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1

Effect of divalent metal ions on annexin-mediated aggregation of asolectin liposomes.

100%

Mel'gunov V. I., Akimova E. I., Krasavchenko K. S.

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2000

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vol. 47

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issue 3

675-683

EN

Annexins belong to a family of Ca2+- and phospholipid-binding proteins that can mediate the aggregation of granules and vesicles in the presence of Ca2+. We have studied the effects of different divalent metal ions on annexin-mediated aggregation of liposomes using annexins isolated from rabbit liver and large unilamellar vesicles prepared from soybean asolectin II-S. In the course of these studies, we have found that annexin-mediated aggregation of liposomes can be driven by various earth and transition metal ions other than Ca2+. The ability of metal ions to induce annexin-mediated aggregation decreases in the order: Cd2+>Ba2+, Sr2+>Ca2+>>Mn2+>Ni2+>>Co2+. Annexin-mediated aggregation of vesicles is more selective to metal ions than the binding of annexins to membranes. We speculate that not every type of divalent metal ion can induce conformational change sufficient to promote the interaction of annexins either with two opposing membranes or with opposing protein molecules. Relative concentration ratios of metal ions in the intimate environment may be crucial for the functioning of annexins within specialized tissues and after treatment with toxic metal ions.

2

Generation of stable, non-aggregating Saccharomyces cerevisiae wild isolates

100%

Wloch-Salamon D., Plech M., Majewska J.

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2013

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vol. 60

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issue 4

657-660

EN

Cellular aggregates observed during growth of Saccharomyces cerevisiae strains derived from various natural environments makes most laboratory techniques optimized for non-aggregating laboratory strains inappropriate. We describe a method to reduce the size and percentage of the aggregates. This is achieved by replacing the native allele of the AMN1 gene with an allele found in the W303 laboratory strain. The reduction in aggregates is consistent across various environments and generations, with no change in maximum population density or strain viability, and only minor changes in maximum growth rate and colony morphology.

3

In vitro effect of pentoxifylline and lisofylline on deformability and aggregation of red blood cells from healthy subjects and patients with chronic venous disease

88%

Słoczyńska K., Kózka M., Pękala E., Marchewka A., Marona H.

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2013

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vol. 60

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issue 1

129-135

EN

Purpose. The aim of the study was to assess the in vitro potency of pentoxifylline (PTX) and one of its most active metabolites lisofylline (LSF) to improve rheological properties of red blood cells (RBC) from healthy individuals and patients with chronic venous disease (CVD). Additionally, the study aimed to compare the effects of PTX and LSF on RBC deformability and aggregation. Methods. Blood samples were collected from healthy volunteers (antecubital vein) and from CVD patients (varicose and antecubital vein). Deformability and aggregation of RBC were assessed using Laser-assisted Optical Rotational Cell Analyser (LORCA). Results. PTX and LSF increased RBC elongation significantly. Additionally, RBC incubation with PTX resulted in a marked decrease in RBC aggregation. PTX reduced the tendency towards the formation of RBC aggregates and of their stability. The beneficial effect of PTX on RBC aggregation was most apparent for those cells whose aggregation tendency and aggregate stability was the greatest. Conclusions. In vitro addition of PTX or LSF effectively increased deformability of RBC from healthy donors and patients with CVD. Thus, LSF may contribute to the in vivo hemorheological effects of pentoxifylline. On the other hand, there was no significant effect of LSF on aggregation of RBC in vitro. Hence, LSF has no contribution to this particular effect of PTX. Additionally, the present study demonstrated the use of RBC with impaired deformability and aggregation for the evaluation of in vitro rheological activity of xenobiotics.

4

Flocculation of flotation tailings using thermosensitive polymers

88%

Bogacz W., Lemanowicz M., Gierczycki A., Mielańczyk A.

Chemical and Process Engineering

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2017

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vol. 38

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issue 3

5

Peroxynitrite can affect platelet responses by inhibiting energy production

75%

Rusak T., Tomasiak M., Ciborowski M.

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2006

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vol. 53

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issue 4

769-776

EN

Peroxynitrite (ONOO-) strongly inhibits agonist-induced platelet responses. However, the mechanisms involved are not completely defined. Using porcine platelets, we tested the hypothesis that ONOO- reduces platelet aggregation and dense granule secretion by inhibiting energy production. It was found that ONOO- (25-300 µM) inhibited collagen-induced dense granule secretion (IC50 = 55 ± 7 µM) more strongly than aggregation (IC50 = 124 ± 16 µM). The antiaggregatory and antisecretory effects of ONOO- were only slightly (5-10%) reduced by 1H-[1,2,4]-oxadiazolo-[4,3-α]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase. In resting platelets ONOO- (50-300 µM) enhanced glycolysis rate and reduced oxygen consumption, in a dose dependent manner. The ONOO- effects on glycolysis rate and oxygen consumption were not abolished by ODQ. The extent of glycolysis stimulation exerted by ONOO- was similar to that produced by respiratory chain inhibitors (cyanide and antimycin A) or an uncoupler (2,4-dinitrophenol). Stimulation of platelets by collagen was associated with a rise in mitochondrial oxygen consumption, accelerated lactate production, and unchanged intracellular ATP content. In contrast to resting cells, in collagen-stimulated platelets, ONOO- (200 µM) distinctly decreased the cellular ATP content. The glycolytic activity and oxygen consumption of resting platelets were not affected by 8-bromoguanosine 3',5'-cyclic monophosphate. Blocking of the mitochondrial ATP production by antimycin A slightly reduced collagen-induced aggregation and strongly inhibited dense granule secretion. Treatment of platelets with ONOO- (50-300 µM) resulted in decreased activities of NADH : ubiquinone oxidoreductase, succinate dehydrogenase and cytochrome oxidase. It is concluded that the inhibitory effect of ONOO- on platelet secretion and to a lesser extent on aggregation may be mediated, at least in part, by the reduction of mitochondrial energy production.

6

Superlative carotenoids

63%

Sliwka H.-R., Partali V.

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2012

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vol. 59

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issue 1

17-20

EN

A selection of carotenoids beyond normal appearance or properties has been presented at the 16th International Symposium on Carotenoids. Some of the exceptional compounds shown at the conference cannot be reproduced in this proceeding since they have not yet been published. In addition, editorial space limitation does not allow illustrating all of the previously mentioned carotenoids.

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5 Acta Biochimica Polonica

1 Chemical and Process Engineering

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1 Akimova E. I.

1 Bogacz W.

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1 Gierczycki A.

1 Krasavchenko K. S.

1 Kózka M.

1 Lemanowicz M.

1 Majewska J.

1 Marchewka A.

1 Marona H.

1 Mel'gunov V. I.

1 Mielańczyk A.

1 Partali V.

1 Plech M.

1 Pękala E.

1 Rusak T.

1 Sliwka H.-R.

1 Słoczyńska K.