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1

The effect of undecaprenol on bilayer lipid membranes

100%
Janas T., Chojnacki T., Swiezawska E., Janas T.
Acta Biochimica Polonica
|
1994
|
tom 41
|
nr 3
The influence of undecaprenol on phosphatidylcholine macrovesicular bilayer lipid membranes has been studied by electrophysiological techniques. The current-voltage characteristics/ ionic transference numbers, the membrane conductance-temperature relationships and the membrane breakdown voltage were measured. The permeability coefficients for Na+ and Cl~ ions, the activation energy of ion migration across the membrane, the membrane hydrophobic thickness and the membrane Young's modulus were determined. Undecaprenol increases membrane conductance, membrane capacitance, membrane ionic permeability and membrane elastic deformability, decreases the activation energy, membrane hydrophobic thickness and membrane electromechanical stability, and does not change membrane selectivity. The formation by undecaprenyl molecules of fluid microdomains modulating membrane hydrophobic thickness is postulated. The data suggest that the behaviour of undecaprenol in membranes is regulated by transmembrane electrical potential.
2

Electric changes in callus tissue during differentiation and regeneration

75%
Filek M.
Acta Physiologiae Plantarum
|
1997
|
tom 19
|
nr 2
3

The electrolyte barrier of the gastric mucosa and the barrier breakers

75%
Szlachcic A., Dziadus-Sokolowska A.
Biophysics of Membrane Transport
|
1994
|
tom 12
|
nr 2
4

Light-induced changes in stem circumnutations and electrical potential in Helianthus annuus L.

75%
Stolarz M., Zawadzki T., Krol E., Dziubinska H., Krupa M., Buda A., Trebacz K.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr Suppl.
5
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Ways of signal transmission and physiological role of electrical potentials in plants

75%
Dziubinska H.
Acta Societatis Botanicorum Poloniae
|
2003
|
tom 72
|
nr 4
Plants are subject to stimuli from the environment on which they strongly depend and in contrast to animals, they are unable to escape harmful influences. Therefore, being able to receive stimuli they have developed adequate responses to them. Such a reaction can occur in the area of a stimulus action or cover the whole plant or its parts. In the latter case, it is a systemic reaction. The plant reaction is expressed by various intensity, rate and kind of response. It is interesting to know the character of the signal informing about a stimulus, the routes of its propagation and the transmission mechanism. Three conceptions of excitation are distinguished: 1) propagation of chemical agents formed at the site of a stimulus action with the flow of the phloem sap or through the atmosphere (in the case of volatile substances) to other plant parts, 2) a very fast transmission by the xylem in the wave of hydraulic pressure formed after a plant damage. From combining the "hydraulic" and "chemical" hypothesis a conception of hydraulic dispersion has been formulated which assumes that chemical substances synthetized after an injury can be transferred very fast with the wave of hydraulic pressure changes in the whole plant, 3) a stimulus evokes the action potential (AP), and its transmission along the whole plant, plant organ or specialized tissue, by local circuits from cell to cell. Strong, damaging stimuli can evoke variation potentials (VPs), the character of which differs from APs. It is postulated that transmission of VP occurs by a hydraulic dispersion and electrical changes seem to be secondary phenomena.
6

Changes of electric potential in pistils of Petunia hybrida Hort. and Brassica napus L. during pollination

75%
Wedzony M., Filek M.
Acta Physiologiae Plantarum
|
1998
|
tom 20
|
nr 3
The pattern of electric signals accompanying compatible and incompatible pollination were studied in pistils of petunia (Petunia hybrida L.) and rape (Brassica napus L). Electric potential was recorded for 4–7 hours with non-polarizable Ag/AgCl electrodes implanted into the ovary and beneath the sigma. At the end of measurements, pistils were fixed and the growth of pollen tubes was analyzed under a fluorescent microscope. Action potentials appeared in both species. In rape the potential dropped by 10 mV for few minutes after pollination regardless of the compatibility of the cross. In this species, during compatible pollination action potentials with amplitudes of 15–20 mV were recorded up to one hour after pollination. They were followed by a long lasting decrease of the potential by 10 to 50 mV. Contrary, after the self-incompatible pollination, action potentials were rare and of lower amplitudes and the potential gradually raised in comparison to the initial level. During the first hour after the compatible pollination of Petunia hybrida series of action potentials with amplitudes reaching 10–20 mV were recorded. At the time corresponding to the pollen tubes entrance to the transmitting tissue of the style, action potentials reaching up to 40 mV were followed by a steady decrease of the potential. The electric signals traveled along the style with velocity of 25 mm/s. Incompatible pollination in petunia resulted only in minor oscillation and gradual increase of the potential up to 100 mV in comparison to the initial level. The present investigation demonstrated that each phase of pollen-stigma recognition events, germination and growth of pollen tubes within the style have its characteristic pattern of electric changes which was species specific and depended on compatibility of the cross.
7

Linking extracellular electric potential in the brain to neural activity - a review of source localization and component identification methods

63%
Leski S.
Acta Neurobiologiae Experimentalis
|
2015
|
tom 75
|
nr 2
Due to technological advances in electrophysiology, there is renewed interest in the analysis of local field potentials recorded at many sites simultaneously. In this paper the main problems related to the analysis of LFP are presented, and recent developments in the data analysis methods are reviewed. The focus of the paper is on reconstruction of current source density from extracellular recordings and on decomposition of neural activity into meaningful components.
8

The electrical potential difference through the foot epithelium of the snail Achatina achatina, Lameere during mechanical and chemical stimulation

63%
Tyrakowski T., Holynska I., Lampka M., Kaczorowski P.
Folia Biologica
|
2006
|
tom 54
|
nr 3-4
9

Induced by pollination changes of electric potential in pistils of Petunia hybrida L. and Brassica napus L.

63%
Wedzony M., Filek M.
Acta Biologica Cracoviensia. Series Botanica et Zoologia. Supplement
|
1997
|
tom 39
|
nr 1
10

Effect of growth at low temperature on the alternative pathway respiration in Acanthamoeba castellanii mitochondria

51%
Jarmuszkiewicz W., Fraczyk O., Hryniewiecka L.
Acta Biochimica Polonica
|
2001
|
tom 48
|
nr 3
Mitochondria of amoeba Acanthamoeba castellanii in addition to the conventional cytochrome pathway possess, like plant mitochondria, a cyanide-resistant alternative quinol oxidase. In mitochondria isolated from amoeba batch culture grown tempo­rarily at low temperature (6°C), higher respiration was accompanied by lower cou­pling parameters as compared to control culture (grown at 28°C). In the presence of benzohydroxamate, respiratory rates and coupling parameters were similar in both types of mitochondria indicating that growth in cold conditions did not disturb the cytochrome pathway. Increased contribution of alternative oxidase in total mitochon­drial respiration in low-temperature-grown amoeba cells was confirmed by calcula­tion of its contribution using ADP/O measurements. Furthermore, in mitochondria from low-temperature- grown cells the content of the alternative oxidase was in­creased and correlated with the increase in the unstimulated and GMP-stimulated cya­nide-resistant respiratory activity. A possible physiological role of higher activity of alternative oxidase as response to growth at a low temperature in unicellular organ­isms, such as amoeba, is discussed.
11

Determining dispersion of selected mountain soils using electrical potential differences in a system of conjugated LTCC electrodes

51%
Wozniczka P., Chodak T., Golonka L., Zawada T., Roguszczak H.
Polish Journal of Soil Science
|
2006
|
tom 39
|
nr 2
The phenomena of colloid coagulation and peptization have a significant role in the circulation of elements in the surface layer of lithosphere, and in particular in the soil environment. Thanks to their structural properties, the mineral, mineral-organic and organic colloids that occur in colloidal systems largely influence the entire processes leading to erosion. The majority of issues related to the intensification of migration soil colloids and ions in the lithosphere are related to their electrokinetic properties. An attempt has been made in this paper to determine the dispersion state of soil colloidal systems exposed to water erosion by measuring the difference of electrical potentials generated in the gravimetric sedimentation process of colloidal particles. Preliminary results make it plausible to claim that, depending on the quantity and quality of ions in soil solutions and on the qualitative and quantitative composition of colloids, the potential difference determined using measurement electrodes is proportional to the electrokinetic potential of the particles. Such measurements can be carried out in the field. The suggested method is based on recording the difference in potentials with a conjugated measurement electrode, which enables determination of the state of soil colloidal dispersion in the biochemical processes, which occur in the surface layers of the lithosphere.
12

Wpływ jonów kadmu na reakcję fotoelektryczną komórek Nitellopsis obtusa

45%
Stolarek J., Kurtyka R., Karcz W., Mroczkowska-Badner E., Malkowski E.
Acta Biologica Silesiana
|
1991
|
tom 17
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