Improving the point of origin determination in bloodstain pattern analysis

In bloodstain pattern analysis, it is important to know the point of origin (PO) of an impact pattern. This point can be estimated by means of the stringing method, the tangent method, or by commercially available computer programs. In this study, the accuracy of two computer programs was investigated under different conditions. Impact patterns were created by means of a modified mouse trap, and subsequently the PO was calculated. By examining the characteristics of single bloodstains, the influence on the deviation could be determined. To improve the estimation of the PO, it is important to select bloodstains that lie close to the presumable location of the blood source, that are large (width >1.5 mm) and that show an elliptical form. If possible, bloodstains from different walls should be taken into account. Our recommendations may improve the PO determination of impact patterns.     

Immunochemical and chromatographic determination of ABH antigens in compact bone tissue

The identification of ABH antigens from compact bone tissue is known from many sources. The purpose of this study was to make a contribution to the localization of blood-group-active substances in compact bone tissue. A variety of preparation and identification methods were successfully used and compared. Samples were extracted from compact bone tissue, separated by HPTLC, and examined using the absorption-elution and PAP techniques. Additionally, the PAP technique was carried out on cryostat sections. Serologically active blood-group substances were consistently demonstrated in the organic components of the haversian canals.     

Evaluation of antisera for bloodstain grouping. I. ABH, MN, and Rh

Sixty-eight different commercially available blood grouping antisera and lectins with ABH, MN, and Rh D, C, E, c, and e specificities were serologically evaluated for their applicability to bloodstain antigen determination. The characteristics of the antisera were determined with red cells, with fresh bloodstains, and with series of aging bloodstains. The Rh antisera were tested under a variety of serological conditions and with bloodstains on various substrata. Additionally, studies on optimization of absorption-elution procedure variables were carried out, and some data on the storage characteristics of red cells and blood grouping antisera were gathered.     

An experimental study of the identification of the person of origin of a bloodstain by crossed immunoelectrophoresis

Crossed immunoelectrophoretic (CIEP) patterns were examined for the purpose of individualization of bloodstains. For comparison the areas of peaks were measured and ratios of the areas of corresponding peaks were calculated. To assess the dispersion of the ratios, the coefficient of variation (CV) was calculated as CV = 100 X standard deviation/mean of ratios. With 1-month-old bloodstains there were significant differences in the distributions of CV between the groups of the same and those of different origin. These results indicate that CIEP is useful as a means of identifying the origin of bloodstains.     

Immunocytochemical determination of ABH and MN antigens on dried blood traces in the nanoliter range.

The absorption-elution test and the mixed cell agglutination reaction are both ultimately based on the ability of indicator cells to agglutinate. This agglutination reaction requires a relatively large amount of antigenic epitopes, and, in addition, a relatively high volume of blood traces. The immunocytochemical demonstration of epitopes requires a lower volume, which, however must be fixed for investigation, thus possibly causing damage to the epitopes and thereby preventing detection. An immunocytochemical method is presented which permits ABH and MN antigen determination on dried blood traces of nanoliter quantities without special fixation. This method is based on immunocytochemical demonstration of antigens directly on the cell membrane in combination with the use of a coated glass slide that ensures maximum economy of epitopes.     

Cytochemical detection of ABH antigens in human body fluids

The use of the peroxidase-anti-peroxidase (PAP) technique has been described previously for the detection of cellular antigens and in particular ABO antigens from tissue samples (Pedal and Hülle 1984; Pedal and Baedeker 1985; Pedal et al. 1985). In this survey, the PAP method has been employed to study the detection of ABO antigens in cells from body fluids of particular interest to forensic science, namely buccal cells and vaginal cells. Also tested, but in a limited number, were mixtures of body fluids and semen samples. No false reactions were obtained from buccal cells, all samples corresponding to the ABO blood type of the donor. Preliminary results from vaginal cells, vaginal/buccal cell mixtures, and semen were encouraging but must be treated with caution due to the limited number tested. Vaginal smears contaminated with semen showed varying degrees of nonspecificity.     

ABH and Lewis antigens in the tracheal glands. I. Lewis-positive individuals

Antigens A, B, H, Lea, and Leb were demonstrated in the tracheal glands of 15 Lewis-positive secretors and 15 nonsecretors by the indirect immunoperoxidase technique. The detection of group-specific ABH antigens in mucous epithelium and intraductal secretory fluid was dependent on the secretor character. Whereas determination of secretor character was sometimes unreliable with anti-A and anti-B, the findings obtained by additional labeling with UEA1 were consistently correct. The secretors showed minimal gland labeling with anti-Lea and intensive labeling with anti-Leb; the nonsecretors, intensive Lea labeling and weaker or absent Leb labeling. Consequently, the determination of secretor character by ABH labeling could be verified by the behavior of the Lewis antigens. Since both morphologic structures and epithelial antigens are highly resistant to putrefaction, ABO and secretor character can also be diagnosed in badly decomposed tracheal wall specimens.     

多种遗传标记在同母异父半同胞关系鉴定中的综合应用

目的通过对常染色体和X染色体STR基因座以及线粒体DNA高变区多态性的检验,探讨同母异父半同胞关系鉴定策略。方法提取3名全同胞及其1名疑似同母异父半同胞个体的DNA,采用SinofilerTM试剂盒检测常染色体上的15个STR基因座、采用Mentype Argus X-8试剂盒和自主研制的16重X染色体STR扩增体系,共检验X染色体上的19个STR基因座,同时采用基因测序技术分析线粒体DNA高变区Ⅰ和高变区Ⅱ的多态性。结果依据常染色体STR基因型结果及全同胞指数和半同胞指数计算结果排除可疑个体与已知3名全同胞间存在全同胞关系,线粒体DNA高变区多态性检测结果提示4名被鉴定人为同一母系,X染色体STR分型结果支持被鉴定个体间为半同胞关系。结论对于同母异父半同胞鉴定案例,综合运用常染色体STR、X染色体STR及线粒体DNA高变区测序等多种遗传分析手段,可获得可靠的鉴定结论。     

Detection of glycosphingolipids of ABH and Le antigens on thin-layer plates using the PAP method

Stroma from hemolyzed erythrocytes of blood groups 0, A1, B and A1B were obtained and subjected to butanol/phosphate buffer extraction. This extract was separated using HPTLC, and the ABH and Le substances were detected on the chromatogram using the PAP technique. The staining of the bands allowed specific demonstration of the serologically active glycosphingolipids present in the ABH and Le blood group substances. The antigens of the AB0 system showed a 3- to 12-band pattern. Each of the antigens Lea and Leb presented 3 bands. The slight differences in the levels of glycosphingolipids of equal chain lengths are probably due to differences in their chemical structures.     

ABH and Lewis antigens of tracheal glands. II. Lewis negative individuals

Immunocytochemical studies were performed on tracheal wall samples embedded in paraffin; the samples were taken at 23 autopsies. In all cases, the red cells had been typed in postmortem serological studies as being Le(a-b-). Blood-group antigens were demonstrated by the indirect immunoperoxidase technique, using monoclonal Anti-A, Anti-B, Anti-Lea and Anti-Leb; H was detected by UEA 1. The secretor characteristics could clearly be diagnosed from the ABH staining pattern of the mucous glands. In 11 cases, the lewis antigen labeling patterns were identical to the group of Lewis-positive individuals. It seems probable, from the statistical point of view, that these 11 individuals were, in fact, Lewis-positive and that the negative serology resulted from deterioration of the cadaver blood samples. The immunocytochemistry was quite different in the remaining 12 cases: (a) secretors (n = 9) were completely negative for Lea, Leb was equally negative in one case, but in the remainder it was detectable within mucous epithelia in minimal amounts and in an atypical granular distribution; (b) nonsecretors (n = 3) reversely exhibited complete negativity for Leb but a minimal staining for Lea. These findings are in harmony with the well established Lewis serology typing of secretions in Lewis negative individuals. Thus, a minimal Lewis antigen biosynthesis and secretion seem to occur in the absence of the Le gene: A alpha-4-L-fucosyltransferase of low activity might be the product of the allele le.     

Light-microscopic examination of ABH and Lewis antigens in human tracheal and epiglottic glands using the avidin-biotin-peroxidase complex technique

The localization of ABH and Lewis antigens was examined in formalin-fixed, paraffin-embedded human tracheal and epiglottic glands using monoclonal anti A, B, H, Lea and Leb antibodies. The mucous cells of the glands showed reactivity with antibodies corresponding to the respective ABO blood groups of the tissue donors. The mucous cells from one blood group A, Le(a-b-) individual showed no reactivity with any antibodies and those from another blood group A, Le(a-b-) individual showed reactivity only with anti A antibody. In individuals from blood group Le(a + b-) of all ABO groups, the mucous cells reacted exclusively with anti Lea. In blood group O, Le(a-b+) individuals, the mucous cells showed intense reaction with anti H and Leb antibodies and weak to moderate reactivity with anti Lea. In Le(a-b+) individuals of A1, B and A1B blood groups, the mucous cells showed strong reactivity with anti A and/or B antibodies, moderate with anti Leb, weak or no activity with anti Lea and absent with anti H. In blood group A2 Le(a-b+) individuals, the mucous cells stained with anti A were weakly stained or completely unstained with anti H antibody, but cells negative with anti A gave strong positive reactions with anti H antibody.     

Detection of cocaine metabolite in perspiration stain, menstrual bloodstain, and hair

Low nanogram and picogram quantities of cocaine metabolite equivalents were detected in extracts from perspiration stains, menstrual bloodstains, and hair using radioimmunoassay. The theory of drug inclusion in hair and its significance are discussed.     

The use of immunoenzyme analysis for determining ABH antigens in traces of saliva and sperm]

The authors suggest a simple sensitive technique for enzyme immunoassay (EIA) of ABH antigens in saliva and semen. A two-staged dot blot solid-phase EIA on nitrocellulose membranes was employed with anti-ABH monoclonal antibodies obtained in immunization of mice with human red cells. 4-chloro-1-naphthol substrate solution was used to visualize the peroxidase label. The results of analysis of salivary and spermatic samples obtained from donors of various groups evidence that this EIA variant may be useful in forensic medicine.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography-mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F(254) plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm x 150 mm, 5 microm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.     

Simultaneous identification/determination system for phentolamine and sildenafil as adulterants in soft drinks advertising roborant nutrition

An easily available, simultaneous identification/determination procedure for phentolamine (PHE) and sildenafil (SIL) in adulterated dietary supplements was established by using a combination of three different analytical methods; thin-layer chromatography (TLC), liquid chromatography–mass spectrometry (LC/MS) and a high-performance liquid chromatography (HPLC)/photo-diode-array. The sample solution for TLC was applied to silica gel 60 F₂₅₄ plates with chloroform/ammonia solution (28)/methanol (70:5:3, lower layer) and chloroform/diethylamine/methanol (15:3:2) as the developing solvent. Spots were located under UV radiation at 254 nm. Mass spectra of PHE and SIL by LC/MS were investigated with electrospray ionization (ESI) interface, under both positive and negative ion mode. The HPLC analysis was performed on a column of Wakosil 5C18 (4.6 mm×150 mm, 5 μm) with water/methanol/acetonitrile/triethylamine (580:250:170:1) adjusted with phosphoric acid to pH 3.0 as the mobile phase, and the effluent was monitored with a photo-diode-array detector. Quantitative HPLC analysis of PHE and SIL were detected at 280 nm. When this procedure was applied to commercial soft drinks, PHE and SIL were identified and determined at a concentration of 17 mg PHE and 44 mg SIL per bottle, respectively. The procedure described here is available for the screening of PHE and SIL in adulterated supplements.     

GC—MS同时测定血液中苯海索、氯丙嗪和氯氮平

目的建立GC—MS同时测定血液中苯海索、氯丙嗪和氯氮平的方法。方法血液中加入内标SKFszs。．在pH〉10条件下用V（苯）：v（乙酸乙酯）=1：l提取,用GC—MS全扫描法进行定性检测：以地西泮一d;为内标,样品在pH〉10条件下用V（苯）：v（乙酸乙酯）=l：1提取,用GC—MS选择离子监测方法进行定量检测．结果苯海索、氯丙嗪和氯氮平在20～10000ng／mL范围内呈线性关系,最小检测限分别为0．3、0．3和0．7n幽L（信噪比≥3）,方法回收率为79．9％～85．5％,日内、日间精密度均小于5．1％。结论本方法可同时分析血液中苯海索、氯丙嗪和氯氮平,方法灵敏度高、快速、操作简便,适用于苯海索、氯丙嗪和氯氮平的血药浓度监测和急性中喜案件竹枪测     

用双色荧光原位杂交技术鉴定血痕性别

目的 探讨荧光原位杂交技术在血痕性别鉴定中应用及其价值。方法对20例新鲜人血及20例1-2年人血痕的X、Y染色体采用双色荧光探针进行原位杂交分析。结果 人新鲜血,男性X、Y信号检出的完整率为98.8％,其中Y信号的检出率为100％,女性X、X信号检出的完整率为96.5％;1-2年人血痕,男性X、Y信号检出的完整率为88％,其中Y信号的检出率为90％,女性X、X信号检出的完整率为80％;40例血液(痕)性别检测的符合率为100％。结论双色荧光原位杂交技术可以鉴定血痕性别。     

同频音掩蔽试验及其在法医学鉴定中应用的研究

目的应用同频音掩蔽试验观察不同个体最小对侧掩蔽级(MCML)与主观纯音听阈之间的关系,进而通过MCML判定被试者主观真实听阈。方法30例受试者(60耳)分别进行纯音测听,首先测出双耳的纯音听阈,然后应用同频音掩蔽试验测试各个频率的MCML。结果当被掩蔽耳的声强处于阈值时,掩蔽耳的MCML与主观纯音听阈差值在0～30dBHL之间,其中差值在10dBHL以内的占82.4%,在15dBHL以内的占97.1%;当被掩蔽耳的声强处于阈上10dBHL时,掩蔽耳的MCML与主观听阈间差值在0～35dBHL之间,其中差值在25dBHL以内的占90.5%,在30dBHL以内的占98.1%。结论利用同频音掩蔽试验可以准确地判定各个频率被掩蔽耳的真实主观听阈。特别是对于语音范围内听力状况的法医学评定更具有特殊的意义。     

动脉喷溅血迹动力学及形态学的模拟实验观察

目的观察不同压力、管径对在水平方向上形成的喷溅状血迹的喷射距离及形态的影响。方法建立室内现场环境,利用自制的模拟喷射装置,在60～210mmHg范围内设6种压力,在1.5～4.5mm范围内设4种管径条件,于50、100、150cm 3种高度,制作动脉喷溅血迹。观察水平面上不同喷射高度的喷溅血迹的分布范围、血迹大小及形态特征,并测量其距离,采用SPSS 13.0统计软件进分析,并进行方差检验。结果在不同高度,血液喷射距离随压力增大而增加,随管径增大而减小,两因素间存在交互作用,距离与压力及管径存在较好的线性关系,可得出回归方程。而喷溅血迹的形态特征总体趋势为:高度越高圆形血滴直径约大;管径越粗,边缘毛刺状突起越明显;压力越大,喷射距离越远,且卫星状血迹逐渐增多,拖尾更拉长;随管径的增加,出现椭圆形血滴所需的压力越高。结论动脉喷溅血迹的形态及喷射距离的观察与测量,可用于推断命案现场喷溅源位置及人体受损伤时的体位。     

气相色谱法同时测定血清中甲醇、乙醇、正丙醇

目的建立气相色谱同时测定血清中甲醇、乙醇、正丙醇含量的方法。方法改变气相色谱条件,以异戊醇为内标,采用气相色谱一氢火焰离子化检测器对血清直接进行检测。并通过待测组分与内标物的响应值比进行定量。结果GC／FID法检测血清中的甲醇、乙醇、正丙醇含量,得到了良好的线性关系。乙醇浓度从1～100mg／100ml。的线性关系式为Y=0．4145X＋0．0232（R2=0．9974）、浓度从100～1000mg／100mL的线性关系式为Y=0．4511X＋0．0746（R2=0．9911）,甲醇浓度从l-200mg／100mL的线性关系式为Y=0．2778X＋0．0493（R2=0．9983）。结论该方法操作简便快速,重现性好,通过检测正丙醇还可以推断腐败血样自身产生的乙醇量,是一种较为理想的血醇检测方法。