Prospects of Application of Microbial Biofilm to Estimate PMI of Corpses in Water / 法医学杂志

In forensic pathology, the estimation of postmortem interval （PMI） has always been a difficult issue, and there is still lack of effective methods to estimate PMI of corpses in water. Microbial biofilm refers to the microbial population attached to non-biological or biological surfaces by microorganisms during microbial growth, that has a three-dimensional structure, surrounded by extracellular polymers and matrix networks created by itself. A series of community succession phenomena of microorganisms occur during the occurrence and development of microbial population. The microbial community and its succession process of this kind of biofilm attached to the surface of a corpse in water may become a new basis for estimation of the PMI of corpses in water. This review elucidates on the concept, classification, research methods, and influencing factors of biofilm and analyzes its application prospects in PMI estimation of corpses in water, which would provide new ideas for the researches in this field.

Research Progress of Aquatic Corpse Decomposition and Postmortem Submersion Interval Estimation / 法医学杂志

Human corpses can be found in a variety of aquatic environments. The decomposition of corpses in aquatic environments is different from those on land. A large number of factors influence the decomposition process in water, therefore postmortem submersion interval （PMSI） is difficult to estimate. To date, while studies on aquatic corpses are obviously fewer than those on terrestrial corpses, there are many problems in practical work. This review summarizes the stages and influencing factors of aquatic corpse decomposition, and introduces the relevant research progress of PMSI estimation based on decomposition stages, postmortem phenomena, aquatic insects, biofilm, and physical and chemical methods, in order to provide reference for aquatic decomposition researches and practices.

Retrospective Analysis on 1 900 Cases of Medical Malpractices / 法医学杂志

Objective To study the change trend, distribution characteristics and causes of medical malpractices in 18 years, through retrospective analysis of 1 900 cases of medical malpractices, in order to provide guidance for the precaution and the treatment of medical malpractices. Methods A thousand and nine hundred medical malpractice cases that were accepted by Hunan Xiangya Judical Identification Center from 2000 to 2017 were collected. Statistical analysis on the caseloads, the clients, the department distributions, the levels of the hospital and the causes of medical malpractices, etc were conducted. Results The number of cases commissioned by third-party accreditation agencies for medical fault identification was on the rise; The clients of medical malpractices changed significantly in 18 years. Most of the medical malpractice cases occurred in secondary and tertiary hospitals, significantly more in surgery, obstetrics and gynecology. The occurrence of medical malpractices was related to the doctor's insufficient prediction of the severity of the disease and the possible complications, and failure to fully inform the relevant duty of care, etc. Conclusion China's medical malpractice solutions and medical fault identification procedures are gradually improving. Strengthening the medical malpractice precaution awareness of medical workers in surgery, obstetrics and gynecology will be conducive to resolution of medical malpractices.

Research Progress of Vitreous Humor Detection Technique on Estimation of Post-mortem Interval / 法医学杂志

Estimation of postmortem interval(PMI)plays a crucial role in forensic study and identifica-tion work. Because of the unique anatomy location, vitreous humor is considered to be used for estima-ting PMI, which has aroused interest among scholars, and some researches have been carried out. The detection techniques of vitreous humor are constantly developed and improved which have been gradually applied in forensic science, meanwhile, the study of PMI estimation using vitreous humor is updated rapidly. This paper reviews various techniques and instruments applied to vitreous humor detection, such as ion selective electrode, capillary ion analysis, spectroscopy, chromatography, nano-sensing technology, automatic biochemical analyser, flow cytometer, etc., as well as the related research progress on PMI es-timation in recent years. In order to provide a research direction for scholars and promote a more accu-rate and efficient application in PMI estimation by vitreous humor analysis, some inner problems are also analysed in this paper.

Application of High-throughput Sequencing in Researches of Cadaveric Microorganisms and Postmortem Interval Estimation / 法医学杂志

Necrobiome is the main factor causing the cadaver decomposition. Studying the microbial succession during decomposition is one of the main tasks of forensic microbiology. The interactive relationships among cadaver, environment and microorganisms are complicated. The microbial succession study relies on macroscopic monitoring of community composition and the diversity change in each decomposition stage. With the maturity and development of high-throughput sequencing （HTS）, the structure and diversity of microbial communities in different environments have been successively revealed. A new breakthrough to explore the cadaveric microorganisms has been opened as well. It has become the research hotspots in forensic microbiology to reveal the microbial succession in the process of cadaver decomposition and to interpret the essence of various decomposition phenomena by using HTS, which can provide a new reference for postmortem interval （PMI） estimation. The present paper reviews studies on PMI estimation by using cadaveric microorganism. Problems and application prospects of forensic microbiology studies are discussed on the basis of the current application of HTS technology in the exploration of microbial succession.

Genetic Polymorphisms of 21 STR Loci in Hunan Province-based Han Population / 法医学杂志

OBJECTIVES@#To investigate the genetic polymorphisms of 21 short tandem repeat （STR） loci （D3S1358, D13S317, D7S820, D16S539, Penta E, D2S441, TPOX, TH01, D2S1338, CSF1PO, Penta D, D10S1248, D19S433, vWA, D21S11, D18S51, D6S1043, D8S1179, D5S818, D12S391 and FGA）.@*METHODS@#A total of 560 blood samples were collected from unrelated healthy individuals of Han population in Hunan Province. Chelex-100 extraction method was applied to the extraction of genomic DNA, and an AGCU EX22 Kit and 9700 STR amplification was used in amplification reactions. The products were separated and analyzed on 310 Genetic Analyzer.@*RESULTS@#A total of 248 alleles were observed, the allelic frequencies ranging from 0.001 to 0.518. Observation of genotype distributions for each locus showed no deviations from Hardy-Weinberg equilibrium except Penta E （P=0.023）. The combined power of discrimination, combined power of exclusion, and combined matching probability of the 21 STR loci were approximately 0.999 999 999 999 999 999 999 999 8, 0.999 999 998, and 1.36×10⁻²⁵, respectively.@*CONCLUSIONS@#The 21 STR loci show high polymorphisms in the Han population, which can provide valuable data and a theoretical basis for forensic individual identification and paternity testing.

The Origin and Development of Medical Jurisprudence in Xiangya / 法医学杂志

The origin of medical jurisprudence in China can be traced back to as early as 1920s, and since then, the discipline has undergone a great development. This paper, based on the disciplinary development of medical jurisprudence at Xiangya School of Medicine, illustrates its evolution in three aspects covering the scientific and theoretic foundation, legal system and policy support. The current investigation reflected a glimpse of the modern forensic science in China, providing useful historical reference for the development of Chinese forensic science.

Bacterial Succession on Rat Carcasses and Applications for PMI Estimation / 法医学杂志

UNLABELLED@#Abstract:@*OBJECTIVE@#To investigate the bacterial succession on rat carcasses and to evaluate the use of bacterial succession for postmortem interval (PMI) estimation.@*METHODS@#Adult female SD rat remains were placed in carton boxes. The bacterial colonization of circumocular skin, mouth and vagina was collected to be identified using culture-dependent biochemical methods. The changes in community composition were regularly documented.@*RESULTS@#The bacterial succession in three habitats showed that Staphylococcus and Neisseria were predominated in early PMI, especially Staphylococcus aureus and Neisseria lactamica in 6 hours after death. Lactobacillus casei developed on the 3-4 days regularly, and kept stable at a certain level in late PMI.@*CONCLUSION@#The involvement of normal and putrefactive bacteria in three body habitats of rat remains can be used for PMI estimation.

Genetic polymorphism of nine non-CODIS STR loci in Hunan Province-based Chinese Han population / 法医学杂志

OBJECTIVE@#To determine the allelic frequency distribution and genetic parameters of nine non-CODIS DNA index systems of the short tandem repeat (STR) loci (D2S1772, D6S1043, D7S3048, D8S1132, D11S2368, D12S391, D13S325, D18S1364, and GATA198B05).@*METHODS@#A total of 353 blood samples were collected, extracted, amplified, and analyzed from unrelated healthy individuals of Han nationality in Hunan Province, China.@*RESULTS@#One hundred and fourteen alleles were observed in the population with corresponding allelic frequencies ranged from 0.001 0 to 0.323 0. For all the nine non-CODIS STR loci, the observed genotypic data showed no significant deviations from the Hardy-Weinberg equilibrium. The Ho, He, PIC, DP, and PE of the studied non-CODIS STR loci ranged from 0.1080 to 0.1950, 0.8050 to 0.8920, 0.7700 to 0.8600, 0.9250 to 0.9660 and 0.6070 to 0.7800, respectively.@*CONCLUSION@#Nine non-CODIS STR loci have high degrees of polymorphisms, which may be useful in individual forensic identification and parentage testing in forensic practice.

Diagnosis of amniotic fluid embolism with blood samples by liquid-based cytology technique / 法医学杂志

OBJECTIVE@#To establish the diagnosis of amniotic fluid embolism with blood samples by liquid-based cytology technique and to study the validity of method.@*METHODS@#The blood samples were collected from patients who suffered from amniotic fluid embolism. The components of amniotic fluid in blood samples were examined with blood smear by two direct smear methods (supernatant smear, sediment smear) and two liquid-based cytology methods (automatic smear, manual smear). The positive detection rate of each method was calculated.@*RESULTS@#The positive detection rates of two liquid-based cytology methods (84.6% and 92.3%, respectively) were much higher than those of two direct methods (53.8% and 61.5%, respectively).@*CONCLUSION@#The liquid-based cytology technique could improve the positive detection rate of amniotic fluid embolism.

Tuberculous abdominal aortic aneurysm with alimentary tract hemorrhage: a case report with medico-legal implications / 法医学杂志

An autopsy case of sudden death induced by alimentary tract hemorrhage was presented, which was caused by the unexpected rupture of clinically unrecognized tuberculous abdominal aortic aneurysm (TAAA). The initial diagnosis was made of the syndrome of coronary heart disease and hypertensive disease. The detailed autopsy showed that the alimentary tract hemorrhage was caused by a sudden rupture of the mass after posture changing was ascertained as the cause of death. The diagnosis of TAAA was determined by the autopsy findings. Analysis for the medical dispute of TAAA was described, and the difficulty of the diagnosis and medico-legal implications were also discussed.

Reflection of estimating postmortem interval in forensic entomology and the Daubert standard / 法医学杂志

Estimating postmortem interval (PMI) is always the emphasis and difficulty in forensic practice. Forensic entomology plays a significant indispensable role. Recently, the theories and technologies of forensic entomology are increasingly rich. But many problems remain in the research and practice. With proposing the Daubert standard, the reliability and accuracy of estimation PMI by forensic entomology need more demands. This review summarizes the application of the Daubert standard in several aspects of ecology, quantitative genetics, population genetics, molecular biology, and microbiology in the practice of forensic entomology. It builds a bridge for basic research and forensic practice to provide higher accuracy for estimating postmortem interval by forensic entomology.

Identification of sarcosaphagous Calliphorid flies by analyzing the sequence of 16S rDNA / 法医学杂志

OBJECTIVE@#To explore the application of a 289bp fragment of the 16S rDNA gene to identify various species of sarcosaphagous Calliphorid flies.@*METHODS@#Twenty-six Calliphorid flies were collected from 14 Chinese provinces. All specimens were properly assigned into three genera and six species. The DNA of the pectoralis was extracted using CTAB method. Then PCR amplification was done for the 289 bp fragment of the 16S rDNA gene. The PCR products were then purified and sequenced, and the obtained sequences were uploaded to GenBank. The phylogenetic tree was built by the neighbor-joining method and intraspecific and interspecific divergences were calculated by sequence analysis.@*RESULTS@#The above 26 sarcosaphagous flies could be well clustered according to different genera and species. The evolutional intraspecific values were all zero, the evolutional interspecific variations varied from 0.3% to 6.5%.@*CONCLUSION@#The 289 bp fragment of the 16S rDNA of sarcosaphagous flies can be effectively used to identify most of the flies at species level. This method appears to be fast and low dissipative, which might be used to estimate postmortem interval by sarcosaphagous flies.

Degenerate oligonucleotide primed-PCR technology establishment and its sensitivity test analysis / 法医学杂志

OBJECTIVE@#To establish a whole genome amplification testing system based on degenerate oligonucleotide primed-PCR (DOP-PCR) and to explore its reliability and sensitivity.@*METHODS@#DOP-PCR amplified production was detected by fluorescent labeled multiplex STR amplification and capillary electrophoresis detection system to determine reliability and sensitivity of DOP-PCR system.@*RESULTS@#DOP-PCR system was successfully established and the detection sensitivity reached 5 cells (30 pg) by pretreatment of DOP-PCR and then detection of STR genotyping.@*CONCLUSION@#The system established in this study is reliable and more testing sensitive for forensic trace evidence.

Comparison of mtDNA extracting methods for common sarcosaphagous insects / 法医学杂志

OBJECTIVE@#To compare effects of three different methods for mtDNA extraction from common sarcosaphagous insects including cetyl trimethyl ammonium bromide (CTAB) method, sodium dodecyl sulfate-potassium acetate (SDS-KAc) method and sodium dodecyl sulfate-proteinase K (SDS-PK) method.@*METHODS@#Seventy-two insects from four species [Chrysomya megacephala (Fabricius, 1784), Eusilpha bicolor (Fairmaire, 1896), Paraeutrichopus pecoudi (Mateu, 1954), Vespa velutina (Lepeletier, 1836)] were collected from the corpses of the rabbits in Changsha district. The total DNA of above samples was extracted by CTAB, SDS-Kac and SDS-PK methods. The purity and concentration of DNA were examined by protein-nucleic acid spectrophotometry, and mtDNA were amplified by specific primers and PCR products were detected by agarose gel electrophoresis. Then PCR products were sequenced and subsequently up-loaded to GenBank.@*RESULTS@#mtDNA was successfully extracted with three methods from most of the samples. The SDS-PK method was better in DNA purity compared to other methods and the CTAB method was superior in extracting DNA from old samples, while SDS-KAc method showed no significant difference for extraction effects of different samples.@*CONCLUSION@#The most appropriate method should be chosen depending on different situations. SDS-PK method is expected to obtain high-quality DNA, while CTAB method is preferred in extracting obsolete samples. SDS-KAc method is low cost and can be used in various kinds of preliminary experiments.

Application of mtDNA polymorphism in species identification of sarcosaphagous insects / 法医学杂志

Species identification of sarcosaphagous insects is one of the important steps in forensic research based on the knowledge of entomology. Recent studies reveal that the application of molecular biology, especially the mtDNA sequences analysis, works well in the species identification of sarcosaphagous insects. The molecular biology characteristics, structures, polymorphism of mtDNA of sarcosaphagous insects, and the recent studies in species identification of sarcosaphagous insects are reviewed in this article.

Comparison of mtDNA extraction from different parts of sarcosaphagous insects / 法医学杂志

OBJECTIVE@#To explore mitochondrial DNA (mtDNA) extraction effects of different parts from sarcosaphagous insects using improved cetyltriethylammnonium bromide (CTAB) method.@*METHODS@#Thirteen Lucilia sericata (Meigen) and 13 Nicrophorus fossor (Erichson) were collected from the corpses of rabbits placed on the outdoor lawn in Huhehot district. Four parts (head, chest muscle, legs and wings) of insect were collected, and the mtDNA of all samples were extracted using CTAB method. The purity and concentration were tested using protein and nucleic acid spectrophotometry. The integrity of the extracted mtDNA and PCR products were checked by agarose gel electrophoresis. The PCR products were sequenced and the obtained sequences were imputed into GenBank for comparison.@*RESULTS@#mtDNA were successfully extracted from 10 head samples, 6 legs samples, 4 wing samples and 13 chest muscle samples of the Lucilia sericata (Meigen). Also, mtDNA were successfully extracted from 5 head samples, 8 legs samples, 3 wing samples and 13 chest muscle samples of the Nicrophorus fossor (Erichson).@*CONCLUSION@#mtDNA can be obtained from chest muscle and other parts of sarcosaphagous insects using the improved CTAB method.

Advances on study of Lucilia species in estimating postmortem interval in forensic medicine / 法医学杂志

Sarcosaphagous insects are very important to investigate some criminal cases. They are significant useful in estimating post-mortem interval (PMI) and corpse transfer post-mortem. Lucilia are very common sarcosaphagous insects. They like sunshine and are usually the earliest to touch the cadaver. These characteristics and others such as the stages of their larvae development can offer good evidences for criminal case investigation. This paper summarizes details of their application for estimating postmortem interval in recent years and reviews the methods to identify species and to determine the age of adult Lucilia with molecular biology and entomological morphology.

Succession of sarcosaphagous insects at summer and autumn in Shijiazhuang area / 法医学杂志

OBJECTIVE@#To study the succession of sarcosaphagous insects and their regular activity on carcass in Shijiazhuang area.@*METHODS@#Nine rabbits were sacrificed and placed at the same site during June to September in 2007-2009. The common species of sarcosaphagous insects were observed.@*RESULTS@#Nine main species could be identified belonging to 3 families and 4 genera from Diptera, including Musca domestica (Linnaeus), Muscina stabulans (Fall én), Hydrotaea (Ophyra) capensis (Wiedemann), Hydrotaea (Ophyra) spinigera (Stein), Lucilia sericata (Meigen), Chrysomya megacephala (Fabricius), Boerttcherisca Peregrina (Robineau-Desvoidy), Parasarcophaga crassipalpi (Macquart) and Helicophagella melanura (Meigen). Eleven main species belonging to 4 families from Coleoptera include Nicrophorus concolor (Kraatz), Silpha carinata(Herbst), Nicrophorus fossor (Eneshas), Ptomascopus morio (Kraatz), Eusilpha bicolor (Fairmaire), Scarabaeus rugosus (Hausmann), Harpalus rufipes (DeGeer), Dolichus halensis (Schaller), Goncephalum pusillum (Fabricius), Cafius seminitens (Horn) and Aleochara pacifica (Casey). Two main species from 2 families were Tetramorium caespitum (Linnaeus) and Vespa velutina(Lepeletier).@*CONCLUSION@#It is evident that the succession of sarcosaphagous flies in Shijiazhuang with its unique geographical features. It may be used for estimating postmortem interval in Shijiazhuang area.

The succession of sarcophagus beetles on carrion and its application in forensic medicine / 法医学杂志

Sarcophagus beetles, which can not be replaced by Diptera, play a pivotal role not only in estimating PMI of dry human skeletal remains in the later stages decomposition of carcasses, but also the corruption, destruction, decomposition and posture changes of carcasses. This article explicates the succession of sarcophagus beetles on carrion and its influencing factors, and introduces the application and prospects of sarcophagus beetles in forensic entomology. Although few researches focus on sarcophagus beetles at present, it is believed that more and more forensic scientists will pay attention to sarcophagus beetles' application in forensic identification.