Synthesis of novel 18-crown-6 type ligands containing a phenothiazine 5,5-dioxide unit

Novel crown ethers containing a phenothiazine 5,5-dioxide unit have been synthesized. Macrocyclization reactions rendering N-tosyl protected crown ethers were performed in the absence of metal ion templates. These new crown ethers are useful precursors of sensor and selector molecules with wide applications

Catalytic oxidation of aqueous bioethanol: an efficient upgrade from batch to flow

The heterogeneously catalyzed oxidation of (bio)ethanol to acetic acid is an environmentally friendly alternative to the current industrial Monsanto process. The reaction yields acetic acid from crude bioethanol under mild reaction conditions. The triphasic reaction is technically critical, due to mass and heat transfer limitations and is thus predominantly studied in batch reactor systems. However, in order to advance the industrial implementation of the catalytic route, the operation in flow at the research stage is necessary. It is an efficient, reliable, and safer system for triphasic reactions and allows us to define better performance parameters for a later up-scale of a continuous flow process. Here, we evaluated the aerobic ethanol oxidation in a flow reactor and compared it with a traditional batch system over a gold–titania catalyst under analogous conditions. In both reactors, the reaction mechanism was similar: there was a zero-order dependency in oxygen and a first-order dependency in ethanol. The different reaction orders indicate that oxygen and ethanol interact with different surface sites, possibly ethanol with gold and oxygen with the support. The study showed that the catalytic performance improves in flow by about 30% for conversion and by 10% for acetic acid selectivity. The enhancement is associated mainly with the greater resistance of gold to sintering in the flow reactor. The study underlines the necessity of switching research to flow systems in order to benchmark more efficiently and identify potential catalysts for industrial implementation as well as to enhance our understanding of triphasic reactions.ISSN:2058-988

Implantálható kardioverter-defibrillátor által sikeresen megszüntetett malignus kamrai ritmuszavar dystrophia myotonicában szenvedő betegben = Successful termination of ventricular arrhythmias with implantable cardioverter defibrillator in a patient with myotonic dystrophy

Összefoglaló. A dystrophia myotonica (DM) multiszisztémás, autoszomális domináns módon öröklődő, többségében felnőttkori izombetegség, melynek incidenciája 1 : 8000. A betegség kapcsán fellépő izomszöveti degeneráció a harántcsíkolt izomszövet átépülése mellett a szívizomszövetet is érinti, ami fontos oki szerepet játszik az érintett betegek csökkent várható élettartamában. A DM-ben szenvedők halálozásának közel egyharmadáért a cardiovascularis okok tehetők felelőssé. Esetriportunkban egy 52 éves, korábban kritikus bradycardia és I. fokú atrioventricularis blokk miatt pacemakerimplantáción átesett, DM-mel diagnosztizált nőbeteg kardiológiai utánkövetését mutatjuk be. A hirtelen szívhalál rizikóstratifikációja céljából elvégzett invazív elektrofiziológiai vizsgálat során kamrafibrilláció lépett fel, így a korábban implantált pacemakerelektródák mellé sokkelektróda került beültetésre, a pacemakerkészüléket implantálható kardioverter-defibrillátorra (ICD) cseréltük. Az 1 éves ICD-kontrollvizsgálat során azt találtuk, hogy a beültetés óta 22, tartós kamrai tachycardiával járó epizód lépett fel, melyek közül a készülék valamennyit sikeresen terminálta. Az eset bemutatásával szeretnénk rámutatni arra, hogy a magas cardiovascularis rizikócsoportba tartozó DM-betegek azonosítása kiemelkedő fontosságú lehet a hirtelen szívhalál megelőzése érdekében. Orv Hetil. 2021; 162(46): 1856-1858. Summary. Myotonic dystrophy (DM) is one of the most frequent adulthood diseases of the skeletal muscles, which develops multisystemic features and shows autosomal dominant trait. In DM, tissue degeneration affects not only the skeletal, but the cardiac muscle, too. In one third of the patients, the cause of death is of cardiac origin. We report on our patient's case, who was diagnosed with DM at the age of 52, in whom episodes of critical bradycardia with first-degree atrioventricular block was detected, resulting in a pacemaker implantation. Invasive cardiac electrophysiological study was performed, during which ventricular fibrillation was registered. A shock electrode was added to the previously implanted pacemaker, enabling defibrillation in case of detection of a sustained ventricular arrhythmia. During the 1-year follow-up, 22 episodes of sustained ventricular tachycardia were identified, with the device successfully terminating the malignant arrhythmias. Our case shows that electrophysiological study and the succeeding implantation of an implantable cardiac defibrillator is highly important in identifying and terminating ventricular arrhythmias in high-risk DM patients. Orv Hetil. 2021; 162(46): 1856-1858