Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.21.69 (APC)
 16,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To determine whether children treated with chronic peritoneal dialysis have a hypercoagulable state, various coagulation and fibrinolytic factor concentrations or activities were measured in 17 children undergoing chronic peritoneal dialysis. The patients had significantly increased activities of factors VII and VIII, and increased concentrations of von Willebrand factor (vWF), fibrinogen, factor XIIIA and factor XIIIS compared to reference values (P less than 0.001 in each case). The activated partial thromboplastin time was prolonged (P less than 0.001) and the thrombin clotting time was decreased (P less than 0.05) in these children. The prothrombin time and activities of factors XII, XI, IX, X, V and II were not significantly different from control values. Protein C concentrations were similar to normal, but antithrombin III concentrations were increased (P less than 0.05). Within the fibrinolytic pathway, decreased concentrations of plasminogen were found (P less than 0.001) and the concentrations of alpha-2-antiplasmin were increased (P less than 0.001). The plasma albumin concentration was below 33 g/l in 13 of the 17 children. The duration of treatment with peritoneal dialysis was directly correlated with vWF concentrations (P less than 0.001) and inversely correlated with factor VII concentrations (P less than 0.01). Of these patients 2 have since had clinical thrombotic episodes. The coagulation abnormalities found may have a role in the occurrence of thrombosis complicating renal transplantation.
 ...
PMID:Coagulation abnormalities in chronic peritoneal dialysis. 239 81

The protein C activator Protac from A. contortrix venom is being investigated as a potential antithrombotic agent and as a tool for the preparation of activated protein C. Its established major application is the zymogen activation in functional protein C determinations based on either a clotting assay or a chromogenic substrate technique. The sensitivity of the activated partial thromboplastin time as an indicator reaction for Protac activated protein C depends on the contact activator component of the reagent. Protein C dose-response increased in the following order: kaolin greater than ellagic acid greater than sulfatide. This phenomenon is due to a competition of molecular affinities between Protac, plasma components and the different activating surfaces.
 ...
PMID:Practical application of the protein C activator Protac from Agkistrodon contortrix venom. 246 12

Lupus-like anticoagulants (LLA), lupus anticoagulant and/or anticardiolipin antibody, are increasingly recognized in association with venous and arterial thrombotic events. We recently reviewed our experience with patients undergoing revascularization for lower-limb ischemia who were found to have LLA. Nine patients had LLA based on a prolongation of the partial thromboplastin time or by anticardiolipin assay by an enzyme-linked immunosorbent assay system. The ages of the patients ranged from 23 to 57 years. There were seven (78%) men, six (67%) blacks, two (22%) diabetic patients, and three (33%) hypertensive patients. One patient had systemic lupus erythematosus. All patients except one were cigarette smokers. Four patients had concurrent regulatory protein abnormalities: three protein C deficiencies, one protein S deficiency, and one plasminogen deficiency. The nine patients had 10 lower-extremity arterial reconstructions with two postoperative failures within 30 days. Patients were anticoagulated with heparin or aspirin after all but one operation. Patients at risk were identified on the basis of age (less than 51 years), unexplained early graft thrombosis, or history of venous or arterial thrombotic events. This group of patients is believed to be at risk for early postoperative thrombosis. Postoperative anticoagulation after revascularization for patients with LLA may be beneficial.
 ...
PMID:Lupus-like anticoagulants and lower extremity arterial occlusive disease. 250 7

We have evaluated the quantitative relationship between lipopolysaccharide (LPS, endotoxin), fibrinopeptide A (FPA), antithrombin (AT), protein C (PC) and extrinsic pathway inhibitor (EPI) in plasma from 39 consecutively admitted patients with systemic meningococcal disease (SMD). The most severely ill patients with fulminant meningococcal septicemia (n = 13, 6 dead) had significantly (p less than 0.01) higher plasma levels of LPS and FPA and lower levels of PC and AT on admission as compared with the less severe clinical presentations (n = 26, 1 dead). The levels of EPI on admission were significantly (p less than 0.05) higher in nonsurvivors vs survivors with fulminant septicemia. As the disease progressed, the levels of LPS, FPA, AT and PC declined, while the levels of EPI increased. Three of six nonsurviving septicemic patients had levels of EPI greater than 200% within 16 hours of admission vs two of 30 survivors (p = 0.02). The results suggest that increasing levels of LPS in SMD elicit increasing consumption coagulopathy, contributing to the organ pathophysiology. The kinetics of EPI, inhibiting the thromboplastin-FVIIa-FXa complex, differs markedly from the kinetics of AT and PC i.e. increases as opposed to decreases.
 ...
PMID:The quantitative association of plasma endotoxin, antithrombin, protein C, extrinsic pathway inhibitor and fibrinopeptide A in systemic meningococcal disease. 251 Mar 54

Serial determinations of beta-thromboglobulin (BTG), platelet factor 4 (PF4), fibrinopeptide A (FPA), antithrombin III (ATIII), protein C (PC), fibrin (ogen) degradation product (FDP), FDP D-dimer, activated partial thromboplastin time (APTT), prothrombin time (PT), and euglobulin lysis time (ELT) were performed in 18 patients with non-progressing stroke and 14 patients with progressing stroke in order to predict the development of progressing stroke. Increasing levels of BTG, PF4 and FDP with frequent fluctuation were noted in both kinds of stroke. Fluctuation of FPA levels was also noted but was less pronounced. PC levels were found to be slightly decreased with fluctuation but the mean was still in the lower normal limit. BTG, PF4 and PC all elevated at the time of deterioration of physical condition in patients with progressing stroke, whereas FPA had no definite change at that time. From our study, we conclude that both platelet activation and coagulation process do occur in both kinds of stroke. But the latter plays a minor role in the formation of thrombosis. The hemostasis change, especially concerning the thrombosis formation, probably plays a role in the development of progressing stroke, but we cannot predict their development even by the detections of the newly known molecular substances appearing in various steps of the hemostatic mechanism. Development of new tests for understanding the whole dynamic change of the thrombosis process is necessary for accurate prediction of the progressing stroke in the future.
 ...
PMID:The serial hemostasis-related changes in patients with cerebral infarction: comparison between progressing and non-progressing stroke. 253 1

Combined deficiency of factor V and factor VIII, a rare bleeding disorder, was found in a 43 year-old male. He had often presented manifestations of easy bruising since childhood, but none of his family had shown evidence of a bleeding tendency. We examined him and his family as far as we could and his abnormality of blood coagulation was apparent, but the members of his family were normal. The prothrombin time and activated partial thromboplastin time of this patient were prolonged, but his thrombin time was normal. Factor V and factor VIII coagulant activity were low, but von Willebrand factor antigen and activity (ristocetin cofactor activity) levels were normal. Protein C and Protein C inhibitor antigen and activity levels were also found to be normal. Following 1-deamino-8-D-arginine vasopressin (DDAVP) injection, he had immediate increases in factor VIII coagulant activity, but both von Willebrand factor antigen, activity levels and factor V coagulant activity remained low. Moreover, there was no rapid decline in factor VIII complex activity. These findings suggest that the endogenous factor VIII in this patient is metabolized normally and that at least the deficiency of factor VIII does not result from accelerated degradation in plasma.
 ...
PMID:[DDAVP administration in a case of congenital combined factor V and factor VIII deficiency]. 260 19

Influence of the protein C activator from snake venom on blood coagulation was studied. Incubation of different concentrations of the activator with rat blood plasma resulted in a dose-dependent prolongation of the activated partial thromboplastin time (APTT). Cleavage of the protein C to the active form was detected by electrophoresis. Intravenous administration of the activator (100 mg/kg) into rats led to prolongation of APTT to 242 +/- 80%, to increase in the plasminogen activator level to 145 +/- 29% and to decrease in the factor V activity to 57 +/- 14%. When thrombosis was induced by means of administration of the thromboplastin lethal dose, pretreatment with the activator prevented animal death in 90% of cases. The effects of the activator observed appear to occur via transformation of the endogenous protein C into its active form.
 ...
PMID:[Antithrombotic effect of protein C activator from a snake venom]. 261 27

To elucidate the role of protein C (PC) in the release of plasminogen activator inhibitor (PAI) from endothelial cells, the effect of PC and activated protein C (APC) on plasma levels of PAI in endotoxin (ET)-treated rats was examined. When activated by snake venom, human PC significantly prolonged the activated partial thromboplastin time (APTT) of both human and rat plasma samples. Addition of APC also prolonged the APTT of both human and rat plasma samples. PAI activity in plasma from septicemic patients and ET-treated rats was neutralized by APC. A small dose of ET (0.1 microgram/kg) gradually increased plasma PAI activity, which became maximum 3h after ET-treatment. APC administered prior to ET-treatment, PC decreased PAI activity, however, no such inhibition was seen when administered after ET-treatment. A significant negative correlation between PC concentrations and PAI activities was observed in plasma from septicemic patients. These findings indicated that activation of PC on endothelial surface plays a regulatory role in releasing PAI and that endotoxin might inhibit the surface activation of PC.
 ...
PMID:[Role of protein C in endotoxin-induced release of plasminogen activator inhibitor from endothelial cell]. 261 61

As part of a European multicentre prospective study involving the measurement of a number of haemostatic factors, a quality assessment (QA) scheme was organized. This paper describes the preparation, design and results of the first QA exercise, involving 16 European laboratories and 10 haemostatic assays. The design allowed the investigation, for each assay, of the variability between duplicates and the variability between days within each centre, and of the agreement between centres. A graphical presentation of each centre's performance in comparison to that of others was adopted, which preserved the confidentiality of each centre's results. The factor VIII clotting activity assay (VIII:C) and the rocket immuno-electrophoresis assays of von Willebrand factor related antigen (vWF R:Ag), antithrombin III, protein C and histidine-rich glycoprotein showed the highest between-duplicate and between-day coefficients of variation (CVs), whereas the clotting assays of activated partial thromboplastin time and fibrinogen had the lowest CVs. CVs for the enzymatic assays using synthetic substrates of antithrombin III, plasminogen and alpha-2-antiplasmin were between these extremes. The between-centre CVs were high for both the VIII:C and vWF R:Ag assays. The QA exercise showed that, in multicentre studies involving the measurement of haemostatic factors, it is feasible to undertake analysis locally at each centre.
 ...
PMID:The measurement of haemostatic factors in 16 European laboratories: quality assessment for the Multicentre ECAT Angina Pectoris Study. Report from the European Concerted Action on Thrombosis and Disabilities (ECAT). 266 75

Eighty patients undergoing total hip replacement (THR) were randomly allocated to three groups. Group I (n = 29) received general anaesthesia, Group II (n = 29) epidural anaesthesia and Group III (n = 22) the same epidural as Group II and the same general anaesthesia as Group I but with a lower isoflurane concentration. Prothrombin time (PT), activated thromboplastin time (APTT), fibrinogen (FG), plasminogen (PG), antithrombin III (AT III), protein C (Proc C), alpha-2-antiplasmin (alpha 2AP), Factor VIII coagulating activity (F VIII:C), von Willebrand factor antigen (vWF:Ag), von Willebrand ristocetin cofactor (vWF:Rcof), tissue plasminogen activator (tPA) as antigen and activity were measured before induction (A), at the end of surgery (B), on the first postoperative morning (C) and 7 days postoperatively (D). The most relevant finding was that AT III was equally depressed immediately after surgery in all groups, but returned to normal significantly faster in the epidural group (mean values at C: 96.2% in Group I, 104.1% in Group II, 92.7% in Group III). The faster return to normal of AT III after epidural anaesthesia could be one of the mechanisms responsible for the beneficial effect of this technique on the prevention of thromboembolic complications.
 ...
PMID:Coagulation and fibrinolytic parameters in patients undergoing total hip replacement: influence of the anaesthesia technique. 268 46


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>