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981.
982.
Hong-Hee Won Woojae Myung Gil-Young Song Won-Hee Lee Jong-Won Kim Bernard J. Carroll Doh Kwan Kim 《PloS one》2013,8(4)
Suicide is not only an individual phenomenon, but it is also influenced by social and environmental factors. With the high suicide rate and the abundance of social media data in South Korea, we have studied the potential of this new medium for predicting completed suicide at the population level. We tested two social media variables (suicide-related and dysphoria-related weblog entries) along with classical social, economic and meteorological variables as predictors of suicide over 3 years (2008 through 2010). Both social media variables were powerfully associated with suicide frequency. The suicide variable displayed high variability and was reactive to celebrity suicide events, while the dysphoria variable showed longer secular trends, with lower variability. We interpret these as reflections of social affect and social mood, respectively. In the final multivariate model, the two social media variables, especially the dysphoria variable, displaced two classical economic predictors – consumer price index and unemployment rate. The prediction model developed with the 2-year training data set (2008 through 2009) was validated in the data for 2010 and was robust in a sensitivity analysis controlling for celebrity suicide effects. These results indicate that social media data may be of value in national suicide forecasting and prevention. 相似文献
983.
Matthew B. Laurens Peter Billingsley Adam Richman Abraham G. Eappen Matthew Adams Tao Li Sumana Chakravarty Anusha Gunasekera Christopher G. Jacob B. Kim Lee Sim Robert Edelman Christopher V. Plowe Stephen L. Hoffman Kirsten E. Lyke 《PloS one》2013,8(7)
Controlled human malaria infection (CHMI) is a powerful method for assessing the efficacy of anti-malaria vaccines and drugs targeting pre-erythrocytic and erythrocytic stages of the parasite. CHMI has heretofore required the bites of 5 Plasmodium falciparum (Pf) sporozoite (SPZ)-infected mosquitoes to reliably induce Pf malaria. We reported that CHMI using the bites of 3 PfSPZ-infected mosquitoes reared aseptically in compliance with current good manufacturing practices (cGMP) was successful in 6 participants. Here, we report results from a subsequent CHMI study using 3 PfSPZ-infected mosquitoes reared aseptically to validate the initial clinical trial. We also compare results of safety, tolerability, and transmission dynamics in participants undergoing CHMI using 3 PfSPZ-infected mosquitoes reared aseptically to published studies of CHMI using 5 mosquitoes. Nineteen adults aged 18–40 years were bitten by 3 Anopheles stephensi mosquitoes infected with the chloroquine-sensitive NF54 strain of Pf. All 19 participants developed malaria (100%); 12 of 19 (63%) on Day 11. The mean pre-patent period was 258.3 hours (range 210.5–333.8). The geometric mean parasitemia at first diagnosis by microscopy was 9.5 parasites/µL (range 2–44). Quantitative polymerase chain reaction (qPCR) detected parasites an average of 79.8 hours (range 43.8–116.7) before microscopy. The mosquitoes had a geometric mean of 37,894 PfSPZ/mosquito (range 3,500–152,200). Exposure to the bites of 3 aseptically-raised, PfSPZ-infected mosquitoes is a safe, effective procedure for CHMI in malaria-naïve adults. The aseptic model should be considered as a new standard for CHMI trials in non-endemic areas. Microscopy is the gold standard used for the diagnosis of Pf malaria after CHMI, but qPCR identifies parasites earlier. If qPCR continues to be shown to be highly specific, and can be made to be practical, rapid, and standardized, it should be considered as an alternative for diagnosis.
Trial Registration
ClinicalTrials.gov NCT00744133 NCT00744133相似文献984.
985.
Background
Improving the health and well-being of women and children has long been a common goal throughout the world. From 2005 to 2011, Suizhou City had an annual average of 22,405 pregnant and parturient women (1.04% of the population) and 98,811 children under 5 years old (4.57% of the population). Understanding the status of maternal and child health care in Suizhou City during such period can provide the local health administrative department valid scientific bases upon which to construct effective policies.Methods
Various types of annual reports on maternal and child health care were collected and analyzed retrospectively.Results
Mortality rates for infants and children under 5 years showed a declining trend, while the rates of newborn home visiting, maternal health service coverage, and children health systematic management increased annually in Suizhou City from 2005 to 2011. The incidence of birth defect increased from 2.42‰ in 2005 to 3.89‰ in 2011. The maternal mortality ratio (MMR) fluctuated from 8.39/100,000 to 28.77/100,000, which was much lower than the national MMR (30.0/100,000 in 2010). The rates of hospitalized delivery and births attended by trained health personnel for pregnant women increased to more than 90% in the past five years.Conclusions
The improvements in maternal and child health care work in Suizhou City are worthy of recognition. Thus, the government should continue to increase funding in these areas to promote the complete enhancement of the maternal and child health care system. 相似文献986.
Background
Interleukin (IL)-13, a T-helper type 2 cytokine, plays a critical role in the development of chronic obstructive pulmonary disease (COPD). This meta-analysis was performed to assess the association of IL-13 −1112 C/T promoter polymorphism with COPD susceptibility.Methods
Published case-control studies from Pubmed and China National Knowledge Infrastructure (CNKI) databases were retrieved. Data were extracted and pooled odds ratios (OR) with 95% confidence intervals (CI) were calculated.Results
Eight case-control studies in seven articles were included in this meta-analysis. Pooled effect size showed IL-13 −1112 C/T was associated with COPD susceptibility in a codominant genetic model (TT vs CT, OR: 1.82, 95% CI: 1.14–2.92 and TT vs CC, OR: 2.02, 95% CI: 1.10–3.72), indicating individuals with TT genotype had an increased risk for COPD compared with those with CT or CC genotype. According to ethnicity, results indicated IL-13 −1112 C/T was correlated with COPD susceptibility in Arabians (TT vs CT, OR: 2.94, 95% CI: 1.03–8.42 and TT vs CC, OR: 3.05, 95% CI: 1.08–8.59). Moreover, after excluding the study without Hardy-Weinberg equilibrium, the pooled results were robust and no publication bias was found in this study.Conclusions
This meta-analysis suggests IL-13 −1112 C/T promoter polymorphism is associated with the risk of COPD in Arabians. 相似文献987.
Fujiao Duan Wei Xie Lihong Cui Peng Wang Chunhua Song Honghong Qu Kaijuan Wang Jianying Zhang Liping Dai 《Cancer epidemiology》2013,37(5):647-652
A novel functional single nucleotide polymorphism (SNP) rs2274223 located in the phospholipase C epsilon 1 (PLCE1) gene was found to be associated with the risk of esophageal squamous cell carcinoma (ESCC) by three large-scale genome-wide association studies (GWAS) in Chinese populations. In the present study, we validated this finding and also explored the risk of ESCC associated with other two unreported potentially functional SNPs (rs17417407 G > T and rs2274224 C > G) of PLCE1 in a population-based case–control study to investigate the association between these three potentially functional SNPs in PLCE1 and susceptibility to ESCC. A total of 381 ESCC cases and 420 controls matched by age and sex were recruited and successfully genotyped for three SNPs (rs17417407, rs2274223 and rs2274224) of the PLCE1 in a central Chinese population. SNP rs2274223 was independently associated with increased risk of ESCC (adjusted odds ratio [OR], 2.80; 95% confidence interval [95% CI], 1.45–5.39 for GG vs. AA), and SNP rs2274224 was found to be associated with decreased risk of ESCC (adjusted OR, 0.65; 95% CI, 0.46–0.91 for CG vs. CC). The combined effects of risk alleles for three SNPs (rs17417407T, rs2274223G and rs2274224G) were found to be associated with elevated risk of ESCC in a dose-dependent effect manner (Ptrend = 0.005). The Grs17417407Ars2274223Crs2274224 haplotype decreased the risk of ESCC (adjusted OR, 0.76; 95% CI, 0.62–0.93), meanwhile the Grs17417407Grs2274223Crs2274224 and Trs17417407Grs2274223Crs2274224 haplotypes could increase the risk of ESCC (adjusted OR, 1.75; 95% CI, 1.33–2.18 and OR, 2.51; 95% CI, 1.15–2.49). Gene–environment interaction analysis presented a best model consisted of four factors (rs2274223, rs2274224, family history, and smoking) with testing balance accuracy (TBA): 0.66 and cross validation consistency (CVC): 7/10, which could increase the esophageal cancer risk in the “high risk group” with 3.67-fold (OR: 3.67, 95% CI: 2.74–4.92), compared to the “low risk group”. Our results further confirmed that genetic variations in PLCE1 may contribute to ESCC risk associated with tobacco exposure in a central Chinese population. Further functional studies are needed to validate our results. 相似文献
988.
Zuoxu Fan Tao Ji Shu Wan Yaoyao Wu Yu Zhu Feng Xiao Renya Zhan 《Cancer epidemiology》2013,37(1):39-45
Objective: The relationship between smoking and the development of meningioma has been investigated in several epidemiological studies. However, the results of these studies are inconsistent. We conducted a meta-analysis in order to identify any potential association. Methods: PubMed, the Cochrane Library, and EMBASE databases were searched to identify relevant articles that investigated the risk of meningioma following cigarette smoking. Two researchers evaluated study eligibility and extracted the data independently, and disagreements were resolved by discussion. The variables used to estimate the pooled risk of smoking in meningioma development were the multivariate-adjusted risk estimates presented in the literature. Results: Seven case–control and two cohort studies were included in this meta-analysis. The pooled estimated risks associated with ever smoking for meningioma were 1.02 (95% confidence interval (CI): 0.85–1.21) in the case–control studies, 0.93 (95% CI: 0.83–1.04) in the cohort studies and 0.95 (95% CI: 0.87–1.05, P = 0.32) in all studies when the cohort and case–control data were combined. Subgroup analyses suggested that the risk estimates were 1.49 (95% CI: 1.06–2.09, P = 0.02), 0.86 (95% CI: 0.65–1.13), 0.79 (95% CI: 0.50–1.25) and 0.84 (95% CI: 0.69–1.03) for men, women, current and past smoking respectively. Sensitivity analyses restricted to studies with different adjustments for confounders yielded similar results. No evidence of publication bias was observed. Conclusion: Our meta-analysis suggests that there is no association between ever smoking and the risk of meningioma. However, a small but significant risk elevation is present among men smokers. 相似文献
989.
Yong-Mei Xing Li-Chun Zhang Han-Qiao Liang Jing Lv Chao Song Shun-Xing Guo Chun-Lan Wang Tae-Soo Lee Min-Woong Lee 《PloS one》2013,8(2)
Background
Polyporus umbellatus sclerotia have been used as a diuretic agent in China for over two thousand years. A shortage of the natural P. umbellatus has prompted researchers to induce sclerotial formation in the laboratory.Methodology/Principal Finding
P. umbellatus cultivation in a sawdust-based substrate was investigated to evaluate the effect of low temperature conditions on sclerotial formation. A phenol-sulfuric acid method was employed to determine the polysaccharide content of wild P. umbellatus sclerotia and mycelia and sclerotia grown in low-temperature treatments. In addition, reactive oxygen species (ROS) content, expressed as the fluorescence intensity of mycelia during sclerotial differentiation was determined. Analysis of ROS generation and sclerotial formation in mycelia after treatment with the antioxidants such as diphenyleneiodonium chloride (DPI), apocynin (Apo), or vitamin C were studied. Furthermore, macroscopic and microscopic characteristics of sclerotial differentiation were observed. Sclerotia were not induced by continuous cultivation at 25°C. The polysaccharide content of the artificial sclerotia is 78% of that of wild sclerotia. In the low-temperature treatment group, the fluorescent intensity of ROS was higher than that of the room temperature (25°C) group which did not induce sclerotial formation all through the cultivation. The antioxidants DPI and Apo reduced ROS levels and did not induce sclerotial formation. Although the concentration-dependent effects of vitamin C (5–15 mg mL−1) also reduced ROS generation and inhibited sclerotial formation, using a low concentration of vitamin C (1 mg mL−1) successfully induced sclerotial differentiation and increased ROS production.Conclusions/Significance
Exposure to low temperatures induced P. umbellatus sclerotial morphogenesis during cultivation. Low temperature treatment enhanced ROS in mycelia, which may be important in triggering sclerotial differentiation in P. umbellatus. Moreover, the application of antioxidants impaired ROS generation and inhibited sclerotial formation. Our findings may help to provide new insights into the biological mechanisms underlying sclerotial morphogenesis in P. umbellatus. 相似文献990.
Xianyu Zhang Qian Sun Ming Shan Ming Niu Tong Liu Bingshu Xia Xiaoshuan Liang Wei Wei Shanshan Sun Youxue Zhang Xiaolong Sean Liu Qingbin Song Yanmei Yang Yuyan Ma Yang Liu Long Yang Yanlv Ren Guoqiang Zhang Da Pang 《PloS one》2013,8(1)
ARID1A (AT-rich interactive domain 1A) has recently been identified as a tumor suppressor gene. Its mRNA expression is significantly low in many breast cancers; this is often associated with more aggressive phenotypes. However, the underlying molecular mechanism for its low expression has not been fully understood. This study was undertaken to evaluate the contribution of gene copy number variation, mutations, promoter methylation and histone modification to ARID1A’s low expression. 38 pairs of breast invasive ductal carcinomas and their normal breast tissue counterparts from the same patients were randomly selected for gene expression and copy number variation detection. Promoter methylation and histone modification levels were evaluated by MeDIP-qPCR and ChIP-qPCR, respectively. PCR product Sanger sequencing was carried out to detect the exon mutation rate. Twenty-two out of 38 invasive ductal carcinomas in the study (57.9%) revealed ARID1A mRNA low expression by realtime RT-PCR. The relative promoter methylation level was, significantly higher in ARID1A mRNA low expression group compared with its high expression group (p<0.001). In the low expression group, nineteen out of 22 invasive ductal carcinomas (86.4%) exhibited ARID1A promoter hypermthylation. In addition, the promoter hypermethylation was accompanied with repressive histone modification (H3K27Me3). Although five out of 38 invasive ductal carcinomas (13.2%) exhibited loss of ARID1A gene copy number by realtime PCR and nine exon novel mutations are seen from eight out of 33 invasive ductal carcinomas (24.2%), there was no statistically significant difference in both ARID1A mRNA low and high expression groups (p = 0.25,and p = 0.68, respectively). We demonstrate that promoter hypermethylation was the main culprit for ARID1A mRNA low expression in invasive ductal carcinomas. The influence of mutation and copy number variation on the expression were statistically insignificant at mRNA level, and were, therefore, not considered the main causes for ARID1A mRNA low expression in invasive breast cancer. 相似文献