Search results for "Volt"
showing 10 items of 2187 documents
Immunohistochemical marker for Na+ CP type Vα (C-20) and heterozygous nonsense SCN5A mutation W822X in a sudden cardiac death induced by mild anaphyl…
2009
A sudden death likely due to mild anaphylactic reaction in a young man is described. Autoptic, histologic, immunohistochemical, and laboratory findings were strongly consistent with the diagnosis of a mild anaphylactic reaction. Genetic molecular analysis, performed on formalin-fixed, paraffin-embedded tissues, showed a mutation described as W822X in a family with electrocardiographic pattern typical of Brugada Syndrome. It results in a nonsense mutation generating a truncated form of the channel protein. The mutation is due to a point substitution of a guanine with an adenine residue (G2466A). Immunohistochemistry and laser scanning confocal microscopy on sections from heart formalin-fixed…
Postnatal increases in axonal conduction velocity of an identified Drosophila interneuron require fast sodium, L-type calcium and shaker potassium ch…
2019
Abstract During early postnatal life, speed up of signal propagation through many central and peripheral neurons has been associated with an increase in axon diameter or/and myelination. Especially in unmyelinated axons postnatal adjustments of axonal membrane conductances is potentially a third mechanism but solid evidence is lacking. Here, we show that axonal action potential (AP) conduction velocity in the Drosophila giant fiber (GF) interneuron, which is required for fast long-distance signal conduction through the escape circuit, is increased by 80% during the first day of adult life. Genetic manipulations indicate that this postnatal increase in AP conduction velocity in the unmyelina…
A novel mutation in KCNQ3-related benign familial neonatal epilepsy: electroclinical features and neurodevelopmental outcome.
2019
Benign familial neonatal epilepsy (BFNE) is caused, in about 5% of families, by mutations in the KCNQ3 gene encoding voltage-gated potassium channel subunits. Usually, newborns with BFNE show a normal neurological outcome, but recently, refractory seizures and/or developmental disability have been reported suggesting phenotype variability associated with KCNQ3-related BFNE. Here, we describe a proband from a BFNE family carrying a novel variant in the KCNQ3 gene. Regarding the paucity of data in the literature, we describe the presented case with a view to further establishing: (1) a genotype/phenotype correlation in order to define a BFNE phenotype associated with favourable outcome; (2) a…
A novel KCNQ3 mutation in familial epilepsy with focal seizures and intellectual disability
2015
Mutations in the KCNQ2 gene encoding for voltage-gated potassium channel subunits have been found in patients affected with early onset epilepsies with wide phenotypic heterogeneity, ranging from benign familial neonatal seizures (BFNS) to epileptic encephalopathy with cognitive impairment, drug resistance, and characteristic electroencephalography (EEG) and neuroradiologic features. By contrast, only few KCNQ3 mutations have been rarely described, mostly in patients with typical BFNS. We report clinical, genetic, and functional data from a family in which early onset epilepsy and neurocognitive deficits segregated with a novel mutation in KCNQ3 (c.989G>T; p.R330L). Electrophysiological stu…
Changes in cytosolic calcium in response to noxious heat and their relationship to vanilloid receptors in rat dorsal root ganglion neurons.
2001
Heat transduction mechanisms in primary nociceptive afferents have been suggested to involve a vanilloid receptor channel with high calcium permeability. To characterize the changes in free cytosolic calcium evoked by noxious heat stimuli (< or =51 degrees C, 10s), we performed microfluorometric measurements in acutely dissociated small dorsal root ganglion neurons (< or =32.5 microm) of adult rats using the dye FURA-2. Only neurons that responded with a reversible increase in intracellular calcium to high potassium were evaluated. Heat-induced calcium transients (exceeding mean + 3S.D. of the temperature dependence of the dye) were found in 66 of 105 neurons. These transients increased non…
Impact of rectal distension on prostate CBCT-based positioning assessed with 6 degrees-of-freedom couch
2018
International audience; Introduction: Prostate requires a daily correction of its 3-dimensional position in relation with rectal distension. In this study, we sought to determine whether rectal distension with respect to the rectal behavior might have an impact on prostate translations and/or rotations during prostate image guided radiation therapy using a 6 degrees-of-freedom (DOF) couch.Methods and materials: We reviewed the data from 39 patients with localized prostate cancer treated with protracted external radiation therapy using a 6 DOF couch. Before each fraction, a kilovoltage cone beam computed tomography (kV-CBCT) scan was performed. The automatic fusion algorithm was set to fuse …
Inhibitory effect of caffeic acid phenethyl ester, a plant-derived polyphenolic compound, on rat intestinal contractility
2009
Abstract Caffeic acid phenethyl ester (CAPE) exerts pharmacological actions (e.g. anti-inflammatory, chemopreventive) which are relevant for potential clinical application in the digestive tract. However, no study has been published on its possible effects on intestinal motility, to date. In the present study, we investigated the effect of this plant-derived polyphenolic compound on the spontaneous contractions of the rat isolated ileum. CAPE reduced (in a tetrodotoxin-insensitive manner) spontaneous ileal contractions and this effect was reduced by the l -type Ca 2+ channel blocker nifedipine and the chelant of calcium ethylenediaminetetraacetic acid. However, the effect of CAPE was not mo…
Analysis of the membrane potential of rat- and mouse-liver mitochondria by flow cytometry and possible applications.
1990
Washed and purified rat- or mouse-liver mitochondria exhibiting high membrane integrity and metabolic activity were studied by flow cytometry. The electrophoretic accumulation/redistribution of cationic lipophilic probes, rhodamine 123, safranine O and a cyanine derivative, 3,3'-dihexyloxadicarbocyanine iodide, during the energization process was studied and was consistent with the generation of a negative internal membrane potential. An exception to this was nonylacridine orange which spontaneously bound to the mitochondrial membrane by hydrophobic interactions via its hydrocarbon chain. Energized purified mitochondria stained with potentiometric dyes exhibited both higher fluorescence and…
Alternating current voltammetric determination of DNA damage
1990
Abstract The conditions for alternating current (a.c.) voltammetric DNA determinations have been investigated with respect to its use with alkaline filter elution techniques at low DNA concentrations. In inorganic electrolyte solutions three current peaks can be distinguished: peak I around −1.1 V caused by the reorientation or desorption of DNA segments; peak II around −1.2 V caused by the native DNA (nDNA) form; peak III caused by denatured DNA (dDNA) at −1.4 V. Sonication of nDNA increases the peak current, however not with dDNA. Both dDNA and nDNA give linear peak current increments with DNA increments, their regression lines cutting the concentration axis at the origin. In filter eluti…
Ceramide inhibits Kv currents and contributes to TP-receptor-induced vasoconstriction in rat and human pulmonary arteries
2011
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