Osaka University

About: Osaka University is a education organization based out in Osaka, Japan. It is known for research contribution in the topics: Laser & Population. The organization has 83778 authors who have published 185669 publications receiving 5158122 citations. The organization is also known as: Ōsaka daigaku.

Fibrosis and adipogenesis originate from a common mesenchymal progenitor in skeletal muscle.

Abstract: Accumulation of adipocytes and collagen type-I-producing cells (fibrosis) is observed in muscular dystrophies. The origin of these cells had been largely unknown, but recently we identified mesenchymal progenitors positive for platelet-derived growth factor receptor alpha (PDGFRα) as the origin of adipocytes in skeletal muscle. However, the origin of muscle fibrosis remains largely unknown. In this study, clonal analyses show that PDGFRα + cells also differentiate into collagen type-I-producing cells. In fact, PDGFRα + cells accumulated in fibrotic areas of the diaphragm in the mdx mouse, a model of Duchenne muscular dystrophy. Furthermore, mRNA of fibrosis markers was expressed exclusively in the PDGFRα + cell fraction in the mdx diaphragm. Importantly, TGF-β isoforms, known as potent profibrotic cytokines, induced expression of markers of fibrosis in PDGFRα + cells but not in myogenic cells. Transplantation studies revealed that fibrogenic PDGFRα + cells mainly derived from pre-existing PDGFRα + cells and that the contribution of PDGFRα − cells and circulating cells was limited. These results indicate that mesenchymal progenitors are the main origin of not only fat accumulation but also fibrosis in skeletal muscle.

Modulating charge separation and charge recombination dynamics in porphyrin-fullerene linked dyads and triads: Marcus-normal versus inverted region.

Abstract: Photoinduced charge separation (CS) and charge recombination (CR) processes have been examined in various porphyrin−fullerene linked systems (i.e., dyads and triads) by means of time-resolved transient absorption spectroscopy and fluorescence lifetime measurements. The investigated compounds comprise a homologous series of rigidly linked, linear donor−acceptor arrays with different donor−acceptor separations and diversified donor strength: freebase porphyrin−C60 dyad (H2P-C60), zincporphyrin−C60 dyad (ZnP-C60), ferrocene−zincporphyrin−C60 triad (Fc-ZnP-C60), ferrocene−freebase porphyrin−C60 triad (Fc-H2P-C60), and zincporphyrin−freebase porphyrin−C60 triad (ZnP-H2P-C60). Most importantly, the lowest lying charge-separated state of all the investigated systems, namely, that of ferrocenium ion (Fc+) and the C60 radical anion (C60•-) pair in the Fc-ZnP-C60 triad, has been generated with the highest quantum yields (close to unity) and reveals a lifetime as long as 16 μs. Determination of CS and CR rate const...

Preorganized hydrogel: self-healing properties of supramolecular hydrogels formed by polymerization of host-guest-monomers that contain cyclodextrins and hydrophobic guest groups

Abstract: Supramolecular hydrogels formed by a host-guest interaction show self-healing properties. The cube-shaped hydrogels with β-cyclodextrin and adamantane guest molecules mend after being broken. The hydrogels sufficiently heal to form a single gel, and the initial strength is restored. Although contact between a freshly cut and uncut surface does not mend the gels, two freshly cut surfaces selectively mend.