35 research outputs found
Late Pleistocene mammalian assemblages of Southeast Asia: New dating, mortality profiles and evolution of the predator-prey relationships in an environmental context
Karstic sites have great potential for yielding data regarding changes in faunal communities in the Pleistocene of Southeast Asia. In this region, the majority of fossil-bearing deposits are karstic breccias, which generally demonstrate a complicated sedimentary history. While most of the mammalian assemblages recovered in these deposits are only composed of isolated teeth, their study remains essential for reconstructing paleoecology and paleoclimatology of the region. We analyzed the assemblages recovered in three mainland and two insular karstic sites: Tam Hang South and Nam Lot in northern Laos, Duoi U'Oi in northern Vietnam, Punung in central Java and Sibrambang in western Sumatra and obtained new chronologies for three of these sites so that their significance could be discussed within their correct chronological context. The resulting age ranges place the sites in MIS5 and M1S4. The comparative analysis of the faunas, in terms of taphonomy, taxonomic diversity and abundance, and mortality profiles (Cervus unicolor, Sus scrofa, Sus vittatus, rhinocerotids and Tapirus indicus), reveals marked differences in prey-predators (carnivores and/or humans) relationships in relation to habitat. The study of homininesbearing sites (Punung, Nam Lot, Duoi U'Oi) allows us to emphasize different interactions with large carnivores (felids, hyaenids, canids). (C) 2015 Elsevier B.V. All rights reserved
Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study
Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008â11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003â13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 Ă 10â10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 Ă 10â8 DHFR p=8·37 Ă 10â7 MTRNR2L2 p=2·15 Ă 10â9) and to a lesser extent in REGISTRY (MSH3 p=9·36 Ă 10â4 DHFR p=8·45 Ă 10â4 MTRNR2L2 p=1·20 Ă 10â3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 Ă 10â8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16â0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06â0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation
MIAJ_RPLS_V2009_1 Programme de régression PLS avec ou sans sélection de variables (langage MATLAB)
Ăducation Ă la contraception chez l'adolescent (expĂ©rimentation au sein du LycĂ©e St-John Perse de Pau)
TOULOUSE3-BU Santé-Centrale (315552105) / SudocSudocFranceF
Taxonomic bias in biodiversity data and societal preferences
International audienceStudying and protecting each and every living species on Earth is a major challenge of the 21st century. Yet, most species remain unknown or unstudied, while others attract most of the public, scientific and government attention. Although known to be detrimental, this taxonomic bias continues to be pervasive in the scientific literature, but is still poorly studied and understood. Here, we used 626 million occurrences from the Global Biodiversity Information Facility (GBIF), the biggest biodiversity data portal, to characterize the taxonomic bias in biodiversity data. We also investigated how societal preferences and taxonomic research relate to biodiversity data gathering. For each species belonging to 24 taxonomic classes, we used the number of publications from Web of Science and the number of web pages from Bing searches to approximate research activity and societal preferences. Our results show that societal preferences, rather than research activity, strongly correlate with taxonomic bias, which lead us to assert that scientists should advertise less charismatic species and develop societal initiatives (e.g. citizen science) that specifically target neglected organisms. Ensuring that biodiversity is representatively sampled while this is still possible is an urgent prerequisite for achieving efficient conservation plans and a global understanding of our surrounding environment
Implication de DICER dans l'ulcération du mélanome chez le porc
Implication de DICER dans l'ulcération du mélanome chez le porc. Séminaire du Département de Génétique Animal
KIT and melanoma predisposition in pigs: sequence variants and association analysis
KIT mutations have been detected in different cancer subtypes, including melanoma. The gene also has been extensively studied in farm animals for its prominent role in coat color. The present work aimed at detecting KIT variants in a porcine model of cutaneous melanoma, the melanoblastoma-bearing Libechov Minipig (MeLiM). By sequencing exons and intron borders, 36 SNPs and one indel were identified. Of 10 coding SNPs, three were non-synonymous mutations, likely to affect the protein conformation. A promising variant, located in exon 19 (p.Val870Ala), was genotyped in a MeLiM Ă Duroc cross, and an association analysis was conducted on several melanoma-related traits. This variant showed a significant association with melanoma development, tumor ulceration and cutaneous invasion. In conclusion, although the KIT gene would not be a major causal gene for melanoma development in pig, its genetic variation could be influencing this trait