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71.
目的:构建pET-42a(+)-HPV58E6E7原核表达质粒,诱导表达人乳头瘤病毒(HPV)58型E6E7融合蛋白。方法:采用PCR方法扩增出HPV58 E6E7融合基因的全长序列,利用DNA重组技术将其定向插入原核表达载体pET-42a(+)中,构建pET-42a(+)-HPV58E6E7原核表达质粒,用限制性内切酶酶切和核酸序列检测对重组质粒进行鉴定;将其转入宿主菌大肠杆菌BL21进行诱导以表达HPV58E6E7融合蛋白,并用谷胱甘肽琼脂糖树脂纯化回收HPV58E6E7融合蛋白,用SDS-PAGE及Western印迹鉴定表达蛋白的相对分子质量及抗原性。结果:PCR、限制性内切酶酶切和核酸序列检测证实重组质粒中插入的目的基因大小、方向正确;HPV58E6E7融合蛋白得到高效原核表达及纯化,表达蛋白的分子大小正确,抗原性良好。结论:pET-42a(+)-HPV58E6E7原核表达质粒构建成功,HPV58E6E7融合蛋白得到高效表达及有效纯化,为检测HPV58型治疗性疫苗的免疫效果提供了抗原。  相似文献   
72.
为了检测HPV 58型不同L1基因的DNA疫苗的免疫原性,以pcDNA3.1为载体分别构建含HFV 58型不同L1基因的DNA疫苗,命名为L1h、L1h△c、L1S、L1SM和L1wt.用免疫印迹法检测各DNA疫苗的体外表达情况;各重组质粒与pcDNA3.1-h58L2和pcDNA3.1-GFP共转染293FT细胞,检测其形成假病毒的能力;并将各DNA疫苗肌肉注射免疫小鼠,利用假病毒中和实验检测中和抗体水平,用ELISPOT检测细胞免疫情况.结果显示,本实验成功构建了五种DNA疫苗,L1h△c的体外表达量最高,L1S和L1SM的表达量次之,L1wt没有表达;重组质粒L1S能够形成假病毒,而其他四种重组质粒均不能形成假病毒.L1S和L1h均可在小鼠体内诱导中和抗体,但L1S诱导的中和抗体的平均滴度为1:6 400,明显高于L1h诱导的中和抗体水平(平均滴度为1:48),而其他疫苗在小鼠体内未产生中和抗体.对五种疫苗均未检测出特异性的细胞免疫反应.结果提示,体外能够组装成假病毒的DNA疫苗在免疫动物后可诱导高滴度的中和抗体,为今后DNA疫苗的筛选提供参考.  相似文献   
73.
人乳头瘤病毒(human papillomavirus,HPV)58型是宫颈癌的主要诱因之一. HPV58在亚洲地区宫颈癌组织中的检出率仅次于HPV16/18. HPV58中和单克隆抗体可用于 HPV病毒样颗粒(virus-like particle,VLP)疫苗的研究,并为病毒感染入侵机制的 研究提供实验材料. 本研究采用HPV58 L1 VLP免疫BALB/c小鼠,取其脾细胞进行杂交瘤 细胞的制备,通过VLP-ELISA和假病毒中和实验筛选杂交瘤细胞株;经rProtein A纯化 阳性杂交瘤细胞培养上清获得单抗;采用ELISA测定型别特异性中和单抗的亲和力,采用相加实验及变性VLP-ELISA分析单抗识别表位的性质;选取高亲和力单抗建立定量分 析HPV58 L1 VLP的ELISA方法. 获得了2株HPV58特异性中和单抗XM-22和XM-23,亲和常数分别为2.7×107 mol-1·L和1.9×106 mol-1·L,二者识别表位可能不同. 同时获得2株具有交叉中和活性的单抗XM-21和XM-24,除可较高水平中和HPV58外,还可分别交叉 中和亲缘关系较远的HPV18和HPV6. 以XM-22建立的ELISA方法定量分析HPV58 L1 VLP的检测范围为0.05 μg/mL~0.40 μg/mL. 本研究建立的ELISA方法可用于HPV58 L1 VLP疫苗生产的质量控制研究,获得的4株具有不同特点的中和单抗可用于HPV58感染入侵机制 的研究.  相似文献   
74.
The purpose of this study was to examine the effects of stress and the role of locally infused anxiogenic-like neuropeptides galanin, CCK-8, vasopressin, substance P and neurokinin A, and anxiolytic-like peptides NPY, nociceptin/orphanin FQ, somatostatin and neurotensin, on modulation of noradrenaline (NA) and cAMP efflux monitored simultaneously by microdialysis in the medial prefronatal cortex of awake rats. Concentrations of cAMP were determined by a newly developed method based on derivatization of cAMP with 2-chloroacetaldehyde followed by HPLC with fluorescence detection. Local infusion of forskolin (10 and 30 μM) dose-dependently increased the cAMP levels to 417% and 1050% of the control group, respectively. Similarly, local infusion of NA (10 μM) increased the cAMP to the peak level of 168%. A 5-min tail pinch and a 10-min swim stress rapidly increased the NA and cAMP levels to 167% and 203% (NA) and 141% and 161% (cAMP), respectively. Infusion of galanin and CCK-8 (0.5 nmol, and 1.5 nmol/0.5 μl) dose-dependently increased NA to the peak levels of 191% and 179% and cAMP levels to 174% and 166%, respectively. The peak levels following infusions of vasopressin, substance P and neurokinin A were 91%, 135% and 86% for NA and 131%, 83% and 76% for cAMP, respectively. Infusions of anxiolytic-like peptides at highest concentrations significantly increased (NPY, 136%) or decreased (nociceptin, 71%; somatostatin, 86%) the NA levels, whereas neurotensin had no effect. The cAMP levels decreased to 86% (NPY, neurotensin), 78% (nociceptin), somatostatin infusion was without effect. The present findings confirmed a close correlation between the stress-induced increases in prefrontal cortical NA and cAMP levels, as well as, concurrent changes in NA and cAMP levels following infusions of galanin and CCK-8 (increased levels) and nociceptin/orphanin FQ (decreased levels). Infusions of other neuropeptides showed a more complex pattern of NA and cAMP responses.  相似文献   
75.
本文用凝胶直读法、末端鉴定法等相配合,测定了樗蚕(Philosamia cynthia)絲腺5SrRNA的核苷酸顺序:AGACAACGUCCAUACCACGUUGAAAACACCGGUUCUCGUCCGAUCACCGAAGUCAAGCAACGUCGGGCGCGGUCAGUACUUGGAUGGGUGACCGCCUGGGAACACCGCGUGCUGUUGGCUU比较了樗蚕、蓖麻蚕、柞蚕、家蚕、果蝇等5SrRNA结构差异,在分子水平上探讨了昆虫的分化。  相似文献   
76.
77.
Dysfunctional vascular smooth muscle (VSM) plays a vital role in the process of atherosclerosis in patients with type 2 diabetes mellitus (T2DM). Alpha-lipoic acid (ALA) can prevent the altered VSM induced by diabetes. However, the precise mechanism underlying the beneficial effect of ALA is not well understood. This study aimed to determine whether ALA ameliorates VSM function by elevating hydrogen sulfide (H2S) level in diabetes and whether this effect is associated with regulation of autophagy of VSM cells (VSMCs). We found decreased serum H2S levels in Chinese patients and rats with type 2 diabetes mellitus (T2DM). ALA treatment could increase H2S level, which reduced the autophagy-related index and activation of the 5′-monophosphate-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR) pathway, thereby protecting vascular function in rats with T2DM. Propargylglycine (PPG), a cystathionine-γ-lyase inhibitor, could weaken the ALA effect. In cultured VSMCs, high glucose level also reduced H2S level, upregulated the autophagy-related index and activated the AMPK/mTOR pathway, which were reversed by concomitant application of sodium hydrosulfide (NaHS, an H2S donor) or ALA. The protective effect of NaHS or ALA was attenuated by rapamycin (an autophagy activator), 5-amino-1-β-d-ribofuranosyl-imidazole-4-carboxamide (an AMPK activator) or PPG. In contrast, Compound C (an AMPK inhibitor) enhanced the effect of ALA or NaHS. ALA may have a protective effect on VSMCs in T2DM by elevating H2S level and downregulating autophagy via the AMPK/mTOR pathway. This study provides a new target for addressing diabetic macroangiopathy.  相似文献   
78.
For the development of potential anti-prostate cancer agents, 24 kinds of novel naftopidil-based arylpiperazine derivatives have been synthesized and characterized by spectroscopic methods. Their antitumor activities were evaluated against several classical prostate cancer cell lines including PC-3, LNCaP, and DU145. Among all the compounds, 9, 13, 17, 21 and 27 showed strong cytotoxic activities against DU145 cells (IC50?<?1?μM). Further testing confirmed that compound 17 inhibited the growth of DU145 cells by inducing cell cycle arrest at G0/G1 phase. Besides, antagonistic activities of compounds (9, 13, 17, 21 and 27) towards a1-ARs (α1A, α1B, and α1D) were further evaluated using dual-luciferase reporter assays, and the compounds 13 and 17 exhibited better a1-ARs subtype selectivity. The structure–activity relationship (SAR) of these developed arylpiperazine derivatives was rationally discussed. Taken together, these results suggested that further development of such compounds may be of great interest.  相似文献   
79.
In animal cells, Golgi apparatus is located near the microtubule organizing center (MTOC) and its position is determined partly by 58K protein. By sodium dodecyl-sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immuno-blotting methods, a 58K-like protein has been found in pollen grains and pollen tubes of Lilium davidii. Its molecular weight is very similar to that of the 58K protein of animal cells. By immunofluorescence labeling, under a confocal laser scanning microscope (CLSM), the animal 58K antibody revealed a punctate staining in pollen grains and pollen tubes, which is consistent with the distribution of Golgi apparatus in plant cells. In addition, immuno-gold labeling and transmission electron microscopy showed that the 58K-like protein bound mainly to the membrane of vesicles-like structure near Golgi apparatus. This is the first demonstration of the 58K-like protein in plant cells.  相似文献   
80.
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