A tapered undulator beamline BL36XU was constructed at SPring-8 to conduct structural and electronic analysis of dynamic events on polymer electrolyte fuel cell (PEFC) cathode catalysts for the ...development of next-generation PEFCs. BL36XU provides various time and spatially resolved XAFS techniques in an energy range from 4.5 to 35 keV for investigating PEFCs under the operating conditions. In addition, we developed in-situ complementary measurement systems, such as in-situ time-resolved XAFS XRD and ambient pressure HAXPES systems. This report describes the performance and present status of the BL36XU.
The newly installed BL28XU beamline at SPring‐8 is dedicated to in situ structural and electronic analysis of rechargeable batteries. It supports the time range (1 ms to 100 s) and spatial range (1 ...µm to 1 mm) needed for battery analysis. Electrochemical apparatus for battery charging and discharging are available in experimental hutches and in a preparation room. Battery analysis can be carried out efficiently and effectively using X‐ray diffraction, X‐ray absorption fine‐structure analysis and hard X‐ray photoelectron spectroscopy. Here, the design and performance of the beamline are described, and preliminary results are presented.
We are currently constructing a new X-ray absorption fine structure (XAFS) beamline BL36XU at SPring-8 dedicated for the structural and electronic analysis of the dynamic events on polymer ...electrolyte fuel cell (PEFC) cathode catalysts for the development of next-generation PEFCs. To investigate the cathode catalyst nanoparticles in PEFCs under the operating conditions, the beamline is designed to provide time- and spatially resolved XAFS techniques having a time resolution of 100 μs, spatial resolution of 200 nm, and depth resolution of 1 μm. We report the outline and design of the new beamline.
Abstract
BACKGROUND
Several reports from basic researches and clinical studies have suggested that xanthine oxidase (XO) inhibitors have suppressive effects on cardiovascular diseases. However, the ...roles of a XO inhibitor, febuxostat (FEB), in the pathogenesis of vascular remodeling and hypertension independent of the serum uric acid level remain unclear.
METHODS
To induce vascular remodeling in mice, angiotensin II (Ang II) was infused for 2 weeks with a subcutaneously implanted osmotic minipump. FEB was administered every day during Ang II infusion. Aortic fibrosis was assessed by elastica van Gieson staining. Mouse macrophage RAW264.7 cells (RAW) and mouse embryonic fibroblasts were used for in vitro studies.
RESULTS
FEB suppressed Ang II-induced blood pressure elevation and aortic fibrosis. Immunostaining showed that Ang II-induced macrophage infiltration in the aorta tended to be suppressed by FEB, and XO was mainly colocalized in macrophages, not in fibroblasts. Transforming growth factor-β1 (TGF-β1) mRNA expression was induced in the aorta in the Ang II alone group, but not in the Ang II + FEB group. Ang II induced α-smooth muscle actin-positive fibroblasts in the aortic wall, but FEB suppressed them. XO expression and activity were induced by Ang II stimulation alone but not by Ang II + FEB in RAW. FEB suppressed Ang II-induced TGF-β1 mRNA expression in RAW.
CONCLUSIONS
Our results suggested that FEB ameliorates Ang II-induced aortic fibrosis via suppressing macrophage-derived TGF-β1 expression.
The molecular pharmacology of inhalational anesthetics remains poorly understood. Despite accumulating evidence suggesting that neuronal membrane proteins are potential targets of inhaled ...anesthetics, most currently favored membrane protein targets lack any direct evidence for anesthetic binding. We report herein the location of the binding site for the inhaled anesthetic halothane at the amino acid residue level of resolution in the ligand binding cavity in a prototypical G protein-coupled receptor, bovine rhodopsin. Tryptophan fluorescence quenching and direct photoaffinity labeling with (14)Chalothane suggested an interhelical location of halothane with a stoichiometry of 1 (halothane/rhodopsin molar ratio). Radiosequence analysis of (14)Chalothane-labeled rhodopsin revealed that halothane contacts an amino acid residue (Trp265) lining the ligand binding cavity in the transmembrane core of the receptor. The predicted functional consequence, competition between halothane and the ligand retinal, was shown here by spectroscopy and is known to exist in vivo. These data suggest that competition with endogenous ligands may be a general mechanism of the action of halothane at this large family of signaling proteins.
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