Disease relevance of Models, Chemical

• Isoniazid (INH) is easily oxidized with manganese(III) pyrophosphate, a chemical model of the KatG protein involved in activation of INH inside the bacteria Mycobacterium tuberculosis [1].
• As a result of these studies, a chemical model has been proposed to explain the oxidative deterioration of proteins in nutritional muscular dystrophy due to vitamin E deficiency [2].
• Release rates were found to fit well with the chemical model and several conjugates of camptothecin and one of combretastatin were shown to have potent cytotoxic effects on cultures of human neuroblastoma IMR-32 cells which over-express somatostatin receptors [3].

High impact information on Models, Chemical

• Base (O.-2, e-, or OH-)-induced autoxygenation of organic substrates: a model chemical system for cytochrome P-450-catalyzed monoxygenation and dehydrogenation by dioxygen [4].
• Herein, we investigated the possible cocarcinogenic potential of high and, in particular, low insulin levels, combining this in vivo model with a chemical model of hepatocarcinogenesis after administration of N-nitrosomorpholine (NNM) [5].
• Chemical model studies using 3-methyl-2-buten-1-ol and 3-methyl-3-buten-1-ol (the alcohols corresponding to dimethylallyl pyrophosphate and isopentenyl pyrophosphate, respectively) confirm this hypothesis [6].
• This is a chemical model for the enzymic reaction of CoA transferase [7].
• Studies on chemical models derived from reaction between acrolein and cysteine also supported this suggestion [8].

Biological context of Models, Chemical

• A chemical model for the cyclization step in the biosynthesis of L-myo-inositol 1-phosphate [9].
• The peroxidase-catalyzed decomposition of 3-hydroperoxy-1-butene (1), 2,3-dimethyl-3-hydroperoxy-1-butene (2), tert-butyl hydroperoxide (3), ethyl oleate hydroperoxide 4, and linoleic acid hydroperoxide 5 was applied as a chemical model system to assess whether lipid hydroperoxides may cause DNA damage under peroxidase catalysis [10].
• The chemical model system was therefore used on a microscale to react AFB1 with plasmid pHR1800, a plasmid containing the genes for beta-lactamase (amp-r) and galactokinase (galK) [11].
• 1. A sensitive method to detect and quantify the products of phenobarbital (PB) hydroxylation by model chemical systems and by biological systems has been developed [12].
• Biomimetic oxidation of 2-methylimidazole derivative with a chemical model system for cytochrome P-450 [13].

Anatomical context of Models, Chemical

• Here we have developed chemical model systems to investigate the interactions of silver sulfadiazine and silver chloride in direct contact with synthetic serum electrolyte solution (SSES), with SSES plus endogenous ligands or beef blood plasma, and with human serum [14].
• There may be additional roles for P450 since rates of formaldehyde production by microsomes exceed rates found with model chemical systems [15].
• The usefulness of the micronucleus test using supravital staining of peripheral blood reticulocytes with acridine orange was evaluated in two laboratories after administering cyclophosphamide (CYP) as a model chemical by intraperitoneal injection (i.p.) to CD-1 mice [16].

Associations of Models, Chemical with chemical compounds

• The chemical models used comprise about 70 atoms and include the first-shell ligands, two histidines, one glutamate, and one water, as well as some second-shell ligands, two histidines, one aspartate, and one tyrosine [17].
• Ring scission of diastereomeric 4-butylspiropentylcarbinyl radicals as a chemical model for identifying enzyme-catalyzed FAD adducts resulting from spiropentylacetyl-CoA [18].
• Trapping of an activated HF molecule inside a double four-ring unit: a quantum chemical model of the microporous fluorinated gallium phosphate ULM-18 [19].
• A chemical model demonstrated that the wavelength is appropriate to the 1',4'-iminopyrimidine tautomer of the 4'-aminopyrimidine ring in thiamin diphosphate [20].
• The degradation of bilirubin by this microsomal system has been compared to oxidation by a chemical model system involving H2O2 and Fe-EDTA (ethylenediaminetetraacetic acid) [21].

Gene context of Models, Chemical

• To test this hypothesis directly, using physical and chemical model systems, we synthesized, purified, and characterized A4 peptides corresponding to the human and rodent sequences [22].
• Chemical models of cytochrome P450 catalyzed insecticide metabolism. Application to the oxidative metabolism of carbamate insecticides [23].
• A quantum chemical model was built on the basis of the recent crystal structure of GAMT complexed with S-adenosylhomocysteine (SAH) and GAA [24].
• By contrast, the electron density profile calculated from a chemical model that includes lipids plus myelin basic protein (but not PLP) shows a higher density at the cytoplasmic than at the extracellular side.(ABSTRACT TRUNCATED AT 250 WORDS)[25]
• The mechanism for methane formation in methyl-coenzyme M reductase (MCR) has been investigated using the B3LYP hybrid density functional method and chemical models consisting of 107 atoms [26].

Analytical, diagnostic and therapeutic context of Models, Chemical

• However, covalent adducts corresponding to acylated protein also were not observed by electrospray ionization mass spectrometry, even with an assay that minimized the experimental dead time and which allowed for detection of N-acetyltyrosine acylated with EA in a chemical model system [27].
• The effect of route of administration on the outcome of the micronucleus test was evaluated in 2 laboratories by administering the model chemical, 1-beta-D-arabinofuranosylcytosine (Ara-C), by intraperitoneal injection (i.p.) and oral gavage (p.o.) to 2 mouse strains, MS/Ae and CD-1 [28].

References