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31.
Abstract Data on the metabolic responses to repeated endurance exercise sessions are limited. Thus, the aims of this study were to examine (1) the impact of prior exercise on metabolic responses to a subsequent exercise session and (2) the effect of different recovery periods between two daily exercise sessions on metabolic responses to the second bout of exercise. Nine male elite athletes participated in four 25-h trials: one bout of exercise (ONE), two bouts of exercise separated by 3 h of rest and one meal (SHORT), two bouts of exercise separated by 6 h of rest and two meals (LONG), and a trial with no exercise (REST). All exercise bouts consisted of 10 min cycling at 50% followed by 65 min at 75% of maximal O2 uptake. Compared to no prior exercise (ONE), a previous bout of exercise (SHORT) was followed by higher mean O2 uptake, heart rate (HR), rectal temperature (TR), excess post-exercise oxygen consumption and lower respiratory exchange ratio (R) during and after a similar exercise session 3 h later. A longer rest interval between the two exercise bouts (6 h versus 3 h) and an additional meal resulted in a decrease in O2 uptake, HR, TR and an increase in R during the second bout of exercise, but no effects on post-exercise metabolism were found. Thus, augmented metabolic stress was observed when strenuous exercise was repeated after only 3 h of recovery, but this was attenuated when a longer recovery period including an additional meal was provided between the exercise sessions. 相似文献
32.
Stein TP; Oram-Smith JC; Leskiw MJ; Wallace HW; Long LC; Leonard JM 《The American journal of physiology》1976,230(5):1321-1325
33.
Fever and antipyresis in the lizard Dipsosaurus dorsalis 总被引:2,自引:0,他引:2
34.
Murabutide is a safe synthetic immunomodulator derived from muramyl dipeptide, the smallest bioactive unit of bacterial peptidoglycan. Although it is well known that muramyl peptides modulate the functions of monocytes/macrophages, their activity on dendritic cells is poorly documented. We thus investigated the effects of Murabutide on immunophenotype, endocytosis, T-cell stimulatory capacity, and cytokine secretion of human monocyte-derived immature dendritic cells (iDCs). We found that Murabutide triggers immunophenotypic changes as upon treatment, iDCs up-regulate the surface expression of the major histocompatibility complex type II molecule human leucocyte antigen-DR, the co-stimulatory molecules CD80, CD86 and CD40 and the differentiation marker CD83, and down-regulate the expression of the mannose receptor. These phenotypic changes are also mirrored by changes in their biological activity. Subsequent to treatment with the synthetic immunomodulator, DC have a decreased endocytic capacity but exhibit enhanced stimulatory capacity for both allogeneic and autologous T cells. In addition, Murabutide-stimulated iDCs have a greater cytostatic activity toward the tumour cell line THP-1. Furthermore, in the presence of Murabutide, DCs transiently increased the release of macrophage inhibitory protein-1 beta, tumour necrosis factor-alpha and interleukin-10, whereas the enhanced production of macrophage-colony stimulating factor was sustained over the 3-day period analysed. In addition, Murabutide triggers the phosphorylation of the three classes of mitogen-activated protein kinases in iDCs. Altogether our results demonstrate that Murabutide triggers the maturation and activation of monocyte-derived iDCs. As this immunomodulator is approved for administration in humans, it could be a useful adjunct to boost the efficacy of DC-based vaccines designed against tumours or virus-infected cells. 相似文献
35.
A D Guerci G Gerstenblith J A Brinker N C Chandra S O Gottlieb R D Bahr J L Weiss E P Shapiro J T Flaherty D E Bush 《The New England journal of medicine》1987,317(26):1613-1618
Patients presenting within four hours of the onset of acute myocardial infarction were randomly assigned to receive 80 to 100 mg of recombinant human-tissue plasminogen activator (t-PA) intravenously over a period of three hours (n = 72) or placebo (n = 66). Administration of the study drug was followed by coronary arteriography, and candidates for percutaneous transluminal coronary angioplasty were randomly assigned either to undergo angioplasty on the third hospital day (n = 42) or not to undergo angioplasty during the 10-day study period (n = 43). The patency rates of the infarct-related arteries were 66 percent in the t-PA group and 24 percent in the placebo group. No fatal or intracerebral hemorrhages occurred, and episodes of bleeding requiring transfusion were observed in 7.6 percent of the placebo group and 9.8 percent of the t-PA group. As compared with the use of placebo, administration of t-PA was associated with a higher mean (+/- SEM) ejection fraction on the 10th hospital day (53.2 +/- 2.0 vs. 46.4 +/- 2.0 percent, P less than 0.02), an improved ejection fraction during the study period (+3.6 +/- 1.3 vs. -4.7 +/- 1.3 percentage points, P less than 0.0001), and a reduction in the prevalence of congestive heart failure from 33 to 14 percent (P less than 0.01). Angioplasty improved the response of the ejection fraction to exercise (+8.1 +/- 1.4 vs. +1.2 +/- 2.2 percentage points, P less than 0.02) and reduced the incidence of postinfarction angina from 19 to 5 percent (P less than 0.05), but did not influence the ejection fraction at rest. These data support an approach to the treatment of acute myocardial infarction that includes early intravenous administration of t-PA and deferred cardiac catheterization and coronary angioplasty. 相似文献
36.
37.
38.
Vaughan JR; Farrer MJ; Wszolek ZK; Gasser T; Durr A; Agid Y; Bonifati V; DeMichele G; Volpe G; Lincoln S; Breteler M; Meco G; Brice A; Marsden CD; Hardy J; Wood NW 《Human molecular genetics》1998,7(4):751-753
A mutation in exon 4 of the human alpha-synuclein gene was reported
recently in four families with autosomal dominant Parkinson's disease (PD).
In order to examine whether mutations in this exon or elsewhere in the gene
are common in familial PD, all seven exons of the alpha- synuclein gene
were amplified by PCR from index cases of 30 European and American
Caucasian kindreds affected with autosomal dominant PD. Each product was
sequenced directly and examined for mutations in the open reading frame. No
mutations were found in any of the samples examined. We conclude that the
A53T change described in the alpha- synuclein gene is a rare cause of PD or
may even be a rare variant. Mutations in the regulatory or intronic regions
of the gene were not excluded by this study.
相似文献
39.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
40.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183