riteria as well as its role in sudden cardiac death and discusses the potential application, to provide reference for relevant research and application.
  Objective To explore the application value of automatic nucleic acid extractor combined with vacuum concentrator in forensic DNA extraction. Methods Gradient samples of human peripheral venous blood were collected at 40, 80, 120, 160, 200, 240, 280 and 320 fold dilution. The samples of each gradient were treated with no inhibitor, black oil, rust, fruit acid, tin foil and indigo, respectively. The automatic nucleic acid extractor was used for DNA purification and extraction of the above samples. The extracted DNA eluent （6 μL） was taken for amplification directly, and the rest was concentrated by vacuum concentrator. DNA was amplified and examined using the Investigator 26plex QS kit before and after concentration. Results Only gradient samples treated with fruit acid obtained complete STR typing results at 40 fold dilution. The other 5 methods obtained complete STR typing results at 40-160 fold dilution. The results of STR typing after DNA concentration showed that the average peak height and detection ratted by vacuum concentrator. DNA was amplified and examined using the Investigator 26plex QS kit before and after concentration. Results Only gradient samples treated with fruit acid obtained complete STR typing results at 40 fold dilution. The other 5 methods obtained complete STR typing results at 40-160 fold dilution. The results of STR typing after DNA concentration showed that the average peak height and detection rates of gene loci both increased to a certain extent, but the effect was not obvious. Conclusion The automatic nucleic acid extractor has an efficient inhibitor removal ability and high extracting efficiency of DNA. The vacuum concentrator can concentrate DNA samples to a certain extent. Combining the automatic nucleic acid extractor with the vacuum concentrator can improve the examination success rate of forensic materials.
  Objective To study the imaging characteristics of maxillary sinus effusion in drowned bodies, to explore its morphological characteristics and value in the diagnosis of the cause of death, and to provide objective evidence to support the study of virtual anatomy of drowning. Methods The 154 postmortem CT examination cases （31 cases of drowning, 123 cases of non-drowning） of Beijing Public Security Bureau Forensic Center in 2019 were collected. The bodies of all cases were scanned by multi-layer spiral CT before double-blind reading by clinical imaging experts.  https://www.selleckchem.com/products/alkbh5-inhibitor-2.html  Maxillary sinus of corpses with maxillary sinus effusion in imaging findings was punctured. The detection rate of maxillary sinus effusion was calculated. The CT value and volume of maxillary sinus effusion were measured on 3D DICOM workstation. Results The detection rate of maxillary sinus effusion in the drowning was 100%, the shape was horizontal liquid level, the volume was 1.2-11.2 mL, the CT value was 6.08-19.02 Hu, with an average value of 12.8nus effusion in the bodies in water, which can be an auxiliary examination method for identification of drowning.
  Objective To study the DNA methylation of nucleated cells in peripheral blood of patients died from anaphylactic shock caused by cephalosporin drugs and to provide a new research direction and basis for the forensic diagnosis of shock caused by drug hypersensitiveness. Methods Methylation microarray was used to detect DNA methylation of nucleated cells in peripheral blood of patients died from anaphylactic shock caused by cephalosporin drugs and normal subjects. Sequencing data and chip data were analyzed for differences in DNA methylation using R language methylkit, ChAMP package. Random forest algorithm was used to evaluate the importance of the DNA methylation differential sites. Results Differential sites of DNA methylation highly associated with anaphylaxis caused by cephalosporin drugs were obtained at loci such as 
  , 
  and 
  . Conclusion Cephalosporin allergy is associated with DNA methylation, and DNA methylation may be a new strategy for forensic identification of anaphylactic shock and death.
 Ob.
  Objective To retrospectively analyze the characteristics of the traumatic rupture of intracranial internal carotid artery in order to provide reference for forensic expertise examination and identification. Methods A total of 11 autopsy cases of traumatic rupture of intracranial internal carotid artery were collected. The gender, age, cause of injury, blood loss on the scene, location of internal carotid artery rupture, hardening degree of the rupture of the wall, brain injury, blood ethanol content and cause of death were also recorded. Results All 11 cases died on the scene, of which 7 died from traffic accidents, 2 falls from height and 2 from bare handed injuries. None of the 11 victims suffered serious head and body surface injury. The internal carotid artery rupture in the 9 cases of traffic injury and fall from height injury occurred in the cavernous segment. In all these cases, there were transverse fractures of the middle cranial fossa with the carotid sulcus involved, and minor intracranial hemorrckness rupture of the vessel wall, and the long axis of the wounds was perpendicular to those of the artery. Conclusion The incidence of intracranial internal carotid artery rupture in high-energy trauma events such as traffic accidents and high falls deserves attention. Injuries of the cavernous segment or ophthalmic segment might be more common. The main injury mechanism of intracranial internal carotid artery rupture might be that the blood vessels were pulled and the bone fragments caused damage.
  Objective To conduct bibliometric analysis of forensic genetics literatures published by Chinese mainland scholars in SCIE journals from 1989 to 2019, to show the research achievements of the past three decades and predict future research fields and directions. Methods Microsoft Office Excel 2019 was utilized to analyze the general situation, research institutions, authors, funds, author keywords, etc. of the literatures. The status of research in forensic genetics in Chinese mainland was visualized by PlotDB, Gephi 0.9.2 software and literature interpretation. Results During the last three decades, 1 126 forensic genetics literatures were published by scholars from Chinese mainland on SCIE journals, mostly articles. The quantity and quality of the literatures were both on the increase. The number of literatures published in 
  was the highest, and 60.83% of the literatures were funded, mainly by the National Natural Science Foundation of China （498 literatures）. The current research hotspots were STR, SNP, InDel polymorphisms, linkage genetic markers, mtDNA genetic markers, epigenetic markers, RNA genetic markers, chip technology and omics research method.