Melanie L-S Chan

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BACKGROUND Treatment options for pulmonary arterial hypertension target the prostacyclin, endothelin, or nitric oxide pathways. Tadalafil, a phosphodiesterase type-5 inhibitor, increases cGMP, the final mediator in the nitric oxide pathway. METHODS AND RESULTS In this 16-week, double-blind, placebo-controlled study, 405 patients with pulmonary arterial(More)
It is well established that L-NAME, a generic NOS inhibitor, stimulates neurogenesis in the dentate gyrus of the adult rat and corticosterone reduces it. These experiments explore the interaction between L-NAME and corticosterone. L-NAME (50 mg/kg), as expected, increased proliferation, but also lowered plasma corticosterone levels. However, the stimulating(More)
BACKGROUND Pulmonary arterial hypertension (PAH) is a rare, progressive lung disorder that impairs performance of daily activities and quality of life (QoL), leading to right heart failure and death. Treatment options include prostanoids, endothelin antagonists, and phosphodiesterase type 5 inhibitors (e.g., tadalafil). Currently there is no cure for PAH,(More)
BACKGROUND The subgenual anterior cingulate cortex (sgACC) and its connected circuitry have been heavily implicated in emotional functioning in adolescent-onset major depressive disorder (MDD). While several recent studies have examined sgACC functional connectivity (FC) in depressed youth at rest, no studies to date have investigated sgACC FC in adolescent(More)
OBJECTIVES To determine if baseline characteristics, treatment efficacy, psychosocial outcomes or tolerability were associated with patient preference for sildenafil citrate (sildenafil) or tadalafil for treating erectile dysfunction (ED) in men naive to phosphodiesterase 5 inhibitor therapy. PATIENTS AND METHODS In an open-label, crossover study of(More)
BACKGROUND Functional magnetic resonance imaging research suggests that major depressive disorder (MDD) in both adults and adolescents is marked by aberrant connectivity of the default mode network (DMN) during resting state. However, emotional dysregulation is also a key feature of MDD. No studies to date have examined emotion-related DMN pathology in(More)
Because most men with erectile dysfunction have underlying vascular disease, it is important to update the cardiovascular safety profile of medications used in the treatment of erectile dysfunction. This retrospective analysis evaluated serious cardiovascular treatment-emergent adverse events (CVTEAEs) reported in 36 clinical trials of tadalafil, a(More)
A collection of intergenic suppressors of the Bacillus subtilis spoOF221 mutation has been isolated. One of these suppressors, rvtA, has been mapped between lys-1 and aroD. The rvtA suppressor restores spoOF sporulation to wild type levels and substantially improves the sporulation efficiencies of spoOB and spoOE strains. The rvtA gene does not affect the(More)
OBJECTIVE To examine the preference for 2 dosing regimens (on demand or 3 times/week) for tadalafil, a phosphodiesterase 5 inhibitor with a duration of effectiveness up to 36 hours in men with erectile dysfunction (ED). DESIGN AND METHODS SURE is a 14 European country, multicenter, crossover, and open-label study. Men with ED (N=4262) were randomized to(More)
OBJECTIVE To assess patient and partner preferences for, and satisfaction with, tadalafil or sildenafil (phosphodiesterase type 5 inhibitors) in routine clinical practice for treating erectile dysfunction (ED), as these are important outcomes that might influence treatment adherence. PATIENTS AND METHODS In a multicentre, prospective observational trial(More)