Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0149871 (deep vein thrombosis)
 12,364 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Elevated levels of antiphospholipid antibodies are associated with an increased risk of thrombosis. To establish the prevalence of these antibodies in deep vein thrombosis (DVT), IgG and IgM antibodies to cardiolipin (aCL) and phosphatidylserine (aPS) were determined by enzyme-linked immunosorbent assay in 118 patients with DVT either during an acute episode (N = 53) or at least 2 months after acute DVT (N = 65). Most patients (76%) had proximal leg DVT and no one had evident autoimmune disorder. aCL and aPS values higher than 4 standard deviations above the mean value of the control group (147 blood donors) were considered increased. Increased IgG aCL were observed in 10% of DVT patients (controls: 5%, not significant), increased IgG aPS in 16% of DVT patients (controls: 5%, p less than 0.005) and both types in 4% of DVT patients (controls: 3%, not significant). In the subgroup of 41 patients with previous idiopathic DVT, prevalence of increased IgG aPS was the highest: 27% (p less than 0.001). Increased antibodies of IgM isotype were observed in 3% (aCL) and 2% (aPS) of all DVT patients (controls: 8% and 4%, respectively, not significant). Elevated IgG aCL or aPS were not associated with significant changes in platelet count, antithrombin III and protein C. However, in patients with increased IgG aPS deficient fibrinolysis due to high plasminogen activator inhibitor activity was observed before and after 20 min upper arm venous occlusion. DVT patients with increased IgG aPS might be exposed to a greater risk of rethrombosis due to deficient fibrinolysis than DVT patients without these antibodies.
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PMID:Prevalence of antiphospholipid antibodies in deep vein thrombosis and their relationship to blood coagulation and fibrinolysis. 175 96

6 patients with deep vein thrombosis triggered by drug therapy, that is oral contraceptives in 5 and the anticonvulsant tranexamic acid in 1, are described. These cases were among 40 symptomatic patients out of a total group of 81 with congenital coagulation inhibitor defects studied over 10 years at the Institute of Medical Semiotics, Padua, Italy. The 5 women with deep vein thrombosis ranged in age from 20-34, and had typically taken oral contraceptives containing 35 mcg ethinyl estradiol in combined or phasic preparations, for 1 to 8 cycles. One women, however, had been prescribed sequential pills containing 50 mcg mestranol. Another had taken oral contraceptives with impunity for 3 years, but developed deep vein thrombosis after taking tranexamic acid for 10 days. All recovered after heparin or oral anticoagulant therapy, except a 21 year old whose condition evolved into complete ileo-caval obstruction up to the renal veins, and was treated with urokinase. the congenital defects involved were 3 probable heterozygous true deficiencies of antithrombin III (low ATIII antigen and activity); a decreased protein C antigen to factor X antigen ratio; a heparin cofactor II deficiency; and a type I protein S deficiency (low free protein S, with normal total protein S and normal levels of C4B-bp.) While 5 of these 6 women had family histories of thromboembolic disease, the drug was prescribed without knowing that they were heterozygous for a coagulation inhibitor deficiency. The incidence of drug-induced thromboembolism was low in this series overall, where most of the events were triggered by surgery or trauma.
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PMID:The role of drugs, particularly oral contraceptives, in triggering thrombosis in congenital defects of coagulation inhibitors: a study of six patients. 178 39

An enzyme-linked immunosorbent assay (ELISA) for measuring total, free and complexed protein S in plasma was developed. To assay free protein S, C4b-binding protein-bound protein S (C4b-BP-PS) was extracted by addition of polyethyleneglycol (PEG) 6000 (5%, final concentration) to plasma samples. Microtiter plates were coated with rabbit anti-human protein S, and bound protein S was detected with labelled anti-protein S antibody. Diluted plasma samples were incubated in the plates overnight at 22 degrees C to permit C4b-BP-PS complexes to dissociate. Mean variation coefficients of 2.1 and 3.2% (intra-assay) and 4.3 and 7.9% (inter-assay) were found for total and free protein S assays, respectively. The ELISA measures free and complexed protein S with equal efficiency as is demonstrated by the fact that the sum of free protein S and C4b-BP-PS complex levels in normal individuals, women in their third trimester of gestation and patients with acute deep vein thrombosis (DVT), equaled the level of total protein S present in the corresponding plasma. Total protein S values obtained with the ELISA, in all groups studied, correlated well with those obtained with a standard electroimmunoassay (EIA) (r = 0.93; n = 40). However, total protein S levels measured by EIA were lower than those assayed by ELISA in pregnant women and in DVT patients. Furthermore, addition of several amounts of purified C4b-BP to NHP, which reduced the recovery of free protein S, did not influence the total protein S values measured by ELISA but slightly decreased the recovery of total protein S measured by EIA. These results indicate the necessity of using assays which accurately and reliably measure the total amount of protein S antigen. After addition of C4b-BP to NHP, the residual functional protein S level was lower than the residual level of free protein S antigen; this lends support to the idea that C4b-BP-PS complex inhibits the activated protein C cofactor activity of protein S.
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PMID:Determination of total, free and complexed protein S in plasma by ELISA, and comparison with a standard electroimmunoassay. 183 53

Anticoagulation is being used increasingly in the critical care areas. Thrombolytic therapy is now commonly used in emergency departments and coronary care units for treatment of AMI. Heparin therapy for unstable angina and for a 48 to 72 hour period following thrombolytic therapy for AMI is becoming commonplace. Beginning warfarin therapy concomitantly with heparin to decrease the total duration of heparin and the duration of hospital stay for DVT therapy is encouraged. The use of low-dose warfarin to prevent DVT in hip surgery, improve catheter patency, and prevent catheter-related subclavian thrombosis is increasing. Along with the increased use of anticoagulation must come a greater appreciation of the complications associated with the agents used, and of how to prevent or treat the hemorrhagic or thrombotic morbidity that may arise. Acute hemorrhage with thrombolytic agents must be recognized and the immediate implementation of conservative and aggressive measures begun. Heparin-induced thrombocytopenia with thrombosis is an often-unrecognized problem that may occur in 1% to 2% of heparin recipients and result in limb amputations. A delayed onset (6-10 days) requires frequent platelet counts for early diagnosis and treatment. The resurgence of warfarin use for prevention of cardiovascular and cerebrovascular disorders demands observation for skin necrosis from protein C and S inhibition. Early recognition of symptoms and syndromes associated with organ system hemorrhage in patients receiving chronic anticoagulation is imperative. The use of antagonists, such as protamine sulfate for heparin, vitamin K1 for warfarin, and antifibrinolytic drugs for thrombolytic agents, may be necessary in treating hemorrhagic events. However, their use may worsen the thromboembolic event initially treated.
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PMID:Toxic effects of drugs used in the ICU. Anticoagulants and thrombolytics. Risks and benefits. 186 82

Protein C deficiency is a known underlying risk factor for thromboembolic disease. Most commonly it presents as thrombophlebitis, deep venous thrombosis or pulmonary embolism. Less common presentations are becoming increasingly recognized now that assays for protein C are more widely available. We present two cases of mesenteric venous thrombosis who were found to have protein C deficiency.
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PMID:Mesenteric venous thrombosis due to protein C deficiency. 193 24

Experimental models of deep venous thrombosis, heretofore, have not been available for laboratory studies. This investigation establishes a novel model of venous thrombosis by inhibiting the protein C system combined with venous stasis and subtle venous injury. Ten adolescent baboons were studied in pairs, with one animal receiving saline solution (B2, B4, B6, B8, B10) and one being exposed to thrombogenic reagents (B1, B3, B5, B7, B9). These reagents represented a combination of a monoclonal antibody (HPC4) to protein C, 1 to 4 mg/kg administered over 5 minutes, and tumor necrosis factor administered over 3 minutes at a dose of 150 micrograms/kg through a catheter placed into the left superficial femoral vein with distal ligation. To encourage stasis, a pediatric size blood pressure cuff was inflated to 40 mm Hg on the right thigh for 50 minutes of every hour during the first experimental day (day 1) in B5 to B10. The animals were observed for a 6-hour period on day 1 and then for an 11- to 15-day period until sacrifice. Hemodynamic and hematologic parameters were recorded along with duplex imaging of the iliac veins and inferior vena cava on a daily basis. Venography was performed on day 1, day 4, and the day of sacrifice. At sacrifice the entire iliac and vena caval system was carefully dissected, opened, and photographed. Experimental animals given the HPC4 and tumor necrosis factor developed left iliac vein thrombosis extending into the inferior vena cava. Duplex imaging, venography, and autopsy revealed that control animals receiving saline solution never developed comparable thrombus. Experimental subjects exhibited thrombus on duplex imaging by day 4 (B1), day 3 (B3), day 2 (B5), 120 minutes (B7), and 360 minutes (B9) after receiving HPC4 and tumor necrosis factor. Venograms performed on day 1 exhibited thrombus in B5, B7, and B9. The extent of thrombus, the timing of its occurrence, and its effect on the animals' left leg followed a dose-dependent relationship for the animals in which the occlusive blood pressure cuff was used. Significantly greater declines in blood pressure, white blood cell count, and platelet count were found in affected animals given HPC4 and tumor necrosis factor reagents as compared to control subjects. All affected animals demonstrated the appearance of fibrin split products and a markedly prolonged prothrombin time. This investigation, for the first time, establishes a reproducible model of deep venous thrombosis involving inhibition of protein C that will facilitate further laboratory studies on venous thrombosis.
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PMID:Deep venous thrombosis in the baboon: an experimental model. 194 66

Defibrotide, a deoxypolyribonuclide, has been found to modulate endothelial cell function causing increase in t-PA and decrease in PAI levels and also increase in PGI2 production. In addition, it increases platelet c-AMP levels and decreases MDA and TXB2 formation in human. Defibrotide inhibits platelet aggregate formation in vitro experiments as well as end-to-end anostomosis in rats. So, defibrotide inhibits the activation of platelets. Besides an increase of protein C and S levels a synergic action of heparin was observed in animal experiments. A strong antithrombotic effect has been observed in animal models. The drug has a beneficial effect in the cases of DVT, POVD, stroke and thromboembolism. Through its action we may say that the drug acts in a novel fashion in contrast to the other drugs used in this area. Defibrotide is a single-stranded polydeoxyribonucleotide obtained from deoxyribonucleic acid of mammalian lungs by controlled depolimerization. Since 1981 in our laboratory and in the clinical department we have been investigating a newly developed agent defibrotide in vitro experiments, animal experiments, and also its clinical pharmacology and clinical application. Some of our findings are already published and compared with literature (40, 43, 46). Because of the limited space we are not going to review the literature in detail but we are going to summarize our observations on this compound in the following order. I--in vitro experiments, II--Animal experiments, III--clinical pharmacology in human.
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PMID:The pharmacology and clinical pharmacology of defibrotide: a new profibrinolytic, antithrombotic and anti-platelet substance. 210 24

Protein C (PC) is the central component of a major antithrombotic regulatory system with both anticoagulant and profibrinolytic properties. A deficiency of PC is one of several hereditary abnormalities of haemostatic proteins that have been described in patients with a propensity for thromboembolic complications. Major morbidity is often seen in these patients. The various aspects of hereditary PC deficiency in terms of clinical presentation, genetics, diagnosis and treatment of both homozygous and heterozygous states will be presented. In heterozygous deficiency, the levels of plasma PC are usually between 35% and 65% of normal, whereas the majority of normal individuals have levels between 70% and 130%. PC-deficient patients usually develop venous thrombotic complications between the ages of 15 and 40 years with a high incidence of DVT and pulmonary embolism. The majority of thrombotic lesions appear to develop spontaneously; others are associated with trauma, surgery or pregnancy. Treatment of symptomatic patients is initial heparin therapy followed by coumadin. After multiple thrombotic events, lifelong oral anticoagulant therapy is necessary. The potential complications of treatment are coumadin-induced skin necrosis, heparin-induced thrombocytopenia and bleeding. Homozygous PC deficiency, a rare but fatal hereditary condition, manifests itself with massive DIC and purpura fulminans in the newborn period. Effective treatment for these infants can be instituted with either oral anticoagulant therapy or PC replacement. The heterozygous deficiency of PC is similar to that found in other inherited disorders in that several genetic mechanisms are responsible for the expression of the disease. Both quantitative and qualitative decreases in PC exist, the former being type I deficiency and the latter, type II. The best initial diagnosis of either form involves a clotting (functional) assay while differentiation between the two also requires an antigenic (immunological) assay. Autosomal inheritance with significant variable penetrance is found with profound clinical implications. In summary, PC deficiency is one of a group of inherited disorders termed hereditary thrombotic disease, which may have serious implications for patient morbidity and mortality.
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PMID:Hereditary protein C deficiency: a review of the genetics, clinical presentation, diagnosis and treatment. 210 16

We have identified an inhibitor of the protein C anticoagulant pathway in the plasma of a patient with systemic lupus erythematosus and a history of recurrent deep vein thrombosis, fetal wastage, and seizures. The patient's plasma contained anticardiolipin antibodies as well as a weak lupus anticoagulant. Examination of this patient's plasma revealed normal levels of protein C and protein S antigen, normal levels of functional protein C, as well as essentially normal levels of every blood coagulation factor. In a modified prothrombin time assay, the activated protein C-mediated prolongation of the clotting time observed in normal plasma was not observed in this patient's plasma. Gel permeation chromatography of the patient's plasma revealed that the inhibitory material was a high molecular weight protein that coeluted with the IgM peak. The inhibitor did not appear to circulate as a complex with protein C, since the inhibitor could easily be separated from protein C during fractionation procedures, and did not interfere with the activation of protein C in plasma as assessed by a functional amidolytic assay. Our findings suggest that the recurrent thrombotic episodes observed in this patient may have occurred as a result of the patient's antiphospholipid antibody neutralizing specific phospholipids essential for the full expression of the anticoagulant activity of activated protein C.
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PMID:Impairment of the protein C anticoagulant pathway in a patient with systemic lupus erythematosus, anticardiolipin antibodies and thrombosis. 210 91

We examined a variety of hemostatic functions in a subset of patients participating in a multicenter trial of rt-PA in the treatment of DVT. There were declines in systemic levels of plasminogen and alpha 2-antiplasmin at 24 hours following therapy. Additionally, levels of protein C antigen and protein C activity were also seen to decrease over the same time course. We propose that therapy with rt-PA has more systemic effects than previously thought and suggest that the effect on protein C may have some role in reocclusion following thrombolysis.
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PMID:Plasminogen, alpha 2-antiplasmin, and protein C decline following infusions of recombinant tissue plasminogen activator. 212 22


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