Hiroshi Shikata

Learn More
An attempt was made to purify a porcine skeletal muscle enzyme catalyzing the formation of thiamin triphosphate (TTP) from thiamin diphosphate (TDP), requiring ATP, Mg2+ and a cofactor (creatine). As the purification proceeded, the reaction requirements for ATP and creatine were lost and then a requirement for ADP was manifested. The activity responsible(More)
Age-related changes in the content of non-reducible crosslink amino acids, pyridinoline and histidinoalanine, in rat mandibular bone were studied. The pyridinoline content markedly increased up to 12 months of age and thereafter slightly increased. The histidinoalanine content was low until 3 months of age, but thereafter increased significantly up to 24(More)
BACKGROUND A computerized 48-channel mapping system was used to investigate the characteristics of an atrial epicardial electrogram during chronic atrial fibrillation (AF) in patients with solitary mitral valve disease. We have devised a simple left atrial procedure to eliminate the chronic AF during a mitral valve operation. METHODS Using this mapping(More)
The susceptibility of vitronectin (Vn) purified from human plasma to digestion by matrix metalloproteinases (MMPs) was examined. MMP-2, -3, -7 and -9 except for MMP-1 degraded Vn into multiple fragments. MMP-7 showed the highest activity to the substrate among these MMPs, digesting 8-, 30- and 44-fold more preferentially than MMP-2, -3, and -9,(More)
A full-length cDNA clone for the human prepro alpha 1(I) chain of type I procollagen was characterized. Nucleotide sequencing of the first 1500 nucleotide residues of the 5'-end of the cDNA clone provided 729 nucleotide residues and the codons for 243 amino acid residues not previously defined from any species. The data made it possible, for the first time,(More)
OBJECTIVE Both blood flow monitoring and pressure monitoring are necessary to avoid inadequate cerebral perfusion during cardiovascular operations. Inasmuch as transcranial Doppler ultrasonography does not provide a consistently good signal, especially during cardiopulmonary bypass, we examined the blood flow through the central retinal artery, which has(More)
BACKGROUND We evaluated clinical relevance of orbital ultrasound (OUS) monitoring to neurological events in aortic surgery associated with selective cerebral perfusion (SCP). METHODS In 24 consecutive cases, blood flow was monitored at central retinal artery (CRA) and retrobulbar vessels. The threshold perfusion pressure for detecting CRA flow in the(More)
In relation to a high activity of thiamin diphosphate (TDP) kinase (Koyama, S. et al. (1985) Biochem. Int. 11, 371-380) in the skeletal muscle of pigs and guinea pigs, the content of thiamin phosphate esters in tissues of these animals has been determined by the method of high-performance liquid chromatography. An extremely high concentration of thiamin(More)
Adenylate kinase isozyme 1 (AK1) catalyzes thiamin triphosphate (TTP) formation from thiamin diphosphate (TDP) and ADP. The properties of the TTP-synthesizing activity of purified AK1 from porcine skeletal muscle were studied. The activity was found to require TDP, ADP, and Mg2+, and ATP was only 14.4% as active as ADP. Thiamin monophosphate (TMP) and(More)