Nitrous Oxide Determination in Postmortem Biological Samples: A Case of Serial Fatal Poisoning in a Public Hospital*

Abstract: In a public hospital, eight cases of fatal poisoning by nitrous oxide (N₂O) occurred under oxygen administration, due to an erroneous swapping of the lines in the gas system. The aim of the study was to clarify the factors involved in asphyxia by characterizing gases from different lines and measuring N₂O concentrations in postmortem biological samples from bodies exhumed. Analyses carried out on the gas system confirmed the erroneous substitution of O₂ line with N₂O and air line with O₂. Consequently, high N₂O amounts were revealed in several tissues and gaseous biological samples. All specimens were analyzed by headspace gas chromatography technique. A rigorous quantitative analysis was possible only in blood (11.29–2152.04 mg/L) and urine (95.11 mg/L) and in air samples from stomach and trachea (from 5.28 to 83.63 g/m³). This study demonstrates that N₂O can be detected in biological samples even 1 month after death.     

论强制采样侦查手段的法制化

强制采样作为一种特殊的侦查手段,在刑事案件的侦查中发挥着不可忽视的作用。考察我国现阶段有关强制采样的相关规定以及在进行强制采样侦查过程中所出现的问题,我们不难发现强制采样侦查手段的实施和法律规制已出现了相当棘手的问题。结合域外的司法实践,我们只有对强制采样侦查手段予以法定化、程序化、制度化,才能使其更好地发挥作用,更有力地打击各种刑事犯罪活动。     

生物检材中乌头碱的LC-MS/MS快速分析

目的应用高效液相色谱-质谱法对生物检材中乌头生物碱等有毒成分进行快速分析。方法取全血样品经乙腈-甲醇(5:1 v/v)提取,使用Agilent Zorbax SB C18(2.1 mm×50 mm,1.8μm)色谱柱,以0.1%甲酸溶液-乙腈(60:40 v/v)为流动相等度洗脱。在多反应监测模式下测定全血样品中乌头生物碱等有毒成分。结果乌头碱、次乌头碱和中乌头碱的保留时间为0.73 min、0.77 min和0.63 min;用于定量分析的离子对分别为m/z 646.4→586.4(乌头碱)、616.1→556.5(次乌头碱)和632.4→572.1(中乌头碱)。乌头碱在0.1~250 ng/m L内线性关系良好,相关系数(r)≥0.9987,最低检出限0.1ng/m L,精密度考查其变异系数(CV)5.42%(n=6),血液中乌头碱提取回收率不小于90%。结论本文建立的高效液相色谱-质谱法快速、简便、灵敏,适用于天然药毒物检验。     

The Portuguese adaptation of the Gudjonsson Suggestibility Scale (GSS1) in a sample of inmates

This paper comprises two studies which address the validity of the Portuguese adaptation of the Gudjonsson Suggestibility Scale, GSS1. In study 1, the means and standard deviations for the suggestibility results of a sample of Portuguese inmates (N = 40, M_age = 37.5 years, SD = 8.1) were compared to those of a sample of Icelandic inmates (Gudjonsson, 1997; Gudjonsson & Sigurdsson, 1996). Portuguese inmates' results were in line with the original results. In study 2, the means and standard deviations for the suggestibility results of the sample of Portuguese inmates were compared to those of a general Portuguese population sample (N = 57, M_age = 36.1 years, SD = 12.7). The forensic sample obtained significantly higher scores in suggestibility measures than the general population sample. ANOVA confirmed that the increased suggestibility in the inmates sample was due to the limited memory capacity of this latter group. Given that the results of both studies 1 and 2 are in keeping with the author's original results (Gudjonsson, 1997), this may be regarded as a confirmation of the validity of the Portuguese GSS1.     

建立火场样品中汽油残留物ATD-GC-MS检验结果的评价方法

目的建立火场中汽油燃烧残留物ATD-GC-MS检验结果评价方法。方法将模拟燃烧样品用ATD-GC-MS法检验,检验结果通过对芳烃、烷烃、茚满、和萘系列的4个特征离子色谱图与已知汽油作比较,并利用向量夹角法计算样品与汽油色谱指纹图的相似度来对检验结果作评价。结果有汽油作助燃剂的模拟燃烧样品与汽油色谱指纹图的相似度一般大于90%,无汽油作助燃剂的样品则在60%以下。结论利用样品的4个特征离子色谱图与已知汽油作比较,并结合样品与汽油色谱指纹图相似度的计算,能对检验结果作出客观、可靠和准确的评价。     

Beyond the “Narrow Data Base”: Another Convenience Sample for Experimental Research

The experimental approach has begun to permeate political science research, increasingly so in the last decade. Laboratory researchers face at least two challenges: determining who to study and how to lure them into the lab. Most experimental studies rely on student samples, yet skeptics often dismiss student samples for lack of external validity. In this article, we propose another convenience sample for laboratory research: campus staff. We report on a randomized experiment to investigate the characteristics of samples drawn from a general local population and from campus staff. We report that campus staff evidence significantly higher response rates, and we find few discernible differences between the two samples. We also investigate the second challenge facing researchers: how to lure subjects into the lab. We use evidence from three focus groups to identify ways of luring this alternative convenience sample into the lab. We analyze the impact of self-interest, social-utility, and neutral appeals on encouraging study participation, and we find that campus staff respond better to a no-nonsense approach compared to a hard-sell that promises potential policy benefits to the community or, and especially, to the self. We conclude that researchers should craft appeals with caution as they capitalize on this heretofore largely untapped reservoir for experimental research: campus employees.

芪白平肺胶囊通过抑制PI3K/Akt通路促进低氧大鼠肺动脉平滑肌细胞凋亡

目的 从细胞水平探讨芪白平肺胶囊通过磷脂酰肌醇3激酶(phosphatidylinositol 3-ki-nasePI3K/蛋白激酶B(protein kinas B,Akt)通路对低氧诱导的大鼠肺动脉平滑肌细胞(pulmona-ry arterial smooth muscle cells,PASMCs)凋亡的影响....     

Results of the 2003–2004 GEP-ISFG collaborative study on mitochondrial DNA: Focus on the mtDNA profile of a mixed semen-saliva stain

We report here a review of the seventh mitochondrial DNA (mtDNA) exercise undertaken by the Spanish and Portuguese working group (GEP) of the International Society for Forensic Genetics (ISFG) corresponding to the period 2003–2004. Five reference bloodstains from five donors (M1–M5), a mixed stain of saliva and semen (M6), and a hair sample (M7) were submitted to each participating laboratory for nuclear DNA (nDNA; autosomal STR and Y-STR) and mtDNA analysis. Laboratories were asked to investigate the contributors of samples M6 and M7 among the reference donors (M1–M5). A total of 34 laboratories reported total or partial mtDNA sequence data from both, the reference bloodstains (M1–M5) and the hair sample (M7) concluding a match between mtDNA profiles of M5 and M7. Autosomal STR and Y-STR profiling was the preferred strategy to investigate the contributors of the semen/saliva mixture (M6). Nuclear DNA profiles were consistent with a mixture of saliva from the donor (female) of M4 and semen from donor M5, being the semen (XY) profile the dominant component of the mixture. Strikingly, and in contradiction to the nuclear DNA analysis, mtDNA sequencing results yield a more simple result: only the saliva contribution (M4) was detected, either after preferential lysis or after complete DNA digestion. Some labs provided with several explanations for this finding and carried out additional experiments to explain this apparent contradictory result. The results pointed to the existence of different relative amounts of nuclear and mtDNAs in saliva and semen. We conclude that this circumstance could strongly influence the interpretation of the mtDNA evidence in unbalanced mixtures and in consequence lead to false exclusions. During the GEP-ISFG annual conference a validation study was planned to progress in the interpretation of mtDNA from different mixtures.     

HS/GC/ECD分析生物检材样品中的氰化物

目的 建立生物样品中氰化物的衍生化定性定量分析方法。方法 用氯胺T衍生化,HS/GC/ECD分析衍生物CICN。结果 在1ml血中,添加0.2μg氰化钾,回收率为84.6％,RSD为6.39％;在1g肝中添加0.5μg氰化钾,回收率为67.3％,RSD为5.05％;血中检出限为5ng/ml。结论 所建方法能定性定量分析生物样品中的氰化物。     

笔迹样本及提取技巧

在笔迹检验中,笔迹样本是否可靠、充分、具有可比性,直接关系到鉴定结论准确与否。如果提取的样本不符合鉴定要求,即使找准了嫌疑对象,也难以做出同一认定结论。如何提取符合鉴定要求的笔迹样本,作者参考有关文献,结合二十年来在基层从事笔迹检验实践的体会,研究探讨了笔迹样本的种类、条件及提取技巧。以期为文检同行及公检法办案人员抛砖引玉。