Metabolite distribution

Table 9.5 Metabolite distribution upon diclofenac hydroxylation with the MicroCyp Plate... 

Stoeckli M, Staab D, Schweitzer A. Compound and metabolite distribution measured by MALDI mass spectrometric imaging in whole-body tissue sections. Int. J. Mass Spectrom. 2006 260 195-202. 

Fig. 3 For the same run, insecticide plus metabolite distribution (percent) between the fish, plants and water.

Studies that address the site of production, the transport, and the deposition of secondary metabolites provide another level of resolution that needs to be considered when evaluating the function of secondary metabolites and their patterns of distribution. Unlike approaches that quantify an alga s total metabolite concentration, studies that localize metabolites contained within algal tissues provide evidence of more subtle changes in metabolite distribution in response to stimuli and may clarify metabolite function. 

The characterization of the metabolites also deserves the greatest care in order that chemotaxonomy remains a valid science. In particular, a close scrutiny of stereochemical relationships in a biosynthetic cascade may allow us to relate the metabolite distribution to lineages this is a task that genetics cannot yet perform (Guella 1997A). 

A potentially relevant association of 6-MP dosing and its metabolite distribution was suggested recently by data from the Pediatric Oncology Group 9605 trial (129). In this trial, daily 6-MP was compared with twice-daily administration during maintenance therapy of standard-risk childhood ALL. RBC 6-TGN and methylated metabolite levels were measured in a randomly selected subset of patients. 

The discussion and studies cited previously generally reflect overall tissue distribution of total arsenic after acute exposure in the case of laboratory animals or unknown exposures in the case of humans. Advances in analytical technology in the last decade have facilitated the identification of tissue-specific patterns of metabolite distribution and accumulation in laboratory animals. Kenyon, Del Razo and Hughes (2005a) found that inorganic arsenic was the predominant form of arsenic in the liver and kidney up to two hours post administration of 10 or 100 p mol As kg-1 as inorganic As(V) to female mice, whereas... 

Robitaille, P.M., Merkle, H., Sublet , E., Hendrich, K., Lew, B., Path, G., From, A.H.L., Bache, R.J., Garwood, M., Ugurbil, K. (1989). Spectroscopic imaging and spatial localization using adiabatic pulses and applications to detect transmural metabolite distribution in the canine heart. Magn. Reson. Med. 10,14-37. 

Dimitrov, S., Breton, R., MacDonald, D., Walker, J.D., and Mekenyan, O., Quantitative prediction of biodegradability, metabolite distribution and toxicity of stable metabolites, SAR QSAR Environ. Res., 13, 445 155, 2002. 

ADME Rapid entry through blood capillaries, distribution to many organs/tissues, metabolized to active and non-active metabolites Distribution limited based on size to plasma a/o extracellular fluid, degraded (catabolized) to endogenous amino acids... 

Reeburgh (1980) suggested that the pore-water distributions of SO and CH4 indicate that CH4 is being oxidized anaerobically with SO4 being the electron acceptor. This suggestion, which is virtually unavoidable based on the metabolite distributions and interpretation by diffusion equations (see also Murray et al., 1978), was not... 

In Vivo Applications. - 12.1.1 Sponges and Insects. Until now, direct, non-invasive in vivo studies on water and metabolite distribution in living sponges have not been possible. NMR imaging was applied for the first time to... 

Retention of individual PCB components from commercial mixtures depends upon species and organ, degree of chlorination, and substitution pattern (Hansen 1979,1987b). The metabolism of specific PCB congeners by different species is influenced by existing residues and can result in considerable variations in metabolite distribution (Hansen 1987b Safe 1989a) (see Section 3.4.3, Metabolism). Representative examples in various animal species are described below. 

The metabolism of specific PCB isomers by different species can result in considerable variations in metabolite distribution. 

Drug candidate metabolite distribution and disposition evaluations... 

Last but not the least, matrix-assisted laser-desorption ionization (MALDI) imaging mass spectrometry (IMS) caught a lot of attentions in the drug metabolism area. Drug distribution and individual metabolite distributions within... 

After an IV dose, streptozocin and its metabolites distribute mainly into the liver, kidneys, intestines, and pancreas. The drug has not been shown to cross the blood-brain barrier however, its metabolites achieve concentrations in the cerebrospinal fluid equivalent to the concentration in the plasma. 

Tannins are secondary metabolites distributed widely in the plant kingdom, which have been closely associated with plant defense mechanisms towards phytopathogens, insects and mammalian herbivores... 

In order to determine the metabolic fate of a radiolabeled drug, radioactivity in plasma, urine bile and feces is profiled for metabolite distribution. Metabolite profiling in muraglitazar study is described below. 

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