Michel Ragon et l’arbre de la connaissance

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Being repairable as one of the features of sustainable polymers for circular economy – Illustration for high performances thermoset matrices’

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Intranasally administrated fusion-inhibitory lipopeptides block SARS-CoV-2 infection in mice and enable long-term protective immunity

International audienceAbstract We have assessed antiviral activity and induction of protective immunity of fusion-inhibitory lipopeptides derived from the C-terminal heptad-repeat domain of SARS-CoV-2 spike glycoprotein in transgenic mice expressing human ACE2 (K18-hACE2). The lipopeptides block SARS-CoV-2 infection in cell lines and lung-derived organotypic cultures. Intranasal administration in mice allows the maintenance of homeostatic transcriptomic immune profile in lungs, prevents body-weight loss, decreases viral load and shedding, and protects mice from death caused by SARS-CoV-2 variants. Prolonged administration of high-dose lipopeptides has neither adverse effects nor impairs peptide efficacy in subsequent SARS-CoV-2 challenges. The peptide-protected mice develop cross-reactive neutralizing antibodies against both SARS-CoV-2 used for the initial infection and recently circulating variants, and are completely protected from a second lethal infection, suggesting that they developed SARS-CoV-2-specific immunity. This strategy provides an additional antiviral approach in the global effort against COVID-19 and may contribute to development of rapid responses against emerging pathogenic viruses

Aberration and self-reconstruction of zero-order Bessel beams in isolated and array format generated using positive and negative axicon lenses

International audienceBessel beam arrays, which can be created involving multiple axicons, diffractive elements, and interference effects, can experience several types of aberrations that distort their ideal characteristics, limiting their applications in microscopy, photonics, and material processing. For instance, Tilt aberration occurs when the individual axicons or optical elements in the Bessel beam array generation setup are misaligned or tilted relative to each other. This tilt can affect the beam's quality, focusing ability, and propagation characteristics. The present study experimentally investigated how any tilt associated with the axicon lens (of both positive and negative surface profile) affects the spatial characteristics of Bessel beams in isolated as well as in array formats. In particular, the aberration characteristics of [1x7] Bessel beam arrays of conical half-angle up to 11 degrees were studied. The spatial filtering of Bessel beam arrays was also demonstrated.</div

Decoding the nexus: branched-chain amino acids and their connection with sleep, circadian rhythms, and cardiometabolic health

International audienceThe sleep-wake cycle stands as an integrative process essential for sustaining optimal brain function and, either directly or indirectly, overall body health, encompassing metabolic and cardiovascular well-being. Given the heightened metabolic activity of the brain, there exists a considerable demand for nutrients in comparison to other organs. Among these, the branched-chain amino acids, comprising leucine, isoleucine, and valine, display distinctive significance, from their contribution to protein structure to their involvement in overall metabolism, especially in cerebral processes. Among the first amino acids that are released into circulation post-food intake, branched-chain amino acids assume a pivotal role in the regulation of protein synthesis, modulating insulin secretion and the amino acid sensing pathway of target of rapamycin. Branched-chain amino acids are key players in influencing the brain’s uptake of monoamine precursors, competing for a shared transporter. Beyond their involvement in protein synthesis, these amino acids contribute to the metabolic cycles of γ-aminobutyric acid and glutamate, as well as energy metabolism. Notably, they impact GABAergic neurons and the excitation/inhibition balance. The rhythmicity of branched-chain amino acids in plasma concentrations, observed over a 24-hour cycle and conserved in rodent models, is under circadian clock control. The mechanisms underlying those rhythms and the physiological consequences of their disruption are not fully understood. Disturbed sleep, obesity, diabetes, and cardiovascular diseases can elevate branched-chain amino acid concentrations or modify their oscillatory dynamics. The mechanisms driving these effects are currently the focal point of ongoing research efforts, since normalizing branched-chain amino acid levels has the ability to alleviate the severity of these pathologies. In this context, the Drosophila model, though underutilized, holds promise in shedding new light on these mechanisms. Initial findings indicate its potential to introduce novel concepts, particularly in elucidating the intricate connections between the circadian clock, sleep/wake, and metabolism. Consequently, the use and transport of branched-chain amino acids emerge as critical components and orchestrators in the web of interactions across multiple organs throughout the sleep/wake cycle. They could represent one of the so far elusive mechanisms connecting sleep patterns to metabolic and cardiovascular health, paving the way for potential therapeutic interventions

L'école éduque-t-elle aux émotions ?

International audienceL'école éduque-t-elle aux émotions ?L'école est le lieu de l'apprentissage par excellence, qu'il soit formel ou informel. On y apprend les mathématiques, les langues vivantes mais aussi comment se faire des ami•es, respecter l'autorité, trouver sa place dans un groupe... La majorité des relations sociales entre jeunes scolarisé•es ont lieu dans un établissement scolaire. L'école est un lieu de rencontre et de sociabilité privilégié. Les adultes de la communauté éducative jouent un rôle dans cette socia(bi)lisation, s'inquiétant lorsqu'un•e élève semble ne pas avoir d'ami•es et prenant parfois le rôle de médiateurices dans les conflits entre élèves. Dans l'imaginaire collectif, l'école est souvent perçue comme un lieu neutre, un décor où seules la transmission des savoirs et l'évaluation des compétences importent. Cette vision fait abstraction d'une dimension essentielle : l'école est aussi un espace de socialisation émotionnelle, un lieu où se forgent des valeurs, des attitudes et des représentations. En particulier, les cours de français, et plus encore l'étude des oeuvres littéraires, jouent un rôle insoupçonné dans l'éducation sentimentale des élèves. La classe est un lieu où se conjuguent apprentissages académiques et construction affective.</div

Religion et hérésies dans la pensée d’Antonio Gramsci

Prix Sormani de la Fondazione Istituto Gramsci de Turin 2024International audienceThis book explores the history and future of religion in the work and life of Antonio Gramsci. The pursuit of a secularism understood as the political translation of religious language underpins the formation of key Gramscian concepts and the content of his “philosophy of praxis”.Ce livre porte sur l’histoire et l’avenir des religions dans l’œuvre et la vie d’Antonio Gramsci. La recherche d’une laïcité comprise comme traduction politique des langages religieux conditionne la genèse des principaux concepts gramsciens et la teneur de sa « philosophie de la praxis »

Impact of psychedelics on craving in addiction: A systematic review

International audienceBackground: In the context of the need to increase treatment options for substance use disorders, recent research has evaluated the therapeutic potential of psychedelics. However, there is an incomplete understanding of psychedelics’ effects on craving, a core symptom of addictive disorders and a predictor of substance use and relapse. Aims: To determine if the use of psychedelics is associated with changes in craving in humans. Methods: A systematic review of the literature, using PubMed, PsycInfo, and Scopus databases up to May 2023. We included all studies assessing any substance craving levels after psychedelic use (protocol registration number CRD42021242856). Results: Thirty-eight published articles were included, corresponding to 31 studies and 2639 participants, pertaining either to alcohol, opioid, cocaine, or tobacco use disorders. Twelve of the 31 included studies reported a significant decrease in craving scores following psychedelic use. All but two studies had methodological issues, leading to moderate to high risk of bias scores. Conclusions: Some psychedelics may show promising anti-craving effects, yet the diversity and high risk of bias of extant studies indicate that these results are to be considered with caution. Further well-controlled and larger-scale trials should be encouraged

A case series examining the efficacy of gabapentin as a substitution therapy for the treatment of pregabalin use disorder

International audienceBackground: Gabapentinoids are ligands of a brain calcium channel, which are approved for different indications, including epilepsy, neuropathic pain, or generalized anxiety disorder. Among gabapentinoids, pregabalin has been increasingly associated with a risk of pregabalin use disorder (PUD). To date, there is no recommended medical treatment for PUD. However, gabapentin, which has a lower abuse potential, could be used as a substitution therapy to reduce pregabalin withdrawal and craving.Objectives: To report on the experimental use of high-dose gabapentin among those with PUD.Methods: case series of four patients (3 males and 1 female) with severe PUD (average daily doses ranging from 1,200 to 8,400 mg pregabalin), in whom high dose gabapentin was prescribed as a substitution treatment.Results: Upon gabapentin being administered as substitution therapy for pregabalin, all four patients experienced intense craving and distress. Despite receiving high doses of gabapentin, due to the observed levels of craving and distress, all four patients had to be rapidly switched back to pregabalin.Conclusions: Preliminary clinical findings suggest gabapentin is unlikely to be a suitable, lower-risk alternative treatment for people with PUD. Additional examination of candidate medications, including other gabapentinoids, could be useful to identify an effective treatment for PUD.</div