对唾液污染源的鉴定及其基于微生物相对和绝对丰度的TSD推断的探索性研究
Xi Wang1,2, Xi Yuan1, Yifeng Lin1
1Guangzhou Key Laboratory of Forensic Multi-Omics for Precision Identification, School of Forensic Medicine, Southern Medical University, Guangzhou, China.
International journal of legal medicine
|April 16, 2025
概括
法医科学现在可以识别唾液污点,并通过微生物分析估计沉积以来的时间. 这项研究表明,绝对微生物量化对唾液污点的早期时间-自-沉积推断有希望.
科学领域:
- 法医微生物学 法医微生物学
- 分子生物学分子生物学
- 这是下一代测序.
背景情况:
- 对体液污染物的微生物分析是法医科学中日益增长的趋势.
- 很少有研究使用微生物数据将组织源识别与时间自沉积 (TsD) 推断整合在一起.
- 从其他体液区分唾液污点和估计沉积时间是重要的法医任务.
研究的目的:
- 用特定的唾液相关细菌将唾液污点与其他体液和表皮组织区分开来.
- 评估唾液污点中的微生物相对和绝对丰度的时间变化.
- 结合组织来源识别和唾液污点的TSD推断.
主要方法:
- 用了四种丰富的唾液相关细菌进行鉴定.
- 采用定量实时PCR来分析微生物丰富度.
- 对56个唾液样本进行了微生物组成和时间分析.
- 应用贝塔多样性分析和支持向量机 (SVM) 模型用于分类和预测.
主要成果:
- 长达60天的唾液污点保留了足够的细菌标记.
- 许多微生物类和属在相对和绝对丰度方面表现出明显的时间变异模式.
- 绝对微生物量化数据显示,与相对数据相比,随着时间的推移,存在更大的差异.
- SVM模型在不同时间点 (1h,1d,7-60d) 进行唾液污点的分类时实现了>0.8的预测准确性.
结论:
- 该研究成功地结合了唾液污点识别和TSD推断.
- 绝对微生物量化显示了准确的早期TD推断 (14天内) 的潜力.
- 这种方法为法医调查提供了有价值的线索.
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