Entrapment and traumatic neuropathies of the elbow and hand: An imaging approach

AbstractUltrasound and magnetic resonance imaging currently offer a detailed analysis of the peripheral nerves. Compressive and traumatic nerve injuries are the two main indications for imaging investigation of nerves with several publications describing the indications, technique and diagnostic capabilities of imaging signs. Investigation of entrapment neuropathies has three main goals, which are to confirm neuronal distress, search for the cause of nerve compression and exclude a differential diagnosis on the entire nerve. For traumatic nerve injuries, imaging, predominantly ultrasound, occasionally provides essential information for management including the type of nerve lesion, its exact site and local extension

Aggregation dynamics and identification of aggregation-prone mutants of the von Hippel-Lindau tumor suppressor protein

International audienceQuality control mechanisms promote aggregation and degradation of misfolded proteins. In budding yeast, the human von Hippel-Lindau protein (pVHL, officially known as VHL) is misfolded and forms aggregates. Here, we investigated the aggregation of three pVHL isoforms (pVHL213, pVHL160, pVHL172) in fission yeast. The full-length pVHL213 isoform aggregates in highly dynamic small puncta and in large spherical inclusions, either close to the nucleus or to the cell ends. The large inclusions contain the yeast Hsp104 chaperone. Aggregate clearance is regulated by proteasomal degradation. The pVHL160 isoform forms dense foci and large irregularly shaped aggregates. In silico, prediction of pVHL aggregation propensity identified a key aggregation-promoting region within exon 2. Consistently, the pVHL172 isoform, which lacks exon 2, formed rare reduced inclusions. We studied the aggregation propensity of pVHL variants harbouring missense mutations found in kidney carcinomas. We show that the P86L mutation stimulated small aggregate formation, the P146A mutation increased large inclusion formation, whereas the I151S mutant destabilized pVHL. The prefoldin subunit Pac10 (the human homolog VBP-1 binds to pVHL) is required for pVHL stability. Reduction of soluble functional pVHL might be crucial in VHL-related diseases

Genetic diversity of canine olfactory receptors

<p>Abstract</p> <p>Background</p> <p>Evolution has resulted in large repertoires of olfactory receptor (OR) genes, forming the largest gene families in mammalian genomes. Knowledge of the genetic diversity of olfactory receptors is essential if we are to understand the differences in olfactory sensory capability between individuals. Canine breeds constitute an attractive model system for such investigations.</p> <p>Results</p> <p>We sequenced 109 OR genes considered representative of the whole OR canine repertoire, which consists of more than 800 genes, in a cohort of 48 dogs of six different breeds. SNP frequency showed the overall level of polymorphism to be high. However, the distribution of SNP was highly heterogeneous among OR genes. More than 50% of OR genes were found to harbour a large number of SNP, whereas the rest were devoid of SNP or only slightly polymorphic. Heterogeneity was also observed across breeds, with 25% of the SNP breed-specific. Linkage disequilibrium within OR genes and OR clusters suggested a gene conversion process, consistent with a mean level of polymorphism higher than that observed for introns and intergenic sequences. A large proportion (47%) of SNP induced amino-acid changes and the Ka/Ks ratio calculated for all alleles with a complete ORF indicated a low selective constraint with respect to the high level of redundancy of the olfactory combinatory code and an ongoing pseudogenisation process, which affects dog breeds differently.</p> <p>Conclusion</p> <p>Our demonstration of a high overall level of polymorphism, likely to modify the ligand-binding capacity of receptors distributed differently within the six breeds tested, is the first step towards understanding why Labrador Retrievers and German Shepherd Dogs have a much greater potential for use as sniffer dogs than Pekingese dogs or Greyhounds. Furthermore, the heterogeneity in OR polymorphism observed raises questions as to why, in a context in which most OR genes are highly polymorphic, a subset of these genes is not? This phenomenon may be related to the nature of their ligands and their importance in everyday life.</p

Mechanical characterization of a tribollayer created by high temperature fretting wear in a ceramic/metal alloy contact

In aeronautics, the blade disk contact, between ceramic and Haynes 25 (cobalt-based alloy) surfaces, is submitted to fretting oscillations, at high temperature, the fretting being an oscillatory movement (at the micrometer order) between two surfaces in contact. This contact has been modeled in the laboratory, showing high friction and wear at temperatures lower than 500°C whereas a sudden decrease of the friction coefficient, and negligible wear is observed above this threshold temperature. The cause of high friction and wear at low temperature was explained in previous paper [1]. At temperatures higher than 500°C, low friction and wear are linked to the formation of a third body, named glaze layer, or tribolayer, this layer being created by compacted and sintered debris, and adhering on both parts, the thickness being between 5-20µm. Its structure and chemical composition was studied in a previous paper [2]. However, understanding the mechanical properties responsible of the glaze layer lubricious properties is still a challenge. In this presentation, the mechanical properties of the Glaze Layer, measured as a function of the temperature, will be presented, and compared to its tribological properties. The HS25/ceramic fretting contact has been studied, in flat/flat and cross cylinders’ configuration, at temperatures higher than 500°C, in order to create the glaze layer. The mechanical characterization of the tribolayer and the HS25 was performed through nanoindentation and in situ SEM microcompression experiments as a function of the temperature, in the temperature domain where the glaze layer is performant and in the temperature domain where friction and wear are important, the tests being performed in the cross section. The first part of the presentation will be focused on the tribological contacts presentation, and micromechanical devices used description. Then, the glaze layer microstructure, chemical composition and mechanical properties will be detailed and discussed. Finally, a comparison between the mechanical properties and tribological properties of the glaze layer will be detailed [3]. This work was supported by the LABEX MANUTECH-SISE (ANR-10-LABX-0075) of University of Lyon, within the program “Investissements d’Avenir” (ANR-11-IDEX-0007) operated by the French National Research Agency (ANR). [1] A. Dreano, S. Fouvry, G. Guillonneau, A tribo-oxidation abrasive wear model to quantify the wear rate of a cobalt-based alloy subjected to fretting in low-to-medium temperature conditions, Tribol. Int. 125 (2018) 128–140. doi:10.1016/j.triboint.2018.04.032. [2] A. Viat, M.-I. De Barros Bouchet, B. Vacher, T. Le Mogne, S. Fouvry, J.-F. Henne, Nanocrystalline glaze layer in ceramic-metallic interface under fretting wear, Surface and Coatings Technology. 308 (2016) 307–315. doi:10.1016/j.surfcoat.2016.07.100. [3] A. Viat, G. Guillonneau, S. Fouvry, G. Kermouche, S. Sao Joao, J. Wehrs, J. Michler, J.-F. Henne, Brittle to ductile transition of tribomaterial in relation to wear response at high temperatures, Wear. 392 (2017) 60–68. doi:10.1016/j.wear.2017.09.015

Coat colour in dogs: identification of the Merle locus in the Australian shepherd breed

BACKGROUND: Coat colours in canines have many natural phenotypic variants. Some of the genes and alleles involved also cause genetic developmental defects, which are also observed in humans and mice. We studied the genetic bases of the merle phenotype in dogs to shed light on the pigmentation mechanisms and to identify genes involved in these complex pathways. The merle phenotype includes a lack of eumelanic pigmentation and developmental defects, hearing impairments and microphthalmia. It is similar to that observed in microphthalmia mouse mutants. RESULTS: Taking advantage of the dog as a powerful genetic model and using recently available genomic resources, we investigated the segregation of the merle phenotype in a five-generation pedigree, comprising 96 sampled Australian shepherd dogs. Genetic linkage analysis allowed us to identify a locus for the merle phenotype, spanning 5.5 megabases, at the centromeric tip of canine chromosome 10 (CFA10). This locus was supported by a Lod score of 15.65 at a recombination fraction θ = 0. Linkage analysis in three other breeds revealed that the same region is linked to the merle phenotype. This region, which is orthologous to human chromosome 12 (HSA12 q13-q14), belongs to a conserved ordered segment in the human and mouse genome and comprises several genes potentially involved in pigmentation and development. CONCLUSION: This study has identified the locus for the merle coat colour in dogs to be at the centromeric end of CFA10. Genetic studies on other breeds segregating the merle phenotype should allow the locus to be defined more accurately with the aim of identifying the gene. This work shows the power of the canine system to search for the genetic bases of mammalian pigmentation and developmental pathways

Le Conquet – Structures d’estran sur les îles Quéménès, Trielen et Béniguet

Après la succession de tempêtes sur les côtes atlantiques entre fin décembre 2013 et début janvier 2014, celles qui se sont déroulées au mois de février ont représenté le paroxysme des épisodes tempétueux hivernaux. La tempête sans nom, du 31 janvier au 3 février 2014, a eu lieu lors des marées de vives eaux équinoxiales (entre 101 et 114 de coefficient), puis lors de la tempête Petra (du 4 au 5 février, avec de 71 à 94 de coefficient), la hauteur maximale des vagues mesurées au phare des Pie..

Le Conquet – Structures d’estran sur l’île de Quéménès

Une intervention a eu lieu en mars 2014 sur un amas coquillier (site 22 bis) découvert par les tempêtes de l’hiver 2014 sur l’île de Quéménès (OA 2463). Cette première opération s’était arrêtée au pied de la microfalaise et avait mis au jour, outre les restes fauniques (faune terrestre, ichtyofaune, malacofaune, avifaune, mammifères marins), des restes anthracologiques et carpologiques et du mobilier céramique et lithique, l’ensemble se rattachant à la Protohistoire. À la fin de l’interventio..

Montaigne dans les bibliothèques privées en France au XVIIIe siècle

Dréano Chanoine. Montaigne dans les bibliothèques privées en France au XVIIIe siècle. In: Cahiers de l'Association internationale des études francaises, 1962, n°14. pp. 255-262

Charge d'entraînement et programme de compétition pour la saison 1997 (Élite homme). Évolution pour la période 1998-2000

Dréano Patrick. Charge d'entraînement et programme de compétition pour la saison 1997 (Élite homme). Évolution pour la période 1998-2000. In: Les Cahiers de l'INSEP, n°24, 1999. 2e Congrès international de triathlon de l’INSEP – 2nd INSEP international triathlon Congress pp. 112-120

Markus Messling, Les Hiéroglyphes de Champollion. Philologie et conquête du monde

Le déchiffrement des hiéroglyphes par Jean-François Champollion (1790-1832) constitue selon Markus Messling, auteur de cet ouvrage, un moment essentiel pour la philologie européenne du XIXe siècle ainsi que pour l'environnement politique, intellectuel et colonial qui la voit naître. Voici le point de départ de ce texte succinct et bien documenté, qui évite un nouveau portrait de Champollion en génie, et cherche davantage à retracer les péripéties européennes de l'écriture hiéroglyphique. Se d..