Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0409974 (lupus)
 22,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Livedoid vasculitis, a hyalinizing vasculopathy, is characterized by extensive formation of microthrombi and deposition of fibrin in the middermal vessels, which result in epidermal infarction, ulceration, and formation of stellate scars. In a prospective study of nonhealing ulcers in patients with livedoid vasculitis, we found a high incidence of anticardiolipin antibodies, lupus anticoagulants, increased levels of plasminogen activator inhibitor, and low levels of endogenous tissue plasminogen activator (t-PA) activity. This procoagulant tendency and decreased fibrinolysis may provide an explanation for the occlusive vasculopathy often noted in biopsy specimens from these patients. On the basis of these findings, we proposed that fibrinolysis with recombinant t-PA would lyse microvascular thrombi, restore circulation, and promote wound healing. In six patients who had nonhealing ulcers caused by livedoid vasculitis and in whom numerous conventional therapies had failed, low-dose t-PA (10 mg) was administered intravenously during a 4-hour period daily for 14 days. Five of the six patients had dramatic improvement; almost complete healing of the ulcers occurred during hospitalization, and tissue oxygenation, as measured by transcutaneous oximetry, increased. The one treatment failure was due to rethrombosis of the microvasculature; this patient was subsequently re-treated but with concurrent anticoagulation, and her leg ulcers healed. We conclude that daily administration of a low dose of t-PA is safe and effective treatment for nonhealing ulcers due to occlusive vasculopathy.
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PMID:Tissue plasminogen activator for treatment of livedoid vasculitis. 143 47

Ocular vascular occlusive disease resulting in severe retinopathy and/or post-thrombotic glaucoma has been extensively discussed in patients with lupus anticoagulant and/or anticardiolipin antibodies (LA/aCL). Inadequate circulation plays an important role in the pathogenesis of another ophthalmic entity--the normal tension glaucoma. We studied 22 patients with normal tension glaucoma (group I) and 23 with chronic open-angle glaucoma (group II) and compared them with a control group (n = 25, group III). LA, aCL, the aCL cofactor beta 2-Glycoprotein I, and other haemostatic parameters including factor VIII:C, von Willebrand factor, factors II, V, VII and plasminogen activator inhibitor were measured. Five out of 22 (22.7%) in group I, five out of 23 (21.7%) in group II and three out of 25 (12.0%) in group III had positive LA and/or aCL. These prevalences were not statistically significantly different. beta 2-Glycoprotein I was normal in all groups. No other parameters were significantly different between groups. These findings do not support the contribution of ocular microvascular occlusive disease, due to elevated aCL, in the pathogenesis of glaucomatous damage.
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PMID:Lupus anticoagulants/anticardiolipin antibodies in patients with normal tension glaucoma. 145 Mar 20

We studied the natural inhibitors (NI) of blood coagulation and fibrinolysis in 50 patients with lupus anticoagulant (LA), in order to identify possible alterations of these NI, that could favour thrombotic manifestations. We found no statistically significant difference in antithrombin III, protein C and alpha 2-antiplasmin between controls and patients with LA, irrespective of their clinical manifestations. We found an increase of plasminogen activator inhibitor (PAI, P < 0.001) and a decrease of free protein S (PSf, P < 0.001) and total protein S (PSt, 0.01 < P < 0.05) in the patients with LA when compared with the control group. We found no difference in the levels of NI between patients with thrombosis (n = 19) and without thrombosis (n = 31) nor between patients with (n = 25) or without thrombosis and/or foetal loss (n = 25). In contrast, we observed a decrease of PSf in women with foetal loss (n = 10) as compared with women without foetal loss (n = 22, 0.01 < P < 0.05) and a decrease of PSf when comparing 19 patients with systemic lupus erythematosus (SLE) with 31 patients without SLE (0.01 < P < 0.05). These findings show that the patients with LA had several abnormalities in the NI system, but there was no significant association between levels of PAI, PSf, PSt and a history of thrombosis.
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PMID:Natural inhibitors of blood coagulation and fibrinolysis in patients with lupus anticoagulant. 148 97

Increased thrombogenesis observed in systemic lupus erythematosus (SLE) is derived from multiple mechanisms, including: Enhanced coagulation factor VIII:VWf activity, lupus anticoagulants, anti-phospholipid antibodies, acquired deficiencies of natural anti-thrombotic mechanisms (protein C, protein S, anti-thrombin III), and impaired fibrinolytic mechanisms. We studied the fibrinolytic mechanisms of 18 patients with systemic lupus erythematosus, selected carefully to avoid other possible causes of abnormalities in the fibrinolytic activity. Despite the fact that the euglobulin lysis time in steady state was normal in all instances, disturbances in the tissue plasminogen activator/plasminogen activator inhibitor (TPA/PAI) system were found in all SLE patients: TPA activity was undetectable in all cases, whereas it was above 0.4 IU/ml in a control group. In 72 percent of patients, the undetectable TPA activity was correlated with abnormally high PAI activity; PAI levels were normal in all members of the control group, their mean value being 0.74 versus 8.63 IU/ml for SLE patients (P less than .01). Coagulation protein C deficiency was found in 3 patients (17%). Even though within normal range, fibrinogen levels were significantly higher in SLE than in normal controls (219 versus 192 mg/dl, P less than .01) and plasminogen levels were significantly higher in SLE than in controls (117 versus 78.2%, P less than .01). Cross-linked fibrin derivatives (D-D dimers) were negative in all patients with SLE. Sixty-eight percent of SLE patients had high levels of antiphospholipid antibodies, but no correlation with the disturbances of the TPA/PAI system was found. It is concluded that most patients with SLE display severe abnormalities in the TPA/PAI anti-thrombotic system and that these abnormalities may be related to the lupus thrombophilia, apparently multifactorial in its origin.
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PMID:Disturbances in the tissue plasminogen activator/plasminogen activator inhibitor (TPA/PAI) system in systemic lupus erythematosus. 190 23

Although Virchow postulated 100 years ago that hypercoagulability states exist, it has only been in recent years that methods of documenting hypercoagulability have been developed. These clotting tendencies can be acquired or congenital. The common causes of acquired clotting tendencies include conditions which result in tissue and cellular damage, shock, transfusion reactions, and tissue necrosis. Certain drugs and drug reactions, and certain disease states which include blood dyscrasias and cancer are also associated with clotting problems. In certain diseases such as homocystinuria, hyperlipidemia, and lupus erythematosus, abnormal clotting tendencies may also develop. Important advances in the recognition of hypercoagulability have come with the documentation that congenital clotting abnormalities exist. Moreover, these abnormalities are proving to be more common than are congenital bleeding syndromes. Patients who appear to have spontaneous clotting manifestations and are under 40 years of age should be screened for one of these abnormalities. These congenital clotting tendencies can be classified as defects in thrombosis inhibitors, dysfibrinogenemias, or defects in fibrinolysis. The first thrombotic inhibitor defect recognized was antithrombin III deficiency which was reported in 1965. Subsequently, Protein C, Protein S, and Heparin cofactor II deficiencies have been recognized as contributing to thrombotic tendencies. Dysfibrinogenemias are relatively rare and most are associated with bleeding problems; however, 11% of the abnormal fibrinogens are associated with a clotting tendency. The reason appears to be that these fibrins are resistant to fibrinolysis. The most common defects which are associated with thrombotic tendencies appear, at the present time, to be due to defects in fibrinolysis. These include hypoplasminogenemia, decreases in plasminogen activator, increases in plasminogen activator inhibitor, and Factor XII deficiency.
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PMID:Acquired and congenital clotting syndromes. 223 69

Lupus anticoagulants (LA) are IgG or IgM antibodies against phospholipids which in vivo represent an important thrombophilic factor despite their in vitro anticoagulant activity. We investigated the fibrinolytic system of 20 patients with connective tissue disease and positive LA, compared to a control group of 24 age- and disease-matched patients without LA. There was no statistically significant difference of alpha 2-antiplasmin, plasminogen, fibrinogen, t-PA activity, D-dimers and heparin cofactor II, between the two groups. Although t-PA was uniformly low in both groups, plasminogen activator inhibitor activity (PAI) was significantly higher in LA cases (p less than 0.001). Increased PAI levels represent an inhibitory factor of the fibrinolytic defense mechanism, which together with other functional deviations may contribute to the thrombophilic tendency of LA patients.
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PMID:Impaired fibrinolysis as an essential contribution to thrombosis in patients with lupus anticoagulant. 250 94

We investigated the effect of plasma and serum from 10 subjects with the lupus anticoagulant and thrombosis and 9 normal subjects on the secretion of tissue-type plasminogen activator (t-PA) and its rapid inhibitor (type 1 plasminogen activator inhibitor, or PAI-1) by cultured human endothelial cells. Confluent monolayers of human umbilical vein endothelial cells were incubated for 48 hours with plasma or serum diluted ten-fold in serum-free endothelial cell growth medium, and the secretion of t-PA and PAI-1 measured by enzyme-linked immunosorbent assay. No consistent differences in mean t-PA and PAI-1 release were found between cells exposed to normal plasma or serum and plasma or serum from subjects with the lupus anticoagulant and thrombosis. No plasma or serum sample produced consistent inhibition of t-PA release or stimulation of PAI-1 release (defined as t-PA levels less than the mean minus two standard deviations for normal subjects, and PAI-1 levels greater than the mean plus two standard deviations for normal subjects, respectively). These findings do not support a role for altered endothelial fibrinolytic activity in the pathogenesis of thrombosis in subjects with the lupus anticoagulant, and are consistent with previous observations that these subjects have normal fibrinolytic activity in vivo.
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PMID:Effect of the lupus anticoagulant on endothelial fibrinolytic activity in vitro. 250 1

A 51 year-old man with a history of deep venous thromboses and recurrent pulmonary embolism on long-term anticoagulant treatment was admitted to our department because of insidious onset thrombocytopenia. He had neither a history nor clinical signs of abnormal bleeding. On admission, the platelet count was reduced to 21 x 10(9)/l, platelet associated IgG was increased, and bone marrow specimens showed megakaryocytic hyperplasia. Platelet survival was slightly shortened with enhanced platelet sequestration in a normal size spleen. Laboratory evaluation after discontinuation of anticoagulant treatment revealed persisting prolongation of both the prothrombin time and the activated partial thromboplastin time which could be attributed to the presence of a lupus-type circulating anticoagulant. Further relevant laboratory findings included an elevated titer of IgG anti-cardiolipin antibodies and a reduced euglobulin clot lysis activity after venous occlusion due to increased plasminogen activator inhibitor activity. In recent years, it has become apparent that a striking correlation exists between the presence of antibodies to phospholipids and thromboembolic disease and immune thrombocytopenia respectively. The present case report on the association of these autoantibodies with both, recurrent venous thromboembolism and severe thrombocytopenia, supports the hypothesis that anti-phospholipid antibodies may play a crucial part in the pathogenesis of these clinical conditions. A reduced vascular fibrinolytic capacity may be involved in the thrombophilic state induced by anti-phospholipid antibodies.
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PMID:[Anti-phospholipid antibody with recurrent venous thromboembolism and severe autoimmune thrombocytopenia]. 250 50

Fibrinolysis was evaluated in 16 women with SLE, who were divided into three groups of increasing disease severity according to their past history, and in 10 normal subjects. Fibrinolysis parameters assessed were tissue-type plasminogen activator (t-PA) activity in plasma and in euglobulin fractions and rapid plasminogen activator inhibitor activity. All parameters were evaluated before and after venous occlusion to assess endothelial cell t-PA release in response to localized anoxia. Markers of deficient fibrinolysis were persistently undetectable t-PA activity and increased rapid plasminogen activator inhibitor activity after venous occlusion. Defective fibrinolysis was correlated with disease severity; it was noted only in patients with severe or moderate disease and in no patients with mild disease or in controls. Fibrinolysis abnormalities were independent of disease activity, suggesting that vascular endothelium injuries occurring during flare-ups persist during inactive phases of the disease. No correlation was found between fibrinolysis abnormalities and disease duration, corticosteroid administration, or the presence of lupus anticoagulant or anticardiolipin antibodies. These data support the hypothesis of parallelism between the severity of vascular injuries, suggested by deficient fibrinolysis, and the severity of clinical manifestations in SLE.
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PMID:Fibrinolysis abnormalities in systemic lupus erythematosus and their relation to vasculitis. 312 85

Two classes of antiphospholipid antibodies (APA) are associated with adverse pregnancy outcomes. Those APA identified by immunoassays using phospholipid-coated surfaces (e.g., anticardiolipin antibodies) seem to bind to the 57 kD anticoagulant protein, beta 2-glycoprotein-I, when complexed with anionic phospholipid bilayers. Such APA may or may not prolong phospholipid-dependent clotting assays. A second class of APA are identified by their interference with phospholipid-dependent clotting assays (i.e., lupus anticoagulants). The latter bind to phospholipids present in a unique hexagonal phase either alone or complexed with prothrombin or beta 2-glycoprotein-I. There is evidence that both classes of APA are directly responsible for adverse pregnancy outcomes including spontaneous abortions, stillbirths, fetal growth retardation, thrombosis, thrombocytopenia, and preeclampsia. Putative APA-mediated pathogenic mechanisms include intervillous thrombosis, intravillous infarctions and decidual vasculopathy. The thrombogenicity of APA may result from their interference with endothelial phospholipids required for antithrombin III and protein C and S anticoagulant activity and prostacyclin synthesis and/or increased endothelial expression of the procoagulants: tissue factor, von Willebrand factor, platelet-activating factor, and plasminogen activator inhibitor type-1. Other prothrombotic properties seem to include: increased platelet aggregation, and reduced beta 2-glycoprotein-1 and annexin V anticoagulant activity. Rigorous diagnostic criteria must be applied to the detection of both classes of APA because the prevention of adverse pregnancy outcomes requires potentially hazardous anticoagulant therapy.
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PMID:The immunobiology and obstetrical consequences of antiphospholipid antibodies. 752 11


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