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Functional role of calcium-activated potassium (KCA) channels on the basal and agonist-elevated arterial tones was investigated in isolated rabbit aorta, porcine and canine coronary arteries as well as in human internal mammary artery. The vascular tones enhanced by contractile agents were increased further by preincubation of these conduit blood vessels with selective (charybdotoxin or iberiotoxin) or non-selective (tetraethylammonium) inhibitors of KCA channels. The basal tone (without an agonist) was increased only in the canine coronary artery. The results indicate a feed-back regulatory role of KCA channels counteracting the vasospasm of conduit arteries.

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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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Acta Alimentaria
Authors: M. Aloudat, A. Papp, N. Magyar, L. Simon Sarkadi, and A. Lugasi

The purpose of this study was to compare the energy content and macronutrients of forty main popular traditional and modern meals in both Jordan and Hungary with the national and international recommendations. The calculation of energy content and macronutrients were done on traditional and modern recipes by two different softwares (ESHA and NutriComp). Neither Jordanian nor Hungarian foods met the recommended energy content (35% of daily energy intake, 8400 kJ for energy intake). The recipes of both nations are characterised by higher protein, fat, and salt contents than WHO recommendation, a lower fibre content, and sugar content within the recommended limits. The fat energy ratio and saturated fatty acid content of Hungarian recipes are significantly higher than WHO recommendation. In general, Jordanian meals were more likely to meet the inclusion criteria. In conclusion, neither Jordanian nor Hungarian traditional and popular meals meet the international nutritional recommendations for a healthy diet, however, the composition of the real dishes may differ significantly from the recipes depending on the available ingredients and chosen kitchen technology.

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Journal of Thermal Analysis and Calorimetry
Authors: Gy. Marosi, P. Anna, Gy. Bertalan, A. Tohl, R. Lágner, I. Balogh, and I. Papp

Different levels of fibre technologies and application, from synthesis to degradation has been studied using the methods of thermal analysis. Recent results of these studies on synthetic and natural fibres are summarized. The effect of chemical and physical modification of polyolefin fibres as well as the synthesis of polymer emulsion used as additive in fibre technologies could be followed by DSC, DMA, TG methods.

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Earlier neurochemical studies suggested that human brain carboxypeptidase B may play a significant role in the degradation of amyloid-β1-42 in the brain. Using an immunohistochemical technique we report here on the neuronal expression and distribution of this enzyme in the segments (CA1a, CA1b and CA1c) of the CA1 subfield and in area CA4 of the hippocampus in normal and Alzheimer's disease brain samples. Its distribution was compared with the appearance of neurofibrillary tangles in the same brain sample. For immunohistochemical localization of carboxypeptidase B, a specific C14-module antibody was applied, together with the Gallyas silver impregnation technique for the demonstration of neurofibrillary tangles. The results revealed that, in the control samples, most of the immunoreactivity appeared in segment CA1a in the pyramidal cells, less in segment CA1b and least in segment CA1c. In the Alzheimer's disease samples, there was no particular immunostaining in the neurons, but, a large number of silver-impregnated degenerated neurons appeared. The results support the suggestion that carboxypeptidase B may play a significant role in elimination of the intracellular accumulation and toxicity of amyloid-β in the human brain and thereby protect the neurons from degeneration.

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Acta Biologica Hungarica
Authors: E. Horváth, G. Papp, Z. Gazdag, J. Belágyi, Á. Blaskó, J. Deli, Cs. Vágvölgyi, and M. Pesti

A carotenoid-less Phaffia rhodozyma mutant (MCP 325) exhibited significantly higher resistance to oxidative stressors such as menadione, H2O2 and K2Cr2O7 than its astaxanthin-producing parental strain (MCP 324). The absence of carotenoids in the mutant did not explain this phenomenon. The cause of the decreased superoxide, hydroxyl radical and glutathione contents, the increased peroxide concentration and the elevated specific activity of catalase under uninduced conditions may be a second mutation. Peroxide treatment induced specific catalase activity in the mutant but not in the parental strain. Regulation of these processes led to the result that, in spite of the mutations, the two strains exhibited the same multiplication rate and generation time.

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Acta Biologica Hungarica
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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Acta Biologica Hungarica
Authors: Eszter Virág, Á. Juhász, R. Kardos, Z. Gazdag, G. Papp, Ágota Pénzes, M. Nyitrai, Cs. Vágvölgyi, and M. Pesti

Interaction of primycin antibiotic with plasma membrane, and its indirect biological effects were investigated in this study. The antifungal activity of primycin against 13 human pathogenic Candida ATCC and CBS reference species and 74 other Candida albicans clinical isolates was investigated with a microdilution technique. No primycin-resistant strain was detected. Direct interaction of primycin with the plasma membrane was demonstrated for the first time by using an ergosterol-producing strain 33erg + and its ergosterol-less mutant erg-2. In growth inhibition tests, the 33erg + strain proved to be more sensitive to primycin than its erg-2 mutant, indicating the importance of the plasma membrane composition in primycin-induced processes. The 64 μg ml−1 (56.8 nM) primycin treatment induced an enhanced membrane fluidity and altered plasma membrane dynamics, as measured by steady-state fluorescence anisotropy applying a trimethylammonium-diphenylhexatriene (TMA-DPH) fluorescence polarization probe. The following consequences were detected. The plasma membrane of the cells lost its barrier function, and the efflux of 260-nm-absorbing materials from treated cells of both strains was 1.5–1.8 times more than that for the control. Depending on the primycin concentration, the cells exhibited unipolar budding, pseudohyphae formation, and a rough cell surface visualized by scanning electron microscopy.

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Acta Biologica Hungarica
Authors: L. Institóris, Dóra Kovács, I. Kecskeméti-Kovács, Anita Lukács, Andrea Szabó, Zsuzsanna Lengyel, A. Papp, L. Nagymajtényi, and I. Dési

Detectable interactions between NOEL (No Observed Effect Level) doses of Pb, Hg and Cd in general toxicological, hematological, and immune function parameters were investigated. The metals (Pb-acetate, 20 mg/kg; HgCl2, 0.40 mg/kg; CdCl2, 1.61 mg/kg) were combined. First, the rats received the combination Pb+Hg+Cd for 4 weeks per os. Significant difference vs. control was found only in the weight of lung and popliteal lymph node (PLN). The Pb+Hg and Pb+Cd combinations significantly decreased the PLN to 100 g body weight and PLN to brain weight ratio, and Pb+Hg also decreased the relative adrenal weight. After 12 weeks treatment with the same doses, effects on the thymus, kidney, and adrenal weights in the Pb+Hg, and thymus weight in the Pb+Cd, combination were seen. Pb+Cd also affected the white and red blood cell count and hematocrit. Combined with Hg or Cd, NOEL dose Pb showed toxicity, indicating that exposure limits may be inefficient in combined exposure situations.

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