Biomaterial Database

An improved procedure for quantitation of platelet factor 4. 1977

A Saleem, and K Fretz

Platelet factor 4 (heparin neutralizing) activity shortens the thrombin time of a heparinized plasma. In the proposed procedure (I) a heparin thrombin time curve is constructed by adding gradually increasing amounts of heparin to a commercial plasma substrate and determining thrombin times, (2) a suitable concentration of heparin that gives highest reproducible thrombin time is selected and added to the substrate, (3) thrombin times are determined for the heparinized substrate before and after addition of a test material containing platelet factor 4. The two thrombin times are converted to heparin concentration by reference to the heparin thrombin time curve. The difference in heparin concentrations represents platelet factor 4 activity. When lyophilized commercial plasma is used as substrate larger quantities of heparin can be employed in the system, resulting in improved sensitivity and precision.

UI	MeSH Term	Description	Entries
D007202	Indicators and Reagents	Substances used for the detection, identification, analysis, etc. of chemical, biological, or pathologic processes or conditions. Indicators are substances that change in physical appearance, e.g., color, at or approaching the endpoint of a chemical titration, e.g., on the passage between acidity and alkalinity. Reagents are substances used for the detection or determination of another substance by chemical or microscopical means, especially analysis. Types of reagents are precipitants, solvents, oxidizers, reducers, fluxes, and colorimetric reagents. (From Grant & Hackh's Chemical Dictionary, 5th ed, p301, p499)	Indicator,Reagent,Reagents,Indicators,Reagents and Indicators
D010978	Platelet Factor 4	A CXC chemokine that is found in the alpha granules of PLATELETS. The protein has a molecular size of 7800 kDa and can occur as a monomer, a dimer or a tetramer depending upon its concentration in solution. Platelet factor 4 has a high affinity for HEPARIN and is often found complexed with GLYCOPROTEINS such as PROTEIN C.	Antiheparin Factor,CXCL4 Chemokine,Chemokine CXCL4,Heparin Neutralizing Protein,PF4 (Platelet Factor 4),gamma-Thromboglobulin,CXCL4, Chemokine,Chemokine, CXCL4,gamma Thromboglobulin
D001779	Blood Coagulation Factors	Endogenous substances, usually proteins, that are involved in the blood coagulation process.	Clotting Factor,Coagulation Factors,Blood Coagulation Factor,Clotting Factors,Coagulation Factor,Coagulation Factor, Blood,Coagulation Factors, Blood,Factor, Coagulation,Factors, Coagulation,Factor, Blood Coagulation,Factor, Clotting,Factors, Blood Coagulation,Factors, Clotting
D001780	Blood Coagulation Tests	Laboratory tests for evaluating the individual's clotting mechanism.	Coagulation Tests, Blood,Tests, Blood Coagulation,Blood Coagulation Test,Coagulation Test, Blood,Test, Blood Coagulation
D005069	Evaluation Studies as Topic	Works about studies that determine the effectiveness or value of processes, personnel, and equipment, or the material on conducting such studies.	Critique,Evaluation Indexes,Evaluation Methodology,Evaluation Report,Evaluation Research,Methodology, Evaluation,Pre-Post Tests,Qualitative Evaluation,Quantitative Evaluation,Theoretical Effectiveness,Use-Effectiveness,Critiques,Effectiveness, Theoretical,Evaluation Methodologies,Evaluation Reports,Evaluation, Qualitative,Evaluation, Quantitative,Evaluations, Qualitative,Evaluations, Quantitative,Indexes, Evaluation,Methodologies, Evaluation,Pre Post Tests,Pre-Post Test,Qualitative Evaluations,Quantitative Evaluations,Report, Evaluation,Reports, Evaluation,Research, Evaluation,Test, Pre-Post,Tests, Pre-Post,Use Effectiveness
D006493	Heparin	A highly acidic mucopolysaccharide formed of equal parts of sulfated D-glucosamine and D-glucuronic acid with sulfaminic bridges. The molecular weight ranges from six to twenty thousand. Heparin occurs in and is obtained from liver, lung, mast cells, etc., of vertebrates. Its function is unknown, but it is used to prevent blood clotting in vivo and vitro, in the form of many different salts.	Heparinic Acid,alpha-Heparin,Heparin Sodium,Liquaemin,Sodium Heparin,Unfractionated Heparin,Heparin, Sodium,Heparin, Unfractionated,alpha Heparin
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D013010	Sonication	The application of high intensity ultrasound to liquids.	Sonications
D013917	Thrombin	An enzyme formed from PROTHROMBIN that converts FIBRINOGEN to FIBRIN.	Thrombase,Thrombin JMI,Thrombin-JMI,Thrombinar,Thrombostat,alpha-Thrombin,beta,gamma-Thrombin,beta-Thrombin,gamma-Thrombin,JMI, Thrombin