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Background: Remote ischemic conditioning (RIC) by brief periods of limb ischemia and reperfusion protects against ischemia–reperfusion injury. We studied the cardioprotective role of extracellular vesicles (EV)s released into the circulation after RIC and EV accumulation in injured myocardium. Methods: We used plasma from healthy human volunteers before and after RIC (pre-PLA and post-PLA) to evaluate the transferability of RIC. Pre- and post-RIC plasma samples were separated into an EV enriched fraction (pre-EV + and post-EV +) and an EV poor fraction (pre-EV- and post-EV-) by size exclusion chromatography. Small non-coding RNAs from pre-EV + and post-EV + were purified and profiled by NanoString Technology. Infarct size was compared in Sprague–Dawley rat hearts perfused with isolated plasma and fractions in a Langendorff model. In addition, fluorescently labeled EVs were used to assess homing in an in vivo rat model. (ClinicalTrials.gov, number: NCT03380663) Results: Post-PLA reduced infarct size by 15% points compared with Pre-PLA (55 ± 4% (n = 7) vs 70 ± 6% (n = 8), p = 0.03). Post-EV + reduced infarct size by 16% points compared with pre-EV + (53 ± 15% (n = 13) vs 68 ± 12% (n = 14), p = 0.03). Post-EV- did not affect infarct size compared to pre-EV- (64 ± 3% (n = 15) and 68 ± 10% (n = 16), p > 0.99). Three miRNAs (miR-16-5p, miR-144-3p and miR-451a) that target the mTOR pathway were significantly up-regulated in the post-EV + group. Labelled EVs accumulated more intensely in the infarct area than in sham hearts. Conclusion: Cardioprotection by RIC can be mediated by circulating EVs that accumulate in injured myocardium. The underlying mechanism involves modulation of EV miRNA that may promote cell survival during reperfusion. [ABSTRACT FROM AUTHOR]

A dynamic model for an inclined carbon fiber reinforced polymer (CFRP) cable is established, and the linear and nonlinear dynamic behaviors are investigated in detail. The partial differential equations for both the in-plane and out-of-plane dynamics of the inclined CFRP cable are obtained by Hamilton's principle. The linear eigenvalues are explored theoretically. Then, the ordinary differential equations for analyzing the dynamic behaviors are obtained by the Galerkin integral and dimensionless treatments. The steady-state solutions of the nonlinear equations are obtained by the multiple scale method (MSM) and the Newton-Raphson method. The frequency- and force-response curves are used to investigate the dynamic behaviors of the inclined CFRP cable under simultaneous internal (between the lowest in-plane and out-of-plane modes) and external resonances, i.e., the primary resonances induced by the excitations of the in-plane mode, the out-of-plane mode, and both the in-plane mode and the out-of-plane mode, respectively. The effects of the key parameters, e.g., Young's modulus, the excitation amplitude, and the frequency on the dynamic behaviors, are discussed in detail. Some interesting phenomena and results are observed and concluded. [ABSTRACT FROM AUTHOR]

Describes the method of numerical simulation on solidification process of horizontally continuously cast round iron bars in China. Factors influencing the calculation of heat transfer; Distribution of heat flux; Determination of thermal conductivity of air gap.