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Objective
Hypertonic saline (HTS) has potent immune and vascular effects. We assessed recipient pretreatment with HTS on allograft function in a porcine model of heart transplantation and hypothesized that HTS infusion would limit endothelial and left ventricular (LV) dysfunction following transplantation.Methods
Heart transplants were performed after 6 hours of cold ischemic storage. Recipient pigs were randomized to treatment with or without HTS (7.5% NaCl) before cardiopulmonary bypass (CPB). Using a myograft apparatus, coronary artery endothelial-dependent (Edep) and -independent (Eind) relaxation was assessed. LV performance was determined using pressure-volume loop analysis. Pulmonary interleukin (IL)-2, IL-6, and tumor necrosis factor (TNF)-α expression was measured.Results
Weaning from CPB and LV performance after transplantation were improved in HTS-treated animals. Successful weaning from CPB was greater in the HTS-treated hearts (8 of 8 vs 2 of 8; P < .05). Mean LV functional recovery was improved in the HTS-treated animals, as assessed by preload recruitable stroke work (65 ± 10% vs 27 ± 10%; P < .001) and end-systolic elastance (55 ± 7% vs 37 ± 4%; P < .001). Treatment with HTS resulted in improved Edep (mean maximum elastance [Emax], 56 ± 5% vs 37 ± 7%; P < .001) and Eind (mean Emax%, 77 ± 6% vs 52 ± 4%; P < .001) vasorelaxation compared with control. Pulmonary expression of IL-2, IL-6, and TNF-α increased following transplantation, whereas HTS therapy attenuated IL production (P < .001). Transplantation increased plasma TNF-α levels and LV TNF-α expression, whereas HTS prevented this up-regulation (P < .001).Conclusions
Recipient HTS pretreatment preserves allograft vasomotor and LV function, and HTS therapy limits CPB-induced injury. HTS may be a novel recipient intervention to prevent graft dysfunction. 相似文献Objectives: To examine the effects of the cognitive orientation to daily occupational performance Approach (CO-OP Approach) protocol on occupational performance and satisfaction of Brazilian children who have DCD; to examine whether children could transfer strategies and skills learned during CO-OP to untrained goals.
Methods: A pre-post group comparison design with eight boys aged 6–10 years old. Children participated in 12 CO-OP sessions with their parents twice a week, with an extra session added to the protocol for parents´ orientation. The Canadian Occupational Performance Measure and the Performance Quality Rating Scale were used as outcome measures. The study was registered by the United States Institutes of Health at ClinicalTrials.gov (NCT03112746).
Results: Intervention resulted in higher, clinically and statistically significant, occupational performance measures according to parents, children’s, and external evaluators’ perspectives. All children improved occupational performance on their selected goals and five children could transfer the ability to use cognitive strategies to tasks not addressed in therapy.
Conclusions: This study provides initial directions for future research to investigate the applicability and to implement CO-OP approach on pediatric settings in Brazil. 相似文献