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101.
BackgroundSeveral original studies have investigated the effect of alcohol use disorder (AUD) on suicidal thought and behavior, but there are serious discrepancies across the studies. Thus, a systematic assessment of the association between AUD and suicide is required.MethodsWe searched PubMed, Web of Science, and Scopus until February 2015. We also searched the Psycinfo web site and journals and contacted authors. We included observational (cohort, case-control, and cross-sectional) studies addressing the association between AUD and suicide. The exposure of interest was AUD. The primary outcomes were suicidal ideation, suicide attempt, and completed suicide. We assessed heterogeneity using Q-test and I2 statistic. We explored publication bias using the Egger''s and Begg''s tests and funnel plot. We meta-analyzed the data with the random-effects models. For each outcome we calculated the overall odds ratio (OR) or risk ratio (RR) with 95% confidence intervals (CI).ResultsWe included 31 out of 8548 retrieved studies, with 420,732 participants. There was a significant association between AUD and suicidal ideation (OR=1.86; 95% CI: 1.38, 2.35), suicide attempt (OR=3.13; 95% CI: 2.45, 3.81); and completed suicide (OR=2.59; 95% CI: 1.95, 3.23 and RR=1.74; 95% CI: 1.26, 2.21). There was a significant heterogeneity among the studies, but little concern to the presence of publication bias.ConclusionsThere is sufficient evidence that AUD significantly increases the risk of suicidal ideation, suicide attempt, and completed suicide. Therefore, AUD can be considered an important predictor of suicide and a great source of premature death.  相似文献   
102.
Molecular Biology Reports - Microalgae and cyanobacteria are the potentially valuable source of bioactive compounds applied in the various industries and human usage in different fields of...  相似文献   
103.
International Journal of Peptide Research and Therapeutics - Antimicrobial peptides (AMPs) are a crucial part of innate immunity that exist in the most of living organisms. In fact, AMPs have...  相似文献   
104.
The width of the DNA minor groove varies with sequence and can be a major determinant of DNA shape recognition by proteins. For example, the minor groove within the center of the Fis–DNA complex narrows to about half the mean minor groove width of canonical B-form DNA to fit onto the protein surface. G/C base pairs within this segment, which is not contacted by the Fis protein, reduce binding affinities up to 2000-fold over A/T-rich sequences. We show here through multiple X-ray structures and binding properties of Fis–DNA complexes containing base analogs that the 2-amino group on guanine is the primary molecular determinant controlling minor groove widths. Molecular dynamics simulations of free-DNA targets with canonical and modified bases further demonstrate that sequence-dependent narrowing of minor groove widths is modulated almost entirely by the presence of purine 2-amino groups. We also provide evidence that protein-mediated phosphate neutralization facilitates minor groove compression and is particularly important for binding to non-optimally shaped DNA duplexes.  相似文献   
105.
Isolates of the most important Puccinia species that have been reported on Chrysanthemum × morifolium were collected and the sequences of their ribosomal DNA internal transcribed spacers ITS1 and ITS2 were determined and used as phylogenetic markers. The focus of this study was on Puccinia horiana, due to its quarantine status and its impact in commercial chrysanthemum production. Three technical adjustments were needed to reliably obtain the nucleotide sequences starting from fresh or dried samples. The complete rDNA ITS nucleotide sequences of P. horiana, Puccinia chrysanthemi, and Puccinia tanaceti isolates of varying age and geographic origin were determined. We also identified an as yet undescribed Puccinia species on six old herbarium samples from chrysanthemum. This new species is morphologically similar to P. chrysanthemi and near identical to recent rust samples from Artemisia tridentata. P. tanaceti could not be confirmed as a pathogen of chrysanthemum. Different rDNA ITS sequences were present in P. horiana, with intra-isolate and inter-isolate variability in the length of three nucleotide repeat regions in the different rDNA tandem copies. We also identified three ITS types within P. horiana, with the rarer types displaying up to 67 bp nucleotide sequence differences. These rarer ITS types were detected at low copy number in all isolates. In general, very little rDNA ITS sequence variation was observed between P. horiana isolates from 1903 and 2003, and among isolates from different continents. Phylogenetic analyses using distance, Maximum Likelihood and Bayesian methods confirmed P. horiana, P. chrysanthemi, and the new Puccinia sp. as well-resolved groups, with P. horiana clustering in the clade where the economically important rust species of the Poaceae are located, and P. chrysanthemi and the new Puccinia sp. clustering in the clade where the majority of the rust fungi with hosts in the Asteraceae is located.  相似文献   
106.
This paper describes the use of a quantitative competitive polymerase chain reaction (QC-PCR) assay; using PCR primers to the rRNA locus of rumen fungi and a standard-control DNA including design and validation. In order to test the efficiency of this method for quantifying anaerobic rumen fungi, it has been attempted to evaluate this method in in vitro conditions by comparing with an assay based on measuring cell wall chitin. The changes in fungal growth have been studied when they are grown in in vitro on either untreated (US) or sodium hydroxide treated wheat straw (TS). Results showed that rumen fungi growth was significantly higher in treated samples compared with untreated during the 12 d incubation (P < 0.05) and plotting the chitin assay's results against the competitive PCR's showed high positive correlation (R2 ≥ 0.87). The low mean values of the coefficients of variance in repeatability in the QC-PCR method against the chitin assay demonstrated more reliability of this new approach. And finally, the efficiency of this method was investigated in in vivo conditions. Samples of rumen fluid were collected from four fistulated Holstein steers which were fed four different diets (basal diet, high starch, high sucrose and starch plus sucrose) in rotation. The results of QC-PCR showed that addition of these non-structural carbohydrates to the basal diets caused a significant decrease in rumen anaerobic fungi biomass. The QC-PCR method appears to be a reliable and can be used for rumen samples.  相似文献   
107.
Defect in cell cycle control is a hallmark character of cancer. We have investigated the association of Ki67 labeling index, cyclin E and CDC25A expressions with clinical follow-up data in breast carcinomas. Flow cytometry was used to detect gene amplification of cyclins in 44 tumor tissue with invasive breast carcinomas. Multivariate Cox proportional hazard ratio test was used to show the correlations. Cyclin E or CDC25A were upregulated in 34% of the tumors. Among the whole total material, expression of cyclin E and of CDC25A were found upregulated in 31.9% and 39.4% of cells, respectively. Both CDC25A and cyclin E protein expression levels were correlated with Ki67 expression level (p < 0.001). In addition, the expression of CDC25A was associated significantly with poor survival (P = 0.028), whereas no correlation was found with cyclin E. These findings suggest a possible prognostic value for CDC25A as a cell cycle marker and may imply in characteristic of high risk breast cancer patients.  相似文献   
108.
109.
In this study, hard shell of apricot stones was selected from agricultural solid wastes to prepare effective and low cost adsorbent for the gold separation from gold-plating wastewater. Different adsorption parameters like adsorbent dose, particle size of activated carbon, pH and agitation speed of mixing on the gold adsorption were studied. The results showed that under the optimum operating conditions, more than 98% of gold was adsorbed onto activated carbon after only 3 h. The equilibrium adsorption data were well described by the Freundlich and Langmuir isotherms. Isotherms have been used to obtain thermodynamic parameters. Gold desorption studies were performed with aqueous solution mixture of sodium hydroxide and organic solvents at ambient temperatures. Quantitative recovery of gold ions is possible by this method. As hard shell of apricot stones is a discarded as waste from agricultural and food industries, the prepared activated carbon is expected to be an economical product for gold ion recovery from wastewater.  相似文献   
110.
Probiotics are used as a treatment for different intestinal disorders. They confer health benefits by different ways. This study was aimed to investigate immunomodulatory effect of Bacillus probiotic spores on the production of lipopolysaccharide (LPS)-induced interleukin 8 (IL-8) in HT-29 intestinal epithelial cells. Differentiated intestinal epithelial cell line was used as a model for the study of colonization of purified spores (Bacillus subtilis (natto) and B. coagulans) and their anti-inflammatory effects. MTT assay and trypan blue staining were used for the detection of optimal concentration of the purified spores and LPS. Pre-treatment assay was done by treatment of the cells with the purified spores for 2 h, followed by challenges with LPS for 3 and 18 h. Post-treatment assay was done by initial treatment of the cells with LPS for 18 h, followed by the spores for 3 and 6 h. Levels of IL-8 secretion and its mRNA expression were measured by ELISA and relative Q real-time PCR. Our results showed similar rates of adherence to intestinal epithelial cells by the spore probiotics, while displaying no cytotoxic effect. In the pre-treatment assay, a significant decrease in IL-8, at both protein and mRNA levels, was measured for B. coagulans spores after the addition of LPS, which was higher than those observed for Bacillus subtilis (natto) spores. In the post-treatment assay, while Bacillus subtilis (but not B. coagulans) diminished the LPS-stimulated IL-8 levels after 3 h of incubation, the inhibitory effect was not constant. In conclusion, ability of Bacillus spore probiotics for adherence to intestinal epithelial cell and their anti-inflammatory effects, through interference with LPS/IL-8 signaling, was shown in this study. Further studies are needed to characterize responsible bacterial compounds associated with these effects.  相似文献   
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