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The whole blood oxylipin response : a new tool to assess and understand the inflammatory response to various immune stimuli in humans
No full textPrésentation oraleInternational audienceOxylipins are major immunomodulating mediators, yet studies of inflammation focus mainly on cytokines. Here, using a standardized whole-blood stimulation system, we characterized the oxylipin-driven inflammatory responses to various stimuli and their relationships with cytokine responses. We performed a pilot study in 25 healthy individuals using 6 different stimuli: 2 bacterial stimuli (LPS and live BCG), 2 viral stimuli (vaccine-grade poly I:C and live H1N1 attenuated influenza), an enterotoxin superantigen and a Null control. All stimuli induced a strong production of oxylipins but most importantly, bacterial, viral, and T cell immune responses show distinct oxylipin signatures. Integration of the oxylipin and cytokine responses for each condition revealed new immune networks improving our understanding of inflammation regulation. Finally, the oxylipin responses and oxylipin-cytokine networks were compared in patients with active tuberculosis or with latent infection. This revealed different responses to BCG but not LPS stimulation highlighting new regulatory pathways for further investigations
Inactivation of cytidine triphosphate synthase 1 prevents fatal auto-immunity in mice
No full textInternational audienceDe novo synthesis of the pyrimidine, cytidine triphosphate (CTP), is crucial for DNA/RNA metabolism and depends on the CTP synthetases, CTPS1 and −2. Partial CTPS1 deficiency in humans has previously been shown to lead to immunodeficiency, with impaired expansion of T and B cells. Here, we examine the effects of conditional and inducible inactivation of Ctps1 and/or Ctps2 on mouse embryonic development and immunity. We report that deletion of Ctps1 , but not Ctps2 , is embryonic-lethal. Tissue and cells with high proliferation and renewal rates, such as intestinal epithelium, erythroid and thymic lineages, activated B and T lymphocytes, and memory T cells strongly rely on CTPS1 for their maintenance and growth. However, both CTPS1 and CTPS2 are required for T cell proliferation following TCR stimulation. Deletion of Ctps1 in T cells or treatment with a CTPS1 inhibitor rescued Foxp3 -deficient mice from fatal systemic autoimmunity and reduced the severity of experimental autoimmune encephalomyelitis. These findings support that CTPS1 may represent a target for immune suppression
A ritual murder shaped the Early and Middle Neolithic across Central and Southern Europe
No full textInternational audienceIn the Rhône Valley’s Middle Neolithic gathering site of Saint-Paul-Trois-Châteaux (France), the positioning of two females within a structure aligned with the solstices is atypical. Their placement (back and prone) under the overhang of a silo in front of a third in a central position suggests a ritualized form of homicidal ligature strangulation. The first occurrence dates back to the Mesolithic, and it is from the Early Neolithic of Central Europe that the practice expands, becoming a sacrificial rite associated with an agricultural context in the Middle Neolithic. Examining 20 cases from 14 sites spanning nearly two millennia from Eastern Europe to Catalonia reveals the evolution of this ritual murder practice
Entretien avec Emmanuel Henry (IRISSO - Université Paris-Dauphine - PSL)
No full textCe portrait fait partie d'une série d'entretiens avec des figures importantes du champ des études sur l'ignorance.Entretien avec Emmanuel Henry, professeur de sociologie à l'Université Paris-Dauphine et chercheur à l'Institut de recherche interdisciplinaire en sciences sociales IRISSO UMR 7170-1427 (CNRS - Univ. Paris Daupine-PSL-INRAE) mené par Mathias Girel, le 19 décembre 2023 à l'École normale supérieure de Paris
Considérations sur la période d’activité d’Apsyrtos, hippiatre grec
No full textInternational audienceThis article concerns Apsyrtos, who wrote a veterinary work in the form of letters addressed to some 70 persons whom he listed. Determining the date of this military author, who inspired all later Greco-Latin hippiatric scholars, is very important in order to establish the dates of other hippiatric authors and, more generally, to better circumscribe the development of hippiatry in Late Antiquity. This study is assessment of the data obtained from third-party sources and also from the work of this hippiatrist, from the recipients of his letters or from the work of certain hippiatrists directly linked to him. A new estimate of the period of Apsyrtos' activity is thus established in the first half of the 4th century.Cet article concerne Apsyrtos, qui a écrit un ouvrage vétérinaire sous forme de lettres adressées à quelques 70 personnes qu’il nomme. La datation de cet auteur militaire, qui a inspiré toute la littérature hippiatrique gréco-latine ultérieure, est très importante pour la datation des autres auteurs hippiatres et, de façon plus générale, pour mieux circonscrire le développement de l’hippiatrie dans l’Antiquité tardive. Cette étude propose un état des lieux des renseignements tirés de sources tierces et aussi de l’œuvre de cet hippiatre, de destinataires de ses lettres ou encore de l’œuvre de certains hippiatres en lien direct avec lui. Une nouvelle datation de la période d’activité d’Apsyrtos est ainsi établie à la première moitié du IVe siècle
Cooperative self-assembly process involving giant toroidal polyoxometalate as a membrane building block in nanoscale vesicles
No full textInternational audienceThe self-assembly of organic amphiphilic species into various aggregates such as spherical or elongated micelles, cylinders up to the formation of lyotropic hexagonal or lamellar phases results from cooperative processes orchestrated by hydrophobic effect, while those involving ionic inorganic polynuclear entities and non-ionic organic components are still intriguing. Herein, we report on the supramolecular behavior of giant toroidal molybdenum blue-type polyoxometalate (POM), namely the {Mo} species in the presence of n-octyl--glucoside (C8G1), widely used as surfactant in biochemistry. Structural investigations were carried out using a set of complementary multiscale methods including single-crystal X-ray diffraction analysis supported by molecular modelling, small-angle X-ray scattering (SAXS), and cryo-TEM observations. In addition, liquid NMR, viscosimetry, surface tension measurement, and isothermal titration calorimetry (ITC) provided further information to decipher the complex aggregation pathway. Elucidation of the assembly process reveals a rich scenario where the presence of the large {Mo} anion disrupts the selfassembly of the C8G1, well-known to produce micelles, and induces striking successive phase transitions from fluid-to-gel and from gel-to-fluid. Herein, intimate organic-inorganic primary interactions arising from the super-chaotropic nature of the {Mo154} lead to versatile nanoscopic hybrid C8G1-{Mo} aggregates including crystalline discrete assemblies, smectic lamellar liquid crystals, and large uni-or multilamellar vesicles where the large torus {Mo} type POM acts a trans-membrane component
Données nouvelles sur l'histoire de Larsa (II)
No full textInternational audienceCette étude fait le point sur ce que les textes récemment publiés, découverts sur le site de Larsa lors de pillages ou depuis 2019 dans le cadre de la reprise des foulles régulières, nous apprennent sur l'histoire de Larsa dans le premier quart du IIe millénaire
