References of "Thomé, Jean-Pierre"
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See detailDietary early-life exposure to contaminated eels does not impair spatial cognitive performances in adult offspring mice as assessed in the Y-maze and the Morris water maze
Dridi, ImenI; Leroy, Delphine; Guignard, Cedric et al

in Nutrition Research (in press)

Many environmental contaminants are introduced via the diet and may act as neurotoxins and endocrine disrupters, especially influencing growing organisms in early life. The purpose of this study was to ... [more ▼]

Many environmental contaminants are introduced via the diet and may act as neurotoxins and endocrine disrupters, especially influencing growing organisms in early life. The purpose of this study was to examine whether dietary exposure of dams to fish naturally contaminated with xenobiotics, especially with polychlorinated biphenyls (PCBs) and heavy metals (e.g. mercury and lead), resulted in cognitive function deficits in adult offspring mice. Daily, four groups of dams (n = 10/group) ingested standard diet plus paste with/without eels, during gestation and lactation, from gestational day (GD) six until post natal day (PND) 21 (weaning). Dams orally ingested a standardized amount of eel (0.8 mgkg-1 d-1) containing the six non-dioxin-like (NDL) PCBs (σ6 NDL-PCBs: 28, 52, 101, 138, 153, and 180) at 0, 85, 216, and 400 ngkg-1 d-1. Results showed that early-life exposure to contaminated eels did not (compared to non-exposed controls) impair immediate working memory in the Y-maze in the offspring assessed at PND 38. Furthermore, it did not significantly impact spatial learning and retention memory as measured in the Morris water maze in adult offspring mice (PND 120-123). Our results suggest that perinatal exposure to contaminated eels does not affect spatial cognitive performances, as assessed by the Y-maze and Morris water maze at adult age. Adverse effects of xenobiotics reported earlier might be camouflaged by beneficial eel constituents, such as n-3 fatty acids. However, additional studies are needed to differentiate between potential positive and negative effects following consumption of food items both rich in nutrients and contaminants. © 2014 Elsevier Inc. [less ▲]

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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 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 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 detailFlore et faune de l'estran. Régions de Wimereux (Pas-de-Calais) et de Roscoff (Finistère)
Bussers, Jean-Claude ULg; Jeuniaux, Charles; Thomé, Jean-Pierre ULg et al

Learning material (2014)

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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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See detailImpact of anti-androgenic substances on gametogenesis of the rotifer Brachionus calyciflorus
Cruciani, Valentina ULg; Thomé, Jean-Pierre ULg; Joaquim-Justo, Célia ULg

Poster (2013, October 01)

Several studies have shown that pollutants with anti-androgenic activity have an impact on the sexual reproduction of the rotifer Brachionus calyciflorus (Joaquim-Justo et al., submit; Preston et al ... [more ▼]

Several studies have shown that pollutants with anti-androgenic activity have an impact on the sexual reproduction of the rotifer Brachionus calyciflorus (Joaquim-Justo et al., submit; Preston et al., 2001). The effects observed are compatible with the phenomenon of endocrine disruption. Fenitrothion, a non-steroidal anti-androgen induces a decrease in fertilization rate following exposure below or equal to 0,5 mg L-1.. The steroidal anti-androgen, cyproterone acetate increases number of cysts in population exposed to concentrations below or equal to 0,5 mg L-1. Cross mating experiments showed that effects of fenitrothion are due to an impact on males exclusively, while effects of cyproterone acetate exposition are due to an impact on females exclusively. In this study, we investigated the impact of fenitrothion on spermatogenesis and observed a decrease in the spermatozoa production and mobility with concentrations down to 0,5 mg L-1. We report a detailed description of the morphology of the male reproductive apparatus in B. calyciflorus based on optic, transmission electron and scanning electron microscopy in controls and exposed individuals. [less ▲]

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See detailReproductive impacts of tributyltin (TBT) and triphenyltin (TPT) in the hermaphroditic freshwater gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Barsi, Alpar; Dugué, Maël et al

in Environmental Toxicology & Chemistry (2013), 32(7), 1552-1560

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 ... [more ▼]

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 at comparing the relative toxicity of TBT and TPT under similar laboratory conditions in the 0–600 ng Sn/L range. 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 21d semi-static test. Frequency of abnormal eggs was assessed as an additional endpoint. TPT 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, since snail responses to TBT could be detected at concentrations as low as 19 ng Sn/L. However, the putative mode of action of the two 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 to the sensitivity of prosobranch molluscs with different habitats and different reproductive strategies. [less ▲]

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See detailPersistent Organochlorine Pollutants with Endocrine Activity and Blood Steroid Hormone Levels in Middle- Aged Men
Emeville, Elise; Giton, Frank; Giusti, Arnaud ULg et al

in PLoS ONE (2013), 8(6), 66460

Abstract Background: Studies relating long-term exposure to persistent organochlorine pollutants (POPs) with endocrine activities (endocrine disrupting chemicals) on circulating levels of steroid hormones ... [more ▼]

Abstract Background: Studies relating long-term exposure to persistent organochlorine pollutants (POPs) with endocrine activities (endocrine disrupting chemicals) on circulating levels of steroid hormones have been limited to a small number of hormones and reported conflicting results. Objective: We examined the relationship between serum concentrations of dehydroepiandrosterone, dehydroepiandrosterone sulphate, androstenedione, androstenediol, testosterone, free and bioavailable testosterone, dihydrotestosterone, estrone, estrone sulphate, estradiol, sex-hormone binding globulin, follicle-stimulating hormone, and luteinizing hormone as a function of level of exposure to three POPs known to interfere with hormone-regulated processes in different way: dichlorodiphenyl dichloroethene (DDE), polychlorinated biphenyl (PCB) congener 153, and chlordecone. Methods: We collected fasting, morning serum samples from 277 healthy, non obese, middle-aged men from the French West Indies. Steroid hormones were determined by gas chromatography-mass spectrometry, except for dehydroepiandrosterone sulphate, which was determined by immunological assay, as were the concentrations of sex-hormone binding globulin, follicle-stimulating hormone and luteinizing hormone. Associations were assessed by multiple linear regression analysis, controlling for confounding factors, in a backward elimination procedure, in multiple bootstrap samples. Results: DDE exposure was negatively associated to dihydrotestosterone level and positively associated to luteinizing hormone level. PCB 153 was positively associated to androstenedione and estrone levels. No association was found for chlordecone. Conclusions: These results suggested that the endocrine response pattern, estimated by determining blood levels of steroid hormones, varies depending on the POPs studied, possibly reflecting differences in the modes of action generally attributed to these compounds. It remains to be investigated whether this response pattern is predictive of the subsequent occurrence of disease. [less ▲]

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See detailEffects of tributyltin (TBT) and triphenyltin (TPT) on the reproduction of the freshwater snail Lymnaea stagnalis
Lagadic, Laurent; Giusti, Arnaud ULg; Barsi, Alpar et al

Conference (2012, December 10)

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See detailStare-Capmed : Présentation générale du projet et exemple d'une action : "Impact de l'ancrage sur la dynamique des herbiers de posidonies".
Michel, Loïc ULg; Champenois, Willy ULg; Borges, Alberto ULg et al

Conference (2012, May 16)

STARE-CAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) est un projet de recherche mis en place par Stareso S.A.S. depuis ... [more ▼]

STARE-CAPMED (STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystems Drifts) est un projet de recherche mis en place par Stareso S.A.S. depuis janvier 2012. Il a pour objectif d’établir un site de référence à long terme pour la compréhension, par la recherche fondamentale, des processus de l’évolution des écosystèmes méditerranéens côtiers et océaniques en réponse aux changements actuels globaux et locaux des pressions anthropiques. Centré sur la Baie de Calvi et le proche large, il vise à fournir un référentiel basé sur des mesures à haute fréquence qui doivent pouvoir complémenter les réseaux de surveillance basse fréquence et de recherches existants et ainsi faire progresser la compréhension des processus. En outre, le projet doit fournir aux utilisateurs finaux (collectivités locales et régionales, administrations nationales, ...) des orientations de gestion basées sur l’analyse étayée des processus en jeux. Financé par l’Agence de l’eau RMC et la Collectivité Territoriale de Corse, le projet, multidisciplinaire, se décline actuellement selon 10 axes de travail : • Suivi du cadre hydrographique et physico-chimique • Suivi et quantification des pressions anthropiques • Ecosystème planctonique • Benthos de substrat meuble • Benthos de substrat dur et faune vagile • Phanérogames marines et écosystèmes associés • Mouillages et processus d’altération des herbiers de posidonies • Ecotoxicologie et polluants émergents • Bilan CO2 et métabolisme des écosystèmes • Zones protégées, espèces nouvelles, recrutement Pour chacun de ces axes, la stratégie d’échantillonnage est basée sur la comparaison de données obtenues durant des périodes où l’impact anthropique est faible (octobre-avril) avec celles obtenues durant des périodes de pression intense (mai-septembre), et sur la comparaison de données issues de sites de référence peu impactés avec celles provenant de sites où l’impact anthropique est reconnu. A titre d’exemple, le but de l’action "Mouillages et processus d’altération des herbiers de posidonies" est de mettre en évidence les conséquences des altérations liées à l’arrachage de faisceaux de posidonies sur la vitalité de l’herbier. Des zones où la pression de mouillage est reconnue seront définies sur base des travaux de cartographie de l’herbier, également réalisés dans le cadre du projet STARE-CAPMED. Elles seront comparées avec des zones d’herbiers sains témoins par la caractérisation du sédiment (mesures de compacité in situ, mesures des concentrations en O2 et nutriments et du pH de l’eau interstitielle, granulométrie et teneur en matière organique du sédiment, proportions de rhizomes et morts) ainsi que par la définition de l’état physiologique des faisceaux de posidonies (mesures biométriques classiques, analyses des contenus élémentaires en carbone, azote et phosphore) et par l’application d’indices écologiques définis par la DCE (PREI, BIPO, …). Les résultats obtenus permettront d’avoir une vue d’ensemble des processus par lesquels l’impact physique des mouillages de bateaux de plaisance occasionne des dégâts aux herbiers de posidonies. Ils pourront ainsi fournir une base de connaissances solide aux gestionnaires soucieux de limiter cet impact. [less ▲]

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See detailFrom field to laboratory studies: case of selenium in Chelonians
Dyc, Christelle ULg; Thomé, Jean-Pierre ULg; Das, Krishna ULg

in Proceedings of the 32nd Annual Symposium on Sea Turtle Biology and Conservation (2012, March)

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See detailScaphandre La science rencontre l'art: L'art
Haubruge, Eric ULg; Bay, Daniel ULg; Semal, Jean et al

in Haubruge, Eric; Bay, Daniel; Semal, Jean (Eds.) Scaphandre La science rencontre l'art (2012)

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See detailFlux-based Risk Assessement of the impact of Contaminants on Water resources and ECOsystems
Jamin, Pierre ULg; Dujardin, Juliette; Crèvecoeur, Sophie et al

Report (2012)

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See detailFlux-based risk assessment of the impact of contamnants on water ressources and ecosystems - FRAC-WECO.
Jamin, Pierre ULg; Dujardin, J.; Crévecoeur, Sophie et al

Report (2012)

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See detailUsing sets of behavioral biomarkers to assess short-term effects of pesticide: a study case with endosulfan on frog tadpoles
Denoël, Mathieu ULg; D'hooghe, Bastien; Ficetola, G. Francesco et al

in Ecotoxicology (2012), 21(4), 1240-1250

Pesticides and other chemicals often have detrimental effects at environmental concentrations. Many amphibian species are particularly threatened because of their susceptibility but also because wetlands ... [more ▼]

Pesticides and other chemicals often have detrimental effects at environmental concentrations. Many amphibian species are particularly threatened because of their susceptibility but also because wetlands are often polluted. Behavioral assessments of toxicity have the advantage of showing sublethal effects but quantitative measures at varied scales of integrations are rarely considered together. In this study, we aimed at showing that these behavioral endpoints could be differently affected across time and concentrations, and be biomarkers of toxicity. To this end, we tested the effects of an organochlorine pesticide (endosulfan) on amphibians during a standard 96 h test. We evaluated possible lag effects in continuing the analyses after removal of the pesticide. The study was based on 240 tadpoles (4 pesticide treatments: 0.4, 3, 22, and 282 lg/l, 1 control and 1 solvent-control). Abnormal behaviors such as lying and swirling rapidly were exhibited only in the presence of the pesticide. Essential functions such as breathing and feeding were deeply affected by the pesticide: contaminated tadpoles breathed and fed less than control tadpoles. They also moved less and occupied a more central position in the aquariums in the presence of the pesticide. A higher mortality was only found at the highest concentration. These results suggest that endosulfan is toxic to amphibians at environmental concentrations. Behavioral markers showed potential as early warning systems. They should thus be used in complement to other markers to detect sublethal effects only a few days after application of the pesticide and at concentrations where mortality does not occur. [less ▲]

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See detailReproductive impact and proteomic analysis of androgenic and anti-androgenic disruptors on the hermaphroditic freshwater gastropod Lymnaea stagnalis
Giusti, Arnaud ULg; Ducrot, Virginie; Joaquim-Justo, Célia ULg et al

Poster (2011, November)

In this study, e ects of two androgens (tributyltin and testosterone), one antiandrogen (cyproterone acetate) and one estrogen (chlordecone) on growth and reproduction were investigated in the ... [more ▼]

In this study, e ects of two androgens (tributyltin and testosterone), one antiandrogen (cyproterone acetate) and one estrogen (chlordecone) on growth and reproduction were investigated in the hermaphrodite gastropod Lymnaea stagnalis. In this study, exposure to a range of concentrations (ng/l to μg/l) of each chemical was performed during 21 days. e number of clutches and the number of eggs per clutch were monitored. A decrease in clutches laid per snail was observed after exposure to tributyltin (540, 1180 and 2600 ng/l) and chlordecone (10, 22, 50 and 110 μg/l). A signi cant decrease in egg laid per snail was observed after exposure to tributyltin (540, 1180 and 2600 ng/l) and chlordecone (50 and 110 μg/l). An increase of egg abnormalities ratio in exposed snails (atrophied albumen, polyembryonicity,...) was observed in L. stagnalis following exposure to testosterone (2, 22, 50 and 110 ng/l), cyproterone acetate (4,5 and 50 μg/l), tributyltin (110 and 244 ng/l) and chlordecone (4,5 and 10 μg/l). Investigation of alteration in protein expression in exposed snails was performed using proteomic analysis such as 2D-DIGE. Mass spectrometry identi cation was performed on proteins with altered expression. We could establish correlation between reproductive endpoints and changes in proteins involved in egg formation and in egg laying were underlined. Egg yolk ferritin, the main protein of egg yolk, was shown to be reduced signi cantly in relationship with a decrease of egg yolk quality after exposure to tributyltin 540 ng/l and cyproterone acetate 4,5 μg/l. Ovipostatin, a protein proved to reduce egg masses, was signi cantly over expressed in snails exposed to 50 μg/l of chlordecone and were in relationship with a reduction of clutches laid by individuals. Further western blot analysis on those proteins involved in the reproduction are underway. ese analysis will enable us to con rm and re ne with more speci city the 2D-DIGE results for the selected proteins. e results of this study can help to establish new biomarkers of exposure of endocrine disruptors in freshwater environment and can provide new insight on mode of action of endocrine disruptors in L. stagnalis. [less ▲]

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