Duffy W Stephen

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Treatment of Candida albicans with low concentrations of either hydrogen peroxide or menadione (a superoxide generating agent) induces an adaptive response which protects cells from the lethal effects of a subsequent challenge with higher concentrations of these oxidants. Pre-treatment with either menadione or hydrogen peroxide is protective against cell(More)
Exponentially growing Saccharomyces cerevisiae cells are more sensitive to oxidants such as hydrogen peroxide and superoxides than stationary phase cells. Using disruption mutations in the genes encoding the two S. cerevisiae superoxide dismutases, we show that the principal mechanism of toxicity of redox-cycling compounds, such as menadione and plumbagin,(More)
The YAP1 and YAP2 genes encode yeast transcription factors of the c-jun family. We show that yeast mutants deleted for either the YAP1 or the YAP2 genes are hypersensitive to oxidants, particularly H2O2, and that these genes play a role in regulating the induction of the H2O2 adaptive stress response in Saccharomyces cerevisiae. They do not significantly(More)
The tripeptide gamma-L-glutamyl-L-cystinylglycine (glutathione) is one of the major antioxidant molecules of cells and is thought to play a vital role in buffering the cell against reactive oxygen species and toxic electrophiles. We wished to determine the role of glutathione in the protection of the yeast Saccharomyces cerevisiae against oxidative stress.(More)
Women with a genetic predisposition to breast cancer tend to develop the disease at a younger age with denser breasts making mammography screening less effective. The introduction of magnetic resonance imaging (MRI) for familial breast cancer screening programs in recent years was intended to improve outcomes in these women. We aimed to assess whether(More)
The tripeptide gamma-L-glutamyl-L-cysteinylglycine (glutathione) is one of the major antioxidant molecules of cells and plays a vital role in buffering the cell against reactive oxygen species and toxic electrophiles. In the yeast Saccharomyces cerevisiae, the first enzyme involved in glutathione biosynthesis, gamma-glutamylcysteine synthetase, is encoded(More)
In the era of mass screening for breast cancer with mammography, it has been noted that conventional tumor attributes and mammographic appearance are insufficient to account for the better prognosis of screen-detected tumors. Such prognostication may require additional updated pathological information regarding tumor phenotype (e.g., basal status) and(More)
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