Search results for "neuron"
showing 10 items of 2611 documents
ANALISI DELLA PERMEABILITÀ DI UNO STRATO DI CELLULE ENDOTELIALI DEI CAPILLARI CEREBRALI, CO-COLTIVATE CON NEURONI ED ASTROCITI.
2004
Estudi de la plasticitat estructural en malalties psiquiàtriques amb models animals
2021
El concepte científic de l’estrès s’associa a una resposta adaptativa front a un estímul ambiental o una demanda. Tot i això, si les pertorbacions al medi ambient són constants, es produeix un desgast a l’organisme que té efectes perjudicials en aquest. El cervell es pot considerar l’òrgan central de l’estrès, ja que en ell comença la principal resposta biològica. És conegut que esdeveniments estressants de curta duració poden potenciar les funcions neuronals i millorar el rendiment cognitiu. D’altra banda, llargs períodes d’estrès poden alterar més profundament la fisiologia de diverses regions del sistema nerviós i afectar al seu funcionament, produint dèficits cognitius i d’aprenentatge.…
Photo-inhibition of Ab fibrillation mediated by a newly designed fluorinated oxadiazole
2015
Uncontrolled aggregation of amyloid beta peptide (A?) is the main cause of Alzheimer's Disease. Therapeutic approaches of intervention in amyloid diseases include the use of small molecules able to stabilize the soluble A? conformation, or to redirect the amyloidogenic pathway towards non-toxic and non-fibrillar states. Fluorometric measurements revealed that the 3-(4'-trifluoromethylphenyl)-5-(4'-methoxyphenyl)-1,2,4-oxadiazole, when irradiated, is able to interact with monomeric A? peptide readdressing the aggregation pathway toward the formation of amorphous aggregates as evidenced by means of CD, AFM, and SAXS measurements. We hypothesize that this compound, under radiation, forms a rea…
Neuronal Nitric Oxide Synthase
2007
Neuronal nitric oxides synthase (nNOS; also referred to as NOS1 or NOS I) is a low-output enzyme that is primarily expressed in neurons. Like eNOS, it is a low-output NOS whose activity is regulated by Ca++ and calmodulin, and that produces NO in a pulsatile fashion. nNOS has a widespread distribution in the central and peripheral nervous systems. In addition, nNOS mRNA transcripts and/or protein have also been detected in non-neuronal cell types, such as rhabdomyocytes, epithelial cells, mast cells, and neutrophils …
The Significance of Low O2-Tensi0ns in the Brain Cortex for Occurrence of Metabolic Alterations under Critical Flow Conditions
1985
A reduction in the 02 supply to the brain cortex leads to O2 deficiency and curtailment of neuronal metabolism and function as soon as a minimal cellular O2 tension of 0.1 – 1 mmHG (13 – 133 Pa) can no longer be maintained (Chance et al., 1964; Grote 1967). The hypoxia-induced metabolic alterations are characterized by decreased tissue levels of the energy-rich phosphate compounds PCr and ATP. In addition, elevated concentrations of lactate, pyruvate and NADH and an increase in the lactate/pyruvate ratio and in the NADH/NAD+ ratio are to be expected (Duffy et al., 1972; Granholm and Siesjo 1969; Granholm et al., 1969; Granholm and Siesjo 1971; Grote 1978; Grote and Schubert 1982; Norberg an…
Differential antiepileptic effects of the organic calcium antagonists verapamil and flunarizine in neurons of organotypic neocortical explants from n…
1988
Effects of the organic calcium antagonists verapamil and flunarizine on pentylenetetrazol induced paroxysmal depolarizations were tested in organotypic neocortical explants taken from neonatal rats. In these in vitro experiments the papaverin derivative verapamil depressed, and finally abolished, epileptic discharges in all cases. The piperazine derivative flunarizine, however, which is known to suppress epileptic discharges in hippocampal CA3 neurons (Bingmann and Speckmann 1986), showed no significant antiepileptic effects in the explanted neocortical neurons. Thus, the present findings may indicate that the suppressive action of flunarizine on the generation of paroxysmal depolarizations…
Perception des molécules chimiosensorielles en mélange : impact du métabolisme périphérique
2015
The chemosensory system is highly sensitive and discriminant. To ensure these properties, rapid and effective mechanisms are necessary to eliminate chemosensory molecules reaching the perception interface. The xenobiotic metabolizing enzymes (XMEs) present in the peri-receptor space may participate to the clearance of molecules thus limiting chemosensory receptors saturation and promoting the termination of the signal. In our PhD thesis, the involvement of these enzymes in the detection of stimuli in mixture was assessed in two animal models allowing to test complementary aspects. In Drosophila melanogaster, a sensory exposure to caffeine causes a reversible alteration of the taste percepti…
Les enfants difficiles à table : conceptualisation et évolution
2022
L'objectif du présent article est de proposer un état des lieux des études récentes permettant d'offrir un cadre conceptuel et opérationnel au concept de comportement difficile à table, tout en mettant en lumière les conséquences psychologiques pour l'enfant, ainsi que les pratiques éducatives parentales associées. L'article ambitionne aussi de déterminer dans quelle mesure un enfant difficile est un mangeur à risque de développer ultérieurement des troubles du comportement alimentaire (anorexie mentale, ARFID), et quelles seraient les pistes à privilégier, en termes de guidance parentale, pour accompagner l'enfant.
The hedgehog receptor patched is involved in cholesterol transport.
2011
International audience; BACKGROUND: Sonic hedgehog (Shh) signaling plays a crucial role in growth and patterning during embryonic development, and also in stem cell maintenance and tissue regeneration in adults. Aberrant Shh pathway activation is involved in the development of many tumors, and one of the most affected Shh signaling steps found in these tumors is the regulation of the signaling receptor Smoothened by the Shh receptor Patched. In the present work, we investigated Patched activity and the mechanism by which Patched inhibits Smoothened. METHODOLOGY/PRINCIPAL FINDINGS: Using the well-known Shh-responding cell line of mouse fibroblasts NIH 3T3, we first observed that enhancement …
Estudio de la conectividad de los circuitos neuronales del bulbo olfatorio de los primates. Comparación de individuos control con casos de Parkinson
2015
La enfermedad de Parkinson es una enfermedad neurodegenerativa multisistémica que afecta al sistema nervioso central y periférico. Caracterizada por la degeneración selectiva de la neuronas dopaminérgicas de la sustancia negra pars compacta (SNpc), se englobada dentro de las llamadas α-sinucleinopatías. El sello distintivo de esta patología es la propagación de agregados proteicos patológicos de α-sinucleína, en forma de cuerpos y neuritas de Lewy, a lo largo de todo el sistema nervioso. La sintomatología con la que cursa esta enfermedad puede clasificarse en dos grandes categorías: síntomas no motores o pre-clínicos y síntomas motores o clínicos. Cronológicamente, los primeros anteceden a …