Monitoring indoor air quality in French schools and day-care centres. Results from the first phase of a pilot survey

International audienceIndoor air quality surveillance in public premises, especially those hosting vulnerable populations such as children, was introduced in the second French national environment and health action plan and then regulated by the first "Grenelle Environnement" law, on August 3rd, 2009. A national pilot monitoring survey of indoor air quality in 310 French schools and day-care centres was performed in two phases from 2009 to 2011. The results of the first phase show that air quality is overall acceptable in 90% of the establishments with respect to the management values suggested by the French committee for public health. Nonetheless, a few cases required additional diagnoses or corrective measures. Furthermore, air stuffiness (based on CO2 measurements) was found to be very high in 16% of the classrooms. The Mayors and School Principals were informed and provided with means to identify the main sources of pollution and to implement remediation actions

Contribuer au Dictionnaire des antiquités grecques et romaines : quelques cas de figures

La mise en ligne et l’« actualisation » du Dictionnaire des antiquités invitent à une « autopsie » historiographique de l’entreprise initiée par Charles Daremberg (1817-1872), puis réalisée par Edmond Saglio (1828-1911) et Edmond Pottier (1855-1934) dans le dernier quart du xixe et le premier quart du xxe siècle . Lors d’un enseignement de master consacré aux « méthodes et courants de la recherche en histoire ancienne » à l’université de Toulouse II-Le Mirail, a été lancée en 2004-2005 l’idée..

Notch signaling via Hes1 transcription factor maintains survival of melanoblasts and melanocyte stem cells

Melanoblasts (Mbs) are thought to be strictly regulated by cell–cell interactions with epidermal keratinocytes, although the precise molecular mechanism of the regulation has been elusive. Notch signaling, whose activation is mediated by cell–cell interactions, is implicated in a broad range of developmental processes. We demonstrate the vital role of Notch signaling in the maintenance of Mbs, as well as melanocyte stem cells (MSCs). Conditional ablation of Notch signaling in the melanocyte lineage leads to a severe defect in hair pigmentation, followed by intensive hair graying. The defect is caused by a dramatic elimination of Mbs and MSCs. Furthermore, targeted overexpression of Hes1 is sufficient to protect Mbs from the elimination by apoptosis. Thus, these data provide evidence that Notch signaling, acting through Hes1, plays a crucial role in the survival of immature Mbs by preventing initiation of apoptosis

Both Monoclonal and Polyclonal Immunoglobulin Contingents Mediate Complement Activation in Monoclonal Gammopathy Associated-C3 Glomerulopathy

C3 glomerulopathy (C3G) results from acquired or genetic abnormalities in the complement alternative pathway (AP). C3G with monoclonal immunoglobulin (MIg-C3G) was recently included in the spectrum of “monoclonal gammopathy of renal significance.” However, mechanisms of complement dysregulation in MIg-C3G are not described and the pathogenic effect of the monoclonal immunoglobulin is not understood. The purpose of this study was to investigate the mechanisms of complement dysregulation in a cohort of 41 patients with MIg-C3G. Low C3 level and elevated sC5b-9, both biomarkers of C3 and C5 convertase activation, were present in 44 and 78% of patients, respectively. Rare pathogenic variants were identified in 2/28 (7%) tested patients suggesting that the disease is acquired in a large majority of patients. Anti-complement auto-antibodies were found in 20/41 (49%) patients, including anti-FH (17%), anti-CR1 (27%), anti-FI (5%) auto-antibodies, and C3 Nephritic Factor (7%) and were polyclonal in 77% of patients. Using cofactor assay, the regulation of the AP was altered in presence of purified IgG from 3/9 and 4/7 patients with anti-FH or anti-CR1 antibodies respectively. By using fluid and solid phase AP activation, we showed that total purified IgG of 22/34 (65%) MIg-C3G patients were able to enhance C3 convertase activity. In five documented cases, we showed that the C3 convertase enhancement was mostly due to the monoclonal immunoglobulin, thus paving the way for a new mechanism of complement dysregulation in C3G. All together the results highlight the contribution of both polyclonal and monoclonal Ig in MIg-C3G. They provide direct insights to treatment approaches and opened up a potential way to a personalized therapeutic strategy based on chemotherapy adapted to the B cell clone or immunosuppressive therapy

L’animal : un objet d’étude

Homo animal est : l’être humain appartient lui-même au règne animal, mais il est le seul à projeter sur les autres membres de ce vaste ensemble un regard analytique. Prendre l’animal comme objet d’étude, c’est le propre de l’homme. « Chez absolument tous il y a quelque chose de naturel, c’est-à-dire de beau » : Aristote, s’apprêtant à détailler les Parties des animaux, prévient son lecteur que les animaux les plus répugnants méritent eux aussi l’attention du scientifique, car ils témoignent des règles auxquelles se conforme la nature, que le philosophe a à cœur de percer. Cette longue tradition d’étude du monde animal, renouvelée aujourd’hui par les découvertes sur le génome, a pris de multiples formes au travers des âges ; mais elle a toujours suscité d’amples questionnements, non seulement sur la nature des animaux eux-mêmes, mais aussi, plus largement, sur leur place dans le monde et, en retour, sur celle de l’homme lui-même. Le Congrès national des sociétés historiques et scientifiques rassemble chaque année universitaires, membres de sociétés savantes et jeunes chercheurs. Ce recueil est issu de travaux présentés lors du 141e Congrès sur le thème « L’animal et l’homme »

C5b9 Deposition in Glomerular Capillaries Is Associated With Poor Kidney Allograft Survival in Antibody-Mediated Rejection

C4d deposition in peritubular capillaries (PTC) reflects complement activation in antibody-mediated rejection (ABMR) of kidney allograft. However, its association with allograft survival is controversial. We hypothesized that capillary deposition of C5b9—indicative of complement-mediated injury—is a severity marker of ABMR. This pilot study aimed to determine the frequency, location and prognostic impact of these deposits in ABMR. We retrospectively selected patients diagnosed with ABMR in two French transplantation centers from January 2005 to December 2014 and performed C4d and C5b9 staining by immunohistochemistry. Fifty-four patients were included. Median follow-up was 52.5 (34.25–73.5) months. Thirteen patients (24%) had C5b9 deposits along glomerular capillaries (GC). Among these, seven (54%) had a global and diffuse staining pattern. Twelve of the C5b9+ patients also had deposition of C4d in GC and PTC. C4d deposits along GC and PTC were not associated with death-censored allograft survival (p = 0.42 and 0.69, respectively). However, death-censored allograft survival was significantly lower in patients with global and diffuse deposition of C5b9 in GC than those with a segmental pattern or no deposition (median survival after ABMR diagnosis, 6 months, 40.5 months and 44 months, respectively; p = 0.015). Double contour of glomerular basement membrane was diagnosed earlier after transplantation in C5b9+ ABMR than in C5b9– ABMR (median time after transplantation, 28 vs. 85 months; p = 0.058). In conclusion, we identified a new pattern of C5b9+ ABMR, associated with early onset of glomerular basement membrane duplication and poor allograft survival. Complement inhibitors might be a therapeutic option for this subgroup of patients

Pollutions atmosphériques urbaines

Les oxydes d’azote (NOx) sont les principaux traceurs de la pollution automobile. Ils résultent d’une réaction entre l’azote et l’oxygène de l’air pendant la combustion du carburant. Depuis dix ans, sur l’estuaire, aucune tendance significative n’a pu être observée malgré un doublement de la circulation automobile des vingt dernières années. L’augmentation des émissions automobiles a, en effet, vraisemblablement été compensée par une réduction parallèle des émissions industrielles. NIVEAUX MO..

Fonction du complexe cadhérine/caténine dans les cellules épithéliales de la glande mammaire et dans le lignage mélanocytaire

Les cadhérines sont des glycoprotéines transmem- branaires impliquées dans l’adhérence, la signalisation, la prolifération et la différenciation. Dans cette revue, l’expression et la fonction des cadhérines sont décrites dans deux systèmes biologiques distincts, l’épithélium mammaire et le lignage mélanocytaire. Le développement de la glande mammaire représente un modèle de différenciation épithéliale in situ et le lignage mélanocytaire un modèle de différenciation non épithéliale (ou mésenchymateuse) associée à une migration importante des cellules de leur site d’origine vers les différents compartiments de la peau. Dans l’épithélium mammaire, la E-cadhérine, la cadhérine majoritaire exprimée, contrôle la morphogenèse et le maintien de la structure épithéliale. Dans le lignage mélanocytaire, l’expression de nombreuses cadhérines est strictement régulée au cours du développement et à l’âge adulte. Les fonctions spécifiques induites par l’expression de ces cadhérines sont très peu connues et représentent un défi pour les années futures