Zur ultrastruktur vitaler,postmortaler und autolysierter gerinnsel

Investigations on animal experimental and human tissue material (skin, musculature, liver) with the scanning electron microscope are reported. These studies were carried out to clarify open questions on extravascular fibrin structures after blunt and sharp traumatization of vital and postmortem nature. The network formation which was already characterized earlier as typically vital and the irregular structure of postmortem coagula could be demonstrated even with modification of the traumatization, especially in tissue hematomas. Experimental investigations on autolysis revealed an exceedingly good preservation of the structure of vital coagulum material with massive damage and granular decomposition of fibrin fiber structures produced postmortem. The structural differences in the mode of interlinking of the fibrin was shown up especially clearly by the autolysis, which suggests an application as preparation technique for the question specified.Special modifications of the preparation technique (fixation according to Karnovsky, critical-point drying) did not provide such substantial advantages for routine investigations that they might be generally recommended.Sources of artefacts and possibilities of misinterpretation of findings as well as more advanced techniques are discussed.     

Tool mark striations in pig skin produced by stabs from a serrated blade

Stab wounds produced by serrated blades are generally indistinguishable from stab wounds produced by non-serrated blades, except when visible tool mark striations are left on severed cartilage. Using a pig-skin experimental model, we explored the possibility that similar striations may be left in skin. Stabs into pig skin were made using a straight spine coarsely serrated blade (121), a drop point finely serrated blade (20), a clip point irregular coarsely serrated blade (20), a drop point coarsely serrated blade (15), and as controls 2 non-serrated blades (40). Tool mark striations could be seen on the skin wall of the stab canal in all stabs made using serrated blades but in none with non-serrated blades.The striation pattern, reflecting the class characteristics of the serrated blade, was the same as that described in cartilage but less well defined. Fixation of the specimen with Carnoy's solution best preserved visible striations, and fixation with formaldehyde after staining with 5% Neutral Red was also satisfactory. Casting with vinyl polysiloxane dental impression material greatly facilitated photo-documentation. Applying the technique to homicidal stabbings may help identify stab wounds produced with serrated blades.     

PAP免疫组织化学技术检测血小板膜糖蛋白

<正> 血小板膜糖蛋白 GPⅠ_b 和 GPⅢa 在血小板粘附、聚集中起着极其重要的作用。为了直接检测组织中血小板粘附、聚集和血栓形成,我们建立了应用抗人血小板膜糖蛋白 GPⅠ_b和 GPⅢa 的单克隆抗体的 PAP 免疫组织化学技术,并首次对该技术在法医学中的应用进行了初步探讨。     

The effect of skin cleansing agents on ethanol results measured with the Du Pont automatic clinical analyzer

The effect of various prepackaged skin cleansers on the results of serum ethanol analyses performed with the Du Pont automatic clinical analyzer has not been previously reported. When added directly to serum in concentrations of either 0.625 or 1.56% (v/v), neither polyvinyl-pyrrolidone iodine nor benzalkonium chloride affected the ethanol results. The cross-reactivity of isopropanol with the automatic clinical analyzer ethanol procedure was 3.9%. The greatest interference in the measured ethanol concentration was from the addition of green soap tincture, which contained 30% ethanol. The effect of improper phlebotomy technique on ethanol measurements was also investigated by performing venipunctures through a pool of 100% ethanol on the skin. No ethanol was detected in these samples unless an ethanol-soaked sponge was pressed over the venipuncture site while the needle was withdrawn from the skin. When correct phlebotomy technique is used, skin cleansing agents should not affect the results of ethanol measurements determined with the Du Pont automatic clinical analyzer.     

大鼠皮肤切创愈合过程中泛素的表达及其法医学意义

目的观察大鼠皮肤切创后泛素(ubiquitin)表达的变化规律。方法应用免疫组化方法,观察大鼠皮肤切创后1、3、6、12h和1、3、6、10、14d ubiquitin的表达情况,并用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ubiquitin表达,切创后ubiquitin表达增加,伤后6d达峰值,伤后10d开始下降,伤后14d恢复到正常水平。结论ubiquitin可作为法医学损伤时间推断的有效指标。     

Bite marks: physical properties of ring adhesion to skin-phase 1

Abstract: Unsupported excised skin may shrink by as much as 50% or more. In 1981, a method was developed for ring adhesion to skin with the goal of minimizing tissue distortion upon excision. Five modified versions of the technique bearing the author’s name followed (Dorion types I, II, III, IV, and V). The scientific literature reveals little supporting empirical evidence for the preferential use of one adhesive/suturing technique over another. This study compares the use of various bonding materials (Loctite Super Glue gel^®, Dermabond?, Vetbond?), cleaning agents (ethanol, dishwashing liquid, and shaving cream), and depilatory (Veet^®) on the effects of ring adhesion to skin. The conclusions indicate that surface wetness is the most influential factor affecting ring adhesion to skin, followed by the type of bonding material, its “freshness,” and by the cleaning agent used to prepare the skin. The use of a depilatory or shaving cream is to be avoided.     

Vital reactions to frostbite of the ear and paw skin in guinea pigs exposed to the cold

Vital reactions to frostbite in the paw and ear skin of guinea pigs were studied in order to find an animal model for frostbite in cases of accidental hypothermia. One group of animals was rendered hypothermic (rectal temperature, 30 degrees C) by exposure to an ambient temperature of -20 degrees C, and samples were taken from the frozen skin. A second group was rendered hypothermic and rewarmed in warm air at 45 degrees C, and samples were taken from the thawed skin. The only vital reaction in the first group (freezing time, 4-5 h) was mild initial inflammation, which was expressed in granulocyte adhesion to the vessel wall and the migration of a few cells into the dermis. The inflammatory reaction was more distinct in the second group (freezing and thawing together 5-7 h), with a large number of granulocytes being present in the dermis. Oedema and hyperaemia were also present in the frostbitten tissue after thawing, but no signs of necrosis developed. The alkaline-phosphatase reaction demonstrated the presence of granulocytes more clearly than H & E or Masson trichrome staining. Vital reactions were more advanced in the ear skin. It is concluded that vital reactions are very scarce in cases of frostbite, even after several hours' exposure, unless the tissue is allowed to thaw.     

大鼠皮肤切创后E-选择素表达及稳定性研究

目的探讨大鼠皮肤切创后E-选择素表达规律及法医学意义。方法健康SD大鼠90只,随机分成4组：正常对照组、活体切创组（30min～7d12个时间点）、死后切创组（30min～3h3个时间点）、死后稳定性组（-20％6h-7d9个时间点,25％6h～3d5个时间点）。在大鼠头部建立皮肤切创模型,按设定的时间点取皮肤检材,运用免疫组化和图像分析技术,检测血管内皮E-选择素的表达规律。结果在活体切创组中,伤后1hE-选择素在血管内皮细胞内即呈阳性表达,持续至伤后7d,且随时间变化呈规律性表达。在正常对照及死后切创组未见阳性表达。死后-20％稳定性组各时间点E-选择素表达与死后即刻比较无显著性差异（P〉0．05）。25％各时间点与死后即刻比较有显著性差异（P〈0．01）。结论E-选择素在创伤后血管内皮细胞内特异性的表达具有时序性规律,且低温条件下稳定性较好。     

大鼠 Fn剪接异型体分布及皮肤损伤后表达研究

目的研究成年大鼠、新生幼鼠纤维连接蛋白剪接异型体 EⅢ A、 EⅢ B体内分布及皮肤切创、挫伤后表达情况 , 以期为法医学损伤经历时间研究探索新指标及选择阳性对照 . 方法组织匀浆后抽提总 RNA, 逆转录聚合酶链反应 ( RT- PCR) 技术扩增目标条带 . 结果 (1)正常皮肤 EⅢ A+ 、 EⅢ B+ 不表达 , 伤后 18h EⅢ A+ 位点高丰度表达 , EⅢ B+ 位点变化不明显 , 两种致伤方式表达结果差别不大 ; (2)成年大鼠各器官分布情况依次为脑、心、肝 . 结论 EⅢ A+ 可作为皮肤损伤研究的敏感指标 .     

单细胞检验技术用于混合上皮细胞的分离和检验

目的建立单细胞显微捕获联合低体积扩增技术,用于混合上皮细胞检材分离检验。方法取5名男性口腔上皮细胞拭子浸泡液30μL,分别滴加到5份含同一女性皮肤表皮细胞拭子上,制成5份混合上皮细胞样本为实验组,同时制备同样的5份样本为对照组。实验组样本采用显微捕获单个口腔上皮细胞,并使用低体积扩增技术进行扩增;对照组用M48纯化试剂盒提取DNA,Identifiler试剂盒复合扩增,扩增体系为10μL。所有产物均用ABI 3130遗传分析仪进行STR分型。结果 5份实验组样本均得到男性STR分型结果,5份对照组样本则均仅得到混合分型结果。将该方法应用于1例强奸杀人案例检验,取得了满意效果。结论单细胞显微捕获联合低体积扩增技术可用于混合上皮细胞样本的分离检验。     

The detection and analysis of ignitable liquid residues extracted from human skin using SPME/GC

A simple, fast, inexpensive, and sensitive technique for the detection and identification of flammable or combustible liquid residues on the skin of arson suspects is presented. The use of solid phase microextraction (SPME) for the analysis of ignitable liquid residues has been demonstrated and it is shown in this work that this technique is effective in extracting these liquid residues at extremely low quantities. Microliter quantities of controlled spikes of gasoline, diesel fuel, and charcoal lighter fluid were deposited on the hands of a volunteer and extracted after several time intervals. The SPME technique can recover very small amounts of liquid deposits on skin up to 3.5 h after exposure, depending on the class of the ignitable liquid residue used.     

大鼠皮肤降钙素基因相关肽表达与损伤时间的相关性

目的探讨创伤皮肤组织降钙素基因相关肽(CGRP)的时间相关性表达,为损伤时间推断提供实验依据。方法应用免疫组化技术、图像分析技术和原位分子杂交技术检测不同损伤时间大鼠皮肤组织生前及死后CGRP表达。结果生前组大鼠损伤后皮肤组织内CGRP在神经纤维中表达明显高于对照组(P<0.05)。死后组皮肤组织中CGRP表达与正常对照组比较无明显变化(P>0.05)。生前组中CGRP表达在损伤后1h明显增多,4h达到高峰,以后恢复到正常。结论损伤组织神经纤维中CGRP表达具有规律性且有较好的时间相关性,可成为法医学损伤时间推断的指标。     

受虐儿童眼内改变的多媒体计算机研究

本研究在传统计算机应用的基础上，综合应用多媒体计算机，视窗下多媒体创作工具等技术，结合法医学实际，研制出受虐儿童眼内改变的多媒体计算机系统。对于提高法医学工作质量，跟踪国际先进技术具有重要意义。展望多媒体计算机在法医学鉴定、法医学教育、法医学科研等方面的应用在深度和广度方面会有更大的发展。     

A rapid method to detect dried saliva stains swabbed from human skin using fluorescence spectroscopy

Saliva on skin is important in forensic trace evidence. If areas where saliva is present can be outlined, this may lead to DNA analysis and identification. This study describes a rapid and non-destructive method to detect dried saliva on the surface of the skin by fluorescence spectroscopy. Eighty-two volunteers deposited samples of their own saliva on the skin of their ventral forearm. A control sample of water was deposited at three different sites on the contralateral arm. Saliva and water control were then allowed to air-dry. Swab samples were taken from dried saliva and control sites and were dissolved in 0.1M KCl solution. Emission spectra were obtained from the solution and were characterized by a principal maximum at 345-355nm with excitation at 282nm. The fluorescence emission intensity was greater than background readings obtained from the control swab site in 80 of 82 volunteers (approximately 97.6%). The fluorescence profile of saliva samples were similar to those obtained from aqueous samples of pure amylase and tryptophan, an endogenous fluorophore in alpha-amylase. The presence of an emission peak at 345-355nm with excitation at 282nm could provide a strong presumptive indication of saliva deposition.     

Forensic applications of sodium rhodizonate and hydrochloric acid: a new histological technique for detection of gunshot residues

Demonstration of the presence of lead residues deriving from gunshot in skin and underlying tissues is essential for the correct forensic analysis of numerous legal cases. Optical microscopy remains the fastest, cheapest diagnostic technique, even though its sensitivity and specificity are poor because of the scarce quantity of histological tissue that can be examined and possible environmental lead pollution. To confirm the presence of lead from gunshot residues, we applied to histological sections of human skin a technique proposed by Owens and George in 1991 for macroscopic detection of lead on the clothing of shooting victims, involving a reaction with sodium rhodizonate and subsequent confirmation by color change on application of HCl. Our results demonstrate the technical possibility of using this macroscopic technique even on histological samples and support the need for further studies on a larger series of cases correlated with the type of ammunition and firing distance.     

Homicide or accident off the coast of Florida: trauma analysis of mutilated human remains.

In the many years Dr. William R. Maples served as a forensic anthropologist, he saw diverse sources of trauma presented in the victims of violent crime, accident and suicide in the state of Florida. In 1996 the District 18 Medical Examiner's Office of Florida requested the assistance of Dr. Maples in the analysis of human remains recovered by the U.S. Coast Guard. The deceased was in an advanced state of decomposition characterized by skin slippage and discoloration. The torso bore multiple lacerations, including nearly parallel lacerations in the skin of the back. Specimens were carefully macerated and the fractures reconstructed. The skeletal trauma was caused by a device capable of delivering robust cuts and blunt trauma in linear paths, as is consistent with propeller trauma. Unusual in this case were blows to the ventral and dorsal surfaces of the body. Based on the anthropological analysis and interviews with the family of the deceased, the F.B.I. proceeded with the case as a homicide investigation.     

Value of laryngeal injuries as evidence

Report of two cases: Violations at soft parts of the neck and at larynx pointed to an attack against the throat by strange hand, but local vital reactions showed that the attack had been survived. A 54-year old woman had little excoriations in the skin of the neck, the right great horn of hyoid bone and the left upper process of thyroid cartilage were broken, the fractures were bloodshot. No petechiae in skin and conjunctivitis. Death occurred from a suicidal poisoning of soporifics. The attack against the throat (throttling by hand, conceded by the culprit) had been survived. That was recognizable on a clear cell-reaction in the bleedings within the muscles of the neck. A 87-year old man was found in his rummaged home. Violations of the skin in the face pointed to attacks against mouth and throat; additional maltreatment by gagging and fettering (in the meantime untied) could be supposed. -- Histological examination showed advanced cell-reaction in the wounds, partially even intracellular iron pigment; there was a superposition of old and recent injuries, but even the recent had been survived many hours. The situation of finding the corpse, bleedings inside the iliac muscles, little hemorrhages in the mucosa of the stomach and acetone in blood and urine pointed to a death lately from cold. But complete clearing-up of the case was not yet possible.     

Diagnostic ability of D-dimer in the establishment of the vitality of wounds

The potential of skin measurements of D-dimer (DD), a specific derivative of crosslinked fibrin, for the diagnosis of the vital origin of wounds was investigated in 67 human vital skin wounds and homolateral control pieces of skin from 53 autopsies performed at the Institute of Legal Medicine of Coimbra (Portugal) during 1992. Our results demonstrate that DD levels for the incised vital skin wounds (n = 50) were much higher on average than their controls (P < 0.01) which were actually incised injuries produced postmortem at the autopsy. We did not find any statistical difference in average DD levels among the remaining injuries (seven abrasions and ten contusions) in comparison to their respective controls. DD may be used, with certain limitations, as a marker of the vitality of incised wounds. The authors believe this is the first time this marker has been applied in forensic pathology. It is an example of an easy and quick application technique, with the added advantage of low cost.     

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.