人脾脏细胞核DNA含量与死亡时间关系的图像分析

目的研究人脾脏细胞DNA含量改变与死亡时间的关系。方法选取36例已知死亡时间的人体脾脏,在死后5～36h内逐时进行细胞学涂片、Feulgen Vans染色观察,并用图像分析系统,测定脾脏细胞核积分光密度、平均灰度等灰度参数,所得数据用SPSS软件分析。结果在5～36h内平均光密度、积分光密度、平均灰度均值均与死亡时间显著性相关,并得出对应的回归方程,其中平均光密度、积分光密度随死亡时间的延长而逐渐减小、平均灰度逐渐增大。结论人脾脏细胞核DNA含量改变呈现一定规律,与死亡时间明显相关。

Study on relationship between changes of DNA content in human spleen nuclei and the postmortem interval by image analysis

Objective To study changes of DNA content in human spleen nuclei and seek an experimental method for estimation of the postmortem interval(PMI)using computerized image-analysis technique(CIAT).Methods Smear sections from spleen sampled were collected in 36 cadavers with known the accurate PMI respectively every hour within the first 36 hours after death,which were then fixed with cold Carony fixation.The smeared sections were stained by Feulgen-van's staining method.3 indices for spleen nucleic DNA including integral optical density(IOD),average optical density(AOD)and average gray(AG)were measured using the CIAT.Results IOD and AOD in the spleen nuclei declined regularly,whereas AG increased with the extension of PMIs in 36 hours.Conclusion There are definite relationships between the PMI and gray parameters(IOD、AOD and AG)representing the DAN content of nucleic DNA in the spleen in 36 hours after death,which may be used for estimation of PMI.