Blood coagulation activity

A proteolytic cascade occurs when one peptidase activates the next in a proteolytic pathway, and this in turn activates the next and so on. This is a mechanism to amplify the initial signal, because one peptidase molecule can activate many zymogen molecules. Examples of proteolytic cascades include blood coagulation, activation of digestive peptidases in the intestine, and apoptosis. 

Calcium has many important functions. It is involved in blood coagulation, activation of muscle phosphorylase, and secretory processes. It combines with phosphate to form the hydroxyapatite of bone. 

Ayres, N., Holt, D., Jones, C., Corum, L., Grainger, D. Polymer brushes containing sul-fonated sugar repeat units synthesis, characterization, and in vitro testing of blood coagulation activation. J. Polym. Sci., Part A Polym. Chem. 46(23), 7713-7724 (2008)... 

Griffin JH Role of surface in surface-dependent SO activation of Hageman factor (blood coagulation factor XII). Proc Natl Acad Sci USA 1978 75 1998-2002. 

Figure 51-1. The pathways of blood coagulation. The intrinsic and extrinsic pathways are indicated. The events depicted below factor Xa are designated the final common pathway, culminating in the formation of cross-linked fibrin. New observations (dotted arrow) include the finding that complexes of tissue factor and factor Vila activate not only factor X (in the classic extrinsic pathway) but also factor IX in the intrinsic pathway, in addition, thrombin and factor Xa feedback-activate at the two sites indicated (dashed arrows). (PK, prekallikrein HK, HMW kininogen PL, phospholipids.) (Reproduced, with permission, from Roberts HR, Lozier JN New perspectives on the coagulation cascade. Hosp Pract [Off Ed] 1992Jan 27 97.)...

MARCKMANN p, sandstrOm b, jespersen J (1990) Effect of total fat content and fatty acid composition in diet on factor Vll coagulant activity and blood lipids, Atherosclerosis, 80, 227-33. 

Edwards R. L., Rickies F. R. The role of leukocytes in the activation of blood coagulation. Semin Hematol 1992 29,202-12. 

The extrinsic mechanism of blood coagulation begins when a blood vessel is ruptured and the surrounding tissues are damaged. The traumatized tissue releases a complex of substances referred to as tissue thromboplastin. The tissue thromboplastin further complexes with factor VII and Ca++ ions to activate factor X directly. 

Volume 222. Proteolytic Enzymes in Coagulation, Fibrinolysis, and Complement Activation (Part A Mammalian Blood Coagulation Factors and Inhibitors)... 

The first aspect of biocompatibility is a natural immune response. When a foreign object enters the blood stream, it can be attacked by the body s defense system. The first step is protein adsorption on an object surface. It is believed that the amount and type of protein adsorption is one of the most important steps determining whether the object is tolerated or rejected by the body. The next step is cell adhesion, which may cause aggregation and activation of platelets and triggering of the blood coagulation system with resulting thrombus formation. It may not only lead to sensor failure via surface blocking but directly threatens the patient s health. 

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