An analysis of data curated from 5 years of identifying human remains

An archive of 5 years of cases involving the identification of human remains was curated, collecting information on: The sample type submitted, the number of STR loci yielding interpretable results, the kinship challenge posed, and the outcome for the case. A total of 129 cases of remains ID were investigated using manual DNA extraction and recovery methods with amplification of STR markers using the Power Plex 21 multiplex STR kit from Promega Corp. In 52 cases, blood spots collected by the ME were provided as sample and in 100% of those cases, probabilities of relatedness to the reference samples was ≥99%. In 77 cases, tissue other than blood was provided as a source of DNA. These other samples were grouped categorically into long bones (femur and tibia; 40 cases), skull bones/teeth (11 cases), other bones (16 cases), and tissue (normally adherent to bone) (10 cases). Reference samples provided for cases included alleged parents or child(ren) of the victim (86 cases), alleged full siblings of the victim (38 cases), or alleged second-order relatives (five cases). The overall success rate in confirming the identity of the source of the remains in these cases was 89.2%. Our results demonstrate that a laboratory can be often successful identifying human remains using methods easily implemented in any DNA typing laboratory.     

3种骨骼DNA提取方法的应用效果比较

目的对3种方法提取骨骼DNA的效果进行比较,为实际应用中选择方法提供参考。方法应用骨骼孵化液法、DNA Investigator试剂盒法和CTAB法对同一骨骼样本进行脱钙、消化、提取DNA,用紫外分光光度计检测DNA的浓度值;使用Identifilerplus试剂盒进行PCR扩增,3130xl型遗传分析仪检测分型,并用SPSS 19.0软件对各项实验结果进行统计分析。结果 1g骨粉样本经上述3种方法提取,得到的DNA浓度分别为26.53ng/μL±5.47ng/μL、23.63ng/μL±4.56ng/μL、14.93ng/μL±3.88ng/μL;单因素方差分析表明3组数据之间差异性具有统计学意义。PCR扩增后电泳检测结果显示,骨骼孵化液法和DNA Investigator试剂盒法基因座检出率和峰值大致相同,均优于CTAB法。结论本文比较的3种方法均可用于骨骼样本的实际检案,检出率较高的两种方法可作为优选方案。     

The effect of NucleoSpin® Forensic Filters on DNA recovery from trace DNA swabs

Forensic DNA profiling is a globally accepted method for human identification, however, obtaining full DNA profiles from trace DNA can be challenging. The optimal recovery of DNA from trace DNA swabs is therefore crucial. Methods for extracting DNA from swabs often make use of a spin basket combined with a centrifugation step, to enhance the release of cells from the swab prior to DNA extraction. The NucleoSpin® Forensic Filter (Macherey-Nagel, Düren) is a type of spin basket, but it has not been thoroughly assessed on trace DNA samples. This study aimed to assess if the inclusion of the NucleoSpin® Forensic Filter significantly improved DNA recovery and DNA profiling success from cotton and flocked swabs used to collect trace DNA and buccal cells (control). Buccal cells and trace DNA samples were collected from 25 volunteers using each swab type (cotton and flocked) in duplicate. DNA was extracted from the samples using the NucleoSpin® DNA Forensic kit, one set with, and the other set without, NucleoSpin® Forensic Filters. DNA concentration was assessed using real time PCR, and DNA profiling was done using the PowerPlex® ESX 16 system. The inclusion of the NucleoSpin® Forensic Filters significantly improved DNA concentration for buccal cells that were collected using flocked swabs (p = 0.035). However, no significant differences were noted for trace DNA samples for either swab type. There was also no significant difference in DNA profiling success when NucleoSpin® Forensic Filters were used, regardless of swab and sample type. These results may be helpful for laboratories that are considering the NucleoSpin® Forensic Filters in the DNA extraction workflow, particularly for trace DNA samples.     

Combined DNA Typing and Protein Identification from Unfired Brass Cartridges,,,

Biological evidence analysis from contact traces is adversely affected by low quantity and quality of DNA. Proteins in these samples contain potentially individualizing information and may be particularly important for difficult surfaces such as brass, where DNA may yield incomplete profiles. In this study, touched unfired brass cartridges were sampled using dry tape or wet swabs and analyzed by separating DNA and protein from the same collected material, thus producing both genomic and proteomic information. DNA recovery was similar for both collection methods, with tape yielding an average of 1.36 ± 1.87 ng and swabs, 1.34 ± 3.04 ng. Analysis by mass spectrometry identified 95 proteins, with the two collection methods showing no significant difference (p = 0.76) in the average number of collected proteins: 44.5 ± 10.9, (tape) versus 47.9 ± 20.4 (swabs). Proteins can be collected from fingerprints at levels necessary to provide identifying information, thus expanding information obtained from challenging evidence.     

Implementation of Prep-n-Go™ Buffer for DNA extraction from buccal swabs

The efficacy of two extraction methods; room temperature and heat protocols was assessed for buccal swabs using the Prep-n-Go™ Buffer. DNA was extracted from buccal swabs using both extraction methods and their effectiveness to produce good quality DNA profiles was evaluated. Heat protocol was found to yield more DNA, however room temperature protocol produced better quality DNA profiles with fewer artefacts when the samples from both extraction methods were amplified directly without any normalisation with the VeriFiler™ Express PCR Amplification Kit.     

室外温度与室内恒温下EC随死后经历时间的变化

目的在室外环境和室内恒温条件下测定昼夜不同时间猪后腿肌肉电导率(electrical conductivity,EC)值,分析并比较两种环境条件下,EC值随死后经历时间(time since death, TSD)变化的规律。方法取5块即刻屠宰的猪后腿肌肉,均分为两份,随机分成两组,分别置于秋季室外环境和室内18℃恒温环境中。在死后10d内分别于早晚8时(每隔12h)取样,测定其浸渍液EC值。结果两种环境条件下,EC随TSD变化的趋势在整体上是一致的,二者相关性均较好(R2室外=0.971,P室外=0.004,R2室内=0.98,P室内=0.002)。室外环境温度下,肌肉的EC值在白天增长明显,夜间增长不明显,尤其环境温度低于13℃时,出现明显的平台现象,与室内恒温条件下肌肉EC值持续上升的变化趋势有显著的差异。结论无论室外环境温度还是室内恒温下,肌肉EC与TSD的相关性均较好,但在具体分析时,应考虑到夜间低温平台期造成的时间延搁。     

组织切片DNA提取的探讨

在医患关系纠纷中,病理组织切片经常被作为至关重要的证据,但对它的检验是目前法医DNA检验的难点。因样本制作固定的时间、保存环境等不同因素的影响,病理组织切片DNA检出率并不高。本文从实际检案角度出发,详细介绍了病理组织切片DNA提取的过程,并分析了其可能影响因素。     

正交设计优选黄芩栀子合煎工艺

目的 正交设计优选黄芩栀子合煎工艺。方法 采用正交试验法,考察加水量、煎煮时间、煎煮次数对黄芩、栀子合煎液中栀子苷含量、黄芩苷含量及干膏得率的影响。结果 优选出的最佳提取工艺为：加8倍量水,提取3次,每次0.5 h。结论 所优选的工艺稳定、合理、可行,可为合理开发含有黄芩、栀子药对的复方制剂提供理论依据。     

正交试验法优选复方白芍颗粒提取工艺

目的 优选复方白芍颗粒的最佳提取工艺。方法 以干膏得率和白芍活性成分芍药苷的提取率为评价指标，采用正交设计法考察溶剂用量、提取时间以及提取次数对提取结果的影响，确定最佳提取工艺。结果 最佳提取工艺参数为：加10倍量水，提取2次，每次提取1 h。结论 优选的提取工艺切实可行，为复方白芍颗粒制剂的研究奠定基础。     

藤黄中新藤黄酸提取分离工艺改进

目的 改进从中药藤黄中提取、分离新藤黄酸的工艺。方法 按正交试验法优选提取工艺，以乙醇为提取溶剂，并采用AB-8大孔树脂富集，硅胶柱湿法上样，流动相（石油醚∶乙醇=20∶1）洗脱，分离得到纯化的金黄色化合物。运用熔点测定、紫外光谱、红外光谱、质谱和核磁共振技术，通过与文献数据比较来确证化合物结构。结果 金黄色化合物的熔点、紫外光谱、红外光谱、质谱、1H 核磁共振谱（nuclear magnetic resonance, NMR）、13C-NMR数据与文献中新藤黄酸的相应数据一致。结论 运用改进的工艺从藤黄中提取分离新藤黄酸是可行的，更利于工业化生产。