Objective: To replicate an earlier Finnish study by Keltikangas-Järvinen et al. (5) reporting that the APOE genotype is associated with temperamental traits involving increased activity.
Methods: DNA was collected from 683 Australian children who had participated in a longitudinal study of childhood temperament from 4 to 8 months up to 17 to 18 years.
The efficacy of sildenafil citrate (Viagra), an oral agent for the treatment of erectile dysfunction (ED), has been demonstrated in global studies. This 12-week randomized, double-blind, placebo-controlled, parallel-group, flexible-dose study assessed the efficacy and safety of sildenafil to treat ED in men in Egypt and South Africa. Men with ED of varied etiology were randomized to receive sildenafil 50 mg (n=128) or placebo (n=126); doses could be adjusted to 100 or 25 mg.
View Article and Find Full Text PDFUnlabelled: Capsaicin, acting at the vanilloid 1 receptor (VR1), may potentiate local anesthetic activity, and as a ligand-gated ion channel of the transient receptor potential family, may also be a target for IV general anesthetics. We have examined whether local (lidocaine, prilocaine, and procaine 0.1-10 mM; 10 mM represents 0.
View Article and Find Full Text PDFWe have recently reported that orexins (OXs) selectively evoke norepinephrine release from rat cerebrocortical slices. In the present study, we have examined orexin-opioid interactions in OXA (100 nM) and K(+) (40 mM)-evoked norepinephrine release. OXA-evoked norepinephrine release was reversed approximately 90% by SB-334867 (OX(1)-receptor antagonist) (10 microM) but not naloxone (10 microM).
View Article and Find Full Text PDFThe abilities of 19 analogues of palmitoylethanolamide and two analogues of oleoylethanolamide to affect the Ca(2+) influx into human embryonic kidney cells expressing the human vanilloid receptor (hVR1-HEK293 cells) in response to anandamide (AEA) have been investigated using a FLIPR assay and a bovine serum albumin-containing assay medium. Only palmitoylethanolamide produced any effect in the absence of AEA. The ability of palmitoylethanolamide to potentiate the response to AEA was retained when the N-CH(2)CH(2)OH group was replaced by N-CH(2)CH(2)Cl,whereas replacement with N-alkyl substituents [from -H up to -(CH(2))(12)CH(3)] resulted either in a reduction or in a complete loss of this activity.
View Article and Find Full Text PDFAdv Space Res
October 2003
Estimates of the energetic proton environment for a Mars mission are generally extrapolated from the solar proton observations at 1 AU. We find that solar particle events may be divided into two general classes. Events dominated by a near-sun injection of particles onto interplanetary magnetic field lines leading to the spacecraft position represent the "classical" solar particle event associated with solar activity.
View Article and Find Full Text PDFThe relativistic solar proton event of 6 November 1997 resulted in the first ground-level enhancement (GLE) of solar cycle 23. The earliest onset was around 1215 UT but was up to 15 minutes later at some neutron monitor locations. The time of maximum intensity also varied significantly over the world-wide neutron monitor network.
View Article and Find Full Text PDFSolar cycle 22 had significant, large fluence, energetic particle events on a scale reminiscent of the 19th solar cycle. Examination of the characteristics of these large events suggests that some of the old concepts of spectral form, intensity-time envelope and energy extrapolations, used to estimate the dose from large events that occurred during previous solar cycles should be re-evaluated. There has also been a dramatic change in perspective regarding the source of solar protons observed in interplanetary space.
View Article and Find Full Text PDF1 Capsaicin and resiniferatoxin (RTX) stimulate Ca2+ influx by activating vanilloid receptor 1 (VR1), a ligand-gated Ca2+ channel on sensory neurones. We investigated whether VR1 activation could also trigger Ca2+ mobilization from intracellular Ca2+ stores. 2 Human VR1-transfected HEK293 cells (hVR1-HEK293) were loaded with Fluo-3 or a mixture of Fluo-4 and Fura Red and imaged on a fluorometric imaging plate reader (FLIPR) and confocal microscope respectively.
View Article and Find Full Text PDFThis study compared the actions of members of five different chemical classes of vanilloid agonists at the recombinant rat vanilloid VR1 receptor expressed in HEK293 cells, and at endogenous vanilloid receptors on dorsal root ganglion cells and sensory nerves in the rat isolated mesenteric arterial bed. In mesenteric beds, vanilloids elicited dose-dependent vasorelaxation with the rank order of potency: resiniferatoxin>>capsaicin=olvanil>phorbol 12-phenyl-acetate 13-acetate 20-homovanillate (PPAHV)>isovelleral. Scutigeral was inactive.
View Article and Find Full Text PDFBackground: The aims of this study were twofold: first, to examine behavioural and academic outcomes of children with hyperactivity, using data from two longitudinal studies; and second, to examine comparable psychosocial outcomes for children with early reading difficulties.
Methods: Measures of teacher-rated persistent hyperactivity, and reading ability obtained during early primary school were available for children from the Australian Temperament Project and the Dunedin Multidisciplinary Health and Development Study. Both samples were followed up to assess behavioural and academic outcomes during the adolescent and early adult years.
Background: Anandamide, an endogenous lipid, activates both cannabinoid (CB(1)) and vanilloid (VR1) receptors, both of which are co-expressed in rat dorsal root ganglion (DRG) cells. Activation of either receptor results in analgesia but the relative contribution of CB(1) and VR1 in anandamide-induced analgesia remains controversial. Here we compare the in vitro pharmacology of recombinant and endogenous VR1 receptors using calcium imaging, in clonal and DRG cells, respectively.
View Article and Find Full Text PDFConsiderable plasticity can occur within the amino acid sequence of amphiphilic peptide hormones. This is particularly evident within the corticotropin-releasing factor (CRF) family of peptides where, despite less than 15% sequence similarity among the four paralogous lineages, all are capable of acting as high affinity ligands to members of the CRF receptor family. This suggests that these peptides could undergo many mutational changes and remain as high affinity ligands to their receptors as long as the functional motifs do not change radically.
View Article and Find Full Text PDFCapsaicin-sensitive sensory nerves are widely distributed in the cardiovascular system. They are activated by a variety of physical and chemical stimuli, characteristically by capsaicin acting via the vanilloid receptor VR1, and have a role in the regulation of peripheral vascular resistance and maintenance of homeostasis via their afferent and efferent functions. Cannabinoids, a recently discovered family of extracellular signalling molecules, can act at cannabinoid (CB) receptors expressed on sensory nerves, to cause inhibition of sensory neurotransmitter release.
View Article and Find Full Text PDFNursing Standard recently published a literature search that explored different models of integrated nursing and more traditional models of community nursing in primary care (Baileff 2000). Models of change for implementing integrated nursing were also examined. This article aims to explore the development of an integrated nursing team in a healthcare centre in Northampton.
View Article and Find Full Text PDFThere is evidence from animal experiments that the mu- and delta-opioid receptors may play a role in anxiety and depression. It might therefore be expected that functional polymorphisms of these genes in humans are associated with anxiety and depression. We investigated a single-nucleotide polymorphism (Asn40Asp) of the mu-opioid receptor gene (OPRM1).
View Article and Find Full Text PDFOrexin-A and orexin-B are two peptides derived by proteolytic cleavage from a 130 amino acid precursor prepro-orexin, which recently were isolated from the rat hypothalamus. Orexin-A is fully conserved across mammalian species, whilst rat and human orexin-B differ by 2 amino acids. These peptides bind to two G(q)-coupled receptors, termed OX(1) and OX(2).
View Article and Find Full Text PDFVanilloid receptor-1 (VR1, also known as TRPV1) is a thermosensitive, nonselective cation channel that is expressed by capsaicin-sensitive sensory afferents and is activated by noxious heat, acidic pH and the alkaloid irritant capsaicin. Although VR1 gene disruption results in a loss of capsaicin responses, it has minimal effects on thermal nociception. This and other experiments--such as those showing the existence of capsaicin-insensitive heat sensors in sensory neurons--suggest the existence of thermosensitive receptors distinct from VR1.
View Article and Find Full Text PDFWe have studied the effects of naloxone benzoylhydrazone (NalBzoH) at recombinant human OP4 receptors expressed in Chinese hamster ovary (CHO) cells (CHOhOP4) and native OP4 sites in isolated tissues from various species. In CHOhOP4 membranes, nociceptin (NC) and NalBzoH displaced [125I]Tyr14-NC with pKi values of 10.1 and 7.
View Article and Find Full Text PDF1. The abilities of a series of saturated N-acyl ethanolamines and related compounds to affect the ability of anandamide (AEA) to produce a Ca2+ influx into human embryonic kidney cells expressing the human vanilloid receptor (hVR1-HEK293 cells) has been investigated. 2.
View Article and Find Full Text PDFThe hepatic stellate cell (HSC) is now well established as the key cellular element involved in the development of hepatic fibrosis and because of this there is considerable interest in establishing the molecular events that trigger and perpetuate HSC activation. HSC activation at the level of gene transcription requires the coordinated activity of several key transcriptional regulators of the HSC genome. The considerable advances that have been made in the past five years into the mechanisms by which specific families of transcription factors regulate the profibrogenic characteristics of the activated HSC are reviewed.
View Article and Find Full Text PDFOrexin-A and -B are two peptides derived by proteolytic cleavage from a 130-amino acid precursor, prepro-orexin, which were recently isolated from the rat hypothalamus. Orexin-A is fully conserved across mammalian species, whilst rat and human orexin-B differ by two amino acids. These peptides bind to two Gq-coupled receptors, termed orexin-1 and orexin-2.
View Article and Find Full Text PDFThe vanilloid receptor-1 (VR1) is a heat-gated ion channel that is responsible for the burning sensation elicited by capsaicin. A similar sensation is reported by patients with esophagitis when they consume alcoholic beverages or are administered alcohol by injection as a medical treatment. We report here that ethanol activates primary sensory neurons, resulting in neuropeptide release or plasma extravasation in the esophagus, spinal cord or skin.
View Article and Find Full Text PDFReverse transcription polymerase chain reaction (RT-PCR) demonstrated the presence of bombesin BB2 receptor mRNA but not bombesin BB1 receptor or bombesin BB3 receptor mRNA in cultured human astrocytes. Neuromedin C hyperpolarised human astrocytes in whole-cell current and voltage clamp recordings and increased the intracellular free Ca(2+) ion concentration ([Ca(2+)](i)) in single astrocytes. Treatment with neuromedin C caused larger and more frequent increases in [Ca(2+)](i) than those triggered by neuromedin B, with 96% and 78% of cells responding, respectively.
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