Résumé
OBJECTIVE@#To explore the feasibility of real-time RT-PCR of housekeeping mRNA degradation in dead rats in order to seek new suitable techniques for post-mortem interval (PMI).@*METHODS@#The levels of GAPDH mRNA and beta-actin mRNA in the brain and spleen of the rats were measured at different times after death by the SYBR Green I real-time RT-PCR. The relative mRNA level was indicated with the Ct value, then the relationship between the Ct value and PMI were analyzed and the corresponding regression equation was obtained.@*RESULTS@#The Ct values of GAPDH mRNA and beta-actin mRNA by SYBR Green I real time RT-PCR correlated well with the PMI.@*CONCLUSION@#The SYBR Green I real-time RT-PCR is a reliable technique for studying mRNA degradation. Adoption of the housekeeping genes eliminates systematical errors of other genes which have individual difference. As an objective and dynamic indication, Ct value has a good correlation with PMI, and could be applied for estimating PMI, especially in late period.
Sujets)
Animaux , Rats , Actines/génétique , Glyceraldehyde 3-phosphate dehydrogenases/génétique , Modifications postmortem , Stabilité de l'ARN/génétique , ARN messager/métabolisme , Rat Sprague-Dawley , RT-PCR/méthodes , Facteurs tempsRésumé
OBJECTIVE@#To study the relationship between the DNA content in follicular epithelial cells of the human thyroid and postmortem interval (PMI).@*METHODS@#Changes of the DNA content in thyroid follicular epithelial cells at different PMI were determined by Methyl Green-Pyronin (MGP) stain combined with an image analysis technique.@*RESULTS@#The average DNA content in the thyroid follicular epithelial continued to decrease with increased PMI. The coefficient of determination for DNA content with average gray, aimed area, aimed area ratio and positive index in follicular epithelial cells were 0.960, 0.987, 0.988 and 0.990, respectively.@*CONCLUSION@#There is an apparent correlation between the average DNA content of follicular epithelial cells and the PMI. MGP stain combined with an image analysis technique seems to be a useful means to study the degradation of DNA in thyroid follicular epithelial cells.
Sujets)
Adulte , Femelle , Humains , Mâle , Adulte d'âge moyen , Jeune adulte , Cadavre , Noyau de la cellule/métabolisme , ADN/métabolisme , Épithélium/métabolisme , Anatomopathologie légale , Traitement d'image par ordinateur/méthodes , Modifications postmortem , Magenta I , Coloration et marquage/méthodes , Glande thyroide/métabolisme , Facteurs tempsRésumé
OBJECTIVE@#To establish an anaphylactic shock model induced by human mixed serum in guinea pigs.@*METHODS@#Eighteen guinea pigs were divided into two groups: sensitized and control, The sensitized group were immunized intracutaneously with human mixed serum and then induced by endocardiac injection after 3 weeks.@*RESULTS@#Symptoms of anaphylactic shock appeared in the sensitized group. The level of serum IgE were increased in the sensitized group significantly.@*CONCLUSIONS@#An animal model of anaphylactic shock wer established successfully. It provide a tool for both forensic study and anaphylactic shock therapy.