0000000000464998
AUTHOR
Frans Setiabudi
showing 5 related works from this author
Radioactively labelled epoxides. part V. Tritium labelled K-region oxides and trans-dihydrodiols of pyrene, benzo[a]pyrene and dibenz[a, h]anthracene
1987
Tritium labelled K-region oxides of pyrene, benzo[a]pyrene and dibenz[a,h]anthracene have been prepared by cyclization of the corresponding trans-dihydrodiols which were obtained by reduction of K-region quinones with sodium borotritide in the presence of oxygen. This synthetic pathway not only yields two metabolically important radioactively labelled derivatives of polycyclic aromatic hydrocarbons in a simple and efficient manner, but also requires a rather inexpensive source of tritium.
cis- and trans-1,2-diphenylaziridines: induction of xenobiotic-metabolizing enzymes in rat liver and mutagenicity in Salmonella typhimurium.
1986
trans-Stilbene imine (trans-1,2-diphenylaziridine) is the nitrogen analog of trans-stilbene oxide, a potent inducer of several microsomal and cytosolic xenobiotic-metabolizing enzymes. Although the acute toxicity of cis- and trans-stilbene imines prevents their application at the usual dose for trans-stilbene oxide (400 mg/kg/day), it is apparent that the imines nevertheless potently induce several xenobiotic-metabolizing enzymes in rat liver. The IP administration of trans-stilbene imine resulted in statistically significant increases in the activities of aminopyrine N-demethylase, microsomal epoxide hydrolase, glutathione transferase (toward 1-chloro-2,4-dinitrobenzene, 1,2-dichloro-4-nit…
Expression of xenobiotic-metabolizing enzymes in propagatable cell cultures and induction of micronuclei by 13 compounds
1990
Activities of various xenobiotic-metabolizing enzymes were determined in 18 cell lines. Activities of cytochrome P450 reductase, microsomal epoxide hydrolase and glutathione transferase were detectable in all lines. The highest values were similar to the activities found in freshly isolated rat hepatocytes. Catalase activity was also present in all 12 investigated cell lines. Activity of UDP-glucuronosyl transferase was high in some lines, but low or undetectable in others. Activity of cytosolic epoxide hydrolase was not measurable in most lines, and was low in the others. Metabolism of benzo[a]pyrene was observed in eight out of nine examined lines, no activity being found in V79 cells. V7…
Radioactively labelled epoxides. Part VI. tritium-labelled mono- and dimethyl substituted phenyl oxiranes (styrene oxides)
1988
Tritium-labelled (E)- and (Z)-2,3-dimethyl-2-phenyl oxirane 4, (E)- and (Z)-2-methyl-3-phenyl oxirane 7 and 2,2-dimethyl-3-phenyl oxirane 11 have been prepared by reduction of the corresponding bromoketones with sodium borotritide to the corresponding bromohydrins followed by cyclization to the oxiranes. These oxiranes were successfully used as diagnostic substrates to distinguish between different forms of epoxide hydrolase and glutathione transferase.
Influence of the level of cytosolic epoxide hydrolase on the induction of sister chromatid exchanges by trans-beta-ethylstyrene 7,8-oxide in human ly…
1991
Abstract trans -β-Ethylstyrene 7,8-oxide, a substrate of cytosolic epoxide hydrolase, and 4-fluorochalcone oxide, an inhibitor of this enzyme, were investigated on induction of sister chromatid exchanges (SCE) in human lymphocytes. Both epoxides enhanced the frequency of SCE. 4-Fluorochalcone oxide at low concentration (2.5μM) inhibited cytosolic epoxide hydrolase activity towards trans -β-ethylstyrene 7,8-oxide in lymphocytes by 74% and had no effect on glutathione transferase activity using this substrate. At this concentration it did not induce SCE itself, but it potentiated the effect of trans -β-ethylstyrene 7,8-oxide several fold. In lymphocytes from different subjects, the number of …