Éditeur(s) : HAL CCSD American Chemical Society
Résumé : International audience
2-Amino-9H-pyrido[2,3-b]indole (AalphaC) is the most abundant carcinogenic heterocyclic aromatic amine (HAA) formed in mainstream tobacco smoke. AalphaC is a liver carcinogen in rodents, but its carcinogenic potential in humans is not known. To obtain a better understanding of the genotoxicity of AalphaC in humans, we have investigated its metabolism and its ability to form DNA adducts in human hepatocytes. Primary human hepatocytes were treated with AalphaC at doses ranging from 0.1-50 muM, and the metabolites were characterized by ultra-performance LC/ion trap multistage mass spectrometry (UPLC/MSn). Six major metabolites were identified: a ring-oxidized doubly conjugated metabolite, N2-acetyl-2-amino-9H-pyrido[2,3-b]indole-6-yl-oxo-(beta-d-glucuronic acid) (N2-acetyl-AalphaC-6-O-Gluc); two ring-oxidized glucuronide (Gluc) conjugates: 2-amino-9H-pyrido[2,3-b]indol-3-yl-oxo-(beta-d-glucuronic acid) (AalphaC-3-O-Gluc) and 2-amino-9H-pyrido[2,3-b]indol-6-yl-oxo-(beta-d-glucuronic acid) (AalphaC-6-O-Gluc); two sulfate conjugates, 2-amino-9H-pyrido[2,3-b]indol-3-yl sulfate (AalphaC-3-O-SO3H) and 2-amino-9H-pyrido[2,3-b]indol-6-yl sulfate (AalphaC-6-O-SO3H); and the Gluc conjugate, N2-(beta-d-glucosidurony1)-2-amino-9H-pyrido[2,3-b]indole (AalphaC-N2-Gluc). In addition, four minor metabolites were identified: N2-acetyl-9H-pyrido[2,3-b]indol-3-yl sulfate (N2-acetyl-AalphaC-3-O-SO3H), N2-acetyl-9H-pyrido[2,3-b]indol-6-yl sulfate (N2-acetyl-AalphaC-6-O-SO3H), N2-acetyl-2-amino-9H-pyrido[2,3-b]indol-3-yl-oxo-(beta-d-glucuronic acid) (N2-acetyl-AalphaC-3-O-Gluc), and O-(beta-d-glucosidurony1)-2-hydroxyamino-9H-pyrido[2,3-b]indole (AalphaC-HN2-O-Gluc). The latter metabolite, AalphaC-HN2-O-Gluc is a reactive intermediate that binds to DNA to form the covalent adduct N-(2'-deoxyguanosin-8-yl)-2-amino-9H-pyrido[2,3-b]indole (dG-C8-AalphaC). Preincubation of hepatocytes with furafylline, a selective mechanism-based inhibitor of P450 1A2, resulted in a strong decrease in the formation of AalphaC-HN2-O-Gluc and a concomitant decrease in DNA adduct formation. Our findings describe the major pathways of metabolism of AalphaC in primary human hepatocytes and reveal the importance of N-acetylation and glucuronidation in metabolism of AalphaC. P450 1A2 is a major isoform involved in the bioactivation of AalphaC to form the reactive AalphaC-HN2-O-Gluc conjugate and AalphaC-DNA adducts.
ISSN: 0893-228X

anses-01419468
https://hal-anses.archives-ouvertes.fr/anses-01419468
https://hal-anses.archives-ouvertes.fr/anses-01419468/document
https://hal-anses.archives-ouvertes.fr/anses-01419468/file/Bellamri%20et%20al.%20-%202016%20-%20Metabolism%20of%20the%20Tobacco%20Carcinogen%202-Amino-9H-py.pdf
DOI : 10.1021/acs.chemrestox.6b00394

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Different household insecticide applications via two electric vaporizers emitting transfluthrin were realized in a full-scale experimental room under controlled air exchange rate conditions. On-line high-time resolved measurements of the gas-phase concentrations of the active substance during and immediately after the spreading periods were performed with a High Sensitivity Proton-Transfer-Reaction Mass Spectrometer (HS-PTR-MS). Experimental and modelled data from the ConsExpo 4.0 software were also compared to evaluate the sources of differences. Different application scenarios were also compared. Averaged inhaled concentrations over 1h, 1week, and 5months were estimated to be 8.3, 1.8, and 1.8μg.m(-3), respectively. Corresponding margins of exposures range from 1000 to 10,000, claiming for the absence of effect. Dermal and dust ingestion pathways, although roughly estimated, seems being non-negligible. This claims for a more in-depth integrated risk assessment.
ISSN: 0160-4120

hal-00875320
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00875320
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00875320/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00875320/file/Transfluthrin-indoor-accepted.pdf
DOI : 10.1016/j.envint.2013.07.011

Éditeur(s) : HAL CCSD American Chemical Society
Résumé : International audience
Aromatic amines and structurally related heterocyclic aromatic amines (HAAs) are produced during the combustion of tobacco or during the high-temperature cooking of meat. Exposure to some of these chemicals may contribute to the etiology of several common types of human cancers. 2-Amino-9H-pyrido[2,3-b]indole (AαC) is the most abundant HAA formed in mainstream tobacco smoke: it arises in amounts that are 25-100 times greater than the levels of the arylamine, 4-aminobiphenyl (4-ABP), a human carcinogen. 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is a prevalent HAA formed in cooked meats. AαC and MeIQx are rodent carcinogens; however, their carcinogenic potency in humans is unknown. A preliminary assessment of the carcinogenic potential of these HAAs in humans was conducted by examining the capacity of primary human hepatocytes to form DNA adducts of AαC and MeIQx, in comparison to 4-ABP, followed by the kinetics of DNA adduct removal by cellular enzyme repair systems. The principal DNA adducts formed were N-(deoxyguanosin-8-yl) (dG-C8) adducts. Comparable levels of DNA adducts were formed with AαC and 4-ABP, whereas adduct formation was ∼5-fold lower for MeIQx. dG-C8-AαC and dG-C8-4-ABP were formed at comparable levels in a concentration-dependent manner in human hepatocytes treated with procarcinogens over a 10,000-fold concentration range (1 nM-10 μM). Pretreatment of hepatocytes with furafylline, a selective inhibitor of cytochrome P450 1A2, resulted in a strong diminution of DNA adducts signifying that P450 1A2 is a major P450 isoform involved in bioactivation of these procarcinogens. The kinetics of adduct removal varied for each hepatocyte donor. Approximately half of the DNA adducts were removed within 24 h of treatment; however, the remaining lesions persisted over 5 days. The high levels of AαC present in tobacco smoke and its propensity to form persistent DNA adducts in human hepatocytes suggest that AαC can contribute to DNA damage and the risk of hepatocellular cancer in smokers.
ISSN: 0893-228X

inserm-00869907
http://www.hal.inserm.fr/inserm-00869907
DOI : 10.1021/tx4002226
PUBMED : 23898916

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Dietary exposure to pesticide residues may present a risk to public health, especially for sensitive populations such as pregnant women. To characterize this risk, this study assessed chronic dietary exposure to pesticide residues based on the French ELFE cohort. A self-administered food frequency questionnaire (FFQ) about the last three months of pregnancy filled in by pregnant women in 2011 was used in combination with occurrence data from French Total Diet Studies completed by the results of national monitoring programs on pesticide residues in food. The dietary intake of pesticides (μg/kg of body weight/day) was estimated for 14,099 pregnant women with a complete FFQ, for 317 substances under two occurrence scenarios to handle left-censored data: a lower-bound scenario (LB), where undetected results were set to zero, and an upper-bound scenario (UB), where undetected results were set to the detection limit if the substance was expected to be found in food and zero if it was not. The risk was assessed for 284 substances with a toxicological reference value (TRV) and a good coverage level of the diet potentially contributing to pesticide intake. The cumulative risk was also assessed for seven effects on nervous and thyroid systems using the hazard index and the Cumulative Assessment Groups defined by EFSA. Substances with the highest exposure levels under the LB scenario were, in decreasing order, imazalil, piperonyl butoxide, chlorpropham, thiabendazole, iprodione and propargite. Under the LB scenario, only for lindane did women have a statistically significant probability of exceeding the TRV (2.4%). Under the UB scenario, risk could not be excluded for nine other substances. A better management of left-censored data and more sensitive analyses of the main food contributors might help to refine the UB exposure and risk assessments. A statistically significant cumulative risk was found for neurochemical effects related to high intake levels of three organophosphate insecticides (chlorpyrifos, pirimiphos-methyl and dimethoate) mainly detected in fruits and cereals
ISSN: 0160-4120

hal-01319892
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01319892
DOI : 10.1016/j.envint.2016.04.007
PUBMED : 27187793

Éditeur(s) : Oxford Univ Press
Résumé : Biological reference points are important tools for fisheries management. Reference points are not static, butmay change when a population's environment or the population itself changes. Fisheries-induced evolution is one mechanism that can alter population characteristics, leading to "shifting" reference points by modifying the underlying biological processes or by changing the perception of a fishery system. The former causes changes in "true" reference points, whereas the latter is caused by changes in the yardsticks used to quantify a system's status. Unaccounted shifts of either kind imply that reference points gradually lose their intended meaning. This can lead to increased precaution, which is safe, but potentially costly. Shifts can also occur in more perilous directions, such that actual risks are greater than anticipated. Our qualitative analysis suggests that all commonly used reference points are susceptible to shifting through fisheries-induced evolution, including the limit and "precautionary" reference points for spawning-stock biomass, B-lim and B-pa, and the target reference point for fishing mortality, F-0.1. Our findings call for increased awareness of fisheries-induced changes and highlight the value of always basing reference points on adequately updated information, to capture all changes in the biological processes that drive fish population dynamics.
Ices Journal Of Marine Science (1054-3139) (Oxford Univ Press), 2013-07 , Vol. 70 , N. 4 , P. 707-721

Droits : 2013 International Council for the Exploration of the Sea. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com
http://archimer.ifremer.fr/doc/00151/26228/24302.pdf
DOI:10.1093/icesjms/fst077
http://archimer.ifremer.fr/doc/00151/26228/

Éditeur(s) : HAL CCSD Society of Environmental Toxicology and Chemistry Press (SETAC)
Résumé : International audience
Tributyltin (TBT) and triphenyltin (TPT) are emblematic endocrine disruptors, which have been mostly studied in gonochoric prosobranchs. Although both compounds can simultaneously occur in the environment, they have mainly been tested separately for their effects on snail reproduction. Because large discrepancies in experimental conditions occurred in these tests, the present study aimed to compare the relative toxicity of TBT and TPT under similar laboratory conditions in the range of 0 ng Sn/L to 600 ng Sn/L. Tests were performed on the simultaneous hermaphrodite Lymnaea stagnalis, a freshwater snail in which effects of TPT were unknown. Survival, shell length, and reproduction were monitored in a 21-d semistatic test. Frequency of abnormal eggs was assessed as an additional endpoint. Triphenyltin hampered survival while TBT did not. Major effects on shell solidity and reproduction were observed for both compounds, reproductive outputs being more severely hampered by TBT than by TPT. Considering the frequency of abnormal eggs allowed increasing test sensitivity, because snail responses to TBT could be detected at concentrations as low as 19 ng Sn/L. However, the putative mode of action of the 2 compounds could not be deduced from the structure of the molecules or from the response of apical endpoints. Sensitivity of L. stagnalis to TBT and TPT was compared with the sensitivity of prosobranch mollusks with different habitats and different reproductive strategies.
Environmental Toxicology and Chemistry

hal-00877955
https://hal.archives-ouvertes.fr/hal-00877955
DOI : 10.1002/etc.2200
PUBMED : 23450754

Éditeur(s) : HAL CCSD Elsevier Masson
Résumé : National audience
Contexte La qualité de l’air ambiant dans les enceintes de transports ferroviaires souterrains (EFS) est caractérisée par des particules en suspension riches en métaux, majoritairement du fer, et en carbone, dont la concentration massique est très supérieure à celle mesurée dans l’air ambiant extérieur aux EFS. Cependant, les risques sanitaires chez les travailleurs des EFS liés aux polluants chimiques de l’air présents dans ces enceintes ferroviaires ont été peu étudiés. Dans ce contexte, l’Anses a été saisie afin de dresser un état des connaissances et réaliser une évaluation des risques sanitaires (ERS) chez les travailleurs des EFS. Méthodes Un groupe de travail pluridisciplinaire a analysé les études publiées jusqu’en décembre 2014 et des données communiquées par les exploitants de transport. L’ERS a porté sur les travailleurs de l’exploitation, l’organisation du transport et des services, et des commerces qui exercent une activité durant les horaires de trafic des rames de voyageurs. L’exposition chronique des travailleurs a été estimée à partir des données de concentration inhalée en particules (PM2,5 et PM10), en éléments métalliques, en carbone, en hydrocarbures aromatiques polycycliques particulaires et en hydrocarbures aromatiques monocycliques, issues d’une campagne transversale de métrologie individuelle de la RATP. Cette exposition estimée a ensuite été comparée à une valeur toxicologique de référence (VTR ajustée, VLEP, NOAECHEC) pour calculer un indicateur de risque. Résultats Les risques sanitaires en lien avec les éléments métalliques évalués individuellement semblent négligeables. Concernant l’exposition chronique aux particules, une inflammation des voies respiratoires et des effets consécutifs à cette inflammation sont probables, sur la base d’un effet démontré par une étude de toxicité aiguë chez l’animal. Par analogie avec les particules de l’air ambiant extérieur, des effets délétères sont attendus sur la santé cardiovasculaire et respiratoire en lien avec l’exposition chronique de ces travailleurs aux particules des EFS. L’ERS présente néanmoins des incertitudes notables compte tenu notamment du corpus d’études épidémiologiques assez peu informatif et de l’absence d’étude toxicologique d’exposition chronique. Conclusion Des effets sanitaires sont attendus en relation avec l’exposition chronique des travailleurs à la pollution de l’air des EFS. Des travaux sont recommandés pour combler les lacunes des connaissances sur la toxicité à long terme des particules de l’air de ces enceintes ferroviaires, mais également sur l’exposition de certaines catégories de travailleurs de la maintenance vraisemblablement plus exposés
ISSN: 1775-8785

hal-01331986
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01331986
DOI : 10.1016/j.admp.2016.03.448
PUBMED : 26334607

Éditeur(s) : HAL CCSD American Chemical Society
Résumé : International audience
2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), a carcinogenic heterocyclic aromatic amine formed in cooked meats, is metabolically activated to electrophilic intermediates that form covalent adducts with DNA and protein. We previously identified an adduct of PhIP formed at the Cys34 residue of human serum albumin following reaction of albumin with the genotoxic metabolite 2-hydroxyamino-1-methyl-6-phenylimidazo[4,5-b]pyridine (HONH-PhIP). The major adducted peptide recovered from a tryptic/chymotryptic digest was identified as the missed-cleavage peptide LQQC*[SO2PhIP]PFEDHVK, a [cysteine-S-yl-PhIP]-S-dioxide linked adduct. In this investigation, we have characterized the albumin adduction products of N-sulfooxy-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (N-sulfooxy-PhIP), which is thought to be a major genotoxic metabolite of PhIP formed in vivo. Targeted and data-dependent scanning methods showed that N-sulfooxy-PhIP adducted to the Cys34 of albumin in human plasma to form LQQC*[SO2PhIP]PFEDHVK at levels that were 8-10-fold greater than the adduct levels formed with N-(acetyloxy)-2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (N-acetoxy-PhIP) or HONH-PhIP. We also discovered that N-sulfooxy-PhIP forms an adduct at the sole tryptophan (Trp214) residue of albumin in the sequence AW*[PhIP]AVAR. However, stable adducts of PhIP with albumin were not detected in human hepatocytes. Instead, PhIP and 2-amino-1-methyl-6-(5-hydroxy)phenylimidazo[4,5-b]pyridine (5-HO-PhIP), a solvolysis product of the proposed nitrenium ion of PhIP, were recovered during the proteolysis, suggesting a labile sulfenamide linkage had formed between an N-oxidized intermediate of PhIP and Cys34 of albumin. A stable adduct was formed at the Tyr411 residue of albumin in hepatocytes and identified as a deaminated product of PhIP, Y*[desaminoPhIP]TK, where the 4-HO-tyrosine group bound to the C-2 imidazole atom of PhIP.
ISSN: 0893-228X

hal-01146777
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01146777
DOI : 10.1021/acs.chemrestox.5b00075
PUBMED : 25815793

Éditeur(s) : HAL CCSD John Libbey Eurotext
Résumé : International audience
Environmental health risk assessment is commonly used in France for risk management purposes. The Methodology section of the "Société française de santé environnement" (French Society for Environmental Health) seeks to improve the utility and implementation of risk assessment in France. An initial operational objective is to make a list of short-, intermediate- and long-term improvements. This inventory is based in part on the experience and expertise of society members in this area and in part on their analysis of "Science and Decisions: Advancing Risk Assessment" (National Research Council 2009). In this paper, the Society recommends modifications in the indications for and use of risk assessments, during each of the four stages of the process: hazard identification and dose-response assessment, exposure assessment, risk characterization, and results interpretation. Some may be implemented now, while others need consensus building or research because of gaps in knowledge. Environmental health risk assessment must be understood as a decision tool for risk management in situations of uncertainly. Thus, appropriate linkage is required between decision making and assessment, and between the methods and the expected results.
L'évaluation des risques sanitaires est fréquemment utilisée en France dans les processus de décision en santé environnementale. La section " Méthodologie d'évaluation des risques sanitaires " de la Société française de santé environnement (SFSE) s'est donnée pour objectif de proposer des éléments de réflexion et des outils méthodologiques en vue d'améliorer l'utilité et les pratiques de l'évaluation des risques sanitaires. Un premier objectif opérationnel est l'inventaire des améliorations possibles à court, moyen et long termes à apporter à la démarche et à son utilisation. Ce travail s'est fondé, d'une part, sur la pratique et l'expertise des membres de la section, et, d'autre part, sur une lecture critique du rapport " Science and Decisions : Advancing Risk Assessment " publié en 2009 par le National Research Council et portant également sur les évolutions de la démarche. Dans cet article, la section restitue les conclusions de cet inventaire critique et propose un certain nombre d'améliorations en termes d'indications et d'utilisations de l'évaluation des risques sanitaires pour chacune des quatre étapes : identification des dangers et relation dose-réponse ; évaluation de l'exposition ; caractérisation des risques ; et interprétation des résultats. Certaines recommandations peuvent être mises en oeuvre immédiatement ; d'autres, en préalable à leur mise en oeuvre, nécessitent un consensus ou encore de la recherche car les connaissances manquent. En conclusion, la section insiste sur le fait que l'évaluation des risques sanitaires doit être comprise comme une aide à la décision en situation d'incertitude ; l'articulation entre le contexte décisionnel et l'évaluation, sa méthodologie et les résultats attendus est donc primordiale.
ISSN: 1635-0421

ineris-00963325
https://hal-ineris.archives-ouvertes.fr/ineris-00963325
DOI : 10.1684/ers.2011.0435
INERIS : EN-2012-016

Éditeur(s) : HAL CCSD John Libbey Eurotext
Résumé : International audience
Chemical risk assessment is a tool used in decision-making processes concerning situations of scientific uncertainty. Approaches to risk assessment in occupational and environmental health share the same objective of risk prevention. Nevertheless, the methods for both differ depending on whether the goal is to enforce regulations or conduct expert assessments and studies. These differences are stronger in occupational health, for which regulations require risk assessments at the work station, to classify and prioritize exposure situations to implement occupational risk prevention strategies. Risk assessment thus has somewhat different meanings in occupational and environmental health. This article attempts to clarify the different terms used in the different contexts and to describe the similarities and differences of the two approaches.
ISSN: 1635-0421

hal-00936256
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00936256
DOI : 10.1684/ers.2013.0646

Éditeur(s) : HAL CCSD John Libbey Eurotext
Résumé : International audience
French toxicological reference values (VTR) and French occupational exposure limit values (VLEP) are indicators that are widely used in risk assessment for, respectively, human and occupational health. Neither value can replace the other. However, the information obtained for one can be very useful for the other. We propose to clarify the fundamental differences and similarities between these two values. To achieve this, we review first their history and then the methods used to derive them; we conclude by proposing some improvements to harmonize them. A case study of formaldehyde illustrates our analysis.
ISSN: 1635-0421

hal-00936267
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00936267
DOI : 10.1684/ers.2013.0647

Éditeur(s) : HAL CCSD AACR
Résumé : International audience
Cancer Research
Chicago, United States

hal-01118498
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118498
DOI : 10.1158/1538-7445.AM2012-5739

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (B[a]P), are widely distributed environmental contaminants exerting toxic effects such as genotoxicity and carcinogenicity, mainly associated with aryl hydrocarbon receptor (AhR) activation and the subsequent induction of cytochromes P-450 (CYP) 1-metabolizing enzymes. We previously reported an up-regulation of AhR expression and activity in primary cultures of human T lymphocyte by a physiological activation. Despite the suggested link between exposure to PAHs and the risk of lymphoma, the potential of activated human T lymphocytes to metabolize AhR exogenous ligands such as B[a]P, and produce DNA damage has not been investigated. In the present study, we characterized the genotoxic response of primary activated T lymphocytes to B[a] P. We demonstrated that, following T lymphocyte activation, B[a]P treatment triggers a marked increase in CYP1 expression and activity generating, upon metabolic activation, DNA adducts and double-strand breaks (DSBs) after a 48-h treatment. At this time point, B[a]P also induces a DNA damage response with ataxia telangiectasia mutated kinase activation, thus producing a p53-dependent response and T lymphocyte survival. B[a]P activates DSB repair by mobilizing homologous recombination machinery but also induces gene mutations in activated human T lymphocytes which could consequently drive a cancer process. In conclusion, primary cultures of activated human T lymphocytes represent a good model for studying genotoxic effects of environmental contaminants such as PAHs, and predicting human health issues.
ISSN: 0006-2952

hal-01560145
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560145
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560145/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01560145/file/Liamin%20et%20al.%20-%20Benzo%5Ba%5Dpyrene-induced%20DNA%20damage%20associated%20with%20.pdf
DOI : 10.1016/j.bcp.2017.04.025

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Cyanobacteria and their toxins are known as a health hazard in recreative and distributed waters. Monitoring data from 2004 to 2011 were collected at regional scale to characterize exposition parameters to microcystins in Brittany (Western France). The data show that cyanobacteria populations are experiencing a composition shift leading to a longer duration of cell densities higher than WHO alert levels 2 and 3. Microcystins however appear to be more frequently detected with subacute concentrations in low cell density samples than in high cell density samples or during bloom episodes. Positive relations are described between microcystin concentrations, detection frequencies and cyanobacteria biovolumes, allowing for a novel definition of alert levels and decision framework following WHO recommendations
ISSN: 1438-4639

hal-01255825
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01255825
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01255825/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01255825/file/Improving%20microcystin%20monitoring%20relevance%20in%20recreative%20waters%20A%20regional%20case-study%20%28Brittany%2C%20Western%20France%2C%20Europe%29.pdf
DOI : 10.1016/j.ijheh.2015.12.004

Éditeur(s) : HAL CCSD
Résumé : International audience
Human polycystic echinococcosis is a parasitic infection caused by the larval stage of Echinococcus vogeli which occurs in rural areas of Central and South America. Abdominal echinococcosis caused by E. vogeli is reported for the first time in a child, a 6-year-old boy in French Guiana. The diagnosis was made by histological and molecular techniques. In tropical regions, this neglected disease must be considered even in children.
ISSN: 2046-9047

hal-01484299
https://hal.univ-lorraine.fr/hal-01484299
DOI : 10.1179/2046905515Y.0000000054

Éditeur(s) : HAL CCSD Taylor & Francis
Résumé : International audience
o abstract
ISSN: 0360-2532

hal-01485263
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01485263

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Heterocyclic aromatic amines (HAA) are formed in cooked meat, poultry and fish but also arise in tobacco smoke and exhaust gases. HAA are potential human carcinogens, which require metabolic activation to exert their genotoxicity. Human tissues can bioactivate HAA to produce reactive intermediates that bind to DNA. HAA DNA adduct formation occurs in human hepatocytes; however, the potential of HAA to form DNA adducts has not been investigated in human T lymphocytes. In this study, we investigated the ability of human T lymphocytes activated with PMA/Ionomycin or CD3/CD28 to express functional CYP1 activity and bioactivate three major HAA: 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), and 2-amino-9H-pyrido[2,3-b]indole (AαC) to form DNA adducts. Adducts were measured by ultraperformance liquid chromatography-electrospray ionization/multistage scan mass spectrometry. The highest level of DNA adducts occurred for AαC (16 adducts per 109 nucleotides), followed by PhIP (9 adducts per 109 nucleotides). In contrast, DNA adducts formed from MeIQx and the structurally related aromatic amine 4-aminobiphenyl, a known human carcinogen, were below the limit of detection (< 3 adducts per 109 nucleotides). Moreover, we demonstrate that AαC is a potent inducer of CYP1A1 and CYP1B1 activity through a transcriptional mechanism involving the AhR pathway. Overall, our results highlight the capacity of activated human T lymphocytes to more efficiently bioactivate AαC to form DNA adducts than other prominent HAA or 4-ABP. Environ. Mol. Mutagen. 57:656-667, 2016.
ISSN: 0893-6692

hal-01400486
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01400486
DOI : 10.1002/em.22059
PUBMED : 27801952

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Sixty-six semi-volatile organic compounds (SVOCs)—phthalates, polybrominated diphenyl ethers (PBDEs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), one pyrethroid, organochlorine and organophosphorous pesticides, alkylphenols, synthetic musks, tri-n-butylphosphate and triclosan—were measured on PM10 filters collected over 7 days during a nationwide survey of 285 French dwellings, representative of nearly 25 million housing units. Thirty-five compounds were detected in more than half of the dwellings. PAHs, phthalates and triclosan were the major particle-bound SVOCs, with a median concentration greater than 1 ng m−3 for butylbenzyl phthalate (BBP) (median: 1.6 ng m−3), di(2-ethylhexyl) phthalate (DEHP) (46 ng m−3) and di-iso-nonyl phthalate (DiNP) (7.9 ng m−3), and greater than 0.1 ng m−3 for triclosan (114 pg m−3), benzo(a)anthracene (44.4 pg m−3), benzo(a)pyrene (138 pg m−3), benzo(b)fluoranthene (306 pg m−3), benzo(g,h,i)perylene (229 pg m−3), and indeno(1,2,3-c,d)pyrene (178 pg m−3). For most of the SVOCs, higher concentrations were found in the dwellings of smokers and during the heating season. The concentrations of banned SVOCs—namely, PCBs and organochlorine pesticides—were correlated. Permethrin, 4-tert-butylphenol and bisphenol-A showed no correlation with the other SVOCs and seemed to have their own specific sources. Most SVOCs were positively associated with PM10 concentration, suggesting that any factor that raises the mass of indoor airborne particles also increases the exposure to SVOCs through inhalation
ISSN: 1352-2310

hal-01304354
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01304354
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01304354/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01304354/file/Semi-volatile%20organic%20compounds.pdf
DOI : 10.1016/j.atmosenv.2016.04.016

Éditeur(s) : HAL CCSD
Résumé : International audience
Toxicology Letters
Paris, France

hal-01127980
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01127980
DOI : 10.1016/j.toxlet.2011.05.152

Éditeur(s) : HAL CCSD Institute of Electrical and Electronics Engineers
Résumé : International audience
An effective solution for increasing the exposure uniformity and efficiency of biological samples in in vitro bioelectromagnetic experiments at 60 GHz is proposed by introducing a novel choke ring antenna (CRA). The CRA is optimized to provide a uniform exposure of samples, whose dimensions are equivalent to those of a standard 35-mm Petri dish, positioned close to the antenna aperture, i.e., 10-20 wavelengths. The antenna prototype is fabricated in metallized foam. The realized exposure efficiency of the sample exceeds 55% (if estimated for an exposure uniformity better than - 0.5 dB). To validate the numerical results, the field intensity profiles on the surface of a high-water-content phantom have been experimentally obtained using a high-resolution infrared camera. Compared to the standard open-ended waveguide and horn antennas, typically used for millimeter-wave dosimetry, a twofold advantage of the proposed CRA is demonstrated, namely, the improvement of the exposure efficiency by a factor of 1.5 to 2 with a simultaneous reduction of the exposure distance by a factor of 8-2, respectively, depending on the type of the reference antenna. These advantages make the proposed CRA an excellent candidate for 60-GHz short-range exposure systems for in vitro bioelectromagnetic studies.
ISSN: 0018-9480

hal-00874349
https://hal.archives-ouvertes.fr/hal-00874349
DOI : 10.1109/TMTT.2013.2255619