George V. Pickwell

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Omeprazole, a proton pump inhibitor therapeutically administered for the treatment of gastric ulcers, induces the expression of cytochromes P4501A1/2 (CYP1A1/2) through transcriptional activation mediated by the Ah-dioxin)-receptor. Primary cultures of hepatocytes isolated from rabbit, rat, mouse and human livers were compared for CYP1A1/2 mRNA inducibility(More)
Green tea possesses significant anticancer activity in numerous experimental animal models, including demonstrated protection against aryl hydrocarbon induced cancers. The aryl hydrocarbon receptor (AhR) mediates the transcriptional activation of CYP1A1 and CYP1A2. In the present study, we investigated the effects of commercially available green tea(More)
Flavonoids, a family of naturally occurring polyphenolic compounds found in many fruits, nuts, vegetables, and beverages, appear to inhibit tumor promotion as part of their chemopreventive properties. To investigate at the molecular level the ability of flavonoids to inhibit tumor-promoting activity, we developed a cell line designed to screen for(More)
Induction of cytochrome (CYP) P4501A2 by such polycyclic aromatic hydrocarbons as 3-methylcholanthrene (3MC) can lead to the bioactivation of carcinogenic aromatic amines and heterocyclic amines. A 3MC response element was recently identified approximately 2.2 kb upstream of the transcription start site of the human CYP1A2 gene. Sequence analysis of this(More)
It was previously demonstrated that the commercial green tea extract Polyphenon 100 (P100), and to a lesser extent (-)-epigallocatechin-3-gallate (EGCG), partially antagonizes 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)-induced transcription of human CYP1A1 (Williams, S. N.; Shih, H.; Guenette, D. K.; Brackney, W.; Denison, M. S.; Pickwell, G. V.;(More)
Flavonoids are plant polyphenolic compounds ubiquitous in fruits, vegetables and herbs. The flavonol quercetin is one of the most abundant dietary flavonoids. It has diverse biological properties in cultured cells, including cytoprotection, and exhibits antitumorigenic effects in animal models. The mechanism(s) for the protective properties of flavonoids(More)
A physonectid siphonophore, Nanomia bijuga, associated with a verticallymigrating deep scattering layer, has been observed with a gasfilled float at depths in excess of 300 meters in the sea. This implies that gas is secreted and maintained in the pneumatophore against a diffusion gradient of 30 atmospheres or more. Analysis of the enclosed gases revealed(More)
Cytochrome P450 (CYP)1A2 is abundantly expressed in the liver of all vertebrate species. In most, its expression is restricted to the liver. Sequence analysis of the human CYP1A2 5'-flanking region from +3 to -3201 identified six E-box motifs within the 3-methylcholanthrene (MC) enhancer element (-1987 to -3201). The E-box motif is recognized by members of(More)