Best practice transfer by public health nurses in Japan: actual conditions and related factors.

BACKGROUND: The workload of public health nurses (PHNs) working for local governments has been increasing as health issues become more diverse and complicated. Even amidst the ongoing administrative and fiscal reforms, there is an urgent need to ensure how effectively and efficiently public health nurses can practice in health service development. The objective of this research was to clarify the actual conditions of best practice transfer (BPT) and its related factors. METHODS: An anonymous postal and self-administered questionnaire survey was conducted among PHNs working at 334 sites, including the local government offices and health centers across Japan, and analysed mainly through logistic regression analysis. RESULTS: One hundred eighty-five of the 334 institutions (55.4%) agreed to participate, and of the 966 questionnaire forms distributed, 709 forms (73.4%) were collected, of which 702 responses (72.7%) were valid. Although less than half (43.2%) have experience in BPT in health service development, more than 80% are willing to perform going forward. Significant factors for both the group with experience in BPT and the group with willingness to perform include an organizational culture that promotes BPT, as well as multiple elements of the workplace environment and facilitating factors related to knowledge and learning. The experienced group recognised the needs for criteria to evaluate the adaptability of best practice, while the willing group, to evaluate the quality of practice. CONCLUSIONS: Through a nationwide survey, this research elucidated for the first time the actual conditions of BPT by PHNs in Japan and related factors. The results indicated the importance of developing a system to promote BPT at the workplace level, also highlighted the importance for practitioners and experts, including researchers, to work together to develop practical guidelines to ensure evidence-based practices. Urgent actions are needed for the national and local governments to develop a system to promote BPT from diverse perspectives, building on the findings of this research.

Robust and Objective Evaluation of Superficial Punctate Keratopathy in a Murine Dry Eye Model.

Purpose: To establish a robust and objective method to evaluate (SPK) superficial punctate keratopathy in a murine dry eye model by developing a reliable photographic system. Design: Experimental study. Subjects: A murine dry eye model was generated by exorbital lacrimal gland excision. Sham-operated mice were used as healthy controls. For the sham operation, an incision was made without touching the gland. Methods: A photographic system was constructed, consisting of an LED lamp and a digital camera fitted with a zoom lens and sharp cut filter. SPK was detected by applying fluorescein solution. To validate the system, SPK was compared between dry eye mice and healthy control mice, and diquafosol (DIQUAS ophthalmic solution 3%; Santen Pharmaceutical Co., Ltd.) or cyclosporine (PAPILOCK Mini ophthalmic solution 0.1%; Santen Pharmaceutical Co., Ltd.) was used to dry eye mice. Main Outcome Measures: SPK was evaluated using the parameters of fluorescence score and fluorescein-stained area. Results: The photographs clearly indicated SPK in dry eye mice. A fluorescence score of 0 to 9 could be easily assessed, and the fluorescein-stained area was quantifiable. The fluorescein-stained area correlated with fluorescence score (correlation coefficient: 0.98), with good interobserver reliability (intraclass correlation coefficient: 0.999). The fluorescein-stained area increased significantly in dry eye mice compared with that of healthy controls (P < 0.0001). Both types of therapeutic eye drops decreased the fluorescein-stained area relative to saline-treated mice (P < 0.05 in diquafosol vs. saline; P < 0.01 in cyclosporine vs. saline). Conclusions: This newly developed system is a robust alternative for quantitative evaluation of SPK in a murine dry eye model. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Testing a frailty prevention program for older men during COVID-19: A 2-year mixed-methods pilot study.

BACKGROUND: Frailty is a syndrome related to declining functioning attributed to aging. As a reversible, often improved condition, preventive measures for frailty can be effective. OBJECTIVE: This study aimed to evaluate a frailty prevention program for older men comprising face-to-face meetings and an original social mobile application. We also examined the effect of COVID-19-associated social isolation on the implementation of this program. METHODS: We conducted a mixed-methods pilot study featuring a single group before and after comparison of 11 man participants, ≥65 years, living in Japanese cities with a spouse or relatives. Program outcome measures included frailty, loneliness, grip strength, step count and mental health status. Process evaluation considered the experience of participants through a semi-structured interview. RESULTS: The intervention period included an interval of self-isolation owing to the spread of COVID-19. Among the outcomes, grip strength decreased after intervention. No significant negative changes were observed in other items. Themes emerging from participant experiences with the program included 'Cooperation with researchers and contributing to research', 'Greater awareness of health', 'Interest in and experience of "newness"', 'Hesitation over active engagement', 'Casual ties with members' and 'Relationships that do not breach personal boundaries'. CONCLUSIONS: Although the COVID-19 pandemic overlapped with the intervention, participants maintained their mental health. The program was a novel, stimulating experience for older men and demonstrated the usefulness of information and communication technology in supporting their social activities. IMPLICATIONS FOR PRACTICE: As a community health nursing initiative for older people, we propose activities that combine group and online support. Frailty prevention programs for older men must contain content that stimulates their interests, such as 'health' and 'newness'.

[Developing scales to evaluate community practices among municipal public health nurses: content, perceptions of public health nurses, and organizational environment].

Objectives　This study aimed to develop scales for evaluating the level of implementation of community practices and explore the perception of public health nurses in municipalities regarding their community practices.Methods　Draft scales were developed based on a literature review and interviews with municipal public health nurses. Subsequently, a questionnaire survey was conducted with municipal public health nurses across Japan in response to these draft scales. Respondents were recruited based on the municipality population size. Questionnaires were distributed to 2,074 individuals from 52 municipalities ensuring representation from diverse municipalities. Exploratory factor analysis was performed to determine the number of factors, while confirmatory factor analysis was performed to determine the factor structure. The reliability of the scales was assessed by calculating Cronbach's alpha coefficients, and their validity was tested by examining correlations with existing scales, namely the Moral Competence Scale for Public Health Nurses and the Professional Identity Scale for Public Health Nurses, and years of experience as a public health nurse.Results　A total of 721 (34.8%) valid respondents were included in the analysis. Three scales, methods of community practices (three factors, nine items), perceptions of public health nurses toward community residents through community practices (three factors, 10 items), and organizational environment supporting community practices (two factors, 11 items) were developed as indicators of the implementation of public health nurses' community practices. Cronbach's alpha coefficients for the three scales were 0.896, 0.913, and 0.868, respectively. As hypothesized, each subfactor exhibited a positive correlation with the existing scales. However, certain subfactors did not demonstrate any correlation with years of experience.Conclusion　The three scales developed in this study were individually examined for reliability and validity. These scales can be used independently or in combination, allowing public health nurses to select the most suitable scale(s) based on their objective.　A notable contribution of this study is the establishment of concrete indicators for evaluating community practices, addressing the previously vague nature of this evaluation. By incorporating the scale items into daily health practices, we anticipate that these indicators can be employed to evaluate community practices at the organizational and individual levels.

Deficiency of leukotriene B4 receptor type 1 ameliorates ovalbumin-induced allergic enteritis in mice.

Leukotriene B4 receptor type 1 (BLT1), a high-affinity receptor for leukotriene B4 (LTB4), plays an important role in inflammatory responses, including allergic airway inflammation. In this study, we examined the effect of genetic BLT1 deletion (BLT1KO) on ovalbumin (OVA)-induced allergic enteritis in mice to determine the pathogenic role of LTB4/BLT1 in allergic enteritis, a gastrointestinal form of food allergy. Repeated oral OVA challenges after sensitization with OVA and aluminium potassium sulphate induced allergic enteritis, characterized by systemic allergic symptoms (scratching, immobility and swelling), diarrhoea, colonic oedema and colonic goblet cell hyperplasia, accompanied by increased colonic peroxidase activity, colonic inflammatory cytokine expression and increased serum OVA-specific IgE levels. The severity of enteritis was significantly attenuated in BLT1KO mice compared with wild-type (WT) mice, without an increase in serum OVA-specific IgE levels. The accumulation of neutrophils, eosinophils, M2-macrophages, dendritic cells, CD4+ T cells and mast cells was observed in the colonic mucosa of allergic enteritis, and such accumulation was significantly lower in BLT1KO mice than in WT mice. BLT1 expression was upregulated and colocalized mostly in neutrophils and partly in eosinophils and dendritic cells in the colonic mucosa of allergic enteritis. These findings indicate that BLT1 deficiency ameliorates OVA-induced allergic enteritis in mice and that LTB4/BLT1 contributes to neutrophil and eosinophil accumulation in the allergic colonic mucosa. Therefore, BLT1 is a promising drug target for treating food allergies.

Effects of a 'social activity program that encourages interaction' on rural older people's psychosocial health: Mixed-methods research.

BACKGROUND: We developed a program that encourages interaction among older people living at home by combining face-to-face and online activities and examined its effects on older adults' psychosocial health. METHODS: In this mixed-methods study, we recruited 11 women and 6 men (Mage = 79.5 ± 6.4 years), who lived in a rural community and participated in a senior citizen club. The intervention was conducted for 13 months, comprising monthly face-to-face group and social media activities. For the program process evaluation, we collected focus-group interview data on participants' perceptions of their personal lives, club membership, and community post-intervention. For the outcome evaluation, we collected six outcome measures pre- and post-intervention: loneliness, subjective health, subjective well-being, self-esteem, social support and social activity satisfaction. Finally, through the integration of the process-outcome evaluation, we inferred what effects the program had on participants' psychosocial health. RESULTS: In the process evaluation, we identified four themes: 'Stimulation brought about by relationships with peers,' 'Realization as to where they feel they belong,' 'Rethinking of oneself in the community,' and 'Awareness of attachment to and coexistence with the community.' In the outcome evaluation, the outcome measures were maintained without significant decline post-intervention. CONCLUSION: Through the integration of the process-outcome evaluation, we deduced three effects of the program on psychosocial health: (1) fulfilment of subjective health, (2) maintenance and assurance of moderate distance connectedness and (3) orientation toward aging in place. IMPLICATIONS FOR PRACTICE: This study offers a promising opportunity for further development and research into community-based preventive nursing care intervention strategies to maintain the psychosocial health of homebound older people in communities with social activity groups.

The leukotriene B4 /BLT1-dependent neutrophil accumulation exacerbates immune complex-mediated glomerulonephritis.

Crescent formation is the most important pathological finding that defines the prognosis of nephritis. Although neutrophils are known to play an important role in the progression of crescentic glomerulonephritis, such as anti-neutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis, the key chemoattractant for neutrophils in ANCA-associated glomerulonephritis has not been identified. Here, we demonstrate that a lipid chemoattractant, leukotriene B4 (LTB4 ), and its receptor BLT1 are primarily involved in disease pathogenesis in a mouse model of immune complex-mediated crescentic glomerulonephritis. Circulating neutrophils accumulated into glomeruli within 1 h after disease onset, which was accompanied by LTB4 accumulation in the kidney cortex, leading to kidney injury. LTB4 was produced by cross-linking of Fc gamma receptors on neutrophils. Mice deficient in BLT1 or LTB4 biosynthesis exhibited suppressed initial neutrophil infiltration and subsequent thrombotic glomerulonephritis and renal fibrosis. Depletion of neutrophils before, but not after, disease onset prevented proteinuria and kidney injury, indicating the essential role of neutrophils in the early phase of glomerulonephritis. Administration of a BLT1 antagonist before and after disease onset almost completely suppressed induction of glomerulonephritis. Finally, we found that the glomeruli from patients with ANCA-associated glomerulonephritis contained more BLT1-positive cells than glomeruli from patients with other etiologies. Taken together, the LTB4 -BLT1 axis is the key driver of neutrophilic glomerular inflammation, and will be a novel therapeutic target for the crescentic glomerulonephritis.

Value of social activities and prerequisites for continued participation of rural older adults: A qualitative study.

AIMS: To explore the value of social activities and the prerequisites for continuous participation among rural older adults based on their experiences. DESIGN: Qualitative, descriptive design. METHODS: Individual semi-structured interviews were conducted with 14 older adults from voluntary community salons in a rural area in Japan. Participants were selected through purposeful sampling. Data were analyzed using qualitative content analysis. The consolidated criteria for reporting qualitative research (COREQ) checklist were used. RESULTS: Four values of social activities were identified: "Mutual benefit connectedness," "Preventing and coping with aging," "Making life brilliant 'now'," and "Building a safety net." Three prerequisites for activities were identified: "Do not overreach," "Do not infringe on personal territory," and "Do not go against community norms." Social activities provide rural older adults with reciprocity ties, coping with aging, enhanced daily lives, and a social safety net. Continued participation in rural social activities requires adherence to cultural norms and moderation of relationship distances. Community and public health nurses are expected to promote social activities that incorporate these values and adhere to these prerequisites.

Implementation Degree Assessment Sheet for Health Program in Japan by Customizing CFIR: Development and Validation.

PURPOSE: More than 70% of public health nurses in Japan belong to government agencies, and there is a need for further evidence-based capacity development for program implementation. The purpose of this research was to develop an Implementation Degree Assessment Sheet (IDAS) by customizing the Consolidated Framework for Implementation Research (CFIR) to health programs in Japan. METHODS: The draft IDAS (five domains, 31 constructs) created by customizing the CFIR was refined by the researchers and modified through pre-testing. The survey covered full-time public health nurses (PHNs) affiliated to all prefectures and the cities with health centers of Japan. The survey was conducted as an anonymous, self-administered questionnaire survey by mail. RESULTS: One hundred eighty-five of the 334 institutions (55.4%) agreed to participate in our survey. Of the 966 questionnaire forms distributed, 709 forms (73.4%) were collected, of which 702 responses (72.7%) were valid. No item required consideration of deletion based on the results of item analysis, and our confirmatory factor analysis on model fitness between the five IDAS domains and CFIR showed sufficient fit indices after modification. With regard to reliability, Cronbach's coefficient alpha, a measure of internal consistency, stayed above 0.8 overall. Our verification of stability with the split-half (odd/even) method resulted in a Spearman-Brown reliability coefficient of 0.95. The correlation coefficient between the IDAS scores and the research utilization competency score, used as an external criterion, was 0.51 (p<0.001), supporting the coexistence validity of the criterion-related validity of the IDAS. The significant differences were observed between known-groups, supporting the known-group validity of the IDAS. CONCLUSION: This study developed the IDAS and confirmed constant reliability and validity. Hereafter, it is necessary to promote the required capacity development based on the actual degree of implementation in order to use the IDAS for the competency development of public health nurses and related professions to deliver health programs.

Novice public health nurses' home-visit skills in Japan: A one-year longitudinal study.

OBJECTIVE: This study aimed to clarify the status of novice public health nurses' home-visit skills during their first year of practice. DESIGN AND SAMPLE: A one-year longitudinal observational study was conducted with 80 novice public health nurses. The participants were recruited from the four Japanese prefectures and their affiliated municipalities selected by using stratified sampling. MEASUREMENTS: Self-administered questionnaires were distributed three times between April 2016 and March 2017, asking about home-visit experiences, understandings of the significance of home-visit, and the levels of home-visit skills. Data were analyzed with paired t-tests and Wilcoxon signed-rank tests. RESULTS: All of twenty skills' self-ratings significantly increased between the fourth and eighth months; five skills continually increased between the eighth and twelfth months. Both of Physical Assessment and Relationship Development Skills improved to the "Can do, almost by myself" level at the twelfth month; other skills remained at the "Can do, with a little advice" level. CONCLUSION: Although novice public health nurses improved to conducted home-visits independently, they didn't perceive themselves as being able to do so in their first year. Therefore, through preparing guideline, organizations should provide intentional support to assist their skill acquisition during their first, and even in their second year.

[Gaining consensus on key terms in community health activities: A national survey using the Delphi method].

Objectives　The purpose of this study was to define the terminology used in community health activities by systematically establishing agreement among public health nurses and related professionals, to aid them in effectively cooperating with other professionals.Methods　We extracted the major terms described in "Guidelines for Public Health Nurses' Activities in the Region," which was issued by the Director of Health Bureau, Ministry of Health, Labor and Welfare; and conducted 2 iterations on the proposed definition of the terms using the Delphi method. The survey targeted 800 stakeholders from the following 4 professions: public health nurses in managerial positions in local governments, clerical staff in local governments, public health nursing professors at educational institutions, and social welfare council staff. Respondents indicated their degree of agreement with the definition of the terms using a 4-point Likert scale. We tallied the answers indicating "I agree" or "Mostly agree." A 70% term agreement was considered "conformed." A free text box for each proposed definition was also available so that respondents could share their opinions and offer alternatives.Results　The first survey received 231 responses. The conformity of their definitions ranged from 83.9%-96.9% (mean=91.5%). Although all definitions exceeded the consensus level, we examined their adequacy with reference to the definitions and opinions from the free text. Various opinions were obtained from those engaged in each occupation. The second round included 117 consenting stakeholders from the first survey, yielding 90 responses. Their degree of conformity ranged from 86.7%-98.9% (mean=94.6%). Therefore, we determined the definitions had reached a robust agreement. We revised the definitions of some terms with reference to the opinions from the free texts and finalized the definitions. Finally, we defined 23 terms-such as region, community diagnosis, and policy.Conclusion　All terms had a conformity of more than 85%, thus bringing into alignment those community health terms that had varying interpretations among related occupations earlier. By including the opinions of those from the related occupations who collaborate with public health nurses, the definitions of these terms could be established and shared. These definitions can be used in public health nursing practice, education, service, and research-among those in involved these related occupations.

Up-regulation of cytosolic prostaglandin E synthase in fetal-membrane and amniotic prostaglandin E2 accumulation in labor.

Prostaglandin E2 (PGE2) is known to have important roles in labor, but the detailed mechanism underlying the spontaneous human labor remains unknown. Here, we examined the involvement of prostaglandin biosynthetic enzymes and transporter in the accumulation of PGE2 in amniotic fluid in human labor. PGE2 and its metabolites were abundant in amniotic fluid in deliveries at term in labor (TLB), but not at term not in labor (TNL). In fetal-membrane Transwell assays, levels of PGE2 production in both maternal and fetal compartments were significantly higher in the TLB group than the TNL group. In fetal-membrane, the mRNA level of PTGES3, which encodes cytosolic prostaglandin E synthase (cPGES), was significantly higher in TLB than in TNL, but the mRNA levels of the other PGE2-synthase genes were not affected by labor. Moreover, the mRNA level of PTGS2, which encodes cyclooxygenase-2 (COX-2) in the amnion was significantly higher in TLB than in TNL. Western blot analyses revealed that the levels of COX-1 and COX-2 were comparable between the two groups, however, the level of cPGES was relatively higher in TLB than in TNL. COXs, cPGES, and prostaglandin transporter (SLCO2A1) proteins were all expressed in both chorionic trophoblasts and amniotic epithelium. These findings suggest that COXs, cPGES and SLCO2A1 contribute to PGE2 production from fetal-membrane in labor.

The c-terminal region of BLT2 restricts its localization to the lateral membrane in a LIN7C-dependent manner.

Leukotriene B4 receptor type 2 (BLT2) is a G protein-coupled receptor (GPCR) mainly expressed in epithelial cells, where it enhances barrier function. A unique characteristic of BLT2 is its restricted localization to the lateral membrane. However, the molecular mechanism underlying the localization of BLT2 to the lateral membrane and the physiological roles of laterally localized BLT2 are unknown. BLT1 is the most homologous GPCR to BLT2 and localizes to both the apical and lateral membranes. In this study, we generated chimeric receptors of BLT2 and BLT1 as well as deletion mutants of BLT2 to determine the region(s) of BLT2 responsible for its localization. Chimeric receptors containing the C-terminal domain of BLT2 localized only to the lateral membrane, and the C-terminal deletion mutant of BLT2 accumulated at the Golgi apparatus. Furthermore, the middle and C-terminal regions of BLT2 were important for maintaining epithelial barrier function. Proteomics analysis using the chimeric BLT-ascorbate peroxidase 2 biotinylation method showed that some proteins involved in intracellular protein transport, cell-cell junctions, and actin filament binding were located very close to the C-terminal domain of BLT2. Knockdown of lin-7 homolog C (LIN7C), a membrane trafficking protein, led to accumulation of BLT2 in the Golgi apparatus, resulting in diminished epithelial barrier function. These results suggest that the C-terminal region of BLT2 plays an important role in the transport of BLT2 from the Golgi apparatus to the plasma membrane in a LIN7C-dependent manner.

Expression of leukotriene B4 receptor 1 defines functionally distinct DCs that control allergic skin inflammation.

Leukotriene B4 (LTB4) receptor 1 (BLT1) is a chemotactic G protein-coupled receptor expressed by leukocytes, such as granulocytes, macrophages, and activated T cells. Although there is growing evidence that BLT1 plays crucial roles in immune responses, its role in dendritic cells remains largely unknown. Here, we identified novel DC subsets defined by the expression of BLT1, namely, BLT1hi and BLT1lo DCs. We also found that BLT1hi and BLT1lo DCs differentially migrated toward LTB4 and CCL21, a lymph node-homing chemoattractant, respectively. By generating LTB4-producing enzyme LTA4H knockout mice and CD11c promoter-driven Cre recombinase-expressing BLT1 conditional knockout (BLT1 cKO) mice, we showed that the migration of BLT1hi DCs exacerbated allergic contact dermatitis. Comprehensive transcriptome analysis revealed that BLT1hi DCs preferentially induced Th1 differentiation by upregulating IL-12p35 expression, whereas BLT1lo DCs accelerated T cell proliferation by producing IL-2. Collectively, the data reveal an unexpected role for BLT1 as a novel DC subset marker and provide novel insights into the role of the LTB4-BLT1 axis in the spatiotemporal regulation of distinct DC subsets.

The values and meanings of social activities for older urban men after retirement.

Previous studies have indicated that older men often experience disconnection from the community after retirement. Social activities have been shown to be effective in preventing social isolation among older urban men. Nevertheless, it has been reported that they often do not participate in community social activities and tend to be reluctant to do so. We explored the values and meanings of social activities for retired older men living in an urban area of Japan to understand support using social activities that are more suitable for them. Semi-structured interviews were conducted with 15 older men (aged 68-80 years; M = 74.6 ± 3.79 years) about their interactions with family and non-family members, and their participation in various community social activities. The grounded theory approach was used for the analysis. As a result, the following five categories were derived as the values that participants place on the social activities that they engage in: "health as a resource and reward for social activities," "feeling I am still useful," "feeling that something is my responsibility," "feeling of time well spent," and "finding interest through interactions." In addition, the following three categories were extracted as meanings of social activities: "fulfilling social life," "maintaining stable family relationships," and "maintaining safety and peace in the community." When considering the social activities that older urban retired men are interested in and likely to participate in, these five values can be considered indicators. In contrast, to maintain stable family relationships and safety and peace in the community, participants sometimes used strategies to stop or abandon social activities. Therefore, in situations where a peaceful life within a family or neighborhood is threatened, it may be useful to help set aside sufficient time and allow for psychological leeway in advance to incorporate social activities into their lives.

Perception of COVID-19 Restrictions on Daily Life among Japanese Older Adults: A Qualitative Focus Group Study.

The coronavirus disease 2019 (COVID-19) pandemic has exposed older adults to health and social risks. This study examined the perceptions of community-dwelling older adults regarding how COVID-19 restricted their daily lives. Six focus-group interviews were conducted with 24 participants (mean age, 78.2 ± 5.5 years) living in urban and rural areas in Japan. Then, a qualitative inductive content analysis was performed. Six themes were generated: "fear of infection and public, watchful eyes," "consistency in daily personal life," "pain from reducing my social life," "readiness to endure a restricted life," "awareness of positive changes in myself," and "concern for a languishing society." There was no change that would make their lives untenable, and they continued their daily personal lives at a minimum level. However, their social lives were reduced, which over the long term can lead to a lost sense of purpose in life. This was reported as an adverse factor in the development of other diseases and functional decline in previous studies. While there is no doubt that infection prevention is important, supporting older adults in engaging in activities that provide a sense of purpose in life could contribute to their present and future overall health including mental health.

Development of a social activities scale for community-dwelling older people requiring support.

Aim: This study aims to develop the Social Activities Scale for Community-Dwelling Older People Requiring Support (SASOS). Design: This study is a cross-sectional investigation. Methods: The participants were healthy older people (HOP; N = 140) and those requiring support (OPRS; N = 250). An anonymous questionnaire included items on SASOS, subjective health and ikigai (Japanese well-being concept). Criterion-related validity was examined using the Social Activity Index for Elderly People (SAI-E). Results: Seventy-five HOP and 157 OPRS provided effective responses. The scale (α = 0.805) had three subscales: "interactions with friends and neighbors (F1)," "close relationships with family (F2)" and "interactions with others through activity programs (F3)." SASOS and SAI-E scores were correlated (r = .558, p < .01), indicating criterion-related validity. In known-groups validity analysis, F1 were significantly higher among HOP and F3 were significantly higher among OPRS. Total scores correlated with perceived health (r = .240, p < .01) and ikigai (r = .419, p < .01).

Leukotriene A4 hydrolase deficiency protects mice from diet-induced obesity by increasing energy expenditure through neuroendocrine axis.

Obesity is a health problem worldwide, and brown adipose tissue (BAT) is important for energy expenditure. Here, we explored the role of leukotriene A4 hydrolase (LTA4 H), a key enzyme in the synthesis of the lipid mediator leukotriene B4 (LTB4 ), in diet-induced obesity. LTA4 H-deficient (LTA4 H-KO) mice fed a high-fat diet (HFD) showed a lean phenotype, and bone-marrow transplantation studies revealed that LTA4 H-deficiency in non-hematopoietic cells was responsible for this lean phenotype. LTA4 H-KO mice exhibited greater energy expenditure, but similar food intake and fecal energy loss. LTA4 H-KO BAT showed higher expression of thermogenesis-related genes. In addition, the plasma thyroid-stimulating hormone and thyroid hormone concentrations, as well as HFD-induced catecholamine secretion, were higher in LTA4 H-KO mice. In contrast, LTB4 receptor (BLT1)-deficient mice did not show a lean phenotype, implying that the phenotype of LTA4 H-KO mice is independent of the LTB4 /BLT1 axis. These results indicate that LTA4 H mediates the diet-induced obesity by reducing catecholamine and thyroid hormone secretion.