Random Active Shield

International audienceRecently, some active shielding techniques have been broken (e.g. by FlyLogic). The caveat is that their geometry is easy to guess, and thus they can be bypassed with an affordable price. This paper has two contributions. First of all, it provides a definition of the objectives of shielding, which is seldom found in publicly available sources. Notably, we precise the expected functionality, but also the constraints it must meet to be both manufacturable and secure. Second, we propose an innovative solution based on random shielding. The goal of this shielding is to make the geometry of the shield difficult to recognize, thereby making the ''identification'' phase of the attack harder than in previous schemes. Also, a proof of the shielding existence for two layers of metal is provided, which guarantees that the generation of the layout will succeed. Finally, we provide real tests of the shield generation algorithm, that show it is computationally tractable even for large areas to protect

Human granzyme B regulatory B cells prevent effector CD4+CD25- T cell proliferation through a mechanism dependent from lymphotoxin alpha

IntroductionHuman Granzyme B (GZMB) regulatory B cells (Bregs) have suppressive properties on CD4+ effector T cells by a mechanism partially dependent on GZMB. Moreover, these cells may be easily induced in vitro making them interesting for cell therapy.MethodsWe characterized this population of in vitro induced GZMB+Bregs using single cell transcriptomics. To investigate their regulatory properties, Bregs or total B cells were also co-cultured with T cells and scRNAseq was used to identify receptor ligand interactions and to reveal gene expression changes in the T cells.ResultsWe find that Bregs exhibit a unique set of 149 genes differentially expressed and which are implicated in proliferation, apoptosis, metabolism, and altered antigen presentation capacity consistent with their differentiated B cells profile. Notably, Bregs induced a strong inhibition of T cell genes associated to proliferation, activation, inflammation and apoptosis compared to total B cells. We identified and validated 5 receptor/ligand interactions between Bregs and T cells. Functional analysis using specific inhibitors was used to test their suppressive properties and we identified Lymphotoxin alpha (LTA) as a new and potent Breg ligand implicated in Breg suppressive properties.DiscussionWe report for the first time for a role of LTA in GZMB+Bregs as an enhancer of GZMB expression, and involved in the suppressive properties of GZMB+Bregs in human. The exact mechanism of LTA/GZMB function in this specific subset of Bregs remains to be determined

Étude des effets des contaminants chimiques de l'environnement chez les bivalves (approche de toxicogénomique fonctionnelle)

LE HAVRE-BU Centrale (763512101) / SudocSudocFranceF

Recherche des effets des contaminants chimiques sur le transcriptome de la moule zébrée (Dreissena polymorpha)

LE HAVRE-BU Centrale (763512101) / SudocSudocFranceF

Évaluation de l’intégrité de l’ADN des spermatozoïdes de crevettes Palaemon sp au moyen du test Comet : un outil pertinent pour la surveillance environnementale

International audienc

Évaluation de l’intégrité de l’ADN des spermatozoïdes de crevettes Palaemon sp au moyen du test Comet : un outil pertinent pour la surveillance environnementale

International audienc

Neuropeptide-Y in the trout brain and pituitary : localisation characterization and action on gonadotropin release

Using a specific antiserum raised against synthetic neuropeptide-Y (NPY), the distribution of NPY-like immunoreactivity in the brain and pituitary of the trout Oncorhynchus mykiss has been examined with the indirect immunofluorescence and peroxidase-antiperoxidase methods. The highest density of NPY-immunoreactive elements was found in the basal telencephalon and hypothalamus. In particular, NPY-immunoreactive neurons were located in the nucleus entopeduncularis and the preoptic nucleus. NPY-immunoreactive fibers were observed throughout the trout brain. The preoptic nucleus, the suprachiasmatic nucleus, and the nucleus entopeduncularis were densely innervated. In addition, NPY-positive fibers were detected in the nucleus lateralis tuberis and in the distal and intermediate lobes of the pituitary. The NPY-like peptide of the trout brain was characterized by combining HPLC analysis and radioimmunological detection. Serial dilutions of trout hypothalamus and pituitary extracts produced displacement curves that were parallel to the standard curve. HPLC analysis resolved a major peak which was slightly less hydrophobic than porcine NPY. The possible effect of NPY, either alone or in combination with a GnRH antagonist, on gonadotropin (GtH) release from trout pituitaries was investigated using a perifusion system technique