An Asynchronous Curriculum: Learner Perspectives on Incorporating Asynchronous Learning Into In-Person and Virtual Emergency Residency Didactics.

Background  Didactic education in emergency medicine (EM) residencies has been impacted both by the advent of asynchronous learning and by the shift toward virtual, web-based conference education due to coronavirus disease 2019 (COVID-19). Studies have demonstrated the efficacy of asynchronous education, but few have explored resident opinions about how asynchronous and virtual modifications on conference impact their educational experience.  Objective This study aimed to evaluate resident perceptions of both asynchronous and virtual modifications to a historically in-person didactic curriculum.

Mitochondrial Ca2+ transients in cardiac myocytes during the excitation-contraction cycle: effects of pacing and hormonal stimulation.

Using laser scanning confocal microscopy, our objective was to measure mitochondrial, nuclear, and cytosolic free ionized Ca2+ in adult rabbit cardiac myocytes loaded with Ca2+-indicating fluorophores. When myocytes were loaded with Fluo 3 at 37 degrees C, the fluorophore was loaded extensively into the cytosol and nucleus, but poorly into mitochondria, and Fluo 3 fluorescence transients after field stimulation were confined to the cytosol and nucleus. In contrast, after loading at 4 degrees C, Fluo 3 also entered mitochondria, and large transients of mitochondrial Fluo 3 fluorescence then occurred after stimulation.

Contribution of the mitochondrial permeability transition to lethal injury after exposure of hepatocytes to t-butylhydroperoxide.

We have developed a novel method for monitoring the mitochondrial permeability transition in single intact hepatocytes during injury with t-butylhydroperoxide (t-BuOOH). Cultured hepatocytes were loaded with the fluorescence probes, calcein and tetramethylrhodamine methyl ester (TMRM). Depending on loading conditions, calcein labelled the cytosolic space exclusively and did not enter mitochondria or it stained both cytosol and mitochondria.