This study presents the first in vivo measurement of transcytolemmal water exchange in the brain using a novel Magnetic Resonance technique. We extend previous applications of Chemical Exchange Saturation Transfer (CEST) to examine water exchange across cellular membranes in late-stage chicken embryo brains. The immature blood-brain barrier at this stage allows Gadolinium-Based Contrast Agents (GBCAs) to penetrate the brain's interstitial space, sensitizing the CEST effect to water exchange between intra- and extracellular environments.
View Article and Find Full Text PDFAnn Intern Med
December 2024
Background: Reported results of clinical trials assessing higher-dose anticoagulation in patients hospitalized for COVID-19 have been inconsistent.
Purpose: To estimate the association of higher- versus lower-dose anticoagulation with clinical outcomes.
Data Sources: Randomized trials were identified from the World Health Organization's International Clinical Trials Registry Platform and ClinicalTrials.
Clinical trials of treatments for stroke have generally utilized 2-arm, randomized designs to evaluate a single intervention against a control. Running separate clinical trials, with each addressing a single therapeutic question, is resource intensive and slows evidence generation, especially in a field with rapidly expanding treatment options and evolving practices. Platform trials-randomized clinical trials designed to evaluate multiple interventions that may enter and exit the ongoing platform based on a master protocol-accelerate the investigation of multiple therapeutic options within a single infrastructure.
View Article and Find Full Text PDFDesigning a clinical trial to evaluate the efficacy of an intervention is often complicated by uncertainty over aspects of the study population, potential treatment effects, most relevant outcomes, dropouts, and other factors. However, once participants begin to be enrolled and partial trial data become available, this level of uncertainty is reduced. Adaptive clinical trials are designed to take advantage of the accumulating data during the conduct of a trial to make changes according to prespecified decision rules to increase the likelihood of success or statistical efficiency.
View Article and Find Full Text PDFFilial imprinting, a crucial ethological paradigm, provides insights into the neurobiology of early learning and its long-term impact on behaviour. To date, invasive techniques like autoradiography or lesions have been used to study it, limiting the exploration of whole brain networks. Recent advances in fMRI for avian brains now open new windows to explore bird's brain functions at the network level.
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