线粒体DNA单核苷酸多态性研究进展

线粒体不仅是能量生成的场所,还参与脂肪酸的合成及某些蛋白质的合成。线粒体基因组(mtDNA)是约1650 bp的环状分子,含有37个基因,其中24个是合成蛋白质时所需的RNA编码基因,其余的13个基因参与编码呼吸链关键性复合酶的亚单位。所以mtDNA在调节机体氧化磷酸化中起关键作用。由于线粒体中的氧化呼吸链,mtDNA的突变率高于核中DNA,并且缺乏自我修复能力,mtDNA的任何突变都会累及到基因组中的功能区域,其突变和编码线粒体蛋白的基因组DNA的突变可导致线粒体功能的异常,对机体代谢、组织功能都有影响。笔者对线粒体单核苷酸多态性的生理、病理的新进展做一综述。     

线粒体DNA与肿瘤

真核细胞除了核基因组外,还存在核外基因组,即线粒体DNA(Mitochondrial DNA,mtDNA).mtDNA几乎均是小于20 kb的闭环分子,与核基因组相比,其分子量小,缺乏组蛋白保护,易受致癌物攻击,且缺乏损伤修复系统,因此是致癌物的重要靶点[1,2].近年来,国外有关mtDNA与肿瘤关系的研究越来越多,本文就mtDNA的结构特点及其突变在肿瘤发生中的地位及作用机制作一概述.     

线粒体DNA与人类肿瘤相关性的研究进展

线粒体普遍存在于除哺乳动物成熟红细胞以外的所有真核细胞中。细胞生命活动所需能量80%是由线粒体提供的,所以它是细胞进行生物氧化和能量转换的主要场所;同时线粒体也是细胞核外唯一具有基因组,且能不依赖于核DNA (nuclear DNA nDNA)进行复制、转录和翻译的细胞器。有研究证实线粒体DNA (mitochondrial DNA,mtDNA)突变与人类衰老、神经退行性疾病、心肌病、肿瘤及糖尿病等多种疾病密切相关,近年来,mtDNA与人类肿瘤的关系越来越受到     

恶性肿瘤中的线粒体DNA突变

人类肿瘤的形成与线粒体DNA(mitochondrial DNA,mtDNA)的突变有重要关系,许多恶性肿瘤中存在mtDNA突变.mtDNA突变可以损伤氧化磷酸化的功能,增加活性氧的产生,这些又能反过来加速DNA的突变,从而促进肿瘤的发生和发展.特定的mtDNA突变可以使肿瘤细胞获得适应新微环境和处理氧化胁迫的能力,从而利于肿瘤细胞转移.mtDNA的突变与肿瘤的发生和转移相关,其可能成为一个潜在的治疗恶性肿瘤的靶点.     

线粒体DNA在肺癌中的研究

线粒体不仅作为人体的供能结构,还含有唯一的核外基因组。近年来研究表明线粒体DNA(mitochondrial DNA,mtDNA)突变与多种肿瘤相关,但其具体的意义尚不明确。而其在肺癌中的研究相对较少,随着线粒体基因组结构及表达调控研究的深入,mtDNA与肺癌发病关系的研究必将成为肿瘤病因学研究的热点,本文就mtDNA与肺癌的相关研究进展作一概述。1 mtDNA功能、结构及特点线粒体是人类的能量工厂,人体至少有90%的能量由其产生[1],除此还参与细胞凋亡、维持细胞内钙铁离子平衡及其他生命活动的信号传导。线粒体DNA是除细胞核染色体外的又     

线粒体DNA与人类肿瘤相关性的研究进展

线粒体普遍存在于除哺乳动物成熟红细胞以外的所有真核细胞中。细胞生命活动所需能量80％是由线粒体提供的，所以它是细胞进行生物氧化和能量转换的主要场所；同时线粒体也是细胞核外唯一具有基因组，且能不依赖于核DNA(moclear DNA nDNA)进行复制、转录和翻译的细胞器。有研究证实线粒体DNA(mitochondrial DNA，mtDNA)突变与人类     

线粒体DNA突变与Leber氏遗传性视神经病

人线粒体DNA(mito chondrial DNA,mtDNA)是独立于细胞核染色体外的又一基因组,虽然它仅由16569bp组成,但其表达对于维持细胞的生理功能至关重要。每个mtDNA分子编码氧化磷酸化复合物中的13个关键性亚单位及2个rRNA,22个tRNA。由于mtDNA中各基因排列紧凑,除与mtDNA复制与转录有关的一小段区域外,其它部位皆不含内含子序列。因此mtDNA中的任何突变都会累及到基因组中的重要功能区     

突变的大肠癌线粒体DNA转染NIH3T3及LST细胞的研究

日的了解大肠癌细胞株（SW480，LOVO，HT29）线粒体DNA的突变，克隆突变的大肠癌线粒体DNA（mtDNA）基因，构建pcDNA3．1（＋）-mtDNA真核表达重组体，并导人NIH3T3及LST细胞。以探讨线粒体基因突变与肿瘤发生的关系。方法提取大肠癌细胞株（SW480，LOVO,HT29）mtDNA，扩增D-LOOP区，产物用DNA自动测序法进行序列分析。利用DNA重组技术将其定向插人真核表达质粒pcDNA3．1（＋）。并用脂质体法导人NIH3T3及LST细胞。用MitoCapture Mitochondrial Apoptosis Detection Kit试剂盒染色后用流式细胞仪及荧光显微镜检测转染细胞的凋亡情况。扩增并测序分析转染细胞的D-LOOP区突变特点。结果检测出大肠癌细胞株SW480、LOVO和HT29细胞mtDNAD-LOOP分别有10、9和8个突变位点。转染前后，各组间细胞凋亡无明显变化。转染细胞的核基因组可扩增出目的基因及Neo基因。4株NIH3T3转染细胞mtDNA D-环区分别检测到9、11、8和4个突变点，并相应有3、4、3和2个多态性变化。结论转染突变的大肠癌细胞mtDNA后转染细胞的mtDNA均可发生多处的突变位点；通过转染后突变的外源性的mtDNA可以整合到核基因组内；突变的mtDNA转染LST细胞及NIH3T3细胞后。不影响转染细胞的凋亡改变；mtDNA的突变可能通过影响体细胞mtDNA的突变和通过外源性mtDNA在核内的整合从而影响癌基因或抑癌基因的表达异常，从而参与肿瘤的发生发展。     

线粒体DNA异常与细胞癌变的关系

线粒体是真核细胞中的氧化中心和动力站 ,而线粒体DNA是核外唯一的遗传物质 ,其主要功能是与核DNA的协同作用制导合成呼吸链的蛋白亚基以及控制线粒体的复制、转录和表达。又由于目前mtDNA分子生物学研究的进展[1] ,已为阐明人类退行性病变、糖尿病、衰老和恶性肿瘤等疾病的发生机制奠定了基础 ,因此线粒体已成为当今社会研究的热点之一。本文就mtDNA的结构功能及遗传学特点 ,mtDNA的损伤、突变与细胞癌变的关系及诱发癌变的可能机制等作一综述。1　mtDNA的结构功能及遗传学特点1 1　Anderson等于 1981年已测定出人mtDNA的全部序列…     

mtDNA突变研究新进展

线粒体是生物细胞体内能量储存和供给的场所,线粒体DNA（mitnchondria DNA,mtDNA）是核外惟一的遗传物质。相对于核基因,线粒体DNA的突变率高,又由于本身缺乏有效的损伤修复系统,极易发生突变受损,进而影响细胞功能,产生疾病。本文就线粒体基因组突变及与疾病的关系作一综述。     

Value of D-Dimers in patients with acute aortic dissection

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.     

Research of combined liver-kidney transplantation model in rats

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.     

BLOOD PRESSURE CHANGE WITH AGE IN SALT-SENSITIVE TEENAGERS

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.     

安心颗粒对急诊经皮冠状动脉介入术后生活质量影响的研究

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.     

The comparative studies of the influences of Urapidil and Nicardipine on sino-atrial node function, atrio-ventricular node function and hemodynamics

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.     

Expression of OPGmRNA and ODFmRNA in the patients of hip fracture due to osteoporosis

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.     

Dynamic Changes in Serum Estradiol and Progesterone levels in Patients of Premenstrual Syndrome with Adverse Flow of Liver-qi

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.     

Real-time Three-dimensional Echocardiography in Assessment of Left Ventricular and Right Ventricular Volumes

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.     

SCREENING FOR A 21-CHROMOSOME ABNORMALITY IN PREIMPLANTED EMBRYOS OF ELDERLY WOMEN

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.     

Scientific principles and rigorous processes should be followed in developing clinical guidelines for therapeutic interventions of integrative medicine

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.