Formes et conditions de sortie de la vulnérabilité en milieux populaires

synthèse des recherche de l'équipe Formes et conditions d'entrée et de sortie de la "vulnérabilité" en milieux populaire

Maturation of B Cells in the Lamina Propria of Human Gut and Bronchi in the First Months of Human Life

Little is known of the maturation of the mucosae-associated lymphoid tissue (MALT) in man, because, for ethical reasons, tissues from newborns are not easy to obtain. We used the opportunity provided by autopsies systematically performed in infants who died of Sudden Infant Death Syndrome (SIDS) to study the maturation of the MALT after birth. Gut and bronchus samples of 90 infants from postpartum to 90 months and who died from SIDS were collected and studied by histological and immunofluorescence examination. Plasma cells, absent at birth, appeared within a few hours after birth and initially were of the IgM isotype. IgA plasma cells appeared at 12 days. These cells were first observed in gut and later in bronchi, indicating that maturation of the gut precedes that of bronchi. The number of plasma cells increased rapidly over time and IgA plasma cells became predominant after 3 weeks in the gut and 6 weeks in bronchi. At birth, only small IgM bearing B-cell foci were seen and organized germinal centers appeared to develop over a few days, first in the gut and only later in bronchi. These results confirm that, in man, the MALT organization at birth is still in its fetal form and that maturation depends on intestinal challenges and evolves over several weeks before IgA becomes the predominant isotype secreted

Applicabilité de la différentiation automatique à un système d'équations aux dérivées partielles régissant les phénomènes thermohydrauliques dans un tube chauffant

Dans ce rapport, nous étudions l'applicabilité de la différentiation automatique à un système d'équations aux dérivées partielles régissant les phénomènes thermohydrauliques dans un tube chauffant. En particulier, il s'agit de voir si le différentiateur Odyssée développé à l'INRIA dans le projet SAFIR peut différentier un code tel que Thyc-1D  (maquetteà une dimension en espace du code Thyc), lequel comporte 23 sous-routines de calcul. Resume AN |The applicability of automatic differentiation on a set of partial differential equations governing thermohydraulic phenomena in heat exchangers is examined. More specifically, the challenge is to differentiate the code Thyc-1D, a 1-D mockup of the 3-D code Thyc implementing these equations, with the automatic differentiator Odyssée with as few manual interventions as possible. The code to differentiate contains 23 routines, including linear solvers and black-box functions, whose code is not availabl

Follicular Proinflammatory Cytokines and Chemokines as Markers of IVF Success

Cytokines are key modulators of the immune system and also contribute to regulation of the ovarian cycle. In this study, Bender MedSystems FlowCytomix technology was used to analyze follicular cytokines (proinflammatory: IL-1β, IL-6, IL-18, IFN-γ, IFN-α, TNF-α, IL-12, and IL-23;, and anti-inflammatory: G-CSF), chemokines (MIP-1α, MIP-1β, MCP-1, RANTES, and IL-8), and other biomarkers (sAPO-1/Fas, CD44(v6)) in 153 women undergoing in vitro fertilization (IVF). Cytokine origin was studied by mRNA analysis of granulosa cells. Higher follicular MIP-1α and CD44(v6) were found to correlate with polycystic ovary syndrome, IL-23, INF-γ, and TNF-α with endometriosis, higher CD44(v6) but lower IL-β and INF-α correlated with tubal factor infertility, and lower levels of IL-18 and CD44(v6) characterized unexplained infertility. IL-12 positively correlated with oocyte fertilization and embryo development, while increased IL-18, IL-8, and MIP-1β were associated with successful IVF-induced pregnancy

A Soluble Form of the Triggering Receptor Expressed on Myeloid Cells-1 Modulates the Inflammatory Response in Murine Sepsis

The triggering receptor expressed on myeloid cells (TREM)-1 is a recently discovered receptor expressed on the surface of neutrophils and a subset of monocytes. Engagement of TREM-1 has been reported to trigger the synthesis of proinflammatory cytokines in the presence of microbial products. Previously, we have identified a soluble form of TREM-1 (sTREM-1) and observed significant levels in serum samples from septic shock patients but not controls. Here, we investigated its putative role in the modulation of inflammation during sepsis. We observed that sTREM-1 was secreted by monocytes activated in vitro by LPS and in the serum of animals involved in an experimental model of septic shock. Both in vitro and in vivo, a synthetic peptide mimicking a short highly conserved domain of sTREM-1 appeared to attenuate cytokine production by human monocytes and protect septic animals from hyper-responsiveness and death. This peptide seemed to be efficient not only in preventing but also in down-modulating the deleterious effects of proinflammatory cytokines. These data suggest that in vivo modulation of TREM-1 by sTREM peptide might be a suitable therapeutic tool for the treatment of sepsis

Review. Divergent selection for residual feed intake in the growing pig

To view supplementary material for this article, please visit https:/doi.org/10.1017/S175173111600286XThis review summarizes the results from the INRA (Institut National de la Recherche Agronomique) divergent selection experiment on residual feed intake (RFI) in growing Large White pigs during nine generations of selection. It discusses the remaining challenges and perspectives for the improvement of feed efficiency in growing pigs. The impacts on growing pigs raised under standard conditions and in alternative situations such as heat stress, inflammatory challenges or lactation have been studied. After nine generations of selection, the divergent selection for RFI led to highly significant ( P<0.001) line differences for RFI (−165 g/day in the low RFI (LRFI) line compared with high RFI line) and daily feed intake (−270 g/day). Low responses wereobserved on growth rate (−12.8 g/day, P <0.05) and body composition (+0.9mm backfat thickness, P = 0.57; −2.64% lean meat content, P<0.001) with a marked response on feed conversion ratio (−0.32 kg feed/kg gain, P<0.001). Reduced ultimate pH and increased lightness of the meat ( P<0.001) were observed in LRFI pigs with minor impact on the sensory quality of the meat. These changes in meat quality were associated with changes of the muscular energy metabolism. Reduced maintenance energy requirements (−10% after five generations of selection) and activity (−21% of time standing after six generations of selection) of LRFI pigs greatly contributed to the gain in energy efficiency. However, the impact of selection for RFI on the protein metabolism of the pig remains unclear. Digestibility of energy and nutrients was not affected by selection, neither for pigs fed conventional diets nor for pigs fed high-fibre diets. A significant improvement of digestive efficiency could likely be achieved by selecting pigs on fibre diets. No convincing genetic or blood biomarker has been identified for explaining the differences in RFI, suggesting that pigs have various ways to achieve an efficient use of feed. No deleterious impact of the selection on the sow reproduction performance was observed. The resource allocation theory states that low RFI may reduce the ability to cope with stressors,via the reduction of a buffer compartment dedicated to responses to stress. None of the experiments focussed on the response of pigs to stress or challenges could confirm this theory. Understanding the relationships between RFI and responses to stress and energy demanding processes, as such immunity and lactation, remains a major challenge for a better understanding of the underlying biological mechanisms of the trait and to reconcile the experimental results with the resource allocation theory