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1.
The ACTN3 R577X polymorphism (rs1815739) is a strong candidate to influence elite athletic performance. Yet, controversy exists in the literature owing to between-studies differences in the ethnic background and sample size of the cohorts, the latter being usually low, which makes comparisons difficult. In this case:control genetic study we determined the association between elite athletic status and the ACTN3 R577X polymorphism within three cohorts of European Caucasian men, i.e. Spanish, Polish and Russian [633 cases (278 elite endurance and 355 power athletes), and 808 non-athletic controls]. The odds ratio (OR) of a power athlete harbouring the XX versus the RR genotype compared with sedentary controls was 0.54 [95% confidence interval (CI): 0.34–0.48; P = 0.006]. We also observed that the OR of an endurance athlete having the XX versus the RR genotype compared with power athletes was 1.88 (95%CI: 1.07–3.31; P = 0.028). In endurance athletes, the OR of a “world-class” competitor having the XX genotype versus the RR+RX genotype was 3.74 (95%CI: 1.08–12.94; P = 0.038) compared with those of a lower (“national”) competition level. No association (P>0.1) was noted between the ACTN3 R577X polymorphism and competition level (world-class versus national-level) in power athletes. Our data provide comprehensive support for the influence of the ACTN3 R577X polymorphism on elite athletic performance.  相似文献   

2.
The aim of this pilot study was to investigate the effects of an intervention consisting of mental coaching combined with either electro encephalogram (EEG) alpha power feedback or heart rate variability (HRV) feedback on HRV, EEG outcomes and self-reported factors related to stress, performance, recovery and sleep quality in elite athletes. A prospective pilot study was performed with two distinct cohorts. Soccer players were provided with four sessions of mental coaching combined with daily HRV biofeedback (Group A); track and field athletes were provided with four sessions of mental coaching in combination with daily neurofeedback (Group B). Measurements were performed at baseline, post intervention and at 5 weeks follow-up. Objective measures: EEG and ECG. Subjective measures: Numeric Rating Scale for performance, Pittsburgh Sleep Quality Index, Rest and Stress Questionnaire and Sports Improvement-60. Group characteristics were too distinct to compare the interventions. Linear mixed models were used to analyze differences within groups over time. In Group A, significant changes over time were present in alpha power at 5 of 7 EEG locations (p < 0.01–0.03). LF/HF ratio significantly increased (p = 0.02) and the concentration (p = 0.02) and emotional scale (p = 0.03) of the SIM-60 increased significantly (p = 0.04). In Group B, the HRV low frequency power and recovery scale of the REST-Q significantly increased (p = 0.02 and <0.01 resp.). Other measures remained stable or improved non-significantly. A mental coaching program combined with either HRV or EEG alpha power feedback may increase HRV and alpha power and may lead to better performance-related outcomes and stress reduction. Further research is needed to elucidate the effects of either type of feedback and to compare effects with a control group.  相似文献   

3.
Using the data on five red cell markers (AB0, PGM1, ACP1, GLO1, and ESD) polymorphisms, the population genetic structure of three ethnic territorial groups from the north of European Russia (Continental Nentsy, Kola Saami, and Russian Coast-dwellers) was described. In general, the groups studied a Caucasoid pattern of the frequency distribution of erythrocytic marker alleles. However, a substantial contribution of a Mongoloid component to the Nenets gene pool, expressed as a high frequency of the PGM1*1allele along with a low frequency of the GLO1*1allele, was observed. Three ethnic territorial groups examined were close to one another with respect to the distribution of classical biochemical markers. The interpopulation diversity was low (the mean F ST= 0.015). The differences observed were for the most part caused by the genetic characteristics of Nentsy. The maximum interpopulation diversity was observed for the GLO1*locus (F ST= 0.056).  相似文献   

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6.
Competitive taekwondo composes a high stress situation leading to an increase in the stress hormone cortisol. Little is known about cortisol’s relation to outcome (winning vs. losing) and performance in taekwondo. Therefore, the aim of the study was to investigate cortisol relation to outcome, performance and whether cortisol can predict performance during a competition. Twenty taekwondo combatants (13 males; Mage = 15) provided four salivary samples (C1: 30 min prior, C2: during, C3: after, and C4: 30 min after competition) during an international competition. Total points made in the two rounds during their first fight were used as a performance indicator. Results show no difference in cortisol between winners and losers, before or after competition. However, a negative correlation between performance and C1 as well as C4 was detected. Unexpected, a positive correlation between cortisol during the competition (C2) and performance was identified. A stepwise multiple regression analyses showed that C2 predicted 25.5% of the performance variance. Even if the sample size is relatively small due to the field experimental setting, some conclusions can be drawn to motivate future research. Potentially, in taekwondo it seems advantageous for performance to have higher levels of stress as indicated by cortisol during a competition, whereas particularly before the competition, sport psychological interventions should be provided to combatants to reduce their psychophysiological stress level.  相似文献   

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8.

Objective

Genome-wide association studies have shown that variance in the fat mass- and obesity- associated gene (FTO) is associated with risk of obesity in Europeans and Asians. Since obesity is associated with an increased risk of cardiovascular disease (CVD), several studies have investigated the association between variant in the FTO gene and CVD risk, with inconsistent results. In this study, we performed a meta-analysis to clarify the association of rs9939609 variant (or its proxies [r 2>0.90]) in the FTO gene with CVD risk.

Methods

Published literature from PubMed and Embase was retrieved. Pooled odds ratios with 95% confidence intervals were calculated using the fixed- or random- effects model.

Results

A total of 10 studies (comprising 19,153 CVD cases and 103,720 controls) were included in the meta-analysis. The results indicated that the rs9939609 variant was significantly associated with CVD risk (odds ratio = 1.18, 95% confidence interval = 1.07–1.30, p = 0.001 [Z test], I 2 = 80.6%, p<0.001 [heterogeneity]), and there was an insignificant change after adjustment for body mass index (BMI) and other conventional CVD risk factors (odds ratio = 1.16, 95% confidence interval = 1.05–1.27, p = 0.003 [Z test], I 2 = 75.4%, p<0.001 [heterogeneity]).

Conclusions

The present meta-analysis confirmed the significant association of the rs9939609 variant in the FTO gene with CVD risk, which was independent of BMI and other conventional CVD risk factors.  相似文献   

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This article analyzes black female student athletes' participation in an elite collegiate athletic program and shows how the program maximizes black female participants' athletic and academic potential through surveillance, control, and discipline. The program instills in black female athletes a model of womanhood whereby they come to expect and achieve academic and athletic success, but does so at the expense of their autonomy and freedom from surveillance. Ultimately, this analysis shows the promise and peril of panopticonics as educational technology.  相似文献   

11.

Background

Researches have revealed that the endothelial nitric oxide synthase (eNOS) gene G894T polymorphism is associated with the risk of Myocardial infarction (MI), but the results remain conflicting.

Objective and Methods

A meta-analysis was conducted to investigate the association between eNOS G894T polymorphism and MI. Published studies from PubMed, Embase, CNKI and CBM databases were retrieved. The pooled odds ratios (ORs) for the association between eNOS G894T polymorphism and MI and their corresponding 95% confidence intervals (CIs) were estimated using the random- or fixed- effect model.

Results

A total of 34 studies including 8229 cases and 12839 controls were identified for the meta-analysis. The eNOS G894T polymorphism was significantly associated with MI under a homozygous genetic model (OR = 1.41, 95% CI = 1.08–1.84; P = 0.012), a recessive genetic model (OR = 1.35, 95% CI = 1.06–1.70; P = 0.014), a dominant genetic model (OR = 1.18, 95% CI = 1.04–1.34; P = 0.009). In the subgroup analysis by ethnicity (non-Asian and Asian), no significant association was observed between eNOS G894T polymorphism and MI risk among non-Asians (P>0.05), but a positive significant association was found among Asians (P<0.05).

Conclusions

The eNOS G894T polymorphism is associated with increased MI risk in Asians. The results indicate that ethnicity plays important roles in the association between eNOS G894T polymorphism and MI.  相似文献   

12.
目的:探讨白细胞介素-8(Interleukin-8,IL-8)基因-251A/T位点单核苷酸多态性(Single nucleotide polymorphism,SNP)与急性胰腺炎的关系.方法:应用聚合酶链反应.限制性酶切片段长度多态性技术检测120例急性胰腺炎(Acute pancreatitis,AP)患者和132例健康对照组的IL-8-251A/T基因型分布情况.结果:病例组和对照组均检测到IL-8基因-251A/T位点AA、AT和TT3种基因型:IL-8基因-251A/T的基因型分布在AP组和对照组差另q有统计学意义(P<0.05),AP组等位基因A频率明显增高(24.2%→34.2%);在轻型组和重型组差别有统计学意义(P<0.05),重型组等位基因A频率明显增高(24.2%→42%);在重型合并Ⅰ型和Ⅱ型及SIRS组和非SIRS组各基因型比较差别无统计学意义(P>0.05).结论:IL-8基因-25lA/T基因多态性可能是急性胰腺炎病情进展的危险因素.  相似文献   

13.
目的:探讨FTO基因rs9939609 A/T单核苷酸多态性位点与多囊卵巢综合征易感性及其临床生化特征的相关性。方法:选择102例多囊卵巢综合征患者和96例健康女性作为研究对象并收集其病例临床信息,采用突变敏感性分子开关方法检测各受试者FTO基因rs9939609A/T多态,比较多囊卵巢综合征组与对照组基因型与基因频率的差异,分析基因型与临床生化特征的相关性。结果:rs9939609A/T多态位点共检测到TT、AT、AA三种基因型,其在多囊卵巢综合征组与对照组的频率分别为77.5%、21.5%、1.0%,77.1%12.5%10.4%,两者之间存在显著性差异(P=0.006);等位基因T、A的频率在多囊卵巢综合征组(88.2%、11.8%)与对照组(83.3%、16.7%)之间的分布不具有显著性差异;多囊卵巢综合征组与对照组中,TT与AT+AA两基因型群体的临床和生化特征比较均未发现显著性差异。结论:FTO基因rs9939609 A/T多态位点与PCOS易感性存在相关性。  相似文献   

14.
To assess the significance of various maternal and neonatal factors in the aetiology of neonatal tetany we have investigated the serum calcium, phosphorus, magnesium, and heat-labile alkaline phosphatase of 250 mothers from three ethnic groups at several stages of pregnancy and the serum calcium, phosphorus, and magnesium of many of their infants. Subclinical hypocalcaemia was found to be much commoner in full-term infants on the sixth day of life than is generally appreciated, especially during the winter months and in babies of Asian parents. It is considered that this is a result of high phosphorus loads in artificial milks and is also influenced by maternal vitamin D and possibly calcium intake during pregnancy. The importance of ensuring that Asian women take adequate vitamin D supplements during pregnancy is stressed.  相似文献   

15.

Background and Objectives

Methylenetetrahydrofolate reductase (MTHFR) polymorphism may be a risk factor for male infertility. However, the epidemiologic studies showed inconsistent results regarding MTHFR polymorphism and the risk of male infertility. Therefore, we performed a meta-analysis of published case-control studies to re-examine the controversy.

Methods

Electronic searches of PubMed, EMBASE, Google Scholar and China National Knowledge Infrastructure (CNKI) were conducted to select eligible literatures for this meta-analysis (updated to June 19, 2014). According to our inclusion criteria and the Newcastle-Ottawa Scale (NOS), only high quality studies that observed the association between MTHFR polymorphism and male infertility risk were included. Crude odds ratio (OR) with 95% confidence interval (CI) was used to assess the strength of association between the MTHFR polymorphism and male infertility risk.

Results

Twenty-six studies involving 5,575 cases and 5,447 controls were recruited. Overall, MTHFR 677C>T polymorphism showed significant associations with male infertility risk in both fixed effects (CT+TT vs. CC: OR = 1.34, 95% CI: 1.23–1.46) and random effects models (CT+TT vs. CC: OR = 1.39, 95% CI: 1.19–1.62). Further, when stratified by ethnicity, sperm concentration and control sources, the similar results were observed in Asians, Caucasians, Azoo or OAT subgroup and both in population-based and hospital-based controls. Nevertheless, no significant association was only observed in oligo subgroup.

Conclusions

Our results indicated that the MTHFR polymorphism is associated with an increased risk of male infertility. Further well-designed analytical studies are necessary to confirm our conclusions and evaluate gene-environment interactions with male infertility risk.  相似文献   

16.
Variants in the FTO (oxoglutarate-dependent nucleic acid demethylase) gene have been associated with the BMI determination in Western European and North American populations. To widen the geographical coverage of the FTO studies, we have analyzed the association between the FTO gene variant rs17817449 (G>C) and obesity in a Slavic Eastern European population. A total of 3,079 males and 3,602 females 45-69 years old were randomly selected from population registers of seven Czech cities. We examined three indices of obesity: BMI (kg/m(2)), waist circumference, and waist-to-hip ratio (WHR). The FTO rs17817449 variant was significantly associated with BMI both in males (GG 28.7 +/- 4.1; GT 28.3 +/- 3.9; TT 28.0 +/- 3.9; P = 0.003) and females (GG 28.7 +/- 5.2; GT 28.2 +/- 5.1; TT 27.2 +/- 4.9; P < 0.001); the associations were not affected by adjustment for age, smoking, socioeconomic status, and physical activity. The FTO variant was also associated with waist circumference (difference between GG and TT was 1.1 cm (P = 0.043) in men and 2.4 cm (P < 0.001) in women) but this relationship disappeared after adjustment for BMI. Similarly, BMI explained the weak association of FTO with WHR and C-reactive protein. FTO was not associated with plasma total and high-density lipoprotein cholesterol, triglycerides, blood glucose, and blood pressure. These results confirm that in a Slavic population the FTO variant is strongly associated with BMI but not with other risk factors.  相似文献   

17.

Aims

Many studies have investigated the relationship between FTO gene polymorphism and polycystic ovary syndrome (PCOS) susceptibility but revealed mixed results. In this study, we aimed to perform a meta-analysis to clarify this association.

Methods

Published literature from PubMed, Embase and CNKI was retrieved. Meta-analysis was performed to calculate pooled odds ratio (OR) with 95% confidence interval (CI) using the random- or fix- effects model.

Results

A total of 5 studies (4778 cases and 4272 controls) were included in our meta-analysis. The results suggested that FTO rs9939609 polymorphism (or its proxy) was marginally associated with PCOS risk after adjustment for body mass index (BMI) (OR = 1.26; 95%CI: 1.02–1.55). However, the marginal association was not stable after sensitivity analysis. In the subgroup analysis by ethnicity, the association was significant in East Asians (OR = 1.43, 95%CI = 1.30–1.59) but not in Caucasians (OR = 1.04, 95%CI = 0.85–1.29).

Conclusions

Our present meta-analysis indicated that FTO rs9939609 polymorphism (or its proxy) might not be associated with risk of PCOS in overall population. However, in East Asians, there might be a direct association between FTO variant and PCOS risk, which is independent of BMI (adiposity).  相似文献   

18.
目的:旨在探讨PRODH基因与汉族人群精神分裂症的时空联系。方法:采用聚合酶链式反应—限制性片断长度多态性方法,分析330例精神分裂症患者和344例正常对照者中PRODH*1945(T/C)多态性的基因型,比较病例组与对照组之间该多态性的基因型及等位基因的频率差异,进一步分析携带不同基因型的精神分裂症患者的发病年龄。结果:与正常对照组相比,精神分裂症患者PRODH*1945(T/C)多态性的基因型(x2=8.171,df=2,p=0.016)和等位基因(C>T,x2=5.249,df=1,p=0.021,OR=1.37,95%CI:0.56-0.96)的频率差异有统计学意义,携带风险等位基因C的精神分裂症患者发病年龄小于携带T者,差异存在弱显著性(CC CT:20.43 4.71岁,TT:22.57±5.23岁,t=-2.173,p=0.045)。结论:PRODH*1945(T/C)基因多态性可能参与精神分裂症发病机制及影响精神分裂症的发病年龄。  相似文献   

19.
Evolutionary radiations, times of profound diversification of species against a broader background of more muted evolutionary change, have long been considered one of the fundamental patterns in the fossil record. Further, given the important role geological, environmental, and climatic processes play in causing speciation, analyzing the biogeographic context of radiations can yield important insight into their evolutionary mechanisms. In this study we examine biogeographic patterns and quantify rates of speciation in a diverse group of Devonian trilobites, the calmoniids, that has been hailed as a classic paleontological example of an evolutionary radiation. In particular, a phylogenetic biogeographic analysis—modified Brooks Parsimony Analysis—was used to examine the processes and geographic setting of speciation within the group. Results indicate that the Malvinokaffric Realm was a geographically complex area, and this geographic complexity created various opportunities for speciation via geodispersal and vicariance that created the fuel that fed the speciation in these taxa. Part of the geographic complexity was created not only by the inherent geologic backdrop of the region, but the overlying changes of sea level rise and fall. Rates of speciation were highest when sea level was lowest. Low sea level encouraged isolation of faunas in different tectonic basins. By contrast, sea level rise facilitated range expansion and geodispersal to other distinct tectonic basins, and speciation rates concomitantly fell; however, the taxa with the expanded ranges were later fodder for diversification when sea level fell again. Here we present a view of evolutionary radiations driven fundamentally by external abiotic factors—geology and climate—that cause range expansion and opportunities for geographic isolation with resultant rapid speciation.  相似文献   

20.
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