Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "ionizing radiation" wg kryterium: Temat


Wyświetlanie 1-4 z 4
Tytuł:
Changes in phosphorylation of histone H2A.X and p53 in response of peripheral blood lymphocytes to gamma irradiation
Autorzy:
Vilasová, Zdeňka
Řezáčová, Martina
Vávrová, Jiřina
Tichý, Aleš
Vokurková, Doris
Zoelzer, Friedo
Řeháková, Zuzana
Osterreicher, Jan
Lukášová, Emilie
Powiązania:
https://bibliotekanauki.pl/articles/1040760.pdf
Data publikacji:
2008
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
lymphocyte
ionizing radiation
p53
phytohemagglutinin (PHA)
apoptosis
DNA damage
Opis:
The main aim of this study was to compare the reaction of quiescent and proliferating, i.e. phytohemagglutinin (PHA)-stimulated, human peripheral blood mononuclear cells (PBMCs) to γ-radiation, and analyse changes of proteins related to repair of DNA damage and apoptosis, such as γH2A.X, p53, p53 phosphorylation at serines-15 and -392, and p21 and their dose dependence. Freshly isolated PBMCs in peripheral blood are predominantly quiescent, in G0 phase, and with very low amounts of proteins p53 and p21. Using confocal microscopy we detected dose dependent (0.5-5 Gy) induction of foci containing γH2A.X (1 h after γ-ray exposure), which are formed around radiation-induced double strand breaks of DNA. Apoptosis was detected from 24 h after irradiation by the dose of 4 Gy onwards by Annexin V binding and lamin B cleavage. Seventy two hours after irradiation 70% of CD3+ lymphocytes were A+. Neither increase in p53 nor its phosphorylation on serine-392 after irradiation was detected in these cells. However, massive increase in p21 (cyclin-dependent kinase inhibitor 1A) was detected after irradiation, which can be responsible for late occurrence of apoptosis in these quiescent cells. PHA-stimulation itself (72 h) caused an increase in early apoptosis (A+PI-) in comparison to non-stimulated PBMCs (38% A+ resp. 13.4%). After PHA-stimulation also the amount of γH2A.X, p53, and p21 increased, but no phosphorylation of p53 on serine-392 or -15 was detected. Reaction to γ-radiation was different in PHA-stimulated lymphocytes: the p53 pathway was activated and p53 was phosphorylated on serines-15 and -392 4 h after irradiation by the dose of 4 Gy. Phosphorylation of p53 at serine-15 increased in a dose-dependent manner in the studied dose range 0.2-7.5 Gy. Also the amount of p21 increased after irradiation. Seventy two hours after irradiation of PHA-stimulated CD3+ T lymphocytes by the dose of 4 Gy 65% of cells were A+.
Źródło:
Acta Biochimica Polonica; 2008, 55, 2; 381-390
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
5',8-Cyclo-2'-deoxyadenosine (cdA) formation by γ-radiation. Theoretical quantum mechanics study
Autorzy:
Karwowski, Boleslaw
Grand, Andre
Cadet, Jean
Powiązania:
https://bibliotekanauki.pl/articles/1040482.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
5',8-cyclo-2'-deoxyadenosine
DNA damage
ionizing radiation
density functional theory (DFT)
Opis:
Reactions of reactive oxygen species and more specifically - of hydroxyl radical (•OH) - with nucleosides may lead to the generation of radicals in the base and 2-deoxyribose moieties. In the present study emphasis was put on the possible reaction modes of 2'-deoxyadenosine (dA) radicals, leading to the formation of related 5',8-cyclonucleosides. It appears that the prerequisite for the formation of 5',8-cyclo-2'-deoxyadenosine (cdA) is the adoption of O4'-exo conformation by 2-deoxyribose; however, this is the least energetically favored conformer among the different puckered forms adopted by the furanose ring. The O4'-exo conformation was found to be present in each of the discussed mechanisms.
Źródło:
Acta Biochimica Polonica; 2009, 56, 4; 655-662
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DNA damage and repair in lymphocytes of normal individuals and cancer patients: studies by the comet assay and micronucleus tests.
Autorzy:
Palyvoda, Olena
Polańska, Joanna
Wygoda, Andrzej
Rzeszowska-Wolny, Joanna
Powiązania:
https://bibliotekanauki.pl/articles/1043662.pdf
Data publikacji:
2003
Wydawca:
Polskie Towarzystwo Biochemiczne
Tematy:
ionizing radiation
DNA damage
human lymphocytes
comet assay
head and neck tumors
DNA repair
Opis:
A population study is reported in which the DNA damage induced by γ-radiation (2 Gy) and the kinetics of the subsequent repair were estimated by the comet and micronucleus assays in isolated lymphocytes of 82 healthy donors and patients with head and neck cancer before radiotherapy. The parameters of background and radiation-induced DNA damage, rate of repair, and residual non-repaired damage were measured by comet assay, and the repair kinetics for every donor were computer-fitted to an exponential curve. The level of background DNA damage before irradiation measured by comet assay as well as the level of micronuclei were significantly higher in the head and neck cancer patient group than in the healthy donors, while the parameters of repair were widely scattered in both groups. Cancer patient group contained significantly more individuals, whose irradiated lymphocytes showed high DNA damage, low repair rate and high non-repaired DNA damage level. Lymphocytes of donors belonging to this subgroup showed significantly lower inhibition of cell cycle after irradiation.
Źródło:
Acta Biochimica Polonica; 2003, 50, 1; 181-190
0001-527X
Pojawia się w:
Acta Biochimica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
DNA damage in subpopulations of human lymphocytes irradiated with doses in the range of 0-1 Gy of X-radiation
Autorzy:
Wojewódzka, M.
Machaj, E. K.
Goździk, A.
Iwaneńko, T.
Ołdak, T.
Kruszewski, M.
Pojda, Z.
Powiązania:
https://bibliotekanauki.pl/articles/147760.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
alkaline comet assay
biodosimetry
micronucleus test
histone gammaH2AX foci immunofluorescence assay
T lymphocytes
B lymphocytes
ionizing radiation
DNA damage
Opis:
We compared three methods usually applied in biological dosimetry for estimation of radiation-induced DNA damage in human T and B lymphocytes: alkaline comet assay, micronucleus (MN) test and formation of histone gamma-H2AX foci. Human peripheral blood lymphocytes were fractionated using T cells and B cells isolation kits. Cells were irradiated with doses in the range of 0-1 Gy of X-rays. Induction of DNA damage was assessed by the standard alkaline comet assay, MN test and histone gammaH2AX foci immunofluorescence assay. Notwithstanding different end-points measured by the applied methods, all tests revealed a similar induction of DNA damage in B lymphocytes as compared with T lymphocytes. The results indicated that all three tests detect DNA damage with similar sensitivity, the lowest dose being approximately 0.3 Gy. The difference between irradiated and control cells was expressed as the ratio of the value obtained for irradiated cells (1 Gy) to that for control cells. The highest ratio was obtained for formation of gammaH2AX foci and was 6.2 for T and 13.8 for B lymphocytes, whereas those for comet assay and micronucleus test were 3.5; 3.6 and 5.6; 4.8, respectively.
Źródło:
Nukleonika; 2008, 53, 4; 145-149
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
    Wyświetlanie 1-4 z 4

    Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies