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801.
Haijian Du Xiaorong Chen Yi Fang Ouyang Yan Hong Xu Li Li Weifeng Li Wenjie Huang 《Molecular biology reports》2013,40(5):3591-3596
Pathogenesis and genetic factors influencing predisposition to antituberculosis drug-induced hepatotoxicity (ATDH) are not clear. Polymorphism at the genetic locus of a drug and xenobiotic compound metabolizing enzyme, N-acetyltransferase type 2 (NAT2), is reported to be associated with the excess generation of toxic reactive metabolites. To date, many case–control studies have been carried out to investigate the relationship between the NAT2 polymorphisms and ATDH, but the results have been inconsistent. To investigate this inconsistency, a meta-analysis was performed. Databases including PubMed, Web of Science, EMBASE and CNKI were searched to find relevant studies. A total of 26 case–control studies, involving 1,198 cases and 2,921 controls were included. Overall, we found significant association between slow acetylator genotype of NAT2 and ATDH (OR = 3.10, 95 % CI: 2.47–3.88, P < 10?5). Significant results were also found in East Asians, South Asians, Brazilians and Middle Eastern when stratified by ethnicity. However, no significant associations were found for Caucasians. This meta-analysis demonstrated that the slow acetylator genotype of NAT2 is a risk factor associated with increased ATDH susceptibility, but these associations vary in different ethnic populations. 相似文献
802.
Background
Methionine synthase (MTR) and methionine synthase reductase (MTRR) genes have been considered to be implicated in the development of neural tube defects (NTDs). However, the results are inconsistent. Accordingly, we conducted a meta-analysis to further investigate such an association.Methods
Published literature from PubMed and Embase databases was retrieved. All studies evaluating the association between MTR A2756G or MTRR A66G polymorphism and maternal risk for NTDs were included. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated using the fixed- or random-effects model.Results
A total of 11 studies (1005 cases and 2098 controls) on MTR A2756G polymorphism and 10 studies (1211 cases and 2003 controls) on MTRR A66G polymorphism were included. Overall, this meta-analysis revealed no significant association between maternal MTR A2756G polymorphism and NTD susceptibility in either genetic model. A significant association between MTRR A66G polymorphism and maternal risk for NTDs was observed for GG vs. AA (OR = 1.31, 95% CI 1.03–1.67) among Caucasians.Conclusion
The present meta-analysis indicated that MTRR A66G polymorphism, but not MTR A2756G, is significantly associated with maternal risk for NTDs in Caucasians. 相似文献803.
Ultradian clock-coupled respiratory oscillation (UCRO) in an aerobic continuous culture of Saccharomyces cerevisiae S288C is principally regulated by control of certain redox reactions of energy metabolism. It is also modulated by the metabolism of storage carbohydrates during adaptation to environmental change. However, the mechanism of cell sensing and response to environmental nutrients in UCRO is unknown. The purpose of the present study was to determine the role of PSK2 kinase in UCRO in yeast. S. cerevisiae in culture showed oscillation in PSK2 mRNA levels with a definite phase relationship to the respiratory oscillation. Furthermore, inactivation of Psk2 by gene disruption severely affected UCRO and its decline to undetectable levels within 2 days. In addition, the extracellular and intracellular glucose concentrations of PSK2 deletion mutants in culture were higher and lower, respectively, than those of the wild type. PSK2 mutant cells showed no alteration in redox state. Furthermore, the levels of storage carbohydrates such as glycogen and trehalose fluctuated in PSK2 mutants with attenuated amplitudes comparable to those in the wild type. The results indicated that PSK2 kinase is important for the uptake of glucose and regulation of storage-carbohydrate synthesis and hence the maintenance of an unperturbed continuously oscillating state. 相似文献
804.
Tao Fan Shuo Yang Zhixin Huang Wei Wang Xiaobo Guo Shize Pan Boyou Zhang Yao Xu Yifan Fang Zhangfan Mao Hao Hu Qing Geng 《Journal of cellular physiology》2020,235(11):7982-7995
To research the impact of autophagy on alveolar epithelial cell inflammation and its possible mechanism in the early stages of hypoxia, we established a cell hypoxia–reoxygenation model and orthotopic left lung ischemia–reperfusion model. Rat alveolar epithelial cells stably expressing GFP-LC3 were treated with an autophagy inhibitor (3-MA) or an autophagy promoter (rapamycin), followed by hypoxia–reoxygenation treatment for 2, 4, and 6 hr in vitro. In vivo, 20 male Sprague Dawley rats were randomly divided into four groups (model group: No blocking of the hilum in the left lung; control group: Blocking of the hilum in the left lung for 1 hr with dimethyl sulfoxide lavage; 3-MA group: Blocking of the hilum in the left lung for 1 hr with 100 ml/kg of 3-MA (5 μmol/L) solution lavage; and rapamycin group: Blocking of the hilum in the left lung for 1 hr with 100 ml/kg of rapamycin (250 nmol/L) solution lavage) to establish an orthotopic left lung ischemia model. This study demonstrated that rapamycin significantly suppressed the nuclear factor kappa B signaling pathway and limited the expression of proinflammatory factors. A contrary result was found after the 3-MA pretreatment. These findings indicate that autophagy reduces ischemia–reperfusion injury by repressing inflammatory signaling pathways in the early stages of hypoxia in vitro and in vivo. Autophagy could be a new protective method for application in lung ischemia–reperfusion injury. 相似文献
805.
尾叶樱桃(Cerasus dielsiana(Schneid.)Yu et Li)特产于中国亚热带山区,是一种集观赏、食用、药用、材用和生态防护等多用途为一体的代表性野生樱属植物,具有广阔的开发利用前景。本文全面系统地概述了其种质资源在自然地理分布、群落生态学特性、表型变异规律、系统发育与分类现状、谱系地理及其演化历史、繁育技术、综合利用价值的最新进展。在上述结论的基础上,笔者还提出了当前存在问题与展望,旨在为国产优良樱属种质资源的保育以及新品种的开发利用提供参考。 相似文献
806.
幽门螺杆菌(Helicobacter pylori,H.pylori)在世界范围内感染率高,随着H.pylori对常用抗生素的耐药率逐渐增加,高效的经验性治疗方案亟待探索。新近Maastricht V/Florence共识及我国第五次幽门螺杆菌感染处理共识均推荐含铋剂四联方案可作为一线治疗方案。但是,四联方案存在用药多、药物不良反应多、患者依从性差、部分老年人及肝、肾功能不全的患者无法耐受等缺点。近年来多项研究显示高剂量阿莫西林联合质子泵抑制剂(proton pump inhibitor,PPI)的二联方案与含铋剂四联方案的疗效相近,但用药少,不良反应少,患者依从性更高,有可能成为经验性的一线治疗方案,或成为一线、二线治疗失败后的补救方案。本文就二联方案在H.pylori根除治疗中的应用进展作一综述。 相似文献
807.
Xiao Ouyang Yunzhi Ding Li Yu Feng Xin Xiaowei Yang Peng Sha Songming Tong Qi Cheng Yiqi Xu 《Journal of musculoskeletal & neuronal interactions》2020,20(4):556
Objective:To investigate the clinical effects of dynamic hip screw (DHS) and proximal femoral nail anti-rotation (PFNA) on senile osteoporosis patients and their effects on the expression level of bone-specific alkaline phosphatase (BALP).Methods:116 elderly patients with osteoporotic fracture were divided into DHS group (n=67) and PFNA group (n=49). BALP values were measured by ELISA before operation and 30 days after operation.Results:The operation time, the bleeding volume, and the weight-bearing time of PFNA group was shorter than DHS group (p<0.05); the dominant blood loss and occult blood loss in PFNA group were less than those in DHS group (p<0.05); the healing time and detumescence time, the complications of PFNA group was fewer than the DHS group (p<0.05). The ten-meter walking speed and the five sitting tests in PFNA group were shorter than that in DHS group (p<0.05); the excellent and good rate and Harris score in PFNA group were higher than those in DHS group (p<0.05). The expression of BALP in PFNA group was lower than that in DHS group (p<0.05).Conclusion:PFNA surgery has less trauma, fewer complications, more optimistic postoperative healing and recovery degree, and is more conducive to the reduction of BALP expression level. 相似文献
808.
Jianfa Li ChenChen Huang Yifan Zou Jing Yu Yaoting Gui 《Journal of cellular and molecular medicine》2020,24(12):6609-6621
Growing evidence indicates that circular RNAs (circRNAs) are promising biomarkers, as they play significant roles in the development of various cancers. The circular RNA MYLK (circMYLK) has been reported to be involved in the development of malignant tumours, including liver, prostate and bladder cancers. Nevertheless, the biological function of circMYLK in renal cell carcinoma (RCC) remains unclear. In this study, we observed that circMYLK is notably up‐regulated in RCC. Increased circMYLK expression led to a larger tumour size, distant metastasis and poor prognosis of RCC patients. Moreover, circMYLK silencing repressed RCC growth and metastasis in vitro and in vivo. Mechanistically, circMYLK can capture miR‐513a‐5p to facilitate VEGFC expression and further promote the tumorigenesis of RCC cells. In summary, our findings demonstrate that circMYLK has an oncogenic role in RCC growth and metastasis by modulating miR‐513a‐5p/VEGFC signalling. Thus, circMYLK has potential as a diagnostic biomarker and therapeutic target in the treatment of RCC. 相似文献
809.
Jinwook Kim Dan Ouyang Haifei Lu Fei Ye Yuwei Guo Ni Zhao Wallace C. H. Choy 《Liver Transplantation》2020,10(15)
For ideal flexible transparent electrodes, the features of good electrical/optical properties, low surface roughness, efficient charge transportation, robust electrical stability under simultaneously continuous operation bias, and mechanical bending are critical. Herein, a flexible transparent electrode fulfilling all these features is demonstrated by silver (Ag) nanonetwork composites semi‐embedded in low‐temperature‐processed colorless polyimide (cPI), which shows a figure of merit over 1000 (5.4 Ω sq?1 sheet resistance and >94% diffused transmission at 550 nm wavelength), extremely smooth topography (<1 nm root‐mean‐square roughness and <3 nm peak‐to‐valley roughness), remarkable bending stability under continuous operation bias, and increased work function favoring the band alignment with typical charge transport layers for efficient devices. These characteristics are attributed to one‐step multifunctional chemical treatment on the composite of Ag nanowires and an example polymer of poly(3,4‐ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS). The strategic one‐step process simultaneously offers selective welding at nanowires cross junctions to form an Ag nanonetwork, and removing polyvinylpyrrolidone surfactant from Ag nanowires and PSS from PEDOT:PSS. The flexible electrode also favors the residue‐free cPI transfer for applications. Flexible organic solar cells (OSCs) made from the electrode achieve an averaged power conversion efficiency of 14.46% (best, 15.12%), which is the best flexible OSCs reported so far. 相似文献