The nucleotide and deduced amino acid sequences of the encephalomyocarditis viral polyprotein coding region.

The nucleotide sequence of 7200 bases of encephalomyocarditis (EMC) viral RNA, including the complete polyprotein-coding region, was determined. The polyprotein is encoded within a unique translational reading frame, 6870 bases in length. Protein synthesis begins with the sequence Met-Ala-Thr, and ends with the sequence Leu-Phe-Trp, 126 bases from the 3' end of the RNA.

Subunit composition of oligomeric human von Willebrand factor.

The oligomerization of human endothelial cell-synthesized von Willebrand factor (vWf) has been studied by gel chromatography in columns of Sephacryl S-500 and by discontinuous agarose gel electrophoresis. A quantitative recovery of high Mr vWf oligomers has been obtained after binding to a monoclonal anti-vWf-Sepharose adduct. This reagent has been used to analyze gel filtration chromatographic elution profiles of [35S]methionine-labeled culture medium and cell lysate.

Biosynthesis of the subunits of factor VIIIR by bovine aortic endothelial cells.

The biosynthesis of the subunit of factor VIIIR was studied in bovine aortic endothelial cells by the techniques of immunoprecipitation and NaDodSO4/polyacrylamide gel electrophoresis. It was determined that the subunit is first produced as a Mr 240,000 glycoprotein precursor, which appears to undergo proteolytic cleavage at or about the time of secretion into the medium with a resultant change in apparent Mr to 225,000, the size of the mature subunit found in plasma. The Mr 240,000 species was detected within 10 min of the start of labeling of cells, but factor VIIIR was not detected in the culture medium until approximately equal to 50 min.

The binding of bovine factor XII to kaolin.

Purified bovine factor XII was radiolabeled with iodine-125 and its binding to kaolin studied. Binding was rapid and was not readily reversible upon adding unlabeled factor XII. The optimum pH for binding was in the region of pH 5-7.

Factor VIII-induced superaggregation of human platelets.

High concentrations of bovine factor VIII cause clumping of platelets into a few very large aggregates. This response is termed superaggregation. It is distinct from factor-VIII-induced agglutination but is also independent of both extracellular calcium ions and platelet energy metabolism.

The agglutination of human platelets by bovine factor VIII: R.

The binding of bovine factor VIII: R to human platelets causes an agglutination of the platelets and subsequent responses that may serve as a model for the interaction of platelets with damaged vascular subendothelium. Purified bovine factor VIII: R was radiolabeled and its binding to formalin-fixed human platelets measured. Binding was rapid and readily reversible.

Kinetic analysis of bovine factor VIII in the hemophilic dog.

Bovine factor VIII, which did not contain platelet aggregating factor activity, was infused into hemophilic dogs. Factor VIII procoagulant (VIII:C) levels in the dogs increased dramatically, then decreased in a biphasic manner. The half-life of the longest component was 3-7 hrs.

Characterization of a form of bovine factor VIII which does not aggregate human platelets.

Fractionation of partially purified bovine factor VIII on tricalcium citrate columns produces a material which contains high levels of factor VIII procoagulant activity and factor VIII-related antigen, but does not aggregate human platelets. The procoagulant activity can be blocked by human inhibitors of factor VIII: C and by rabbit antibody to bovine factor VIII. Its activity can be increased by thrombin modification.

Clinical blood chemistry values and long acting phenothiazines.

Fifty-nine chronic schizophrenic patients received one year of treatment with either fluphenazine enanthate or pipothiazine palmitate IM. Both long acting neuroleptics significantly decreased serum albumin, total protein and creatinine values. Triglycerides were decreased only early in treatment.

Effect of surfaces on fluid-phase prekallikrein activation.

The activation of prekallikrein by factor XII fragments (XIIf), during incubation in plastic tubes was previously noted to be increased by high molecular weight (HMW) kininogen as well as other plasma proteins. In this report, we investigated the mechanism responsible for this increase. Although we confirmed that HMW kininogen, bovine serum albumin, fibrinogen, cold insoluble globulin, and mixed phospholipids apparently increased prekallikrein activation, we found that the product of prekallikrein activation (kallikrein) lost substantial activity in less than 0.

A rapid quantitative staphylococcal co-agglutination assay. Utilization for the assay of bovine factor VIII-related antigen.

A simple and rapid technique to measure bovine factor VIII-related antigen has been developed which utilizes protein A-bearing staphylococci and monospecific rabbit antiserum to bovine factor VIII. Staphylococci coated with a specific antibody agglutinate when they are mixed with the specific antigen. We have used an aggregometer to detect an quantitate the agglutination of the antibody-coated staphylococci.

Thrombocytin, a serine protease from Bothrops atrox venom. 2. Interaction with platelets and plasma-clotting factors.

Thrombocytin, a serine protease from Bothrops atrox venom, caused platelet aggregation and release of platelet constituents at a concentration of 10(-7) M and clot retraction at a concentration of 2 x 10(-9) M. Thrombocytin was slightly more active when tested on platelets in plasma than on washed platelets suspended in Tyrode--albumin solution. Thrombin was 5 times more active than thrombocytin when tested on platelets in plasma and 50 times more active when tested on washed platelets.

Thrombocytin, a serine protease from Bothrops atrox venom. 1. Purification and characterization of the enzyme.

Thrombocytin, a platelet-activating enzyme from Bothrops atrox venom, has been purified to homogeneity by precipitation with sodium salicylate and chromatography on heparin--agarose. Thrombocytin is a single-chain glycoprotein with a molecular weight of 36 000 which contains 5.6% carbohydrate.

Prekallikrein activation by Hageman factor: potentiation by proteins in the absence of high molecular weight kininogen.

Proteins which potentiate the conversion of prekallikrein to kallikrein by Hageman factor fragments are present in cryoprecipitate prepared from the plasma of an individual lacking HMW kininogen as well as in purified von Willebrand's factor preparations. However, the potentiator activity could be separated from the von Willebrand's antigen and ristocetin cofactor activity by chromatography on QAE-Sephadex. Moreover, it was present in plasma from an individual lacking von Willebrand's factor.

Synthesis of cold-insoluble globulin by cultured calf endothelial cells.

Radiolabeled amino acids were incorporated into nondialyzable protein by cultures of endothelial cells derived from calf aorta. Antibody prepared against purified bovine plasma cold-insoluble globulin (CIG) formed a strong precipitin line upon immunodiffusion against 3H-labeled proteins from endothelial cell culture media. This precipitin line formed a line of identity with the precipitin line formed by anti-CIG and purified CIG.

Cell wall formation in zoospores of Allomyces arbuscula. III. Carbohydrate composition of cell walls during development from meiospores to hyphae.

Carbohydrate composition was determined in isolated cell walls of meiospores of Allomyces arbuscula after incubation for 15 min (encysted meiospores: cysts), 150 min (germlings: cysts + rhizoids) and 24 h (cysts + rhizoids + hyphae). The principal constituent in all cell wall samples is chitin, accounting for about 75% of the recovered carbohydrates. In addition, cell walls of all stages examined contain polysaccharides which release galactose, glucose, mannose, arabinose, xylose, fucose, and rhamnose on acid hydrolysis.

Cell wall formation in zoospores of Allomyces arbuscula. II. Development of surface structure of encysted haploid zoospores, rhizoids, and hyphae.

Development of haploid meiospores of Allomyces arbuscula into germling cells with rhizoids and hyphae was followed during incubation in complete growth medium. The surface structure of encysted meiospores, rhizoids and hyphae before and after extraction of amorphous materials with ethanolic KOH was studied by means of carbon-platinum replicas. After 2--3 min incubation in complete medium 10% of the meiospores were surrounded by a cell wall containing microfibrils embedded in a matrix.

Evans blue: a specific inhibitor of factor VIII-induced platelet agglutination.

Low concentrations of Evans Blue (less than 1 muM) inhibit the agglutination of formalin-treated platelets by bovine Factor VIII or by human Factor VIII in the presence of the antibiotic ristocetin. Evans Blue is a specific inhibitor of this reaction and acts by inhibiting the binding of Factor VIII to the platelet surface.