Comparison of STR polymorphism among a Kirgiz ethnic group from Sinkiang and other groups

Objective To study the genetic relationship between Kirgiz individuals living in Sinkiang China and analyze the difference among Kirgiz and the other population with STR polymorphisms.Methods PCR amplification was performed using PE9700,the PCR products were typed by automated sequencer and genescan.Results A database of nine STR loci of Kirgiz was established.It shows there are at least 73 STR alleles and 191 genotypes in Kirgiz.Genotype frequencies distribution showed no deviation from Hardy-Weinberg equilibrium by χ2-test.Kirgiz was compared with the other Chinese ethnic groups,then the American Black and the White.Conclusion These results suggested that the nine STR loci and Amelogenin locus were very useful in human identification,biological archaeology and gene resource studies.

REPORT OF HLA DISTRIBUTION IN 2315 VOLUNTEER DONORS OF CHINESE BONE MARROW BANK FROM NORTHWEST CHINA

Objective To report the HLA data of volunteer donors of Chinese bank from Northwest China and characterize the distribution of HLA genes in Northwest China. Methods HLA-A, B antigens of 2315 volunteer donors were examined by the method of microlymphocytetoxicity (MLT) test .The antigen frequencies(AF) were assessed by directly counting; and based on that gene frequencies(GF) were calculated. HLA data from other population were collected and distribution characteristics were compared. With the raw data, Hardy-Weinberg equilibrium, statistical parameters of forensic medicine interest for HLA were computed. Results A total of 18 specific antigens were detected in HLA-A and the most frequent antigen was A2 . AF and GF were 0.5136 and 0.3026, respectively. A total of 42 specific antigens were detected in HLA-B and the most frequent antigen was A13. Its' AF and GF were 0.1978 and 0.1044, respectively. The heterozygosity(H), polymorphism information content(PIC), discrimination power(DP) and probability of paternity exclusion (PPE) of HLA-A were 0.8215, 0.8212, 0.9356 and 0.7798 accordingly; while H,PIC, DP and PPE of HLA-B were 0.9322, 0.9322, 0.9878 and 0.9528. Conclusion The polymorphism of HLA-A,B genes is characteristic in Chinese. In this research, the genetic trait of HLA in 2315 volunteers is consistent with Northern Han population.

Touch DNA of Shed Skin Cells from the Deployed Airbag to Address Drunken Driving Crimes

In the criminal cases of driving under the influence(DUI), DNA evidence can be collected from the deployed airbag of the motor vehicle and submitted to the crime lab for touch DNA analysis.The evidence can be acquired when the skin cells are observed on the surface of the airbag in a traffic accident. However, the low quantity or quality of the evidence collected from a crime scene prevents further identification analysis in many cases. In the current study, we reported a case of identifying touch DNA extraction from the shed skin cells from the deployed airbag of a motor vehicle. We managed to collect DNA evidence from the shed skin cells in an airbag using a proper approach of collection and extraction. The 5.87 ng of extracted DNA was sufficient for genotyping and forensic identification, which helped to identify the driver of the car in collision with a pier in the street. In DUI cases and other traffic accidents, therefore, the amount of touch DNA extracted from the deployed airbag can be sufficient for DNA marker genotyping and further analysis.

Ratiometric fluorescence probe for accurate detection of Concanavalin A by coupling fluorescent microsphere with boric acid functionalized carbon dots

Accurate and sensitive strategies for Concanavalin A(Con A)sensing are conducive to the better cognition of various important biological and physiological processes.Here,by designing dextran-functionalized fluorescent microspheres(DxFMs)and boric acid-modified carbon dots(BCDs)as recognition unit and built-in signal reference respectively,a ratiometric fluorescent detection platform was proposed for Con A detection with high reliability.In this protocol,the BCDs/DxFMs precipitation was formed due to the covalent interactions between cis-diol of DxFMs and boronic acid groups of BCDs,thus only fluorescence of BCDs could be detected in the supernatant.When Con A was presented,it could bind to DxFMs through its carbohydrate recognition ability and suppress the subsequent assembly between DxFMs and BCDs,leading to the simultaneous capture of DxFMs and BCDs fluorescence in the supernatant.Since the BCDs content was superfluous,their fluorescence intensities were basically constant in all cases.Based on the unchanged BCDs fluorescence signal and target-dependent DxFMs fluorescence signal in supernatant,the ratiometric detection of Con A was realized.Under optimized conditions,this ratiometric fluorescent platform displayed a linear detection range from 0.125μg/mL to 12.5μg/mL with a detection limit of 0.089μg/mL.Moreover,satisfied analytical outcomes for Con A detection in serum samples were obtained,manifesting huge application potential of this ratiometric fluorescent platform in clinical diagnosis.

Research progress in the estimation of the postmortem interval by Chinese forensic scholars

The determination of time since death or the postmortem interval(PMI)is one of the most important and frequently asked questions in forensic medicine.Medicolegal scholars and forensic pathologists around the world have studied the estimation of PMI extensively in the past,and many novel methods and advanced technologies have now been applied in the field.For several centuries,Chinese forensic examiners have also worked on the estimation of the PMI,and there are a large number of excellent studies published in Chinese rather than in English,and these are not easily accessible or known internationally.Therefore we have conducted a review of relevant studies published by Chinese forensic scholars in the last few decades.The scope of this review is to provide a concise summary of the current progress in the estimation of PMI by Chinese forensic researchers using molecular biology,spectroscopic technology,entomological methods,energy changes,thanatochemistry and other methods.

Development of forensic standards in China: a review

Forensic science is crucial for the administration of justice and case investigation.in China,political-legal organizations,including the courts,public security,procuratorate,and judicial administration,developed their own forensic practices before 2004.As a result,the frequent and repeated appraisals undermined judicial authority and credibility.Thus,a law was published in 2005 to improve the uniform forensic management system by the Standing Committee of the National People’s Congress,leading to the establishment of the Forensic Administration of the Ministry of Justice in 2006.During this process,the increased accreditation and interflow highlighted the role of consensus in forensic standards for forensic service providers to avoid uncertainty regarding the methods used and interpretation of results.in 2017,a policy document was promulgated again to strengthen the importance of the uniform standards,which also proposed to establish a new national technical committee for the standardization of forensic science by the General Office of the State Council.in 2018,despite the continuing problems concerning uniformity,the Forensic Administration of the Ministry of Justice was merged into the Public Legal Services Administration.Yet,there is still a long way to go for the national technical committee for the standardization of forensic science.This paper analyses the evolution of forensic standards internationally and nationally,discusses the existing problems,and proposes relative solutions.Moreover,it discusses the future of standards development with the deepening of the reformation of both the national standardization and judicial system.

Photoluminescence Properties and Energy Transfer from Ce^(3+) to Tb^(3+) in Zn_2SiO-_4 Host

Zn2Si O4︰Tb^3＋, Zn2 Si O4︰Ce^3＋, Zn2 Si O4︰Tb^3＋, Ce^3＋ phosphors were prepared by solidstate reaction at 1 150 ℃ for 2h under a weak reducing atmosphere. Moreover, the XRD patterns and photoluminescence spectra were recorded and the effects of Tb3＋ and Ce3＋ concentration on the luminescent properties of as-synthesized phosphors were investigated. The emission spectra under ultraviolet light（333 nm） radiation showed a dominant peak at 542 nm attributed to the 5D4→7F5 transition of Tb^3＋, which was enhanced significantly（about 45 times） by the co-doping of Ce^3＋, indicating that there occurred an efficient energy transfer from Ce^3＋ to Tb^3＋. According to the Dexter＇s energy transfer formula of multipolar interaction, it was demonstrated that the energy transfer between Ce3＋ and Tb3＋ was due to the electric dipolar-dipolar interaction of the resonance transfer.

Relationships between Diatom Abundances in Rat Organs and in Environmental Waters

Objective:A diagnosis of drowning remains one of the most challenging issues in forensic science,especially for decomposed bodies.Diatom analysis is considered as an encouraging method for diagnosing drowning.In this study,we developed a drowned rat model using different diatom densities in water.Methods:A total of 120 adult Sprague-Dawley rats were used and divided into six groups,wherein experimental groups 1-5 were drowned rats(group A)and postmortem submersion rats(group B)that were submerged in water with five different Cyclotella sp.diatom densities,while the remaining group was used as a blank control.The combination of microwave digestion and vacuum filtration method was used to accomplish efficient tissue digestion and ascertain higher accuracy of diatom determinations within organs.Results:The abundances of diatoms in the lungs,livers,and kidneys were significantly different.The diatom abundances in the lungs,livers,and kidneys were directly proportional to the water diatom densities,and specific quantitative relationships could be approximated by separate regression equations for each organ type.However,the trends associated with the diatom increases among organs slightly differed.In addition,the diatom abundances in the lungs,livers,and kidneys were all positively correlated.Diatoms were not observed in the postmortem submersion groups nor in the blank control groups.Conclusion:The results of this study provide valuable information for establishing a quantitative diatom framework for informing future forensic medicine efforts.

MITOCHONDRIAL DNA POLYMORPHISM IN CONTROL REGION FROM CHINESE YUGU POPULATION

Objective To investigate the mitochondrial DN A sequence polymorphism sites in Chinese YUGU ethnic group and to provide basic da ta used in forensic purpose. Methods Genomic DNA was extracted from the hole blood of 100 unrelated individuals of Chinese YUGU ethnic group by standard chelex-100 method. The sequence polymorphism sites was determined by PCR amplification and direct sequencing. Results 54 polymorphic sites were noted in mtDNA np16091-16418 region, and 46 haplotypes were identifi ed. The genetic diversity was calculated to be 0.9691, and the genetic identity was calculated to be 0.0406. Conclusion There are some particul ar polymorphism sites in Chinese YUGU ethnic group. The results suggest that seq uence polymorphism from np16091-16418 in human mitochondrial DNA can be used as a biological marker for forensic identity.

USING STR POLYMORPHISM TO STUDY THE GENETIC RELATIONSHIPS AMONG A CHINESE KOREAN POPULATION AND OTHER GROUPS

Objective To discuss the genetic relationship between Chaoxian and the other populations with STR polymorphisms, and study the origination of Chaoxian with historical data, analyze the difference among them. Methods Samples were obtained from 91 unrelated individuals of Jilin province. PCR amplification was performed using PE9700, the results were analyzed with the GeneScan software and then using the Genetic Analyzer ABI377 and Genotyper2.5. Tests for Hardy Weinberg equilibrium (HWE) and the clustering map were carried out using SPSS11.5. The DA (genetic distance) according to Nei's was calculated and a phylogenetic tree based on the neighbor-joining method using Mega2 software package was constructed. Results 81 alleles and 196 genotypes were observed, with the corresponding frequencies ranging from 0.0055 to 0.4615 and 0.0110 to 0.2747, the observed and expected of genotypes were evaluated using χ 2-test and all of the loci were in accordance with Hardy Weinberg equilibrium (P> 0.05). Chaoxian was clustered with the other Chinese ethnic groups, then the American Black and the White; it was clustered with the Baishan Han, the Beijing Han of China first, then the South Korean. Conclusion The differentiation among races is larger than that among minorities, and, the differentiation among minorities is related to and is consistent with their geographic location.

Application and Prospect of Postmortem Imaging Technology in Forensic Cardiac Pathology:A Systemic Review

Postmortem imaging(PMI)technology known as virtual autopsy or virtopsy is regarded as a useful method of noninvasive or minimally invasive autopsy in forensic practice.Postmortem computed tomography is applicable to traumatic investigation,acute hemorrhage,pulmonary parenchyma disease,calcification(calculus,atherosclerosis),and gas accumulation.Postmortem magnetic resonance(PMMR)has been proven to have advantages in soft tissue identification.Cardiac death is one of the keys and difficult points in forensic practice.With the introduction and development of PMCT angiography and PMMR,it was proved to be a very promising tool in the investigation of cardiac death,including vascular cavities and ischemic myocardium.This article reviewed the applications of the latest PMI and its related technologies in forensic cardiac pathology,including advantages,limitations,and development prospects.

A Future Perspective in Forensic Medicine in China:Diatomological Mapping of Water Bodies

Diatom test(forensic diatomology)is commonly considered as the“gold standard”in the diagnosis of drowning in forensic practices.The diatomology contributes significantly not only in determining the mode of death but also in determining the site of drowning because of various distribution characterizations of diatoms in different water bodies or different seasons.Hence,it is believed that diatomological mapping will be interest to forensic pathologists in the future development.Here,we reviewed the all the studies on the distribution characterizations of diatoms in different water bodies in China recently.The present paper summarized the current situation and the limitations of the previous studies.Moreover,we suggested that it was necessary to establish a systematized and standardized diatomological mapping program nationwide.Our study also encourages diatomological mapping for forensic characterization of water bodies for a prolonged time.

Major depressive disorder:hypothesis,mechanism,prevention and treatment

Worldwide,the incidence of major depressive disorder(MDD)is increasing annually,resulting in greater economic and social burdens.Moreover,the pathological mechanisms of MDD and the mechanisms underlying the effects of pharmacological treatments for MDD are complex and unclear,and additional diagnostic and therapeutic strategies for MDD still are needed.The currently widely accepted theories of MDD pathogenesis include the neurotransmitter and receptor hypothesis,hypothalamicpituitary-adrenal(HPA)axis hypothesis,cytokine hypothesis,neuroplasticity hypothesis and systemic influence hypothesis,but these hypothesis cannot completely explain the pathological mechanism of MDD.Even it is still hard to adopt only one hypothesis to completely reveal the pathogenesis of MDD,thus in recent years,great progress has been made in elucidating the roles of multiple organ interactions in the pathogenesis MDD and identifying novel therapeutic approaches and multitarget modulatory strategies,further revealing the disease features of MDD.Furthermore,some newly discovered potential pharmacological targets and newly studied antidepressants have attracted widespread attention,some reagents have even been approved for clinical treatment and some novel therapeutic methods such as phototherapy and acupuncture have been discovered to have effective improvement for the depressive symptoms.In this work,we comprehensively summarize the latest research on the pathogenesis and diagnosis of MDD,preventive approaches and therapeutic medicines,as well as the related clinical trials.

Vitality and wound-age estimation in forensic pathology:review and future prospects

Determining the age of a wound is challenging in forensic pathology,but it can contribute to the reconstruction of crime scenes and lead to arrest of suspects.Forensic scholars have tended to focus on evaluating wound vitality and determining the time elapsed since the wound was sustained.Recent progress in forensic techniques,particularly high-throughput analyses,has enabled evaluation of materials at the cellular and molecular levels,as well as simultaneous assessment of multiple markers.This paper provides an update on wound-age estimation in forensic pathology,summarizes the recent literature,and considers useful additional informa-tion provided by each marker.Finally,the future prospects for estimating wound age in foren-sic practise are discussed with the hope of providing something useful for further study.

Genetic Polymorphisms of Nine X-STR Loci in Four Population Groups from Inner Mongolia, China

Nine short tandem repeat （STR） markers on the X chromosome （DXS101, DXS6789, DXS6799, DXS6804, DXST132, DXST133, DXS7423, DXS8378, and HPRTB） were analyzed in four population groups （Mongol, Ewenki, Oroqen, and Daur） from Inner Mongolia, China, in order to learn about the genetic diversity, forensic suitability, and possible genetic affinities of the populations. Frequency estimates, Hardy-Weinberg equilibrium, and other parameters of forensic interest were computed. The results revealed that the nine markers have a moderate degree of variability in the population groups. Most heterozygosity values for the nine loci range from 0.480 to 0.891, and there are evident differences of genetic variability among the populations. A UPGMA tree constructed on the basis of the generated data shows very low genetic distance betweent Mongol and Han （Xi＇an） populations. Our results based on genetic distance analysis are consistent with the results of earlier studies based on linguistics and the immigration history and origin of these populations. The minisatellite loci on the X chromosome studied here are not only useful in showing significant genetic variation between the populations, but also are suitable for human identity testing among Inner Mongolian populations.

Diagnosis of coronary artery disease using targeted post-mortem computed tomography coronary angiography:a case report

Targeted post-mortem computed tomography(PMCT)combined with coronary angiography has the potential to play a significant role in the investigation of sudden cardiac death.The authors utilized a targeted PMCT coronary angiography in a case involving a 53-year-old man who died from acute myocardial ischemia and cardiac decompensation which may result from coronary artery disease(CAD).The victim collapsed suddenly at work and died soon after arrival to hospital.The body was examined using PMCT and targeted PMCT coronary angiography.The left anterior descending coronary artery exhibited 75%-100%stenosis in the middle segment;however,the distal segment could not be clearly visualized.In addition,the left circumflex and right coronary artery exhibited calcification,atherosclerosis and an area of 50% stenosis.Signs of cardiogenic pulmonary oedema were also identified.The imaging results suggested that this individual had coronary atherosclerosis and probably died from CAD.The autopsy and histological examination revealed acute myocardial ischemia and myocardial scarring,confirming the cause of death while excluding other probabilities.In summary,targeted post-mortem computed tomography angiography(PMCTA)can visualize the arteries and estimate the degree of principal pathological changes.This method is a simple,reliable and sensitive technique for identifying the presence of coronary atherosclerosis.It is a valuable post-mortem forensic imaging method and should be recommended in the investigation of suspicious cardiac deaths.

Blue light-induced rare-earth free phosphors for the highly sensitive and selective imaging of latent fingerprints based on enhanced hydrophobic interaction

The demand for in-situ detection of latent fingerprints(LFPs)in ways of high sensitivity,high selectivity,high contrast,low cost and user-friendly is still urgent.To overcome this challenge,a moisture-stable,red-emitting fluoride phosphor K_(3)AlF_(6):Mn^(4+)(KAF:Mn^(4+))with an organic hydrophobic skin was prepared.The phosphor has a uniform and superfine morphology with excellent luminescence properties.More importantly,this non-ultraviolet(UV)or non-near infrared(NIR)induced phosphor was proved to be an ideal fluorescent label for LFP imaging,which is both friendly for touch DNA analysis and compatible to forensic light sources.The well-defined ridge details with little background interference on various surfaces were presented by the oleic acid(OA)modified KAF:Mn^(4+)(KAF:Mn^(4+)-OA)phosphor in few seconds using the powder dusting method.To confirm the high selectivity of KAF:Mn^(4+)-OA for LFP imaging,an efficient quantitative evaluation method is proposed with the aid of ImageJ&Origin software.Due to the superiority of the Mn^(4+)-doped fluoride for the rapid imaging of LFPs in terms of lowcost,high compatibility and good availability,it is expected to be a promising candidate for forensic science as well as fluorescence imaging in other fields instead of rare earth luminescent materials.

Dynamic changes of serum protein in rats with acute intoxication of Chinese cobra snake venom by proteomic analysis

To elucidate the toxic mechanism of snake venom at the protein level,proteomics technol-ogy was applied to investigate the effect of venom on circulation in the mammalian body.Temporal proteomic analysis was performed to profile the dynamic changes in the sera of Sprague-Dawley rats administered with Chinese cobra venom or saline.Using 8-plex iTRAQ analysis,392 and 636 serum proteins were identified to be linearly upregulated or downre-gulated over time in the low-dose group and high-dose group,respectively.These proteins were mainly associated with the acute phase response pathway,complement system,and liver X receptor(LXR)/retinoid X receptor(RXR)and farnesoid X receptor(FXR)/RXR activation pathways.Compared with the low-dose group,the immune response and integrin pathways were inhibited in the high-dose group,although no obvious effect was observed.With con-sistently higher or lower expression in the high-dose group compared to the low-dose group throughout the whole process of venom poisoning,two proteins,Kininogen-1(KNG1)and orosomucoid 1(ORM1),which are involved in metabolism and immune response,occu-pied a core position in the pathway network and are considered venom dose-dependent biomarker candidates.

Multiple regression analysis of the craniofacial region of Chinese Han people using linear and angular measurements based on MRI

The purpose of this study was to measure the craniofacial region of Chinese Han people in the linear and angular dimensions,and to analyse the effects on sex,age and body parameters(height and weight).All 250 individuals(86 males,164 females)underwent a three-dimensional magnetic resonance imaging(MRI)scan,and the MRI data were imported into VG Studio MAX 2.2 software.Each linear and angular measurement in the craniofacial region was processed directly.Using SPSS 20.0 software,nine multiple regression equations were constructed,and all the adjusted R^(2) values were statistically significant(0.031-0.311).Multiple regression analysis showed that most craniofacial measurements of Chinese people were significantly correlated with height,weight or age.The multiple regression equations constructed will be helpful in anthropometric analysis and forensic inference.

Profile Interpretation of Extremely Long Alleles at DYF387S1 and DYS447 Migrated into Allele Range of Adjacent Loci

Two rare cases of long alleles at Y‑chromosome short tandem repeat(Y‑STR)loci(DYF387S1 and DYS447)were identified when two father-son pairs were analyzed by multiplex amplification.“Null alleles”were observed at DYF387S1 and DYS447,and duplicated alleles were displayed at DYS533 and DYS19.We secondly amplified DYF387S1,DYS533,DYS447,and DYS19 loci by singleplex polymerase chain reaction(PCR)and sequence analysis of the long alleles at DYF387S1 and DYS447 loci.The results showed that alleles from DYF387S1(allele 55)and DYS447(allele 41)were longer than their common sizes in the allelic ladder ranges(33-42 for DYF387S1 and 18-30 for DYS447)and located in the neighboring loci(DYS533 and DYS19,respectively).Therefore,to identify these cases involving this unusual phenomenon,not only re‑amplification using the same kit but also additional amplification(using alternative multiplex kits with different adjoining markers or additional singleplex PCR amplification)should be performed to avoid misinterpreting Y‑STR profiles.