fibrinopeptide A

Fibrinopepide-A (FPA) is a peptide chain cleavage between sperm-16 and glycine-17 of fibrinogen α(A) chain under the action of thrombin, and is composed of 1 to 16 amino acids. Fibrin peptide A. It is a reliable indicator of the clotting activity in the body and the final formation of thrombus in fibrin. Increased plasma FPA levels reflect coagulation system activation and thrombin generation. Therefore, it is found in hypercoagulable state and thrombotic disease, identification of primary and secondary fibrinolysis, and monitoring indicators during anticoagulant therapy. Basic Information Specialist classification: growth and development examination classification: blood examination Applicable gender: whether men and women apply fasting: fasting Tips: Blood collection should not be >45s, and the first 2ml should be discarded. The syringe should be silicided or plastic syringe. Normal value 1.2 ± 0.8 μg / L. Clinical significance Increased plasma FPA levels reflect coagulation system activation and thrombin generation. Therefore, it is found in hypercoagulable state and thrombotic disease, identification of primary and secondary fibrinolysis, and monitoring indicators during anticoagulant therapy. High results may be diseases: disseminated intravascular coagulation in children, pregnancy with thrombotic disease, disseminated intravascular coagulation in the elderly (1) Blood collection should be smooth and should not be >45s, and the first 2ml should be discarded. The syringe should be silicided or plastic syringe. (2) Immediately after blood collection, inject into the test tube containing anticoagulant and mix it quickly in ice water. If it needs to be preserved, it is more suitable at -20 °C after adsorption treatment with bentonite. Inspection process (1) Collection of plasma specimens: 4.5 ml of venous blood was taken smoothly with a plastic syringe (the first 2 ml was discarded), and a test tube containing 0.5 ml of an anticoagulant (heparin sodium 500u and aprotinin 5000u) was added, and immediately mixed. Centrifuge at 3000 r/min for 20 min, separate the plasma, and draw the upper plasma to another tube for immediate treatment or storage at -20 °C. (2) Bentonite adsorption treatment of plasma samples: the purpose is to completely remove fibrinogen. 40 mg of bentonite was added to a 45 ml polypropylene plastic centrifuge tube, 0.5 ml of adsorption buffer was added, and the mixture was thoroughly mixed. 1 ml of plasma was added, shaken and mixed on a cyclone mixer, and shaken slowly for 10 min. Centrifuge at 5000r/min for 15min, aspirate the supernatant to another tube, and then treat it once with the bentonite as described above. Then, 1 ml of the supernatant was aspirated and added to a test tube containing 50 μl of a 20 g/LTween 20 solution, and mixed. The final specimen has been diluted 20 times. (3) FPA coating: 1 μg/ml of FPA was dissolved in coating buffer, polystyrene reaction plate was added, 200 μl/well, capped, and overnight at 37 °C. The hole was discarded the next day. The plate was washed 5 times with washing solution, 3 min each time, dried and spared. (4) FPA standard: 6 kinds of different concentrations such as 25, 12.5, 6.25, 3.12, 1.56, 0.78 ng/ml. 0.9 ml was separately aspirated into a series of small test tubes, and 0.1 ml of working concentration of rabbit anti-human FPA was added to each tube. The plasma samples to be tested by the bentonite adsorption treatment were operated as above, and the concentrations of 1:2, 1:4 times were as above. Each of the above tubes was reacted at 37 ° C for 3 h. (5) 200 μl of each of the above-mentioned tubes after the incubation was pipetted into each well of the coated FPA, and the plate was incubated at 37 ° C for 2 h, washed for 5 times, and dried. (6) Each well was added with HRP-goat anti-rabbit IgG (diluted to the working concentration by standard dilution) 200 μl/well, and the plate was incubated at 37 ° C for 2 h, washed for 5 times, and dried. (7) Add 200 μl of the freshly prepared substrate solution to each well, and accurately react at 37 ° C for 3 min in the dark, and immediately add 3 mol/L H 2 SO 450 μl to each well to terminate the reaction. The A value (492 nm) of each well was determined on the enzyme label. Not suitable for the crowd Hemophilia and diffuse intravascular coagulation. Adverse reactions and risks Risk of infection: If you use an unclean needle, you may be at risk of infection.