Abstract：
:The effects of reoxygenation on repair of potentially lethal radiation damage were investigated using MG-63 human osteosarcoma cells in vitro. When exponentially growing MG-63 cells were cultured under hypoxic conditions for 24 h, cells stopped growing and remained at a low density. The hypoxic cells were then reoxygenated by exposure to air and irradiated with a single dose of 3 Gy X rays. The fraction of the reoxygenated cells surviving after 3 Gy increased by a factor of 20.6 when the colony assay was delayed for 24 h. In control cells which were cultured under aerobic conditions before receiving a single dose of 3 Gy, the surviving fraction increased by a factor of 2.5 when the assay was delayed for 24 h. The difference in the magnitude of the repair observed between reoxygenated and aerobic cells was less prominent in confluent cells plated at high density. The enhanced repair after reoxygenation was due mainly to a decrease in the alpha coefficient when the dose-survival curve was fitted to the linear-quadratic model, whereas the most significant change in the fit of the dose-survival curve for the aerobic cells was a decrease in the beta coefficient. The control aerobic cells accumulated at G2/M phase after irradiation, whereas the reoxygenated cells did not show such an accumulation. When the hypoxic cells were irradiated and then reoxygenated, repair of these cells irradiated under hypoxic conditions was also enhanced. This is the first report to show that reoxygenation could increase cell survival after tumor irradiation.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Iizuka M,Ando K,Aruga T,Furusawa Y,Itsukaichi H,Fukutsu K,Nagasawa H,Moriya Hsubject
Has Abstractpub_date
1997-02-01 00:00:00pages
179-84issue
2eissn
0033-7587issn
1938-5404journal_volume
147pub_type
杂志文章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：:The study design and obtained results represent an intercomparison of various laboratories performing dose assessment using the dicentric chromosome analysis (DCA) as a diagnostic triage tool for individual radiation dose assessment. Homogenously X-irradiated (240 kVp, 1 Gy/min) blood samples for establishing calibrat...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR3235.1
更新日期：2013-08-01 00:00:00
abstract：:The electroporation of restriction enzymes into mammalian cells results in DNA double-strand breaks that can lead to chromosome aberrations. Four chemicals known to interfere with cellular responses to DNA damage were investigated for their effects on chromosome aberrations induced by AluI and Sau3AI; in addition, the...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-01-01 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：: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：:Experimentally derived optical constants and X-ray attenuation cross sections were used to construct the complete dipole oscillator strength distribution for solid, dry DNA. Monte Carlo simulations of the energy loss by electrons of initial energy 5 keV to 1 MeV in DNA were performed using cumulative inelastic cross s...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-02-01 00:00:00
abstract：:This paper evaluates the global vitamin D effective UV (UV(vitd)) irradiances under cloudy conditions at a subtropical, southern hemisphere site. The UV(vitd) irradiances were analyzed on a horizontal plane and sampled at 5-min intervals over 18 months so that a wide range of parameters including cloud conditions, sol...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1936.1
更新日期：2010-05-01 00:00:00
abstract：:The percentage of T lymphocytes of atomic bomb survivors showed no change as a function of age or exposure dose. The percentage of T cells was slightly lower in malignant-tumor patients than in the control group, but was significantly higher in the group with chromosomal aberrations than in the control group. The perc...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
abstract：:This study investigated the biological effects and adaptive responses induced by single and repeated in vivo computed tomography (CT) scans. We postulated that, through the induction of low-level oxidative stress, repeated low-dose CT scans (20 mGy, 2 days/week, 10 weeks) could protect mice (C57BL/6) from acute effect...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2532.1
更新日期：2012-02-01 00:00:00
abstract：:There is an ongoing and significant need for radiation countermeasures to reduce morbidities and mortalities associated with exposure of the heart and lungs from a radiological or nuclear incidents. Radiation-induced late effects occur months to years after exposure, stemming from significant tissue damage and remodel...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14403.2
更新日期：2016-11-01 00:00:00
abstract：:To approach treatment of micrometastases of steroid receptor-rich cancers using estrogen receptor-directed therapy with Auger electrons, multicellular spheroids of the estrogen receptor-rich human breast cancer cell line, MCF-7, were prepared and exposed to a range of concentrations of an Auger electron-emitting estro...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-05-01 00:00:00
abstract：:Ionization generates a large number of secondary low-energy electrons (LEEs) with a most probable energy of approximately 10 eV, which can break DNA bonds by dissociative electron attachment (DEA) and lead to DNA damage. In this study, we investigated radiation damage to dry DNA induced by X rays (1.5 keV) alone on a ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14476.1
更新日期：2016-11-01 00:00:00
abstract：:We have examined in mice the effects of mixed ligand treatments with desferrioxamine B (DFOA), Na3Ca-diethylenetriamine pentaacetic acid (DTPA), and DL-penicillamine (PA) on the retention of a mixture of 95Nb and 144Ce. The results show that 95Nb + 144Ce could be mobilized effectively by simultaneous application of sp...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-10-01 00:00:00
abstract：:Chinese hamster ovary cells were irradiated with 250 kVp X rays and analyzed for the presence of DNA double-strand breaks using either polycarbonate filter elution or pulsed-field agarose gel electrophoresis at neutral pH. Reduction in DNA length detected by filter elution was produced as a nonlinear function of incre...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-12-01 00:00:00
abstract：:Nuclear protein and DNA content of HeLa cells was determined as a function of time following hyperthermia by staining isolated nuclei with two fluorescent dyes: fluorescein isothiocyanate (FITC) for protein content and propidium iodide (PI) for DNA content. Bivariate FITC and PI histograms were obtained by flow cytome...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1986-08-01 00:00:00
abstract：:Asynchronously growing V79 cells were assayed for mutation induction following exposure to hyperthermia either immediately before or after being irradiated with 60Co gamma rays. Hyperthermia exposures consisted of either 43.5 degrees C for 30 min or 45 degrees C for 10 min. Each of these heat treatments resulted in a ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-08-01 00:00:00
abstract：:Soil microorganisms in general and biocontrol agents in particular are very sensitive to UV light. The packaging of biocontrol microorganisms into cellular solids has been developed as a means of reducing loss caused by exposure to environmental UV radiation. The bacterial and fungal biocontrol agents Pantoea agglomer...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3027
更新日期：2003-08-01 00:00:00
abstract：:A computer model that simulates the killing of exponentially growing cells by low-dose-rate radiation is described. The model incorporates cell killing by single-hit damage and double-hit (sublethal) damage, as well as repair of sublethal damage, delay of cell cycle progression, blockage and increased sensitivity of c...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-11-01 00:00:00
abstract：:The concept of curvature in dose-response relationships figures prominently in radiation biology, encompassing a wide range of interests including radiation protection, radiotherapy and fundamental models of radiation action. In this context, the ability to detect even small amounts of curvature becomes important. Sta...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14520.1
更新日期：2017-01-01 00:00:00
abstract：:The International Commission on Radiation Protection (ICRP) has lowered the dose limits for workers and for the general public exposed to ionizing radiation. Consequently, a reliable dosimetric method for monitoring possible radiation-induced damage is of great importance in radioprotection. The counting of dicentric ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR3544.1
更新日期：2006-05-01 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：:Fluorescence in situ hybridization procedures were used to examine the influence of chromosome locus on the frequency and type of chromosome aberrations induced by 60Co gamma rays in the human lymphoblastoid cell line TK6. Aberrations involving the X chromosome were compared to those involving the similarly sized auto...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1994-03-01 00:00:00
abstract：:To accurately quantify the number of single-strand breaks (SSBs) induced in plasmid DNA molecules after irradiation, a new type of assay methodology has been explored. The new method is based on the TUNEL (terminal deoxynucleotide transferase dUTP nick end-labeling) assay that was adopted for use under ELISA (enzyme-l...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1684.1
更新日期：2009-11-01 00:00:00
abstract：:The mutagenic activity of green (532 nm) and infrared (1064 nm) ultra-short laser light pulses was tested in cultured Syrian hamster fibroblasts by a hypoxanthine phosphoribosyl-transferase (HPRT) mutagenesis assay. In 18 irradiation trials, cells were exposed to eight consecutive 100-ps pulses of either 532 nm or 106...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-04-01 00:00:00
abstract：:Female rhesus monkeys received whole-body doses of ionizing radiation in the form of single-energy protons, mixed-energy protons, X rays, and electrons. Endometriosis developed in 53% of the monkeys during a 17-year period after exposure. Incidence rates for endometriosis related to radiation type were: single-energy ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-05-01 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：:Based on murine survival studies, endogenous hemopoietic spleen colony formation (E-CFU), and recovery of bone marrow and splenic granulocyte-macrophage colony-forming cells (GM-CFC), it was demonstrated that the postirradiation administration of glucan, an immunomodulator and hemopoietic stimulant, enhances the radio...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-01-01 00:00:00
abstract：:Human peripheral blood samples collected from three healthy human volunteers were exposed in vitro to pulsed-wave 2450 MHz radiofrequency (RF) radiation for 2 h. The RF radiation was generated with a net forward power of 21 W and transmitted from a standard gain rectangular antenna horn in a vertically downward direct...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)153[0479:pddihb]2.0.co;2
更新日期：2000-04-01 00:00:00
abstract：:To determine the linear energy transfer (LET) dependence of the biological effects of densely ionizing radiation in relation to changes in the ionization density along the track, we measured the yields and spectrum of clustered DNA damages induced by charged particles of different atomic number but similar kinetic ene...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2093.1
更新日期：2010-08-01 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
