腐败尸体死亡时间推断1例

1 案例资料 2006年9月9日，辖区内某村在收玉米时距村公路（东西方向）10m远玉米地里发现1具无名尸体，几近白骨化。尸体头南脚北仰卧于玉米行（南北方向）之间，尸旁土地上有散在蛹壳，部分破碎。尸体颈部系着一短袖T恤衫和无带乳罩，下身穿短裙，内裤位于脚踝处，皮凉鞋位于双足处。衣服洗净后颜色可辨，完整无损。尸体头、颈、胸、骨盆、双上肢及大部分脊柱均已白骨化，仅背部、左下肢少量软组织、肌腱、软骨残存，全身骨骼（含舌骨）均无缺失和损伤。     

利用昆虫推断腐败尸体的死亡时间

1　案例资料1999年 4月 2 7日 ,在某山边斜坡小树林丛中 ,发现用蛇皮袋包装的一具男尸 ,经侦查 ,死者叫高某 ,男 ,78岁 ,籍贯江苏 ,拾荒者。被他人杀害再将其口鼻部堵塞上毛巾后 ,装入蛇皮袋内抛尸于发现地。打开包装袋 ,见尸体蜷缩在蛇皮袋内 ,尸体完整 ,全身呈腐败剥脱状 ,尸体上发现有许多大小不等的蝇蛆和飞舞的成蝇 ,尸体周围见有少量红褐色的蝇蛹。法医当即分别提取了成蝇、蝇蛆和蛹 ,送浙大昆虫实验室分别进行种类鉴定 ,同时 ,向当地气象部门了解半月来的温度预报情况 (10～ 2 0摄氏度 )。经过鉴定 ,发现昆虫的种类为大头金蝇。结合…     

借助昆虫学分析推断高原地区尸体的死亡时间

1 案 情 　　某年 8月 10日，西南部高原地区某县国际边界处发现两具无名男尸。现场位于中尼边界 20界桩距向北方向 10km处的高 50m沟壑里，周围长有野草、草长 28cm，未发现踩踏迹象和血迹、两具尸体呈对脚状，脚间距离为 45cm，两具尸体分别编为 1号、 2号。 2 尸体检验 　　1号尸体姿势呈右侧卧，两腿屈曲，尸体身长 168cm，黑发，发长 7cm。上身着一件灰白色夹克衣、衣领处浸污血迹，上衣前胸部有六处刺破口大小不一，最大为 3cm× 0.3cm、最小为 1.5cm× 0.3cm， 一件红白蓝相间花毛衣右前胸上方有一 2.6cm× 0.3cm刺破口。内穿一件白…     

根据C_3转化率和尸体肛温推断死亡时间

本文观察了不同温度条件下,人血中C_3转化率的变化情况。在14个尸解案例中,根据C_3转化率和尸体肛温推断死亡时间,其95％可信区间为±11小时。测定C_3转化率的同时,还可以观察C_3的表型,为无名尸体的个人识别提供依据。     

运用腐败程度评分推断死亡时间的研究现状

腐败程度评分可用于死亡时间推断,具有简便实用,快速准确的优势,适用于基层实践.目前国内对该方法的研究相对较少,不能满足实践需要.本文总结了腐败程度评分方法的应用范围及影响因素,重点介绍了腐败程度评分系统、累积温度天数、回归模型的相关研究现状,希望为死亡时间推断的研究及实践工作提供参考.     

两具水泥掩埋尸体死亡时间推断

1案例1.1简要案情某年10月18日,某拆迁队用打桩机拆迁时发现1个颅骨,遂报案。1.2现场勘验现场位于一临街店铺的隔间内,见一座水泥石墩(高1.0m,长2.0m,宽1.0m),部分已被拆迁破坏。后用锤子敲砸石墩,发现石墩内有两具白骨化尸体(骨骼基本沿生理解剖位置摆放)及衣着物品,尸体之间砌有石砖相隔,将石墩隔离成宽0.7m和0.3m两个隔间(图1,分别对应1、2号尸体)。     

利用尸冷推测死亡时间

在命案现场的现场勘察和尸体检验中 ,常规的尸体检验中对尸体现象如尸斑、尸僵、尸体痉挛和尸表损伤等比较注重 ,这对分析死亡过程、推断死亡时间有一定的作用 ,特别是早期的尸体现象对推测死亡时间可以精确到小时以内 ,这对犯罪嫌疑人的认定和排除有重要意义 ,也是命案现场要解决的最重要的问题之一。死亡时间的推断如何做到精确 ,是全世界法医界尚未解决的重要问题之一 ,只有具备了十分丰富的经验 ,联合运用多种方法综合判断才能达到比较准确的结果。尸冷是早期尸体现象之一 ,正常机体产热与散热保持平衡状态 ,使人的体温恒定在 37℃左右 …     

根据食尸性蝇类推断死亡时间的研究进展

法医昆虫学是应用昆虫学知识解决法医实践中所遇到的相关问题的一门科学。食尸性蝇类在尸体的腐败分解中发挥着重要的作用,运用食尸性蝇类的特点可以更准确进行死亡时间推断,为侦查破案提供线索。本文对依据食尸性蝇类推断死亡时间的方法进行综述,以期为后续的研究与实践应用参考和借鉴。     

利用玉米生长期推断死亡时间1例

利用植物的生长规律推断死亡时间曾有报道，笔者在勘验一起命案时，根据玉米棒的成熟度、玉米的生存环境及尸体的变化规律成功地推断了死亡时间。     

应用嗜尸性昆虫推断死亡时间11例

目的 检验嗜尸性昆虫推断死亡时间的可行性及准确度,为鉴定实践提供参考.方法 筛选11例已破案证实且昆虫学证据比较完整的案件,对案件中出现的昆虫种类、推断结果及真实结果进行统计和对比分析.结果 案发现场所发现的昆虫包括大头金蝇、绯颜裸金蝇、乌足锡蝇、丝光绿蝇、厚环黑蝇、厩腐蝇、麻蝇(未鉴定具体种类)、蛆症异蚤蝇、黑水虻、...     

Brain Fluid Content Related to Body Position and Postmortem Interval – An Animal Model

Adult male Sprague Dawley rats were euthanized and placed in a horizontal or vertical (head‐down) position at room temperature, after which brain fluid content was measured by a moisture analysis technique at variable time points. No significant difference in brain fluid content was observed between horizontal and vertical postmortem positions. A significant increase in brain fluid content was demonstrated 3, 6, and 24 h after death, with maximal fluid content observed at 24 h. Specifically, the brain fluid content of control animals was 77.79 ± 0.36%, increasing to 80.05 ± 0.22% at 24 h (p < 0.0001). This study has demonstrated no significant differences in brain fluid content related to postmortem position, suggesting that a head‐down position is not associated with increased brain fluid content or swelling. However, significant temporal increases in brain fluid content after death, most likely related to cerebral liquefaction, occur.     

256例命案尸体死亡时间推断的回顾性分析

目的探讨降低死亡时间推断误差的方法。方法收集常州市和南京市2003年1月一2013年1月256例已破命案．采用传统方法进行死亡时间推断,与破案后获得的实际死亡时间进行比较,并根据死亡时间进行分组,计算死亡时间推断准确率,分析判断错误原因。结果早期尸体死亡时间（≤12h和13～24h）推断准确率分别为90％、89％,晚期尸体死亡时间（1—7d、1～2周、3～4周、1～6个月、7～12个月和1～5年）的推断准确率随时间的延长下降,分别为79％、76％、83％、79％、60％和50％。推断方法不当、水中尸体、极端温度、客观依据不足、抛尸以及变动或破坏现场是影响死亡时间推断准确率的常见因素。结论综合参考多项指标可降低死亡时间推断的误差。     

The Role of Vitreous Magnesium Quantification in Estimating the Postmortem Interval

The use of magnesium as a parameter to estimate the time of death is controversial. In 32 traumatic deaths with known postmortem intervals (PMIs), small quantities of vitreous humor (VH) were sampled repetitively every 3 h until 24 h postmortem. The bodies were kept at the constant ambient temperature of 20°C (68°F). The concentrations of magnesium were in the range of 0.47–1.15 mM. A statistically significant correlation of the concentration of magnesium with the PMI was observed (r = 0.453, p < 0.01), but with small predictive value—coefficient of variation for regression was 45.5%; the average of the paired differences between the estimated and actual PMIs was 5.24 + 3.19 h. Although useful results might be expected due to the large transmembrane gradient for magnesium, the results of this study strongly disprove the usefulness of measuring magnesium in VH to estimate the time of death.     

Bioelectrical Impedance as a Technique for Estimating Postmortem Interval,,

Estimation of postmortem interval (PMI) is a critical component of death investigation. A cadaver can be hypothesized to be a resistor–capacitor (RC) circuit the impedance (Z) of which changes in a quantifiable manner as the cadaver decomposes. This hypothesis was tested using bioelectrical impedance analysis (BIA) equipment to apply a current with a fixed amplitude at a single frequency to four cadavers over time and measuring two components of Z, resistance (R) and reactance (X_c). Quadratic regression analysis between Z and accumulated degree days (ADD) showed a statistically significant parabolic relationship. The parabolic relationship poses an initial challenge to the use of the method, and additional research is needed to address this issue. However, the results of the reported research support the hypothesis that Z measured using BIA has a relationship to PMI.     

A Study on the Estimation of Postmortem Interval Based on Environmental Temperature and Concentrations of Substance in Vitreous Humor

A method to determine postmortem interval (PMI) based on environmental temperature and the concentrations of vitreous humor (VH) molecules were explored. Rabbit carcasses were placed in a chamber at 5, 15, 25, or 35°C, and 80–100 μL of VH was collected with the double‐eye alternating micro‐sampling method every 12 h. A Roche DPPI biochemical analyzer was used to measure the concentrations of six substances in VH samples. The interpolation function model and mixed‐effect model were employed for data fitting to establish equations for PMI estimation. The concentrations of K⁺, P, Mg²⁺, creatinine (CRE), and urea nitrogen (UN) exhibited an upward trend with increasing PMI in all temperature groups, while the concentration of Ca²⁺ showed a downward trend. Validation results using K⁺ and Mg²⁺ ions revealed that the mixed‐effect model provided a better estimation than the interpolation function model using the data from our experiment. However, both models were able to estimate PMI using temperature and VH molecule concentrations.     

The Impact of Gender,Age and Tissues in vitro on Estimating Postmortem Interval by FTIR Spectroscopy

To investigate the influence of such individual factors as gender,age and tissues in vitro to the postmortem interval(PMI) by the Fourier transform infrared(FTIR) spectrometer in animal experiments.SD rats were classified into male and female groups,different age groups(21-day,42-day and 63-day group),and tissues in vitro and in vivo groups.The rats were sacrificed by cervical dislocation,whose bodies were kept in a controlled environmental chamber set at(20±2) ℃ and 50% humidity.The liver,kidney,spleen,myocardium,brain,lung and skeletal muscle tissues were collected for measurement from time zero to 48 h postmortem.With the change of PMI,no obvious changes were found in the main FTIR absorbance peaks and their ratios at different time points.All the experimental groups showed no significant changes when compared with the controls.The gender,age and tissues in vitro were not found to be contributing factors in the estimation of PMI via FTIR spectroscopy.     

Potential Use of Bacterial Community Succession in Decaying Human Bone for Estimating Postmortem Interval,,

Bacteria are taphonomic agents of human decomposition, potentially useful for estimating postmortem interval (PMI) in late‐stage decomposition. Bone samples from 12 individuals and three soil samples were analyzed to assess the effects of decomposition and advancing time on bacterial communities. Results indicated that partially skeletonized remains maintained a presence of bacteria associated with the human gut, whereas bacterial composition of dry skeletal remains maintained a community profile similar to soil communities. Variation in the UniFrac distances was significantly greater between groups than within groups (p < 0.001) for the unweighted metric and not the weighted metric. The members of the bacterial communities were more similar within than between decomposition stages. The oligotrophic environment of bone relative to soft tissue and the physical protection of organic substrates may preclude bacterial blooms during the first years of skeletonization. Therefore, community membership (unweighted) may be better for estimating PMI from skeletonized remains than community structure (weighted).     

早期死亡时间推断研究进展

死亡时间推断在判断案件的性质、划定侦查范围及锁定嫌疑人等方面至关重要,一直是法医病理学工作的重点和难点。早期死亡时间,即指死后24 h以内,由于距离案发时间更短,对其准确推断能促进案件的成功侦破,具有重要的法医学意义。近年来,国内外法医学者运用一系列新方法和新技术对早期死亡时间推断进行了大量研究。本文对体液生物化学、超生反应、代谢组学、影像学、遗传物质降解规律等方面的研究进展进行综述,以期为早期死亡时间推断的研究和应用提供新的思路。     

大鼠死后骨骼肌FTIR光谱变化与死亡时间的关系

目的应用傅立叶变换红外光谱(FTIR)分析大鼠死后骨骼肌随死亡时间推移的化学降解过程,为死亡时间推断提供新的研究方法。方法大鼠断颈处死后置于(20±2)℃环境,不同的死亡时间点提取大鼠大腿骨骼肌组织,并运用FTIR光谱仪测定不同化学基团随死亡时间的变化。结果随着死亡时间的推移,大鼠骨骼肌组织不同吸收峰的峰强随着死亡时间增加呈现出四种不同的变化方式:增加、下降、稳定、波动,且不同峰强比显示了相似的时间变化趋势。结论FTIR光谱分析技术有望成为法医实践中推断死亡时间的新方法。     

Estimating Time Since Death from Postmortem Human Gut Microbial Communities

Postmortem succession of human‐associated microbial communities (“human microbiome”) has been suggested as a possible method for estimating postmortem interval (PMI) for forensic analyses. Here we evaluate human gut bacterial populations to determine quantifiable, time‐dependent changes postmortem. Gut microflora were repeatedly sampled from the proximal large intestine of 12 deceased human individuals as they decayed under environmental conditions. Three intestinal bacterial genera were quantified by quantitative PCR (qPCR) using group‐specific primers targeting 16S rRNA genes. Bacteroides and Lactobacillus relative abundances declined exponentially with increasing PMI at rates of N_t = 0.977e^?0.0144t (r² = 0.537, p < 0.001) and N_t = 0.019e^?0.0087t (r² = 0.396, p < 0.001), respectively, where N_t is relative abundance at time (t) in cumulative degree hours. Bifidobacterium relative abundances did not change significantly: N_t = 0.003e^?0.002t (r² = 0.033, p = 0.284). Therefore, Bacteroides and Lactobacillus abundances could be used as quantitative indicators of PMI.