Early epidermal changes in heat- and electrically injured pig skin. I. A light microscopic study

In order to find methods applicable for disclosing electrical torture, pig skin was exposed to heat and electricity under controlled circumstances. Biopsies were obtained immediately after exposure and the morphology of the heat lesions was compared to that of electrical lesions. The cytoplasm of epidermal cells in heat lesions appeared granular or fibrillar, while the nuclei were rather unaffected. In electrical lesions the cytoplasm appeared homogeneous often with a peculiar white colour in hematoxylin-eosin stained sections. The nuclei were either dark and shadowy or enlarged and vesicular. The keratin in electrical lesions often showed a bright yellow colour. Small defects in the epidermis were seen in some electrical lesions. Thus the morphology of electrical lesions differed markedly from that of heat lesions. Although some of these differences may be due to differences in distribution and intensity of energy, it is probable that pH shifts in the cells due to electrolysis is the main cause of the specific morphology of electrical lesions.     

Adult respiratory distress syndrome. A histopathologic study.

The results of an anatomohistopathologic study carried out on subjects who died from various causes in resuscitation centers are reported with specific reference to the evolutive phases of the adult respiratory distress syncrome (ARDS). While a precise anatomohistopathologic diagnosis of non-clinically diagnosed ARDS in its initial phase is considered possible, the importance of recognizing this pathology in cadavers and living patients is emphasized because of the medico-legal implications involved.     

Early epidermal changes in heat- and electrically injured pig skin. II. An electron microscopic study

In order to find methods applicable for disclosing electrical torture, pig skin was exposed to heat and electricity under controlled circumstances. Biopsies for electron microscopy were obtained immediately after exposure. In heat lesions the nuclei were slightly distorted, sometimes with broken nuclear membranes. The tonofilaments were clumped, intracellular oedema was present and cell membranes were ruptured between desmosomes. In electrical lesions the nuclei were usually enlarged with strongly condensed chromatin. Some nuclei were composed of fine, evenly dispersed granular material. The cytoplasm appeared homogeneous, in large magnification finely granular. Cell borders could sometimes be identified located in situ. In the stratum corneum, which appeared normal in heat lesions, single or several cells or large areas had an electron-dense appearance. The difference in ultrastructure of heat and electrical lesions makes it probable that electricity has a specific action on epidermal cells.     

The application of histochemical methods to the age evaluation of skin wounds: experimental study in rabbits.

Enzyme histochemical methods allow determination of wound age, especially in the range of a few hours, and are used to distinguish between postmortem and antemortem skin wounds. The methods are based on the determination of the presence and changes of the enzyme reaction in the wound area. Increased activity of nonspecific esterases was observed approximately 1 hour after wounding and was followed by an increase in adenosine triphosphatase at approximately 2 hours and alkaline phosphatase at approximately 3.5 hours. Maximum enzyme activity was reached for nonspecific esterases at 24 hours, for adenosine triphosphatase at 20 hours, and for alkaline phosphatase at 32 hours after wounding.     

The morphogenesis of electrically and heat-induced dermal changes in pig skin

In order to establish pathological evidence in dermis for distinguishing between sequelae of electrical torture and those of other superficial injuries, the skin of eleven fully anaesthetized Danish Landrace pigs have been exposed to heat and electrical energy from either 50 Hz alternating current (a.c.) or direct current (d.c.) via 12 mm large contact knobs or via a pointed 0.5 mm large electrode (only 50 Hz a.c.). The lesions have been examined from 1 to 126 days after the injury. While heat lesions exposed to energy lower than 60 joule only gave minor changes, heat lesions exposed to more than 60 joule showed changes in both collagen fibres (basophilic or eosinophilic fibres without any birefringence or coarse cross-striation in polarized light, respectively) and dermal cells (granular cytoplasm). Areas exposed to 50 Hz a.c. via 0.5 mm. electrode showed basophilic collagen fibres and in a few biopsies on day 7 calcium salts on collagen fibres. Using 12 mm large electrodes the changes were minor, but basophilic and eosinophilic collagen fibres with no birefringence or with fine/coarse cross-striation respectively were seen. Even cells with 'vesicular nuclei' were seen on day 1 and 2 after the injury. The changes in the anode area showed resemblance to that of heat lesions (basophilic collagen fibres). Eosinophilic collagen fibres with fine densely spaced cross-striation in polarized light and 'vesicular nuclei' as well as collagen fibres with calcium salts were seen in the cathode lesions. It is concluded that the dermal changes in the cathode area are specific for electrical injury from day 1 to 14. However, earlier studies have demonstrated dermal changes specific for electrical injury at day 0 and the presence of calcified collagen fibres up to 2 months after injury. The dermal changes in anode lesions were non specific and could not be differentiated from those found in heat lesions. Alternating current lesions (50 Hz) were specific from day 1 to day 7, when the pointed electrode was used, but only in a few days when the energy was transferred via the 12-mm electrodes.     

Simultaneous observation of catecholamine, serotonin and their metabolites in incised skin wounds of guinea pig.

In order to examine the vital reaction in wounds, catecholamines, serotonin (5-HT) and their metabolites in the incised skin wounds of guinea pigs were analyzed simultaneously by high-performance liquid chromatography (HPLC) using electrochemical detection (ECD). The principal changes in the levels of these compounds in vital wounds were as follows: a considerable decrease in norepinephrine (NE) content was observed 12-24 h after injury which persisted to at least 7 days. 3,4-Dihydroxyphenylacetic acid (DOPAC) decreased slightly for up to 30 min and then showed no significant difference compared with postmortem levels. Epinephrine and dopamine were barely detected by the HPLC-ECD method employed. 5-HT concentrations which showed an increase up to 24 h showed maximum levels 800 microns from the wound edge at 10 and 30 min after injury. 5-Hydroxyindoleacetic acid (5-HIAA) was significantly higher than the postmortem level over almost the entire period of these experiments. A 5-HIAA content of at least twice the postmortem level was observed 800 microns from the wound edge of a 10-min-old vital wound. Therefore, 5-HIAA is a likely candidate as a new marker for evaluating the vital reaction in wounds. The vital characteristics of NE, DOPAC, 5-HIAA and 5-HT in 10-min-old wounds persisted for up to 12 h at room temperature after death. These results suggest that the HPLC-ECD method used here is very useful for simultaneous examination of the vital reaction in wounds from the earliest to the later stages of the wound-healing period.     

The effect of sodium hydroxide and hydrochloric acid on pig dermis. A light microscopic study

In order to compare the dermal changes after exposure to direct current (d.c.) with changes after influence of acid and base influence, the skin of fully anaesthetized Danish Landrace pigs were exposed to acid and basic solutions. Biopsies were obtained immediately after and up to day 7 after the injury. Collagen fibres with increased affinity for eosin and irregular cross-striation in polarized light together with shrunken cells with dark stained nuclei were found just beneath the epidermis immediately after application of 1 N HCl. Immediately after exposure to 1 N NaOH dispersed collagen fibres showed increased eosinophilia and a fine densely spaced cross-striation in polarized light and vesicular nuclei were present within dermal cells. During the following days a narrow demarcation zone of neutrophilic granulocytes separated the zone containing abnormal collagen fibres from normal tissue below. Calcified collagen fibres were not observed and no other abnormal histochemical reactions were present. It is concluded that the morphology of acid induced lesions and base induced lesions shows resemblance to the morphology of anode and cathode lesions, respectively, but not to heat lesions. The reason for not finding depositions of calcium salts on collagen fibres in skin exposed to basic solutions could be a non-optimal pH in the tissue or that other electrochemical processes than shift in pH are necessary for the calcification process.     

Electrical and thermal injuries in pig skin — Evaluated and compared by light microscopy

The morphology of pig skin after electrical (el) and thermal exposure was studied in order to find methods applicable for disclosing electrical torture.Biopsies from pig skin exposed 24 hours earlier to either heat or electrical current under general anesthesia were studied by light microscopy. The amount of energy used of either type ranged from about 6 to about 100 joule deposited on two circular areas of the skin measuring 12 mm in diameter.In sections stained with hematoxylin and eosin alterations were found in heat-influenced specimens following the administration of moderate and large doses of energy. Changes were observed in el-influenced specimens also after the administration of low amounts of energy, which did not lead to macroscopical changes in the skin. The two types of energy induced different patterns of alterations inside the epidermis. The most characteristic change following heat exposure was the presence of a granular or fibrillar eosinophilic cytoplasm and subepidermal clefts, while el-expoure often produced white homogeneous cytoplasm and shadowy nuclei (“white necrosis”) in the attached epidermis. The individual changes could be produced by both types of injury, but to a highly different degree. However, the alteration classified as “vesicular nuclei” was only observed in el-damaged skin. The dermis from the more severely injured skin of both groups showed a homogeneous appearance (“necrosis”). While the changes of epidermis and dermis in response to heat were diffusely distributed, the changes created by electrical injury were often present in segments. By electrical damage homogeneous areas with loss of stainability and shadowy nuclei were occasionally observed in sweat glands, hair sheaths and in vessel walls, structures which are suggested to serve as conductors for the electrical current. “Vesicular nuclei” were observed in similar structures.Some of the findings may be associated with differences in intensity of energy during exposure to heat and electricity. Furthermore, the existence of different biological patterns following the two types of exposure should be considered. The studies are being continued to elucidate these basic questions, and to study further the medical diagnostic potential of examining skin biopsies from tortured individuals.     

Sudden cardiac death: a comparative study of morphological, histochemical and biochemical methods.

The study deals with the comparison of morphological, histochemical and biochemical methods applied to the detection of myocardial infarction in 150 medico-legal autopsies performed at the Institute of Forensic Pathology in Copenhagen. The study also included an NBT (formazan) test of cardiac cross-sections, and light microscopy and fluorescence microscopy of acridine orange-stained specimens from four different sites of the cardiac musculature. Specimens of myocardium from the same four sites and pericardial fluid were analysed biochemically at the Institute of Legal Medicine in Granada. The K+/Na+ ratio was determined in the myocardial tissue and total creatine phosphokinase activity, creatine phosphokinase isoenzymes (MM, MB and BB) and myoglobin were assayed in pericardial fluid. When the results from Copenhagen and Granada were compared, there was absolute concordance in 96 cases, discrepancy in 53 and one case was inconclusive. After studying the circumstances of death, the number of discrepancies were reduced to 20, so that concordance was reached in 86% of all the cases. The results show that the combination of different methods leads to a diagnosis of myocardial infarction in far more cases than with morphological or biochemical methods alone.     

A soft-tissue calcification: differential diagnosis and pathogenesis

An autopsy of a 72-year-old white male revealed a 30.5 x 5.1 cm vertically aligned heterotopic ossification just deep to a 30.5 cm midline abdominal scar. The ossified mass was determined to be a heterotopic ossification or myostitis ossificans (MO) traumatica resulting from an abdominal surgical incision during life. While, MO traumatica is relatively common accounting for roughly 60-75% of patients with soft-tissue ossification, heterotopic ossification of abdominal incisions are relatively rare and thus infrequently reported. This article details the manifestation of this relatively large heterotopic bone and provides a comprehensive review of the literature and pathogenesis of this unusual ossification. A review of the English literature from 1920 to the present produced only a handful of articles for a total of 185 reported cases. All had bone formed within vertical incisions, usually within 1 year of surgery, and 89% were males. Knowledge of this phenomenon and the variable size at presentation is useful to both the autopsy pathologist and the anthropologist in generating a diagnosis for abnormal calcifications.     

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.     

An experimental study of powder tattooing of the skin.

Test firings were conducted on specially prepared live rabbits to determine the approximate maximum ranges at which powder tattooing occurs for different forms of gunpowder. For .38 caliber, powder tattooing from cartridges loaded with flake powder disappears at a range of 18 to 24 in. (0.4 to 0.6 m). Powder tattooing with flattened ball powder extends to 36 in. (0.9 m), while that due to ball powder extends to 48 in. (1.2m) of range. In .22 caliber, powder tattooing was observed out to 24 in. (0.6 m) with flake powder and 18 in. (0.4 m) with flattened ball. Attempts to reproduce the animal powder tattoo patterns on paper revealed that the paper patterns are consistent with skin tattoo patterns only up to 18 in (0.4 m) of range.     

失血即刻死亡心肌超微结构,组织化学及免疫组化研究

本研究应用电镜、组织化学、免疫组化及形态计量分析等方法和技术，观察失血即刻死亡时家兔心肌超微结构、琥珀酸脱氢酶（ＳＤＨ）活性、肌红蛋白（Ｍｂ）脱失的变化特点。结果发现，失血即刻死亡时家兔心肌细胞轻度水肿，肌原纤维普遍强度收缩，肌节缩短，Ｚ线增粗，心肌细胞内ＳＤＨ活性明显下降，Ｍｂ轻度局灶性脱失．     

A validation study of mRNA markers for skin cell identification

The objectives of this study were to develop and optimize a multiplex of three skin specific gene markers; loricrin (LOR), corneodesmosin (CDSN) and keratin 9 (KRT9) and 1 house-keeping marker, β-actin (ACTB) using an endpoint PCR assay to analyze expression data from a range of relevant samples. Marker specificity and suitability were evaluated for their inclusion in future forensic casework. The presence of the three skin mRNA markers was successfully confirmed from swabs of human skin obtained from 20 individuals at each of 6 different body sites (forehead, neck, arm, palm, leg and sole). Significant variation was observed in the relative expression of the three genes across the body sites, with some individuals consistently failing to express one or more of the targets. Inter-individual variation was also evident. Accordingly, these markers must be used with caution in the identification of skin in forensic samples.     

A new staining method for constriction marks in skin.

A modified Poley's acid fuchsin-methyl green stain was used to demonstrate ligature marks in tissues taken at autopsy. This stain was compared in 30 cases with haematoxylin-eosin, Mallory's trichrome and Ogata's picro-indigocarmine stains. Using the modified Poley method, it was possible to demonstrate the compression mark in corpses even when post-mortem changes were advanced. The method was found useful in evaluating the cases when the force used was minimal or when the mark was atypical using the usual haematoxylin-eosin method.     

Ultrastructural changes in dermal pig skin after exposure to heat and electric energy and acid and basic solutions

In order to describe the ultrastructure of the histopathological changes in dermis after exposure to electrical energy, heat energy and acid and basic solutions the skin of fully anaesthetized Danish Landrace pigs were exposed to direct current, heat (80 degrees C and 450 degrees C) and acid and basic solutions. Biopsies were obtained immediately after the exposure from all types of injury. Biopsies from the cathode areas biopsies were also taken on day 1 and day 2.5 in order to describe the initial calcium deposits. Homogeneous collagen fibres without any birefringence from heat exposed areas were ultrastructurally composed of filamentous materials. Collagen fibres with fine densely spaced cross-striation from cathode areas and areas exposed to basic solutions were shown ultrastructurally to consist of parallelly arranged collagen fibrils with regular waves. It is concluded that the cross-striation of the collagen fibres observed in polarized light are due to a periodic change in the orientation of the fibres seen as waves of the fibres. The ultrastructure of dermal cells were similar to that of epidermal cells following the different types of influence. Characteristically the nuclei were condensed following heat and more electron-lucent following direct current (d.c.) and acid and basic solutions. In cathode areas and areas influenced by basic solutions the electron-lucent nuclei contained fine fibrils. The ultrastructural study supports the suggestion from light microscopic studies that the morphology of anode and cathode lesions shows resemblance to acid induced and basic induced lesions, respectively. Apatite crystals were observed on day 2.5 at the periphery of the collagen fibrils and in the matrix of elastic fibres.     

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。     

A study on the vital reaction in wounded skin: simultaneous determination of histamine and polyamines in injured rat skin by high-performance liquid chromatography

This paper describes a modified method of simultaneous quantitative determination of histamine and polyamines (putrescine, cadaverine, spermidine and spermine) in incised skin wounds of rats using high-performance liquid chromatography (HPLC) with a strong-cation exchange column, shim-pack ISC-05/S0504P, employing a linear gradient of 0.7-2.5 M sodium chloride. There was scarcely any change in the histamine content of the vital wounds throughout the one week experimental period, although content decreased slightly in 1-h-old wounds. On the other hand, concentrations of putrescine and spermidine increased suddenly 12 h after wounding, and spermine content increased slightly in 4-day-old wounds. There was no post-mortem change in the histamine, spermidine and spermine contents of vital wounds allowed to stand at 25 degrees C up to 24 h after death. Based on these results, this HPLC method may be useful for the determination of wound age during the period of healing.     

A preliminary study of skin electrical injury with computerized image analysis

This paper reports the application of computerized image analysis to a quantitative study of skin electrical injury in order to provide an objective and quantitative standard for identifying the electrical mark. The differences between antemortem and postmortem electrical injuries were also studied. In normal and electrically-injured human skin, the long/short axes ratio of nuclei were measured. The mean of epithelial basal cells was 1.4344 and 5.9325, respectively, the mean of hair follicle cells was 1.6193 and 4.5988, respectively, and the mean of capillary endothelial cells was 4.0229 and 4.3593, respectively. In rat specimens, the long/short axes ratio of nuclei of normal skin, at 15 and 5 min ante-mortem and at 5 min postmortem injury, the mean epithelial basal cells was 1.4124, 4.5417, 5.2282 and 5.0447, respectively. The mean of hair follicle cells was 1.4140, 4.4863, 4.1146 and 4.4522, respectively, while the mean of capillary endothelial cells was 2.8398, 3.7514, 3.6159 and 3.6977, respectively. The results indicate that the differences between electrical injuries and normal skin with respect to the ratios of long/short axes of the epithelial basal cell nuclei and hair follicle cell nuclei are of remarkable significance. On the other hand, no significant difference could be found between antemortem and postmortem injuries, nor between electrical injury and normal skin, concerning the long/short axes ratios of capillary endothelial cell nuclei. This result provides a preliminary objective standard for the changes of electrical skin injury.