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  • Author or Editor: A. P. Takács x
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The aim of our study was to investigate the susceptibility of some Chenopodium species (Chenopodium album, C. glaucum, C. berlandieri, C. ugandae) to six viruses (Alfalfa mosaic virus, Cucumber mosaic virus, Obuda pepper virus, Potato virus Y, Sowbane mosaic virus, Zucchini yellow mosaic virus). Fourteen plants of each species were mechanically inoculated and virus susceptibility was evaluated on the basis of symptoms and back inoculation. A series of new host-virus relations were determined.

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In this review results are summarized regarding the effect of virus infection on the physiological processes of weeds. Through several host-virus model relations the biomass and seed production, seed viability and germination, nutrient uptake, drought-resistance and photosynthetic pigment content of healthy and virus infected plants were compared. Because of their broad host range and high genetic variability viruses cannot be used for biological weed control. It was concluded that viruses unfavourably can influence physiological processes of weeds. Therefore, they may contribute indirectly to the reduction of competitive ability and population of weeds.

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In the second part of our study we have examined the effect of Tobacco mosaic tobamovirus (TMV) infection on the germination, seed trans­mission, seed viability and seed production of S. nigrum. Transmission of TMV by seeds of S. nigrum was 0.3%. Average seed production of the virus infected plants was reduced by 52%, as compared to the healthy control, and TMV infection also delayed generative development. Virus infection did not influence the germination of the seeds. Viability of seeds derived from ripened (blue-black) berries, was significantly reduced by TMV infection.

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Susceptibility of 33 Lycopersicon species and intra-specific taxa to 6 viruses such as U/246 strain of Cucumber mosaic virus (CMV), Pepino mosaic virus (PepMV), Potato virus X (PVX), NTN strain of Potato virus Y (PVYNTN), Tobacco mosaic virus (TMV) and Tomato mosaic virus (ToMV) were studied. Inoculated plants were tested for susceptibility on the basis of symptoms, serological reactions (DAS-ELISA) and back inoculation. All tested plants were susceptible to PepMV, PVX, TMV and ToMV. However, Lycopersicon esculentum Mill. convar. parvibaccatum Lehm. var. cerasiforme (Dun.) Alef.s.l., L. peruvianum (L.) Mill. and L. hirsutum Humb. et Bonpl. were extreme resistant (immune) to PVYNTN. L. esculentum Mill. convar. infiniens Lehm. var. flammatum Lehm., L. esculentum Mill. convar. fruticosum Lehm. var. speciosum Lehm. and L. esculentum Mill. convar. infiniens Lehm. var. validum Bail. showed extreme resistance to CMV-U/246. The other 30 species and intra-specific taxa were susceptible to CMV-U/246. New compatible and incompatible host-virus relations have been reported. The extreme resistant Lycopersicon intra-specific taxa could be used as resistance sources in tomato breeding.

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Male Wistar rats wearing chronically implanted cortical electrodes were exposed to Mn-containing nanoparticles via the airways for 8 weeks following a 2-week pre-exposure period. The rats’ cortical electrical activity and open field motility was recorded simultaneously, in weekly repetitions. It was supposed that this technique can provide better insight in the development of Mn-induced CNS damage. Decreased motility (less distance covered, longer periods of immobility) and increased total power of cortical electrical activity developed in parallel in the first 4–5 weeks of treatment but showed little change afterwards. Both the behavioral and the electrophysiological effect were in fair correlation with the rats’ internal Mn exposure determined from brain samples. The results confirmed the non-linear dose- and time-dependence of Mn effects suggested by previous studies. Repeated simultaneous behavioral and electrophysiological recording during a longer treatment with neurotoxic metals (or other xenobiotics) seems to be a promising method.

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Authors: P. Fancsovits, Zsuzsa G. Tóthné, Á. Murber, F. Z. Takács, Z. Papp and J. Urbancsek

First polar body (PB) morphology of human oocytes can indicate further embryo development and viability. However, controversial data have been published in this topic. Our retrospective study analyses the fertilization and further development of oocytes in relation to different morphological features of the first PB. The morphology of 3387 MII oocytes from 522 in vitro fertilization (IVF) treatments were assessed before intracytoplasmic sperm injection (ICSI). Oocytes were classified according to their first PB morphology. Assessment of fertilization and embryonic development (cell number, embryo grade, amount of anuclear fragmentation and presence of multinucleated blastomeres) was performed 16-20 and 42-48 hours after ICSI. Our results show that fertilization rate and embryo quality is influenced by PB morphology, while speed of development is not affected by the morphology of the first PB. Contrary to previous findings, our results suggest that oocytes with a fragmented PB had a higher developmental ability than those with an intact PB. However, we observed a lower viability of oocytes with a large PB. Since there are contradictions in this and previous observations, an extensive study is needed with standard hormonal stimulation protocol and oocyte evaluation criteria.

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Authors: A. P. Takács, L. Palkovics, Zs. Basky, G. Kazinczi and Intézet címe Intézet neve

The nucleotide sequence of the coat protein (CP) gene and the 3' non-translated region, in relation to aphid transmission of 7 potato tuber necrotic ringspot isolates of Potato virus Y (PVYNTN) were studied. Five isolates originated from different areas of potato fields in Hungary and two German isolates served as controls. A 5' tail of the nucleotide sequences of the CP region and 3' non-translated region (NTR) were determined. Sequence data were sent to the EMBL GeneBank Database. Homology of nucleotide and amino acid sequences were high among the studied PVY isolates. According to the characteristic regions, all isolates belonged to the PVYNTN strain. All of the tested isolates could be transmitted by the aphid Myzus persicae Sulzer to the test plant Nicotiana tabacum L. verifying the wide distribution of tuber necrotic ringspot strain in Hungary. Our data suggest that the high homology found in the CP region of the different isolates, are suitable for development of coat protein mediated resistance against PVY in commercially important host plants like, e.g. potato.

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Authors: A. Hermanne, F. Szelecsényi, M. Sonck, S. Takács, F. Tárkányi and P. Van den Winkel

Abstract  

Excitation functions were measured by stacked-foil technique for the68Zn(p, 2n)67Ga,68Zn(p,3n)66Ga,natCu(p,xn)62Zn,natZn(p,xn)67Ga,natZn(p,xn)66Ga,natZn(p,px)62Zn andnatZn(p,αx)61Cu nuclear reactions in the energy range from 15–35 MeV. The experimental excitation functions were compared with published data. Our present measurements not only increase the number of available cross section data points for the above reactions, but for some reactions (and in some energy regions) values are presented for the first time.

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Authors: K. Végh, E. Osztoics, P. Csathó, J. Csillag, L. Radimszky, G. Baczó, M. Magyar, T. Takács, A. Lukács and M. Karátsonyi
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Authors: H. Vágó, P. Takács, A. Tóth, L. Gellér, Sz. Szilágyi, L. Molnár, V. Kutyifa, T. Simor and Béla Merkely

Abstract

Cardiac electromechanical resynchronisation therapy (CRT) is an effective non-pharmacological treatment of patients suffering from drug refractory heart failure. However, approximately 20–30% of patients are non-responder. Cardiac magnetic resonance imaging (CMR) may play significant role in clarifying many questions in this patient population. Forty-five patients, suffering from severe drug refractory heart failure, underwent CMR before applying CRT. Left ventricular end-diastolic, end-systolic volumes, ejection fraction, myocardial mass, wall motion disturbances, localisation of non-viable myocardium were determined. Left ventricular dyssynchrony was determined by illustrating wall-time thickening in short-axis slices of left ventricle from basis to apex. CMR-proved underlying heart disease were postinfarction heart failure, dilated cardiomyopathy and non-compaction cardiomyopathy in 62, 27 and in 11%, respectively. Mean left ventricular ejection fraction was 24.5±10%, intraventricular dyssynchrony was 200±78 ms. In four patients, requiring surgical revascularisation after unsuccessful coronary sinus electrode implantation, optimal position for epicardial screw-in electrode was selected. According to the results of CMR, biventricular device was not implanted in 7 patients. During the follow-up of the 38 patients, 5 patients (13.16%) were non-responders, despite the approximately 22% non-responder ratio in our whole patient population treated by CRT but without performing previous CMR examination. In this patient population CMR may have a significant role in the selection of responder patient population.

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