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 effects of high-dose radiation (1 Gy, 2 Gy). The micronucleated reticulocyte (MN-RET) count increased linearly after exposure to single CT scans of doses ranging from 20 to 80 mGy (P = 0.033). Ten weeks of repeated CT scans (total dose 400 mGy) produced a slight reduction in spontaneous MN-RET levels relative to levels in sham CT-scanned mice (P = 0.04). Decreases of nearly 10% in γ-H2AX fluorescence levels were observed in the repeated CT-scanned mice after an in vitro challenge dose of 1 Gy (P = 0.017) and 2 Gy (P = 0.026). Spontaneous apoptosis levels (caspase 3 and 7 activation) were also significantly lower in the repeated CT-scanned mice than the sham CT-scanned mice (P < 0.01). In contrast, mice receiving only a single CT scan showed a 19% elevation in apoptosis (P < 0.02) and a 10% increase in γ-H2AX fluorescence levels after a 2-Gy challenge (P < 0.05) relative to sham CT controls. Overall, repeated CT scans seemed to confer resistance to larger doses in mice, whereas mice exposed to single CT scans exhibited transient genotoxicity, enhanced apoptosis, and characteristics of radiation sensitization.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Phan N,De Lisio M,Parise G,Boreham DRdoi
10.1667/rr2532.1subject
Has Abstractpub_date
2012-02-01 00:00:00pages
164-75issue
2eissn
0033-7587issn
1938-5404pii
10.1667/RR2532.1journal_volume
177pub_type
杂志文章abstract：:Human T lymphocytes can be used to determine the frequency and molecular spectrum of somatic cell gene mutations induced by ionizing radiations both in vivo and in vitro. In vitro exposure of these G0 cells to low-LET 137Cs gamma rays results in the induction of HPRT mutations and a predominant molecular spectrum of D...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-11-01 00:00:00
abstract：:The effect of sodium bisulfite, a specific inhibitor of chromatin proteolysis, on radiation damage in rat thymocytes in vitro was examined. Rat thymocytes irradiated with 1 kR X rays in vitro were incubated at 37 degrees C with 10 mM glucose for 4 to 6 hr. During that time development of interphase death as judged by ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-07-01 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：:Cognitive impairments after brain irradiation seriously affect quality of life for patients, and there is currently no effective treatment. In this study using an irradiated rat model, the role of electroacupuncture was investigated for treatment of radiation-induced brain injury. Animals received 10 Gy exposure to th...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14561.1
更新日期：2017-06-01 00:00:00
abstract：:An analytical expression is developed for calculating the average energy deposited by an ion in a volume with dimensions less than the range of the secondary electrons produced. The expression is obtained by including two additional terms in an energy-restricted linear-energy-transfer equation. The usual energy-restri...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-12-01 00:00:00
abstract：:Evidence is presented for the formation of products in irradiated dinucleoside monophosphates in which both bases are damaged. The dinucleoside monophosphates d(GpT), d(GpC), d(TpG) and d(CpG) were X-irradiated in oxygenated aqueous solution. Product identification was by NMR spectroscopy. In products containing doubl...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
abstract：:We have previously proposed that survival curves for cells of murine NFSa fibrosarcomas after exposure to fast neutrons might demonstrate curvature when the neutron doses reach a level high enough to cure the fibrosarcomas. We report here that this is the case. Murine NFSa fibrosarcomas growing in the hind legs of syn...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-08-01 00:00:00
abstract：:Relatively few data are available on the prevalence of hyperthyroidism (TSH concentrations of <0.3 mIU/liter, with normal or elevated concentrations of free T4) in individuals exposed to radioiodines at low levels. The accident at the Chornobyl (Chernobyl) nuclear plant in Ukraine on April 26, 1986 exposed large numbe...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2003.1
更新日期：2010-12-01 00:00:00
abstract：:The effect of exposure of human epidermal keratinocytes to ionizing radiation, both in vivo and in vitro, on the expression of the epidermal growth factor receptor (EGF-R) was studied on the protein, mRNA, and functional levels. Quantitative fluorometry of short-term organ cultures incubated with a monoclonal antibody...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1993-10-01 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：:The LD50 of 46 salts of metals and rare earths (lanthanoids) was determined in mice. Half the LD50 of the compounds was then combined with lethal radiation (10.5 Gy) and the modification of survival time was scored. Only the metals beryllium and indium and the rare earths cerium, lanthanum and scandium displayed activ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-03-01 00:00:00
abstract：:The effects of X irradiation on oligodendrocyte-type-2-astrocyte (O-2A) progenitor cells derived from different regions of the perinatal central nervous system (CNS) of rats were investigated in vitro. The O-2A progenitor cells can differentiate into either oligodendrocytes or type-2 astrocytes. The depletion of these...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-10-01 00:00:00
abstract：:Clustered damage sites other than double-strand breaks (DSBs) have the potential to contribute to deleterious effects of ionizing radiation, such as cell killing and mutagenesis. In the companion article (Semenenko et al., Radiat. Res. 164, 180-193, 2005), a general Monte Carlo framework to simulate key steps in the b...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3414
更新日期：2005-08-01 00:00:00
abstract：:In previous studies, flavonoids, orientin and vicenin, that were isolated from the leaf extract of Ocimum sanctum, were found to protect mice against radiation injury. Several flavonoids are known to be good antioxidants. Therefore, the effect of orientin and vicenin on radiation-induced lipid peroxidation in vivo and...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)154[0455:rpbtof]2.0.co;2
更新日期：2000-10-01 00:00:00
abstract：:The linear no-threshold extrapolation from a dose-response relationship for ionizing radiation derived at higher doses to doses for which regulatory standards are proposed is being challenged by some scientists and defended by others. It appears that the risks associated with exposures to doses of interest are below t...
journal_title：Radiation research
pub_type：
doi：
更新日期：1998-12-01 00:00:00
abstract：:The immunocytochemical response to DNA damage induced by low-energy bismuth and carbon ions was investigated in normal human fibroblasts. Inside the nuclei, the traversing charged particles lead to the accumulation of proteins related to DNA lesions and repair along the ion trajectories. Irradiation under a standard g...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2003)159[0676:biohct]2.0.co;2
更新日期：2003-05-01 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：: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：: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：:It has been acknowledged for many years that radiation exposure induces delayed, non-targeted effects in the progeny of the irradiated cell. Evidence is beginning to demonstrate that among these delayed effects of radiation are epigenetic aberrations, including altered DNA methylation. To test the hypothesis that diff...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2390.1
更新日期：2011-05-01 00:00:00
abstract：:There has been ongoing debate and discussion concerning whether the funding source influenced the outcome of research on human health effects from exposure to radiofrequency fields (RF, electromagnetic waves that carry energy as they propagate in air and dense media). In a study of 225 publications, in which we sought...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15364.1
更新日期：2019-10-01 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：:The human breast is sensitive to radiation carcinogenesis, and genomic instability occurs early in breast cancer development. This study tests the hypothesis that ionizing radiation elicits genomic instability in finite life-span human mammary epithelial cells (HMEC) and asks whether densely ionizing radiation is a mo...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1317.1
更新日期：2008-07-01 00:00:00
abstract：:In boron neutron capture therapy, the absorbed dose from the (10)B(n,alpha)(7)Li reaction depends on the (10)B concentration and (10)B distribution in the irradiated volume. Thus compounds used in BNCT should have tumor-specific uptake and low accumulation in normal tissues. This study compares in a mouse model the (1...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1700.1
更新日期：2009-10-01 00:00:00
abstract：:It was reported by others that hands-free accessories increase the absorption of RF energy in a human head compared to a handset alone. The results of this study show that the opposite is observed when proper dosimetric methods are employed. It is pointed out that for correct estimation of the exposure level it is nec...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2003)159[0550:eotsit]2.0.co;2
更新日期：2003-04-01 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：: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：:Single crystals of guanine hydrobromide monohydrate, in which the guanine base is protonated at N7, were X-irradiated at 8 and 65 K. Using K-band ESR, ENDOR, and field-swept-ENDOR (FSE) techniques, the crystals were studied between 8 K and room temperature. There was evidence for five different radicals, RI-RV, immedi...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1991-02-01 00:00:00
abstract：:The microdosimetry of (10)B thermal neutron capture reactions should be considered as an essential step to be followed before studying the radiobiological aspects of boron neutron capture therapy. The boron dose itself is insufficient as the only quantity used to describe the biological effectiveness of the (10)B reac...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3257
更新日期：2004-12-01 00:00:00
abstract：:X rays have been shown to induce two forms of potentially lethal damage (PLD), "fast-repairing" PLD and "slowly repairing" PLD, whose repair is completed in 1 h and 4-6 h, respectively. In this study three modes of treatment with hypertonic solutions containing different NaCl concentrations for different durations (0....
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-01-01 00:00:00
