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Abstract  

A number of 15 [Fe(Diox#x00B7;H)2L2] type chelates and [Fe(Diox)3(BOR)2] clathrochelates (Diox#x00B7;H2 — dimethylglyoxime, glyoxime, propoxime, nyoxime, furyl-dioxime; L-pyridine, alkyl-pyridine derivatives, diethyl-phenyl-phosphine, diethyl-p-tolyl-phosphine) were obtained and characterized by means of far and middle FTIR and Mössbauer spectroscopic methods. Some structural problems were discussed on the basis of the optical data.The DSC measurements show the higher thermal stability of the clathrochelates without O—HO intramolecular hydrogen bonds (with asymmetric octahedral structure), as compared to the [Fe(Diox#x00B7;H)2L2] trans, symmetric chelates containing O—HO bonds. The kinetic parameters of the thermal decomposition of the complexes have been derived using the nomogram method.

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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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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 non-destructive activation analytical method developed for the determination of the axial concentration distributions of Al, Si and K residual additives in sintered tungsten rods is briefly described. A 14 MeV neutron generator is used to produce the reactions27Al(n, p)27Mg,28Si(n, p)28Al and39K(n, 2n)38K and the activities are compared with standards. A weighted least-squares fitting program is used for peak area determination of the scintillation spectra. A scheme of the irradiating and measuring arrangement with a pneumatic sample-transfer system is presented. The system is applicable to large-scale routine analysis and lends itself well to automation. The results of preliminary measurements with this arrangement are given.

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Abstract  

The effect of Xe+ irradiation and that of subsequent annealings on Fe/Sn bilayer have been studied by119Sn conversion electron Mössbauer spectroscopy. It seems that the effectiveness of ion-beam mixing is comparable to the thermal treatment of the bilayer.

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Abstract  

Dibenzyltin(IV) complexes of carbohydrate derivatives were prepared and studied by Mössbauer and FTIR spectroscopy and by thermogravimetry. The Mössbauer studies indicated that the reaction between dibenzyltin(IV)-dichloride and sugar-type ligands led to reaction products containing tin(IV)-oxide. beside the dibenzyltin(IV) sugar complex. These two type of species were shown to be in weak interaction. Comparison of the experimental quadrupole splitting values with those calculated on the basis of the partial quadrupole splitting concept revealed the steric arrangements of the coordination sphere of tin(IV) in the sugar complexes.

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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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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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Acta Alimentaria
Authors: L. Biró, B. Rabin, A. Regöly-Mérei, K. Nagy, B. Pintér, E. Beretvás, E. Morava and M. Antal

The lack of data regarding dietary and lifestyle habits of Hungarian university students prompted us to undertake a cross-sectional pilot study of students of Semmelweis University, Budapest. A total of 264 students (78 males with mean age of 21.4±2.6 y and 186 females with a mean age of 21.2±2.6 y) were involved in the study. The questionnaires contained inquiries of energy and nutrient intake, use of vitamin and mineral supplements, food frequency, meal frequency and physical activity. Statistical analysis was carried out using SPSS for Windows 9.0. The energy, protein and fat intake was somewhat higher than the Hungarian Recommended Dietary Allowances (HRDA) (BIRÓ & LINDNER, 1999). Sodium intake was alarmingly high. Vitamin D consumption was inadequate. The intake of the members of vitamin B group with exception of B12 and niacin was insufficient. The daily consumption of milk, dairy products, fruits and vegetables was deficient. The meal pattern was unbalanced. Only 66% of males and 52% of females were involved in a regular physical activity. Our results suggest that nutrition should be introduced into the medical curriculum as a separate and full-fledged course of study.

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Acta Alimentaria
Authors: M. Antal, A. Regöly-Mérei, L. Biró, K. Nagy, J. Fülöp, E. Beretvás, E. Gyömörei, O. Kis and A. Vámos

This study investigates the nutritional status, life-style practices, serum vitamin D and bone density of adolescents. A total of 326 adolescents, aged between 11 and 14 years, were involved in the present examination: after winter 110 boys and 97 girls (March 2002 and February 2003), and after summer 66 boys and 53 girls (October 2002 and 2003) were investigated. Energy and nutrient intake and life-style practices were assessed. Body mass and height were measured, body mass index was calculated. Serum concentration of 25-hydroxyvitamin D [25(OH)D] was determined. Bone mineral density of calcaneus was measured. Protein intake was higher than the Hungarian RDA. All of the students had vitamin D intake far below the RDA, 33.3% of boys and 43.2% of girls had Ca intake below 70% of RDA, and sodium intake was more than twice higher than the RDA. After winter, 2% of boys and 8% of girls were considered vitamin D deficient and 11% and 19% vitamin D insufficient, respectively. After summer, 24% of boys and 21% of girls had 25(OH)D level over the reference range. The mineral content of bone was insufficient in 12.9% of boys and 10.4% of girls, respectively. The majority of the students had physical activity only in school, incorporated in the timetable.

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