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81.

Background

The current study evaluated the association between tea consumption and head and neck cancer (HNC) in Taiwan, where tea is a major agricultural product and a popular beverage.

Methods

Interviews regarding tea consumption (frequency, duration, and types) were conducted with 396 HNC cases and 413 controls. Unconditional logistic regression was performed to estimate the odds ratio (OR) and 95% confidence interval (CI) of HNC risk associated with tea drinking, adjusted for sex, age, education, cigarette smoking, betel quid chewing, and alcohol drinking.

Results

A reduced HNC risk associated with tea drinking (OR for every cup per day = 0.96, 95% CI: 0.93–0.99; OR for ≧5 cups per day = 0.60, 95% CI: 0.39–0.94) was observed. The association was especially significant for pharyngeal cancer (OR for every cup per day = 0.93, 95% CI: 0.88–0.98; OR for ≧5 cups per day = 0.32, 95% CI: 0.16–0.66). A significant inverse association between HNC and tea consumption was observed particularly for green tea.

Conclusions

This study suggests that tea drinking may reduce the risk of HNC. The anticancer property of tea, if proven, may offer a natural chemopreventive measure to reduce the occurrence of HNC.  相似文献   
82.

Background

Contribution of cardiovascular disease related genetic risk factors for stroke are not clearly defined. We performed a genetic association study to assess the association of 56 previously characterized gene variants in 34 candidate genes from cardiovascular disease related biological pathways with ischemic stroke and cerebral hemorrhage in a Chinese population.

Methods

There were 1280 stroke patients (1101 with ischemic stroke and 179 with cerebral hemorrhage) and 1380 controls in the study. The genotypes for 56 polymorphisms of 34 candidate genes were determined by the immobilized probe approach and the associations of gene polymorphisms with ischemic stroke and cerebral hemorrhage were performed by logistic regression under an allelic model.

Results

After adjusting for age, sex, BMI and hypertension status by logistic regression analysis, we found that NPPA rs5063 was significantly associated with both ischemic stroke (odds ratio [OR] 0.69; 95% confidence interval [CI], 0.52 to 0.90; P = 0.006) and cerebral hemorrhage(OR = 0.39; 95%CI, 0.19 to 0.78; P = 0.007). In addition, MTHFR rs1801133 also was associated with cerebral hemorrhage (OR = 1.48; 95%CI, 1.16 to1.89; P = 0.001) but not with ischemic stroke (OR = 1.08; 95%CI, 0.96 to1.22; P = 0.210). After false discovery rate (FDR) correction, the association of NPPA rs5063 and MTHFR rs1801133 with cerebral hemorrhage remained significant.

Conclusions

The NPPA rs5063 is associated with reduced risk for cerebral hemorrhage and MTHFR rs1801133 is associated with increased risk of cerebral hemorrhage in a Chinese population.  相似文献   
83.
目的:研究在不同采收期、栽培环境、抽薹前后和组织部位的白花前胡甲素和乙素含量的变化规律.方法:采用高效液相色谱法测定不同采收时期栽培白花前胡甲素及乙素含量.结果:前胡甲素及乙素含量累积规律是根>茎>叶;二年生前胡甲素含量显著高于一年生,南坡前胡甲素显著高于其他坡向;抽薹前后的前胡甲素和乙素含量无显著差异.结论:高效液相...  相似文献   
84.
Raw leachate was treated using a two-stage upflow anaerobic filter process. Leachate from a solid waste landfill site, which received both municipal and industrial wastes, contained high organic matter (17-21 g/L COD, 13-14 g/L BOD, and 3.5-4.6 g/L volatile acids), and low metal (Zn and Fe) concentrations. Depending on sampling time, leachate composition and characteristics varied considerably. At an organic loading up to 4 g COD/day(2) media area, the BOD and COD removal percentages were 98 and 91%, respectively. The biofilters were also effective for metal removal. However, the filter effluent contained a high concentration of ammonia. System overloading was characterized by the accumulation of large quantities of volatile acids and by a now ratio of alkalinity/volatile acids, resulting in low COD removal and reduced gas production. Once the first filter was upset, the second stage could only partially respond to the volatile acids accumulated in the effluent of first filter.  相似文献   
85.
In order to explore the associations between trace elements in dietary intake and the other three biological media (blood, urine, or feces) and inter-element interactions among the latter, we simultaneously collected 72-h diet duplicates, whole blood, and 72-h urine and feces from 120 free-living healthy males in China. Correlations among the toxic (cadmium [Cd], lead [Pb]), and nutritionally essential (zinc [Zn], copper [Cu], iron [Fe], manganese [Mn], selenium [Se], iodine [I]) elements were evaluated using Spearman rank correlation analysis based on analytical data determined by inductively coupled plasma-mass spectrometry. Dietary Cd intakes were highly correlated with the fecal Cd and blood Cd levels. Inverse correlations were found for Fe–Cd and Fe–Pb in both diet versus blood and diet versus feces. Cd–Zn and Cd–Se were significantly directly correlated in the urine and feces. Cd–Se and Pb–Se were negatively correlated in blood. In addition, there existed an extremely significant association between urinary Se and urinary I. Moreover, the other two highly direct correlations were found for Se–Fe and for I–Fe in urine. Improved knowledge regarding their mutual associations is considered to be of fundamental importance to understand more the complex interrelationships in trace element metabolism.  相似文献   
86.
Isochrysis galbana, a marine prymnesiophyte microalga, is able to produce a high level of long chain polyunsaturated fatty acids such as docosahexaenoic acid (DHA, C22:6n-3). In this article, a novel gene (IgASE2) that encoded a C18-Δ9 polyunsaturase fatty acids specific (C18-Δ9-PUFAs-specific) elongase was isolated and characterized from DHA-rich microalga, I. galbana H29. A full-length cDNA of 1653 bp was cloned by rapidamplification of cDNA ends (RACE) PCR techniques. The IgASE2 contained a 786 bp ORF encoding a protein of 261 amino acids that shared 87% identity with the reported Δ9-elongase IgASE1, a 44 bp 5′ untranslated region and an 823 bp 3′ untranslated region. The function of IgASE2 was demonstrated by its heterologous expression in Saccharomyces cerevisiae. In S. cerevisiae, IgASE2 elongated linoleic acid (LA, C18:2n-6), α-linolenic (ALA, C18:3n-3) to eicosadienoic acid (EDA, C20:2n-6) and eicosatrienoic acid (ETrA, C20:3n-3). The conversion ratios of LA to EDA and ALA to ETrA were 60.47 and 58.36%, respectively. However, IgASE2 could not catalyze the elongation reactions of oleic acid (OA, C18:1n-9) and other fatty acids. These results confirmed that IgASE2 had C18-Δ9-PUFAs-specific elongase activity.  相似文献   
87.
The incidence of melanoma is rising globally including China. Comparing to Caucasians, the incidence of non‐cutaneous melanomas is significantly higher in Chinese. Herein, we performed genomic profiling of 89 Chinese surgically resected primary melanomas, including acral (n = 54), cutaneous (n = 22), and mucosal (n = 13), by hybrid capture‐based next‐generation sequencing. We show that mucosal melanomas tended to harbor more pathogenic mutations than other types of melanoma, though the biological significance of this finding remains uncertain. Chromosomal arm‐level alterations including 6q, 9p, and 10p/q loss were highly recurrent in all subtypes, but mucosal melanoma was significantly associated with increased genomic instability. Importantly, 7p gain significantly correlated with unfavorable clinical outcomes in non‐cutaneous melanomas, representing an intriguing prognostic biomarker of those subtypes. Furthermore, focal amplification of 4q12 (KIT, KDR, and PDGFRα) and RAD51 deletion were more abundant in mucosal melanoma, while NOTCH2 amplification was enriched in acral melanoma. Additionally, cutaneous melanomas had higher mutation load than acral melanomas, while mucosal melanomas did not differ from other subtypes in mutation burden. Together, our data revealed important features of acral and mucosal melanomas in Chinese including distinctive driver mutation pattern and increased genomic instability. These findings highlight the possibilities of combination therapies in the clinical management of melanoma.  相似文献   
88.
This investigation was intended to elucidate whether long noncoding RNA (lncRNA)-activated by transforming growth factor-β (ATB) interacting with miR-200c could mediate colorectal cancer (CRC) progression, offering potential strategies for diagnosing and treating CRC. Here totally 315 patients with CRC were recruited, and their CRC tissues and adjacent normal tissues were gathered. Concurrently, four colon cancer cell lines (ie, SW620, Lovo, HCT116, and SW480) and the human colon mucosal epithelial cell line (NCM460) were also purchased. Moreover, si-ATB, si-NC, miR-200c mimic, miR-200c inhibitor, and miR-NC were prepared for transfection into the CRC cells, and their effects on CRC cell lines were evaluated based on the conduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony formation assay, and flow cytometry assay. Eventually, the Luciferase reporter gene assay was carried out to judge if there existed a targeted relationship between ATB and miR-200c. The results of Cox regression analyses suggested that overexpressed lncRNA ATB, underexpressed miR-200c, poor tumor differentiation, lymph-vascular invasion, and perineural invasion were symbolic of shortened survival of the patients with CRC (all P < .05). Besides, transfection of pcDNA3.1-ATB and miR-200c inhibitor could boost the viability and proliferation of Lovo and SW620 cell lines (all P < .05). Meanwhile, the expressions of p53 and p21 were also reduced under treatments of pcDNA3.1-ATB and miR-200c inhibitor (P < .05). In addition, CDK2 seemed to reverse the contribution of miR-200c to intensifying viability and proliferation of Lovo and SW420 cell lines (P < .05). Furthermore, ATB might downregulate miR-200c expression by targeting it (P < .05), and CDK2 was subjected to dual regulation of both ATB and miR-200c (P < .05). In conclusion, the lncRNA ATB/miR-200c/CDK2 signaling was responsible for intensified proliferation and prohibited apoptosis of CRC cells, which might provide effective approaches for diagnosing and treating CRC.  相似文献   
89.
Di Cui  Shuching Ou  Sandeep Patel 《Proteins》2014,82(12):3312-3326
Hydrophobic effects, often conflated with hydrophobic forces, are implicated as major determinants in biological association and self‐assembly processes. Protein–protein interactions involved in signaling pathways in living systems are a prime example where hydrophobic effects have profound implications. In the context of protein–protein interactions, a priori knowledge of relevant binding interfaces (i.e., clusters of residues involved directly with binding interactions) is difficult. In the case of hydrophobically mediated interactions, use of hydropathy‐based methods relying on single residue hydrophobicity properties are routinely and widely used to predict propensities for such residues to be present in hydrophobic interfaces. However, recent studies suggest that consideration of hydrophobicity for single residues on a protein surface require accounting of the local environment dictated by neighboring residues and local water. In this study, we use a method derived from percolation theory to evaluate spanning water networks in the first hydration shells of a series of small proteins. We use residue‐based water density and single‐linkage clustering methods to predict hydrophobic regions of proteins; these regions are putatively involved in binding interactions. We find that this simple method is able to predict with sufficient accuracy and coverage the binding interface residues of a series of proteins. The approach is competitive with automated servers. The results of this study highlight the importance of accounting of local environment in determining the hydrophobic nature of individual residues on protein surfaces. Proteins 2014; 82:3312–3326. © 2014 Wiley Periodicals, Inc.  相似文献   
90.
Though people had recognized the pivotal function of CaCl(2) during DNA transformation into Escherichia coli, the mechanism of divalent Ca(2+) cation inducing E. coli competence development is still unknowable. Quantum dots (QDs), as a new fluorescent probe, being applied in biology research, had aroused great interest. We explored the penetrability of E. coli competent cells membrane using QDs and proved directly that competent cells were more permeable than that of noncompetent. The results are significant on understanding the problems of the microbiological genetics.  相似文献   
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