Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0034065 (pulmonary embolism)
 14,979 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thrombomodulin (TM) is the anticoagulant endothelial cell membrane-bound protein cofactor in the thrombin-mediated activation of protein C (PC). It has been clearly demonstrated that the anticoagulant and profibrinolytic functions of the PC system are important for the prevention of a thromboembolic disease. Patients with PC, protein S, or PC "'cofactor"' deficiency and/or dysfunction develop thromboembolic diseases. However, the molecular abnormality in at least 20% to 30% of thrombophilic patients cannot be identified by hitherto recognized defects. A putative pathologic lesion in the TM gene could be one of several candidates for these prothrombotic mutations. A directed search strategy for deletions, insertions, or point mutations in the TM gene has not been performed. Therefore, in the present study, we have analyzed the entire TM gene, including the promoter region, by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) in normal healthy volunteers and in patients presenting with a thromboembolic disease. We have identified a patient with a thromboembolic disease and a TM point mutation. In a 45-year-old Hispanic man with a documented pulmonary embolism, PCR-SSCP showed an aberrant band pattern and subsequent DNA sequence analysis showed a heterozygous substitution for G1456 to T. This substitution predicts an Asp468 to a Tyr change in the amino acid sequence that is located between the transmembrane domain and the sixth epidermal growth factor-like domain. The Asp468 to Tyr change would probably lead to significant structural changes not allowing the expression of the TM protein or to a conformational change that is not functional.
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PMID:The first mutation identified in the thrombomodulin gene in a 45-year-old man presenting with thromboembolic disease. 781 89

A prospective, randomized, controlled clinical trial was performed comparing the antithrombotic efficacy of the low molecular weight heparin LMWH 21-23, (Braun) with an unfractionated heparin in elective general surgical patients over an observation period of 7 postoperative days. A total of 230 patients were admitted: 103 (group I) received low molecular weight heparin and 100 (group II) low-dose unfractionated heparin treatment given subcutaneously. In group I 41 patients (46%) were operated on for malignant disease and in group II 54 patients (54%). Due to the large amount of great abdominal procedures the intra- and perioperative application of hydroxyethyl starch was allowed for volume substitution. None of the patients died due to fatal pulmonary embolism. In group I four patients revealed positive 125I-labeled fibrinogen uptake (3.9%); two patients belonged to the hydroxyethyl starch subgroup. In group II five patients displayed a positive fibrinogen uptake (5%); two belonged to the hydroxyethyl starch subgroup. The results of the hemostaseological investigations (e.g., prothrombin time, activated partial thromboplastin time, thrombin clotting time, fibrinogen, antithrombin III, protein C, plasminogen, alpha 2-antiplasmin, tissue-type plasminogen activator, plasminogen activator inhibitor) revealed no statistically significant differences between groups I and II or their subgroups, although a tendency to prolonged clotting times was observed. The antifactor Xa activity values, however, displayed a statistically significant difference between the two groups (P < 0.05). The antifactor Xa activity measured up to 0.16 U/ml for the low molecular weight heparin (group I) and 0.05 U/ml for the unfractionated heparin (group II) in the postoperative period.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Prospective randomized clinical study in general surgery comparing a new low molecular weight heparin with unfractionated heparin in the prevention of thrombosis. 789 22

A young man with a history of deep vein thrombosis and pulmonary embolism 11 years ago presented again with acute pulmonary embolism and was treated initially with intravenous heparin at our institution. Five days later he had another massive bout of pulmonary embolism causing hypotension. Pulmonary angiography confirmed the presence of thrombi in both pulmonary arteries, with complete obstruction of the left pulmonary artery. He was treated successfully by emergency pulmonary embolectomy. Blood investigations later confirmed the diagnosis of protein S deficiency and he was started on warfarin therapy for life. Massive pulmonary embolism should be treated aggressively. Thrombolytic therapy accelerates clot lysis, reduces pulmonary pressures, restores pulmonary capillary volume and reverses right heart failure faster than heparin alone. There is also a trend towards decreased mortality with thrombolysis. In the presence of shock, the patient should be resuscitated and if facilities for emergency embolectomy are available, surgery is a viable alternative to thrombolysis, especially if the clot burden is massive. In young patients with recurrent venous thromboembolism in the absence of obvious predisposing factors, it is important to exclude inherited plasma protein deficiencies of protein S, protein C, antithrombin III, plasminogen and fibrinogen.
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PMID:Massive acute pulmonary embolism in protein S deficiency--a case report. 794 58

We studied 84 consecutive patients referred with the suspicion of pulmonary embolism (PE) to investigate the influence of clinical and hematological profiles on the diagnosis and severity of this disease and recovery. Diagnosis of PE was confirmed in 48 out of 84 patients by perfusion scintigraphy and/or pulmonary arteriography. Severity of PE and entity of recovery were investigated by measuring standard PaO2 on blood gas analysis and the number of unperfused lung segments ULS on perfusion scintigraphy. Most common clinical predisposing conditions were more frequent, though not significantly so, in embolic patients and a very low prevalence of PE was appreciable in patients without clear predisposing conditions. Among coagulation factors, only thrombin-antithrombin (TAT) complexes were twice as high in embolic as in nonembolic patients (14.0 +/- 13.6 vs. 7.0 +/- 4.2 ng/ml; p < 0.02), while there was no statistically significant difference between embolic and nonembolic patients for activated partial thromboplastin time, prothrombin time, antithrombin III, protein C, fibrinogen, plasminogen, alpha 2-plasmin inhibitor, and plasminogen activator inhibitor-1. Sensitivity and specificity of TAT complexes in diagnosis of PE were 95.8% and 30.5%, respectively. Therefore, normal values of TAT complexes may help exclude the diagnosis of PE, while abnormal values allow to reinforce the clinical suspicion of PE. No relation was found between coagulation parameters and the severity of PE. The follow-up of 48 patients with confirmed PE was favorable on the average; however, neither the presence of predisposing conditions nor abnormal coagulation parameters allow to predict the degree of functional and scintigraphic improvement during follow-up.
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PMID:Clinical, anamnestic and coagulation data in patients with suspected or confirmed pulmonary embolism. 800 95

A dysfunctional protein C (PC) molecule (Protein C Padua 2) was found in a 40-year-old man presenting with recurrent deep vein thrombosis/pulmonary embolism and a family history of thrombotic disease. The patient exhibited a normal PC antigen level, normal chromogenic activity (using Protac as PC activator) but markedly reduced coagulometric activity. After adsorption of patient plasma onto Al(OH)3, between 30% and 45% PC antigen/chromogenic activity but no coagulometric activity was detectable in the supernatant. The dysfunctional molecule exhibited reduced affinity for a Ca++ dependent anti-protein C monoclonal antibody as detected by specific ELISA assay. Immunoblotting experiments showed that PC Padua 2 had an increased MW (95 kD v 65 kD for normal PC). The lesion responsible was determined by PCR/direct sequencing to be a heterozygous CGT/TGT transition in exon 3 of the protein C gene resulting in the substitution of Arg by Cys at residue--1 in the pro-peptide leader sequence. The presence of a high MW PC was consistent with the fact that (part of) the propeptide (at least Cys-1) still was attached to the protein C molecule. This finding could also explain the strongly reduced affinity of PC Padua 2 for the Ca++ dependent anti-protein C monoclonals.
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PMID:A novel dysfunctional protein C (protein C Padua 2) associated with a thrombotic tendency: substitution of Cys for Arg-1 results in a strongly reduced affinity for binding of Ca++. 813 74

This study of 49 patients with spontaneous venous and arterial thrombosis identified 27 with hypercoagulable states: 13 had only venous thrombosis (VT), six had episodes of VT followed by arterial thrombosis (AT) and eight had AT only. All 27 patients were less than 42 years of age; 22 had specific natural anticoagulant or fibrinolytic deficiencies: antithrombin III (nine patients), protein C (eight patients), protein S (three patients), heparin cofactor II (two patients), tissue plasminogen activator release (one patient) and mixed antithrombin III and protein S (one patient). The remaining five patients had recurrent thrombotic events associated with resistance to heparin anticoagulation, but no established laboratory diagnosis. Clotting complications included recurrent VT, pulmonary embolism, multiple failed arterial procedures and lower extremity amputation. The remaining 22 patients (mean age of 53 years, range of 46 to 63 years), 12 with VT and ten with AT, did not have laboratory evidence of hypercoagulability and none had recurrent vascular occlusions. All these patients were successfully treated by conventional therapy without any additional thrombotic events during the follow-up period. Young adults with spontaneous thrombotic events should be screened for possible hypercoagulable states. Additionally, these young patients need further evaluation and treatment of cardiovascular risk factors. Those with premature atherosclerosis have an especially poor prognosis despite surgical intervention and anticoagulant therapy.
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PMID:Hypercoagulable states as an evolving risk for spontaneous venous and arterial thrombosis. 792 7

From November 1987 to February 1992, extracorporeal life support (ECLS) was used for four patients undergoing prolonged external cardiac massage following cardiac arrest. Their underlying diseases consisted of acute pulmonary embolism, pulmonary arterial thrombosis due to protein C deficiency, acute inferior left ventricular infarction accompanied by right ventricular infarction and thoracic contusion. After the initiation of ECLS, hemodynamic variables and metabolic acidosis improved in all of the cases. The case of pulmonary embolism and the case of acute myocardial infarction were successfully weaned from ECLS without complications. They were later discharged ambulatory from the hospital. The patient with pulmonary arterial thrombosis, who was comatose, became alert after the initiation of ECLS. However the patient finally died due to diffuse and massive pulmonary arterial thrombosis, which was probably related to protein C deficiency. The patient with thoracic contusion was also comatose before ECLS. He did not recover from the coma and died soon after the disconnection of ECLS. The latter two cases were suspected to have had irreversible organ failures not responsive to mechanical support of both circulation and respiration. We conclude that ECLS is a very useful method for patients requiring prolonged cardiac massage following cardiac arrest.
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PMID:Extracorporeal life support for patients undergoing prolonged external cardiac massage. 844 87

Plasma levels of selected coagulation and fibrinolytic parameters (activated partial thromboplastin time, prothrombin time, fibrinogen, antithrombin III, protein C, thrombin-anti-thrombin III complexes (TAT), plasminogen activator inhibitor-1 (PAI-1), plasminogen, alpha 2-plasmin inhibitor) were evaluated in 90 patients with clinical suspicion of pulmonary embolism (PE). Plasma levels of fibrinogen, PAI-1 and TAT were significantly higher in patients than in controls (p < 0.01): evaluation of TAT displayed a sensitivity of 96.1% and specificity of 30.8%, and positive and negative predictive values of 64.5 and 85.7%, respectively. The number of nonperfused lung segments correlated directly with TAT levels (p < 0.01) and inversely with arterial pO2 values (p < 0.01). No significant difference was found in the other parameters between patients and controls. Our results suggest that the finding of normal TAT plasma levels can help to exclude PE in patients with clinically suspected PE.
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PMID:Thrombin-antithrombin III complexes as an additional diagnostic aid in pulmonary embolism. 869 74

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

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


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