Katherine S Morrison

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UNLABELLED The reproducibility of (+/-)-alpha-[11C] dihydrotetrabenazine (DTBZ) measures in PET was studied in 10 healthy human subjects, aged 22-76 y. METHODS The scan-to-scan variation of several measures used in PET data analysis was determined, including the radioactivity ratio (target-to-reference), plasma-input Logan total distribution volume (DV),(More)
UNLABELLED The reproducibility of [11C]SCH 23390 in PET was studied in 10 normal human subjects. METHODS The scan-to-scan variation of several measures used in PET data analysis, including the radioactivity ratio, plasma-input Logan total distribution volume (DV), plasma-input Logan DV ratio (DVR) and tissue-input Logan Bmax/Kd values, was determined. (More)
UNLABELLED Graphical methods to analyze tracer time-course data allow reliable quantitation of the rate of incorporation of tracer from plasma into a "trapped" kinetic component, even when the details of the kinetic model are unknown. Applications of the method over long time periods often expose the slow reversibility of the trapping process. In the(More)
In proliferating C2C12 myoblasts, serum and physiological concentrations of insulin and IGF-I stimulated protein synthesis and RNA accretion. After fusion, the multinucleated myotubes remained responsive to serum but not to insulin or IGF-I, even though both insulin and type-I IGF receptor mRNAs increased in abundance. Protein synthetic responses to insulin(More)
The rates of [3H]N(tau)-methylhistidine (3-MH) accumulation in the medium, following pulse labelling of cells for 48 h with [3H]methionine, were used to measure myofibrillar protein degradation. In fused C2C12 myotubes, incubation for 24 or 48 h after the labelling period gave rates of myofibrillar degradation of 38 and 42%/day. In a leucine free medium,(More)
Cynomolgus and rhesus monkeys have been studied via PET with [18F]-L-6 fluorodopa tracer. Striatal fluorodopa uptake rate constants have been derived by graphical analysis of transaxial slice images centered on the striata. The differences between pairs of values of the rate constant, obtained from two scans on the same monkey separated by two weeks or(More)
Insulin stimulated a concentration-dependent increase in protein synthesis in L6 myoblasts which was significant at 1 nM. This response was not prevented by the transcription inhibitor, actinomycin D. The protein kinase C (PKC) inhibitor, Ro-31-8220, and downregulation of PKC by prolonged incubation of cells with 12-O-tetradecanoylphorbol-13-acetate (TPA),(More)
The uptake rate constant and the loss rate constant that expresses the reversibility of the uptake process of 6-[18F]fluoro-L-Dopa (FDOPA) were measured by positron emission tomography in the striatum of normal rhesus monkeys and in monkeys with unilateral lesions of the dopaminergic nigro-striatal pathway, induced by intracarotid injection of(More)
In C2C12 myoblasts, 12-O-tetradecanoylphorbol-13-acetate (TPA) stimulated a phospholipase D (PLD) to degrade phosphatidylcholine (PC) as measured by the release of choline and an increase in the formation of phosphatidic acid (PA) (or phosphatidylbutanol [PtdBuOH] in the presence of 0.5% butanol). Exogenous PLD also stimulated choline release, PA and(More)