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Acta Alimentaria
Authors:
Cs. Dobolyi
,
K. Inotai
,
I. Bata-Vidács
,
D. Sárkány
,
O. Csernus
,
S. Kocsubé
,
B. Tóth
,
A. Szekeres
, and
J. Kukolya

Abstract

Aspergillus strains were isolated from Hungarian mills in order to get information on the appearance of sterigmatocystin (ST) producing moulds, whose presence has never been demonstrated in Hungary. Fungal isolates were classified into nine morphotypes, sections Nigri, Nidulantes, Versicolores (two morphotypes), Circumdati, Flavi (two morphotypes), Clavati and Terrei by classical mycological assays. ST producing strains could be classified into section Versicolores. ST production of the isolates was assessed by liquid and solid phase growth experiments and compared to ST producing reference strains: Aspergillus pepii SzMC 22332, Aspergillus versicolor SzMC 22333, Aspergillus griseoaurantiacus SzMC 22334 and Aspergillus nidulans RDIT9.32. Four of our isolates marked as Km11, Km14, Km26 and Km31 showed ST production in liquid medium. ST production on solid phase corn grit substrate was measured after three weeks of incubation, and Km26 isolate proved to be the most prominent with a toxin concentration of 277.1 μg g−1, surpassing all reference strains. The toxin-producing ability of Km26 isolate was also tested in a field experiment, where corn was infected. By the end of the experiment, ST level of 19.56 μg kg−1 was measured in infected corn.

Molecular taxonomic identification of the Km26 strain was performed using internal transcribed spacer (ITS), calmodulin and tubulin sequence analyses. Based on these studies, strain Km26 was identified as Aspergillus creber.

Here we report that an ST-producing A. creber strain has appeared in Hungary, and the Km26 strain is the first known extreme ST-producing mould in this country. As a result of climate change, aflatoxin B1 producing Aspergillus flavus strains have appeared in Hungary in the last decade. As strain Km26 is the only A. creber isolate in Hungary so far, there is no sign of mass prevalence, and due to the lower temperature optimum of the species compared to A. flavus, its appearance is probably not related to climate change.

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Acta Alimentaria
Authors:
B. Csehi
,
E. Szerdahelyi
,
K. Pásztor-Huszár
,
B. Salamon
,
A. Tóth
,
I. Zeke
,
G. Jónás
, and
L. Friedrich

In the experiments pork loin and beef sirloin were treated by pressures of 100 to 600 MPa by 100 MPa steps for 5 min. Colour changes of samples and the changes of proteins were investigated. The latter were examined with isoelectric focusing and SDS polyacrylamide gel electrophoresis. We found that myoglobin behaved completely differently in case of the two different species. Myoglobin has mostly lost its native state at 300 MPa pressure in case of pork, but the beef myoglobin could remain native even up to 500 MPa. The treatment at 300 MPa or higher pressure values caused almost complete aggregation and denaturation in case of pork and beef proteins. The results of SDS-PAGE and the colour measurement confirmed this finding.

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Abstract  

Within the frame of a joint project, the accumulation of the uranium and transuranium (TRU) species on some structural materials used at Soviet made VVER-type pressurized water reactors (such as heat exchanger tube of steam generators and stainless steel canister material) has been studied. The experiments were carried out in a laboratory model system. During the sorption studies, boric acid coolants provided by the Paks Nuclear Power Plant (Paks NPP) were circulated for a period of 30 h. Solution and tube samples obtained in the course of above experiments were analyzed by independent methods (α- and γ-spectrometry, ICP-MS, SEM-EDX, voltammetry and XPS). The experimental results reveal that: (i) the surface excess of the TRU nuclides studied is extremely low (less than 1% of a monolayer coverage); (ii) the surface excess of uranium species measured on the SG tube surfaces is significantly higher, after 30 h sorption period (Γsample = 1.0 μg cm−2 U ≅ 3.7 × 10−9 mol cm−2 UO2) exceeds a monolayer coverage; (iii) the mechanistic features of the contamination processes (specific or non-specific adsorption, deposition of colloidal and/or disperse particles) depend decisively upon the nature of the studied radionuclides and the chemical structure and composition of the oxide layer formed on stainless steel surfaces.

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Traps baited with pear ester + acetic acid were capable of monitoring the codling moth although caught fewer specimens than pheromone baited traps. The general flight patterns recorded in pear ester + acetic acid baited traps resembled closely those recorded with pheromone traps. The only aspect in which pear ester + acetic acid baited traps lagged behind was early detection of first moth specimens occurring in the season. The great advantage of traps with pear ester + acetic acid over pheromone traps was that the former caught females in a high percentage. Further studies are needed to determine whether the sex ratio recorded in captures resembles reliably the natural sex ratio of the given population, or it is distorted. It appears that traps baited with pear ester + acetic acid present a useful alternative for monitoring codling moth especially in mating disruption treated orchards where pheromone traps do not work, or in any other situations where for any reason the capture of female codling moths is sought for. The lower efficiency of the pear ester + acetic acid bait can easily be overcome by applying more traps for monitoring at a given site.

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Acta Phytopathologica et Entomologica Hungarica
Authors:
M. Tóth
,
J. Jósvai
,
K. Hári
,
B. Pénzes
,
Zs. Vuity
,
I. Holb
,
I. Szarukán
,
Zs. Kecskés
,
I. Dorgán-Zsuga
,
S. Koczor
, and
E. Voigt

For acceptable capture efficiency it was necessary to add acetic acid to pear ester for successful trapping of codling moth populations in Hungary. The activity of pear ester on its own was very weak and unsatisfactory. Pear ester+acetic acid baited traps caught on an average 25% (mean of 6 tests) of the catch in pheromone traps. Traps with pear ester+acetic acid were clearly advantageous as compared to pheromone traps in that they caught not only males but also females (both virgins and mated) in a high percentage. Traps baited with pear ester+acetic acid clearly outperformed high-load pheromone lures in orchards with mating disruption and should be the right choice for the grower for sampling populations of codling moth in a mating disruption situation. In orchards with no mating disruption the relative inefficiency of pear ester+acetic acid baited traps as compared to pheromone traps can easily be overcome by applying more traps than usual. Thus the overall codling moth numbers caught will become higher and would make any conclusions drawn more reliable. Traps baited with pear ester+acetic acid always caught more when set at the highest branches (3.0–3.5 m) than when set lower (1.5–1.8 m) on trees.

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Acta Botanica Hungarica
Authors:
P. Török
,
E. Tóth
,
K. Tóth
,
O. Valkó
,
B. Deák
,
B. Kelbert
,
P. Bálint
,
Sz. Radócz
,
A. Kelemen
,
J. Sonkoly
,
T. Miglécz
,
G. Matus
,
A. Takács
,
V. A. Molnár
,
K. Süveges
,
L. Papp
,
L. Papp Jr.
,
Z. Tóth
,
B. Baktay
,
G. Málnási Csizmadia
,
I. Oláh
,
E. Peti
,
J. Schellenberger
,
O. Szalkovszki
,
R. Kiss
, and
B. TÓthmérész

For understanding local and regional seed dispersal and plant establishment processes and for considering the ecotypes and other forms of specific variability, hard data of locally or regionally measured traits are necessary. We provided newly measured seed weight data of 193 taxa, out of which 24 taxa had not been represented in the SID, LEDA or BiolFlor databases. Our new measurements and formerly published data of locally collected seed weight records together covers over 70% of the Pannonian flora. However, there is still a considerable lack in seed weight data of taxonomically problematic genera, even though they are represented in the Pannonian flora with a relatively high number of species and/or subspecies (e.g. Sorbus, Rosa, Rubus, Crataegus and Hieracium). Our regional database contains very sporadic data on aquatic plants (including also numerous invasive species reported from Hungary and neighbouring countries) and some rare weeds distributed in the southwestern part of the country. These facts indicate the necessity of further seed collection and measurements.

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Acta Botanica Hungarica
Authors:
R. Kiss
,
J. Sonkoly
,
P. Török
,
B. Tóthmérész
,
B. Deák
,
K. Tóth
,
K. Lukács
,
L. Godó
,
A. Kelemen
,
T. Miglécz
,
Sz. Radócz
,
E. Tóth
,
N. Balogh
, and
O. Valkó

Seeds ensure the survival and dispersal of the majority of vascular plant species. Seeds require species-specific germination conditions and display very different germination capacities using different germination methods. Despite the importance of plant generative reproduction, little is known about the germination capacity of the seeds of the Pannonian flora, particularly under field conditions. Our aim was to reduce this knowledge gap by providing original data on the germination capacity of 75 herbaceous species. We reported the germination capacity of 8 species for the first time. We also highlighted the year-to-year differences in the germination capacity of 11 species which could be highly variable between years. The data regarding the germination capacity of target species, as well as weeds and invasive species, can be informative for nature conservation and restoration projects. Our findings support the composition of proper seed mixtures for ecological restoration and also highlight the importance of testing seed germination capacity before sowing.

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Cereal Research Communications
Authors:
T. Tóth
,
T. Németh
,
A. Bidló
,
F. Dér
,
M. Fekete
,
T. Fábián
,
Z. Gaál
,
B. Heil
,
T. Hermann
,
E. Horváth
,
G. Kovács
,
A. Makó
,
F. Máté
,
K. Mészáros
,
Z. Patocskai
,
F. Speiser
,
I. Szűcs
,
G. Tóth
,
Gy. Várallyay
,
J. Vass
, and
Sz. Vinogradov
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Physiology International
Authors:
Zs. Sári
,
T. Kovács
,
T. Csonka
,
M. Török
,
É. Sebő
,
J. Toth
,
D. Tóth
,
E. Mikó
,
B. Kiss
,
D. Szeőcs
,
K. Uray
,
Zs. Karányi
,
I. Kovács
,
G. Méhes
,
P. Árkosy
, and
P. Bai

Abstract

Breast cancer is characterized by oncobiosis, the abnormal composition of the microbiome in neoplastic diseases. The biosynthetic capacity of the oncobiotic flora in breast cancer is suppressed, as suggested by metagenomic studies. The microbiome synthesizes a set of cytostatic and antimetastatic metabolites that are downregulated in breast cancer, including cadaverine, a microbiome metabolite with cytostatic properties. We set out to assess how the protein expression of constitutive lysine decarboxylase (LdcC), a key enzyme for cadaverine production, changes in the feces of human breast cancer patients (n = 35). We found that the fecal expression of Escherichia coli LdcC is downregulated in lobular cases as compared to invasive carcinoma of no special type (NST) cases. Lobular breast carcinoma is characterized by low or absent expression of E-cadherin. Fecal E. coli LdcC protein expression is downregulated in E-cadherin negative breast cancer cases as compared to positive ones. Receiver operating characteristic (ROC) analysis of LdcC expression in lobular and NST cases revealed that fecal E. coli LdcC protein expression might have predictive values. These data suggest that the oncobiotic transformation of the microbiome indeed leads to the downregulation of the production of cytostatic and antimetastatic metabolites. In E-cadherin negative lobular carcinoma that has a higher potential for metastasis formation, the protein levels of enzymes producing antimetastatic metabolites are downregulated. This finding represents a new route that renders lobular cases permissive for metastasis formation. Furthermore, our findings underline the role of oncobiosis in regulating metastasis formation in breast cancer.

Open access
Acta Physiologica Hungarica
Authors:
G.Zs. Toth
,
Adam Tarnoki
,
D.L. Tarnoki
,
A. Racz
,
Z. Szekelyhidi
,
L. Littvay
,
K. Karlinger
,
A. Lannert
,
A.A. Molnar
,
Zs. Garami
,
V. Berczi
,
I. Suveges
, and
J. Nemeth

Spherical equivalent (SE) has not been linked to increased cardiovascular morbidity.

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