Publications by authors named "J C Tonkyn"

Introduction: Tafenoquine has been recently registered for the prevention of relapse in Plasmodium vivax malaria.

Objective: This study assessed the pharmacodynamic effects of 300-mg single-dose tafenoquine on the retina.

Methods: This phase I, prospective, multicenter, randomized, single-masked, placebo-controlled, parallel-group study was conducted between 2 February 2016 and 14 September 2017 at three US study centers.

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This first-time-in-human (FTIH) study evaluated the safety, tolerability, pharmacokinetics, and food effect of single and repeat oral doses of GSK3036656, a leucyl-tRNA synthetase inhibitor. In part A, GSK3036656 single doses of 5 mg (fed and fasted), 15 mg, and 25 mg and placebo were administered. In part B, repeat doses of 5 and 15 mg and placebo were administered for 14 days once daily.

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We characterized the relationship between the plasma concentration of the phospodiesterase (PDE)-4 inhibitor GSK356278 and occupancy of the PDE4 enzyme in the brain of healthy volunteers, using the positron emission tomography (PET) tracer [C](R)-rolipram. To this end, PET scans were acquired in eight male volunteers before and at 3 and 8 h after a single 14 mg oral dose of GSK356278. A metabolite-corrected arterial input function was used in conjunction with the dynamic PET emission data to estimate volumes of distribution (V) from a two-tissue compartment model.

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During clinical trials of a tumour necrosis factor (TNF)-R1 domain antibody (dAb™) antagonist (GSK1995057), infusion reactions consistent with cytokine release were observed in healthy subjects with high levels of a novel, pre-existing human anti-VH (HAVH) autoantibody. In the presence of HAVH autoantibodies, GSK1995057 induced cytokine release in vitro due to binding of HAVH autoantibodies to a framework region of the dAb. The epitope on GSK1995057 was characterized and dAbs with reduced binding to HAVH autoantibodies were generated; pharmacological comparability was determined in human in-vitro systems and in-vivo animal experiments.

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The chloroplast S10 ribosomal protein operon is partially duplicated in many plants because it initiates within the inverted repeat of the circular chloroplast genome. In spinach, the complete S10 operon (S10B) spans the junction between inverted repeat B (IRB) and the large single-copy (LSC) region. The S10 operon is partially duplicated in the inverted repeat A (IRA), but the sequence of S10A completely diverges from S10B at the junction of S10A and the LSC region.

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