窦房结中央动脉狭窄与心源性猝死

近年来国内外学者相继报道由单纯窦房结中央动脉狭窄引起的猝死。本文就窦房结中央动脉的解剖、组织学特点、病变特点进行综述,探讨窦房结动脉狭窄引起猝死的机制,以期为相关法医病理学死因鉴定提供理论基础。     

The role of environmental factors in the causation of sudden death in infants: two cases of sudden unexpected death in two unrelated infants who were cared for by the same babysitter

We report two cases of sudden unexpected death in two unrelated African American female infants, 2 months and 4 months old. Both infants were attended to by the same babysitter in the same apartment and died 39 days apart in the same bed and in the same bedroom. The autopsy of the first infant revealed sudden unexplained death in an infant. Toxicologic analysis for carbon monoxide (CO) was not performed because it was not suspected. When the second infant died, investigation into the ambient air quality within the apartment revealed high levels of CO emanating from a poorly ventilated and defective hot water heater, which was located across a hallway from the bedroom where the two babies died. CO saturation levels in the postmortem blood samples of the two babies were elevated and were similar (13% and 14%). Nicotine and cotinine were not detected in the blood sample of the two infants. Cherry-red livor mortis was absent. Acute CO intoxication was determined to be the underlying cause of these two unexpected deaths. These two cases underscore the need to integrate ambient air analysis and postmortem CO analysis as routine components of the comprehensive death investigation of infants who die suddenly and unexpectedly.     

Sarcoidosis and mechanisms of unexpected death

Sarcoidosis is a multisystem disease of uncertain etiology characterized by multifocal areas of discrete and confluent granulomatous inflammation that may rarely be responsible for sudden and unexpected death. Two cases are reported to demonstrate disparate pathological features in fatal cases, one involving cardiac sarcoidosis, and the other neurosarcoidosis with hypothalamic infiltration. Sarcoidosis in individuals dying suddenly may be completely unrelated to the death, contributory or causal. Cardiovascular causes of sudden death in sarcoidosis include arrhythmias associated with cardiomyopathy and ischemia, ventricular rupture, and cor pulmonale due to pulmonary hypertension; respiratory causes include hemorrhage and upper airway obstruction; central nervous system causes include arrhythmias from infiltration of autonomic centers, epilepsy, and obstructive hydrocephalus from brainstem involvement; and gastrointestinal deaths may be due to hemorrhage from esophageal varices associated with portal hypertension. The diagnosis relies on the demonstration of typical noncaseating granulomas and the exclusion of other infective and environmental diseases with similar histopathological findings.     

Infant death scene investigation and the assessment of potential risk factors for asphyxia: a review of 209 sudden unexpected infant deaths

At the Wayne County Medical Examiner Office (WCMEO) in Detroit, Michigan, from 2001 to 2004, thorough scene investigations were performed on 209 sudden and unexpected infant deaths, ages 3 days to 12 months. The 209 cases were reviewed to assess the position of the infant at the time of discovery and identify potential risk factors for asphyxia including bed sharing, witnessed overlay, wedging, strangulation, prone position, obstruction of the nose and mouth, coverage of the head by bedding and sleeping on a couch. Overall, one or more potential risk factors were identified in 178 of 209 cases (85.2%). The increasing awareness of infant positions at death has led to a dramatic reduction in the diagnosis of sudden infant death syndrome at the WCMEO. This study suggests that asphyxia plays a greater role in many sudden infant deaths than has been historically attributed to it.     

The influence of site of collection on postmortem morphine concentrations in heroin overdose victims

When assaying for postmortem morphine concentration, significant site sampling variability exists between central and peripheral sampling sites and even within sampling regions of the body. To study the variation, 76 suspected heroin overdoses were identified. Each had femoral artery (FA) and vein (FV), left and right ventricle and pooled heart blood samples obtained at autopsy. Forty-four tested positive for morphine. Morphine concentrations were determined by gas chromatography/mass spectrometry, with sampling site differences reported as log-transformed ratios and compared by signed rank test.The mean FA to FV ratio for total morphine was 1.2 (range 0-4.5). The ratio for left heart to right heart total morphine was 1.1 (range 0.4-3.2). Left ventricular to FV total morphine ratio was 2.0 (range 0.6-6.9). In these opioid overdose deaths, FA and FV morphine concentrations are usually similar, although up to 4.5-fold differences were noted. Centrally obtained morphine concentrations are on average twice as high compared with peripheral morphine concentrations. Left and right ventricular morphine concentrations were usually similar, although up to 3.2-fold differences were noted (left side higher).     

连接蛋白43与心性猝死的相关性研究进展

部分心性猝死者死后尸检时心脏没有发现明显病理学异常征象,过去均将其归属原因不明的猝死范畴。近年来研究显示,心肌连接蛋白43（connexin43,Cx43）表达对于心性猝死的诊断具有十分重要的意义。本文就Cx43结构、功能以及在心血管疾病发生发展中的作用与法医学意义作一综述。     

A case of sudden infant death due to a primary cardiac sarcoma

The case reported herein concerns the unexpected death of a 3-month-old female newborn who suddenly collapsed in her mother's arms and was dead on arrival at the hospital. The clinical histories of the baby and her parents were negative for symptoms or signs of illness, even those of cardiovascular origin. Furthermore, no clinical appearance of a pathologic status was noted by pediatricians after the birth until the last emergency recovery. The autopsy excluded external and internal signs of violence but revealed a large primary cardiac tumor arising from the free wall of the left ventricle, which had totally invaded the heart causing mitral valve deformation. Histological examination showed a low-grade sarcoma that completely infiltrated the myocardial tissue. The pathogenesis of this sudden infant death was postulated as being owing to a fatal ventricular fibrillation combined with a tumor-related restrictive cardiomyopathy obstructing left ventricular filling.     

青壮年猝死综合征研究现状

青壮年猝死综合征(SMDS)一直是国内外医学界尤其是法医学领域研究的热点,近来对SMDS的发病特点及致病机制等都有广泛而深入的研究,但仍有部分关键问题尚未解决。本文通过文献复习并结合法医检案,分别从分子遗传学、免疫组织化学、冠状动脉结构或功能异常、自主神经调节作用等方面介绍SMDS的研究进展。     

Further observations on the speed of death in hanging

Given that most fatal hangings are suicidal and occur in locations that have been selected to conceal this activity (thus maximizing the chances of a lethal outcome), there has been very little corroboration of the speed with which unconsciousness and death may occur. A 35-year-old male is reported who committed suicide by hanging immediately after talking to his spouse. Police investigations confirmed her reliability as a witness indicating that lethal anoxia in this case had occurred within a very short time (most likely in less than 1 min) of suspension. The speed with which death may result from hanging not only gives an insight into fatal pathophysiological mechanisms, but also provides useful information for situations where a lethal outcome is to be avoided, or is not intended. For example, individuals at risk of suicide who are being monitored in institutional facilities need to be constantly under direct visual surveillance as significant hypoxia can be rapidly induced, parents and caregivers with infants and children in potentially unsafe sleeping environments need to realize how swiftly death or irreversible anoxic brain damage may occur from neck compression, and those who engage in recreational asphyxia should be informed just how quickly a fatal outcome may ensue.     

An unusual case of sudden unexpected death: postmortem investigation and biomechanical analysis of the cervical spine

A naked man died under peculiar circumstances and the postmortem examination revealed unexpected lesions in the cervical spine. Investigations of the cervical spine (computed tomography, magnetic resonance imaging, and histological examination) showed that a piece of bone was torn of the anterior part of vertebra C6 and that there was fresh bleeding in the surrounding tissue. The cause of death remained unclear but was most likely cardiac arrhythmia initiated by beta-2 agonist inhalation due to an acute asthmatic attack. Data from biomechanical investigation using finite element analysis supported the conclusion that the cervical spine injury was secondary to impact during falling as a consequence of the cardiac arrhythmia.     

东莞地区外来工青壮年猝死综合征的流行病学研究

目的研究东莞地区青壮年猝死综合征(SMDS)的流行病学特征。方法对东莞市公安局1990～2001年的法医学检案中遴选的284例SMDS案例资料进行回顾性研究。结果分析SMDS猝死者的籍贯、年龄、性别、死亡季节的分布及死亡经过、尸检所见的特征。结论此项研究为下一步进行SMDS的流行病学研究积累了初步资料。     

心脏性猝死心肌组织N-Cadherin、Bax表达变化及评价

目的观察心脏性猝死者(SCD)心肌组织的神经性钙粘附蛋白(N-Cadherin)和Bax的表达变化,探讨其法医学意义。方法分别选取心脏性猝死和排除心脏疾病死因的尸检案例心肌组织标本各33例、29为SCD组和对照组。光镜下观察心肌组织病理学改变,检测N-Cadherin和Bax在心肌组织中的表达变化,并进行统计学分析。结果 N-Cadherin在SCD组心肌中表达呈弱阳性,排列紊乱,显著低于正常心肌,正常心肌组织中N-Cadherin呈强阳性表达,细胞间界限明显,排列整齐。Bax在SCD组表达呈阳性,显著高于正常心肌。结论 N-Cadherin和Bax的变化表达对心脏性猝死鉴定有意义。     

Concurrent detection of heroin, fentanyl, and xylazine in seven drug-related deaths reported from the Philadelphia Medical Examiner's Office

Recreational drugs, such as cocaine and heroin, are often adulterated with other pharmacological agents to either enhance or diminish the drug effects. Between April 21, 2006 and August 8, 2006, the Philadelphia Medical Examiner's Office detected xylazine (a veterinary sedative) and fentanyl (a synthetic opioid) in specimens taken from seven cases. Initial immunoassay screening was performed on urine and blood for fentanyl, opiate, cocaine, phencyclidine (PCP), and benzodiazepines. All tests reported positive were confirmed by gas chromatography-mass spectrometry. All seven xylazine positive cases tested positive for fentanyl and six cases tested positive for 6-acetylmorphine (a metabolite and definitive marker for heroin). The seventh case was positive for morphine and had a history of heroin abuse. Xylazine was present in urine in all seven cases and blood levels were detected in three cases. The blood concentrations ranged from trace to 130 ng/mL. Fentanyl was present in the blood and urine in each case and blood concentrations ranged from 4.7 to 47 ng/mL. Adulteration of illicit drugs has become an epidemic health concern for drug users. Healthcare professionals need to be aware of this issue, so the patients can be treated in an effective, timely manner.     

Littre hernia--a rare cause of unexpected death in the elderly

A rare case of sudden and unexpected death is reported in an 87-year-old woman who was found dead at her home. At autopsy, the most striking finding was of a right-sided direct inguinal hernia containing a 20 mm infarcted Meckel diverticulum, with proximal small intestinal obstruction. Significant stenosing atherosclerosis was present in all three major epicardial coronary arteries, but with no histological evidence of acute or chronic ischemic myocardial damage. Death was attributed to small intestinal obstruction due to direct inguinal herniation (and infarction) of a Meckel diverticulum (a Littre hernia), complicating ischemic heart disease. Although Littre hernias are not a reported cause of sudden death in the elderly, congenital gastrointestinal anomalies may rarely play a significant role in terminal episodes well beyond childhood years. The autopsy assessment of sudden death at any age involves detailed examination of the entire length of the intestinal tract.     

基质金属蛋白酶2在冠心病猝死心肌中的表达

目的探讨基质金属蛋白酶2（mmp2）在冠心病猝死（SCD）心肌细胞和间质中的表达与SCD的关系。方法选取本教研室2003年51例死亡鉴定病例,分为SCD组,患有冠心病但非SCD组（对照组1）,无严重冠脉粥样硬化（As）病变和其它心血管疾病组（对照组2）,无严重As病变但有其它心脏病组（对照组3）。采用免疫组化SABC法染色及图像分析技术,检测mmp2在各组心肌细胞和间质内表达的阳性率（R值）和平均灰度值（H值）,并比较各组间的差异。结果SCD组与3个对照组之间心肌细胞内romp2H值的差异均有显著性意义;SCD组与对照组2和3之间心肌间质内mmp2H值的差异有显著性意义;镜下各组心肌间质及心肌细胞内表达的阳性率差别明显。结论心肌间质及心肌细胞内mmp2同相表达增高与SCD的发生有密切关系,联合检测心肌和间质mmp2的表达对诊断SCD有重要意义。     

Sudden death in toddlers caused by influenza B infection: a report of two cases and a review of the literature

Sudden fatal cases of influenza B infection in a 4-year-old girl and a 2-year-old boy are presented. Both children complained of abdominal pain without respiratory, neurologic or cardiac symptoms; additionally the girl had vomiting within 2 days of death. Autopsy revealed histological changes in the respiratory system consistent with a viral infection. Influenza B infection was identified by immunohistochemistry in the girl and real-time polymerase chain reaction in the boy. Additional testing including cultures, toxicology, and screening for metabolic disorders were negative. These cases illustrate the usefulness of viral testing, especially for influenza, in the medical legal autopsy of children even when the classic respiratory symptoms of flu are lacking.     

冠心病猝死冠脉斑块组成成分的病理形态学改变

目的探讨冠心病猝死(SCD)组和对照组冠脉粥样硬化斑块纤维帽厚度和脂质核心百分比的差异。方法随机挑选病例及心脏标本共64例,分为SCD组和对照组。在冠脉粥样硬化最严重的部位取材,制片,并行HE染色,显微镜观察冠脉的病理变化和斑块的组成,采用图像分析系统对冠脉斑块纤维帽厚度和脂质核心与整个斑块的百分比进行定量分析,所得数据用SPSS11.5统计软件进行数据分析。结果SCD组中,冠脉粥样硬化病变Ⅳ级21例,Ⅲ级15例,对照组中冠脉粥样硬化病变Ⅳ级12例,Ⅲ级16例,两组在病变的严重程度上未见显著性差异(P>0.05);两组冠脉粥样硬化斑块纤维帽的厚度和脂质核心百分比均有显著性差异(P<0.01)。结论SCD组与对照组在冠脉粥样斑块的纤维帽厚度和脂质核心百分比大小等两方面均存在显著性差异;对SCD的病理诊断和法医学鉴定都具有重要意义。     

青壮年猝死综合征SCN2B、SCN4B基因检测

目的寻找SCN2B、SCN4B基因的变异位点,探讨其与青壮年不明原因夜间睡眠中猝死(SMDS)的关系。方法提取SMDS病例组及健康对照组的基因组DNA,采用聚合酶链式反应(PCR)方法扩增SCN2B、SCN4B基因编码区外显子、外显子-内含子交界区以及3'侧翼区序列,直接行DNA测序以明确遗传变异类型。结果在病例组中共检测到4个变异位点,c.237+27AG,c.*38CT,c.174CT(p.C58C)和c.*7CT。结论本研究首次对中国人SMDS病例进行了SCN2B、SCN4B基因的检测,上述基因是否为中国人SMDS的易感基因尚有待进一步研究证实。