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)

Hepatitis-B-surface antigen (HBsAg) was not detected by sensitive radioimmunoassays in the tear fluids of 6 HBsAg carriers with low and medium titers of HBsAg (less than 1:10,000) in the serum. However, HBsAg could be demonstrated in low concentrations in tear fluids of 5 of 6 HBsAg carriers with high serum titers (greater than 1:10,000). The concentration of HBsAg in the tear fluid was at least 100 times lower than in the sera of these 5 persons. Correspondingly HBsAg could be found in only 1 of the rinsing and in none of the storage solutions of the contact lenses of 7 persons with high titers of HBsAg in the serum (greater than 1:32,000). HBsAg was not adsorbed to smooth HEMA-lenses. Because of the low concentration of HBsAg in tear fluids and the dilution effect (about 5 x 10(-10)) the transmission of hepatitis B by multiple use of contact lenses by several persons during adaption is lighly unlikely. In addition, a special cleaning solution (Liprofin) can destroy nearly completely the antigenicity of HBsAg at 60 degrees C.
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PMID:[Detection of HBsAg and HBeAg in cleaning, rinsing and storage solutions of contact lenses and in tear fluid of carriers of HBsAg (author's transl)]. 54 19

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

Manufacturers are attempting to increase the purity of FVIII concentrates. A strategy pursued by some is that of including a purification step (gel filtration, ion-exchange or affinity chromatography) that yields concentrates with an intermediate or final specific activity of 35 to 250 IU FVIII/mg of protein. The specific activity of the final product may be lower because serum albumin is added to some concentrates to stabilize FVIII. In hemophiliacs treated with these concentrates, FVIII recovery and half-life are at least as good as those for less pure concentrates. In patients with von Willebrand disease, these concentrates increase plasma levels of FVIII, but their capacity to normalize the bleeding time is not well established. The hypothesis that their reduced alloantigen load might slow the progression of human immunodeficiency virus (HIV) infection is still not validated, but a few prospective studies are now attempting to address this issue. All the concentrates undergo virucidal procedures based on pasteurization or treatment with solvent/detergent. It is well established that these virucidal methods and donor screening avoid HIV transmission. A recent large study has shown that a pasteurized concentrate carries a low risk of transmitting viral hepatitis. The assessment of safety from hepatitis of concentrates treated with solvent/detergent is based on favorable preliminary results.
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PMID:High-purity factor VIII concentrates produced without using monoclonal antibodies. 212 70

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

The enormous progress made in biotechnology and purification of plasma proteins (pp) and the demands to avoid risks of transmitting HIV, hepatitis and other virus infections by these have resulted in the development of numerous recombinant human (rh) pp, which are now about to be used as replacement therapy in transfusion medicine. Human rh albumin has been used in clinical trials last year, a competition to serum albumin can be expected in the next time. During the last decade, the genes or cDNA have been cloned and characterized for all relevant pp involved in blood coagulation. Beside the rh factor VIII (rh FVIII) which has been introduced clinically in 1991, the rh FVIIa is under investigation in patients with hemophilia A and inhibitors. After establishing of rhFIX in triple transgenic mice, the industrial potential will be evaluated in terms of scale up culturing and production. The valuation of advantages and drawbacks of the current rh pp in comparison to conventional pp will have to be determined in the last decade of our century.
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PMID:[Recombinant plasma proteins for therapeutic use--status and developmental trends]. 769 61

Hemophilia B is an X-linked genetic disorder that typically results from chronic circulating deficiency of blood coagulation factor IX (FIX) (1). While the occurrence of hemophilia B is significantly less frequent than hemophilia A (factor VIII, deficiency) it has received special attention as a model for gene therapy. This is because hemophilia B is one of the least complicated genetic diseases from the point of view of demonstrating the proof of principle of a gene therapy protocol. Specifically, hemophilia B is a single gene recessive disorder and a wide range of tissues can be targeted for FIX gene delivery and strict regulation of FIX expression is not required. In addition, the 2.8 kb FIX cDNA is much smaller than the 9 kb FVIII cDNA, and FIX expression in transfected mammalian cells has been less problematic than FVIII expression (2). Since clinical severity of bleeding episodes closely corresponds to a patient's FIX activity, achieving even partial restoration of normal FIX levels in the bloodstream can alleviate internal bleeding. Individuals with FIX levels less than 1% of normal experience severe symptomatic episodes but providing roughly 5% of normal levels (i.e., 250 ng/mL plasma) can significantly reduce the frequency and severity of bleeding episodes and reduce long term complications (3). Treatment of hemophilia B primarily relies on intravenous injections of FIX protein purified from pooled human plasma, or very recently, on newly developed recombinant FIX. Treatment is applied typically only when bleeding episodes have occurred or are expected, for example, in case of a trauma or surgery. Although the risk of viral transmission of HIV and hepatitis viruses has been largely eliminated the absolute safety of any product derived from blood cannot be guaranteed. Furthermore, supplies of factor concentrates are limited and costs (especially if prophylactic treatment is being considered) are high. Thus, the application of gene therapy to hemophilia, whereby long-term correction of factor IX deficiency might be achieved, would be extremely useful.
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PMID:Ex Vivo Stromal Cell Electroporation of Factor IX cDNA for Treatment of Hemophilia B. 2144 54

Acquired haemophilia A, secondary to systemic lupus erythematosus (SLE) is a rare bleeding diathesis. Here we report a 37-year-old woman with autoimmune hepatitis who developed SLE and acquired haemophilia caused by factor VIII inhibitors. She presented with spontaneous ecchymosis and haematuria. There were a prolongation of the activated partial thromboplastin time, reduced factor VIII activity and a high titer of FVIII inhibitors. Therapeutic regimen was started with intravenous methylprednisolone pulse, continued with prednisolone, intravenous pulse cyclophosphamide and fresh frozen plasma. After 8 weeks, factor VIII inhibitor assay was negative.
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PMID:Acquired haemophilia A in a woman with autoimmune hepatitis and systemic lupus erythematosus; review of literature. 2202 58


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