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1.
目的:观察淫羊藿甙抗辐射损伤作用,并探讨其抗辐射损伤机制。方法:KM种小鼠于60Coγ射线照射前48,24h及照后即刻灌胃淫羊藿甙,剂量分别为1,10,100mg/kg,照射剂量8.0Gy,观察受照射小鼠30d存活率和死亡动物平均存活时间。另外观察淫羊藿甙对l锄种小鼠受5.5Gy 60Coγ射线照射后小鼠胸腺、脾脏和骨髓细胞凋亡率、半胱天冬酶-3(caspase-3)和半胱天冬酶-8(caspase-8))活性的影响。结果:中剂量淫羊藿甙组30d存活率较照射对照组提高50%,死亡动物平均存活时间延长2.5d。照射对照组胸腺、脾脏和骨髓细胞在照射后6,12和24h均有凋亡。胸腺和脾脏于照射后12h凋亡率最高,骨髓于照后6h凋亡率最高。照射24h后,3种组织的凋亡串均明显降低。中剂量淫羊藿甙可降低照射后6,12h胸腺、脾脏、骨髓细胞凋亡率和照射后24h脾脏、骨髓细胞凋亡率,抑制照射后6hcaspase-3活性,对半胱天冬酶-8活性无影响。结论:淫羊藿甙具有抗辐射损伤作用,其机制之一可能是通过抑制caspase-3活性降低细胞凋亡率。  相似文献   

2.
目的研究去乙酰化酶转移酶抑制剂曲古抑菌素A(TSA)对人胃癌细胞SGC-7901的凋亡诱导作用及其机制。方法利用细胞计数、流式细胞仪及末端脱氧核苷酸转移酶生物素dUTP切口末端标记法(TUNEL)研究TSA对胃癌细胞SGC-7901的凋亡诱导作用。利用蛋白印迹法、基因芯片及实时定量PCR研究TSA对胃癌细胞凋亡相关基因表达的影响。结果TSA可诱导胃癌细胞SGC-7901发生凋亡;TSA可增加胃癌细胞SGC-7901p53,bax等基因的表达,降低BCL-2、生存素和半胱天冬酶的表达;TSA可使凋亡诱导因子抗侵袭因子(AIF)和核酸内切酶EndoG从线粒体释放并转移到细胞核内;TSA可通过调控多个凋亡相关基因的表达诱导胃癌细胞发生凋亡,且该凋亡是半胱天冬酶非依赖性的。结论TSA可通过调控多个凋亡相关基因来实现其诱导胃癌细胞凋亡的作用,这种凋亡诱导作用是通过半胱天冬酶非依赖途径进行的。  相似文献   

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目的 探讨NF-kB p65对X射线诱导人非霍奇金淋巴瘤(non-Hodgkin lymphoma,NHL)细胞凋亡的作用及其调控机制.方法 以NF-kB p65抑制剂quinazoline (QNZ)处理人NHL细胞.将NHL细胞株Namalwa、Ramos和Raji细胞分为空白对照组、单纯照射组(IR)和X射线+QNZ实验组( IR+ QNZ),采用Annexin-V染色方法检测肿瘤细胞凋亡水平的变化,采用Western blot方法检测各细胞株中Survivin及凋亡相关蛋白Bax、Bcl-2和Cleaved Caspase-3的表达水平;应用实时定量PCR方法检测Survivin mRNA水平.结果 应用流式细胞仪检测凋亡细胞百分比,结果显示,QNZ处理后进行照射与单纯照射组相比凋亡细胞明显增加,且具有药物浓度依赖性(t=2.93~12.52,P<0.05),Western blot法检测结果显示,电离辐射可显著增加人NHL细胞中Survivin蛋白的表达.而应用1、10和50 nmol/L QNZ处理人NHL细胞24 h后进行照射,可显著下调电离辐射所诱导的NHL细胞中的Survivin蛋白表达.随药物浓度增加其作用更为明显(t=3.29~ 16.72,P<0.05).同时凋亡相关蛋白Bcl-2表达减低,而Bax和Cleaved caspase-3蛋白表达增加,Bcl-2/Bax比值明显降低,与单纯照射组相比,差异有统计学意义(t =6.20 ~9.91,P<0.05).预处理QNZ后射线诱导的3种NHL细胞Survivin mRNA均不同程度下降.结论 抑制NF-kB能够增加X射线诱导的NHL细胞凋亡,其机制可能与下调Survivin蛋白表达水平及对凋亡相关蛋白Bcl-2家族的调节有关.  相似文献   

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目的探查干扰素λ诱导人食管癌YES5和T.Tn细胞抗增殖的机制。方法流式细胞术检测细胞周期,膜联蛋白Ⅴ(annexinⅤ)和PI双染检测凋亡,Western印迹检测凋亡蛋白的表达。结果干扰素λ诱导人食管癌YES5和T.Tn细胞的亚G1期(sub-G1)升高,干扰素λ处理细胞与膜联蛋白Ⅴ的结合增加,干扰素λ可诱导细胞内半胱天冬酶(caspase)3的剪切,caspase抑制剂可减少干扰素λ诱导的sub-G1期升高。结论干扰素λ可诱导人食管癌YES5和T.Tn细胞发生凋亡。  相似文献   

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凋亡相关斑点样蛋白ASC真核表达质粒的构建及表达   总被引:1,自引:0,他引:1  
目的构建凋亡相关的斑点样蛋白(apoptosis-associated speck-like protein containing CARD,ASC)真核表达质粒。方法从人胚肾细胞系HEK293T细胞的总RNA中经过逆转录和PCR获得ASC的全长cDNA双链片段,经过酶切后连接到真核表达载体pcDNA3/flag中,挑选出转化生成的阳性克隆测序,将序列正确的重组质粒命名为pcDNA3/flag-ASC。脂质体转染pcDNA3/flag-ASC质粒到HEK293T细胞中,用Western印迹检测目的蛋白的表达。同时用免疫沉淀和免疫印迹方法检测ASC蛋白与前半胱天冬酶(pro-caspase)-1的相互作用,并用ELISA方法检测ASC蛋白对IL-1β分泌的影响。结果 Western印迹实验证明pcDNA3/flag-ASC可以在HEK293T细胞中表达ASC,并且可以与pro-caspase-1结合,使IL-1β分泌明显降低。结论构建了重组质粒pcDNA3/flag-ASC,在细胞中表达ASC后具有与pro-caspase-1结合的能力,并具有降低IL-1β分泌的生物活性。  相似文献   

6.
鞘氨醇激酶调节细胞凋亡的研究进展   总被引:1,自引:0,他引:1  
鞘磷脂衍生物神经酰胺(Cer)、鞘氨醇(Sp)及1-磷酸鞘氨醇(SIP)在调控细胞增殖、存活及凋亡中发挥着重要作用。鞘氨醇激酶(SPK1)是调控细胞内Cer、Sp、SIP代谢平衡的关键酶。SPK1磷酸化Sp生成SIP,SIP通过细胞内和细胞外作用机制调节细胞生长和凋亡。SPK1参与细胞因子的信号传递。高表达SPK1抑制半胱天冬酶的裂解并上调Bcl-2基因的表达。本文综述了SPK的结构、调控及对细胞凋亡的调节作用。  相似文献   

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目的 探讨NF-κB p65对X射线诱导人非霍奇金淋巴瘤(non-Hodgkin lymphoma, NHL)细胞凋亡的作用及其调控机制。方法 以NF-κB p65抑制剂quinazoline(QNZ)处理人NHL细胞。将NHL细胞株Namalwa、Ramos和 Raji细胞分为空白对照组、单纯照射组(IR)和X射线+QNZ实验组(IR+QNZ),采用Annexin-Ⅴ染色方法检测肿瘤细胞凋亡水平的变化,采用Western blot方法检测各细胞株中Survivin及凋亡相关蛋白Bax、Bcl-2和Cleaved Caspase-3的表达水平;应用实时定量PCR方法检测Survivin mRNA水平。结果 应用流式细胞仪检测凋亡细胞百分比,结果显示,QNZ处理后进行照射与单纯照射组相比凋亡细胞明显增加,且具有药物浓度依赖性(t=2.93~12.52, P<0.05),Western blot法检测结果显示,电离辐射可显著增加人NHL细胞中Survivin蛋白的表达。而应用1、10和50 nmol/L QNZ处理人NHL细胞24 h后进行照射,可显著下调电离辐射所诱导的NHL细胞中的Survivin蛋白表达。随药物浓度增加其作用更为明显(t=3.29~16.72,P<0.05)。同时凋亡相关蛋白Bcl-2表达减低,而Bax和Cleaved caspase-3蛋白表达增加,Bcl-2/Bax比值明显降低,与单纯照射组相比,差异有统计学意义(t=6.20~9.91, P<0.05)。预处理QNZ后射线诱导的3种NHL 细胞Survivin mRNA均不同程度下降。结论 抑制NF-κB能够增加X射线诱导的NHL细胞凋亡,其机制可能与下调Survivin蛋白表达水平及对凋亡相关蛋白Bcl-2家族的调节有关。  相似文献   

8.
目的研究X线照射在体外培养人肝癌细胞株HepG2后,膜TNFR-p75表达变化情况。方法免疫细胞化学检测TNFR-p75蛋白的表达,流式细胞仪分析细胞凋亡率,光镜及电镜观察细胞形态变化。结果X线照射后的TNFR-p75蛋白表达显著增强(P<0.05);光镜及电镜发现细胞体积缩小,变圆,胞浆浓缩,核固缩深染;流式细胞仪分析细胞凋亡率显著增高。结论X线可通过上调TNFR-p75蛋白的表达,诱导细胞凋亡来发挥其抗增殖作用。  相似文献   

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目的 探讨辐射诱导表达载体pEgr-hPTEN体外稳定转染人胶质瘤SHG-44细胞后联合X射线照射,诱导细胞凋亡的作用及凋亡相关蛋白Bcl-2表达的变化。方法 以脂质体介导携有外源野生型PTEN基因的辐射诱导表达载体pEgr-hPTEN,体外转染SHG-44细胞,筛选稳定转染的细胞克隆并扩增培养;应用电子显微镜、流式细胞仪等方法,检测稳定转染联合X射线照射对胶质瘤细胞超微结构、细胞凋亡及Bcl-2蛋白表达等特性的影响。结果 稳定转染细胞超微结构有明显的退行性改变,可见核内染色质趋边的类似早期凋亡的改变;稳定转染联合X射线照射可诱导肿瘤细胞凋亡,5Gy以内随吸收剂量的增加,早期凋亡细胞百分数明显增加,稳定转染不同剂量照射组早期凋亡细胞百分数分别为稳定转染0Gy假照组的1.5—2.3倍、为未转染照射组的1.9—4.4倍、为未转染0Gy假照组的3.4—5.1倍;同时稳定转染细胞Bcl-2蛋白表达则呈剂量依赖性下降。结论 体外PTEN基因转染联合X射线照射可诱导肿瘤细胞凋亡明显增多,Bcl-2蛋白表达下调,具有显著的肿瘤抑制作用。  相似文献   

10.
60Co γ射线对肝癌细胞株HepG2增殖和细胞周期的影响   总被引:1,自引:1,他引:0       下载免费PDF全文
目的观察^60Coγ射线对肝癌细胞株HepG2增殖、凋亡和细胞周期的影响,并探讨γ射线对细胞周期改变与p27^kip1蛋白表达和分布之间的关系。方法以不同剂量的γ射线照射培养的HepG2细胞,观察细胞形态和生长曲线变化,同时应用流式细胞计数仪观察细胞周期和凋亡的改变,并应用免疫荧光方法观察p27^dip1蛋白的表达和分布改变。结果^60Coγ射线照射细胞引起HepG2细胞株剂量依赖性的生长抑制和凋亡增加。^60Coγ射线可引起细胞G2/M期阻滞,同时p27^kip1表达明显抑制,并主要分布于细胞浆。结论^60Coγ射线所导致的肝癌细胞株HepG2细胞的G2/M阻滞可能与细胞内D27^kip1“pl的表达抑制和细胞浆的分布比例增加有关。  相似文献   

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The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.  相似文献   

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Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas (CCF) and their complications such as pseudoaneurysms. Methods: Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% (4/22). A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% (8/22). Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.  相似文献   

15.
Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.  相似文献   

16.
Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).  相似文献   

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KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief,intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.,≥90%of VO2 peak).  相似文献   

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In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex® ESI 16 (European Standard Investigator 16) and the PowerPlex® ESI 17 Systems. The PowerPlex® ESI 16 System combines the 11 loci compatible with the UK National DNA Database®, contained within the AmpFlSTR® SGM Plus® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR® SGM Plus® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex® ESI 17 System amplifies the same loci as the PowerPlex® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR® SGM Plus® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.  相似文献   

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