芍药甘草汤的镇痛作用机制

目的：探讨芍药甘草汤的镇痛作用机制。方法：采用甲醛致痛实验观察其Ⅰ相和Ⅱ相疼痛反应,并测定冰醋酸致痛小鼠血清和脊髓中一氧化氮（NO）浓度变化。结果：芍药甘草汤对甲醛致痛模型动物Ⅰ相和Ⅱ相疼痛反应均呈现剂量依赖性抑制作用;明显降低冰醋酸致痛模型小鼠血清及脊髓中NO浓度,结论：芍药甘草汤的镇痛部位既在外周神经末梢,亦可能在中枢神经,其镇痛作用机制可能与一种新的第二信使神经递质NO有关。     

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.     

一氧化碳中毒血分光光度定量分析法比较

目的比较7种一氧化碳中毒血样分光光度含量测定方法的特点及适用性。方法用空白血添加一氧化碳配制不同浓度的样品,采用双波长法、还原法（3种）、切线法和导数光谱法（2种）进行检测,对各种方法线性范围、重现性和操作中注意事项等内容进行考察,并用实际案件检材验证和比较。结果还原法一在30%~70%、还原法三在20%~100%,其他方法在20%~70%范围内,线性关系良好;样本浓度超过或低于50%,采用切线法有一定误差;导数法及还原法三因需要制备CO饱和样本,操作略微繁琐,但导数光谱法计算结果准确性好。结论几种方法均可用于一氧化碳中毒血的检测,实验结果可为方法的实际应用提供借鉴和帮助。     

Diesel fumes do kill: a case of fatal carbon monoxide poisoning directly attributed to diesel fuel exhaust with a 10-year retrospective case and literature review*

While it is known that diesel fuel combustion engines produce much lower concentrations of carbon monoxide (CO) than gasoline engines, these emissions could certainly generate lethal ambient concentrations given a sufficient amount of time in an enclosed space and under suitable environmental conditions. The authors report a case of CO poisoning which was initially referred for autopsy as a presumed natural death of a truck driver found in the secure cab of a running diesel tractor trailer truck. Completion of the preliminary investigation ascribed death to complications of ischemic heart disease (IHD), pending toxicological analysis that included quantification of CO. When the toxicology results showed lethal blood COHbg, the cause of death was re-certified as CO intoxication secondary to inhalation of (diesel) vehicular exhaust fumes. Because of the unique source of fatal CO intoxication in this case, the contributory IHD and the possible contaminants in the putrefied blood, a 10-year retrospective review was conducted on all nonfire related CO deaths autopsied (n = 94) at the Office of the Chief Medical Examiner in Louisville, KY from 1994 to 2003. For validation of the COHbg detection method used by the Kentucky Office of Forensic Toxicology (KYOFT), blood samples from these cases along with controls were submitted to three laboratories using various analytical methods yielding no statistically significant differences. Lastly, an extensive literature review produced no scientifically reported cases of fatal CO poisoning attributed to diesel fuel exhaust.     

Comparison of Different Analytical Methods for the Determination of Carbon Monoxide in Postmortem Blood

The determination of carbon monoxide (CO) and carboxyhemoglobin (COHb) is of utmost importance in forensic toxicology to determine the cause of death in cases of CO poisoning, fire, and explosions. To this end, reliable and updated analytical methods are required. In this paper, four different methods for the determination of carbon monoxide in postmortem blood samples were compared: (i) the spectrophotometric determination of COHb applying the method proposed by Rodkey and modified by Beutler–West, (ii) the spectrophotometric determination of CO using a micro-diffusion-based method, (iii) the determination of CO by gas chromatography coupled to a TCD detector, and (iv) the determination of COHb by blood gas analysis. Three postmortem blood samples were analyzed with all methods, and the results were comparable. The applied methodologies showed different features depending on the sensitivity, sample preparation, and volume. The HS-GC/TCD method in our hand was the most appropriate, on postmortem samples, and versatile to apply. Unfortunately, only a limited number of postmortem blood samples were available for this study due to the rarity of that kind of intoxication in our jurisdiction.     

The causes of death in fire victims

In 169 consecutive cases of autopsied fire victims about 50% had lethal levels of carboxyhemoglobin. Soot in the respiratory tract was found in about 90% of the cases. The age distribution of the fire victims showed significantly less persons in the 15-35-year group than should be expected according to the age distribution of the population, presumably due to greater agility of younger people. More than half of the fire victims had alcohol in the blood exceeding 0.05%, and alcohol intoxication should be considered accessary to many deaths in fire. The characteristic biphasic distribution of carboxyhemoglobin in fire victims together with other observations suggest that the principal causes of death are carbon monoxide followed by carbon dioxide poisoning and/or oxygen deficiency, while the influence of heat is considered to be of minor importance.     

Evidence of Premeditation in Skin Messages in Suicide

A 34‐year‐old man with manic‐depressive disorder was found dead sitting in a vehicle with a hose running from the exhaust pipe to the cabin. Numerous suicide notes were found inside his house. At autopsy, the decedent was wearing jeans and a long‐sleeved windcheater. Upon removal of his clothes, a series of messages were also found written on the legs and forearm. Death was due to carbon monoxide toxicity with a blood level of carboxyhemoglobin of 84%. Skin messages represent a rare form of suicide note that may suggest that a suicide has not been planned, as the decedent may have used the nearest surface to write on. This case demonstrates, however, that skin messages may be more organized, being written prior to dressing and setting up the fatal episode. They also may compliment other notes and messages.     

一氧化碳中毒致死之案例研究

通过两例一氧化碳中毒致死特殊案例的分析,探讨一氧化碳中毒原因,中毒机理,中毒致死量。案例分析表明,只有通过详细认真的现场勘查,专业性的尸体检验及检材采取,科学的富有逻辑性的案件分析论断,才能准确为案件定性,解答死者家属疑问,以避免冤案错案的产生。     

Accuracy and Usefulness of the AVOXimeter 4000 as Routine Analysis of Carboxyhemoglobin

The measurement of blood carboxyhemoglobin (CO‐Hb) is important to determine the cause of death. The AVOXimeter 4000 (AVOX), a portable CO‐oximeter, has the advantages of a low purchase price and operating cost, ease of operation, and rapid results. Little information is available on the usefulness of AVOX in the forensic sample, and the previous study investigated only six samples. Therefore, in this study, we confirmed the usefulness of the AVOX through a comparison of its re s ults with data previously obtained using the double wavelength spectrophotometric method in autopsies. Regression analysis was performed between CO‐Hb levels measured by the AVOX and those measured by the conventional double wavelength spectrophotometric method in postmortem blood samples: a significant correlation was observed. This study suggests the usefulness of the AVOX to analyze postmortem blood, and the AVOX is suitable for routine forensic analysis and can be applied at the crime scene.