PSJD - Yadda

1

Pharmacological attenuation of Paramecium fluid-phase endocytosis

100%

Wiejak J., Surmacz L., Wyroba B.

Folia Biologica

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2007

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vol. 55

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issue 3-4

95-100

EN

Spectrophotometric quantification of fluid phase endocytosis in the presence of different pharmacological compounds was performed in the model unicellular eukaryote Paramecium. The kinetics of Lucifer Yellow Carbohydrazide (LY) uptake in cells exposed to forskolin and isoproterenol ? known to stimulate phagocytosis in this cell ? was analyzed. Reduction in both the rate of endocytosis and total accumulation of fluid phase marker was observed following the treatment. Forskolin diminished total LY accumulation by 11% and 21% after 5 min and 25 min of incubation, respectively, whereas the rate of uptake was lowered by 21% in comparison to control cells. The inhibitory effect of isoproterenol was less pronounced than that of forskolin. The total accumulation of LY was decreased by 11% in 5 min as compared to the untreated cells and this effect was persistent upon further exposition to this reagent up to 25 min. To better understand these observations, the effect of inhibitors of PKA and cAMP phosphodiesterase on fluid phase uptake was tested. 3-isobutyl-1-methyl xanthine (IBMX) caused 12% decrease in LY accumulation after 5 min of incubation. In combination with isoproterenol or forskolin, IBMX enhanced their inhibitory effect on fluid endocytosis, which was lowered by 25% and 29%, respectively. The strongest inhibitory effect on fluid endocytosis was exerted by the 10 _M PKA inhibitor, which diminished endocytosis by 35% in 5 min. These results suggest that Paramecium fluid phase uptake may be regulated through activation of PKA, although the precise mechanism of this process has not yet been elucidated.

2

Receptor-mediated endocytosis ? function and participation in oral drug delivery.

100%

Zuwala-Jagiello J.

Postępy Higieny i Medycyny Doświadczalnej

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2003

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vol. 57

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issue 3

275-291

EN

The rapid expansion of applied biotechnology research in current pharmaceutical drug discovery has resulted in the development of increasing numbers of novel macromolecular therapeutics. Oral bioavailability of these compounds is usually poor due to a combination of incompatible physicochemical properties, resulting in low cellular penetration, and high susceptibility to metabolic enzymes present within the gastrointestinal tract. For chronic drug therapy, however, the oral pathway is generally considered to be the most convenient route of administration. Thus far, limited success has been observed in oral macromolecular delivery by either concomitant administration of penetration enhances or the use of prodrug strategies involving carrier-mediated transport systems. An alternative approach may be targeting to receptor-mediated endocytosis (RME) systems. It is the aim of this mini-review to present a concise overview of the latest developments in RME research and RME systems that are either currently targeted for the oral delivery of macromolecules or may appear to become potential targets for future oral drug delivery strategies.

3

Oligonucleotide transport across the plasma membrane

75%

Laski J.

Biotechnologia

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1994

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issue 4

40-49

EN

Transport of synthetic oligonucleotides across the plasma membrane of mammlian cells is the one of the major problems in the application of the antisense strategy.Modifications of oligonucleotides may improve their transport and stability in the cell's medium.The therapeutical agents tergeted to intracellular structures and their mechanisms are reviewed.

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1 Biotechnologia

1 Folia Biologica

1 Postępy Higieny i Medycyny Doświadczalnej

1 2007

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1 1994

1 Laski J.

1 Surmacz L.

1 Wiejak J.

1 Wyroba B.

1 Zuwala-Jagiello J.

Search results

Pharmacological attenuation of Paramecium fluid-phase endocytosis

Receptor-mediated endocytosis ? function and participation in oral drug delivery.

Oligonucleotide transport across the plasma membrane