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 shoulder in the survival curves. However, our previous studies have shown that the initial yield of X-ray-induced DNA damage did not appear to be elevated in polyamine-depleted cells. In addition, polyamine-depleted cells exhibited markedly altered X-ray-induced changes in the distribution of cells in the phases of the cell cycle characterized by increased time of onset and lengthened duration of G2-phase delay. Addition of polyamines to cultures for short periods prior to irradiation restored normal radioresistance and reversed the anomalous features of the G2-phase delay profile. Polyamine supplementation experiments as well as studies in which combinations of inhibitors were employed to modulate specific polyamine levels suggest that spermidine may play a primary role in governing cellular radioresponsiveness. The radioprotective aminothiol WR-1065 protected normal and polyamine-depleted cells to a proportionately similar extent (protection factor of 2.4 and 2.8, respectively) but had no apparent ability to restore the shoulder or alter the G2-phase delay markedly in polyamine-depleted cells. The findings reported here extend our previous observations that polyamine depletion results in a compromised ability to respond to X irradiation and suggest that a defect in repair and/or the G2-phase delay response may be the determining factors.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Snyder RD,Schroeder KKsubject
Has Abstractpub_date
1994-01-01 00:00:00pages
67-75issue
1eissn
0033-7587issn
1938-5404journal_volume
137pub_type
杂志文章abstract：:The growth of certain UV-radiation-induced tumors is suppressed by T lymphocytes, but it has been proposed that non-T lymphocytes stimulate the growth of several of these tumors. In this study, the indirect effects of X irradiation on the growth of one such tumor in T-cell-deficient nude mice was tested. Even when the...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1996-12-01 00:00:00
abstract：:We previously reported that a priming dose of 0.3 Gy on gestation day 11 significantly increased the rate of living fetuses and reduced the incidence of congenital malformations caused by exposure to 5 Gy X rays on gestation day 12 in ICR mice. In the present study, postnatal development of the live offspring was inve...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-08-01 00:00:00
abstract：:Four programs have been written to enable radiobiologists to build a computer data base of cellular dose-survival data, calculate cell survival with a correction for cell multiplicity at the time of irradiation, fit various survival models to the data by iteratively weighted least squares, and calculate the ratio of s...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-11-01 00:00:00
abstract：:Diethylenetriaminepentaacetic acid (DTPA) is currently still the only known chelating drug that can be used for decorporation of internalized plutonium (Pu) and americium (Am). It is generally assumed that chelation occurs only in biological fluids, thus preventing Pu/Am deposition in target tissues. We postulate that...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14193.1
更新日期：2016-06-01 00:00:00
abstract：:This is the 14th report in a series of periodic general reports on mortality in the Life Span Study (LSS) cohort of atomic bomb survivors followed by the Radiation Effects Research Foundation to investigate the late health effects of the radiation from the atomic bombs. During the period 1950-2003, 58% of the 86,611 L...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2629.1
更新日期：2012-03-01 00:00:00
abstract：:Abstract Double-strand breaks (DSBs) can be generated in the DNA of mammalian cells when heat-labile sites induced by ionizing radiation within a clustered DNA damage site are thermally transformed to single-strand breaks (SSBs) and combine with other SSBs or heat-labile sites in the opposite DNA strand. When this the...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1745.1
更新日期：2009-08-01 00:00:00
abstract：:Normal human fibroblasts in plateau phase ( congruent with 95% G(1) phase) were stained with the vital nuclear dye Hoechst 33342 (blue fluorescence) or the vital cytoplasmic dye Cell Tracker Orange (orange fluorescence) and plated at a ratio of 1:1. Only the blue-fluorescing nuclei were microbeam-irradiated with a def...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3236
更新日期：2004-10-01 00:00:00
abstract：:Dose assessment after radiological disasters is imperative to decrease mortality through rationally directed medical intervention. Our goal was to identify biomarkers capable of qualitative (nonirradiated/irradiated) and/or quantitative (dose) assessment of radiation exposure. Using real-time quantitative PCR, biodosi...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2419.1
更新日期：2011-07-01 00:00:00
abstract：:Dose-response relationships for X-ray-induced reciprocal translocations in spermatogonial stem cells of mutant and wild-type mice were established by spermatocyte analysis many cell generations after irradiation. The mutants studied were Wv/+, the viable allele of dominant spotting in the heterozygous state, and Slcon...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-02-01 00:00:00
abstract：:1. A survival curve for the colony-forming ability of mouse bone marrow cells irradiated in vivo with Co60 gamma-rays has been obtained. The curve may be characterized by D0 of 95 rads and an extrapolation number of 1.5. 2. Comparison with the survival curve obtained for irradiated in vitro indicated a statistically s...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1962-06-01 00:00:00
abstract：:Clustered DNA damage is considered an important factor in determining the biological consequences of ionizing radiation. In this study, we successfully estimated the localization of abasic sites (APs) in DNA exposed to ionizing radiation using fluorescence resonance energy transfer (FRET) without any involvement of re...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13780.1
更新日期：2015-01-01 00:00:00
abstract：:Potentially lethal damage (PLD) repair has been defined as that property conferring the ability of cells to recover from DNA damage depending on the postirradiation environment. Using a novel cyclin dependent kinase 1 inhibitor RO-3306 to arrest cells in the G2 phase of the cell cycle, examined PLD repair in G2 in cul...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13744.1
更新日期：2014-10-01 00:00:00
abstract：:Molecular oxygen has long been recognized as a powerful radiosensitizer that enhances the cell-killing efficiency of ionizing radiation. Radiosensitization by oxygen occurs at very low concentrations with the half-maximum radiosensitization at approximately 3 mmHg. However, robust hypoxia-induced signal transduction c...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR13959.1
更新日期：2015-05-01 00:00:00
abstract：:There is growing scientific, regulatory and public concern over anthropogenic input of radionuclides to the aquatic environment, especially given the issues surrounding existing nuclear waste, future energy demand and past or potential nuclear accidents. A change in the approach to how we protect the environment from ...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/rr2687.1
更新日期：2012-05-01 00:00:00
abstract：:Proteinase-activated receptor 2 (Par2, F2rl1, also designated PAR-2 or PAR2) is prominently expressed in the intestine and has been suggested as a mediator of inflammatory, mitogenic and fibrogenic responses to injury. Mast cell proteinases and pancreatic trypsin, both of which have been shown to affect the intestinal...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3080
更新日期：2003-11-01 00:00:00
abstract：:Ionizing radiation induces bistranded clustered damages--two or more abasic sites, oxidized bases and strand breaks on opposite DNA strands within a few helical turns. Since clusters are refractory to repair and are potential sources of double-strand breaks (DSBs), they are potentially lethal and mutagenic. Although i...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3498.1
更新日期：2006-02-01 00:00:00
abstract：:A subline of a rat mammary carcinoma (MATB 13762), selected for resistance to melphalan, is cross-resistant to other alkylating drugs, to unrelated drugs and to ionizing radiation. The difference in radioresponse between the sensitive wild-type cell line and the melphalan- and radiation-resistant line (MLNr) is relate...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-08-01 00:00:00
abstract：:The analysis of mitotic indices (MI) and chromosome breakages in metaphases of 50-hr lymphocyte cultures exposed to the calcium or zinc chelates of diethylenetriamine pentaacetic acid (DTPA) demonstrated: (1) an 80% reduction in MI in cultures from three women but no reduction in those from two men after in vitro expo...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-07-01 00:00:00
abstract：:The effects of the methylxanthine, caffeine, on heat sensitization was investigated using Chinese hamster ovary (CHO) cells. Caffeine sensitized CHO cells to heat killing by reducing both the shoulder and the slope of the 44 degrees C survival curve. Heating was performed in suspension by addition of cells to preheate...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-09-01 00:00:00
abstract：:A study has been made of methods for rapidly inactivating cells of E. coli at neutral pH to prevent enzymatic, chemical, or physical modification to DNA damaged by irradiation. The radiation was delivered in a fraction of a second using an electron accelerator. Cell inactivation was with ethanol or a solution (CSE) co...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-11-01 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：:This work provides a description of a new interaction, cross-section-based model for radiation-induced cellular inactivation, sublethal damage, DNA repair and cell survival, with the ability to more accurately elucidate different radiation-response phenomena. The principal goal of this work is to describe the damage-i...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RADE-20-00052.1
更新日期：2020-09-16 00:00:00
abstract：:Previous work by our group and others has shown the modulation of human immunodeficiency virus (HIV) promoter or long terminal repeat (LTR) after exposure to neutrons and ultraviolet radiations. Using HeLa cells stably transfected with a construct containing the chloramphenicol acetyl transferase (CAT) gene, the trans...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-10-01 00:00:00
abstract：:The A31-11 mouse BALB/3T3 cell system was adapted for the study of malignant transformation induced by 5.3 MeV alpha particles from a specially constructed 238Pu source. The biologic effects were compared to those of 220 kVp X rays. The alpha-radiation survival curve showed a D0 of 70 rad and a relative biological eff...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-11-01 00:00:00
abstract：:The filter elution technique using nondenaturing conditions is widely used to assay DNA double-strand break (DSB) induction and repair. It has been reported that in the measurement of strand breaks higher rates of elution and of initial rejoining are obtained at pH 9.6 compared to pH 7.2. In the present experiments ne...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-09-01 00:00:00
abstract：:Trp53 heterozygous mice are radiation-sensitive and cancer-prone. Groups of 7-8-week-old female Trp53 heterozygous mice were exposed to 4 Gy of 60Co gamma radiation at high (0.5 Gy/min) or low (0.5 mGy/min) dose rate. Other groups received 10 or 100 mGy at low dose rate 24 h prior to the 4-Gy dose. Tumor frequency and...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3190
更新日期：2004-07-01 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：:Nearly 2% of the male population of Estonia aged 20-39 years were sent to Chernobyl to assist in the cleanup activities after the reactor accident. A cohort of 4,833 cleanup workers was assembled based on multiple and independent sources of information. Information obtained from 3,704 responses to a detailed questionn...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-05-01 00:00:00
abstract：:The potential carcinogenic effects of internally deposited alpha-particle-emitting nuclides, notably plutonium, in the liver in humans are unknown but are of concern in relation to exposures from the nuclear industry. However, patients injected with the radiographic contrast medium Thorotrast are chronically exposed t...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-02-01 00:00:00
abstract：:A plasma membrane-rich fraction has been separated from liver cells and cells of two solid rat tumors. D23 hepatoma and MC7 sarcoma. On the basis of marker enzyme activity the membranes separating at the 31-41% interface on the discontinuous sucrose gradient were enriched 15- to 19-fold. No significant differences in ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-01-01 00:00:00
