Publications by authors named "Kevin P Keenan"

Food is not only vital for the health and well-being of any living being, but it is a potential source of harmful chemicals, both natural and man-made. Further complicating this is the fact that most nutrients themselves are potentially toxic when consumed in excess. Deficiencies in some of these same nutrients may cause effects that resemble toxicosis or enhance the toxic potential of other nutrients or exogenous chemicals and drugs.

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The pregnancy-associated plasma protein-A knockout (PAPP-A KO) mouse is a model of reduced local insulin-like growth factor (IGF)-I activity with normal circulating IGF-I levels. In this study, PAPP-A KO mice had significantly increased mean (27%), median (27%), and maximum (35%) life span compared with wild-type (WT) littermates. End-of-life pathology indicated that the incidence of neoplastic disease was not significantly different in the two groups of mice; however, it occurred in older aged PAPP-A KO compared with WT mice.

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This study compared the effects of ad libitum (AL) overfeeding and moderate or marked dietary restriction (DR) on the pathogenesis of a metabolic syndrome of diabesity comprised of age-related degenerative diseases and obesity in a outbred stock of Sprague-Dawley (SD) rats [Crl:CD (SD) IGS BR]. SD rats were fed Purina Certified Rodent Diet AL (group 1), DR at 72-79% of AL (group 2), DR at 68-72% of AL (group 3) or DR at 47-48% of AL (group 4) for 106 weeks. Interim necropsies were performed at 13, 26, and 53 weeks, after a 7-day 5-bromo-2-deoxyuridine (BrdU)-filled minipump implantation.

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A HPLC-MS/MS Electrospray (ESI) method was developed and validated to quantify a peptide conjugate prodrug of doxorubicin (Dox-Con) and its active metabolites leucine-doxorubicin (Leu-Dox) and doxorubicin (Dox) in dog and rat plasma. The analytes were extracted from plasma by solid-phase extraction on a Bond Elut C8 cartridge and eluted with chloroform-methanol (2:1). Eluates were evaporated and reconstituted in acetonitrile-5 microM sodium trifluoroacetate in 0.

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This study compared the effects of ad libitum (AL) overfeeding and moderate or marked dietary restriction (DR) on the pathogenesis of aged-related pituitary gland changes in Sprague-Dawley (SD) rats. SD rats were fed Purina Certified Rodent Diet AL (group 1), DR at 72-79% of AL (group 2), DR at 68-72% of AL (group 3) or DR at 47-48% of AL (group 4) for 106 weeks. Interim necropsies were performed at 13, 26, and 53 weeks, after a 7-day 5-bromo-2-deoxyuridine (BrdU)-filled minipump implantation.

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