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51.

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   
52.
ObjectiveHigh fluctuations in injury-risk during the playing season in soccer have been reported. As seasons are structured in periods with homogenous loads and intensities, we investigated injury-risk over season periods, contrarily to previous studies adopting a month-based approach.DesignCohort study; Level of evidence, 2.MethodsIncidence-rate ratios (IRRs) for match and training injuries were compared across six consecutive seasons of German Bundesliga, divided into six periods each: Pre-season (PS), winter-break (WB), quarter 1–4: (Q1–Q4).ResultsSignificant variations in injury-risk were observed for match and training injuries. IRRs in matches was 1.30 (95% CI: 1.11–1.53) times higher in Q3 and 1.53 (95% CI: 1.31–1.78) higher in Q4 compared to Q1. For training injuries, IRR peaked in Q1 and Q3 followed by a marked decrease in each subsequent quarter. Compared to Q4, IRR was 1.62 (95% CI: 1.40–1.86) times higher during Q3 and 1.78 (95% CI: 1.53–2.07) times higher in Q1. IRR was significantly higher in the competitive season compared to pre-season across match (IRR: 2.00, 95% CI: 1.30–3.00) and training (IRR: 1.27, 95% CI: 1.11–1.43) injuries.ConclusionsThe increased match IRRs later during the season indicate that, in practice, coaches should consider putting even more emphasis on recovery in the last part of the season. Moreover, training injuries seem to indicate a carry-over effect. Further studies need to investigate how training during preparatory phases can be implemented in a way that prevents injuries during the competitive season.  相似文献   
53.
Context: We sought to describe our experience with the Hybrid Assistive Limb® (HAL®) for active knee extension and voluntary ambulation with remaining muscle activity in a patient with complete paraplegia after spinal cord injury.

Findings: A 30-year-old man with complete paraplegia used the HAL® for 1 month (10 sessions) using his remaining muscle activity, including hip flexor and upper limb activity. Electromyography was used to evaluate muscle activity of the gluteus maximus, tensor fascia lata, quadriceps femoris, and hamstring muscles in synchronization with the Vicon motion capture system. A HAL® session included a knee extension session with the hip flexor and voluntary gait with upper limb activity. After using the HAL® for one month, the patient’s manual muscle hip flexor scores improved from 1/5 to 2/5 for the right and from 2/5 to 3/5 for the left knee, and from 0/5 to 1/5 for the extension of both knees.

Conclusion/clinical relevance: Knee extension sessions with HAL®, and hip flexor and upper-limb-triggered HAL® ambulation seem a safe and feasible option in a patient with complete paraplegia due to spinal cord injury.  相似文献   

54.
Objectives: There is a paucity of reporting on surgical outcomes of isolated posterior cruciate ligament reconstruction (PCLR). We hypothesize that isolated PCL injuries failing nonoperative treatment achieve good outcomes and are able to return to sport following PCLR.

Methods: A retrospective analysis was performed to identify patients with isolated PCL injuries that underwent reconstruction between 2001 and 2014. Patients with multi-ligamentous injury or another concomitant knee pathology were excluded. Medical records were reviewed for demographic, clinical and operative data. Patients were contacted for administration of a telephone-based questionnaire which included the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation form, Lysholm-Tegner scales, Marx activity scale (MAS), return to sport status, and patient satisfaction instruments.

Results: A total of 15 isolated PCL reconstructions in 14 patients with a mean age of 27.5 years (range 17–43) met the study inclusion criteria; mean follow up was 6.3 years (range 1.4–15.2). Pre-operatively, the primary complaint was knee instability in all patients; on physical examination, lack of a firm end point during posterior drawer testing was found in 93% (14/15) of the knees. In total, 12 of 15 knees underwent transtibial, single-bundle PCLR and three of 15 underwent tibial inlay, double bundle PCLR. Graft types included: quadriceps autograft (7/15), Achilles allograft (6/15), and hamstring autograft (2/15). There were no graft failures in our patient cohort. At most recent follow up the mean scores respectively on the IKDC form, Lysholm-Tegner scales and MAS were (standard deviation): 77.3 (16.5), 83.1 (17.9), 6.13 (2.6), and 7.1 (6.0). All fourteen patients were athletes prior to their injury and 79% (11/14) returned to sport and overall patient satisfaction was 9.2/10.

Conclusions: Isolated PCLR provides good outcomes at mean medium-term follow up with restoration of function, high rate of return to sport and overall patient satisfaction.  相似文献   

55.
目的 探讨N-乙酰-5-羟色胺(N-acetylserotonin,NAS)对视网膜缺血-再灌注损伤(retina ischemia-reperfusion injury,RIRI)大鼠视网膜Fas、FasL蛋白表达的影响。方法 取健康成年Sprague Dawley大鼠54只,将大鼠随机分为正常组(6只)、RIRI组(24只)与NAS组(24只);采用高眼压法建立大鼠RIRI模型,依据造模后不同时间点将RIRI组与NAS组大鼠又分为6 h、12 h、24 h及72 h四个亚组。NAS组于造模前30 min腹腔注射NAS(5 mg·kg-1),RIRI组腹腔注射等剂量的生理盐水。通过HE染色在光学显微镜下观察各组大鼠视网膜形态学变化,并记录各组大鼠视网膜厚度及视网膜神经节细胞数,采用免疫组织化学染色法检测NAS对RIRI大鼠视网膜Fas、FasL蛋白表达的影响。结果 HE染色显示,正常组大鼠视网膜各层细胞分界清晰,形态正常,神经细胞排列整齐;RIRI组大鼠再灌注后6 h视网膜各层出现水肿,以神经节细胞层及内核层较显著,神经节细胞数较正常组减少;随后视网膜水肿进一步加重,神经节细胞继续减少;NAS组大鼠在再灌注后6 h、12 h、24 h 视网膜水肿程度较 RIRI组轻,NAS组在再灌注后72 h视网膜厚度较 RIRI组厚,NAS组各时间点神经节细胞数均较 RIRI组多,差异均有统计学意义(均为P<0.05)。免疫组织化学染色显示,正常组几乎未见 Fas+细胞。再灌注后6 h,RIRI组视网膜神经节细胞及内核层开始出现少量 Fas+细胞;再灌注后12 h,RIRI组视网膜 Fas+细胞表达逐渐增多;再灌注后24 h视网膜Fas+细胞数达到高峰,棕色阳性染色细胞分布在视网膜神经节细胞层、内丛状层、内核层及神经纤维层;再灌注后 72 h 视网膜 Fas+细胞较再灌注后 24 h 减少。NAS组在再灌注后6 h、12 h、24 h、72 h 视网膜 Fas+细胞数均较 RIRI组各时间点减少,再灌注后24 h,Fas+细胞数达较高水平,随后下降,差异均有统计学意义(均为P<0.05)。正常组视网膜可见 FasL 全层低表达。RIRI组再灌注后 6 h,视网膜神经节细胞层和神经纤维层存在少量 FasL+细胞;再灌注后12 h FasL蛋白表达逐渐增多;再灌注后24 h FasL+细胞数达高峰,可见深棕色的细胞膜及细胞质染色细胞分布在视网膜神经节细胞层、内丛状层、内核层及神经纤维层;再灌注后72 h FasL蛋白的阳性表达逐渐减少。NAS组再灌注后6 h、12 h、24 h、72 h 视网膜FasL+细胞数均少于 RIRI组各时间点阳性细胞数,差异均有统计学意义(均为P<0.05)。结论 NAS可通过抑制RIRI大鼠视网膜细胞Fas、FasL蛋白的表达,减轻缺血再灌注对大鼠视网膜细胞造成的损伤。  相似文献   
56.
A multitude of athletic injuries occur when the various tissues that make up the human body experience stresses and strains that exceed their material strength. The precise amount of stress and strain that any given tissue can withstand is determined by the mechanical properties and resultant strength of that particular tissue. These mechanical properties are directly determined by an individual’s physiology and acute regulation of these properties. A number of theoretical frameworks for athletic injury occurrence have been proposed, however, a detailed conceptual framework for injury aetiology that considers the interplay between the physiological and mechanical factors and outlines the causal pathways to tissue damage and injury is needed. This will guide injury research towards a more thorough investigation of causal mechanisms and understanding of risk factors. Further, it is important to take into account the considerable differences in loading patterns which can result in varying injury outcomes such as acute stress-related, strain-related, or overuse injury. Within this article a simplified conceptual model of athletic injury is proposed along with a detailed, evidence-informed, conceptual framework for athletic injury aetiology that focuses on stress-related, strain-related, and overuse injury.  相似文献   
57.
Objective: The objective of this study was to gain greater insight into individuals’ quality of life (QOL) definitions, appraisals, and adaptations following spinal cord injury (SCI).

Design: A mixed-methods design, applying the Schwartz and Sprangers response shift (RS) model. RS is a cognitive process wherein, in response to a change in health status, individuals change internal standards, values, or conceptualization of QOL

Setting: Community-dwelling participants who receive medical treatment at a major Midwestern medical system and nearby Veterans’ Affairs hospital.

Participants: A purposive sample of participants with SCI (N?=?40) completed semi-structured interviews and accompanying quantitative measures.

Interventions: Not applicable.

Outcome Measures: Qualitative data were analyzed using content analysis to identify themes. Analysis of variance were performed to detect differences based on themes and QOL, well-being, and demographic and injury characteristics.

Results: Four RS themes were identified, capturing the range of participant perceptions of QOL. The themes ranged from complete RS, indicating active engagement in maintaining QOL, to awareness and comparisons redefining QOL, to a relative lack of RS. Average QOL ratings differed as a function of response shift themes. PROMIS Global Health, Anxiety, and Depression also differed as a function of RS themes.

Conclusion: The RS model contextualizes differences in QOL definitions, appraisals, and adaptations in a way standardized QOL measures alone do not.  相似文献   

58.
目的探究临床用乌司他丁辅助治疗重症感染性休克的治疗效果。方法90例重症感染性休克患者,随机分为观察组与对照组,每组45例。对照组患者采用西医常规治疗,观察组患者在对照组基础上联合乌司他丁治疗。比较两组患者治疗效果、体温情况、感染情况以及治疗前后白细胞计数、白细胞介素-6(IL-6)水平、格拉斯哥昏迷量表(GCS)评分、急性生理功能和慢性健康状况评分系统Ⅱ(APACHEⅡ)评分。结果治疗后,观察组白细胞计数(7.34±1.32)×10^9/L低于对照组的(9.41±1.16)×10^9/L,差异具有统计学意义(P<0.05)。治疗后,观察组高热、感染体征发生率分别为97.78%、86.67%,均高于对照组的82.22%、62.22%,差异具有统计学意义(P<0.05);观察组体温恢复时间、感染消失时间分别为(7.19±1.39)、(3.88±0.89)d,均短于对照组的(9.81±1.88)、(10.76±1.57)d,差异具有统计学意义(P<0.05)。观察组患者血清IL-6为(4.27±0.95)μg/L低于对照组的(9.58±1.07)μg/L,差异具有统计学意义(P<0.05)。观察组患者GCS评分和APACHEⅡ评分较治疗前均有所改善,GCS评分(8.19±1.59)分、APACHEⅡ评分(8.83±0.82)分均优于对照组的(6.81±1.82)、(14.71±3.52)分,差异均具有统计学意义(P<0.05)。观察组患者治疗总有效率95.56%明显高于对照组的77.78%,差异具有统计学意义(χ^2=6.154,P<0.05)。结论乌司他丁具有较好的抗炎效果,与西医治疗相结合可以提高临床疗效,加快重症感染性休克患者退热速度,缩短感染时间,降低白细胞计数及血清IL-6水平,改善GCS评分和APACHEⅡ评分,临床疗效较好。  相似文献   
59.
Inflammation plays a critical role in the development of ventilator-induced lung injury (VILI). Endoplasmic reticulum (ER) stress is associated with a variety of diseases through the modulation of inflammatory responses. However, little is known about how ER stress is implicated in VILI. In this study, murine mechanical ventilation models were constructed. Total protein and inflammatory cytokines were measured in bronchoalveolar lavage fluid (BALF), and lung tissue injury was assessed by histology. Our data revealed that mice subjected to high tidal ventilation (TV) for 4 h showed more severe pulmonary edema and inflammation than those of mice with spontaneous breathing and low TV-treatment. In addition, the high TV-treated animals upregulated the ER stress markers GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB expression at both the mRNA and protein levels in lung tissue. Administration of thapsigargin exacerbated the histological changes, inflammation and expression of GRP78 and CHOP after high TV, but treatment with ER stress and IRE1α kinase inhibitors attenuated the pathological damage and downregulated the high expression of GRP78, CHOP, p-IRE1α, TRAF2, and p-NF-κB, suggesting that ER stress is involved in VILI though the IRE1α/TRAF2/NF-κB signaling pathway in mice.  相似文献   
60.
ObjectivesThis study aimed to validate the skin temperature on sacral region and vascular attributes as early warning signs of pressure injury.MethodsTotally 415 patients admitted to the adult intensive care unit from August 2018 to April 2019 were prospectively screened. Daily blood pressure and blood glucose affecting vascular attributes and the relative skin temperature of sacral region were measured for 10 consecutive days. Collect the changes of these indicators during the occurrence of pressure injury. The optimal cut-off values of indicators were determined by X-tile analysis. The risk ratios of indicators associated with pressure injury were compared using the Cox proportional hazards regression model.ResultsThere were no obvious interactions among blood pressure, blood glucose and relative skin temperature (P > 0.05). The optimal cutoff value for above indicators was 63.5 mmHg, 9.9 mmol/L and −0.1 °C, respectively. The incidence of pressure injury peaked on the 4th and 5th day after hospitalization when categorizing the patients into low- and high-risk groups according to the cutoff values (P < 0.05). Based on relative skin temperature, patients in the high-risk group were more likely to develop pressure injury (hazard ratio = 6.36, 95% confidence interval = 3.91, 10.36), when compared to the other two indicators of blood pressure and blood glucose.ConclusionStringent skin temperature and vascular attributes measurements were necessary for preventing pressure injury. Nursing measures should be taken according to warning sings to reduce the incidence of pressure injury.  相似文献   
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