Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P00750 (PLA)
 16,800 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

When fibrin deposition and removal are properly balanced, the organism is protected from both a catastrophic loss of blood at the site of injury and the inappropriate loss of fluidity within the vascular system. When these activities are not properly balanced, however, severe bleeding or thromboses can occur. Myocardial infarction is a common and morbid consequence of the latter. The thrombin/thrombomodulin complex plays an essential role in regulating this balance because it generates both an anticoagulant substance, activated protein C, and an antifibrinolytic substance, activated TAFI (thrombin activatable fibrinolysis inhibitor, also known as plasma carboxypeptidase B or carboxypeptidase U). Thus, the coagulation and fibrinolytic cascades are explicitly linked by virtue of thrombin catalyzed activation of TAFI, either by the thrombin/thrombomodulin complex or, in the absence of thrombomodulin, by the massive amounts of thrombin generated through the factor XI-dependent pathway after clotting. Some potential targets for diagnosis, prognosis and therapy related to the balance between fibrin formation and removal include: development of a convenient global assay for plasma fibrinolytic potential; an assay for plasma or urine thrombomodulin that had been oxidized at methionine 388 and thereby has lost its capacity to stimulate activation of protein C but not TAFI; an assay for activated TAFI; discovery of a means for tapping the tremendous potential of the vasculature to acutely release tissue-type plasminogen activator; and an assessment of the potential role of polymorphisms in the TAFI gene which might influence TAFI levels or the properties TAFIa. In addition, a much fuller and quantitative understanding of the properties of the coagulation and tibrinolytic cascades is needed in order to optimize diagnosis, prognosis and therapy in disorders such as myocardial infarction that are related to the balance between fibrin formation and removal.
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PMID:Myocardial infarction and the balance between fibrin deposition and removal. 1166 89

This study compared iloprost and nifedipine to ascertain whether they could improve parameters of endothelial and platelet functions in the treatment of Raynaud's phenomenon secondary to systemic sclerosis. Thirteen patients affected by systemic sclerosis were treated with intravenous infusion of iloprost, and 7 patients were treated with oral nifedipine. Blood samples were taken at baseline and after 6 and 12 months of therapy to assess main serological indexes of endothelial damage, thrombin activation, fibrinolysis, as well as natural inhibitors of coagulation. After 12 months of therapy, the patients treated with iloprost had a significant decrease in thrombomodulin levels (p = 0.02) and a significant increase in tissue-plasminogen activator levels (p = 0.007), in comparison with the patients taking nifedipine (p = 0.007). Moreover, patients treated with nifedipine showed increased levels of thrombin-antithrombin complex after 12 months of therapy in comparison with baseline values (p = 0.03) and in comparison with the values of the patients treated with iloprost over the same period (p = 0.05). These preliminary results thus seem to indicate that iloprost plays an important, if at least partial, role in the protection and restoration of endothelial integrity in patients with systemic sclerosis.
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PMID:Coagulative modifications in patients with systemic sclerosis treated with iloprost or nifedipine. 1169 6

Blackfoot disease (BFD) is an endemic peripheral vascular occlusive disease that occurred in the southwest coast of Taiwan. It is believed that arsenic in the drinking water from artesian wells plays an important role in the development of the disease. We have previously shown that BFD patients had significant lower tissue-type plasminogen activator (t-PA) antigen level and higher plasminogen activator inhibitor, Type 1 (PAI-1) antigen level than normal controls. The purpose of this study was to investigate the effects of arsenite on the fibrinolytic and anticoagulant activities of cultured macrovascular and microvascular endothelial cells. Incubation of human microvascular endothelial cells (HMEC-1), but not human umbilical vein endothelial cells (HUVECs), with arsenite caused a decrease of t-PA mRNA level, a rise of both PAI-1 mRNA level and PAI activity. Arsenite could also inhibit the thrombomodulin (TM) mRNA expression and reduce the TM antigen level in HMEC-1. In conclusion, arsenite had a greater effect on HMEC-1 as compared to HUVECs in lowering the fibrinolytic activity and may be responsible for the reduced capacity of fibrinolysis associated with BFD.
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PMID:Decrease of fibrinolytic activity in human endothelial cells by arsenite. 1186 8

We evaluated the effects of surgical invasion and vascular injury on hemostatic abnormalities in seventeen ASA I-II patients undergoing prolonged surgeries of eight hours or more consisting of tumor excision, radical neck dissection and free flap reconstruction in the maxillofacial region. As molecular markers of blood coagulation and surgical invasion, prothrombin fragment 1 + 2 (F 1 + 2), interleukin-6 (IL-6), tissue-type plasminogen activator (tPA), thrombomodulin (TM) and plasmin alpha 2-plasmin inhibitor complex (PIC) were measured during surgery and on the first and second postoperative days. The F 1 + 2 values increased significantly during surgery and decreased postoperatively, and reached the maximum at the end of surgery. Changes in IL-6 and tPA were similar to those of F 1 + 2, and there was a correlation in the levels of F 1 + 2 and IL-6 (r = 0.54), tPA (0.41) and PIC (0.30) at each measurement time. PIC and TM, however, did not show statistically significant changes intra- and postoperatively, nor was there any correlation between F 1 + 2 and TM values. From these results, we conclude that inflammatory mediators and endothelial stimulation activated by surgical invasion may influence hypercoagulability. Vascular injury, however, did not act as the main coagulation factor during prolonged maxillofacial surgery.
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PMID:[Effects of vascular injuries on hemostatic abnormalities in prolonged surgeries of maxillofacial malignant cancer]. 1199 46

Hemostatic abnormalities in 26 patients following bone marrow transplantation (BMT) were examined. In the event-free survival group, the plasma levels of antithrombin (AT) and protein C (PC) were significantly decreased 1 and 2 weeks after BMT, and the plasma levels of thrombomodulin (TM) and tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPA-PAI-I complex) were significantly increased from 4 weeks to 13 weeks after BMT. Excepting AT, there was no significant difference in hemostatic parameters before BMT among the event-free survival, 6-month survival, and death within 6 months groups. On day 0 following BMT, only plasma AT levels were significantly lower in the 6-month survival group than in the death within 6 months group. From 1 to 3 weeks after BMT, plasma levels of AT or PC were significantly lower in the death within 6 months group than in the 6-month survival group. From 1 to 5 weeks after BMT, the plasma levels of TM and tissue type plasminogen activator-plasminogen activator inhibitor-I complex (tPA-PAI-I complex) were significantly higher in the 6-month survival group than in the death within 6 months group. From 1 to 13 weeks after BMT, the plasma levels of D-dimer or soluble fibrin monomer (SFM) were significantly higher in the death within 6 months group than in the 6-month survival group. There was no remarkable difference in plasma levels of thrombin-antithrombin comlex or plasmin-plasmin inhibitor complex following BMT between these groups of patients. These findings suggest that the decrease in the plasma AT or PC level reflects early occurrence of complications of prognostic significance and that the increase in vascular endothelial cell markers such as plasma levels of TM or tPA-PAI-I complex reflects occurrence of complications during the middle course of BMT. Plasma levels of D-dimer and SFM may be useful markers for predicting complications associated with poor prognosis after BMT.
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PMID:Hemostatic abnormalities following bone marrow transplantation. 1212 Oct 52

Several studies have shown that patients with venous thrombosis have elevated levels of factor VIII (FVIII) at an increased frequency. Most such patients also have high von Willebrand factor (vWF) levels. Since vWF is synthesized by the vascular endothelium, we hypothesized that elevated FVIII levels would also be associated with an increase of other endothelial cell-derived coagulation proteins suggesting perturbation of the endothelium. In 100 healthy individuals and 129 patients with venous thromboembolism, we have determined antigenic FVIII levels along with several endothelial proteins including vWF, soluble thrombomodulin (sTM), tissue-type plasminogen activator (t-PA), and plasminogen activator inhibitor 1 (PAI-1). Levels of FVIII, vWF, PAI-1 and t-PA were significantly increased in patients compared with the controls (FVIII, vWF, and PAI-1,P < 0.001; t-PA, P < 0.05). Levels of sTM, however, were higher in the controls than in the patients (P < 0.001). Whereas the FVIII levels correlated well with the vWF levels in the patients (correlation, 0.61; P < 0.001) and the controls (correlation, 0.70; P < 0.001), there was neither a relevant correlation between FVIII and sTM, PAI-1, and t-PA, nor between vWF and sTM, PAI-1, and t-PA in the patients and the controls. In conclusion, although levels of PAI-1 and t-PA can be found, on average, at increased levels in patients with thrombosis, FVIII levels correlate only with vWF but not other endothelial cell-derived coagulation and fibrinolysis proteins including sTM, PAI-1, and t-PA.
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PMID:In patients with deep-vein thrombosis elevated levels of factor VIII correlate only with von Willebrand factor but not other endothelial cell-derived coagulation and fibrinolysis proteins. 1243 42

To determine the role of CD14 in lipopolysaccharide (LPS)-induced effects on coagulation and fibrinolysis in humans, 16 healthy subjects received an intravenous injection of LPS preceded by intravenous IC14, a recombinant chimeric monoclonal antibody against human CD14, or placebo. LPS-induced coagulation activation (tissue-factor mRNA in whole blood cells and plasma concentrations of F1+2) was not influenced by IC14, whereas the antibody reduced the increase in thrombin-antithrombin complexes and soluble fibrin. LPS injection also was associated with an early activation of fibrinolysis (plasma concentrations of tissue-type plasminogen activator and plasmin-alpha(2)-antiplasmin complexes), followed by an inhibitory response (plasminogen activator inhibitor type 1), which were attenuated by IC14. Furthermore, LPS reduced thrombin-activatable fibrinolysis-inhibitor antigen levels and increased soluble thrombomodulin levels, which were not influenced by IC14. These results suggest that different hemostatic responses during endotoxemia may proceed via CD14-dependent and -independent pathways.
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PMID:Effects of IC14, an anti-CD14 antibody, on coagulation and fibrinolysis during low-grade endotoxemia in humans. 1250 46

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.
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PMID:High plasma fibrinogen level is associated with poor clinical outcome in DIC patients. 1250 60

Altered endothelial anti-thrombotic properties have been observed in primary and secondary pulmonary hypertension. In the Eisenmenger syndrome, correlations of these abnormalities with the clinical status and occurrence of chronic intravascular coagulation (CIC) have not been confirmed. The purpose of this study was to investigate whether the occurrence of CIC, as determined by circulating levels of D-dimer is associated with changes in endothelial markers in Eisenmenger patients; and to identify variables that correlate with the severity of clinical presentation. Twenty-one patients were enrolled (ages, 4-52 years). Plasma levels of D-dimer, tissue plasminogen activator (t-PA), thrombomodulin, and von Willebrand factor antigen (vWF:Ag) were measured with enzyme-linked immunosorbent assay. Univariate and multivariate analyses were used to differentiate patients with stable (group 1, N=12) from those with unstable disease (group 2, N=9). Increased t-PA (p<0.0001) and vWF:Ag (p=0.001) and decreased thrombomodulin (p<0.0001) were associated with increased D-dimer levels (p=0.0201) in patients. Group 2 had a higher prevalence of affected women (p=0.0242), lower arterial oxygen saturation, and higher t-PA levels compared with group 1 (p<0.0001, discriminant analysis). t-PA and vWF:Ag correlated positively in group 2 (r=0.71, p=0.0309), but not in group 1 (r=0.25, p=NS). Two patients in group 2 but none in group 1 had episodes of pulmonary arterial thrombosis. Endothelial dysfunction is associated with evidence of CIC and correlates to some extent with the severity of symptoms in these patients.
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PMID:Endothelial dysfunction associated with chronic intravascular coagulation in secondary pulmonary hypertension. 1251 85

The placenta is a highly vascularized organ functioning as the interface between fetal blood, which is confined within the villous blood vessels, and maternal blood, which flows in decidual arteries and washes the intervillous spaces in contact with syncytiotrophoblast (STB) cells. The STB adopts vascular characteristics such as the presence of von Willebrand factor (vWF), CD31 markers, adhesion molecules, and coagulation components. The special structure of the placenta requires efficient mechanisms for fast activation and localized regulation of coagulation. The presence of procoagulant and anticoagulant components on placental vascular endothelial cells (EC) and STB is essential for hemostasis. Activation of coagulation may be a favored process, as suggested by elevated fibrin depositions documented in some pathologic states. Increased localized procoagulant components such as tissue factor (TF) and plasminogen activator inhibitors (PAI-1, PAI-2), are associated with some pregnancy complications. Several anticoagulants regulate placental coagulation: tissue factor pathway inhibitor (TFPI) is primarily produced in EC; TFPI-2, a variant of TFPI, has been purified from the placenta and was identified in the STB lining the villi; thrombomodulin, a membrane glycoprotein that activates protein C, is localized in EC and apical membranes of STB; annexin V, an anticoagulant that binds to negative membrane phospholipids, is abundant on normal placental STB, whereas reduced STB annexin V was associated with the presence of antiphospholipid antibodies. The placenta is a putative source of coagulation components. However, the interplay between local procoagulant and anticoagulant mechanisms and their association with pregnancy complications need to be assessed.
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PMID:Procoagulant and anticoagulant mechanisms in human placenta. 1270 21


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