Authors:E. Nagy, I. Éliás, L. Körmendy, and J. Czeglédi-Jankó
Development of rapid methods is often needed for the in-line process control of the proximate composition (e.g. fat or moisture content) of meat in the meat processing plants. This paper reports on the continuous wave nuclear magnetic resonance (CW-NMR) technique applied for determining fat content in fresh meat. The interfering moisture content in meat was removed by microwave drying and the dried residue was transferred quantitatively into the NMR-tubes. The total analysis time was about 35 min. Experiments were performed with pork (with a fat content from 1.7% to 21%), beef (with a fat content from 1.0% to 16.1%), lard (rendered pork fat) and tallow (rendered beef fat) samples and with their combinations: lard-tallow, lard-lean pork, tallow-lean beef and lard-tallow-lean beef-lean pork. The regression (prediction) equations (NMR-signal vs. fat content determined with the Soxhlet reference method) of pork and beef did not differ significantly. However, there was a noticeable difference between the regression lines of pure lard and pure tallow. Moreover, the latter ones differed from the regression equations of pork, beef and of the various meat-fat combinations. The variability of the fatty acid composition of the fat also seems to influence the stability of the calibration curves, because the sensitivity of the CW-NMR signal to the fatty acid composition interferes with the quantitative determination of fat content in meat.
Authors:E. Kiss, L. Palkovics, E. Szathmáry, and G. Nagy
A destructive seed-borne pathogen, formerly described as Pleospora papaveracea affects opium poppy (Papaver somniferum L.) plants, grown in Hungary, causing considerable qualitative and quantitative losses. The symptoms of the disease were frequently observed in the field between 1999 and 2006. Seventeen Hungarian isolates were obtained from poppy and cultures were established on malt extract agar from naturally infected seeds, diseased foliage, pods and stem. The pathogens proved to be Crivellia papaveracea and a distinct taxon, Brachycladium papaveris based on morphological characterization of conidia, conidiophores and cultures, moreover molecular investigation of the ITS region. Significant morphological differences were observed among the isolates originating from distinct plant parts, however, cultural characteristics were similar. Molecular studies revealed that morphological and cultural differences or similarities do not correspond with taxonomic position of the isolates. Morphological variation of the isolates mainly depended on their origin and might be explained with the differences of microclimatic conditions.
Authors:S. Szalai, I. Kósa, T. Nagy, and L. Szarka
Water and pollution transport takes places in fissures, and fissures may also reduce the stability of the rock body. Therefore, fissures in rock are an important issue, especially in case of multi-directional fissure systems, where the situation is more complicated.The so-called azimuthal technique, by using the Schlumberger array is a routinely applied method in geoelectric fissure detections. As we demonstrate it by using analogue model measurements, this method has several shortages. In absence of
information, the fissure directions could be obtained only in 60% of the total cases with a precision of ±10%. We have also demonstrated that the effectivity of the method becomes even worse, when the covering sediment layer is thicker. At the same time, when we simply rejected the anisotropy paradox, it was found, that the effectivity of the method is increasing with increasing sediment thickness. The original azimuthal technique is based on the generally accepted hypothesis of the so-called geoelectric anisotropy paradox. The analogue modelling results have made clear that the critical point of the method is the application of the anisotropy paradox. The fissure directions can only be determined, if the conditions of the anisotropy paradox are clearly defined. However, having more than one fissure directions, statistically these fissure directions can be correctly determined.
Authors:I. Gresits, S. Tölgyesi, L. Nagy, and J. Solymosi
A radioisotope-excited energy-dispersive X-ray fluorescence system has been constructed and used for the analysis of blood samples for trace elements. The possibility of determination of trace elements in blood by X-ray fluorescence based on comparison with standard reference materials has been outlined and the applicability of the method demonstrated by the analysis of blood samples. The method enables fast, non-destructive direct analyses to be carried out without lengthy sample pretreatment on a routine basis.
The analysis was conducted on the national database of the station tests carried out between May 1996 and February 2001, using the Hungarian Large White (LW) and Hungarian Landrace (LR) breeds, and the A-line of the Ka-Hyb hybrid (MLW). Days of test, total amount of feed consumed and valuable cuts were taken into the analysis to test the random distribution of the animals' phenotypic measurements and predicted breeding values across the contemporary groups of origin. The phenotypic measurements of all traits were clearly positively associated with the herds of origin (b = 0.52-1.08). Animals with favourable phenotypic measurements originated from better herds. On the contrary, the predicted breeding values seemed to be independent of the herd effects (b= -0.16-0.08) and suggested a possible random distribution across the contemporary groups.
Authors:K. Gajda-Schrantz, L. Nagy, E. Kuzmann, and A. Vértes
Eight di-n-butyltin(IV) complexes with glycolic, 2-hydroxy-propionic, succinic and malic acids, have been prepared by two
different procedures. The compounds were characterised by elemental analysis, FTIR, Raman and119Sn Mössbauer spectroscopy. The IR and Raman data indicated the presence of bidentate and/or monodentate carboxylate groups,
non linear C−Sn−C bonds, and Sn−O bonds within the complexes. The results of Mössbauer spectroscopic measurements, based on
point-charge model calculations, have shown the occurrence of trigonal bipyramidal environment in the central tin(IV) atom,
besides the octahedral and tetrahedral structure.
Authors:Gy. Vankó, L. Bottyán, D. Nagy, E. Szilágyi, and A. Vértes
Nuclear inelastic resonant scattering of synchrotron radiation was applied to the study solutions of 57Fe complexes. In order to reveal different inelastic contributions solutions of two different 57Fe complexes of different molecular dimensions with solvents of substantially different viscosities were studied. We argue that the only former experiment available in the literature overestimates the role of the diffusivity in affecting the spectrum. The first direct observation of an intramolecular vibrational transition assisting the nuclear resonance absorption in a liquid is reported.
Authors:L. Kredics, Zsuzsanna Antal, Ilona Dóczi, L. Manczinger, F. Kevei, and Elisabeth Nagy
Cefditoren is the active form of cefditoren pivoxil, a new, broad-spectrum oral cephalosporin with strong in vitro activity against penicillin-susceptible and resistant Streptococcus pneumoniae. In this study, the minimum inhibitory concentrations (MICs) of cefditoren were determined for a special selection of S. pneumoniae isolates known to be susceptible, moderately susceptible or fully resistant to penicillin; these isolates originated from the lower respiratory tract of adults with pneumonia or the upper respiratory tract of children with or without symptoms of infection. Some of this latter group of isolates exhibited extremely high MICs to penicillin (³32 mg/l), whereas the MICs of cefditoren did not exceed 2 mg/l. The MIC50 and MIC90 of cefditoren proved to be 0.25 and 1.0 mg/l, respectively, with a range of MICs £0.015-2.0 mg/l for all the tested S. pneumoniae isolates. Its good activity suggests that cefditoren is expected to be a potent drug in infections caused by penicillin-resistant and multidrug-resistant S. pneumoniae.
Authors:L. Kredics, Zsuzsanna Antal, A. Szekeres, L. Manczinger, Ilona Dóczi, F. Kevei, and Elisabeth Nagy
Species belonging to the filamentous fungal genus Trichoderma are well known as potential candidates for the biological control of plant pathogenic fungi and as cellulase producers of biotechnological importance. Several data were published in the last decade also about the clinical importance of this genus, indicating that Trichoderma strains may be potential opportunistic pathogens in immunocompromised patients. However, there is a lack of information about the potential virulence factors of clinical Trichoderma strains. This study was designed to examine the extracellular proteolytic enzymes of six clinical T. longibrachiatum isolates. Supernatants from induced liquid cultures of the examined strains were screened for proteolytic enzyme activities with 11 different chromogenic p-nitroaniline substrates. The production of trypsin-like, chymotrypsin-like and chymoelastase-like protease activities cleaving N-Benzoyl-L-Phe-L-Val-L-Arg-p-nitroanilide, N-Succinyl-L-Ala-L-Ala-L-Pro-L-Phe-p-nitroanilide,and N-Succinyl-L- Ala-L-Ala-L-Pro-L-Leu-p-nitroanilide, respectively, was common among the strains examined. Separation of trypsin- and chymotrypsin-like activities by column chromatography revealed, that both systems are complex consisting of several isoenzymes. The pH-dependence of these two protease systems was also studied. Based on the results, the different isoenzymes seem to have different optimal pH values. Extracellular proteolytic enzymes may be involved in the pathogenecity of Trichoderma strains as facultative human pathogens.
Authors:L. Nagy, A. Szorcsik, H. Jankovics, T. Yamaguchi, K. Yoshida, M. Scopelliti, L. Pellerito, and E. Sletten
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.