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

Bleeding complications during liver transplantation have been attributed to accelerated fibrinolysis. In order to determine its cause, 11 adults (mean age: 38.9 +/- 13.2 yr) undergoing liver transplantation were studied. There were three groups of patients: cirrhosis (n = 4), fulminating hepatitis (n = 4) and one group including a primary biliary cirrhosis, a hepatic metastasis and a hepatoma. The following factors were studied in the immediate preoperative period, at different surgical times throughout the procedure and 2-3 h after the end of the abdominal sutures: platelet count, prothrombin concentration, fibrinogen, activated kephalin time, factors II, V, VII + X and VIIIc, antithrombin III, protein C, D-dimers, fibrinogen and fibrin degradation products (PDF), plasma plasminogen, tissue plasminogen activator (tPA) and the fast tPA inhibitor (PAi). Preoperatively, only the two patients with hepatic cancer had a normal haemostatic profile. Throughout the procedure, all patients had only moderate changes in platelets, coagulation factors and their inhibitors, and plasminogen, because platelet concentrates and fresh frozen plasma were transfused. Levels of tPA rose, becoming very high during the anhepatic period and just after graft reperfusion. An abrupt fall occurred at the end of surgery. There were important individual differences in tPA activity. PAi activity was low during the preanhepatic and anhepatic stages, rising rapidly after revascularization.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Fibrinolytic activity in patients undergoing hepatic transplantation]. 249 27

Lupus anticoagulant, concentrations of anticardiolipin antibodies, antithrombin III, plasminogen, (free) protein S, protein C, prothrombin, platelet counts, and bleeding times were determined in 74 lupus patients (58 with systemic lupus erythematosus; 16 with lupus-like disease) to establish the presence of risk factors for thrombosis in these patients. Of the variables evaluated, lupus anticoagulant had the strongest association with a history of thrombosis. Both positive anticardiolipin antibody concentrations and the presence of (mild) thrombocytopenia were significantly associated with a history of thrombosis and the presence of lupus anticoagulant. Reduced concentrations of antithrombin III, plasminogen, (free) protein S, and protein C were found in some patients but were not associated with either thrombosis or lupus anticoagulant. Mean concentrations of total protein S were significantly lower in patients with thrombosis than in those without and in patients with lupus anticoagulant than in those without. The antigenic concentration of prothrombin was reduced in 3/74 (4%) lupus patients. These three patients had lupus anticoagulant but no history of thrombosis, which suggests that a low prothrombin concentration protects patients with lupus anticoagulant from the development of thrombosis. A prolonged bleeding time was associated with the presence of lupus anticoagulant but not with a history of thrombosis. Analysis by stepwise logistic regression did not disclose additional risk factors for thrombosis in lupus patients with lupus anticoagulant. Increased antithrombin III concentrations and decreased free protein S concentrations are often found in lupus patients, unrelated to lupus anticoagulant or thrombosis.
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PMID:Risk factors for thrombosis in lupus patients. 251 63

55 consecutive patients (28 males and 27 females) who had suffered from (recurrent) venous and/or arterial thromboembolism were evaluated for laboratory findings of thrombophilia. At the time of investigation, 15 patients were taking oral anticoagulants. In addition to patient and family history and clinical examination, a coagulation profile, euglobulin clot lysis time before and after venous occlusion, assays of plasminogen, antithrombin III, protein C (PC), free protein S (PS[f]), and C4b binding protein bound protein S (PS[b]) were obtained. 2 patients not orally anticoagulated had partial PD deficiency with functional PC activity values of 53% and 57% respectively, as compared to normal human plasma (NHP). Functionally active PS(f) was found to be lower than normal in 14 patients not taking oral anticoagulants and without signs of hepatopathy. In 4 of these 14 patients partial PS deficiency was present (PS[f] between 7 and 37% of NHP, and PS[b] between 51 and 86% of NHP). In one of these 4 subjects the hereditary nature of PS deficiency was proven by investigation of family members. In 3 of the 14 patients a shift from PS(f) (between 34 and 66%) towards PS(b) (124-141%) was found. The remaining 7 patients showed subnormal PS(f) values (56-64%) and normal PS(b) values (78-105%). In the patients receiving oral anticoagulant therapy, PC and PS levels were diminished. Statistically there was no close relationship between PC and PS levels on the one hand and prothrombin time values on the other. In anticoagulated patients, therefore, PC or PS deficiency can only be diagnosed by investigation of members of the propositus's family.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Hemostasis parameters in 55 patients with venous and/or arterial thromboembolisms]. 252 96

The effect of human skin mast cell tryptase on human plasma proenzymes (prothrombin, coagulation factor XII, complement C1s, protein C and plasminogen) was investigated. Tryptase had no effect on these proenzymes, when incubated with them at 37 degrees C for up to 90 min, as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and by the ability to hydrolyze specific peptide p-nitroanilide substrates. After prolonged treatment with tryptase, proenzymes could be fully activated with their specific activators. The results indicate that tryptase neither activates these plasma proenzymes nor inactivates the corresponding active enzymes. As a positive control, the tryptase preparation was also incubated with human fibrinogen and rat thymus histones. Prolonged treatment with tryptase increased the thrombin-induced clotting time of fibrinogen. Tryptase also efficiently hydrolyzed histone H1 from rat thymus. Histones H3/H2B and H2A were hydrolyzed less efficiently than H1, and no hydrolysis of histone H4 by tryptase was detected under the experimental conditions.
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PMID:Effect of human mast cell tryptase on human plasma proenzymes. 253 Jan 78

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.
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PMID:The serial hemostasis-related changes in patients with cerebral infarction: comparison between progressing and non-progressing stroke. 253 1

In order to determine a scheme for the screening of inherited thrombotic disorders, abnormalities considered as predisposing to thrombosis have been reviewed. Owing to the low prevalence of biological alterations, a selection of patients is required: documented venous thromboses, possibly at unusual sites (mesenteric vein, portal, cerebral veins), occurring before the age of 40 in patients with a positive family history of thromboses are relatively frequently associated with coagulation abnormalities. In addition, patients with skin necrosis at the initiation of oral anticoagulants, or with repeated superficial vein thrombosis or unexplained arterial occlusions at a young age might be included for screening. Tests have also to be selected. Some abnormalities, such as congenital deficiencies in antithrombin III, protein C and protein S, are recognized risk factors and have to be searched. Some others cannot be at present considered as definite risk factors (e.g., dysfibrinogenemias or deficiencies in factor XII), but their detection is easy by routine tests: prothrombin time, fibrinogen assay. Other abnormalities are recognized risk factors (or not) and need specific uncommon tests (e.g., study of fibrinolysis). Each time a biological abnormality is found, it is important to verify it is isolated since combined deficiencies have been observed and we should be able to answer the question whether the abnormality is the cause or the consequence of thrombosis, or a coincidence. Finally, in our experience, even in well selected patients, a coagulation disorder is detected in less than 30% of patients, so that new tests are needed to improve our knowledge in this field.
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PMID:Screening for inherited thrombotic disorders. 253 41

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.
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PMID:[DDAVP administration in a case of congenital combined factor V and factor VIII deficiency]. 260 19

Using affinity chromatography on a column of factor X-Cellulofine, we have isolated a novel blood coagulation factor X-binding protein with anticoagulant activity from the venom of Trimeresurus flavoviridis (Habu snake). This anticoagulant protein was also purified by chromatography on Sephadex G-75 and S-Sepharose Fast Flow. The yield of the purified protein was approximately 16 mg from 400 mg of crude venom. The purified protein gave a single band on both analytical alkaline disc-gel electrophoresis and SDS-PAGE. This protein had a relative molecular weight (Mr) after SDS-PAGE of 27,000 before reduction of disulfide bonds and 14,000 after reduction of disulfide bonds. The protein prolonged the clotting time induced by kaolin or factor Xa. In the presence of Ca2+, it formed a complex with factor X, the molar ratio being 1 to 1. Similar complex formation was observed with factor Xa and factor IX/factor IXa, but not with other vitamin K-dependent coagulation factors, i.e., prothrombin, factor VII, protein C, protein S, and protein Z. The interaction of this anticoagulant protein with factor IX/factor X was dependent on gamma-carboxyglutamic acid (Gla) domains, since Gla-domainless derivatives of factor X and factor IXa beta' did not interact with this anticoagulant protein.
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PMID:A novel blood coagulation factor IX/factor X-binding protein with anticoagulant activity from the venom of Trimeresurus flavoviridis (Habu snake): isolation and characterization. 261 88

Fibronectin (FN) is a protein which acts as an opsonin and participates in anti-infective mechanisms. We measured FN in cord blood from 39 normal newborns by Laurell's electroimmunoassay. The mean value of FN was 13.5 +/- 6.8 mg/dl, lesser then mean value of 26 normal children 1 mo. to 7 y. old, 27.3 +/- 8.7 mg/dl (p less than 0.001). FN continued being low, 14.1 +/- 8.1 mg/dl al 48 h. of age. Nevertheless it was normal at 15 days of age (24.6 +/- 9.7 mg/dl). FN levels were lower at 15 days of age in 19 newborns who received vitamin K (12.2 +/- 6.1 mg/dl) than in the group which was not treated (18.1 +/- 9.9 mg/dl) but the difference was not significant (p greater than 0.05). There was a close correlation between cord blood levels and levels at 48 h. (p = 0.001) and levels at 15 d. (p = 0.003). There was no relationship either with the gestational age and birth weight, no prothrombin and protein C levels. The FN decrease in the newborn can be one of the causes of the opsonization deficiency, nevertheless normalization occurred very soon, before the second week.
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PMID:[The fibronectin deficiency in normal newborn infants corrects itself very quickly]. 261 29

This report summarizes the documented cases of homozygous protein C deficiency in the United States and Europe. Procedures for diagnosing and treating this disorder (both initially and over the long term) have been compiled by a working party on homozygous protein C deficiency of the Subcommittee on Protein C of the International Committee on Thrombosis and Haemostasis. Homozygous protein C deficiency is an autosomal recessive disorder that usually manifests itself by purpura fulminans and, less commonly, by massive large vein thrombosis; severe diffuse intravascular coagulation also develops in these infants, and there is evidence of intrauterine thrombosis. For confirmation of homozygous protein C deficiency in a neonate with purpura fulminans or massive venous thrombosis, the infant should have undetectable protein C activity and both parents should be heterozygous for protein C deficiency. At the onset of symptoms, the initial treatment should be plasma (8 to 12 ml/kg every 12 hours) until all lesions have healed. Two modalities for long-term treatment are accepted as useful in these children: oral anticoagulant therapy or protein C replacement (fresh frozen plasma or prothrombin complex concentrate). Liver transplantation has been performed in only one child, with success. Oral anticoagulation (vitamin K antagonists, maintaining the prothrombin time from one and one-half to two times control values or at the International Normalized Ratio of 2.5 to 4.4) is our recommendation of choice for long-term treatment. With appropriate care, these children are able to be free of coagulopathy and live relatively normal lives.
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PMID:Diagnosis and treatment of homozygous protein C deficiency. Report of the Working Party on Homozygous Protein C Deficiency of the Subcommittee on Protein C and Protein S, International Committee on Thrombosis and Haemostasis. 264 43


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