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991.
Ling Chen Hong Xiao Zong-Hua Wang Yi Huang Zi-Peng Liu Hui Ren Hang Song 《BMB reports》2014,47(1):39-44
Increasing data shows miR-29a is a key regulator of oncogenic processes. It is significantly down-regulated in some kind of human tumors and possibly functionally linked to cellular proliferation, survival and migration. However, the mechanism remains unclear. In this study, we report miR-29a is significantly under-expressed in gastric cancer compared to the healthy donor. The microvessel density is negatively related to miR-29a expression in gastric cancer tissues. The ectopic expression of miR-29a significantly inhibits proliferation and invasion of gastric cancer cells. Furthermore, western blot combined with the luciferase reporter assays demonstrate that vascular endothelial growth factor A (VEGF-A) is direct target of miR-29a. This is the first time miR-29a was found to suppress the tumor microvessel density in gastric cancer by targeting VEGF-A. Taken together, these results suggest that miR-29a is a tumor suppressor in gastric cancer. Restoration of miR-29a in gastric cancer may be a promising therapeutic approach. [BMB Reports 2014; 47(1):39-44] 相似文献
992.
993.
994.
Wei Li Jun Hyun Jeong Hee Geon Park Young Ran Lee Meng Li Sang Ki Lee 《Journal of Exercise Nutrition & Biochemistry》2014,18(1):105-110
[Purpose]
This study investigated the effect of endurance exercise on neointimal formation, endothelial-dependant relaxation and FOXO expression in balloon-induced carotid arteries of rats.[Methods]
Male SD(Sprague-Dawley) rats of 8 weeks ages were randomly divided into 3 groups; Sham-operated control (SO, n=10), Balloon-induced control (BIC, n=10), and Balloon-induced exercise (BIE, n=10). Endurance exercise training was performed on treadmill (18 m/min, 0% grade, 60 min/day, 5 days/week, 4 weeks).[Results]
Body weight is significantly reduced in BIE compared with BIC. Neointiaml formation in BIC was significantly higher than SO, but it was significantly recovered in BIE compared with BIC. Endothelial-dependent relaxation in BIC was significantly lower than SO, but it was significantly recovered in BIE compared with BIC and expression of FOXO1 and FOXO3a also were significantly increased BIE compared with BIC.[Conclusion]
These data suggest that endurance exercise inhibits neointimal formation and endothelial-dependent relaxation via FOXO expression in balloon-induce atherosclerosis rat model. 相似文献995.
美洲大蠊Per a7基因的克隆、表达及免疫学鉴定 总被引:1,自引:0,他引:1
根据原肌球蛋白基因序列设计引物,以我国南方地区美洲大蠊Periplaneta Americana RNA为模板,用RT-PCR方法扩增出852 bp的全长编码片段,经序列分析发现该基因与NCBI公布的Per a7有3个核苷酸发生改变。将目的片段克隆到pET24a(+)表达载体中,在大肠杆菌BL21 Star获得表达,融合蛋白的分子量约为33 kD。利用蟑螂过敏性患者血清对表达产物进行Western blotting检测,出现明显的识别条带,说明表达产物具有IgE结合活性。 相似文献
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997.
Construction of an inducible transposon,INAc, to develop a gene tagging system in higher plants 总被引:1,自引:0,他引:1
Charng Yuh-Chyang Pfitzner Artur J.P. Pfitzner Ursula M. Charng-Chang Kai-Fay Chen Chui-mei Tu Jenn Kuo Tsong-Teh 《Molecular breeding : new strategies in plant improvement》2000,6(4):353-367
An inducible transposable element, termed INAc (inducible Activator), was constructed for development of a gene tagging system in higher plants. The advantage of such an inducible element is that, unlike the native transposon, its excision can be induced at any time during plant development and the resulting mutants are stable after removal of the inducer. A fusion of the SA inducible promoter (PR-1a) with the Ac transposase gene was inserted together with a hygromycin resistance gene between ca. 400 bp sequences from each end of the maize Ac element, yielding INAc. The INAc element was introduced into tobacco and tomato plants. A high frequency of spontaneous transposition was apparent in primary transformed tomato calli but not in tobacco calli. Treatment of tobacco plants with salicylic acid induced transposition of INAc in both somatic and germinal tissue, with germinal transposition events being revealed by characterization of the progeny of transformed plants whose flowers were exposed to SA. The INAc element thus exhibits potential for development of an inducible transposon system suitable for gene isolation in heterologous plant species. 相似文献
998.
999.
Fluorescence properties of light-harvesting complex LHCⅡ) in photosystem Ⅱ isolated from spinach (Spinacia oleracea L.) was investigated with the time-resolved fluorescence spectroscopic technique. The sample was excited by double frequency Ti:Al203 laser with 400 nm wavelength and 120 fs width. Fluorescence signal was detected by Boxcar. Three life-time components (320 fs,4.0 ps and 20.0 ps) were obtained by multi-exponential curve model and nonlinear least-square fitting method. Three fluorescence peaks (652 nm, 672 nm, 691 nm) were obtained by Global analysis and Gauss curve fitting. These components were analyzed according to the structural and fluorescence spectroscopic property of LHCⅡ. The fluorescence ratio of each component to that of all the component was 3.4%, 50% and 46.6% respectively. The possible model of energy transfer in LHCⅡ was discussed. 相似文献
1000.
LI Dong-Hai RUAN Xiang XU Qiang GONG Yan-Dao ZHANG Xiu-Fang ZHAO Nan-Ming WANG Ke-Bin KUANG Ting-Yun 《植物学报(英文版)》2004,46(4):423-427
Chlorophyll a fluorescence and circular dichroism (CD) spectra of photosystem Ⅱ (PSⅡ) membrane were measured after heat treatment. The chlorophyll fluorescence parameter Fo' remained stable after treatment at the temperatures from 30 ℃ to 40 ℃ and then reached a maximum after treatment at 55 ℃. In PSⅡ membranes and LHCⅡ (light-harvesting chlorophyll a/b binding complex)-enriched complexes, anomalous CD signals with extremely large amplitudes occurred during the heat treatment. The temperature corresponding to the maximum anomalous CD intensity peaking at 677 nm was 40 ℃. The results indicate that the aggregation state of the LHCⅡ in PSⅡ is related to the anomalous CD signal, and can be an important factor influencing Fo' in the heat treatment of PSⅡ membrane. 相似文献