CRISPR Typing and Subtyping for Improved Laboratory Surveillance of Salmonella Infections

Laboratory surveillance systems for salmonellosis should ideally be based on the rapid serotyping and subtyping of isolates. However, current typing methods are limited in both speed and precision. Using 783 strains and isolates belonging to 130 serotypes, we show here that a new family of DNA repeats named CRISPR (clustered regularly interspaced short palindromic repeats) is highly polymorphic in Salmonella. We found that CRISPR polymorphism was strongly correlated with both serotype and multilocus sequence type. Furthermore, spacer microevolution discriminated between subtypes within prevalent serotypes, making it possible to carry out typing and subtyping in a single step. We developed a high-throughput subtyping assay for the most prevalent serotype, Typhimurium. An open web-accessible database was set up, providing a serotype/spacer dictionary and an international tool for strain tracking based on this innovative, powerful typing and subtyping tool

Génétique de la coloration de la robe chez les bovins (contribution à l'étude du rôle des gènes de la famille tyrosinase)

These works belong to the research thematic related to the identification of specific molecular markers for each French cattle breeds. They consist in the study of the tyrosinase family genes and of the RAB38 gene.The cloning and the polymorphism study of the coding region of TYR, TYRP1, DCT, RAB38 genes show a very good conservation at the genomic and proteic levels with other species. No racial polymorphism correlated to a phenotype has been detected. However, the transcriptional study shows that highly variable expression levels could explain the coat color differences.Notably, a lack in TYRP1 expression seems to be characteristic of the e/e animals at the EXTENSION locus. These works also confirm the epistatic property of the SILVER allele specific to the Charolaise breedLIMOGES-BU Sciences (870852109) / SudocSudocFranceF

La contention en parodontologie (indications)

La mobilité dentaire est un des principaux motifs de consultation exprimé par le patient. Si la mobilité dentaire, le traumatisme occlusal et la maladie parodontale sont étroitement liées, leur relation reste encore aujourd'hui complexe. Ce manuscrit propose de suivre l'évolution des recherches depuis le début du XXème siècle jusqu'à aujourd'hui en analysant les différentes études animales puis humaines ayant observé l'influence du traumatisme occlusal sur l'initiation, la progression et le traitement de la maladie parodontale. Cette analyse permettra de mettre en avant l'évolution de la pensée scientifique sur le rôle du traumatisme et de déterminer et justifier les indications de prise en charge du traumatisme occlusal, de la mobilité dentaire et ainsi, de réfléchir sur la place de la contention. Aujourd'hui en parodontologie, la seule indication reconnue de la contention est le rétablissement de la fonction et du confort du patient après traitement de l'inflammation. D'autres études doivent être menées pour préciser son rôle dans la prévention et le traitement de la parodontite.NANTES-BU Médecine pharmacie (441092101) / SudocNANTES-Bib.Odontologie (441092219) / SudocSudocFranceF

Artisanat verrier dans les forêts du Tarn à l'époque moderne

International audienc

Artisanat verrier dans les forêts du Tarn à l'époque moderne

International audienc

Progressive acquisition of sperm storage potential in the chicken oviduct

National audienc

Characterization of chicken Sertoli cells in vitro

In the testis, Sertoli cells play a key physiological role in that they support, nourish, and protect germ cells. Because of the importance of Sertoli cells, several laboratories have established a culture system of Sertoli cells. These cultures have been well developed in mammalian species, but to our knowledge no purified avian Sertoli cells culture has been described. The aim of this study was to isolate avian Sertoli cells and to investigate their function using a chicken model in an in vitro test system. Immature chicken Sertoli cells in culture present morphology similar to that of mammalian cells and conserve expression of the specific Sertoli marker, anti-Mullerian hormone. Furthermore, in contrast to mammals, they express the 3 beta-hydroxysteroid dehydrogenase enzyme. Stimulation of Sertoli cells with ovine follicle-stimulating hormone rapidly activates the 3 main downstream signaling pathways of the follicle-stimulating hormone receptor: cyclic adenosine monophosphate/protein kinase A, phosphatidylinositol 3-kinase/Akt, and mitogen-activated protein kinase pathways. In vitro, Sertoli cells are able to secrete lactate and inhibin and have conserved the phagocytosis property. Finally, avian Sertoli cells present 3 interesting characteristics: they actively proliferate in vitro, can be passaged several times, and are suitable for freezing in nitrogen. A direct consequence of these properties is to use this cell culture test system as an alternative method to bird reprotoxicity studies