Enhanced metabolism

The most common unwanted effects of the barbiturates are oversedation and psychomotot impaitment, which may petsist well into the next day following a hypnotic dose. Patadoxical excitement, hypersensitivity reactions, and muscle or joint pain may occur in rare cases. Drug-drug interactions occur with the CNS sedatives, and a number of drugs have enhanced metabolism when co-administered with barbiturates (Barnhill et al. 1989). 

Resistance mechanisms associated with changes in toxicokinetics are predominately cases of enhanced metabolic detoxication. With readily biodegradable insecticides such as pyrethroids and carbamates, enhanced detoxication by P450-based monooxygenase is a common resistance mechanism (see Table 4.3). 

The question at this point was whether modifications could be made to the oxadiazole molecule to enhance metabolic stability and achieve comparable activity. This approach required knowledge of the site of metabolism and the nature of the metabolic products. This information was obtained from ion mass spectrometry. The identity of these products was determined by comparing the fragmentation pattern of metabolites A and B with the parent compound and the corresponding daughter ions (Fig. 25). 

A drug that specifically enhances metabolically the activity of brain dopamine is... 

The primary target for cyanide toxicity is the central nervous system following both acute and chronic exposure. Exposure to high doses of cyanide can rapidly lead to death (see Section 2.2). Cyanide is not stored in the organism and one available study indicates that >50% of the received dose can be eliminated within 24 hours (Okoh 1983). However, because of the rapid toxic action of cyanide, development of methods that would enhance metabolism and elimination of cyanide is warranted. 

Enhancing Metabolism. Metabolic enhancers theoretically work by promoting activity in relatively inactive areas of the brain. We can infer that these medications enhance brain activity by their ability to increase the brain s use of glucose and oxygen. The metabolic enhancers that have been tried to date include ergot alkaloids, nootropics, and vinca alkaloids. 

Patients with hyperthyroidism tend to have enhanced metabolism leading to weight loss, tremor and palpitations. Propranolol may be indicated to reduce the sympathetic symptoms, such as tremor and palpitations. 

G. Brix, M.E. Bellemann, L. Gerlach, U. Haberkom, Intra-and extracellularfluoroura-cil uptake Assessment with contrast-enhanced metabolic F-19 MR imaging. Radiology 209 (1998) 259-267. 

The deamino-dicarba-analogues of various biologically active cystine-containing peptides, such as oxytocin/1-3 calcitonin/31 32 and somatostatin/33-35 have shown high biological activity and enhanced metabolic and chemical stability owing to the absence of reducible disulfide linkages. 

Furthermore, the sulfonamide bond is expected to possess enhanced metabolic stability with structural similarities to the tetrahedral transition state involved in amide bond enzymatic hydrolysis, thus making sulfonamide peptides interesting candidates in the development of protease inhibitors and new drugs. The oligomers and polymers should also be interesting molecular scaffolds, with specific secondary structures enforced by hydrogen bonding)100,101 ... 

Enzymes with related functions often are compartmentalized into specific organelles, a process that enhances metabolic efficiency in various ways. First, the higher concentrations of enzymes and intermediates resulting from... 

In humans it has been demonstrated that increasing the ratio of protein to carbohydrate in the diet stimulates oxidation of antipyrine and theophylline, while changing the ratio of fat to carbohydrate had no effect. In related studies, humans fed charcoal-broiled beef (food high in polycyclic hydrocarbon content) for several days had significantly enhanced activities of CYPs 1A1 and 1A2, resulting in enhanced metabolism of phenacetin, theophylline, and antipyrine. Studies of this nature indicate that there is significant interindividual variability in these observed responses. 

Dabney et al. (2006) reviewed a variety of in-field, edge-of-held, and after-held buffers and noted four key principles (1) even narrow buffers improve water quality, (2) buffers work best on slow, shallow diffuse flows, (3) buffers slow, trap, and enhance metabolism of pesticides, and (4) buffers are most valuable on shallow soils, which are most susceptible to runoff. 

An acute dose of 100-200 mg morphine, or its equivalent, in the non-tolerant adult can lead to respiratory depression, coma and death. In the tolerant individual, single doses or more than 10 times this amount are tolerated and have little visible effect. The development of tolerance to the opiates does not appear to be due to enhanced metabolism (metabolic tolerance) but is probably due to opioid receptor insensitivity (tissue tolerance). The dependent person therefore ultimately requires high doses of the opiate to prevent withdrawal effects. 

Dinitrophenol enhances metabolism and has been applied as an agent For the treatment of obesity. Chronic dinitrophenol poisoning may cause liver and kidney damage. According to Lazarev [31], poisoning by dinitrophenol is characterized by the following symptoms general weakness, lack of appetite, rush of blood to... 

Two vicinal hydrogen atoms enhance metabolism greatly. 

Sato A, Nakajima T. 1985. Enhanced metabolism of volatile hydrocarbons in rat liver following food deprivation, restricted carbohydrate intake, and administration of ethanol, phenobarbital, polychlorinated biphenyl and 3-methylcholanthrene A comparative study. Xenobiotica 15 67-75. 

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