Gyöngyi Székely

Babeş-Bolyai University, Klausenburg, Cluj, Romania

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Publications (13)19.22 Total impact

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    ABSTRACT: The occurrence and importance of photoautotrophic picoplankton (PPP, cells with a diameter <2 μm) was studied along a trophic and salinity gradient in hypersaline lakes of the Transylvanian Basin (Romania). The studied lakes were found to be rich in PPP, with abundances (maximum 7.6 × 106 cells mL−1) higher than in freshwater and marine environments of similar trophic conditions. The contribution of PPP to the total phytoplankton biovolume did not decrease with increasing trophic state as it was generally found in other aquatic environments. Regardless of the trophic conditions, the contribution of PPP could reach 90–100 % in these hypersaline lakes. We hypothesized that the PPP predominance might be the result of the low grazing pressure, since heterotrophic nanoflagellates (the main grazers of PPP) were absent in the studied samples. There were significant differences in community composition among the lakes along the salinity gradient. CyPPP predominated in less saline waters (mainly below 5 %), while EuPPP were present along the entire salinity range (up to 18.7 %), dominating the phytoplankton between 3 and 13 % salinity. Above 13 % salinity, the phytoplankton was composed mainly of Dunaliella species.
    No preview · Article · Nov 2014 · Extremophiles
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    ABSTRACT: Introduction: Cystic fibrosis is a progressive multisystemic disease which affects the quality of life of patients. Aim: The aim of the study was to evaluate quality of life in Hungarian patients with cystic fibrosis. Methods: Validated Hungarian translation of The Cystic Fibrosis Questionnaire - Revised was used to measure quality of life. Clinical severity was determined on the basis of Shwachman-Kulczycki score. Lung function was measured using spirometry. Results: 59 patients were included from five centres in Hungary. The relationships between 8-13 year-old children self-report and parent proxy report was 0.77 (p<0.001) in physical functioning, 0.07 (p<0.001) in emotional functioning, 0.51 (p<0.001) in eating, 0.21 (p<0.001) in treatment burden, 0.54 (p<0.001) in body image, 0.49 (p<0.001) in respiratory symptoms and 0.40 (p<0.001) in digestive symptoms domains. Conclusions: In contrast to physical domains weak correlations were observed between answers obtained from children and their parents in psychosocial domains. The perception of both patients and their parents should be assessed when measuring quality of life in paediatric patients with cystic fibrosis. Orv. Hetil., 2013, 154, 784-791.
    Full-text · Article · May 2013 · Orvosi Hetilap
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    ABSTRACT: Our survey has revealed that the phytoplankton in the anthropo-hypersaline lakes of the Transylvanian Basin (Romania) was often dominated by photoautotrophic picoplankton (PPP, cells with a diameter <2 μm). Therefore, the aim of this study was to identify PPP members both in the summer and the winter communities using molecular biological techniques, denaturing gradient gel electrophoresis (DGGE) and sequence analysis. The applied PCR-DGGE methods were highly specific to cyanobacteria and green algae. A total of 11 different plankton taxa were identified that were related to several distant taxonomic groups. PPP were represented by a simple community and consisted of two major genotypes, one from the green algal species Picochlorum oklahomense and the other related to marine Synechococcus isolates (Cyanobacteria). These marine PPP species were recorded for the first time in inland saline lakes from Europe. Besides picoplankton, several additional marine taxa (e.g. cryptophytes and haptophytes) were detected among the nanoplankton species. The presence of the identified marine and hypersaline species could be explained by wind, precipitation or waterfowl transfer; however, this latter could have smaller importance.
    Full-text · Article · Aug 2012 · Extremophiles
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    ABSTRACT: Human enterovirus 109 (EV109) is a recently identified recombinant enterovirus in family Picornaviridae from acute paediatric respiratory illness in Nicaragua. EV109 have not been reported elsewhere. Our aims were the molecular detection and genetic analysis of EV109 from acute childhood respiratory infections in Hungary. Nasopharyngeal aspirates were collected from children under age of 10 years with acute respiratory infections treated in Department of Pulmonology, Kaposi Mór Teaching Hospital, Mosdós, Hungary. Samples were taken from 15 October to 15 May in two respiratory seasons 2005/2006 and 2006/2007. Samples were tested using EV109 specific VP1 primers by RT-PCR method. One (1.1%) of the 92 nasopharyngeal aspirates was positive for EV109 collected from a 2.5-year-old child in January, 2007. The main symptoms were dropping nose, fever (38.1°C), hard cough and wheezing associated with bronchitis and pneumonia. Based upon the VP1 gene region EV109 (L87/HUN/2007, JN900470) has 93% nucleotide identity and identical recombinant pattern to the prototype EV109. This is the first detection of the novel recombinant enterovirus, EV109, in Hungary (in Europe). This study supports the possibility that EV109 is able to cause acute respiratory infections, in addition, it might be plays a part in lower respiratory disease with hospitalization in children.
    No preview · Article · Jun 2012 · Acta Microbiologica et Immunologica Hungarica

  • No preview · Article · Sep 2011 · Current Opinion in Biotechnology
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    ABSTRACT: Torque teno midi virus/small anellovirus (TTMDV/SAV) is a member of the family Anelloviridae. It has a single-stranded, circular, negative-sense DNA genome. Its pathogenic role in human disease remains to be confirmed. In this study, viral shedding, molecular epidemiology and genetic diversity of TTMDV/SAV were studied in human body fluids. Nasopharyngeal aspirates collected from children with acute respiratory disease were tested by PCR/nested PCR for TTMDV/SAV in two seasons (2005/2006, 2006/2007). Two years later, additional urine, stool, and serum samples and nasopharyngeal aspirates were collected from eight symptomless children for follow-up investigation. Forty-three (46.7%) of the 92 nasopharyngeal aspirates collected contained TTMDV/SAV. High genetic diversity was observed; however, identical sequences were also detected in two patients. The mean age of the infected children was 3 years (1 months-8 years), and 58% of them were female. Co-infection with RSV was detected in 23% of the samples. In a follow-up study, nasopharyngeal aspirates and serum of six (75%), stool samples of four (50%) and urine samples of two (25%) of the eight children were anellovirus-positive. None of the anellovirus sequences were identical in the two collection periods, but identical sequences were detected in different body fluids collected at the same time from the same child. TTMDV/SAVs shedding was detected in four human body fluids. As a consequence, it is possible that generalized infection and fecal/uro-oral transmission of TTMDV/SAV occur. TTMDV/SAVs are frequently present in nasopharyngeal aspirates, although the variants may only be transient agents. Further research is needed to investigate the pathogenesis and pathogenic role of TTMDV/SAV.
    No preview · Article · May 2011 · Archives of Virology
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    ABSTRACT: To determine allele distribution and genetic parameters for two populations living in the Romanian region of Transylvania: Hungarians from Cluj and Szeklers from Covasna county, and to compare the results between the two populations and with other Hungarian and Romanian populations. Allele frequencies for 15 autosomal STR loci (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, and FGA), several forensic parameters, and paternity parameters were determined for Szekler Hungarians of Covasna county (CV-Sze, n=278) and non-Szekler Transylvanian Hungarians, who were represented by Hungarians from Cluj county (CJ-Hu, n=146). Average expected heterozygosity was above 70%. The combined power of discrimination and combined power of exclusion values were high. All tested loci were in agreement with Hardy-Weinberg equilibrium, with the exception of the CSF1PO locus for Covasna county. Pairwise population comparison tests and exact population differentiation tests showed no significant differences between the CJ-Hu and CV-Sze populations, and the CV-Sze group showed greater differences from other Romanian populations than did the CJ-Hu group. Hungarians from Cluj show greater genetic heterogeneity than Szeklers from Covasna. The loci tested are suitable for studying micro-differentiation between these two populations, and between these populations and other populations in Hungary and Romania.
    Full-text · Article · Dec 2010 · Croatian Medical Journal
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    ABSTRACT: Stress tolerance of plants relies on molecular processes that occur at the cellular level and are integrated by the complex regulatory network of the multicellular organisms. One of the mostly widespread environmental stress that impairs the metabolism, development and productivity of many crop plants is generated by elevated concentrations of sodium chloride in the soil solution that surrounds the root system. The main objective of the present study is to investigate physiological and biochemical changes induced in leaf cells of different lettuce varieties, in order to identify the sources of differential salt tolerance and to perform a selection of varieties able to survive in the presence of salt stress. The physiological and biochemical markers used by us to reveal different aspects of salt stress tolerance of lettuce varieties were energetic efficiency of photochemical reactions in chloroplasts, changes is chlorophylls and carotenoid pigment content of thylakoid membranes, cell membrane damage due to peroxidation of unsaturated fatty acids in membrane lipids, the rate of carbon dioxide assimilation by mesophyll cells, stomatal conductivity during leaf gas exchange, and free proline content of leaf cells performing osmoregulation. From among the many parameters of the induced chlorophyll fluorescence related to quantum efficiency of photosynthesis, the vitality index or relative fluorescence decay (Rfd) was the most sensitive one. The timeresolved dynamics of stomatal conductance and net carbon dioxide assimilation showed that osmotic stress induced by high salt concentrations is more severe during the first hours after exposure to salt stress, and the velocity and degree of recovery allows a fine selection of the more tolerant lettuce varieties. Membrane damage by lipid peroxidation is enhanced only by high salt concentrations (100 mM) and seems to be proportional with the salt sensitivity of different lettuce cultivars. Free proline content of young leaf cells increases very much under salt stress, and the highest concentrations of this osmolyte can be found in cold-sensitive varieties.
    No preview · Article · Jan 2010 · Annals of the Romanian Society for Cell Biology
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    J Sz · Demeter · Beatrice Kelemen · Gyöngyi Székely · O Popescu
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    ABSTRACT: Since genomic DNA typing projects were started in Romania, five studies representing six populations have been carried out in Transylvania. All these results were cumulated and an updated Transylvanian database (Trs-6) was created. A comparison of the initial and updated Transylvanian databases was made in order to check consequences of the update. The comparison performed between the two databases revealed significant differences at 4 loci. When compared to five other databases (Moldavia, Dobruja, Wallachia, Romania and FBI), significant differences between the original and the updated databases were reported for 10 of the 15 loci analyzed. Therefore, the use of the updated database is recommended any time population data comparison with Transylvanian database has to be done.
    Full-text · Article · Jan 2010 · Annals of the Romanian Society for Cell Biology
  • P. Pankovics · H. Szabó · G. Székely · K. Gyurkovits · G. Reuter

    No preview · Article · Sep 2009 · Journal of Clinical Virology
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    ABSTRACT: Human respiratory syncytial virus (hRSV) is one of the major causes of respiratory infection of infants and children worldwide. The molecular epidemiology of hRSV is unknown in Hungary. Our aims were the molecular detection and genetic analysis of hRSV from childhood respiratory infections in Hungary. Nasopharyngeal aspirates were collected from children under the age of 10 years with acute respiratory infections provided by the Pediatric Department of the Hospital for Chest Diseases in Mosdós. Samples were taken from 15 October to 15 May in seasons of 2005/2006 and 2006/2007. The clinical and epidemiological data were collected prospectively. The amplification of the surface fusion glycoprotein (F) and the attachment glycoprotein (G) genes of viral RNA was made by RT-PCR method. PCR-products were sequenced and analyzed by phylogenetic analysis. Nasopharyngeal aspirates of 104 children were examined out of which 23 (22.1%) samples - 16 males (69.6%) and 7 females (30.4%) - (first season: 1/49, 2%; second season: 22/55, 40%) contained hRSV. The hRSV infections were taking place from December to March. The average age was 2.1 years (1 month to 8 years). The leading symptoms were dropping nose, fever, cough and wheezing. Thirty-nine point one percent of the hRSV infected children had underlying disease. Based upon the F region 22 (96%), viruses genetically belonged to type A and 1 (4%) was classified as type B hRSV. Based upon the G region, out of the 11 type A viruses 8 (72.7%) belonged to group GA5 and 3 (27.3%) to group GA2. Viral nucleotide sequence was identical in several cases. To our knowledge, this is the first report on molecular detection and genetic analysis of the two types (A and B) of hRSV of children under the age of 10 with respiratory infections in Hungary. In winter and spring hRSV is an important cause of childhood respiratory infections, particularly in infants, often requiring hospitalization.
    Full-text · Article · Feb 2009 · Orvosi Hetilap
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    ABSTRACT: Human metapneumovirus was identified in 2001 as a respiratory-tract pathogen that has been classified as a new genera in family Paramyxoviridae. Molecular detection of human metapneumovirus in Hungary. Human metapneumovirus was identified in nasopharyngeal aspirate amplification of the viral fusion and nucleocapsid genes by reverse transcription-polymerase chain reaction followed by sequencing and phylogenetic analysis. A 4 years-old girl with chronic respiratory syndrome chronically treated with anti-asthma drugs was admitted to hospital in November 2005 with acute respiratory syndrome and atelectasis. Nasopharyngeal aspirate was negative for common bacteria by culture and for influenza and coronavirus by reverse transcription-polymerase chain reaction. By contrast, specimen was positive by reverse transcription-polymerase chain reaction and was confirmed by sequencing both genes (nucleocapsid and fusion) of human metapneumovirus. Human metapneumovirus (HUN 05-L20) clustered into the subgroup B1 has the closest nucleotide similarity (98%) to JPS03-194 (AY530094) detected in Japan. Human metapneumovirus contributes as an etiological agent of acute lower and upper respiratory tract infection especially in winter season in children with bronchiolitis, pneumonia or episodes of asthma exacerbation in Hungary, too.
    No preview · Article · Jan 2007 · Orvosi Hetilap
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    Csaba Bartha · Laszlo Fodorpataki · Gyöngyi Székely · Octavian Popescu
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    ABSTRACT: Increased soil salinity is a major environmental stress factor for many plants, and limits crop yields. Lettuce is a frequently grown, moderately salt-sensitive crop plant, with many different cultivars. Their physiological diversity when exposed to salt stress enables breeders to efficiently select those cutivars more suitable to grow under conditions of salt stress associated with drought and global warming. The aim of this work is to study the physiological diversity of frequently cultivated lettuce varieties subjected to salinity stress, enabling an efficient selection of more tolerant cultivars. Different functional parameters of induced chlorophyll fluorescence, molar ratios between the main photosynthetic light-harvesting pigments, dry biomass accumulation and seed germination dynamics are evaluated in the context of physiological diversity of lettuce cultivars. Potential and effective light use efficiency is generally decreased only by severe salt stress (exposure to 150 mM NaCl for several days), the light reactions of photosynthesis being relatively resistant to dehydration and ion toxicity exerted by elevated salinity. The relative fluorescence decrease, also known as the vitality index of photosystem II, is one of the most suitable physiological markers of salt stress tolerance, making possible a good distinction between resistant, tolerant and sensitive lettuce cultivars. Germination energy is also a good functional indicator of differential salt sensitivity of lettuce cultivars. As a general compensatory mechanism of growth regulation and as a consequence of water deficit, dry biomass production is moderately increased by short-term mild salinity (50 mM NaCl). While the total chlorophyll content of lettuce leaves is decreased by salt stress, the molar ratio between chlorophylls a and b exhibits a moderate but statistically significant increase, because of a more pronounced disturbance of chlorophyll-b homeostasis. Determination of the evaluated physiological parameters is simple and cost-effective, being a good tool for screening lettuce varieties for efficient cultivation on soils with increasing salt content. Possible cross-tolerance for cold stress and salt stress is also discussed. Introduction Salt stress is a serious limiting factor for the development of terrestrial plants, as more than 800 million ha of land throughout the world are affected by salt. A significant proportion of recently cultivated agricultural land has become saline owing to land clearance or irrigation, both of which cause water tables to rise and concentrate salts in the root zone. Of the current 230 million ha of irrigated land, 45 million ha (20%) are salt-affected. Irrigated land accounts for only 15% of the total cultivated area, but because it has at least twice the productivity of rain-fed land, it produces approximately one third of the world's food supply [3, 15, 40]. Lettuce, an increasingly important component of a healthy diet, is a good source of vitamins, other antioxidants, essential mineral ions and several secondary metabolites such as flavonoids and other phenolic compounds. At present there are several promising attempts for using lettuce cultivars as eco-toxicological test organisms, as biomarkers of pollution, as well as an important source of health-promoting phytochemicals [2, 21, 23, 24, 25, 27, 35]. Lettuce is considered to be a moderately salt-sensitive crop, with a threshold electrical conductivity of 1.3 dS m -1 , but a wide range of salt tolerance can be identified among its different cultivars: e.g. the 'Romaine' or 'Cos' lettuce cultivars (Lactuca sativa var. longifolia) are considered far more tolerant of salinity than the 'Iceberg' cultivars (Lactuca sativa var. capitata) [10, 18, 28, 30].
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Publication Stats

49 Citations
19.22 Total Impact Points


  • 2010-2014
    • Babeş-Bolyai University
      • • Faculty of Biology and Geology
      • • Department of Biology and Ecology in Hungarian
      Klausenburg, Cluj, Romania
  • 2011-2013
    • Kaposi Mór Oktató Kórház
      Toponár, Somogy, Hungary