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Results 251 - 300 of 1795
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Kuwahara Yoshikazu - - 2009
Radiotherapy is one of the major therapeutic modalities for eradicating malignant tumors. However, the existence of radioresistant cells remains one of the most critical obstacles in radiotherapy and radiochemotherapy. Standard radiotherapy for tumor treatment consists of approximately 2 Gy once a day, 5 days a week, over a period of ...
Wu F - - 2009
TRAIL induces apoptosis in a variety of tumorigenic and transformed cell lines, but not in many normal cells. Recent studies have demonstrated that death receptor 5 (DR5), one of the two death receptors bound by TRAIL, showed expression in most malignantly transformed cells. This study evaluated effects of a monoclonal ...
Gámez M - - 2009
The effect of radiation on a cell population is described by a two-dimensional nonlinear system of differential equations. If the radiation rate is not too high, the system is known to have an asymptotically stable equilibrium. First, for the monitoring of this effect, the concept of observability is applied. For ...
Youn Hyun-Yi - - 2009
The present study demonstrates narrowband short-wavelengths radiation- (400, 420, and 435.8 nm) induced cellular damage of cultured human retinal pigment epithelial cells using in vitro biological assays to determine wavelengths that are responsible for photochemical lesions of the retina. This work involved the exposure of retinal pigment epithelial (RPE) cells ...
Kohli D
The use of cell phones is increasing worldwide at a phenomenal pace. While cellular communication has dramatically influenced our lifestyle, its impact on human health has not been completely assessed. Widespread concern continues in the community about the deleterious effects of radiofrequency radiations (with which cell phones operate) on human ...
Wendisch M - - 2009
Aim: The cellular damage of ionising radiation depends on dose, physical radiation quality (e. g. LET) and intracellular radionuclide uptake. The influence of two beta emitters (188Re and 131I) on the thyroid cell line PCCl3 was studied. Furthermore, we analysed the effect of intracellular accumulation. Methods: The thyroid cell line ...
Beneduci Amerigo - - 2009
The potential antiproliferative effects of low power millimeter waves (MMWs) at 42.20 and 53.57 GHz on RPMI 7932 human skin melanoma cells were evaluated in vitro in order to ascertain if these two frequencies, comprised in the range of frequency used in millimeter wave therapy, would have a similar effect ...
Ryan Lorna A - - 2009
PURPOSE: A previous study comparing the bystander effect and low-dose hypersensitivity found that they were inversely correlated. In the current study seven cell lines with established bystander effect and hyper-radiosensitivity/increased radioresistance (HRS/IRR) were further screened for the presence of an adaptive response. MATERIALS AND METHODS: Cell survival after exposure to ...
Chen Liang - - 2009
The cell killing abilities of soft X-rays on and off the oxygen K-shell edges on yeast cells have been investigated using a micrometer soft X-ray microprobe from synchrotron radiation. The dose depositions at different X-ray energies in the cell were discussed. At the same time, the cells were irradiated by ...
Edin Nina Jeppesen - - 2009
Irradiation of T-47D cells with 0.3 Gy delivered by a (60)Co source at a low dose rate of 0.3 Gy/h abolished low-dose hyper-radiosensitivity (HRS) for at least 14 months (with continuous cell culturing), while the same dose administered acutely (40 Gy/h) eliminated HRS for less than 24 h. Medium transferred ...
Eke Iris - - 2009
BACKGROUND: The constant increase of cancer cell resistance to radio- and chemotherapy hampers improvement of patient survival and requires novel targeting approaches. Integrin-Linked Kinase (ILK) has been postulated as potent druggable cancer target. On the basis of our previous findings clearly showing that ILK transduces antisurvival signals in cells exposed ...
Settin Ahmed A E S - - 2009
Introduction: There is much controversy about the effects of chronic low dose exposure to ionizing radiation and the possible consequences particularly in occupational exposures. Objectives: This study aims at the assessment of cell cycle in healthcare workers (HCWs) occupationally exposed to radiation. Subjects and Methods. Participants in the study included ...
Niyazi Maximilian - - 2009
: Since the efficacy of a single targeted agent in combination with ionizing radiation is limited by putative treatment resistances, a rationally designed triple treatment consisting of an agonistic antibody targeting either TRAIL-R1 (mapatumumab) or TRAIL-R2 (lexatumumab), radiation and an epidermal growth factor receptor-(EGFR-)inhibiting antibody (cetuximab) was tested. : Induction ...
Albi Elisabetta - - 2009
Nuclear sphingomyelin and phosphatidylcholine metabolism is involved in the response to ultraviolet radiation treatment in different ways related to the physiological state of cells. To evaluate the effects of low levels of radiation from the stratosphere on thyroid cells, proliferating and quiescent FRTL-5 cells were flown in a stratospheric balloon ...
Halac Silvana - - 2009
This study demonstrates that UV radiation (UVR) reduces the photoprotective capacity of the diatom Phaeodactylum tricornutum by affecting xanthophyll cycle (XC) activity. The short-term reduction of photosystem II (PSII) maximum efficiency of charge separation (F(v)/F(m)) in cells exposed to UVR could be explained mainly by a reduced photoprotective capacity under ...
Flewellen, Latoya
Basic in vitro cell experiments were conducted on the P388 mouse leukaemia cell line to determine whether a supra-additive cell killing effect from combining hyperthermia with ionising radiation exists in the case of leukaemia. Methods were established to measure the cell kill, using a Coulter counter, from hyperthermia alone, radiation ...
Heo Soo-Jin - - 2009
Fucoxanthin is a carotenoid isolated from Sargassum siliquastrum and is considered to be one of major active compound of marine algae. In this study, we investigated and confirmed the protective effect of fucoxanthin on UV-B induced cell injury in human fibroblast via 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT), and comet ...
Frankenberg-Schwager Marlis - - 2008
The purpose of this study was to investigate the cell cycle-dependent role of nonhomologous DNA end joining (NHEJ), conservative homologous recombination (HR), and single-strand annealing (SSA) for the repair of simple DNA double-strand breaks (DSBs) induced by H(2)O(2)-mediated OH radicals in CHO cells. Cells of the cell lines V3 (NHEJ-deficient), ...
Groesser Torsten - - 2008
The aim of this work was to study radiation-induced bystander effects for early cytogenetic end points in various cell lines using the medium transfer technique after exposure to high- and low-LET radiation. Cells were exposed to 20 MeV/ nucleon nitrogen ions, 968 MeV/nucleon iron ions, or 575 MeV/nucleon iron ions ...
Lee Je-Jung - - 2008
Although in vitro studies have been previously conducted to determine the biological effects of radio frequency (RF) radiation, it has not yet been determined whether or not RF radiation poses a potential hazard. This study was conducted to determine whether RF radiation exposure exerts detectable effects on cell cycle distribution, ...
Dierov J - - 2009
Earlier reports have suggested that the BCR/ABL oncogene, associated with chronic myeloid leukemia, induces a mutator phenotype; however, it is unclear whether this leads to long-term changes in chromosomes and whether the phenotype is found in primary chronic myelogeneous leukemia (CML) cells. We have addressed both these issues. BCR/ABL-expressing cell ...
Vlad Roxana M - - 2008
PURPOSE: Currently, no routinely used imaging modality is available to assess tumor responses to cancer treatment within hours to days after radiotherapy. In this study, we demonstrate the preclinical application of quantitative ultrasound methods to characterize the cellular responses to cancer radiotherapy in vitro. METHODS AND MATERIALS: Three different cell ...
Belli Mauro - - 2008
This work aimed at measuring cell-killing effectiveness of monoenergetic and Spread-Out Bragg Peak (SOBP) carbon-ion beams in normal and tumour cells with different radiation sensitivity. Clonogenic survival was assayed in normal and tumour human cell lines exhibiting different radiosensitivity to X- or gamma-rays following exposure to monoenergetic carbon-ion beams (incident ...
Rea Giuseppina - - 2008
PURPOSE: Long-term space exploration requires biological life support systems capable of coping with the deleterious space environment. The use of oxygenic photosynthetic microorganisms represents an intriguing topic in this context, mainly from the point of view of food and O2 production. The aim of the present study was to assess ...
Gulliksrud Kristine - - 2008
This study aimed at developing immunohistochemical assays for different subpopulations of hypoxic cells in tumors. BALB/c-nu/nu mice bearing A-07 or R-18 tumors were given a single dose of 90 mg/kg body weight or three doses (3 h apart) of 30 mg/kg body weight of pimonidazole hydrochloride intravenously. The fraction of ...
Heidenreich W F - - 2008
Cells on the way to carcinogenesis can have a growth advantage relative to normal cells. It has been hypothesized that a radiation-induced growth advantage of these initiated cells might be induced by an increased cell replacement probability of initiated cells after inactivation of neighboring cells by radiation. Here Monte Carlo ...
Borrelli Antonella - - 2009
Organisms exposed to ionizing radiation are mainly damaged by free radicals, which are generated by the radiolysis of water contained in the cells. Recently a significant reduction of tissue injury from irradiation damage was demonstrated by using MnSOD-plasmid/liposome treatments in the protection of murine lung. In this study we show ...
Dziegielewski Jaroslaw - - 2008
Compounds that can protect cells from the effects of radiation are important for clinical use, in the event of an accidental or terrorist-generated radiation event, and for astronauts traveling in space. One of the major concerns regarding the use of radio-protective agents is that they may protect cells initially, but ...
Glaviano A - - 2009
Genomic instability is considered to be an important component in carcinogenesis. It can be caused by low-dose exposure to agents, which appear to act through induction of stress-response pathways related to oxidative stress. These agents have been studied mostly in the radiation field but evidence is accumulating that chemicals, especially ...
Markkanen Ari - - 2008
PURPOSE: Effects on DNA damage response were investigated in murine L929 cells exposed to 50 Hz magnetic fields (MF) with or without ultraviolet B (UVB, wavelength 280-320 nm) radiation or menadione (MQ). MATERIALS AND METHODS: Cells were exposed to MF at 100 or 300 microT combined with MQ (150 microM, ...
Du Guanghua - - 2008
Intracellular calcium is an important second messenger that regulates many cell functions. Recent studies have shown that calcium ions can also regulate the cellular responses to ionizing radiation. However, previous data are restricted to cells treated with low-LET radiations (X rays, gamma rays and beta particles). In this work, we ...
Huang Tai-Qin - - 2008
PURPOSE: The biological effects of exposure to mobile phone emitted radiofrequency (RF) radiation are the subject of intense study, yet the hypothesis that RF exposure is a potential health hazard remains controversial. In this paper, we monitored cellular and molecular changes in Jurkat human T lymphoma cells after irradiating with ...
Kong Tao - - 2008
Gold nanoparticles (GNPs) and modified GNPs having two kinds of functional molecules, cysteamine (AET) and thioglucose (Glu), are synthesized. Cell uptake and radiation cytotoxicity enhancement in a breast-cancer cell line (MCF-7) versus a nonmalignant breast-cell line (MCF-10A) are studied. Transmission electron microscopy (TEM) results show that cancer cells take up ...
Tomita Masanori - - 2008
Radiation-induced DNA double-stand breaks (DSBs) lead to numerous biological effects. To elucidate the molecular mechanisms involved in cellular responses to low dose and low dose-rate radiation, it is informative to clarify the roles of DSB repair related genes. In higher vertebrate cells, there are at least two major DSB repair ...
Zhang Feng - - 2008
Roscovitine has been reported to have anti-proliferative properties and is in process of undergoing clinical trials. In addition to its intrinsic anticancer properties, it has recently been suggested that roscovitine may also enhance the activity of traditional chemo- and radio- therapies in certain cancer cell lines. The purpose of this ...
Mancuso Mariateresa - - 2008
The central dogma of radiation biology, that biological effects of ionizing radiation are a direct consequence of DNA damage occurring in irradiated cells, has been challenged by observations that genetic/epigenetic changes occur in unexposed "bystander cells" neighboring directly-hit cells, due to cell-to-cell communication or soluble factors released by irradiated cells. ...
Mohlin Malin - - 2009
Nodularia spumigena is one of the dominating species during the extensive cyanobacterial blooms in the Baltic Sea. The blooms coincide with strong light, stable stratification, low ratios of dissolved inorganic nitrogen, and dissolved inorganic phosphorus. The ability of nitrogen fixation, a high tolerance to phosphorus starvation, and different photo-protective strategies ...
Richard M - - 2009
It has been shown that the response of cells to low doses of radiation is not linear and cannot be accurately extrapolated from the high dose response. To investigate possible mechanisms involved in the behaviour of cells under very low doses of radiation, a cellular automaton (CA) model was created. ...
Sauvageot Claire Marie-Elisabeth - - 2009
Glioblastoma multiforme (GBM) arises from genetic and signaling abnormalities in components of signal transduction pathways involved in proliferation, survival, and the cell cycle axis. Studies to date with single-agent targeted molecular therapy have revealed only modest effects in attenuating the growth of these tumors, suggesting that targeting multiple aberrant pathways ...
Wei Qi-Chun - - 2008
OBJECTIVE: To isolate an isogenic radioresistant cancer cell line after fractioned X-ray radiation and characterize the resistant cells. METHODS: D6 cells were exposed to repeated X-ray irradiation, and after a total dose of 5200 cGy in 8 fractions, a radioresistant monoclone D6-R was obtained. The radiosensitivity and drug sensitivity of ...
Boyd Marie - - 2008
The efficacy of radiotherapy may be partly dependent on indirect effects, which can sterilise malignant cells that are not directly irradiated. However, little is known of the influence of these effects in targeted radionuclide treatment of cancer. We determined bystander responses generated by the uptake of radioiodinated iododeoxyuridine ([*I]IUdR) and ...
Segerström Lova - - 2008
Effects of radiation on growth of two human tumour cell lines that survived a previous high dose, low dose-rate radionuclide exposure simulating intensive radionuclide therapy, were analyzed. The purpose was to investigate whether the survivors gained therapy induced changes in growth and radiation response. The U118MG, ParRes (parental resistant), and ...
Leone Stefano - - 2008
Resveratrol (3,4',5-trihydroxystilbene) is a polyphenol synthesized by a wide variety of plant species in response to injury, UV irradiation and fungal attack. Many studies have revealed a variety of resveratrol intracellular targets whose modulation gives rise to overlapping responses leading to growth arrest and death. Many authors have reported different ...
Albi E - - 2008
Intranuclear lipid metabolism modifications in relation to cell proliferation and/or apoptosis were demonstrated in hepatocytes. The aim of this study was to establish whether nuclear lipid metabolites influence cell function in different experimental models using a rat thyroid cell line (FRTL-5) treated with UV-C radiation. After UV-C irradiation cells proliferate ...
Vallotton Nathalie - - 2008
In streams and creeks, the aquatic flora is exposed to fluctuating concentrations of herbicides during and following their application. Peak concentrations of herbicides, like the chloroacetanilide S-metolachlor, are usually detected following rain events. In this study, we assessed the effect of S-metolachlor pulse exposure on the algae Scenedesmus vacuolatus. We ...
Koll Thuy T - - 2008
Inhibition of heat shock protein 90 (HSP90) leads to inappropriate processing of proteins involved in cell survival pathways. We found that HSP90 inhibitor, 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (DMAG), is synergistic with radiation for non-small cell lung cancer cell lines, NCI-H460 and A549. To establish the optimal schedule for this combination, cells were radiated ...
Susanne Burdak-Rothkamm, Kai Rothkamm, ...
Ionising radiation-induced effects in nontargeted bystander cells may play an important role in low-dose cancer risk. Here, we briefly review the experimental systems used for bystander studies, the initiation and intercellular transmission of bystander signals and response mechanisms in recipient cells. Recent evidence that implicates the histone 2A variant X ...
Partridge Mike - - 2008
A cellular Monte Carlo model describing radiation damage and repair in normal epithelial tissues is presented. The deliberately simplified model includes cell cycling, cell motility and radiation damage response (cell cycle arrest and cell death) only. Results demonstrate that the model produces a stable equilibrium system for mean cell cycle ...
Iwabuchi Kuniyoshi - - 2008
Non-homologous end joining (NHEJ) plays a major role in the repair of ionizing radiation-induced DNA double-strand breaks (DSBs), especially during the G1-phase of the cell cycle. Using a flow cytometric cell sorter, we fractionated G1- and S/G2-phase cells based on size to assess the DSB-repair activity in NHEJ factor-deficient DT40 ...
Uma Devi P - - 2008
Withaferin A (WA), a plant withanolide, has shown significant radiosensitizing effect in vitro and in vivo. Inhibition of DNA repair has been suggested as a mechanism of radiosensitization by WA. To test this, the effect of withaferin A on survival of DT40 chicken B-lymphocyte cell line and its repair deficient ...
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