Overexpression of copper zinc superoxide dismutase impairs human trophoblast cell fusion and differentiation.: SOD-1 and Human Trophoblast Differentiation

The syncytiotrophoblast is the major component of the human placenta, involved in feto-maternal exchanges and secretion of pregnancy-specific hormones. Multinucleated syncytiotrophoblast arises from fusion of mononuclear cytotrophoblast cells. In trisomy 21-affected placentas, we recently have shown that there is a defect in syncytiotrophoblast formation and a decrease in the production of pregnancy-specific hormones. Due to the role of oxygen free radicals in trophoblast cell differentiation, we investigated the role of the key antioxidant enzyme, copper/zinc superoxide dismutase, encoded by chromosome 21 in in vitro trophoblast differentiation. We first observed that overexpression of superoxide dismutase in normal cytotrophoblasts impaired syncytiotrophoblast formation. This was associated with a significant decrease in mRNA transcript levels and secretion of hCG and other hormonal markers of syncytiotrophoblast. We confirmed abnormal cell fusion by overexpression of green fluorescence protein-tagged superoxide dismutase in cytotrophoblasts. In addition, a significant decrease in syncytin transcript levels was observed in superoxide dismutase-transfected cells. We then examined superoxide dismutase expression and activity in isolated trophoblast cells from trisomy 21-affected placentas. Superoxide dismutase mRNA expression (P < 0.05), protein levels (P < 0.01), and activity (P < 0.05) were significantly higher in trophoblast cells isolated from trisomy 21-affected placentas than in those from normal placentas. These results suggest that superoxide dismutase overexpression may directly impair trophoblast cell differentiation and fusion, and superoxide dismutase overexpression in Down's syndrome may be responsible at least in part for the failure of syncytiotrophoblast formation observed in trisomy 21-affected placentas

STIMULATION OVARIENNE CHEZ DES FEMMES INFERTILES N'AYANT QU'UNE SEULE TROMPE SAINE

PARIS-BIUM (751062103) / SudocCentre Technique Livre Ens. Sup. (774682301) / SudocSudocFranceF

Comment aider les couples à mieux concevoir ?

PARIS7-Xavier Bichat (751182101) / SudocSudocFranceF

Performance measurement of professors at two European universities : A study at the IECS Ecole de Management de Strasbourg in France and the Europa-

Background: In a context of belt-tightening policy and of increasing competition between universities in France and in Germany, universities and therefore professors are required to increase their efficiency and to provide evidence of it. Performance measurement systems are assumed to increase transparency and incentives within the university sector. Purpose: The purpose of this thesis is to analyze to which extent performance measurement of professors at one French and one German university is relevant and how this performance can be measured. The study is conducted at the business school l’IECS Ecole de Management de Strasbourg (France) and within the Faculty of Business &amp; Economics at the Europa-Universität Viadrina in Frankfurt an der Oder (Germany). Method: Performance measurement is considered through the study and the comparison of two universities. Based on a theoretical framework including theories from the private sector, the public sector and the university sector, several in-depth interviews are conducted to collect facts and opinions from both professors and administrators and from both the IECS and the Viadrina. Conclusion: This study assesses the relevance of the measurement performance of professors at the IECS and the Viadrina. It provides also the main areas where professors’ performance should be measured and the main methods to measure this performance. Lastly the thesis raises several issues linked to performance measurement such as the organizational culture of universities, the utilisation of performance measurement system information and the impacts of performance measurement

Impact des programmes de physique au lycée sur la première année d’enseignement supérieur

Suite au changement des programmes de physique au lycée, la commission enseignement de la Société Française de Physique (SFP) a mené en 2014 une enquête auprès des enseignants du supérieur. Malgré un comportement plus actif des étudiants, les collègues ont constaté des difficultés à résoudre des problèmes de physique. Ceci est dû à un manque de rigueur dans le raisonnement et au fait que nombre de concepts ne sont pas maîtrisés. L’absence de liens entre physique et mathématiques dans les programmes ne fait que renforcer ces tendances. Malgré un élargissement de leur culture scientifique, les connaissances des étudiants sont très cloisonnées et non consolidées

Sampling retail pistachios for aflatoxin B1: Effect of sample size and number of samples taken for evaluating the contamination level.

International audienc

Sampling retail pistachios for aflatoxin B1: Effect of sample size and number of samples taken for evaluating the contamination level.

International audienc

Sperm parameters and male fertility after bariatric surgery: three case series

International audienceRecent studies have underlined the impact of obesity on sperm parameters, but very few data are available on the effect of weight loss on male fertility. This article reports the case series of three male patients who underwent rapid and major weight loss following bariatric surgery and the consequences of this surgery on semen parameters and fertility. A severe worsening of semen parameters was observed during the months after bariatric surgery, including extreme oligoasthenoteratozoospermia, but azoospermia was not observed. This effect may hypothetically be the result of two opposite mechanisms: (i) the suppression of the deleterious effects of obesity; and (ii) the negative impact of both nutritional deficiencies and the release of toxic substances. Information about potential reproductive consequences of bariatric surgery should be given to patients and sperm cryopreservation before surgery proposed. However, for one case, the alterations of spermatogenesis were reversible 2 years after the surgical procedure. Finally, intracytoplasmic sperm injection with fresh spermatozoa after male bariatric surgery can be successful, as demonstrated here, where clinical pregnancies were obtained for two out of the three couples. (C) 2011, Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved