Eukaryotic cells, when exposed to stress, stop protein translation and form cytoplasmic granules called stress granules (SGs) containing mRNAs and mRNA-binding proteins such as Ras-GAP SH3 domain-binding protein (G3BP) 1 and 2. Cells are thought to survive stress by utilizing SGs as the platform of RNA triage. Accordingly, in cancer cells, SGs are proposed to cause resistance against anti-cancer drugs. We initiated this study to identify novel compounds that induce SGs. We exposed human keratinocyte HaCaT cells to various chemical compounds and immunostained them with anti-G3BP antibody. We found that the cells exposed to topoisomerase inhibitors, teniposide and topotecan, form G3BP-containing aggregates (GCAs). GCAs look like SGs, but are formed more slowly and are not dissociated after stress removal. GCA formation is not associated with eIF2α phosphorylation, while in most cases SG formation depends on it. More importantly, GCAs do not contain representative components of SGs or mRNAs. In sum, we have unexpectedly found a novel cytoplasmic structure ｃontaining G3BP that is distinct from SG.

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This study examined nurses’ self-evaluation of their nursing work, determined whether there were variations in these self-evaluations, and explored how work environment factors influence them. Data were collected using a large-scale survey (31,657 objects). We extracted the essential principal components from the data on self-evaluation of nursing work and identified differences in principal component scores among workplace classifications and age groups. We also evaluated the relationships between scores for selfevaluation of nursing work and work environment factors using multiple regression models. Work environment factors significantly affected nurses’ intention to separate from employment (adjusted R² = 0.230) but exerted weaker effects on adequate nursing provision (adjusted R² = 0.028) and sense of fulfillment in nursing work (adjusted R² = 0.042). Both individual work environments (external factors) and nurses’ personal attributes (internal factors) should be considered major targets in implementing countermeasures for nurse turnover. Among the external factors, reduction of workload and organizational eradication of power harassment specifically demonstrated relationships with a sense of fulfillment in nursing work, and may act as additional countermeasures for nurse turnover.

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