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1

Effect of bivalent Zn and Cd ions on apoptosis in leyding cells, related to ethylenedimethylsulphate [EDS]

100%
Jankowska A., Skonieczna D., Jaroszewski J., Rommerts F. F. G.
Biological Bulletin of Poznań. Supplement
|
1996
|
tom 33
2
Content available remote

The modulatory effect of zinc ions on voltage-gated potassium currents in cultured rat hippocampal neurons is not related to Kv1.3 channels

86%
Teisseyre T., Mercik K., Mozrzymas J. W.
Journal of Physiology and Pharmacology
|
2007
|
tom 58
|
nr 4
We applied the whole-cell patch-clamp technique to study the influence of zinc ions (Zn2+) and extracellular protons at acidic pH (pHo) on voltage-gated potassium currents in cultured rat hippocampal neurons. The first goal of the study was to estimate whether Kv1.3 currents significantly contributed to voltage-gated potassium currents in examined cells. Then, the influence of both ions on the activity of other voltage-gated potassium currents in the neurons was examined. We examined both the total current and the delayed - rectifier component. Results obtained in both cases were not significantly different from each other. Available data argued against any significant contribution of Kv1.3 currents to the recorded currents. Nevertheless, application of Zn2+ in the concentration range from 100 µM to 5 mM reversibly modulated the recorded currents. The activation midpoint was shifted by about 40 mV (total current) and 30 mV (delayed-rectifier current) towards positive membrane potentials and the activation kinetics were slowed significantly (2 - 3 fold) upon application of Zn2+. The inactivation midpoint was also shifted towards positive membrane potentials, but less significantly (about 14 mV). The current amplitudes were reduced in a concentration-dependent manner to about 0.5 of the control value. The effects of Zn2+ were saturated at the concentration of 1 mM. Raising extracellular proton concentration by lowering the pHo from 7.35 to 6.4 did not affect significantly the currents. Possible mechanisms underlying the observed phenomena and their possible physiological significance are discussed.
3

Platinum ions effect on heavy metals ions in the loessial soil. Part I. Zinc ions

86%
Bojanowska M., Jackowska I.
Ochrona Środowiska i Zasobów Naturalnych
|
1999
|
tom 18
4
Content available remote

Influence of extracellular pH on the modulatory effect of zinc ions on Kv1.3 potassium channels

86%
Teisseyre A., Mozrzymas J. W.
Journal of Physiology and Pharmacology
|
2006
|
tom 57
|
nr 1
In the present study we applied the whole-cell patch-clamp technique to study the influence of extracellular pH (pHo) on the modulatory effect exerted by zinc ions (Zn2+) on voltage-gated potassium channels Kv1.3 expressed in human lymphocytes. Obtained data provide evidence that lowering of pHo from the 7.35 to 6.4 slowed significantly the current activation rate, shifted the activation midpoint by about 16 mV towards positive membrane potentials and reduced the current amplitude to about 0.55 of the control value. In contrast, raising the pHo from 7.35 to 8.4 did not affect significantly the activation midpoint and current amplitude. Application of Zn2+ in the concentration range from 100 µM to 1 mM at pHo=6.4 slowed additionally the activation rate, shifted the activation midpoint by about 20 mV towards positive membrane potentials and reduced the current amplitude in a concentration-dependent manner. The total effect exerted by Zn2+ and protons at pHo = 6.4 was more significant than the effect exerted by Zn alone. Both the magnitude of the shift and the degree of current inhibition by Zn2+ were independent on pHo in the range from 6.4 to 8.4. The data might suggest that the effects exerted by protons and zinc ions occur independently on each other and probably involve different mechanisms. Changing the holding potential from -90 mV to -60 mV at pHo=7.35 abolished the Zn2+-induced inhibition of the current amplitudes at concentrations below 300 µM. At pHo=6.4 the total inhibition caused by Zn2+ and protons was also diminished, however, a significant reduction was observed at 100 µM concentration. In contrast, changing the holding potential did not change the Zn2+- and proton-induced shift of the activation midpoint. Altogether, obtained data suggest that extracellular protons exert the modulatory effects that are additive to the effects exerted by Zn2+ on the channels. Possible physiological significance of these additive effects is discussed.
5
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Effects of glutamate and zinc ions on the contractility of vascular smooth muscle preparations

72%
Nguyen-Duong H.
Journal of Elementology
|
2010
|
tom 15
|
nr 3
559-572
It was shown in this study that isolated porcine coronary arteries (PCA) contracted by depolarization with high Ko or by histamine are dose-dependently relaxed by glutamic acid, aspartic acid, N-methyl-asparate (NMDA) and γ-aminobutyric acid (GABA). Zn2+ was also shown to relax dose-dependently PCA contractions induced by 50 mM KCl with an ED50 value of about 1.5 mM and to inhibit dose-dependently histamine-induced contractions, shifting ED50 values from 6μM to 40 μM, not affecting however corresponding cumulative concentration-response (CCR) curves established for acetylcholine-induced contractions. Furthermore, since Zn2+ ions are co-localized in many glutamatergic synapses of the central nervous system, it has been postulated in analogy to glutamate neurotoxicity that perturbations of the synaptic zinc concentrations might be a triggering factor in several cerebral diseases, such as ischemic strokes and sustained seizures. Unfortunately, little is known so far about effects of glutamate and zinc ions on the vascular tone. Although the nature of the glutamatergic receptors occurring in the blood vessels investigated in this study remains unclear, the results suggest that glutamate and Zn2+ ions interact with voltage-gated as well with ligand-operated Ca-channels. An interesting aspect might be the putative role of glutamate and zinc as long-term toxic agents in the early steps of the pathomechanisms leading to degenerative vascular lesions.
6
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Effect of the addition of zinc and selenium ions on the stability of the Biolasol liquid used for perfusion, reperfusion and preservation of parenchymal organs of the abdominal cavity

72%
Ostrozka-Cieslik A., Dolinska B., Caban A., Ryszka F.
Journal of Elementology
|
2015
|
tom 20
|
nr 2
The Biolasol® liquid is an innovative solution used for perfusion, reperfusion and preservation of parenchymal organs of the abdominal cavity. Substances in the liquid prevent cellular oedema and help to maintain a proper water/mineral as well as acid/base balance in the intracellular environment. They also minimize free-radical injuries and ensure the integrity of the cellular membrane structure. The Biolasol® liquid has been shown to be much more efficient than the HTK liquid in the preservation of kidneys. The Biolasol® liquid containing 0.5 mM of vitamin C has been modified by adding ions of Se(IV), Zn(II), and their effect on the stability of the solution was examined. An accelerated aging test was applied to test the liquid stability. The test, based on the laws of chemical kinetics, was conducted at four temperatures at a 10°C step, that is: 50°C±0.05, 60°C±0.05, 70°C±0.05 and 80°C±0.05. The relative humidity equalled 75% of RH and the duartion of the test was 40 days. In order to determine the stability of the tested solutions, the Arrhenius Dependence equation was used, applied to the effect of temperature on the glucose decomposition reaction rate: lnk=lnA-(Ea/RT). The results indicate that the addition of zinc decreases the stability of the liquid by 30.5%, while the addition of selenium prolongs the stability by 8.21%. This is explained by the synergism of action of vitamin C and Se4+ antioxidant in the tested liquid. Zinc ions present in the solution increase the glucose decomposition reaction rate.
7
Content available remote

Popular species of edible mushrooms as a good source of zinc to be released to artificial digestive juices

72%
Zajac M., Muszynska B., Kala K., Sikora A., Opoka W.
Journal of Physiology and Pharmacology
|
2015
|
tom 66
|
nr 5
8

Sorption of copper and zinc ions by various cereal bran and collagen and elastin preparations

72%
Stachowiak J., Smigielska H.
Acta Scientiarum Polonorum. Technologia Alimentaria
|
2004
|
tom 03
|
nr 1
Sorption of copper and zinc on wheat and rye bran as well as on collagen and elastin preparations under conditions simulating human digestive system parameters was determined. Results collected during this study indicate, that sorption abilities of investigated preparations are differential and depend on the origin source, as well as pH environment. Wheat and rye bran showed higher sorption ability. The value of copper and zinc sorption was between 39-82% and was lower for collagen and elastin (15-17%). Examined preparations show higher sorption ability when pH equals 8.7 and 6.8, and lower value of this parameter in an acidic environment.
9

The effect of mercury [Hg2], copper [Cu2] and zinc [Zn2] ions on bacteria isolated from surface microlayer and subsurface water of the Lake Maly Jeziorak

72%
Donderski W., Gluchowska M., Wodkowska A.
Biological Bulletin of Poznań. Supplement
|
1996
|
tom 33
10

The influence of protons and zinc ions on the steady-state inactivation of Kv1.3 potassium channels

72%
Teisseyre A., Mozrzymas J. W.
Cellular and Molecular Biology Letters
|
2007
|
tom 12
|
nr 2
Using the whole-cell patch-clamp technique, we investigated the influence of extracellular pH and zinc ions (Zn2+) on the steady-state inactivation of Kv1.3 channels expressed in human lymphocytes. The obtained data showed that lowering the extracellular pH from 7.35 to 6.8 shifted the inactivation midpoint (Vi) by 17.4 ± 1.12 mV (n = 6) towards positive membrane potentials. This shift was statistically significant (p < 0.05). Applying 100 μM Zn2+ at pH 6.8 further shifted the Vi value by 16.55 ± 1.80 mV (n = 6) towards positive membrane potentials. This shift was also statistically significant (p < 0.05). The total shift of the Vi by protons and Zn2+ was 33.95 ± 1.90 mV (n = 6), which was significantly higher (p < 0.05) than the shift caused by Zn2+ alone. The Zn2+-induced shift of the Vi at pH 6.8 was almost identical to the shift at pH = 7.35. Thus, the proton-and Zn2+-induced shifts of the Vi value were additive. The steady-state inactivation curves as a function of membrane voltage were compared with the functions of the steady-state activation. The total shift of the steady-state inactivation was almost identical to the total shift of the steady-state activation (32.01 ± 2.10 mV, n = 10). As a result, the “windows” of membrane potentials in which the channels can be active under physiological conditions were also markedly shifted towards positive membrane potentials. The values of membrane voltage and the normalised chord conductance corresponding to the points of intersection of the curves of steady-state activation and inactivation were also calculated. The possible physiological significance of the observed modulatory effects is discussed herein.
11

The effect of copper, zinc and iron ions on induction of the reactive oxygen species production in tobacco by-2 cell suspension culture

72%
Zrobek-Sokolnik A., Gorecki R. J.
Polish Journal of Natural Sciences. Supplement
|
2003
|
tom 01
12

Influence of zinc and lead ions on the course of embryogenesis of Ascaris suum [Nematoda]

72%
Bialowas K., Zoltowska K., Lopienska E.
Acta Biologica Cracoviensia. Series Botanica. Supplement
|
2000
|
tom 42
|
nr 1
13

Effect of calf thymus extract and zinc supplementation on the cellular response of mice exposed to restraint stress

58%
Obminska-Mrukowicz B., Szczypka M.
Polish Journal of Veterinary Sciences
|
2005
|
tom 08
|
nr 1
14

Kumulacja i wydalanie jonow manganu u myszy w obecnosci jonow cynku i egzogennej melaniny

58%
Bogacz A., Bijak A., Buszman E., Wilczok T.
Bromatologia i Chemia Toksykologiczna
|
1995
|
tom 28
|
nr 4
377-382
Przebadano wpływ jonów Zn2+ i egzogennej melaniny na kumulację i szybkość wydalania jonów Mn2+ u myszy Balb c ( nie zawierających endogennej melaniny ) i C-57 Black (zawierających w sierści melaninę).
15

The effects of thymomimetic drugs and zinc supplementation on viability of hydrocortisone-treated mouse thymocytes

58%
Obminska-Domoradzka B., Deboowy J.
Polish Journal of Veterinary Sciences
|
2000
|
tom 03
|
nr 4
The studies in vitro were carried out on isolated thymic cells of Balb/c mice. The thymocyte cultures were incubated with calf thymus extract (TFX) and diethyldithiocarbamate (DTC) at a concentrations of 0.1-100 μg/ml or zinc ions (as sulphate salt) at a concentration of 1 μg/ml, and next the latter culture was supplemented with hydrocortisone at a concentration of 50 μg/ml/culture. The results of the study show that hydrocortisone supplementation decreases the survival rate of cells by approximately 50% in relation to the control. Preincubation of thymocytes with TFX or DTC perse and in zinc interactions increases the percentage of viable thymocytes, as it results in the induction of differentiation and maturation of the cells under investigation. The preventive action of the two drugs against the thymolythic effect of hydrocortisone depends on TFX and DTC concentrations, the presence of zinc ions and length of incubation. A stronger preventive effect against the cytotoxic impact of hydrocortisone has been observed with TFX than with DTC. The effect of steroid resistance of thymocytes induced by the two thymomimetic drugs is enhanced by zinc ions.
16
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Wiazanie jonow metali przez wybrane frakcje substancji zawartych w wytlokach owocow

44%
Nawirska A., Oszmianski J.
Żywność Nauka Technologia Jakość
|
2001
|
tom 08
|
nr 4
66-77
Celem pracy było określenie możliwości wiązania jonów wybranych metali (Cu2+ , Cd2+ , Pb2+ i Zn2+ )z roztworów wodnych przez frakcje zawarte w wytłokach z owoców aronii, gruszek, jabłek i dzikiej róży. Zbadano, w jakim stopniu analizowane frakcje wytłoków (polifenole, pektyny, hemicelulozy, celulozy i ligniny) wiążą jony poszczególnych metali ciężkich. W tym celu pozbawiono wytłoki kolejnych frakcji, a następnie poddano te wytłoki działaniu roztworów metali o stężeniach w zakresie od 4 do 10 g Me/m3. Stężenia jonów metali w roztworze wyjściowym oraz po 30 minutach kontaktu z wytłokami badano w temperaturze pokojowej przy pH w zakresie od 6,2 do 7,0. Następnie uzyskane wyniki przeliczano na 100 g frakcji. Pektyny były frakcją wiążącą największe ilości jonów miedzi, kadmu i cynku, natomiast polifenole wiązały najwięcej jonów ołowiu, wykazując równocześnie odmienne właściwości w porównaniu z pozostałymi frakcjami. Polifenole zawarte w wytłokach z aronii wiązały wszystkie badane jony, natomiast uzyskane z pozostałych wytłoków - jedynie jony ołowiu. Najgorzej wiążącą frakcją uzyskaną z wytłoków były ligniny. Frakcja celulozy była najbardziej zróżnicowana, wiązała jony metali w różnym stopniu, w zależności od tego, z jakiego rodzaju wytłoków była uzyskana. Otrzymane wyniki mogą być przydatne w komponowaniu mieszanek z wytłoków do usuwania jonów metali z roztworów wodnych.
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