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91.

Purpose

We investigated the influence of Leptin (LEP) and leptin receptor (LEPR) SNPs on habitual physical activity (PA) and body composition response to a unilateral, upper body resistance training (RT) program.

Methods

European-derived American volunteers (men = 111, women = 131, 23.4 ± 5.4 yr, 24.4 ± 4.6 kg·m− 2) were genotyped for LEP 19 G>A (rs2167270), and LEPR 326 A>G (rs1137100), 668 A>G (rs1137101), 3057 G>A (rs1805096), and 1968 G>C (rs8179183). They completed the Paffenbarger PA Questionnaire. Arm muscle and subcutaneous fat volumes were measured before and after 12 wk of supervised RT with MRI. Multivariate and repeated measures ANCOVA tested differences among phenotypes by genotype and gender with age and body mass index as covariates.

Results

Adults with the LEP 19 GG genotype reported more kcal/wk in vigorous intensity PA (1273.3 ± 176.8, p = 0.017) and sports/recreation (1922.8 ± 226.0, p < 0.04) than A allele carriers (718.0 ± 147.2, 1328.6 ± 188.2, respectively). Those with the LEP 19 GG genotype spent more h/wk in light intensity PA (39.7 ± 1.6) than A allele carriers (35.0 ± 1.4, p = 0.03). In response to RT, adults with the LEPR 668 G allele gained greater arm muscle volume (67,687.05 ± 3186.7 vs. 52,321.87 ± 5125.05 mm3, p = 0.01) and subcutaneous fat volume (10,599.89 ± 3683.57 vs. − 5224.73 ± 5923.98 mm3, p = 0.02) than adults with the LEPR 668 AA genotype, respectively.

Conclusion

LEP19 G>A and LEPR 668 A>G associated with habitual PA and the body composition response to RT. These LEP and LEPR SNPs are located in coding exons likely influencing LEP and LEPR function. Further investigation is needed to confirm our findings and establish mechanisms for LEP and LEPR genotype and PA and body composition associations we observed.  相似文献   
92.
Donation of human tissue for transplant and research has historically been facilitated within the hospital mortuary. In 2006 NHSBT Tissue Services opened the Dedicated Donation Facility [DDF], the first facility in the UK dedicated to the donation of tissues under strictly controlled conditions. Nine family members who had agreed and experienced the transfer of their deceased relative to the DDF for tissue donation participated in a service evaluation applying qualitative data collection methods and framework analysis. The evaluation aimed to: understand the decision-making process of family members who agreed to their deceased relative being moved to the DDR for tissue donation; identify any concerns that family members had; gather the views of family members regarding the 'service' provided to them by NHSBT Tissue Services. Family members were unaware of the possibility of tissue donation. The process of reasoning behind both agreeing to tissue donation and movement of the deceased to the DDF by family members was fundamentally, 'the benefit to others' that tissue donation would bring, and fulfilling the wishes of the deceased [when known]. Family decision making was facilitated by: (i) a positive rapport with the requester, (ii) satisfaction with the information provided to the family about what would happen, and (iii) trust in that what was being said would happen. Family members were satisfied with the service provided to them by Tissue Services and confident in agreeing to the transfer of their deceased relative to the dedicated facility for tissue donation.  相似文献   
93.
To better understand lung oxidant stress responses, we examined A549 lung cells exposed to H2O2 using “stable isotope labeling by amino acids.” We identified 466 cytosolic and 387 nuclear proteins; H2O2 exposure produced ≥twofold differences in 31, all were downregulations. None were previously reported as oxidant stress response proteins, although they share common functions. One of the responders, treacle, was linked to p53, an important oxidative stress response. The Treacher Collins–Franceschetti syndrome can result from treacle mutation and insufficiency was suggested to cause increased p53 leading to the syndrome. However, results here indicate p53 and treacle responses to H2O2 are independent: treacle remains suppressed after p53 recovery; the threshold for treacle reduction is well above that for p53 induction; and treacle suppression by short interfering RNA does not modify the p53 response. Evidence of treacle antioxidant activity include reduction being driven by proteasome degradation independently of mRNA, typical for oxidant‐absorbing proteins, and increased sensitivity to H2O2 consequent to short interfering RNA suppression. Data here show a link between oxidative stress and treacle reduction, demonstrate that treacle does not control p53, provide evidence of a treacle oxidant defense role, support the hypothesis that oxidant stress plays a role in the Treacher Collins–Franceschetti syndrome, and raise the possibility that treacle plays an anti‐oxidant role in lungs.  相似文献   
94.
A range of watercress (Rorippa nasturtium-aquaticum) explants (stems, hypocotyls, true-leaves, cotyledons and petioles) were tested for their capacity to regenerate adventitious shoots from callus formed using Murashige and Skoog medium containing different concentrations of thidiazuron and 2,4-dichlorophenoxyacetic acid. The highest shoot regeneration rate was a mean of 18 shoots per responding explant from stem callus formed on medium containing 5 μM thidiazuron and 0.05 μM 2,4-dichlorophenoxyacetic acid. A histological study confirmed that shoots originated directly from callus tissue. Twenty five percent of somaclones exhibited somaclonal variation in leaf shape, plant height, axillary branching or ploidy. The variation in 6% of somaclones was heritable to the first selfed generation. A screening protocol was developed to permit the identification of somaclones with increased resistance to the economically damaging watercress root pathogen, Spongospora subterranea f. sp. nasturtii. Although 883 somaclones were screened using this protocol, no significant increase in disease resistance was detected. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
95.
Mouse blood and serum contain a synergistic factor which affects both the speed and completeness of destruction of Trypanosoma brucei in the presence of salicylhydroxamic acid (SHAM) and glycerol. The action of this factor is dose dependent producing complete killing in infected whole blood with 2 mM SHAM and 12 mM glycerol but not in a mixture of 20% infected whole blood and 80% buffer containing the same final concentration of SHAM and glycerol. This factor may account for the discrepancy in reports showing that SHAM-glycerol does not kill 100% of the exposed parasites in vitro yet is able to cure infected animals. The factor is not due to an acquired immune response, complement action, nor lipoproteins. Should the level of the factor be able to be increased, this could greatly increase the effectiveness of SHAM-glycerol.  相似文献   
96.
Pseudomonas fluorescens strain 220 is an effective antagonist of Pseudocercosporella herpotrichoides , the eyespot pathogen of cereals. Culture filtrates of Ps. fluorescens 220 were inhibitory to spore germination and hyphal growth of P. herpotrichoides and at least two compounds with antifungal and antibacterial activity were identified in cultures grown in nutrient broth. In plant tests, both a culture broth of Ps. fluorescens 220 and a crude antibiotic extract reduced eyespot disease, whereas a mutant strain of 220 deficient in antibiotic production had no effect. Production of antibiotics would therefore appear to be a major factor in the suppression of P. herpotrichoides infection. A loss of disease control when Ps. fluorescens 220 was applied to plants in water was not due to lack of survival, as populations of a marked strain of Ps. fluorescens 220 applied to the stem base of wheat plants were similar whether applied in water or culture broth.  相似文献   
97.
Ecological restoration in urban environments in New Zealand   总被引:1,自引:0,他引:1       下载免费PDF全文
In the last two decades, the research and practice of restoration in New Zealand has extended into urban ecosystems, where it presents unique challenges and opportunities. This account reviews the history and current state of ecological restoration in urban environments in a country with one of the longest traditions of restoration in the world.  相似文献   
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