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Generation of induced pluripotent stem cells by using a mammalian artificial chromosome expression system
No full textDirect reprogramming of mouse fibroblasts into induced pluripotent stem cells (iPS) was achieved recently by overexpression of four transcription factors encoded by retroviral vectors. Most of the virus vectors, however, may cause insertional mutagenesis in the host genome and may also induce tumor formation. Therefore, it is very important to discover novel and safer, non-viral reprogramming methods. Here we describe the reprogramming of somatic cells into iPS cells by a novel protein-based technique. Engineered Oct4, Sox2 and Klf4 transcription factors carrying an N-terminal Flag-tag and a C-terminal polyarginine tail were synthesized by a recently described mammalian artificial chromosome expression system (ACEs). This system is suitable for the high-level production of recombinant proteins in mammalian tissue culture cells. Recombinant proteins produced in this system contain all the post-translational modifications essential for the stability and the authentic function of the proteins. The engineered Oct4, Sox2 and Klf4 proteins efficiently induced the reprogramming of mouse embryonic fibroblasts by means of protein transduction. This novel method allows for the generation of iPS cells, which may be suitable for therapeutic applications in the future
Whole genome sequence of a goose haemorrhagic polyomavirus detected in Hungary
No full textGoose haemorrhagic polyomavirus (GHPV) provoke haemorrhagic nephritis and enteritis of domestic geese. Outbreaks were detected in European countries and caused economic losses for goose keepers. Domestic ducks may be infected with GHPV without any signs typical for geese. The genomic organisation of some isolates was described but the gene functions and the pathomechanisms of the virus was not precisely defined. Here we describe the genome sequence and structure of GHPV of a goose from a Hungarian goose flock showing characteristics of the haemorrhagic nephritis and enteritis. The GHPV genome investigated in this study was 5252 bp long and was very similar (99% nucleotide identity) to sequences deposited in the GenBank. All the whole GHPV genomes possess the same ORFs in length, including the VP1, VP2, VP3, ORF-X, t and T tumour antigens. Amino acid changes are detected mainly in the putative ORF-X region. Data about the GHPV genome imply a conserved genomic structure among isolates from different countries. Genomic and epidemiological studies may help vaccine development efforts and identify potential heterologous reservoirs of GHPV
Prokaryotic phylogenetic diversity of Hungarian deep subsurface geothermal well waters
No full textGeothermal wells characterized by thermal waters warmer than 30°C can be found in more than 65% of the area of Hungary. The examined thermal wells located nearby Szarvas are used for heating industrial and agricultural facilities because of their relatively high hydrocarbon content. The aim of this study was to reveal the prokaryotic community structure of the water of SZR18, K87 and SZR21 geothermal wells using molecular cloning methods and Denaturing Gradient Gel Electrophoresis (DGGE). Water samples from the outflow pipes were collected in 2012 and 2013. The phylogenetic distribution of archaeal molecular clones was very similar in each sample, the most abundant groups belonged to the genera Methanosaeta, Methanothermobacter and Thermofilum. In contrast, the distribution of bacterial molecular clones was very diverse. Many of them showed the closest sequence similarities to uncultured clone sequences from similar thermal environments. From the water of the SZR18 well, phylotypes closely related to genera Fictibacillus and Alicyclobacillus (Firmicutes) were only revealed, while the bacterial diversity of the K87 well water was much higher. Here, the members of the phyla Thermodesulfobacteria, Proteobacteria, Nitrospira, Chlorobi, OP1 and OPB7 were also detected besides Firmicutes
Three new rose microspecies from sect. Rubiginosae in Slovakia
No full textThe 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
Leaf anatomical structures in Central European populations of the broad-leaved Festuca taxa
No full textThis work deals with the leaf blade anatomical structures of the broad-leaved fescue taxa, natural populations of temperate forage grasses, collected from various habitats in Central Europe. The following anatomical features were examined and quantitatively characterised: the ribs of leaves, type of the mesophyll, number of the sclerenchyma ribs, quantity of sclerenchyma tissue, presence of the colourless cells, number of bulliform cells, stomatal complexes and presence of papilla number. It was concluded that the anatomical structures and the main leaf blade characteristics of broad-leaved fescues show several differences between the taxa of Schenodorus and Drymanthele subgenus. The populations of the Schenodorus subgenus present heterogeneous mesophyll, with radial parenchyma, and colourless cells. Strong correlations exist between the bulliform cells and the quantity of sclerenchyma and papillae. The populations of Drymanthele subgenus also present heterogeneous mesophyll, but this is not evident for every taxa and populations. The radial parenchyma and the colourless cells are not specific. There is a positive correlation between the bulliform cells and the quantity of sclerenchyma. The comparative leaf anatomical analysis, could contribute to the better understanding of taxonomic and anatomical diversity in this group
Pathogenicity in Plasmopara halstedii (Sunflower downy mildew) races 710, 714 and 704
No full textPathogenicity including virulence and aggressiveness characteristics was studied on three Plasmopara halstedii (the causal agent of downy mildew) isolates of races 710, 714 and 704 using five single zoosporangium isolates per pathogen isolate. Based on the reaction for the P. halstedii isolates to four sunflower hybrids H1 to H4 varying only in their downy mildew resistance genes, there were differences in virulence spectrum in pathogen isolates. Analysis of five single zoosporangium isolates for P. halstedii isolates showed significant variability within pathogen isolate for all aggressiveness criteria. There were no significant differences among pathogen isolates for all aggressiveness criteria. There were significant differences in the morphology of zoosporangia and sporangiophores for pathogen isolates. Genetic relationships were detected between pathogen isolates using 12 EST-derived markers. There was no intra-race genetic variation, but three genetically-identified groups were detected among pathogen isolates
A study on the Chrysomelidae (Coleoptera) from the Golestan province, Northern Iran
No full textThe fauna of Chrysomelidae (Coleoptera) from Golestan province (Northern Iran) is studied in this paper. In total 26 species from 19 genera and 7 subfamilies (Chrysomelinae, Clytrinae, Criocerinae, Cryptocephalinae, Eumolpinae, Galerucinae and Alticinae) were collected and identified
New records of tydeid, phytoseiid and tenuipalpid (Acari: Tydeidae, Phytoseiidae, Tenuipalpidae) mites from Hungary
No full textThe authors give account of 5 new species, viz. Metalorryia armaghensis (Baker 1968), Neoapolorryia kristinae Momen and Lundqvist 1996, Lorryia zaheri (Baker 1968), Neoseiulus californicus (McGregor 1954) and Tenuipalpus pacificus Baker 1945, which have not been recorded so far in the Hungarian fauna
Response of end tidal CO<sub>2</sub> pressure to impulse exercise
No full textThe purpose of the present study was to examine how end tidal CO2 pressure (PETCO2) is controlled in impulse exercise. After pre-exercise at 25 watts for 5 min, impulse exercise for 10 sec with 200 watts followed by post exercise at 25 watts was performed. Ventilation (V̇E) significantly increased until the end of impulse exercise and significantly re-increased after a sudden decrease. Heart rate (HR) significantly increased until the end of impulse exercise and then decreased to the pre-exercise level. PETCO2 remained constant during impulse exercise. PETCO2 significantly increased momentarily after impulse exercise and then significantly decreased to the pre-exercise level. PETCO2 showed oscillation. The average peak frequency of power spectral density in PETCO2 appeared at 0.0078 Hz. Cross correlations were obtained after impulse exercise. The peak cross correlations between V̇E and PETCO2, HR and PETCO2, and V̇E and HR were 0.834 with a time delay of −7 sec, 0.813 with a time delay of 7 sec and 0.701 with a time delay of −15 sec, respectively. We demonstrated that PETCO2 homeodynamics was interactively maintained by PETCO2 itself, CO2 transportation (product of cardiac output and mixed venous CO2 content) into the lungs by heart pumping and CO2 elimination by ventilation, and it oscillates as a result of their interactions