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Abstract

Background

Real-time three-dimensional transesophageal echocardiography (RT 3D TEE) is a novel method providing high spatial and temporal resolution imaging of the heart. During pulmonary vein isolation procedures visualization of the atria, interatrial septum and the ablation catheter is of high importance to increase safety. RT 3D TEE might be a useful tool to guide left atrial ablations.

Case report

A 53-year-old man was referred to our hospital to undergo pulmonary vein isolation procedure for the treatment of symptomatic drug-refractory paroxysmal atrial fibrillation. The transseptal puncture was performed under RT 3D TEE-guidance with direct visualization of the interatrial septum and fossa ovalis. RT 3D TEE provided a three-dimensional view of the puncture with “tenting”-sign and the transseptal needle-fossa ovalis angle enhancing the manipulation of the ablation catheter within the left atrium. The ablation catheter was visualized and tracked during the procedure. No adverse events occurred during the procedure.

Conclusion

Our case report demonstrates the feasibility of RT 3D TEE-guided atrial fibrillation ablation procedures. Safety profile might be improved by the real-time direct view of fossa ovalis. Decrease in fluoroscopy time can be achieved by visualizing the ablation catheter during the procedure.

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Acta Biologica Hungarica
Authors: B. Morgun, A. Richter, D. Deshmukh, V. Stepanyuk, Katalin Kálai, G. Nagy, L. Hufnagel, and Noémi Lukács

Expression of antibodies or antibody fragments in plants is a useful tool for producing active antibody derivatives for diagnostic or pharmaceutical purposes as well as for immunomodulation. We investigated the effect of cellular expression site on the stability and yield of double-stranded RNA (dsRNA)-specific single-chain Fv-fragments (scFv) in transgenic tobacco. Two antibodies (J2 and P6) belonging to the V23(J558) heavy chain variable gene family but differing in the light chain variable domain were used. scFvs were targeted to the cytoplasm - with or without anchoring them in the plasma membrane -, into the endoplasmic reticulum (ER) and to the apoplast. Although high mRNA concentrations were detected in all cases, scFv proteins accumulated only when scFvs were made ER-resident by appropriate signal sequences. When the ER retention signal was removed to allow scFv-secretion to the apoplast, no scFv-proteins were detected. Despite the strong homology of the VH-sequences of J2 and P6 antibodies, only P6 provided a stable scFv scaffold for intracytoplasmic expression. J2-scFv could not be stabilised either by adding a C-terminal stabilisation signal or by anchoring the protein on the cytoplasmic side of the plasma membrane (PM). It was found that dsRNA-specific J2-scFvs are active in vivo and enhance Potato Virus Y induced symptoms in infected tobacco. This is the first report describing the expression and biological effect of RNA-specific antibodies in plants.

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Abstract  

Nine complexes of adenosine and related compounds (adenosine-5'-monophosphate, adenosine-5'-triphosphate, 1-methyl-adenosine, pyridoxal-5-phosphate and -nicotinamide-adenine-dinucleotide-phosphoric acid) with di-n-butyltin(IV) oxide and/or di-n-butytin(IV) dichloride were prepared in the solid state. The compositions of the complexes were determined by standard analytical methods. It was found that the complexes contain organotin(IV) moiety and the ligand in a ratio of 1:1 or 2:1. The FTIR spectra demonstrated that di-n-butyltin(IV) oxide reacts with the D-ribose moiety of the ligands, while di-n-butyltin(IV) dichloride is co-ordinated to the deprotonated phosphate group. The basic part of the ligands does not participate directly in complex formation. Comparison of the experimental Mössbauer QS values with those calculated on the basis of the PQS concept revealed that the organotin(IV) moiety has trigonal-bipyramidal, octahedral and in some cases tetrahedral geometry also. Some of the complexes contain the organotin(IV) cation in two different surroundings.

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Abstract  

Fourteen complexes of di-n-butyltin(IV)2+ cations with flavonoid glycosides (rutin, hesperidin, 2′,4′,3-trihydroxy-5′,4-dimetoxychalkone 4-rutinoside) and flavonoid aglycones (quercetin, morin, hesperitin and sorte flavones) were prepared. The composition of the complexes was determined by standard analytical methods. The results showed that complexes containing diorganotin(IV)2+ moiety and the ligand in 1∶1, 2∶1 or 3∶1 ratio are formed. The FTIR spectra were consistent with the presence of Sn-O (phenol or carbohydrate) vibration in the compounds. The structure of the complexes was measured by Mössbauer spectroscopy. Comparison of the experimental quadrupole splitting with those calculated on the basis of partial quadrupole splitting concept revealed that the complexes are of four types: with the central tin atoms surrounded by donor atoms in a purely trigonal-bipyramidal, octahedral+trigonal-bipyramidal, trigonal-bipyramidal+tetrahedral and octahedral+tetrahedral arrangement. This procedure also distinguished between the different structural isomers of both trigonal-bipyramidal and octahedral complexes. Conclusions could therefore be drawn on the factors determining which of the isomers are formed in the systems. The Mössbauer parameters obtained for organotin(IV)-flavonoid complexes were compared with those measured for organotin(IV)-carbohydrate complexes.

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Orvosi Hetilap
Authors: Márton Magyar, Viktória Zsiros, Anna L. Kiss, Zoltán Zsolt Nagy, and Zsuzsanna Szepessy

Absztrakt:

Bevezetés: A caveolák a plazmamembrán palack alakú, nem klatrinasszociált, 50–100 nanométer nagyságú befűződései, melyeknek legfontosabb integráns membránfehérjéje a caveolin-1. A caveolák kiemelt szerepet töltenek be a sejtek működésében – a vesicularis transzportban, a sejtciklus szabályozásában –, és platformként szolgálnak klasszikus és alternatív jelátviteli folyamatokhoz. Célkitűzés: Vizsgálataink célja a caveolák morfológiai és a caveolin-1 fehérje immunhisztokémiai kimutatása és összehasonlítása fiatal, kontroll (myop, hypermetrop) és szürke hályogos humán szemlencse elülső lencsetokjának epithelialis sejtjeiben. Így arra a kérdésre kerestünk választ, hogy a caveoláknak lehet-e szerepük a szürkehályog-kialakulás folyamatában. Módszer: A nagy myop és hypermetrop (kontroll-), valamint idős, elszürkült lencsével rendelkező betegek refraktív célból végzett műtétje során nyert elülső lencsetokokat mint szövetmintákat vizsgáltuk. Mindkét vizsgálati csoportban az elülső lencsetokok ultravékony metszeteit transzmissziós elektronmikroszkópiával tanulmányoztuk, valamint a szövetminták félvékony metszetein immunhisztokémiai jelölést végeztünk polyclonalis caveolin-1- és cavin-1-ellenes antitestekkel. Eredmények: Az immunhisztokémiai eredmények alapján a kontrollcsoportban a lencseepithelsejtekben jelentős caveolin-1-jel mellett alacsony cavin-1-jelet mértünk. A szürke hályogos mintákban azonban erőteljes cavin-1-expresszió és a kontroll- (myop) sejtekben tapasztalt mértékű caveolin-1-szignál volt megfigyelhető. Az elektronmikroszkópos képeken kontrollesetben caveolák gyakorlatilag nem voltak kimutathatók, míg a cataractás metszeteken emelkedett mennyiségű caveolát figyeltünk meg. Következtetés: Mivel a cavin-1 szükséges a caveolin-1 mellé, hogy a caveolák jellegzetes morfológiája kialakuljon, feltételezzük, hogy a cavin-1-expresszió változása tehető felelőssé az elektronmikroszkópos felvételeken megfigyelhető eltérésekért. Ezen eredmények utalhatnak arra, hogy a caveolák szerepet játszhatnak a szürkehályog-képződés folyamatában. Orv Hetil. 2019; 160(8): 300–308.

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Abstract  

A number of dibutyltin(IV) complexes of polyhydroxyalkyl carboxylic acids (O donor atoms) and amino acids (O,N donor atoms) were prepared in the solid state. The binding sites of the ligands were determined by means of FT-IR, Raman and 13C NMR spectroscopy. Partial quadrupole splitting calculations were utilized to determine the coordination geometry around the Sn(IV) centre by means of Mössbauer measurements. The results showed that in the solid state oligomeric complexes are formed, with the -COO- groups as bridges between the organometallic cations. The {Sn} atoms are mostly in trigonal bipyramidal surroundings. The Sn-O and Sn-C bond distances were determined by EXAFS measurements to be 207-234 and 295 pm, respectively. Evaluation of the pH-metric and NMR titration curves in Me2Sn(IV)-D-gluconic acid system revealed that the equilibria in aqueous solution are fairly complicated. In acidic solution, the formation of 1 : 1 and 1 : 2 -COO- coordinated species predominate, but deprotonation of the alcoholic -OH groups also starts at very low pH. In the pH range 5-9, NMR provides experimental evidence of ligand-exchange reactions without pH-metrically detectable proton release. In alkaline solution, further deprotonation processes occur, resulting in either alkoxo or mixed hydroxo complexes. The carboxylate coordination is expected for the amino acid ligands but the shift of the νN-H stretching vibrations in the FT-IR spectra demonstrated that the ammine group also binds to the metal ion in the solid Bu2Sn(IV)complexes.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: A. Vértes, K. Süvegh, E. Kuzmann, K. Burger, L. Nagy, K. Schrantz, and N. Buzas

Abstract  

The discovery of radioactivity started the nuclear research. The nuclear techniques are very powerful tools in structural chemistry, as well. We would like to support this statement by two examples in this paper. We present a series of Mössbauer measurements which give information about the coordination structure of some dibutyltin (IV) complexes of carbohydrate derivates. The other example will demonstrate how the positron lifetime spectra can reflect the temperature dependence of water structure.

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Acta Microbiologica et Immunologica Hungarica
Authors: Zsuzsanna Antal, L. Kredics, J. Pakarinen, Ilona Dóczi, Maria Andersson, Mirja Salkinoja-Salonen, L. Manczinger, A. Szekeres, L. Hatvani, C. Vágvölgyi, and Elisabeth Nagy

Potential virulence factors of 9 saprophytic and 12 clinical Trichoderma longibrachiatum strains were examined in the present study, in order to compare their capacity to cause infection in humans. All of the strains were able to grow at temperatures up to 40 °C and at pH values ranging from 2.0 to 9.0. Carbon and nitrogen source utilization experiments revealed that all of the strains were able to utilize a series of basic amino acids both as sole carbon and nitrogen sources. The MIC values of the tested antifungal drugs were found to be 0.016-8 µg/ml for amphotericin B, 64-256 µg/ml for fluconazole, 0.5-32 µg/ml for itraconazole and 0.008-1 µg/ml for ketoconazole in the case of the examinedis olates. Metabolites of the strains inhibited the growth of different bacteria, furthermore, compounds produced by three clinical isolates reduced the motility of boar spermatozoa, indicating their toxicity to mammalian cells as well. On the whole, there were no significant differences in the examined features between strains derived from clinical or soil samples. The question, however, whether all environmental Trichoderma longibrachiatum strains have the capacity to cause infections or not, remains still unanswered.

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Nanopages
Authors: A. Szabo, A. Fonseca, L. P. Biro, Z. Konya, I. Kiricsi, A. Volodin, C. Van Hasendonck, and J. B.Nagy

Some recent results on the synthesis of coiled carbon nanotubes (CNTs) are summarized. Several supported catalysts can lead to the formation of coiled CNTs. Interestingly, certain domains of the coil pitch and coil diameter are favoured, and two “stability islands”are found in the 3D representation of the number of coiled CNTs as a function of both coil pitch and coil diameter. It is emphasized that these nanotubes are formed either by introducing pairs of five-membered ring - seven-membered ring or by forming haeckelite structures. The coiled CNTs could be used in nanocomposite reinforcement as well as special sensors based on their remarkable mechanical and electrical properties.

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Acta Microbiologica et Immunologica Hungarica
Authors: B. Kádár, M. Szász, Katalin Kristóf, Natasa Pesti, G. Krizsán, Julianna Szentandrássy, L. Rókusz, K. Nagy, and Dóra Szabó

The aim of the study was to investigate the biofilm-production of 60 Pseudomonas aeruginosa strains isolated from clinical samples and to examine the effect of different antimicrobials and their combinations with clarithromycin on biofilm-formation.The minimal inhibitory concentrations (MICs), minimal biofilm inhibitory concentrations (MBICs), and antibiotic synergy by calculating the fractional inhibitory concentration (FIC) index were determined for the following antibiotics: ceftazidime, cefepime, piperacillin/tazobactam, imipenem, meropenem, levofloxacin, ciprofloxacin, gentamicin, amikacin, tobramycin, netilmicin and clarithromycin.A total of 14 (23.3%) isolates out of 60 isolates of P. aeruginosa were biofilm positive. Cefepime, imipenem and meropenem had the lowest MIC90 values. Piperacillin/tazobactam and clarithromycin had the highest MIC90 values. Imipenem, meropenem, piperacillin/tazobactam and clarithromycin had the lowest MBIC90 values.For biofilm-forming P. aeruginosa strains 2-fold to 128-fold higher MBIC values than MIC values were obtained for ceftazidime, cefepime, imipenem, amikacin and netilmicin. The MBIC was 2-fold to 512-fold lower then the MIC values in the case of piperacillin/tazobactam, ciprofloxacin, levofloxacin and clarithromycin.Synergy was generally demonstrated for clarithromycin in combination with aminoglycosides, fluoroquinolones or ceftazidime. However, surprisingly it was found that combinations of clarithromycin with carbapenems or cefepime led to an antagonistic interaction: combination of clarithromycin with imipenem, meropenem or ertapenem showed antagonism in 37.5%, 50% and 62.5% of the strains tested whereas its combination with cefepime expressed antagonism in 75% of the strains, respectively. To the best of our knowledge no one has previously described this phenomenon so far.

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