Search Results - "Holcombe, Gary W."

Early temporal effects of three thyroid hormone synthesis inhibitors in Xenopus laevis by Tietge, Joseph E., Butterworth, Brian C., Haselman, Jonathan T., Holcombe, Gary W., Hornung, Michael W., Korte, Joseph J., Kosian, Patricia A., Wolfe, Marilyn, Degitz, Sigmund J.

“…Thyroid axis disruption is an important consideration when evaluating risks associated with chemicals. Bioassay methods that include thyroid-related endpoints…”
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Progress towards Development of an Amphibian-Based Thyroid Screening Assay Using Xenopus laevis. Organismal and Thyroidal Responses to the Model Compounds 6-Propylthiouracil, Methimazole, and Thyroxine by Degitz, Sigmund J., Holcombe, Gary W., Flynn, Kevin M., Kosian, Patricia A., Korte, Joseph J., Tietge, Joseph E.

“…In response to the initial Endocrine Disruptor Screening and Testing Advisory Committee (EDSTAC) recommendations, research was conducted on the development of…”
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Sex reversal of the amphibian, Xenopus tropicalis, following larval exposure to an aromatase inhibitor by Olmstead, Allen W., Kosian, Patricia A., Korte, Joseph J., Holcombe, Gary W., Woodis, Kacie K., Degitz, Sigmund J.

“…Aromatase is a steroidogenic enzyme that catalyzes the conversion of androgens to estrogens in vertebrates. Modulation of this enzyme's activity by xenobiotic…”
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Metamorphic inhibition of Xenopus laevis by sodium perchlorate: Effects on development and thyroid histology by Tietge, Joseph E., Holcombe, Gary W., Flynn, Kevin M., Kosian, Patricia A., Korte, Joseph J., Anderson, Leroy E., Wolf, Douglas C., Degitz, Sigmund J.

“…The perchlorate anion inhibits thyroid hormone (TH) synthesis via inhibition of the sodium‐iodide symporter. It is, therefore, a good model chemical to aid in…”
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Evaluation of gene expression endpoints in the context of a Xenopus laevis metamorphosis-based bioassay to detect thyroid hormone disruptors by Zhang, Fang, Degitz, Sigmund J., Holcombe, Gary W., Kosian, Patricia A., Tietge, Joseph, Veldhoen, Nik, Helbing, Caren C.

“…Thyroid hormones (TH) are important in growth, development and the maintenance of proper cellular metabolism in vertebrates. Amphibian metamorphosis is…”
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Comparative toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to seven freshwater fish species during early life-stage development by Elonen, Gregory E., Spehar, Robert L., Holcombe, Gary W., Johnson, Rodney D., Fernandez, Joseph D., Erickson, Russell J., Tietge, Joseph E., Cook, Philip M.

“…The toxic effects of 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD) to fathead minnow (Pimephales promelas), channel catfish (Ictalurus punctatus), lake herring…”
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Trenbolone causes mortality and altered sexual differentiation in Xenopus tropicalis during larval development by Olmstead, Allen W., Kosian, Patricia A., Johnson, Rodney, Blackshear, Pamela E., Haselman, Jonathan, Blanksma, Chad, Korte, Joseph J., Holcombe, Gary W., Burgess, Emily, Lindberg-Livingston, Annelie, Bennett, Blake A., Woodis, Kacie K., Degitz, Sigmund J.

“…Trenbolone is an androgen agonist used in cattle production and has been measured in aquatic systems associated with concentrated animal‐feeding operations. In…”
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Effects of 4- tert-octylphenol on Xenopus tropicalis in a long term exposure by Porter, Karen L., Olmstead, Allen W., Kumsher, David M., Dennis, William E., Sprando, Robert L., Holcombe, Gary W., Korte, Joseph J., Lindberg-Livingston, Annelie, Degitz, Sigmund J.

“…Endocrine disrupting chemicals that activate the estrogen receptor are routinely detected in the environment and are a concern for the health of both exposed…”
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Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay: Part 1. Effects on the brain by Helbing, C.C, Bailey, C.M, Ji, L, Gunderson, M.P, Zhang, F, Veldhoen, N, Skirrow, R.C, Mu, R, Lesperance, M, Holcombe, G.W

“…Thyroid hormones (TH), thyroxine (T₄) and 3,5,3'-triiodothyronine (T₃), play crucial roles in regulation of growth, development and metabolism in vertebrates…”
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Assessment of the Risk of Solar Ultraviolet Radiation to Amphibians. I. Dose-Dependent Induction of Hindlimb Malformations in the Northern Leopard Frog (Rana pipiens) by Ankley, Gerald T, Diamond, Stephen A, Tietge, Joseph E, Holcombe, Gary W, Jensen, Kathleen M, DeFoe, David L, Peterson, Ryan

“…A number of environmental stressors have been hypothesized as responsible for recent increases in limb malformations in several species of North American…”
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Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay: Part 2. Effects on the tail and hindlimb by Helbing, C.C, Ji, L, Bailey, C.M, Veldhoen, N, Zhang, F, Holcombe, G.W, Kosian, P.A, Tietge, J, Korte, J.J, Degitz, S.J

“…Thyroid hormones (TH), thyroxine (T₄) and 3,5,3'-triiodothyronine (T₃), play crucial roles in regulation of growth, development and metabolism in vertebrates…”
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Effects of ultraviolet light and methoprene on survival and development of Rana pipiens by Ankley, Gerald T., Tietge, Joseph E., DeFoe, David L., Jensen, Kathleen M., Holcombe, Gary W., Durhan, Elizabeth J., Diamond, Stephen A.

“…Recently a suite of relatively specific hindlimb deformities have been observed in several anuran species in North America. These deformities include ectopic…”
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In vivo assessment and potential diagnosis of xenobiotics that perturb the thyroid pathway: Proteomic analysis of Xenopus laevis brain tissue following exposure to model T4 inhibitors by Serrano, Jose, Higgins, LeeAnn, Witthuhn, Bruce A., Anderson, Lorraine B., Markowski, Todd, Holcombe, Gary W., Kosian, Patricia A., Korte, Joseph J., Tietge, Joseph E., Degitz, Sigmund J.

“…As part of a multi-endpoint systems approach to develop comprehensive methods for assessing endocrine stressors in vertebrates, differential protein profiling…”
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Developmental toxicity of methoprene and several degradation products in Xenopus laevis by Degitz, Sigmund J., Durhan, Elizabeth J., Tietge, Joseph E., Kosian, Patricia A., Holcombe, Gary W., Ankley, Gerald T.

“…Methoprene is an insect juvenile growth hormone mimic, which inhibits pupation and is used for the control of emergent insect pests such as mosquitoes…”
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Comparing the Effects of Stage and Duration of Retinoic Acid Exposure on Amphibian Limb Development: Chronic Exposure Results in Mortality, Not Limb Malformations by Degitz, Sigmund J., Holcombe, Gary W., Kosian, Patricia A., Tietge, Joseph E., Durhan, Elizabeth J., Ankley, Gerald T.

“…Recently, high frequencies of malformations have been reported in amphibians across the United States. It has been suggested that the malformations may be the…”
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Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay by Helbing, Caren C., Ji, Lan, Bailey, Carmen M., Veldhoen, Nik, Zhang, Fang, Holcombe, Gary W., Kosian, Patricia A., Tietge, Joseph, Korte, Joseph J., Degitz, Sigmund J.

“…Thyroid hormones (TH), thyroxine (T 4) and 3,5,3′-triiodothyronine (T 3), play crucial roles in regulation of growth, development and metabolism in vertebrates…”
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Identification of gene expression indicators for thyroid axis disruption in a Xenopus laevis metamorphosis screening assay by Helbing, Caren C., Bailey, Carmen M., Ji, Lan, Gunderson, Mark P., Zhang, Fang, Veldhoen, Nik, Skirrow, Rachel C., Mu, Ruixia, Lesperance, Mary, Holcombe, Gary W., Kosian, Patricia A., Tietge, Joseph, Korte, Joseph J., Degitz, Sigmund J.

“…Thyroid hormones (TH), thyroxine (T 4) and 3,5,3′-triiodothyronine (T 3), play crucial roles in regulation of growth, development and metabolism in vertebrates…”
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Effects of water quality on development of Xenopus laevis: A frog embryo teratogenesis assay-Xenopus assessment of surface water associated with malformations in native anurans by Tietge, Joseph E., Ankley, Gerald T., DeFoe, David L., Holcombe, Gary W., Jensen, Kathleen M.

“…The purpose of this work was to determine if surface water from a site in Minnesota, USA, with malformed anurans was able to elicit adverse developmental…”
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Reproductive toxicity and disposition of 2,3,7,8-tetrachlorodibenzo-p-dioxin in adult brook trout (Salvelinus fontinalis) following a dietary exposure by Tietge, J.E. (U.S. Environmental Protection Agency, Duluth, MN.), Johnson, R.D, Jensen, K.M, Cook, P.M, Elonen, G.E, Fernandez, J.D, Holcombe, G.W, Lothenbach, D.B, Nichols, J.W

“…Adult brook trout (Salvelinus fontinalis) were exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) with a contaminated trout pellet diet to determine the…”
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Toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin to early life stage brook trout (Salvelinus fontinalis) following parental dietary exposure by Johnson, R.D. (U.S. Environmental Protection Agency, Duluth, MN.), Tietge, J.E, Jensen, K.M, Fernandez, J.D, Linnum, A.L, Lothenbach, D.B, Holcombe, G.W, Cook, P.M, Christ, S.A, Lattier, D.L

“…The toxicity of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to the early life stages of F1 generation brook trout (Salvelinus fontinalis) was determined, when…”
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