A methanol extract from Scrophulia ningpoensis showed suppressive effect of the SOS-inducing activity of the mutagen 2-(2-furyl)-3-(5-nitro-2-furyl)acrylamide (furylfuramide) in the Salmonella typhimurium TA1535/pSK1002 umu test. The methanol extract was re-extracted with hexane, dichloromethane, butanol, and water. An acidic fraction of the dichloromethane fraction showed a suppressive effect....

The edible part of fresh Chinese radish was chopped into small pieces, lyophilized, and then extracted sequentially with hexane, chloroform, and methanol. The solvent in each fraction was removed by evaporation under reduced pressure at 50-55 degrees C, and the residue was dissolved in dimethylsufoxide just before being tested for antimutagenicity as well as mutagenicity using the Salmonella/ma...

Three 5-nitrofuran derivatives showed carcinogenic activity when fed to female Holtzman rats at levels of 0.1 to 0.3% in a commercial diet for up to 44.5 weeks, while 2 other 5-nitrofuran derivatives and 5,5-diphenylhydantoin were inactive. Formic acid 2-[4-(5-nitro-2-furyl)-2-thiazolyl]hydrazide induced benign and malignant tumors of the mammary glands, adenomas or adenocarcinomas of the kidne...

Recent progress determining the structure of the host-encoded prion protein (PrP(C)) and the role of auxiliary molecules in prion replication permits a more rational approach in the development of therapeutic interventions. Our objective is to identify a new class of lead compounds that mimic the dominant negative PrP(C) mutants, which inhibit an abnormal isoform (PrP(Sc)) formation. A computat...

Binding of several nitroheterocycles by mammalian cells is a function of the ambient oxygen concentration; anoxic single cells bind up to 10 times as much of these drugs as do aerobic cells. We thus hypothesized that fluorescent nitroheterocyles could be used to quantitate the fraction of hypoxic cells in multicell systems, and this was tested in multicell spheroids using a relatively nontoxic ...

of the 27 nitrofuran derivatives tested had mutagenic effects on E. coli, but none of them had mutagenic effects on S. typhimurium. Twenty-five compounds had DNA-modifying effects on E. coli, and 24 compounds had effects on the DNA of S. typhimurium. Fifteen of the 27 compounds are known to be carcinogenic. Fourteen of these 15 carcinogenic derivatives had mutagenic effects on E. coli and DNA-m...