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981.
While recent works aimed to thoroughly characterize the bacterial community of the human anterior nares of a few candidates, this work sought to analyse a greater cross-section by sampling 100 volunteers. After optimizing and validating the method of terminal restriction fragment length polymorphism against six previously pyrosequenced samples, abundant species could be discriminated and their relative abundances measured in a high-throughput manner. The 100 volunteers could be statistically clustered into 12 groups, where two-thirds of volunteers shared more than 40% similarity in respect to their bacterial community structure, while the remaining third clustered into smaller groups being dominated by Dolosigranulum pigrum, Moraxella spp. or Staphylococcus aureus. Moraxella spp. was present predominantly in women rather than in men. The use of network analysis charting bacterial ecological co-occurrences revealed new evidence of likely positive associations between some core human nasal species. So, in the age of post 'omics' and 'deep sequencing', there is still a place for these well-tried and well-tested methods that can offer a rapid, reproducible and economical alternative, whereby also yielding valuable new information.  相似文献   
982.
Fish oil rich in n-3 polyunsaturated fatty acids is known to attenuate diet-induced obesity and adipose tissue inflammation in rodents. Here we aimed to investigate whether different carbohydrate sources modulated the antiobesity effects of fish oil. By feeding C57BL/6J mice isocaloric high-fat diets enriched with fish oil for 6 wk, we show that increasing amounts of sucrose in the diets dose-dependently increased energy efficiency and white adipose tissue (WAT) mass. Mice receiving fructose had about 50% less WAT mass than mice fed a high fish oil diet supplemented with either glucose or sucrose, indicating that the glucose moiety of sucrose was responsible for the obesity-promoting effect of sucrose. To investigate whether the obesogenic effect of sucrose and glucose was related to stimulation of insulin secretion, we combined fish oil with high and low glycemic index (GI) starches. Mice receiving the fish oil diet containing the low-GI starch had significantly less WAT than mice fed high-GI starch. Moreover, inhibition of insulin secretion by administration of nifedipine significantly reduced WAT mass in mice fed a high-fish oil diet in combination with sucrose. Our data show that the macronutrient composition of the diet modulates the effects of fish oil. Fish oil combined with sucrose, glucose, or high-GI starch promotes obesity, and the reported anti-inflammatory actions of fish oil are abrogated. In conclusion, our data indicate that glycemic control of insulin secretion modulates metabolic effects of fish oil by demonstrating that high-GI carbohydrates attenuate the antiobesity effects of fish oil.  相似文献   
983.
984.
985.
Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have long been associated with decreased inflammation and are also implicated in the prevention of tumorigenesis. Conventional thinking attributed this mainly to a suppressive effect of these fatty acids on the formation of arachidonic acid-derived prostaglandins and leukotrienes. Recent years have seen the discovery of a new class of inflammation-dampening and resolution-promoting n-3 PUFA-derived lipid mediators called resolvins and protectins. Chemically, these compounds are hydroxylated derivatives of the parent n-3 PUFA eicosapentaenoic acid (EPA) for the E-resolvins, and docosahexaenoic acid (DHA) for the D-resolvins and protectin D1. While a relatively large number of these compounds have been identified and characterized until now, with differences in the positions of the hydroxyl-groups as well as in the chirality at the different carbon atoms, all compounds share common precursor metabolites, 17-hydroperoxydocosahexaenoic acid (17-H(p)DHA) for the DHA-derived compounds and 18-hydroperoxyeicosapentaenoic acid (18-H(p)EPE) for the EPA-derived compounds. In this review we summarize the current knowledge about EPA- and DHA-derived resolvins and protectins and explore the potential use of the pro-resolvins 17-hydroxydocosahexaenoic acid (17-HDHA) and 18-hydroxyeicosapentaenoic acid (18-HEPE) as indicators of anti-inflammatory n-3 PUFA mediator formation.  相似文献   
986.
987.
Transepithelial transport mechanisms play a key role in regulating the absorption and secretion of calcium (Ca2 +) and inorganic phosphate (Pi) in the gastrointestinal tract. Although intestinal disorders with imbalances in macromineral homeostasis are frequently observed in horses, available data on intestinal Ca2 + and Pi transport are limited. The aim of the present study was to characterize the intestinal Ca2 + and Pi transport functionally by using the in vitro radioisotope tracer technique with Ussing chambers and to identify components involved in Ca2 + transport at both mRNA and protein level. Among the different intestinal segments, the duodenum showed significant and highest active Ca2 + absorption. The findings from RT-PCR and Western blot analysis suggest that the epithelial Ca2 + channel TRPV6, the cytosolic calcium binding protein calbindin-D9K and the plasma membrane calcium ATPase PMCA may be involved in active transcellular Ca2 + transport. Regarding the Pi transport, the results indicate significant active Pi secretion in the jejunum, but the contributing mechanisms remain unclear. A significant inhibiting effect of ouabain as an antagonist of the basolateral Na+/K+-ATPase on the serosal-to-mucosal Pi transport suggests a pivotal role of Na+ in jejunal Pi transport in the horse.  相似文献   
988.
The study was performed in order to determine whether peripheral blood monocyte in vitro function, and lymphocyte in vivo activation at diagnosis, was associated with HPV tumor infection status and 15-year survival in head and neck squamous cell carcinoma (HNSCC) patients. Sixty-five patients from a consecutive cohort of newly diagnosed HNSCCs, together with 18 control patients, were included in the study. Monocyte responsiveness was assessed by measuring monocyte in vitro interleukin (IL)-6 secretions after 24 hours of LPS stimulation in cultures with a serum-free medium. T lymphocyte activation was determined as the fraction of CD71-positive cells on CD3-positive cells by flow cytometry, whereas HPV infection was determined by PCR on formalin-fixed paraffin-embedded (FFPE) tumor tissue. Disease-specific survivals and overall survivals were determined 15 years following inclusion. HPV-positive HNSCC patients had a lower monocyte LPS-stimulated IL-6 response. A high LPS-stimulated monocyte IL-6 response predicted a decreased survival rate (P=0.019). A high percentage of CD71-positive T lymphocytes also predicted an impaired prognosis (P=0.021). The predictive power of IL-6 monocyte LPS-stimulated responses was retained when adjusted for age, gender and TNM stage of the patients. The monocyte and T lymphocyte survival predictions were independent of each other. The survival was particularly low with a combined high activated monocyte and T lymphocyte status. In a multivariate analysis, IL-6 secretion and the percentage of CD71-positive T lymphocytes both uniquely predicted survival independent of HPV infection status. It is postulated that the natural and adaptive immune systems are separately and additionally linked to the clinical aggressiveness of HNSCCs.  相似文献   
989.
The objectives of this study were to examine the effects of a moderate intensity strength training on changes in critical velocity (CV), anaerobic running distance (D''), sprint performance and Yo-Yo intermittent running test (Yo-Yo IR1) performances. Methods: two recreational soccer teams were divided in a soccer training only group (SO; n = 13) and a strength and soccer training group (ST; n = 13). Both groups were tested for values of CV, D'', Yo-Yo IR1 distance and 30-m sprint time on two separate occasions (pre and post intervention). The ST group performed a concurrent 6-week upper and lower body strength and soccer training, whilst the SO group performed a soccer only training. Results: after the re-test of all variables, the ST demonstrated significant improvements for both, YoYo IR1 distance (p = 0.002) and CV values (p<0.001) with no significant changes in the SO group. 30-m sprint performance were slightly improved in the ST group with significantly decreased performance times identified in the SO group (p<0.001). Values for D'' were slightly reduced in both groups (ST -44.5 m, 95% CI = -90.6 to 1.6; SO -42.6 m, 95% CI = -88.7 to 3.5). Conclusions: combining a 6-week moderate strength training with soccer training significantly improves CV, Yo-Yo IR1 whilst moderately improving 30-m sprint performances in non-previously resistance trained male soccer players. Critical Velocity can be recommended to coaches as an additional valid testing tool in soccer.  相似文献   
990.
UV-absorbing mycosporine-like amino acid compounds (MAA) were identified and quantified in 13 macroalgal Chlorophyceae, six Phaeophyceae and 28 Rhodophy-ceae collected in the intertidal zone from the tropical island Hainan, People's Republic of China, as well as from tropical mangrove locations in America, Africa, Australia and Japan. All of these habitats receive naturally high solar ultraviolet (UV) irradiances. The study revealed that all Rhodophyceae contained several MAA, which are assumed to function as natural UV sunscreens. Within all species investigated eight distinct compounds were found, seven of which were identified as mycosporine-glycine, shinorine, porphyra-334, pal-ythine, asterina-330, palythinol and palythene. The unknown substance had an absorption spectrum with a maximum at 357 nm. This compound was restricted to two red algal species from Hainan. In contrast, the Chlorophyceae and Phaeophyceae did not contain MAA or exhibited only trace concentrations. Compared with data from the literature, the amount of all MAA in the tropical Rhodophyceae seemed to be higher than in temperate organisms, probably reflecting acclimation to the stronger solar radiation which is typical for lower latitudes. The data suggest that accumulation of MAA may represent a natural defence system against exposure to biologically harmful UV radiation.  相似文献   
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