non-protein components of enzymes whose activity would not exist without their presence. Cofactors are generally stable to heat whereas most enzyme proteins lose activity on heating. See enzymes. cosmaceuticals -- the term used to describe cosmetics containing ingredients that are bioactive, exerting effects on people. "High-performance" cosmetics where the active ingredients are bioactive and/or the formulation uses new delivery system technology. The name is derived from combining cosmetics and pharmaceuticals.
1. Substances, microorganisms, or characteristics of individuals that may influence the progression of a disease or the likelihood of becoming ill. 2. A substance, such as a metallic ion or coenzyme, that must be associated with an enzyme for the enzyme to function. 3. A situation or activity that may increase a person's susceptibility to AIDS. Examples of cofactors are: other infections, drug and alcohol use, poor nutrition, genetic factors, and stress. In HIV immunology, the concept of cofactors is being expanded and new cofactors have been identified. A recent example is the discovery of the interaction of CXCR4 (fusin) and CD4 to facilitate entry of HIV into cells.