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  • Author or Editor: L. Nagy x
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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 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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Frozen fillets of Atlantic herrings (Clupea harengus) were used to evaluate the effect of glaze with or without addition of selected herbal extracts on lipid oxidation and sensory properties during 8 months of freezing storage under −14 °C. Fillets were divided into four groups: control non-glazed group, glazed group without addition of herbal extracts, and glazed groups with addition of hawthorn (Crataegus oxyacantha L.) extract (0.3%) and agrimony (Agrimonia eupatoria L.) extract (0.3%). The antioxidant activity and total phenolic content in hawthorn and agrimony extracts, and their effect on lipid deterioration expressed as thiobarbituric acid reactive substances were measured. The results showed that the herbal extracts of hawthorn and agrimony are effective antioxidants and good sources of total phenols. Significant influence of herbal extracts added into glaze on the extent of lipid oxidation changes has been obvious within 4 months storage of herring fillets under freezing conditions. Finally, positive influence of glaze and herbal extracts on organoleptic characteristics of fish fillets was found.

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Acta Alimentaria
Authors: N. Adányi, L. Szalóki-Dorkó, R. Tömösközi-Farkas, A. Nagy and É. Kónya
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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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Acta Alimentaria
Authors: I. Rurik, E. Gyömörei, L. Biró, K. Nagy, A. Regöly-Mérei and M. Antal

The aim of this study was to evaluate the nutritional status of elderly belonging to one primary care office. Twenty-seven men and 26 women, all over 60 years, were involved. Nutritional assessment, anthropometric measurements were performed, serum proteins, lipid and iron status and haematological parameters were determined. Energy and protein intake was sufficient, but the distribution of energy with a high fat and low carbohydrate was inadequate. Iron, copper, calcium, retinol and folate intake was lower, whereas sodium, ascorbic acid and cobalamin intake was higher than the Hungarian recommendation. The prevalence of obesity characterized by body mass index or waist circumference was higher in women than in men. The percentage of pathological levels of lipid parameters was also higher in women. No iron deficient erythropoesis was detected, but high serum ferritin concentration as a marker of body iron store was determined in some cases.  General practitioners have possibilities to influence the nutritional habits of elderly, thereby reducing the incidence of obesity, cardiovascular diseases and stroke. Iron status of Hungarian elderly looks to be satisfactory, so supplementation without testing the iron status would be useless and harmful.

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