Wyniki wyszukiwania

1

Field-theoretical approach to the action potential

100%

Pietruszka M., Stolarek J.

Biophysics of Membrane Transport

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1994

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tom 12

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nr 2

2

Law and order in the nucleus: dynamics of replication factories in living cells

100%

Cardoso M. C., Rahn H. P., Sporbert A., Leonhardt H.

Cellular and Molecular Biology Letters

|

2000

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tom 05

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nr 2

3

The transcription reinitiation properties of RNA polymerase III in the absence of transcription factors

88%

Ferrari R., Dieci G.

Cellular and Molecular Biology Letters

|

2008

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tom 13

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nr 1

112-118

Transcription reinitiation by RNA polymerase (Pol) III proceeds through facilitated recycling, a process by which the terminating Pol III, assisted by the transcription factors TFIIIB and TFIIIC, rapidly reloads onto the same transcription unit. To get further insight into the Pol III transcription mechanism, we analyzed the kinetics of transcription initiation and reinitiation of a simplified in vitro transcription system consisting only of Pol III and template DNA. The data indicates that, in the absence of transcription factors, first-round transcription initiation by Pol III proceeds at a normal rate, while facilitated reinitiation during subsequent cycles is compromised.

4

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Unraveling protein-protein interactions using fluorescence imaging techniques

75%

Michalak M., Wojtaszek P.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

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2013

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tom 94

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nr 3

5

The role of STAT5 proteins in the regulation of normal hematopoiesis in a cord blood model

75%

Baskiewicz-Masiuk M., Masiuk M., Czajka R., Machalinski B.

Cellular and Molecular Biology Letters

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2003

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tom 08

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nr 2

The signal transducers and activators of transcription - STAT5A and STAT5B - are responsible for the control of proliferation, differentiation and apoptosis, via their effect on gene expression. They are activated by the binding of many cytokines, growth factors and hormones to their receptors on the cell surface. Many of these cytokines regulate hematopoietic cell development; therefore, STAT5 proteins are suggested to play an important role in hematopoiesis. There are numerous contradictory reports available in the literature on the role of STAT5 in normal hematopoietic cell development; hence, the question of the real function of STAT5 proteins clearly requires further studies. The aim of our study was to evaluate the role of STAT5 in normal hematopoiesis using oligodeoxynucleotide (ODN) strategy against STAT5 mRNA. We employed the RT-PCR method to study STAT5 mRNA expression in cells after their incubation with ODNs. We analyzed the effect of blocking STAT5 proteins on the viability and clonogenecity of the CFU-GM (Colony Forming Unit of Granulocyte-Macrophages) and the BFU-E (Burst Forming Unit of Erythrocytes) obtained from human cord blood (CB). The clonogenic growth of the cells was assessed in methylcellulose cultures according to the type of oligodeoxynucleotides. We also attempted to estimate the level of apoptosis induced in cord blood mononuclear and CD34+ cells by employing different assays: i) Annexin V staining using flow cytometry (FACSCalibur); ii) terminal deoxynucleotidyltransferase dUTP nick end labeling (TUNEL); iii) analysis of Bax and Bcl-XL gene expression by RT-PCR. Perturbation of STAT5 expression with antisense oligodeoxynucleotides had no impact on the viability, clonogenecity and apoptosis of CB hematopoietic cells. Our results showed that STAT5 proteins do not play a significant role in the regulation of proliferation of normal hematopoietic cells derived from cord blood.

6

Studies of HIV-Rev in living cells

75%

Brokstad K. A., Andersen V., Kanestrom A., Szilvay A. M., Haukenes G., Kalland K. H.

Cellular and Molecular Biology Letters

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1997

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tom 02

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nr 2

7

Novel yeast cell dehydrogenase activity assay in situ

75%

Berlowska J., Kregiel D., Klimek L., Orzeszyna B., Ambroziak W.

Polish Journal of Microbiology

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2006

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tom 55

|

nr 2

The aim of this research was to develop a suitable method of succinate dehydrogenase activity assay in situ for different industrial yeast strains. For this purpose different compounds: EDTA, Triton X-100, sodium deoxycholate, digitonin, nystatin and β-mercaptoethanol were used. The permeabilization process was controlled microscopically by primuline staining. Enzyme assay was conducted in whole yeast cells with Na-succinate as substrate, phenazine methosulfate (PMS) as electron carrier and in the presence one of two different tetrazolium salts: tetrazolium blue chloride (BT) or cyanoditolyl tetrazolium chloride (CTC) reduced during the assay. In comparabile studies of yeast vitality the amount of intracellular ATP was determined according to luciferin/luciferase method. During the succinate dehydrogenase assay in intact yeast cells without permeabilization, BT formazans were partially visualized in the cells, but CTC formazans appeared to be totally extracellular or associated with the plasma membrane. Under these conditions there was no linear relationship between formazan color intensity signal and yeast cell density. From all chemical compounds tested, only digitonin was effective in membrane permeabilization without negative influence on cell morphology. Furthermore, with digitonin-treated cells a linear relationship between formazan color intensity signal and yeast cell number was noticed. Significant decreasing of succinate dehydrogenase activity and ATP content were observed during aging of the tested yeast strains.

8

Cellular organelle transport and positioning by plasma streaming

75%

Wanka F., Van Zoelen E. J. J.

Cellular and Molecular Biology Letters

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2003

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tom 08

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nr 4

Our analysis of known data reveals that translocations of passively movable cellular organelles from tiny granules up to large cell nuclei can be ascribed to transport by streaming cytoplasm. The various behaviours, such as velocity changes during more or less interrupted movements, forth and back shuttling and particle rotation result from different types of plasma circulation. Fast movements over long distances, as observed in the large characean internodial cells occur in strong streams generated by myosin in bundles of actin filaments in the direction of the barbed filament ends. Slow movements with frequent reversions of the direction are typical for neuronal axons, in which an anterograde plasma flow, produced in a thin layer of membrane-attached actin filaments, is compensated by a retrograde stream, produced by dynein activity in the central bundle of microtubules. Here particle rotation is due to steep flow velocity gradients, and frequent changes of particle movements result from minor particle displacements in radial directions. Similar shuttling of pigment granules in the lobes of epidermal chromatophores results from the same mechanism, whereby the centrifugal movement along astral microtubules is due to flow generated by excess of kinesin activity and the centripetal movement to the plasma recycling through the intermicrotubular space. If the streaming pattern is reversed by switching to excess dynein activity, the moving granules are trapped in the high microtubule density at the aster center. The presence of larger bodies in asters disturbs the regular, kinesin-dependent microtubule distribution in such a way that a superimposed centrifugal plasma flow develops in the microtubule-dense layer along them, which is recycled in the microtubule-free space, created by their presence. Consequently, at excess kinesin activity, nuclei, mitochondria as well as chromosome fragments move towards the aster center until they reach a dynamically stabilized position that depends on the local microtubule density. These various behaviours are not rationally explainable by models based on a mechanical stepping along microtubules or actin filaments.

9

Biosensors of protein kinase action: from in vitro assays to living cells

75%

Lawrence D. S.

Cellular and Molecular Biology Letters

|

2003

|

tom 08

|

nr 2A

10

On the possible methods for the mathematical description of the ball and chain model of ion channel inactivation

63%

Malysiak K., Grzywna Z. J.

Cellular and Molecular Biology Letters

|

2008

|

tom 13

|

nr 4

535-552

Ion channels are large transmembrane proteins that are able to conduct small inorganic ions. They are characterized by high selectivity and the ability to gate, i.e. to modify their conductance in response to different stimuli. One of the types of gating follows the ball and chain model, according to which a part of the channel’s protein forms a ball connected with the intracellular side of the channel by a polypeptide chain. The ball is able to modify the conductance of the channel by properly binding to and plugging the channel pore. In this study, the polypeptide ball is treated as a Brownian particle, the movements of which are limited by the length of the chain. The probability density of the ball’s position is resolved by different diffusional operators — parabolic (including the case with drift), hyperbolic, and fractional. We show how those different approaches shed light on different aspects of the movement. We also comment on some features of the survival probabilities (which are ready to be compared with electrophysiological measurements) for issues based on the above operators.

11

Possibilities and limitations of light microscopy in the study of the structure and function of a plant cell

63%

Kurczynska E.

BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology

|

2015

|

tom 96

|

nr 1

12

High-throughput interaction screening for the elucidation of protein kinase networks and the identification of protein kinase inhibitors

63%

Kruse C., Vasiliev S., Hanke S., Hennemann H.

Cellular and Molecular Biology Letters

|

2003

|

tom 08

|

nr 2A

13

Understanding evolution

63%

Barciszewski J., Legocki A. B.

Acta Biochimica Polonica

|

2001

|

tom 48

|

nr 2

14

The problem of water exchange by living cells in the light of mechanistic transport equations

63%

Kargol M., Suchanek G., Przestalski M., Siedlecki J., Kargol A.

Polish Journal of Environmental Studies

|

2005

|

tom 14

|

nr 5

Each living cell must, while performing its life functions, constantly exchange water with its surroundings. This occurs through the cell membrane. In the present paper, we have made an attempt to explain the biophysical basis of this water exchange, realized under stationary conditions, i. e. at constant cell volume. For the investigation, the mechanistic equations for membrane transport have been applied. It has been demonstrated that each living cell which subsists under stationary conditions is capable of water absorption and simultaneous water removal to its surroundings. Water absorption is osmosis-driven, while water removal is driven by the mechanical pressure difference (the turgor pressure). These are new, and very significant, research results. This stationary water exchange cannot be explained on the basis of thermodynamic transport equations.

15

Metabolic mapping by enzyme histochemistry in living animals, tissues and cells

51%

Van Noorden C. J. F.

Journal of Physiology and Pharmacology. Supplement

|

2009

|

tom 60

|

nr 4

16

A reinvestigation of the marine ciliate Trachelocerca ditis [Wright, 1982] Foissner and Dragesco, 1996 [Ciliophora, Karyorelictea] from the Yellow Sea and an assessment of its phylogenetic position inferred from the small subunit rRNA gene sequence

51%

Mazei Y., Gao S., Warren A., Li L., Li J., Song W., Esaulov A.

Acta Protozoologica

|

2009

|

tom 48

|

nr 3

213-221

17

Genetical and biochemical characterization of cycle krebs mutant in yeast

51%

Boniewska-Bernacka E., Lachowicz T. M., Kotylak Z.

Acta Microbiologica Polonica

|

1998

|

tom 47

|

nr 2

18

Morphometric and morphogenetic comparisons between Onychodromus indica sp.n. and O.quadricornutus Foissner, Schlegel et Prescott, 1987; phylogenetic note on Onychodromus and related genera

51%

Kamra K., Sapra G. R.

Acta Protozoologica

|

1993

|

tom 32

|

nr 2

19

Histological studies on callus and shoot induction in culture of Trifolium nigrescens Viv. in vitro

51%

Konieczny R.

Acta Biologica Cracoviensia. Series Botanica

|

2000

|

tom 42

|

nr 1

The development of callus and adventitious shoots from hypocotyl and cotyledon of Trifolium nigrescens seedlings was studied bjr light microscopy. Calli were formed by multiplication of all living cells of explants except for cotyledonary epidermis within the first week of culture on MS medium (Murashige and Skoog, 1962) supplemented with 0.5 mgl-1 NAA and 2 mgl-1 2iP. All the shoots induced from cotyledon- and hypocotyl-derived calli were of multicellular origin and resulted from meristematic cells at peripheral regions of the callus. Copious changes in starch content accompanying callus formation and shoot initiation indicate its significant role in organogenesis of T. nigrescens.

20

Biocompatibility of polymeric components of hydrogel macrocapsule for hybrid-type artificial pancreas

45%

Burczak K., Tatarkiewicz K., Sitarek E., Morzycka-Michalik M.

Bulletin of the Polish Academy of Sciences. Biological Sciences

|

1995

|

tom 43

|

nr 3-4

Ograniczanie wyników

Field-theoretical approach to the action potential

Law and order in the nucleus: dynamics of replication factories in living cells

The transcription reinitiation properties of RNA polymerase III in the absence of transcription factors

Unraveling protein-protein interactions using fluorescence imaging techniques

The role of STAT5 proteins in the regulation of normal hematopoiesis in a cord blood model

Studies of HIV-Rev in living cells

Novel yeast cell dehydrogenase activity assay in situ

Cellular organelle transport and positioning by plasma streaming

Biosensors of protein kinase action: from in vitro assays to living cells

On the possible methods for the mathematical description of the ball and chain model of ion channel inactivation

Possibilities and limitations of light microscopy in the study of the structure and function of a plant cell

High-throughput interaction screening for the elucidation of protein kinase networks and the identification of protein kinase inhibitors

Understanding evolution

The problem of water exchange by living cells in the light of mechanistic transport equations

Metabolic mapping by enzyme histochemistry in living animals, tissues and cells

A reinvestigation of the marine ciliate Trachelocerca ditis [Wright, 1982] Foissner and Dragesco, 1996 [Ciliophora, Karyorelictea] from the Yellow Sea and an assessment of its phylogenetic position inferred from the small subunit rRNA gene sequence

Genetical and biochemical characterization of cycle krebs mutant in yeast

Morphometric and morphogenetic comparisons between Onychodromus indica sp.n. and O.quadricornutus Foissner, Schlegel et Prescott, 1987; phylogenetic note on Onychodromus and related genera

Histological studies on callus and shoot induction in culture of Trifolium nigrescens Viv. in vitro

Biocompatibility of polymeric components of hydrogel macrocapsule for hybrid-type artificial pancreas