The European patient with Dravet syndrome: results from a parent-reported survey on antiepileptic drug use in the European population with Dravet syndrome.

Dravet syndrome is a rare form of epilepsy largely refractory to current antiepileptic medications. The only precedents of randomized placebo-controlled trials in Dravet syndrome are the two small trials that led to the approval of stiripentol. With the arrival of new clinical trials for Dravet syndrome, we sought to determine the characteristics of the patient population with Dravet syndrome in Europe today, which has possibly evolved subsequent to the approval of stiripentol and the ability to diagnose milder clinical cases via genetic testing.

New in vitro phenotypic assay for epilepsy: fluorescent measurement of synchronized neuronal calcium oscillations.

Research in the epilepsy field is moving from a primary focus on controlling seizures to addressing disease pathophysiology. This requires the adoption of resource- and time-consuming animal models of chronic epilepsy which are no longer able to sustain the testing of even moderate numbers of compounds. Therefore, new in vitro functional assays of epilepsy are needed that are able to provide a medium throughput while still preserving sufficient biological context to allow for the identification of compounds with new modes of action.

Internal regulation of neurite plasticity: A general model.

The mature central nervous system has a very limited capacity to repair itself after injury or disease, often leading to lifelong disabilities. Two key questions in neurobiology are why the brain has such limited plasticity, and how we could enhance it. There has been extensive research on how external inhibitors, present in the mature central nervous system, cooperate to restrict neurite plasticity-the ability of neurons to sprout and reorganize their connections.

Varicones and growth cones: two neurite terminals in PC12 cells.

The rat adrenal pheochromocytoma PC12 cell line is one of the traditional models for the study of neurite outgrowth and growth cone behavior. To clarify to what extent PC12 neurite terminals can be compared to neuronal growth cones, we have analyzed their morphology and protein distribution in fixed PC12 cells by immunocytochemistry. Our results show that that PC12 cells display a special kind of neurite terminal that includes a varicosity in close association with a growth cone.

Neurite consolidation is an active process requiring constant repression of protrusive activity.

During development, neurons extend projections that pathfind to reach their appropriate targets. These projections are composed of two distinct domains: a highly dynamic growth cone and a stable neurite shaft, which is considered to be consolidated. Although the regulation of these domains is critical to the appropriate formation of neural networks, the molecular mechanisms that regulate neurite shape remain poorly understood.

Cerebellar GABAergic progenitors adopt an external granule cell-like phenotype in the absence of Ptf1a transcription factor expression.

We report in this study that, in the cerebellum, the pancreatic transcription factor Ptf1a is required for the specific generation of Purkinje cells (PCs) and interneurons. Moreover, granule cell progenitors in the external GCL (EGL) appear to be unaffected by deletion of Ptf1a. Cell lineage analysis in Ptf1a(Cre/Cre) mice was used to establish that, in the absence of Ptf1a expression, ventricular zone progenitors, normally fated to produce PCs and interneurons, aberrantly migrate to the EGL and express typical markers of these cells, such as Math1, Reelin, and Zic1/2.

Involvement of the myelin-associated inhibitor Nogo-A in early cortical development and neuronal maturation.

Nogo-A is a myelin-associated protein expressed by neurons and myelinating mature oligodendrocytes in the central nervous system. Although most research has focused on the participation of Nogo-A in the prevention of axonal regeneration and plasticity in the adult, little attention has been paid to the putative functions of Nogo-A during embryonic development. Here we examined the general pattern and cell-specific distribution of Nogo-A in the prenatal mouse telencephalon.