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 inhibition of the photocytotoxicity of mTHPC was observed upon addition of sodium azide, a known singlet oxygen quencher. Photocytotoxicity was not inhibited by scavengers of superoxide anion radical, hydrogen peroxide and hydroxyl radicals. We suggest that mTHPC photosensitizes cell killing predominantly by type II, singlet oxygen-mediated photodynamic reactions. Illumination of cells preloaded with mTHPC induced peroxidation of membrane lipids. Inhibition of photoperoxidation by alpha-tocopherol (0.1 mM) present during illumination did not result in any decrease in toxicity, suggesting that reactions of lipid peroxidation play only a minor role in the overall photocytotoxic effect of mTHPC.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Melnikova VO,Bezdetnaya LN,Potapenko AY,Guillemin Fsubject
Has Abstractpub_date
1999-10-01 00:00:00pages
428-35issue
4eissn
0033-7587issn
1938-5404journal_volume
152pub_type
杂志文章abstract：:The detection of (41)Ca atoms in tooth enamel using accelerator mass spectrometry is suggested as a method capable of reconstructing thermal neutron exposures from atomic bomb survivors in Hiroshima and Nagasaki. In general, (41)Ca atoms are produced via thermal neutron capture by stable (40)Ca. Thus any (41)Ca atoms ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2043.1
更新日期：2010-08-01 00:00:00
abstract：:The increasingly wider use of microdosimetry in fields other than pure radiobiological research, especially in "practical" domains such as radiation protection and medical physics, has created a number of new practitioners who are not fully acquainted with many of the experimental pitfalls which beset the aspiring mic...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-10-01 00:00:00
abstract：:As part of a long-term study of the effects of irradiation during development, prenatal and early neonatal mortality were evaluated for beagles exposed in utero at 8 days postcoitus (dpc), 28 dpc, 55 dpc, or 2 days postpartum. Mean doses used were 0,0.16, or 0.83 Gy. A decrease in whelping rates was observed for femal...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-07-01 00:00:00
abstract：:A recent publication by Leith et al. (Cancer Res. 51, 4111-4113, 1991) showed that administration of epidermal growth factor (EGF) (0.25 mg/kg; q.i.d. x 7) to mice bearing xenografted A431 human epidermoid cancers produced increased tumor growth and a reduction of the percentage of hypoxic cells within neoplasms. In c...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：:1. A survival curve for the colony-forming ability of mouse bone marrow cells irradiated in vivo with Co60 gamma-rays has been obtained. The curve may be characterized by D0 of 95 rads and an extrapolation number of 1.5. 2. Comparison with the survival curve obtained for irradiated in vitro indicated a statistically s...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1962-06-01 00:00:00
abstract：:It is well established that high-LET radiations efficiently induce chromosome aberrations. However, data on the effect of protons on telomere maintenance, as involved in genomic stability, are scarce and contradictory. Here we demonstrate that high-LET protons induce telomere lengthening in human primary fibroblasts a...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2127.1
更新日期：2010-11-01 00:00:00
abstract：:Three somatic mutation assays were evaluated in men exposed to low-dose, whole-body, ionizing radiation. Blood samples were obtained between 1992 and 1999 from 625 Russian Chernobyl cleanup workers and 182 Russian controls. The assays were chromosome translocations in lymphocytes detected by FISH, hypoxanthine phospho...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2002)158[0424:tsgbac]2.0.co;2
更新日期：2002-10-01 00:00:00
abstract：:The anoxic sensitization of bacterial spores by added H2O2 has been studied. Two mechanistic pathways for damage from H2O2 were found; one of these requires the presence of OH radicals. For this kind of damage, the relationship between H2O2 and OH appears to be that they are reactants. O-2 (and/or HO2), the product of...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-04-01 00:00:00
abstract：:Clustered DNA damage is considered an important factor in determining the biological consequences of ionizing radiation. In this study, we successfully estimated the localization of abasic sites (APs) in DNA exposed to ionizing radiation using fluorescence resonance energy transfer (FRET) without any involvement of re...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR13780.1
更新日期：2015-01-01 00:00:00
abstract：:Exposure of cells to heat induces thermotolerance, a transient resistance to subsequent heat challenges. It has been shown that thermotolerance is correlated in time with the enhanced synthesis of heat shock proteins. In this study, the association of induced heat shock proteins with various cellular fractions was inv...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-03-01 00:00:00
abstract：:Molecular imaging is an evolving science that is concerned with the development of novel imaging probes and biomarkers that can be used to non-invasively image molecular and cellular processes. This special issue approaches molecular imaging in the context of radiation research, focusing on biomarkers and imaging meth...
journal_title：Radiation research
pub_type：
doi：10.1667/rr2959.1
更新日期：2012-04-01 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：:Thymic explant cultures were used to study the radiosensitivity of nonlymphoid thymic components in dogs. Thymic fragments from fetal (50 days gestation), newborn, and juvenile (70 days old) dogs were irradiated in vitro at 0, 0.5, 1, 2, or 4 Gy prior to culture. Colonies were classified as epithelial, spindle, or mix...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-07-01 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：: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：:The threat of exposure to ionizing radiation from a nuclear reactor accident or deliberate terrorist actions is a significant public health concern. The lung is particularly susceptible to radiation-induced injury from external sources or inhalation of radioactive particles from radioactive fallout. Radiation-induced ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14686.1
更新日期：2017-11-01 00:00:00
abstract：:Although skin is usually exposed during human exposures to ionizing radiation, there have been no thorough examinations of the transcriptional response of skin fibroblasts and keratinocytes to radiation. The transcriptional response of quiescent primary fibroblasts and keratinocytes exposed to from 10 cGy to 5 Gy and ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR1677.1
更新日期：2009-07-01 00:00:00
abstract：:Tissue ablation by ultraviolet excimer lasers results in exposure of viable cells to subablative doses of radiation. To understand the potential biological consequences better, we have studied changes in gene expression in cultured human skin fibroblasts exposed to either 193- or 248-nm laser light. Northern blot anal...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-09-01 00:00:00
abstract：:Currently, there is a serious absence of pharmaceutically attractive small molecules that mitigate the lethal effects of an accidental or intentional public exposure to toxic doses of ionizing radiation. Moreover, cellular systems that emulate the radiobiologically relevant cell populations and that are suitable for h...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2810.1
更新日期：2012-09-01 00:00:00
abstract：:Telomeres cap the ends of chromosomes, preventing end-to-end fusions and subsequent chromosome instability. Here we used a telomerase knockout model to investigate whether telomerase participates in the processes of DNA break repair by de novo synthesis of telomere repeats at broken chromosome ends (chromosome healing...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3203
更新日期：2004-08-01 00:00:00
abstract：:The intrinsic radiosensitivity of tumor cells is most frequently reported for asynchronous populations, although cell cycle variation in radiosensitivity is known to be significant. Linear-quadratic analyses of survival data for asynchronous human tumor cells show wide variations in the alpha coefficient with smaller ...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1997-04-01 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：:The effect of acute exposure to ultrawideband (UWB) electromagnetic radiation on the Primate Equilibrium Platform (PEP) task, where the monkey's task is to manipulate a joystick control to compensate for the random perturbations in the pitch plane that are generated by a computer at unpredictable intervals, was examin...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1995-07-01 00:00:00
abstract：:In light-ion radiation therapy, both the dose and the local energy spectrum, which is often characterized with the linear energy transfer (LET), must be considered. In treatment optimization, it is advantageous to use a radiobiological model that analytically accounts for both dose and LET for the ion type of interest...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR2045.1
更新日期：2010-10-01 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：:Hyperthermic sensitivities of Escherichia coli B/r and Bs-1 were determined for lag-, midlog-, and stationary-phase cells at 47, 48, and 49 degrees C. In both strains midlog-phase cells were strikingly more heat sensitive (100-fold greater killing after 4 h at 48 degrees C) than stationary-phase cells, with intermedia...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1986-04-01 00:00:00
abstract：:New data are given on the use of oxalic acid, in light and heavy water solutions, for in-pile chemical dosimetry. The method of calculating the absorbed doses in low-Z materials is described. Results of chemical measurements in the core of the heavy-water-moderated reactor at Vinca (Yugoslavia) are compared with the r...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1968-12-01 00:00:00
abstract：:To study the dynamics of protein recruitment to DNA lesions, ion beams can be used to generate extremely localized DNA damage within restricted regions of the nuclei. This inhomogeneous spatial distribution of lesions can be visualized indirectly and rapidly in the form of radiation-induced foci using immunocytochemic...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr3374
更新日期：2005-06-01 00:00:00
abstract：:In recent years, there has been increasing concern over the possibility of a radiological or nuclear incident occurring somewhere in the world. Intelligence agencies frequently report that terrorist groups and rogue nations are seeking to obtain radiological or nuclear weapons of mass destruction. In addition, there e...
journal_title：Radiation research
pub_type：
doi：10.1667/RR14810.1
更新日期：2017-08-01 00:00:00
abstract：:We recently reported that daily dietary supplementation with 100 µg selenium (a dose exceeding a rat's nutritional requirement by about 33-fold) initiated immediately after total-body irradiation (TBI) and maintained for 21 weeks mitigates radiation nephropathy in a rat model as indicated by blood urea nitrogen (BUN) ...
journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/rr2456.1
更新日期：2011-09-01 00:00:00
