硬脑膜厚度及生物力学参数时序性变化在死亡时间推断中的应用

目的研究人尸体硬脑膜厚度以及生物力学参数与死亡时间(postmortem interval,PMI)的关系,探讨其用于推断PMI的可行性。方法收集尸体检验的硬脑膜样本并按死后6h、12h、18h、24h、30h、36h、48h、60h、72h、84h、96h分组,统一制作成4.0cm×1.0cm的A、B两块试件。测量A试件厚度后检测极限载荷、最大力变形、抗拉强度、弹性模量、断裂力等生物力学参数,分别拟合厚度和生物力学参数值与PMI的回归方程,并通过验证组验证PMI预测值与实际值之间的差异。B试件经10%中性甲醛溶液固定后制备组织切片观察其形态学变化。结果死后6~96h,硬脑膜厚度逐渐减小,胶原纤维从排列清晰逐渐变为相互融合,细胞核数量逐渐变少;硬脑膜厚度、极限载荷、抗拉强度、弹性模量、断裂力呈时序性下降趋势,其中硬脑膜厚度、极限载荷、弹性模量、断裂力与PMI具有相关性(P<0.05)。回代检验中验证组PMI实际值和预测值之间差异无统计学意义(P>0.05)。结论人死后6~96 h的硬脑膜厚度、极限载荷、弹性模量、断裂力呈时序性变化,利用其与PMI的关系建立的回归方程可用于PMI推断。     

利用猪胸主动脉生物力学性能时序性变化推断死亡时间

目的观察分析家猪尸体胸主动脉生物力学性状指标的变化规律,探讨其在死亡时间(PMI)推断中的应用价值。方法采集180根家猪的主动脉,在恒定温度、湿度下,于2～230h之间每间隔12h设置1个取检材时间点组;各组主动脉检材用电子万能材料试验机拉伸检测极限载荷、极限载荷变形、平均力、应力、应变,宽度和厚度等生物力学参数指标;应用多元逐步回归方法进行统计学分析。结果家猪死后230h内,随PMI延长,胸主动脉大体观呈自溶腐败性变色、瘫软、液化趋势。生物力学参数指标中,极限载荷、平均力和应力呈随PMI延长呈明显下降趋势,PMI间隔24h组间比较差异性均有统计学意义(P<0.05),校正决定系数分别为0.923、0.806、0.867,估计标准误差分别为±18.39h、±29.88h、±24.58h,PMI间隔24h组间比较差异性均有统计学意义(P<0.05),其它指标与PMI之间相关性不显著均P>0.05。结论死后230h内家猪胸主动脉的极限载荷、平均力和应力的死后时序性变化,与PMI呈明显的负相关性,可用于PMI推断,其中极限载荷效果最佳。     

二维与三维测量在面部软组织厚度研究中的应用

目的 使用不同方法测量面部软组织厚度(FSTT)，为我国北方汉族成年人的颅骨面貌复原提供方法及数据支持。方法 收集123名北方汉族成年人（男性64名，女性59名）的颅面部薄层螺旋CT图像，进行三维重建并初步选取38个颅骨标志点；对所有受试者标志点的软组织厚度进行三维测量，随机选取其中50例进行二维测量；比较两种方法的测量结果是否存在显著差异，分析不同性别、年龄、BMI对面部软组织厚度的影响。结果 配对t检验显示，两种方法测量的数据相关性均> 0.7,30个标志点的差异有统计学意义（P <0.05）；多因素方差分析（MANOVA）显示，有13个和35个标志点分别在不同性别和不同BMI间的差异有统计学意义（P <0.05），仅6个标志点在不同年龄段间的差异有统计学意义（P <0.05）。结论 不同测量方法会影响面部软组织厚度的测量结果，我国北方汉族成年人面部软组织厚度受性别和BMI影响较大，受年龄影响较小。     

大鼠脑挫伤后caspase-3和HAX-1的表达

目的观察大鼠脑挫伤后半胱氨酸天冬氨酸蛋白酶3(caspase-3)和造血干细胞特异性相关结合蛋白-1(HCLS1-associated protein X-1,HAX-1)在损伤后不同时段的表达规律,探索损伤时间推断的新方法。方法建立成年SD雄性大鼠脑挫伤模型,随机分为脑挫伤后2 h、6 h、12 h、1 d、3 d、7 d组,假手术组和正常组。采用Western印迹法检测大鼠脑挫伤后caspase-3和HAX-1的蛋白表达。采用激光共聚焦显微镜检测技术对脑挫伤后HAX-1阳性细胞数和TUNEL染色细胞数进行观察。结果脑挫伤后,随着损伤时间的延长,caspase-3表达逐渐增强,3 d达到峰值,以后逐渐下降,7 d仍高水平表达(P<0.05)。HAX-1阳性细胞表达在伤后开始升高,6 h表达强度最高(P<0.05),12 h后逐渐下降,伤后3 d几乎测不到。TUNEL染色细胞数在伤后2 h明显增加,伤后3 d数量最多,此后逐渐减少,7 d仍维持较高水平(P<0.05)。结论大鼠脑挫伤后caspase-3、HAX-1的表达有时序性变化,可能成为脑损伤时间推断的新依据。     

曲马多依赖大鼠动物模型建立的实验研究

目的建立曲马多依赖大鼠动物模型。方法 30只大鼠平均分为3组,观察以60mg/kg曲马多灌胃给药与停药戒断过程中大鼠的身体依赖和精神依赖表现。结果曲马多依赖组大鼠在给药后15min内,对声音及触摸刺激反应性增高,奔跑、跳跃、竖尾等现象为3.9±0.4次/只,明显高于对照组的0.5±0.1次/只(P<0.05);条件性位置偏爱实验中,曲马多依赖组大鼠明显偏爱给药的白箱(P<0.05)。而戒断组在停止给药后出现烦躁不安、高度激惹、尖叫等行为4.9±0.7次/只,高于依赖组的0.6±0.2次/只(P<0.05);依赖组与戒断组大鼠体重明显下降(P<0.05)。结论以60mg/kg灌胃给药112d,大鼠对曲马多产生依赖,曲马多依赖大鼠动物模型建立成功。     

颅内外骨缝推断年龄的探讨

本文报告16～92岁的140例颅骨的颅内外冠状缝、矢状缝、人字缝的愈合情况。骨缝愈合的主要影响因素为身长、颅外冠状缝右侧第3部(P相似文献   

大鼠急性脑干损伤致死后脑干组织细胞色素C含量的测定

目的探讨细胞色素C含量测定在脑干损伤死后诊断中的意义。方法采用重物自由落体造成的大鼠急性脑干损伤模型,通过酶联免疫(ELISA)的方法,检测脑干损伤致死大鼠与非脑干损伤致死大鼠脑干组织细胞胞浆细胞色素C含量。结果急性脑干损伤组神经元细胞胞浆细胞色素C的含量(8.276±0.425)较非脑干损伤组(2.002±0.514)为高,其差异具有显著性意义(P<0.05)。结论脑干组织细胞色素C含量测定对急性脑干损伤的死后诊断具有参考价值。     

利用尸体软组织生物力学性状时序性变化推断死亡时间

目的探讨尸体软组织生物力学性状时序性变化规律及其推断死亡时间的可行性。方法将实验大鼠用颈椎脱臼法处死,放置25℃恒温培养箱内即刻、6、12、18、24、30、36、42、48、60、72、96、120、144、168、192h,定时、定位、定向、定形切取大鼠胸部正中皮肤、腹壁肌肉、胸主动脉、结肠和小肠的生物力学试件,用电子万能材料试验机检测各试件的极限载荷、应变、应力生物力学参数。结果除主动脉外,尸体皮肤、肌肉、小肠、结肠的各项软组织生物力学参数均呈明显的死后时序性下降趋势。各参数下降趋势具有显著性差异的＂窗口期＂分别为：极限载荷：死后18h内皮肤、小肠呈下降趋势;24h内肌肉、结肠呈下降趋势;96～168h肌肉呈下降趋势;72～192h结肠呈下降趋势。应变：各组织在24h内均呈下降趋势,其结肠72～192h缓慢下降趋势。应力：皮肤18h内呈下降趋势,肌肉、小肠24h内呈下降趋势,结肠36h内呈下降趋势。结论大鼠尸体软组织各生物力学性状在不同的＂窗口期＂存在时序性变化规律,综合各指标可用于推断相应＂窗口期＂内的死亡时间。     

大鼠脑损伤后GDNF表达变化的时间规律性研究

目的探讨大鼠脑损伤后胶质源性神经营养因子(GDNF)在神经元、神经胶质细胞中表达变化的时间规律性。方法以冲击应力σd为355.09kPa致大鼠脑损伤后,于不同时问段分别应用原位杂交、免疫组化、免疫组化双染色技术检测GDNF mRNA和蛋白的表达强度,用图像分析系统测定阳性反应物平均灰度,进行统计学分析。结果正常对照组GDNF mRNA和蛋白弱表达,伤后15min开始表达呈增强趋势,分别于伤后1d、2d,表达至峰值,平均灰度值分别为133.08±4.53、125.05±2.00,与对照组、邻近上组比较均具有显著性差异(P<0.05),并维持高水平表达至伤后7d,平均灰度值分别为116.65±1.31、114.20±1.68,与对照组比较具有显著性差异(P<0.05)。表达至峰值前,阳性细胞多为神经元,之后以神经胶质细胞为主。结论脑损伤后GDNF mRNA及蛋白的表达具有时间规律性,GDNF阳性细胞种类存在变化,可作为法医学推断脑损伤形成时间的指标。     

Cathepsin-L在缺血心肌中的表达

目的检测cathepsin-L(CTSL)在大鼠早期缺血心肌中的表达变化,并探讨其法医学意义。方法建立大鼠早期心肌缺血模型,设置早期缺血组(early ischemic myocardium,EIM)、非缺血组(non-ischemic myocardium,NIM)、假手术组以及空白对照组,采用real-time PCR方法检测大鼠缺血后15min,30min,1h和2h CTSL mRNA的表达量,并进行组内和组间比较。收集心源性猝死者缺血心肌和机械性损伤致死者正常心肌样本,采用免疫组化染色方法观察心肌组织中CTSL蛋白表达。结果 EIM组CTSL mRNA表达量与NIM组、假手术组及空白组相比,在15min时无统计学意义(P>0.05),在30min、1h和2h时分别升高1.4、3.1和4.5倍(P<0.05);其余3组间差异无统计学意义(P>0.05)。观察10例冠脉狭窄程度Ⅲ～Ⅳ级的心源性猝死(SCD)者缺血心肌,CTSL表达增强。结论大鼠心肌缺血后早期即可检测到CTSL mRNA的升高,并在SCD冠脉狭窄死者缺血心肌中高表达,提示CTSL可作为心肌缺血与SCD的参考指标。     

Chronic Alcohol Abuse Leads to Low Bone Mass with No General Loss of Bone Structure or Bone Mechanical Strength,

Chronic alcohol abuse (CAA) has deleterious effects on skeletal health. This study examined the impact of CAA on bone with regard to bone density, structure, and strength. Bone specimens from 42 individuals with CAA and 42 individuals without alcohol abuse were obtained at autopsy. Dual‐energy X‐ray absorptiometry (DEXA), compression testing, ashing, and bone histomorphometry were performed. Individuals with CAA had significantly lower bone mineral density (BMD) in the femoral neck and significantly lower bone volume demonstrated by thinner trabeculae, decreased extent of osteoid surfaces, and lower mean wall thickness of trabecular osteons compared to individuals without alcohol abuse. No significant difference was found for bone strength and structure. Conclusion: CAA leads to low bone mass due to a decrease in bone formation but with no destruction of bone architecture nor a decrease in bone strength. It is questionable whether this per se increases fracture risk.     

Effects of obesity on talar micro- and macro-morphology

The addition of information regarding obesity status to the forensic anthropological biological profile could significantly contribute to the identification of human skeletal remains since over 40% of the U.S. adult population is currently obese. This study examines the differences in talar shape and trabecular bone structure between obese and non-obese individuals. A sample of 20 obese and 20 non-obese divided evenly by sex was selected from the Texas State University Donated Skeletal Collection. Tali were imaged using x-ray computed tomography (voxel size: 28–38.7 μm). Image stacks were processed to produce binary images as well as trabecular thickness and spacing maps. Landmark-based geometric morphometric analyses were conducted to quantify shape variation. Shape coordinates were used to locate 100 geometrically homologous volumes of interest within each talus. Bone volume fraction, trabecular thickness, and trabecular spacing were extracted at each volume of interest. Within each sex, a one-way ANCOVA was used to determine if significant differences exist between obese and non-obese individuals in trabecular bone after controlling for age. The size of the talus as well as subtle aspects of shape were found to distinguish the sexes. The results further indicate that bone volume fraction significantly differs between obese and non-obese males. In females, bone volume fraction is correlated with age but does not differ between obese and non-obese. The study demonstrates that bone microstructure is a promising approach to estimating body mass or body mass index category but age effects diminish the potential for the talus to be used alone.     

定量CT用于测量颅骨力学强度的实验研究

利用尸体颅顶骨标本80例，在用理化方法测定骨中水、盐及有机质成份比例和半静态抗弯、抗压力学实验的基础上，将标本首次进行矿物质含量（密度）的定量CT测定。运用统计学方法对定量CT测定值和骨质的抗弯、抗压强度之间的关系进行了分析。实验结果表明，颅顶骨抗弯强度与颅项骨松质的矿物质含量和颅项骨抗压强度与颅顶骨内板皮质矿物质含量之间存在较好的正相关，其相关系数分别为O．51和O．34（P＜0.01）。     

中国汉族成人肱骨近端CR片特征与年龄的相关性

目的探讨中国汉族成人肱骨近端CR片的特征随年龄变化的规律,以推断年龄。方法 210例中国汉族成人肩关节CR片,其中男性124例,年龄范围18~83周岁,女性86例,年龄范围18~60周岁,选取与年龄变化关系密切的肱骨骨髓腔高度、肱骨近端骨骺骨小梁变化、肱骨大结节内骨小梁变化、锁骨骨髓腔肩峰侧骨小梁变化4项指标,观察不同年龄各指标的变化进行统计分析。结果四项指标均是影响年龄变化的重要因素。肱骨近端骨骺骨小梁变化、锁骨骨髓腔肩峰侧骨小梁变化对年龄的预测影响较大,肱骨骨髓腔高度、肱骨大结节内骨小梁变化稍小。利用以上指标建立的回归方程能很好的反映成人肱骨的增龄性变化,预测骨龄较为准确。结论利用成人肱骨骨髓腔高度、肱骨近端骨骺骨小梁变化、肱骨大结节内骨小梁变化、锁骨骨髓腔肩峰侧骨小梁变化可推断年龄。     

Age estimation through histological study of trabecular volume and cortical bone width of the iliac crest

There have been many methods proposed to estimate the age of human bones in forensic medicine or in forensic anthropology, including those that assess histological structures. In this study, age was evaluated through the histomorphometric study of trabecular volume and cortical width of the right iliac crest. A total of 25 samples A total of 66 samples (42 male and 24 female) were obtained from necropsies of judicial cases, with ages ranging from 13 to 58years, who had died a sudden or violent death. The samples were obtained using Bordier's trocar for bone biopsy, in a period not exceeding 24h after death. The samples were examined without decalcification, with 96° alcohol dehydration, embedding in methyl methacrylate, and sectioned with a microtome Reichert (3μm). The sections were fixed on microscope slides and stained using toluidine blue, Goldner trichrome and hematoxylin-eosin methods. The samples were studied under a Leica DM LB microscope and the images were digitally captured. The digital images were processed using an image analysis program and data were analyzed using the SPSS statistical package. The results demonstrated that the combination of the trabecular volume and cortical width acted as predictors of the age in subjects which did not suffer from any deterioration of bone and/or mineral metabolism.     

Iliac cancellous bone in drug addicts: a histomorphometric study

Histomorphometry was used to determine structural bone changes in drug addicts. Iliac crest bone biopsies were obtained at autopsy from 28 subjects (21 male, 7 female, aged 18 to 45 years) who had a history of drug abuse and had died due to overdose of illicit drugs. For histomorphometry, undecalcified sections were investigated using the Merz grid. The following histomorphometric indices were measured and calculated: BV/TV, BS/BV, Tb.Th, Tb.N, Tb.Sp, OV/TV, OS/BS, Ob.S/BS, O.Th, ES/BS, Oc.S/BS, and N.Oc/T.A. In 28 controls (24 male, 4 female, aged 17 to 47 years) trabecular bone specimens were investigated in the same way. The parameters in drug addicts did not show any correlation to age, body weight, height or sex differences. Trabecular bone volume and trabecular thickness were slightly but not significantly increased (BV/TV: 23.37 +/- 5.77% (mean, SD), controls 22.23 +/- 5.08%, p = 0.434; Tb.Th: 172.67 +/- 36.83 mcm, controls 169.73 +/- 36.13 mcm, p = 0.764). Only the eroded surface was significantly different to the controls (ES/BS: 8.16 +/- 2.04%, controls 6.96 +/- 2.17%, p = 0.038). We conclude that the incidence of metabolic bone disease in drug addicts is low.     

Cranial thickness in relation to age, sex and general body build in a Danish forensic sample

The cranial thickness was measured in 64 individuals (43 males, 21 females) autopsied at our institute. The thickness was measured by taking a biopsy with a trephine at four specific locations on the skull. Complete medical records and pathologic autopsy results were available. While none of the individuals had suffered from diseases affecting bone or bone metabolism as such, a large sub group consisted of individuals with a history of, and autopsy finds consistent with, chronic substance and alcohol abuse. There was no statistically significant difference in cranial thickness measures between this group and the rest of the material. Subsequent analyses failed to reveal any correlations between the cranial thickness and sex and age and height and weight of the individual. This is in accordance with most earlier studies, which likewise show no correlation, or only very faint trends, between cranial thickness and these parameters. This study, thus, adds to other studies showing that cranial thickness cannot be used in aging or sexing human remains. Likewise, in a forensic pathological setting, cranial thickness cannot be inferred from the individuals stature and build, which may be an issue in cases of interpersonal violence with cranial trauma.     

Forms of fractures of the occipital condyles

In contrast to the large fracture system of the base of the skull, little attention has so far been paid to fractures of the occipital condyles. The mechanics of these fractures have mostly been described in the form of case reports. Here an attempt is made to classify fractures of the occipital condyle based on the literature and our own material. Fractures of the condyles in the sense of bursting or the injuries themselves are classified under the following forms of strain: 1. Axial compression (Jefferson type) condylar impression; 2. Axial traction (hangman's type) condylar retraction; 3. Rotation with axial strain condylar retraction; 4. Oblique compression (bursting fracture of the abutment) frontal condylar fracture; contralateral; 5. Oblique traction (horizontal thrust); a tearing at the base of the skull as in a contralateral condylar horizontal fracture; 6. Transverse thrust (longitudinal fracture of the base of the skull) partial condylar avulsion The functional connection between a longitudinal clivus and condylar fracture is illustrated by typical examples. Furthermore, the elliptical deformation model for a burst fracture at the base of the skull in the longitudinal axis is extended by the deeper transverse thrust stabilization of the condyles.     

Age-specific changes in bone tissue microstructure and potential for use for human identification

The possibility of using the data of quantitative microscopy of bone tissue for evaluation of age with the aim of personality identification is discussed. Computer histomorphological analysis of third rib, tibial lower epiphysis and diaphysis fragments from 564 male corpses of known age (0-90 years) was carried out. A complex of parameters most strongly correlating with age was detected: extension of active osteogenesis zone in the longitudinal section of a rib, thickness of layers of internal and external general diaphyseal laminae in the tibial bone, trabecular area in the tibial epiphyseal preparation, etc. Age-specific changes in bone tissue structures is characterized by a great variety and depends on the type and location of these structures. Bone tissue characteristics change irregularly and asynchronously, therefore their correlations with age are different in different age groups. A general biological interpretation of the results is offered.