PTEN的ceRNA网络调控研究进展

抑癌基因PTEN的表达水平与多系统肿瘤的发生、发展密切相关。研究发现,多种microRNA可以在转录后水平调控PTEN的表达,竞争性内源性RNA（competitive endogenous RNA,ceRNA）则能够屏蔽microRNA对PTEN mRNA的抑制或降解作用,二者共同作用形成一个精细的ceRNA调控网络,参与PTEN基因表达的转录后调控。本文主要列举目前已经被鉴定的具有功能性的PTEN相关ceRNA,并探讨ceRNA调控网络对PTEN蛋白表达水平及抑癌功能的影响。     

PTEN对巨噬细胞炎性细胞因子分泌的影响及其机制研究

目的:PTEN/PI-3K/Akt通路在LPS介导的炎症和内毒素血症中可能具有重要的调控作用,PTEN与LPS刺激引起的炎性介质增多之间的关系尚不明确.文中观察PTEN对LPS攻击所致RAW264.7细胞TNF-α分泌水平的影响并探讨其可能的机制. 方法:①以RAW264.7细胞为研究对象,第1组为对照组,第2组和第3组为PTEN抑制剂组,分别提前1h加入PTEN抑制剂200、100nmol/L,以LPS刺激6h后收集细胞培养上清,用ELISA法检测上清中TNF-α的水平.②将NF-κB-LUC质粒与pRL-CMV质粒共转染RAW264.7细胞,以LPS处理细胞6h后通过检测NF-κB反应性荧光素酶报告基因表达,观察PTEN在LPS攻击巨噬细胞时对NF-κB转录激活的影响. 结果:与正常细胞相比,抑制PTEN可使LPS诱导的TNF-α分泌减少,NF-κB活性减弱. 结论:PTEN可上调LPS诱导的巨噬细胞TNF-α分泌水平,可能是通过激活NF-κB的转录活性增加TNF-α的分泌水平,从而在内毒素所诱导的炎症反应中发挥重要的调控作用.     

阿霉素诱导人肝癌细胞株SMMC-7721凋亡及其机制

目的研究阿霉素诱导肿瘤细胞凋亡的机制。方法不同时间和不同剂量的阿霉素处理SMMC-7721细胞,以RT-PCR和Western blot法分别分析阿霉素处理后各分子的mRNA和蛋白表达的变化。结果阿霉素处理可以明显抑制细胞生长;使细胞呈明显凋亡改变;诱导多聚(ADP-核糖)聚合酶[poly(ADP-ribose)polymerase,PARP]水解;诱导caspase-3和caspase-9的转录水平上调。阿霉素处理可诱导人第10号染色体缺失的磷酸酶及张力蛋白同源的基因(phosphatase and tensin homologue deleted on chromosome10,PTEN)的转录和蛋白水平升高,可能使细胞进入凋亡过程。一旦细胞发生凋亡,PTEN转录和蛋白水平下降;随之诱导FAK转录和蛋白表达水平降低。结论阿霉素可以通过涉及caspase-3的途径诱导SMMC-7721肝癌细胞凋亡。阿霉素诱导的凋亡对PTEN、局部黏着斑激酶(focal adhesion kinase,FAK)表达及FAK磷酸化均有明显影响。     

PTEN基因在周围神经损伤修复中的作用机制研究进展

周围神经损伤是影响人类健康的重大疾病之一,由于该病损伤修复机制阐述不明,使其治疗效果不佳,也因此成为临床领域骨科医生的治疗难点。近年来,第10号染色体缺失的磷酸酶及张力蛋白同源基因(phosphatase and tensin homologue deleted on chromosome 10,PTEN)在周围神经损伤修复中研究较多,本文就PTEN基因通过调控周围神经损伤后的突触再生、炎性及免疫反应、神经元凋亡、神经营养相关因子等过程以及核因子-κB(NF-κB)、磷脂酰肌醇激酶/蛋白激酶B/雷帕霉素靶蛋白(PI3K/AKT/mTOR)、非受体酪氨酸激酶/信号传导及转录激活蛋白(Jak/stat)、丝裂原活化蛋白激酶(MAPK)等信号通路的作用影响周围神经损伤后的修复进程作一综述,为相关研究提供便利。     

抑癌基因PTEN的研究进展

第10号染色体同源缺失性磷酸酶 张力蛋白基因（Phosphatase and Tensin homolog deleted on chromosome Ten,PTEN）在多种肿瘤中存在突变。PTEN基因产物具有蛋白磷酸酶活性和脂质磷酸酶活性,其C端可调节PTEN在膜上的靶向定位。结合到质膜上的PTEN通过催化磷脂酰肌醇3,4,5-三磷酸（phosphatidylinositol 3,4,5-triphosphate,PIP3）的降解来调节细胞内PIP3水平,对PKB/AKT途径进行负调控。在细胞内,PTEN与许多细胞表面受体相互作用,对一些受体介导的信号转导途径进行负调节,从而调控细胞的增殖、迁移和侵袭。PTEN也通过与p53蛋白结合,调节基因转录,进而对细胞生长或细胞凋亡进行调控。     

线粒体转录终止因子家族的研究现状及进展

线粒体转录终止因子(Mterf)是线粒体DNA转录、翻译过程中的一种重要调控因子,主要在转录终止方面发挥相关作用,同时也可参与线粒体起始的调控。随着线粒体基因转录调控机制以及人类线粒体疾病研究的不断深入,Mterf的功能及特点等方面的研究逐渐成为一个新兴的热点,获得了一些新的发现。Mterf家族是一种多功能的蛋白家族,根据其结构特征的不同可分为4类,分别命名为Mterf1~4。     

肾移植急性排斥反应中的蛋白质组学研究初步探索

目的 探讨蛋白质组学在急性排斥反应(AR)发病机制研究中的应用.方法 应用同位素标记相对和绝对定量(iTRAQ)标记的定量蛋白质组学方法比较2008至2010年复旦大学附属中山医院肾移植术后5例发生AR和8例肾功能稳定患者的血浆蛋白谱.结果 比较两组患者血浆蛋白谱,发现了179个差异表达的蛋白;其中有66个蛋白表达差异在2倍以上.MetaCore软件分析结果显示差异蛋白主要参与炎症反应、补体激活等病程,符合AR的免疫排斥病程;并且蛋白组学结果提示AR患者存在高凝状态.转录调控网络分析发现AR中有多个转录因子包括核因子-κB、信号转录和激活因子( STAT)1、STAT3及它们之间的交联对话在AR和凝血系统激活中起到重要作用.结论 蛋白组学分析为AR的机制研究提供一种新的研究策略.     

端粒酶和PTEN在大肠癌中的研究进展

大肠癌的发生、发展受多种基因的调控,端粒酶和第10号染色体缺失的磷酸酶和张力蛋白同源物基因(PTEN)在大肠癌的发生、发展、转移及预后中起重要作用。端粒酶是一种反转录酶,它的激活能解决染色体复制缩短的问题,它的过度表达能使细胞永生化并直接导致肿瘤的形成。PTEN基因是迄今发现的唯一具有双特异性磷酸酶的抑癌基因,参与细胞生长调控、肿瘤细胞浸润、血管发生及肿瘤转移的调节。PTEN蛋白表达水平降低与大肠癌细胞分化程度、淋巴结转移、Dukes分期呈正相关,所以对端粒酶和PTEN的一些相关性研究为大肠癌的发生、发展机制的阐述奠定了基础。     

cAMP反应元件结合蛋白磷酸化参与学习记忆过程的分子机制

磷酸化是细胞信号通路中转录因子活性调控的主要机制.cAMP反应元件结合蛋白(cAMP responsive elementbinding protein,CREB)是最早证实由磷酸化调控其活性的转录因子之一,在脑内所有细胞中均有表达,定位于核内并在多种信号分子诱导下调控大量下游靶基因的表达.     

microRNA在妇科肿瘤中的研究进展

miRNA是一类广泛存在的对基因进行微调的非编码RNA小分子,约占人类基因组的3%,控制了人类约1/3的mRNA表达,通过与靶基因mRNA碱基配对引导沉默复合体(RISC)降解mRNA或抑制mRNA的翻译,从而在转录后水平调控蛋白表达,参与生命过程中一系列重要进程,包括早期胚胎发育、细胞增殖、分化、凋亡、脂肪代谢以及在基因表达调控中的作用等 [1].1993年Lee等 [2]首次在线虫中发现基因Lin-4通过转录生成的RNA调控虫体的发育过程,2000年Reinhart等 [3]又发现了另一个类似的具有转录后调节功能的小分子RNA:let-7.随后的研究发现,此类小RNA在各种生物中普遍存在,miRNA作为新的研究切入点,为功能基因组学、转录调控机制及基因治疗等研究开辟了新的途径.现将miRNA的生物学特性、生成、作用机制及与妇科肿瘤的相关性研究等作如下综述.     

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.