Biogenic Copper Selenide Nanoparticles for Near-Infrared Photothermal Therapy Application.

Near-infrared (NIR) photothermal therapy (PTT) is attractive for cancer treatment but is currently restricted by limited availability and insufficient NIR-II photoactivity of photothermal agents, for which artificial nanomaterials are usually used. Here, we report the first use of biogenic nanomaterials for PTT application. A fine-controlled extracellular biosynthesis of copper selenide nanoparticles (bio-Cu2-xSe) by Shewanella oneidensis MR-1 was realized. The resulting bio-Cu2-xSe, with fine sizes (∼35.5 nm) and high product purity, exhibited 76.9% photothermal conversion efficiency under 1064 nm laser irradiation, outperforming almost all the existing counterparts. The protein capping also imparted good biocompatibility to bio-Cu2-xSe to favor a safe PTT application. The in vivo PTT with injected bio-Cu2-xSe in mice (without extraction nor further modification) showed 87% tumor ablation without impairing the normal organisms. Our work not only opens a green route to synthesize the NIR-II photothermal nanomaterial but may also lay a basis for the development of bacteria-nanomaterial hybrid therapy technologies.

Association between bile acid metabolism and bone mineral density in postmenopausal women

OBJECTIVES: Previous studies have not shown any correlation between bile acid metabolism and bone mineral density (BMD) in women with postmenopausal osteoporosis. Thus, the current study evaluated the association between bile acid levels as well as BMD and bone turnover marker levels in this group of women. METHODS: This single-center cross-sectional study included 150 postmenopausal Chinese women. According to BMD, the participants were divided into three groups: osteoporosis group, osteopenia group, and healthy control group. Serum bile acid, fibroblast growth factor 19 (FGF19), and bone turnover biomarker levels were assessed. Moreover, the concentrations of parathyroid hormone, 25-hydroxy vitamin D [25(OH)D], procollagen type I N-peptide (P1NP), and beta-CrossLaps of type I collagen containing cross-linked C-terminal telopeptide (β-CTX) were evaluated. The BMD of the lumbar spine and proximal femur were examined via dual-energy X-ray absorptiometry. RESULTS: The serum total bile acid levels in the osteoporosis and osteopenia groups (5.28±1.56 and 5.31±1.56 umol/L, respectively) were significantly lower than that in the healthy control group (6.33±2.04 umol/L; p=0.002 and 0.018, respectively). Serum bile acid level was positively associated with the BMD of the lumbar spine, femoral neck, and total hip. However, it negatively correlated with β-CTX concentration. Moreover, no correlation was observed between bile acid and P1NP levels, and the levels of the other biomarkers that were measured did not differ between the groups. CONCLUSION: Serum bile acid was positively correlated with BMD and negatively correlated with bone turnover biomarkers reflecting bone absorption in postmenopausal women. Thus, bile acid may play an important role in bone metabolism.