Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0684275 (haemophilia)
 10,958 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abnormal factor IX variant proteins were isolated from the plasmas of three unrelated severe hemophilia-B families that had been previously shown to contain functionally impaired molecules immunologically similar to normal factor IX. The families studied were: (1) a patient with markedly prolonged ox brain prothrombin time, designated factor IX Bm Lake Elsinore (IXBmLE); (b) three patients (brothers) with moderately prolonged ox brain prothrombin time, designated factor IX Long Beach (IXLB); and (c) a patient with normal ox brain prothrombin time designated factor IX Los Angeles (IXLA). Each variant molecule comigrates with normal factor IX (IXN) both in the sodium dodecyl sulfate and in the nondenaturing alkaline gel electrophoresis. All three variant proteins are indistinguishable from IXN in their amino acid compositions, isoelectric points, carbohydrate distributions and number of gamma-carboxyglutamic acid residues. Each variant protein undergoes a similar pattern of cleavage by factor XIa/Ca2+ and by factor VIIa/Ca2+/tissue factor, and is activated at a rate similar to that observed for IXN. All of the three variant proteins also react with an anti-IXN monoclonal antibody that interferes with the binding of activated IXN(IXaN) to thrombin-treated factor VIIIC. However, in contrast to IXaN, the cleaved IXBmLE has negligible activity (approximately 0.2%), and cleaved forms of IXLA and IXLB have significantly reduced activity (approximately 5-6%) in binding to antithrombin-III/heparin, and in activating factor VII (plus Ca2+ and phospholipid) or factor X (plus Ca2+ and phospholipid) +/- factor VIII. These data, taken together, strongly indicate that the defect in these three variant proteins resides near or within the latent catalytic site. This results in virtually a complete loss of catalytic activity of the cleaved IXBmLE molecule and approximately 95% loss of catalytic activity of the cleaved IXLA and IXLB molecules.
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PMID:Characterization of three abnormal factor IX variants (Bm Lake Elsinore, Long Beach, and Los Angeles) of hemophilia-B. Evidence for defects affecting the latent catalytic site. 396 13

Nine partial thromboplastin (cephalin) reagents have been compared in a parallel investigation of groups of patients on ;long-term' anticoagulants, a group with moderate haemophilia, and patients on heparin infusion. Results with the seven commercial reagents and a human cephalin extract have been correlated with those of a specially prepared and standardized reference preparation of human brain origin. The comparison was similar in principle to that of the prothrombin time thromboplastin standardization using the British Comparative Thromboplastin (BCT). Results, which for comparative purposes were expressed as ratio of patients' cephalin times to control cephalin times, varied greatly in all three groups. In the oral anticoagulant group some of the commercial reagents were particularly insensitive to the ;intrinsic' clotting defect. The correlation between the ;standardized preparation' and the other reagents was not good and the use of a reference cephalin material for quality control of cephalin time tests does not appear promising. In moderate haemophilia the commercial reagents were either relatively poor at picking out the clotting defect compared with the ;standardized preparation' or gave such a bad endpoint that the results were not dependable. The poor endpoint also limited the dependability of the results of all but the ;standardized preparation' and two of the commercial reagents in controlling heparin administration. In view of these standardization difficulties, which cannot apparently be resolved by the use of reference material, there is need for bulk, routine supplies of a sensitive, standardized cephalin reagent giving good reproducible endpoints. The method for the provision of such material in a recently introduced national supply scheme is described.
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PMID:The partial thromboplastin (cephalin) time test. 465 57

Three patients with Christmas disease whose plasma was shown to have a prolonged one-stage prothrombin time with ox brain thromboplastin have been investigated. These patients have an inhibitor for the reaction between factor X, factor VII, and ox brain extract. The abnormal constituent responsible for this inhibitor appears to be factor IX whuch is functionally inactive but antigenically indistinguishable from normal factor IX. It is proposed that patients might be classified into haemophilia B(+) for patients with this defect (Christmas disease(+)) and haemophilia B(-) (Christmas disease(-)) for patients who have classical Christmas disease.
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PMID:An investigation of three patients with Christmas disease due to an abnormal type of factor IX. 497 71

Factor IX activity (IX:C) and antigern (IX:Ag) as well as factor VII, prothrombin time, Normotest and Thrombotest were determined in 37 haemophiliacs B from 26 kindreds, in 30 carriers of haemophilia B and in 40 healthy subjects. In 15 obligatory carriers from 9 kindreds, in which haemophiliacs did not exhibit IX:Ag in excess of IX:C, IX:C was parallel with IX:Ag, but in 4 from 4 kindreds, in which haemophiliacs exhibit excess of IX:Ag, there was a discrepancy between IX:C and IX:Ag. Among the obligatory carriers 6 from 3 kindreds, in which haemophiliacs did not have IX:Ag in excess of IX:C, showed that the anomaly M is not a sign of genetic variability of haemophilia B.
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PMID:Characterization of heterogeneity of haemophilia B for the detection of carriers. 615 11

On the basis of the indirectly established statement that activated forms of the coagulation factor are also present in PPSB fractions of own production, the activated concentrate of factor IX and of the prothrombin complex were applied in haemophilia-A patients with antibodies against factor VIII. The fraction was administered to 4 patients during 14 bleeding times, mostly during bleedings of joints an soft tissues, twice during haematuria in a dose of 40-200 E-factor IX per kg of body weight and per day. The total dose was mainly administered in a fractionized way at an interval of 8 or 12 hours. This treatment lasted for 2 to 7 days. With regard to haemostasis no fundamental improvement of global blood coagulation tests (which have pathological results in haemophilia-A patients) could be identified in the course of the treatment. However, the increase of factor II, VII, and X in the patient's plasma was striking. Contrary to exceptations, there was a less distinct increase of factor IX activity. Concluding from these findings it may be assumed that the "strengthening" of the "extrinsic system" is decisive for the haemostatic effect in the treatment mentioned.
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PMID:[Importance of PPSB fraction in the treatment of hemophilia A with antibodies against factor VIII]. 616 35

Disturbances of haemostasis caused immunologically and non-immunologically were observed after transfusion of blood and blood derivatives. Transfusion of heparin blood increased the bleeding susceptibility only in case of pre-existing high-degree defects of haemostasis or if they were performed as massive or exchange transfusions. Massive transfusions with blood stored for a long time will induce complex defects. Under intensive substitution therapy of haemophilia A the so-called paradoxical bleeding will occur in spite of a high factor VIII level. These bleedings are supposed to be disturbances of the thrombocyte function and are caused by fibrin(ogen) derivatives. Post-transfusional thrombocytopenias may be brought to remission by repeated plasmapheresis. Factor specific inhibitory bodies will appear after substitution in a small percentage of haemophilic patients. 5 to 7 days after the onset of therapy an anamnestic reaction can be observed as a titre increase by leaps. Usually, the inhibitory titre will decrease to a mostly low basal value in the course of three to five months. The therapy with cyclophosphamide simultaneously started with the substitution will more frequently prevent the anamnestic reaction or reduce it. Titres with more than 5 units cannot be overcome at the beginning even by higher concentrations of preparations. The substitution therapy should be preceded by exchange transfusions or plasmapheresis of up to 25 units. With still higher titres only procedures of inhibitor-bypassing are possible with factor VIII preparations of animal origin or better with activated prothrombin complex preparations, such as FEIBA. Recent reports give evidence that permanent substitution with factor VIII concentrates at a highest dosage can eliminate the production of inhibitors completely.
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PMID:[Hemostasis disorders after transfusions]. 616 96

T-cell immunity and serum levels of thymosin alpha 1, beta 2-microglobulin, circulating immune complexes, serum immunoglobulin levels, antibodies to hepatitis surface or core antigen, and to cytomegalovirus, and Epstein-Barr virus were investigated in 51 patients with haemophilia A ranging in age from 2 to 52 years. All patients had received commercial U.S. lyophilized concentrates of antihaemophilic factor (AHF). The mean helper/cytotoxic-suppressor (OKT4/OKT8) ratio of 11 pre-adolescents (1.6 +/- 0.4 SE) was not significantly different from that of age matched normal controls. In contrast, the mean OKT4/OKT8 ratios of 13 adolescent (1.2 +/- 0.2 SE) and 23 adult (0.8 +/- 0.1 SE) haemophiliacs were significantly reduced. Abnormalities of lymphocyte mitogenic responses were found only in adult haemophiliacs. Nine individuals treated with commercial U.S. prothrombin complex concentrates for antibodies directed against AHF or for haemophilia B had normal mean OKT4/OKT8 values. The mean serum thymosin alpha 1 levels for each age category was similar to that of age matched controls; however, regression analysis revealed a significant relationship between elevated thymosin alpha 1 levels and decreased OKT4/OKT8 ratios in adult haemophiliacs (P = 0.012). Although the mean serum level of beta 2-microglobulin was significantly increased in the adult haemophiliac group, there was no correlation between OKT4/OKT8 ratios and any of the other serologic parameters studied.
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PMID:Inverse correlation between age related abnormalities of T-cell immunity and circulating thymosin alpha 1 levels in haemophilia A. 623 39

A sensitive solid phase enzyme immunoassay (EIA) was developed for the measurement of factor IX antigen (IX:AG), using rabbit antihuman factor IX antiserum and beta-D-galactosidase, which enabled us to detect IX:AG as low as 10(-4)U/ml. 37 patients with severe hemophilia B have been investigated by EIA, inhibitor neutralization assay and bovine brain prothrombin time. They could be divided into four genetic variants. 25% had normal levels of IX:AG but decreased levels of factor IX clotting activity. On crossed immunoelectrophoresis of the hemophilia B+ and hemophilia BM, we could not find abnormalities in electrophoretic mobilities compared to normal subjects in the presence of 1 mM Ca++ lactate.
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PMID:Sensitive solid phase enzyme immunoassay for factor IX antigen and classification of hemophilia B. 634 Nov 81

It is reported on a 19-year-old patient with haemophilia A, in whom after a tooth extraction haemorrhages developed which could not be commanded. Factor-VIII-inhibitors could be proved qualitatively and quantitatively. As prospective for the therapy proved to be the administration of activated prothrombin complex preparations (FEIBA). The haemorrhages stopped, the partial thromboplastin time shortened. After three weeks the patient could be dismissed from hospital treatment.
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PMID:[The problem of factor VIII inhibitors in patients with congenital coagulopathies]. 640 20

This paper describes a successful cardiac operation in a young boy with hemophilia, congenital heart disease, severe factor VIII deficiency, and an acquired high titer antibody to factor VIII. To our knowledge, there have been no published cases of elective cardiac operations in a person with severe hemophilia and an accompanying complex problem. Utilizing the team approach, we administered a megadose bolus of factor VIII concentrate preoperatively (eight times the calculated dose), followed by a continuous intravenous infusion at 500 units/hr throughout the procedure and at a reduced dose for the first 5 postoperative days. With the anamnestic rise in factor VIII antibody on day 5, activated prothrombin complex concentrates were substituted for factor VIII and provided continued adequate hemostasis during the remaining 9 postoperative days. The rapid infusion of large quantities of factor VIII was effective in neutralizing the low titer inhibitor and providing normal hemostasis during the procedure. In addition, activated prothrombin complex concentrates were substituted for factor VIII coagulant without recurrent bleeding or thromboembolic phenomena.
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PMID:Elective cardiac operation in a patient with severe hemophilia and acquired factor VIII antibodies. 642 12


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