Development of Rapid and Economical Colorimetric Screening Method for p‐Phenylenediamine in Variety of Biological Matrices and its Application to Eleven Fatal Cases of p‐Phenylenediamine Poisoning

A rapid colorimetric method for detection of p‐phenylenediamine (PPD) in various biological samples is developed. The o‐cresol test for acetaminophen detection has been modified to detect PPD in blood, urine, gastric contents, and liver. After precipitating protein with trichloroacetic acid solution (2 mL, 10% w/v), biological specimens were required to convert PPD metabolites to PPD by acid hydrolysis. Finally, o‐cresol solution (1 mL, 1% w/v), hydrogen peroxide (200 μL, 3%v/v), and concentrated ammonium hydroxide (0.5 mL) were added in the biological samples. The presence of PPD was indicated by formation of violet color which was turned to bluish green color within 10–15 min. The limit of detection was found to be 2 mg/L in blood, urine, and gastric contents and 2 mg/Kg in liver. This method is also free from any potential interference by p‐aminophenol, acetaminophen, and other amine drugs under test conditions. This method was successfully employed to thirteen fatal cases of PPD poisoning.     

开发高灵敏度血痕发光试剂用于法医现场检测

目的开发高灵敏度血痕发光试剂用于法医现场检测。方法本项目通过借鉴ECL发光的原理,通过化学电子链的乒乓共轭激活原理,使用均匀设计实验方法优化条件,合成多个新化合物,开发出新型高灵敏度血痕发光试剂。结果本项目开发的高灵敏度血痕发光试剂灵敏度高,发光时间长,在血液稀释1000倍的情况下,使用Chemi Scope3300化学发光成像系统读取荧光值,经过灰度转化最高值达到56,发光时间达到10分钟。结论本项目成功开发了高灵敏度血痕发光试剂,可以应用于法医现场检测。     

二代测序技术在法医遗传学中的应用研究进展(2011～2016)

对生物检材进行DNA分型是解决法医遗传学实践中个体识别和亲权鉴定问题的重要步骤,法医学实践中复杂生物检材和复杂亲缘关系鉴定等一直是现有的检测分析技术的难点和挑战。随着DNA技术的发展,新的检测分析技术不断引入到法医遗传学领域,以期提高检测效能。二代测序技术具有测序通量高、成本低等特点,能够获得样本DNA详细序列和相对含量等信息,有助于生物检材的检测和案件的分析。二代测序技术在法医遗传学领域的应用受到广泛关注,相关的应用研究逐渐增多。本文就目前法医遗传学领域借助二代测序技术对遗传标记分析的研究进展进行总结,希望能为相关研究和应用提供参考。     

Biological protective factors of criminal offending: implications for risk assessment research and practice

Despite the recognition of the practical and theoretical contributions of protective factors in risk assessment practice, the field has granted significant attention to psychosocial protective factors to the apparent neglect of biological protective factors. This review found a wealth of evidence which strongly and convincingly indicates that biological factors such as high intelligent quotient, executive functioning, skin conductance, and resting heart rate offer protection against criminal and antisocial behaviors. More importantly, the literature is supportive of the view that both risk and protective factors co-occur in the same variables, thus questioning the practice of classifying a set of variables as strictly risk or protective. Specifically, the risk–protective effect is contingent upon individual’s rating as high or low on the factor in question. It is recommended that researchers, academicians, and practitioners strive in their efforts to canvass other salient factors beyond the psychosocial factors as these factors can significantly and positively impact the risk assessment field, both theoretically and practically.     

海南汉族人群19个STR基因座遗传多态性及其应用

目的建立海南地区汉族人群19个常染色体STR基因座的遗传多态性数据资料,并探讨此19-STR基因座系统在亲子鉴定中的应用。方法对海南汉族462例无血缘关系个体,采用Goldeneye~(TM) 20A系统复合扩增并检测,得到19个STR基因座的遗传数据信息;在283例亲子鉴定案例中,评价19-STR基因座系统的应用。结果 19个STR基因座的基因频率分布均符合Hardy-Weinberg平衡(P0.05),杂合度在0.603~0.914之间,累积个体识别率大于0.999 999 999 999 999,累积三联体非父排除率为0.999 999 994。283例亲子鉴定中,三联体170例,二联体113例;认定案例247例(87.3%),排除案例36例(12.7%);发生等位基因突变案例14例(4.9%),均为一步突变。结论 19个STR基因座中的14个基因座具有高度遗传多态性,19-STR基因座复合扩增分型系统具有较高的非父排除效能,可满足海南地区亲子鉴定的需要,同时应注意亲子鉴定中的基因突变现象。     

磁珠直接吸附法对体态检材游离DNA的提取

目的采用磁珠直接吸附法对人体尿液、唾液、血液3种体态生物检材中的游离DNA进行提取检验,为法医物证中游离DNA的研究及检验工作提供参考。方法对3种生物检材采取离心吸取上清液的方法分离游离DNA,然后采用磁珠直接吸附法进行提取纯化,Identifiler-Plus试剂盒进行复合扩增后常规STR检测。结果在3种检材中均检出了游离DNA,其中血液中游离DNA检出率为100%,唾液为90%,尿液为70%。结论人体体态生物检材中存在游离DNA,同时磁珠直接吸附法可高效、快捷的提取生物检材中的游离DNA。     

STR基因座单倍型的推断方法初探

本文参考Browning SR等提出的以SNP等位基因频率为基础,通过统计学模型推断SNP单倍型的方法,初步探讨亲权鉴定中STR基因座单倍型的推断方法。以两个处于连锁不平衡状态的X-STR基因座的女性分型结果为例进行说明。本方法为STR单倍型的推断提供了一个思路,有助于更科学准确地进行STR分型结果的解释。     

STR遗传多态性调查中样本量和采样方式选择初探

目的对STR基因座进行遗传学调查时样本量大小和采样方式进行考察分析。方法用DNA Typer~(TM)19试剂盒对血卡样本进行直扩,ABI3730型遗传分析仪电泳检测,Genemapper ID v3.2软件进行等位基因分型,根据公式计算群体遗传学参数。计算样本量在50、100、150、200、250、300、350、400、450、500十个水平上遗传多态性水平,并评估与总体的差异。计算常见的四种采样方法(整群采样、随机采样、系统采样、分层采样)所抽取样本遗传多态性水平,并评估抽样误差。结果 18个STR基因座在河北地区16 058份随机样本共检出317种等位基因,基因频率分布在3.114e-5~0.515。18个STR基因座在河北群体水平上PM为6.04e-14,TDP为0.999 999 999 999 94,CEP为0.999 999 987 514 828。PM值、CEP值在样本量大于200后中值基本稳定。四种抽样方法的抽样误差大小是:整群抽样≥单纯随机抽样≥系统抽样≥分层抽样。结论 DNATyper~(TM)19试剂盒的18个STR基因座在河北地区具有较高的遗传多态性水平。在小范围内进行人群频率调查时,可随机选择200份样本代表当地遗传多态性水平。在相对较大范围或遗传背景复杂的区域,可采用分层抽样的方法降低抽样误差。     

河南汉族群体20个常用STR基因座突变分析

目的观察20个常染色体STR基因座突变在河南汉族人群中的分布情况。方法从3011例确认亲子关系的亲子鉴定案例中筛查基因突变事件,确定突变来源,统计各STR基因座的突变率,分析突变规律并与部分不同地区的人群STR基因座突变情况进行比较分析。结果在20个STR基因座中观察到19个基因座的发生的76次突变事件,平均突变率为0.08%累计突变率达到1.662 9%;父、母源性突变的比率大致为8:1;河南汉族人群在Penta E和D12S391基因座突变率明显低于北方汉族人群(P0.05);在D6S1043、CSF1PO和D12S391基因座突变率明显低于广东人群(P0.05);在CSF1PO基因座突变率明显低于云南汉族人群(P0.05)。结论 STR基因座突变现象较为常见,不同基因座的突变率存在着明显的地区差异。     

Parents’ knowledge and attitudes about youths’ interrogation rights

Some states and police agencies require youth to consult with parents before or during interrogation by police, yet these policies rely on the untested assumption that parents themselves are knowledgeable about police interrogation practices and youths’ rights. This study assessed knowledge of, and attitudes about, juvenile interrogations in a sample of parents (N?=?294) recruited from urban locales. On average, parents correctly answered fewer than half of the questions about juvenile interrogation practices; knowledge about parental notification procedures was especially poor. At the same time, parents strongly endorsed youths’ rights to support (including support from parents) during police questioning contexts and only moderately endorsed youths’ decision-making autonomy, even for older youth who are legally adults.