Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
BACKGROUND: Human immunodeficiency virus (HIV)-infected patients have decreased immune response to vaccines. Few data are available about pandemic flu vaccination in this population. METHODS: We conducted a multicenter, patient-blinded, randomized trial in a cohort of HIV-infected adults. Patients received 2 injections 21 days apart of a AS03(A)-adjuvanted H1N1v vaccine containing 3.75 μg hemagglutinin (HA) or a nonadjuvanted H1N1v vaccine containing 15 μg HA to assess hemagglutination inhibition (HI) response and safety. RESULTS: A total of 309 patients were randomized, and 306 were vaccinated. After the first vaccine dose, HI titers ≥1:40 were observed in 93.4% of the patients in the adjuvanted group (A group) (n = 155) and in 75.5% in the nonadjuvanted group (B group) (n = 151) (P < .001); seroconversion rates were 88.8% and 71.2%, and factor increases in geometric mean titers (GMT) of 21.9 and 15.1, respectively. After 2 injections, 98.6% of patients of the A group and 92.1% of the B group demonstrated HI titers ≥1:40 (P = .018); seroconversion rates were 96.5% and 87.1%, respectively, and factor increases in GMT were 45.5 and 21.2, respectively. The majority of adverse events were mild to moderate in severity; no impact on CD4+ cell count or viral load has been detected. CONCLUSIONS: In HIV-1-infected adults, the AS03(A)-adjuvanted H1N1v vaccine yielded a higher immune response than did the nonadjuvanted one, with no impact on HIV infection.
ISSN: 0022-1899

hal-00875299
https://hal.archives-ouvertes.fr/hal-00875299
DOI : 10.1093/infdis/jir211
PUBMED : 21628666

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 National Institute of Environmental Health Sciences (NIEHS) National Institute of Environmental Health Sciences
Résumé : International audience
Long-term exposure to persistent pollutants with hormonal properties (endocrine-disrupting chemicals, EDCs) may contribute to the risk of prostate cancer (PCa). However, epidemiological evidence remains limited. We investigated the relationship between PCa and plasma concentrations of universally widespread pollutants, in particular p,p'-dichlorodiphenyl dichloroethene (DDE) and the non-dioxin like polychlorinated biphenyl congener 153 (PCB153). We evaluated before treatment 576 men with newly diagnosed PCa and 655 controls in Guadeloupe (French West Indies). Exposure was analyzed according to case-control status. Associations were assessed by unconditional logistic regression analysis, controlling for confounding factors. Missing data were handled by multiple imputation. We estimated a significant positive association between DDE and PCa (adjusted odds ratio [OR] 1.53; 95% CI 1.02, 2.30 for the highest versus lowest quintile of exposure; PTrend = 0.01). PCB153 was inversely associated with PCa (OR 0.30; 95% CI 0.19, 0.47 for the highest versus lowest quintile of exposure values; PTrend < 0.001). Also, PCB153 was more strongly associated to low-grade than high grade PCa. Associations of PCa with DDE and PCB153 were in opposite directions. This may reflect differences in the mechanisms of action of these EDCs, and although our findings need to be replicated in other populations, they are consistent with complex effects of EDCs on human health.
ISSN: 0091-6765

hal-01118553
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01118553
DOI : 10.1289/ehp.1408407
PUBMED : 25493337

Éditeur(s) : HAL CCSD American Society for Microbiology
Résumé : International audience
Molecular diagnosis of congenital toxoplasmosis or disseminated toxoplasmosis is based mainly on PCR. The repeated DNA element rep529 has become the main DNA target used in most PCR methods, whether laboratory developed or commercial. In this multicenter study, we evaluated the Toxoplasma ELITe MGB (Elitech) commercial kit by comparison with three reference quantitative PCR assays (RAs) used routinely in three proficient laboratories of the French National Reference Center for Toxoplasmosis network, using Toxoplasma calibrated suspensions diluted to obtain a range of concentrations from 0.1 to 10,000 parasites/ml. These suspensions were extracted with either the DNA extraction kit (EXTRAblood; Elitech) recommended by the manufacturer or the QIAamp DNA minikit (Qiagen). The Toxoplasma ELITe MGB assay was also evaluated on a panel of 128 clinical samples, including 56 amniotic fluid samples, 55 placenta samples, and various other samples, of which 95 originated from patients with proven toxoplasmosis. The ELITe MGB assay amplified low-concentration replicates (<10 parasites/ml) of calibrated suspensions less frequently than the RAs of 2/3 laboratories. Additionally, the combination of EXTRAblood and Toxoplasma ELITe MGB yielded poorer sensitivity than the combination of QIAamp DNA minikit and ELITe MGB for low parasite concentrations (P < 0.001 for 1 parasite/ml). On clinical samples, the sensitivity and the specificity of the commercial assay were 89% and 100%, respectively. The sensitivity ranged from 79% (placenta samples) to 100% (amniotic fluid samples). Overall, this study shows that the Toxoplasma ELITe MGB assay is suitable for the diagnosis of toxoplasmosis from non-cell-rich or non-hemoglobin-rich samples and that the EXTRAblood kit is not optimal.
ISSN: 0095-1137

hal-01526432
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526432
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526432/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526432/file/Evaluation%20of%20the%20Toxoplasma.pdf
DOI : 10.1128/JCM.02379-16

Éditeur(s) : HAL CCSD BioMed Central
Résumé : International audience
BACKGROUND: Environmental exposures, including dietary contaminants, may influence the developing immune system. This study assesses the association between maternal pre-parturition consumption of seafood and wheeze, eczema, and food allergy in preschool children. Fish and shellfish were studied separately as they differ according to their levels of omega-3 polyunsaturated fatty acids (which have anti-allergic properties) and their levels of contaminants. METHODS: The PELAGIE cohort included 3421 women recruited at the beginning of pregnancy. Maternal fish and shellfish intake was measured at inclusion by a food frequency questionnaire. Wheeze, eczema, and food allergy were evaluated by a questionnaire completed by the mother when the child was 2 years old (n = 1500). Examination of the associations between seafood intake and outcomes took major confounders into account. Complementary sensitivity analyses with multiple imputation enabled us to handle missing data, due mostly to attrition. RESULTS: Moderate maternal pre-parturition fish intake (1 to 4 times a month) was, at borderline significance, associated with a lower risk of wheeze (adjusted OR = 0.69 (0.45-1.05)) before age 2, compared with low intake (< once/month). This result was not, however, consistent: after multiple imputation, the adjusted OR was 0.86 (0.63-1.17). Shellfish intake at least once a month was associated with a higher risk of food allergy before age 2 (adjusted OR = 1.62 (1.11-2.37)) compared to low or no intake (< once/month). Multiple imputation confirmed this association (adjusted OR = 1.52 (1.05-2.21)). CONCLUSIONS: This study suggests that maternal pre-parturition shellfish consumption may increase the risk of food allergy. Further large-scale epidemiologic studies are needed to corroborate these results, identify the contaminants or components of shellfish responsible for the effects observed, determine the persistence of the associations seen at age 2, and investigate potential associations with health effects observable at later ages, such as allergic asthma.
ISSN: 1476-069X

Droits : info:eu-repo/semantics/OpenAccess
inserm-00926282
http://www.hal.inserm.fr/inserm-00926282
http://www.hal.inserm.fr/inserm-00926282/document
http://www.hal.inserm.fr/inserm-00926282/file/1476-069X-12-102.pdf
DOI : 10.1186/1476-069X-12-102

Éditeur(s) : HAL CCSD
Résumé : International audience
Objective To guide nosology and classification of patients with eosinophilic granulomatosis with polyangiitis (EGPA) based on phenotype and presence or absence of ANCA. Methods Organ manifestations and ANCA status were retrospectively analyzed based on the presence or not of predefined definite vasculitis features or surrogates of vasculitis in patients asthma, eosinophilia, and at least one systemic organ manifestation attributable to systemic disease. Results The study population included 157 patients (mean age 49.4 ± 14.1), with a follow-up of 7.4 ± 6.4 years. Patients with ANCA (31%) more frequently had weight loss, myalgias, arthralgias, biopsy-proven vasculitis, glomerulonephritis on biopsy, hematuria, leukocytoclastic capillaritis and/or eosinophilic infiltration of arterial wall on biopsy, and other renal disease. A total of 41% of patients had definite vasculitis manifestations (37%) or strong surrogates of vasculitis (4%), of whom only 53% had ANCA. Mononeuritis multiplex was associated with systemic vasculitis (p = 0.005) and with the presence of ANCA (p < 0.001). Overall, 59% of patients had polyangiitis as defined by definite vasculitis, strong surrogate of vasculitis, mononeuritis multiplex, and/or ANCA with at least one systemic manifestation other than ENT or respiratory. Patients with polyangiitis had more systemic manifestations including arthralgias (p = 0.02) and renal disease (p = 0.024), had higher peripheral eosinophilia (p = 0.027), and a trend towards less myocarditis (p = 0.057). Using predefined criteria of vasculitis and surrogates of vasculitis, ANCA alone were found to be insufficient to categorise patients with vasculitis features. Conclusion We suggest a revised nomenclature and definition for EGPA and a new proposed entity referred to as hypereosinophilic asthma with systemic (non vasculitic) manifestations. © 2016 Elsevier B.V.
Autoimmunity Reviews

hal-01467544
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01467544
DOI : 10.1016/j.autrev.2016.09.018
PUBMED : 27671089

Éditeur(s) : HAL CCSD American Society for Microbiology
Résumé : International audience
Toxoplasmosis is a life-threatening infection in immunocompromised patients (ICPs). The definite diagnosis relies on parasite DNA detection, but the incidence and burden of disease are ill-known in HIV-negative patients. A three-year retrospective study was conducted in 15 reference laboratories from the network of the French National Reference Center for Toxoplasmosis, to record the frequency of Toxoplasma DNA detection in ICPs, to review the molecular methods used for diagnosis and the prevention measures implemented in transplant patients. During the study period, out of 31,640 PCR performed in ICPs, 610 were positive (323 patients). Blood (n=337), cerebrospinal fluid (n=101) and aqueous humor (n=100) samples were more frequently positive. Chemoprophylaxis schemes in transplant patients differed between centers. PCR follow-up of allogeneic hematopoietic stem-cell transplant (allo-HSCT) patients was implemented in 8/15 centers. Data from 180 patients (13 centers) were further analyzed regarding clinical setting and outcome. Only 68/180 (38%) patients were HIV+; the remaining 62% consisted in 72 HSCT, 14 solid-organ transplants, and 26 miscellaneous immunodeficiencies. Cerebral toxoplasmosis and disseminated toxoplasmosis were most frequently observed in HIV and transplant patients, respectively. Of 72 allo-HSCT patients with a positive PCR, 23 were asymptomatic; all were diagnosed in centers performing systematic blood PCR follow-up, and received specific treatment. Overall survival of allo-HSCT patients at two months was better in centers with PCR follow-up than in other centers (p<0.01). This study provides updated data on the frequency of toxoplasmosis in HIV-negative ICPs and suggests that regular PCR follow-up of allo-HSCT patients could guide pre-emptive treatment and improve outcome.
ISSN: 0095-1137

hal-01134189
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01134189
DOI : 10.1128/JCM.03282-14
PUBMED : 25762774

Éditeur(s) : HAL CCSD National Institute of Environmental Health Sciences
Résumé : International audience
BACKGROUND: Women of reproductive age can be exposed to endocrine-disrupting chemicals (EDCs) at work, and exposure to EDCs in pregnancy may affect fetal growth. OBJECTIVES: We assessed whether maternal occupational exposure to EDCs during pregnancy as classified by application of a job exposure matrix was associated with birth weight, term low birth weight (LBW), length of gestation, and preterm delivery. METHODS: Using individual participant data from 133,957 mother-child pairs in 13 European cohorts spanning births from 1994 through 2011, we linked maternal job titles with exposure to 10 EDC groups as assessed through a job exposure matrix. For each group, we combined the two levels of exposure categories (possible and probable) and compared birth outcomes with the unexposed group (exposure unlikely). We performed meta-analyses of cohort-specific estimates. RESULTS: Eleven percent of pregnant women were classified as exposed to EDCs at work during pregnancy, based on job title. Classification of exposure to one or more EDC group was associated with an increased risk of term LBW [odds ratio (OR) = 1.25; 95% CI: 1.04, 1.49], as were most specific EDC groups; this association was consistent across cohorts. Further, the risk increased with increasing number of EDC groups (OR = 2.11; 95% CI: 1.10, 4.06 for exposure to four or more EDC groups). There were few associations (p < 0.05) with the other outcomes; women holding job titles classified as exposed to bisphenol A or brominated flame retardants were at higher risk for longer length of gestation. CONCLUSION: Results from our large population-based birth cohort design indicate that employment during pregnancy in occupations classified as possibly or probably exposed to EDCs was associated with an increased risk of term LBW.
ISSN: 0091-6765

hal-01405823
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01405823
DOI : 10.1289/EHP208
PUBMED : 27152464

Éditeur(s) : HAL CCSD National Institute of Environmental Health Sciences
Résumé : International audience
Background: Glycol ethers (GE) are widely used organic solvents. Despite the potential neurotoxicity of several families of organic solvents, little is known about the impact of GE on the neurodevelopment of infants and children. Objectives: We investigated the relation between urinary concentrations of GE metabolites in pregnant women and neurocognitive abilities in their 6-year-old children in the PELAGIE mother-child cohort. Methods: Five GE metabolites were measured in first morning void urine samples of 204 French pregnant women in early pregnancy (<19 weeks of gestation). Psychologists assessed the neurocognitive abilities of their 6-year-old children with the Wechsler Intelligence Scale for Children IV (WISC) and the Developmental Neuropsychological Assessment (NEPSY). We analyzed the results with linear (WISC) and Poisson regression models (NEPSY), adjusted for potential confounders, including child's stimulation at home. Results: GE metabolites were detected in 90-100% of maternal urine samples. The WISC Verbal Comprehension score was significantly lower for children with the highest tertile of urinary phenoxyacetic acid (PhAA) [beta (third vs. first tertile)=-6.53; 95% CI: -11.44, -1.62]. Similarly, the NEPSY Design Copying subtest score was lower in those with the highest tertile of urinary ethoxyacetic acid (EAA) [beta (third vs. first tertile)=-0.11; 95% CI: -0.21, 0.00]. The other GE metabolites we studied were not significantly associated with WISC or NEPSY scores. Conclusions: Prenatal urine concentrations of two GE metabolites were associated with lower WISC Verbal Comprehension Index scores and NEPSY Design Copying subscale scores, respectively, at age 6 years. PhAA is the primary metabolite of 2-phenoxyethanol (EGPhE), which is commonly found in cosmetics, and precursors of EAA are frequently used in cleaning agents. Additional research is needed to confirm our findings and further explore potential effects of prenatal GE exposures on neurocognitive performance in children.
ISSN: 0091-6765

hal-01519256
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01519256
DOI : 10.1289/EHP39
PUBMED : 27740510

Éditeur(s) : HAL CCSD National Institute of Environmental Health Sciences
Résumé : International audience
BACKGROUND: Glycol ethers are present in a wide range of occupational and domestic products. Animal studies have suggested that some of them may affect ovarian function. OBJECTIVE: To study the relation between women's exposure to glycol ethers and time to pregnancy. METHODS: Urine from randomly selected women in the PELAGIE mother-child cohort who had samples collected before 19 weeks of gestation was tested to measure eight glycol ether metabolites by chromatography coupled to mass spectrometry. Time to pregnancy was collected at the beginning of the pregnancy by asking women how many months they took to conceive. Associations between metabolite levels and time to pregnancy were estimated in 519 women with complete data using discrete-time Cox proportional hazards models to adjust for potential confounders. RESULTS: Glycol ether metabolites were detected in 6% (for ethoxyacetic acid) to 93% (for phenoxyacetic and butoxyacetic acids) of urine samples. Phenoxyacetic acid was the only metabolite with a statistically significant association with longer time to pregnancy (fecundability OR 0.82; 95% CI: 0.63, 1.06 for the second and third quartile combined; fecundability OR 0.70; 95% CI: 0.52, 0.95 for a fourth-quartile (≥1.38 mg/L) vs. first-quartile concentration (<0.14 mg/L)). This association remained stable after multiple sensitivity analyses. CONCLUSION: Phenoxyacetic acid, which was present in most of the urine samples tested in our study, was associated with increased time to pregnancy. This metabolite and its main parent compound, 2-phenoxyethanol, are plausible causes of decreased fecundability, but may also be surrogates for potential co-exposures frequently present in cosmetics.
ISSN: 0091-6765

hal-00866023
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00866023
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00866023/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-00866023/file/Urinary_Glycol_Ether-accepted.pdf
DOI : 10.1289/ehp.1206103

Éditeur(s) : HAL CCSD
Résumé : Anti-Müllerian hormone (AMH) is a member of the TGF-ß superfamily. AMH is well known for its role in Müllerian duct regression in male fetuses. Postnatally, AMH is secreted by granulosa cells (GCs) of small growing follicles (preantral and small antral). However, despite the increasing interest of ovarian AMH in clinics, little is known on its mechanism of action and its role in female reproductive tract. My PhD project focuses on the identification of AMH function in the female reproductive tract.AMH signals through a type II transmembrane serine/threonine kinase receptor (AMHR-II) which forms a complex with a type I serine/threonine kinase receptor (ActR-IA, BMPR-IA, BMPR-IB). The type II receptor phosphorylates serine and threonine residues of type I receptor. Once activated, the type I receptor phosphorylates the receptor-regulated Smads (R-Smad1/5/8) which interact with a common partner Smad4. The Smad complex accumulates into the nucleus and regulates target gene expression. This canonical signalling pathway is regulated at different levels, in particular by co-receptors which amplify or antagonize TGF-ß family members action. The type I receptors and R-Smads involved in AMH effects on post-natal GCs remain unknown. In addition, to date, no co-receptor has been found for AMH. To define the involvement of the different type I receptors, we used siRNA technology to inactivate Acvr1, Bmpr1a and Bmpr1b in GC. In parallele, we analysed GC extracted from conditional mutant mice for Acvr1 and Bmpr1a. We found that BMPR-IA is the most important type I receptor for AMH to transduce its signal in GC. A Smad-Gal4/UAS-luciferase reporter gene technology allowed us to show that Smad1 and 5 are involved in AMH signaling pathway. Recently, new BMPs coreceptors were found, RGMs for Repulsive Guidance Molecules. There are three RGMs : RGMa, b and c. Because AMH shares with BMPs its type I receptors and R-Smad proteins, we hypothesized that they also share the same co-receptors, the RGM. We showed that RGMb was the only one expressed in GC and after siRNA transfection we demonstrated that this coreceptor is not essential for AMH to transduce its signal.To date, only few AMH target genes have been identified. Aromatase (Cyp19a1) and LH receptor (Lhcgr) are down-regulated by AMH in rat and porcine GCs. We used micro-array technology (Affymetrix) by comparing Wt and knockout immature ovaries to find new AMH target genes. This experiment evidenced that Ovgp1 and Kcnj2 are two new potential AMH target genes in the ovary.The last part of my project was to define a potential role of AMH in murine uterus. Only one study showed that AMHR-II is expressed in the mouse myometrium. We showed that Amh gene is slightly expressed in uterus but the results are not confirmed at the protein level. Using PCR-array, we found a lot of differentially expressed genes between Wt and Amh KO uterus. Therefore, AMH could regulate uterine function through the modulation of different genes located in the myometrium.
L’hormone anti-Müllerienne (AMH) est un membre de la famille TGF-β impliquée dans la différenciation du tractus reproductif mâle. Elle est aussi exprimée par les cellules de la granulosa de l’ovaire adulte. Cependant, son rôle physiologique chez la femelle n’a pas encore été entièrement établi. Mon projet de thèse a pour objectif d’élucider le(s) rôle(s) de l’AMH dans le tractus reproductif femelle. L’AMH transduit ses effets par l’intermédiaire de deux récepteurs transmembranaires sérine/thréonine kinase : un récepteur de type II qui lui est spécifique (AMHR-II) et un récepteur de type I (ActR-IA, BMPR-IA, BMPR-IB) qu’elle partage avec les BMPs. Après fixation de l’hormone sur le récepteur de type II, celui-ci recrute et phosphoryle le récepteur de type I. Ce dernier phosphoryle à son tour les Smads spécifiques (Smad1, 5 et 8) qui s’associent à la Smad commune, Smad4. L’ensemble transloque dans le noyau et en association avec des facteurs de transcription régule les gènes cibles de l’hormone. L'utilisation de souris KO conditionnelles pour les récepteurs Acvr1 et Bmpr1a et d'une technique de siRNA dirigés contre chacun des trois récepteurs de type I a permis de mettre en évidence que le récepteur BMPR-IA est un acteur essentiel de la voie de signalisation de l'AMH dans les cellules de la granulosa. Pour déterminer la ou les Smad(s) impliquées, une technique de gènes rapporteurs, Smad-Gal4/UAS-luciférase, a été utilisée. Nous avons pu montrer que les Smad1 et 5 sont importantes pour la transduction du signal de l'AMH dans les cellules de la granulosa. Récemment des corécepteurs aux BMPs, les Repulsive Guidance Molecule (RGMs), ont été mis en évidence. L’AMH partageant sa voie de signalisation avec les BMPs, nous avons cherché à déterminer si ces corécepteurs pouvaient également intervenir dans la voie de signalisation de l’AMH. Il existe 3 types de RGMs: RGMa, RGMb et RGMc. Nous avons montré en q-PCR que seul RGMb est exprimé dans les cellules de la granulosa alors que les 3 RGMs sont exprimés dans l’ovaire. L'utilisation de siRNA dirigés contre RGMb a permis de montrer que ce récepteur n'est pas nécessaire à la transduction du signal de l'AMH. Actuellement, seuls deux gènes cibles de l’AMH sont connus dans les cellules de la granulosa : l’aromatase et le récepteur LH. Nous avons réalisé des analyses de puces à ADN (ou micro-array) pour décrire de nouveaux gènes cibles de l'AMH. L'analyse des puces a permis de décrire de nouveaux gènes régulés par cette hormone tels qu’Ovgp1 ou Kcnj2. La dernière partie de mon projet visait à déterminer un rôle potentiel de l'AMH dans l'utérus. En effet, le récepteur de cette hormone est exprimé dans le myomètre utérin de souris permettant de supposer qu’elle peut agir sur cet organe. Nous avons pu mettre en évidence une expression faible du gène de l’Amh dans l’utérus. En revanche, l’expression et la localisation de la protéine restent encore à définir. Une expérience de PCR-array a permis de montrer que de nombreux gènes sont différentiellement exprimés entre l’utérus Wt et l’utérus KO Amh. Ceci indique que l’AMH jouerait un rôle sur la régulation de la fonction utérine qu’elle soit exprimée ou non dans cet organe.
https://tel.archives-ouvertes.fr/tel-00989662

Droits : info:eu-repo/semantics/OpenAccess
NNT : 2014PA11T014
tel-00989662
https://tel.archives-ouvertes.fr/tel-00989662
https://tel.archives-ouvertes.fr/tel-00989662/document
https://tel.archives-ouvertes.fr/tel-00989662/file/VA_SEDES_LAURIANE_03042014.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
The purpose of this study is to identify links between the geothermal context and the conceptions in different initial teachers training, from the Caribbean and North America. The Caribbean Islands are located in a subduction zone, creating a great potential for geothermal energy. In Guadeloupe, this potential has been harnessed and a geothermal power plant produces about 5% of the local demand for electricity. It is called high temperature geothermy. In Quebec the bedrock mainly consists of ancient Precambrian rocks from the Canadian Shield, which does not allow for electricity production. The geothermal heat is used to regulate the temperature in buildings, to create spars, to grow crops and other purposes. It is called low temperature geothermy. This design-based research (Sandoval, W. et Al., 2004) takes part in the contextualization of sciences education research works (Blanchet, P. et Al., 2009, Anciaux, F. et Al., 2013) and in the continuation of the Gounouy project (Fecil, S. et Al., 2014). A project-based learning on geothermal energy has been set up with two groups of initial teachers training from the Université du Québec à Montréal (UQAM) and from the French West Indies University (UA). The purpose is to create collaborations between each group in order to enable them to encounter, recognize and formulate their conceptions. Further, they will collectively elaborate a more complex understanding of conceptions about geothermy. More specifically, the design used in this experiment aims to highlight context effects (Merlo-Leurette, S., Forissier, T., 2009). Context effects are pedagogical events occurring when there is a clash between the different conceptions of students, observed uring courses regarding different problematics related to geothermal energy. Communications via videoconferences were arranged so that the counterpart teams may discuss their investigative findings. Videos from the exchanges have been collected, as well as weekly summaries about student’s accomplishment, ideas, questions and feelings. Pre-test and post-test questionnaires on geothermal energy were submitted at the beginning and at the end of the project, to compare conceptions before and after the learning process. Collected data enables to bring out the student’s contextuality. Therefore, they highlight context effects, due to the differences between the geothermal contexts in Guadeloupe and in Montreal.This study is supported by the Geotref project.
CARIBBEAN ACADEMY OF SCIENCES 20 th GENERAL ASSEMBLY AND BIENNAL MEETING
Dehaies, Guadeloupe, France

hal-01534665
https://hal.univ-antilles.fr/hal-01534665