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) containing detergent, EDTA, and chloroform. It was found that DNA could be released from irradiated and inactivated cells simply by incubating them with the protease Pronase, and this DNA appeared to be in a form suitable for centrifugational analysis in neutral sucrose gradients. When cells were irradiated in the presence of oxygen, inactivation with ethanol gave a radiation-induced double-strand break (dsb) yield 1.8-fold higher than when inactivation was with CSE. Possible explanations of this are discussed. Using CSE inactivation, an oxygen enhancement ratio for dsb formation of 4.3 was observed and yields of dsb per Gray were in good agreement with results from other laboratories. At concentrations which enhanced cell killing 2.6-fold the "electron-affinic" type anoxic radiosensitizer misonidazole enhanced dsb formation 2.0-fold, whereas the nitroxyl free radical anoxic radiosensitizer norpseudopelletierine-N-oxyl had no significant effect on dsb yield although there was a possible slight enhancement at the higher doses used.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Tilby MJ,Loverock PSsubject
Has Abstractpub_date
1983-11-01 00:00:00pages
309-21issue
2eissn
0033-7587issn
1938-5404journal_volume
96pub_type
杂志文章abstract::A method was used to detect chromosome inversions as apparent or false sister chromatid exchanges (SCEs) in the first mitosis after gamma irradiation of human G0 cells. Dose-response relationships for small inversions have not been measured and reported previously, but it has been assumed that these are induced with a...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1995-08-01 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::A total of 155 primary bone sarcomas were found in 131 of the 246 beagles injected with 226Ra and 5 primary bone sarcomas were found in 4 of the 158 unexposed controls. Of these 155 bone sarcomas, 146 (94%) were osteosarcomas and 9 were non-osteosarcomas. An additional 31 primary bone sarcomas (28 osteosarcomas) devel...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1994-03-01 00:00:00
abstract::The effect of both hyperthermia and verapamil on cytotoxicity and transport of melphalan was studied in a pleiotropic drug-resistant Chinese hamster ovary cell line (CHRC5) and in the drug-sensitive parent line (AuxB1). The CHRC5 cell line was selected for resistance to colchicine but is also cross-resistant to other ...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1995-07-01 00:00:00
abstract::Little computational or experimental information is available on site-specific hydroxyl attack probabilities to DNA. In this study, an atomistic stochastic model of OH radical reactions with DNA was developed to compute relative OH attack probabilities at individual deoxyribose hydrogen atoms. A model of the self-comp...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2002)157[0038:ssoatt]2.0.co;2
更新日期:2002-01-01 00:00:00
abstract::The objective of this study was to determine whether a deficiency for either one of two repair processes influences the phenomenon of enhancement of radiation-induced cell killing by carboplatin which has been reported previously in one cell line (V79) and which is presumably a result of an interaction between these t...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1995-11-01 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::We previously described an enhanced sensitivity for cell killing and gamma-H2AX focus induction after both high-dose-rate and continuous low-dose-rate gamma irradiation in 14 primary fibroblast strains derived from hereditary-type retinoblastoma family members (both affected RB1(+/-) probands and unaffected RB1(+/+) p...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR1943.1
更新日期:2010-01-01 00:00:00
abstract::In this article, we describe recent methodological enhancements and findings from the dose reconstruction component of a study of health risks among U.S. radiologic technologists. An earlier version of the dosimetry published in 2006 used physical and statistical models, literature-reported exposure measurements for t...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR13542.1
更新日期:2014-11-01 00:00:00
abstract::To determine whether exposure to radiofrequency (RF) radiation can induce DNA damage or apoptosis, Molt-4 T lymphoblastoid cells were exposed with RF fields at frequencies and modulations of the type used by wireless communication devices. Four types of frequency/modulation forms were studied: 847.74 MHz code-division...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3127
更新日期:2004-02-01 00:00:00
abstract::Exposure to ionizing radiation alone or combined with traumatic tissue injury is a crucial life-threatening factor in nuclear and radiological incidents. Radiation injuries occur at the molecular, cellular, tissue and systemic levels; their mechanisms, however, remain largely unclear. Exposure to radiation combined wi...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR14647.1
更新日期:2017-11-01 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::Mortality data for B6CF1 mice exposed to 60Co gamma rays for the duration of life were used to make quantitative predictions of age-specific mortality observed in comparably exposed beagles. Simple Kaplan-Meier survival curves for the beagles and their 95% confidence intervals were computed for each dose-rate group ob...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1998-05-01 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::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::While lifespan studies provide basic information for estimating the risk of ionizing radiation, findings on the effect of low-dose/low-dose-rate irradiation on the lifespan of mammals are controversial. Here we evaluate the effect of continuous exposure to low-dose-rate γ radiation on the lifespan of mice with acceler...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR2977.1
更新日期:2013-06-01 00:00:00
abstract::Wistar rats (36) were exposed daily throughout pregnancy to a power density level of 35 mW/cm2 of 6000-MHz microwave radiation (11), sham irradiated (10), or used as control animals (15). Litters were culled to a maximum of eight F1a offspring/litter (total = 124) on Postnatal Day 1 and subjected to a series of reflex...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1984-02-01 00:00:00
abstract::Radiation sensitivity was measured by the micronucleus assay in T lymphocytes of the spleen and in fibroblasts derived from three inbred strains of mice, BALB/c, A/J and C3H/He. A linear correlation between the surviving fraction and the micronucleus frequency was obtained. There were clear differences in the radiosen...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1997-10-01 00:00:00
abstract::The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) is the key functional element in the DNA-PK complex that drives nonhomologous end joining (NHEJ), the predominant DNA double-strand break (DSB) repair mechanism operating to rejoin such breaks in mammalian cells after exposure to ionizing radiation. It h...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR2092.1
更新日期:2011-01-01 00:00:00
abstract::We studied the spatial and temporal distributions of foci of the phosphorylated form of the histone protein H2AX (gamma-H2AX), which is known to be activated by double-strand breaks after irradiation of human fibroblast cells with high-energy silicon (54 keV/microm) and iron (176 keV/microm) ions. Here we present data...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3431.1
更新日期:2005-10-01 00:00:00
abstract::Deep-space travel presents risks of exposure to ionizing radiation composed of a spectrum of low-fluence protons (1H) and high-charge and energy (HZE) iron nuclei (e.g., 56Fe). When exposed to galactic cosmic rays, each cell in the body may be traversed by 1H every 3-4 days and HZE nuclei every 3-4 months. The effects...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR14667.1
更新日期:2017-08-01 00:00:00
abstract::Human blood cultures were exposed to a 1.9 GHz continuous-wave (CW) radiofrequency (RF) field for 2 h using a series of six circularly polarized, cylindrical waveguides. Mean specific absorption rates (SARs) of 0.0, 0.1, 0.26, 0.92, 2.4 and 10 W/kg were achieved, and the temperature within the cultures during a 2-h ex...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2002)158[0523:ddamii]2.0.co;2
更新日期:2002-10-01 00:00:00
abstract::The potential for radiogenic neoplasia from charged-particle irradiation has been estimated using the Harderian gland of the mouse as a test system. Particles ranging in Z from Z = 1 (proton) to Z = 41 (niobium), in energy from 228 to 670A MeV, and in LET from 0.4 to 464 keV/microns were produced at the Lawrence Berke...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1993-12-01 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::Phosphorylated ATM immunofluorescence staining was used to investigate the dose-response relationship for the number of DNA double-strand breaks (DSBs) induced in primary normal human fibroblasts irradiated with doses from 1.2 to 200 mGy. The induction of DSBs showed a supralinear dose-response relationship. Radiation...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR1255.1
更新日期:2008-09-01 00:00:00
abstract::The photodynamic properties of a second-generation photodynamic sensitizer, meta-tetra(hydroxyphenyl)chlorin (mTHPC) were studied by dye-sensitized photoinactivation (650 nm) of HT29 human adenocarcinoma cells in culture. The photocytotoxicity of mTHPC in vitro depended on the presence of molecular oxygen. A strong in...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1999-10-01 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::Vascular injury after radiation exposure contributes to multiple types of tissue injury through a cascade of events. Some of the earliest consequences of radiation damage include increased vascular permeability and promotion of inflammation, which is partially manifested by increased leukocyte-endothelial (L/E) intera...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR14896.1
更新日期:2018-07-01 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::We have previously used NotI as the marker enzyme (recognizing GCGGCCGC) in a genome scanning approach for detection of mutations induced in mouse spermatogonia and estimated the mutation induction rate as about 0.7 x 10(-5) per locus per Gy. To see whether different parts of the genome have different sensitivities fo...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR0926.1
更新日期:2007-08-01 00:00:00