Abstract:
:The presence of oxygen-deficient tumor cells is a critical issue in cancer therapy. To identify tumor hypoxia, tissue partial oxygen pressure (pO2) can be measured directly. The OxyLite system allows determination of pO2 in tumors and permits continuous measurements of pO2 at a fixed point. In this study, this system was used to continuously measure pO2 in R3327-AT tumors in animals anesthetized with isoflurane. In addition, continuous pO2 measurement was performed in the muscle in non-tumor-bearing animals. In animals breathing isoflurane balanced by air, tumor pO2 at fixed positions decreased rapidly within 1-2 min of probe positioning but remained stable thereafter. In animals breathing isoflurane balanced by pure oxygen, tumor pO2 was higher and remained high. We also measured pO2 values at multiple positions in R3327-AT tumors of various sizes, with anesthetized animals breathing either air or pure oxygen. Our data showed that the frequency of pO2 measurements below 2.5 or 5.0 mmHg was significantly higher in animals breathing air than in animals breathing pure oxygen. Measurements in different-sized tumors showed that the mean pO2 value decreased as tumor volume increased, with the largest change occurring between tumor volumes of 100 and 200 mm3. Our data demonstrate that the OxyLite system, when used with isoflurane anesthesia, is a valuable tool in the study of tumor hypoxia.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Wen B,Urano M,O'Donoghue JA,Ling CCdoi
10.1667/RR3602.1subject
Has Abstractpub_date
2006-09-01 00:00:00pages
512-8issue
3eissn
0033-7587issn
1938-5404pii
RR3602journal_volume
166pub_type
杂志文章abstract::Caffeine was found to potentiate X-ray-induced killing of human diploid fibroblasts from a normal subject and an ataxia-telangiectasia (AT) patient when it was present at 2 mM concentration for 30 to 66 hr postirradiation. The dose-modifying factor for caffeine-treated normal cells had an average value of 1.26 +/- 0.1...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1983-07-01 00:00:00
abstract::Studies have causally linked external thyroid radiation exposure in childhood with thyroid cancer. In 1995, investigators conducted relative risk analyses of pooled data from seven epidemiologic studies. Doses were mostly <10 Gy, although childhood cancer therapies can result in thyroid doses >50 Gy. We pooled data fr...
journal_title:Radiation research
pub_type: 杂志文章,meta分析
doi:10.1667/RR14213.1
更新日期:2016-05-01 00:00:00
abstract::Alteration of the radiation-induced changes in wound contraction, collagen synthesis and wound histology by ascorbic acid was studied in mice exposed to 10, 16 and 20 Gy of fractionated (2 Gy/fraction) gamma radiation. The animals were given double-distilled water or ascorbic acid daily before exposure to 2 Gy/day of ...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2003)159[0371:eoteoa]2.0.co;2
更新日期:2003-03-01 00:00:00
abstract::We studied the effects of extremely low-frequency (50 Hz) electromagnetic fields (EMFs) on peripheral human blood lymphocytes and DBY747 Saccharomyces cerevisiae. Graded exposure to 50 Hz magnetic flux density was obtained with a Helmholtz coil system set at 1, 10 or 100 microT for 18 h. The effects of EMFs on DNA dam...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3426.1
更新日期:2005-09-01 00:00:00
abstract::The lactose operon functions under the control of the repressor-operator system. Binding of the repressor to the operator prevents the expression of the structural genes. This interaction can be destroyed by the binding of an inducer to the repressor. If ionizing radiations damage the partners, a dramatic dysfunction ...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3336
更新日期:2005-04-01 00:00:00
abstract::The toxicity of 137Cs in the beagle dog was investigated at the Inhalation Toxicology Research Institute (ITRI) and Argonne National Laboratory (ANL) as part of programs to evaluate the biological effects of both radionuclides in atomic bomb fallout and internally deposited fission-product radionuclides. In the ITRI s...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1996-11-01 00:00:00
abstract::Chinese hamster ovary cells in suspension cultures were heated for various times at 41.5, 43.5, and 45.5 degrees C, and quantitative determinations of microblebbing and macroblebbing of the cell membrane were performed for cells maintained at 4, 25, and 37 degrees C after hyperthermia. The percentage of cells with ble...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1986-03-01 00:00:00
abstract::To compare the effects of exposure to a near-resonant frequency of microwaves at two orientations with a higher frequency exposure, five rhesus monkeys were exposed for 4 hr to 225 MHz, electric field oriented parallel to the long axis of the body (225 MHz-E), and to 225 MHz, magnetic field orientation (225 MHz-H), or...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1985-04-01 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::We describe a rapid assay to predict intrinsic radiosensitivity of normal tissues based on the radiation-induced cytotoxic response of a number of types of white blood cells. Twenty-four hours after irradiation, leukocytes were prepared for analysis by flow cytometry. Radiation-induced cytotoxicity was characterized b...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1997-01-01 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::If the limited life span of hematopoietic tissues in vitro is due to a finite proliferative capacity of individual stem cells, one might expect tissues of young donors to possess a greater proliferative capacity and to contain a larger population of primitive stem cells than those of older donors. To test this hypothe...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1987-10-01 00:00:00
abstract::Nonhuman organisms are being exposed to ionizing radiations at radionuclide-contaminated sites around the world. Direct methods are seldom available for measuring biologically relevant doses received by these organisms. Here we extend biological dosimetry techniques, which are much better developed for humans and a fe...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/0033-7587(2000)153[0752:ctitab]2.0.co;2
更新日期:2000-06-01 00:00:00
abstract::The immune response of guinea pigs to Q fever vaccine following 75 to 250 R (60 to 180 rads) of acute whole-body irradiations was investigated. Complement-fixing (CF) antibody titers and protection against febrile response to challenge with virulent Coxiella burnetii were studied. Exposures ranging from 75 to 250 R, 2...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1968-10-01 00:00:00
abstract::To estimate the effect of 50 Hz magnetic-field exposure on genome-wide gene expression, the yeast Saccharomyces cerevisiae was used as a model for eukaryotes. 2D PAGE (about 1,000 spots) for protein and cDNA microarray (about 5,900 genes) analysis for mRNA were performed. The cells were exposed to 50 Hz vertical magne...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3006
更新日期:2003-07-01 00:00:00
abstract::Here we report that suramin sensitizes LM217, MDA-MB-468, T98G and A431 cells to ionizing radiation. Suramin sensitized cells to X radiation in a dose-dependent fashion, and longer exposure to suramin before X irradiation resulted in more efficient sensitization. The dose-modifying factors calculated from the survival...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3217
更新日期:2004-09-01 00:00:00
abstract::Deep underground laboratories (DULs) were originally created to host particle, astroparticle or nuclear physics experiments requiring a low-background environment with vastly reduced levels of cosmic-ray particle interference. More recently, the range of science projects requiring an underground experiment site has gr...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR15083.1
更新日期:2018-09-01 00:00:00
abstract::Whether inner-shell ionizations of DNA atoms, called core ionizations, are critical events for cell inactivation by ionizing radiations such as 100 keV electrons and gamma rays has been investigated. The number of core ionizations in DNA atoms per gray of the two types of radiations is calculated from various Monte Ca...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR0451.1
更新日期:2007-04-01 00:00:00
abstract::While the link between risk of leukemia and acute radiation exposure is well established for large doses received acutely, uncertainty remains around the translation of these risk estimates to occupational exposure scenarios where the doses are low and accumulated over time, possibly over many years. We present leukem...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR15358.1
更新日期:2019-11-01 00:00:00
abstract::Previous work from our laboratory suggested that neuronal chromatin structure may be altered immediately after exposure to ionizing radiation. In the present study, whole brains of 4-month-old male Fisher 344 rats were irradiated with a dose of 25 Gy. The kinetics of restoring the chromatin structure to its unirradiat...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1988-04-01 00:00:00
abstract::The retention of 241Am in mice 48 h after administration by gavage is reported here. The 241Am was given to mice in the form of either 241Am nitrate or 241Am citrate. The 241Am was also injected into rats in the same form. The homogenized livers of those rats were subsequently administered by gavage to another group o...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1987-08-01 00:00:00
abstract::Radiation-induced cell death is thought to be caused by nuclear DNA damage that cannot be repaired. However, in this study we found that a delayed increase of mitochondrial reactive oxygen species (ROS) is responsible for some of the radiation-induced cell death in normal human fibroblast cells. We have previously rep...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR13772.1
更新日期:2015-04-01 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::Information on early internal radiation doses in Fukushima after the nuclear power plant accident on March 11, 2011, is quite limited due to initial organizational difficulties, high background radiation and contamination of radiation measuring devices. In Nagasaki, approximately 1,200 km away from Fukushima, the inte...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR3232.1
更新日期:2013-06-01 00:00:00
abstract::Metallothionein (MT), the synthesis of which can be induced by metalloelement administration, is a known radical scavenger. This study investigated the possible protective effect of MT against acute radiation injury. Manganese chloride (10 mg of manganese/kg) was administered intraperitoneally to male C3H/He mice 24 h...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::An analysis was conducted of 27,982 deaths among 106,020 persons employed at four Federal nuclear plants in Oak Ridge, Tennessee, between 1943 and 1985. The main objectives were to extend the evaluation of the health effects of employment in the nuclear industry in Oak Ridge to include most workers who were omitted fr...
journal_title:Radiation research
pub_type: 杂志文章
doi:
更新日期:1997-07-01 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::To examine more fully the nature of chromosomal radiosensitivity in ataxia telangiectasia (AT) cells, we employed 24-color combinatorial painting to visualize 137Cs gamma-ray-induced chromosome-type aberrations in cells of two AT and one normal primary human fibroblast strains irradiated in log-phase growth. As a meas...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr3255
更新日期:2004-11-01 00:00:00
abstract::In previous studies we determined a gene expression signature in baboons for predicting the severity of hematological acute radiation syndrome. We subsequently validated a set of eight of these genes in leukemia patients undergoing total-body irradiation. In the current study, we addressed the effect of intra-individu...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/RR15013.1
更新日期:2018-09-01 00:00:00
abstract::To date, there are no safe and effective drugs available for protection against ionizing radiation damage. Therefore, a great need exists to identify and develop non-toxic agents that will be useful as radioprotectors or postirradiation therapies under a variety of operational scenarios. We have developed a new pharma...
journal_title:Radiation research
pub_type: 杂志文章
doi:10.1667/rr2657.1
更新日期:2012-05-01 00:00:00