Results of the 2003-2004 GEP-ISFG collaborative study on mitochondrial DNA: focus on the mtDNA profile of a mixed semen-saliva stain

We report here a review of the seventh mitochondrial DNA (mtDNA) exercise undertaken by the Spanish and Portuguese working group (GEP) of the International Society for Forensic Genetics (ISFG) corresponding to the period 2003-2004. Five reference bloodstains from five donors (M1-M5), a mixed stain of saliva and semen (M6), and a hair sample (M7) were submitted to each participating laboratory for nuclear DNA (nDNA; autosomal STR and Y-STR) and mtDNA analysis. Laboratories were asked to investigate the contributors of samples M6 and M7 among the reference donors (M1-M5). A total of 34 laboratories reported total or partial mtDNA sequence data from both, the reference bloodstains (M1-M5) and the hair sample (M7) concluding a match between mtDNA profiles of M5 and M7. Autosomal STR and Y-STR profiling was the preferred strategy to investigate the contributors of the semen/saliva mixture (M6). Nuclear DNA profiles were consistent with a mixture of saliva from the donor (female) of M4 and semen from donor M5, being the semen (XY) profile the dominant component of the mixture. Strikingly, and in contradiction to the nuclear DNA analysis, mtDNA sequencing results yield a more simple result: only the saliva contribution (M4) was detected, either after preferential lysis or after complete DNA digestion. Some labs provided with several explanations for this finding and carried out additional experiments to explain this apparent contradictory result. The results pointed to the existence of different relative amounts of nuclear and mtDNAs in saliva and semen. We conclude that this circumstance could strongly influence the interpretation of the mtDNA evidence in unbalanced mixtures and in consequence lead to false exclusions. During the GEP-ISFG annual conference a validation study was planned to progress in the interpretation of mtDNA from different mixtures.     

Homicide by decubitus ulcers

Traditionally, the only penalties for poor treatment of nursing home patients have been civil lawsuits against nursing homes and their employees by families, or fines and license suspension by government organizations. Recently, government agencies have become much more aggressive in citing institutions for the development of decubitus ulcers (pressure sores) in their patients. A few government institutions have concluded that in some cases, the development of ulcers with resultant death is so grievous that there should be criminal prosecution of the individuals and/or institutions providing care. A leader in this concept has been the State of Hawaii. In November 2000, the State of Hawaii convicted an individual of manslaughter in the death of a patient at an adult residential care home (a form of nursing home) for permitting the progression of decubitus ulcers without seeking medical help, and for not bringing the patient back to a physician for treatment of the ulcers.     

儿童及青少年组损伤特点分析

儿童及青少年遭受意外事件和暴力事伤害的现象日益突出，本文对１５６例２～１７岁涉及诉讼的未成年人法医学鉴定案例进行回顾性研究，结果表明：３月、４月、８月、１２月四个月发案率偏高，每天下午４点前后最易发生伤害案件；损伤部位以头面部最多见，损伤类型以软组织损伤最多；案发地点于儿童组以住家及其周围场所、学校或幼儿园居多，于青少年则以公共场所居多；加害人多为熟人，包括同学、邻居，青少年受陌生人攻击明显增多，儿童遭受意外事件多，受故意伤害的少，青少年组则刚好相反。同时，作者讨论时还指出，我国目前存在虐待儿童和忽视儿童的现象，以后者更为普遍，这种消极不作为的侵害未成年人权益的现象在司法实践中应引起重视。     

Neuropathological findings associated with retained lead shot pellets in a man surviving two months after a suicide attempt

We describe the neuropathological findings in a 30-year-old man who died two months after attempting suicide with a shotgun. We focused our study on lesions associated with retained lead shot pellets and distant therefrom, as well as lesions distant from the principal site of injury. At the sites of the retained lead shot pellets, we found macrophage proliferation and astrocyte activation, together with axonal spheroids and signs of neuronal damage. In the remaining white matter we observed axonal swellings, astrocyte activation and rarefaction of the neuropil; regressive phenomena of the neurons were also present. All axonal spheroids immunoreacted with antibodies against APP, alphaB-crystallin, NF subunits and ubiquitin. Most reactive astrocytes were positive for GFAP and alphaB-crystallin immunostaining. Some neurons immunoreacting with alphaB-crystallin were also found. These data indicated that an important local reaction developed at the sites of lead shot retention, and mild signs of diffuse axonal damage were found throughout the brain.     

制约核扩散的国际法机制

1968年7月签署的《不扩散核武器条约》中规定了有权拥有核武器的国家只能是联合国五个常任理事国,其他国家都是"无核国家",有义务不发展、不制造核武器。但是到2005年底,世界上已有八、九个国家拥有核武器,大约27000枚核弹头,这样多的核武器足以使地球毁灭若干次。制止核扩散、维护国际安全成为当今国际社会关注的焦点问题。目前,制约核扩散的国际法机制主要以《不扩散核武器条约》(NPT)和国际原子能机构(IAEA)为核心。围绕着这两个核心还存在着一些其他的条约和机构。但是,这个国际法机制并不完善,存在很多问题。     

“亚裔美国人”概念的起源及其含义的变迁

亚裔美国人是美国多种族社会中正在崛起的一支族裔集团,它在美国社会生活的各个方面日益显示出其强大的潜力,亚裔美国人这个概念的形式得益于1960年代末的亚裔美国人运动,它既是亚裔集团泛亚的归属意识的要求,也是美国联邦统计体系的规定,并且因着不同的历史条件其含义也随之发生变化;从自定义的美国人到精选出的“模范少数民族”再到种族类别的亚裔美国人和朝向多种族／族裔类别发展。