; SAENGTIENCHAI Aksorn; SAINNOXOI Tsendayush; 横山望; 笹岡一慶; 市居修; KHIDKHAN Kraisiri; 高居名菜; 滝口満喜; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.2A‐03, 05 Jun. 2017
  Japanese
• 幼児における尿中ネオニコチノイド濃度とその曝露実態の解明
  池中良徳; 池中良徳; 宮原裕一; 一瀬貴大; 八木橋美緒; 中山翔太; 水川葉月; 遠山千春; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.3C‐03, 05 Jun. 2017
  Japanese
• 血清中メタボローム解析によるイエネコのPCBs毒性影響評価
  野見山桂; 西川博之; 水川葉月; 高口倖暉; SAINNOXOI Tsend‐ayush; 横山望; 市居修; 滝口満喜; 石塚真由美; 池中良徳; 中山翔太; 江口哲史; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.2A‐05, 05 Jun. 2017
  Japanese
• In situ肝灌流試験によるワルファリン抵抗性クマネズミでのワルファリン代謝能の解明
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.P‐218, 05 Jun. 2017
  Japanese
• ヒト生体試料を用いたネオニコチノイドおよびネオニコチノイド代謝物の分析方法
  一瀬貴大; 池中良徳; 池中良徳; 藤岡一俊; 平久美子; 中山翔太; 水川葉月; 八木橋美緒; 有薗幸司; 加藤恵介; 高橋圭介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.P‐093, 05 Jun. 2017
  Japanese
• イエネコのin vivo長期曝露試験:デカブロモジフェニルエーテル(BDE209)の生体内変化
  田中啓介; 野見山桂; 水川葉月; 高口倖暉; 田上瑠美; SAENGTIENCHAI Aksorn; SAINNOXOI Tsend‐ayush; 横山望; 市居修; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 26th, ROMBUNNO.2A‐04, 05 Jun. 2017
  Japanese
• Contamination status and accumulation characteristics of heavy metals and arsenic in five seabird species from the central Bering Sea
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M. M. Nakayama; Hazuki Mizukawa; Yared Beyene Yohannes; Yutaka Watanuki; Masaaki Fukuwaka; Mayumi Ishizuka, JOURNAL OF VETERINARY MEDICAL SCIENCE, 79, 4, 807, 814, Apr. 2017
  English
• クロミンククジラ妊娠雌のヒゲ板の安定同位体比を用いた摂餌履歴推定
  打田茉由果; 伊藤慶造; 石塚真由美; 池中良徳; 中山翔太; 水川葉月; 坂東武治; 田村力; 小西健志; 鈴木一平; 三谷曜子, 日本水産学会大会講演要旨集, 2017, 24, 26 Mar. 2017
  Japanese
• 8-2-5 Multidisciplinary field research in Kabwe, Zambia, towards better understanding of lead contamination of the city - A short report from a field survey（8-2 地球環境，2017年度仙台大会）
  好井 優衣; 内田 義崇; Kawawa Banda; 濱本 亨; Kabenuka Munthali; Mukuka Mwansa; Yabe John; 石塚 真由美; 中山 翔太, 日本土壌肥料学会講演要旨集, 63, 0, 168, 168, 2017
  一般社団法人 日本土壌肥料学会, Japanese
• Elucidation the exposure route of brominated phenols in the blood of terrestrial mammals and species difference of sensitivity
  MIZUKAWA Hazuki; NOMIYAMA Kei; TANABE Shinsuke; IKENAKA Yoshinori; NAKAYAMA Shouta M.M; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 44, 0, S4, 4, 2017
  臭素系難燃剤であるポリ臭素化ジフェニルエーテル（PBDEs）は、薬物代謝酵素の働きにより水酸化PBDEs（OH-PBDEs）に代謝され、酵素による抱合作用を受けた後、体外へ排泄される。近年、OH-PBDEsの曝露経路にはPBDEsの曝露とその水酸化代謝由来に加え、海藻やシアノバクテリアなどが生成する海洋天然生成物の取り込みが重要視されている。また、同じく海洋天然生成物であるメトキシPBDEs（MeO-PBDEs）を体内に取り込み、脱メチル化によりOH-PBDEsが生成することも報告されている。さらに、ブロモフェノール（BPhs）も難燃剤など工業用製剤として使用され、海洋天然起源の生成物としても報告されている。OH-PBDEsやBPhsは甲状腺ホルモンと類似の構造を持つことから、血中の甲状腺ホルモン輸送タンパクに競合的に結合し、甲状腺ホルモンの恒常性撹乱や脳神経系への悪影響を引き起こすことが懸念されている。<br>本研究では、ネコやイヌなど陸棲哺乳類の血中に残留するハロゲン化フェノール類を分析し、汚染実態や残留特性、リスクについて考察した。その結果、全ての陸棲哺乳類の血中から天然および人工起源の臭素化フェノール類が検出され、特にネコで高値であった。また、検出された異性体組成から生体内の臭素化フェノール類の大部分は、餌から取り込んだPBDEsや天然起源のMeO-PBDEsが体内で変化した代謝生成物であると推察された。とくに、海産物を主原料とするキャットフードでは高濃度のMeO-PBDEsやBPhsが検出され、主要な曝露源となっていることが判明した。ネコではグルクロン酸抱合酵素の欠損による水酸化代謝物の感受性は高いことが予想され、本種はハロゲン化フェノール類のハイリスクアニマルであることが推察される。元来陸棲の肉食種であるイエネコに魚類を原料とするペットフードを与えることで、ネコの健康悪影響を引き起こしている可能性も考えられ、更なるリスク評価が重要課題と考えられた。, The Japanese Society of Toxicology, Japanese
• Thyroid hormone effects of polychlorinated biphenyls (PCBs) in cats-Analysis of deiodination and metabolism-
  MIZUKAWA Hazuki; NAKAYAMA Shouta M.M.; SAINNOXOI Tsend-ayush; TANABE Shinsuke; ISHIZUKA Mayumi; TAKAI Nana; YOKOYAMA Nozomu; ICHII Osamu; TAKIGUCHI Mitsuyoshi; NOMIYAMA Kei; TAKAGUCHI Kohki; NISHIKAWA Hiroyuki; IKENAKA Yoshinori, Annual Meeting of the Japanese Society of Toxicology, 44, 0, P, 55, 2017
  有機ハロゲン化合物の一種であるポリ塩化ビフェニル（PCBs）は甲状腺ホルモン（THs）の恒常性かく乱が懸念されており、実際、ヒトやげっ歯類においてはPCBs暴露により血中THs濃度の低下が認められている。ヒトの身近な動物であるネコは餌などを介してPCBsに暴露していると懸念され、THs恒常性に何らかの悪影響をもたらすことが予想される。本研究では、ネコの甲状腺機能に対するPCBsの影響を解析するため、<i>in vivo</i>投与試験したネコを用いて甲状腺機能への影響を解析した。血中のTHs濃度（総T4、総T3、遊離T4、遊離T3、リバースT3）を解析した結果、対照群と暴露群の間に有意な差は見られなかった。また、THsの恒常性に関与する遺伝子（甲状腺ホルモン受容体αおよびβ、脱ヨード酵素type1）の肝臓中発現量やTHs代謝に関わる酵素であるグルクロン酸抱合酵素（UGT1A1）の活性を調べたところ、対照群と暴露群の間に有意な差は見られなかった。<br>本実験結果では、ネコにおいてPCBs短期暴露によるTHsへの影響が認められなかったが、日本のペットネコにおけるモニタリング調査では、血中のTHs濃度とPCBs濃度との間に負の相関が見られており、有機ハロゲン化合物によるTHsかく乱が懸念されている。また、本研究試料のメタボローム解析結果では酸化ストレスの発現、抗酸化物質、電子伝達物質の生産阻害などが示唆されており、PCBsや水酸化代謝物による内分泌撹乱作用が心配される。THsの恒常性は非常に複雑な機構のもと維持されていることが知られており、負のフィードバック機構に加え、THsの活性化や代謝、排泄の調整にも多くの遺伝子やトランスポーター、酵素など様々な要因が関わっていることから、ネコは長期的かつ慢性的に化学物質に暴露されることで、甲状腺機能などへの悪影響が現れると考えられ、内分泌撹乱作用の作用機序について解析を進めることが重要である。, The Japanese Society of Toxicology, Japanese
• Super rat (Rodenticide Resistant Rats) is super metabolizer of warfarin ~revealed by in situ, in vitro approach~
  TAKEDA Kazuki; IKENAKA Yoshinori; TANAKA Kazuyuki D; NAKAYAMA Shouta M.M; TANIKAWA Tsutomu; MIZUKAWA Hazuki; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 44, 0, P, 21, 2017
  ワルファリン(Wf)等の抗凝血作用を持つ物質は殺鼠剤として広く用いられてきた。しかし、これらに対し抵抗性を持つ個体群が殺鼠剤使用頻度の高い世界各地の都市部に出現している。現在抵抗性ラットに有効な防除策は乏しく、新規防除策提案のため抵抗性獲得機序の解明は急務である。<br> 抵抗性ラットでは、Wfの標的分子ビタミンKエポキシド還元酵素（VKOR）に遺伝子変異が生じ、VKORのWf感受性が低下していることが報告された(Rost 2004 Nature 427:537–41)。しかし各地の抵抗性群は異なる変異パターンを有し、VKOR変異以外の抵抗性獲得機序の存在も疑われる。著者らが東京の殺鼠剤抵抗性ラットでのWfの体内動態を解析した所、抵抗性群は高いWf排泄能を有しており、代謝が抵抗性に関与する事が示唆された。(Takeda et al. 2016 Pestic Biochem Physiol. 134:1-7)<br>目的・方法：Wfは肝臓で薬物代謝酵素シトクロムP450 (CYPs)により水酸化され代謝される。そこで、抵抗性ラット肝臓におけるWf代謝能解明を目的に下記の実験を実施した。東京由来Wf抵抗性野生クマネズミのクローズドコロニーを用い、<i>in situ</i> Wf肝灌流試験を行い、生体に近い条件での代謝能を評価した。またCYPが局在するミクロソーム画分を肝臓より抽出し、<i>in vitro</i>での酵素活性も測定した。ミクロソーム中CYPs発現量はウェスタンブロットにて定量した。<br>結果・考察：<i>In situ</i>肝灌流試験では今回定量した5種全てのWf水酸化体において抵抗性群が感受性群より5～10倍程度有意に高い値を示した。また、<i>in vitro </i>Wf代謝活性でも抵抗性群は感受性群より有意に高い酵素活性を示し、CYPs発現量も有意に高い傾向であった。しかし、その差はいずれも1.3倍程度と肝灌流よりも小さかった。この結果から抵抗性ラットはWfの高代謝能を有するが、その要因はCYPsではなく<i>in vitro</i>試験では観察できなかった電子伝達系等に存在することが示唆された。, The Japanese Society of Toxicology, Japanese
• Estimation of the exposure level of neonicotinoid pesticide for infant
  IKENAKA Yoshinori; KATO Keisuke; TOHYAMA Chiharu; ISHIZUKA Mayumi; MIYABARA Yuichi; ICHISE Takahiro; YAGIHASHI Mio; NAKAYAMA Shouta; MIZUKAWA Hazuki; TAIRA Kumiko; ARIZONO Koji; TAKAHASHI Keisuke, Annual Meeting of the Japanese Society of Toxicology, 44, 0, O, 20, 2017
  ネオニコチノイド系殺虫剤は、哺乳類における体内蓄積性は短く、昆虫とヒトのニコチン受容体に対する親和性の違いから、ヒトに対する毒性は相対的に低いため、一定の基準以下であれば、日常生活においてその毒性は無視できると考えられている。しかし、日本では諸外国と比べ数倍～数十倍と果物や野菜、茶葉における食品残留基準値が高く設定されていること、また、記憶・学習などの脳機能に及ぼす影響をはじめ、発達神経毒性には不明な点が多いことなどから、健康に及ぼす懸念が払拭できていない。とりわけ、感受性が高いこどもたちや化学物質に過敏な人々の健康へのリスクを評価するためには、ネオニコチノイドが体内にどの程度取り込まれているかを把握することがまず必要である。そこで本調査では、長野県上田市の松くい虫防除が行われている地域の住民のうち、感受性が高いと考えられる小児（3歳～6歳）から尿を採取し、尿中のネオニコチノイドおよびその代謝物を測定することで、曝露評価を行う事を目的とした。当該調査では、松枯れ防止事業に用いる薬剤（エコワン３フロワブル、主要成分：Thiacloprid）の散布時期の前後に、46人の幼児から提供された尿試料中のネオニコチノイドとその代謝産物を測定した。また、同時に大気サンプルもエアーサンプラーを用いて採取し、分析に供した。分析した結果、Thiaclopridは検出頻度が30％程度であり、濃度は<LOD ～ 0.13 µg/Lであった。この頻度と濃度は、Dinotefuran（頻度、48～56％；濃度、<LOD ～ 72 µg/L）やN-dm-Acetamiprid（頻度、83～94%；濃度<LOD～18.7 µg/L)など今回検出された他のネオニコチノイドに比べて低い値であった。次に、尿中濃度からThiaclopridの曝露量を推定した結果、幼児一人当たり最大で1720 ng/日（平均160 ng/日）と計算された。また、分析対象とした全ネオニコチノイドの曝露量は最大640 µg/日であり、中でもDinotefuranの曝露量は最大450 µg/dayに達した。一方、これらの曝露量はADIに比べThiaclopridで1％未満(ADI；180 µg/日)、Dinotefuranで10％程度(ADI；3300 µg/日)であった。, The Japanese Society of Toxicology, Japanese
• Studies on polycyclic aromatic hydrocarbons formation in heat-treated meat
  DARWISH Wageh Sobhy; IKENAKA Yoshinori; NAKAYAMA Shouta M.M; MIZUKAWA Hazuki; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 44, 0, O, 15, 2017
  Polycyclic aromatic hydrocarbons (PAHs) are wide spread as environmental pollutants, which can be generated during the preparation of food. Food is the main source of exposure to PAHs for people who do not smoke. Epidemiological studies indicate that diets rich in fruits and vegetables can be associated with lower risks of numerous diseases and cancers. However, the exact mechanisms behind these effects are still unclear. The objectives of this study were firstly to estimate PAHs contents in some heat-treated meat samples collected from different localities in Egypt. Secondly, to investigate the mutagenic activities for some of the formed PAHs. Finally, to investigate the protective effects and mechanism of action of some micronutrients against the adverse effects of PAHs. <br> Polycyclic aromatic hydrocarbons were measured in heat-treated meat collected from different localities in Egypt using HPLC. Mutagenic activities of some formed PAHs were examined using Ames Salmonella typhimurium mutagenicity assay. Human HepG2 cells were exposed to environmental-relevant concentrations of some formed PAHs. Modulation of xenobiotic metabolizing enzymes (XMEs) mRNA expressions was investigated using real-time qPCR.<br> The results of this study indicated the formation of different PAHs in heat-treated meat with variable concentrations. Some of the formed PAHs had clear mutagenic activities such as benzo[a]pyrene. Obtained results declare the protective effects of carotenoids like β-carotene and retinoids like retinol against B[a]P induced adverse effects. Modulation of XMEs is proposed to be a possible mechanism for this protection. In conclusion, consumption of β-carotene and retinol in the areas of high PAH pollution is recommended., The Japanese Society of Toxicology, Japanese
• 全国規模での鳥類への鉛曝露:曝露指標として骨の利用の可能性
  石井千尋; 中山翔太; 池中良徳; ANDREW Kataba; 齊藤慶輔; 渡辺有希子; 槇納好岐; 松川岳久; 久保田章乃; 横山和仁; 水川葉月; 平田岳史; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 23rd, 81, 2017
  Japanese
• エストロジェン類高感度分析法の開発と野生動物におけるスクリーニング
  新屋惣; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 伊藤真輝; 高江洲昇; 大澤夏生; 綿貫豊; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 23rd, 125, 2017
  Japanese
• 薬物代謝酵素の動物種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, 日本薬学会年会要旨集(CD-ROM), 137th, ROMBUNNO.S45‐4, 2017
  Japanese
• 東京のワルファリン抵抗性ラットの抵抗性獲得機序の解明:ペントースリン酸経路の亢進を通したワルファリン代謝の活性化
  武田一貴; 池中良徳; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 日本生化学会大会(Web), 90th, ROMBUNNO.3AT12‐14(3P‐0236) (WEB ONLY), 2017
  Japanese
• Analysis of lead in wild birds to identify the cause of lead-poisoning
  石井千尋; 中山翔太; 水川葉月; 池中良徳; 石塚真由美, 中毒研究, 30, 4, 363, 367, 2017
  日本中毒学会 ; 2009-, Japanese
• 野生げっ歯類の殺鼠剤の抵抗性メカニズムと非対象動物に対する毒性メカニズム
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, 日本哺乳類学会大会プログラム・講演要旨集, 2016, 56, 23 Sep. 2016
  Japanese
• 野生動物の化学物質蓄積や感受性の種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, 日本獣医学会学術集会講演要旨集, 159th, 293, 30 Aug. 2016
  Japanese
• 野生動物及び実験動物におけるグルクロン酸抱合酵素の動物種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; SAENGTIENCHAI Aksorn; BEYENE Yared; 坂本健太郎; 和田昭彦; 服部薫; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美, 日本獣医学会学術集会講演要旨集, 159th, 493, 30 Aug. 2016
  Japanese
• 家畜・家禽の鉛安定同位体生体内分別の種差および歩哨動物としての有用性評価
  栂尾正雄; 中山翔太; YABE John; 池中良徳; 中田北斗; 石井千尋; 水川葉月; BEYENE Yared; SAENGTIENCHAI Aksorn; 石塚真由美, 日本獣医学会学術集会講演要旨集, 159th, 494, 30 Aug. 2016
  Japanese
• ヒト尿中のネオニコチノイドおよびその代謝産物の分析法の確立とヒトへの曝露評価
  池中良徳; 池中良徳; 藤岡一俊; 平久美子; 中山翔太; 水川葉月; 一瀬貴大; MARFO Jemima Tiwaa; 有薗幸司; 加藤恵介; 石坂真澄; 馬場浩司; 川上智規; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 25th, ROMBUNNO.1A‐07, 06 Jun. 2016
  Japanese
• メタボローム解析を用いたイエネコにおけるPCBsの毒性影響評価
  西川博之; 野見山桂; 水川葉月; 横山望; 市居修; 滝口満喜; 石塚真由美; 池中良徳; 中山翔太; 江口哲史; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 25th, ROMBUNNO.1A‐12, 06 Jun. 2016
  Japanese
• 有機ハロゲン化合物によるコンパニオンアニマルの汚染実態と甲状腺ホルモンへの影響評価
  野見山桂; 山本恭央; 水川葉月; 江口哲史; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介, 環境化学討論会要旨集(CD-ROM), 25th, ROMBUNNO.1A‐14, 06 Jun. 2016
  Japanese
• ネコにおけるポリ塩化ビフェニル(PCBs)の異物代謝機構解明と甲状腺ホルモンへの影響評価
  水川葉月; 前原美咲; 横山望; 市居修; 滝口満喜; 野見山桂; 西川博之; 池中良徳; 中山翔太; 高口倖暉; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 25th, ROMBUNNO.1A‐13, 06 Jun. 2016
  Japanese
• 脂肪組織における芳香族炭化水素受容体(AhR)の機能解明
  本平航大; 池中良徳; DARWICH Wageh S; 中山翔太; 水川葉月; 石塚真由美, Journal of Toxicological Sciences, 41, Supplement, S255, 84, Jun. 2016
  【はじめに】AhR(芳香族炭化水素受容体)はシトクロムP450をはじめとした種々の薬物代謝酵素を誘導することで異物の代謝に関与する受容体として研究が進められてきた。近年、従来主要な役割であると考えられてきた異物の代謝に加え、成長因子、抗酸化因子、炎症物質などを誘導するといった新たな生体内での役割が注目を集めている。AhRは肝臓や肺といった異物代謝活性が高い組織で活性が高く、上記に挙げた新たなAhRの働きの研究がなされているのに対し、薬物の「蓄積」という特徴的な応答を示す脂肪組織における反応は未知の部分が多い。そこで本研究では脂肪組織におけるAhRの働きを探求するとともに他組織との比較を試みた。<br>【方法】脂肪組織としてヒト脂肪由来幹細胞、肝臓組織としてヒト肝癌由来細胞を用い、AhRのリガンドと考えられているβ-naphthoflavoneを含む複数の化学物質を暴露した。これらの暴露細胞から抽出、精製したcDNAを用いて比較リアルタイムPCR法により各組織における異物代謝酵素と成長因子をはじめとした異物代謝とは直積関与するわけではない遺伝子の発現量を暴露-被暴露間、肝-脂肪細胞間で比較した。<br>【結果と考察】AhRリガンド暴露の結果、ヒト脂肪由来幹細胞、ヒト肝癌細胞の何れの細胞においてもCYP1A1や成長因子である繊維芽細胞増殖因子(fgf2など)の発現量の増加が確認された。種々の遺伝子で脂肪由来幹細胞と肝癌細胞の間で反応性や遺伝子発現量に違いが確認された。この結果から一般的に肝臓で誘導が認められている遺伝子に関して、脂肪組織でも誘導されていることが明らかになった。また今回観察を行った繊維芽細胞増殖因子では複数のサブファミリーがAhRリガンドにより誘導されており、繊維芽細胞増殖因子の全てのサブファミリーがAhRの支配を受けていることが示唆された。本研究の結果、種々の遺伝子で脂肪由来幹細胞-肝癌細胞間に反応性や遺伝子発現量に差が見られ、これが脂肪組織におけるAhRの他組織における働きとの違いと推測出来た。, 日本毒性学会, Japanese
• 東京由来ワルファリン抵抗性クマネズミクローズドコロニーでのワルファリン体内動態の解明
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美, Journal of Toxicological Sciences, 41, Supplement, S257, 89, Jun. 2016
  ワルファリンは抗凝血作用を示す化学物質であり、その薬効はビタミンK依存性血液凝固因子合成に不可欠なビタミンKエポキシド還元酵素 (VKOR)の阻害により発揮される。ワルファリンを含む種々の抗凝血薬は殺鼠剤として広く用いられているが、世界中の都市部でワルファリンに対し抵抗性を持つ野生齧歯類の棲息が確認されており、東京では棲息数の80%を占める地域すら存在する。これら野生齧歯類は重篤な人獣共通感染症を媒介するため、抵抗性獲得機序の解明は急務であるといえる。抵抗性の原因としてワルファリンの標的分子：VKORに遺伝子変異が生じ、それに伴いVKORのワルファリン感受性が低下する事が報告されている。しかしVKOR変異が生体レベルでどの程度抵抗性へ寄与するか不明な点も多くVKOR以外の抵抗性獲得機序が疑われている。そこでVKOR変異以外の要因を探索するため、筆者らは東京由来ワルファリン抵抗性野生クマネズミクローズドコロニーを確立し、その個体群を用いワルファリン経口投与後体内薬物動態解析を行った。その結果、抵抗性群ではワルファリン投与後のAUC(血漿中濃度－時間曲線下面積)、肝臓腎臓中蓄積濃度が感受性群に比べ有意に低く、一方で消失速度を示すクリアランスは有意に高かった。またワルファリンの代謝産物である水酸化ワルファリンの血漿中濃度は、抵抗性群において投与後1時間と非常に迅速に最高濃度に達し（感受性群では投与後6時間前後）、尿中への排泄量も水酸化体の一分子種(4’水酸化体)で有意に増加していた。このワルファリン代謝を担っているシトクロムP450分子種の肝ミクロソーム中タンパク発現量は抵抗性群では有意に高かった。<br>これらの結果は東京のワルファリン抵抗性個体群ではワルファリンの代謝・排泄能が亢進している事を示唆し、それによる迅速な解毒が抵抗性に寄与しているものと考えられる。, 日本毒性学会, Japanese
• UGTの動物種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, Journal of Toxicological Sciences, 41, Supplement, S106, 4, Jun. 2016
  外来性化学物質代謝の第II相反応では、第I相反応の代謝物の極性をさらに増加させるグルクロン酸抱合（UGT）や硫酸抱合（SULT）、グルタチオン抱合酵素などの抱合反応が主要な代謝となっている。化学物質の代謝能力は、生物の化学物質に対する感受性を決定する重要なファクターである。我々はこれまでの研究から、魚類から哺乳類まで、P450および第II相反応の抱合に大きな動物種差があることを報告してきた。<br>哺乳類ではUGT1ファミリーは、主に内因性物質を代謝するビリルビングループ(1A1-1A5)と外因性物質を代謝するフェノールグループ(UGT1A6-1A10)に大別される。我々は、食肉目を中心とした哺乳類におけるUGT1ファミリーの遺伝子解析を行ったところ、鰭脚類は外因性物質であるアセトアミノフェン及び1－ヒドロキシピレンに対するUGT活性がネコと同程度に低く、中でもトドおよびキタオットセイではUGT1A6の偽遺伝子化が明らかになった。またUGT1ファミリーの系統解析及びシンテニー解析の結果、哺乳類のUGT1ファミリーは内因性物質代謝を担うUGT1A1相同遺伝子及び外因性物質代謝を担うUGT1A6相同遺伝子がそれぞれ遺伝子重複した後、動物種ごとに独自に遺伝子重複/欠損が起き、UGT1A2-1A5及びUGT1A7-1A10遺伝子が形成されたことが示唆された。一方、UGTと基質特異性が一部重複するSULTに関しては、これまで教科書的にブタで活性が欠損しているとされてきたが、ブタの肝臓ミクロソームのKm/Vmaxによる酵素効率の比較では他の動物種と大きな差はないことや、新たに硫酸抱合酵素が低活性である哺乳類を同定した<br>そこで、今回、動物が有する化学物質代謝の種差と毒性発現の違いを、UGTを中心に紹介したい。, 日本毒性学会, Japanese
• Strain differences in cytochrome P450 mRNA and protein expression, and enzymatic activity among Sprague Dawley, Wistar, Brown Norway and Dark Agouti rats
  Yoshihiro Nishiyama; Shouta M. M. Nakayama; Kensuke P. Watanabe; Yusuke K. Kawai; Marumi Ohno; Yoshinori Ikenaka; Mayumi Ishizuka, JOURNAL OF VETERINARY MEDICAL SCIENCE, 78, 4, 675, 680, Apr. 2016
  English
• Feather mercury concentration in streaked shearwaters wintering in separate areas of southeast Asia
  Yutaka Watanuki; Ai Yamashita; Mayumi Ishizuka; Yoshinori Ikenaka; Shouta M. M. Nakayama; Chihiro Ishii; Takashi Yamamoto; Motohiro Ito; Tomohiro Kuwae; Philip N. Trathan, MARINE ECOLOGY PROGRESS SERIES, 546, 263, 269, Mar. 2016
  English
• Is hedgehog high sensitive to xenobiotics? Low metabolism enzyme activities observed in African hedgehog (Atalerix albiventris)
  SAENGTIENCHAI Aksorn; IKENAKA Yoshinori; SAM Nesta Bortey; JERMNARK Usuma; MIZUKAWA Hazuki; NAKAYAMA Shouta M.M; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 43, 0, P, 237, 2016
  African hedgehog, <i>Atalerix albiventris</i>, is a spiny mammal which becomes famous exotic pet in many counties. In order to elucidate xenobiotic metabolisms ability of hedgehogs, pyrene, one of the typical polycyclic aromatic hydrocarbon were exposed. From in vivo exposure study, pyrene was biotransformed to glucuronide and sulfate conjugates such as pyrene-1-glucuronide, pyrene-1-sulfate, and pyrenediol-sulfate and excreted to urine. Pyrene-1-glucuronide was main metabolite and limited excretion of sulfate conjugates were observed. Based on the results of in vivo exposure study, in vitro enzymatic kinetic experiments were performed by using various substrate and compare to rat and pig. Enzyme efficiency of cytochrome P450 (CYP) mediated Ethoxyresorufin <i>O</i>-deethylase activity, and warfarin 4'-, 6-, and 8-hydroxylation activity in hedgehogs were lower than that of rats. Furthermore, UDP-glucuronosyltransferase activities in hedgehogs were also lower <i>Km</i> than that of rats. Interestingly, the enzymatic efficiency of sulfation in hedgehogs was significantly lower than that of rats, whereas hedgehogs had similar sulfation ability as in pigs. Sulfation of hedgehogs may be limit activity in xenobiotic metabolism., The Japanese Society of Toxicology, Japanese
• Constitutive Effects of Lead on Aryl Hydrocarbon Receptor Gene Battery and Protection by β-carotene and Ascorbic Acid in Human HepG2 Cells.
  Wageh S Darwish; Yoshinori Ikenaka; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka, Journal of food science, 81, 1, T275-81, T281, Jan. 2016, [International Magazine]
  Lead (Pb) is an environmental pollutant that can get entry into human body through contaminated foods, drinks, and inhaled air leading to severe biological consequences, and has been responsible for many deaths worldwide. The objectives of this study were 1st to investigate the modulatory effects of environmentally relevant concentrations of Pb on AhR gene battery, which is controlling xenobiotics metabolism. 2nd, trials to reduce Pb-induced adverse effects were done using some phytochemicals like β-carotene or ascorbic acid. Human hepatoma (HepG2) cell lines were exposed to a wide range of Pb concentrations varying from physiological to toxic levels (0 to 10 mg/L) for 24 h. High Pb concentrations (1 to 10 mg/L) significantly reduced phase I (CYP1A1 and 1A2) and phase II (UGT1A6 and NQO1) xenobiotic metabolizing enzyme mRNA expression in a mechanistic manner through the AhR regulation pathway. Additionally, these Pb concentrations induced oxidative stress in HepG2 cells in terms of production of reactive oxygen species (ROS) and induced heme oxygenase-1 mRNA expression in a concentration-dependent phenomenon. Coexposure of HepG2 cells to physiological concentrations of some micronutrients, like β-carotene (10 μM) or ascorbic acid (0.1 mM), along with Pb (1 mg/L) for 24 h significantly reduced the levels of ROS production and recovered AhR mRNA expression into the normal levels. Thus, consumption of foods rich in these micronutrients may help to reduce the adverse effects of lead in areas with high levels of pollution., Wiley-Blackwell, English
• 鳥類における新規腎障害マーカーの探索
  石井千尋; 池中良徳; 市居修; 中山翔太; 西村紳一郎; 大橋哲; 田中誠一; 齊藤慶輔; 渡邊有希子; 水川葉月; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 22nd, 123, 2016
  Japanese
• 鳥類におけるグルクロン酸抱合酵素による薬物代謝
  新屋惣; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 齊藤慶輔; 渡邊有希子; 伊藤真輝; 高江洲昇; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 22nd, 97, 2016
  Japanese
• 本当にソノポレーションか?
  佐々木東; 工藤信樹; 中山翔太; 滝口満喜, 日本超音波医学会光超音波画像研究会プログラム・抄録集, 2016, 2nd, 22‐24, 2016
  Japanese
• In situ肝灌流モデルによる殺鼠剤抵抗性野生クマネズミにおけるワルファリン代謝能の解明
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 39th, ROMBUNNO.3LBA‐070 (WEB ONLY), 2016
  Japanese
• In vivo analysis of metabolic capacities and effects on the thyroid hormone and in cats treated with polychlorinated biphenyls
  MIZUKAWA Hazuki; TAKAGUCHI Kohki; TANABE Shinsuke; ISHIZUKA Mayumi; MAEHARA Misaki; YOKOYAMA Nozomu; ICHII Osamu; TAKIGUCHI Mitsuyoshi; NOMIYAMA Kei; NISHIKAWA Hiroyuki; IKENAKA Yoshinori; NAKAYAMA Shouta M.M., Annual Meeting of the Japanese Society of Toxicology, 43, 0, P, 6, 2016
  ポリ塩化ビフェニル（PCBs）の水酸化代謝物であるOH-PCBsは、肝臓内で薬物代謝酵素より生成され、その後体外へ排泄される。しかしながら、一部の水酸化代謝物は甲状腺ホルモン（TH）と類似の構造をもつため、THの恒常性を撹乱することが危惧されている。これまでに、多様な陸棲哺乳類の血中OH-PCBsを分析したところ、種間でOH-PCBsの組成に差異が認められ、中でも、ネコのOH-PCBs残留パターンは他種と大きく異なることから、本種は特異な代謝機能を有することが示唆された。しかし、ネコの異物代謝能の研究は僅かであり、化学物質暴露による毒性影響も不明な点が多い。本研究では、ネコにおけるPCBs <i>in vivo</i>暴露試験を実施し、体内動態および代謝に関与する酵素活性や遺伝子を解析するとともに、化学物質の暴露評価に繋がる基盤的情報の収集を目的とした。<br>コーン油に溶解した12異性体のPCBsを腹腔内投与し、経時採血した血清中PCBsおよびOH-PCBs濃度について同条件で実施したイヌの<i>in vivo</i>試験と比較した結果、異性体の残留パターンや体内動態にイヌとネコで種差が観察された。とくにネコでは低塩素化体の残留が顕著であった。また、代謝酵素活性および遺伝子解析の結果、PCBs暴露によりEROD、MROD、PROD活性は上昇するものの、第2相抱合酵素（UGTやSULT）活性は変化せず、PCBs暴露による抱合酵素活性への影響もみられなかった。また、<i>CYP1A1</i>および<i>CYP1A2</i>遺伝子の発現量の上昇も認められた。<br> 本研究により、ネコのPCBs吸収・代謝・排泄能はイヌと異なることが示唆され、とくに低塩素化OH-PCBsの毒性リスクは高いことが予想された。低塩素化OH-PCBsは血中でTH輸送タンパクとの競合結合や、THの硫酸抱合排泄の阻害、TH起因性遺伝子の転写抑制などが報告されており、ネコの甲状腺機能障害が懸念される。, The Japanese Society of Toxicology, Japanese
• 非実験動物における化学物質代謝能の特徴と種差
  池中良徳; 池中良徳; 筧麻友; 水川葉月; 中山翔太; 石塚真由美, 日本薬学会年会要旨集(CD-ROM), 136th, ROMBUNNO.S66-3, 2016
  Japanese
• Uridine Diphosphate-Glucuronosyltransferase (UGT) Xenobiotic Metabolizing Activity and Genetic Evolution in Pinniped Species
  Mayu Kakehi; Yoshinori Ikenaka; Shouta M. M. Nakayama; Yusuke K. Kawai; Kensuke P. Watanabe; Hazuki Mizukawa; Kei Nomiyama; Shinsuke Tanabe; Mayumi Ishizuka, TOXICOLOGICAL SCIENCES, 147, 2, 360, 369, Oct. 2015
  English
• 抗血液凝固系殺鼠剤の標的分子であるビタミンKエポキシド還元酵素(VKOR)の鳥類における特徴及び種差
  森田鮎子; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 渡邉研右; 齊藤慶輔; 渡邊有希子; 伊藤真輝; 高江洲昇; 石塚真由美, 日本獣医学会学術集会講演要旨集, 158th, 433, 30 Aug. 2015
  Japanese
• Accumulation of Heavy Metals and Metalloid in Foodstuffs from Agricultural Soils around Tarkwa Area in Ghana, and Associated Human Health Risks.
  Nesta Bortey-Sam; Shouta M M Nakayama; Osei Akoto; Yoshinori Ikenaka; Julius N Fobil; Elvis Baidoo; Hazuki Mizukawa; Mayumi Ishizuka, International journal of environmental research and public health, 12, 8, 8811, 27, 28 Jul. 2015, [International Magazine]
  This study was carried out to assess the extent of heavy metals and metalloid accumulation from agricultural soils to foodstuffs (viz, M. esculenta (cassava) and Musa paradisiaca (plantain)) around thirteen neighboring communities within Tarkwa, Ghana; and to estimate the human health risk associated with consumption of these foodstuffs. Concentrations of As, Cd, Co, Cr, Cu, Ni, Pb, and Zn were measured with an inductively coupled plasma-mass spectrometer and mercury analysis was done using a mercury analyzer. From the results, 30% of cassava samples collected, contained higher concentrations of Pb when compared to Codex Alimentarius Commission standard values. Bioconcentration factor indicated that Ni had higher capacity of absorption into food crops from soil than the other heavy metals. For both children and adults, the target hazard quotient (THQ) of Pb in cassava in communities such as Techiman, Wangarakrom, Samahu, and Tebe (only children) were greater than 1, which is defined as an acceptable risk value. This indicated that residents could be exposed to significant health risks associated with cassava consumption., MDPI, English
• Mercury concentrations in primary feathers reflect pollutant exposure in discrete non-breeding grounds used by Short-tailed Shearwaters
  Yutaka Watanuki; Takashi Yamamoto; Ai Yamashita; Chihiro Ishii; Yoshinori Ikenaka; Shouta M. M. Nakayama; Mayumi Ishizuka; Yuya Suzuki; Yasuaki Niizuma; C. E. Meathrel; R. A. Phillips, JOURNAL OF ORNITHOLOGY, 156, 3, 847, 850, Jul. 2015
  English
• 鳥類で起こっているケミカルハザードとそのメカニズム
  中山翔太; 水川葉月; 池中良徳; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 21st, 22, 01 Jul. 2015
  Japanese
• 北海道沿岸にストランディングした鯨類の臓器における金属濃度の測定とその比較検討
  川田大紀; 松田純佳; 松石隆; 中山翔太; 石塚真由美; 浅川満彦; 能田淳, 日本野生動物医学会大会・講演要旨集, 21st, 76, 01 Jul. 2015
  Japanese
• 第II相抱合反応の種差:食肉目におけるグルクロン酸抱合酵素の進化と遺伝子構造
  池中良徳; 筧麻友; 中山翔太; 川合佑典; 渡邊研右; 水川葉月; 野見山桂; 田辺信介; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.3A‐06, 17 Jun. 2015
  Japanese
• 渡り性海鳥2種の越冬海域と羽の水銀濃度
  綿貫豊; 山下愛; 石塚真由美; 池中良徳; 中山翔太; 石井千尋; 山本誉士; 山本誉士; 伊藤元裕; 桑江朝比呂; 鈴木裕也; 新妻靖彰; MEATHREL C.E; TRATHAN P.N; PHILLIPS R.A, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.P‐146, 17 Jun. 2015
  Japanese
• タンチョウの水銀蓄積特性に関する検討
  寺岡宏樹; 岡本絵梨佳; 久道萌; 中山翔太; 池中良徳; 石塚真由美; 北澤多喜雄, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.P‐145, 17 Jun. 2015
  Japanese
• 野生齧歯類におけるワルファリン抵抗性獲得機序の解明
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.3A‐07, 17 Jun. 2015
  Japanese
• ウマにおけるシトクロムP450の特性評価:ジアゼパム代謝を担うCYP3Aの重要性
  水川葉月; 中山翔太; 池中良徳; 速水秋; DARWISH Wageh Sobhy; 渡邊研右; 川合佑典; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.P‐030, 17 Jun. 2015
  Japanese
• 猛禽類における鉛中毒問題と骨における鉛分布の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中田北斗; 森田鮎子; 齊藤慶輔; 渡邊有希子; 神和夫; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 24th, ROMBUNNO.3D‐05, 17 Jun. 2015
  Japanese
• Phase II酵素の欠損動物と非欠損動物―新たな動物種マッピング―
  池中良徳; SAENGTIENCHAI Aksorn; SAENGTIENCHAI Aksorn; 筧麻友; DARWISH Wageh Sobhy; DARWISH Wageh Sobhy; 水川葉月; 中山翔太; 石塚真由美, Journal of Toxicological Sciences, 40, Supplement, S68, 3, Jun. 2015
  化学物質に対する最も基本的な生体防御機構は異物代謝系である。一方、これら異物代謝系の動物種差が、各動物の化学物質に対する感受性に強く寄与することが知られている。各生物が持つ異物代謝系には大きな種差があることが報告されている。例えば、異物代謝・第II相抱合反応において、ネコではグルクロン酸抱合、イヌではアセチル抱合およびブタでは硫酸抱合遺伝子が欠損していることが獣医学領域の研究から明らかになっており、投薬時に注意を要する。しかし、これら異物代謝系の動物種差に関する知見は、一部の実験動物を除くとほとんどの生物種で十分に解明されていない。<br>我々の研究グループでは、野生動物を含む様々な動物の異物代謝・第II相抱合反応を解明するため、in vivo、in vitroレベルおよびゲノム情報を用いた評価法の構築を行った。その結果、グルクロン酸抱合活性が低いと言われているネコ科動物以外にも、フェレットやトド、北オットセイ等の野生動物でもその活性が低いことが明らかになってきた。一方、硫酸抱合活性が低いと言われてきたブタでは、その活性は代表的な実験動物であるラットと変化が無いことが明らかになった。, 日本毒性学会, Japanese
• 日本海北部に来遊するキタオットセイの安定同位体比と利用海域との関係
  山田綾子; 堀本高矩; 石塚真由美; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 宮下和士, 日本水産学会大会講演要旨集, 2015, 49, 27 Mar. 2015
  Japanese
• Incidence and public health risk assessment of toxic metal residues (cadmium and lead) in Egyptian cattle and sheep meats
  W. S. Darwish; W. S. Darwish; M. A. Hussein; K. I. El-Desoky; Y. Ikenaka; S. Nakayama; H. Mizukawa; M. Ishizuka, International Food Research Journal, 22, 4, 1719, 1726, 01 Jan. 2015
• Protective effects of carotenoids and retinoids on benzo[a]pyrene induced mutagenicity and oxidative stress
  DARWISH Wageh Sobhy; IKENAKA Yoshinori; NAKAYAMA Shouta; MIZUKAWA Hazuki; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 42, 0, O, 20, 2015
  Benzo[a]pyeren (B[a]P) is one of the polycyclic aromatic hydrocarbons which is formed due to smoking of foods, incomplete combustion of woods, vehicle exhausts and cigarettes smokes. B[a]P gets entry into human and animal bodies mainly through their diets. B[a]P is confirmed to be pro-mutagenic and pro-carcinogenic to animals and humans in many studies. <br>Carotenoids such asβ-carotene and its metabolites like retinol and retinoic acids have a confirmed antioxidant activities through their radical scavenging roles. <br>The aim of this study, was firstly to estimate the B[a]P levels in fresh and heat treated meats. Additionally, B[a]P induced mutagenicity was studied using Salmonella mutagenicity assay. Moreover, B[a]P induced oxidative stress was examined using human hepatoma cell line (HepG2) cells after exposure to the relevant concentrations of B[a]P formed in heat-treated foods. In addition, the protective effects of carotenoids and retinoids against these harmful effects were also examined. The mechanisms behind these effects were also investigated.<br>The obtained results confirmed that carotenoids and retinoids have clear protective effects against B[a]P induced mutagenicity and oxidative stress, probably through their ability of induction of phase II and III enzymes and interference with the induction of phase I enzymes., The Japanese Society of Toxicology, Japanese
• 外来化学物質の代謝の種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳, 日本毒性病理学会講演要旨集, 31st, (JA)44,(EN)116, 2015
  Japanese
• ニワトリにおけるDDTの汚染状況と臓器蓄積性の解析
  伊藤玄悟; 池内良徳; BEYENE Yared; 中山翔太; 水川葉月; VUREN Johannes; WEPENER Victor; SMIT Nico; WYNAND Vlok; 石塚真由美, 日本獣医学会学術集会講演要旨集, 157th, 533, 11 Aug. 2014
  Japanese
• アフリカのゴミ集積場における化学物質の汚染実態と生体への健康影響の評価:ナイロビのダンドラ地域における家畜の重金属汚染の例
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; YARED YB; YABE John; 今内覚; 石塚真由美, 日本獣医学会学術集会講演要旨集, 157th, 533, 11 Aug. 2014
  Japanese
• 日本における猛禽類の鉛中毒被害状況と中毒原因,鉛体内分布の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中谷北斗; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美, 日本獣医学会学術集会講演要旨集, 157th, 533, 11 Aug. 2014
  Japanese
• ケニアの大規模ゴミ集積場・ダンドラ地域における家畜の化学物質汚染の実態と住民の健康影響評価
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; YOHANNES Yared B; 今内覚; 石塚真由美, J Toxicol Sci, 39, Supplement, S336, 187, Jul. 2014
  ケニア共和国の首都ナイロビ市内の大規模ゴミ集積場・ダンドラ地域は、世界第二位の巨大・高密度スラム街であり、地域内の子供の半数はWHO基準（100 μg/kg）以上の血中Pb濃度であることが報告されているが、家畜の汚染や生体への曝露源に関する報告はない。本研究では、ダンドラおよび対照区として同国・ナクル地域に生息するヤギ、ヒツジ、ブタおよびウシの血中金属類（10元素）濃度およびPb安定同位体比をICP-MSにより、PCBsおよび有機塩素系農薬（OCPs）濃度をGC-MSとGC-ECDにより測定した。<br> その結果、全てのサンプルでCr, Mn, Ni, Cu, Zn, As, Mo, Agの高濃度蓄積は認められず、PCBsおよびOCPsは検出限界以下であった。Pb濃度はナクルに比べてダンドラで高い蓄積傾向を示し、ヤギおよびヒツジでは有意差が認められた。ブタの平均Pb濃度はダンドラ（2600 μg/kg, dry wt:dw）がナクル（73 μg/kg, dw）の約35倍の高値を示した。ダンドラのウシからは、ヘム合成に関与するアミノレブリン酸脱水酵素活性が低下するとされる値（100μg/kg）と同程度のPb濃度（91 μg/kg以上）が検出され、血液毒性等の中毒症状の蔓延が示唆された。Cd濃度の地域差および種差は認められなかったが、総じて高値（570±460 ng/kg, dw）を示し、ウシの摂食によるヒトのCd曝露が示唆された。Pb安定同位体比は地域および動物種により異なる傾向を示し、地域内に複数の曝露源があること、動物種により主要な曝露源が異なることが示唆された。<br> 本研究より、両地域に生息する家畜には高濃度のPb, Cdが蓄積し、特にPb汚染はダンドラで深刻なレベルであり、その曝露源が複数存在することが示唆された。家畜と生活環境を共にするヒトへの同様の汚染も強く示唆された。, 日本毒性学会, Japanese
• 日本に生息する猛禽類の鉛汚染状況と鉛安定同位体比を指標とした汚染源の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中田北斗; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美, J Toxicol Sci, 39, Supplement, S336, 188, Jul. 2014
  【はじめに】北海道では、猛禽類において鉛弾摂取による鉛中毒が問題となっている。現在は鉛弾の使用規制が設けられているものの、未だに被害個体が発見されている。また、本州など他地域でも鉛中毒個体が発見されているが、北海道を除く地域における汚染実態調査は極僅かであり、鉛弾使用規制も不十分である。そこで、本研究では北海道、本州、四国において死亡した猛禽類の鉛濃度と鉛安定同位体比を測定し、鉛汚染状況と汚染源の解明を試みた。<br>【方法】試料は、1993年から2014年に北海道、本州、四国で死亡したイヌワシ、トビ、オオワシ、オオタカ、フクロウ、オジロワシ、オオハヤブサ、クマタカ、サシバ、ハイタカ、ツミ、チョウゲンボウの計49個体の肝臓を採取し、誘導結合プラズマ質量分析計で鉛濃度と鉛安定同位体比（²⁰⁷Pb/²⁰⁶Pb、²⁰⁸Pb/²⁰⁶Pb）を分析した。<br>【結果と考察】本研究の結果、1999‐2014年に北海道で死亡した4羽のオオワシにおいて、鉛中毒が疑われる値（11.0-29.5 mg/kg、湿重量）が検出された。北海道では2004年に大型獣の狩猟における鉛弾使用が禁止されているが、2013、2014年に採取されたオオワシにおいても高濃度の鉛蓄積が検出され、このうち1羽からはレントゲン撮影と剖検で胃内に鉛弾の破片が認められた。また岩手県で死亡したイヌワシからも高濃度の鉛蓄積（2.0 mg/kg）が認められた。さらに鉛安定同位体比を分析した結果、高濃度の鉛蓄積個体の鉛安定同位体比の値が同程度であった。このうち1羽から鉛弾が検出されたことを考慮すると、これらの高濃度蓄積個体の汚染源は鉛ライフル弾であると考えられた。<br> 上記の結果から、猛禽類の鉛弾摂取による中毒が未だに問題となっていることが明らかとなった。従って、北海道以外の地域における調査、また日本全国における鉛弾流通の完全禁止など規制強化の検討が必要であると考えられた。, 日本毒性学会, Japanese
• 鰭脚類を中心とした食肉目において異物代謝を担うグルクロン酸抱合酵素の特徴
  筧麻友; 中山翔太; 水川葉月; 池中良徳; 渡邊研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美, J Toxicol Sci, 39, Supplement, S281, Jul. 2014
  Japanese
• 鰭脚類におけるグルクロン酸抱合酵素の解析
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邊研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美, J Toxicol Sci, 39, Supplement, S223, 9, Jul. 2014
  【目的】グルクロン酸抱合酵素(UGT)は、異物代謝の第Ⅱ相抱合反応を担い、各動物の化学物質感受性決定に関与することが報告されている。食肉目ネコ亜目(<i>Feliformia</i>)では環境化学物質や薬物等の代謝に関与するUGT1A6の偽遺伝子化が報告されており、この偽遺伝子化によりアセトアミノフェン等の薬物の毒性作用が強く表れることが知られている。一方、食肉目に属する鰭脚類(<i>Pennipedia</i>)では、PCB、DDTなどの残留性有機汚染物質の高濃度蓄積が報告されているが、感受性に関与するUGTについての研究がほとんど行われていない。そこで、鰭脚類を中心とした食肉目において、UGTの機能解析及び系統解析を行い、種差を明らかにすることを目的とした。<br>【方法】食肉目に属するネコ(<i>Felis catus</i>)、イヌ(<i>Canis familiaris</i>)、鰭脚類であるトド(<i>Eumetopias jubatus</i>)、キタオットセイ(<i>Callorhinus ursinus</i>)、カスピカイアザラシ(<i>Phoca caspica</i>)及び対照としてラット(<i>Rattus norvegicus</i>)の肝臓ミクロソームを調整した。この肝臓ミクロソームを用いて、1-ヒドロキシピレンを基質としてUGT活性を測定した。さらに食肉目UGT1A遺伝子について、他の哺乳類と比較し、系統解析を行った。<br>【結果及び考察】1-ヒドロキシピレンを基質として用いたところ、イヌはラットと同程度のUGT活性を示したが、鰭脚類3種およびネコのUGT活性はラットの3分の1以下だった。また、UGT1A遺伝子は一般に2-10程度のホモログが近接して染色体上に存在しているが、系統解析及びシンテニー解析より、食肉目は齧歯目に比べUGT1A領域が短くUGT1A分子種数が少ないことが確認された。さらに、トドおよびキタオットセイでは、UGT1A6のエクソン1領域に2塩基挿入によるストップコドンが生じ、偽遺伝子化していることが明らかになった。以上の結果より、鰭脚類は、UGTによる異物代謝能が低く、環境化学物質に対する感受性が高い可能性が考えられた。, 日本毒性学会, Japanese
• ネコ科動物における有機ハロゲン化合物の代謝能解析
  水川葉月; 池中良徳; 野見山桂; 田辺信介; 宇根有美; 伊藤真輝; 高江洲昇; 長野靖子; 中山翔太; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 23rd, ROMBUNNO.3B-14, 14 May 2014
  Japanese
• 日本に生息する猛禽類における鉛汚染状況の解析
  石井千尋; 池中良徳; 中山翔太; 水川葉月; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 23rd, ROMBUNNO.3D-03, 14 May 2014
  Japanese
• ベクターコントロールのための薬剤散布の生態系およびヒト健康に与える影響評価:アフリカにおけるDDT使用の現状と課題
  池中良徳; YOHANNES Yared Beyene; 中山翔太; 水川葉月; VAN VUREN Johannes J; WEPENER Victor; SMIT Nico J; WYNAND Vlok; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 23rd, ROMBUNNO.2A-08, 14 May 2014
  Japanese
• アフリカのゴミ集積場における化学物質の汚染実態と生体への健康影響の評価:ナイロビのダンドラ地域における重金属汚染の例
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; YOHANNES Yared B; 今内覚; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 23rd, ROMBUNNO.3D-01, 14 May 2014
  Japanese
• 鰭脚類においてグルクロン酸抱合酵素が担う異物代謝
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邉研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美, 日本野生動物医学会大会・講演要旨集, 20th, 75, 2014
  Japanese
• 食肉目におけるグルクロン酸抱合酵素の遺伝子解析
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邉研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美, 日本分子生物学会年会プログラム・要旨集(Web), 37th, 3P-0853 (WEB ONLY), 2014
  Japanese
• ハシボソミズナギドリの羽根の化学マーカーによる海洋環境モニタリング
  綿貫豊; 山下愛; 保科賢司; 鈴木優也; 山本誉士; 石塚真由美; 池中良徳; 中山翔太; 石井千尋; 新妻靖章; MEATHREL C; PHILLIPS R. A, 日本鳥学会大会講演要旨集, 2013, 53, 13 Sep. 2013
  Japanese
• In vitroにおけるウマのジアゼパム代謝
  速水秋; DARWISH Wageh; 池中良徳; 中山翔太; 石塚真由美, 日本獣医学会学術集会講演要旨集, 156th, 388, 30 Aug. 2013
  Japanese
• Molecular evaluation of a new highly sensitive aryl hydrocarbon receptor in ostriches
  N. Fujisawa; W. S. Darwish; Y. Ikenaka; E. Kim; J. Lee; H. Iwata; S. Nakayama; M. Ishizuka, POULTRY SCIENCE, 92, 7, 1921, 1929, Jul. 2013
  English
• 鳥類における金属の汚染状況と蓄積特性の解析
  石井千尋; 池中良徳; 中山翔太; 鈴木優也; 綿貫豊; 渡邊雄児; 福若雅章; YOHANNES Yared B; 川合佑典; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 22nd, ROMBUNNO.1-1B-1-1, Jul. 2013
  Japanese
• ガーナの金鉱山周辺(オブアシ自治区)におけるヒ素汚染と陸生哺乳類への毒性影響評価
  大谷豪; 池中良徳; 中山翔太; AKOTO Osei; APAU Joseph; BAIDOO Elvis; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 22nd, ROMBUNNO.1-1B-2-2, Jul. 2013
  Japanese
• 野生げっ歯類におけるワルファリン抵抗性機構
  池中良徳; 田中和之; 中山翔太; 春成常仁; 谷川力; 水川葉月; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 22nd, ROMBUNNO.3-2D-6-3, Jul. 2013
  Japanese
• オオミズナギドリの越冬海域と尾羽の水銀濃度
  綿貫豊; 山下愛; 石塚真由美; 池中良徳; 中山翔太; 石井千尋; 山本誉士; 伊藤元裕; 桑江朝比呂, 日本生態学会大会講演要旨集, 60th, 118, 05 Mar. 2013
  Japanese
• 海鳥における金属の汚染状況と蓄積特性の解析
  石井千尋; 池中良徳; 中山翔太; 鈴木優也; 綿貫豊; 渡邊雄児; 福若雅章; YARED Yohannes Beyene; 川合佑典; 石塚真由美, 日本獣医学会学術集会講演要旨集, 155th, 260, 04 Mar. 2013
  Japanese
• Pyrene metabolism and the role of phase I and phase II enzymes in freshwater turtles
  OROSZLANY Balazs; IKENAKA Yoshinori; SAENGTIENGCHAN Aksorn; OGURI Mami; NAKAYAMA Shouta; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 40, 0, 2013
  Introduction : Reptile populations all around the world are decreasing. The dominant stressors are decrease of habitats, targeted harvesting and climate change. Environmental pollution could be a common factor weakening populations, yet we know little about the effect of xenobiotics on reptiles. Pyrene, as a representative of polycyclic aromatic hydrocarbons (PAHs), was choosen to study the metabolism in freshwater turtles, as disasters involving PAHs (oil spills) are one of the main causes of health and reproductive problems in water-living organism. <br>Materials and Methods:Red-eared sliders (<i>Trachemys scripta elegans</i>), Chinese pond turtles (<i>Mauremys reevesii</i>) and Chinese softshell turtles (<i>Pelodiscus sinensis</i>) were used. Pyrene exposure occurred thorugh oral feeding (4 mg/kg pyrene, dissolved in corn oil) or through water (250 &mu;g/l). Exposed water was filtered, passed through a solid-phase cartridge, and eluded with methanol. Metabolites were determined by HPLC with FD equipped with an ODS column, and identified by an MS/MS system. Liver subcellular fractions were isolated from fresh samples, protein concentration were measured by BCA protein assay. EROD, UGT and SULT activity were measured.<br>Results and Discussion:Distinct metabolite distributions were measured for each species. The dominant metabolite in all three species was pyrene-1-sulfate. All enzyme activities were low compared to mammals (rat). Sulfate conjugation was the dominant phase II metabolic pathway in all three species., The Japanese Society of Toxicology, English
• Regulatory effects of carotenoids on Aryl hydrocarbon receptor (AhR) gene battery
  DARWISH Wageh Sobhy; IKENAKA Yoshinori; NAKAYAMA Shouta; ISHIZUKA Mayumi, Annual Meeting of the Japanese Society of Toxicology, 40, 0, 2013
  <b>[Introduction]</b> <br> In our previous work, positive correlations between CYP1A- dependent activities, protein expression and &beta;-carotene (BC) accumulation in the ungulates were observed, however these cross-talks were poorly understood. Additionally, the regulatory effects of carotenoids on xenobiotics metabolizing enzymes (XMEs) had received little attention. Thus, the aim of the current study is to deeply investigate the constitutive response of AhR gene battery to the exposure to BC under various doses in the human hepatoma cell line (HEPG2) cells. Moreover, the possible regulatory mechanisms of these cross-talks between AhR and BC will be declared.<br> <b>[Materials and Methods]</b> <br> HEPG2 cell lines were treated with different concentrations of BC (0-10 &micro;M) for 12-24h. The mRNA expression for phase I (CYP1A1 and 1A2), Phase II (UGT1A6 and NQO1) enzymes and AhR were examined using Real-Time PCR. Protein expression of AhR was investigated using western blotting. Rat H4IIE cells were transfected with h-XRE luciferase reporter plasmid and exposed to BC for 24h and dual- luciferase reporter assay was performed.<br> <b>[Results and Discussion]</b> <br> BC differentially modulated XMEs (Phase I and II enzymes) expression in dose-dependent fashion. In parallel, BC induced AhR mRNA, protein expression and luciferase activity. Thus, &beta;-carotene differentially modulated AhR gene battery., The Japanese Society of Toxicology, English
• Effects of lead, cadmium and other metals in domestic animals near a lead-zinc mine in Kabwe, Zambia
  YABE John; NAKAYAMA Shouta M.M; IKENAKA Yoshinori; MUZANDU Kaampwe; CHOONGO Kennedy; ISHIZUKA Mayumi; UMEMURA Takashi, 環境化学討論会要旨集(CD-ROM), 21st, ROMBUNNO.1B-12, 10 Jul. 2012
  English
• Levels and Bioaccumulation of Organochlorine Pesticides in Fish Species from Lake Ziway, ETHIOPIA
  YARED B. Yohannes; IKENAKA Yoshinori; WATANABE Kensuke; SAENGTIENCHAI Aksorn; NAKAYAMA Shouta; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 21st, ROMBUNNO.1B-06, 10 Jul. 2012
  English
• アカハライモリとアフリカツメガエルにおける異物代謝酵素の発現量の比較
  上田春樹; 中山翔太; 川合佑典; 田中(上野)寛子; 池中良徳; 石塚真由美, は虫両棲類学会報, 2012, 1, 89, 31 Mar. 2012
  Japanese
• ラットにおけるシトクロムP450の系統差
  西山義広; 池中良徳; 大野円実; 渡邊研右; 川合佑典; 中山翔太; 田中和之; 石塚真由美, 日本獣医学会学術集会講演要旨集, 152nd, 335, 31 Aug. 2011
  Japanese
• ラットの消化管における異物代謝酵素の比較
  糸谷悠美; 池中良徳; 大野円実; 中山翔太; SOBHY Wageh; 石塚真由美, 日本獣医学会学術集会講演要旨集, 152nd, 335, 31 Aug. 2011
  Japanese
• Effects of current malaria control in lake environment; The levels of Organochlorine pesticide and toxic metals in fish species from Lake Awassa, ETHIOPIA
  YARED Beyene; IKENAKA Yoshinori; WATANABE Kensuke; SAENGTIENCHAI Aksorn; NAKAYAMA Shouta; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 20th, ROMBUNNO.2E-01, 01 Jul. 2011
  English
• Metal and metalloid levels and bio-accumulation characteristics in soil, sediment, land plants and hippopotami (Hippopotamus amphibius L) from the South Luangwa National Park, Zambia
  NAKAYAMA Shouta M.M; IKENAKA Yoshinori; MUZANDU Kaampwe; CHOONGO Kennedy; M’KANDAWIRE Ethel; YASUDA Jun; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 20th, ROMBUNNO.P-215, 01 Jul. 2011
  English
• Uptake of lead, cadmium and other metals in the liver and kidneys of cattle near a lead-zinc mine in Kabwe, Zambia
  YABE John; NAKAYAMA Shouta M.M; IKENAKA Yoshinori; MUZANDU Kaampwe; ISHIZUKA Mayumi; UMEMURA Takashi, 環境化学討論会要旨集(CD-ROM), 20th, ROMBUNNO.3E-01, 01 Jul. 2011
  English
• Metal concentration and stable isotope ratio analysis (d13C and d15N) in water, sediment and fish from Lake Itezhi-tezhi, Zambia
  NAKAYAMA Shouta M.M; IKENAKA Yoshinori; MUZANDU Kaampwe; CHOONGO Kennedy; YABE John; MUROYA Taro; UMEMURA Takashi; ISHIZUKA Mayumi, 環境化学討論会要旨集(CD-ROM), 20th, ROMBUNNO.2E-09, 01 Jul. 2011
  English
• ガーナの金鉱山周辺(オブアシ自治区)における金属汚染と野生ラットにおける毒性影響評価
  大谷豪; 池中良徳; 中山翔太; AKOTO Osei; APAU Joseph; BAIDOO Elvis; 石塚真由美, 環境化学討論会要旨集(CD-ROM), 20th, ROMBUNNO.P-214, 01 Jul. 2011
  Japanese
• ラットの消化管における異物代謝酵素の発現パターン
  糸谷悠美; 池中良徳; 大野円実; 中山翔太; WAGEH Sobhy; 石塚真由美, 日本獣医学会学術集会講演要旨集, 151st, 271, 01 Mar. 2011
  Japanese
• Rattus属における薬物代謝能とシトクロムP450の種差・系統差
  西山義広; 田中和之; 大野円実; 渡邊研右; 川合佑典; 中山翔太; 谷川力; 春成常仁; 池中良徳; 石塚真由美, 日本獣医学会学術集会講演要旨集, 151st, 270, 01 Mar. 2011
  Japanese
• Heavy metal contamination of soil and sediment in Zambia
  Ikenaka Yoshinori; Nakayama Shouta M. M; Muzandu Kaampwe; Choongo Kennedy; Teraoka Hiroki; Mizuno Naoharu; Ishizuka Mayumi, African Journal of Environmental Science and Technology, 4, 11, 729, 739, Nov. 2010
  Heavy metal pollution is one of the most important problems in Zambia and causes serious effects to humans and animals. The aim of the present study was to evaluate the spatial distribution of heavy metals in main areas of Zambia and understand the characteristics of the pollution in each area. River and lake sediments and soil samples were collected from a large area of Zambia and analyzed for ten heavy metals (Cr, Co, Ni, Cu, Zn, As, Cd, Pb, Sr and Hg). The results indicate that heavy metal pollution in Zambia has strong regional differences. Using cluster analysis, the patterns of heavy metal pollution were divided into three major clusters: (1) Kabwe, (2) Copperbelt and (3) Lusaka and other areas. Heavy metals in the Copperbelt area are transported to downstream areas by the Kafue River. Pollution was also detected in national parks, and Lake Itezhi-tezhi has been polluted with high concentrations of Cu, possibly from mining activities in the upper reaches of the river. However, areas geographically distant from mining beds had only moderate or low heavy metal concentrations, although the concentrations of Pb and Zn were highly correlated with the populations of each town. Our findings indicate that heavy metal pollution in Zambia is still increasing, due to human activities, especially mining., Academic Journals, English
• アフリカ諸国における重金属汚染の現状と野生動物への影響
  池中良徳; 中山翔太; 石塚真由美, 北海道獣医師会雑誌, 54, 10, 569, 575, 10 Oct. 2010
  Japanese
• ザンビア共和国をモデルとした微量元素汚染:ウシにおける微量元素濃度とメタロチオネインおよびサイトカインmRNA発現量
  室谷太郎; 池中良徳; 中山翔太; YABE John; MUZANDU Kaampwe; CHOONGO Kennedy; 今内覚; 梅村孝司; 石塚真由美, 日本獣医学会学術集会講演要旨集, 150th, 323, 01 Sep. 2010
  Japanese
• 野生ネズミの微量金属汚染‐日本におけるバイオモニタリングとその生体影響
  OROSZLANY Balazs; 池中良徳; 谷川力; 春成常仁; 田中和之; 中山翔太; 石塚真由美, 日本獣医学会学術集会講演要旨集, 150th, 323, 01 Sep. 2010
  Japanese
• ザンビア共和国の鉱床活動による微量元素汚染の野生ラットへの影響
  濱田泰平; 池中良徳; 中山翔太; MUZANDU Kaampwe; CHOONGO Kennedy; 寺岡宏樹; 石塚真由美, 日本獣医学会学術集会講演要旨集, 150th, 323, 01 Sep. 2010
  Japanese
• Estimation of environmental toxic effects by using wild rats: a possible model for terrestrial heavy metal biomonitoring
  OROSZLANY Balazs; IKENAKA Yoshinori; TANIKAWA Tsutomu; HARUNARI Tsunehito; TANAKA Kazuyuki; NAKAYAMA Shouta; ISHIZUKA Mayumi, 環境化学討論会講演要旨集, 19th, 802, 803, 20 Jun. 2010
  English
• ザンビア共和国における土壌の重金属汚染
  中山翔太; 池中良徳; MUZANDU Kaampwe; CHOONGO Kennedy; 濱田恭平; 室谷太郎; 寺岡宏樹; 水野直治; 石塚真由美, 環境化学討論会講演要旨集, 19th, 314, 315, 20 Jun. 2010
  Japanese
• ザンビア共和国をモデルとした重金属類汚染:家畜における重金属類濃度とバイオマーカーmRNA発現量
  室谷太郎; 中山翔太; 池中良徳; YABE John; MUZANDU Kaampwe; CHOONGO Kennedy; 今内覚; 梅村孝司; 石塚真由美, 環境化学討論会講演要旨集, 19th, 816, 817, 20 Jun. 2010
  Japanese
• 多環芳香族炭化水素類(PAHs)に対する両棲類の異物代謝機構の解明:両棲類で観察された第II相抱合反応の特徴と種差
  上田春樹; 中山翔太; 池中良徳; 石塚真由美, J Toxicol Sci, 35, Supplement, S196, 320, May 2010
  【目的】2004年国際自然保護連合より，世界の両棲類種の約1/3が危機に晒されており，また，1980年代以降120種以上が絶滅した可能性があると発表された。その原因の一つに環境化学物質への曝露が考えられている。しかし，両棲類では化学物質の感受性を決定する異物代謝系でさえ十分に解明されていない。そこで，環境化学物質の一つとして多環芳香族炭化水素類（PAHs）に注目し，両棲類における代謝反応，特に第II相抱合反応を明らかにすることを試みた。<BR>【方法】PAHsのモデルとして，ピレン（4環のPAH）を用いた。両棲類はアカハライモリ（Cynops pyrrhogaster），アフリカツメガエル（Xenopus laevis）を用いた。さらに対照として，ピレンの代謝に対し知見が得られているメダカ（Oryzias latipes）に注目し，ピレンの曝露（24h，125ppb，24℃）を行った。固相抽出（PS@Liq; 昭和電工）を用いて排泄物を含む水中からピレン代謝物を精製し，HPLC/蛍光検出および質量分析によりその同定を行った。<BR>【結果と考察】ピレン代謝産物として，魚類のメダカではグルクロン酸抱合体（m/z 297）と硫酸抱合体（m/z 393）のみが検出され，前者が主産物であった。両棲類のアフリカツメガエルでは硫酸抱合体が主産物として検出され，グルクロン酸抱合体はほとんど検出されなかった。一方，同じ両棲類であるアカハライモリでは，硫酸抱合体，グルクロン酸抱合体がともに検出され，アフリカツメガエルとは異なるパターンを示した。さらに，本研究において，両棲類では，メダカでは検出されなかった代謝産物が数種類検出された。これらの未知の代謝産物をMSにより測定したところ，m/z 299，315，381など，既知の抱合体とは異なるm/zが観察された。本研究により，化学物質の解毒経路に重要な第II相抱合反応について，両棲類では魚類とは異なる代謝抱合能を示すこと，有尾類と無尾類で異なる代謝パターンを示す可能性が示唆された。, 日本毒性学会, Japanese
• ザンビア共和国における重金属汚染:野生ラットをモデルとした陸圏の汚染モニタリング
  濱田恭平; 中山翔太; 池中良徳; KAAMPWE Muzandu; KENNEDY Choongo; 水野直治; 寺岡宏樹; 石塚真由美, 日本獣医学会学術集会講演要旨集, 149th, 308, 2010
  Japanese
• Sources and distributions of heavy metals in Zambia: Environmental monitoring of soil and sediment contamination by heavy metals in Zambia
  IKENAKA Yoshinori; NAKAYAMA Shouta M.M; MUZANDU Kaampwe; CHOONGO Kennedy; SAKAMOTO Kentaro Q; TERAOKA Hiroki; MIZUNO Naoharu; ISHIZUKA Mayumi, 環境化学討論会講演要旨集, 18th, 134, 135, 09 Jun. 2009
  English
• アカハライモリにおけるシトクロムP450 1Aのcharacterization
  中山翔太; 石塚真由美; 田中(上野)寛子; 坂本健太郎; 藤田正一, は虫両棲類学会報, 2008, 1, 41, 42, 31 Mar. 2008
  Japanese
• 両生類,特に有尾類アカハライモリを中心としたCYP1Aのcharacterization
  中山翔太; 石塚真由美; 田中‐上野寛子; 坂本健太郎; 藤田正一, 日本獣医学会学術集会講演要旨集, 144th, 192, 27 Aug. 2007
  Japanese

• トキシコロジー（第3版）
  中山翔太, 7章 環境毒性
  朝倉書店, Mar. 2018, [Contributor]

• Effects of PCB exposure on thyroid hormone levels in serum of dogs and cats
  Kohki Takaguchi; Hiroyuki Nishikawa; Hazuki Mizukawa; Rumi Tanoue; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Shouta M; M. Nakayama; Yoshinori Ikenaka; Tatsuya Kunisue; Mayumi Ishizuka; Shinsuke Tanabe; Hisato Iwata; Kei Nomiyama
  SETAC North America 39th Annual Meeting, 04 Nov. 2018, English, Poster presentation
  [International presentation]
• Avian interspecific differences in rodenticide sensitivity: amino acid sequence and mRNA expression ratio of VKORC1 and VKORC1L1
  Shouta M.M. NAKAYAMA; Ayuko MORITA; Yoshinori IKENAKA; Yusuke K. KAWAI; Kazuki TAKEDA; Hazuki MIZUKAWA; Chihiro ISHII; Keisuke SAITO; Yukiko WATANABE; Masaki ITO; Natsuo Ohsawa; Mayumi ISHIZUKA
  SETAC North America 39th Annual Meeting. 4th ~ 8th Nov 2018, 04 Nov. 2018, English, Oral presentation
  [International presentation]
• Blood Lead (Pb) Levels and Stable Isotope Ratio among Children, Infants and Mothers in Kabwe, Zambia
  Shouta MM Nakayama; John Yabe; Haruya Toyomaki; Kaampwe Muzandu; Yared B Yohannes; Hokuto Nakata; Yoshinori Ikenaka; Hazuki Mizukawa; Takeshi Kuritani; Mitsuhiro Nakagawa; Mayumi Ishizuka
  SETAC North America 39th Annual Meeting, 04 Nov. 2018, English, Poster presentation
  [International presentation]
• Avian interspecific differences in VKOR activity and inhibition: Amino acid sequence and mRNA expression ratio of VKORC1 and VKORC1L1
  Shouta M.M. NAKAYAMA; Ayuko MORITA; Yoshinori IKENAKA; Yusuke K. KAWAI; Kazuki TAKEDA; Hazuki MIZUKAWA; Chihiro ISHII; Keisuke SAITO; Yukiko WATANABE; Masaki ITO; Natsuo Ohsawa; Mayumi ISHIZUKA
  2018 International Meeting on 22nd MDO and 33rd JSSX, 01 Oct. 2018, English, Poster presentation
  [International presentation]
• 鉄中毒を疑うコガネメキシコインコの一例
  井上春奈; 齋藤瞬; 吉澤未来; 渡部孝; 中山翔太; 池中良徳; 石塚真由美
  第66回動物園技術者研究会, 27 Sep. 2018, Japanese, Poster presentation
  [Domestic Conference]
• Inter-species differences of phase II xenobiotics metabolism enzymes in carnivorans
  Takamitsu Kondo; Yoshinori Ikenaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Yoko Mitani; Kei Nomiyama; Shinsuke Tanabe; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Oral presentation
  [International presentation]
• Vegetation status and suppression of Pb accumulation in wild lizards around Pb-Zn mine in Kabwe, Zambia
  Rio Doya; Shouta M.M. Nakayama; Hokuto Nakata; Haruya Toyomaki; John Yabe; Kaampwe Muzandu; Yared Beyene; Andrew Kataba; Golden Zyambo; Yoshitaka Uchida; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• Does dog’s behavior affect the blood lead levels in domestic dogs around lead mining area, Kabwe, Zambia?
  Haruya Toyomaki; John Yabe; Shouta M.M. Nakayama; Yared Beyene Yohannes; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Oral presentation
  [International presentation]
• Effects of zinc co-administration with lead (Pb) on Pb biodistribution in tissues of Sprague Dawley (SD) rats
  Andrew Kataba; Shouta M.M Nakayama; Yared B. Yohannes; Haruya Toyomaki; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• DNA Methylation Biomarkers in Environmental Lead-Exposed Children from Kabwe, Zambia
  Yared Beyene Yohannea; Shouta M.M; Nakayama; John Yabe; Toyomaki Haruya; Kaampwe Muzandu; Hokuto Nakata; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• Evaluation of Exposure and Toxicological Implications of Neonicotinoid Insecticides among the residents of Kumasi, Ghana
  Collins NIMAKO; Yoshinori IKENAKA; Osei AKOTO; Nesta BORTEY-SAM; Shouta M.M.NAKAYAMA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• Charcterization of CYP expression in cat-related PCBs exposure
  Kraisiri Khidkan; Hazuki Mizukawa; Yoshinori Ikenaka; Shouta M; M. Nakayama; Wageh Sobhy Darwish; Kei Nomiyama; Mitsuyoshi Takiguchi; Nozomu Yokoyama; Osamu Ichii; Shinsuke Tanabe; Mayumi Ishizuka
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• Assessment of vitamin K epoxide reductase by in vitro kinetic analysis & in silico docking simulation for evaluation of rodenticide sensitivity
  Kazuki TAKEDA; Yoshinori IKENAKA; Kazuyuki D. TANAKA; Shouta M.M. NAKAYAMA; Tsutomu TANIKAWA; Hazuki Mizukawa; Mayumi ISHIZUKA
  The 6th Sapporo Summer Symposium for One Health (6th SaSSOH), 20 Sep. 2018, English, Poster presentation
  [International presentation]
• Evaluation of Neonicotinoid Insecticide Exposure and Toxicity among some residents of Kumasi, Ghana
  Collins NIMAKO; Yoshinori IKENAKA; Osei AKOTO; Nesta BORTEY-SAM; Shouta M.M. NAKAYAMA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  Society for Environmental Toxicology and Chemistry, Asia-Pacifi 2018 (SETAC-AP2018), 16 Sep. 2018, English, Poster presentation
  [International presentation]
• グルクロン酸転移酵素UGT1A6と哺乳類の食性の関係
  佐野花澄; 池中良徳; 近藤誉充; 川合佑典; 中山翔太; 水川葉月; 石塚真由美
  第161回日本獣医学会学術集会, 11 Sep. 2018, Japanese, Oral presentation
  [Domestic Conference]
• オジロワシを中心とした鳥類の食性による腸内細菌叢変動と影響の解析
  山田尚輝; 中山翔太; 水川葉月; 小笠原浩平; 渡邊有希子; 齊藤慶輔; 伊藤真輝; 大澤夏生; 竹中康進; 小松謙之; 千葉茜; 内田義崇; 池中良徳; 石塚真由美
  第161回日本獣医学会学術集会, 11 Sep. 2018, Japanese, Oral presentation
  [Domestic Conference]
• 誘導体化液体クロマトグラフィー質量分析法（LC/MS法）によるエクイリン・エクイレニンを中心とするステロイドホルモン多成分一斉分析メソッドの開発及びその応用
  三津橋嵩史; 池中良徳; 一瀬貴大; Aksorn Saengtienchai; 中山翔太; 水川葉月; 河合正人; 南保泰雄; 石塚真由美
  第161回日本獣医学会学術集会, 11 Sep. 2018, Japanese, Oral presentation
  [Domestic Conference]
• 小笠原諸島における殺鼠剤散布が野生動物に及ぼす影響の解明
  中山翔太; 川合佑典; 武田一貴; 池中良徳
  小笠原諸島返還50周年記念 みんなの近くの世界遺産＜返還50周年記念講演会＞, 11 Sep. 2018, Japanese, Poster presentation
  [Domestic Conference]
• ザンビア共和国カブウェ鉱床地域における鉛汚染問題解決に向けて：10年間の研究成果と今後の課題
  中山翔太
  平成30年度育志賞研究発表会, 06 Sep. 2018, Japanese, Poster presentation
  [Domestic Conference]
• 国内に生息する野生鳥類における鉛曝露状況の解明
  石井 千尋; 池中 良徳; 中山 翔太; 齊藤 慶輔; 渡辺 有希子; 小笠原 浩平; 水川 葉月; 石塚 真由美
  第24回日本野生動物医学会大会, 31 Aug. 2018, Japanese, Poster presentation
  [Domestic Conference]
• 鰭脚類を中心とした食肉目の薬物代謝酵素である硫酸転移酵素の種差解明
  近藤 誉充; 池中 良徳; 中山 翔太; 水川 葉月; 三谷 曜子; 田辺 信介; 野見山 桂; 石塚 真由美
  第24回日本野生動物医学会大会, 31 Aug. 2018, Japanese, Poster presentation
  [Domestic Conference]
• 殺鼠剤に弱い野生動物種を探る：標的分子ビタミンKエポキシド還元酵素(VKOR)の鳥類における特徴および種差
  中山翔太; 森田鮎子; 池中良徳; 石井千尋; 水川葉月; 武田一貴; 川合佑典; 齊藤慶輔; 渡邊有希子; 大澤夏生; 伊藤真輝; 石塚真由美
  第24回日本野生動物医学会大会, 31 Aug. 2018, Japanese, Poster presentation
  [Domestic Conference]
• PCR法による鳥類の雌雄判定：孵化前雌雄判定の試みとその課題
  中山翔太; 池中良徳; 石井千尋; 水川葉月; 川合佑典; 平野なぎ沙; 齊藤慶輔; 渡邊有希子; 大澤夏生; 伊藤真輝; 中村亮平; 石塚真由美
  第24回日本野生動物医学会大会, 31 Aug. 2018, Japanese, Poster presentation
  [Domestic Conference]
• Contamination status and global comparison of organohalogen compounds and their related compounds in the pet cats from Thailand
  Makoto Shimasaki; Kei Nomiyama; Hazuki Mizukawa; Aksorn Saengtienchai; Araya Ngamchirttakul; Disdanai Pencharee; Yoshinori Ikenaka; Shouta MM Nakayama; Tatsuya Kunisue; Shinsuke Tanabe
  38th International Symposium on Halogenated Persistent Organic Pollutants (POPs) : DIOXIN 2018, 26 Aug. 2018, English, Poster presentation
  [International presentation]
• Pilot study on the toxicological assessment of organohalogen compounds in pet cat (Felis catus) serum using metabolomics approach
  Kei Nomiyama; Aifumi Eguchi; HazukiMizukawa; Yasuo Yamamoto; Hiroyuki Nishikawa; Mitsuyoshi Takiguchi; Shouta MM Nakayama; Yoshinori Ikenaka; Mayumi Isizuka; Shinsuke Tanabe
  38th International Symposium on Halogenated Persistent Organic Pollutants (POPs) : DIOXIN 2018, 26 Aug. 2018, English, Oral presentation
  [International presentation]
• Effects of Polychlorinated Biphenyls (PCBs) in Cats: Exhaustive Gene Expression Analysis Approach
  Hazuki Mizukawa; Kraisiri Khidkhan; Yoshinori Ikenaka; Shouta M.M. Nakayama; Kei Nomiyama; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Sainnoxoi Tsend-ayush; Shinsuke Tanabe; Mayumi Ishizuka
  38th International Symposium on Halogenated Persistent Organic Pollutants (POPs) : DIOXIN 2018, 26 Aug. 2018, English, Oral presentation
  [International presentation]
• Tissue distribution and CYP expression related-PCBs exposure in cats
  Kraisiri Khidkan; Hazuki Mizukawa; Yoshinori Ikenaka; Shouta M; M. Nakayama; Wageh Sobhy Darwish; Kei Nomiyama; Mitsuyoshi Takiguchi; Nozomu Yokoyama; Osamu Ichii; Shinsuke Tanabe; Mayumi Ishizuka
  38th International Symposium on Halogenated Persistent Organic Pollutants (POPs) : DIOXIN 2018, 26 Aug. 2018, English, Oral presentation
  [International presentation]
• The estimation of potential PCBs toxicity in cats by evaluating CYP450 expressions
  Kraisiri Khidkan; Hazuki Mizukawa; Yoshinori Ikenaka; Shouta M; M. Nakayama; Kei Nomiyama; Mitsuyoshi Takiguchi; Nozomu Yokoyama; Osamu Ichii; Shinsuke Tanabe; Mayumi Ishizuka
  38th International Symposium on Halogenated Persistent Organic Pollutants (POPs) : Pre- Dioxin 2018 Students’ Symposium, 25 Aug. 2018, English, Poster presentation
  [International presentation]
• Evaluation of performance of half-burnt dolomite as an adsorbent in laboratory and pilot-scale tests
  Keigo Kimura; Kenta Noto; Jin Ota; Toshifumi Igarashi; Mayumi Ito; Tsutomu Sato; Meki Chirwa; Imasiku Nyambe; Taonga Chirwa; Shouta M.M. Nakayama; Hokuto Nakata; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• The impact of elevated blood lead levels in Kabwe children on the health-related quality of life in their mothers
  Harukazu Tohyama; Wakako Fujita; Shojiro Yamasaka; Natsumi Nagai; Shouta M.M. Nakayama; Hokuto Nakata; Mayumi Ishizuka; Takahiko Yohida; John Yabe; Nosiku Munyinda; Doreen Sakala; Takeshi Saito
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Importance of Vegetation in Reducing Pb Accumulation in Wild Lizards around a Pb-Zn Mine in Kabwe, Zambia
  Rio Doya; Shouta M.M. Nakayama; Hokuto Nakata; Haruya Toyomaki; John Yabe; Kaampwe Muzandu; Yared Beyene; Andrew Kataba; Golden Zyambo; Yoshitaka Uchida; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Monitoring of Dog’s Behavior using GPS and their blood lead levels around lead mining area
  Haruya Toyomaki; John Yabe; Shouta M.M. Nakayama; Yared Beyene Yohannes; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Relationship between blood lead levels in infants and mothers around lead mining area, Kabwe, Zambia
  Haruya Toyomaki; John Yabe; Kaampwe Muzandu; Shouta M.M. Nakayama; Yared Beyene Yohannes; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Takeshi Kuritani; Mitsuhiro Nakagawa; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Ameliorative effect of Moringa Oleifera on Pb-induced toxicity in rat
  Hokuto Nakata; Andrew Kataba; Haruya Toyomaki; Rio Doya; Shouta M.M; Nakayama; John Yabe; Kaampwe Muzandu; Golden Zyambo; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• The trend of elevated blood lead levels in Kabwe residents
  Hokuto Nakata; John Yabe; Shouta M.M. Nakayama; Kaampwe Muzandu; Yared Beyene Yohannes; Haruya Toyomaki; Hazuki Mizukawa; Yoshinori Ikenaka; Russel Dowling; Jack Caravanos; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Effects of zinc (Zn) supplementation on lead (Pb) accumulation in tissues of Sprague Dawley (SD) rats
  Andrew Kataba; Shouta M.M Nakayama; Yared B. Yohannes; Haruya Toyomaki; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Gene Polymorphism and DNA Methylation Patterns of Lead Biomarker Gene in Environmental Lead Exposed Children from Kabwe, Zambia
  Yared Beyene Yohannes; Shouta M.M; Nakayama; John Yabe; Haruya Toyomaki; Andrew Kataba; Kaampwe Muzandu; Hokuto Nakata; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LA-ICP-MS) reveals distribution of Pb in mice organs
  Shouta M.M. Nakayama; Masao Togao; Yoshinori Ikenaka; Hazuki Mizukawa; Yoshiki Makino; Ayano Kubota; Takehisa Matsukawa; Kazuhito Yokoyama; Takafumi Hirata; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• KAbwe Mine Pollution Amelioration Initiative ~KAMPAI Project~
  Shouta M.M; Nakayama; John Yabe; Kaampwe Muzandu; Yoshitaka Uchida; Benson Chishala; Mayumi Ito; Toshifumi Igarashi; Hokuto Nakata; Imasiku A. Nyambe; Mayumi Ishizuka
  2nd International KAMPAI Symposium & JST Mid-term Evaluation Meeting, 14 Aug. 2018, English, Poster presentation
  [International presentation]
• 食肉目動物での第II 相抱合酵素の遺伝的性状および酵素学的性状の解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美
  第45回 日本毒性学会学術年会, 18 Jul. 2018, Japanese, Oral presentation
  [Domestic Conference]
• スーパーラットは何が「スーパー」なのか？ 〜東京の殺鼠剤抵抗性クマネズミにおける抵抗性獲得機序の探索〜
  武田 一貴; 池中 良徳; 田中 和之; 中山 翔太; 谷川 力; 水川 葉月; 石塚 真由美
  第45回 日本毒性学会学術年会, 18 Jul. 2018, Japanese, Poster presentation
  [Domestic Conference]
• ザンビア共和国カブウェ鉱床地域における鉛汚染問題：10年間の研究結果と今後の課題
  中山翔太; John Yabe; 池中良徳; Kaampwe Muzandu; Kennedy Choongo; 中田北斗; 豊巻治也; Yared Beyene; Andrew Kataba; Golden Zyambo; 栗谷豪; 中川光弘; 水川葉月; 石塚真由美
  第45回 日本毒性学会学術年会, 18 Jul. 2018, Japanese, Oral presentation
  [Domestic Conference]
• ポリ塩化ビフェニル曝露によるイヌ・ネコの甲状腺ホルモン恒常性への影響
  髙口倖暉; 野見山桂; 西川博之; 水川葉月; 田上瑠美; 横山望; 市居修; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 岩田久人; 国末達也; 田辺信介
  第45回日本毒性学会学術年会, 18 Jul. 2018, Japanese, Poster presentation
  [Domestic Conference]
• Current Trends of Childhood Blood Lead Levels and Exposure Patterns in Kabwe, Zambia
  John Yabe; Haruya Toyomaki; Shouta MM Nakayama; Yared B Yohannes; Hokuto Nakata; Kaampwe Muzandu; Andrew Kataba; Jack Caravanos; Yoshinori Ikenaka; Mayumi Ishizuka
  9th International Conference on Children and the Environment (INCHES), 27 Jun. 2018, English, Invited oral presentation
  [Invited], [International presentation]
• KAbwe Mine Pollution Amelioration Initiative ~KAMPAI~
  Shouta M.M. NAKAYAMA; Yoshinori IKENAKA; Hokuto NAKATA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  2018（平成30）年度 海外学術調査フォーラム, 16 Jun. 2018, English, Poster presentation
  [Domestic Conference]
• Trace Elemental Profiles of Serum and Cerebrospinal Fluid in Dogs with Idiopathic Epilepsy
  Kazuyoshi Sasaoka; Hiroshi Ohta; Hazuki Mizukawa; Shouta Nakayama; Noboru Sasaki; Keitaro Morishita; Yoshinori Ikenaka; Mayumi Ishizuka; Mitsuyoshi Takiguchi
  2018 ACVIM Forum (American College of Veterinary Internal Medicine), 14 Jun. 2018, English, Poster presentation
  [International presentation]
• Utility evaluation for stable Lead isotope ratios for source identification and verifying biological fractionation of lead isotopes in goats and chickens
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh Sobhy Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  7th Zambia Water Forum and Exhibition, 12 Jun. 2018, English, Invited oral presentation
  [Invited], [International presentation]
• Distribution of Pb in mice organs using bioimaging by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)
  Shouta M.M. Nakayama; Masao Togao; Yoshinori Ikenaka; Hazuki Mizukawa; Yoshiki Makino; Ayano Kubota; Takehisa Matsukawa; Kazuhito Yokoyama; Takafumi Hirata; Mayumi Ishizuka
  7th Zambia Water Forum and Exhibition, 12 Jun. 2018, English, Invited oral presentation
  [Invited], [International presentation]
• Current trends of childhood Blood lead levels and Exposure patterns in Kabwe
  John Yabe; Shouta M.M. Nakayama; Haruya Toyomaki; Yared Beyene Yohannes; Hokuto Nakata; Kaampwe Muzandu; Andrew Kataba; Golden Zyambo; Nosiku S. Munyinda; Kennedy Choongo; Tiza Mfune; Paul Mukuka; Jack Caravanos; Mayumi Ishizuka
  7th Zambia Water Forum and Exhibition, 12 Jun. 2018, English, Invited oral presentation
  [Invited], [International presentation]
• The trend of elevated blood lead levels in mining area, Kabwe, Zambia
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Kaampwe Muzandu; Yared B. Yohannes; Haruya Toyomaki; Andrew Kataba; Golden Zyambo; Hazuki Mizukawa; Yoshinori Ikenaka; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  日本アフリカ学会第５５回学術大会, 26 May 2018, English, Oral presentation
  [International presentation]
• Analysis of the amino acid metabolome in p,p’-DDT exposed chickens
  Lesa A Thompson; Isabel M Vincent; Yoshinori Ikenaka; Stefan K Weidt; Wageh S Darwish; Shouta MM Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• マラリアベクターコントロールにおけるDDTの使用実態とリスク評価
  池中良徳; リサ トンプソン; ダルウィッシュ ワギ; ヨハネス ヤレド; ファンファーレン ヨハン; スミッツ ニコ; ヴェペナー ヴィクター; 中山翔太; 水川葉月; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• ネオニコチノイド系殺虫剤のヒト健康影響評価問題点の整理と今後の研究課題
  池中良徳; 一瀬貴大; ニマコ コリンズ; 市川剛; 水川葉月; 中山翔太; 有薗幸司; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• 誘導体化LC/MS/MS法による血漿中のステロイドホルモンおよびその抱合体代謝物35種類の一斉分析法の開発とその応用
  一瀬貴大; 池中良徳; Aksorn Saengtienchai; 中山翔太; 水川葉月; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Poster presentation
  [Domestic Conference]
• 野生哺乳類における硫酸転移酵素の動物種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• タイ王国におけるペットネコ血清およびペットフード中有機ハロゲン化合物と類縁化合物の汚染実態
  島崎真琴; 野見山桂; 水川葉月; Aksorn Saengtienchai; Araya Ngamchirttakul; Disdanai Pencharee; 石塚真由美; 池中良徳; 中山翔太; 国末達也; 田辺信介
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• 血清中メタボローム解析によるペットネコ（Felis catus）の有機ハロゲン化合物毒性影響評価
  野見山桂; 江口哲史; 水川葉月; 山本恭央; 西川博之; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 田辺信介
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• ネコのin vivo BDE209長期曝露試験による体内動態の解明および甲状腺ホルモンへの影響評価
  田中啓介; 野見山桂; 水川葉月; 高口倖暉; 田上瑠美; 横山望; 市居修; 滝口満喜; 笹岡一慶; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• 有機ハロゲン化合物曝露によるネコの生化学マーカーの変化および甲状腺機能に及ぼす影響評価
  水川葉月; Kraisiri Khidkhan; 高口倖暉; 横山望; 市居修; 滝口満喜; 笹岡一慶; 池中良徳; 中山翔太; 野見山桂; 田辺信介; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• Characteristics of CYP450 expression in cat exposed PCBs: Estimating the potential toxicity
  Kraisiri Khidkhan; Hazuki Mizukawa; Kei Nomiyama; Yoshinori Ikenaka; Shota M; M. Nakayama; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Hiroyuki Nishikawa; Keisuke Tanaka; Kohki Takiguchi; Shinsuke Tanabe; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• HPLC-APCI-MSを用いたビタミンKの網羅的検出とin vitroビタミンKエポキシド還元酵素活性の評価
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• 鉛鉱床地域における野生トカゲ亜目の生体内金属類濃度に影響を与える環境要因の解析
  銅谷理緒; 中山翔太; 中田北斗; 豊巻治也; Yabe John; Muzandu Kaampwe; Beyene Yared; Kataba Andrew; yambo Golden; 水川 葉月; 池中 良徳; 石塚 真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• GPS装置を用いた鉛鉱床地域のイヌの行動のモニタリングと鉛曝露の関係性
  豊巻治也; Yabe John; 中山翔太; Beyene Yared; 水川葉月; 池中良徳; 中田北斗; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• Utility of Pb isotopes for source identification and species differences of Pb isotope biological fractionation
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh S. Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• Evaluation of Neonicotinoid Insecticide exposure in humans living in the Kumasi city, Ghana
  Collins Nimako; Yoshinori Ikenaka; Osei Akoto; Nesta Bortey-Sam; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• Lead (Pb) accumulation in tissues of Sprague Dawley (SD) rats following sub chronic Lead-Zinc exposure
  Andrew Kataba; Shouta Nakayama; Yared B. Yohannes; Haruya Toyomaki; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• Blood Lead Levels Among the General Population in Kabwe, Zambia
  Yared B. Yohannes; Shouta Nakayama; John Yabe; Hokuto Nakata; Haruya Toyomaki; Kaampwe Muzandu; Andrew Kataba; Yoshinori Ikenaka; Hazuki Mizukawa; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  第27回環境化学討論会, 22 May 2018, English, Oral presentation
  [Domestic Conference]
• 非侵襲的に採取可能な乳幼児の糞便における鉛安定同位体比を用いた鉛暴露経路の推定
  中山翔太; 豊巻治也; John Yabe; Kaampwe Muzandu; 中田北斗; 栗谷豪; 中川光弘; 水川葉月; 池中良徳; 石塚真由美
  第27回環境化学討論会, 22 May 2018, Japanese, Oral presentation
  [Domestic Conference]
• クロミンククジラ未成熟雌のヒゲ板安定同位体比を用いた摂餌履歴推定
  打田茉由果; 鈴木一平; 石塚真由美; 池中良徳; 中山翔太; 水川葉月; 田村 力; 坂東武治; 小西健志; 三谷曜子
  平成30年度日本水産学会春季大会, 26 Mar. 2018, English, Oral presentation
  [Domestic Conference]
• Novel Mechanism of Rodenticide (warfarin) Resistance of Wild Rats in Tokyo ~ Enhanced Pentose Phosphate Pathway Causes Rapid Metabolism of Warfarin ~
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  Society of Toxicology’s 57th Annual Meeting and ToxExpo, 11 Mar. 2018, English, Poster presentation
  [International presentation]
• Lead levels in eggs in Kabwe, Zambia: implication of human exposure
  Haruya Toyomaki; John Yabe; Shouta M.M. Nakayama; Yared B. Yohannes; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Takeshi Kuritani; Mitsuhiro Nakagawa; Mayumi Ishizuka
  Society of Toxicology’s 57th Annual Meeting and ToxExpo, 11 Mar. 2018, English, Poster presentation
  [International presentation]
• Migratory seabirds are responsible for mercury biotransport from marine to terrestrial ecosystems
  Shoji, A; K. H. Elliott; S. Aris-Brosou; H. Mizukawa; S. Nakayama; Y. Ikenaka; M. Ishizuka; T. Kuwae; K. Watanabe; Y. Watanuki
  The 45th Pacific Seabird Group Annual Meeting, 21 Feb. 2018, English, Oral presentation
  [International presentation]
• 犬の特発性てんかんにおける血中及び脳脊髄液中微量元素濃度の検討
  笹岡一慶; 大田寛; 水川葉月; 中山翔太; 佐々木東; 森下啓太郎; 池中良徳; 石塚真由美; 滝口満喜
  第14回 日本獣医内科学アカデミー学術大会（JCVIM 2018）, 16 Feb. 2018, Oral presentation
  [Domestic Conference]
• ザンビア・カブエ鉱床における鉛汚染問題とその解決に向けた取り組み-KAbwe Mine Pollution Amelioration Initiative (KAMPAI Project)
  中山翔太; 水川葉月; 池中良徳; 石塚真由美
  第3回 北大部局間横断シンポジウム, 26 Jan. 2018, Japanese, Oral presentation
  [Domestic Conference]
• スーパーラットは高NADPH産生能を持つ〜東京の殺鼠剤抵抗性ラットにおける抵抗性獲得機序の解明〜
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美
  第3回 北大部局間横断シンポジウム, 26 Jan. 2018, Japanese, Poster presentation
  [Domestic Conference]
• 幼児および新生児におけるネオニコチノイド系殺虫剤の曝露実態
  池中良徳; 宮原裕一; 一瀬貴大; 中山翔太; 水川葉月; 市川剛; 遠山千春; 石塚真由美
  環境ホルモン学会第20回研究発表会, 11 Dec. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Evaluation of indoor residual spraying DDT for mosquito control: Tissue distribution and gene expression profiling in rat tissues
  Emmanuel Temiotan; Ogbomida; Alex Ajeh Enuneku; Yoshinori Ikenaka; Yared Beyene Yohannes; Wageh Sobhy Darwish; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  環境ホルモン学会第20回研究発表会, 11 Dec. 2017, Japanese, Poster presentation
  [Domestic Conference]
• ポリ塩化ビフェニル（PCBs）がネコの甲状腺機能に及ぼす影響
  水川葉月; 高居名菜; 野見山桂; 高口倖暉; 横山望; 市居修; 滝口満喜; 池中良徳; 中山翔太; 石塚真由美
  環境ホルモン学会第20回研究発表会, 11 Dec. 2017, Japanese, Poster presentation
  [Domestic Conference]
• 東京のワルファリン抵抗性ラットの抵抗性獲得機序の解明：ペントースリン酸経路の亢進を通したワルファリン代謝の活性化
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  2017年度生命科学系学会合同年次大会（ConBio2017）, 06 Dec. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Russell Dowling, Jack Caravanos, Hokuto Nakata, Mayumi Ishizuka, Elevated Blood Lead Levels among Children, Infants and Mothers in Kabwe, Zambia
  Yared Beyene Yohannes; John Yabe; Shouta M.M. Nakayama; Haruya Totomaki; Kaampwe Muzandu; Yoshinori Ikenaka; Hazuki Mizukawa
  SETAC North America 38th Annual Meeting, 11 Nov. 2017, English, Oral presentation
  [International presentation]
• Biochemical Alterations due to PCBs and PBDEs Exposures in Cats
  Kraisiri Khidkhan; Hazuki Mizukawa; Kei Nomiyama; Yoshinori Ikenaka; Shouta M; M. Nakayama; Nozomu Yokoyama; Kazuyoshi Sasaoka; Osamu Ichii; Mitsuyoshi Takiguchi; Hiroyuki Nishikawa; Keisuke Tanaka; Kohki Takiguchi; Shinsuke Tanabe; Mayumi Ishizuka
  SETAC North America 38th Annual Meeting, 11 Nov. 2017, English, Poster presentation
  [International presentation]
• Evaluation of utility for stable lead isotope ratios to identify lead sources and verifying biological fractionation of lead isotopes in goats and chickens
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh Sobhy Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  SETAC North America 38th Annual Meeting, 11 Nov. 2017, English, Poster presentation
  [International presentation]
• Local distribution of Pb in mice using bioimaging by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)
  Shouta MM Nakayama; Masao Togao; Yoshinori Ikenaka; Hazuki Mizukawa; Yoshiki Makino; Ayano Kubota; Takehisa Matsukawa; Kazuhito Yokoyama; Takafumi Hirata; Mayumi Ishizuka
  1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 06 Nov. 2017, English, Poster presentation
  [International presentation]
• Practical system integration for local community participation in lead contamination assessment in Kabwe, Zambia
  Shinsaku Nakamura; Kazuyo Hirose; Tomomi Takeda; Yoshitaka Uchida; Hokuto Nakata; Shouta MM Nakayama; Mayumi Ishizuka; John Yabe; Mayumi Ito; Toshifumi Igarashi
  1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 06 Nov. 2017, English, Poster presentation
  [International presentation]
• Reliability of stable lead isotope analysis for lead source identification and verifying biological fractionation of lead isotopes in goats and chicken
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh S Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 06 Nov. 2017, English, Poster presentation
  [International presentation]
• Extent of lead exposure in mothers and infants living around a “closed” lead mining area, Kabwe, Zambia
  Haruya Toyomaki; John Yabe; Shouta M.M. Nakayama; Yared B. Yohannes; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 06 Nov. 2017, English, Oral presentation
  [International presentation]
• Current trends of blood lead levels in Kabwe, Zambia
  Yared Beyene Yohannes; John Yabe; Shota M.M. Nakayama; Haruya Toyomaki; Hokuto Nakata; Kaampwe Muzandu; Andrew Kataba; Golden Zyambo; Hazuki Mizukawa; Yoshinori Ikenaka; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  1st International KAMPAI Symposium on Sustainable Management of Resources and Environment in the 21st Century, 06 Nov. 2017, English, Oral presentation
  [International presentation]
• Discovery of renal biomarkers in birds by transcriptome analysis and glycomics analysis following kidney injury in chicken model
  Chihiro Ishii; Yoshinori Ikenaka; Yusuke K. Kawai; Osamu Ichii; Shouta. M; M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The 10th International Meeting of the Asian Society of Conservation Medicine (ASCM), 20 Oct. 2017, English, Poster presentation
  [International presentation]
• Indoor exposure for polychlorinated biphenyls (PCBs) in domestic cats ~Pilot study of Mongolian pet cat~
  Hazuki Mizukawa; Yoshinori Ikenaka; Tsend-Ayush Sainnoxoi; Kohki Takaguchi; Kei Nomiyama; Shouta M.M. Nakayama; Mayumi Ishizuka
  The 2nd Symposium on the Improvement of Diagnosis and Prevention of some Diseases Caused by Environmental Change, 14 Oct. 2017, English, Oral presentation
  [International presentation]
• “First, do no harm” ? balancing the benefits of malaria control against the toxic effects of DDT use
  Lesa THOMPSON; Yoshinori IKENAKA; Yared YOHANNES; Atnafu ASSEFA; Johan VAN VUREN; Victor WEPENER; Nico SMIT; Wynand VLOK; Wageh Sobhy DARWISH; Shouta NAKAYAMA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Oral presentation
  [International presentation]
• Drug metabolism enzymes in Carnivora species
  Takamitsu Kondo; Yoshinori Ikenaka; Shouta M.M. Nakayama; Yusuke K. Kawai; Hazuki Mizukawa; Yoko Mitani; Kei Nomyama; Shinsuke Tanabe; Mayumi Ishizuka
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Poster presentation
  [International presentation]
• Discovery of renal biomarker in birds by transcriptome analysis of kidney tissues and glycomics analysis of plasma following renal damage in chicken model
  Chihiro Ishii; Yoshinori Ikenaka; Yusuke K. Kawai; Osamu Ichii; Shouta. M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Poster presentation
  [International presentation]
• Blood Lead Levels in chickens and dogs around lead mining area, Kabwe, Zambia
  Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; John Yabe; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Poster presentation
  [International presentation]
• Effects of Organohalogen Compounds on Serum Biochemical Profiles in Cats
  Kraisiri Khidkhan; Hazuki Mizukawa; Kei Nomiyama; Yoshinori Ikenaka; Shota M.M. Nakayama; Nozomu Yokoyama; Kazuyoshi Sasaoka; Osamu Ichii; Mitsuyoshi Takiguchi; Hiroyuki Nishikawa; Keisuke Tanaka; Kohki Takiguchi; Shinsuke Tanabe; Mayumi Ishizuka
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Poster presentation
  [International presentation]
• Nobel investigation of mechanism of rodenticide resistance ~ enhanced pentose phosphate pathway causes rapid metabolism of warfarin ~
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The 5th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2017, English, Oral presentation
  [International presentation]
• 海鳥を介した汚染物質輸送
  庄子晶子; K. Elliott; S. Aris-Brosou; 水 川葉月; 中山翔太; 池中良徳; 石塚真由美; 桑江朝比呂; 渡辺謙太; 綿貫豊
  日本鳥学会2017年度大会, 15 Sep. 2017, Japanese, Oral presentation
  [Domestic Conference]
• 鳥類におけるグルクロン酸抱合能の種差の解明と化学物質感受性の推定
  新屋惣; 池中良徳; 中山翔太; 水川葉月; 伊藤真輝; 高江洲昇; 齊藤 慶輔; 渡邊 有希子; 石塚 真由美
  日本鳥学会2017年度大会, 15 Sep. 2017, Japanese, Poster presentation
  [Domestic Conference]
• 鳥類医学の発展に向けた新規腎障害マーカーの探索
  石井千尋; 池中良徳; 川合佑典; 市居修; 中山翔太; 西村紳一郎; 大橋哲; 田中誠一; 齊藤慶輔; 渡邊有希子; 水川葉月; 石塚真由美
  日本鳥学会2017年度大会, 15 Sep. 2017, Japanese, Poster presentation
  [Domestic Conference]
• 東京由来殺鼠剤抵抗性ラットを用いた新規抵抗性獲得機序の解明 ~ペントースリン酸経路の亢進による殺鼠剤代謝能の活性化~
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美
  第160回日本獣医学会学術年会, 12 Sep. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Wild rat’s bio-distribution analysis for pesticide DDT from South Africa
  Tetsuro Ogawa; Yoshinori Ikenaka; Yared B Yohannes; Lesa Thompson; Johan van Vuren; Victor Wepener; Nico J Smit; Wynand Vlok; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Poster presentation
  [International presentation]
• UDP-glucuronosyltransferase (UGT) 2B genetic feature and activities in Carnivores
  Takamitsu Kondo; Yoshinori Ikenaka; Shouta M.M. Nakayama; Yusuke K. Kawai; Hazuki Mizukawa; Yoko Mitani; Kei Nomyama; Shinsuke Tanabe; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Oral presentation
  [International presentation]
• Short-term or long-term in vivo exposure to organohalogen compounds in cats: Elucidate the metabolic capacities and effects on thyroid function
  Hazuki Mizukawa; Yoshinori Ikenaka; Shouta M.M. Nakayama; Kei Nomiyama; Misaki Maehara; Aksorn Saengtienchai; Tsend-ayush Sainnoxoi; Kraisiri Khidkhan; Nozomu Yokoyama; Kazuyoshi Sasaoka; Osamu Ichii; Mitsuyoshi Takiguchi; Khoki Takaguchi; Hiroki Nishikawa; Nana Takai; Shinsuke Tanabe; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Oral presentation
  [International presentation]
• The relationship of Blood Lead Levels between mothers and infants in Kabwe, Zambia
  Haruya Toyomaki; John Yabe; Shouta M.M. Nakayama; Yared B. Yohannes; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Hokuto Nakata; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Oral presentation
  [International presentation]
• Trends of childhood blood lead levels and remedial options in Kabwe, Zambia
  ohn Yabe; Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; Kaampwe Muzandu; Andrew Kataba; Kennedy Choongo; Russell Dowling; Jack Caravanos; Yoshinori Ikenaka; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Oral presentation
  [International presentation]
• Heavy metal residues in some ready-to-eat meat products marketed in Egypt
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  9th International Toxicology Symposium in Nigeria, 07 Sep. 2017, English, Oral presentation
  [International presentation]
• 全国規模での鳥類への鉛曝露：曝露指標として骨の利用の可能性
  石井千尋; 中山翔太; 池中良徳; Kataba Andrew; 齊藤慶輔; 渡辺有希子; 槇納好岐; 松川岳久; 久保田章乃; 横山和仁; 水川葉月; 平田岳史; 石塚真由美
  第23回日本野生動物医学会大会, 01 Sep. 2017, Japanese, Oral presentation
  [Domestic Conference]
• エストロジェン類高感度分析法の開発と野生動物におけるスクリーニング
  新屋惣; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 伊藤真輝; 高江洲昇; 大澤夏生; 綿貫豊; 石塚 真由美
  第23回日本野生動物医学会大会, 01 Sep. 2017, Japanese, Poster presentation
  [Domestic Conference]
• in vivo exposure to PCBs in cats: Analysis of metabolic capacities and effects on the thyroid hormone homeostasis
  Hazuki Mizukawa; Kei Nomiyama; Hiroyuki Nishikawa; Misaki Maehara; Nana Takai; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Yoshinori Ikenaka; Shouta M.M. Nakayama; Kohki Takaguchi; Shinsuke Tanabe; Mayumi Ishizuka
  37th International Symposium on Halogenated Persistent Organic Pollutants (DIOXIN 2017), 20 Aug. 2017, English, Oral presentation
  [International presentation]
• Utility evaluation for stable Pb isotopes analysis using potential sentinel animals to identify Pb pollution sources
  Hokuto Nakata; Shouta M.M; Nakayama; John Yabe; Allan Liazambi; Hazuki Mizukawa; Wageh Sobhy Darwish; Yoshinori Ikenaka; Mayumi Ishizuka
  International Conference on Geology, Mining, Mineral and Groundwater Resources of the Sub-Saharan Africa, 11 Jul. 2017, English, Oral presentation
  [International presentation]
• 幼児のネオニコチノイド系農薬の曝露評価に関する研究
  池中良徳; 宮原裕一; 一瀬貴大; 八木橋美緒; 中山翔太; 水川葉月; 平久美子; 有薗幸司; 高橋圭介; 加藤恵介; 遠山千春; 石塚真由美
  第44回日本毒性学会学術年会, 10 Jul. 2017, Japanese, Oral presentation
  [Domestic Conference]
• 肝灌流試験、in vitro酵素活性試験による東京由来ワルファリン抵抗性クマネズミのワルファリン代謝能の解明
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美
  第44回日本毒性学会学術年会, 10 Jul. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Studies on polycyclic aromatic hydrocarbons formation in heat-treated meat
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  第44回日本毒性学会学術年会, 10 Jul. 2017, English, Oral presentation
  [Domestic Conference]
• ポリ塩化ビフェニル（PCBs）のin vivo暴露によるネコの異物代謝解明と甲状腺ホルモンへの影響評価
  水川葉月; 前原美咲; 横山望; 市居修; 滝口満喜; 野見山桂; 西川博之; 池中良徳; 中山翔太; 高口倖暉; 田辺信介; 石塚真由美
  第44回日本毒性学会学術年会, 10 Jul. 2017, Japanese, Poster presentation
  [Domestic Conference]
• Inveatigation of biochemical changes in cat exposed organohalogen compounds
  Kraisiri Khidkhan; Hazuki Mizukawa; Kei Nomiyama; Yoshinori Ikenaka; Shota M; M. Nakayama; Nozomu Yokoyama; Kazuyoshi Sasaoka; Osamu Ichii; Mitsuyoshi Takiguchi; Hiroyuki Nishikawa; Keisuke Tanaka; Kohki Takiguchi; Shinsuke Tanabe; Mayumi Ishizuka
  the 19th International Symposium on Pollutant Responses in Marine Organisms (PRIMO 19), 30 Jun. 2017, English, Poster presentation
  [International presentation]
• UDP-glucuronosyltransferase (UGT) among Pinnipedia and other carnivores
  Takamitsu Kondo; Yoshinori Ikenaka; Shouta M.M. Nakayama; Yusuke K. Kawai; Hazuki Mizukawa; Yoko Mitani; Kei Nomiyama; Shinsuke Tanabe; Mayumi Ishizuka
  the 19th International Symposium on Pollutant Responses in Marine Organisms (PRIMO 19), 30 Jun. 2017, English, Oral presentation
  [International presentation]
• 高次栄養段階生物への化学物質の感受性の種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳
  2017年度第31回環境ホルモン学会講演会, 16 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Introduction of “The project for Visualization of impact of chronic / latent chemical hazard and Geo-Ecological Remediation” in Kabwe, Zambia
  Hokuto Nakata; Yoshitaka Uchida; Kaampwe Muzandu; Kawawa Banda; Shouta M.M; Nakayama; John Yabe; Toshifumi Igarashi; Mayumi Ito; Imasiku Nyambe; Mayumi Ishizuka
  The sixth Zambia Water Forum and Exhibition, 12 Jun. 2017, English, Oral presentation
  [International presentation]
• 幼児における尿中ネオニコチノイド濃度とその曝露実態の解明
  池中良徳; 宮原裕一; 一瀬貴大; 八木橋美緒; 中山翔太; 水川葉月; 遠山千春; 石塚真由美
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• In situ肝灌流試験によるワルファリン抵抗性クマネズミでのワルファリン代謝能の解明
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Poster presentation
  [Domestic Conference]
• A Pilot Study on Exposure of Lead (Pb) and Its Blood Level Burden in Children from Kabwe, Zambia: Implication to the General Population
  Yared B. Yohannes; Shouta M.M. Nakayama; Haruya Toyomaki; John Yabe; Kaampwe Muzandu; Andrew Kataba; Yoshinori Ikenaka; Hazuki Mizukawa; Russell Dowling; Jack Caravanos; Mayumi Ishizuka
  第26回環境化学討論会, 07 Jun. 2017, English, Oral presentation
  [Domestic Conference]
• ヒト生体試料を用いたネオニコチノイドおよびネオニコチノイド代謝物の分析方法
  一瀬貴大; 池中良徳; 藤岡一俊; 平久美子; 中山翔太; 水川葉月; 八木橋美緒; 有薗幸司; 加藤恵介; 高橋圭介; 石塚真由美
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Poster presentation
  [Domestic Conference]
• Blood Lead Levels in chickens and dogs around lead mining area, Kabwe, Zambia
  Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; John Yabe; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  第26回環境化学討論会, 07 Jun. 2017, English, Oral presentation
  [Domestic Conference]
• イエネコのin vivo長期曝露試験：デカブロモジフェニルエーテル(BDE209)の生体内変化
  田中啓介; 野見山桂; 水川葉月; 口倖暉; 田上瑠美; Aksorn Saengtienchai、Tsend-ayush Sainnoxoi; 横山望; 市居修; 滝口満喜; 中山翔太; 池中良徳; 石塚真由美; 国末達也; 田辺信介
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• PCBs曝露がイヌ・ネコの甲状腺ホルモン恒常性へ及ぼす影響
  ????A???R?j?A?; ?A?; A?c?; ?A?F?; ?A??R; ?A??; A; A; 稍??A?r?; A?; ?R??A??c?; l?A?; B; ?A?c??M?
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• 血清中メタボローム解析によるイエネコのPCBs毒性影響評価
  野見山桂; 西川 博之; 水川葉月; 口倖暉; Tsend-ayush Sainnoxoi; 横山 望; 市居修; 滝口満喜; 石塚真由美; 池中良徳; 中山翔太; 江口哲史; 国末達也; 田辺信介
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• ポリ塩化ビフェニル（PCBs）暴露によるネコ甲状腺機能への影響評価〜甲状腺ホルモンの脱ヨード化と代謝能の解析〜
  水川葉月; 高居名菜; 横山望; 市居修; 滝口満喜; 野見山桂; 高口倖暉; 西川博之; 池中良徳; 中山翔太; Tsend-ayush Sainnoxoi; 田辺信介; 石塚真由美
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• イエネコのin vivo長期曝露試験：デカブロモジフェニルエーテル（BDE209）は甲状腺機能亢進症を引き起こすのか？
  水川葉月; 野見山桂; 池中良徳; 中山翔太; Aksorn Saengtienchai、Tsend-ayush Sainnoxoi; 横山望; 笹岡一慶; 市居修; Kraisiri Khidkhan; 高居名菜; 滝口満喜; 田辺信介; 石塚真由美
  第26回環境化学討論会, 07 Jun. 2017, Japanese, Oral presentation
  [Domestic Conference]
• Comparison of Food Products Contaminated by DDTs in South Africa and Mozambique
  Lesa A. Thompson; Yoshinori Ikenaka; Victor Wepener; Mayumi Ishizuka
  19th International Conference on One Health, 25 May 2017, English, Oral presentation
  [International presentation]
• 代謝酵素の動物種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳
  日本薬学会第137年会シンポジウム, 24 Mar. 2017, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• In situ肝灌流モデルによる殺鼠剤抵抗性野生クマネズミにおけるワルファリン代謝能の解明
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美
  第39回日本分子生物学会年会, 30 Nov. 2016, Japanese, Poster presentation
  [Domestic Conference]
• 化学物質の汚染環境に生きる野生動物の適応戦略
  石塚真由美; 中山翔太; 水川葉月; 池中良徳
  一般社団法人日本環境化学会25周年記念講演会：「環境化学の今、そして未来へ−環境化学からの提言−」, 16 Nov. 2016, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• Monitoring of blood lead levels (BLLs) in dogs and chickens from lead pollution area, Kabwe, Zambia.
  Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; John Yabe; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  International Doctoral Symposium on Sustainable Management of Resources and Environment in the 21st Century, 09 Nov. 2016, English, Poster presentation
  [International presentation]
• Contamination status of organohalogen compounds and their hydroxylated metabolites in pet cats and dogs: effects on thyroid hormones homeostasis.
  Kei Nomiyama; Yasuo Yamamoto; Hazuki Mizukawa; Mitsuyoshi Takiguchi; Akifumi Eguchi; Shouta M.M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Tatsuya. Kunisue; Shinsuke Tanabe
  The 7th SETAC World Congress/37th SETAC North America Annual Meeting, 06 Nov. 2016, English, Poster presentation
  [International presentation]
• Characteristic for biotransformation of polychrolinated biphenyls in cats.
  Hazuki Mizukawa; Misaki Maehara; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Kei Nomiyama; Hiroyuki Nishikawa; Yoshinori Ikenaka; Shouta M.M. Nakayama; Kohki Takaguchi; Shinsuke Tanabe; Mayumi Ishizuka
  The 7th SETAC World Congress/37th SETAC North America Annual Meeting, 06 Nov. 2016, English, Poster presentation
  [International presentation]
• Genetic effects of the pesticide DDT on birds: lessons learned from a field study in South Africa
  Lesa Thompson; Yoshinori Ikenaka; Yared Yohannes; Toshio Tsubota; Johan van Vuren; Victor Wepener; Nico Smit; Shouta Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The 9th International Meeting of the Asian Society of Conservation Medicine (ASCM) "One Health in Asia-Pacific", 21 Oct. 2016, English, Oral presentation
  [International presentation]
• In vivo analysis of PCB metabolic capacities and effects on the thyroid hormone in cats.
  Hazuki, Mizukawa; Misaki Maehara; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Kei Nomiyama; Hiroyuki Nishikawa; Kohki Takaguchi; Aksorn Saengtienchai; Tsend-ayush Sainnoxoi; Yoshinori Ikenaka; Shouta M.M. Nakayama; Shinsuke Tanabe; Mayumi Ishizuka
  The 9th International PCB Workshop, 09 Oct. 2016, English, Oral presentation
  [International presentation]
• 野生げっ歯類の殺鼠剤の抵抗性メカニズムと非対象動物に対する毒性メカニズム
  石塚真由美; 中山翔太; 水川葉月; 池中良徳
  日本哺乳類学会2016年度大会「企画シンポジウム：野生動物が関わる問題にどのように対応するか？〜基礎研究を応用した解決への取り組み〜」, 23 Sep. 2016, Japanese, Oral presentation
  [Domestic Conference]
• Playing "chicken" - a xenobiotic dilemma
  Lesa THOMPSON; Yoshinori IKENAKA; Yared YOHANNES; Atnafu ASSEFA; Johan VAN VUREN; Victor WEPENER; Nico SMIT; Wynand VLOK; Shouta NAKAYAMA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  The 4th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2016, English, Oral presentation
  [International presentation]
• The effect of environmental pollutants to pet animals ~Level and effects of Persistent organic pollutants (POPs) to domestic cat~.
  Tsend-ayush Sainnokhoi; Hazuki Mizukawa; Misaki Maehara; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Kei Nomiyama; Aksorn Saengtienchai; Shinsuke Tanabe; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  The 4th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2016, English, Oral presentation
  [International presentation]
• A glycomics approach to renal biomarkers in birds.
  Chihiro Ishii; Yoshinori Ikenaka; Osamu Ichii; Shouta M.M. Nakayama; Hazuki Mizukawa; Shin-Ichiro Nishimura; Tetsu Ohashi; Masakazu Tanaka; Keisuke Saito; Yukiko Watanabe; Mayumi Ishizuka
  The 4th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2016, English, Oral presentation
  [International presentation]
• Lead exposure on human samples in African countries and lead pollution in Kabwe, Zambia.
  Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; John Yabe; Kaampwe Muzandu; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  The 4th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2016, English, Oral presentation
  [International presentation]
• Investigation of Warfarin Metabolic Ability of Warfarin Resistant Roof Rats by in situ Liver Perfusion.
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  The 4th Sapporo Summer Seminar for One Health (SaSSOH), 20 Sep. 2016, English, Poster presentation
  [International presentation]
• UGT2Bサブファミリーに着目した食肉目におけるグルクロン酸抱合能の動物種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; Aksorn Saengtienchai; Yared Beyene; 坂本健太郎; 和田昭彦; 服部薫; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美
  平成28年度内外環境応答・代謝酵素研究会, 17 Sep. 2016, Japanese, Oral presentation
  [Domestic Conference]
• 鳥類におけるグルクロン酸抱合酵素による薬物代謝
  新屋惣; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 齊藤慶輔; 渡邉有希子; 伊藤真輝; 高江洲昇; 坂本健太郎; 石塚真由美
  第22回日本野生動物医学会, 16 Sep. 2016, Japanese, Oral presentation
  [Domestic Conference]
• 鳥類における新規腎障害マーカーの探索
  石井千尋; 池中良徳; 市居修; 中山翔太; 西村紳一郎; 大橋哲; 田中誠一; 齊藤慶輔; 渡邊有希子; 水川葉月; 石塚真由美
  第22回日本野生動物医学会, 16 Sep. 2016, Japanese, Poster presentation
  [Domestic Conference]
• 家畜・家禽の鉛安定同位体生体内分別の種差および歩哨動物としての有用性評価
  栂尾正雄; 中山翔太; John Yabe; 池中良徳; 中田北斗; 石井千尋; 水川葉月; Yared B. Yohannes; Aksorn Saengtienchai; 石塚真由美
  第159回日本獣医学会学術集会, 06 Sep. 2016, Japanese, Oral presentation
  [Domestic Conference]
• 野生動物及び実験動物におけるグルクロン酸抱合酵素の動物種差解明
  近藤誉充; 池中良徳; 中山翔太; 水川葉月; Aksorn Saengtienchai; Yared Beyene; 坂本健太郎; 和田昭彦; 服部薫; 三谷曜子; 田辺信介; 野見山桂; 石塚真由美
  第159回日本獣医学会学術集会, 06 Sep. 2016, Japanese, Oral presentation
  [Domestic Conference]
• Pharmacokinetic analysis of warfarin resistant roof rats (Rattus rattus) in Tokyo
  Kazuki Takeda; Yoshinori Ikenaka; Tsutomu Tanikawa; Kazuyuki D. Tanaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Poster presentation
  [International presentation]
• Is there species difference of biological variation of lead (Pb) isotopic composition between livestock and poultry?
  Masao Togao; Shouta M.M; Nakayama; John Yabe; Hokuto Nakata; Yoshinori Ikenaka; Chihiro Ishii; Yared B. Yohannes; Hazuki Mizukawa; Wageh Sobhy Darwish; Aksorn Saengtienchai; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Poster presentation
  [International presentation]
• Metabolic capacities of polychlorinated biphenyls (PCBs) in cats and dogs
  Hazuki Mizukawa; Kei Nomiyama; Shinsuke Tanabe; Misaki Maehara; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Poster presentation
  [International presentation]
• Pb levels and isotope ratio profiles in kidneys of Japanese wild rats
  Shouta M.M. Nakayama; Hokuto Nakata; Balazs Oroszlany; Yoshinori Ikenaka; Hazuki Mizukawa; Kazuyuki Tanaka; Tsunehito Harunari; Tsutomu Tanikawa; Yared B. Yohannes; Aksorn Saengtienchai; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Poster presentation
  [International presentation]
• Cytochrome P450 expression in the rabbit
  Walaa Fathy Saad Eldin; Wageh S. Darwish; Yoshinori Ikenaka; Shouta M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Poster presentation
  [International presentation]
• Creating a model of renal damage in chicken and glycomic approach to identify novel biomarkers for kidney injury in birds
  Chihiro Ishii; Yoshinori Ikenaka; Osamu Ichii; Shouta M.M. Nakayama; Shin-Ichiro Nishimura; Tetsu Ohashi; Masakazu Tanaka; Keisuke Saito; Yukiko Watanabe; Hazuki Mizukawa; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Oral presentation
  [International presentation]
• Risk Assessment of Heavy Metals via Consumption of Muscle and Offal of Free-Range Animals from Benin City
  Emmanuel Temiotan; Ogbomida; Shouta M.M. Nakayama; Nesta Bortey-Sam; Balazs Oroszlany; Isioma Tongo; Alex Ajeh Enuneku; Ogbeide Ozekeke; Martins Oshioriamhe Ainerua; Iriagbonse Priscillia Fasipe; Lawrence Ikechukwu Ezemonye; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Oral presentation
  [International presentation]
• Lead exposure on human samples in African countries: a mini review
  Haruya Toyomaki; Shouta M.M. Nakayama; Yared B. Yohannes; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Oral presentation
  [International presentation]
• Kabwe childhood lead poisoning: past, present and future
  John Yabe; Shouta MM Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Haruya Toyomaki; Kennedy Choongo; Kaampwe Muzandu; Mayumi Ishizuka
  8th International Toxicology Symposium in Africa, 29 Aug. 2016, English, Oral presentation
  [International presentation]
• Metal pollution problems in animals and children in Kabwe mining area, Republic of Zambia- Source Estimation by Stable Pb isotopes-
  中山翔太
  第16回北大若手研究者交流会, 19 Aug. 2016, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• 本当にソノポレーションか？
  佐々木東; 工藤信樹; 中山翔太; 滝口満喜
  平成28年度 第2回 光超音波画像研究会, 06 Aug. 2016, Japanese, Oral presentation
  [Domestic Conference]
• N-glycans as potential novel biomarkers for kidney injury in avian species.
  Chihiro Ishii; Yoshinori Ikenaka; Osamu Ichii; Shouta M.M; Nakayama; Hazuki Mizukawa; Shin-Ichiro Nishimura; Tetsu Ohashi; Masakazu Tanaka; Keisuke Saito; Yukiko Watanabe; Mayumi Ishizuka
  65th International Conference of the Wildlife Disease Association,, 31 Jul. 2016, English, Poster presentation
  [International presentation]
• Human health risk due to polycyclic aromatic hydrocarbon (PAHs) exposure in Kumasi, Ghana; and excretion of PAH metabolites in cattle urine from urban and rural sites.
  Nesta Bortey-Sam; Yoshinori Ikenaka; Shouta M.M. Nakayama; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  第30回北海道薬物作用談話会, 31 Jul. 2016, English, Oral presentation
  [Domestic Conference]
• KAMPAI -Team 2, PAST, PRESENT and FUTURE-
  Shouta M.M; Nakayama; John Yabe; Yared Beyene; Haruya Toyomaki; Kaampwe Muzandu; Kennedy Choongo; Hazuki Mizukawa; Yoshinori Ikenaka; Mayumi Ishizuka
  Kick-Off Symposium for the “The Project for Visualization of impact of chronic/latent chemical hazard and Geo-Ecological Remediation in Zambia”, 14 Jul. 2016, English, Oral presentation
  [International presentation]
• UGTの動物種差
  石塚 真由美; 中山 翔太; 水川 葉月; 池中 良徳
  第43回日本毒性学会学術年会, 29 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• ポリ塩化ビフェニル（PCBs）のin vivo暴露によるネコの異物代謝解明と甲状腺ホルモンへの影響評価
  水川 葉月; 前原 美咲; 横山 望; 市居 修; 滝口 満喜; 野見山 桂; 西川 博之; 池中 良徳; 中山 翔太; 高口 倖暉; 田辺 信介; 石塚 真由美
  第43回日本毒性学会学術年会, 29 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• ハリネズミは化学物質高感受性種？ African hedgehog (Atalerix albiventris)で観察された低薬物代謝能
  アクソルン サエンティエンチャイ; 池中 良徳; ネスタ サム; ウスマ ジャムナーク; 水川 葉月; 中山 翔太; 石塚 真由美
  第43回日本毒性学会学術年会, 29 Jun. 2016, Japanese, Poster presentation
  [Domestic Conference]
• 東京由来ワルファリン抵抗性クマネズミクローズドコロニーでのワルファリン体内動態の解明
  武田一貴; 池中良徳; 田中和之; 谷川力; 中山翔太; 水川葉月; 石塚真由美
  第43回日本毒性学会学術年会, 29 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• 脂肪組織における芳香族炭化水素受容体(AhR)の機能解明
  本平 航大; 池中 良徳; ワギ ダルウィシュ; 中山 翔太; 水川 葉月; 石塚 真由美
  第43回日本毒性学会学術年会, 29 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• Contamination of eggs from free-ranging chickens in a malaria-endemic region using DDT as vector control
  Lesa Thompson; Yoshinori Ikenaka; Yared Yohannes; Johan van Vuren; Victor Wepener; Nico Smit; Wynand Vlok; Shouta Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  International Society for Environmental Epidemiology-International Society of Exposure Sciences Asia Chapter (ISEE-ISES AC) 2016, 27 Jun. 2016, English, Oral presentation
  [International presentation]
• メタボローム解析を用いたPCBsによるイエネコの毒性影響評価
  西川博之; 野見山桂; 水川葉月; 横山望; 市居修; 滝口満喜; 石塚真由美; 池中良徳; 中山翔太; 江口哲史; 国末達也; 田辺信介
  第25回環境化学討論会, 08 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• 有機ハロゲン化合物によるコンパニオンアニマルの汚染実態と甲状腺ホルモンへの影響評価
  野見山 桂; 山本 恭央; 水川 葉月; 江口 哲史; 滝口 満喜; 中山 翔太; 池中 良徳; 石塚 真由美; 国末 達也; 田辺 信介
  第25回環境化学討論会, 08 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• ヒト尿中のネオニコチノイドおよびその代謝産物の分析法の確立とヒトへの曝露評価
  池中 良徳; 藤岡 一俊; 平 久美子; 中山 翔太; 水川 葉月; 一瀬 貴大; Jemima Tiwaa Marfo; 有薗 幸司; 加藤 恵介; 石坂 真澄; 馬場 浩司; 川上 智規; 石塚 真由美
  第25回環境化学討論会, 08 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• ネコにおけるポリ塩化ビフェニル（PCBs）の異物代謝機構解明と甲状腺ホルモンへの影響評価
  水川葉月; 前原美咲; 横山望; 市居修; 滝口満喜; 野見山桂; 西川博之; 池中良徳; 中山翔太; 高口倖暉; 田辺信介; 石塚真由美
  第25回環境化学討論会, 08 Jun. 2016, Japanese, Oral presentation
  [Domestic Conference]
• Plasma essential trace element concentrations in dogs with chronic enteropathy.
  Nozomu Yokoyama; Hiroshi Ohta; Hazuki Mizukawa; Yumiko Kagawa; Shouta Nakayama; Noboru Sasaki; Keitaro Morishita; Kensuke Nakamura; Yoshinori Ikenaka; Mayumi Ishizuka; Mitsuyoshi Takiguchi
  American College of Veterinary Internal Medicine Forum 2016, 08 Jun. 2016, English, Oral presentation
  [International presentation]
• Human health risk due to polycyclic aromatic hydrocarbon (PAHs) exposure in Kumasi, Ghana; and excretion of PAH metabolites in cattle urine from urban and rural sites.
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M.M. Nakayama; Kwadwo A. Asante; Christian Obirikorang; Elvis Baidoo; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  SETAC Europe 26th Annual Meeting, 22 May 2016, English, Poster presentation
  [International presentation]
• Risk versus benefits of controlling vector-borne diseases using insecticides: a case example in South Africa
  L A Thompson; Y Ikenaka; Y B Yohannes; J J van Vuren; V Wepener; N J Smit; W Vlok; S M M Nakayama; H Mizukawa; M Ishizuka
  2nd International Conference on One Medicine One Science (iCOMOS), 24 Apr. 2016, English, Poster presentation
  [International presentation]
• 非実験動物における化学物質代謝能の特徴と種差
  池中良徳; 筧麻友; 水川葉月; 中山翔太; 石塚真由美
  日本薬学会第136年会（横浜）, 26 Mar. 2016, Japanese, Oral presentation
  [Domestic Conference]
• TOXICOLOGICAL ASSESSMENT OF PCBS AND OH-PCBS IN CAT USING METABOLOMICS APPROACH
  Hiroyuki Nishikawa; Kei Nomiyama; Akifumi Eguchi; Hazuki Mizukawa; Mayumi Ishizuka; Yoshinori Ikenaka; Shouta M; M. Nakayama; Shinsuke Tanabe
  INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL CHEMISTRY AND TOXICOLOGY ? TO ACCELERATE A GLOBAL NETWORK OF ENVIRONMENTAL RESEARCHERS, 19 Mar. 2016, English, Poster presentation
  [International presentation]
• BIOTRANSFORMATION POTENCIES OF POLYCHLORINATED BIPHENYLS IN CATS
  Hazuki Mizukawa; Misaki Maehara; Nozomu Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Kei Nomiyama; Yoshinori Ikenaka; Shouta M.M.Nakayama; Shinsuke Tanabe; Mayumi Ishizuka
  INTERNATIONAL SYMPOSIUM ON ENVIRONMENTAL CHEMISTRY AND TOXICOLOGY ? TO ACCELERATE A GLOBAL NETWORK OF ENVIRONMENTAL RESEARCHERS, 19 Mar. 2016, English, Poster presentation
  [International presentation]
• 犬の慢性腸症における血中微量元素プロファイルの解析
  横山 望; 大田 寛; 水川 葉月; 賀川 由美子; 中山 翔太; 佐々木 東; 森下 啓太郎; 中村 健介; 池中 良徳; 石塚 真由美; 滝口 満喜
  第12回日本内科学アカデミー学術集会, 19 Feb. 2016, Japanese, Oral presentation
  [Domestic Conference]
• racing migration of northern fur seals in Russian-Japanese waters using stable isotopes in whiskers
  Ayako Yamada; Takanori Horimoto; Yoshinori Ikenaka; Shouta M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka; Yoko Mitani; Kazushi Miyashita
  21st Biennial Conference on Marine Mammals, 13 Dec. 2015, English, Poster presentation
  [International presentation]
• Diet records in winter, migration and diving behavior during early summer of juvenile Steller sea lions in the asian stock
  Keizo Ito; Nao Takahashi; Kaoru Hattori; Yoko Goto; Takuya Nakanowatari; Kay I. Ohshima; Takanori Horimoto; Yoshinori Ikenaka; Shouta M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka; Kazushi Miyashita; Yoko Mitani
  21st Biennial Conference on Marine Mammals, 13 Dec. 2015, English, Poster presentation
  [International presentation]
• The habitat use of northern fur seals Callorhinus ursinus around northern Japan during non-breeding season, defined from stable isotopes and trace elements in whiskers
  Takanori Horimoto; Svetlana Artemyeva; Peter Permyakov; Mari Kobayashi; Kaoru Hattori; Hiromi Kasai; Hiroshige Tanaka; Yoshinori Ikenaka; Shouta M; M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka; Vladimir Burkanov; Russel Andrews; Yoko Mitani; Yasunori Sakurai
  21st Biennial Conference on Marine Mammals, 13 Dec. 2015, English, Poster presentation
  [International presentation]
• Metabolism and biotransformation of organohalogen compounds in the liver microsomes of cats and dogs
  Hazuki Mizukawa; Kei Nomiyama; Nozomu, Yokoyama; Osamu Ichii; Mitsuyoshi Takiguchi; Yoshinori Ikenaka; Shouta M.M; Nakayama; Misaki Maehara; Shinsuke Tanabe; Mayumi Ishizuka
  SETAC North America 36th Annual Meeting, 01 Nov. 2015, English, Poster presentation
  [International presentation]
• Vector-control pesticide DDT detected in free-ranging chickens from South Africa
  Lesa A THOMPSON; Yoshinori IKENAKA; Yared B YOHANNES; Johan J; VAN VUREN; Victor WEPENER; Nico J SMIT; Wynand VLOK; Shouta M M NAKAYAMA; Hazuki MIZUKAWA; Mayumi ISHIZUKA
  The 3rd Sapporo Summer Seminar for One Health (SaSSOH), 16 Sep. 2015, English, Poster presentation
  [International presentation]
• カブエ鉱床地域における鉛汚染とリモートセンシングを活用した今後の研究展望
  中山翔太
  第五回超小型衛星に関する勉強会, 09 Sep. 2015, Japanese, Oral presentation
  [Domestic Conference]
• 抗血液凝固系殺鼠剤の標的分子であるビタミンKエポキシド還元酵素(VKOR)の鳥類における特徴及び種差
  森田鮎子; 池中良徳; 中山翔太; 石井千尋; 水川葉月; 渡邉研右; 齊藤慶輔; 渡邊有希子; 伊藤真輝; 高江洲昇; 石塚真由美
  第158回日本獣医学会学術集会, 07 Sep. 2015, Japanese, Oral presentation
  [Domestic Conference]
• Exposure levels of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in wild rats in Kumasi, Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M.M. Nakayama; Yared Beyene Yohannes; Elvis Baidoo; Aksorn Saengtienchai; Hazuki Mizukawa; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Assessment of exposure to toxic elements (As, Pb, Cd and Hg), and DDTs in four species of birds from Ethiopia
  Yared Beyene Yohannes; Yoshinori Ikenaka; Shouta MM. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• HCH’s in two fish species from a large floodplain pan within a subtropical conservation area
  Clare Edwards; Yoshinori Ikenaka; Yared Beyene; Shouta MM. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka; Victor Wepener, Johan; H.J. van Vuren
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Histopathologic assessment of co-joint Cd and Pb exposure in rats
  ohn Yabe; Yoshinori Ikenaka; Shouta MM Nakayama; Wageh Sobhy Darwish; Nesta Bortey-Sam; Yared B. Yohannes; Aksorn Saengtienchai; Andy Saengtienchai; Takashi Umemura; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Metallothionein as a biomarker for chicken exposure to heavy metals
  Wageh S. Darwish; Walaa F; Saad Eldin; Nesta Bortey-Sam; Yoshinori Ikenaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Lead pollution in the children in Kabwe mining area, Republic of Zambia- Source identification by stable isotope analysis
  Shouta M M; Nakayama; John Yabe; Yoshinori Ikenaka; Yared Beyene Yohannes; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; Hazuki Mizukawa; Kenedy Choongo; Abel Kabalo; Aaron Mweene; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Vector-control pesticide DDT detected in free-ranging chickens from South Africa
  Lesa A Thompson; Yoshinori Ikenaka; Yared B Yohannes; Johan van Vuren; Victor Wepener; Nico J Smit; Wynand Vlok; Shouta M M Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  7th International Toxicology Symposium in Africa, 31 Aug. 2015, English, Oral presentation
  [International presentation]
• Accumulation Patterns and Risk Assessment of Metals and Metalloids in Muscle and Offal of free Range Chickens (Gallus gallus domesticus), Cattle (Bos taurus) and Goat (Capra hircus) in Benin City
  Ogbomida, E.T; Nakayama S.M.M; Bortey-Sam N; Oroszlany, B; Tongo I; Enuneku A.A; Ogbeide O; Oshioriamhe M.A; Fasipe, P.I; Ezemonye L.I.N; Mizukawa H; Ikenaka Y; Ishizuka M
  7th SETAC Africa Conference, 05 Aug. 2015, English, Oral presentation
  [International presentation]
• Phase II xenobiotic metabolizm in carnivora -UGT activity and genomestructure in Pinniped species-
  Yoshinori Ikenaka; Mayu Kakehi; Shouta Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  7th SETAC Africa Conference, 05 Aug. 2015, English, Oral presentation
  [International presentation]
• シンポジウム「野生鳥類の化学物質汚染とその影響」鳥類で起こっているケミカルハザードとそのメカニズム
  中山翔太; 水川葉月; 池中良徳; 石塚真由美
  第21回日本野生動物医学会大会, 30 Jul. 2015, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• 北海道沿岸にストランディングした鯨類の臓器における金属濃度の測定とその比較検討
  川田大紀; 松田純佳; 松石隆; 中山翔太; 石塚真由美; 浅川満彦; 能田淳
  第21回日本野生動物医学会大会, 30 Jul. 2015, Japanese, Poster presentation
  [Domestic Conference]
• Protective Effects of Carotenoids and Retinoids on Benzo[a]Pyrene Induced Mutagenicity and Oxidative Stress
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta M.M; Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  42nd Annual Meeting of the Japanese Society of Toxicology (42JSOT), 29 Jun. 2015, English, Oral presentation
  [Domestic Conference]
• Vector-control pesticides disseminating via international waterways to accumulate in free-ranging freshwater and marine fish species
  Lesa A Thompson; Yoshinori Ikenaka; Johannes J; van Vuren; Victor, Wepener; Nico Smit; Wynand Vlok; Yared B. Yohannes; Hazuki Mizukawa; Shouta M.M. Nakayama; Mayumi Ishizuka
  Vth International Wildlife Management Congress 2015, 26 Jun. 2015, English, Poster presentation
  [International presentation]
• Lead poisoning and source identification in raptors from Japan
  Chihiro Ishii; Shouta M.M. Nakayama; Yoshinori Ikenaka; Hazuki Mizukawa; Yared B. Yohannes; Hokuto Nakata; Keisuke Saito; Yukiko Watanabe; Shinsuke Tanabe; Kei Nomiyama; Terutake Hayashi; Yasushi Masuda; Kentaro; Q. Sakamoto; Mayumi Ishizuka
  Vth International Wildlife Management Congress 2015, 26 Jun. 2015, English, Oral presentation
  [International presentation]
• 渡り性海鳥2種の越冬海域と羽の水銀濃度
  綿貫豊; 山下愛; 石塚真由美; 池中良徳; 中山翔太; 石井千尋; 山本誉士; 伊藤元裕; 桑江 朝比呂; 鈴木裕也; 新妻靖彰; C.E. Meathrel; P.N. Trathan; R.A. Phillips
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Poster presentation
  [Domestic Conference]
• タンチョウの水銀蓄積特性に関する検討
  寺岡宏樹; 岡本絵梨佳; 久道萌; 中山翔太; 池中良徳; 石塚真由美; 北澤多喜雄
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Poster presentation
  [Domestic Conference]
• ウマにおけるシトクロムP450の特性評価：ジアゼパム代謝を担うCYP3Aの重要性
  水川葉月; 中山翔太; 池中良徳; 速水秋; Wageh Sobhy Darwish; 渡邊研右; 川合佑典; 石塚真由美
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Poster presentation
  [Domestic Conference]
• 第II相抱合反応の種差：食肉目におけるグルクロン酸抱合酵素の進化と遺伝子構造
  池中良徳; 筧麻友; 中山翔太; 川合佑典; 渡邊研右; 水川葉月; 野見山桂; 田辺信介; 石塚真由美
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Oral presentation
  [Domestic Conference]
• Vector-controlling pesticides in free-ranging chickens in KwaZulu-Natal, South Africa
  Lesa A Thompson; Yoshinori Ikenaka; Johannes J; van Vuren; Victor, Wepener; Nico Smit; Wynand Vlok; Yared B Yohannes; Hazuki Mizukawa; Shouta M; M. Nakayama; Mayumi Ishizuka
  第24回環境化学討論会, 24 Jun. 2015, English, Oral presentation
  [Domestic Conference]
• Victor Wepener, Insights into sub-tropical lowland river food webs using stable isotopes
  Ruan Gerber; Nico J. Smit, Johan; H.J. Van Vuren; Shouta M.M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Victor Wepener
  第24回環境化学討論会, 24 Jun. 2015, English, Oral presentation
  [Domestic Conference]
• Nitrate content in Egyptian meat products and its modulatory effects on xenobiotic metabolizing enzymes
  Wageh Sobhy Darwish; Mohamed Abdallah Hussein; Yoshinori Ikenaka; Shouta M.M; Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  第24回環境化学討論会, 24 Jun. 2015, English, Oral presentation
  [Domestic Conference]
• Concentrations of polycyclic aromatic hydrocarbon metabolites (OH-PAHs) in domestic animal in Kumasi, Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Osei Akoto; Shouta M.M. Nakayama; Jemima Marfo; Hazuki Mizukawa; Mayumi Ishizuka
  第24回環境化学討論会, 24 Jun. 2015, English, Oral presentation
  [Domestic Conference]
• 野生齧歯類におけるワルファリン抵抗性獲得機序の解明
  武田一貴; 池中良徳; 田中和之; 中山翔太; 谷川力; 水川葉月; 石塚真由美
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Oral presentation
  [Domestic Conference]
• 猛禽類における鉛中毒問題と骨における鉛分布の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中田北斗; 森田鮎子; 齊藤慶輔; 渡邊有希子; 神和夫; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美
  第24回環境化学討論会, 24 Jun. 2015, Japanese, Oral presentation
  [Domestic Conference]
• Lead (Pb) poisoning in children from townships around an extensive lead-zinc mine in Kabwe, the Republic of Zambia
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Yared Beyene; Nesta Bortey-Sam; Balazs Oroszlany; Kaampwe Muzandu; Kennedy Choongo; Aaron Mweene; Abel Kabalo; Hazuki Mizukawa; Mayumi Ishizuka
  日本地球惑星科学連合2015年大会, 24 May 2015, Japanese, Oral presentation
  [Domestic Conference]
• 日本海北部に来遊するキタオットセイ の安定同位体比と利用海域の関係
  山田綾子; 堀本高矩; 石塚真由美; 池中良徳; 中山翔太; 水川葉月; 三谷曜子; 宮下和士
  平成27年度日本水産学会秋季大会, 27 Mar. 2015, Japanese, Oral presentation
  [Domestic Conference]
• High concentration of Pb in soil, domestic animals and children from townships near a lead-zinc mine in Kabwe
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Mayumi Ishizuka
  Workshop on Mining and the Environment, 13 Mar. 2015, English, Invited oral presentation
  [Invited], [International presentation]
• 外来化学物質の代謝の種差
  石塚真由美; 中山翔太; 水川葉月; 池中良徳
  第31回日本毒性病理学シンポジウム「毒性病理学と獣医病理学を繋ぐ比較の生物学−共通性と種差を知ろう」, 29 Jan. 2015, Japanese, Invited oral presentation
  [Invited], [Domestic Conference]
• 食肉目におけるグルクロン酸抱合酵素の遺伝子解析
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邉研右; 坂本健太郎; 和田 昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美
  第37回日本分子生物学会年会, 25 Nov. 2014, Japanese, Poster presentation
  [Domestic Conference]
• Distribution of toxic metals in free-range chicken, goat and sheep in Ghana and other African countries; and assessment of potential risks to human health through consumption
  Nesta Bortey-Sam; Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared Beyene Yohannes; Elvis Baidoo; Hazuki Mizukawa; Osei Akoto; Mayumi Ishizuka
  SETAC North America 35th Annual Meeting, 09 Nov. 2014, English, Poster presentation
  [International presentation]
• Species differences of UDP-glucuronosyltransferases (UGTs) in Carnivores
  Mayu Kakehi; Yoshinori Ikenaka; Shouta MM Nakayama; Hazuki Mizukawa; Kensuke P; Watanabe; Kentaro Sakamoto; Akihiko Wada; Kaoru Hattori; Shinsuke Tanabe; Kei Nomiyama; Mayumi Ishizuka
  12th International Symposium on Cytochrome P450 Biodiversity and Biotechnology, 24 Sep. 2014, English, Poster presentation
  [International presentation]
• Mammalian interspecies differences in xenobiotic phase II reaction
  Yoshinori Ikenaka; Saengtienchai Aksorn; Mayu Kakehi; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka
  12th International Symposium on Cytochrome P450 Biodiversity and Biotechnology, 24 Sep. 2014, English, Invited oral presentation
  [Invited], [International presentation]
• Contamination status and biotransformation of organohalogen compounds in cats and dogs
  Hazuki Mizukawa; Kei Nomiyama; Susumu Nakatsu; Akira Kubota; Hisato Iwata; Yoshinori Ikenaka; Shouta M.M. Nakayama; Shinsuke Tanabe; Mayumi Ishizuka
  12th International Symposium on Cytochrome P450 Biodiversity and Biotechnology, 24 Sep. 2014, English, Poster presentation
  [International presentation]
• 鰭脚類においてグルクロン酸抱合酵素が担う異物代謝
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邉研右; 坂本健太郎; 和田 昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美
  第20回日本野生動物医学会つくば大会, 16 Sep. 2014, Japanese, Poster presentation
  [Domestic Conference]
• ニワトリにおけるDDTの汚染状況と臓器蓄積性の解析
  伊藤玄悟; 池中良徳; Beyene Yared; 中山翔太; 水川葉月; Vuren Johannes; Wepener Victor; Smit Nico; ynand Vlok; 石塚真由美
  第157回日本獣医学会学術集会, 09 Sep. 2014, Japanese, Oral presentation
  [Domestic Conference]
• 日本における猛禽類の鉛中毒被害状況と中毒原因、鉛体内分布の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中田北斗; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美
  第157回日本獣医学会学術集会, 09 Sep. 2014, Japanese, Oral presentation
  [Domestic Conference]
• アフリカのゴミ集積場における化学物質の汚染実態と生体への健康影響の評価：ナイロビのダンドラ地域における家畜の重金属汚染の例
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; ヨハンネス ヤレド; ベイヤネ; ヤベジョン; 今内覚; 石塚真由美
  第157回日本獣医学会学術集会, 09 Sep. 2014, Japanese, Oral presentation
  [Domestic Conference]
• The impact of environmental stressors on biomarkers in Clarias gariepinus and Oreochromis mossambicus in Ndumo game reserve
  Mary Tsono Mkhonto; Johan J; van Vuren; Nico Smit; Yoshinori Ikenaka; Shouta M.M. Nakayama; Hazuki Mizukawa; Yared Beyene Yohannes; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Antibiotics residues in different poultry meats marketed in Egypt
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta Nakayama; Mayumi Ishizuka; Eldaly Elsaid; El-Abbasy Mohamed; El-Ghareeb Walid; Tharwat Ahmed; El-Desoky Kamal; Elged Mohamed
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Biomarkers of pollution in Synodontis zambesensis and Hydrocynus vittatus in the lower Pongola river and floodplain
  Claire Michelle Edwards; Yoshinori Ikenaka; Yared Beyene Yohannes; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi Ishizuka; Victor Wepener; Johan J; van Vuren
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Aquatic toxicology of gold nanoparticles (nAu) in Danio rerio
  Tarryn Lee Botha; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka; Victor Wepener
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Comparison of the Olifants and Luvuvhu river aquatic food webs, potential food web disturbances and dietary patterns of Hydrocynus vittatus as revealed by stable isotope analyses
  Ruan Gerber; Victor Wepener; Johan J; van Vuren; Shouta M.M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka; Nico Smit
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Distribution of heavy metals in organs of sheep and goat reared in Obuasi, a gold mining town in Ghana
  Osei Akoto; Nesta Bortey-Sam; Shouta M.M. Nakayama; Yoshinori Ikenaka; Elvis Baidoo; Yared Beyene Yohannes; Hazuki Mizukawa; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Health Risk Assessment of Heavy Metal Residues in Tissues of Cattle and Goats in Benin City, Nigeria
  Emmanuel Temiotan; Ogbomida; Isioma Tongo; Alex Ajeh Enuneku; Martins Oshioriamhe Ainerua; Shouta M.M. Nakayama; Nesta Bortey-Sam; Balazs Oroszlany; Lawrence Ikechukwu Ezemonye; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Pb excretion in feces and urine of exposed children from polluted townships in Kabwe, Zambia
  John Yabe; Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared B Yohannes; Nesta Bortey-Sam; Balazs Oroszlany; Kaampwe Muzandu; Kennedy Choongo; Abel Nketani Kabalo; John Ntapisha; Aaron Mweene; Takashi Umemura; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Effects of international land-based use of vector-control pesticides on a marine ecosystem: organochlorine analysis of fish from Maputo Bay, Mozambique
  Lesa Thompson; Yoshinori Ikenaka; Yared Beyene Yohannes; Shouta M.M. Nakayama; Hazuki Mizukawa; Johannes J; van Vuren; Victor Wepener; Nico J. Smit; Volk Wynand; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Human and ecological health risk assessment of pesticides used for vector control: Current situation and problems of DDT use in Africa
  Yoshinori Ikenaka; Yared Beyene Yohannes; Lesa Thompson; Shouta M.M. Nakayama; Hazuki Mizukawa; Johannes J; van Vuren; Victor Wepener; Nico J. Smit; Volk Wynand; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Contamination status of organohalogen compounds and their metabolites in the blood of pet dogs and cats
  Hazuki Mizukawa; Kei Nomiyama; Miyuki Yamamoto; Yoshinori Ikenaka; Shouta M.M. Nakayama; Shinsuke Tanabe; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Oral presentation
  [International presentation]
• Investigation of heavy metal contamination and assessment of impact on health in Dandora dumping site, Nairobi
  Hokuto Nakata; Shouta M.M. Nakayama; Hazuki Mizukawa; Yoshinori Ikenaka; Chihiro Ishii; Yared Beyene Yohannes; John Yabe; Satoru Konnai; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Poster presentation
  [International presentation]
• Preliminary survey of lead poisoning in raptors from Japan
  Chihiro Ishii; Shouta M.M. Nakayama; Yoshinori Ikenaka; Hazuki Mizukawa; Yared B. Yohannes; Hokuto Nakata; Keisuke Saito; Yukiko Watanabe; Shinsuke Tanabe; Kei Nomiyama; Terutake Hayashi; Yasushi Masuda; Kentaro; Q. Sakamoto; Mayumi Ishizuka
  6th International Toxicology Symposium in Africa, 29 Aug. 2014, English, Poster presentation
  [International presentation]
• 食肉目におけるグルクロン酸抱合酵素の解析および種差
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邉研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美
  第28回北海道薬物作用談話会, 19 Jul. 2014, Japanese, Oral presentation
  [Domestic Conference]
• ペット動物における有機ハロゲン化合物の汚染実態解明と水酸化代謝物の動態解析
  水川葉月; 野見山桂; 中津賞; 池中良徳; 中山翔太; 田辺信介; 石塚真由美
  第28回北海道薬物作用談話会, 19 Jul. 2014, Japanese, Oral presentation
  [Domestic Conference]
• 鰭脚類におけるグルクロン酸抱合酵素の解析
  筧麻友; 池中良徳; 中山翔太; 水川葉月; 渡邊研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美
  第41回日本毒性学会学術年会, 02 Jul. 2014, Japanese, Oral presentation
  [Domestic Conference]
• 鰭脚類を中心とした食肉目において異物代謝を担うグルクロン酸抱合酵素の特徴
  筧麻友; 中山翔太; 水川葉月; 池中良徳; 渡邊研右; 坂本健太郎; 和田昭彦; 服部薫; 田辺信介; 野見山桂; 石塚真由美
  第41回日本毒性学会学術年会, 02 Jul. 2014, Japanese, Poster presentation
  [Domestic Conference]
• ケニアの大規模ゴミ集積場・ダンドラ地域における家畜の化学物質汚染の実態と住民の健康影響評価
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; ヨハンネス ヤレド ベイヤネ; 今内覚; 石塚真由美
  第41回日本毒性学会学術年会, 02 Jul. 2014, Japanese, Oral presentation
  [Domestic Conference]
• 日本に生息する猛禽類の鉛汚染状況と鉛安定同位体比を指標とした汚染源の解明
  石井千尋; 中山翔太; 池中良徳; 水川葉月; 中田北斗; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美
  第41回日本毒性学会学術年会, 02 Jul. 2014, Japanese, Oral presentation
  [Domestic Conference]
• Health risk assessment of atmospheric polycyclic aromatic hydrocarbons in Kumasi-Ghana
  Nesta Bortey-Sam; Yoshinori Ikenaka; Shouta M.M. Nakayama; Osei Akoto; Yared Beyene Yohannes; Hazuki Mizukawa; Mayumi Ishizuka
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• Lead pollution in the children in Kabwe mining area, Republic of Zambia
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Yared Beyene; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; Kennedy Choongo; Abel Kabalo; John Ntapisha; Aaron Mweene; Takashi Umemura; Mayumi Ishizuka
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• Mohamed Tharwat El-Abbasy, Mayumi Ishizuka, Residue levels and health risk assessment of organochlorine pesticides (OCPs) in domesticated animals from Egypt
  Abdallah Fikry; A. Mahmoud; Elsaid A. Eldaly; Alaa Eldin; M.A. Morshdy; Yoshinori Ikenaka; Shouta Nakayama; Hazuki Mizukawa; Yared B. Yohannes; Waleed R. El-Ghareeb
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• Quantification of Neonicotinoids in human urine using liquid chromatography/tandem mass spectrometry
  Jemima Tiwaa Marfo; Yoshinori Ikenaka; Shouta M; M. Nakayama; Hazuki Mizukawa; Kumiko Taira; Kazutoshi Fujioka; Yoshiko Aoyama; Osei Akoto; Mayumi Ishizuka
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• 日本に生息する猛禽類における鉛汚染状況の解析、第23回環境化学討論会
  石井千尋; 池中良徳; 中山翔太; 水川葉月; 齊藤慶輔; 渡邊有希子; 田辺信介; 野見山桂; 林光武; 増田泰; 坂本健太郎; 石塚真由美
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• アフリカのゴミ集積場における化学物質の汚染実態と生体への健康影響の評価：ナイロビのダンドラ地域における重金属汚染の例
  中田北斗; 中山翔太; 水川葉月; 池中良徳; 石井千尋; ヨハンネス ヤレド ベイヤネ; 今内覚; 石塚真由美
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• ネコ科動物における有機ハロゲン化合物の代謝能解析
  水川葉月; 池中良徳; 野見山桂; 田辺信介; 宇根有美; 伊藤真輝; 高江洲昇; 長野靖子; 中山翔太; 石塚真由美
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• ベクターコントロールのための薬剤散布の生態系およびヒト健康に与える影響評価
  池中良徳; Yared Yohannes; 中山翔太; 水川葉月; van Vuren Johannes; Wepener Victor; Smit Nico; ynand Vlok; 石塚真由美
  第23回環境化学討論会, 14 May 2014, Japanese, Oral presentation
  [Domestic Conference]
• Pb and Cd contaminated soil may cause metal accumulation and epigenetic alteration in rat tissues
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; John Yabe; Takashi Umemura; Mayumi Ishizuka
  SOT 53rd Annual Meeting, 23 Mar. 2014, English, Oral presentation
  [International presentation]
• Lead pollution in soil, domestic animals and children from townships near a lead-zinc mine in Kabwe, Zambia
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Yared B. Yohannes; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; Kennedy Choongo; Abel Nketani Kabalo; John Ntapisha; Aaron Mweene; Takashi Umemura; Mayumi Ishizuka
  SOT 53rd Annual Meeting, 23 Mar. 2014, English, Oral presentation
  [International presentation]
• Pb and Cd contaminated soil may cause metal accumulation and epigenetic alteration in laboratory rat and wild black rat
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; John Yabe; Takashi Umemura; Mayumi Ishizuka
  SETAC North America 34th Annual Meeting, 17 Nov. 2013, English, Oral presentation
  [International presentation]
• Accumulation characteristics of arsenic and metals in environmental samples and wild black rat (Rattus rattus) in gold mining area, Obuasi, Ghana
  Shouta M.M. Nakayama; Go Otani; Yoshinori Ikenaka; Yared B Yohannes; Osei Akoto; Joseph Apau; Elvis Baidoo; Mayumi Ishizuka
  SETAC North America 34th Annual Meeting, 17 Nov. 2013, English, Oral presentation
  [International presentation]
• Lead poisoning in children from townships around a lead-zinc mine in Kabwe, Zambia
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Kaampwe Muzandu; John Ntapisha; Aaron Mweene; Abel Kabalo; Takashi Umemura; Mayumi Ishizuka
  SETAC North America 34th Annual Meeting, 17 Nov. 2013, English, Oral presentation
  [International presentation]
• Accumulation features of organochlorine pesticides in resident birds and their prey from Ethiopian Rift Valley Region
  Yared B. Yohannes; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  SETAC North America 34th Annual Meeting, 17 Nov. 2013, English, Oral presentation
  [International presentation]
• Species difference of warfarin sensitivity among birds can be explained by the two enzymes, cytochrome P450 and vitamin K epoxide reductase
  Kensuke P; Watanabe; Yusuke K. Kawai; Minami Kawata; Shouta M.M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka
  10th International ISSX (International Society for the Study of Xenobiotics) Meeting, 29 Oct. 2013, English, Oral presentation
  [International presentation]
• In vitroにおけるウマのジアゼパム代謝
  速水秋; Wageh Sobhy Darwish; 池中良徳; 中山翔太; 石塚真由美
  第156回日本獣医学会学術集会, 20 Sep. 2013, Japanese, Oral presentation
  [Domestic Conference]
• Accumulation of metals and metalloid in organs of rats, sheep and goats from Dunkwa-on-Offin, Ghana
  emima T. Marfo; Osei Akoto; Elvis Baidoo; Shouta M; M. Nakayama; Yoshinori Ikenaka; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Distribution of toxic metals in organs of free range chicken, goat and sheep near gold mines in Tarkwa, Ghana
  Nesta Bortey-Sam; Osei Akoto; Yoshinori Ikenaka; Shouta M.M. Nakayama; Elvis Baidoo; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• The characteristics and mechanism of pyrene metabolism in freshwater turtles and the suggested genetic background
  Balazs Oroszlany; Yoshinori Ikenaka; Aksorn Saengtienchai; Mami Oguri; Shouta M.M. Nakayama; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Lead poisoning in children from townships in the vicinity of a lead-zinc mine in Kabwe, Zambia
  John Yabe; Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Balazs Oroszlany; Nesta Bortey-Sam; Kaampwe Muzandu; Kennedy Choongo; Abel Nketani Kabalo; John Ntapisha; Aaron Mweene; Takashi Umemura; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Lead and cadmium pollution in soil and edible tissues of cattle and chickens from townships near a lead-zinc mine in Kabwe, Zambia
  Shouta M.M; Nakayama; John Yabe; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Takashi Umemura; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Assessment of heavy metals into rivers of Katanga, DR Congo
  John Ngoy Kalenga; Tetsuhiko Takai; Yoshinori Ikenaka; Shouta Nakayama; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• OCPs in fish species from Lake Ziway, Ethiopia: Association with trophic level and human health risk assessment
  Yared B. Yohannes; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Characterization and interspecies diversity of xenobiotic metabolism: a study of phase-II conjugation reactions
  Yoshinori Ikenaka; Aksorn Saengtienchai; Shouta M.M. Nakayama; Hazuki Mizukawa; Mayumi ISHIZUKA
  5th International Toxicology Symposium in Africa, 12 Sep. 2013, English, Oral presentation
  [International presentation]
• Lead poisoning in children from townships in the vicinity of a lead-zinc mine in Kabwe, Zambia
  ohn Yabe; Shouta M.M. Nakayama; Yoshinori Ikenaka; Yared B. Yohannes; Nesta Bortey-Sam; Balazs Oroszlany; Kaampwe Muzandu; Kennedy Choongo; John Ntapisha; Aaron Mweene; Abel Kabalo; Koji Arizono; Takashi Umemura; Mayumi Ishizuka
  6th SETAC Africa Conference, 02 Sep. 2013, English, Oral presentation
  [International presentation]
• OCPs profiles in Birds and Their Prey from Ethiopian Rift Valley Region
  Yared B. Yohannes; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  6th SETAC Africa Conference, 02 Sep. 2013, English, Oral presentation
  [International presentation]
• ガーナの金鉱山周辺（オブアシ自治区）におけるヒ素汚染と陸生哺乳類への毒性影響評価
  大谷豪; 池中良徳; 中山翔太; Osei Akoto; Joseph Apau; Elvis Baidoo; 石塚真由美
  第22回環境化学討論会, 31 Jul. 2013, Japanese, Oral presentation
  [Domestic Conference]
• 鳥類における金属の汚染状況と蓄積特性の解析
  石井千尋; 池中良徳; 中山翔太; 鈴木優也; 綿貫豊; 渡邊雄児; 福若雅章; Yared Yohannes; 川合佑典; 石塚真由美
  第22回環境化学討論会, 31 Jul. 2013, Japanese, Oral presentation
  [Domestic Conference]
• 野生げっ歯類におけるワルファリン抵抗性機構
  池中良徳; 田中和之; 中山翔太; 春成常仁; 谷川力; 水川葉月; 石塚真由美
  第22回環境化学討論会, 31 Jul. 2013, Japanese, Oral presentation
  [Domestic Conference]
• Effects of Pb and Cd contaminated soil on metal accumulation and epigenetic alteration in rat
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; John Yabe; Takashi Umemura; Mayumi Ishizuka
  第22回環境化学討論会, 31 Jul. 2013, English, Oral presentation
  [Domestic Conference]
• OCPs in Fish and Bird Species from a DDT Spraying and Agriculture Area in Ethiopia
  Yared B. Yohannes; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  22nd Symposium on Environmental Chemistry, 31 Jul. 2013, English, Oral presentation
  [International presentation]
• Incidence of Metals and Polycyclic Aromatic Hydrocarbons (PAHs) in Surface Soils from the Kumasi Metropolis, Ghana- GIS Based Approach
  Nesta Bortey-Sam; Osei Akoto; Yoshinori Ikenaka; Elvis Baidoo; Beyene Yared; Shouta M.M. Nakayama; Mayumi Ishizuka
  22nd Symposium on Environmental Chemistry, 31 Jul. 2013, English, Oral presentation
  [International presentation]
• The study of xenobiotic metabolism phase II reactions in pigs:sulfotransferase enzymatic efficiency observed by in vitro kinetic analysis
  Aksorn Saengtienchai; Yoshinori Ikenaka; Wageh Sobhy Darwish; Yusuke K. Kawai; Shouta M.M. Nakayama; Shigeo Ito; Mayumi Ishizuka
  International Congress of Toxicology 2013, 30 Jun. 2013, English, Oral presentation
  [International presentation]
• Regulatory effects of carotenoids on Aryl hydrocarbon receptor (AhR) gene battery
  Wageh Sobhy Darwish; Yoshinori Ikenaka; Shouta Nakayama; Mayumi Ishizuka
  The 40th Annual Meeting of the Japanese Society of Toxicology, 17 Jun. 2013, English, Oral presentation
  [Domestic Conference]
• Pyrene metabolism and the role of phase I and phase II enzymes in freshwater turtles,
  Balazs Oroszlany; Yoshinori Ikenaka; Aksorn Saengtienchai; Mami Oguri; Shouta M.M. Nakayama; Mayumi Iishizuka
  The 40th Annual Meeting of the Japanese Society of Toxicology, 17 Jun. 2013, English, Oral presentation
  [Domestic Conference]
• Characteristics of phase II metabolism reaction in pig: Clear sulfation and sulfotransferase activity observed in pyrene
  Aksorn Saengtienchai; Yoshinori Ikenaka; Shouta M.M. Nakayama; Yusuke Kawai; Mayumi Ishizuka
  第155回 日本獣医学会学術集会, 30 Mar. 2013, English, Oral presentation
  [Domestic Conference]
• 海鳥における金属の汚染状況と蓄積特性の解析
  石井千尋; 池中良徳; 中山翔太; 鈴木優也; 綿貫豊; 渡邊雄児; 福若雅章; Yared Yohannes; 川合佑典; 石塚真由美
  第155回 日本獣医学会学術集会, 30 Mar. 2013, Japanese, Oral presentation
  [Domestic Conference]
• Bioaccumulation levels of organochlorine pesticides in fish species from Ethiopian Rift Valley Lake Ziway, Ethiopia
  Yared B. Yohannes; Yoshinori Ikenaka; Shouta M.M. Nakayama; Aksorn Saengtienchai; Kensuke Watanabe; Mayumi Ishizuka
  SETAC Asia/Pacific Annual Meeting 2012, 25 Sep. 2012, English, Oral presentation
  [International presentation]
• Metal contaminated soil from mining area caused accumulation and biological responses in rats −from field and laboratory studies−
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Takashi Umemura; Mayumi Ishizuka
  SETAC Asia/Pacific Annual Meeting 2012, 25 Sep. 2012, English, Oral presentation
  [International presentation]
• In vitro diazepam metabolism in horses
  Aki Hayami; Wageh Sobhy DARWISH; Yoshinori Ikenaka; Shouta M.M. Nakayama; Mayumi Ishizuka
  4th International Toxicology Symposium in Africa, 03 Sep. 2012, English, Oral presentation
  [International presentation]
• Heavy metal pollution in sea birds
  Chihiro Ishii; Yoshinori Ikenaka; Shouta M.M. Nakayama; Yuya Suzuki; Yutaka Watanuki; Yuji Watanabe; Masa-aki Fukuwaka; John Yabe; Yared B. Yohannes; Yusuke K. Kawai; Mayumi Ishizuka
  4th International Toxicology Symposium in Africa, 03 Sep. 2012, English, Oral presentation
  [International presentation]
• Metabolism of pyrene, a polycyclic aromatic hydrocarbon in freshwater turtles
  Balazs Oroszlany; Yoshinori Ikenaka; Aksorn Saengtiengchan; Mami Oguri; Shouta M.M. Nakayama; Mayumi Ishizuka
  4th International Toxicology Symposium in Africa, 03 Sep. 2012, English, Oral presentation
  [International presentation]
• Metal contaminated soil from mining area caused metal accumulation and biological responses in rats −from field and laboratory studies−
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Takashi Umemura; Mayumi Ishizuka
  4th International Toxicology Symposium in Africa, 03 Sep. 2012, English, Oral presentation
  [International presentation]
• Levels and Bioaccumulation of Organochlorine Pesticides in Fish Species from Lake Ziway, ETHIOPIA
  Yared B. Yohannes; Yoshinori IKENAKA; Kensuke WATANABE; Aksorn SAENGTIENCHAI; Shouta NAKAYAMA; Mayumi ISHIZUKA
  21th symposium on Environmental Chemistry, 11 Jul. 2012, English, Oral presentation
  [International presentation]
• GIS based source estimation of Cu pollution in Lake Itezhi-tezhi and Cu accumulation profile in Oreochromis sp. from the field and laboratory studies
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Taro Muroya; Shigeho Ijiri; Takashi Umemura; Mayumi Ishizuka
  SETAC North America 32nd Annual Meeting, 15 Nov. 2011, English, Oral presentation
  [International presentation]
• アカハライモリとアフリカツメガエルにおける異物代謝酵素の比較
  上田春樹; 中山翔太; 川合佑典; 田中-上野寛子; 池中良徳; 石塚真由美
  日本爬虫両棲類学会 第50回大会, 08 Oct. 2011, Japanese, Oral presentation
  [Domestic Conference]
• ラットにおける薬物代謝酵素シトクロムP450の系統差について
  西山義広; 池中良徳; 大野円実; 渡邉研右; 川合佑典; 中山翔太; 田中和之; 石塚真由美
  第152回日本獣医学会学術集会, 21 Sep. 2011, Japanese, Oral presentation
  [Domestic Conference]
• ラットの消化管における異物代謝酵素の比較
  糸谷悠美; 池中良徳; 大野円実; 中山翔太; ワギ ソベイ; 石塚真由美
  第152回日本獣医学会学術集会, 21 Sep. 2011, Japanese, Oral presentation
  [Domestic Conference]
• GIS-based source estimation of Cu pollution in Lake Itezhi-tezhi and metal accumulation profiles in Oreochromis sp. and other fish species from both and laboratory studies
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Taro Muroya; Shigeho Ijiri; Takashi Umemura; Mayumi Ishizuka
  3rd International Toxicology Symposium in Africa, 08 Sep. 2011, English, Oral presentation
  [International presentation]
• Effects of current malaria control in lake environment; The levels of Organochlorine pesticide and toxic metals in fish species from Lake Awassa, Ethiopia
  Yoshinori IKENAKA; Yared Beyene; Kensuke WATANABE; Aksorn Saengtienchai; Shouta NAKAYAMA; Mayumi ISHIZUKA
  3rd International Toxicology Symposium in Africa, 08 Sep. 2011, English, Oral presentation
  [International presentation]
• ガーナの金鉱山周辺（オブアシ自治区）における金属汚染と野生ラットにおける毒性影響評価
  大谷豪; 池中良徳; 中山翔太; Osei Akoto; Joseph APAU; Elvis BAIDOO; 石塚真由美
  第20回環境化学討論会, 17 Jul. 2011, Japanese, Oral presentation
  [Domestic Conference]
• Effects of current malaria control in lake environment; The levels of Organochlorine pesticide and toxic metals in fish species from Lake Awassa, ETHIOPIA
  YARED Beyene; Yoshinori IKENAKA; Kensuke WATANABE; Aksorn SAENGTIENCHAI; Shouta NAKAYAMA; Mayumi ISHIZUKA
  第20回環境化学討論会, 17 Jul. 2011, English, Oral presentation
  [Domestic Conference]
• Metal and metalloid levels and bio-accumulation characteristics in soil, sediment, land plants and hippopotami (Hippopotamus amphibius L) from the South Luangwa National Park, Zambia
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Ethel M’kandawire; Jun Yasuda; Mayumi Ishizuka
  第20回環境化学討論会, 17 Jul. 2011, English, Oral presentation
  [Domestic Conference]
• Metal concentration and stable isotope ratio analysis (d13C and d15N) in water, sediment and fish from Lake Itezhi-tezhi, Zambia
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; John Yabe; Taro Muroya; Takashi Umemura; Mayumi Ishizuka
  第20回環境化学討論会, 17 Jul. 2011, English, Oral presentation
  [Domestic Conference]
• Concentration and bioaccumulation of 10 metals in soil, river sediment, plant and hippopotamus (Hippopotamus amphibius L) in the South Luangwa National Park, Zambia
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Jun Yasuda; Mayumi Ishizuka
  3rd CSTS and 5th SETAC- Africa Joint Toxicology Conference, 03 Jun. 2011, English, Oral presentation
  [International presentation]
• Metal concentration and stable isotope ratio analysis (d13C and d15N) in water, sediment and fish from Lake Itezhi-tezhi, Zambia
  Shouta M.M. Nakayama; Yoshinori Ikenaka; Kaampwe Muzandu; Kennedy Choongo; Jun Yasuda; Mayumi Ishizuka
  3rd CSTS and 5th SETAC- Africa Joint Toxicology Conference, 03 Jun. 2011, English, Oral presentation
  [International presentation]