Yu Kai, Wang Gongji, Cai Wumin, Wu Di, Wei Xin, Zhang Kai, Liu Ruina, Sun Qinru, Wang Zhenyuan
Department of Forensic Pathology, College of Forensic Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Department of Forensic Pathology, College of Forensic Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, China.
Spectrochim Acta A Mol Biomol Spectrosc. 2020 Oct 5;239:118535. doi: 10.1016/j.saa.2020.118535. Epub 2020 May 26.
The identification of antemortem, perimortem and postmortem fractures is very important for forensic pathologists and anthropologists. However, traditional methods are subjective, time-consuming, and have low accuracy, which do not fundamentally solve the problem. In this study, we utilized Fourier transform infrared (FTIR) spectroscopy and chemometrics to identify antemortem, perimortem and postmortem fractures in a rabbit tibial fracture model. Based on the results of the principal component analysis (PCA), changes in the ante-perimortem fracture repair process are mainly associated with protein variations, while postmortem fractures are more likely to result in lipid changes during degradation. Then, a partial least squares discriminant analysis (PLS-DA) was performed to assess the classification ability of the training and predictive datasets, with classification accuracies of 88.9% and 86.7%, respectively. According to the latent variable 1 (LV1) loading plot, amide I and amide II (proteins) are mostly classified as ante-perimortem and postmortem fractures. In conclusion, FTIR spectroscopy is a reliable tool to identify antemortem, perimortem and postmortem fractures. FTIR has the advantages of rapid, objective and strong discrimination. and shows great potential for analyzing forensic cases under actual natural conditions.
生前、濒死期和死后骨折的鉴别对于法医病理学家和人类学家而言非常重要。然而，传统方法主观、耗时且准确性低，无法从根本上解决问题。在本研究中，我们利用傅里叶变换红外（FTIR）光谱和化学计量学方法，在兔胫骨骨折模型中鉴别生前、濒死期和死后骨折。基于主成分分析（PCA）结果，生前至濒死期骨折修复过程中的变化主要与蛋白质变化相关，而死后骨折在降解过程中更易导致脂质变化。然后，进行了偏最小二乘判别分析（PLS-DA）以评估训练集和预测数据集的分类能力，分类准确率分别为88.9%和86.7%。根据潜变量1（LV1）载荷图，酰胺I和酰胺II（蛋白质）大多被归类为生前和死后骨折。总之，FTIR光谱是鉴别生前、濒死期和死后骨折的可靠工具。FTIR具有快速、客观和鉴别力强的优点，在实际自然条件下分析法医案件方面显示出巨大潜力。
