25 research outputs found

    Plant Growth-Promoting Rhizobacteria : Biotechnological Tools to Improve Cereal Yields

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    Ensuring food security for the world’s growing population is a significant challenge for scientists. Efforts are constantly being made to solve this problem, including the use of expensive molecular engineering techniques, which are not always successful. A cost-effective and environmentally friendly biotechnological alternative would be the use of plant growthpromoting rhizobacteria, demonstrated by numerous studies to play many beneficial roles in improving plant traits, e.g. enhanced yields

    Picophytoplankton predominance in hypersaline lakes (Transylvanian Basin, Romania)

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    The occurrence and importance of photoautotrophic picoplankton (PPP, cells with a diameter <2ÎŒm) was studied a long 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 x 106 cells mL - ) higher than in freshwater and marine environments of similar trophic conditions. The contribution of PPP to the total phytoplankton bio volume did not decrease with in creasing 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 a long 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% salin ity . Above 13% salinity, the phytoplankton was composed mainly of Dunaliella species

    A fitoplankton molekulåris diverzitåsa az Erdélyi-medence sós tavaiban

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    Az ErdĂ©lyi-medence sĂłs tavaira jellemzƑ a magas trofitĂĄs Ă©s az erƑs emberi zavarĂĄs. Ezekben a tavakban pikocianobaktĂ©riumok Ă©s pikoeukariota algĂĄk egyarĂĄnt elƑfordulnak jelentƑs rĂ©szesedĂ©ssel az össz alga biomasszĂĄbĂłl magas trofitĂĄs mellett is. MikroszkĂłpos mĂłdszerek alkamazĂĄsĂĄval megĂĄllapĂ­tĂĄsra kerĂŒlt hogy a nanophytoplanktont a sĂłs tavakban közönsĂ©ges Dunaliella fajok dominĂĄljĂĄk. A fitoplankton mikrszokĂłpos vizsgĂĄlatĂĄnak ĂșjszerƱ eredmĂ©nyei indokoltĂĄ tettĂ©k a fitoplanktont alkotĂł fajok azonosĂ­tĂĄsĂĄt melynek legalkalmasabb mĂłdja a molekulĂĄris biolĂłgiai mĂłdszerek alkalmazĂĄsa. VizsgĂĄlataink sorĂĄn PCR, denaturĂĄlĂł gradiens gĂ©l elektroforĂ©zis Ă©s szekvenciaelemzĂ©s alkalmazĂĄsĂĄval megĂĄllapĂ­tottuk, hogy a fitoplanktont eddig kontinentĂĄlis vizekben nem ismer tengeri cianobakĂ©riumok Ă©s tengeri eukariota algĂĄk alkotjĂĄk. A pikofitoplnaktont tengeri Synechococcus (Cyanobacteria) Ă©s tengeri illetve sĂłs tavi Picochlorum (Chlorophyta) fajok alkotjĂĄk. A tengeri pikofitoplankton mellett több tengeri nanoplanktonfaj (Guillardia sp., Isochrysis sp.) is azonosĂ­tĂĄsra kerĂŒlt. Ezekben a kontinentĂĄlis sĂłs tavakban azonosĂ­tott tengeri algafajok jelenlĂ©tĂ©re magyarĂĄzat lehet a szĂ©l- Ă©s a vĂ­zimadarak ĂĄltali terjesztĂ©s, esetleg a sĂłrĂ©tegekbƑl kioldodĂł algasejtek, azonban ennek a kiderĂ­tĂ©sĂ©re tovĂĄbbi vizsgalatok szĂŒksĂ©gesek

    Az ozmotikus stresszvålasz szabålyozåsa magasabbrendƱ növényekben. = Regulation of osmotic stress responses in higher plants

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    PĂĄlyĂĄzatunkban egy Ășj genetikai rendszert dolgoztunk ki, amely alkalmas a stressz jelĂĄtvitelben szerepet jĂĄtszĂł növĂ©nyi gĂ©nek azonosĂ­tĂĄsĂĄra. RT-PCR mĂłdszerrel jellemeztĂŒk több stressz indukĂĄlt Arabidopsis gĂ©n aktivitĂĄsĂĄt kĂŒlönbözƑ stressz Ă©s homonkezelĂ©s utĂĄn. A gĂ©nek 5? promoter rĂ©giĂłjĂĄt megklĂłnoztuk, Ă©s promoter nĂ©lkĂŒli luciferĂĄz (LUC) illetve zöld fluorescens protein (GFP) riporter gĂ©nekhez kapcsoltuk. A riporter gĂ©nek aktivitĂĄsĂĄt transzgenikus Arabidopsis növĂ©nyekben tanulmĂĄnyoztuk. Az Ășj szabĂĄlyozĂł faktorok azonosĂ­tĂĄsa Ă©rdekĂ©ben egy Arabidopsis cDNS könyvtĂĄrat hoztunk lĂ©tre a pER8-GW expressziĂłs vektorban, ami ösztradiol ĂĄltal indukĂĄlhatĂł expressziĂłs kazettĂĄt hordoz. A cDNS könyvtĂĄr segĂ­tsĂ©gĂ©vel egy transzgenikus Arabidopsis növĂ©ny populĂĄciĂłt hoztunk lĂ©tre. A transzgenikus növĂ©nyeket sĂł rezisztenciĂĄra, ABA Ă©rzĂ©kenysĂ©gre illetve a mĂĄr korĂĄbban beĂ©pĂ­tett riporter gĂ©n aktivitĂĄsĂĄnak megvĂĄltozĂĄsĂĄra teszteltĂŒk. Több olyan Arabidopsis vonalat sikerĂŒlt azonosĂ­tani, amelyekben az ösztradiol adĂĄsa megnövekedett sĂł vagy ABA toleranciĂĄval, illetve a riporter gĂ©n aktivitĂĄsĂĄval jĂĄrt egyĂŒtt. A C38-33 vonalban megemelkedett sĂł toleranciĂĄt kaptunk a beĂ©pĂŒlt cDNS transzkripciĂłjĂĄnak aktivĂĄlĂĄsĂĄval. A cDNS egy Ășj, S1 domĂ©n-t tartalmazĂł fehĂ©rjĂ©t kĂłdol. Az ADH-121 vonalban egy AP tĂ­pusĂș transzkripciĂł faktort azonosĂ­tottunk, ami kĂ©pes volt az ADH-LUC riporter gĂ©n kontrukciĂł aktivĂĄlĂĄsĂĄra a kĂŒlsƑ környezeti tĂ©nyezƑktƑl fĂŒggetlenĂŒl. | We have developed a genetic system to identify new regulatory factors, controlling stress responses in higher plants, namely in Arabidopsis. Using quantitative RT-PCR, we have characterized the expression of several stress-responsive genes in different conditions and hormonal treatments. The 5? promoter sequences of 5 stress-induced genes have been cloned and fused to promoterless reporter genes, such as the firefly luciferase (LUC) or the green fluorescence protein (GFP). Activity of the reporter gene constructs was characterized in transgenic Arabidopsis plants, using non-destructive assays. In order to identify new regulatory factors, a transformation-competent cDNA library was created in the plant expression vector pER8-GW, carrying an estradiol-responsive expression cassette. Large-scale Arabidopsis transformation generated a collection of transgenic plants, each carrying a cDNA clone. Transgenic plants were screened for salt tolerance, ABA insensitivity or activation of reporter gene constructs. Several salt tolerant or ABA insensitive lines were obtained and characterized. In some lines reporter genes were activated upon the induction of transgene expression, in the absence of stress. In the line C38-33 increased salt tolerance was obtained by the activation of a full length cDNA, coding for a previously unknown protein with S1 domain. In the line ADH-121, activation of an AP transcription factor lead to the increased expression of the ADH-LUC reporter construct

    CystĂĄs fibrosisban szenvedƑ betegek Ă©letminƑsĂ©gĂ©nek felmĂ©rĂ©se MagyarorszĂĄgon

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    BevezetĂ©s: A cystĂĄs fibrosis progresszĂ­v genetikai betegsĂ©g, amely korlĂĄtozhatja a betegek mindennapi Ă©letĂ©t, befolyĂĄsolja Ă©letminƑsĂ©gĂŒket. CĂ©lkitƱzĂ©s: A szerzƑk cĂ©lul tƱztĂ©k ki a hazai cystĂĄs fibrosisban szenvedƑ betegek Ă©letminƑsĂ©gĂ©nek felmĂ©rĂ©sĂ©t. MĂłdszer: Az Ă©letminƑsĂ©g Ă©rtĂ©kelĂ©sĂ©re betegsĂ©gspecifikus kĂ©rdƑív (The Cystic Fibrosis Questionnaire – Revised) magyar nyelvre validĂĄlt vĂĄltozatĂĄt alkalmaztĂĄk. A betegsĂ©g sĂșlyossĂĄgi ĂĄllapotĂĄt Shwachman–Kulczycki-pontszĂĄm segĂ­tsĂ©gĂ©vel hatĂĄroztĂĄk meg. Spirometriai vizsgĂĄlat is törtĂ©nt. EredmĂ©nyek: A vizsgĂĄlatban 59 beteg (ĂĄtlagĂ©letkor 14,03±4,8 Ă©v) vett rĂ©szt öt magyarorszĂĄgi centrumbĂłl. A 8–13 Ă©ves korosztĂĄlyban a gyermekek Ă©s szĂŒleik vĂĄlaszai között a következƑ korrelĂĄciĂłkat ĂĄllapĂ­tottĂĄk meg: fizikai aktivitĂĄs = 0,77 (p<0,001); Ă©rzelmi ĂĄllapot = 0,07 (p<0,001); Ă©tkezĂ©si zavarok = 0,51 (p<0,001); kezelĂ©s terhe = 0,21 (p<0,001); testkĂ©p = 0,54 (p<0,001); lĂ©gĂști tĂŒnetek = 0,49 (p<0,001); emĂ©sztĂ©si tĂŒnetek = 0,40 (p<0,001). KövetkeztetĂ©sek: A gyermekkori Ă©letminƑsĂ©g felmĂ©rĂ©se sorĂĄn a gyermekek Ă©s szĂŒleik vĂ©lemĂ©nye szorosan megegyezett azokban a dimenziĂłkban, amelyek a fizikĂĄlis terĂŒletre vonatkoztak, azonban a pszichoszociĂĄlis domĂ©nekben lĂ©nyeges kĂŒlönbsĂ©gek voltak mĂ©rhetƑk. CystĂĄs fibrosisos gyermekek Ă©letminƑsĂ©g-vizsgĂĄlata sorĂĄn mind a gyermekek, mind a szĂŒlƑk vĂ©lemĂ©nyĂ©nek figyelembevĂ©tele ajĂĄnlott. Orv. Hetil., 2013, 154, 784–791. | 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

    Interactions and Chemical Transformations of Coronene Inside and Outside Carbon Nanotubes

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    By exposing flat and curved carbon surfaces to coronene, a variety of van der Waals hybrid heterostructures were prepared, including coronene encapsulated in carbon nanotubes, and coronene and dicoronylene adsorbed on nanotubes or graphite via π – π interactions. The structure of the final product is determined by the temperature of the experiment and the curvature of the carbon surface. While at temperatures below and close to the sublimation point of coronene, nanotubes with suitable diameters are filled with single coronene molecules, at higher temperatures additional dimerization and oligomerization of coronene occurs on the surface of carbon nanotubes. The fact that dicoronylene and possible higher oligomers are formed at lower temperatures than expected for vapor-phase polymerization indicates the active role of the carbon surface used primarily as template. Removal of adsorbed species from the nanotube surface is of utmost importance for reliable characterization of encapsulated molecules: it is demonstrated that the green fluorescence attributed previously to encapsulated coronene is instead caused by dicoronylene adsorbed on the surface which can be solubilized and removed using surfactants. After removing most of the adsorbed layer, a combination of Raman spectroscopy and transmission electron microscopy was employed to follow the transformation dynamics of coronene molecules inside nanotubes
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