Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

A Randomized Trial of Intravenous Amino Acids for Kidney Protection

Background Acute kidney injury (AKI) is a serious and common complication of cardiac surgery, for which reduced kidney perfusion is a key contributing factor. Intravenous amino acids increase kidney perfusion and recruit renal functional reserve. However, the efficacy of amino acids in reducing the occurrence of AKI after cardiac surgery is uncertain. Methods In a multinational, double-blind trial, we randomly assigned adult patients who were scheduled to undergo cardiac surgery with cardiopulmonary bypass to receive an intravenous infusion of either a balanced mixture of amino acids, at a dose of 2 g per kilogram of ideal body weight per day, or placebo (Ringer's solution) for up to 3 days. The primary outcome was the occurrence of AKI, defined according to the Kidney Disease: Improving Global Outcomes creatinine criteria. Secondary outcomes included the severity of AKI, the use and duration of kidney-replacement therapy, and all-cause 30-day mortality. Results We recruited 3511 patients at 22 centers in three countries and assigned 1759 patients to the amino acid group and 1752 to the placebo group. AKI occurred in 474 patients (26.9%) in the amino acid group and in 555 (31.7%) in the placebo group (relative risk, 0.85; 95% confidence interval [CI], 0.77 to 0.94; P=0.002). Stage 3 AKI occurred in 29 patients (1.6%) and 52 patients (3.0%), respectively (relative risk, 0.56; 95% CI, 0.35 to 0.87). Kidney-replacement therapy was used in 24 patients (1.4%) in the amino acid group and in 33 patients (1.9%) in the placebo group. There were no substantial differences between the two groups in other secondary outcomes or in adverse events. Conclusions Among adult patients undergoing cardiac surgery, infusion of amino acids reduced the occurrence of AKI

From old-style interactive datasets on the Euring domain to an onthology-driven open hypermedia

The Euring community collects an impressive body of data about marked animals to address queries connected directly with the biology of populations and individuals. Further knowledge is needed as well to specify and constrain the values of complex biological data stored in its national and sub-national federated databases

Long-term voluntary ethanol consumption induces impairment of the mechanical performance in the papillary muscle of Sardinian alcohol-preferring rats

he effects of chronic (26 weeks) ethanol consumption on cardiac muscle contractility in Sardinian alcohol-preferring drinkers (sP-D) and Sardinian alcohol-preferring naive (sP-N) rats were investigated. Experiments were carried out 1 week after ethanol administration ceased. Length-tension and force-frequency responses in left ventricular papillary muscles from both sP-D and sP-N rats were recorded in vitro. Papillary muscles were gradually stretched in steps of 5% of the reference (initial) length (L-r) from 100 to 130% L-r. In sP-D rats, length-tension relationships showed a significant reduction in active tension: at optimal length for maximum active tension (130% L-r), the developed force value (1.38 +/- 0.36 mN/mg, dry tissue) was 54% lower than that found in sP-N rats (3.16 +/- 0.6 mN/mg, dry tissue). In sP-D papillary muscles, a decrease in contractile behaviour was also observed in force-frequency responses (0.03-120 pulse/min), when compared with sP-N rats; developed force was found to be reduced by about 2.5 times. These results indicate that long-term ethanol consumption impairs the mechanical performance of sP papillary muscle, inducing a negative inotropic effect

Integrazione di impianti fotovoltaici con sistemi di accumulo ACAES per incrementare l’autoconsumo di energia dei piccoli centri urbani

Questo studio analizza le prestazioni di un impianto fotovoltaico (FV) integrato con un sistema di accumulo ad aria compressa adiabatico (ACAES), al fine di incrementare l’autoconsumo energetico di piccoli centri urbani. Come caso studio è stato considerato un centro abitato di circa 10000 abitanti e diverse soluzioni per il sistema integrato PV-ACAES. I risultati mostrano come il sistema integrato possa incrementare dal 47 % al 62 % la quota di autoconsumo energetico del centro urbano.This paper evaluates the performance of a photovoltaic (PV) power plant integrated with an Adiabatic Compressed Air Energy Storage (ACAES) system, designed to increase the energy self-consumption rate of a small town. As case study, a small town of about 10000 inhabitants and different PV-ACAES power plants have been considered. The results demonstrate that the integrated system allows to increase from 47% to 62% the energy self-consumption rate of the town