Publications by authors named "Defossez A"

Mediterranean forests represent critical areas that are increasingly affected by the frequency of droughts and fires, anthropic activities and land use changes. Optical remote sensing data give access to several essential biodiversity variables, such as species traits (related to vegetation biophysical and biochemical composition), which can help to better understand the structure and functioning of these forests. However, their reliability highly depends on the scale of observation and the spectral configuration of the sensor.

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Objective: The objective was to develop an animal model using bacterial inoculation to evaluate tissue integration and tolerance to meshes used in genital prolapse surgery.

Study Design: We placed three different meshes under the abdominal skin of 120 Wistar rats: a polypropylene monofilament non-coated mesh (Parietene), a polypropylene monofilament collagen-coated mesh (Ugytex) and a polyethylene terephthalate mesh (Mersuture). We performed bacterial inoculation just after implantation with 1 ml of 10(7) colonies forming unit (CFU) of Staphylococcus epidermidis or Escherichia coli.

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Background: Severe oligozoospermia is characterized by sperm count fluctuations that may result in insufficient quantities of motile sperm for ICSI on the day of oocyte retrieval, thus necessitating testicular biopsy. To avoid this, we proposed that patients, with transient azoospermia or repeatedly low sperm counts, make a safety pool of frozen spermatozoa before ICSI attempts.

Methods: Seventy cryptozoospermic (<10(3) spermatozoa/ml) and 46 oligozoospermic patients (10(3)-10(5)/ml) were included.

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Introduction: The molecular mechanism of human embryo implantation is poorly understood. The role of MUC4 mucin, present in endometrial epithelium, has never been explored, and results obtained in animal studies strongly suggest a role in implantation. We investigated the role of MUC4 in human embryo implantation.

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Objective: To evaluate the tissue integration of and tolerance to five different mesh types used in genital prolapse surgery to provide mechanical support.

Study Design: We placed five different meshes (Vicryl, Vypro, Prolene, Prolene soft, and Mersuture) on the peritoneums of 12 pigs. After 10 weeks, we used light microscopy to analyze the tissue integration of and tolerance to these meshes.

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Background: Testicular sperm extraction (TESE) associated with ICSI gives patients suffering from non-obstructive azoospermia (NOA) the possibility of becoming a father. The success rate of TESE based on sperm recovery is approximately 50%, and the commonly used non-invasive parameters are not predictive enough. Only the invasive testis biopsy has a good prognostic value.

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Background: Sperm motility evaluation is associated with fertility in IVF programmes. The visual estimation of sperm motility is extremely subjective. Hence, alternative methods are required.

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Background: Detection of apoptosis in sperm samples may help evaluate sperm quality. Recently, it has been suggested that in some ejaculated sperm populations, apoptosis is caspase dependent. The aim of this study was to investigate the presence of activated caspases and examine possible correlations with apoptosis and sperm parameters in semen samples prepared for IVF.

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Inhibin B is a testicular peptide hormone that regulates FSH secretion in a negative feedback loop. Inhibin B is a dimer of an alpha and a beta(B) subunit. In adult testes, the cellular site of production is still controversial, and it was hypothesized that germ cells contribute to inhibin B production.

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A two-channel scenario for the conductivity of underdoped YBa 2Cu 3O (7-delta) is proposed. One is the single-particle excitations channel, which dominates in the optimally doped material, whose resistivity is linear as a function of temperature. The other one gives a contribution which merges the 3D Aslamazov-Larkin fluctuation conductivity at low temperature and obeys a power law at high temperature, depending on two superconductive parameters (T(c) and the zero temperature coherence length xi(c0)) and an energy scale Delta(*).

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Treatment of diabetes mellitus by transplantation of isolated pancreatic islets could constitute an alternative to human pancreas allograft. Before transplantation, porcine islets are submitted to a procedure of isolation and purification. The quality of islets through these different steps may be assessed by morphological and functional studies.

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Senile plaque and paired helical filament (PHF) formation are characteristic of Alzheimer's disease, but the mechanisms leading to these lesions still remain unclear. To understand them better, we have performed different immunolabellings of amyloid protein and PHF. We describe a very specific immunodetection of PHF with AD2, a monoclonal antibody directed against a hyperphosphorylated epitope of PHF-tau, and use double immunolabelling to show that PHF and plaque amyloid are discretely labelled by different antibodies.

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Amyloid angiopathy is a common pathological finding in Alzheimer's disease. It usually involves leptomeningeal and cortical vessels but spares the white matter. It may cause lobar cerebral hemorrhages at a late stage of the disease.

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We performed an immunocytochemical study of cerebral cortex from cases of Alzheimer's disease and from aged nondemented controls, using periodic acid pretreatment and polyclonal beta-protein antibodies. In addition to senile plaques (SP) and amyloid angiopathy (AA), the beta-protein antibodies detected band-like deposits present throughout the cortical layers. Moreover, large plaque-like infiltrations with diffuse and amorphous characteristics were observed in the cortical gray and white matter, and these deposits were often associated with capillaries.

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It has been suggested that copper-zinc superoxide dismutase (CuZn SOD) increment, by accelerating hydrogen peroxide formation, might promote oxidative damage within trisomy 21 cells and might be involved in the various neurobiological abnormalities found in Down's syndrome such as premature aging and Alzheimer-type neurological lesions. In order to test this hypothesis, we have developed strains of transgenic mice carrying the human CuZn SOD gene. The human transgene expression resulted in increased CuZn SOD activity predominantly in the brain (1.

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The distribution of cells containing copper-zinc superoxide dismutase (CuZn SOD) protein and mRNA was studied in hippocampi from normal humans and patients with Alzheimer's disease (AD) by using immunohistochemistry and in situ hybridization. Using antisera against native and denatured CuZn SOD protein, we have determined that immunostaining was intense in pyramidal neurons of the cornu ammonis, in granule cells of the dentate gyrus and very weak in other cells. In the hippocampus of an Alzheimer's patient, successive immunostaining of the same tissue section by antiCuZn SOD and antipaired helical filaments antisera show that both normal and degenerating cells were labeled by the antiCuZn SOD antiserum.

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To determine the possible role of Wallerian degeneration secondary to the grey matter neuronal loss in the pathogenesis of "leuko-araiosis", computerised tomography (CT) of the brain was studied in 98 normotensive and non diabetic subjects free of cardiac diseases: 32 with Alzheimer's disease, 36 with Parkinson's disease, eight with progressive supranuclear palsy, and 22 controls. In Alzheimer's disease, leuko-araiosis scores were greater than in control subjects. Leuko-araiosis was more prominent in anterior periventricular areas in Parkinson's disease and progressive supranuclear palsy, and in posterior periventricular areas in Alzheimer's disease.

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Progress in the search for the cause of Alzheimer's disease is considerably hampered by the lack of animal or in vitro model. We have shown that in Alzheimer's disease two pathological variants of Tau proteins, called Tau 64 and Tau 69, are regularly present in neural tissue undergoing neurofibrillary degeneration. Beside their diagnostic value, Tau 64 and Tau 69 might enable such a model to be devised at long last.

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