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)

Resistance to activated protein C (RAPC) is a newly recognized hypercoagulable state that was first described in 1993. It has become apparent that RAPC is even more common than deficiencies in protein C, protein S, or antithrombin III (AT-III) and affects an estimated 5% of the general population. The majority of patients with RAPC have an abnormality in factor V (Arg506Gln), which renders factor Va resistant to degradation by activated protein C. Studies in 75 patients referred to the Hematology Laboratory at Walter Reed Army Institute of Research (WRAIR) over a 14-month period for evaluation of venous thromboembolism were reviewed to determine the percentage of those with RAPC. Of the 75 patients in the study, one was deficient in protein S, one was deficient in protein C, and none was deficient in AT-III. In contrast, 27 (36%) patients tested positive for RAPC. Blood was available for DNA analysis in 15 patients with RAPC. Of these 15 patients, nine (60%) tested positive for the Arg506Gln mutation in factor V. Six other patients with RAPC did not have the factor V mutation. Additional risk factors for thrombosis were immobility, obesity, use of oral contraceptives, and pregnancy. The majority of patients had deep venous thrombosis of the lower extremities; 71% had a recurrence if not placed on chronic anticoagulation therapy. Thus RAPC is a significant risk factor for venous thrombosis. Evaluation for inherited hypercoagulable states should include testing for this newly described condition.
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PMID:Resistance to activated protein C: a common inherited cause of venous thrombosis. 873 70

Inflammation often is considered a contributing factor to both thrombosis and disseminated intravascular coagulation. The molecular mechanisms that dictate which of these clinical manifestations will result from the inflammatory stimulus remain obscure. Bacterial infection and certain tumors are common initiators of the disseminated intravascular coagulant response. Complement activation resulting from bacterial infection shares with selected tumors the capacity to generate or release membrane particles that lack functional adhesion receptors and hence could circulate to amplify a disseminated intravascular coagulant response. We developed a model of venous thrombosis that resulted in localized thrombus formation without disseminated intravascular coagulation. The model involves infusion of tumor necrosis factor, blockade of protein C and a partial decrease in venous flow caused by ligation of the superficial femoral vein without obstruction of the deep formal vein. Infusion of phospholipid vesicles into this model resulted in amplification of a localized thrombotic response into a consumptive response. Seven different groups of animals were studied. The first three groups established the conditions necessary to produce deep vein thrombosis. The second four groups established the conditions necessary to produce disseminated intravascular coagulation. The infusion of phospholipid vesicles plus tumor necrosis factor and anti-protein C antibody resulted in consumption of fibrinogen, the production of thrombin/antithrombin complexes, a fall in platelet count, and venous thrombosis. Without ligation and catheterization phospholipid vesicles failed to produce the consumptive response. We conclude, therefore, that phospholipid vesicles can amplify a local thrombotic response into a consumptive response, and that vesiculation accompanying inflammation is one means by which localized coagulant activity may be amplified to produce disseminated intravascular coagulation.
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PMID:Infusion of phospholipid vesicles amplifies the local thrombotic response to TNF and anti-protein C into a consumptive response. 874 82

Hereditary protein S deficiency (HSPD) is a predisposing factor to recurrent venous thrombosis but is not currently associated with stroke. We report two cases of HSPD revealed by stroke in young adults. The first one was a 36-year-old patient whith a pure motor hemiplegia, who gradually recovered without sequelae. Total and free protein S was decreased (55 and 10%). One of his brothers died from pulmonary embolism at 20 years and a sister had low protein S level without clinical signs. The second case was a 26-year-old patient who had a right hemiplegia with aphasia due to an infarction in middle cerebral artery area. He partially recovered, but the course of the illness was complicated by deep venous thrombosis of the lower limbs and pulmonary embolism. Total and free serum protein S level was severely decreased (25 and 0%). The patient's mother and one of his sisters also had low protein S but never had clinical complications. In both case, dupplex scanning, transcranial doppler, echocardiography, serum antithrombin III and protein C were normal. Cigarette smoking was the only risk factor for arterial disease. These two cases suggest that HSPD must be investigated in young patients with stroke, even in cases of lacunar stroke.
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PMID:[Cerebrovascular complications and hereditary protein S deficiency: 2 cases]. 876 59

High-dose estradiol therapy for reduction of final height may be complicated by severe side effects such as deep vein thrombosis. We report a 14.6-year-old girl with tall stature. In order to reduce final height she was treated with ethinylestradiol and medroxyprogesterone. After arthroscopy she suffered acute deep venous thrombosis of her left leg. Despite being monitored at short intervals, coagulation parameters such as AT III and protein C indicated no development of thrombosis. Medical height reduction with estrogen should be accompanied by heparinisation during longer-lasting periods of immobilisation.
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PMID:Severe thrombosis during treatment with ethinylestradiol for tall stature. 879 18

The diagnosis of thromboembolic diseases is still difficult to establish before the occurrence of the pathological event, although it is now known that they are the result of a progressive alteration of the cardiovascular system. Introduction of new diagnostic tools for the evaluation of the thromboresistance capacity of the body or for the measurement of molecular markers allows the testing of the body defenses against thrombosis which is becoming a routine clinical diagnosis. Antithrombin III (AT III), protein C, protein S, and parameters of fibrinolysis have been recognized to be very important anticoagulant proteins and regulators of thrombin formation and thrombus extension. Furthermore, a normal factor V is necessary for the normal function of the protein C pathway. The presence of a factor V mutation leads to the activated protein C resistance syndrome. However, the major incidence of thrombotic events concerns the overall population. It has been epidemiologically related to the existence of risk factors producing blood activation, which progressively saturates the body's thromboresistance. This period is clinically silent for a long time. The new molecular markers recently introduced can show the existence of a preclinical state of blood activation at the plasma level (fibrinopeptide A, thrombin-antithrombin complexes, modified antithrombin III, fragments 1 + 2 of prothrombin, D-dimer) or at the platelet level (B-thromboglobulin, platelet factor 4, and thrombospondin), and promising developments concern the endothelial level (soluble thrombomodulin). The most universally used blood activation test is the D-dimer assay. This analyte has become very popular in past years for its high sensitivity, its long half-life, and its easy detection directly on citrated plasma. Its negative predictive value (in deep venous thrombosis or pulmonary embolism) as well as its use for monitoring of thrombotic risk in the post-operative period have been well documented clinically. New investigations are initiated to find analytes reflecting endothelial damage, an early platelet activation, or the involvement of blood cells (mainly monocytes and neutrophils) in abnormal processes. It also becomes possible to evaluate directly pathological causes inducing blood activation, such as the presence of antiphospholipid antibodies or other autoimmune antibodies.
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PMID:Thromboembolic diseases: biochemical mechanisms and new possibilities of biological diagnosis. 880 28

The effect of oral contraceptive therapy was studied in five patients with homozygous activated protein C resistance. Patients with this congenital abnormality, in contrast to those with antithrombin, protein C or protein S deficiencies, showed only a mild thrombotic tendency. In fact, only two of six observations (one patient took the pill on two separate occasions many years apart) showed deep vein thrombosis. No patient had pulmonary embolism. Two additional patients had a superficial vein thrombosis of the legs. In two instances, a superficial vein thrombosis and a deep vein thrombosis, concomitant risk factors were present (immobilization and surgery for an ovarian cyst, respectively). However, compared with heterozygous for the same abnormality, the symptomatic homozygous patients with APC resistance appeared to develop thrombosis after a shorter period of oral contraception.
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PMID:Homozygous patients with APC resistance may remain paucisymptomatic or asymptomatic during oral contraception. 889 47

In a 6-month, randomized, double-blind study the effects of two combined oral contraceptives containing 150 micrograms desogestrel and either 20 or 30 micrograms ethinylestradiol on hemostatic parameters were investigated in 1633 healthy women. Compared with baseline, the 30 micrograms ethinylestradiol formulation increased prothrombin fragment 1 + 2 (+72.2%), D-dimer (+42.4%) and protein C activity (+6.1%), whereas antithrombin-III activity (-6.3%) and protein S activity (-19.7%) were decreased. The use of the 20 micrograms ethinylestradiol formulation was associated with the same pattern of changes, but with lower magnitude (F1+2 + 61.1%, D-dimer +36.0%, antithrombin III -5.3%, protein C +4.6% and protein S-16.0%). The changes from baseline were significantly smaller in the 20 micrograms ethinylestradiol group for D-dimer, antithrombin III and protein S than in the 30 micrograms ethinylestradiol group (p = 0.019, p = 0.038 and p = 0.001, respectively). One woman with a combined deficiency of proteins C and S developed deep venous thrombosis while using the 20 micrograms ethinylestradiol formulation. Use of both formulations was associated with a shift of the coagulation-fibrinolysis balance to an enhanced fibrin-generating and fibrin-degradating activity. The less-pronounced effect on hemostasis with the 20 micrograms ethinylestradiol preparation is reassuring with regard to thromboembolic risk in general. However, women with coagulation inhibitor deficiency should be advised not to use oral contraceptives.
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PMID:Ethinylestradiol 20 versus 30 micrograms combined with 150 micrograms desogestrel: a large comparative study of the effects of two low-dose oral contraceptives on the hemostatic system. 890 27

Resistance to activated protein C (APC resistance) was measured in 284 individuals (169 females, 115 males) with a history of objectively confirmed venous thrombosis and/or pulmonary embolism. A decreased APC resistance ratio was found in 75 patients (26%), 47 were females, 28 males. Factor V Leiden was investigated in 60 of 75 patients with APC resistance, of whom 46 were heterozygous, 4 homozygous. In 10 APC resistant patients the Arg 506 Glu mutation was not identified. The median age of the first thromboembolic event in patients with APC resistance was 42 years (range 15-82 years). Most patients had a history of deep vein thrombosis (83%), 28% had experienced pulmonary embolism. More unusual sites of thrombosis were the deep arm veins (7%) and mesenteric veins (one patient, 1.3%). 53% of patients developed the first thromboembolic event spontaneously. Precipitating conditions for thromboembolism were surgery in 9.3% and trauma in 8%. In one third of female patients the first thromboembolic event occurred in conjunction with pregnancy and delivery (14.8%) or oral contraceptives (19%). At the time of investigation 40% of patients with APC resistance had experienced recurrent thromboembolic events. The family history was positive in 60% of patients. We conclude that the clinical feature of APC resistance is similar to the feature of a deficiency of antithrombin, protein C and protein S. Pregnancy, delivery and oral contraceptives seem to be a relevant additional risk factors for thrombosis in females with APC resistance.
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PMID:Thrombotic tendency in 75 symptomatic, unrelated patients with APC resistance. 892 76

Both activated protein C (APC) resistance and protein C deficiency are associated with an increased risk for venous thrombosis. To assess their tendencies to venous thrombosis, we compared the median age of first venous thromboembolism in patients with factor V Leiden or protein C deficiency, who were identified either within unselected consecutive cases with a first deep venous thrombosis derived from a population-based case-control study, or identified by selection of patients with a deep venous thrombosis, who were referred for thrombophilIa work-up. The median age of onset for 92 unselected APC resistant cases was 43 years and for 13 unselected protein C-deficient cases 47 years. The median age at the first thrombotic event for 28 APC-resistant members of thrombophilia families was 29 years and for 50 protein C-deficient members of thrombophilia families 31.5 years. The median age of onset for all unselected patients (n = 105) was 45 years of age (range, 16 to 69 years) and the median age of onset for all selected patients from the thrombophilia families (n = 78) was 30.5 years (range, 16 to 67 years). These results show that within the case-control study and the family studies, the median age of onset is very similar in patients with APC resistance and patients with protein C deficiency. This suggests that APC resistance is not less severe with respect to risk of thrombosis than (heterozygous) protein C deficiency. In conclusion, the median age at which the first thrombosis occurs mainly depends on the way the patients are identified and not on the type of thrombophilia.
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PMID:Apparent different thrombotic tendency in patients with factor V Leiden and protein C deficiency due to selection of patients. 894 55

The clinical presentation of hereditary protein C deficiency is highly variable. Homozygosity and compound heterozygosity have been linked to severe thrombotic complications early in the life. Heterozygous patients have a moderate form of the disease with deep venous thrombosis during adulthood. In the French population, we found 53 different mutations in 90 families. The amount of the protein C produced by the mutant allele as well as the genetic status partly account for the variable clinical expression. Other gene may also be involved: Arg 506 to Gln factor V mutation shows a frequency of 10 to 20% in symptomatic protein C deficient patients. Some protein C gene mutations are associated with a non functional circulating protein; most of them are located in the GLA domain and in the serine protease domain. The biochemical characterization of a few of theses variants has shown the important role of some amino acids on the activation and the mechanism of action of protein C.
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PMID:Molecular basis for protein C hereditary deficiency. 897 7


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