Défendre la démocratie directe : sur quelques arguments antidémocratiques des élites suisses

Plus que jamais, l'actualité mondiale ou nationale met en question le pouvoir du peuple. Là il se révolte avec fracas. Ici on le voit voter contre les autorités en place. Pour les uns il reconquiert sa liberté. Pour les autres il est aveugle et crée le désordre. Voici donc un livre sur le pouvoir. Dans la tradition de Benjamin Constant ou d'Alexis de Tocqueville, Antoine Chollet confère du souffle à l'examen des fondamentaux. Comment comprendre et articuler la liberté, l'égalité, la responsabilité, l'opposition entre une élite dite éclairée et les masses. En Suisse, quels sont les atouts exceptionnels, les dérives ou les illusions de la démocratie directe? Mal comprise elle est souvent confondue avec les libertés communales du Moyen Age. Ou admise avec des réserves suspectes. L'auteur en appelle à plus de rigueur et, fort de ses convictions, conclut par des appréciations sévères sur la politique suisse. Il décèle dans ses élites des tendances clairement antidémocratiques. Et inversement, il expose les raisons d'une confiance renforcée en l'institution même de la démocratie directe.

MRI monitoring of focal cerebral ischemia in peroxisome proliferator-activated receptor (PPAR)-deficient mice.

Peroxisome proliferator-activated receptors (PPARs) are a potential target for neuroprotection in focal ischemic stroke. These nuclear receptors have major effects in lipid metabolism, but they are also involved in inflammatory processes. Three PPAR isotypes have been identified: alpha, beta (or delta) and gamma. The development of PPAR transgenic mice offers a promising tool for prospective therapeutic studies. This study used MRI to assess the role of PPARalpha and PPARbeta in the development of stroke. Permanent middle cerebral artery occlusion induced focal ischemia in wild-type, PPARalpha-null mice and PPARbeta-null mice. T(2)-weighted MRI was performed with a 7 T MRI scan on day 0, 1, 3, 7 and 14 to monitor lesion growth in the various genotypes. General Linear Model statistical analysis found a significant difference in lesion volume between wild-type and PPAR-null mice for both alpha and beta isotypes. These data validate high-resolution MRI for monitoring cerebral ischemic lesions, and confirm the neuroprotective role of PPARalpha and PPARbeta in the brain.

PPARgamma in placental angiogenesis.

Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor involved in diverse biological processes including adipocyte differentiation, glucose homeostasis, and inflammatory responses. Analyses of PPARγ knockout animals have been so far preempted by the early embryonic death of PPARγ-/- embryos as a consequence of the severe alteration of their placental vasculature. Using Sox2Cre/PPARγL2/L2 mice, we obtained fully viable PPARγ-null mice through specific and total epiblastic gene deletion, thereby demonstrating that the placental defect is the unique cause of PPARγ-/- embryonic lethality. The vasculature defects observed in PPARγ-/- placentas at embryonic d 9.5 correlated with an unsettled balance of pro- and antiangiogenic factors as demonstrated by increased levels of proliferin (Prl2c2, PLF) and decreased levels of proliferin-related protein (Prl7d1, PRP), respectively. To analyze the role of PPARγ in the later stage of placental development, when its expression peaks, we treated pregnant wild-type mice with the PPARγ agonist rosiglitazone. This treatment resulted in a disorganization of the placental layers and an altered placental microvasculature, accompanied by the decreased expression of proangiogenic genes such as Prl2c2, vascular endothelial growth factor, and Pecam1. Together our data demonstrate that PPARγ plays a pivotal role in controlling placental vascular proliferation and contributes to its termination in late pregnancy.