OTS-2．2S基因芯片对人脑挫伤后基因表达差异的初步研究

目的利用基因芯片技术,研究人挫伤脑组织中基因表达差异。方法从脑组织提取mRNA,通过OTS-2.2S基因芯片,研究脑挫伤组织与对照脑组织细胞原癌及抑癌相关基因特异性表达差异。结果发现在挫伤脑组织中,HoJ-1和KIAAOO65基因表达水平显著下降,而p107mRNA表达水平显著升高。结论在脑挫伤中仅发现3条基因的表达有显著性差异;本研究是对脑损伤后基因表达水平及其法医学意义进行的探索性研究。     

Use of a Spray Device to Locate Touch DNA on Casework Samples

The use of a fluorescent dye to visualize cellular material on surfaces offers a targeted sampling approach for locating touch DNA on casework items. However, the current application of such dye is not feasible for examination of relatively large items. As a result, development of an efficient dye application system is required to translate this approach into practice. Here, the spray pattern (area covered, intensity, and evenness) of 15 different commercial spray devices was examined visually using food coloring. From this, five devices were selected to apply Diamond Nucleic Acid Dye (DD) to three substrates (glass slide, plastic sheet, and brown packing tape) seeded with saliva and touch DNA. The cellular material was visualized using the Dino-lite Microscope and Polilight. The inhibitory effects of DD afforded by each spray device were examined using Identifiler Plus^® DNA profiling kit and a DNA input of 800 pg. The two most promising devices were further tested on a range of mock casework items seeded with touch DNA. The results presented demonstrate the feasibility of a spray system to apply DD to large surfaces and subsequently detect cellular material at both micro and macroscale. Specifically, the data suggest that a pressurized continuous-spray system is favorable and that droplet size influences the intensity of fluorescence and surface coverage. Furthermore, this study indicates that full STR profiles can be obtained following spraying with DD solution, even with excessive application, which is essential for the widespread use of these devices in casework.     

A case of tri-allelic pattern at locus D3S1358 on chromosome 3p21 inherited from paternal grandmother

We are reporting a case of tri-allelic inheritance at locus D3S1358 commonly used for genetic identification in forensic DNA testing. This case was encountered during routine paternity testing using commercial DNA profiling kits. The tri-allelic inheritance identified was probably a result of duplication at this locus, supported by the equal peak intensities and inheritance pattern from grandparent to child.     

Evaluation of Commercial Kits for Dual Extraction of DNA and RNA from Human Body Fluids, ,

STR typing of DNA evidence can identify the donor with a high power of discrimination but cannot identify the tissue origin of a body‐fluid stain. Using RNA to attribute a crime scene stain to a particular tissue may aid in reconstruction efforts. With blood from 10 donors, four DNA and RNA coextraction kits were evaluated by measuring yields and STR and mRNA profiles. T tests indicated some significant differences in kit performance. The Zymo Research ZR‐Duet^? kit performed best based on average DNA (41.4 ng) and mRNA (4.07 ng) yields and was the only kit to provide complete DNA/RNA profiles for all samples. The consistency of this kit was challenged by data from additional blood and saliva donors. Further testing is advised before a superior kit is unequivocally chosen. Stand‐alone DNA or RNA purification generally offers higher yield, but coextraction may still allow successful STR profiling and tissue source identification.     

The Measurement of Stable Carbon Isotope Ratios of Eight Methamidophos Samples

Between December 2007 and January 2008, people suffered from food poisoning in the Japanese prefectures of Chiba and Hyogo after eating frozen dumplings (gyoza) produced in China, which had very high concentrations (1490–19,290 ppm) of methamidophos (O,S‐dimethyl phosphoramidothioate). Thus, we measured the stable carbon isotope ratio of methamidophos using GC/C/IRMS to identify the source. We analyzed seven methamidophos reagents and one Chinese agricultural methamidophos chemical (MTD600) that contained many impurities. The δ¹³C values of the seven methamidophos reagents and MTD600 ranged from ?49.23‰ to ?31.90‰, with an average SD of 0.20‰, very high precision. This difference (17.33‰) was very large compared with that in previous reports and may be attributable to the material itself and the chemical processing of methamidophos. Criminals can easily obtain pesticides such as methamidophos; therefore, it is very important to identify the pesticide source and distribution route using stable isotopic science in the future.     

犯罪心理画像历史发展评析

过去数十年里,犯罪心理画像(criminalprofiling)在国外的一些国家得到长足的发展,日显成熟,逐步成为侦查实践中不可或缺的一项侦查技术和法庭科学,而我国在这方面的研究甚少。本文通过查阅和编译国内外相关资料,从历史的角度重点论述犯罪心理画像的研究对象、在侦查中的运用、分类方法和发展历史,以期为加强犯罪心理画像在我国的本土化研究提供理论参考。     

法庭科学DNA实验室认可与质量控制

法庭科学DNA实验室认可是整个实验室认可活动的一个组成部分,是对法庭科学DNA实验室的质量管理水平和技术能力的一种国家及国际间的正式承认。本文从文件体系建立、测量溯源、方法的确认、能力验证、质量控制等5个方面,对DNA实验室在认可中存在的主要问题进行了分析,对法庭科学DNA实验室认可与质量控制进行了探讨。     

降解检材STR分型Ladder-Like条带形成原因的探讨

目的探讨降解DNA短串联重复序列PCR扩增产物在PAGE中Ladder-L ike条带的形成原因。方法用一组人工合成的不同长度的D8S1179DNA单链,模拟降解检材中的断裂DNA;利用John M设计的D8S1179引物对模拟模板的DNA单链进行PCR扩增,PAGE分离。结果不同模拟模板的DNA单链的组合可以扩增出不同的Lad-der-L ike条带。结论短串联重复序列Ladder-like条带是PCR过程中降解DNA多态区互补扩增的产物。     

在心理测试中犯罪心理画像的应用

犯罪心理画像作为一项将心理学和侦查相结合的技术,不仅对特定类型的案件侦破具有应用价值,在一般案件的侦破工作中,如果合理运用,同样能够发挥其应有的作用。     

Identifying background microbiomes in an evidence recovery laboratory: A preliminary study

16S rRNA profiling of bacterial communities may have forensic utility in the identification or association of individuals involved with criminal activities. Microbial profiling of evidence may, in the future, be performed within environments currently utilised for human DNA recovery, such as a forensic biology laboratory. It would be important to establish the background microbiome of such an environment to determine the potential presence of human or environmental microbial signatures to assist forensic scientists in the appropriate interpretation of target microbial communities. This study sampled various surfaces of an Evidence Recovery Laboratory (ERL) on three occasions including (a) before a monthly deep-clean, (b) immediately following the deep-clean, and (c) immediately after the laboratory’s use by a single participant for the purposes of routine item examinations. Microbial profiles were also generated for the involved participant and researcher for comparison purposes. Additionally, human nuclear DNA was profiled for each of the samples collected, using standard forensic profiling techniques, to provide a prospective link to the presence or absence of a background microbial signature within the ERL after its use. Taxonomic distributions across ERL samples revealed no consistent signature of any of the items sampled over time, however, major phyla noted within all ERL samples across the three timepoints were consistent with those found in human skin microbiomes. PCoA plots based on the Unweighted Unifrac metric revealed some clustering between participant microbial reference samples and surfaces of the ERL after use, suggesting that despite a lack of direct contact, and adherence to standard operating procedures (SOPs) suitable for human DNA recovery, microbiomes may be deposited into a forensic setting over time. The reference samples collected from the involved participant and researcher generated full STR profiles. Human DNA was observed to varying degrees in samples taken from the ERL across each of the sampling timepoints. There was no correlation observed between samples that contained or did not contain detectable quantities of human nuclear DNA and microbial profile outputs.