A comparative assessment of the 48-h acute toxicity of aqueous nanoparticles synthesized using the same methodology, including Au, Ag, and Ag-Au bimetallic nanoparticles, was conducted to determine their ecological effect in freshwater environments through the use of Daphnia magna, using their mortality as a toxicological endpoint. D. magna are one of the standard organisms used for ecotoxicity studies due to their sensitivity to chemical toxicants. Particle suspensions used in toxicity testing were well-characterized through a combination of absorbance measurements, atomic force or electron microscopy, flame atomic absorption spectrometry, and dynamic light scattering to determine composition, aggregation state, and particle size. The toxicity of all nanoparticles tested was found to be dose and composition dependent. The concentration of Au nanoparticles that killed 50% of the test organisms (LC(50)) ranged from 65-75 mg/L. In addition, three different sized Ag nanoparticles (diameters = 36, 52, and 66 nm) were studied to analyze the toxicological effects of particle size on D. magna; however, it was found that toxicity was not a function of size and ranged from 3-4 μg/L for all three sets of Ag nanoparticles tested. This was possibly due to the large degree of aggregation when these nanoparticles were suspended in standard synthetic freshwater. Moreover, the LC(50) values for Ag-Au bimetallic nanoparticles were found to be between that of Ag and Au but much closer to that of Ag. The bimetallic particles containing 80% Ag and 20% Au were found to have a significantly lower toxicity to Daphnia (LC(50) of 15 μg/L) compared to Ag nanoparticles, while the toxicity of the nanoparticles containing 20% Ag and 80% Au was greater than expected at 12 μg/L. The comparison results confirm that Ag nanoparticles were much more toxic than Au nanoparticles, and that the introduction of gold into silver nanoparticles may lower their environmental impact by lowering the amount of Ag which is bioavailable.

Transcatheter aortic valve implantation (TAVI) is a rapidly evolving therapeutic modality currently available for patients with severe aortic stenosis (AS) that are unsuitable for surgery because of technical/anatomical issues or high-estimated surgical risk. Transfemoral approach is the preferred TAVI delivery route when possible. Alternative non-transfemoral access options include transaortic, trans-subclavian and transapical access. Other approaches are also feasible (transcarotid, transcaval, and antegrade aortic) but are restricted to operators and hospitals with experience. The peculiarities of each of the vascular approaches designed for TAVI delivery make it necessary to carefully assess patient's atherosclerotic load and location, arterial size and tortuosity, and presence of mural thrombus. Several clinical trials are currently ongoing and in the near future the indications for these approaches will likely be better defined and extended to a broader spectrum of TAVI candidates.

Early unenhanced CT alone was a good indicator of severity of acute pancreatitis in our selected population. CT grade was sensitive for predicting outcome in acute pancreatitis. Pancreatic necrosis, estimated on early, contrast-enhanced CT and seen only in patients having severe disease, was a specific predictor of morbidity and mortality. These findings lead us to suggest that the use of iodinated contrast material to assess necrosis can be reserved for only those patients classified as having severe disease on unenhanced CT.

Background: In recent years, the use of surgically implanted biological aortic valves has been favored over mechanical prosthesis in patients between 50 and 70 years of age. However, outcomes on long-term survival are contradictory. The objective of this study was to determine if patients with mechanical valves have worse long-term survival than patients with biological prostheses.Methods: We systematically searched published studies that: (1) were propensity score-matched or randomized controlled trials; (2) provided survival data with a minimum follow-up of 5 years; and (3) included patients older than 50 and younger than 70 years of age. Review articles, case reports, and editorials were excluded. We conducted a meta-analysis on the basis of 2 types of analysis. A reconstruction of the database of each study to simulate a patient-level meta-analysis was performed. Log rank test of Kaplan-Meier curves was recalculated. Hazard ratio (HR) was calculated using a univariate Cox regression. In addition, we calculated a pooled HR using the fixed-effect inverse variance method.Results: Four propensity score-matched studies and 1 randomized controlled trial met the inclusion criteria. Data of 4686 patients were analyzed. Survival rates for mechanical versus biological valves at 10 and 15 years of follow-up were: 76.78% (95% confidence interval [CI], 74.72%-78.69%) versus 74.09% (95% CI, 71.96%-76.08%), and 61.58% (95% CI, 58.29%-64.69%) versus 58.04% (95% CI, 54.57%-61.35%). Log rank test was statistically significant (P ¼ .012) and the pooled HR was 0.86 (95% CI, 0.76-0.97; P ¼ .01).Conclusions: Compared with biological aortic valves, mechanical valves are associated with a long-term survival benefit for patients between 50 and 70 years.

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Introduction: The life expectancy of patients who undergo ascending aortic replacement is unknown. The life expectancy of a population depends on a collection of environmental and socio-economic factors of the territory where they reside. Our aim was to compare the life expectancy of patients undergoing surgery for ascending aortic aneurysm with that of the general population matching by age, sex, and territory. In addition, we aimed to know the late complications, causes of death and risk factors. Methods: All patients who underwent elective replacement of an ascending aortic aneurysm at our institution between 2000 and 2019 were included. The long-term survival of the sample was compared with that of the general population using data of the National Institute of Statistics. Results: For patients who survived the postoperative period, observed cumulative survival at three, five and eight years was 94.07% (95% CI 91.87–95.70%), 89.96% (95% CI 86.92–92.33%) and 82.72% (95% CI 77.68–86.71%). Cumulative survival of the general population at three, five and eight years was 93.22%, 88.30%, and 80.27%. Cancer and cardiac failure were the main causes of death. Conclusions: Long-term survival of patients undergoing elective surgery for ascending aortic aneurysm who survive the postoperative period completely recover their life expectancy.

Moderate PPM appears to be a strong and independent predictor of cardiac events and advanced functional class in young and middle-aged patients undergoing AVR for severe stenosis. However, it is possible that it has no impact on overall mortality.

The prevalence of patient-prosthesis mismatch using the Trifecta aortic prosthesis is extraordinary low. This finding may have great clinical repercussions in patients undergoing surgical aortic valve replacement.