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E S Barrow

Publications and source records attributed to E S Barrow.

10 recordsLinked to original sources
PubMed1979

The separation of Willebrand factor from factor VIII-related antigen.

The three activities associated with factor VIII--coagulant (VIII:C), antigenic (VIIIR:Ag), and platelet agglutinating or Willebrand factor (VIIIR:WF)--have been separated by sequential antibody affinity chromatography, utilizing a rabbit antibody to factor VIII and a spontaneous human antibody to VIII:C. Normal plasma differentially lost its factor VIII-related antigen following passage over the rabbit antibody column. Subsequent passage of the VIIIR:Ag-depleted plasma over the human antibody column resulted in the loss of VIII:C activity, with retention of the Willebrand factor activity, antigen being partially recovered from the heterologous antibody column. These experiments demonstrate that it is possible to separate two of the factor VIII activities, VIIIR:Ag and VIIIR:WF, which are usually regarded as properties of a single molecule.

Antibody Affinity↗
PubMed1978

Use of a simple visual assay of Willebrand factor for diagnosis and carrier identification.

A visual assay of factor VIII-related Willebrand factor (VIIIR:WF) is described which utilizes formaldehyde-fixed platelets, end points being read in microflocculation tiles. Four dilutions of a sample can be assessed simultaneously, and the correlation with aggregometric assays is high (r = 0.91). Measurement error is 8.0% for a single assay in triplicate and less than 5% if an assay is repeated three times. The method has been used for 2 years by the coagulation genetics group at Chapel Hill for diagnosing subjects with von Willebrand's disease and assigning genotypes to members of families transmitting this disorder. Its utility in classifying known carriers of haemophilia A has also been examined, both in conjunction with assays of VIII:C and in a three-way test with assays of VIII:C and VIIIR:Ag. As predicted by the Lyon hypothesis, the rate of false negative diagnosis was higher than false positive diagnosis, but the overall rate of misclassification on single plasma samples was 7/51 = 13.7%. The error rate was the same whether discrimination was based upon assays of VIII:C vs. VIIIR:Ag, VIII:C vs. VIIIR:WF, or VIII:C vs. VIIIR:Ag vs VIIIR:WF, the same individuals being misclassified by each method. The observed rate of misclassification was well within the rates reported by others and very similar to our previous experience. We have concluded that this method of assaying VIIIR:WF is highly useful for diagnosing vWd, detecting inhibitors to VIIIR:WF, and examining large numbers of column fractions. It is a useful supplement, although it cannot yet substitute for, assays of VIIIR:Ag in detecting carriers of haemophilia A.

Antigens↗
PubMed1975

Dominant inheritance of hemophilia A in three generations of women.

A bleeding diathesis is described which is phenotypically indistinguishable from hemophilia A and which has been transmitted as a dominant trait in three generations of women in a North Carolina kindred. The abnormal phenotype is characterized by clinical mildness and slightly abnormal clotting time, prothrombin consumption, and partial thromboplastin time. Bleeding time, platelet count, clot retraction, tourniquet test, and prothrombin time are normal. Concentration of factors I, II, V, VII, IX, X, and XII are normal, while factor VIII activity is reduced to 2%-5% of control values. De novo synthesis of factor VIII does not occur after transfusion; factor VIII-related antigen is normal; patients' plasmas aggregate platelets normally in the presence of ristocetin, and a typical protein pattern is seen when a chymotryptic digest of cryoprecipitate of the proband is examined by SDS-polyacrylamide gel electrophoresis. Six possible genetic explanations are entertained. Balanced X-autosomal translocation of hemophilia A heterozygotes has been excluded by cytogenetic analysis of metaphase chromosomes. Classes von Willebrand's disease (vWd) is probably excluded on the basis of the laboratory data, and extreme lyonization of hemophilia A heterozygotes on probabilistic grounds. The genetic possibilities which cannot be excluded include a previously unrecognized variant mutation at the vWd locus, a dominant mutation at the hemophilia A locus on the X chromosome, and dominant mutation at a hypothetical fourth locus involved in factor VIII synthesis and control.

Animals↗
PubMed1973

Factor VIII.

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Alleles↗