Abstract：
:The reactions of free and DNA-bound 2,2,5,5-tetramethylpyrrolidine-N-oxyl (PROXYL) probes with radicals generated during radiolysis of dilute aqueous solutions of DNA were examined. For the free PROXYL probe in deaerated solution with each of the four nucleotides (dAMP, dCMP, dGMP, and TMP) it was found that the pyrimidine radicals were more reactive toward the probe than were the purine radicals. Reactions of the electron adduct of TMP and the hydroxyl radical adducts of dAMP, dGMP, and TMP with the probe resulted in little or no reduction of the probe. For TMP these results are consistent with the fact that both the protonated electron and hydroxyl radical adducts of TMP will covalently bind to the nitroxide function of the probe. Reduction of the PROXYL probe was observed in reactions with the hydroxyl radical adduct of dCMP and with the electron adducts of dAMP, dCMP, and dGMP. Results of the radiolysis of the free PROXYL probe in deaerated dilute solution of DNA suggest that the PROXYL probe protects the DNA from water radical attack as the ratio of DNA bases to PROXYL probe increases above 50:1. Reactions of DNA-bound probes are dependent on the depth of the nitroxide function in relation to the major groove of the DNA helix. Two probes with tether lengths which are less than the depth of the major groove show an expected increase in reactions with DNA base radicals as compared to a probe with a tether that extends beyond the groove. The longer probe is involved largely in reactions with sugar and water radicals along the periphery of the DNA helix. In the presence of oxygen, there is a dramatic decrease in the loss of both the free and DNA-bound probes due to the lack of reaction of these probes with peroxyl radicals formed by the addition of molecular oxygen to DNA radicals.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Swarts SG,Sevilla MDsubject
Has Abstractpub_date
1987-10-01 00:00:00pages
21-35issue
1eissn
0033-7587issn
1938-5404journal_volume
112pub_type
杂志文章abstract：:There is a need for minimally invasive biomarkers that can accurately and quickly quantify radiation exposure. Radiation-responsive proteins have applications in clinical medicine and for mass population screenings after a nuclear or radiological incident where the level of radiation exposure and exposure pattern comp...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13927.1
更新日期：2015-07-01 00:00:00
abstract：:Three somatic mutation assays were evaluated in men exposed to low-dose, whole-body, ionizing radiation. Blood samples were obtained between 1992 and 1999 from 625 Russian Chernobyl cleanup workers and 182 Russian controls. The assays were chromosome translocations in lymphocytes detected by FISH, hypoxanthine phospho...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2002)158[0424:tsgbac]2.0.co;2
更新日期：2002-10-01 00:00:00
abstract：:The induction of thymic lymphomas by whole-body X irradiation with four doses of 1.8 Gy (total dose: 7.2 Gy) in C57BL/6 mice was suppressed from a high frequency (90%) to 63% by preirradiation with 0.075 Gy X rays given 6 h before each 1.8-Gy irradiation. This level was further suppressed to 43% by continuous whole-bo...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3289
更新日期：2005-02-01 00:00:00
abstract：:Phosphorylated ATM immunofluorescence staining was used to investigate the dose-response relationship for the number of DNA double-strand breaks (DSBs) induced in primary normal human fibroblasts irradiated with doses from 1.2 to 200 mGy. The induction of DSBs showed a supralinear dose-response relationship. Radiation...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1255.1
更新日期：2008-09-01 00:00:00
abstract：:A standardized dichlorofluorescin (DCF) fluorometric assay capable of measuring radiation-induced oxidative stress was used to determine the effectiveness of protons and high-mass, high-atomic number (Z) and high-energy (HZE) particles to produce oxidative stress in vitro. Protons were found to be about equally as eff...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2005)163[0364:doosib]2.0.co;2
更新日期：2005-04-01 00:00:00
abstract：:We investigated delayed reproductive death and chromosome bridge formation in mitotic cells in colonies of normal human embryonic cells which survived exposure to 6 Gy of X rays. Eighteen primary clones each derived from control and irradiated cultures were isolated and secondary colonies were grown up. Six of the pri...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-10-01 00:00:00
abstract：:Blockers of the renin-angiotensin-aldosterone system (RAAS) ameliorate cognitive deficits and some aspects of brain injury after whole-brain irradiation. We investigated whether treatment with the angiotensin II type 1 receptor antagonist L-158,809 at a dose that protects cognitive function after fractionated whole-br...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2560.1
更新日期：2011-07-01 00:00:00
abstract：:Activation of the transcription factor nuclear factor-kappaB (NF-kappaB) is one of the important responses of cells to an external stress such as ionizing radiation. We studied radiation-induced NF-kappaB activation in vivo in male BALB/c mice. After the mice were exposed to 8.5 Gy total-body gamma irradiation, the sp...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-06-01 00:00:00
abstract：:This laboratory previously demonstrated that hyperbaric oxygen and hyperbaric carbogen improved oxygenation in the R3230Ac tumor, but normobaric 100% O2 and carbogen did not. The current study assessed tumor growth after exposure to radiation plus either hyperbaric oxygen, carbogen or carbogen/nicotinamide and the rel...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-06-01 00:00:00
abstract：:Dose-response relationships observed in laboratory animals can be used to identify possible human risk factors and may also be used in a quantitative manner when human data are not available. This paper presents an analysis of the dose dependency of osteosarcoma incidence in beagle dogs given a single inhalation expos...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-10-01 00:00:00
abstract：:The distribution and kinetics of proximal tubular cells with abnormally large nuclei, which were observed in irradiated mouse kidneys before any other obvious histological effects, were investigated. Six months after the administration of 13 or 15 Gy, little histopathological change was noted, in the kidneys of C3H mi...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：:Vascular injury after radiation exposure contributes to multiple types of tissue injury through a cascade of events. Some of the earliest consequences of radiation damage include increased vascular permeability and promotion of inflammation, which is partially manifested by increased leukocyte-endothelial (L/E) intera...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14896.1
更新日期：2018-07-01 00:00:00
abstract：:Electron microbeam experiments are planned or under way to explore in part the question regarding whether the bystander effect is a general phenomenon or is restricted to high-LET radiation. Since low-LET radiations scatter more readily compared to high-LET radiations, identifying bystander cells and assessing the pot...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2001)155[0089:moakem]2.0.co;2
更新日期：2001-01-01 00:00:00
abstract：:The relationships between DNA damage and the survival of murine bone marrow cells irradiated in situ were examined. Cell survival was assayed by the ability of bone marrow cells from irradiated mice to form colonies in vitro (CFU-C). DNA double-strand breaks (DSBs) were measured by neutral (nondenaturing) filter eluti...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
abstract：:Cytoglobin is a recently identified vertebrate globin whose functions include scavenging reactive oxygen and nitrosative species. In tumor cells, CYGB may function as a tumor suppressor gene. Here we show that knockdown of cytoglobin expression can sensitize human glioma cells to oxidative stress induced by chemical i...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2517.1
更新日期：2011-08-01 00:00:00
abstract：:Molecular imaging is an evolving science that is concerned with the development of novel imaging probes and biomarkers that can be used to non-invasively image molecular and cellular processes. This special issue approaches molecular imaging in the context of radiation research, focusing on biomarkers and imaging meth...
journal_title：Radiation research
pub_type：
doi：10.1667/rr2959.1
更新日期：2012-04-01 00:00:00
abstract：:Proton exposure induces mutations and cancer, which are presumably linked. Because protons are abundant in the space environment and significant uncertainties exist for the effects of space travel on human health, the purpose of this study was to identify the types of mutations induced by exposure of mammalian cells t...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR3174.1
更新日期：2013-05-01 00:00:00
abstract：:Tumor radiotherapy with large-field irradiation results in an increase of p53-dependent apoptosis of the radiosensitive hematopoietic stem cells. Proapoptotic PUMA is a transcriptional target of p53. Thus suppression of PUMA expression by gene therapy with the transcription repressor SNAI2 as transgene might be a pote...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1952.1
更新日期：2010-05-01 00:00:00
abstract：:Water:n-octanol partition coefficients (KD) were determined for a series of radioprotective thiols to ascertain whether these could be used to estimate reliably their rates of uptake into mammalian cells by passive diffusion. Values of KD determined for thiols in 0.1 M potassium phosphate, pH 7.4, at 22 degrees C were...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1996-08-01 00:00:00
abstract：:To study the dynamics of protein recruitment to DNA lesions, ion beams can be used to generate extremely localized DNA damage within restricted regions of the nuclei. This inhomogeneous spatial distribution of lesions can be visualized indirectly and rapidly in the form of radiation-induced foci using immunocytochemic...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3374
更新日期：2005-06-01 00:00:00
abstract：:Understanding the cognitive and behavioral consequences of brain exposures to low-dose ionizing radiation has broad relevance for health risks from medical radiation diagnostic procedures, radiotherapy and environmental nuclear contamination as well as for Earth-orbit and space missions. Analyses of transcriptome prof...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1389.1
更新日期：2009-01-01 00:00:00
abstract：:The neon beam at 250 MeV/nucleon from the Bevalac at the Lawrence Berkeley Laboratory is bombarded in nuclear emulsion. The experimental interaction cross section of the neon beam in emulsion is 1078 +/- 35 mb, in agreement with the calculations from the modified Bradt and Peters formula. The secondary fragments were ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-09-01 00:00:00
abstract：:Therapeutic irradiation of the brain can cause a progressive cognitive dysfunction that may involve defects in neurogenesis. In an effort to understand the mechanisms underlying radiation-induced stem cell dysfunction, neural precursor cells isolated from the adult rat hippocampus were analyzed for acute (0-24 h) and ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3112
更新日期：2004-01-01 00:00:00
abstract：:The late effects of heavy-ion irradiation on the spinal cord of the rat were investigated histologically and morphometrically. After a single exposure of each animal's lower thoracic and lumbar spinal cord to a carbon-ion beam, the animals were observed clinically for up to 69 weeks and their spinal cords were examine...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-09-01 00:00:00
abstract：:Radiation is an independent risk factor for cardiovascular and cerebrovascular disease in cancer patients. Modern radiotherapy techniques reduce the volume of the heart and major coronary vessels exposed to high doses, but some exposure is often unavoidable. Radiation damage to the myocardium is caused primarily by in...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR1862.1
更新日期：2010-12-01 00:00:00
abstract：:Ketogenic diets are low in carbohydrates and high in fat, which forces cells to rely more heavily upon mitochondrial oxidation of fatty acids for energy. Relative to normal cells, cancer cells are believed to exist under a condition of chronic mitochondrial oxidative stress that is compensated for by increases in gluc...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14668.1
更新日期：2017-06-01 00:00:00
abstract：:Whether inner-shell ionizations of DNA atoms, called core ionizations, are critical events for cell inactivation by ionizing radiations such as 100 keV electrons and gamma rays has been investigated. The number of core ionizations in DNA atoms per gray of the two types of radiations is calculated from various Monte Ca...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0451.1
更新日期：2007-04-01 00:00:00
abstract：:Radiation exposure leads to a risk for long-term deterministic and stochastic late effects. Two individuals exposed to protracted photon radiation in the radiological accident at the Lilo Military site in Georgia in 1997 received follow-up treatment and resection of several chronic radiation ulcers in the Bundeswehr H...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0774.1
更新日期：2007-05-01 00:00:00
abstract：:Incorporation of bromodeoxyuridine (BrdU) into DNA in both Chinese hamster ovary (CHO) cells and human melanoma (U1) cells reduced the rate of DNA migration in transverse alternating-field electrophoresis (TAFE) agarose gel optimized for separating molecules larger than 2 Mb. This "BrdU migration effect" was independe...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-04-01 00:00:00
abstract：:Monte Carlo simulations are used in the development of a nanotechnology-based multi-pixel beam array small animal microirradiation system. The microirradiation system uses carbon nanotube field emission technology to generate arrays of individually controllable X-ray pixel beams that electronically form irregular irra...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1453.1
更新日期：2009-03-01 00:00:00
