Osaka University

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

Adiponectin-mediated modulation of hypertrophic signals in the heart.

Abstract: Patients with diabetes and other obesity-linked conditions have increased susceptibility to cardiovascular disorders1. The adipocytokine adiponectin is decreased in patients with obesity-linked diseases2. Here, we found that pressure overload in adiponectin-deficient mice resulted in enhanced concentric cardiac hypertrophy and increased mortality that was associated with increased extracellular signal-regulated kinase (ERK) and diminished AMP-activated protein kinase (AMPK) signaling in the myocardium. Adenovirus-mediated supplemention of adiponectin attenuated cardiac hypertrophy in response to pressure overload in adiponectin-deficient, wild-type and diabetic db/db mice. In cultures of cardiac myocytes, adiponectin activated AMPK and inhibited agonist-stimulated hypertrophy and ERK activation. Transduction with a dominant-negative form of AMPK reversed these effects, suggesting that adiponectin inhibits hypertrophic signaling in the myocardium through activation of AMPK signaling. Adiponectin may have utility for the treatment of hypertrophic cardiomyopathy associated with diabetes and other obesity-related diseases.

The MAXI Mission on the ISS: Science and Instruments for Monitoring All-Sky X-Ray Images

Abstract: The Monitor of All-sky X-ray Image (MAXI) mission is the first astronomical payload to be installed on the Japanese Experiment Module — Exposed Facility (JEM-EF or Kibo-EF) on the International Space Station. It has two types of X-ray slit cameras with wide FOVs and two kinds of X-ray detectors consisting of gas proportional counters covering the energy range of 2 to 30 keV and X-ray CCDs covering the energy range of 0.5 to 12 keV. MAXI will be more powerful than any previous X-ray All Sky Monitor payloads, being able to monitor hundreds of Active Galactic Nuclei. A realistic simulation under optimal observation conditions suggests that MAXI will provide all-sky images of X-ray sources of � 20 mCrab (� 7 � 10 � 10 erg cm � 2 s � 1 in the energy band of 2–30 keV) from observations during one ISS orbit (90 min), � 4.5 mCrab for one day, and � 2 mCrab for one week. The final detectability of MAXI could be � 0.2 mCrab for two years, which is comparable to the source confusion limit of the MAXI field of view (FOV). The MAXI objectives are: (1) to alert the community to X-ray novae and transient X-ray sources, (2) to monitor long-term variabilities of X-ray sources, (3) to stimulate multi-wavelength observations of variable objects, (4) to create unbiased X-ray source cataloges, and (5) to observe diffuse cosmic X-ray emissions, especially with better energy resolution for soft X-rays down to 0.5 keV.

Foxp3+ natural regulatory T cells preferentially form aggregates on dendritic cells in vitro and actively inhibit their maturation.

Abstract: Naturally occurring CD4(+)CD25(+) regulatory T cells (Treg) suppress in vitro the proliferation of other T cells in a cell-contact-dependent manner. Dendritic cells (DCs) appear to be a target of Treg-mediated immune suppression. We show here that, in coculture of dye-labeled Treg cells and CD4(+)CD25(-) naive T cells in the presence of T cell receptor stimulation, Treg cells, which are more mobile than naive T cells in vitro, out-compete the latter in aggregating around DCs. Deficiency or blockade of leukocyte function-associated antigen-1 (LFA-1) (CD11a/CD18) abrogates Treg aggregation, whereas that of cytotoxic T lymphocyte-associated antigen 4 (CTLA-4) (CD152) does not. After forming aggregates, Treg cells specifically down-regulate the expression of CD80/86, but not CD40 or class II MHC, on DCs in both a CTLA-4- and LFA-1-dependent manner. Notably, Treg exerts this CD80/86-down-modulating effect even in the presence of strong DC-maturating stimuli, such as GM-CSF, TNF-alpha, IFN-gamma, type I IFN, and lipopolysaccharide. Taken together, as a possible mechanism of in vitro Treg-mediated cell contact-dependent suppression, we propose that antigen-activated Treg cells exert suppression by two distinct steps: initial LFA-1-dependent formation of Treg aggregates on immature DCs and subsequent LFA-1- and CTLA-4-dependent active down-modulation of CD80/86 expression on DCs. Both steps prevent antigen-reactive naive T cells from being activated by antigen-presenting DCs, resulting in specific immune suppression and tolerance.

BeStSel: a web server for accurate protein secondary structure prediction and fold recognition from the circular dichroism spectra.

Abstract: Circular dichroism (CD) spectroscopy is a widely used method to study the protein secondary structure. However, for decades, the general opinion was that the correct estimation of β-sheet content is challenging because of the large spectral and structural diversity of β-sheets. Recently, we showed that the orientation and twisting of β-sheets account for the observed spectral diversity, and developed a new method to estimate accurately the secondary structure (PNAS, 112, E3095). BeStSel web server provides the Beta Structure Selection method to analyze the CD spectra recorded by conventional or synchrotron radiation CD equipment. Both normalized and measured data can be uploaded to the server either as a single spectrum or series of spectra. The originality of BeStSel is that it carries out a detailed secondary structure analysis providing information on eight secondary structure components including parallel-β structure and antiparallel β-sheets with three different groups of twist. Based on these, it predicts the protein fold down to the topology/homology level of the CATH protein fold classification. The server also provides a module to analyze the structures deposited in the PDB for BeStSel secondary structure contents in relation to Dictionary of Secondary Structure of Proteins data. The BeStSel server is freely accessible at http://bestsel.elte.hu.