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Bielle F.,Pitie Salpetriere Hospital | Bielle F.,Paris-Sorbonne University | Bielle F.,French Institute of Health and Medical Research | Bielle F.,French National Center for Scientific Research | And 29 more authors.
American Journal of Surgical Pathology | Year: 2015

Chordoid glioma of the third ventricle (CG3V) is a rare tumor developing in a stereotyped localization. It has been related to the circumventricular organ of the lamina terminalis, in the anterior part of the third ventricle, but its oncogenesis is poorly understood. TTF-1 transcription factor is involved in the development and adult physiology of the ventral forebrain. We studied the histopathologic and immunohistochemical features of a multicentric series of 17 cases of CG3V. We described additional histologic patterns (solid, fibrosing, and fusiform) to the typical chordoid pattern. TTF-1 was constantly expressed in CG3V, as in developing and adult lamina terminalis. The anti-TTF-1 SPT24 clone was more sensitive than the 8G7G3/1 clone. No mutation of IDH1 R132, IDH2 R172, or BRAF V600 codons was found. We showed TTF-1 as a useful marker for the diagnosis of CG3V and the understanding of its oncogenesis. © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Duplomb L.,University of Burgundy | Duvet S.,Lille University of Science and Technology | Picot D.,University of Burgundy | Jego G.,University of Burgundy | And 21 more authors.
Human Molecular Genetics | Year: 2014

Cohen syndrome (CS) is a rare autosomal recessive disorder with multisytemic clinical features due to mutations in theVPS13Bgene, which has recently been describedencoding amandatorymembrane protein involved in Golgi integrity. As the Golgi complex is the place where glycosylation of newly synthesized proteins occurs, we hypothesized that VPS13B deficiency, responsible of Golgi apparatus disturbance, could lead to glycosylation defects and/or mysfunction of this organelle, and thus be a cause of the main clinical manifestations of CS. Theglycosylation status ofCSserumproteinsshowedaveryunusual pattern of glycosylation characterizedbya significant accumulationof agalactosylated fucosylated structures as well as asialylatedfucosylated structures demonstrating amajor defect of glycan maturation in CS. However, CS transferrin and a1-AT profiles, two liverderived proteins, were normal. We also showed that intercellular cell adhesion molecule 1 and LAMP-2, two highly glycosylated cellular proteins, presented an altered migration profile on SDS-PAGE in peripheral blood mononuclear cells from CS patients. RNA interference against VPS13B confirmed these glycosylation defects. Experiments with Brefeldin A demonstrated that intracellular retrograde cell trafficking was normal in CSfibroblasts. Furthermore, early endosomeswere almost absent in these cells and lysosomes were abnormally enlarged, suggesting a crucial role of VPS13B in endosomal-lysosomal trafficking. Our work provides evidence that CS is associated to a tissue-specific major defect of glycosylation and endosomal-lysosomal trafficking defect, suggesting that this could be a new key element to decipher the mechanisms of CS physiopathology. © The Author 2013. Published by Oxford University Press. All rights reserved.

Lemaitre J.-P.,CNRS Agroecology Lab | Duroux A.,CNRS Agroecology Lab | Pimpie R.,CNRS Agroecology Lab | Duez J.-M.,Plateau Technique de Biologie | Milat M.-L.,CNRS Agroecology Lab
Applied and Environmental Microbiology | Year: 2015

The detection of Listeria monocytogenes from food is currently carried out using a double enrichment. For the ISO methodology, this double enrichment is performed using half-Fraser and Fraser broths, in which the overgrowth of L. innocua can occur in samples where both species are present. In this study, we analyzed the induction of phages and phage tails of Listeria spp. in these media and in two brain heart infusion (BHI) broths (BHIM [bioMérieux] and BHIK [Biokar]) to identify putative effectors. It appears that Na2HPO4 at concentrations ranging from 1 to 40 g/liter with an initial pH of 7.5 can induce phage or phage tail production of Listeria spp., especially with 10 g/liter of Na2HPO4 and a pH of 7.5, conditions present in half-Fraser and Fraser broths. Exposure to LiCl in BHIM (18 to 21 g/liter) can also induce phage and phage tail release, but in half-Fraser and Fraser broths, the concentration of LiCl is much lower (3 g/liter). Low phage titers were induced by acriflavine and/or nalidixic acid. We also show that the production of phages and phage tails can occur in half-Fraser and Fraser broths. This study points out that induction of phages and phage tails could be triggered by compounds present in enrichment media. This could lead to a false-negative result for the detection of L. monocytogenes in food products. © 2015, American Society for Microbiology.

Broseus J.,Plateau Technique de Biologie | Visomblain B.,Plateau Technique de Biologie | Guy J.,Plateau Technique de Biologie | Maynadie M.,Plateau Technique de Biologie | Girodon F.,Plateau Technique de Biologie
International Journal of Laboratory Hematology | Year: 2010

Hereditary spherocytosis (HS) is a common red blood cell disorder. It has been shown that the mean sphered corpuscular volume (MSCV), an artificial volume, is always lower than the MCV in HS and also in some autoimmune haemolytic anaemia (AIHA). Our purpose was to assess the reliability of MSCV in routine practise, and its relevance in screening for HS. Comparison of MSCV and MCV was undertaken in a prospective study of 366 patients with anaemia. In addition, included were patients previously diagnosed to have HS (n = 33) or AIHA (n = 16). When MSCV was lower than MCV, a flow cytometric (FC) test for HS was performed. Delta (MCV-MSCV) values >9.6 fl were obtained for all HS patients. A wider spread of delta (MCV-MSCV) values was obtained for AIHA patients whose red cells gave FC test results negative for HS. In the ROC curve analysis, the determination of delta (MCV-MSCV) value has a 90.57% specificity and 100% sensitivity for HS. MSCV is a reliable automated parameter indicating possible HS. When a delta (MCV-MSCV) value is >9.6 fl, the FC test and the Coombs test are required in the differential diagnosis of HS and some AIHA. © 2010 Blackwell Publishing Ltd.

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