Congestive heart failure (HF) is characterized by inadequate nitric oxide (NO) production in the vasculature. Because NO is degraded by oxygen radicals, we hypothesized that NO is degraded faster in HF from inadequate peripheral arterial antioxidant reserves. HF was induced in male Sprague-Dawley rats by left coronary artery ligation. Vascular endothelial function was evaluated by measuring the...

The potential of the product unit neural networks built by using different memetic evolutionary algorithms for the simultaneous determination of mixtures of analytes based on dynamic responses was investigated. For this purpose, three methodologies for obtaining the structure and weights of neural networks were proposed, based on the combination of the evolutionary programming algorithm, a clus...

BACKGROUND Theaflavins including theaflavin (TF), theaflavin-3-gallate (TF3G), theaflavin-3'-gallate (TF3'G), and theaflavin-3,3'-digallate (TFDG), are the most important bioactive polyphenols in black tea. Because of their poor systemic bioavailability, it is still unclear how these compounds can exert their biological functions. The objective of this study is to identify the microbial metabol...

In skeletal muscle cells, GLUT1 is responsible for a large portion of basal uptake of glucose and dehydroascorbic acid, both of which play roles in antioxidant defense. We hypothesized that conditions that would decrease GLUT1-mediated transport would cause increased reactive oxygen species (ROS) levels in L6 myoblasts, while conditions that would increase GLUT1-mediated transport would result ...

A branched side chain pyrogallol[4]arene self-assembles into a previously-unreported cogged hydrogen-bonded nanotube structure in the solid state and self-assembles at the air-water interface on the Langmuir trough.

Crystals of the molybdo-/iron-sulfur protein pyrogallol:phloroglucinol hydroxyltransferase (transhydroxylase; EC 1.97.1.2) from Pelobacter acidigallici were grown by vapour diffusion in an N(2)/H(2) atmosphere using polyethylene glycol as a precipitant. In this microorganism, transhydroxylase converts pyrogallol to phloroglucinol in a unique reaction without oxygen transfer from water. Growth o...

A sensitive and selective procedure is presented for the voltammetric determination of cobalt. The procedure involves an adsorptive accumulation of cobalt Pyrogallol Red (PGR) complex on a stationary mercury drop electrode, followed by cathodic stripping voltammetry measurement of the reduction current of the adsorbed complex at –1.17 V (vs. Ag/AgCl). The optimum conditions for the determinatio...

As multiple mechanisms account for polyphenol-induced cytotoxicity, the development of structure-activity relationships (SARs) may facilitate research on cancer therapy. We studied SARs of representatives of 10 polyphenol structural types: (+)-catechin (1), (-)-epicatechin (2), (-)-epigallocatechin (3), (-)-epigallocatechin gallate (4), gallic acid (5), procyanidin B2 (6), procyanidin B3 (7), p...