Abstract Aim The outbreak of the new Coronavirus Disease 2019 (COVID‐19) has spread and caused a public healthcare crisis. The habit of toothbrushing is the critical and fundamental measure for controlling the oral health. There has been no report on whether tooth brushing habit is associated with a risk of severity of COVID‐19 infection. We examined the association between toothbrushing habits and the severity of COVID‐19 infections. Methods The cross‐sectional data were used from the Japan COVID‐19 and Society Internet Survey (JACSIS), a large‐scale Internet survey conducted in 2022 (n = 32 000). If the severity of COVID‐19 infection worsens, hospital treatment or the respiratory ventilator treatment may be required. We examined whether daily toothbrushing is a factor on the suppression of the exacerbation of COVID‐19 infection. Results From all participants, 4756 people were diagnosed with SARS‐CoV‐2 infection. Multivariable logistic regression analysis showed that toothbrushing habit was a significant factor related to the severity of COVID‐19 infection. Conclusion Daily toothbrushing is a very important factor for preventing the exacerbation of COVID‐19 infection.

BACKGROUND: Most cancers are lifestyle-related and are thus preventable. Lifestyle habits can be improved by individual efforts; for example, because oral health is suggested to play a preventive role in cancer risk, toothbrushing is considered a critical and fundamental measure for controlling oral health. This study aimed to investigate the association between toothbrushing and cancer risk. METHODS: Cross-sectional data from the Japan COVID-19 and Society Internet Survey, a large-scale (n = 32,000) online survey conducted in 2022, were used. From September 12 to October 19, 2022, questionnaires were distributed to candidates selected by simple random sampling from a Japanese Internet research company's panelists to represent the Japanese population. The association between toothbrushing and cancer risk according to cancer prevalence was then analyzed. RESULTS: Among all 32,000 participants, 2,495 (7.8%) who had any cancer previously were analyzed. Multivariable logistic regression analysis revealed a significant association between toothbrushing habit and cancer risk. CONCLUSION: The findings of this study suggest that daily toothbrushing is essential for maintaining oral health and preventing cancer.

PURPOSE: During the Coronavirus Disease 2019 (COVID-19) pandemic, there has been concern about nosocomial infections acquired through dental practice, where machines - such as air turbines - that generate aerosols are used, and where there are many opportunities to come into contact with saliva and blood. Because there is no report to date on whether dental treatment is associated with a risk of SARS-CoV-2 infection in Japan, the aim of the present cross-sectional study was to examine the risk of SARS-CoV-2 infection associated with dental treatment. MATERIALS AND METHODS: Cross-sectional data were gathered from the Japan COVID-19 and Society Internet Survey (JACSIS), a large-scale internet survey conducted in 2021 (n=28,175). From September 27, 2021, to October 30, 2021, the questionnaires were distributed to candidates selected from the panelists of a Japanese Internet research company to represent the Japanese population regarding age, sex, and residential prefecture using a simple random sampling procedure. The risk of SARS-CoV-2 infection related to dental treatment was examined and analysed. RESULTS: Multivariable logistic regression analysis showed that younger age, male sex and living alone were statistically significant factors positively associated with SARS-CoV-2 infection, whereas the presence or absence of dental treatment was not statistically significantly correlated with SARS-CoV-2 infection. CONCLUSION: The present epidemiological study showed that dental treatment is not a positive risk factor for SARS-CoV-2 infection in Japan.

Aims Since it is known that oral problems affect various medical diseases, the effects of restrictions on visits for dental treatment on exacerbations of various systemic medical diseases were examined.Method and materials The data were used from the Japan COVID-19 and Society Internet Survey, a large-scale internet survey conducted in 2021 (n = 28,175). The questionnaires were distributed to 33,081 candidates who were selected to represent the Japanese population regarding age, sex and residential prefecture using a simple random sampling procedure. Patients currently undergoing treatment for diabetes mellitus, hypertension, asthma, cardiocerebrovascular disease, hyperlipidemia, atopic dermatitis, and mental illness, such as depression, were extracted from the total participants. Then, whether discontinuation of dental treatment affected the exacerbation of their systemic disease was examined.Results Overall, 50-60% of patients with each systemic disease had continued to receive dental treatment, and 4-8% of them had discontinued dental treatment. On univariate and multivariate analyses, discontinuation of dental treatment is a risk factor in the exacerbation of diabetes mellitus, hypertensive conditions, asthma, cardiocerebrovascular disease and hyperlipidemia.Conclusion The present epidemiological study showed the relationship between oral health and systemic health, which can provide meaningful insights regarding future medical-dental collaboration in Japan.

BACKGROUND: There is no global consensus on whether pandemic-related factors are related to child abuse. How the pandemic reinforces the risk factors of child abuse might depend largely on individuals' current and past lifestyles in each country. Some changes of lifestyles continue after the pandemic, and it is important to understand which factors are strongly associated with child abuse. We analyzed the pandemic-related characteristics of offenders and non-offenders of self-reported child physical abuse from Internet survey data in Japan and discussed how the pandemic affected physical child abuse and what caused the difference by gender. METHODS: We conducted a cross-sectional study on physical child abuse by caregivers based on the Internet survey conducted from September to October 2021. We divided the participants who were living with their child aged less than 14 years into offenders and non-offenders based on the answer to the question about physical child abuse. The population distribution of the sample was compared to that of caregivers under the same conditions in a large Japanese dataset. The association between their characteristics and physical child abuse was analyzed by univariable and multivariable analysis. RESULTS: The caregivers analyzed in the cohort had similar population distributions to those in the large Japanese dataset. As risk factors of male offenders, "work from home 4-7 days/week," "decreased work," "normal relationships with household members (compared to good relationships)," "COVID-19 infected, both themselves and household members, within a year," "unwillingness to receive COVID-19 vaccination because the license process of the vaccine is doubtful," "high levels of benevolent sexism," and "history of child abuse" were observed. As risk factors of female offenders, "bad relationships with household members (compared to good relationships)," "fear of COVID-19," "COVID-19 infected, both themselves and household members, within a year," "feelings of discrimination related to COVID-19 in the past two months," and "history of child verbal abuse" were observed. CONCLUSIONS: Among male offenders, a significant relationship was observed regarding work-related changes, which may have been reinforced by the pandemic. Furthermore, the extent of the influence and fear of losing jobs caused by these changes may have varied according to the strength of gender roles and financial support in each country. Among female offenders, a significant relationship was observed regarding fear of infection itself, which is consistent with the findings of other studies. In terms of factors related to dissatisfaction with families, in some countries with prominent stereotyped gender roles, men are thought to experience difficulties adapting to work-related changes induced by crises, while women are thought to experience intense fear of the infection itself.

BACKGROUND: The existence of social withdrawal (Hikikomori), which meets the conditions "not attending school", "not working", and "isolated at home for more than 6 months", is gradually being discovered by the world, and their mental health and healing is being highlighted. However, there are very few Hikikomori-related surveys searching their physical health, as it is generally believed that most Hikikomori are adolescents. Middle-aged Hikikomori are also found outside Japan, and their physical health is more important, because Hikikomori have difficulty managing their health due to the socially isolated circumstances and lack of sociability. Although "isolated at home for more than 6 months" could not be used, we extracted a group with low social independence with reference to Hikikomori-related surveys. We estimate that people with low social independence have similar characteristics and problems to Hikikomori, because they share many causes for the problem of difficulty in managing their own health. People with low social independence were identified, and their physical health, such as smoking and drinking status, consultation rates of various diseases, and how often they attend cancer screenings, was analyzed. METHODS: We extracted middle-aged people with low social independence and a control group from the national survey in Japan and stratified them by sex and age. Their health risks were assessed by univariate analysis. Criteria for the experimental group were set with reference to Hikikomori-related surveys. Criteria for the control group included "aged 40-69", "living with parents", "not receiving care for disabilities", and "working". RESULTS: Low-social-independent men had higher consultation rates for diabetes, stroke or cerebral hemorrhage, myocardial infarction or angina, gastric and duodenum diseases, kidney disease, anemia, and depression, while lower consultation rates for dyslipidemia and hypertension. The tendency of non-smoking and non-drinking was found among them. They seldom attended cancer screenings. Low-social-independent women had higher consultation rates for liver and gallbladder diseases, other digestive diseases, kidney diseases, anemia, osteoporosis, and depression. The tendency of non-drinking was the same as men. More heavy smokers were found among those aged 40-49 years, with no significant differences in other age groups. They seldom attended cancer screenings, as well as men. CONCLUSIONS: In terms of current physical health, low-social-independent men have more fatal diseases. Both sexes with low social independence seldom attend cancer screenings and have an increased risk of developing progressive cancer in the future. At least in terms of non-smoking and non-drinking, they live healthier lives than the control group, and what makes low-social-independent men have various fatal diseases is still unclear.

AIM: Psychological distress is associated with poor prognosis in patients with cardiovascular disease (CVD). However, factors related to psychological distress in elderly patients with CVD is less understood. We aimed to investigate the rate of psychological distress in elderly patients with CVD in comparison with that of patients without CVD and to examine the clinical, socioeconomic, and lifestyle factors associated with this condition. METHODS AND RESULTS: Data from a nationwide population-based study in Japan of patients aged ≥ 60 years were extracted, and 1:1 propensity score matching was conducted of patients with and without CVD. Psychological distress was assessed using the K6 scale, on which a score ≥ 6 was defined as psychological distress. Of the 24,388 matched patients, the rate of psychological distress was significantly higher among patients with CVD compared to those without CVD (29.8% vs. 20.5%, p < 0.0001). The multivariate analysis revealed that female sex, comorbidities except hypertension, current smoking, daily sleep duration of < 6  h versus ≥ 8  h, home renter versus owner, retired status, having a walking disability, and lower monthly household expenditure were independently associated with psychological distress. Walking disability was observed in greatest association with psychological distress (odds ratio 2.69, 95% confidence interval 2.46-2.93). CONCLUSION: Elderly patients with CVD were more likely to have psychological distress compared to those without CVD. Multiple factors, including clinical, socioeconomic, and lifestyle variables, were associated with psychological distress. These analyses may help health care providers to identify high risk patients with psychological distress in a population of older adults with CVD.

BACKGROUND: Cardiovascular disease and cancer share a number of risk factors and pathophysiologic mechanisms. Although risk management and early detection of cancer in patients with cardiovascular disease are important, preventive efforts in cardiology and oncology have been relatively disconnected. This study aimed to investigate the rate of cancer screening in a population of older adults with cardiovascular disease. METHODS: This study used data from the 2019 Comprehensive Survey of Living Conditions. Data on participants aged 60 years or older were extracted. The rate of cancer screening and cancer type were investigated between participants with and without cardiovascular disease. RESULTS: Of the 132,442 individuals, participants with cardiovascular disease had a significantly lower rate of cancer screening than those without cardiovascular disease [male: 4401 of 7972 participants (55.2%) vs. 33,744 of 52,106 participants (64.8%), p < 0.001; female: 2500 of 4984 participants (50.2%) vs. 41,319 of 67,380 participants (61.3%), p < 0.001]. The rate of cancer screening was significantly lower in participants with cardiovascular disease than in those without cardiovascular disease, regardless of cancer type, including gastric, colorectal, lung, breast, and gynecologic cancer screening. A history of cardiovascular disease was a negative factor for cancer screening (odds ratio 0.71, 95% confidence interval 0.67-0.74 in male participants; odds ratio 0.80, 95% confidence interval, 0.75-0.85 in female participants). CONCLUSIONS: The rate of cancer screening in elderly participants with cardiovascular disease was lower than that in participants without cardiovascular disease. Physicians should raise awareness regarding early cancer detection in patients with cardiovascular disease.

背景:自宅死割合の,在宅医療普及度の評価指標としての妥当性を検証するとともに,在宅医療に関する主な指標との関連を検討する.方法:神奈川県の人口動態統計及び死体検案数に基づき,検案死と看取り死の実数を死亡の場所別に算出した.また,自宅看取り死割合と在宅医療に関する主な指標との関連を分析した.結果:県全体の自宅死割合は15.7%,看取り死割合は6.9%であった.また,単変量解析の結果,看取り死割合と在宅療養支援診療所以外で訪問診療を実施する一般診療所数の間に,非常に強い正の相関がみられた.結論:在宅医療に特化してない一般診療所が,地域の在宅医療推進について大きな役割を果たしている可能性がある.(著者抄録)

The incidence of death by drowning greatly varies among different prefectures in Japan, mainly due to climate difference. However, there could be other factors affecting the incidence of deaths besides climate, for example, differences in regional death investigation systems. Here, we aimed to elucidate other such factors affecting the mortality data of drowning in the bathtub, especially the effects of discontinuing the medical examiner system. Police data in Kyoto and ambulatory care information in Yokohama were used. Data on cases of elderly individuals found dying or dead in the bathtub at home in winter 2014-2015 were obtained. The following data were collected for each case: age, gender, presence/absence of ambulatory transport, performance of autopsy, and cause of death. The autopsy and drowning rates in Kyoto were 0%, whereas both values in Yokohama were significantly higher at 93.1% and 89.4%, respectively (the denominator of each of the rates is the total number of elderly (aged 65 or over) individuals found dying or dead in the bathtub at home in each city during each winter). Despite no significant difference of incidence of total bath-related death, the proportion of drowning-related deaths was overwhelmingly higher in Yokohama than in Kyoto. The difference can be attributed to the difference in autopsy rates between the two cities, mainly caused by the presence/absence of a medical examiner system. Therefore, we should pay careful attention to future changes in autopsy/drowning rates in Yokohama, and ascertain whether the change might be continuously influenced by the abolishment of this system.

BACKGROUND: No study has yet been performed on the importance of the rate of pure "attended deaths at home," excluding examined deaths subjected to a postmortem examination. Therefore, in the present study, we investigated actual state of pure "attended deaths at home," in order to provide reference data for the future development of end-of-life care at home. METHODS: We performed a detailed survey in Yokohama City according to the type of death, age, and underlying cause of death in cases of home deaths, based on the detailed version of the Vital Statistics Survey Death Forms. Then, we divided deaths occurring in each municipality in Kanagawa Prefecture into two categories: "examined deaths" or "attended deaths," which were also stratified by the place of death, based on the Vital Statistics, and data on number of death cases subjected to postmortem examination from the Kanagawa Prefectural Police Headquarters. RESULTS: In 2013, the survey in Yokohama City showed large differences in age distribution and cause of death between examined and attended deaths. In 2014, home deaths accounted for 15.7% of all deaths in the prefecture, whereas the overall proportion of attended deaths at home was 6.9%. CONCLUSIONS: We should utilize the rate of pure "attended deaths at home" for objective outcome indicator.

Sudden infant deaths might be attributable to adverse reaction to vaccination, but separating them from coincidental occurrences is difficult. This study retrospectively investigated vaccination-related details and postmortem findings for 57 cases of sudden death in children 2 years or younger. Data were extracted from autopsy files at the Department of Forensic Medicine, Tokai University School of Medicine. Vaccination histories were available in 50 cases based on the maternity passbook. Of the 32 cases in which any vaccines were administered, 7 infants (21.9%) had received immunization within 7 days of death. The most frequent vaccine cited as the last immunization before death was Haemophilus influenzae B. Although a temporal association of vaccines with sudden death was present for two 3-month-old and one 14-month-old infants in whom death occurred within 3 days of receiving the H. influenzae type b and other vaccinations, a definitive relationship between the vaccine and death could not be identified. Histopathological examinations revealed pneumonia and upper respiratory infection as contributing to death in their cases. Moreover, all 3 cases showed hemophagocytosis in the spleen and lymph nodes, which are similar features to hemophagocytic lymphohistiocytosis. Judgment of the disorders as truly related to vaccination is difficult, but suspicious cases do exist. Forensic pathologists must devote more attention to vaccination in sudden infant death cases.

BACKGROUND: The solitary death rate in Japan is expected to continue increasing because of its growing super-aged society and the rapid growth of home care in the country. To accurately determine the actual status of solitary deaths, we used a novel analysis method of combining vital statistics and ambulatory care information in Yokohama City. METHODS: Data of persons who died at home in 2013 were obtained from death certificate notifications. We also obtained the emergency transportation records that matched the cases of these death certificate notifications. Then, we gathered information regarding age, gender, marital status, and cause of death for the matched cases. RESULTS: There were 1890 "suspected unnatural deaths," in which most solitary deaths could be included, among all citizens who died at home (n = 4847). We were able to match 1503 of these cases with emergency transportation records. These 1503 cases were divided into two groups, "solitary death" (n = 349) and "un-solitary death" (n = 1154) according to the postmortem interval until finding (PMI-f). Pearson's χ2 tests conducted for the two groups revealed that there were significant differences regarding the proportion of persons who were elderly, unmarried, male, and had a hepatic disease and senility. A logistic regression analysis also showed that an increased likelihood of a prolonged PMI-f was associated with males and an unmarried status with hepatic diseases. CONCLUSIONS: Unmarried, male sex, and liver diseases are independent risks for solitary death in Yokohama City.

We report here lessons learned from an autopsy case involving radioactive materials. We performed an autopsy of an unidentified mummified man with no available medical history whom from imaging findings we suspected had received radioactive seed implants for prostate brachytherapy. We returned the excised prostate and seeds to the body. A few days later, the body was identified by DNA matching and cremated. According to the man's medical record, he had undergone iodine-125 seeds implantation for prostate cancer 11 months earlier. We should have removed the radioactive seeds from the body to prevent radiation exposure to the bereaved family and/or environmental pollution due to cremation. Surprisingly, one seed was found in the stored prostate specimen. Forensic experts should be cognizant of the risk of both radiation exposure in the autopsy room and environmental pollution. We must remain abreast of the latest advances in medicine.

The toxicological detection of the new synthetic cathinone 4′-methyl-α-pyrrolidinohexanophenone (MPHP) in urine samples has been impossible, because much of MPHP is metabolized before its excretion into urine. In this study, we successfully quantified unmetabolized MPHP in urine of an autopsy case using a sensitive method by liquid chromatography–time-of-flight-mass spectrometry. The quantification method showed good linearity in the range of 1.00–100 ng/mL, and the limit of detection was 0.5 ng/mL in human urine. In the autopsy case, the concentrations of MPHP in urine, plasma, and liver tissue samples were determined to be 60.1, 32.9 ng/mL, and 63.1 ng/g, respectively.

Caffeine-containing drinks are popular daily beverages worldwide and highly concentrated caffeine in the form of tablets is easily obtainable in local chemists. It is common to detect caffeine in toxicological screens in autopsy cases, but we always have to take in account that caffeine itself possesses toxicity which may sometimes lead to death The case was a 44-year-old woman who was found dead in her room one day in June. Empty packages of 'Estaron Mocha 12®, accounting for 14 tablets, were found at the scene. The autopsy showed nothing remarkable suggesting external forces, apart from white granules in her stomach. Toxicological analysis revealed 127 mg/L of caffeine concentration in the deceased's blood, which was considered to be fatal. Caffeine intoxication cases have been reported from many countries. Some are caused by accidental overtake of energy drinks, and many others are caused by intentional intake of caffeine tablets. We think that some restrictions will be effective to prevent this kind of death.

PURPOSE: Japanese society has reached an unprecedented level of aging, with elderly people accounting for 25.1% of the population in October 2013. These changes have created concerns regarding deaths among the elderly. In this study, we compared recent forensic autopsy cases with cases from about 20 years ago, with the goal of understanding the context of death among the elderly within Japanese society today. METHODS: We investigated the forensic autopsy records of 297 people aged 65 years or above. In order to examine the effect of residential circumstances, we classified these cases into two groups: people who lived alone (group A) and those who lived with their family (group B). Forty-five of these autopsy cases were conducted about 20 years ago (1989 to 1993) and 252 cases were recent (2009 to 2013). The cases were limited to people who had been found dead or in a critical situation at home. We investigated the first finder, the period of time elapsed between death and discovery, and the cause of death. RESULTS: The incidence of the first finder being a family member was more than 20% greater in group B compared with group A. The proportions of cases for which it took more than three days for someone to find the body or an abnormal situation were about 14% and 7% in groups A and B, respectively, 20 years ago, and about 48% and 19% among the recent cases. These proportions were significantly higher among the recent cases. Among recent cases, a post-mortem elapsed time of more than 3 days occurred more often in group A than group B (p=0.0002). None of the older cases had an unknown cause of death in either group. However, among the recent cases from both groups, 20-30% of cases resulted in unknown causes of death. The incidences of unknown causes of death were significantly higher among the recent cases in both groups (p=0.015) and in group B alone (p=0.037). The incidences of murder cases were significantly lower in group B among the recent cases (p=0.0022). DISCUSSION: Elderly people who live alone are not easily found or aided when in critical situations, and they may only be discovered after death. Prolongation of the postmortem interval (PMI) results in the deterioration of the corpse making determination of cause of death problematic. The results of this study suggest that there are three factors that isolate elderly people and increase the difficulty in determining their cause of death: reduced communication with family members, reduced communication with neighbors or the community, and the increasing prevalence of the nuclear family. In group B, the prolonged discovery time and the increased incidence of unknown causes of death suggest reduced communication with family members, even though the incidence of being found by a family member was higher than in group A. The murder rate was significantly lower in group B, which may suggest that cases of domestic murder were overlooked. Support for a safe life and peaceful ending for the elderly requires a system based on three factors: remote monitoring to ensure safety, the establishment of elderly groups providing mutual support, and increased visits from welfare workers. Understanding the circumstances of the elderly who die alone is beneficial to countries facing an aging society with weakened family or community structures, and who hope for better support for the elderly.

In the field of Forensic Medicine the number of unidentified cadavers has increased due to natural disasters and international terrorism. The age estimation is very important for identification of the victims. The degree of sagittal closure is one of such age estimation methods. However it is not widely accepted as a reliable method for age estimation. In this study, we have examined whether measuring impedance value (z-values) of the sagittal suture of the skull is related to the age in men and women and discussed the possibility to use bone impedance for age estimation. Bone impedance values increased with aging and decreased after the age of 64.5. Then we compared age estimation through the conventional visual method and the proposed bone impedance measurement technique. It is suggested that the bone impedance measuring technique may be of value to forensic science as a method of age estimation.

Fine needle aspiration (FNA) and core needle biopsy (CNB) are recognized to be safe, useful, and inexpensive diagnostic tools for the evaluation of thyroid nodules. However, complications can arise during the procedure, albeit rarely and typically minor in nature. We report here an unusual fatal case of massive hematoma of the neck after FNA and CNB that may have caused airway obstruction. A 68-year-old Japanese woman underwent both procedures and was found dead at home later the same day. Although severe complications of FNA or CNB such as major bleeds or deaths are rarely reported, clinicians and forensic pathologists should be cognizant that complications can arise.

Progestin/estrogen oral contraceptives have some side effects, including venous thromboembolism. To alleviate side effects, improvements have been made to low-dose oral contraceptives, including reductions in the amount of estrogen and/or changes the type of progestin. A compound drug containing 3mg drospirenone and 20μg ethinylestradiol (DRSP/EE20, YAZ®) was released in overseas markets in 2006, and in Japan in 2010 as a newly developed low-dose medicines. This drug is expected to have lower side effects. We received a medicolegal autopsy case of a young woman who had been prescribed YAZ for dysmenorrhea for 17months. The autopsy revealed a blood clot in her pulmonary artery bifurcation. Blood screening by ultra-performance liquid chromatography-mass spectrometry analysis did not detect any medicinal toxicants. However, from police investigations, it is strongly believed that she had been taking YAZ. Therefore we performed a single ion resolution mode assay and detected DRSP. A quantitative analysis revealed 32.3ng/mL of DRSP. As no other cause of the pulmonary thromboembolism was evident, we consider YAZ as the likely cause of the pulmonary thromboembolism. Recent reports from the past few years suggest a higher risk of venous thromboembolism with DRSP/EE20 than earlier progestin/estrogen oral contraceptives. Comparing the risk associated with DRSP/EE20 and DRSP/EE30, one report found no differences and another report showed DRSP/EE20 was associated with a higher risk than DRSP/EE30. No cases of thrombosis caused by progestin alone have been reported. But comparing the risk between DRSP/EE20 and other progestins/EE20, two studies reported DRSP/EE20 had a higher risk than other progestins/EE20. The incidence of venous thromboembolism is highest in the first year of use and decreases thereafter. Because DRSP/EE20 has been on the market for only a couple of years, it is necessary for clinicians to use the drug carefully and accumulate more side-effect data. It is important for forensic scientists to confirm all of the prescribed drugs in autopsy cases, search the risks of identified drugs, particularly new drugs, and provide relevant case information in a timely manner.

BACKGROUND: According to the dual structure model, the modern Japanese ethnic population consists of a mixture of the Jomon people, who have existed in Japan since at least the New Stone Age, and the Yayoi people, who migrated to western Japan from China around the year 300 bc Some reports show that the Yayoi are linked to a mutation of the aldehyde dehydrogenase 2 gene (ALDH2). Recent viral studies indicate two major groups found in the Japanese population: a group with the CY genotype JC virus (JCV) and a group with the MY genotype JCV. It is unclear whether either genotype of the JC virus is related to the Jomon or Yayoi. In this study, we attempted to detect JCV genotypes and ALDH2 mutations from the DNA of 247 Japanese urine samples to clarify the relationship between the dual structure model and the JCV genotype through ALDH2 mutation analysis and JCV genotyping. FINDINGS: The ALDH2 polymorphism among 66 JC virus-positive samples was analyzed, and it was found that the ALDH2 variant is significantly higher in the population with CY genotype JCV (51.5 %) than in the population with the MY genotype (24.2 %) (p < 0.05). CONCLUSION: From these findings, it may be inferred that the ALDH2 mutation, which is related to the Yayoi, is related to CY genotype JCV. When the Yayoi migrated to the Japanese archipelago, they brought the ALDH2 mutation as well as the CY genotype JCV.

It remains unanswered whether and how intraoperative frozen section analysis contributes to the surgical margin status on radical prostatectomy specimens. We aimed to determine whether frozen section analysis during radical prostatectomy reduces the incidence of positive surgical margins. We retrospectively analyzed a consecutive series of patients undergoing robot-assisted laparoscopic radical prostatectomy performed at our institution between 2004 and 2011. We identified 2608 cases, including 1128 (43.3%) where intraoperative frozen section analysis was performed to assess surgical margins. Of the cases with positive (n = 60; 5.3%)/negative (n = 1029; 91.2%)/atypical or indeterminate (n = 39; 3.5%) frozen section analyses, 22 (36.7%)/83 (8.1%)/4 (10.3%) were found to have positive surgical margins on radical prostatectomy specimens, respectively. Thus, 109 (9.7%) of 1128 cases with frozen section analysis had positive surgical margins, compared with 163 (11.0%) of 1480 cases with no frozen section analysis (P = .264). When the patients were subgrouped by histopathologic characteristics, frozen section analysis led to a considerable reduction in the rate of positive surgical margins in cases with biopsy Gleason score 7 (12.4% → 8.7%; P = .087)/8 (28.6% → 16.3%; P = .048)/≥7 (15.3% → 10.1%; P = .012) tumor or pT3b (36.6% → 23.2%; P = .075)/≥pT3b (38.1% → 25.4%; P = .091) disease. Multivariate analysis further revealed that performing frozen section analysis in biopsy Gleason score 7 or higher tumors was an independent predictor of negative surgical margins (odds ratio, 0.61; P = .018). In addition, frozen section analysis of the distal urethra or apex of the prostate (7.5%, P = .035) as well as multiple negative frozen section analyses (≥2: 6.2%, P = .001; ≥4: 2.2%, P = .007) correlated with significantly lower rates of positive surgical margin, compared with no frozen section analysis. Overall, intraoperative frozen section analysis did not dramatically change surgical margin status of radical prostatectomy. Nonetheless, it could be useful in preventing incomplete tumor resection, especially in men with high-grade (Gleason score ≥7) tumor at the apex.

本研究課題は令和元年度から２年度までの２ヶ年計画であったが、コロナ禍の影響により１年延長し、今年度はその３年目であった。今年度は具体的には、フィールドワークから国民生活基礎調査等の全国レベルの行政統計を入手し、家庭内の不慮の事故の危険因子を分析することとした。令和３年３月に無事、国民生活基礎調査データの提供を厚生労働省から受け,同年８月にはさらに、最新版のデータを追加で入手することができた。加えて、国民健康・栄養調査のデータも併せて、厚生労働省に利用申請中である。令和３年度は、このようにフィールドワークから国の基幹統計データ分析へと大きく方針変更を行ったため、そのデータ入手に大半のエフォートを注力することとなった。そのため、本研究をさらに１年間延長し、４年目の令和４年度はその分析を集中的に進めるとともに、原著論文の国際誌への投稿、国際学会での発表を予定している。なお、既に現時点で、複数の国際誌への投稿自体は完了している。特に、家庭内の不慮の事故の危険因子となりやすい、飲酒行動関連の分析を優先して進めている。また、所属機関医学部の臨床各教室とも連携を進め、臨床と基礎医学の架橋的研究成果も挙げており、一部は令和４年３月に国際誌（Journal of Cardiology）に掲載された。なお、今後は論文採択が判明し次第、その結果を地域自治体の健康福祉施策にフィードバックすべく、行政との連携も深めていく予定である。