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Roberto V.P. Ribeiro Mitesh V. Badiwala Danny Ramzy Laura C. Tumiati Vivek Rao 《The Journal of thoracic and cardiovascular surgery》2019,157(2):615-625.e1
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84.
《Ultrasound in medicine & biology》2015,41(12):3172-3181
Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy. 相似文献
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目的探讨参麦注射液联合米力农治疗难治性心力衰竭的临床效果。方法选择难治性心力衰竭患者92例,依据随机数字的方法分为对照组46例和观察组46例,患者入院后均常规治疗,对照组给予米利农治疗,观察组在对照组治疗方法基础上给予参麦注射液。对两组治疗前后的心型脂肪酸结合蛋白(H-FABP),血浆心肌肌钙蛋白Ⅰ(cTnⅠ),氨基末端B型钠尿肽原(NT-proBNP),心率(HR),左心室射血分数(LVEF),每搏输出量(SV)进行对比。对两组的临床治疗效果进行对比。对两组治疗过程中的不良反应对比。结果经过治疗后,对照组的H-FABP从(17.23±3.51)ng/L降低到(15.11±3.12)ng/L,NT-proBNP从(8.13±2.32)μg/L降低到(6.51±1.45)μg/L,cTnⅠ从(31.25±5.01)ng/L降低到(23.81±4.25)ng/L,观察组的H-FABP从(16.97±3.78)ng/L降低到(9.91±3.01)ng/L,NT-proBNP从(8.21±1.98)μg/L降低到(4.13±1.34)μg/L,cTnⅠ从(32.07±5.23)ng/L降低到(18.81±5.12)ng/L,观察组的变化幅度大于对照组,数据差异均具有统计学意义(t=8.135,8.176,5.096,P<0.05),经过治疗后,对照组的HR从(135.26±10.51)次/min降低到(103.81±9.81)次/min,LVEF从(32.41±5.41)%升高到(38.31±4.87)%,SV从(37.91±2.71)mL升高到(43.23±3.47)mL,观察组的HR从(134.81±11.28)次/min降低到(95.31±9.97)次/min,LVEF从(31.87±5.37)%升高到(43.21±4.25)%,SV从(38.11±3.13)mL升高到(50.91±3.68)mL,观察组的变化幅度大于对照组,数据差异均具有统计学意义(t=4.122,-5.142,-10.298,P<0.05),观察组的治疗效果优于对照组,数据差异具有统计学意义(z=-4.994,P<0.05),两组的恶心[4.35%(2/46)VS. 2.17%(1/46)],血压低[6.52%(3/46)VS. 4.35%(2/46)],头晕[8.70%(4/46)VS. 13.04%(6/46)],乏力[15.22%(7/46)VS. 8.70%(4/46)],呕吐[4.35%(2/46)VS. 6.52%(3/46)],室性早搏[2.17%(1/46)VS. 4.35%(2/46)],发生率数据差异均不具有统计学意义(χ^2=0.000,0.000,0.449,0.929,0.000,0.000,P>0.05)。结论利用参麦注射液联合米力农治疗难治性心力衰竭,可以改善心肌功能,提升治疗效果,安全性良好。 相似文献
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《Patient education and counseling》2020,103(4):854-863
ObjectiveTo examine the effectiveness of a nurse-led multidisciplinary self-management program (NMSP) on self-management behaviors, self-efficacy, health-related quality of life (HRQoL) and unplanned health service utilization (HSU) among Chinese patients with coronary heart disease (CHD) in communities.MethodsA randomized controlled trial with repeated measurements was used. A convenience sample of 144 participants was recruited from a community health center in China. All participants were randomly assigned to an intervention group (n = 72) in the newly developed NMSP or a control group (n = 72) in routine care. Outcome measurement was performed at baseline, 3 months and 6 months using Coronary Artery Disease Self-Management Scale (CADSs), Self-efficacy for Chronic Disease 6-item Scale (SECD6), and Short Form-12 health survey questionnaire (SF-12).ResultsOver the six months, the two groups reported significant differences in disease medical and emotional management of CADSs, confidence in symptom and disease management of SECD6, physical and mental component summary of SF-12, as well as emergency and outpatient visits of unplanned HSU.ConclusionsThe NMSP improves self-management behaviors, self-efficacy, HRQoL and reduces unplanned HSU among CHD patients in communities.Practice implicationsThis study provides an effective approach to empower CHD patients with emphasizing on collaboration support of health professionals in communities. 相似文献
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