Search Results
Results 401 - 450 of 1946
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Maxson Michelle E - - 2007
We present a new method to measure capsule size in the human fungal pathogen Cryptococcus neoformans that avoids the limitations and biases inherent in India ink measurements. The method is based on the use of gamma-radiation, which efficiently releases the capsule from the cell. By comparing the volume of irradiated ...
Kim Hooi-Sung - - 2006
A dye-sensitized solar cell was constructed using a porphyrin photosensitizer and, in place of the usual iodide redox system, a solution in aniline solvent containing lithium perchlorate electrolyte, camphorsulfonic acid, and poly(ethylene oxide) copolymer. Irradiation generated polyaniline within the cell, initially following a proposed photoelectropolymerization mechanism, and eventually operating as ...
Vantieghem Katleen K Laboratory for Experimental Medicine and Endocrinology (LEGENDO), Gasthuisberg, Katholieke Universiteit Leuven, Leuven, - - 2006
Epidermal keratinocytes are able to produce 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] and induce vitamin D activity upon UVB irradiation. To find out whether this property is keratinocyte specific, we investigated this characteristic in two other cell types, namely intestinal CaCo-2 cells and the macrophage-like differentiated THP-1 cells. THP-1 macrophages and preconfluent CaCo-2 ...
Shao Chunlin - - 2006
Bystander responses have been reported to be a major determinant of the response of cells to radiation exposure at low doses, including those of relevance to therapy. This study investigated the role of changes in calcium levels in bystander responses leading to chromosomal damage in nonirradiated T98G glioma cells and ...
Boutis Anastasios - - 2006
Gamma-irradiation leads to apoptosis and cell cycle arrest in eukaryotic cells. Olomoucine is a novel purine analog acting as a cyclin-dependent kinase inhibitor. The effects of olomoucine in gamma-irradiation mediated cell growth inhibition and apoptosis were studied in the Raji cell line (Burkitt's lymphoma). Gamma-irradiation caused a G2 arrest, increasing ...
Kato Takamitsu A - - 2006
We have investigated the use of the gamma-H2AX assay, reflecting the presence of DNA double-strand breaks, as a possible means for identifying individuals who are mildly hypersensitive to ionizing radiation, such as some ATM heterozygotes. We compared levels of gamma-H2AX foci after irradiation in cells from six apparently normal individuals ...
Godthelp Barbara C - - 2006
Fanconi anemia (FA) is an inherited cancer-susceptibility disorder, characterized by genomic instability and hypersensitivity to DNA cross-linking agents. The discovery of biallelic BRCA2 mutations in the FA-D1 complementation group allows for the first time to study the characteristics of primary BRCA2-deficient human cells. FANCD1/BRCA2-deficient fibroblasts appeared hypersensitive to mitomycin C ...
You Youngjae - - 2006
A core-modified porphyrin, 5-phenyl-10,15-bis(carboxylatomethoxyphenyl)-20-(2-thienyl)-21,23-dithiaporphyrin (IY69) was studied in vitro for photodynamic activity under a variety of experimental protocols. Variables included the cell line (the rodent mammary tumor cell line R3230AC or the human breast cancer cell line MCF-7), light fluence, time of exposure of the cell cultures to IY69, and ...
Jantová Sona - - 2006
The present study demonstrates photoinduced generation of superoxide anion radical and singlet oxygen upon UVA irradiation of berberine chloride, and its cytotoxic/phototoxic effects on murine fibroblast non-cancer NIH-3T3 and Ehrlich ascites carcinoma (EAC) cells. The EPR spectra monitored upon photoexcitation of aerated solutions of berberine evidenced the efficient activation of ...
Hayashi Tetsutaro - - 2006
The remarkable capability of planarian regeneration is mediated by a group of adult stem cells referred to as neoblasts. Although these cells possess many unique cytological characteristics (e.g. they are X-ray sensitive and contain chromatoid bodies), it has been difficult to isolate them after cell dissociation. This is one of ...
Ohnishi Ken - - 2006
PURPOSE: We examined the effects of a heat shock protein (hsp) inhibitor, N-formyl-3, 4-methylenedioxy-gamma-butyrolactam (KNK437), on the radiosensitivity of human glioblastoma cells (A-172). MATERIALS AND METHODS: Effects of KNK437 on radiosensitivity and cell cycle regulation were examined using colony formation assays, flow cytometry analysis and Western blot analysis. KNK437 was ...
Liu Quanhong - - 2006
The cytotoxic effect of PPIX on isolated sarcoma 180 cells induced by ultrasound was investigated. Tumor cells suspended in air-saturated PBS (pH 7.2) were exposed to ultrasound at 2.2 MHz for up to 60s in the presence and absence of protoporphyrin IX disodium salt (PPIX). The viability of cells was ...
Beneduci A - - 2007
In the present study we compared the proliferation behavior, the ultrastructural morphology and the glycolitic metabolism of K562 cells irradiated by low-power wide-band millimeter waves, with those of sham-exposed K562 cells (control), maintained in the same culture conditions. The gigaHertz radiation treatments, performed between 53-78 10(9) Hz, induced a noticeable ...
Bromley Regina - - 2006
In this study we have investigated a spatial distribution of cell growth after their irradiation using a modulated x-ray intensity pattern. An A549 human non-small cell lung cancer cell line was grown in a 6-well culture. Two of the wells were the unirradiated control wells, whilst another two wells were ...
Kimura Shinzo - - 2006
Ionizing radiation (IR) is the most enigmatic of genotoxic stress inducers in our environment that has been around from the eons of time. IR is generally considered harmful, and has been the subject of numerous studies, mostly looking at the DNA damaging effects in cells and the repair mechanisms therein. ...
Wang Rui-Juan RJ Institute of Radiation Medicine, Academy of Military Medical Sciences, Beijing 100850, - - 2006
To explore the effect of recombinant human interleukin-11 (rhIL-11) on the expressions of interleukin-11 receptor alpha-chain (IL-11Ralpha) and an additional signal transducer glycoprotein 130 (gp130) in intestinal epithelium cell line-6 (IEC-6) after neutron irradiation. Cultured IEC-6 cells were exposed to 4.0Gy neutron and treated with 100 ng/mL rhIL-11 12 h ...
Toussaint Martin - - 2006
The sensitivity of yeast Saccharomyces cerevisiae to DNA damaging agents is better represented when cells are grown in liquid media than on solid plates. However, systematic assessment of several strains that are grown in different conditions is a cumbersome undertaking. We report an assay to determine cell growth based on ...
Liu Feng - - 2006
BACKGROUND: Cockayne syndrome (CS) is a rare human genetic disorder characterized by increased UV sensitivity, developmental abnormalities and premature aging. Cells isolated from individuals with CS have a defect in transcription-coupled DNA repair. Despite the repair defect, there is no any increased risk of spontaneous or UV-induced cancer for CS ...
Singh Rakesh Kumar - - 2006
Nucleotide excision repair (NER) is the most versatile and universal pathway of DNA repair that is capable of repairing virtually any damages other than a double strand break (DSB). This pathway has been shown to be inducible in several systems. However, question of a threshold and the nature of the ...
Petrović Ivan - - 2006
PURPOSE: To measure the ability of protons and gamma-rays to effect cell viability and cell survival of human HTB140 melanoma cells. MATERIALS AND METHODS: Exponentially growing HTB140 cells were irradiated close to the Bragg peak maximum of the 62 MeV protons or with 60Co gamma-rays with single doses, ranging from ...
Medrado Alena P - - 2006
Little is known about the action of laser rays on normal adipose cells. The present study attempts to observe the behavior of fatty cells submitted to laser therapy. Dorsal fat pads of normal adult rats were submitted to low-level laser irradiation applied locally through intact skin, with four different dose ...
Mortensen M W - - 2006
In this paper we present surface modification strategies of boron carbide nanoparticles, which allow for bioconjugation of the transacting transcriptional activator (TAT) peptide and fluorescent dyes. Coated nanoparticles can be translocated into murine EL4 thymoma cells and B16 F10 malignant melanoma cells in amounts as high as 0.3 wt. % ...
Masuda Kazuhiko - - 2006
The LEC rat is reported to exhibit hypersensitivity to X-irradiation, deficiency in DNA double-strand break repair, and radio-resistant DNA synthesis. This character of the LEC rat has been thought to be due to abnormal G1 arrest in cells after X-irradiation. In this report, we re-investigated the effect of X-irradiation on ...
Leatherbarrow Emma L EL DNA Damage Group, Radiation and Genome Stability Unit, Medical Research Council, Harwell, Oxfordshire, - - 2006
To investigate quantitatively the induction and rejoining of DNA double strand breaks (DSB) in V79-4 and xrs-5 Chinese hamster cells and HF19 human fibroblast cells, using the phosphorylation of the histone protein H2AX (gamma-H2AX) as an indicator of DSB, exposed to low doses of either low linear energy transfer (LET) ...
Ukai Akiko - - 2006
DNA polymerase theta (Poltheta) is a family A polymerase that contains an intrinsic helicase domain. To investigate the function of Poltheta in mammalian cells, we have inactivated its polymerase activity in CH12 mouse B lymphoma cells by targeted deletion of the polymerase core domain that contains the catalytic aspartic acid ...
Seotsanyana-Mokhosi Itumeleng - - 2006
The photodynamic activity of water soluble mixed sulfonated metallophthalocyanines complexes: GePcSmix, SnPcSmix and SiPcSmix on human oesophageal carcinoma (SNO) cells are reported, and compared with the activity of the unmetallated H2PcSmix and of the newly synthesized water soluble adjacently substituted binaphthalo phthalocyanine (complex 3). The alkaline phosphate (ALP) showed damage ...
Fuentes J L - - 2006
This work was aimed to evaluate genotoxicity and antigenotoxicity activity against gamma-rays of a tannin fraction obtained from barks of Pinus caribaea, as well as to elucidate the antigenotoxic mechanisms involved in radioprotection by using different approaches as pre-, co- and post-irradiation cell treatments with plant extract. The tannin fraction ...
Müller Werner E G - - 2006
Until now the bystander effect had only been described in vertebrates. In the present study the existence of this effect has been demonstrated for the phylogenetically oldest metazoan phylum, the Porifera. We used the demosponge Suberites domuncula for the experiments in the two-chamber-system. The lower dish contained irradiated "donor" cells ...
Chaudhry M Ahmad - - 2006
In cell populations exposed to ionizing radiation, the biological effects occur in a much larger proportion of cells than are estimated to be traversed by radiation. It has been suggested that irradiated cells are capable of providing signals to the neighboring unirradiated cells resulting in damage to these cells. This ...
Bowler Deborah A - - 2006
Communication between irradiated and unirradiated (bystander) cells can result in responses in unirradiated cells that are similar to responses in their irradiated counterparts. The purpose of the current experiment was to test the hypothesis that bystander responses will be similarly induced in primary murine stem cells under different cell culture ...
DeVeaux Linda C - - 2006
Radiation-induced bystander effects have been seen in mammalian cells from diverse origins. These effects can be transmitted through the medium to cells not present at the time of irradiation. We have developed an assay for detecting bystander effects in the unicellular eukaryote, the fission yeast Schizosaccharomyces pombe. This assay allows ...
Newman David J - - 2006
The bystander effect is a process whereby the medium in which cells are irradiated at very low levels is presumed to contain a "low molecular weight" entity that will induce cell death and/or genetic changes in fresh mammalian cells when they are incubated in the medium. Following discussions at a ...
Alvarez M Gabriela - - 2006
The photokilling activity of a porphyrin-C(60) (P-C(60)) dyad was evaluated on a Hep-2 human larynx-carcinoma cell line. This study represents the first evaluation of a dyad, with high capacity to form a photoinduced charge-separated state, to act as agent to inactivate cells by photodynamic therapy (PDT). Cell treatment was carried ...
Di Pietro C - - 2006
Due to their ballistic precision, apoptosis induction by protons could be a strategy to specifically eliminate neoplastic cells. To characterize the cellular and molecular effects of these hadrons, we performed dose-response and time-course experiments by exposing different cell lines (PC3, Ca301D, MCF7) to increasing doses of protons and examining them ...
Daudin L - - 2006
A single ion hit facility is being developed at the Pierre Süe Laboratory (LPS) since 2004. This set-up will be dedicated to the study of ionising radiation effects on living cells, which will complete current research conducted on uranium chemical toxicity on renal and osteoblastic cells. The study of the ...
Dean David A - - 2006
INTRODUCTIONThis protocol describes a method for plating cells for microinjection onto etched coverslips. The coverslips for microinjection must be marked so that microinjected cells can be identified at time points after injection. A procedure for etching coverslips is given below; alternatively, pre-etched coverslips can be purchased at slightly higher cost.
Djordjevic Bozidar - - 2006
We have developed a system of mixed aggregates of cultured cells, to model in situ cell interactions. This three-dimensional (3D) system of floating cell aggregates, termed spheroids for their round shape, enables one to monitor their growth in both size and number of constituent clonogens and to measure survival curves ...
Hawkins Denise H - - 2006
BACKGROUND: In medicine, lasers have been used predominantly for applications, which are broadly termed low level laser therapy (LLLT), phototherapy or photobiomodulation. This study aimed to establish cellular responses to Helium-Neon (632.8 nm) laser irradiation using different laser fluences (0.5, 2.5, 5, 10, and 16 J/cm(2)) with a single exposure ...
Veselov O - - 2006
In recent years, a single ion hit facility has been constructed at the IFJ ion microprobe. The setup is used for the precise irradiations of living cells by a controlled number of ions. Investigations of such type have two very important requirements: (1) cells must be examined in their natural ...
Greif K - - 2006
The PTB microbeam is routinely used for the irradiation of living cells using protons (1-20 MeV) and alpha particles (1-28 MeV). The beam diameter is approximately 2 microm (fwhm), achieved by focussing, resulting in an excellent energy resolution and practically no scattered particles. Recently, an electrostatic beam scanner was added ...
Shinbo Y - - 2006
DJ-1 is a multifunctional protein that plays roles in transcriptional regulation and antioxidative stress, and loss of its function is thought to result in the onset of Parkinson's disease (PD). Here, we report that DJ-1 was sumoylated on a lysine residue at amino-acid number 130 (K130) by PIASxalpha or PIASy. ...
Mothersill C - - 2006
Radiation-induced bystander factors have been shown to be more toxic if they are from medium harvested from irradiated repair-deficient cells. The aim of this study was to test the hypothesis that the radiosensitivity of repair-proficient cells can be increased by exposing them to medium-borne factors harvested from sensitive cells and ...
Sugimoto Tomoko - - 2006
PURPOSE: To investigate positional effects of radiation with an energetic heavy-ion microbeam on germline cells using an experimental model metazoan Caenorhabditis elegans. MATERIALS AND METHODS: The germline cells were irradiated with raster-scanned broad beam or collimated microbeam of 220 MeV 12C5+ particles delivered from the azimuthally varying field (AVF) cyclotron, ...
Tanno Y - - 2006
Although the highest radiosensitivity of cells in the M phase among the other cell phases, such as the G(1), S and G(2) phases, has been known, the exact mechanism of radiosensitivity in mitotic cells remains unclear. Recently, mitotic arrest caused by DNA-damaging reagents has been shown, and the molecular mechanism ...
Endo K - - 2006
Micro-proton-induced X-ray emission (Micro-PIXE) was applied to determine inter- and intracellular distribution of boron (10B) and gadolinium (157Gd), the capture atoms used to kill tumor cells in neutron capture therapy (NCT). Cultured 9L gliosarcoma cells on Mylar film were exposed to sodium borocaptate (BSH) and gadobenate dimeglumine (Gd-BOPTA). To analyze ...
Clark Imran B - - 2006
Efficient delivery of compounds and macromolecules into living cells is essential in many fields including basic research, applied drug discovery, and clinical gene therapy. Unfortunately, current delivery methods, such as cationic lipids and electroporation, are limited by the types of macromolecules and cells that can be employed, poor efficiency, and/or ...
Smilenov L B - - 2006
Radiation-induced bystander effect has been well documented. However, the mechanisms are poorly understood. How we incorporate this effect into the classical models of risk assessment remains an open question. Here, the induction of bystander effect was studied by assessing DNA double-strand break (DSB) formation in situ with the rapid and ...
Góes E G - - 2006
BACKGROUND: To identify the most appropriate dose for the prevention of transfusion-associated graft-versus-host disease, the radiosensitivity of T cells has been determined in blood bags irradiated with X-rays produced by a linear accelerator and gamma rays derived from the cesium-137 source of a specific irradiator. In this study, the influence ...
Tanaka T - - 2006
PURPOSE OF INVESTIGATION: 5-Fluorouracil (5FU) is frequently used in concurrent chemoradiotherapy for patients with advanced cervical cancer, although its optimal chemoradiotherapy protocol has not yet been established. In search of an optimal chemoradiotherapy protocol, some in vitro experiments were carried out. METHODS: The radiosensitive human cervical squamous cell carcinoma cell ...
Lowery Amanda R - - 2006
Consisting of a silica core surrounded by a thin gold shell, nanoshells possess an optical tunability that spans the visible to the near infrared (NIR) region, a region where light penetrates tissues deeply. Conjugated with tumor-specific antibodies, NIR-absorbing immunonanoshells can preferentially bind to tumor cells. NIR light then heats the ...
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