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Background and Aims Dialytic clearance of protein-bound toxins and large middle molecules is poor by diffusive treatment and limited by high-flux hemodialysis (HD) and on-line hemodiafiltration (OL-HDF), and only a few studies have examined how to improve their removal by other extracorporeal strategies. Since 2017, there is a new generation of polymethyl methacrylate (PMMA) membranes that suppress platelet adhesion on the membrane surface improving hemocompatibility and permeability, while also maintaining adsorption properties related to conventional PMMA membranes. Expanded HD (HDx) with medium cut-off (MCO) membranes has also recently been incorporated into clinical practice and may improve the removal of uremic toxins in HD treatments. The aim of this pilot study was to compare the efficacy of a new high-flux PMMA dialyzer (Filtryzer® NF-2.1H) in a post-dilution OL-HDF session with a new MCO membrane (Theranova® 400) in a HDx session. Method In an open, cross-over, single-center, controlled, prospective clinical study, 40 adult stable HD patients were assigned to be treated by post-dilution OL-HDF with the NF-2.1H dialyzer or by HDx with the Theranova 400 dialyzer. All other dialysis parameters, including blood and dialysate flow rates, length of dialysis session, and ultrafiltration rate remained unchanged during both sessions. P-cresyl sulfate (PCS), indoxyl sulfate (IS), and kappa (κ) and lambda( λ) free light chains (FLC) reduction rates were intraindividually compared for the two dialyzer types (primary outcomes). Secondary outcomes included the kt and the reduction ratio of blood urea nitrogen, phosphate and β2 -microglobulin (β 2-m). Results The reduction ratio of protein-bound toxins ranges from 60% to 67%, with no differences between membranes (Figure). PMMA membrane achieved greater FLC reduction ratios than MCO membrane, reaching significance for λFLC (56.6% vs. 77.4%; p < 0.001). Conversely, β2M reduction ratio was slightly but significantly higher with MCO membrane (68.5 vs. 72.1%; p = 0.002). Small molecules removal including urea and phosphate were similar in both groups, achieving an optimal Kt with no differences between groups (61.3±9.2 Vs. 59.7±9.3; p=0.16). Albumin reduction ratio tended to be higher with PMMA membrane without reaching significance (10.1±5.9% Vs. 7.8±12.3%; p=0.17). The mean convective volume achieved with PMMA was 23.5±4.4 L. Conclusion This study suggested that new high-flux PMMA dialyzer in post-dilution OL-HDF mode might achieve better FLC reduction ratios than MCO dyalizer in HDx mode, whereas both techniques may equally remove protein-bound toxins. OL-HDF with new PMMA membranes could be a good dialysis strategy for adding convective transport to the well-known mechanisms of diffusion and absorption previously described with conventional PMMA membranes, enabling an adequate substitution volume.

El presente trabajo reflexiona acerca de los retos que el sector editorial en España debe afrontar para adecuar su oferta a las nuevas necesidades y expectativas generadas por los lectores-usuarios en la actual era digital. Partiendo de un cambio en el concepto de textualidad propiciado por los nuevos soportes de lectura, se hace hincapié en las novedades que las ediciones críticas en formato digital deberán aportar para acercar los nuevos contenidos a un público especializado que demanda cada vez más una mayor interacción con el texto y los soportes de lectura. Asimismo, se destaca la importancia de aunar esfuerzos entre los profesionales en el ámbito de la edición textual, la filología y la informática para llegar a un consenso que ponga fin al “caos” reinante en el mundo de la edición crítica digital. El presente trabajo reflexiona acerca de los retos que el sector editorial en España debe afrontar para adecuar su oferta a las nuevas necesidades y expectativas generadas por los lectores-usuarios en la actual era digital. Partiendo de un cambio en el concepto de textualidad propiciado por los nuevos soportes de lectura, se hace hincapié en las novedades que las ediciones críticas en formato digital deberán aportar para acercar los nuevos contenidos a un público especializado que demanda cada vez más una mayor interacción con el texto y los soportes de lectura. Asimismo, se destaca la importancia de aunar esfuerzos entre los profesionales en el ámbito de la edición textual, la filología y la informática para llegar a un consenso que ponga fin al “caos” reinante en el mundo de la edición crítica digital.

The atmospheric reaction between NO and ozone has been investigated using ab initio methods. The structures of all reactants, products, intermediates, and transition states of reaction 1 have been optimized and characterized at the UMP2(full) level of theory. The 6-31G(d), 6-311G(d), and 6-311G(df) basis sets have also been used to calibrate the effect of the basis set functions on the optimized structures and energies of all stationary points. Finally, we have reoptimized at the UMP4(SDQ, full)/6-31G(d) and 6-311G(d) levels. The energetics of the reaction has been studied more accurately within the G2 and G2(MP2) schemes. Also, QCISD(T)/6-311G(d) single-point calculations have been performed by using UMP2(full)/6-31G(d), 6-311G(d), and 6-311G(df) geometries. The mechanism study of the NO + O3 → NO2 + O2 reaction has shown that the transition between reactants and products is not direct, but it proceeds along two transition states (TS1 and TS2) separated by the intermediate (A). There is also the possibil...