Abstract：
:Hypoxic BP-8 murine sarcoma cells were exposed to misonidazole and/or radiation and the kinetics and extent of cell death were evaluated with the [125I]iododeoxyuridine-prelabeling assay. Cell death after treatment with lethal doses of misonidazole was rapid and essentially complete within 2 or 3 days after drug exposure. In contrast, radiation death became apparent only after a delay period of 4 days and was complete by Day 10 after irradiation. Radiosensitization by short exposures to sublethal doses of misonidazole affected only the delayed component of cell death, that is, the radiation component of death. In experiments involving sequential radiation and drug treatment, prior irradiation of cells did not enhance the direct cytocidal effects of misonidazole, as evidenced by the fact that the early component of cell death was equal in control and preirradiated cells. However, postirradiation treatment with misonidazole did enhance the delayed radiation component of cell death. These results suggest that radiosensitization and direct killing by misonidazole are two distinct phenomena mediated by different cellular mechanisms, and radiosensitization by misonidazole represents a two-component effect composed of true dose modification and dose additive damage interactions, but these additive effects must occur at a site different from the cellular structure responsible for direct drug-induced cell death.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Hofer KG,Friedland JL,Dynlacht J,Hofer MGsubject
Has Abstractpub_date
1987-07-01 00:00:00pages
130-42issue
1eissn
0033-7587issn
1938-5404journal_volume
111pub_type
杂志文章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：:The effect of heat exposure on the repair of radiation-induced DNA damage which inhibits the ability of nuclear DNA to undergo supercoiling changes was studied using the fluorescent halo assay in thermotolerant and nonthermotolerant (normal) cells. The assay utilizes an intercalating, fluorescent dye to unwind and rew...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-10-01 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：:To determine whether different agents that enhance the expression of potentially lethal X-ray damage (PLD) interact with the same or different lesions (or spectrum of lesions), cell killing was measured in three kinds of experiments: (1) When cells were irradiated in G1 phase and treated with caffeine or hydroxyurea a...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-11-01 00:00:00
abstract：:We have used Escherichia coli B/r to test the proposal that hydroxyl radicals (.OH) are major contributors to lethal damage when bacteria in equilibrium with air or 100% nitrogen are exposed to ionizing radiation. In addition, we have tested the hypothesis that oxygen sensitizes bacterial cells to radiation by reactin...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-02-01 00:00:00
abstract：:An understanding of proton radiobiology is critical for optimization of both proton radiotherapy and assessment of carcinogenesis risk from space radiation. Although the physical aspects of proton beam radiobiology is well understood, the biological aspects, particularly the complex biological end points, have been un...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR2839.1
更新日期：2013-03-01 00:00:00
abstract：:The radiation dose received by crew members in interplanetary space is influenced by the stage of the solar cycle. Using the recently developed models of the galactic cosmic radiation (GCR) environment and the energy-dependent radiation transport code, we have calculated the dose at 0 and 5 cm water depth; using a com...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-05-01 00:00:00
abstract：:As part of a long-term study of the effects of irradiation during development, prenatal and early neonatal mortality were evaluated for beagles exposed in utero at 8 days postcoitus (dpc), 28 dpc, 55 dpc, or 2 days postpartum. Mean doses used were 0,0.16, or 0.83 Gy. A decrease in whelping rates was observed for femal...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：:Low doses of ionizing radiation to cells and animals may induce adaptive responses that reduce the risk of cancer. However, there are upper dose thresholds above which these protective adaptive responses do not occur. We have now tested the hypothesis that there are similar lower dose thresholds that must be exceeded ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1414.1
更新日期：2008-12-01 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 event of a radiation accident or attack, it will be imperative to quickly assess the amount of radiation exposure to accurately triage victims for appropriate care. RNA-based radiation dosimetry assays offer the potential to rapidly screen thousands of individuals in an efficient and cost-effective manner. Howe...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr1977.1
更新日期：2011-02-01 00:00:00
abstract：:We collected initial quantitative information on the effects of high-dose carbon (12C) ions compared to photons on vascular damage in anaplastic rat prostate tumors, with the goal of elucidating differences in response to high-LET radiation, using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Syngene...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15459.1
更新日期：2020-01-01 00:00:00
abstract：:The induction of intracellular DNA strand breaks by X rays and various heavy charged particles was measured by the alkaline unwinding and alkaline and neutral filter elution techniques. No variations in strand break induction were found between the different cell lines under investigation. For a given particle, both t...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1993-07-01 00:00:00
abstract：:Chinese hamster ovary (CHO) cells became thermotolerant after treatment with either heat for 10 min at 45.5 degrees C or incubation in 100 microM sodium arsenite for 1 h at 37 degrees C. Thermotolerance was tested using heat treatment at 45 degrees C or 43 degrees C administered 6-12 h after the inducing agent. At 45 ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:To characterize the differences in the radiosensitivity of individual populations of human hematopoietic stem/progenitor cells (HSPCs), we examined the relationship among cell surface antigens, clonogenic potential and radiation survival. The expressions of CD34, CD38, CD45RA, CD110 and Tie-2, early differentiation pa...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1839.1
更新日期：2010-02-01 00:00:00
abstract：:To investigate the effects of ionizing radiation on an isolated neuronal network without complicating systemic factors, slices of hippocampus from the guinea pig were isolated and studied in vitro. Slices were irradiated with a 60Co source and compared to paired, sham-irradiated controls. Electrophysiological activity...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-12-01 00:00:00
abstract：:Existence of a substantial fraction of replicon initiation events refractory to the effects of X irradiation in Chinese hamster cells has been reported by several laboratories. The work reported here examined whether this apparently refractive fraction resulted from a delayed inhibition of initiation events. Data obta...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-11-01 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：:The well-established process of potentially lethal damage (PLD) repair enhances plateau-phase cell survival after exposure to ionizing radiation. PLD repair requires that confluent cells be incubated prior to plating for a colony-forming assay rather than being plated immediately. Enhanced double-strand break (DSB) re...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr1423.1
更新日期：2008-10-01 00:00:00
abstract：:A significant fraction of DNA damage produced by ionizing radiation comes from free radicals generated during the radiolysis of water, that is, by indirect effects. The hydroxyl radical, the principal damaging species, produces single-strand breaks and a plethora of base and sugar lesions that can be cytotoxic or muta...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：
更新日期：1998-11-01 00:00:00
abstract：:Long-term retention of 133Ba in the trachea from intratracheally administered BaSO4 particles was determined by both serial sacrifice and external scanning methods up to 6 months after injection. The amount of 133Ba retained 1 week after injection in the caudal region of the trachea, where the tip of the cannula had b...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-06-01 00:00:00
abstract：:Mixed radiation fields comprise the most common form of radiation exposure. Given their relevance in radiation protection, cancer radiotherapy and space research, accurate predictions of the corresponding radiation effects are essential. The local effect model (LEM) allows the prediction of cell survival after ion irr...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15456.1
更新日期：2020-02-01 00:00:00
abstract：:Pepleomycin is a derivative of bleomycin, which is less toxic to the host but possesses greater antitumor activity. Experiments are described here in which Chinese hamster V-79 cells in culture and a murine squamous cell carcinoma in vivo have been used to obtain survival curves for pepleomycin alone or in combination...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-05-01 00:00:00
abstract：:The exposure of peripheral blood mononuclear cells (PBMCs) was performed in a 10-T static magnetic field. Without lymphocyte stimulation, there were no significant differences in the viability of the exposed and unexposed CD4(+) T cells, CD8(+) T cells, B cells, and natural killer (NK) cells. The expression of Th1 typ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2003)159[0775:eotsmf]2.0.co;2
更新日期：2003-06-01 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：:Trypanothione is a unique diglutathionyl-spermidine conjugate found in abundance in trypanosomes but not in other eukaryotes. Because trypanothione is a naturally occurring polyamine thiol reminiscent of the synthetic drug amifostine, it may be a useful protector against radiation and oxidative stress. For these reaso...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2235.1
更新日期：2010-09-01 00:00:00
abstract：:In this study, we investigated the accuracy of using off-line bioluminescence imaging (BLI) and tomography (BLT) to guide irradiation of small soft tissue targets on a small animal radiation research platform (SARRP) with on-board cone beam CT (CBCT) capability. A small glass bulb containing BL cells was implanted as ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2999.1
更新日期：2013-02-22 00:00:00
abstract：:The effect of ionizing radiation (137Cs) on processing and transport of ribosomal RNA (rRNA) was studied by pulse-labeling HeLa S3 cells with [3H]uridine immediately prior to irradiation. This approach permits kinetic analysis of processing of 45 S rRNA (radiolabeled predominantly prior to irradiation) into its 28 S a...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-01-01 00:00:00
abstract：:Pentamidine is similar to rhodamine-123 in chemical structure and state of electron charge, and rhodamine-123 was previously shown to be a hyperthermic sensitizer under appropriate cell culture conditions. The present experiments were carried out to determine whether pentamidine would potentiate hyperthermic cell kill...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-11-01 00:00:00
abstract：:The efficacy of photodynamic therapy is dependent upon the optical dose rate or upon the fractionation schedule on the light. These effects are thought to be limited by the time required for oxygen diffusion from the capillaries, since this therapy can consume oxygen faster than it can be supplied to tissues distant f...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.2307/3579621
更新日期：1997-05-01 00:00:00
