Abstract:
PURPOSE:To investigate the potential total and relative free-radical transfer from histones to DNA in X-irradiated chromatin, by analysing the relative contributions of individual radicals from protein and from DNA. MATERIALS AND METHODS:Chromatin was isolated from calf thymus, freeze-dried and either used as such or after equilibration at 76% relative humidity. A mixture of histones was purchased. X-irradiation was performed at 77 K (liquid nitrogen). Data acquisition was on a Bruker ESP 380 ESR-spectrometer (X-band, 9.5 GHz) and at high magnetic fields (285 GHz, Y-band, GHMFL Grenoble). Data analysis involved computer treatment of spectra. RESULTS:Three components were isolated from an annealing series of histones and assigned to specific radicals (X-band). Chromatin revealed the existence of radicals from both DNA, as well as from the histone compartment. The presence of the oxidized guanine base, as well as the reduced cytosine and thymine bases from DNA at 77 K was confirmed by high-field ESR. Relative radical yields were determined by superposition of individual components from DNA and histones in order to give complete reconstructions of the experimental spectra of the annealing series. CONCLUSIONS:The relative yields of individual radicals in chromatin differ from those in histones or DNA, respectively. Their behaviour upon annealing is, on the other hand, not significantly changed. Since the total radical yield of DNA radicals is about two times higher in the chromatin complex than in pure DNA, the hypothesis of spin transfer from protein to DNA prior to radical stabilization at 77 K is substantiated.
journal_name
Int J Radiat Bioljournal_title
International journal of radiation biologyauthors
Weiland B,Hüttermann Jdoi
10.1080/09553000050111541subject
Has Abstractpub_date
2000-08-01 00:00:00pages
1075-84issue
8eissn
0955-3002issn
1362-3095journal_volume
76pub_type
杂志文章abstract:PURPOSE:To examine the heat sensitivity of DNA-dependent protein kinase (DNA-PK) activity in a variety of cultured mouse, hamster and human cell lines. MATERIALS AND METHODS:Eight cell lines, which have been routinely used in our laboratory, were examined. Cells were heated at 44.0 +/- 0.05 degrees C and DNA-PK activi...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553000310001596959
更新日期:2003-08-01 00:00:00
abstract::The relationship between ionizing radiation-induced cell killing and DNA damage measured by the micronucleus and apoptosis assays was determined in three established cell lines (L929, HL-60, and Chang). Irradiation experiments revealed a dose-dependent increase of micronucleated cells until a certain dose was reached....
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009514550371
更新日期:1995-03-01 00:00:00
abstract:PURPOSE:The main aim of the present study is to gain mechanistic insights into the modulating effect of molecular hydrogen on the γ-radiation-induced alteration pathways of DNA nucleobases. MATERIALS AND METHODS:Aerated aqueous solutions of calf thymus DNA were exposed to a (60)Co source at doses ranging from 0 to 55 ...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553002.2016.1206234
更新日期:2016-09-01 00:00:00
abstract:PURPOSE:To present details of the recent version of the 'Local Effect Model' (LEM), that has been developed and implemented in treatment planning for the ion beam therapy pilot project performed at GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. MATERIALS AND METHODS:The new version of the model i...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2011.611213
更新日期:2012-01-01 00:00:00
abstract::Primary chick embryo myoblasts can be a useful tool for studying the developmental events which accompany myoblast differentiation, particularly myoblast membrane fusion. To determine whether the electrical properties and/or fusion in these systems are affected by 50 Hz magnetic fields, chick embryo myoblast cultures ...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:
更新日期:1991-12-01 00:00:00
abstract:PURPOSE:To resolve the difficulty in counting merged DNA damage foci in high-LET (linear energy transfer) ion-induced patterns. MATERIALS AND METHODS:The analysis of patterns of RIF (radiation-induced foci) produced by high-LET Fe and Ti ions were conducted by using a Monte Carlo model that combines the heavy ion trac...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553001003717175
更新日期:2010-06-01 00:00:00
abstract:PURPOSE:The low dose (<1 Gy) survival curve of mammalian cells is characterized by a region of hypersensitivity (HRS) followed by increased resistance (IRR). Above 1 Gy, the survival response can be described with a smooth downward-bending curve. Indirect evidence has indicated that the IRR response might reflect an in...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/095530000138646
更新日期:2000-03-01 00:00:00
abstract:PURPOSE:Many studies have shown that exposure to radiofrequency radiation (RFR) could activate cellular signal transduction pathways. In the present research, we investigated the effects of exposure to a 1.8-GHz RFR at different intensities on epidermal growth factor (EGF) receptor clustering and phosphorylation in hum...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2011.634882
更新日期:2012-03-01 00:00:00
abstract::One of the important temporal stages of radiation action in cellular systems is the chemical phase, where oxygen fixation reactions compete with chemical repair reactions involving reducing agents such as GSH. Using the gas explosion technique it is possible to follow the kinetics of these fast (greater than 1 ms) rea...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009214551571
更新日期:1992-06-01 00:00:00
abstract:PURPOSE:Public concern about radiation protection of the environment and non-human species is increasing. The potential impact of chronic gamma radiation on the bacterial community in a rice paddy ecosystem was investigated. MATERIALS AND METHODS:Paddy field microcosm samples were continuously exposed at a dose rate o...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2010.549534
更新日期:2011-07-01 00:00:00
abstract:PURPOSE:To test the importance of serotonin as a signaling molecule involved in the production and response of radiation-induced bystander effects. MATERIALS AND METHODS:HPV-G human keratinocyte cultures were spiked with various concentrations of Granisetron or Ketanserin and subject to either 0 Gy or 0.5 Gy X-irradia...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2012.714519
更新日期:2012-10-01 00:00:00
abstract::Solid human tumours contain areas with low oxygen tension (pO2). For bioreductive drugs it is important to define the cytotoxic effect according to drug concentration and to clinically relevant pO2. In this study, the pO2 dependence of the survival of three human cell lines (HRT 18, Na11 +, and MEWO), exposed to tirap...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009514550261
更新日期:1995-02-01 00:00:00
abstract:PURPOSE:To describe the design and dosimetric characterization of a simple and economical small animal irradiator. MATERIALS AND METHODS:A high dose rate (HDR) (192)Ir brachytherapy source from a commercially available afterloader was used with a 1.3 cm thick tungsten collimator to provide sharp beam penumbra suitable...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2014.922719
更新日期:2014-10-01 00:00:00
abstract::Existing models of chromosome aberrations produced by ionizing-radiation predict equal numbers of dicentrics and translocations if the dose is so low that complex aberrations can be ignored. We show that, for a specific subset of aberrations detected by FISH, dicentric/translocation equality is predicted even at highe...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/095530096145977
更新日期:1996-02-01 00:00:00
abstract::SR 2508 (etanidazole) (1 mM) or buthionine sulphoximine (BSO, 50 microM) or both drugs together did not radiosensitize oxic V79 Chinese hamster cells irradiated at either an acute dose rate (2.35 Gy/min) or at a low dose rate (0.117 Gy/min). BSO pretreatment (15 h at 37 degrees C) depleted cellular glutathione (GSH) t...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009114550121
更新日期:1991-01-01 00:00:00
abstract:PURPOSE:To determine the radiosensitivity difference of human Cluster of Differentiation (CD)4(+)CD25(+) regulatory T cells (Treg) and effector T cells to low dose gamma ray and elucidate the underlying mechanisms in vitro. MATERIALS AND METHODS:Blood samples were collected from five health subjects and five patients ...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2010.518208
更新日期:2011-01-01 00:00:00
abstract:PURPOSE:To give a state-of-the-art overview on the promise of three-dimensional (3-D) culture systems for anticancer drug development, with particular emphasis on multicellular tumor spheroids (MCTS). RESULTS AND CONCLUSIONS:Cell-based assays have become an integral component in many stages of routine anti-tumor drug ...
journal_title:International journal of radiation biology
pub_type: 杂志文章,评审
doi:10.1080/09553000701727531
更新日期:2007-11-01 00:00:00
abstract::Radiation-induced DNA double-strand breaks (dsbs) were measured in CHO-K1 cells by means of an experimental approach involving constant-field gel electrophoresis and densitometric scanning of ethidium bromide stained gels. For X-irradiation, an induction efficiency of 36 +/- 5 dsbs (Gy x cell)-1 was determined. With t...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009514551051
更新日期:1995-08-01 00:00:00
abstract:PURPOSE:Animal models that accurately reflect human responses to radiation injury are needed for advanced mechanistic investigation and development of effective therapeutics. The rabbit is an established animal model accepted by the FDA for studies of cardiovascular disease, lipid metabolism, the development of anticoa...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553002.2020.1820606
更新日期:2020-10-26 00:00:00
abstract:PURPOSE:Detection of gene targets applicable to biological dosimetry and early detection of radiation-induced cell damage. MATERIALS AND METHODS:MCF-7 human mammary carcinoma cells were exposed to 2 and 6 Gy X-rays. Expression of 1176 genes was traced with the Atlas Human 1.2 Array (Clontech). RESULTS:(1) Based on da...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/0955300032000093146
更新日期:2003-05-01 00:00:00
abstract::Eelpout (Zoarces viviparus), a marine fish, were exposed to gamma-radiation at a dose-rate of 2.0 mGy h-1. They were injected with the antigen trinitrophenyl-keyhole limpet haemocyanin (TNP-KLH) and their specific humoral immune response to the TNP hapten measured. There were no differences in the primary antibody res...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553009514550091
更新日期:1995-01-01 00:00:00
abstract::Pulsed-field electrophoresis is being used extensively in the gene mapping studies and in the analysis of DNA strand breakage by ionizing radiation. We have evaluated the relationship between the fraction of S phase DNA in a cell population and its ability to modify the migration of DNA in pulsed-field gel electrophor...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/095530096145427
更新日期:1996-06-01 00:00:00
abstract:PURPOSE:In case of a large-scale radiation accident when hundreds of people may be exposed, it is important to distinguish the severely exposed individuals (> or =1 gray), who require early medical treatment, from those less exposed. The aim of our study was to develop a quick population triage method based on automate...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553000903264481
更新日期:2010-01-01 00:00:00
abstract::During previous studies on the relationship between thermosensitivity and intracellular pH (pHi) regulation in mammalian cells, we observed that the thermoresistant TR-4 cells appeared to be resistant to manipulations of the Na+/H+ antiport, one of the two primary membrane regulators of pHi. We hypothesized that this ...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/095530096144969
更新日期:1996-10-01 00:00:00
abstract:PURPOSE:Zearalenone is a potent estrogenic metabolite produced by some Fusarium and Gibberella species. Therefore, the aim of this study was to determine the accumulation of Technetium-[99m]-labeled zearalenone in mice organs as well as to study the protective effect of Lactobacillus plantarum. MATERIALS AND METHODS:T...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553002.2019.1524990
更新日期:2018-12-01 00:00:00
abstract:PURPOSE:To investigate whether pre- and post-drug magnetic field (MF) exposure of 50 Hz, 0.2 mT has any significant effect on pentylenetetrazol (PTZ)-induced seizures in mice. MATERIAL AND METHODS:MF was generated by a pair of Helmholtz coils. Seizures were induced by PTZ injection intraperitoneally (i.p.) at a dose o...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553000701206676
更新日期:2007-04-01 00:00:00
abstract::Most estimates of the radiation dose lethal to 50 per cent of a human population are based on historical data taken from well-known experiences reflecting inadequately known physical and biological conditions, or from medical procedures where individual patients received advantages of modern clinical care. It has been...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553008914550481
更新日期:1989-03-01 00:00:00
abstract::Genetic analysis was performed on 72 Italian A-T families ascertained through 91 probands. The frequency of the A-T gene was estimated through Dahlberg's formula, which uses the frequencies of first cousin marriages among the patients' parents and in the general population were obtained from the collection of Catholic...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:
更新日期:1994-12-01 00:00:00
abstract:PURPOSE:We introduce and evaluate a high throughput biodosimetry test system (REDI-Dx) suitable for testing of thousands of potential radiation victims following a mass scale nuclear event caused by detonation of a nuclear device or a nuclear accident, as part of an overall strategy for effective medical management of ...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.1080/09553002.2018.1532615
更新日期:2020-01-01 00:00:00
abstract:PURPOSE:To investigate physical and biophysical properties of proton tracks 1 keV-300 MeV using Monte Carlo track structure methods. MATERIALS AND METHODS:We present model calculations for cross sections and methods for simulations of full-slowing-down proton tracks. Protons and electrons were followed interaction-by-...
journal_title:International journal of radiation biology
pub_type: 杂志文章
doi:10.3109/09553002.2010.518204
更新日期:2011-02-01 00:00:00