Le gisement paléolithique multistratifié « les Bossats » à Ormesson (Seine-et-Marne, France) : palethnographie ou pâle ethnographie ? Une synthèse des huit premières années de fouille (2009-2016)

editorial reviewedÀ l'évidence, ces vingt dernières années ont vu en France, notamment, se développer en parallèle deux nouvelles façons de traiter le Paléolithique supérieur ancien qui ne sont pas antagonistes d'ailleurs. L'une consiste en une reprise des stratigraphies anciennes dans le Centre et le Sud-Ouest de la France plus spécifiquement et est associée à une meilleure redéfinition des entités culturelles par l'analyse détaillée des différentes composantes des systèmes techniques. L'autre s'efforce d'appliquer à cette période la démarche palethnographique, inféodée historiquement au Magdalénien du Bassin parisien. Il est vrai que peu de gisements autorisaient ce type d'approche, en raison d'une surface fouillée insuffisante ou d'un état de conservation médiocre, mais même lorsque les découvertes s'y prêtaient, le manque de temps et d'investissement freinait également toute velléité d'une étude approfondie des sites en question, qui aurait alors débouché sur une lecture palethnographique des lieux et des artefacts. À l'issue d'un PCR mené entre 1999 et 2005, nous pouvions ainsi légitimement nous demander si nous étions capables de jouer les ethnologues du passé pour le Paléolithique supérieur ancien dans le Bassin parisien. Les sites identifiés dans le cadre de ce programme de recherche étaient certes nombreux mais représentés surtout par des découvertes de surface, ils ne garantissaient pas un niveau d'analyse digne de ce qui a pu se faire depuis plus de 50 ans à Pincevent ou à Étiolles par exemple (Bodu et al., 2013). Il aura fallu attendre la découverte fortuite du gisement de plein-air d'Ormesson « les Bossats » (Seine-et-Marne, près de Nemours) au début des années 2000 pour que cette question trouve une réponse positive. Concernant, au départ, presqu'exclusivement des vestiges lithiques et osseux attribués au Gravettien, les premières fouilles menées en 2009 permirent d'identifier rapidement un second niveau d'occupation, d'attribution moustérienne. Les campagnes suivantes amenèrent à la découverte de cinq autres niveaux d'occupation paléolithiques, inégaux tant pour la surface couverte que pour l'état de conservation : un second niveau moustérien résultant vraisemblablement de palimpsestes, un ensemble châtelperronien, un autre solutréen, un quatrième badegoulien et enfin entre Châtelperronien et Gravettien, un foyer isolé sans vestiges archéologiques associés. Cette stratigraphie paléolithique de plein-air dilatée est le témoignage d'une forte occupation du lieu pendant près de 30 000 ans, ce qui s'explique notamment par la configuration particulière de la vallée à cet endroit. À la diversité chronologique des occupations préhistoriques répond une diversité des comportements économiques et techniques au sein des différentes sphères d'activités mais également des habitudes spatiales différentes. À l'issue des huit premières années de fouille (2009-2016), le site d'Ormesson « les Bossats » permet ainsi de développer une approche détaillée des comportements techniques, économiques, spatiaux de groupes culturels distincts ayant vécu durant 30 000 ans dans un cadre géomorphologique et plus globalement naturel, relativement identique. Dépassant le jeu de mot facile « palethnographie ou pâle ethnographie ? » à Ormesson « les Bossats », nous proposons ici quelques éléments de réponse

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

"Un noeud de vipères archétypologique" lecture durandienne du roman Le Noeud de Vipères de François Mauriac

Le titre du roman de François Mauriac : Le Nœud de Vipères revient cinq fois dans la narration, toujours à des moments cruciaux. L’expression "nœud de vipères", maintenant lexicalisée, désigne une famille, un groupe divisé par la cupidité. Or dans ce roman ce n’est pas une expression toute faite qui résumerait globalement la famille haïssable de Louis, le personnage principal du roman, car la formule est décomposée, l’image élargie : en effet pendant toute sa confession, Louis nous parle des ..

[Prevention of deep venous thrombosis in medical care].

International audienceVenous thromboembolism is a frequent and potentially severe ailment in medical patients; the clinical signs are unreliable and as early detection of the thrombosis process by non-invasive techniques is not available, prevention appears to be an alternative. Careful definition of the medical situations at risk from venous thromboembolism is necessary. Age, prior history of venous thromboembolism, and immobilization constitute high risk circumstances. Analysis of the published studies advocates prevention in three circumstances: myocardial infarction, stroke and intensive care. In other cases, further controlled studies, randomized versus placebo, are needed

Hfe Gene Knock-Out in a Mouse Model of Hereditary Hemochromatosis Affects Bodily Iron Isotope Compositions

International audienceHereditary hemochromatosis is a genetic iron overload disease related to a mutation within the HFE gene that controls the expression of hepcidin, the master regulator of systemic iron metabolism. The natural stable iron isotope composition in whole blood of control subjects is different from that of hemochromatosis patients and is sensitive to the amount of total iron removed by the phlebotomy treatment. The use of stable isotopes to unravel the pathological mechanisms of iron overload diseases is promising but hampered by the lack of data in organs involved in the iron metabolism. Here, we use Hfe (-/-) mice, a model of hereditary hemochromatosis, to study the impact of the knock-out on iron isotope compositions of erythrocytes, spleen and liver. Iron concentration increases in liver and red blood cells of Hfe (-/-) mice compared to controls. The iron stable isotope composition also increases in liver and erythrocytes, consistent with a preferential accumulation of iron heavy isotopes in Hfe (-/-) mice. In contrast, no difference in the iron concentration nor isotope composition is observed in spleen of Hfe (-/-) and control mice. Our results in mice suggest that the observed increase of whole blood isotope composition in hemochromatosis human patients does not originate from, but is aggravated by, bloodletting. The subsequent rapid increase of whole blood iron isotope composition of treated hemochromatosis patients is rather due to the release of hepatic heavy isotope-enriched iron than augmented iron dietary absorption. Further research is required to uncover the iron light isotope component that needs to balance the accumulation of hepatic iron heavy isotope, and to better understand the iron isotope fractionation associated to metabolism dysregulation during hereditary hemochromatosis

Association between IgM anticardiolipin antibodies and deep venous thrombosis in patients without systemic lupus erythematosus.

International audiencePatients with systemic lupus erythematosus (SLE) are at risk of developing deep venous thrombosis (DVT). Should anticardiolipin antibodies (aCL) be detectable, this risk is significantly raised, particularly when these autoanti-bodies are cofactor-dependent. We conducted a cross-sectional study of consecutive unselected outpatients referred for clinical suspicion of DVT, as an attempt to address the following questions: firstly, were aCL antibodies associated with DVT in non-SLE patients? Secondly, was this association related to the cofactor dependence? From March 1992 to February 1994, 208 patients were enrolled in the study. Venography was positive in 110 patients (DVT patients), while the diagnosis of DVT could not be confirmed in the remaining 98 (referred to as disease controls). ACL was measured by ELISA, for IgG and IgM isotypes in two ways: fetal calf serum or bovine serum albumin were used as blocking agents to distinguish between cofactor-dependent and cofactor-independent antibodies. Positive aCL was defined as optical density (OD) values greater than the 95th percentile of OD distribution of 60 healthy controls. We found a high frequency of positive IgG aCL antibodies in both DVT patients and in disease controls (25.5 vs 23.5%). We suggest an association between IgM aCL and DVT. This association was, however, not dependent on the cofactor requirement

The value of a risk factor analysis in clinically suspected deep venous thrombosis.

International audienceBACKGROUND: The value of a risk factor analysis in the presence of a clinically suspected deep venous thrombosis (DVT) has been assessed mainly in inpatient populations. The aim of this prospective study was to evaluate the potential association between DVT and acquired circumstances suspected as risk factors, in a cohort of outpatients with a clinically suspected DVT. METHODS: Consecutive outpatients referred for a clinically suspected DVT, with recent clinical signs, not exceeding 1 week, were included. Before venography, all patients were interviewed by a trained physician to detect the presence of risk factors. RESULTS: From March 1992 to February 1994, 277 patients were included; venography was positive in 162 (58.4%). Five independent variables were significantly associated with the occurrence of DVT; in a multivariate analysis, 64.7% of patients were correctly classified; odds ratios for having DVT in the presence of these underlying conditions were respectively: 1.75 for age over 65 years, 1.68 for prior history of venous thromboembolism, 1.69 for high risk circumstances (any type of surgery or leg trauma within the past 3 months), 5.59 for malignancy, and 2.56 for varicose veins. CONCLUSIONS: In outpatients referred for a clinically suspected DVT, recognition of associated conditions might increase the certainty of the diagnosis

Natural and synthetic STAT3 inhibitors reduce hepcidin expression in differentiated mouse hepatocytes expressing the active phosphorylated STAT3 form.

International audienceDuring the inflammatory process, hepcidin overexpression favours the development of anaemia of chronic diseases which represents the second most common form of anaemia worldwide. The identification of therapeutic agents decreasing hepcidin expression is therefore an important goal. The aim of this study was to target the STAT3 signalling involved in the development of increased hepcidin expression related to chronic inflammation. In a co-culture model associating mouse hepatocytes and rat liver epithelial cells, the mRNA levels of hepcidin1, albumin, aldolase B, Cyp3a4, Stat3, Smad4 and iron regulatory genes were measured by real-time PCR. STAT3 and phosphorylated SMAD1/5/8 proteins were analysed by Western blot. At variance of hepatocyte pure culture, co-culture provided high levels of hepcidin1 mRNA, reaching 400% of the freshly isolated hepatocyte values after 6 days of culture. Hepcidin expression was associated with the maintenance of hepatocyte phenotype, STAT3 phosphorylation and functional BMP/SMAD pathway. Stat3 siRNAs inhibited the hepcidin1 mRNA expression. STAT3 inhibitors, including curcumin, AG490 and a peptide (PpYLKTK), reduced hepcidin1 mRNA expression even when cells were additionally exposed to IL-6. Hepcidin1 mRNA was expressed at high levels by hepatocytes in the co-culture model, and STAT3 pathway activation was controlled through STAT3 inhibitors. Such inhibitors could be useful to prevent anaemia related to hepcidin overexpression during chronic inflammation

Hepcidin induction limits mobilisation of splenic iron in a mouse model of secondary iron overload.

International audienceVenesection has been proposed as a treatment for hepatic iron overload in a number of chronic liver disorders that are not primarily linked to mutations in iron metabolism genes. Our aim was to analyse the impact of venesection on iron mobilisation in a mouse model of secondary iron overload. C57Bl/6 mice were given oral iron supplementation with or without phlebotomy between day 0 (D0) and D22, and the results were compared to controls without iron overload. We studied serum and tissue iron parameters, mRNA levels of hepcidin1, ferroportin, and transferrin receptor 1, and protein levels of ferroportin in the liver and spleen. On D0, animals with iron overload displayed elevations in iron parameters and hepatic hepcidin1 mRNA. By D22, in the absence of phlebotomies, splenic iron had increased, but transferrin saturation had decreased. This was associated with high hepatic hepcidin1 mRNA, suggesting that iron bioavailability decreased due to splenic iron sequestration through ferroportin protein downregulation. After 22days with phlebotomy treatments, control mice displayed splenic iron mobilisation that compensated for the iron lost due to phlebotomy. In contrast, phlebotomy treatments in mice with iron overload caused anaemia due to inadequate iron mobilisation. In conclusion, our model of secondary iron overload led to decreased plasma iron associated with an increase in hepcidin expression and subsequent restriction of iron export from the spleen. Our data support the importance of managing hepcidin levels before starting venesection therapy in patients with secondary iron overload that are eligible for phlebotomy