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191.
Gil Rodas Mar Calvo Asunción Estruch Eduardo Garrido Guadalupe Ercilla Antoni Arcas Ramon Segura Josep L. Ventura 《European journal of applied physiology and occupational physiology》1998,77(6):511-516
Running economy (RE), defined as the steady-state of oxygen uptake (V˙O2) for a given running velocity, is a factor of sports performance the genetic component of which has seldom been reported
to date. We studied this component using a heritability index (HI) in a group of 32 male twins, 8 monozygotic (MZ) and 8 dizygotic
(DZ) pairs, all sportsmen with similar perinatal and environmental backgrounds. Zygocity was determined by the identity of
erythrocytic antigenic, protein and enzymatic polymorphism, and human leucocyte antigen serologic types between co-twins.
The subjects exercised twice on a treadmill, once until exhaustion and again at submaximal intensities. Pulmonary gas exchange
was measured continuously using an automatic analyser system during both tests. Blood samples were obtained during the recovery
period to determine lactate concentrations. No significant differences were observed between MZ and DZ, in respect of RE at
any speed or in maximal V˙O2 relative to body mass. Nevertheless, significant HI (P < 0.05) was found in maximal lactate concentrations (HI = 0.75) and in respiratory equivalent for oxygen at two speeds, 7 km · h−1 (HI = 0.71) and 8 km · h−1 (HI = 0.79), differences which probably suggest that there are differences in RE. In conclusion, we did not detect a genetic
component in RE or in maximal oxygen uptake, but a genetic component for markers of anaerobic metabolism was present.
Accepted: 5 November 1997 相似文献
192.
193.
Carlos de la Haba Antoni Morros Paz Martínez José R. Palacio 《The Journal of membrane biology》2016,249(6):789-800
Macrophage activation is essential for a correct and efficient response of innate immunity. During oxidative stress membrane receptors and/or membrane lipid dynamics can be altered, leading to dysfunctional cell responses. Our aim is to analyze membrane fluidity modifications and cell function under oxidative stress in LPS-activated macrophages. Membrane fluidity of individual living THP-1 macrophages was evaluated by the technique two-photon microscopy. LPS-activated macrophage function was determined by TNFα secretion. It was shown that LPS activation causes fluidification of macrophage plasma membrane and production of TNFα. However, oxidative stress induces rigidification of macrophage plasma membrane and inhibition of cell activation, which is evidenced by a decrease of TNFα secretion. Thus, under oxidative conditions macrophage proinflammatory response might develop in an inefficient manner. 相似文献
194.
Membrane fluidity changes in goat sperm induced by cholesterol depletion using beta-cyclodextrin 总被引:1,自引:0,他引:1
Companyó M Iborra A Villaverde J Martínez P Morros A 《Biochimica et biophysica acta》2007,1768(9):2246-2255
Cholesterol efflux from membranes promotes acrosome reaction in goat spermatozoa. In 1 h of incubation of sperm in the presence of beta-cyclodextrin (beta CD), all the interchangeable cholesterol is desorbed from sperm membranes, although acrosome reaction is fully accomplished only after 3-4 h of incubation, as previously published. In the present paper we investigate the effect of cholesterol removal from mature goat spermatozoa on the overall membrane "fluidity" of live cell membranes and of liposomes from sperm lipid extracts. Using steady state fluorescence anisotropy of 1,6-diphenyl-1,3,5-hexatriene (DPH), we studied the average thermotropic behaviour of membrane lipids, after incubation of live sperm for 1 h in BSA-free medium with the presence/absence of 8 mM beta-cyclodextrin, as a cholesterol acceptor. Unimodal and bimodal theoretical sigmoids fitted best to the experimental thermotropic profiles of liposomes and whole cells, respectively. In the case of whole sperm, two phase transitions, attributable to different lipid domains, were clearly separated by using the fitting parameters. After cholesterol removal, important changes in the relative anisotropy range of the two transitions were found, indicating an increase in the "fluidity" of some of the lipid microdomains of sperm membranes. These changes in sperm lipid dynamics are produced before the onset of sperm acrosome reaction. 相似文献
195.
Puig S Mira H Dorcey E Sancenón V Andrés-Colás N Garcia-Molina A Burkhead JL Gogolin KA Abdel-Ghany SE Thiele DJ Ecker JR Pilon M Peñarrubia L 《Biochemical and biophysical research communications》2007,354(2):385-390
Copper (Cu) chaperones constitute a family of small Cu+-binding proteins required for Cu homeostasis in eukaryotes. The ATX1 family of Cu chaperones specifically delivers Cu to heavy metal P-type ATPases. The plant Arabidopsis thaliana expresses the ATX1-like Cu chaperone CCH, which exhibits a plant-specific carboxy-terminal domain (CTD) with unique structural properties. We show that CCH homologues from other higher plants contain CTDs with structural properties similar to Arabidopsis CCH. Furthermore, we identify a new ATX1-like Cu chaperone in Arabidopsis, AtATX1, which functionally complements yeast atx1Delta and sod1Delta associated phenotypes, and localizes to the cytosol of Arabidopsis cells. Interestingly, AtATX1, but not full-length CCH, interacts in vivo with the Arabidopsis RAN1 Cu-transporting P-type ATPase by yeast two-hybrid. We propose that higher plants express two types of ATX1-like Cu chaperones: the ATX1-type with a predominant function in Cu delivery to P-type ATPases, and the CCH-type with additional CTD-mediated plant-specific functions. 相似文献
196.
197.
Martin Schmitt Jordan Eber Delphine Antoni Georges Noel 《Reports of Practical Oncology and Radiotherapy》2021,26(5):814
BackgroundBreast cancer is the most frequent cancer in women in France. Its management has evolved considerably in recent years with a focus on reducing iatrogenic toxicity. The radiotherapy indications are validated in multidisciplinary consultation meetings; however, questions remain outstanding, particularly regarding hypofractionated radiotherapy, partial breast irradiation, and irradiation of the internal mammary chain and axillary lymph node area.Materials and methodsAn online survey was sent to 47 heads of radiotherapy departments in France. The survey consisted of 22 questions concerning indications for irradiation of the supraclavicular, internal mammary and axillary lymph node areas; irradiation techniques and modalities; prescribed doses; and fractionation.ResultsTwenty-four out of 47 centers responded (response rate of 51%). This survey demonstrated a wide variation in the prescribed dose regimen, monoisocentric radiotherapy, and indications of irradiation of the lymph node areas.ConclusionThis survey provides insight into the current radiotherapy practice for breast cancer in France. It shows the need to standardize practices. 相似文献
198.
The present study provides quantitative and qualitative analyses of the dentition of Discopyge tschudii. Overall, 193 individuals (99 males and 94 females) of D. tschudii were collected on scientific trawl surveys conducted by the National Institute for Fisheries Research and Development (INIDEP) and commercial vessels in Argentina. Discopyge tschudii has rhombic‐shaped teeth, arranged in a semipavement‐like dentition; each tooth has an erect cusp slightly inclined posteriorly and holaulachorized root. Mature males have greater tooth lengths than females and immature specimens. Discopyge tschudii exhibits dignathic homodonty and gradient monognathic heterodonty where teeth of the commissural row are shorter than those of the symphyseal and internal rows. 相似文献
199.
Extracellular vesicles do not contribute to higher circulating levels of soluble LRP1 in idiopathic dilated cardiomyopathy
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Santiago Roura Carolina Gálvez‐Montón David de Gonzalo‐Calvo Ana Gámez Valero Paloma Gastelurrutia Elena Revuelta‐López Cristina Prat‐Vidal Carolina Soler‐Botija Aida Llucià‐Valldeperas Isaac Perea‐Gil Oriol Iborra‐Egea Francesc E. Borràs Josep Lupón Vicenta Llorente‐Cortés Antoni Bayes‐Genis 《Journal of cellular and molecular medicine》2017,21(11):3000-3009
Idiopathic dilated cardiomyopathy (IDCM) is a frequent cause of heart transplantation. Potentially valuable blood markers are being sought, and low‐density lipoprotein receptor‐related protein 1 (LRP1) has been linked to the underlying molecular basis of the disease. This study compared circulating levels of soluble LRP1 (sLRP1) in IDCM patients and healthy controls and elucidated whether sLRP1 is exported out of the myocardium through extracellular vesicles (EVs) to gain a better understanding of the pathogenesis of the disease. LRP1 α chain expression was analysed in samples collected from the left ventricles of explanted hearts using immunohistochemistry. sLRP1 concentrations were determined in platelet‐free plasma by enzyme‐linked immunosorbent assay. Plasma‐derived EVs were extracted by size‐exclusion chromatography (SEC) and characterized by nanoparticle tracking analysis and cryo‐transmission electron microscopy. The distributions of vesicular (CD9, CD81) and myocardial (caveolin‐3) proteins and LRP1 α chain were assessed in SEC fractions by flow cytometry. LRP1 α chain was preferably localized to blood vessels in IDCM compared to control myocardium. Circulating sLRP1 was increased in IDCM patients. CD9‐ and CD81‐positive fractions enriched with membrane vesicles with the expected size and morphology were isolated from both groups. The LRP1 α chain was not present in these SEC fractions, which were also positive for caveolin‐3. The increase in circulating sLRP1 in IDCM patients may be clinically valuable. Although EVs do not contribute to higher sLRP1 levels in IDCM, a comprehensive analysis of EV content would provide further insights into the search for novel blood markers. 相似文献
200.
Josep A. Tur Lluís Serra‐Majem Dora Romaguera Antoni Pons 《Obesity (Silver Spring, Md.)》2005,13(3):527-536
Objective: To assess the prevalence of excess weight (obesity and overweight) and the related environmental risk factors in a Mediterranean population. Self‐perception of body weight, attitudes toward weight‐control behaviors, and the associated factors were also examined. Research Methods and Procedures: A cross‐sectional nutritional survey was carried out in the Balearic Islands between 1999 and 2000. A random sample (n = 1200) of the adult population (20 to 60 years old) was interviewed. Dietary questionnaires and a global questionnaire incorporating questions related to sociodemographic and lifestyle variables were utilized. Anthropometric measurements were also obtained. Results: Nearly one‐half of the population of the Balearic Islands is above the normal weight range (BMI > 25). The predictors of overweight and obesity in the Balearic Islands are to be over 40 years old, to be married, to form part of the lowest educational levels, and to have a sedentary lifestyle. A large percentage of excess‐weight individuals tend to underestimate their BMI, are not concerned about their weight status, tend to snack more often, and have never dieted. Discussion: Although the likely causes of the rise in obesity prevalence are difficult to elucidate from this study, we have identified the profile of individuals with excess weight in the Balearic Islands as well as their attitudes toward their body image. 相似文献