The quantity and quality of scientific evidence about the health of working women in occupational health of Japan: A scoping review.

OBJECTIVE: We aim to investigate the quantity and quality of scientific evidence dealing with comprehensive health issues of working women in occupational health. METHODS: This scoping review of original articles that investigated comprehensive health issues of working women aged 19-64 years in Japan was published in PubMed (1967-2022) and Igaku Chuo Zasshi (or Ichu-shi, 1982-2022). Using identical broad search terms, we first identified 17 122 English and 6154 Japanese articles. We excluded those with clinically relevant topics, or ethnicity other than Japanese and included 853 English and 855 Japanese articles for review and classified them into nine research areas considered to be critical factors for women in the workforce and five study design groups to investigate the quality of the evidence accumulated. RESULTS: Among 853 English-language articles in PubMed, "Mental health" was the most frequent area studied, followed by "Work-related disease" and "Lifestyle-related disease." Among 855 Japanese-language articles from Ichu-shi, "Mental health" was the most frequently studied area followed by "Work and balance," and "Work-related disease." "Infertility, pregnancy, and childbirth" and "Menstruation, menopause, and genital disease" were well studied in Ichu-shi but scarcely published in PubMed. "Harassment and discrimination" were sparsely reported in both databases. As for research designs, many articles in both PubMed and Ichu-shi employed descriptive or cross-sectional study designs. However, a few studies employed cohort/longitudinal or interventional studies. CONCLUSION: The results underscored the need for higher-quality study designs with more scientific evidence on working women's health in the field of occupational health.

Crystal structure of mevalonate 3,5-bisphosphate decarboxylase reveals insight into the evolution of decarboxylases in the mevalonate metabolic pathways.

Mevalonate 3,5-bisphosphate decarboxylase is involved in the recently discovered Thermoplasma-type mevalonate pathway. The enzyme catalyzes the elimination of the 3-phosphate group from mevalonate 3,5-bisphosphate as well as concomitant decarboxylation of the substrate. This entire reaction of the enzyme resembles the latter half-reactions of its homologs, diphosphomevalonate decarboxylase and phosphomevalonate decarboxylase, which also catalyze ATP-dependent phosphorylation of the 3-hydroxyl group of their substrates. However, the crystal structure of mevalonate 3,5-bisphosphate decarboxylase and the structural reasons of the difference between reactions catalyzed by the enzyme and its homologs are unknown. In this study, we determined the X-ray crystal structure of mevalonate 3,5-bisphosphate decarboxylase from Picrophilus torridus, a thermoacidophilic archaeon of the order Thermoplasmatales. Structural and mutational analysis demonstrated the importance of a conserved aspartate residue for enzyme activity. In addition, although crystallization was performed in the absence of substrate or ligands, residual electron density having the shape of a fatty acid was observed at a position overlapping the ATP-binding site of the homologous enzyme, diphosphomevalonate decarboxylase. This finding is in agreement with the expected evolutionary route from phosphomevalonate decarboxylase (ATP-dependent) to mevalonate 3,5-bisphosphate decarboxylase (ATP-independent) through the loss of kinase activity. We found that the binding of geranylgeranyl diphosphate, an intermediate of the archeal isoprenoid biosynthesis pathway, evoked significant activation of mevalonate 3,5-bisphosphate decarboxylase, and several mutations at the putative geranylgeranyl diphosphate-binding site impaired this activation, suggesting the physiological importance of ligand binding as well as a possible novel regulatory system employed by the Thermoplasma-type mevalonate pathway.