Clinical enzymology

Affinity capture-release electrospray ionization mass spectrometry (ACESIMS) is another recently introduced technique for quantification of proteins, and to date has most often been applied to clinical enzymology.60 The product conjugates of the enzymatic reaction between the synthetic substrate and targeted enzyme are captured by immobilized affinity reagents, purified, released into solution, and analyzed by ESI-MS. 

A unit of enzyme catalytic activity equal to the conversion of one mole of substrate per second in a specified assay system. The katal (kat) is more commonly used in clinical enzymology. One unit of enzyme activity (i.e., one micromole per minute) corresponds to 16.67 nkat. 

Affinity capture-release electrospray ionization mass spectrometry (ACESIMS) and isotope-coded affinity tags (ICAT) are two recently introduced techniques for the quantitation of protein activity and content with applications to clinical enzymology... 

J. Biittner, Evolution of clinical enzymology ,./. Clin. Chem. Clin. Biochem., 1981,19, 529-538. 

Hoffman WE, Kramer J, Main AR, and Torres JL (1989) Clinical enzymology. In Loeb WE and Quimby FW (eds.) The Clinical Chemistry of Laboratory Animals, pp. 237-278. Philadelphia Taylor and Francis. 

J. King, Practical Clinical Enzymology, Van Nostrand, Princeton, NJ, 1965. 

Enzymes are proteins with catalytic properties clinical enzymology is the application of the science of enzymes to the diagnosis and treatment of disease. The principles of clinical enzymology will be mtroduced and discussed in this chapter. Individual topics include basic principles, enzyme kinetics, analytical enzymology, and diagnostic enzymology. 

When one of the substrates is water (i.e., when the process is one of hydrolysis), with the reaction taking place in aqueous solution, only a fraction of the total number of water molecules present participates in the reaction. The small change in the concentration of water has no effect on the rate of reaction and these pseudo-one substrate reactions are described by one-substi ate kinetics. More generally the concentrations of both substrates may be variable, and both may affect the rate of reaction. Among the bisubstrate reactions important in clinical enzymology are the reactions catalyzed by dehydrogenases, in which the second substrate is a specific coenzyme, such as the oxidized or reduced forms of nicotinamide adenine dinucleotide, (NADH), or nicotinamide adenine dinucleotide phosphate, (NADPH), and the amino-group transfers catalyzed by the aminotransferases. 

The choice and application of various methods of isoenzyme analysis in clinical enzymology are discussed in Chapter 21 in relation to specific isoenzyme systems. 

Panteghini M> Ceriotti F, Schumann G, Siekmann L. Establishing a reference system in clinical enzymology. Clin Chem Lab Med 2001 39 795-800. 

Methodological details for many of the muscle, liver, pancreatic, and bone methods discussed later in this chapter are found in a prior edition of this textbook (Moss DW, Henderson AR. Clinical enzymology. In Burtis CA, Ashwood ER eds. Textbook of clinical chemistry, 3 ed. WB Saunders Philadelphia, 1999 617-721.)... 

Principles of Clinical Enzymology Enzymes Enzymes Appendix... 

Bioluminescence is a unique type of chemiluminescence found in biological systems these reactions can be classified as either pyridine- or adenine-nucleotide linked systems or enzyme-substrate systems. In clinical enzymology, the most commonly used system is the firefly luciferin-luciferase system for the measurement of ATP ... 

R. B. McComb, A Universal Reference System for Clinical Enzymology, in A Reference System for Clinical Enzymology Proceedings of the Workshop (eds. G. N. Bowers, Jr., G. C. Edwards, and R. N. Rand), National Committee for Clinical Laboratory Standards, Villanova, 1986, p. 73. 

R. Rej and R. Vanderlinde, Use of Purified Enzyme Reference Materials in Enzyme Activity Measurements, in Proc. Second International Symposium on Clinical Enzymology (eds. N. W. Tietz and A. Weinstock), American Association for Clinical Chemistry, Washington, DC, 1976, p. 249. 

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