L’institut Marey, les dessous de l’histoire

Pour la communauté française des neurosciences, l’institut Marey, petit pavillon du début du siècle détruit en 1978, n’a pas encore livré tous ses mystères. Depuis les années 1900 jusqu’à la création en 1947 d’un institut du CNRS, plusieurs générations de chercheurs s’y sont succédé. Parmi eux, trois acteurs pionniers, que le Comité pour l’histoire du CNRS a eu l’honneur de rencontrer le 21 janvier 2000. Denise Albe-Fessard, Pierre Buser et Robert Naquet se livrent ici en toute liberté de ton. Extraits.For the French neurosciences community, the history of the Marey Institute is still a mystery. On the 21st of January 2000, the Committee for the history of CNRS met three pioneers of French neurosciences, Denise Albe-Fessard, Pierre Buser and Robert Naquet

Epilepsy Caused by an Abnormal Alternative Splicing with Dosage Effect of the SV2A Gene in a Chicken Model

Photosensitive reflex epilepsy is caused by the combination of an individual's enhanced sensitivity with relevant light stimuli, such as stroboscopic lights or video games. This is the most common reflex epilepsy in humans; it is characterized by the photoparoxysmal response, which is an abnormal electroencephalographic reaction, and seizures triggered by intermittent light stimulation. Here, by using genetic mapping, sequencing and functional analyses, we report that a mutation in the acceptor site of the second intron of SV2A (the gene encoding synaptic vesicle glycoprotein 2A) is causing photosensitive reflex epilepsy in a unique vertebrate model, the Fepi chicken strain, a spontaneous model where the neurological disorder is inherited as an autosomal recessive mutation. This mutation causes an aberrant splicing event and significantly reduces the level of SV2A mRNA in homozygous carriers. Levetiracetam, a second generation antiepileptic drug, is known to bind SV2A, and SV2A knock-out mice develop seizures soon after birth and usually die within three weeks. The Fepi chicken survives to adulthood and responds to levetiracetam, suggesting that the low-level expression of SV2A in these animals is sufficient to allow survival, but does not protect against seizures. Thus, the Fepi chicken model shows that the role of the SV2A pathway in the brain is conserved between birds and mammals, in spite of a large phylogenetic distance. The Fepi model appears particularly useful for further studies of physiopathology of reflex epilepsy, in comparison with induced models of epilepsy in rodents. Consequently, SV2A is a very attractive candidate gene for analysis in the context of both mono- and polygenic generalized epilepsies in humans

Torture Approval in Comparative Perspective

Torture is (almost) universally condemned as barbaric and ineffective, yet it persists in the modern world. What factors influence levels of support for torture? Public opinion data from 31 countries in 2006 and 2008 (a total of 44 country-years) are used to test three hypotheses related to the acceptability of torture. The findings, first, show that outright majorities in 31 country-years reject the use of torture. Multiple regression results show that countries with high per capita income and low domestic repression are less likely to support torture. Constraints on the executive have no significant effect on public opinion on torture

Vanin-1 pantetheinase drives increased chondrogenic potential of mesenchymal precursors in ank/ank mice.

International audienceWidespread endochondral and intramembranous ectopic bone formation is mediated by extracellular PP(i) deficiency that develops in ank/ank mice. Herein we report on the rapid condensation into chondrogenic nodules of cultured ank/ank bone marrow stromal cells (BMSCs). We compared the roles of increased chondrogenic potential versus altered osteoblast function in the ank/ank phenotype. To do so, we crossbred ank/ank mice with mice lacking Vanin-1 pantetheinase, which inhibits synthesis of the chondrogenesis regulator glutathione, since we observed increased Vanin-1 expression and pantetheinase activity and decreased glutathione in ank/ank BMSCs. Vnn1(-/-) BMSCs demonstrated delayed chondrogenesis mediated by increased glutathione. Moreover, increased chondrogenesis of ank/ank BMSCs and increased chondrogenic transdifferentiation and calcification by ank/ank aortic smooth muscle cells and explants were corrected by Vanin-1 knockout. Osteoblastogenesis was accelerated in ank/ank mesenchymal stem cells. However, in cultured ank/ank osteoblasts, Vanin-1 knockout actually increased specific alkaline phosphatase activity and lowered extracellular PP(i), and did not correct increased calcification. Moreover, Vanin-1 knockout failed to correct the ank/ank skeletal soft tissue phenotype. Therefore, ank/ank periskeletal soft tissue calcification appears more dependent on altered osteoblastic function than enhanced chondrogenic potential and is not dependent on Vanin-1; however, Vanin-1 regulates chondrogenesis via glutathione metabolism and is critical for accelerated chondrogenesis of ank/ank mesenchymal precursors and P(i) donor-driven chondrogenic transdifferentiation and calcification of aortic smooth muscle cells