DNA quantification of blood samples pre-treated with pyramidon / 法医学杂志

OBJECTIVE@#To study DNA quantification and STR typing of samples pre-treated with pyramidon.@*METHODS@#The blood samples of ten unrelated individuals were anticoagulated in EDTA. The blood stains were made on the filter paper. The experimental groups were divided into six groups in accordance with the storage time, 30 min, 1 h, 3 h, 6 h, 12 h and 24h after pre-treated with pyramidon. DNA was extracted by three methods: magnetic bead-based extraction, QIAcube DNA purification method and Chelex-100 method. The quantification of DNA was made by fluorescent quantitative PCR. STR typing was detected by PCR-STR fluorescent technology.@*RESULTS@#In the same DNA extraction method, the sample DNA decreased gradually with times after pre-treatment with pyramidon. In the same storage time, the DNA quantification in different extraction methods had significant differences. Sixteen loci DNA typing were detected in 90.56% of samples.@*CONCLUSION@#Pyramidon pre-treatment could cause DNA degradation, but effective STR typing can be achieved within 24 h. The magnetic bead-based extraction is the best method for STR profiling and DNA extraction.

Detecting DNA damage of cell in rats using comet assay after tetramine poisoned / 法医学杂志

OBJECTIVE@#To study the damage of DNA in lymphocytes, brain cells and cardiac muscle cells of rats induced by different dose of tetramine and to speculate the toxicant mechanism of tetramine.@*METHODS@#The rat were poisoned by Tetramine, which was taken in by mouth. The rat poisoning models were used by 0.2, 0.1, 0.05, 0.01 mg x kg(-1) Tetramine, and comparison model was made by NS. Lymphocytes and brain cells and cardiac muscle cells of rats were separatd and collected form experimentation rat. DNA damages of cells which were exposed to different doses of tetramine were detected using the single cell gel electrophorresis (SCGE) or comet assay.@*RESULTS@#DNA damages have been observed in lymphocytes, brain cells and cardiac muscle cells of rats which exposed form 0.01mg x kg(-1) doses of tetramine to 0.2mg x kg(-1) doses of tetramine. The test groups are very significantly statistical different to the control group (P<0.01).@*CONCLUSION@#It is assumed that DNA damages of cells might be one of the toxicant mechanism of tetramine.

Reasons why the quality of medico-legal autopsy in the medical tangle varies from two areas / 法医学杂志

OBJECTIVE@#To study reasons that the quality of medico-legal autopsy in the medical tangle varies from different area.@*METHODS@#Collecting the cases of medical tangle in two medico-legal agencies, then counting percent of classes on the ten key-points, analyzing the data of the cases by chi-square test and t-test.@*RESULTS@#It is indicated that the applied methods and standards of the two agencies are different. There are more different in seven keypoint of medicolegal autopsy by chi-square test.@*CONCLUSION@#Six key-points are found to be more important to medico-legal appraiser, standardization of forensic autopsy, standardization of picking up specimen from the body, diagnosis standardization of the cause of death, consultation system and standardization of writing documents on medico-legal autopsy.

The study of status and advances on tetramine poisoning / 法医学杂志

Tetramethylenedisulphotetramine(TETS) is virulent rodenticides which was strictly forbidden to use in China. Poison dose of TETS is very little, LD50 in rats in 0.1 mg/kg. Manifestations and signs of TETS poisoning are showed in 5 min. The long dated effect of poisoning is extremely strict. Mamy studys on TETS are restricted on the treatment of TETS poisoning, while that of poisoning mechanism is very few. This paper reviewed TETS poisoning mechanism, pathological changes and research advances.