实时定量PCR检测大鼠脑挫伤后HIF-1α mRNA的表达

目的研究大鼠脑挫伤后挫伤部位脑组织HIF-1α mRNA的表达随损伤时间变化的规律及其在脑损伤时间推断中的应用。方法以Feeney法建立大鼠闭合性脑挫伤模型,应用实时荧光定量PCR技术检测脑挫伤部位HIF-1α mRNA的表达,采用2-△△Ct法比较实验组与对照组脑组织HIF-1α mRNA表达的倍数关系。结果与对照组相比,HIF-1α mRNA的表达在伤后1h即达到高峰,随后下降,伤后24h出现一次较小高峰,3～14d逐渐恢复至对照组水平。结论脑挫伤后HIF-1α mRNA的表达随损伤时间的变化呈现出一定规律性,可作为推断早期脑挫伤经过时间的生物学指标之一。     

大鼠脑挫伤后NF．κBmRNA表达规律的研究

目的应用实时定量PCR技术榆测大鼠脑挫伤后脑组织中NF—κBmRNA的时序性表达规律。方法 Wistar大鼠64只,随机分为1个对照组和7个实验组,每组8只。建立大鼠脑挫伤模型,于伤后0．5h、6h、12h、1d、3d、7d及14d取材,一步法提取总RNA,检测其完整性和浓度,按照0．4“g总RNA量逆转录合成第一链eDNA,以RPL32为参比基因进行荧光定量检测,采用△Ct法比较其与对照组脑组织中NF—κBmRNA表达的倍数关系。结果NF-κBmRNA的表达于脑挫伤后呈现先增高后下降的表达规律,0．5h升高,为对照组的9．190倍,伤后12h升至最高,为对照组的13．40倍,随后开始下降,至伤后14d时仍维持较高水平,为对照组的2．585倍。结论大鼠脑挫伤后脑组织中NF—RBmRNA的表达随着损伤时间呈现先增高后降低的规律性变化,可望作为推断早期脑挫伤的客观指标之一。     

大鼠不同程度脑挫伤后caspase-3表达的研究

目的阐明不同程度及不同时间脑挫伤后caspase-3表达的变化。方法应用免疫组织化学染色、Westernblot和RT-PCR方法对48例实验性脑挫伤大鼠的脑组织进行了检验,同时以3例非脑挫伤和3例假手术的脑组织做对照。结果伤后1hcaspase-3即有表达,24～48h达高峰,挫伤后14dcaspase-3仍维持较高水平。阳性细胞多集中于挫伤区及周围带皮质和脑实质内海马区,不同程度脑挫伤各组之间阳性细胞面积和灰度存在差异;损伤组caspase-3酶原裂解增加,不同程度脑挫伤各组之间存在一定的差异;损伤组cas鄄pase-3表达量明显高于对照组;不同程度脑挫伤组之间于各个时间段caspase-3mRNA表达未见差异。结论Caspase-3表达增加,可辅助诊断1h～14d的脑挫伤,caspase-3阳性细胞面积和灰度的变化及酶原裂解程度与脑挫伤程度有关。     

大鼠肌肉挫伤c—fos的表达

目的研究原癌基因c-fos的表达与肌肉挫伤的关系。方法50只SD大鼠随机的分为实验组和对照组,用免疫组化SP法观察大鼠肌肉挫伤后c-fos蛋白表达。结果随着损伤经过时间的延长,c-fos蛋白表达强度以及阳性面积增加,损伤后15min出现阳性信号,1h达到高峰,1d后恢复正常表达水平。结论原癌基因c-fos表达的检测可作为推断肌肉挫伤时间的指标之一。     

浅析外伤性脑梗塞

通过十四例外伤后脑梗塞案例分析,对外伤与脑梗塞的关系进行阐述,认为外伤性脑梗塞的主要原因是脑动脉血栓形成和栓塞。动脉内膜损伤致血栓形成多在四小时后;颅内出血致血管痉挛造成脑血栓多在1至3周之间;外伤致动脉粥样硬化斑块脱落造成栓塞即刻发生,结合年龄大小、有无心血管疾患以及脑梗塞的部位,便可弄清损伤与脑梗塞的关系。     

外伤性癫痫的法医学鉴定21例分析

为了探讨颅脑损伤后癫痫的法医学鉴定要点,对 21例颅脑损伤后癫痫出现发作者进行了现病史、既往史调查,并结合临床脑电图（ EEG）及 X线片、 CT片、 MRI片等影像学资料。结果发现外伤后癫痫常继发于严重的颅脑损伤,多以晚期发作为主,其发作性质决定于颅脑损伤的部位和程度,头皮 EEG和 24小时动态 EEG证实有异常癫痫样波存在,影像学检查有助于定性分析。结果提示：外伤性癫痫法医学鉴定必须以掌握外伤史及既往史为基础,结合 EEG、 CT、 MRI等检查方可作出正确鉴定。     

定量检测NSE和S-100推断脑挫伤时间的动物实验

观察实验性大鼠脑挫伤后NSE、S－100的时间性变化规律,为法医学推断脑挫伤形成时间提供新的手段。采用改进的Feeney氏落体打击致Wistar大鼠脑挫伤模型,进行免疫组织化学SP法染色,并利用图像分析仪对免疫组化染色阳性细胞灰度和面积进行测量,SAS统计软件分析,结果显示：NSE阳性神经元灰度与面积在伤后1h至2d呈下降趋势,至伤后12h阳性细胞灰度、面积降到最小值（P＜0．01）;S－100阳性细胞面积和灰度伤后呈上升趋势,至伤后4dS－100阳性细胞灰度、面积达到最大值,与对照组及其它实验组比较均有显著性差异（P＜0．01）,伤后5d仍保持较高水平;NSE、S－100免疫组织化学染色阳性细胞的数量、灰度、面积改变有时间规律。推断2d内脑挫伤可用NSE作为主要指标,推断2～5d的脑挫伤则以S－100改变为主。     

Delayed fatal impact cardiopathy

The lesions of impact cardiopathy ("cardiac contusion") which fail to heal satisfactorily, leading to delayed heart failure and death, are infrequently recognized, in part because of a general lack of appreciation of the lingering significance of lesser degrees of trauma. The case of a 31-year-old male dying 4 weeks after a vehicular collision provides strong confirmation of the expectable intermediate aspects of this spectrum of post traumatic lesions.     

Can Neck Contusions in Unexplained Pediatric Deaths be Explained by Cardiopulmonary Resuscitation?

The distribution of cutaneous contusions in infants may raise the possibility of maltreatment. Neck contusions are particularly problematic since they seldom occur outside the setting of abuse, while cardiopulmonary resuscitation (CPR)‐related maneuvers may involve the neck. To address the role of CPR in neck findings, we examined 260 consecutive pediatric autopsies in which CPR was attempted. No neck contusions were identified in manners of death classified as natural, undetermined, or suicide. Contusions were present in two of 80 deaths classified as accident and had obvious accidental causes. About 26% of deaths classified as homicide had neck contusions with no explanation provided by the caregiver (p < 0.0001). In conclusion, neck contusions in deceased children with no apparent explanation should be regarded as suspicious for abuse and investigated accordingly. CPR is not a plausible explanation for neck contusions in children.     

Abrasion Collar Around Shrapnel Entry Wound

Abrasion collar is usually described as a feature of bullet entry wounds caused by friction and indentation. The present case is that of the peculiar entry wound caused by a piece of flying shrapnel which was ejected from a furnace in a steel plant. The scrap metal which exploded in the plant was sourced from the West Asia region. The entry wound on the chest was circular and had an abrasion collar around it. The projectile was a cylindrical object of obscure origin. The forensic science laboratory put forth the possibility that the projectile was a component of an artillery fuze. A decades old study which employed high‐speed photography has rejected the possibility that abrasion collars are produced by friction. High‐velocity projectiles other than bullets can also produce abrasion collars as the rubbing of the bullet against the skin or its rotation are not the causative mechanisms.