HPLC法检测人外周血5-~mC含量及其与年龄相关性研究

目的探讨人外周血中5-mC含量随年龄变化的规律。方法94例健康个体(4~87岁,男性50例,女性44例)按年龄分为6组<20岁、20~30岁、30~40岁、40~50岁、50~60岁及>60岁组,用HPLC法对外周血中5种脱氧核苷进行定量分析。结果50~60岁组(平均年龄54.7岁)和>60岁组(平均年龄71.7岁)间的5-mC含量差异无显著性,但与其它4组有明显差异(P<0.0001);<20岁、20~30岁、30~40岁和40~50岁4组间无显著性差异。男性5-mC含量的均值(3.5%±0.005%)稍低于女性(3.32%±0.006%),但差异无统计学意义。结论5-mC的含量随着年龄的增长呈下降趋势,但其下降程度很小。     

人牙咬痕形态学变化动态过程研究

目的　研究人牙咬痕形态学变化的动态过程 ,了解咬痕发生、发展的变化规律 ,为已发生变化的咬痕同一认定提供依据。方法　动态追踪观察活体及死亡动物咬痕的变化过程 ,并测定其相关形态参数 ,多元逐步回归分析咬痕形态、牙面积、时间、牙合力、牙宽度、牙厚度之间的关系 ,建立咬痕形态学变化回归方程。结果　咬痕的形态、牙形态、时间、牙合力有一定的数学关系 :S =-6 96-1 68× 10 2 T -0 11F +2 2 1W +3 75H (活体狗实验T <3 60min) ;S =-2 1 90 +5 3 4× 10 2 T -0 3 6F +4 5 7W +6 66H (死亡狗实验T <14 40min)。     

Drugs and alcohol in hypothermia and hyperthermia related deaths: a retrospective study

Hypothermia and hyperthermia related cases recorded for the period 1973 to 1984 were collected from the files of the Department of Forensic Medicine, University of Oulu, and the necropsy protocols including toxicological results were analyzed. The fact that similar alcohol concentrations were found in both types of fatalities points to the poikilothermic effect of alcohol in humans, as found in animal studies. Both types of deaths seem to be associated with the alcohol elimination phase. Antidepressants and neuroleptics were most often found in the hypothermia cases, but benzodiazepines were also quite frequently present. In spite of the diminished use of barbiturates, these still appear in hypothermia fatalities. Certain other drugs that affect thermoregulation were also noted in solitary cases. Extended toxicological analysis was seldom made in the cases of hyperthermia deaths, and no firm conclusions on the poikilothermic effect of psychotropic drugs could be reached, for example. Therapeutic drug concentrations did not alone predispose the subjects to hypothermia, but appeared in connection with alcohol consumption or chronic diseases.     

Age assessment by magnetic resonance imaging of the knee: a preliminary study

The authors developed an original magnetic resonance imaging (MRI) staging system for epiphyseal fusion of growth plate maturation of the knee and evaluated its reliability and validity for age assessment of living individuals. A total of 290 MRI scans of the knee were reviewed retrospectively in patients aged from 10 to 30 years old (138 males, 152 females). Five original MRI stages were defined to assess the degree of maturation of the distal femoral and proximal tibial epiphyses. Intra-observer variability was excellent and inter-observer variability was good, demonstrating the reliability and the validity of this original MRI staging system. In both sexes, the changes of growth plates (proximal tibial or distal femoral) were associated with age (p<0.001). Our results agreed with classic data on skeletal maturation of the knee, with globally earlier maturation in females than in males, and also earlier maturation of the proximal tibial epiphysis than of the distal femoral epiphysis. MRI of the knee is an efficient non-invasive method of age assessment, without the disadvantage of X-ray exposure. Further studies with larger groups are needed to support our results.     

Age estimation from the human os coxa: a test on a documented Italian collection*

Current standards for age at death estimation from the pelvis are based on Americans of European and African ancestry. Our limited understanding of population variability hampers our efforts to apply these techniques to the various skeletal populations around the world, especially in global forensic contexts. However, documented skeletal samples are rare, limiting our ability to test our techniques. This study tested the Suchey-Brooks pubic symphysis aging method and the auricular surface method originally developed by Lovejoy et al. on a large sample (n = 404) of known sex and age from the Sassari Collection, housed at the Museum of Anthropology at the University of Bologna, Italy. The results indicate that for both methods, bias and inaccuracy increased with age and actual age tended to be underestimated over the age of 40. The auricular surface method performed slightly better, exhibiting slightly lower levels of bias and inaccuracy, especially for males.     

Fatal air embolism in diving. A morphologic study

Two cases of barotrauma as a result of excess pulmonary pressure with subsequent air embolism are reported. Both cases involved serious diving safety errors. The morphology of this type of barotrauma is described, with particular reference to the etiology of the phenomena involved. Some specific points regarding the autopsy procedure in connection with such diving accidents are discussed.     

人外周血FoxO3a mRNA表达随龄变化规律的初步研究

目的评估人外周血中FoxO3a mRNA表达的随龄变化规律,为法医学个体年龄推断寻找新的分子指标。方法采集80个健康无关个体血样,按年龄分为8组:≤9岁、10～19岁、20～29岁、30～39岁、40～49岁、50～59岁、60～69岁、≥70岁组,每组10人。提取总RNA后,用实时定量RT-PCR技术检测FoxO3a mRNA的表达水平。结果人外周血FoxO3a mRNA表达随年龄的增长而逐渐增加,具有良好的相关性(r=0.841,P0.01),以年龄分组为自变量,FoxO3a mRNA表达水平为因变量,可得拟合曲线Y=0.001e0.418x。结论人外周血中FoxO3a mRNA表达具有较强的年龄特征,有望成为年龄推断的有用指标之一。     

Forensic medical estimation of acute blood loss based on morphologic and functional changes in the internal organs

The objective of the present work was to obtain histological and morphometric characteristics of internal organs available for forensic medical examination from 236 corpses of subjects aged between 23 to 48 years whose death was caused by acute blood loss following a mechanical injury and concomitant alcohol or drug intoxication. Diagnostic signs of acute blood loss have been identified that can be used by forensic medical experts to estimate the length of the terminal period and reveal characteristic features of blood loss associated with alcohol and drug intoxication.     

Exploring sexual harassment and related attitudes in Beninese high schools: a field study

Sexual harassment severely impacts the educational system in the West African country Benin and the progress of women in this society that is characterized by great gender inequality. Knowledge of the belief systems rooting in the sociocultural context is crucial to the understanding of sexual harassment. However, no study has yet investigated how sexual harassment is related to fundamental beliefs in Benin or West African countries. We conducted a field study on 265 female and male students from several high schools in Benin to investigate the link between sexual harassment and measures of ambivalent sexism, gender identity, and rape myth acceptance. Almost half of the sample reported having experienced sexual harassment personally or among peers. Levels of sexism and rape myth acceptance were very high compared to other studies. These attitudes appeared to converge in a sexist belief system that was linked to personal experiences, the perceived probability of experiencing and fear of sexual harassment. Results suggest that sexual harassment is a societal problem and that interventions need to address fundamental attitudes held in societies low in gender equality.     

人脑挫伤后GFAP,PCNA的法医病理学研究

采用在实际工作中所遇到的脑挫伤案例标本 ,利用免疫组织化学染色 ,观察人脑挫伤后GFAP ,PCNA的改变 ,用图象分析仪对免疫组织化学染色阳性细胞的面积和灰度等进行定量测量 ,EpiInfo统计软件分析 ,得出人脑挫伤后GFAP ,PCNA变化的时间性规律 ,为脑挫伤形成时间推断 ,提供新的形态学依据。GFAP阳性细胞面积、灰度伤后24h即有显著增加 (P<0 01) ,7天达高峰 (P<0 01) ,以后有逐渐下降的趋势 ;PCNA阳性细胞面积、灰度于伤后4天达到最大值 (P<0 01) ,以后逐渐下降。因此 ,伤后人脑组织GFAP、PCNA免疫组织化学染色阳性细胞面积、灰度改变有时间规律 ,GFAP、PCNA可作为2天到20天间不同时间脑损伤的推断指标。     

Taphonomic changes to blunt force trauma: a preliminary study

This study examines the effects of taphonomic processes on blunt force trauma (BFT) through an experimental study involving pig heads. Of particular concern is the possibility that taphonomic changes can create pseudo-trauma and/or conceal evidence of actual trauma. BFT was inflicted on 10 pig skulls using a hammer. The skulls were subsequently exposed to the environment for 12 months. Seven taphonomic changes were evaluated: the freeze-thaw cycle; rodent gnawing; carnivore scavenging; presence/weight of soil; presence/weight of rain and snow; movement/displacement of bones; and discoloration due to sun bleaching and grass staining. Taphonomic effects varied between cancellous, compact, fresh, and degreased bone. Freezing and thawing, exposure to rain and snow, movement of the skulls, and soil erosion altered and, in some cases disguised, pre-existing trauma. Rodent and carnivore activity did not obliterate evidence of BFT. Recommendations for evaluating BFT on remains affected by taphonomic processes are presented. As each taphonomic process outlined by this study has the potential to disguise antemortem injury, the authors propose that one must carefully examine large, circular openings in the skull that may represent the remnant evidence of BFT.     

从法医相关性昆虫体内提取人类DNA的研究进展

本文从嗜血性昆虫、嗜尸性昆虫、嗜骨性昆虫及实验技术等多角度阐述了从法医相关性昆虫嗉囔中提取人类DNA的可行性及国际研究和应用进展。     

从法医相关性昆虫体内提取人类DNA的研究进展

本文从嗜血性昆虫、嗜尸性昆虫、嗜骨性昆虫及实验技术等多角度阐述了从法医相关性昆虫嗉囔中提取人类DNA的可行性及国际研究和应用进展。     

人体皮肤创伤组织细胞因子表达的时间相关性

目的探讨TGF-β1、b—FGF和VEGF在人体皮肤创伤组织中的表达变化及其与损伤时间的关系。方法收集15例机械性致伤的人体皮肤组织(受伤5—120min内死亡),常规制作组织切片后进行免疫组化染色,并统计分析TGF-β1、b—FGF和VEGF因子的表达情况。结果 TGF-β1在16—50min组表达升高,60～120min组呈阳性至强阳性表达;b—FGF在16—50min组表达升高明显,强阳性表达亦出现在60～120min组;VEGF仅在60—120min组出现阳性表达。统计学分析表明,TGF—β1和b—FGF的表达升高分别在受伤60~120min(P<0.01)和在16—50min(P<0.01)有显著性意义,VEGF表达升高只在60~120min(P<0.05)有显著性意义。结论 TGF-β1、b—FGF和VEGF的表达时间和表达强度与损伤时间有关;TGF-β1、b—FGF和VEGF的表达可为人体短存活期损伤时间的推断提供参考。     

人体死后肝细胞DNA含量与死亡时间关系的研究

目的研究人体死后肝脏细胞DNA含量变化与死亡时间的关系及影响因素。方法选取46例已知死亡时间的人体肝脏,根据离体肝脏所处的环境温度分为12—19％（A组）和20—27％（B组）两组,每组23例。在死后24～72h内每隔4h穿刺取肝组织1次,制成细胞悬液,经RNA酶消化,PI染色后,用流式细胞仪测定被检测细胞中含不完整DNA的细胞数所占百分比,所得数据经Exp032V1．2软件计算N值。结果死后24～72h肝细胞N平均值,A组从10．91％增至49．72％,B组从16．22％增至69．63％。两组N平均值随死亡时间的延长均逐渐增高,与死亡时间有相关性,A组r值为：0．598,B组r值为0．77357。并且建立了不同环境温度对应的回归方程。结论在不同环境温度下,死后24～72h内人体肝脏细胞DNA降解均随死亡时间的延长和环境温度的升高而逐渐加快,相关数据可望为死亡时间推断提供一定参考依据。     

Age estimation using carpals: study of a Slovenian sample to test Cameriere's method

Carpals are often used as age indicators. In a recent study, Cameriere et al. studied the use of the ratio between the total area of carpal bones and epiphyses of the ulna and radius (Bo) and carpals (Ca) as age indicators. The present study, of a sample of 158 Slovenian children and adolescents aged between 6 and 16 years, focused on analysing the best regression for age estimation. The regression model yielded the following equation: age=-3.411+0.942 g+20.927(Bo/Ca), and explained 91.6% of total variance (R(2)=0.916). The median of the absolute values of residuals (observed age minus predicted age) was 0.09 years, with a quartile deviation of 0.786 years, and a standard error of estimate of 0.658 years. Comparisons between the previous equation referring to Slovenian children and the equivalent linear equation proposed by Cameriere et al. did not reveal any significant differences between the intercepts and slopes of the two linear models. These results suggested a common regression model for both Italian and Slovenian samples. The common regression model, describing age as a linear function of gender and Bo/Ca ratio, yielded the following linear regression formula: age=-2.907+0.408 g+20.757(Bo/Ca). This model explained 86% of total variance (R(2)=0.86). The median of the absolute values of residuals (observed age minus predicted age) was 0.02 years, with a quartile deviation of 1.02 years and a standard error of estimate of 0.96 years.     

Age calculation using X-ray microfocus computed tomographical scanning of teeth: a pilot study

To correlate dental age with an individual's chronological age based on the calculated volume ratio of pulp versus tooth volume measured, an X-ray microfocus computed tomography unit (microCT) with 25 microm spatial resolution was used to non-destructively scan 43 extracted single root teeth of 25 individuals with well-known chronological age. Custom-made analysis software was used by two examiners to obtain numerical values for pulpal and tooth volume. The ratio of both was calculated and statistically processed. No significant intra- or inter-examiner differences were found. In fact, a very strong concordance correlation coefficient was found. Linear regression analysis showed a coefficient of determination (r) of 0.31 which suggests that there is a rather weak correlation between the volume ratio of pulp versus tooth and biological age. Although rather time consuming, this technique shows promising results for dental age estimation in a non-destructive manner using X-ray microfocus computed tomography.