Search results for "neuron"
showing 10 items of 2611 documents
Unexpected substitution of dominant rotavirus G genotypes in French hospitalized children over five consecutive seasons.
2009
International audience; The study was designed to evaluate the circulation of group A rotaviruses in French hospitalized children, and to detect unusual strains. This prospective study was conducted from 2001 to 2006 in children consulting for acute diarrhea at the pediatric emergency department in three French University Hospitals. The rotaviruses were detected by rapid test and genotyped by RT-PCR on the basis of their outer capsid proteins VP4 (P-type) and VP7 (G-type). The stools from 757 children were analyzed. G1P[8] strains were predominant (44.0%), followed by G9P[8] (17.7%), G3P[8] 13.1%, G4P[8] (9.5%), and G2P[4] (1.8%); mixed rotavirus infections occurred in 2.3%. G9 rotaviruses …
The effect of neurodegenerative lesions on the mechanism of motor resonance induced by action observation
2018
The concept of “embodied cognition” considers that the classical Perception-Cognition-Action architecture proposing a sequential flow of processing with clean cuts between all modules is not appropriate to understand the behavioral effect of neurodegenerative disorders and to find innovative therapeutic solutions. In the last decades, the discovery of the mirror neurons (MN) has given a biological substrate to this theoretical perspective: the MN are now thought linking together knowledge about actions and perceptions not only to integrate perception in action planning and execution but also as a neural mechanism supporting a wide range of cognitive functions, e.g. empathy and language. At …
Red wine extract prevents neuronal apoptosis in vitro and reduces mortality of transgenic mice.
2007
In this work, we have investigated the effects of nutritional antioxidants as antidegenerative agents on glutamate-induced apoptosis in primary cultures of cerebellar granule neurons (CGNs). Glutamate-induced apoptosis is also associated with intracellular [Ca(2+)]i overload, generation of reactive oxygen species (ROS), depression of cell energy metabolism, cytochrome c release, and increase in caspase-3 activity. Pretreatment (3 h) with red wine extract (5 microg/mL) and ascorbic acid (30 microM) blocks glutamate-induced apoptosis in CGNs. In vivo experiments carried out on transgenic mice expressing the human mutated Cu, Zn superoxide dismutase (SOD1) G93A (mSOD1(G93A)) show that mice fed…
Rot1 plays an antagonistic role to Clb2 in actin cytoskeleton dynamics throughout the cell cycle.
2007
ROT1 is an essential gene whose inactivation causes defects in cell cycle progression and morphogenesis in budding yeast. Rot1 affects the actin cytoskeleton during the cell cycle at two levels. First, it is required for the maintenance of apical growth during bud growth. Second, Rot1 is necessary to polarize actin cytoskeleton to the neck region at the end of mitosis; because of this defect, rot1 cells do not properly form a septum to complete cell division. The inability to polarize the actin cytoskeleton at the end of mitosis is not due to a defect in the recruitment of the polarisome scaffold protein Spa2 or the actin cytoskeleton regulators Cdc42 and Cdc24 in the neck region. Previous …
Direct interaction of the Usher syndrome 1G protein SANS and myomegalin in the retina
2011
Contains fulltext : 96822.pdf (Publisher’s version ) (Closed access) The human Usher syndrome (USH) is the most frequent cause of combined hereditary deaf-blindness. USH is genetically heterogeneous with at least 11 chromosomal loci assigned to 3 clinical types, USH1-3. We have previously demonstrated that all USH1 and 2 proteins in the eye and the inner ear are organized into protein networks by scaffold proteins. This has contributed essentially to our current understanding of the function of USH proteins and explains why defects in proteins of different families cause very similar phenotypes. We have previously shown that the USH1G protein SANS (scaffold protein containing ankyrin repeat…
Channeled scaffolds implanted in adult rat brain.
2012
Scaffolds with aligned channels based on acrylate copolymers, which had previously demonstrated good com- patibility with neural progenitor cells were studied as coloniz- able structures both in vitro with neural progenitor cells and in vivo, implanted without cells in two different locations, in the cortical plate of adult rat brains and close to the subven- tricular zone. In vitro, neuroprogenitors colonize the scaffold and differentiate into neurons and glia within its channels. When implanted in vivo immunohistochemical analysis by confocal microscopy for neural and endothelial cells markers demonstrated that the scaffolds maintained continuity with the surrounding neural tissue and wer…
Polybutylene succinate artificial scaffold for peripheral nerve regeneration
2021
Regeneration and recovery of nerve tissues are a great challenge for medicine, and positively affect the quality of life of patients. The development of tissue engineering offers a new approach to the problem with the creation of multifunctional artificial scaffolds that act on various levels in the damaged tissue, providing physical and biochemical support for the growth of nerve cells. In this study, the effects of the use of a tubular scaffold made of polybutylene succinate (PBS), surgically positioned at the level of a sciatic nerve injured in rat, between the proximal stump and the distal one, was investigated. Scaffolds characterization was carried out by scanning electron microscopy …
Integration of Gravitational Torques in Cerebellar Pathways Allows for the Dynamic Inverse Computation of Vertical Pointing Movements of a Robot Arm
2008
BackgroundSeveral authors suggested that gravitational forces are centrally represented in the brain for planning, control and sensorimotor predictions of movements. Furthermore, some studies proposed that the cerebellum computes the inverse dynamics (internal inverse model) whereas others suggested that it computes sensorimotor predictions (internal forward model).Methodology/principal findingsThis study proposes a model of cerebellar pathways deduced from both biological and physical constraints. The model learns the dynamic inverse computation of the effect of gravitational torques from its sensorimotor predictions without calculating an explicit inverse computation. By using supervised …
When the brain goes diving: glial oxidative metabolism may confer hypoxia tolerance to the seal brain.
2009
Deep diving mammals have developed strategies to cope with limited oxygen availability when submerged. These adaptations are associated with an increased neuronal hypoxia tolerance. Brain neurons of the hooded seal Cysto- phora cristata remain much longer active in hypoxic condi- tions than those of mice. To understand the cellular basis of neuronal hypoxia tolerance, we studied neuroglobin and cy- tochrome c in C. cristata brain. Neuroglobin, a respiratory protein typically found in vertebrate neurons, displays three unique amino acid substitutions in hooded seal. However, these substitutions unlikely contribute to a modulation of O2 affinity. Moreover, there is no significant difference i…
Collective Intentionality, Methodological Solipsism, and Current Neurosciences.
2008
L’intervento analizza la teoria searleana dell’intenzionalità collettiva e la sua pretesa di superamento della dicotomia tra approcci individualisti (riduzionisti) e collettivisti all’intenzionalità collettiva considerandone la plausibilità alla luce della recente scoperta dei mirror neurons (interpretata alla luce delle teorie di Gallese e Rizzolatti) e della più generale concezione della mente come sistema autonomo modulato dall’ambiente quale emerge dalle teorie di Edelman e Llinàs.