Showing papers in "Chemico-Biological Interactions in 1978"

TL;DR: The effects of the antifungal agent miconazole nitrate on the ergosterol biosynthesis in Candida albicans were investigated after in vitro contact with the drug and the accumulation of 14 α-methyl sterols suggests that this antifundal agent is a potent inhibitor of one of the metabolic steps involved in the demethylation at C-14.

TL;DR: It is concluded that 1,2-dichloroethane is activated by conjugation to glutathione, which gives a weak direct mutagenic effect, which is enhanced by addition of the postmitochondrial liver fraction (S-9).

TL;DR: In the rat this detoxification product of the potentially ultimate reactive AFB1-epoxide constitutes about 10% of the administered dose and thus underlines the quantitative importance of this activating pathway.

TL;DR: The results show a selective increase in cytochrome P-450 content by the cells in the centrilobular region after treatment with sodium phenobarbitone and a smaller increase by some of the Cells in the periportal region.

TL;DR: Vinyl chloride-derived chloroethylene oxide and/or chloroacetaldehyde behaves as a bifunctional alkylating agent towards deoxyadenosine and deoxycytidine residues of DNA.

TL;DR: The results support the hypothesis that H2Se or a similarly reduced selenide is the product of selenite metabolism by rat erythrocytes, and the properties of the Cd-Se complex suggested that it existed in a single form associated with different plasma components under various conditions.

TL;DR: A rapid, dose-dependent effect of TCDD, was the elevation of levels of organic-soluble fluorescent pigment in the heart, which was found to match a previously characterized fraction of lipofuscins in fluorescence spectrum and chromatographic properties.

TL;DR: The data presented show that the use of N BT to detect the presence of O2-.

TL;DR: Flow-dichroism measurements data strongly support the intercalation of the planar furocoumarin molecules between two base pairs of duplex DNA and equilibrium dialysis and spectrophotometric data show relatively low values of the association constants of the complexes and a small number of molecules able to intercalate in DNA, indicating that furoCoumarins have a relatively low affinity for DNA in the complex formation.

TL;DR: The formation of a transdihydrodiol is a necessary step in the metabolic pathway leading to DNA binding and that binding probably occurs through the generation of a reactive diol-epoxide.

TL;DR: Evidence is consistent with the transformation of DCE into chloroacetic acid by a mechanism involving the migration of one Cl atom and the loss of the other one, and electrolysis of one molecular proportion of the [14C]thiodiglycollic acid metabolite gives 1 equivalent of 14CO2.

TL;DR: Two forms of rabbit pulmonary cytochrome P-450 have been characterized spectrally and their activities in reconstituted monooxygenase systems investigated and indicated that metabolism at the 9 and 10 positions was insignificant in the case of cytochromes I but represented about 40% of the metabolites produced by cy tochrome II.

TL;DR: The reaction of trans- 7,8-dihydroxy-anti-9,10-epoxy-7,8,9, 10-tetrahydrobenzo(a)pyrene (anti-BPDE) with DNA prelabelled with [14C] and [3H]-purine precursors has indicated that in addition to the N2-position of guanine previously reported [10--12], this reaction also involves the N7

TL;DR: The structures and sterochemistry of the dihydrodiols were established by comparisons of their UV spectra and chromatographic characteristics using HPLC with those of authentic compounds or, when no authentic compounds were available, by UV, NMR and mass spectral analysis.

TL;DR: Results supported the hypothesis that H2Se or a similar product of GSSeSG reduction by glutathione reductase was the final product of selenite metabolism by rat erythrocytes.

TL;DR: It is established that the diamine oxidase-catalyzed metabolism of spermine and spermidine is necessary for their toxic effects in cell culture and that at higher concentrations of putrescine, cell proliferation was inhibited and this inhibition was unaffected by the addition of mM concentrations of AM.

TL;DR: The in vitro addition of trans-stilbene oxide (10(-6)--10(-2) M) did not affect hepatic epoxide hydrase or glutathione S-transferase activities, and none of the parameters were affected in pulmonary microsomes from treated rats.

TL;DR: The results suggest that the presence of a vinyl chloride or allyl chloride group in the molecule of these pesticides is responsible for the ability to induce point mutations in Salmonella and Streptomyces.

TL;DR: In vitro analysis of 3MC binding to DNA showed the nucleoside-bound adducts to be predominantly deoxyguanosine-dependent but that the early peaks were independent of base suggesting binding to another part of the DNA molecule, perhaps phosphate, i.e, phosphotriesters.

TL;DR: The significant increase in the permeability of some liposomal preparation noted even at the mercurial concentration of 10(-7) M strongly suggests that lipid in biomembrane could be one of the primary targets of these toxic substances.

TL;DR: The results suggest that the majority of reactive metabolites of DCB arise from secondary metabolism, i.e., the subsequent oxidation of the phenolic metabolites, and arene oxides, the primary products, appear to play a minor role in the protein binding ofDCB.

TL;DR: Computer models of three deoxyguanosine-carcinogen adducts in double-helical DNA are presented and the best fit within the double helix is evaluated, suggesting that this adduct could cause some local destabilization.

TL;DR: The absence of significant inhibition of DNA, RNA and protein syntheses in tumour cells found for [RhCODCl]2 at therapeutically active dosages, indicates that this substance has a different mechanism of action from that of cis-dichlorodiammine Pt(II) (cis-PDD).

TL;DR: EH activities of both liver and testes were very low in prepubertal rats, but they increased dramatically at the onset of puberty and reached maximum activities by 45 days of age, while benzo[a]pyrene hydroxylase activity and cytochrome P-450 content were at least 2-fold greater in microsomes from interstitial cells than in those from spermatogenic cells.

TL;DR: Statistically significant correlations have been demonstrated between carcinogenic activity, water-hexane partition coefficients and electronic factors for an extensive series of N-nitroso compounds, indicating that transport of the carcinogen to its active site has an important effect on its potency.

TL;DR: It is demonstrated that the use of microsomes to activate B[a]P is not a valid model system for delineating the in vivo mechanism of B[ a]P activation, and previous evidence for one-electron oxidation as the mechanism of activation of hydrocarbons in binding to nucleic acids is supported.

TL;DR: It is proposed that cis-Pt(II) damage stimulates the induction of a system which is involved in enhancing so called post replication repair in Chinese hamster V79 cells and that this induction might be inhibited by the presence of caffeine.

TL;DR: Sulfate conjugation of benzo[a]pyrene(BP) metabolites and derivatives was studied in this article, where the reaction sequence consisted of two steps; activation of sulfate ion to 3′phosphoadenosine-5′-phosphosulfate and transfer of the activated sulfate to the BP-derivatives.

TL;DR: The results suggest that there may be multiple forms of DMN-N-demethylase which are dependent on DMN concentration and respond differently to modifiers of the microsomal drug-metabolizing enzymes.