Wyniki wyszukiwania - Biblioteka Nauki

1

Dichroizm kołowy kwasów nukleinowych. Cz.2. Polimery

100%

Boczkowska M.

Wiadomości Chemiczne

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2002

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tom [Z] 56, 3-4

203--221

EN

The review presents the theoretical basis for interpretations of CD spectra of polynucleotides. A simplified version of quantum theory of circular dichroism of a polynucleotide by Tinoco and Johnson is presented in details. It is generally assumed that the optical activity of these polymers is dominated by interactions between dipoles of in-plane transitions occuring at neighbouring bases. The interaction of dipoles coming from different bases strictly depends on geometrical arrangement of bases within the helix. As a result information about geometry of the helix can be inferred from the CD spectra. The circular dichroism caused by the disturbance of the electronic system of a base by the presence of a sugar ring is usually omitted in calculations. Such a theoretical approach allows to understand differences between CD spectra of random DNA and RNA. The distance of a base pair from helix axis appeared to be the main factor responsible for these differences]. The approach fails in a case of polymers of non-random sequences, for example containing a repetitive motif of two bases. It is exemplified for the d(CG)n oligomers forming left-handed double helix called Z-DNA, where none of the theoretical calculations is able to predict the inversion of a CD spectrum characteristic for the Z form .

2

Termodynamiczne aspekty powstawania oligonukleotydowych struktur dwuniciowych i ich wplyw na selektywnosc hybrydyzacji w strategii antysensowej

63%

Boczkowska M. , Guga P.

Biotechnologia

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1994

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nr 4

59-68

3

Starzenie się nasion - podstępny wróg zachowania różnorodności biologicznej w bankach genów

51%

Boczkowska M. , Rucinska A. , Targonska-Karasek M. , Niedzielski M.

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nr 283

4

Ocena przydatności loci barkodowych do identyfikacji gatunków roślin łąk i muraw kserotermicznych. Komunikat

51%

Boczkowska M. , Rucinska A. , Olszak M. , Nowak A.

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2020

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nr 288

5

Unusual thermal stability of RNA/[All-RP-PS]-DNA/RNA triplexes containing a homopurine DNA strand

45%

Boczkowska M. , Guga P. , Janicka M. , Maciaszek A. , Stec W.

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nr Supplement 1

6

Starzenie się nasion - złożony problem banków genów. Praca przeglądowa

38%

Boczkowska M. , Rucinska A. , Targonska-Karasek M. , Olszak M. , Niedzielski M. , Rakoczy-Trojanowska M.

Agronomy Science

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2018

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tom 73

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nr 4

7

Antisense hairpin loop oligonucleotides as inhibitors of expression of multidrug resistance-associated protein 1: Their stability in fetal calf serum and human plasma

38%

Rebowski G. , Wojcik M. , Boczkowska M. , Gendaszewska E. , Soszynski M. , Bartosz G. , Niewiarowski W.

Acta Biochimica Polonica

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2001

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tom 48

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nr 4

EN

Multidrug resistance-associated protein (MRP1) is a transmembrane pump protein responsible for the efflux of chemotherapeutic drugs, an important cause of anticancer treatment failure. Trying to circumvent MRP-mediated resistance we designed and synthesized hairpin loops forming antisense oligodeoxyribonucleotides (ODNs), both phosphodiesters (PO-ODNs) and their phosphorothioate analogues (PS-ODNs), to reduce the protein expression by targeting its mRNA in a sequence specific manner. Melting temperature measurements as well as polyacrylamide gel elec- trophoresis supported the preferential formation of a secondary structure, which was expected to protect ODNs against 3-exonuclease degradation. ODNs and PS-ODNs designed in this work were successfully tested as antisense inhibitors of the expression of MRP1 in the leukaemia HL60/ADR cell line. Foreseeing the necessity to perform clinical studies with such ODNs we investigated their stability against the 3 -exonuclease activity of fetal calf serum and human plasma. Under the conditions, corresponding to physiological ones, we observed high stability of hairpin loop forming ODNs, especially those containing longer (e.g. 7 base pair) stems. Comparative studies on the stability of chemically unmodified hairpin loop forming ODNs and their PS-counterparts indicated that endonuclease activity did not play any important role in the process of their nucleolytic degradation. Our studies provide strong evidence for high stability of chemically unmodified hairpin loop ODNs, making them an attractive alternative to phosphorothioate analogues commonly used in antisense strategy.

8

Identyfikacja zmienności genetycznej pszenicy korelującej z potencjałem plonotwórczym i wybranymi cechami systemu korzeniowego

32%

Nadolska-Orczyk A. , Szala K. , Ogonowska H. , Rajchel I. , Wyszynska R. , Boczkowska M. , Gasparis S. , Kala M.

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nr 295

9

Inhibition of plasminogen activator inhibitor release in endothelial cell cultures by antisense oligodeoxyribonucleotides with a 5' -end lipophilic modification

26%

Kobylanska A. , Pluskota E. , Swiatkowska M. , Wojcik M. , Cierniewska-Cieslak A. , Krakowiak A. , Boczkowska M. , Pawlowska Z. , Okruszek A. , Koziolkiewicz M. , Cierniewski C. S. , Stec W. J.

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tom 46

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nr 3

EN

A series of conjugates containing residues of lipophilic alcohols covalently bound to 5'-end of oligodeoxyribonucleotides targeted against human plasminogen activator inhibitor (PAI-1) mRNA was synthesized via the oxathiaphospholane approach. The highest anti-PAI-1 activity in EA.hy 926 endothelial cell cultures was found for conjugates containing menthyl or heptadecanyl groups linked with an oligonucleotide complementary to a segment of human PAI-1 mRNA. The phosphodiester antisense oligonucleotides, which otherwise exhibit only limited anti-PAI-1 activity, were found to be more active than phosphorothioate oligonucleotides when conjugated to lipophilic alcohol residues. For menthyl conjugates an evidence of antisense mechanism of inhibition was found.