Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3.spsp.2 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg--Gly--Asp (RGD) adhesion sequence but containing K*--(G/Sar)--D wherein K* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: Defined constructs of modified human platelet-derived growth factor receptor polypeptides are provided. Extracellular region domain structures are identified and modifications and combinatorial rearrangements of the receptor segments are provided. Both cell bound and soluble forms of modified segments are made available, as are methods for assays using them, allowing for screening of ligand analogues.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K.sup.* -(G/Sar)-D wherein K.sup.* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C), phenyl or benzyl, or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: Platelet antiadhesives (PAA) which are useful as antithrombotics are obtainable from snake venoms which have been identified using an assay which measures the ability of the venom to inhibit ristocetin- or botrocetin-induced agglutination of platelets in the presence of von Willebrand Factor. The antiadhesives of the invention are 20-24 kd dimers of smaller peptides, or effective portions thereof. Antibodies to these antiadhesives are also prepared and are useful in assays for PAA and for screening expression libraries for PAA encoding DNA.

Abstract: A method for selectively inhibiting a kinase is disclosed, which comprises contacting a composition containing a kinase with a molecule of the formula ##STR1## wherein R.sub.1 is H, lower alkyl, or lower alkanoyl; R.sub.2 is H, lower alkyl, or lower alkanoyl; R.sub.3 and R.sub.4 together represent a cis double bond or --O-- or each of R.sub.3 and R.sub.4 independently represents H or OR; R.sub.5 is .dbd.O, .dbd.S, or --H, --OR; R.sub.6 and R.sub.7 together represent a double bond or --O-- or each of R.sub.6 and R.sub.7 independently represents H or OR; R.sub.8 and R.sub.9 together represent a double bond or --O-- or each of R.sub.8 and R.sub.9 independently represents H or OR; and each R independently represents H, lower alkyl, or lower alkanoyl.

Abstract: Analogs of Factor Xa (Factor Xai) which are inactive as proteases in the prothrombinase reaction are useful in treatment of diseases characterized by thrombosis. These antithrombotic agents can be conveniently prepared using recombinant techniques.

Abstract: Analogs of Factor Xa (Factor Xai) which are inactive as proteases in the prothrombinase reaction are useful in treatment of diseases characterized by thrombosis. These antithrombotic agents can be conveniently prepared using recombinant techniques.

Abstract: The DNA encoding the C140 cell surface receptor has been cloned and sequenced. The availability of this DNA permits the recombinant production of the C140 receptor which can be produced at cell or oocyte surfaces and is useful in assay systems both for the detection of substances which affect its activity, including agonists and antagonists. Further, the elucidation of the structure of the C140 receptor permits the design of agonist and antagonist compounds which are useful in these assays. The availability of the C140 receptor also permits production of antibodies specifically immunoreactive with the receptor per se or with specific regions thereof.

Abstract: A process for producing a highly purified preparation of an inhibited form of an activated blood factor entails providing a partially purified preparation containing the blood factor of interest, treating the partially purified preparation to convert the blood factor to an inhibited activated form in a single step, and then purifying the resulting inhibited activated blood factor.

Abstract: Analogs of Factor Xa (Factor Xai) which are inactive as proteases in the prothrombinase reaction are useful in treatment of diseases characterized by thrombosis. These antithrombotic agents can be conveniently prepared using recombinant techniques.

Abstract: A process for producing a highly purified preparation of an inhibited form of an activated blood factor entails providing a partially purified preparation containing the blood factor of interest, treating the partially purified preparation to convert the blood factor to an inhibited activated form in a single step, and then purifying the resulting inhibited activated blood factor.

Abstract: A process for producing a highly purified preparation of an inhibited form of an activated blood factor entails providing a partially purified preparation containing the blood factor of interest, treating the partially purified preparation to convert the blood factor to an inhibited activated form in a single step, and then purifying the resulting inhibited activated blood factor.

Abstract: Analogs of blood factors which are transiently inactive are useful in treatment of diseases characterized by thrombosis. In addition, modified forms of activated blood factors that generate the active blood factor in serum but have extended half-lives are useful in treating hemophilic conditions. These modified forms of the blood factor may be acylated forms which are slowly deacylated in vivo.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K*-(G/Sar)-D wherein K* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C) or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C.dbd.NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of the PAI in a wide range of snake venom samples were accomplished. The purified PAI from several of these active snake venoms is described. In addition, PAIs lacking the Arg-Gly-Asp adhesion sequence but containing Lys-Gly-Asp are prepared and shown to specifically inhibit the binding of fibrinogen or von Willebrand Factor to GP IIb-IIIa.

Abstract: Platelet antiadhesives (PAA) which are useful as antithrombotics are obtainable from snake venoms which have been identified using an assay which measures the ability of the venom to inhibit ristocetin- or botrocetin-induced agglutination of platelets in the presence of von Willebrand Factor. The antiadhesives of the invention are 20-24 kd dimers of smaller peptides, or effective portions thereof. Antibodies to these antiadhesives are also prepared and are useful in assays for PAA and for screening expression libraries for PAA encoding DNA.

Abstract: An assay for screening snake venom for the presence or absence of platelet aggregation inhibitors (PAIs) based on specific receptor binding is described. Using this assay, the identification and characterization of PAIs in a wide range of snake venom samples was accomplished. The isolated and purified PAI from several of these active snake venoms is described and characterized. In addition, PAIs lacking the Arg-Gly-Asp (RGD) adhesion sequence but containing K.sup.* -(G/Sar)-D wherein K.sup.* is a modified lysyl residue of the formulaR.sup.1.sub.2 N(CH.sub.2).sub.4 CHNHCO--wherein each R.sup.1 is independently H, alkyl(1-6C) or at most one R.sup.1 is R.sup.2 --C.dbd.NR.sup.3 wherein R.sup.2 is H, alkyl(1-6C) or is NR.sup.4.sub.2 in which each R.sup.4 is independently H or alkyl(1-6C) and R.sup.3 is H, alkyl(1-6C), phenyl or benzyl, or R.sup.2 --C=NR.sup.3 is a radical selected from the group consisting of: ##STR1## where m is an integer of 2-3, and each R.sup.