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The total viable cell count of bacteria in vacuum-packaged chilled minced beef has been decreased equally, by approx. two log-cycles, as an effect of 1.5-2.0 kGy gamma radiation or 200-300 MPa high hydrostatic pressure (UHP) treatment for 20 min. Coliform bacteria could be eliminated to non-detectable levels by the same treatments. The shelf-life of both untreated and non-thermally pasteurised samples were limited mainly by growth of lactic acid bacteria. At about equal bactericidal effect, more drastic changes of texture and colour occurred in UHP-pasteurized minced beef samples than in the radiation-pasteurized ones. Whereas radiation pasteurisation caused minimal changes in appearance, texture and DSC-thermograms of minced beef, UHP-pasteurisation of the raw samples proved to be strongly discolouring by denaturing the muscle pigments and causing extensive denaturation of the myofibrillar proteins. The water holding capacity of irradiated samples decreased, while that of high pressure treated ones increased as compared to the untreated control. Near infrared spectrometry and electronic nose measurements gave promising results to make distinctions non-destructively on changes of various physical-chemical changes and quality parameters as a function of pasteurising treatments and/or storage.
Thermal and HHP treatments were compared. We established that the applied HHP treatments reduced the total cell count more significantly than thermal treatments. For example, the 10 min 600 MPa/10 min HHP treatment was equivalent to about 10 min thermal treatment at 70 °C. This combination of temperature and time is not used in the pasteurisation practice of the dairy industry. The various thermal treatments reduce the phosphatase enzyme activity to between one-third and one-hundredth of the original activity. The HHP treatments yielded similar results. Six hundred MPa pressure caused 10 to 70% decrease in the enzyme activity, while 700 MPa pressure led to a decrease of one log cycle.In the second year we tried to investigate the kinetics of the effect of HHP treatment. The 5, 10, 20, 40 min holding times were systematically applied in the range of 400 to 700 MPa. According to the results, 600 and 700 MPa HHP treatments effectively assured a decrease in the total cell count and the alkaline phosphatase enzyme activity. No organoleptic changes occurred.
To check the importance of Cd-induced iron deficiency in Cd stress, symptoms of Cd stress were compared with those of iron deficiency or the combination of these two stresses. Poplar plants grown in hydroponics with Fe-EDTA (e) or Fe-citrate (c) up to four-leaf stage were treated for two weeks either by the withdrawal of iron (Fedef), or supplying 10 μM Cd(NO3)2 in the presence (Cad) or absence of an iron source (Fedef + Cad). Cadmium and iron content of leaves developing under the stress was in the order of cCad > eCad > cFedef + Cad and cCad ≈ eFedef ≈ cFedef + Cad < eCad < cFedef, respectively. Growth inhibition was much stronger in Cad than Fedef plants. The inhibitory effects on CO2 fixation, maximal and actual efficiency of PSII, chlorophyll synthesis, as well as the stimulation of the accumulation of violaxanthin cycle components and increase in non-photochemical quenching were the strongest in cFedef+Cad plants, otherwise these parameters changed parallel to the iron deficiency of leaves. Tendency of changes in thylakoid composition were similar under Cad treatments and strong iron deficiency: particularly PSI and LHCII decreased. Therefore, the development of the photosynthetic apparatus under Cd stress was mainly influenced by the Cd-induced strong iron deficiency, while leaf growth was affected primarily by the presence of Cd.
European eel is a catadromous fish species, which means that after living in freshwater premature individuals adapt to sea water, and migrate to the Sargasso Sea for spawning. Although male eel can be sexually matured even in freshwater, to date, it was believed that female eel can be matured only in seawater. Here we show that the process of sexual maturation may be induced in freshwater by treating female eels with carp pituitary (GSI = 9.87±1.55%). It is thus proposed that seawater condition is not an obligatory environment for stimulating gametogenesis and for artificial maturation of the European eel in neither gender.
In recent years an information system has been elaborated and constantly improved in Martonvásár, making it possible to handle the 3–4 million identification, observation, measurement, pedigree and other data generated for a total of almost 100,000 experimental plots each year. The extremely rapid development of biotechnology has made breeders interested in integrating molecular breeding methods into the conventional phenotype-pedigree system. The aim is to improve the competitiveness of breeding programmes through the intensive use of this new technology, with particular emphasis on determining how marker-assisted selection can be utilised. The present paper outlines not only a new data structure introduced to accommodate the new data elements of data categories such as gene sources, primer bank, primer combinations, markers, genes and alleles, but also data management tools and a standalone software interface to combine both molecular and phenotypic data. The integration of the molecular genomic data (GENETECH) with the information from the existing databases: pedigree (PEDIGREE), gene bank (GENEBANK) and germplasm exchange (GERMPEXCHG), ensures that biotechnological data generated at no little cost can be harnessed in ways that are important for breeders in decision-making. This is achieved through: (i) identification and centralization in uniform sources of the molecular data, and their matching with specific phenotypes, with special regard to those of importance for marker-assisted selection, (ii) integration and compliance with existing information system data, (iii) facilitation of decision-making based on the above (e.g. grouping of selection/crossing partners).
The research institute in Martonvásár is one of the largest agricultural research institutes in Hungary and in Central Europe. For many years now, the accumulated data on the extensive wheat breeding stocks has been handled and analysed using programs developed in the institute. The information system that has been elaborated and constantly improved can be used for keeping records of breeding stock, for planning field and laboratory experiments, for site-plant performance evaluation, for automated data collection, for the rapid evaluation of the results and for effective management of the pedigree, seed exchange and the institute’s cereal gene bank.The demand for the storage of molecular data and their use in breeding has increased parallel with the development of new, PCR-based markers. For this reason, informatics tools (data structure and software) suited to the design of marker-assisted selection experiments and the interpretation of the results have been developed as part of the existing Martonvásár wheat breeding information system. The aim was to link molecular data to the phenotypic information already available in the database and to make the results available to wheat breeders and geneticists.The interpretation of molecular data related to specific genotypes is of assistance in clarifying the genetic background of economically important phenotypic traits, in identifying markers linked to the useful genes or agronomic traits to be found in the genomics database, and in the selection of satisfactory parental partners for breeding. Marker assisted selection coupled with traditional breeding activities enables the breeder to make plant selections based on the presence of target genes. Conventional wheat breeding with the integrated molecular component allows breeders to more accurately and efficiently select defined sets of genes in segregating generations.The molecular data are stored in a relational database, the central element of which is the [DNASource] entity. This is used to collect and store information on gene sources arising during breeding. It is therefore linked both to the phenotypic data stored in the traditional breeding system (measurements, observations, laboratory data) and to the component parts of the new, molecular data structure ([PrimerBank], [Marker], [Allele] and [Gene]).
A total of 96 winter wheat ( Triticum aestivum L.) cultivars registered in Hungary were analysed using 15 wheat microsatellite markers located on different chromosome arms. Analyses revealed 91 SSR alleles with sizes ranging from 123–239 base pairs. The total number of alleles per locus ranged from 2 (Gwm664 and Gwm415) to 11 (Gwm219) with an average number of 6.1. The polymorphic information content (PIC) values ranged from 0.06 to 0.85 with an average number of 0.60 for all markers. Several markers included allele sizes characteristic of a single or a small number of cultivars. At most 9 SSR markers were required to distinguish the 96 cultivars, so the simple sequence repeats could serve as a relatively cheap, rapid method for identifying winter wheat cultivars.
Purpose
Reduced functional mobility is a risk factor for falls. The Timed Up and Go test is a complex measurement tool for functional mobility. Our aims were to assess the functional mobility of: (a) community-living elderly who were participating in an exercise programme (n = 40; mean age = 73.7 years), (b) community-living elderly who were physically inactive (n = 40; mean age = 74.1 years), and (c) institutionalized elderly (n = 40; mean age = 73.5 years) and to compare the results with cut-off values for risk of fall.
Materials and methods
After measuring functional mobility, one-way independent ANOVAs and sample t-tests were used for analysis.
Results
The functional mobility of the active participants was better than that of the inactive (p < .001) and institutionalized participants (p < .001). There was no significant difference between the inactive and institutionalized participants (p = .990). The functional mobility of the active participants was better, whereas the functional mobility of the inactive participants was worse than the cut-off value of 13.5 s for risk of fall for community-living elderly. The functional mobility of the institutionalized participants did not differ from the 15-s reference value for predicting risk of fall.
Conclusion
The results indicate that regular physical activity has a positive effect on maintaining functional mobility among both community-living and institutionalized elderly individuals.
Research with transgenic plants in the Agricultural Research Institute of the Hungarian Academy of Sciences is primarily related to applications that are essential for the genetic improvement of cereals. The two main directions are connected to wheat and maize breeding and are focused on improving agronomic and nutritional traits. This paper highlights experiments in these areas, which are conducted in national as well as international collaborations. The transparency of this work is ensured by the dissemination of information about approved confined field tests to the public via the internet.
