Preservation of stab and cut wounds of the skin

The authors compare different methods of fixation of stab and cut wounds of the skin. Fixation in formalin has more disadvantages than advantages despite its vast application. In our opinion fixation in formalin-free solution leads to better results especially with regard to subsequent investigations carried out later on. The best results were found with a modification of the Dietrich-Ratnewski fixing solution. This contains acetic acid, absolute alcohol, glycerin and water in the volume ratios 10: 15: 5: 70.     

Forensic photography. Ultraviolet imaging of wounds on skin

The use of ultraviolet light (UVL) to study and document patterned injuries on human skin has opened a new frontier for law enforcement. This article discusses the photographic techniques involved in reflective and fluorescent UVL. Documentation of skin wounds via still photography and dynamic video photographic techniques, which utilize various methods of UV illumination, are covered. Techniques important for courtroom presentation of evidence gathered from lacerations, contusions, abrasions, and bite marks are presented through case studies and controlled experiments. Such injuries are common sequelae in the crimes of child abuse, rape, and assault.     

Enzyme activities of leukocytes in skin cut wounds with various wound ages

A study was carried out on leukocyte enzyme activity from prints of skin cut wounds of guinea pigs at various time intervals after the injury. The following enzymes were examined: alkaline and acid phosphatase, succinate, lactate, and glucose-6-phosphate dehydrogenases. Cytochemical analysis revealed a rapid increase in enzyme activity in the 4th h after the wound occurred, which can be explained by the alteration in leukocyte metabolism induced by the damaging agent, i.e., the skin trauma inflicted. The rise in lactate dehydrogenase and glucose-6-phosphate dehydrogenase activity is the most characteristic feature. In accordance with these changes in enzyme activity, some conclusions can be made about certain intracellular alterations. There is a close relationship between the course and the degree of these cellular changes and the time interval between the injury and examination of the enzyme activity. These changes make it possible to draw conclusions concerning the vital character and the interval after inflicting as well.     

Structural changes to the skin in the area of gunshot wounds]

Microscopic changes in skin structures around gunshot and stabbed wounds, which may be used as features characterizing injury volume were studied. Factors influencing the significance of these changes were presented and mechanisms of their occurrence is discussed.     

对女性肋骨进行组织形态测量推断年龄

探讨人类密质骨的年龄变化规律 ,为法医学、人类学利用骨骼推断年龄提供新方法。收集 6 7例中国北方汉族女性右侧第六肋骨的中 1/3段 ,制作脱钙骨切片 ,在计算机图像分析仪上测量 9项组织形态学参数 ,并进行多元逐步回归分析 ,得到一个推断年龄的多元回归方程 :^Y =31 2 6 4+0 86 8X2 +2 86 6 93X4 +0 6 89X7-778 874X8-0 0 0 6X9,复相关系数和标准误分别是 0 92 3和 4 0 8。经 2 5例已知年龄的标本检验 ,预测年龄的误差在± 5岁以内的可达 84% ,误差在± 8岁以内的可达 10 0 %。结果表明 :应用肋骨的组织结构特征可准确推断死者年龄     

Transforming growth factors (TGF-alpha and TGF-beta1) in the determination of vitality and wound age: immunohistochemical study on human skin wounds

In continuation of former investigations on proinflammatory cytokines, in the present study the relevance of the transforming growth factors TGF-alpha and TGF-beta1 was evaluated for the diagnosis of vitality and wound age. Paraffin sections from human skin wounds due to sharp force influence, which had been collected in operations and autopsies, were investigated using immunohistochemistry. The wound age varied from a few minutes to a maximum of 6 weeks with focus on the early post-traumatic interval up to 5h. Samples from uninjured skin were available as controls. TGF-alpha (n=74) was weakly expressed in normal skin and showed a marked increase in epidermal reactivity after a wound age of approximately 10 min. The maximum was between 30 and 60 min. TGF-beta1 (n=51) revealed constitutional expression only in connective tissue. An increase of immunohistochemical reaction was partially detected even in classical stab wounds (wound age of several minutes). The immunohistochemically detectable signal concerned--presumably due to an infiltration with TGF-beta-rich thrombocytes--large parts of the traumatized skin and also the epidermal layers (cellular and interstitial marking). TGF-beta1 peaked after a post-traumatic interval of 30-60 min. Both factors, especially TGF-beta1, remained detectable in elevated levels also in older wounds with an age of days to weeks (network in granulation tissue). TGF-alpha and TGF-beta1 can efficiently contribute to the estimation of vitality and wound age based on the evaluation of cytokine patterns. In particular, this applies to TGF-beta1 because of its easier evaluation and rapid up-regulation. Similar to other cytokines, the parallel investigation of control skin from the same individual must be recommended to eliminate variation in the basal expression.     

Expression of adhesion molecules in skin wounds: diagnostic value in legal medicine

The adhesion molecules identified in recent years can help improve the diagnosis of the wound age, especially of injuries with a short survival time. This is also indicative of the vitality of the wounds. The material investigated in the study originated from 465 skin wounds. The samples were taken from human autopsy material, during the surgical treatment of wounds (excision) of patients and from experimental incised wounds of mice. To judge the age of skin wounds the endothelial adhesion molecules were detected in paraffin sections after autoclaving and using the ABC technique. Human skin wounds: strong positive staining was observed of ICAM-1 1.5 h at the earliest and 3.5 days at the latest, for the P-selectin 3 min at the earliest and 7 h at the latest, for the E-selectin 1 h at the earliest and 17 days at the latest and for VCAM-1 3 h at the earliest and 3.5 days at the latest after the time of injury. The L-selectin was expressed constitutively. Mice skin wounds: strong positive immunohistochemical reactions were found as a rule earlier than in human skin wounds. The detection of an increased expression of ICAM-1, VCAM-1 and P- and E-selectins can improve the wound age assessment in injuries with short survival times.     

Psychological factors in the determination of suicide in self-inflicted gunshot head wounds

Self-inflicted contact gunshot wounds to the head have usually been considered presumptive of suicide. This study evaluates whether sufficient psychological data are gathered in such cases to support a manner of death determination of suicide. We suggest that law enforcement agencies and coroner's departments do not fully explore the decedent's state of mind at the time of death. We studied the first 50 consecutive deaths in 1993 in a major metropolitan county due to self-inflicted gunshot wounds to the head. The sample consists primarily of unmarried, white males, with a median age of 35 years, who displayed psychiatric disturbance, primarily depression, before their death. Younger individuals were often under the influence of alcohol and/or drugs at the time of death. Stressors, such as the loss of a loved one, are common among young and middle-aged persons, while serious health problems are found among the majority of middle-aged and elderly individuals. Many of the findings of this study are consistent with the literature regarding individuals who commit suicide. Although data on many important psychological risk factors are missing in most cases, sufficient psychological material is gathered about the decedent's mental condition at the time of death to support a suicide determination.     

Age determination of an unknown body in early adulthood

The authors report on the estimation of the age of an unidentified deceased adolescent in connection with the body's identification. A physical examination by a forensic physician and an examination by a forensic dentist, including determination of the dental status and an X-ray of the teeth were used to estimate the age. In addition, an X-ray of the left hand as well as an X-ray and MRT scan of the clavicles were carried out by forensic radiologists. Combining the results of the individual examinations, the age of the deceased was estimated to range between 18 and 21 years. In the course of the police investigation it was found out that the deceased was 20 years and 7 months old. This has led to the conclusion that combined use of methods allows the age even of adolescents to be determined with relatively high accuracy and a minimum of time and effort.     

The macro- and micromorphological signs of the edge of stabbing-cutting weapons in skin wounds

110 stab-cut skin wounds in 34 dead bodies as well as 38 stab-cut instruments were studied. Three morphologic types of traces left by blade edges of stab-cut instruments, i.e. puncture, microrupture and microcut, were established. Gross and micromorphology of each of these traces depends on the properties of blade edges of stab-cut instruments.     

Gunshot residue patterns on skin in angled contact and near contact gunshot wounds

The goal of this study was the reproduction of shape and pattern of gunshot residues in near contact and contact gunshot wounds by a series of experimental gunshots on a skin and soft tissue model. The aim was to investigate the shape and direction of soot deposits with regard to the muzzle according to different muzzle-target angles, firing distances, type of ammunition and weapon and barrel length. Based on a review of the literature and on the results of the experiments the authors could make the following statements of gunshot residues in angled contact and close contact gunshot: (1) gunshot residues on the target surface can be differentiated in a "inner" and "outer powder soot zone"; (2) the outer powder soot zone is much less visible than the inner powder soot zone and may lack on human skin; (3) with increasing muzzle target distance both inner and outer powder soot halo increase in size and decrease in density; (4) in angled shots the inner powder soot halo shows an eccentric, elliptic shape which points towards the muzzle, regardless of ammunition, calibre and barrel length; (5) the outer powder soot points away from the muzzle in angled contact and close contact shots.     

大鼠皮肤挫裂创细胞间粘附分子-1的表达

目的 观察大鼠皮肤钝器伤后细胞间粘附分子-1(ICAM-1)表达的变化规律。方法 应用免疫组化方法,观察大鼠皮肤钝器伤后1h、3h、6h、12h、1d、3d、5d、7d、9d ICAM-1的表达情况,并用MIAS图像分析系统进行图像分析。结果 正常对照组大鼠皮肤有低水平ICAM-1表达,钝器伤后ICAM-1表达增加,伤后7d达峰值,伤后9d开始下降。结论 皮肤钝器伤可诱导ICAM-1表达增加,其时序性变化可望作为一种客观指标用于法医学损伤时间的推断。     

Study of elastic fiber changes of human skin in distinction between antemortem and postmortem wounds

Elastic fiber changes of volunteers' antemortem and postmortem skin wounds of various time were observed in order to find possible differences between them. These sections of the wounds were stained by Hart's modification of Weigert's elastic tissue stain.. However, this study showed that there were no differences in the nature and distribution of the elastic fibers in the dermis of volunteers' antemortem and postmortem human skin wounds. Therefore, this suggests that the appearances of the elastic fibers in the dermis should not be as a means of differentiating antemortem skin wounds from postmortem wounds in forensic identification.     

Localization and quantification of the nonspecific esterase in injured skin for timing of wounds.

Histochemical quantification of the nonspecific esterase (NSE) in injured skin was performed using histochemical demonstration of the enzyme and a microspectrophotometric scanning technique on specimens taken from 32 Hartley guinea-pigs and 8 cases of human skin wounds. In all antemortem incisions and lacerations, including those made at the agonal stage, NSE activity could be observed in the dermal tissue of the wound edge. The enzyme activity increases with the antemortem duration of the injuries. Both total content and mean concentration of NSE in the wound edge between antemortem and postmortem wound groups differ significantly (less than 0.01). Multiple range test shows that significant differences (P less than 0.05 or P less than 0.01) of total content of NSE in the wound edge also exist in 0-5 min, 15-30 min, 1-h, 2-h and 4-h antemortem incised wound groups and in 0-min, 5-min, 15-30 min, 1-h and 4-h antemortem laceration groups. The positive NSE reactions in 8 cases of human skin wounds were similar. The study indicates that histochemical quantification of NSE in injured skin is very useful in timing wounds and is exactly applicable in medicolegal practice. According to the different influences of inhibitors on enzymes, it was inferred that the enzyme activity in wound edges was due to B-esterase.