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Human fetal dopamine neurons grafted in a rat model of Parkinson's disease : ultrastructural evidence for synapse formation using tyrosine hydroxylase immunocytochemistry

Human fetal mesencephalic dopamine (DA) neurons, obtained from 6.5-9 week old aborted fetuses, were grafted to the striatum of immunosuppressed rats with 6-hydroxydopamine lesions of the ascending mesostriatal DA pathway. The effects on amphetamine-induced motor asymmetry were studied at various timepoints after grafting. At eight weeks, functional graft effects were not evident but after 11 weeks

Rapid increase of BDNF mRNA levels in cortical neurons following spreading depression : regulation by glutamatergic mechanisms independent of seizure activity

Levels of mRNA for nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3) and the tyrosine kinase receptors trkB and trkC have been studied using in situ hybridization in the rat brain after topical application of KCl to the cortical surface (which induces spreading depression). Repeated episodes of spreading depression during 2 h caused a rapid and marked incre

Coexpression of neurotrophins and their receptors in neurons of the central nervous system

Nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are neuronal survival molecules which utilize the Trk family of tyrosine kinase receptors. Using double-label in situ hybridization, we demonstrate that mRNAs for BDNF and its high-affinity receptor TrkB are coexpressed in hippocampal and cortical neurons. Also, a large number of neurons in these areas coexpress NGF and BDNF mR

Turbulent heat transfer characteristics of supercritical n-decane in a vertical tube under various operating pressures

To explore the effect of the operating pressure on the flow and thermal characteristics in a vertical tube with supercritical n-decane, the inner wall temperature along the streamwise direction, the applicability of empirical correlations and buoyancy criteria are studied firstly. The mechanisms in views of density distribution, velocity field, turbulence intensity, the thickness of the thermal bo

A diabetogenic gene prevents T cells from receiving costimulatory signals

T cell fate following antigen encounter is determined by several intracellular signals generated by the interaction of the T cell with an antigen-presenting cell. In the periphery activation requires T cell receptor signaling (signal one) in combination with costimulatory signals (signal two), usually provided through the cognate interaction of CD28 and B7 molecules. Provision of signal one alone

Characterization of the potassium channels involved in EDHF-mediated relaxation in cerebral arteries

1. In the presence of N(G)-nitro-L-arginine (L-NOARG, 0.3 mM) and indomethacin (10 μM), the relaxations induced by acetylcholine and the calcium (Ca) ionophore A23187 are considered to be mediated by endothelium-derived hyperpolarizing factor (EDHF) in the guinea-pig basilar artery. 2. Inhibitors of adenosine 5'-triphosphate (ATP)-sensitive potassium (K)-channels (K(ATP); glibenclamide, 10 μM), vo

The meaning of awaiting bariatric surgery

Background:The understanding of the association between the objective conditions of health and the subjective perceptions of morbidly obese patients appears to be poor. The use of objective indicators alone produces results totally unrelated to the feelings and experiences of the bariatric patients studied. No study has approached the bariatric patient from both an inside and a preoperative perspe

Differential actions of anandamide, potassium ions and endothelium- derived hyperpolarizing factor in guinea-pig basilar artery

Vasodilator responses to anandamide (arachidonylethanolamide) and potassium ions were compared with those mediated by endothelium-derived hyperpolarizing factor (EDHF) in guinea-pig isolated basilar artery contracted with prostaglandin F(2α). In this artery, EDHF-mediated responses can be evoked by acetylcholine in the presence of both indomethacin (10 μM) and N(G)-nitro-L-arginine (0.3 mM). In en

Regional differences in endothelium‐dependent relaxation in the rat : contribution of nitric oxide and nitric oxide‐independent mechanisms

Relaxant effects of acetylcholine (ACh), histamine, calcitonin gene‐related peptide (CGRP) and the calcium ionophore A23187 were examined in rat femoral (Ø ≅ 0.2 mm), mesenteric (0.2 mm), intrarenal (0.2 mm) and hepatic (0.3 mm) arteries, and aorta (2 mm). Acetylcholine elicited an endothelium‐dependent relaxation in all arteries. Histamine induced an endothelium‐dependent relaxation in aorta, and