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Recommandations pour la pratique clinique : prévention et prise en charge de l’infection par le virus varicelle zona (VZV) pendant la grossesse et la période périnatale (version longue)
No full textInternational audienceThe Société de Pathologie Infectieuse de Langue Française released in 2024 a new national recommendation for clinical practice on the prevention and management of varicella zoster virus (VZV) infection during pregnancy and the perinatal period.The previous recommendation was issued in 1998, at a time of anti-VZV immunoglobulins shortage; it has hence become obsolete.This recommendation is a formalized expert consensus focusing on infectious diseases management; it is drawn up by a multidisciplinary working group (infectiologists, obstetricians, pediatricians, microbiologists, midwives, hygienists).It has been endorsed by the Collège National des Gynécologues Obstétriciens Français, the Société Française de Médecine Périnatale, the Société Française de Néonatologie, the Collège des Sage-femmes, and the Groupe Infections et Périnatalité of the Société Française de Microbiologie.The aim of this article is to explain and recontextualize the elements of this recommendation.Une nouvelle recommandation nationale pour la pratique clinique sur la prévention et la prise en charge de l’infection par le virus varicelle zona (VZV) pendant la grossesse et la période périnatale est parue en 2024, sous l’égide de la Société de Pathologie Infectieuse de Langue Française.La précédente recommandation, publiée en 1998 pendant une période de pénurie en immunoglobulines spécifiques, était devenue en effet obsolète.Il s’agit d’un consensus formalisé d’experts élaboré par un groupe de travail multidisciplinaire (infectiologues, obstétriciens, pédiatres, microbiologistes, sage-femme, hygiénistes), dont le champ est infectiologique.Cette recommandation a été endossée par le Collège National des Gynécologues Obstétriciens Français, par la Société Française de Médecine Périnatale, par la Société Française de Néonatologie, par le collège des Sage-femmes, et par le Groupe Infections et Périnatalité de la Société Française de Microbiologie.L’objectif de cet article est d’expliciter, en les recontextualisant, les éléments de cette mise à jour
The role of l-serine and l-threonine in the energy metabolism and nutritional stress response of .
No full textInternational audiencel-Serine and l-threonine have versatile roles in metabolism. In addition to their use in protein synthesis, these amino acids participate in the biosynthesis pathways of other amino acids and even phospholipids. Furthermore, l-serine and l-threonine can be substrates for a serine/threonine dehydratase (Ser/ThrDH), resulting in pyruvate and 2-oxobutyrate, respectively, thus being amino acids with anaplerotic potential. , the etiological agent of Chagas disease, uses amino acids in several biological processes: metacyclogenesis, infection, resistance to nutritional and oxidative stress, osmotic control, etc. This study investigated the import and metabolism of l-serine, l-threonine, and glycine in . Our results demonstrate that these amino acids are transported from the extracellular environment into cells through a saturable transport system that fits the Michaelis-Menten model. Our results show that l-serine and l-threonine can sustain epimastigote cell viability under nutritional stress conditions and stimulate oxygen consumption, maintaining intracellular ATP levels. Additionally, our findings indicate that serine plays a role in establishing the mitochondrial membrane potential in . Serine is also involved in energy metabolism via the serine-pyruvate pathway, which stimulates the production and subsequent excretion of acetate and alanine. Our results demonstrate the importance of l-serine and l-threonine in the energy metabolism of and provide new insights into the metabolic adaptations of this parasite during its life cycle.IMPORTANCE, the parasite responsible for Chagas disease, impacts 5-6 million individuals in the Americas and is rapidly spreading globally due to significant human migration. This parasitic organism undergoes a complex life cycle involving triatomine insects and mammalian hosts, thriving in diverse environments, such as various regions within the insect's digestive tract and mammalian cell cytoplasm. Crucially, its transmission hinges on its adaptive capabilities to varying environments. One of the most challenging environments is the insect's digestive tract, marked by nutrient scarcity between blood meals, redox imbalance, and osmotic stresses induced by the triatomine's metabolism. To endure these conditions, has developed a remarkably versatile metabolic network enabling it to metabolize sugars, lipids, and amino acids efficiently. However, the full extent of metabolites this parasite can thrive on remains incompletely understood. This study reveals that, beyond conventional carbon and energy sources (glucose, palmitic acids, proline, histidine, glutamine, and alanine), three additional metabolites (serine, threonine, and glycine) play vital roles in the parasite's survival during starvation. Remarkably, serine and threonine directly contribute to ATP production through a serine/threonine dehydratase enzyme not previously described in . The significance of this metabolic pathway for the parasite's survival sheds light on how metabolic networks aid in its endurance under extreme conditions and its ability to thrive in diverse metabolic settings
Étude expérimentale du suivi électrique de la propagation de la mousse dans les milieux poreux : mesures de Polarisation Induite Spectrale (SIP) et de Réflectométrie dans le Domaine Temporel (TDR) dans une cuve 2D
No full textInternational audienceMonitoring subsurface processes during soil remediation is crucial for optimizing environmentalrestoration techniques. Geophysical tools, such as Spectral Induced Polarization (SIP) and TimeDomain Reflectometry (TDR), offer non-invasive methods for tracking these processes. This studyfocuses on the electrical monitoring of foam propagation in saturated porous media to enhanceremediation strategies for hydrocarbon-polluted aquifers.Aqueous foam, consisting of gas bubbles dispersed in a liquid phase containing surfactants, iswidely used in soil remediation due to its high viscosity and ability to act as a blocking, mobilizing,or vectorizing agent. Understanding the electrical properties of foam propagation is essential forevaluating its effectiveness in remediation processes.Our experiments were conducted in a 2D tank packed with 1 mm glass beads and saturated withtap water (400 μS/cm) Figure 1. The foam was generated using an anionic surfactant (SDS) andinjected into the tank at a gas fraction (quality) of 85% and a constant flow rate of 8 mL/min. TheSIP method was employed to measure complex electrical resistivity across frequencies rangingfrom 1.46 Hz to 187 Hz, while the TDR method was used to assess relative permittivity andelectrical conductivity at this frequency of 70MHz. Additionally, image monitoring was utilized toconvert optical densities into foam saturation values (Sf), providing a means to validate thegeophysical measurements.The results, (Figure 1, Figure 2), show that foam propagation causes significant changes indielectric permittivity and resistivity in regions affected by foam injection. For the central zone,Probe 13, the dielectric permittivity decreases by 63% (from ~19 to ~7), while resistivity increasesup to 6000% (~85 Ω.m to ~5100 Ω.m). In contrast, Near-Center zones, e.g. probe 12, showmoderate changes (~33% permittivity decrease, ~120% resistivity increase). Probes in the edgezones, such as Probe 11, show no significant changes in permittivity or resistivity, as the foampropagation did not reach these areas. This lack of variation validates that foam impact is confinedto the central and intermediate zones. The observed foam saturation from image analysisvalidates the geophysical measurements, with higher foam saturation (up to 90%) in the central zone correlating with greater electrical property changes. Additionally, we observe higher phaseshifts in Probe 13, Figure 3. We are further analyzing the phase-frequency variation (1.46 Hz to 20kHz) to better understand the polarization effects induced by foam.These findings highlight the potential of SIP and TDR methods for monitoring foam flow in porousmedia and provide valuable insights into the complex interactions between foam and electricalproperties. This study underscores the importance of integrating geophysical techniques withimage-based analysis to improve the understanding and effectiveness of soil remediationprocesses
Substrat idéologique des extrêmes droites
No full textInternational audienceThe aim of this communication is to isolate, beyond national particularities, the invariants in the discourse of the extreme right carried by the current leaders of these movements. Despite a few cosmetic expedients, the various extreme right-wing movements are always confronted with the obsession of an organic conception of the Nation.Cette communication a pour but d'isoler, au-delà des particularités nationales, , les invariants des discours des extrêmes droites portés par les dirigeants actuels de ces mouvements. Les différentes extrêmes droites, malgré quelques expédients cosmétique de façade, sont toujours confrontés à la permanence de l'obsession d'une conception organique de la Nation
Optimal Scheduling Algorithms for Software-Defined Radio Pipelined and Replicated Task Chains on Multicore Architectures
No full textInternational audienceSoftware-Defined Radio (SDR) represents a move from dedicated hardware to software implementations of digital communication standards. This approach offers flexibility, shorter time to market, maintainability, and lower costs, but it requires an optimized distribution tasks in order to meet performance requirements. Thus, we study the problem of scheduling SDR linear task chains of sateless and stateful tasks for streaming processing. We model this problem as a pipelined workflow scheduling problem based on pipelined and replicated parallelism on homogeneous resources. We propose an optimal dynamic programming solution and an optimal greedy algorithm named OTAC for maximizing throughput while also minimizing resource utilization. Moreover, the optimality of the proposed scheduling algorithm is proved. We evaluate our solutions and compare their execution times and schedules to other algorithms using synthetic task chains and an implementation of the DVB-S2 communication standard on the AFF3CT SDR Domain Specific Language. Our results demonstrate how OTAC quickly finds optimal schedules, leading consistently to better results than other algorithms, or equivalent results with fewer resources
Simulation of the Background from CO Reaction in the JUNO Scintillator
No full textInternational audienceLarge-scale organic liquid scintillator detectors are highly efficient in the detection of MeV-scale electron antineutrinos. These signal events can be detected through inverse beta decay on protons, which produce a positron accompanied by a neutron. A noteworthy background for antineutrinos coming from nuclear power reactors and from the depths of the Earth (geoneutrinos) is generated by () reactions. In organic liquid scintillator detectors, particles emitted from intrinsic contaminants such as U, Th, and Pb/Po, can be captured on C nuclei, followed by the emission of a MeV-scale neutron. Three distinct interaction mechanisms can produce prompt energy depositions preceding the delayed neutron capture, leading to a pair of events correlated in space and time within the detector. Thus, () reactions represent an indistinguishable background in liquid scintillator-based antineutrino detectors, where their expected rate and energy spectrum are typically evaluated via Monte Carlo simulations. This work presents results from the open-source SaG4n software, used to calculate the expected energy depositions from the neutron and any associated de-excitation products. Also simulated is a detailed detector response to these interactions, using a dedicated Geant4-based simulation software from the JUNO experiment. An expected measurable CO event rate and reconstructed prompt energy spectrum with associated uncertainties, are presented in the context of JUNO, however, the methods and results are applicable and relevant to other organic liquid scintillator neutrino detectors
Approche computationnelle pour le repositionnement de médicament au travers d’une perspective holistique avec les graphes de connaissances (OREGANO)
No full textDrug discovery is a long and costly process. Drug repositioning is a promising alternative which involves finding new indications for existing drugs. By comparing large quantities of information on drugs that have failed in the final phases of clinical trials, or that have been granted marketing authorization and are now on the market, it is possible to find candidate repositioning drugs capable of treating a condition for which they were not initially developed. To compare all these drugs, computational methods, based on large databases, are favored for their efficiency, speed and ability to analyze large quantities of information. Knowledge graphs are ideal structures for integrating this heterogeneous information. A knowledge graph organizes its information into triplets consisting of a subject, an object and a predicate explaining the relationship between the subject and the object. This graph, combined with embedding techniques (machine learning), can be used to predict new relationships between subjects and objects (which are nodes in the graph). It is therefore possible to transform the problem of repositioning into a problem of discovering new links in a graph. This thesis addresses these issues in the context of the OREGANO project, which aims to build a large knowledge graph on drugs and apply node-plotting techniques for drug repositioning. These techniques “project” the graph into a vector space where each entity is represented by a vector. One of OREGANO’s innovations is also to include data on natural compounds whose medicinal properties are exploited in many countries, and whose repositioning potential has been little explored. First, we present the way in which we designed the OREGANO knowledge graph, considering two distinct integration approaches. We then describe the evolutions that have been made to the graph over the years. Thirdly, we demonstrate the ability of the OREGANO knowledge graph to predict new links using embedding techniques. Predictions are evaluated with the usual metrics and empirically in the context of drug repositioning. The OREGANO graph as well as the algorithm and code developments are made available to the community at https://gitub.u-bordeaux.fr/erias/oregano.La découverte de médicaments est un processus long et coûteux. Le repositionnement de médicaments est une alternative prometteuse qui consiste à trouver de nouvelles indications pour des médicaments existants. En comparant de grandes quantités d’informations sur les médicaments qui ont échoué aux dernières phases des essais cliniques ou qui ont obtenu une autorisation de mise sur le marché, et donc commercialisés, il est possible de trouver des médicaments candidats au repositionnement capables de traiter une affection pour laquelle ils n’ont pas été développés initialement. Pour comparer tous ces médicaments, les méthodes computationnelles s’appuyant sur de grandes bases de données sont privilégiées pour leur efficacité, leur rapidité et leur capacité à croiser de grandes quantités d’informations. Les graphes de connaissances sont des structures appropriées pour intégrer ces informations de nature hétérogène. Un graphe de connaissances organise ces informations en triplets composés d’un sujet, d’un objet et d’un prédicat explicitant la relation entre le sujet et l’objet. Ce graphe, combiné à des techniques de plongement de nœuds (apprentissage automatique), permet de prédire de nouvelles relations entre sujets et objets (qui sont des nœuds du graphe). Il est donc possible de transformer le problème de repositionnement en un problème de découverte de nouveaux liens dans un graphe. Cette thèse s’intéresse à ces problématiques dans le cadre du projet OREGANO visant à construire un large graphe de connaissances sur les médicaments et à appliquer des techniques de plongement de nœuds pour le repositionnement de médicaments. Ces techniques "projettent" le graphe dans un espace vectoriel où chaque entité est représentée par un vecteur. Une des innovations apportées par OREGANO est également d’inclure des données sur des composés naturels dont les propriétés médicinales sont exploitées dans de nombreux pays et dont les potentialités de repositionnement ont été peu explorées. Dans un premier temps, nous présentons la manière dont nous avons conçu le graphe de connaissances OREGANO, en considérant deux approches d’intégration distinctes. Nous exposons ensuite les évolutions qui ont été apportées au graphe au fil des versions. Dans un troisième temps, nous exposons la capacité du graphe de connaissances OREGANO à prédire de nouveaux liens grâce à des techniques de plongement de nœuds. Les prédictions sont évaluées avec les métriques habituelles et empiriquement dans le cadre du repositionnement de médicaments. Le graphe OREGANO ainsi que les développements des algorithmes et du code sont disponibles pour la communauté scientifique à l’adresse suivante : https://gitub.u-bordeaux.fr/erias/oregano
Considérations historiques et épistémologiques autour de l’intercompréhension en Italie et dans la Gallo-Romania au prisme de la variation
No full textInternational audienc
High-throughput sequence-based microsatellite genotyping for the non-model Neotropical tree species Anadenanthera colubrina (Leguminosae)
No full textInternational audienceBackground and aims -Anadenanthera colubrina is a Neotropical native forest tree species with significant ecological importance in Seasonally Dry Tropical Forests. Developing genetic markers for this species is relevant for conservation, breeding, and evolutionary studies. Previously available genetic markers for A. colubrina consisted of a few microsatellites. Next-generation sequencing (NGS) strategies allow simple and cost-effective development of new SSR loci from lowcoverage whole genome shotgun sequencing. The main aim was to develop microsatellite markers for sequence-based high-throughput genotyping (SSRseq) in the species and to characterize their information content against traditional capillary electrophoresis-based microsatellite data by estimating the amount of molecularly accessible size homoplasy of each locus. Additionally, the reliability of these markers for population genetic analysis was assessed by genotyping two age classes (reproductively mature trees and seedlings) in a typical location in Argentina. Key results -Sixty primer pairs targeting microsatellites were designed, of which 25 were validated with allelic error rates < 3% and genotype missingness < 20%. A significantly higher number of alleles per locus and heterozygosity was detected for SSRseq considering sequence polymorphisms compared to analysing the same data based on sequence size (length) only. Size homoplasy, calculated as the proportion of mismatches between datasets relative to the number of alleles differing in length, averaged 97.85% over all SSR loci. High levels of population genetic diversity were detected in adults and seedlings from Paranaense forests, exceeding those reported in previous studies of A. colubrina using traditional SSRs. The generated datasets increase the resolution of capillary-based microsatellite genotyping, allowing for more accurate inference of eco-evolutionary processes in non-model tree species.</div