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91.
Probiotic therapies are going to be an effective alternative therapeutic strategy in the treatment and management of diabetes. The mechanism behind the essential effects of probiotic therapies in diabetic patients was not fully understood. The objective of this study was to evaluate the effects of probiotic soy milk containing Lactobacillus planetarum A7 on inflammation, lipid profile, fasting blood glucose, and serum adiponectin among patients with type 2 diabetes mellitus. Forty patients with type 2 diabetes, at the age of 35–68 years old, were assigned to two groups in this randomized, double-blind, controlled clinical trial. The patients in the intervention group consumed 200 ml/day of probiotic soy milk containing L. planetarum A7 and those in control group consumed 200 ml/day of pure soy milk for 8 weeks. Serum TNF-α, C reactive protein, adiponectin, lipid profile, and fasting blood glucose were determined before and after intervention. In intervention group, serum adiponectin in pre- and post-treatment did not show any significant changes (2.52 ± 0.74 vs 2.84 ± 0.61, P = 0.658), as well as changes in serum TNF-α and C reactive protein (172.44 ± 5.7 vs 172.83 ± 7.6, P = 0.278, 4.2 ± 1.4 vs 4.5 ± 1.9, P = 0.765, respectively). Low-density cholesterol and high-density cholesterol changed significantly (P = 0.023, P = 0.017, respectively), but fasting blood glucose did not show any significant changes. The results of this study showed that consumption of probiotic soy milk and soy milk has no effect on serum adiponectin and inflammation, but it can change lipid profile among type 2 diabetic patients.  相似文献   
92.
Populations in upstream versus downstream river locations can be exposed to vastly different environmental and ecological conditions and can thus harbor different genetic resources due to selection and neutral processes. An interesting question is how upstream–downstream directionality in rivers affects the evolution of immune response genes. We used next‐generation amplicon sequencing to identify eight alleles of the major histocompatibility complex (MHC) class II β exon 2 in the cyprinid longnose dace (Rhinichthys cataractae) from three rivers in Alberta, upstream and downstream of municipal and agricultural areas along contaminant gradients. We used these data to test for directional and balancing selection on the MHC. We also genotyped microsatellite loci to examine neutral population processes in this system. We found evidence for balancing selection on the MHC in the form of increased nonsynonymous variation relative to neutral expectations, and selection occurred at more amino acid residues upstream than downstream in two rivers. We found this pattern despite no population structure or isolation by distance, based on microsatellite data, at these sites. Overall, our results suggest that MHC evolution is driven by upstream–downstream directionality in fish inhabiting this system.  相似文献   
93.

Background  

Previous studies showed the ability of Pseudomonas putida strain BTP1 to promote induced systemic resistance (ISR) in different host plants. Since ISR is long-lasting and not conducive for development of resistance of the targeted pathogen, this phenomenon can take part of disease control strategies. However, in spite of the numerous examples of ISR induced by PGPR in plants, only a few biochemical studies have associated the protective effect with specific host metabolic changes.  相似文献   
94.
95.
A conceptual model is being developed for the prediction of cesium partitioning between bound, aqueous, and phytoextracted phases in the rhizosphere. The model categorizes the processes that impact cesium partitioning into six submodels: geochemistry, physical factors, root density, microorganisms, nutrients, and root exudates. A seventh submodel (Cs fate) describes Cs movement between the three phases. Functional relationships and parametric values within and between the submodels are developed based on literature, field characterization, and laboratory experiments. Sensitivity analyses were first conducted to evaluate the effects of root exudates on Cs partitioning. The model was also used to test the sensitivity of root density, microbial population, potassium requirement and concentration, and moisture content on the concentration of root exudates and consequently on Cs partitioning. An increase in the concentration of root exudates results in a greater decrease in the bound concentration and greater increase in the aqueous and phytoextracted concentrations. In general, the other parameters affect Cs partitioning according to how they affect the fate of root exudates. However, the comprehensive nature of the system renders a complex overall effect on Cs partitioning. In summary, the model provides a framework for better understanding the complex interaction of processes that control Cs fate in the rhizosphere.  相似文献   
96.
Biomolecule-centered radicals are intermediate species produced during both reversible (redox modulation) and irreversible (oxidative stress) oxidative modification of biomolecules. These oxidative processes must be studied in situ and in real time to understand the molecular mechanism of cell adaptation or death in response to changes in the extracellular environment. In this regard, we have developed and validated immuno-spin trapping to tag the redox process, tracing the oxidatively generated modification of biomolecules, in situ and in real time, by detecting protein- and DNA-centered radicals. The purpose of this methods article is to introduce and update the basic methods and applications of immuno-spin trapping for the study of redox biochemistry in oxidative stress and redox regulation. We describe in detail the production, detection, and location of protein and DNA radicals in biochemical systems, cells, and tissues, and in the whole animal as well, by using immuno-spin trapping with the nitrone spin trap 5,5-dimethyl-1-pyrroline N-oxide.  相似文献   
97.
Homoiologies are homoplasies that are caused by nongenetic environmental factors. The homoiology hypothesis predicts that osseous regions subject to repeated biomechanical stress during growth should be more variable and, therefore, less reliable for the reconstruction of phylogeny compared with osseous regions relatively unaffected by stress. Previous studies based on the analysis of multiple primate species found that regions of the cranium subject to masticatory-induced stress were significantly more variable than non-masticatory regions, as predicted by the homoiology hypothesis. However, these studies also found that the masticatory regions were no less reliable for reconstructing primate phylogenetic relationships when subjected to parsimony analysis. It was suggested, therefore, that homoiology may be a more potent problem for the reconstruction of phylogeny at the intraspecific level rather than interspecific phylogenetics. This suggestion was tested here using matched molecular and craniometric data for 12 modern human populations. The results show that, as predicted by the homoiology hypothesis, regions of the human cranium related to mastication were more variable than non-masticatory regions. However, masticatory regions were no less reliable for inferring human population history. Therefore, the results match those found from the interspecific analysis of primate species and do not support the suggestion that homoiology is a greater problem for the analysis of intraspecific taxa. The results also suggest that within-taxon variability cannot be relied upon to predict the phylogenetic efficacy of morphometric characters.  相似文献   
98.
Escherichia coli pseudouridine synthase RluF is dedicated to modifying U2604 in a stem-loop of 23S RNA, while a homologue, RluB, modifies the adjacent base, U2605. Both uridines are in the same RNA stem, separated by ∼ 4 Å. The 3.0 Å X-ray crystal structure of RluF bound to the isolated stem-loop, in which U2604 is substituted by 5-fluorouridine to prevent catalytic turnover, shows RluF distinguishes closely spaced bases in similar environments by a selectivity mechanism based on a frameshift in base pairing. The RNA stem-loop is bound to a conserved binding groove in the catalytic domain. A base from a bulge in the stem, A2602, has folded into the stem, forcing one strand of the RNA stem to translate by one position and thus positioning U2604 to flip into the active site. RluF does not modify U2604 in mutant stem-loops that lack the A2602 bulge and shows dramatically higher activity for a stem-loop with a mutation designed to facilitate A2602 refolding into the stem with concomitant RNA strand translation. Residues whose side chains contact rearranged bases in the bound stem-loop, while conserved among RluFs, are not conserved between RluFs and RluBs, suggesting that RluB does not bind to the rearranged stem loop.  相似文献   
99.

Background

The spread of agriculture into Europe and the ancestry of the first European farmers have been subjects of debate and controversy among geneticists, archaeologists, linguists and anthropologists. Debates have centred on the extent to which the transition was associated with the active migration of people as opposed to the diffusion of cultural practices. Recent studies have shown that patterns of human cranial shape variation can be employed as a reliable proxy for the neutral genetic relationships of human populations.

Methodology/Principal Findings

Here, we employ measurements of Mesolithic (hunter-gatherers) and Neolithic (farmers) crania from Southwest Asia and Europe to test several alternative population dispersal and hunter-farmer gene-flow models. We base our alternative hypothetical models on a null evolutionary model of isolation-by-geographic and temporal distance. Partial Mantel tests were used to assess the congruence between craniometric distance and each of the geographic model matrices, while controlling for temporal distance. Our results demonstrate that the craniometric data fit a model of continuous dispersal of people (and their genes) from Southwest Asia to Europe significantly better than a null model of cultural diffusion.

Conclusions/Significance

Therefore, this study does not support the assertion that farming in Europe solely involved the adoption of technologies and ideas from Southwest Asia by indigenous Mesolithic hunter-gatherers. Moreover, the results highlight the utility of craniometric data for assessing patterns of past population dispersal and gene flow.  相似文献   
100.
We previously identified two Trypanosoma brucei RNA binding proteins, P34 and P37, and determined that they are essential for proper ribosomal assembly in this organism. Loss of these proteins via RNA interference is lethal and causes a decrease in both 5S rRNA levels and formation of 80S ribosomes, concomitant with a decrease in total cellular protein synthesis. These data suggest that these proteins are involved at some point in the ribosomal biogenesis pathway. In the current study, we have performed subcellular fractionation in conjunction with immune capture experiments specific for 60S ribosomal proteins and accessory factors in order to determine when and where P34 and P37 are involved in the ribosomal biogenesis pathway. These studies demonstrate that P34 and P37 associate with the 60S ribosomal subunit at the stage of the nucleolar 90S particle and remain associated subsequent to nuclear export. In addition, P34 and P37 associate with conserved 60S ribosomal subunit nuclear export factors exportin 1 and Nmd3, suggesting that they are components of the 60S ribosomal subunit nuclear export complex in T. brucei. Most significantly, the pre-60S complex does not associate with exportin 1 or Nmd3 in the absence of P34 and P37. These results demonstrate that, although T. brucei 60S ribosomal subunits utilize a nuclear export complex similar to that described for other organisms, trypanosome-specific factors are essential to the process.  相似文献   
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