Publications by authors named "P J Thomford"

Administration of lersivirine, a nonnucleotide reverse transcriptase inhibitor, daily by oral gavage to Sprague-Dawley rats for up to 2 yr was associated with decreased survival, decreased body weights, and an increase in neoplasms and related proliferative lesions in the liver, thyroid, kidney, and urinary bladder. Thyroid follicular adenoma and carcinoma, the associated thyroid follicular hypertrophy/hyperplasia, hepatocellular adenoma/adenocarcinoma, altered cell foci, and hepatocellular hypertrophy were consistent with lersivirine-related induction of hepatic microsomal enzymes. Renal tubular adenoma and renal tubular hyperplasia were attributed to the lersivirine-related exacerbation of chronic progressive nephropathy (CPN), while urinary bladder hyperplasia and transitional cell carcinoma in the renal pelvis and urinary bladder were attributed to urinary calculi.

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To investigate toxicity and neoplastic potential from chronic exposure to perfluorooctanesulfonate (PFOS), a two-year toxicity and cancer bioassay was conducted with potassium PFOS (K⁺ PFOS) in male and female Sprague Dawley rats via dietary exposure at nominal K⁺ PFOS concentrations of 0, 0.5, 2, 5, and 20 μg/g (ppm) diet for up to 104 weeks. Additional groups were fed 20 ppm for the first 52 weeks, after which they were fed control diet through study termination (20 ppm Recovery groups).

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The pharmacokinetics of perfluorooctanoate (PFOA) in cynomolgus monkeys were studied in a six-month oral capsule dosing study of ammonium perfluorooctanoate (APFO) and in a single-dose iv study. In the oral study, samples of serum, urine, and feces were collected every two weeks from monkeys given daily doses of either 0, 3, 10, or 20 mg APFO/kg. Steady-state was reached within four weeks in serum, urine, and feces.

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Perfluorooctanesulfonate (PFOS) is a widely disseminated persistent compound found at low (part-per-billion) concentrations in serum and liver samples from humans and fish-eating wildlife. This study investigated the hypotheses that early hepatocellular peroxisomal proliferation and hepatic cellular proliferation are factors in chronic liver response to dietary dosing, that lowering of serum total cholesterol is an early clinical measure of response to treatment, and that liver and serum PFOS concentrations are proportional to dose and cumulative dose after sub-chronic treatment. PFOS was administered in diet as the potassium salt at 0, 0.

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Ammonium perfluorooctanoate (APFO) is a processing aid in the production of fluoropolymers that has been shown to have a long half-life in human blood. To understand the potential toxicological response of primates, groups of male cynomolgus monkeys were given daily po (capsule) doses of either 0, 3, 10, or 30 (reduced to 20) mg/kg/day for 26 weeks. Two monkeys from each of the control and 10 mg/kg/day dose groups were observed for 90 days after the last dose.

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