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231.
目的:探讨表皮生长因子受体抑制剂吉非替尼对敲低膜联蛋白A7后的人肝癌细胞株HepG2细胞增殖的影响,为肝癌的分子靶向治疗提供实验依据。方法:将细胞分为吉非替尼组、siRNA转染、siRNA转染+吉非替尼、转染阴性对照组和空白对照组,用脂质体转染法靶向将ANXA7的siRNA转染入HepG2细胞,在转染后6h在siRNA转染组和siRNA转染组+吉非替尼组加入一定浓度的吉非替尼,加药后72h进行MTT实验以检测细胞增殖活力,从而计算增殖抑制率。结果:MTT检测得知, siRNA转染组、吉非替尼组和siRNA转染+吉非替尼组,对细胞增殖有明显的抑制作用,较对照组差别有统计学意义( P<0.05)。结论:吉非替尼对敲低ANXA7后的HepG2细胞的增殖具有更为明显的抑制作用。 相似文献
232.
Inhibiting effect of antisense hTRT on telomerase activity of human liver cancer cell line SMMC-7721
Objective: To induce changes in biological character of human liver cancer cell line SMMC-7721 by blocking the expression of telomerase genes hTRT and to explore its value in cancer gene therapy. Methods: The vehicle for eukaryotic expression of antisense hTRT was constructed and then transfected into SMMC-7721 cells. The effects of antisense hTRT gene on telomerase activity, cancer cell growth and malignant phenotypes were analyzed. Results: The obtained transfectants that could express antisense hTRT gene stably showed marked decrease in telomerase activity;the shortening of telomere was obvious; cells presented contact growth inhibition; in nude mice transplantation, the rate of tumor induction dramatically decreased. Conclusion : Antisense hTRT gene expression can significantly inhibit telomerase activity of cancer cells and decrease malignant phenotypes in vitro and in vivo. Therefore, as a telomerase inhibitor, antisense hTRT gene may be a new pathway for cancer therapy. 相似文献
233.
目的探讨shRNA真核表达质粒介导的RNA干扰技术对人结肠癌LoVo细胞哺乳动物雷帕霉素靶蛋白(mTOR)基因表达的抑制作用。方法合成编码shRNA的特异性DNA序列,连接到质粒pGenesil-1,采用脂质体Lipofectamine^TM 2000转染LoVo细胞,G418筛选4周。根据转染质粒的不同,实验分为3组:A组(正常对照组)为未转染的正常培养LoVo细胞,B组(阴性对照组)为转染pGenesil-1空载体质粒,C组(阳性实验组)为转染质粒pGenesil-1-mTOR。采用逆转录聚合酶链反应(RT—PCR)法检测LoVo细胞mTOR基因mRNA表达,免疫印迹(Western blot)法检测mTOR蛋白表达。结果双酶切产物琼脂糖凝胶电泳显示,重组质粒pGenesil-1-mTOR和空载体质粒pGenesil-1分别切出一条410、350bp大小的片段。G418筛选的转染细胞在倒置荧光照相显微镜下可观察到绿色荧光。C组LoVo细胞mTOR基因mRNA表达水平明显低于A组(P〈0.05),表达抑制率为73.0%。C组LoVo细胞mTOR蛋白表达水平明显低于A组(P〈0.05),表达抑制率为72.5%。结论shRNA真核表达质粒介导的RNA干扰可明显抑制人结肠癌LoVo细胞mTOR基因表达。 相似文献
234.
海南岛不明发热病人血虫媒病毒分离鉴定及抗体检测 总被引:2,自引:0,他引:2
目的从海南岛不明发热病人血中分离和鉴定虫媒病毒,并在当地人群进行抗体检测,以了解南方地区虫媒病毒的感染情况。方法采用微量法细胞培养对205份发热原因不明患者血标本进行病毒分离,应用生物学性状检测、间接免疫荧光试验(IFA)和血凝抑制试验(HI)等技术对分离病毒进行鉴定。采用IFA检测从当地人群血清中分离出的病毒的抗体水平。结果从发热早期患者血标本中分离出2株病毒,鉴定为甲病毒,命名为HF 7和HC 6。这2株病毒与8种甲病毒免疫腹水中的SIN的免疫腹水呈现最高的血凝抑制滴度(分别为1∶160和1∶320),与SIN免疫腹水的交叉荧光效价最高(分别为1∶320和1∶640),但HF 7和HC 6病毒的免疫腹水与8种甲病毒的血凝抑制试验和交叉免疫荧光试验无反应,表明HF 7和HC 6病毒虽与SIN病毒的免疫腹水血抑效价及荧光效价高,但HF 7和HC 6的免疫腹水与SIN病毒无抑制效价和免疫荧光效价。当地人群对这两株病毒感染的抗体阳性率分别为3.3%(15/451)和8.4%(38/451)。结论HF7和HC6为甲病毒的一个新种。海南岛人群存在甲病毒感染。 相似文献
235.
香菇和黄芪混合多糖抑制S—180肉瘤生长和增强免疫作用的研究 总被引:3,自引:0,他引:3
经口给予香菇多糖与黄芪多糖混合物,抑制动物移植性肿瘤重复实验结果一致显示,香菇多糖与黄芪多糖混合物在150.0mg/kg.BW/d剂量时可以抑制S—180移植性肉瘤的生长;小鼠腹腔巨噬细胞吞噬鸡红细胞作用实验显示,香菇多糖与黄芪多糖混合物在37.5mg/kg.BW/d剂量(及以上剂量)时具有提高小鼠吞噬细胞功能的作用;小鼠脾NK细胞活性测定结果表明,香菇多糖与黄芪多糖混合物在37.5mg/kg.BW/d剂量(及以上剂量)时具有增强NK细胞活性的作用。且上述三个实验均显示良好的剂量—反应关系 相似文献
236.
Lingbo Wang Michael Crennan Angela Benic Derek Chiu Fiona Morris Denise E. Jackson 《Transfusion medicine and hemotherapy : offizielles Organ der Deutschen Gesellschaft fur Transfusionsmedizin und Immunhamatologie》2022,49(3):180
IntroductionThe Bombay phenotype is a rare blood group determined by the absence of H antigens. Bombay individuals produce anti-H, a clinically significant antibody that react against all ABO blood group. Anti-H can mask underlying alloantibody during antibody investigation, a challenge in current transfusion practice. The aim of this article is to explore saliva inhibition, a novel method to detect underlying alloantibody in Bombay individuals.Case PresentationThe case is a 93-year-old female transfused with pre-donated autologous blood for a surgery. We determined anti-H subclass and thermal amplitude, secretor status, and optimal ratio of saliva and Bombay plasma. Plasma samples containing anti-H were spiked with anti-Fy(a) to determine the effectiveness of saliva inhibition in uncovering underlying alloantibodies.ResultsAnti-H was confirmed to be predominately IgM with broad thermal amplitude. Tube immediate spin (IS) showed stronger anti-H reactivity compared to column agglutination technology (CAT). Spiked anti-Fy(a) was successfully detected using saliva inhibition method.ConclusionTube IS appears more sensitive to anti-H. Saliva inhibition appears to be a promising method to detect underlying alloantibody in the plasma of Bombay phenotype individuals. 相似文献
237.
Roberta Ibba Federico Riu Ilenia Delogu Ilenia Lupinu Gavino Carboni Roberta Loddo Sandra Piras Antonio Carta 《Viruses》2022,14(6)
Bovine viral diarrhea virus (BVDV), also known as Pestivirus A, causes severe infection mostly in cattle, but also in pigs, sheep and goats, causing huge economical losses on agricultural farms every year. The infections are actually controlled by isolation of persistently infected animals and vaccination, but no antivirals are currently available to control the spread of BVDV on farms. BVDV binds the host cell using envelope protein E2, which has only recently been targeted in the research of a potent and efficient antiviral. In contrast, RdRp has been successfully inhibited by several classes of compounds in the last few decades. As a part of an enduring antiviral research agenda, we designed a new series of derivatives that emerged from an isosteric substitution of the main scaffold in previously reported anti-BVDV compounds. Here, the new compounds were characterized and tested, where several turned out to be potent and selectively active against BVDV. The mechanism of action was thoroughly studied using a time-of-drug-addition assay and the results were validated using docking simulations. 相似文献
238.
目的观察血水草生物碱(Eomecon chionantha Alkaloids,ECA)及其血根碱(Sanguinarine,SAN)的抑菌作用。方法以大肠埃希菌、金黄色葡萄球菌、铜绿假单胞菌、白假丝酵母菌为受试菌,采用琼脂打孔扩散法和琼脂平板稀释法,研究ECA及SAN的抑菌作用。结果 ECA和SAN可抑制大肠埃希菌、金黄色葡萄球菌、白假丝酵母菌的生长,而对铜绿假单胞菌无抑制作用;ECA对大肠埃希菌、金黄色葡萄球菌、白假丝酵母菌的最低抑菌浓度(MIC)分别为40、160、40μg/ml;SAN对大肠埃希菌、金黄色葡萄球菌、白假丝酵母菌的MIC分别为40、80、40μg/ml。结论 ECA和SAN对大肠埃希菌、金黄色葡萄球菌和白假丝酵母菌具有较强的抑菌效果,对铜绿假单胞菌没有明显的抑制作用。 相似文献
239.
《International journal of food sciences and nutrition》2013,64(4):387-392
The dichloromethane (DCM), acetone, ethyl acetate and methanol extracts of the leaves and berries of Myrtus communis L. were screened against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (TYRO), the enzymes linked to neurodegenerative diseases, at 200 μg ml? 1. Antioxidant activity was tested using radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and N,N- dimethyl-p-phenylenediamine (DMPD) radicals, metal chelation capacity, ferric-reducing antioxidant power (FRAP) and phosphomolybdenum-reducing antioxidant power (PRAP) assays. Total phenol and flavonoid quantification of the extracts was calculated spectrophotometrically. The extracts showed a moderate AChE (17.49 ± 3.99% to 43.15 ± 1.55%) and TYRO inhibition (4.48 ± 1.50% to 40.53 ± 0.47%). The leaf extracts were ineffective against BChE, while the berry extracts displayed inhibition between 21.83 ± 3.82% and 36.80 ± 2.00%. The polar extracts exerted remarkable scavenging effect against DPPH and DMPD and also in the FRAP assay, where the DCM extract of the berries had the best metal chelation capacity (79.29 ± 1.14%). This is the first study that demonstrates in vitro neuroprotective effects of myrtle. 相似文献
240.
Toxicity of Organotin Compounds to Activated Sludge 总被引:3,自引:0,他引:3
Athanasios S. Stasinakis Nikolaos S. Thomaidis Themistokles D. Lekkas 《Ecotoxicology and environmental safety》2001,49(3):275-280
Inhibition of respiration rate of activated sludge heterotrophic microorganisms was determined for tributyltin (TBT), dibutyltin (DBT), monobutyltin (MBT), and triphenyltin (TPhT). TBT, DBT, and TPhT exhibit similar acute toxicity to activated sludge, while MBT is less toxic. The effect of various experimental parameters, such as sludge age, concentrations of suspended solids, and exposure time, on toxicity was investigated. An increase in sludge age or in the concentration of suspended solids reduces the observed inibition. Longer exposure seems to increase the inhibition of TBT, DBT, and TPhT during the first hours of exposure, while later the inhibition remains constant. In the case of MBT, 24 h after exposure, the respiration rate was similar to that of the control biomass. 相似文献