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Patients with polyvascular disease (PVD), involving two or more vascular beds, are a difficult group for cardiologists, cardiovascular surgeons and endovascular surgeons. The relevance of the problem is due to its widespread prevalence, rapid progression, and comorbidity, which worsens the prognosis in this cohort of patients. The problem of selecting the optimal revascularization tactics remains unresolved. The results of original research on this problem are analyzed. The need for an individual multidisciplinary approach to determine the best revascularization strategy is demonstrated. The use of various methods of optimal therapy, open and endovascular surgery in each specific case is the most acceptable tactic.

Among many versions of methods for the chromatographic separation of substances, to date, insufficient attention has been paid to their continuous separation. Among a few exceptions is a review by Maryutina and Spivakov published in 2001 [4]. Our paper deals with a more detailed consideration of the attempts made for the continuous chromatographic separation of substances and the assessment of the efficiency of the solutions found. The aim of this review was to draw more attention to this promising direction for solving two interrelated problems. First, to creating systems for the continuous analytical control of complex multicomponent samples of the composition changing with time, and, second, to solving preparative and technological problems of the separation of substances with similar chemical properties. In the first case, the method ensures studies of the dynamics of changes in the composition of complex multicomponent mixtures in studying fast chemical processes, and, when used for technological purposes, it opens up a possibility of the continuous chemical-analytical monitoring of their course from the standpoint of economic efficiency and safety. In the second case, methods of continuous chromatographic separation ensure an increase in the efficiency and productivity of obtaining valuable high-purity substances., Author(s): L. N. Moskvin [sup.1] , A. E. Kostanyan [sup.2] , A. L. Moskvin [sup.3] , O. V. Rodinkov [sup.1] , N. M. Yakimova [sup.1] Author Affiliations: (1) grid.15447.33, 0000 [...]

Objetivos: O vírus sincicial respiratório (VSR) pode causar doença respiratória grave em adultos mais velhos com problemas cardiorrespiratórios. Em um estudo controlado por placebo de fase 3 em andamento (NCT04886596), a eficácia da vacina (VE) RSVPreF3 OA durante a primeira temporada de VSR foi de 82,6% contra doenças do trato respiratório inferior relacionadas ao VSR (RSV-LRTD), e 71,7% contra doenças respiratórias agudas relacionadas ao VSR (RSV-ARI) em adultos com ≥60 anos de idade. Apresentamos a VE em participantes com condições cardiorrespiratórias coexistentes de interesse associadas a um risco maior de desfechos graves da doença por VSR. Métodos: Adultos com ≥60 anos foram randomizados 1:1 e receberam 1 dose de vacina RSVPreF3 OA ou placebo. A VE foi avalida contra primeiros episódios de RSV-LRTD e RSV-ARI em subgrupos de interesse específico. Resultados: Dos 12.467 pacientes que receberam a vacina RSVPreF3 OA e 12.499 pacientes que receberam placebo, um total de 20,0% e 19,4%, respectivamente, tinham ≥ 1 condição cardiorrespiratória de interesse. As taxas de incidência de RSV-LRTD e RSV-ARI foram maiores no grupo placebo com ≥1 condição cardiorrespiratória de interesse versus aqueles sem nenhuma condição médica de interesse. A VE foi de 92,1% para prevenir RSV-LRTD, e 88,1% para RSV-ARI. Conclusões: RSVPreF3 OA foi eficaz contra RSV-LRTD e RSV-ARI em adultos com ≥ 60 anos de idade com condições cardiorrespiratórias de interesse, sendo essa provavelmente a população que mais pode se beneficiar da proteção contra VSR. ENCORE: este é um ENCORE de um resumo apresentado na ERS 2023.

This article is devoted to a brief review of the modelling of liquid membrane separation methods, such as emulsion, supported liquid membranes, film pertraction, and three-phase and multi-phase extraction. Mathematical models and comparative analyses of liquid membrane separations with different flow modes of contacting liquid phases are presented. A comparison of the processes of conventional and liquid membrane separations is carried out under the following assumptions: mass transfer is described by the traditional mass transfer equation; the equilibrium distribution coefficients of a component passing from one of the phases to another are constant. It is shown that, from the point of view of mass transfer driving forces, emulsion and film pertraction liquid membrane methods have advantages over the conventional conjugated extraction stripping method, when the mass-transfer efficiency of the extraction stage is significantly higher than the efficiency of the stripping stage. The comparison of the supported liquid membrane with conjugated extraction stripping showed that when mass-transfer rates on the extraction and stripping sides are different, the liquid membrane method is more efficient, while when they are equal to each other, both processes demonstrate the same results. The advantages and disadvantages of liquid membrane methods are discussed. The main disadvantages of liquid membrane methods—low throughput and complexity—can be overcome by using modified solvent extraction equipment to carry out liquid membrane separations.

Pseudo-liquid membranes are extraction devices in which a liquid membrane phase is retained in an apparatus consisting of two interconnected chambers while feed and stripping phases pass through the stationary liquid membrane phase as mobile phases. The organic phase of the liquid membrane sequentially contacts the aqueous phases of the feed and stripping solutions in the extraction and stripping chambers, recirculating between them. This extraction separation method, called multiphase pseudo-liquid membrane extraction, can be implemented using traditional extraction equipment: extraction columns and mixer-settlers. In the first case, the three-phase extraction apparatus consists of two extraction columns connected at the top and bottom by recirculation tubes. In the second case, the three-phase apparatus consists of a recycling close-loop, which includes two mixer-settler extractors. In this study, the extraction of copper from sulfuric acid solutions in two-column three-phase extractors was experimentally studied. A 20% solution of LIX-84 in dodecane was used as the membrane phase in the experiments. It was shown that the extraction of copper from sulfuric acid solutions in the apparatuses studied was controlled by the interfacial area in the extraction chamber. The possibility of the purification of sulfuric acid wastewaters from copper using three-phase extractors is shown. To increase the degree of extraction of metal ions, it is proposed to equip two-column three-phase extractors with perforated vibrating discs. To further increase the efficiency of extraction using the pseudo-liquid membrane method, it is proposed to use multistage processes. The mathematical description of multistage three-phase pseudo-liquid membrane extraction is discussed.