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211.
Toby Vickar Katherine Bache Barbara Daniel Nunzianda Frascione 《Science & justice》2018,58(4):282-286
Collecting sufficient template DNA from a crime scene sample is often challenging, especially with low quantity samples such as touch DNA (tDNA). Traditional DNA collection methods such as double swabbing have limitations, in particular when used on certain substrates which can be found at crime scenes, thus a better collection method is advantageous. Here, the effectiveness of the M-Vac® Wet-Vacuum System is evaluated as a method for DNA recovery on tiles and bricks. It was found that the M-Vac® recovered 75% more DNA than double swabbing on bricks. However, double swabbing collected significantly more DNA than the M-Vac® on tiles. Additionally, it was found that cell-free DNA is lost in the filtration step of M-Vac® collection. In terms of peak height and number of true alleles detected, no significant difference was found between the DNA profiles obtained through M-Vac® collection versus double swabbing of tDNA depositions from 12 volunteers on bricks. The results demonstrate that the M-Vac® has potential for DNA collection from porous surfaces such as bricks, but that alterations to the filter apparatus would be beneficial to increase the amount of genetic material collected for subsequent DNA profiling. These results are anticipated to be a starting point to validate the M-Vac® as a DNA collection device, providing an alternative method when DNA is present on a difficult substrate, or if traditional DNA collection methods have failed. 相似文献
212.
Tawatchai Tanee Arunrat Chaveerach Runglawan Sudmoon Jatuporn Teanma Areerat Ragsasilp Prapaparn Sirikhansaeng 《环境索赔杂志》2018,30(2):131-141
This research studied accumulation of heavy metals in soil and three plant species in E-waste dumpsite in Kalasin Province, Thailand. DNA changes in the plants were accessed by DNA fingerprinting and genomic template stability (GTS) analyses. Concentrations of the metals were in the order of Zn > Pb > Cd > Cr. The Bioconcentration Factor (BCF), Translocation Factor (TF), and Enrichment Factor (EF) values showed that Typha angustifolia was suitable for phytoremediation of Cd, Pb, and Zn. However, after the process of phytoremediation, appropriate abolishment of the heavy-metal containing plants should be taken to prevent the metals from passing along the food web. The GTS values ranged from 54.23 to 69.35%. These results suggest that heavy metals have affected the genotoxicity of plants grown in the electronic waste dumpsite. 相似文献
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214.
目的探讨建立骨骼及牙齿DNA自动化提取的新方法。方法将33份骨骼及15份牙齿样本分别用冷冻研磨和手工处理两种方法研磨成粉,采用AutoMate ExpressTM自动化法医DNA提取系统提取DNA并定量。结果 AutoMate ExpressTM自动化法医DNA提取系统能够在3h左右完成骨骼、牙齿DNA的提取,两种方法处理的骨骼样本所得DNA质量浓度差异无统计学意义。冷冻研磨处理的骨骼和牙齿样本均获得了较好的STR分型结果,且牙齿样本所得DNA质量浓度高于手工提取所得。结论应用AutoMate ExpressTM自动化法医DNA提取系统是自动化提取骨骼、牙齿DNA的一种新方法,可应用于法医实际案件检验。 相似文献
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目的对M48磁珠法和Chelex-100法提取脱落细胞DNA的检验效果进行比较,为优化提取方法提供参考。方法选取案件受理检材50例烟蒂、50例纺织物品、50例作案工具,根据不同条件分别用吸附法、沾附法获得DNA,采用磁珠法(M48)和Chelex-100法提取后,常规STR检测。结果烟蒂类检材采用2种方法提取DNA,所得结果没有明显差异;纺织物品和作案工具上脱落细胞DNA的提取采用M48磁珠法提取的效果明显优于Chelex-100法。结论相对而言,M48磁珠法更具优势。 相似文献
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218.
同卵双生子(MZ)之间存在抗体库差异、甲基化修饰差异和基因突变体差异,甲基化修饰差异的比较可望成为甄别MZ的手段之一,抗体库差异和基因突变体差异比较的方法在甄别MZ方面亦有潜在价值.当前,对MZ的表现遗传以及基因突变等领域的研究还很有限,而抗体库技术的应用方法也有待探讨,因此MZ识别技术的应用前景和发展空间需要进一步摸索与完善. 相似文献
219.
以英美法系和我国司法实践中鉴定人角色差异为视野,深入探讨DNA证据应用领域中的三个经典命题的推导主体,明确鉴定人在DNA证据应用中的职责权限,避免DNA证据被错误解读和应用,并尝试以证据的相关性、可采性和证明力为基础,探讨我国司法实践中DNA证据正确应用的途径. 相似文献
220.
《Forensic Science International: Genetics Supplement Series》2013,4(1):e47-e48
Direct PCR is fast becoming a popular method in forensic science due to the advantages of saving time and money in the lab while increasing the probability of obtaining substantial results has a positive rippling effect. A laboratory is able to reduce the time spent on processing trace DNA samples, which can lead to investigators receiving important information in a timely manner that may not have been possible using standard methods. This study highlights the benefits of direct PCR in forensic casework by analysing trace and touch DNA on a range of substrates and exploring the loss of initial DNA due to extraction. 相似文献