Ellen M Roberts

Learn More
A three-dimensional, six-segment model was applied to the pitching motion of three professional pitchers to analyze the kinematics and kinetics of the hips, upper trunk, humerus and forearm plus hand of both the upper limbs. Subjects were filmed at 250 frames per second. An inverse dynamics approach and angular momentum principle with respect to the(More)
The effect of dexmedetomidine DEX on cytochrome P4502D6 (CYP2D6)-dependent dextromethorphan O-demethylase (DEXTROase) activity was studied using native human liver microsomes. DEX (0.01-4.0 microM inhibited DEXTROase activity (IC50 = 1.8 +/- 0.25 microM; mean +/- SD; N = 5 livers) and was less potent than quinidine (QND), prototypical and clinically(More)
Cotton fibers (Gossypium hirsutum L.) developing in vitro responded to cyclic temperature change similarly to those of field-grown plants under diumal temperature fluctuations. Absolute temperatures and rates of temperature change were similar under both conditions. In vitro fibers exhibited a "growth ring" for each time the temperature cycled to 22 or 15(More)
ABT-378 is a potent in vitro inhibitor of the HIV protease and is currently being developed for coadministration with another HIV protease inhibitor, ritonavir, as an oral therapeutic treatment for HIV infection. In the present study, the effect of ritonavir, a potent inhibitor of cytochrome P-450 (CYP) 3A, on the in vitro metabolism of ABT-378 was(More)
Component and resultant external forces and torques at ankle, knee, and hip joints of unrestrained lower extremity motion were computed as resultant limb velocities were systematically changed. Cinematographic and modeling techniques were used to analyze 45 trials of five skilled soccer players who performed slow, medium and fast velocity kicks. A model of(More)
Central tolerance depends upon Ag-mediated cell death in developing thymocytes. However, the mechanism of induced death is poorly understood. Among the known death-inducing proteins, TNF was previously found to be constitutively expressed in the thymus. The role of TNF in thymocyte negative selection was therefore investigated using TNF receptor(More)
The activity of human liver microsomal cytochrome P450 1A2 (CYP1A2) is readily estimated by following the O-deethylation of [O-ethyl C]phenacetin (PODase). The basis of the assay is the quantitative measurement of [C]acetaldehyde, remaining in the supernatant of assay incubates, after extraction of unmetabolized [O-ethyl C]phenacetin with charcoal. In the(More)
Cytochrome P450 (CYP) activity in human liver microsomes was measured after the O-demethylation of [O-methyl 14C]naproxen (NAPase). The formation of [14C]formaldehyde in the presence of microsomes was described by an apparent KM(1) and Vmax(1) of 0.16 +/- 0.09 mM and 4.1 +/- 2.8 nmol HCHO/min/mg protein (mean +/- SD; N = 5 different livers), respectively,(More)
Seratrodast (ABT-001, AA-2414) undergoes cytochrome P450 (CYP)-dependent metabolism to a major (5-methylhydroxy seratrodast; 5-HOS) and a minor 4'-hydroxy seratrodast metabolite in human liver microsomes. The mean apparent K(m) and Vmax for the formation of 5-HOS were 15.5 microM and 589.0 pmol 5-HOS formed/mg protein/min, respectively. Chemical inhibition(More)
The activity of human liver microsomal cytochrome P450 1A2 (CYP1A2) is readily estimated by following the O-deethylation of [O-ethyl 14C]phenacetin (PODase). The basis of the assay is the quantitative measurement of [14C]acetaldehyde, remaining in the supernatant of assay incubates, after extraction of unmetabolized [O-ethyl 14C]phenacetin with charcoal. In(More)