Abstract：
:In higher eukaryotes, DNA double-strand breaks (DSBs) induced by ionizing radiation activate checkpoints that delay progression through the cell cycle. Compared to delays in other phases of the cell cycle, delays induced in G(2) are longer and frequently correlate with resistance to killing by radiation. Therefore, modulation of the G(2) checkpoint offers a means to modulate cellular radiosensitivity. Although compounds are known that reduce the G(2) checkpoint and act as radiosensitizers, compounds enhancing this checkpoint have not been reported. Here we summarize evidence for a factor with such properties. We show that a highly radioresistant rat embryo fibroblast (REF) cell line displays a strong G(2) checkpoint partly as a result of a factor excreted into the growth medium by nonirradiated cells. Various tests indicate that this G(2)-arrest modulating activity (GAMA) is a small molecule showing detectable retention only after passing through filters with a molecular weight cutoff limit of less than 1,000 Da. GAMA is heat stable and resistant to treatment with proteases or nucleases. Electroelution tests show that GAMA is uncharged at neutral pH, a result that is in agreement with the observed failure to bind S- or Q-Sepharose. Investigations on the mechanism of GAMA function indicate ligand-receptor interactions and allow the classification of cells as producers, responders or both. Compounds with properties such as those of GAMA bridge intercellular communication with the DNA damage response and may function as radioprotectors.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Fan X,Cheong N,Iliakis Gdoi
10.1667/RR2165.1subject
Has Abstractpub_date
2010-10-01 00:00:00pages
424-35issue
4eissn
0033-7587issn
1938-5404journal_volume
174pub_type
杂志文章abstract：:It is commonly accepted that ionizing radiation induces genomic instability by changes in genomic structure, epigenetic regulation and gene expression. Human endogenous retroviruses (HERV)-R also are often differentially expressed between normal and disease tissues under unstable genomic conditions and are implicated ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2888.1
更新日期：2012-11-01 00:00:00
abstract：:The physical and biological basis of our model to calculate the biological effects of charged particles, termed the local effect model (LEM), has recently been questioned in a commentary by R. Katz. Major objections were related to the definition of the target size and the use of the term cross section. Here we show t...
journal_title：Radiation research
pub_type： 评论,杂志文章
doi：10.1667/rr3174
更新日期：2004-05-01 00:00:00
abstract：:We investigated the effect of irradiation on the kinetic characteristics of amino acid and glucose transport, and the effect on the activity of the cell membrane-bound enzyme 5'-nucleotidase and on the receptor-mediated stimulation of cyclic adenosine monophosphate synthesis by prostaglandin E1. Irradiation inhibited ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-12-01 00:00:00
abstract：:To determine whether comparative proteomics could detect differential protein expression after lung irradiation in two mouse strains with different radiation responses, lung proteins were subjected to two-dimensional orthogonal liquid-phase separations, with chromatofocusing in the first dimension and nonporous silica...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1173.1
更新日期：2008-04-01 00:00:00
abstract：:The nature of the primary biochemical defect in the human radiosensitive and cancer-prone syndrome, ataxia telangiectasia (AT), has remained obscure despite many efforts to elucidate it. In this study, AT complementation group D cells and a nearly isogenic corrected AT-hamster hybrid derivative have been analyzed for ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-12-01 00:00:00
abstract：:Hypoadrenocorticism, known as Addison's disease in humans, was diagnosed in six beagles after inhalation of at least 1.7 kBq/g lung of 238PuO2. Histological examination of adrenal gland specimens obtained at necropsy revealed marked adrenal cortical atrophy in all cases. Autoradiographs showed only slight alpha-partic...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1996-12-01 00:00:00
abstract：:Inhalation and ingestion of 137Cs and other long-lived radionuclides can occur after large-scale accidental or malicious radioactive contamination incidents, resulting in a complex temporal pattern of radiation dose/dose rate, influenced by radionuclide pharmacokinetics and chemical properties. High-throughput radiati...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RADE-20-00042.1
更新日期：2020-10-16 00:00:00
abstract：:Both plant senescence and plant response to ionizing radiation involve changes in gene expression and epigenetic profiles, that rely on the formation of reactive oxygen species. However, how the developmental stage of a plant affects its response to ionizing radiation has not been extensively studied. In this study, o...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13840.1
更新日期：2015-02-01 00:00:00
abstract：:The (11)B(p,alpha)(8)Be* nuclear reaction was assessed for its ability to quantitatively map the in vivo subcellular distribution of boron within gliosarcomas treated with a boronated neutron capture therapy agent. Intracranial 9L gliosarcomas were produced in Fischer 344 rats. Fourteen days later, the majority of the...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3085
更新日期：2003-12-01 00:00:00
abstract：:Wen, B., Urano, M., Humm, J. L., Seshan, V. E., Li, G. C. and Ling, C. C. Comparison of Helzel and OxyLite Systems in the Measurements of Tumor Partial Oxygen Pressure (pO(2)). Radiat. Res. 168, 67-75 (2008). It has been demonstrated in both experimental and human malignancies that hypoxic tumor cells are linked with ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0888.1
更新日期：2008-01-01 00:00:00
abstract：:The first hundred years of radiation studies have greatly clarified the chemical processes that are induced by radiation. While the fundamental ionization processes are similar in all systems, properties of the medium such as phase, polarity and composition can greatly affect the chemistry. In all systems, one needs t...
journal_title：Radiation research
pub_type： 历史文章,杂志文章
doi：
更新日期：1995-11-01 00:00:00
abstract：:The radiosensitivity of cultured HeLa cells was increased upon depletion of the natural cellular polyamines putrescine, spermidine and spermine through treatment of cultures with inhibitors of polyamine biosynthesis. This increased radiosensitivity was manifested as a decrease in the D0 and by the absence of a shoulde...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-01-01 00:00:00
abstract：:Cellular nonprotein thiols (NPSH) consist of glutathione (GSH) and other low molecular weight species such as cysteine, cysteamine, and coenzyme A. GSH is usually less than the total cellular NPSH, and with thiol reactive agents, such as diethyl maleate (DEM), its rate of depletion is in part dependent upon the cellul...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-09-01 00:00:00
abstract：:Here we report that suramin sensitizes LM217, MDA-MB-468, T98G and A431 cells to ionizing radiation. Suramin sensitized cells to X radiation in a dose-dependent fashion, and longer exposure to suramin before X irradiation resulted in more efficient sensitization. The dose-modifying factors calculated from the survival...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3217
更新日期：2004-09-01 00:00:00
abstract：:A recent publication by Leith et al. (Cancer Res. 51, 4111-4113, 1991) showed that administration of epidermal growth factor (EGF) (0.25 mg/kg; q.i.d. x 7) to mice bearing xenografted A431 human epidermoid cancers produced increased tumor growth and a reduction of the percentage of hypoxic cells within neoplasms. In c...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：:Evaluation of the probability of biological phenomena per cell by colony formation, requires knowledge not only of the number of cells at risk but also of their microdistribution. In the present study, the influence of cellular multiplicity (number of cells per potential colony-forming unit) on the determination of ra...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
abstract：:The relative biological effectiveness was determined using sex-linked recessive lethals induced in Drosophila spermatozoa as the biological effect. The sex-linked recessive lethal test, a measure of mutations induced in germ cells and transmitted through successive generations, yields a linear dose-response curve in t...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
abstract：:Extension of previous investigations at this laboratory regarding life shortening and tumor induction in the mouse has provided more complete dose-response information in the low dose region of X rays and neutrons. A complete observation of survival and late pathology has been carried out on over 2000 BC3F1 female mic...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-02-01 00:00:00
abstract：:Previous studies identified radiation therapy as a key modifier of basal cell carcinoma (BCC) risk in survivors of hematopoietic cell transplantation (HCT). In the present analysis, risk of BCC was analyzed in relation to age at transplant, attained age, race, total-body irradiation (TBI), and radiation fractionation ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1469.1
更新日期：2009-02-01 00:00:00
abstract：:At the outset of the accident at Fukushima Daiichi Nuclear Power Plant in March 2011, the radiation doses experienced by residents were calculated from the readings at monitoring posts, with several assumptions being made from the point of view of protection and safety. However, health effects should also be estimated...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13351.1
更新日期：2013-11-01 00:00:00
abstract：:The structural maintenance of chromosome 1 (Smc1) protein is a member of the highly conserved cohesin complex and is involved in sister chromatid cohesion. In response to ionizing radiation, Smc1 is phosphorylated at two sites, Ser-957 and Ser-966, and these phosphorylation events are dependent on the ATM protein kina...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2402.1
更新日期：2011-03-01 00:00:00
abstract：:The space environment consists of a varying field of radiation particles including high-energy ions, with spacecraft shielding material providing the major protection to astronauts from harmful exposure. Unlike low-LEpsilonTau gamma or X rays, the presence of shielding does not always reduce the radiation risks for en...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR0535.1
更新日期：2006-10-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1483.1
更新日期：2009-08-01 00:00:00
abstract：:The primary risk factors of multiple myeloma are age, race and sex, but several studies have found an association between radiological hazards and multiple myeloma. The purpose of this nested case-control study was to investigate whether workers with chronic low-level exposure to internally deposited uranium at the Oa...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1607.1
更新日期：2009-06-01 00:00:00
abstract：:Rat females were exposed to a single 4.0-Gy gamma-ray dose and treated postradiation with a mixture of ATP-AET-mexamine at daily doses of 24, 12, and 3 mg/kg body wt, respectively, in drinking water throughout the period of their survival. With the radiation dose used, life shortening appeared primarily attributable t...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-01-01 00:00:00
abstract：:Peroxidation of unconjugated polyunsaturated fatty acids such as linolenic acid proceeds through a free radical chain mechanism and is accompanied by the formation of conjugated dienes such as hydroperoxides. In an investigation of radiation-induced oxidation of aqueous linolenate, we have measured two indexes of pero...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)153[0201:eotfod]2.0.co;2
更新日期：2000-02-01 00:00:00
abstract：:In the analysis of the effects of radiation or drugs on clonogenic survival data of mammalian cells, it is often advantageous to compare entire dose-response curves generated under different experimental conditions rather than to conduct single-dose comparisons. We propose a two-stage method for the global comparison ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1993-08-01 00:00:00
abstract：:Aqueous solutions of calf thymus deoxyribonucleic acid (DNA) were exposed to hydrogen peroxide in the presence of air. Base products formed in DNA were identified and quantitated following acid hydrolysis and trimethylsilylation using gas chromatography-mass spectrometry. The yields of these products were dependent up...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:The effect of age at exposure on induction of mammary carcinoma was studied in female rats of the inbred WAG/Rij strain that were treated with estrogen. Groups of 40 animals were exposed to a single total-body dose of 1 or 2 Gy of 137Cs gamma radiation at age 8, 10, 12, 15, 22, 36 or 64 weeks. Hormone levels in the an...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-10-01 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
