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Abstract  

Complexes of adenosine and related compounds (adenosine-5’-monophosphate, adenosine-5’-triphosphate and pyridoxal-5-phosphate) with Bu2SnO and/or BuSnCl2 were prepared in the solid state. The compositions of the complexes were determined by standard analytical methods. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1. The FT-IR spectra demonstrated that Bu2SnO reacts with the D-ribose moiety of the ligands, while Bu2SnCl2 is coordinated to the deprotonated phosphate group. The basic part of the ligands does not participate directly in complex formation. Comparison of the experimental Mössbauer Δ (quadrupole splitting) values with those calculated on the basis of the pqs concept revealed that the organotin(IV) moiety has Tbp and in some cases also Th geometry. The adenosine complex contains the organotin(IV) cation in two different surroundings (Tbp and Th). The local structures of the complexes were determined by means of EXAFS measurements. At the same time a number of organotin(IV) complexes containing different organo moieties of calf thymus DNA were also prepared. Similarly as above, EXAFS data were obtained for these compounds and analyzed by using multishell models up to 300 pm. These results are the first structural data (bond lengths) on complexes formed with organotin(IV)-DNA and related compounds.

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Abstract  

57Co Mössbauer emission spectra of undoped and Fe or Mg melt-doped LiNbO3 single crystals show substantial amounts of the nucleogenic Fe3+ charge state (*Fe3+) which was generated as an after-effect of the electron-capture of 57Co2+. The proportion of *Fe3+ is markedly dependent on the Mg content and on the stoichiometry of the sample. Electron trapping is described within the model of competing acceptors. The capabilities of the model are investigated in defect structure analysis and charge trapping studies of LiNbO3.

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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 PotatoVirus 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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Acta Botanica Hungarica
Authors: V. Kerényi-Nagy, L. Bakay, M. Valachovič, V. Feráková, and I. Hodálová

The article deals with the distribution of three species from the genus Rosa in Slovakia. Field research, sampling and herbarium sheet revision at the Herbarium of Department of Botany, Faculty of Natural Sciences Comenius University (SLO) and the Herbarium of Institute of Botany, Slovak Academy of Sciences (SAV) showed new data on the distribution of Rosa pocsii Kerényi-Nagy, Rosa polyacantha (Borbás) H. Br. and Rosa zagrabiensis Vuk. et H. Br. in Slovakia. Detailed taxonomic description, distribution of selected taxa in Slovakia, a determination key and a comparative table of the sect. Rubiginosae are given.

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Studies involving morphological description with both dominant (RAPD) and codominant (SSR, isoenzyme) molecular markers were made on 28 maize inbred lines of known genetic background with a final aim of prediction of heterosis. The genetic distance and degree of relationship between the lines was determined using cluster analysis. Only a very limited extent of allele polymorphism could be detected in isoenzyme analyses as the 28 lines formed only 16 gel electrophoretic groups, indicating that certain lines had identical isoenzyme patterns. On the basis of RAPD and gene-specific microsatellite (SSR) markers, however, all the lines could be distinguished from each other. When the lines were grouped according to genetic background it was found that although the individual marker systems only partially reflected the actual relationships between the lines, a joint processing of the data, supplemented with morphological data, revealed a close correlation between the groups formed on the dendrogram and the genetic background.

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Studia Slavica
Authors: János L. Nagy, Mihály Káprály, Mária Tétényi, István Fried, and Zsuzsanna Kalafatics

Nyelv, stílus, irodalom. Köszönto könyv Péter Mihály 70. születésnapjára. Budapest 1998, 646 p. (????, ?. ?.); - ?????? ?., ??????? ????? ??? ?????? ??????????? ????????? ?. ????????? ????????? ????????????? ???????? ?????? ???????????.(Studia Ukrainica et Rusinica Nyíregyháziensia 12). ?????????? 2002, 238 p. ( ???????, ?.); - ?. ?. ??????? ? ?. ?. ???????, ????????? ? ?. ?. ?????????. The Tolstoys' Correspo ndence with N. N. Strakhov. (?? ??????? ???????????????? ????? ?. ?. ????????). A. A. Donskov (Ed.). Compiled by L. D. Gromova & T. G. Nikiforova. (Tolstoy Series 3). Slavic Research Group at the University of Ottawa and State L. N. Tolstoy Museum, Moscow, 2000, 308 p. (??????, ?.); - Marija Mitrovic, Geschichte der slowenischen Literatur. Von den Anfängen bis zur Gegenwart. Klagenfurt-Ljubljana-Wien 2001. 617 p. (Fried, I.); - ??????? ??????? ??????????? ??????????? ???????? I. ?????? 2001, 213 p. (?????????, ?.)

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Acta Microbiologica et Immunologica Hungarica
Authors: T. Emri, Brigitta Oláh, L. Sámi, Zs. Molnár, Márta Nagy, Tünde Pusztahelyi, and I. Pócsi
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The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-mediated hypersensitivity to fungal allergens could not be proven in our patients.

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