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Open in a separate window OBJECTIVESFew data exist on the use of del Nido cardioplegia in adults, specifically during operations requiring prolonged aortic cross-clamp. In this pilot study, we evaluate outcomes of patients undergoing surgery with cross-clamp time >3 h based on re-dosing strategy, using either full dose (FD; 1:4 blood to crystalloid ratio) or dilute (4:1 blood to crystalloid ratio) solution.METHODSConsecutive adult patients (>18 years) undergoing cardiac surgery from 2012 to 2018 with cross-clamp time >3 h were reviewed. Patients were excluded if del Nido cardioplegia was not used. Patients were categorized into FD or dilute groups based on re-dosing solution. Propensity score matching was used to control for baseline differences between groups. The primary endpoint was in-hospital mortality. Other outcomes examined included: postoperative mechanical support, arrhythmia, stroke, dialysis and cardiac function.RESULTSIncluded for analysis were 173 patients (115 male) with median age of 63.8 (interquartile range 53.9–73.1). Major comorbidities included diabetes (45), cerebrovascular disease (34), hypertension (131), atrial fibrillation (52) and previous cardiac surgery (83). There were 108 patients (62%) who received FD re-dosing, while 65 (38%) received dilute. A greater proportion of patients in the dilute group received retrograde delivery, for both induction (32/108 vs 39/65, P <0.001) and re-dose (50/108 vs 53/65, P <0.001). After propensity score matching, in-hospital mortality was not different between groups (6/48 vs 1/48, P =0.131). There were no differences in rates of postoperative mechanical circulatory support, stroke, left ventricular ejection fraction or right ventricle dysfunction.CONCLUSIONSDel Nido cardioplegia has been used in complex cardiac surgery requiring prolonged cross-clamp. Re-dosing can be performed with either FD or dilute del Nido solution with no statistical difference in outcomes.  相似文献   
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BackgroundTo evaluate the association between COVID-19 vaccination and retinal vein occlusion (RVO).MethodsThis multicentre self-controlled case series included patients with RVO seen in five tertiary referral centres in Italy. All adults who received at least one dose of the BNT162b2, ChAdOx1 nCoV-19, mRNA-1273 or Ad26.COV2.S vaccine and had a first diagnosis of RVO between January 01, 2021, and December 31, 2021 were included. Incidence rate ratios (IRRs) of RVO were estimated using Poisson regression, comparing rates of events in a 28-day period following each dose of vaccination and in the unexposed control periods.Results210 patients were included in the study. No increased risk of RVO was observed after the first dose (1–14 days IRR: 0.87, 95% CI: 0.41–1.85; 15–28 days IRR: 1.01, 95% CI: 0.50–2.04; 1–28 days IRR: 0.94, 95% CI: 0.55–1.58) and second dose of vaccination (1–14 days IRR: 1.21, 95% CI: 0.62–2.37; 15–28 days IRR: 1.08, 95% CI: 0.53–2.20; 1–28 days IRR: 1.16, 95% CI: 0.70–1.90). No association between RVO and vaccination was found in subgroup analyses by type of vaccine, gender and age.ConclusionsThis self-controlled case series found no evidence of an association between RVO and COVID-19 vaccination.Subject terms: Retinal diseases, Epidemiology  相似文献   
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Mesenchymal stem cells (MSCs) from bone marrow (BM) and sub-cutaneous fat are known to differentiate into neural cells under appropriate stimuli. We describe here the neural-like differentiation of human MSCs obtained from spleen and thymus, induced either with chemical factors or with co-culture with human Schwann cells (Sc). Under the effect of neural differentiation medium, most MSCs from BM, fat, spleen and thymus acquired morphological changes suggestive of cells of astrocytic/neuronal and oligodendroglial lineages with general up-regulation of neural molecules not correlated with morphological changes. The process was transient and reversible, as MSCs recovered basal morphology and phenotype, as well as their multilineage differentiation potential. Thus, we hypothesized that chemical factors may prime MSCs for neural differentiation, by inducing initial and poorly specific changes. By contrast, co-cultures of MSCs of different origin with Sc induced long-lasting and Sc differentiation, i.e., the expression of Sc myelin proteins for up to 12 days. Our results show that a MSC reservoir is present in tissues other than BM and fat, and that MSCs of different origin have similar neural differentiation potential. This evidence provides new insights into BM-like tissue plasticity and may have important implications for future therapeutic interventions in chronic neuropathies.  相似文献   
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Since elderly patients are being referred for surgery in increasing numbers, we reviewed the clinical outcome of 459 consecutive patients aged 70 to 89 years, who had aortic valve replacement between 1993 and 2000. We subdivided the study population into three groups: in Group 1 we included patients aged 70-74 years old; in Group 2 patients aged 75-79 years old; and in Group 3 patients aged 80 years old or older. An isolated AVR was performed in 289 patients (63%), concomitant coronary artery bypass graft (CABG) in 168 patients (36.6%), an isolated ventricular septal defect (VSD) closure in one patient (0.2%) and an isolated atrial septal defect (ASD) closure in one patient (0.2%). The overall perioperative mortality rate was 7% (32 patients), without significant differences among the three groups (P=0.88). Our study confirms the good outcome of aortic valve replacement in elderly patients even in octagenarians and only concomitant CABG procedures increase the operative risk, reducing long-term survival (P<0.05).  相似文献   
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COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors’ liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

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