John Ken Gibson

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The efficacy of linezolid, alone or in combination with rifampin, against methicillin-susceptible Staphylococcus aureus in rabbits with experimental endocarditis was investigated. Linezolid (50 or 75 mg/kg of body weight), rifampin, and linezolid (25, 50, or 75 mg/kg) plus rifampin produced statistically significant reductions in bacterial counts compared(More)
Data on New Zealand manufacturing plants are used to examine the impact of trade liberalisation on plant exit. Recent theories suggest that the prospect of a declining market might lead firms to strategic behaviour that causes low cost plants to exit first. This hypothesis is generally unsupported. Surviving plants were larger, lower cost, and were owned by(More)
Vernakalant is a novel antiarrhythmic agent that has demonstrated clinical efficacy for the treatment of atrial fibrillation. Vernakalant blocks, to various degrees, cardiac sodium and potassium channels with a pattern that suggests atrial selectivity. We hypothesized, therefore, that vernakalant would affect atrial more than ventricular effective(More)
The efficacies of orally (p.o.) dosed linezolid and intravenously (i.v.) dosed vancomycin against methicillin-resistant Staphylococcus aureus (MRSA) in rabbits with experimental aortic-valve endocarditis were investigated. After endocarditis was established with a recent clinical MRSA isolate, rabbits were dosed for 5 days with linezolid (p.o., three times(More)
We studied the acute intravenous (i.v.) effects of the antiarrhythmic agents ibutilide, sematilide, lidocaine, and encainide in a canine Y-shaped right atrial incision model of atrial flutter. After baseline determination of atrial effective refractory period (AERP), sustained atrial flutter (AFL) was initiated by atrial pacing in 25 dogs. Each dog then(More)
BACKGROUND Several clinical trials have shown that vernakalant is effective in terminating recent onset atrial fibrillation (AF). The electrophysiological actions of vernakalant are not fully understood. METHODS AND RESULTS Here we report the results of a blinded study comparing the in vitro canine atrial electrophysiological effects of vernakalant,(More)
We studied the effects of orally administered ibutilide, a class III antiarrhythmic agent, in a model of reentrant atrial flutter in conscious dogs. After baseline determination of atrial effective refractory period (AERP) and demonstration of reproducible induction of atrial flutter by rapid atrial pacing, 8 dogs received either placebo or one of six doses(More)
Effects of nadolol, a new beta adrenergic antagonist, were determined on transmembrane potentials of canine Purkinje fibers and ventricular and atrial muscle. Significant alterations in Purkinje fiber potentials occurred only with nadolol concentrations of 10(-4) M or greater. After 1 hour exposure to 10(-4) M, resting potential and action potential(More)
Class III agents have been associated with development of a polymorphic ventricular tachycardia (PVT) known as torsades de pointes. We compared the class III agent ibutilide, which prolongs repolarization through enhancement of an inward sodium current, with the potassium channel blockers E-4031, UK-68,798, clofilium, and D-sotalol for proarrhythmic effects(More)