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61.
Intense exercise induces inflammatory-like changes and oxidative stress in immune cells. Our aim was to study the effects of antioxidant diet supplementation on the neutrophil inflammatory response and on the tocopherol associated protein (TAP) expression after exhaustive exercise. Fourteen male-trained amateur runners were randomly divided in two placebo and supplemented groups. Vitamins C (152 mg/d) and E (50 mg/d) supplementation were administrated to the athletes for a month, using an almond based isotonic and energetic beverage. Non-enriched beverage was given to the placebo group. After one month, the subjects participated in a half-marathon race (21 km-run). Neutrophil TAP mRNA expression and markers of the inflammatory response were determined before, immediately after, and 3 h after finishing the half-marathon race. TAP expression increased after exercise mainly in the neutrophils of the placebo group. Exercise induced an inflammatory response in both placebo and supplemented groups, manifested with neutrophilia, increased creatine kinase and lactate dehydrogenase serum activities, neutrophil luminol chemiluminescence and myeloperoxidase release. Plasma malondialdehyde only increased in the placebo group after exercise. Diet supplementation with moderate levels of antioxidant vitamins avoids plasma damage in response to exhaustive exercise without the effects on the inflammatory process. Neutrophil degranulation and increased tocopherol associated protein could contribute to the neutrophil protection from the oxidative stress.  相似文献   
62.
Proteins responsive to androgen and anti-androgen may be involved in the development and progression of prostate cancer and the ultimate failure of androgen-ablation therapy. These proteins represent potential diagnostic and therapeutic targets for improved management of prostate cancer. We have investigated the effect of androgen (R1881) and anti-androgen (bicalutamide) on the androgen-responsive prostate cancer LNCaP cell line using a quantitative gel-based proteomic approach. Prior to analysis, the in vitro system was evaluated for reproducibility and validated by appropriate molecular responses to treatment. Six replicate samples were independently generated and analysed by 2-D DIGE. According to strict statistical criteria, 197 spots were differentially expressed, of which we have successfully identified 165 spots corresponding to 125 distinct proteins. Following androgen supplementation, 108 spots (68 proteins) were increased and 57 spots (39 proteins) were decreased. Essentially no difference was observed between control and anti-androgen-treated samples, confirming the absence of "off-target" effects of bicalutamide. Identified proteins were involved in diverse processes including the stress response and intracellular signalling. The potential contribution to disease of these processes and identified constituent proteins are discussed. This rigorous, statistically supported study of androgen responses has provided a number of potential candidates for development as diagnostic/prognostic markers and drug targets.  相似文献   
63.
This study was designed to determine the expression pattern of estrogen receptor (ER) subtypes in the Acomys cahirinus ovarian cells during its postnatal development. Immunohistochemical studies revealed the presence of ERα and ERβ in germinal epithelium cells and interstitial tissue. Both these ER subtypes were also seen in granulosa cells and oocytes of growing follicles, however, the level of ERβ expression was higher in comparison with ERα. In contrast to ERβ, ERα protein was also present in theca cells. The expression of ERs increased with animals’ age, but it decreased during follicular maturation. Moreover, the immunolocalization of ER subtypes in luteal cells showed that not ERβ, but ERα expression is up-regulated throughout corpus luteum development. These immunohistochemical studies demonstrate, for the first time, that ERα is also expressed in the mouse granulosa cells and it may be a mediator of estrogen action in granulosa cells proliferation and differentiation.  相似文献   
64.
Dozens of morphologically differentiated populations, subspecies and species of crossbills (genus Loxia) exist. It has been suggested that this divergence is due to variation in the conifer cones that each population specialises upon, requiring a specific beak size to efficiently separate the cone scales. If so, apparent survival should depend on beak size. To test this hypothesis, we undertook multievent capture–recapture modelling for 6844 individuals monitored during 27 years in a Pyrenean common crossbill L. curvirostra population in a forest of mountain pine Pinus uncinata. Apparent survival was indeed related to beak width, resulting in stabilizing selection around an optimum that was close to the observed mean beak width, indicating that local crossbill beak morphology is adapted to the conifer they feed upon. Both natural selection (selective mortality) and selective emigration of maladapted individuals may explain our findings. As is often the case in capture–recapture analyses but rarely recognised, we could not formally decompose apparent survival into selective mortality versus selective permanent emigration. Nonetheless, there are several indications that selective permanent emigration should not be fully excluded. First, natural selection by itself would have to be unusually strong compared to other empirical estimates to create the observed pattern of apparent survival. Second, the observed mean beak width was a bit lower than the estimated optimum beak width. This can be explained by immigration of crossbills with smaller beaks originating from southern populations, which may subsequently have left the study area permanently in response to low food intake. This is in line with a detected transient effect in the data, yet apparently little influx from crossbills from northern Europe. When permanent emigration is phenotypically selective this will have ecological and evolutionary consequences, so this possibility deserves more attention in general.  相似文献   
65.
66.
A total of 1975 school-children on the island of Krk aged 7-19 years of life were included in this study. The purpose was to establish the goitre status and plasmatic level of vitamins A and E in the examined children with the enlarged thyroid gland. The goitre prevalence was 29.8%. The average plasmatic values of vitamins A and E in the children with enlarged thyroids were statistically significantly lower from the reference values. Mentioned goitre prevalence at the level of moderate and heavier endemic goitre speaks on behalf of alimentary iodine deficiency. But the goiter examinations suggested the idoine deficiency not to be the only etiological factor of goitre on the island of Krk. Lower average plasmatic values of vitamins A and E in the examined with the enlarged thyroids referred to this fact to a certain degree.  相似文献   
67.
Oxidative stress induced by hypoxia/reoxygenation mediates the pathophysiological consequence of ischemia/reperfusion and human diseases. Diving apnea could be a good model of oxidative stress induced by hypoxia/reoxygenation. We studied the influence of vitamin C diet supplementation on the response of neutrophil antioxidant defenses, NO production, and redox status to diving apnea. Seven professional apnea divers participated in a double-blind cross study. Divers were assigned to either vitamin C-supplemented (1 g/d for a week) or placebo groups. Blood samples were taken under basal conditions, immediately after diving apnea for 4 h and after 1 h of recovery. Plasma vitamin C increased only in the supplemented group after diving and was maintained high in recovery. Diving apnea decreased neutrophil GSH/GSSG ratio in both groups, but maintained protein carbonyl derivates. Neutrophil catalase activity and levels and glutathione peroxidase activity were lower in the supplemented group than in the placebo group after diving. iNOS and nitrite levels decreased only in the supplemented group after diving and recovery. Diving apnea induced oxidative stress and initiated neutrophil reactions that resemble the acute-phase immune response with increased myeloperoxidase activity in neutrophils. Diet supplementation with vitamin C reduced neutrophil iNOS levels and NO production.  相似文献   
68.
Linkage disequilibrium (LD) at the adh1 locus was examined in two sets of maize inbreds. A set of 32 was chosen to represent most of the genetic diversity in the cultivated North American elite maize breeding pool. A second set of 192 inbreds was chosen to sample more deeply the two major heterotic groups in elite maize germplasm. Analysis of several loci in the vicinity of the adh1 gene shows that LD as measured by D and r2 extends greater than 500 kbp in this germplasm. The presence of this exceptionally long segment of high LD may be suggestive of selection acting on one of the genes in the vicinity of adh1 or of a locally reduced rate of recombination.Electronic Supplementary Material Supplementary material is available for this article at .  相似文献   
69.
A photosynthetic microbial mat was investigated in a large pond of a Mediterranean saltern (Salins-de-Giraud, Camargue, France) having water salinity from 70 per thousand to 150 per thousand (w/v). Analysis of characteristic biomarkers (e.g., major microbial fatty acids, hydrocarbons, alcohols and alkenones) revealed that cyanobacteria were the major component of the pond, in addition to diatoms and other algae. Functional bacterial groups involved in the sulfur cycle could be correlated to these biomarkers, i.e. sulfate-reducing, sulfur-oxidizing and anoxygenic phototrophic bacteria. In the first 0.5 mm of the mat, a high rate of photosynthesis showed the activity of oxygenic phototrophs in the surface layer. Ten different cyanobacterial populations were detected with confocal laser scanning microscopy: six filamentous species, with Microcoleus chthonoplastes and Halomicronema excentricum as dominant (73% of total counts); and four unicellular types affiliated to Microcystis, Chroococcus, Gloeocapsa, and Synechocystis (27% of total counts). Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments confirmed the presence of Microcoleus, Oscillatoria, and Leptolyngbya strains (Halomicronema was not detected here) and revealed additional presence of Phormidium, Pleurocapsa and Calotrix types. Spectral scalar irradiance measurements did not reveal a particular zonation of cyanobacteria, purple or green bacteria in the first millimeter of the mat. Terminal-restriction fragment length polymorphism analysis of PCR-amplified 16S rRNA gene fragments of bacteria depicted the community composition and a fine-scale depth-distribution of at least five different populations of anoxygenic phototrophs and at least three types of sulfate-reducing bacteria along the microgradients of oxygen and light inside the microbial mat.  相似文献   
70.
Two species with genomes of almost identical size, maize and human, have different evolutionary histories, and as a result their genomes differ greatly in their content of retroelements, average size of the genes and amount of genetic diversity. However, there are also significant similarities: they both have undergone bottlenecks during their recent history and seem to have non-uniform distribution of recombination events. The human genome has been shown to contain large linkage blocks characterized by a limited number of haplotypes. A similar linkage block structure is likely to exist in maize. Although highly diverse maize populations show rapid decline of linkage disequilibrium, as in humans, it is possible to define populations with strong linkage disequilibrium, suitable for whole-genome scan association mapping. The genetic diversity and lack of sequence homology found in maize influences recombinational properties and local linkage disequilibrium levels but also challenges our understanding of the relationship between the genome sequence and species definition.  相似文献   
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