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Ultrastructural characteristics of muscle fibers and neuromuscular contacts were investigated during two stages of embryogenesis of the pulmonate snail Lymnaea stagnalis. The first muscle cells appear as early as during metamorphosis (50–55% of embryonic development), whereas previously, in the trochophore/veliger stages (25–45%), muscular elements cannot be detected at all. The first muscle fibers contain large amounts of free numbers, a well-developed rER system and only a few irregularly arranged contractile elements. The nucleus is densely packed with heterochromatine material. At 75% adult-like postmetamorphic stage, the frequency of muscle fibers increases significantly, but, bundles of muscle fibers cannot yet be observed. Furthermore the muscle cells are characterized by large numbers of free ribosomes and numerous rER elements. Fine axon bundles and single axon processes, both accompanied by glial elements, can already be found at this time. Axon varicosities with different vesicle and/or granule contents form membrane contacts with muscle fibers, but without revealing membrane specialization on the pre- or postsynaptic side. The late development of the muscle system and neuromuscular contacts during Lymnaea embryogenesis correlates well with the maturation of different forms of behavior of adult, free-living life, and also with the peripheral appearance of chemically identified components of the embryonic nervous system of central origin.

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The physiognomy and the species composition of the Salici cinereae-Sphagnetum recurvi (Zólyomi 1931) Soó 1954 are variable in Hungary. This association has been divided into two new subassociations by the authors, due to the slight differences in their moss layer. As a representation they compared 27 phytocoenological relevés, made by 4 different botanists in 10 different mires, by multivariate analysis. Those peat moss dominated willow carrs, in which the dominant moss species are Sphagnum squarrosum and/or Sphagnum fimbriatum subsp. fimbriatum, are called Salici cinereae-Sphagnetum recurvi sphagnetosum squarrosi subass. nov., on the contrary those, in which any species of the Sphagnum recurvum agg. (S. fallax, S. angustifolium, S. flexuosum) and/or Sphagnum palustre are dominant, are called Salici cinereae-Sphagnetum recurvi sphagnetosum recurvi subass. nov. The two submitted subassociations of peat moss dominated grey willow carr are very similar. They could be found together or independently, on a terrestrial or on a floating mire. All of them are a part of the successional series of mire development, which can result a continental raised bog under recent climate, too.

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Liver transplantation (LT) is the sole treatment modality of most of diffuse liver diseases. Simultaneous-pancreas-kidney (SPK) transplantation is also a life saving operation for IDDM patients. Both procedures are established treatment options in the European Community (EC) and in the US. These procedures are performed in a significantly smaller number in Hungary. Having a larger demand for LT than the supply of cadaver donors alternative solutions are sought to increase the number of transplantable livers. In Hungary partly the shortage of donors and the shortage of recipients are the factors rendering the number of LTs and SPKs low. These factors can be changed by better organisation and good survival data that make the two procedures accepted by the community of physicians.

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Prematurity has got special challenge for clinicians and also other medical staff, such as microbiologists. Immature host defense mechanisms support early-onset sepsis, which can be very serious with very high mortality. While the past decade has been marked by a significant decline in early-onset group B streptococcal (GBS) sepsis in both term and preterm neonates, the overall incidence of early-onset sepsis has not decreased in many centers, and several studies have found an increase in sepsis due to gram-negative organisms. With increasing survival of these more fastidious preterm infants, late-onset sepsis or specially nosocomial bloodstream infection (BSI) will continue to be a challenging complication that affects other morbidities, length of hospitalization, cost of care, and mortality rates. Especially the very low birthweight (VLBW) infants sensitive to serious systemic infection during their initial hospital stay. Sepsis caused by multiresistant organisms and Candida spp. are also increasing in incidence, has become the most common cause of death among preterm infants. This review focuses on the clinical microbiology of neonatal sepsis, particularly among preterm babies, summarizing the most frequent bacterial and fungal organisms causing perinatally acquired and also nosocomial sepsis.

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Abstract  

Iron(III) complexes of D-saccharose and D-glucose were prepared. The compositions of the complexes were determined by standard analytical methods. The Mössbauer spectra reflected the presence of high-spin iron(III) in the polynuclear species. EPR spectroscopy demonstrated antiferromagnetically coupled iron(III) centers within the solid complexes. The13C NMR spectra indicated the presence of a mixture of coordination isomers of iron(III) complexes containing the sugar ligand in differently bound forms.

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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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Streptococcus pneumoniae is an important pathogen with significant morbidity and mortality rates worldwide, especially among children <5 years. Healthy carriers are the most important sources of pneumococcal infections, and the nasopharyngeal colonisation is the most prevalent among children attending communities such as day-care centres (DCCs). The conjugate pneumococcal vaccines (PCVs) were shown to have an impact on the colonisation, and so play an important role in inhibiting infections. In this study we compared the nasal carriage of healthy children attending DCCs in Szeged, Hungary in 2003/2004, when nobody was vaccinated, and in 2010, when already 1/5 of the children received PCV-7. Significant differences were observed in the serotype distribution, representing a marked shift from the previously widespread vaccine-types (mostly 6A or 14) to others (11A and 23F). The new serotypes showed higher antibiotic susceptibility. The bacterium exchange between children was clear from the pulsed-field gel electrophoresis (PFGE) patterns, and the circulation of certain international clones plays also a role in these dynamic changes.

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Abstract  

A number of complexes of ligands containing {O,N,S} donor atoms (2,3,4,6-tetra-O-acetyl-b-D-thioglucopyranoside, 1-thio-b-D-glucose, 2-aminomercaptopurine, 4-amino-2-mercaptopyrimidine and 2-amino-6-mercaptopurine-9-D-riboside) with di-n-butyltin(IV) oxide, diphenyltin(IV) oxide, tribenzyltin(IV) chloride, and trimethyltin(IV) chloride were prepared in the solid state. It was found that the complexes contain the organotin(IV) moiety and the ligand in a ratio of 1:1 or 2:1. The FTIR and Raman spectra clearly demonstrated that the organotin(IV) moieties react with the {S} atom of the ligands, while di-n-butyltin(IV) oxide is coordinated to the deprotonated hydroxy group. In several cases, the basic part of the ligands also participates in complex formation. Comparison of the experimental Mössbauer D values with those calculated on the basis of the pqs concept revealed that the organotin(IV) moiety has trigonal-bipyramidal geometry, and in certain cases tetrahedral geometry too. Some of the complexes contain the organotin(IV) cation in two different surroundings.

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