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Yoshitaka Mori

Publications and source records attributed to Yoshitaka Mori.

11 recordsLinked to original sources
PubMed2006

Decreased ADAMTS13 activity in plasma from patients with thrombotic thrombocytopenic purpura.

The ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type I domain 13) activity was measured by a fluorescence resonance energy transfer (FRET) assay in the plasma of healthy volunteers and thrombotic thrombocytopenic purpura (TTP) patients to examine its usefulness in the diagnosis of TTP. The plasma levels of the ADAMTS13 activity did not show a normal distribution. Its median value was 107% (range: 55-170%) in healthy volunteers, but was significantly lower in patients with TTP (acquired or familial) and in patients with hematopoietic stem cell transplantation. However, it was not significantly lower in patients with antiphospholipid syndrome (APS). The ADAMTS13 activity by a FRET assay was closely correlated with that by the ADAMTS13 multimer method (r=0.816; p<0.001). In 18 patients with less than 10% of ADAMTS13 activity by FRET assay, less than 10% of that by multimer assay was 16, thus suggesting a good correlation for a low level of ADAMTS13. These findings suggest that the ADAMTS13 FRET assay correlates well with the ADAMTS13 multimer method and it is therefore useful for making a diagnosis of TTP.

ADAM Proteins↗
PubMed2005

Prognostic impact of aortic calcification index and ankle-arm blood pressure index in patients under hemodialysis.

The mortality rate is high in patients receiving hemodialysis (HD), atherosclerotic diseases being the major cause of death. As marker of clinical outcome, a prospective examination of atherosclerotic tests and atherosclerotic risk factors in patients receiving HD was performed. On April 2000, 84 patients receiving HD were followed up until April 2002. At entry to the study, several atherosclerotic tests, including ankle-arm blood pressure index (API), aortic calcification index (ACI), and atherosclerotic risk factors, were performed. In 36 patients with old thrombotic events, 26 had new thrombotic events. Of 48 patients without previous thrombotic events, 15 had new thrombotic events. During 2 years, 41 patients had new thrombotic events and 15 patients died due to thrombotic disorders. The HD durations were significantly longer in non-survivors than survivors and the body mass index was lower in non-survivors than survivors. There was a significant difference in the values of ACI and API between survivors and non-survivors, and between patients with and without thrombotic events. These findings suggest that the ACI and API have a prognostic value because they might predict the occurrence of thrombosis.

Adult↗
PubMed2004

[Changes of ADAMTS13 activity and endothelial cell markers in TMA cases].

Severe deficiency of ADAMTS13 activity was recently found in patients with thrombotic thrombocytopenic purpura (TTP). The great advance associated with these basic and clinical studies on ADAMTS13 is the possible elucidation of the pathogenesis of TMA (thrombotic microangiopathy). However, the exact pathogenetic mechanism in TMA without severe deficiency of ADAMTS13 activity remains unknown due to heterogeneity of the disease. In this study, there were 7 patients with TTP, 7 with HUS, 3 with drug-induced HUS, 1 with VOD, and 1 with IVL out of 19 TMA patients with a moderate deficiency (6-70%) of ADAMTS13 activity. Five of the 7 TTP patients had a poor outcome. Plasma thrombomodulin and t-PA-PAI-1 complex levels in TMA patients with a moderate deficiency of ADAMTS13 activity were significantly higher than those in patients with a severe deficiency of ADAMTS13 activity. These data suggest that the etiology in these patients may be systemic vascular endothelial cell damage.

ADAM Proteins↗
PubMed2003

High plasma fibrinogen level is associated with poor clinical outcome in DIC patients.

We measured the plasma level of fibrinogen in 560 patients with disseminated intravascular coagulation (DIC) and evaluated its relationship with outcome and with other hemostatic markers. Forty-seven percent of patients had >200 mg/dL of plasma fibrinogen and 24% had <100 mg/dl of plasma fibrinogen, suggesting that plasma fibrinogen level is not a sensitive marker for DIC. In our analysis of outcome and plasma fibrinogen levels, the rate of death was high in leukemia/lymphoma patients with high fibrinogen concentration, but no significant difference in outcome was observed in relation to plasma fibrinogen concentration in non-leukemia/lymphoma patients with DIC. Among patients with leukemia/lymphoma, the frequency of organ failure was markedly high in patients with high plasma levels of fibrinogen. Among patients without leukemia/lymphoma, the frequency of organ failure increased concomitantly with the increase in plasma fibrinogen levels. The international normalized ratio was significantly increased in leukemia/lymphoma patients with low fibrinogen. FDP levels were slightly increased in patients with low fibrinogen. Platelet count was significantly low in patients without leukemia/lymphoma with high fibrinogen. DIC score increased concomitantly with the reduction in plasma fibrinogen levels. Plasma levels of thrombomodulin and tissue factor were significantly high in patients with high fibrinogen levels. Plasma levels of antiplasmin and plasminogen were significantly decreased in patients with low fibrinogen. Plasma levels of plasmin plasmin-inhibitor complex and tissue type plasminogen activator/plasminogen activator inhibitor-1 complex (PAI-I) were significantly higher in patients with low fibrinogen than in those with high fibrinogen. Plasma levels of PAI-I and IL-6 were significantly higher in patients with high fibrinogen than in those with low fibrinogen. Patients with high fibrinogen levels showed less activation of secondary fibrinolysis, which might explain the occurrence of organ failure and poor outcome.

Adult↗
PubMed2003

Atherosclerotic and hemostatic abnormalities in patients undergoing hemodialysis.

Vascular events caused by atherosclerosis are the major cause of death in patients undergoing hemodialysis (HD). The relationship between the tests of atherosclerosis and hemostasis in 84 patients with HD was examined. Abnormal test results indicting the occurrence of atherosclerosis were found in 66% by the Fontaine score, in 33% by ankle blood pressures, and in 79% by aortic calcification index (ACI). When HD was prolonged, the mean Fontaine score and ACI were further increased. Particularly, the ACI tended to correlate with HD duration. The ankle-brachial index (ABI) was decreased in patients with HD duration of more than 10 years. Before HD, the plasma levels of fibrinogen, plasmin-plasmin inhibitor complex (PIC), thrombomodulin (TM), and D-dimer were increased, while the plasma levels of protein C (PC), antithrombin (AT), thrombin-antithrombin complex (TAT), and tissue plasminogen activator (tPA)-plasminogen activator inhibitor-I (PAI-I) complex (tPA-PAI-1 complex) were decreased. With prolonged HD, the plasma levels of AT and PC were decreased, while those of D-dimer were increased. The plasma levels of TAT and TPA-PAI-1 complex were significantly increased and those of PIC, soluble fibrin (SF) and D-dimer tended to be high in patients with less than 0.7 of ABI. The plasma levels of D-dimer, TPA-PAI-1 complex, TAT, PIC, and SF tended to be high in patients with more than 0.5 in ABI. These findings suggest that patients undergoing HD have progressive atherosclerosis and that this is associated with some hemostatic abnormalities.

Aged↗
PubMed2003

Good or poor responses of hemostatic molecular markers in patients with hematopoietic disorders after treatment of disseminated intravascular coagulation.

Changes of hemostatic markers in 226 patients with disseminated intravascular coagulation (DIC) and hematopoietic disorders were examined after treatment of DIC. The changes in prothrombin time (PT) ratio, fibrinogen, fibrin and fibrinogen degradation products (FDP), antithrombin, and protein C, thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), and soluble fibrin monomer complex (SFMC) in all patients with DIC were significant during the clinical course of DIC, but those of D-dimer, thrombomodulin (TM), tissue factor (TF), and tissue factor pathway inhibitor (TFPI) were not. Activated partial thromboplastin time (aPTT) and PT were significantly longer in the poor response group than in good response group. Plasma levels of FDP, TAT, PPIC, SFMC, TM, and DIC score were significantly higher in poor response group than in good response. Protein C and antithrombin levels were significantly lower in poor response group than in good response group. The changes of PT ratio, fibrinogen, FDP, DIC score, antithrombin, plasmin inhibitor, and protein C were significant in the good response group, but these levels were not significant in the poor response group. The changes in plasma TAT and SFMC levels were significant in the good response group but were not in poor response group. The changes in D-dimer, TM, TF, or TFPI were not significant in both groups. These findings suggest that anticoagulant agents should be administered at levels below TAT 40 ng/mL or SFMC 300 microgram/mL in patients with DIC and hematopoietic disorders.

Antithrombins↗
PubMed2003

Effects of lipid abnormalities on arteriosclerosis and hemostatic markers in patients under hemodialysis.

Vascular events caused by arteriosclerosis are the major cause of death in patients under hemodialysis (HD). Arteriosclerosis is associated with lipoprotein abnormalities such as increased serum levels of low-density lipoprotein (LDL), especially of modified LDL (M-LDL) and oxidized LDL (Ox-LDL). We examined the relationship between markers of arteriosclerosis, hemostasis, and lipid metabolism in patients with chronic renal failure, hyperlipidemia, and healthy volunteers. In patients under HD, the serum levels of total cholesterol, LDL, and triglyceride (TG) were decreased, but the serum levels of M-LDL were increased compared to HL and healthy volunteers. In patients with CRF, the serum levels of Ox-LDL in patients under HD were lower than in those under continuous ambulatory peritoneal dialysis or conservative therapy. The plasma levels of antithrombin and protein C were significantly lower and the plasma levels of thrombomodulin were significantly higher in patients under HD compared to those under conservative therapy. These data show that patients under HD were more in hypercoagulable state than those under conservative therapy. Among patients under HD, only the plasma levels of von Willebrand factor were significantly increased in patients with more than 30 U/L of Ox-LDL compared to those with less than 30 U/L of Ox-LDL. There was no significant difference in the tests of arteriosclerosis among M-LDL values and Ox-LDL values. These findings suggest that abnormalities of lipid are not the main risk factor for arteriosclerosis disease in patients under HD.

Aged↗
PubMed2003

Increased soluble fibrin in plasma of patients with disseminated intravascular coagulation.

Plasma levels of soluble fibrin (SF) were measured in 1184 patients with disseminated intravascular coagulation (DIC) according to Japanese Ministry of Health and Welfare (JMHW) criteria. The usefulness of SF for the diagnosis of DIC was compared with other hemostatic molecular markers. Most hemostatic markers were significantly increased in patients with DIC than in those without DIC. Plasma levels of fibrin and fibrinogen degradation products, thrombin-antihtrombin complex, plasmin-plasmin inhibitor complex, D-dimer, thrombomodulin, and SF levels were also significantly higher in those with pre-DIC than in those without DIC. In classification of overt DIC by International Society of Thrombosis and Haemostasis (ISTH) criteria, most hemostatic markers were significantly increased in patients with overt DIC than in those without overt DIC. Plasma levels of SF 'in patients with DIC were significantly higher than those in patients with pre-DIC, which were significantly higher than in those without DIC. Plasma levels of SF were also significantly higher in patients with overt DIC than in those with non-overt DIC. The correlation between plasma SF levels and DIC score according to JMHW criteria or ISTH criteria was good. Receiver operating characteristic analysis shows that SF was the best marker for the diagnosis of DIC or overt DIC. These findings suggest that plasma SF might be useful marker for the diagnosis of DIC or overt DIC.

Biomarkers↗
PubMed2002

Predicting response to plasma exchange in patients with thrombotic thrombocytopenic purpura with measurement of vWF-cleaving protease activity.

BACKGROUND: Severe deficiency of vWF-cleaving protease (vWF-CPase) activity was recently found in patients with thrombotic thrombocytopenic purpura (TTP). Although the survival of patients with TTP has been dramatically improved with plasma exchange (PE), there are still many patients who are refractory to PE and immunosuppressive therapy. STUDY DESIGN AND METHODS: The activities of vWF-CPase and its inhibitor were measured in 27 patients with nonfamilial TTP and hemolytic-uremic syndrome (HUS) to examine the relationship between the clinical variables and vWF-CPase activity. RESULTS: Eight of nine patients with HUS had more than 40 percent of vWF-CPase activity, whereas one had 28 percent of the normal level at the acute phase. Ten of 12 TTP patients with a good outcome had a severe deficiency of vWF-CPase activity and its inhibitor, whereas four of six patients with a poor outcome had a moderate deficiency of vWF-CPase activity along with a lack of the inhibitor. PE produced normalization of the vWF-CPase activity and neutralization of the inhibitor in TTP patients with a good outcome; however, some TTP patients with vWF-CPase inhibitor had relapsed and required an immunosuppressive therapy. The response to the combination therapy with PE and immunosuppressive treatment was poor in TTP patients without a severe deficiency of vWF-CPase activity. CONCLUSION: Assays of vWF-CPase activity and its inhibitor may be useful for predicting the response to therapy and the outcome of patients with TTP. In some patients, nonfamilial TTP with a poor prognosis may not be caused by a constitutional or acquired deficiency of vWF-CPase with its inhibitor. Although PE and immunosuppressive therapy are effective in patients with nonfamilial TTP and a vWF-CPase inhibitor, other therapeutic modalities may be needed for nonfamilial TTP with unknown etiology.

ADAM Proteins↗