Enzymes clinical uses

Humans are a far bigger threat to lizards than they are to us. Lizards are generally slow moving and nocturnal, with few enemies other than humans. The venom is a complex mixture that contains serotonin, a neurotransmitter, but lacks many of the other protein-degrading enzymes. Clinical effects are minor unless you are small and receive a large dose. 

The basic clinical tool used at the present time Is the competitive ligand binding assay for 25-OH-D. Although concentrations are low In the serum of patients with osteomalacia and v . tamln D deficiency rickets, we have recently noted the Interesting paradox that levels can be only 1/2 normal In the face of oyert bone disease (32). This had led us to propose that substrate levels of 25-OH-D3 available to the hydroxylase In kidney which Is responsible for the conversion of 25-OH-D3 to the tissue active metabolite, l,25(OH)2D3, may be rate limiting for this enzyme. 

Analytical Criteria for Clinical Enzyme Methods. The great variety of methods available for certain of the clinically useful enzymes can be confusing in the absence of criteria for assessing these methods. These criteria should be similar to those used to judge other quantitative clinical chemistry methods, and should also take into account the kinetic nature of the reaction. Some years ago, Amador and Wacker (17) suggested the following criteria, which are now widely us ... 

Clinical use Celecoxib (Graul et al., 1997 Wallace and Chin, 1999) is a second generation selective COX-2 inhibitor and the first drug of this group which reached the market. Its selectivity for COX-2 compared to COX-1 is about 375-fold greater in human recombinant enzyme preparations and about 8-fold in a whole blood assay. Celecoxib has been approved for rheumatoid arthritis, osteoarthritis, acute pain and primary dysmenorrhoea in the US and has been launched in an increasing number of countries since 1999. 

These reactions, which have provided a means of inhibiting the flavin-linked monoamine oxidases, enable us to end on a clinical note. The monoamine oxidases are responsible for the deamination of monoamines such as adrenaline, noradrenaline, dopamine, and serotonin, which act as neurotransmitters. Imbalances in the levels of monoamines cause various psychiatric and neurological disorders Parkinson s disease is associated with lowered levels of dopamine, and low levels of other monoamines are associated with depression. Inhibitors of monoamine oxidases may consequently be used to treat Parkinson s disease and depression. The flavin moiety is covalently bound to the enzyme by the thiol group of a cysteine residue (equation 9.17). The acetylenic suicide inhibitor N,N-dimethyl-propargylamine inactivates monoamine oxidases by alkylating the flavin on N-5.25 A likely mechanism for the reaction is the Michael addition of the N-5 of the reduced flavin to the acetylenic carbon 2... 

At a glance, the rapprochement between biochemistry and polymer chemistry seems to have played an important role in the methodological development of preparations for immobilized biocatalysts. A number of articles on the preparation and characterization of immobilized biocatalysts, together with their applications in a variety of fields besides synthetic chemical reactions - chemical and clinical analysis, medicine, and food processing, for example - have already been published. These results have been reviewed by many of the pioneers in this and related fields [1-20]. The technology for immobilizing enzymes and cells is believed to be relatively mature at this point. In addition, the nature of immobilized biocatalysts has become somewhat more transparent to us. The key now is to come up with new uses and new systems which can fulfill specific needs [21]. 

Worldwide, about 12 to 15 billion US per annum are spent for analytical purposes. Nearly 50 million US of this sum is devoted to enzymes. In clinical chemistry, several metabolites and their concentrations give important information about patients health (see Table 1). 

Between US 12 and 15 billion per year is spent worldwide for analytical purposes the portion used for enzymes amounts to about 50 million. Enzymes are being employed in clinical chemistry, the food and cosmetic industries, and biotechnology for the routine analysis of about 80 different substances, mainly low-molecular weight metabolites but also effectors, inhibitors, and the activity of enzymes themselves. 

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