Current state of cause of death determinations in Japan and the need to list the precise underlying cause of death.

When death is caused by a disease, the precise cause of the death must be determined to promote health and contribute to prevention efforts. The circumstances of death should also be clarified so that measures can be taken to prevent the recurrence. Statistics regarding the cause of death must be accurate, and such statistics are shaped by the determination of the cause of death. We examined the annual cause of death rankings and the mortality rate in Japan during the 25-year period 1993-2017. We identified improvements that are needed to provide more precision in the cause of death statistics, with a focus on variations in the rankings, and we describe the peculiar and vulnerable aspects of the Vital Statistics system in Japan; for example, at one time the national government advised physicians to not list "heart failure" as the terminal stage of a condition on a death certificate, and the "heart disease" mortality rate thus tended to decline in that period. The ranking of "heart disease" as a cause of death decreased, but its mortality rate subsequently increased again. In addition, the "pneumonia" mortality rate has remained high over the past few years, but it abruptly decreased in 2017, when "aspiration pneumonia" was separated as a cause from other pneumonias. The "senility" mortality rate has increased annually, and it is a leading cause of death. It is important that physicians understand the underlying causes of death and provide that without being influenced by the reporting customs of the times.

Stressors increase leptin receptor-expressing thymic epithelial cells in the infant/child thymus.

The thymus, the organ that is the most sensitive to stress, presents acute involution as a result of exposure to strong stress in childhood. Thymic involution is thus often considered evidence of child abuse/neglect in forensic autopsies. A portion of the thymic epithelial cells express leptin receptor, and leptin showed a thymo-protective function against stress-induced thymic involution in an animal model. Leptin receptor-expressing thymic epithelial cells (LR-TECs) may play a key role in the thymic remodeling provoked by a stressful environment. Here, we sought to clarify the changes of histopathological findings and human LR-TECs in stressful environment. We examined human thymus specimens obtained from 40 forensic autopsy cases (26 male, 14 female; age 21 to 3221 days). We divided the cases into stressor-positive (SP, n = 29) and stressor-negative (SN, n = 11) groups. Cases were classified according to the histological classification of thymic involution and investigated by leptin receptor immunostaining. The results revealed that (1) the SP group showed obvious histological thymic involution (p < 0.01) and (2) the LR-TECs/TECs ratio in the cortex was markedly and significantly increased in the SP group compared to the SN group (p < 0.01). The increase in the cortical LR-TECs/TECs ratio in the SP group may be part of the stress response mechanism in the human thymus. We thus speculate that the quantification of LR-TECs in the thymic cortex is a valuable stress marker for forensic autopsy cases.

Detection of butane gas inhalation at 16days after hypoxic encephalopathy: A case report.

In Japan, there are increasing reports of death by poisoning following butane abuse. To determine the specific cause of death in such cases, it is important to confirm the presence of fuel gas components in the body, although careful analysis is required because of their volatile properties. In most reported cases, the subject died suddenly during or immediately after butane aspiration. Thus, the butane concentration in the samples from the deceased should be relatively high. Herein, we present a case of an 18-year-old man found with cardiopulmonary arrest, who then exhibited hypoxic encephalopathy for 16days in a hospital. At autopsy, we detected hypoxic encephalopathy, pneumonia, and ischemia-reperfusion injury of the myocardium, while the cause of cardiac arrest remained unclear. Toxicological analysis was then performed for fuel gas components in several specimens collected at autopsy. Results showed that n-butane and isobutane were detected in the adipose tissue at 16days after inhalation, indicating a role of butane gas inhalation as the cause of death. These data suggest that adipose tissue may be the most appropriate analysis sample to be collected at postmortem in cases where involvement of volatile and fat-soluble gas inhalation is suspected.

A rare case of steering wheel injury causing coronal-plane pancreatic lacerations.

The incidence of pancreatic injury after blunt abdominal trauma is extremely low. A timely and accurate diagnosis is important, as a delay could be life-threatening. In this case, a 70-year-old driver crashed a car into a concrete wall at low speed. He was transported to the emergency hospital but died about 9.5h later with the cause of death unknown. An autopsy revealed that his pancreas was lacerated in the coronal plane and there was mesenteric contusion. Cause of death was determined to be blood loss resulting from pancreatic and mesenteric contusion. The mechanism of the injury was considered to be a very rare "degloving," caused by the impact from the steering wheel. It is therefore important to keep in mind possible pancreatic damage when examining blunt trauma to the abdomen, especially in traffic accident cases.

A Long-term Study of the Association between the Relative Poverty Rate and Suicide Rate in Japan.

The annual number of suicides in Japan totaled around 23,000 in 1997 and abruptly increased to around 31,000 in 1998. This figure has remained high since then. This abrupt increase in the number of suicides was primarily due to an increase in suicides occasioned by economic concerns. The association between various economic factors and suicide must be studied in detail and over the long term in order to ascertain the association between economic concerns and suicide. This study examined the relative poverty rate and the suicide rate in Japan over 30 years and discussed the association between those two rates. The results suggest that the relative poverty rate may be associated with the suicide rate for both sexes. This association is true for men in particular. The organizations and professionals involved in implementing suicide prevention measures should be cognizant of the current findings and consider formulating additional specific measures.

Multiple infectious pseudoaneurysms: An autopsy case.

A 47-year-old Japanese woman died unexpectedly 11 days after admission due to acute cerebellar infarction. The patient had a history of Sjögren syndrome with long-term steroid therapy, hypertension, thalamic infarction and amphetamine psychosis. Multiple pseudoaneurysms in both the aorta and coronary artery were found at autopsy, and one located in the aortic root had ruptured into the pericardium resulting in sudden unexpected death. The detailed examination suggested that the pseudoaneurysms resulted from microbial infection to the arterial wall via the vasa vasorum. Immunosuppression induced by the long-term steroid therapy and abused drug injection could have influenced the formation of pseudoaneurysms.

A preliminary study on postmortem interval estimation of suffocated rats by GC-MS/MS-based plasma metabolic profiling.

Estimation of postmortem interval (PMI) is an important goal in judicial autopsy. Although many approaches can estimate PMI through physical findings and biochemical tests, accurate PMI calculation by these conventional methods remains difficult because PMI is readily affected by surrounding conditions, such as ambient temperature and humidity. In this study, Sprague-Dawley (SD) rats (10 weeks) were sacrificed by suffocation, and blood was collected by dissection at various time intervals (0, 3, 6, 12, 24, and 48 h; n = 6) after death. A total of 70 endogenous metabolites were detected in plasma by gas chromatography-tandem mass spectrometry (GC-MS/MS). Each time group was separated from each other on the principal component analysis (PCA) score plot, suggesting that the various endogenous metabolites changed with time after death. To prepare a prediction model of a PMI, a partial least squares (or projection to latent structure, PLS) regression model was constructed using the levels of significantly different metabolites determined by variable importance in the projection (VIP) score and the Kruskal-Wallis test (P < 0.05). Because the constructed PLS regression model could successfully predict each PMI, this model was validated with another validation set (n = 3). In conclusion, plasma metabolic profiling demonstrated its ability to successfully estimate PMI under a certain condition. This result can be considered to be the first step for using the metabolomics method in future forensic casework.

Evaluation of thymic volume by postmortem computed tomography.

The thymus is exceedingly sensitive to stress and undergoes abrupt involution as a result of exposure to strong stress in early childhood. Therefore, thymic involution is often utilized to assess the presence of a stressful environment, such as an environment involving child abuse, in forensic medicine. In recent years, computed tomography (CT) has been commonly used in the daily practice of forensic medicine. We have focused on the thymic volume in postmortem CT images to evaluate the presence of a stressful antemortem environment. We calculated the thymus volume from postmortem CT images of children under six years old and demonstrated that the volume showed a positive correlation with the real weight obtained from an autopsy. The evaluation of thymic volume by CT may make it possible for us to identify child maltreatment. The most useful feature of this application of CT is to be able to demonstrate thymic involution less invasively in a surviving victim.

Traumatic basal subarachnoid hemorrhage suspected to have been caused by contrecoup cerebellar contusions: a case report.

Traumatic cerebellar hemorrhagic contusions are infrequent, and the pathogenic mechanism involves a coup injury that is associated with motor vehicle accidents in most cases. Traumatic basal subarachnoid hemorrhage (TBSAH) is commonly reported after blunt trauma to the neck or unrestricted movement of the head, and the source of the hemorrhage is most frequently identified in the vertebrobasilar arteries. A 55-year-old woman who was addicted to alcohol was found dead in her bed. She had a bruise on the left side of her posterior parietal region, and autopsy revealed massive subarachnoid hemorrhage at the base of the brain; the hematoma was strongly attached to the right lower surface of the cerebellar hemisphere. No ruptured cerebral aneurysms, arteriovenous malformations or vertebrobasilar artery leakage were detected. Hemorrhagic cerebellar contusions were regarded as the source of the TBSAH. This is the first report of TBSAH suspected to have been caused by contrecoup cerebellar contusions.

Sudden death of a child because of an intestinal obstruction caused by a large congenital mesenteric defect.

Transmesenteric hernias are internal hernias caused by a congenital defect in the mesentery. They are rare causes of intestinal obstruction, but most commonly affect the small bowel. We report an unexpected death of an infant with a bowel obstruction caused by a congenital mesenteric defect, which was undiagnosed despite visits to three different hospitals. Mesenteric defects are usually 2-3 cm in diameter. At autopsy, we found an oval, 14 × 7 cm congenital defect in the ileal mesentery through which the small bowel had herniated. Diagnosis of such defects remains difficult, even with currently available imaging techniques. Diagnosis is particularly difficult in infants who usually have nonspecific symptoms. Therefore, it is important that sudden unexpected deaths in children undergo full forensic evaluation to establish the precise cause of death. It is also important for forensic physicians to inform clinicians of the risk of such diseases, particularly in emergency situations.

Potential medical adverse events associated with death: a forensic pathology perspective.

OBJECTIVE: To determine the incidence of potential medical adverse events among patients undergoing forensic autopsy, and to present the characteristics of potential medical adverse events. DESIGN: Retrospective review of consecutive autopsy records. SETTING: Department of Forensic Medicine, the Jikei University School of Medicine, Tokyo, Japan. PARTICIPANTS: A total of 3355 forensic autopsy cases between 1983 and 2006. MAIN OUTCOME MEASURES: Incidence of potential medical adverse events identified in decedents undergoing forensic autopsy, classified by actual occurrence as 'confirmed', 'equivocal' and 'negative' cases; proportion of potential diagnostic, performance and system errors among potential medical adverse events. RESULTS: Of 291 autopsies (8.7%) with potential medical adverse events, 66 cases (22.7%) were confirmed, 42 cases (14.4%) were negative and 183 cases (62.9%) were equivocal. Confirmed cases consisted of potential diagnostic errors in 49 cases (74.2%) and performance errors in 17 cases (25.8%). Equivocal cases included 99 cases associated with potential diagnostic errors (54.1%) and 60 cases associated with potential system errors (32.8%). In 38 of the confirmed cases (57.5%), serious exacerbation of patient condition occurred outside the medical facility. CONCLUSIONS: Potential medical adverse events are not uncommon in decedents undergoing forensic autopsy. They are particularly associated with potential diagnostic errors. Forensic autopsy may provide information that could be used to improve care and reduce deaths due to potential medical adverse events.

A novel method for the diagnosis of drowning by detection of Aeromonas sobria with PCR method.

The acid digestion method has been widely used for the diagnosis of death by drowning, but it is not always sensitive. However, there has been no definitive method to replace acid digestion until now. We speculate that bacteria are more useful markers than plankton for the diagnosis of death by drowning. In this study, from the preserved blood samples of 32 freshwater drowning cases, specific DNA fragments of Aeromonas sobria, one of the most common aquatic bacteria, were examined using PCR. The DNA fragments of the bacterium were detected from 27 of 32 cases with first round PCR or nested-PCR. The remaining 5 cases in which bacterial DNA was not detected had longer storage periods for the blood samples and shorter time intervals from drowning to death. These results indicate that the present method can be applied to the diagnosis of death by drowning.

Effects of polymorphisms in untranslated regions of the class I alcohol dehydrogenase (ADH) genes on alcohol metabolism in Japanese subjects and transcriptional activity in HepG2 cells.

Human class I ADH is a dimmer formed by the random association of three types of subunits (alpha, beta and gamma) encoded by ADH1A, ADH1B, and ADH1C, respectively. Different kinetic properties were reported due to polymorphisms of ADH1B Arg47His and ADHIC Ile349Val. Besides these polymorphisms in the coding region, various mutations in the promoter region and 3' untranslated (UTR) region, which possibly affect expression and degradation rate, were recently reported. In this study, to asses the involvement of each genotype in alcohol metabolism in humans, our previously collected data set of blood EtOH and AcH changes were reanalyzed with regard to the ALDH2 Glu487Lys genotype. The effects of genotypes and haplo-types on transcriptional activity were also examined by a luciferase reporter assay by cloning the promoter region and 3' UTR corresponding to each polymorphism and transfecting into HepG2 cells. Among the nine polymorphisms, including ADH1B Arg47His and ADH1C Ile349Val, blood EtOH levels were significantly affected by polymorphisms ADH1B -451G>T, ADH1B +52A>G, ADH1B +531G>A, ADH1B +1176AG>del. and ADH1A -55C>T in ALDH2 Glu/Glu subjects. In the ALDH2 Glu/Lys genotype background, only ADH1C -254G>C and ADH1B His47Arg showed significant effects on blood EtOH. These five loci (and the two loci which had significant effect on blood EtOH in ALDH2 Glu/Glu and Glu/Lys subjects) also showed strong linkage disequilibrium. In comparison to the in vivo study on alcohol metabolism, significantly higher transcriptional activities in ADH1B -451T (rather than C) promoter and ADH1C-254 G (rather than C) promoter were observed in a luciferase assay in HepG2 cells. In conclusion, polymorphisms in the untranslated regions of ADH class I genes were demonstrated to clearly affect individual differences in alcohol metabolism. Especially, ADH1B -451G>T, ADH1C-254G>C polymorphisms were suggested to have functional significance with regard to transcriptional activity to the linkage equilibrium of polymorphisms ADH1B His47Arg and ADH1C Ile349Val.

Polymorphisms in the promoter region of the human class II alcohol dehydrogenase (ADH4) gene affect both transcriptional activity and ethanol metabolism in Japanese subjects.

Class II alcohol dehydrogenase (pi-ADH), encoded by alcohol dehydrogenase (ADH4), is considered to contribute to ethanol (EtOH) oxidation in the liver at high concentration. Four single nucleotide polymorphisms (SNPs) were found in the promoter region of this gene. Analysis of genotype distribution in 102 unrelated Japanese subjects revealed that four loci were in strong linkage disequilibrium and could be classified into three haplotypes. The effects of these polymorphisms on transcriptional activity were investigated in HepG2 cells. Transcriptional activity was significantly higher in cells with the -136A allele than in those with the -136C allele. To investigate whether this difference in transcriptional activity caused a difference in EtOH elimination, previous data on blood EtOH changes after 0.4 g/kg body weight alcohol ingestion were analyzed. When analyzed based on aldehyde dehydrogenase-2 gene (ALDH2) (487)Glu/Lys genotype, the significantly lower level of EtOH at peak in subjects with -136C/A and -136A/A genotype compared with subjects with -136C/C genotype indicated that -136 bp was a suggestive locus for differences in EtOH oxidation. This effect was observed only in subjects with ALDH2 (487)Glu/Glu. These results suggested that the SNP at -136bp in the ADH4 promoter had an effect on transcriptional regulation, and that the higher activity of the -136A allele compared with the -136C allele caused a lower level of blood EtOH after alcohol ingestion; that is, individuals with the -136A allele may consume more EtOH and might have a higher risk for development of alcohol dependence than those without the -136A allele.

A promoter polymorphism in the ALDH2 gene affects its basal and acetaldehyde/ethanol-induced gene expression in human peripheral blood leukocytes and HepG2 cells.

AIMS: To assess the effect of the -360G/A polymorphism in the promoter region of the human aldehyde dehydrogenase-2 (ALDH2) gene on its transcription, basal and acetaldehyde/ethanol-induced gene expression was examined by in vivo and in vitro experiments. METHODS: Human peripheral blood leukocytes were collected before and after alcohol ingestion (0.4 g/kg body weight) in 21 healthy young Japanese volunteers with a deficient phenotype of ALDH2 ((487)Glu/Lys), and the levels of ALDH2 mRNA were quantified by real-time RT-PCR. The transcriptional activity of the ALDH2 promoter was investigated by a reporter assay using HepG2 cells in the presence or absence of acetaldehyde/ethanol. RESULTS: The basal level of ALDH2 mRNA was significantly higher in -360A heterozygous subjects than in -360G homozygous subjects. In all subjects, regardless of the genotype, ALDH2 mRNA increased following ethanol ingestion. The promoter activity of a reporter plasmid for -360G was significantly lower than that of a reporter plasmid for -360A. Exposure to acetaldehyde induced a significant increase in the transcriptional activity of the -360G reporter, but not the -360A reporter. CONCLUSIONS: In vivo and in vitro experiments showed that the -360G allele has lower basal transcriptional activity than the -360A allele, whereas acetaldehyde/ethanol-induced gene expression, in general, seems to be more enhanced in individuals homozygous for the -360G allele than in those with the -360A allele. Thus, the promoter polymorphism may be involved in individual differences in acetaldehyde elimination.

Effects of functional polymorphisms related to catecholaminergic systems on changes in blood catecholamine and cardiovascular measures after alcohol ingestion in the Japanese population.

BACKGROUND: The polymorphism of human aldehyde dehyrogenase-2 (ALDH2) Glu(487)Lys is well known to be a crucial factor underlying the genetic background for alcohol sensitivity in Asian populations. Subjects with the inactive Lys(487) allele show a marked increase in blood acetaldehyde level after alcohol intake, which results in facial flushing and various cardiovascular-related symptoms. However, other polymorphisms related to catecholaminergic systems that tightly regulate the activity of the sympathetic nervous system may also influence the physiological changes after acute alcohol intake. METHODS: We investigated whether, together with the ALDH2 Gly(487)Lys and ADH1B Arg(47)His genotype, putative functionally important polymorphisms, including 9 loci in 7 human genes, were associated with changes in blood catecholamine levels and cardiovascular measures after alcohol ingestion. Forty-nine young Japanese males were subjected to blood catecholamine analysis after alcohol ingestion. Among them, 28 were also subjected to heart rate variability and blood pressure analysis. The contribution of polymorphisms to the alcohol-induced response was analyzed by multiple regression analysis. RESULTS: Among the polymorphisms examined in this study, haplotypes of the phenylethanolamine N-methyltransferase (PNMT) promoter [(-182bpG/A)_(-387bpG/A)] and catechol-O-methyltransferase (COMT) exon 4 [(Ex4 + 119bpC/G)_(Ex4 + 138bpG/A), Leu(136)Leu_Val(158)Met] are suggested to have functionally important effects on alcohol-induced cardiovascular symptoms by affecting blood catecholamine levels. The neuropeptide Y (NPY) promoter C-1450T genotype is also suggested to be involved in the individual differences in regulation of catecholamine secretion. CONCLUSIONS: This study suggested that these common polymorphisms of genes related to catecholaminergic systems, as well as those of the alcohol metabolizing system, are significant for understanding the basis of individual differences in alcohol sensitivity.