Isolation and characterization of the factor X Friuli variant.

Factor X Friuli was isolated from plasma by immunoaffinity and ion exchange chromatography and compared with normal factor X purified by the same method. Similar molecular weights were observed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the intact or activated factor X molecules including their respective heavy and light chains. These data indicated that there were no gross structural differences between the normal and variant proteins.

Brucellosis contracted during foreign travel.

Brucellosis, a bacterial infection, is rarely seen in the United States. It occurs mostly in people who work with domestic animals and animal products. However, this patient became infected while in Yugoslavia, and diagnosis was delayed by the gap between appearance of symptoms and positive results of serologic tests.

Resolution of monomeric and heterodimeric forms of tissue factor, the high-affinity cellular receptor for factor VII.

Tissue factor (TF) is the high affinity cell surface receptor and obligatory cofactor for plasma coagulation factor VII. Purification of TF from human brain and placenta has recently been reported to yield both a monomeric 47 kDa protein as well as a 58 kDa heterodimeric form. In this study, the TF glycoprotein was isolated from human brain by immunoaffinity chromatography using a newly developed monoclonal antibody, TF8-5G9, and was compared to TF isolated by factor VII-affinity chromatography.

Quantitation of human protein S in the plasma of normal and warfarin-treated individuals by radioimmunoassay.

Protein S was purified from human plasma and used to raise monospecific antibodies. A double antibody equilibrium radioimmunoassay was constructed and met all the requirements for a sensitive, accurate and specific determination of Protein S. The sensitivity of the assay was between 8-250 ng of Protein S/ml and the coefficient of variation was 2-6% within assays and 13-19% between assays.