Contribution of cardiac MRI in the etiologic diagnosis of chest pain syndrome with a normal angiographic aspect of the coronary arteries

The etiologic diagnosis of chest pain with elevation of specific cardiac enzymes, repolarization abnormalities and a normal angiographic aspect of the coronary arteries is difficult. In this situation, the role of cardiac MRI is growing, frequently allowing to precise the etiology of the chest pain. We present a literature review concerning the semiology of the cardiac MRI in the three main involved etiologies: myocarditis, takotsubo syndrome, and myocardial ischemia with a normal angiographic aspect of the coronary arteries.     

鼠胚胎干细胞早期分化来源的心肌细胞同种异体移植后的电生理特性

目的 探讨小鼠胚胎干细胞早期分化来源的心肌细胞进行同种异体移植后的电生理特性.方法 首先通过电转染构建a-MHC-EGFP-ESc系[将心肌细胞特异的OL-MHC启动子与表达基因--绿色荧光蛋白(EGFP)基因融合,构建成真核表达载体],悬滴法诱导胚胎干细胞分化,在分化早期(7+4)d利用流式细胞仪筛选带绿色荧光的心肌细胞,将纯化的心肌细胞(5×106个/ml)移植到小鼠心室壁,对照组注入等体积培养基,移植前3 d开始应用环孢素A(静脉注射,5 mg·kg-1·d-1)和泼尼松龙(静脉注射,2.5 mg·kg-1·d-1)抑制免疫排斥反应.移植后2周分离两侧颈迷走神经行电刺激抑制窦房结与房室结,记录刺激前后的体表心电图,然后分别行免疫荧光显像和膜片钳研究.结果 刺激迷走神经前,移植组和对照组均呈正常的窦性心律,两组无室性心律失常的发生;刺激迷走神经后,两组动物均出现异位的心室起搏心律,细胞移植组与对照组心室频率无差异.移植区冰冻切片免疫荧光分析可见EGFP标记的移植细胞具有肌钙蛋白I(cTnI)表达,说明分化细胞移植后仍具有心肌特性,且移植细胞与宿主心肌细胞间有连接蛋白43的表达,表明移植细胞与宿主心肌细胞间形成电偶联通道.膜片钳分析,绿色荧光细胞移植前后其具有起搏细胞动作电位的比例分别为(85.1%vs 1 1.4%,P＜0.05),该类细胞在移植前后的起搏电流强度有所增强((11.2±2.4)pA/pF vs(15.5±1.9)pA/pF,P＜0.05].移植区分离的绿色荧光细胞中48%具有心室肌动作电位.结论 胚胎干细胞早期分化来源的心肌细胞在体移植后能进一步分化为成熟的心室肌细胞及起搏细胞.     

比索洛尔对高血压大鼠心肌成纤维细胞增殖及胶原合成的影响

目的:探讨比索洛尔对培养的高血压大鼠（SHR）和W istar大鼠心脏成纤维细胞（CFs）增殖及胶原合成的影响。方法:采用胰酶消化法培养CFs,采用3H-胸腺嘧啶核苷（3H-TdR）掺入法测定CFs的DNA合成功能,四氮唑蓝（MTT）比色法测定细胞增殖,3H-脯氨酸（3H-Proline）掺入法测定胶原合成。结果:①基础状态下,SHR组CFs的3H-Proline掺入量3、H-TdR掺入量及MTT比色法A值均明显高于W istar组。②不同浓度比索洛尔对两组大鼠CFs3H-TdR掺入量及MTT比色法A值均无明显作用。③不同浓度比索洛尔以浓度依赖的方式抑制CFs3H-Proline掺入量,与W istar大鼠组相比,SHR组CFs受抑制的效应更强。结论:SHR的CFs细胞数目、DNA合成及胶原含量均存在异常,比索洛尔呈浓度依赖性抑制CFs的胶原合成,但对CFs增殖及DNA合成无明显作用。     

体外培养高糖、高脂喂养大鼠主动脉平滑肌细胞钙化的研究

目的 检测高糖、高脂喂养Goto-Kakizaki（GK）糖尿病大鼠主动脉平滑肌细胞（SMCs）的血管钙化指标,探讨糖尿病血管钙化的相关机制.方法 高糖、高脂喂养GK及Wistar大鼠2周,同时分离培养两组大鼠的主动脉SMCs,Wistar大鼠SMCs作为对照.通过细胞计数法观察细胞生长状况,以甲基百里香酚蓝比色法测定两组大鼠细胞层及培养上清中钙的含量,实时定量PCR检测两组细胞碱性磷酸酶（ALP）、骨桥蛋白（OPN）、核心结合因子α-1（Cbfα-1）、α-平滑肌肌动蛋白（α-SMA）的基因表达.结果 与Wistar大鼠SMCs相比,GK大鼠SMCs生长速度明显缓慢（F =363.392,P＜0.05）;细胞层钙含量[（0.56±0.22） vs.（0.39±0.09）,t=2.47,P＜0.05]明显增加,培养上清中钙含量[（0.82±0.22）vs.（1.20±0.17）,t=-22.573,P＜0.05]明显减少.GK大鼠SMCs中ALP （t=12.963,P＜0.05）、OPN（t=8.305,P＜0.05）及Cbfα-1（t=10.109,P＜0.05）的基因表达增加,同时α-SMA（t=-8.219,P＜ 0.05）的基因表达减少.结论 高糖、高脂喂养的GK糖尿病大鼠的主动脉平滑肌细胞易发生钙化.     

Mandatory criteria for cardiac rehabilitation programs: 2018 guidelines from the Portuguese Society of Cardiology

Cardiac rehabilitation (CR) is a multidisciplinary process for patients recovering after an acute cardiac event or with chronic cardiovascular disease that reduces mortality and morbidity and improves quality of life. It is considered a cost-effective intervention and is expressly indicated in the guidelines of the major medical societies.In Portugal, only 8% of patients discharged from hospital after myocardial infarction are included in CR programs. In Europe overall, the percentage admitted to CR programs is 30%, while in the USA it is 20-30%.In view of the underuse of CR in Portugal, we call the attention of the health authorities to the need to increase the number and national coverage of CR programs, while maintaining high quality standards. The aim is for all patients resident in Portugal who are eligible for CR programs to have the same opportunities for access and attendance.In order to preserve the benefits and safety of this intervention, CR needs to be performed according to international guidelines. The fact that various initiatives in this field have been developed by different professional groups, some of them non-medical, that do not follow the European guidelines, has prompted us to prepare a series of norms defining mandatory criteria for CR, based on current knowledge and evidence. In this way we aim to ensure that the required increase in the number of CR programs, linked in a national network of CR centers, does not detract from the need to maintain their efficacy and quality. These criteria should serve as the basis for the future accreditation of CR centers in Portugal.