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High-affinity autoreactive plasma cells disseminate through multiple organs in patients with immune thrombocytopenic purpura
No full textInternational audienceThe major therapeutic goal for immune thrombocytopenia (ITP) is to restore normal platelet counts using drugs to promote platelet production or by interfering with mechanisms responsible for platelet destruction. 80% of patients possess anti-integrin αIIbβ3 (GPIIbIIIa) IgG autoantibodies causing platelet opsonization and phagocytosis. The spleen is considered the primary site of autoantibody production by autoreactive B cells and platelet destruction. The immediate failure in ~50% of patients to recover a normal platelet count after anti-CD20 Rituximab-mediated B cell depletion and splenectomy suggest that autoreactive, rituximab-resistant, IgG-secreting B cells (IgG-SC) reside in other anatomical compartments. We analyzed >3,300 single IgG-SC from spleen, bone marrow and/or blood of 27 patients with ITP revealing high inter-individual variability in affinity for GPIIbIIIa with variations over 3 logs. IgG-SC dissemination and range of affinities were however similar per patient. Longitudinal analysis of autoreactive IgG-SC upon treatment with anti-CD38 mAb daratumumab demonstrated variable outcomes, from complete remission to failure with persistence of high-affinity anti-GPIIbIIIa IgG-SC in the bone marrow. This study demonstrates the existence and dissemination of high-affinity autoreactive plasma cells in multiple anatomical compartments of patients with ITP that may cause the failure of current therapies
Hydrological variability and suspended particulate matter in the middle river Niger bassin
No full textInternational audienceIn the Sahel, climate variability and high population growth have led to changes in surface conditions that resulted in increased runoff coefficients and discharge in the major Sahelian rivers. The mid reaches of the Niger river have experienced significant increases in the Red flood, or local flood, that occurs during the rainy season between June and September, relative to Black flood, or Guinean flood that arrives in Niamey from December onwards.The objective of this work was to characterize suspended particulate matter (SPM) during the Red and Black floods in the Niamey area and analyse their spatio-temporal dynamics. Two approaches are used : the first one consists of regular in-situ measurements of SPM concentration and in their physical and mineral characterization by electron microscopy; the second is based on monitoring water color by both in-situ and satellite (Sentinel 2) radiometric measurements.SPM are characterized by very fine particles (with a major mode around 0.1-0.2 micrometers) mainly composed by kaolinites (iron oxides are also observed during the Red flood). This, combined with the very high levels of SPM concentration reached during the rainy season, results in very high values of reflectance in the visible end infrared bands. Radiometric measurements in the nir band by both the in-situ SKYE sensor and the Sentinel2 sensor are found to be significantly correlated to in-situ SPM, allowing efficient monitoring of SPM concentration in time and space.SPM-discharge curves, reveal a complex relationship : SPM increases very rapidly at the beginning of the rainy season when soils are washed out after the long dry period, reaching a peak before the first discharge peak (Red flood). SPM continues to decrease during the second discharge peak (Black flood) from December to February, providing a distinct and unique signature. Analysis of satellite data allowed identifying the main sources of SPM and to quantify the significant contribution of the right bank river tributaries to sediments in the middle Niger river bassin. This contribution may further increase in the context of global changes (climate and anthropogenic) with important consequences on sediment transport but also on water quality and bacterial concentration which are strongly influenced by high SPM
Vendre ses produits d’occasion, c’est aussi faire de la logistique (et ce n’est pas toujours drôle)
No full textÉcrire à l'encre violette: Littératures lesbiennes en France de 1900 à nos jours
No full textInternational audienceAprès des siècles d’un silence quasi-entier, plusieurs œuvres ouvertement lesbiennes sont publiées au tout début du XXe siècle. Depuis lors, des années folles à l’après-guerre, de l’histoire militante des années 1970 à la naissance de l’édition spécialisée, jusqu’à l’effervescence du début du XXIe siècle, ce sont des centaines de textes qui disent et théorisent leur existence. Parcourant tous les genres, ils mettent en scène le lesbianisme, nomment et nourrissent une culture partagée, en réactivent la mémoire et les noms.Né du constat d’une mémoire immense, mais enterrée, éclatée et négligée, Écrire à l’encre violette souhaite rendre compte de l’ampleur de ce dialogue lesbien : il intègre et modifie le cadre de la littérature, ouvre d’autres perspectives en bousculant ses normes
Etude du processus d'enseignement-apprentissage pour les notions de droites et de plans dans l'espace en Belgique : comment repenser la formation des enseignants ?
No full textInternational audienc
ARAB N. (dir) (2022), Innovation, expérimentation, rationalisation. Analyse comparée des scènes collectives d’innovation urbaine (SCIN). Le cas de la Métropole de Lyon. 203p..
No full textFusogenicity and neutralization sensitivity of the SARS-CoV-2 Delta sublineage AY.4.2
No full textInternational audienceBackground: SARS-CoV-2 lineages are continuously evolving. As of December 2021, the AY.4.2 Delta sub-lineage represented 20 % of sequenced strains in the UK and had been detected in dozens of countries. It has since then been supplanted by Omicron. The AY.4.2 spike displays three additional mutations (T95I, Y145H and A222V) in the N-terminal domain when compared to the original Delta variant (B.1.617.2) and remains poorly characterized.Methods: We compared the Delta and the AY.4.2 spikes, by assessing their binding to antibodies and ACE2 and their fusogenicity. We studied the sensitivity of an authentic AY.4.2 viral isolate to neutralizing antibodies.Findings: The AY.4.2 spike exhibited similar binding to all the antibodies and sera tested, and similar fusogenicity and binding to ACE2 than the ancestral Delta spike. The AY.4.2 virus was slightly less sensitive than Delta to neutralization by a panel of monoclonal antibodies; noticeably, the anti-RBD Imdevimab showed incomplete neutralization. Sensitivity of AY.4.2 to sera from vaccinated individuals was reduced by 1.3 to 3-fold, when compared to Delta.Interpretation: Our results suggest that mutations in the NTD remotely impair the efficacy of anti-RBD antibodies. The spread of AY.4.2 was not due to major changes in spike fusogenicity or ACE2 binding, but more likely to a partially reduced neutralization sensitivity
II. Les notions – La conception extensive de la notion de marché public en droit de l'Union européenne
No full textInternational audience(CJUE, 28 mai 2020, aff. C-796/18, ISE mbH c/ ville de Cologne, AJ contrat 2020. 394, obs. O. Villemagne ; RTD eur. 2021. 419, obs. A. Lawrence Durviaux, notion de marché public : hypothèse d'une coopération entre pouvoirs adjudicateurs ; coopération entre pouvoirs adjudicateurs : conditions d'existence et obligation de respecter le principe d'égalité de traitement
Spring colonies of the ant Temnothorax nylanderi tolerate cadmium better than winter colonies, in both a city and a forest habitat
No full textInternational audienceA recent study showed that, in the ant Temnothorax nylanderi, city colonies are more tolerant to cadmium than forest colonies. However, because of annual variation in biological factors (e.g. body size, anti-stress protein production or trace metal accumulation rate), trace metal tolerance may vary over the year. We aimed at testing whether tolerance to cadmium of colonies of T. nylanderi differs between two different seasons within the same year (winter and spring). We also assessed whether the better cadmium tolerance of city colonies was constant over these two different time points. We collected colonies at the end of their hibernation period (winter colonies) and several weeks after (spring colonies) from two different habitats (forest and city) to assess whether response to cadmium was consistent regardless of the environment. We exposed colonies to a cadmium or a control treatment for 61 days. We compared tolerance to cadmium between spring/winter and city/forest colonies by measuring several life history traits. We found that spring colonies tolerates cadmium better than winter colonies, and that city colonies have a higher tolerance to cadmium but only in spring. Although further studies with replicated pairs of city/forest habitats and different years will be necessary to confirm those results, our study suggests that tolerance to trace metals can fluctuate along the yearly cycle