Development of prevention strategies against bath-related deaths based on epidemiological surveys of inquest records in Kagoshima Prefecture.

Sudden death in the bathroom (bath-related death) occurs more frequently in Japan than in other countries. To clarify the epidemiological characteristics of bath-related deaths, we reviewed inquest records of deaths in Kagoshima Prefecture from 2006 to 2019. We identified 2689 cases of bath-related death. Of these cases, 90% were among people aged ≥ 65 years. The majority occurred in a home bathtub between 16:00 and 20:00. Most deaths (52.0%) occurred in winter (December-February), and there were extremely strong negative correlations with the environmental temperatures (maximum, minimum, and mean) on the day of death. We identified the environmental temperature during cold winter months that bath-related deaths are likely to occur in Kagoshima, although further investigation concerning the effects of other confounding factors is required. Forensic autopsies have only been performed in 29 cases and the cause of death was not diagnosed correctly in the majority of cases. Although autopsies are essential to elucidate the pathogenesis of the deaths, it is difficult to increase the rate of autopsies under the current Japanese death investigation system. Therefore, we suggest that the best way to prevent bath-related death is establishing an "Alert system" based on our results, and to have people refrain from bathing on dangerous days.

Epidemiological analysis of intramuscular hemorrhage of respiratory and accessory respiratory muscles in fatal drowning cases.

The postmortem diagnosis of drowning death and understanding the mechanisms leading to drowning require a comprehensive judgment based on numerous morphological findings in order to determine the pathogenesis and epidemiological characteristics of the findings. Effortful breathing during the drowning process can result in intramuscular hemorrhage in respiratory and accessory respiratory muscles. However, the characteristics of this phenomenon have not been investigated. We analyzed the epidemiological characteristics of 145 cases diagnosed as drowning, in which hemorrhage, not due to trauma, was found in the respiratory muscles and accessory respiratory muscles. Hemorrhage was observed in 31.7% of these cases, and the incidence did not differ by gender or drowning location. The frequency of hemorrhage was significantly higher in months with a mean temperature below 20°C than in months above 20°C, suggesting a relationship between the occurrence of hemorrhage and low environmental temperature. Moreover, the frequency of hemorrhage was significantly higher in the elderly (aged ≥65 years) compared to those <65 years old. In the elderly, the weakening of muscles due to aging may contribute to the susceptibility for intramuscular hemorrhage. Moreover, these intramuscular hemorrhages do not need to be considered in cases of a potential bleeding tendency due to disease such as cirrhosis or medication such as anticoagulants. Our results indicate that intramuscular hemorrhage in respiratory and accessory respiratory muscles can serve as an additional criterion to differentiate between fatal drowning and other causes of death, as long as no cutaneous or subcutaneous hematomas above the muscles with hemorrhages are observed. In addition, the epidemiological features that such intramuscular hemorrhage is more common in cold environments and in the elderly may provide useful information for the differentiation.

Association of Daily Home-Based Hot Water Bathing and Glycemic Control in Ambulatory Japanese Patients with Type 2 Diabetes Mellitus During the COVID-19 Pandemic: A Multicenter Cross-Sectional Study.

PURPOSE: To clarify the relationship between daily hot water bathing (HWB) at home and glycemic control in middle-aged and elderly ambulatory patients with type 2 diabetes mellitus (T2DM). METHODS: We defined hemoglobin A1c (HbA1c) as the main outcome. We set 7.0% based on the mean value of the dependent variable as the cut-off point for analysis. Frequency of HWB was an explanatory variable. A two-sample t-test was used to compare between groups with continuous variables. Multiple logistic regression analysis was performed for frequency, adjusted age, sex, BMI, T2DM duration (Model 1), and other confounding factors (Model 2). Odds ratio (OR) and 95% confidence interval (95% CI) were calculated. RESULTS: Among 838 patients, there was a significant difference (p<0.001) in age between males (n=528, 62.8±8.7 years) and females (n=310, 65.0±8.1 years). In Model 1, compared with participants who used HWB more than seven times a week, those with poorly controlled HbA1c were significantly associated with low frequency of HWB: four to six times a week (OR 1.32, 95% CI 0.87-1.99) and less than three times a week (OR 1.43, 95% CI 0.98-2.10); p-value for overall trend was 0.041. In Model 2, p-value for overall trend was 0.138. CONCLUSION: A higher frequency of HWB was moderately associated with a decreased risk of poor glycemic control in middle-aged and elderly ambulatory patients with T2DM.

Primed neutrophil infiltrations into multiple organs in child physical abuse cases: A preliminary study.

Physical abuse of the elderly induces a massive primed neutrophil infiltration into the lung and liver through chemotaxis by interleukin (IL)-8, similar to cases of traumatic or hemorrhagic shock. Here, we used immunohistochemical analyses to investigate this infiltration in cases of physically abused children. In addition, we examined the expression of neutrophil elastase (NE) as the inflammatory mediator and α1-antitrypsin (AAT) as the elastase inhibitor. The number of neutrophils in the abuse cases was increased significantly in the heart, lung, liver, and kidney, compared with that of control cases. IL-8-positive cells and NE-positive cells in all organs of abuse cases were significantly greater than those in control cases. Large quantities of oxidized AAT, which fails to inactivate NE and results in tissue damage, was detected in the liver of abuse cases. Neutrophil infiltration showed positive correlation with the degree of systemic accumulation of non-fatal injuries caused by repetitive abusive behavior. Although further investigation using more autopsy samples is necessary, results of our preliminary study indicate that massive neutrophil infiltration induced by IL-8 in multiple organs is a new complementary diagnostic indicator of physical abuse in children. Moreover, the demonstration of NE-positive cells and oxidized AAT provides firm evidence of tissue damage.

Interleukin (IL)-8 immunoreactivity of injured axons and surrounding oligodendrocytes in traumatic head injury.

Interleukin (IL)-8 has been suggested to be a positive regulator of myelination in the central nervous system, in addition to its principal role as a chemokine for neutrophils. Immunostaining for beta-amyloid precursor protein (AßPP) is an effective tool for detecting traumatic axonal injury, although AßPP immunoreactivity can also indicate axonal injury due to hypoxic causes. In this study, we examined IL-8 and AßPP immunoreactivity in sections of corpus callosum obtained from deceased patients with blunt head injury and from equivalent control tissue. AßPP immunoreactivity was detected in injured axons, such as axonal bulbs and varicose axons, in 24 of 44 head injury cases. These AßPP immunoreactive cases had survived for more than 3h. The AßPP immunostaining pattern can be classified into two types: traumatic (Pattern 1) and non-traumatic (Pattern 2) axonal injuries, which we described previously [Hayashi et al. Int. J. Legal Med. 129 (2015) 1085-1090]. Three of 44 control cases also showed AßPP immunoreactive injured axons as Pattern 2. In contrast, IL-8 immunoreactivity was detected in 7 AßPP immunoreactive and in 2 non-AßPP immunoreactive head injury cases, but was not detected in any of the 44 control cases, including the 3 AßPP immunoreactive control cases. The IL-8 immunoreactive cases had survived from 3 to 24 days, whereas those cases who survived less than 3 days (n=29) and who survived 90 days (n=1) were not IL-8 immunoreactive. Moreover, IL-8 was detected as Pattern 1 axons only. In addition, double immunofluorescence analysis showed that IL-8 is expressed by oligodendrocytes surrounding injured axons. In conclusion, our results suggest that immunohistochemical detection of IL-8 may be useful as a complementary diagnostic marker of traumatic axonal injury.

Two different immunostaining patterns of beta-amyloid precursor protein (APP) may distinguish traumatic from nontraumatic axonal injury.

Immunostaining for beta-amyloid precursor protein (APP) is recognized as an effective tool for detecting traumatic axonal injury, but it also detects axonal injury due to ischemic or other metabolic causes. Previously, we reported two different patterns of APP staining: labeled axons oriented along with white matter bundles (pattern 1) and labeled axons scattered irregularly (pattern 2) (Hayashi et al. (Leg Med (Tokyo) 11:S171-173, 2009). In this study, we investigated whether these two patterns are consistent with patterns of trauma and hypoxic brain damage, respectively. Sections of the corpus callosum from 44 cases of blunt head injury and equivalent control tissue were immunostained for APP. APP was detected in injured axons such as axonal bulbs and varicose axons in 24 of the 44 cases of head injuries that also survived for three or more hours after injury. In 21 of the 24 APP-positive cases, pattern 1 alone was observed in 14 cases, pattern 2 alone was not observed in any cases, and both patterns 1 and 2 were detected in 7 cases. APP-labeled injured axons were detected in 3 of the 44 control cases, all of which were pattern 2. These results suggest that pattern 1 indicates traumatic axonal injury, while pattern 2 results from hypoxic insult. These patterns may be useful to differentiate between traumatic and nontraumatic axonal injuries.

Temporal changes of the adrenal endocrine system in a restraint stressed mouse and possibility of postmortem indicators of prolonged psychological stress.

We investigated temporal changes of adrenal endocrine systems through the hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenomedullary (SA) axis in restraint stressed mice. Restraint stress for 1 day to 3 weeks caused a significant increase in serum levels of ACTH and glucocorticoids accompanied with an increase in adrenal weights, indicating activation of the HPA axis. Reflecting the overproduction of glucocorticoids, adrenal cholesterol content decreased. Moreover, adrenal gene expression involved in cholesterol supply, including scavenger receptor-class B type I, HMG-CoA reductase, and hormone-sensitive lipase, was increased over the same period. After 4 weeks stress, all of these changes returned to control levels. In contrast, adrenal gene expression of chromogranin A, which is cosecreted with catecholamine via the SA axis, was increased with 1 day to 2 weeks of stress, and decreased with 3-4 weeks of stress. Our results suggest that analyses of adrenal endocrine systems based on the combination of several markers examined here would be useful for not only proving prolonged psychological stress experience but also determining its duration.

Forensic diagnosis of ante- and postmortem burn based on aquaporin-3 gene expression in the skin.

In order to diagnose death associated with fire, it is essential to show that the person was exposed to heat while still alive. We investigated both AQP1 and AQP3 expression in the skin of an experimental burn model, as well as in forensic autopsy cases, and discuss its role in the differential diagnosis of ante- and postmortem burns. In animal experiments, there was no difference in AQP1 gene expression among four groups (n=4): antemortem burn, postmortem burn, mechanical wound, and control. However, AQP3 expression in the antemortem burn was increased significantly compared with that of the other groups even at 5min after burn. Water content of the skin was decreased significantly by the burn procedure. Consistent with animal experiments, AQP3 gene expression in the skin of antemortem burn cases was increased significantly compared with postmortem burns, mechanical wounds, and controls (n=12 in each group). These observations suggest that dermal AQP3 gene expression was increased to maintain water homeostasis in response to dehydration from burn. Finally, our results suggest that AQP3 gene expression may be useful for forensic molecular diagnosis of antemortem burn.

Temporal expression of wound healing-related genes in skin burn injury.

Determination of the age of burns, as well as of wounds induced mechanically, is essential in forensic practice, particularly in cases of suspected child abuse. Here, we investigated temporal changes in the expression of 13 genes during wound healing after a burn. The expression of cytokines (IL-1ß, IL-6, IL-10, TNF-α, and IFN-γ), chemokines (KC, MCP-1), proliferative factors (TGF-ß, VEGF), proteases (MMP-2, 9, 13) and type I collagen in murine skin was examined by real-time PCR at 3, 6, 9, and 12 h and 1, 2, 3, 5, 7, and 14 days after a burn. Based on macroscopic and histological appearance, the healing process of a burn consists of 3 phases: inflammatory (from 3 h to 1 day after the burn), proliferative (from 1 to 7 days), and maturation (from 7 to 14 days). Expression of IL-1ß, IL-6, TNF-α, IFN-γ and KC increased significantly in a biphasic pattern from 3 or 6 h to 12 h or 1 day and from 3 or 5 days to 7 days. Expression of MCP-1 increased significantly from 6 h to 5 days. Expression of both IL-10 and TGF-ß increased significantly from 12 h to 7 days. Expression of VEGF, MMP-2, MMP-13 and type I collagen increased significantly from 3 days to 7 or 14 days. Expression of MMP-9 increased significantly from 6 h to 14 days. Our results suggest that evaluating the expression of a combination of these genes would enable the exact estimation of the age of a burn.

Postmortem multislice computed tomography (pmMSCT) imaging of hangman's fracture.

First described in 1965, avulsion of the neural arch from the vertebral body of the axis (C2) as a sequel to violent and rapid hyperextension of the head was termed hangman's fracture because of its similarity to the injury observed after judicial hanging. Since diagnosing such a fracture at autopsy is difficult because of its anatomic position, accurate determination of features of a hangman's fracture in cases of non-judicial hanging has not been systematically elucidated. We performed a prospective autopsy study visualizing hangman's fractures in 32 cases of hanging using postmortem multislice computed tomography (pmMSCT). A hangman's fracture with a fracture of the vertebral arch adjacent to the C2 vertebral body was only detected in one case (3.1 %). In this case a rarely observed longer drop with a lateral knot was used. Although a hangman's fracture was invariably observed bilaterally in previously reported cases, our case revealed a unilateral fracture at the side corresponding to the location of the knot. Out of the three types of hangman's fracture, pmMSCT is especially useful for detecting type 1 (nonangulated, undisplaced C2 with a normal disk at C2/C3). Also, pmMSCT is superior to conventional radiography in diagnosis, especially when the fracture is extending into the transverse foramen. In conclusion, pmMSCT imaging is useful for detecting hangman's fracture in hanging cases. Accumulating more evidence through pmMSCT will allow clarification of the actual incidence and circumstantial findings of hangman's fracture that have been controversially debated for many decades in the forensic community.

Circumstantial and toxicological features of deaths from self-administered intravenous anesthetic/narcotic agents.

For a better understanding of circumstantial and toxicological findings of fatalities resulting from self-administration of intravenous anesthetic/narcotic agents, medico-legal autopsy files of the State Institute of Legal and Social Medicine Berlin from 1998 to 2011 were reviewed retrospectively. Of a total of 15,300 autopsies, 9 cases of such deaths were identified, and all were health care professionals. Medical supplies for injection were found still on, or near, the body at the scene. Anesthetic/narcotic agents detected were classified into 3 categories, and administered solely or in combination. Propofol was the most common agent, being detected in 6 cases. In 2 out of 6 cases, propofol was detected substantially above therapeutic levels and was considered the cause of death. In the remaining 4 cases, propofol levels were within the therapeutic range, but propofol intoxication was considered as lethal due to it being administered by rapid continuous injection. In 5 cases, injection of opioid narcotics was fatal. Alongside the 2 propofol-detected cases, there was one case where a higher-than-therapeutic level of piritramide and a therapeutic level of alfentanil was identified. Despite suspected usage, remifentanil was not detected due to its rapid metabolism by elastases in one case, and sufentanil was undetectable due to putrefaction in another, but death was attributed to their potent respiratory depressant effects without respiratory assistance. Benzodiazepines were detected in 4 cases. All of them were used together with propofol or opioids, and contributed to death by inhibiting respiration. It is essential to consider means of administration as well as additive or synergistic effects of combined agents when interpreting toxicological results in such cases.