Showing papers in "Biochemical Pharmacology in 1991"

TL;DR: In this paper, the ability of various plant flavonoids to inhibit 5-lipoxygenase and cyclooxygenases activities in rat peritoneal leukocytes, and to stimulate DNA degradation caused by the antibiotic bleomycin in the presence of ferric ions were investigated.

TL;DR: L'interaction entre l'oxyde nitrique (NO) and le groupement prosthetique de l'heme de la guanylate cyclase cytosolique est responsable du mecanisme de signal transduction qui provoque la biosynthese de GMP cyclique dans les cellules cibles suite a uen stimulus exterieur.

TL;DR: In this paper, it was shown that, apart from photolysis which makes no physiological contribution, release of nitric oxide from nitroplusside, in simple solutions and in biological tissue, occurs after nitroprusside has undergone reduction and lost cyanide.

TL;DR: Brain homeostatic mechanisms are disrupted by exposure to higher levels of lead, and the final pathway appears to be a breakdown in the blood-brain barrier.

TL;DR: In vitro, the 20-epi-vitamin D3 analogues were found to be considerably more potent as regulators of growth and differentiation in the human histiocytic lymphoma cell line U 937 than 1 alpha,25(OH)2D3, despite a practically unchanged calcemic activity in vivo.

TL;DR: It is concluded that BLM molecules possess very intense cytotoxic activity which in non-EP cells is drastically limited by the intact plasma membrane, and in these intact cells, the plasma membrane is responsible for the unusual upward concave curvature of the SRC resulting from exposure to BLM.

TL;DR: In this article, the use of methylene blue as a means of suppressing the production of Superoxide radicals O 2 − by acting as an alternative electron acceptor for xanthine oxidase.

TL;DR: Analysis of RNA indicated 20- to 50-fold higher levels of NQO1 gene expression in the liver tumors and in the tissue surrounding the tumors of patients with hepatocarcinoma than in normal individuals.

TL;DR: In vitro observations establish that a P450 enzyme of the IIIA sub-family is involved in the oxidative demethylation of tamoxifen in human liver.

TL;DR: The ability of a variety of anti-inflammatory drugs to inhibit conversion of H2O2 to HOCl was assessed and an optimum reduction potential was reached, enabling inhibitors to reduce MPO to compound II, but prevents them from reducing compound II back to the active enzyme.

TL;DR: It is concluded that desferrioxamine cannot enter cells other than by pinocytosis and that, once internalized, it will remain in the lysosomes.

TL;DR: In this article, five phenolic compounds and pyridoxine were studied for their activities as both scavengers of Superoxide anions and inhibitors of lipid peroxidation.

TL;DR: The allele distribution of the Caucasian population described here differs from that reported after Southern blot analysis of a Japanese population, and the most frequent allele at the polymorphic nat locus in Caucasians, S1, is absent in the Japanese population.

TL;DR: It is suggested that Hg(II) at low concentrations depletes mitochondrial GSH and enhances H2O2 formation in kidney mitochondria under conditions of impaired respiratory chain electron transport.

TL;DR: Seven aldehyde dehydrogenases found in the cytosol of mouse stomach epithelium and cornea catalyzed the oxidation of retinaldehyde to retinoic acid, a metabolite of vitamin A that promotes the differentiation of epithelial and other cells.

TL;DR: Results presented here demonstrate that either human BChE or FBS-AChE is an effective prophylactic measure sufficient to protect mice from multiple LD50S of soman without the administration of post-treatment supportive drugs.

TL;DR: These recent developments have provided new therapeutic perspectives for the management of Parkinson's disease and seizure disorders via the use of selective inhibitors and amino acid amine prodrug substrates of MAO-B.

TL;DR: Lanthionine-containing peptide antibiotics inhibit phospholipase A2 indirectly by specifically sequestering the substrate phosphatidylethanolamine, analogous to the one described for the protein lipocortin.

TL;DR: The results indicate that the capacity of cytochrome P450IIE1 to reduce oxygen is related to its ability to generate alcohol free radicals and suggest that ferric cyto chrome P450-oxygen complex might act as oxidizing species toward alcohols.

TL;DR: It is shown in vitro that herbimycin A directly inactivates p60 v-src kinase by conjugating with SH group(s) of the kinase, raising the possibility that the molecular target of the antibiotic for reversion of v- src transformation is the p- src itself.

TL;DR: It is proposed that CO can be considered and experimentally used as a convenient activator of soluble G-cyclase in smooth muscle and platelets and about doubles cGMP levels in guinea pig ileal strips.

TL;DR: Whether human T-lymphocytes contain one or both of these pharmacologically distinguishable high-affinity cAMP-PDE isozyme families is determined, and the effects of selective inhibitors of these PDEs on lymphocyte blastogenesis are determined.

TL;DR: The metabolic profile of seven subfamilies of cytochrome P450 (P450IA, IIA, IIB, IIC, IIE, IIIA, IVA) was studied in rat liver (in vivo) and in primary hepatocyte cultures (in vitro) after treatment with various inducers as discussed by the authors.

TL;DR: Ninhydrin was found also to be hydrophilic although this compound, in contrast to alloxan and its derivatives, was quite stable in aqueous solution, which may explain why ninhydrin does not share with allxan a selective toxic effect upon the pancreatic B-cell.

TL;DR: DT diaphorase, purified to homogeneity from human Hep G2 cells, did metabolize CB 1954 to this 4-hydroxylamino product, but the rate of CB 1954 reduction and thus production of the cytotoxic product, was much lower than that of purified Walker enzyme.

TL;DR: In vivo, administration of pure EPA to weight losing mice bearing the MAC16 adenocarcinoma completely prevented weight loss and tumour growth rate, suggesting that a correlation may exist between the inhibition of cachexia and the inhibitory effect of EPA.

TL;DR: Results demonstrate that menadione possesses a broad spectrum of anticancer activity and suggest the potential utility of this agent in cancer therapy and the interactions of fifteen clinically utilized anticancer drugs with MD were examined in vitro.