Abstract：
:Evaluation of the probability of biological phenomena per cell by colony formation, requires knowledge not only of the number of cells at risk but also of their microdistribution. In the present study, the influence of cellular multiplicity (number of cells per potential colony-forming unit) on the determination of radiation sensitivity is evaluated for a range of multiplicity distributions. Cell surviving fraction was calculated using no multiplicity correction, an average multiplicity correction or the fractional distribution of multiplicities of the control and irradiated population. The results obtained show that: (a) multiplicity corrections are required when the number of cells per potential colony-forming unit is greater than 1.00 either immediately after plating or at the time of irradiation; (b) both the control and irradiated populations must be corrected for multiplicity; (c) multiplicity errors are most pronounced in the low-dose range, e.g. in the survival range with 2 Gy; and (d) the error introduced by using an average vs fractional distribution of multiplicities increases with the multiplicity dispersion. Seemingly small errors due to uncorrected multiplicity effects lead to markedly different predicted isoeffect doses when amplified through multiple (e.g. 30) fractions.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Gerweck LE,Dullea R,Zaidi ST,Budach W,Hartford Asubject
Has Abstractpub_date
1994-06-01 00:00:00pages
361-6issue
3eissn
0033-7587issn
1938-5404journal_volume
138pub_type
杂志文章abstract：:Radiation-induced heart disease (RIHD) is a serious side effect of radiotherapy for intrathoracic and chest wall tumors. The threshold dose for development of clinically significant RIHD is believed to be lower than previously assumed. Therefore, research into mechanisms of RIHD has gained substantial momentum. RIHD b...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/rr2933.1
更新日期：2012-07-01 00:00:00
abstract：:The German Thorotrast study comprises 2,326 patients and 1,890 controls. Forty-eight Thorotrast patients and 239 controls are still alive and are invited for a follow-up examination every 2 years. In the deceased patients, the following neoplastic diseases with excess rates were registered (Thorotrast/controls): liver...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1999-12-01 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：:Radiation exposure from a number of terrestrial sources is associated with an increased risk for atherosclerosis. Recently, concern over whether exposure to cosmic radiation might pose a similar risk for astronauts has increased. To address this question, we examined the effect of 2 to 5 Gy iron ions ((56)Fe), a parti...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2482.1
更新日期：2011-06-01 00:00:00
abstract：:Bcl-X(S) is a pro-apoptosis member of the Bcl2 family that has been shown to induce cell death and enhance chemosensitivity. We have investigated the effect of Bcl-X(S) overexpression on radiation sensitivity. Using a tetracycline-repressible system, we found that removal of tetracycline for 16 h induced Bcl-X(S) and ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3169
更新日期：2004-05-01 00:00:00
abstract：:Using atomic force microscopy (AFM), we have investigated neutron-induced DNA double-strand breaks in plasmids in aqueous solution. AFM permits direct measurement of individual DNA molecules with an accuracy of a few nanometers. Furthermore, the analysis of the DNA fragment size distribution is non-parametric, whereas...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1998-12-01 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
abstract：:This commentary considers modulation as a factor of potential biological importance in assessment of risk of radiofrequency (RF) energy emitted by communications systems and other technologies. Modulation introduces a spread of frequencies into a carrier waveform, but in nearly all cases this spread is small compared ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3191
更新日期：2004-08-01 00:00:00
abstract：:Groups of rats were administered different doses of X rays (7.5 and 15 Gy), and the effect on the permeability of their lungs was evaluated during a time frame within which radiation pneumonitis develops. Sham-exposed animals served as controls. End points surveyed included lung weight and increases in the total prote...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1993-05-01 00:00:00
abstract：:Experimental work indicates that one of the mechanisms of tumor control by hyperthermia may be damage to blood vessels, resulting in decreased blood flow to the neoplasms. Among the various elements of the microvasculature, endothelial cells are the most important possible targets of thermal injury. Furthermore, neopl...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-08-01 00:00:00
abstract：:Mice were irradiated with 1 Gy of fission neutrons. At intervals up to 15 days after irradiation undifferentiated spermatogonia were counted in whole mounts of seminiferous tubules in up to eight stages of the epithelial cycle. From Day 6 onward lower numbers of spermatogonia were found in the areas which were in stag...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-03-01 00:00:00
abstract：:The capacity of plateau-phase Chinese hamster V79 and normal and transformed C3H-10T1/2 cells for repair of potentially lethal radiation damage (PLD) was evaluated for cells irradiated alone or given combined treatments of heat and radiation. The data show that all cell lines tested could repair PLD and that transform...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
abstract：:To evaluate whether DNA alterations in mature spermatozoa could stem from DNA damage induced in immature germ cells, testis cells and spermatozoa were analyzed by the comet assay and by the sperm chromatin structure assay 14, 45 and 100 days after in vivo X irradiation of the testes. These times were selected, accordi...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3053
更新日期：2003-10-01 00:00:00
abstract：:CD34 antigen is a novel marker for human hematopoietic stem/progenitor cells. In the present study, two cell fractions, CD34low and CD34high, were prepared from steady-state human peripheral blood on the basis of CD34 antigen expression. The colony-forming unit megakaryocytes (CFU-Meg) contained in each cell fraction ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3396
更新日期：2005-07-01 00:00:00
abstract：:Current lung cancer risk estimates after exposure to low-linear energy transfer radiation such as X rays are based on studies of people exposed to such radiation at high dose rates, for example the atomic bomb survivors. Radiobiology and animal experiments suggest that risks from exposure at low to moderate dose rates...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-06-01 00:00:00
abstract：:Experimental data from laboratory animals indicate that the same extent of DNA damage or the same mutations in oncogenes and tumor suppressor genes in different hosts result in widely differing cancer development because of numerous polymorphic tumor susceptibility genes. Similarly, recent epidemiological data indicat...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/rr3333.1
更新日期：2005-10-01 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：:This study was undertaken to determine if structural alterations of the bulk chromatin and the amount of protein associated with the nuclear matrix in cerebellar neurons depend on radiation dose and a cell's state of oxygenation. After irradiation with 2.5 to 25.0 Gy under both aerobic and anoxic conditions, the sensi...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-07-01 00:00:00
abstract：:The hyperthermic inhibition of cellular DNA synthesis, i.e., reduction in replicon initiation and delay in DNA chain elongation, was previously postulated to be involved in the induction of chromosomal aberrations believed to be largely responsible for killing S-phase cells. Utilizing asynchronous Chinese hamster ovar...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-04-01 00:00:00
abstract：:The (11)B(p,alpha)(8)Be* nuclear reaction was assessed for its ability to quantitatively map the in vivo subcellular distribution of boron within gliosarcomas treated with a boronated neutron capture therapy agent. Intracranial 9L gliosarcomas were produced in Fischer 344 rats. Fourteen days later, the majority of the...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3085
更新日期：2003-12-01 00:00:00
abstract：:Triple negative breast cancer (TNBC) is an aggressive disease with a high risk of recurrence and death. Here, we present a novel strategy to enhance the radiotherapy of TNBC by combining gold nanoparticles (AuNPs) with pentamidine, a clinically approved anti-parasitic agent with anti-cancer properties. The radiosensit...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14315.1
更新日期：2016-05-01 00:00:00
abstract：:Radiation is an independent risk factor for cardiovascular and cerebrovascular disease in cancer patients. Modern radiotherapy techniques reduce the volume of the heart and major coronary vessels exposed to high doses, but some exposure is often unavoidable. Radiation damage to the myocardium is caused primarily by in...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR1862.1
更新日期：2010-12-01 00:00:00
abstract：:During the pulsed-electron beam direct grafting of neat styrene onto poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) substrate, the radiolytically-produced styryl and carbon-centered FEP radicals undergo various desired and undesired competing reactions. In this study, a high-dose rate is used to impede the und...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15006.1
更新日期：2018-09-01 00:00:00
abstract：:To compare the genotoxic effects of high-LET ionizing radiation to those of low-LET radiation, we investigated the responses of human lymphoblastoid cells to DNA damage TK6 after treatment with either low-LET X rays or high-LET iron ions (1000 keV/microm). A highly localized distribution of gammaH2AX/RAD51 foci was ob...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2002)158[0678:dccpih]2.0.co;2
更新日期：2002-12-01 00:00:00
abstract：:A formalism developed in the first paper in this series, based on the generalized Theory of Dual Radiation Action, is applied to survival data for cells exposed to soft X rays. It is shown that, in contrast to previous published analyses, this formalism--modified to account for the attenuation of dose across the sensi...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1984-09-01 00:00:00
abstract：:In the decade after the bombings of Hiroshima and Nagasaki, several large cohorts of survivors were organized for studies of radiation health effects. The U.S. Atomic Bomb Casualty Commission (ABCC) and its U.S./Japan successor, the Radiation Effects Research Foundation (RERF), have performed continuous studies since ...
journal_title：Radiation research
pub_type： 杂志文章,评审
doi：10.1667/RR3546.1
更新日期：2006-07-01 00:00:00
abstract：:Transforming growth factor-β-activated kinase 1 (TAK1) appears to play a role in inhibiting apoptotic death in response to multiple stresses. To assess the role of TAK1 in X-ray induced apoptosis and cell death, we irradiated parental and siRNA-TAK1-knockdown HeLa cells. Changes in gene expression levels with and with...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2792.1
更新日期：2012-06-01 00:00:00
abstract：:In this study, we sought to determine how diffusion-weighted imaging (DWI) and proton magnetic resonance spectroscopy (1H-MRS) features are associated with histopathological results, and explored the cellular mechanisms of DWI and 1H-MRS in early radiosensitivity of transplanted liver tumors. VX2 tumors were implanted...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR15140.1
更新日期：2019-01-01 00:00:00
abstract：:The monohydroxylated fatty acid content of peripheral blood mononuclear cells from 23 cleanup workers and 16 unexposed individuals was studied in relation to their immune status after the Chernobyl accident. Men with absorbed doses below 0.32 Gy showed higher levels of free and esterified 12-hydroxyeicosatetraenoic ac...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2001)156[0476:mfacip]2.0.co;2
更新日期：2001-11-01 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
