The effect of ischemic preconditioning on the free-radical state of isolated rat myocardium fixed by rapid freezing at the 25th min of normothermic total ischemia and the 3rd min of reperfusion was studied by the EPR method. It was shown that EPR spectra registered at -40 degrees C consist of two free-radical signals: of the semireduced forms of ubiquinone and flavine coynzymes. It was found that during ischemia and at the beginning of reperfusion, the preconditioning results in a narrowing of the spectra (as compared with control) due to an increase in the narrow ubisemiquinone EPR signal portion, and a decrease in the total concentration of free-radical centers: by 16% in the case of ischemia, and 23% in the case of reperfusion. It was concluded that in both cases the changes were due to a decrease in the concentration of myocardial flavosemiquinones as a result of ischemic preconditioning. We registered the microvawe power saturation curves for these two stages, which corresponded to control and ischemic preconditioning. In the case of ischemia these dependences had similar shapes; however, in the case of reperfusion they differ from each other due to changes in the relative intensities of the EPR signals from ubisemiquinone and flavosemiquinones in the integral myocardial free-radical spectra.
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Background And Purpose: To investigate the impact of a history of ischemic stroke or transient ischemic attack (TIA) on the effectiveness of remote ischemic conditioning (RIC) for outcomes in acute ischemic stroke patients.
Methods: We conducted a post hoc analysis of the Remote Ischaemic Conditioning for Acute Moderate Ischaemic Stroke (RICAMIS) trial. Patients in RICAMIS were categorized into two groups according to a history of stroke.
Acta Cir Bras
January 2025
Universidad Nacional de La Plata - Faculty of Medicine - Organ Transplant Laboratory - La Plata - Argentina.
Purpose: To mitigate ischemia-reperfusion injury (IRI) triggered in solid organ transplant procedures, we aimed to evaluate the effects of multi-organ abdominal ischemic preconditioning (MAIP) in the context of renal IRI.
Methods: An experimental kidney transplant model was conducted. Rats were divided into three groups: an intervention free basal group from which physiological data was collected; a control group (CT), which consisted of transplanted animals without MAIP; and a treated group, in which a MAIP protocol was implemented in the donor during the procurement of the left kidney, monitoring the recipient for 24 hours.
Exp Brain Res
January 2025
Faculty of Sport, Technology and Health Sciences, St. Mary's University, Twickenham, Middlesex, UK.
The aim of this study was to assess if ischaemic preconditioning (IPC) can reduce pain perception and enhance corticospinal excitability during voluntary contractions. In a randomised, within-subject design, healthy participants took part in three experimental visits after a familiarisation session. Measures of pressure pain threshold (PPT), maximum voluntary isometric force, voluntary activation, resting twitch force, corticospinal excitability and corticospinal inhibition were performed before and ≥10 min after either, unilateral IPC on the right leg (3 × 5 min); a sham protocol (3 × 1 min); or a control (no occlusion).
View Article and Find Full Text PDFFront Med (Lausanne)
December 2024
Department of Anesthesiology, The 988th Hospital of Joint Logistic Support Force of Chinese People's Liberation Army, Zhengzhou, China.
Objective: Limb ischemia-reperfusion injury caused by repeated tourniquet application usually leads to acute kidney injury, adversely affecting patient prognosis. This study aimed to investigate the renoprotective effect of remote ischemic preconditioning (RIPC) in patients undergoing extremity surgery with repeated tourniquet application.
Methods: 64 patients were enrolled and randomly divided into an RIPC group and a control group, with 32 patients in each.
Cardiovasc Drugs Ther
January 2025
The Hatter Cardiovascular Institute, University College London, 67 Chenies Mews, London, WC1E 6HX, UK.
Purpose: Reperfusion of the ischaemic heart is essential to limit myocardial infarction. However, reperfusion can cause cardiomyocyte hypercontracture. Recently, cardiac myosin-targeted inhibitors (CMIs), such as Mavacamten (MYK-461) and Aficamten (CK-274), have been developed to treat patients with cardiac hypercontractility.
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