BACKGROUND Melanins comprise a chemically-diverse group of polymeric pigments whose function is related to protection against physical and chemical stress factors. These polymers have current and potential applications in the chemical, medical, electronics and materials industries. The biotechnological production of melanins offers the possibility of obtaining these pigments in pure form and re...

PURPOSE The purpose of this research was to determine inter- and intrapatient differences in the pharmacokinetic profiles of etoposide and its genotoxic catechol metabolite during conventional multiple-day dosing of etoposide in pediatric patients. EXPERIMENTAL DESIGN Seven pediatric patients with various malignancies received etoposide at a dose of 100 mg/m(2) i.v. over 1 h daily for 5 days....

In Pseudomonas species and Moraxella calcoacetica, cis-cCs-muconate acts as the product inducer of catechol 1,2-oxygenase as well as -the substrate inducer for the co-ordinate induction of the enzymes catalysing its conversion into fl-oxoadipate enol lactone in Pseudomonas putida (Ornston, 1966) or into f-oxoadipoyl-CoA in Moraxella calcoacetica (Cainovas & Stanier, 1967; Canovas, Ornston & Sta...

Catechol estrogens are steroid metabolites that elicit physiological responses through binding to a variety of cellular targets. We show here that catechol estrogens directly inhibit soluble adenylyl cyclases and the abundant trans-membrane adenylyl cyclases. Catechol estrogen inhibition is non-competitive with respect to the substrate ATP, and we solved the crystal structure of a catechol estr...

Catechol estrogens are steroid metabolites that elicit physiological responses through binding to a variety of cellular targets. We show here that catechol estrogens directly inhibit soluble adenylyl cyclases and the abundant trans-membrane adenylyl cyclases. Catechol estrogen inhibition is non-competitive with respect to the substrate ATP, and we solved the crystal structure of a catechol estr...

the fruit of melia azedarach l. (meliaceae) was extracted with hexane, and its fatty acids methyl ester was analyzed using gc/ms. thirteen components representing 85.1% of the total extract were identified. the major components identified were methyl palmitate (18.8%), methyl linolenate (16.1%) and methyl linoleate (9.8%). the fruits’ extract had a lc50 of 5.5 ppm against the larvae of anophles...

Introduction The number of natural and synthetic 2H-pyran-2-one derivatives has been reported to exert notably the potential biological activity [1] and medicinal application such as: anticancer activity [2] hepatoprotective activity [3]. On the other hand, catechol derivatives are promising group of compounds worthwhile for further investigation, which may lead to the discovery of selective ac...

Tumor necrosis factor-alpha (TNF-α) is a proinflammatory cytokine that has been linked to breast cancer development. Estrogen metabolic pathway is also involved in breast carcinogenesis and DNA adducts formation. In this study we investigated the effect of TNF-α on the estrogen metabolic pathway in MCF-7, a breast cancer cell line. Capillary liquid chromatography/mass spectrometry (LC/MS) and H...