81 research outputs found
Relationships between parameters used for routine quality monitoring of platelet concentrates
Multiple-laboratory comparison of in vitro assays utilized to characterize hematopoietic cells in cord blood
Retention of coagulation factors in plasma frozen after extended holding at 1-6 degrees C
Retention of coagulation factors in plasma frozen after extended holding at 1-6 degrees C
Background and Objectives: The ability to use plasma, isolated from units of whole blood and frozen within 24 h of phlebotomy, as a substitute for plasma frozen within 8 h of phlebotomy would have several advantages for blood centers. It should provide increased flexibility pertaining to the freezing of plasma for clinical use. We have conducted studies to assess the influence of an extended holding time for separated plasma, prior to freezing, on the retention of coagulation factor activity. Study Design and Methods: Freshly harvested plasma from each of 10 units of CPD-whole blood was divided into four equal aliquots. These aliquots were held in plastic packs at 1-6 degrees C for a total of 0, 8, 15 and 24 h. Subsequently, the plasma aliquots were frozen rapidly and stored at -20 degrees C for 4 months. The thawed plasma was tested for coagulant factors V and IX, factor VIII coagulant activity (factor VIII:C), von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor of von Willebrand factor. Results: The levels of factor V, factor vWF:Ag, factor IX and ristocetin cofactor were not influenced by holding the plasma for up to 24 h prior to freezing. Factor VIII:C activity was reduced with extended holding at 1-6 degrees C; the percentage at time zero activity was 75.9+/-2.4% for samples frozen immediately after a 24-hour period. Conclusions: The data indicate that coagulation factor properties of harvested plasma are retained except for factor VIII for at least 24 h prior to freezing. Copyright (C) 2000 S. Karger AG, Basel
Retention of coagulation factors in plasma frozen after extended holding at 1-6 degrees C
Background and Objectives: The ability to use plasma, isolated from units of whole blood and frozen within 24 h of phlebotomy, as a substitute for plasma frozen within 8 h of phlebotomy would have several advantages for blood centers. It should provide increased flexibility pertaining to the freezing of plasma for clinical use. We have conducted studies to assess the influence of an extended holding time for separated plasma, prior to freezing, on the retention of coagulation factor activity. Study Design and Methods: Freshly harvested plasma from each of 10 units of CPD-whole blood was divided into four equal aliquots. These aliquots were held in plastic packs at 1-6 degrees C for a total of 0, 8, 15 and 24 h. Subsequently, the plasma aliquots were frozen rapidly and stored at -20 degrees C for 4 months. The thawed plasma was tested for coagulant factors V and IX, factor VIII coagulant activity (factor VIII:C), von Willebrand factor antigen (vWF:Ag) and ristocetin cofactor of von Willebrand factor. Results: The levels of factor V, factor vWF:Ag, factor IX and ristocetin cofactor were not influenced by holding the plasma for up to 24 h prior to freezing. Factor VIII:C activity was reduced with extended holding at 1-6 degrees C; the percentage at time zero activity was 75.9+/-2.4% for samples frozen immediately after a 24-hour period. Conclusions: The data indicate that coagulation factor properties of harvested plasma are retained except for factor VIII for at least 24 h prior to freezing. Copyright (C) 2000 S. Karger AG, Basel.</p
Retention of coagulation factors in plasma frozen after extended holding at 1-6 degrees C
Irradiation of platelet components: inhibition of lymphocyte proliferation assessed by limiting-dilution analysis
Storage of aliquots of apheresis platelets for neonatal use in syringes with and without agitation
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