Application Value and Research Progress of Human Microbiome in Sexual Assault Cases.

In recent years, sexual assault cases have been on the rise, seriously infringing the legitimate rights and interests of women and children, causing widespread concern in society. DNA evidence has become the key evidence to prove the facts in sexual assault cases, but lack of DNA evidence or only DNA evidence in some sexual assault cases leads to unclear facts and insufficient evidence. With the emergence of high-throughput sequencing technology and the development of bioinformatics and artificial intelligence, new progress has been made in the study of human microbiome. Researchers have begun to use human microbiome for difficult sexual assault cases indentification. This paper reviews the characteristics of human microbiome, and its application value in the inferences of the body fluid stain origin, the sexual assault method, the crime time, etc. In addition, the challenges faced by the application of the human microbiome in practical case handling, the solutions and future development potential are analyzed and prospected.

Sexual behavior differences between amphetamine-type stimulants users and heroin users.

OBJECTIVES: To explore the sexual behavior of amphetamine-type stimulant (ATS) users and heroin users, and to find out the dangerous sexual behaviors, even related risk factors among them. METHODS: Four hundred thirty-eight ATS users and 524 heroin users were recruited in 10 compulsory detoxification treatment centers and voluntary detoxification centers in Beijing, Shenzhen, Guangzhou, Xi'an, and Taiyuan. Their sociodemographic characteristics, history of drug taking, and sexual behaviors were surveyed. RESULTS: Many variables of sociodemographic characteristics and sexual behaviors were significantly different between ATS users and heroin users (P < 0.05). Dangerous sexual behaviors among ATS users include sexual intercourse often or each time after taking drug (30.1%), multiple sexual intercourse (16.5%), casual sex partners (34.0%), homosexual partners (2.5%), and never or occasionally using condom with a steady sex partner (79.3%) or with casual sex partners (39.1%). The rate of ever-infecting sexually transmitted disease (STD) was high in both the groups (ATS, 20.5%; heroin, 30.9%). CONCLUSIONS: Sexual behavior is the main way to transmit STD and human immunodeficiency virus among ATS users. The study results will promote the government's awareness of the issue and take necessary steps to slow the spread of STD and human immunodeficiency virus among the ATS users.

Pattern of drug use and depressive symptoms among amphetamine type stimulants users in Beijing and Guangdong province, China.

BACKGROUND: In recent years, amphetamine-type stimulants (ATS) have increased dramatically in East-south Asia, especially in China. Most ATS users suffered from psychosis comorbidity, and depression is the main syndrome in ATS users. METHODOLOGY: A cross-sectional study of depressive symptoms and associated factors among ATS users was conducted in compulsory and voluntary drug detoxification and rehabilitation centers of Beijing and Guangdong Province from March, 2010 to August, 2010. Total 402 eligible participants were recruited and investigated by trained interviewers using a structured questionnaire, the depression was measured by the short 13-item Beck Depression Inventory (BDI-13). Multiple logistic regression was used to determine the impact of associated risk factors of depressive symptoms (%≥8). PRINCIPLE FINDING: The mean score of BDI-13 is 8.11, and 169 participants (42.04%) have depressive symptoms, including 106 (26.37%) with moderate and 63 (15.67%) with severe depressive symptoms. Higher dose of ATS use, history of ATS relapse were associated with moderate and severe depressive symptoms, the adjusted odds ratios (OR) was 2.62, (95% CI: 1.45-4.74) and 2.01 (95% CI: 1.18-3.42) respectively. The cessation of 12 months or more had less risk of depressive symptoms than the current users, the OR was 0.46 (95% CI: 0.24-0.91), and the ATS users reporting nicotine dependence and alcohol drinking had significantly more risk of depressive symptoms for 3.11 (1.83-5.28) and 2.22 (1.35-3.65) times than those without these behaviors. CONCLUSIONS: Depressive symptoms co-occurred frequently among ATS users in China. The efforts that facilitate drug users' attempts to stop using ATS use and relapse, quit cigarette smoking and stop alcohol drinking during the ATS treatment and management process should be supported as they may contribute to improving the mental health among this population.

[Study of Five STR Loci in A Chinese Han Population.].

To understanding the allele structure and genetic polymorphisms at five STR loci in Chinese Han population, and construct a preliminary database, EDTA-blood specimens were collected from unrelated individuals. DNA samples were extracted with Chelex method and were amplified by PCR technique. The PCR products were analyzed using both PAGE horizontal electrophoresis with discontinuous buffer system and automated fluorescence detection approach. As a result, three STRs consist of simple repeat motifs, while two STR contain a complex repeat structure. The STR polymorphisms at all of the five loci have been observed in Chinese Han population. In a word, the obtained data are beneficial to understanding the population genetics of the five STR loci in Chinese Han population. As a simple approach, the PAGE horizontal electrophoresis can be employed for typing the five STR markers.

[Allele frequencies and species specificity of six short tandem repeat loci in Chinese population].

OBJECTIVE: To develop a set of new markers for forensic application, the authors have chosen 6 short tandem repeat(STR) loci to study the allele frequencies and species specificity in Chinese Han population in Chengdu. METHODS: One hundred and ten EDTA-blood samples were collected from the unrelated individuals in Chengdu city, Sichuan province. DNA was extracted by Chelex-100 and amplified by the polymerase chain reaction(PCR). Polyacrylamide gel electrophoresis (PAGE) and silver staining were used to analyze the PCR products. RESULTS: The polymorphisms of all 6 STR loci have been obtained in Chinese Han population in Chengdu, the alleles of D4S2366, D4S2367, D6S474, D6S1281, D2S1396 and D20S601 being 7, 7, 6, 7, 5, 7, the observed heterozygosity of them being 0.802, 0.708, 0.770, 0.627, 0.542, 0.672, the discrimination power of them being 0.887, 0.828, 0.849, 0.848, 0.794, 0.865; and the power of exclusion of them being 0.602, 0.441, 0.544, 0.325, 0.227, 0.386. Evaluated by comparison with the data from 14 different animals as controls, the 6 STR loci contain good specificity of human beings. CONCLUSION: The 6 STR loci are highly polymorphic and can play a key role in species identification. They are new candidate markers for forensic personal identification and paternity testing.

[Proceedings of human mitochondrial DNA study and its applications to forensic medicine].

The mitochondrial DNA (mtDNA) is a small circular genome located within the mitochondria in the cytoplasm of the cell. Evidence of its existence first arose over 30 years ago. Now the field of the mitochondria is one of the fastest growing disciplines in biomedicine which is driven by fundamentally interesting questions. These questions are mainly about the way of mitochondria evolving and energy producing. In addition, what the consequences of mitochondrial genome mutations in diseases are? How program cell death is regulated? What happens to mitochondria when aging? These questions remain to be answered and the basic understanding of them will contribute to anthropological and forensic analysis, as well as therapy of many diseases. The following review has brought this question to notice by summarizing recent mitochondria research.

[Proceeding of research on X chromosome genetic markers].

The development of Human Genome Project (HGP) makes it possible and more important to reveal the variations or polymorphisms precisely between different individuals and populations. Due to the characters of their high polymorphism and value in disease-linkage analysis as well as pharmacogenomnics, genetic markers on X chromosome have attracted much more attention of current medical and forensic scientists. This report summarized the proceeding of research on X chromosome genetic markers in the clinical and forensic context.