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Nine genotypes of melon (Cucumis melo L.) were selected for the investigation of regeneration. Most of the tested varieties showed regeneration ability on medium containing 0.5 mg l−1 or 1 mg l−1 BA, but following the appearance of shoot buds, only six varieties produced leafy shoots. The effect of combinations of BA with different auxins (IAA, NA, 2,4-D) and ABA in the culture medium on shoot regeneration was tested on cotyledon explants of ‘Hógolyó’ and ‘Hale’s Best’. To establish optimal conditions for the adventitious shoot induction six types of seedling-derived explants were prepared from seedlings of four different ages. The best results for shoot forming capacity were achieved with cotyledons followed by decapitated seedlings and hypocotyls derived from 4-day-old seedlings. Cotyledon segments of ‘Hógolyó’ and ‘Hale’s Best’ were also cultivated on media with different concentrations of IAA and BA supplemented with 0.26 mg l−1 ABA. The highest number of well-formed plantlets was counted for ‘Hógolyó’ on the medium supplemented with 0.9 mg l−1 BA+ 0.6 mg l−1 IAA+ 0.26 mg l−1 ABA. This is the first report on the in vitro regeneration of ‘Hógolyó’ from decapitated seedling and hypocotyl explants and of ‘JavÍtott Zentai’, ‘Muskotály’, ‘Hógolyó’, ‘Tétényi csereshéjú’ and ‘Magyar Kincs’ from cotyledon explants.

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Stress tolerance is associated with the activation of antioxidant compounds and enzyme systems that are capable of neutralising the reactive oxygen species (ROS) continually produced in response to stress. The present experiment was designed to compare the heat tolerance of four winter wheat varieties in the shooting and grain-filling stages by investigating changes detected in antioxidant enzyme activity and yield components in response to heat stress.Heat treatment was found to cause a significant rise in the activity of the glutathione-S-transferase and catalase enzymes, while there was usually a less intense decline in the activity of guaiacol peroxidase.An analysis of yield data revealed that heat stress had a more pronounced effect during grain filling in this experiment than at the beginning of shooting, as shown by the greater reduction in thousand-kernel weight and yield.

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Barley-infecting isolates of WDV were collected in the field of near Sofia. The complete genomes of two isolates were amplified by PCR, cloned into pGEM-T plasmid and sequenced. The two clones were the same size and showed complete homology. The WDV-Bg17 clone was compared with Barley dwarf virus, Oat dwarf virus and Wheat dwarf virus isolates. Based on DNA sequences WDV-Bg17 isolate shows high homology (95–97%) to Barley dwarf virus isolates and differs from Oat dwarf virus (71% homology) and Wheat dwarf virus (85% homology).

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Myocardial infarction is responsible for the majority of cardiovascular mortality and the pathogenesis of myocardial damage during and after the infarction involves reactive oxygen species. Serious efforts are under way to modulate the developing ischemia/reperfusion injury and recently the use of hydrogen sulfide (H2S) emerged as a new possibility. H2S has been best known for decades as a pungent toxic gas in contaminated environmental atmosphere, but it has now been recognized as a novel gasotransmitter in the central nervous and cardiovascular systems, similarly to nitric oxide (NO) and carbon monoxide (CO). This finding prompted the investigation of the potential of H2S as a cardioprotective agent and various in vitro and in vivo results demonstrate that H2S may be of value in cytoprotection during the evolution of myocardial infarction. Although several questions remain to be elucidated about the properties of this new gasotransmitter, increased H2S levels may have therapeutic potential in clinical settings in which ischemia/reperfusion injury is encountered. This review article overviews the current understanding of the effects of this exciting molecule in the setting of myocardial ischemia/reperfusion.

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Abstract  

Aerosol samples collected around the Chilean site Lonquimay during major volcanic activities in January 1989 have been subjected to microPIXE measurements of 1 mm lateral resolution in the Debrecen Institute. Elemental concentrations relative to calcium have been determined for Al, Si, P, S, K, Sc, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, and Ba in 187 individual aerosol particles with the particle sizes between 15 mm and 1 mm. On the basis of a cluster analysis performed on the data set we defined eight clusters. Scatter plots for selected pairs of elements as Si/Al, K/Si, S/Cl, and Al/S elemental ratios that are considered as signatures characterizing types and mechanisms in volcanic eruption - have been compared with published data available in the literature for various volcanic sites.

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Acta Veterinaria Hungarica
Authors: Andrea Bistyák, S. Kecskeméti, R. Glávits, I. Tischler, S. Nagy, G. Kardos, and I. Kiss

An epizootic of Pacheco’s disease is reported from a zoo bird population. The infection was introduced by wild-captured Patagonian conures ( Cyanoliseus patagonus ) despite 61 days of quarantine. The disease affected several parrot species and, interestingly, three out of seven bearded barbets ( Lybius dubius ). The mortality rate was 30.93%. Autopsy revealed abdominal hyperaemia with liver haemorrhages and, in less rapid cases, yellowish discoloration and fragility of the liver. Death was caused by the collapse of circulation. Histopathology demonstrated liver cell necrosis, disintegration of the lobular structure, and a few intranuclear inclusion bodies. Icosahedral virions were detected by electron microscopy. The virus was isolated in the allantoic cavity of embryonated chicken eggs as well as in chicken embryo fibroblast cell culture. A 281-bp-long fragment of psittacid herpesvirus DNA was detected by PCR in cell culture material and liver samples of the affected birds. To our knowledge this is the first report of Pacheco’s disease in bearded barbets as well as the first occurrence of Pacheco’s disease in Hungary.

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Acta Alimentaria
Authors: L. Bujdosó, F. Budán, T. Varjas, L. Szabó, A. Csejtei, J. Iványi, A. Huszár, I. Arany, I. Kiss, and I. Ember

Peripheral blood stem cells (PBSC) could contribute to tissue regeneration through the ability to form somatic cells. CD34 positivity is regarded as stem cell (SC) or endothelial progenitor cell (EP) marker. According to literature natural substances could increase the release of CD34 positive (CD34+) cells. In this study we investigated the basic rate of CD34+ cells in peripheral blood of CBA/Ca (H-2k haplotype) and BALB/c inbred mice by flow cytometry. Then we treated the mice with a new mixture of medical herbs, and we measured the level of CD34+ cells at 1, 3, 6, 18 and 24 hours after the treatment. A biological rhythm in the untreated blood was detected. Moreover the used herbal compounds increased the number of CD34+ cells.Although SC number is individually and highly variable in peripheral blood, the fluctuation could be used as a biomarker like the other compounds of peripheral blood in different aspects in risk assessment.

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Abstract  

It is demonstrated that combined PIXE and PIGE measurements are suitable for the accurate determination of the elemental concentration of glass samples. Borosilicate glasses used as high voltage insulators in Van de Graaff accelerators and tested for the relevant physical properties have been analyzed. A correlation between concentrations and physical properties has been found, supporting the additivity rule.

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Abstract

In recent years, post mortem multi-slice computed tomography (MSCT) is increasingly applied for forensic and pathologic examination. However, classical dissection remains dominant in everyday practice. Lack of quantifiable data on the coronary system has become a disadvantageous attribute of traditional autopsy. Therefore, post mortem MSCT angiography was performed in 80 ex corpo hearts with the aim of improving the accuracy and quantitative documentation of pathologic and forensic diagnoses of coronary artery disease (CAD). Hearts were perfused by introducing a new oily or synthetic resin, or using both contrast materials successively. Then the perfused organs were processed for imaging. Detailed angiographic analysis enabled us to localize, map and quantify coronary calcifications, stenoses, and to characterize the types of atherosclerotic plaques. Significant early or late complications of widely used percutaneous coronary interventions (PCI) and coronary bypass surgery (CABS) could be revealed using CT analysis. Furthermore, by using our oily contrast material and CT imaging, we could identify and visualize the clinically important small caliber nodal arteries (diameter 0.4–2.0 mm). The present work suggests that post mortem CT angiography and post-processing of the data may improve the quality of pathologic and forensic diagnosis. Our collection of coronary casts including digital data are available for further analysis.

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The quasispecies nature of three animal pathogenic RNA viruses of field origin was examined by testing variants of classical swine fever virus (CSFV) originating from geographically different areas, feline coronavirus (FCoV) detected from the same animal by successive sampling, and rabbit haemorrhagic disease virus (RHDV) originating from successive outbreaks in the same geographic area. Clinical samples were investigated using reverse transcriptase polymerase chain reaction (RT-PCR) and ensuing single strand conformational polymorphism (SSCP) assay. By the combination of these methods even subtle differences could be detected among the amplified fragments of the same virus species of different origin. FCoV proved to comprise the most and CSFV the less heterogeneous virus quasispecies. The results show that the combination of RT-PCR and SSCP provides novel and highly sensitive means for the characterisation of RNA viruses, with special regard to genome composition, evolution, features of pathogenicity and molecular epizootiology.

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