A highly purified and reconstituted hepatic microsomal monooxygenase system, completely free of epoxide hydrase and consisting of cytochrome P-448 from 3-methylcholanthrene-treated rats, NADPHcytochrome c reductase, phosphatidylcholine, and NADPH, metabolizes benzo [a Jpyrene to products highly mutagenic in strains TA 98 and TA 1538 of Salmonella typhimurium. The formation of mutagenic metaboli...

The present study was designed to determine the systemic influence of ultraviolet (UVB) irradiation upon subsequent carcinogenesis induced by benzo(a)pyrene. The source of UV irradiation consisted of six Westinghouse FS-40 fluorescent sunlamps. Female BALB/c mice received five 30-min dorsal UVB radiation treatments per week for 13 wk. At the end of 13 wk, irradiated and unirradiated mice receiv...

deuterium substitution on two ortho-substituted-och2-fragments in nitro-benzo-9-crown-3 induces low frequency shifts, positive mndcj, in all 13c nmr resonances which is an indication of the increased shielding in this crown ether. the magnitude of these shifts vary from 15dc7=716 to 54dc3=15 ppb for c7 and c3 cd3cocd3, and c6d6 on mndcj values were investigated. the mndcj values depended more o...

NRH:Quinone oxidoreductase 2 (NQO2) is an enzyme that catalyzes the reductive metabolism of quinones. C57BL/6 NQO2-/- mice lacking NQO2 gene expression were generated in our laboratory. The dorsal skin of NQO2-deficient mice was exposed to 7,12-dimethylbenz(a)anthracene (DMBA) or benzo(a)pyrene alone (complete carcinogen) or with 12-O-tetradecanoylphorbol-13-acetate (TPA) (initiation/promotion ...

The crystal structure of the title compound, [Rb(C(12)H(24)O(6))](3)[Sb(7)]·4NH(3), fills the gap between the already known Zintl anion ammoniates {[Cs(18-crown-6)](3)Sb(7)}(2)·9NH(3) [Wiesler (2007 ▶). Dissertation, Universität Regensburg, Germany] and [K(18-crown-6)](3)Sb(7)·4NH(3) [Hanauer (2007 ▶). Dissertation, Universität Regensburg, Germany]. As in the two known compounds, the anti-mony ...

The reaction of CdCl(2), 18-crown-6 and KI in water yields the title coordination polymer, [{K(C(12)H(24)O(6))}(2)Cd(2)I(6)](n). The potassium ion lies approximately in the plane of the crown ether, coordinated by all six crown ether O atoms and also by an iodide anion bound to a cadmium atom. A C atom of the crown ether is disordered over two positions with site occupancies of 0.77 (2) and 0.2...

The three quinone metabolites of carcinogenic benzo(a)pyrene, the isomeric benzo(a)pyrenediones (6, 12; 1,6; 3,6), are toxic to cultured hamster cells at low concentrations. The reduction in cell number, observed after treatment with these metabolites, is the result of both direct cell killing and the inhibition of growth, since DNA synthesis is inhibited very early after treatment with benzo(a...

OBJECTIVE The purpose of this study was to perform a radiographic follow-up evaluation after a 12-month healing period, following crown lengthening surgery. MATERIAL AND METHODS Twenty-three periodontally healthy subjects (mean age 32.5 years) that required crown lengthening surgery in premolars were recruited. In a total of 30 premolars, full thickness flaps, osseous resection, and flap sutu...