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981.
Loss of TAB3 expression by shRNA exhibits suppressive bioactivity and increased chemical sensitivity of ovarian cancer cell lines via the NF‐κB pathway 下载免费PDF全文
Chengwei Duan Jie Chen Ming Su Yunfeng Jin Yan Deng Di Wang Caiwen Chen Linsen Zhou Jialin Cheng Wei Wang Qinghua Xi 《Cell proliferation》2016,49(6):657-668
Ovarian cancer is a leading cause of death among gynaecologic malignancies. Despite many years of research, it still remains sparing in reliable diagnostic markers and methods for early detection and screening. Transforming growth factor β‐activated protein kinase 1 (TAK1)‐binding protein 3 (TAB3) was initially characterized as an adapter protein essential for TAK1 activation in response to IL‐1β or TNFα, however, the physiological role of TAB3 in ovarian cancer tumorigenesis is still not fully understood. In this study, we evaluated the effects of TAB3 on ovarian cancer cell lines. Expressions of TAB3 and PCNA (proliferating cell nuclear antigen) were found to be gradually increased in EOC tissues and cell lines, by western blot analysis and qRT‐PCR. Distribution of TAB3 was further analysed by immunohistochemistry. In vitro, knockdown of TAB3 expression in HO8910 or SKOV3 ovarian cancer cells significantly inhibited bioactivity of ovarian cancer cells, including proliferation and cell‐cycle distribution, and promoted chemical sensitivity to cisplatin and paclitaxel treatment via inhibiting NF‐κB pathways. In conclusion, our study strongly suggests a novel function of TAB3 as an oncogene that could be used as a biomarker for ovarian cancer. It provides a new insight into the potential mechanism for therapeutic targeting, in chemotherapy resistance, common in ovarian cancer. 相似文献
982.
Chun Fu Lin Sanford P. C. Hsu Chung Jung Lin Wan Yuo Guo Chih Hsiang Liao Wei Fa Chu Sheng Che Hung Yang Shin Shih Yen Tzu Lin 《PloS one》2016,11(3)
Purpose
We sought to imitate angiographic cerebral circulation time (CCT) and create a similar index from baseline CT perfusion (CTP) to better predict vasospasm in patients with subarachnoid hemorrhage (SAH).Methods
Forty-one SAH patients with available DSA and CTP were retrospectively included. The vasospasm group was comprised of patients with deterioration in conscious functioning and newly developed luminal narrowing; remaining cases were classified as the control group. The angiography CCT (XA-CCT) was defined as the difference in TTP (time to peak) between the selected arterial ROIs and the superior sagittal sinus (SSS). Four arterial ROIs were selected to generate four corresponding XA-CCTs: the right and left anterior cerebral arteries (XA-CCTRA2 and XA-CCTLA2) and right- and left-middle cerebral arteries (XA-CCTRM2 and XA-CCTLM2). The CCTs from CTP (CT-CCT) were defined as the differences in TTP from the corresponding arterial ROIs and the SSS. Correlations of the different CCTs were calculated and diagnostic accuracy in predicting vasospasm was evaluated.Results
Intra-class correlations ranged from 0.96 to 0.98. The correlations of XA-CCTRA2, XA-CCTRM2, XA-CCTLA2, and XA-CCTLM2 with the corresponding CT-CCTs were 0.64, 0.65, 0.53, and 0.68, respectively. All CCTs were significantly prolonged in the vasospasm group (5.8–6.4 s) except for XA-CCTLA2. CT-CCTA2 of 5.62 was the optimal cut-off value for detecting vasospasm with a sensitivity of 84.2% and specificity 82.4%Conclusion
CT-CCTs can be used to interpret cerebral flow without deconvolution algorithms, and outperform both MTT and TTP in predicting vasospasm risk. This finding may help facilitate management of patients with SAH. 相似文献983.
Jiandong Zhang Zhimei Cui Honghong Chang Xiaojun Fan Qiuyong Zhao Wenlong Wei 《Biotechnology letters》2016,38(9):1559-1564
Objectives
To investigate the efficiency of a cofactor regeneration enzyme co-expressed with a glycerol dehydrogenase for the production of 1,3-dihydroxyacetone (DHA).Results
In vitro biotransformation of glycerol was achieved with the cell-free extracts containing recombinant GlyDH (glycerol dehydrogenase from Escherichia coli), LDH (lactate dehydrogenase form Bacillus subtilis) or LpNox1 (NADH oxidase from Lactobacillus pentosus), giving DHA at 1.3 g l?1 (GlyDH/LDH) and 2.2 g l?1 (GlyDH/LpNox1) with total turnover number (TTN) of NAD+ recycling of 6039 and 11100, respectively. Whole cells of E. coli (GlyDH–LpNox1) co-expressing both GlyDH and LpNox1 were constructed and converted 10 g glycerol l?1 to DHA at 0.2–0.5 g l?1 in the presence of zero to 2 mM exogenous NAD+. The cell free extract of E. coli (GlyDH–LpNox) converted glycerol (2–50 g l?1) to DHA from 0.5 to 4.0 g l?1 (8–25 % conversion) without exogenous NAD+.Conclusions
The disadvantage of the expensive consumption of NAD+ for the production of DHA has been overcome.984.
985.
986.
987.
运用典型相关分析等多元统计方法对福建省火炬松(Pinus taeda Linn.)人工林的生长与环境因子间的相互关系进行分析。结果表明,对地处亚热带的福建省而言,火炬松的生长性状除了与年龄、密度有关外,与年均温、≥10℃积温呈正相关,与年降水量呈负相关,从而为火炬松的栽培区划和生产力评价提供科学依据。 相似文献
988.
中国东北产6种藓类植物的染色体观察 总被引:2,自引:0,他引:2
苔藓植物细胞学研究始于 2 0世纪 [1 ] 。我国有关这方面的研究自 1 988年开始 ,据 1 998年周云龙统计 ,国内学者共报道了 94种苔藓植物的染色体数目 ,其中苔类有 1 6科、1 9属、2 3种 ,5种为首次报道 ;藓类有 2 1科、37属、71种 ,2 7种为首次报道[2 ] 。这些研究为苔藓植物的系统学、生态学、遗传学等提供了直接或间接的资料和证据。1 材料和方法将采集的苔藓植物培养在室内北窗台上。取生长旺盛的茎尖用对二氯苯饱和水溶液预处理 5~ 7h,卡诺固定液 (纯酒精∶冰醋酸 =3∶ 1 )固定 ,95%酒精∶盐酸 ( 1∶ 1 )离析1 0~ 2 0 min后剥离茎尖… 相似文献
989.
Yu-Chi Chang Wei-Fang Lee Sheng-Wei Feng Haw-Ming Huang Che-Tong Lin Nai-Chia Teng Wei Jen Chang 《PloS one》2016,11(1)
Background
Glow discharge plasma (GDP) procedure is an effective method for grafting various proteins, including albumin, type I collagen, and fibronectin, onto a titanium surface. However, the behavior and impact of titanium (Ti) surface modification is yet to be unraveled.Purpose
The purpose of this study is to evaluate and analyze the biological properties of fibronectin-grafted Ti surfaces treated by GDP.Materials and Methods
Grade II Ti discs were initially cleaned and autoclaved to obtain original specimens. Subsequently, the specimens were GDP treated and grafted with fibronectin to form Ar-GDP (Argon GDP treatment only) and GDP-fib (fibronectin coating following GDP treatment) groups. Blood coagulation test and MG-63 cell culture were performed to evaluate the biological effects on the specimen.Results
There was no significant difference between Ar-GDP and GDP-fib groups in blood compatibility analysis. While in the MTT test, cellular proliferation was benefited from the presence of fibronectin coating. The numbers of cells on Ar-GDP and GDP-fib specimens were greater than those in the original specimens after 24 h of culturing.Conclusions
GDP treatment combined with fibronectin grafting favored MG-63 cell adhesion, migration, and proliferation on titanium surfaces, which could be attributed to the improved surface properties. 相似文献990.
Fang Z Li T Wang Q Zhang X Peng H Fang W Hong Y Ge H Xiao Y 《Applied microbiology and biotechnology》2011,89(4):1103-1110
Laccases are blue multicopper oxidases with potential applications in environmental and industrial biotechnology. In this
study, a new bacterial laccase gene of 1.32 kb was obtained from a marine microbial metagenome of the South China Sea by using
a sequence screening strategy. The protein (named as Lac15) of 439 amino acids encoded by the gene contains three conserved
Cu2+-binding domains, but shares less than 40% of sequence identities with all of the bacterial multicopper oxidases characterized.
Lac15, recombinantly expressed in Escherichia coli, showed high activity towards syringaldazine at pH 6.5–9.0 with an optimum pH of 7.5 and with the highest activity occurring
at 45 °C. Lac15 was stable at pH ranging from 5.5 to 9.0 and at temperatures from 15 to 45 °C. Distinguished from fungal laccases,
the activity of Lac15 was enhanced twofold by chloride at concentrations lower than 700 mM, and kept the original level even
at 1,000 mM chloride. Furthermore, Lac15 showed an ability to decolorize several industrial dyes of reactive azo class under
alkalescent conditions. The properties of alkalescence-dependent activity, high chloride tolerance, and dye decolorization
ability make the new laccase Lac15 an alternative for specific industrial applications. 相似文献