Tatsuya Hayashi

Mie University, Tsu-shi, Mie-ken, Japan

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Publications (36)136.85 Total impact

  • Article: The thrombin inhibitor, argatroban, inhibits breast cancer metastasis to bone.
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    ABSTRACT: BACKGROUND: Breast cancer has the potential to metastasize to bone, causing debilitating symptoms. Although many tumor cells have thrombin-generating systems originating from tissue factor (TF), therapy in terms of the coagulation system is not well established. To elucidate the efficacy of the thrombin inhibitor, argatroban, on bone metastasis, we investigated TF activation and vascular endothelial growth factor (VEGF) secretion on treatment with thrombin and argatroban. METHODS: MDA-231 breast cancer cells were treated with thrombin in presence or absence of argatroban, and TF activity was measured in the form of activated factor X. Enzyme-linked immunosorbent assay (ELISA) was used to measure VEGF concentrations in the medium. MDA-231 cells were injected into the left heart ventricle of mice, and then argatroban or saline was administered intraperitoneally for 28 days. After 28 days, incidence of bone metastasis was evaluated in the limbs by radiography. RESULTS: TF activity and VEGF secretion were upregulated by thrombin. Argatroban inhibited the enhancement of TF activity and VEGF secretion induced by thrombin. In vivo analysis revealed that the number of metastasized limbs in the argatroban group was significantly lower compared with the saline group (P < 0.05). CONCLUSIONS: Thrombin not only enhances VEGF secretion but also has a positive feedback mechanism to reexpress TF. These results indicate that inhibition of thrombin is of great value in suppression of tumor metastasis. Argatroban is a noteworthy and useful thrombin inhibitor because it has already been used in the clinical setting and has antimetastatic effects in vivo.
    Breast Cancer 02/2012; · 1.36 Impact Factor
  • Article: Effect of a prostaglandin I(2) analog on the expression of thrombomodulin in liver and spleen endothelial cells after an extensive hepatectomy.
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    ABSTRACT: Dysfunction of the remnant liver after a hepatectomy is caused by microthrombus formation due to endothelial cell (EC) damage. This study evaluated the effect of prostaglandin I(2) (PGI(2)) on the expression of thrombomodulin (TM), a marker for the anticoagulant properties of ECs, using cultured human umbilical vein endothelial cells (HUVECs), and using a canine extensive hepatectomy model. The presence of PGI(2) receptors was confirmed on HUVECs by reverse transcription-polymerase chain reaction, and the effect of the PGI(2) analog on TM expression on HUVECs was determined by an enzyme-linked immunosorbent assay. Twenty mongrel dogs were divided into four groups comprising a sham operation, 70% hepatectomy, 84% hepatectomy, and 84% hepatectomy, with the administration of the PGI(2) analog, respectively, and TM expression in the liver, spleen, pancreas, kidney, lung, portal vein, and intestine was determined immunohistochemically. The TM expression on HUVECs was upregulated by the PGI(2) analog. The TM expression on ECs in the hepatic sinusoids and splenic sinus were markedly decreased after the 84% hepatectomy, but such damage was markedly mitigated following an 84% hepatectomy with administration of the PGI(2) analog. An extensive hepatectomy induced severe EC damage not only in the hepatic sinusoids but in the splenic sinuses as well. Prostaglandin I(2) prevented damage to these ECs, suggesting that PGI(2) improves the microcirculation in the remnant liver.
    Surgery Today 02/2011; 41(2):230-6. · 1.22 Impact Factor
  • Article: Phosphoinositide 3-kinase induced activation and cytoskeletal translocation of protein kinase CK2 in protease activated receptor 1-stimulated platelets.
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    ABSTRACT: CK2 is a highly conserved protein kinase involved in several cellular events. CK2 is expressed in platelets but its role in platelet activation remains poorly understood. In the present study, we tested the hypothesis that CK2 plays a role in platelet activation, particularly in the PAR1-dependent signal transduction pathway. The effect of CK2 and PI 3-kinase inhibitors on aggregation of platelets, activation of GPIIb/IIIa, activation and translocation of CK2 was examined. Platelets were incubated with the cell permeable CK2 inhibitors, DRB, DMAT and TBB and stimulated with the PAR1-AP (SFLLRNP). CK2 inhibitors showed the specific inhibitory pattern of platelet aggregation, characterized by a primary phase of aggregation followed by progressive disaggregation. CK2 inhibitors suppressed the activation of GPIIb/IIIa. PAR1-AP induced two-fold increase in CK2 activity and stimulated the translocation of CK2 from Triton X-100-soluble to -insoluble fraction. Preincubation of platelets with the PI 3-kinase inhibitor, wortmannin or LY294002, impaired PAR1-AP-induced aggregation of platelets. PAR1-AP-induced increase in CK2 activity and translocation of CK2 were inhibited by these treatments. Taken together, the present study demonstrated, for the first time, that PI 3-kinase-CK2 pathway plays an important role in the mechanism of PAR1-dependent platelet aggregation.
    Thrombosis Research 11/2010; 126(6):511-6. · 2.44 Impact Factor
  • Article: Connexin32 protects against vascular inflammation by modulating inflammatory cytokine expression by endothelial cells.
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    ABSTRACT: Gap junctions (GJs) play an important role in vascular function, stability, and homeostasis in endothelial cells (ECs), and GJs are comprised of members of the connexin (Cx) family. GJs of vascular ECs are assembled from Cx37, Cx40, and Cx43, and we showed that ECs also express Cx32. In this study, we investigated a potential role for Cx32 during vascular inflammation. Expression of Cx32 mRNA and protein by human umbilical venous ECs (HUVECs) decreased following treatment with tumor necrosis factor (TNF)-α, but lipopolysaccharide (LPS) and interleukin (IL)-1β did not affect Cx32 expression. Intracellular transfer of an inhibitory anti-Cx32 monoclonal antibody significantly enhanced TNF-α-induced monocyte chemotactic protein (MCP)-1 and IL-6 expression, but overexpression of Cx32 abrogated TNF-α-induced MCP-1 and IL-6 expression. LPS treatment of Cx32 knock-out mice significantly increased the serum concentrations of TNF-α, interferon-γ, IL-6 and MCP-1, compared to wild-type littermate mice. These data suggest that Cx32 protects ECs from inflammation by regulating cytokine expression and plays an important role in the maintenance of vascular function.
    Experimental Cell Research 10/2010; 317(3):348-55. · 3.58 Impact Factor
  • Article: The cytoprotective effects of addition of activated protein C into preservation solution on small-for-size grafts in rats.
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    ABSTRACT: Small-for-size liver grafts are a serious obstacle for partial orthotopic liver transplantation. Activated protein C (APC), a potent anticoagulant serine protease, is known to have cell-protective properties due to its anti-inflammatory and antiapoptotic activities. This study was designed to examine the cytoprotective effects of a preservation solution containing APC on small-for-size liver grafts, with special attention paid to ischemia-reperfusion injury and shear stress in rats. APC exerted cytoprotective effects, as evidenced by (1) increased 7-day graft survival; (2) decreased initial portal pressure and improved hepatic microcirculation; (3) decreased levels of aminotransferase and improved histological features of hepatic ischemia-reperfusion injury; (4) suppressed infiltration of neutrophils and monocytes/macrophages; (5) reduced hepatic expression of tumor necrosis factor alpha and interleukin 6; (6) decreased serum levels of hyaluronic acid, which indicated attenuation of sinusoidal endothelial cell injury; (7) increased hepatic levels of nitric oxide via up-regulated hepatic endothelial nitric oxide synthesis expression together with down-regulated hepatic inducible nitric oxide synthase expression; (8) decreased hepatic levels of endothelin 1; and (9) reduced hepatocellular apoptosis by down-regulated caspase-8 and caspase-3 activities. These results suggest that a preservation solution containing APC is a potential novel and safe product for small-for-size liver transplantation, alleviating graft injury via anti-inflammatory and antiapoptotic effects and vasorelaxing conditions.
    Liver Transplantation 01/2010; 16(1):1-11. · 3.39 Impact Factor
  • Article: An in vitro method for screening anti-platelet agents using a microchannel array flow analyzer.
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    ABSTRACT: New in vitro methods are desirable for the analysis of platelet aggregation and screening novel anti-platelet agents using whole blood. To this end, we examined platelet aggregation and thrombus formation in whole human blood from healthy volunteers using a microchannel array flow analyzer (MC-FAN). Platelet aggregation in whole blood, treated with the activating agents ADP, collagen or ristocetin was detected in the MC-FAN by measuring the decrease in flow rate as a function of agent concentration. The results were compared with aggregation in platelet rich plasma (PRP) in a conventional aggregometer, as measured by the increase in optical density. The MC-FAN detected platelet aggregation in whole blood at two- to four-fold lower concentrations of agonist compared to those in PRP in the aggregometer. Anti-platelet agents attenuated the decrease in blood flow rate in the MC-FAN by inhibiting fibrin formation and platelet aggregation, but anticoagulants only inhibited fibrin formation and did not affect blood flow rates. These findings suggest that the MC-FAN system may be a useful method for the evaluation of platelet activation and facilitate the development of novel anti-platelet agents.
    Biorheology 01/2010; 47(2):153-61. · 1.93 Impact Factor
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    Article: LPS-Toll-Like Receptor-Mediated Signaling on Expression of Protein S and C4b-Binding Protein in the Liver.
    Tatsuya Hayashi, Koji Suzuki
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    ABSTRACT: Protein S (PS), mainly synthesized in hepatocytes and endothelial cells, plays a critical role as a cofactor of anticoagulant activated protein C (APC). PS activity is regulated by C4b-binding protein (C4BP), structurally composed of seven α-chains (C4BPα) and a β-chain (C4BPβ). In this paper, based primarily on our previous studies, we review the lipopolysaccharide (LPS)-induced signaling which affects expression of PS and C4BP in the liver. Our in vivo studies in rats showed that after LPS injection, plasma PS levels are significantly decreased, whereas plasma C4BP levels first are transiently decreased after 2 to 12 hours and then significantly increased after 24 hours. LPS decreases PS antigen and mRNA levels in both hepatocytes and sinusoidal endothelial cells (SECs), and decreases C4BP antigen and both C4BPα and C4BPβ mRNA levels in hepatocytes. Antirat CD14 and antirat Toll-like receptor (TLR)-4 antibodies inhibited LPS-induced NFκB activation in both hepatocytes and SECs. Furthermore, inhibitors of NFκB and MEK recovered the LPS-induced decreased expression of PS in both cell types and the LPS-induced decreased expression of C4BP in hepatocytes. These data suggest that the LPS-induced decrease in PS expression in hepatocytes and SECs and LPS-induced decrease in C4BP expression in hepatocytes are mediated by MEK/ERK signaling and NFκB activation and that membrane-bound CD14 and TLR-4 are involved in this mechanism.
    Gastroenterology Research and Practice 01/2010; 2010. · 0.98 Impact Factor
  • Article: Activated protein C stimulates osteoblast proliferation via endothelial protein C receptor.
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    ABSTRACT: Bone is continually remodeled by the action of osteoblasts, osteocytes, and osteoclasts. Resting osteoblasts are able to proliferate and differentiate into mature osteoblasts when physiologically required, as after tissue injury. Activated protein C (APC) is a serine protease that functions in anticoagulation, anti-inflammation, anti-apoptosis, cell proliferation, and wound repair. In this study, we examined the effect of APC on osteoblast proliferation and differentiation. We examined the presence of protein C in human fracture hematoma by immunohistochemical staining. We then evaluated the effect of APC, diisopropyl fluorophosphate-inactivated APC (DIP-APC) or protein C zymogen on normal human osteoblast (NHOst) proliferation using tetrazolium salt assay in the presence or absence of aprotinin, hirudin, protein C, antibody against protein C, endothelial protein C receptor (EPCR) or protease-activated receptor (PAR)-1. Finally, activation of p44/42 MAP kinase was evaluated by Western blot analysis. Both APC and DIP-APC increased osteoblast proliferation in a dose-dependent manner, while protein C did not. The APC-induced increased proliferation of osteoblast was not affected by aprotinin, hirudin, and anti-protein C antibody which inhibits the protease activity of APC. Treatment with protein C or anti-EPCR antibody which inhibits APC binding to EPCR inhibited APC-mediated osteoblast proliferation, while treatment with anti-PAR-1 antibody did not. APC promoted the phosphorylation of p44/42 MAP kinase within osteoblasts; this effect was inhibited by the anti-EPCR antibody. APC stimulates osteoblast proliferation by activating p44/42 MAP kinase through a mechanism that requires EPCR but not PAR-1 or the proteolytic activity of APC. APC generated at fracture sites may contribute to fracture healing by promoting osteoblast proliferation.
    Thrombosis Research 10/2009; 125(2):184-91. · 2.44 Impact Factor
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    Article: Connexin32 is expressed in vascular endothelial cells and participates in gap-junction intercellular communication.
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    ABSTRACT: Endothelial cells (ECs) play many roles in vascular biology, including control of blood pressure, blood clotting, atherosclerosis, angiogenesis, and inflammation. Gap junctions (GJs) are channel-like assemblies of connexin (Cx) family proteins that connect neighboring cells and modulate and synchronize their intracellular environments by the transfer of intracellular mediators. It has been reported that vascular ECs express Cx37, Cx40, and Cx43, but not Cx32. Here, we showed that Cx32 mRNA and protein are expressed in various cultured human ECs. We confirmed Cx32 expression in blood vessel ECs using wild-type and Cx32 knock-out mice. We observed that dye transfer between cultured ECs through gap junctions is suppressed by an anti-Cx32 monoclonal antibody. These findings suggest that vascular ECs express Cx32, which participates in endothelial gap-junction intercellular communication.
    Biochemical and Biophysical Research Communications 06/2009; 382(2):264-8. · 2.48 Impact Factor
  • Article: Role of the coagulation system in allergic inflammation in the upper airways.
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    ABSTRACT: Thrombin has been detected and demonstrated to play a role in the airways of patients with bronchial asthma, but its role in the upper airways including during allergic rhinitis is unknown. This study was conducted to explore whether thrombin is presence in the upper airways and, if so, whether it affects mucin secretion. Fifteen patients with allergic rhinitis were enrolled in the clinical study; primary nasal septum epithelial cells and normal bronchial epithelial cells were used for in vitro evaluation, and rats as animal models. Significant concentrations of thrombin were found in nasal secretion after allergic provocation in allergic patients, and thrombin and its agonistic receptor peptide induced significant secretion of mucin in primary nasal cells and normal bronchial epithelial cells as compared to non-stimulated cells. Increased mucosubstance secretion in septum epithelial cells was also induced after nasal instillation of thrombin in rats. Further, the anticoagulant, activated protein C, significantly inhibited thrombin-induced mucin secretion from septum epithelial cells in rats. The results of this study suggest that activation of the coagulation system occurs during the allergic response and that thrombin plays a crucial role in the regulation of mucin production in the upper airways.
    Clinical Immunology 10/2008; 129(2):365-71. · 4.05 Impact Factor
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    Article: Inhibition of nuclear factor-kappaB in T cells suppresses lung fibrosis.
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    ABSTRACT: Cytokines secreted by T cells play a pivotal role in the pathogenesis of lung injury and fibrosis, and the transcription factors nuclear factor (NF)-kappaB and activator protein (AP)-1 are involved in the expression of cytokines from T cells during lung injury. We assessed the potential therapeutic effect of SP100030, a specific inhibitor of T-cell NF-kappaB and AP-1 in lung fibrosis. The effect of SP100030 was evaluated using a mouse model of chronic lung fibrosis. Mice treated with SP100030, as compared with untreated mice, had significantly less cachexia and less lung injury and had decreased levels of inflammatory cytokines and growth factors, decreased activation of coagulation activation, and decreased collagen deposition in the lung. The inhibitory activity of SP100030 was dose dependent and was effective in acute and chronic phases of lung fibrosis. SP100030 inhibited the activation of the protein kinase C-isoform in T-cell lines and suppressed NF-kappaB-driven cytokine expression in CD4(+) and CD8(+) T cells. These results suggest that the specific inhibition of NF-kappaB could be useful for the treatment of lung fibrosis.
    American Journal of Respiratory and Critical Care Medicine 01/2008; 176(12):1251-60. · 11.08 Impact Factor
  • Article: Protein C and its inhibitor in malignancy.
    Koji Suzuki, Tatsuya Hayashi
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    ABSTRACT: Activated protein C (APC) and protein C inhibitor (PCI) are the major components of the anticoagulant protein C pathway. Recently, APC and PCI have been demonstrated to play many roles not only in the regulation of hemostasis but also in cell inflammation, proliferation, apoptosis, tumor cell migration, invasion, and metastasis. Here we summarize the role of APC and PCI in malignancy. APC increases migration of ovarian cancer cells and choriocarcinoma cells in a Transwell invasion assay in the presence of plasminogen activator inhibitor (PAI)-1; this finding suggests that APC stimulates urokinase-type plasminogen activator (uPA) by forming a complex with PAI-1 leading to activation of extracellular matrix proteases and increased invasion. It was recently reported that APC, independent of PAI-1, may increase invasion and chemotaxis of breast cancer cells by activating specific signaling pathways through endothelial protein C receptor (EPCR) and protease-activated receptor (PAR)-1. APC also increased proliferation of vascular endothelial cells and angiogenesis by EPCR-mediated activation of mitogen-activated protein kinase (MAPK), phosphatidylinositol 3-kinase (PI3K), and endothelial nitric oxide synthase (eNOS) pathways. On the other hand, we have previously reported that both uPA and PCI are synthesized in renal proximal tubular epithelial cells (RPTECs) and that PCI expression in RPTEC-derived tumor cells is significantly decreased compared with normal RPTECs. The RPTEC-derived renal carcinoma cell line Caki-1 also showed decreased expression of PCI. PCI inhibited in vitro invasive activity of Caki-1 and breast cancer cells by its protease inhibitory activity. However, PCI was found to inhibit the growth and metastatic potential of breast cancer cells independent of its protease inhibitory activity in severe combined immunodeficient mice. PCI can also inhibit angiogenesis in vivo and in vitro assays independent of its protease inhibitory activity. Overall, these data show that APC promotes tumor cell invasion by EPCR-mediated and PAR-1-mediated protease activity and that PCI inhibits tumor cell invasion in vitro by its protease inhibitory activity and suppresses tumor cell growth, metastasis, and angiogenesis independent of its protease inhibitory activity.
    Seminars in Thrombosis and Hemostasis 11/2007; 33(7):667-72. · 4.52 Impact Factor
  • Article: Intracellular localization of protein C inhibitor (PCI) and urinary plasminogen activator in renal tubular epithelial cells from humans and human PCI gene transgenic mice.
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    ABSTRACT: Urinary plasminogen activator (uPA) is a serine protease that plays important roles in various extracellular proteolytic processes. In humans, protein C inhibitor (PCI) is known to regulate the activity of the serine proteases involved in blood coagulation, wound healing, and tumor metastasis, whereas PCI is not present in murine plasma or tissues other than the reproductive tissues. The large amount of uPA-PCI complexes found in human urine suggests that these complexes are formed in the kidneys. In the present study, we performed immunofluorescence double labeling and electron microscopic immunocytochemistry using renal tissues from humans and human PCI gene transgenic (PCI-TG) mice. In human renal tissues, PCI and uPA colocalized in the cytoplasm of renal proximal tubular epithelial cells (RPTECs), and juxtaposition of PCI and uPA immunoreactive particles was detected in the microvilli and lysosomes in the RPTECs. The intracellular distributions of PCI and uPA in the RPTECs from PCI-TG mice were similar to those observed in human RPTECs. These findings hint at the physiological roles of uPA and PCI in human kidneys, and also suggest that the PCI-TG mice will be useful for evaluating the roles of PCI in human physiological and pathological conditions.
    Histochemie 11/2007; 128(4):293-300. · 2.59 Impact Factor
  • Article: Protein C inhibitor inhibits breast cancer cell growth, metastasis and angiogenesis independently of its protease inhibitory activity.
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    ABSTRACT: Protein C inhibitor (PCI) regulates the anticoagulant protein C pathway and also inhibits urinary plasminogen activator (uPA), a mediator of tumor cell invasion. In the present study, we evaluated the effect of human PCI and its inactive derivatives on tumor growth and metastasis of human breast cancer (MDA-231) cells, and on angiogenesis in vivo. The invasiveness of MDA-231 cells was inhibited by recombinant intact PCI, but not by reactive site-modified PCI (R354APCI) or by the N-terminal fragment of protease-cleaved PCI (NTPCI). The in vitro invasiveness of MDA-231 cells expressing intact PCI (MDA-PCI) was significantly decreased as compared to MDA-231 cells expressing R354APCI (MDA-R354APCI) or NTPCI (MDA-NTPCI). Further, in vivo growth and metastatic potential of MDA-PCI, MDA-R354APCI and MDA-NTPCI cells in severe combined immunodeficient (SCID) mice were significantly decreased as compared to MDA-Mock cells. Angiogenesis was also significantly decreased in Matrigel implant containing MDA-PCI, MDA-R354APCI or MDA-NTPCI cells as compared to that containing MDA-Mock cells. In vivo angiogenesis in rat cornea and in vitro tube formation were also inhibited by recombinant intact PCI, R354APCI and NTPCI. Furthermore, the anti-angiogenic activity of PCI was strong as cleaved antithrombin (AT), and slightly stronger than that of plasminogen activator inhibitor (PAI)-1 and pigment epithelium-derived factor (PEDF). Overall, this study showed that, in addition to a reactive site-dependent mechanism, PCI may also regulate tumor growth and metastasis independently of its protease inhibitory activity by inhibiting angiogenesis.
    International Journal of Cancer 10/2007; 121(5):955-65. · 5.44 Impact Factor
  • Article: The interaction among protein C inhibitor, prostate-specific antigen, and the semenogelin system.
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    ABSTRACT: The kallikrein-like serine protease, prostate-specific antigen (PSA), is mixed in human seminal plasma with its protein substrates semenogelin (Sg) -I, Sg-II, and protein C inhibitor (PCI), which are produced in seminal vesicles. In the seminal plasma, PSA degrades Sg-I, and Sg-II, which are major components in insoluble coagula, and PCI inhibits PSA by forming a PSA-PCI complex. Digestion of seminal coagula with PSA releases PCI and PSA-PCI complex from the coagula into a soluble phase, suggesting the presence of active PCI within the coagula. PCI forms a ternary complex with PSA and Sg-II in the seminal plasma. The binding of Sg-II to PSA and PCI is influenced by pH, ionic strength, heparin, negatively charged dextran sulfate, divalent cations, and particularly by Zn 2 +. These observations suggest that binding of PCI to Sg in seminal vesicles regulates the PSA-catalyzed degradation of Sg in seminal plasma; the complex formation among PCI, PSA, and Sg is modulated by several factors in seminal plasma.
    Seminars in Thrombosis and Hemostasis 03/2007; 33(1):46-52. · 4.52 Impact Factor
  • Article: Deficiency of tenascin C attenuates allergen-induced bronchial asthma in the mouse.
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    ABSTRACT: Tenascin C (TN-C) is an extracellular matrix glycoprotein whose expression is increased in several inflammatory diseases of the lung, including bronchial asthma. However, the exact function of TN-C in the pathogenesis of lung inflammation remains unclear. In the present study, we compared the degree of bronchial asthma in wild-type and TN-C-deficient (-/-) BALB/c mice. Bronchial asthma was induced by sensitization and challenge with ovalbumin. Littermates treated with saline were used as controls. Cytokines in bronchoalveolar lavage fluid and plasma were measured by enzyme immunoassays. The number of eosinophils in the lung was significantly increased in wild-type mice compared with TN-C-knockout mice. Airway hyperreactivity, NF-kappaB activation and concentrations of monocyte chemoattractant protein-1, IL-5, IL-13, metalloproteinase-9 and immunoglobulin-E in the bronchoalveolar lavage fluid were significantly decreased in ovalbumin-sensitized/challenged TN-C-knockout mice compared with their wild-type counterparts. In vitro experiments disclosed that TN-C significantly stimulates the secretion of IL-5, IL-13, IFN-gamma and immunoglobulin-E from spleen lymphocytes. These observations suggest that TN-C is involved in the pathogenesis of bronchial asthma.
    European Journal of Immunology 01/2007; 36(12):3334-45. · 5.10 Impact Factor
  • Article: Decreased protein C activation in patients with fulminant hepatic failure.
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    ABSTRACT: Abnormalities of the blood coagulation system have an influence on outcome in patients with fulminant hepatic failure (FHF). The protein C (PC) pathway is one of the main modulators of the blood coagulation system. The role of the PC pathway in FHF is not clear. In the present study, we evaluated endothelial cell injury and the grade of activated protein C (APC) generation in FHF patients. The effect of APC on the expression of tumor necrosis factor (TNF)-alpha and monocyte chemoattractant protein (MCP)-1 from LI90 stellate cells was also evaluated. This study comprised 5 patients with FHF, 6 with acute hepatitis (AH), 12 with chronic hepatitis (CH) and 20 healthy subjects. The plasma concentrations of thrombin-antithrombin complex and thrombomodulin were significantly increased in FHF patients compared with those in AH patients and healthy subjects. The circulating levels of activated protein C-protein C inhibitor (APC-PCI) complex and the APC-PCI/PC ratio were significantly decreased in patients with FHF compared to healthy controls. APC significantly inhibited in vitro the expression of TNFalpha and MCP-1 from LI90 stellate cells. This study demonstrated enhanced endothelial cell injury in association with decreased PC activation and hypercoagulability in FHF.
    Scandinavian Journal of Gastroenterology 04/2006; 41(3):331-7. · 2.02 Impact Factor
  • Article: [Heparin cofactor II (HCII)].
    Tomoaki Yoshikawa, Tatsuya Hayashi, Koji Suzuki
    Nippon rinsho. Japanese journal of clinical medicine 01/2005; 62 Suppl 12:667-70.
  • Article: [Protein C, protein S, protein Z].
    Yasuhiko Hamada, Tatsuya Hayashi, Koji Suzuki
    Nippon rinsho. Japanese journal of clinical medicine 01/2005; 62 Suppl 12:681-6.
  • Article: [C4b-binding protein].
    Koji Fujii, Tatsuya Hayashi, Koji Suzuki
    Nippon rinsho. Japanese journal of clinical medicine 12/2004; 62 Suppl 11:332-4.