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1.
目的:观察SMMC-7721细胞在接受不同剂量60Co γ射线照射后线粒体DNA非编码区是否存在特定的断裂敏感点.方法:根据人线粒体DNA非编码区的基因序列设计相应的引物序列,再通过接头介导PCR(LM-PCR)及基因扫描来检测其断裂程度和位点.结果:PCR产物电泳结果显示,接受不同剂量γ射线照射后,各剂量都有相同大小的片段.通过基因扫描的方法,发现不同照射剂量下的断裂位点位置是相同的.结果说明这些断裂敏感位点不是随机分布的.并且,位点的损伤频率也是随着剂量的增加而呈现递增趋势,随着剂量的增加还出现了新的断裂位点. 结论:SMMC-7721细胞线粒体DNA非编码区确实存在对γ射线敏感的位点.  相似文献   

2.
目的 线粒体DNA(mitochondrial DNA,mtDNA)的变化可能损害氧的利用,导致细胞的氧化和减少能量的产生,从而引起肿瘤细胞的凋亡.文中观察SMMC-7721细胞在接受不同剂量60Co γ射线照射后,线粒体DNA部分D-loop区碱基的损伤规律及特定的断裂敏感点.方法 根据人线粒体DNA非编码区的基因序列设计相应的引物序列,再通过接头介导PCR(LM-PCR)及基因扫描来检测其断裂程度、位点及规律.结果 在接受不同剂量γ射线照射后,通过ligation-mediated PCR (LM-PCR)和基因扫描检测,发现各剂量都有相同大小的片段,即存在相同的断裂位点,且这些位点并非随机分布,位点的损伤频率也随着剂量的增加而呈现递增趋势.同时,随着剂量的增加还出现了新的断裂位点,且在一定范围内出现了双链断裂.结论 线粒体DNAD-loop区在60Co照射后,产生的一系列断裂敏感位点和双链断裂及本身特有的突变位点,可能对SMMC-7721细胞辐射后的细胞凋亡起到重要作用,推测mtDNA很有可能是电离辐射易感的靶点,mtDNA的变化能够作为肿瘤细胞辐照前后损伤的一个重要指标.  相似文献   

3.
人肝癌SMMC-7721细胞株部分线粒体基因表达的研究   总被引:1,自引:0,他引:1  
目的:观察人肝癌SMMC-7721细胞株部分线粒体DNA(mtDNA)基因表达的情况.方法:根据人线粒体DNA(mtDNA)基因序列,利用primer premier 5.0生物软件设计了4对PCR引物,分别是扩增D-loop区、ND6、ATPase8-ATPase6、16sRNA基因,采用RT-PCR方法对SMMC-7721细胞线粒体DNA上D-loop区及其他3个基因的表达进行了检测,并与其在正常人肝细胞株(L02)线粒体中的表达作了比较.结果:我们发现,与正常人肝细胞株(L02)相比,在SMMC-7721细胞中,D-loop区、ND6、ATPase8-ATPase6基因表达总体是增高的,16sRNA基因表达基本不变,同时在同一基因两条链(重链和轻链)之间的表达也存在差异.结论:我们认为,由于线粒体DNA编码的多肽均是氧化磷酸化酶复合物的亚单位,这些基因表达的异常可能造成细胞对氧利用障碍,细胞能量产生减少,成为造成SMMC-7721细胞主要以糖酵解的方式提供能量的重要原因之一.  相似文献   

4.
人源肝癌细胞系中甲胎蛋白基因表达及甲基化的研究   总被引:1,自引:0,他引:1  
目的:了解不同人源肝癌细胞系甲胎蛋白(AFP)基因表达及不同区域甲基化状态,探讨肝癌发生的表达遗传学调控机制。方法:采用亚硫酸氢盐-基因组测序(bisulfite-assisted genomic sequencing,BAGS)技术,检测人源HepG2、SMMC-7721肝癌细胞系和人成纤维细胞中AFP基因启动子区及CpG岛区的甲基化水平,RT-PCR检测基因的表达,并分析相关性。结果:HepG2细胞高表达AFP,SMMC-7721细胞低表达AFP,成纤维细胞不表达AFP;在启动子区,HepG2细胞的非甲基化修饰位点发生率较高,尤其是第一个和第二个CG位点,SMMC-7721细胞的甲基化程度较之高,而成纤维细胞甲基化程度整体很高;在CpG岛区,成纤维细胞的非甲基化修饰位点发生率较高,主要是第6个和第7个CG位点,SMMC-7721、HepG2细胞的甲基化程度较之高。结论:AFP基因启动子甲基化程度与基因表达水平存在负相关,AFP基因CpG岛甲基化程度与基因是否表达有关,AFP基因启动子低甲基化可能是AFP高表达的分子机制。  相似文献   

5.
本文报道10例正常外周血淋巴细胞经不同剂量X线照射后,用荧光法测定淋巴细胞DNA的损伤情况。结果表明,随着X线剂量的增加DNA的损伤率亦逐渐增大,细胞中剩余双链DNA含量减少,说明淋巴细胞DNA损伤程度与X线剂量有关。  相似文献   

6.
目的观察不同剂量X线全身照射对西藏小型猪小肠线粒体的影响及其变化特点。方法将18头成年,健康,雄性西藏小
型猪分为6组。实验组5组,对照组1组(n=3头/组)。分别接受2,5,8,11,14Gy全身X线照射。照射后72h麻醉处死并采集小
肠组织分别检测线粒体相关基因的表达,线粒体呼吸链复合酶Ⅰ,Ⅱ,Ⅲ和Ⅳ活性,线粒体琥珀酸氧化呼吸链和NADH氧化呼吸
链的功能及观察线粒体的超微结构。结果8Gy以下剂量组的线粒体蛋白编码相关基因表达、呼吸链复合物活性及呼吸功能明
显低于对照组且随放射剂量的增加而降低;而8Gy以上剂量组,上述指标虽仍明显低于对照组,但不再随放射剂量的增加而继
续降低并维持于一较低水平。电镜下线粒体超微结构在2,5Gy时的改变主要表现为线粒体的扩张及轻微的电子密度降
低。8Gy及其后的剂量组则观察到更为明显的电子密度降低及线粒体的空泡化,嵴与线粒体外膜的连接缺失等。结论电离辐
射导致的小肠线粒体损害在一定剂量范围内(8Gy以下)随放射剂量的增加而愈发明显;但接受更高强度的照射后,其损伤程度
并不会随放射剂量的增加而继续增加。
  相似文献   

7.
丹皮酚诱导人肝癌SMMC-7721细胞凋亡及其机制探讨   总被引:4,自引:0,他引:4  
目的:探讨丹皮酚诱导人肝癌细胞株SMMC-7721的凋亡作用及其分子机制。方法:噻唑蓝(MTT)法检测丹皮酚的增殖抑制作用;Hoechst-33258染色法、DNA凝胶电泳法检测细胞凋亡;逆转录聚合酶联反应(RT-PCR)法检测抑癌基因PTEN、致癌基因Akt mRNA表达水平。结果:丹皮酚在3.13~200.00 mg.L-1剂量之间均能抑制SMMC-7721的增殖;丹皮酚处理SMMC-7721后,光镜下可见明显的凋亡细胞;Hoches-33258染色、DNA凝胶电泳显示出典型的凋亡特征;RT-PCR检测示丹皮酚可使PTEN mRNA表达升高,Akt1、Akt2 mRNA表达下降。结论:丹皮酚能显著抑制SMMC-7721增殖,诱导细胞凋亡,其作用可能是通过抑制PI3K通路来实现的。  相似文献   

8.
目的研究RPB5调节蛋白RMP在γ射线诱导的SMMC-7721肝癌细胞凋亡过程中的表达,探讨RMP在细胞凋亡及维系细胞DNA稳定性中的作用。方法不同剂量60Coγ射线照射SMMC-7721肝癌细胞和HL-7702正常肝细胞,观察细胞形态变化;PI染色观察细胞凋亡;流式细胞技术检测肝癌细胞周期变化及细胞凋亡;半定量RT-PCR法检测RMP基因在肝癌细胞及正常肝细胞中的表达以及凋亡相关基因bax、bcl-2在肝癌细胞中的表达。结果随着照射剂量增加,肝癌细胞形态发生明显改变;PI染色观察细胞凋亡增多;流式细胞仪检测结果显示随着照射剂量增加,细胞凋亡明显增多,差异有统计学意义(P〈0.05),细胞周期G1期增高,而S期降低,差异有统计学意义(P〈0.05);RMP基因相对表达量增加,bax/bcl-2增加,与未照射组相比,差异有统计学意义(P〈0.05)。结论γ射线照射可诱导人肝癌细胞凋亡,RMP基因可能在提高细胞DNA稳定性中起重要作用。  相似文献   

9.
目的 探讨丙型肝炎病毒核心蛋白是否通过对Wnt信号抑制因子SFRPs的甲基化修饰,从而活化Wnt信号通路.方法 将编码HCV核心蛋白的腺病毒(AdCore)或GFP对照腺病毒(AdGFP)感染SMMC-7721细胞,采用逆转录PCR(RT-PCR)方法检测SFRPs基因mRNA的表达;用5-氮杂-2′-脱氧胞苷(DAC)对AdCore或AdGFP腺病毒感染的SMMC-7721细胞进行去甲基化处理,进一步采用甲基化特异性PCR (MSP)和DNA甲基化测序,检测SFRPs基因启动子区CpG岛的甲基化程度,Western blot检测甲基化转移酶Dnmts的表达.结果 在HCV核心蛋白过表达的SMMC-7721细胞系中,SFRP2和SFRP5基因mRNA的表达量与对照组相比明显降低(P<0.05);甲基化分析结果表明:SFRP5基因启动子区CpG岛呈现高甲基化修饰;甲基化转移酶Dnmt1、Dnmt3a表达量增加(P<0.05).结论 HCV核心蛋白可以促进SFRP5基因启动子区CpG岛的甲基化修饰,参与HCV相关疾病的发生.  相似文献   

10.
目的:通过沉默fbxl20基因,以观察基因沉默后对SMMC-7721细胞的增殖、迁移和周期分布的影响.方法:通过脂质体Lipofectamine2000介导转染SMMC-7721细胞,靶向fbxl20基因的siRNA片段阻低肝癌SMMC-7721细胞株fbx120 mR-NA表达.结果:siRNA能有效沉默SMMC-7721细胞fbx120 mRNA的表达,沉默效率为71.49%.MTT试验实验显示:siRNA转染SMMC-7721细胞后,细胞增殖能力显著降低.Transwell小室和划痕愈合实验表明,fbxl20基因被沉默后,SMMC-7721细胞在迁移能力明显减弱,迁移抑制率高达62.03%.流式细胞术检测细胞周期结果显示:转染48 h后,SMMC-7721实验组细胞G1/G0期比率(81.21%)显著高于阴性对照组(71.49%)和空白对照组(67.90%).结论:本实验运用RNA干扰技术成功抑制了SMMC-7721细胞中fbxl20基因的表达,并且发现fbxl20基因可能与肝癌细胞的增值和迁移相关.  相似文献   

11.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

12.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

13.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

14.
目的:评价使用安心颗粒对急诊经皮冠状动脉介入术(PPCI)术后生活质量的影响.方法:将160例接受PPCI的急性ST段抬高型心肌梗死患者随机分为安心颗粒组(术前顿服安心颗粒8.8g,术后安心颗粒4.4 g/次,每日2次)和对照组(仅接受基础药物治疗).所有患者均服用阿司匹林、氯吡格雷和阿托伐他汀.分别在入院时、出院前1d、出院后180 d时,应用心肌梗死多维度量表(MIDAS)、中文版SF-36评价量表对患者生活质量评分.并观察术后30 d以内的出血并发症、血小板减少症发生情况.结果:入院时和出院前1d,两组患者的心肌梗死MIDAS、SF-36量表评分比较无差异(P>0.05);出院后180 d时,与对照组比较,安心颗粒组MIDAS、SF-36评分明显减低(P<0.05);组内与入院时比较,两组出院前1d、出院后180 d时,MIDAS、SF-36评分均降低(P<0.05).两组患者在随访期间均无大量出血、少量出血、重度和极重度血小板减少症发生,安心颗粒组有4例、对照组有7例发生不明显出血(P>0.05).两组发生轻度血小板减少症的患者数比较无差异(P>0.05).结论:PPCI使用安心颗粒,能改善急性ST段抬高型心肌梗死患者的生活质量,且不增加出血风险.  相似文献   

15.
Objective:To investigate the influences of urapidil and nicardipine on rabbit sinus function,atrio-ventricular node function and hemodynamics.Methods:Thirty-two Angora's rabbits were selected and randomly divided into four groups.U1 group:urapidil 0.25 mg/kg;U2 group:urapidil 0.5 mg/kg;N1 group:nicardipine 10 μg/kg;N2 group:nicardipine 20 μg/kg.All these medicine were administrated within 30 seconds.Measurements were taken before and after the administration of urapidil or nicardipine for the following data:mean blood pressure(MAP),heart rate(HR),sino-atrial conduction time(SACT),maximal sinoatrial recovery time(SNRTmax)corrected sinus node recovery time(CSNRT),index of sinus node recovery time(SNRTI),Wenckebach A-V conduction frequency (WB),and P-R interval.Results:Significant MAP and HR changes were identified in all of the four groups before and after administration of both urapidil and nicardipine.No significant changes could be found in the rest of the parameters.Intergroup analysis showed that SACT and CSNRT of N1 and N2 groups were shorter than those of the U2 group(P<0.01);the MAP decreased(P<0.01)and the HR increased drastically(P<0.01).Conclusions:Neither urapidil(0.25 mg/kg,0.5 mg/kg)nor nicardipine(10μg/kg,20μg/kg)has any significant influence on rabbit sinus function or rabbit atrio-ventricular node function.Nicardipine could be a better choice than urapidil for parafunctional sinus node patients.  相似文献   

16.
Objective:To investigate the gene expression of osteoprotegerin(OPG) and osteoclast differentiation factor(ODF) in the bone tissue of patients with hip fracture due to osteoporosis. Methods:OPGmRNA and ODFmRNA in the bone tissue in 50 cases of osteoporosis sufferers(over 50 years old) with hip fracture(Observer Group) and 30 cases of hip facture sufferers with no osteoporosis(Control group) were analyzed with the Semi-Quantitative RT-PCR method. Results:The mRNA expressed of ODF, OPG were both high in the patients with hip fracture. In the control group, the expression of OPG mRNA was observed, while the expression of ODF mRNA was very slight. Conclusion:Aged patients contained all signals including OPG, ODF that are essential for inducing osteoclastogenesis and promoting bone resorption.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

19.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

20.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

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