cofactor

(redirected from ristocetin cofactor)
Also found in: Dictionary, Thesaurus, Encyclopedia.
Related to ristocetin cofactor: mixing study

cofactor

 [ko´fak-ter]
an element or principle, e.g., a coenzyme, with which another must unite in order to function.
heparin cofactor II a member of the serpin group that inhibits thrombin.

co·fac·tor

(kō'fak'ter, tōr),
1. Synonym(s): coenzyme
2. An atom or molecule essential for the action of a large molecule, for example, heme in hemoglobin, magnesium in chlorophyll. Solo metal ions are regarded as cofactors for proteins, but not as coenzymes.

cofactor

(kō′făk′tər)
n.
1. One of two or more contributing factors.
2. A substance, such as a metallic ion or coenzyme, that must be associated with an enzyme for the enzyme to function.

co·fac·tor

(kō'fak'tŏr)
1. Synonym(s): coenzyme.
2. An atom or molecule essential for the action of a large molecule; e.g., heme in hemoglobin, magnesium in chlorophyll.

cofactor

a substance that is essential for the catalytic activity of some enzymes, binding to the enzyme only during the reaction. Cofactors can be metallic ions, or nonprotein organic molecules (coenzymes) such as vitamins in the B-COMPLEX.

co·fac·tor

(kō'fak'tŏr)
An atom or molecule essential for the action of a large molecule.
References in periodicals archive ?
Common VWF exon 28 polymorphism in African Americans affecting the VWF activity assay by ristocetin cofactor. Blood 2010; 116: 280286.
Comparison of von Willebrand factor (VWF) activity VWF::Ac with VWF ristocetin cofactor activity VWF:RCo.
prolonged bleeding after superficial lacerations 13 16 Female Epistaxis, 54.50 12.00 years prolonged bleeding alter superficial lacerations, prolonged bleeding alter tooth extraction 14 17 Male Epistaxis 77)90 23.00 years Patients Col/Epi(s) Col/ADP(s) 1 205 170 2 120 86 3 152 98 4 177 84 5 143 63 6 105 84 7 101 76 8 156 109 9 229 134 10 134 96 11 131 75 12 136 89 13 234 119 14 135 80 Col/ADP: collagen/adenosine diphosphate, Col/Epi: collagen/ epinephrine, vWF:Ag: von Willebrand factor antigen, vWF:RCo: ristocetin cofactor activity.
Without vWD With vWD(n=14) P (n=26) vWF antigen (%) 111.21[+ or 89.89[+ or -]25.38 0.012 -]23.97 vWF:RCo (%) 84.92[+ or 28.39[+ or -]12.82 0.000 -]26.39 PFA-100 (Col/Epi) 125.42[+ or 154.14[+ or 0.016 (s) -]29.30 -]42.30 PFA-100 (Col/ADP) 75.69[+ or 97.36[+ or -]28.03 0.013 (s) -]8.41 vWF: von Willebrand factor, vWF:RCo: ristocetin cofactor activity, With vWD: symptomatic children with von Willebrand disease, Without vWD: symptomatic children without vWD.
(2) Nonstandard abbreviations: VWD, von Willebrand disease; VWF:RCo, von Willebrand factor ristocetin cofactor activity; VWF:Ag, von Willebrand factor antigen level; PT-VWD, platelet VWD.
Common VWF exon 28 polymorphisms in African Americans affecting the VWF activity assay by ristocetin cofactor. Blood 2010;116:280-6.
Tests for von Willebrand factor antigen and von Willebrand factor ristocetin cofactor showed normal values, thereby excluding von Willebrand disease.
[4] Nonstandard abbreviations: vWF, von Willebrand factor; vWD, von Wille brand disease; DDAVP, 1-deamino-[8-D-arginine]-vasopressin; vWF:Ag, vWF antigen; vWF:RCof, ristocetin cofactor activity; vWF:CB, collagen-binding assay; FCS, fluorescence correlation spectroscopy; TRITC, tetramethyl-rhodamine isothiocyanate.
Use of collagen binding assay for von Willebrand factor in the analysis of type 2M von Willebrand disease: a comparison with the ristocetin cofactor assay.
Ristocetin cofactor activity by BCS analyzer [Package Insert].
The ristocetin cofactor is a test to assess VWF activity.