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Hôpital-Camfrout, France

Auger J.,Hopitaux Universitaires Paris Center
Proceedings. Biological sciences / The Royal Society | Year: 2013

Digit length ratios, especially the second-to-fourth digit ratio (2D : 4D), are associated with various pathological and behavioural conditions in many species including humans and are dependent upon prenatal androgen to oestrogen balance. It is unknown whether digit ratios are modified by environmental exposure to ubiquitous endocrine disruptors. We studied the effect on adult male Wistar rat digit ratios of a gestational exposure to the oestrogenic and antiandrogenic compounds bisphenol A (BPA), genistein and vinclozolin, in low doses, and in combination with investigating in parallel a possible sexual dimorphism of this trait. We also investigated the effects on the male progeny not exposed during gestation. X-rays were taken of the left and right forepaws, and 2D-5D proximal to distal phalanx distances were measured by a standardized procedure based on semi-automatic image analysis. We provide evidence that there is a sexual dimorphism of digit ratios in the Wistar rat, and we found that BPA alone or in combination with genistein and vinclozolin significantly feminized digit ratios in male rats. Intriguingly, significant feminization of digit ratios was also found in the unexposed male progeny of males that had been exposed to compound mixtures. In conclusion, prenatal environmental levels of endocrine-active substances permanently disrupt digit ratios. Digit ratio measurement in adults is thus a promising biomarker of prenatal exposure to low-dose endocrine disruptors in rodents, with potential implications for future studies in humans. Source

Pefura-Yone E.W.,University of Yaounde I | Fodjeu G.,District Hospital of Bouda | Kengne A.P.,University of Cape Town | Roche N.,Hopitaux Universitaires Paris Center | And 2 more authors.
Respiratory Medicine | Year: 2015

Background Little is known on the association between HIV infection and chronic obstructive pulmonary disease (COPD) in sub-Saharan Africa. We assessed the prevalence and investigated the determinants of COPD according to HIV status in a reference centre for HIV and tuberculosis (TB) management in Cameroon. Methods This case-control study involved 461 HIV-positive patients aged >18 years (cases) receiving care at the Yaounde Jamot Hospital (YJH) between November 2012 and February 2013, and in 461 age- and sex-matched HIV negative controls selected from the community through a multilevel stratified sampling. Logistic regression models were used to investigate the determinants of COPD. Results Each study group included 312 (67.7%) women. The mean age (standard deviation) was 42.6 (10.1) years in HIV positive group and 42.6 (10.2) years in HIV negative group. HIV infection was positively associated with COPD defined by the lower limit of normal FEV1/FVC ratio. In multivariable adjusted logistic regression, history of pulmonary TB, chronic respiratory symptoms and lower body mass index (BMI) were the main determinants of COPD in HIV infected patients (on antiretrovirals or not) regardless of the definition of COPD. Conclusions HIV infection is possibly a risk factor for COPD in this setting. The careful investigation of the determinants of COPD during routine diagnosis and care of people with HIV infection can aid the detection, further investigation, and improvement of the management of this group of patients. © 2014 Elsevier Ltd. All rights reserved. Source

Gaucher S.,University of Paris Descartes | Gaucher S.,Hopitaux Universitaires Paris Center | Jarraya M.,Hopitaux Universitaires Saint Louis Lariboisiere
Cell and Tissue Banking | Year: 2015

MTT assay is the gold standard for assessing skin sample viability but it is time-consuming. Here we compared the MTT test with two other assays for the assessment of skin viability. The MTT, PrestoBlue (colorimetric method) and LDH release assays were applied to fresh and cryopreserved skin. Skin viability was considered proportional to the optical density values of the relevant analytes. PrestoBlue did not reliably distinguish between fresh and cryopreserved skin. The LDH release assay did not allow us to establish a viability index. We recommend the MTT assay for assessing skin viability. © 2014, Springer Science+Business Media Dordrecht. Source

Auger J.,Hopitaux Universitaires Paris Center | Eustache F.,University of Paris Descartes | Rouiller-Fabre V.,French Institute of Health and Medical Research | Canivenc-Lavier M.C.,French National Institute for Agricultural Research | Livera G.,French Institute of Health and Medical Research
Asian Journal of Andrology | Year: 2014

In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance (EAS) exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action (MOA) of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool (together with the epidemiological approach) for understanding the reproductive effects and MOA of EASs, provided the pitfalls and limitations of the rodent models are known and considered. We also provide some evidence that classical rodent models may be refined for studying the multiple consequences of EAS exposure, not only on the reproductive axis but also on various hormonally regulated organs and tissues, among which several are implicated in the complex process of mammalian reproduction. Such models constitute an interesting way of approaching human exposure conditions. Finally, we show that organotypic culture models are powerful complementary tools, especially when focusing on the MOA. All these approaches have contributed in a combinatorial manner to a better understanding of the impact of EAS exposure on human reproduction. © 2014 AJA, SIMM & SJTU. All rights reserved. Source

Breuillard C.,University of Paris Descartes | Cynober L.,University of Paris Descartes | Cynober L.,Hopitaux Universitaires Paris Center | Moinard C.,University of Paris Descartes
Amino Acids | Year: 2015

Citrulline (Cit) is a non-essential amino acid whose metabolic properties were largely ignored until the last decade when it began to emerge as a highly promising nutrient with many regulatory properties, with a key role in nitrogen homeostasis. Because Cit is not taken up by the liver, its synthesis from arginine, glutamine, ornithine and proline in the intestine prevents the hepatic uptake of the two first amino acids which activate the urea cycle and so prevents amino acid catabolism. This sparing effect may have positive spin-off for muscle via increased protein synthesis, protein content and functionality. However, the mechanisms of action of Cit are not fully known, even if preliminary data suggest an implication of mTOR pathway. Further exploration is needed to gain a complete overview of the role of Cit in the control of nitrogen homeostasis. © 2015 Springer-Verlag Wien. Source

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