Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We recently observed a increase in factor-VIII clot promoting activity as measured by a one-stage assay (VIII AHF) in a haemophiliac with hepatitis. However, VIII AHF as measured by a two-stage assay (VIII AHF) was 0.013 u/ml at a time when VIII AHF measured 0.38 u/ml. We then studied seven non-haemophiliacs with liver disease, and attempted to correlate the lvels of VIII AHF and VIII AHF with factor VIII-like antigen (VIII AGN) as measured by quantitative immunoelectrophoresis. In four of the seven patients, disproportionate elevations of VIII AHF compared to VIII AHF were found. Furthermore, VIII AHF values correlated well with VIII AGN vales . No such discrepancy was apparent in four normal control subjects. These findings emphasize the necessity for performing two-stage assays in haemophiliacs as well as non-haemophiliacs with liver disease to assess factor-VIII levels. In addition, they suggest that confirmation of the diagnosis of haemophilia may not be possible in the haemophiliac with hepatitis unless VIII AHF determinations are performed. The reason for the disparity between VIII ahf and VIII AHF levels is not apparent. However, the correlation of VIII AGN and VIII AHF levels in the non-haemophiliacs with liver disease provides further support for the concept that VIII AGN and VIII AHF are closely related or identical molecular entities.
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PMID:Relationship of factor VIII-like antigen (VIII AGN) and clot promoting acitivty (VIII AHF) as measured by one- and two-stage assays in patients with liver disease. 99 Jan 95

Porcine or bovine factor VIII concentrates (FVIII:C) have been used during the past 3 decades to control bleeding in patients who have developed antibodies to human factor VIII. Since current preparations of animal FVIII:C are not known to transmit infectious agents such as hepatitis or human immunodeficiency virus, they are of potential therapeutic interest. A purified porcine FVIII:C (Hyate:C) is now widely used as an alternative to human FVIII:C in patients with inhibitor. Unlike earlier preparations of porcine FVIII:C, thrombocytopaenia is rare with the current preparation. Nonetheless, it causes the aggregation of human platelets in vitro. Our aim was to identify precisely the plasma factor which induces platelet aggregation. The effects of commercial porcine FVIII:C, porcine fibrinogen, porcine fibronectin and the corresponding preparations from human origin on platelet aggregation were studied. Platelet aggregation was quantified by measuring the fall in single platelet count in human whole blood. Of these preparations, only porcine FVIII:C (0.1-1 U/ml) and porcine fibrinogen (80-600 micrograms/ml) induced a fall in single platelet count of up to 85% due to aggregation. The extent of aggregation was directly proportional to the amount (0.007-0.1 U/ml test aliquot) of residual von Willebrand factor antigen (vWf:Ag) in the preparations. A monoclonal antibody to vWf:Ag inhibited the aggregation. We believe that the aggregation of human platelets induced in vitro by porcine FVIII:C is mediated by vWf:Ag which also may be responsible for thrombocytopaenia reported following administration of porcine FVIII:C in vivo.
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PMID:Further evidence that the residual vWf:Ag in porcine FVIII:C induces human platelet aggregation. 212 38

Heating sterilized albumin preparations at 600 degrees C for 10 hours has historically been shown to yield a hepatitis-free, efficacious product. We have evaluated such a pasteurization procedure with AHF preparations. Procoagulant activity and fibrinogen stability were dependent on the amount of sucrose used as a stabilizer. Flash pasteurization at 72 degrees C was evaluated and was found to be detrimental to AHF. Effect of sucrose concentration was shown on the inactivation kinetics of porcine parvovirus. In the absence of other stabilizers, increased sucrose can provide increased thermoresistance to the virus in 2.5% albumin.
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PMID:Pasteurization of antihemophilic factor and model virus inactivation studies. 393 Dec 93

The work presents results of the investigations of blood derivatives--F VIII concentrates: commercial cryoprecipitate, concentrate of intermediary purity and derivatives of high purity: Kriobulin--Immuno, Octobulin--Landerlan, Profilate--Alfa, Factor VIII--Behring, Hemofil--Hyland, Factorate--Armour Pharma, AHF--Kaote Cutter. The following parameters were investigated: VIII: C, VIIIR: Ag, total protein, protein electrophoresis, IgG, IgA and IgM immunoglobulins and anti-A and anti-B isoagglutinins. All derivatives except cyroprecipitate have considerably higher VIIIR: RAg value compared with VIII: C, which indicated inactivation of labile VIII: C component during concentrate preparation. Specific activity varied depending on purity of preparations, but ranged from 1,72 to 22. High isoagglutinin titer of anti-A was noted in preparations of high purity, as well as the presence of immunoglobulins. Despite considerable differences in vitro, all concentrated derivatives F VIII have similar immediate clinical effect and recovery from 0,87 to 1,36. All results indicate that new ways of derivative F VIII purification should be found with lower degree of contamination of other plasma proteins and less risk of hepatitis virus transmission. When certain indications are recognized, cryoprecipitate produced in our country in all blood transfusion services should be used.
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PMID:[Comparative study of concentrated blood derivatives of factor VIII]. 644 67

Plasma derivatives can be separated into those with either a low or a high risk of transmitting viral hepatitis. Low-risk products, with few exceptions, will remain low-risk irrespective of the plasma from which they are manufactured because they are heated at 60 degrees C for 10 hours (Albumin, Plasma Protein Fraction) or because they contain protective antibodies (Immune Globulin). This would appear to be the case not only for hepatitis B but also for non-A, non-B hepatitis. The risk of hepatitis B associated with plasma derivatives is reduced but not eliminated by HBsAg screening of donors. Further decreasing the risk of hepatitis B associated with AHF or Factor IX lots, as well as newer products like AT-III, alpha-1 antitrypsin, Fibronectin, C-1 Inactivator, and Factor XIII, may be accomplished either by the combination of stabilization and heating or by assuring that these products contain an excess of anti-HBS. For highly-purified products with little residual immunoglobulin it may be necessary to add anti-HBs. The addition of antibodies against non-A, non-B hepatitis agents when they are identified, could prevent transmission of both forms of viral hepatitis by plasma derivatives. Methods to stabilize and heat high-risk plasma derivatives to inactivate hepatitis viruses have the potential to remove both hepatitis B and non-A, non-B hepatitis infectivity.
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PMID:Plasma derivatives and viral hepatitis. 681 45