Rate of metabolic degradation

Jl, J4, T6). Little benefit can be demonstrated at lower plasma levels. In one study adjustment of dosage to maintain steady-state plasma theophylline levels within a recommended optimum therapeutic range of 10-20 /ig/ml led to improved therapeutic control (J4). To achieve this a more than 8-fold difference in the daily dose was necessary (J4), due to variations between one subject and another in the rate of metabolic degradation of theophylline. 

The method is widely used nowadays for the synthesis of 13-amino acids. Peptides that contain P-amino acids feature a lower rate of metabolic degradation and are therefore of interest for pharmaceutical applications. 

Individual polymorphisms in some of the P450 isozyme genes likely would alter the rates of metabolic degradation (or conversely activation) or particular clinical drugs. 

Enhanced biorestoration is a means by which naturally occurring processes are deliberately manipulated to increase or enhance the rate of cleanup. Biological activity in the subsurface is controlled by the availability of one or more of the necessary metabolic requirements such as an electron acceptor or nutrient. Although electron acceptors are most often the limiting factor, inadequate availability of nitrogen, phosphorus, or micronutrients (such as potassium, copper, or even vitamins) can restrict optimum restoration. When the proper balance of these factors is established, the rate of chemical degradation is maximized. 

In long-term evolutionary scales, humans now have the abilities to intervene rapidly in this interdependent relationship and alter the stability of the rates of metabolism of organic matter. For example, reduction of ozone in the stratosphere and associated increased UV irradiance could lead to accelerated photolytic degradation of macromolecules of DOM by both abiotic and biotic pathways to C02. In addition, the photolytic enhancement of substrates for bacterial metabolism by UV photolysis can result in accelerated rates of biogeochemical cycling of nutrients and stimulated... 

The rate and extent of pesticide metabolism can vary dramatically, depending on chemical stmcture, the number of specific pesticide-degrading microoiganisms present and their affinity for the pesticide, and environmental parameters. The extent of metabolism can vary from relatively minor transformations which do not significandy alter the chemical or toxicological properties of the pesticide, to mineralization, ie, degradation to CO2, H2O, NH, Q, etc. The rate of metabolism can vary from extremely slow (half-life of years) to rapid (half-life of days). 

From a medical point of view, it should be noted that a healthy human tissue does not contain bacteria utilizing PHB. But experiments [23] have suggested a difference between the rate of hydrolytic degradation in vivo and in vitro. The interpretation is that enzymes from the body itself catalyze the hydrolytic degradation process in vivo. During the degradation, PHB molecules decompose into 3HB. It is found in human blood and can be metabolized by the body. 

Nutritional and hormonal conditions also affect the rate of protein degradation, whereby nutritionally deprived cells degrade protein more rapidly as a means of supplying nutrients for critical metabolic processes. Interestingly, increased degradation rates are countered by antibiotics, but which may act to block protein synthesis at the same time. The possibility is therefore inferred that antibiotics may not only block the degradation of cancer cells, but their formation as well. 

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