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Scanning and transmission electron microscopic studies revealed the presence of slime-like, amorphous material on the surface of Schizosaccahromyces pombe RIVE 4-2-1 cells, independently, whether they were in flocculated or in non-flocculated state. Close contact of the adjacent cells via the merging outermost cell wall layers was found, however, only in the case of floc formation, which was induced by cultivating the cells in the presence of 6% (v/v) ethanol. Irreversible loss of the flocculation ability of the cells by treatment with proteinases suggests that proteinaceous cell surface molecules as lectins contribute to the cell-to-cell interaction during flocculation. Both proteinase K and pronase treatments removed a distinct outer layer of the cell wall, which indicated that the protein moieties of the phosphogalactomannan outer surface layer has a crucial role in the maintenance of cell wall integrity. In the case of lysing enzyme treatment the removal of the outermost layer was also observed as the first step of the cell wall digestion, while driselase treatment resulted in almost complete digestion of the cell wall.

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Ripeness: The colour of green (ripeness stage I), pit hardening (II), light red (a, b) (III, IV), red (V) and dark red (VI) sour cherry fruits ( Prunus cerasus cv. Kántorjánosi) were characterised by CIELAB L*, a* and b* values. L* and b* decreased as a function of ripeness, a* intensively increased between green (I) and pit hardening (II) stages. The cell wall of green fruit was intact, but the electron dense cytoplasm concentrated along the cell wall and showed a number of degradation signs. The pit hardening stage (II) resulted in more structural break down in the cytoplasm and in the cell wall. Large numbers of plastoglobuli were in the plastids resulting in chloroplast-gerontoplast conformation. The most striking feature of light red fruits is the dissolution of the walls. Middle lamellae almost completely disappeared. In ripe fruits, the wall degradation was even more prominent. The regular structure of the cytoplasm had almost completely disappeared. The total pectin content between pit hardening and light red stages was the highest. The autolysis of pectin increased between pit hardening (II) and light red-a stage (III), then it slowly decreased. The largest activity of β-galactosidase was in the green (I) stage, and then in the pit hardening stage (II) it suddenly decreased. In light red-a/b (III/IV) stages the activity of β-galactosidase again started to increase. The activity of polygalacturonase did not depend on the grade of ripeness. Storage: In the first period of storage, the activity of β-galactosidase and polygalacturonase of sour cherry decreased, then in the second period of storage increased.

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A new unstable organ-specific Adh1 mutant was isolated from autotetraploid S 25 Wf9 maize line after germinating kernels under water for two days. Adh1-Fm4x-1 expresses normal and/or reduced levels of ADH1 in anaerobic scutellum. No activity or approximately 33–75% of wild type level of ADH1 in pollen grains was observed. The organ-specific phenotype of the Adh1-Fm4x-1 could be maintained by selfing for ten subsequent generations. After crossing with the wild-type allele the Adh1 mutation transmitted to the next generation both by female and male gametophytes. The appearance of one- and two-banded patterns in anaerobic scutellum and pollen grains of heterozygous F 1 plants showed the lack of F·F homodimers.DNA sequence analyses of the wild type allele, the Adh1-Fm4x-1 mutant allele and four F 1 revertants revealed that the Adh1-Fm4x-1 mutation contains a Dissociation (Ds1) transposable element in the 5′ untranslated leader of the maize Adh1 gene, which regulates organ-specific expression at a quantitative level.

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Acta Alimentaria
Authors:
E. Kovács
,
P. Merész
,
Z. Kristóf
, and
E. Németh-Szerdahelyi

Colour, texture, pectin autolysis, membrane permeability and microstructure (SEM, TEM), β-galactosidase and polygalacturonase were studied in apricots (cv. Magyar kajszi) harvested in mature green, straw yellow, bright orange and deep orange stages. The L* increased from mature green to straw yellow then decreased from straw yellow to deep orange state. The a* values increased with ripening. The bright and deep orange apricots were significantly softer than the mature green and straw yellow ones and the membrane permeability increased with ripening. The presence of β-galactosidase enzyme was proved by immunoblotting analysis using monoclonal anti-β-galactosidase clone GAL-13 (Sigma) in all ripening stages. The enzyme activity was very low in mature green stage and increased significantly (P>95%) with increasing ripeness and during storage. The PG activity was very low in the mature green apricot. A significant (P>95%) increase was observed in the straw yellow apricot and in the riper fruits. The mature green apricot showed a regular, the straw yellow and bright orange samples showed a moderately regular tissue structure, while the tissue of the deep orange apricot collapsed (SEM). The cell wall and the middle lamella of the green apricot (TEM) were intact. Generally, there were intact cytoplasm membranes with some damaged parts. In the straw yellow apricot, the cell wall started to loosen, the middle lamella lost pectic polysaccharides. The structure of the cytoplasm was not recognisable, the tonoplast and the cytoplasm membrane were injured. The cell wall of the bright orange apricot was similar to that of the straw yellow ones. The middle lamella dissolved and hairy, fibrillar structure of cell wall was found in the deep orange samples.

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Colour (L*, a*, b*, h o and chroma), β-galactosidase, polygalacturonase (PG) activity, pectin content, ultrastructure and volatile compounds were determined, in mature green and in yellow ber fruits ( Zizyphus mauritiana Lamk. cv. Umran).The L* did not, but a*, b* and h o significantly differed between mature green and yellow ber fruit. The pectin content and its solubilization (soluble pectin and neutral sugars), the activity of PG was higher in yellow ber fruits and in the outer part of fruits. Activity of β-galactosidase was higher in mature green ber fruits. The cell walls of mature green fruits were usually homogeneous, the density of the middle lamellae decreased in yellow bers, and at the same time, the structure of chloroplastids disintegrated. The aroma of yellow ber is characterized by the presence of even carbon number of ethyl esters from C4 to C14.

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Acta Agronomica Hungarica
Authors:
J. Pauk
,
C. Lantos
,
G. Somogyi
,
P. Vági
,
Z. Ábrahám Táborosi
,
A. Gémes Juhász
,
R. Mihály
,
Z. Kristóf
,
N. Somogyi
, and
Z. Tímár

Spice pepper production has a history of almost 300 years in the southern part of Hungary. In this study the results of two biotechnological improvements are summarized. Anther and isolated microspore culture techniques were improved to release haploid and doubled haploid (DH) lines for spice pepper breeding. Both the anther and isolated microspore culture methods were successfully used in spice pepper haploid production. Microspore culture-derived structures were analysed to identify their different parts. Green plantlets were regenerated from embryos derived from both anther and microspore cultures. Their doubled haploid analogues were integrated into Hungarian spice pepper hybrid seed breeding programmes. One hybrid, Sláger, was released as a new genotype for spice pepper production in 2008 and two hybrid candidates (Délibáb and Bolero) are now being tested in official trials.

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Abstract

Introduction: The 2009 pandemic 2009 H1N1 (pH1N1) influenza A virus shows a markedly different disease pattern than seasonal strains, causing critical illness in relatively young, female, pregnant individuals as well as in comorbid patients. Materials and methods: The Department of Anesthesiology and Intensive Therapy of Semmelweis University served as a regional influenza center for the adult critically ill during the winter of pH1N1 outbreak. We analyzed data collected from 26 suspected pH1N1 critically ill patients treated in our unit during this period. Results: Sixteen cases were confirmed as pH1N1 infection with RT-PCR, while the other 10 patients with influenza like illness showed tendency to a different age and comorbidity, as well as outcome characteristics, suggesting a different pathogenesis. Confirmed pH1N1 patients showed a mean age of 50.5 years (median: 44; range: 20–85), with female predominancy (69%). Comorbidity was present in 69% of cases (chronic heart conditions, chronic pulmonary disease, previous history of malignancy present in 31; 25 and 19%, respectively). Twenty-five percent of the patients were pregnant women. Nineteen percent of the cases received previous pH1N1 vaccination. But two patients were later readmitted for worsening chronic conditions that led to death, which resulted in a total mortality rate of 31%. Mean APACHE II and SOFA scores on admittance were 12.2 and 5.3, respectively. Average length of treatment was 11.5 days (median: 6.5; range 2–50 days). All patients received ventilatory assistance, 69% of patients received invasive, while 31% of patients received non-invasive ventilatory assistance. The average number of days of invasive ventilation was 10.5 days (median: 5.5; range: 2–45). Forty-five percent of ventilated patients required rescue ARDS therapy. Complications included hemodynamic instability (56%); acute renal failure (13%) and pneumothorax (13%). Superinfection with other microbes were observed in 56% of the patients. Conclusions: In our study, pH1N1 infected critically ill patients had a wide age range, but were more commonly female, pregnant, or had a previously described underlying disease. Mortality, length of treatment, need for invasive mechanical ventilation, length of mechanical ventilation, major complication rates were similar to those previously described. A previously not reported relatively high occurrence of pneumothorax was noted, which is possibly a long-term complication of severe viral pneumonitis.

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