用α-珠旦白-3’HVR探针研究DNA指纹

用α-珠蛋白-3’HVR探针,经Southern印迹法,对100名不相关个体及4个家系的32名相关个体的DNA指纹进行了检测,所产生的DNA图谱具有高度的个体特异性,在被测的所有个体中无一相同。经统计学计算表明,任意两个个体DNA指纹图重合率为10~(-11)。家系分析毒明,DNA片段严格按照孟德尔方式遗传。该探针的应用,将在法医学亲子鉴定和个人同一认定中发挥重要的作用。     

A high selective screening test for methamphetamine in human urine

A high selective screening test (Ad-Tip method) for methamphetamine in human urine has been devised. The method involves a brief extraction from a urine sample with an Ad-Tip (ODS-silica minicolumn), washing, eluting with modified Simon's reagent, and coloration with carbonate buffer. Detection limit of methamphetamine in urine is 1 microgram/ml and the test takes within 3 min/sample. The results of the Ad-Tip method were almost identical to those of laboratory analyses.     

番鸭呼肠孤病毒乳胶凝集试验检测方法的建立

建立了用纯化的抗番鸭呼肠孤病毒(DRV)抗体致敏乳胶检测DRV抗原的方法。通过试验,确定抗体致敏乳胶的最佳浓度为1∶10(IgG蛋白浓度为0.424 2 mg/mL),最佳致敏温度为37℃,最佳致敏时间为120 min。用所建立的方法对人工感染的1 日龄雏番鸭30 只进行粪便检测,结果表明,感染后第3 d粪便中即可检测到病毒,直至人工感染鸭全部死亡都可从粪便中检出病毒抗原;对同样人工感染的30只1日龄雏番鸭的心、肝、脾病料用所建立的方法检测,结果表明,感染后第4 d,2/3番鸭脾病料检出阳性;感染后第5 d,2 只死亡鸭中有1 只肝病料检出阳性,脾病料2只都呈阳性;此后的病死鸭脾和肝病料均为阳性,而心则未检出阳性。     

单亲案亲权鉴定结果判定策略

目的探讨用STR基因座进行单亲鉴定出现矛盾基因座时下结论的策略。方法根据基因频率和遗传规律,推导单亲案亲权鉴定时的非父排除率。根据平均单亲非父排除率和平均突变率,用二项分布公式分别计算出现不同数目矛盾基因座时真父和假父的概率和似然率(亲权指数)。结果对STR共显性基因座,其单亲非父排除率的计算公式为:PEM=∑i=n1pi2(1-pi)2 ∑i相似文献   

Incestuous paternity detected by STR-typing of chorionic villi isolated from archival formalin-fixed paraffin-embedded abortion material using laser microdissection

Microscopic examination of a blood clot expelled by a physically and mentally disabled woman taken to the emergency room because of genital bleeding revealed the presence of chorionic villi encircled by decidua, hemorrhage, and necrosis. In order to identify the father of the product of conception, sections of formalin-fixed, paraffin-embedded abortion material were subjected to laser microdissection: DNA extraction from chorionic villi selectively isolated from the surrounding tissues allowed successful STR-typing of fetal cells, which was otherwise prevented by excess maternal DNA. The large number of homozygous genotypes in the fetal profile suggested incestuous paternity. Analysis of reference DNA samples from male relatives excluded the woman's father, paternal grandfather, and maternal grandfather, whereas the obligate paternal alleles of the fetus were constantly present in the genotypes of the woman's brother, clearly demonstrating brother-sister incest (probability of paternity > 99.99999%).     

Probability of exclusion in paternity testing: time to reassess

The average exclusion probability is a measure of efficiency in paternity testing; it refers to the a priori ability of a battery of tests to detect paternity inconsistencies. This parameter measures the capacity of the system to detect a false accusation of paternity. Traditionally, this average exclusion probability has been estimated as the probability of excluding a man who is not the father by an inconsistency in at least one of the studied loci. We suggest that this criterion should be corrected, as currently the presumed father is excluded when at least three genetic inconsistencies are found with the child being tested, not just one. This change of criterion has occurred because of the use of microsatellite loci, whose mutation rates are much greater than those of the coding genes used previously in paternity studies. We propose the use of the average probability of exclusion for at least three loci (not only one), as an honest measure of the combined probability of exclusion of several loci, and we propose an algebraic expression to calculate it.     

Alpha-amylase kinetic test in bodily single and mixed stains

Recently, in Italy, a murder and a putative sexual violence was accomplished on a child. A bodily fluids mixture on the child's underwear between the victim (female) and the suspect (male) was ascertained by short tandem repeat (STR) DNA typing and, due to the absence of seminal fluid, saliva from the suspect and urine from the child was hypothesized. In order to investigate the possibility of specifically and rapidly detecting saliva stains both alone and mixed with other bodily fluids, we used a quantitative spectrophotometric technique, named Amylase test, for the detection of alpha-amylases. We determined alpha-amylase activity and reaction kinetic curves in several samples collected from the child's underwear. In order to confirm our intuition, we first tested saliva, perspiration, and urine, singularly and in mixtures; second, several forensic stains including saliva, perspiration, urine stains, saliva/perspiration, and saliva/urine mixture stains were tested. Evaluating alpha-amylase activity values and time-course curves' behavior of alpha-amylase reactions we were able to recognize successfully, in all cases, the presence of saliva and to distinguish it specifically from other bodily fluids containing alpha-amylase. A further confirmation of our result was provided by STR DNA typing on several areas of the underwear: a clear correlation between alpha-amylases activity and male DNA was detected on all the samples evaluated.     

欧美并购控制法实体标准比较研究

实体标准是整个并购控制体系的核心 ,也是反垄断法的重要内容之一。欧盟最新并购控制立法确立的“严重妨碍有效竞争”实体标准与美国奉行的“实质性减少竞争”标准一样都反映着并购控制的本质。欧美采取大同小异的并购实体标准有利于推动国际跨国并购审查结果的一致性 ,促进并购活动的发展。我国应确立“严重妨害正当竞争”实体标准并配套颁布并购评估指南 ,注重并购审查的经济分析     

Identification of human semenogelin in membrane strip test as an alternative method for the detection of semen

Semenogelin (Sg), a protein originating in the seminal vesicles and a substrate for prostate specific antigen (PSA or p30), is a useful marker for the identification of semen. And detection of Sg has been available commercially in a membrane test recently. PSA is commonly used to detect semen in forensic significant samples taken from sexual assault cases. The strip PSA test has been available commercially from various manufacturers for many years. In this study, we evaluated two immunochromatographic membrane tests, one for Sg and the other for PSA by analyzing human semen, other human bodily fluids/materials including urine, blood, saliva, sweat, breast milk, vaginal secretion and fecal materials, semen from various animals and forensic casework samples. The data demonstrate that both Sg and PSA strip tests provide rapid and sensitive method for identification of seminal plasma. These results show that the immunochromatographic method for Sg detection is useful for the identification of seminal plasma in forensic samples, an alternative to the method for PSA detection.     

Discrimination of transparent polyethylene films based on identification of inorganic antiblocking agents

Several nondestructive and semidestructive analyses were used to discriminate colorless transparent polyethylene bags. Transparent plastic bags made from low-density and linear low-density polyethylene usually contain antiblocking agents to prevent sticking of the film, which makes it difficult to open the mouths of plastic bags. Inorganic antiblocking agents are uniformly dispersed in polyethylene films, so they are easily observed using optical microscopy. The particle size distributions of the antiblocking agents were compared by statistical tests. Particle composition was examined by elemental analysis using energy-dispersive X-ray spectrometry with a scanning electron microscope and by molecular vibration analysis using a sensitive microscopic Raman spectrometer. The compositions could be determined nondestructively on the basis of the results. These data reinforce the morphological discrimination. Morphological discrimination of the dispersed antiblocking agent powders, statistical comparison of particle size distributions, and compositional analysis of the antiblocking agents strengthen the ability to discriminate polyethylene films.