Bradley C. Johnston

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The role of the multidrug resistance protein MRP4/ABCC4 in vivo remains undefined. To explore this role, we generated Mrp4-deficient mice. Unexpectedly, these mice showed enhanced accumulation of the anticancer agent topotecan in brain tissue and cerebrospinal fluid (CSF). Further studies demonstrated that topotecan was an Mrp4 substrate and that cells(More)
BACKGROUND Antibiotic treatment may disturb the resistance of gastrointestinal flora to colonization. This may result in complications, the most serious of which is Clostridium difficile–associated diarrhea (CDAD). PURPOSE To assess the efficacy and safety of probiotics for the prevention of CDAD in adults and children receiving antibiotics. DATA(More)
BACKGROUND Clinicians find standardized mean differences (SMDs) calculated from continuous outcomes difficult to interpret. Our objective was to determine the performance of methods in converting SMDs or means to odds ratios of treatment response and numbers needed to treat (NNTs) as more intuitive measures of treatment effect. METHODS(More)
The 4-anilinoquinazoline (4-AQ) derivative gefitinib (Iressa) is an oral epidermal growth factor receptor tyrosine kinase inhibitor. Oral administration of 4-AQ molecules, such as gefitinib, inhibits ATP-binding cassette (ABC) transporter-mediated drug efflux and strongly increases the apparent bioavailability of coadministered drug molecules that are(More)
Presenting continuous outcomes in Summary of Findings tables presents particular challenges to interpretation. When each study uses the same outcome measure, and the units of that measure are intuitively interpretable (e.g., duration of hospitalization, duration of symptoms), presenting differences in means is usually desirable. When the natural units of(More)
IMPORTANCE The discontinuation of randomized clinical trials (RCTs) raises ethical concerns and often wastes scarce research resources. The epidemiology of discontinued RCTs, however, remains unclear. OBJECTIVES To determine the prevalence, characteristics, and publication history of discontinued RCTs and to investigate factors associated with RCT(More)
IMPORTANCE Many claims have been made regarding the superiority of one diet or another for inducing weight loss. Which diet is best remains unclear. OBJECTIVE To determine weight loss outcomes for popular diets based on diet class (macronutrient composition) and named diet. DATA SOURCES Search of 6 electronic databases: AMED, CDSR, CENTRAL, CINAHL,(More)
BACKGROUND Patients across North America are using complementary and alternative medicine (CAM) with increasing frequency as part of their management of many different health conditions. The objective of this study was to develop a guide for academic health sciences centers that may wish to consider starting an integrative medicine program. METHODS We(More)
BACKGROUND Antibiotics are widely prescribed; however they can cause disturbances in gastrointestinal flora which may lead to reduced resistance to pathogens such as Clostridium difficile (C. difficile). Probiotics are live organisms thought to balance the gastrointestinal flora. OBJECTIVES The primary objectives were to assess the efficacy and safety of(More)
BACKGROUND Spinal manipulation is a noninvasive manual procedure applied to specific body tissues with therapeutic intent. Although spinal manipulation is commonly used in children, there is limited understanding of the pediatric risk estimates. OBJECTIVE Our goal was to systematically identify and synthesize available data on adverse events associated(More)