It is unknown, however, where compensatory vesicle retrieval is localized in this cell type and by what mechanism(s) excess membrane is recaptured. To determine whether endocytosis is localized or diffuse in mouse bipolar neurons, we imaged FM4-64 to track vesicles in cells whose synaptic ribbons were tagged with EGFR inhibitor a fluorescent
peptide. In synaptic terminals, vesicle retrieval occurred at discrete sites that were spatially consistent over multiple stimuli, indicative of endocytotic “”hot spots.”" Retrieval sites were spatially correlated with fluorescently labeled synaptic ribbons. Electron microscopy (EM) analysis of bipolar cell terminals after photoconversion of internalized FM dye revealed that almost all of the dye was contained within vesicles similar to 30 nm in diameter. Clathrin-coated vesicles were observed budding from the plasma membrane and within the cytosol, and application of dynasore, a dynamin inhibitor, arrested membrane retrieval just after the budding stage. We conclude that synaptic vesicles in the fine branches of mouse bipolar axon terminals are retrieved
locally near active zones, at least in part via a clathrin-mediated pathway. (C) 2009 IBRO. Published by Elsevier Ltd. All rights reserved.”
“Background. This study was designed to evaluate the benefits of InVEST (increased Velocity Specific to Task) training find more on limb power and mobility union, mobility-limited older adults.
Methods. We conducted a single
blinded, Apoptosis antagonist randomized controlled trial among 138 mobility-limited community dwelling older adults, evaluating two 16-week supervised exercise programs. The intervention group participated in InVEST training, and the control group participated in the National Institute on Aging’s (NIA) strength training program. primary outcomes were changes in limb power per kilogram and mobility performance as measured by the Short physical performance Battery (SPPB).
Results. After 16 week, InVEST produced significantly greater improvements in limb power than NIA (p = .02) There was no significant difference in strength improvements. Both groups had significant changes in SPPB of greater than I Unit. Self-reported function was also significantly improved in both groups. Differences between groups were not statistically different. In a post hoc analysis when participants were categorized by the manifestation of baseline leg velocity impairments (N = 68). InVEST training produced effect size differences in SPPB that were clinically meaningful (SPPB Group x Time difference 0.73 units, p = .05).
Conclusions. Among mobility-limited older adults, both NIA and InVEST produce robust changes in observed physical performance and self-reported function. These improvements were not meaningfully different by statistical clinical criteria. Compared with NIA, InVEST training produced greater improvements in limb power and equivalent improvements in strength.