Articles: function.
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Transient voltage-gated sodium currents are essential for the initiation and conduction of action potentials in neurons and cardiomyocytes. The amplitude and duration of sodium currents are tuned by intracellular fibroblast growth factor homologous factors (FHFs/iFGFs) that associate with the cytoplasmic tails of voltage-gated sodium channels (Na v s), and genetic ablation of Fhf genes disturbs neurological and cardiac functions. ⋯ Here, we use electrophysiological and computational methods to show that the heat nociception deficit can be explained by the combined effects of elevated temperature and FHF2 deficiency on the fast inactivation gating of Na v 1.7 and tetrodotoxin-resistant sodium channels expressed in dorsal root ganglion C fibers. Hence, neurological and cardiac heat-associated deficits in Fhf2null mice derive from shared impacts of FHF deficiency and temperature towards Na v inactivation gating kinetics in distinct tissues.
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The purpose of this study was to further our understanding of early childhood pain-related distress regulation. Concurrent and predictive relations between child-led emotion regulation (ER) behaviors and pain-related distress during vaccination were examined at 2 different ages using autoregressive cross-lagged path analyses. Toddlers were video-recorded at the 12- and 18-month routine vaccination appointments (12-month-old [N = 163]; 18-month-old [N = 149]). ⋯ Physical self-soothing was significantly related to less pain-related distress at both ages. Taken together, these findings suggest that disengagement of attention and physical self-soothing may serve more of a regulatory function during toddlerhood, whereas parent-focused behaviors may serve more of a function of gaining parent support for regulation. This study is the first to assess these relations during routine vaccination in toddlerhood and suggests that toddlers in the second year of life are beginning to play a bigger role in their own regulation from painful procedures than earlier in infancy.
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Neuronal N-type (Ca V 2.2) voltage-gated calcium channels are essential for neurotransmission from primary afferent terminals in the dorsal horn. In this study, we have used a knockin mouse containing Ca V 2.2 with an inserted extracellular hemagglutinin tag (Ca V 2.2_HA), to visualise the pattern of expression of endogenous Ca V 2.2 in dorsal root ganglion (DRG) neurons and their primary afferents in the dorsal horn. We examined the effect of partial sciatic nerve ligation (PSNL) and found an increase in Ca V 2.2_HA only in large and medium dorsal root ganglion neurons and also in deep dorsal horn synaptic terminals. ⋯ We also found that following PSNL, there is patchy loss of glomerular synapses immunoreactive for Ca V 2.2_HA and CGRP or IB4, restricted to the superficial layers of the dorsal horn. This reduction is not dependent on α 2 δ-1 and likely reflects partial deafferentation of C-nociceptor presynaptic terminals. Therefore, in this pain model, we can distinguish 2 different events affecting specific DRG terminals, with opposite consequences for Ca V 2.2_HA expression and function in the dorsal horn.
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Randomized Controlled Trial
Effects of Implementation of a Supervised Walking Program in Veterans Affairs Hospitals : A Stepped-Wedge, Cluster Randomized Trial.
In trials, hospital walking programs have been shown to improve functional ability after discharge, but little evidence exists about their effectiveness under routine practice conditions. ⋯ U.S. Department of Veterans Affairs Quality Enhancement Research Initiative (Optimizing Function and Independence QUERI).
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Clinical Trial
Dynamic cerebral autoregulation during step-wise increases in blood pressure during anaesthesia: A nonrandomised interventional trial.
Classically, cerebral autoregulation (CA) entails cerebral blood flow (CBF) remaining constant by cerebrovascular tone adapting to fluctuations in mean arterial pressure (MAP) between ∼60 and ∼150 mmHg. However, this is not an on-off mechanism; previous work has suggested that vasomotor tone is proportionally related to CA function. During propofol-based anaesthesia, there is cerebrovascular vasoconstriction, and static CA remains intact. Sevoflurane-based anaesthesia induces cerebral vasodilation and attenuates CA dose-dependently. It is unclear how this translates to dynamic CA across a range of blood pressures in the autoregulatory range. ⋯ During general anaesthesia, dynamic CA is dependent on MAP, also within the autoregulatory range. This phenomenon was more pronounced during propofol anaesthesia than during sevoflurane.