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Rozpoznanie częściowego napromienienia ciała przy pomocy testu mikrojądrowego

Sommer Sylwester, Buraczewska Iwona, Kruszewski Marcin

Postępy Techniki Jądrowej

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2019

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z. 2

30--32

PL

Dozymetria biologiczna oprócz oszacowania wysokości dawki powinna mieć możliwość rozpoznawania czy napromienione zostało całe ciało, czy tylko jego część. Bardzo dobrze sprawdza się tutaj test chromosomów dicentrycznych, jednak prowadzone są prace również z innymi testami dozymetrycznymi. Wyniki badań wskazują, że test mikrojądrowy nie pozwala jednoznacznie na rozpoznawanie częściowego napromienienia ciała.

EN

Biological dosimetry in addition to the estimation of the absorbed dose should be able to recognize whole or partial body irradiation. The dicentric chromosome test works very well here, however, other dosimetry tests are being examined to recognize partial body irradiation. The research results indicate that the micronucleus test does not explicitly allow the recognition of such a situation.

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Strategiczny projekt badawczy Narodowego Centrum Badań i Rozwoju pt. " Technologie wspomagające rozwój bezpiecznej energetyki jądrowej" Zadanie nr 6. Rozwój metod zapewnienia bezpieczeństwa jądrowego i ochrony radiologicznej dla bieżących i przyszłych potrzeb energetyki jądrowej. Cel 2: Rozwój metod dozymetrii biologicznej oraz biofizycznych markerów i indykatorów wpływu promieniowania na organizmy żywe. (Etapy 6, 7, 8, 9, i 10)

Brzóska K., Kowalska M., Kruszewski M., Lankoff A., Sommer S.

Postępy Techniki Jądrowej

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2015

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z. 2

42--46

PL

Dozymetria biologiczna pozwala odczytać dawkę pochłoniętą promieniowania jonizującego w organizmie i jest niezbędnym elementem systemu ochrony radiologicznej. Aby zapewnić większą wiarygodność uzyskanych wyników metoda analizy dicentryków zostanie akredytowana w 2 laboratoriach, a w jednym istniejąca akredytacja zostanie rozszerzona o biodozymetrię mieszanego promieniowania gamma i neutronowego. Jedną ze strategii dostosowania dozymetrii biologicznej do scenariusza masowego zdarzenia jest łączenie laboratoriów we współdziałającą sieć. Założenia takiej sieci zostały opracowane i opisane. W trakcie projektu wypróbowano nowe, obiecujące metody: analizę ekspresji genów (m.in. FDXR, GADD45A) na poziomie mRNA z wykorzystaniem techniki PCR oraz metody oparte na PCC (przedwczesnej kondensacji chromosomów), w szczególności RICA (The Rapid Interphase Chromosome Assay). Obie metody okazały się skutecznymi metodami dozymetrii biologicznej.

EN

Biological dosimetry allows to read the absorbed dose of ionizing radiation in the body and is an essential element of the system of radiological protection. To ensure greater reliability of the results obtained by dicentric assay method will be accredited in 2 laboratories, and one existing accreditation will be extended to biodosimetry of mixed gamma and neutron radiation. One of the strategies to adapt biological dosimetry to the mass events scenario is to combine laboratories in cooperating network. Assumptions of such a network have been developed and described. The new methods of biological dosimetry have been investigated: analysis of gene expression (including FDXR, GADD45A) at the mRNA level using PCR method and methods based on the PCC (premature chromosome condensation), in particular RICA (The Interphase Chromosome Rapid Assay). Both methods have proven to be effective methods of biological dosimetry.

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Application of the micronucleus assay performed by different scorers in case of large-scale radiation accidents

Rawojć K., Tarnawska D. M., Miszczyk J. U., Swakoń J., Stolarczyk L., Rydygier M.

Nukleonika

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2015

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Vol. 60, No. 3, part 2

643--649

EN

Mass casualty scenarios of radiation exposure require high throughput biological dosimetry techniques for population triage, in order to rapidly identify individuals, who require clinical treatment. Accurate dose estimates can be made by biological dosimetry, to predict the acute radiation syndrome (ARS) within days after a radiation accident or a malicious act involving radiation. Timely information on dose is important for the medical management of acutely irradiated persons [1]. The aim of the study was to evaluate the usefulness of the micronuclei (MNi) scoring procedure in an experimental mode, where 500 binucleated cells were analyzed in different exposure dose ranges. Whole-body exposure was simulated in an in vitro experiment by irradiating whole blood collected from one healthy donor with 60 MeV protons and 250 keV X-rays, in the dose range of 0.3–4.0 Gy. For achieving meaningful results, sample scoring was performed by three independent persons, who followed guidelines described in detail by Fenech et al. [2, 3]. Compared results revealed no signifi cant differences between scorers, which has important meaning in reducing the analysis time. Moreover, presented data based on 500 cells distribution, show that there are significant differences between MNi yields after 1.0 Gy exposure of blood for both protons and X-rays, implicating this experimental mode as appropriate for the distinction between high and low dose-exposed individuals, which allows early classification of exposed victims into clinically relevant subgroups.

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Modelling the frequencies of chromosomal aberrations in peripheral lymphocytes of patients undergoing radiotherapy

Urbanik W., Kukołowicz P., Kuszewski T., Góźdź S., Wójcik A.

Nukleonika

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2003

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Vol. 48, nr 1

3-8

EN

Recently, several attempts have been undertaken to correlate in vitro calibration curves with observed frequencies of chromosomal aberrations and micronuclei in lymphocytes of patients undergoing radiotherapy. The aim of such correlations is the search for a biological method to reconstruct the dose received during radiotherapy. While the in vitro dose-response curves are linear-quadratic, the observed in vivo relationship is usually linear and there is some controversy as to the nature of the observed linearity. We have, therefore, constructed a model to calculate the frequencies and distributions of chromosomal aberrations in lymphocytes of patients undergoing conventional radiotherapy. The model assumes that each fraction of radiation induces a certain number of Poisson-distributed aberrations in the irradiated blood volume. In addition, a simplified assumption is made that lymphocytes flow freely inside the body of the patient and no elimination of cells occurs. The model yields linear dose response curves. The steepness of the curves increases with increasing size of irradiated block of tissue (referred to as irradiated volume) and increasing dose per fraction. The distributions of aberrations become increasingly overdispersed with increasing dose per fraction but are independent of the number of radiation fractions. The modelled dose-response curves agree well with the majority of published experimental results. Given the simple assumptions made, this indicates that cell elimination, which occurs during radiotherapy does not bias the results obtained experimentally. The linearity of the dose response-curve results from the fractionated irradiation. Hence, great care should be applied when attempting to use standard, linear-quadratic calibration curves to estimate the doses received by patients during radiotherapy.