Publications by authors named "Barry Stuart"

The polyisocyanates of 1,6-hexamethylene diisocyanate (HDI) find widespread commercial use as components of paints and in the formulation of light-stable polyurethane coating materials. This 2-year study assessed the oncogenicity of the diisocyanate monomer HDI in male and female Fischer-344 rats exposed 6 h/day, 5 days/week to mean analytical air concentrations of 0, 0.005, 0.

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In this subacute inhalation toxicity study of 1,6-hexamethylene diisocyanate (HDI), groups of 10 male and 10 female Sprague-Dawley rats were exposed to 0, 0.005, 0.0175, or 0.

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A key trait of developmental neurotoxicants is their ability to cause structural lesions in the immature nervous system. Thus, neuropathologic assessment is an essential element of developmental neurotoxicity (DNT) studies that are designed to evaluate chemically-induced risk to neural substrates in young humans. The guidelines for conventional DNT assays have been established by regulatory agencies to provide a flexible scaffold for conducting such studies; recent experience has launched new efforts to update these recommendations.

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Application of recently developed gene expression techniques using microarrays in toxicological studies (toxicogenomics) facilitate the interpretation of a toxic compound's mode of action and may also allow the prediction of selected toxic effects based on gene expression changes. In order to test this hypothesis, we investigated whether carcinogens at doses known to induce liver tumors in the 2-year rat bioassay deregulate characteristic sets of genes in a short term in vivo study and whether these deregulated genes represent defined biological pathways. Male Wistar rats were dosed with the four nongenotoxic hepatocarcinogens methapyrilene (MPy, 60 mg/kg/day), diethylstilbestrol (DES, 10 mg/kg/day), Wy-14643 (Wy, 60 mg/kg/day), and piperonylbutoxide (PBO, 1200 mg/kg/day).

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This is the first part of a series of three articles on trimming instructions of rat and mouse protocol organs and tissues in regulatory type toxicity studies. It is based on the experience made in the European RITA and American NACAD working groups and is an extended revision of trimming guides published in 1995 (Bahnemann et al.).

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When applied in toxicological studies, the recently developed gene expression profiling techniques using microarrays, which brought forth the new field of toxicogenomics, facilitate the interpretation of a toxic compound's mechanism of action. In this study, we investigated whether genotoxic carcinogens at doses known to induce liver tumors in the 2-year rat bioassay deregulate a common set of genes in a short-term in vivo study and, if so, whether these deregulated genes represent defined biological pathways. Rats were dosed with the four genotoxic hepatocarcinogens dimethylnitrosamine (4 mg/kg/day), 2-nitrofluorene (44 mg/kg/day), aflatoxin B1 (0.

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Historical control data have been shown to be valuable in the interpretation and evaluation of results from rodent carcinogenicity studies. Standardization of terminology and histopathology procedures is a prerequisite for meaningful comparison of control data across studies and analysis of potential carcinogenic effects. Standardization is particularly critical for the construction of a database that includes incidence data from different studies evaluated by pathologists in different laboratories.

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