Molecular Spectrum of Autosomal Dominant Hypercholesterolemia in France

Autosomal Dominant Hypercholesterolemia (ADH), characterized by isolated elevation of plasmatic LDL cholesterol and premature cardiovascular complications, is associated with mutations in 3 major genes: LDLR (LDL receptor), APOB (apolipoprotein B) and PCSK9 (proprotein convertase subtilisin-kexin type 9). Through the French ADH Research Network, we collected molecular data from 1358 French probands from eleven different regions in France. Mutations in the LDLR gene were identified in 1003 subjects representing 391 unique events with 46.0% missense, 14.6% frameshift, 13.6% splice, and 11.3% nonsense mutations, 9.7% major rearrangements, 3.8% small in frame deletions/insertions, and 1.0% UTR mutations. Interestingly, 175 are novel mutational events and represent 45% of the unique events we identified, highlighting a specificity of the LDLR mutation spectrum in France. Furthermore, mutations in the APOB gene were identified in 89 probands and in the PCSK9 gene in 10 probands. Comparison of available clinical and biochemical data showed a gradient of severity for ADH-causing mutations: FH=PCSK9>FDB>‘Others’ genes. The respective contribution of each known gene to ADH in this French cohort is: LDLR 73.9%, APOB 6.6%, PCSK9 0.7%. Finally, in 19.0% of the probands, no mutation was found, thus underscoring the existence of ADH mutations located in still unknown genes. © 2010 Wiley-Liss, Inc

Ville et campagne de Fréjus romaine

En 2006, une fouille d’archéologie préventive, désignée sous le nom de « Villa Romana », a été réalisée dans le quartier de Villeneuve à Fréjus. Durant l’Antiquité il s’agit d’une zone périurbaine située entre la ville de Forum Iulii et le débouché de l’Argens. Connu depuis longtemps en raison de la présence d’un édifice thermal toujours en élévation, le quartier a été fouillé à plusieurs occasions et est interprété comme étant l’emplacement du camp de la flotte, établi après la bataille d’Actium. Celui-ci se transforme progressivement durant le Ier siècle apr. J.-C. en quartier suburbain au fur et à mesure que se développe Forum Iulii. Le secteur fouillé se situe dans la partie sud du camp, bordée par la mer durant les premiers temps de l’Antiquité. La fouille a permis de révéler la présence d’une plage aménagée. Les terrains ont ensuite été rapidement gagnés sur la mer, en raison d’une avancée rapide du littoral, que des études récentes ont permis de bien connaitre à Fréjus. Des jardins y sont alors aménagés. A partir du IIe siècle, cet espace est transformé en zone agricole, et constitue l’illustration de l’exploitation de la campagne aux portes de Fréjus, et cela, jusqu’à la fin de l’Antiquité. S’ensuit une longue période d’abandon de plusieurs siècles, avant que l’espace ne soit à nouveau voué à l’agriculture et ce jusqu’à l’orée des années soixante. Depuis, le développement de la ville actuelle de Fréjus a de nouveau transformé ce quartier en zone urbaine. Cet ouvrage, publié quelques années seulement après la fouille, présente l’ensemble des études archéologiques et paléoenvironnementales, réalisées à l’occasion de cette opération, largement pluridisciplinaire. Elles fournissent un contexte environnemental nouveau pour ce quartier antique et permettent de redéfinir un paysage à partir d’analyses bioarchéologiques et paléoécologiques récentes. L’étude de l’ensemble des mobiliers archéologiques est également présentée, en suivant la chronologie et l’évolution de ce quartier à travers l’Antiquité et l’époque moderne

Fourth International Workshop on Spoken Dialog Systems

These proceedings presents the state-of-the-art in spoken dialog systems with applications in robotics, knowledge access and communication. It addresses specifically: 1. Dialog for interacting with smartphones; 2. Dialog for Open Domain knowledge access; 3. Dialog for robot interaction; 4. Mediated dialog (including crosslingual dialog involving Speech Translation); and, 5. Dialog quality evaluation. These articles were presented at the IWSDS 2012 workshop

Natural Interaction with Robots, Knowbots and SmartphonesPutting Spoken Dialog Systems into Practice /

XVI, 397 p. 132 illus., 73 illus. in color.onlin

Nicotine Upregulates Its Own Receptors through Enhanced Intracellular Maturation

and Pierre Jean Corringer * The neuronal nAChRs subject to upregulation are CNRS URA D2182 Récepteurs et Cognition pseudosymmetrical heteropentameric ion channels re-Institut Pasteur sulting from the assembly of principal (α2, α3, α4, α6) 25 rue du Dr. Roux and complementary (β2, β4) subunits. At the concentra-75724 Paris Cedex 15 tions of nicotine found in the brain of smokers (low France micromolar range), the highly expressed α4β2 receptors display the highest level of upregulation (Nguyen et al., 2003). Since receptors containing the β2 subunits are the most important for nicotine self-administration Summary in mice (Picciotto et al., 1998), it is likely that their upregulation contributes to the long-term effect of Chronic exposure to nicotine elicits upregulation of chronic nicotine and potentially to nicotine addiction high-affinity nicotinic receptors in the smoker’s brain

Epigenetic Silencing of Lysyl Oxidase-Like-1 through DNA Hypermethylation in an Autosomal Recessive Cutis Laxa Case

International audienceWe have recently reported a case of cutis laxa caused by a fibulin-5 missense mutation (p.C217R). Skin fibroblasts from this individual showed an abnormal pattern of expression of several genes coding for elastic fiber-related proteins, including lysyl oxidase-like-1 (LOXL1). In this study we intended to elucidate the mechanism responsible for LOXL1 downregulation in these fibulin-5-mutant cells. We identified a proximal region (-442/-342) of the human LOXL1 promoter in which two binding sites for the transcription factor specific protein 1 (Sp-1) are required for gene activity in normal fibroblasts. Binding of Sp-1 to these sequences was dramatically reduced within cutis laxa cells, although Sp-1 expression was normal. Further analysis of the promoter sequence found increased methylation levels in cutis laxa cells compared with cells from unaffected individuals. When DNA methyltransferase activity was transiently inhibited in cutis laxa cells using the 5-aza-2'-deoxycytidine, we found a significant increase in LOXL1 expression. In conclusion, besides changes caused by the fibulin-5 mutation, LOXL1 gene regulation is affected by an epigenetic mechanism that can be reversed by an inhibitor of DNA methyltransferase activity. It is not yet known whether LOXL1 gene expression is affected in all cases of cutis laxa arising from fibulin-5 mutation

Nicotine upregulates its own receptors through enhanced intracellular maturation.

International audienceChronic exposure to nicotine elicits upregulation of high-affinity nicotinic receptors in the smoker's brain. To address the molecular mechanism of upregulation, we transfected HEK293 cells with human alpha4beta2 receptors and traced the subunits throughout their intracellular biosynthesis, using metabolic labeling and immunoprecipitation techniques. We show that high-mannose glycosylated subunits mature and assemble into pentamers in the endoplasmic reticulum and that only pentameric receptors reach the cell surface following carbohydrate processing. Nicotine is shown to act inside the cell and to increase the amount of beta subunits immunoprecipitated by the conformation-dependent mAb290, indicating that nicotine enhances a critical step in the intracellular maturation of these receptors. This effect, which also takes place at concentrations of nicotine found in the blood of smokers upon expression of alpha4beta2 in SH-SY5Y neuroblastoma cells, may play a crucial role in nicotine addiction and possibly implement a model of neural plasticity

Investigation of Genetic Relationships Between Hanseniaspora Species Found in Grape Musts Revealed Interspecific Hybrids With Dynamic Genome Structures

Hanseniaspora, a predominant yeast genus of grape musts, includes sister species recently reported as fast evolving. The aim of this study was to investigate the genetic relationships between the four most closely related species, at the population level. A multi-locus sequence typing strategy based on five markers was applied on 107 strains, confirming the clear delineation of species H. uvarum, H. opuntiae, H. guilliermondii, and H. pseudoguilliermondii. Huge variations were observed in the level of intraspecific nucleotide diversity, and differences in heterozygosity between species indicate different life styles. No clear population structure was detected based on geographical or substrate origins. Instead, H. guilliermondii strains clustered into two distinct groups, which may reflect a recent step toward speciation. Interspecific hybrids were detected between H. opuntiae and H. pseudoguilliermondii. Their characterization using flow cytometry, karyotypes and genome sequencing showed different genome structures in different ploidy contexts: allodiploids, allotriploids, and allotetraploids. Subculturing of an allotriploid strain revealed chromosome loss equivalent to one chromosome set, followed by an auto-diploidization event, whereas another auto-diploidized tetraploid showed a segmental duplication. Altogether, these results suggest that Hanseniaspora genomes are not only fast evolving but also highly dynamic

A p.C217R Mutation in Fibulin-5 from Cutis Laxa Patients Is Associated with Incomplete Extracellular Matrix Formation in a Skin Equivalent Model

International audienceCutis laxa (CL) is a rare genodermatosis, which is clinically and genetically heterogeneous. It is characterized by redundant, loose, sagging, and inelastic skin. In a consanguineous family from Lebanon with autosomal-recessive transmission, we identified a homozygous missense mutation (c.649T --> C; p.C217R) in the fibulin-5 gene (FBLN5), which was, to our knowledge, previously unreported. Small skin biopsies were performed, which permitted isolation of skin fibroblasts harboring this FBLN5 mutation; they exhibited a deficit in cell growth. A CL skin equivalent (CL-SE) model compared with control SE was successfully developed to define the behavior of CL fibroblasts in a three-dimensional model. There was increased cell death and a global extracellular matrix deficiency in the dermis of this CL-SE model, and a low level of the main elastic fiber expression. There was no basement membrane evident at the ultrastructural level, and type-VII collagen could not be detected at the histological level. This model reproduced some defects of the extracellular matrix and highlighted other defects, which occurred at the time of the basement membrane formation, which were not evident in skin from patients. This CL-SE model could be adapted to screen for therapeutically active molecules

Genetic characterization of the human relapsing fever spirochete Borrelia miyamotoi in vectors and animal reservoirs of Lyme disease spirochetes in France

Background: In France as elsewhere in Europe the most prevalent TBD in humans is Lyme borreliosis, caused by different bacterial species belonging to Borrelia burgdorferi sensu lato complex and transmitted by the most important tick species in France, Ixodes ricinus. However, the diagnosis of Lyme disease is not always confirmed and unexplained syndromes occurring after tick bites have become an important issue. Recently, B. miyamotoi belonging to the relapsing fever group and transmitted by the same Ixodes species has been involved in human disease in Russia, the USA and the Netherlands. In the present study, we investigate the presence of B. miyamotoi along with other Lyme Borreliosis spirochetes, in ticks and possible animal reservoirs collected in France. Methods: We analyzed 268 ticks (Ixodes ricinus) and 72 bank voles (Myodes glareolus) collected and trapped in France for the presence of DNA from B. miyamotoi as well as from Lyme spirochetes using q-PCR and specific primers and probes. We then compared the French genotypes with those found in other European countries. Results: We found that 3% of ticks and 5.55% of bank voles were found infected by the same B. miyamotoi genotype, while co-infection with other Lyme spirochetes (B. garinii) was identified in 12% of B. miyamotoi infected ticks. Sequencing showed that ticks and rodents carried the same genotype as those recently characterized in a sick person in the Netherlands. Conclusions: The genotype of B. miyamotoi circulating in ticks and bank voles in France is identical to those already described in ticks from Western Europe and to the genotype isolated from a sick person in The Netherlands. This results suggests that even though no human cases have been reported in France, surveillance has to be improved. Moreover, we showed that ticks could simultaneously carry B. miyamotoi and Lyme disease spirochetes, increasing the problem of co-infection in humans