Higher-Order Structure of Adeno-Associated Virus Serotype 8 by Hydrogen/Deuterium Exchange Mass Spectrometry.

The higher-order structure (HOS) is a critical quality attribute of recombinant adeno-associated viruses (rAAVs). Evaluating the HOS of the entire rAAV capsid is challenging because of the flexibility and/or less folded nature of the VP1 unique (VP1u) and VP1/VP2 common regions, which are structural features essential for these regions to exert their functions following viral infection. In this study, hydrogen/deuterium exchange mass spectrometry (HDX-MS) was used for the structural analysis of full and empty rAAV8 capsids. We obtained 486 peptides representing 85% sequence coverage. Surprisingly, the VP1u region showed rapid deuterium uptake even though this region contains the phospholipase A2 domain composed primarily of α-helices. The comparison of deuterium uptake between full and empty capsids showed significant protection from hydrogen/deuterium exchange in the full capsid at the channel structure of the 5-fold symmetry axis. This corresponds to cryo-electron microscopy studies in which the extended densities were observed only in the full capsid. In addition, deuterium uptake was reduced in the VP1u region of the full capsid, suggesting the folding and/or interaction of this region with the encapsidated genome. This study demonstrated HDX-MS as a powerful method for probing the structure of the entire rAAV capsid.

Factors Associated With Work Engagement of Nurses During the Fifth Wave of the COVID-19 Pandemic in Japan: Web-Based Cross-Sectional Study.

BACKGROUND: The COVID-19 pandemic has brought to light the prevalence of mental health issues among nurses. Work engagement (WE) is a concept that describes work-related positive psychological states and is of importance within mental health measures. There is, however, a lack of research on factors associated with the WE of nurses during the COVID-19 pandemic. OBJECTIVE: We aimed to determine which factors are associated with WE among nurses during the COVID-19 pandemic using the job demands-resources (JD-R) model as a framework. METHODS: A web-based cross-sectional survey was conducted among nurses working in acute care and psychiatric institutions in the prefectures of Chiba and Tokyo in Japan. The survey period occurred between August 8 and September 30, 2021, during a time when the number of patients with a positive COVID-19 infection increased. The 3-item version of the Utrecht Work Engagement Scale (UWES-3) was used to measure WE. Factors such as age, gender, years of experience, affiliated ward, COVID-19-related stress, financial rewards from the government and hospital, encouragement from the government and patients, and workplace social capital were assessed. A total of 187 participants were included in the final analysis. Multiple regression analysis was performed to examine the factors related to WE. Partial regression coefficients (B), 95% CI, and P values were calculated. RESULTS: The mean overall score for the UWES-3 was 3.19 (SD 1.21). Factors negatively associated with UWES-3 were COVID-19-related stress on work motivation and escape behavior (Β -0.16, 95% CI -0.24 to -0.090; P<.001), and factors positively associated with UWES-3 were affiliation of intensive care units (Β 0.76, 95% CI 0.020-1.50; P=.045) and financial rewards from the government and hospital (Β 0.40, 95% CI 0.040-0.76; P=.03). CONCLUSIONS: This study examined factors related to WE among nurses during the COVID-19 pandemic using the JD-R model. When compared with findings from previous studies, our results suggest that nurses' WE was lower than before the COVID-19 pandemic. Negative motivation and escape behaviors related to COVID-19 were negatively associated with WE, while there were positive associations with financial rewards from the government and hospital and affiliation with an intensive care unit. Further research into larger populations is needed to confirm these findings.

Optimization of Flow Imaging Microscopy Setting Using Spherical Beads with Optical Properties Similar to Those of Biopharmaceuticals.

Flow imaging microscopy (FIM) is widely used to characterize biopharmaceutical subvisible particles (SVPs). The segmentation threshold, which defines the boundary between the particle and the background based on pixel intensity, should be properly set for accurate SVP quantification. However, segmentation thresholds are often subjectively and empirically set, potentially leading to variations in measurements across instruments and operators. In the present study, we developed an objective method to optimize the FIM segmentation threshold using poly(methyl methacrylate) (PMMA) beads with a refractive index similar to that of biomolecules. Among several candidate particles that were evaluated, 2.5-µm PMMA beads were the most reliable in size and number, suggesting that the PMMA bead size analyzed by FIM could objectively be used to determine the segmentation threshold for SVP measurements. The PMMA bead concentrations measured by FIM were highly consistent with the indicative concentrations, whereas the PMMA bead size analyzed by FIM decreased with increasing segmentation threshold. The optimal segmentation threshold where the analyzed size was closest to the indicative size differed between an instrument with a black-and-white camera and that with a color camera. Inter-instrument differences in SVP concentrations in acid-stressed recombinant adeno-associated virus (AAV) and protein aggregates were successfully minimized by setting an optimized segmentation threshold specific to the instrument. These results reveal that PMMA beads can aid in determining a more appropriate segmentation threshold to evaluate biopharmaceutical SVPs using FIM.

Relationships Between Childhood Bullying/Domestic Violence Experience and Insomnia among Employees in Japan.

OBJECTIVE: Traumatic childhood experiences such as domestic violence and bullying have been reported to be associated with insomnia in adulthood. However, little evidence is available for the long-term effects of childhood adversity on workers' insomnia worldwide. Our objective was to examine whether childhood experiences of bullying and domestic violence are associated with insomnia in workers in adulthood. METHODS: We used survey data from a cross-sectional study of the Tsukuba Science City Network in Tsukuba City, Japan. Workers aged 20 to 65 years (4509 men and 2666 women) were targeted. Binomial logistic regression analysis was performed with the Athens Insomnia Scale as the objective variable. RESULTS: Binomial logistic regression analysis showed that childhood bullying and domestic violence experience of childhood bullying and domestic violence were associated with insomnia. As for the experience of domestic violence, the higher the time of experience, the higher the odds ratio of insomnia. CONCLUSIONS: It may be useful to focus on childhood traumatic experiences regarding insomnia in workers. In the future, objective sleep time and sleep efficiency should be evaluated using an activity meter and other methods to verify the effects of bullying and domestic violence experiences.

A high sense of coherence can mitigate suicidal ideation associated with insomnia.

BACKGROUND: The present study aimed to investigate whether insomnia is associated with suicidal ideation (SI) among Japanese workers by conducting a multi-level analysis with sense of coherence (SOC) as a random effect. PARTICIPANTS AND PROCEDURE: A cross-sectional survey was conducted among 19,481 workers in Tsukuba, Japan. Data from 7,175 participants aged 20-65 years were included in the analysis. The Athens Insomnia Scale (AIS) was used as the independent variable, and SI over the past year was used as the dependent variable. SOC was measured using the five-point SOC-13 scale, and socioeconomic and health factors were investigated as covariates. Participants were divided into three groups (low, medium, and high) based on their SOC scores. Multilevel logistic regression analysis was performed to calculate odds ratios (OR) and 95% confidence intervals (95% CI). RESULTS: In the high-SOC group, only one person had SI. In a multi-level logistic analysis that excluded the high SOC group, insomnia was found to be associated with SI (OR = 2.26, 95% CI [1.75, 2.93]). Furthermore, the AIS sub-items "Final awakening earlier than desired" (OR = 1.26, 95% CI [1.05, 1.50]) and "Sense of well-being during the day" (OR = 1.63, 95% CI [1.34, 1.99]) were associated with SI. 8.95% or 11% of the variation in the presence or absence of SI was found to be explained by differences between SOC groups. CONCLUSIONS: The study highlights that insomnia is associated with SI, and that high SOC may reduce SI even under insomnia. Future longitudinal studies are needed to confirm whether high SOC reduces SI due to insomnia.

Relationships between sleep efficiency and lifestyle evaluated by objective sleep assessment: SLeep Epidemiology Project at University of Tsukuba.

Objectively measured sleep efficiency has recently been shown to be associated with health problems. Although several factors have previously been reported to be associated with sleep efficiency, most of these studies were conducted on older or younger adults, and the factors associated with sleep efficiency in healthy workers remain unknown. The aim of this study was to investigate the relationship between sleep efficiency and lifestyle factors using sleep measurement data recorded by an activity meter worn by workers. In total, 693 workers (male, 43.6%; mean age, 42.7 ± 11.3 years) were recruited from five offices in 2017. Sleep was measured over the period of 1 week by actigraphy. Workers' attributes, lifestyle habits, and occupational stress were identified using a questionnaire, and the association of sleep efficiency with lifestyle, occupational stress, and attributes was explored by logistic regression analysis. A logistic regression analysis using attributes and occupational stress as adjustment variables revealed that "longer sleeping hours on weekends than on weekdays" [odds ratios (OR), 0.66; 95% confidence interval (CI), 0.47-0.94], "water ingestion at bedtime" [OR, 2.09; 95% CI, 1.28-3.41], and "smartphone use at bedtime" [OR, 1.90; 95% CI, 1.28-2.83] were associated with decreased sleep efficiency. This study found that lifestyle habits were associated with sleep efficiency among workers. It is necessary to verify whether intervention in these lifestyle habits would contribute to the improvement of sleep efficiency in future studies.

Prevalence, characteristics, and psychological outcomes of workplace cyberbullying during the COVID-19 pandemic in Japan: a cross-sectional online survey.

BACKGROUND: The rapid introduction of teleworking due to the coronavirus disease 2019 pandemic has led to concerns about increases in cyberbullying (CB) worldwide. However, little is known about workplace CB in non-Western countries. The first objective was to clarify the prevalence and characteristics regarding workplace CB victimization in Japan. The second objective was to demonstrate the psychological outcomes of CB victimization in combination with traditional bullying (TB). METHODS: We conducted an anonymous, cross-sectional, Internet-based survey targeting regular employees in Japan (N = 1200) in January 2021. We investigated CB victimization using the Inventory of Cyberbullying Acts at Work and TB victimization by using the Short Negative Act Questionnaire. Possible explanatory factors for TB/CB victimization were sociodemographic variables, personality trait, chronic occupational stress, organizational climate, and gratitude at work. We also measured psychological distress, insomnia, and loneliness to assess adverse effects of workplace bullying. Two-step cluster analysis was used in determining the patterns combined with TB and CB victimization. Hierarchical binomial logistic regression analysis was used. RESULTS: In total, 8.0% of employees reported experiencing CB on a weekly basis. CB victimization was associated with younger age, managerial position, higher qualitative workload, and active information dissemination via the Internet, and frequency of teleworking. Three clusters based on TB and CB victimization patterns were identified: those who belong to the first cluster suffered neither from TB and CB (81.0%), the second cluster suffered only from TB (14.3%), and the third cluster suffered from both TB and CB (4.8%). The third cluster exhibited higher odds ratios (ORs) and 95% confidence intervals (CIs) for psychological distress (OR = 12.63, 95% CI = 4.20-38.03), insomnia (OR = 6.26, 95% CI = 2.80-14.01), and loneliness (OR = 3.24, 95% CI = 1.74-6.04) compared to the first cluster. CONCLUSIONS: These findings firstly clarify the prevalence and correlated factors of CB victimization among employees in Japan. Further, we showed that psychological wellbeing can be impaired by the coexistence of TB and CB. Our research could be the first step to develop the effective countermeasures against workplace CB.

Ibaraki's Amabie-chan usage and its association with infection prevention behavior and fear of COVID-19: a cross-sectional preliminary survey of the Tsukuba Salutogenic Occupational Cohort Study.

BACKGROUND: Ibaraki's Amabie-chan is a COVID-19 infection control system unique to Ibaraki prefecture, Japan. It requires residents to register each time they visit events, commercial facilities, and restaurants. The number of registrations has been limited, and its function alerting about people positive for COVID-19 infection seems not to be working. Nevertheless, registration with the system might have some impact on the user's behavior. In the current preliminary survey, the possible impact of Ibaraki's Amabie-chan on infection prevention behavior and fear of COVID-19 was investigated. METHODS: A cross-sectional, web-based, anonymous, and self-administered survey was conducted at two workplaces in Tsukuba Science City, Ibaraki, Japan. The first survey was conducted at one of the workplaces in November 2020, and the second survey, at the other workplace in February 2021. Variables of interest were sex, age group, marital status, employment status, Ibaraki's Amabie-chan use, COVID-19 Contact-Confirming Application use, ten items of infection prevention behaviors, and fear of COVID-19. Hierarchical linear regression analysis was performed. RESULTS: In both surveys, use of Ibaraki's Amabie-chan was significantly associated with COCOA use and with "physical condition management such as body temperature measurement." No association was found with other infection prevention behaviors or with fear of COVID-19. CONCLUSIONS: Our findings did not provide sufficient evidence for the effectiveness of Ibaraki's Amabie-chan in regard to users' infection control behavior. Further detailed study is needed to investigate the effectiveness in terms of infection prevention and the cost-effectiveness of Ibaraki's Amabie-chan.

Morning preference is associated with subjective happiness among Japanese female workers: A moderation analysis by sleep characteristics from the SLEPT study.

Research on mental health in working populations has predominantly focussed on negative outcomes, while studies on the positive aspects of life remain very limited, especially in Japan. Although morningness has recently been considered a factor for being happy, the role of sleep characteristics as it relates to the association between morningness and happiness has not been substantiated. The aim of this study is to investigate the associations between diurnal preference and level of subjective happiness in healthy, full-time, daytime workers in Japan. We also tested the moderation effect of sleep parameters on the relationship between diurnal preference and subjective happiness. This is an exploratory analysis from the cross-sectional data of the SLeep Epidemiology Project at the University of Tsukuba (SLEPT Study). Subjective happiness was evaluated using a single-item question. Diurnal preference was assessed using the Morningness-Eveningness Questionnaire (MEQ), in which higher scores indicate greater tendency to have morning preference. The participants underwent assessment of sleep parameters for 7 consecutive days using a waist-worn actigraphy device and kept a sleep diary. Sleep parameters investigated were subjective sleep quality, sleep disturbance, daytime sleepiness, weekend oversleep, total sleep time, sleep onset time, wake time, and sleep efficiency. A total of 205 males (average 42.6 ± 10.4 years) and 272 females (41.1 ± 9.8 years) were eligible for analysis. Hierarchical liner regression analysis was used to show the relationships of subjective happiness with MEQ score, and the sleep parameters. Further, moderation analysis was conducted by adding the interaction between MEQ score and the sleep parameters. After adjusting for age, psychological distress, self-rated health, and occupational stress, we found that subjective happiness was significantly associated with higher MEQ score and sleep efficiency but only in female. The moderating role of sleep parameters was not found. We discussed the implications of the obtained results and a possible strategy to maintain and improve subjective happiness of female workers who have evening preference.

Comparison of predicted psychological distress among workers between artificial intelligence and psychiatrists: a cross-sectional study in Tsukuba Science City, Japan.

OBJECTIVES: Psychological distress is a worldwide problem and a serious problem that needs to be addressed in the field of occupational health. This study aimed to use artificial intelligence (AI) to predict psychological distress among workers using sociodemographic, lifestyle and sleep factors, not subjective information such as mood and emotion, and to examine the performance of the AI models through a comparison with psychiatrists. DESIGN: Cross-sectional study. SETTING: We conducted a survey on psychological distress and living conditions among workers. An AI model for predicting psychological distress was created and then the results were compared in terms of accuracy with predictions made by psychiatrists. PARTICIPANTS: An AI model of the neural network and six psychiatrists. PRIMARY OUTCOME: The accuracies of the AI model and psychiatrists for predicting psychological distress. METHODS: In total, data from 7251 workers were analysed to predict moderate and severe psychological distress. An AI model of the neural network was created and accuracy, sensitivity and specificity were calculated. Six psychiatrists used the same data as the AI model to predict psychological distress and conduct a comparison with the AI model. RESULTS: The accuracies of the AI model and psychiatrists for predicting moderate psychological distress were 65.2% and 64.4%, respectively, showing no significant difference. The accuracies of the AI model and psychiatrists for predicting severe psychological distress were 89.9% and 85.5%, respectively, indicating that the AI model had significantly higher accuracy. CONCLUSIONS: A machine learning model was successfully developed to screen workers with depressed mood. The explanatory variables used for the predictions did not directly ask about mood. Therefore, this newly developed model appears to be able to predict psychological distress among workers easily, regardless of their subjective views.

Differences in psychological distress between managers and non-managers in female workers: a cross-sectional study in Tsukuba Science City, Japan.

The Japanese government has made efforts towards the advancement of women into society; thereby, the proportion of female managers has been increasing. Recent reports have shown that managers tend to be in poor health condition. However, little research has been conducted to examine the psychological health of female managers. Therefore, the aim of our study was to reveal the difference of psychological distress by occupational position in female workers with focus on occupational stress. A cross-sectional survey was conducted in 2017 via an anonymous, self-administered questionnaire distributed to workers in Tsukuba City, Japan. Student unpaired t test was used to compare occupational stress and psychological distress by occupational position. Binomial logistic regressions were used to analyze factors that affect psychological distress separately in managers and non-managers. A total of 1543 women (168 managers, 1375 non-managers) were analyzed. Managers showed higher occupational stress but lower psychological distress than non-managers. Problems in interpersonal relationships was positively associated with psychological distress, whereas occupation as a researcher/academic was negatively associated with psychological distress in managers. Mental workload and problems in interpersonal relationships were positively associated with psychological distress, whereas reward from work and support were negatively associated with psychological distress in non-managers. Managers and non-managers both showed an association between psychological distress and problems of interpersonal relationships. Non-managers might have higher psychological distress due to lower reward from work. It is important to increase reward from work and to develop female workers' interpersonal skills in order to reduce the psychological distress of female workers.

Relationships between insomnia, long working hours, and long commuting time among public school teachers in Japan: a nationwide cross-sectional diary study.

OBJECTIVES: The present study aimed to clarify the prevalence and risk factors of insomnia among public school teachers in Japan by examining the relationships between working hours, commuting time, and insomnia. Time spent on work activities among teachers with insomnia was also investigated. METHODS: This study was a secondary analysis of data obtained in a 2016 survey of working conditions among public elementary/junior high school teachers in Japan. A total of 11,390 teachers (women: 47.4%, average age: 42.2 ± 11.3 years) were selected for analysis. The relationships between working hours, commuting time, and insomnia were evaluated using a binomial logistic regression model. The primary outcome was insomnia, defined by a score of ≥6 on the Athens Insomnia Scale. Explanatory factors were working hours/week, commuting time/day, six subscales of occupational stress, age group, presence of children, type of job, type of the school, and the urbanicity of the school. RESULTS: In total, 41.7% of men and 44.0% of women were classified into the insomnia group. The insomnia group spent more time preparing for lectures, and a significant association was observed between insomnia and long working hours and commuting time. Results of multivariate logistic regression analysis showed that long working hours, long commuting time, and urbanicity of the school were statistically significantly associated with insomnia. CONCLUSIONS: Insomnia is common among public school teachers in Japan. Our findings suggest the importance of reducing the time spent on working to prevent insomnia.

School Ijime (Bullying) Experience Is a Possible Risk Factor for Current Psychological Distress among Science City Workers: A Cross-Sectional Study in Tsukuba, Japan.

Early-life adversities are considered to have long-term impact on health. There have been many studies regarding the experience of being bullied and its harmful psychological influence, but such influence on workers remains to be investigated in Japan. We therefore aimed to examine the prevalence of workers with experiences of being bullied or bullying others during childhood and adolescence and to clarify the relation between those experiences and current psychological distress. A cross-sectional study using an anonymous self-report web questionnaire was conducted in November 2017. The study population was 19,481 workers belonging to the Tsukuba Science City Network, and we analyzed the data of 6,015 participants (3,715 men and 2,300 women, aged between 20 years and 59 years). The percentages of participants with experiences of being bullied were 51.5% for men and 56.2% for women; those with experiences of bullying others were 36.5% of men and 29.4% of women. Relations between experiences of bullying and psychological distress were assessed using Chi-squared tests. Logistic regression analyses with psychological distress as an objective variable and experiences of bulling as explanatory variables were performed using those who had no bulling experiences as control. In both men and women, experiences of being bullied were significantly associated with psychological distress after adjustment socioeconomic factors (the odds ratios were 1.26 for men (95% CI = 1.05-1.52) and 1.72 for women (95% CI = 1.39-2.13)). Consideration of past social experiences, such as being bullied, is useful for mental health management among workers reporting psychological distress.

Association between flourishing mental health and occupational stress among workers of Tsukuba Science City, Japan: a cross-sectional study.

BACKGROUND: Flourishing, defined as the coexistence of hedonic and eudaimonic well-being, is the most favorable end of the mental health spectrum. A growing body of evidence has demonstrated the association between flourishing mental health and favorable work-related outcomes. However, epidemiology of flourishing mental health is scarce in Japan. Moreover, the relationship between flourishing mental health and occupational stress has not been elaborated. Therefore, the aim of this study was to elucidate (1) the prevalence of flourishing mental health and (2) the association between flourishing mental health and occupational stress among Japanese workers. METHODS: The present survey was conducted in from February to March 2017 via an anonymous, self-administered, and web-based questionnaire among workers in Tsukuba Science City, Japan. Mental Health Continuum Short Form was used to assess flourishing mental health. We performed binomial logistic regression analyses to calculate the adjusted odds ratios (AOR) and 95% confidence intervals (CI) of occupational stress for flourishing mental health, controlling for sociodemographic factors. RESULTS: A total of 7012 respondents (4402 men, 2610 women) were analyzed. The overall prevalence of flourishing mental health among the respondents was 12.4%. Full-time (permanent) workers were less likely to be flourishing. Reward from work (AOR = 2.34, 95% CI = 2.04-2.68), support from colleagues and superiors (AOR = 1.67, 95% CI = 1.44-1.94), and workload (AOR = 1.19, 95% CI = 1.05-1.36) were positively associated with flourishing mental health, whereas mental workload (AOR = 0.65, 95% CI = 0.57-0.75) was inversely associated with flourishing mental health. CONCLUSIONS: The findings of the present study shed light on the association between flourishing mental health and occupational stress.

Non-Regular Employment Status Is Associated with Psychological Distress among Young Researchers: A Cross-Sectional Study in Tsukuba, Japan.

Non-regular employment is increasing and its mental health impact is a globally important problem. In Japan, non-regularly employed researchers are increasing, especially within young age groups, because employment quotas were not sufficiently expanded against rapid increasing number of doctorate holders. It is therefore important to understand the relationship between non-regular employment and mental health. The significance of our research is to contribute to the improvement of researchers' mental health by clarifying the influence of employment status on psychological distress. We conducted a cross-sectional, web-based survey in 2017 via an anonymous, self-administered questionnaire distributed to workers in Tsukuba Science City, Japan. The survey questionnaire items included employment status, psychological distress, occupational stress, sex, age, and income. We analyzed 2,762 valid responses in two categories (1,850 regular employment, 912 non-regular employment) and two subcategories based on age according to the definition of "young researcher" by the Ministry of Health, Labor and Welfare (20-39 years vs. 40-59 years). Psychological distress was defined as a total K6 score of 5 or greater. Binomial logistic regression was used to calculate odds ratios and 95% confidence intervals for psychological distress. Non-regular employment was significantly associated with psychological distress in the age 20-39 group but not in the age 40-59 group. At the age 20-39 group, a negative association was shown between psychological distress and reward from work (i.e., pride in their job, ability utilization, and sense of accomplishment). Support to increase psychological work rewards may be important in reducing psychological distress for young non-regularly employed researchers.

Relationship between workplace social capital and suicidal ideation in the past year among employees in Japan: a cross-sectional study.

BACKGROUND: A growing body of evidence has demonstrated the associations between social capital and health. In residential or geographical areas, social capital has attracted attention for its protective effects against suicide. However, to this date, the relationship between social capital and suicidal ideation is not fully elaborated in the occupational setting. Therefore, the aim of the present study was to examine the association between workplace social capital and suicidal ideation in the past year among employees in Japan. METHODS: A cross-sectional, web-based survey was conducted in February/March 2017 via an anonymous self-administered questionnaire distributed to workers in Tsukuba Science City, Japan. Binomial logistic regressions were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for suicidal ideation in the past year, controlling for age group, marital status, educational attainment, and annual household income. The results were shown stratified by sex and occupation. RESULTS: In total, 7255 of 19,481 workers responded, out of which we could analyze 6325 responses (4030 men, 2295 women). The prevalence of suicidal ideation in the past year was 5.9% for men and 7.8% for women. Low workplace social capital was statistically significantly associated with suicidal ideation both for men (OR = 2.57, 95% CI = 1.72-3.83) and for women (OR = 1.75, 95% CI = 1.15-2.66), compared with high workplace social capital after controlling for socioeconomic factors. CONCLUSION: Higher workplace social capital was associated with a reduced risk of suicidal ideation in the past year. Promoting workplace social capital could contribute to preventing suicide among employees in Japan.