Showing papers in "Chemico-Biological Interactions in 1996"

TL;DR: Alcohol in lower doses may act as an antioxidant on low density lipoproteins and thereby have an anti-atherosclerotic property and regular exercise and carbohydrate-rich diets seem to increase the resistance against oxidative stress.

TL;DR: Hibiscus protocatechuic acid demonstrated protective effects against cytotoxicity and genotoxicity of hepatocytes induced by tert-butylhydroperoxide, and exhibited an effective ability to quench 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH).

TL;DR: The present findings clearly indicate that cruciferous vegetables contain DNA damaging constituents and raise the question whether greatly increased consumption of Brassica vegetables or their concentrated constituents as a means for cancer prevention is indeed recommendable.

TL;DR: Reversible inhibition of GST was the major mechanism of inhibition of DNPSG-excretion in melanoma cells, except in the cases of curcumin and ethacrynic acid, which compounds also inactivated GSTP1-1 by covalent modification.

TL;DR: Using hepatoma cell suspensions and rat liver subcellular fractions, it was found that ortho-quinones underwent preferential enzymatic one-electron redox-cycling and produced superoxide anion radical (O2-.) and/or Ortho-semiquinone anion or alternant radicals.

TL;DR: Neither p-anisic acid, an inhibitor of cytosolic methyltransferases, nor 2,3-dichloro-alpha-methylbenzylamine, an inhibited the conversion of inorganic arsenic to mono- or dimethylated metabolites, suggesting that an endogenous divalent cation might be involved in enzymatic methylation of arsenic.

TL;DR: By computer analysis of available promoter sequences, dioxin-responsive elements in the promoter regions of many putative AhR regulated and therefore dioxIn-inducible genes are identified.

TL;DR: Inhibition of Na+/K+-ATPase and Mg2+- ATPase activities by in vitro exposure to Cd2+, Pb2+ and Mn2+ was investigated in rat brain synaptic plasma membranes and Dixon plots of SPM data indicated that equilibrium binding of metals occurs at sites causing enzyme inhibition.

TL;DR: It is shown that Cr(III) + H2O2-->Cr(IV) + .OH + OH generates oxidative damage to DNA through a Fenton-like reaction, which is less efficient than ascorbate and no Cr(V) signals were detected.

TL;DR: The results suggest that nicotinamide had significant ability to protect against photosensitization-induced cytotoxicity and cell damage and that it may do so by its ability to react with 102 and other reactive oxygen species.

TL;DR: The ability of the HAAs to adsorb to the plant cell walls increased with increasing hydrophobicity of the HAA, measured as the calculated logarithm of the partition coefficient between 1-octanol and water (C logP).

TL;DR: Evidence is shown that, without stimulation, vitellogenin mRNA precursor is expressed in both male and female immature fish, and it is suggested that estrogen and nonylphenol may be involved in a post-transcriptional regulation process -- possibly in the initiation of pre-mRNA splicing.

TL;DR: Curcumin, in a dose-dependent manner, inhibited the formation of covalent adduct between aflatoxin B1 and DNA, as catalyzed by microsomes or a reconstituted microsomal monooxygenase system, and may inhibit chemical carcinogenesis by modulating cytochrome P450 function.

TL;DR: Data indicate that the cytotoxic activity of 13-methoxy-15-oxozoapatlin is mediated in part by covalent reaction with a cellular component (such as sulfhydryl-containing protein) by means of a Michael-type addition, and this results in the blockage of cell-cycle progression.

TL;DR: The results show that the volume of the peroxisomal compartment and the ubiquinone content in animal tissues are interrelated.

TL;DR: Examination of teratogenicity, in pregnant mice, of a number of synthetic retinoids with varying degrees of receptor selectivity found that although all RAR agonists were strong teratogens, their potencies varied over a wide magnitude.

TL;DR: Inhibition of microtubule assembly by arenastatin A and the triamide 6 and five synthetic analogs and also depolymerized preformed microtubules was examined.

TL;DR: Results indicate that actin polymerization and assembly must be an essential component of the primary, active event of the engulfment phase of phagocytosis.

TL;DR: PYRV can be used as a specific marker of in vivo doses of DEB whereas THBV may be applied for the dosimetry of the metabolite (1,2-dihydroxyethyl)oxirane), which requires-due to its tertiary amine structure-other techniques.

TL;DR: Analysis of variance of the DNA adduct levels among the 14 pairs of individuals working at the same news-stands revealed little effect of the environmental air exposure on the DNAAdduct level.

TL;DR: The fungus, Cunninghamella elegans, was used as a microbial model of mammalian drug metabolism to biotransform a tricyclic antidepressant, cyclobenzaprine, and it was demonstrated that the fungalBiotransformation system could be used to predict and synthesize the mammalian drug metabolites.

TL;DR: It is found that when arenediazonium ions of the general structure p- X-ArN2+ are allowed to react with ctDNA or incubated with cells under conditions that produce p-X-Ar, DNA adducts are formed with guanine.

TL;DR: It was observed that OH radicals generated by 0.1 mM Fe2+/2.5 mM H202 at 25 degrees C for 1 h led to the production of 5-hydroxymethylcytosine (5MHC) and when OH generation was performed with UV light, the following products were observed: 5-Hydroxy-5-methylhydantoin,5-hydroxyhydantoIn, 5MHC, thymine glycol (two isomers) and

TL;DR: The covalent binding of the benzene metabolites BQ and BPQ to critical thiol groups of tubulin inhibits MT formation under cell-free conditions and may also interfere with the formation of a functional spindle apparatus in the mitotic cell, thus leading to the abnormal chromosome segregation and aneuploidy induction reported for benzene.

TL;DR: The hypothesis that the toxicity of 4-methylphenol is dependent on the formation of a reactive quinone methide intermediate is supported.

TL;DR: The results showed that the four solvents have different effects on specific cytochrome P450 isozymes and on the metabolism of both endogenous and exogenous substances.

TL;DR: F fumes generated from two road grade bitumens, in such a way that they were representative of the fumes produced in the field, indicate that the PAHs analysed are not the sole components responsible for adduct formation from BFCs, but that an important contribution comes from other PACs.

TL;DR: Alkaline elution of cells/nuclei prepared from exposed animals constitutes a sensitive, rapid and versatile technique to study organ- and cell-specific genotoxicity in vivo and indicates that the distribution characteristics of DBCP are of major importance for DNA damage and its persistence in various organs of rats.

TL;DR: 32P-postlabeling can be used successfully to detect the major adduct, 7-hydroxyethylthio- ethyldeoxyguanosine 5'-phosphate (HETEpdG), that is formed in DNA by sulfur mustard and growth of fibroblast cells, assayed by trypan-blue exclusion, is somewhat inhibited by 2 microM SM, indicating that 32P- postlabeling has the requisite sensitivity to detect adducts at levels of SM

TL;DR: The data suggest that bioreductive activation of antitumor quinones by DTD results in induction of apoptosis in human colon carcinoma cells.