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71.
Livers from donors after circulatory death (DCD) are a promising option to increase the donor pool, but their use is associated with higher complication rate and inferior graft survival. Normothermic machine perfusion (NMP) keeps the graft at 37°C, providing nutrients and oxygen supply. Human liver stem cell-derived extracellular vesicles (HLSC-EVs) are able to reduce liver injury and promote regeneration. We investigated the efficacy of a reconditioning strategy with HLSC-EVs in an experimental model of NMP. Following total hepatectomy, rat livers were divided into 4 groups: (i) healthy livers, (ii) warm ischemic livers (60 min of warm ischemia), (iii) warm ischemic livers treated with 5 × 108 HLSC-EVs/g-liver, and (iv) warm ischemic livers treated with a 25 × 108 HLSC-EVs/g-liver. NMP lasted 6 h and HLSC-EVs (Unicyte AG, Germany) were administered within the first 15 min. Compared to controls, HLSC-EV treatment significantly reduced transaminases release. Moreover, HLSC-EVs enhanced liver metabolism by promoting phosphate utilization and pH self-regulation. As compared to controls, the higher dose of HLSC-EV was associated with significantly higher bile production and lower intrahepatic resistance. Histologically, this group showed reduced necrosis and enhanced proliferation. In conclusion, HLSC-EV treatment during NMP was feasible and effective in reducing injury in a DCD model with prolonged warm ischemia.  相似文献   
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Annals of Surgical Oncology - The liver-first approach in patients with synchronous colorectal liver metastases (CRLM) has gained wide consensus but its role is still to be clarified. We aimed to...  相似文献   
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Medial tibial stress syndrome (MTSS) is one of the most common lower leg injuries in sporting populations. It accounts for between 6 and 16% of all running injuries, and up to 53% of lower leg injuries in military recruits. Various treatment modalities are available with varying degrees of success. In recalcitrant cases, surgery is often the only option. To evaluate whether ultrasound-guided injection of 15% dextrose for treatment of recalcitrant MTSS decreases pain and facilitates a return to desired activity levels for those who may otherwise be considering surgery or giving up the sport. The study design was a prospective consecutive case series involving eighteen patients: fifteen male and three female; (mean age = 31.2 years) with recalcitrant MTSS. They were referred from sports injury clinics across the UK, having failed all available conservative treatment. An ultrasound-guided sub-periosteal injection of 15% dextrose was administered by the same clinician (NP) along the length of the symptomatic area. Typically, 1 mL of solution was injected per cm of the symptomatic area. Pain was assessed using a 10-cm visual analog scale (VAS) at baseline, short-term, medium-term (mean 18 weeks), and long-term (mean 52 weeks) follow-up. Symptom resolution and return to activity were measured using a Likert scale at medium and long-term follow-up. Statistical analyses were performed using SPSS for Mac version 19.0.0 (IBM, New York, NY, US). The Shapiro-Wilk test was used to evaluate the normality of the distribution of data. Friedman’s non-parametric test was used to compare the within-patient treatment response over time. Post-hoc Wilcoxon signed-rank tests with Bonferroni corrections were performed to determine VAS average pain response to treatment over five paired periods. Patients reported a significant (p < 0.01) reduction in median VAS pain score at medium and long-term follow-up compared to baseline. Median improvement per patient was 4.5/10. Patients rated their condition as ‘much improved’ at medium-term follow-up and the median return to sports score was ‘returned to desired but not pre-injury level’ at medium-term and long-term follow-up. No adverse events were reported. Ultrasound-guided 15% dextrose prolotherapy injection has a significant medium-term effect on pain in MTSS. This benefit may be maintained long-term; however, more robust trials are required to validate these findings in the absence of controls. Clinicians should consider the use of ultrasound-guided injection of 15% dextrose as a viable treatment option to reduce pain and aid return to activity for patients with recalcitrant MTSS.  相似文献   
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BackgroudCurrent evidence supports the use of cemented hemiarthroplasty for treatment of intracapsular femoral neck fractures since it is associated with a lower risk of implant-related complications. However, many medical centers employ the cementless technique for the frail elderly population because it is faster and has lower cardiovascular risks and perioperative mortality. This observational study reports the outcomes of cementless bipolar hemiarthroplasty for intracapsular femoral neck fractures in patients aged 80 years and older.MethodsA total of 424 patients (female, 77.1%) with a mean age of 86.9 years were operated for intracapsular femoral neck fractures between January 2009 and December 2017. Of those, 66.7% had an American Society of Anaesthesiologists (ASA) score of 3 or more. All operations were performed with the posterolateral surgical approach and all patients received a cementless stem. Intraoperative and perioperative values and in-hospital outcomes were evaluated, and clinical and radiographical follow-up was done at 40 days, 90 days, and when possible between 5 months and 12 months postoperatively. Multivariate analysis was performed to evaluate if there were factors affecting mortality.ResultsThe mean operative time was 50 minutes. There were no deaths intraoperatively. Intraoperative periprosthetic fractures occurred in 2.1% of the cases with 66.7% of them fixed through cerclage wires intraoperatively. The median length of hospitalization was 11 days (interquartile range, 8.75–15) and 2.4% of patients died while in hospital after surgery. Approximately 91.5% of patients presented with perioperative anemia. Only 1.9% of the complications were related to the implant, 62.5% of which were dislocations. More than 90% of patients were ambulatory either autonomously or with support at each follow-up assessment. Age, male sex, and higher ASA score were related to increased mortality.ConclusionsDespite some limitations, this observational study underlines that a cementless femoral stem of modern design can give good clinical outcomes, thus being an appropriate solution especially for the frail elderly.  相似文献   
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By means of injecting soot into the vessels of the uveal tract of the rabbit eye the character of changes in the architectonics of the vascular bed in dynamics of the burn process could be detected. It was found that a burn trauma produces changes in practically the whole uveal tract, but to a greater extent, in its anterior segment. Reduction of blood filling of the vessels or their total segmentary "switching-off" is connected with the development of reversible (thrombosis, oedema of endotheliocytes and surrounding stroma, hemolysis) and irreversible (destruction of the vascular wall, obliteration of vessels) structural changes. The degree of disturbances in blood circulation and reversibility of these changes depend on the severity of the burn. In case of less severe burns, total structural restoration of the vascular network in the nearest time is recorded, while in severe burns--partial restoration with elements of vascular net reconstruction of adaptive character.  相似文献   
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During the last century, the reduction of birth and all-cause mortality rates have resulted in an increase in the life expectancy and the proportion of the elderly population in many countries. For example, elderly women represent more than 16% and elderly men comprise more than 12% of the population in Italy. The health consequences of these demographic shifts in population is important, because older people experience reductions in some physiologic functions and in increased incidence of chronic, mainly cardiovascular, diseases. Data derived from a survey of men between the ages of 71 and 91 years, who are the survivors of the original rural samples of the Italian section of the Seven Countries Study, show the large contribution of cardiovascular diseases to the long list of chronic conditions. The indicators of self-sufficiency, dementia, and of the self-perception of poor health proved much more common among subjects with cardiovascular diseases than in those with other chronic conditions.  相似文献   
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