Publications (4)3.36 Total impact
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Article: Inhibitory effect of statins on inflammatory cytokine production from human bronchial epithelial cells.
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ABSTRACT: Statins are 3-hydroxy-3-methylglutaryl-co-enzyme A reductase inhibitors of cholesterol biosynthesis, and have been reported to exert pleiotropic effects on cellular signalling and cellular functions involved in inflammation. Recent reports have demonstrated that previous statin therapy reduced the risk of pneumonia or increased survival in patients with community-acquired pneumonia. However, the precise mechanisms responsible for these effects are unclear. In the present study, we examined the effects of statins on cytokine production from lipopolysaccharide (LPS)-stimulated human bronchial epithelial cells (BEAS-2B). Interleukin (IL)-6 and IL-8 mRNA expression and protein secretion in LPS-stimulated cells were inhibited significantly by the lipophilic statin pitavastatin and the hydrophilic statin pravastatin. As these inhibitory effects of statin were negated by adding mevalonate, the anti-inflammatory effects of statins appear to be exerted via the mevalonic cascade. In addition, the activation levels of Ras homologue gene family A (RhoA) in BEAS-2B cells cultured with pitavastatin were significantly lower than those without the statin. These results suggest that statins have anti-inflammatory effects by reducing cytokine production through inhibition of the mevalonic cascade followed by RhoA activation in the lung.Clinical & Experimental Immunology 05/2012; 168(2):234-40. · 3.36 Impact Factor -
Article: Belle II Technical Design Report
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ABSTRACT: The Belle detector at the KEKB electron-positron collider has collected almost 1 billion Y(4S) events in its decade of operation. Super-KEKB, an upgrade of KEKB is under construction, to increase the luminosity by two orders of magnitude during a three-year shutdown, with an ultimate goal of 8E35 /cm^2 /s luminosity. To exploit the increased luminosity, an upgrade of the Belle detector has been proposed. A new international collaboration Belle-II, is being formed. The Technical Design Report presents physics motivation, basic methods of the accelerator upgrade, as well as key improvements of the detector. Comment: Edited by: Z. Dole\v{z}al and S. Uno11/2010; -
Article: Adsorption of nitrogen and ammonia by polycrystalline iron surfaces in the temperature range 80–290 K studied by electron spectroscopy
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ABSTRACT: X-ray and uv induced photoelectron spectroscopy have provided information on the various molecular states of nitrogen formed on polycrystalline iron surfaces from dinitrogen and ammonia. At 85 K two distinct states are observed with N2(g) which have N(1s) binding energy values of 405.3 and 400.2 eV. These are in equilibrium with N2(g), are weakly held, and are desorbed on warming to 290 K leaving a nitrogen free surface. The two states are assigned to a molecularly adsorbed and linear species the former characterised by an N(1s) value of 400.2 eV and the latter by 405.3 eV. At 290 K nitrogen is adsorbed with a very low sticking probability (⩽10−6) giving rise to an N(1s) value of 397.2 eV. This is undoubtedly the dissociatively chemisorbed species. At a nitrogen pressure of l Torr adsorption is “instantaneous” and the N(1s) value is 397 eV. No evidence for the unstable bridged and linear forms of nitrogen is obtained at 290 K although they may well be precursors to the formation of the strongly chemisorbed nitrogen species. Shifts in the N(1s) binding energy induced by subsequent oxygen adsorption are discussed briefly. At 85 K ammonia adsorbs largely in the molecular form with a broad N(1s) peak centred at about 400 eV but on warming to 290 K this splits to give two peaks one at 397 eV and the other at 400 eV. Interaction at 290 K leads to a dominant peak at 397.2 eV and a subidiary one at 400 eV. Helium (1) spectra support the assignment of the 397.2 eV peak to dissociated species (N, NH) and the 400 eV peak to molecular adsorption. The conclusions with N2 and NH3 are substantiated further by comparing the data with results for nitric oxide. The concentration of nitrogen adatom species formed from NO at 290 K and 10−6 Torr is some ten times that formed from N2 at 1 Torr and three times that from NH3 at 10−6 Torr and the same temperature.Surface Science. -
Article: Growth of ultra-thin titanium oxide on Cu(100), Fe/Cu(100) and ordered ultra-thin iron oxide studied by low-energy electron diffraction and X-ray photoelectron spectroscopy
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ABSTRACT: The growth, structure and chemical state of ultra-thin titanium oxide prepared on Cu(100), Fe/Cu(100) and on ultra-thin iron oxide have been investigated using X-ray photoelectron spectroscopy (XPS) and low-energy electron diffraction (LEED). The titanium oxide on Cu(100) was prepared by evaporating titanium atoms on the oxygen chemisorbed substrate, followed by heating at 623 K in 1×10−5 Pa O2. Up to one layer coverage the titanium oxide showed a chemical shift of the Ti 2p3/2 peak corresponding to Ti4+ and a LEED pattern of a hexagonal structure with two domains rotated 90° with respect to each other. The oxide has been proposed to consist of oxygen–titanium–oxygen trilayers with the stoichiometry of TiO2. The surface structure was unstable at higher coverage. The same structure of titanium oxide overlayer was prepared by evaporating titanium atoms on 1.7 ML Fe/Cu(100), followed by oxidation under the condition to give the FeO(111) underlayers consisting of two iron–oxygen bilayers. The ordered titanium oxide on FeO(111)/Cu(100) was prepared also by evaporating titanium atoms on an ordered Fe3O4/Cu(100) surface, followed by heating at 623 K in vacuum. The ordered structure of the titanium oxide was not stable on the iron oxide at higher oxidation state.Surface Science.
