Publications by authors named "Yasuhito Fujii"

Background: COVID-19 has become widespread in Japanese children. However, the impact of varying immunization coverage on the seroprevalence of SARS-CoV-2 in children is unknown.

Methods: We examined the SARS-CoV-2 antibody in children aged 0 to 18 who were hospitalized at a university hospital from June 2020 through May 2023.

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Low testosterone concentrations are associated with disrupted sleep, and high levels of cortisol, which is elevated in response to stress, lead to insomnia. This study aimed to investigate the associations of testosterone and cortisol concentrations with sleep quality and to examine potential interactions between them in Japanese working men. This study was a cross-sectional design, and testosterone and cortisol concentrations in blood were the exposure variables and sleep parameters were the outcome variables.

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Objective: The purpose of the study was to investigate the association between andropause symptoms and sickness absence in Japanese male workers over 2 years.

Methods: A baseline survey asking about andropause symptoms, along with blood sampling for testosterone level, was conducted in June 2009. A total of 418 men (mean age = 52.

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Purpose: This study aimed to investigate the association between serum levels of cortisol and dehydroepiandrosterone sulfate (DHEA-s) and sickness absence over 2 years in Japanese male workers.

Method: A baseline survey including questions about health behavior, along with blood sampling for cortisol and DHEA-s, was conducted in 2009. In total, 429 men (mean ± SD age, 52.

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This study aimed to develop a new Acceptance of Selfishness at the Workplace Scale (ASWS) and to confirm Maslow's hypothesis of synergy: if both a sense of contribution and acceptance of selfishness at the workplace are high, workers are psychologically healthy. In a cross-sectional study with employees of three Japanese companies, 656 workers answered a self-administered questionnaire on paper completely (response rate = 66.8%).

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Purpose: The purpose of this longitudinal study was to ascertain if changes in job demands modify associations between changes in testosterone levels and andropause symptoms in male Japanese workers.

Method: A baseline survey including job demands and the Aging Males' Symptoms scale, lifestyle factors, and blood levels of testosterone was conducted in 2007. Among 192 men (mean age ± SD 52.

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The purpose of this prospective study was to investigate the effect of the patterning of workplace bullying and harassment over two time points (chronic, remission, onset, and never) on psychological and physical stress reactions. The subjects were 543 workers at welfare facilities for the elderly in Japan who completed a self-administered questionnaire at Time 1 (from August to September, 2009) and at Time 2 (from September to October, 2011). Workplace bullying and harassment were assessed using the Negative Acts Questionnaire (NAQ).

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Background: Although serum cortisol is a widely accepted index of stress levels, associations between job stress and cortisol levels have been inconsistent. Individual differences in personality traits were discussed as one compelling explanation for this discrepancy. Agentic-communal personality traits have been examined as possible predictive factors for psychological stress.

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The purpose of this study was to assess the validity and reliability of the Sense of Contribution Scale (SCS), a newly developed, 7-item questionnaire used to measure sense of contribution in the workplace. Workers at 272 organizations answered questionnaires that included the SCS. Because of non-participation or missing data, the number of subjects included in the analyses for internal consistency and validity varied from 1,675 to 2,462 (response rates 54.

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Objective: The present study investigated whether job demands modify the association between low levels of testosterone and andropause symptoms.

Study Design: Participants were Japanese middle-aged workers in a middle-size company. Blood samples were drawn to determine serum levels of testosterone.

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Objective: The purpose of this study was to assess whether workplace bullying mediates between job strain, evaluated by the job demand-control model, and symptoms of depression and sleep disturbance.

Methods: The subjects in this cross-sectional study were recruited from all the workers (N=2,634) at 50 organizations in Japan. Due to missing data, the numbers of subjects included in the analyses varied from 1,646 to 2,062 (response rates varied from 62.

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Objectives: Interest in workplace bullying and harassment has been increasing in Japan. At present, the Negative Acts Questionnaire (NAQ) is one of the most frequently used questionnaires for assessing these issues. The purpose of this study was to develop a Japanese version of the NAQ.

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We conducted a randomized controlled trial involving Japanese junior college students aimed at investigating the effects of a single session of alcohol health education concerning the effects of alcohol, alcohol-related health problems, and drinking behavior. Students were randomly assigned to an intervention (n=38) or a control group (n=33). The intervention group attended a 90-minute alcohol health education session that included demonstration of an ethanol patch test, watching videos, and a lecture by an ex-alcoholic.

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