抗人Tf及抗人Hb试剂盒的比较

目的研究比较抗人Tf(转铁蛋白)和抗人Hb(血红蛋白)试剂盒的实验方法。方法采用胶体金标记单克隆抗体结合免疫层析技术,对不同稀释度的人血、动物血进行检测,并对保存时间、溶解度等影响因素进行研究。结果抗人Tf和抗人Hb试剂盒同样具有简单、快速、灵敏、稳定、特异性好的优点,但抗人Tf试剂盒能检测出陈旧及难以溶解血痕。结论抗人Tf试剂盒适用于法医物证的血痕种属检验。     

Lewis blood group determination in bloodstains by planimetric measurement of eluted monoclonal antibodies

Planimetric measurements were employed for reading the results of an elution test to determine Lewis blood groups in dry human bloodstains. In the absorption-elution test, two varieties of indicators were used to detect eluted Lewis antibodies. First, 64 blood-stains aged between 2 to 8 months were tested with glutaraldehyde (GLA)-treated erythrocytes (planimetric hemagglutination assay, PMHA). This method demonstrated that dry stains weighing approximately 0.4 mg (equivalent to 3 microliters of whole blood) were sufficient for detection of Lea or Leb antigen. Results were obtained within 1 h. Then, 37 of these stains were tested with Lewis substance-coated latex particles (planimetric latex agglutination assay, PMLA). The presence of Lea and Leb antigen were detected from dry stains weighing 0.1 mg (equivalent to 1 microL of whole blood) within 3 h. Both these assays are faster and simpler with accuracy than the enzyme-linked immunosorbent assay (ELISA). Latex particles coated with Lewis substance are, in particular, strongly agglutinated and show agglutination patterns more clearly than erythrocytes. The blind tests using these two methods properly classified 7 Le(a + b-) and 23 Le(a-b + ) bloodstains; whereas, 5 Le(a-b-) stains were undetermined by the criteria for these tests. These results indicate the usefulness of the PMHA and PMLA for typing Lewis blood groups from small bloodstains.     

The evaluation of five electrophoretic phenotyping systems for routine screening of bloodstains

The performance of the polymorphic marker systems group-specific component (GC), phosphoglucomutase-1 (PGM), alpha-2-HS-glycoprotein (A2HS), haptoglobin (Hp), and erythrocyte acid phosphatase (EAP) was evaluated on control bloodstains. The major factors considered were: sensitivity of the test system; stability of the marker; laboratory economics of each test; and distinguishing power (Dp) of the system. GC was considered to be the most suitable marker for routine screening because of its high stability and Dp, and the sensitivity of the immunoblotting detection method. PGM and A2HS were the next most valuable markers followed by Hp. EAP could only be considered useful when large amounts of relatively fresh bloodstain were available.     

An efficient method to eliminate streaking in the electrophoretic analysis of haptoglobin in bloodstains

A bloodstain extraction procedure that improves the analysis of haptoglobin in dried bloodstains has been developed. The streaking of electrophoresis gels caused by deteriorated hemoglobin can be eliminated by incorporating chloroform in the bloodstain extraction procedure. The method is easier to execute than previously published techniques for eliminating the adverse effects of deteriorated hemoglobin on the analysis of haptoglobin. Bloodstains up to two years old were correctly phenotyped in haptoglobin by this method.     

A blind trial evaluation of a crime scene methodology for deducing impact velocity and droplet size from circular bloodstains

In a previous study, mechanical engineering models were utilized to deduce impact velocity and droplet volume of circular bloodstains by measuring stain diameter and counting spines radiating from their outer edge. A blind trial study was subsequently undertaken to evaluate the accuracy of this technique, using an applied, crime scene methodology. Calculations from bloodstains produced on paper, drywall, and wood were used to derive surface-specific equations to predict 39 unknown mock crime scene bloodstains created over a range of impact velocities (2.2-5.7 m/sec) and droplet volumes (12-45 microL). Strong correlations were found between expected and observed results, with correlation coefficients ranging between 0.83 and 0.99. The 95% confidence limit associated with predictions of impact velocity and droplet volume was calculated for paper (0.28 m/sec, 1.7 microL), drywall (0.37 m/sec, 1.7 microL), and wood (0.65 m/sec, 5.2 microL).     

试论影响死刑适用的几个因素

死刑是一种最严厉的刑罚方法.如果说理论工作者还只是抽象地谈论死刑的严厉性的话,那么法官在具体适用死刑时不仅要直接面对即将被剥夺生命的被告人,而且还要面对由于死刑判决的不可逆转而带来的心理压力.然而从司法实践来看,死刑的裁量仍存在诸多难以令人满意的地方.其突出表现一是在司法实践中死刑的裁量存在过多、过滥的问题;二是死刑的裁量存在案件不平衡、时间不平衡、地区不平衡的问题.造成死刑裁量过多过滥及量刑不平衡的因素是多方面的,笔者拟选择其中三个主要的因素加以分析,并就教于学者同仁.     

混合血迹中不同个体成份逐一分离识别的研究

目的研究法庭科学混合血迹物证中不同个体成份逐一分离、识别的问题,建立适合混合血迹个体识别的分析技术。方法采用PCR-SSCP及测序技术,选择m tDNA D-loop区的HVI 16030~16481区域452 bp片段作为分析目标,对中国汉族两无关个体、三无关个体混合血迹进行分析。结果100份两个体混合血迹样品m tDNA 452bp的PCR产物经SSCP电泳分离,结果有95份样品完全分离开,分离成功率达95%;30份三个体混合血迹样品452 bp片段经SSCP电泳分离,结果有26份样品有1~3个个体完全分离开,分离成功率达84%。对其中3份两个体混合血样、2份三个体混合血样SSCP电泳分离后的谱带进行回收、测序分析,两个体混合血样每一份均可准确获得其中单一个体序列及以另一个体主要成份(峰值比达4∶1以上)的序列结果;三个体混合血迹中不同个体成份可以达到初步分离,1份可准确确定单一个体序列。对两个体不同比例混合样品SSCP分析,结果可以检测到较少成份的最低比例为20∶80。结论本研究建立的PCR-SSCP及测序分析混合血迹综合技术,是对混合血迹中不同个体成份逐一分离、识别的一种有效技术手段。     

Determination of the age of bloodstains using immunoelectrophoresis.

The technique of immunoelectrophoresis was used to determine the age of bloodstains. The immunoelectrophoretic patterns (IEP) of bloodstains ranging from 15 days to one year old were obtained by the use of high titer anti-whole human serum. The IEPs revealed gradual disappearance of beta-globulins and gamma-globulin with increase in the age of bloodstains. A comparative study of the IEP of normal human serum with those of the experimental bloodstains showed the absence of some of the corresponding proteins. The absence of a particular serum protein in the IEP of a given bloodstain will indicate the age of that bloodstain.     

Sensitive fluorometric detection of heat-stable alkaline phosphatase from bloodstains for the forensic diagnosis of pregnancy

Sensitive and simple procedures are established for the forensic pregnancy test from bloodstains. This paper describes new techniques based on heat stability of placental alkaline phosphatase. In this study the total and heat-stable alkaline phosphatase activities were determined using 4-methylumbelliferyl-phosphate as substrate. The ratio of heatstable alkaline phosphatase to total alkaline phosphatase was calculated. A more simple screening test which was visible by exposure to UV light is described. These may be helpful in the diagnosis of pregnancy from only a slight bloodstain.     

吸附性载体上微量血痕的DNA分型

目的研究吸附性载体上微量血痕的DNA提取及其检验。方法用Chelex-100法、QIAamp MiniKit、及QIAamp Mini Kit改良法提取吸附性载体上微量血痕中的DNA,进行PCR扩增及STR检验。结果采用Chelex-100法及QIAamp Mini Kit的分型成功率很低;采用QIAamp Mini Kit的改良法能较好的得到分型图谱。结论采用QIAamp Mini Kit的改良法能较好的提取吸附性载体上微量血痕的模板DNA。     

Errors in the determination of the point of origin of bloodstains

Bloodstain pattern analysts are sometimes called upon to determine the point of origin of a pattern of bloodstains. A derivation of expressions for the uncertainties deltaX and deltaY in the coordinates of the point of origin P(X, Y) of two bloodstains on a surface has recently been published. These uncertainties were expressed in terms of the uncertainties in the measured distance between the bloodstains and the uncertainties in the angles of impact of the bloodstains. This paper extends the derivations in the previous work by expressing the uncertainties in the coordinates of the point of origin of two bloodstains in terms of the uncertainties in the length and width measurements from which the angles of impact of the bloodstains are calculated.