中介素预处理对大鼠心肌细胞缺氧的保护作用

目的 通过对中介素（intermedin,IMD）预处理的大鼠心肌细胞缺氧后作用机制的研究,为法医病理学研究心脏性猝死机制提供思路. 方法 大鼠H9c2心肌培养细胞随机分为对照组、缺氧组和IMD预处理组.采用MTT比色法、透射电镜、激光共聚焦显微镜和流式细胞术检测各组心肌细胞存活率、细胞超微结构、细胞内游离钙离子浓度（[Ca2＋]i）及细胞凋亡率.结果 与对照组比较,缺氧组细胞存活率明显降低（P＜0.05）,内部超微结构存在损伤,而IMD预处理显著提高细胞存活率（P＜0.05）、减轻缺氧对心肌细胞结构的损伤.缺氧组细胞[Ca2＋]i（荧光强度）和细胞凋亡率较对照组升高（P＜0.05）,IMD预处理降低了缺氧对细胞[Ca2＋]i（荧光强度）和凋亡率的影响（P＜0.05）. 结论 IMD能提高缺氧心肌细胞存活率、减轻缺氧引起的细胞内钙超载从而抑制细胞凋亡,可以揭示心肌细胞缺氧保护作用的机制,为心脏性猝死鉴定提供依据.     

中介素（IMD）对大鼠心肌细胞缺氧-复氧损伤的作用

目的探讨中介素（IMD）对大鼠体外培养心肌细胞缺氧-复氧损伤的作用。方法用大鼠H9c2心肌细胞株制作实验模型,样本分为对照组、缺氧-复氧组（缺氧1h、复氧30min）、IMD组（缺氧-复氧前30min加入10-7mol/L IMD）。采用MTT比色法检测心肌细胞活力;透射电镜观察细胞超微结构;激光共聚焦显微镜观察并测定细胞内钙离子浓度;流式细胞术测定细胞凋亡率。结果与对照组比较,缺氧-复氧组和IMD组细胞存活率显著降低,而IMD处理组明显升高细胞存活率（P〈0.01）;在形态学上,IMD预处理可明显减轻缺氧-复氧对大鼠心肌细胞的损伤;缺氧-复氧组细胞[Ca2＋]i荧光强度和细胞凋亡率比对照组显著升高,IMD预处理可明显降低上述升高的比率（P〈0.01）。结论 IMD对大鼠心肌细胞缺氧-复氧损伤有一定保护作用,提高心肌细胞存活率、减轻心肌细胞钙超载和抑制凋亡是其作用途径。     

博落回对大鼠心肌Ca2＋.Mg2＋-ATPase与SDH活性的影响及超微结构观察

目的探讨博落回对心肌作用的机制。方法SD大鼠36只分为2个实验组和1个对照组,每组12只;2个实验组分别按1/6LD50、1/3LD50剂量的博落回水煎液灌胃,对照组以蒸馏水灌胃。各组大鼠处死后,每组10只取心肌组织制成匀浆,检测Ca2＋.Mg2＋-ATPase与SDH（琥珀酸脱氢酶）的活性;另2只大鼠心肌行超微结构观察。结果1/6LD50组大鼠心肌内Ca2＋.Mg2＋-ATPase与SDH活性较对照组有显著性升高（P〈0.05）;1/3 LD50组大鼠心肌内Ca2＋.Mg2＋-ATPase与SDH活性同对照组比较无显著性差异（P〉0.05）,但呈下降趋势。超微结构观察到实验组大鼠心肌细胞发生凋亡及1/3 LD50组大鼠出现心肌排列紊乱、断裂等征象。结论博落回对大鼠心肌内Ca2＋.Mg2＋-ATPase与SDH的活性有影响作用,并能诱导心肌细胞凋亡。     

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。     

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。     

大鼠急性心肌缺血zif/268蛋白表达及其意义

目的 探讨急性心肌缺血早期不同时间不同区域心肌细胞内原癌基因蛋白zif/268的表达变化,为心肌早期缺血死后诊断提供新指标。方法 建立心肌早期缺血模型,大鼠分为正常、缺血组。采用免疫组化SABC法研究心肌细胞核蛋白zif/268的累积情况。结果 缺血 60min后,缺血区大鼠心肌细胞有部分心肌细胞核呈弱阳性着色,以后随缺血时间延长核阳性增强。正常和缺血30min组及未缺血区心肌细胞核未见有阳性反应。HE染色无明显病理改变。结论 免疫组化染色法检测心肌细胞核zif/268的表达对急性心肌缺血的死后诊断是一种有价值有意义的手段。     

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 心肌细胞结蛋白在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     

青壮年猝死综合征心肌细胞内Cx43的表达

目的观察连接蛋白43（Cx43）在青壮年猝死综合征（SMDS）者心肌细胞的表达,并探讨其法医学意义。方法筛选法医尸检案例45例,其中SMDS组、冠心病猝死组及对照组各15例。采用免疫组织化学和图像分析技术对不同组别Cx43蛋白在心肌细胞内的表达进行阳性单位（PU）定量检测,分析Cx43蛋白在各组表达的差异。所得数据进行统计学分析。结果 SMDS组心肌Cx43染色明显减弱,阳性着色条带分布不均、深浅不一,有的呈散在颗粒状;冠心病猝死组亦见类似变化;对照组未见明显变化。经统计分析发现,3组心肌细胞内Cx43表达的PU值存在显著性差异（P〈0.05）。结论 SMDS死前存在心肌缺血及心电紊乱,应属心性猝死范畴。     

慢性脱氧麻黄素染毒大鼠心肌中热休克蛋白的免疫组织化学研究

本文对慢性脱氧麻黄素（MethamphetamineMeth；1mg／kg／day2—8周）染毒大鼠心肌中热休克蛋白的代表物HeatshockProtein70（HSP70）和Ubiquitin进行了免疫组织化学的研究。实验结果显示早期Meth染毒阶段（2周组），虽然心肌组织未出现明显的病理形态学变化，但在心肌细胞、心内膜上皮细胞、血管平滑肌细胞和毛细血管内皮细胞内均可检出HSP70和Ubiqui－tin。以后随着染毒时间的延长，HSP70和Ubiquitin在细胞内的表达也增强。而对照组大鼠心肌组织在实验期间缺乏明显的表达。这些发现提示在受到Meth作用时，HSP70和Ubiquitin在心肌细胞内的表达优先于病理形态学改变的出现。且石蜡组织切片中热休克蛋白的免疫组织化学研究是早期诊断心肌细胞损伤的一个良好方法。     

大鼠死后心血吗啡浓度变化的HPLC检测

采用高效液相邑谱分析技术（HPLC）检测治疗量及中毒量吗啡肌注大鼠死后心血中吗啡浓度变化。结果表明，以治疗量吗啡肌往大鼠，在死后96h内，心血中吗啡浓度随死后时间增加而显著升高（P＜0．01），吗啡浓度水平与死后时间里显著正相关；以中毒量吗啡肌注大鼠，在死后12h内，心血吗啡浓度无明显变化；死后24h、48h及96h，随死后时间延长，心血中吗啡浓度逐渐升高（P＞0．01），其递增强度不如治疗量吗啡组大鼠的明显.本研究证实，死后尸体心血吗啡浓度明显受生前剂量的影响，且在死后96h内，随死后时间增加．心血中吗啡浓度少数不断增高。     

挤压伤大鼠早期心脏损伤的细胞机制

目的观察挤压伤大鼠血清对培养的新生大鼠心肌细胞的某些作用,拟阐明挤压伤早期心肌细胞损伤的细胞机制。方法培养1～3d龄SD大鼠心肌细胞,观察挤压伤大鼠血清对心肌细胞搏动频率、表面积、蛋白质含量、3H-亮氨酸掺入、胞内钙浓度和Fos蛋白表达的影响。结果与正常大鼠血清组比较,挤压伤大鼠血清培养的心肌细胞搏动频率(次/min)由88.3±20.6降为26.4±16.7,心肌细胞表面积、蛋白质含量、3H-Leu掺入、胞内游离钙浓度(nmol/L)和Fos蛋白表达阳性指数增加。结论挤压伤大鼠血清通过抑制细胞搏动,增加胞内钙浓度诱导Fos蛋白的表达,引起心肌细胞肥大,介导挤压伤早期的心脏损伤。     

挤压伤大鼠血清对血管内皮细胞凋亡的作用及机制探讨

目的观察挤压伤大鼠血清对血管内皮细胞凋亡的影响及可能机制。方法培养小牛主动脉内皮细胞,观察挤压伤大鼠血清对培养的血管内皮细胞凋亡及胞内钙浓度的影响,并检测血浆内皮素-1(endothelin-1,ET-1)及心钠素(atrial natriuretic peptide,ANP)的含量。结果与正常大鼠血清相比,挤压伤大鼠血清致细胞的凋亡百分数由(8.26±1.75)%降为(2.75±0.90)%,胞内钙浓度由(96.98±3.95)nmol/L增加到(118.79±3.22)nmol/L,挤压伤大鼠血浆内皮素-1和心钠素含量显著增高。结论肢体挤压伤大鼠血清可抑制血管内皮细胞的凋亡,此效应可能与内皮素-1和心钠素诱发胞内钙浓度增加有关。     

Postmortem blood free and total morphine concentrations in medical examiner cases

This purpose of this study was to determine the relationships between postmortem free morphine and total morphine levels in a large series of medical examiner morphine and heroin related deaths. Free morphine, total morphine, and 6-monoacetylmorphine (6-MAM) concentrations were measured by gas chromatography-mass spectrometry (GC-MS) in 87 medical examiner cases over 20 months. The mean total morphine concentration, mean free morphine concentration, and mean percent free morphine for all cases were: 2.3 mg/L (SD 5.2 mg/L), 0.5 mg/L (SD 1.6 mg/L), and 19.4% (SD 22.8%); respectively. Regression analyses showed weak correlations between total and free morphine concentrations over the entire concentration range (0 to 36.6 m/L, r = 0.603, n = 91) and over a subset concentration range of 0 to 1.0 mg/L (r = 0.369, n = 54). Twenty-three out of 56 (41%) tested positive for 6-MAM, indicative heroin abuse cases. Lower total and free morphine concentrations and a higher percent free morphine were found in individuals with detectable 6-MAM. Comparing blood concentrations for cases with and without detectable 6-MAM demonstrated mean total morphine concentrations of 0.9 mg/L versus 2.1 mg/L (p = 0.05), mean free morphine concentrations of 0.3 mg/L versus 0.4 mg/L (p = 0.21), and mean percent free morphine of 34.7% versus 13.7% (p < 0.003), respectively. Our findings demonstrate higher free to total morphine ratios in individuals with detectable 6-MAM than in individuals without 6-MAM. The database established in this study may assist medical examiners in the evaluation of postmortem blood opiates regarding the cause of death in opiate related ingestion cases.     

The role of ethanol abuse in the etiology of heroin-related death

Toxicology analyses and other forensic science data were used to examine the mechanisms through which ethanol increased the risk for death caused by injected street preparations of heroin. The authors studied 505 victims of fatal heroin overdose and compared subjects who had concentrations of blood ethanol greater than 1000 mg/L (n = 306) with those who had concentrations less than, or equal to 1000 mg/L (n = 199). We found significant negative correlations between concentrations of ethanol and morphine (a heroin metabolite) in blood (R2 = 0.11, P = 0.0001 for log10-transformed variables) as well as between concentrations of blood ethanol and bile morphine (R2 = 0.16, P = 0.0001 for log10 bile morphine versus blood morphine). Toxicologic evidence of infrequent heroin use was more common in decedents with blood ethanol concentrations greater than 1000 mg/L than in those with lower concentrations. Our data suggest that ethanol enhances the acute toxicity of heroin, and that ethanol use indirectly influences fatal overdose through its association with infrequent (nonaddictive) heroin use and thus with reduced tolerance to the acute toxic effects of heroin.     

Morphine Concentrations in Stomach Contents of Intravenous Opioid Overdose Deaths

Abstract:  Death caused by heroin overdose is almost always the result of intravenous injection of the drug in Australia. We briefly describe a case where a heroin overdose was initially thought to be the result of oral ingestion of the drug, primarily as a result of higher concentrations of morphine in stomach contents than in blood. During the subsequent criminal trial and investigation, however, the issue of the entero-hepatic circulation of morphine was raised as a possible reason for the presence of morphine in the stomach contents. In this study, we report on the distribution of opioids in blood, stomach contents, urine, liver, and bile in 29 deaths caused by intravenous heroin overdose. The mean total and free blood morphine concentrations were 0.60 and 0.32 mg/L , respectively, and the mean stomach contents total morphine concentration was 1.16 mg/kg. All cases had detectable morphine in the stomach contents, and 24 of 29 cases (83%) had higher concentrations of total morphine in stomach contents than in blood. The mean total morphine concentration in bile was c. 100 times that in blood, and the liver total morphine concentration averaged twice that of blood levels. We conclude that the entero-hepatic circulation of morphine and subsequent reflux of duodenal contents back into the stomach can result in the deposition of morphine in gastric contents. Consequently, the relative levels of opioids in blood and stomach contents cannot be used to determine the site of administration of the drug.     

A rapid GC-MS method for the determination of dihydrocodeine,codeine, norcodeine,morphine, normorphine and 6-MAM in urine

The presence of the heroin metabolite 6-monoacetylmorphine (6-MAM) in urine is used to definitively identify recent heroin abuse. A rapid and sensitive GC-MS method for the simultaneous analysis of codeine, norcodeine, morphine, normorphine and 6-MAM in urine was developed and successfully applied to the analysis of 321 'heroin-positive' urine specimens from individual subjects (identified by the presence of 6-MAM), to provide quantitative urinary opiate excretion data for heroin abusers.The cohort analysed was composed of 238 males (age range 16-53 years) and 83 females (age range 16-50 years). The concentrations of free 6-MAM, morphine and codeine determined in these 321 specimens ranged between 103-246,312, 129-193,600 and 103-519,000 microg/l, respectively. Free norcodeine and normorphine concentrations were found to range between 143-50,200 and 205-149,700 microg/l, respectively. A statistically significant relationship was determined between the subject age and the 6-MAM concentration, possibly indicating opiate tolerance in these individuals.     

Role of alcohol in heroin overdose

The relationship between ethanol and risk of heroin overdosage was studied. Statistical processing of the results of forensic chemical analysis (460 expert evaluations) carried out in Chelyabinsk Regional Bureau of Forensic Medical Expert Evaluations in 2000 was carried out. The results of morphine and ethanol measurements in the blood and urine from corpses where deaths ensued from narcotic or ethanol poisoning, were analyzed. The concentrations of morphine in the blood and urine were measured on a gaseous chromatographer with mass-selective detector (Hewlett Packard HP 6890/HP-5972). Methods for measuring urinary and blood morphine are described. The results of statistical analysis demonstrated relationships between the age and ethanol concentrations in the blood and urine; blood ethanol and total urinary and blood morphine concentrations; blood concentration of free morphine and presence of 6-monoacetylmorphine in the blood. The authors conclude that the presence of ethanol in the blood together with morphine drastically augments the risk of rapid death from respiration arrest. It can also lead to a relatively high risk of overdosage in experienced narcomaniacs using heroin and ethanol.     

吸毒者头发中海洛因、6-单乙酰吗啡、吗啡、可待因和乙酰可待因的分析及评价

目的确定海洛因吸毒者头发中海洛因、6-单乙酰吗啡（6-MAM）、吗啡（MOR）、可待因（COD）和乙酰可待因（AC）的浓度并考察其与国际毛发分析协会（Society of Hair Testing,SOHT）建议标准的适用性。方法 50个头发样品经冷冻研磨处理后采用液相色谱-串联质谱方法分析。结果所有样品中均检出6-MAM,并且浓度高于SOHT所建议的0.2 ng/mg,其中海洛因、6-MAM、MOR、COD和AC的浓度与其它研究报道无明显差异。头发中6-MAM：MOR的比率在0.15~36.27范围。结论由于各实验室间毛发样品前处理方法不同,而且存在吸食毒品中成分、剂量、吸食方式、代谢、头发颜色等诸多个体差异,本研究认为采用头发中6-MAM：MOR的比率大于1.3标准难以应用于鉴定海洛因吸毒。