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91.
Bingbing Wei You Zhou Zhuoqun Xu Jun Ruan Huan Cheng Ming Zhu Qiang Hu Ke Jin Zhiqiang Yan Deqi Zhou Feng Xuan Hongyi Zhou Zhirong Wang Xing Huang Qiang Wang 《PloS one》2013,8(8)
Background
Glutathione S-transferase P1 (GSTP1) is thought to be involved in the detoxification of reactive carcinogen metabolites. Numerous epidemiological studies have evaluated the association of GSTP1 Ile105Val polymorphism with the risk of prostate cancer. However, the results remain inconclusive. To derive a more precise estimation, a meta-analysis was performed.Methodology/Principal Findings
A comprehensive search was conducted to identify the eligible studies. We used odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of the relationship. The overall association was not significant (Val/Val vs. Ile/Ile OR = 1.06, 95% CI = 0.90–1.25, P = 0.50; Val/Val vs. Val/Ile+Ile/Ile: OR = 1.07, 95% CI = 0.91–1.25, P = 0.44). In subgroup analyses by ethnicity and prostate cancer grade, the similar results were observed. However, in stratified analysis by clinical stage, we found a significant association with low-stage prostate cancer (Val/Val vs. Ile/Ile: OR = 2.70, 95% CI = 1.73–4.22, P<0.001; Val/Val vs. Val/Ile+Ile/Ile: OR = 2.14, 95% CI = 1.38–3.33, P = 0.001). Moreover, there was no statistically significant evidence of multiplicative interactions neither between the GSTP1 Ile105Val polymorphism and GSTM1, nor between smoking status and GSTP1 on prostate cancer risk.Conclusions
This meta-analysis showed that GSTP1 Ile105Val polymorphism might not be significantly associated with overall prostate cancer risk. Further stratified analyses showed a significant association with low-stage prostate cancer. 相似文献92.
Peng Zhou Weiyi Xu Xueling Peng Zhenhua Luo Qinghe Xing Xulin Chen Chengqian Hou Weihong Liang Jianwen Zhou Xiaoyan Wu Zhou Songyang Songshan Jiang 《PloS one》2013,8(7)
Animal microRNA (miRNA) target prediction is still a challenge, although many prediction programs have been exploited. MiRNAs exert their function through partially binding the messenger RNAs (mRNAs; likely at 3′ untranslated regions [3′UTRs]), which makes it possible to detect the miRNA-mRNA interactions in vitro by co-transfection of miRNA and a luciferase reporter gene containing the target mRNA fragment into mammalian cells under a dual-luciferase assay system. Here, we constructed a human miRNA expression library and used a dual-luciferase assay system to perform large-scale screens of interactions between miRNAs and the 3′UTRs of seven genes, which included more than 3,000 interactions with triplicate experiments for each interaction. The screening results showed that the 3′UTR of one gene can be targeted by multiple miRNAs. Among the prediction algorithms, a Bayesian phylogenetic miRNA target identification algorithm and a support vector machine (SVM) presented a relatively better performance (27% for EIMMo and 24.7% for miRDB) against the average precision (17.3%) of the nine prediction programs used here. Additionally, we noticed that a relatively high conservation level was shown at the miRNA 3′ end targeted regions, as well as the 5′ end (seed region) binding sites. 相似文献
93.
Yan-Ping Li Liao-Bin Dong Duo-Zhi Chen Hong-Mei Li Jin-Dong Zhong Fei Li Xing Liu Bei Wang Rong-Tao Li 《Phytochemistry letters》2013,6(2):281-285
(7S,8R,7′S)-9,7′,9′-Trihydroxy-3,4-methylenedioxy-3′-methoxy [7-O-4′,8-5′] neolignan (1) and (7S,8R,7′S)-9,9′-dihydroxy-3,4-methylenedioxy-3′,7′-dimethoxy [7-O-4′,8-5′] neolignan (2), two new natural dihydrobenzofuran-type neolignans, along with 9,9′-dihydroxy-3,4-methylenedioxy-3′-methoxy [7-O-4′,8-5′] neolignan (3) and (-)-machicendiol (4), were isolated from the whole plants of Breynia fruticosa. The structures of 1 and 2, including the absolute configurations, were determined by spectroscopic methods and circular dichroism (CD) techniques. The absolute configuration of 4 was confirmed by calculations of the OR spectrum, together with OR and ECD spectra of its p-bromobenzoate ester (4a). 相似文献
94.
Xiaoli Luo Jiahe Wu Yuanbao Li Zhirun Nan Xing Guo Yixue Wang Anhong Zhang Zhian Wang Guixian Xia Yingchuan Tian 《PloS one》2013,8(1)
In plants, CuZn superoxide dismutase (CuZnSOD, EC l.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11), and catalase (CAT, EC l.11.1.6) are important scavengers of reactive oxygen species (ROS) to protect the cell from damage. In the present study, we isolated three homologous genes (GhSOD1, GhAPX1, and GhCAT1) from Gossypium hirsutum. Overexpressing cassettes containing chimeric GhSOD1, GhAPX1, or GhCAT1 were introduced into cotton plants by Agrobacterium transformation, and overexpressed products of these genes were transported into the chloroplasts by transit peptide, as expected. The five types of transgenic cotton plants that overexpressed GhSOD1, GhAPX1, GhCAT1, GhSOD1 and GhAPX1 stack (SAT), and GhSOD1 and GhCAT1 stack (SCT) were developed. Analyses in the greenhouse showed that the transgenic plants had higher tolerance to methyl viologen (MV) and salinity than WT plants. Interestingly, SCT plants suffered no damage under stress conditions. Based on analyses of enzyme activities, electrolyte leakage, chlorophyll content, photochemical yield (Fv/Fm), and biomass accumulation under stresses, the SCT plants that simultaneously overexpressed GhSOD1 and GhCAT1 appeared to benefit from synergistic effects of two genes and exhibited the highest tolerance to MV and salt stress among the transgenic lines, while the SAT plants simultaneously overexpressing GhSOD1 and GhAPX1 did not. In addition, transgenic plants overexpressing antioxidant enzymes in their chloroplasts had higher tolerance to salt stress than those expressing the genes in their cytoplasms, although overall enzyme activities were almost the same. Therefore, the synergistic effects of GhSOD1 and GhCAT1 in chloroplasts provide a new strategy for enhancing stress tolerance to avoid yield loss. 相似文献
95.
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96.
Jie Xu Xing Wu Wei-hua Zhou An-wen Liu Jian-bing Wu Jin-yun Deng Cai-feng Yue Shao-bing Yang Jing Wang Zhong-yu Yuan Quentin Liu 《PloS one》2013,8(2)
Triple negative breast cancer (TNBC) acquires an unfavorable prognosis, emerging as a major challenge for the treatment of breast cancer. In the present study, 122 TNBC patients were subjected to analysis of Aurora-A (Aur-A) expression and survival prognosis. We found that Aur-A high expression was positively associated with initial clinical stage (P = 0.025), the proliferation marker Ki-67 (P = 0.001), and the recurrence rate of TNBC patients (P<0.001). In TNBC patients with Aur-A high expression, the risk of distant recurrence peaked at the first 3 years and declined rapidly thereafter, whereas patients with Aur-A low expression showed a relatively constant risk of recurrence during the entire follow-up period. Univariate and multivariate analysis showed that overexpression of Aur-A predicted poor overall survival (P = 0.002) and progression-free survival (P = 0.012) in TNBC. Furthermore, overexpression of Aur-A, associated with high Ki-67, predicted an inferior prognosis compared with low expression of both Aur-A and Ki-67. Importantly, we further found that Aur-A was overexpressed in TNBC cells, and inhibition of this kinase inhibited cell proliferation and prevented cell migration in TNBC. Our findings demonstrated that Aur-A was a potential therapeutic target for TNBC and inhibition of Aur-A kinase was a promising regimen for TNBC cancer therapy. 相似文献
97.
Background
Polyporus umbellatus is an important medicinal fungus distributed throughout most area of China. Its wide distribution may have resulted in substantial intraspecific genetic diversity for the fungus, potentially creating variation in its medical value. To date, we know little about the intraspecific genetic diversity of P. umbellatus.Methodology/Principal Findings
The objective of this research was to assess genetic differences of P. umbellatus from geographically diverse regions of China based on nrDNA ITS and 28S rRNA (LSU, large subunit) sequences. Significant sequence variations in the ITS and LSU sequences were detected. All sclerotial samples were clustered into four clades based on phylogenetic analysis of ITS, LSU and a combined data set of both regions. Heterogeneity of ITS and LSU sequences was detected in 5 and 7 samples respectively. All clone sequences clustered into the same clade except for one LSU clone sequences (from Henan province) which clustered into two clades (Clade I and Clade II). Significant genetic divergence in P. umbellatus was observed and the genetic diversification was greater among sclerotial samples from Shaanxi, Henan and Gansu provinces than among other provinces. Polymorphism of ITS and LSU sequences indicated that in China, P. umbellatus may spread from a center (Shaanxi, Henan and Gansu province) to other regions.Conclusions/Significance
We found sclerotial samples of P. umbellatus contained levels of intraspecific genetic diversity. These findings suggested that P. umbellatus populations in Shaanxi, Henan and Gansu are important resources of genetic diversity and should be conserved accordingly. 相似文献98.
Shaohong Cheng Chandrasekhar Kesavan Subburaman Mohan Xuezhong Qin Catrina M. Alarcon Jon Wergedal Weirong Xing 《PloS one》2013,8(7)
To test if ephrin B1 overexpression enhances bone mass, we generated transgenic mice overexpressing ephrin B1 under the control of a 3.6 kb rat collagen 1A1 promoter (Col3.6-Tgefnb1). Col3.6-Tgefnb1 mice express 6-, 12- and 14-fold greater levels of full-length ephrin B1 protein in bone marrow stromal cells, calvarial osteoblasts, and osteoclasts, respectively. The long bones of both genders of Col3.6-Tgefnb1 mice have increased trabecular bone volume, trabecular number, and trabecular thickness and decreased trabecular separation. Enhanced bone formation and decreased bone resorption contributed to this increase in trabecular bone mass in Col3.6-Tgefnb1 mice. Consistent with these findings, our in vitro studies showed that overexpression of ephrin B1 increased osteoblast differentiation and mineralization, osterix and collagen 1A1 expression in bone marrow stromal cells. Interaction of ephrin B1 with soluble clustered EphB2-Fc decreased osteoclast precursor differentiation into multinucleated cells. Furthermore, we demonstrated that the mechanical loading-induced increase in EphB2 expression and newly formed bone were significantly greater in the Col3.6-Tgefnb1 mice than in WT littermate controls. Our findings that overexpression of ephrin B1 in bone cells enhances bone mass and promotes a skeletal anabolic response to mechanical loading suggest that manipulation of ephrin B1 actions in bone may provide a means to sensitize the skeleton to mechanical strain to stimulate new bone formation. 相似文献
99.
Liang Zhao Ya Xing Wang Wei Zhang Jing Shang Zhang Chang Xi Chen Liang Xu Jost B. Jonas 《PloS one》2013,8(7)
Objective
To assess the prevalence of localized retinal nerve fiber layer defects (LRNFLD) and associated factors in adult Chinese.Methods
The population-based Beijing Eye Study 2011 included 3468 individuals (mean age: 64.6±9.8 years (range: 50–93 years)). The study participants underwent a detailed ophthalmological examination including spectral-domain optical coherence tomography (SpectralisR-OCT) assisted measurement of the RNFL. A LRNFLD was defined as a sector in which the RNFL contour line dipped into the red zone for a length of <180°.Results
Readable OCT images were available for 3242 (93.5%) subjects. LRNFLDs were detected in 640 eyes (9.9±0.4%) of 479 subjects (14.8±0.6%). In the age groups of 50–59 years, 60–69 years, 70–79 years, and 80+ years, the prevalence of LRNFLD per person increased from 9.9±0.9%, 11.6±1.0% and 20.6±1.4% to 33.0±3.2%, respectively. In multivariate analysis, prevalence of LRNFLDs was significantly associated with older age (P = 0.001; Odds Ratio (OR): 1.03; 95% Confidence Interval (CI): 1.01,1.05), myopic refractive error (P<0.001;OR:0.79;95%CI:0.74,0.85), larger beta zone of parapapillary atrophy (P<0.001; OR:1.34;95%CI:1.20,1.50), presence of glaucomatous optic neuropathy (P<0.001;OR:7.02;95%CI:3.87,12.7), presence of non-glaucomatous optic nerve damage (P = 0.001;OR:43.3;95%CI:8.24,227.1), and presence of diabetic retinopathy (P = 0.003;OR:2.79;95%CI:1.43,5.44).Conclusions
OCT-defined LRNFLDs were present in a prevalence of 14.8±0.6% in a population-based study sample of subjects aged 50+ years. Prevalence of LRNFLDs increased with higher age, myopic refractive error, and larger parapapillary beta zone. Major ocular diseases associated with LRNFLs were glaucoma, non-glaucomatous optic nerve damage and diabetic retinopathy. These data may be helpful for a semiautomatic assessment of the RNFL. 相似文献100.
Yeqiang Liu Cheng Jin Aijun Xing Xiurong Liu Shuohua Chen Dongqing Li Ping Feng Jinquan Liu Zhiguo Li Shouling Wu 《PloS one》2013,8(12)