Effects of Signaling Activation of Bone Morphogenetic Protein 2 on the Differentiation and Infiltration of Regulatory T Lymphocytes in Tumors / 中国医学科学院学报

Objective To determine whether the signaling activation of bone morphogenetic protein 2(BMP2)can induce myeloid-derived suppressor cells(MDSC)to secret transforming growth factor β(TGF-β),further enhancing the differentiation and infiltration of regulatory T lymphocytes(Treg)into tumor tissue. Methods The BMP2-induced mRNA and protein expression of TGF-β in MDSC was detected by quantitative real-time polymerase chain reaction and enzyme-linked immunosorbent assay(ELISA),respectively.The effect of BMP2-induced TGF-β secretion by MDSC on Treg differentiation was then determined by flow cytometry.Finally,we implanted the recombined human bone morphogenetic protein 2(rhBMP2)collagen gels into tumor-burdened mice to examine the role of BMP2 in Treg differentiation via MDSC-secreted TGF-β

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.

Advances in the studies of postmortem interval estimation by the levels of chemical components in human vitreous humor after death / 法医学杂志

Estimation of postmortem interval (PMI) is one of the problems that need to be solved for forensic examination of the dead body. Accurate estimation of PMI has great values to criminal investigation and trial. The levels of chemical components in human vitreous humor are changed with time after death, which can help estimate the PMI. The levels of certain chemical components, such as potassium, magnesium, ammonia, urea, creatinine, uric acid, hypoxanthine, lactic acid and so on, in human vitreous humor will gradually increase with time after death, while others such as calcium, sodium, enzymes, glucose, vitamin C and so on will decrease. The updates and advances in those studies were reviewed in this article.

Relationship between CO II gene of mtDNA of Lucilia sericata and latitude interval / 法医学杂志

OBJECTIVE@#To deduce the region that the geographical species of Lucilia sericata come from and determine the scene of crime (SOC) based on the gene analysis of mtDNA CO II.@*METHODS@#A 635 bp region for CO II of 4 Lucilia sericata (belong to 2 geographical species) were collected and sequenced, compared with the data of GenBank. A neighbour-joining tree with the Tamura and Nei model was constructed by MEGA2.1 package. The number of inherit intervals of inner-species were analyzes by Kimura's two-parameter model and used for construction the relationships between hereditary and latitude interval by SPSS10.5 soft.@*RESULTS@#It showed that they had the relationships between inherit and latitude interval for the 8 geographical species of Lucilia sericata for CO II.@*CONCLUSION@#This method can be the evidence deducing the region that the geographical species of Lucilia sericata come from and further to determine the scene of crime (SOC).

Advances of forensic entomology in China / 法医学杂志

Forensic entomology is a branch of forensic medicine, which applies studies of insects and arthropods to getting evidence for court and has an analogous advantage in the estimation of the postmortem interval (PMI) and other questions of forensic relevance. The paper expounds its definition and contents and reviews some progress of the studies in some aspects in China such as the constitution and succession of insect community on the different cadavers, the applications of morphological features of insects and the technology of analysis of deoxyribonucleic acid (DNA) in forensic entomology, and forensic entomological toxicology etc.