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Ryan P Braham

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A number of brominated flame retardants (BFRs) have been reported to interfere with the thyroid signaling pathway and cause oxidative stress in birds, yet the underlying shifts in gene expression associated with these effects remain poorly understood. In this study, we measured hepatic transcriptional responses of 31 genes in American kestrel hatchlings following in ovo exposure to one of three high-volume alternative BFRs: 1,2-bis(2,4,6-tribromophenoxy) ethane (BTPBE), bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), or 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (EHTBB). Hatchling kestrels exhibited shifts in the expression of genes related to oxidative stress (CYP, GSTA, SOD, GPx), thyroid hormone metabolism...
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The data was gathered to document the extent and severity of biomarkers of exposure to estrogenic chemicals in smallmouth and largemouth bass. Samples were collected from 2004 through 2010 at sites in five watersheds within the Chesapeake Bay watershed. A total of 281 largemouth bass were collected from the Potomac, Susquehanna, Patuxent and Rappahannock rivers and 1,384 smallmouth bass from the Potomac, Susquehanna and James. Fish were collected by boat electroshocking, euthanized in the field, weighed, measured, a blood samples collected and a necropsy completed that included documenting any visible abnormalities and collecting tissues for histopathology. Plasma obtained from blood samples was analyzed for vitellogenin,...
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The data were gathered as a preliminary assessment of estrogenicity under base-flow conditions at over 100 sites (lakes and streams) throughout New Jersey followed by more targeted sampling of smallmouth bass at nine sites with varying levels of estrogenicity. In 2016, 102 sites (lakes and streams) for the preliminary estrogenicity assessment were selected utilizing compiled results of previous monitoring studies (chemical and biological), current sampling networks, and other areas of concern based on input from stakeholders. Discrete grab surface water samples were collected under base-flow conditions in the fall of 2016 and analyzed for levels of estrogenicity using a bioluminescent yeast screen. Water samples...
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