Publications by authors named "Leroy C Folmar"

A variety of anthropogenic compounds are capable of binding to the estrogen receptor (ER) of vertebrate species. Binding of these chemicals to the ER can interfere with homeostasis by altering normal gene expression patterns. The purpose of this study was to characterize the expression of 30 genes using a sheepshead minnow (Cyprinodon variegatus) cDNA macroarray.

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Imposex, the development of male sex characteristics by female gonochoristic snails, has been documented globally and is causally associated with exposure to the ubiquitous environmental contaminant tributyltin (TBT). Elevated testosterone levels in snails also are associated with TBT, and direct exposure to testosterone has been shown to cause imposex. We discovered previously that the mud snail (Ilyanassa obsoleta)biotransforms and retains excess testosterone primarily as fatty acid esters.

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A variety of anthropogenic chemicals are capable of binding to the estrogen receptor of vertebrate species. Binding of these compounds can interfere with homeostasis by disrupting normal gene expression patterns. The purpose of this study was to investigate the feasibility of applying array technology as a monitoring tool for detecting the presence and distribution of estrogenic compounds in coastal habitats using sheepshead minnows as our model.

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Five natural, pharmaceutical, or xenobiotic chemicals [17beta-estradiol (E2), ethynylestradiol (EE2), diethystilbestrol (DES), methoxychlor (MXC), nonylphenol (NP)] were tested in two in vitro assays [yeast estrogen screen (YES), MCF-7 breast tumor cell proliferation (E-Screen)], and compared with previously reported results from two in vivo male sheepshead minnow vitellogenin (VTG) production studies. The purpose of this investigation was to determine how accurately the two in vitro assays predicted responses observed in live animals. EC50 values for all five chemicals were approximately one order of magnitude less sensitive in the YES assay than in the MCF-7 assay.

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