Publications by authors named "Hisao Kato"

An understanding of electrochemical dynamics at solid-liquid interfaces is essential to develop advanced batteries and fuel cells and so on. For example, an atomic-level understanding of electrochemical Pt dissolution and redeposition behavior is crucial for optimizing the material design and operating conditions of polymer electrolyte fuel cells (PEFCs). This understanding enables the prevention of the degradation of Pt nanoparticles used as electrocatalysts.

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Tissue factor pathway inhibitor (TFPI) is an anticoagulant protease inhibitor that inhibits the tissue factor-initiated blood coagulation cascade reactions. Based on these anticoagulant functions of TFPI, we hypothesized that genetic variations in TFPI may alter the TFPI expression or impair the anticoagulant function and could predispose persons to deep vein thrombosis (DVT). This study was undertaken to examine whether the genetic polymorphisms in TFPI are associated with the plasma TFPI levels and risk for DVT.

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In this study, we investigate whether the combination of HVJ-AVE liposome-mediated TFPI gene transfer and recombinant TFPI (rTFPI) irrigation would reduce restenosis safely and more effectively. The results indicated that at 4 weeks after angioplasty, the MLD, EELA, IELA and LA of TFPI group and rTFPI group were markedly greater than those of the control groups, and those in the combination group were even greater. The mean IA, I/M, and the percentage of stenosis in TFPI gene group and rTFPI group were significantly reduced compared with control groups, and those in the combination group were even further reduced.

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This study assessed markers of vascular endothelial cell dysfunction associated with early atherosclerosis in carotid arteries. We measured the plasma levels of free-form tissue factor pathway inhibitor (free TFPI), plasminogen activator inhibitor-1 (PAI-1), and von Willebrand factor (vWF) in 522 adults without cardiovascular disease enrolled in the Suita Study. For each sex, we analyzed the association of the degree of intimal-medial thickness (IMT) with hemostatic markers using logistic regression analysis considering potential confounding risk factors, including age, body mass index, lifestyle (current smoking and drinking), illness (diabetes mellitus and hyperlipidemia), systolic blood pressure, and antihypertensive drug use.

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BEta(2)-glycoprotein I (beta(2)-GPI) is proteolytically cleaved by plasmin in domain V (nicked beta(2)-GPI), being unable to bind to phospholipids. This cleavage may occur in vivo and elevated plasma levels of nicked beta(2)-GPI were detected in patients with massive plasmin generation and fibrinolysis turnover. In this study, we report higher prevalence of elevated ratio of nicked beta(2)-GPI against total beta(2)-GPI in patients with ischemic stroke (63%) and healthy subjects with lacunar infarct (27%) when compared to healthy subjects with normal findings on magnetic resonance imaging (8%), suggesting that nicked beta(2)-GPI might have a physiologic role beyond that of its parent molecule in patients with thrombosis.

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Tissue factor pathway inhibitor (TFPI) is a Kunitz-type protease inhibitor that regulates tissue factor-triggered blood coagulation. It has previously been reported that TFPI inhibits the proliferation of human umbilical vein endothelial cells (HUVECs), suggesting that TFPI may act as more than just a mediator of coagulation through changes in gene expression. By using DNA-array techniques and Northern blot analysis, we here revealed that TFPI transiently induced the mRNA expression of JUNB and GADD45B.

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Objective: Tissue factor pathway inhibitor (TFPI), as a primary inhibitor of TF-induced coagulation, reduces neointimal formation and luminal stenosis by inhibiting coagulation and thrombosis after vessel wall injury. Here, we investigated the effect of TFPI gene delivery with a HVJ-AVE liposome vector on restenosis in atherosclerotic arteries after angioplasty in rabbits. We also evaluated the safety of the novel gene therapeutic strategy to prevent restenosis.

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To clarify the mechanism of interaction between chaperonin GroEL and substrate proteins, we studied the conformational changes; of the fifth domain of human beta(2)-glycoprotein I upon binding to GroEL. The fifth domain has a large flexible loop, containing several hydrophobic residues surrounded by positively charged residues, which has been proposed to be responsible for the binding of beta(2)-glycoprotein I to negatively charged phospholipid membranes. The reduction by dithiothreitol of the three intramolecular disulfide bonds of the fifth domain was accelerated in the presence of stoichiometric amounts of GroEL, indicating that the fifth domain was destabilized upon interaction with GroEL.

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Tissue factor pathway inhibitor (TFPI) is a heparin-binding protein involved in the extrinsic blood coagulation system. In order to elucidate the minimal size of heparin chain required for the interaction with TFPI, we prepared a series of heparin-derived oligosaccharides with tailored chain length ranged from disaccharide to eicosasaccharide after the successive treatments of heparin, including partial N-desulphation, deaminative cleavage with nitrous acid and gel-filtration. Affinity chromatography study of each oligosaccharide fraction using TFPI as the ligand indicated that increasing the degree of polymerisation causes increased affinity, and that a remarkable change in the affinity occurs between the decamers and dodecamers.

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Background: Tissue factor pathway inhibitor (TFPI) has anti-proliferative and anti-migratory effects on cultured smooth muscle cells (SMC) in addition to its anti-thrombotic activity. Here, we assess how long locally delivered recombinant TFPI (rTFPI) remains detectable at the delivery sites and clarify the main mechanism by which rTFPI blocks neointimal growth in vivo.

Methods: The iliac arteries of 85 Japanese white rabbits were injured using a Cutting Balloon.

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We identified genes that were differentially expressed between spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) using cDNA microarray analysis, and analyzed the correlation between these genes and hypertension. Twenty four genes were found to be up-regulated and 20 were down-regulated in SHR. We selected 11 genes (6 up-regulated genes: SAH, Hsp70, MCT1, RBP, IDI1, Prion; and 5 down-regulated genes: Thrombin, Dyn, SOD3, Ela1, Gst Y(b)) and subjected them to an F2 cosegregation analysis.

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Tissue factor pathway inhibitor (TFPI) is a Kunitz-type protease inhibitor that inhibits the initial reactions of blood coagulation. A major pool of TFPI is the form associated with the surface of endothelial cells, which is speculated to play an important role in regulating the functions of vascular wall cells. TFPI consists of 3 tandem Kunitz inhibitor domains, the first and second of which inhibit the tissue factor-factor VIIa complex and factor Xa, respectively.

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beta(2)-Glycoprotein I (beta(2)-GPI) is a plasma protein that binds to negatively charged substances such as DNA, heparin, and anionic phospholipids. The interaction of beta(2)-GPI with anionic phospholipids is intriguing in the context of the autoimmune disease antiphospholipid syndrome. To extend understanding of the binding mechanism to phospholipids, the interactions of beta(2)-GPI with amphiphiles, i.

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Tissue factor pathway inhibitor (TFPI) inhibits the activity of coagulation factor VIIa and Xa through its K1 and K2 domain, respectively, and the inhibitory activity is enhanced by heparin. The function of the K3 domain of TFPI has not been established, but the domain probably harbors a heparin binding site (HBS-2). We determined the three-dimensional solution structure of the TFPI K3 domain (Glu182-Gly242) by heteronuclear multidimensional NMR.

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