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911.

Objectives

Polyphenol supplementation was tested as a countermeasure to inflammation and oxidative stress induced by 3-d intensified training.

Methods

Water soluble polyphenols from blueberry and green tea extracts were captured onto a polyphenol soy protein complex (PSPC). Subjects were recruited, and included 38 long-distance runners ages 19–45 years who regularly competed in road races. Runners successfully completing orientation and baseline testing (N = 35) were randomized to 40 g/d PSPC (N = 17) (2,136 mg/d gallic acid equivalents) or placebo (N = 18) for 17 d using double-blinded methods and a parallel group design, with a 3-d running period inserted at day 14 (2.5 h/d, 70% VO2max). Blood samples were collected pre- and post-14 d supplementation, and immediately and 14 h after the third day of running in subjects completing all aspects of the study (N = 16 PSPC, N = 15 placebo), and analyzed using a metabolomics platform with GC-MS and LC-MS.

Results

Metabolites characteristic of gut bacteria metabolism of polyphenols were increased with PSPC and 3 d running (e.g., hippurate, 4-hydroxyhippurate, 4-methylcatechol sulfate, 1.8-, 1.9-, 2.5-fold, respectively, P<0.05), an effect which persisted for 14-h post-exercise. Fatty acid oxidation and ketogenesis were induced by exercise in both groups, with more ketones at 14-h post-exercise in PSPC (3-hydroxybutyrate, 1.8-fold, P<0.05). Established biomarkers for inflammation (CRP, cytokines) and oxidative stress (protein carbonyls) did not differ between groups.

Conclusions

PSPC supplementation over a 17-d period did not alter established biomarkers for inflammation and oxidative stress but was linked to an enhanced gut-derived phenolic signature and ketogenesis in runners during recovery from 3-d heavy exertion.

Trial Registration

ClinicalTrials.gov, U.S. National Institutes of Health, identifier: NCT01775384  相似文献   
912.
Krukenberg tumor originated from stomach in female patients is common in clinical practice, but it is still uncertain whether surgical resection of ovarian metastases could improve the outcome. Some studies suggested that a certain group of patients could benefit from the resection of ovarian metastases. However, conclusions were different between studies and there was no data to illustrate if certain molecular markers were associated with patients’ survival. In this study, we analyzed the effects of resection of ovarian metastases, and investigated prognostic factors in 133 patients with ovarian metastases originated from stomach. Furthermore, we examined the expression of some cancer stem cells (CSCs) markers or related molecules in 64 ovarian metastases specimens and analyzed the correlation between these molecules and patients’ survival. We found that the median overall survival (mOS) of all 133 patients was 16 months, and “gastrectomy” and “without ascites” were two independent prognostic factors associated with longer survival. The mOS of the patients with gastrectomy was longer than that of patients had not undergone gastrectomy (19 vs. 9 months, p = 0.048). Patients without ascites survived longer than those with ascites (mOS: 21 vs. 13 months, p = 0.008). We also found that Sox2, CD44 or CD133 positive expression in ovarian metastases were risk factors correlated with poor survival, and Sox2 expression was an independent prognostic indicator. These results suggested that ovarian metastasectomy might help to prolong the survivor of some patients with Krukenberg tumor originated from stomach. Patients without ascites, and with resected or resectable primary gastric cancer lesion could get benefit from and be potential candidate for surgical treatment. The expression of Sox2 might serve as a prognostic indicator for predicting patients’ survival and be helpful for selecting patients in future.  相似文献   
913.

Background

The I405V polymorphism of the cholesteryl ester transfer protein gene (CETP) has been suggested to be a protective factor conferring longevity in Ashkenazi Jews, although findings in other races are not supportive. This paper describes a case-control study and a meta-analysis conducted to derive a more precise estimation of the association between CETP 405V and longevity.

Methods

We enrolled 1,021 ethnic Han Chinese participants (506 in the longevity group and 515 controls), then performed a meta-analysis that integrated the current study and previously published ones. Pooled odds ratios (OR) were calculated for allele contrasts, dominant and recessive inheritance models to assess the association between CETP 405V and longevity according to the ethnic stratification.

Results

Our case-control data indicated that CETP 405V is a longevity risk allele in all genetic models (P additive=0.008; P dominant=0.008, ORdominant=0.673; P recessive=0.017, ORrecessive=0.654) after adjustment for the apolipoprotein E (APOE) ε4 allele, body mass index and high-density lipoprotein cholesterol. A synergy was detected between 405V and APOE ε4 (P=0.001, OR=0.530). Eight studies were eligible for meta-analysis, which confirmed 405V is the risky allele against longevity in all genetic models: allele contrasts (OR=0.81, 95%CI=0.74-0.88), dominant model (OR=0.72, 95%CI=0.64-0.82) and recessive model (OR=0.80, 95%CI=0.67-0.96). After ethnic stratification, 405V remained a risk allele in East Asians but no significant association was found in Europeans or white Americans.

Conclusion

Our case-control study suggests CETP 405V as a risk allele against longevity in Chinese. The meta-analysis suggests the involvement of CETP 405V is protective in Ashkenazi Jews but is a risk allele against longevity in the East Asian (Chinese) population.  相似文献   
914.
The mu-opioid receptor (MOR) is the G-protein coupled receptor primarily responsible for mediating the analgesic and rewarding properties of opioid agonist drugs such as morphine, fentanyl, and heroin. We have utilized a combination of traditional and modified membrane yeast two-hybrid screening methods to identify a cohort of novel MOR interacting proteins (MORIPs). The interaction between the MOR and a subset of MORIPs was validated in pulldown, co-immunoprecipitation, and co-localization studies using HEK293 cells stably expressing the MOR as well as rodent brain. Additionally, a subset of MORIPs was found capable of interaction with the delta and kappa opioid receptors, suggesting that they may represent general opioid receptor interacting proteins (ORIPS). Expression of several MORIPs was altered in specific mouse brain regions after chronic treatment with morphine, suggesting that these proteins may play a role in response to opioid agonist drugs. Based on the known function of these newly identified MORIPs, the interactions forming the MOR signalplex are hypothesized to be important for MOR signaling and intracellular trafficking. Understanding the molecular complexity of MOR/MORIP interactions provides a conceptual framework for defining the cellular mechanisms of MOR signaling in brain and may be critical for determining the physiological basis of opioid tolerance and addiction.  相似文献   
915.
Abiotic stresses greatly influence plant growth and productivity. While glycosyltransferases are widely distributed in plant kingdom, their biological roles in response to abiotic stresses are largely unknown. In this study, a novel Arabidopsis glycosyltransferase gene UGT85A5 was identified as significantly induced by salt stress. Ectopic expression of UGT85A5 in tobacco enhanced the salt stress tolerance in the transgenic plants. There were higher seed germination rates, better plant growth and less chlorophyll loss in transgenic lines compared to wild type plants under salt stress. This enhanced tolerance of salt stress was correlated with increased accumulations of proline and soluble sugars, but with decreases in malondialdehyde accumulation and Na+/K+ ratio in UGT85A5-expressing tobacco. Furthermore, during salt stress, expression of several carbohydrate metabolism-related genes including those for sucrose synthase, sucrose-phosphate synthase, hexose transporter and a group2 LEA protein were obviously upregulated in UGT85A5-expressing transgenic plants compared with wild type controls. Thus, these findings suggest a specific protective role of this glycosyltransferase against salt stress and provide a genetic engineering strategy to improve salt tolerance of crops.  相似文献   
916.
Controlling the prevalence of Escherichia coli O157 in cattle at the pre-harvest level is critical to reduce outbreaks of this pathogen in humans. Multilayers of factors including the environmental and bacterial factors modulate the colonization and persistence of E. coli O157 in cattle that serve as a reservoir of this pathogen. Here, we report animal factors contributing to the prevalence of E. coli O157 in cattle. We observe the lowest number of E. coli O157 in Brahman breed when compared with other crosses in an Angus-Brahman multibreed herd, and bulls excrete more E. coli O157 than steers in the pens where cattle were housed together. The presence of super-shedders, cattle excreting >105 CFU/rectal anal swab, increases the concentration of E. coli O157 in the pens; thereby super-shedders enhance transmission of this pathogen among cattle. Molecular subtyping analysis reveal only one subtype of E. coli O157 in the multibreed herd, indicating the variance in the levels of E. coli O157 in cattle is influenced by animal factors. Furthermore, strain tracking after relocation of the cattle to a commercial feedlot reveals farm-to-farm transmission of E. coli O157, likely via super-shedders. Our results reveal high risk factors in the prevalence of E. coli O157 in cattle whereby animal genetic and physiological factors influence whether this pathogen can persist in cattle at high concentration, providing insights to intervene this pathogen at the pre-harvest level.  相似文献   
917.
Invertebrates rely solely on the innate immune system for defense against pathogens and other stimuli. Fatty acid binding proteins (FABP), members of the lipid binding proteins superfamily, play a crucial role in fatty acid transport and lipid metabolism and are also involved in gene expression induced by fatty acids. In the vertebrate immune system, FABP is involved in inflammation regulated by fatty acids through its interaction with peroxidase proliferator activate receptors (PPARs). However, the immune functions of FABP in invertebrates are not well characterized. For this reason, we investigated the immune functionality of two fatty acid binding proteins, Es-FABP9 and Es-FABP10, following lipopolysaccharide (LPS) challenge in the Chinese mitten crab (Eriocheir sinensis). An obvious variation in the expression of Es-FABP9 and Es-FABP10 mRNA in E. sinensis was observed in hepatopancreas, gills, and hemocytes post-LPS challenge. Recombinant proteins rEs-FABP9 and rEs-FABP10 exhibited distinct bacterial binding activity and bacterial agglutination activity against Escherichia coli and Staphylococcus aureus. Furthermore, bacterial growth inhibition assays demonstrated that rEs-FABP9 responds positively to the growth inhibition of Vibrio parahaemolyticuss and S. aureus, while rEs-FABP10 responds positively to the growth inhibition of Aeromonas hydrophila and Bacillus subtilis. Coating of agarose beads with recombinant rEs-FABP9 and rEs-FABP10 dramatically enhanced encapsulation of the beads by crab hemocytes in vitro. In conclusion, the data presented here demonstrate the participation of these two lipid metabolism-related proteins in the innate immune system of E. sinensis.  相似文献   
918.
HIV-1 Tat is an important regulatory protein involved in AIDS pathogenesis. However, the immunoprofiles of anti-Tat responses remain unclear. We analysed the immunoprofiles of the anti-Tat antibody responses and the neutralizing activities. Out of 326 HIV-1-seropositive individuals, 12.9% were positive for anti-Tat antibodies. We found six different immunological profiles of anti-Tat antibody responses: full-potential response, combined response, N-specific response, C-specific response, full-length Tat-specific response and Tat-related response. These responses represent two types of anti-Tat responses: the major complete response and the alternative C-prone response. A Tat-neutralizing activity is significantly higher in anti-Tat-seropositive samples than anti-Tat-negative or healthy blood-donor samples, and significantly correlates with the anti-Tat reactivities. The data here could contribute to a better understanding of the significance of anti-Tat responses in preventing HIV pathogenesis and could be useful for designing more effective vaccines in the future.  相似文献   
919.
920.
The study of systems genetics is changing the way the genetic and molecular basis of phenotypic variation, such as disease susceptibility and drug response, is being analyzed. Moreover, systems genetics aids in the translation of insights from systems biology into genetics. The use of systems genetics enables greater attention to be focused on the potential impact of genetic perturbations on the molecular states of networks that in turn affects complex traits. In this study, we developed models to detect allele-specific perturbations on interactions, in which a genetic locus with alternative alleles exerted a differing influence on an interaction. We utilized the models to investigate the dynamic behavior of an integrated molecular network undergoing genetic perturbations in yeast. Our results revealed the complexity of regulatory relationships between genetic loci and networks, in which different genetic loci perturb specific network modules. In addition, significant within-module functional coherence was found. We then used the network perturbation model to elucidate the underlying molecular mechanisms of individual differences in response to 100 diverse small molecule drugs. As a result, we identified sub-networks in the integrated network that responded to variations in DNA associated with response to diverse compounds and were significantly enriched for known drug targets. Literature mining results provided strong independent evidence for the effectiveness of these genetic perturbing networks in the elucidation of small-molecule responses in yeast.  相似文献   
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