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71.
Liu Q He X Liu Y Du B Wang X Zhang W Jia P Dong J Ma J Wang X Li S Zhang H 《Biochemical and biophysical research communications》2008,377(3):775-779
Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in X-ray-induced cell death. Under X-ray irradiation, the upregulation of the expression of NADPH oxidase membrane subunit gp91phox was dose-dependent. Meanwhile, the cytoplasmic subunit p47phox was translocated to the cell membrane and localized with p22phox and gp91phox to form reactive NADPH oxidase. Our data suggest, for the first time, that NADPH oxidase-mediated generation of ROS is an important contributor to X-ray-induced cell death. This suggests a new target for combined gene transfer and radiotherapy. 相似文献
72.
LC-MS/MS determination of helicid in human plasma and its application in pharmacokinetic studies 总被引:1,自引:0,他引:1
Xie H Jia Y Tan Z Zhang W Chen R Sun H Shen J Zhou H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(30):3607-3611
Helicid is a traditional Chinese medicine used to treat headache and insomnia with definite effects. To facilitate pharmacokinetic studies of helicid in man, a sensitive and specific LC-MS/MS method for the quantitative detection of helicid in human plasma was developed and validated. The method involved the addition of bergeninum as the internal standard (IS), protein precipitation, HPLC separation, and quantification by MS/MS system using negative electrospray ionization in the multiple reaction monitoring mode (MRM). The precursor→product ion transitions were monitored at m/z 282.8→120.9 for helicid and m/z 326.9→192.2 for the IS, respectively. The lower limit of quantification (LLOQ) was 0.2 μg/L. The calibration curves for helicid was linear over a concentration range of 0.2-20 μg/L. The intra- and inter-batch analyses of QC samples at 0.4, 2, 20 μg/L indicated good precision (%R.S.D. between 2.69 and 5.47%) and accuracy (between 96.15 and 105.05%). The helicid was stable in human plasma stored at room temperature for at least 24h, 4°C for at least 24h, -20°C for at least 1 month, and for routine three freeze-thaw cycles. This accurate and specific assay provides a useful method for evaluating the pharmacokinetic profile of helicid in humans. 相似文献
73.
74.
以谷胱甘肽为电子供体的细胞膜氧化还原系统 总被引:1,自引:0,他引:1
内载谷胱甘肽(GSH)的大豆(Glycine max L.)下胚轴正向型质膜囊泡具有以GSH为电子供体的跨膜电子传递活性,能还原膜外电子受体FeCN和细胞色素(Cyt)C,其还原速率分别为(21.6±0.6)nmolFeCN·min~(-1)·mg~(-1)蛋白和(6.6±1.0)nmol Cyt C·min~(-1)·mg~(-1)蛋白。这种跨膜电子传递能引起膜上Cyt P-450吸收光谱标志带(Soret带)的变化,表明Cyt P-450参与了这一氧化还原过程。在跨质膜电子传递的同时伴随着H~ 运输和膜电位的改变。 相似文献
75.
Dong Zheng Qiang Sun Zhaoliang Su Fanzhi Kong Xiaoju Shi Jia Tong Pei Shen Tianqing Peng Shengjun Wang Huaxi Xu 《PloS one》2013,8(4)
The outer membrane protein RagB is one of the major virulence factors of the periodontal pathogen Porphyromonas gingivalis (P. gingivalis). In order to induce protective immune response against P. gingivalis infection, an mGITRL gene-linked ragB DNA vaccine (pIRES-ragB-mGITRL ) was constructed. Six-week-old female BALB/c mice were immunized with pIRES-ragB-mGITRL through intramuscular injection and then challenged by subcutaneous injection in the abdomen with P. gingivalis. RagB-specific antibody-forming cells were evaluated by an Enzyme-linked immunosorbent spot, and specific antibody was determined by enzyme-linked immunosorbent assay. In addition, the frequencies of Tfh and IFN-γ+ T cells in spleen were measured using flow cytometer, and the levels of IL-21 and IFN-γ mRNA or proteins were detected by real time RT-PCR or ELISA. The data showed that the mGITRL-linked ragB DNA vaccine induced higher levels of RagB-specific IgG in serum and RagB-specific antibody-forming cells in spleen. The frequencies of Tfh and IFN-γ+ T cells were obviously expanded in mice immunized by pIRES-ragB-mGITRL compared with other groups (pIRES or pIRES-ragB ). The levels of Tfh and IFN-γ+ T cells associated cytokines were also significantly increased in pIRES-ragB-mGITRL group. Therefore, the mice immunized with ragB plus mGITRL showed the stronger resistant to P. gingivalis infection and a significant reduction of the lesion size caused by P. gingivalis infection comparing with other groups. Taken together, our findings demonstrated that intramuscular injection of DNA vaccine ragB together with mGITRL induced protective immune response dramatically by increasing Tfh and IFN-γ+ T cells and antibody production to P. gingivalis. 相似文献
76.
77.
Chiyu Li Jia Chen Xiaoyan Li Xin Zhang Ying Liu Sirui Zhu Long Wang Heping Zheng Sheng Luan Jiada Li Feng Yu 《植物学报(英文版)》2022,64(10):1901-1915
Plant shoot phototropism is triggered by the formation of a light-driven auxin gradient leading to bending growth. The blue light receptor phototropin 1(phot1) senses light direction, but how this leads to auxin gradient formation and growth regulation remains poorly understood. Previous studies have suggested phot1’s role for regulated apoplastic acidification, but its relation to phototropin and hypocotyl phototropism is unclear. Herein, we show that blue light can cause phot1 to interact with... 相似文献
78.
79.
目前,对胚状体发生过程中的生理生化研究表明,这一过程伴随有核酸、蛋白质等大分子物质合成速度的增加及与胚胎发生有关的特异性蛋白的合成;一些同工酶,如过氧化物酶、脂酶、细胞色素氧化酶和谷氨酸脱氢酶 相似文献
80.