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Martin NR, Patel R, Kossack ME, Tian L, Camarillo MA, Cintrón-Rivera LG, Gawdzik JC, Yue MS, Nwagugo FO, Elemans LMH, Plavicki JS. Proper modulation of AHR signaling is necessary for establishing neural connectivity and oligodendrocyte precursor cell development in the embryonic zebrafish brain. Front Mol Neurosci 2022; 15:1032302. [PMID: 36523606 PMCID: PMC9745199 DOI: 10.3389/fnmol.2022.1032302] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 10/24/2022] [Indexed: 12/03/2022] Open
Abstract
2,3,7,8-tetrachlorodibenzo-[p]-dioxin (TCDD) is a persistent global pollutant that exhibits a high affinity for the aryl hydrocarbon receptor (AHR), a ligand activated transcription factor. Epidemiological studies have associated AHR agonist exposure with multiple human neuropathologies. Consistent with the human data, research studies using laboratory models have linked pollutant-induced AHR activation to disruptions in learning and memory as well as motor impairments. Our understanding of endogenous AHR functions in brain development is limited and, correspondingly, scientists are still determining which cell types and brain regions are sensitive to AHR modulation. To identify novel phenotypes resulting from pollutant-induced AHR activation and ahr2 loss of function, we utilized the optically transparent zebrafish model. Early embryonic TCDD exposure impaired embryonic brain morphogenesis, resulted in ventriculomegaly, and disrupted neural connectivity in the optic tectum, habenula, cerebellum, and olfactory bulb. Altered neural network formation was accompanied by reduced expression of synaptic vesicle 2. Loss of ahr2 function also impaired nascent network development, but did not affect gross brain or ventricular morphology. To determine whether neural AHR activation was sufficient to disrupt connectivity, we used the Gal4/UAS system to express a constitutively active AHR specifically in differentiated neurons and observed disruptions only in the cerebellum; thus, suggesting that the phenotypes resulting from global AHR activation likely involve multiple cell types. Consistent with this hypothesis, we found that TCDD exposure reduced the number of oligodendrocyte precursor cells and their derivatives. Together, our findings indicate that proper modulation of AHR signaling is necessary for the growth and maturation of the embryonic zebrafish brain.
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Affiliation(s)
- Nathan R. Martin
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Ratna Patel
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Michelle E. Kossack
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Lucy Tian
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Manuel A. Camarillo
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Layra G. Cintrón-Rivera
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States
| | - Joseph C. Gawdzik
- Molecular and Environmental Toxicology Center, University of Wisconsin at Madison, Madison, WI, United States,Division of Pharmaceutical Sciences, University of Wisconsin at Madison, Madison, WI, United States
| | - Monica S. Yue
- Molecular and Environmental Toxicology Center, University of Wisconsin at Madison, Madison, WI, United States,Division of Pharmaceutical Sciences, University of Wisconsin at Madison, Madison, WI, United States
| | - Favour O. Nwagugo
- Department of Biology, University of Maryland Baltimore County, Baltimore, MD, United States
| | - Loes M. H. Elemans
- Division of Toxicology, Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, Netherlands
| | - Jessica S. Plavicki
- Department of Pathology and Laboratory Medicine, Brown University, Providence, RI, United States,*Correspondence: Jessica S. Plavicki,
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Lee S, Lim Y, Kang Y, Jung K, Jee S. The Association between Blood Concentrations of PCDD/DFs, DL-PCBs and the Risk of Type 2 Diabetes Mellitus and Thyroid Cancer in South Korea. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148745. [PMID: 35886598 PMCID: PMC9320419 DOI: 10.3390/ijerph19148745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/06/2022] [Accepted: 07/14/2022] [Indexed: 02/06/2023]
Abstract
Background and Objectives: Epidemiological studies have inconsistently shown an association between dioxin and risk of type 2 diabetes mellitus (T2DM) and cancer. This study aims to examine the effects of blood concentration of dioxin-like polychlorinated biphenyls (DL-PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/DFs) on T2DM and thyroid cancer. Methods: We conducted a nested case–control study within the Korean cancer prevention study-II (KCPS-II) consisting of 15 thyroid cancer cases, 30 T2DM cases, and 55 controls. A total of 500 samples were used in 100 pooling samples. An average value of a pooled sample was calculated weighted by the blood volume of each sample. Results: The study population included 100 participants from the KCPS-II (median (IQR) baseline age, 54.06 [21.04] years; 48 women). The toxic equivalents of PCDD/DFs showed a significant positive association with T2DM and thyroid cancer, after adjustments for potential confounders (T2DM ORs = 1.23; 95% CI = 1.05–1.43; thyroid cancer ORs = 1.34; 95% CI = 1.12–1.61). Conclusion: In this study, both T2DM and thyroid cancer were associated with the blood concentrations of PCDD/DFs. The association between PCDD/DFs and T2D was found among women but not among men. Our findings suggest that further biochemical in vivo research and epidemiologic studies are needed to clarify the association between dioxins concentrations and diseases.
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Affiliation(s)
- SuHyun Lee
- Department of Epidemiology and Health Promotion, Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul 03722, Korea; (S.L.); (S.J.)
- Department of Public Health, Graduate School, Yonsei University, Seoul 03722, Korea
| | - YoungWook Lim
- Institute for Environmental Research, Yonsei University College of Medicine, Seoul 03722, Korea;
| | - YounSeok Kang
- Environment Testing Division, Eurofins Korea Ltd., Gunpo 15849, Korea;
| | - KeumJi Jung
- Department of Epidemiology and Health Promotion, Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul 03722, Korea; (S.L.); (S.J.)
- Correspondence:
| | - SunHa Jee
- Department of Epidemiology and Health Promotion, Institute for Health Promotion, Graduate School of Public Health, Yonsei University, Seoul 03722, Korea; (S.L.); (S.J.)
- Department of Public Health, Graduate School, Yonsei University, Seoul 03722, Korea
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Marsan ES, Dreab A, Bayse CA. In silico insights into the dimer structure and deiodinase activity of type III iodothyronine deiodinase from bioinformatics, molecular dynamics simulations, and QM/MM calculations. J Biomol Struct Dyn 2022:1-11. [PMID: 35579922 PMCID: PMC9878935 DOI: 10.1080/07391102.2022.2073271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The homodimeric family of iodothyronine deiodinases (Dios) regioselectively remove iodine from thyroid hormones. Currently, structural data has only been reported for the monomer of the mus type III thioredoxin (Trx) fold catalytic domain (Dio3Trx), but the mode of dimerization has not yet been determined. Various groups have proposed dimer structures that are similar to the A-type and B-type dimerization modes of peroxiredoxins. Computational methods are used to compare the sequence of Dio3Trx to related proteins known to form A-type and B-type dimers. Sequence analysis and in silico protein-protein docking methods suggest that Dio3Trx is more consistent with proteins that adopt B-type dimerization. Molecular dynamics (MD) simulations of the refined Dio3Trx dimer constructed using the SymmDock and GalaxyRefineComplex databases indicate stable dimer formation along the β4α3 interface consistent with other Trx fold B-type dimers. Free energy calculations show that the dimer is stabilized by interdimer interactions between the β-sheets and α-helices. A comparison of MD simulations of the apo and thyroxine-bound dimers suggests that the active site binding pocket is not affected by dimerization. Determination of the transition state for deiodination of thyroxine from the monomer structure using QM/MM methods provides an activation barrier consistent with previous small model DFT studies.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Eric S. Marsan
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA
| | - Ana Dreab
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA
| | - Craig A. Bayse
- Department of Chemistry and Biochemistry, Old Dominion University, Norfolk, VA
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Abstract
The thyroid hormone system is a main target of endocrine disruptor compounds (EDC) at all levels of its intricately fine-tuned feedback regulation, synthesis, distribution, metabolism and action of the 'prohormone' thyroxine and its active metabolites. Apart from classical antithyroid effects of EDC on the gland, the majority of known and suspected effects occurs at the pre-receptor control of T3 ligand availability to T3 receptors exerting ligand modulated thyroid hormone action. Tissue-, organ- and cell-specific expression and function of thyroid hormone transporters, deiodinases, metabolizing enzymes and T3-receptor forms, all integral components of the system, may mediate adverse EDC effects. Established evidence from nutritional, pharmacological and molecular genetic studies clearly support the functional, biological, and clinical relevance of these targets. Iodine-containing thyroid hormones and the organization of this system are highly conserved during evolution from primitive aquatic life forms, amphibia, birds throughout all vertebrates including humans. Mechanistic studies from various animal experimental models strongly support cause-effect relationships upon EDC exposure, hazards and adverse effects of EDC across various species. Retrospective case-control, cohort and population studies linking EDC exposure with epidemiological data on thyroid hormone-related (dys-)functions provide clear evidence that human development, especially of the fetal and neonatal brain, growth, differentiation and metabolic processes in adult and aging humans are at risk for adverse EDC effects. Considering that more than half of the world population still lives on inadequate iodine supply, the additional ubiquitous exposure to EDC and their mixtures is an additional threat for the essential thyroid hormone system, the health of the human population and their future progenies, animal life forms and our global environment.
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Affiliation(s)
- Josef Köhrle
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Experimentelle Endokrinologie, Hessische Strasse 3-4, 10115, Berlin, Germany.
| | - Caroline Frädrich
- Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institut für Experimentelle Endokrinologie, Hessische Strasse 3-4, 10115, Berlin, Germany
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Akinola LK, Uzairu A, Shallangwa GA, Abechi SE. Theoretical study on endocrine disrupting effects of polychlorinated dibenzo‐
p
‐dioxins using molecular docking simulation. J Appl Toxicol 2020; 41:233-246. [DOI: 10.1002/jat.4039] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/24/2020] [Accepted: 06/24/2020] [Indexed: 12/25/2022]
Affiliation(s)
- Lukman K. Akinola
- Department of Chemistry Ahmadu Bello University Zaria Nigeria
- Department of Chemistry Bauchi State University Gadau Nigeria
| | - Adamu Uzairu
- Department of Chemistry Ahmadu Bello University Zaria Nigeria
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Fathoming the link between anthropogenic chemical contamination and thyroid cancer. Crit Rev Oncol Hematol 2020; 150:102950. [DOI: 10.1016/j.critrevonc.2020.102950] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 02/12/2020] [Accepted: 04/02/2020] [Indexed: 01/08/2023] Open
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Dai Q, Xu X, Eskenazi B, Asante KA, Chen A, Fobil J, Bergman Å, Brennan L, Sly PD, Nnorom IC, Pascale A, Wang Q, Zeng EY, Zeng Z, Landrigan PJ, Bruné Drisse MN, Huo X. Severe dioxin-like compound (DLC) contamination in e-waste recycling areas: An under-recognized threat to local health. ENVIRONMENT INTERNATIONAL 2020; 139:105731. [PMID: 32315892 DOI: 10.1016/j.envint.2020.105731] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 04/07/2020] [Accepted: 04/07/2020] [Indexed: 02/05/2023]
Abstract
Electrical and electronic waste (e-waste) burning and recycling activities have become one of the main emission sources of dioxin-like compounds (DLCs). Workers involved in e-waste recycling operations and residents living near e-waste recycling sites (EWRS) are exposed to high levels of DLCs. Epidemiological and experimental in vivo studies have reported a range of interconnected responses in multiple systems with DLC exposure. However, due to the compositional complexity of DLCs and difficulties in assessing mixture effects of the complex mixture of e-waste-related contaminants, there are few studies concerning human health outcomes related to DLC exposure at informal EWRS. In this paper, we have reviewed the environmental levels and body burdens of DLCs at EWRS and compared them with the levels reported to be associated with observable adverse effects to assess the health risks of DLC exposure at EWRS. In general, DLC concentrations at EWRS of many countries have been decreasing in recent years due to stricter regulations on e-waste recycling activities, but the contamination status is still severe. Comparison with available data from industrial sites and well-known highly DLC contaminated areas shows that high levels of DLCs derived from crude e-waste recycling processes lead to elevated body burdens. The DLC levels in human blood and breast milk at EWRS are higher than those reported in some epidemiological studies that are related to various health impacts. The estimated total daily intakes of DLCs for people in EWRS far exceed the WHO recommended total daily intake limit. It can be inferred that people living in EWRS with high DLC contamination have higher health risks. Therefore, more well-designed epidemiological studies are urgently needed to focus on the health effects of DLC pollution in EWRS. Continuous monitoring of the temporal trends of DLC levels in EWRS after actions is of highest importance.
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Affiliation(s)
- Qingyuan Dai
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, China
| | - Xijin Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, China
| | - Brenda Eskenazi
- School of Public Health, University of California, Berkeley, USA
| | | | - Aimin Chen
- Department of Biostatistics, Epidemiology and Informatics, University of Pennsylvania, USA
| | - Julius Fobil
- School of Public Health, University of Ghana, Ghana
| | - Åke Bergman
- Department of Environmental Science, Stockholm University, Sweden; Department of Science and Technology, Örebro University, Sweden; College of Environmental Science and Engineering, Tongji University, China
| | - Lesley Brennan
- Department of Obstetrics and Gynaecology, University of Alberta, Canada
| | - Peter D Sly
- Child Health Research Centre, University of Queensland, Australia
| | | | - Antonio Pascale
- Department of Toxicology, University of the Republic, Uruguay
| | - Qihua Wang
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, China
| | - Eddy Y Zeng
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, China
| | - Zhijun Zeng
- Laboratory of Environmental Medicine and Developmental Toxicology, Shantou University Medical College, China
| | | | - Marie-Noel Bruné Drisse
- Department of Environment, Climate Change and Health, World Health Organization, Geneva, Switzerland
| | - Xia Huo
- Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, China.
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Marsan ES, Bayse CA. Halogen Bonding Interactions of Polychlorinated Biphenyls and the Potential for Thyroid Disruption. Chemistry 2020; 26:5200-5207. [PMID: 31849117 PMCID: PMC8812442 DOI: 10.1002/chem.201903904] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 12/13/2019] [Indexed: 11/21/2023]
Abstract
Polychlorinated biphenyl (PCB) flame retardants are persistent pollutants and inhibit neurodevelopment, particularly in the early stages of life. Halogen bonding (XB) to the iodothyronine deiodinases (Dio) that modulate thyroid hormones (THs) is a potential mechanism for endocrine disruption. Cl⋅⋅⋅Se XB interactions of PCBs with SeMe- , a small model of the Dio active site selenocysteine, are compared with previous results on polybrominated diphenylethers (PBDEs) and THs using density functional theory. PCBs generally display weaker XB interactions compared to PBDEs and THs, consistent with the dependence of XB strength on the size of the halogen (I>Br>Cl). PCBs also do not meet a proposed energy threshold for substrates to undergo dehalogenation, suggesting they may behave as competitive inhibitors of Dio in addition to other mechanisms of endocrine disruption. XB interactions in PCBs are position-dependent, with ortho interactions slightly more favorable than meta and para interactions, suggesting that PCBs may have a greater effect on certain classes of Dio. Flexibility of PCBs around the biphenyl C-C bond is limited by ortho substitutions relative to the biphenyl linkage, which may contribute to the ability to inhibit Dio and other TH-related proteins.
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Affiliation(s)
- Eric S Marsan
- Department of Chemistry and Biochemistry, Old Dominion University, 1 Old Dominion University, Norfolk, VA, 23529, USA
| | - Craig A Bayse
- Department of Chemistry and Biochemistry, Old Dominion University, 1 Old Dominion University, Norfolk, VA, 23529, USA
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Warner M, Rauch S, Ames J, Mocarelli P, Brambilla P, Signorini S, Eskenazi B. Prenatal dioxin exposure and thyroid hormone levels in the Seveso second generation study. ENVIRONMENTAL RESEARCH 2020; 183:109280. [PMID: 32311913 PMCID: PMC7176740 DOI: 10.1016/j.envres.2020.109280] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/14/2020] [Accepted: 02/19/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND In animal studies, perinatal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters thyroid homoeostasis and thyroid hormone concentrations; epidemiologic evidence is limited. OBJECTIVES We aimed to determine the association of prenatal exposure to TCDD with thyroid hormone concentrations in the Seveso Second Generation Study, a unique cohort of children born to TCDD-exposed women resulting from a 1976 chemical factory explosion in Seveso, Italy. METHODS We included 570 children (288 female, 282 male) with complete follow-up data, including a fasting blood draw. Serum levels of total and free thyroxine (T4), free triiodothyronine (T3), and thyroid stimulating hormone (TSH) were measured using immunoassays. We defined prenatal TCDD exposure as: 1) maternal initial TCDD concentration measured in serum collected soon after the explosion and 2) maternal TCDD estimated at pregnancy. RESULTS Compared to the lowest quartile (Q1), maternal initial serum TCDD was associated with lower free T3 (Q2: adj-β = -0.13, 95%CI -0.26, 0.00; Q3: adj-β = -0.22, 95%CI -0.35, -0.09; Q4: adj-β = -0.14, 95%CI -0.28, 0.00; p-trend = 0.02). In participants with high thyroid antibody status, inverse associations between maternal initial serum TCDD and free T3 were significantly stronger than in participants with normal antibody status (p-interaction = 0.02). We also observed a positive association between maternal initial serum TCDD and TSH concentrations in participants with high thyroid antibody status (Q2: adj-β = 11.4%, 95%CI -25.2, 66.1; Q3: adj-β = 49.0%, 95%CI 3.0, 115.5; Q4: adj-β = 105.5, 95%CI 36.6, 209.2; p-trend < 0.01) but not in those participants with normal antibody status (p-interaction < 0.01). Similar results were found for TCDD estimated at pregnancy. DISCUSSION Our results suggest prenatal exposure to TCDD, a potent endocrine-disrupting compound, may alter thyroid function later in life. Populations with additional thyroid stress may be particularly susceptible to in utero exposure of thyroid disrupting chemicals.
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Affiliation(s)
- Marcella Warner
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California at Berkeley, Berkeley, CA, USA.
| | - Stephen Rauch
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California at Berkeley, Berkeley, CA, USA
| | - Jennifer Ames
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California at Berkeley, Berkeley, CA, USA
| | - Paolo Mocarelli
- Department of Laboratory Medicine, University of Milano-Bicocca, School of Medicine, Hospital of Desio, Desio, Milano, Italy
| | - Paolo Brambilla
- Department of Laboratory Medicine, University of Milano-Bicocca, School of Medicine, Hospital of Desio, Desio, Milano, Italy
| | - Stefano Signorini
- Department of Laboratory Medicine, University of Milano-Bicocca, School of Medicine, Hospital of Desio, Desio, Milano, Italy
| | - Brenda Eskenazi
- Center for Environmental Research and Children's Health (CERCH), School of Public Health, University of California at Berkeley, Berkeley, CA, USA
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A Halogen Bonding Perspective on Iodothyronine Deiodinase Activity. Molecules 2020; 25:molecules25061328. [PMID: 32183289 PMCID: PMC7144113 DOI: 10.3390/molecules25061328] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 03/07/2020] [Accepted: 03/10/2020] [Indexed: 12/25/2022] Open
Abstract
Iodothyronine deiodinases (Dios) are involved in the regioselective removal of iodine from thyroid hormones (THs). Deiodination is essential to maintain TH homeostasis, and disruption can have detrimental effects. Halogen bonding (XB) to the selenium of the selenocysteine (Sec) residue in the Dio active site has been proposed to contribute to the mechanism for iodine removal. Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are known disruptors of various pathways of the endocrine system. Experimental evidence shows PBDEs and their hydroxylated metabolites (OH-BDEs) can inhibit Dio, while data regarding PCB inhibition are limited. These xenobiotics could inhibit Dio activity by competitively binding to the active site Sec through XB to prevent deiodination. XB interactions calculated using density functional theory (DFT) of THs, PBDEs, and PCBs to a methyl selenolate (MeSe−) arrange XB strengths in the order THs > PBDEs > PCBs in agreement with known XB trends. THs have the lowest energy C–X*-type unoccupied orbitals and overlap with the Se lp donor leads to high donor-acceptor energies and the greatest activation of the C–X bond. The higher energy C–Br* and C–Cl* orbitals similarly result in weaker donor-acceptor complexes and less activation of the C–X bond. Comparison of the I···Se interactions for the TH group suggest that a threshold XB strength may be required for dehalogenation. Only highly brominated PBDEs have binding energies in the same range as THs, suggesting that these compounds may inhibit Dio and undergo debromination. While these small models provide insight on the I···Se XB interaction itself, interactions with other active site residues are governed by regioselective preferences observed in Dios.
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Samer CF, Gloor Y, Rollason V, Guessous I, Doffey‐Lazeyras F, Saurat J, Sorg O, Desmeules J, Daali Y. Cytochrome P450 1A2 activity and incidence of thyroid disease and cancer after chronic or acute exposure to dioxins. Basic Clin Pharmacol Toxicol 2019; 126:296-303. [DOI: 10.1111/bcpt.13339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 09/26/2019] [Indexed: 12/21/2022]
Affiliation(s)
- Caroline Flora Samer
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
- Swiss Centre for Applied Human Toxicology Geneva Switzerland
| | - Yvonne Gloor
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
| | - Victoria Rollason
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
| | - Idris Guessous
- Division of Primary Care Medicine Department of Community Medicine, Primary Care and Emergency Medicine Geneva University Hospitals Geneva Switzerland
| | - Fabienne Doffey‐Lazeyras
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
| | - Jean‐Hilaire Saurat
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
- Swiss Centre for Applied Human Toxicology Geneva Switzerland
| | - Olivier Sorg
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
- Swiss Centre for Applied Human Toxicology Geneva Switzerland
| | - Jules Desmeules
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
- Swiss Centre for Applied Human Toxicology Geneva Switzerland
| | - Youssef Daali
- Division of Clinical Pharmacology and Toxicology Department of Acute Medicine Geneva University Hospitals Geneva Switzerland
- Division of Clinical Pharmacology and Toxicology Faculty of Medicine University of Geneva Geneva Switzerland
- Swiss Centre for Applied Human Toxicology Geneva Switzerland
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Knutsen HK, Alexander J, Barregård L, Bignami M, Brüschweiler B, Ceccatelli S, Cottrill B, Dinovi M, Edler L, Grasl-Kraupp B, Hogstrand C, Nebbia CS, Oswald IP, Petersen A, Rose M, Roudot AC, Schwerdtle T, Vleminckx C, Vollmer G, Wallace H, Fürst P, Håkansson H, Halldorsson T, Lundebye AK, Pohjanvirta R, Rylander L, Smith A, van Loveren H, Waalkens-Berendsen I, Zeilmaker M, Binaglia M, Gómez Ruiz JÁ, Horváth Z, Christoph E, Ciccolallo L, Ramos Bordajandi L, Steinkellner H, Hoogenboom LR. Risk for animal and human health related to the presence of dioxins and dioxin-like PCBs in feed and food. EFSA J 2018; 16:e05333. [PMID: 32625737 PMCID: PMC7009407 DOI: 10.2903/j.efsa.2018.5333] [Citation(s) in RCA: 77] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The European Commission asked EFSA for a scientific opinion on the risks for animal and human health related to the presence of dioxins (PCDD/Fs) and DL-PCBs in feed and food. The data from experimental animal and epidemiological studies were reviewed and it was decided to base the human risk assessment on effects observed in humans and to use animal data as supportive evidence. The critical effect was on semen quality, following pre- and postnatal exposure. The critical study showed a NOAEL of 7.0 pg WHO2005-TEQ/g fat in blood sampled at age 9 years based on PCDD/F-TEQs. No association was observed when including DL-PCB-TEQs. Using toxicokinetic modelling and taking into account the exposure from breastfeeding and a twofold higher intake during childhood, it was estimated that daily exposure in adolescents and adults should be below 0.25 pg TEQ/kg bw/day. The CONTAM Panel established a TWI of 2 pg TEQ/kg bw/week. With occurrence and consumption data from European countries, the mean and P95 intake of total TEQ by Adolescents, Adults, Elderly and Very Elderly varied between, respectively, 2.1 to 10.5, and 5.3 to 30.4 pg TEQ/kg bw/week, implying a considerable exceedance of the TWI. Toddlers and Other Children showed a higher exposure than older age groups, but this was accounted for when deriving the TWI. Exposure to PCDD/F-TEQ only was on average 2.4- and 2.7-fold lower for mean and P95 exposure than for total TEQ. PCDD/Fs and DL-PCBs are transferred to milk and eggs, and accumulate in fatty tissues and liver. Transfer rates and bioconcentration factors were identified for various species. The CONTAM Panel was not able to identify reference values in most farm and companion animals with the exception of NOAELs for mink, chicken and some fish species. The estimated exposure from feed for these species does not imply a risk.
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't Mannetje A, Eng A, Walls C, Dryson E, Douwes J, Bertazzi P, Ryder-Lewis S, Scott D, Brooks C, McLean D, Cheng S, Pearce N. Morbidity in New Zealand pesticide producers exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). ENVIRONMENT INTERNATIONAL 2018; 110:22-31. [PMID: 29031942 DOI: 10.1016/j.envint.2017.09.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Revised: 09/25/2017] [Accepted: 09/25/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVES To conduct a cross-sectional morbidity survey among 245 former employees of a pesticide production plant exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in New Zealand. METHODS Demographic factors and health information were collected in face-to-face interviews. TCDD, lipids, thyroid hormones, glucose and immunoglobulin G (IgG) were determined in non-fasting blood. For 111 participants, a neurological examination was conducted. Associations between health outcomes and working in a TCDD exposed job (prevalence 49%) and serum TCDD concentration≥10pg/g lipid (18%) were assessed using logistic regression whilst controlling for age, gender, smoking, body mass index and ethnicity. RESULTS Diabetes was more common in those who had worked in TCDD exposed jobs (OR 4.0, 95%CI 1.0-15.4) and in those with serum TCDD ≥10pg/g (OR 3.1, 95%CI 0.9-10.7). Non-fasting glucose levels >6.6mmol/l were more common in those with TCDD exposed jobs (OR 3.6, 95%CI 1.0-12.9), as were serum free thyroxine 4<12.8pmol/l (OR 4.5, 95%CI 1.4-14.4), triglycerides >1.7mmol/l (OR 2.5, 95%CI 1.1-5.7) and high density lipoprotein cholesterol (HDL) <1mmol/l (OR 4.0, 95%CI 1.2-13.2). IgG was negatively associated with TCDD (linear regression p=0.05). The neurological examination revealed a higher frequency of abnormal reflexes in those with serum TCDD ≥10pg/g (OR 4.8, 95%CI 1.1-21.0). CONCLUSIONS In this occupationally exposed population, TCDD was associated with an increased risk of diabetes and a range of subclinical responses in multiple systems (peripheral nervous system, immune system, thyroid hormones and lipid metabolism), several decades after last exposure. These results need to be interpreted with caution due to the small study size and the cross-sectional nature of the study.
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Affiliation(s)
- Andrea 't Mannetje
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand.
| | - Amanda Eng
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand
| | - Chris Walls
- Occupational Medicine, Auckland, New Zealand
| | - Evan Dryson
- Occupational Medicine, Auckland, New Zealand
| | - Jeroen Douwes
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand
| | - Pier Bertazzi
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | | | | | - Collin Brooks
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand
| | - Dave McLean
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand
| | - Soo Cheng
- Centre for Public Health Research, Massey University, PO Box 756, Wellington 6021, New Zealand
| | - Neil Pearce
- London School of Hygiene and Tropical Medicine, London, UK
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Jackson E, Shoemaker R, Larian N, Cassis L. Adipose Tissue as a Site of Toxin Accumulation. Compr Physiol 2017; 7:1085-1135. [PMID: 28915320 DOI: 10.1002/cphy.c160038] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We examine the role of adipose tissue, typically considered an energy storage site, as a potential site of toxicant accumulation. Although the production of most persistent organic pollutants (POPs) was banned years ago, these toxicants persist in the environment due to their resistance to biodegradation and widespread distribution in various environmental forms (e.g., vapor, sediment, and water). As a result, human exposure to these toxicants is inevitable. Largely due to their lipophilicity, POPs bioaccumulate in adipose tissue, resulting in greater body burdens of these environmental toxicants with obesity. POPs of major concern include polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins and furans (PCDDs/PCDFs), and polybrominated biphenyls and diphenyl ethers (PBBs/PBDEs), among other organic compounds. In this review, we (i) highlight the physical characteristics of toxicants that enable them to partition into and remain stored in adipose tissue, (ii) discuss the specific mechanisms of action by which these toxicants act to influence adipocyte function, and (iii) review associations between POP exposures and the development of obesity and diabetes. An area of controversy relates to the relative potential beneficial versus hazardous health effects of toxicant sequestration in adipose tissue. © 2017 American Physiological Society. Compr Physiol 7:1085-1135, 2017.
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Affiliation(s)
- Erin Jackson
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Robin Shoemaker
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Nika Larian
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
| | - Lisa Cassis
- Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
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Sun L, Zhang X, Dai F, Shen J, Ren C, Zuo C, Zhang Q. Elevated interleukin-1β in peripheral blood mononuclear cells contributes to the pathogenesis of autoimmune thyroid diseases, especially of Hashimoto thyroiditis. Endocr Res 2016; 41:185-92. [PMID: 26864865 DOI: 10.3109/07435800.2015.1124439] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE OF THE STUDY To explore the relationship between IL-1β expression and two common autoimmune thyroid diseases: Hashimoto thyroiditis (HT) and Graves' disease (GD). MATERIALS AND METHODS qRT-PCR, Quantiglo ELISA, and flow cytometry were used to evaluate the expression levels of IL-1β in serum, peripheral blood mononuclear cells (PBMCs), and thyroid tissue samples from patients with HT or GD. Local infiltration of monocytes was assessed by immunohistochemical study of patients' thyroid tissue samples. RESULTS Although no significant differences in IL-1β levels were found between samples of serum from patients with HT or GD and normal controls, we found that IL-1β mRNA and protein levels in PBMCs of HT patients were significantly higher than those of patients with GD, which were in turn higher than the level in normal controls. In addition, IL-1β mRNA was also increased in thyroid gland tissue from patients with HT compared to those with GD, and this was accompanied by increased local infiltration of monocytes into thyroid tissues. Correlation analysis of the clinical samples validated the association of high IL-1β levels with the pathogenesis of HT. CONCLUSION Our study suggests that IL-1β may be an active etiologic factor in the pathogenesis of HT and thus present a new target for novel diagnostics and treatment.
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Affiliation(s)
- Li Sun
- a Department of Endocrinology , The First Affiliated Hospital of Anhui Medical University , Hefei , Anhui , China
- b Institute of Endocrinology & Metabolism , Anhui Medical University , Hefei , Anhui , China
| | - Xiaoxu Zhang
- a Department of Endocrinology , The First Affiliated Hospital of Anhui Medical University , Hefei , Anhui , China
- b Institute of Endocrinology & Metabolism , Anhui Medical University , Hefei , Anhui , China
| | - Fang Dai
- a Department of Endocrinology , The First Affiliated Hospital of Anhui Medical University , Hefei , Anhui , China
- b Institute of Endocrinology & Metabolism , Anhui Medical University , Hefei , Anhui , China
| | - Jijia Shen
- c Department of Microbiology and Parasitology , Anhui Provincial Laboratory of Microbiology and Parasitology, Anhui Medical University , Hefei , Anhui , China
| | - Cuiping Ren
- c Department of Microbiology and Parasitology , Anhui Provincial Laboratory of Microbiology and Parasitology, Anhui Medical University , Hefei , Anhui , China
| | - Chunlin Zuo
- a Department of Endocrinology , The First Affiliated Hospital of Anhui Medical University , Hefei , Anhui , China
- b Institute of Endocrinology & Metabolism , Anhui Medical University , Hefei , Anhui , China
| | - Qiu Zhang
- a Department of Endocrinology , The First Affiliated Hospital of Anhui Medical University , Hefei , Anhui , China
- b Institute of Endocrinology & Metabolism , Anhui Medical University , Hefei , Anhui , China
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Increase of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls in human milk from China in 2007-2011. Int J Hyg Environ Health 2016; 219:843-849. [PMID: 27469530 DOI: 10.1016/j.ijheh.2016.07.013] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/28/2016] [Accepted: 07/19/2016] [Indexed: 11/23/2022]
Abstract
A national survey was conducted to determine polychlorinated dibenzo-p-dioxins and dibenofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) in human milk samples collected from 16 provinces in China to assess current exposure and temporal trends in China. The arithmetic mean concentration of total TEQ (PCDD/Fs and dl-PCBs) in 2011 is 6.7pgTEQg-1 lipid with a range of 2.9-15.4pgTEQg-1 lipid in 2011. Levels have been compared to data obtained during a previous national study conducted in 2007. The mean of PCDD/Fs has increased about 32.6% and 99.9% for total TEQ concentration (3.7pgTEQg-1 lipid in 2007 vs 4.9pgTEQg-1 lipid in 2011) and mass concentration (66.7pgg-1 lipid in 2007 vs 133.3pgg-1 lipid in 2011) during the period of 2007-2011, respectively. Continuous surveillance on PCDD/Fs and dl-PCBs in human milk is critical to evaluate the human health effect and environment impact in China.
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Le KT, Sawicki MP, Wang MB, Hershman JM, Leung AM. HIGH PREVALENCE OF AGENT ORANGE EXPOSURE AMONG THYROID CANCER PATIENTS IN THE NATIONAL VA HEALTHCARE SYSTEM. Endocr Pract 2016; 22:699-702. [PMID: 27176142 DOI: 10.4158/ep151108.or] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
OBJECTIVE Thyroid cancer is the most common endocrine malignancy and the most rapidly increasing cancer in the U.S. Little is known regarding the epidemiology and characteristics of patients with thyroid cancer within the national Veterans Health Administration (VHA) integrated healthcare system. The aim of this study was to further understand the characteristics of thyroid cancer patients in the VHA population, particularly in relation to Agent Orange exposure. METHODS This is a descriptive analysis of the VA (Veterans Affairs) Corporate Data Warehouse database from all U.S. VHA healthcare sites from October1, 1999, to December 31, 2013. Information was extracted for all thyroid cancer patients based on International Classification of Diseases-ninth revision diagnosis codes; histologic subtypes of thyroid cancer were not available. RESULTS There were 19,592 patients (86% men, 76% white, 58% married, 42% Vietnam-era Veteran) in the VHA system with a diagnosis of thyroid cancer within this 14-year study period. The gender-stratified prevalence rates of thyroid cancer among the Veteran population during the study period were 1:1,114 (women) and 1:1,023 (men), which were lower for women but similar for men, when compared to the U.S. general population in 2011 (1:350 for women and 1:1,219 for men). There was a significantly higher proportion of self-reported Agent Orange exposure among thyroid cancer patients (10.0%), compared to the general VHA population (6.2%) (P<.0001). CONCLUSION Thyroid cancer patients, in this sample, have a higher prevalence of self-reported Agent Orange exposure compared to the overall national VA patient population. ABBREVIATIONS T4 = thyroxine TCDD = 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin TSH = thyroid-stimulating hormone VA = Veterans Affairs VHA = Veterans Health Administration.
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Levy BS, Sidel VW. Adverse health consequences of the Vietnam War. Med Confl Surviv 2016; 31:162-70. [PMID: 26754766 DOI: 10.1080/13623699.2015.1090862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
The 40th anniversary of the end of the Vietnam War is a useful time to review the adverse health consequences of that war and to identify and address serious problems related to armed conflict, such as the protection of noncombatant civilians. More than 58,000 U.S. servicemembers died during the war and more than 150,000 were wounded. Many suffered from posttraumatic stress disorders and other mental disorders and from the long-term consequences of physical injuries. However, morbidity and mortality, although difficult to determine precisely, was substantially higher among the Vietnamese people, with at least two million of them dying during the course of the war. In addition, more than one million Vietnamese were forced to migrate during the war and its aftermath, including many "boat people" who died at sea during attempts to flee. Wars continue to kill and injure large numbers of noncombatant civilians and continue to damage the health-supporting infrastructure of society, expose civilians to toxic chemicals, forcibly displace many people, and divert resources away from services to benefit noncombatant civilians. Health professionals can play important roles in promoting the protection of noncombatant civilians during war and helping to prevent war and create a culture of peace.
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Affiliation(s)
- Barry S Levy
- a Department of Public Health and Community Medicine , Tufts University School of Medicine , Sherborn , MA , USA
| | - Victor W Sidel
- b Department of Medicine and Department of Healthcare Policy and Research , Weill Cornell Medical College , New York , NY , USA
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Chevrier J, Warner M, Gunier RB, Brambilla P, Eskenazi B, Mocarelli P. Serum dioxin concentrations and thyroid hormone levels in the Seveso Women's Health Study. Am J Epidemiol 2014; 180:490-8. [PMID: 25096280 DOI: 10.1093/aje/kwu160] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is a persistent environmental contaminant. Although experimental evidence suggests that TCDD alters thyroid hormone levels in rodents, human data are inconsistent. In 1976, a trichlorophenol plant exploded in Seveso, Italy. Women living in highly exposed areas were followed through the Seveso Women's Health Study. TCDD concentrations were measured in 1976 (n = 981) and 1996 (n = 260), and levels of total thyroxine, free thyroxine, free triiodothyronine, and thyroid-stimulating hormone were measured in 1996 (n = 909) and 2008 (n = 724). We used conditional multiple linear regression and marginal structural models with inverse-probability-of-treatment weights to evaluate associations and causal effects. TCDD concentration in 1976 was inversely associated with total thyroxine level in 1996 but not in 2008. Associations were stronger among women who had been exposed before menarche. Among these women, associations between total thyroxine and concurrent 1996 TCDD were slightly weaker than those with 1976 TCDD. A model including both 1976 and 1996 measurements strengthened the relationship between 1976 TCDD and total thyroxine but drove the association with 1996 TCDD to the null. TCDD exposure was not associated with levels of other thyroid hormones. TCDD exposure, particularly exposure before menarche, may have enduring impacts on women's total thyroxine levels. Initial exposure appears to be more influential than remaining body burden.
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Abbassy MA, Marei AESM, Al-Ashkar MAM, Mossa ATH. Adverse biochemical effects of various pesticides on sprayers of cotton fields in El-Behira Governorate, Egypt. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.biomag.2014.04.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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21
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Hypothyroidism and pesticide use among male private pesticide applicators in the agricultural health study. J Occup Environ Med 2014; 55:1171-8. [PMID: 24064777 DOI: 10.1097/jom.0b013e31829b290b] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE Evaluate the association between thyroid disease and use of insecticides, herbicides, and fumigants/fungicides in male applicators in the Agricultural Health Study. METHODS We examined the association between use of 50 specific pesticides and self-reported hypothyroidism, hyperthyroidism, and "other" thyroid disease among 22,246 male pesticide applicators. RESULTS There was increased odds of hypothyroidism with ever use of the herbicides 2,4-D (2,4-dichlorophenoxyacetic acid), 2,4,5-T (2,4,5-trichlorophenoxyacetic acid), 2,4,5-TP (2,4,5-trichlorophenoxy-propionic acid), alachlor, dicamba, and petroleum oil. Hypothyroidism was also associated with ever use of eight insecticides: organochlorines chlordane, dichlorodiphenyltrichloroethane (DDT), heptachlor, lindane, and toxaphene; organophosphates diazinon and malathion; and the carbamate carbofuran. Exposure-response analysis showed increasing odds with increasing level of exposure for the herbicides alachlor and 2,4-D and the insecticides aldrin, chlordane, DDT, lindane, and parathion. CONCLUSION There is an association between hypothyroidism and specific herbicides and insecticides in male applicators, similar to previous results for spouses.
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Pavuk M, Patterson DG, Turner WE. Serum concentrations of TCDD and other dioxin-like compounds in US Air Force veterans of Operation Ranch Hand. CHEMOSPHERE 2014; 102:18-23. [PMID: 24377449 DOI: 10.1016/j.chemosphere.2013.12.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 10/30/2013] [Accepted: 12/01/2013] [Indexed: 06/03/2023]
Abstract
We measured serum concentrations of seven dibenzo-p-dioxin congeners (PCDDs), ten dibenzofurans (PCDFs), four non-ortho polychlorinated biphenyls (noPCBs) and six mono-ortho polychlorinated biphenyls (moPCBs) in 1950 veterans of the Vietnam War. The veterans were participants in the Air Force Health Study (AFHS) who attended the final medical examination in 2002. Blood samples were collected from 777 Ranch Hands involved in the aerial spraying of herbicides in Vietnam and a comparison group of 1173 veterans ("Comparisons") who served in Southeast Asia during the same time period. Results for moPCBs were based on a random subsample of 800 veterans. The median 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) concentrations in 2002 were 5.0 pg g(-1) lipid in Ranch Hands and 2.2 pg g(-1) lipid in Comparisons. No substantial differences were found in measured concentrations of other PCDDs, PCDFs, and noPCBs. Similarly, no substantial differences were found for moPCBs in the subsample. The median total dioxin toxic equivalent (TEQ) in Ranch Hands was 18.7 pg g(-1) lipid for PCDDs, 3.4 pg g(-1) lipid for PCDFs, and 3.2 pg g(-1) lipid for noPCBs. Median TEQs in Comparisons were 14.4 pg g(-1) lipid for PCDDs, 3.5 pg g(-1) lipid for PCDFs, and 3.3 pg g(-1) lipid for noPCBs. These TEQs, with the exception of PCDD TEQ in Ranch Hands (primarily due to elevated TCDD), were similar to or lower than those reported for similar age and gender groups in the 2001-2002 National Health and Nutrition Examination Survey (NHANES). These findings support the assumption that the Ranch Hand veterans were not more highly exposed to dioxin-like compounds other than TCDD than were Comparison veterans or the general US population.
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Affiliation(s)
- Marian Pavuk
- SpecPro Inc., San Antonio, TX, USA; Division of Toxicology and Human Health Sciences, Agency for Toxic Substances and Disease Registry, 4770 Buford Highway, Mailstop F-58, Atlanta, GA 30341, USA.
| | | | - Wayman E Turner
- Organic Analytical Toxicology Branch, Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, 4770 Buford Highway, Mail Stop F-17, Atlanta, GA 30341, USA
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Guo H, Peng D, Yang XG, Wang Y, Xu BC, Ni JS, Meng W, Jiang YF. A higher frequency of circulating IL-22(+)CD4(+) T cells in Chinese patients with newly diagnosed Hashimoto's thyroiditis. PLoS One 2014; 9:e84545. [PMID: 24404171 PMCID: PMC3880314 DOI: 10.1371/journal.pone.0084545] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Accepted: 11/16/2013] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND IL-22 and IL-17A are implicated in the pathogenesis of autoimmune diseases. However, the role of IL-22(+) and IL-17A(+) CD4(+) T cells in the pathogenesis of Hashimoto's thyroiditis (HT) is not fully understood. This study investigates serum IL-22 and IL-17A levels and determines the frequency of circulating IL-22(+) CD4(+) T cells in HT patients to understand their roles in the pathogenesis of HT. METHODS The levels of serum IL-22, IL-17A and IFN-γ and the frequency of circulating IL-22(+)CD4(+) and IL-17A(+)CD4(+) T cells in 17 HT patients and 17 healthy controls (HC) were determined by enzyme-linked immunosorbent assay (ELISA) and flow cytometry. The levels of serum free triiodothyronine (FT4), free thyroxine (FT3), thyroid stimulating hormone (TSH), anti-thyroid peroxidase (TPO) and anti-thyroglobulin antibodies (TgAb) by chemiluminescent enzyme immunoassay and radioimmunoassay. RESULTS The percentages of circulating IL-22(+)CD4(+) and IL-17(+)CD4(+) T cells (p<0.0001, p<0.0001) and the levels of serum IL-22, IL-17A and IFN-γ (p<0.0001, p<0.0001, p = 0.0210) in the HT patients were significantly higher than that in the HC. The percentages of IL-22(+)CD4(+) T cells were positively correlated with Th17 cells (r = 0.8815, p<0.0001) and IL-17A(+)IL-22(+)CD4(+) T cells (r = 0.8914, p<0.0001), but were negatively correlated with Th1 cells (r = -0.6110, p<0.0092) in the HT patients. The percentages of Th22 cells, Th17 cells and IL-17A(+)IL-22(+)CD4(+) T cells were negatively correlated with the levels of serum TSH in the HT patients (r = -0.8402, p<0.0001; r = -0.8589, p<0.0001; r = -0.8289 p<0.0001, respectively). CONCLUSIONS A higher frequency of circulating IL-22(+)CD4(+) and IL-17A(+)CD4(+) T cells may be associated with the development of HT in Chinese patients.
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Affiliation(s)
- Hui Guo
- Department of Endocrinology, The Second Part of the First Hospital, Jilin University, Changchun, China
| | - Di Peng
- Key Laboratory for Zoonosis Research, Department of Central Laboratory, The First Hospital, Jilin University, Changchun, China
- Department of Endocrinology, The Second Part of the First Hospital, Jilin University, Changchun, China
| | - Xi-Ge Yang
- Department of Anesthesiology, The First Hospital, Jilin University, Changchun, China
| | - Ye Wang
- Key Laboratory for Zoonosis Research, Department of Central Laboratory, The First Hospital, Jilin University, Changchun, China
- Department of Endocrinology, The Second Part of the First Hospital, Jilin University, Changchun, China
| | - Bing-Chuan Xu
- Key Laboratory for Zoonosis Research, Department of Central Laboratory, The First Hospital, Jilin University, Changchun, China
- Department of Endocrinology, The Second Part of the First Hospital, Jilin University, Changchun, China
| | - Jin-Song Ni
- Department of Pathology, The Second Part of the First Hospital, Jilin University, Changchun, China
| | - Wei Meng
- Department of Thyroid Surgery, The First Hospital, Jilin University, Changchun, China
| | - Yan-Fang Jiang
- Key Laboratory for Zoonosis Research, Department of Central Laboratory, The First Hospital, Jilin University, Changchun, China
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Kido T, Dao TV, Ho MD, Duc Dang N, Pham NT, Okamoto R, Pham TT, Maruzeni S, Nishijo M, Nakagawa H, Honma S, Le SK, Nguyen HN. High cortisol and cortisone levels are associated with breast milk dioxin concentrations in Vietnamese women. Eur J Endocrinol 2014; 170:131-9. [PMID: 24123093 DOI: 10.1530/eje-13-0410] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Dioxin (polychlorinated dibenzodioxins+polychlorinated dibenzofurans) is one of the most toxic chemical substances known. Although it is suspected to cause endocrine disruption, very few epidemiological studies have been carried out on its effects on human steroid hormones. The aim of this study was to elucidate the association of dioxin exposure with steroid hormone levels in the saliva and serum of Vietnamese women. STUDY DESIGN Two areas, namely Phu Cat (hot spot) and Kim Bang (nonexposed area), were selected for the study. The study subjects consisted of 51 and 58 women respectively. Saliva, blood, and breast milk samples were collected from the subjects in both the areas. METHODS Cortisol, cortisone, DHEA, androstenedione, estrone, and estradiol levels in serum and saliva were determined by liquid chromatography-tandem mass spectrometry; dioxin concentrations in breast milk were measured by gas chromatography-mass spectrometry. RESULTS Dioxin concentrations in the breast milk of women from the dioxin hot spot were three to four times higher than those in the breast milk of women from the nonexposed area. Good correlations were found between the levels of six steroid hormones in saliva and those in serum respectively. Salivary and serum cortisol and cortisone levels in women from the dioxin hot spot were significantly higher than those in women from the nonexposed area (P<0.001) and those in all the subjects were positively associated with dioxin concentrations in Vietnamese women (P<0.01). CONCLUSION These results suggest that dioxin influences steroidogenesis in humans. Saliva samples can be used for hormone analysis and are therefore excellent specimens in epidemiological studies.
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Affiliation(s)
- Teruhiko Kido
- School of Health Sciences, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 5-11-80 Kodatsuno, Kanazawa, Ishikawa, Japan
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Jain RB. Association between thyroid profile and perfluoroalkyl acids: data from NHNAES 2007-2008. ENVIRONMENTAL RESEARCH 2013; 126:51-9. [PMID: 24053974 DOI: 10.1016/j.envres.2013.08.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/20/2013] [Accepted: 08/19/2013] [Indexed: 05/05/2023]
Abstract
The effect of six perfluoroalkyl acids (PFAAs), namely, perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), perfluorodecanoic acid (PFDE), perfluorohexane sulfonic acid (PFHxS), 2-(N-methyl-perfluorooctane sulfonamide) acetic acid (MPAH), and perfluorononanoic acid (PFNA) on the levels of six thyroid function variables, namely, thyroid stimulating hormone (TSH), free and total thyroxine (FT4, TT4), free and total triiodothyronine (FT3, TT3), and thyroglobulin (TGN) was evaluated. Data from National Health and Nutrition Examination Survey for the years 2007-2008 were used for this evaluation. TSH levels increased with increase in levels of PFOA (p<0.01). There were no statistically significant associations between the levels of FT3, and FT4 with the levels of any of the six PFAAs. Levels of TT3 were found to increase with the levels of PFOA (p=0.01) and TT4 levels were found to increase with increase in PFHxS levels (p<0.01). Males had statistically significantly higher levels of FT3 than females and females had statistically significantly higher levels of TT4 than males. As compared to non-Hispanics whites and Hispanics, non-Hispanic blacks had lower levels of TSH, FT3, TT3, and TT4 but Hispanics had the lowest levels of TGN. Age was negatively associated with FT3 and TT3 but positively associated with FT4 and TT4. Non-smokers had higher levels of TSH and TT4 than smokers and smokers had higher levels of FT3 and TGN than non-smokers. Iodine deficiency was associated with increased levels of TSH, TT3, TT4, and TGN.
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Affiliation(s)
- Ram B Jain
- 1061 Albemarle Way, Lawrenceville, GA 30044, United States.
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Bonassi S, Taioli E, Vermeulen R. Omics in population studies: a molecular epidemiology perspective. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2013; 54:455-460. [PMID: 23908054 DOI: 10.1002/em.21805] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 06/19/2013] [Indexed: 06/02/2023]
Abstract
The convergence of striking developments in (bio)-technology, increasing availability of biobanked samples, and advances in biostatistics and bio-informatics allow an optimistic outlook for epidemiological research. In this special issue on Omics in Population Studies: A Molecular Epidemiology Perspective we explore and reflect on the potential of these new developments in both exposure science and clinical research since they provide the essential link between exposure and disease and may enable scientists to improve their understanding of disease origin and progression. As noted in this special issue, this is an exciting time for epidemiology. While cancer and other noncommunicable diseases rise in number worldwide, various new tools can be applied effectively to increase understanding of the underlying causes and potential for progression to improve their prevention and treatment.
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Affiliation(s)
- Stefano Bonassi
- Unit of Clinical and Molecular Epidemiology, Area of Systems Approaches and Non Communicable Diseases. IRCCS San Raffaele Pisana, Rome, Italy.
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Trnovec T, Jusko TA, Šovčíková E, Lancz K, Chovancová J, Patayová H, Palkovičová L, Drobná B, Langer P, Van den Berg M, Dedik L, Wimmerová S. Relative effect potency estimates of dioxin-like activity for dioxins, furans, and dioxin-like PCBs in adults based on two thyroid outcomes. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:886-92. [PMID: 23665575 PMCID: PMC3734489 DOI: 10.1289/ehp.1205739] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 05/01/2013] [Indexed: 05/04/2023]
Abstract
BACKGROUND Toxic equivalency factors (TEFs) are an important component in the risk assessment of dioxin-like human exposures. At present, this concept is based mainly on in vivo animal experiments using oral dosage. Consequently, the current human TEFs derived from mammalian experiments are applicable only for exposure situations in which oral ingestion occurs. Nevertheless, these "intake" TEFs are commonly-but incorrectly-used by regulatory authorities to calculate "systemic" toxic equivalents (TEQs) based on human blood and tissue concentrations, which are used as biomarkers for either exposure or effect. OBJECTIVES We sought to determine relative effect potencies (REPs) for systemic human concentrations of dioxin-like mixture components using thyroid volume or serum free thyroxine (FT4) concentration as the outcomes of interest. METHODS We used a benchmark concentration and a regression-based approach to compare the strength of association between each dioxin-like compound and the thyroid end points in 320 adults residing in an organochlorine-polluted area of eastern Slovakia. RESULTS REPs calculated from thyroid volume and FT4 were similar. The regression coefficient (β)-derived REP data from thyroid volume and FT4 level were correlated with the World Health Organization (WHO) TEF values (Spearman r = 0.69, p = 0.01 and r = 0.62, p = 0.03, respectively). The calculated REPs were mostly within the minimum and maximum values for in vivo REPs derived by other investigators. CONCLUSIONS Our REPs calculated from thyroid end points realistically reflect human exposure scenarios because they are based on chronic, low-dose human exposures and on biomarkers reflecting body burden. Compared with previous results, our REPs suggest higher sensitivity to the effects of dioxin-like compounds.
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Humblet O, Korrick SA, Williams PL, Sergeyev O, Emond C, Birnbaum LS, Burns JS, Altshul LM, Patterson DG, Turner WE, Lee MM, Revich B, Hauser R. Genetic modification of the association between peripubertal dioxin exposure and pubertal onset in a cohort of Russian boys. ENVIRONMENTAL HEALTH PERSPECTIVES 2013; 121:111-117. [PMID: 23060366 PMCID: PMC3546349 DOI: 10.1289/ehp.1205278] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 10/10/2012] [Indexed: 06/01/2023]
Abstract
BACKGROUND Exposure to dioxins has been associated with delayed pubertal onset in both epidemiologic and animal studies. Whether genetic polymorphisms may modify this association is currently unknown. Identifying such genes could provide insight into mechanistic pathways. This is one of the first studies to assess genetic susceptibility to dioxins. OBJECTIVES We evaluated whether common polymorphisms in genes affecting either molecular responses to dioxin exposure or pubertal onset influence the association between peripubertal serum dioxin concentration and male pubertal onset. METHODS In this prospective cohort of Russian adolescent boys (n = 392), we assessed gene-environment interactions for 337 tagging single-nucleotide polymorphisms (SNPs) from 46 candidate genes and two intergenic regions. Dioxins were measured in the boys' serum at age 8-9 years. Pubertal onset was based on testicular volume and on genitalia staging. Statistical approaches for controlling for multiple testing were used, both with and without prescreening for marginal genetic associations. RESULTS After accounting for multiple testing, two tag SNPs in the glucocorticoid receptor (GR/NR3C1) gene and one in the estrogen receptor-α (ESR1) gene were significant (q < 0.2) modifiers of the association between peripubertal serum dioxin concentration and male pubertal onset defined by genitalia staging, although not by testicular volume. The results were sensitive to whether multiple comparison adjustment was applied to all gene-environment tests or only to those with marginal genetic associations. CONCLUSIONS Common genetic polymorphisms in the glucocorticoid receptor and estrogen receptor-α genes may modify the association between peripubertal serum dioxin concentration and pubertal onset. Further studies are warranted to confirm these findings.
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Affiliation(s)
- Olivier Humblet
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts 02115, USA
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Fernandez MF, Parera J, Arrebola JP, Marina LS, Vrijheid M, Llop S, Abalos M, Tardon A, Castaño A, Abad E, Olea N. Levels of polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls in placentas from the Spanish INMA birth cohort study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2012; 441:49-56. [PMID: 23134768 DOI: 10.1016/j.scitotenv.2012.09.075] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Revised: 09/01/2012] [Accepted: 09/28/2012] [Indexed: 06/01/2023]
Abstract
Because fetuses are considered significantly more sensitive to various environment toxicants, there is a need for continuous biomonitoring of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls PCBs (DL-PCBs) to assess their impact on this susceptible population. The aim of this study was to assess the concentration of PCDD/Fs and DL-PCBs in placenta samples from women participating in the Spanish Environment and Childhood (INMA) birth cohort study and to evaluate whether maternal and child characteristics predict placenta concentrations of these pollutants. The presence of PCDD/Fs and DL-PCBs was investigated in 50 placenta samples selected at random in the recruitment period 2000-2008. Multivariable regression models were constructed. Mothers had a mean age at delivery of 30.7 years (18.0-38.0 years), pre-pregnancy BMI of 23.3 kg/m² (18.0-40.2 kg/m²), and 31% were smokers. Median total concentrations of PCDD/Fs and DL-PCBs were 6.9 pg WHO-TEQ/g lipid and 2.1 pg WHO-TEQ/g lipid, respectively. In comparison to the few previous studies in placenta, total TEQ levels were among the lowest recorded in comparable general populations. The congener distribution pattern and the frequencies and concentrations of PCDD/F and DL-PCB congeners were similar to previous reports in placenta. PCDD/F and DL-PCB exposure was related to the age of the mother and the year of the delivery. Although placental concentrations cannot be considered wholly appropriate predictors for evaluating fetal exposure to these contaminants, they can provide a good indication of both maternal and infant prenatal and postnatal exposure and can be used as a proxy for fetal exposure.
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Affiliation(s)
- Mariana F Fernandez
- Biomedical Research Center, University of Granada, Laboratory of Medical Investigations, San Cecilio University Hospital, Granada, Spain.
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Kim JB, Kang WY, Moon SG, Kim HJ, Kim KH, Kim YH, Hwang SH, Hwang SH, Kim W. Clinical outcome of veterans with acute coronary syndrome who had been exposed to agent orange. Chonnam Med J 2012; 48:47-51. [PMID: 22570815 PMCID: PMC3341437 DOI: 10.4068/cmj.2012.48.1.47] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Accepted: 03/19/2012] [Indexed: 11/06/2022] Open
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD), one of the components of Agent Orange, has been reported to be a deadly poison despite its presence at extremely small doses. TCDD is reported to cause various kinds of cancers and other harmful effects on humans. However, a correlation between exposure to TCDD and acute coronary syndrome (ACS) is not yet proven. Thus, we examined the correlation between exposure to TCDD and ACS through an analysis of coronary angiograms from veterans of the Vietnam War. Two hundred fifty-one consecutive men undergoing coronary angiograms owing to ACS between April 2004 and May 2009 at Gwangju Veterans Hospital were analyzed. Included subjects were between 50 and 70 years of age. The patients were divided into two groups: 121 patients who had been exposed to TCDD (Group I) and 130 patients who had not been exposed to TCDD (Group II). Clinical and coronary angiographic findings were evaluated. Baseline clinical characteristics, inflammatory markers, and echocardiographic parameters were not significantly different between the two groups. The incidence of hypertension (71.1% vs. 60.0%, p=0.039) and hyperlipidemia (27.3% vs. 16.9%, p=0.038) was higher in Group I than in Group II. Total occlusion, stent length, stent use, and coronary lesion characteristics were not significantly different between the two groups. The rate of major adverse cardiovascular events (MACE) had no relationship with exposure to TCDD. Exposure to TCDD might not affect severity or the rate of MACE in persons with ACS.
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Affiliation(s)
- Jong Bum Kim
- Department of Internal Medicine, Gwangju Veterans Hospital, Gwangju, Korea
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Todaka T, Hirakawa H, Kajiwara J, Onozuka D, Sasaki S, Miyashita C, Yoshioka E, Yuasa M, Kishi R, Iida T, Uchi H, Furue M. Concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in blood and breast milk collected from pregnant women in Sapporo City, Japan. CHEMOSPHERE 2011; 85:1694-1700. [PMID: 22004731 DOI: 10.1016/j.chemosphere.2011.09.014] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2010] [Revised: 08/09/2011] [Accepted: 09/22/2011] [Indexed: 05/31/2023]
Abstract
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), and non-dioxin-like PCBs in paired samples of blood and breast milk collected from 67 secundiparas in Sapporo City, Japan, and combined this data with those of the 30 secundiparas previously measured. The arithmetic mean total toxic equivalents (TEQ-WHO) concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of the 97 secundiparous subjects were 3.0-23 (mean: 13, median: 14) and 2.7-20 (mean: 8.6, median: 8.5) pg TEQ g(-1) lipid, respectively. The sums of the concentrations of 56 non-dioxin-like PCB congeners that were measured in the subjects' blood and breast milk were 16-326 (mean: 107, median: 100) and 12-252 (mean: 73, median: 67) ng g(-1) lipid, respectively. The partitioning ratios of individual congeners of PCDDs, PCDFs, dioxin-like PCBs, and non-dioxin-like PCBs from blood to breast milk in secundiparas were almost the same as those of primiparas that have been recently reported, suggesting that the partitioning ratios of these compounds from maternal blood to breast milk in women is little affected by delivery. Furthermore, the partition of PCB congeners with chlorine at the 2-, 3-, 4'-, and 5-positions or the 2-, 4-, 4'-, and 5-positions of the biphenyl ring from the blood to the breast milk tended to occur at a higher level than that of other congeners. In particular, the levels of tetraCB-74 and hexaCB-146 in the breast milk for both primiparous and secundiparous mothers were slightly higher than those in the blood.
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Affiliation(s)
- Takashi Todaka
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan.
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Spaulding SW. The possible roles of environmental factors and the aryl hydrocarbon receptor in the prevalence of thyroid diseases in Vietnam era veterans. Curr Opin Endocrinol Diabetes Obes 2011; 18:315-20. [PMID: 21825977 DOI: 10.1097/med.0b013e32834a8764] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
PURPOSE OF REVIEW 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) profoundly affects the immune system in experimental animals. TCDD was a contaminant in defoliants used in the Vietnam War, and is known to cause prolonged activation of the aryl hydrocarbon receptor (AhR) in humans. Chronic exposure to TCDD is associated with an increased prevalence of certain chronic diseases, lymphomas and leukemias. The AhR is a transcription factor that responds to cellular metabolites as well as to environmental substances. We review how TCDD and the AhR alter thyroid metabolism directly, and how recent experimental and clinical findings on TCDD and immunity are related to autoimmune thyroid diseases. RECENT FINDINGS TCDD exaggerates the normal responses of the AhR to endogenous activators, affecting dendritic cells, regulatory T cells (T(reg)), T(helper)17 (T(h)17) and T(helper)22 (T(h)22) cells. A recent study on approximately 225 000 veterans of the Vietnam era found that those who served in Vietnam or were otherwise exposed to defoliants had a 2.5-fold to three-fold higher prevalence of the diagnosis of Graves' disease, compared to Veterans who served elsewhere. SUMMARY The balance between T(reg), T(h)17 and T(h)22 cells is disrupted by TCDD, resembling what has been found clinically in Graves' disease and Hashimoto's thyroiditis, and in animal models of these diseases. By altering the immune balance in susceptible individuals, chronic TCDD exposure may influence the prevalence of autoimmune thyroid diseases.
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Hartoft-Nielsen ML, Boas M, Bliddal S, Rasmussen AK, Main K, Feldt-Rasmussen U. Do Thyroid Disrupting Chemicals Influence Foetal Development during Pregnancy? J Thyroid Res 2011; 2011:342189. [PMID: 21918727 PMCID: PMC3170895 DOI: 10.4061/2011/342189] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2011] [Revised: 05/13/2011] [Accepted: 06/02/2011] [Indexed: 11/20/2022] Open
Abstract
Maternal euthyroidism during pregnancy is crucial for normal development and, in particular, neurodevelopment of the foetus. Up to 3.5 percent of pregnant women suffer from hypothyroidism. Industrial use of various chemicals—endocrine disrupting chemicals (EDCs)—has been shown to cause almost constant exposure of humans with possible harmful influence on health and hormone regulation. EDCs may affect thyroid hormone homeostasis by different mechanisms, and though the effect of each chemical seems scarce, the added effects may cause inappropriate consequences on, for example, foetal neurodevelopment.
This paper focuses on thyroid hormone influence on foetal development in relation to the chemicals suspected of thyroid disrupting properties with possible interactions with maternal thyroid homeostasis. Knowledge of the effects is expected to impact the general debate on the use of these chemicals. However, more studies are needed to elucidate the issue, since human studies are scarce.
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Affiliation(s)
- Marie-Louise Hartoft-Nielsen
- Department of Medical Endocrinology PE-2131, Rigshospitalet, University Hospital of Copenhagen, 2100 Copenhagen, Denmark
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Foster WG, Maharaj-Briceño S, Cyr DG. Dioxin-induced changes in epididymal sperm count and spermatogenesis. CIENCIA & SAUDE COLETIVA 2011; 16:2893-905. [DOI: 10.1590/s1413-81232011000600027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 12/17/2009] [Indexed: 11/22/2022] Open
Abstract
A single in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gestation day 15 decreased epididymal sperm count in adult rats and thus was used to establish a tolerable daily intake for TCDD. However, several laboratories have been unable to replicate these findings. Moreover, conflicting reports of TCDD effects on daily sperm production suggest that spermatogenesis may not be as sensitive to the adverse effects of TCDD as previously thought. We performed a PubMed search using relevant search terms linking dioxin exposure with adverse effects on reproduction and spermatogenesis. Developmental exposure to TCDD is consistently linked with decreased cauda epididymal sperm counts in animal studies, although at higher dose levels than those used in some earlier studies. However, the evidence linking in utero TCDD exposure and spermatogenesis is not convincing. Animal studies provide clear evidence of an adverse effect of in utero TCDD exposure on epididymal sperm count but do not support the conclusion that spermatogenesis is adversely affected. The mechanisms underlying decreased epididymal sperm count are unknown; however, we postulate that epididymal function is the key target for the adverse effects of TCDD.
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Yoshizawa K, Walker NJ, Nyska A, Kissling GE, Jokinen MP, Brix AE, Sells DM, Wyde ME. Thyroid follicular lesions induced by oral treatment for 2 years with 2,3,7,8-tetrachlorodibenzo-p-dioxin and dioxin-like compounds in female Harlan Sprague-Dawley rats. Toxicol Pathol 2010; 38:1037-50. [PMID: 20924081 DOI: 10.1177/0192623310382560] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) and structurally-similar dioxin-like compounds affect thyroid function and morphology and thyroid hormone metabolism in animals and humans. The National Toxicology Program conducted eight 2-year gavage studies in female Harlan Sprague-Dawley rats to determine the relative potency of chronic toxicity and carcinogenicity of TCDD, 3,3',4,4',5-pentachlorobiphenyl (PCB126), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), 2,3',4,4',5-pentachlorobiphenyl (PCB118), 2,2',4,4',5,5'-hexachloro-biphenyl (PCB153), a tertiary mixture of TCDD/PCB126/PeCDF, and two binary mixtures (PCB126/PCB153 and PCB126/PCB118). Administration of these compounds was associated with increased incidences of thyroid follicular cell hypertrophy, variably observed in the 14-, 31-, and 53-week interim and 2-year sacrifice groups. In all studies, the incidences of follicular cell adenoma and carcinoma were not increased. Decreased levels of serum thyroxine were primarily noted in the 14-or-later -week interim groups of all chemicals. Serum triiodothyronine (T3) levels were increased in the TCDD, PCB126, PeCDF, TCDD/PCB126/PeCDF, and PCB126/PCB153 studies, while decreased levels were noted in the PCB153 and PCB126/PCB118 studies. TCDD, PCB126, PCB126/PCB153, and PCB126/PCB118 increased levels of serum thyroid-stimulating hormone almost in a dose-dependent manner in the 14-week groups. These data suggest that although dioxin-like compounds alter thyroid hormones and increase follicular cell hyperplasia, there is not an increase in thyroid adenoma or carcinoma in female Sprague-Dawley rats.
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Humblet O, Williams PL, Korrick SA, Sergeyev O, Emond C, Birnbaum LS, Burns JS, Altshul L, Patterson DG, Turner WE, Lee MM, Revich B, Hauser R. Predictors of serum dioxin, furan, and PCB concentrations among women from Chapaevsk, Russia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:5633-40. [PMID: 20578718 PMCID: PMC3128795 DOI: 10.1021/es100976j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Dioxins, furans, and polychlorinated biphenyls (PCBs) are persistent and bioaccumulative toxic chemicals that are ubiquitous in the environment. We assessed predictors of their serum concentrations among women living in a Russian town contaminated by past industrial activity. Blood samples from 446 mothers aged 23-52 years were collected between 2003-2005 as part of the Russian Children's Study. Serum dioxin, furan, and PCB concentrations were quantified using high-resolution gas chromatography-mass spectrometry. Potential determinants of exposure were collected through interviews. Multivariate linear regression models were used to identify predictors of serum concentrations and toxic equivalencies (TEQs). The median total PCB concentrations and total TEQs were 260 ng/g lipid and 25 pg TEQ/g lipid, respectively. In multivariate analyses, both total PCB concentrations and total TEQs increased significantly with age, residential proximity to a local chemical plant, duration of local farming, and consumption of local beef. Both decreased with longer breastfeeding, recent increases in body mass index, and later blood draw date. These demographic and lifestyle predictors showed generally similar associations with the various measures of serum dioxins, furans, and PCBs.
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Affiliation(s)
- Olivier Humblet
- Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
| | - Paige L. Williams
- Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts
| | - Susan A. Korrick
- Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
- Channing Laboratory, Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, Massachusetts
| | - Oleg Sergeyev
- Department of Physical Education and Health, Samara State Medical University, Samara, Russia
- Chapaevsk Medical Association, Chapaevsk, Russia
| | - Claude Emond
- Department of Environmental and Occupational Health, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada
| | - Linda S. Birnbaum
- National Institute for Environmental Health Sciences and National Toxicology Program, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina
| | - Jane S. Burns
- Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
| | - Larisa Altshul
- Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
- Environmental Health and Engineering, Inc., Needham, Massachusetts
| | | | | | - Mary M. Lee
- Pediatric Endocrinology Division, Departments of Pediatrics and Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts
| | - Boris Revich
- Center for Demography and Human Ecology, Institute for Forecasting, Russian Academy of Sciences, Moscow, Russia
| | - Russ Hauser
- Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, Boston, Massachusetts
- Corresponding author: Russ Hauser, MD, ScD, MPH, Environmental and Occupational Medicine and Epidemiology Program, Department of Environmental Health, Harvard School of Public Health, 665 Huntington Avenue, Building I, room 1405, Boston, MA 02115,
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Gim J, Kim HS, Kim J, Choi M, Kim JR, Chung YJ, Cho KH. A system-level investigation into the cellular toxic response mechanism mediated by AhR signal transduction pathway. Bioinformatics 2010; 26:2169-75. [DOI: 10.1093/bioinformatics/btq400] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Foster WG, Maharaj-Briceño S, Cyr DG. Dioxin-induced changes in epididymal sperm count and spermatogenesis. ENVIRONMENTAL HEALTH PERSPECTIVES 2010; 118:458-64. [PMID: 20368131 PMCID: PMC2854720 DOI: 10.1289/ehp.0901084] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Accepted: 12/17/2009] [Indexed: 05/24/2023]
Abstract
BACKGROUND A single in utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on gestation day 15 decreased epididymal sperm count in adult rats and thus was used to establish a tolerable daily intake for TCDD. However, several laboratories have been unable to replicate these findings. Moreover, conflicting reports of TCDD effects on daily sperm production suggest that spermatogenesis may not be as sensitive to the adverse effects of TCDD as previously thought. DATA SOURCES We performed a PubMed search using relevant search terms linking dioxin exposure with adverse effects on reproduction and spermatogenesis. DATA SYNTHESIS Developmental exposure to TCDD is consistently linked with decreased cauda epididymal sperm counts in animal studies, although at higher dose levels than those used in some earlier studies. However, the evidence linking in utero TCDD exposure and spermatogenesis is not convincing. CONCLUSIONS Animal studies provide clear evidence of an adverse effect of in utero TCDD exposure on epididymal sperm count but do not support the conclusion that spermatogenesis is adversely affected. The mechanisms underlying decreased epididymal sperm count are unknown; however, we postulate that epididymal function is the key target for the adverse effects of TCDD.
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Affiliation(s)
- Warren G Foster
- Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada.
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Todaka T, Hirakawa H, Kajiwara J, Hori T, Tobiishi K, Yasutake D, Onozuka D, Sasaki S, Miyashita C, Yoshioka E, Yuasa M, Kishi R, Iida T, Furue M. Relationship between the concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and polychlorinated biphenyls in maternal blood and those in breast milk. CHEMOSPHERE 2010; 78:185-192. [PMID: 19850319 DOI: 10.1016/j.chemosphere.2009.09.047] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2009] [Revised: 09/17/2009] [Accepted: 09/18/2009] [Indexed: 05/28/2023]
Abstract
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like polychlorinated biphenyls (PCBs), and non-dioxin-like PCBs in paired samples of blood and breast milk collected from 89 primiparous mothers in Sapporo City, Japan, and studied the relationships of these compounds between blood and breast milk for these women plus 30 primiparous mothers in whom these data had been previously reported. The present study is one of the few studies in which the concentration distributions of PCDDs, PCDFs, dioxin-like PCBs, and non-dioxin-like PCBs have been investigated in blood and breast milk collected from the same mothers. The arithmetic mean TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of these 119 subjects were 8.2, 2.9, 5.1, and 0.4 pg TEQ g(-1)lipid, respectively, and 4.8, 2.0, 4.0, and 0.4 pg TEQ g(-1)lipid, respectively, with the total TEQ concentrations of these dioxin-like compounds being 7.0-36 (mean: 17, median: 14) and 5.7-41 (mean: 11, median: 10) pg TEQ g(-1)lipid, respectively. The sums of the concentrations of 56 non-dioxin-like PCB congeners that were measured in the subjects' blood and breast milk were 43-445 (mean: 120, median: 106) and 34-366 (mean: 90, median: 81) ng g(-1)lipid, respectively, indicating that the total TEQ concentration and the total concentration of 56 non-dioxin-like PCB congeners in the maternal blood were notably higher than those in the breast milk. Statistically significant correlations were observed between maternal age and the total TEQ concentration of PCDDs, PCDFs, and dioxin-like PCBs or the total concentration of 56 non-dioxin-like PCB congeners in maternal blood, and significant correlations were also observed between maternal age and the total TEQ concentration of these dioxin-like compounds or the total concentration of 56 PCB congeners in breast milk. The total TEQ concentration of PCDDs, PCDFs, and dioxin-like PCBs in maternal blood showed a close correlation to that in subjects' breast milk, and there was also good correlation between the total concentration of 56 non-dioxin-like PCB congeners in maternal blood and that in subjects' breast milk. Pearson and Spearman correlation analyses showed a relationship between the total TEQ concentration of PCDDs, PCDFs, and dioxin-like PCBs and the total concentration of 56 non-dioxin-like PCB congeners in maternal blood, and also showed an association between the total TEQ concentration of these dioxin-like compounds and the total concentration of 56 PCB congeners in breast milk. The concentration of hexaCB-153 in maternal blood showed significant correlations to the total TEQ concentration of PCDDs, PCDFs, and dioxin-like PCBs or the total concentration of 56 non-dioxin-like PCBs in that sample. Moreover, the concentration of hexaCB-153 in breast milk also showed significant correlations to the total TEQ concentration of these dioxin-like compounds or the total concentration of 56 PCB congeners in that sample. These findings suggested that hexaCB-153 may be an indicator of total TEQ concentrations of PCDDs, PCDFs, and dioxin-like PCBs and total concentrations of 56 non-dioxin-like PCB congeners in blood and breast milk of primiparous mothers.
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Affiliation(s)
- Takashi Todaka
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan
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Abstract
Common environmental exposures may affect thyroid function in humans. Foetuses and infants are most vulnerable to these effects because they need thyroid hormone for normal neurodevelopment. Perchlorate, thiocyanate and nitrate are all competitive inhibitors of the sodium/iodine symporter (NIS) in pharmacologic doses, but their effects on human thyroid function at environmental exposure levels remain unclear. Many compounds, including polychlorinated biphenyls (PCBs), polybrominated diphenylethers (PBDEs), bisphenol-A (BPA) and triclosan, may have direct actions on the thyroid hormone receptor, but these effects are complex and are not yet well understood. Isoflavones inhibit thyroperoxidase (TPO) activity, and, therefore, may cause goitre and hypothyroidism if ingested at high levels, particularly in iodine-deficient individuals. Organochlorine pesticides and dioxins may decrease serum T(4) half-life by activating hepatic enzymes. Additional studies are needed to further elucidate the risk posed by these and other potentially thyroid-disrupting compounds.
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Affiliation(s)
- Elizabeth N Pearce
- Section of Endocrinology, Diabetes, and Nutrition, Boston University Medical Center, 88 East Newton street, Evans 201, Boston, MA 02118, USA.
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Abstract
PURPOSE OF REVIEW To overview the effects of endocrine disrupters on thyroid function. RECENT FINDINGS Studies in recent years have revealed thyroid-disrupting properties of many environmentally abundant chemicals. Of special concern is the exposure of pregnant women and infants, as thyroid disruption of the developing fetus may have deleterious effects on neurological outcome. Evidence is reviewed for the following groups of chemicals: polychlorinated biphenyls, dioxins, flame retardants, pesticides, perfluorinated chemicals, phthalates, bisphenol A and ultraviolet filters. Chemicals may exert thyroid effects through a variety of mechanisms of action, and some publications have focused on elucidating the mechanisms of specific (groups of) chemicals. SUMMARY A large variety of ubiquitous chemicals have been shown to have thyroid-disrupting properties, and the combination of mechanistic, epidemiological and exposure studies indicates that the ubiquitous human and environmental exposure to industrial chemicals may impose a serious threat to human and wildlife thyroid homeostasis. Currently, available evidence suggests that authorities need to regulate exposure to thyroid-disrupting chemicals of pregnant women, neonates and small children in order to avoid potential impairment of brain development. Future studies will indicate whether adults also are at risk of thyroid damage due to these chemicals.
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Affiliation(s)
- Malene Boas
- University Department of Growth and Reproduction, Rigshospitalet, Copenhagen, Denmark
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Chamie K, deVere White RW, Lee D, Ok J, Ellison LM. Agent Orange exposure, Vietnam War veterans, and the risk of prostate cancer. Cancer 2008; 113:2464-70. [DOI: 10.1002/cncr.23695] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Beischlag TV, Luis Morales J, Hollingshead BD, Perdew GH. The aryl hydrocarbon receptor complex and the control of gene expression. Crit Rev Eukaryot Gene Expr 2008; 18:207-50. [PMID: 18540824 DOI: 10.1615/critreveukargeneexpr.v18.i3.20] [Citation(s) in RCA: 530] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that controls the expression of a diverse set of genes. The toxicity of the potent AhR ligand 2,3,7,8-tetrachlorodibenzo-p-dioxin is almost exclusively mediated through this receptor. However, the key alterations in gene expression that mediate toxicity are poorly understood. It has been established through characterization of AhR-null mice that the AhR has a required physiological function, yet how endogenous mediators regulate this orphan receptor remains to be established. A picture as to how the AhR/ARNT heterodimer actually mediates gene transcription is starting to emerge. The AhR/ARNT complex can alter transcription both by binding to its cognate response element and through tethering to other transcription factors. In addition, many of the coregulatory proteins necessary for AhR-mediated transcription have been identified. Cross talk between the estrogen receptor and the AhR at the promoter of target genes appears to be an important mode of regulation. Inflammatory signaling pathways and the AhR also appear to be another important site of cross talk at the level of transcription. A major focus of this review is to highlight experimental efforts to characterize nonclassical mechanisms of AhR-mediated modulation of gene transcription.
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Affiliation(s)
- Timothy V Beischlag
- Center for Molecular Toxicology and Carcinogenesis, The Pennsylvania State University, University Park, PA 16802, USA
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Todaka T, Hirakawa H, Kajiwara J, Hori T, Tobiishi K, Onozuka D, Kato S, Sasaki S, Nakajima S, Saijo Y, Sata F, Kishi R, Iida T, Furue M. Concentrations of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and dioxin-like polychlorinated biphenyls in blood and breast milk collected from 60 mothers in Sapporo City, Japan. CHEMOSPHERE 2008; 72:1152-1158. [PMID: 18474391 DOI: 10.1016/j.chemosphere.2008.03.050] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 02/26/2008] [Accepted: 03/19/2008] [Indexed: 05/26/2023]
Abstract
We measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), non-ortho polychlorinated biphenyls (non-ortho PCBs), and mono-ortho polychlorinated biphenyls (mono-ortho PCBs) in paired samples of blood and breast milk collected from 60 mothers in Sapporo City, Hokkaido Prefecture, Japan. The present study is one of the few studies in which PCDDs, PCDFs, and dioxin-like PCBs have been measured in blood and breast milk collected from 60 same mothers. Of these 60 mothers, 30 were primipara (mean: 30.1 years, median: 28.0 years) and 30 were multipara (mean: 32.2 years, median: 32.5 years). The arithmetic mean TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of the primiparous mothers were 9.0, 3.3, 5.7, and 0.4 pg TEQ g(-1) lipid, respectively, and 5.2, 2.2, 4.5, and 0.4 pg TEQ g(-1) lipid, respectively, with the total TEQ concentrations of these dioxin-like compounds being 9.3-42.9 (mean: 18.4, median: 17.3) and 7.0-41.1 (mean: 12.3, median: 11.4) pg TEQ g(-1) lipid, respectively. In the case of multiparous mothers, the arithmetic mean TEQ concentrations of these dioxin-like compounds in blood and breast milk were 7.1, 2.7, 5.3, and 0.4 pg TEQ g(-1) lipid, respectively, and 3.9, 1.7, 3.8, and 0.4 pg TEQ g(-1) lipid, respectively, with the total TEQ concentrations being 3.4-28.1 (mean: 15.5, median: 13.9) and 2.7-20.0 (mean: 9.8, median: 9.2)pg TEQ g(-1) lipid, respectively. The total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk of primiparous mothers in Sapporo City appeared to be generally lower than those recently surveyed throughout the greater area of Japan. Significant correlations were observed between age and the total TEQ concentrations of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in the blood of primiparae and multiparae, and significant correlations were also observed between age and the total TEQ concentrations of these dioxin-like compounds in the breast milk of primiparae and multiparae. The total TEQ concentrations of PCDDs, PCDFs, and dioxin-like PCBs in the blood of primiparous mothers showed a close correlation to those in their breast milk and also showed good correlations between the total TEQ concentrations of these dioxin-like compounds in the blood of multiparous mothers and those in their breast milk. The result of a comparison of the arithmetic mean concentrations of each congener of PCDDs, PCDFs, non-ortho PCBs, and mono-ortho PCBs in blood and breast milk indicated that the transfer of octachlorodibenzo-p-dioxin (OCDD) from the blood to the breast milk was lower than those of other congeners. In contrast, among mono-ortho PCBs congeners, the arithmetic mean concentrations of 2,3',4,4',5-pentachlorobiphenyl (PentaCB) (#118) and 2,3,3',4,4'-PentaCB (#105) in the breast milk were slightly higher than those in the blood, which suggested that breast-fed infants may be at higher risk from mono-ortho PCBs.
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Affiliation(s)
- Takashi Todaka
- Department of Dermatology, Graduate School of Medical Sciences, Kyushu University, Maidashi 3-1-1, Fukuoka 812-8582, Japan.
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Foster WG, Agzarian J. Toward less confusing terminology in endocrine disruptor research. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2008; 11:152-161. [PMID: 18368550 DOI: 10.1080/00927870701873214] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The realization that environmental contaminants interact with hormone receptors and mimic or antagonize the actions of endogenous hormones led to introduction of terms such as endocrine disruptor, endocrine disrupter, hormonally active chemicals, and hormone mimics into the scientific and lay press. Reports suggesting a link between exposure to chemicals adversely affecting the endocrine system and (1) increasing rates of hormone-dependent cancers (breast, prostate, and testicular), (2) developmental detrimental effects in the male reproductive tract, (3) falling sperm counts, and (4) endometriosis resulted in an explosion of research, regulatory actions, and policy changes aimed at better understanding the hazards posed by these chemicals with subsequent restriction in their use. With increasing concern, there is worldwide action to develop testing strategies to allow for early identification of chemicals possessing endocrine disruptor activity. However, despite an expanding literature and numerous expert panel meetings, there continues to be controversy surrounding how to best define endocrine disruptors, resulting in (1) ambiguous use of the term, (2) confusion in the literature, and (3) publication of contentious lists of chemicals purported to be endocrine disruptors. Herein it is argued in favor of a more restrictive definition with adoption of a less ambiguous term, and in favor of development of a classification system to enhance more effective communication and facilitate appropriate allocation of limited resources in this highly charged area of toxicology.
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Affiliation(s)
- Warren G Foster
- Centre for Reproductive Care and Reproductive Biology Division, Department of Obstetrics and Gynecology, McMaster University, Hamilton, Ontario, Canada, L8N 3Z5.
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Yoshizawa K, Heatherly A, Malarkey DE, Walker NJ, Nyska A. A critical comparison of murine pathology and epidemiological data of TCDD, PCB126, and PeCDF. Toxicol Pathol 2007; 35:865-79. [PMID: 18098033 PMCID: PMC2623249 DOI: 10.1080/01926230701618516] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, or dioxin) and dioxin-like compounds (DLCs) induce numerous toxicities, including developmental, endocrine, immunological, and multi-organ carcinogenic, in animals and/or humans. Multiple studies completed by the National Toxicology Program (NTP) focused on the effects caused in Harlan Sprague-Dawley rats by specific DLCs, among them the prototypical dioxin, TCDD. Because humans are exposed daily to a combination of DLCs, primarily via ingestion of food, the Toxic Equivalency Factor (TEF) was developed in order to evaluate health hazards caused by these mixtures. Herein we review the pathological effects reported in humans exposed to TCDD; 3,3',4,4',5-pentachlorobiphenyl (PCB 126); and 2,3,4,7,8,-pentachlorodibenzofuran (PeCDF) and compare them to similar changes seen in NTP murine studies performed with the same compounds. While there were differences in specific pathologies observed, clear consistency in the target organs affected (liver, oral cavity, cardiovascular system, immune system, thyroid, pancreas, and lung) could be seen in both human studies and rodent toxicity and carcinogenicity investigations.
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Affiliation(s)
- Katsuhiko Yoshizawa
- Toxicologic Pathology, Drug Safety Research Laboratories, Astellas Pharma Inc., Yodogawa, Osaka, Japan
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Turyk ME, Anderson HA, Persky VW. Relationships of thyroid hormones with polychlorinated biphenyls, dioxins, furans, and DDE in adults. ENVIRONMENTAL HEALTH PERSPECTIVES 2007; 115:1197-203. [PMID: 17687447 PMCID: PMC1940071 DOI: 10.1289/ehp.10179] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Accepted: 05/30/2007] [Indexed: 05/16/2023]
Abstract
BACKGROUND Thyroid hormone homeostasis can be disrupted by exposure to ubiquitous and bioaccumulative organochlorines such as polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins (PCDDs). Whereas investigations of health effects have generally focused on human populations with relatively high exposures through occupation, accident, or high fish consumption, general population exposures may also carry risk. METHODS We studied associations of total thyroxine (T(4)) and thyroid-stimulating hormone (TSH) with PCBs, dioxin-like toxic equivalents (TEQs), and p,p'-diphenyldichloroethene (DDE) in adult participants without thyroid disease who participated in the 1999-2002 National Health and Nutrition Examination Survey, a cross-sectional survey examining a random sample representative of the U.S. population. RESULTS We found inverse associations of total T(4) with exposure to TEQs in both sexes, with stronger associations in females. In women, mean T(4) was 8.2 microg/dL, and levels were on average 0.75 microg/dL lower (95% confidence interval, 0.04-1.46) in women in the highest quintile of TEQ exposure compared with the lowest two quintiles. Effects were stronger in people > 60 years of age, with negative associations of T(4) with PCBs and TEQs, and positive associations of TSH with PCBs and TEQs in older women, and a negative association of TSH with PCBs in older men. CONCLUSIONS The data show a dose-dependent decrease in total T(4) with exposure to TEQs at levels similar to those found in the general U.S. population. The effects were stronger in women. The results suggest that older adults, who have a high risk of thyroid disease, may be more at risk for disruption of thyroid hormone homeostasis by dioxin-like organochlorines than younger adults.
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Affiliation(s)
- Mary E Turyk
- Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, Illinois 60612, USA.
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Pavuk M, Patterson DG, Turner WE, Needham LL, Ketchum NS. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (PCBs) in the serum of US Air Force veterans in 2002. CHEMOSPHERE 2007; 68:62-8. [PMID: 17280705 PMCID: PMC5124761 DOI: 10.1016/j.chemosphere.2006.12.039] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2006] [Revised: 12/07/2006] [Accepted: 12/11/2006] [Indexed: 05/13/2023]
Abstract
We measured levels of PCDDs, PCDFs, non-ortho, and mono-ortho substituted PCBs in 106 US Air Force Vietnam veterans, participants of the Air Force Health Study (AFHS) who attended the final medical examination in 2002. Twelve veterans were Ranch Hands involved in aerial spraying of herbicides in Vietnam (1962-1971), and 94 were Comparisons who flew transport missions in Southeast Asia (SEA) during the same time period. These veterans had no previous 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) measurement because they had not attended any of the previous AFHS examinations, or their previous measurements were missing or not valid. The mean TCDD levels in 2002 were 1.7 pg/g lipid in Comparisons and 5.5 pg/g lipid in Ranch Hands. The mean PCDD toxic equivalent - TEQ (1997) in Comparisons was 12.6 pg/g lipid, 5.4 pg/g lipid for PCDFs, 5.2 pg/g lipid for non-ortho PCBs, and 9.4 pg/g lipid for mono-ortho PCBs, with a total mean TEQ (1997) of 32.6 pg/g lipid. Corresponding mean TEQs in Ranch Hands were 15.5 pg/g lipid for PCDDs, 4.6 pg/g lipid for PCDFs, 2.2 pg/g lipid for non-ortho PCBs, and 9.3 pg/g lipid for mono-ortho PCBs, yielding the total mean TEQ (1997) of 31.6pg/g lipid. Using the re-evaluated 2005 WHO TEFs, the total mean TEQs (2005) decreased by about 28% in both Comparisons and Ranch Hands, to 23.6 pg/g lipid and 22.8 pg/g lipid, respectively. This was mainly due to changes of TEFs for the group of mono-ortho PCBs, which decreased the mono-ortho PCBs TEQs by almost 90% in both Ranch Hands and Comparisons.
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Affiliation(s)
- Marian Pavuk
- SpecPro Inc., 12500 San Pedro Avenue, Suite 670, San Antonio, TX 78216, USA.
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Gupta A, Gupta S, Pavuk M, Roehrborn CG. Anthropometric and metabolic factors and risk of benign prostatic hyperplasia: a prospective cohort study of Air Force veterans. Urology 2007; 68:1198-205. [PMID: 17169643 DOI: 10.1016/j.urology.2006.09.034] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Revised: 09/03/2006] [Accepted: 09/14/2006] [Indexed: 10/23/2022]
Abstract
OBJECTIVES The relationship between anthropometric and metabolic factors and benign prostatic hyperplasia (BPH) is poorly understood. We investigated the associations of BPH with anthropometric and metabolic parameters in this prospective study of Vietnam War veterans. METHODS A total of 1206 participants in the comparison arm of the Air Force Health Study with a median follow-up of 15.6 years were included in this study. The "Ranch Hand" group, occupationally exposed to herbicides, was excluded to eliminate any confounding from exposure to herbicides. BPH was determined by medical record review using the International Classification of Diseases and Related Problems, Ninth Revision. We used Cox proportional hazards regression models for the statistical analysis. RESULTS The median age for BPH diagnosis was 58.6 years. On multivariate analyses, increasing age (relative risk [RR] 1.14, 95% confidence interval [CI] 1.12 to 1.17), height (RR 1.02, 95% CI 1.004 to 1.03), and fasting blood glucose (RR 1.004, 95% CI 1.001 to 1.007) were associated with increased risk. The effect of age varied with the duration of follow-up. A greater systolic blood pressure (RR 0.992, 95% CI 0.986 to 0.997) was associated with decreased risk of BPH. A dose-response effect was seen for age, height, and systolic blood pressure. No effect was seen for weight, body mass index, change in weight or body mass index, lipids, thyroid hormone status, or the metabolic syndrome. CONCLUSIONS The risk of BPH increased with increasing age, height, and fasting blood glucose levels. The risk was decreased with a greater systolic blood pressure. No relationship was seen between BPH and metabolic syndrome, weight, body mass index, lipid level, or thyroid hormone status.
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Affiliation(s)
- Amit Gupta
- Department of Urology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9110, USA
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50
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Turyk ME, Anderson HA, Freels S, Chatterton R, Needham LL, Patterson DG, Steenport DN, Knobeloch L, Imm P, Persky VW. Associations of organochlorines with endogenous hormones in male Great Lakes fish consumers and nonconsumers. ENVIRONMENTAL RESEARCH 2006; 102:299-307. [PMID: 16563369 DOI: 10.1016/j.envres.2006.01.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2005] [Revised: 01/13/2006] [Accepted: 01/25/2006] [Indexed: 05/08/2023]
Abstract
This study investigated the relationships of steroid and thyroid hormones with total noncoplanar polychlorinated biphenyls (PCBs), total toxic equivalents (TEQs) from dioxins-like organochlorines, and dichlorodiphenyl dichloroethene (DDE) in 56 male frequent and infrequent Great Lakes sport caught fish consumers. Significant negative associations were found for triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH), and sex hormone binding globulin (SHBG)-bound testosterone with PCBs, for TSH with total TEQs, and for estrone sulfate with DDE, adjusting for age, body mass index, and medication use. Follicle-stimulating hormone, luteinizing hormone, free testosterone, and SHBG were not significantly associated with organochlorines. Models that accounted for exposure to both PCBs and TEQs predicted T4, estrone sulfate, and SHBG-bound testosterone better than models that included either PCBs or TEQs alone, with the lowest hormone levels occurring in the participants with both higher PCB levels and lower TEQ levels. These data suggest that exposure to PCBs, dioxin-like organochlorines, and DDE, alone and potentially in combination, may be associated with effects on the endocrine system in adult males. Further studies should help delineate specific exposure effects and effects of exposures to other common environmental contaminants alone and in combination with PCBs.
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Affiliation(s)
- Mary E Turyk
- Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, 1603 W. Taylor Street, Room 879, (M/C 923), Chicago, IL 60612, USA.
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