Hajime Tsuji

Evaluation of New Japanese Diagnostic Criteria for Disseminated Intravascular Coagulation in Critically Ill Patients

New Japanese diagnostic criteria were prepared for disseminated intravascular coagulation (DIC) in critically ill patients and their usefulness was compared with the criteria of the International Society of Thrombosis and Haemostasis (ISTH) and those of the Japan Ministry of Health and Welfare (JMHW). In a retrospective study of patients with platelet counts of less than 150 × 103/mL, 52 cases (33.3%), 66 cases (42.3%), and 101 cases (64.7%) were diagnosed as DIC by the ISTH, JMHW, and new Japanese DIC criteria, respectively. The DIC state as diagnosed by the new Japanese DIC criteria included both DIC states as diagnosed by ISTH or JMHW criteria. Some DIC states diagnosed by the JMHW criteria included those diagnosed by ISHT criteria but this was not universal. The mortality of DIC as diagnosed by the ISTH or JMHW criteria was markedly high, compared to that for DIC diagnosed by the new Japanese criteria. The mortality of patients without DIC by ISTH was also high when they were diagnosed as DIC by the new Japanese criteria. The frequency of DIC by each set of diagnostic criteria was significantly higher in patients with infection than in those without infection. The mortality of DIC by each set of diagnostic criteria was significantly higher in patients with infection than in those without infection, and the mortality of overt-DIC by ISTH diagnostic criteria was also high in patients without infection.

Prevalence of genetic mutations in protein S, protein C and antithrombin genes in Japanese patients with deep vein thrombosis

INTRODUCTION Genetic deficiencies of PROS1, PROC, and SERPINC1 (antithrombin) are risk factors for deep vein thrombosis (DVT). Diagnosis of the inherited deficiencies of these three genes is sometimes difficult because of the phenotypic variability. This study was undertaken to reveal the frequency of nonsynonymous mutations of these three genes in Japanese DVT patients. PATIENTS/METHODS One hundred seventy-three DVT patients were registered by the Sub-group of Blood Coagulation Abnormality, from the Study Group of Research on Measures for Intractable Diseases. We sequenced the entire coding regions of the three genes in all DNA samples and identified the nonsynonymous mutations. RESULTS AND CONCLUSIONS For PROS1 we identified 15 nonsynonymous mutations in 28 DVT patients; for PROC, 10 nonsynonymous mutations in 17 patients; and for SERPINC1, 13 nonsynonymous mutations in 14 patients. Five patients had two mutations in PROS1 and PROC, and all of them had PROS1 K196E mutation. We previously identified one patient with a large PROS1 gene deletion. Thus, 55 out of 173 patients (32%) carried at least one genetic defect in the three genes. The PROS1 K196E mutation found in 15 Japanese DVT patients was the most prevalent. Mutations of PROC K193del and V339M were the second, each found in four patients. Our data suggested that the PROC K193del mutation caused the loss of the anticoagulant activity but not the amidolytic activity. Our effort is the first DNA resequencing study to identify the genetic variations in DVT patients without any consideration of their plasma activities and antigens. To minimize selection bias in a future evaluation of the contribution of genetic deficiency to DVT, we must recruit patients consecutively.

Effects of high-density lipoproteins on intracellular pH and proliferation of human vascular endothelial cells.

We investigated the effects of high-density lipoprotein (HDL) on the intracellular pH ([pH]i), and on the proliferation of human vascular endothelial cells (HUVEC), as well as on their production of prostacyclin (PGI2). The [pH]i was slightly acidified when extracellular Ca2+ was chelated with EGTA. Pretreatment of HUVEC with amiloride, the Na+/H+ exchange inhibitor, caused the [pH]i to become strongly acidic. The addition of HDL produced a biphasic shift in [pH]i, with a brief initial acidification followed by a rapid alkaline shift. The initial decrease in [pH]i was abolished in the cells pretreated with EGTA, and subsequent alkalinization was inhibited. The alkalinization of [pH]i disappeared in the cells pretreated with amiloride. These results suggest that [pH]i depends mainly on Na+/H+ exchange and partially on the extracellular Ca2+ of the HUVEC either in the resting unstimulated state or during HDL stimulation. In contrast, the addition of LDL produced an acidification of [pH]i, which was increased by LDL in the Ca(2+)-free condition. In the cells pretreated with amiloride, [pH]i was not further acidified by LDL. As a result, HDL promoted the proliferation of cells, an action that was inhibited by pretreatment with EGTA. However LDL inhibited cell proliferation, an action unaffected by EGTA pretreatment. The addition of HDL also enhanced the generation of prostacyclin in endothelial cells, the enhancement of PGI2 generation resulted from an increase in the release of Ca2+ from storage sites, due not only to an increased production of inositol 1,4,5-trisphosphate (IP3), but also to the alkalinization of [pH]i. These effects may be involved in the mechanism of HDLs anti-atherosclerotic action.

HMG CoA reductase inhibitor suppresses the expression of tissue factor and plasminogen activator inhibitor-1 induced by angiotensin II in cultured rat aortic endothelial cells

BACKGROUND It has been demonstrated that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (HRIs) reduce the incidence of acute cardiovascular events in patients with hyperlipidemia. Recent reports have shown that the protective effects of these drugs against cardiovascular events are also observed in patients without hyperlipidemia, but the mechanism of this favorable effect still remains unclear. In this study, the effects of HRIs on the endothelial regulation of thrombus formation were elucidated. METHODS AND RESULTS The mRNA and protein expression of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) induced by angiotensin II (Ang II) were evaluated in cultured rat aortic endothelial cells. Pretreatment with simvastatin (0.03-3 microg/ml) significantly inhibited TF and PAI-1 induction by Ang II in a dose- and time-dependent manner. These inhibitions were significantly attenuated by mevalonic acid or geranylgeranyl pyrophosphate. Both Rho inhibitor, C3 exoenzyme, and Rho kinase inhibitor, Y-27632, mimicked the inhibitory effects of simvastatin against TF and PAI-1 induced by Ang II. This result suggested that the Rho/Rho kinase pathway is related to the TF and PAI-1 induction by Ang II. CONCLUSION It was indicated that simvastatin maintains endothelial cells to be antithrombotic by inhibiting TF and PAI-1 expression via the Rho/Rho kinase pathways in which AngII induces TF and PAI-1 expression. These observations explain, at least partly, the mechanism of the favorable effects of simvastatin in reducing the thrombotic events.

Impact of recombinant soluble thrombomodulin (thrombomodulin alfa) on disseminated intravascular coagulation

INTRODUCTION We assessed the safety and effectiveness of recombinant soluble thrombomodulin (thrombomodulin alfa, TM-α) in the treatment of disseminated intravascular coagulation (DIC) in a post-marketing surveillance. METHODS The cases of 3548 patients with DIC caused by infection (n=2516, Infection-DIC) or hematological malignancy (n=1032, Hemat-DIC) were analyzed and compared to the results of a phase III (P-III) study. RESULTS The DIC scores were significantly decreased in the Infection-DIC and Hemat-DIC groups with TM-α treatment (both P<0.001). The incidences of critical bleeding adverse drug reactions (ADRs) in the Infection-DIC and Hemat-DIC groups were 2.6% and 2.4%, and the survival rates were 64.1% and 70.7%, respectively. Patients with DIC were subcategorized into three groups (Infection-DIC-1 or Hemat-DIC-1, P-III criteria-matched patients; Infection-DIC-2 or Hemat-DIC-2, P-III criteria-non-matched patients treated solely with TM-α; and Infection-DIC-3 or Hemat-DIC-3, P-III criteria-non-matched patients treated with TM-α and other concomitant anticoagulants). Subcategory analysis revealed that the incidences of critical bleeding ADRs of Hemat-DIC-2 and Hemat-DIC-3 were significantly higher and their survival rates were significantly lower than those of Hemat-DIC-1. By multivariate analysis in Hemat-DIC, younger age (odds ratio: 2.629, P=0.0033) and pre-existing bleeding (odds ratio: 2.044, P=0.019) were found to affect bleeding ADRs and the severity of underlying disease was the most important factor for survival rate (odds ratio: 0.288, P<0.001). CONCLUSIONS This surveillance provided real-world data for the safety and effectiveness of TM-α in the treatment of Infection-DIC and Hemat-DIC in general practice settings.

Antithrombin III deficiency in a patient with multifocal osteonecrosis.

The authors examined a 35-year-old man who had multifocal osteonecrosis on the right and left femoral heads, left humeral head, and right scaphoid. The patient previously had a diagnosis of Type I congenital antithrombin III deficiency but had no other risk factors for osteonecrosis. This patient was thought to have systemic thromboembolism because of the increased blood coagulability resulting from antithrombin III deficiency. Thrombophilia (increased likelihood of thrombosis) and hypofibrinolysis (reduced ability to lyse thrombi) have been implicated as causative factors for osteonecrosis. This case shows a possible relationship between thrombophilic antithrombin III deficiency and multifocal osteonecrosis.

Effect of inhibition of Na+-K+ ATPase on the prostacyclin generation of cultured human vascular endothelial cells.

Prostacyclin (PGI2) generation of cultured human vascular endothelial cells (VEC) was observed coincidentally with the increase of 45Ca net influx. Ca ionophore A23187 enhanced not only PGI2 generation and 45Ca net influx but also 45Ca efflux. PGI2 generation was completely abolished by the pretreatment with Ca++ immobilizer, TMB-8. A Na+-K+ ATPase inhibitor, ouabain increased 45Ca net influx, but decreased 45Ca efflux, and enhanced PGI2 generation. These observation indicate that PGI2 generation of VEC may be regulated by not only Ca++ but also Na+, and it was suggested that enhanced PGI2 generation by ouabain might be derived from the increased cytosolic Ca++concentration by the decreased Ca++ efflux, and it was considered to be originated from the suppression of Na+-Ca++ exchange systems by the increased intracellular Na+ concentration via inhibition of Na+-K+ ATPase activity by ouabain. Enhancement of PGI2 generation of VEC by the increased ouabain like substances (OLS) in hypertension is suspected to be beneficial on the maintenance of vascular homeostasis.

A large deletion of the PROS1 gene in a deep vein thrombosis patient with protein S deficiency.

Inherited deficiency of protein S encoded by the PROS1 gene constitutes an important risk factor for deep vein thrombosis (DVT). Nevertheless, although more than 200 deleterious genetic variations in PROS1 have been identified, causative point mutations of PROS1 gene are not detected in approximately half of protein S-deficient families. The present study investigated whether there may exist a large deletion in PROS1 that constitutes a genetic risk factor for Japanese DVT patients. A multiplex ligation-dependent probe amplification analysis was employed to identify the deletions in PROS1 in 163 Japanese patients with DVT. A large gene deletion was identified in one patient who showed 16% protein S activity and did not carry point mutations in PROS1 by DNA sequencing and it was validated by the quantitative PCR method. The deletion spanned at least the whole PROS1 gene (107 kb) and at most from the centromere located downstream of PROS1, to before the D3S3619 marker, the first heterozygous marker in the upstream of PROS1 in chromosome 3. In conclusion, a large deletion in PROS1 was shown to partly account for DVT with protein S deficiency. Screening for large deletions in PROS1 might be warranted in PROS1 causative point mutation-negative DVT patients with protein S deficiency.

Adrenomedullin Inhibits Angiotensin II–Induced Expression of Tissue Factor and Plasminogen Activator Inhibitor-1 in Cultured Rat Aortic Endothelial Cells

Abstract—Adrenomedullin (AM) is a potent vasodilating peptide having a variety of pharmacological properties mainly in respect to vascular pathophysiology. We have previously demonstrated that angiotensin II (Ang II) or natriuretic peptides have influence on the expression of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1) in vascular endothelial cells. The aim of this study was to elucidate the effects of AM on TF and PAI-1 mRNA and protein expression in endothelial cells. As a result, AM inhibited Ang II-induced TF and PAI-1 mRNA expression in a dose- and time-dependent manner. Because the expression of TF and PAI-1 mRNA induced by Ang II was attenuated by the increase of intracellular concentrations of cAMP by forskolin and 8-bromo-cAMP and because AM increased the intracellular level of cAMP in rat aortic endothelial cells, it was indicated that the inhibitory effect of AM on the expressions of TF and PAI-1 was mainly mediated by the cAMP-dependent signal transduction. Furthermore, the inhibitory effect of AM on TF and PAI-1 expression was partly attenuated by an NO synthase inhibitor, NG-nitro-l-arginine methyl ester. In conclusion, AM is shown to contribute to the regulation of blood coagulation and fibrinolysis by vascular endothelial cells mainly via the cAMP pathway.

Effects of Bradykinin on Prostaglandin I2 Synthesis in Human Vascular Endothelial Cells

The effects of bradykinin on the regulatory mechanisms of prostacyclin synthesis in endothelial cells were investigated in association with intracellular Ca(2+) kinetics, cytosolic phospholipase A(2) (cPLA(2)) activity, and mRNA expression of cPLA(2) and prostaglandin H synthase (PGHS) isoforms. Bradykinin enhanced prostacyclin release from endothelial cells time-dependently, but pretreatment with EGTA H-7 or HOE 140 inhibited bradykinin-induced prostacyclin release. Bradykinin increased both the influx of extracellular Ca(2+) and Ca(2+) release from the intracellular Ca(2+) storage sites. These reactions occurred within 5 minutes after bradykinin stimulation. Within 15 minutes, bradykinin activated cPLA(2) to 1.3-fold the control level. The constitutive expressions of mRNA of cPLA(2), PGHS-1, and PGHS-2 was 87, 562, and 47 amol/microg RNA, respectively. With the stimulation of bradykinin, cPLA(2) mRNA increased to 746 amol/microg RNA in 15 minutes, PGHS-1 mRNA increased to 10 608 amol/microg RNA, and PGHS-2 mRNA increased to 22 400 amol/microg RNA in 180 minutes. Pretreatment with cycloheximide superinduced cPLA(2) and PGHS-2 mRNA expression but almost completely inhibited PGHS-1. Pretreatment with EGTA had effects similar to pretreatment with cycloheximide in the case of cPLA(2) and PGHS-1 but did not affect PGHS-2. These findings suggest that the elevation of cPLA(2) activity caused by the increase of intracellular Ca(2+) concentration is important in the early phase of bradykinin-induced prostacyclin synthesis and that the mechanisms regulating cPLA(2) are different from those regulating PGHS isoforms in endothelial cells.