Custom human endogenous retroviruses dedicated microarray identifies self-induced HERV-W family elements reactivated in testicular cancer upon methylation control

Endogenous retroviruses (ERVs) are an inherited part of the eukaryotic genomes, and represent ∼400 000 loci in the human genome. Human endogenous retroviruses (HERVs) can be divided into distinct families, composed of phylogenetically related but structurally heterogeneous elements. The majority of HERVs are silent in most physiological contexts, whereas a significant expression is observed in pathological contexts, such as cancers. Owing to their repetitive nature, few of the active HERV elements have been accurately identified. In addition, there are no criteria defining the active promoters among HERV long-terminal repeats (LTRs). Hence, it is difficult to understand the HERV (de)regulation mechanisms and their implication on the physiopathology of the host. We developed a microarray to specifically detect the LTR-containing transcripts from the HERV-H, HERV-E, HERV-W and HERV-K(HML-2) families. HERV transcriptome was analyzed in the placenta and seven normal/tumoral match-pair samples. We identified six HERV-W loci overexpressed in testicular cancer, including a usually placenta-restricted transcript of ERVWE1. For each locus, specific overexpression was confirmed by quantitative RT-PCR, and comparison of the activity of U3 versus U5 regions suggested a U3-promoted transcription coupled with 5′R initiation. The analysis of DNA from tumoral versus normal tissue revealed that hypomethylation of U3 promoters in tumors is a prerequisite for their activation

Atypical/Nor98 Scrapie Infectivity in Sheep Peripheral Tissues

Atypical/Nor98 scrapie was first identified in 1998 in Norway. It is now considered as a worldwide disease of small ruminants and currently represents a significant part of the detected transmissible spongiform encephalopathies (TSE) cases in Europe. Atypical/Nor98 scrapie cases were reported in ARR/ARR sheep, which are highly resistant to BSE and other small ruminants TSE agents. The biology and pathogenesis of the Atypical/Nor98 scrapie agent in its natural host is still poorly understood. However, based on the absence of detectable abnormal PrP in peripheral tissues of affected individuals, human and animal exposure risk to this specific TSE agent has been considered low. In this study we demonstrate that infectivity can accumulate, even if no abnormal PrP is detectable, in lymphoid tissues, nerves, and muscles from natural and/or experimental Atypical/Nor98 scrapie cases. Evidence is provided that, in comparison to other TSE agents, samples containing Atypical/Nor98 scrapie infectivity could remain PrPSc negative. This feature will impact detection of Atypical/Nor98 scrapie cases in the field, and highlights the need to review current evaluations of the disease prevalence and potential transmissibility. Finally, an estimate is made of the infectivity loads accumulating in peripheral tissues in both Atypical/Nor98 and classical scrapie cases that currently enter the food chain. The results obtained indicate that dietary exposure risk to small ruminants TSE agents may be higher than commonly believed

LE CADMIUM RENAL (BIOINDICATEUR D'EXPOSITION DE LA FAUNE SAUVAGE, ETUDE PRATIQUE SUR DES POPULATIONS DE CHEVREUILS DU NORD-EST DE LA FRANCE)

REIMS-BU Santé (514542104) / SudocSudocFranceF

LES ENVENIMATIONS PROVOQUEES PAR LES MOLLUSQUES MARINS DU GENRE CONUS (FAMILLE DES CONIDAE)

REIMS-BU Santé (514542104) / SudocSudocFranceF

Les animaux marins venimeux de France métropolitaine présentant un risque par contact cutané

REIMS-BU Santé (514542104) / SudocSudocFranceF

L'homéopathie et le traitement du cheval de course

MONTPELLIER-BU Pharmacie (341722105) / SudocSudocFranceF

Le principe de précaution dans le domaine de l'environnement

REIMS-BU Santé (514542104) / SudocSudocFranceF

La centrale nucléaire de Chooz (08) (impacts environnementaux)

REIMS-BU Santé (514542104) / SudocSudocFranceF

Toxicité du manganèse pour le système nerveux chez l'homme exposé professionnellement ou par l'environnement

REIMS-BU Santé (514542104) / SudocSudocFranceF

ASPECTS TOXICOLOGIQUES DES FIBRES MINERALES ARTIFICIELLES SUBSTITUTS A L'AMIANTE

REIMS-BU Santé (514542104) / SudocSudocFranceF