[Early expression of hypoxia-inducible factor-1 alpha after acute myocardial ischemia in rats].

OBJECTIVE: To observe the changes of hypoxia-inducible factor-1 alpha (HIF-1alpha), the expression in the early stage (within 6 h) of acute myocardial ischemia and to explore the potential forensic application. METHODS: SD rats were randomly divided into one control group, one sham operation group and five myocardial ischemia groups which received ligation of the left anterior descending (LAD) coronary artery. The five experiment groups divided into 15min, 30min, 1 h, 3 h and 6h after LAD ligation. The expression of HIF-1alpha was detected by immunohistochemistry, immunofluorescence and Western blotting, respectively. RESULTS: Both the control group and sham operation group showed no expression of HIF-1alpha, whereas the expression of HIF-1alpha could be weakly detected beneath the endocardium at 15 min after LAD ligation. With the increase of myocardial ischemia process, the positive staining gradually extended from endocardium to epicardium, reached the peak at 3 h, and began to decrease gradually at 6h after LAD ligation but still maintained at a relatively high level. In addition, the expression of HIF-1alpha without a time-dependent way was also detected in full thickness of the right ventricle in occurrence of ventricular arrhythmia after LAD ligation. CONCLUSION: HIF-1alpha may be regarded as a sensitive marker for sudden cardiac death induced by early acute myocardial ischemia, and may also be helpful for the diagnosis of fatal arrhythmia.

[Time-dependent expression of vascular endothelial growth factor after acute myocardial ischemia in rats].

OBJECTIVE: To investigate the immunohistochemical distributions and expressions of vascular endothelial growth factor (VEGF) in the model of rat myocardial ischemia. METHODS: The model of myocardial ischemia was established by ligating the left anterior descending (LAD) coronary artery of rats. The changes of VEGF expression were detected by immunohistochemistry and Western blot at time points after myocardial ischemia. The electrocardiographic changes were evaluated uninterruptedly. RESULTS: The expression of VEGF was not be found in control group. Fifteen minutes after LAD ligation, weak positive expression of VEGF were found in the ischemic myocardium. The expression of VEGF reached the peak at 3 hours after ligation. The VEGF distribution was mainly localized in the ischemic and peri-ischemic regions. Six hours after LAD ligation, the expression of VEGF decreased comparing with 3 hours and showed a relatively higher level. Fatal arrhythmia was found in nine rats by the electrocardiograph. CONCLUSION: The immunohistochemical staining of VEGF could be helpful for investigating the location and severity of acute myocardial ischemia. Fatal arrhythmia may be secondary to myocardial ischemia.

[Mechanism of methamphetamine intoxication and its medical identification].

Methamphetamine (MA) is a representative drug of amphetamine-type stimulants for central nervous system and has become one of the most dangerous drugs in the world recently. The present article reviews the pharmacological effects, distribution, metabolism, intoxication mechanism, the effects of MA on cardiovascular and central nervous systems of MA, and the current situation of forensic investigation on MA.

[Twenty autopsy cases of anaphylactic shock induced by cephalosporins].

OBJECTIVE: To explore the characteristics of autopsy cases of anaphylactic shock induced by cephalosporins and provide the evidences in forensic medicine. METHODS: Twenty cases of anaphylactic shock induced by cephalosporins were collected from April 2005 to August 2009 in judicial expertise center of China Medical University, and the characteristics of the cases were analyzed retrospectively. RESULTS: The age of decedents ranged from 40 to 60 years. Ninety percent of cases were from local medical centers and private clinics. The symptoms of the shock appeared 30 s-150 min after the administration of the drug, and death occurred 10 min-210 min after the appearance of the shock symptoms. In all cases, various degrees of eosinophil infiltration were observed in trachea and the lungs. Serum IgE detected by ELISA method was normal value in 14 cases. CONCLUSION: In fatal anaphylactic cases, little specific findings are detected during postmortem and microscope examination. For this reason, the determination of cause of death in these cases requires comprehensive analysis combined with clinic information and excludes other diseases leading to the sudden death.

[Application of brain natriuretic peptide in evaluation of cardiac function in forensic medicine].

Brain natriuretic peptide (BNP) is a major marker for evaluating cardiac function and has been widely used in clinical practice. Recent researches show that BNP is also useful for identification of sudden cardiac death in forensic pathology. This article reviews the molecular structure and biological characteristics of the BNP and its application as a functional indicate in forensic medicine. It shows that the expression of BNP in cardiac muscles, together with the expression of BNP in blood and pericardium liquid can be used to evaluate the pathological physiology changes and dysfunction degrees of the heart during the cardiac sudden death.

[The analysis of pericardial fluid in forensic practice].

Pericardial fluid is a kind of serous fluid in pericardial cavity. Because blood undergoes postmortem changes such as autolysis and putrefaction, vitreous humor is limited,cerebrospinal fluid is easily mixed with blood, pericardial fluid, on the other hand, exists in a closed cavity and can be hardly contaminated by postmortem changes, and also is easily obtained. Pericardial fluid not only plays an important role in clinic practice, but also is widely applicable in forensic practice. This paper briefly presented the properties of pericardial fluid and its clinical significance. It reviewed biochemical changes in decedents died of heart diseases, drowning and asphyxia, and explored the significance in medico-legal investigation. Moreover, application of pericardial fluid in forensic serology, forensic toxicological analysis and other fields were also discussed. Pericardial fluid analysis may provide important information for determination of the cause of death with further investigation concerning forensic applicability of pericardial fluid.

[The application of biochemical indexes detecting in sudden cardiac death in forensic autopsy].

Sudden cardiac death(SCD) from early myocardial ischemia is often lack of typically morphological findings and clinical manifestation, thus cases of SCD may be suspected as criminal cases. It is necessary to clarify the cause of death, which is significance for medico-legal investigation. This article reviewed the latest advancement in the studies on the application of inorganic ions, CK-MB, cTn, ANP and BNP for certification of death from SCD in order to provide a practical way for diagnosis of SCD in forensic pathology.