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Introduction: Brain age gap (BAG), defined as the difference between MRI-predicted 'brain age' and chronological age, can capture information underlying various neurological disorders. We investigated the pathophysiological significance of the BAG across neurodegenerative disorders., Methods: We developed a brain age estimator using structural MRIs of healthy-aged individuals from one cohort study. Subsequently, we applied this estimator to people with Alzheimer's disease spectra (AD) and Parkinson's disease (PD) from another cohort study. We investigated brain sources responsible for BAGs among these groups., Results: Both AD and PD exhibited a positive BAG. Brain sources showed overlapping, yet partially segregated, neuromorphological differences between these groups. Furthermore, employing with t-distributed stochastic neighbor embedding on the brain sources, we subclassified PD into two groups with and without cognitive impairment., Discussion: Our findings suggest that brain age estimation becomes a clinically relevant method for finely stratifying neurodegenerative disorders., Highlights: Brain age estimated from structure MRI data was greater than chronological age in patients with Alzheimer's disease/mild cognitive impairment or Parkinson's disease.Brain regions attributed to brain age estimation were located mainly in the fronto-temporo-parietal cortices but not in the motor cortex or subcortical regions.Brain sources responsible for the brain age gaps revealed roughly overlapping, yet partially segregated, neuromorphological differences between participants with Alzheimer's disease/mild cognitive impairment and Parkinson's disease.Participants with Parkinson's disease were subclassified into two groups (with and without cognitive impairment) based on brain sources responsible for the brain age gaps., Competing Interests: The authors declare no conflicts of interest. Author disclosures are available in the Supporting Information., (© 2025 The Author(s). Alzheimer's & Dementia: Diagnosis, Assessment & Disease Monitoring published by Wiley Periodicals, LLC on behalf of Alzheimer's Association.)

Large-scale population cohort studies that collect genomic information are tasked with returning an assessment of genetic risk for hereditary cancers to participants. While several studies have applied to return identified genetic risks to participants, comprehensive surveys of participants' understanding, feelings, and behaviors toward cancer risk remain to be conducted. Here, we report our experience and surveys of returning genetic risks to 100 carriers of pathogenic variants for hereditary cancers identified through whole genome sequencing of 50 000 individuals from the Tohoku Medical Megabank project, a population cohort study. The participants were carriers of pathogenic variants associated with either hereditary breast and ovarian cancer (n = 79, median age=41) or Lynch syndrome (n = 21, median age=62). Of these, 28% and 38% had a history of cancer, respectively. We provided information on cancer risk, heritability, and clinical actionability to the participants in person. The comprehension assessment revealed that the information was better understood by younger (under 60 years) females than by older males. Scores on the cancer worry scale were positively related to cancer experiences and general psychological distress. Seventy-one participants were followed up at Tohoku University Hospital; six females underwent risk-reducing surgery triggered by study participation and three were newly diagnosed with cancer during surveillance. Among first-degree relatives of hereditary breast and ovarian cancer carriers, participants most commonly shared the information with daughters. This study showed the benefits of returning genetic risks to the general population and will provide insights into returning genetic risks to asymptomatic pathogenic variant carriers in both clinical and research settings., Competing Interests: Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Background: Natural disasters may have negative health effects on survivors. However, long-term observations on this are lacking. Therefore, this study investigated the association between the degree of housing damage caused by the Great East Japan Earthquake (GEJE) and all-cause mortality using the data from the cohort study conducted by the Tohoku Medical Megabank (TMM) Project in disaster-stricken areas., Methods: The community-based cohort study of the TMM Project which conducted a baseline survey from May 2013 to March 2016 collected data using questionnaires and blood and urine tests. The present large-scale prospective cohort study was a follow-up survey in which the degree of house damage and all-cause mortality were analysed using Cox proportional hazards regression, adjusting for sex, age and other potentially confounding variables. The degree of house damage was categorised into 'did not live in the disaster area', 'no damage', 'small-scale damage' and 'large-scale damage'. Among the 58 320 participants, 1763 deaths were confirmed during the follow-up which averaged 6.5 years., Results: The multivariate analysis showed a hazard ratio (95% CI) of 0.96 (0.82 to 1.13) for those who did not live in the disaster area, 0.98 (0.87 to 1.10) for small-scale damage and 0.98 (0.85 to 1.14) for large-scale damage, compared with no damage, but no significant association with all-cause mortality was observed., Conclusion: The results of this large-scale prospective cohort study of GEJE survivors showed no significant relationship between the degree of house damage and all-cause mortality. Further long-term follow-up studies are needed to examine the long-term health effects of natural disasters on survivors., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2025. No commercial re-use. See rights and permissions. Published by BMJ Group.)

Background: The primary prevention of atrial fibrillation (AF), which increases mortality through complications including stroke and heart failure, is important. Excessive salt intake and low potassium intake are risk factors for cardiovascular disease; however, their association with AF remains inconclusive. This study investigated the association between sodium- and potassium-related urinary markers and AF prevalence., Methods and Results: Data from the Tohoku Medical Megabank Project Community-based Cohort Study were used in this cross-sectional study. The urinary sodium-to-potassium (Na/K) ratio and estimated 24-h sodium and potassium excretion were calculated using spot urine samples and categorized into quartiles (Q1-Q4). The prevalence of AF was the primary outcome. Of the 26,506 participants (mean age 64.8 years; 33.2% males) included in this study, 630 (2.4%) had AF. Using Q1 as the reference group, the odds ratios for AF prevalence in Q4 were 1.35 (95% confidence interval [CI] 1.07-1.73) and 1.59 (95% CI 1.20-2.12) for 24-h estimated urinary Na/K ratio and estimated 24-h sodium excretion, respectively. Estimated 24-h potassium excretion was not associated with AF prevalence., Conclusions: AF prevalence was positively associated with the urinary Na/K ratio and estimated 24-h urinary sodium excretion, but not with estimated 24-h urinary potassium excretion. Although further prospective studies are warranted, the findings of this study suggest that salt intake may be a modifiable risk factor for AF.

Objective: This study aimed to identify structural changes in age-related curved hair (referred to as "YUGAMI" hair in Japanese) induced by cyclical extension using infrared (IR) spectroscopy coupled with chemometrics, such as multivariate curve resolution (MCR) and two-dimensional correlation spectroscopy (2DCOS)., Methods: The hair fibres were stretched at a strain level of 0.3-N, and this operation was counted as one cycle and was repeated 500 cycles. Every 25 cycles, IR spectra were obtained using an attenuated total reflection IR (ATR-IR) microscope. The spectra were analysed by MCR to investigate the structural changes of keratin protein inside of the hair. 2DCOS was conducted to investigate the genesis pathway of SO 3 H in the 1000-1150 cm -1 range and the change in the secondary structure of keratin protein of hair in the 1600-1700 cm -1 range., Results: For age-related curved hair, 0.3-N strain levels increased the CH 2 and C=O signals after 125 cycles and the SO 3 H signal after 225 cycles, but no architectural modifications were observed in straight hair. Two results were obtained from 2DCOS. One was cyclical extension increased the S-SO 3 H signal, followed by SO 3 H signal. The other in the 1600-1700 cm -1 range indicated an increase in the secondary structural motif and β-structure after the formation of SO 3 H., Conclusion: This study shows that the process of internal transformations can be split into three steps in age-related curved hair caused by cyclical extension. The first step is the surface transfer of internal lipids, and the second step is two distinct patterns of disulfide bond cleavage: C-S and S-S fission. The final step is further transformation of the unravelled α-helices into β-structures which occurs above roughly 225 stretched. Our findings can be an effective factor in care the increase of curvature by cyclical extension such as everyday grooming., (© 2025 Society of Cosmetic Scientists and the Société Française de Cosmétologie.)