Search Results

You are looking at 11 - 20 of 72 items for

  • Author or Editor: K. Kiss x
  • Refine by Access: All Content x
Clear All Modify Search

Functional morphology of Helix pomatia salivary gland cells was studied at light microscopic level by using different histochemical methods. Three cell types could be demonstrated in the salivary gland: mucocytes, granular and vacuolated cells. The distribution and the number of the different cell types were different in active and inactive snails. In active feeding animals, dilatated interlobular salivary ducts were observed, which were never present in inactive ones. In active animals an additional cell type, the cystic cell could also be observed. Periodic acid Schiff staining revealed both mucuos and serous elements in the salivary gland. Furthermore, hematoxyline-eosin staining indicated the occurrence of a cell layer with high mitotic activity in the acini. Applying immunohistochemical methods with monoclonal mouse anti-human Ki-67 clone, B56 and polyclonal rabbit anti-human Ki-67 antibodies, we also were able to demonstrate the occurrence of dividing cells in the salivary gland. Analysis of 1-2 µm semi-thin Araldite sections stained with toluidine-blue showed that the saliva can be released, in addition to possible exocytosis, by the lysis of cystic cells. Using an apoptosis kit, we could also establish that this process was due to rather an apoptotic than a necrotic mechanism. In the salivary gland of active snails, where an intensive salivation takes place, significantly more apoptotic cells occurred, if compared to that of inactive animals. It is suggested that programmed cell death may also be involved in the saliva release.

Restricted access

The ultrastructure, neuroanatomy and central projection patterns, including the intercellular connections of the statocyst hair cells of the pond snail, Lymnaea stagnalis, were studied, applying different intra- and extracellular cellular staining techniques combined with correlative light- and electron microscopy. Based on the ultrastructure different hair cells could be distinguished according to their vesicle and granule content, meanwhile the general organization of the sensory neurons was rather uniform, showing clearly separated perinuclear and “vesicular” cytoplasmic regions. Following intra- and extracellular labeling with fluorescence dyes or HRP a typical, local arborization of the hair cells was demonstrated in the cerebral ganglion neuropil, indicating a limited input-output system connected to the process of gravireception. Correlative light- and electron microscopy of HRP-labeled hair cells revealed both axo-somatic and axo-axonic output contacts of hair cell varicosities, and input on sensory axons located far from the terminal arborizations. Our findings suggest (i) a versatile ultrastructural background of hair cells corresponding possibly to processing different gravireceptive information, and (ii) the synaptic (or non-synaptic) influence of gravireception at different anatomical (terminal, axonal and cell body) levels when processed centrally. The results may also serve as a functional morphological background for previously obtained physiological and behavioral observations.

Restricted access
Restricted access
Acta Botanica Hungarica
Authors:
B. Bolla
,
G. Fehér
, and
K. Kiss
Restricted access

DSC studies on the polymorphism and pseudopolymorphism of pharmaceutical substances

A complex system for studying physico-chemical behaviour of binary mixtures

Journal of Thermal Analysis and Calorimetry
Authors:
K. Marthi
,
M. Ács
,
G. Pokol
,
K. Tomor
, and
K. Eröss-Kiss

A complex system including thermoanalytical methods, infrared spectroscopy and X-ray powder diffraction for studying physico-chemical behaviour of binary mixtures is described. This system has been tested by investigating binary mixtures of amphetamine hydrochloride salts.

Restricted access

Benthic diatom investigations of some Hungarian streams have been carried out in order to find reference sites in assistance to the ecological quality analysis of the different river types according to the Hungarian river typology. On the basis of the coevaluation of biological and chemical parameters, among the investigated streams, some part of Kemence stream seems to be the appropriate reference site for the classification of the highland, siliceous rivers of Hungary. However, further invastigations are needed for the selection of reference sites for the other types of Hungarian river typology. This is the most difficult in the case of lowland rivers, which are exposed to more severe anthropogenic impacts. Important is the question which biological parameters should be investigated and considered when assessing the ecological condition of our waters. In the United States, e.g. the assessment of the relative abundance of Achnanthidium minutissimum is quite widespread (Stevenson and Bahls 1999), the extent of which indicates the level of disturbance. The use of this method is hampered, on one hand, by the fact that A. minutissimum is an early coloniser species which means that if we do not take samples from mature periphyton, we might find it dominant simply because of that, and, on the other hand, that distinguishing between the species varieties is not always unambiguous under light microscope because of its small size, and these can have different ecological needs. It is also recommended to calculate species richness, diversity and evenness (Stevenson and Bahls 1999), but based on our investigations these parameters are not in correlation with water quality. Investigation of other diatom features such as tolerance and sensitivity, some autecological parameters (as it was applied and recommended by Fore and Grafe 2002 for investigating the reaction of diatom associations to anthropogenic disturbances) might also be useful in completing the water quality analysis of rivers, however, these methods need further investigations. Some of the indices (EPI-D, IPS, IBD) calculated with the software Omnidia are suitable for the classification of our rivers, but the investigation of more rivers, flowing through different types of stone are necessary to choose the appropriate indices. The reason for this is that the different indices work with a different register of species and obviously those indices will prove to be suitable the species register of which shows the highest similarity to the diatom associations of the certain water type.

Restricted access
Acta Botanica Hungarica
Authors:
Á. K. Kiss
,
L. Gy. Szabó
, and
K. Szabó

Komárek, J. and Anagnostidis, K. (2005): Cyanoprokaryota. 2. Teil: Oscillatoriales. - In: Büdel, B., Krienitz, L., Gärtner, G. and Schagerl, M. (eds): Süßwasserflora von Mitteleuropa, Band 19/2. Spektrum Akademischer Verlag, Elsevier GmbH, München, 759 pp.; Ross, I. A. (2005): Medicinal plants of the world - chemical constituents, traditional and modern medicinal uses. Volume 3. - Humana Press, Totowa, New Jersey, 623 pp. (ISBN 1-59259-887-0); Siver, P. A., Hamilton, P. B., Stachura-Suchoples, K. and Kociolek, J. P. (2005): Diatoms of North America: The freshwater flora of Cape Cod, Massachusetts, U.S.A. - In: Lange-Bertalot, H. (ed.): Iconographia Diatomologica. Annotated Diatom Micrographs. Vol. 14. A. R. G. Gantner Verlag K. G. Ruggel, 463 pp.;

Restricted access

Consumption of dietary supplements (DS) has been showing a persistent, rapidly growing tendency all over the world. A new branch has been created on the borderline of food and pharmaceutical industries. It is a general tendency that the policy and regulation towards the products of this branch are lagging far behind the practice. This is an especially important problem with adolescents. To work out an efficient regulatory framework, we have to have an adequate picture on consumer behaviour and attitudes towards these products. Based on literature analysis of two focus group interviews, we have developed a motivational model on usage of DS, which has been tasted during a direct-question survey involving more than 500 respondents. Our results have proven that the consumption of DS is proliferated among young recreational athletes. One quarter of them consumes proteins, one tenth L-carnitine at least 2–3 times a week. The most important motivational factor is the improvement of sport performance. The level of confidence in these products is considerably influenced by peers and trainers. The propensity to underestimate the potentially adverse consequences of these products is high.

Restricted access

In the present paper two species of leafhoppers (Cicadomorpha, Cicadellidae) are reported for the first time from Hungary. Both species were collected from ornamental plants along highway margins in the vicinity of Budapest. Liguropia juniperi (Lethierry, 1876) has already been reported from several European countries. Opsius smaragdinus Emeljanov, 1964 has only been previously reported from Ukraine and Asian part of Turkey.

Restricted access