The Erratic Behavior of Lesions in Burnt Bone

This study analyses depressed fractures (by blunt force trauma) and circular full‐thickness injuries (drill injuries and gunshot wounds) in charred bones. Fifty bovine ribs (total 104 lesions) were divided into three groups. The first group consisted in 20 depressed hammer‐produced fractures; in the second one, 60 round drill‐holes were produced (30 circular, 30 semicircular); in the third group, 12 fleshed and 12 skeletonized ribs were hit by 9‐mm bullets. Each specimen was carbonized in an electric oven up to 800°C. Morphological and metric analyses were performed before and after: morphological features were preserved, but depressed fractures showed an increase in their dimensions (p‐value < 0.05); the drilled holes shrunk (p‐value < 0.01); the charring cycle increased the number of fractures in samples with gunshot wounds differently in fleshed and defleshed ribs. This study showed the complex behavior of charred bone, for what concerns the interpretation of trauma and how caution should be applied.     

铁在自由基介导的脑水肿中的作用

利用冷冻制成家兔局灶性脑损伤，术后２、８、１２及２４小时处死动物。测定脑组织中铁、水、脂质过氧化物（ＬＰＯ）及超氧化物歧化酶（ＳＯＤ）水平．结果表明，术后脑组织中铁、水及ＬＰＯ含量均显著升高（Ｐ＜０．０１），而ＳＯＤ活性则显著下降（Ｐ＜０．０１）。且铁含量的升高与水含量及ＬＰＯ含量的升高有着显著的相关关系。说明铁在自由基介导的脑脂质过氧化及脑水肿的发生发展中起着重要作用。     

核因子-кB及其在创伤性脑损伤后的作用

核因子-кB是一种具有多向性调节作用的核转录因子。机体受到创伤后,NF-кB被激活,调节多种炎性介质基因转录,引起局部及全身的炎症反应。对NF-кB的有关研究可望用于法医学家对损伤时间的推测。     

脑外伤所致精神障碍与道路交通事故伤残评定

目的　探索道路交通事故伤残评定中脑外伤所致精神障碍的临床症状特点、影响因素及鉴定中应注意的问题。　方法　回溯即往一年半的鉴定资料 ,根据CCMD -3器质性精神障碍的症状分类对被鉴定人临床表现进行整理归纳 ,整理被鉴定人颅脑受伤的类型 ,统计分析评定时机及评定结论。　结果　 65例样本纳入本研究 ,平均评定时机10 .2 3± 7.2个月 ,临床主要表现为智能和记忆损害 ,人格改变和神经症样综合征占有较大的比例 ,精神病性障碍和情感障碍较少 ,未见意识障碍和癔症样障碍 ,Logistic回归分析显示智能损害的严重程度及精神病性障碍与伤残等级负相关。　结论　智能和记忆障碍在脑外伤所致精神障碍的道路交通事故伤残评定中具有重要的地位 ,一般应在伤后六个月才宜进行伤残评定。     

实验性脑死亡脑外器官变化

研究了原发性脑死亡垂体、肾上腺、胰腺、脾脏等脏器宏观、微观及超微结构的变化规律．结果如下：（1）胰腺腺泡酶原颗粒减少，胰岛细胞核固缩；（2）脾脏被膜下出血，脾窦扩张淤血；（3）肾上腺皮质及髓质细胞疏松，胞核浓缩；超微结构可见束状带细胞线粒体嵴消失，核质溶解；（4）腺垂体细胞核变小，胞质出现空泡，神经垂体胶质细胞增生，纤维组织排列紊乱，染色浅淡；（5）原发性脑死亡可以引起脑外器官包括垂体、肾上腺、胰腺、脾脏的形态结构变化，但远比脑组织本身的变化轻．     

大鼠液压冲击脑损伤bFGF及其受体FGFR1 mRNA表达

目的 观察脑损伤后 bFGF及其受体 FGFRl mRNA表达及其时序性变化,探讨脑损伤的分子机制及法医学脑损伤时间推断。方法 用原位杂交(ISH)和RT-PCR技术观察大鼠液压冲击脑损伤后bFGF及FGFRl mRNA在伤后不同时间(30min、1h、3h、6h、12h、1d、3d、7d)的表达情况,以正常大鼠及手术大鼠作为对照。结果(1)正常及手术对照组大鼠脑组织内有低水平的bFGF及FGFRl mRNA表达;(2)脑损伤后6h～3d,大脑皮质和脑干bFGF/FGFRl mRNA水平逐渐增加,7d时已有所下降,但仍未恢复到基础水平;(3)海马冲击后3h即开始显著增加,3d开始下降,7d时已恢复到基础水平。结论 脑损伤可诱导bFGF/FGFRl基因表达,机体对脑损伤存在自身保护机制,其表达的时序性改变可望用于法医学脑损伤时间推断。     

大鼠脑挫伤后巢蛋白表达与脑挫伤经过时间的关系

目的观察大鼠脑挫伤后不同时间内巢蛋白(nestin)蛋白表达的变化,探讨其与脑损伤经过时间的关系。方法利用自由落体撞击大鼠脑挫伤模型,在脑挫伤后不同时间(0.5,6,12h和1,3,7,14,28d)观察nestin蛋白在伤侧皮质、海马齿状回及胼胝体表达情况。结果伤后0.5h伤侧皮质、海马齿状回及胼胝体nestin阳性细胞表达开始增强,7d达高峰,以后逐渐下降,28d伤侧皮质、海马齿状回恢复至正常组水平,伤侧胼胝体在伤后28d仍有弱表达。结论nestin免疫组化染色可以作为法医学推断早期脑损伤时间的指标之一;nestin可作为判断脑损伤是否存在及区分生前和死后脑损伤的标志。     

人脑挫伤后细胞周期素D1表达的变化

目的研究CyclinD1在人不同部位脑挫伤组织中表达的变化及其与损伤时间的关系。方法88例脑挫伤标本按损伤后存活时间0.5,1,3,24h和3,7,14,30d分为8个实验组,另以6例非脑挫伤的脑作为对照组,应用CyclinD1免疫组织化学并结合图像分析技术观察CyclinD1的变化。结果脑挫伤后,挫伤灶中央CyclinD1阳性细胞几乎丧失,1h后挫伤灶周围CyclinD1阳性细胞开始增加,3h～30d之间各组挫伤灶周围免疫阳性反应的细胞增加显著,在3h～30d一直维持在较高水平;CyclinD1主要见于小胶质细胞和其它胶质细胞,少数神经元也呈阳性。结论人脑挫伤后,CyclinD1在多种脑细胞内表达,以胶质细胞表达明显,CyclinD1阳性细胞在伤后不久即显著增加,故可作为早期脑损伤的诊断指标。     

Blunt force cranial trauma in the Cambodian killing fields

In this paper we present a unique pattern of blunt force cranial trauma that was observed in 10 of a sample of 85 crania from a Cambodian skeletal collection comprised of Khmer Rouge victims. Initial examination of the trauma, which presents as substantial damage to the occipital with fractures extending to the cranial base, suggested the pattern was classifiable as a basilar or ring fracture. However, further investigation, including trauma analysis and historical research, revealed that this fracture type is distinctive from basilar and ring fractures. Historical data indicate that a particular execution method was the likely source of the trauma. Recognition of this trauma pattern is significant because it exemplifies the distinct fracture configuration resulting from an apparently categorical and methodical execution technique. Identification of this fracture type could potentially assist forensic investigators in the recognition of specific methods of murder or execution.     

Macroscopic and microscopic analysis of knife stab wounds on fleshed and clothed ribs

Stab wounds upon bone are analyzed to interpret the weapon used and the physical context in which the attack occurred. The literature demonstrates that most research conducted pertaining to wound patterns has been carried out on defleshed and unclothed bone samples, not adequately replicating actual circumstances. For this research, six half pig torsos (Sus scrofa), fleshed (including muscle, fat, epidermis, and dermis layers) and clothed, were stabbed using three knife types, applying both straight and downward thrusts. Analysis conducted macroscopically and through a scanning electron microscope with an environmental secondary electron detector revealed a general lack of consistency in wound pattern and associated secondary effects. Consequently, it was not possible to establish wound pattern per knife type as suggested in previous research or relate it to stab motion. Advantage of microscopic analysis was evident in recognizing wound traits and observation of trace evidence not visible macroscopically.