法医学杂志 ›› 2020, Vol. 36 ›› Issue (2): 187-191.DOI: 10.12116/j.issn.1004-5619.2020.02.008

• 论著 • 上一篇    下一篇

大鼠死后皮肤傅里叶变换红外光谱变化与死亡时间的关系

黄娇1, 周圆圆2, 邓恺飞3, 罗仪文3, 孙其然3, 李周儒1, 黄平3, 张吉3, 蔡红星1   

  1. 1. 徐州医科大学法医学教研室,江苏 徐州 221004; 2. 内蒙古医科大学法医学教研室,内蒙古 呼和浩特 010030; 3. 司法鉴定科学研究院 上海市法医学重点实验室 司法部司法鉴定重点实验室 上海市司法鉴定专业技术服务平台,上海 200063
  • 发布日期:2020-04-25 出版日期:2020-04-28
  • 通讯作者: 蔡红星,男,教授,硕士研究生导师,主要从事法医学基础及应用研究;E-mail:yccaihx1962@126.com 张吉,男,博士,主检法医师,助理研究员,主要从事法医病理学研究;E-mail:zhangj@ssfjd.cn
  • 作者简介:黄娇(1993—),女,硕士研究生,主要从事法医病理学研究;E-mail:301700111062@stu.xzhmu.edu.cn
  • 基金资助:
    国家自然科学基金资助项目(81801873,81722027,81671869);“十三五”国家重点研发计划资助项目(2016YFC0800702);上海市法医学重点实验室资助项目(17DZ2273200);上海市司法鉴定专业技术服务平台资助项目(19DZ2292700)

Relationship between Postmortem Interval and FTIR Spectroscopy Changes of the Rat Skin

HUANG Jiao1, ZHOU Yuan-yuan2, DENG Kai-fei3, LUO Yi-wen3, SUN Qi-ran3, LI Zhou-ru1, HUANG Ping3, ZHANG Ji3, CAI Hong-xing1   

  1. 1. Department of Forensic Medicine, Xuzhou Medical University, Xuzhou 221004, Jiangsu Province, China; 2. Department of Forensic Medicine, Inner Mongolia Medical University, Hohhot 010030, China; 3. Shanghai Key Laboratory of Forensic Medicine, Key Laboratory of Forensic Science, Ministry of Justice, Shanghai Forensic Service Platform, Academy of Forensic Science, Shanghai 200063, China
  • Online:2020-04-25 Published:2020-04-28

摘要: 目的 运用傅里叶变换红外(Fourier transform infrared,FTIR)光谱技术分析大鼠死后15 d内背部皮肤的光谱变化,以此推断死亡时间。 方法 大鼠麻醉后颈椎脱臼处死,置于温度为25 ℃、湿度为50%的环境中,分别于不同时间点提取其背部皮肤,收集红外光谱数据,并利用机器学习技术对数据进行分析。 结果 大鼠死后背部皮肤组织光谱吸收峰的峰位未发生明显改变,其强度随死亡时间延长而发生变化;偏最小二乘(partial least squares,PLS)回归构建的死亡时间推断模型决定系数(R2)为0.92,预测均方根误差为1.30 d。根据模型中的变量投影重要性(variable importance for projection,VIP)指标确定推断死亡时间的贡献波段为1 760~1 700 cm-1、1 660~1 640 cm-1、1 580~1 540 cm-1和1 460~1 420 cm-1。 结论 应用FTIR技术检测大鼠死后皮肤组织的光谱学改变,为死亡时间推断提供了一种新的思路。

关键词: 法医病理学;谱学, 傅里叶变换红外;机器学习;死亡时间;皮肤;大鼠

Abstract: Objective To infer postmortem interval (PMI) based on spectral changes of the dorsal skin of rats within 15 days postmortem using Fourier transform infrared (FTIR) spectroscopy. Methods The rats were sacrificed by cervical dislocation after anesthesia, and then placed at 25 ℃ and relative humidity of 50%. The FTIR spectral data collected from the dorsal skin at PMI points were modeled with machine learning technique. Results There was no significant difference of absorption peak location among all the PMI groups but their peak intensities changed as a function of PMIs. The model for PMI estimation was constructed using partial least squares (PLS) regression, reaching a R2 of 0.92 and a root mean square error (RMSE) of 1.30 d. As shown in variable importance for projection (VIP), four spectral bands including 1 760-1 700 cm-1, 1 660-1 640 cm-1, 1 580-1 540 cm-1 and 1 460-1 420 cm-1 were determined as important contributions to model prediction. Conclusion Application of the FTIR technique to detect postmortem spectral changes of the rat skin provides a novel proposal for PMI estimation.

Key words: forensic pathology, spectroscopy, Fourier transform infrared, machine learning, postmortem interval, skin, rats