carrier state is almost general in men. The virus induces B lymphocyte
but this is counteracted
immune response. Therefore, EBV-induced malignancies occur only when the immune
response is impaired, e.g. in transplant recipients. The versatility of the viral gene expression strategy
secures the consistent maintainance of the virus in healthy individuals. The
viral proteins required for transformation render the cell immunogenic.
Expression of the transforming genes leads to rejection, but these genes are
not required for the maintenance of the viral genome. EBV is an important
contributor for malignant transformation, even when it does not directly induce
cell proliferation. Several mechanisms have been unravelled in EBV-associated
tumors whereby the virus may modify the cellular phenotype and may influence
the interaction of tumor cells with their microenvironment. The virus carrier
state can lead to the evasion of apoptosis and can intensify the response to
growth promoting signals, too.
Authors:Zs. Révay, T. Belgya, L. Szentmiklósi, and Z. Kis
The PGAA facility at the Budapest Research Reactor has been continually upgraded and developed since its start-up in 1996,
as a result of which its performance has improved considerably. The installation of the cold neutron source, the partial change
to supermirror neutron guides and their realignment increased the flux by almost two orders of magnitude. The data acquisition
has been modernized as well; digital spectrometers were tested and implemented in novel forms of gamma-ray spectrum collection.
This year a higher-efficiency HPGe detector and a new data acquisition module were put into operation. Most recently all the
neutron guides were changed to supermirror-coated ones to further increase the neutron flux. The improved evaluation software
makes possible a more reliable elemental analysis of the samples. In this progress report these developments are critically
reviewed. The characteristics of the latest system are also described. It is the first time that a set of new partial gamma-ray
production cross sections are presented, which are based on the new intensity values of 14N(n,γ)15N calibration standard.
Authors:L. Szentmiklósi, Zs. Révay, T. Belgya, A. Simonits, and Z. Kis
The off-line γ-counting of in-beam activated radionuclides has been explored to extend the detection capabilities of prompt
gamma activation analysis (PGAA). Such combination of the prompt measurement with a subsequent decay-counting is feasible
if radionuclides with half-lives of minutes or hours are produced in the sample during neutron irradiation. Thanks to the
simpler spectrum and the higher counting efficiency of decay counting, both selectivity and sensitivity can be improved. The
pros and cons of the proposed method have been demonstrated on a series of industry-related measurements.
Authors:Gy. Györe-Kis, K. Deák, A. Lugasi, A. Csúr-Vargaa, and L. Helyes
A three years (2008, 2009, and 2011) open field experiment was conducted to study the effect of growing methods (organic and conventional) on the tomato yield components (Brix°, carbohydrate, organic acid, lycopene, and total polyphenols). Significantly higher Brix°, carbohydrate-, and lycopene content was found in conventional production. In spite of this, total phenolic content of tomato fruits was significantly higher in organic production. Our experiences show that it is probable, that the techniques used in the cultivation of organic crops — no artificial nutrients — could activate natural defence mechanisms in tomato plants, by increasing content of total polyphenol in the fruits.
Authors:T. Belgya, Z. Kis, L. Szentmiklósi, Zs. Kasztovszky, G. Festa, L. Andreanelli, M. De Pascale, A. Pietropaolo, P. Kudejova, R. Schulze, and T. Materna
Prompt gamma activation analysis (PGAA) is a well known tool for non-destructive bulk elemental analysis of objects. The measured
concentrations are only representative of the whole sample if it is homogenous; otherwise it provides only a sort of average
composition of the irradiated part. In this latter case one has to scan the sample to obtain the spatial distribution of the
elements. To test this idea we have constructed a prompt gamma activation imaging — neutron tomograph (PGAI-NT) setup at the
NIPS station of the Budapest Research Reactor, consisting of a high-resolution neutron tomograph and a germanium gamma-spectrometer.
The samples are positioned relative to the intersection of the collimated neutron beam and the projection of the gamma-collimator
(isocenter) by using an xyzω-moving table.
Authors:T. Belgya, Z. Kis, L. Szentmiklósi, Zs. Kasztovszky, P. Kudejova, R. Schulze, T. Materna, G. Festa, and P. Caroppi
The European collaboration “ANCIENT CHARM” (http://ancient-charm.neutron-eu.net/ach/) aims to develop new non-destructive neutron techniques to image the internal composition of complex archaeological objects
in order to answer various archaeological questions. Among these techniques, prompt gamma activation imaging (PGAI) and neutron
tomography (NT) form a unique combination which can determine the 3D distribution of most elements in objects with a non-destructive
procedure. A spatial resolution better than 2 mm has already been achieved in a moderately scattering matrix material.
Authors:M. Antal, A. Regöly-Mérei, L. Biró, K. Nagy, J. Fülöp, E. Beretvás, E. Gyömörei, O. Kis, and A. Vámos
This study investigates the nutritional status, life-style practices, serum vitamin D and bone density of adolescents. A total of 326 adolescents, aged between 11 and 14 years, were involved in the present examination: after winter 110 boys and 97 girls (March 2002 and February 2003), and after summer 66 boys and 53 girls (October 2002 and 2003) were investigated. Energy and nutrient intake and life-style practices were assessed. Body mass and height were measured, body mass index was calculated. Serum concentration of 25-hydroxyvitamin D [25(OH)D] was determined. Bone mineral density of calcaneus was measured. Protein intake was higher than the Hungarian RDA. All of the students had vitamin D intake far below the RDA, 33.3% of boys and 43.2% of girls had Ca intake below 70% of RDA, and sodium intake was more than twice higher than the RDA. After winter, 2% of boys and 8% of girls were considered vitamin D deficient and 11% and 19% vitamin D insufficient, respectively. After summer, 24% of boys and 21% of girls had 25(OH)D level over the reference range. The mineral content of bone was insufficient in 12.9% of boys and 10.4% of girls, respectively. The majority of the students had physical activity only in school, incorporated in the timetable.
Authors:D. Virok, Z. Kis, L. Kari, P. Barzo, R. Sipka, Katalin Burian, D. E. Nelson, Marta Jackel, T. Kerenyi, M. Bodosi, Eva Gönczöl, and Valeria Endresz
The aim of our study was to investigate the combination of Chlamydophila pneumoniae and human cytomegalovirus (HCMV) as a pathogenic factor in atherosclerosis. Accordingly, we tested by means of PCR and immunohistochemistry the presence of these pathogens in the same atherosclerotic carotid specimen. The histology of the samples and the patients' antibodies against these pathogens were evaluated. Further, we examined the impact of C. pneumoniae and HCMV infection on the gene expression of the human monocytic cell line U937. Six of the 22 samples contained only C. pneumoniae, 4 contained only HCMV, 7 contained both C. pneumoniae DNA and/or antigens of both pathogens, and 5 samples were negative. No correlation was found between the presence of these microbes and either the cellular structure of the plaques, or the serostatus of the patients. The infection of U937 cells with HCMV and especially C. pneumoniae induced inflammation and atherosclerosis-related genes. Furthermore, the doubly-infected cells produced higher levels of the mRNA of pro-platelet basic protein and fatty acid binding protein 4. In conclusion, C. pneumoniae is often present in combination with HCMV in atherosclerotic carotid lesions. The in vitro coinfection model reveals that the doubly-infected monocytes are potent expressors of proatherosclerotic genes, suggesting that this coinfected population may accelerate the process of atherosclerosis.
Authors:A. Ádám, P. Bencze, J. Bór, B. Heilig, Á. Kis, A. Koppán, K. Kovács, I. Lemperger, F. Märcz, D. Martini, A. Novák, G. Sátori, S. Szalai, L. Szarka, J. Verő, V. Wesztergom, and B. Zieger
The paper describes research in geomagnetism and aeronomy carried out in the framework of a project organized by the Geodetic and Geophysical Research Institute of the Hungarian Academy of Sciences. It includes the development of the instrumentation of the Nagycenk Geophysical Observatory (geomagnetic measuring systems, ionosonde), moreover other instrumental and methodological developments, too. Observatory data are available in a database. Based on results of the Nagycenk and Tihany observatories and on data of permanent and temporal networks, long-term trends of different electromagnetic parameters were investigated. Thus geomagnetic activity was found secularly increasing, a decrease of the atmospheric electric potential gradient and a 11-year modulation of the winter/December attenuation of the geomagnetic pulsation activity were confirmed. Several possibilities (pulsations, whistlers, modelling) were used to improve knowledge about structure and parameters of the magnetosphere. Electromagnetic precursors of earthquakes were looked for. A significant increase of understanding was obtained in connection with Schumann resonances and electromagnetic transients caused by lightning. It was shown that see-coasts influence characteristically changes in ionospheric trends (
F2). When looking for the effect of the global climate changes in the subsurface electric resistivity, an example was discovered for the decrease of the resistivity due to infiltrating water from precipitation. Electromagnetic exploration of tectonically conditioned weak zones was continued, too.