ABSTRACT
Vascular arteriovenous malformations originate during the early stages of embryonic development and generally grow progressively, especially during adolescence and pregnancy. Limb salvage using microsurgery is presented, in a patient with an arteriovenous malformation who was initially a candidate for limb amputation. En bloc resection of the arteriovenous malformation of all segments with extended brachial approach and the cutaneous component was performed, with an anterolateral thigh free flap for the lateral reconstruction of the hand.
Subject(s)
Arteriovenous Malformations/surgery , Free Tissue Flaps/surgery , Hand Deformities, Congenital/surgery , Limb Salvage/methods , Thigh/surgery , Adolescent , Arteriovenous Malformations/diagnostic imaging , Female , Free Tissue Flaps/blood supply , Hand/blood supply , Hand/diagnostic imaging , Hand/surgery , Hand Deformities, Congenital/diagnostic imaging , Humans , Microsurgery/methods , Thigh/blood supplyABSTRACT
Concanavalin A interacts specifically with the oligosaccharides from protein-C and modifies its anticoagulant activity. The lectin activates the protein-C activity in a dose dependent manner as demonstrated by in vitro and in vivo assays. Concanavalin A at low concentration (0.1 to 2 microg/mL) induces an increase on the catalytic activity of protein-C; at higher concentrations (5 to 20 microg/mL), the catalytic activity returns to the baseline. The effect of concanavalin A was prevented by incubating the protein-C with alpha-methyl-mannoside or by treating the purified protein-C with alpha-mannosidase; furthermore, cleavage of mannosidic residues diminishes its catalytic activity. Our results indicate that the oligomannosidic portion of protein-C participates in the regulation of the catalytic activity of this protein.
Subject(s)
Concanavalin A/pharmacology , Protein C/metabolism , Animals , Catalysis/drug effects , Concanavalin A/adverse effects , Concanavalin A/antagonists & inhibitors , Concanavalin A/metabolism , Dose-Response Relationship, Drug , Female , Fibrin/biosynthesis , Humans , Lectins/pharmacology , Mannosidases/metabolism , Methylmannosides/pharmacology , Mice , Mice, Inbred BALB C , Oligosaccharides/metabolism , Partial Thromboplastin Time , Protein C/isolation & purification , Thrombin Time , alpha-MannosidaseABSTRACT
We have developed a rapid, efficient, and inexpensive method to purify protein C from plasma using Concanavalin A conjugated to Sepharose. With this method we have obtained protein C purified to homogeneity, as measured in polyacrylamide gels. We discuss each of the steps of our method and give the results of the purification.
