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.

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.

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.

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.

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.

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.

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.

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.

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.

An autopsy case of pneumococcal Waterhouse-Friderichsen syndrome with possible functional asplenia/hyposplenia.

We report an autopsy case of rapid progressive Waterhouse-Friderichsen syndrome (WFS) associated with Streptococcus pneumonia infection in a previously healthy man. Although he once visited a hospital about 6 hours before death, the both physical and serological examination did not show any sign of overwhelming infection. Autopsy showed massive adrenal hemorrhage without inflammation, and showed proliferation of gram positive cocci and microthrombosis in the vessels of many organs. The pathological change of respiratory tract was extremely minimal. Size and weight of the spleen possible decreased than normal. However, histological examination showed that obscuration of germinal center and decreasing the immunological cells of mantle and marginal zone. Immunohisitochemically, marked decreasing the marginal zone macrophages, which are positive for specific intercellular adhesion molecule grabbing nonintegrin receptor-1 (SIGN-R1) and macrophage receptor with collagenous structure (MARCO), were decreased comparing with age-matched control case. Polymerase chain reaction (PCR) assay using each DNA, extraction from formalin-fixed paraffin-embedded specimen (FFPE) samples of lung, adrenal gland, heart, spleen, and kidney showed positive the ply gene and the lytA gene specific for Streptococcus pneumonia. Present case showed possible acquired atrophy of spleen, especially decreasing marginal zone macrophage may correlate with rapid progression of sepsis of Streptococcus pneumonia with massive adrenal hemorrhage. In addition, present case showed the usefulness of PCR using FFPE for the postmortem diagnosis of WFS.

Detection of carbon monoxide poisoning that occurred before a house fire in three cases.

In our institutes, we perform a quantitative evaluation of volatile hydrocarbons in post-mortem blood in all fatal fire-related cases using headspace gas chromatography mass spectrometry. We previously reported that benzene concentrations in the blood were positively correlated with carbon monoxide-hemoglobin (CO-Hb) concentrations in fire-related deaths. Here, we present 3 cases in which benzene concentrations in the blood were not correlated with CO-Hb concentrations. A high CO-Hb concentration without a hydrocarbon component, such as benzene, indicates that the deceased inhaled carbon monoxide that was not related to the smoke from the fire. Comparing volatile hydrocarbons with CO-Hb concentrations can provide more information about the circumstances surrounding fire-related deaths. We are currently convinced that this is the best method to detect if carbon monoxide poisoning occurred before a house fire started.

Global 3D imaging of Yersinia ruckeri bacterin uptake in rainbow trout fry.

Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM) in rainbow trout, and the first commercially available fish vaccine was an immersion vaccine against ERM consisting of Y. ruckeri bacterin. The ERM immersion vaccine has been successfully used in aquaculture farming of salmonids for more than 35 years. The gills and the gastrointestinal (GI) tract are believed to be the portals of antigen uptake during waterborne vaccination against ERM; however, the actual sites of bacterin uptake are only partly understood. In order to obtain insight into bacterin uptake during waterborne vaccination, optical projection tomography (OPT) together with immunohistochemistry (IHC) was applied to visualize bacterin uptake and processing in whole rainbow trout fry. Visualization by OPT revealed that the bacterin was initially taken up via gill lamellae from within 30 seconds post vaccination. Later, bacterin uptake was detected on other mucosal surfaces such as skin and olfactory bulb from 5 to 30 minutes post vaccination. The GI tract was found to be filled with a complex of bacterin and mucus at 3 hours post vaccination and the bacterin remained in the GI tract for at least 24 hours. Large amounts of bacterin were present in the blood, and an accumulation of bacterin was found in filtering lymphoid organs such as spleen and trunk kidney where the bacterin accumulates 24 hours post vaccination as demonstrated by OPT and IHC. These results suggest that bacterin is taken up via the gill epithelium in the earliest phases of the bath exposure and from the GI tract in the later phase. The bacterin then enters the blood circulatory system, after which it is filtered by spleen and trunk kidney, before finally accumulating in lymphoid organs where adaptive immunity against ERM is likely to develop.

Examination of postmortem retinal folds: A non-invasive study.

The postmortem retinal fold has been previously documented, but its mechanism of formation is not known. All previous studies of the fold involved invasive techniques and the postmortem ocular fundus has yet to be non-invasively examined. Our study used the non-invasive techniques of monocular indirect ophthalmoscopy and ocular echography to examine 79 postmortem eyes of 42 bodies. We examined whether the postmortem retinal fold was associated with postmortem time, position, and/or age. Age was significantly associated with postmortem retinal fold formation (Mann-Whitney U test, P = 0.013), which led us to examine the effect of posterior vitreous detachment (PVD) on retinal folds. The absence of a PVD was statistically associated with the presence of a retinal fold (Fisher's exact test, P < 0.0001). Interestingly, the presence of a PVD was also significantly correlated with retinal fold height (Mann-Whitney U test, P < 0.0001). Therefore, we hypothesized that retinal folds result from postmortem vitreoretinal traction caused by eyeball flaccidity. We also believe that the loss of retinochoroidal hydrostatic pressure plays a role. It is important that forensic pathologists not confuse a postmortem retinal fold with traumatic retinal detachment or perimacular retinal folds caused by child abuse. When child abuse is suspected, forensic pathologists should perform enucleation and a subsequent histological examination for confirmation.

Three cases of suprachoroidal hemorrhage associated with chest compression or asphyxiation and detected using postmortem computed tomography.

We report 3 cases of suprachoroidal hemorrhage (SCH) found to be triggered by increased intrathoracic pressure and detected using postmortem computed tomography (PMCT). Case 1 was a man aged in his 50s who was found dead at a landslide site. The autopsy showed clogging of the upper respiratory tract with soil debris from the landslide. The cause of death was determined to be asphyxia. PMCT showed SCH in both eyes, which was believed to be caused by chest compression or choking on the soil debris from the landslide. Case 2 was a woman aged in her 60s who was found dead in the sea. The autopsy revealed injuries primarily to her chest. We concluded that the cause of death was drowning. PMCT showed SCH in her right eye that was believed to be caused by chest compression. Case 3 was a woman aged in her 80s who was buried in a snowdrift and potentially died from hypothermia. PMCT showed SCH in both eyes, which was considered to be from an increase in intrathoracic pressure that might have been caused by the burial in the snow. Histological findings showed serous retinal detachment associated with retinal pigment epithelium damage due to SCH, which indicated that she was alive for several hours after the onset of SCH. The increase in intrathoracic pressure caused by dyspnea or chest compression was considered responsible for the onset of SCH in all of the present cases. PMCT might assist with the differential diagnosis of traumatic asphyxiation by SCH.

Four cases of orbital hyperdensity identified by postmortem computed tomography.

Postmortem computed tomography (PMCT) has become a common examination method in the field of forensic medicine. Head computed tomography provides information of the orbit and eyes, and forensic pathologists may come across abnormal intraocular findings of cadavers upon PMCT. Here, we present four cases in which we identified orbital hyperdensity by PMCT. The first case showed calcified senile scleral plaques (CSSP), whereas the second case showed foreign bodies in the palpebral fissure, which resembled CSSP upon PMCT. The third case showed signs of silicone oil injection in the eye, while the fourth case showed bilateral phthisis bulbi. In the first case, the presence of CSSP was found to be helpful for age estimation, whereas the findings of cases 3 and 4 aided in the personal identification of the subjects. As demonstrated by these cases, intraocular PMCT findings may provide highly useful information, and correct interpretation of the intraocular PMCT findings by forensic pathologists is hence crucial.