Hiroki Takeyama

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OBJECTIVE Destruction of the extracellular matrix is essential for tumor invasion and metastasis. The relationship between Helicobacter pylori (H. pylori) infection and destruction of the extracellular matrix is not yet clear. Urokinase-type plasminogen activator (uPA) plays an important role in the destruction of the extracellular matrix and basement(More)
VEGF is a highly specific stimulator of endothelial cells and may play an important role in angiogenesis in the process of tissue regeneration. We previously showed that cyclooxygenase-2 (COX-2) expressed in mesenchymal cells of the ulcer bed is involved in the ulcer repair process. To clarify the role of COX-2 in angiogenesis during gastric ulcer healing,(More)
A sulfur-containing amino acid compound, S-allyl cysteine (SAC), derived from garlic extract inhibited proliferation of nine human and murine melanoma cell line in a dose-dependent manner (1.2-10 mM) assessed by a [3H]thymidine incorporation assay. Three control human lymphoblastoid cell lines were not inhibited by SAC concentrations < 5 mM. Four human(More)
In the present study, the effects of a selective Rho-associated coiled-coil forming protein kinase (ROCK) inhibitor, Y-27632 [(+)-(R)-trans-4-(1-aminoethyl)-(4-pyridyl)cyclohexanecarboxamide dihydrochloride] on acetylcholine-induced contraction and Ca(2+) sensitization of rat bronchial smooth muscle were examined. Intact and beta-escin-permeabilized muscles(More)
In acute inflammatory condition, little is known about the expression of the urokinase-type plasminogen activator (uPA) and its receptor (uPAR) in the gastric fibroblasts. To clarify the role of human gastric fibroblasts in acute inflammatory conditions such as gastric ulcer, the effects of interleukin (IL)-1beta and tumor necrosis factor (TNF)-alpha on the(More)
Prostaglandin E(2) (PGE(2)) is thought to play an important role in both inflammatory and anti-inflammatory effects. The effect of PGE(2) on the proinflammatory chemokine interleukin-8 (IL-8) in the gastric epithelial cells has not been defined yet. A gastric cancer cell line (MKN45) and primary gastric fibroblasts were cocultured with Helicobacter pylori(More)
Pig zona pellucida (ZP) contains three families of glycoproteins: PZP2, PZP3 alpha and PZP3 beta. PZP3 alpha mediates the binding of the ZP to spermatozoa. In this study, the binding site of pig ZP on boar spermatozoa and the zona-binding proteins of boar spermatozoa were studied using chemically modified zona glycoproteins or anti-pig ZP antiserum.(More)
Smooth muscle responsiveness of intrapulmonary small bronchi obtained from repeatedly antigen-challenged rats was compared with that from control animals to determine whether smooth muscle contractility of peripheral airways is augmented by such repeated challenge. In intact (non-permeabilized) smooth muscles of intrapulmonary bronchi, the acetylcholine(More)
In this study we demonstrated that fetal calf serum (FCS) depleted of IgG by protein G affinity chromatography (G-FCS) is superior to whole FCS or serum-free culture media as a culture supplement for the production of purified IgG monoclonal antibodies (MAb). One hundred ml FCS was applied to a 25 ml protein G Sepharose 4 Fast Flow Column, which was shaken(More)