DNA降解与腐败尸体死亡时间的相关性

目的探讨骨髓细胞核DNA含量变化与腐败尸体死亡时间的关系。方法应用DNA高度特异性染色方法Feulgen改良法结合计算机图像分析技术对死后不同时间(0～14d)胸骨骨髓细胞核DNA含量变化进行分析。结果胸骨骨髓细胞核DNA含量随死亡时间延长呈缓慢而规律下降,直至死后两周仍未完全降解。结论死后DNA降解速率与死亡时间呈线性关系,测定死后骨髓细胞核DNA含量可望成为腐败尸体死亡时间推断的新方法。     

男性耻骨结构软X线影像与年龄关系的研究

根据118付10～60岁男性耻骨样本的软X线片形态，设计了新的数量化赋值指标标准。用数量化理论Ⅰ和逐步回归数学模型对所得数据进行统计分析，借用电子计算机技术，建立两个推断男性耻骨年龄方程。其方程检验：复相关系数（R）分别为对0．9843和0．9818；标准差（S）分别为：2．52和2．54；两个方程均F＞F0.001；P＞0．01。按新的指标标准赋值，经4个省市提供的58例（其中3例为实际应用案例）未用过的男性耻骨拍摄的软X线影像照片测试；±S8296％，±2S96．56％，其结果达到设计要求。该方程可用来推断男性耻骨年龄。     

耻骨推断年龄方程改进

为了进一步提高耻骨推断年龄方程推广使用价值,在原方程454副样本基础上又增加146副,共600副（男、女各300副）。观测项目（形态特征）由男女各9个减为各8个。有效赋分标准,男性增加5个;女性增加4个。每项中0改为1。使用数量化理论1和逐步回归数学模型,取得8个方程、6个推断年龄表。应用时可根据不同性别、不同年龄组,选用不同推断年龄表,使用不同标准差。比原方程,提高了实际应用价值。     

脑挫裂伤后脑水肿CT表现及其与受伤时间的相关研究

分析120例脑挫裂伤后脑水肿的CT表现及其两者形成时间的关系,提出脑水肿的分级和分型,以Ⅰ-Ⅱ组脑水肿和“O”型脑水肿多见,Ⅰ级脑水肿形成时间平均17小时,Ⅱ级形成时间平均30小时,Ⅲ-Ⅳ级形成时间平均72～73／小时,受伤时间与R值呈正相关（r=0．431）,P＜0．001．回归方程Y=6658＋79．152x,受伤时间与D值也呈正相关（r=0．429）P＜0．001,回归方程Y=39．362－32．335x。并首次指出这时间变化规律可作为脑挫裂伤受伤时间的推断依据。     

钝器致鼻部骨折95例法医学分析

目的探讨钝器致鼻部骨折种类、骨折及其修复的X线与CT表现差异等特点,为鉴定实践提供参考。方法对福建省古田县1999年1月至2013年12月发生的95例成年人因钝器致鼻部骨折的实际案例,按基本情况、骨折部位、致伤方式、确诊方式、鉴定意见等信息进行描述性统计,并对不同损伤根据新旧标准得出的鉴定意见进行比对。结果 95例成年人中,男性87例,女性8例,骨折部位、数量与鼻骨解剖关系、受力大小和方向均有明显的关联,复合性骨折多见,X线检查无法确定的骨折,经CT检查均可明确诊断。不同骨折类型按新旧标准鉴定意见有所不同。结论鼻部骨折数存在性别差异,外力大时易出现复合性骨折,CT检查明显优于X线检查。     

Detection of methamphetamine in mouse femurs exposed to high temperature

Bone samples are valuable for examining the cause of death and circumstance leading up to death when body fluids are not available for forensic toxicological analysis. Examined were heat-induced changes in methamphetamine and amphetamine concentrations in femurs removed from methamphetamine-injected mice to determine if the burned bones could be used for toxicology testing. The femurs were heated at 100°C, 300°C, or 500°C for 10 or 30 min. The tissue structure of the heated femurs was preserved at 100°C for 30 min but was destructed at higher temperatures. Methamphetamine and amphetamine were detected in femurs heated at 100°C for 10 min, 100°C for 30 min, and 300°C for 10 min (with methamphetamine and amphetamine concentrations ranging from 0.36 to 35 μg/g and 0.54 to 47 μg/g, respectively). Methamphetamine and amphetamine were detectable when heated above their decomposition temperature as a result of limited heat transfer do to protection provide by the femoral muscle. Thus, the bone could be a useful analytical sample in cases of burn-related deaths, where it is difficult to collect body fluids.     

致猪水肿病大肠杆菌标准菌株F107/86 fedA基因的克隆与原核表达

以致猪水肿病大肠杆菌标准菌株F107/86的基因组DNA为模板,对去掉信号肽的456bp的fe-dA基因进行了PCR扩增,将其克隆到原核表达载体pGEX-6P-1的BamHⅠ与EcoRⅠ位点之间,经酶切鉴定与测序,在大肠杆菌中以IPTG诱导表达,并对表达产物用SDS-PAGE和Western-blot分析进行验证。结果表明,筛选出的阳性质粒pGEX-fedA-2(pfedA)经测序并与GenBank中收录的M61713序列进行比较,证明插入序列及读码框正确;表达产物GST-FedA经SDS-PAGE分析大小约42.4ku,Western-blot分析证实其具有良好的反应原性。所构建的原核表达载体可大量表达抗原蛋白,为进一步研究猪水肿病亚单位疫苗奠定了基础。     

Use of a Gelatin‐based Consolidant to Preserve Thermally‐Altered Skeletal Remains,

Thermally altered skeletal remains can be very fragile and fragmented and are typically further fragmented or even destroyed when handled; recovery of such remains from a scene can therefore be extremely challenging. There are few recommendations and no generally accepted practices for preserving burned bone for recovery and transport. Here, we test whether the application of a gelatin‐based consolidant at the scene can preserve thermally altered bone in the condition and relative anatomical position in which it was discovered. A solution of Knox^® brand gelatin and water was applied to burned pig mandibles using a spray bottle. Qualitative and quantitative analysis indicates that the application of the consolidant significantly decreased fragmentation as compared to untreated controls (p < 0.05), with most of the treated mandibles remaining completely intact after recovery and transport to a secondary location. In addition to the effectiveness for preservation, the method is also easy to apply, inexpensive, and reversible.     

The Impact of Freezing on Bone Mineral Density: Implications for Forensic Research

It is common for researchers using animal or human remains for scientific study to freeze samples prior to use. However, effects of freezing on bone macro‐ or microstructure are relatively unknown. The research objective of this study was to determine whether freezing could potentially bias experimental results by analyzing changes in bone mineral density (BMD) with the freezing of remains over time. Eight fetal pigs were scanned to determine their initial BMD before freezing. Three piglets underwent a freeze‐thaw cycle to assess the effects of the freezing process. Four piglets were frozen and scanned weekly for 20 weeks to assess freezing over time. The overall average between the fresh initial scan and final frozen scan was significantly different (p < 0.001). Per contra, the final thawed BMD scans did not differ from the initial fresh scan (p = 0.418). Thus, completely thawed remains are recommended for experimental studies.     

Characteristics and Frequency of Chipping Effects in Near‐Contact Gunshot Wounds

The presence of “chipping” or “flaking” around the edges of gunshot entry wounds has been described among the characteristics of gunshot wounds in bone. In this study, the real frequency of such a peculiar feature was investigated. The presence of “chipping” was assessed on 22 gunshot wounds fired at a near‐contact range on bovine ribs with 9‐mm bullets. As controls, five samples were shot with a 3 cm range, and five from 40 cm. In 77% of cases shot at near‐contact range, a detachment of small fragments of the upper layers of bone was detected, mainly with a circumferential disposition, whereas this feature was lacking in control samples. The study demonstrated the frequency of “chipping” and that it may probably be due to a combined ballistic effect of impact of the bullet itself and expansion of gases. It may be thus considered indicative of close‐range shots.