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1

A moze by tak kukurydza?

100%
Luczynski J.
INO. Informacje, Nowości, Oferty. Ośrodek Doradztwa Rolniczego w Płocku
|
1995
|
nr 12
10-11
2

Free radicals scavenging by amine N-oxides

51%
Krasowska A., Mroz A., Luczynski J., Piasecki A.
Acta Biochimica Polonica
|
2003
|
tom 50
|
nr Supplement 1
3

Comparative studies of the biological activities of lysosomotropic aminoesters and quaternary ammonium salts on the yeast Saccharomyces cerevisiae

51%
Oblak E., Lachowicz T. M., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 4
871-880
4

Lysosomotropic N,N- dimethyl alpha-aminoacid n-alkyl esters and their quaternary ammonium salts as plasma membrane and mitochondrial ATPases inhibitors

51%
Oblak E., Lachowicz T. M., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr 4
A set of n-alkyl esters of N,N-dimethylglycine (DMG-n) and their methobromides (DMGM-n) was synthesized, and their activities on yeast Saccharomyces cerevisiae were compared. The compounds differ in the number of carbon atoms in the aliphatic chain. Aminoesters with 12 carbon atoms appeared to be most active. Unlike quaternary ammonium salts previously tested, the activities of the compounds were not pH-dependent; the minimal inhibitory concentrations (MIC) were identical at pH 8 and at pH 6. In contrast to quaternary ammonium salts, aminoesters showed similar effects on respiratory sufficient (rho+) and respiratory deficient (rho°) mutants. When tested on glucose stimulated proton extrusion, aminoesters applied at MIC increased external pH. Aminoesters inhibited the plasma membrane H+-ATPase, whereas they were less inhibitory on the mitochondrial ATPase. In order to further compare the aminoesters and their corresponding quaternary ammonium salts, derivatives of N,N-dimethylalanine (DMAL-n and DMALM-n, respectively) were synthesized. The quaternary ammonium salts appeared to have a higher inhibitory potency than aminoesters, especially at pH 8, and alanine derivatives inhibited growth at a lower concentration than glycine derivatives. Both alanine derivatives of the aminoester and the quaternary ammonium salt inhibited the plasma membrane H+- ATPase at lower concentrations than glycine derivatives, but the alanine aminoester was without a detectable effect on the mitochondrial ATPase.
5

The interaction of some lysosomotropic substances with erythrocyte membranes

51%
Kleszczewska H., Bonarska D., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2A
400
6

The aminoesters as inhibitors of plasma membrane H - ATPase in the yeast Saccharomyces cerevisiae

51%
Oblak E., Lachowicz T. M., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2004
|
tom 09
|
nr 4A
755-763
7

Effect of some lysosomotropic substances on erythrocyte membrane

51%
Kleszczynska H., Luczynski J., Witek S., Przestalski S.
Polish Journal of Environmental Studies
|
1997
|
tom 06
|
nr 6
The effect of N,N-dimethylaminoethyl esters of fatty acids (DM n) on pig red blood cell hemolysis and erythrocyte membrane fluidity has been investigated. In the hemolytic experiments the hemolytic activity of the compounds studied was determined, and was found to increase with alkyl chain length and followed the sequence: DM-15 > DM-13 > DM-11 > DMDA > DM-9. The fluorimetric studies were done using the fluorescent probe TMA-DPH, which allowed us to calculate polarization coefficient P and hence determine relative changes in membrane fluidity induced by the lysosomotropic substances. The compounds of highest hemolytic activity, which have fifteen- and thirteen-carbon-atom alkyl chain (DM-15 and DM-13), significantly affect the erythrocyte membrane fluidity.
8

Gemini ester quat surfactants and their biological activity

45%
Luczynski J., Frackowiak R., Wloch A., Kleszczynska H., Witek S.
Cellular and Molecular Biology Letters
|
2013
|
tom 18
|
nr 1
Cationic gemini surfactants are an important class of surface-active compounds that exhibit much higher surface activity than their monomeric counterparts. This type of compound architecture lends itself to the compound being easily adsorbed at interfaces and interacting with the cellular membranes of microorganisms. Conventional cationic surfactants have high chemical stability but poor chemical and biological degradability. One of the main approaches to the design of readily biodegradable and environmentally friendly surfactants involves inserting a bond with limited stability into the surfactant molecule to give a cleavable surfactant. The best-known example of such a compound is the family of ester quats, which are cationic surfactants with a labile ester bond inserted into the molecule. As part of this study, a series of gemini ester quat surfactants were synthesized and assayed for their biological activity. Their hemolytic activity and changes in the fluidity and packing order of the lipid polar heads were used as the measures of their biological activity. A clear correlation between the hemolytic activity of the tested compounds and their alkyl chain length was established. It was found that the compounds with a long hydrocarbon chain showed higher activity. Moreover, the compounds with greater spacing between their alkyl chains were more active. This proves that they incorporate more easily into the lipid bilayer of the erythrocyte membrane and affect its properties to a greater extent. A better understanding of the process of cell lysis by surfactants and of their biological activity may assist in developing surfactants with enhanced selectivity and in widening their range of application.
9

Quaternary ammonium salts and their corresponding amines as growth inhibitors of baker's yeast Saccharomyces cerevisiae

45%
Oblak E., Lachowicz T. M., Bartosik S., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2A
415
10

Antifungal activity of some model Soft lysosomotropic compounds

45%
Bien M., Lachowicz T. M., Sauter E., Luczynski J., Witek S.
Bulletin of the Polish Academy of Sciences. Biological Sciences
|
1995
|
tom 43
|
nr 2
11

Assessment of biological activity of new compounds designated to act as lysosomotropes

45%
Kleszczynska H., Bonarska D., Luczynski J., Witek S., Sarapuk J.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 6
This work contains the results of studies on the influence of new lysosomotropic substances on an erythrocyte membrane. The compounds studied were hydrochlorides of N,N-dimethylglycine alkyl esters (DMG-n) and N,N-dimethylalanine alkyl esters (DMAL-n) having two different-length alkyl chains (n = 12 and 16), oxalates of dimethylaminoalaninates (DMALs -n; n = 8, 10, 12, 14 and 16) and methobromides of glycinates and alaninates (DMALM-12 and DMGM-12). They were found to hemolyze erythrocytes, to change their osmotic resistance and to influence erythrocyte membrane fluidity. The results obtained indicate that observed changes were dependent on lipophilicities of the compounds. It was especially evident in the case of hemolytic efficiencies of the homologous series of alanine oxalates. Also, DMG-n and DMAL-n compounds significantly differed in their hemolytic properties. Again, slightly better hemolytic efficiency of DMG compounds in comparison with corresponding compounds having the same alkyl chain, DMAL, confirm such a conclusion. However, their hemolytic efficiencies were found to be moderate, which makes them potentially useful membrane modifiers. That feature is important for lysosomotropic compounds and its confirmation was the primary aim of the presented work. It is worth mentioning that DMGM and DMALM compounds exhibited better hemolytic efficiencies than all other compounds studied – which is probably caused by the fact that they were used as bromides. Bromides are commonly found to be more active than compounds with other counterions.
12

The dual mechanism of the antifungal effect of new lysosomotropic agents on the Saccharomyces cerevisiae RXII strain

45%
Krasowska A., Chmielewska L., Luczynski J., Witek S., Sigler K.
Cellular and Molecular Biology Letters
|
2003
|
tom 08
|
nr 1
Quinacrine was used to visualize the intracellular pH changes in the yeast strain Saccharomyces cerevisiae RXII occurring after exposure to four recently-synthesized lysosomotropic drugs: DM-11, PY-11, PYG-12s and DMAL-12s. The cells took up quinacrine, mostly accumulating it in their vacuoles. DM-11 and PY-11 gave rise to diffuse quinacrine fluorescence throughout the cells, with the vacuoles staining to a somewhat greater extent than the cytosol. This quinacrine-detected overall acidification of the cell interior is very probably caused by blocking of plasma membrane H+-ATPase. PYG-12s gave rise to a strong vacuolar accumulation of the dye. Like the vacuolar ATPase inhibitor bafilomycin A1, DMAL-12s strongly lowered the intensity of quinacrine fluorescence. Owing to its low pKa, it can penetrate rapidly into the cells and may inhibit vacuolar H+-ATPase and prevent quinacrine-detectable vacuolar acidification without causing strong cell acidification. Since these drugs were found to penetrate into the cells, their lack of effect may reflect a higher resistance of both plasma membrane H+-ATPase and vacuolar ATPase to the drugs. Our data indicate that the lysosomotropic drugs under study have a dual action. On entering the cell, they cause intracellular acidification, very probably by inhibiting plasma membrane H+-ATPase and curtailing active proton pumping from the cells. Furthermore, they interfere with the function of V-type ATPase, causing vacuolar alkalinization and eventually cell death.
13

The dual mechanism of the antifungal effect of new lysosomotropic agents on yeast and yeast-like cells

45%
Krasowska A., Chmielewska L., Luczynski J., Witek S., Sigler K.
Cellular and Molecular Biology Letters
|
2002
|
tom 07
|
nr Suppl.
14

The antifungal activity of DMAL and PYG class lysosomotropic drugs resultated from their effect on cell membranes

39%
Krasowska A., Chmielewska L., Skala J., Sigler K., Luczynski J., Witek S.
Cellular and Molecular Biology Letters
|
2001
|
tom 06
|
nr 2A
404
15

The sensitivity of yeast and yeast-like cells to new lysosomotropic agents

39%
Krasowska A., Chmielewska L., Adamski R., Luczynski J., Witek S., Sigler K.
Cellular and Molecular Biology Letters
|
2004
|
tom 09
|
nr 4A
675-683
The lysosomotropic action of the compounds DM-11 and DMAL-12s against Saccharomyces cerevisiae, Schizosaccharomyces pombe and Candida albicans is species- and pH-dependent. At pH 6.0, DMAL-12s is less effective against S. cerevisiae and S. pombe but more effective against C. albicans than DM-11. At pH 8.0, DMAL-12s strongly inhibits the growth of S. cerevisiae but has only a marginal effect on the resistant C. albicans. S. pombe did not grow at pH 8.0. As shown by quinacrine accumulation, DM-11 causes a general intracellular acidification in all three species, while with DMAL-12s, the acidification is marginal. Morphological changes caused by DMAL-12s in S. cerevisiae affect the cell interior but not surface structures, while S. pombe cells exhibit a thickened and wrinkled cell wall, shrunken protoplast and "grainy" plasma membrane. A large number of blisters resembling lipid droplets were observed inside S. cerevisiae and S. pombe vacuoles. The high susceptibility of S. pombe cells to the action of DM-11 and DMAL-12s contrasts with the low sensitivity of S. pombe H+-ATPase to the agents. In our C. albicans isolate, DMAL 12s did not have an effect on cell morphology and appeared to be unable to penetrate the cells, especially at pH 8.0.
16

Antioxidative activity of some N-oxides

39%
Kleszczynska H., Bonarska D., Pruchnik H., Bielecki K., Luczynski J., Trela Z., Sarapuk J.
Cellular and Molecular Biology Letters
|
2005
|
tom 10
|
nr Suppl.
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