大鼠急性心肌缺血后心肌NF-kB的检测及其法医学意义

目的检测大鼠急性心肌缺血后核因子-kB(NF-kB)在心肌组织内的变化,探讨其在心肌早期缺血死后诊断中的法医学意义。方法30只大鼠随机分为正常对照,缺血0.5h,1h,2h,4h,8h共6组,每组5只建立大鼠急性心肌缺血模型,用免疫组化染色技术(S-P法),观察不同时间缺血心肌中NF-kB阳性着色,并应用图像分析系统进行定量分析。结果大鼠心肌缺血30m in,心肌细胞核出现散在NF-kB阳性染色;缺血60m in,心肌阳性染色细胞核增多;4h达高峰;8h组开始下降;免疫组化染色定量检则的阳性单位:缺血2h、4h、8h分别为20.042±1.084、22.028±3.452和20.524±1.595;正常对照组未见核阳性反应。结论大鼠心肌缺血8h内,心肌细胞核NF-kB阳性染色呈现一定规律性变化,对早期急性心肌缺血的死后诊断具有法医学意义。     

Cathepsin-L在缺血心肌中的表达

目的检测cathepsin-L(CTSL)在大鼠早期缺血心肌中的表达变化,并探讨其法医学意义。方法建立大鼠早期心肌缺血模型,设置早期缺血组(early ischemic myocardium,EIM)、非缺血组(non-ischemic myocardium,NIM)、假手术组以及空白对照组,采用real-time PCR方法检测大鼠缺血后15min,30min,1h和2h CTSL mRNA的表达量,并进行组内和组间比较。收集心源性猝死者缺血心肌和机械性损伤致死者正常心肌样本,采用免疫组化染色方法观察心肌组织中CTSL蛋白表达。结果 EIM组CTSL mRNA表达量与NIM组、假手术组及空白组相比,在15min时无统计学意义(P>0.05),在30min、1h和2h时分别升高1.4、3.1和4.5倍(P<0.05);其余3组间差异无统计学意义(P>0.05)。观察10例冠脉狭窄程度Ⅲ～Ⅳ级的心源性猝死(SCD)者缺血心肌,CTSL表达增强。结论大鼠心肌缺血后早期即可检测到CTSL mRNA的升高,并在SCD冠脉狭窄死者缺血心肌中高表达,提示CTSL可作为心肌缺血与SCD的参考指标。     

Recognition of Early Myocardial Infarction by Immunohistochemical Staining with Cardiac Troponin‐I and Complement C9*

Abstract: The diagnosis of early myocardial infarction (MI) after death, especially in the first few hours (c. 6 h) after the onset of MI, poses a challenge to the forensic pathologists. During this time, the damaged myocardium does not show grossly identifiable morphological changes and may not be recognized even with routine histological microscopic examination. However, the infarcted cardiac tissue releases certain chemicals that can be detected microscopically, two of these being cardiac troponin‐I (CT‐I) and complement C9 (C9). This study utilizes the importance of these two biomarkers immunohistochemically in an attempt to identify this early phase of MI. This study reveals that the early phase of MI of <6 h duration may be detected through immunohistochemical staining with CT‐I and C9. The ischemic/infarcted cardiac myofibers in the <6 h group display reduced/absent CT‐I staining as well as positive C9 staining.     

常用心脏标志物的生化检测及法医学应用

在法医病理学鉴定工作中,由早期缺血性心肌病变及致死性心律失常引起的心源性猝死常常缺乏典型的病理组织学改变,如何准确、客观地诊断、查明死因是法医病理学亟待解决的问题。近来研究发现的一些心肌特异性指标对心源性猝死的诊断有很好的应用前景。本文介绍几种常见心肌特异性标志物的生化特点、实验室检验方法以及临床和法医学应用前景,以期为心源性猝死的法医病理学鉴定提供依据。     

VEGF在家兔缺血心肌中的表达及其死后稳定性研究

目的观察心肌中VEGF在死后一定时间的稳定性及表达的变化规律，评价其对死后诊断机体早期心肌缺血的作用。方法用冠状动脉结扎法建立家兔急性心肌缺血模型，应用SP法染色、图像分析和统计学处理系统，检测缺血心肌细胞内VEGF阳性表达面积和强度，并对VEGF在死后不同时间的稳定性进行比较。结果VEGF在缺血心肌组织中，见灶性或成片心肌细胞强阳性表达，部分细胞呈阴性或弱阳性表达，血管内皮及平滑肌细胞表达弱阳性，间质表达阴性；在4℃放置，随时间延长，缺血心肌组织VEGF阳性表达有减弱趋势，至10d时缺血心肌组织仍可见VEGF在少许心肌细胞胞浆内呈弱阳性表达。在4℃放置10d以内，缺血心肌和正常心肌标本之间VEGF阳性表达具有极显著性差异。结论VEGF能耐受一定程度自溶及腐败的影响，其免疫组化检测对于判断死后4℃放置10d以内的尸体是否出现过心肌缺血具有一定意义。     

冠心病猝死心肌mcl-1蛋白检测及其意义

目的观察冠心病猝死(SCD)心肌mcl-1蛋白产物,探讨其免疫组化检测及其对SCD诊断的意义。方法运用免疫组织化学SABC法,对46例SCD和40例非猝死心肌(有冠心病和无冠心病)中mcl-1蛋白产物进行检测和观察,并比较其差异。结果(1)自症状出现至死亡,时间超过30min的SCD(36例),其心肌组织均出现mcl-1蛋白阳性染色;(2)自症状出现至死亡,时间短于30min的SCD(10例),其心肌组织mcl-1蛋白呈弱阳性染色;(3)冠心病非猝死样本(20例),4例心肌出现微弱的mcl-1蛋白阳性染色,无冠心病非猝死样本(20例)几乎没有出现阳性染色。结论心肌mcl-1蛋白的免疫组化检测可诊断自症状出现至死亡时间超过30min的SCD。     

Immunostaining by complement C9: a tool for early diagnosis of myocardial infarction and application in forensic medicine

Before the first 12 hours, diagnosis of early myocardial infarctions is always difficult for forensic pathologists. We tested complement C9 expression in 121 formalin-fixed and paraffin-embedded heart samples by an immunohistochemical procedure. The heart specimens were separated into four groups: 33 cases in group 1 with typical ischemic damages histologically located, 20 cases in group 2 with death related to myocardial infarction on the basis of ischemic presentation on electrocardiogram but no obvious histological ischemic damage, 35 cases in group 3 with severe coronary disease without cause of death found at the autopsy, and 33 cases in group 4 without sign of myocardial infarction and without coronary disease. In the first group, all 33 heart samples showed a well-defined C9 expression in the necrotic areas. The second group in 17 of 20 cases showed positive areas for C9 expression. In the other three heart specimens, only few stained cells were observed whereas the painful symptoms had begun less than 1 h before death. The third group showed C9 immunopositive areas in six of 35 cases, few stained cells in 8 cases, and no C9 deposition in the 21 other cases. The last group showed no staining area. To avoid nonspecific C9 staining due to tissue autolysis, we studied C9 expression during a controlled putrefactive process in four cases included in group 1; staining was found only in infarcted myocardial areas, and was observed up to ten days. Specificity of C9 expression was evaluated to be 100% [89.4 to 100%] and sensitivity to be 85% [62.11 to 96.79%]. In conclusion, evaluation of immunohistochemical expression of C9 appears to be a highly sensitive and specific marker of early myocardial infarction, useful in forensic medicine if survival is more than 1 h after the beginning of myocyte damage.     

IMA和H-FABP在心源性猝死法医学诊断中的应用

急性心肌缺血的发生是心源性猝死的最常见原因,而如何认定早期急性心肌缺血是法医学研究的热点,同时也是临床预防心肌梗死发生的重要环节。本文通过对缺血修饰白蛋白(ischemia modified albumin,IMA)和心型脂肪酸结合蛋白(heart-type fatty acid binding protein,H-FABP)的结构、功能、临床应用价值及法医学中的应用前景进行综述,旨在分析二者是否可作为早期心肌缺血的生化检测指标用于心源性猝死的诊断,并为今后选择心源性猝死的科研方向提供借鉴。     

急性心肌缺血再灌FOS免疫组织化学实验研究

探寻FOS蛋白在心肌早期缺血再灌流损伤中变化规律,为心性猝死的诊断提供新方法。利用SD大鼠建立心肌缺血再灌流损伤模型,设立正常、缺血对照组与缺血再灌组。心脏标本经HE染色及免疫级化观察。结果发现,在冷冻切片上缺血20min再灌流30min,再灌流区心肌细胞核呈阳性着色。但在石蜡切片上,缺血30min再灌流30min后,再灌流区才有心肌细胞核（37．76％±9．66％）呈弱阳性着色,再灌流60min后核呈棕褐色阳性染色,120min后开始减弱（35.36％±3.16％）。正常和单纯缺血组心肌细胞核未见有阳性反应。HE染色无明显病理改变。结果提示,SABC－FOS免疫组织化学方法最早可揭示心肌缺血20min再灌流30min的损伤,FOS蛋白在再灌流后60－120min之间可能有一个高峰表达。此法对显示实验性心肌早期缺血再灌流损伤有重要的价值。有望用于心性猝死的诊断。     

Study on expression of the glycoprotein in myocardial cell membrane of the rat's early myocardial ischemic

OBJECTIVE: To explore expression of the glycoprotein in early myocardial ischemic. METHODS: The glycoprotein changes occurred at the early acute cardiac ischemic area induced experimentally by ligation of left coronary artery of 32 SD rats. 6 lectins were measured by means of immunohistochemical methods. RESULTS: Positive staining of PNA could be observed in ischemic area at 5 min after ischemia, and the positive area increased with the prolongation of ischemic period. It became the strongest for 2 h and then decreased. CONCLUSION: This experiment proved that myocardial cell membrane in ischemia expressed D-galactose. This may be of some value in forensic medicine practice.     

心肌早期缺血再灌流损伤HSP70表达研究

目的　探讨早期缺血再灌流损伤心肌组织热休克蛋白 70 (HSP70 )的变化 ,为心源性猝死的法医病理学鉴定寻找新的依据。　方法　建立家兔早期心肌缺血再灌流动物模型 ,用免疫组化SABC法观察HSP70的表达。　结果　心肌缺血 15min再灌流 30min后 ,再灌流区心内膜下可见HSP70阳性表达 ;缺血30min再灌流 30min后 ,HSP70阳性反应细胞数目较多 ,散布于心肌全层 ;缺血 6 0min再灌流 30min后 ,再灌流区阳性表达明显减少 ,而其边缘见阳性表达略有增强。各实验组正常区和对照组心肌组织均未见阳性反应。　结论　心肌组织HSP70的阳性表达是一项显示心肌早期缺血再灌流损伤的灵敏指标 ,HSP70的免疫组化检测对缺血再灌流损伤所致心源性猝死的死后诊断具有一定的应用价值。     

Primary study of vascular endothelial growth factor immunohistochemical staining in the diagnosis of early acute myocardial ischemia

The expression of vascular endothelial growth factor (VEGF) in the model of rat early acute myocardial ischemia was studied by Strept-Avidin-Biotin-Peroxidase Complex (SABC) immunohistochemical staining. After ligating the anterior descending branch of the left coronary artery, an initial rapid (30min) positive expression of VEGF in myocardial ischemic areas was observed, the intensity of positive expression of VEGF increased with the continuation of myocardial ischemia. After 5h infarction, the strongly positive myocytes of SABC-VEGF staining were predominantly limited to perimyocardial infarction areas. No positive expression of VEGF was found in the control group. These findings suggested that SABC-VEGF method could give a sensitive, specific, simple and objective morphologic evidence to the diagnosis of sudden cardiac death caused by acute early myocardial ischemia.     

Immunohistochemical C5b-9-complement complex demonstration in early stages of myocardial necroses using paraffin sections

With conventional staining techniques it was nearly impossible to differentiate with certainty between early ischemic myocardial lesions, autolytic changes and intact myocardium without a nuclear section. In 1986 it was introduced an immunohistochemical method, which presented C5b-9 Complement Complex as a necrosis marker in cryostat sections. Our further development of this process has resulted in a technique for application on routine paraffin sections: C5b-9 Complement Complex is particularly well-suited for the exact and autolytically insensitive presentation of disseminated necroses of fiber bundels and single fibers of myocardium. The application of the technique on paraffin sections will lead to the use of the same in forensic medicine routine diagnostics of early ischemic myocardial lesions, even in cases of "sudden" cardiac death.     

Cytoskeleton immunohistochemical study of early ischemic myocardium

Previous studies on cytoskeletal changes of in vitro and in vivo animal models of ischemic myocardium have suggested the possibility of using alterations in cytoskeleton proteins as an early marker for the post-mortem diagnosis of myocardial ischemia in cases of sudden death due to coronary artery disease (CAD). In the present study, using the technique of ABC-immunohistochemistry, we examine the changes of three cytoskeletal proteins: vinculin, desmin and α-actinin in human myocardial samples taken from 14 cases of CAD sudden death and 13 cases of non-CAD death. Results of these examinations are compared with immunohistochemical changes of myoglobin and histochemical staining of hematoxylin and eosin and phosphotungstic acid, and Masson trichrome. Patchy and extensive loss of the three cytoskeletal proteins was demonstrated in the myocardium of victims who died 1 h or later following the onset of symptoms of ischemic myocardium. The pattern of cytoskeleton change is equivocal in the cases of CAD who died less than 1 h after the onset of symptoms and of the cases of non-CAD. In these cases, no significant histological change was observed. With less non-specific background changes and stronger positive staining, immunohistochemical staining of the three cytoskeletal proteins is more reliable than myoglobin, which has attracted the attention of many pathologists searching for anatomic evidence of ischemic myocardium in coronary artery disease.     

缺血修饰白蛋白在急性缺血性心脏病中的法医学应用

目的探讨心包液中缺血修饰白蛋白(ischemia modified albumin,IMA)水平在心脏性猝死诊断中的应用价值及法医学意义。方法应用白蛋白-钴离子结合法检测急性缺血性心脏病组(36例)、急性心肌梗死组(6例)、心肌病组(4例)、对照组(15例)死者的心包液中IMA水平,比较各组之间IMA水平的差异。通过ROC曲线获得最佳IMA水平的截断值以及区分急性缺血性心脏病和对照组的敏感度和特异度。结果急性缺血性心脏病组心包液中IMA水平高于对照组(P0.05);而与急性心肌梗死组、心肌病组心包液中IMA水平比较,差异均无统计学意义(P0.05)。应用ROC曲线分析得出识别急性心肌缺血的IMA的截断值为40.65 U/m L,其诊断急性心肌缺血的敏感度为60.0%,特异度为80.5%。结论心包液中IMA有望作为诊断急性心肌缺血的参考指标,为心脏性猝死的法医学诊断提供客观依据。     

心肌缺血再灌流损伤HSP70 mRNA原位杂交研究

目的观察家兔早期缺血再灌流损伤心肌组织热休克蛋白70 mRNA的表达变化,为心性猝死的法医病理学诊断寻找新的方法.方法建立家兔心肌缺血再灌流损伤模型,通过原位杂交技术观察研究.结果心肌缺血15min再灌流30min后,缺血区HSP70 mRNA阳性反应增强,阳性颗粒均匀散布于心肌全层,随着缺血时间的延长,阳性反应细胞数目逐渐增多,染色加深.结论HSP70 mRNA原位杂交检测可望为早期心肌缺血再灌流损伤的死后诊断提供新方法.     

大鼠急性早期心肌梗死细胞膜PNA受体表达

探测急性心肌缺血早期细胞膜PNA受体的表达特点。应用免疫组化法(S-P法)对32只SD大鼠急性心肌缺血早期不同时间心肌细胞膜凝集素受体的表达进行研究。结果发现:心肌缺血15min时,心肌局部可出现PNA染色阳性,且随着缺血时间的延长,其阳性表达面积明显增加;缺血2h;其表达水平达到高峰,呈弥漫性染色阳性,明显高于对照组;2h后,心肌缺血区域PNA受体的表达开始出现下降趋势。实验结果稳定,敏感性强,可为心肌缺血早期诊断提供客观的依据。     

实验性早期心肌缺血结蛋白的免疫组织化学研究

目的　探讨急性心肌缺血早期不同缺血时间心肌细胞内结蛋白的变化 ,为早期心肌梗死死后诊断提供新的方法。方法　建立大鼠急性心肌缺血模型 ,用免疫组织化学S -P法研究心肌细胞内结蛋白的缺失情况。结果　正常心肌细胞结蛋白呈棕褐色阳性反应 ,急性心肌缺血 15min ,结蛋白即可在缺血区心肌呈小灶性缺染 ,随缺血时间延长 ,其缺染范围逐步扩大。结论　心肌细胞结蛋白的缺失是早期心肌缺血的极为敏感的指标 ,免疫组织化学染色法检测心肌细胞结蛋白的变化可望成为早期心肌缺血死后诊断的一种有意义的手段。