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The use of extracorporeal membrane oxygenator instead of standard cardiopulmonary bypass during lung transplantation is debatable. Moreover, recently, the concept of prolonged postoperative extracorporeal membrane oxygenator (ECMO) support has been introduced in many transplant centers to prevent primary graft dysfunction (PGD) and improve early and long-term results. The objective of this study was to review the results of our extracorporeal life support strategy during and after bilateral sequential lung transplantation (BSLT) for pulmonary artery hypertension. We review retrospectively our experience in BSLT for pulmonary artery hypertension between January 2010 and August 2018. A total of 38 patients were identified. Nine patients were transplanted using cardiopulmonary bypass (CPB), in eight cases CPB was followed by a prolonged ECMO (pECMO) support, 14 patients were transplanted on central ECMO support, and seven patients were transplanted with central ECMO support followed by a pECMO assistance. The effects of different support strategies were evaluated, in particular in-hospital morbidity, mortality, incidence of PGD, and long-term follow-up. The use of CPB was associated with poor postoperative results and worse long-term survival compared with ECMO-supported patients. Predictive preoperative factors for the need of intraoperative CPB instead of ECMO were identified. The pECMO strategy had a favorable effect to mitigate postoperative morbidity and mortality, not only in intraoperative ECMO-supported patients, but even in CPB-supported cases. In our experience, ECMO may be considered as the first choice circulatory support for lung transplantation. Sometimes, in very complex cases, CBP is still necessary. The pECMO strategy is very effective to reduce incidence of PGD even in CPB-supported patients.  相似文献   
96.

Purpose

The research questions of the present study were: (1) Is total knee prosthesis wear behaviour influenced by implant size, body weight and their combined effect? (2) Are these findings significant and helpful from a clinical point of view?

Methods

Two very different sizes of the same total knee prosthesis (TKP), previously tested with ISO 14243 parameters, were tested on a knee simulator for a further two million cycles using a modified ISO 14243 load waveform. Roughness examination was performed on the metallic components. Gravimetric and micro-Raman spectroscopic analyses were carried out on the polyethylene inserts.

Results

The average volumetric mass loss was 69 ± 3 mm3 and 88 ± 4 mm3 for smaller and bigger size, respectively. Bigger TKPs are little influenced by an increased load, while the wear trend of the smaller TKP showed a redoubled slope, and more significant morphology changes were observed. However, the two sizes seem to behave similarly when subjected to a load increase of 15 %; the slope of the volumetric mass loss trend was comparable for the two sets of inserts, which did not appear significantly different also at the molecular level. Roughness average parameters of the lateral femoral condyle support this evidence.

Conclusions

It can be asserted that the body weight and implant size are relevant to the understanding of TKP wear behaviour. A post-implantation body weight increase in a patient with smaller knee dimensions could results in more critical effects on prosthesis long-term performance.  相似文献   
97.

Objective

Breast-conserving surgery has become the preferred treatment for early breast cancer. Yet the question of what constitutes a ‘safe margin’, in terms of impact on patient outcome, remains unanswered. Our aim was to address this knowledge gap by determining the prevalence of positive and narrow margins after breast-conserving surgery, and evaluating how margin status impacted local recurrence and overall survival.

Materials and Methods

We collected data about all women who underwent breast-conserving cancer surgery in our department between 2002 and 2011, focusing on patient and tumor characteristics, the distance from the tumor to the surgical margin, therapies administered, and outcome (measured in terms of local recurrence and overall survival). Data were analyzed by R (version 3.0.1), considering p < 0.05 as significant. Multivariate analyses were also performed.

Results

Of 1,192 women who received breast-conserving surgery, 264 were considered for widening; 111 of these patients had positive margins and 153 narrow (where narrow was defined as less than 5 mm). Widening was performed for 38 % of these patients (99/264) and mastectomy for 27 % (70/264), while 36 % (95/264) had no further surgery and were simply followed-up. Our multivariate analysis confirmed that local tumor recurrence and overall survival were not significantly influenced by margin status, either at initial surgery, or (for those patients with initially positive margins) at secondary margin-widening surgery. However, the following were found to be significantly correlated with local recurrence: tumor multifocality, high expression of Ki-67/Mib-1, comedo-like necrosis, and non-axillary lymph node positivity (p < 0.05).

Conclusions

We found the status of resection margins and the management of infiltrated or narrow margins to have no significant influence on local tumor recurrence rates or on overall patient survival. Instead, biological factors connected with tumor aggressiveness seem to play the most important role in breast cancer prognosis, independent of surgical radicality.  相似文献   
98.
Journal of Interventional Cardiac Electrophysiology - The purpose of the study was to evaluate the impact of left atrial posterior wall isolation (LAPWI) in addition to pulmonary vein isolation...  相似文献   
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Erythropoiesis is triggered by hypoxia and is strictly regulated by hormones, growth factors, cytokines, and vitamins to ensure an adequate oxygen delivery to all body cells. Abnormalities in one or more of these factors may induce different kinds of anemia requiring different treatments. A key player in red blood cell production is erythropoietin. It is a glycoprotein hormone, mainly produced by the kidneys, that promotes erythroid progenitor cell survival and differentiation in the bone marrow and regulates iron metabolism. A deficit in erythropoietin synthesis is the main cause of the normochromic normocytic anemia frequently observed in patients with progressive chronic kidney disease. The present review summarizes the most recent findings about each step of the erythropoietic process, going from the renal oxygen sensing system to the cascade of events induced by erythropoietin through its own receptor in the bone marrow. The paper also describes the new class of drugs designed to stabilize the hypoxia-inducible factor by inhibiting prolyl hydroxylase, with a discussion about their metabolism, disposition, efficacy, and safety. According to many trials, these drugs seem able to simulate tissue hypoxia and then stimulate erythropoiesis in patients affected by renal impairment. In conclusion, the in-depth investigation of all events involved in erythropoiesis is crucial to understand anemia pathophysiology and to identify new therapeutic strategies, in an attempt to overcome the potential side effects of the commonly used erythropoiesis-stimulating agents.  相似文献   
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