甲基苯丙胺致多巴胺能神经元毒性机制的研究进展

甲基苯丙胺属于苯丙胺类中枢兴奋剂,目前其滥用趋势严重。研究表明,甲基苯丙胺对动物及人类大脑纹状体多巴胺能神经元具有毒性作用。其毒性机制包括多巴胺信号转导影响和多巴胺的氧化作用、谷氨酸介导的兴奋性毒性作用、氧化应激和细胞因子的形成、线粒体功能紊乱、神经细胞凋亡、神经胶质细胞的活化以及高热等。但甲基苯丙胺对多巴胺能神经元的毒性机制并不完全清楚,本文结合文献对此进行综述,以期为相关研究提供参考。     

Characteristics and dose-effect relationship of clinical gamma-hydroxybutyrate intoxication: A case series

Gamma-Hydroxybutyrate (GHB) overdoses cause respiratory depression, coma, or even death. Symptoms and severity of poisoning depend on blood-concentrations and individual factors such as tolerance. A retrospective case study was conducted, evaluating GHB intoxication cases. GHB-concentrations in blood and urine were determined by gas chromatography-mass spectrometry (GC-MS) along with, in part, via enzymatic assay. GHB-concentrations, demographic data, and additional drug use, as well as specific clinical information, were evaluated. The correlation between GHB-levels in blood and associated symptoms were examined. In total, 75 cases originating from the Emergency Departments (EDs) of Hamburg and surrounding hospitals were included. Fifty-four of the patients (72%) were male. The mean GHB-concentration in blood was 248 mg/L (range 21.5–1418 mg/L). Out of the group with detailed clinical information (n = 18), the comatose group (n = 10/18) showed a mean of 244 mg/L (range 136–403 mg/L), which was higher than that of the somnolent and awake patients. Of the comatose collective, 70% (n = 7) showed co-use of one or more substances, with the additional use of cocaine being the most frequently detected (n = 5). In conclusion, a moderate dose-effect relationship was observed, although, there was some overlap in dosage concentration levels of GHB in awake and comatose patients. In GHB-intoxication cases, co-use was common as were clinical effects such as acidosis, hypotension, and impact on the heart rate. Timely analytical determination of the GHB-concentration in blood could support correct diagnosis of the cause of unconsciousness.     

肺组织缺氧时分子变化与机械性窒息死亡死因鉴定研究进展

肺是机体最大的呼吸器官,缺氧时肺组织细胞快速发生损伤性变化,同时激活自救通路,进而引发复杂的生物大分子变化。机械性窒息死亡是由机械性暴力引起的急性呼吸障碍导致的死亡。由于缺乏特异性的尸体内部征象,机械性窒息死亡的精准死因鉴定一直是法医病理鉴定的难点。本文回顾了缺氧条件下肺组织的生物大分子变化,探讨了将这些变化用于机械性窒息死亡精准死因鉴定的可能性,以期为相关研究提供新思路。     

磁性纳米颗粒在法医学痕量分析中的应用进展

鉴于法医学痕量分析中生物样本的复杂性以及目标物的痕量性,需要一种简单有效的方法从复杂基质中获得足量的目标物。磁性纳米颗粒(magnetic nanoparticle,MNP)凭借其独特的超顺磁性、稳定的物理化学性质、生物相容性、尺寸小、较高的比表面积等特性,已在生物医药、药物递送和药物分离等多个研究领域显现出广泛的应用价值。为了将MNP应用于法医检材的前处理,最大程度地增加目标物的提取率,尽可能减少干扰因素以满足目标物痕量分析要求,本文综述了近年来MNP在法医毒物分析、环境法医学、痕量物证分析和刑事侦查领域的应用进展,为MNP在法医学痕量分析中的应用提供研究思路。     

浓缩DNA法结合miniSTR分型技术检验微量DNA

目的优化低拷贝数DNA STR分型方法。方法对采用磁珠法或Chelex-100法提取DNA,Identi-filer试剂盒扩增,未获得分型结果的日常检案检材,采用物理浓缩法或过柱浓缩法浓缩DNA,采用miniFilerTM试剂盒再次扩增分型。结果 127例检材中,47例磁珠法提取DNA未获得分型的样品,分型成功率为36%;80例Chelex-100法提取DNA未获分型的样品,分型成功率为30%。结论采用浓缩法和miniFilerTM试剂盒,可以提高日常检案中低拷贝数检材的STR检验分型成功率。     

Dental hygiene students' matching accuracy when comparing antemortem dental radiographs and oral photographs to simulated postmortem WinID3® odontograms

Matching dental antemortem (AM) and postmortem (PM) data for human identification is especially challenging when the workforce is limited. Dental hygienists have served mass fatality incidents (MFIs) due to dental-related expertise. However, forensics within dental hygiene education and research on transferable skills is limited. This qualitative balance design study assessed senior dental hygiene students' match accuracy of simulated cases varying in dental identifiers based on AM full mouth series (FMS) radiographs and oral photographs to PM WinID3^® odontograms to demonstrate possible disaster victim identification (DVI) transferable skills gained during formal education. A convenience sample of senior dental hygiene students (n = 31) was presented information on WinID3^® interpretation, then presented with 5 mismatched cases and asked to visually interpret each to make 10 total matches; five based on AM FMS with simulated PM WinID3^® odontograms and five based on AM photographs with PM WinID3^® odontograms. Match accuracy scores ranged from 41.9% to 58.1% for cases with 1–10 identifiers, and 77.4% to 93.5% for cases with 11–40 identifiers. Accuracy when matching AM radiographs to PM odontograms versus AM photographs to PM odontograms was compared and revealed no statistical differences in match accuracy depending on image type (p = 0.388 to 1.000). Results of this pilot study suggests transferable match accuracy skills resulted from the participants' dental hygiene formal education. These baseline skills with additional specialized training support the rationale for dental hygienists serving on DVI teams. More research is needed in education and practice when preparing dental hygienists for forensic-based service.     

青岛地区汉族人群13个STR基因座的频率分布及法医学应用

目的　调查青岛地区汉族人群无关个体的 13个STR基因座 (D3S135 8、VWA、FGA、D8S1179、D2 1S11、D18S5 1、D5S818、D13S317、D7S82 0、D16S5 39、TH0 1、TPOX、CSFIPO)的基因频率分布 ,研究其遗传多态性及其在法医学个体识别及亲子鉴定中的应用价值。　方法　用美国ABI - 310型遗传分析仪对ProfilerPlus和Cofiler两个系统的 13个STR基因座的复合扩增产物进行毛细管电泳及四色荧光自动分析检测 ,基因分型软件为GeneScanv3.1和Genotyperv2 .5 .2。　 结果　获得 13个STR基因座在青岛地区汉族人群的基因频率分布数据 ,13个STR基因座的PIC >0 .5 ,DP >0 .71,CCE =0 .999999,TDP值接近 1,TPm =1.2× 10 -14 ,家系调查符合孟德尔遗传规律。　结论　ProfilerPlus和Cofiler两个系统的 13个STR基因座在法医学个体识别及亲子鉴定中具有较高的应用价值。     

SMART:自主研发的混合STR图谱分析系统

目的混合STR图谱的分析是法医遗传学领域的一个难题。目前国内大多数法医DNA实验室依靠人工方法分析混合STR图谱,费时费力,且拆分效果也多有主观性,难以满足日益增长的混合STR图谱分析的需求。本文介绍一套自主研发的混合STR图谱分析系统——SMART(STR Mixture Analysis and Resolution Tools),其能够实现对混合STR图谱的自动化分析,包括拆分混合STR图谱和计算似然比。方法SMART使用的STR峰高的概率模型,考虑了影子峰、降解、基因座特异性扩增效率、峰高变异、插入峰、峰丢失等因素。模型通过比较各个基因型集合拟合当前混合STR图谱的似然值大小来推断最有可能的基因型集合,采用了马尔可夫链蒙特卡洛(MCMC)算法进行求解。结果SMART可应用于不同试剂盒和遗传分析仪产生的数据。经使用ABI-3500XL遗传分析仪和Global Filer试剂盒测试,SMART能够实现对2~5人的混合STR图谱的分析,输出包括混合比例、混合图谱质量、各个贡献者单人的STR基因分型、似然比等多项结果。结论SMART作为一款自主研发的混合STR图谱分析系统,其基本涵盖了国外同类分析系统所具有的功能,技术性能指标达到国际先进水平,能够满足一线法医工作者对于混合STR图谱分析的多样化需求,提高混合STR图谱结果的利用率。     

耳廓的同一认定研究

目的研究耳廓观测指标的变化特征,提出利用耳廓特征识别点进行个体同一认定的研究方法,为法医学个体识别,及对视频图片中的个体进行同一认定,提供一种科学、准确、简便易行的方法。方法通过对19岁至22岁的汉族成人拍摄耳廓侧位图像,选取148人照片中的相应指标进行观测,数据收集,经SPSS统计软件处理,分析各种因素对测量结果的影响,计算出各指标识别能力及两批照片各指标之间的差值,最终得出各指标差值的参考值范围。结果 10项观测指标经统计检验分析,最终保留6项指标,重复测量结果稳定。各指标的变异系数相差不大,结果稳定可靠。结论通过制定6项观测指标差值的参考范围,确定指标是否同一,最终认定照片中耳廓是否属于同一个体的方法准确可行。     

基于分子克隆方法制备标准分子量片段混合物

目的制备标准分子量DNA片段混合物。方法选取pMD18-T载体部分序列作为插入片段,设计引物,制备包含不同大小的标准分子量片段的克隆。大量培养细菌提取质粒,用双酶切、连接荧光接头的方法制备不同大小的带有荧光的标准分子量片段,混合,纯化,最终获得标准分子量片段混合物(内标)。结果用分子克隆方法制备出具有实用性的标准分子量片段混合物,其单个标准分子量片段大小分别为80bp、124bp、194bp、224bp、254bp、304bp、349bp、399bp、424bp、454bp。并且这些标准分子量片段混合物可以准确地对DNATyper15试剂盒的扩增产物进行检测。结论应用该方法制备了能满足研究和实验室要求的标准分子量片段混合物,为DNA分子量标准物标准品的制作提供了一种新的方法。