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41.
Angela J. Drake-Holland Mark I. M. Noble Sara Pugh Christopher Mills 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1988,2(2):239-243
Summary In this study any changes in action potential duration or Q-T interval due to acute doses of ketanserin were monitored. The effect of a bolus dose (10 or 20 mg) followed by an infusion (10 or 20 mg over 20 minutes) of ketanserin on the Q-T interval and action potential duration was studied in six patients undergoing routine cardiac catheterization. Action potential duration was measured with a silver-silver chloride electrode catheter while heart rate was kept constant by atrial pacing and reflex effects avoided by -adrenergic blockade. There were some prolongations of the action potential duration but they were not in excess of 40 msec and did not reach statistical significance (control 263±46.0 msec; bolus 269±52.1 msec; infusion 262±53.6 msec; nor were there any significant changes in Q-T interval. Thus acute intravenous doses of ketanserin, in the absence of hypokalaemia or other Q-T interval-prolonging drugs, have no consistent effect on Q-T interval or action potential duration; prolongation of the action potential, when it occurs, is small. 相似文献
42.
Gao HZ Kobayashi K Tabata A Tsuge H Iijima M Yasuda T Kalkanoglu HS Dursun A Tokatli A Coskun T Trefz FK Skladal D Mandel H Seidel J Kodama S Shirane S Ichida T Makino S Yoshino M Kang JH Mizuguchi M Barshop BA Fuchinoue S Seneca S Zeesman S Knerr I Rodés M Wasant P Yoshida I De Meirleir L Abdul Jalil M Begum L Horiuchi M Katunuma N Nakagawa S Saheki T 《Human mutation》2003,22(1):24-34
Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease. 相似文献
43.
Paramyxoviruses of type 1 (PMV-l) isolated from pigeons were genetically analyzed. A part of the fusion and the matrix protein genes were amplified and sequenced, Typical amino acid sequences associated with virulence were determined at the fusion protein cleavage site in all PMV-1 isolates. All Slovene pigeon PMV-1 strains share high amino acid sequence similarity with other pigeon strains. In the phylogenetic tree, they are clustered together with pigeon PMV-1 isolates with moderate pathogenicity. Phylogenetic analysis obtained from the fusion and the matrix protein gene alignments showed the same branching order. Viruses circulating among pigeons were found to form quite unique lineage of virulent NDV strains. 相似文献
44.
45.
Effects of a brisk walk on lipoprotein lipase activity and plasma triglyceride concentrations in the fasted and postprandial states 总被引:3,自引:0,他引:3
This study aimed to determine whether changes in plasma heparin-releasable lipoprotein lipase (LPL) activity following a brisk
walk were associated with decreases in fasting and/or postprandial triglyceride (TG) concentrations. Two groups of pre-menopausal
women participated. In one group (fasting study group, n=10), TG concentrations and post-heparin plasma LPL activity were measured in the fasted state on two occasions: ~18 h after
a 2-h treadmill walk at 50% maximal oxygen uptake (exercise trial); and after a day of no exercise (control trial). The other
group (postprandial study group, n=9) undertook two oral fat tolerance tests (blood samples taken fasting and for 6 h after a high-fat meal), with plasma LPL
activity measured 6 h after meal ingestion. Pre-conditions were the same as for the fasting study group (i.e. control and
prior exercise). Prior exercise reduced fasting TG concentrations by 23 (7)% (fasting study group) [mean (SEM)] and by 18
(9)% (postprandial study group) (both P<0.05), and the postprandial TG response by 23 (6)% (postprandial study group) (P<0.01). Plasma LPL activity was not significantly increased by exercise in either the fasting or postprandial study groups.
However, exercise-induced changes in both fasting and postprandial LPL activity were significantly correlated with the respective
exercise-induced changes in fasting TG concentration and the postprandial TG response (r=−0.70 and −0.77 respectively, P<0.05 for both). These data suggest that increased LPL activity may contribute to the hypotriglyceridaemic effect of moderate
exercise, although other mechanisms are also likely to be involved.
Electronic Publication 相似文献
46.
Lymphopenia is due to a frameshift mutation in Gimap5 on rat chromosome 4 and is linked to type 1 diabetes in the diabetes prone (DP) BB rat. The hypothesis that bone marrow derived cells confer the lymphopenia phenotype was tested by reciprocal bone marrow transplantation in 40-day-old lethally irradiated diabetes resistant (DR) congenic DR.lyp/lyp (lymphopenia and diabetes) and DR.+/+ (no lymphopenia and no diabetes) rats. In two independent series of transplants, all DR.lyp/lyp rats (n=5 and 4) receiving DR.lyp/lyp bone marrow retained lymphopenia and developed insulitis (5/5 and 4/4) as well as diabetes in some (2/5 and 3/4). Both DR.+/+ and DR.lyp/lyp rats receiving DR.+/+ bone marrow cells as well as DR.+/+ rats receiving DR.lyp/lyp bone marrow cells showed no lymphopenia or diabetes. In accordance with earlier studies in non-congenic BB rats, the DR.+/+ rats receiving DR.lyp/lyp bone marrow cells recapitulated an intermediary phenotype rather than the +/+ or lyp/lyp phenotypes. Our data demonstrate that BBDP rat lymphopenia and diabetes are transferred by bone marrow transplantation to syngeneic DR.lyp/lyp but not DR.+/+ recipients. The intermediary recapitulation of DR.lyp/lyp T cells in recipient DR.+/-/+/- rats suggests that radiation resistant +/-/+/- T cells, the Gimap5 mutation in bone marrow cells, or both may not support the development of lymphopenia. 相似文献
47.
The Role of APO-1-Mediated Apoptosis in the Immune System 总被引:12,自引:0,他引:12
48.
Aspects of social and emotional competence in adult attention-deficit/hyperactivity disorder 总被引:4,自引:0,他引:4
Friedman SR Rapport LJ Lumley M Tzelepis A VanVoorhis A Stettner L Kakaati L 《Neuropsychology》2003,17(1):50-58
Social and emotional competence were evaluated using self-report and behavioral measures in adults with attention-deficit/hyperactivity disorder (ADHD) and controls. Adults with ADHD viewed themselves as less socially competent but more sensitive toward violations of social norms than controls. Films depicting emotional interactions were used to assess linguistic properties of free recall and perceived emotional intensity. Although adults with ADHD used more words to describe the scenes, they used fewer emotion-related words, despite rating the emotions depicted as more intense than did controls. In contrast, no group differences for words depicting social or cognitive processes were observed. Overall, adults with ADHD appear more aware of their problems in social versus emotional skills. Findings may have implications for improving the psychosocial functioning of these adults. 相似文献
49.
Background
Physicians' awareness of their important role in defusing the obesity epidemic has increased. However, the number of family practitioners who treat obesity problems continues to be low. Self-efficacy refers to the belief in one's ability to organize and execute the courses of action required to produce given attainments. Thus, practitioners who judge themselves incapable of managing obesity do not even try. We hypothesized that practitioners' self-efficacy and motivation would be enhanced as a result of participating in an interactive course designed to enrich their knowledge of obesity management. 相似文献50.
Mast cell tryptase and proteinase-activated receptor 2 induce hyperexcitability of guinea-pig submucosal neurons 总被引:5,自引:2,他引:5
David E. Reed Carlos Barajas-Lopez Graeme Cottrell Sara Velazquez-Rocha Olivier Dery Eileen F. Grady Nigel W. Bunnett Stephen J. Vanner 《The Journal of physiology》2003,547(2):531-542
Mast cells that are in close proximity to autonomic and enteric nerves release several mediators that cause neuronal hyperexcitability. This study examined whether mast cell tryptase evokes acute and long-term hyperexcitability in submucosal neurons from the guinea-pig ileum by activating proteinase-activated receptor 2 (PAR2) on these neurons. We detected the expression of PAR2 in the submucosal plexus using RT-PCR. Most submucosal neurons displayed PAR2 immunoreactivity, including those colocalizing VIP. Brief (minutes) application of selective PAR2 agonists, including trypsin, the activating peptide SL-NH2 and mast cell tryptase, evoked depolarizations of the submucosal neurons, as measured with intracellular recording techniques. The membrane potential returned to resting values following washout of agonists, but most neurons were hyperexcitable for the duration of recordings (> 30 min–hours) and exhibited an increased input resistance and amplitude of fast EPSPs. Trypsin, in the presence of soybean trypsin inhibitor, and the reverse sequence of the activating peptide (LR-NH2 ) had no effect on neuronal membrane potential or long-term excitability. Degranulation of mast cells in the presence of antagonists of established excitatory mast cell mediators (histamine, 5-HT, prostaglandins) also caused depolarization, and following washout of antigen, long-term excitation was observed. Mast cell degranulation resulted in the release of proteases, which desensitized neurons to other agonists of PAR2. Our results suggest that proteases from degranulated mast cells cleave PAR2 on submucosal neurons to cause acute and long-term hyperexcitability. This signalling pathway between immune cells and neurons is a previously unrecognized mechanism that could contribute to chronic alterations in visceral function. 相似文献