Evaluating the relaxation effects of Shikuwasa (Citrus depressa Hayata) essential oil inhalation in young female adults: Study protocol for a randomised controlled trial.

Introduction: The essential oil of Shikuwasa (Citrus depressa Hayata) primarily contains limonene and γ-terpinene, which have potential applications in stress management and relaxation. However, the psychological or physiological relaxation effects of Shikuwasa essential oil on humans are still unknown. This study aims to investigate the short-term relaxation effects of Shikuwasa essential oil, one of the less-studied varieties, compared to inhaling odour-free air in young female adults. Methods: and analysis: This study is a two-arm, parallel-group, open-label, randomised controlled superiority trial. Forty young female adults will be assigned with a 1:1 allocation ratio to either the Shikuwasa essential oil inhalation group or the odour-free air inhalation group. The primary outcome measure will be subjective tense arousal (subscale of the Japanese version of the University of Wales Institute of Science and Technology Mood Adjective Checklist). Secondary outcomes include objective measures: miosis rate and peripheral skin temperature for evaluating autonomic nervous activity, and cerebral blood flow (assessed using near-infrared spectroscopy) for evaluating central nervous activity. Since these objective outcome measures cannot be performed at the same time, we divide our experiment into three phases and participants will inhale sample vials for 2 min in each experiment. We will also evaluate individual preferences/impressions regarding inhaled samples and any adverse events. Ethics and dissemination: The study protocol has been reviewed and approved by the Research Ethics Committee of the Faculty of Medicine, University of Miyazaki (reference no: I-0074). The findings of this study will be disseminated to academic and professional audiences via publications in peer-reviewed journals and presentations at academic conferences, and to the broader public via public talks and media/press releases. All study findings, whether negative or positive, will be reported. Trial registration: UMIN Clinical Trials Registry (UMIN-CTR), UMIN000053914. Prospectively registered on March 20, 2024.

Mechanism of muscle atrophy in a normal-weight rat model of type 2 diabetes established by using a soft-pellet diet.

Dietary factors such as food texture affect feeding behavior and energy metabolism, potentially causing obesity and type 2 diabetes. We previously found that rats fed soft pellets (SPs) were neither hyperphagic nor overweight but demonstrated glucose intolerance, insulin resistance, and hyperplasia of pancreatic ß-cells. In the present study, we investigated the mechanism of muscle atrophy in rats that had been fed SPs on a 3-h time-restricted feeding schedule for 24 weeks. As expected, the SP rats were normal weight; however, they developed insulin resistance, glucose intolerance, and fat accumulation. In addition, skeletal muscles of SP rats were histologically atrophic and demonstrated disrupted insulin signaling. Furthermore, we learned that the muscle atrophy of the SP rats developed via the IL-6-STAT3-SOCS3 and ubiquitin-proteasome pathways. Our data show that the dietary habit of consuming soft foods can lead to not only glucose intolerance or insulin resistance but also muscle atrophy.

Psychosocial interventions for community-dwelling individuals with schizophrenia: study protocol for a systematic review and meta-analysis.

INTRODUCTION: Despite the recent global mental health movement of the transition from hospital-centred to integrated community-based services, comprehensive evidence of psychosocial interventions focusing on community-dwelling individuals with schizophrenia is still lacking. To overcome this gap in the current knowledge, we will conduct a systematic review and meta-analysis to assess the efficacy of all types of psychosocial interventions for community-dwelling (non-hospitalised) individuals with schizophrenia when compared with non-active control conditions (eg, treatment as usual). METHODS AND ANALYSIS: This study protocol has been developed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines. By March 2022, the following sources will have been searched, without restrictions for language or publication period: Embase, PubMed, PsycINFO, CINAHL, the Cochrane Central Register of Controlled Trials, ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform. We will also try to identify other potentially eligible studies by searching the reference lists of included studies, other relevant systematic reviews and grey literature. All relevant randomised controlled trials from both high-income and low-income to middle-income countries will be allowed. Two independent reviewers will conduct the selection/screening of studies, data extraction and methodological quality assessment of included studies. The primary outcomes are quality of life and psychiatric hospital admission. Standard pairwise meta-analyses with a random-effects model will be conducted. Subgroup and sensitivity analyses will be performed to assess the robustness of the findings. Risk of bias will be assessed with the Revised Cochrane Risk-of-Bias Tool for Randomised Trials. The Grades of Recommendation Assessment, Development and Evaluation approach will be used to assess the quality of evidence. ETHICS AND DISSEMINATION: Ethics approval is not required for this study. The study findings will be disseminated through conference presentations as well as peer-reviewed publications. PROSPERO REGISTRATION NUMBER: CRD42021266187.