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Sample records for ray parenchyma cells

  1. HURTLE CELLS IMMUNOHISTOCHEMICAL ACTIVITIES IN HASHIMOTO THYROIDITIS PARENCHYMA.

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    Tsagareli, Z; Kvachadze, T; Melikadze, E; Metreveli, L; Nikobadze, E; Gogiashvili, L

    2016-11-01

    The present study was designed to evaluate the participation and utility of Hǘrtle cells morphological requirment and transformation under Hashimoto autoimmune thyroiditis versus Riedel´s struma. Several markers have been evaluated to detect induced activities of Hǘrtle cells. Study subject - specimens (tissue fragments) collected from TG surgery (thyroidectomy) for mollecular (receptor) diagnosis of Hǘrtle cells activities using routine histological and immunohistochemical samples. 89 cases were selected in Hashimoto thyroiditis diagnosis with Hǘrtle cells history (adenoma and adenomatous grouth of oncocytes). Markers as: TSH receptors, TTF-1, S-100 protein, also anti-TPO and anti-TG levels in blood plasm were detected. It was shown that solid cell claster-nests like agregation of oncocytes and adenomatous growth foci in parafollicular areas with anti-TPO and anti-TG antibodies levels arising while Riedel´s struma shown only large intra- and extra glandular inflammatory proliferative fibrosing process. Large positive expression of TTF-1 and S-100 protein and the negative reaction of TSH receptor factor suggest that Thyroid parenchyma disorganization and mollecular biological atypia with Hǘrtle cells are proceses due to hypothyreoidismus, as well as neuroectodermal cells prominent activities in 70% of Hashimoto cases.

  2. CT differentiation of renal tumor invading parenchyma and pelvis: renal cell carcinoma vs transitional cell carcinoma

    International Nuclear Information System (INIS)

    Lee, Chang Hee; Cho, Seong Beum; Park, Cheol Min; Cha, In Ho; Chung, Kyoo Byung

    1994-01-01

    The differentiation between renal cell carcinoma(RCC) and transitional cell carcinoma(TCC) is important due to the different methods of treatment and prognosis. But occasionally it is difficult to draw a distinction between the two diseases when renal parenchyma and renal collecting systems are invaded simultaneously. We reviewed CT scans of 37 cases of renal cell carcinoma and 12 cases of transitional cell carcinoma which showed involvement of renal parenchyma and renal sinus fat on CT. Retrospective analysis was performed by 3 abdominal radiologists. Check points were renal contour bulging or reinform shape, location of mass center, intact parenchyma overlying the tumor, cystic change, calcification, LN metastasis, vessel invasion, and perirenal extention. There were renal contour bulging due to the tumor mass in 33 out of 37 cases of renal cell carcinoma, where a and nine of 12 cases of transitional cell carcinoma maintained the reinform appearance. This is significant statiscal difference between the two(P<0.005). Center of all TCCs were located in the renal sinus, and 24 out of 35 cases of RCC were located in the cortex(P<0.005). Thirty-six out of 37 cases of RCC lost the overlying parenchyma, where as 4 out of 9 cases of well enhanced TCC had intact overlying parenchyma(P<0.005) RCC showed uptic change within the tumor mags in 31 cases which was significanity higher than the 4 cases in TCC(P<0.05). CT findings of renal cell carcinoma are contour bulging, peripheral location, obliteration of parenchyma, and cystic change. Findings of transitional cell carcinoma are reinform appearance, central location within the kidney, intact overlying parenchyma, and rare cystic change

  3. Developmental characteristics of parenchyma and fiber cells and their secondary wall deposition in fargesia yunnanensis

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    Wang, S.G.; Zhan, H.; Wan, C.B.; Lin, S.Y.

    2017-01-01

    The aim of this study is to describe and analyse the morphological characteristics of nuclei and the secondary wall deposition in parenchyma and fiber cells during the whole bamboo growth cycle from shoots to old culms, with a further purpose to assess the developmental differences between fibers and parenchyma cells and analyze the secondary wall deposition mechanism. Initially the fiber wall thickness was less than the parenchyma cell thickness in young shoots, but increased significantly after 1 year. Fibers elongated earlier than both their nuclei and parenchyma cells. Fiber nuclei also elongated and presented the spindle shape in longitudinal section. The formation and elongation of long cells were involved in the fast elongation of internodes. In mature culms, the ways of secondary wall deposition for fibers depended on their diameter and positions. Large diameter fibers usually had more cell wall layers than narrow fibers. (author)

  4. Development of fibre and parenchyma cells in the bamboo Phyllostachys viridi-glaucescens

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    Crow, E.

    2000-02-01

    The development of the shoot apex and the ontogeny of fibre and parenchyma cells in elongating shoots of the bamboo Phyllostachys viridi-glaucescens (Carr.) Riv. and Riv., seen under the light microscope is described. Fibre cells differentiated from cells of the procambium, whilst the parenchyma cells differentiated from cells of the primary thickening meristem which surround the procambium strands. Three stages of early fibre and parenchyma cell development were identified and these are referred to in subsequent studies of cell wall development. The cytology of developing internodal fibre and parenchyma cells seen under the transmission electron microscope (TEM) is described. There were few ultrastructural features to distinguish the two cell types. Thiery's PATAg test was performed to identify organelles which may be associated with the synthesis of polysaccharides destined for the cell wall. The ultrastructural results are discussed in terms of the process of cell wall deposition. Observations were made of cytoskeletal elements using indirect immunofluorescence techniques. Orientations of cortical microtubules differed from those of the microfilaments throughout early development. Filaments on the inner walls of cells seen under the conventional scanning electron microscope (SEM) were cytoskeletal-like in their orientation and form. Immunogold labelling techniques were performed in an attempt to confirm their identity. Staining with safranin and alcian blue allowed an anatomical description of wall development in fibre and parenchyma cells. These studies were coupled with observations using polarizing optics where cellulose microfibril orientations of the primary and secondary wall layers were established. The field emission scanning electron microscope (FESEM) was used to describe microfibril orientations seen on the inner wall of developing and maturing fibre and parenchyma cells. Chemical extraction of wall matrix materials was necessary for maturing tissue

  5. Parenchyma cell wall structure in twining stem of Dioscorea balcanica

    Czech Academy of Sciences Publication Activity Database

    Radosavljević, J.S.; Pristov, J.B.; Mitrović, A.Lj.; Steinbach, Gabor; Mouille, G.; Tufegdžić, S.; Maksimović, V.; Mutavdžić, D.; Janošević, D.; Vuković, M.; Garab, G.; Radotić, K.

    2017-01-01

    Roč. 24, č. 11 (2017), s. 4653-4669 ISSN 0969-0239 R&D Projects: GA MŠk(CZ) ED2.1.00/19.0392 Institutional support: RVO:61388971 Keywords : Cell wall * Cellulose fibril order * Dioscorea balcanica Kosanin Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 3.417, year: 2016

  6. Organization of the cytoplasmic reticulum in the central vacuole of parenchyma cells in Allium cepa L.

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    Tomasz J. Wodzicki

    2015-01-01

    Full Text Available An elaborate and complex cytoplasmic reticulum composed of fine filaments and lamellae ranging from 0.1 to 4 microns in size is revealed by viewing the central vacuole of onion bulb parenchyma cells with the scanning election microscope. The larger cytoplasmic strands, visible with the light microscope, are composed of numerous smaller filaments (some tubular which might explain the observed bidirectional movement of particles in these larger strands. The finely divided cytoplasmic network of filaments is continuous with the parietal cytoplasm inclosing the vacuolar sap. In these highly vacuolated cells the mass of the protoplast is in the form of an intravacuolar reticulum immersed in the cell sap. The probable significance of the vacuolar sap in relation to physiological processes of the cell is discussed.

  7. Compositional analysis of Chinese water chestnut (Eleocharis dulcis) cell-wall material from parenchyma, epidermis, and subepidermal tissues.

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    Grassby, Terri; Jay, Andrew J; Merali, Zara; Parker, Mary L; Parr, Adrian J; Faulds, Craig B; Waldron, Keith W

    2013-10-09

    Chinese water chestnut (Eleocharis dulcis (Burman f.) Trin ex Henschel) is a corm consumed globally in Oriental-style cuisine. The corm consists of three main tissues, the epidermis, subepidermis, and parenchyma; the cell walls of which were analyzed for sugar, phenolic, and lignin content. Sugar content, measured by gas chromatography, was higher in the parenchyma cell walls (931 μg/mg) than in the subepidermis (775 μg/mg) or epidermis (685 μg/mg). The alkali-extractable phenolic content, measured by high-performance liquid chromatography, was greater in the epidermal (32.4 μg/mg) and subepidermal cell walls (21.7 μg/mg) than in the cell walls of the parenchyma (12.3 μg/mg). The proportion of diferulic acids was higher in the parenchyma. The Klason lignin content of epidermal and subepidermal cell walls was ~15%. Methylation analysis of Chinese water chestnut cell-wall polysaccharides identified xyloglucan as the predominant hemicellulose in the parenchyma for the first time, and also a significant pectin component, similar to other nongraminaceous monocots.

  8. Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis.

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    Lovato, Laura; Willis, Simon N; Rodig, Scott J; Caron, Tyler; Almendinger, Stefany E; Howell, Owain W; Reynolds, Richard; O'Connor, Kevin C; Hafler, David A

    2011-02-01

    In the central nervous system of patients with multiple sclerosis, B cell aggregates populate the meninges, raising the central question as to whether these structures relate to the B cell infiltrates found in parenchymal lesions or instead, represent a separate central nervous system immune compartment. We characterized the repertoires derived from meningeal B cell aggregates and the corresponding parenchymal infiltrates from brain tissue derived primarily from patients with progressive multiple sclerosis. The majority of expanded antigen-experienced B cell clones derived from meningeal aggregates were also present in the parenchyma. We extended this investigation to include 20 grey matter specimens containing meninges, 26 inflammatory plaques, 19 areas of normal appearing white matter and cerebral spinal fluid. Analysis of 1833 B cell receptor heavy chain variable region sequences demonstrated that antigen-experienced clones were consistently shared among these distinct compartments. This study establishes a relationship between extraparenchymal lymphoid tissue and parenchymal infiltrates and defines the arrangement of B cell clones that populate the central nervous system of patients with multiple sclerosis.

  9. Ultrastructural changes in aster yellows phytoplasma affected Limonium sinuatum Mill. plants II. Pathology of cortex parenchyma cells

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    Anna Rudzińska-Langwald

    2014-01-01

    Full Text Available In Limonium sinuatum Mill, plants with severe symptoms of aster yellows infection phytoplasmas were present not only in the phloem but also in some cortex parenchymas cells. These parenchyma cells were situated at some distance from the conducting bundles. The phytoplasmas were observed directly in parenchyma cells cytoplasm. The number of phytoplasmas present in each selected cell varies. The cells with a small number of phytoplasmas show little pathological changes compared with the unaffected cells of the same zone of the stem as well with the cells of healthy plants. The cells filled with a number of phytoplasmas had their protoplast very much changed. The vacuole was reduced and in the cytoplasm a reduction of the number of ribosomes was noted and regions of homogenous structure appeared. Mitochondria were moved in the direction of the tonoplast and plasma membrane. Compared to the cells unaffected by phytoplasma, the mitochondria were smaller and had an enlarged cristae internal space. The chloroplasts from affected cells had a very significant reduction in size and the tylacoids system had disappeared. The role of these changes for creating phytoplasma friendly enviroment is discused.

  10. Primary extranodal marginal zone B-cell lymphoma with AL amyloidosis in cerebral parenchyma in an immunocompetent patient

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    Tadashi Terada, M.D., Ph.D.

    2015-09-01

    Full Text Available Herein reported is an extremely rare case of primary MALT lymphoma of cerebral parenchyma. A 79-year-old man presented with paresis. Imaging modalities identified a tumor measuring 3 cm in diameter in right cerebral parenchyma. An operation completely resected the tumor. Macroscopically, the tumor was well defined, but showed mild infiltrative features. Histologically, the tumor showed proliferation of small atypical lymphocytes separated by fibrous septae with AL amyloid depositions. No apparent plasma cell differentiation was seen. The tumor cells showed monotonous appearances with hyperchromatic nuclei but without nucleoli and nuclear indentations. Immunoblastic cells were scattered. Immunohistochemically, tumor cells were positive for vimentin, CD45, CD20, CD79α, bcl-2, CD3 (focal, CD45RO (focal, CD5 (focal, CD10, CD23, bcl-6, CD138, p53, and Ki-67 (labeling = 27%. The immunoblastic cells were positive for CD30. The lymphoid cells were negative for Epstein–Barr virus (EBV-related molecules of EBV latent membrane protein-1 (LMP-1 and EBV early RNAs (EBER. They were also negative for cytokeratins AE 1/3 and CAM5.2, cyclin D1, CD34, GFAP, α-smooth muscle actin, and S100 protein. Because of the heterogeneity of tumor cells and positive AL amyloid deposition, the author diagnosed it as primary MALT lymphoma. The patient is now free from tumors. Differential diagnosis was discussed.

  11. Phloem as Capacitor: Radial Transfer of Water into Xylem of Tree Stems Occurs via Symplastic Transport in Ray Parenchyma[OPEN

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    Renard, Justine; Tjoelker, Mark G.; Salih, Anya

    2015-01-01

    The transfer of water from phloem into xylem is thought to mitigate increasing hydraulic tension in the vascular system of trees during the diel cycle of transpiration. Although a putative plant function, to date there is no direct evidence of such water transfer or the contributing pathways. Here, we trace the radial flow of water from the phloem into the xylem and investigate its diel variation. Introducing a fluorescent dye (0.1% [w/w] fluorescein) into the phloem water of the tree species Eucalyptus saligna allowed localization of the dye in phloem and xylem tissues using confocal laser scanning microscopy. Our results show that the majority of water transferred between the two tissues is facilitated via the symplast of horizontal ray parenchyma cells. The method also permitted assessment of the radial transfer of water during the diel cycle, where changes in water potential gradients between phloem and xylem determine the extent and direction of radial transfer. When injected during the morning, when xylem water potential rapidly declined, fluorescein was translocated, on average, farther into mature xylem (447 ± 188 µm) compared with nighttime, when xylem water potential was close to zero (155 ± 42 µm). These findings provide empirical evidence to support theoretical predictions of the role of phloem-xylem water transfer in the hydraulic functioning of plants. This method enables investigation of the role of phloem tissue as a dynamic capacitor for water storage and transfer and its contribution toward the maintenance of the functional integrity of xylem in trees. PMID:25588734

  12. A particle-based model to simulate the micromechanics of single-plant parenchyma cells and aggregates

    International Nuclear Information System (INIS)

    Van Liedekerke, P; Tijskens, E; Smeedts, B; Ramon, H; Ghysels, P; Samaey, G; Roose, D

    2010-01-01

    This paper is concerned with addressing how plant tissue mechanics is related to the micromechanics of cells. To this end, we propose a mesh-free particle method to simulate the mechanics of both individual plant cells (parenchyma) and cell aggregates in response to external stresses. The model considers two important features in the plant cell: (1) the cell protoplasm, the interior liquid phase inducing hydrodynamic phenomena, and (2) the cell wall material, a viscoelastic solid material that contains the protoplasm. In this particle framework, the cell fluid is modeled by smoothed particle hydrodynamics (SPH), a mesh-free method typically used to address problems with gas and fluid dynamics. In the solid phase (cell wall) on the other hand, the particles are connected by pairwise interactions holding them together and preventing the fluid to penetrate the cell wall. The cell wall hydraulic conductivity (permeability) is built in as well through the SPH formulation. Although this model is also meant to be able to deal with dynamic and even violent situations (leading to cell wall rupture or cell–cell debonding), we have concentrated on quasi-static conditions. The results of single-cell compression simulations show that the conclusions found by analytical models and experiments can be reproduced at least qualitatively. Relaxation tests revealed that plant cells have short relaxation times (1 µs–10 µs) compared to mammalian cells. Simulations performed on cell aggregates indicated an influence of the cellular organization to the tissue response, as was also observed in experiments done on tissues with a similar structure

  13. Wall ingrowth deposition in phloem parenchyma transfer cells in Arabidopsis: Heteroblastic variations and a potential role in pathogen defence.

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    Nguyen, Suong T T; McCurdy, David W

    2017-06-03

    Transfer cell (TCs) develop unique wall ingrowth networks which amplify plasma membrane surface area and thus maximize nutrient transporter density at key anatomic sites for nutrient exchange within plants and their external environment. These sites fall into 4 main groups corresponding to 4 categories of trans-membrane flux: absorption/secretion of solutes from or to the external environment, and absorption/secretion of solutes from or to internal, extra-cytoplasmic compartments. Research on TC biology over recent decades has demonstrated correlations between wall ingrowth deposition in TCs and enhanced transport capacity in many major agricultural species such as pea, fava bean, cotton and maize. Consequently, there is general consensus that the existence of wall ingrowth morphology implies an augmentation in membrane transport capacity. However, this may not be entirely applicable for phloem parenchyma (PP) TCs in Arabidopsis. Our recent survey of PP TC abundance and distribution in Arabidopsis veins indicated that PP TC development reflects heteroblastic status. A consequence of this observation is the suggestion that PP TCs, or at least wall ingrowth deposition in these cells, potentially act as a physical barrier to defend access of invading pathogens to sugar-rich sieve elements rather than solely in facilitating the export of photoassimilate from collection phloem in leaves.

  14. Effective segmentation of fresh post-mortem murine lung parenchyma in phase contrast X-ray tomographic microscopy images

    International Nuclear Information System (INIS)

    Oikonomidis, Ioannis Vogiatzis; Cremona, Tiziana P; Schittny, Johannes C; Lovric, Goran; Arcadu, Filippo; Stampanoni, Marco

    2017-01-01

    The acinus represents the functional unit of the mammalian lung. It is defined as the small tree of gas-exchanging airways, which is fed by the most distal purely conducting airway. Different hypotheses exist on how the fine structure of the acinus changes during ventilation and development. Since in classical 2-dimensional (2D) sections of the lung the borders of the acini are not detectable, every study of acini requires 3-dimensional (3D) datasets. As a basis for further studies of pulmonary acini we imaged rodent lungs as close to life as possible using phase contrast synchrotron radiation-based X-ray tomographic microscopy (SRXTM), and developed a protocol for the segmentation of the alveolar septa. The method is based on a combined multilevel filtering approach. Seeds are automatically defined for separate regions of tissue and airspace during each 2D filtering level and then given as input to a 3D random walk segmentation. Thus, the different types of artifacts present in the images are treated separately, taking into account the sample’s structural complexity. The proposed procedure yields high-quality 3D segmentations of acinar microstructure that can be used for a reliable morphological analysis. (paper)

  15. Antigen-Induced but Not Innate Memory CD8 T Cells Express NKG2D and Are Recruited to the Lung Parenchyma upon Viral Infection.

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    Grau, Morgan; Valsesia, Séverine; Mafille, Julien; Djebali, Sophia; Tomkowiak, Martine; Mathieu, Anne-Laure; Laubreton, Daphné; de Bernard, Simon; Jouve, Pierre-Emmanuel; Ventre, Erwan; Buffat, Laurent; Walzer, Thierry; Leverrier, Yann; Marvel, Jacqueline

    2018-05-15

    The pool of memory-phenotype CD8 T cells is composed of Ag-induced (AI) and cytokine-induced innate (IN) cells. IN cells have been described as having properties similar to those of AI memory cells. However, we found that pathogen-induced AI memory cells can be distinguished in mice from naturally generated IN memory cells by surface expression of NKG2D. Using this marker, we described the increased functionalities of AI and IN memory CD8 T cells compared with naive cells, as shown by comprehensive analysis of cytokine secretion and gene expression. However, AI differed from IN memory CD8 T cells by their capacity to migrate to the lung parenchyma upon inflammation or infection, a process dependent on their expression of ITGA1/CD49a and ITGA4/CD49d integrins. Copyright © 2018 by The American Association of Immunologists, Inc.

  16. Electrophysiological approach to determine kinetic parameters of sucrose uptake by single sieve elements or phloem parenchyma cells in intact Vicia faba plants.

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    Hafke, Jens B; Höll, Sabina-Roxana; Kühn, Christina; van Bel, Aart J E

    2013-01-01

    Apart from cut aphid stylets in combination with electrophysiology, no attempts have been made thus far to measure in vivo sucrose-uptake properties of sieve elements. We investigated the kinetics of sucrose uptake by single sieve elements and phloem parenchyma cells in Vicia faba plants. To this end, microelectrodes were inserted into free-lying phloem cells in the main vein of the youngest fully-expanded leaf, half-way along the stem, in the transition zone between the autotrophic and heterotrophic part of the stem, and in the root axis. A top-to-bottom membrane potential gradient of sieve elements was observed along the stem (-130 mV to -110 mV), while the membrane potential of the phloem parenchyma cells was stable (approx. -100 mV). In roots, the membrane potential of sieve elements dropped abruptly to -55 mV. Bathing solutions having various sucrose concentrations were administered and sucrose/H(+)-induced depolarizations were recorded. Data analysis by non-linear least-square data fittings as well as by linear Eadie-Hofstee (EH) -transformations pointed at biphasic Michaelis-Menten kinetics (2 MM, EH: K m1 1.2-1.8 mM, K m2 6.6-9.0 mM) of sucrose uptake by sieve elements. However, Akaike's Information Criterion (AIC) favored single MM kinetics. Using single MM as the best-fitting model, K m values for sucrose uptake by sieve elements decreased along the plant axis from 1 to 7 mM. For phloem parenchyma cells, higher K m values (EH: K m1 10 mM, K m2 70 mM) as compared to sieve elements were found. In preliminary patch-clamp experiments with sieve-element protoplasts, small sucrose-coupled proton currents (-0.1 to -0.3 pA/pF) were detected in the whole-cell mode. In conclusion (a) K m values for sucrose uptake measured by electrophysiology are similar to those obtained with heterologous systems, (b) electrophysiology provides a useful tool for in situ determination of K m values, (c) As yet, it remains unclear if one or two uptake systems are involved in sucrose

  17. Long-distance transport of mRNA via parenchyma cells and phloem across the host-parasite junction in Cuscuta.

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    David-Schwartz, Rakefet; Runo, Steven; Townsley, Brad; Machuka, Jesse; Sinha, Neelima

    2008-01-01

    It has been shown that the parasitic plant dodder (Cuscuta pentagona) establishes a continuous vascular system through which water and nutrients are drawn. Along with solutes, viruses and proteins, mRNA transcripts are transported from the host to the parasite. The path of the transcripts and their stability in the parasite have yet to be revealed. To discover the route of mRNA transportation, the in situ reverse transcriptase-polymerase chain reaction (RT-PCR) technique was used to locally amplify host transcript within parasitic tissue. The stability of host mRNA molecules was also checked by monitoring specific transcripts along the growing dodder thread. Four mRNAs, alpha and beta subunits of PYROPHOSPHATE (PPi)-DEPENDENT PHOSPHOFRUCTOKINASE (LePFP), the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), and GIBBERELLIC ACID INSENSITIVE (LeGAI), were found to move from host (tomato (Solanum lycopersicum)) to dodder. LePFP mRNA was localized to the dodder parenchyma cells and to the phloem. LePFP transcripts were found in the growing dodder stem up to 30 cm from the tomato-dodder connection. These results suggest that mRNA molecules are transferred from host to parasite via symplastic connections between parenchyma cells, move towards the phloem, and are stable for a long distance in the parasite. This may allow developmental coordination between the parasite and its host.

  18. Trypanosoma brucei Invasion and T-Cell Infiltration of the Brain Parenchyma in Experimental Sleeping Sickness: Timing and Correlation with Functional Changes.

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    Claudia Laperchia

    2016-12-01

    Full Text Available The timing of Trypanosoma brucei entry into the brain parenchyma to initiate the second, meningoencephalitic stage of human African trypanosomiasis or sleeping sickness is currently debated and even parasite invasion of the neuropil has been recently questioned. Furthermore, the relationship between neurological features and disease stage are unclear, despite the important diagnostic and therapeutic implications.Using a rat model of chronic Trypanosoma brucei brucei infection we determined the timing of parasite and T-cell neuropil infiltration and its correlation with functional changes. Parasite DNA was detected using trypanosome-specific PCR. Body weight and sleep structure alterations represented by sleep-onset rapid eye movement (SOREM periods, reported in human and experimental African trypanosomiasis, were monitored. The presence of parasites, as well as CD4+ and CD8+ T-cells in the neuropil was assessed over time in the brain of the same animals by immunocytochemistry and quantitative analyses.Trypanosome DNA was present in the brain at day 6 post-infection and increased more than 15-fold by day 21. Parasites and T-cells were observed in the parenchyma from day 9 onwards. Parasites traversing blood vessel walls were observed in the hypothalamus and other brain regions. Body weight gain was reduced from day 7 onwards. SOREM episodes started in most cases early after infection, with an increase in number and duration after parasite neuroinvasion.These findings demonstrate invasion of the neuropil over time, after an initial interval, by parasites and lymphocytes crossing the blood-brain barrier, and show that neurological features can precede this event. The data thus challenge the current clinical and cerebrospinal fluid criteria of disease staging.

  19. Trypanosoma brucei Invasion and T-Cell Infiltration of the Brain Parenchyma in Experimental Sleeping Sickness: Timing and Correlation with Functional Changes.

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    Laperchia, Claudia; Palomba, Maria; Seke Etet, Paul F; Rodgers, Jean; Bradley, Barbara; Montague, Paul; Grassi-Zucconi, Gigliola; Kennedy, Peter G E; Bentivoglio, Marina

    2016-12-01

    The timing of Trypanosoma brucei entry into the brain parenchyma to initiate the second, meningoencephalitic stage of human African trypanosomiasis or sleeping sickness is currently debated and even parasite invasion of the neuropil has been recently questioned. Furthermore, the relationship between neurological features and disease stage are unclear, despite the important diagnostic and therapeutic implications. Using a rat model of chronic Trypanosoma brucei brucei infection we determined the timing of parasite and T-cell neuropil infiltration and its correlation with functional changes. Parasite DNA was detected using trypanosome-specific PCR. Body weight and sleep structure alterations represented by sleep-onset rapid eye movement (SOREM) periods, reported in human and experimental African trypanosomiasis, were monitored. The presence of parasites, as well as CD4+ and CD8+ T-cells in the neuropil was assessed over time in the brain of the same animals by immunocytochemistry and quantitative analyses. Trypanosome DNA was present in the brain at day 6 post-infection and increased more than 15-fold by day 21. Parasites and T-cells were observed in the parenchyma from day 9 onwards. Parasites traversing blood vessel walls were observed in the hypothalamus and other brain regions. Body weight gain was reduced from day 7 onwards. SOREM episodes started in most cases early after infection, with an increase in number and duration after parasite neuroinvasion. These findings demonstrate invasion of the neuropil over time, after an initial interval, by parasites and lymphocytes crossing the blood-brain barrier, and show that neurological features can precede this event. The data thus challenge the current clinical and cerebrospinal fluid criteria of disease staging.

  20. EGFRvIII-specific chimeric antigen receptor T cells migrate to and kill tumor deposits infiltrating the brain parenchyma in an invasive xenograft model of glioblastoma.

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    Miao, Hongsheng; Choi, Bryan D; Suryadevara, Carter M; Sanchez-Perez, Luis; Yang, Shicheng; De Leon, Gabriel; Sayour, Elias J; McLendon, Roger; Herndon, James E; Healy, Patrick; Archer, Gary E; Bigner, Darell D; Johnson, Laura A; Sampson, John H

    2014-01-01

    Glioblastoma (GBM) is the most common primary malignant brain tumor in adults and is uniformly lethal. T-cell-based immunotherapy offers a promising platform for treatment given its potential to specifically target tumor tissue while sparing the normal brain. However, the diffuse and infiltrative nature of these tumors in the brain parenchyma may pose an exceptional hurdle to successful immunotherapy in patients. Areas of invasive tumor are thought to reside behind an intact blood brain barrier, isolating them from effective immunosurveillance and thereby predisposing the development of "immunologically silent" tumor peninsulas. Therefore, it remains unclear if adoptively transferred T cells can migrate to and mediate regression in areas of invasive GBM. One barrier has been the lack of a preclinical mouse model that accurately recapitulates the growth patterns of human GBM in vivo. Here, we demonstrate that D-270 MG xenografts exhibit the classical features of GBM and produce the diffuse and invasive tumors seen in patients. Using this model, we designed experiments to assess whether T cells expressing third-generation chimeric antigen receptors (CARs) targeting the tumor-specific mutation of the epidermal growth factor receptor, EGFRvIII, would localize to and treat invasive intracerebral GBM. EGFRvIII-targeted CAR (EGFRvIII+ CAR) T cells demonstrated in vitro EGFRvIII antigen-specific recognition and reactivity to the D-270 MG cell line, which naturally expresses EGFRvIII. Moreover, when administered systemically, EGFRvIII+ CAR T cells localized to areas of invasive tumor, suppressed tumor growth, and enhanced survival of mice with established intracranial D-270 MG tumors. Together, these data demonstrate that systemically administered T cells are capable of migrating to the invasive edges of GBM to mediate antitumor efficacy and tumor regression.

  1. EGFRvIII-specific chimeric antigen receptor T cells migrate to and kill tumor deposits infiltrating the brain parenchyma in an invasive xenograft model of glioblastoma.

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    Hongsheng Miao

    Full Text Available Glioblastoma (GBM is the most common primary malignant brain tumor in adults and is uniformly lethal. T-cell-based immunotherapy offers a promising platform for treatment given its potential to specifically target tumor tissue while sparing the normal brain. However, the diffuse and infiltrative nature of these tumors in the brain parenchyma may pose an exceptional hurdle to successful immunotherapy in patients. Areas of invasive tumor are thought to reside behind an intact blood brain barrier, isolating them from effective immunosurveillance and thereby predisposing the development of "immunologically silent" tumor peninsulas. Therefore, it remains unclear if adoptively transferred T cells can migrate to and mediate regression in areas of invasive GBM. One barrier has been the lack of a preclinical mouse model that accurately recapitulates the growth patterns of human GBM in vivo. Here, we demonstrate that D-270 MG xenografts exhibit the classical features of GBM and produce the diffuse and invasive tumors seen in patients. Using this model, we designed experiments to assess whether T cells expressing third-generation chimeric antigen receptors (CARs targeting the tumor-specific mutation of the epidermal growth factor receptor, EGFRvIII, would localize to and treat invasive intracerebral GBM. EGFRvIII-targeted CAR (EGFRvIII+ CAR T cells demonstrated in vitro EGFRvIII antigen-specific recognition and reactivity to the D-270 MG cell line, which naturally expresses EGFRvIII. Moreover, when administered systemically, EGFRvIII+ CAR T cells localized to areas of invasive tumor, suppressed tumor growth, and enhanced survival of mice with established intracranial D-270 MG tumors. Together, these data demonstrate that systemically administered T cells are capable of migrating to the invasive edges of GBM to mediate antitumor efficacy and tumor regression.

  2. Plasma Cell Type of Castleman's Disease Involving Renal Parenchyma and Sinus with Cardiac Tamponade: Case Report and Literature Review

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    Kim, Tae Un; Kim, Suk; Lee, Jun Woo; Lee, Nam Kyung; Jeon, Ung Bae; Ha, Hong Gu; Shin, Dong Hoon [Pusan National University Yangsan Hospital, Pusan National University School of Medicine, Yangsan (Korea, Republic of)

    2012-09-15

    Castleman's disease is an uncommon disorder characterized by benign proliferation of the lymphoid tissue that occurs most commonly in the mediastinum. Although unusual locations and manifestations have been reported, involvement of the renal parenchyma and sinus, and moreover, manifestations as cardiac tamponade are extremely rare. Here, we present a rare case of Castleman's disease in the renal parenchyma and sinus that also accompanied cardiac tamponade.

  3. Wood anatomical correlates with theoretical conductivity and wood density across China: evolutionary evidence of the functional differentiation of axial and radial parenchyma.

    Science.gov (United States)

    Zheng, Jingming; Martínez-Cabrera, Hugo I

    2013-09-01

    In recent years considerable effort has focused on linking wood anatomy and key ecological traits. Studies analysing large databases have described how these ecological traits vary as a function of wood anatomical traits related to conduction and support, but have not considered how these functions interact with cells involved in storage of water and carbohydrates (i.e. parenchyma cells). We analyzed, in a phylogenetic context, the functional relationship between cell types performing each of the three xylem functions (conduction, support and storage) and wood density and theoretical conductivity using a sample of approx. 800 tree species from China. Axial parenchyma and rays had distinct evolutionary correlation patterns. An evolutionary link was found between high conduction capacity and larger amounts of axial parenchyma that is probably related to water storage capacity and embolism repair, while larger amounts of ray tissue have evolved with increased mechanical support and reduced hydraulic capacity. In a phylogenetic principal component analysis this association of axial parenchyma with increased conduction capacity and rays with wood density represented orthogonal axes of variation. In multivariate space, however, the proportion of rays might be positively associated with conductance and negatively with wood density, indicating flexibility in these axes in species with wide rays. The findings suggest that parenchyma types may differ in function. The functional axes represented by different cell types were conserved across lineages, suggesting a significant role in the ecological strategies of the angiosperms.

  4. Transcript Profiling Identifies NAC-Domain Genes Involved in Regulating Wall Ingrowth Deposition in Phloem Parenchyma Transfer Cells of Arabidopsis thaliana

    Directory of Open Access Journals (Sweden)

    Yuzhou Wu

    2018-03-01

    Full Text Available Transfer cells (TCs play important roles in facilitating enhanced rates of nutrient transport at key apoplasmic/symplasmic junctions along the nutrient acquisition and transport pathways in plants. TCs achieve this capacity by developing elaborate wall ingrowth networks which serve to increase plasma membrane surface area thus increasing the cell's surface area-to-volume ratio to achieve increased flux of nutrients across the plasma membrane. Phloem parenchyma (PP cells of Arabidopsis leaf veins trans-differentiate to become PP TCs which likely function in a two-step phloem loading mechanism by facilitating unloading of photoassimilates into the apoplasm for subsequent energy-dependent uptake into the sieve element/companion cell (SE/CC complex. We are using PP TCs in Arabidopsis as a genetic model to identify transcription factors involved in coordinating deposition of the wall ingrowth network. Confocal imaging of pseudo-Schiff propidium iodide-stained tissue revealed different profiles of temporal development of wall ingrowth deposition across maturing cotyledons and juvenile leaves, and a basipetal gradient of deposition across mature adult leaves. RNA-Seq analysis was undertaken to identify differentially expressed genes common to these three different profiles of wall ingrowth deposition. This analysis identified 68 transcription factors up-regulated two-fold or more in at least two of the three experimental comparisons, with six of these transcription factors belonging to Clade III of the NAC-domain family. Phenotypic analysis of these NAC genes using insertional mutants revealed significant reductions in levels of wall ingrowth deposition, particularly in a double mutant of NAC056 and NAC018, as well as compromised sucrose-dependent root growth, indicating impaired capacity for phloem loading. Collectively, these results support the proposition that Clade III members of the NAC-domain family in Arabidopsis play important roles in

  5. Imaging manifestations of the cavitation in pulmonary parenchyma of SARS

    International Nuclear Information System (INIS)

    Yuan Chunwang; Zhao Dawei; Wang Wei; Jia Cuiyu; Bai Chunsheng

    2004-01-01

    Objective: To investigate the imaging appearances of cavitation in pulmonary parenchyma and the clinical features of the cases of SARS. Methods: Chest imaging films and clinical data of 180 patients with clinically confirmed SARS were analyzed retrospectively. The imaging manifestations of cavitation and the clinical features of the patients were observed and evaluated. Results: Of 180 patients, cavitations were showed in 5 (2.8%), which were all found through X-ray or CT scanning. Most of them were round or irregular, and had thick wall. The 5 patients all had been in hospital and treated with more dosage antibiotics, antivirus medicines and glucocorticoid for long time, the glucocorticoid was used for 25-65 d, and in the first 10-15 days the dosage was 160-240 mg per day. In hospitalization, one of them had been diagnosed diabetes mellitus, four had increased fasting blood sugar, the counts of white blood cells [(14.1-20.4) x 10 9 /L] increased significantly, the percent of neutrophils might increased also. Meanwhile, there was a continue increase of lactate dehydrogenase (228.00-475.00 U/L), glutamic dehydrogenase (10.08-60.00 U/L) and hydroxybutyrate dehydrogenase (190.00-444.00 U/L) in lab examination. Conclusion: SARS can cause cavitation in pulmonary parenchyma in posterior process of the disease. CT scanning can find the cavitation earlier and accurately, catching the imaging features of them is helpful in differential diagnosis, guiding therapy and estimating prognosis

  6. Micromechanical model of lung parenchyma hyperelasticity

    Science.gov (United States)

    Concha, Felipe; Sarabia-Vallejos, Mauricio; Hurtado, Daniel E.

    2018-03-01

    Mechanics plays a key role in respiratory physiology, as lung tissue cyclically deforms to bring air in and out the lung, a life-long process necessary for respiration. The study of regional mechanisms of deformation in lung parenchyma has received great attention to date due to its clinical relevance, as local overstretching and stress concentration in lung tissue is currently associated to pathological conditions such as lung injury during mechanical ventilation therapy. This mechanical approach to lung physiology has motivated the development of constitutive models to better understand the relation between stress and deformation in the lung. While material models proposed to date have been key in the development of whole-lung simulations, either they do not directly relate microstructural properties of alveolar tissue with coarse-scale behavior, or they require a high computational effort when based on real alveolar geometries. Furthermore, most models proposed to date have not been thoroughly validated for anisotropic deformation states, which are commonly found in normal lungs in-vivo. In this work, we develop a novel micromechanical model of lung parenchyma hyperelasticity using the framework of finite-deformation homogenization. To this end, we consider a tetrakaidecahedron unit cell with incompressible Neo-Hookean structural elements that account for the alveolar wall tissue responsible for the elastic response, and derive expressions for its effective coarse-scale behavior that directly depend on the alveolar wall elasticity, reference porosity, and two other geometrical coefficients. To validate the proposed model, we simulate the non-linear elastic response of twelve representative volume elements (RVEs) of lung parenchyma with micrometric dimensions, whose geometry is obtained from micrometric computed-tomography reconstructions of murine lungs. We show that the proposed micromechanical model accurately captures the RVEs response not only for isotropic

  7. Improved pulmonary nodule classification utilizing quantitative lung parenchyma features.

    Science.gov (United States)

    Dilger, Samantha K N; Uthoff, Johanna; Judisch, Alexandra; Hammond, Emily; Mott, Sarah L; Smith, Brian J; Newell, John D; Hoffman, Eric A; Sieren, Jessica C

    2015-10-01

    Current computer-aided diagnosis (CAD) models for determining pulmonary nodule malignancy characterize nodule shape, density, and border in computed tomography (CT) data. Analyzing the lung parenchyma surrounding the nodule has been minimally explored. We hypothesize that improved nodule classification is achievable by including features quantified from the surrounding lung tissue. To explore this hypothesis, we have developed expanded quantitative CT feature extraction techniques, including volumetric Laws texture energy measures for the parenchyma and nodule, border descriptors using ray-casting and rubber-band straightening, histogram features characterizing densities, and global lung measurements. Using stepwise forward selection and leave-one-case-out cross-validation, a neural network was used for classification. When applied to 50 nodules (22 malignant and 28 benign) from high-resolution CT scans, 52 features (8 nodule, 39 parenchymal, and 5 global) were statistically significant. Nodule-only features yielded an area under the ROC curve of 0.918 (including nodule size) and 0.872 (excluding nodule size). Performance was improved through inclusion of parenchymal (0.938) and global features (0.932). These results show a trend toward increased performance when the parenchyma is included, coupled with the large number of significant parenchymal features that support our hypothesis: the pulmonary parenchyma is influenced differentially by malignant versus benign nodules, assisting CAD-based nodule characterizations.

  8. High-resolution confocal imaging of wall ingrowth deposition in plant transfer cells: Semi-quantitative analysis of phloem parenchyma transfer cell development in leaf minor veins of Arabidopsis.

    Science.gov (United States)

    Nguyen, Suong T T; McCurdy, David W

    2015-04-23

    Transfer cells (TCs) are trans-differentiated versions of existing cell types designed to facilitate enhanced membrane transport of nutrients at symplasmic/apoplasmic interfaces. This transport capacity is conferred by intricate wall ingrowths deposited secondarily on the inner face of the primary cell wall, hence promoting the potential trans-membrane flux of solutes and consequently assigning TCs as having key roles in plant growth and productivity. However, TCs are typically positioned deep within tissues and have been studied mostly by electron microscopy. Recent advances in fluorophore labelling of plant cell walls using a modified pseudo-Schiff-propidium iodide (mPS-PI) staining procedure in combination with high-resolution confocal microscopy have allowed visualization of cellular details of individual tissue layers in whole mounts, hence enabling study of tissue and cellular architecture without the need for tissue sectioning. Here we apply a simplified version of the mPS-PI procedure for confocal imaging of cellulose-enriched wall ingrowths in vascular TCs at the whole tissue level. The simplified mPS-PI staining procedure produced high-resolution three-dimensional images of individual cell types in vascular bundles and, importantly, wall ingrowths in phloem parenchyma (PP) TCs in minor veins of Arabidopsis leaves and companion cell TCs in pea. More efficient staining of tissues was obtained by replacing complex clearing procedures with a simple post-fixation bleaching step. We used this modified procedure to survey the presence of PP TCs in other tissues of Arabidopsis including cotyledons, cauline leaves and sepals. This high-resolution imaging enabled us to classify different stages of wall ingrowth development in Arabidopsis leaves, hence enabling semi-quantitative assessment of the extent of wall ingrowth deposition in PP TCs at the whole leaf level. Finally, we conducted a defoliation experiment as an example of using this approach to statistically

  9. Infiltration of peritumoural but tumour-free parenchyma with IgG4-positive plasma cells in hilar cholangiocarcinoma and pancreatic adenocarcinoma.

    Science.gov (United States)

    Resheq, Yazid J; Quaas, Alexander; von Renteln, Daniel; Schramm, Christoph; Lohse, Ansgar W; Lüth, Stefan

    2013-10-01

    Recently, new guidelines for diagnosing IgG4-associated cholangitis have been published devaluing the diagnostic significance of IgG4-positive plasma cells and steroid trials. We sought to evaluate the utility of IgG4-positive plasma cells in discriminating IgG4-associated cholangitis from hilar cholangiocarcinoma and autoimmune pancreatitis from pancreatic adenocarcinoma under conditions when malignancy is likely to be missed. Resection specimens obtained from patients with hilar cholangiocarcinoma, pancreatic adenocarcinoma or hepatocellular carcinoma were re-evaluated for IgG4-positivity. Histological analysis focussed on peritumoural but tumour-free sections. Perioperative biochemical and clinical data were reviewed. Nineteen patients with hilar cholangiocarcinoma and 29 patients with pancreatic adenocarcinoma were eligible for histological re-evaluation. Six of 19 (32%) patients with hilar cholangiocarcinoma and 5 of 29 (17%) patients with pancreatic adenocarcinoma were IgG4-positive (≥20 IgG4-positive plasma cells per high power field). Patients with IgG4-positive hilar cholangiocarcinoma showed significantly higher levels of serum total bilirubin (3.6mg/dl vs. 1.8mg/dl; Philar cholangiocarcinoma. IgG4-positive plasma cells are of limited utility especially in distinguishing hilar cholangiocarcinoma from IgG4-associated cholangitis even when combined with clinical parameters and may be misleading under conditions when malignancy is missed. Copyright © 2013 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  10. Cell survival studies using ultrasoft x rays

    International Nuclear Information System (INIS)

    Schillaci, M.E.; Raju, M.R.; Carpenter, S.; Cornforth, M.; Wilder, M.

    1987-01-01

    Cell survival was studied for V79 hamster, 10T1/2 mouse, and human skin fibroblast cell lines, using carbon K (0.28 keV), copper K (8.0 keV), and 250 kVp x rays. Because of the rapid attenuation of the carbon x rays, cellular dimensions at the time of exposure were measured using optical and electron microscopy, and frequency distributions of mean dose absorbed by the cell nucleus were obtained. The results indicate that the differences in cell killing between ultra-soft and hard x rays may depend on the nuclear thickness of the cells. Studies of the effects of hypoxia on V79 and 10T1/2 cells using carbon K, aluminum K (1.5 keV), and copper K x rays show decreasing OER values with decreasing x-ray energy and no difference between the two cell lines. Age response studies with V79 cells show similar cell-cycle variation of survival for carbon K and aluminum K x rays as for hard x rays

  11. Dissimilarity Representations in Lung Parenchyma Classification

    DEFF Research Database (Denmark)

    Sørensen, Lauge Emil Borch Laurs; de Bruijne, Marleen

    2009-01-01

    parenchyma classification. This allows for the classifiers to work on dissimilarities between objects, which might be a more natural way of representing lung parenchyma. In this context, dissimilarity is defined between CT regions of interest (ROI)s. ROIs are represented by their CT attenuation histogram...... and ROI dissimilarity is defined as a histogram dissimilarity measure between the attenuation histograms. In this setting, the full histograms are utilized according to the chosen histogram dissimilarity measure. We apply this idea to classification of different emphysema patterns as well as normal...... are built in this representation. This is also the general trend in lung parenchyma classification in computed tomography (CT) images, where the features often are measures on feature histograms. Instead, we propose to build normal density based classifiers in dissimilarity representations for lung...

  12. Early invasion of brain parenchyma by African trypanosomes.

    Directory of Open Access Journals (Sweden)

    Ute Frevert

    Full Text Available Human African trypanosomiasis or sleeping sickness is a vector-borne parasitic disease that has a major impact on human health and welfare in sub-Saharan countries. Based mostly on data from animal models, it is currently thought that trypanosome entry into the brain occurs by initial infection of the choroid plexus and the circumventricular organs followed days to weeks later by entry into the brain parenchyma. However, Trypanosoma brucei bloodstream forms rapidly cross human brain microvascular endothelial cells in vitro and appear to be able to enter the murine brain without inflicting cerebral injury. Using a murine model and intravital brain imaging, we show that bloodstream forms of T. b. brucei and T. b. rhodesiense enter the brain parenchyma within hours, before a significant level of microvascular inflammation is detectable. Extravascular bloodstream forms were viable as indicated by motility and cell division, and remained detectable for at least 3 days post infection suggesting the potential for parasite survival in the brain parenchyma. Vascular inflammation, as reflected by leukocyte recruitment and emigration from cortical microvessels, became apparent only with increasing parasitemia at later stages of the infection, but was not associated with neurological signs. Extravascular trypanosomes were predominantly associated with postcapillary venules suggesting that early brain infection occurs by parasite passage across the neuroimmunological blood brain barrier. Thus, trypanosomes can invade the murine brain parenchyma during the early stages of the disease before meningoencephalitis is fully established. Whether individual trypanosomes can act alone or require the interaction from a quorum of parasites remains to be shown. The significance of these findings for disease development is now testable.

  13. X-rays sensitive mammalian cell mutant

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1982-01-01

    A phenomenon that in x-ray-sensitive mammalian-cell mutants, cellular death due to x-ray radiation was not increased by caffeine, but on the contrary, the dead cells were resuscitated by it was discussed. The survival rate of mutant cells increased by caffein in a low concentration. This suggested that caffeine may have induced some mechanism to produce x-ray resistant mutant cells. Postirradiation treatment with caffeine increased considerably the survival rate of the mutant cells, and this suggested the existence of latent caffeine-sensitive potentially lethal damage repair system. This system, after a few hours, is thought to be substituted by caffeine-resistant repair system which is induced by caffeine, and this may be further substituted by x-ray-resistant repair system. The repair system was also induced by adenine. (Ueda, J.)

  14. X-ray irradiation of yeast cells

    Science.gov (United States)

    Masini, Alessandra; Batani, Dimitri; Previdi, Fabio; Conti, Aldo; Pisani, Francesca; Botto, Cesare; Bortolotto, Fulvia; Torsiello, Flavia; Turcu, I. C. Edmond; Allott, Ric M.; Lisi, Nicola; Milani, Marziale; Costato, Michele; Pozzi, Achille; Koenig, Michel

    1997-10-01

    Saccharomyces Cerevisiae yeast cells were irradiated using the soft X-ray laser-plasma source at Rutherford Laboratory. The aim was to produce a selective damage of enzyme metabolic activity at the wall and membrane level (responsible for fermentation) without interfering with respiration (taking place in mitochondria) and with nuclear and DNA activity. The source was calibrated by PIN diodes and X-ray spectrometers. Teflon stripes were chosen as targets for the UV laser, emitting X-rays at about 0.9 keV, characterized by a very large decay exponent in biological matter. X-ray doses to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. After irradiation, the selective damage to metabolic activity at the membrane level was measured by monitoring CO2 production with pressure silicon detectors. Preliminary results gave evidence of pressure reduction for irradiated samples and non-linear response to doses. Also metabolic oscillations were evidenced in cell suspensions and it was shown that X-ray irradiation changed the oscillation frequency.

  15. [ULTRASTRUCTURE OF PARENCHYMA IN THE SYNCYTIAL DIGESTIVE SYSTEM IN TURBELLARIA Convoluta convoluta (Acoela].

    Science.gov (United States)

    Gazizova, G R; Zabotin, Ya I; Golubev, A I

    2015-01-01

    The paper presents data on the ultrastructure of parenchyma that is involved in the digestion in turbellaria Convoluta convoluta (n = 15). Unusual connections between the nuclear envelope, endoplasmic reticulum and plasma membrane of parenchymal cells were found for the first time, which may indicate the origin of these cell structures. The double trophic role of zooxanthellae in the organism of Convoluta is described.

  16. Correlation between alveolar ventilation and electrical properties of lung parenchyma.

    Science.gov (United States)

    Roth, Christian J; Ehrl, Andreas; Becher, Tobias; Frerichs, Inéz; Schittny, Johannes C; Weiler, Norbert; Wall, Wolfgang A

    2015-06-01

    One key problem in modern medical imaging is linking measured data and actual physiological quantities. In this article we derive such a link between the electrical bioimpedance of lung parenchyma, which can be measured by electrical impedance tomography (EIT), and the magnitude of regional ventilation, a key to understanding lung mechanics and developing novel protective ventilation strategies. Two rat-derived three-dimensional alveolar microstructures obtained from synchrotron-based x-ray tomography are each exposed to a constant potential difference for different states of ventilation in a finite element simulation. While the alveolar wall volume remains constant during stretch, the enclosed air volume varies, similar to the lung volume during ventilation. The enclosed air, serving as insulator in the alveolar ensemble, determines the resulting current and accordingly local tissue bioimpedance. From this we can derive a relationship between lung tissue bioimpedance and regional alveolar ventilation. The derived relationship shows a linear dependence between air content and tissue impedance and matches clinical data determined from a ventilated patient at the bedside.

  17. Radiologic imaging of the renal parenchyma structure and function.

    Science.gov (United States)

    Grenier, Nicolas; Merville, Pierre; Combe, Christian

    2016-06-01

    Radiologic imaging has the potential to identify several functional and/or structural biomarkers of acute and chronic kidney diseases that are useful diagnostics to guide patient management. A renal ultrasound examination can provide information regarding the gross anatomy and macrostructure of the renal parenchyma, and ultrasound imaging modalities based on Doppler or elastography techniques can provide haemodynamic and structural information, respectively. CT is also able to combine morphological and functional information, but the use of CT is limited due to the required exposure to X-ray irradiation and a risk of contrast-induced nephropathy following intravenous injection of a radio-contrast agent. MRI can be used to identify a wide range of anatomical and physiological parameters at the tissue and even cellular level, such as tissue perfusion, oxygenation, water diffusion, cellular phagocytic activity, tissue stiffness, and level of renal filtration. The ability of MRI to provide valuable information for most of these parameters within a renal context is still in development and requires more clinical experience, harmonization of technical procedures, and an evaluation of reliability and validity on a large scale.

  18. Post-transplant Lymphoproliferative Disorder Arising from Renal Allograft Parenchyma: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Byung Kwan; Kim, Chan Kyo; Kwon, Ghee Young [Samsung Medical Center, Sungkyunkwan University College of Medicine, Seoul (Korea, Republic of)

    2010-06-15

    Post-transplant lymphoproliferative disorder (PTLD) is a rare but serious complication that occurs in patients undergoing kidney transplantation. PTLD usually manifests as a renal hilar mass comprised of histologically B-lymphocytes. We report our experience of managing a patient with PTLD arising from renal parenchyma. Ultrasonographic and MR imaging features of this unusual PTLD suggested differentiated renal cell carcinoma arising from the renal allograft

  19. Protease activation involved in resistance of human cells to x-ray cell killing

    International Nuclear Information System (INIS)

    Zhang, Hong-Chang; Takahashi, Shuji; Karata, Kiyonobu; Kita, Kazuko; Suzuki, Nobuo

    2003-01-01

    Little is known of proteases that play roles in the early steps of X-ray irradiation response. In the present study, we first searched for proteases whose activity is induced in human RSa-R cells after X-ray irradiation. The activity was identified as fibrinolytic, using 125 I-labeled fibrin as a substrate. Protease samples were prepared by lysation of cells with a buffer containing MEGA-8. RSa-R cells showed an increased level of protease activity 10 min after X-ray (up to 3 Gy) irradiation. We next examined whether this protease inducibility is causally related with the X-ray susceptibility of cells. Leupeptin, a serine-cysteine protease inhibitor, inhibited the protease activity in samples obtained from X-ray-irradiated RSa-R cells. Treatment of RSa-R cells with the inhibitor before and after X-ray irradiation resulted in an increased susceptibility of the cells to X-ray cell killing. However, the treatment of cells with other inhibitors tested did not modulate the X-ray susceptibility. These results suggest that leupeptin-sensitive proteases are involved in the resistance of human cells to X-ray cell killing. (author)

  20. X-ray microanalysis of single and cultured cells

    International Nuclear Information System (INIS)

    Wroblewski, J.; Roomans, G.M.

    1984-01-01

    X-ray microanalysis of single or cultured cells is often a useful alternative or complement to the analysis of the corresponding tissue. It also allows the analysis of individual cells in a cell population. Preparation for X-ray microanalysis poses a number of typical problems. Suspensions of single cells can be prepared by either of two pathways: (1) washing - mounting - drying, or (2) centrifugation - freezing or fixation - sectioning. The washing step in the preparation of single or cultured cells presents the most severe problems. Cultured cells are generally grown on a substrate that is compatible with both the analysis and the culture, washed and dried. In some cases, sectioning of cultured cell monolayers has been performed. Special problems in quantitative analysis occur in those cases where the cells are analyzed on a thick substrate, since the substrate contributes to the spectral background

  1. A single cell model for pretreatment of wood by microwave explosion

    Science.gov (United States)

    Xianjun Li; Yongdong Zhou; Yonglin Yan; Zhiyong Cai; Fu Feng

    2010-01-01

    A theoretical model was developed to better understand the process of microwave explosion treatment of wood cells. The cell expansion and critical conditions concerning pressure and temperature of ray parenchyma cells in Eucalyptus urophylla were simulated during microwave pretreatment. The results indicate that longitudinal and circumferential stresses were generated...

  2. The apoptosis of CHO cells induced by X-rays

    International Nuclear Information System (INIS)

    Lu Zhaohong; Zhao Jingyong; Zhu Mingqing; Shi Xijin; Wang Chunlei

    2004-01-01

    The work is to study the mechanism of toxic effects on reproductive system and apoptosis of Chinese hamster ovary (CHO) cells induced by X-rays. CHO cell was exposed to X-rays 2 to 20 Gy. Apoptosis and morphological changes of the cells were observed by fluorescent microscopy and flow cytometry analyzer with double staining with Annexin V/PI. The apoptosis could be observed at 24, 48 and 72h after the exposure, but it was more obvious 48 and 72 h after the exposure. Rate of the apoptosis increased along with radiation dose were elevated. Some morphological changes, such as irregular agglomerate of chromatins, pycnosis and periphery distribution of nuclei, crescent-moon-like cells, small apoptosis body, were observed. Radiation results DNA damage in the CHO cells, and the damage cannot be repaired, hence the induced cell apoptosis. (authors)

  3. Effects of soft x-ray irradiation on cell ultrastructure

    International Nuclear Information System (INIS)

    Ford, T.W.; Page, A.M.; Stead, A.D.; Foster, G.F.

    1993-01-01

    The future of X-ray microscopy lies mainly in its potential for imaging fresh, hydrated biological material at a resolution superior to that of light microscopy. For the image to be accepted as representing the cellular organization of the living cell, it is essential that artifacts are not introduced as a result of the image collection system. One possible source of artifacts is cellular damage resulting from the irradiation of the material with soft X-rays. Cells of the unicellular alga Chlorella have been examined by transmission electron microscopy (TEM) following exposure to different doses of monochromatic (380eV) soft X-rays. Extreme ultrastructural damage has been detected following doses of 10 3 -10 4 Gy, in particular loss of cellular membranes such as the internal thylakoid membranes of the chloroplast. This is discussed in relation to dosage commonly used for imaging by soft X-ray microscopy

  4. Characterization of the Lung Parenchyma Using Ultrasound Multiple Scattering.

    Science.gov (United States)

    Mohanty, Kaustav; Blackwell, John; Egan, Thomas; Muller, Marie

    2017-05-01

    The purpose of the study described here was to showcase the application of ultrasound to quantitative characterization of the micro-architecture of the lung parenchyma to predict the extent of pulmonary edema. The lung parenchyma is a highly complex and diffusive medium for which ultrasound techniques have remained qualitative. The approach presented here is based on ultrasound multiple scattering and exploits the complexity of ultrasound propagation in the lung structure. The experimental setup consisted of a linear transducer array with an 8-MHz central frequency placed in contact with the lung surface. The diffusion constant D and transport mean free path L* of the lung parenchyma were estimated by separating the incoherent and coherent intensities in the near field and measuring the growth of the incoherent diffusive halo over time. Significant differences were observed between the L* values obtained in healthy and edematous rat lungs in vivo. In the control rat lung, L* was found to be 332 μm (±48.8 μm), whereas in the edematous lung, it was 1040 μm (±90 μm). The reproducibility of the measurements of L* and D was tested in vivo and in phantoms made of melamine sponge with varying air volume fractions. Two-dimensional finite difference time domain numerical simulations were carried out on rabbit lung histology images with varying degrees of lung collapse. Significant correlations were observed between air volume fraction and L* in simulation (r = -0.9542, p lung in which edema was simulated by adding phosphate-buffered saline revealed a linear relationship between the fluid volume fraction and L*. These results illustrate the potential of methods based on ultrasound multiple scattering for the quantitative characterization of the lung parenchyma. Copyright © 2017 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

  5. Correlation between alveolar ventilation and electrical properties of lung parenchyma

    OpenAIRE

    Roth, J. C., Ehrl, A., Becher, T., Frerichs, I., Schittny, J., Weller, N., Wall W. A.

    2016-01-01

    One key problem in modern medical imaging is linking measured data and actual physiological quantities. In this article we derive such a link between the electrical bioimpedance of lung parenchyma, which can be measured by electrical impedance tomography (EIT), and the magnitude of regional ventilation, a key towards understanding lung mechanics and developing novel protective ventilation strategies. Two rat-derived three-dimensional alveolar microstructures obtained from synchrotron-ba...

  6. Polymorphonuclear neutrophil in brain parenchyma after experimental intracerebral hemorrhage.

    Science.gov (United States)

    Zhao, Xiurong; Sun, Guanghua; Zhang, Han; Ting, Shun-Ming; Song, Shen; Gonzales, Nicole; Aronowski, Jaroslaw

    2014-10-01

    Polymorphonuclear neutrophils (PMNs) infiltration into brain parenchyma after cerebrovascular accidents is viewed as a key component of secondary brain injury. Interestingly, a recent study of ischemic stroke suggests that after ischemic stroke, PMNs do not enter brain parenchyma and as such may cause no harm to the brain. Thus, the present study was designed to determine PMNs' behavior after intracerebral hemorrhage (ICH). Using the autologous blood injection model of ICH in rats and immunohistochemistry for PMNs and vascular components, we evaluated the temporal and spatial PMNs distribution in the ICH-affected brain. We found that, similar to ischemia, there is a robust increase in presence of PMNs in the ICH-injured tissue that lasts for at least 1 to 2 weeks. However, in contrast to what was suggested for ischemia, besides PMNs that stay in association with the vasculature, after ICH, we found abundance of intraparenchymal PMNs (with no obvious association with vessels) in the ICH core and hematoma border, especially between 1 and 7 days after the ictus. Interestingly, the increased presence of intraparenchymal PMNs after ICH coincided with the massive loss of microvascular integrity, suggesting vascular disruption as a potential cause of PMNs presence in the brain parenchyma. Our study indicates that in contrast to ischemic stroke, after ICH, PMNs target not only vascular compartment but also brain parenchyma in the affected brain. As such, it is possible that the pathogenic role and therapeutic implications of targeting PMNs after ICH could be different from these after ischemic stroke. Our work suggests the needs for more studies addressing the role of PMNs in ICH.

  7. A tree-parenchyma coupled model for lung ventilation simulation.

    Science.gov (United States)

    Pozin, Nicolas; Montesantos, Spyridon; Katz, Ira; Pichelin, Marine; Vignon-Clementel, Irene; Grandmont, Céline

    2017-11-01

    In this article, we develop a lung ventilation model. The parenchyma is described as an elastic homogenized media. It is irrigated by a space-filling dyadic resistive pipe network, which represents the tracheobronchial tree. In this model, the tree and the parenchyma are strongly coupled. The tree induces an extra viscous term in the system constitutive relation, which leads, in the finite element framework, to a full matrix. We consider an efficient algorithm that takes advantage of the tree structure to enable a fast matrix-vector product computation. This framework can be used to model both free and mechanically induced respiration, in health and disease. Patient-specific lung geometries acquired from computed tomography scans are considered. Realistic Dirichlet boundary conditions can be deduced from surface registration on computed tomography images. The model is compared to a more classical exit compartment approach. Results illustrate the coupling between the tree and the parenchyma, at global and regional levels, and how conditions for the purely 0D model can be inferred. Different types of boundary conditions are tested, including a nonlinear Robin model of the surrounding lung structures. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Effect of gamma irradiated parenchyma on the growth of irradiated potato tuber buds

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Garcia Collantes, M. A.

    1976-01-01

    The development of buds greffed on irradiated potato parenchyma was studied. The irradiated parenchyma does not influence the sprouting capacity of buds, but it affects the way they develop. (Author) 9 refs

  9. X-ray sensitivity of somatic cell hybrids

    International Nuclear Information System (INIS)

    Zampetti-Bosseler, F.; Heilporn, V.; Lievens, A.; Limbosch, S.

    1976-01-01

    Different somatic cell hybrids have been studied as a function of their x-ray survival and karyotypic properties. Hybrids between x-ray-sensitive mouse lymphoma cells and mouse fibroblasts, retaining a large proportion of both parental chromosomes, were much more resistant to irradiation than either of the parental cells. On the other hand, hybrids between sensitive mouse lymphoma cells and hamster fibroblasts which also retained a relatively high number of chromosomes from both parents had a sensitivity intermediate between the sensitivities of the parental cell lines. Finally, hybrids between mouse fibroblasts and hamster fibroblasts carrying at least one hamster genome and less than one mouse genome resembled the hamster parent with respect to survival capactity. The significance of these results is discussed

  10. A study on gamma rays from electrochemical cells

    International Nuclear Information System (INIS)

    Shin, Seung Ai

    1993-01-01

    The energies and intensities of gamma rays emitted from 3 cells with Pd-cathodes of φ 1mm x 10mm, φ 2mm x 20mm, φ 1mm x 10mm were determined using HPGe-detector system and compared with Pd-neutron capture model. Very strong gamma rays of 512keC, 622keC, 1051keC and 8 more important ones were found to be identical with characteristic gamma rays of 106 Pd and 109 Pd. It is likely that the neutron capture reaction, A PD(n, γ) A+1 Pd, occurred in the cell and the neutrons came from the fusion reaction of two deutrons. It is necessary, however, to retest the model since another strong 84keV-gamma rays do not belong to any A+1 Pd-gamma spectra and two important 106 Pd-gamma rays 717keV, 1046KeV were not detected. Total amount of emitted gamma rays was large when the size of the Pd-cathod was large. Its depedence on the time of measurement and the preheating period did not have any regularities. Thus the replication is not an easy thing. (Author)

  11. X-ray sensitivity of human tumor cells in vitro

    International Nuclear Information System (INIS)

    Weichselbaum, R.R.; Nove, J.; Little, J.B.

    1980-01-01

    Clonally-derived cells from ten human malignant tumors considered radiocurable (breast, neuroblastoma, medulloblastoma) or non-radiocurable (osteosarcoma, hypernephroma, glioblastoma, melanoma) were studied in cell culture and their in vitro x-ray survival curve parameters determined (anti n, D 0 ). There were no significant differences among the tumor cell lines suggesting that survival parameters in vitro do not explain differences in clinical radiocurability. Preliminary investigation with density inhibited human tumor cells indicate that such an approach may yield information regarding inherent cellular differences in radiocurability

  12. An X-ray absorption spectroelectrochemical cell for radioactive solutions

    International Nuclear Information System (INIS)

    Rettig, D.; Herrmann, S.; Mitschke, F.; Vonau, W.; Brendler, V.; Geipel, G.; Reich, T.; Bernhard, G.

    2002-01-01

    A spectroelectrochemical cell was designed and constructed for measurement of X-ray absorption spectra under electrochemical control of the redox potential of actinide-containing solutions. A first inactive test demonstrated the feasibility of an Ag anode as a non-gassing auxiliary electrode in chloride solutions. (orig.)

  13. Marrow fat cell: response to x-ray induced aplasia

    International Nuclear Information System (INIS)

    Bathija, A.; Ohanian, M.; Davis, S.; Trubowitz, S.

    1979-01-01

    Adipose tissue is an integral structural component of normal rabbit marrow and is believed to behave primarily as a cushion in response to hemopoietic proliferation, accommodating to changes in hemopoiesis by change in either size or number or both of the fat cells in order to maintain constancy of the marrow volume. To test this hypothesis, aplasia of the right femur of New Zealand white rabbits was induced by x irradiation with 8000 rads; the left unirradiated limb served as control. Twenty-four hours before sacrifice 50 μCi of palmitate-114C was administered intravenously and the marrow of both femurs removed. Samples of perinephric fat were taken for comparison. Fat cell volume, C14 palmitate turnover and fatty acid composition were determined. The total number of fat cells in the entire marrow of both femurs was calculated. The measurements showed no difference in size or fatty acid turnover of the fat cells in the irradiated aplastic marrow from the cells of the control marrow. The number of fat cells in both the irradiated and the unirradiated control femurs was essentially the same. These findings do not support the view that marrow fat cells respond to diminished hematopoiesis by either increase in their volume or number. In addition, the findings suggest that both marrow and subcutaneous fat cells are fairly resistant to high doses of x-ray irradiation

  14. X-ray repair replication in L1210 leukemia cells

    International Nuclear Information System (INIS)

    Lee, Y.C.; Byfield, J.E.; Bennett, L.R.; Chan, P.Y.M.

    1974-01-01

    Repair replication has been studied in detail in mouse L1210 leukemia cells. A method of identifying and quantitating repair replication using a pre- and postradiation block of normal replication with cytosine arabinoside is illustrated. The method derived does not require isolation of DNA per se and appears to be satisfactory for screening for inhibitors of repair replication. Repair replication can be demonstrated at doses in the 1000-rad range in bromouridine deoxyriboside-substituted cells and at slightly higher doses in nonsubstituted cells. Drugs that are known to bind to DNA inhibit this x-ray-induced repair replication. Drugs with these properties may be identified by the methods described and compared quantitatively in their ability to inhibit this type of x-ray damage. Since these phenomena can be demonstrated for low radiation doses and at drug concentrations attainable in vivo during human cancer chemotherapy this class of anticancer agent may be worthy of closer study. Application to the L1210 leukemia system should permit comparison of in vitro and in vivo drug effects in the context of the extensive in vivo pharmacological data already available for L1210 cells. (U.S.)

  15. X-ray and radioiodine dose to thyroid follicular cells

    International Nuclear Information System (INIS)

    Faw, R.E.

    1991-01-01

    Radiation doses to the epithelial cells of thyroid follicles have been calculated for internal exposure by radionuclides of iodine and by secondary radiations created as a result of interactions of externally administered x rays with iodine naturally occurring in the thyroid. Calculations were performed for the thyroids of subjects ranging from the newborn to the adult male. Results for internal radionuclides are reported as the dose rate to follicular-cell nuclei per unit specific activity of the radionuclide in the thyroid as a whole, i.e., as the specific ''S value'' as used in the MIRD method for internal dosimetry. Results for x rays are reported as the response function, i.e., the absorbed dose per unit fluence of primary x rays. Dose rates are subdivided into internal and external components, the former from radiations emitted within the colloid volume of any one follicle, and the latter from radiations emitted throughout the thyroid in follicles surrounding that one follicle. 37 refs., 5 figs., 3 tabs

  16. Implementation of a cabin X-rays in hot cell

    International Nuclear Information System (INIS)

    Berduola, F.; Caral, L.

    2001-01-01

    The Fabrice process for the reconstituted short length irradiated rods in a hot cell was developed by the CEA especially for power ramp testing. This technique requires intricate operations in a hot cell with specially adapted equipment and great skill people. And end plug is inserted under pressure and fitted to the opening end of a cladding tube. The meeting surfaces of the en plug and the opening end are welded by a TIG (tunsten inert gas) process. Nevertheless, somo predominate defects may occur in the end plug weld joints, such as lack of penetration and cavity. So, particular attention must be paid to non-destructive examination in particular X-ray control of welding areas. A radioscopy technique has been applied to the control of TIG welds of the end plugs to rod assemblies in a hot cell mock-up to be tested under realistic geometric conditions. This X-rays method enables immediate monitoring of any welding defaults on a TV screen. A remote positioning system for the Fabrice rod is being developed to position fuel rods below a X-ray source. Radioscopy pictures will be recorded during remote positioning of the rod movement. This document presents the modifications achieved by the constructor in cooperation with our laboratory staff, concerning the nuclearization of the apparatus as well as its implementation in the shielded hot cell n paragraph 2 of the CEA-DEC/SLS/LECA Laboratory in Cadarache. Hot operation of the rod positioner is planned for september 2022 because of recent refurbishing works in the plant. (Author)

  17. Physiological and biochemical aspects of the effect of ionizing radiations on the lung parenchyma

    International Nuclear Information System (INIS)

    Pasquier, Christian.

    1975-03-01

    Concerning the biochemical reactions of the lung parenchyma to irradiation the following points have been developed. Role of biochemically active substances (histamine, serotonin, kinins, catecholamines, prostaglandins) in the early reaction of the lung to irradiation, their common feature being their vascular impact point. Lung irradiation and lipids (fatty acids and lipid metabolism in general); irradiation, by raising the proportion of unsaturated at the expense of saturated fatty acids, may give rise to serious physiological respiratory disorders. Lung irradiation and blood fluidity (fibrinolytic activity, heparin, platelet factors). Pulmonary interstitium and irradiation (of the three interstitium components collagen plays a preferential part). Irradiation and immunological lung reaction (reasons behind the immunological theory, immunological assistance, immunological mechanism of pulmonary reactions towards pollutants). Enzymatic lung radiolesion indicators. Three kinds of physiological changes have been considered. Vascular physiology disturbances caused by the initial biochemical reactions; anomalies of physiological or functional trials, images of the lesion formed; disorders of the cell physiology of carcinogenesis [fr

  18. The structural and functional state of hemomicrocirculatory bed and parenchyma of the testis in varicocele

    Directory of Open Access Journals (Sweden)

    O. E. Khallo

    2015-08-01

    Full Text Available Varicose veins of the spermatic cord and testis membranes play a key role in the development of male infertility. Aim. To study the structural features of the bloodstream and testicular parenchyma in terms of varicose veins of the spermatic cord and testis membranes. Meyhods and results. In 23 testicular preparations taken from men of mature age convoluted seminiferous tubules diameter, number of cells of spermatogenic epithelium and interstitial endocrinocytes nuclei volume were studied using macro- and microscopic morphometric methods. It was established that in varicocele testis volume, diameter of convoluted seminiferous tubules and interstitial endocrinocytes nuclei volume significantly reduced. Conclusion. This indicates the presence of circulatory hypoxia of testicles, which leads to a decrease in the volume of interstitial endocrinocytes nuclei by 31%, thereby reducing their functional properties.

  19. Design of a tritium gas cell for beta-ray induced X-ray spectrometry using Monte Carlo simulation

    Energy Technology Data Exchange (ETDEWEB)

    Hara, Masanori, E-mail: masahara@ctg.u-toyama.ac.jp [Hydrogen Isotope Research Center, Organization for Promotion of Research, University of Toyama, 3190 Gofuku, Toyama City, Toyama 930-8555 (Japan); Abe, Shinsuke; Matsuyama, Masao [Hydrogen Isotope Research Center, Organization for Promotion of Research, University of Toyama, 3190 Gofuku, Toyama City, Toyama 930-8555 (Japan); Aso, Tsukasa [Electronics and Computer Engineering, National Institute of Technology, Toyama College, 1-2 Ebie-neriya, Imizu City, Toyama 933-0293 (Japan); Tatenuma, Katsuyoshi; Kawakami, Tomohiko; Ito, Takeshi [KAKEN Company Limited, 1044 Horimachi, Mito City, Ibaraki 310-0903 (Japan)

    2017-06-15

    Highlights: • Beta-ray induced X-ray spectrometry (BIXS) is a method for tritium gas analysis. • Gas cell for BIXS was designed by Monte Carlo simulations. • The optimum thickness of the gold layer on a beryllium window was around 150 nm. • This simulation model considered the self-absorption with increasing the cell length. - Abstract: One of the methods used for tritium gas analysis is beta-ray induced X-ray spectrometry (BIXS). Gas cell design is important in this method. The structure of the gas cell for BIXS was optimized by Monte Carlo simulation of beta-ray induced X-ray spectra in various window geometries using the Geant4 tool kit (version 10.01.p02). The simulated spectrum from tritium decay fitted the observed one, and the simulation model was used to obtain the cell parameters for BIXS. The optimum thickness of the gold layer on a beryllium window was around 150 nm. This simulation model also considered the relationship between self-absorption by hydrogen gas and the cell length. Self-absorption increased with increasing cell length and the relationship between the sample pressure and cell length was formulated.

  20. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, A. P., E-mail: aph@mcmaster.ca; Lee, V.; Wu, J.; Cooper, G. [Chemistry & Chemical Biology, McMaster University, Hamilton, ON, L8S 4M1 (Canada); West, M. M.; Berejnov, V. [Faculty of Health Sciences Electron Microscopy, McMaster University, Hamilton, ON L8N 3Z5 (Canada); Soboleva, T.; Susac, D.; Stumper, J. [Automotive Fuel Cell Cooperation Corp., Burnaby BC V5J 5J8 (Canada)

    2016-01-28

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined.

  1. Characterizing automotive fuel cell materials by soft x-ray scanning transmission x-ray microscopy

    International Nuclear Information System (INIS)

    Hitchcock, A. P.; Lee, V.; Wu, J.; Cooper, G.; West, M. M.; Berejnov, V.; Soboleva, T.; Susac, D.; Stumper, J.

    2016-01-01

    Proton-Exchange Membrane Fuel Cell (PEM-FC) based engines are being developed rapidly for near-term implementation in hydrogen fueled, mass production, personal automobiles. Research is focused on understanding and controlling various degradation processes (carbon corrosion, Pt migration, cold start), and reducing cost by reducing or eliminating Pt catalyst. We are using soft X-ray scanning transmission X-ray microscopy (STXM) at the S 2p, C 1s, O 1s and F 1s edges to study a variety of issues related to optimization of PEM-FC materials for automotive applications. A method to efficiently and accurately measure perfluorosulfonic acid distributions was developed and is being used to better understand how different loadings and preparation methods affect the ionomer distribution in the cathode. Progress towards an environmental cell capable of controlling the temperature and humidity of a PEM-FC sample in the STXM is described. Methods for studying the 3D chemical structure of PEM-FC are outlined

  2. Diamond-anvil cell for radial x-ray diffraction

    International Nuclear Information System (INIS)

    Chesnut, G N; Schiferl, D; Streetman, B D; Anderson, W W

    2006-01-01

    We have designed a new diamond-anvil cell capable of radial x-ray diffraction to pressures of a few hundred GPa. The diffraction geometry allows access to multiple angles of Ψ, which is the angle between each reciprocal lattice vector g(hkl) and the compression axis of the cell. At the 'magic angle', Ψ∼54.7 0 , the effects of deviatoric stresses on the interplanar spacings, d(hkl), are significantly reduced. Because the systematic errors, which are different for each d(hkl), are significantly reduced, the crystal structures and the derived equations of state can be determined reliably. At other values of Ψ, the effects of deviatoric stresses on the diffraction pattern could eventually be used to determine elastic constants

  3. Perforated ray cells in the wood of roots and branches of cerrado species from Brazil

    OpenAIRE

    Sonsin, Julia Oliveira [UNESP; Machado, Silvia Rodrigues [UNESP; Marcati, Carmen Regina [UNESP

    2008-01-01

    Perforated ray cells (PRCs) are recorded here for the first time in the roots and branches of Schefflera vinosa, Caryocar brasiliense, Acosmium subelegans, Byrsonima basiloba, B. coccolobifolia, B. verbascifolia and Alibertia concolor which occur in Pratania's cerrado (SP, Brazil). PRCs are larger than normal ray cells, occurring isolated or in groups of two or more in the same ray, and are present predominantly in the uniseriate portion of multiseriate rays in all species studied. In the roo...

  4. The irradiation effects of ultraviolet rays on Leptospira cells

    International Nuclear Information System (INIS)

    Maeda, Hidezo

    1982-01-01

    The irradiation effects of ultraviolets rays (UV) on leptospira cells were investigated. Four serovar strains of Genus Leptospira ; L. copenhageni, L. canicola, L. biflexa and L. illini were used. A sterilization lamp (Toshiba-GL-15) were lighted at intervals of 90mm on the sample fluid for several minutes. Loss of motility, survival growth and morphological damages were recognized under several conditions. The medium conditions were important, that is, the Korthof's medium was less effective than phosphate buffered saline (PBS). The irradiation time was also important, that is, L. canicola cells in PBS lost their motility and survive ability within 300sec. of irradiation, however, much more time, such as 1.200sec. was necessary in Korthof's medium. This phenomenon may be depended upon defensibility of albumin in the latter. Among the strains, L. biflexa cells showed the highest resistance in loss of motility and survive ability, and other three strains were inferior. The remarkable efects of cellular structures were also seen in the materials with 30 min. of irradiation, in both immediate time or after 24h incubation. The damages observed after 24th of irradiation were much more drastic than those of immediate time. No effect could be seen on the cells suspended in the Korthof's medium irradiated for 24h. Regarding morphological effect, there appeared relaxation of helical body, spherical body and semighost as the immediate changes. Structural damages were recognized as the collapse of cell body, such as scattering of capsule, release of axial flagella, loss or change of cytoplasmic density and break down of wall membrane complex. These phenomena were regarded as the indirect effects of UV-irradiation and autolysis in a post-mortem change. (author)

  5. Effect of combined treatments of pepleomycin with x-ray in cultured cells of a mouse squamous cell carcinoma

    International Nuclear Information System (INIS)

    Yokota, Masahiko; Wakamatsu, Yoshiko; Sairenji, Eiko; Ohara, Hirosi.

    1986-01-01

    Cultured SQ-1979 cells of C3H mouse squamous cell carcinomas in logarithmic growth phase were treated with either pepleomycin (PEP) or bleomycin (BLM), alone or in combination with X-rays. The lethal effect of PEP on the SQ cells was greater than that of BLM. The survival curves of the cells were biphasic at concentrations examined (5 to 60 μg/ml) of PEP. The survival depended on the concentration and treatment time up to 3 hr. The cells treated with BLM showed biphasic survival curves also. Regarding combined effects of either PEP or BLM and X-rays, there was no significant difference in the survival curves between the group with X-rays and the group with X-rays and drug. When a drug was given 4 hr after exposure to X-rays rather than before that, synergistic action of the drug and X-rays was attained. This was marked for PEP. (Namekawa, K.)

  6. Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

    International Nuclear Information System (INIS)

    Favali, M.A.; Sartorato, P.; Serafini-Fracassini, D.

    1984-01-01

    Parenchyma cells of dormant tubers of Helianthus tuberosus L. cv. OB 1 (Jerusalem artichoke) contain a very low amount of hormones, therefore they respond to 2.4-D or IAA treatment by dividing and synthesizing RNA, DNA, and polyamines. In particular the activation of the dormant tissues induces an early synthesis of DNA, which reaches the maximum at 3 hours, much before the beginning of the S phase (12 hours). By supplying [6- 3 H] thymidine and carrying out electron microscopic autoradiography, we were able to determine that plastids and mitochondria were the organelles responsible for this early synthesis while the DNA in the nucleus first appeared labeled at 15 hours. In addition, ultrastructural observations carried out to compare the dormant cells with activated ones, showed an increase in the nucleolar volume, a different organization of the tubular complex of the plastids and several other ultrastructural changes which indicate that at 3 hours some fundamental metabolic processes are already active; they become even more evident later on. The implication of these results in the physiology of the tuber cells during activation are discussed. (Author)

  7. Ultrastructure and autoradiography of dormant and activated parenchyma of Helianthus tuberosus

    Energy Technology Data Exchange (ETDEWEB)

    Favali, M.A.; Sartorato, P. (Padua Univ. (Italy)); Serafini-Fracassini, D. (Bologna Univ. (Italy))

    1984-01-01

    Parenchyma cells of dormant tubers of Helianthus tuberosus L. cv. OB/sup 1/ (Jerusalem artichoke) contain a very low amount of hormones, therefore they respond to 2.4-D or IAA treatment by dividing and synthesizing RNA, DNA, and polyamines. In particular the activation of the dormant tissues induces an early synthesis of DNA, which reaches the maximum at 3 hours, much before the beginning of the S phase (12 hours). By supplying (6-/sup 3/H) thymidine and carrying out electron microscopic autoradiography, we were able to determine that plastids and mitochondria were the organelles responsible for this early synthesis while the DNA in the nucleus first appeared labeled at 15 hours. In addition, ultrastructural observations carried out to compare the dormant cells with activated ones, showed an increase in the nucleolar volume, a different organization of the tubular complex of the plastids and several other ultrastructural changes which indicate that at 3 hours some fundamental metabolic processes are already active; they become even more evident later on. The implication of these results in the physiology of the tuber cells during activation are discussed.

  8. Resistance to alveolar shape change limits range of force propagation in lung parenchyma.

    Science.gov (United States)

    Ma, Baoshun; Smith, Bradford J; Bates, Jason H T

    2015-06-01

    We have recently shown that if the lung parenchyma is modeled in 2 dimensions as a network of springs arranged in a pattern of repeating hexagonal cells, the distortional forces around a contracting airway propagate much further from the airway wall than classic continuum theory predicts. In the present study we tested the hypothesis that this occurs because of the negligible shear modulus of a hexagonal spring network. We simulated the narrowing of an airway embedded in a hexagonal network of elastic alveolar walls when the hexagonal cells of the network offered some resistance to a change in shape. We found that as the forces resisting shape change approach about 10% of the forces resisting length change of an individual spring the range of distortional force propagation in the spring network fell of rapidly as in an elastic continuum. We repeated these investigations in a 3-dimensional spring network composed of space-filling polyhedral cells and found similar results. This suggests that force propagation away from a point of local parenchymal distortion also falls off rapidly in real lung tissue. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Effect on pancreatic beta cells and nerve cells by low let x-ray

    Energy Technology Data Exchange (ETDEWEB)

    Park, Kwang Hun [Dept. of Nuclear Medicine, Kyungbuk National University Hospital, Daegu (Korea, Republic of); Kim, Kgu Hwan [Dept. of Radiological Technology, Daegu health College, Daegu (Korea, Republic of)

    2014-03-15

    Cultured pancreatic beta cells and nerve cells, it is given normal condition of 10% FBS (fetal bovine serum), 11.1 mM glucose and hyperglycemia condition of 1% FBS, 30 mM glucose. For low LET X-ray irradiated with 0.5 Gy/hr dose-rate(total dose: 0.5 to 5 Gy). Survival rates were measured by MTT assay. When non irradiated, differentiated in the pancreatic beta cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a small reduction. However increasing the total dose of X-ray, the survival rate of normal conditions decreased slightly compared to the survival rate of hyperglycemia conditions, the synergistic effect was drastically reduced. When non irradiated, undifferentiated in the nerve cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a large reduction. As the cumulative dose of X-ray normal conditions and hyperglycemia were all relatively rapid cell death. But the rate of decreased survivals by almost parallel to the reduction proceed and it didn't show synergistic effect.

  10. Isolation of cell cycle-dependent gamma ray-sensitive Chinese hamster ovary cell

    International Nuclear Information System (INIS)

    Stamato, T.D.; Weinstein, R.; Giaccia, A.; Mackenzie, L.

    1983-01-01

    A technique for the isolation of gamma ray-sensitive Chinese hamster ovary (CHO) cell mutants is described, which uses nylon cloth replica plating and photography with dark-field illumination to directly monitor colonies for growth after gamma irradiation. Two gamma ray-sensitive mutants were isolated using this method. One of these cells (XR-1) had a two-slope survival curve: an initial steep slope and then a flattening of the curve at about 10% survival. Subsequently, it was found that this cell is sensitive to gamma irradiation in G1, early S, and late G2 phases of the cell cycle, whereas in the resistant phase (late S phase) its survival approaches that of the parental cells. The D37 in the sensitive G1 period is approximately 30 rads, compared with 300 rads of the parental cell. This mutant cell is also sensitive to killing by the DNA breaking agent, bleomycin, but is relatively insensitive to UV light and ethyl methane sulfonate, suggesting that the defect is specific for agents that produce DNA strand breakage

  11. Differences in responses to X-ray exposure between osteoclast and osteoblast cells

    International Nuclear Information System (INIS)

    Zhang, Jian; Wang, Ziyang; Wu, Anqing; Nie, Jing; Pei, Hailong; Hu, Wentao; Wang, Bing; Shang, Peng; Li, Bingyan; Zhou, Guangming

    2017-01-01

    Radiation-induced bone loss is a potential health concern for cancer patients undergoing radiotherapy. Enhanced bone resorption by osteoclasts and decreased bone formation by osteoblasts were thought to be the main reasons. In this study, we showed that both pre-differentiating and differentiating osteoclasts were relatively sensitive to X-rays compared with osteoblasts. X-rays decreased cell viability to a greater degree in RAW264.7 cells and in differentiating cells than than in osteoblastic MC3T3-E1 cells. X-rays at up to 8 Gy had little effects on osteoblast mineralization. In contrast, X-rays at 1 Gy induced enhanced osteoclastogenesis by enhanced cell fusion, but had no effects on bone resorption. A higher dose of X-rays at 8 Gy, however, had an inhibitory effect on bone resorption. In addition, actin ring formation was disrupted by 8 Gy of X-rays and reorganized into clusters. An increased activity of Caspase 3 was found after X-ray exposure. Actin disorganization and increased apoptosis may be the potential effects of X-rays at high doses, by inhibiting osteoclast differentiation. Taken together, our data indicate high radiosensitivity of osteoclasts. X-ray irradiation at relatively low doses can activate osteoclastogenesis, but not osteogenic differentiation. The radiosensitive osteoclasts are the potentially responsive cells for X-ray-induced bone loss.

  12. Damage effect of γ-rays on bacillus subtilis vegetative Cells

    International Nuclear Information System (INIS)

    Chen Xiaoming; Liu Fang; Zhang Jianguo; Yan Wanli; Zheng Chun; Li Xiaoyan

    2011-01-01

    In order to investigate the damage effects of γ-rays at cell and molecular level, Bacillus subtilis vegetative cells were irradiated by 60 Co γ-rays at different absorbed doses. The cell survival rate was examined with the standard plate-count method. The intracellular SOD activity was measured by SOD kit through xanthine oxidase method. DNA double-strand breaks were analyzed by pulsed-field gel electrophoresis (PFGE). The cell survival rate decreases when γ-rays dose increases. A clear relation could not be found between intracellular SOD activity and absorbed dose. The DNA release percentage value and break level value increase obviously with γ-rays dose. Cell survival rate is related to DNA double-strand breaks level. It can be concluded that γ-rays have obviously damage effect on Bacillus subtilis vegetative cell, and the damage effect changes with SOD activity and DSB. (authors)

  13. Tumour-cell killing by X-rays and immunity quantitated in a mouse model system

    International Nuclear Information System (INIS)

    Porteous, D.D.; Porteous, K.M.; Hughes, M.J.

    1979-01-01

    As part of an investigation of the interaction of X-rays and immune cytotoxicity in tumour control, an experimental mouse model system has been used in which quantitative anti-tumour immunity was raised in prospective recipients of tumour-cell suspensions exposed to varying doses of X-rays in vitro before injection. Findings reported here indicate that, whilst X-rays kill a proportion of cells, induced immunity deals with a fixed number dependent upon the immune status of the host, and that X-rays and anti-tumour immunity do not act synergistically in tumour-cell killing. The tumour used was the ascites sarcoma BP8. (author)

  14. Single cell low dose studies of bystander cell killing with targeted ultrasoft x-rays

    International Nuclear Information System (INIS)

    Schettino, G.; Prise, K.M.; Folkard, M.; Vojnovic, B.; Michael, B.D.; Wu, L.; Held, K.D.

    2003-01-01

    Full text: Bystander responses have attracted considerable interest in the recent years and several investigations have reported a binary behavior with the effect triggered by very small doses and immediately reaching a plateau. The Ultrasoft X-ray Microprobe in operation at the GCI is a facility designed to precisely assess the biological response of individual cells in vitro irradiated with a sub-micron size X-ray beam . Although recent improvements have upgrade the facility with AlK and TiK X-rays, most of the bystander studies have been performed using CK X-rays of 278 eV. The high sensitivity and the accurate irradiation and revisiting of the individual samples allowed us to investigate specific characteristics of the bystander phenomenon. In particular, evidences of a dose dependency of cell killing by bystander effect have been found at doses below 0.2 Gy where no differences is observed between all cell and single cell irradiation. Recent improvements have also allowed us to individually identify the phase of the cell cycle of all samples exposed. Although the G2-S phase have been found the most sensitive in responding to the bystander signal (a factor of 1.3), cells in the G1 phase also respond significantly while the phase of the irradiated cell doesn't seem to play a critical role. The time scale of the bystander effect has also been investigated by irradiating the same sample(s) twice with a few hours gap between exposures. Results indicate that the bystander signal is transmitted within a few minutes from the irradiation as replacing the medium immediately after irradiation does not influence the response, and it doesn't depend on the number of cells irradiated (up to 5). However, after a resting time of a few hours (3 h), the system seems to reset itself and a second irradiation has been shown to trigger a further bystander effect. Finally, by considering the total amount of energy deposited in to the sample population as critical parameter (instead

  15. Morphological variation of the kidney secondary to junctional parenchyma on ultrasound

    International Nuclear Information System (INIS)

    Lee, Ji Yoon; Park, Byeong Ho; Nam, Kyeong Jin; Choi, Jong Cheol; Koo, Bong Sig; Kim, Jou Yeoun; Ahn, Seung Eon; Lee, Yung Il

    1996-01-01

    To evaluate the prevalance of morphological variation of the kidney secondary to junctional parenchyma, as well as to analyze the ultrasonographic features of junctional parenchyma. Two hundred and eighty two kidneys of 141 patient without clinical or radiologic evidence of renal disease were prospectively analysed using ultrasound. In all patients, ultrasonograms were obtained in sagittal, coronal and transaxial planes. The kidney was considered to have morphological variation if the ultrasonogram demonstrated junctional parenchymal defect of line ; those showing such variation were classified as one of three types : continuous, discontinuous, or junctional parenchymal line or defect without junctional parenchyma. The prevalance and ultrasonographic features of the kidneys were evaluated. Morphological variation was noted in 71 cases(25%). the continuous type accounted for 54% of these, the discontinuous type for 38%, and junctional parenchymal defect or line without junctional parenchyma for 8%. In all cases, junctional parenchyma was located approximately at the junction of the upper and middle third of the kidney, and had the same echogenecity as the renal cortex. An understanding of the morphological variation of the kidney resulting from junctional renal parenchyma would be helpful in differentiating pseudotumor from true renal neoplasm

  16. Effect of antioxidants on x-ray induced DNA SSB and DSB in different cell systems

    International Nuclear Information System (INIS)

    Ramadu, Kadem

    1998-01-01

    The effect of x-ray radiation or antioxidants such as actinomycin D, cycloheximide and mitomycin C is studied on CHO, BHK and HeLa cells. X-ray radiation caused DNA single strand breaks (SSB) and double strand breaks (DSB) are prevented by cycloheximide and actinomycin-D. The DSB and SSB are significant in the case of x-ray radiation in combination with MMC, but different with actinomycin-D and cycloheximide in combination with x-ray radiation which causes less number of SSB and DSB. The ISC is observed more with x-ray radiation in combination with antioxidants mitomycin C (MMC) than that of cycloheximide and actinomycin-D, which individually causes inhibition of ISC induced by x-ray radiation. This observation proves that the MMC has an additive effect on x-ray induced ISC during cell proliferation. During cell proliferation, cell viability is observed with x-ray radiation and antioxidants which are dependent on the cell cycle phase. However, in the control cells, the initial Go-phase has shown negligible difference in percent cell viability thereby during S-phase gradual increase in the cell viability, and cell proliferation have been found to be stopped at G2+M-phase. On the contrary, cell viability and the extent of cell proliferation with x-ray radiation in combination with MMC have shown more damage (OH-damage) than is caused by x-ray radiation and MMC, separately. But, the fact is that actinomycin-D and cycloheximide act as antioxidants preventing thereby free radical formation and cell death, caused by x-ray radiation. During cell proliferation, cells observed from S and (G2+M) phase exhibit difference in cell viability in all the treatments alone and in combination. HeLa cells have been found insensitive to x-ray radiation and could be ascribed to the presence of glutathione transferase, which is less in CHO/BHK cell line. (author)

  17. 9-β-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays

    International Nuclear Information System (INIS)

    Heaton, D.

    1992-06-01

    The effect of 9-β-arabinofuranosyladenine (ara-A) on sensitivity to the deleterious effects of x-rays was studied in six squamous cell carcinoma cell lines. Three lines were relatively radioresistant, having D 0 values of 2.31 to 2.89 Gy, and the other three lines were relatively radiosensitive, having D 0 values of between 1.07 and 1.45 Gy. Ara-A (50 or 500 μM) was added to cultures 30 min prior to irradiation and removed 30 min after irradiation, and sensitivity was measured in terms of cell survival. The radiosensitizing effect of ara-A was very dependent on the inherent radiosensitivity of the tumor cell line. Fifty micromolar concentrations of ara-A sensitized only the two most radioresistant lines, SCC-12B.2 and JSQ-3. Five hundred micromolar concentrations of ara-A sensitized the more sensitive cell lines, SQ-20B and SQ-9G, but failed to have any effect on the radiation response of the two most sensitive cell lines, SQ-38 and SCC-61. Concentrations of ara-A as low as 10 μM were equally efficient in inhibiting DNA synthesis in all six cell lines. These results suggest that the target for the radiosensitizing effect of ara-A is probably related to the factor controlling the inherent radiosensitivity of human tumor cells. Therefore, ara-A might be useful in overcoming radiation resistance in vivo

  18. 9-{beta}-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Heaton, D. [Rush Univ. Medical Center, Chicago, IL (United States). Therapeutic Radiology; Mustafi, R. [Chicago Univ., IL (United States). Dept. of Radiation and Cellular Oncology; Schwartz, J.L. [Chicago Univ., IL (United States). Dept. of Radiation and Cellular Oncology]|[Argonne National Lab., IL (United States)

    1992-06-01

    The effect of 9-{beta}-arabinofuranosyladenine (ara-A) on sensitivity to the deleterious effects of x-rays was studied in six squamous cell carcinoma cell lines. Three lines were relatively radioresistant, having D{sub 0} values of 2.31 to 2.89 Gy, and the other three lines were relatively radiosensitive, having D{sub 0} values of between 1.07 and 1.45 Gy. Ara-A (50 or 500 {mu}M) was added to cultures 30 min prior to irradiation and removed 30 min after irradiation, and sensitivity was measured in terms of cell survival. The radiosensitizing effect of ara-A was very dependent on the inherent radiosensitivity of the tumor cell line. Fifty micromolar concentrations of ara-A sensitized only the two most radioresistant lines, SCC-12B.2 and JSQ-3. Five hundred micromolar concentrations of ara-A sensitized the more sensitive cell lines, SQ-20B and SQ-9G, but failed to have any effect on the radiation response of the two most sensitive cell lines, SQ-38 and SCC-61. Concentrations of ara-A as low as 10 {mu}M were equally efficient in inhibiting DNA synthesis in all six cell lines. These results suggest that the target for the radiosensitizing effect of ara-A is probably related to the factor controlling the inherent radiosensitivity of human tumor cells. Therefore, ara-A might be useful in overcoming radiation resistance in vivo.

  19. Neutrophils Infiltrate the Spinal Cord Parenchyma of Rats with Experimental Diabetic Neuropathy

    Directory of Open Access Journals (Sweden)

    Victoria L. Newton

    2017-01-01

    Full Text Available Spinal glial cell activation and cytokine secretion have been implicated in the etiology of neuropathic pain in a number of experimental models, including diabetic neuropathy. In this study, streptozotocin- (STZ- induced diabetic rats were either untreated or treated with gabapentin (50 mg/kg/day by gavage for 2 weeks, from 6 weeks after STZ. At 8 weeks after STZ, hypersensitivity was confirmed in the untreated diabetic rats as a reduced response threshold to touch, whilst mechanical thresholds in gabapentin-treated diabetic rats were no different from controls. Diabetes-associated thermal hypersensitivity was also ameliorated by gabapentin. We performed a cytokine profiling array in lumbar spinal cord samples from control and diabetic rats. This revealed an increase in L-selectin, an adhesion molecule important for neutrophil transmigration, in the spinal cord of diabetic rats but not diabetic rats treated with gabapentin. Furthermore, we found an increase in the number of neutrophils present in the parenchyma of the spinal cord, which was again ameliorated in gabapentin-treated diabetic rats. Therefore, we suggest that dysregulated spinal L-selectin and neutrophil infiltration into the spinal cord could contribute to the pathogenesis of painful diabetic neuropathy.

  20. Effects of BST and high energy diet on gene expression in mammary parenchyma of dairy heifers

    Directory of Open Access Journals (Sweden)

    Betina Joyce Lew

    2013-07-01

    Full Text Available The objective of this study was to determine the effects of dietary energy and recombinant bovine somatotropin (bST injection to identify genes that might control mammogenesis. Total RNA was extracted from the parenchymal tissue of 32 heifers randomly assigned to one of four treatments: two diets (a standard diet and a high energy, high protein diet, each with or without bST. To perform microarray experiments, RNA samples were pooled (2 animals/pool before reverse transcription and labeling with Cy3 or Cy5. A 4-node loop design was used to examine the differential gene expression among treatments using a bovine-specific cDNA microarray (National Bovine Functional Genomics Consortium Library, NBFGC containing 18,263 unique expressed sequence tags (EST. Significance levels of differential gene expression among treatments were assessed using a mixed model approach. Injection of bST altered the expression of 12 % of the genes on NBFGC slide related to tissue development, whereas 6% were altered by diet. Administration of bST increases the expression of genes positively related to cell proliferation and mammary parenchyma to a greater extent than a high energy diet.

  1. The compartments of the parenchyma of the lymph nodes in newborn bull calves of domestic cattle (Bos taurus

    Directory of Open Access Journals (Sweden)

    P. N. Gavrilin

    2017-04-01

    zones of the second morphotype, predominate T-dependent zones, the relative volume of which considerably exceeds the volume of B-dependent zones (lymphoid nodules: in the superficial somatic lymph nodes by 14–30 times, profound somatic by 12–14 times, somatovisceral by 6–7 times and visceral by 4.5–5.5 times. We determined that lymphatic nodules can form in different parts of compartments: in the interfollicular zone and paracortical cords of all lymph nodes and in the medullary cords of the visceral lymph nodes. The study shows that the parenchyma of the lymph nodes of newborn bull calves has a high degree of maturity, contains a full set of structural markers of immunocompetence, among which predominate the components that support lymphocyte migration, antigen detection and accumulation of plasma cells.

  2. γ-ray dose rate effect in DNA double-strand break repair deficient murine cells

    International Nuclear Information System (INIS)

    Li Liya; Li Peiwen

    2002-01-01

    Objective: To analyze the dose rate effect and potentially lethal damage repair in DNA double-strand break repair deficient murine cells (SCID) irradiated by γ-ray. Methods: The wild type (CB.17+/+) and SCID cells were exposed to γ-ray at high and low dose rates. The high dose rate exposure was fractionated into two equal doses at 24 h intervals. The survival rates of irradiated cells were calculated by clone-forming analysis. Results: When γ-ray was given to wild type (CB.17+/+) cells in two fractions at 24 h intervals, the survival rate was significantly higher than that when the same total dose was given singly. In contrast, there was no difference in the survival rates between the single and fractionated exposure in SCID cells. SCID cells were more sensitive than CB.17+/+ cells to both low and high dose rates γ-ray exposure for cell killing. The survival rate by low dose rate exposure was significantly higher than that by high dose rate exposure, not only in CB.17+/+ cells but also in SCID cells. Conclusions: SCID cells are deficient in repairing γ-ray induced double-strand breaks. There is dose rate effect in both SCID and CB.17+/+ cells

  3. Relationship between renal cortex and parenchyma thickness and renal function: study with CT measurement

    International Nuclear Information System (INIS)

    Xu Yufeng; Tang Guangjian; Jiang Xuexiang

    2006-01-01

    Objective: To study the relationship between renal morphology and renal function, and to assess the value of CT as a criterion to grade renal function. Methods: Enhancement CT were performed in 89 patients with no local renal disease whose split renal glomerular filtration rates (GFR) were measured by renal dynamic imaging with 99 Tc m -DTPA. The 178 kidneys were divided into normal renal function, mild and severe renal impairment groups according to renal function. Differences between three groups respect to the mean thickness of renal cortex and parenchyma were assessed by ANOVA. Using Pearson's correlation test, the correlation between the renal cortex, parenchyma thicknesses and renal GFR were examined. The value of CT in predicting renal function was assessed by using ROC analysis. Results: The renal cortex thicknesses of normal renal function, mild and severe renal impairment groups were (5.9±1.1), (4.6± 1.1), and (3.3±1.0) mm respectively, and the renal parenchyma thicknesses were (26.3±4.2), (21.3±4.6), (16.2±4.6) mm. There were significant differences of renal cortex, parenchyma thicknesses between 3 groups (cortex F=54.78, P<0.01; parenehyma F=43.90, P<0.01). The thicknesses of renal cortex (r=0.752, P<0.01), parenchyma (r=0.738, P<0.01) had positive linear correlation with renal function. ROC analysis of the renal cortex thicknesses measured by CT in predicting mild and severe renal impairment showed that the Az was 0.860 and 0.905 respectively, whereas that of parenchyma was 0.868 and 0.884. Conclusion: The thicknesses of renal cortex, parenchyma measured by CT can reflect renal function. CT was a supplementary method to assess renal function. (authors)

  4. X-ray-induced in vitro neoplastic transformation of human diploid cells

    International Nuclear Information System (INIS)

    Borek, C.

    1980-01-01

    Techniques have recently been developed to identify and score quantitatively neoplastic transformation caused by x-rays in cultured cells derived from rodents. The present report describes for the first time the neoplastic transformation in vitro of human diploid cells by x-ray irradiation into cells which can progress in vitro into advanced stages of neoplastic development, namely, to form colonies in agar and give rise to tumors when injected into nude mice

  5. Standardisation of liver MDCT by tracking liver parenchyma enhancement to trigger imaging

    International Nuclear Information System (INIS)

    Brodoefel, H.; Tognolini, A.; Zamboni, G.A.; Gourtsoyianni, S.; Raptopoulos, V.; Claussen, C.D.

    2012-01-01

    To assess parenchymal bolus-triggering in terms of liver enhancement, lesion-to-liver conspicuity and inter-image variability across serial follow-up MDCTs. We reviewed MDCTs of 50 patients with hepatic metastases who had a baseline CT and two follow-up examinations. In 25 consecutive patients CT data acquisition was initiated by liver parenchyma triggering at a 50-HU enhancement threshold. In a matched control group, imaging was performed with an empirical delay of 65 s. CT attenuation values were assessed in vessels, liver parenchyma and metastasis. Target lesions were classified according to five enhancement patterns. Compared with the control group, liver enhancement was significantly higher with parenchyma triggering (59.8 ± 7.6 HU vs. 48.8 ± 11.2 HU, P = 0.0002). The same was true for conspicuity (liver parenchyma - lesion attenuation) of hypo-enhancing lesions (72.2 ± 15.9 HU vs. 52.7 ± 19.4 HU, P = 0.0006). Liver triggering was associated with reduced variability for liver enhancement among different patients (P = 0.035) and across serial follow-up examinations in individual patients (P < 0.0001). The number of patients presenting with uniform lesion enhancement pattern across serial examinations was significantly higher in the triggered group (20 vs. 11; P = 0.018). Liver parenchyma triggering provides superior lesion conspicuity and improves standardisation of image quality across follow-up examinations with greater uniformity of enhancement patterns. (orig.)

  6. The Rare Benign Lesion That Mimics a Malignant Tumor in Breast Parenchyma: Nodular Fasciitis of the Breast

    Directory of Open Access Journals (Sweden)

    Hilal Erinanc

    2018-01-01

    Full Text Available We herein report the clinical and pathological findings of a rare case of nodular fasciitis in the breast parenchyma of a 48-year-old female. Because of potentially malignant findings on ultrasonography and during clinical examination, the patient underwent an excisional biopsy. Histologically, the lesion was composed of spindle to round shaped cells arranged in short bundles in a storiform pattern. Immunohistochemically, the cells were positive for vimentin and SMA and negative for desmin, S100, and CD34. Based on these morphological and immunohistochemical features, a diagnosis of nodular fasciitis was made. We emphasize that nodular fasciitis of the breast may show clinical features and imaging findings similar to those of breast cancer. The histopathologic diagnosis of nodular fasciitis can also be challenging. The purpose of this case report is to highlight the characteristics and the differential diagnosis of this rare neoplasm.

  7. Use of backscattered electron imaging, X-ray microanalysis and X-ray microscopy in demonstrating physiological cell death

    International Nuclear Information System (INIS)

    Bowen, I.D.; Worrill, N.A.; Winters, C.A.; Mullarkey, K.

    1988-01-01

    The cytochemical localization of enzymatic activity by means of backscattered electron imaging (BEI) is reviewed and the application of BEI to changes in acid phosphatase and ATPase distribution during physiological (programmed) cell death in Heliothis midgut is explored. Programmed cell death entails the release of nascent free acid phosphatase as extracisternal hydrolase. This shift can readily be detected by means of the atomic number contrast imparted by BEI of the lead phosphatase reaction product, thus enabling the distribution of dying cells to be mapped. BEI is particularly useful in this context as it allows the examination of bulk specimens at low magnification. Death of cells is also accompanied by a collapse in ATPase activity which shows up as cytochemically negative areas in the X-ray microscope and by means of BEI. Acid phosphatase in normal cells is localized in the apical microvilli and lysosomes. Senescent or dying cells, however, clearly show a basally situated free hydrolase which migrates throughout the cell. Parallel TEM results confirm that this enzyme is ribosomal and extracisternal rather than lysosomal in origin. ATPase activity is largely limited to the apical microvilli, although there is some activity associated with the basal plasma membranes. The apical ATPase, however is partially resistant to ouabain. Young and mature cells are positive although in the latter case some microvilli may be lost as the cells acquire a negative cap or dome. Inhibition by bromotetramizole indicates that apical activity is not to any significant extent contributed to by alkaline phosphatase. Degenerate or dead cells are negative and can be seen as a mozaic of black patches among normal cells when imaged by means of BEI or X-ray microscopy

  8. Hydrostatic pressure cells development for X-ray and neutron experiments

    International Nuclear Information System (INIS)

    Passamai Junior, Jose Luis

    2010-01-01

    It was developed and built two pressure cell original models in order to be applied in X-ray elastic scattering (X-ray diffraction), X-ray absorption and neutron scattering experiments (neutron diffraction) under hydrostatic pressure. For the first two experimental cases, where X-ray beam is used, the pressure cell built with two B 4 C anvil mounted in a CuBe body. The B 4 C anvil was prepared at CTA research center in order to present an enhanced X-ray transparence and hardness. The special detail and advantage of the CuBe cell with B 4 C anvil is that this cell can be also used to measure de AC magnetic susceptibility in situ. This special characteristic is highlight as new concept of labeled here as multipurpose pressure cell. A second type of cell pressure was developed in order to be used in neutron elastic scattering experiments, specific in neutron diffraction experiments. The neutron cell pressure was developed using carbon fibers composite to improve the mechanical resistance a cylindrical geometry. The B 4 C pressure cells were available to researches in LNLS. The neutron pressure cell was given to research staff of IPEN Nuclear Reactor. This work show details and draws of these two types of hydrostatic pressure cells. (author)

  9. X-ray-induced in vitro neoplastic transformation of human diploid cells

    International Nuclear Information System (INIS)

    Borek, C.

    1980-01-01

    The neoplastic transformation, in vitro, of human diploid cells by x-ray irradiation into cells which can progress, in vitro, into advanced stages of neoplastic development is described. The cells are shown to form colonies in agar and to give rise to tumours when injected into nude mice. (U.K.)

  10. Hydrostatic pressure cells development for X-ray and neutrons experiments

    International Nuclear Information System (INIS)

    Passamai Junior, Jose Luis; Pinheiro, Christiano J.G.; Orlando, Marcos Tadeu D.; Passos, Carlos A.C.; Rossi, Jesualdo L.; Mazzocchi, Vera L.; Parente, Carlos B.R.; Mestnik Filho, Jose; Martinez, Luis G.; Melo, Francisco C.L. de

    2011-01-01

    A set of hydrostatic pressure cells was specially developed in order to be applied in X-ray diffraction, X-ray absorption and neutron diffraction experiments. For the experiments where X-rays are used, the pressure cells are built in a CuBe alloy body with two B 4 C anvils in order to allow the low absorption of the radiation. The B 4 C anvils were specially prepared in CTA - Centro Tecnico Aeroespacial - Sao Jose dos Campos - Brazil, in order to present enhanced X-ray transparency and high hardness. One of the advantage of the CuBe-body cell with B 4 C anvil is that it can be also used under magnetic fields, for instance for measurements of AC magnetic susceptibility under high hydrostatic pressures. The X-ray cells work in transmission mode and present a 2 mm diameter hole for the beam path. The X-ray beam pass through the hole and outgoing to the detector positioned in front of the pressure cell. A second type of pressure cell was developed in order to be used in neutron elastic scattering experiments, especially in neutron diffraction experiments. The neutron cell pressure cell was constructed in Zirconium alloy reinforced with carbon fibers composite in order to improve the mechanical resistance of his cylindrical geometry. The B 4 C pressure cells are available to users of the techniques of X-ray diffraction and absorption in the Brazilian National Synchrotron Laboratory - LNLS, at Campinas City. The neutron pressure cell is available to users at the neutron powder diffraction facility installed at the Nuclear and Energy Research Institute - IPEN, Sao Paulo. In this work will be shown details and drawings of the two types of hydrostatic pressure cells. (author)

  11. Iron overload of human colon adenocarcinoma cells studied by synchrotron-based X-ray techniques

    NARCIS (Netherlands)

    Mihucz, Victor G.; Meirer, Florian; Polgári, Zsófia; Réti, Andrea; Pepponi, Giancarlo; Ingerle, Dieter; Szoboszlai, Norbert; Streli, Christina

    2016-01-01

    Fast- and slow-proliferating human adenocarcinoma colorectal cells, HT-29 and HCA-7, respectively, overloaded with transferrin (Tf), Fe(III) citrate, Fe(III) chloride and Fe(II) sulfate were studied by synchrotron radiation total-reflection X-ray spectrometry (TXRF), TXRF-X-ray absorption near edge

  12. Immune responses of dendritic cells after acquiring antigen from apoptotic hepatocholangioma cells caused by γ-ray

    International Nuclear Information System (INIS)

    Wu Gang; Gu Hongguang; Han Benli; Pei Xuetao

    2002-01-01

    Objective: To investigate the induction of cytotoxic T lymphocytes (CTLs) in antitumor responsiveness and therapeutic effects after dendritic cells (DCs) acquired antigen from apoptotic hepatocholangioma cells. Methods: DCs from blood mononuclear cells that maintain the characteristics of immaturity-anti-gen-capturing and-processing capacity were established in vitro by using granulocyte/macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Then, apoptosis in hepatocholangioma cells was induced with γ-radiation. The experimental groups included (1) co-culture of DCs, and apoptotic cancer cells and T cells; (2) co-culture of DCs necrotic cancer cells and T cells; (3) co-culture of DCs-cultured cancer cell and T cells. These cells were co-cultured for 7 days. DCs and T cell were enriched separately. Finally, antitumor response test was carried out. Results: These cells had typical dendritic morphology, expressed high levels of CD1a, B7 and acquired antigen from apoptotic cells caused by γ-rays and induced an increased T cell-stimulatory capacity in MLR. Conclusions: DCs obtained from blood mononuclear cells using GM-CSF and IL-4 and DCs can efficiently present antigen driven from apoptotic cells caused by γ-rays and induce T cells increasing obviously. It can probably become an effective approach of DC transduction with antigen

  13. A sample cell to study hydrate formation with x-ray scattering

    International Nuclear Information System (INIS)

    Conrad, Heiko; Lehmkuehler, Felix; Sternemann, Christian; Feroughi, Omid; Tolan, Metin; Simonelli, Laura; Huotari, Simo

    2009-01-01

    We present a new sample cell for measuring nonresonant inelastic x-ray scattering spectra of a tetrahydrofuran (THF)-water liquid mixture and THF hydrate. The hydrate is formed inside the cell after nucleation seeds have been offered by a special magnetic stirring mechanism. Hydrate formation was verified by wide angle x-ray scattering and nonresonant x-ray Raman scattering spectra at the oxygen K-edge. A broad range of scattering angles can be studied with this cell which is necessary for momentum transfer dependent inelastic x-ray scattering. This cell is ideal to examine other liquid hydrate formers or other liquid samples, which have to be mixed in situ during the measurements.

  14. Relative survival of hybrid x-ray-resistant, and normally sensitive mammalian cells exposed to x rays and protons under aerobic and hypoxic conditions

    International Nuclear Information System (INIS)

    Williams, J.R.; Gould, R.G.; Flynn, D.; Robertson, J.B.; Little, J.B.

    1978-01-01

    Survival of an x-ray-resistant hybrid cell line (HD 1 ) and a normally responsive cell line (H 4 ) have been compared when irradiated under induced hypoxia by both protons and X rays. The two cell lines are similarly protected when irradiated under hypoxic conditions with oxygen enhancement ratios of 2.8 and 2.7, respectively. The protection is consistent with a dose-modifying factor. No statistically significant difference is observed between cell inactivation by x rays and protons in either cell line, whether irradiated under aerobic or hypoxic conditions

  15. Effect of Smac gene on apoptosis of HeLa cells induced by γ-rays

    International Nuclear Information System (INIS)

    Zhao Baofeng; Tian Mei; Ruan Jianlei; Su Xu

    2007-01-01

    To explore the effect of Smac gene on apoptosis of HeLa cells induced by γ-ray and its possible mechanisms, the full length cDNA of Smac gene was transferred into HeLa cells. 24 h after transferring, the results of Western Blot indicated the expression of Smac was increased but the expression of Survivin decreased. After HeLa cells was irradiated by γ-rays, Smac gene transferred HeLa/Smac cells showed more cell apoptosis rates and the higher activity of Caspase-3 than vector transferred control HeLa/pcDNA3.1 cells. However, the damage and repair of DNA and the cell cycle don't change significantly, comparing HeLa/Smac cells with HeLa/pcDNA3.1 cells. (authors)

  16. Tissue distribution and deposition pattern of a cellulosic parenchyma-specific protein from cassava roots

    Directory of Open Access Journals (Sweden)

    Petrônio A.S. Souza

    1998-06-01

    Full Text Available A protein with a molecular mass of 22kDa was purified from the cellulosic parenchyma of cassava roots. The amino acid composition of the protein was determined and antibodies generated against the purified protein were used to show that the concentration of the protein remains unchanged during root "tuber" formation. By using a tissue printing technique, as well as western blot, it was shown that the cellulosic parenchyma was the only root tissue in which the protein was deposited.

  17. Computer analysis of the amount functioning renal parenchyma according scintigraphy with 99mTc - DMSA

    International Nuclear Information System (INIS)

    Nyikolov, M.O.; Suprunyuk, D.O.; Chizhevs'kij, V.B.; Kamyins'ka, A.L.; Makarenko, A.V.

    2014-01-01

    To assess the definition of information values of focal changes in the renal parenchyma as a fuzzy set according kidney scan with 99m Tc-DMSA. The results of kidney scan of 99m Tc-DMSA 15 patients. It is shown that it is advisable to determine the degree of damage to the renal parenchyma as a fuzzy set, it count lower, upper limits of defeat and 'average' rating. Segmentation algorithms developed scintigraphic imaging of the kidneys are informative, independent and requires their simultaneous use

  18. Photodynamic synchrotron x-ray therapy in Glioma cell using superparamagnetic iron nanoparticle

    Science.gov (United States)

    Kim, Hong-Tae; Kim, Ki-Hong; Choi, Gi-Hwan; Jheon, Sanghoon; Park, Sung-Hwan; Kim, Bong-Il; Hyodo, Kazuyuki; Ando, Masami; Kim, Jong-Ki

    2009-06-01

    In order to evaluate cytotoxic effects of secondary Auger electron emission(Photon Activation Therapy:PAT) from alginate-coated iron nanoparticles(Alg-SNP), Alg-SNP-uptaken C6 glioma cell lines were irradiated with 6.89/7.2 Kev synchrotron X-ray. 0-125 Gy were irradiated on three experimental groups including No-SNP group incubating without SNP as control group, 6hr-SNP group incubating with SNP for 6hr and ON-SNP group incubating with SNP overnight. Irradiated cells were stained with Acridine Orange(AO) and Edithium Bromide(EB) to count their viability with fluorescent microscopy in comparison with control groups. AO stained in damaged DNA, giving FL color change in X-ray plus SNP group. EB did not or less enter inside the cell nucleus of control group. In contrast, EB entered inside the cell nucleus of Alg-SNP group which means more damage compared with Control groups. The results of MTT assay demonstrated a X-ray dose-dependent reduction generally in cell viability in the experimental groups. 3 or 9 times increase in cell survival loss rate was observed at 6hr-SNP and ON-SNP groups, respectively compared to No-SNP control group in first experiment that was done to test cell survival rate at relatively lower dose, from 0 to 50 Gy. In second experiment X-ray dose was increased to 125 Gy. Survival loss was sharply decreased in a relatively lower dose from 5 to 25 Gy, and then demonstrated an exponentially decreasing behavior with a convergence until 125 Gy for each group. This observation suggests PAT effects on the cell directly by X-ray in the presence of Alg-SNP occurs within lower X-ray dose, and conventional X-ray radiation effect becomes dominant in higher X-ray dose. The cell viability loss of ON-SNP group was three times higher compared with that of 6hr-SNP group. In conclusion, it is possible to design photodynamic X-ray therapy study using a monochromatic x-ray energy and metal nanoparticle as x-ray sensitizer, which may enable new X-ray PDT to

  19. Cell Morphology Change by the Ultraviolet Ray Irradiation

    International Nuclear Information System (INIS)

    Park, Myung Joo; Matuo, Yoichirou; Akiyama, Yoko; Izumi, Yoshinobu; Nishijima, Shigehiro

    2009-01-01

    The effect of low doses of ultraviolet (UV) irradiation on morphology changes of cell has been studied based on the observation of the cell length. It was shown that UV-irradiated cell has different behavior in comparison with nonirradiated cell. From the histogram of cell-length distribution, it was confirmed that cell cycle of non irradiated cell was 28 hours, and that cell cycle of irradiated cell with dose of 20 Jm -2 was delayed (39 hours), while irradiated cell with 40 Jm -2 and 60 Jm -2 did not divide and kept growing continuously. It was supposed that in case of 20 Jm -2 of irradiation dose, the cell cycle was delayed because the checkpoint worked in order to repair DNA damage induced by generation of pyrimidine dimer, reactive oxygen species and so on. It was also supposed that in case of 40 Jm -2 and 60 Jm -2 of irradiation dose, overgrowth was induced because the checkpoint was not worked well. The morphology of overgrown cell was similar to that of normally senescent cell. Therefore, it was considered that cell senescence was accelerated by UV irradiation with irradiation doses of 40 Jm -2 and 60 Jm -2

  20. Streaming Model Based Volume Ray Casting Implementation for Cell Broadband Engine

    Directory of Open Access Journals (Sweden)

    Jusub Kim

    2009-01-01

    Full Text Available Interactive high quality volume rendering is becoming increasingly more important as the amount of more complex volumetric data steadily grows. While a number of volumetric rendering techniques have been widely used, ray casting has been recognized as an effective approach for generating high quality visualization. However, for most users, the use of ray casting has been limited to datasets that are very small because of its high demands on computational power and memory bandwidth. However the recent introduction of the Cell Broadband Engine (Cell B.E. processor, which consists of 9 heterogeneous cores designed to handle extremely demanding computations with large streams of data, provides an opportunity to put the ray casting into practical use. In this paper, we introduce an efficient parallel implementation of volume ray casting on the Cell B.E. The implementation is designed to take full advantage of the computational power and memory bandwidth of the Cell B.E. using an intricate orchestration of the ray casting computation on the available heterogeneous resources. Specifically, we introduce streaming model based schemes and techniques to efficiently implement acceleration techniques for ray casting on Cell B.E. In addition to ensuring effective SIMD utilization, our method provides two key benefits: there is no cost for empty space skipping and there is no memory bottleneck on moving volumetric data for processing. Our experimental results show that we can interactively render practical datasets on a single Cell B.E. processor.

  1. Reflection-mode x-ray powder diffraction cell for in situ studies of electrochemical reactions

    International Nuclear Information System (INIS)

    Roberts, G.A.; Stewart, K.D.

    2004-01-01

    The design and operation of an electrochemical cell for reflection-mode powder x-ray diffraction experiments are discussed. The cell is designed for the study of electrodes that are used in rechargeable lithium batteries. It is designed for assembly in a glove box so that air-sensitive materials, such as lithium foil electrodes and carbonate-based electrolytes with lithium salts, can be used. The cell uses a beryllium window for x-ray transmission and electrical contact. A simple mechanism for compressing the electrodes is included in the design. Sample results for the cell are shown with a Cu Kα source and a position-sensitive detector

  2. Inhibition of epidermal cell proliferation by borderline rays

    Energy Technology Data Exchange (ETDEWEB)

    Born, W [Freiburg Univ.; Daikeler, G

    1976-08-01

    Treatment of guinea pig flanks with very soft x-rays (borderline rays) directly caused a partial block of epidermal DNA synthesis which had been determined by measuring the /sup 3/H-Tdr incorporation. Higher doses and repeated applications would undoubtedly cause lasting damage to the tissue. The enhanced epidermal DNA synthesis which is sometimes observed should not be misinterpreted as a sign of a directly biopositive utilisation of the quantum energy supplied. Rather, it is a secondary repair process following initial phases of depression. A reparative increase in DNA synthesis may also occur as a primary process if the radiation is almost completely absorbed above the germinative layer.

  3. Effects of x-rays and bleomycin on cultured mammalian cells

    International Nuclear Information System (INIS)

    Masuda, Kouji; Takaki, Tosuke; Wakisaka, Shinichiro

    1982-01-01

    The cultured brain tumor cells and established cell lines, HeLa S3 and L5, were exposed to X-rays, with and without combinations of bleomycin, and the reproductive capacity and growth curves of these treated cells were assayed. No enhancement of the cell killing effect was observed when cells were treated with bleomycin following irradiation, while preliminary bleomycin treatment sensitized the cells to irradiation. No division delay was observed in cell reproductively surviving the bleomycin treatment, even though the concentrations of bleomycin were sufficient to reduce the survivals to less than 10%. An attempt to determine the conversion factor for evaluating X-ray doses in bleomycin equivalents failed because the order of the radiosensitivity of these cells was different from that of the sensitivity to bleomycin treatment. (author)

  4. Repair of X-ray-induced single-strand breaks by a cell-free system

    International Nuclear Information System (INIS)

    Seki, Shuji; Ikeda, Shogo; Tsutui, Ken; Teraoka, Hirobumi

    1990-01-01

    Repair of X-ray-induced single-strand breaks of DNA was studied in vitro using an exonuclease purified from mouse ascites sarcoma (SR-C3H/He) cells. X-ray-dose-dependent unscheduled DNA synthesis was primed by the exonuclease. Repair of X-ray-induced single-strand breaks in pUC19 plasmid DNA was demonstrated by agarose gel electrophoresis after incubating the damaged DNA with the exonuclease, DNA polymerase (Klenow fragment of DNA polymerase I or DNA polymerase β purified from SR-C3H/He cells), four deoxynucleoside triphosphates, ATP and DNA ligase (T4 DNA ligase or DNA ligase I purified from calf thymus). The present results suggested that the exonuclease is involved in the initiation of repair of X-ray-induced single-strand breaks in removing 3' ends of X-ray-damaged DNA. (author)

  5. Caffeine enhancement of x-ray killing in cultured human and rodent cells

    International Nuclear Information System (INIS)

    Waldren, C.A.; Rasko, I.

    1978-01-01

    A 16 to 20 hr postirradiation incubation with caffeine enhances x-ray killing of rodent and human cells. Cells tested were Chinese hamster ovary (CHO-K1), lung (CHL), V79, mouse L, HeLa S3, human fibroblasts (AF288, TC171, FS9, CRL1166), and a human-hamster hybrid. The effect of caffeine on the x-ray survival curve of these cells was to remove the initial shoulder without significantly altering the mean lethal dose (D 0 ). This action can be achieved at caffeine concentrations which of themselves cause less than 15% killing. In randomly growing CHO-K1 cells the caffeine-sensitive process occurs with a half-time of 2 to 5 hr after irradiation. These experiments indicate the existence in human and rodent cells of caffeine-inhibited genome repair for x-ray damage

  6. Autoradiographic study of gamma-ray induced unscheduled DNA synthesis in bean root meristem cells

    International Nuclear Information System (INIS)

    Liu Zhenshen; Qiu Quanfa; Chen Dongli

    1989-01-01

    The gamma-ray induced unscheduled DNA synthesis in root meristem cells of Vica faba was studied autoradiographically by calculating the number of cells with different 3H-thymidine labelling degree. It was found that the level of unscheduled synthesis in cells with intermediate dose (500 R) irradiation was higher than that in cells with lower dose (250 R) irradiation; however, higher dose (1000 R) irradiation would inhibit the reparative replication

  7. The mechanism of inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells

    International Nuclear Information System (INIS)

    Zhuang Yongzhi; Wang Junjie; Zhang Zhanchun; Jia Tingzhen

    2001-01-01

    Objective: To investigate the inhibitory effect of γ-ray irradiation on rat vascular smooth muscle cells (VSMCs). Methods: Dose-survival curve of VSMCs was figured by colony formation. The effect of γ-ray irradiation on viability and proliferation of VSMCs was observed by 3 H incorporation. Flow cytometry and DNA Ladder were used to detect the apoptosis effect of γ-ray irradiation on VSMCs. Results: The values of D 0 , D q , D 37 and N for VSMCs were 1.95 Gy, 1.76 Gy, 3.71 Gy and 2.47, respectively. The inhibitory effect of γ-ray irradiation on VSMCs proliferation was dose-dependent, being stronger along with increase of dose. VSMCs did not undergo apoptosis within 48 hours after γ-ray irradiation. Conclusion: γ-ray irradiation could inhibit the proliferation of VSMCs, the main mechanism of which is the killing effect and inhibition of mitosis of VSMCs

  8. Distinctive transforming genes in x-ray-transformed mammalian cells

    International Nuclear Information System (INIS)

    Borek, C.; Ong, A.; Mason, H.

    1987-01-01

    DNAs from hamster embryo cells and mouse C3H/10T1/2 cells transformed in vitro by x-irradiation into malignant cells transmit the radiation transformation phenotype by producing transformed colonies (transfectants) in two mouse recipient lines, the NIH 3T3 and C3H/101/2 cells, and in a rat cell line, the Rat-2 cells. DNAs from unirradiated cells or irradiated and visibly untransformed cells do not produce transformed colonies. The transfectant grow in agar and form tumors in nude mice. Treatment of the DNAs with restriction endonucleases prior to transfection indicates that the same transforming gene (oncogene) is present in each of the transformed mouse cells and is the same in each of the transformed hamster cells. Southern blot analysis of 3T3 or Rat-2 transfectants carrying oncogenes from radiation-transformed C3H/10T1/2 or hamster cells indicates that the oncogenes responsible for the transformation of 3T3 cells are not the Ki-ras, Ha-ras, N-ras genes, nor are they neu, trk, raf, abl, or fms. The work demonstrates that DNAs from mammalian cells transformed into malignancy by direct exposure in vitro to radiation contain genetic sequences with detectable transforming activity in three recipient cell lines. The results provide evidence that DNA is the target of radiation carcinogenesis induced at a cellular level in vitro. The experiments indicate that malignant radiogenic transformation in vitro of hamster embryo and mouse C3H/10T1/2 cells involves the activation of unique non-ras transforming genes, which heretofore have not been described

  9. Renal parenchyma thickness: a rapid estimation of renal function on computed tomography

    International Nuclear Information System (INIS)

    Kaplon, Daniel M.; Lasser, Michael S.; Sigman, Mark; Haleblian, George E.; Pareek, Gyan

    2009-01-01

    Purpose: To define the relationship between renal parenchyma thickness (RPT) on computed tomography and renal function on nuclear renography in chronically obstructed renal units (ORUs) and to define a minimal thickness ratio associated with adequate function. Materials and Methods: Twenty-eight consecutive patients undergoing both nuclear renography and CT during a six-month period between 2004 and 2006 were included. All patients that had a diagnosis of unilateral obstruction were included for analysis. RPT was measured in the following manner: The parenchyma thickness at three discrete levels of each kidney was measured using calipers on a CT workstation. The mean of these three measurements was defined as RPT. The renal parenchyma thickness ratio of the ORUs and non-obstructed renal unit (NORUs) was calculated and this was compared to the observed function on Mag-3 lasix Renogram. Results: A total of 28 patients were evaluated. Mean parenchyma thickness was 1.82 cm and 2.25 cm in the ORUs and NORUs, respectively. The mean relative renal function of ORUs was 39%. Linear regression analysis comparing renogram function to RPT ratio revealed a correlation coefficient of 0.48 (p * RPT ratio. A thickness ratio of 0.68 correlated with 20% renal function. Conclusion: RPT on computed tomography appears to be a powerful predictor of relative renal function in ORUs. Assessment of RPT is a useful and readily available clinical tool for surgical decision making (renal salvage therapy versus nephrectomy) in patients with ORUs. (author)

  10. Plant foods in the Upper Palaeolithic at Dolní Věstonice? Parenchyma redux

    Czech Academy of Sciences Publication Activity Database

    Pryor, A.; Steele, M.; Jones, M. K.; Svoboda, Jiří; Beresford-Jones, D. G.

    2013-01-01

    Roč. 87, č. 338 (2013), s. 971-984 ISSN 0003-598X Institutional support: RVO:68081758 Keywords : Czech Republic * Dolní Věstonice * upper palaeolithic * gravettian * archaeobotany * plant foods * parenchyma Subject RIV: AC - Archeology, Anthropology, Ethnology OBOR OECD: Archaeology Impact factor: 1.594, year: 2013

  11. Changes in energy metabolism of the juvenile Fasciola hepatica during its development in the liver parenchyma

    NARCIS (Netherlands)

    Tielens, A.G.M.; Heuvel, J.M. van den; Bergh, S.G. van den

    1982-01-01

    Juvenile Fasciola hepatica at different stages of development were isolated from the liver parenchyma of experimentally infected rats. Their energy metabolism was studied by incubation with D-[16-14C]glucose and compared with that of juveniles isolated immediately after in vitro emergence from the

  12. Influence of gamma radiation on the growth and metabolism ''in vitro'' culture of potato parenchyma

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Mazon Matanzo, M.P.

    1977-01-01

    The growth ''in vitro'' of the parenchyma tissues coming from control and irradiated potato tubers with doses of 3, 6, 9 and 12 Krad. is studied. At the end of a four months' cultivation period the cellular proliferation, respiratory activity, content in ascorbic acid, conductivity, and pH was studied. Some differences between control and irradiated tissues were observed. (author) [es

  13. Influence of gamma radiation on the growth and metabolism in vitro culture of potato parenchyma

    International Nuclear Information System (INIS)

    Fernandez Gonzalez, J.; Mazon Matanzo, M. P.

    1977-01-01

    The present work studies the growth in vitro of the parenchyma tissues coming from control and irradiated potato tubers with doses of 3, 6, 9 and 12 Krad. At the end of a four months cultivation period the cellular proliferation, respiratory activity, content in ascorbic acid, conductivity and ph was studied. Some differences between control and irradiated tissues were observed. (Author) 22 refs

  14. Elucidation of the mechanism of X-ray induced DNA duplication observed in human Gorlin cells

    International Nuclear Information System (INIS)

    Nomura, J.; Suzuki, N.; Kita, K.; Sugaya, S.

    2004-01-01

    A phenomenon in which DNA synthesis level increases rapidly after x-ray irradiation has found out in the cells which originate in Gorlin patients. A gene, by which an expression level changes after x-ray irradiation, is searched in the human Gorlin cells by the mRNA differential display method. The DNA synthesis level decreases in normal human cell after x-ray irradiation of 2 Gy dose, but increases twice in the Gorlin cell. Expression levels of gene SMT3A, however decrease clearly in the Gorlin cells after the irradiation. The relations between expression levels of gene SMT3M, a protein like ubichitin, and DNA synthesis levels are searched. DNA synthesis activity in normal human cells, which are treated by antisese oligonucleotide and suppressed expression of the genes SMT3A, increases after x-ray irradiation. An increase of the DNA synthesis level after the irradiation is not a phenomenon in particular cells, but indicates the possibility of general phenomena in normal human cells. It is reported that the gene SMT3A combines with a glycosylase which operates in DNA repairing process. The protein modification of gene SMT3A indicates a possibility for controlling of stress protection mechanism in the cells. (M. Suetake)

  15. Inactivation of HTB63 human melanoma cells by irradiation with protons and gamma rays.

    Science.gov (United States)

    Ristic-Fira, Aleksandra; Petrovic, Ivan; Todorovic, Danijela; Koricanac, Lela; Vujèic, Miroslava; Demajo, Miroslav; Sabini, Gabriella; Cirrone, Pablo; Cuttone, Giacomo

    2004-12-01

    The effects of single irradiation with gamma rays and protons on HTB63 human melanoma cell growth were compared. The exponentially growing cells were irradiated with gamma rays or protons using doses ranging from 2-20 Gy. At 48 h of post-irradiation incubation under standard conditions, cell survival and induction of apoptotic cell death were examined. The best effect of the single irradiation with gamma rays was the reduction of cell growth by up to 26% (p=0.048, irradiation vs. control), obtained using the dose of 16 Gy. The same doses of proton irradiation, having energy at the target of 22.6 MeV, significantly inhibited melanoma cell growth. Doses of 12 and 16 Gy of protons provoked growth inhibition of 48.9% (p=0.003, irradiation vs. control) and 51.2% (p=0.012, irradiation vs. control) respectively. Irradiation with 12 and 16 Gy protons, compared to the effects of the same doses of gamma rays, significantly reduced melanoma cell growth (p=0.015 and p=0.028, protons vs. gamma rays, respectively). Estimated RBEs for growth inhibition of HTB63 cells ranged from 1.02 to 1.45. The electrophoretical analyses of DNA samples and flow cytometric evaluation have shown a low percentage of apoptotic cells after both types of irradiation. The better inhibitory effect achieved by protons in contrast to gamma rays, can be explained considering specific physical properties of protons, especially taking into account the highly localized energy deposition (high LET).

  16. Genomic instability induced by 60Co γ ray radiation in normal human liver cells

    International Nuclear Information System (INIS)

    Gen Xiaohua; Guo Xianhua; Zuo Yahui; Wang Xiaoli; Wang Zhongwen

    2007-01-01

    Objective: To explore the genomic instability induced by 60 Co γ rays. Methods: The cloning efficiency and micronucleus efficiency of normal human liver cell irradiated by 60 Co γ rays were detected, and the method of single cell gel electrophoresis (SCGE) was carried out to measure DNA chains damage. The fast-growing cells were divided into different dose-groups and then irradiated by 60 Co γ rays. After 40 populations doubling, the progenies were secondly irradiated with 2 Gy 60 Co γ rays. Results: The cloning efficiency decreased with the increase of doses after the initial irradiation. After the survival cells were given second irradiation, both results of SCGE and micronucleus frequency showed that the second damage was correlated with the original irradiation doses. Conclusions: 60 Co γ rays can not only induce the immediate biological effects in liver cells, but also lead to the genomic instability in the descendants that leads to an enhanced frequency of genetic changes occurring among the progeny of the original irradiated cell. The expanding effect of second event helps to study the genomic instability. (authors)

  17. Effect of hypothermia on cell kinetics and response to hyperthermia and x rays

    International Nuclear Information System (INIS)

    van Rijn, J.; van den Berg, J.; Kipp, J.B.A.; Schamhart, D.H.J.; van Wijk, R.

    1985-01-01

    Hyperthermia is a potent radio enhancer. Studies using hypothermia in combination with irradiation have given confusing results due to lack of uniformity in experimental design. This report shows that hypothermia might have potential significance in the treatment of malignant cells with both thermo- and radiotherapy. Reuber H35 hepatoma cells, clone KRC-7 were used to study the effect of hypothermia on cell kinetics and subsequent response to hyperthermia and/or X rays. Cells were incubated at 8.5 0 C or between 25 and 37 0 C for 24 hr prior to hyperthermia or irradiation. Hypothermia caused sensitization to both hyperthermia and X rays. In contrast to the effect of hypothermia on either hyperthermia or X rays alone, thermal radiosensitization was decreased in hypothermically pretreated cells (24 hr at 25 0 C) compared to control cells (37 0 C). The expression of thermotolerance and the rate of development at 37 0 C after an initial heating at 42.5 0 C were not influenced after preincubation at 25 0 C for 24 hr. The expression of thermotolerance for heat or heat plus X rays during incubation at 41 0 C occurred in a significantly smaller number of cells after 24 hr preincubation at 25 0 C. The enhanced thermo- and radiosensitivity in hypothermically treated cells disappeared in approximately 6 hr after return to 37 0 C

  18. Deaths of cancer cells observed after X-Ray irradiation

    International Nuclear Information System (INIS)

    Kuwahara, Yoshikazu; Oikawa, Toshiyuki; Ochiai, Yasushi; Fukumoto, Motoi; Kurihara, Ai; Noma, Naoto; Shimura, Tsutomu; Fukumoto, Manabu; Ohkubo, Yasuhito

    2011-01-01

    Radiation induces cell death by apoptosis, autophagy (autophagic cell death, APCD), necrosis, which are respectively called type I, II, III programmed cell death, senescence, mitotic catastrophe, etc. This paper mainly describes details of authors' studies on APCD of clinically relevant radioresistant (CRR) HepG2-8960-R cells established from proliferating survivor even after repeated X-irradiation of >30 days x 2 Gy/day to the parent HepG2 cells. Autophagy forms autophagosome where many proteins are thoroughly degraded differing from proteasomal ubiquitin system, has been known essentially related to death and survival of injured cells under certain tissue conditions, and is distinguishable from other modes of cell death by morphological and cytochemical means. One of important authors' findings is as follows. APCD of CRR cells is normally seen in 20% and of the parent strain, 5%. When they are X-irradiated at 10 Gy, APCD of the latter is more (70%) than the former (40%), and no APCD is induced by 2 Gy x 5 days in the former in contrast to the latter. APCD by radiation is thus conceivably suppressed in CRR cells, suggesting that their radioresistance can be reversed by treatment to induce APCD. Autophagy is usually suppressed by mammalian target of rapamycin (mTOR), and when CRR cells are treated with rapamycin, they become radiosensitive to the comparable level to the parent HepG2. When HepG2 cells are treated with 3-methyladenine, an inhibitor of autophagy, or Beclin siRNA, they become radioresistant. For effectiveness of APCD induction and suppression on cancer therapy, results are contradictory in certain reports and autophagy should be a problem to be further elucidated from radiation biology aspect. (author)

  19. Apparent diffusion coefficient of renal parenchyma and color Doppler ultrasound of intrarenal arteries in patients with cirrhosis related renal dysfunction

    Directory of Open Access Journals (Sweden)

    Mohamed M Hefeda

    2014-12-01

    Conclusion: Liver cirrhosis, even in the presence of refractory ascites, did not affect the ADC value of renal parenchyma, however ADC value is affected in renal parenchyma of patients with hepato-renal syndrome. Duplex-Doppler ultrasound of intrarenal arteries enables the early detection of renal hemodynamic disturbances in patients with liver cirrhosis.

  20. Changes in the acinar distribution of some enzymes involved in carbohydrate metabolism in rat liver parenchyma after experimentally induced cholestasis

    NARCIS (Netherlands)

    van Noorden, C. J.; Frederiks, W. M.; Aronson, D. C.; Marx, F.; Bosch, K.; Jonges, G. N.; Vogels, I. M.; James, J.

    1987-01-01

    Extrahepatic cholestasis induced by ligation and transsection of the common bile duct caused a change in the parenchyma/stroma relationship in rat liver. Two weeks after ligation, the periportal zones of the parenchyma were progressively invaded by expanding bile ductules with surrounding connective

  1. Response of cultured normal human mammary epithelial cells to X rays

    International Nuclear Information System (INIS)

    Yang, T.C.; Stampfer, M.R.; Smith, H.S.

    1983-01-01

    The effect of X rays on the reproductive death of cultured normal human mammary epithelial cells was examined. Techniques were developed for isolating and culturing normal human mammary epithelial cells which provide sufficient cells at second passage for radiation studies, and an efficient clonogenic assay suitable for measuring radiation survival curves. It was found that the survival curves for epithelial cells from normal breast tissue were exponential and had D 0 values of about 109-148 rad for 225 kVp X rays. No consistent change in cell radiosensitivity with the age of donor was observed, and no sublethal damage repair in these cells could be detected with the split-dose technique

  2. Effects of UV, sunlight and X-ray radiation on quiescent human cells in culture

    International Nuclear Information System (INIS)

    Kantor, G.J.

    1986-01-01

    Nondividing human diploid fibroblasts (HDF) in culture have been used to study the effect on cell lethality of ultraviolet light, natural sunlight and X-rays. A lethal effect is defined as cellular degeneration, loss from the culture and inability to exclude vital strains. Far- and mid-UV have a readily observable lethal effect (cell loss), with DNA and DNA damage as the critical target and critical damage respectively. In part, natural sunlight kills cells by a similar mechanism but has an additional lethal effect at longer exposure times. This additional effect is expressed by the retention of the dead cells in culture, in contrast to the UV-induced promotion of cell degeneration and loss. Relatively large doses of X-rays that destroy proliferative capacity, have no detectable lethal effect on the maintenance of non-dividing cells. The biological response of nondividing HDF to radiations from different parts of the electromagnetic spectrum is dissimilar. (author)

  3. Progress in Cell Marking for Synchrotron X-ray Computed Tomography

    Science.gov (United States)

    Hall, Christopher; Sturm, Erica; Schultke, Elisabeth; Arfelli, Fulvia; Menk, Ralf-Hendrik; Astolfo, Alberto; Juurlink, Bernhard H. J.

    2010-07-01

    Recently there has been an increase in research activity into finding ways of marking cells in live animals for pre-clinical trials. Development of certain drugs and other therapies crucially depend on tracking particular cells or cell types in living systems. Therefore cell marking techniques are required which will enable longitudinal studies, where individuals can be examined several times over the course of a therapy or study. The benefits of being able to study both disease and therapy progression in individuals, rather than cohorts are clear. The need for high contrast 3-D imaging, without harming or altering the biological system requires a non-invasive yet penetrating imaging technique. The technique will also have to provide an appropriate spatial and contrast resolution. X-ray computed tomography offers rapid acquisition of 3-D images and is set to become one of the principal imaging techniques in this area. Work by our group over the last few years has shown that marking cells with gold nano-particles (GNP) is an effective means of visualising marked cells in-vivo using x-ray CT. Here we report the latest results from these studies. Synchrotron X-ray CT images of brain lesions in rats taken using the SYRMEP facility at the Elettra synchrotron in 2009 have been compared with histological examination of the tissues. Some deductions are drawn about the visibility of the gold loaded cells in both light microscopy and x-ray imaging.

  4. Yeast cell metabolism investigated by CO{_2} production and soft X-ray irradiation

    Science.gov (United States)

    Masini, A.; Batani, D.; Previdi, F.; Milani, M.; Pozzi, A.; Turcu, E.; Huntington, S.; Takeyasu, H.

    1999-01-01

    Results obtained using a new technique for studying cell metabolism are presented. The technique, consisting in CO2 production monitoring, has been applied to Saccharomyces cerevisiae yeast cells. Also the cells were irradiated using the soft X-ray laser-plasma source at Rutherford Appleton Laboratory with the aim of producing a damage of metabolic processes at the wall level, responsible for fermentation, without great interference with respiration, taking place in mitochondria, and DNA activity. The source was calibrated with PIN diodes and X-ray spectrometers and used Teflon stripes as target, emitting X-rays at about 0.9 keV, with a very low penetration in biological material. X-ray doses delivered to the different cell compartments were calculated following a Lambert-Bouguet-Beer law. Immediately after irradiation, the damage to metabolic activity was measured again by monitoring CO2 production. Results showed a general reduction in gas production by irradiated samples, together with non-linear and non-monotone response to dose. There was also evidence of oscillations in cell metabolic activity and of X-ray induced changes in oscillation frequency.

  5. Transmission electron microscopy, fluorescence microscopy, and confocal raman microscopic analysis of ultrastructural and compositional heterogeneity of Cornus alba L. wood cell wall.

    Science.gov (United States)

    Ma, Jianfeng; Ji, Zhe; Zhou, Xia; Zhang, Zhiheng; Xu, Feng

    2013-02-01

    Transmission electron microscopy (TEM), fluorescence microscopy, and confocal Raman microscopy can be used to characterize ultrastructural and compositional heterogeneity of plant cell walls. In this study, TEM observations revealed the ultrastructural characterization of Cornus alba L. fiber, vessel, axial parenchyma, ray parenchyma, and pit membrane between cells, notably with the ray parenchyma consisting of two well-defined layers. Fluorescence microscopy evidenced that cell corner middle lamella was more lignified than adjacent compound middle lamella and secondary wall with variation in lignification level from cell to cell. In situ Raman images showed that the inhomogeneity in cell wall components (cellulose and lignin) among different cells and within morphologically distinct cell wall layers. As the significant precursors of lignin biosynthesis, the pattern of coniferyl alcohol and aldehyde (joint abbreviation Lignin-CAA for both structures) distribution in fiber cell wall was also identified by Raman images, with higher concentration occurring in the fiber secondary wall where there was the highest cellulose concentration. Moreover, noteworthy was the observation that higher concentration of lignin and very minor amounts of cellulose were visualized in the pit membrane areas. These complementary microanalytical methods provide more accurate and complete information with regard to ultrastructural and compositional characterization of plant cell walls.

  6. In situ laser heating and radial synchrotron X-ray diffraction ina diamond anvil cell

    Energy Technology Data Exchange (ETDEWEB)

    Kunz, Martin; Caldwell, Wendel A.; Miyagi, Lowell; Wenk,Hans-Rudolf

    2007-06-29

    We report a first combination of diamond anvil cell radialx-ray diffraction with in situ laser heating. The laser-heating setup ofALS beamline 12.2.2 was modified to allow one-sided heating of a samplein a diamond anvil cell with an 80 W yttrium lithium fluoride laser whileprobing the sample with radial x-ray diffraction. The diamond anvil cellis placed with its compressional axis vertical, and perpendicular to thebeam. The laser beam is focused onto the sample from the top while thesample is probed with hard x-rays through an x-ray transparentboron-epoxy gasket. The temperature response of preferred orientation of(Fe,Mg)O is probed as a test experiment. Recrystallization was observedabove 1500 K, accompanied by a decrease in stress.

  7. Remote real time x-ray examination of fuel elements in a hot cell environment

    International Nuclear Information System (INIS)

    Yapuncich, F.L.

    1993-01-01

    This report discusses the Remote Real Time X-ray System which will allow for detailed examination of fuel elements. This task will be accomplished in a highly radioactive hot cell environment. Two remote handling systems win be utilized at the examination station. One handling system will transfer the fuel element to and from the shielded x-ray system. A second handling system will allow for vertical and rotational inspection of the fuel elements. The process win include removing a single nuclear fuel element from a element fabrication magazine(EFM), positioning the fuel element within the shielding envelope of the x-ray system and transferring the fuel element from the station manipulator to the x-ray system manipulator, performing the x-ray inspection, and then transferring the fuel element to either the element storage magazine(ESM) or a reject bin

  8. Apoptosis in thymocytes and lymphoma cells induced by neutrons and X-rays

    International Nuclear Information System (INIS)

    Ohyama, Harumi; Koike, Sachiko; Ando, Kouichi

    1993-01-01

    Apoptosis is a distinctive mode of programmed cell death with characteristic morphological and biochemical features. The cells undergoing apoptosis display shrinkage, chromatin condensation and internucleosomal breakage of DNA. The cell death is a process through which organisms get rid of unwanted cells. Thymocytes are highly radiosensitive, and undergo typical apoptosis within a few hours after the exposure to X-ray. Also extremely radiosensitive thymic lymphoma cells have been found. The effect of 30 MeV NIRS fast neutrons on the induction of apoptosis in thymocytes and thymoma cells was examined in comparison with that of X-ray. Although apoptotic cells increased gradually with time, the apoptotic process proceeded rapidly in individual cells after the onset. By the measurement of cell size distribution, the appearance of a distinct apoptotic cell peak was observed. In the case of neutron irradiation on SCA1 thymic lymphoma cells, the method for counting apoptotic cells based on chromatin condensation was developed. The cell volume reduction of thymocytes, the dose survival curves and the induction of apoptosis in SCA1 are reported. (K.I.)

  9. X-ray diffraction imaging of biological cells

    CERN Document Server

    Nakasako, Masayoshi

    2018-01-01

    In this book, the author describes the development of the experimental diffraction setup and structural analysis of non-crystalline particles from material science and biology. Recent advances in X-ray free electron laser (XFEL)-coherent X-ray diffraction imaging (CXDI) experiments allow for the structural analysis of non-crystalline particles to a resolution of 7 nm, and to a resolution of 20 nm for biological materials. Now XFEL-CXDI marks the dawn of a new era in structural analys of non-crystalline particles with dimensions larger than 100 nm, which was quite impossible in the 20th century. To conduct CXDI experiments in both synchrotron and XFEL facilities, the author has developed apparatuses, named KOTOBUKI-1 and TAKASAGO-6 for cryogenic diffraction experiments on frozen-hydrated non-crystalline particles at around 66 K. At the synchrotron facility, cryogenic diffraction experiments dramatically reduce radiation damage of specimen particles and allow tomography CXDI experiments. In addition, in XFEL ex...

  10. Radiation-Induced Bystander Effects in A549 Cells Exposed to 6 MV X-rays.

    Science.gov (United States)

    Yang, Shuning; Xu, Jing; Shao, Weixian; Geng, Chong; Li, Jia; Guo, Feng; Miao, Hui; Shen, Wenbin; Ye, Tao; Liu, Yazhou; Xu, Haiting; Zhang, Xuguang

    2015-07-01

    The aim of the study is to explore the bystander effects in A549 cells that have been exposed to 6MV X-ray. Control group, irradiated group, irradiated conditioned medium (ICM)-received group, and fresh medium group were designed in this study. A549 cells in the logarithmic growth phase were irradiated with 6MV X-ray at 0, 0.5, 1, 1.5, and 2. In ICM-received group, post-irradiation A549 cells were cultured for 3 h and were transferred into non-irradiated A549 cells for further cultivation. Clone forming test was applied to detect the survival fraction of cells. Annexin V-FITC/PI double-staining assay was used to detect the apoptosis of A549 cells 24, 48, 72, and 96 h after 2-Gy 6MV X-ray irradiation, and the curves of apoptosis were drawn. The changes in the cell cycles 4, 48, 72, and 96 h after 2-Gy 6MV X-ray irradiation were detected using PI staining flow cytometry. With the increase of irradiation dose, the survival fraction of A549 cells after the application of 0.5 Gy irradiation was decreasing continuously. In comparison to the control group, the apoptosis rate of the ICM-received group was increased in a time-dependent pattern, with the highest apoptosis rate observed at 72 h (p X-ray irradiation can induce bystander effect on A549 cells, which reaches a peak at 72 h.

  11. X-ray microbeam stand-alone facility for cultured cells irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bożek, Sebastian, E-mail: sebastian.bozek@yahoo.com [Jagiellonian University Medical College, Department of Pharmaceutical Biophysics, Krakow (Poland); Bielecki, Jakub; Wiecheć, Anna; Lekki, Janusz; Stachura, Zbigniew; Pogoda, Katarzyna; Lipiec, Ewelina; Tkocz, Konrad; Kwiatek, Wojciech M. [Institute of Nuclear Physics Polish Academy of Sciences, PL-31342 Krakow (Poland)

    2017-03-01

    Highlights: • An X-ray microbeam line for irradiation of living cultured cells was constructed. • A step by step explanation of working principles with engineering details, procedures and calculations is presented. • A model of beam and cell interaction is presented. • A method of uniform irradiation of living cells with an exact dose per a cell is presented. • Results of preliminary experiments are presented. - Abstract: The article describes an X-ray microbeam standalone facility dedicated for irradiation of living cultured cells. The article can serve as an advice for such facilities construction, as it begins from engineering details, through mathematical modeling and experimental procedures, ending up with preliminary experimental results and conclusions. The presented system consists of an open type X-ray tube with microfocusing down to about 2 μm, an X-ray focusing system with optical elements arranged in the nested Kirckpatrick-Baez (or Montel) geometry, a sample stand and an optical microscope with a scientific digital CCD camera. For the beam visualisation an X-ray sensitive CCD camera and a spectral detector are used, as well as a scintillator screen combined with the microscope. A method of precise one by one irradiation of previously chosen cells is presented, as well as a fast method of uniform irradiation of a chosen sample area. Mathematical models of beam and cell with calculations of kerma and dose are presented. The experiments on dose-effect relationship, kinetics of DNA double strand breaks repair, as well as micronuclei observation were performed on PC-3 (Prostate Cancer) cultured cells. The cells were seeded and irradiated on Mylar foil, which covered a hole drilled in the Petri dish. DNA lesions were visualised with γ-H2AX marker combined with Alexa Fluor 488 fluorescent dye.

  12. In situ X-ray studies of film cathodes for solid oxide fuel cells

    International Nuclear Information System (INIS)

    Fuoss, Paul; Chang, Kee-Chul; You, Hoydoo

    2013-01-01

    Highlights: •Synchrotron X-rays are used to study in operando the structural and chemical changes of LSM and LSCF film cathodes during half-cell operations. •A-site and B-site cations actively segregate or desegregate on the changes of temperature, pO 2 , and electrochemical potential. •Chemical lattice expansions show that oxygen-cathode interface is the primary source of rate-limiting processes. •The surface and subsurface of the LSM and LSCF films have different oxidation-states due to vacancy concentration changes. •Liquid-phase infiltration and coarsening processes of cathode materials into porous YSZ electrolyte backbone were monitored by USAXS. -- Abstract: Synchrotron-based X-ray techniques have been used to study in situ the structural and chemical changes of film cathodes during half-cell operations. The X-ray techniques used include X-ray reflectivity (XR), total-reflection X-ray fluorescence (TXRF), high-resolution diffraction (HRD), ultra-small angle X-ray scattering (USAXS). The epitaxial thin film model cathodes for XR, TXRF, and HRD measurements are made by pulse laser deposition and porous film cathodes for USAX measurements are made by screen printing technique. The experimental results reviewed here include A-site and B-site segregations, lattice expansion, oxidation-state changes during cell operations and liquid-phase infiltration and coarsening of cathode to electrolyte backbone

  13. Imaging mammalian cells with soft x rays: The importance of specimen preparation

    International Nuclear Information System (INIS)

    Brown, J.T.; Meyer-Ilse, W.

    1997-01-01

    Studies of mammalian cell structure and spatial organization are a very prominent part of modern cell biology. The interest in them as well as their size make them very accommodating subject specimens for imaging with soft x-rays using the XM-1 transmission microscope built and operated by The Center for X-ray Optics on Beam Line 6.1 at the Advanced Light Source. The purpose of these experiments was to determine if the fixative protocols normally used in electron or visible light microscopy were adequate to allow imaging cells, either fibroblasts or neurons, with minimal visible radiation damage due to imaging with soft x-rays at 2.4 nm. Two cell types were selected. Fibroblasts are easily cultured but fragile cells which are commonly used as models for the detailed study of cell physiology. Neurons are complex and sensitive cells which are difficult to prepare and to culture for study in isolation from their connections with surrounding cells. These cell types pose problems in their preparation for any microscopy. To improve the contrast and to prevent postmortem alteration of the chemistry and hence the structure of cells extracted from culture or from living organisms, fixation and staining techniques are employed in electron and visible light microscopy. It has been accepted by biologists for years that these treatments create artifacts and false structure. The authors have begun to develop protocols for specimens of each of these two cell types for soft x-ray microscopy which will preserve them in as near normal state as possible using minimal fixation, and make it possible to image them in either a hydrated or dried state free of secondary addition of stains or other labels

  14. Imaging mammalian cells with soft x rays: The importance of specimen preparation

    Energy Technology Data Exchange (ETDEWEB)

    Brown, J.T.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Studies of mammalian cell structure and spatial organization are a very prominent part of modern cell biology. The interest in them as well as their size make them very accommodating subject specimens for imaging with soft x-rays using the XM-1 transmission microscope built and operated by The Center for X-ray Optics on Beam Line 6.1 at the Advanced Light Source. The purpose of these experiments was to determine if the fixative protocols normally used in electron or visible light microscopy were adequate to allow imaging cells, either fibroblasts or neurons, with minimal visible radiation damage due to imaging with soft x-rays at 2.4 nm. Two cell types were selected. Fibroblasts are easily cultured but fragile cells which are commonly used as models for the detailed study of cell physiology. Neurons are complex and sensitive cells which are difficult to prepare and to culture for study in isolation from their connections with surrounding cells. These cell types pose problems in their preparation for any microscopy. To improve the contrast and to prevent postmortem alteration of the chemistry and hence the structure of cells extracted from culture or from living organisms, fixation and staining techniques are employed in electron and visible light microscopy. It has been accepted by biologists for years that these treatments create artifacts and false structure. The authors have begun to develop protocols for specimens of each of these two cell types for soft x-ray microscopy which will preserve them in as near normal state as possible using minimal fixation, and make it possible to image them in either a hydrated or dried state free of secondary addition of stains or other labels.

  15. Effects of X-ray irradiation combined with hyperthermia on human bone marrow cells

    International Nuclear Information System (INIS)

    Xie Huaijiang; Niu Rongjiu; Liu Xiaodong; Liu Huanqin

    1996-01-01

    The authors report on the effects of X-ray irradiation combined with hyperthermia on human bone marrow cells (BMC) in vitro. Observation was made on the morphology of treated cells under optic microscope and ultrastructural changes under electron microscope. The change was not obvious at first after treatment i,e, only the vacuolar degeneration was observed in a few cells under the EM. The survival of BMC alone after irradiation decreased with increase of the irradiation dose. The morphological changes included vacuolar degeneration of cells, swelling of mitochondria, and disintegration of nuclear membranes. The survival rate of BMC after irradiation combined with hyperthermia was significantly lower than that after treatment by either of them alone (P<0.01). The morphological changes were as follows: the cell structure was destroyed, the cell support system and cell organelles were destroyed, the cell membrane and nuclear membranes were destroyed, and the cell plasma and nuclear sap overflowed

  16. Interdependent action of nickel sulphate and X-rays on human lymphoblastoid leukeamic cells

    International Nuclear Information System (INIS)

    Bensimon, Jacques

    1977-01-01

    In a first experiment, cells were cultured in media supplemented by nickel sulphate, irradiated in same media and cultured in same media after irradiation. In a second experiment, cells were cultured during 18hrs. in media supplemented by nickel sulphate, and then cells were washed and cultured in normal media where they were irradiated. The nickel sulphate toxicity appears as a creasing function of the nickel sulphate concentration and the nickel sulphate action endurance. The nickel sulphate toxic effect is amplified by X-rays. This amplification is a time function that depends on the X-ray dose, nickel sulphate concentration and period of time from the outset of culture to the irradiation. The nickel sulphate toxic effect appears faster when nickel works after X-rays [fr

  17. Skin Reactions and Quality of Life after X-Ray Therapy of Basal Cell Carcinoma

    International Nuclear Information System (INIS)

    Skiveren, J.; Daugbjerg, H.; Wulf, H. C.; Mikkelsen, M. R.

    2012-01-01

    Background. Advanced basal cell carcinoma (BCC) is often treated by surgery or X-ray therapy. The consequences of X-ray therapy on the patients health-related quality-of-life (HRQOL) have so far not been described. Objectives. To quantify quality of life in BCC patients before and after X-ray therapy compared with matched healthy controls. Materials. Twenty-five patients (mean age 69) with BCC completed the Dermatology Life Quality Index (DLQI) before and two weeks and three months after X-ray therapy and their results were compared with the DLQI scores for 25 matched controls. Results. Compared to the healthy controls the patients' DLQI score was significantly higher before and 2 weeks after X-ray therapy ( ρ=0.005;ρ=0.000). The patients' DLQI score decreased significantly from baseline to three months after X-ray therapy (ρ=0.024), when it became similar to that of the healthy controls (ρ=0.819). Three months after X-ray therapy eight patients had no skin reactions, 11 had slight atrophy, pigmentation change, and/or some hair loss, four had patch atrophy, moderate telangiectasia, and/or total hair loss. Conclusions. BCC has a negative effect on patients' quality of life. The study shows that HRQOL normalises shortly after X-ray therapy, despite minor skin manifestations.

  18. 3D X-Ray Nanotomography of Cells Grown on Electrospun Scaffolds.

    Science.gov (United States)

    Bradley, Robert S; Robinson, Ian K; Yusuf, Mohammed

    2017-02-01

    Here, it is demonstrated that X-ray nanotomography with Zernike phase contrast can be used for 3D imaging of cells grown on electrospun polymer scaffolds. The scaffold fibers and cells are simultaneously imaged, enabling the influence of scaffold architecture on cell location and morphology to be studied. The high resolution enables subcellular details to be revealed. The X-ray imaging conditions were optimized to reduce scan times, making it feasible to scan multiple regions of interest in relatively large samples. An image processing procedure is presented which enables scaffold characteristics and cell location to be quantified. The procedure is demonstrated by comparing the ingrowth of cells after culture for 3 and 6 days. © 2016 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. X-ray studies on a two-dimensional diffusion limited system for cell growth

    International Nuclear Information System (INIS)

    Hlatky, L.R.; Alpen, E.L.

    1985-01-01

    X-ray studies were performed on cells grown in a new type of in vitro multicellular system, the ''sandwich'' system. This system is a two-dimensional array of cells, sandwiched between transparent slides which are impermeable to oxygen. The cell system is subject to self-created diffusion gradients of nutrients, metabolic products and, most importantly, oxygen. Sandwiches are analogous to living cross sections of multicellular spheroids or of poorly vascularized tumors. They contain a necrotic center, which the authors show to be due to diffusion limitations, an intermediate region which has a large fraction of quiescent cells and a cycling outer rim. One advantage sandwiches have over three-dimensional tumor models (sheproids) is that can control the amount of cell to cell contact and thereby separate effects due to oxygen or other gradients from effects due to contact. The authors present x-ray survival curves for sandwiches of various cell densities and compare them to x-ray survival curves done for spheroids and monolayers of the same cell line

  20. Contribution of computed tomography (CT) in affections of the lung parenchyma in HIV positive patients

    International Nuclear Information System (INIS)

    Neuwirth, J.; Stankova, M.; Spala, J.; Strof, J.

    1996-01-01

    CT findings in HIV positive patients with respiratory complaints were analyzed. The predominant morphological type of changes is a 'ground glass' increased density. Minimal changes of the lung parenchyma were recorded on high resolution computed tomography (HRCT) even in patients with a negative or doubtful finding on plain chest radiographs. Also the range of affections on HRCT scans was wider than on simple scans. The morphological changes on HRCT scans alone, however, are not an adequate basis for differentiation of various infectious agents in inflammatory changes of the lung parenchyma, and frequently mixed infections are involved. When at the same time clinical symptoms are considered, it frequently is possible to considerably reduce the number of possible pathogenic organisms and to start treatment. (author) 4 figs., 11 refs

  1. Solution spectroelectrochemical cell for in situ X-ray absorption fine structure

    International Nuclear Information System (INIS)

    Antonio, M.R.; Soderholm, L.

    1995-01-01

    A purpose-built spectroelectrochemical cell for in situ fluorescence XAFS (X-ray Absorption Fine Structure) measurements of bulk solution species during constant-potential electrolysis is described. The cell performance was demonstrated by the collection of europium L 3 -edge XANES (X-ray Absorption Near Edge Structure) throughout the course of electrolysis of an aqueous solution of EuCl 3 ·6H 2 O in 1 M H 2 SO 4 . The europium L 3 -edge resonances reported here for the Eu III and Eu II ions demonstrate that their 2p 3/2 → 5d electronic transition probabilities are not the same

  2. Soft x-ray-controlled dose deposition in yeast cells: techniques, model, and biological assessment

    Science.gov (United States)

    Milani, Marziale; Batani, Dimitri; Conti, Aldo; Masini, Alessandra; Costato, Michele; Pozzi, Achille; Turcu, I. C. Edmond

    1996-12-01

    A procedure is presented to release soft x-rays onto yeast cell membrane allegedly damaging the resident enzymatic processes connected with fermentation. The damage is expected to be restricted to regulating fermentation processes without interference with respiration. By this technique fermentation is followed leading to CO2 production, and respiration resulting in global pressure measurements. A solid state pressure sensor system has been developed linked to a data acquisition system. Yeast cells cultures have been investigated at different concentrations and with different nutrients. A non-monotone response in CO2 production as a function of the delivered x-ray dose is observed.

  3. Infarction and Laceration of Liver Parenchyma Caused by Wedged CO2 Venography Before TIPS Insertion

    International Nuclear Information System (INIS)

    Theuerkauf, Ingo; Strunk, Holger; Brensing, Karl August; Schild, Hans Heinz; Pfeifer, Ulrich

    2001-01-01

    We describe the fatal outcome of an elective TIPS procedure performed in a 43-year-old man with alcoholic cirrhosis. Wedged hepatic venography with CO 2 was the reason for infarction and laceration of liver parenchyma resulting in a subcapsular hematoma and subsequent intra-abdominal bleeding. This is the first report of this complication after the use of CO 2 in a cirrhotic patient

  4. First insights into the functional role of vasicentric tracheids and parenchyma in eucalyptus species with solitary vessels: do they contribute to xylem efficiency or safety?

    Science.gov (United States)

    Barotto, Antonio José; Fernandez, María Elena; Gyenge, Javier; Meyra, Ariel; Martinez-Meier, Alejandro; Monteoliva, Silvia

    2016-12-01

    The relationship between hydraulic specific conductivity (k s ) and vulnerability to cavitation (VC) with size and number of vessels has been studied in many angiosperms. However, few of the studies link other cell types (vasicentric tracheids (VT), fibre-tracheids, parenchyma) with these hydraulic functions. Eucalyptus is one of the most important genera in forestry worldwide. It exhibits a complex wood anatomy, with solitary vessels surrounded by VT and parenchyma, which could serve as a good model to investigate the functional role of the different cell types in xylem functioning. Wood anatomy (several traits of vessels, VT, fibres and parenchyma) in conjunction with maximum k s and VC was studied in adult trees of commercial species with medium-to-high wood density (Eucalyptus globulus Labill., Eucalyptus viminalis Labill. and Eucalyptus camaldulensis Dehnh.). Traits of cells accompanying vessels presented correlations with functional variables suggesting that they contribute to both increasing connectivity between adjacent vessels-and, therefore, to xylem conduction efficiency-and decreasing the probability of embolism propagation into the tissue, i.e., xylem safety. All three species presented moderate-to-high resistance to cavitation (mean P 50 values = -2.4 to -4.2 MPa) with no general trade-off between efficiency and safety at the interspecific level. The results in these species do not support some well-established hypotheses of the functional meaning of wood anatomy. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. MRI findings of cerebral parenchyma along a ventricular catheter under various intracranial conditions

    International Nuclear Information System (INIS)

    Yamamoto, Yoshisuke; Hoshino, Tamotsu; Suzuki, Hidenori

    1993-01-01

    We have experienced 4 cases of cerebral parenchymas in which high intensity was sustained by MRI T 2 WI, though a low density disappeared in CT, among the cases in which an expansion of the low density was observed in the cerebral parenchyma along a ventricular catheter by a CT scan after ventricular drainage and a shunt operation designed to combat increased intracranial pressure due to meningitis and a brain tumor. The cases were classified on the basis of morbidity into 1 case of cryptococcus meningitis, 1 case complicated by cerebellar hemorrhage and meningitis, and two cases of acute increased intracranial pressue due to a thalamic tumor and cerebellar astrocytoma. If a ventricular catheter or drainage tube is inserted, cerebral fluid penetrates into the cerebral parenchyma to cause a change in the tissue which can be explained, on the basis of CT findings, as a reversible change. However, this histological change is not always reversible according to our present MRI finding; rather, it becomes strong if the results of an inflammation such as meningitis are added to the cerebral fluid; in such a case, the reversibility is considered to disappear completely. (author)

  6. Radioindication of hemodynamics and functional state of parenchyma of the kidneys in stenosis of renal arteries

    International Nuclear Information System (INIS)

    Efimov, O.N.; Gabuniya, R.I.; Kamynin, Yu.F.; Matveenko, E.G.; Buyuklyan, A.N.; Skoropad, L.S.; Syzgantseva, L.M.

    1978-01-01

    Hemodynamics and functional state of parenchyma of the kidney were studied in 39 patients with stenosis of the renal arteries by means of pertechnetate 99 Tc, hippuran 131 I and chlormerodrine 197 Hg. In patients with vasorenal hypertension the following changes in the stenosed kidney were revealed: a significant decrease in the renal blood flow, renal fraction, volume of maximal saturation, specific blood flow, systolic renal index; elevation of the intrarenal vascular resistance; and impairment of the functional state of the renal parenchyma. It was established that there was a direct dependence between the renal blood flow and the volume of maximal saturation and a reverse dependence between the renal blood flow and intrarenal vascular resistance. Hemodynamic changes in the stenosed kidney played an important role and led at first to a bias in renographic indices and then - to a decrease in accumulation of chlormerodrine 197 Hg in the kidneys. It was noted that changes in the functional state of the renal parenchyma tended to be dependent upon the level of the renal blood flow, and indices of the renal blood flow - upon the values of arterial pressure. From diagnostic point of view, methods of radioiangiography, as compared with renography and scintigraphy, were found to be the most informative

  7. Molecular interactions of the combined effects of bleomycin and x-rays on mammalian cell survival

    International Nuclear Information System (INIS)

    Byfield, J.E.; Lee, Y.C.; Tu, L.; Kulhanian, F.

    1976-01-01

    The interactions between bleomycin and x-ray damage and repair have been examined in rat and human tumor cells. Bleomycin itself induces extensive DNA single-strand breaks but does not appear to inhibit the repair of x-ray-induced DNA single-strand breaks. Quantitative analysis of these interactions is complicated by the retention of active bleomycin within cells that remains capable of further DNA degradation even under the conditions of alkaline sucrose gradient cell lysis. DNA double-strand breaks and/or disruptions of DNA-lipid complexes also occur following bleomycin exposure. X-ray-induced excision repair replication is only minimally influenced by even high concentrations of bleomycin. A small amount of excision repair is demonstrable in nonirradiated cells treated with high concentrations of bleomycin consistent with repair of bleomycin-induced nucleotide damage in cellular DNA by a ''cut and patch'' repair mechanism. Repair of bleomycin-induced DNA single-strand breaks also occurs. The data indicate that bleomycin and x-ray damage are quite similar both in their induction and repair, but that lesions occur and are repaired independently. The enzymatic mechanisms appear similar in the two cell types despite substantial differences in their sensitivity to bleomycin

  8. Proteomic analysis of effects by x-rays and heavy ion in HeLa cells.

    Science.gov (United States)

    Bing, Zhitong; Yang, Guanghui; Zhang, Yanan; Wang, Fengling; Ye, Caiyong; Sun, Jintu; Zhou, Guangming; Yang, Lei

    2014-06-01

    Carbon ion therapy may be better against cancer than the effects of a photon beam. To investigate a biological advantage of carbon ion beam over X-rays, the radioresistant cell line HeLa cells were used. Radiation-induced changes in the biological processes were investigated post-irradiation at 1 h by a clinically relevant radiation dose (2 Gy X-ray and 2 Gy carbon beam). The differential expression proteins were collected for analysing biological effects. The radioresistant cell line Hela cells were used. In our study, the stable isotope labelling with amino acids (SILAC) method coupled with 2D-LC-LTQ Orbitrap mass spectrometry was applied to identity and quantify the differentially expressed proteins after irradiation. The Western blotting experiment was used to validate the data. A total of 123 and 155 significantly changed proteins were evaluated with treatment of 2 Gy carbon and X-rays after radiation 1 h, respectively. These deregulated proteins were found to be mainly involved in several kinds of metabolism processes through Gene Ontology (GO) enrichment analysis. The two groups perform different response to different types of irradiation. The radioresistance of the cancer cells treated with 2 Gy X-rays irradiation may be largely due to glycolysis enhancement, while the greater killing effect of 2 Gy carbon may be due to unchanged glycolysis and decreased amino acid metabolism.

  9. Proteomic analysis of effects by x-rays and heavy ion in HeLa cells

    International Nuclear Information System (INIS)

    Bing, Zhitong; Yang, Guanghui; Zhang, Yanan; Wang, Fengling; Ye, Caiyong; Sun, Jintu; Zhou, Guangming; Yang, Lei

    2014-01-01

    Carbon ion therapy may be better against cancer than the effects of a photon beam. To investigate a biological advantage of carbon ion beam over X-rays, the radioresistant cell line HeLa cells were used. Radiation-induced changes in the biological processes were investigated post-irradiation at 1 h by a clinically relevant radiation dose (2 Gy X-ray and 2 Gy carbon beam). The differential expression proteins were collected for analysing biological effects. The radioresistant cell line Hela cells were used. In our study, the stable isotope labelling with amino acids (SILAC) method coupled with 2D-LC-LTQ Orbitrap mass spectrometry was applied to identity and quantify the differentially expressed proteins after irradiation. The Western blotting experiment was used to validate the data. A total of 123 and 155 significantly changed proteins were evaluated with treatment of 2 Gy carbon and X-rays after radiation 1 h, respectively. These deregulated proteins were found to be mainly involved in several kinds of metabolism processes through Gene Ontology (GO) enrichment analysis. The two groups perform different response to different types of irradiation. The radioresistance of the cancer cells treated with 2 Gy X-rays irradiation may be largely due to glycolysis enhancement, while the greater killing effect of 2 Gy carbon may be due to unchanged glycolysis and decreased amino acid metabolism

  10. The amount of parenchyma and living fibers affects storage of nonstructural carbohydrates in young stems and roots of temperate trees.

    Science.gov (United States)

    Plavcová, Lenka; Hoch, Günter; Morris, Hugh; Ghiasi, Sara; Jansen, Steven

    2016-04-01

    Concentrations of nonstructural carbohydrates (NSCs) are used as proxies for the net carbon balance of trees and as indicators of carbon starvation resulting from environmental stress. Woody organs are the largest NSC-storing compartments in forest ecosystems; therefore, it is essential to understand the factors that affect the size of this important storage pool. In wood, NSC are predominantly deposited in ray and axial parenchyma (RAP); however, direct links between nutrient storage and RAP anatomy have not yet been established. Here, we tested whether the NSC storage capacity of wood is influenced by the amount of RAP. We measured NSC concentrations and RAP fractions in root and stem sapwood of 12 temperate species sampled at the onset of winter dormancy and in stem sapwood of four tropical trees growing in an evergreen lowland rainforest. The patterns of starch distribution were visualized by staining with Lugol's solution. The concentration of NSCs in sapwood of temperate trees scales tightly with the amount of RAP and living fibers (LFs), with almost all RAP and LFs being densely packed with starch grains. In contrast, the tropical species had lower NSC concentrations despite their higher RAP and LFs fraction and had considerable interspecific differences in starch distribution. The differences in RAP and LFs abundance affect the ability of sapwood to store NSC in temperate trees, whereas a more diverse set of functions of RAP might be pronounced in species growing in a tropical environment with little seasonality. © 2016 Botanical Society of America.

  11. Effects of oxygen and misonidazole on cell transformation and cell killing in C3H 10T1/2 cells by X rays in vitro

    International Nuclear Information System (INIS)

    Borsa, J.; Sargent, M.D.; Einspenner, M.; Azzam, E.I.; Raaphorst, G.P.

    1984-01-01

    The effects of oxygen (air) and misonidazole on the transformation and killing of 10T1/2 cells by X rays were examined. The oxygen effect for the cell transformation end point was very similar to that for cell killing. Misonidazole enhanced both cell killing and cell transformation to a similar extent. The enhancement of both end points by misonidazole occurred only in the absence of oxygen during irradiation and was of lesser magnitude than that observed for oxygen. These results demonstrate that the radiation chemical processes leading to cell killing and cell transformation, respectively, are affected similarly by these two enhancers of radiation action. 22 references, 3 figures, 2 tables

  12. Fate of D3 mouse embryonic stem cells exposed to X-rays or carbon ions.

    Science.gov (United States)

    Luft, S; Pignalosa, D; Nasonova, E; Arrizabalaga, O; Helm, A; Durante, M; Ritter, S

    2014-01-15

    The risk of radiation exposure during embryonic development is still a major problem in radiotoxicology. In this study we investigated the response of the murine embryonic stem cell (mESC) line D3 to two radiation qualities: sparsely ionizing X-rays and densely ionizing carbon ions. We analyzed clonogenic cell survival, proliferation, induction of chromosome aberrations as well as the capability of cells to differentiate to beating cardiomyocytes up to 3 days after exposure. Our results show that, for all endpoints investigated, carbon ions are more effective than X-rays at the same radiation dose. Additionally, in long term studies (≥8 days post-irradiation) chromosomal damage and the pluripotency state were investigated. These studies reveal that pluripotency markers are present in the progeny of cells surviving the exposure to both radiation types. However, only in the progeny of X-ray exposed cells the aberration frequency was comparable to that of the control population, while the progeny of carbon ion irradiated cells harbored significantly more aberrations than the control, generally translocations. We conclude that cells surviving the radiation exposure maintain pluripotency but may carry stable chromosomal rearrangements after densely ionizing radiation. Copyright © 2014 Elsevier B.V. All rights reserved.

  13. Macrophage and tumor cell responses to repetitive pulsed X-ray radiation

    Science.gov (United States)

    Buldakov, M. A.; Tretyakova, M. S.; Ryabov, V. B.; Klimov, I. A.; Kutenkov, O. P.; Kzhyshkowska, J.; Bol'shakov, M. A.; Rostov, V. V.; Cherdyntseva, N. V.

    2017-05-01

    To study a response of tumor cells and macrophages to the repetitive pulsed low-dose X-ray radiation. Methods. Tumor growth and lung metastasis of mice with an injected Lewis lung carcinoma were analysed, using C57Bl6. Monocytes were isolated from a human blood, using CD14+ magnetic beads. IL6, IL1-betta, and TNF-alpha were determined by ELISA. For macrophage phenotyping, a confocal microscopy was applied. “Sinus-150” was used for the generation of pulsed X-ray radiation (the absorbed dose was below 0.1 Gy, the pulse repetition frequency was 10 pulse/sec). The irradiation of mice by 0.1 Gy pulsed X-rays significantly inhibited the growth of primary tumor and reduced the number of metastatic colonies in the lung. Furthermore, the changes in macrophage phenotype and cytokine secretion were observed after repetitive pulsed X-ray radiation. Conclusion. Macrophages and tumor cells had a different response to a low-dose pulsed X-ray radiation. An activation of the immune system through changes of a macrophage phenotype can result in a significant antitumor effect of the low-dose repetitive pulsed X-ray radiation.

  14. Effects of hyperthermia, x-ray irradiation and their combination on ascites tumor cells of mice

    International Nuclear Information System (INIS)

    Kaneko, Itsuo

    1982-01-01

    Fibrosarcoma ascites tumor cells (PB8) from NMRI mice were used to investigate cell loss by hyperthermia and/or x-ray irradiation. The tumor cells were labelled by an injection of 125 I-deoxyuridine to the abdominal cavity of the donors 2 days before the physical treatments. The labelled cells, transfered in test tubes, were heated at 44 0 C for 10-20 min and/or irradiated by x-ray at 250-1612 rad, and were transplanted in the recipient abdominal cavity as soon as possible after the treatments. The radioactivity of the tumor cells, as an indicator of cell loss, was measured with a gamma spectrometer. In the irradiated group, the ratio of cell loss increased in a dose-dependent manner, starting from the 4th day after the transplantation to the 9th day. In the heated group, the ratio of cell loss increased in proportion to the heating time, starting without delay after transplantation. In the combination group, the effect of the treatments was more marked than that by each single treatment. In the early stage of this group, cell loss was by heating and then, from the 4th day, the irradiation effect mostly dominated. It is concluded from the above results that cell loss by heating or irradiation is independent and that the effect of the combination is additive. (author)

  15. Analysis of Giant-nucleated Cell Formation Following X-ray and Proton Irradiations

    Science.gov (United States)

    Almahwasi, Ashraf Abdu

    Radiation-induced genetic instability has been observed in survivors of irradiated cancerous and normal cells in vitro and in vivo and has been determined in different forms, such as delayed cell death, chromosomal aberration or mutation. A well defined and characterized normal human-diploid AG1522 fibroblast cell line was used to study giant-nucleated cell (GCs) formation as the ultimate endpoint of this research. The average nuclear cross-sectional areas of the AG1522 cells were measured in mum2. The doubling time required by the AG1522 cells to divide was measured. The potential toxicity of the Hoechst dye at a working concentration on the live AG1522 cells was assessed. The yield of giant cells was determined at 7, 14 and 21 days after exposure to equivalent clinical doses of 0.2, 1 or 2 Gy of X-ray or proton irradiation. Significant differences were found to exist between X-ray or proton irradiation when compared with sham-irradiated control populations. The frequency of GCs induced by X-rays was also compared to those formed in proton irradiated cultures. The results confirm that 1 Gy X-rays are shown to induce higher rates of mitotically arrested GCs, increasing continually over time up to 21 days post-irradiation. The yield of GCs was significantly greater (10%) compared to those formed in proton populations (2%) 21 days postirradiation. The GCs can undergo a prolonged mitotic arrest that significantly increases the length of cell cycle. The arrest of GCs at the mitotic phase for longer periods of time might be indicative of a strategy for cell survival, as it increases the time available for DNA repair and enables an alternative route to division for the cells. However, the reduction in their formation 21 days after both types of radiation might favour GCs formation, ultimately contributing to carcinogenesis or cancer therapy resistance. The X-ray experiments revealed a dose-dependent increase in the GCs up to 14 days after irradiation. Although the proton

  16. Influence of caffeine on X-ray-induced killing and mutation in V79 cells

    International Nuclear Information System (INIS)

    Bhattacharjee, S.B.; Bhattacharyya, N.; Chatterjee, S.

    1987-01-01

    Effects produced by caffeine on X-irradiated Chinese hamster V79 cells depended on the growth conditions of the cells. For exponentially growing cells, nontoxic concentrations of caffeine decreased the shoulder width from the survival curve, but the slope remained unchanged. The yield of mutants under the same conditions also remained unaffected. In case of density-inhibited cells, delaying trypsinization for 24 h after X irradiation increased the survival and decreased the yield of mutants. The presence of caffeine during this incubation period inhibited such recovery and significantly increased the yield of X-ray-induced mutants

  17. Influence of caffeine on X-ray-induced killing and mutation in V79 cells

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharjee, S.B.; Bhattacharyya, N.; Chatterjee, S.

    1987-02-01

    Effects produced by caffeine on X-irradiated Chinese hamster V79 cells depended on the growth conditions of the cells. For exponentially growing cells, nontoxic concentrations of caffeine decreased the shoulder width from the survival curve, but the slope remained unchanged. The yield of mutants under the same conditions also remained unaffected. In case of density-inhibited cells, delaying trypsinization for 24 h after X irradiation increased the survival and decreased the yield of mutants. The presence of caffeine during this incubation period inhibited such recovery and significantly increased the yield of X-ray-induced mutants.

  18. Soft X-ray induced chemical modification of polysaccharides in vascular plant cell walls

    International Nuclear Information System (INIS)

    Cody, George D.; Brandes, Jay; Jacobsen, Chris; Wirick, Susan

    2009-01-01

    Scanning transmission X-ray microscopy and micro carbon X-ray Absorption Near Edge Spectroscopy (C-XANES) can provide quantitative information regarding the distribution of the biopolymers cellulose, hemicellulose, and lignin in vascular plant cell walls. In the case of angiosperms, flowering plants, C-XANES may also be able to distinguish variations in lignin monomer distributions throughout the cell wall. Polysaccharides are susceptible to soft X-ray irradiation induced chemical transformations that may complicate spectral analysis. The stability of a model polysaccharide, cellulose acetate, to variable doses of soft X-rays under conditions optimized for high quality C-XANES spectroscopy was investigated. The primary chemical effect of soft X-ray irradiation on cellulose acetate involves mass loss coincident with de-acetylation. A lesser amount of vinyl ketone formation also occurs. Reduction in irradiation dose via defocusing does enable high quality pristine spectra to be obtained. Radiation induced chemical modification studies of oak cell wall reveals that cellulose and hemicellulose are less labile to chemical modification than cellulose acetate. Strategies for obtaining pristine C-XANES spectra of polysaccharides are presented.

  19. Viscoelastic Model for Lung Parenchyma for Multi-Scale Modeling of Respiratory System, Phase II: Dodecahedral Micro-Model

    Energy Technology Data Exchange (ETDEWEB)

    Freed, Alan D.; Einstein, Daniel R.; Carson, James P.; Jacob, Rick E.

    2012-03-01

    In the first year of this contractual effort a hypo-elastic constitutive model was developed and shown to have great potential in modeling the elastic response of parenchyma. This model resides at the macroscopic level of the continuum. In this, the second year of our support, an isotropic dodecahedron is employed as an alveolar model. This is a microscopic model for parenchyma. A hopeful outcome is that the linkage between these two scales of modeling will be a source of insight and inspiration that will aid us in the final year's activity: creating a viscoelastic model for parenchyma.

  20. Electrochemical cell for in situ x-ray diffraction under ultrapure conditions

    DEFF Research Database (Denmark)

    Koop, T.; Schindler, W.; Kazimirov, A.

    1998-01-01

    within a few seconds. The oxygen level in the electrolyte is reduced by continuous N(2) flow to less than 0.2% compared to that of a fresh electrolyte. This can be done while rotating the cell by 360 degrees about the surface normal. The electrode potential is accurately measured at the position......An electrochemical cell has been developed for in situ x-ray diffraction from a working electrode under clean conditions equivalent to ultrahigh vacuum conditions of 5 x 10(-10) mbar. The substrate crystals can be prepared ex situ and transferred into the cell under protection of ultrapure water...... of the crystal using a Luggin capillary and a standard reference electrode. We demonstrate the performance of our cell by in situ synchrotron x-ray diffraction measurements on ultrathin Co layers electrodeposited on Cu(001) in an aqueous H(2)SO(4)/CoSO(4) solution. (C) 1998 American Institute of Physics....

  1. X-ray dense cellular inclusions in the cells of the green alga Chlamydomonas reinhardtii as seen by soft-x-ray microscopy

    International Nuclear Information System (INIS)

    Stead, A.D.; Ford, T.W.; Page, A.M.; Brown, J.T.; Meyer-Ilse, W.

    1997-01-01

    Soft x-rays, having a greater ability to penetrate biological material than electrons, have the potential for producing images of intact, living cells. In addition, by using the so-called open-quotes water windowclose quotes area of the soft x-ray spectrum, a degree of natural contrast is introduced into the image due to differential absorption of the wavelengths by compounds with a high carbon content compared to those with a greater oxygen content. The variation in carbon concentration throughout a cell therefore generates an image which is dependent upon the carbon density within the specimen. Using soft x-ray contact microscopy the authors have previously examined the green alga Chlamydomonas reinhardtii, and the most prominent feature of the cells are the numerous x-ray absorbing spheres, But they were not seen by conventional transmission electron microscopy. Similar structures have also been reported by the Goettingen group using their cryo transmission x-ray microscope at BESSY. Despite the fact that these spheres appear to occupy up to 20% or more of the cell volume when seen by x-ray microscopy, they are not visible by transmission electron microscopy. Given the difficulties and criticisms associated with soft x-ray contact microscopy, the present study was aimed at confirming the existence of these cellular inclusions and learning more of their possible chemical composition

  2. X-ray dense cellular inclusions in the cells of the green alga Chlamydomonas reinhardtii as seen by soft-x-ray microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Stead, A.D.; Ford, T.W.; Page, A.M. [Univ. of London (United Kingdom); Brown, J.T.; Meyer-Ilse, W. [Ernest Orlando Lawrence Berkeley National Lab., CA (United States)

    1997-04-01

    Soft x-rays, having a greater ability to penetrate biological material than electrons, have the potential for producing images of intact, living cells. In addition, by using the so-called {open_quotes}water window{close_quotes} area of the soft x-ray spectrum, a degree of natural contrast is introduced into the image due to differential absorption of the wavelengths by compounds with a high carbon content compared to those with a greater oxygen content. The variation in carbon concentration throughout a cell therefore generates an image which is dependent upon the carbon density within the specimen. Using soft x-ray contact microscopy the authors have previously examined the green alga Chlamydomonas reinhardtii, and the most prominent feature of the cells are the numerous x-ray absorbing spheres, But they were not seen by conventional transmission electron microscopy. Similar structures have also been reported by the Goettingen group using their cryo transmission x-ray microscope at BESSY. Despite the fact that these spheres appear to occupy up to 20% or more of the cell volume when seen by x-ray microscopy, they are not visible by transmission electron microscopy. Given the difficulties and criticisms associated with soft x-ray contact microscopy, the present study was aimed at confirming the existence of these cellular inclusions and learning more of their possible chemical composition.

  3. Clinically relevant radioresistant cells efficiently repair DNA double-strand breaks induced by X-rays

    International Nuclear Information System (INIS)

    Kuwahara, Yoshikazu; Baba, Taisuke; Nakagawa, Hironobu; Shimura, Tsutomu; Yamamoto, Yoichiro; Fukumoto, Manabu; Li Li; Ohkubo, Yasuhito

    2009-01-01

    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 5-8 weeks. To understand the characteristics of radioresistant cells and to develop more effective radiotherapy, we established a novel radioresistant cell line, HepG2-8960-R with clinical relevance from parental HepG2 cells by long-term fractionated exposure to 2 Gy of X-rays. HepG2-8960-R cells continued to proliferate with daily exposure to 2 Gy X-rays for more than 30 days, while all parental HepG2 cells ceased. After exposure to fractionated 2 Gy X-rays, induction frequencies of micronuclei and remaining foci of γ-H2AX in HepG2-8960-R were less than those in HepG2. Flow cytometric analysis revealed that the proportion of cells in S- and G2/M-phase of the cell cycle was higher in HepG2-8960-R than in HepG2. These suggest that the response of clinically relevant radioresistant (CRR) cells to fractionated radiation is not merely an accumulated response to each fractionated radiation. This is the first report on the establishment of a CRR cell line from an isogenic parental cell line. (author)

  4. Molecular and biochemical analyses of spontaneous and X-ray-induced mutants in human lymphoblastoid cells

    Energy Technology Data Exchange (ETDEWEB)

    Liber, H L; Call, K M; Little, J B

    1987-05-01

    The authors have isolated a series of 14 spontaneously arising and 28 X-ray-induced mutants at the hypoxanthine-guanine phosphoribosyltransferase (hgprt) locus in human lymphoblastoid cells. Among the spontaneous mutants, 5/14 (36%) had detectable alterations in their restriction fragment pattern after hybridization with a human cDNA probe for hgprt. Of the 10 remaining mutants, 4 had partial HGPRT enzyme activity, which suggested that they contained point mutations. Among the 28 mutants induced by 150 rad of X-rays, 15 (54%) had deletions of part or all of the hgprt gene. Of the remaining 13 (18% overall) 5 had partial HGPRT enzyme activity, which suggested that they contained point mutations. These data imply that in this human cell system, X-rays induce both point mutants which have residual enzyme activity as well as mutations involving relatively large deletions of DNA. 48 reference, 1 figure, 4 tables.

  5. Do Dental X-Rays Induce Genotoxicity and Cytotoxicity in Oral Mucosa Cells? A Critical Review.

    Science.gov (United States)

    Angelieri, Fernanda; Yujra, Veronica Quispe; Oshima, Celina Tizuko Fujiyama; Ribeiro, Daniel Araki

    2017-10-01

    Dental X-rays are widely used in clinical practice, since the technique is an important approach for diagnosing diseases in dental and periodontal tissues. However, it is widely known that radiation is capable of causing damage to cellular systems, such as genotoxicity or cytotoxicity. Thus, the aim of this review was to present a critical analysis regarding the studies published on genotoxicity and cytotoxicity induced by dental X-rays in oral mucosa cells. Such studies have revealed that some oral cell types are more sensitive than others following exposure to dental X-rays. Certainly, this review will contribute to a better understanding of this matter as well as to highlighting perspectives for further studies. Ultimately, such data will promote better safety for both patients and dental professionals. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  6. Sample cell for in-field X-ray diffraction experiments

    Directory of Open Access Journals (Sweden)

    Viktor Höglin

    2015-01-01

    Full Text Available A sample cell making it possible to perform synchrotron radiation X-ray powder diffraction experiments in a magnetic field of 0.35 T has been constructed. The device is an add-on to an existing sample cell and contains a strong permanent magnet of NdFeB-type. Experiments have shown that the setup is working satisfactory making it possible to perform in-field measurements.

  7. Lead induced modifications of the response to X-rays in human cells in culture

    International Nuclear Information System (INIS)

    Skreb, Y.; Habazin-Novak, V.

    1977-01-01

    The rate of 3 H-thymidine uptake by HeLa cells submitted to X-ray irradiation is reduced if the cells are treated with lead chloride. The inhibitory effects of the two agents were found additive. After irradiation no new incorporation appears while lead is present in the medium. If after four hours the medium containing lead is substituted by a fresh one, the 3 H-thymidine uptake is resumed after a short delay. (author)

  8. Calculation of absorbed dose of anchorage-dependent cells from internal beta-rays irradiation

    International Nuclear Information System (INIS)

    Chen Jianwei; Huang Gang; Li Shijun

    2001-01-01

    Objective: To elicit the formula of internal dosimetry in anchorage-dependent cells by beta-emitting radionuclides from uniformly distributed volume sources. Methods: By means of the definition of absorbed dose and the MIRD (Medical International Radiation Dose) scheme the formula of internal dosimetry was reasonably deduced. Firstly, studying the systems of suspension culture cells. Then, taking account of the speciality of the systems of the anchorage-dependent cells and the directions of irradiation, the absorbed dose of anchorage -dependent cells was calculated by the accumulated radioactivity, beta-ray energy, and the volume of the cultured systems. Results: The formula of internal dosimetry of suspension culture cells and anchorage-dependent cells were achieved. At the same time, the formula of internal dosimetry of suspension culture cells was compared with that of MIRD and was confirmed accurate. Conclusion: The formula of internal dosimetry is concise, reliable and accurate

  9. Induction of cell death in the testis of Heteracris littoralis by gamma rays

    International Nuclear Information System (INIS)

    Al-Taweel, A.A.; Shawkit, M.A.

    1983-01-01

    Cell killing by gamma rays was studied in Heteracris littoralis. Primary spermatocytes, which are encysted and have cytoplasmic connection, show unusual dose-response kinetics with no shoulder at low doses. Also, the spermatocytes do not die independently but in groups, usually with whole cysts degenerating synchronously. (author)

  10. X-ray microimaging of cisplatin distribution in ovarian cancer cells

    International Nuclear Information System (INIS)

    Kiyozuka, Yasuhiko; Tsubura, Airo; Takemoto, Kuniko; Kihara, Hiroshi; Yamamoto, Akitsugu; Guttmann, Peter

    2000-01-01

    X-ray microscopy has the possibility to be in use for elemental analysis of tissue and cells especially under physiological conditions with high lateral resolution. In X-ray microimaging cisdiamminedichloroplatinum II (cisplatin: CDDP), an anticancer agent, which has a platinum atom at its functional center gives sufficient contrast against organic material at sub-cellular level. We analyzed the enhance effect and intracellular distribution of CDDP in human ovarian cancer cells with the transmission X-ray microscope at BESSY, Berlin. Two human ovarian cancer cell lines (MN-1 and EC) were treated with 1 and 10 μg/ml of CDDP for 4 hours and compared with untreated cells X-ray images of CDDP-treated samples show clearly labeled nucleoli, periphery of the nucleus and mitochondria, in a concentration-dependent manner. CDDP binds to DNA molecules via the formation of intra- or-inter-strand cross-links. Higher contrasts at the periphery of nucleus and nucleoli suggest the distribution of tightly packed heterochromatin. In addition, results show the possibility that CDDP binds to mitochondrial DNA. Biological function of cisplatin is not only the inhibition of DNA replication but is suggested to disturb mitochondrial function and RNA synthesis in the nucleolus

  11. Resonant Soft X-ray Scattering of Cellulose Microstructure in Plant Primary Cell Walls

    Science.gov (United States)

    Ye, Dan; Kiemle, Sarah N.; Wang, Cheng; Cosgrove, Daniel J.; Gomez, Esther W.; Gomez, Enrique D.

    Cellulosic biomass is the most abundant raw material available for the production of renewable and sustainable biofuels. Breaking down cellulose is the rate-limiting step in economical biofuel production; therefore, a detailed understanding of the microscopic structure of plant cell walls is required to develop efficient biofuel conversion methods. Primary cell walls are key determinants of plant growth and mechanics. Their structure is complex and heterogeneous, making it difficult to elucidate how various components such as pectin, hemicellulose, and cellulose contribute to the overall structure. The electron density of these wall components is similar; such that conventional hard X-ray scattering does not generate enough contrast to resolve the different elements of the polysaccharide network. The chemical specificity of resonant soft X-ray scattering allows contrast to be generated based on differences in chemistry of the different polysaccharides. By varying incident X-ray energies, we have achieved increased scattering contrast between cellulose and other polysaccharides from primary cell walls of onions. By performing scattering at certain energies, features of the network structure of the cell wall are resolved. From the soft X-ray scattering results, we obtained the packing distance of cellulose microfibrils embedded in the polysaccharide network.

  12. Effects of x-ray irradiation on mast cells and mastocalcergy in the connective tissue

    Energy Technology Data Exchange (ETDEWEB)

    Song, H. Y.; Rhee, S. J.; Son, M. H.; Choi, K. C. [Chonbuk National University College of Medicine, Jeonju (Korea, Republic of)

    1982-09-15

    Experiments were performed to observe the influence of x-ray irradiation on mast cells and mastocalcergy in rats. Animals were irradiated single dose of x-ray. X-ray irradiation was applied to the whole body in doses either 100 rads or 150 rads (Cobalt-60 Teletherapy Unit). One day after irradiation the rats were injected lead acetate intravenously, followed by injection of compound 48/80 in the back subcutaneously. Animals were killed by decapitation at intervals, 1 hour, 5 hours, 1 day and 6 day after subcutaneous injection. Specimens of the abdominal and back skin were fixed in alcohol formol solution and stained with the following methods; H-E for observation of pathological changes of tissues, toluidine blue for demonstration of mast cells, von Kossa-azure A for demonstration of carbonate and phosphate, and chloranilic acid for demonstration of calcium. The following conclusions were obtained. Calciphylatic wheals are large size in the control group, medium size in 100 rads irradiation group and small size in 150 rads irradiation group. In x-ray irradiation groups the number of mast cells decreases more in the 150 rads than in the 100 rads irradiation. In the 100 rads x-ray irradiation group, histochemical study of the injection sites showed that calcium impregnated to mast cell granules and connective tissue fibers in 1 days after subcutaneous injection. The morphogenesis of this calcinosis was the same in the rat of 5 hour after subcutaneous injection of the control group. Whereas, 1 day after subcutaneous injection in 150 rads x-ray irradiation group calcium deposited more slightly than other groups.

  13. Quantification of phosphorus in single cells using synchrotron X-ray fluorescence

    Energy Technology Data Exchange (ETDEWEB)

    Núñez-Milland, Daliángelis R. [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States); Baines, Stephen B. [Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY 11755 (United States); Vogt, Stefan [Experimental Facilities Division, Advanced Photon Source, Argonne National Laboratory, Argonne, IL (United States); Twining, Benjamin S., E-mail: btwining@bigelow.org [Department of Chemistry and Biochemistry, University of South Carolina, Columbia, SC 29208 (United States)

    2010-07-01

    Phosphorus abundance was quantified in individual phytoplankton cells by synchrotron X-ray fluorescence and compared with bulk spectrophotometric measurements to confirm accuracy of quantification. Figures of merit for P quantification on three different types of transmission electron microscopy grids are compared to assess possible interferences. Phosphorus is required for numerous cellular compounds and as a result can serve as a useful proxy for total cell biomass in studies of cell elemental composition. Single-cell analysis by synchrotron X-ray fluorescence (SXRF) enables quantitative and qualitative analyses of cell elemental composition with high elemental sensitivity. Element standards are required to convert measured X-ray fluorescence intensities into element concentrations, but few appropriate standards are available, particularly for the biologically important element P. Empirical P conversion factors derived from other elements contained in certified thin-film standards were used to quantify P in the model diatom Thalassiosira pseudonana, and the measured cell quotas were compared with those measured in bulk by spectrophotometry. The mean cellular P quotas quantified with SXRF for cells on Au, Ni and nylon grids using this approach were not significantly different from each other or from those measured spectrophotometrically. Inter-cell variability typical of cell populations was observed. Additionally, the grid substrates were compared for their suitability to P quantification based on the potential for spectral interferences with P. Nylon grids were found to have the lowest background concentrations and limits of detection for P, while background concentrations in Ni and Au grids were 1.8- and 6.3-fold higher. The advantages and disadvantages of each grid type for elemental analysis of individual phytoplankton cells are discussed.

  14. Gamma-ray imaging and holdup assays of 235-F PuFF cells 1 & 2

    Energy Technology Data Exchange (ETDEWEB)

    Aucott, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-12-20

    Savannah River National Laboratory (SRNL) Nuclear Measurements (L4120) was tasked with performing enhanced characterization of the holdup in the PuFF shielded cells. Assays were performed in accordance with L16.1-ADS-2460 using two high-resolution gamma-ray detectors. The first detector, an In Situ Object Counting System (ISOCS)-characterized detector, was used in conjunction with the ISOCS Geometry Composer software to quantify grams of holdup. The second detector, a Germanium Gamma-ray Imager (GeGI), was used to visualize the location and relative intensity of the holdup in the cells. Carts and collimators were specially designed to perform optimum assays of the cells. Thick, pencil-beam tungsten collimators were fabricated to allow for extremely precise targeting of items of interest inside the cells. Carts were designed with a wide range of motion to position and align the detectors. A total of 24 measurements were made, each typically 24 hours or longer to provide sufficient statistical precision. This report presents the results of the enhanced characterization for cells 1 and 2. The measured gram values agree very well with results from the 2014 study. In addition, images were created using both the 2014 data and the new GeGI data. The GeGI images of the cells walls reveal significant Pu-238 holdup on the surface of the walls in cells 1 and 2. Additionally, holdup is visible in the two pass-throughs from cell 1 to the wing cabinets. This report documents the final element (exterior measurements coupled with gamma-ray imaging and modeling) of the enhanced characterization of cells 1-5 (East Cell Line).

  15. Characterization of the adaptive response to ionizing radiation induced by low doses of X-rays to Vibrio cholerae cells

    International Nuclear Information System (INIS)

    Basak, Jayasri

    1996-01-01

    Pretreatment with sublethal doses of X-rays induced an adaptive response in Vibrio cholerae cells as indicated by their greater resistance to the subsequent challenging doses of X-irradiation. The adaptive response was maximum following a pre-exposure dose of 1.7 Gy X-rays and an optimum incubation period of 40 min at 37C. Pre-exposure to a sublethal dose of 1.7 Gy X-rays made the Vibrio cholerae cells 3.38-fold more resistant to the subsequent challenge by X-rays. Pretreatment with a sublethal dose of hydrogen peroxide offered a similar degree of protection to the bacterial cells against subsequent treatment with challenging doses of X-ray radiation. However, exposure of Vibrio cholerae cells to mild heat (42C for 10 min) before X-ray irradiation decreased their survival following X-irradiation

  16. Carbon ion beam is more effective to induce cell death in sphere-type A172 human glioblastoma cells compared with X-rays.

    Science.gov (United States)

    Takahashi, Momoko; Hirakawa, Hirokazu; Yajima, Hirohiko; Izumi-Nakajima, Nakako; Okayasu, Ryuichi; Fujimori, Akira

    2014-12-01

    To obtain human glioblastoma cells A172 expressing stem cell-related protein and comparison of radiosensitivity in these cells with X-rays and carbon beam. Human monolayer-type A172 glioblastoma cells were maintained in normal medium with 10% bovine serum. In order to obtain sphere-type A172 cells the medium was replaced with serum-free medium supplemented with growth factors. Both types of A172 cells were irradiated with either X-rays or carbon ion beams and their radiosensitivity was evaluated. Serum-free medium induced expression of stem cell-related proteins in A172 cells along with the neurosphere-like appearance. These sphere-type cells were found resistant to both X-rays and carbon ion beams. Phosphorylation of histone H2A family member X persisted for a longer period in the cells exposed to carbon ion beams than in those exposed to X-rays and it disappeared quicker in the sphere type than in the monolayer type. Relative radioresistance of the sphere type cells was smaller for carbon ion beams than for X-rays. We demonstrated that glioblastoma A172 cells with induced stem cell-related proteins turned resistant to irradiation. Accelerated heavy ion particles may have advantage over X-rays in overcoming the tumor resistance due to cell stemness.

  17. Comparing renal function preservation after laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy for clinical T1a renal tumor: using a 3D parenchyma measurement system.

    Science.gov (United States)

    Zhu, Liangsong; Wu, Guangyu; Huang, Jiwei; Wang, Jianfeng; Zhang, Ruiyun; Kong, Wen; Xue, Wei; Huang, Yiran; Chen, Yonghui; Zhang, Jin

    2017-05-01

    To compare the renal function preservation between laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy. Data were analyzed from 246 patients who underwent laparoscopic radio frequency ablation assisted tumor enucleation and laparoscopic partial nephrectomy for solitary cT1a renal cell carcinoma from January 2013 to July 2015. To reduce the intergroup difference, we used a 1:1 propensity matching analysis. The functional renal parenchyma volume preservation were measured preoperative and 12 months after surgery. The total renal function recovery and spilt GFR was compared. Multivariable logistic analysis was used for predictive factors for renal function decline. After 1:1 propensity matching, each group including 100 patients. Patients in the laparoscopic radio frequency ablation assisted tumor enucleation had a smaller decrease in estimate glomerular filtration rate at 1 day (-7.88 vs -20.01%, p renal parenchyma volume preservation (89.19 vs 84.27%, p renal parenchyma volume preservation, warm ischemia time and baseline renal function were the important independent factors in determining long-term functional recovery. The laparoscopic radio frequency ablation assisted tumor enucleation technology has unique advantage and potential in preserving renal parenchyma without ischemia damage compared to conventional laparoscopic partial nephrectomy, and had a better outcome, thus we recommend this technique in selected T1a patients.

  18. Killing effect of peripheral blood mononuclear cells irradiated by γ ray on human gastric cancer MKN-28 cell

    International Nuclear Information System (INIS)

    Wu Daocheng; Zhang Xianqing; Mu Shijie; Liu Zhongxiang; Xia Aijun; Huang Xiaofeng; An Qunxing

    2007-01-01

    Objective: To observe the killing effect of peripheral blood mononuclear cells (PBMCs) irradiated by γ ray on cultured human gastric cancer cell line MKN-28. Methods: The experiment were divided into MKN-28 tumor cell control group, PBMCs groups and MKN-28 cells with irradiated or non-irradiated PBMCs co-culture groups. Radidation dosage were from 0.5 to 3 Gy, acridine orange/ethidium bromide (AO/EB) staining were used to observe the kill effect of PBMCs on tumor cells in different period. Results: After culture for 144h, the dead cells of several dosage irradiated PBMCs are much more than those of non-irradiated PBMCs group. At 240 hours of culture, the alive PBMCs deareses in number in both irradiated and non-irradiared groups, but decreases in radiated groups are more obvious. After culture for 72 h in the co-cultured groups, the difference is not evident among all radiation dosage groups. After 96-240 h of co-culture, the killing effect of 0.5-2Gy irradiated PBMCs on tumor cells is very strong, especially in 1Gy group, but the killing effect of PBMCs irradiated by 2.5-3Gy on tumor cells were weaker than that of 0.5-2Gy irradiated groups. At 240 hours co-cultured groups irradiated by 2.5-3Gy, tumor cells still survive and proliferate. Conclusion: Gamma ray irradiation have killing effect to some PBMCs. The cytocidal effect of PBMCs irradiated by 0.5-2Gy on tumor cells were increased. Chemotaxis and cytocidal effect of tumor cells to postirradiated PBMCs were also found. The killing effect of PBMCs irradiated by 2.5 and 3 Gy on tumor cells were restrained. (authors)

  19. Selection of variants with high levels of biotin from cultured green Lavandula vera cells irradiated with gamma rays

    International Nuclear Information System (INIS)

    Watanabe, K.; Yamada, Y.

    1982-01-01

    Cultured green Lavandula vera cells were irradiated with various dosages of gamma rays which increased the variation in the amount of free biotin produced by the cell clones. Variant sublines containing much more free biotin than the original line were obtained by repeated selection. The effectiveness of gamma rays for the induction of the variant sublines is described

  20. DNA microarray analyses reveal a post-irradiation differential time-dependent gene expression profile in yeast cells exposed to X-rays and gamma-rays.

    Science.gov (United States)

    Kimura, Shinzo; Ishidou, Emi; Kurita, Sakiko; Suzuki, Yoshiteru; Shibato, Junko; Rakwal, Randeep; Iwahashi, Hitoshi

    2006-07-21

    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. Moreover, few studies have focused on large-scale identification of cellular responses to IR, and to this end, we describe here an initial study on the transcriptional responses of the unicellular genome model, yeast (Saccharomyces cerevisiae strain S288C), by cDNA microarray. The effect of two different IR, X-rays, and gamma (gamma)-rays, was investigated by irradiating the yeast cells cultured in YPD medium with 50 Gy doses of X- and gamma-rays, followed by resuspension of the cells in YPD for time-course experiments. The samples were collected for microarray analysis at 20, 40, and 80 min after irradiation. Microarray analysis revealed a time-course transcriptional profile of changed gene expressions. Up-regulated genes belonged to the functional categories mainly related to cell cycle and DNA processing, cell rescue defense and virulence, protein and cell fate, and metabolism (X- and gamma-rays). Similarly, for X- and gamma-rays, the down-regulated genes belonged to mostly transcription and protein synthesis, cell cycle and DNA processing, control of cellular organization, cell fate, and C-compound and carbohydrate metabolism categories, respectively. This study provides for the first time a snapshot of the genome-wide mRNA expression profiles in X- and gamma-ray post-irradiated yeast cells and comparatively interprets/discusses the changed gene functional categories as effects of these two radiations vis-à-vis their energy levels.

  1. Gamma-ray mutagenesis of cultured mammalian cells in vitro and in vivo

    International Nuclear Information System (INIS)

    Suzuki, Norio; Okada, Shigefumi

    1977-01-01

    The in vitro assay system used to study the reversion of L5178Y-Ala32 cells from an alanine requiring state to a non-requiring state, has been modified in order to be of use in selected in vivo systems. Gamma-ray induced mutations were compared between cells cultured in vitro and those grown in vivo in the intraperitoneal cavity of mice. The expression time was chosen to be 2 days for cells grown in vitro and 5 days for those grown in vivo. The dose-response curve can be described as cumulative for cells grown in vitro and linear for those grown in vivo. A doserate effect was observed in both systems. The cells grown in vivo were less sensitive to γ-rays with respect to both mutation rate per rad and cell killing as compared to cells grown in vitro. The delayed expression and reduced sensitivity of cells in vivo with respect to induced mutation may be due to factors such as hypoxia and/or reduced availability of essential nutrients. Sensitization in vitro by BUdR was detectable at a concentration as low as 10 -6 M, using an exposure time of 15 h. Under these conditions, BUdR alone did not induce any observable mutations

  2. Assessment of selected B cells populations in the workers of X-ray departments

    Directory of Open Access Journals (Sweden)

    Piotr Kłuciński

    2014-08-01

    Full Text Available Objectives: Workers of X-ray departments are occupationally exposed to long-term low levels of ionizing radiation (LLIR, which may affect their humoral immunity. The aim of the study was to assess the influence of LLIR on the number and proportion of B cells (CD19+, B1 cells (CD5+CD19+ and memory B cells (CD27+CD19+ in peripheral blood of such workers. Materials and Methods: In the study group of 47 X-ray departments workers and the control group consisting of 38 persons, the number and percentage of CD19+, CD5+CD19+, CD27+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were assessed using flow cytometry. Additionally, the study group was divided into 2 groups by the length of employment below and over 15 years and analysis adjusted for age and smoking habit was performed. Results: The total number of CD19+ cells showed significant increase in the group of workers in comparison with the persons from the control group, whereas the percentage of CD5+CD19+ cells as well as CD27+CD19+/CD19+ and CD5+CD19+/CD19+ cell ratios were lower. Percentage, number of CD5+CD19+ cells and CD5+CD19+/CD19+ cell ratio were significantly lower in the workers with length of employment longer than 15 years in comparison with those employed below 15 years. Moreover, we found positive associations between the number of CD19+ cells and employment as well as smoking habit, whereas the number of CD5+CD19+ cells was positively associated with cigarette smoking alone. Percentage of CD5+CD19+ cells as well as CD5+CD19+/CD19+ and CD27+CD19+/CD19+ cell ratios were negatively correlated with employment. Conclusions: The study suggests association between the suppressive influence of low level ionizing radiation on circulating in peripheral blood, especially of B1 cells as well as of memory B cells, in workers of X-ray units, which is adverse in relation to microbiological threat.

  3. Identification of differentially expressed genes associated with the enhancement of X-ray susceptibility by RITA in a hypopharyngeal squamous cell carcinoma cell line (FaDu

    Directory of Open Access Journals (Sweden)

    Luan Jinwei

    2016-06-01

    Full Text Available Next generation sequencing and bio-informatic analyses were conducted to investigate the mechanism of reactivation of p53 and induction of tumor cell apoptosis (RITA-enhancing X-ray susceptibility in FaDu cells.

  4. Genetic control of x-ray resistance in budding yeast cells

    International Nuclear Information System (INIS)

    Benathen, I.A.; Beam, C.A.

    1977-01-01

    Five x-ray-sensitive mutants were selected from 10,000 colonies arising from survivors of ultraviolet light. These were named XS5, XS6, XS7, XS8, and XS9. Mutant XS1 was donated by Nakai. These mutations affect the resistant budding cell survival component of the survival curve and, in diploids, the low-dose interdivisional cell shoulder. They are of two types: Class I, in which budding cells lack resistance; and Class II, in which budding cells show reduced resistance. When crossed with one another, they show a complex complementation pattern. Gene dosage effects are seen in XS1 heterozygotes, while budding but not between divisions. No direct correlation between radiation sensitivity, meiosis, and sporulation is observed; genes which influence radiation sensitivity do not affect meiotic recombination. A single mutation (XS1 or XS5) suppresses the shoulders of the survival curves of both budding haploid cells and diploid nonbudding cells

  5. The effect of caffeine on x-ray repair of radioresistant HeLa cells

    International Nuclear Information System (INIS)

    Kubo, Kihei; Koiwai, Soichiro; Morita, Kazuo

    1985-01-01

    The contribution of caffeine-modifiable repair process to the radiosensitivity of a radioresistant HeLa strain (RC-355) has been investigated in comparison with control HeLa strain (CC-24). Both the final slope and the shoulder of X-ray survival curve for log-phase cells were affected by caffeine posttreatment. When the treatment with 10 mM caffeine delayed, an increase in survival was observed with increasing interval between irradiation and the treatment. During first several hours of the repair interval, the steepness of the final slope of survival curve decreased rapidly, and rate of the decrease was found to be higher in RC-355 than in CC-24 cells. Longer time (24 hours or more) before the initiation of caffeine treatment was required for the complete recovery of the shoulder. When the cells were incubated in plateau-phase after irradiation, an appreciable increase in survival was observed in comparison with when plated immediately following X-ray. The increase was found to be greater for RC-355 than for CC-24. The results suggest that the radioresistant RC-355 cells repaired more X-ray-induced PLD than CC-24 cells did. (author)

  6. Application of X-ray microanalysis to the study of drug uptake in cell culture

    International Nuclear Information System (INIS)

    Reasor, M.J.; Lee, P.; Kirk, R.G.

    1990-01-01

    X-ray microanalysis has been used previously to study the accumulation of iodine in alveolar macrophages of rats treated with the iodinated drug, amiodarone. Due to metabolism of the drug in vivo, primarily to desethylamiodarone, it was not possible to identify the source of the iodine signal. In the present study we have utilized primary cell cultures of alveolar macrophages to study the intracellular accumulation of each of these drug species in vitro. Neither drug is metabolized by these cells in culture, permitting characterization of the accumulation of each independent of the other. Cells were incubated with equimolar concentrations of either amiodarone or desethylamiodarone for 42 hr, and X-ray microanalysis of freeze-dried cryosections of cells was used to quantify accumulation by monitoring the iodine signal associated with each drug. For both drug exposures, the highest iodine content was present in amorphous bodies and dense granules, consistent with the pattern following in vivo exposure. Higher levels of desethylamiodarone, compared to amiodarone, were measured in all compartments of the cells. The results of the in vitro investigation further demonstrate the utility of X-ray microanalysis in the study of the cellular response to amiodarone and desethylamiodarone

  7. Alteration of UV primary fluorescence of vital tumor cells following irradiation with neutrons and gamma rays

    International Nuclear Information System (INIS)

    Merkle, K.

    1980-01-01

    The change of UV primary fluorescence intensity of vital unstained cells of Ehrlich ascites carcinoma after 60 Co-gamma and neutron irradiation was investigated. The mean neutron energy was 6.2 MeV. Fluorescence intensity was detected using impulse cytophotometry. The UV intensity of single cells was measured in the spectral range from 300-400 nm. An monotonous increase of dose-effect curves and a maximum at 3.5 Gy (neutrons) and 30 Gy (γ-rays) was obtained. The first relevant increase of fluorescence intensity was detected at 0.4 Gy (neutrons) and 0.75 Gy (γ-rays). Factors influencing the increase and decrease of primary fluorescence behavior of vital cells are discussed. (author)

  8. Cell inactivation by ultrasoft X-rays: Role of inner shell ionization

    International Nuclear Information System (INIS)

    Abel, F.; du Penhoat, H.; Despiney-Bailly, I.

    1997-01-01

    The biological effect of K-electron removal in C, N, O atoms of the DNA needs to be systematically studied. A calculation of the RBE of X-rays around K-edges was performed to test experimental feasibility. Results obtained motivated an experimental study of the lethal effectiveness of C-K ionizations and experiments were performed with monochronized synchrotron radiation. Cell survival was studied with a V79 chinese hamster cell line, using cells grown as monolayers on mylar foil. The linear quadratic shape survival curves obtained for 250 eV and 340 eV radiation are discussed. (author)

  9. X-ray-enhanced cancer cell migration requires the linker of nucleoskeleton and cytoskeleton complex.

    Science.gov (United States)

    Imaizumi, Hiromasa; Sato, Katsutoshi; Nishihara, Asuka; Minami, Kazumasa; Koizumi, Masahiko; Matsuura, Nariaki; Hieda, Miki

    2018-04-01

    The linker of nucleoskeleton and cytoskeleton (LINC) complex is a multifunctional protein complex that is involved in various processes at the nuclear envelope, including nuclear migration, mechanotransduction, chromatin tethering and DNA damage response. We recently showed that a nuclear envelope protein, Sad1 and UNC84 domain protein 1 (SUN1), a component of the LINC complex, has a critical function in cell migration. Although ionizing radiation activates cell migration and invasion in vivo and in vitro, the underlying molecular mechanism remains unknown. Here, we examined the involvement of the LINC complex in radiation-enhanced cell migration and invasion. A sublethal dose of X-ray radiation promoted human breast cancer MDA-MB-231 cell migration and invasion, whereas carbon ion beam radiation suppressed these processes in a dose-dependent manner. Depletion of SUN1 and SUN2 significantly suppressed X-ray-enhanced cell migration and invasion. Moreover, depletion or overexpression of each SUN1 splicing variant revealed that SUN1_888 containing 888 amino acids of SUN1 but not SUN1_916 was required for X-ray-enhanced migration and invasion. In addition, the results suggested that X-ray irradiation affected the expression level of SUN1 splicing variants and a SUN protein binding partner, nesprins. Taken together, our findings supported that the LINC complex contributed to photon-enhanced cell migration and invasion. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

  10. Role of thyroid in x-ray-induced oncogenic transformation in cell culture

    International Nuclear Information System (INIS)

    Borek, C.

    1982-01-01

    This paper examines the role of thyroid hormones in x-ray-induced neoplastic transformation of C3H/10 T 1/2 cells. In addition, the delineation of the time when transformation is sensitive to T3, the dependence of transformation on T3 concentration, and the involvement of protein synthesis are studied. The results indicate that thyroid hormone plays a key role in the initiation of x-ray-induced neoplastic transformation and that induction of protein synthesis may mediate this response

  11. Rhodium(III) as a potentiator of the effects of X-rays on cells

    Energy Technology Data Exchange (ETDEWEB)

    Richmond, R C; Centilli, M A; Cross, M H; Powers, E L

    1986-08-01

    A rhodium compound, Rh(NH/sub 3/)/sub 3/Cl/sub 3/, does not sensitize the spores of Bacillus megaterium to X-rays. However, it is a very effective sensitizer of vegetative cells of Staphylococcus aureus, raising the sensitivity four times in O/sub 2/ and over 100 times in anoxia. The inhibition by oxygen of the sensitizing action of Rh(III), which operates over a wide range of (O/sub 2/), is noteworthy. These experiments were performed in saline-phosphate buffer using 50 kVp X-rays. The results are discussed in terms of the known radiation chemistry of this compound.

  12. Analysis of cell kinetics after gamma ray irradiation using anti-BrdU monoclonal antibody

    International Nuclear Information System (INIS)

    Akagi, Kiyoshi; Tanaka, Yoshimasa

    1989-01-01

    The cell cycle was analyzed using anti-BrdU monoclonal antibody, and changes in cell kinetics after gamma ray irradiation as evaluated by this BrdU-PI double staining were compared with those evaluated by the DNA histogram method based on PI staining. The effect of irradiation on the cell kinetics has been studied according primarily to the number of G2 blocked cells. By the present BrdU method, rapid transition of the G1-S phase was observed within 2 hours of irradiation, and then G1 block was observed. Cells in the S phase progressed to the G2 + M cells returned to the G1 phase after 18 or more hours. These initial G1 blocked cells induced by irradiation were confirmed for the fist time by the present BrdU-PI double staining. By the conventional method based on the DNA histogram, accurate determination of S cell fraction was difficult due to overlapping of the DNA contents of G1 cells and early S cells and those of late S cells and G2 cells. On the other hand, BrdU-PI double staining allowed direct differentiation of G1, S, and G2 + M cells, especially between G1-S and S-G2 + M cells. The analysis of cell kinetics using BrdU is advantageous over the conventional autoradiographic methods in that it allowed more rapid assay with very high sensitivity. In addition, BrdU is alrady used clinically as an enhancement agent in radiation therapy for cancer. The present method is considered to be indispensable for evaluation of the percentage of S cells in the tumor tissue and analysis of cell kinetics after irradiation and chemotherapy against cancer. (author)

  13. Assessment of pulmonary parenchyma perfusion with FAIR in comparison with DCE-MRI-Initial results

    Energy Technology Data Exchange (ETDEWEB)

    Fan Li [Department of Radiology, ChangZheng Hospital Affiliated to Second Military Medical University, No. 415 Fengyang Road, Shanghai 200003 (China)], E-mail: fanli0930@163.com; Liu Shiyuan [Department of Radiology, ChangZheng Hospital Affiliated to Second Military Medical University, No. 415 Fengyang Road, Shanghai 200003 (China); Sun Fei [GE Healthcare China (China)], E-mail: Fei.sun@med.ge.com; Xiao Xiangsheng [Department of Radiology, ChangZheng Hospital Affiliated to Second Military Medical University, No. 415 Fengyang Road, Shanghai 200003 (China)], E-mail: lizhaobin79@163.com

    2009-04-15

    Objective: The aim of this study was to assess pulmonary parenchyma perfusion with flow-sensitive alternating inversion recovery (FAIR) in comparison with 3D dynamic contrast-enhanced (DCE) imaging in healthy volunteers and in patients with pulmonary embolism or lung cancer. Materials and methods: Sixteen healthy volunteers and 16 patients with pulmonary embolism (5 cases) or lung cancer (11 cases) were included in this study. Firstly, the optimized inversion time of FAIR (TI) was determined in 12 healthy volunteers. Then, FAIR imaging with the optimized TI was performed followed by DCE-MRI on the other 4 healthy volunteers and 16 patients. Tagging efficiency of lung and SNR of perfusion images were calculated with different TI values. In the comparison of FAIR with DCE-MRI, the homogeneity of FAIR and DCE-MRI perfusion was assessed. In the cases of perfusion abnormality, the contrast between normal lung and perfusion defects was quantified by calculating a normalized signal intensity ratio. Results: One thousand milliseconds was the optimal TI, which generated the highest lung tagging efficiency and second highest PBF SNR. In the volunteers, the signal intensity of perfusion images acquired with both FAIR and DCE-MRI was homogeneous. Wedged-shaped or triangle perfusion defects were visualized in five pulmonary embolisms and three lung cancer cases. There was no significant statistical difference in signal intensity ratio between FAIR and DCE-MRI (P > 0.05). In the rest of eight lung cancers, all the lesions showed low perfusion against the higher perfused pulmonary parenchyma in both FAIR and DCE-MRI. Conclusion: Pulmonary parenchyma perfusion imaging with FAIR was feasible, consistent and could obtain similar functional information to that from DCE-MRI.

  14. Assessment of pulmonary parenchyma perfusion with FAIR in comparison with DCE-MRI-Initial results

    International Nuclear Information System (INIS)

    Fan Li; Liu Shiyuan; Sun Fei; Xiao Xiangsheng

    2009-01-01

    Objective: The aim of this study was to assess pulmonary parenchyma perfusion with flow-sensitive alternating inversion recovery (FAIR) in comparison with 3D dynamic contrast-enhanced (DCE) imaging in healthy volunteers and in patients with pulmonary embolism or lung cancer. Materials and methods: Sixteen healthy volunteers and 16 patients with pulmonary embolism (5 cases) or lung cancer (11 cases) were included in this study. Firstly, the optimized inversion time of FAIR (TI) was determined in 12 healthy volunteers. Then, FAIR imaging with the optimized TI was performed followed by DCE-MRI on the other 4 healthy volunteers and 16 patients. Tagging efficiency of lung and SNR of perfusion images were calculated with different TI values. In the comparison of FAIR with DCE-MRI, the homogeneity of FAIR and DCE-MRI perfusion was assessed. In the cases of perfusion abnormality, the contrast between normal lung and perfusion defects was quantified by calculating a normalized signal intensity ratio. Results: One thousand milliseconds was the optimal TI, which generated the highest lung tagging efficiency and second highest PBF SNR. In the volunteers, the signal intensity of perfusion images acquired with both FAIR and DCE-MRI was homogeneous. Wedged-shaped or triangle perfusion defects were visualized in five pulmonary embolisms and three lung cancer cases. There was no significant statistical difference in signal intensity ratio between FAIR and DCE-MRI (P > 0.05). In the rest of eight lung cancers, all the lesions showed low perfusion against the higher perfused pulmonary parenchyma in both FAIR and DCE-MRI. Conclusion: Pulmonary parenchyma perfusion imaging with FAIR was feasible, consistent and could obtain similar functional information to that from DCE-MRI.

  15. Possibilities of 99mTc-MIBI for imaging of the thyroid parenchyma

    International Nuclear Information System (INIS)

    Mluchkov, N.; Mluchkov, Kh.

    1998-01-01

    Thyroid parenchyma imaging is very important as an evidence of residual part of the gland in case of thyroidectomy. The determination of the mass of this part and its function is crucial at the substituting hormonal therapy. Also at cases of thyroid carcinomas the differential diagnosis of recurrences of radiation and/or postoperative fibrosis is difficult. The thyroid imaging by 131 I and by 99m Tc-pertechnetates is not always possible because of gland blockage from medicines, thyroid hormones and foods with high iodine content. The aim of this study was to establish if 99m Tc-MIBI could depict the thyroid parenchyma without being influenced by gland blockage giving a real image of it. A comparative scintigraphic study has been carried out at 58 patients with different thyroid diseases using 99m Tc-pertechnetate, 131 I and 99m Tc-MIBI. There were 17 patients with diffuse goiter, 27 with nodules (23 of normal activity and 4 with cold nodules), 3 patients with retrosternal goiter and 11 with thyroid carcinoma after surgery intervention. The visualization of the thyroid parenchyma with 99m Tc-MIBI was better than that with 99 0 m Tc-pertechnetate and no dependent on suppression of the gland. All nodules showed 99m Tc-MIBI uptake with the same intensity as the surrounding normal gland tissue. The scintigraphy with 99m Tc-MIBI was of no value for differential diagnosis of nodules. 99m Tc-MIBI scintigraphy could be successfully applied at patients with retrosternal thyroid goiter and for detecting a thyroid rest at patients with thyroid cancer after surgery intervention. (author)

  16. An unexpected caffeine-enhanced survival in x-ray-sensitive variant cells

    International Nuclear Information System (INIS)

    Utsumi, Hiroshi

    1985-01-01

    The sensitivity of normal Chinese hamster cell lines, V79 and CHO, mouse cell lines, L5178Y and L, and human HeLa cells to the killing effect of x-ray is enhanced with addition of caffeine following x-ray irradiation in a dose-dependent fashion. However, the survival rate of variant cell (V79-AL162/S-10) increased with addition of low concentration of caffeine (caffeine-enhanced survival phenomenon). Therefore, the effects of protein synthesis-inhibiting agents, such as cycloheximide and puromycin, on caffeine-enhanced survival phenomenon were examined. This phenomenon was completely abolished by the inhibitory agents, but not abolished by DNA synthesis-damaging agents, such as excess thymidine and aphidicolin. DNA-damaging physiochemical factors, such as neutrons, U.V., methyl methanesulfonate and mitomycin C, were examined in relation to variant cells' sensitivity and caffeine-enhanced survival phenomenon. V79-AL162/S-10 cells showed high sensitivity to the killing effect of mitomycin C, but their survival rate returned to the rate of normal V79-B310H cells with addition of caffeine. (Namekawa, K.)

  17. Abnormal sensitivity of some Cockayne's syndrome cell strains to UV- and γ-rays

    International Nuclear Information System (INIS)

    Deschavanne, P.J.; Chavaudra, N.; Fertil, B.; Malaise, E.P.

    1984-01-01

    Cockayne's syndrome (CS) is a rare autosomal recessive genetic disease. Using a colony assay in vitro, we studied the sensitivity of 5 CS cell strains and two normal ones to UV- and γ-irradiation. The 5 CS strains appear to be UV-hypersensitive but the sensitivity varies widely from one strain to another. Hypersensitivity to γ-rays has been reported for 4 out of the 5 CS cell strains investigated. Repair of potentially lethal damage (PLD) after UV- and γ-irradiation was investigated by using unfed plateau cell cultures. Under these conditions, control cells show a great capacity to repair PLD. The two CS strains, which are hypersensitive to both UV- and γ-irradiation, exhibit no or only little PLD repair after treatment. The response of CS cell strains after γ-irradiation suggests a genetic heterogeneity. Three complementation groups are described in CS cells when dealing with UV radiosensitivity. However, variations in γ-ray sensitivity are reported for cells within the same UV complementation group. (Auth.)

  18. Imaging and etching, soft x-ray microscopy on whole wet cells

    International Nuclear Information System (INIS)

    Gilbert, J.R.; Pine, J.

    1993-01-01

    The authors have produced images of whole wet tissue culture cells with the Stony Brook/BNL scanning transmission x-ray microscope (STXM). For fixed cells the authors have taken images at theoretical resolutions of ∼50-75nm, and in practice have measured FWHM of features down to near 100nm, without any exotic image processing. For unfixed (i.e., initially live) cells the authors have imaged with 100nm pixels and measured features down to 250nm. In order to do this the authors have developed, tested and used a wet cell for maintaining fixed or live cells on the STXM stage during imaging. The design of the wet cell and the culture substrates that go with it make the STXM compatible with almost all standard systems for surface adherent tissue culture. The authors will show some new images of whole wet fixed and unfixed cells, with visible sub-micron features. The authors will also report data that helps to characterize the tissue damage due to x-ray absorption during STXM imaging

  19. Pulmonary lymphangioleiomyomatosis: Analysis of disease manifestation by region-based quantification of lung parenchyma

    Energy Technology Data Exchange (ETDEWEB)

    Theilig, D., E-mail: dorothea.theilig@charite.de [Charité, Universitätsmedizin Berlin, Department of Radiology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin (Germany); Doellinger, F. [Charité, Universitätsmedizin Berlin, Department of Radiology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin (Germany); Kuhnigk, J.M. [Fraunhofer MEVIS, Universitaetsallee 29, 28359 Bremen (Germany); Temmesfeld-Wollbrueck, B.; Huebner, R.H. [Charité, Department of Pneumology, Augustenburger Platz 1, 13353 Berlin (Germany); Schreiter, N.; Poellinger, A. [Charité, Universitätsmedizin Berlin, Department of Radiology, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin (Germany)

    2015-04-15

    Highlights: •The distribution of cystic lesions in LAM was evaluated with quantitative CT. •There were more cystic lesions in the central lung compared to peripheral areas. •Cystic changes were more frequent in apical two thirds compared to lower third. •Results might help to obviate the need for biopsy in more cases. -- Abstract: Purpose: Lymphangioleiomyomatosis (LAM) is characterized by proliferation of smooth muscle tissue that causes bronchial obstruction and secondary cystic destruction of lung parenchyma. The aim of this study was to evaluate the typical distribution of cystic defects in LAM with quantitative volumetric chest computed tomography (CT). Materials and methods: CT examinations of 20 patients with confirmed LAM were evaluated with region-based quantification of lung parenchyma. Additionally, 10 consecutive patients were identified who had recently undergone CT imaging of the lung at our institution, in which no pathologies of the lung were found, to serve as a control group. Each lung was divided into three regions (upper, middle and lower thirds) with identical number of slices. In addition, we defined a “peel” and “core” of the lung comprising the 2 cm subpleural space and the remaining inner lung area. Computerized detection of lung volume and relative emphysema was performed with the PULMO 3D software (v3.42, Fraunhofer MEVIS, Bremen, Germany). This software package enables the quantification of emphysematous lung parenchyma by calculating the pixel index, which is defined as the ratio of lung voxels with a density <−950 HU to the total number of voxels in the lung. Results: Cystic changes accounted for 0.1–39.1% of the total lung volume in patients with LAM. Disease manifestation in the central lung was significantly higher than in peripheral areas (peel median: 15.1%, core median: 20.5%; p = 0.001). Lower thirds of lung parenchyma showed significantly less cystic changes than upper and middle lung areas combined (lower

  20. Chronic diseases of lung parenchyma in children: the role of imaging

    International Nuclear Information System (INIS)

    Haran Jogeesvaran, K.; Owens, Catherine M.

    2010-01-01

    Chronic diseases of the lung parenchyma (CDoLP) in children encompass a vast number of distinct clinico-pathological conditions. The prevalence of CDoLP has continued to increase in the last 10-15 years and the paediatric radiologist will therefore have to become more familiar with the imaging appearances of CDoLP. This review highlights some of the key imaging appearances of CDoLP, focussing mainly on airways disease. We also explore issues around technique optimisation and dose minimisation that remain of paramount importance in children. (orig.)

  1. Selective localization of IgG from cerebrospinal fluid to brain parenchyma

    DEFF Research Database (Denmark)

    Mørch, Marlene Thorsen; Forsberg Sørensen, Sofie; Khorooshi, Reza M. H.

    2018-01-01

    the cerebrospinal fluid and induce subpial and periventricular NMO-like lesions and blood-brain barrier breakdown, in a complement-dependent manner. To investigate how IgG trafficking from cerebrospinal fluid to brain parenchyma can be influenced by injury. IgG from healthy donors was intrathecally injected...... into the cerebrospinal fluid via cisterna magna at 1, 2, 4, or 7 days after a distal stereotactic sterile needle insertion to the striatum. Antibody deposition, detected by staining for human IgG, peaked 1 day after the intrathecal injection and was selectively seen close to the needle insertion. When NMO...

  2. X-ray-induced bystander response reduce spontaneous mutations in V79 cells

    International Nuclear Information System (INIS)

    Maeda, Munetoshi; Kobayashi, Katsumi; Matsumoto, Hideki; Usami, Noriko; Tomiya, Masanori

    2013-01-01

    The potential for carcinogenic risks is increased by radiation-induced bystander responses; these responses are the biological effects in unirradiated cells that receive signals from the neighboring irradiated cells. Bystander responses have attracted attention in modern radiobiology because they are characterized by non-linear responses to low-dose radiation. We used a synchrotron X-ray microbeam irradiation system developed at the Photon Factory, High Energy Accelerator Research Organization, KEK, and showed that nitric oxide (NO)-mediated bystander cell death increased biphasically in a dose-dependent manner. Here, we irradiated five cell nuclei using 10 × 10 µm 2 5.35 keV X-ray beams and then measured the mutation frequency at the hypoxanthine-guanosine phosphoribosyl transferase (HPRT) locus in bystander cells. The mutation frequency with the null radiation dose was 2.6 × 10 -5 (background level), and the frequency decreased to 5.3 × 10 -6 with a dose of approximately 1 Gy (absorbed dose in the nucleus of irradiated cells). At high doses, the mutation frequency returned to the background level. A similar biphasic dose-response effect was observed for bystander cell death. Furthermore, we found that incubation with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO), a specific scavenger of NO, suppressed not only the biphasic increase in bystander cell death but also the biphasic reduction in mutation frequency of bystander cells. These results indicate that the increase in bystander cell death involves mechanisms that suppress mutagenesis. This study has thus shown that radiation-induced bystander responses could affect processes that protect the cell against naturally occurring alterations such as mutations. (author)

  3. X-ray-sensitive mutants of Chinese hamster ovary cell line

    International Nuclear Information System (INIS)

    Jeggo, P.A.; Kemp, L.M.

    1983-01-01

    A standard technique of microbial genetics, which involves the transfer of cells from single colonies by means of sterile toothpicks, has been adapted to somatic cell genetics. Its use has been demonstrated in the isolation of X-ray-sensitive mutants of CHO cells. 9000 colonies have been tested and 6 appreciably X-ray-sensitive mutants were isolated. (D 10 values 5-10-fold of wild-type D 10 value.) A further 6 mutants were obtained which showed a slight level of sensitivity (D 10 values less than 2-fold of wild-type D 10 value). The 6 more sensitive mutants were also sensitive to bleomycin, a chemotherapeutic agent inducing X-ray-like damage. Cross-sensitivity to UV-irradiation and treatment with the alkylating agents, MMS, EMS and MNNG, was investigated for these mutants. Some sensitivity to these other agents was observed, but in all cases it was less severe than the level of sensitivity to X-irradiation. Each mutant showed a different overall response to the spectrum of agents examined and these appear to represent new mutant phenotypes derived from cultured mammalian cell lines. One mutant strain, xrs-7, was cross-sensitive to all the DNA-damaging agents, but was proficient in the repair of single-strand breaks. (Auth.)

  4. Molybdenum cell for x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures

    Science.gov (United States)

    Matsuda, Kazuhiro; Tamura, Kozaburo; Katoh, Masahiro; Inui, Masanori

    2004-03-01

    We have developed a sample cell for x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures. All parts of the cell are made of molybdenum which is resistant to the chemical corrosion of alkali metals. Single crystalline molybdenum disks electrolytically thinned down to 40 μm were used as the walls of the cell through which x rays pass. The crystal orientation of the disks was controlled in order to reduce the background from the cell. All parts of the cell were assembled and brazed together using a high-temperature Ru-Mo alloy. Energy dispersive x-ray diffraction measurements have been successfully carried out for fluid rubidium up to 1973 K and 16.2 MPa. The obtained S(Q) demonstrates the applicability of the molybdenum cell to x-ray diffraction measurements of fluid alkali metals at high temperatures and high pressures.

  5. Effects of neonatal. gamma. -ray irradiation on rat hippocampus: Pt. 1; Postnatal maturation of hippocampal cells

    Energy Technology Data Exchange (ETDEWEB)

    Represa, A; Dessi, F; Beaudoin, M; Ben-Ari, Y [Institut National de la Sante et de la Recherche Medicale (INSERM), 75 - Paris (France)

    1991-01-01

    The axons of dentate granule cells, the mossy fibres, establish synaptic contacts with the thorny excrescences of the apical dendrite of CA3 pyramidal neurons. Dentate granule cells develop postnatally in rats, whereas the CA3 pyramidal cells are generated before birth. In the present studies, using unilateral neonatal {gamma}-ray irradiation to destroy the granule cells in one hemisphere, we have studied the effect of mossy fibre deprivation on the development of their targets. We show that such ''degranulation'' prevents the normal development of giant thorny excrescences, suggesting that the development of thorny excrescences in CA3 pyramidal neurons is under the control of mossy fibres. In contrast, irradiation of the hippocampus of the neonatal rat does not affect the development of the dendritic arborization of CA3 pyramidal cells and their non-mossy dendritic spines. (author).

  6. Radio-sensitization of esophageal cancer EC9706 cells to X ray by histone deacetylase inhibiter Trichostatin A

    International Nuclear Information System (INIS)

    Lin Xiaoli; Qin Guangyong; Fang Huasheng; Zhang Fengqiu; Ya Huiyuan

    2009-01-01

    Cell apoptosis and the expression of DNA damage repair-related genes XRCC2, ATM and Lig4 were detected separately by flow cytometry analysis and real-time fluorescence quantitative (RT-PCR), in order to investigate the effect of Trichostatin A (TSA) pre-treatment on the radiosensitivity of esophageal cancer EC9706 cells to X ray in vitro. The results indicate that pre-irradiation exposure to TSA enhances cell apoptotic rate by X ray markedly (P<0.05) and the mRNA levels of XRCC2, ATM and Lig4 (except 8Gy) are up-regulated by X ray individually (P<0.05). TSA alone and TSA in combination with X ray all reduce mRNA levels of XRCC2, ATM and Lig4. In conclusions, TSA may radio-sensitize EC9706 cells to X ray by reducing mRNA levels of XRCC2, ATM and Lig4. (authors)

  7. Differential response of two cell lines sequentially irradiated with low X-ray doses.

    Science.gov (United States)

    Güerci, A M; Dulout, F N; Grillo, C A; Seoane, A I

    2005-05-01

    An experiment was designed to compare the effect of repeated low doses of X-rays in two different cell lines: one transformed, epithelial like and aneuploid Chinese hamster ovary K-1 (CHO-K1); the other originated from a human primary culture, fibroblast, diploid and non-transformed, MRC-5. CHO and MRC-5 cells were cultured for 14 or eight passages, respectively. Irradiation was performed once per passage when cells were in the quiescent state (90 - 95% in G1/G0). Cells were exposed to 10.0 mSv X-ray doses. Ionizing radiation did not induce apoptosis or necrosis in the exposed CHO cell population. Significant increases of low-level damaged cells (degrees 1 and 2) were found for the 14 cycles of radiation when compared with controls, except for the first irradiation cycle. No significant increases in the frequency of cells with severe damage were observed. The frequency of MRC-5 cells with low-level damage increased significantly when compared with controls for radiation cycles seven and eight. Significant increases of apoptosis, necrosis and severe damage were found only for the highest dose. Transformed and non-transformed cell types responded differently to direct and indirect damage using low-dose repeat exposures to ionizing radiation. Though more investigation is needed to understand the mechanisms of radiation effects in chronic low-dose-exposed cell populations, cellular type should be taken into account in the design of in vitro experiments for understanding low-dose-irradiation effects.

  8. Live-cell imaging study of mitochondrial morphology in mammalian cells exposed to X-rays

    International Nuclear Information System (INIS)

    Noguchi, M.; Yokoya, A.; Narita, A.; Fujii, K.; Kanari, Y.

    2015-01-01

    Morphological changes in mitochondria induced by X-irradiation in normal murine mammary gland cells were studied with a live-cell microscopic imaging technique. Mitochondria were visualised by staining with a specific fluorescent probe in the cells, which express fluorescent ubiquitination-based cell-cycle indicator 2 (Fucci2) probes to visualise cell cycle. In unirradiated cells, the number of cells with fragmented mitochondria was about 20 % of the total cells through observation period (96 h). In irradiated cells, the population with fragmented mitochondria significantly increased depending on the absorbed dose. Particularly, for 8 Gy irradiation, the accumulation of fragmentation persists even in the cells whose cell cycle came to a stand (80 % in G1 (G0-like) phase). The fraction reached to a maximum at 96 h after irradiation. The kinetics of the fraction with fragmented mitochondria was similar to that for cells in S/G2/M phase (20 %) through the observation period (120 h). The evidences show that, in irradiated cells, some signals are continually released from a nucleus or cytoplasm even in the G0-like cells to operate some sort of protein machineries involved in mitochondrial fission. It is inferred that this delayed mitochondrial fragmentation is strongly related to their dysfunction, and hence might modulate radiobiological effects such as mutation or cell death. (authors)

  9. [Raman spectra study on radiation damage in EC9706 cells by 60Cogamma-rays].

    Science.gov (United States)

    Qi, Jian; Guo, Zheng-Yuan; Zhang, Guang-Shui; Wu, Dian-Yong; Tang, Wei-Yue

    2009-07-01

    Raman spectrum was used to study the structure and content of protein, nucleic acid and fat, while EC9706 cells irradiated by 60Co gamma-ray were cultivated for 24 h. The results showed that for spectrum intensity and frequency deviation, there were big differences between each exposure group and control group. For the 1 244 cm(-1) peak of amide III, beta folder changed to disordered conformations in the middle dose (4, 5Gy) groups. The 1 341 cm(-1) peak of v (the indole ring of Trp) was red-shifted in every dose group. There was a 2-3 cm(-1) red shift at the 782 cm(-1) peak in the big dose groups (7, 8Gy). It was showed that the non-hydrogenation of v(s)(PO2-) was strengthened due to big dose gamma-rays radiation. There was a 4 cm(-1) blue shift at the 1 446 cm(-1) peak of delta (CH2, CH3). It maybe resulted from 60Co gamma-rays' damage to the film of EC9706 cells. The preferable dose of 60Co gamma-rays may be found by analyzing the variety of the above-mentioned peaks in some dose groups.

  10. An automatic extraction algorithm of three dimensional shape of brain parenchyma from MR images

    International Nuclear Information System (INIS)

    Matozaki, Takeshi

    2000-01-01

    For the simulation of surgical operations, the extraction of the selected region using MR images is useful. However, this segmentation requires a high level of skill and experience from the technicians. We have developed an unique automatic extraction algorithm for extracting three dimensional brain parenchyma using MR head images. It is named the ''three dimensional gray scale clumsy painter method''. In this method, a template having the shape of a pseudo-circle, a so called clumsy painter (CP), moves along the contour of the selected region and extracts the region surrounded by the contour. This method has advantages compared with the morphological filtering and the region growing method. Previously, this method was applied to binary images, but there were some problems in that the results of the extractions were varied by the value of the threshold level. We introduced gray level information of images to decide the threshold, and depend upon the change of image density between the brain parenchyma and CSF. We decided the threshold level by the vector of a map of templates, and changed the map according to the change of image density. As a result, the over extracted ratio was improved by 36%, and the under extracted ratio was improved by 20%. (author)

  11. Gastrointestinal parasite control during prepuberty improves mammary parenchyma development in Holstein heifers.

    Science.gov (United States)

    Perri, Adrián F; Mejía, Miguel E; Licoff, Nicolás; Diab, Santiago S; Formía, Néstor; Ornstein, Ana; Becú-Villalobos, Damasia; Lacau-Mengido, Isabel M

    2013-12-06

    Parasitism during development impairs normal growth and delays the onset of puberty through altered hormone profiles, including insulin-like growth factor one (IGF-1). As mammary gland development during prepuberty is strongly dependent on IGF-1, we determined if antiparasitic treatment during this stage of growth improved mammary gland development. One group of Holstein heifers was treated monthly, rotationally with antiparasitic drugs from birth to 70 weeks of age, a second group was untreated. Treated heifer calves had between 56% and 65% less EPG counts than untreated ones. Presence of Ostertagia, Cooperia, Haemonchus and Trichostrongylus was demonstrated. Treatment effectively advanced the onset of puberty and increased IGF-1 levels. At 20, 30, 40 and 70 weeks of age biopsies from the mammary gland were taken and histological sections were prepared and stained with hematoxylin-eosin. Pictures were analyzed to compare parenchyma area in relation to total mammary tissue between groups. Mammary samples from treated heifers had higher ratios of parenchyma/total area than untreated ones. As mammary development during prepuberty is crucial for mammary performance during lactation, these results add new evidence to the importance of gastrointestinal parasite control in heifers. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. A reaction cell for ambient pressure soft x-ray absorption spectroscopy

    Science.gov (United States)

    Castán-Guerrero, C.; Krizmancic, D.; Bonanni, V.; Edla, R.; Deluisa, A.; Salvador, F.; Rossi, G.; Panaccione, G.; Torelli, P.

    2018-05-01

    We present a new experimental setup for performing X-ray Absorption Spectroscopy (XAS) in the soft X-ray range at ambient pressure. The ambient pressure XAS setup is fully compatible with the ultra high vacuum environment of a synchrotron radiation spectroscopy beamline end station by means of ultrathin Si3N4 membranes acting as windows for the X-ray beam and seal of the atmospheric sample environment. The XAS detection is performed in total electron yield (TEY) mode by probing the drain current from the sample with a picoammeter. The high signal/noise ratio achievable in the TEY mode, combined with a continuous scanning of the X-ray energies, makes it possible recording XAS spectra in a few seconds. The first results show the performance of this setup to record fast XAS spectra from sample surfaces exposed at atmospheric pressure, even in the case of highly insulating samples. The use of a permanent magnet inside the reaction cell enables the measurement of X-ray magnetic circular dichroism at ambient pressure.

  13. X-ray tomography: Biological cells in 3-D at better than 50 nm resolution

    International Nuclear Information System (INIS)

    Larabell, C.; Le Gros, M.

    2004-01-01

    Full text: X-ray microscopy can be used to image whole, hydrated, specimens with a spatial resolution 5-10 times better than that obtained using visible light microscopy. X-ray imaging at photon energies below the K- absorption edge of oxygen, referred to as the water window, exploits the strong natural contrast for organic material embedded in a mostly water matrix. With a transmission X-ray microscope using Fresnel zone plate optics, specimens up to 10 microns thick can be examined. The highest X-ray transmission in hydrated samples is obtained at a wavelength of 2.4 nm but, due to the low numerical aperture of zone plate lenses operated in st order diffraction mode the structures resolved are much larger than the X-ray wavelength. Because of the low NA of X-ray lenses (NA=0.05), combined with the effect of polychromatic illumination and a wavelength dependant focal length, the effective depth of ld is large (6-10 microns). The experiments presented here were performed at the Advanced Light Source using the full ld transmission X-ray microscope, XM-1. This microscope employs a bend magnet X-ray source and zone plate condenser and objective lenses. The condenser zone plate acts as a monochromator and the X-ray images are recorded directly on a cooled, back-thinned 1024x1024 pixel CCD camera. The sample holder was a rotationally symmetric glass tube; the region containing the sample was 10 microns in diameter with a wall thickness of 200 nm. Live yeast cells were loaded into the tube, rapidly frozen by a blast of liquid nitrogen-cooled helium gas, and maintained at 140 deg C by a steady flow of cold helium. The image sequence spanned 180 deg and consisted of 45 images spaced by 4 deg. The images were aligned to a common axis and computed tomographic reconstruction was used to obtain the 3-D X-ray linear absorption coefficient. Volume rendering and animation of reconstructed data was performed using the 3-D program, Amira. Acquisition time for 90 images was 3 min

  14. Design of solar cell materials via soft X-ray spectroscopy

    DEFF Research Database (Denmark)

    Himpsel, F.J.; Cook, P.L.; de la Torre, G.

    2013-01-01

    This overview illustrates how spectroscopy with soft X-rays can assist the development of new materials and new designs for solar cells. The starting point is the general layout of a solar cell, which consists of a light absorber sandwiched between an electron donor and an electron acceptor....... There are four relevant energy levels that can be measured with a combination of X-ray absorption spectroscopy and photoelectron spectroscopy, as illustrated for an organic dye as absorber attached to a p-doped diamond film as donor. Systematic measurements of organometallic dyes (phthalocyanines and porphyrins......) as a function of the metal atom are presented for the metal 2p and N 1s absorption edges. In combination with density functional theory one can discern trends that are useful for tailoring absorber molecules. A customized porphyrin molecule is investigated that combines an absorber with a donor and a linker...

  15. Effects of selective bile duct ligation on liver parenchyma in young animals: histologic and molecular evaluations.

    Science.gov (United States)

    Tannuri, Ana Cristina A; Coelho, Maria Cecília M; de Oliveira Gonçalves, Josiane; Santos, Maria Mercês; Ferraz da Silva, Luiz Fernando; Bendit, Israel; Tannuri, Uenis

    2012-03-01

    The mechanisms of increased collagen production and liver parenchyma fibrosis are poorly understood. These phenomena are observed mainly in children with biliary obstruction (BO), and in a great number of patients, the evolution to biliary cirrhosis and hepatic failure leads to the need for liver transplantation before adolescence. However, pediatric liver transplantation presents with biliary complications in 20% to 30% of cases in the postoperative period. Intra- or extrahepatic stenosis of bile ducts is frequent and may lead to secondary biliary cirrhosis and the need for retransplantation. It is unknown whether biliary stenosis involving isolated segments or lobes may affect the adjacent nonobstructed lobes by paracrine or endocrine means, leading to fibrosis in this parenchyma. Therefore, the present study aimed to create an experimental model of selective biliary duct ligation in young animals with a subsequent evaluation of the histologic and molecular alterations in liver parenchyma of the obstructed and nonobstructed lobes. After a pilot study to standardize the surgical procedures, weaning rats underwent ligation of the bile ducts of the median, left lateral, and caudate liver lobes. The bile duct of the right lateral lobe was kept intact. To avoid intrahepatic biliary duct collaterals neoformation, the parenchymal connection between the right lateral and median lobes was clamped. The animals were divided into groups according to the time of death: 1, 2, 3, 4, and 8 weeks after surgical procedure. After death, the median and left lateral lobes (with BO) and the right lateral lobe (without BO [NBO]) were harvested separately. A group of 8 healthy nonoperated on animals served as controls. Liver tissues were subjected to histologic evaluation and quantification of the ductular proliferation and of the portal fibrosis. The expressions of smooth muscle α-actin (α-SMA), desmin, and transforming growth factor β1 genes were studied by molecular analyses

  16. X-ray induced polyploidization in the male germline cells of Poekilocerus pictus (acrididoidea : orthopta)

    International Nuclear Information System (INIS)

    Gururaj, M.E.; Rajasekarasetty, M.R.

    1977-01-01

    After the irradiation of male germline cells of Poekilocerus pictus with 20r, 40r, 80r, 120r doses of X-rays, both first and second meiotic polyploid cells were recovered. While various degrees of polyploidy were encountered in first meiotic cells, second meiotic polyploid cells, second meitoic polyploid cells contained diploid number of half bivalents only. The former never progressed beyond leptotene and showed symptoms of degeneration. Among the latter, a few cells showed either emainingative tendencies like uncoiling and stickiness or failure of cellsted meiosis successfully. It has been shown that the dicentric bridges and/or laggards in anaphase-I interfere with the elongation and regression of the spindle, thereby giving rise to metaphase-II polyploid cells through restitution. The possible role of fragmentation of chromosomes in decreasing the incidence of metaphase-II polyploid cells at higher doses of irradiation and the causes for the differential fate of the first and second meiotic polyploid cells have been discussed. (author)

  17. Variations in sensitivity of synchronized Chinese hamster cells to oxic and anoxic X-ray exposures

    International Nuclear Information System (INIS)

    Siracka, E.; Littbrand, B.; Clifton, K.H.; Revesz, L.

    1975-01-01

    V-79 Chinese hamster cells in monolayer cultures on glass surfaces were synchronized by treatment with hydroxyurea and then exposed at different times to X-rays in air or in oxygen-free argon. Survival determinations indicated that the oxygen enhancement ratio (OER) as expressed by the ratio of the respective D 0 values varied over a narrow range in the different phases of the cell cycle. These changes resulted from cyclic alterations in both aerobic and anaerobic D 0 values, possibly in n values. (author)

  18. Applicability of X-ray reflectometry to studies of polymer solar cell degradation

    DEFF Research Database (Denmark)

    Andreasen, Jens Wenzel; Gevorgyan, Suren; Schleputz, C.M.

    2008-01-01

    Although degradation of polymer solar cells is widely acknowledged, the cause, physical or chemical, has not been identified. The purpose of this work is to determine the applicability of X-ray reflectometry for in situ observation of physical degradation mechanisms. We find that the rough...... interfaces of the polymer solar cell constituent layers seriously obstruct the sensitivity of the technique, rendering it impossible to elucidate changes in the layer/interface structure at the sub-nanometer level. (c) 2008 Elsevier B.V. All rights reserved....

  19. A double cell for X-ray absorption spectrometry of atomic Zn

    CERN Document Server

    Mihelic, A; Arcon, I; Padeznik-Gomilsek, J; Borowski, M

    2002-01-01

    A high-temperature cell with a double wall design has been constructed for X-ray absorption spectrometry of metal vapors. The inner cell, assembled from a corundum tube and thin plates without welding or reshaping, serves as a container of the vapor sample. It is not vacuum tight: instead, the outer tube provides inert atmosphere. Several spectra of K-edge atomic absorption of Zn were obtained in the stationary working regime below the Zn boiling point. The K-edge profile shows an extremely strong resonance and, above the continuum threshold, coexcitations of the outer electrons.

  20. Exposure to power frequency magnetic fields suppresses X-ray-induced apoptosis transiently in Ku80-deficient xrs5 cells

    International Nuclear Information System (INIS)

    Tian, Furong; Nakahara, Takehisa; Yoshida, Masami; Honda, Naoko; Hirose, Hideki; Miyakoshi, Junji

    2002-01-01

    In an attempt to determine whether exposure to extremely low frequency (ELF) electromagnetic fields can affect cells, Ku80-deficient cells (xrs5) and Ku80-proficient cells (CHO-K1) were exposed to ELF electromagnetic fields. Cell survival, and the levels of the apoptosis-related genes p21, p53, phospho-p53 (Ser 15 ), caspase-3 and the anti-apoptosis gene bcl-2 were determined in xrs5 and CHO-K1 cells following exposure to ELF electromagnetic fields and X-rays. It was found that exposure of xrs5 and CHO-K1 cells to 60 Hz ELF electromagnetic fields had no effect on cell survival, cell cycle distribution and protein expression. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields for 5 h after irradiation significantly inhibited G 1 cell cycle arrest induced by X-rays (1 Gy) and resulted in elevated bcl-2 expression. A significant decrease in the induction of p53, phospho-p53, caspase-3 and p21 proteins was observed in xrs5 cells when irradiation by X-rays (8 Gy) was followed by exposure to 5 mT ELF magnetic fields. Exposure of xrs5 cells to the ELF electromagnetic fields for 10 h following irradiation significantly decreased X-ray-induced apoptosis from about 1.7% to 0.7%. However, this effect was not found in CHO-K1 cells within 24 h of irradiation by X-rays alone and by X-rays combined with ELF electromagnetic fields. Exposure of xrs5 cells to 60 Hz ELF electromagnetic fields following irradiation can affect cell cycle distribution and transiently suppress apoptosis by decreasing the levels of caspase-3, p21, p53 and phospho-p53 and by increasing bcl-2 expression

  1. Response of cultured human airway epithelial cells to X-rays and energetic α-particles

    International Nuclear Information System (INIS)

    Yang, T.C.; Holley, W.R.; Curtis, S.B.; Gruenert, D.C.; California Univ., San Francisco, CA

    1990-01-01

    Radon and its progeny, which emit α-particles during decay, may play an important role in inducing human lung cancer. To gain a better understanding of the biological effects of α-particles in human lung we studied the response of cultured human airway epithelial cells to X-rays and monoenergetic helium ions. Experimental results indicated that the radiation response of primary cultures was similar to that for airway epithelial cells that were transformed with a plasmid containing an origin-defective SV40 virus. The RBE for cell inactivation determined by the ratio of D 0 for X-rays to that for 8 MeV helium ions was 1.8-2.2. The cross-section for helium ions, calculated from the D 0 value, was about 24 μm 2 for cells of the primary culture. This cross-section is significantly smaller than the average geometric nuclear area (∼ 180 μm 2 ), suggesting that an average of 7.5 α-particles (8 MeV helium ions) per cell nucleus are needed to induce a lethal lesion. (author)

  2. X-ray induced alterations in the differentiation and mineralization potential of murine preosteoblastic cells

    Science.gov (United States)

    Hu, Yueyuan; Lau, Patrick; Baumstark-Khan, Christa; Hellweg, Christine E.; Reitz, Günther

    2012-05-01

    To evaluate the effects of ionizing radiation (IR) on murine preosteoblastic cell differentiation, we directed OCT-1 cells to the osteoblastic lineage by treatment with a combination of β-glycerophosphate (β-GP), ascorbic acid (AA), and dexamethasone (Dex). In vitro mineralization was evaluated based on histochemical staining and quantification of the hydroxyapatite content of the extracellular bone matrix. Expression of mRNA encoding Runx2, transforming growth factor β1 (TGF-β1), osteocalcin (OCN), and p21CDKN1A was analyzed. Exposure to IR reduced the growth rate and diminished cell survival of OCT-1 cells under standard conditions. Notably, calcium content analysis revealed that deposition of mineralized matrix increased significantly under osteogenic conditions after X-ray exposure in a time-dependent manner. In this study, higher radiation doses exert significant overall effects on TGF-β1, OCN, and p21CDKN1A gene expression, suggesting that gene expression following X-ray treatment is affected in a dose-dependent manner. Additionally, we verified that Runx2 was suppressed within 24 h after irradiation at 2 and 4 Gy. Although further studies are required to verify the molecular mechanism, our observations strongly suggest that treatment with IR markedly alters the differentiation and mineralization process of preosteoblastic cells.

  3. Effect of low dose X-ray irradiation on apoptosis in spermatogenic cells of mouse testes

    International Nuclear Information System (INIS)

    Liu Guangwei; Liu Shuchun; Lu Zhe; Gong Shouliang

    2003-01-01

    To study the effects of low dose radiation (LDR) with different doses of X-rays on the apoptosis in spermatogenic cells of male Kunming mouse testes. The time-effect and dose-effect of apoptosis in the different stages of spermatogenic cell cycles of mouse testis after LDR with different doses of X-rays were studied with light microscope using the methods of TdT-mediated dUTP nick end labeling (TUNEL) and HE staining. The apoptosis of spermatogenic cells induced by LDR had a remarkable regularity in cell types. When the dose was 0.025 Gy, spermatogonium apoptosis was taken as main. With the dose increase of irradiation (0.025-0.2 Gy), spermatocytes also showed an apoptotic change, but the apoptotic rate of spermatogonia was significantly higher than that of spermatocytes. Moreover, the apoptosis of spermatids and spermatozoa scarcely occurred after irradiation with low dose. The apoptosis of spermatogenic cells induced by LDR has a regular change, which provides a further experimental evidence for the mechanism study of hormesis by LDR

  4. X-rays effects on cytoskeleton mechanics of healthy and tumor cells.

    Science.gov (United States)

    Panzetta, Valeria; De Menna, Marta; Musella, Ida; Pugliese, Mariagabriella; Quarto, Maria; Netti, Paolo A; Fusco, Sabato

    2017-01-01

    Alterations in the cytoskeleton structure are frequently found in several diseases and particularly in cancer cells. It is also through the alterations of the cytoskeleton structure that cancer cells acquire most of their common features such as uncontrolled cell proliferation, cell death evasion, and the gaining of migratory and invasive characteristics. Although radiation therapies currently represent one of the most effective treatments for patients, the effects of X-irradiation on the cytoskeleton architecture are still poorly understood. In this case we investigated the effects, over time of two different doses of X-ray irradiation, on cell cytoskeletons of BALB/c3T3 and Sv40-transformed BALB/c 3T3 cells (SVT2). Biophysical parameters - focal adhesion size, actin bundles organization, and cell mechanical properties - were measured before and after irradiations (1 and 2 Gy) at 24 and 72 h, comparing the cytoskeleton properties of normal and transformed cells. The differences, before and after X-irradiation, were revealed in terms of cell morphology and deformability. Finally, such parameters were correlated to the alterations of cytoskeleton dynamics by evaluating cell adhesion at the level of focal adhesion and cytoskeleton mechanics. X-irradiation modifies the structure and the activity of cell cytoskeleton in a dose-dependent manner. For transformed cells, radiation sensitively increased cell adhesion, as indicated by paxillin-rich focal adhesion, flat morphology, a well-organized actin cytoskeleton, and intracellular mechanics. On the other hand, for normal fibroblasts IR had negligible effects on cytoskeletal and adhesive protein organization. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. Cytogenetic adaptive response of cultured fish cells to low doses of X-rays

    International Nuclear Information System (INIS)

    Kurihara, Yasuyuki; Etoh, Hisami; Rienkjkarn, M.

    1992-01-01

    The adaptive response was examining chromosomal aberrations and micronucleus in cultured fish cells, ULF-23 (mudminnow) and CAF-31 (gold fish). When cultured fish cells were first irradiated with small doses of X-rays, they became less sensitive to subsequent exposures to high doses. The effective adaptive dose was 4.8 cGy-9.5 cGy. Adaptive doses given cells in the G1 phase were more effective than when given in the S phase. The adaptive response was maximal at 5 hours and disappeared at 10 hours after the adaptive dose. The expression of the response was inhibited by treatment with 3-aminobenzamide, as reported for mammalian cells, and with arabinofuranoside cytosine, an inhibitor of DNA polymerase alpha. Caffeine, an inhibitor of post-replicational repair, had no effect on the response. (author)

  6. Cytogenetic adaptive response of cultured fish cells to low doses of X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Kurihara, Yasuyuki; Etoh, Hisami (National Inst. of Radiological Sciences, Chiba (Japan)); Rienkjkarn, M.

    1992-12-01

    The adaptive response was examining chromosomal aberrations and micronucleus in cultured fish cells, ULF-23 (mudminnow) and CAF-31 (gold fish). When cultured fish cells were first irradiated with small doses of X-rays, they became less sensitive to subsequent exposures to high doses. The effective adaptive dose was 4.8 cGy-9.5 cGy. Adaptive doses given cells in the G1 phase were more effective than when given in the S phase. The adaptive response was maximal at 5 hours and disappeared at 10 hours after the adaptive dose. The expression of the response was inhibited by treatment with 3-aminobenzamide, as reported for mammalian cells, and with arabinofuranoside cytosine, an inhibitor of DNA polymerase alpha. Caffeine, an inhibitor of post-replicational repair, had no effect on the response. (author).

  7. Micronucleus formation compared to the survival rate of human melanoma cells after X-ray and neutron irradiation and hyperthermia

    Energy Technology Data Exchange (ETDEWEB)

    van Beuningen, D.; Streffer, C.; Bertholdt, G.

    1981-09-01

    After neutron and X-ray irradiation and combined X-ray irradiation and hyperthermia (3 hours, 42/sup 0/C), the survival rate of human melanoma cells was measured by means of the colony formation test and compared to the formation of micronuclei. Neutrons had a stronger effect on the formation of micronuclei than the combination of X-rays and hyperthermia. X-rays had the lowest effect. The dose effect curve showed a break at that dose level at which a reduction of cells was observed in the cultures. A good relation between survival rate and formation of micronuclei was found for the X-ray irradiation, but not for the neutron irradiation and the combined treatment. These observations are discussed. At least for X-rays, the micronucleus test has turned out to be a good screening method for the radiosensitivity of a biologic system.

  8. DNA damage and γH2AX expression in EJ cells induced by 60Co gamma-rays

    International Nuclear Information System (INIS)

    Pan Yan; Tian Mei; Liu Jianxiang; Ruan Jianlei; Su Xu

    2009-01-01

    Objective: To investigate 60 Co γ-rays induced DNA damage of human bladder cancer cell line EJ cells and the relationship between different doses of 60 Co γ-rays, γH2AX foci number and γH2AX expression level. Methods: EJ cells were exposed to different doses of 60 Co γ-rays and the oliver tail moment (TM) of EJ cells were analyzed with single cell gel electrophoresis (SCGE) . Immunofluorescent microscopy was used to analysis γH2AX foci formation in EJ cells after exposure to different doses of γ-ray irradiation and time-course after exposure to 2 Gy γ-ray irradiation. FACSAria was used to detect the changes of γH2AX protein expression in EJ cells. Results: The TMs of EJ cells were increased with the irradiation dose. The TM of 0 Gy group and 4 Gy group was 0.24 and 5.26, respectively. Immunofluorescent analysis demonstrated that γH2AX foci could be induced by γ-ray irradiation in dose-dependent and time-dependent manners. The foci number and size in nuclei of EJ cells was significantly increased after exposed to different doses of γ-ray irradiation and the foci remained detectable at 24 h after exposed to irradiation. The dose range in which foci could be clearly detected was from 0.1 to 4 Gy. FACSDiva showed that γH2AX protein expression was increased after exposure to different doses of γ-ray irradiation. γH2AX protein expression level of 0.1 Gy group and 4 Gy group was 7.4% and 29.2% , respectively. Conclusions: γH2AX foci could be the most sensitive indicator for DNA damage and repair in mammalian cells, and it might be a new biomarker for radiological emergency. (authors)

  9. Pharmacologic requirements for obtaining sensitization of human tumor cells in vitro to combined 5-fluorouracil or ftorafur and x rays

    International Nuclear Information System (INIS)

    Byfield, J.E.; Calabro-Jones, P.; Klisak, I.; Kulhanian, F.

    1982-01-01

    The combined effects of X ray and 5-fluorouracil (5-FU) in tissue culture have been studied using two human adenocarcinoma lines (HeLa and HT-29 cells). Both showed similar sensitivities to 5-FU, HeLa cells appearing somewhat more resistant to higher concentrations. Combined treatment of both cell types with 5-FU and X rays led to a time-dependent enhancement of cell killing (''radiosensitization''). Only post-radiation incubation had any effect, prior exposure to 5-FU being strictly additive. Enhanced cell killing by combined 5-FU and X rays could not be explained by either the infliction of additional acute damage in the immediate post-radiation period or an inhibitory effect of 5-FU on the repair of sub-lethal X ray injury. Rather, the enhanced cytotoxicity proved to be dependent on a damage expressed in time periods exceeding the duration of a cell doubling time in vitro. Overall, the data equally suggest that X rays may sensitize the cells to 5-FU. The enhanced cell killing is maximized if the cells are continuously exposed to 5-FU for 48 hours following the X ray exposure. These results indicate that clinical treatment regimens might be useful in evaluating 5-FU infusional scheduling in accordance with these unique requirements, which are not met by conventional bolus 5-FU and X ray therapy fractionation regimens. Ftorafur, a drug proposed to act as a slow release form of 5-FU, was found to show limited cytotoxic potential in vitro and did not significantly enhance cell killing after X ray exposure

  10. Evidence that a recombinationless strain, rad 51, of Saccharomyces cerevisiae lacks the budding cell resistance to γ-rays

    International Nuclear Information System (INIS)

    Hama-Inaba, Hiroko; Saeki, Tetsuya

    1975-01-01

    The radiosensitivities of a wild-type and x-ray sensitive mutant, rad 51 (defective in genetic recombination) of Saccharomyces cerevisiae to γ-rays were compared, using non-synchronized and partially synchronized cultures. The rad 51 cells, either haploid or diploid, showed only very small changes in radiosensitivity during cell growth, whereas the wild-type cells, especially haploid, showed the well-known budding resistance. The heterozygous (wild/rad 51) diploid cells showed in a survival curve a remarkable budding resistance and sigmoidal inactivation kinetics similar to those of wild-type homozygous diploid cells. (author)

  11. Genomic instability induced by 137Cs γ-ray irradiation in CHL surviving cells

    International Nuclear Information System (INIS)

    Yue Jingyin; Liu Bingchen; Wu Hongying; Zhou Jiwen; Mu Chuanjie

    1999-01-01

    Objective: To study in parallel several possible manifestations of instability of surviving CHL cells after irradiation, namely the frequencies of mutation at locus, micronuclei and apoptosis. Methods: The frequencies of mutation at HGPRT locus, micronuclei and apoptosis were assayed at various times in surviving cells irradiated with γ-rays. Results: The surviving cells showed a persistently increased frequency of mutation at the HGPRT locus after irradiation until 53 days. Mutant fraction as high as 10 -4 was scored, tens of times higher than those assayed in control cells studied in parallel. The frequency of bi nucleated cells with micronuclei determined within 24 hours after irradiation increased with dose and reached a peak value of (26.58 +- 2.48)% at 3 Gy, decreasing at higher doses to a plateau around 20%. The micronucleus frequency decreased steeply to about (14.47 +- 2.39)% within the first 3 days post-irradiation, and fluctuated at around 10% up to 56 days post-irradiation. The delayed efficiency of irradiated cells was significantly decreased. The frequency of apoptosis peaked about (24.90 +- 4.72)% at 10 Gy 48 h post-irradiation (γ-ray dose between 3-10 Gy) and then decreased to about 12% within 3 days. It was significantly higher than in control cells until 14 days. Conclusions: It shows that genomic instability induced by radiation can be transmitted to the progeny of surviving cells and may take many forms of expression such as lethal mutation, chromosome aberrations, gene mutation, etc

  12. Influence of DMSO on Carbon K ultrasoft X-rays induced chromosome aberrations in V79 Chinese hamster cells

    Energy Technology Data Exchange (ETDEWEB)

    Natarajan, Adayapalam T., E-mail: natarajan@live.nl [University of Tuscia, Viterbo (Italy); Palitti, Fabrizio [University of Tuscia, Viterbo (Italy); Hill, Mark A. [CRUK/MRC Gray Institute for Radiation Oncology and Biology, University of Oxford, Old Road Campus Research Building, Oxford OX3 7DQ (United Kingdom); MRC Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD (United Kingdom); Stevens, David L. [MRC Radiation and Genome Stability Unit, Harwell, Oxfordshire OX11 0RD (United Kingdom); Ahnstroem, Gunnar [Department of Microbiology and Genetic Toxicology, Stockholm University, Stockholm (Sweden)

    2010-09-10

    Ultrasoft X-rays have been shown to be very efficient in inducing chromosomal aberrations in mammalian cells. The present study was aimed to evaluate the modifying effects of DMSO (a potent scavenger of free radicals) on the frequencies of chromosome aberrations induced by soft X-rays. Confluent held G1 Chinese hamster cells (V79) were irradiated with Carbon K ultrasoft X-rays in the presence and absence of 1 M DMSO and frequencies of chromosome aberrations in the first division cells were determined. DMSO reduced the frequencies of exchange types of aberrations (dicentrics and centric rings) by a factor of 2.1-3.5. The results indicate that free radicals induced by ultrasoft X-rays contribute to a great extent to the induction of chromosome aberrations. The possible implications of these results in interpreting the mechanisms involved in the high efficiency of ultrasoft X-rays in the induction of chromosome aberrations are discussed.

  13. Radioresistant cell strain of human fibrosarcoma cells obtained after long-term exposure to X-rays

    International Nuclear Information System (INIS)

    Wei, K.; Kodym, R.

    1998-01-01

    A radioresistant cell strain from human fibrosarcoma HT1080 has been obtained after prolonged exposure to x-rays for 7 months (2 Gy per day, 5 days per week). This new strain, HT1080R, differs from HT1080 in a significantly increased ability of clonogenical survival, with coefficient α decreasing from 0.161 to 0.123 Gy -1 and coefficient β decreasing from 0.0950 to 0.0565 Gy -2 . Furthermore, the radioresistance of HT1080R proved to be stable in long-term passaged cultures as well as in frozen samples. Differences between the two cell lines are also observed in the G-banded karyotype; the new cell line shows monosomy of chromosome 17 and loss of 5p + and 11q + present in the parental cells. These data suggest that the radioresistance may have been caused by radiation-induced cell mutation and that the resistant cells may have been selected by repeated irradiations. In order to characterize this new strain, the ability of the cells to rejoin DNA double-strand breaks, the cell cycle distribution and the amount of apoptosis after irradiation have been estimated; however, no differences are observed between these two cell strains. Although the mechanism of the elevated radioresistance remains unknown, this pair of cell strains can provide a new model system for further investigations with regard to the mechanisms of cellular radioresistance. The results also show that any type of irradiation similar to the schedules used in radiotherapy can lead to the formation and selection of more radioresistant cell clones in vitro, a phenomenon with possible implications for radiotherapy. (orig.)

  14. Sporadic insulinomas on volume perfusion CT: dynamic enhancement patterns and timing of optimal tumour-parenchyma contrast

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Liang; Xue, Hua-dan; Liu, Wei; Wang, Xuan; Sun, Hao; Li, Ping; Jin, Zheng-yu [Peking Union Medical College Hospital, Department of Radiology, Beijing (China); Wu, Wen-ming; Zhao, Yu-pei [Peking Union Medical College Hospital, Department of General Surgery, Beijing (China)

    2017-08-15

    To assess enhancement patterns of sporadic insulinomas on volume perfusion CT (VPCT), and to identify timing of optimal tumour-parenchyma contrast. Consecutive patients who underwent VPCT for clinically suspected insulinomas were retrospectively identified. Patients with insulinomas confirmed by surgery were included, and patients with familial syndromes were excluded. Two radiologists evaluated VPCT images in consensus. Tumour-parenchyma contrast at each time point was measured, and timing of optimal contrast was determined. Time duration of hyperenhancement (tumour-parenchyma contrast >20 Hounsfield units, HU) was recorded. Perfusion parameters were evaluated. Three dynamic enhancement patterns were observed in 63 tumours: persistent hyperenhancement (hyperenhancement time window ≥10 s) in 39 (61.9%), transient hyperenhancement (hyperenhancement <10 s) in 19 (30.2%) and non-hyperenhancement in 5 (7.9%). Timing of optimal contrast was 9 s after abdominal aorta threshold (AAT) of 200 HU, with tumour-parenchyma contrast of 77.6 ± 57.2 HU. At 9 s after AAT, 14 (22.2%) tumours were non-hyperenhancing, nine of which had missed transient hyperenhancement. Insulinomas with transient and persistent hyperenhancement patterns had significantly increased perfusion. Insulinomas have variable enhancement patterns. Tumour-parenchyma contrast is time-dependent. Optimal timing of enhancement is 9 s after AAT. VPCT enables tumour detection even if the hyperenhancement is transient. (orig.)

  15. Structural organization of the thyroid gland and interrenal tissue with reference to endocrine parenchyma in short mackerel, Rastrelliger brachysoma (Bleeker, 1851

    Directory of Open Access Journals (Sweden)

    Sinlapachai Senarat

    2016-01-01

    Full Text Available The first investigations of the thyroid gland and interrenal tissue with reference to the endocrine parenchyma of short mackerel Rastrelliger brachysoma were subjected to histological analysis. Specimens were collected during the fishing season (October to November 2013 from the Upper Gulf of Thailand. Under a light microscope, the thyroid gland of R. brachysoma was distinctly found located within the branchial region. Within this gland, it consists of several follicles among afferent brachial arteries. Each follicle exclusively contained a colloid that was surrounded by a simple, cuboidal, follicle epithelium. Histological study showed that the localization of interrenal tissue was in the anterior kidney. This tissue was composed of two parts based on the structural compositions and cell types; (i the stromal compartment was constituted of various interrenal cells and (ii the interstitial compartment contained the connective tissue, leucocytes and blood sinuses, with reference to the lymphatic tissue.

  16. X-ray induced degradation of DNA in Aspergillus nidulans cells comparative analysis of UV- and X-ray induced DNA degradation

    International Nuclear Information System (INIS)

    Zinchenko, V.V.; Babykin, M.M.

    1980-01-01

    Irradiating cells of Aspergillus nidulans of the wild type in the logarythmical growth phase with X-rays leads to a certain retention in DNA synthesis. This period is characterized by an insignificant fermentative DNA degradation connected with a process of its repair. There is no direct dependence between the radiation dose and the level of DNA degradation. The investigation of X-ray induced DNA degradation in a number of UVS-mutants permits to show the existence of two branches of DNA degradation - dependent and independent of the exogenic energy source. The dependence of DNA degradation on albumen synthesis prior to irradiation and after it, is demonstrated. It is supposed that the level of X-ray induced DNA degradation is determined by two albumen systems, one of which initiates degradation and the other terminates it. The comparative analysis of UV and X-ray induced DNA degradation is carried out

  17. Effects of drugs, x-rays, and heat on Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Tomasovic, S.P.

    1977-01-01

    The mitotic cell selection technique was used to monitor the effects of various drugs, primarily inhibitors of RNA synthesis, on x-ray-induced G2 delay. Addition of actinomycin D (2 μg/ml), caffeine (19--194 μg/ml), theophylline (18--180 μg/ml), or cordycepin (5--30 μg/ml) immediately before or after irradiation greatly reduced G2 delay and shifted the x-ray transition point (X-TP, the point in G2 beyond which cells are unaffected in their progression by x-rays) away from division. The magnitude of this protective effect increased with concentration. Addition of dimethylsulfoxide (10 6 μg/ml) immediately after irradiation reduced G2 delay but had no effect on the X-TP. The addition of 2-mercapto-1(β-4-pyridethyl) benzimidazole (25--75 μg/ml) or lucanthone (5--20 μg/ml) immediately before irradiation resulted in increased G2 delay, and shifted the X-TP closer to division. Studies of the effects of these drugs on incorporation of tritiated uridine or tritiated leucine into acid insoluble material indicated no correlation between reduction of G2 delay and rates of overall RNA or protein synthesis. Synchronous cells, treated continuously with 15 μg/ml of cordycepin starting in the latter part of S phase, proceeded into mitosis about 30 minutes ahead of controls. Howevr, cordycepin did not reduce mitotic delay observed for cells irradiated in S phase. Continuous treatment during G2 of unirradiated synchronous cells with 15 μg/ml of cordycepin had little effect on accelerating cells into mitosis, yet did reduce delay observed for cells irradiated in G2. These results are consistent with hypotheses requiring synthesis during G2 of critical protein molecules essential for mitosis. Heating mammalian cells induces lethality by an undetermined mechanism. Heat treatment of Chinese hamster ovary cells at 45.5 0 C resulted in an increase in nonhistone protein isolated with DNA

  18. Cell inactivation and chromosomal aberrations induced by X-rays and fast neutrons in cells of the Chinese hamster. 1

    International Nuclear Information System (INIS)

    Tolkendorf, E.

    1979-01-01

    Asynchronously grown cultures of Chinese hamster cells V79-4 were irradiated in suspension with 180 kV X-rays and fast neutrons (average energy of 6.2 MeV). The damage was assessed by measuring cell survival and frequencies of chromosome aberrations in the first post-irradiation metaphases. The experimental data for survival and chromosome aberrations were fitted by computer programmes. From the fitted curves the relative biological effectiveness (RBE) of fast neutrons was calculated. The RBE shows a similar dose dependence for killed and aberrant cells. The RBE decreases with increasing dose and amounts to approximately 5 for both effects for small neutron doses. The highest RBE is found for asymmetrical chromosomal exchanges and is dependent on the neutron dose, too. However, for isochromatid deletions the RBE is dose independent with a value of 3.6. (author)

  19. Using Dark Field X-Ray Microscopy To Study In-Operando Yttria Stabilized Zirconia Electrolyte Supported Solid Oxide Cell

    DEFF Research Database (Denmark)

    Sierra, J. X.; Poulsen, H. F.; Jørgensen, P. S.

    Dark Field X-Ray Microscopy is a promising technique to study the structure of materials in nanometer length scale. In combination with x-ray diffraction technique, the microstructure evolution of Yttria Stabilized Zirconia electrolyte based solid oxide cell was studied running at extreme operating...

  20. Design of Molecular Solar Cells via Feedback from Soft X-ray Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Himpsel, Franz J. [Univ. of Wisconsin, Madison, WI (United States)

    2015-06-12

    Spectroscopy with soft X-rays was used to develop new materials and novel designs for solar cells and artificial photosynthesis. In order to go beyond the widely-used trial-and-error approach of gradually improving a particular design, we started from the most general layout of a solar cell (or a photo-electrochemical device) and asked which classes of materials are promising for best performance. For example, the most general design of a solar cell consists of a light absorber, an electron donor, and an electron acceptor. These are characterized by four energy levels, which were measured by a combination of spectroscopic X-ray techniques. Tuning synchrotron radiation to the absorption edges of specific elements provided element- and bond-selectivity. The spectroscopic results were complemented by state-of-the-art calculations of the electronic states. These helped explaining the observed energy levels and the orbitals associated with them. The calculations were extended to a large class of materials (for example thousands of porphyrin dye complexes) in order to survey trends in the energy level structure. A few highlights serve as examples: 1) Organic molecules combining absorber, donor, and acceptor with atomic precision. 2) Exploration of highly p-doped diamond films as inert, transparent electron donors. 3) Surface-sensitive characterization of nanorod arrays used as photoanodes in water splitting. 4) Computational design of molecular complexes for efficient solar cells using two photons.

  1. X-ray induction of immortalization in primary rat embryo cells associated with and without tumorigenicity

    International Nuclear Information System (INIS)

    Sierra, E.; Oberley, L.W.; Guernsey, D.L.

    1985-01-01

    Cultures of primary rat embryo fibroblasts were irradiated with X-rays (3 Gy). After 14 days the majority of colonies in both irradiated and control plates had senesced. Surviving clones were ring isolated from irradiated and control plates and grown in culture. A phase of rapid proliferation after isolation was observed, followed by a decline (crisis) leading to senescence. Several clones from the irradiated plates were able to recover from this crisis and gave rise to continuous cell lines, while all colonies from control plates senesced. Three types of cells have been identified among the irradiated survivors: (1) immortal fully transformed, capable of growth in soft agar (Aga/sup +/) and tumor formation, (2) immortal normal, not able to grow in soft agar (Aga/sup -/) and nontumorigenic, and (3) immortal Aga/sup -/ cells which progressed to malignancy (Aga/sup +/, tumorigenicity) after further sub-culture. These data support the suggestion that X-rays can induce immortalization of mammalian cells in the absence of tumorigenicity, in addition to (and separate from) the fully tumorigenetic state

  2. Chromosome condensation may enhance X-ray-related cell lethality in a temperature-sensitive mutant (tsBN2) of baby hamster kidney cells (BHK21)

    International Nuclear Information System (INIS)

    Sasaki, H.; Nishimoto, T.

    1987-01-01

    In the tsBN2 cell line, which has a temperature-sensitive defect in the regulatory mechanism for chromosome condensation, the lethal effect of X rays was enhanced by incubating the cells at a nonpermissive temperature (40 degrees C) following X irradiation. This enhancement was suppressed in the presence of cycloheximide, which inhibits induction of premature chromosome condensation. The findings obtained in the case of delayed incubation at 40 degrees C and in synchronized cells indicate that X-ray-related potentially lethal damage, which can be expressed by chromosome condensation, is produced in the cells at any stage of the cell cycle, but it is repairable for all cells except those at around the late G2-M phase, where chromosome condensation occurs at a permissive temperature (33.5 degrees C). These observations suggest that the high sensitivity of late G2-M cells to X rays is caused by the events associated with chromosome condensation

  3. Quantifying trace elements in individual aquatic protist cells with a synchrotron x-ray fluorescence microprobe

    International Nuclear Information System (INIS)

    Twining, B.S.; Baines, S.B.; Fisher, N.S.; Maser, J.; Vogt, S.; Jacobsen, C.; Tovar-Sanchez, A.; Sanudo-Wihelmy, S.A.

    2003-01-01

    The study of trace metal cycling by aquatic protists is limited by current analytical techniques. Standard 'bulk' element analysis techniques that rely on physical separations to concentrate cells for analysis cannot separate cells from co-occurring detrital material or other cells of differing taxonomy or trophic function. Here we demonstrate the ability of a synchrotron-based X-ray fluorescence (SXRF) microprobe to quantify the elements Si, Mn, Fe, Ni, and Zn in individual aquatic protist cells. This technique distinguishes between different types of cells in an assemblage and between cells and other particulate matter. Under typical operating conditions, the minimum detection limits are 7.0 x 10 -16 mol μm -2 for Si and between 5.0 x 10 -20 and 3.9 x 10 -19 mol μm -2 for Mn, Fe, Ni, and Zn; this sensitivity is sufficient to detect these elements in cells from even the most pristine waters as demonstrated in phytoplankton cells collected from remote areas of the Southern Ocean. Replicate analyses of single cells produced variations of <5% for Si, Mn, Fe, and Zn and <10% for Ni. Comparative analyses of cultured phytoplankton cells generally show no significant differences in cellular metal concentrations measured with SXRF and standard bulk techniques (spectrophotometry and graphite furnace atomic absorption spectrometry). SXRF also produces two-dimensional maps of element distributions in cells, thereby providing information not available with other analytical approaches. This technique enables the accurate and precise measurement of trace metals in individual aquatic protists collected from natural environments.

  4. Combined effect of Taliblastine and gamma rays on the hereditary structure in somatic cells

    International Nuclear Information System (INIS)

    Khadzhidekova, B.

    1983-01-01

    It was established that the effect on normal human embrio lung fibroblasts was proportional to its concentration and the broth used; the cell growth is fully suspended by 20 mkg/ml. The Taliblastine blocks the mitosis and leads to metaphasal accumulation in the model systems under study: human embrio fibroblasts ''in vitro'' and rat bone marrow ''in vivo''. Tetrafloid cells are developed under the influence of Taliblastine. The poliploidgenic effect of Taliblastine is due to the metaphasic block. Taliblastine damages the hromozome stucture directly. Its clastogenic effect both ''in vitro'' and ''in vivo'' is much weaker than the radiation factor (2 cy gamma rays) one. Under the simultaneous influence of Taliblastine and gamma rays ''in vitro'' the mutagenic effect is a summary one. The mutagenic effect is intensified when the maximum effect times coincide. Both Taliblastine and gamma rays show a specific surpression of the synthesis of nuecleic acids and proteins. The Taliblastine on the protein synthesis is more clearly marked. The DNA synthesis is most sensitive to radiation. When combined with the radiation factor, it has the decisive effect. (authors)

  5. Identification of differentially expressed genes associated with the enhancement of X-ray susceptibility by RITA in a hypopharyngeal squamous cell carcinoma cell line (FaDu).

    Science.gov (United States)

    Luan, Jinwei; Li, Xianglan; Guo, Rutao; Liu, Shanshan; Luo, Hongyu; You, Qingshan

    2016-06-01

    Next generation sequencing and bio-informatic analyses were conducted to investigate the mechanism of reactivation of p53 and induction of tumor cell apoptosis (RITA)-enhancing X-ray susceptibility in FaDu cells. The cDNA was isolated from FaDu cells treated with 0 X-ray, 8 Gy X-ray, or 8 Gy X-ray + RITA. Then, cDNA libraries were created and sequenced using next generation sequencing, and each assay was repeated twice. Subsequently, differentially expressed genes (DEGs) were identified using Cuffdiff in Cufflinks and their functions were predicted by pathway enrichment analyses. Genes that were constantly up- or down-regulated in 8 Gy X-ray-treated FaDu cells and 8 Gy X-ray + RITA-treated FaDu cells were obtained as RITA genes. Afterward, the protein-protein interaction (PPI) relationships were obtained from the STRING database and a PPI network was constructed using Cytoscape. Furthermore, ClueGO was used for pathway enrichment analysis of genes in the PPI network. Total 2,040 and 297 DEGs were identified in FaDu cells treated with 8 Gy X-ray or 8 Gy X-ray + RITA, respectively. PARP3 and NEIL1 were enriched in base excision repair, and CDK1 was enriched in p53 signaling pathway. RFC2 and EZH2 were identified as RITA genes. In the PPI network, many interaction relationships were identified (e.g., RFC2-CDK1, EZH2-CDK1 and PARP3-EZH2). ClueGO analysis showed that RFC2 and EZH2 were related to cell cycle. RFC2, EZH2, CDK1, PARP3 and NEIL1 may be associated, and together enhance the susceptibility of FaDu cells treated with RITA to the deleterious effects of X-ray.

  6. Identification of differentially expressed genes associated with the enhancement of X-ray susceptibility by RITA in a hypopharyngeal squamous cell carcinoma cell line (FaDu)

    International Nuclear Information System (INIS)

    Luan, Jinwei; Li, Xianglan; Guo, Rutao; Liu, Shanshan; Luo, Hongyu; You, Qingshan

    2016-01-01

    Next generation sequencing and bio-informatic analyses were conducted to investigate the mechanism of reactivation of p53 and induction of tumor cell apoptosis (RITA)-enhancing X-ray susceptibility in FaDu cells. The cDNA was isolated from FaDu cells treated with 0 X-ray, 8 Gy X-ray, or 8 Gy X-ray + RITA. Then, cDNA libraries were created and sequenced using next generation sequencing, and each assay was repeated twice. Subsequently, differentially expressed genes (DEGs) were identified using Cuffdiff in Cufflinks and their functions were predicted by pathway enrichment analyses. Genes that were constantly up- or down-regulated in 8 Gy X-ray-treated FaDu cells and 8 Gy X-ray + RITA-treated FaDu cells were obtained as RITA genes. Afterward, the protein-protein interaction (PPI) relationships were obtained from the STRING database and a PPI network was constructed using Cytoscape. Furthermore, ClueGO was used for pathway enrichment analysis of genes in the PPI network. Total 2,040 and 297 DEGs were identified in FaDu cells treated with 8 Gy X-ray or 8 Gy X-ray + RITA, respectively. PARP3 and NEIL1 were enriched in base excision repair, and CDK1 was enriched in p53 signaling pathway. RFC2 and EZH2 were identified as RITA genes. In the PPI network, many interaction relationships were identified (e.g., RFC2-CDK1, EZH2-CDK1 and PARP3-EZH2). ClueGO analysis showed that RFC2 and EZH2 were related to cell cycle. RFC2, EZH2, CDK1, PARP3 and NEIL1 may be associated, and together enhance the susceptibility of FaDu cells treated with RITA to the deleterious effects of X-ray

  7. Test of the 'glymphatic' hypothesis demonstrates diffusive and aquaporin-4-independent solute transport in rodent brain parenchyma.

    Science.gov (United States)

    Smith, Alex J; Yao, Xiaoming; Dix, James A; Jin, Byung-Ju; Verkman, Alan S

    2017-08-21

    Transport of solutes through brain involves diffusion and convection. The importance of convective flow in the subarachnoid and paravascular spaces has long been recognized; a recently proposed 'glymphatic' clearance mechanism additionally suggests that aquaporin-4 (AQP4) water channels facilitate convective transport through brain parenchyma. Here, the major experimental underpinnings of the glymphatic mechanism were re-examined by measurements of solute movement in mouse brain following intracisternal or intraparenchymal solute injection. We found that: (i) transport of fluorescent dextrans in brain parenchyma depended on dextran size in a manner consistent with diffusive rather than convective transport; (ii) transport of dextrans in the parenchymal extracellular space, measured by 2-photon fluorescence recovery after photobleaching, was not affected just after cardiorespiratory arrest; and (iii) Aqp4 gene deletion did not impair transport of fluorescent solutes from sub-arachnoid space to brain in mice or rats. Our results do not support the proposed glymphatic mechanism of convective solute transport in brain parenchyma.

  8. Effects of 2'-chlorothymidine on Chinese hamster cells irradiated with x-rays and ultraviolet light

    Energy Technology Data Exchange (ETDEWEB)

    Murai, T; Kuwabara, M; Sato, F; Kubo, K; Itoh, T; Yoshii, G

    1985-06-01

    Effects of 2'-chlorothymidine (2'-Cl-TdR) and its mother compound, thymidine (TdR), on cell killing induced by X- and UV-irradiation have been investigated. Chinse hamster V-79 (TK/sup +/) cells as well as thymidine kinase deficient (TK/sup -/) variant cells, which were isolated from parental V-79 cells following stepwise treatment with BUdR, were incubated in a medium containing 2'-Cl-TdR and TdR after X- and UV-irradiation. In the TK/sup +/ cells, both 2'-Cl-TdR and TdR enhanced the killing efficiency of X-rays and ultraviolet light. On the other hand, in the TK/sup -/ cells, only 2'-Cl-TdR enhanced the killing efficiency of X- and UV-irradiation, and no effect of TdR was observed. These results suggest that phosphorylation of TdR by the enzyme is essential for its ability to modify radiation response, while the enhancement of cell killing by 2'-Cl-TdR must be explained by a mechanism at least partly independent of phosphorylation. (author).

  9. T2 relaxation time in MR imaging of normal and abnormal lung parenchyma

    International Nuclear Information System (INIS)

    Mayo, J.R.; McKay, A.; Mueller, N.L.

    1990-01-01

    To measure the T2 relaxation times of normal and abnormal lung parenchyma and to evaluate the influence of field strength and lung inflation on T2. Five healthy volunteers and five patients with diffuse lung disease were imaged at 0.15 and 1.5 T. Excised normal pig lung was imaged at 0.15 and 1.5 T and analyzed in a spectrometer at 2.0 T. Single-echo (Hahn) pulse sequences (TR, 2,000 msec; TE, 20, 40, 60, 80, and 100 msec) were compared with multiecho trains (Carr-Purcell-Meiboom-Gill [CPMG] at 0.15 T (TR, 2,000 msec; TE, 20-40-60... 240 msec) and 2.0 T (TR, 2,000 msec; TE, 1, 2, 3,..., 10msec). T2 relaxation times calculated from single-echo sequences showed considerable variation between 0.15 and 2.0 T. T2 also changed with lung inflation. However, the T2 measurements on CPMG sequences did not change significantly (P > .05) with field strength and were only minimally affected by lung inflation. The mean ± SD T2 values for normal lung were 99 ± 8 and for abnormal lung were 84 ± 17. Lung parenchyma T2 measurements obtained with the use of conventional single-echo pulse sequences are variable and inaccurate because of inflation and field strength dependent magnetic susceptibility effects that lead to rapid nonrecoverable dephasing. The results indicate that multiecho sequences with appropriately short echo spacings yield more reproducible determinations of T2, which are independent of field strength and less dependent on lung inflation

  10. Diffusion tensor imaging of spinal cord parenchyma lesion in rat with chronic spinal cord injury.

    Science.gov (United States)

    Zhao, Can; Rao, Jia-Sheng; Pei, Xiao-Jiao; Lei, Jian-Feng; Wang, Zhan-Jing; Zhao, Wen; Wei, Rui-Han; Yang, Zhao-Yang; Li, Xiao-Guang

    2018-04-01

    Adequate evaluation of spinal cord parenchyma and accurate identification of injury range are considered two premises for the research and treatment of chronic spinal cord injury (SCI). Diffusion tensor imaging (DTI) provides information about water diffusion in spinal cord, and thus makes it possible to realize these premises. In this study, we conducted magnetic resonance imaging (MRI) for Wistar rats 84days after spinal cord contusion. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) from different positions of the injured cord were collected, analyzed, and compared with the histological results and locomotor outcomes. Moreover, we performed fiber tractography, and examined the difference in cavity percentage obtained respectively via conventional MRI, DTI and histology. Results showed that the chronic SCI rats had the largest changes of all DTI metrics at the epicenter; the farther away from the epicenter, the smaller the variation. FA, AD and RD were all influenced by SCI in a greater space range than MD. The good consistency of FA values and histological results in specific regions evidenced FA's capability of reflecting Wallerian degeneration after SCI. DTI metrics at the epicenter in ventral funiculus also showed a close correlation with the BBB scores. Additionally, supported by the histological results, DTI enables a more accurate measurement of cavity percentage compared to the conventional MRI. DTI parameters might comprehensively reflect the post-SCI pathological status of spinal cord parenchyma at the epicenter and distal parts during the chronic stage, while showing good consistency with locomotor performance. DTI combined with tractography could intuitively display the distribution of spared fibers after SCI and accurately provide information such as cavity area. This may shed light on the research and treatment of chronic SCI. Copyright © 2017 Elsevier Inc. All rights

  11. Do protons and X-rays induce cell-killing in human peripheral blood lymphocytes by different mechanisms?

    Science.gov (United States)

    Miszczyk, J; Rawojć, K; Panek, A; Borkowska, A; Prasanna, P G S; Ahmed, M M; Swakoń, J; Gałaś, A

    2018-02-01

    Significant progress has been made in the technological and physical aspects of dose delivery and distribution in proton therapy. However, mode of cell killing induced by protons is less understood in comparison with X-rays. The purpose of this study is to see if there is any difference in the mode of cell-killing, induced by protons and X-rays in an ex vivo human peripheral blood lymphocyte (HPBL) model. HPBL were irradiated with 60 MeV proton beam or 250-kVp X-rays in the dose range of 0.3-4.0 Gy. Frequency of apoptotic and necrotic cells was determined by the Fluorescein (FITC)-Annexin V labelling procedure, 1 and 4 h after irradiation. Chip-based DNA Ladder Assay was used to confirm radiation-induced apoptosis and necrosis. Chip-based DNA Ladder Assay was used to confirm radiation-induced apoptosis. Ex vivo irradiation of HPBL with proton beams of 60 MeV or 250 kVp X-rays resulted in apoptotic as well as necrotic modes of cell-killing, which were evident at both 1 and 4 h after irradiation in the whole dose and time range. Generally, our results indicated that protons cause relatively higher yields of cell death that appears to be necrosis compared to X-rays. The analysis also demonstrates that radiation type and dose play a critical role in mode of cell-killing. Obtained results suggest that X-rays and protons induce cell-killing by different modes. Such differences in cell-killing modes may have implications on the potential of a given therapeutic modality to cause immune modulation via programmed cell death (X-rays) or necrotic cell death (proton therapy). These studies point towards exploring for gene expression biomarkers related necrosis or apoptosis to predict immune response after proton therapy.

  12. Sensitization by wortmannin of heat- or X-ray induced cell death in cultured Chinese hamster V79 cells

    International Nuclear Information System (INIS)

    Tomita, Masanori; Suzuki, Norio; Matsumoto, Yoshihisa; Hirano, Kazuya; Umeda, Noriko; Sakai, Kazuo

    2000-01-01

    Here we found that wortmannin sensitized Chinese hamster V79 cells to hyperthermic treatment at 44.0 deg C as determined either by colony formation assay or by dye exclusion assay. Wortmannin enhanced heat-induced cell death accompanying cleavage of poly (ADP-ribose) polymerases (PARP). Additionally, the induction of heat shock protein HSP70 was suppressed and delayed in wortmannin-treated cells. Heat sensitizing effect of wortmannin was obvious at more than 5 or 10 μM of final concentrations, while radiosensitization was apparent at 5 μM. Requirement for high concentration of wortmannin, i.e., order of μM, suggests a possible role of certain protein kinases, such as DNA-PK and/or ATM among PI3-kinase family. The sensitization was minimal when wortmannin was added at the end of heat treatment. This was similar to the case of X-ray. Since heat-induced cell death and PARP cleavage preceded HSP70 induction phenomenon, the sensitization to the hyperthermic treatment was considered mainly caused by enhanced apoptotic cell death rather than secondary to suppression or delay by wortmannin of HSP70 induction. Further, in the present system radiosensitization by wortmannin was also at least partly mediated through enhancement of apoptotic cell death. (author)

  13. X-ray induced translocations in premeiotic germ cells of monkeys

    International Nuclear Information System (INIS)

    Buul, P.P.W. van

    1991-01-01

    Induction of reciprocal translocations by various X-ray exposures was studied in spermatogonial stem cells of rhesus monkeys (Macaca mulatta) and stump-tailed Macaques (arctoides) by means of spermatocyte analysis many cell generations after irradiation. The yields of trans-locations recovered from irradiated stump-tailed macaques were lower than those observed in rhesus monkeys and represent in fact the lowest induction rates per Gy ever recorded for experimental mammals. In the rhesus monkey a humped dose-effect relationship was found with 1.a homo -geneous response with (pseudo-)linear kinetics below 1 Gy, 2.much more variability at higher doses, and 3.no induction at all at doses of 4 Gy and above. It is suggested that the post-irradiation proliferation differentiation pattern of surviving rhesus monkey spermatogonial stem cells is mainly responsible for these characteristics of the dose-response curve. (author). 41 refs.; 1 fig.; 4 tabs

  14. Effects of 60Co gamma-rays on some biological characteristics of Chinese hamster lung cells

    International Nuclear Information System (INIS)

    Tang Pei; Wang Shoufang; Zhang Shuxian

    1988-01-01

    The proliferation of cells and the relationship between survival and dose were investigated in Chinese hamster lung (CHL) cells grown at stationary phase and irradiated with 60 Co gamma-rays. The ultrastructural changes and chromosome aberration in the cells after irradiation were also observed. The frequency of chromosome aberrations increased linearly with dose and the yields of dicentrics plus rings were best fitted to a linear-quadratic model. The 50% growth-inhibited dose was found to be 4.0Gy. Electron microscopy observation revealed swelling and vacuolation of mitochodria and indistinct cristae at lower doses. The alterations in nucleus at higher doses appeared to be depression of nuclear membrane and disappearance of chromatin

  15. A leukocyte antigen, Leu-13, is involved in induction of resistance of human cells to x-ray cell killing by interferon-α

    International Nuclear Information System (INIS)

    Kita, Kazuko; Zhai, Ling; Sugaya, Shigeru; Suzuki, Nobuo

    2003-01-01

    We previously reported on human interferon (HuIFN)-induced resistance of human cells to X-ray and UV cell killing. In this study, we searched for the genes whose expression is responsible for the resistance, using a PCR-based mRNA differential display method and Northern blotting analysis. RSa cells were used for this analysis, because they show increased resistance to X-ray- and UV-caused cell killing by HuIFN-α treatment prior to irradiation. Messenger RNA expression levels for Leu-13, a leukocyte antigen, were markedly up-regulated in RSa cells after HuIFN-α treatment. Furthermore, pretreatment of RSa cells with antisense oligonucleotides for Leu-13 mRNA resulted in the suppression of the HuIFN-α-induced resistance of the cells to X-ray cell killing, but did not modulate HuIFN-α-induced resistance to UV cell killing. These results suggest that Leu-13 is involved in HuIFN-α-induced resistance of human cells to X-ray cell killing, but not to UV cell killing. (author)

  16. Automated high pressure cell for pressure jump x-ray diffraction.

    Science.gov (United States)

    Brooks, Nicholas J; Gauthe, Beatrice L L E; Terrill, Nick J; Rogers, Sarah E; Templer, Richard H; Ces, Oscar; Seddon, John M

    2010-06-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  17. Inactivation and mutation of cultured mammalian cells by aluminium characteristic ultrasoft X-rays

    International Nuclear Information System (INIS)

    Goodhead, D.T.

    1977-01-01

    Microdosimetric distributions for aluminium K characteristic ultrasoft X-rays and 4 He ion track intersections have been calculated and used to analyse recent biological results obtained with these radiations. Results on inactivation and mutation-induction to thioguanine resistance of both V79 Chinese hamster cells and HF19 human diploid fibroblasts in vitro were analysed in terms of the Kellerer-Rossi 'theory of dual radiation action'. The small quantum energy of the aluminium X-ray photons and the very short length of the secondary electrons which they produce highlight the inadequacy of the model. It has been shown that the model predicted r.b.e. values in conflict with those observed unless an additional variable was introduced, but that the introduction of such a variable created mathematical inconsistencies. The experimental evidence is contrary to the conventional usage and basis of the model. (author)

  18. Automated high pressure cell for pressure jump x-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M. [Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Terrill, Nick J. [Diamond Light Source, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0DE (United Kingdom); Rogers, Sarah E. [ISIS, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, Didcot, Oxfordshire OX11 0QX (United Kingdom)

    2010-06-15

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  19. Automated high pressure cell for pressure jump x-ray diffraction

    International Nuclear Information System (INIS)

    Brooks, Nicholas J.; Gauthe, Beatrice L. L. E.; Templer, Richard H.; Ces, Oscar; Seddon, John M.; Terrill, Nick J.; Rogers, Sarah E.

    2010-01-01

    A high pressure cell for small and wide-angle x-ray diffraction measurements of soft condensed matter samples has been developed, incorporating a fully automated pressure generating network. The system allows both static and pressure jump measurements in the range of 0.1-500 MPa. Pressure jumps can be performed as quickly as 5 ms, both with increasing and decreasing pressures. Pressure is generated by a motorized high pressure pump, and the system is controlled remotely via a graphical user interface to allow operation by a broad user base, many of whom may have little previous experience of high pressure technology. Samples are loaded through a dedicated port allowing the x-ray windows to remain in place throughout an experiment; this facilitates accurate subtraction of background scattering. The system has been designed specifically for use at beamline I22 at the Diamond Light Source, United Kingdom, and has been fully integrated with the I22 beamline control systems.

  20. Cell-free protein synthesis for structure determination by X-ray crystallography.

    Science.gov (United States)

    Watanabe, Miki; Miyazono, Ken-ichi; Tanokura, Masaru; Sawasaki, Tatsuya; Endo, Yaeta; Kobayashi, Ichizo

    2010-01-01

    Structure determination has been difficult for those proteins that are toxic to the cells and cannot be prepared in a large amount in vivo. These proteins, even when biologically very interesting, tend to be left uncharacterized in the structural genomics projects. Their cell-free synthesis can bypass the toxicity problem. Among the various cell-free systems, the wheat-germ-based system is of special interest due to the following points: (1) Because the gene is placed under a plant translational signal, its toxic expression in a bacterial host is reduced. (2) It has only little codon preference and, especially, little discrimination between methionine and selenomethionine (SeMet), which allows easy preparation of selenomethionylated proteins for crystal structure determination by SAD and MAD methods. (3) Translation is uncoupled from transcription, so that the toxicity of the translation product on DNA and its transcription, if any, can be bypassed. We have shown that the wheat-germ-based cell-free protein synthesis is useful for X-ray crystallography of one of the 4-bp cutter restriction enzymes, which are expected to be very toxic to all forms of cells retaining the genome. Our report on its structure represents the first report of structure determination by X-ray crystallography using protein overexpressed with the wheat-germ-based cell-free protein expression system. This will be a method of choice for cytotoxic proteins when its cost is not a problem. Its use will become popular when the crystal structure determination technology has evolved to require only a tiny amount of protein.

  1. Synchrotron X-ray fluorescence studies of a bromine-labelled cyclic RGD peptide interacting with individual tumor cells

    International Nuclear Information System (INIS)

    Sheridan, Erin J.; Austin, Christopher J. D.; Aitken, Jade B.; Vogt, Stefan; Jolliffe, Katrina A.; Harris, Hugh H.; Rendina, Louis M.

    2013-01-01

    The first example of synchrotron X-ray fluorescence imaging of cultured mammalian cells in cyclic peptide research is reported. The study reports the first quantitative analysis of the incorporation of a bromine-labelled cyclic RGD peptide and its effects on the biodistribution of endogenous elements (for example, K and Cl) within individual tumor cells. The first example of synchrotron X-ray fluorescence imaging of cultured mammalian cells in cyclic peptide research is reported. The study reports the first quantitative analysis of the incorporation of a bromine-labelled cyclic RGD peptide and its effects on the biodistribution of endogenous elements (for example, K and Cl) within individual tumor cells

  2. Enhanced lethal effect of combined ACNU with x-ray on cultured HeLaS3 cells

    International Nuclear Information System (INIS)

    Kanazawa, Haruyuki; Miyamoto, Tadaaki

    1983-01-01

    The combined effects of ACNU and X-irradiation on cultured HeLaS 3 cells were investigated. Pretreatment with either ACNU or X-ray induced a substantial reduction in shoulder width the D 0 value of the dose-response curve for the other agent, given later was unchanged. ACNU did not inhibit the recovery of sublethal damage (SLD) induced by X-ray when this treatment preceded the spilit-dose experiment. Our results indicate that some cell damage induced by each agent is transmissible to the progeny of the surviving cells and that the interaction of ACNU and X-irradiation was lethal to the cells. (author)

  3. Down-regulation of SMT3A gene expression in association with DNA synthesis induction after X-ray irradiation in nevoid basal cell carcinoma syndrome (NBCCS) cells

    International Nuclear Information System (INIS)

    Sugaya, Shigeru; Nakanishi, Hiroshi; Tanzawa, Hideki; Sugita, Katsuo; Kita, Kazuko; Suzuki, Nobuo

    2005-01-01

    Fibroblast cells derived from nevoid basal carcinoma syndrome (NBCCS) patients show increased levels of DNA synthesis after X-ray irradiation. Genes, whose expression is modulated in association with the DNA synthesis induction, were searched by using PCR-based mRNA differential display analysis in one of the NBCCS cell lines, NBCCS1 cells. Decreased levels of SMT3A gene expression were found in X-ray-irradiated NBCCS1 cells. This decrease was also shown by RT-PCR analysis in another cell line, NBCCS3 cells. In addition to NBCCS cells, normal fibroblast cells showed the DNA synthesis induction after X-ray irradiation when they were treated with antisense oligonucleotides (AO) for SMT3A. However, treatment of normal fibroblasts with the random oligonucleotides (RO) resulted in decreased levels of DNA synthesis after X-ray irradiation. Thus, down-regulation of SMT3A gene expression may be involved in the DNA synthesis induction after X-ray irradiation in the NBCCS cells at least tested

  4. Down-regulation of SMT3A gene expression in association with DNA synthesis induction after X-ray irradiation in nevoid basal cell carcinoma syndrome (NBCCS) cells

    Energy Technology Data Exchange (ETDEWEB)

    Sugaya, Shigeru [Department of Environmental Biochemistry, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Nakanishi, Hiroshi [Department of Clinical Molecular Biology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Tanzawa, Hideki [Department of Clinical Molecular Biology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Sugita, Katsuo [Department of Clinical Medicine, Faculty of Education, Chiba University, 1-33 Yayoi, Inage-ku, Chiba 263-8522 (Japan); Kita, Kazuko [Department of Environmental Biochemistry, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan); Suzuki, Nobuo [Department of Environmental Biochemistry, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670 (Japan)]. E-mail: nobuo@faculty.chiba-u.jp

    2005-10-15

    Fibroblast cells derived from nevoid basal carcinoma syndrome (NBCCS) patients show increased levels of DNA synthesis after X-ray irradiation. Genes, whose expression is modulated in association with the DNA synthesis induction, were searched by using PCR-based mRNA differential display analysis in one of the NBCCS cell lines, NBCCS1 cells. Decreased levels of SMT3A gene expression were found in X-ray-irradiated NBCCS1 cells. This decrease was also shown by RT-PCR analysis in another cell line, NBCCS3 cells. In addition to NBCCS cells, normal fibroblast cells showed the DNA synthesis induction after X-ray irradiation when they were treated with antisense oligonucleotides (AO) for SMT3A. However, treatment of normal fibroblasts with the random oligonucleotides (RO) resulted in decreased levels of DNA synthesis after X-ray irradiation. Thus, down-regulation of SMT3A gene expression may be involved in the DNA synthesis induction after X-ray irradiation in the NBCCS cells at least tested.

  5. Irradiating cell samples in an x-ray radiation cabinet-the effect of tube filtration

    International Nuclear Information System (INIS)

    Parkin, Adrian; Wright, Ian; Yates, Stuart; Goldstone, Karen E; Russell, Paul; Starr, Christy

    2004-01-01

    The cell irradiation cabinet described is used for creating DNA damage in cell samples in order to study tumourigenesis. The medical research laboratory involved was using the manufacturer's quoted dose rate (32.2 mGy s -1 ) to determine the required exposure time to impart a dose of 10 Gy. The x-ray output was investigated when the exposure failed to produce cell cycle arrest. The x-ray tube was fitted with only a 0.76 mm beryllium filter, and the spectrum therefore contained a high proportion of low energy photons which were being removed by the polystyrene sample flask as demonstrated by dose measurements in air and through the sample flask. Incorporation of a 0.5 mm aluminium filter removed most of these low energy photons but greatly reduced the dose rate to 3.8 mGy s -1 . The manufacturer's quoted dose rates from a lightly filtered tube are misleading: the contribution of the very low energy component of the spectrum to the dose is not relevant since it will be removed by a sample flask. (note)

  6. Carbon-ion beam irradiation kills X-ray-resistant p53-null cancer cells by inducing mitotic catastrophe.

    Directory of Open Access Journals (Sweden)

    Napapat Amornwichet

    Full Text Available BACKGROUND AND PURPOSE: To understand the mechanisms involved in the strong killing effect of carbon-ion beam irradiation on cancer cells with TP53 tumor suppressor gene deficiencies. MATERIALS AND METHODS: DNA damage responses after carbon-ion beam or X-ray irradiation in isogenic HCT116 colorectal cancer cell lines with and without TP53 (p53+/+ and p53-/-, respectively were analyzed as follows: cell survival by clonogenic assay, cell death modes by morphologic observation of DAPI-stained nuclei, DNA double-strand breaks (DSBs by immunostaining of phosphorylated H2AX (γH2AX, and cell cycle by flow cytometry and immunostaining of Ser10-phosphorylated histone H3. RESULTS: The p53-/- cells were more resistant than the p53+/+ cells to X-ray irradiation, while the sensitivities of the p53+/+ and p53-/- cells to carbon-ion beam irradiation were comparable. X-ray and carbon-ion beam irradiations predominantly induced apoptosis of the p53+/+ cells but not the p53-/- cells. In the p53-/- cells, carbon-ion beam irradiation, but not X-ray irradiation, markedly induced mitotic catastrophe that was associated with premature mitotic entry with harboring long-retained DSBs at 24 h post-irradiation. CONCLUSIONS: Efficient induction of mitotic catastrophe in apoptosis-resistant p53-deficient cells implies a strong cancer cell-killing effect of carbon-ion beam irradiation that is independent of the p53 status, suggesting its biological advantage over X-ray treatment.

  7. Measurements of accurate x-ray scattering data of protein solutions using small stationary sample cells

    Science.gov (United States)

    Hong, Xinguo; Hao, Quan

    2009-01-01

    In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage induced by intense synchrotron radiation sources is indispensable for the correct interpretation of scattering data, there is still a lack of effective methods to overcome radiation-induced aggregation and extract scattering profiles free from chemical or structural damage. It is found that radiation-induced aggregation mainly begins on the surface of the sample cell and grows along the beam path; the diameter of the damaged region is comparable to the x-ray beam size. Radiation-induced aggregation can be effectively avoided by using a two-dimensional scan (2D mode), with an interval as small as 1.5 times the beam size, at low temperature (e.g., 4 °C). A radiation sensitive protein, bovine hemoglobin, was used to test the method. A standard deviation of less than 5% in the small angle region was observed from a series of nine spectra recorded in 2D mode, in contrast to the intensity variation seen using the conventional stationary technique, which can exceed 100%. Wide-angle x-ray scattering data were collected at a standard macromolecular diffraction station using the same data collection protocol and showed a good signal/noise ratio (better than the reported data on the same protein using a flow cell). The results indicate that this method is an effective approach for obtaining precise measurements of protein solution scattering.

  8. Measurements of accurate x-ray scattering data of protein solutions using small stationary sample cells

    International Nuclear Information System (INIS)

    Hong Xinguo; Hao Quan

    2009-01-01

    In this paper, we report a method of precise in situ x-ray scattering measurements on protein solutions using small stationary sample cells. Although reduction in the radiation damage induced by intense synchrotron radiation sources is indispensable for the correct interpretation of scattering data, there is still a lack of effective methods to overcome radiation-induced aggregation and extract scattering profiles free from chemical or structural damage. It is found that radiation-induced aggregation mainly begins on the surface of the sample cell and grows along the beam path; the diameter of the damaged region is comparable to the x-ray beam size. Radiation-induced aggregation can be effectively avoided by using a two-dimensional scan (2D mode), with an interval as small as 1.5 times the beam size, at low temperature (e.g., 4 deg. C). A radiation sensitive protein, bovine hemoglobin, was used to test the method. A standard deviation of less than 5% in the small angle region was observed from a series of nine spectra recorded in 2D mode, in contrast to the intensity variation seen using the conventional stationary technique, which can exceed 100%. Wide-angle x-ray scattering data were collected at a standard macromolecular diffraction station using the same data collection protocol and showed a good signal/noise ratio (better than the reported data on the same protein using a flow cell). The results indicate that this method is an effective approach for obtaining precise measurements of protein solution scattering.

  9. Analysis of X-ray induced cell-cycle perturbations in mouse osteosarcoma cells: a two-signal cell-cycle model

    International Nuclear Information System (INIS)

    Meeteren, A. van; Wijk, R. van; Stap, J.; Deys, B.F.

    1984-01-01

    The effects of X-irradiation on mouse osteosarcoma cells have been studied by time-lapse cinematography and the resulting pedigrees have been analysed statistically. It is shown that the irradiation treatment causes three types of cell kinetic lesions: cell death (disintegration), cell sterilization (failure to divide) and proliferation delay. The first two lesions are the most important with regard to survival of the irradiated cell in a clonal assay. Of these two lesions, sterilization appears to be highly correlated for sister cells, while this is not true for cell disintegration. This indicates that cell survival in a clonal assay may be a function of the ratio of the incidences of these two types of lesions. The X-ray-induced proliferation delay was studied in terms of intermitotic time distributions, mother-daughter correlation and sibling correlation in relation to the current cell-cycle phase at the time of treatment. This analysis shows that the effects of irradiation on these cell-cycle characteristics is highly cell-cycle-dependent. A qualitative model to account for the observations is presented. (author)

  10. Analysis of X-ray induced cell-cycle perturbations in mouse osteosarcoma cells: a two-signal cell-cycle model

    Energy Technology Data Exchange (ETDEWEB)

    Meeteren, A van; Wijk, R van [Rijksuniversiteit Utrecht (Netherlands); Stap, J; Deys, B F [Amsterdam Univ. (Netherlands)

    1984-03-01

    The effects of X-irradiation on mouse osteosarcoma cells have been studied by time-lapse cinematography and the resulting pedigrees have been analysed statistically. It is shown that the irradiation treatment causes three types of cell kinetic lesions: cell death (disintegration), cell sterilization (failure to divide) and proliferation delay. The first two lesions are the most important with regard to survival of the irradiated cell in a clonal assay. Of these two lesions, sterilization appears to be highly correlated for sister cells, while this is not true for cell disintegration. This indicates that cell survival in a clonal assay may be a function of the ratio of the incidences of these two types of lesions. The X-ray-induced proliferation delay was studied in terms of intermitotic time distributions, mother-daughter correlation and sibling correlation in relation to the current cell-cycle phase at the time of treatment. This analysis shows that the effects of irradiation on these cell-cycle characteristics is highly cell-cycle-dependent. A qualitative model to account for the observations is presented.

  11. Ataxia telangiectasia derived iPS cells show preserved x-ray sensitivity and decreased chromosomal instability

    OpenAIRE

    Fukawatase, Yoshihiro; Toyoda, Masashi; Okamura, Kohji; Nakamura, Ken-ichi; Nakabayashi, Kazuhiko; Takada, Shuji; Yamazaki-Inoue, Mayu; Masuda, Akira; Nasu, Michiyo; Hata, Kenichiro; Hanaoka, Kazunori; Higuchi, Akon; Takubo, Kaiyo; Umezawa, Akihiro

    2014-01-01

    Ataxia telangiectasia is a neurodegenerative inherited disease with chromosomal instability and hypersensitivity to ionizing radiation. iPS cells lacking ATM (AT-iPS cells) exhibited hypersensitivity to X-ray irradiation, one of the characteristics of the disease. While parental ataxia telangiectasia cells exhibited significant chromosomal abnormalities, AT-iPS cells did not show any chromosomal instability in vitro for at least 80 passages (560 days). Whole exome analysis also showed a compa...

  12. Aloe vera phenomenon: a review of the properties and modern uses of the leaf parenchyma gel

    Energy Technology Data Exchange (ETDEWEB)

    Grindlay, D.; Reynolds, T.

    1986-06-01

    The mucilaginous gel from the parenchymatous cells in the leaf pulp of Aloe vera has been used since early times for a host of curative purposes. This gel should be distinguished clearly from the bitter yellow exudate originating from the bundle sheath cells, which is used for its purgative effects. Aloe vera gel has come to play a prominent role as a contemporary folk remedy, and numerous optimistic, and in some cases extravagant, claims have been made for its medicinal properties. Modern clinical use of the gel began in the 1930s, with reports of successful treatment of X-ray and radium burns, which led to further experimental studies using laboratory animals in the following decades. The reports of these experiments and the numerous favourable case histories did not give conclusive evidence, since although positive results were usually described, much of the work suffered from poor experimental design and insufficiently large test samples. In addition some conflicting or inconsistent results were obtained. With the recent resurgence of interest in Aloe vera gel, however, new experimental work has indicated the possibility of distinct physiological effects. Chemical analysis has shown the gel to contain various carbohydrate polymers, notably either glucomannans or pectic acid, along with a range of other organic and inorganic components. Although many physiological properties of the gel have been described, there is no certain correlation between these and the identified gel components. 154 references.

  13. Correlative cryogenic tomography of cells using light and soft x-rays

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Elizabeth A.; Cinquin, Bertrand P.; Do, Myan; McDermott, Gerry [Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA (United States); National Center for X-ray Tomography, Advanced Light Source, Berkeley, CA (United States); Le Gros, Mark A., E-mail: MALegros@lbl.gov [Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA (United States); Physical BioSciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); National Center for X-ray Tomography, Advanced Light Source, Berkeley, CA (United States); Larabell, Carolyn A., E-mail: carolyn.larabell@ucsf.edu [Department of Anatomy, School of Medicine, University of California San Francisco, San Francisco, CA (United States); Physical BioSciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); National Center for X-ray Tomography, Advanced Light Source, Berkeley, CA (United States)

    2014-08-01

    Correlated imaging is the process of imaging a specimen with two complementary modalities, and then combining the two data sets to create a highly informative, composite view. A recent implementation of this concept has been the combination of soft x-ray tomography (SXT) with fluorescence cryogenic microscopy (FCM). SXT–FCM is used to visualize cells that are held in a near-native, cryopreserved. The resultant images are, therefore, highly representative of both the cellular architecture and molecular organization in vivo. SXT quantitatively visualizes the cell and sub-cellular structures; FCM images the spatial distribution of fluorescently labeled molecules. Here, we review the characteristics of SXT–FCM, and briefly discuss how this method compares with existing correlative imaging techniques. We also describe how the incorporation of a cryo-rotation stage into a cryogenic fluorescence microscope allows acquisition of fluorescence cryogenic tomography (FCT) data. FCT is optimally suited for correlation with SXT, since both techniques image the specimen in 3-D, potentially with similar, isotropic spatial resolution. - Highlights: • We describe a new correlated imaging modality: soft x-ray tomography combined (SXT) with confocal fluorescence tomography (CFT). • Data from the two modalities are combined accurately and precisely using fiducials visible in both types of data. • Cells imaged by SXT–CFT are maintained close to their native state by cryo-preservation. • SXT–CFT is applicable to most cell types, especially cells grown in suspension. • ‘Super-resolution’ microscopes being developed for CFT data acquisition match the spatial resolution of SXT.

  14. Focusing of megaampere electron beam in gas cell for production of flash X-ray source

    Energy Technology Data Exchange (ETDEWEB)

    Zinchenko, Vl; Chlenov, A M; Shiyan, V D [Research Institute of Scientific Instruments, Turaevo-Lytkarino (Russian Federation)

    1997-12-31

    One of important problems to be solved in the development of an intense source of flash X-rays is the choice of the optimum design of the high-current diode at the exit of the electron accelerator. The results of numerical investigations of megaampere relativistic electron beam (REB) generation and focusing in a compound diode are discussed. The diode consists of a vacuum field-emission annular cathode, a planar anode, and a gas cell inserted between the anode foil and the target. (author). 2 figs., 5 refs.

  15. Interchromosomal distribution of gamma ray-induced chromatid aberrations in Chinese hamster ovary cells

    International Nuclear Information System (INIS)

    Martinez-Lopez, Wilner; Porro, Valentina; Folle, Gustavo A.; Mendez-Acuna, Leticia; Obe, Guenter; Savage, John R.K.

    2000-01-01

    Inter chromosomal distributions of breakpoints from chromatid-type aberrations induced by gamma rays in Chinese hamster ovary cells were analyzed. In most chromosomes the distribution was as expected from chromosome lengths for simple breaks or the respective relative corrected length in case of exchanges. There were deviations from expectation in a few chromosomes for chromatid breaks, interchanges, intra-arm intra changes and inter-arm intra changes. Especially interesting are the results concerning chromosomes 2 and 8, which were more often involved in exchanges than expected. An 'exchange phenotype' for these chromosomes is proposed and possible explanations for the nonrandom distribution of chromosome breakpoints are presented. (author)

  16. Study on method of characteristics based on cell modular ray tracing

    International Nuclear Information System (INIS)

    Tang Chuntao; Zhang Shaohong

    2009-01-01

    To address the issue of accurately solving neutron transport problem in complex geometry, method of characteristics (MOC) is studied in this paper, and a quite effective and memory saving cell modular ray tracing (CMRT) method is developed and related angle discretization and boundary condition handling issues are discussed. A CMRT based MOC code-PEACH is developed and tested against C5G7 MOX benchmark problem. Numerical results demonstrate that PEACH can give excellent accuracy for both k eff and pin power distribution for neutron transport problem. (authors)

  17. Induction of micronuclei in the root tip cells of Haplopappus germinating seeds by fission neutrons and X rays

    International Nuclear Information System (INIS)

    Hanmoto, Hidehiro; Yonezawa, Yoshihiko; Itoh, Tetsuo; Kondo, Sohei.

    1992-01-01

    Seeds of Haplopappus gracilis (2n=4), an annual Compositae, were soaked in water for 24 hr and then irradiated with fission neutrons from the 1-wattage reactor, UTR-KINKI, or X rays. The root tip cells were inspected at 48 hr post-irradiation for evidence of chromosome damage using micronucleus as endpoint. The frequency of neutron-induced micronuclei increased almost linearly as the dose increased up to as much as 1.2 Gy. X-ray-induced micronuclei showed an exponential dose-response relation. From dose-response data, we estimated that the dose necessary to induce micronuclei at a frequency of 5 per 1,000 cells was 1.2 Gy for neutrons and 8.6 Gy for X rays. Thus, to induce chromosome damage in the somatic cells of germinating Haplopappus seeds, fission neutrons were much more effective than X rays. (author)

  18. Relationship between X-ray exposure and malignant transformation in C3H 10T1/2 cells

    International Nuclear Information System (INIS)

    Kennedy, A.R.; Fox, M.; Murphy, G.; Little, J.B.

    1980-01-01

    The appearance of transformed foci after x-irradiation of the C3H 10T1/2 line of murine cells requires extensive proliferation followed by prolonged incubation under conditions of confluence. When the progeny of irradiated cells are resuspended and plated to determine the number of potential transformed foci, the absolute yield is constant over a wide range of dilutions and is similar to that observed in cultures that have not been resuspended. In addition, for cells exposed to a given x-ray dose, the number of transformed foci per dish is independent of the number of irradiated cells. These observations suggest that few, if any, of the transformed clones occur as a direct consequence of the x-ray exposure and challenge the hypothesis that transformed foci are the clonal products of occasional cells that have experienced an x-ray-induced mutational change. Rather, it appears that at least two steps are involved. We suggest that exposure to x-rays results in a change, for example, the induction or expression of some cell function, in many or all of the cells and that this change is transmitted to the progeny of the surviving cells; a consequence of this change is an enhanced probability of the occurrence of a second step, transformation, when these cells are maintained under conditions of confluence

  19. Response of mesenchymal stem cells in mice to 3.5 Gy X-ray irradiation

    International Nuclear Information System (INIS)

    Su Wenxia; Liu Huimin; Chen Yonghong; Zeng Wen; Liu Wenli; Sun Hanying

    2011-01-01

    Objective: To investigate the response of mesenchymal stem cells in mice to medium-dose X-ray irradiation in vitro. Methods: The mouse mesenchymal stem cell line C3H10T1/2 was submitted to 3.5 Gy X-ray irradiation. Hoechst33258 staining of adherent cells and Annexin V-FITC staining and flow cytometry analysis of suspension cells were performed respectively to assess cellular apoptosis at 3, 6, 12, 24, 48, 72 h and 1 week after irradiation. SA-β-gal staining was performed to analyze the cellular senescence at 24, 48, 72 h and 1 week after irradiation. The mRNA level of both Fas with its ligand FasL and p53 with its downstream target p21 WAF1 were measured by Real-Time PCR analysis. The expression of Fas protein was determined by immunofluorescence staining. Results: An increased apoptosis was observed at 3 h after irradiation with apoptosis rate 11.72% ± 1.61% (t=9.01, P<0.01), the apoptosis rate reached the peak level at 12 h 20.52% ± 1.96% (t=16.27, P<0.01), and then declined progressively to normal level at 48 h 4.93% ±0.46% (t=2.26, P>0.05). The SA-β-gal positive rate of post-radiation cells at 72 h was 53.33% ± 5.62%, significantly higher than that of normal control 3.24% ± 0.39% (t=17.77, P<0.01). The level of Fas, FasL mRNA was found to be elevated 3 h after irradiation with a peak at 12 h, and no differences were found l week later. The level of Fas protein was observed to reach the peak at 12 h after irradiation. The occurrence of peak level of Fas/FasL mRNA and protein was consistent with that of apoptosis of C3H10T1/2 cell. A transient up-regulation of p53, p21 WAF1 mRNA expression was found at 12 h after irradiation followed by a significant increase later at 72 h after irradiation. The occurrence of the two peaks of p53, p21 WAF1 mRNA expression were coincident with that of cellular apoptosis and senescence, respectively. The levels of p53, p21 WAF1 mRNA in senescence group were significantly higher than those of apoptosis group (t=17.85, 13

  20. Targeting transferrin receptors at the blood-brain barrier improves the uptake of immunoliposomes and subsequent cargo transport into the brain parenchyma

    DEFF Research Database (Denmark)

    Johnsen, Kasper B.; Burkhart, Annette; Melander, Fredrik

    2017-01-01

    Drug delivery to the brain is hampered by the presence of the blood-brain barrier, which excludes most molecules from freely diffusing into the brain, and tightly regulates the active transport mechanisms that ensure sufficient delivery of nutrients to the brain parenchyma. Harnessing...... the possibility of delivering neuroactive drugs by way of receptors already present on the brain endothelium has been of interest for many years. The transferrin receptor is of special interest since its expression is limited to the endothelium of the brain as opposed to peripheral endothelium. Here, we...... investigate the possibility of delivering immunoliposomes and their encapsulated cargo to the brain via targeting of the transferrin receptor. We find that transferrin receptor-targeting increases the association between the immunoliposomes and primary endothelial cells in vitro, but that this does...

  1. Targeting transferrin receptors at the blood-brain barrier improves the uptake of immunoliposomes and subsequent cargo transport into the brain parenchyma

    DEFF Research Database (Denmark)

    Johnsen, Kasper B.; Burkhart, Annette; Melander, Fredrik

    2017-01-01

    Drug delivery to the brain is hampered by the presence of the blood-brain barrier, which excludes most molecules from freely diffusing into the brain, and tightly regulates the active transport mechanisms that ensure sufficient delivery of nutrients to the brain parenchyma. Harnessing the possibi...... cargo uptake in the brain endothelium and subsequent cargo transport into the brain. These findings suggest that transferrin receptor-targeting is a relevant strategy of increasing drug exposure to the brain....... investigate the possibility of delivering immunoliposomes and their encapsulated cargo to the brain via targeting of the transferrin receptor. We find that transferrin receptor-targeting increases the association between the immunoliposomes and primary endothelial cells in vitro, but that this does...... not correlate with increased cargo transcytosis. Furthermore, we show that the transferrin receptor-targeted immunoliposomes accumulate along the microvessels of the brains of rats, but find no evidence for transcytosis of the immunoliposome. Conversely, the increased accumulation correlated both with increased...

  2. Differential effects of x-rays and high-energy 56Fe ions on human mesenchymal stem cells.

    Science.gov (United States)

    Kurpinski, Kyle; Jang, Deok-Jin; Bhattacharya, Sanchita; Rydberg, Bjorn; Chu, Julia; So, Joanna; Wyrobek, Andy; Li, Song; Wang, Daojing

    2009-03-01

    Stem cells hold great potential for regenerative medicine, but they have also been implicated in cancer and aging. How different kinds of ionizing radiation affect stem cell biology remains unexplored. This study was designed to compare the biological effects of X-rays and of high-linear energy transfer (LET) (56)Fe ions on human mesenchymal stem cells (hMSC). A multi-functional comparison was carried out to investigate the differential effects of X-rays and (56)Fe ions on hMSC. The end points included modulation of key markers such as p53, cell cycle progression, osteogenic differentiation, and pathway and networks through transcriptomic profiling and bioinformatics analysis. X-rays and (56)Fe ions differentially inhibited the cell cycle progression of hMSC in a p53-dependent manner without impairing their in vitro osteogenic differentiation process. Pathway and network analyses revealed that cytoskeleton and receptor signaling were uniquely enriched for low-dose (0.1 Gy) X-rays. In contrast, DNA/RNA metabolism and cell cycle regulation were enriched for high-dose (1 Gy) X-rays and (56)Fe ions, with more significant effects from (56)Fe ions. Specifically, DNA replication, DNA strand elongation, and DNA binding/transferase activity were perturbed more severely by 1 Gy (56)Fe ions than by 1 Gy X-rays, consistent with the significant G2/M arrest for the former while not for the latter. (56)Fe ions exert more significant effects on hMSC than X-rays. Since hMSC are the progenitors of osteoblasts in vivo, this study provides new mechanistic understandings of the relative health risks associated with low- and high-dose X-rays and high-LET space radiation.

  3. Differential Effects of X-Rays and High-Energy 56Fe Ions on Human Mesenchymal Stem Cells

    International Nuclear Information System (INIS)

    Kurpinski, Kyle; Jang, Deok-Jin; Bhattacharya, Sanchita; Rydberg, Bjorn; Chu, Julia; So, Joanna; Wyrobek, Andy; Li Song; Wang Daojing

    2009-01-01

    Purpose: Stem cells hold great potential for regenerative medicine, but they have also been implicated in cancer and aging. How different kinds of ionizing radiation affect stem cell biology remains unexplored. This study was designed to compare the biological effects of X-rays and of high-linear energy transfer (LET) 56 Fe ions on human mesenchymal stem cells (hMSC). Methods and Materials: A multi-functional comparison was carried out to investigate the differential effects of X-rays and 56 Fe ions on hMSC. The end points included modulation of key markers such as p53, cell cycle progression, osteogenic differentiation, and pathway and networks through transcriptomic profiling and bioinformatics analysis. Results: X-rays and 56 Fe ions differentially inhibited the cell cycle progression of hMSC in a p53-dependent manner without impairing their in vitro osteogenic differentiation process. Pathway and network analyses revealed that cytoskeleton and receptor signaling were uniquely enriched for low-dose (0.1 Gy) X-rays. In contrast, DNA/RNA metabolism and cell cycle regulation were enriched for high-dose (1 Gy) X-rays and 56 Fe ions, with more significant effects from 56 Fe ions. Specifically, DNA replication, DNA strand elongation, and DNA binding/transferase activity were perturbed more severely by 1 Gy 56 Fe ions than by 1 Gy X-rays, consistent with the significant G2/M arrest for the former while not for the latter. Conclusions: 56 Fe ions exert more significant effects on hMSC than X-rays. Since hMSC are the progenitors of osteoblasts in vivo, this study provides new mechanistic understandings of the relative health risks associated with low- and high-dose X-rays and high-LET space radiation

  4. Cell cycle variation in x-ray survival for cells from spheroids measured by volume cell sorting

    International Nuclear Information System (INIS)

    Freyer, J.P.; Wilder, M.E.; Raju, M.R.

    1984-01-01

    Considerable work has been done studying the variation in cell survival as a function of cell cycle position for monolayers or single cells exposed to radiation. Little is known about the effects of multicellular growth on the relative radiation sensitivity of cells in different cell cycle stages. The authors have developed a new technique for measuring the response of cells, using volume cell sorting, which is rapid, non-toxic, and does not require cell synchronization. By combining this technique with selective spheroid dissociation,they have measured the age response of cells located at various depths in EMT6 and Colon 26 spheroids. Although cells in the inner region had mostly G1-phase DNA contents, 15-20% had S- and G2-phase DNA contents. Analysis of these cells using BrdU labeling and flow cytometric analysis with a monoclonal antibody to BrdU indicated that the inner region cells were not synthesizing DNA. Thus, the authors were able to measure the radiation response of cells arrested in G1, S and G2 cell cycle phases. Comparison of inner and outer spheroid regions, and monolayer cultures, indicates that it is improper to extrapolate age response data in standard culture conditions to the situation in spheroids

  5. X-ray Raman spectroscopy of lithium-ion battery electrolyte solutions in a flow cell.

    Science.gov (United States)

    Ketenoglu, Didem; Spiekermann, Georg; Harder, Manuel; Oz, Erdinc; Koz, Cevriye; Yagci, Mehmet C; Yilmaz, Eda; Yin, Zhong; Sahle, Christoph J; Detlefs, Blanka; Yavaş, Hasan

    2018-03-01

    The effects of varying LiPF 6 salt concentration and the presence of lithium bis(oxalate)borate additive on the electronic structure of commonly used lithium-ion battery electrolyte solvents (ethylene carbonate-dimethyl carbonate and propylene carbonate) have been investigated. X-ray Raman scattering spectroscopy (a non-resonant inelastic X-ray scattering method) was utilized together with a closed-circle flow cell. Carbon and oxygen K-edges provide characteristic information on the electronic structure of the electrolyte solutions, which are sensitive to local chemistry. Higher Li + ion concentration in the solvent manifests itself as a blue-shift of both the π* feature in the carbon edge and the carbonyl π* feature in the oxygen edge. While these oxygen K-edge results agree with previous soft X-ray absorption studies on LiBF 4 salt concentration in propylene carbonate, carbon K-edge spectra reveal a shift in energy, which can be explained with differing ionic conductivities of the electrolyte solutions.

  6. Hydrothermal Diamond Anvil Cell (HDAC): From Visual Observation to X-ray Absorption Spectroscopy

    Science.gov (United States)

    Bassett, W. A.; Mibe, K.

    2006-05-01

    A fluid sample contained in a Re gasket between two diamond anvils can be subjected to pressures up to 2.5 GPa and temperatures up to 1200°C in a resistively heated hydrothermal diamond anvil cell (HDAC). Thermocouples are used to measure temperature. The constant-volume sample chamber permits isochoric measurements that can be used to determine pressure from the equation of state of H2O and to map phases and properties in P-T space. A movie of reactions between K-feldspar and water up to 2.5 GPa and 880°C illustrates the use of visual observations for mapping coexisting solution, melt, and solid phases. X-ray absorption spectroscopy of ZnBr2 in solution up to 500°C and 500 MPa shows hydrogen bond breaking in the hydration shells of the ZnBr42- and Br- ions with increasing temperature. In other studies the stability field of ikaite (CaCO3·6H2O) has been mapped by visual observation and Raman spectroscopy; the phases of montmorillonite have been mapped by X-ray diffraction; and the leaching of Pb from zircon has been measured by X-ray microprobe.

  7. Bystander effects and compartmental stress response to X-ray irradiation in L929 cells.

    Science.gov (United States)

    Temelie, Mihaela; Stroe, Daniela; Petcu, Ileana; Mustaciosu, Cosmin; Moisoi, Nicoleta; Savu, Diana

    2016-08-01

    Bystander effects are indirect consequences of radiation and many other stress factors. They occur in cells that are not directly exposed to these factors, but receive signals from affected cells either by gap junctions or by molecules released in the medium. Characterizing these effects and deciphering the underlying mechanisms involved in radiation-induced bystander effects are relevant for cancer radiotherapy and radioprotection. At doses of X-ray radiation 0.5 and 1 Gy, we detected bystander effects as increased numbers of micronuclei shortly after the treatment, through medium transfer and by co-cultures. Interestingly, bystander cells did not exhibit long-term adverse changes in viability. Evaluation of several compartmental stress markers (CHOP, BiP, mtHsp60, cytHsp70) by qRT-PCR did not reveal expression changes at transcriptional level. We investigated the involvement of ROS and NO in this process by addition of specific scavengers of these molecules, DMSO or c-PTIO in the transferred medium. This approach proved that ROS but not NO is involved in the induction of lesions in the acceptor cells. These results indicate that L929 cells are susceptible to stress effects of radiation-induced bystander signaling.

  8. Replicon sizes in mammalian cells as estimated by an x-ray plus bromodeoxyuridine photolysis method

    International Nuclear Information System (INIS)

    Kapp, L.N.; Painter, R.B.

    1978-01-01

    A new method is described for estimating replicon sizes in mammalian cells. Cultures were pulse labeled with [ 3 H]thymidine ([ 3 H]TdR) and bromodeoxyuridine (BrDUrd) for up to 1 h. The lengths of the resulting labeled regions of DNA, L/sub obs/, were estimated by a technique wherein the change in molecular weight of nascent DNA strands, induced by 313 nm light, is measured by velocity sedimentation in alkaline sucrose gradients. If cells are exposed to 1,000 rads of x rays immediately before pulse labeling, initiation of replicon operation is blocked, although chain elongation proceeds almost normally. Under these conditions L/sub obs/ continues to increase only until operating replicons have completed their replication. This value for L/sub obs/ then remains constant as long as the block to initiation remains and represents an estimate for the average size of replicons operating in the cells before x irradiation. For human diploid fibroblasts and human HeLa cells this estimated average size is approximately 17 μM, whereas for Chinese hamster ovary cells, the average replicon size is about 42 μM

  9. Long-term hematopoietic stem cell damage after external irradiation with X rays

    International Nuclear Information System (INIS)

    Grande, M.T.; Varas, F.; Bueren, J.A.

    1997-01-01

    We have investigated the functionality of the lympho-hematopoietic stem cells long-term (9 months) after the irradiation (X rays) of mice at different stages of development, by means of a competitive bone marrow repopulation assay. Our data revealed that a dose of 1 Gy was only capable of inducing significant long-term failures in the functionality of the primitive repopulating cells in mice irradiated at the young-adult stage (12 week-old), but not in mice irradiated at the late stages of foetus development (17 day-old fetuses) nor at the early development of the embryo (4 day-old embryos). The differential generation of long-term stem cell defects as a function of the age was confirmed in mice irradiated with 3 Gy. While no significant effects in the long-term repopulating cells were observed in 4 day-old embryos, significant repopulation deficiencies were observed in this population when mice were irradiated at the 17 day of foetus development, and more markedly at the adult stage of growth. These data offer new evidence about the influence of the developmental stage of the animal on the generation of residual hematopoietic dysfunctions by external irradiation, with particular relevance to the very primitive lympho-hematopoietic stem cells. (author)

  10. Quantitative computed tomography of lung parenchyma in patients with emphysema: analysis of higher-density lung regions

    Science.gov (United States)

    Lederman, Dror; Leader, Joseph K.; Zheng, Bin; Sciurba, Frank C.; Tan, Jun; Gur, David

    2011-03-01

    Quantitative computed tomography (CT) has been widely used to detect and evaluate the presence (or absence) of emphysema applying the density masks at specific thresholds, e.g., -910 or -950 Hounsfield Unit (HU). However, it has also been observed that subjects with similar density-mask based emphysema scores could have varying lung function, possibly indicating differences of disease severity. To assess this possible discrepancy, we investigated whether density distribution of "viable" lung parenchyma regions with pixel values > -910 HU correlates with lung function. A dataset of 38 subjects, who underwent both pulmonary function testing and CT examinations in a COPD SCCOR study, was assembled. After the lung regions depicted on CT images were automatically segmented by a computerized scheme, we systematically divided the lung parenchyma into different density groups (bins) and computed a number of statistical features (i.e., mean, standard deviation (STD), skewness of the pixel value distributions) in these density bins. We then analyzed the correlations between each feature and lung function. The correlation between diffusion lung capacity (DLCO) and STD of pixel values in the bin of -910HU lung parenchyma and lung function, which indicates that similar to the conventional density mask method, the pixel value distribution features in "viable" lung parenchyma areas may also provide clinically useful information to improve assessments of lung disease severity as measured by lung functional tests.

  11. Low-energy X-ray treatment of basal-cell carcinomas on and around eyelids

    International Nuclear Information System (INIS)

    Hendel, B.

    1982-01-01

    The results and experience gained with soft-radiation therapy of eyelid basal-cell carcinomas at the Dermatological University Clinic of Munich are presented in this thesis which supplies statistical data specific of patients and basilomas, discusses the irradiation technique used and compares it with those applied in other medical centres. Next it submits the curative results of eyelid basiloma irradiation comparing these with those obtained in other clinics. A separate chapter is dedicated to relapses showing i.a. possible recidivation causes followed by a presentation of each relapse case. The thesis concludes with a comparison of X-ray therapy and its results in the treatment of eyelid basal-cell carcinomas with other therapeutical methods and their results. (orig./MG) [de

  12. Cellular track model of biological damage to mammalian cell cultures from galactic cosmic rays

    Science.gov (United States)

    Cucinotta, Francis A.; Katz, Robert; Wilson, John W.; Townsend, Lawrence W.; Nealy, John E.; Shinn, Judy L.

    1991-01-01

    The assessment of biological damage from the galactic cosmic rays (GCR) is a current interest for exploratory class space missions where the highly ionizing, high-energy, high-charge ions (HZE) particles are the major concern. The relative biological effectiveness (RBE) values determined by ground-based experiments with HZE particles are well described by a parametric track theory of cell inactivation. Using the track model and a deterministic GCR transport code, the biological damage to mammalian cell cultures is considered for 1 year in free space at solar minimum for typical spacecraft shielding. Included are the effects of projectile and target fragmentation. The RBE values for the GCR spectrum which are fluence-dependent in the track model are found to be more severe than the quality factors identified by the International Commission on Radiological Protection publication 26 and seem to obey a simple scaling law with the duration period in free space.

  13. Cellular track model of biological damage to mammalian cell cultures from galactic cosmic rays

    International Nuclear Information System (INIS)

    Cucinotta, F.A.; Katz, R.; Wilson, J.W.; Townsend, L.W.; Nealy, J.E.; Shinn, J.L.

    1991-02-01

    The assessment of biological damage from the galactic cosmic rays (GCR) is a current interest for exploratory class space missions where the highly ionizing, high-energy, high-charge ions (HZE) particles are the major concern. The relative biological effectiveness (RBE) values determined by ground-based experiments with HZE particles are well described by a parametric track theory of cell inactivation. Using the track model and a deterministic GCR transport code, the biological damage to mammalian cell cultures is considered for 1 year in free space at solar minimum for typical spacecraft shielding. Included are the effects of projectile and target fragmentation. The RBE values for the GCR spectrum which are fluence-dependent in the track model are found to be more severe than the quality factors identified by the International Commission on Radiological Protection publication 26 and seem to obey a simple scaling law with the duration period in free space

  14. Histochemical applications of x-ray microanalysis: the simultaneous assessment of mitosis and cell death

    International Nuclear Information System (INIS)

    Bowen, I.D.; Lewis, G.H.

    1980-01-01

    The principles of x-ray microanalytical histochemistry are reviewed. The use of labelling and precipitation techniques are examined, and particular attention is paid to the localization of enzymatic activity. A new method is described for the simultaneous assessment of mitosis as represented by the incorporation of ( 3 H) thymidine, and cell death as represented by the localization of free acid phosphatase, in the same tissue section. The thymidine incorporation is demonstrated by the appearance of topographically and microanalytically detectable silver grains in an overlying emulsion and the cell lysis associated acid phosphatase activity is detected optically and microanalytically by means of a bromine-rich azo dye deposited as a result of coupling naphthol AS BI, enzymatically released from naphthyl AS BI phosphoric acid, with diazotized 2,5-dibromoaniline

  15. The response of hypoxic cells in SCCVII murine tumors to treatment with cisplatin and x rays

    International Nuclear Information System (INIS)

    Yan, R.D.; Durand, R.E.

    1991-01-01

    Possible mechanisms of enhancement of radiation effects by cisplatin, including radiosensitization of hypoxic cells, drug-induced tumor reoxygenation, and inhibition of repair of sublethal radiation damage, were examined in the murine SCCVII model. Combination radiation/drug treatments were most effective when drug exposure preceded irradiation of animals breathing a reduced oxygen atmosphere, indicating that the primary interaction between the modalities was a cisplatin-induced increase in the oxygenation status of the acutely hypoxic cells in those tumors. Delivering cisplatin prior to or immediately after the first of two 5 Gy fractions was more effective than combinations with a single x-ray exposure, suggesting that proper sequences of the combined modalities may augment natural reoxygenation processes

  16. Development of a spectro-electrochemical cell for soft X-ray photon-in photon-out spectroscopy

    Science.gov (United States)

    Ishihara, Tomoko; Tokushima, Takashi; Horikawa, Yuka; Kato, Masaru; Yagi, Ichizo

    2017-10-01

    We developed a spectro-electrochemical cell for X-ray absorption and X-ray emission spectroscopy, which are element-specific methods to study local electronic structures in the soft X-ray region. In the usual electrochemical measurement setup, the electrode is placed in solution, and the surface/interface region of the electrode is not normally accessible by soft X-rays that have low penetration depth in liquids. To realize soft X-ray observation of electrochemical reactions, a 15-nm-thick Pt layer was deposited on a 150-nm-thick film window with an adhesive 3-nm-thick Ti layer for use as both the working electrode and the separator window between vacuum and a sample liquid under atmospheric pressure. The designed three-electrode electrochemical cell consists of a Pt film on a SiC window, a platinized Pt wire, and a commercial Ag|AgCl electrode as the working, counter, and reference electrodes, respectively. The functionality of the cell was tested by cyclic voltammetry and X-ray absorption and emission spectroscopy. As a demonstration, the electroplating of Pb on the Pt/SiC membrane window was measured by X-ray absorption and real-time monitoring of fluorescence intensity at the O 1s excitation.

  17. Biological X-ray irradiator characterization for use with small animals and cells.

    Science.gov (United States)

    Bruno, A Colello; Mazaro, S J; Amaral, L L; Rego, E M; Oliveira, H F; Pavoni, J F

    2017-03-02

    This study presents the characterization of an X-ray irradiator through dosimetric tests, which confirms the actual dose rate that small animals and cells will be exposed to during radiobiological experiments. We evaluated the linearity, consistency, repeatability, and dose distribution in the positions in which the animals or cells are placed during irradiation. In addition, we evaluated the performance of the X-ray tube (voltage and tube operating current), the radiometric survey (leakage radiation) and safety devices. The irradiator default setting was established as 160 kV and 25 mA. Tests showed that the dose rate was linear overtime (R2=1) and remained stable for long (constant) and short (repeatability) intervals between readings. The mean dose rate inside the animal cages was 1.27±0.06 Gy/min with a uniform beam of 95.40% (above the minimum threshold guaranteed by the manufacturer). The mean dose rate inside the cell plates was 0.92±0.19 Gy/min. The dose rate dependence with tube voltage and current presented a quadratic and linear relationship, respectively. There was no observed mechanical failure during evaluation of the irradiator safety devices and the radiometric survey obtained a maximum ambient equivalent dose rate of 0.26 mSv/h, which exempts it from the radiological protection requirements of the International Atomic Energy Agency. The irradiator characterization enables us to perform radiobiological experiments, and assists or even replaces traditional therapy equipment (e.g., linear accelerators) for cells and small animal irradiation, especially in early research stages.

  18. Biological X-ray irradiator characterization for use with small animals and cells

    Directory of Open Access Journals (Sweden)

    A. Colello Bruno

    Full Text Available This study presents the characterization of an X-ray irradiator through dosimetric tests, which confirms the actual dose rate that small animals and cells will be exposed to during radiobiological experiments. We evaluated the linearity, consistency, repeatability, and dose distribution in the positions in which the animals or cells are placed during irradiation. In addition, we evaluated the performance of the X-ray tube (voltage and tube operating current, the radiometric survey (leakage radiation and safety devices. The irradiator default setting was established as 160 kV and 25 mA. Tests showed that the dose rate was linear overtime (R2=1 and remained stable for long (constant and short (repeatability intervals between readings. The mean dose rate inside the animal cages was 1.27±0.06 Gy/min with a uniform beam of 95.40% (above the minimum threshold guaranteed by the manufacturer. The mean dose rate inside the cell plates was 0.92±0.19 Gy/min. The dose rate dependence with tube voltage and current presented a quadratic and linear relationship, respectively. There was no observed mechanical failure during evaluation of the irradiator safety devices and the radiometric survey obtained a maximum ambient equivalent dose rate of 0.26 mSv/h, which exempts it from the radiological protection requirements of the International Atomic Energy Agency. The irradiator characterization enables us to perform radiobiological experiments, and assists or even replaces traditional therapy equipment (e.g., linear accelerators for cells and small animal irradiation, especially in early research stages.

  19. In vivo proton MR spectroscopy of normal liver parenchyma: technique and results

    International Nuclear Information System (INIS)

    Mueller, C.; Huebner, F.; Bisdas, S.; Herzog, C.; Hammerstingl, R.M.; Vogl, T.J.; Ackermann, H.; Vorbuchner, M.

    2006-01-01

    Purpose: To analyze the proton magnetic resonance spectroscopic data ( 1 H MRS) of normal liver parenchyma with regard to age, sex, body mass index and location in the liver. Materials and Methods: 45 healthy volunteers age 24 to 65 years were examined with an optimized single-voxel 1 H MRS using a 1.5-T scanner. A spin echo sequence with a TR of 1500 ms and a TE of 135 ms was used, allowing in-phase detection of the choline signal. Weak water suppression was achieved using a chemical shift selective suppression (CHESS) technique. Each examination included the measurement of three voxels with a voxel size of 18 x 18 x 18 mm 3 in different areas of the liver. The volunteers were divided into different age-based groups (young: ≤44 years; older: ≥44 years), BMI (normal weighted: 2 ; obese: >25 kg/m 2 ) and sex. Results: In the acquired spectra different lipid (e.g. [CH 2 ] n ), choline, glutamine, glutamate and glycogenglucose-complex reasonances were detected. The analysis of the spectra, however, only focused on the concentrations of choline and (CH 2 ) n and the relative concentrations of the choline-to-(CH 2 ) n -ratios. In the older volunteers the relative concentration of the choline-to-(CH 2 ) n -ratio was significantly decreased by 0.213±0.193 in comparison to the younger subjects (p=0,031). Further statistical analysis confirmed a significant decrease of the choline-to-(CH 2 ) n -ratio by 0.223±0.180 in obese volunteers compared to volunteers of a standard weight (p=0,016). The significant difference between the choline-to-(CH 2 ) n -ratio female versus male volunteers was calculated with an increase of 0.483±0.172 (p=0,000). The location of the voxel in the liver parenchyma did not yield a signficant difference in the choline-to-(CH 2 ) n -ratio. (orig.)

  20. Three-dimensional Invasion of Human Glioblastoma Cells Remains Unchanged by X-ray and Carbon Ion Irradiation In Vitro

    Energy Technology Data Exchange (ETDEWEB)

    Eke, Iris; Storch, Katja; Kaestner, Ina; Vehlow, Anne [OncoRay-National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden (Germany); Faethe, Christina; Mueller-Klieser, Wolfgang [Institute of Physiology and Pathophysiology, University Medical Center of the Johannes Gutenberg University Mainz, Mainz (Germany); Taucher-Scholz, Gisela [Department of Biophysics, GSI Helmholtz Center for Heavy Ion Research, Darmstadt (Germany); Temme, Achim; Schackert, Gabriele [Section of Experimental Neurosurgery/Tumor Immunology, Department of Neurosurgery, University Hospital Carl Gustav Carus, Dresden University of Technology, Dresden (Germany); Cordes, Nils, E-mail: Nils.Cordes@Oncoray.de [OncoRay-National Center for Radiation Research in Oncology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden (Germany); Department of Radiation Oncology, Medical Faculty Carl Gustav Carus, Dresden University of Technology, Dresden (Germany)

    2012-11-15

    Purpose: Cell invasion represents one of the major determinants that treatment has failed for patients suffering from glioblastoma. Contrary findings have been reported for cell migration upon exposure to ionizing radiation. Here, the migration and invasion capability of glioblastoma cells on and in collagen type I were evaluated upon irradiation with X-rays or carbon ions. Methods and Materials: Migration on and invasion in collagen type I were evaluated in four established human glioblastoma cell lines exposed to either X-rays or carbon ions. Furthermore, clonogenic radiation survival, proliferation (5-bromo-2-deoxyuridine positivity), DNA double-strand breaks ({gamma}H2AX/53BP1-positive foci), and expression of invasion-relevant proteins (eg, {beta}1 integrin, FAK, MMP2, and MMP9) were explored. Migration and invasion assays for primary glioblastoma cells also were carried out with X-ray irradiation. Results: Neither X-ray nor carbon ion irradiation affected glioblastoma cell migration and invasion, a finding similarly observed in primary glioblastoma cells. Intriguingly, irradiated cells migrated unhampered, despite DNA double-strand breaks and reduced proliferation. Clonogenic radiation survival was increased when cells had contact with extracellular matrix. Specific inhibition of the {beta}1 integrin or proliferation-associated signaling molecules revealed a critical function of JNK, PI3K, and p38 MAPK in glioblastoma cell invasion. Conclusions: These findings indicate that X-rays and carbon ion irradiation effectively reduce proliferation and clonogenic survival without modifying the migration and invasion ability of glioblastoma cells in a collagen type I environment. Addition of targeted agents against members of the MAPK and PI3K signaling axis to conventional chemoradiation therapy seems potentially useful to optimize glioblastoma therapy.

  1. Cytological characterization of Chinese hamster ovary X-ray-sensitive mutant cells xrs 5 and xrs 6. 1

    International Nuclear Information System (INIS)

    Darroudi, F.

    1987-01-01

    The authors have determined the rate of progression of the cell cycle of irradiated cells in the presence of caffeine as well as the potentiating effect of caffeine on the frequency of chromosomal aberrations after X-irradiation. The characteristics for survival, frequency of chromosomal alterations and cell cycle progression in the presence or absence of 3-aminobenzamide (3AB) and caffeine of X-irradiated xrs 5, xrs 6 and parental wild-type CHO-K1 cells are discussed and compared to other X-ray-sensitive cells such as cells from ataxia telangiectasia patients. (Auth.)

  2. Radiobiologic significance of apoptosis and micronucleation in quiescent cells within solid tumors following γ-ray irradiation

    International Nuclear Information System (INIS)

    Masunaga, Shin-ichiro; Ono, Koji; Suzuki, Minoru; Kinashi, Yuko; Takagaki, Masao

    2001-01-01

    Purpose: To determine the frequency of apoptosis in quiescent (Q) cells within solid tumors following γ-ray irradiation, using four different tumor cell lines. In addition, to assess the significance of detecting apoptosis in these cell lines. Methods and Materials: C3H/He mice bearing SCC VII or FM3A tumors, Balb/c mice bearing EMT6/KU tumors, and C57BL mice bearing EL4 tumors received 5-bromo-2'-deoxyuridine (BrdU) continuously for 5 days via implanted mini-osmotic pumps to label all proliferating (P) cells. The mice then received γ-ray irradiation at a dose of 4-25 Gy while alive or after tumor clamping. Immediately after irradiation, the tumors were excised, minced, and trypsinized. The tumor cell suspensions thus obtained were incubated with cytochalasin-B (a cytokinesis blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (=Q cells) was determined using immunofluorescence staining for BrdU. Meanwhile, 6 hours after irradiation, tumor cell suspensions obtained in the same manner were fixed. The apoptosis frequency in Q cells was also determined with immunofluorescence staining for BrdU. The MN and apoptosis frequency in total (P+Q) tumor cells were determined from the tumors that were not pretreated with BrdU. Results: In total cells, SCC VII, FM3A, and EMT6/KU cells showed reasonable relationships between MN frequency and surviving fraction (SF). However, fewer micronuclei were induced in EL4 cells than the other cell lines. In contrast, a comparatively close relationship between apoptosis frequency and SF was found in total cells of EL4 cell line. Less apoptosis was observed in the other cell lines. Quiescent tumor cells exhibited significantly lower values of MN and apoptosis frequency probably due to their large hypoxic fraction, similar to total tumor cells on clamped irradiation. Conclusion: γ-ray irradiation induced MN formation in SCC VII, FM3A, and EMT6/KU tumor cells, and the apoptosis was marked in EL4 cells compared with

  3. Brain parenchyma PO2, PCO2, and pH during and after hypoxic, ischemic brain insult in dogs.

    Science.gov (United States)

    McKinley, B A; Morris, W P; Parmley, C L; Butler, B D

    1996-11-01

    1) The investigation of fiberoptic PO2, PCO2, and pH sensor technology as a monitor of brain parenchyma during and after brain injury, and 2) the comparison of brain parenchyma PO2, PCO2, and pH with intracranial pressure during and after hypoxic, ischemic brain insult. Prospective, controlled, animal study in an acute experimental preparation. Physiology laboratory in a university medical school. Fourteen mongrel dogs (20 to 35 kg), anesthetized, room-air ventilated. Anesthesia was induced with thiopental and maintained after intubation using 1% to 1.5% halothane in room air (FiO2 0.21). Mechanical ventilation was established to maintain end-tidal PCO2 approximately 35 torr (-4.7 kPa). Intravenous, femoral artery, and pulmonary artery catheters were placed. The common carotid arteries were surgically exposed, and ultrasonic blood flow probes were applied. A calibrated intracranial pressure probe was placed through a right-side transcranial bolt, and a calibrated intracranial chemistry probe with optical sensors for PO2, PCO2, and pH was placed through a left-side bolt into brain parenchyma. Brain insult was induced in the experimental group (n = 6) by hypoxia (FiO2 0.1), ischemia (bilateral carotid artery occlusion), and hypotension (mean arterial pressure [MAP] approximately 40 mm Hg produced with isoflurane approximately 4%). After 45 mins, carotid artery occlusion was released, FiO2 was reset to 0.21, and anesthetic was returned to halothane (approximately 1.25%). The control group (n = 5) had the same surgical preparation and sequence of anesthetic agent exposure but no brain insult. Monitored variables included brain parenchyma PO2, PCO2, and pH, which were monitored at 1-min intervals, and intracranial pressure, MAP, arterial hemoglobin oxygen saturation (by pulse oximetry), end-tidal PCO2, and carotid artery blood flow rate, for which data were collected at 15-min intervals for 7 hrs. Arterial and mixed venous blood gas analyses were done at approximately 1

  4. A cell for extended x-ray absorption fine structure studies of oxygen sensitive products of redox reactions

    International Nuclear Information System (INIS)

    Furenlid, L.R.; Renner, M.W.; Fajer, J.

    1990-01-01

    We describe a cell suitable for extended x-ray absorption fine structure (EXAFS) studies of oxygen and/or water sensitive products of redox reactions. The cell utilizes aluminized Mylar windows that are transparent to x rays, provide low gas permeability, and allow vacuum to be maintained in the cell. The windows are attached to the glassware with an epoxy that resists attack by common organic solvents. Additional side arms allow multiple spectroscopic probes of the same sample under anaerobic and anhydrous conditions

  5. Exposure to Low-Dose X-Ray Radiation Alters Bone Progenitor Cells and Bone Microarchitecture.

    Science.gov (United States)

    Lima, Florence; Swift, Joshua M; Greene, Elisabeth S; Allen, Matthew R; Cunningham, David A; Braby, Leslie A; Bloomfield, Susan A

    2017-10-01

    Exposure to high-dose ionizing radiation during medical treatment exerts well-documented deleterious effects on bone health, reducing bone density and contributing to bone growth retardation in young patients and spontaneous fracture in postmenopausal women. However, the majority of human radiation exposures occur in a much lower dose range than that used in the radiation oncology clinic. Furthermore, very few studies have examined the effects of low-dose ionizing radiation on bone integrity and results have been inconsistent. In this study, mice were irradiated with a total-body dose of 0.17, 0.5 or 1 Gy to quantify the early (day 3 postirradiation) and delayed (day 21 postirradiation) effects of radiation on bone microarchitecture and bone marrow stromal cells (BMSCs). Female BALBc mice (4 months old) were divided into four groups: irradiated (0.17, 0.5 and 1 Gy) and sham-irradiated controls (0 Gy). Micro-computed tomography analysis of distal femur trabecular bone from animals at day 21 after exposure to 1 Gy of X-ray radiation revealed a 21% smaller bone volume (BV/TV), 22% decrease in trabecular numbers (Tb.N) and 9% greater trabecular separation (Tb.Sp) compared to sham-irradiated controls (P X-rays, whereas osteoclastogenesis was enhanced. A better understanding of the effects of radiation on osteoprogenitor cell populations could lead to more effective therapeutic interventions that protect bone integrity for individuals exposed to low-dose ionizing radiation.

  6. Chromosome alterations in the X-ray-induced transformants of cultured mouse cell line

    International Nuclear Information System (INIS)

    Kodama, Seiji; Komatsu, Kenshi; Okumura, Yutaka; Sasaki, M.S.

    1989-01-01

    Mouse m5S cells were subjected to soft X-ray irradiation. Twenty-four transformants were separated as indicators of focus formation. Two clones, cl.4103 and cl.6310, were chosen for the analysis of chromosome alterations in transformants. A parent strain, m5S/1M, served as the control. Anchorage independence (AG) was not detected in the control strain, irrespective of culture conditions and population doubling number (PDN). In the case of transformants, the frequency of AG was increased with increasing PDN for cl.4103, and was constant for cl.6310, irrespective of PDN. Karyotype of m5S/1M was 42, X, -Y, +der (6) t(6;13), t(8;8), +8, +15. In addition, -13, der(10) and -der(6)t(6;13), der(5), +mar occurred as karyotype alterations for cl.4103 and cl. 6310, respectively. The present experiment indicated that chromosome alterations secondary to primary alterations occur in a high frequency in the transforming process of X-ray irradiated cells, and that the secondary chromosome alterations result in selective proliferation of transformed clones. (Namekawa, K)

  7. Alpha Particles and X Rays Interact in Inducing DNA Damage in U2OS Cells.

    Science.gov (United States)

    Sollazzo, Alice; Brzozowska, Beata; Cheng, Lei; Lundholm, Lovisa; Haghdoost, Siamak; Scherthan, Harry; Wojcik, Andrzej

    2017-10-01

    Survivors of the atomic bombings of Hiroshima and Nagasaki are monitored for health effects within the Life Span Study (LSS). The LSS results represent the most important source of data about cancer effects from ionizing radiation exposure, which forms the foundation for the radiation protection system. One uncertainty connected to deriving universal risk factors from these results is related to the problem of mixed radiation qualities. The A-bomb explosions generated a mixed beam of the sparsely ionizing gamma radiation and densely ionizing neutrons. However, until now the possible interaction of the two radiation types of inducing biological effects has not been taken into consideration. The existence of such interaction would suggest that the application of risk factors derived from the LSS to predict cancer effects after pure gamma-ray irradiation (such as in the Fukushima prefecture) leads to an overestimation of risk. To analyze the possible interaction of radiation types, a mixed-beam exposure facility was constructed where cells can be exposed to sparsely ionizing X rays and densely ionizing alpha particles. U2OS cells were used, which are stably transfected with a plasmid coding for the DNA repair gene 53BP1 coupled to a gene coding for the green fluorescent protein (GFP). The induction and repair of DNA damage, which are known to be related to cancer induction, were analyzed. The results suggest that alpha particles and X rays interact, leading to cellular and possibly cancer effects, which cannot be accurately predicted based on assuming simple additivity of the individual mixed-beam components.

  8. Observation of injury effects and apoptosis induced by microwave and gamma ray on lymphocyte in Raji cell

    International Nuclear Information System (INIS)

    Xia Hongjie; Wang Dewen; Zuo Hongyan; Xu Xinping; Jia Kai; Qiu Bingtao

    2011-01-01

    To investigate the rule of apoptosis, necrosis and the effects of Raji cell induced by microwave and gamma ray, the Raji cell was exposed to microwave radiation and gamma radiation. Morphological changes were observed by inverted phase contrast microscope before and after radiation. Annexin-V and PI double labelling were used to detect changes of apoptosis and necrosis rate. The results show that the cell shape was changed and the rate of apoptosis and necrosis were increased after exposure to microwave and γ ray. The injury effect of γ+S-HPM compound radiation was more serious than any single radiation on lymphocyte. The major characteristics of injury showed as gamma ray effect. The trends of apoptosis and necrosis keep consistency with the change of the cell morphology after radiation between each observation group. (authors)

  9. Comparative analysis of contrast between hepatic vein and hepatic parenchyma with controlled velocity of ultrasound in normal and fatty liver

    International Nuclear Information System (INIS)

    Yun, Eun Joo; Choi, Byung Jin; Han, Joon Koo; Cha, Joo Hee; Kim, Seung Hyup; Lee, Dong Hyuk

    2000-01-01

    To evaluate the contrast between hepatic vein and hepatic parenchyma with controlled velocities of ultrasound in normal and fatty liver. 31 patient with normal liver and 39 patients with moderate degree of fatty liver were studies with sonography with controlled velocities of ultrasound (1,580 m/sec, 1,540 m/sec, 1,500 m/sec, 1,460 m/sec). Sonographic images were captured with picture grabbing (Sono-PACS) and were recalled with visual C++(Microsoft Redmond. WA, USA). The contrast between hepatic vein and parenchyma was measured and analyzed on each sonographic image. The number of patients with the highest contrast between hepatic vein and hepatic parenchyma among the 31 patients with normal liver were 5 (16.1%) with 1,580 m/sec, 12 (38.8%) with 1,540 m/sec, 9 (29.0%) with 1,500 m/sec, and 5 (16.1%) with 1,460 m/sec. The number of patients with highest contrast between hepatic vein and hepatic parenchyma among the 39 patients with fatty liver were 3 (7.7%) with 1,580 m/sec, 7 (17.9%) with 1,540 m/sec, 12 (30.8%) with 1,500 m/sec and 17 (43.6%) with 1,460 m/sec. The velocity of ultrasound for the highest contrast between hepatic vein and hepatic parenchyma in normal liver was 1,540 m/sec, and 1,460 m/sec in fatty liver.

  10. Sulfur X-Ray Absorption Spectroscopy of Living Mammalian Cells: An Enabling Tool for Sulfur Metabolomics. in Situ Observation of Uptake of Taurine Into MDCK Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gnida, M.; Sneeden, E.Yu; Whitin, J.C.; Prince, R.C.; Pickering, I.J.; Korbas, M.; George, G.N.

    2009-06-01

    Sulfur is essential for life, with important roles in biological structure and function. However, because of a lack of suitable biophysical techniques, in situ information about sulfur biochemistry is generally difficult to obtain. Here, we present an in situ sulfur X-ray absorption spectroscopy (S-XAS) study of living cell cultures of the mammalian renal epithelial MDCK cell line. A great deal of information is retrieved from a characteristic sulfonate feature in the X-ray absorption spectrum of the cell cultures, which can be related to the amino acid taurine. We followed the time and dose dependence of uptake of taurine into MDCK cell monolayers. The corresponding uptake curves showed a typical saturation behavior with considerable levels of taurine accumulation inside the cells (as much as 40% of total cellular sulfur). We also investigated the polarity of uptake of taurine into MDCK cells, and our results confirmed that uptake in situ is predominantly a function of the basolateral cell surface.

  11. Morphological peculiarity of the renal parenchyma on S10 thin plastinated pig kidneys

    Directory of Open Access Journals (Sweden)

    Pendovski Lazo

    2008-11-01

    Full Text Available The aim of this study is to investigate the morphological structures on the renal parenchyma on the pig kidneys, prepared in thin slices by S10 sheet plastination method. A total number of 60 kidneys taken form two adult breeds are plastinated in 2mm sagital thin sections. The morphological structure on thin kidney slices is analyzed and their anatomic-topographical relationship is investigated. The prepared thin kidney slices are permanent, flexible, dry, and odorless with smooth surfaces anatomical models with clear distinction between renal medulla and renal cortex. In cross-bread landras/yorkshire, the number of renal pyramids is ranged between 8-14 (average 10.63 while in breed dalland the number is ranged between 8- 13(average 9.94(p>0.05. Three morphological forms are found in pig kidneys based of the variation of adhesion of renal pyramids and derange of their renal papilla into renal pelvis. According the results can be concluded that the S10 sheet plastination method could be used for preparing of thin anatomical models that are suitable for education and research purposes enabling three-dimensional plan view of anatomical structures inside of kidneys.

  12. Areas of normal pulmonary parenchyma on HRCT exhibit increased FDG PET signal in IPF patients

    International Nuclear Information System (INIS)

    Win, Thida; Thomas, Benjamin A.; Lambrou, Tryphon; Hutton, Brian F.; Endozo, Raymondo; Shortman, Robert I.; Afaq, Asim; Ell, Peter J.; Groves, Ashley M.; Screaton, Nicholas J.; Porter, Joanna C.; Maher, Toby M.; Lukey, Pauline

    2014-01-01

    Patients with idiopathic pulmonary fibrosis (IPF) show increased PET signal at sites of morphological abnormality on high-resolution computed tomography (HRCT). The purpose of this investigation was to investigate the PET signal at sites of normal-appearing lung on HRCT in IPF. Consecutive IPF patients (22 men, 3 women) were prospectively recruited. The patients underwent 18 F-FDG PET/HRCT. The pulmonary imaging findings in the IPF patients were compared to the findings in a control population. Pulmonary uptake of 18 F-FDG (mean SUV) was quantified at sites of morphologically normal parenchyma on HRCT. SUVs were also corrected for tissue fraction (TF). The mean SUV in IPF patients was compared with that in 25 controls (patients with lymphoma in remission or suspected paraneoplastic syndrome with normal PET/CT appearances). The pulmonary SUV (mean ± SD) uncorrected for TF in the controls was 0.48 ± 0.14 and 0.78 ± 0.24 taken from normal lung regions in IPF patients (p 18 F-FDG on PET in areas of lung with a normal morphological appearance on HRCT. This may have implications for determining disease mechanisms and treatment monitoring. (orig.)

  13. Areas of normal pulmonary parenchyma on HRCT exhibit increased FDG PET signal in IPF patients

    Energy Technology Data Exchange (ETDEWEB)

    Win, Thida [Lister Hospital, Respiratory Medicine, Stevenage (United Kingdom); Thomas, Benjamin A.; Lambrou, Tryphon; Hutton, Brian F.; Endozo, Raymondo; Shortman, Robert I.; Afaq, Asim; Ell, Peter J.; Groves, Ashley M. [University College London, Institute of Nuclear Medicine, University College Hospital, London (United Kingdom); Screaton, Nicholas J. [Papworth Hospital, Radiology Department, Papworth Everard (United Kingdom); Porter, Joanna C. [University College London, Centre for Respiratory Diseases, University College Hospital, London (United Kingdom); Maher, Toby M. [Royal Brompton Hospital, Interstitial Lung Disease Unit, London (United Kingdom); Lukey, Pauline [GSK, Fibrosis DPU, Research and Development, Stevenage (United Kingdom)

    2014-02-15

    Patients with idiopathic pulmonary fibrosis (IPF) show increased PET signal at sites of morphological abnormality on high-resolution computed tomography (HRCT). The purpose of this investigation was to investigate the PET signal at sites of normal-appearing lung on HRCT in IPF. Consecutive IPF patients (22 men, 3 women) were prospectively recruited. The patients underwent {sup 18}F-FDG PET/HRCT. The pulmonary imaging findings in the IPF patients were compared to the findings in a control population. Pulmonary uptake of {sup 18}F-FDG (mean SUV) was quantified at sites of morphologically normal parenchyma on HRCT. SUVs were also corrected for tissue fraction (TF). The mean SUV in IPF patients was compared with that in 25 controls (patients with lymphoma in remission or suspected paraneoplastic syndrome with normal PET/CT appearances). The pulmonary SUV (mean ± SD) uncorrected for TF in the controls was 0.48 ± 0.14 and 0.78 ± 0.24 taken from normal lung regions in IPF patients (p < 0.001). The TF-corrected mean SUV in the controls was 2.24 ± 0.29 and 3.24 ± 0.84 in IPF patients (p < 0.001). IPF patients have increased pulmonary uptake of {sup 18}F-FDG on PET in areas of lung with a normal morphological appearance on HRCT. This may have implications for determining disease mechanisms and treatment monitoring. (orig.)

  14. Correlation of neurocognitive function and brain parenchyma volumes in children surviving cancer

    Science.gov (United States)

    Reddick, Wilburn E.; White, Holly A.; Glass, John O.; Mulhern, Raymond K.

    2002-04-01

    This research builds on our hypothesis that white matter damage and associated neurocognitive symptoms, in children treated for cancer with cranial spinal irradiation, spans a continuum of severity that can be reliably probed using non-invasive MR technology. Quantitative volumetric assessments of MR imaging and psychological assessments were obtained in 40 long-term survivors of malignant brain tumors treated with cranial irradiation. Neurocognitive assessments included a test of intellect (Wechsler Intelligence Test for Children, Wechsler Adult Intelligence Scale), attention (Conner's Continuous Performance Test), and memory (California Verbal Learning Test). One-sample t-tests were conducted to evaluate test performance of survivors against age-adjusted scores from the test norms; these analyses revealed significant impairments in all apriori selected measures of intelligence, attention, and memory. Partial correlation analyses were performed to assess the relationships between brain tissues volumes (normal appearing white matter (NAWM), gray matter, and CSF) and neurocognitive function. Global intelligence (r = 0.32, p = 0.05) and global attentional (r = 0.49, p attentional deficits, whereas overall parenchyma loss, as reflected by increased CSF and decreased white matter, is associated with memory-related deficits.

  15. Agrin in Alzheimer's Disease: Altered Solubility and Abnormal Distribution within Microvasculature and Brain Parenchyma

    Science.gov (United States)

    Donahue, John E.; Berzin, Tyler M.; Rafii, Michael S.; Glass, David J.; Yancopoulos, George D.; Fallon, Justin R.; Stopa, Edward G.

    1999-05-01

    Agrin is a heparan sulfate proteoglycan that is widely expressed in neurons and microvascular basal lamina in the rodent and avian central nervous system. Agrin induces the differentiation of nerve-muscle synapses, but its function in either normal or diseased brains is not known. Alzheimer's disease (AD) is characterized by loss of synapses, changes in microvascular architecture, and formation of neurofibrillary tangles and senile plaques. Here we have asked whether AD causes changes in the distribution and biochemical properties of agrin. Immunostaining of normal, aged human central nervous system revealed that agrin is expressed in neurons in multiple brain areas. Robust agrin immunoreactivity was observed uniformly in the microvascular basal lamina. In AD brains, agrin is highly concentrated in both diffuse and neuritic plaques as well as neurofibrillary tangles; neuronal expression of agrin also was observed. Furthermore, patients with AD had microvascular alterations characterized by thinning and fragmentation of the basal lamina. Detergent extraction and Western blotting showed that virtually all the agrin in normal brain is soluble in 1% SDS. In contrast, a large fraction of the agrin in AD brains is insoluble under these conditions, suggesting that it is tightly associated with β -amyloid. Together, these data indicate that the agrin abnormalities observed in AD are closely linked to β -amyloid deposition. These observations suggest that altered agrin expression in the microvasculature and the brain parenchyma contribute to the pathogenesis of AD.

  16. Contrast between hypervascularized liver lesions and hepatic parenchyma. Early dynamic PET versus contrast-enhanced CT

    International Nuclear Information System (INIS)

    Freesmeyer, M.; Winkens, T.; Schierz, J.-H.

    2014-01-01

    To detect hypervascularized liver lesions, early dynamic (ED) 18 F-FDG PET may be an alternative when contrast-enhanced (CE) imaging is infeasible. This retrospective pilot analysis compared contrast between such lesions and liver parenchyma, an important objective image quality variable, in ED PET versus CE CT. Twenty-eight hypervascularized liver lesions detected by CE CT [21 (75%) hepatocellular carcinomas; mean (range) diameter 4.9 ± 3.5 (1-14) cm] in 20 patients were scanned with ED PET. Using regions of interest, maximum and mean lesional and parenchymal signals at baseline, arterial and venous phases were calculated for ED PET and CE CT. Lesional/parenchymal signal ratio was significantly higher (P < 0.005) with ED PET versus CE CT at the arterial phase and similar between the methods at the venous phase. In liver imaging, ED PET generates greater lesional-parenchymal contrast during the arterial phase than does CE CT; these observations should be formally, prospectively evaluated. (author)

  17. Inhibition of X-ray induced DNA strand break repair in polyamine-depleted HeLa cells

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, R.D.

    1989-05-01

    Treatment of HeLa cells with the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) or methylglyoxal bis(guanylhydrazone) (MGBG), results in, depending on the conditions, partial or complete depletion of the cellular polyamines: putrescine, spermidine and spermine. In this compromised state cells exhibited a distinct deficiency in repair of X-ray-induced DNA strand breaks. The half-time for return of normal DNA sedimentation following 1.6 Gy was 9.5 min for untreated control cells and 22, 32 and 50 min for cells treated with MGBG, DFMO+MGBG and DFMO, respectively. Normal repair kinetics were restored to these cells upon a short incubation in media containing all three polyamines. The rapid early phase of repair following higher X-ray doses (16 Gy) was also delayed in polyamine-depleted cells but later repair occurring 1-4 h post-irradiation, representing chromatin reconstitution, was apparently normal. (author).

  18. Inhibition of X-ray induced DNA strand break repair in polyamine-depleted HeLa cells

    International Nuclear Information System (INIS)

    Snyder, R.D.

    1989-01-01

    Treatment of HeLa cells with the polyamine biosynthesis inhibitors, alpha-difluoromethylornithine (DFMO) or methylglyoxal bis(guanylhydrazone) (MGBG), results in, depending on the conditions, partial or complete depletion of the cellular polyamines: putrescine, spermidine and spermine. In this compromised state cells exhibited a distinct deficiency in repair of X-ray-induced DNA strand breaks. The half-time for return of normal DNA sedimentation following 1.6 Gy was 9.5 min for untreated control cells and 22, 32 and 50 min for cells treated with MGBG, DFMO+MGBG and DFMO, respectively. Normal repair kinetics were restored to these cells upon a short incubation in media containing all three polyamines. The rapid early phase of repair following higher X-ray doses (16 Gy) was also delayed in polyamine-depleted cells but later repair occurring 1-4 h post-irradiation, representing chromatin reconstitution, was apparently normal. (author)

  19. The DNA damage of high doses of X-ray on human peripheral blood nucleated cell's and sperm

    International Nuclear Information System (INIS)

    Wang Hui; Zoulian; Jiang Qisheng; Li Fengsheng; He Rui; Song Xiujun

    2011-01-01

    Objective: To detect the DNA damage of high doses of X-ray on human peripheral blood nucleated cell's and sperm by single cell gel electrophoresis (SCGE). Evaluation the level of DNA damage of human peripheral blood nucleated cell's and sperm after high doses of X-ray. Methods: Using human peripheral blood with normal blood routine and normal sperm,give the dose of 0 Gy, 2 Gy, 4 Gy, 6 Gy, 8 Gy, 10 Gy X-ray radiation with energy of 6MU. Detect the percentage of comet-like tail, tail length and content of DNA in tail of whole blood cell's DNA and sperm's DNA by SCGE technique in 1 hour. Results: The peripheral blood nucleated cell's and sperm's comet rate were 1.00±0.10%, 2.1±1.5%, respectively, have an evidently variance in 0 Gy group (υ=18, t=2.31>1.734, P 1.734, P 1.734, P<0.05). The peripheral blood nucleated cell's and sperm's comet rate were all 100%, 100%, have no-statistical significance in 8 Gy, 10 Gy group. Conclusion: The evidence is powerful enough. That the sperm's SCGE is more sensitive than peripheral blood nucleated cell's SCGE in reflect the X-ray damage in a certain extent (2-6 Gy). (authors)

  20. Effect of combined treatment of x-rays and ACNU on rat glioma cells in monolayer and multicellular spheroids

    International Nuclear Information System (INIS)

    Sugiyama, Satoru; Mori, Teruaki; Suzuki, Jiro; Sasaki, Takehito

    1985-01-01

    Spheroids of rat glioma clone-6 cells having a central necrosis were used to determine the effect of combined treatment of x-rays and 1-(4-amino-2-methyl-5-pyrimidinyl)methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU), where the optimum time intervals and doses in the combination were analyzed. The treatment with ACNU 2 to 6 hours prior to x-ray irradiation was most effective for cells in both monolayers and in spheroids. The dose survival curves with x-ray irradiation indicated that the hypoxic cell fraction in spheroids disappeared with a prior treatment by ACNU. The enhancement ratio in spheroids was thus larger for larger x-ray doses, and was always larger than that in monolayer cells. The survival curves versus concentration of ACNU indicated that the enhancement ratio in spheroids was more than 1.2 in all concentrations with the combined x-ray irradiation, and exceeded that in monolayer cells with a surviving fraction of less than 0.4. (author)

  1. Adaptive response to ionizing radiation induced by low doses of gamma rays in human cell lines

    International Nuclear Information System (INIS)

    Seong, Jinsil; Chang, Ok Suh; Gwi, Eon Kim

    1995-01-01

    Purpose: The aim of this study was to investigate whether the adaptive response could be induced in human lymphoblastoid cell lines and human tumor cell lines. The time necessary for the expression of the adaptive response was also investigated. Materials and Methods: Three lymphoblastoid cell lines from ataxia telangiectasia (AT) homozygote (GM 1526), AT heterozygote (GM 3382), and normal individual (3402p) and two hepatoma cell lines, Hep G2 and Hep 3B, were used in this study. Experiments were carried out by delivering 0.01 Gy followed by 0.5 Gy of gamma radiation to the exponentially growing cells. The time necessary for the expression of the adaptive response was determined by varying the time interval between the two doses from 1 to 72 h. In some experiments, 3-aminobenzamide, a potent inhibitor of poly (ADP-ribose) polymerase, was added immediately after the 0.5 Gy exposure. The cultures were fixed 30 min (for the G 2 chromatid) and 6 h (for the S chromatid) after the 0.5 Gy exposure. Metaphase chromosome assay was carried out to score chromatid breaks as an end point. Results: A prior exposure to 0.01 Gy of gamma rays significantly reduced the number of chromatid breaks induced by subsequent higher doses (0.5 Gy) in all the tested cell lines. The magnitude of the adaptive response was similar among the cell lines despite their different radiosensitivities. In the G 2 chromatids, the adaptive response was observed both at short-time intervals, as early as 1 h, and at long-time intervals. In the S chromatids, however, the adaptive response was shown only at long-time intervals. When 3-aminobenzamide was added after the 0.5 Gy, the adaptive responses were abolished in all the experimental groups. Conclusion: The adaptive response was observed in human lymphoblastoid cell lines and hepatoma cell lines. The magnitude of the adaptive response did not seem to be related to the radiosensitivity of the cells. The elimination of the adaptive response with 3

  2. Adhesion of thymus lymphocytes to aortic endothelial cells in rats irradiated with sup 60 Co-. gamma. -rays

    Energy Technology Data Exchange (ETDEWEB)

    Yongjian, Geng; Zijun, Mao; Zhiwei, Yin [Suzhou Medical Coll., JS (China)

    1990-03-01

    Adhesion of thymus lymphocytes to aortic endothelial cells in Wistar rats irradiated with {sup 60}Co-{gamma}-rays was preliminarily investigated with a stereological method. The results of experiments suggest that the number of lymphocytes of thymus which adhered to aortic endothelial cells significantly (p < 0.01) decreased after irradiation at doses of 2 and 8 Gy. However, when both thymus and aorta were irradiated, there were more lymphocytes adhering to endothelial cells than that when only thymus was irradiated.

  3. The relationship between cell killing, chromosome aberrations, spindle defects, and mitotic delay in mouse lymphoma cells of differential sensitivity to X-rays

    International Nuclear Information System (INIS)

    Scott, D.; Zampetti-Bosseler, F.

    1980-01-01

    A study has been made of the effects of x radiation on an ultrasensitive subline of L5178Y mouse lymphoma cells. It has been shown that at survival levels above about 20 per cent, chromosome structural aberrations which lead to bridges and fragments at anaphase are about four times more frequent than spindle defects. The results demonstrated the higher frequency of structural aberrations and spindle defects, and the greater mitotic delay in the X-ray-sensitive than in the X-ray-resistant cell line. A model is proposed which causally relates these end-points to cell killing and DNA repair. (author)

  4. The aquatic hyphomycete Heliscus lugdunensis protects its hyphae tip cells from cadmium: A micro X-ray fluorescence and X-ray absorption near edge structure spectroscopy study

    Science.gov (United States)

    Isaure, Marie-Pierre; Leyh, Benjamin; Salomé, Murielle; Krauss, Gerd-Joachim; Schaumlöffel, Dirk; Dobritzsch, Dirk

    2017-11-01

    Aquatic fungi can be used to evaluate the functioning of natural ecosystems. Heliscus lugdunensis is an early colonizer of allochthone leafs. Since this aquatic hyphomycete is able to develop in metal contaminated habitats and tolerates cadmium, it appears to be a good candidate to investigate adaptation to metal pollution. This study aimed at examining the sequestration of Cd in the hyphae of H. lugdunensis, and particularly the role of the tip cells. For that, H. lugdunensis growth was evaluated under various Cd concentrations, and a combination of synchrotron micro X-ray fluorescence and X-ray absorption near edge structure spectroscopy was carried out to determine the compartments of Cd accumulation and the Cd chemical species, respectively. Results showed that the hyphal tip cells were depleted in Cd, and that the metal was stored in older cells. Cd was mainly associated with sulfur ligands and to a lesser extent bound to phosphates and carboxyl/hydroxyl groups from cell wall and/or organic acids. Finally, the aquatic fungus was able to maintain the tip cell as a functional system, thus allowing the colonization of contaminated environments.

  5. Irradiation effects of ultraviolet rays on Leptospira cells. Loss of motility, survive ability, and damages of cell structures

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Hidezo (Yamaguchi Univ., Ube (Japan). School of Medicine)

    1982-12-01

    The irradiation effects of ultraviolets rays (UV) on leptospira cells were investigated. Four serovar strains of Genus Leptospira ; L. copenhageni, L. canicola, L. biflexa and L. illini were used. A sterilization lamp (Toshiba-GL-15) was lighted at intervals of 90mm on the sample fluid for several minutes. Loss of motility, survival growth and morphological damages were recognized under several conditions. The medium conditions were important, that is, the Korthof's medium was less effective than phosphate buffered saline (PBS). The irradiation time was also important, that is, L. canicola cells in PBS lost their motility and survive ability within 300sec. of irradiation, however, much more time, such as 1.200sec. was necessary in Korthof's medium. This phenomenon may be depended upon defensibility of albumin in the latter. Among the strains, L. biflexa cells showed the highest resistance in loss of motility and survive ability, and other three strains were inferior. The remarkable efects of cellular structures were also seen in the materials with 30 min. of irradiation, in both immediate time or after 24h incubation. The damages observed after 24th of irradiation were much more drastic than those of immediate time. No effect could be seen on the cells suspended in the Korthof's medium irradiated for 24h. Regarding morphological effect, there appeared relaxation of helical body, spherical body and semighost as the immediate changes. Structural damages were recognized as the collapse of cell body, such as scattering of capsule, release of axial flagella, loss or change of cytoplasmic density and break down of wall membrane complex. These phenomena were regarded as the indirect effects of UV-irradiation and autolysis in a post-mortem change.

  6. Delayed K562 cell apoptosis promoted by cleaved LyGDI after 60Co γ-rays irradiation

    International Nuclear Information System (INIS)

    Sun Huali; Duan Weiming; Shao Yanyan; Xiao Hainan; Zhou Xinwen

    2010-01-01

    Objective: To elucidate the function and regulatory mechanism of LyGDI involved delayed cell death in the human K562 cells and HL-60 cells induced by 60 Co γ-rays. Methods: Erythrosine B cells staining was used to count the apoptosis rate. PI staining and flow cytometry were applied to check the cell cycle. The expression of LYGDI and Rac1 was resolved by Western blot by using monoclonal antibody of LyGDI and Rac1. The distribution of Rac1 protein in cells was observed with immunofluorescence by using the confocal microscope. Results: The K562 cells showed G 2 /M phase arrest and the percent age was 71.3%. The apoptosis rate was very low at early post-irradiation stage in the K562 cells. The apoptosis rate was 14% in the K562 cells at 24 h post-irradiation with 8 Gy of γ-rays, and delayed cell apoptosis was present. LyGDI was cleaved in the K562 cells irradiated by 4 Gy 60 Co γ-rays after 24 hours post-irradiation. The expression of Rac1 protein was not altered at all, but the distribution was changed in the irradiated cells while the Rac1 protein moved to cell membrane and a little in cell nucleus. The Rac1 was activated with the losing the binding affinity with the LyGDI. Conclusion: LyGDI could promote the delayed cell apoptosis, which is through the activation of the Rac1. (authors)

  7. A new 3-D ray tracing method based on LTI using successive partitioning of cell interfaces and traveltime gradients

    Science.gov (United States)

    Zhang, Dong; Zhang, Ting-Ting; Zhang, Xiao-Lei; Yang, Yan; Hu, Ying; Qin, Qian-Qing

    2013-05-01

    We present a new method of three-dimensional (3-D) seismic ray tracing, based on an improvement to the linear traveltime interpolation (LTI) ray tracing algorithm. This new technique involves two separate steps. The first involves a forward calculation based on the LTI method and the dynamic successive partitioning scheme, which is applied to calculate traveltimes on cell boundaries and assumes a wavefront that expands from the source to all grid nodes in the computational domain. We locate several dynamic successive partition points on a cell's surface, the traveltimes of which can be calculated by linear interpolation between the vertices of the cell's boundary. The second is a backward step that uses Fermat's principle and the fact that the ray path is always perpendicular to the wavefront and follows the negative traveltime gradient. In this process, the first-arriving ray path can be traced from the receiver to the source along the negative traveltime gradient, which can be calculated by reconstructing the continuous traveltime field with cubic B-spline interpolation. This new 3-D ray tracing method is compared with the LTI method and the shortest path method (SPM) through a number of numerical experiments. These comparisons show obvious improvements to computed traveltimes and ray paths, both in precision and computational efficiency.

  8. The action of hyperthermia on gene expression in Friend erythroleukemia cells by dimethyl sulfoxide or X-rays

    International Nuclear Information System (INIS)

    Raaphorst, G.P.; Azzam, E.I.; Einspenner, M.; Ewing, D.; Borsa, J.

    1982-02-01

    The effect of heat on gene control and on cell killing by X-rays or dimethyl sulfoxide (DMSO) was studied in cultured Friend erythroleukemia cells (FELC). FELC are very sensitive to heat and X-rays in terms of survival, as measured by the colony-forming assay. Heat inactivation kinetics are similar for FELC and Chinese hamster cells. Thermal enhancement of cell inactivation by irradiation was observed at 42.0 and 45.0deg C, and increased as a function of heating time. The simultaneous application of heat and X-rays had a greater effect in terms of cell inactivation. Dimethyl sulfoxide could induce FELC to synthesize hemoglobin, and hyperthermia could inhibit this response. Likewise, hyperthermia could affect induction of heme synthesis by irradiation. Heating before irradiation enhanced production of heme synthesis, whereas heating after irradiation inhibited induction of heme synthesis. The effects of hyperthermia on the survival and gene induction endpoints were compared. Thus, heat can affect both cell survival and gene induction by irradiation or DMSO. The two endpoints of gene induction and survival (proliferative capacity) responded differently, both quantitatively and qualitatively, to heat and X-rays, implying that different cellular targets are affected for each of these endpoints

  9. In situ liquid water visualization in polymer electrolyte membrane fuel cells with high resolution synchrotron x-ray radiography

    Energy Technology Data Exchange (ETDEWEB)

    Chevalier, S.; Banerjee, R.; Lee, J.; Ge, N.; Lee, C.; Bazylak, A., E-mail: abazylak@mie.utoronto.ca [Dept. of Mechanical & Industrial Engineering, Faculty of Applied Science & Engineering, University of Toronto, Toronto, Ontario (Canada); Wysokinski, T. W.; Belev, G.; Webb, A.; Miller, D.; Zhu, N. [Canadian Light Source, Saskatoon, Saskatchewan (Canada); Tabuchi, Y.; Kotaka, T. [EV System Laboratory, Research Division 2, Nissan Motor Co., Ltd., Yokosuka, Kanagawa (Japan)

    2016-07-27

    In this work, we investigated the dominating properties of the porous materials that impact water dynamics in a polymer electrolyte membrane fuel cell (PEMFC). Visualizations of liquid water in an operating PEMFC were performed at the Canadian Light Source. A miniature fuel cell was specifically designed for X-ray imaging investigations, and an in-house image processing algorithm based on the Beer-Lambert law was developed to extract quantities of liquid water thicknesses (cm) from raw X-ray radiographs. The X-ray attenuation coefficient of water at 24 keV was measured with a calibration device to ensure accurate measurements of the liquid water thicknesses. From this experiment, the through plane distribution of the liquid water in the fuel cell was obtained.

  10. In situ liquid water visualization in polymer electrolyte membrane fuel cells with high resolution synchrotron x-ray radiography

    International Nuclear Information System (INIS)

    Chevalier, S.; Banerjee, R.; Lee, J.; Ge, N.; Lee, C.; Bazylak, A.; Wysokinski, T. W.; Belev, G.; Webb, A.; Miller, D.; Zhu, N.; Tabuchi, Y.; Kotaka, T.

    2016-01-01

    In this work, we investigated the dominating properties of the porous materials that impact water dynamics in a polymer electrolyte membrane fuel cell (PEMFC). Visualizations of liquid water in an operating PEMFC were performed at the Canadian Light Source. A miniature fuel cell was specifically designed for X-ray imaging investigations, and an in-house image processing algorithm based on the Beer-Lambert law was developed to extract quantities of liquid water thicknesses (cm) from raw X-ray radiographs. The X-ray attenuation coefficient of water at 24 keV was measured with a calibration device to ensure accurate measurements of the liquid water thicknesses. From this experiment, the through plane distribution of the liquid water in the fuel cell was obtained.

  11. Studies of Bystander Effect and Intercellular Communication in Human Epithelial Cell Cultures Irradiated with X-rays

    International Nuclear Information System (INIS)

    Romppanen, E.; Trott, K. R.; Musatonen, R.; Leszcznski, D.; Belyakov, O.

    2004-01-01

    The bystander effect is a phenomenon whereby biological consequences of irradiation are expressed in nonexposed cells in the vicinity of exposed cells. Two main pathways have been proposed to mediate the bystander effect: Gap Junction Intercellular Communication (GJIC) and medium borne soluble factors dependent mechanisms. The present study was designed to evaluate the relative contributions of gap junction intercellular communication and of soluble extracellular factors on the bystander effects of low dose X-ray irradiation. HaCaT human epithelial cell monolayers were exposed to X-ray using specially constructed shield, which cover 95% or 56% or 0% of the cells from the radiation. To evaluate whether the GJIC is involved in transmission of the bystander signal from irradiated to nonirradiated cells, irradiations were performed in presence or absence of GJIC inhibitor lindane. The cytochalasin B block technique was used to quantify fractions of micronucleated cells 48 hours after the irradiation. Our results suggest that more micronucleated cells are induced in partially shielded monolayers than expected according to back extrapolation of the data from open field irradiation. Treatment with lindane considerably reduced amount of the bystander damage. We demonstrated that fraction of micronucleated cells after X-rays irradiation of 5% of cells with 1 Gy was 0.07±0.08 (without lindane) and 0.05±0.004 (in presence of lindane). Irradiation of 100% of cells with the same dose resulted in 0.023±0.04 /without lindane) and 0.013±0.02 (in presence of lindane) fractions of micronucleated cells. Comparison with open field data showed that the fraction of micronucleated cells after irradiation of 5% of the cell culture was 5-10 times greater than the estimated fraction assuming no bystander effect. Irradiation of 44% of cells ded not demonstrate a pronounced bystander effect. (Author) 20 refs

  12. DNA damage and the bystander response in tumor and normal cells exposed to X-rays.

    Science.gov (United States)

    Subhashree, M; Venkateswarlu, R; Karthik, K; Shangamithra, V; Venkatachalam, P

    2017-09-01

    Monolayer and suspension cultures of tumor (BMG-1, CCRF-CEM), normal (AG1522, HADF, lymphocytes) and ATM-mutant (GM4405) human cells were exposed to X-rays at doses used in radiotherapy (high dose and high dose-rate) or radiological imaging (low dose and low dose-rate). Radiation-induced DNA damage, its persistence, and possible bystander effects were evaluated, based on DNA damage markers (γ-H2AX, p53 ser15 ) and cell-cycle-specific cyclins (cyclin B1 and cyclin D1). Dose-dependent DNA damage and a dose-independent bystander response were seen after exposure to high dose and high dose-rate radiation. The level of induced damage (expression of p53 ser15 , γ-H2AX) depended on ATM status. However, low dose and dose-rate exposures neither increased expression of marker proteins nor induced a bystander response, except in the CCRF-CEM cells. Bystander effects after high-dose irradiation may contribute to stochastic and deterministic effects. Precautions to protect unexposed regions or to inhibit transmission of DNA damage signaling might reduce radiation risks. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Ion, X-ray, UV and Neutron Microbeam Systems for Cell Irradiation.

    Science.gov (United States)

    Bigelow, A W; Randers-Pehrson, G; Garty, G; Geard, C R; Xu, Y; Harken, A D; Johnson, G W; Brenner, D J

    2010-08-08

    The array of microbeam cell-irradiation systems, available to users at the Radiological Research Accelerator Facility (RARAF), Center for Radiological Research, Columbia University, is expanding. The HVE 5MV Singletron particle accelerator at the facility provides particles to two focused ion microbeam lines: the sub-micron microbeam II and the permanent magnetic microbeam (PMM). Both the electrostatic quadrupole lenses on the microbeam II system and the magnetic quadrupole lenses on the PMM system are arranged as compound lenses consisting of two quadrupole triplets with "Russian" symmetry. Also, the RARAF accelerator is a source for a proton-induced x-ray microbeam (undergoing testing) and is projected to supply protons to a neutron microbeam based on the (7)Li(p, n)(7)Be nuclear reaction (under development). Leveraging from the multiphoton microscope technology integrated within the microbeam II endstation, a UV microspot irradiator - based on multiphoton excitation - is available for facility users. Highlights from radiation-biology demonstrations on single living mammalian cells are included in this review of microbeam systems for cell irradiation at RARAF.

  14. Effects of X-rays on the proliferation dynamics of cells in the imaginal wing disc of Drosophila melanogaster

    Energy Technology Data Exchange (ETDEWEB)

    Haynie, J L; Bryant, P J [California Univ., Irvine (USA). Dept. of Developmental and Cell Biology; California Univ., Irvine (USA). Center for Pathobiology)

    1977-01-01

    The size distribution of clones marked by mitotic recombination induced by several different doses of X-rays applied to 72 h old Drosophila larvae is studied. The results indicate that irradiation significantly reduces the number of cells which undergo normal proliferation in the imaginal wing disc. It is estimated that 1000R reduces by 40-60% the number of cells capable of making a normal contribution to the development of the adult wing. Part of this reduction is due to severe curtailment in the proliferative ability of cells which nevertheless remain capable of adult differentiation: this effect is possibly due to radiation-induced aneuploidy. Cytological evidence suggests that immediate cell death also occurs as a result of radiation doses as low as 100R. The surviving cells are stimulated to undergo additional proliferation in response to the X-ray damage so that the result is the differentiation of a normal wing.

  15. Particle-in-cell simulation of x-ray wakefield acceleration and betatron radiation in nanotubes

    Directory of Open Access Journals (Sweden)

    Xiaomei Zhang

    2016-10-01

    Full Text Available Though wakefield acceleration in crystal channels has been previously proposed, x-ray wakefield acceleration has only recently become a realistic possibility since the invention of the single-cycled optical laser compression technique. We investigate the acceleration due to a wakefield induced by a coherent, ultrashort x-ray pulse guided by a nanoscale channel inside a solid material. By two-dimensional particle-in-cell computer simulations, we show that an acceleration gradient of TeV/cm is attainable. This is about 3 orders of magnitude stronger than that of the conventional plasma-based wakefield accelerations, which implies the possibility of an extremely compact scheme to attain ultrahigh energies. In addition to particle acceleration, this scheme can also induce the emission of high energy photons at ∼O(10–100  MeV. Our simulations confirm such high energy photon emissions, which is in contrast with that induced by the optical laser driven wakefield scheme. In addition to this, the significantly improved emittance of the energetic electrons has been discussed.

  16. Methodological study of aging effects on fuel cells using X-ray synchrotron radiography and tomography

    International Nuclear Information System (INIS)

    Arlt, Tobias

    2012-01-01

    In the present work, new and advanced methods for the investigation of methanol and hydrogen powered fuel cells were analyzed. Synchrotron radiography and tomography were applied to investigate materials and transport processes in operating fuel cells ''in-situ'' and non-destructively. The corrosion of ruthenium is a key issue during aging of direct methanol fuel cells (DMFC). Therefore the influence of different aging processes on the distribution of ruthenium is of great interesting. An imaging method based on X-ray absorption spectroscopy (XAS) was applied to investigate the changes in the distribution of fuel cell catalysts three-dimensionally. Using monoenergetic synchrotron radiation it was shown that the distribution of ruthenium (Ru) in the anode catalyst changes after application of an accelerated aging procedure. A strong influence on the flowfield and the gas diffusion layer structures on the Ru distribution were found in the gas diffusion electrode at the anode side. Additionally some ruthenium moves through the membrane from the anode to the cathode. The redistribution caused by the accelerated aging procedure strongly differs from that obtained after aging under realistic stack operation (here over 1700 h) of a fuel cell in a pallet transporter. For the tomographic investigations samples were taken out from a stack operation in aged membrane electrode assembly (MEA) and were analyzed ex-situ. It was shown that the Ru redistribution can be attributed to mass transport processes (CO 2 and H 2 O) in the gas diffusion layer (GDL). Other high energy resolved measurements showed that the strength of the oxidation of ruthenium and platinum depends on the spatial distribution of the ruthenium. Last mentioned - also for the platinum catalyst - could be given quantitatively by means of this newly developed method. In the second part of this work high temperature polymer electrolyte fuel cells (HT-PEFC) were investigated. No liquid water can

  17. Young gamma-ray pulsar: from modeling the gamma-ray emission to the particle-in-cell simulations of the global magnetosphere

    Science.gov (United States)

    Brambilla, Gabriele; Kalapotharakos, Constantions; Timokhin, Andrey; Kust Harding, Alice; Kazanas, Demosthenes

    2016-04-01

    Accelerated charged particles flowing in the magnetosphere produce pulsar gamma-ray emission. Pair creation processes produce an electron-positron plasma that populates the magnetosphere, in which the plasma is very close to force-free. However, it is unknown how and where the plasma departs from the ideal force-free condition, which consequently inhibits the understanding of the emission generation. We found that a dissipative magnetosphere outside the light cylinder effectively reproduces many aspects of the young gamma-ray pulsar emission as seen by the Fermi Gamma-ray Space Telescope, and through particle-in-cell simulations (PIC), we started explaining this configuration self-consistently. These findings show that, together, a magnetic field structure close to force-free and the assumption of gamma-ray curvature radiation as the emission mechanism are strongly compatible with the observations. Two main issues from the previously used models that our work addresses are the inability to explain luminosity, spectra, and light curve features at the same time and the inconsistency of the electrodynamics. Moreover, using the PIC simulations, we explore the effects of different pair multiplicities on the magnetosphere configurations and the locations of the accelerating regions. Our work aims for a self-consistent modeling of the magnetosphere, connecting the microphysics of the pair-plasma to the global magnetosphere macroscopic quantities. This direction will lead to a greater understanding of pulsar emission at all wavelengths, as well as to concrete insights into the physics of the magnetosphere.

  18. Repair of soft X-ray damage to mammalian cell DNA

    Energy Technology Data Exchange (ETDEWEB)

    Meldrum, R.A.; Wharton, C.W. (Birmingham Univ. (UK). Dept. of Biochemistry)

    1990-10-01

    Inhibitors of polymerase {alpha} (hydroxyurea and cytosine arabinoside) and an inhibitor of polymerase {beta} and ''delta (di-deoxythymidine) had equal inhibitory effects on repair synthesis in the first 15 min after irradiation of Chinese hamster ovary cells with soft x-rays produced from a laser plasma. Polymerase {alpha} inhibitors had considerably more effect after 15 min following irradiation. This implies that polymerase {alpha}, {beta}, and/or {delta} are all equally active in the initial stages of repair synthesis after soft X-radiation, but {alpha}-activity is more prominent in later stages of repair synthesis. Polymerase {alpha} is thought to catalyse long-patch repair synthesis, while polymerase {beta} is thought to catalyse short-patch repair. Polymerase {delta} has been shown to be active in DNA repair synthesis, but its precise function is as yet uncertain. (author).

  19. In-situ X-ray Nanocharacterization of Defect Kinetics in Chalcogenide Solar Cell Materials

    Energy Technology Data Exchange (ETDEWEB)

    Bertoni, Mariana [Arizona State Univ., Tempe, AZ (United States); Lai, Barry [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Masser, Jorg [Argonne National Lab. (ANL), Argonne, IL (United States). Advanced Photon Source (APS); Buonassisi, Tonio [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2016-09-21

    For decades the optimization of polycrystalline absorbers has been done using an Edisonian approach, where trial and error and complex design of experiments in large parameter spaces have driven efficiencies to the record values we see today – CIGS at 22.5%, 22.1% for CdTe, 21.3% for high purity multi-crystalline silicon. Appropriate growth parameters are critical to ensure good quality crystals with low concentration of structural defects - low dislocation density and large grain sizes. However, to bridge the gap between the efficiencies today and the fundamental Shockley-Queisser limit for these materials a much more fundamental understanding of the role and interaction between composition, structure, defect density and electrical properties is required. In recent years multiple novel characterization techniques have shown the potential that nanoscale characterization can have in deciphering the composition of grain boundaries in materials like CIGS and CdTe. However, high resolution has come at the cost of small sampling areas and number of specimens, making it extremely difficult to draw conclusions based on the characteristic small sampling sizes. The missing links thus far have been: (1) the lack of statistical meaningfulness of the nanosclae studies and (2) the direct correlation of compositional variations to electrical performance with nanoscale resolution. In this work we present the use of synchrotron-based nano-X-ray fluorescence microscopy (nano-XRF), x-ray absorption nanospectroscopy (nano-XAS) coupled with nano-x-ray beam induced current (nano-XBIC) as ideal tools for investigating elemental, chemical and electrical properties of large areas of solar cell materials at the sub-micron scale with very high sensitivity. We show how the technique can provide statistical valuable information regarding the elemental segregation in CIGS and the direct correlation to current collection. For example, we demonstrate that Cu and Ga (and with that, CGI and GGI

  20. Parkinson's disease and Alzheimer's disease: hypersensitivity to X-rays in cultured cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Robbins, J H; Otsuka, Fujio; Tarone, R E; Polinsky, R J; Nee, L E; Brumback, R A

    1985-09-01

    Fibroblast and/or lymphoblastoid lines from patients with several inherited primary neuronal degenerations are hypersensitive to DNA-damaging agents. Therefore, lymphoblastoid lines were irradiated from patients with sporadic Parkinson's disease (PD), Alzheimer's disease, and amyotrophic lateral sclerosis. The mean survival values of the eight Parkinson's disease and of the six Alzheimer's disease lines, but not of the five amyotrophic lateral sclerosis lines, were less than that of the 28 normal lines. Our results with Parkinson's disease and Alzheimer's disease cells can be explained by a genetic defect arising as a somatic mutation during embryogenesis, causing defective repair of the X-ray type of DNA damage. Such a DNA repair defect could cause an abnormal accumulation of spontaneously occurring DNA damage in Parkinson's disease and Alzheimer's disease neurons in vivo, resulting in their premature death.

  1. Parkinson's disease and Alzheimer's disease: hypersensitivity to X-rays in cultured cell lines

    International Nuclear Information System (INIS)

    Robbins, J.H.; Otsuka, Fujio; Tarone, R.E.; Polinsky, R.J.; Nee, L.E.; Brumback, R.A.

    1985-01-01

    Fibroblast and/or lymphoblastoid lines from patients with several inherited primary neuronal degenerations are hypersensitive to DNA-damaging agents. Therefore, lymphoblastoid lines were irradiated from patients with sporadic Parkinson's disease (PD), Alzheimer's disease, and amyotrophic lateral sclerosis. The mean survival values of the eight Parkinson's disease and of the six Alzheimer's disease lines, but not of the five amyotrophic lateral sclerosis lines, were less than that of the 28 normal lines. Our results with Parkinson's disease and Alzheimer's disease cells can be explained by a genetic defect arising as a somatic mutation during embryogenesis, causing defective repair of the X-ray type of DNA damage. Such a DNA repair defect could cause an abnormal accumulation of spontaneously occurring DNA damage in Parkinson's disease and Alzheimer's disease neurons in vivo, resulting in their premature death. (author)

  2. Radiosensitizing effect of nitric oxide in tumor cells and experimental tumors irradiated with gamma rays and proton beams

    International Nuclear Information System (INIS)

    Policastro, Lucia L.; Duran, Hebe; Molinari, Beatriz L.; Somacal, Hector R.; Valda, Alejandro A.

    2003-01-01

    Nitric oxide (NO) has been reported to be a radiosensitizer of mammalian cells under hypoxic conditions. In a previous study, we demonstrated an enhancement in radiation response induced by NO in mouse tumor cells under aerobic conditions, with an increasing effect as a function of malignancy. The aim of the present study was to evaluate the effect of NO in tumor cells and in experimental tumors irradiated with γ rays and proton beams. Irradiations were performed with a 137 Cs γ source and with proton beams generated by the TANDAR accelerator. Tumor cells were treated with the NO donor DETA-NO and the sensitizer enhancement ratio (SER) was calculated using the α parameter of the survival curve fitted to the linear-quadratic model. Tumor cells irradiated with protons were radio sensitized by DETA-NO only in the more malignant cells irradiated with low LET protons (2.69±0.08 keV/μm). For higher LET protons there were no radiosensitizing effect. For human tumor cells pre-treated with DETA-NO and irradiated with γ rays, a significantly greater effect was demonstrated in the malignant cells (MCF-7) as compared with the near normal cells (HBL-100). Moreover, a significant decrease in tumor growth was demonstrated in mice pre-treated with the NO donor spermine and irradiated with γ rays and low LET protons as compared with mice irradiated without pre-treatment with the NO donor. In conclusion, we demonstrated a differential effect of NO as a radiosensitizer of malignant cells, both with γ rays and low LET protons. This selectivity, coupled to the in vivo inhibition of tumor growth, is of great interest for the potential use of NO releasing agents in radiotherapy. (author)

  3. Cloning of smac gene and its overexpression effects on radiosensitivity of HeLa cells to γ-rays

    International Nuclear Information System (INIS)

    Zhao Baofeng; Tian Mei; Lei Hongwei; Su Xu

    2006-01-01

    Objective: To clone smac gene and construct eukaryocytic expression vector pcDNA3.1/ smac. The smac gene was transfected into HeLa cells to explore the effects of over-expression of extrinsic smac gene on radiosensitivity to γ-rays of HeLa cells. Methods: The full-length smac gene was amplified from total RNA of HeLa cells by RTPCR. The RTPCR product was ligated with the vector pcDNA3.1 and sequenced. The correct pcDNA3.1/smac was transfected into HeLa cells. The expression of smac gene was tested by RTPCR and Western blot. The cellular growth inhibition rates were evaluated by MTT 48 horns after irradiation with different doses of γ-rays. Results: Recombinant eukaryocytic expression vector pcDNA3.1/smac was successfully constructed. RTPCR and Western blot results indicated that the expression of smac gene of HeLa/smac cells was significantly enhanced compared with the expression of smac gene of HeLa/pcDNA3.1 and HeLa cells. 48 hours after different doses of γ-ray irradiation was significantly higher in pcDNA3.1/smac transfected HeLa/smac cells than those of non-transfected HeLa cells or pcDNA3.1 transfected HeLa/pcDNA3.1 cells, inhabitation rates were 38.85%, 17.64% and 20.32%, respectively. Conclusions: smac gene was successfully cloned. Extrinsic smac gene over-expression could significantly enhance radiosensitivity to γ-ray of HeLa cells, which would herald a new approach to improve radiosensitivity of cervical cancer. (authors)

  4. A reaction cell with sample laser heating for in situ soft X-ray absorption spectroscopy studies under environmental conditions.

    Science.gov (United States)

    Escudero, Carlos; Jiang, Peng; Pach, Elzbieta; Borondics, Ferenc; West, Mark W; Tuxen, Anders; Chintapalli, Mahati; Carenco, Sophie; Guo, Jinghua; Salmeron, Miquel

    2013-05-01

    A miniature (1 ml volume) reaction cell with transparent X-ray windows and laser heating of the sample has been designed to conduct X-ray absorption spectroscopy studies of materials in the presence of gases at atmospheric pressures. Heating by laser solves the problems associated with the presence of reactive gases interacting with hot filaments used in resistive heating methods. It also facilitates collection of a small total electron yield signal by eliminating interference with heating current leakage and ground loops. The excellent operation of the cell is demonstrated with examples of CO and H2 Fischer-Tropsch reactions on Co nanoparticles.

  5. Differential Bystander Signaling Between Radioresistant Chondrosarcoma Cells and Fibroblasts After X-Ray, Proton, Iron Ion and Carbon Ion Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Wakatsuki, Masaru, E-mail: wa@mbe.nifty.com [Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, Chiba (Japan); Department of Radiation Oncology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts (United States); Magpayo, Nicole; Kawamura, Hidemasa; Held, Kathryn D. [Department of Radiation Oncology, Massachusetts General Hospital/Harvard Medical School, Boston, Massachusetts (United States)

    2012-09-01

    Purpose: Chondrosarcoma is well known as a radioresistant tumor, but the mechanisms underlying that resistance are still unclear. The bystander effect is well documented in the field of radiation biology. We investigated the bystander response induced by X-rays, protons, carbon ions, and iron ions in chondrosarcoma cells using a transwell insert co-culture system that precludes physical contact between targeted and bystander cells. Methods and Materials: Human chondrosarcoma cells were irradiated with 0.1-, 0.5-, 1-, and 2-Gy X-rays, protons, carbon ions or iron ions using a transwell insert co-culture system. Formation of micronuclei and p53 binding protein 1 staining in bystander and irradiated cells were analyzed and bystander signaling between mixed cultures of chondrosarcoma cells, and normal human skin fibroblasts was investigated. Results: In this study, we show that the fraction of cells with DNA damages in irradiated chondrosarcoma cells showed dose-dependent increases with all beams. However, the fraction of cells with DNA damages in all bystander chondrosarcoma cells did not show any change from the levels in control cells. In the bystander signaling between mixed cultures of chondrosarcoma cells and fibroblasts, the amount of micronucleus formation in all bystander chondrosarcoma cells co-cultured with irradiated fibroblasts were the same as the levels for control cells. However, all bystander fibroblasts co-cultured with irradiated chondrosarcoma cells showed significant increases in the fraction of micronucleated cells compared to the rate of control cells. Conclusions: We conclude that chondrosarcoma cells in the transwell insert co-culture system could release bystander stimulations but could not develop bystander responses.

  6. Differential Bystander Signaling Between Radioresistant Chondrosarcoma Cells and Fibroblasts After X-Ray, Proton, Iron Ion and Carbon Ion Exposures

    International Nuclear Information System (INIS)

    Wakatsuki, Masaru; Magpayo, Nicole; Kawamura, Hidemasa; Held, Kathryn D.

    2012-01-01

    Purpose: Chondrosarcoma is well known as a radioresistant tumor, but the mechanisms underlying that resistance are still unclear. The bystander effect is well documented in the field of radiation biology. We investigated the bystander response induced by X-rays, protons, carbon ions, and iron ions in chondrosarcoma cells using a transwell insert co-culture system that precludes physical contact between targeted and bystander cells. Methods and Materials: Human chondrosarcoma cells were irradiated with 0.1-, 0.5-, 1-, and 2-Gy X-rays, protons, carbon ions or iron ions using a transwell insert co-culture system. Formation of micronuclei and p53 binding protein 1 staining in bystander and irradiated cells were analyzed and bystander signaling between mixed cultures of chondrosarcoma cells, and normal human skin fibroblasts was investigated. Results: In this study, we show that the fraction of cells with DNA damages in irradiated chondrosarcoma cells showed dose-dependent increases with all beams. However, the fraction of cells with DNA damages in all bystander chondrosarcoma cells did not show any change from the levels in control cells. In the bystander signaling between mixed cultures of chondrosarcoma cells and fibroblasts, the amount of micronucleus formation in all bystander chondrosarcoma cells co-cultured with irradiated fibroblasts were the same as the levels for control cells. However, all bystander fibroblasts co-cultured with irradiated chondrosarcoma cells showed significant increases in the fraction of micronucleated cells compared to the rate of control cells. Conclusions: We conclude that chondrosarcoma cells in the transwell insert co-culture system could release bystander stimulations but could not develop bystander responses.

  7. Real-time observation of irradiated Hela-cell Modified by Fluorescent ubiquitination-based Cell Cycle Indicator Using Synchrotron X-Ray Microbeam

    International Nuclear Information System (INIS)

    Narita, A.; Noguchi, M.; Kaminaga, K.; Yokoya, A.; Kobayashi, K.; Usami, N.; Fujii, K.

    2015-01-01

    Fluorescent ubiquitination-based cell-cycle indicator (FUCCI) human cancer (HeLa) cells (red indicates G1; green, S/G2) were exposed to a synchrotron X-ray microbeam. Cells in either G1 or S/G2 were irradiated selectively according to their colour in the same microscopic field. Time-lapse micrographs of the irradiated cells were acquired for 24 h after irradiation. For fluorescent immunostaining, phosphorylated histone proteins (γ-H2AX) indicated the induction of DNA double-strand breaks. The cell cycle was arrested by irradiation at S/G2. In contrast, cells irradiated at G1 progressed to S/G2. The foci were induced in cells irradiated at both G1 and S/G2, suggesting that the G1-S (or S) checkpoint pathway does not function in HeLa cells due to the fact that the cells are functionally p53 deficient, even though X-ray microbeam irradiation significantly induces double-strand breaks. These results demonstrate that single FUCCI cell exposure and live cell imaging are powerful methods for studying the effects of radiation on the cell cycle. (authors)

  8. Oil and mucilage cells in Annona (Annonaceae) and their systematic significance

    NARCIS (Netherlands)

    Bakker, M.E.; Gerritsen, A.F.

    1992-01-01

    The morphology and distribution patterns of oil and/or mucilage cells, i.e. idioblasts, in the leaf of 37 Annona species are described. Idioblasts are always present in the spongy parenchyma in all species and in most cases also in the palisade parenchyma. Usually both oil cells and mucilage cells

  9. Single source dual energy CT: What is the optimal monochromatic energy level for the analysis of the lung parenchyma?

    Energy Technology Data Exchange (ETDEWEB)

    Ohana, M., E-mail: mickael.ohana@gmail.com [iCube Laboratory, Université de Strasbourg/CNRS, UMR 7357, 67400 Illkirch (France); Service de Radiologie B, Nouvel Hôpital Civil – Hôpitaux Universitaires de Strasbourg, 1 place de l’hôpital, 67000 Strasbourg (France); Labani, A., E-mail: aissam.labani@chru-strasbourg.fr [Service de Radiologie B, Nouvel Hôpital Civil – Hôpitaux Universitaires de Strasbourg, 1 place de l’hôpital, 67000 Strasbourg (France); Severac, F., E-mail: francois.severac@chru-strasbourg.fr [Département de Biostatistiques et d’Informatique Médicale, Hôpital Civil – Hôpitaux Universitaires de Strasbourg,1 place de l’hôpital, 67000 Strasbourg (France); Jeung, M.Y., E-mail: Mi-Young.Jeung@chru-strasbourg.fr [Service de Radiologie B, Nouvel Hôpital Civil – Hôpitaux Universitaires de Strasbourg, 1 place de l’hôpital, 67000 Strasbourg (France); Gaertner, S., E-mail: Sebastien.Gaertner@chru-strasbourg.fr [Service de Médecine Vasculaire, Nouvel Hôpital Civil – Hôpitaux Universitaires de Strasbourg,1 place de l’hôpital, 67000 Strasbourg (France); and others

    2017-03-15

    Highlights: • Lung parenchyma aspect varies with the monochromatic energy level in spectral CT. • Optimal diagnostic and image quality is obtained at 50–55 keV. • Mediastinum and parenchyma could be read on the same monochromatic energy level. - Abstract: Objective: To determine the optimal monochromatic energy level for lung parenchyma analysis in spectral CT. Methods: All 50 examinations (58% men, 64.8 ± 16yo) from an IRB-approved prospective study on single-source dual energy chest CT were retrospectively included and analyzed. Monochromatic images in lung window reconstructed every 5 keV from 40 to 140 keV were independently assessed by two chest radiologists. Based on the overall image quality and the depiction/conspicuity of parenchymal lesions, each reader had to designate for every patient the keV level providing the best diagnostic and image quality. Results: 72% of the examinations exhibited parenchymal lesions. Reader 1 picked the 55 keV monochromatic reconstruction in 52% of cases, 50 in 30% and 60 in 18%. Reader 2 chose 50 keV in 52% cases, 55 in 40%, 60 in 6% and 40 in 2%. The 50 and 55 keV levels were chosen by at least one reader in 64% and 76% of all patients, respectively. Merging 50 and 55 keV into one category results in an optimal setting selected by reader 1 in 82% of patients and by reader 2 in 92%, with a 74% concomitant agreement. Conclusion: The best image quality for lung parenchyma in spectral CT is obtained with the 50–55 keV monochromatic reconstructions.

  10. Infarction and Laceration of Liver Parenchyma Caused by Wedged CO{sub 2} Venography Before TIPS Insertion

    Energy Technology Data Exchange (ETDEWEB)

    Theuerkauf, Ingo [Department of Pathology, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany); Strunk, Holger [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany); Brensing, Karl August [Department of Internal Medicine, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany); Schild, Hans Heinz [Department of Radiology, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany); Pfeifer, Ulrich [Department of Pathology, University of Bonn, Sigmund-Freud-Strasse 25, D-53127 Bonn (Germany)

    2001-01-15

    We describe the fatal outcome of an elective TIPS procedure performed in a 43-year-old man with alcoholic cirrhosis. Wedged hepatic venography with CO{sub 2} was the reason for infarction and laceration of liver parenchyma resulting in a subcapsular hematoma and subsequent intra-abdominal bleeding. This is the first report of this complication after the use of CO{sub 2} in a cirrhotic patient.

  11. Effects of X-ray irradiation on expression of Pokemon gene in A549 cells of human lung adenocarcinoma

    International Nuclear Information System (INIS)

    Wang Lu; Zou Yue; Jiang Qisheng; Li Wei; Song Xiujun; Zhou Xiangyan; Wang Cuilan

    2011-01-01

    Objective: To study the dose-and time-effects of X-ray irradiation on the expression of Pokemon gene in A549 cells of human lung adenocarcinoma. Methods: A549 cells were cultured in vitro and exposed to X-rays with the doses of 2, 4, 6 and 8 Gy, respectively. Untreated A549 cells were used as control group. The relative levels of Pokemon mRNA expression in the cells were detected by using quantitative real-time PCR at 2, 4, 8, 12, 24, 48 and 72 h after irradiation. Results: The Pokemon mRNA expression levels decreased in the early period after irradiation (except 2 and 4 h after irradiation in 2 Gy group) and then increased in the later stage (48 h after irradiation) with significant statistical differences at the most time points in comparison with the control group (t=3.40-154.76, P<0.05). Conclusions: Higher doses of X-rays may degrade the expression of Pokemon mRNA in the human A549 cells and induce apoptosis in the early period, hut also may upgrade its expression in the later period, which might be correlated with the cell cycle regulation and DNA damage repair in the A549 cells. (authors)

  12. CT perfusion of the liver during selective hepatic arteriography. Pure arterial blood perfusion of liver tumor and parenchyma

    International Nuclear Information System (INIS)

    Komemushi, Atsushi; Tanigawa, Noboru; Kojima, Hiroyuki; Kariya, Shuji; Sawada, Satoshi

    2003-01-01

    The purpose of this study was to quantify pure arterial blood perfusion of liver tumor and parenchyma by using CT perfusion during selective hepatic arteriography. A total of 44 patients underwent liver CT perfusion study by injection of contrast medium via the hepatic artery. CT-perfusion parameters including arterial blood flow, arterial blood volume, and arterial mean transit time in the liver parenchyma and liver tumor were calculated using the deconvolution method. The CT-perfusion parameters and vascularity of the tumor were compared. A complete analysis could be performed in 36 of the 44 patients. For liver tumor and liver parenchyma, respectively, arterial blood flow was 184.6±132.7 and 41.0±27.0 ml/min/100 g, arterial blood volume was 19.4±14.6 and 4.8±4.2 ml/100 g, and arterial mean transit time was 8.9±4.2 and 10.2±5.3 sec. Arterial blood flow and arterial blood volume correlated significantly with the vascularity of the tumor; however no correlation was detected between arterial mean transit time and the vascularity of the tumor. This technique could be used to quantify pure hepatic arterial blood perfusion. (author)

  13. Pulmonary parenchyma segmentation in thin CT image sequences with spectral clustering and geodesic active contour model based on similarity

    Science.gov (United States)

    He, Nana; Zhang, Xiaolong; Zhao, Juanjuan; Zhao, Huilan; Qiang, Yan

    2017-07-01

    While the popular thin layer scanning technology of spiral CT has helped to improve diagnoses of lung diseases, the large volumes of scanning images produced by the technology also dramatically increase the load of physicians in lesion detection. Computer-aided diagnosis techniques like lesions segmentation in thin CT sequences have been developed to address this issue, but it remains a challenge to achieve high segmentation efficiency and accuracy without much involvement of human manual intervention. In this paper, we present our research on automated segmentation of lung parenchyma with an improved geodesic active contour model that is geodesic active contour model based on similarity (GACBS). Combining spectral clustering algorithm based on Nystrom (SCN) with GACBS, this algorithm first extracts key image slices, then uses these slices to generate an initial contour of pulmonary parenchyma of un-segmented slices with an interpolation algorithm, and finally segments lung parenchyma of un-segmented slices. Experimental results show that the segmentation results generated by our method are close to what manual segmentation can produce, with an average volume overlap ratio of 91.48%.

  14. A comparisonof lymphocytic thyroiditis with papillary thyroid carcinoma showing suspicious ultrasonographic findings in a background of heterogeneous parenchyma

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Sang Yu; Shin, Jung Hee; Ko, Eun Young; Hahn, Soo Yeon [Dept. of Radiology, Samsung Medicine Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2015-01-15

    The aim of this study was to compare ultrasonographic features in patients with lymphocytic thyroiditis (LT) and papillary thyroid carcinoma (PTC) having suspicious thyroid nodule(s) in a background of heterogeneous parenchyma and to determine the clinical and radiological predictors of malignancy. We reviewed the cases of 100 patients who underwent ultrasonography between April 2011 and October 2012, and showed suspicious thyroid nodule(s) in a background of heterogeneous parenchyma. Eight patients who did not undergo ultrasonography-guided fineneedle aspiration cytology (FNAC) and 34 cases of follow-up ultrasonography after initial FNAC were excluded. We compared the benign and malignant nodules in terms of their clinical and radiological factors. For the 58 nodules including 31 LTs (53.4%) and 27 PTCs (46.6%), the mean tumor sizes of the two groups were 0.96 cm for LT and 0.97 cm for PTC. A univariate analysis revealed that PTCs were more frequent in patients younger than 45 years and having microcalcifications than was LT. An independent predictor of PTC after adjustment was an age of <45 years. LT mimics malignancy in a background of heterogeneous parenchyma on ultrasonography. A young age of <45 years is the most important predictor of malignancy in this condition.

  15. Ultrasound-mediated delivery and distribution of polymeric nanoparticles in the normal brain parenchyma of a metastatic brain tumour model.

    Directory of Open Access Journals (Sweden)

    Habib Baghirov

    Full Text Available The treatment of brain diseases is hindered by the blood-brain barrier (BBB preventing most drugs from entering the brain. Focused ultrasound (FUS with microbubbles can open the BBB safely and reversibly. Systemic drug injection might induce toxicity, but encapsulation into nanoparticles reduces accumulation in normal tissue. Here we used a novel platform based on poly(2-ethyl-butyl cyanoacrylate nanoparticle-stabilized microbubbles to permeabilize the BBB in a melanoma brain metastasis model. With a dual-frequency ultrasound transducer generating FUS at 1.1 MHz and 7.8 MHz, we opened the BBB using nanoparticle-microbubbles and low-frequency FUS, and applied high-frequency FUS to generate acoustic radiation force and push nanoparticles through the extracellular matrix. Using confocal microscopy and image analysis, we quantified nanoparticle extravasation and distribution in the brain parenchyma. We also evaluated haemorrhage, as well as the expression of P-glycoprotein, a key BBB component. FUS and microbubbles distributed nanoparticles in the brain parenchyma, and the distribution depended on the extent of BBB opening. The results from acoustic radiation force were not conclusive, but in a few animals some effect could be detected. P-glycoprotein was not significantly altered immediately after sonication. In summary, FUS with our nanoparticle-stabilized microbubbles can achieve accumulation and displacement of nanoparticles in the brain parenchyma.

  16. Transtemporal Investigation of Brain Parenchyma Elasticity Using 2-D Shear Wave Elastography: Definition of Age-Matched Normal Values.

    Science.gov (United States)

    Ertl, Michael; Raasch, Nele; Hammel, Gertrud; Harter, Katharina; Lang, Christopher

    2018-01-01

    The goal of our research was to assess the possibility of reliable investigation of brain tissue stiffness using ultrasonographic brain parenchyma elastography with an intact temporal bone. We enrolled 108 patients after exclusion of intracranial pathology or healthy volunteers. All patients were subdivided by age into groups: 20-40, 40-60 and >60 y. For statistical analysis, the χ 2 test and t-test were used. The mean values, regardless of age and other parameters, were 3.34 kPa (SD = 0.59) on the left side and 3.33 kPa (SD = 0.58) on the right side. We found no correlation between the values, body mass index (r = 0.07, p = 0.48) and sex (t = -0.11, p = 0.91), but we observed a highly significant correlation between the values and age (r = 0.43, p <0.0001). We found ultrasonographic brain parenchyma elastography to be a valid, reproducible and investigator-independent method that reliably determines brain parenchyma stiffness. Normal values should serve as a reference for studies on various intracranial lesions. Copyright © 2018 World Federation for Ultrasound in Medicine and Biology. Published by Elsevier Inc. All rights reserved.

  17. Ultrasound-mediated delivery and distribution of polymeric nanoparticles in the normal brain parenchyma of a metastatic brain tumour model

    Science.gov (United States)

    Baghirov, Habib; Snipstad, Sofie; Sulheim, Einar; Berg, Sigrid; Hansen, Rune; Thorsen, Frits; Mørch, Yrr; Åslund, Andreas K. O.

    2018-01-01

    The treatment of brain diseases is hindered by the blood-brain barrier (BBB) preventing most drugs from entering the brain. Focused ultrasound (FUS) with microbubbles can open the BBB safely and reversibly. Systemic drug injection might induce toxicity, but encapsulation into nanoparticles reduces accumulation in normal tissue. Here we used a novel platform based on poly(2-ethyl-butyl cyanoacrylate) nanoparticle-stabilized microbubbles to permeabilize the BBB in a melanoma brain metastasis model. With a dual-frequency ultrasound transducer generating FUS at 1.1 MHz and 7.8 MHz, we opened the BBB using nanoparticle-microbubbles and low-frequency FUS, and applied high-frequency FUS to generate acoustic radiation force and push nanoparticles through the extracellular matrix. Using confocal microscopy and image analysis, we quantified nanoparticle extravasation and distribution in the brain parenchyma. We also evaluated haemorrhage, as well as the expression of P-glycoprotein, a key BBB component. FUS and microbubbles distributed nanoparticles in the brain parenchyma, and the distribution depended on the extent of BBB opening. The results from acoustic radiation force were not conclusive, but in a few animals some effect could be detected. P-glycoprotein was not significantly altered immediately after sonication. In summary, FUS with our nanoparticle-stabilized microbubbles can achieve accumulation and displacement of nanoparticles in the brain parenchyma. PMID:29338016

  18. Phase-based x-ray scattering—A possible method to detect cancer cells in a very early stage

    Energy Technology Data Exchange (ETDEWEB)

    Feye-Treimer, U., E-mail: feye-treimer@helmholtz-berlin.de; Treimer, W. [Department of Mathematics, Physics and Chemistry, University of Applied Sciences, D-13353 Berlin, Germany and Joint Department G-GTOMO, Helmholtz Zentrum fuer Materialien und Energie Berlin, D-14109 Berlin (Germany)

    2014-05-15

    Purpose: This theoretical work contains a detailed investigation of the potential and sensitivity of phase-based x-ray scattering for cancer detection in biopsies if cancer is in a very early stage of development. Methods: Cancer cells in their early stage of development differ from healthy ones mainly due to their faster growing cell nuclei and the enlargement of their densities. This growth is accompanied by an altered nucleus–plasma relation for the benefit of the cell nuclei, that changes the physical properties especially the index of refraction of the cell and the one of the cell nuclei. Interaction of radiation with matter is known to be highly sensitive to small changes of the index of refraction of matter; therefore a detection of such changes of volume and density of cell nuclei by means of high angular resolved phase-based scattering of x rays might provide a technique to distinguish malignant cells from healthy ones ifthe cell–cell nucleus system is considered as a coherent phase shifting object. Then one can observe from a thin biopsy which represents a monolayer of cells (no multiple scattering) that phase-based x-ray scattering curves from healthy cells differ from those of cancer cells in their early stage of development. Results: Detailed calculations of x-ray scattering patterns from healthy and cancer cell nuclei yield graphs and numbers with which one can distinguish healthy cells from cancer ones, taking into account that both kinds of cells occur in a tissue within a range of size and density. One important result is the role and the influence of the (lateral) coherence width of the radiation on the scattering curves and the sensitivity of phase-based scattering for cancer detection. A major result is that a larger coherence width yields a larger sensitivity for cancer detection. Further import results are calculated limits for critical sizes and densities of cell nuclei in order to attribute the investigated tissue to be healthy or

  19. Study of HeLa cells clone survival after X-ray irradiation in the presence of cisplatin

    Science.gov (United States)

    Baulin, A. A.; Sukhikh, E. S.; Vasilyev, S. A.; Sukhikh, L. G.; Sheino, I. N.

    2017-09-01

    Radiation therapy in the presence of heavy elements nuclei (Z > 53) is widely developed these days. The presence of such nuclei in cancer cells results in the local increase of energy release from primary photon beam thus increasing relative biological efficiency. In this paper we present the preliminary results of the cell survival study while irradiating cells by X-Ray photon beam in the presence of cisplatin (Pt, Z = 78). The preliminary results show the decrease of the cell survival in the presence of both radiation and cisplatin.

  20. Enhancement of cell death by TNF α-related apoptosis-inducing ligand (TRAIL) in human lung carcinoma A549 cells exposed to X rays under hypoxia

    International Nuclear Information System (INIS)

    Takahashi, Momoko; Inanami, Osamu; Yasui, Hironobu; Ogura, Aki; Kuwabara, Mikinori; Kubota, Nobuo; Tsujitani, Michihiko

    2007-01-01

    Our previous study showed that ionizing radiation induced the expression of death receptor DR5 on the cell surface in tumor cell lines and that the death receptor of the TNF α-related apoptosis-inducing ligand TRAIL enhanced the apoptotic pathway (Hamasu et al., (2005) Journal of Radiation Research, 46:103-110). The present experiments were performed to examine whether treatment with TRAIL enhanced the cell killing in tumor cells exposed to ionizing radiation under hypoxia, since the presence of radioresistant cells in hypoxic regions of solid tumors is a serious problem in radiation therapy for tumors. When human lung carcinoma A549 cells were irradiated under normoxia and hypoxia, respectively, radiation-induced enhancement of expression of DR5 was observed under both conditions. Incubation in the presence of TRAIL enhanced the caspase-dependent and chymotrypsin-like-protease-dependent apoptotic cell death in A549 cells exposed to X rays. Furthermore, it was shown that treatment with TRAIL enhanced apoptotic cell death and loss of clonogenic ability in A549 cells exposed to X rays not only under normoxia but also under hypoxia, suggesting that combination treatment with TRAIL and X irradiation is effective for hypoxic tumor cells. (author)

  1. Fractionated dose studies with X-rays and various alkylating agents in P388 mouse lymphoma cells

    International Nuclear Information System (INIS)

    Anderson, D.

    1981-01-01

    The fractionated dose technique has been used in P388F cells to examine the effects of X-rays and four alkylating agents on survival and induction of 5-iodo-2-deoxyuridine (IudR) resistant variants. Fractionation intervals up to 5 1/2 h were used for X-rays and for the alkylating agents up to 192 h. Fractionation of the X-ray dose resulted in a sparing effect for survival and variant induction. A sparing effect was also observed for survival after treatment with alkylating agents. However, variant frequencies were observed as large as or greater than those produced by the full doses of alkylating agents. For such agents this would suggest that survival and variant induction are independent events. Differences in the effects of X-rays and alkylating agents cannot be explained by differences in growth rate or the recovery of viability after treatment

  2. Fractionated dose studies with X-rays and various alkylating agents in P388 mouse lymphoma cells

    International Nuclear Information System (INIS)

    Anderson, D.

    1981-01-01

    The fractionated dose technique was used in P388F cells to examine the effects of X-rays and four alkylating agents on survival and induction of 5-iodo-2-deoxyuridine (IudR) resistant variants. Fractionation intervals up to 51/2 h were used for X-rays and for the alkylating agents up to 192 h. Fractionation of the X-ray dose resulted in a sparing effect for survival and variant induction. A sparing effect was also observed for survival after treatment with alkylating agents. However, variant frequencies were observed as large as or greater than those produced by the full doses of alkylating agents. For such agents this would suggest that survival and variant induction are independent events. Differences in the effects of X-rays and alkylating agents cannot be explained by differences in growth rate or the recovery of viability after treatment. (author)

  3. A sealable ultrathin window sample cell for the study of liquids by means of soft X-ray spectroscopy

    Science.gov (United States)

    Grötzsch, D.; Streeck, C.; Nietzold, C.; Malzer, W.; Mantouvalou, I.; Nutsch, A.; Dietrich, P.; Unger, W.; Beckhoff, B.; Kanngießer, B.

    2017-12-01

    A new sample cell concept for the analysis of liquids or solid-liquid interfaces using soft X-ray spectroscopy is presented, which enables the complete sealing of the cell as well as the transport into vacuum via, for example, a load-lock system. The cell uses pressure monitoring and active as well as passive pressure regulation systems, thereby facilitating the full control over the pressure during filling, sealing, evacuation, and measurement. The cell design and sample preparation as well as the crucial sealing procedure are explained in detail. As a first proof-of-principle experiment, successful nitrogen K-edge fluorescence yield near-edge X-ray absorption fine structure experiments of a biomolecular solution are presented. For this purpose, it is shown that the careful evaluation of all involved parameters, such as window type or photon flux, is desirable for optimizing the experimental result.

  4. In vivo persistence of sister chromatid exchanges (SCE) induced by gamma rays in mouse bone marrow cells

    International Nuclear Information System (INIS)

    Morales-Ramirez, P.; Vallarino-Kelly, T.; Rodriguez-Reyes, R.

    1984-01-01

    The sister chromatid exchange (SCE) frequencies induced in bone marrow cells by in vivo irradiation with gamma rays before or after bromodeoxyuridine (BrdUrd) incorporation were compared. The frequency of SCE at different postirradiation times was also measured in bone marrow cells in vivo, irradiated before BrdUrd incorporation. Increased sensitivity to SCE induction by radiation was found in cells after BrdUrd incorporation for one cycle when compared with cells irradiated before BrdUrd incorporation. The increased SCE frequency persisted for at least 72 hr after the initial irradiation, implying that the gamma ray-induced lesion(s) capable of eliciting an SCE are persistent and cannot be easily repaired

  5. Dihydropyridines decrease X-ray-induced DNA base damage in mammalian cells

    Energy Technology Data Exchange (ETDEWEB)

    Wojewodzka, M., E-mail: marylaw@ichtj.waw.pl [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland); Gradzka, I.; Buraczewska, I.; Brzoska, K.; Sochanowicz, B. [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland); Goncharova, R.; Kuzhir, T. [Institute of Genetics and Cytology, Belarussian National Academy of Sciences, Minsk (Belarus); Szumiel, I. [Center of Radiobiology and Biological Dosimetry, Institute of Nuclear Chemistry and Technology, Warszawa (Poland)

    2009-12-01

    Compounds with the structural motif of 1,4-dihydropyridine display a broad spectrum of biological activities, often defined as bioprotective. Among them are L-type calcium channel blockers, however, also derivatives which do not block calcium channels exert various effects at the cellular and organismal levels. We examined the effect of sodium 3,5-bis-ethoxycarbonyl-2,6-dimethyl-1,4-dihydropyridine-4-carboxylate (denoted here as DHP and previously also as AV-153) on X-ray-induced DNA damage and mutation frequency at the HGPRT (hypoxanthine-guanine phosphoribosyl transferase) locus in Chinese hamster ovary CHO-K1 cells. Using formamido-pyrimidine glycosylase (FPG) comet assay, we found that 1-h DHP (10 nM) treatment before X-irradiation considerably reduced the initial level of FPG-recognized DNA base damage, which was consistent with decreased 8-oxo-7,8-dihydro-2'-deoxyguanosine content and mutation frequency lowered by about 40%. No effect on single strand break rejoining or on cell survival was observed. Similar base damage-protective effect was observed for two calcium channel blockers: nifedipine (structurally similar to DHP) or verapamil (structurally unrelated). So far, the specificity of the DHP-caused reduction in DNA damage - practically limited to base damage - has no satisfactory explanation.

  6. Investigation of X-ray-induced chromosome aberrations in 'preleukaemic' mammalian cells

    International Nuclear Information System (INIS)

    Szollar, J.

    1977-01-01

    A study was done on the frequency of numerical and structural aberrations induced by different doses of X-ray irradiation in spontaneously leukaemic AKR mice, compared with the values of healthy control CBA/H-T 6 T 6 mice. Both were irradiated under the same conditions, but their chromosomes were affected in a different way. The number of cells containing aneuploid sets, rings, fragments, or metacentric chromosomes was significantly higher in the 2-month-old AKR mice than in the control CBA group. The increased chromosomal fragility found in AKR bone marrow cells 5-7 months before the manifestation of lymphoid leukaemia might be an important factor in the development of malignant condition. This genetic imbalance could provide a possible reason for an increase of spontaneous malfunction of the cellular system, as well as for an increased sensitivity to external factors. Thus it might be connected directly with the predisposition to malignant growth, or it has an indirect role helping virus activation, or acting together with the immune deficiency, by creating a weaker system that is more sensitive to carcinogenic agents

  7. Phase-changes in cell cycle of wound tissue irradiated with 5.21 Gy soft X-rays

    International Nuclear Information System (INIS)

    Liu Jianzhong; Zhou Yuanguo; Cheng Tianmin; Zhou Ping; Liu Xia; Li Ping

    2002-01-01

    Objective: To study the phase-changes in cell cycle of wound tissue which was locally irradiated with 5.21 Gy soft X-rays. Methods: Flow cytometry and PI staining were used to analyze cell cycle. Cell proliferation was determined with BrdU labeling. Results: During 3-9 days after irradiation, the percentage of the G 0 /G 1 phase cells in wound of the control side decreased while the percentage of S phase cells increased and reached the highest value on day 9. The percentage of G 2 /M phase cells also increased, and reached its peak on day 15. The percentage of G 0 /G 1 phase cell increased in wound of the irradiation side and was higher than that of the control wound, meanwhile the percentages of S and G 2 /M cells were significantly lower than those of the control wound. In the period of 12-22 days after wounding, the percentage of S phase cells increased and reached its peak value on the 22 th day. When most of cells were in S phase and arrested dramatically. Through the whole healing process, the percentage of G 2 /M in wound of the irradiation side was lower than that of the non-irradiated wound. The BrdU-positive cells were fibroblasts, endothelial cells and smooth muscle cells. Conclusion: These results suggest that G 1 block, S phase arrest, and switch of G 2 /M with suppression of mitotic activity of these cells are induced by local 5.21 Gy soft X-ray irradiation. Therefore, wound healing delay is induced partly by cell cycle arrest

  8. Dose response of micronuclei induced by combination radiation of α-particles and γ-rays in human lymphoblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Ruiping; He, Mingyuan; Dong, Chen; Xie, Yuexia; Ye, Shuang; Yuan, Dexiao [Institute of Radiation Medicine, Fudan University, No. 2094 Xie-Tu Road, Shanghai 200032 (China); Shao, Chunlin, E-mail: clshao@shmu.edu.cn [Institute of Radiation Medicine, Fudan University, No. 2094 Xie-Tu Road, Shanghai 200032 (China)

    2013-01-15

    Highlights: ► α-Particle induced MN had a biphasic dose–response followed by a bystander model. ► MN dose–response of α- and γ-combination IR was similar to that of α-particle. ► α-Particles followed by γ-rays yielded a synergistic effect on MN induction. ► Low dose γ-rays triggered antagonistic and adaptive responses against α-particle. - Abstract: Combination radiation is a real situation of both nuclear accident exposure and space radiation environment, but its biological dosimetry is still not established. This study investigated the dose–response of micronuclei (MN) induction in lymphocyte by irradiating HMy2.CIR lymphoblast cells with α-particles, γ-rays, and their combinations. Results showed that the dose–response of MN induced by γ-rays was well-fitted with the linear-quadratic model. But for α-particle irradiation, the MN induction had a biphasic phenomenon containing a low dose hypersensitivity characteristic and its dose response could be well-stimulated with a state vector model where radiation-induced bystander effect (RIBE) was involved. For the combination exposure, the dose response of MN was similar to that of α-irradiation. However, the yield of MN was closely related to the sequence of irradiations. When the cells were irradiated with α-particles at first and then γ-rays, a synergistic effect of MN induction was observed. But when the cells were irradiated with γ-rays followed by α-particles, an antagonistic effect of MN was observed in the low dose range although this combination radiation also yielded a synergistic effect at high doses. When the interval between two irradiations was extended to 4 h, a cross-adaptive response against the other irradiation was induced by a low dose of γ-rays but not α-particles.

  9. Effect of caffeine on the expression of a major X-ray induced protein in human tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Hughes, E.N.; Boothman, D.A. (Univ. of Pennsylvania School of Medicine, Philadelphia (USA))

    1991-03-01

    We have examined the effect of caffeine on the concomitant processes of the repair of potentially lethal damage (PLD) and the synthesis of X-ray-induced proteins in the human malignant melanoma cell line, Ul-Mel. Caffeine administered at a dose of 5mM after X radiation not only inhibited PLD repair but also markedly reduced the level of XIP269, a major X-ray-induced protein whose expression has been shown to correlate with the capacity to repair PLD. The expression of the vast majority of other cellular proteins, including seven other X-ray-induced proteins, remained unchanged following caffeine treatment. A possible role for XIP269 in cell cycle delay following DNA damage by X irradiation is discussed.

  10. A diamond-anvil high-pressure cell for X-ray diffraction on a single crystal

    International Nuclear Information System (INIS)

    Malinowski, M.

    1987-01-01

    A new diamond-anvil high-pressure cell is described which can be used in single-crystal X-ray diffraction instruments to collect X-ray intensity data from single-crystal samples up to hydrostatic pressures of about 10 GPa. A unique design allows two types of diffraction geometry to be applied in single-crystal high-pressure diffraction experiments. More than 85% of the Ewald sphere is accessible, and a continuous range of 2θ values is available from 0 up to about 160 0 . Pressure may be calibrated by the ruby fluorescence technique or by the use of an internal X-ray-standard single crystal. The design of our diamond-anvil cell would allow, with little or no modification, operation at high and low temperatures, optical studies and powder diffractometer work. (orig.)

  11. Effects of X-ray irradiation on the expression of Pokemon gene in human lung adenocarcinoma cell line

    International Nuclear Information System (INIS)

    Liang Xiaofang; Zou Yue; Wang Lu; Jiang Qisheng; Li Fengsheng

    2012-01-01

    Objective: To study the dose and time effects of X-ray radiation on the expression of Pokemon gene and protein in human lung adenocarcinoma cell line A 549 . Methods: A 549 cells was exposed to different doses of X-ray (2, 4, 6 and 8 Gy), and the expression of Pokemon mRNA and protein of the cells was detected by using Quantitative real-time PCR and western-blotting at 2, 4, 8, 12, 24, and 48 h after irradiation. 3-( 4, 5-Dimethylthiazole-2-yl )-2, 5-diphenyltetrazolium bromide was used to detect the proliferation of A 549 cells at 1, 2, 3, 4, and 5 d after 2 Gy X-ray irradiation. The mock treated A 549 cells were used as the control. Results: The expression of Pokemon mRNA trended to decrease after irradiated with 4, 6 and 8 Gy in the earlier period and increased in the later period with statistical difference at the most time points (t =3.40 -154.76, P =0.000 -0.041). The expression of Pokemon protein trended to increase and reached the peak at 8 h after irradiated of 2, 4, 6 and 8 Gy with statistical difference at the most time points (t =4.18 - 89.64, P =0.000 - 0.039). Compared with the control, the proliferation of A 549 cells was significantly inhibited during 3 to 5 d after irradiation of 2 Gy (t =2.34 - 18.19, P =0.000 -0.040). Conclusions: X-ray irradiation may increase the expression of Pokemon mRNA and protein in A 549 cells, which might be correlated with radiation-resistance of A 549 cells. (authors)

  12. Effects of X-rays on CC-chemokine receptor 7 expression in human lung cancer A549 cells

    International Nuclear Information System (INIS)

    Wang Cuilan; Jiang Qisheng; Zou Yue; Li Fengsheng; Li Wei; Song Xiujun; He Rui; Wang Lu

    2011-01-01

    Objective: To study the effects of X-ray radiation on CC-chemokine receptor 7 (CCR7) expression in human non-small cell lung cancer (NSCLC) cells. Methods: Human adenocarcinoma cells of the line A549 were cultured and irradiated by X-ray at the absorbed doses of 2, 4, 6, and 8 Gy respectively by linear accelerator (with the source skin distance of 100 cm and dose rate of 442.89 cGy/min). The relative levels of CCR7 mRNA and protein expression in the A549 cells were respectively detected by real time-PCR and Western blotting 4, 12, 24, 48, and 72 h after radiation.Untreated A549 cells were used as control group. Results: The expression levels of CCR7 mRNA and protein in the A549 cells began to increase since 4 h after radiation and then decreased gradually after they reached the peak. The CCR7 mRNA expression levels 72 h after radiation of the 6 and 8 Gy groups were still significantly higher than those of the control group (t=6.75-7.26, both P<0.01), and the CCR7 protein expression levels of the 2 and 6 Gy group were still significantly higher than those of the control group (t=11.13-14.17, both P<0.01). Then the CCR7 protein expression levels of the 4 and 8 Gy groups decreased to the control group level 48 and 72 h after radiation respectively. Conclusions: The CCR7 mRNA and protein expression levels in the NSCLC cells increase after X-ray irradiation,which may be correlated with the promotion of proliferation and metastasis of NSCLC cells by X-ray irradiation at a certain dose. (authors)

  13. Effect of gamma irradiated parenchyma on the growth of irradiated potato tuber buds; Efecto del parenquina irradiado sobre el desarrollo de las yemas de tuberculos de patata tratados por radiacion GAMMA

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Gonzalez, J; Garcia Collantes, M A

    1976-07-01

    The development of buds greffed on irradiated potato parenchyma was studied. The irradiated parenchyma does not influence the sprouting capacity of buds, but it affects the way they develop. (Author) 9 refs.

  14. NADPH oxidase-mediated generation of reactive oxygen species: A new mechanism for X-ray-induced HeLa cell death

    International Nuclear Information System (INIS)

    Liu Qing; He Xiaoqing; Liu Yongsheng; Du Bingbing; Wang Xiaoyan; Zhang Weisheng; Jia Pengfei; Dong Jingmei; Ma Jianxiu; Wang Xiaohu; Li Sha; Zhang Hong

    2008-01-01

    Oxidative damage is an important mechanism in X-ray-induced cell death. Radiolysis of water molecules is a source of reactive oxygen species (ROS) that contribute to X-ray-induced cell death. In this study, we showed by ROS detection and a cell survival assay that NADPH oxidase has a very important role in X-ray-induced cell death. Under X-ray irradiation, the upregulation of the expression of NADPH oxidase membrane subunit gp91 phox was dose-dependent. Meanwhile, the cytoplasmic subunit p47 phox was translocated to the cell membrane and localized with p22 phox and gp91 phox to form reactive NADPH oxidase. Our data suggest, for the first time, that NADPH oxidase-mediated generation of ROS is an important contributor to X-ray-induced cell death. This suggests a new target for combined gene transfer and radiotherapy.

  15. High-throughput roll-to-roll X-ray characterization of polymer solar cell active layers

    DEFF Research Database (Denmark)

    Böttiger, Arvid P.L.; Jørgensen, Mikkel; Menzel, Andreas

    2012-01-01

    Synchrotron-based X-rays were used to probe active materials for polymer solar cells on flexible polyester foil. The active material was coated onto a flexible 130 micron thick polyester foil using roll-to-roll differentially pumped slot-die coating and presented variation in composition, thickness...

  16. Numerical variation of cell lysosomes of the proximal convoluted tubules of mice Kidneys submitted to different X-ray doses

    International Nuclear Information System (INIS)

    Silva Lapa, R. de C.R. da; Pacheco, I.P.; Segreto, C.

    1984-01-01

    The number of cell lysosomes of the proximal convoluted tubules of mice Kidneys (Mus musculus) before and after whole-body irradiation with different X-ray doses is confronted. The mice were sacrificed after 72 hours and the cortex fragments were conduct to electron microscopy. A statistically significant numerical reduction of the lysosomas was observed in 72 hours. (M.A.C.) [pt

  17. Methodology for in situ synchrotron X-ray studies in the laser-heated diamond anvil cell

    DEFF Research Database (Denmark)

    Mezouar, M.; Giampaoli, R.; Garbarino, G.

    2017-01-01

    A review of some important technical challenges related to in situ diamond anvil cell laser heating experimentation at synchrotron X-ray sources is presented. The problem of potential chemical reactions between the sample and the pressure medium or the carbon from the diamond anvils is illustrated...

  18. Survival of V79 cells after low doses of X-rays

    International Nuclear Information System (INIS)

    Watts, M.E.; Fowler, J.F.; Hodgkiss, R.J.; Jones, N.R.

    1984-01-01

    Doses of X-rays of the order 1-3 Gy are used in clinical multifraction regimes. Reduction in oxygen enhancement ratios (OER) and sensitizer enhancement ratios have been reported for CHO cells. The errors in determining low levels of cell kill are largely influenced by sampling and dilution errors. The authors have aimed to reduce these errors by increasing the sample size and reducing dilutions. To further assess the uncertainties involved in these experiments the data were pooled from three independent series of experiments. Asynchronous log phase Chinese hamster lung fibroblast cells have been irradiated attached to glass Petri dishes in Eagle's MEM + 10% fcs at a dose rate of 0.61 Gy min/sup -1/ under air + 5% CO/sub 2/ or nitrogen + 5% CO/sub 2/ at 18 0 C. Survival in the range 10/sup -1/ to 5 x 10/sup -3/ surviving fraction (SF) was identical at 0.61 Gy min/sup -1/ and 3.93 Gy min/sup -1/. Many previous experiments have given an OER = 3.1 at 10/sup -2/-10/sup -3/ survival. Least squares fit to the linear quadratic function log S = -(αD + βD/sup 2/) gave an OER≅3.2 at SF = 10/sup -2/. Below 6 Gy air dose (>0.2 SF) OER was reduced, but was still ≅ 2.4 at 2 Gy. The linear quadratic function gave an OER for a ≅ 1.5 (the limiting low-dose OER) and √β≅3.2

  19. Do ray cells provide a pathway for radial water movement in the stems of conifer trees?

    Science.gov (United States)

    David M. Barnard; Barbara Lachenbruch; Katherine A. McCulloh; Peter Kitin; Frederick C. Meinzer

    2013-01-01

    The pathway of radial water movement in tree stems presents an unknown with respect to whole-tree hydraulics. Radial profiles have shown substantial axial sap flow in deeper layers of sapwood (that may lack direct connection to transpiring leaves), which suggests the existence of a radial pathway for water movement. Rays in tree stems include ray tracheids and/or ray...

  20. Effects of low dose rate γ-rays on cell proliferation and survival in exponentially growing and plateau phase cultures of normal rat kidney cells

    International Nuclear Information System (INIS)

    Tsuboi, A.

    1982-01-01

    The effects of 60 Co γ-rays on cell clonogenicity and cell proliferation were examined in NRK cells in exponential and plateau growth phases during and after irradiation at various dose rates. The typical dese rate effect for the survival responses was observed between acute irradiation and continuous irradiation at dose rates of 9.6-44 rads/h. Similar dose rate effect for the perturbation of the proliferation was observed in exponentially growing cells during irradiation. Some differences were found in survival when the cells were exposed to γ-rays at 9.6 rads/h or at 13.7 rads/h. The survival curves of exponential phase cells irradiated at these dose rates showed a shape different from that observed in plateau phase cells. Namely, a steady state of survival appeared around an accumulated dose of 1000 rads (dose-rate of 9.6 rads/h) and an accumulated dose of 1500 rads (dose-rate of 13.7 rads/h) in the exponential phase cells, while such a steady state of survival was not detected in plateau phase cells after similar conditions of irradiation. Moreover, the extrapolation number of the survival curve was much larger at the lower dose rate in exponential phase cells, in contrast to a value of the unity oberved in plateau phase cells, The radiosensitivity of plateau phase cells was somewhat lower compared to exponential phase cells over the range of accumulated doses at the dose rates used. These differences in cellular responses to the radiation between the two phases could be explained by changes in cell proliferation, the redistribution of the cell cycle compartments and the repair capacity of cellular damage during irradiation. (author)

  1. Exposing primary rat retina cell cultures to γ-rays: An in vitro model for evaluating radiation responses.

    Science.gov (United States)

    Gaddini, Lucia; Balduzzi, Maria; Campa, Alessandro; Esposito, Giuseppe; Malchiodi-Albedi, Fiorella; Patrono, Clarice; Matteucci, Andrea

    2018-01-01

    Retinal tissue can receive incidental γ-rays exposure during radiotherapy either of tumors of the eye and optic nerve or of head-and-neck tumors, and during medical diagnostic procedures. Healthy retina is therefore at risk of suffering radiation-related side effects and the knowledge of pathophysiological response of retinal cells to ionizing radiations could be useful to design possible strategies of prevention and management of radiotoxicity. In this study, we have exploited an in vitro model (primary rat retinal cell culture) to study an array of biological effects induced on retinal neurons by γ-rays. Most of the different cell types present in retinal tissue - either of the neuronal or glial lineages - are preserved in primary rat retinal cultures. Similar to the retina in situ, neuronal cells undergo in vitro a maturational development shown by the formation of polarized neuritic trees and operating synapses. Since 2 Gy is the incidental dose received by the healthy retina per fraction when the standard treatment is delivered to the brain, retina cell cultures have been exposed to 1 or 2 Gy of γ-rays at different level of neuronal differentiation in vitro: days in vitro (DIV)2 or DIV8. At DIV9, retinal cultures were analyzed in terms of viability, apoptosis and characterized by immunocytochemistry to identify alterations in neuronal differentiation. After irradiation at DIV2, MTT assay revealed an evident loss of cell viability and βIII-tubulin immunostaining highlighted a marked neuritic damage, indicating that survived neurons showed an impaired differentiation. Differentiated cultures (DIV8) appeared to be more resistant with respect to undifferentiated, DIV2 cultures, both in terms of cell viability and differentiation. Apoptosis evaluated with TUNEL assay showed that irradiation at both DIV2 and DIV8 induced a significant increase in the apoptotic rate. To further investigate the effects of γ-rays on retinal neurons, we evaluated the

  2. Operando X-ray investigation of solid oxide fuel cell model electrodes

    International Nuclear Information System (INIS)

    Volkov, Sergey Aleksandrovic

    2017-04-01

    A detailed study of three solid oxide fuel cells (SOFCs) related model systems is presented in this work with the aim of the better understanding of the structural changes in cell components associated with their operation. The first model system is an La_0_._6Sr_0_._4CoO_3_-_d (LSC) on yttria-stabilized zirconia (YSZ). Changes in the YSZ(100) single crystal surface structure buried under the squared LSC microelectrode were studied at a synchrotron under operational conditions. High flux photon beam at the synchrotron allowed access to the LSC/YSZ interface. Structural information from the substrate surface at an atomic scale was acquired. Element-specific anomalous XRD data allowed to distinguish between Y and Zr scattering contributions. For the first time, it was shown that the Y cation concentration at the electrode/electrolyte interface strongly depends on the sample environment and the applied potential. The second model system is a Pt/YSZ. Buried YSZ(111) surface and dense Pt film morphology changes under operational conditions were addressed. High-energy X-rays were necessary to collect surface-sensitive information from the interface due to highly absorbing Pt film. The main conclusion is - under conditions applied, the YSZ single crystal surface remains stable at an atomic level. A nagging topic of the Pt ''phase oxide'' formation at the Pt/YSZ interface during anodic polarization was also raised. Although XRD data did not show a clear evidence of PtO_x presence at the interface, energy-dispersive X-ray analysis of the film cross-cut profile after the synchrotron experiment revealed distinct oxygen signal from delaminated parts of the film. Last but not least, the structure of a ZrO_2 ultrathin film grown on a Pt_3Zr(0001) single crystal was studied in ultra-high vacuum for the first time be means of SXRD. This model system is aiming to improve understanding of the electrolyte materials based on ZrO_2 (e.g. YSZ) at an atomic level. The results obtained

  3. Operando X-ray investigation of solid oxide fuel cell model electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, Sergey Aleksandrovic

    2017-04-15

    A detailed study of three solid oxide fuel cells (SOFCs) related model systems is presented in this work with the aim of the better understanding of the structural changes in cell components associated with their operation. The first model system is an La{sub 0.6}Sr{sub 0.4}CoO{sub 3-d} (LSC) on yttria-stabilized zirconia (YSZ). Changes in the YSZ(100) single crystal surface structure buried under the squared LSC microelectrode were studied at a synchrotron under operational conditions. High flux photon beam at the synchrotron allowed access to the LSC/YSZ interface. Structural information from the substrate surface at an atomic scale was acquired. Element-specific anomalous XRD data allowed to distinguish between Y and Zr scattering contributions. For the first time, it was shown that the Y cation concentration at the electrode/electrolyte interface strongly depends on the sample environment and the applied potential. The second model system is a Pt/YSZ. Buried YSZ(111) surface and dense Pt film morphology changes under operational conditions were addressed. High-energy X-rays were necessary to collect surface-sensitive information from the interface due to highly absorbing Pt film. The main conclusion is - under conditions applied, the YSZ single crystal surface remains stable at an atomic level. A nagging topic of the Pt ''phase oxide'' formation at the Pt/YSZ interface during anodic polarization was also raised. Although XRD data did not show a clear evidence of PtO{sub x} presence at the interface, energy-dispersive X-ray analysis of the film cross-cut profile after the synchrotron experiment revealed distinct oxygen signal from delaminated parts of the film. Last but not least, the structure of a ZrO{sub 2} ultrathin film grown on a Pt{sub 3}Zr(0001) single crystal was studied in ultra-high vacuum for the first time be means of SXRD. This model system is aiming to improve understanding of the electrolyte materials based on ZrO{sub 2} (e

  4. X-ray induced DNA double strand break production and repair in mammalian cells as measured by neutral filter elution

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, M O; Kohn, K W [National Institutes of Health, Bethesda, MD (USA)

    1979-10-01

    A neutral filter elution method was used for detecting DNA double strand breaks in mouse L1210 cells after X-ray. The assay detected the number of double strand breaks induced by as little as 1000 rad of X-ray. The rate of DNA elution through the filters under neutral conditions increased with X-ray dose. Certain conditions for deproteinization, pH, and filter type were shown to increase the assay's sensitivity. Hydrogen peroxide and Bleomycin also induced apparent DNA double strand breaks, although the ratios of double to single strand breaks varied from those produced by X-ray. The introduction of double strand cuts by HpA I restriction endonuclease in DNA lysed on filters resulted in a rapid rate of elution under neutral conditions, implying that the method can detect double strand breaks if they exist in the DNA. The eluted DNA banded with a double stranded DNA marker in cesium chloride. This evidence suggested that the assay detected DNA double strand breaks. L1210 cells were shown to rejoin most of the DNA double strand breaks induced by 5-10 krad of X-ray with a half-time of about 40 minutes. (author).

  5. Orthovoltage X-rays for Postoperative Treatment of Resected Basal Cell Carcinoma in the Head and Neck Area.

    Science.gov (United States)

    Duinkerken, Charlotte W; Lohuis, Peter J F M; Crijns, Marianne B; Navran, Arash; Haas, Rick L M; Hamming-Vrieze, Olga; Klop, W Martin C; van den Brekel, Michiel W M; Al-Mamgani, Abrahim

    Surgery is the golden standard for treating basal cell carcinomas. In case of positive tumor margins or recurrent disease, postoperative adjuvant or salvaging therapy is suggested to achieve good local control. To retrospectively report on local control and toxicity of postoperative radiotherapy by means of orthovoltage X-rays for residual or recurrent basal cell carcinoma after surgery in the head and neck area. Sixty-six surgically resected residual or recurrent basal cell carcinomas of the head and neck region were irradiated postoperatively by means of orthovoltage X-rays at the Netherlands Cancer Institute between January 2000 and February 2015. After a median follow-up duration of 30.5 months, only 5 recurrences were reported. The 5-year local control rates at 1, 3, and 5 years were 100%, 87%, and 87%, respectively. The 5-year local control rate was 92% for immediate postoperative radiotherapy of incompletely resected basal cell carcinomas, 90% for recurrences after 1 previously performed excision, and 71% for multiple recurrences, namely, a history of more than 1 excision ( P = .437). Acute toxicity healed spontaneously within 3 months. Late toxicities were mild. Radiotherapy by means of orthovoltage X-ray is an excellent alternative for re-excision in case of incompletely resected or recurrent basal cell carcinomas that are at risk of serious functional and cosmetic impairments after re-excision, with a 5-year local control rate of 87% and a low toxicity profile.

  6. Relationship between radiation dose and changes of blood cells in medical diagnostic X-ray workers in China

    International Nuclear Information System (INIS)

    Zhao Wenzheng

    1984-01-01

    The hematological changes of 2867 cases of medical X-ray workers and 1152 cases of non-X-ray medical workers were compared. It was shown that the total number of leukocytes, the numbers of neutrophils, lymphocytes and platelets were significantly lower in X-ray workers than those in controls. However, the percentages of monocytes, eosinophils, basophils and the concentration of hemoglobin were higher in the irradiated group. the difference between the two groups was statistically significant. The degree of changes in the number of blood cells was dose-dependent. A negative correlation could be found between the changes of leukocyte and neutrophil counts and cumulative dose (<250 mGy), annual dose (<15 mGy/a) and length of service of the X-ray workers; and a positive correlation existed between the percentages of basophils, eosinophils and monocytes, and the radiation dose. The abnormality rate of blood picture in the irradiated group was higher than that in the control group. Most X-ray workers with abnormal blood picture were distributed in low-dose group. The data also showed that radiation effect on male X-ray workers was greater than that on female workers. (Author)

  7. Sister chromatid exchanges induced in CHO cells by X-rays or 5.5 MeV neutrons

    International Nuclear Information System (INIS)

    Bocian, E.; Rosiek, O.; Sablinski, J.; Ziemba-Zoltowska, B.

    1986-01-01

    The induction of sister chromatid exchanges (SCEs) by X-rays (1-9 Gy) and 5.5 MeV neutrons (0.5-4 Gy) was studied in CHO cells. A dose-dependent increase of the frequency of SCE was found for both radiations when cells with BrdUrd substituted DNA were irradiated. The similar doubling dose, approx. 4 Gy, was found for X-rays and neutrons. The increase of the SCE frequency was not clearly dependent on the dose when cells with BrdUrd unsubstituted DNA were irradiated. In this case a dose of 4 Gy enhanced the SCE frequency only by the factor of 1.3. (author)

  8. Restoration of X-ray resistance and V(D)J recombination in mutant cells by Ku cDNA

    International Nuclear Information System (INIS)

    Smider, V.; Rathmell, W.K.; Chu, G.; Lieber, M.R.

    1994-01-01

    Three genetic complementation groups of rodent cells are defective for both repair of x-ray-induced double-strand breaks and V(D)J recombination. Cells from one group lack a DNA end-binding activity that is biochemically and antigenically similar to the Ku autoantigen. Transfection of complementary DNA (cDNA) that encoded the 86-kilodalton subunit of Ku rescued these mutant cells for DNA end-binding activity, x-ray resistance, and V(D)J recombination activity. These results establish a role for Ku in DNA repair and recombination. Furthermore, as a component of a DNA-dependent protein kinase, Ku may initiate a signaling pathway induced by DNA damage

  9. Sample cell for powder x-ray diffraction at up to 500 bars and 200 deg. C

    International Nuclear Information System (INIS)

    Jupe, Andrew C.; Wilkinson, Angus P.

    2006-01-01

    A low cost sample cell for powder diffraction at high pressure and temperature that employs either sapphire or steel pressure tubes is described. The cell can be assembled rapidly, facilitating the study of chemically reacting systems, and it provides good control of both pressure and temperature in a regimen where diamond anvil cells and multianvil apparatus cannot be used. The design provides a relatively large sample volume making it suitable for the study of quite large grain size materials, such as hydrating cement slurries. However, relatively high energy x rays are needed to penetrate the pressure tube

  10. ROS enhancement by silicon nanoparticles in X-ray irradiated aqueous suspensions and in glioma C6 cells

    International Nuclear Information System (INIS)

    David Gara, Pedro M.; Garabano, Natalia I.; Llansola Portoles, Manuel J.; Moreno, M. Sergio; Dodat, Diego; Casas, Oscar R.; Gonzalez, Mónica C.; Kotler, Mónica L.

    2012-01-01

    The capability of silicon nanoparticles to increase the yield of reactive species upon 4 MeV X-ray irradiation of aqueous suspensions and C6 glioma cell cultures was investigated. ROS generation was detected and quantified using several specific probes. The particles were characterized by FTIR, XPS, TEM, DLS, luminescence, and adsorption spectroscopy before and after irradiation to evaluate the effect of high energy radiation on their structure. The total concentration of O 2 •− /HO 2 • , HO • , and H 2 O 2 generated upon 4-MeV X-ray irradiation of 6.4 μM silicon nanoparticle aqueous suspensions were on the order of 10 μM per Gy, ten times higher than that obtained in similar experiments but in the absence of particles. Cytotoxic 1 O 2 was generated only in irradiation experiments containing the particles. The particle surface became oxidized to SiO 2 and the luminescence yield reduced with the irradiation dose. Changes in the surface morphology did not affect, within the experimental error, the yields of ROS generated per Gy. X-ray irradiation of glioma C6 cell cultures with incorporated silicon nanoparticles showed a marked production of ROS proportional to the radiation dose received. In the absence of nanoparticles, the cells showed no irradiation-enhanced ROS generation. The obtained results indicate that silicon nanoparticles of 1 O 2 upon X-ray irradiation opens novel approaches in the design of therapy strategies.

  11. Body-weight and chromosome aberrations induced by X-rays in somatic cells of Drosophila melanogaster

    International Nuclear Information System (INIS)

    Marco, A. de; Belloni, M.P.

    1976-01-01

    Body-weight has been shown to influence the final expression of genetic damage by X-rays in Drosophila melanogaster. If larvae of Drosophila were raised up to the third instar in media containing different amounts of the same nutrient and in different conditions of crowding a positive correlation was observed between body-weight and frequency of chromosome aberrations induced by a given dose of X-rays in the somatic cells of their nerve ganglia. This effect, present in both sexes, is most plausibly attributed to a different capacity of big and small larvae for repairing radiation damage. (orig.) [de

  12. Plant breeding by using radiation mutation - Selection of herbicide-resistant cell lines by using {gamma}-rays

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hyo Yeon [Sunchun University, Sunchun (Korea); Seo, Yong Weon [Korea University, Seoul (Korea)

    2000-04-01

    In order to develop the herbicide resistant cell lines, micro calli derived from rice anther culture and mature seed of wheat cultivars were irradiated with gamma rays. 1) The callus was dedifferentiated by 7 or 21 day pretreatment at 7 deg. C in two rice cultivars, Ilpumbyeo ad Dongjinbyeo. 2) To check the optimum concentration of herbicide, three herbicides were tested with micro calli. 3) The optimum dose of gamma ray to seeds of wheat seemed to be from 100 to 150 Gy. 4) AFLP and RAPD technique were established to develope herbicide resistant molecular marker in rice. 34 refs., 10 figs., 5 tabs. (Author)

  13. X-ray sensitive strains of CHO cells show decreased frequency of stable transfection

    International Nuclear Information System (INIS)

    Jeggo, P.; Smith, J.

    1987-01-01

    Six X-ray sensitive (xrs) strains of the Chinese hamster ovary cell line have previously been isolated and shown to have a defect in double strand break rejoining. In this study, these strains have been investigated for their ability to take up and integrate foreign DNA. All the xrs strains investigated so far have shown a decreased frequency of stable transfectants compared to their parent line, in experiments using the plasmid pSV2gpt, which contains the selectable bacterial gene, guanine phosphoribosyl transferase. This decreased frequency is observed over a wide range of DNA concentrations (0.1 to 20 μg DNA) but is more pronounced at higher DNA concentrations. In contrast, these xrs strains show the same level of transfection proficiency as the wild type parent using a transient transfection system with a plasmid containing the bacterial CAT (chloramphenicol acetyl transferase) gene. Since the level of CAT activity does not depend on integration of foreign DNA, this suggests that the xrs strains are able to take up the same amount of DNA as the parent strains, but have a defect in the integration of foreign DNA. Since this integration of foreign DNA probably occurs by non-homologous recombination, this may indicate a role of the xrs gene product in this process

  14. The effects of γ-ray ultrastructure and ethylene biosynthesis in apple pulp cells

    International Nuclear Information System (INIS)

    Xin Zhi Jiao

    1989-01-01

    Ultrastructural changes caused by gamma-ray (Co-60) irradiation were investigated in preclimacteric apple fruits during storage. Under the electron microscope, the cellulose in the cell walls was reduced to a line when treated with 40 Krad gamma radiation for 38 hr, and disappeared completely after treatment with 100 Krad. The disintegration of plasmalemma and mitochondria membranes was observed. Plasmalemma membranes were impaired after 10 Krads for 38 hr, while in the mitochondria the destruction of the original structure and its inner membrane spine began at 40 Krads for 38 hr. Moreover, the size of starch granules was reduced by the irradiation, disappearing after treatment with 100 Krads. Both ethylene production and respiration rate were drastically reduced. The reduction of ethylene production in treated apple fruit was found to be due to the decrease of ACC content and the inhibition of ethylene-forming enzyme activity. MACC content was also decreased. Fruits treated with 40 Krad gamma radiation and stored at 0-2 degrees C maintained their quality for six months

  15. Unit cell parameters of wurtzite InP nanowires determined by x-ray diffraction.

    Science.gov (United States)

    Kriegner, D; Wintersberger, E; Kawaguchi, K; Wallentin, J; Borgström, M T; Stangl, J

    2011-10-21

    High resolution x-ray diffraction is used to study the structural properties of the wurtzite polytype of InP nanowires. Wurtzite InP nanowires are grown by metal-organic vapor phase epitaxy using S-doping. From the evaluation of the Bragg peak position we determine the lattice parameters of the wurtzite InP nanowires. The unit cell dimensions are found to differ from the ones expected from geometric conversion of the cubic bulk InP lattice constant. The atomic distances along the c direction are increased whereas the atomic spacing in the a direction is reduced in comparison to the corresponding distances in the zinc-blende phase. Using core/shell nanowires with a thin core and thick nominally intrinsic shells we are able to determine the lattice parameters of wurtzite InP with a negligible influence of the S-doping due to the much larger volume in the shell. The determined material properties will enable the ab initio calculation of electronic and optical properties of wurtzite InP nanowires.

  16. Dynamic-contrast-enhanced magnetic resonance imaging of cirrhotic liver parenchyma: A comparison between gadolinium–diethylenetriamine pentaacetic acid and gadolinium–ethoxybenzyl–diethylenetriamine pentaacetic acid

    Directory of Open Access Journals (Sweden)

    Chun-Yi Lin

    2015-11-01

    Conclusion: The enhancement effect of the liver parenchyma using both MRI contrast agents was not affected by the degree of liver cirrhosis or abnormal liver function. However, it was affected by the serum-bilirubin levels in the Gd–EOB–DTPA-enhanced MRIs. Furthermore, enhancement of the liver was higher when using Gd–EOB–DTPA in the VP, DP, and HP. This knowledge is helpful when performing dynamic MRIs to diagnose focal hepatic lesions in the heterogeneous liver parenchyma.

  17. Ultrastructural and cellular damage to rat lung with x-rays: a search for target cell in lung tissue

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, I

    1975-03-01

    Radiation effects on the peripheral alveoli of conventional rats were examined by means of electron microscopy. The right hemithorax alone was exposed to various single doses of x rays. The initial cellular lesions selectively involved the cytoplasms of alveolar capillary endothelial (Ed) and type 1 epithelial (Ep 1) cells in a dose-dependent fashion, where the major alterations were multifocal vacuolations and swellings. These lesions became visible as early as 1 hr after 1000 R (the assumed mean lethal dose for Ed cells) and more. However, progenitor Ep 2 cells exhibited no obvious cytoplasmic lesions by the doses below 2000 R, indicating that Ep 2 cells are more resistant to x rays. With time following 1000 R, the capillary Ed blebbing abruptly developed in various forms from the sites presumably other than the Ed junctions. The Ed blebs and interstitial edema progressed until about 2 weeks without recovery, while some signs of cellular recovery were recognized in Ep 1 cells during this period. The observations after a long period of 6 months following 1000 R showed that the typical pulmonary fibrotic changes were initiated in the interstitium perhaps around unrepaired capillaries. Further, inflammatory reaction characterized by massive cellular infiltations was superimposed on developing pulmonary fibrosis. Considering the current knowledge about the cell sensitivity and renewal in stable tissues, the present results imply that capillary Ed cell is the primary target for the radiation lesion leading to the secondary pulmonary alterations.

  18. Effects of PTEN transfer on cell cycle progression and expression of P27kipl followed by X-ray irradiation

    International Nuclear Information System (INIS)

    Tian Mei; Wu Congmei; Liu Linlin; Piao Chunji; Li Xiuyi

    2007-01-01

    Objective: To investigate the effect of pEgr-hPTEN stable transfer combined with irradiation on the cell cycle progression and the expression of cell cycle kinase inhibitor P27 kipl protein of SHG-44 human glioma cells. Methods: pEgr-hPTEN vector containing the exogenous wild type PTEN gene was transfected into SHG-44 cells under mediation of lipofectamine in vitro, the positive cell clones were selected and amplified by using G418. Western blotting was used to measure the expression of PTEN protein. Transmission electron microscope was adopted to detect the cell ultrastructural changes and flow cytometry was adopted to analysis the changes of cell cycle progression and the expression of P27 kipl in SHG-44-sPTEN cells followed by different doses of X-ray irradiation. Results: Egr-1 promoter could be induced and activated by irradiation and then enhanced the expression of downstream PTEN gene within 5 Gy. The ultrastructure of SHG-44-sPTEN cells had many degenerative changes and many early apoptotic changes including the chromosome condensate around the nuclear envelope. pEgr-hPTEN stable transfer combined with X-ray irradiation could significantly induce G 1 arrest. The expression of P27 kipl proteins increased in SHG-44-sPTEN stable transfected cells. Conclusion: PTEN stable transfer combined with irradiation can significantly induce G 1 arrest. The molecular basis may be correlated with the enhanced expression of PTEN induced by irradiation and increased expression of cell cycle kinase inhibitor P27 kipl . (authors)

  19. The pathway of subarachnoid CSF moving into the spinal parenchyma and the role of astrocytic aquaporin-4 in this process.

    Science.gov (United States)

    Wei, Fang; Zhang, Cui; Xue, Rong; Shan, Lidong; Gong, Shan; Wang, Guoqing; Tao, Jin; Xu, Guangyin; Zhang, Guoxing; Wang, Linhui

    2017-08-01

    It has been proved that cerebrospinal fluid (CSF) in the subarachnoid space could reenter the brain parenchyma via the perivascular space. The present study was designed to explore the pathway of subarachnoid CSF flux into the spinal cord and the potential role of aquaporin-4 (AQP4) in this process. Fluorescently tagged cadaverine, for the first time, was used to study CSF movement in mice. Following intracisternal infusion of CSF tracers, the cervical spinal cord was sliced and prepared for fluorescence imaging. Some sections were subject with immunostaining in order to observe tracer distribution and AQP4 expression. Fluorescently tagged cadaverine rapidly entered the spinal cord. Tracer influx into the spinal parenchyma was time dependent. At 10min post-infusion, cadaverine was largely distributed in the superficial tissue adjacent to the pial surface. At 70min post-infusion, cadaverine was distributed in the whole cord and especially concentrated in the gray matter. Furthermore, fluorescent tracer could enter the spinal parenchyma either along the perivascular space or across the pial surface. AQP4 was observed highly expressed in the astrocytic endfeet surrounding blood vessels and the pial surface. Blocking AQP4 by its specific inhibitor TGN-020 strikingly reduced the inflow of CSF tracers into the spinal cord. Subarachnoid CSF could flow into the spinal cord along the perivascular space or across the pial surface, in which AQP4 is involved. Our observation provides a basis for the study on CSF movement in the spinal cord when some neurological diseases occur. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Electrical behavior research of silicon photo-cell used in online monitoring absorbed dose rate of γ-ray

    International Nuclear Information System (INIS)

    Yang Guixia; Li Xiaoyan; Fu Lan; Wu Wenhao; An You; Zeng Fansong

    2015-01-01

    The real-time online monitoring system for γ-ray absorbed dose rate was established to study the relationship between the photocurrent of semi-conductive silicon photo-cell BBZSGD-4 and γ-ray absorbed dose rate under the open circuit. The radioactive experiments in "6"0Co γ radiation field show that photo-cell BBZSGD-4 has good response to "6"0Co γ-ray, and their relationship accords with the linear law. The photocurrent of photo-cell can be up to 1.26 μA when the absorbed dose rate is 94.54 Gy/min. The relationship between photocurrent and the absorbed dose accords with exponential law when absorbed dose rate is 50 Gy/min, and the attenuation of photocurrent is 1% when the absorbed dose is 5445.8 Gy. Thus photo-cell BBZSGD-4 has the potential to be a real-time detector to detect low absorbed dose rate in "6"0Co γ radiation field. (authors)

  1. Comparison of two binuclear vanadium-catecholate complexes: Synthesis, X-ray structure and effects in cancer cells

    Science.gov (United States)

    Chi, Zixiang; Zhu, Linli; Lu, Xiaoming

    2011-08-01

    Two binuclear vanadium-catecholate complexes [Et 3NH] 2[V VO 2(μ-cat)] 2( 1) and [Et 3NH] 2[V VO 2(μ-N-2,3-D)] 2( 2) (cat = catechol, N-2,3-D = naphthalene-2,3-diol) have been synthesized and characterized by X-ray diffraction, IR, UV-vis spectroscopy and cyclic voltammetry (CV). X-ray analysis reveals that the structures of complexes 1 and 2 are both in the anion form of V. Et 3N works as counter-ions and connects the main frame by hydrogen bonding. The electrochemical behavior of the two complexes is studied in comparison to that of the free ligands and the two complexes display different redox potentials. Pharmaceutical screenings of complexes 1 and 2 have been made against two representative cancer cell-lines A-549 (lung cancer) and Bel-7402 (liver cancer) by MTT assay. The inhibition of cell proliferation was determined 72 h after cells were exposed to the tested compounds at a concentration of 5 μg/mL. Complex 1 exhibits well inhibition ratio against both two cell-lines (76.28% and 75.94%), while 2 displays positive and negative effect (65.36% and -68.82%) respectively. In association with X-ray and electrochemistry, a preliminary analysis about the possible inhibitory mechanism is provided.

  2. Contrast amplification of the liver parenchyma in the computer tomogram by using intravenous and peroral biliary contrast media

    International Nuclear Information System (INIS)

    Justich, E.; Sager, W.D.; Dietrich, G.; Fotter, R.; Nedden, D. zur; Innsbruck Univ.

    1980-01-01

    If intravenous, biliary contrast media are used, a slight albeit specific enhancement of contrast of the liver parenchyma occurs with the applied dosage, which can be utilised in individual cases, for example for identifying isodense lesions. Contrast amplification by the peroral cholegraphic agent under examination, is insufficient for use in computer tomography of the liver. The use of biliary contrast media usually enables very good visualisation of the extrahepatic bile ducts. Attention is drawn to the possibility of pharmakokinetic studies by means of computer tomography. (orig.) [de

  3. Cirugías Conservadoras del Parénquima Pancreático / Converving Parenchyma Pancreatic Surgeries

    Directory of Open Access Journals (Sweden)

    Giunippero Alejandro

    2015-11-01

    Full Text Available After a classical pancreatic resection the risk of endocrine and exocrine insufficiency is in the order of : 8-20 % and 20-50 % respectively 1. Conservative surgery of pancreatic parenchyma decrease the risk of insufficiency and represents the clearest benefits of this type of surgery. They are optional techniques that help the surgeon to evaluate the decision which is best for each patient and each type of lesion. Among them we will approach three of them: uncinate process resection, enucleation, median pancreatectomy.

  4. Cross-sensitivity of X-ray-hypersensitive cells derived from LEC strain rats to DNA-damaging agents

    International Nuclear Information System (INIS)

    Okui, T.; Endoh, D.; Arai, S.; Isogai, E.; Hayashi, M.

    1996-01-01

    The cross-sensitivity of X-ray-hypersensitive lung fibroblasts from LEC strain (LEC) rats to other DNA-damaging agents was examined. The LEC cells were 2- to 3-fold more sensitive to bleomycin (BLM) that induces DNA double-strand breaks, and to a cross-linking agent, mitomycin C, than the cells from WKAH strain (WKAH) rats, while they were slightly sensitive to alkylating agents, ethyl nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine, but not to UV-irradiation. Although no difference was observed in the initial yields of DNA double-strand breaks induced by BLM between LEC and WKAH cells, the repair process of DNA double-strand breaks was significantly slower in LEC cells than in WKAH cells

  5. Effect of 60Co γ-rays on growth of Agaricus blazei murill hypha and its cell shape structure

    International Nuclear Information System (INIS)

    Weng Boqi; Jiang Zhihe; Lin Yong; Huang Tingjun; Xiao Shuxia

    2003-01-01

    The effect of 60 Co γ-rays at different dosage on growth, tangle and structure of cell shape of Agarius blazei Murill (Abm) hypha were studied. The experiment results showed that the cell wall of treatment Abm hypha was thicker than that of the control, huge separation between cytoplasm and cell wall of Abm hypha appeared when Abm hypha was irradiated at the low dosage (0.2-0.5 kGy). The cell wall became thin and small separation between cytoplasm and cell wall appeared with the increase of the irradiation dosage. The growth of Abm hypha became slow and scare by irradiation with higher dosage. The growth and tangle of hypha could be improved and the yield of fruit body increased by 34.8% when irradiated with low dosage

  6. Less initial rejoining of X-ray-induced DNA double-strand breaks in cells of a small cell (U-1285) compared to a large cell (U-1810) lung carcinoma cell line

    International Nuclear Information System (INIS)

    Cedervall, B.; Sirzea, F.; Brodin, O.; Lewensohn, R.

    1994-01-01

    Cells of a small cell lung carcinoma cell line, U-1285, and an undifferentiated large cell lung carcinoma cell line, U-1810, differ in radiosensitivity in parallel to the clinical radiosensitivity of the kind of tumors from which they are derived. The surviving fraction at 2 Gy (SF2) was 0.25 that of U-1285 cells and 0.88 that of U-1810 cells. We investigated the induction of DNA double-strand breaks (DSBs) by X rays and DSB rejoining in these cell lines. To estimate the number of DSBs we used a model adapted for pulsed-field gel electrophoresis (PFGE). The induction levels were of the same magnitude. These levels of induction do not correlate with radiosensitivity as measured by cell survival assays. Rejoining of DSBs after doses in the range of 0.50 Gy was followed for 0,15,30,60 and 120 min. We found a difference in the velocity of repair during the first hour after irradiation which is parallel to the differences in radiosensitivity. Thus U-1810 cells exhibit a fast component of repair, with about half of the DSBs being rejoined during the first 15 min, whereas U-1285 cells lack such a fast component, with only about 5% of the DSBs being rejoined after the same time. In addition there was a numerical albeit not statistical difference at 120 min, with more residual DSBs in the U-1285 cells compared to the U-1810 cells. 36 refs., 5 figs

  7. Rejoining of x-ray induced chromosome breaks in human cells and its relationship to cellular repair

    International Nuclear Information System (INIS)

    Cornforth, M.N.

    1985-01-01

    A method was developed to improve the resolution for measuring breaks produced in interphase chromosomes by X-rays following the induction of premature chromosome condensation (PCC). It is based on the principle of 5-BrdU incorporation into the DNA of HeLa mitotic cells, which act as inducers of PCC when they are fused to diploid human fibroblasts. After a modified Fluorescence Plus Giemsa (FPG) protocol, the PCC stain intensely, while the mitotic inducer chromosomes stain faintly. The dose response for density inhibited (G 0 ) human cells was linear from 10.9 to 600 rad, with a slope of 0.06 breaks per cell per rad. Upon incubation at 37 0 C, half of the breaks disappeared in 2 hours. Following a dose of 600 rad the initial rate of break rejoining mirrored the rate of increase in survival from post-irradiation incubation, due to the repair of potentially lethal damage (PLD). The X-ray induced PCC rejoining characteristics from two ataxia telangiectasia (A-T) cell lines were compared to profiles obtained with normal cells. Both normal and A-T cells apparently sustained the same initial level of radiation damage, and both cell types rejoined breaks at the same rate. However, while normal cells eventually rejoined all but about 5% of the breaks produced by 600 rad, the A-T lines were left with 5-6 times the level of residual damage. These experiments demonstrate that progression of cells into S phase is not a necessary condition for the measured frequency of chromosome fragments observed in X-irradiated A-T cells

  8. Formation and Expansion of Leukemia-Specific Chromosome Aberrations in Hematopoietic Cells of X-ray Irradiated Mice

    International Nuclear Information System (INIS)

    Ban, N.; Kai, M.; Kusama, T.

    2004-01-01

    C3H/He mice develop acute myeloid leukemia (AML) after whole-body irradiation, and typical chromosome 2 deletions are found in the leukemia cells. To investigate a process of the formation and the expansion of the AML-specific deletions, we have examined its frequency in primitive hematopoietic cells that could be the target of the leukemogenesis. Male C3H/He mice were exposed to 3Gy x-rays and sacrificed after certain periods of time. Bone marrow cells were collected from the femora and a single-cell suspension from each animal was divided into two parts. One part of the cell suspension was cultured in methylcellulose medium and metaphase spreads were prepared from each growing colony. The other part was sorted to obtain Lin+ and Lin Scal cells and those cells were scored with FISH for the AML-specific deletions. Karyotyping of the cultured cells detected signs of the delayed chromosomal instability, but an aberration involving chromosome 2 has not been found so far. FISH to the sorted cells, however, revealed the ANL-specific deletions could be produced in the primitive hematopoietic cells as an early event of radiation exposure. (Author) 16 refs

  9. Mutagenic adaptive response to high-LET radiation in human lymphoblastoid cells exposed to X-rays.

    Science.gov (United States)

    Varès, Guillaume; Wang, Bing; Tanaka, Kaoru; Kakimoto, Ayana; Eguchi-Kasai, Kyomi; Nenoi, Mitsuru

    2011-01-10

    The ability of cells to adapt low-dose or low-dose rate radiation is well known. High-LET radiation has unique characteristics, and the data concerning low doses effects and high-LET radiation remain fragmented. In this study, we assessed in vitro the ability of low doses of X-rays to induce an adaptive response (AR) to a subsequent challenging dose of heavy-ion radiation. Lymphoblastoid cells (TK6, AHH-1, NH32) were exposed to priming 0.02-0.1Gy X-rays, followed 6h later by challenging 1Gy heavy-ion radiation (carbon-ion: 20 and 40keV/μm, neon-ion: 150keV/μm). Pre-exposure of p53-competent cells resulted in decreased mutation frequencies at hypoxanthine-guanine phosphoribosyl transferase locus and different H2AX phosphorylation kinetics, as compared to cells exposed to challenging radiation alone. This phenomenon did not seem to be linked with cell cycle effects or radiation-induced apoptosis. Taken together, our results suggested the existence of an AR to mutagenic effects of heavy-ion radiation in lymphoblastoid cells and the involvement of double-strand break repair mechanisms. Copyright © 2010 Elsevier B.V. All rights reserved.

  10. Identification of 5'-adenylylimidodiphosphate-hydrolyzing enzyme activity in rabbit taste bud cells using X-ray microanalysis

    International Nuclear Information System (INIS)

    Asanuma, N.

    1990-01-01

    X-ray microanalysis has been used to characterize the enzyme activity hydrolyzing the ATP analogue 5'-adenylylimidodiphosphate (AMP-PNP) in taste bud cells. Rabbit foliate papillae fixed with paraformaldehyde and glutaraldehyde were incubated cytochemically with AMP-PNP as the substrate and lead ion as capture agent. The reaction product which appeared on the microvilli of taste bud cells was examined using an energy dispersive X-ray microanalyzer connected to an analytical electron microscope. The X-ray spectrum thus obtained was compared with that obtained from the product obtained from the demonstration of ATPase activity. Comparison of the phosphorus/lead ratios in the two products showed that twice as much phosphorus was released from an AMP-PNP molecule by the activity in question compared with that released from an ATP molecule by ATPase activity. This indicates that the enzyme hydrolyzes AMP-PNP into AMP and imidodiphosphate and that the enzyme is adenylate cyclase or ATP pyrophosphohydrolase, which possesses a similar hydrolytic property, but not ATPase or alkaline phosphatase, which hydrolyzes AMP-PNP into ADP-NH2 and orthophosphate. This paper provides an example of the use of X-ray microanalysis as a tool for enzyme distinction. The method is applicable to a variety of enzymes and tissues

  11. Targeting transferrin receptors at the blood-brain barrier improves the uptake of immunoliposomes and subsequent cargo transport into the brain parenchyma.

    Science.gov (United States)

    Johnsen, Kasper Bendix; Burkhart, Annette; Melander, Fredrik; Kempen, Paul Joseph; Vejlebo, Jonas Bruun; Siupka, Piotr; Nielsen, Morten Schallburg; Andresen, Thomas Lars; Moos, Torben

    2017-09-04

    Drug delivery to the brain is hampered by the presence of the blood-brain barrier, which excludes most molecules from freely diffusing into the brain, and tightly regulates the active transport mechanisms that ensure sufficient delivery of nutrients to the brain parenchyma. Harnessing the possibility of delivering neuroactive drugs by way of receptors already present on the brain endothelium has been of interest for many years. The transferrin receptor is of special interest since its expression is limited to the endothelium of the brain as opposed to peripheral endothelium. Here, we investigate the possibility of delivering immunoliposomes and their encapsulated cargo to the brain via targeting of the transferrin receptor. We find that transferrin receptor-targeting increases the association between the immunoliposomes and primary endothelial cells in vitro, but that this does not correlate with increased cargo transcytosis. Furthermore, we show that the transferrin receptor-targeted immunoliposomes accumulate along the microvessels of the brains of rats, but find no evidence for transcytosis of the immunoliposome. Conversely, the increased accumulation correlated both with increased cargo uptake in the brain endothelium and subsequent cargo transport into the brain. These findings suggest that transferrin receptor-targeting is a relevant strategy of increasing drug exposure to the brain.

  12. Site-targeted non-viral gene delivery by direct DNA injection into the pancreatic parenchyma and subsequent in vivo electroporation in mice.

    Science.gov (United States)

    Sato, Masahiro; Inada, Emi; Saitoh, Issei; Ohtsuka, Masato; Nakamura, Shingo; Sakurai, Takayuki; Watanabe, Satoshi

    2013-11-01

    The pancreas is considered an important gene therapy target because the organ is the site of several high burden diseases, including diabetes mellitus, cystic fibrosis, and pancreatic cancer. We aimed to develop an efficient in vivo gene delivery system using non-viral DNA. Direct intra-parenchymal injection of a solution containing circular plasmid pmaxGFP DNA was performed on adult anesthetized ICR female mice. The injection site was sandwiched with a pair of tweezer-type electrode disks, and electroporated using a square-pulse generator. Green fluorescent protein (GFP) expression within the injected pancreatic portion was observed one day after gene delivery. GFP expression reduced to baseline within a week of transfection. Application of voltages over 40 V resulted in tissue damage during electroporation. We demonstrate that electroporation is effective for safe and efficient transfection of pancreatic cells. This novel gene delivery method to the pancreatic parenchyma may find application in gene therapy strategies for pancreatic diseases and in investigation of specific gene function in situ. © 2013 The Authors. Biotechnology Journal published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptions are made.

  13. Dose Distribution Calculation Using MCNPX Code in the Gamma-ray Irradiation Cell

    International Nuclear Information System (INIS)

    Kim, Yong Ho

    1991-02-01

    60 Co-gamma irradiators have long been used for foods sterilization, plant mutation and development of radio-protective agents, radio-sensitizers and other purposes. The Applied Radiological Science Research Institute of Cheju National University has a multipurpose gamma irradiation facility loaded with a MDS Nordin standard 60 Co source (C188), of which the initial activity was 400 TBq (10,800 Ci) on February 19, 2004. This panoramic gamma irradiator is designed to irradiate in all directions various samples such as plants, cultured cells and mice to administer given radiation doses. In order to give accurate doses to irradiation samples, appropriate methods of evaluating, both by calculation and measurement, the radiation doses delivered to the samples should be set up. Computational models have been developed to evaluate the radiation dose distributions inside the irradiation chamber and the radiation doses delivered to typical biolological samples which are frequently irradiated in the facility. The computational models are based on using the MCNPX code. The horizontal and vertical dose distributions has been calculated inside the irradiation chamber and compared the calculated results with measured data obtained with radiation dosimeters to verify the computational models. The radiation dosimeters employed are a Famer's type ion chamber and MOSFET dosimeters. Radiation doses were calculated by computational models, which were delivered to cultured cell samples contained in test tubes and to a mouse fixed in a irradiation cage, and compared the calculated results with the measured data. The computation models are also tested to see if they can accurately simulate the case where a thick lead shield is placed between the source and detector. Three tally options of the MCNPX code, F4, F5 and F6, are alternately used to see which option produces optimum results. The computation models are also used to calculate gamma ray energy spectra of a BGO scintillator at

  14. Unit cell determination of epitaxial thin films based on reciprocal space vectors by high-resolution X-ray diffractometry

    OpenAIRE

    Yang, Ping; Liu, Huajun; Chen, Zuhuang; Chen, Lang; Wang, John

    2013-01-01

    A new approach, based on reciprocal space vectors (RSVs), is developed to determine Bravais lattice types and accurate lattice parameters of epitaxial thin films by high-resolution X-ray diffractometry (HR-XRD). The lattice parameters of single crystal substrates are employed as references to correct the systematic experimental errors of RSVs of thin films. The general procedure is summarized, involving correction of RSVs, derivation of raw unit cell, subsequent conversion to the Niggli unit ...

  15. The studies of effects of 60Co γ-rays on DNA damage and repair in tumor cells

    International Nuclear Information System (INIS)

    Su Liaoyuan; Huang Hanxian; Cen Jiannong

    1997-06-01

    The effects of 60 Co γ-rays and its combination with hyperthermia on DNA strand breaks and their repair in L 5178y cells were studied using alkaline elution technique. When the cells were heated at 43 degree C for 30 min, there was obvious inhibition of repair of DNA damage caused by γ-irradiation. The hyperthermia before irradiation produced better inhibiting effect than that after irradiation. The effects of radiation on DNA strand breaks and its repair in HL-60 cells and HL-60 (VCR) cells were analyzed using technique of hydroxyapatite chromatography and the results sowed that the extent of DNA strand breaks in HL-60 cells and HL-60 (VCR) cells induced by irradiation was not markedly different, but the power of repair of strand breaks and the radioresistance of function of DNA synthesis in HL-60 (VCR) cells were higher than those in HL-60 cells. The difference was obvious. The results suggest that the heterogeneity of radiosensitivity of leukemia cells is correlated with its drug resistance. (10 refs., 3 tabs.)

  16. Isolation and partial characterisation of a mammalian cell mutant hypersensitive to topoisomerase II inhibitors and X-rays

    International Nuclear Information System (INIS)

    Davies, S.M.; Davies, S.L.; Hickson, I.D.; Hall, A.G.

    1990-01-01

    The authors have isolated, following one-step mutagenesis, a Chinese hamster ovary cell mutant hypersensitive to the intercalating agent, adriamycin. This agent exerts at least part of its cytotoxic action via inhibition of the nuclear enzyme, topoisomerase II. The mutant, designated ADR-3, showed hypersensitivity to all classes of topoisomerase II inhibitors, inlcuding actinomycin D, amsacrine (m-AMSA), etoposide (VP16) and mitoxantrone. ADR-3 cells also showed cross-sensitivity to ionizing radiation, but not no UV light. Topoisomerase II activity was elevated to a small but significant degree in ADR-3 cells, and this was reflected in a 1.5-fold higher level of topoisomerase II protein in ADR-3 than in CHO-K1 cells, as judged by Western blotting. ADR-3 cells were hypersensitive to cumene hydroperoxide but cross-resistant to hydrogen peroxide, suggesting possible abnormality in the detoxification of peroxides by glutathione peroxidase or catalase. Glutathione peroxidase activity against hydroperoxide was elevated to a small but significant extent in mutant cells. Catalase levels were not significantly different in ADR-3 and CHO-K1 cells. ADR-3 cells were recessive in hybrids with parental CHO-K1 cells with respect to sensitivity to topoisomerase II inhibitors and X-rays, and represent a different genetic complementation group from the previously reported adriamycin-sensitive mutant, ADR-1. (author). 34 refs.; 5 figs.; 3 tabs

  17. Evaluating the effect of a wavelet enhancement method in characterization of simulated lesions embedded in dense breast parenchyma

    International Nuclear Information System (INIS)

    Costaridou, L.; Skiadopoulos, S.; Sakellaropoulos, P.; Panayiotakis, G.; Likaki, E.; Kalogeropoulou, C.P.

    2005-01-01

    Presence of dense parenchyma in mammographic images masks lesions resulting in either missed detections or mischaracterizations, thus decreasing mammographic sensitivity and specificity. The aim of this study is evaluating the effect of a wavelet enhancement method on dense parenchyma for a lesion contour characterization task, using simulated lesions. The method is recently introduced, based on a two-stage process, locally adaptive denoising by soft-thresholding and enhancement by linear stretching. Sixty simulated low-contrast lesions of known image characteristics were generated and embedded in dense breast areas of normal mammographic images selected from the DDSM database. Evaluation was carried out by an observer performance comparative study between the processed and initial images. The task for four radiologists was to classify each simulated lesion with respect to contour sharpness/unsharpness. ROC analysis was performed. Combining radiologists' responses, values of the area under ROC curve (A z ) were 0.93 (95% CI 0.89, 0.96) and 0.81 (CI 0.75, 0.86) for processed and initial images, respectively. This difference in A z values was statistically significant (Student's t-test, P<0.05), indicating the effectiveness of the enhancement method. The specific wavelet enhancement method should be tested for lesion contour characterization tasks in softcopy-based mammographic display environment using naturally occurring pathological lesions and normal cases. (orig.)

  18. Evaluating the effect of a wavelet enhancement method in characterization of simulated lesions embedded in dense breast parenchyma

    Energy Technology Data Exchange (ETDEWEB)

    Costaridou, L.; Skiadopoulos, S.; Sakellaropoulos, P.; Panayiotakis, G. [University of Patras, Department of Medical Physics, Patras (Greece); Likaki, E.; Kalogeropoulou, C.P. [University of Patras, Department of Radiology, Patras (Greece)

    2005-08-01

    Presence of dense parenchyma in mammographic images masks lesions resulting in either missed detections or mischaracterizations, thus decreasing mammographic sensitivity and specificity. The aim of this study is evaluating the effect of a wavelet enhancement method on dense parenchyma for a lesion contour characterization task, using simulated lesions. The method is recently introduced, based on a two-stage process, locally adaptive denoising by soft-thresholding and enhancement by linear stretching. Sixty simulated low-contrast lesions of known image characteristics were generated and embedded in dense breast areas of normal mammographic images selected from the DDSM database. Evaluation was carried out by an observer performance comparative study between the processed and initial images. The task for four radiologists was to classify each simulated lesion with respect to contour sharpness/unsharpness. ROC analysis was performed. Combining radiologists' responses, values of the area under ROC curve (A{sub z}) were 0.93 (95% CI 0.89, 0.96) and 0.81 (CI 0.75, 0.86) for processed and initial images, respectively. This difference in A{sub z} values was statistically significant (Student's t-test, P<0.05), indicating the effectiveness of the enhancement method. The specific wavelet enhancement method should be tested for lesion contour characterization tasks in softcopy-based mammographic display environment using naturally occurring pathological lesions and normal cases. (orig.)

  19. Different gene expression of Normal lymphobloastoid cells which exposure to different dose of 60Co γ-ray

    International Nuclear Information System (INIS)

    Xiao Yao; Yang Jian; Gao Xian; Qin Yanghua; Sun Ding; Hai Ling

    2008-01-01

    Objective: To study on the gene expression of normal lymphoblastoid cells(AHH-1) which exposure to difference dose of 60 Co γ-ray, analyses the essential different biological effect.. Methods Human AHH-1 normal line was irradiated by 60 Co γ-rays. Used human cDNA microarray to develop the transcriptional levels of the genes by hybridizing the mRNA of cells 8 h after exposured in different dose and the control cells. Cluster analysis, discrimination and bolting were used to filter the effective genes of differential expression. Results The results of data analysis showed 23 genes of differential expression closely related to biological effect of 2.0 Gy radiation, 5 genes express changed only by 0.5 Gy radiation, 5 genes express apparently both in 2.0 Gy and 0.5 Gy radiation. Conclusion: The different dose γ-rays radiation-induced significant changes in gene expression, such as PAPLN, TP53INP1, PTENP1, FOS and TPR seem to be some important components of cellular radioresponse. (authors)

  20. Enhanced micronucleus formation in the descendants of {gamma}-ray-irradiated tobacco cells: Evidence for radiation-induced genomic instability in plant cells

    Energy Technology Data Exchange (ETDEWEB)

    Yokota, Yuichiro, E-mail: yokota.yuichiro@jaea.go.jp [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Funayama, Tomoo; Hase, Yoshihiro [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan); Hamada, Nobuyuki [Radiation Safety Research Center, Nuclear Technology Research Laboratory, Central Research Institute of Electric Power Industry, 2-11-1 Iwado-kita, Komae, Tokyo 201-8511 (Japan); Kobayashi, Yasuhiko; Tanaka, Atsushi; Narumi, Issay [Life Science and Biotechnology Division, Quantum Beam Science Directorate, Japan Atomic Energy Agency, 1233 Watanuki-machi, Takasaki, Gunma 370-1292 (Japan)

    2010-09-10

    Ionizing radiation-induced genomic instability has been documented in various end points such as chromosomal aberrations and mutations, which arises in the descendants of irradiated mammalian or yeast cells many generations after the initial insult. This study aimed at addressing radiation-induced genomic instability in higher plant tobacco cells. We thus investigated micronucleus (MN) formation and cell proliferation in tobacco cells irradiated with {gamma}-rays and their descendants. In {gamma}-irradiated cells, cell cycle was arrested at G{sub 2}/M phase at around 24 h post-irradiation but released afterward. In contrast, MN frequency peaked at 48 h post-irradiation. Almost half of 40 Gy-irradiated cells had MN at 48 h post-irradiation, but proliferated as actively as sham-irradiated cells up to 120 h post-irradiation. Moreover, the descendants that have undergone at least 22 generations after irradiation still showed a two-fold MN frequency compared to sham-irradiated cells. This is the direct evidence for radiation-induced genomic instability in tobacco cells.

  1. Effect of an acute exposure of rat testes to gamma rays on germ cells and on Sertoli and Leydig cell functions

    International Nuclear Information System (INIS)

    Pinon-Lataillade, G.; Maas, J.; Viguier-Martinez, M.C.; Touzalin, A.M.; Jegou, B.

    1991-01-01

    Germ cells and Sertoli and Leydig cell functions were studied from 7 to 180 days after an acute exposure of 2-month-old rat testes to 9 Gy of γ rays. Body weight, testis and epididymal weights were recorded. Sertoli cell parameters (androgen-binding protein, ABP, in caput epididymis and plasma follicle stimulating hormone, FSH) and Leydig cell parameters (plasma luteinizing hormone, LH, testosterone and prostate and seminal vesicle weights) were determined together with the number of germ cells and Sertoli cells. Irradiation did not affect body weight but significantly reduced testicular and epididymal weights from day 7 and day 15 post-irradiation respectively. The cells killed by irradiation were mainly spermatogonia and preleptotene spermatocytes engaged in replicating their DNA at the time of exposure, but all spermatocytes seemed damaged as they gave abnormal descendent cells. By day 34, only elongated spermatids remained in a few tubules and thereafter very little regeneration of the seminiferous epithelium occurred, except for one rat which showed a better regeneration. Levels of ABP decreased by day 15 when the germ cell depletion had reached the pachytene spermatocytes, whereas FSH and LH levels rose when the number of elongated spermatids decreased. Levels of testosterone and the weight of the seminal vesicles did not change; occasionally, the prostate weight was slightly reduced. These results support our hypothesis that pachytene spermatocytes and elongated spermatids are involved in influencing some aspects of Sertoli cell function in the adult rat

  2. Effect of taurine on expressions of MMP-2 in K562 leukemia cell line exposed to γ-rays

    International Nuclear Information System (INIS)

    Fan Yan; Wu Shiliang; Xu Lan; Chou Hao; Zhou Yinghui

    2003-01-01

    Objective: To study the effect of γ-irradiation on expressions of MMP-2 in leukaemia cells and the suppressive effect of taurine(Tau) on irradiated tumour cells in terms of cellular level. Methods: The cells in the control group and Tau (50 mg/L, 100 mg/L, 200 mg/L) groups were irradiated with 15 Gy γ-rays. The expressions of MMP-2 were examined through Western-blotting after handled with gel-loading buffer within 12 h. Results: The expressions of MMP-2 were enhanced evidently in the positive control group, while they were less in the negative control group. In the Tau(50 mg/L, 100 mg/L, 200 mg/L) groups, the expressions of MMP-2 were diminished in turns, and they were almost identical between the negative control group and the Tau 200 mg/L group. Conclusion: Irradiation with γ-rays at a dose of 15 Gy can significantly stimulate the expressions of MMP-2 in K562 cells; Tau can inhibit the expressions of MMP-2 and its effect depends on to its dosage; Tau can inhabit the invasiveness and migration of irradiated tumour cells, so it has the biologic protective and therapeutic effects

  3. Distribution of elements in rat peripheral axons and nerve cell bodies determined by x-ray microprobe analysis

    Energy Technology Data Exchange (ETDEWEB)

    LoPachin, R.M. Jr.; Lowery, J.; Eichberg, J.; Kirkpatrick, J.B.; Cartwright, J. Jr.; Saubermann, A.J.

    1988-09-01

    X-ray microprobe analysis was used to determine concentrations (millimoles of element per kilogram dry weight) of Na, P, Cl, K, and Ca in cellular compartments of frozen, unfixed sections of rat sciatic and tibial nerves and dorsal root ganglion (DRG). Five compartments were examined in peripheral nerve (axoplasm, mitochondria, myelin, extraaxonal space, and Schwann cell cytoplasm), and four were analyzed in DRG nerve cell bodies (cytoplasm, mitochondria, nucleus, and nucleolus). Each morphological compartment exhibited characteristic concentrations of elements. The extraaxonal space contained high concentrations of Na, Cl, and Ca, whereas intraaxonal compartments exhibited lower concentrations of these elements but relatively high K contents. Nerve axoplasm and axonal mitochondria had similar elemental profiles, and both compartments displayed proximodistal gradients of decreasing levels of K, Cl, and, to some extent, Na. Myelin had a selectively high P concentration with low levels of other elements. The elemental concentrations of Schwann cell cytoplasm and DRG were similar, but both were different from that of axoplasm, in that K and Cl were markedly lower whereas P was higher. DRG cell nuclei contained substantially higher K levels than cytoplasm. The subcellular distribution of elements was clearly shown by color-coded images generated by computer-directed digital x-ray imaging. The results of this study demonstrate characteristic elemental distributions for each anatomical compartment, which doubtless reflect nerve cell structure and function.

  4. Low Doses of Gamma Rays Reduce the Sensitivity of Cervical Carcinoma Cells to Subsequent Treatment with Cisplatin

    International Nuclear Information System (INIS)

    Osmak, M.; Brozovic, A.

    2003-01-01

    One of the major challenges of modern genetics is to apply recent advances in mutation research to improve the accuracy of the estimates of the genetic risk for humans. Because of the important implications for radiation protection, biological effects of low-dose radiation have been a focus of research in recent years. Previously we have found that human cervical carcinoma HeLa cells irradiated repeatedly with low doses of gamma rays (HeLa1500 cells) became resistant to cisplatin. In this study we examine whether this effect was caused by inhibition of apoptosis. In HeLa and HeLa1500 cells we determined the induction of apoptosis following the treatment with cisplatin (i) by counting apoptotic cells with characteristic morphological changes, (ii) by analysing the expression of apoptotic genes involved in cytochrome c/Apaf-1/caspase-9 and in Fas/FasL pathways by Western blot method, and (iii) by estimating the activities of caspases by commercial caspase detection kits. Our results show that low doses of gamma rays induced alterations in human cervical carcinoma cells that were reflected in inhibition of p53-independent cisplatin-induced apoptosis due to reduced activity of caspase 3. (author)

  5. X-ray irradiation induced reversible resistance change in Pt/TiO2/Pt cells.

    Science.gov (United States)

    Chang, Seo Hyoung; Kim, Jungho; Phatak, Charudatta; D'Aquila, Kenneth; Kim, Seong Keun; Kim, Jiyoon; Song, Seul Ji; Hwang, Cheol Seong; Eastman, Jeffrey A; Freeland, John W; Hong, Seungbum

    2014-02-25

    The interaction between X-rays and matter is an intriguing topic for both fundamental science and possible applications. In particular, synchrotron-based brilliant X-ray beams have been used as a powerful diagnostic tool to unveil nanoscale phenomena in functional materials. However, it has not been widely investigated how functional materials respond to the brilliant X-rays. Here, we report the X-ray-induced reversible resistance change in 40-nm-thick TiO2 films sandwiched by Pt top and bottom electrodes, and propose the physical mechanism behind the emergent phenomenon. Our findings indicate that there exists a photovoltaic-like effect, which modulates the resistance reversibly by a few orders of magnitude, depending on the intensity of impinging X-rays. We found that this effect, combined with the X-ray irradiation induced phase transition confirmed by transmission electron microscopy, triggers a nonvolatile reversible resistance change. Understanding X-ray-controlled reversible resistance changes can provide possibilities to control initial resistance states of functional materials, which could be useful for future information and energy storage devices.

  6. Gene mutations, chromosome aberrations and survival after X-ray irradiation of cultured Chinese hamster cells at cysteamine protection

    International Nuclear Information System (INIS)

    Elisova, I.V.; Feoktistova, I.P.

    1983-01-01

    The culture of Chinese hamster cells (clone 431) has been used to study cysteamine action on mutagenous effect of X-rays, determined by the induction of resistance of gene mutations to 6-thioguanine and chromosomal abberations, as well as on the reproductive form of death of irradiated cells. Dose--- effect curves are obtained under conditions of irradiation with and without protector. The factor of dose alteration is 2.0 for chromosomal aberrations and cell survival, and 2.8 for gene mutations. It is sUpposed that cysteamine affects the general mechanisms, which take part in the realis zation of injuries that bring about gene mutations, chromosomal aberrations and cell lethality

  7. R.b.e. of 50 kVp X-rays and 660 keV γ-rays (137Cs) with respect to the production of DNA damage, repair and cell-killing in Escherichia coli K-12

    International Nuclear Information System (INIS)

    Bonura, T.; Youngs, D.A.; Smith, K.C.

    1975-01-01

    A comparison has been made of the efficiency of cell-killing, DNA single-strand breakage and double-strand breakage in an Escherichia coli K-12 wild-type strain after irradiation with soft X-rays (50 kVp) and hard γ-rays (660 keV) under aerobic conditions. Irradiation with 50 kVp X-rays resulted in 1.47 times more cell-killing than was observed with 137 Cs γ-rays based on a comparison of D 0 values evaluated from the survival curves. DNA sedimentation studies showed that, although 50 kVp X-rays were 1.93 times more effective than 137 Cs γ-rays in producing DNA double-strand breaks, there was no significant difference between the two qualities of radiation with respect to the initial number of single-strand breaks produced. When the cells were irradiated and allowed to repair maximally in minimal medium, 1.57 times more unrepaired DNA single-strand breaks remained per krad after irradiation with 50 kVp X-rays than with 137 Cs γ-rays. The increased yield of DNA double-strand breaks resulting from 50 kVp X-irradiation may account for most of these additional unrepaired single-strand breaks, since single- and double-strand breaks are indistinguishable on alkaline sucrose gradients. These results suggest that the greater r.b.e. of 50 kVp X-rays may be related to an increased effectiveness for producing DNA double-strand breaks compared with the higher energy 137 Cs γ-rays. (author)

  8. Studies on the effects of adriamycin-derivatives in combination with X-rays on MeWo- and Be11-cells

    International Nuclear Information System (INIS)

    Krueger, M.; Beuningen, D. van; Streffer, C.

    1990-01-01

    The survival rate of human melanoma cells after X-ray irradiation, treamtment with adriamycin derivatives and combined treatment with X-rays and adriamycin derivatives was measured by means of the colony formation test. After X-ray irradiation the melanoma cells showed a high resistance for cell survival. In all tests the Be11-cells were more resistant than MeWo-cells. On combined exposure especially with higher doses of adriamycin derivatives, both cell lines showed the interesting effect, that with increasing concentration the survival rate decreased whereas the D 0 increased. Aclacinomycin-A (ACM-A) and Pirarubicin reduced recovery processes after X-ray irradiation. Therefore Be11-cells showed a four times higher DMF (dosis modifying factor) after ACM-A-treatment than MeWo-cells. Low ACM-A-concentrations combined with low X-ray doses showed on both cell lines supraadditive effects. The effect of pirarubicin was in most of the tests only additive. Compared with ACM-A, pirarubicin was less cytotoxic, showed a larger therapeutic range, caused a smaller D 0 and D q and had a supraadditive effect in low concentrations on both cell lines. For clinical combined therapy with patients ACM-A is probably better suited than pirarubicin. (orig.) [de

  9. Response of human lymphoblastoid cells to HZE (iron ions) or gamma-rays

    Data.gov (United States)

    National Aeronautics and Space Administration — Transcriptional profiling of human lymphoblastoid TK6 cells comparing mock irradiated cells with cells exposed 24 hours previously to 1.67 Gy HZE (1 GeV/amu iron...

  10. Circulating blocking factors of lymphoid-cell cytotoxicity in x-ray-induced rat small-bowel adenocarcinoma

    International Nuclear Information System (INIS)

    Stevens, R.H.; Brooks, G.P.; Osborne, J.W.

    1979-01-01

    Circulating blocking factors capable of abrogating cell-mediated immune responses measured by in vitro lymphoid-cell cytotoxicity were identified in the sera of Holtzman outbred rats 6 to 9 months after a single exposure of only the temporarily exteriorized, hypoxic ileum and jejunum to 1700 to 2000 R of X radiation. Such factors were found to exist in the serum of every animal exposed to the ionizing radiation regardless of whether a visibly identifiable small-bowel adenocarcinoma existed or subsequently would develop. Protection of cultured x-ray-induced rat small-bowel cancer cells from destruction by tumor-sensitized lymphoid cells as measured by the release of lactoperoxidase-catalyzed radioiodinated membrane proteins from the tumor target cells was conferred by the action of the blocking factors at both effector and target cell levels. The results of this study demonstrate that exposure of only the rat small intestine to ionizing radiation leads to elaboration of circulating factors identifiable several months postirradiation which will block cell-mediated immune responses directed against cancer cells developing in the exposed tissue

  11. Microscopic and flow cytometric study of micronuclei in iododeoxyuridine labelled cells irradiated with soft X-rays

    International Nuclear Information System (INIS)

    Ludwikow, G.; Staalnacke, C.G.; Johanson, K.J.; Sundell-Bergman, S.; Richter, S.; Swedish Univ. of Agricultural Sciences, Uppsala; Uppsala Univ.

    1990-01-01

    Iododeoxyuridine labelled (IUdR(+)) and unlabelled (IUdR(-)) CHO cells irradiated with 2 Gy of soft X-rays showed only minor differences in the kinetics of micronuclei formation during the first 20 hours postirradiation period. Between 20 to 40 hours, the IUdR(-) cells showed approximately a constant number of micronuclei while the number of micronuclei in IUdR(+) cells was still increasing. The frequency of micronuclei was higher in IUdR(+) cells compared to IUdR(-) cells at 24 hours after irradiation with various doses up to 4.0 Gy. Dose modifying factors were found to be 1.3 (microscopic evaluation) and 1.8 (flow cytometric evaluation). Flow cytometry with use of two parameters, fluorescence from propidium iodide and light scattering, seems to be a good tool to estimate the frequency of micronuclei in CHO cells in the dose range up to about 4 Gy. At higher doses perturbation of the cell cycle and the appearance of dying cells will influence the results. (orig.)

  12. Medium from X-rayed cultures induces DNA strand-breaks in non-irradiated HeLa cells

    International Nuclear Information System (INIS)

    Ikushima, T.; Okuyama, K.; Tanizaki, Y.

    2002-01-01

    There is growing evidence to indicate that several types of responses are induced by ionizing radiation in non-irradiated cells. Such bystander effects include the killing of non-irradiated cells, the induction of sister chromatid exchanges and chromosomal aberrations, and the induction of gene mutations and chromosomal instability and enhanced cell growth. In the present study, we assessed whether the medium from irradiated cultures can induce DNA strand-breaks in non-irradiated cells, using single-cell gel electrophoresis assay (comet assay). HeLa cells in culture were irradiated with 0.5 to 8 Gy of 140 kVp X-rays and one hour later, the medium was taken from the irradiated culture, passed through a filter and transferred to the parallel culture of non-irradiated HeLa cells as non-target cells. After incubation for 30 min, the comet assay was performed under alkaline and neutral conditions. Such treatments resulted in a dose-dependent increase in tail moment under either alkaline or neutral condition, indicating the induction of DNA single- or double-strand breaks, respectively. It was also shown that the clonogenic survival was reduced in the cells cultured in the medium from irradiated cultures. Such a change was not detected at all when medium alone was irradiated. These results provided disputed evidence that irradiated cells released certain genotoxic factor(s) into the culture medium that can induce DNA strand breaks leading to cell death. Our results suggest that physical contact between irradiated and non-irradiated cells may not be necessary for the bystander effects observed in this study. It appears that bystander responses may be mediated by multiple mechanisms

  13. ROS enhancement by silicon nanoparticles in X-ray irradiated aqueous suspensions and in glioma C6 cells

    Energy Technology Data Exchange (ETDEWEB)

    David Gara, Pedro M. [CITOMA, Fundacion Avanzar, Instituto de Terapia Radiante S.A., CIO La Plata (Argentina); Garabano, Natalia I. [University of Buenos Aires, Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, UBA (Argentina); Llansola Portoles, Manuel J. [UNLP, INIFTA, Departamento de Quimica, Facultad de Ciencias Exactas (Argentina); Moreno, M. Sergio [Centro Atomico Bariloche (Argentina); Dodat, Diego; Casas, Oscar R. [CITOMA, Fundacion Avanzar, Instituto de Terapia Radiante S.A., CIO La Plata (Argentina); Gonzalez, Monica C., E-mail: gonzalez@inifta.unlp.edu.ar [UNLP, INIFTA, Departamento de Quimica, Facultad de Ciencias Exactas (Argentina); Kotler, Monica L., E-mail: kotler@qb.fcen.uba.ar [University of Buenos Aires, Departamento de Quimica Biologica, Facultad de Ciencias Exactas y Naturales, UBA (Argentina)

    2012-03-15

    The capability of silicon nanoparticles to increase the yield of reactive species upon 4 MeV X-ray irradiation of aqueous suspensions and C6 glioma cell cultures was investigated. ROS generation was detected and quantified using several specific probes. The particles were characterized by FTIR, XPS, TEM, DLS, luminescence, and adsorption spectroscopy before and after irradiation to evaluate the effect of high energy radiation on their structure. The total concentration of O{sub 2}{sup Bullet -}/HO{sub 2}{sup Bullet}, HO{sup Bullet}, and H{sub 2}O{sub 2} generated upon 4-MeV X-ray irradiation of 6.4 {mu}M silicon nanoparticle aqueous suspensions were on the order of 10 {mu}M per Gy, ten times higher than that obtained in similar experiments but in the absence of particles. Cytotoxic {sup 1}O{sub 2} was generated only in irradiation experiments containing the particles. The particle surface became oxidized to SiO{sub 2} and the luminescence yield reduced with the irradiation dose. Changes in the surface morphology did not affect, within the experimental error, the yields of ROS generated per Gy. X-ray irradiation of glioma C6 cell cultures with incorporated silicon nanoparticles showed a marked production of ROS proportional to the radiation dose received. In the absence of nanoparticles, the cells showed no irradiation-enhanced ROS generation. The obtained results indicate that silicon nanoparticles of <5 nm size have the potential to be used as radiosensitizers for improving the outcomes of cancer radiotherapy. Their capability of producing {sup 1}O{sub 2} upon X-ray irradiation opens novel approaches in the design of therapy strategies.

  14. PFGE analysis of DNA double-strand breaks and DNA repair process in human osteosarcoma cells irradiated by X-ray

    International Nuclear Information System (INIS)

    Cao Jianping; Majima, H.; Yamaguchi, C.

    2000-01-01

    Objective: To study the induction of DNA double-strand breaks (DSBs) in human osteosarcoma cells irradiated by X-ray, the DNA DSBs repair process and the tumour cell radiosensitivity. Methods: Two cell lines of human osteosarcoma, Rho0 and 143. B were used. Initial DNA damage of DSBs by X-ray irradiation was measured using clamped homogeneous electrical field (CHEF) electrophoresis. Results: X-ray-induced DNA DSBs of human osteosarcoma cells after CHEF-electrophoresis increased linearly with the irradiation dose between 0 and 50 Gy. The repair of DNA DSBs in human osteosarcoma cells increased with the post-irradiation incubation time. In contrast to 14.3B cell line at the same dose point, much more DNA DSBs were induced in Rho0 cell line after X-ray irradiation. Conclusion: CHEF pulsed-field gel electrophoresis (PEGE) is a sensitive method for the determination of radiation-induced DNA DSBs in high molecular weight DNA of human osteosarcoma cells. Radiation-induced DNA DSBs of osteosarcoma increase with the dose in a linear manner. After incubation, both Rho0 cell line and 143. B cell line can repair the DNA DSBs. Between two cell lines of human osteosarcoma, Rho0 and 143.B, Rho0 cell line is more sensitive to ionizing radiation than 143.B line

  15. Realization of radiobiological in vitro cell experiments at conventional X-ray tubes and unconventional radiation sources

    International Nuclear Information System (INIS)

    Beyreuther, Elke

    2010-01-01

    More than hundred years after the discovery of X-rays different kinds of ionizing radiation are ubiquitous in medicine, applied to clinical diagnostics and cancer treatment as well. Irrespective of their nature, the widespread application of radiation implies its precise dosimetric characterization and detailed knowledge of the radiobiological effects induced in cancerous and normal tissue. Starting with in vitro cell irradiation experiments, which define basic parameters for the subsequent tissue and animal studies, the whole multi-stage process is completed by clinical trials that translate the results of fundamental research into clinical application. In this context, the present dissertation focuses on the establishment of radiobiological in vitro cell experiments at unconventional, but clinical relevant radiation qualities. In the first part of the present work the energy dependent biological effectiveness of photons was studied examining low-energy X-rays (≤ 50 keV), as used for mammography, and high-energy photons (≥ 20 MeV) as proposed for future radiotherapy. Cell irradiation experiments have been performed at conventional X-ray tubes providing low-energy photons and 200 kV reference radiation as well. In parallel, unconventional quasi-monochromatic channeling X-rays and high-energy bremsstrahlung available at the radiation source ELBE of the Forschungszentrum Dresden-Rossendorf were considered for radiobiological experimentation. For their precise dosimetric characterization dosimeters based on the thermally stimulated emission of exoelectrons and on radiochromic films were evaluated, whereas just the latter was found to be suitable for the determination of absolute doses and spatial dose distributions at cell position. Standard ionization chambers were deployed for the online control of cell irradiation experiments. Radiobiological effects were analyzed in human mammary epithelial cells on different subcellular levels revealing an increasing amount

  16. Realization of radiobiological in vitro cell experiments at conventional X-ray tubes and unconventional radiation sources

    Energy Technology Data Exchange (ETDEWEB)

    Beyreuther, Elke

    2010-09-10

    More than hundred years after the discovery of X-rays different kinds of ionizing radiation are ubiquitous in medicine, applied to clinical diagnostics and cancer treatment as well. Irrespective of their nature, the widespread application of radiation implies its precise dosimetric characterization and detailed knowledge of the radiobiological effects induced in cancerous and normal tissue. Starting with in vitro cell irradiation experiments, which define basic parameters for the subsequent tissue and animal studies, the whole multi-stage process is completed by clinical trials that translate the results of fundamental research into clinical application. In this context, the present dissertation focuses on the establishment of radiobiological in vitro cell experiments at unconventional, but clinical relevant radiation qualities. In the first part of the present work the energy dependent biological effectiveness of photons was studied examining low-energy X-rays (≤ 50 keV), as used for mammography, and high-energy photons (≥ 20 MeV) as proposed for future radiotherapy. Cell irradiation experiments have been performed at conventional X-ray tubes providing low-energy photons and 200 kV reference radiation as well. In parallel, unconventional quasi-monochromatic channeling X-rays and high-energy bremsstrahlung available at the radiation source ELBE of the Forschungszentrum Dresden-Rossendorf were considered for radiobiological experimentation. For their precise dosimetric characterization dosimeters based on the thermally stimulated emission of exoelectrons and on radiochromic films were evaluated, whereas just the latter was found to be suitable for the determination of absolute doses and spatial dose distributions at cell position. Standard ionization chambers were deployed for the online control of cell irradiation experiments. Radiobiological effects were analyzed in human mammary epithelial cells on different subcellular levels revealing an increasing amount

  17. MRI features of myositis ossificans with X-ray and CT findings

    International Nuclear Information System (INIS)

    Gu Xiang; Bai Rongjie; Qu Hui; Cheng Xiaoguang; Li Yuang

    2009-01-01

    Objective: To investigate the MRI features of myositis ossificans, and to address the correlation with X-ray radiography and CT findings. Methods: X-ray films, CT and MRI of 36 documented cases of myositis ossificans were retrospectively analyzed, and the literatures were reviewed. Results: Of the 36 cases, 4 cases occurred in the elbow joint, 4 in the shoulder joint, 15 in the hip joint, 6 in the tibiofibula, 5 in the femur, 1 in the metatarsal bones, and 1 in the ilium, respectively. Irregular patchy or lamellar high density calcification or ossification could be seen in the soft tissue parenchym on X-ray films and CT scan. Cortical bone integrity was preserved in diaphysis. CT enhanced scan showed that the swollen parenchyma was not enhanced and there was no parenchyma mass. On the early and middle stages, MR T 1 WI and T 2 WI showed slice-shaped low signal in the peripheral parenchyma, but patchy high signal was found around the low signal on T 2 WI. STIR showed mixed high and low signals in the swollen parenchyma with unclear demarcation. The lesions showed low signal on MR T 1 WI and T 2 WI in the late stage, and there was no edema in peripheral parenehyma. MRI enhanced scan found that the swollen parenchyma showed no enhancement in all stages. Conclusions: The imaging features of myositis ossificans have some characteristics. Misdiagnosis could be avoided when the disease was evaluated with the course. (authors)

  18. Differential expression of genome in the progeny doubling 40 generations of normal human liver cells irradiated by 60Co γ rays

    International Nuclear Information System (INIS)

    Zuo Yahui; Wang Fang; Geng Xiaohua; Wang Xiaoli; Li Jianguo; Wang Zhongwen; Tong Jian

    2008-01-01

    In order to investigate the differential expression of genome in nomal human liver cell irradiated by 60 Co γ rays, cDNA chip was applied to assay the alterations of transcriptional profile of nomal human liver cell'rogeny exposed to 4 Gy and 8 Gy of γ ray from 60 Co. Then Quantitative real-time PCR was used to confirm the commonly changed genes including VTN and INSIG1. The results demonstrated that the transcription level of 58 genes changed in the progeny of survival cells irradiated by 4 Gy γ rays, while 882 genes changed in the progeny of survival cells irradiated by 8 Gy γ rays. 16 genes changed in these cells irradiated by both 4 and 8 Gy γ rays. The transcription level was correlated to the original irradiation dose. Most of the genes were associated with transduction, cell cycle regulation, cellular immunity, cytoskeleton and movement, cell replication and repair mechanism, etc. The changed transcriptional level was further confirmed by RT-PCR assay for some of these genes. The results showed that differential expression of genome irradiated by different doses of γ rays. These results offer the fundamental materials for the research of genomic instability induced by radiation on the molecular level. (authors)

  19. Fully automatized renal parenchyma volumetry using a support vector machine based recognition system for subject-specific probability map generation in native MR volume data

    Science.gov (United States)

    Gloger, Oliver; Tönnies, Klaus; Mensel, Birger; Völzke, Henry

    2015-11-01

    In epidemiological studies as well as in clinical practice the amount of produced medical image data strongly increased in the last decade. In this context organ segmentation in MR volume data gained increasing attention for medical applications. Especially in large-scale population-based studies organ volumetry is highly relevant requiring exact organ segmentation. Since manual segmentation is time-consuming and prone to reader variability, large-scale studies need automatized methods to perform organ segmentation. Fully automatic organ segmentation in native MR image data has proven to be a very challenging task. Imaging artifacts as well as inter- and intrasubject MR-intensity differences complicate the application of supervised learning strategies. Thus, we propose a modularized framework of a two-stepped probabilistic approach that generates subject-specific probability maps for renal parenchyma tissue, which are refined subsequently by using several, extended segmentation strategies. We present a three class-based support vector machine recognition system that incorporates Fourier descriptors as shape features to recognize and segment characteristic parenchyma parts. Probabilistic methods use the segmented characteristic parenchyma parts to generate high quality subject-specific parenchyma probability maps. Several refinement strategies including a final shape-based 3D level set segmentation technique are used in subsequent processing modules to segment renal parenchyma. Furthermore, our framework recognizes and excludes renal cysts from parenchymal volume, which is important to analyze renal functions. Volume errors and Dice coefficients show that our presented framework outperforms existing approaches.

  20. Fully automatized renal parenchyma volumetry using a support vector machine based recognition system for subject-specific probability map generation in native MR volume data

    International Nuclear Information System (INIS)

    Gloger, Oliver; Völzke, Henry; Tönnies, Klaus; Mensel, Birger

    2015-01-01

    In epidemiological studies as well as in clinical practice the amount of produced medical image data strongly increased in the last decade. In this context organ segmentation in MR volume data gained increasing attention for medical applications. Especially in large-scale population-based studies organ volumetry is highly relevant requiring exact organ segmentation. Since manual segmentation is time-consuming and prone to reader variability, large-scale studies need automatized methods to perform organ segmentation. Fully automatic organ segmentation in native MR image data has proven to be a very challenging task. Imaging artifacts as well as inter- and intrasubject MR-intensity differences complicate the application of supervised learning strategies. Thus, we propose a modularized framework of a two-stepped probabilistic approach that generates subject-specific probability maps for renal parenchyma tissue, which are refined subsequently by using several, extended segmentation strategies. We present a three class-based support vector machine recognition system that incorporates Fourier descriptors as shape features to recognize and segment characteristic parenchyma parts. Probabilistic methods use the segmented characteristic parenchyma parts to generate high quality subject-specific parenchyma probability maps. Several refinement strategies including a final shape-based 3D level set segmentation technique are used in subsequent processing modules to segment renal parenchyma. Furthermore, our framework recognizes and excludes renal cysts from parenchymal volume, which is important to analyze renal functions. Volume errors and Dice coefficients show that our presented framework outperforms existing approaches. (paper)

  1. Adaptive Response to ionizing Radiation Induced by Low Doses of Gamma Rays in Human Lymphoblastoid Cell Lines

    International Nuclear Information System (INIS)

    Seong, Jin Sil; Suh, Chang Ok; Kim, Gwi Eon

    1994-01-01

    When cells are exposed to low doses of a mutagenic or clastogenic agents, they often become less sensitive to the effects of a higher does administered subsequently. Such adaptive responses were first described in Escherichia coli and mammalian cells to low doses of an alkylating agent. Since most of the studies have been carried out with human lymphocytes, it is urgently necessary to study this effect in different cellular systems. Its relation with inherent cellular radiosensitivity and underlying mechanism also remain to be answered. In this study, adaptive response by 1 cGy of gamma rays was investigated in three human lymphoblastoid cell lines which were derived from ataxia telangiectasia homozygote, ataxia telangiectasia heterozygote, and normal individual. Experiments were carried out by delivering 1 cGy followed by 50 cGy of gamma radiation and chromatid breaks were scored as an endpoint. The results indicate that prior exposure to 1 cGy of gamma rays reduces the number of chromatid breaks induced by subsequent higher does (50 cGy). The expression of this adaptive response was similar among three cell lines despite of their different radiosensitivity. When 3-aminobenzamide, an inhibitor of poly (ADP-ribose) polymerase, was added after 50 cGy, adaptive responses were abolished in all the tested cell lines. Therefore it is suggested that the adaptive response can be observed in human lymphoblastoid cell lines. Which was first documented through this study. The expression of adaptive response was similar among the cell lines regardless of their radiosensitivity. The elimination of the adaptive response by 3-aminobenzamide is consistent with the proposal that this adaptive response is the result of the induction of a certain chromosomal repair mechanism

  2. Pt and Ru X-ray absorption spectroscopy of PtRu anode catalysts in operating direct methanol fuel cells.

    Science.gov (United States)

    Stoupin, Stanislav; Chung, Eun-Hyuk; Chattopadhyay, Soma; Segre, Carlo U; Smotkin, Eugene S

    2006-05-25

    In situ X-ray absorption spectroscopy, ex situ X-ray fluorescence, and X-ray powder diffraction enabled detailed core analysis of phase segregated nanostructured PtRu anode catalysts in an operating direct methanol fuel cell (DMFC). No change in the core structures of the phase segregated catalyst was observed as the potential traversed the current onset potential of the DMFC. The methodology was exemplified using a Johnson Matthey unsupported PtRu (1:1) anode catalyst incorporated into a DMFC membrane electrode assembly. During DMFC operation the catalyst is essentially metallic with half of the Ru incorporated into a face-centered cubic (FCC) Pt alloy lattice and the remaining half in an amorphous phase. The extended X-ray absorption fine structure (EXAFS) analysis suggests that the FCC lattice is not fully disordered. The EXAFS indicates that the Ru-O bond lengths were significantly shorter than those reported for Ru-O of ruthenium oxides, suggesting that the phases in which the Ru resides in the catalysts are not similar to oxides.

  3. Microbeam X-ray fluorescence mapping of Cu and Fe in human prostatic carcinoma cell lines using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Rocha, K.M.J.; Leitao, R.G.; Oliveira-Barros, E.G.; Oliveira, M.A.; Canellas, C.G.L.; Anjos, M.J.; Nasciutti, L.E.; Lopes, R.T., E-mail: kjose@nuclear.ufrj.br, E-mail: marcelin@lin.ufrj.br, E-mail: ricardo@lin.ufrj.br, E-mail: roberta@lin.ufrj.br, E-mail: eligouveab@gmail.com, E-mail: maria_aparecida_ufrj@yahoo.com.br, E-mail: luiz.nasciutti@histo.ufrj.br, E-mail: roberta.leitao@uerj.br, E-mail: marcelin@uerj.br [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Laboratorio de Instrumentacao Nuclear; Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Instituto de Ciencias Biomedicas; Universidade do Estado do Rio de Janeiro (UERJ), RJ (Brazil). Instituto de Fisica

    2017-11-01

    Cancer is a worldwide public health problem and prostate cancer continues to be one of the most common fatal cancers in men. Copper plays an important role in the aetiology and growth of tumours however, whether intratumoral copper is actually elevated in prostate cancer patients has not been established. Iron, an important trace element, plays a vital function in oxygen metabolism, oxygen uptake, and electron transport in mitochondria, energy metabolism, muscle function, and hematopoiesis. The X-ray microfluorescence technique (μXRF) is a rapid and non-destructive method of elemental analysis that provides useful elemental information about samples without causing damage or requiring extra sample preparations. This study investigated the behavior of cells in spheroids of human prostate cells, tumour cell line (DU145) and normal cell line (RWPE-1), after supplementation with zinc chloride by 24 hours using synchrotron X-ray microfluorescence (μSRXRF). The measurements were performed with a standard geometry of 45 deg of incidence, excited by a white beam using a pixel of 25 μm and a time of 300 ms/pixel at the XRF beamline at the Synchrotron Light National Laboratory (Campinas, Brazil). The results by SRμXRF showed non-uniform Cu and Fe distributions in all the spheroids analyzed. (author)

  4. Microbeam X-ray fluorescence mapping of Cu and Fe in human prostatic carcinoma cell lines using synchrotron radiation

    International Nuclear Information System (INIS)

    Rocha, K.M.J.; Leitao, R.G.; Oliveira-Barros, E.G.; Oliveira, M.A.; Canellas, C.G.L.; Anjos, M.J.; Nasciutti, L.E.; Lopes, R.T.; Universidade Federal do Rio de Janeiro; Universidade do Estado do Rio de Janeiro

    2017-01-01

    Cancer is a worldwide public health problem and prostate cancer continues to be one of the most common fatal cancers in men. Copper plays an important role in the aetiology and growth of tumours however, whether intratumoral copper is actually elevated in prostate cancer patients has not been established. Iron, an important trace element, plays a vital function in oxygen metabolism, oxygen uptake, and electron transport in mitochondria, energy metabolism, muscle function, and hematopoiesis. The X-ray microfluorescence technique (μXRF) is a rapid and non-destructive method of elemental analysis that provides useful elemental information about samples without causing damage or requiring extra sample preparations. This study investigated the behavior of cells in spheroids of human prostate cells, tumour cell line (DU145) and normal cell line (RWPE-1), after supplementation with zinc chloride by 24 hours using synchrotron X-ray microfluorescence (μSRXRF). The measurements were performed with a standard geometry of 45 deg of incidence, excited by a white beam using a pixel of 25 μm and a time of 300 ms/pixel at the XRF beamline at the Synchrotron Light National Laboratory (Campinas, Brazil). The results by SRμXRF showed non-uniform Cu and Fe distributions in all the spheroids analyzed. (author)

  5. Correlations of DNA strand breaks and their repair with cell survival following acute exposure to mercury(II) and X-rays

    International Nuclear Information System (INIS)

    Cantoni, O.; Costa, M.

    1983-01-01

    Alkaline elution analysis demonstrates that both HgCl 2 and X-rays result in a rapid induction of DNA single-strand breaks at acutely cytotoxic doses (HgCl 2 , 25-100 microM for 60 min; X-rays, 150-600 rads) in cultured Chinese hamster ovary cells. Cytotoxicity, as measured by cell-plating efficiency, correlates linearly with the level of DNA breakage induced by both agents (HgCl 2 , r . 0.97; X-rays, r . 0.99), although a substantial difference in axis intercepts of the two linear regression lines indicates that a higher level of DNA damage was required by X-rays as compared with HgCl 2 to produce an equivalent level of cell killing. DNA damage induced by X-rays was rapidly repaired such that within 1 hr following treatment the elution rate of DNA from treated cells resembled that obtained in untreated cultures. In contrast, DNA damage after Hg 2+ insult was not repaired, and further damage was evident following a similar 1-hr recovery period. Addition of noncytotoxic, non-DNA-damaging concentrations of HgCl 2 (10 microM) to cells 15-45 min following treatment with X-rays greatly inhibited the repair of the DNA strand breaks. Thus, although both HgCl 2 and X-rays induce rapid and striking single-strand breaks in the DNA, persistence of Hg 2+ in the cell can inhibit the repair of these breaks. The inhibition of DNA repair by HgCl 2 may explain why this agent is not severely mutagenic or carcinogenic despite its ability to induce an X-ray-like DNA damage and why a lower level of mercury-induced DNA damage, compared with that induced by X-rays, was required to produce an equivalent level of cell death

  6. Analysis of cell-cycle regulation following exposure of lung-derived cells to γ-rays

    Science.gov (United States)

    Trani, D.; Lucchetti, C.; Cassone, M.; D'Agostino, L.; Caputi, M.; Giordano, A.

    Acute exposure of mammalian cells to ionizing radiation results in a delay of cell-cycle progression and/or augmentation of apoptosis. Following ionizing radiation-induced DNA damage, cell-cycle arrest in the G1- or G2-phase of the cell-cycle prevents or delays DNA replication or mitosis, providing time for the DNA repair machinery to exert its function. Deregulation or failing of cell-cycle checkpoints and/or DNA repair mechanisms may lead normal cells bearing chromosome mutations to acquire neoplastic autonomy, which in turn can trigger the onset of cancer. Existing studies have focused on the impact of p53 status on the radiation response of lung cancer (LC) cell lines in terms of both cell-cycle regulation and apoptosis, while no comparative studies have been performed on the radiation response of lung derived normal and cancerous epithelial cells. To investigate the radiation response in normal and cancerous phenotypes, along with the role and impact of p53 status, and possible correlations with pRb/p105 or other proteins involved in carcinogenesis and cell-cycle regulation, we selected two lung-derived epithelial cell lines, one normal (NL20, p53 wild-type) and one non-small cell lung cancer (NSCLC), H358 (known to be p53-deficient). We compared the levels of γ-induced cell proliferation ability, cell-cycle arrest, apoptotic index, and expression levels of cell-cycle regulating and regulated proteins. The different cell sensitivity, apoptotic response and protein expression profiles resulting from our study for NL20 and H358 cells suggest that still unknown mechanisms involving p53, pRb/p105 and their target molecules might play a pivotal role in determining cell sensitivity and resistance upon exposure to ionizing radiation.

  7. Free radical scavenger edaravone suppresses X-ray-induced apoptosis through p53 inhibition in MOLT-4 cells

    International Nuclear Information System (INIS)

    Sasano, Nakashi; Shiraishi, Kenshiro; Igaki, Hiroshi; Nakagawa, Keiichi; Enomoto, Atsushi; Hosoi, Yoshio; Matsumoto, Yoshihisa; Miyagawa, Kiyoshi; Katsumura, Yosuke

    2007-01-01

    Edaravone, a clinical drug used widely for the treatment of acute cerebral infarction, is reported to scavenge free radicals. In the present study, we investigated the radioprotective effect of edaravone on X-ray-induced apoptosis in MOLT-4 cells. Apoptosis was determined by the dye exclusion test, Annexin V binding assay, cleavage of caspase, and DNA fragmentation. We found that edaravone significantly suppressed the X-ray-induced apoptosis. The amount of intracellular reactive oxygen species (ROS) production was determined by the chloromethyl-2', 7'-dichlorodihydro-fluorescein diacetate system. We found that the intracellular ROS production by X-irradiation was completely suppressed by the addition of edaravone. The accumulation and phosphorylation of p53 and the expression of p21 WAF1 , a target protein of p53, which were induced by X-irradiation, were also suppressed by adding edaravone. We conclude that the free radical scavenger edaravone suppresses X-ray-induced apoptosis in MOLT-4 cells by inhibiting p53. (author)

  8. Free radical scavenger edaravone suppresses X-ray-induced apoptosis through p53 inhibition in MOLT-4 cells

    Energy Technology Data Exchange (ETDEWEB)

    Sasano, Nakashi; Shiraishi, Kenshiro; Igaki, Hiroshi; Nakagawa, Keiichi [Tokyo Univ., Graduate School of Medicine, Tokyo (Japan); Enomoto, Atsushi; Hosoi, Yoshio; Matsumoto, Yoshihisa; Miyagawa, Kiyoshi [Tokyo Univ., Faculty of Medicine, Tokyo (Japan); Katsumura, Yosuke [Tokyo Univ., Graduate School of Engineering, Tokyo (Japan)

    2007-11-15

    Edaravone, a clinical drug used widely for the treatment of acute cerebral infarction, is reported to scavenge free radicals. In the present study, we investigated the radioprotective effect of edaravone on X-ray-induced apoptosis in MOLT-4 cells. Apoptosis was determined by the dye exclusion test, Annexin V binding assay, cleavage of caspase, and DNA fragmentation. We found that edaravone significantly suppressed the X-ray-induced apoptosis. The amount of intracellular reactive oxygen species (ROS) production was determined by the chloromethyl-2', 7'-dichlorodihydro-fluorescein diacetate system. We found that the intracellular ROS production by X-irradiation was completely suppressed by the addition of edaravone. The accumulation and phosphorylation of p53 and the expression of p21{sup WAF1}, a target protein of p53, which were induced by X-irradiation, were also suppressed by adding edaravone. We conclude that the free radical scavenger edaravone suppresses X-ray-induced apoptosis in MOLT-4 cells by inhibiting p53. (author)

  9. Cone-beam X-ray phase-contrast tomography for the observation of single cells in whole organs

    International Nuclear Information System (INIS)

    Krenkel, Martin

    2015-01-01

    X-ray imaging enables the nondestructive investigation of interior structures in otherwise opaque samples. In particular the use of computed tomography (CT) allows for arbitrary virtual slices through the object and 3D information about intricate structures can be obtained. However, when it comes to image very small structures like single cells, the classical CT approach is limited by the weak absorption of soft-tissue. The use of phase information, encoded in measureable intensity images by free-space propagation of coherent X-rays, allows a huge increase in contrast, which enables 3D reconstructions at higher resolutions. In this work the application of propagation-based phase-contrast tomography to lung tissue samples is demonstrated in close to in vivo conditions. Reconstructions of the lung structure of whole mice at down to 5 µm resolution are obtained at a selfbuilt CT setup, which is based on a liquid-metal jet X-ray source. To reach even higher resolutions, synchrotron radiation in combination with suitable holographic phase-retrieval algorithms is employed. Due to optimized cone-beam geometry, field of view and resolution can be varied over a wide range of parameters, so that information on different length scales can be achieved, covering several millimeters field of view down to a 3D resolution of 50 nm. Thus, the sub-cellular 3D imaging of single cells embedded in large pieces of tissue is enabled, which paves the way for future biomedical research.

  10. Stage sensitivity and dose response of meiotic chromosomes of pollen mother cells of Tradescantia to X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Ma, T H; Kontos, Jr, G J; Anderson, V A [Western Illinois Univ., Macomb (USA). Dept. of Biological Sciences

    1980-05-01

    Chromosome damage induced by physical and chemical mutagens can be quantitated by the frequencies of micronuclei (MCN) produced in tetrads of the meiotic pollen mother cells of Tradescantia, i.e. the 'MCN-in-Tetrad' test. The stage sensitivity and dose response of these meiocytes to low exposures of X-rays was studied to improve the efficiency and reliability of this test. Stage sensitivity was determined by observing, at 3 hr intervals, the frequencies of X-ray (35 rads)-induced MCN in tetrads from a series of 16 fixations of tetrad-containing inflorescences. Late stages of meiosis (3-9 hr post-irradiation fixation groups) were insensitive (5-14 MCN/100 tetrads). Relatively high sensitivity was exhibited in the early stages of meiosis. The first and second sensitive peaks (62 and 61 MCN/100 tetrads) centered around the 21 and 39 hr post-irradiation fixation groups respectively. Control groups yielded around 3-4 MCN/100 tetrads. A dose-response relation for MCN was determined by treating early stages of meiotic pollen mother cells with X-ray exposures ranging from 9.5 to 57.5 rads. A linear regression line was established with about 20 MCN/100 tetrads per 10 rad increment.

  11. Stage sensitivity and dose response of meiotic chromosomes of pollen mother cells of Tradescantia to X-rays

    International Nuclear Information System (INIS)

    Ma, T.-H.; Kontos, G.J. Jr.; Anderson, V.A.

    1980-01-01

    Chromosome damage induced by physical and chemical mutagens can be quantitated by the frequencies of micronuclei (MCN) produced in tetrads of the meiotic pollen mother cells of Tradescantia, i.e. the 'MCN-in-Tetrad' test. The stage sensitivity and dose response of these meiocytes to low exposures of X-rays was studied to improve the efficiency and reliability of this test. Stage sensitivity was determined by observing, at 3 hr intervals, the frequencies of X-ray (35 rads)-induced MCN in tetrads from a series of 16 fixations of tetrad-containing inflorescences. Late stages of meiosis (3-9 hr post-irradiation fixation groups) were insensitive (5-14 MCN/100 tetrads). Relatively high sensitivity was exhibited in the early stages of meiosis. The first and second sensitive peaks (62 and 61 MCN/100 tetrads) centered around the 21 and 39 hr post-irradiation fixation groups respectively. Control groups yielded around 3-4 MCN/100 tetrads. A dose-response relation for MCN was determined by treating early stages of meiotic pollen mother cells with X-ray exposures ranging from 9.5 to 57.5 rads. A linear regression line was established with about 20 MCN/100 tetrads per 10 rad increment. (author)

  12. Imaging cells and sub-cellular structures with ultrahigh resolution full-field X-ray microscopy.

    Science.gov (United States)

    Chien, C C; Tseng, P Y; Chen, H H; Hua, T E; Chen, S T; Chen, Y Y; Leng, W H; Wang, C H; Hwu, Y; Yin, G C; Liang, K S; Chen, F R; Chu, Y S; Yeh, H I; Yang, Y C; Yang, C S; Zhang, G L; Je, J H; Margaritondo, G

    2013-01-01

    Our experimental results demonstrate that full-field hard-X-ray microscopy is finally able to investigate the internal structure of cells in tissues. This result was made possible by three main factors: the use of a coherent (synchrotron) source of X-rays, the exploitation of contrast mechanisms based on the real part of the refractive index and the magnification provided by high-resolution Fresnel zone-plate objectives. We specifically obtained high-quality microradiographs of human and mouse cells with 29 nm Rayleigh spatial resolution and verified that tomographic reconstruction could be implemented with a final resolution level suitable for subcellular features. We also demonstrated that a phase retrieval method based on a wave propagation algorithm could yield good subcellular images starting from a series of defocused microradiographs. The concluding discussion compares cellular and subcellular hard-X-ray microradiology with other techniques and evaluates its potential impact on biomedical research. Copyright © 2012 Elsevier Inc. All rights reserved.

  13. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    International Nuclear Information System (INIS)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-01-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53δ, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53δ cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of undifferentiated

  14. The effect of caffeine on p53-dependent radioresponses in undifferentiated mouse embryonal carcinoma cells after X-ray and UV-irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Taga, Masataka; Shiraishi, Kazunori; Shimura, Tsutomu; Uematsu, Norio; Kato, Tomohisa; Niwa, Ohtsura [Kyoto Univ. (Japan). Radiation Biology Center; Nishimune, Yoshitake; Aizawa, Shinichi; Oshimura, Mitsuo

    2000-09-01

    The effect of caffeine was studied on the radioresponses of undifferentiated mouse embryonal carcinoma cells (EC cells) with or without the functional p53. The radioresponses studied included radiosensitivity, the activation of p53, apoptosis with characteristic DNA ladder formation and cell cycle progression. An undifferentiated mouse EC cell line, ECA2, and a newly established p53-deficient EC cell line, p53{delta}, were used in the present study. The status of the p53 gene did not significantly affect the colony survivals of undifferentiated EC cells to X-rays and UV. Although a post-irradiation treatment with caffeine sensitized both lines to X-rays marginally, the sensitization was prominent for UV regardless of the p53 status of the cells. The activation of a p53 responsible lacZ reporter construct was observed in stably transfected ECA2 cells after X-ray and UV irradiations. Caffeine suppressed the X-ray induced activation of the lacZ reporter, while it drastically enhanced the activation after UV irradiation. X-rays and UV readily triggered the apoptosis of ECA2 cells with the characteristic DNA ladder. Although UV-induced DNA ladder formation was enhanced by caffeine, that induced by X-rays was unaffected. Therefore, the effects of caffeine on the p53-dependent radioresponses were found to be agent specific: suppression for the X-ray induced and augmentation for the UV induced. In contrast to p53-proficient ECA2 cells, smear-like DNA degradation was observed for irradiated p53{delta} cells, suggesting the presence of a mode of cell death without DNA ladder formation. UV induction of the smear-like DNA degradation was enhanced in the presence of caffeine. Regardless of the state of the p53 gene, G1/S arrest was not observed in X-ray and UV irradiated EC cells. X-rays induced G2/M arrest in both lines, which was abrogated by caffeine, while G2/M arrest after UV was unaffected by a caffeine treatment. These results indicate that the radioresponses of

  15. The effect of x-ray irradiation on proliferation and differentiation of epithelial cells in mouse skin

    International Nuclear Information System (INIS)

    Tanabe, Akira

    1980-01-01

    To elucidate radiation injuries and the recovery mechanism of epithelial cells exposed to 150 R or 450 R of x-ray, the epidermal proliferative unit (EPU) in the backs of mice was analysed histologically and dynamically by measuring the labelled index of cells with 3 H-thymidine and measuring differentiation index of cells. EPU was normal for 6 days after irradiation with both 150 R and 450 R. However, partial hyperplasia and EPU disorders in a range consistent with hyperplasia appeared in segmented preparations 7 days after irradiation. Both doses inhibited cell differentiation for 5 days after irradiation. Cell proliferation, which was higher than the normal rate, peaked 7 days after irradiation with 150 R and 9 days after irradiation with 540 R. Cell proliferation returned to normal 10 days after irradiation. DNA synthesis was inhibited one day after irradiation with both 150 R and 450 R, but it returned to normal 3 days after irradiation. There was an overshoot of DNA synthesis, but synthesis returned to normal 9 days after irradiation with 150 R and 12 days after irradiation with 450 R. EPU disorders returned to normal according to normalization of cell differentiation and DNA synthesis. (Tsunoda, M.)

  16. Six-six (6-6) cell used in X-ray and neutron diffraction experiments under high pressure

    International Nuclear Information System (INIS)

    Nishiyama, Norimasa; Yamada, Akihiro

    2015-01-01

    At synchrotron radiation facilities and neutron experimental facilities, X-ray diffraction experiments and neutron diffraction experiments under high-pressure for large-capacity of samples are conducted using DIA type device and 6-axis pressure device that add pressure on cubic space. As the anvil assembly capable of mounting on the above two devices, MA6-6 cell has come to be used. This paper introduces the advantages of using MA6-6 cell, pressure region where experiment is possible with MA6-6 cell, and large-capacity high-pressure press beamline P61.2 that simulates MA-6-6 cell. At MA6-6 cell, 6 pieces of the first-stage anvils of DIA type device or 6-axis pressure device pressurize 6 pieces of the second-stage anvils. These second-stage anvils are included in MA6-6 anvil assembly. The greatest feature of MA6-6 cell is the adoption of the frame for taking alignment of the second stage anvils. By combining MA6-6 cell with DIA-type device or 6-axis pressure device, the degree of freedom of experiment increases, which can simplify the experimental setup. (A.O.)

  17. Transforming growth factor beta 1 expression and inflammatory cells in tooth extraction socket after X-ray irradiation

    Directory of Open Access Journals (Sweden)

    Ramadhan Hardani Putra

    2016-06-01

    Full Text Available Background: Radiographic examination is often used in dentistry to evaluate tooth extraction complications. X-ray used in radiographic examination, however, has negative effects, including damage to DNA and inflammatory response during wound healing process. Purpose: This study aimed to analyze the effects of X-ray irradiation on transforming growth factor beta 1 (TGF-ß1 expression and number of inflammatory cells in tooth extraction sockets. Method: Thirty rats were divided into three groups, which consist of control group (with a radiation of 0 mSv, treatment group 1 (with a radiation of 0.08 mSv, and treatment group 2 (with a radiation of 0.16 mSv. These rats in each group were sacrificed on days 3 and 5 after treatment. Inflammatory cells which were observed in this research were PMN, macrophages, and lymphocytes. Histopathological and immunohistochemical examinations were used to calculate the number of inflammatory cells and TGF-ß1 expression. Obtained data were analyzed using SPSS 16.0 software with one way ANOVA and Tukey’s HSD tests. Result: There was no significant decrease in the number of PMN. On the other hand, there were significant decreases in the number of macrophages and lymphocytes in the sacrificed group on day-5 with the radiation of 0.16 mSv. Similarly, the most significant decreased expression of TGF-ß1 was found in the group sacrificed on day 5 with the radiation of 0.16 mSv. Conclusion: X-ray irradiation with 0.08 mSv and 0.16 mSv doses can decrease TGF-ß1 expression and number of inflammatory cells in tooth extraction sockets on day 3 and 5 post extraction.

  18. Cell density dependence of transformation frequencies in C3H10T1/2 cells exposed to X-rays

    Energy Technology Data Exchange (ETDEWEB)

    Bettega, D; Calzolari, P; Ottolenghi, A; Lombardi, L T [Milan Univ. (Italy). Ist. di Fisica; Rimoldi, E [Milan Univ. (Italy). Ist. di Radiologia Veterinaria

    1989-12-01

    The effects of cell density on transformation frequencies were studied in C3H10T1/2 cells exposed to 0.5 and 7 Gy of 200 kVp X-rays. Initial cell density strongly influenced transformation frequency; this decreased by a factor of between 4 and 10 when the initial seeding density was changed from 50 to 2500 cells/10 cm diameter Petri dish. The data were fitted with two equations: (a) an allometric function represented on a log-log scale by a straight line and (b) a sigmoidal function with plateaux between 50 and 250 cells/dish and above 600. The two curves are compared and their probabilities discussed. Our data indicate that the region between 50 and 250 cells/dish would be the most suitable region for dose-effect measurements. A study of the growth curves at 0.5 and 8.5 Gy shows that cell growth rates are not influenced by initial cell density. (author).

  19. A temperature-controlled cell for X-ray study of liquid systems using a commercial DRON-UM1 diffractometer

    International Nuclear Information System (INIS)

    Petrun'kin, S.P.; Garavina, E.V.; Trostin, V.N.

    1995-01-01

    A container (cell) and a temperature-control system have been designed enabling one to carry out x-ray diffraction study of liquid samples both at a fixed temperature and within a certain temperature range using a commercial DRON-UMl x-ray diffractometer. Special features of the cell and the materials used for it allow one to study both chemically inert and corrosive liquids

  20. The morphofunctional state of Purkin'e cells in the cerebellum of new-born rats following laser and gamma-ray exposure

    International Nuclear Information System (INIS)

    Zubkova, S.M.; Popov, V.I.

    1993-01-01

    Following of local laser (632.8 nm, 6.3. J/cm 2 ) and whole-body Gy gamma-ray exposures of new-born rats the contrast changes of morphometrical indices, RNA amount, and chromatophilia of Purkin'e cells in the cerebellum were seen. The preliminary laser exposure of new-born rat cerebellum artially increased activity of karyogene structures of the cerebellum cells which were inhibited by 6.37 Gy gamma-rays

  1. Inhibition effect of proteasome inhibitor MG132 combined with X-ray irradiation on cell growth, metastasis and cycle distribution of human lung adenocarcinoma cells

    International Nuclear Information System (INIS)

    Liu Jing; Tang Yiting; Zhou Jundong; Zhang Shuyu; Cao Han; Wu Jinchang; Luo Judong; Chen Guanglie; Cao Jianping

    2014-01-01

    Objective: To study the effects of proteasome inhibitor MG132 on the growth, metastasis, and cell cycle distribution of human lung adenocarcinoma cells A549 irradiated by X-rays. Methods: After treatment of MG132 and irradiation,cell proliferation was detected by MTT assay. Survival was measured by clonogenic assay. Cell migration ability was detected by the Scratch migration assay. Cell invasion ability was detected by transwell migration assay. Cell cycle distribution were analyzed by flow cytometry assay. Protein expression was detected by Western blot assay. Results: MG132 alone inhibited cell growth in a dose-and time-dependent manner. MG132 in combination with radiation significantly suppressed the growth, migration and invasion of A549 cells compared to the control (F =554.78, 954.64, P<0.01). MG132 enhanced radiation-induced G 1 -arrest (t =4.44, 12.41, 3.52, 6.72, P<0.05). The G 1 cell cycle distribution rate of MG132 plus RT group was increased to (71.05 ± 4.17)%. The expressions of MMP-2, MMP-9 and Cyclin D1 were significantly suppressed by MG132 in combination with radiation, while the expression of P53 was up-regulated. Conclusions: MG132 inhibits cell growth, migration and invasion ability, and induces G 1 cell cycle arrest of A549 cells treated with MG132 in combination with radiation, in which the down-regulation of MMPs and Cyclin D1 and up-regulation of P53 may be involved. (authors)

  2. Synchrotron x-ray diffraction studies of the structural properties of electrode materials in operating battery cells

    International Nuclear Information System (INIS)

    Thurston, T.R.; Jisrawi, N.M.; Mukerjee, S.; Yang, X.Q.; McBreen, J.; Daroux, M.L.; Xing, X.K.

    1996-01-01

    Hard x rays from a synchrotron source were utilized in diffraction experiments which probed the bulk of electrode materials while they were operating in situ in battery cells. Two technologically relevant electrode materials were examined; an AB 2 -type anode in a nickel endash metal endash hydride cell and a LiMn 2 O 4 cathode in a Li-ion open-quote open-quote rocking chair close-quote close-quote cell. Structural features such as lattice expansions and contractions, phase transitions, and the formation of multiple phases were easily observed as either hydrogen or lithium was electrochemically intercalated in and out of the electrode materials. The relevance of this technique for future studies of battery electrode materials is discussed. copyright 1996 American Institute of Physics

  3. Combined use of atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry for cell surface analysis.

    Science.gov (United States)

    Dague, Etienne; Delcorte, Arnaud; Latgé, Jean-Paul; Dufrêne, Yves F

    2008-04-01

    Understanding the surface properties of microbial cells is a major challenge of current microbiological research and a key to efficiently exploit them in biotechnology. Here, we used three advanced surface analysis techniques with different sensitivity, probing depth, and lateral resolution, that is, in situ atomic force microscopy, X-ray photoelectron spectroscopy, and secondary ion mass spectrometry, to gain insight into the surface properties of the conidia of the human fungal pathogen Aspergillus fumigatus. We show that the native ultrastructure, surface protein and polysaccharide concentrations, and amino acid composition of three mutants affected in hydrophobin production are markedly different from those of the wild-type, thereby providing novel insight into the cell wall architecture of A. fumigatus. The results demonstrate the power of using multiple complementary techniques for probing microbial cell surfaces.

  4. Particle-in-cell simulations of multi-MeV pulsed X-ray induced air plasmas at low pressures

    International Nuclear Information System (INIS)

    Ribière, M.; D'Almeida, T.; Gaufridy de Dortan, F. de; Maulois, M.; Delbos, C.; Garrigues, A.; Cessenat, O.; Azaïs, B.

    2016-01-01

    A full kinetic modelling of the charge particles dynamics generated upon the irradiation of an air-filled cavity by a multi-MeV pulsed x-ray is performed. From the calculated radiative source generated by the ASTERIX generator, we calculated the electromagnetic fields generated by x-ray induced air plasmas in a metallic cavity at different pressures. Simulations are carried out based on a Particle-In-Cell interpolation method which uses 3D Maxwell-Vlasov calculations of the constitutive charged species densities of air plasmas at different pressures at equilibrium. The resulting electromagnetic fields within the cavity are calculated for different electron densities up to 4 × 10"1"0" cm"−"3. For each air pressure, we show electronic plasma waves formation followed by Landau damping. As electron density increases, the calculations exhibit space-charged neutralization and return current formation.

  5. Effect of remote ischemic postconditioning in inflammatory changes of the lung parenchyma of rats submitted to ischemia and reperfusion

    Directory of Open Access Journals (Sweden)

    Rafael Cantero Dorsa

    2015-09-01

    Full Text Available AbstractObjective:To assess the effects of postconditioning remote in ischemia-reperfusion injury in rat lungs.Methods:Wistar rats (n=24 divided into 3 groups: GA (I/R n=8, GB (R-Po n=8, CG (control n=8, underwent ischemia for 30 minutes artery occlusion abdominal aorta, followed by reperfusion for 60 minutes. Resected lungs and performed histological analysis and classification of morphological findings in accordance with the degree of tissue injury. Statistical analysis of the mean rating of the degree of tissue injury.Results:GA (3.6, GB (1.3 and CG (1.0. (GA GB X P<0.05.Conclusion:The remote postconditioning was able to minimize the inflammatory lesion of the lung parenchyma of rats undergoing ischemia and reperfusion process.

  6. Degradation and repair of DNA from rat hepatoma cells after treatments with γ-rays and N-methyl-N-nitrosourea

    International Nuclear Information System (INIS)

    Zakrzhevskaya, D.G.; Kulagina, T.P.; Petrov, S.I.; Fomenko, L.A.; Gaziev, A.I.

    1977-01-01

    It has been shown, that DNA single-strand breaks induced in the cells of ascite hepatoma with γ-rays and metylnitrosourea (MNM) are effectively repaired. DNA two-strand breaks of hepatoma cells, treated with MNM are effectively repaired in situ as well. Only insignificant part of two-strand gamma-induced breaks in DNA of these cells is repaired during postirradiation period. Under combined effect of gamma rays and MNM on hepatoma cells a delay of DNA reparation and its further degradation as well as inhibition of nonplanned DNA synthesis and the suppression of DNA-polymerase 1 activity are observed

  7. A Randomised Clinical Trial to Compare Coaxial and Noncoaxial Techniques in Percutaneous Core Needle Biopsy of Renal Parenchyma

    International Nuclear Information System (INIS)

    Babaei Jandaghi, Ali; Lebady, Mohammadkazem; Zamani, Athar-Alsadat; Heidarzadeh, Abtin; Monfared, Ali; Pourghorban, Ramin

    2017-01-01

    PurposeTo compare the coaxial and noncoaxial techniques of renal parenchymal core needle biopsy.Materials and MethodsThis is an institutional review board-approved randomised controlled trial comparing 83 patients (male, n = 49) who underwent renal parenchymal core biopsy with coaxial method and 83 patients (male, n = 40) with noncoaxial method. The rate of complications, the number of glomerular profiles, and the procedural time were evaluated in a comparison of the two methods. Correlation between the presence of renal parenchymal disease and the rate of complication was also evaluated.ResultsThe procedural time was significantly shorter in the coaxial technique (coaxial group, 5 ± 1 min; noncoaxial group, 14 ± 2 min; p < 0.001). The rates of complications for the coaxial method was significantly lower than the noncoaxial method (coaxial group, 10.8 %; noncoaxial group, 24.1 %; p = 0.025). There was no significant correlation between gender and the rate of complication. The number of glomerular profiles was significantly higher in patents who underwent renal biopsy with the coaxial method (coaxial group, 18.2 ± 9.1; noncoaxial group, 8.6 ± 5.5; p < 0.001). In the whole study population, the rate of complications was significantly higher in patients with a pathologic renal parenchyma compared to those with a normal parenchyma (19/71 vs. 10/95; p = 0.006).ConclusionsRenal parenchymal biopsy using a coaxial needle is a faster and safer method with a lower rate of complications.

  8. A Randomised Clinical Trial to Compare Coaxial and Noncoaxial Techniques in Percutaneous Core Needle Biopsy of Renal Parenchyma

    Energy Technology Data Exchange (ETDEWEB)

    Babaei Jandaghi, Ali [Guilan University of Medical Sciences, Department of Radiology, Poursina Hospital (Iran, Islamic Republic of); Lebady, Mohammadkazem; Zamani, Athar-Alsadat [Guilan University of Medical Sciences, Urology Research Center, Razi Hospital (Iran, Islamic Republic of); Heidarzadeh, Abtin [Guilan University of Medical Sciences, Department of Community Medicine (Iran, Islamic Republic of); Monfared, Ali [Guilan University of Medical Sciences, Urology Research Center, Razi Hospital (Iran, Islamic Republic of); Pourghorban, Ramin, E-mail: ramin-p2005@yahoo.com [Tehran University of Medical Sciences, Department of Radiology, Imam Khomeini Hospital Complex (Iran, Islamic Republic of)

    2017-01-15

    PurposeTo compare the coaxial and noncoaxial techniques of renal parenchymal core needle biopsy.Materials and MethodsThis is an institutional review board-approved randomised controlled trial comparing 83 patients (male, n = 49) who underwent renal parenchymal core biopsy with coaxial method and 83 patients (male, n = 40) with noncoaxial method. The rate of complications, the number of glomerular profiles, and the procedural time were evaluated in a comparison of the two methods. Correlation between the presence of renal parenchymal disease and the rate of complication was also evaluated.ResultsThe procedural time was significantly shorter in the coaxial technique (coaxial group, 5 ± 1 min; noncoaxial group, 14 ± 2 min; p < 0.001). The rates of complications for the coaxial method was significantly lower than the noncoaxial method (coaxial group, 10.8 %; noncoaxial group, 24.1 %; p = 0.025). There was no significant correlation between gender and the rate of complication. The number of glomerular profiles was significantly higher in patents who underwent renal biopsy with the coaxial method (coaxial group, 18.2 ± 9.1; noncoaxial group, 8.6 ± 5.5; p < 0.001). In the whole study population, the rate of complications was significantly higher in patients with a pathologic renal parenchyma compared to those with a normal parenchyma (19/71 vs. 10/95; p = 0.006).ConclusionsRenal parenchymal biopsy using a coaxial needle is a faster and safer method with a lower rate of complications.

  9. Nuclear scaffold organization in the X-ray sensitive Chinese hamster mutant cell line, xrs-5

    International Nuclear Information System (INIS)

    Yasui, L.S.; Fink, T.J.; Enrique, A.M.

    1994-01-01

    Nuclear organization was probed in the radiation-sensitive Chinese hamster ovary (CHO) cell line, xrs-5, and compared with parental CHO K1 cells using the resinless section technique and DNase I digestions. The resinless section data showed no gross morphological differences in core filaments from the nuclear scaffolds of unirradiated CHO K1 and xrs-5 cells. However, the nuclear scaffolds of irradiated xrs-5 cells (1 Gy) had significantly increased ground substance. Irradiated and unirradiated CHO K1 cell nuclear scaffolds were morphologically identical. These data suggest that both CHO K1 and xrs-5 cell nuclear scaffolds had internal nuclear scaffolding networks that could provide DNA attachment sites. (author)

  10. The value of ultrasonographic examinations in the diagnosis of focal changes in the hepatic parenchyma

    International Nuclear Information System (INIS)

    Narojek, T.

    1995-01-01

    The aim of the investigation was the comparison of the diagnostic value of the clinical, radiological and ultrasonographic examinations in the diagnosis of focal changes in the liver and the determination of the relations between the changes in the ultrasound image of the liver and the changes in other organs. The investigation was performed on 24 animals: 20 dogs and 4 cats of different breeds and sex, aged 1.5 to 14 years. The ultrasonographic examinations were done using the apparatus of Bruel and Kjaer type 1849 and Concept 2000 of Dynamic Imaging. The following changes were diagnosed in the ultrasonic picture: echogenic changes in 5 animals, hypoechogenic in 2 animals, normechogenic in 2 animals, hyperechogenic in 8 animals and changes of mixed echogenicity in 5 animals. The connection between clinical signs and the results of X-ray and ultrasonographic examination allowed the recognition of the changes in the liver as cysts, abscess and neoplasm of the liver. (author). 9 refs, 8 figs, 5 tabs

  11. Cell survival after the combined action of manganese (MnCl2) and X-rays in synchronized Chinese hamster cells

    International Nuclear Information System (INIS)

    Skreb, Y.; Nagy, B.

    1984-01-01

    The interactions between the effects of manganese chloride and X-rays were studied in synchronized populations of V79 Chinese hamster fibroblasts. The cells were selected by shaking off asynchronous cultures for detachment of mitotic cells which were plated in petri dishes and exposed to various treatments. Irradiati