Association of the Platelet Glycoprotein Ⅰa C807T Gene Polymorphism With Risk of Myocardial Infarction in Chinese

Objectives To investigate the relationship of the GPIa C807T dimorphism to the risk of myocardial infarction (MI) in Chinese. Methods We did a case-control study including 100 patients and 110 controls with same race. An allele-specific polymerase chain reaction (PCR) was used for genotyping of C807T polymorphism. Results An apparent association was found between the T807 allele and MI among individuals younger than the mean age of 60 years (odds ratio,2.49; 95% confidence interval, 1.08 ～ 6.22 ). The T807 allele remained an independent risk factor for MI when age, sex, smoking, hypertension, diabetes, bodymass index, LDL-cholesterol and HDL-cholesterol were adjusted by logistic regression. Conclusions GPⅠa T807 appears to be an independent risk factor for MI.     

Extracellular Enzyme Activities by Basidiobolus and Conidiobolus Isolates on Solid Media./Extrazelluläre Enzymaktivitäten bei Basidiobolus- und Condiobolus-Isólaten auf festen Medien

Summary: Fifty-seven isolates of Basidiobolus from reptiles and amphibians, and 7 other obtained from the American Type Culture Collection (ATCC) in Maryland were studied for their extracellular enzyme activities on solid media. The Conidiobolus isolates studied included 4 recovered from Nigerian soil and additional 4 obtained from the ATCC All these isolates produced active extracellular lipase and protease and failed to exhibit amylase, deoxyribonuclease and ribonuclease activities. The significance of the findings is discussed.
Zusammenfassung: Fünfundsiebzig Basidiobolus-Isolate aus Reptilien und Amphibien und sieben weitere aus der American Type Culture Collection (ATCC) in Maryland wurden auf Aktivtäten extrazellulärer Enzyme auf festen Medien untersucht Die untersuchten Conidiobolus-Isolate schlossen vier aus nigerianischen Böden und vier weitere aus der ATCC ein. Alle Isolate zeigten extrazellulär Lipase- und Proteaseaktivität Amylase-, Desoxyribonuclease- und Ribonucleaseaktivität war jedoch nicht nachzuweisen. Die Bedeutung dieser Befunde wird diskutiert.     

用99Tcm-HL91评价鼠心肌缺血模型

目的 探讨乏氧心肌显像剂99Tcm-4,9-二氮-3,3,10,10-四甲基十二烷-2,11-二酮肟(HL91)用于诊断实验性缺血心肌的价值.方法 建立大鼠心肌在体缺血再灌注模型,采用体外放射自显影法检测正常对照组(6只)、缺血再灌注组(8只)及无再灌注组(8只)鼠心肌对99Tcm-HL91的摄取.结果 对照组和无再灌注组心肌未见局灶性放射性浓聚,再灌注组心肌非坏死区有较高放射性浓聚,与正常心肌组织的摄取比值为1.634±0.354.结论 99Tcm-HL91表现出较强的亲乏氧组织特性,能较好区分存活和梗死心肌.     

Comparison of 180° and 360° acquisition for myocardial perfusion SPECT with compensation for attenuation, detector response, and scatter: Monte Carlo and mathematical observer results

BACKGROUND: The optimal projection data acquisition strategy for myocardial perfusion (MP) single photon emission computed tomography (SPECT) remains controversial. METHODS: We compared MP SPECT using 180 degrees and 360 degrees projection data obtained with the same acquisition time, reconstructed either with filtered back projection (FBP) or the iterative ordered-subsets expectation maximization (OS-EM) algorithm with various combinations of attenuation, detector response, and scatter compensation using mathematical observers and a myocardial defect detection task. We used Monte Carlo-simulated projection data from a population of 3-dimensional nurbs-based cardiac-torso (NCAT) phantoms with ranges of variability in patient anatomy, organ uptake, defect location, defect size, and noise level based on clinical data. Projection data from 180 degrees and 360 degrees acquisitions were generated by assuming the same acquisition time. After iterative or FBP reconstruction, standard postprocessing methods were applied. For each acquisition and reconstruction method, we optimized the number of iterations and cut-off frequency of the Butterworth filter using the Channelized Hotelling Observer methodology. The optimum set of parameters was that which gave the maximum area under the curve. RESULTS: For both acquisition protocols, OS-EM with compensations provided better performance than FBP or OS-EM without compensation. For FBP, the optimized 180 degrees acquisition provided a statistically significant increase in AUC as compared with optimized 360 degrees acquisition. For OS-EM, the AUCs for 180 degrees were slightly larger than for 360 degrees acquisitions when comparing images reconstructed with the same compensations. However, the differences were smaller and not statistically significant. CONCLUSION: With optimized reconstruction and filtering parameters, 180 degrees acquisition provided a statistically significant improvement over 360 degrees acquisition for FBP reconstruction. However, for OS-EM the differences were small and not statistically significant.     

Evaluation of left ventricular mechanical dyssynchrony as determined by phase analysis of ECG-gated SPECT myocardial perfusion imaging in patients with left ventricular dysfunction and conduction disturbances

Background  Cardiac resynchronization therapy (CRT) is approved for the treatment of patients with advanced systolic heart failure and evidence of dyssynchrony on electrocardiograms. However, a significant percentage of patients do not demonstrate improvement with CRT. Echocardiographic techniques have been used for more accurate determination of dyssynchrony. Single photon emission computed tomography (SPECT) myocardial perfusion imaging has not previously been used to evaluate cardiac dyssynchrony. The objective of this study is to evaluate mechanical dyssynchrony as described by phase analysis of gated SPECT images in patients with left ventricular dysfunction, conduction delays, and ventricular paced rhythms. Methods and Results  A novel count-based method is used to extract regional systolic wall thickening amplitude and phase from gated SPECT images. Five indices describing the phase dispersion of the onset of mechanical contraction are determined: peak phase, phase SD, bandwidth, skewness, and kurtosis. These indices were determined in consecutive patients with left ventricular dysfunction (n=120), left bundle branch block (n=33), right bundle branch block (n=19), and ventricular paced rhythms (n=23) and were compared with normal control subjects (n=157). Phase SD, bandwidth, skewness, and kurtosis were significantly different between patients with left ventricular dysfunction, left bundle branch block, right bundle branch block, and ventricular paced rhythms and normal control subjects (all P<.001) Peak phase was significantly different between patients with right ventricular paced rhythms and normal control subjects (P=.001). Conclusions  A novel SPECT technique for describing left ventricular mechanical dyssyn-chrony has been developed and may prove useful in the evaluation of patients for CRT. This study was funded in part by a research grant from the Medtronic-Duke Strategic Alliance, of which Dr Borges-Neto is the primary investigator.     

手术治疗心肌桥15例报告

目的探讨外科手术对心肌桥的治疗效果。方法1999年1月～2006年10月,我院对15例心肌桥(13例有典型心绞痛,经正规药物治疗,症状控制不佳,1例急性心肌梗死,1例心悸、晕厥)行手术治疗,其中9例行非体外循环不停跳手术(3例单纯心肌桥切开松解术,2例单纯冠状动脉搭桥术,4例心肌桥切开松解术联合冠状动脉搭桥术),6例行体外循环下手术(5例心肌桥切开松解术联合冠状动脉搭桥术,1例单纯心肌桥切开松解术)。结果15例手术均取得成功,非体外循环不停跳手术组手术时间(2.8±1.9)h;体外循环手术组手术时间(3.5±1.7)h,体外循环时间(59±37)min。无手术死亡及手术并发症,术后3个月心绞痛、心悸症状完全缓解,11例心电图恢复正常。15例随访0.5～7年,(1.9±1.2)年,1例复发心悸,其余患者无心绞痛复发。结论外科手术治疗心肌桥具有良好的近、中期效果。     

用心肌灌注显像靶心图定量分析评价AMI患者骨髓干细胞移植术疗效

目的 探讨靶心图上心肌灌注缺损区定量分析方法的可靠性、重复性及应用价值。方法 16例急性心肌梗死（AMI）行自体骨髓单个核细胞移植治疗的住院患者，于治疗前、治疗后45和90d行^99Tc^m-MIBI静息心肌灌注显像。在靶心图上勾画缺损区（在左心室靶心图中放射性计数低于40％的区域），并进行定量分析。结果 （1）不同操作者所得ROI结果之间的差异无统计学意义（t=0．52，P〉0．05）。（2）治疗后45d心肌灌注缺损区面积较治疗前缩小34．32％，差异有统计学意义（t=2．83，P〈0．05）；治疗后90d心肌灌注缺损区面积较治疗后45d缩小14．77％，差异有统计学意义（t=2．51，P〈0．05）。示自体骨髓单个核细胞移植对缺血心肌的恢复有一定疗效，能够缩小梗死面积，且自体骨髓单个核细胞冠状动脉内移植治疗AMI的疗效在移植后早期（45d内）即有体现。（3）面积百分比是观察心肌灌注变化的重要定量指标。结论 该方法对心肌病变范围及严重程度能准确定量；对评价AMI骨髓于细胞移植术疗效有一定的价值。     

慢性阻塞性睡眠呼吸暂停低通气综合征心肌损伤肾功能不全与病情严重程度的关系

目的:探讨慢性阻塞性睡眠呼吸暂停低通气综合征(obstructive sleep apnea-hypopneasyndrome,OSAHS)患者心肌损伤、肾功能不全患病率其及与OSAHS病情严重程度的关系。方法:回顾性收集98例OSAHS患者的临床资料,并设立正常健康对照组40例,根据患者呼吸暂停低通气指数(apnea-hypopnea index,AHI)、最低血氧饱和度(SaO2m in)的水平将OSAHS患者分成轻度、中度、重度组。计算各组心肌损伤、肾功能不全患病率,探讨血清脂蛋白Lp(a)、心肌肌钙蛋白I(CTnI)及肌酐(Cr)水平的变化及与OSAHS病情严重程度的相关性。结果:OSAHS与对照组相比,Lp(a)、CTnI和Cr水平明显增高,差异有统计学意义(P<0.01);随着OSAHS病情严重程度分级的升高,血清脂蛋白(a)、心肌肌钙蛋白I及Cr浓度在升高,且三组间有统计学差别(P<0.01);OSAHS心肌损伤、肾功能不全的患病率分别为51.02%、24.48%,并且随着OSAHS病情严重程度分级的升高,心肌损伤、肾功能不全患病率也在升高。结论:随着OSAHS病情严重程度分级的升高,Lp(a)、CTnI和Cr水平在升高,心肌损伤、肾功能不全患病率也在升高,提示OSAHS患者中心肌损伤、肾功能不全较常见,Lp(a)、CTnI和Cr可以作为OSAHS病情严重程度的评价指标之一。     

EPO预处理对培养心肌细胞缺氧/复氧损伤TNF-α表达的影响及机制

目的 观察促红细胞生成素（erythropoietin，EPO）预处理对培养心肌细胞缺氧复氧前后TNF-α表达的影响，并进一步研究其可能的NF-kB信号机制。方法采用培养乳鼠心肌细胞建立缺氧复氧损伤模型，分为对照组、EPO组[缺氧复氧前24h，培养液中加入终浓度10U/ml的重组人促红素（recombinant human erythropoietin，RHuEPO）]、EPO＋吡咯烷二硫氨基甲酸盐（PDTC）组（缺氧复氧前24h，加入终浓度10U／ml的RHuEPO和5μg/ml的PDTC）和PDTC组（缺氧复氧前24h，加入终浓度5μg/ml的PDTC）。分别于缺氧复氧损伤前后，以RT-PCR和western blot检测各组心肌细胞TNF-α基因表达变化，同时以EMSA检测各组心肌细胞NF-kB活性变化。结果缺氧复氧损伤前，各组心肌细胞TNF-α基因表达水平差异无统计学意义，均较弱。损伤后各组心肌细胞TNF-α基因表达水平较损伤前对照组显著升高（P〈0．01），而EPO组TNF-α基因表达水平低于其他各组（P〈0．01）。缺氧复氧损伤前EPO组NF-kB活性高于其他各组（P〈0．01），损伤后各组NF-kB活性显著高于损伤前对照组（P〈0．01），EPO组NF-kB活性低于其他各组（P〈0．01）。结论EPO预处理抑制缺氧复氧后心肌细胞TNF-α基因表达升高，可能与缺氧复氧后NF-kB活性升高被抑制有关。EPO预处理可能通过NF-kB活化的负反馈机制抑制缺氧复氧后心肌细胞NF-kB活性的升高。     

神经肽Y对心肌蛋白质合成的影响及其意义

用~3H-亮氨酸参入法与放射免疫分析法分别测定大鼠心肌蛋白质合成速度与心脏组织中神经肽Y(NPY)含量。结果显示NPY能显著促进心肌蛋白质合成,其最大效应较去甲肾上腺素(NE)大35%,所需浓度是NE的1/100。心肌梗塞后非梗塞区组织内NPY的含量在2天时无显著改变,15天时则降低71%,提示2～15天期间该区域NPY释放增加,此为非梗塞区心肌肥大的机制之一