Muscular Hemorrhages Around the Scapula Provide Insight on the Manner of Asphyxia: A Preliminary Study.

ABSTRACT: Muscular hemorrhages around the scapula that are caused by upper extremity motion are rarely reported in cases other than drowning. We examined differences in the frequency of muscular hemorrhages around the scapula and stratified them by the cause of death. Muscular hemorrhages were mostly noted in cases of drowning (118/185, 63.8%), followed by cases of asphyxia (23/44, 52.3%). In addition, muscular hemorrhages around the scapula were found in cases of ligature strangulation (8/11, 72.7%), manual strangulation (2/3, 66.7%), choking (11/14, 78.6%), and traumatic asphyxia (2/2, 100%). Muscular hemorrhages were not found in cases of hanging or environmental suffocation, possibly because of the short time interval preceding the loss of consciousness. The distribution of muscular hemorrhages was similar in choking and drowning cases. Muscular hemorrhages due to strangulation were mainly unilateral, whereas those due to choking and drowning were mainly bilateral. During all types of asphyxia, muscular hemorrhages around the scapula were considered to be the result of conscious, active upper extremity motion. Because the frequency and laterality of muscular hemorrhages around the scapula differed based on the type of asphyxia, our findings provide insights into the manner of asphyxia that could be used to aid in the identification of homicidal hangings.

A Case of Personal Identification Via Postmortem Computed Tomography Confirmation of Aphakic Eyes.

Postmortem computed tomography (PMCT) is used commonly in forensic medicine. Postmortem computed tomography of the head provides information on the eyes and orbits and may reveal intraocular abnormalities. We present a case in which the identity of a deceased man was confirmed by the presence of aphakic eyes detected on PMCT. A decomposed body was found in a house and suspected to be a man in his 40s who lived alone. Autopsy identified pontine hemorrhage as the cause of death. Although signs of previous dental treatment were evident, the storage period of the householder's dental records had expired. He had no family members to provide DNA for a comparative DNA analysis. Postmortem computed tomography before autopsy revealed aphakia (ie, the absence of eye lenses) suggestive of previous ocular surgery. His medical records revealed that he had undergone ocular surgery for secondary glaucoma due to uveitis, which had resulted in artificial aphakia. Peripheral iridectomy scars fully matched the findings in his medical records, thus identifying the body. The unusual finding of artificial aphakia in a man in his 40s facilitated the personal identification in this case. In conclusion, PMCT provides additional information, and the correct interpretation of intraocular PMCT findings by forensic pathologists is crucial.

Zebrafish (Danio rerio) as a model to visualize infection dynamics of Vibrio anguillarum following intraperitoneal injection and bath exposure.

Vaccine development is important for sustainable fish farming and novel vaccines need to be efficacy tested before release to the market. Challenge of fish with the pathogen towards which the vaccine has been produced can be conducted either by external exposure though bathing or cohabitation, or by bypassing the mucosa through injection. The latter approach is often preferred since it is easier to control than the former. However, injection is not a very natural route of infection, and the bypass of the mucosa may result in a different efficacy profile of experimental fish compared to farmed fish, for which the vaccines are targeted. The zebrafish is by now a well established practical vertebrate model species due in part to its size and ease of maintenance and genetic manipulation. Here we use zebrafish as a model to visualize and compare the development of infection of Vibrio anguillarum on and in the fish following injection or bathing. Injection of 103 bacteria per fish resulted in approximately 50% mortality by day 4 post-injection. Similar mortality levels were reached in the other group by bathing in 1.25 × 109 bacteria for 1 min. The spreading of bacteria was followed for the first 24 h after injection/bathing by immunohistochemistry and optical projection tomography. The tissues and organs where bacteria were detected differed significantly as a result of time as well as treatment. In the bath group, bacteria were initially found on external surfaces including gut. After 24 h V. anguillarum still persisted in gut but had now also spread to the blood. In the injection group bacteria were found in the blood throughout all sampling times, as well as in the hypodermis and body cavity at most sampling times.

Characterization of a specific monoclonal antibody against immunoglobulin light kappa/L1 chain in olive flounder (Paralichthys olivaceus).

Immunoglobulins (Ig) are heterodimeric proteins that play critical roles in the adaptive immune system of vertebrates. Because of their plasticity, teleostean Igs are more diverse, and thus do not conform to mammalian classifications. Because of this, mammalian-based Ig cell markers cannot be used successfully to study immune responses in fish. There is therefore a need to produce Ig-specific cell markers for fish. Here, we attempted to identify the specific isotype detected by an Ig light chain-specific monoclonal antibody (anti-olive flounder IgL-mAb: M7C3-4) that we had previously produced [11]. Three newly identified sequences of the Ig light chain from olive flounder were classified according to their isotypes. Subsequent analyses revealed that M7C3-4 was able to specifically detect lymphocytes expressing one of the κ chains (Igκ-a) in olive flounder. Interestingly, Igκ-a+ B cells were more abundant in spleen and trunk-kidney than in peripheral blood, indicating a distribution different from that of IgM+ B cells. Our work reveals interesting aspects of B cell distribution and differentiation, and may aid in the production of suitable and effective cell markers for olive flounder.

Transcription analysis of two Eomesodermin genes in lymphocyte subsets of two teleost species.

Eomesodermin (Eomes), a T-box transcription factor, is a key molecule associated with function and differentiation of CD8(+) T cells and NK cells. Previously, two teleost Eomes genes (Eomes-a and -b), which are located on different chromosomes, were identified and shown to be expressed in zebrafish lymphocytes. For the present study, we identified these genes in rainbow trout and ginbuna crucian carp. Deduced Eomes-a and -b amino acid sequences in both fish species contain a highly conserved T-box DNA binding domain. In RT-PCR, both Eomes transcripts were readily detectable in a variety of tissues in rainbow trout and ginbuna. The high expression of Eomes-a and -b in brain and ovary suggests involvement in neurogenesis and oogenesis, respectively, while their expression in lymphoid tissues presumably is associated with immune functions. Investigation of separated lymphocyte populations from pronephros indicated that both Eomes-a and -b transcripts were few or absent in IgM(+) lymphocytes, while relatively abundant in IgM(-)/CD8α(+) and IgM(-)/CD8α(-) populations. Moreover, we sorted trout CD8α(+) lymphocytes from mucosal and non-mucosal lymphoid tissues and compared the expression profiles of Eomes-a and -b with those of other T cell-related transcription factor genes (GATA-3, T-bet and Runx3), a Th1 cytokine gene (IFN-γ) and a Th2 cytokine gene (IL-4/13A). Interestingly, the tissue distribution of Eomes-a/b, T-bet, and Runx3 versus IFN-γ transcripts did not reveal simple correlations, suggesting tissue-specific properties of CD8α(+) lymphocytes and/or multiple modes that drive IFN-γ expressions.

Age estimation using postmortem computed tomography-based Hounsfield unit values of the palate and mandibular condyle and the Eichner classification.

Age estimation is important in forensic investigations of unidentified human remains. This study assessed the correlation between age and Hounsfield unit (HU) values of the palate and mandibular condyle based on postmortem computed tomography (CT) and analyzed the influence of occlusal support in developing an age estimation method for Japanese individuals, including older adults. The sample consisted of a training dataset (357 cadavers) and a validation dataset (300 cadavers) that underwent postmortem CT. Three measurements were selected: the respective HU values of the palate and mandibular condyle and the Eichner classification. The correlation coefficients between age and HU values were also evaluated. Multiple stepwise regression analysis was performed to evaluate the significance of four parameters (sex, respective HU values of the palate and mandibular condyle, and the Eichner classification) for age estimation and to determine the best age estimation formula. In the validation tests, inaccuracy and bias were calculated for the groups aged ≥65 or <65 years. Significant correlations between age and HU values of the palate and mandibular condyle were observed, regardless of sex. In multiple stepwise regression analysis, all variables except sex were significantly correlated with age. The age estimation formula from the regression analysis was useful, and the validation test exhibited high accuracy, especially in older adults. The HU values of the palate and mandibular condyle and the Eichner classification are useful for age estimation in Japanese individuals.

Variable domain antibodies specific for viral hemorrhagic septicemia virus (VHSV) selected from a randomized IgNAR phage display library.

Phage display libraries are used to screen for nucleotide sequences that encode immunoglobulin variable (V) regions that are specific for a target antigen. We previously constructed an immunoglobulin new antigen receptor (IgNAR) phage display library. Here we used this library to obtain an IgNAR V region that is specific for viral hemorrhagic septicemia virus (VHSV). A phage clone (clone 653) was found to be specific for VHSV by the biopanning method. The V region of clone 653 was used to construct a 6 × His tagged recombinant IgNAR-653 V protein (rIgNAR-653) using the Escherichia coli pET system. The rIgNAR-653 protein bound specifically to VHSV, confirming its activity.

Characterization and functional analysis of two PKR genes in fugu (Takifugu rubripes).

PKR (protein kinase R) is a serine-threonine kinase that inhibits protein synthesis by the phosphorylation of the eukaryotic translation initiation factor 2-alpha (eIF2α), and activates NFκB by inducing NFκB-inducing kinase and IκB (inhibitor of NFκB) kinase. This can lead to antiviral and anti-proliferative effects. In this study, the complete sequence and organization of two fugu PKR genes (fPKRs) were determined by in silico analysis and conventional PCR. The full-length fPKR1 and fPKR2 genes were 3832 bp and 4325 bp, which encoded 523 and 492 amino acids, respectively. Both encoded two dsRNA binding domains and a Serine/Threonine protein kinase domain, and showed very high similarity to green spotted puffer PKRs. Gene expression of the two fPKRs was measured by quantitative real-time PCR on tissue samples from healthy fish and peripheral blood leukocytes stimulated with polyinosinic:polycytidylic acid (PolyI:C) or lipopolysaccharides (LPS). The fPKRs were highly expressed in the skin and fPKR2 was significantly induced in PBLs by PolyI:C but not by LPS. The fPKRs inhibited translation of a luciferase reporter gene in a dose-dependent manner and induced transcriptional activity of a mammalian NFκB luciferase reporter. These results demonstrate that two PKRs in a single species can both be independently, but not equally, functional and support the hypothesis that fish PKRs have roles in the innate immune response similar to those of mammalian PKRs.

Recombinant interferon-γ activates immune responses against Edwardsiella tarda infection in the olive flounder, Paralichthys olivaceus.

Interferon gamma (IFN-γ) is a cytokine that plays a very important role in defining Th1 immune response in all vertebrates. In this study, recombinant IFN-γ (rIFN-γ) from the olive flounder (Paralichthys olivaceus) was produced in an Escherichia coli system using a pET expression vector. Stimulation of whole kidney leukocytes (immune-related cells) in vitro with the resulting rIFN-γ significantly induced the gene expression of interleukin-1ß (IL-1ß), signal transducer and activator of transcription 1 (STAT1), CXCL13-like chemokine (CXCL13), and IFN-γ. rIFN-γ also weakly induced the expression of IL-1ß, tumor necrosis factor-α (TNF-α), CXCL13, and IFN-γ in olive flounder-derived HINAE (non-immune) cells. The effects of rIFN-γ against Edwardsiella tarda infection in vivo were assessed by intraperitoneally injecting a mixture of rIFN-γ (100 ng) and E. tarda (1 × 10(5) CFU/ml) into the olive flounder. The survival rate in the rIFN-γ-injected group was 60% compared to 0% in the group treated with E. tarda only, demonstrating that olive flounder IFN-γ is effective in reinforcing immune responses and preventing against edwardsiellosis.

Evolutional conservation of molecular structure and antiviral function of a viral RNA receptor, LGP2, in Japanese flounder, Paralichthys olivaceus.

LGP2 is an important intracellular receptor that recognizes viral RNAs in innate immunity. To understand the mechanism of viral RNA recognition, we cloned an LGP2 cDNA and gene in Japanese flounder (Paralichthys olivaceus). Viral hemorrhagic septicemia virus-induced expressions of LGP2 mRNA were evaluated in vivo and in vitro by quantitative real-time PCR (Q-PCR) using primers based on the clone sequences. The expression of LGP2 mRNA in the kidney dramatically increased at 3 d postinfection. The expression of LGP2 mRNA also increased in the head kidney leukocytes stimulated with artificial dsRNA (polyinosin-polycytidylic acid) in vitro. To evaluate the antiviral activity of the flounder LGP2, three expression constructs containing pcDNA4-LGP2 (full-length), pcDNA4-LGP2ΔRD (regulatory domain deleted), and pcDNA4-Empty (as a negative control) were transfected into the hirame (flounder) natural embryo (hirame natural embryo) cell line. Forty-eight hours after transfection, the transfected cells were infected with ssRNA viruses, viral hemorrhagic septicemia virus, or hirame rhabdovirus. The cytopathic effects of the viruses were delayed by the overexpression of Japanese flounder LGP2. The Q-PCR demonstrated that mRNA expression levels of type I IFN and IFN-inducible genes (Mx and ISG15) in the hirame natural embryo cells overexpressing LGP2 were increased by polyinosin-polycytidylic acid and viral infections. These results suggest that Japanese flounder LGP2 plays an important role in the recognition of both viral ssRNA and dsRNA to induce the antiviral activity by the production of IFN-stimulated proteins.

A forensic autopsy case: Sudden unexpected death due to cardiac inflammatory myofibroblastic tumor.

We report an autopsy case of a 25-year-old man with no medical history who died suddenly in an Internet cafe. He was found in cardiorespiratory arrest and did not respond to cardiopulmonary resuscitation. Traumatic lesions were not observed on his body. An autopsy was performed to investigate the cause of death. Upon examination, we discovered a heart tumor that infiltrated from the outside wall to the outflow tract of the left ventricle. Left ventricular outflow tract obstruction due to a cardiac tumor was considered the mechanism of death. Histological examination identified an inflammatory myofibroblastic tumor (IMT). The final diagnosis was death secondary to circulatory failure due to a cardiac IMT. Additionally, a cardiac tumor was diagnosed using post-mortem computed tomography. Only few cases of sudden unexpected death due to cardiac IMT have been reported; we report this case along with a review of the literature.

Molecular cloning and antiviral activity of IFN-ß promoter stimulator-1 (IPS-1) gene in Japanese flounder, Paralichthys olivaceus.

The mitochondrial adaptor, IFN-ß promoter stimulator-1 (IPS-1), also known as MAVS/VISA/Cardif, plays a key role in the signal transduction of the RIG-1/MDA5 pathway to induce the production of interferons (IFNs) and other cytokines. In the present study, Japanese flounder (Paralichthys olivaceus) IPS-1 cDNA was cloned from Japanese flounder spleen using PCR-based methods. The full-length cDNA has 2235 nucleotides and encodes a polypeptide of 641 amino acids. The putative Japanese flounder IPS-1 protein contains an N-terminal CARD-like domain, a central proline-rich domain, a C-terminal transmembrane domain, and exhibits similarity to other teleost counterparts ranging from 20% to 34%. Semi-quantitative RT-PCR showed that Japanese flounder IPS-1 mRNA was expressed in all tissues examined. The expression level of flounder IPS-1 gene was unchanged in viral hemorrhagic septicemia virus (VHSV)-infected kidney as measured by quantitative real-time PCR (Q-PCR). In addition, Japanese flounder IPS-1-overexpressing cells were protected against hirame rhabdovirus (HIRRV) and VHSV infection as manifested by the delayed appearance of cytopathic effect (CPE) and decreased viral titers. Expression of IFN-inducible genes including Mx, ISG15 and IRF3 were also induced in the IPS-1-overexpressing cells. These results suggest that Japanese flounder IPS-1 is involved in the antiviral immunity as a one of the adaptors in fish IFN-activation pathway.

Spectrophotometric evaluation of the age of bruises in children: measuring changes in bruise color as an indicator of child physical abuse.

Physical abuse of children is a severe social problem and is usually identified by the presence of bruises of various ages. The visual appearance of bruises is widely used to identify victims of abuse. Therefore, to objectively evaluate the age of bruises, we used a spectrophotometer to examine 86 bruises that occurred accidentally in healthy child volunteers, with consent from appropriate guardians. The bruise color was measured using a spectrophotometer and plotted using the CIE-L*a*b* color system, a method that expresses color numerically. The differences [Delta] in L* (lightness), a* (red and green content) and b* (yellow and blue content) color values relative to neighboring healthy/unbruised skin were measured for 7-10 days until the bruise disappeared. A characteristic pattern was observed in 21 bruises; DeltaL* increased from the negative peak and returned to baseline, Deltaa* decreased from the positive peak to baseline, and Deltab* increased above baseline and then slowly returned to baseline. The pattern of these color changes could be classified into three phases according to the time between bruising and the peak values for DeltaL* (negative peak, 38.9 +/- 19.5 hours), Deltaa* (positive peak, 37.6 +/- 21.7 hours), and Deltab* (negative and positive peak, 43.5 +/- 18.7 and 132.6 +/- 40.4 hours). Thus, spectrophotometric measurement of the color of bruises is helpful to estimate the approximate age of bruises and to distinguish between old and new bruises. This objective method could be introduced to clinical practice and social care to evaluate possible cases of child abuse.

Back hemorrhage in bath-related deaths: Insights into the mechanism of bath-related deaths.

Forensic pathologists often encounter difficulties while diagnosing bath-related deaths owing to a lack of specific findings for determining the cause. This study reports the characteristic findings noted during autopsy associated with bath-related deaths. The subjects included individuals found deceased in water-filled bathtubs. Originally, a "bathtub death" was defined as a case of drowning in a bathtub without a known cause despite complete investigation including a complete autopsy and examination of the death scene. We also excluded cases with ethanol and/or high drug concentrations in the blood from "bathtub death" cases. Muscular hemorrhages around the scapula were the most common in cases of accidental drowning (72.7%). The frequency of muscular hemorrhages around the scapula was low in cases involving bathtub deaths (11.1%) and natural disease. Subcutaneous hemorrhages in the back were the most frequent in cases of bathtub death (88.9%), followed by accidental drowning (81.8%). The frequency of subcutaneous hemorrhages in the back was low in cases involving suicide and natural disease. The presence of subcutaneous hemorrhages in the back without muscular hemorrhages around the scapula were strongly associated with bathtub deaths (Fisher's exact test, P < 0.0001; sensitivity, 0.84; specificity, 0.91). Subcutaneous hemorrhages were the most frequent in the waist (68.8%), followed by the upper back (50%). Subcutaneous hemorrhages in the back without muscular hemorrhages around the scapula indicated that the deceased had hit their back on falling from a standing position after experiencing disturbances of consciousness. We found the occurrence of orthostatic hypotension while getting out of the bathtub to be the most likely cause for these autopsy findings. Subcutaneous hemorrhages in the back without muscular hemorrhages around the scapula is a characteristic finding of "bathtub deaths". Although this was a preliminary study, the presence of this finding may aid in clarifying the mechanism of bath-related deaths.

Citrus flavonoids, ß-Glucan and organic acid feed additives decrease relative risk during Yersinia ruckeri O1 biotype 2 infection of rainbow trout (Oncorhynchus mykiss).

Whether through direct supplementation of bacteria or by prebiotic supplementation thought to favour subsets of bacteria, modulation of gut microbiota constitutes an important and promising alternative to the use of prophylactic and growth promoting antibiotics in worldwide aquaculture. We fed a commercial base feed, alone or supplemented with either proprietary ß-glucan, ß-glucan and organic acids, citrus flavonoid or yeast cell wall supplements, to rainbow trout over a period of four weeks. Fish from each feed group were then subjected to experimental, waterborne infection with Yersinia ruckeri O1 biotype 2. Following experimental feeding, the ß-glucan and organic acids supplemented group showed significantly improved feed conversion and lipid efficiency ratios. Furthermore, the ß-glucan, ß-glucan and organic acids and citrus flavonoid supplements proved to significantly reduce the risk of mortality in rainbow trout during experimental infection as shown by hazard ratio analysis. Resulting in 33.2%, 30.6% and 30.5% reduction in risk relative to the non-supplemented base feed, respectively, these three supplements show a promising potential either as stand-alone feed supplements, or as components in complex feed formulations.

Synbiotic feed supplementation significantly improves lipid utilization and shows discrete effects on disease resistance in rainbow trout (Oncorhynchus mykiss).

Enteric redmouth disease caused by the bacterial pathogen Yersinia ruckeri is the main reason for antimicrobial prescription, and a cause of substantial economic losses and decreased animal welfare in aquaculture. Given the importance of the intestinal microbiota in digestion and disease, our aim was to investigate whether synbiotic feed supplementation strategies could improve feed performance and disease resistance. Four experimental synbiotic feeds formulated with pre- and probiotics were tested against a commercially available probiotic control feed. Each experimental feed was evaluated for feed performance, effects on gross as well as intestinal morphometrics, and finally their effect on resistance against a waterborne experimental infection with Yersinia ruckeri serotype O1, biotype 2. While co-supplementing Pediococcus acidilactici with citrus flavonoids or bacterial paraprobiotics significantly improved utilization of feed lipid content relative to the control group, a decrease in lipid utilization was observed for feeds that combined P. acidilactici with yeast paraprobiotics. No significant improvements on disease resistance were observed. Still, synbiotic formulations including P. acidilactici led to reduced risks relative to that of the control group, while an increased relative risk was observed for a Bacillus-based formulation. In conclusion, two of the synbiotic supplements significantly improved lipid utilization and contributed to minor increases in disease resistance.

Muscular hemorrhages around the scapula resulting from excessive upper extremity motion in cases of fatal drowning: autopsy findings for insights on manner of death.

Muscular hemorrhages around the scapula are frequently found in fatal drowning cases without injuries in the upper back at time of autopsy. The present study investigated the frequency of muscular hemorrhages around the scapula and determined the mechanism responsible for this phenomenon. Muscular hemorrhages around the scapula were found in 104 of 164 (63.4%) bodies assessed. Hemorrhage in the infraspinatus muscle was most common, followed by the supraspinatus muscle. These muscular hemorrhages were not associated with upper extremity injuries and were most frequently found in accidental drowning cases (78.7%), followed by cases of suicide (56.0%), and in natural disease prior to drowning (19.0%). We examined muscular hemorrhage around the scapula and cervical injuries that restricted the active motion of upper extremities in drowning cases. The vertebral level of cervical injuries were related to muscular hemorrhages around the scapula. These results suggested that muscular hemorrhages around the scapula were not a result of agonal convulsions but were caused by consciously active excessive motion of the upper extremities while drowning. Investigations of the muscular hemorrhages around the scapula can provide insights towards the manner of fatal drowning.

Injury patterns of fatal bear attacks in Japan: A description of seven cases.

In recent years, the number of bear attacks has risen in Akita prefecture, Japan. Here, we present the injury patterns of seven fatal bear attacks, and discuss the implication of these findings. We included five cases of Asiatic black bear attacks and two cases of Ezo brown bear attacks. In all cases, the injuries, 2-5 parallel linear lacerations with severe hemorrhaging and decollement, were mainly located on the upper body. These injuries were thought to be fatal as, upon a first encounter, bears often stand and first attack the victim's head and face using their claws. Four lacerations were located at the vertex of the trapezoid in all cases, without severe hemorrhaging on the neck, extremities, or around the antemortem injuries. These injuries were thought to be bite marks incurred by the bears' four large canines, mainly occurring postmortem during the process of predation. These findings differed from those of fatal biting around the neck by other animals such as lions, mountain lions, or large-sized dogs. Further, laceration with avulsion of the skin was found in the inguinal region, without severe hemorrhaging. In some cases, the intestine had been removed from the inguinal injury for predation. In conclusion, the injuries of bear attacks are different from those caused by other animals, owing to the characteristics of bears. By investigating the injuries caused by fatal bear attacks, we can better understand the patterns of such injuries. Especially, the diameter between the canines is sometimes useful to estimate the size and the number of offending bears.

Visualization of old bruises in children: Use of violet light to record long-term bruises.

When a child consultation center evaluates abused children, evidence of the abuse must be documented. Children who have suffered physical abuse often have bruises, which cannot be confirmed by visualization when the bruise has healed. In forensics, a method to confirm an old bruise by ultraviolet radiation is possible. However, long-term ultraviolet exposure can be harmful. In this study, we observed 15 bruises on healthy volunteer children using four kinds of light sources, including ultraviolet radiation, over time. The violet light source enabled observation of a bruise for a longer time than ultraviolet radiation. Although other studies have shown that violet light is superior for enhancing bruises, this is the first report to evaluate data concerning the ability to identify bruises over time in living children. These results might help to identify evidence of past violence suffered by children.

Pathological demonstration of rapid involvement into the subcutaneous tissue in a case of fatal hydrofluoric acid burns.

We report an autopsy case of a man who suffered accidental chemical burns following exposure to 60% hydrofluoric acid. The extent of the burns covered about 30% of his body surface, and cardiopulmonary arrest occurred about 30min after the exposure. At autopsy, the skin of the affected area showed greenish gray or black coloring with thin circumferential erythema, and this discoloration extended as far as the periosteum of the skull. However, such discoloration was not found on the mucosa of the airway or the gastrointestinal tract. Microscopically, severe liquefactive necrosis was already evident on the skin. Elastic fibers within the dermis were completely lost, and the entire wall of large vessels within the subcutaneous layer was already severely affected. Blood analysis in the emergency room showed hypocalcemia, and the levels of fluoride ions in the postmortem blood and urine showed extremely high values. However, fewer fluoride ions were detected from the lung tissue. The present case suggests that the hydrofluoric acid had immediately penetrated down into the deep layer of the skin, thereby involving the large vessels present within the subcutaneous layer. These pathological findings of the skin seen in the present case explain the mechanism behind the rapid dissemination of fluoride ions which entered the bloodstream from damaged arteries, resulting in the development of acute toxicity.