Hepatitis C virus (HCV) is a serious global problem, and present therapeutics are inadequate to cure HCV infection. In the present study, various antiviral assays show that As2O3 at submicromolar concentrations is capable of inhibiting HCV replication. The 50% effective concentration (EC50) of As2O3 required to inhibit HCV replication was 0.35 microM when it was determined by a reporter-based H...

BACKGROUND Eleven phosphodiesterase (PDE) gene families (PDE1-11) have been identified, and some PDE isoforms are selectively expressed in various cell types. Previously, we reported PDE1, PDE3 and PDE4 expressions in human malignant melanoma cells. However, the expression and role of PDE5 in malignant melanoma cells is not clear. Therefore, we characterized PDE5 in human malignant melanoma MAA...

Employing the technique of cell fractionation, Schneider and Hogeboom (’56) described the localization of certain oxidative enzymes. They reported that cytochrome oxidase and succinic dehydrogenase were found only in the mitochondrial fraction while isocitric dehydrogenase was present in the supernatant and DPN and TPN cytochrome c reductases were observed to be in both fractions. More recently...

A dye reduction method for determining a definitive endpoint with agar dilution susceptibility testing has been developed. Bacterial growth was determined by applying to the inoculum spot a dye solution containing 2-(p-iodophenyl)-3-(pnitrophenyl)-5-phenyltetrazolium chloride and phenazine methosulfate. Viable colonies reduced the tetrazolium salt to a visible red color within 3 to 5 min. The m...

A colorimetric assay based on the reduction of a tetrazolium salt [2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide (XTT)] for rapidly determining the susceptibility of Pseudomonas aeruginosa isolates to bactericidal antibiotics is described. There was excellent agreement between the tobramycin and ofloxacin MICs determined after 5 h using the XTT assay and after 18 h u...

Standard models of ion channel voltage gating require substantial movement of one transmembrane segment, S4, of the voltage sensing domain. Evidence comes from the accessibility to external methanethiosulfonate (MTS) reagents of the positively charged arginine residues (R) on this segment. These are first mutated to cysteines (C), which in turn react with MTS reagents; it is assumed that the C ...

Exposure to vapours of volatile chemicals is a major occupational and environmental health concern. Toxicity testing of volatile organic compounds (VOCs) has always faced significant technological problems due to their high volatility and/or low solubility. The aim of this study was to develop a practical and reproducible in vitro exposure technique for toxicity testing of VOCs. Standard test a...

BACKGROUND We evaluated the effects of fibronectin, collagen, cadherin, and laminin based extracellular matrix (ECM) protein mimetics coated with mussel derived adhesive protein (MAP) on adhesion and proliferation of chorionic mesenchymal stem cells (cMSCs). METHODS Human placental chorionic tissues from term third-trimester pregnancies (n=3) were used. The cMSCs were cultured on rationally d...

Methods are presented for the intramitochondrial localization of various diphosphopyridine nucleotide and triphosphopyridine nucleotide-linked dehydrogenases in tissue sections. The cytochemical reactions studied involve the oxidation of the substrates by a specific pyridino-protein. The electron transfer of tetrazolium salt is mediated by the diaphorase system associated with the dehydrogenase...