Immunocytochemical diagnosis of early myocardial ischaemic/hypoxic damage

The sensitive and reliable dinitrophenyl (DNP) hapten sandwich staining (DHSS) procedure (B. Jasani et al., Virchows Arch (Pathol. Anat.), 406 (1985) 441-448) was used to study the distribution of immunoperoxidase staining seen with antibodies to seven protein markers in post-mortem heart tissue. This was obtained from 12 cases with macroscopic myocardial infarction and 17 cases without myocardial infarction (10 with and 7 without significant coronary artery atherosclerosis). The immunostaining patterns were compared with the appearances seen in adjacent sections stained by the routine haematoxylin and eosin (H & E) and phosphotungstic acid haematoxylin (PTAH) methods and a method previously recommended for the detection of early myocardial infarction, the haematoxylin basic fuchsin picric acid (HBFP) stain. Loss of immunostaining with an antibody to myoglobin was found to be a reliable and more objective marker of both early and established myocardial infarction compared with the histological stains. Antibodies to myosin, caeruloplasmin, C-reactive protein and pre-albumin gave similar but less reliable results, whilst those to complement factor C3b and alpha-1 anti-trypsin gave the least reliable results for early myocardial ischaemic/hypoxic damage. The immunocytochemical results are considered sufficiently encouraging to extend the work to a large number of sudden death cases in order to establish a new, more reliable approach to the detection of histologically latent ischaemic/hypoxic damage in the myocardium.     

抗肌动蛋白单克隆抗体在早期心肌缺血诊断中的应用

应用抗肌动蛋白单克隆抗体（HHF35），对10例正常心肌、6例已知心肌梗死、18例可疑早期心肌缺血组织进行石蜡切片免疫组化染色。结果：正常心肌阳性，梗死心肌阴性，18例可疑病例中14例呈不同程度弱阳性或阴性。表明心肌发生了缺血性改变，对比清晰，特异性强，对心肌缺血诊断有明显的应用价值。     

结蛋白诊断早期心肌梗死的特异性研究

目的　探讨结蛋白在早期心肌梗死死后诊断的特异性。方法　应用免疫组织化学S -P法检测梗死心肌和其他非梗死性的直接或间接心肌损害的心肌结蛋白染色的变化。结果梗死心肌均可见不同程度的结蛋白缺染 ,其他非梗死性的直接或间接心肌损害的心肌中 ,如心脏挫伤、心肌炎、出血性休克、电击死、机械性窒息、有机磷中毒等 ,也有不同程度的结蛋白缺染。结论　应用结蛋白免疫组织化学方法诊断早期心肌梗死需慎重     

肌红蛋白诊断早期心肌梗死的特异性研究

目的　探讨肌红蛋白在早期心肌梗死死后诊断的特异性。方法　应用免疫组织化学S -P法检测梗死心肌和其它非梗死性的直接或间接心肌损害的心肌肌红蛋白染色的变化。结果　梗死心肌均可见不同程度的肌红蛋白缺染 ,其它非梗死性的直接或间接心肌损害的心肌中 ,如心脏挫伤、心肌炎、出血性休克、电击死、机械性窒息、有机磷中毒等 ,也有不同程度的肌红蛋白缺染。结论　应用肌红蛋白免疫组织化学方法诊断早期心肌梗死需慎重     

结蛋白诊断早期心肌梗死的特异性研究

目的 探讨结蛋白在早期心肌梗死死后诊断的特异性。方法 应用免疫组织化学Ｓ－Ｐ法检测梗死心肌和其他非梗死性的直接或间接心肌损害的心肌结蛋白染色的变化。结果 梗死心肌均可见不同程度的结蛋白缺染,其他非梗死性的直接或间接心肌损害的心肿,如心脏挫伤、心肌炎、出血性休克、电击死、机械性窒息、有机磷中毒等,也有不同程度的结蛋白缺染。 结论 应用结蛋白免疫组织化学方法诊断早期心肌梗死需慎重。     

Giant cell myocarditis with cardiac tamponade: a rare combination

Giant cell myocarditis (GCM) is a rare but fatal disease of idiopathic origin. It results in focal necrosis of myocardium. This is a case report of middle aged Malaysian Indian female who died due to cardiac tamponade due to rupture myocardium and tear in the root of aorta. On naked eye examination, it simply resembled as recent as well as old fibrotic areas of myocardial infarction. She was clinically diagnosed as a case of obstructive cardiomyopathy with atrioventricular block, and was on pace maker. There was subendocardial fibrosis and left ventricular transmural infarction in the left ventricle. On histopathology, this was diagnosed as GCM, there were widespread areas of inflammatory cellular infiltration within the myocardium with multinucleated giant cells and granulomas interspersed with lymphocytes. Microscopic field showed up to 10 multinucleated giant cells. In this case, there were focal areas at multiple locations and caused uneven thickness in the left ventricle wall. Idiopathic GCM is very rare and causation of hemopericardium is the unique feature of this case. In this case the direct link of GCM with aortitis and rupture of left ventricle wall resulting in hemopericardium is shown. This case is documented through macroscopic as well as microscopic photographs in H&E, Ziel-Nelson, and GMS staining.     

Sudden cardiac death and myocardial ischemia indicators: a comparative study of four immunohistochemical markers

The postmortem diagnosis of acute myocardial infarction represents a current challenge for forensic pathologists, particularly when death occurs within minutes to a few hours after the ischemic insult. Among the adult population the single most important cause of sudden cardiac death (SCD) is the well-known atherosclerotic coronary artery disease, commonly asymptomatic or unrecognized. The recognition of early myocardial damage using routine hematoxylin and eosin (H&E) staining is possible only if death has occurred at least 6 hours after the onset of the ischemic injury. The usefulness of immunohistochemical markers to the diagnosis of early myocardial damage has been recently suggested because most of them can be visible even serologically as early as few minutes after the beginning of the symptoms. To evaluate the usefulness of plasma and cellular antigens, their distribution patterns have been studied among a group of 18 SCD cases in which a myocardial ischemia was strongly suspected. For the present study, 4 markers have been selected on the basis of their different diagnostic potential as follows: among the plasma markers the C5b-9 and fibronectin, among the cellular markers the myoglobin and cardiac troponin. The results show that only the study of multiple markers such as those selected can provide enough evidence of myocardial ischemia and/or necrosis, supporting the final diagnosis of SCD. No single immunohistochemical staining is ideal for diagnosing early myocardial ischemia but a set of markers can improve the ability of forensic pathologists to detect ischemic areas when no macroscopic or microscopic evidence of necrosis is available. However, the interpretation of data obtained in each individual cannot be isolated from the overall assessment of the factors (cardiopulmonary resuscitation and/or agonal artifacts) that can affect the expression of each marker.     

人体冠心病心肌组织cTnI免疫组织化学研究

目的 研究cTnI免疫组织化学法诊断人体急性心肌梗死的法医病理学意义.方法 应用免疫组织化学法检测人体冠心病心肌组织cTnI的变化,进行图像分析,与HE染色法进行比较.结果 人体冠心病心肌组织急性心肌梗死区域心肌细胞内cTnI免疫组化染色缺染、分布失规律性;梗死修复区域纤维间质cTnI免疫组化染色弱阳性:陈旧性心肌梗死瘢痕区域纤维间质cTnI免疫组化染色阴性.失血性休克组近心内膜心肌细胞内cTnI免疫组化染色轻度增强,并见点灶状心肌细胞内cTnI免疫组化染色缺染.结论 cTnI免疫组织化学检测可以应用于人体急性心肌梗死的诊断.     

Screening of myocardial contraction bands: a comparison between two histological staining methods.

Two histological stains for demonstration of contraction bands (cb): Mallory's phosphotungstic acid hematoxylin (PTAH) and a modification of luxol fast blue (LFB) were compared. Microscopical sections from hearts from 60 autopsies were screened. The regional distribution of the cb lesions was also studied. It was found that PTAH showed cb more consistently than LFB. None of the stains were suitable for screening in the lowest magnification. In cases of cardiac death the cb were often extensive and scattered throughout the myocardium. In non-cardiac deaths with cb these were always discrete and seen only in one location which might be a means of differentiating lesions of pathogenetic importance from agonal ones.     

Heart fatty acid binding protein as a marker for postmortem detection of early myocardial damage

Depletion of heart fatty acid binding protein (H-FABP) from cardiomyocytes with varying post-ischemia intervals was studied in acute myocardial infarction (AMI) model of rat, and 22 human autopsy cases were studied with streptavidin-peroxidase conjugated method (S-P). It was observed that as early as 15 min after ischemia, the depletion of H-FABP could be detected in model rats. With the ischemic time prolonged, the depletion of H-FABP was more and more evident. In all human cases with myocardial infarction, absent H-FABP staining could be found in infarcted area. And in some suspected early myocardial infarction cases, depletion of H-FABP staining could be demonstrated in areas that showed normal hematoxylin-eosin (HE) staining. The blood samples from model rats before ligation, at varying post-ischemia intervals and various postmortem time were measured for plasma concentration of H-FABP with enzyme-linked immuno-sorbent assay (ELISA) method. At 15 min after myocardial ischemia, the concentration of H-FABP was 4 times higher (546.0+/-85.3 microg/l) than that of the baseline level (103.7+/-94.1 microg/l). With the continuation of ischemic time, the concentration of H-FABP increased and peaked at 4 h (1953.5+/-405.3 microg/l), then decreased. The plasma concentration of H-FABP decreased slightly with postmortem time, but was still significant higher at any postmortem intervals than that of baseline level within 48 h after death. The results suggest that H-FABP staining can detect very early ischemic damages in human myocardium and the elevated plasma concentration of H-FABP in rat was an indicator of AMI, which was not affected by autolysis.     

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.     

Is immunohistochemistry a useful tool in the postmortem recognition of myocardial hypoxia in human tissue with no morphological evidence of necrosis?

Myocytes in the border zone of myocardial infarction are under severe hypoxia without characteristic morphology of necrosis, and show ultrastructural features similar to those seen within the first hours after coronary occlusion. This study was carried out to evaluate the possibility that immunohistochemical methods could be used for the early diagnosis of myocardial infarction by detecting areas of hypoxia. Nineteen human sections of formalin-fixed paraffin-embedded myocardial samples showing a necrotic area and its border were submitted to immunohistochemical staining with the markers antimuscle actin, antimyoglobin, antitroponin T, antifibronectin, and anticomplement component C9. Sections were also subjected to azan trichrome and hematoxylin-basic fuchsin-picric (HBFP) staining techniques. Immunohistochemistry and azan trichrome showed that in the border zone there was a pattern of reaction intermediate between the infarcted area and the normal myocardium. The HBFP failed to distinguish these two areas. In conclusion, immunohistochemistry and azan trichrome can recognize myocardial hypoxia. Because hypoxia is an invariable condition in infarction, these techniques can be used to confirm suspected cases of myocardial infarction in which necrosis is not yet evident. However, considering that agonal states may be associated with generalized hypoxia, further studies are needed to confirm the reliability of this procedure in the earlier phases of myocardial infarction.     

早期心肌缺血猝死心肌Ⅰ型胶原的表达

目的探讨Ⅰ型胶原蛋白在心肌早期缺血死后诊断中的法医学价值。方法将收集的案例心肌蜡块分为3组：正常对照组、早期心肌缺血组、心肌梗死组,用免疫组织化学技术（S-P法）,观察猝死心肌内Ⅰ型胶原的表达情况,对其结果进行半定量分析。结果早期心肌缺血组和心肌梗死组心肌细胞质以及细胞核染色阳性,且早期心肌缺血组与心肌梗死组表达强度相近,说明早期心肌缺血组在胶原网结构方面已经发生与心肌梗死相同的改变。结论Ⅰ型胶原可以作为早期心肌缺血的一个诊断指标。     

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。     

Immunohistochemical study of fibronectin for postmortem diagnosis of early myocardial infarction

The postmortem diagnosis of early myocardial infarction has been a puzzling problem in forensic practice. In the present study, an immunohistochemical study of fibronectin (FN) was performed for the first time on 34 autopsy hearts to determine early myocardial infarction with streptavidin/biotin/peroxidase technique. Five cases of definite myocardial infarction showed positive FN staining of cardiomyocytes; of 18 cases where early myocardial infarction was suspected, positive FN staining of cardiomyocytes was found in 15 cases, but no such staining was seen in 11 non-cardiac death controls. The results led to the conclusion that positive FN staining in cardiomyocytes is a reliable marker of acute myocardial infarction and could be used as a new, sensitive method for the postmortem diagnosis of early myocardial infarction. It is worth noting that all cases in this study were autopsied between 8 h and 4 days after death and 5 cases had been fixed in 10% formalin for over 10 years. FN immunohistochemistry still gave satisfactory results in those cases. It seemed that FN was not affected by postmortem autolysis and formalin-fixation and could be used in routine forensic practice, especially for retrospective analysis of cases.     

病毒性心肌炎肌动蛋白的免疫组化观察

对１０例尸检心脏标本进行了肌动蛋白（Ａｃｔｉｎ,Ａｔ）的免疫组化观察。依据Ｄａｌｓ标准的明确或界限性病毒性心肌炎５例,心肌组织内Ａｔ含量减损,呈局灶性或弥漫性淡染,偶见小灶性单个心肌细胞内Ａｔ缺失。心肌梗死２例,心肌组织内Ａｔ大片缺失;非心性死亡对照组３例,心肌组织内Ａｔ呈均匀一致的强阳性染色。结果表明,心肌组织内Ａｔ的免疫组化观察可望提高对不典型病毒性心肌炎诊断的敏感性,同时对区分轻度缺血性与炎症性心肌细胞损伤有参考价值     

Detection of apoptosis in ischemic heart. Usefulness in the diagnosis of early myocardial injury

Myocardial samples of hearts with histologic findings of acute myocardial infarction (group A), sudden coronary deaths without histologic changes (group B), and chronic ischemic heart disease (group C) were analyzed to investigate the appearance of apoptosis in acute and chronic ischemic cardiac disorders. This analysis involved the morphologic detection of DNA strand breaks in myocyte nuclei by the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay and the biochemical determination of DNA laddering in the myocardium using archival formalin-fixed, paraffin-embedded tissue sections of human myocardium. The authors demonstrated that apoptosis of myocardial cells could occur after ischemic myocardial cell injury. In all documented cases of acute myocardial infarction (group A), the infarcted area included extensive presence of both apoptosis and necrosis. In the tissue bordering on and away from the obviously infarcted areas, positive nuclei were intermingled with nonstained normal myocytes. The number of positive nuclei decreased with the distance from the infarction foci. In group B, myocardial samples showed focal or diffuse nuclear positivity of varying degrees for apoptosis, confirming the presence of myocardial ischemic cell death, whereas the histologic diagnosis remained inconclusive. This finding suggests that apoptosis could be used as a marker for acute ischemic injury. In group C, stained nuclei were dispersed with intermingled normal cardiomyocytes.     

大鼠急性心肌缺血后脑钠肽、c-fos基因的表达及法医学意义

目的研究大鼠在急性心肌缺血（acute myocardial ischemia,AMI）后目的基因脑钠肽（brain natriuretic peptide,BNP）和c-fos的mRNA表达变化与AMI发生后所经历时间的关系,为法医病理学鉴定心源性猝死提供依据。方法用结扎法制作大鼠AMI动物模型,结扎成功后观察时间组为10、30、60min和3h,用RT-qPCR、普通PCR检测目的基因BNP和c-fos的mRNA表达变化,同时行HE染色。比较不同时间组间的结果差异。结果RT-qPCR结果显示,BNP在3h组的表达量高于正常组、10min组、30min组及60min组,有显著性差异（P〈0.05）,c-fos除正常组与10min组之间、30min组与3h组之间无显著性差异（P≥0.05）以外,其他各组间均有显著性差异（P〈0.05）,并以60min组c-fos基因的表达量最多。普通PCR未见目的基因不同时间的组间差异。HE染色仅在实验组3h组偶见局部嗜酸性增强、肌纤维呈波浪状等改变。结论c-fos基因可能作为缺血发生30min后的辅助诊断指标。RT-qPCR方法较适合早期AMI的诊断。     

A simple method for postmortem detection of acute myocardial infarction

The analysis of K/Na ion ratio of myocardium was used for the postmortal determination of the early myocardial infarction. The ion content of heart tissue was measured with flame spectrometer after the decomposition of myocardium by Lumatom tissue solubizer. The ion contents and their ratios correlate well with the electrocardiogram, the clinical data, the autopsy and histological findings. In some cases the change of the K/Na ion ratio was the only alteration that suggested an early stage of myocardial infarction. The Lumatom tissue solubizer can be very useful in determination of trace elements from any organic samples.     

多发性软组织挫伤后成人呼吸窘迫综合征──组织学及免疫组织化学研究

本研究应用组织学Ｈ·Ｅ、Ｍａｌｌｏｒｙ、ＰＴＡＨ以及免疫组织化学染色方法对６例多发性软组织挫伤后成人呼吸窘迫综合征者肺组织改变进行了深入探讨。结果表明，所有外伤性呼吸窘迫综合征者肺组织均呈急性充血、出血及水肿改变，且免疫组织化学染色证明，水肿液中含有纤维蛋白（原）成份。在６例中２例可见肺组织局灶性出血坏死，３例有散在性血管内纤维蛋白柱形成及肺泡内透明膜形成。这些改变均属成人呼呼吸窘迫综合征的早期肺损伤。对多发软组织挫伤后呼吸窘迫综合征的形成机理进行阐述。