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1.

001-es BibID:BIBFORM006034
Első szerző:Gáspár Rezső (biofizikus)
Cím:Bretylium-induced voltage-gated sodium current in human lymphocytes / Rezső Gáspár, Zoltán Krasznai, Teréz Márián, Lajos Trón, Rina Recchioni, Marco Falasca, Fausto Moroni, Carlo Pieri, Sándor Damjanovich
Dátum:1992
ISSN:0167-4889
Megjegyzések:Using the whole-cell variation of the patch-clamp technique it has been determined that 0.25-3 mM bretylium tosylate (BT) exerts a repolarizing effect on partially depolarized human lymphocytes. The repolarizing effect was ouabain (40 microM)-sensitive, and was inhibited by the removal of external Na+ or by the Na(+)-channel-blocker amiloride (10-44 microM), but K(+)-channel-blockers 4-aminopyridine (0.1-5 mM) and quinine (100 microM) had no effect. The drug induced a sodium dependent, amiloride-sensitive transient inward current reaching its maximum value approx. 20-30 s after the administration of BT and lasting for 6-10 min. This current was activated by depolarization within 25 ms at around -42 mV, its inactivation took about 2 s and its reversal potential was +24 +/- 5 mV. An increase in the intracellular sodium concentration (1.8-3.2 mM) has been observed upon the addition of BT by monitoring the SBFI fluorescence of the dye-loaded cells. It has been shown that whole-cell K+ currents are significantly decreased by BT. The existence of voltage and ligand (BT)-gated sodium channels has been postulated in human lymphocytes. These channels are thought to participate in the initiation of membrane repolarization in human lymphocytes, and thereby influence mitogenic or antigen-induced cell-activation processes.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Bretylium
Ion channel
Patch-clamp
Human lymphocyte
Megjelenés:Biochimica et Biophysica Acta (BBA). Molecular Cell Research. - 1137 : 2 (1992), p. 143-147. -
További szerzők:Krasznai Zoltán (1950-) (biofizikus) Márián Teréz (1950-) (radiobiológus) Trón Lajos (1941-) (biofizikus) Recchioni, Rina Falasca, Marco Moroni, Fausto Pieri, Carlo Damjanovich Sándor (1936-2017) (biofizikus)
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2.

001-es BibID:BIBFORM006046
Első szerző:Mátyus László (biofizikus)
Cím:Voltage gating of Ca2(+)-activated potassium channels in human lymphocytes / Matyus, L., Pieri, C., Recchioni, R., Moroni, F., Bene, L., Tron, L., Damjanovich, S.
Dátum:1990
Megjegyzések:The effect of membrane potential on Ca2+ activated K+ channels was studied on human peripheral lymphocytes. Membrane potential was monitored using bisoxonol and flow cytometry. 1 mM Ca2+ in the presence of 2 microM ionomycin depolarized the control cell population, while 100 microM Ca2+ caused hyperpolarization. However 1 mM Ca2+ had a hyperpolarizing effect on previously partially depolarized cells. Potassium channel blockers did not influence the depolarization, while they inhibited the hyperpolarization. Based on the experimental evidence a voltage gating of Ca2+ activated K+ channels is suggested.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Biophysics
Calcium
drug effects
Flow Cytometry
Human
Hungary
In Vitro
Ion Channel Gating
Ionomycin
Leukocytes,Mononuclear
Lymphocytes
Membrane Potentials
pharmacology
physiology
Potassium
Potassium Channel Blockers
Potassium Channels
Support,Non-U.S.Gov't
Megjelenés:Biochemical and Biophysical Research Communications. - 171 : 1 (1990), p. 325-329. -
További szerzők:Pieri, Carlo Recchioni, Rina Moroni, Fausto Bene László (1963-) (biofizikus) Trón Lajos (1941-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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DOI
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3.

001-es BibID:BIBFORM043991
Első szerző:Pieri, Carlo
Cím:Bretylium differentiates between distinct signal transducing pathways in human lymphocytes / Pieri, C., Bacso, Z., Recchioni, R., Moroni, F., Balazs, M., Gaspar, R., Damjanovich, S.
Dátum:1993
ISSN:0006-291X
Megjegyzések:The selection of signal transducing pathways of T cells depends on the type of triggers. Antigens, antibodies or lectins induce the T cell receptor-CD3 operated pathway, and IL-2 transmits its activation signal via the IL-2 receptor. It has been demonstrated that bretylium, a quaternary ammonium ion, can significantly inhibit the first pathway at the same dose range that stimulates cell activation through the IL-2 receptor system. In the light of the different complexity of the two pathways at the plasma membrane level, and the non-toxic and reversible behavior of the drug, it is suggested that the bretylium induced sustained membrane hyperpolarization is responsible for the observation. This finding may open new possibilities in studying the mechanism of different signal transducing pathways.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Biochemical And Biophysical Research Communications. - 190 : 2 (1993), p. 654-659. -
További szerzők:Bacsó Zsolt (1963-) (biofizikus) Recchioni, Rina Moroni, Fausto Balázs Margit (1952-) (sejtbiológus, molekuláris genetikus) Gáspár Rezső (1944-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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DOI
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4.

001-es BibID:BIBFORM006051
Első szerző:Pieri, Carlo
Cím:The response of human lymphocytes to phytohemagglutinin is impaired at different levels during aging / Pieri, C., Recchioni, R., Moroni, F., Marcheselli, F., Damjanovich, S.
Dátum:1992
Megjegyzések:Several parameters generally believed to be necessary for the activation and progression of proliferation of human lymphocytes have been investigated and compared with special reference to aging. The responding capacity of plasma membrane potential to depolarizing and also repolarizing conditions induced by exposure to mitogens like PHA was lower in lymphocytes from old donors as compared to those of young ones. This indicates a significant age-dependent difference in the readiness to respond to channel-activating perturbations. As an early signal of activation, after one hour PHA stimulation the merocyanine 540 uptake by the lipid regions was chosen, based on the property of this fluorescent probe to bind to loosely packed lipids of the plasma membrane. The proteins encoded by the c-myc and c-myb genes were chosen as markers of the G0/G1 and G1/S phased transition, respectively. The mean number of cells that increased the uptake of MC 540 following mitogenic stimulation did not differ in young vs. old individuals. However, 4 samples out of 10 from the old population showed lower MC 540 fluorescence than the lowest signal from the young population. The number of responding cells was decreased during aging when the presence of the c-myc protein was taken as its measure; and this decrease was further accentuated, determining the expression of the c-myb protein. This frequently encountered age-dependent pattern, however, was not followed by the lymphocytes of all old donors. One example is reported in which the MC 540 uptake, the c-myc and c-myb expression in the cells from one old subject fell in the range of the young subjects. However, even in this case, the response of the lymphocytes as measured by 3H-thymidine incorporation was only 64% of that of young subjects. For this sample, we found an impairment of the response at the mitochondrial level. In addition to these parameters, the amount of 3H-thymidine incorporated by the cells expressing the c-myb protein was calculated. The values in old individuals were lower than those in the young, suggesting that not all the cells expressing the c-myb protein were able to synthesize DNA in lymphocyte populations from the elderly. Our data support the view that the age-dependent decline of lymphocyte responsiveness to mitogens can be accounted for by impairments at different levels.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Aging
Cell Membrane
Dna
DNA-Binding Proteins
drug effects
Fluorescence
Genome
Human
Lymphocytes
Membrane Potentials
metabolism
pharmacology
physiology
Phytohemagglutinins
Proto-Oncogene Proteins
Proto-Oncogene Proteins c-myb
Proto-Oncogene Proteins c-myc
Research
Support,Non-U.S.Gov't
Thymidine
Megjelenés:Annals of the New York Academy of Sciences. - 673 (1992), p. 110-119. -
További szerzők:Recchioni, Rina Moroni, Fausto Marcheselli, Fiorella Damjanovich Sándor (1936-2017) (biofizikus)
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5.

001-es BibID:BIBFORM006052
Első szerző:Pieri, Carlo
Cím:A sodium channel opener inhibits stimulation of human peripheral blood mononuclear cells / Pieri, C., Recchioni, R., Moroni, F., Marcheselli, F., Falasca, M., Krasznai, Z., Gaspar, R., Matyus, L., Damjanovich, S.
Dátum:1992
Megjegyzések:The role of membrane potential changes in T cell activation was studied on human peripheral blood lymphocytes stimulated with phytohemagglutinin. Addition of bretylium tosylate, a sodium channels opener, to PHA treated lymphocytes modified the membrane potential and consequently blocked cell activation in a dose-dependent fashion. BT was non-toxic even in long-term (72 hr) incubations. It was reversibly removable, and the removal restored the stimulatory effect of PHA. 3H-thymidine incorporation was blocked if BT was present during the first 20-24 hr of the mitogenic activation. The later BT was added after PHA, the less inhibition of proliferation was observed. BT hyperpolarized the lymphocytes also in the presence of PHA. BT hindered the depolarizing effect of high extracellular potassium concns. The sustained polarized state of the lymphocytes did not influence the intracellular calcium increase upon PHA treatment. IL-2 and transferrin receptor expression was not hindered by BT during PHA stimulation of lymphocytes. Addition of rIL-2 did not abolish the inhibitory effect of BT. According to cell-cycle analysis BT arrested the majority of the cells in G1 phase. It is suggested that cell activation demands the flexible maintenance of a relatively narrow membrane potential "window". Any sustained and significant hyper-, or depolarization, may dramatically decrease the effectivity of transmembrane signalling.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
analysis
blood
Bretylium Tosylate
Calcium
Cell Cycle
cytology
Dose-Response Relationship,Drug
drug effects
Flow Cytometry
Human
In Vitro
Interleukin-2
Lymphocyte Transformation
Lymphocytes
Membrane Potentials
pharmacology
physiology
Phytohemagglutinins
Potassium
Receptors,Transferrin
Research
Sodium
Sodium Channels
Support,Non-U.S.Gov't
T-Lymphocytes
Megjelenés:Molecular Immunology. - 29 : 4 (1992), p. 517-524. -
További szerzők:Recchioni, Rina Moroni, Fausto Marcheselli, Fiorella Falasca, Marco Krasznai Zoltán (1950-) (biofizikus) Gáspár Rezső (1944-) (biofizikus) Mátyus László (1956-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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6.

001-es BibID:BIBFORM005987
Első szerző:Pieri, Carlo
Cím:Ligand and voltage gated sodium channels may regulate electrogenic pump activity in human, mouse and rat lymphocytes / C. Pieri, R. Recchioni, F. Moroni, L. Balkay, T. Márián, L. Trón, S. Damjanovich
Dátum:1989
Megjegyzések:Bretylium tosylate - a sodium channel opener - resulted in an increase of membrane potential of depolarized human, rat and mouse T and B lymphocytes. Flow cytometric membrane potential measurements with bis-oxonol revealed that the above hyperpolarizing effect was amiloride, ouabain, tetrodotoxin, azide and temperature sensitive. The effect showed an absolute dependence on the extracellular sodium but it was insensitive to the extracellular Ca2+ level. The voltage gating of the effect can be eliminated by either an increase of the extracellular potassium concentration or low doses of veratrin. The existence of a voltage and ligand gated sodium channel is suggested in the plasma membrane of all kinds of lymphocytes. The hyperpolarization is explained by an increased activity of the electrogenic sodium-potassium ATP-ase. Induced opening of such sodium channels may regulate the electrogenic pump activity and indirectly cell activation.
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
Amiloride
Animal
B-Lymphocytes
Bretylium Tosylate
Calcium
Cell Membrane
drug effects
Dyes
Electrochemistry
Female
Flow Cytometry
Fluorescent Dyes
Human
Lymphocytes
Membrane Potentials
Mice
Mice,Inbred BALB C
Mice,Nude
pharmacology
physiology
Potassium
Rats
Sodium
Sodium Channels
Support,Non-U.S.Gov't
Tetrodotoxin
Thiobarbiturates
Megjelenés:Biochemical and Biophysical Research Communications. - 160 : 3 (1989), p. 999-1002. -
További szerzők:Recchioni, Rina Moroni, Fausto Balkay László (1963-) (biofizikus) Márián Teréz (1950-) (radiobiológus) Trón Lajos (1941-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus)
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7.

001-es BibID:BIBFORM004637
Első szerző:Recchioni, Rina
Cím:Melatonin increases the intensity of respiratory burst and prevents L-selectin shedding in human neutrophils in vitro / Recchioni, R., Marcheselli, F., Moroni, F., Gaspar, R., Damjanovich, S., Pieri, C.
Dátum:1998
ISSN:006-291X
Megjegyzések:Effects of melatonin priming of neutrophils and subsequent increase of phorbol 12-miristate 13-acetate stimulated respiratory burst were investigated on the modulation of L-selectin shedding and MAC-1 upregulation. Respiratory burst related H2O2 production and adhesion molecule expression were quantified by flow cytometry. Phorbol 12-miristate 13-acetate dose dependence of intracellular oxidation and adhesion molecule expression showed no relationship between respiratory burst intensity and MAC-1 expression or L-selectin shedding. Treatment of cells with 12.5 nM phorbol 12-miristate 13-acetate resulted in less than 20% of the respiratory burst response, however it induced 91.7% of total MAC-1 expression and 62.8% of L-selectin shedding. Melatonin priming experiments showed also no connection between the extent of respiratory burst and MAC-1 expression, however melatonin priming almost completely prevented L-selectin down-regulation elicited by phorbol 12-miristate 13-acetate, without affecting MAC-1 expression. It is suggested that melatonin may inhibit metalloproteases responsible for L-selectin cleavage
Tárgyszavak:Orvostudományok Elméleti orvostudományok idegen nyelvű folyóiratközlemény külföldi lapban
biosynthesis
blood
Dose-Response Relationship,Drug
drug effects
Flow Cytometry
Human
Hydrogen Peroxide
In Vitro
Kinetics
L-Selectin
Macrophage-1 Antigen
Melatonin
Neutrophils
pharmacology
physiology
Research
Respiratory Burst
Rhodamine 123
Support, Non-U.S.Gov't
Tetradecanoylphorbol Acetate
Megjelenés:Biochemical and Biophysical Research Communications. - 252 : 1 (1998), p. 20-24. -
További szerzők:Marcheselli, Fiorella Moroni, Fausto Gáspár Rezső (1944-) (biofizikus) Damjanovich Sándor (1936-2017) (biofizikus) Pieri, Carlo
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elektronikus változat
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