耐力训练对大鼠心肌JAKs和SOCSs表达的影响

目的:观察耐力训练大鼠心肌JAKs和SOCSs家族成员的表达,探讨耐力训练后JAK/STAT信号通路在心肌调节中的作用。方法:雄性SD大鼠进行10周递增负荷跑台训练后,采用免疫组化法观察末次运动后即刻和24小时心肌JAK1、JAK2、JAK3和SOCS1、SOCS2、SOCS6表达,计算阳性细胞率。结果:耐力训练大鼠运动后即刻心肌JAK1阳性细胞率显著高于运动后24小时组和安静对照组(P<0.01,P<0.05),JAK2阳性细胞率无论在运动后即刻还是运动后24小时均显著高于安静对照组(P<0.05,P<0.01),而JAK3阳性细胞率与安静对照组差异无统计学意义(P>0.05)。耐力训练大鼠心肌SOCS1阳性细胞率在运动后即刻和运动后24小时均较安静对照组显著升高(P<0.01,P<0.05),SOCS2阳性细胞率也较安静对照组显著升高(P<0.05,P<0.05),而SOCS6阳性细胞率与安静对照组差异无统计学意义(P>0.05)。结论:耐力训练诱发大鼠心肌JAK1、JAK2与JAK3表达变化趋势不同,JAK1、JAK2表达升高可能影响JAK/STAT信号通路对耐力训练大鼠心肌功能和形态的调节;而耐力训练后SOCS1、SOCS2表达显著升高提示其对心肌JAK/STAT信号通路的内源性负性调节作用加强。     

超声心动图评价心梗患者非梗塞区心肌功能变化的临床研究

目的:采用组织多谱勒成像(TDI)、彩色室壁运动分析(CK)及声学密度测定(AD)评价心梗患者非梗塞区心肌功能的改变.材料和方法:前壁心梗患者合并心衰组20例,无心衰组36例,对照组23例;应用TDI、CK、AD技术分别测定后间隔基底部收缩期Sa波,舒张早期Ea波,晚期Aa波,全收缩期位移幅度和速度(CKd、CKv),及标化的背向散射积分(IBS)及其周期变化率(CVIB).结果:与对照组相比,非心衰组CKd、CKv、Ea、CVIB减低,而心衰组CKd、CKv、Sa 、Ea、Aa、CVIB均明显减低,IBS增高(P<0.05),其中CKd、CKv、CVIB与左室整体收缩功能(LVEF)有较好的相关性,CVIB与 CKd、CKv及Ea呈正相关(P<0.01).结论:TDI、CK、AD可反映非梗塞区心肌功能随LVEF的不同而出现不同程度的改变.     

中药复方对尾吊大鼠心肌ATP酶、SDH和能荷值的影响

目的观察中药复方对短期模拟失重 (尾吊 )大鼠心肌ATP酶、SDH和能荷值的影响。方法大鼠分对照组、尾吊组和中药组 (中药 +尾吊 ) ,每组 1 0只。尾吊 5d后 ,3组大鼠同时处死 ,取心肌测ATP酶和SDH ,酶不同染色处理并定量测其光密度 (OD) ,测心肌能荷值定量表示能量储备。结果尾吊组心肌细胞SDH染色比中药、对照组增强 ,OD值升高 ,ATP酶明显增强和OD值显著升高 ,心肌能荷值减少 ,其顺序为尾吊组 >对照组 >中药组。结论中药组在尾吊时由于中药复方发挥了镇静、安神、活血化瘀等药理作用 ,使大鼠心肌SDH活性减弱 ,ATP酶活性明显降低 ,能耗减少     

Fractional encoding of harmonic motions in MR elastography.

In MR elastography (MRE) shear waves are magnetically encoded by bipolar gradients that usually oscillate with the same frequency fv as the mechanical vibration. As a result, both the repetition time (TR) and echo time (TE) of such an MRE sequence are greater than the vibration period 1/fv. This causes long acquisition times and considerable signal dephasing in tissue with short transverse relaxation times. Here we propose a reverse concept with TR相似文献   

Evaluation of myocardial viability following acute myocardial infarctic using201Tl SPECT after thallium-glucose-insulin infusion —Comparison with18F-FDG positron emission tomography—

OBJECTIVE AND METHODS: The aim of this study was to evaluate myocardial viability in patients after acute myocardial infarction (AMI). We compared 201Tl SPECT after 201Tl with GIK (10% glucose 250 ml, insulin 5 U and KCl 10 mEq) infusion (GIK-201Tl) with resting 201Tl and 99mTc-pyrophosphate (PYP) dual SPECT, positron emission computed tomography (PET) using 18F-fluorodeoxyglucose (18F-FDG) in 21 patients with their first AMI, who all underwent successful reperfusion. GIK-201Tl SPECT, 201Tl and 99mTc-PYP dual SPECT were done within 10 days after admission and 18F-FDG-PET was performed at 3 weeks. GIK-201Tl SPECT was obtained after 30 min of GIK-201Tl infusion. 18F-FDG (370 MBq) was injected intravenously after oral glucose (1 g/ kg) loading, and then PET was obtained. PET and SPECT images were divided into 20 segments. Regional tracer uptake was scored using a 4-point scoring system (3 = normal to 0 = defect), and summed to a regional uptake score (RUS). Regional area means the infarcted area in which 99mTc-PYP accumulated. The number of decreased uptake segments (ES) was then determined. The infarcted area was defined as the area of 99mTc-PYP uptake. RESULTS: The ESs for the GIK-201Tl and 18F-FDG-PET images were significantly lower than the number of 99mTc-PYP uptake segments. The RUS for GIK-201Tl was higher than that for resting-201Tl imaging and similar to those for 18F-FDG-PET. CONCLUSIONS: In the detection of myocardial viability following AMI, GIK-201Tl imaging is useful with findings similar to those of 18F-FDG-PET.     

特发性肺动脉高压与先天性心脏病相关肺动脉高压患者右心室心肌葡萄糖代谢的比较研究

目的 比较分析特发性肺动脉高压（IPAH）与先天性心脏病相关肺动脉高压（PAH-CHD）患者右心室心肌葡萄糖代谢的差异。 方法 选取2016年11月至2018年12月在中国医学科学院北京协和医学院阜外医院确诊的26例IPAH患者（IPAH组）[女性17例、男性9例,年龄（28.23±8.92）岁] 和16例PAH-CHD患者（PAH-CHD组） [女性10例、男性6例,年龄（29.19±10.62）岁]。所有患者均行动态18F-FDG PET心肌代谢显像,根据Patlak法计算得出右心室和左心室心肌葡萄糖利用率（rMGU）。显像后1周内患者接受右心导管检查,测定血流动力学指标。采用独立样本t检验比较2组的rMGU等指标;采用Pearson相关分析对2组患者右心室的rMGU与平均肺动脉压力（mPAP）或肺血管阻力的相关性进行分析。 结果 IPAH组与PAH-CHD组患者mPAP之间的差异无统计学意义 [（59.85±16.46） mm Hg 对（69.75±18.93） mm Hg,t=1.79,P=0.81]（1 mm Hg=0.133 kPa）。动态18F-FDG PET心肌代谢显像测得的2组患者右心室rMGU[（0.095±0.074） μmol·g−1·min−1 对（0.135±0.165） μmol·g−1·min−1]与左心室rMGU[（0.057±0.065） μmol·g−1·min−1 对（0.070±0.047） μmol·g−1·min−1] 之间的差异均无统计学意义（t=1.07, P=0.29;t=0.77,P=0.49）。IPAH组患者右心室的rMGU与mPAP存在正相关（r=0.420,P=0.033）,但PAH-CHD组患者右心室的rMGU与mPAP无相关性（r=0.016,P=0.953）。 结论 mPAP无差异的IPAH和 PAH-CHD患者右心室心肌葡萄糖代谢水平无明显差异。     

Clinical Importance of Myocardial T2 Mapping and Texture Analysis

Late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) is valuable for diagnosis and assessment of the severity of various myocardial diseases owing to its potential to visualize myocardial scars. T₁ mapping is complementary to LGE because it can quantify the degree of myocardial fibrosis or edema. As such, T₁-weighted imaging techniques, including LGE using an inversion recovery sequence, contribute to cardiac MRI. T₂-weighted imaging is widely used to characterize the tissue of many organs. T₂-weighted imaging is used in cardiac MRI to identify myocardial edema related to chest pain, acute myocardial diseases, or severe myocardial injuries. However, it is difficult to determine the presence and extent of myocardial edema because of the low contrast between normal and diseased myocardium and image artifacts of T₂-weighted images and the lack of an established method to quantify the images. T₂ mapping quantifies myocardial T₂ values and help identify myocardial edema. The T₂ values are significantly related to the clinical symptoms or severity of nonischemic cardiomyopathy. Texture analysis is a postprocessing method to quantify tissue alterations that are reflected in the T₂-weighted images. Texture analysis provides a variety of parameters, such as skewness, entropy, and grey-scale non-uniformity, without the need for additional sequences. The abnormal signal intensity on T₂-weighted images or T₂ values may correspond to not only myocardial edema but also other tissue alterations. In this review, the techniques of cardiac T₂ mapping and texture analysis and their clinical relevance are described.     

人胚胎心肌组织发育过程中Cx43和Bcl-2蛋白表达的研究

目的观察连接蛋白43(Cx43)和Bcl-2蛋白在人胚胎心室肌组织中的表达,探讨其与心脏发育的关系。方法应用免疫组织化学法检测第2、3、4三个月胎龄段Cx43和Bcl-2蛋白在人胚胎心室肌组织中的表达。结果第2月胚龄时,人胚心室肌组织内可见单个散在分布的Bcl-2阳性细胞,随着胎龄的增加,Bcl-2阳性细胞数量逐渐增多,到第4月胎龄时,在心室肌组织内可见三五成群分布的Bcl-2阳性细胞。第2月胚龄时,Cx43蛋白呈斑点状散在分布于心室肌细胞的细胞质,随着胎龄的增加,其分布范围逐渐扩大,在心室肌细胞与心室肌细胞连接处也出现Cx43蛋白的阳性表达,到第4月胎龄时,Cx43蛋白在心室壁内逐渐形成成片弥散样分布。结论Cx43和Bcl-2蛋白参与了人胚胎早期心室肌组织细胞的生长发育。     

门控断层显像在心肌灌注断层显像中的应用

使用门控心肌断层显像不但减低了心脏搏动产生的图像边缘模糊,提高了对心肌缺血诊断的灵敏度和特异性,而且通过傅立叶变换和图像边缘识别技术等图像处理技术,可以在一次采集的信息基础上同时获得心脏的心肌血流灌注、心肌活力、室壁运动、射血功能和收缩协调性等参数,提高了核素心脏检查的价值,为临床准确判断患者的心脏状况,选择治疗方案,预后及疗效评价提供了更可靠的数据。本文就其近年来的临床应用进行综述。     

Localization and function of myocardial lipolysis

Summary Mobilization of triacylglycerol stored in heart cells is accomplished by the combined action of lysosomal (acid) lipase and microsomal monoacylglycerol lipase or carboxylesterase. Non(heparin)-releasable neutral or alkaline lipase is similar to non(readily)-releasable lipoprotein lipase (LPL). The enzyme is mainly localized extracellularly. Non(readily)-releasable LPL probably represents LPL in caveola or vacuolae of vascular endothelium and/or LPL on myocardial interstitium. It contributes to the uptake of lipoprotein constituents in heart cells. Glycerol, an endproduct of lipolysis, is not a reliable marker for the net mobilization of lipid stored in heart cells. It is formed both intra- and extracellularly, and does not reflect the rate of oxidation of part of free fatty acids formed.