References of "Thomé, Jean-Pierre"
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See detailInvestigating apical adverse effects of four endocrine active substances in the freshwater gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Lagadic, Laurent; Barsi, Alpar et al

in Science of the Total Environment (2014), 493

The hermaphroditic gastropod Lymnaea stagnalis is proposed as a candidate species for the development of OECD guidelines for testing of the reprotoxicity of chemicals, including endocrine active ... [more ▼]

The hermaphroditic gastropod Lymnaea stagnalis is proposed as a candidate species for the development of OECD guidelines for testing of the reprotoxicity of chemicals, including endocrine active substances (EASs). Up to now, only a few putative EASs have been tested for their reproductive toxicity in this species. In this study, we investigate the effects of four EASs with different affinities to the vertebrate estrogen and androgen receptors (chlordecone as an estrogen; cyproterone acetate, fenitrothion and vinclozolin as anti-androgens) on the reproduction of L. stagnalis in a 21-day semi-static test. Testosterone and 17α-ethinylestradiol (EE2) were used as the reference compounds. The tested EASs had no significant effect on growth and survival at the tested concentration ranges (ng to μg/L). Classical reproduction endpoints (i.e., oviposition and fecundity) were not responsive to the tested chemicals, except for chlordecone and 17α-ethinylestradiol, which hampered reproduction from 19.6 μg/L and 17.6 μg/L, respectively. The frequency of polyembryonic eggs, used as an additional endpoint, demonstrated the effects of all compounds except EE2. The molecular pathways, which are involved in such reproduction impairments, remain unknown. Our results suggest that egg quality is a more sensitive endpoint as compared to other reproductive endpoints commonly assessed in mollusk toxicity tests. [less ▲]

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See detailMoult-related changes in the integument, midgut, and digestive gland in the freshwater amphipod gammarus pulex
Trevisan, Mélissa ULg; Leroy, Delphine; Decloux, Nicole ULg et al

in Journal of Crustacean Biology (2014), 34(5), 539-551

On the basis of macroscopic aspects (body and eye colour, lipid droplets), it was possible to sort specimens of Gammarus pulex (Linnaeus, 1758) into five categories that correspond to moult periods and ... [more ▼]

On the basis of macroscopic aspects (body and eye colour, lipid droplets), it was possible to sort specimens of Gammarus pulex (Linnaeus, 1758) into five categories that correspond to moult periods and stages (A, B, C, D1 and D2) based on integument features (tergite cuticle stiffness, layers and thickness). These stages also correspond to changes in digestive tract histology (gut content, cell ultrastructure, and lipid storage). With reference to the pereion tergite integument, this makes it possible to standardize moulting stage terminology and criteria with those applied to decapods while validating a quick, simple, moult-staging method that avoids injury and informs us about the physiology of the whole organism. The moult cycle was very short (about 12-15 days), with a "virtual," practically non-existent, anecdysis or "integument resting period" between post-ecdysis and pre-ecdysis. The pore canals previously known to be "open to the outside" appeared closed at early post-ecdysis by a lipid-rich fillng material that could be responsible for the cuticular waterproofing barrier allowing mineral deposition. In the digestive tract, the main structural changes were late post-ecdysial loss of midgut cells and digestive gland B-cells (probably by extrusion) when restarting the feeding cycle. Pre-ecdysial increase and post-ecdysial decrease in storage lipids are also obvious. We present a quick moult-staging method to sort a great number of G. pulex for physiological or toxicological assays investigating how animals at specific periods of their moult cycle respond to both natural and anthropogenic environmental changes. [less ▲]

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See detailBioaccumulation of polybrominated diphenyl ethers (PBDEs) in Gammarus pulex: Relative importance of different exposure routes and multipathway modeling
Lebrun, Jérémie; Leroy, Delphine; Giusti, Arnaud ULg et al

in Aquatic Toxicology (2014), 154

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the ... [more ▼]

Characterizing the exposure routes of an organism and its ability to regulate accumulated contaminants is a crucial step toward developing a biomonitor. To date, very little data are available on the bioaccumulation kinetics of PBDEs in freshwater biota. This study aims at investigating the potential use of a litter-degrader widely distributed in European freshwaters, Gammarus pulex, as an indicator of exposure to PBDEs. In aquatic microcosms, gammarids were exposed to a mixture of brominated congeners (BDE-28, 47, 66, 85, 99, 100, 153, 154 and 183) to assess their ability to bioconcentrate PBDEs. Results show that all tested congeners are highly internalized by G. pulex and uptake rates of PBDEs are closely related to their partition coefficients (Kow). The determination of the elimination rate of BDE-47, the congener most readily accumulated by gammarids, indicated that metabolism and excretion of this congener are low in G. pulex, which argues in favor of its use as a quantitative biomonitor. Finally, bioaccumulation experiments were performed using contaminated leaves to determine the relative importance of dietary uptake in the contamination of gammarids. Even though water is the preeminent exposure route, a significant uptake of BDE-47 through food was observed (27%). We propose a biodynamic model that takes into account both exposure routes to describe BDE-47 bioaccumulation. This study supports the use of this ubiquitous amphipod as an early warning monitor of the bioavailable contamination of freshwaters by PBDEs. [less ▲]

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See detailEffects of two PBDE congeners on the moulting enzymes of the freshwater amphipod Gammarus pulex.
Gismondi, Eric ULg; Thomé, Jean-Pierre ULg

Poster (2014, May)

Polybrominated diphenyl ethers (PBDEs) constitute a class of chemical compounds included to the composition of usual products such as plastics, textiles or electrical equipment, due to their flame ... [more ▼]

Polybrominated diphenyl ethers (PBDEs) constitute a class of chemical compounds included to the composition of usual products such as plastics, textiles or electrical equipment, due to their flame retardants properties. Since 2004, PBDEs were banned in Europe and listed as Priority Substances within the European Union Water Frame Work Directive. Unfortunately, the release of PBDEs always occurs in ecosystems due to their presence in products currently in use and new products manufactured using recycled PBDE-containing material. However, only few studies have investigated their impacts on freshwater invertebrates. This work aimed to study the effects of BDE-47 and BDE-99 congeners on the chitobiase and chitinolytic enzymes activities of the freshwater amphipod Gammarus pulex, according to gender, PBDE concentration and time of exposure. In addition, the bioaccumulation of BDE-47 and BDE-99 were measured. The results revealed that there was a dose-response relationship for the PBDE accumulation in G. pulex, whatever the gender and the PBDE congeners. Female G. pulex bioaccumulated more PBDE than males, and especially BDE-99 which was more accumulated than BDE-47. Moreover, PBDE exposures for 96hrs have caused the inhibition of chitobiase and chitinolytic enzymes activities. This study not only indicate the importance of taking into account various confounding factors (gender, congeners, concentration) to understand the PBDE effects, but underline also disruptions of enzymes activities involved in the molting process. These disturbances suggest effects on the gammarid development and reproduction, and consequently on the gammarid population. [less ▲]

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See detailExpression of biotransformation and oxidative stress genes in the giant freshwater prawn Macrobrachium rosenbergii exposed to chlordecone
Gaume, B; Dodet, N; Thomé, Jean-Pierre ULg et al

in Environmental Science and Pollution Research (2014), 22(11), 7991-8002

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See detailEfficient in vitro adipocyte model of long-term lipolysis: A tool to study the behavior of lipophilic compounds
Louis, C; Van Den Daelen; Tinant, G et al

in In Vitro Cellular and Developmental Biology - Animal (2014), 50(6), 507-518

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See detailEffect of a mediterranean diet during pregnancy on fetal growth and preterm delivery: Results from a French caribbean mother-child cohort study (TIMOUN)
Saunders, L; Guldner, L; Costet, N et al

in Paediatric and Perinatal Epidemiology (2014), 28(3), 235-244

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See detailHypertensive disorders of pregnancy and gestational diabetes mellitus among French Caribbean women chronically exposed to chlordecone
Saunders, L; Kadhel, P; Costet, N et al

in Environment International (2014), 68

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See detailChlordecone exposure, length of gestation, and risk of preterm birth
Kadhel, P; Monfort, C; Costet, N et al

in American Journal of Epidemiology (2014), 179(5), 536-544

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See detailRespond to "interpreting exposure biomarkers in pregnancy"
Kadhel, P; Monfort, C; Costet, N et al

in American Journal of Epidemiology (2014), 179(5), 548-549

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See detailEffects of age, adipose percent, and reproduction on PCB concentrations and profiles in an extreme fasting north pacific marine mammal
Peterson, S. H.; Hassrick, J. L.; Lafontaine, Anne ULg et al

in PLoS ONE (2014), 9(4), 96191

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See detailLocalization and in situ absolute quantification of chlordecone in the mouse liver by MALDI imaging
Lagarrigue, M; Lavigne, R; Tabet, E et al

in Analytical Chemistry (2014), 86(12), 5775-5783

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See detailPCB-153 shows different dynamics of mobilisation from differentiated rat adipocytes during lipolysis in comparison with PCB-28 and PCB-118
Louis, Caroline; Tinant, G; Mignolet, E et al

in PLoS ONE (2014), 9(9), 106495

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See detailEffects of two PBDE congeners on the moulting enzymes of the freshwater amphipod Gammarus pulex
Gismondi, Eric ULg; Thomé, Jean-Pierre ULg

in Environmental Pollution (2014), 191

Polybrominated diphenyl ethers (PBDEs) are abundant in aquatic environment. However, only few studies have investigated their impacts on freshwater invertebrates. This work aimed to study the effects of ... [more ▼]

Polybrominated diphenyl ethers (PBDEs) are abundant in aquatic environment. However, only few studies have investigated their impacts on freshwater invertebrates. This work aimed to study the effects of BDE-47 and BDE-99 congeners on the chitobiase and chitinolytic enzymes activities of the freshwater amphipod Gammarus pulex, according to gender, PBDE concentration and time of exposure. In addition, the bioaccumulation of BDE-47 and BDE-99 were measured. Results revealed that females have bioaccumulated more PBDE than males, and BDE-99 was more accumulated than BDE-47. PBDE exposures for 96hrs have caused chitobiase and chitinolytic enzymes inhibition. This study not only indicate the importance of taking into account various confounding factors (gender, congeners, concentration) to understand PBDE effects, but underline also disruptions of molting enzymes activities. These disturbances suggest effects on the gammarid development and reproduction, and consequently effects on the gammarid population, and on a larger scale, a dysfunction of the ecosystem. [less ▲]

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See detailProteomic Analysis of the Reproductive Organs of the Hermaphroditic Gastropod Lymnea stagnalis Exposed to Different Endocrine Disrupting Chemicals
Giusti, Arnaud ULg; Leprince, Pierre ULg; Mazzucchelli, Gabriel ULg et al

in PLoS ONE (2013), 8(11), 81086

Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these ... [more ▼]

Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD). In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 μg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin) could constitute relevant evidence of interaction of EDCs with reproductive pathways that are under the control of the endocrine system of L. stagnalis. [less ▲]

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