Applicability of two commercially available kits for forensic identification of saliva stains

The RSID-saliva test and the SALIgAE-saliva test are two recently developed forensic saliva detection kits. In this study, we compared the sensitivity and the specificity of the two test kits with the Phadebas amylase test by analyzing amylases from various sources including human, animals, plants, and micro-organism. The data demonstrate that the RSID-saliva test and the SALIgAE-saliva test offer higher sensitivity and specificity for the detection of saliva than the Phadebas amylase test. The detection limits of the RSID-saliva test, the SALIgAE-saliva test, and the Phadebas amylase test equate to 10, 4, and 1000 nL, respectively for human saliva. The RSID-saliva test and the SALIgAE-saliva test were further evaluated by analyzing semen, vaginal secretion, breast milk, blood, urine, sweat, and feces. The results of the two tests are in good agreement. The two tests reacted with urine, breast milk, and feces, but not with semen, vaginal secretion, blood, and sweat.     

亲子鉴定STR突变的考虑

亲子鉴定中常会发生STR（short tandem repeats,短串联重复）突变的情况。突变对亲子关系的判定会造成困扰。对STR突变规律和亲子鉴定中所遇到的STR突变问题、突变的判定、突变下非父排除率和父权指数的计算以及需与突变区分的情形等问题进行综述和讨论。     

The Use of Hemastix® and the Subsequent Lack of DNA Recovery Using the Promega DNA IQTM System

Abstract:  Following implementation of our automated process incorporating the Promega DNA IQ^TM system as a DNA extraction method, a large number of blood-containing exhibits failed to produce DNA. These exhibits had been tested with the Hemastix^® reagent strip, commonly used by police investigators and forensic laboratories as a screening test for blood. Some exhibits were even tainted green following transfer of the presumptive test reagents onto the samples. A series of experiments were carried out to examine the effect of the Hemastix^® chemistries on the DNA IQ^TM system. Our results indicate that one or more chemicals imbedded in the Hemastix^® reagent strip severely reduce the ability to recover DNA from any suspected stain using the DNA IQ^TM magnetic bead technology. The 3,3',5,5'-tetramethylbenzidine (TMB) used as the reporting dye appears to interact with the magnetic beads to prevent DNA recovery. Hydrogen peroxide does not seem to be involved. The Hemastix^® chemistries do not interfere in any way with DNA extraction performed using phenol-chloroform. The incompatibility of the Hemastix^® chemistries on the DNA IQ^TM system forced us to adopt an indirect approach using filter paper to carry out the presumptive test.     

Developmental Validation of RSID™-Saliva: A Lateral Flow Immunochromatographic Strip Test for the Forensic Detection of Saliva

Abstract:  Current methods for forensic identification of saliva generally assay for the enzymatic activity of α-amylase, an enzyme long associated with human saliva. Here, we describe the R apid S tain ID entification (RSID™-Saliva), a lateral flow immunochromatographic strip test that uses two antisalivary amylase monoclonal antibodies to detect the presence of salivary amylase, rather than the activity of the enzyme. We demonstrate that RSID™-Saliva is accurate, reproducible, and highly sensitive for human saliva; RSID™-Saliva detects less than 1 μL of saliva. The sensitivity of RSID^TM-Saliva allows investigators to sample a fraction of a questioned stain while retaining the majority for DNA-STR analysis. We demonstrate that RSID™-Saliva identifies saliva from a variety of materials (e.g., cans, bottles, envelopes, and cigarette-butts) and it does not cross-react with blood, semen, urine, or vaginal fluid. RSID™-Saliva is a useful forensic test for determining which evidentiary items contain saliva and thus may yield a DNA profile.     

亲权指数计算的新方法

目的介绍一种亲权指数（paternity index,PI）计算的新方法。方法假定亲代的等位基因都要经过一个转变的过程才发生分离并遗传给子代。每个亲代的等位基因与子代相同时,其转变概率为1;当不相同时,其转变概率为0。且每个亲代的等位基因都有1/2的机会遗传给子代。据此,可以计算出孩子从争议父或母亲获得等位基因的概率。而随机男子提供等位基因给孩子的概率为等位基因频率。相应地算出PI值公式中的分子（X）和分母（Y）值。结果推导得到了一个能够计算三联体、二联体和失踪孩子案PI值的通用计算公式。结论本PI计算公式在亲子鉴定PI值计算上具有实用价值。     

Positive “Water Test”—An External Indicator of Base of Skull Hinge‐Ring Fracture

Abstract: Despite having significant internal injuries, victims of motor vehicle accidents may have surprisingly few external manifestations of trauma. The water test describes a technique whereby water placed in an upwardly facing ear results in drainage from the nose and opposite ear, thus demonstrating transcranial passage of water. This sign can be demonstrated in cases of blunt cranial trauma where there is a “hinge” fracture involving the petrous temporal bones bilaterally associated with a ring fracture extending around the foramen magnum posteriorly. Such a fracture results in separation of the posterior and middle cranial fossae providing a track for water to traverse. The water test provides a quick and noninvasive method for demonstrating the presence of a particular type of skull fracture.     

论客观关联共同侵权行为理论在中国侵权法上的确立

客观关联共同侵权行为理论的出现,是大陆法系侵权法在实用主义指导下连带责任适用范围通过"共同关系"理论进行扩张的必然产物,对数人侵权行为的法律责任体系产生了重大影响。我国侵权法上的"直接结合共同侵权行为"实质上就是客观关联共同侵权行为。客观关联共同侵权行为构成的因果关系要件应采"实质要素标准"。在因客观关联共同行为承担连带责任的成立范围上,应该受到"门槛"和"深度"的双重限制;在求偿程序上,应该"以按份责任为原则,连带责任为补充",赔偿权利人负有适当斟酌义务,并适用一次性请求限制规则。     

微波消解-扫描电镜联用检测脏器内硅藻

目的介绍一种微波消解-扫描电镜联用检测脏器内硅藻的新方法。方法大白兔30只,随机分为生前溺死组（n=15）和死后溺尸组（n=15）。提取兔肺、肝、肾、股骨骨髓和现场珠江水样,采用建立的微波消解-扫描电镜联用法检测脏器组织和水样中的硅藻,并与硝酸乙醇消解-扫描电镜联用的方法进行比较。结果生前溺死组的兔肺、肝、肾、股骨骨髓组织中大多数观测到与现场珠江水样一致的硅藻,微波消解-扫描电镜联用法检测脏器内硅藻的平均含量分别为：2505.2个/2g肺,18.7个/10g肝,6.5个/10g肾,6.3个/0.5g骨髓;肺与肝、肾、骨髓检出硅藻的阳性比例为86.7%,脏器硅藻检出含量和硅藻检验阳性比例均明显高于硝酸乙醇消解-扫描电镜联用法所测值。死后溺尸组的兔脏器组织均未观测到硅藻。结论微波消解-扫描电镜联用法检测脏器内硅藻,高效、安全、环保,硅藻检验灵敏度高,降低了劳动强度,提高了定性定量分析准确度,且能有效避免污染,在法医学溺死鉴定中具有良好的应用价值。     

菲德倍斯试剂检验唾液斑的有效性

目的验证菲德倍斯试剂（Phadebas Forensic tube test）检验唾液（斑）的有效性。方法从灵敏度、敏感性、常见载体的影响、唾液斑保存时间的影响,以及与STR检验的相关性等几个方面进行研究。结果0.01 ul唾液和阴干保存1年以上的唾液斑仍能被有效检出,该检验对其它常见体液（斑）反应不敏感,常见载体对该检验无影响。结论菲德倍斯试剂是人唾液（斑）检验的理想试剂。     

中国人群亲权鉴定常用STR基因座平均突变率的估计

目的对亲权鉴定中常用STR基因座在中国人群中的平均突变率进行估计,并与美国人群中的相应数据进行比较。方法突变数据来自按拟定标准筛选获得的15篇国内文献及本中心数据。对中国不同地区同一STR基因座突变率无显著差异的突变数据进行合并,计算中国人群该STR基因座的平均突变率,并采用Poisson分布的近似正态分布法计算该STR基因座平均突变率的95%可信区间。对中国人群和美国人群中常用STR基因座平均突变率的95%可信区间进行比较。结果 Identifiler和PowerPlex 16两个系统所包含的17个亲权鉴定常用STR基因座在中国不同地区人群中的突变率无显著差异,合并计算其平均突变率介于0.0120%～0.2078%,不同STR基因座的平均突变率差异显著（P〈0.0001）。这17个亲权鉴定常用STR基因座在中国人群中的累积突变率达到1.9836%。结论本研究通过文献分析获得中国大样本人群的FGA等17个STR基因座突变率数据,对于疑似突变案例的累积亲权指数计算具有借鉴价值。