Investigating the Postmortem Molecular Biology of Cartilage and its Potential Forensic Applications

This study investigated the postmortem molecular changes that articular cartilage undergoes following burial. Fresh pig trotters were interred in 30‐cm‐deep graves at two distinct locations exhibiting dissimilar soil environments for up to 42 days. Extracts of the metacarpophalangeal (MCP) and metatarsophalangeal (MTP) joint cartilage from trotters disinterred weekly over 6 weeks were analyzed by Western blot against the monoclonal antibody 2‐B‐6 to assess aggrecan degradation. In both soil conditions, aggrecan degradation by‐products of decreasing molecular size and complexity were observed up to 21 days postmortem. Degradation products were undetected after this time and coincided with MCP/MTP joint exposure to the soil environment. These results show that cartilage proteoglycans undergo an ordered molecular breakdown, the analysis of which may have forensic applications. This model may prove useful for use as a human model and for forensic investigations concerning crimes against animals and the mortality of endangered species.     

肋软骨刺创的实验研究

本文对不同厚度的单刃刺器在肋软骨上形成的刺创口进行了肉眼和实体显微镜下的形态学观察，发现肋软骨上的刺创口与皮肤和骨质上的刺创口有着明显的不同。观察结果表明，创口的宽度不能反映刺器的厚度。一定厚度的单刃刺器所致的肋软骨上的创口肉眼及镜下无明显的钝角特征。据此，对在肋软骨上刺器所致刺创的凶器种类的推断提出新的见解。     

蛋白酶K-Chelex100法提取肋软骨DNA技术的优化

目的优化蛋白酶K的用量和消化时间,用于提取肋软骨DNA。方法 30份肋软骨样本各取大小为0.2cm×0.3cm×0.4cm的软骨块5份,分别编为A～E组。采用不同蛋白酶K用量和消化时间的Chelex100方法,提取5组各30份软骨块DNA,进行DNA定量、采用Sinofiler试剂盒扩增后进行电泳检测,采用非参数检验法比较检验成功率。结果 A～E组样本中采用加入2μL蛋白酶K并消化30min的D组方法成功率最高(96.7%),组间差异具有统计学意义。结论采用蛋白酶K-Chelex100方法,选择加入2μL蛋白酶K,消化30min可有效提高肋软骨DNA分型检验成功率。     

肋软骨分析检验技术在法医学中的应用

传统法医人类学对肋软骨的分析检验仅限于形态学检验.近年来,法医影像学以及分子遗传学的发展丰富了人类肋软骨的分析检验技术,并且已经能够运用于法医学实践中.本文从肋软骨的组织学特性入手,综述了近年来肋软骨在法医人类学性别判定、年龄推断等方面的研究进展,以期为同行提供借鉴和参考.     

肢体关节功能计算方法的比较

目的分析比较两种不同的关节功能计算方法．探讨关节功能评定方法的合理性。方法收集福建闽中司法鉴定所2007--2010年道路交通事故致四肢大关节损伤伴有或不伴有周围神经损伤案件806例．分别应用关节运动活动度和《法医临床司法鉴定实务》中的方法（查表法）计算关节功能丧失程度,并根据损伤关节和损伤性质对两种不同方法的评残结果列表比较分析。结果单纯性骨关节损伤642例．两种方法评残结果完全一致。骨关节损伤伴有用圉神经损伤118例,若按直接查表法评定均达到伤残程度,且有33例（28．00％）伤残等级比用关节活动度法评残有不同程度的提高,而且按关节运动活动度法有21例（17．80％）未达到伤残程度。结论应用直接查表法计算关节功能丧失程度比单纯应用关节运动活动度替代关节功能作评残依据更简便、更科学、更合理。     

根据中国汉族女性甲状软骨推算年龄的研究

目的 根据中国汉族女性甲状软骨推算年龄。方法 对69例已知年龄的中国汉族女性甲状软骨进行软X线摄片和(或)普通X线摄片,从甲状软骨的摄片上选择5个与年龄变化关系较为密切的观察部位,每个部位又划分成3至6个等级,然后采用多元线性回归分析法,建立其推算年龄的数学模型。结果运用该方法推算女性甲状软骨年龄,其标准差为1.969,复相关系数为0.984。结论 本方法适用于中国汉族女性甲状软骨年龄推算,其有效年龄范围为18～60岁。     

Ossification of laryngeal structures as indicators of age

As the role of forensic anthropologists expands to the medical examiner setting, their expertise is being applied beyond the traditional dry skeletal material. In such scenarios radiographic techniques can be applied when maceration is not appropriate. This study explores the use of radiographic analysis of laryngeal structures for age-at-death determination. Isolated human laryngeal structures (n = 104) from individuals between the ages of 15 and 89 were removed at autopsy and radiographically examined. The cricoid and individual regions of the thyroid cartilage were scored according to degree of ossification, and the relationship between age and degree of ossification statistically examined. A previously published study on age-determination from thyroid ossification by Cerny was assessed for accuracy. The results of the study indicate that although a consistent sequence in the ossification of laryngeal structures exists, variations in timing does not permit narrow age range estimates. Consequently the method presented by Cerny is inaccurate and should not be used in the forensic setting.     

A meta-analytic review of the frequency and patterning of laryngohyoid and cervical fractures in cases of suicide by hanging

The frequency and distribution of fractures are commonly utilized to assist in interpreting the manner of death. In cases of alleged suicide by hanging, however, the evidence base for the frequency and patterning of laryngohyoid and cervical vertebrae fractures resulting from such blunt force traumatic events is limited and so fractures cannot be reliably used to assist in interpreting the manner. Using meta-analytic techniques, this study aimed to estimate frequency and distribution of fractures in the context of relevant intrinsic and extrinsic variables. A systematic review of the literature identified 20 studies with relevant data (8523 cases of suicide by hanging). Meta-analyses identified the frequency and distribution of fractures present and how fracture frequency was affected by the subgroups of age, sex, completeness of suspension, ligature knot position and study design. Results indicated that fracture frequency was variable, there was no unique patterning, and high levels of heterogeneity were present in all variable sub-groups. Age was the only subgroup to show differences. Findings suggest that neck fracture frequency is inconsistent and cannot be predicted by the chosen variables. Subsequently, neck fractures in isolation should not be given weight in medico-legal interpretations of a hanging death as suicidal.     

The Role of Postmortem Computed Tomography in the Evaluation of Strangulation Deaths

We explored the value of postmortem computed tomography (PMCT) to augment autopsy in evaluating strangulation fatalities. A literature search identified 16 studies describing autopsy findings in 576 deaths and two studies describing autopsy and PMCT findings in six deaths. Similar cases were identified from our institution, yielding 130 deaths with autopsy findings and 14 deaths with both autopsy and PMCT findings. The presence of laryngohyoid fracture and soft tissue hemorrhage was compared from autopsy and autopsy+PMCT cases. The detection rates of fractures in autopsy and autopsy+PMCT cases were not significantly different. PMCT identified all fractures observed at autopsy and five fractures not identified. While PMCT may not detect soft tissue injuries in decomposed remains or subtle internal hemorrhages in neck injury, it is equally able to detect bony injuries as autopsy and might surpass autopsy in detecting subtle fractures. We conclude PMCT is useful to supplement autopsy in strangulation cases.     

大鼠死后肋软骨细胞核DNA含量随死亡时间的变化

目的研究大鼠死后肋软骨细胞核DNA含量与晚期死亡时间的相关性。方法应用改良的Feu lgen法结合计算机图像分析技术对死后大鼠35d内肋软骨细胞核DNA含量变化进行观测分析。结果死后1~28d,细胞核染色逐渐变淡,至35d时已观察不到,死后肋软骨细胞核DNA含量与死亡时间呈直线相关。结论大鼠肋软骨细胞核DNA含量随死亡时间延长呈线性规律下降。