Osteoporosis is one of the most common skeletal disorders caused by the imbalance between bone formation and resorption, resulting in quantitative loss of bone tissue. Since stem cell‐derived extracellular vesicles (EVs) are growing attention as novel cell‐free therapeutics that have advantages over parental stem cells, the therapeutic effects of EVs from adipose tissue‐derived stem cells (ASC‐EVs) on osteoporosis pathogenesis were investigated. ASC‐EVs were isolated by a multi‐filtration system based on the tangential flow filtration (TFF) system and characterized using transmission electron microscopy, dynamic light scattering, zeta potential, flow cytometry, cytokine arrays, and enzyme‐linked immunosorbent assay. EVs are rich in growth factors and cytokines related to bone metabolism and mesenchymal stem cell (MSC) migration. In particular, osteoprotegerin (OPG), a natural inhibitor of receptor activator of nuclear factor‐κB ligand (RANKL), was highly enriched in ASC‐EVs. We found that the intravenous administration of ASC‐EVs attenuated bone loss in osteoporosis mice. Also, ASC‐EVs significantly inhibited osteoclast differentiation of macrophages and promoted the migration of bone marrow‐derived MSCs (BM‐MSCs). However, OPG‐depleted ASC‐EVs did not show anti‐osteoclastogenesis effects, demonstrating that OPG is critical for the therapeutic effects of ASC‐EVs. Additionally, small RNA sequencing data were analysed to identify miRNA candidates related to anti‐osteoporosis effects.
miR‐21‐5p
in ASC‐EVs inhibited osteoclast differentiation through
Acvr2a
down‐regulation. Also,
let‐7b‐5p
in ASC‐EVs significantly reduced the expression of genes related to osteoclastogenesis. Finally, ASC‐EVs reached the bone tissue after they were injected intravenously, and they remained longer. OPG,
miR‐21‐5p
, and
let‐7b‐5p
in ASC‐EVs inhibit osteoclast differentiation and reduce gene expression related to bone resorption, suggesting that ASC‐EVs are highly promising as cell‐free therapeutic agents for osteoporosis treatment.
A new Schiff-base colorimetric chemosensor 1 was developed for the detection of Cu, Co and S. Sensor 1 could simply monitor Cu and Co by a color change from colorless to yellow. The binding modes of 1 to Cu and Co were determined to be a 2 : 1 complexation stoichiometry through Job's plot and ESI-mass spectrometry analysis. The detection limits (0.02 μM and 0.63 μM) for Cu and Co were lower than the recommended values (31.5 μM and 1.7 μM) by the World Health Organization (WHO) for Cu and the Environmental Protection Agency (EPA) for Co, respectively. Importantly, 1 could detect and quantify Cu in real water samples. In addition, the Cu-2·1 complex could be used as a highly selective colorimetric sensor for S in the presence of other anions without any interference. Moreover, the sensing mechanisms of Cu and Co by 1 were explained by theoretical calculations.
Stretchable electronic devices should be enabled by the smart design of materials and architectures because their commercialization is limited by the tradeoff between stretchability and electrical performance limits. In this study, thin‐film transistors are fabricated using strategies that combine the unit process of a novel hybrid gate insulator and low‐temperature indium gallium tin oxide (IGTO) channel layer and a stress‐relief substrate structure. Novel hybrid dielectric films are synthesized and their molecular structural configurations are analyzed. These films consist of a polymer [poly(4‐vinylphenol‐co‐methylmethacrylate)], cross‐linkers having different binding structures [1,6‐bis(trimethoxysilyl)hexane (BTMSH), dodecyltrimethoxysilane, and poly(melamine‐co‐formaldehyde)], and an inorganic zirconia component (ZrOx). The hybrid film with BTMSH cross‐linker and 0.2 M ZrOx exhibits excellent insulating properties as well as mechanical stretchability. IGTO transistors fabricated on polyimide‐coated glass substrates are transferred to the rubber substrate to offer stretchability of the transistor pixelated thin‐film transistors. IGTO transistors fabricated on stretchable substrates using these strategies show promising electrical performance and mechanical durability. After 200 stretchability test cycles under uniaxial elongation of approximately 300%, the IGTO transistor still retains a high carrier mobility of 21.7 cm2 V−1 s−1, a low sub‐threshold gate swing of 0.68 V decade−1 and a high ION/OFF ratio of 2.0 × 107.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.