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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Methods: Day 3 to day 7 after admission to a stroke unit, 64 persons with stroke were assessed twice, using the SwePASS, by two physiotherapists. Inter-rater reliability was determined using percentage-agreement and the rank-invariant method: relative position, relative concentration, and relative rank variance.
Results: The raters showed a percentage agreement of ≥75% in the assessments using the SwePASS. For 9 of the 12 items, the percentage agreement was >80%. For 8 of the 12 items, there was a statistically significant change in position, revealed in relative position values between 0.08 and 0.15. Three items had statistically significant positive relative concentration values between ?0.11 and 0.10. Except for a statistically significant negligible relative variance value of 0.01 for the items 1 and 8, there was no relative variance.
Conclusions: The SwePASS shows an acceptable inter-rater reliability, albeit with potential for improvement. The reliability can be improved by a consensus how to interpret the scale between the raters prior to implementation in the clinic. 相似文献