WorldWideScience

Sample records for satellite cells fusing

  1. Smoothing of Fused Spectral Consistent Satellite Images

    DEFF Research Database (Denmark)

    Sveinsson, Johannes; Aanæs, Henrik; Benediktsson, Jon Atli

    2006-01-01

    on satellite data. Additionally, most conventional methods are loosely connected to the image forming physics of the satellite image, giving these methods an ad hoc feel. Vesteinsson et al. (2005) proposed a method of fusion of satellite images that is based on the properties of imaging physics...

  2. On-Orbit Performance of the Far Ultraviolet Spectroscopic Explorer (FUSE) Satellite

    CERN Document Server

    Sahnow, D J; Ake, T; Andersen, J; Andersson, B G; André, M; Artis, D; Berman, A; Blair, W; Brownsberger, K R; Calvani, H; Chayer, P; Conard, S; Feldman, P; Friedman, S; Fullerton, A W; Gaines, G; Gawne, W; Green, J; Gummin, M; Jennings, T; Joyce, J B; Kaiser, M E; Kruk, J W; Lindler, D; Massa, D L; Murphy, E; Oegerle, W R; Ohl, R; Roberts, B; Romelfanger, M; Roth, K C; Sankrit, R; Sembach, K R; Shelton, R; Siegmund, O; Silva, C; Sonneborn, G; Vaclavik, S; Weaver, H; Wilkinson, E

    2000-01-01

    Launch of the Far Ultraviolet Spectroscopic Explorer (FUSE) has been followed by an extensive period of calibration and characterization as part of the preparation for normal satellite operations. Major tasks carried out during this period include initial coalignment, focusing and characterization of the four instrument channels, and a preliminary measurement of the resolution and throughput performance of the instrument. We describe the results from this test program, and present preliminary estimates of the on-orbit performance of the FUSE satellite based on a combination of this data and prelaunch laboratory measurements.

  3. Satellite Cell Heterogeneity in Skeletal Muscle Homeostasis.

    Science.gov (United States)

    Tierney, Matthew T; Sacco, Alessandra

    2016-06-01

    The cellular turnover required for skeletal muscle maintenance and repair is mediated by resident stem cells, also termed satellite cells. Satellite cells normally reside in a quiescent state, intermittently entering the cell cycle to fuse with neighboring myofibers and replenish the stem cell pool. However, the mechanisms by which satellite cells maintain the precise balance between self-renewal and differentiation necessary for long-term homeostasis remain unclear. Recent work has supported a previously unappreciated heterogeneity in the satellite cell compartment that may underlie the observed variability in cell fate and function. In this review, we examine the work supporting this notion as well as the potential governing principles, developmental origins, and principal determinants of satellite cell heterogeneity.

  4. Technical report on galvanic cells with fused-salt electrolytes

    Science.gov (United States)

    Cairns, E. J.; Crouthamel, C. E.; Fischer, A. K.; Foster, M. S.; Hesson, J. C.; Johnson, C. E.; Shimotake, H.; Tevebaugh, A. D.

    1969-01-01

    Technical report is presented on sodium and lithium cells using fused salt electrolytes. It includes a discussion of the thermally regenerative galvanic cell and the secondary bimetallic cell for storage of electricity.

  5. Smoothing of Fused Spectral Consistent Satellite Images with TV-based Edge Detection

    DEFF Research Database (Denmark)

    Sveinsson, Johannes; Aanæs, Henrik; Benediktsson, Jon Atli

    2007-01-01

    Several widely used methods have been proposed for fusing high resolution panchromatic data and lower resolution multi-channel data. However, many of these methods fail to maintain the spectral consistency of the fused high resolution image, which is of high importance to many of the applications...... based on satellite data. Additionally, most conventional methods are loosely connected to the image forming physics of the satellite image, giving these methods an ad hoc feel. Vesteinsson et al. [1] proposed a method of fusion of satellite images that is based on the properties of imaging physics...... in a statistically meaningful way and was called spectral consistent panshapening (SCP). In this paper we improve this framework for satellite image fusion by introducing a better image prior, via data-dependent image smoothing. The dependency is obtained via total variation edge detection method....

  6. HEp-2 Cell Classification via Fusing Texture and Shape Information

    OpenAIRE

    Qi, Xianbiao; Zhao, Guoying; Li, Chun-Guang; Guo, Jun; Pietikäinen, Matti

    2015-01-01

    Indirect Immunofluorescence (IIF) HEp-2 cell image is an effective evidence for diagnosis of autoimmune diseases. Recently computer-aided diagnosis of autoimmune diseases by IIF HEp-2 cell classification has attracted great attention. However the HEp-2 cell classification task is quite challenging due to large intra-class variation and small between-class variation. In this paper we propose an effective and efficient approach for the automatic classification of IIF HEp-2 cell image by fusing ...

  7. Production of chicken chimeras by fusing blastodermal cells with electroporation

    Institute of Scientific and Technical Information of China (English)

    S.Aritomi; N.Fujihara

    2000-01-01

    Aim: To establish techniques for producing somatic and gennline chimeric chicken by transferring blastodennal cells fused with electroporation. Methods: Stage-X blastodermal cells isolated from freshly laid fertile unincubated white Leghom and Rhode Island red chicken eggs were fused with electroporation. The treated cell suspension was transferred to the recovery medium (DMEM containing 10% FBS) and was injected into the subgerminal cavity of recipient tmincubated embryos (stage X). Results: Of 177 recipient embryos injected with the fusing blastodermal cells, 6 (3.4%) survived to hatching. Somatic chimerism was examined in the melanocyte of the feather. The presence of feathers originating from the donor cell was observed in 1 bird (16.7%) out of the 6 hatched birds. After 21 days of incubation two birds out of five embryos were subjected to polymemse chain reaction (PCR) analysis for W-chromosome-specific DNA for each tissue. One bird possessed W-chromosome-specific DNA in the stomach, and the other exhibited the same DNA in the left and right gonads and other tissues, but not the stomach. Conclusion: Recipient embryo having electrofused blastodermal cells yields somatic and germline chimeric chickens more successfully.(Asian J Androl 2000 Dec;2:271-275)

  8. Active G protein-coupled receptors (GPCR), matrix metalloproteinases 2/9 (MMP2/9), heparin-binding epidermal growth factor (hbEGF), epidermal growth factor receptor (EGFR), erbB2, and insulin-like growth factor 1 receptor (IGF-1R) are necessary for trenbolone acetate-induced alterations in protein turnover rate of fused bovine satellite cell cultures.

    Science.gov (United States)

    Thornton, K J; Kamanga-Sollo, E; White, M E; Dayton, W R

    2016-06-01

    Trenbolone acetate (TBA), a testosterone analog, increases protein synthesis and decreases protein degradation in fused bovine satellite cell (BSC) cultures. However, the mechanism through which TBA alters these processes remains unknown. Recent studies indicate that androgens improve rate and extent of muscle growth through a nongenomic mechanism involving G protein-coupled receptors (GPCR), matrix metalloproteinases (MMP), heparin-binding epidermal growth factor (hbEGF), the epidermal growth factor receptor (EGFR), erbB2, and the insulin-like growth factor-1 receptor (IGF-1R). We hypothesized that TBA activates GPCR, resulting in activation of MMP2/9 that releases hbEGF, which activates the EGFR and/or erbB2. To determine whether the proposed nongenomic pathway is involved in TBA-mediated alterations in protein turnover, fused BSC cultures were treated with TBA in the presence or absence of inhibitors for GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R, and resultant protein synthesis and degradation rates were analyzed. Assays were replicated at least 9 times for each inhibitor experiment utilizing BSC cultures obtained from at least 3 different steers that had no previous exposure to steroid compounds. As expected, fused BSC cultures treated with 10 n TBA exhibited increased ( BSC cultures with 10 n TBA in the presence of inhibitors for GPCR, MMP2/9, hbEGF, EGFR, erbB2, or IGF-1R suppressed ( 0.05) effect on TBA-mediated decreases in protein degradation. However, inhibition of both EGFR and erbB2 in the presence of 10 n TBA resulted in decreased ( BSC cultures treated with 10 n TBA exhibit increased ( BSC cultures.

  9. M-cadherin-mediated intercellular interactions activate satellite cell division.

    Science.gov (United States)

    Marti, Merce; Montserrat, Núria; Pardo, Cristina; Mulero, Lola; Miquel-Serra, Laia; Rodrigues, Alexandre Miguel Cavaco; Andrés Vaquero, José; Kuebler, Bernd; Morera, Cristina; Barrero, María José; Izpisua Belmonte, Juan Carlos

    2013-11-15

    Adult muscle stem cells and their committed myogenic precursors, commonly referred to as the satellite cell population, are involved in both muscle growth after birth and regeneration after damage. It has been previously proposed that, under these circumstances, satellite cells first become activated, divide and differentiate, and only later fuse to the existing myofiber through M-cadherin-mediated intercellular interactions. Our data show that satellite cells fuse with the myofiber concomitantly to cell division, and only when the nuclei of the daughter cells are inside the myofiber, do they complete the process of differentiation. Here we demonstrate that M-cadherin plays an important role in cell-to-cell recognition and fusion, and is crucial for cell division activation. Treatment of satellite cells with M-cadherin in vitro stimulates cell division, whereas addition of anti-M-cadherin antibodies reduces the cell division rate. Our results suggest an alternative model for the contribution of satellite cells to muscle development, which might be useful in understanding muscle regeneration, as well as muscle-related dystrophies.

  10. Title: Rice Crop Monitoring by Fusing Microwave and Optical Satellite Data

    Science.gov (United States)

    Oyoshi, K.; Takeuchi, W.; LE Toan, T.; Sobue, S.

    2015-12-01

    Rapid population and economic growth, and the increase in extreme weather events, are destabilizing global food security. In Asia, rice is a staple cereal crop, and the continent accounts for about 90% of global rice production and consumption. The Group on Earth Observations (GEO) Global Agricultural Monitoring (GLAM) was launched in 2011 to utilize remote sensing tools to enhance crop production projections in order to promote food security and foster sustainable economic growth. Asia---‒Rice Crop Estimation & Monitoring (Asia---‒RiCE) is a component of GEOGLAM, and aims to use remote sensing tools to develop rice---‒related information such as maps of paddy fields, rice growing conditions, yield, and production. However, in some regions in Southeast Asia, rice is planted and harvested more than twice a year, and the crop calendar is quite complicated. In addition, rice is mainly cultivated in the rainy season, and the high density of cloud cover during that season limits the observations that can be made from space using only optical sensors. In contrast, Synthetic Aperture Radar (SAR) is a robust tool because it penetrates cloud cover; however, the revisit frequency of a single SAR satellite is limited, making it difficult to capture the complicated rice crop calendar in Asia. In this research, time---‒series SAR data were fused with optical data to monitor rice crops in Southeast Asia with complicated crop calendars. In addition, a microwave radiometer that also penetrates clouds and has a high revisit frequency but a coarse spatial resolution (greater than several kilometers), was used. The integrated use of a large variety of satellite data enables us to periodically monitor surface conditions such as water inundation, transplanting, and rice crop growth and harvesting, which in turn enables us to examine rice planted areas, rice crop calendars, and rice growing conditions in order to estimate rice production.

  11. Mapping Urban Tree Canopy Cover Using Fused Airborne LIDAR and Satellite Imagery Data

    Science.gov (United States)

    Parmehr, Ebadat G.; Amati, Marco; Fraser, Clive S.

    2016-06-01

    Urban green spaces, particularly urban trees, play a key role in enhancing the liveability of cities. The availability of accurate and up-to-date maps of tree canopy cover is important for sustainable development of urban green spaces. LiDAR point clouds are widely used for the mapping of buildings and trees, and several LiDAR point cloud classification techniques have been proposed for automatic mapping. However, the effectiveness of point cloud classification techniques for automated tree extraction from LiDAR data can be impacted to the point of failure by the complexity of tree canopy shapes in urban areas. Multispectral imagery, which provides complementary information to LiDAR data, can improve point cloud classification quality. This paper proposes a reliable method for the extraction of tree canopy cover from fused LiDAR point cloud and multispectral satellite imagery data. The proposed method initially associates each LiDAR point with spectral information from the co-registered satellite imagery data. It calculates the normalised difference vegetation index (NDVI) value for each LiDAR point and corrects tree points which have been misclassified as buildings. Then, region growing of tree points, taking the NDVI value into account, is applied. Finally, the LiDAR points classified as tree points are utilised to generate a canopy cover map. The performance of the proposed tree canopy cover mapping method is experimentally evaluated on a data set of airborne LiDAR and WorldView 2 imagery covering a suburb in Melbourne, Australia.

  12. Dendritic cells fused with different pancreatic carcinoma cells induce different T-cell responses

    Directory of Open Access Journals (Sweden)

    Andoh Y

    2013-01-01

    Full Text Available Yoshiaki Andoh,1,2 Naohiko Makino,2 Mitsunori Yamakawa11Department of Pathological Diagnostics, 2Department of Gastroenterology, Yamagata University School of Medicine, Yamagata, JapanBackground: It is unclear whether there are any differences in the induction of cytotoxic T lymphocytes (CTL and CD4+CD25high regulatory T-cells (Tregs among dendritic cells (DCs fused with different pancreatic carcinomas. The aim of this study was to compare the ability to induce cytotoxicity by human DCs fused with different human pancreatic carcinoma cell lines and to elucidate the causes of variable cytotoxicity among cell lines.Methods: Monocyte-derived DCs, which were generated from peripheral blood mononuclear cells (PBMCs, were fused with carcinoma cells such as Panc-1, KP-1NL, QGP-1, and KP-3L. The induction of CTL and Tregs, and cytokine profile of PBMCs stimulated by fused DCs were evaluated.Results: The cytotoxicity against tumor targets induced by PBMCs cocultured with DCs fused with QGP-1 (DC/QGP-1 was very low, even though PBMCs cocultured with DCs fused with other cell lines induced significant cytotoxicity against the respective tumor target. The factors causing this low cytotoxicity were subsequently investigated. DC/QGP-1 induced a significant expansion of Tregs in cocultured PBMCs compared with DC/KP-3L. The level of interleukin-10 secreted in the supernatants of PBMCs cocultured with DC/QGP-1 was increased significantly compared with that in DC/KP-3L. Downregulation of major histocompatibility complex class I expression and increased secretion of vascular endothelial growth factor were observed with QGP-1, as well as in the other cell lines.Conclusion: The present study demonstrated that the cytotoxicity induced by DCs fused with pancreatic cancer cell lines was different between each cell line, and that the reduced cytotoxicity of DC/QGP-1 might be related to the increased secretion of interleukin-10 and the extensive induction of Tregs

  13. Leucocytes, cytokines and satellite cells

    DEFF Research Database (Denmark)

    Paulsen, Gøran; Mikkelsen, Ulla Ramer; Raastad, Truls

    2012-01-01

    -damaging exercise', primarily eccentric exercise. We review the evidence for the notion that the degree of muscle damage is related to the magnitude of the cytokine response. In the third and final section, we look at the satellite cell response to a single bout of eccentric exercise, as well as the role...... damage. With the exception of IL-6, the sources of systemic cytokines following exercise remain unclear The satellite cell response to severe muscle damage is related to regeneration, whereas the biological significance of satellite cell proliferation after mild damage or non-damaging exercise remains...

  14. Muscle Satellite Cells: Exploring the Basic Biology to Rule Them.

    Science.gov (United States)

    Almeida, Camila F; Fernandes, Stephanie A; Ribeiro Junior, Antonio F; Keith Okamoto, Oswaldo; Vainzof, Mariz

    2016-01-01

    Adult skeletal muscle is a postmitotic tissue with an enormous capacity to regenerate upon injury. This is accomplished by resident stem cells, named satellite cells, which were identified more than 50 years ago. Since their discovery, many researchers have been concentrating efforts to answer questions about their origin and role in muscle development, the way they contribute to muscle regeneration, and their potential to cell-based therapies. Satellite cells are maintained in a quiescent state and upon requirement are activated, proliferating, and fusing with other cells to form or repair myofibers. In addition, they are able to self-renew and replenish the stem pool. Every phase of satellite cell activity is highly regulated and orchestrated by many molecules and signaling pathways; the elucidation of players and mechanisms involved in satellite cell biology is of extreme importance, being the first step to expose the crucial points that could be modulated to extract the optimal response from these cells in therapeutic strategies. Here, we review the basic aspects about satellite cells biology and briefly discuss recent findings about therapeutic attempts, trying to raise questions about how basic biology could provide a solid scaffold to more successful use of these cells in clinics.

  15. Satellite cells: the architects of skeletal muscle.

    Science.gov (United States)

    Chang, Natasha C; Rudnicki, Michael A

    2014-01-01

    The outstanding regenerative capacity of skeletal muscle is attributed to the resident muscle stem cell termed satellite cell. Satellite cells are essential for skeletal muscle regeneration as they ultimately provide the myogenic precursors that rebuild damaged muscle tissue. Satellite cells characteristically are a heterogeneous population of stem cells and committed progenitor cells. Delineation of cellular hierarchy and understanding how lineage fate choices are determined within the satellite cell population will be invaluable for the advancement of muscle regenerative therapies.

  16. A quinoxaline-fused tetrathiafulvalene-based sensitizer for efficient dye-sensitized solar cells.

    Science.gov (United States)

    Amacher, Anneliese; Yi, Chenyi; Yang, Jiabao; Bircher, Martin Peter; Fu, Yongchun; Cascella, Michele; Grätzel, Michael; Decurtins, Silvio; Liu, Shi-Xia

    2014-06-21

    A new quinoxaline-fused tetrathiafulvalene-based sensitizer has been prepared and characterized. The resulting power conversion efficiency of 6.47% represents the best performance to date for tetrathiafulvalene-sensitized solar cells.

  17. Electro-Deformation of Fused Cells in a Microfluidic Array Device

    Directory of Open Access Journals (Sweden)

    Yan Liu

    2016-11-01

    Full Text Available We present a new method of analyzing the deformability of fused cells in a microfluidic array device. Electrical stresses—generated by applying voltages (4–20 V across discrete co-planar microelectrodes along the side walls of a microfluidic channel—have been used to electro-deform fused and unfused stem cells. Under an electro-deformation force induced by applying an alternating current (AC signal, we observed significant electro-deformation phenomena. The experimental results show that the fused stem cells were stiffer than the unfused stem cells at a relatively low voltage (<16 V. However, at a relatively high voltage, the fused stem cells were more easily deformed than were the unfused stem cells. In addition, the electro-deformation process is modeled based on the Maxwell stress tensor and structural mechanics of cells. The theoretical results show that a positive correlation is found between the deformation of the cell and the applied voltage, which is consistent with the experimental results. Combined with a numerical analysis and experimental study, the results showed that the significant difference of the deformation ratio of the fused and unfused cells is not due to their size difference. This demonstrates that some other properties of cell membranes (such as the membrane structure were also changed in the electrofusion process, in addition to the size modification of that process.

  18. Satellite cells in human skeletal muscle plasticity.

    Science.gov (United States)

    Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

    2015-01-01

    Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  19. Modeling the Effects of the Urban Built-Up Environment on Plant Phenology Using Fused Satellite Data

    Directory of Open Access Journals (Sweden)

    Norman Gervais

    2017-01-01

    Full Text Available Understanding the effects that the Urban Heat Island (UHI has on plant phenology is important in predicting ecological impacts of expanding cities and the impacts of the projected global warming. However, the underlying methods to monitor phenological events often limit this understanding. Generally, one can either have a small sample of in situ measurements or use satellite data to observe large areas of land surface phenology (LSP. In the latter, a tradeoff exists among platforms with some allowing better temporal resolution to pick up discrete events and others possessing the spatial resolution appropriate for observing heterogeneous landscapes, such as urban areas. To overcome these limitations, we applied the Spatial and Temporal Adaptive Reflectance Model (STARFM to fuse Landsat surface reflectance and MODIS nadir BRDF-adjusted reflectance (NBAR data with three separate selection conditions for input data across two versions of the software. From the fused images, we derived a time-series of high temporal and high spatial resolution synthetic Normalized Difference Vegetation Index (NDVI imagery to identify the dates of the start of the growing season (SOS, end of the season (EOS, and the length of the season (LOS. The results were compared between the urban and exurban developed areas within the vicinity of Ogden, UT and across all three data scenarios. The results generally show an earlier urban SOS, later urban EOS, and longer urban LOS, with variation across the results suggesting that phenological parameters are sensitive to input changes. Although there was strong evidence that STARFM has the potential to produce images capable of capturing the UHI effect on phenology, we recommend that future work refine the proposed methods and compare the results against ground events.

  20. Phosphatidic acid phosphatase and phospholipdase A activities in plasma membranes from fusing muscle cells.

    Science.gov (United States)

    Kent, C; Vagelos, P R

    1976-06-17

    Plasma membrane from fusing embryonic muscle cells were assayed for phospholipase A activity to determine if this enzyme plays a role in cell fusion. The membranes were assayed under a variety of conditions with phosphatidylcholine as the substrate and no phospholipase A activity was found. The plasma membranes did contain a phosphatidic acid phosphatase which was optimally active in the presence of Triton X-100 and glycerol. The enzyme activity was constant from pH 5.2 to 7.0, and did not require divalent cations. Over 97% of the phosphatidic acid phosphatase activity was in the particulate fraction. The subcellular distribution of the phosphatidic acid phosphatase was the same as the distributions of the plasma membrane markers, (Na+ + k+)-ATPase and the acetylcholine receptor, which indicates that this phosphatase is located exclusively in the plasma membranes. There was no detectable difference in the phosphatidic acid phosphatase activities of plasma membranes from fusing and non-fusing cells.

  1. Physiological and morphological studies of rat pheochromocytoma cells (PC12) chemically fused and grown in culture.

    OpenAIRE

    O'Lague, P. H.; Huttner, S L

    1980-01-01

    Cell fusion induced by polyethylene glycol has been used to produce in culture giant multinucleate PC12 cells (up to 300 micron in diameter compared to 10-20 micron for unfused cells). Fused cells, like their unfused counterparts, were found to express various neuronal properties. They contained catecholamines. In the presence of nerve growth factor they extended long processes and expressed Na+, Ca2+, and K+ conductances generally associated with excitable cells. In the absence of nerve grow...

  2. Smurfs have "fused" into the asymmetric division of stem cells

    Institute of Scientific and Technical Information of China (English)

    Steven Y. Cheng; Ying E. Zhang

    2011-01-01

    @@ The asymmetric cell division is the way in which a stem cell divides into one daughter stem cell and one differentiated daughter cell.This process is one of the key principles of developmental biology that ensures the perpetual supply of stem cells while allowing a particular cell lineage to be populated.During Drosophila oogenesis, the fate of the daughter stem cell produced from the asymmetric division of germline stem cells (GSCs) is specified by Decapentaplegic (Dpp), but the other daughter cell has almost equal access to the Dpp signal.

  3. Chlorotoxin Fused to IgG-Fc Inhibits Glioblastoma Cell Motility via Receptor-Mediated Endocytosis

    Directory of Open Access Journals (Sweden)

    Tomonari Kasai

    2012-01-01

    Full Text Available Chlorotoxin is a 36-amino acid peptide derived from Leiurus quinquestriatus (scorpion venom, which has been shown to inhibit low-conductance chloride channels in colonic epithelial cells. Chlorotoxin also binds to matrix metalloproteinase-2 and other proteins on glioma cell surfaces. Glioma cells are considered to require the activation of matrix metalloproteinase-2 during invasion and migration. In this study, for targeting glioma, we designed two types of recombinant chlorotoxin fused to human IgG-Fcs with/without a hinge region. Chlorotoxin fused to IgG-Fcs was designed as a dimer of 60 kDa with a hinge region and a monomer of 30 kDa without a hinge region. The monomeric and dimeric forms of chlorotoxin inhibited cell proliferation at 300 nM and induced internalization in human glioma A172 cells. The monomer had a greater inhibitory effect than the dimer; therefore, monomeric chlorotoxin fused to IgG-Fc was multivalently displayed on the surface of bionanocapsules to develop a drug delivery system that targeted matrix metalloproteinase-2. The target-dependent internalization of bionanocapsules in A172 cells was observed when chlorotoxin was displayed on the bionanocapsules. This study indicates that chlorotoxin fused to IgG-Fcs could be useful for the active targeting of glioblastoma cells.

  4. Fused-Thiophene Based Materials for Organic Photovoltaics and Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Prabakaran Kumaresan

    2014-10-01

    Full Text Available Organic photovoltaics (OPVs and dye-sensitized solar cells (DSSCs have drawn great interest from both academics and industry, due to the possibility of low-cost conversion of photovoltaic energy at reasonable efficiencies. This review focuses on recent progress in molecular engineering and technological aspects of fused-thiophene-based organic dye molecules for applications in solar cells. Particular attention has been paid to the design principles and stability of these dye molecules, as well as on the effects of various electrolyte systems for DSSCs. Importantly, it has been found that incorporation of a fused-thiophene unit into the sensitizer has several advantages, such as red-shift of the intramolecular charge transfer band, tuning of the frontier molecular energy level, and improvements in both photovoltaic performance and stability. This work also examines the correlation between the physical properties and placement of fused-thiophene in the molecular structure with regard to their performance in OPVs and DSSCs.

  5. Physiological and morphological studies of rat pheochromocytoma cells (PC12) chemically fused and grown in culture.

    Science.gov (United States)

    O'Lague, P H; Huttner, S L

    1980-03-01

    Cell fusion induced by polyethylene glycol has been used to produce in culture giant multinucleate PC12 cells (up to 300 micron in diameter compared to 10-20 micron for unfused cells). Fused cells, like their unfused counterparts, were found to express various neuronal properties. They contained catecholamines. In the presence of nerve growth factor they extended long processes and expressed Na+, Ca2+, and K+ conductances generally associated with excitable cells. In the absence of nerve growth factor these cells neither grew long processes nor generated Na+-spikes. Other neuronal properties were also observed.

  6. PRMT7 Preserves Satellite Cell Regenerative Capacity.

    Science.gov (United States)

    Blanc, Roméo Sébastien; Vogel, Gillian; Chen, Taiping; Crist, Colin; Richard, Stéphane

    2016-02-16

    Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells), which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7(-/-) adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

  7. PRMT7 Preserves Satellite Cell Regenerative Capacity

    Directory of Open Access Journals (Sweden)

    Roméo Sébastien Blanc

    2016-02-01

    Full Text Available Regeneration of skeletal muscle requires the continued presence of quiescent muscle stem cells (satellite cells, which become activated in response to injury. Here, we report that whole-body protein arginine methyltransferase PRMT7−/− adult mice and mice conditionally lacking PRMT7 in satellite cells using Pax7-CreERT2 both display a significant reduction in satellite cell function, leading to defects in regenerative capacity upon muscle injury. We show that PRMT7 is preferentially expressed in activated satellite cells and, interestingly, PRMT7-deficient satellite cells undergo cell-cycle arrest and premature cellular senescence. These defects underlie poor satellite cell stem cell capacity to regenerate muscle and self-renew after injury. PRMT7-deficient satellite cells express elevated levels of the CDK inhibitor p21CIP1 and low levels of its repressor, DNMT3b. Restoration of DNMT3b in PRMT7-deficient cells rescues PRMT7-mediated senescence. Our findings define PRMT7 as a regulator of the DNMT3b/p21 axis required to maintain muscle stem cell regenerative capacity.

  8. Regulation of satellite cell function in sarcopenia

    Directory of Open Access Journals (Sweden)

    Stephen E Alway

    2014-09-01

    Full Text Available The mechanisms contributing to sarcopenia include reduced satellite cell (myogenic stem cell function that is impacted by the environment (niche of these cells. Satellite cell function is affected by oxidative stress, which is elevated in aged muscles, and this along with changes in largely unknown systemic factors, likely contribute to the manner in which satellite cells respond to stressors such as exercise, disuse or rehabilitation in sarcopenic muscles. Nutritional intervention provides one therapeutic strategy to improve the satellite cell niche and systemic factors, with the goal of improving satellite cell function in aging muscles. Although many elderly persons consume various nutraceuticals with the hope of improving health, most of these compounds have not been thoroughly tested, and the impacts that they might have on sarcopenia, and satellite cell function are not clear. This review discusses data pertaining to the satellite cell responses and function in aging skeletal muscle, and the impact that three compounds: resveratrol, green tea catechins and β-Hydroxy-β-methylbutyrate have on regulating satellite cell function and therefore contributing to reducing sarcopenia or improving muscle mass after disuse in aging. The data suggest that these nutraceutical compounds improve satellite cell function during rehabilitative loading in animal models of aging after disuse (i.e., muscle regeneration. While these compounds have not been rigorously tested in humans, the data from animal models of aging provide a strong basis for conducting additional focused work to determine if these or other nutraceuticals can offset the muscle losses, or improve regeneration in sarcopenic muscles of older humans via improving satellite cell function.

  9. Perylene anhydride fused porphyrins as near-infrared sensitizers for dye-sensitized solar cells

    KAUST Repository

    Jiao, Chongjun

    2011-07-15

    Two perylene anhydride fused porphyrins 1 and 2 have been synthesized and employed successfully in dye-sensitized solar cells (DSCs). Both compounds showed broad incident monochromatic photon-to-current conversion efficiency spectra covering the entire visible spectral region and even extending into the near-infrared (NIR) region up to 1000 nm, which is impressive for ruthenium-free dyes in DSCs. © 2011 American Chemical Society.

  10. A 4% efficient organic solar cell using a fluorinated fused subphthalocyanine dimer as an electron acceptor

    Energy Technology Data Exchange (ETDEWEB)

    Verreet, Bregt; Heremans, Paul [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); ESAT, Katholieke Universiteit Leuven, Kasteelpark Arenberg 10, B-3001 Leuven (Belgium); Rand, Barry P.; Cheyns, David; Hadipour, Afshin; Aernouts, Tom [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Medina, Anais; Claessens, Christian G. [Departamento de Quimica Organica, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); Torres, Tomas [Departamento de Quimica Organica, Universidad Autonoma de Madrid, Cantoblanco, 28049 Madrid (Spain); IMDEA-Nanociencia, Facultad de Ciencias, Ciudad Universitaria de Cantoblanco, 28049 Madrid (Spain)

    2011-07-15

    Planar bilayer organic solar cells with a fluorinated fused subphthalocyanine dimer (FSubPcDimer) as an acceptor and chloroboron (III) subphthalocyanine (SubPc) as a donor obtain a 60% higher J{sub sc} compared to cells using C{sub 60} as an acceptor, resulting in a power conversion efficiency of 4%. This is obtained thanks to the important contribution to the photocurrent of the low-bandgap FSubPcDimer. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  11. A panchromatic anthracene-fused porphyrin sensitizer for dye-sensitized solar cells

    KAUST Repository

    Ball, James M.

    2012-01-01

    The development of ruthenium-free sensitizers which absorb light over a broad range of the solar spectrum is important for improving the power conversion efficiency of dye-sensitized solar cells. Here we study three chemically tailored porphyrin-based dyes. We show that by fusing the porphyrin core to an anthracene unit, we can extend the conjugation length and lower the optical gap, shifting the absorption spectrum into the near-infrared (NIR). All three dyes were tested in dye-sensitized solar cells, using both titanium dioxide and tin dioxide as the electron-transport material. Solar cells incorporating the anthracene-fused porphyrin dye exhibit photocurrent collection at wavelengths up to about 1100 nm, which is the longest reported for a porphyrin-based system. Despite extending the photon absorption bandwidth, device efficiency is found to be low, which is a common property of cells based on porphyrin dyes with NIR absorption. We show that in the present case the efficiency is reduced by inefficient electron injection into the oxide, as opposed to dye regeneration, and highlight some important design considerations for panchromatic sensitizers. © 2012 The Royal Society of Chemistry.

  12. Spatial distribution and temporal evolution of DRONPA-fused SNAP25 clusters in adrenal chromaffin cells

    DEFF Research Database (Denmark)

    Antoku, Yasuko; Dedecker, Peter; da Silva Pinheiro, Paulo César;

    2015-01-01

    Sub-diffraction imaging of plasma membrane localized proteins, such as the SNARE (Soluble NSF Attachment Protein Receptor) proteins involved in exocytosis, in fixed cells have resulted in images with high spatial resolution, at the expense of dynamical information. Here, we have imaged localized......, making possible the simultaneous identification of cluster size, location and temporal evolution. The results indicate that the DRONPA-fused SNAP-25 clusters display rich dynamics, going from staying constant to disappearing and reappearing in specific cluster domains within minutes....

  13. Spatial distribution and temporal evolution of DRONPA-fused SNAP25 clusters in adrenal chromaffin cells

    DEFF Research Database (Denmark)

    Antoku, Yasuko; Dedecker, Peter; da Silva Pinheiro, Paulo César

    2015-01-01

    Sub-diffraction imaging of plasma membrane localized proteins, such as the SNARE (Soluble NSF Attachment Protein Receptor) proteins involved in exocytosis, in fixed cells have resulted in images with high spatial resolution, at the expense of dynamical information. Here, we have imaged localized ......, making possible the simultaneous identification of cluster size, location and temporal evolution. The results indicate that the DRONPA-fused SNAP-25 clusters display rich dynamics, going from staying constant to disappearing and reappearing in specific cluster domains within minutes....

  14. Fused Zirconia

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    ScopeThis standard specifies the terms,definitions,classification,brands,technical requirements,test methods,inspection rules,packing,marking,transportation,storage,and quality certificate of fused zirconia.This standard is applicable to monoclinic fused zirconia and partially stabilized fused zirconia.

  15. Primordial germ cell proliferation is impaired in Fused Toes mutant embryos.

    Science.gov (United States)

    Kim, Bongki; Kim, Youngha; Sakuma, Rui; Hui, Chi-Chung; Rüther, Ulrich; Jorgensen, Joan S

    2011-01-15

    Over the first 4 days of their life, primordial germ cells invade the endoderm, migrate into and through the developing hindgut, and traverse to the genital ridge where they cluster and ultimately inhabit the nascent gonad. Specific signal-receptor combinations between primordial germ cells and their immediate environment establish successful migration and colonization. Here we demonstrate that disruption of a cluster of six genes on murine chromosome 8, as exemplified by the Fused Toes (Ft) mutant mouse model, results in severely decreased numbers of primordial germ cells within the early gonad. Primordial germ cell migration appeared normal within Ft mutant embryos; however, germ cell counts progressively decreased during this time. Although no difference in apoptosis was detected, we report a critical decrease in primordial germ cell proliferation by E12.5. The six genes within the Ft locus include the IrxB cluster (Irx3, -5, -6), Fts, Ftm, and Fto, of which only Ftm, Fto, and Fts are expressed in primordial germ cells of the early gonad. From these studies, we have discovered that the Ft locus on mouse chromosome 8 is associated with cell cycle deficits within the primordial germ cell population that initiates just before translocation into the genital ridge. Copyright © 2010 Elsevier Inc. All rights reserved.

  16. Muscle Satellite Cell Heterogeneity and Self-Renewal

    Directory of Open Access Journals (Sweden)

    Norio eMotohashi

    2014-01-01

    Full Text Available Adult skeletal muscle possesses extraordinary regeneration capacities. After muscle injury or exercise, large numbers of newly formed muscle fibers are generated within a week as a result of expansion and differentiation of a self-renewing pool of muscle stem cells termed muscle satellite cells. Normally, satellite cells are mitotically quiescent and reside beneath the basal lamina of muscle fibers. Upon regeneration, satellite cells are activated, and give rise to daughter myogenic precursor cells. After several rounds of proliferation, these myogenic precursor cells contribute to the formation of new muscle fibers. During cell division, a minor population of myogenic precursor cells returns to quiescent satellite cells as a self-renewal process. Currently, accumulating evidence has revealed the essential roles of satellite cells in muscle regeneration and the regulatory mechanisms, while it still remains to be elucidated how satellite cell self-renewal is molecularly regulated and how satellite cells are important in aging and diseased muscle. The number of satellite cells is decreased due to the changing niche during ageing, resulting in attenuation of muscle regeneration capacity. Additionally, in Duchenne muscular dystrophy (DMD patients, the loss of satellite cell regenerative capacity and decreased satellite cell number due to continuous needs for satellite cells lead to progressive muscle weakness with chronic degeneration. Thus, it is necessary to replenish muscle satellite cells continuously. This review outlines recent findings regarding satellite cell heterogeneity, asymmetric division and molecular mechanisms in satellite cell self-renewal which is crucial for maintenance of satellite cells as a muscle stem cell pool throughout life. In addition, we discuss roles in the stem cell niche for satellite cell maintenance, as well as related cell therapies for approaching treatment of DMD.

  17. Sox10 directs neural stem cells toward the oligodendrocyte lineage by decreasing Suppressor of Fused expression

    Science.gov (United States)

    Pozniak, Christine D.; Langseth, Abraham J.; Dijkgraaf, Gerrit J. P.; Choe, Youngshik; Werb, Zena; Pleasure, Samuel J.

    2010-01-01

    Oligodendrocyte precursor cells (OPCs) are lineage-restricted progenitors generally limited in vivo to producing oligodendrocytes. Mechanisms controlling genesis of OPCs are of interest because of their importance in myelin development and their potential for regenerative therapies in multiple sclerosis and dysmyelinating syndromes. We show here that the SoxE transcription factors (comprising Sox8, 9, and 10) induce multipotent neural precursor cells (NPCs) from the early postnatal subventricular zone (SVZ) to become OPCs in an autonomous manner. We performed a chromatin immunoprecipitation-based bioinformatic screen and identified Suppressor of Fused (Sufu) as a direct target of repression by Sox10. In vitro, overexpression of Sufu blocked OPC production, whereas RNAi-mediated inhibition augmented OPC production. Furthermore, mice heterozygous for Sufu have increased numbers of OPCs in the telencephalon during development. We conclude that Sox10 acts to restrict the potential of NPCs toward the oligodendrocyte lineage in part by regulating the expression of Sufu. PMID:21098272

  18. Skeletal Muscle Satellite Cell Activation Following Cutaneous Burn in Rats

    Science.gov (United States)

    2013-12-01

    Satellite cell isolation and culture Satellite cells were isolated similar as described by Allen et al. [30]. Following euthanasia , muscles were...satellite cell cultures. Methods Cell Biol 1997;52:155–76. [31] Tatsumi R, Liu X, Pulido A, Morales M, Sakata T, Dial S, Hattori A, Ikeuchi Y, Allen RE

  19. Isolation and Culture of Satellite Cells from Mouse Skeletal Muscle.

    Science.gov (United States)

    Musarò, Antonio; Carosio, Silvia

    2017-01-01

    Skeletal muscle tissue is characterized by a population of quiescent mononucleated myoblasts, localized between the basal lamina and sarcolemma of myofibers, known as satellite cells. Satellite cells play a pivotal role in muscle homeostasis and are the major source of myogenic precursors in mammalian muscle regeneration.This chapter describes protocols for isolation and culturing satellite cells isolated from mouse skeletal muscles. The classical procedure, which will be discussed extensively in this chapter, involves the enzymatic dissociation of skeletal muscles, while the alternative method involves isolation of satellite cells from isolated myofibers in which the satellite cells remain in their in situ position underneath the myofiber basal lamina.In particular, we discuss the technical aspect of satellite cell isolation, the methods necessary to enrich the satellite cell fraction and the culture conditions that optimize proliferation and myotube formation of mouse satellite cells.

  20. BMP signaling regulates satellite cell-dependent postnatal muscle growth.

    Science.gov (United States)

    Stantzou, Amalia; Schirwis, Elija; Swist, Sandra; Alonso-Martin, Sonia; Polydorou, Ioanna; Zarrouki, Faouzi; Mouisel, Etienne; Beley, Cyriaque; Julien, Anaïs; Le Grand, Fabien; Garcia, Luis; Colnot, Céline; Birchmeier, Carmen; Braun, Thomas; Schuelke, Markus; Relaix, Frédéric; Amthor, Helge

    2017-08-01

    Postnatal growth of skeletal muscle largely depends on the expansion and differentiation of resident stem cells, the so-called satellite cells. Here, we demonstrate that postnatal satellite cells express components of the bone morphogenetic protein (BMP) signaling machinery. Overexpression of noggin in postnatal mice (to antagonize BMP ligands), satellite cell-specific knockout of Alk3 (the gene encoding the BMP transmembrane receptor) or overexpression of inhibitory SMAD6 decreased satellite cell proliferation and accretion during myofiber growth, and ultimately retarded muscle growth. Moreover, reduced BMP signaling diminished the adult satellite cell pool. Abrogation of BMP signaling in satellite cell-derived primary myoblasts strongly diminished cell proliferation and upregulated the expression of cell cycle inhibitors p21 and p57 In conclusion, these results show that BMP signaling defines postnatal muscle development by regulating satellite cell-dependent myofiber growth and the generation of the adult muscle stem cell pool. © 2017. Published by The Company of Biologists Ltd.

  1. Proliferation conditions for human satellite cells. The fractional content of satellite cells

    DEFF Research Database (Denmark)

    Gaster, M; Beck-Nielsen, H; Schrøder, H D

    2001-01-01

    the fraction of Sc in culture. Evaluation of different culture conditions allowed us to find proliferation conditions preferentially for Sc: a) Sc should be cultured on surfaces coated with ECM-gel. b) Primary cell culture should be inoculated in DMEM supplemented with 10% fetal calf serum to increase cell......Primary satellite cell cultures have become an important tool as a model system for skeletal muscles. A common problem in human satellite cell culturing is fibroblast overgrowth. We combined N-CAM (Leu19) immunocytochemical staining of satellite cells (Sc) with stereological methods to estimate...... adherence. c) Change of media to DMEM supplemented with 2% Ultroser-G and 2% FCS after 24 h.d) Before subcultivation, cells should be preplated for 30 min. The fractional content of Sc in passage four when applying this method of cultivation was 0.82 +/- 0.07 (mean +/- SE, N = 10). Our method enabled us...

  2. Non-fullerene acceptors containing fluoranthene-fused imides for solution-processed inverted organic solar cells.

    Science.gov (United States)

    Zhou, Yan; Dai, Ya-Zhong; Zheng, Yu-Qing; Wang, Xiao-Ye; Wang, Jie-Yu; Pei, Jian

    2013-06-28

    Six fluoranthene-fused imide derivatives were employed as acceptors in solution processed inverted BHJ solar cells with P3HT as the donor. The PCEs of all devices vary from 2.14% to 2.89%. All acceptors are in their amorphous state with low electron mobility, but achieving high PCEs.

  3. Fusing Mobile In Situ Observations and Satellite Remote Sensing of Chemical Release Emissions to Improve Disaster Response

    Directory of Open Access Journals (Sweden)

    Ira Leifer

    2016-09-01

    Full Text Available Chemical release disasters have serious consequences, disrupting ecosystems, society, and causing significant loss of life. Mitigating the destructive impacts relies on identification and mapping, monitoring, and trajectory forecasting. Improvements in sensor capabilities are enabling airborne and spacebased remote sensing to support response activities. Key applications are improving transport models in complex terrain and improved disaster response.Chemical release disasters have serious consequences, disrupting ecosystems, society, and causing significant loss of life. Mitigating the destructive impacts relies on identification and mapping, monitoring, and trajectory forecasting. Improvements in sensor capabilities are enabling airborne and space-based remote sensing to support response activities. Key applications are improving transport models in complex terrain and improved disaster response.Understanding urban atmospheric transport in the Los Angeles Basin, where topographic influences on transport patterns are significant, was improved by leveraging the Aliso Canyon leak as an atmospheric tracer. Plume characterization data was collected by the AutoMObile trace Gas (AMOG Surveyor, a commuter car modified for science. Mobile surface in situ CH4 and winds were measured by AMOG Surveyor under Santa Ana conditions to estimate an emission rate of 365±30% Gg yr-1. Vertical profiles were collected by AMOG Surveyor by leveraging local topography for vertical profiling to identify the planetary boundary layer at ~700 m. Topography significantly constrained plume dispersion by up to a factor of two. The observed plume trajectory was used to validate satellite aerosol optical depth-inferred atmospheric transport, which suggested the plume first was driven offshore, but then veered back towards land. Numerical long-range transport model predictions confirm this interpretation. This study demonstrated a novel application of satellite aerosol remote

  4. Satellite Cells in Muscular Dystrophy - Lost in Polarity.

    Science.gov (United States)

    Chang, Natasha C; Chevalier, Fabien P; Rudnicki, Michael A

    2016-06-01

    Recent findings employing the mdx mouse model for Duchenne muscular dystrophy (DMD) have revealed that muscle satellite stem cells play a direct role in contributing to disease etiology and progression of DMD, the most common and severe form of muscular dystrophy. Lack of dystrophin expression in DMD has critical consequences in satellite cells including an inability to establish cell polarity, abrogation of asymmetric satellite stem-cell divisions, and failure to enter the myogenic program. Thus, muscle wasting in dystrophic mice is not only caused by myofiber fragility but is exacerbated by intrinsic satellite cell dysfunction leading to impaired regeneration. Despite intense research and clinical efforts, there is still no effective cure for DMD. In this review we highlight recent research advances in DMD and discuss the current state of treatment and, importantly, how we can incorporate satellite cell-targeted therapeutic strategies to correct satellite cell dysfunction in DMD.

  5. Myogenic skeletal muscle satellite cells communicate by tunnelling nanotubes.

    Science.gov (United States)

    Tavi, Pasi; Korhonen, Topi; Hänninen, Sandra L; Bruton, Joseph D; Lööf, Sara; Simon, Andras; Westerblad, Håkan

    2010-05-01

    Quiescent satellite cells sit on the surface of the muscle fibres under the basal lamina and are activated by a variety of stimuli to disengage, divide and differentiate into myoblasts that can regenerate or repair muscle fibres. Satellite cells adopt their parent's fibre type and must have some means of communication with the parent fibre. The mechanisms behind this communication are not known. We show here that satellite cells form dynamic connections with muscle fibres and other satellite cells by F-actin based tunnelling nanotubes (TNTs). Our results show that TNTs readily develop between satellite cells and muscle fibres. Once developed, TNTs permit transport of intracellular material, and even cellular organelles such as mitochondria between the muscle fibre and satellite cells. The onset of satellite cell differentiation markers Pax-7 and MyoD expression was slower in satellite cells cultured in the absence than in the presence of muscle cells. Furthermore physical contact between myofibre and satellite cell progeny is required to maintain subtype identity. Our data establish that TNTs constitute an integral part of myogenic cell communication and that physical cellular interaction control myogenic cell fate determination.

  6. Functional Overload Enhances Satellite Cell Properties in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Shin Fujimaki

    2016-01-01

    Full Text Available Skeletal muscle represents a plentiful and accessible source of adult stem cells. Skeletal-muscle-derived stem cells, termed satellite cells, play essential roles in postnatal growth, maintenance, repair, and regeneration of skeletal muscle. Although it is well known that the number of satellite cells increases following physical exercise, functional alterations in satellite cells such as proliferative capacity and differentiation efficiency following exercise and their molecular mechanisms remain unclear. Here, we found that functional overload, which is widely used to model resistance exercise, causes skeletal muscle hypertrophy and converts satellite cells from quiescent state to activated state. Our analysis showed that functional overload induces the expression of MyoD in satellite cells and enhances the proliferative capacity and differentiation potential of these cells. The changes in satellite cell properties coincided with the inactivation of Notch signaling and the activation of Wnt signaling and likely involve modulation by transcription factors of the Sox family. These results indicate the effects of resistance exercise on the regulation of satellite cells and provide insight into the molecular mechanism of satellite cell activation following physical exercise.

  7. Isolation, Culture and Identification of Porcine Skeletal Muscle Satellite Cells

    Directory of Open Access Journals (Sweden)

    Bo-jiang Li

    2015-08-01

    Full Text Available The objective of this study was to establish the optimum protocol for the isolation and culture of porcine muscle satellite cells. Mononuclear muscle satellite cells are a kind of adult stem cell, which is located between the basal lamina and sarcolemma of muscle fibers and is the primary source of myogenic precursor cells in postnatal muscle. Muscle satellite cells are a useful model to investigate the mechanisms of muscle growth and development. Although the isolation and culture protocols of muscle satellite cells in some species (e.g. mouse have been established successfully, the culture system for porcine muscle satellite cells is very limited. In this study, we optimized the isolation procedure of porcine muscle satellite cells and elaborated the isolation and culture process in detail. Furthermore, we characterized the porcine muscle satellite cells using the immunofluorecence. Our study provides a reference for the isolation of porcine muscle satellite cells and will be useful for studying the molecular mechanisms in these cells.

  8. Satellite cells from dystrophic muscle retain regenerative capacity

    Directory of Open Access Journals (Sweden)

    Luisa Boldrin

    2015-01-01

    Full Text Available Duchenne muscular dystrophy is an inherited disorder that is characterized by progressive skeletal muscle weakness and wasting, with a failure of muscle maintenance/repair mediated by satellite cells (muscle stem cells. The function of skeletal muscle stem cells resident in dystrophic muscle may be perturbed by being in an increasing pathogenic environment, coupled with constant demands for repairing muscle. To investigate the contribution of satellite cell exhaustion to this process, we tested the functionality of satellite cells isolated from the mdx mouse model of Duchenne muscular dystrophy. We found that satellite cells derived from young mdx mice contributed efficiently to muscle regeneration within our in vivo mouse model. To then test the effects of long-term residence in a dystrophic environment, satellite cells were isolated from aged mdx muscle. Surprisingly, they were as functional as those derived from young or aged wild type donors. Removing satellite cells from a dystrophic milieu reveals that their regenerative capacity remains both intact and similar to satellite cells derived from healthy muscle, indicating that the host environment is critical for controlling satellite cell function.

  9. The role of satellite cells in muscle hypertrophy.

    Science.gov (United States)

    Blaauw, Bert; Reggiani, Carlo

    2014-02-01

    The role of satellite cells in muscle hypertrophy has long been a debated issue. In the late 1980s it was shown that proteins remain close to the myonucleus responsible for its synthesis, giving rise to the idea of a nuclear domain. This, together with the observation that during various models of muscle hypertrophy there is an activation of the muscle stem cells, i.e. satellite cells, lead to the idea that satellite cell activation is required for muscle hypertrophy. Thus, satellite cells are not only responsible for muscle repair and regeneration, but also for hypertrophic growth. Further support for this line of thinking was obtained after studies showing that irradiation of skeletal muscle, and therefore elimination of all satellite cells, completely prevented overload-induced hypertrophy. Recently however, using different transgenic approaches, it has become clear that muscle hypertrophy can occur without a contribution of satellite cells, even though in most situations of muscle hypertrophy satellite cells are activated. In this review we will discuss the contribution of satellite cells, and other muscle-resident stem cells, to muscle hypertrophy both in mice as well as in humans.

  10. Ectopic development of skeletal muscle induced by subcutaneous transplant of rat satellite cells

    Directory of Open Access Journals (Sweden)

    M.G. Fukushima

    2005-03-01

    Full Text Available The present study analyzes the ectopic development of the rat skeletal muscle originated from transplanted satellite cells. Satellite cells (10(6 cells obtained from hindlimb muscles of newborn female 2BAW Wistar rats were injected subcutaneously into the dorsal area of adult male rats. After 3, 7, and 14 days, the transplanted tissues (N = 4-5 were processed for histochemical analysis of peripheral nerves, inactive X-chromosome and acetylcholinesterase. Nicotinic acetylcholine receptors (nAChRs were also labeled with tetramethylrhodamine-labeled alpha-bungarotoxin. The development of ectopic muscles was successful in 86% of the implantation sites. By day 3, the transplanted cells were organized as multinucleated fibers containing multiple clusters of nAChRs (N = 2-4, resembling those from non-innervated cultured skeletal muscle fibers. After 7 days, the transplanted cells appeared as a highly vascularized tissue formed by bundles of fibers containing peripheral nuclei. The presence of X chromatin body indicated that subcutaneously developed fibers originated from female donor satellite cells. Differently from the extensor digitorum longus muscle of adult male rat (87.9 ± 1.0 µm; N = 213, the diameter of ectopic fibers (59.1 µm; N = 213 did not obey a Gaussian distribution and had a higher coefficient of variation. After 7 and 14 days, the organization of the nAChR clusters was similar to that of clusters from adult innervated extensor digitorum longus muscle. These findings indicate the histocompatibility of rats from 2BAW colony and that satellite cells transplanted into the subcutaneous space of adult animals are able to develop and fuse to form differentiated skeletal muscle fibers.

  11. A global downregulation of microRNAs occurs in human quiescent satellite cells during myogenesis

    NARCIS (Netherlands)

    Koning, Merel; Werker, Paul M N; van Luyn, Marja J A; Krenning, Guido; Harmsen, Martin C

    2012-01-01

    During myogenesis, human satellite cells differentiate and form multinucleated myotubes, while a fraction of the human satellite cells enter quiescence. These quiescent satellite cells are able to activate, proliferate and contribute to muscle regeneration. Post-transcriptional regulation of

  12. Use of Advanced Solar Cells for Commercial Communication Satellites

    Science.gov (United States)

    Bailey, Sheila G.; Landis, Geoffrey A.

    1995-01-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  13. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle.

    Science.gov (United States)

    McCarthy, John J; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B; Srikuea, Ratchakrit; Lawson, Benjamin A; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S; Esser, Karyn A; Dupont-Versteegden, Esther E; Peterson, Charlotte A

    2011-09-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca(2+) sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells.

  14. Effective fiber hypertrophy in satellite cell-depleted skeletal muscle

    Science.gov (United States)

    McCarthy, John J.; Mula, Jyothi; Miyazaki, Mitsunori; Erfani, Rod; Garrison, Kelcye; Farooqui, Amreen B.; Srikuea, Ratchakrit; Lawson, Benjamin A.; Grimes, Barry; Keller, Charles; Van Zant, Gary; Campbell, Kenneth S.; Esser, Karyn A.; Dupont-Versteegden, Esther E.; Peterson, Charlotte A.

    2011-01-01

    An important unresolved question in skeletal muscle plasticity is whether satellite cells are necessary for muscle fiber hypertrophy. To address this issue, a novel mouse strain (Pax7-DTA) was created which enabled the conditional ablation of >90% of satellite cells in mature skeletal muscle following tamoxifen administration. To test the hypothesis that satellite cells are necessary for skeletal muscle hypertrophy, the plantaris muscle of adult Pax7-DTA mice was subjected to mechanical overload by surgical removal of the synergist muscle. Following two weeks of overload, satellite cell-depleted muscle showed the same increases in muscle mass (approximately twofold) and fiber cross-sectional area with hypertrophy as observed in the vehicle-treated group. The typical increase in myonuclei with hypertrophy was absent in satellite cell-depleted fibers, resulting in expansion of the myonuclear domain. Consistent with lack of nuclear addition to enlarged fibers, long-term BrdU labeling showed a significant reduction in the number of BrdU-positive myonuclei in satellite cell-depleted muscle compared with vehicle-treated muscle. Single fiber functional analyses showed no difference in specific force, Ca2+ sensitivity, rate of cross-bridge cycling and cooperativity between hypertrophied fibers from vehicle and tamoxifen-treated groups. Although a small component of the hypertrophic response, both fiber hyperplasia and regeneration were significantly blunted following satellite cell depletion, indicating a distinct requirement for satellite cells during these processes. These results provide convincing evidence that skeletal muscle fibers are capable of mounting a robust hypertrophic response to mechanical overload that is not dependent on satellite cells. PMID:21828094

  15. Human Satellite Cell Transplantation and Regeneration from Diverse Skeletal Muscles

    Directory of Open Access Journals (Sweden)

    Xiaoti Xu

    2015-09-01

    Full Text Available Identification of human satellite cells that fulfill muscle stem cell criteria is an unmet need in regenerative medicine. This hurdle limits understanding how closely muscle stem cell properties are conserved among mice and humans and hampers translational efforts in muscle regeneration. Here, we report that PAX7 satellite cells exist at a consistent frequency of 2–4 cells/mm of fiber in muscles of the human trunk, limbs, and head. Xenotransplantation into mice of 50–70 fiber-associated, or 1,000–5,000 FACS-enriched CD56+/CD29+ human satellite cells led to stable engraftment and formation of human-derived myofibers. Human cells with characteristic PAX7, CD56, and CD29 expression patterns populated the satellite cell niche beneath the basal lamina on the periphery of regenerated fibers. After additional injury, transplanted satellite cells robustly regenerated to form hundreds of human-derived fibers. Together, these findings conclusively delineate a source of bona-fide endogenous human muscle stem cells that will aid development of clinical applications.

  16. Design and Simulation of a Fused Silica Space Cell Culture and Observation Cavity with Microfluidic and Temperature Controlling

    Directory of Open Access Journals (Sweden)

    Shangchun Fan

    2013-01-01

    Full Text Available We report a principle prototype of space animal cell perfusion culture and observation. Unlike previous work, our cell culture system cannot only realize microfluidic and temperature controlling, automatic observation, and recording but also meet an increasing cell culture at large scale operation and overcome shear force for animal cells. A key component in the system is ingenious structural fused silica cell culture cavity with the wedge-shaped connection. Finite volume method (FVM is applied to calculate its multipoint flow field, pressure field, axial velocity, tangential velocity, and radial velocity. In order to provide appropriate flow rate, temperature, and shear force for space animal cell culture, a closed-loop microfluidic circuit and proportional, integrating, and differentiation (PID algorithm are employed. This paper also illustrates system architecture and operating method of the principle prototype. The dynamic culture, autofocus observation, and recording of M763 cells are performed successfully within 72 h in the laboratory environment. This research can provide a reference for space flight mission that carries an apparatus with similar functions.

  17. [Molecular mechanism maintaining muscle satellite cells and the roles in sarcopenia.

    Science.gov (United States)

    Takemoto, Yusei; Fukada, So-Ichiro

    2017-01-01

    Skeletal muscle has its stem cell named satellite cell. The absence of satellite cells does not allow muscle regeneration, it is unquestionable that satellite cell is indispensable for muscle regeneration processes. A certain number of satellite cells appear to be necessary for the successful muscle regeneration, meaning the maintenance of the satellite cells is essential for the functional homeostasis of skeletal muscle. Recent studies have revealed the molecular mechanism underlying satellite cell maintenance in a steady state. A loss of those molecules responsible for the maintenance often results in decreased satellite cell pool and reduced regeneration ability. On the other hand, the contribution of satellite cells to muscle hypertrophy or aged-related atrophy(sarcopenia)is controversial. In this review, we will introduce the molecules that regulate satellite cells homeostasis in the dormant state and then further discuss the recent results on the roles of satellite cell in sarcopenia.

  18. Spherical Fused Silica Cells Filled with Pure Helium for NMR-Magnetometry

    CERN Document Server

    Maul, Andreas; Heil, Werner; Nikiel, Anna; Otten, Ernst; Petrich, Andreas; Schmidt, Thomas

    2015-01-01

    High magnetic fields (> 1 T) are measured by NMR magnetometers with un-rivaled precision if the precessing spin sample provides long coherence times. The longest coherence times are found in diluted ${}^{3}$He samples, which can be hyperpolarized for sufficient signal strength. In order to have minimal influence on the homogeneity and value of the measured magnetic field the optimal container for the ${}^{3}$He should be a perfect sphere. A fused silica sphere with an inner diameter of 8 mm and an outer diameter of 12 mm was made from two hemispheres by diffusion bonding leaving only a small hole for cleaning and evacuation. This hole was closed in vacuum by a CO${}_{2}$ laser and the inner volume was filled with a few mbars of ${}^3$He via wall permeation. NMR-measurements on such a sample had coherence times of 5 min. While the hemispheres were produced with < 1 $\\mu$m deviation from sphericity, the bonding left a step of ca. 50 $\\mu$m at maximum. The influence of such a mismatch, its orientation and mat...

  19. Spherical fused silica cells filled with pure helium for nuclear magnetic resonance-magnetometry

    Energy Technology Data Exchange (ETDEWEB)

    Maul, Andreas; Blümler, Peter, E-mail: bluemler@uni-mainz.de; Heil, Werner; Nikiel, Anna; Otten, Ernst [Institute of Physics, Johannes Gutenberg University, Staudingerweg 7, 55128 Mainz (Germany); Petrich, Andreas; Schmidt, Thomas [ifw Günter-Köhler-Institut für Fügetechnik und Werkstoffprüfung GmbH, Otto-Schott-Str. 13, 07745 Jena (Germany)

    2016-01-15

    High magnetic fields (>1 T) are measured by NMR magnetometers with unrivaled precision if the precessing spin sample provides long coherence times. The longest coherence times are found in diluted {sup 3}He samples, which can be hyperpolarized for sufficient signal strength. In order to have minimal influence on the homogeneity and value of the measured magnetic field, the optimal container for the {sup 3}He should be a perfect sphere. A fused silica sphere with an inner diameter of 8 mm and an outer diameter of 12 mm was made from two hemispheres by diffusion bonding leaving only a small hole for cleaning and evacuation. This hole was closed in vacuum by a CO{sub 2} laser and the inner volume was filled with a few mbars of {sup 3}He via wall permeation. NMR-measurements on such a sample had coherence times of 5 min. While the hemispheres were produced with <1 μm deviation from sphericity, the bonding left a step of ca. 50 μm at maximum. The influence of such a mismatch, its orientation, and the immediate environment of the sample is analyzed by FEM-simulations and discussed in view of coherence times and absolute field measurements.

  20. Development of Cell Lines Stably Expressing Staphylococcal Nuclease Fused to Dengue 2 Virus Capsid Protein for CTVI

    Institute of Scientific and Technical Information of China (English)

    Cheng-Feng QIN; E-De QIN

    2004-01-01

    To explore the potential application of capsid-targeted viral inactivation(CTVI)strategy in prophylactic model against dengue virus(DV)infection,here we fused a Ca2+-dependent nuclease,staphylococcal nuclease(SN),to the capsid protein of dengue 2 virus(D2C)at the carboxyl terminal,and constructed the desired expression plasmid pc/D2C-SN and control plasmids pc/D2C-SN* and pc/D2C.A mammalian cell line BHK-21 was transfected by electroporation with those plasmids and thereafter selected by 5 μg/ml blasticidin.The resistant cell clones were then expanding cultured and screened by RT-PCR and Western Blot assays.The nuclease activity of the expressed fusion protein D2C-SN was analyzed by in vitro DNA digestion assay.It was confirmed cell lines stably expressing D2C-SN and control constructs were obtained.The intracellular expressed fusion protein D2C-SN had ideal nuclease activity and no cytotoxicity on mammalian cells.Those engineered cell lines provided the experimental system for CTVI application in prophylactic model and paved the new road for combating DV infection with CTVI.

  1. Non-fused phospholes as fluorescent probes for imaging of lipid droplets in living cells

    Science.gov (United States)

    Öberg, Elisabet; Appelqvist, Hanna; Nilsson, K. Peter R.

    2017-04-01

    Molecular tools for fluorescent imaging of specific compartments in cells are essential for understanding the function and activity of cells. Here, we report the synthesis of a series of pyridyl- and thienyl-substituted phospholes and the evaluation of these dyes for fluorescent imaging of cells. The thienyl-substituted phospholes proved to be successful for staining of cultured normal and malignant cells due to their fluorescent properties and low toxicity. Co-staining experiments demonstrated that these probes target lipid droplets, which are, lipid-storage organelles found in the cytosol of nearly all cell types. Our findings confirm that thienyl-substituted phospholes can be utilized as fluorescent tools for vital staining of cells, and we foresee that these fluorescent dyes might be used in studies to unravel the roles that lipid droplets play in cellular physiology and their role in diseases.

  2. Intestinal cell targeting of a stable recombinant Cu-Zn SOD from Cucumis melo fused to a gliadin peptide.

    Science.gov (United States)

    Intes, Laurent; Bahut, Muriel; Nicole, Pascal; Couvineau, Alain; Guette, Catherine; Calenda, Alphonse

    2012-05-31

    The mRNA encoding full length chloroplastic Cu-Zn SOD (superoxide dismutase) of Cucumis melo (Cantaloupe melon) was cloned. This sequence was then used to generate a mature recombinant SOD by deleting the first 64 codons expected to encode a chloroplastic peptide signal. A second hybrid SOD was created by inserting ten codons to encode a gliadin peptide at the N-terminal end of the mature SOD. Taking account of codon bias, both recombinant proteins were successfully expressed and produced in Escherichia coli. Both recombinant SODs display an enzymatic activity of ~5000U mg(-1) and were shown to be stable for at least 4h at 37°C in biological fluids mimicking the conditions of intestinal transit. These recombinant proteins were capable in vitro, albeit at different levels, of reducing ROS-induced-apoptosis of human epithelial cells. They also stimulated production and release in a time-dependent manner of an autologous SOD activity from cells located into jejunum biopsies. Nevertheless, the fused gliadin peptide enable the recombinant Cu-Zn SOD to maintain a sufficiently sustained interaction with the intestinal cells membrane in vivo rather than being eliminated with the flow. According to these observations, the new hybrid Cu-Zn SOD should show promise in applications for managing inflammatory bowel diseases.

  3. Impaired energy metabolism of senescent muscle satellite cells is associated with oxidative modifications of glycolytic enzymes

    DEFF Research Database (Denmark)

    Baraibar, Martín A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina

    2016-01-01

    Accumulation of oxidized proteins is a hallmark of cellular and organismal aging. Adult muscle stem cell (or satellite cell) replication and differentiation is compromised with age contributing to sarcopenia. However, the molecular events related to satellite cell dysfunction during aging...

  4. Satellite glial cells in sensory ganglia: its role in pain

    Directory of Open Access Journals (Sweden)

    Filipa Alexandra Leite Costa

    2015-02-01

    Full Text Available BACKGROUND AND OBJECTIVES: Satellite glial cells in sensory ganglia are a recent subject of research in the field of pain and a possible therapeutic target in the future. Therefore, the aim of this study was to summarize some of the important physiological and morphological characteristics of these cells and gather the most relevant scientific evidence about its possible role in the development of chronic pain. CONTENT: In the sensory ganglia, each neuronal body is surrounded by satellite glial cells forming distinct functional units. This close relationship enables bidirectional communication via a paracrine signaling between those two cell types. There is a growing body of evidence that glial satellite cells undergo structural and biochemical changes after nerve injury, which influence neuronal excitability and consequently the development and/or maintenance of pain in different animal models of chronic pain. CONCLUSIONS: Satellite glial cells are important in the establishment of physiological pain, in addition to being a potential target for the development of new pain treatments.

  5. Cre Fused with RVG Peptide Mediates Targeted Genome Editing in Mouse Brain Cells In Vivo

    Directory of Open Access Journals (Sweden)

    Zhiyuan Zou

    2016-12-01

    Full Text Available Cell penetrating peptides (CPPs are short peptides that can pass through cell membranes. CPPs can facilitate the cellular entry of proteins, macromolecules, nanoparticles and drugs. RVG peptide (RVG hereinafter is a 29-amino-acid CPP derived from a rabies virus glycoprotein that can cross the blood-brain barrier (BBB and enter brain cells. However, whether RVG can be used for genome editing in the brain has not been reported. In this work, we combined RVG with Cre recombinase for bacterial expression. The purified RVG-Cre protein cut plasmids in vitro and traversed cell membranes in cultured Neuro2a cells. By tail vein-injecting RVG-Cre into Cre reporter mouse lines mTmG and Rosa26lacZ, we demonstrated that RVG-Cre could target brain cells and achieve targeted somatic genome editing in adult mice. This direct delivery of the gene-editing enzyme protein into mouse brains with RVG is much safer than plasmid- or viral-based methods, holding promise for further applications in the treatment of various brain diseases.

  6. Satellite cell depletion prevents fiber hypertrophy in skeletal muscle.

    Science.gov (United States)

    Egner, Ingrid M; Bruusgaard, Jo C; Gundersen, Kristian

    2016-08-15

    The largest mammalian cells are the muscle fibers, and they have multiple nuclei to support their large cytoplasmic volumes. During hypertrophic growth, new myonuclei are recruited from satellite stem cells into the fiber syncytia, but it was recently suggested that such recruitment is not obligatory: overload hypertrophy after synergist ablation of the plantaris muscle appeared normal in transgenic mice in which most of the satellite cells were abolished. When we essentially repeated these experiments analyzing the muscles by immunohistochemistry and in vivo and ex vivo imaging, we found that overload hypertrophy was prevented in the satellite cell-deficient mice, in both the plantaris and the extensor digitorum longus muscles. We attribute the previous findings to a reliance on muscle mass as a proxy for fiber hypertrophy, and to the inclusion of a significant number of regenerating fibers in the analysis. We discuss that there is currently no model in which functional, sustainable hypertrophy has been unequivocally demonstrated in the absence of satellite cells; an exception is re-growth, which can occur using previously recruited myonuclei without addition of new myonuclei. © 2016. Published by The Company of Biologists Ltd.

  7. Lymphocyte activation by purified HLA-DR molecules fused into autochthonous "stimulating cells".

    Science.gov (United States)

    Diu, A; Abikar, K; Rode, H N; Gordon, J

    1985-08-01

    Affinity-purified Ia molecules derived from the Daudi cell line were reconstituted into vesicles with Sendai virus envelope glycoproteins. These vesicles inserted into human peripheral leukocytes could induce stimulation of autologous lymphocytes, as measured by thymidine uptake, 6 days later. It is suggested that this method could provide a means to study allostimulation at the molecular level.

  8. Neonatal Satellite Cells Form Small Myotubes in Vitro

    NARCIS (Netherlands)

    Carvajal Monroy, P.L.; Grefte, S.; Kuijpers-Jagtman, A.M.; Den Hoff, Von J.W.; Wagener, F.A.D.T.G.

    2017-01-01

    Although palatal muscle reconstruction in patients with cleft palate takes place during early childhood, normal speech development is often not achieved. We hypothesized that the intrinsic properties of head satellite cells (SCs) and the young age of these patients contribute to the poor muscle

  9. Substrate elasticity affects bovine satellite cell activation kinetics in vitro.

    Science.gov (United States)

    Lapin, M R; Gonzalez, J M; Johnson, S E

    2013-05-01

    Satellite cells support efficient postnatal skeletal muscle hypertrophy through fusion into the adjacent muscle fiber. Nuclear contribution allows for maintenance of the fiber myonuclear domain and proficient transcription of myogenic genes. Niche growth factors affect satellite cell biology; however, the interplay between fiber elasticity and microenvironment proteins remains largely unknown. The objective of the experiment was to examine the effects of hepatocyte growth factor (HGF) and surface elasticity on bovine satellite cell (BSC) activation kinetics in vitro. Young's elastic modulus was calculated for the semimembranosus (SM) and LM muscles of young bulls (5 d; n = 8) and adult cows (27 mo; n = 4) cattle. Results indicate that LM elasticity decreased (P Young's modulus for the SM was noted. Bovine satellite cells were seeded atop polyacrylamide bioscaffolds with surface elasticities that mimic young bull and adult cow LM or traditional cultureware. Cells were maintained in low-serum media supplemented with 5 ng/mL HGF or vehicle only for 24 or 48 h. Activation was evaluated by proliferating cell nuclear antigen (PCNA) immunocytochemistry. Results indicate that BSC maintained on rigid surfaces were activated at 24 h and refractive to HGF supplementation. By contrast, fewer (P young bull (8.1 ± 1.7 kPa) or adult cow (14.6 ± 1.6 kPa) LM. Supplementation with HGF promoted activation of BSC cultured on bioscaffolds as measured by an increase (P muscle stem cells (P > 0.05). However, with increasing surface elasticity, an increase (P muscle progenitors was observed. These results confirm that biophysical and biochemical signals regulate BSC activation.

  10. RBP-J (Rbpsuh) is essential to maintain muscle progenitor cells and to generate satellite cells.

    Science.gov (United States)

    Vasyutina, Elena; Lenhard, Diana C; Wende, Hagen; Erdmann, Bettina; Epstein, Jonathan A; Birchmeier, Carmen

    2007-03-13

    In the developing muscle, a pool of myogenic progenitor cells is formed and maintained. These resident progenitors provide a source of cells for muscle growth in development and generate satellite cells in the perinatal period. By the use of conditional mutagenesis in mice, we demonstrate here that the major mediator of Notch signaling, the transcription factor RBP-J, is essential to maintain this pool of progenitor cells in an undifferentiated state. In the absence of RBP-J, these cells undergo uncontrolled myogenic differentiation, leading to a depletion of the progenitor pool. This results in a lack of muscle growth in development and severe muscle hypotrophy. In addition, satellite cells are not formed late in fetal development in conditional RBP-J mutant mice. We conclude that RBP-J is required in the developing muscle to set aside proliferating progenitors and satellite cells.

  11. Muscle Interstitial Cells: A Brief Field Guide to Non-satellite Cell Populations in Skeletal Muscle.

    Science.gov (United States)

    Tedesco, Francesco Saverio; Moyle, Louise A; Perdiguero, Eusebio

    2017-01-01

    Skeletal muscle regeneration is mainly enabled by a population of adult stem cells known as satellite cells. Satellite cells have been shown to be indispensable for adult skeletal muscle repair and regeneration. In the last two decades, other stem/progenitor cell populations resident in the skeletal muscle interstitium have been identified as "collaborators" of satellite cells during regeneration. They also appear to have a key role in replacing skeletal muscle with adipose, fibrous, or bone tissue in pathological conditions. Here, we review the role and known functions of these different interstitial skeletal muscle cell types and discuss their role in skeletal muscle tissue homeostasis, regeneration, and disease, including their therapeutic potential for cell transplantation protocols.

  12. The satellite cell in male and female, developing and adult mouse muscle: distinct stem cells for growth and regeneration.

    Directory of Open Access Journals (Sweden)

    Alice Neal

    Full Text Available Satellite cells are myogenic cells found between the basal lamina and the sarcolemma of the muscle fibre. Satellite cells are the source of new myofibres; as such, satellite cell transplantation holds promise as a treatment for muscular dystrophies. We have investigated age and sex differences between mouse satellite cells in vitro and assessed the importance of these factors as mediators of donor cell engraftment in an in vivo model of satellite cell transplantation. We found that satellite cell numbers are increased in growing compared to adult and in male compared to female adult mice. We saw no difference in the expression of the myogenic regulatory factors between male and female mice, but distinct profiles were observed according to developmental stage. We show that, in contrast to adult mice, the majority of satellite cells from two week old mice are proliferating to facilitate myofibre growth; however a small proportion of these cells are quiescent and not contributing to this growth programme. Despite observed changes in satellite cell populations, there is no difference in engraftment efficiency either between satellite cells derived from adult or pre-weaned donor mice, male or female donor cells, or between male and female host muscle environments. We suggest there exist two distinct satellite cell populations: one for muscle growth and maintenance and one for muscle regeneration.

  13. RBP-J (Rbpsuh) is essential to maintain muscle progenitor cells and to generate satellite cells

    OpenAIRE

    Vasyutina, Elena; Lenhard, Diana C.; Wende, Hagen; Erdmann, Bettina; Epstein, Jonathan A.; Birchmeier, Carmen

    2007-01-01

    In the developing muscle, a pool of myogenic progenitor cells is formed and maintained. These resident progenitors provide a source of cells for muscle growth in development and generate satellite cells in the perinatal period. By the use of conditional mutagenesis in mice, we demonstrate here that the major mediator of Notch signaling, the transcription factor RBP-J, is essential to maintain this pool of progenitor cells in an undifferentiated state. In the absence of RBP-J, these cells unde...

  14. A role for RNA post-transcriptional regulation in satellite cell activation

    Directory of Open Access Journals (Sweden)

    Farina Nicholas H

    2012-10-01

    Full Text Available Abstract Background Satellite cells are resident skeletal muscle stem cells responsible for muscle maintenance and repair. In resting muscle, satellite cells are maintained in a quiescent state. Satellite cell activation induces the myogenic commitment factor, MyoD, and cell cycle entry to facilitate transition to a population of proliferating myoblasts that eventually exit the cycle and regenerate muscle tissue. The molecular mechanism involved in the transition of a quiescent satellite cell to a transit-amplifying myoblast is poorly understood. Methods Satellite cells isolated by FACS from uninjured skeletal muscle and 12 h post-muscle injury from wild type and Syndecan-4 null mice were probed using Affymetrix 430v2 gene chips and analyzed by Spotfiretm and Ingenuity Pathway analysis to identify gene expression changes and networks associated with satellite cell activation, respectively. Additional analyses of target genes identify miRNAs exhibiting dynamic changes in expression during satellite cell activation. The function of the miRNAs was assessed using miRIDIAN hairpin inhibitors. Results An unbiased gene expression screen identified over 4,000 genes differentially expressed in satellite cells in vivo within 12 h following muscle damage and more than 50% of these decrease dramatically. RNA binding proteins and genes involved in post-transcriptional regulation were significantly over-represented whereas splicing factors were preferentially downregulated and mRNA stability genes preferentially upregulated. Furthermore, six computationally identified miRNAs demonstrated novel expression through muscle regeneration and in satellite cells. Three of the six miRNAs were found to regulate satellite cell fate. Conclusions The quiescent satellite cell is actively maintained in a state poised to activate in response to external signals. Satellite cell activation appears to be regulated by post-transcriptional gene regulation.

  15. Dendritic cells pulsed with alpha-fetoprotein and mutant P53 fused gene induce bi-targeted cytotoxic T lymphocyte response against hepatic carcinoma.

    Science.gov (United States)

    Ren, Jun; Jia, Jun; Zhang, Hongmei; Zhang, Liwang; Ma, Bo; Jiang, Hanfang; Di, Lijun; Song, Guohong; Yu, Jing

    2008-07-01

    Dendritic cell (DC)-based immunotherapy is rapidly emerging as a promising treatment in cancer therapy. We had previously shown that DC pulsed with either defined mRNA of tumor antigen (Ag) such as alpha-fetoprotein (AFP), or total RNA of hepatocellular carcinoma (HCC) could elicit Ag-specific cytotoxic T lymphocyte (CTL) response. Therefore, we suggested a novel DC-based therapeutic method, in which DCs derived from CD34(+) cells enriched peripheral blood mononuclear cells were pulsed with liposome-coated AFP and mutant P53 (mtP53) fused gene pEGFP-C3/AFP-mtP53 to induce bi-targeted specific CTL responses against HCC. Three different genotype HCC cell lines, HepG2 (human histocompatibility leukocyte antigens (HLA) A2 positive, AFP expressing positive, P53 expressing negative), SMMC7721 (HLA A2 positive, neither AFP nor P53 expressing positive), and HMCC97 (HLA A2 positive, both AFP and P53 expressing positive) were selected as targets for CTL responses. An important finding was that DCs pulsed with the liposome-coated fused gene could evoke more intensive bi-targeted Ag-specific CTL responses against HMCC97 than DCs pulsed with either AFP or P53 single gene (P gene of different Ags might induce more extensive multitargeted antitumor immunity.

  16. Polymer optical fiber fuse

    CERN Document Server

    Mizuno, Yosuke; Tanaka, Hiroki; Nakamura, Kentaro

    2013-01-01

    Although high-transmission-capacity optical fibers are in demand, the problem of the fiber fuse phenomenon needs to be resolved to prevent the destruction of fibers. As polymer optical fibers become more prevalent, clarifying their fuse properties has become important. Here, we experimentally demonstrate a fuse propagation velocity of 21.9 mm/s, which is 1 to 2 orders of magnitude slower than that in standard silica fibers. The achieved threshold power density and proportionality constant between the propagation velocity and the power density are respectively 1/186 of and 16.8 times the values for silica fibers. An oscillatory continuous curve instead of periodic voids is formed after the passage of the fuse. An easy fuse termination method is presented herein, along with its potential plasma applications.

  17. Impaired energy metabolism of senescent muscle satellite cells is associated with oxidative modifications of glycolytic enzymes

    DEFF Research Database (Denmark)

    Baraibar, Martín A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina

    2016-01-01

    Accumulation of oxidized proteins is a hallmark of cellular and organismal aging. Adult muscle stem cell (or satellite cell) replication and differentiation is compromised with age contributing to sarcopenia. However, the molecular events related to satellite cell dysfunction during aging are not...

  18. Discovery of Novel Small Molecules that Activate Satellite Cell Proliferation and Enhance Repair of Damaged Muscle.

    Science.gov (United States)

    Billin, Andrew N; Bantscheff, Marcus; Drewes, Gerard; Ghidelli-Disse, Sonja; Holt, Jason A; Kramer, Henning F; McDougal, Alan J; Smalley, Terry L; Wells, Carrow I; Zuercher, William J; Henke, Brad R

    2016-02-19

    Skeletal muscle progenitor stem cells (referred to as satellite cells) represent the primary pool of stem cells in adult skeletal muscle responsible for the generation of new skeletal muscle in response to injury. Satellite cells derived from aged muscle display a significant reduction in regenerative capacity to form functional muscle. This decrease in functional recovery has been attributed to a decrease in proliferative capacity of satellite cells. Hence, agents that enhance the proliferative abilities of satellite cells may hold promise as therapies for a variety of pathological settings, including repair of injured muscle and age- or disease-associated muscle wasting. Through phenotypic screening of isolated murine satellite cells, we identified a series of 2,4-diaminopyrimidines (e.g., 2) that increased satellite cell proliferation. Importantly, compound 2 was effective in accelerating repair of damaged skeletal muscle in an in vivo mouse model of skeletal muscle injury. While these compounds were originally prepared as c-Jun N-terminal kinase 1 (JNK-1) inhibitors, structure-activity analyses indicated JNK-1 inhibition does not correlate with satellite cell activity. Screening against a broad panel of kinases did not result in identification of an obvious molecular target, so we conducted cell-based proteomics experiments in an attempt to identify the molecular target(s) responsible for the potentiation of the satellite cell proliferation. These data provide the foundation for future efforts to design improved small molecules as potential therapeutics for muscle repair and regeneration.

  19. Rb1 gene inactivation expands satellite cell and postnatal myoblast pools.

    Science.gov (United States)

    Hosoyama, Tohru; Nishijo, Koichi; Prajapati, Suresh I; Li, Guangheng; Keller, Charles

    2011-06-03

    Satellite cells are well known as a postnatal skeletal muscle stem cell reservoir that under injury conditions participate in repair. However, mechanisms controlling satellite cell quiescence and activation are the topic of ongoing inquiry by many laboratories. In this study, we investigated whether loss of the cell cycle regulatory factor, pRb, is associated with the re-entry of quiescent satellite cells into replication and subsequent stem cell expansion. By ablation of Rb1 using a Pax7CreER,Rb1 conditional mouse line, satellite cell number was increased 5-fold over 6 months. Furthermore, myoblasts originating from satellite cells lacking Rb1 were also increased 3-fold over 6 months, while terminal differentiation was greatly diminished. Similarly, Pax7CreER,Rb1 mice exhibited muscle fiber hypotrophy in vivo under steady state conditions as well as a delay of muscle regeneration following cardiotoxin-mediated injury. These results suggest that cell cycle re-entry of quiescent satellite cells is accelerated by lack of Rb1, resulting in the expansion of both satellite cells and their progeny in adolescent muscle. Conversely, that sustained Rb1 loss in the satellite cell lineage causes a deficit of muscle fiber formation. However, we also show that pharmacological inhibition of protein phosphatase 1 activity, which will result in pRb inactivation accelerates satellite cell activation and/or expansion in a transient manner. Together, our results raise the possibility that reversible pRb inactivation in satellite cells and inhibition of protein phosphorylation may provide a new therapeutic tool for muscle atrophy by short term expansion of the muscle stem cells and myoblast pool.

  20. Isolation, culture and biological characteristics of multipotent porcine skeletal muscle satellite cells.

    Science.gov (United States)

    Yang, Jinjuan; Liu, Hao; Wang, Kunfu; Li, Lu; Yuan, Hongyi; Liu, Xueting; Liu, Yingjie; Guan, Weijun

    2017-03-02

    Skeletal muscle has a huge regenerative potential for postnatal muscle growth and repair, which mainly depends on a kind of muscle progenitor cell population, called satellite cell. Nowadays, the majority of satellite cells were obtained from human, mouse, rat and other animals but rarely from pig. In this article, the porcine skeletal muscle satellite cells were isolated and cultured in vitro. The expression of surface markers of satellite cells was detected by immunofluorescence and RT-PCR assays. The differentiation capacity was assessed by inducing satellite cells into adipocytes, myoblasts and osteoblasts. The results showed that satellite cells isolated from porcine tibialis anterior were subcultured up to 12 passages and were positive for Pax7, Myod, c-Met, desmin, PCNA and NANOG but were negative for Myogenin. Satellite cells were also induced to differentiate into adipocytes, osteoblasts and myoblasts, respectively. These findings indicated that porcine satellite cells possess similar biological characteristics of stem cells, which may provide theoretical basis and experimental evidence for potential therapeutic application in the treatment of dystrophic muscle and other muscle injuries.

  1. Functional Use Database (FUse)

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are five different files for this dataset: 1. A dataset listing the reported functional uses of chemicals (FUse) 2. All 729 ToxPrint descriptors obtained from...

  2. Satellite Cells Contribution to Exercise Mediated Muscle Hypertrophy and Repair

    Science.gov (United States)

    Bazgir, Behzad; Fathi, Rouhollah; Rezazadeh Valojerdi, Mojtaba; Mozdziak, Paul; Asgari, Alireza

    2017-01-01

    Satellite cells (SCs) are the most abundant skeletal muscle stem cells. They are widely recognized for their contributions to maintenance of muscle mass, regeneration and hypertrophy during the human life span. These cells are good candidates for cell therapy due to their self-renewal capabilities and presence in an undifferentiated form. Presently, a significant gap exists between our knowledge of SCs behavior and their application as a means for human skeletal muscle tissue repair and regeneration. Both physiological and pathological stimuli potentially affect SCs activation, proliferation, and terminal differentiation the former category being the focus of this article. Activation of SCs occurs following exercise, post-training micro-injuries, and electrical stimulation. Exercise, as a potent and natural stimulus, is at the center of numerous studies on SC activation and relevant fields. According to research, different exercise modalities end with various effects. This review article attempts to picture the state of the art of the SCs life span and their engagement in muscle regeneration and hypertrophy in exercise. PMID:28042532

  3. Satellite Cells Contribution to Exercise Mediated Muscle Hypertrophy and Repair

    Directory of Open Access Journals (Sweden)

    Behzad Bazgir

    2016-10-01

    Full Text Available Satellite cells (SCs are the most abundant skeletal muscle stem cells. They are widely recognized for their contributions to maintenance of muscle mass, regeneration and hypertrophy during the human life span. These cells are good candidates for cell therapy due to their self-renewal capabilities and presence in an undifferentiated form. Presently, a significant gap exists between our knowledge of SCs behavior and their application as a means for human skeletal muscle tissue repair and regeneration. Both physiological and pathological stimuli potentially affect SCs activation, proliferation, and terminal differentiation - the former category being the focus of this article. Activation of SCs occurs following exercise, post-training micro-injuries, and electrical stimulation. Exercise, as a potent and natural stimulus, is at the center of numerous studies on SC activation and relevant fields. According to research, different exercise modalities end with various effects. This review article attempts to picture the state of the art of the SCs life span and their engagement in muscle regeneration and hypertrophy in exercise.

  4. Globular adiponectin activates motility and regenerative traits of muscle satellite cells.

    Directory of Open Access Journals (Sweden)

    Tania Fiaschi

    Full Text Available Regeneration of adult injured skeletal muscle is due to activation of satellite cells, a population of stem cells resident beneath the basal lamina. Thus, information on soluble factors affecting satellite cell activation, as well as migration towards injury and fusion into new myofibers are essential. Here, we show that globular adiponectin (gAd, positively affects several features of muscle satellite cells. gAd activates satellite cells to exit quiescence and increases their recruitment towards myotubes. gAd elicits in satellite cells a specific motility program, involving activation of the small GTPase Rac1, as well as expression of Snail and Twist transcription factors driving a proteolytic motility, useful to reach the site of injury. We show that satellite cells produce autocrine full length adiponectin (fAd, which is converted to gAd by activated macrophages. In turns, gAd concurs to attract to the site of injury both satellite cells and macrophages and induces myogenesis in muscle satellite cells. Thus, these findings add a further role for gAd in skeletal muscle, including the hormone among factors participating in muscle regeneration.

  5. Differential satellite cell density of type I and II fibres with lifelong endurance running in old men

    DEFF Research Database (Denmark)

    Mackey, Abigail; Karlsen, A; Couppé, C

    2014-01-01

    between these variables were determined. RESULTS: In O-Un and O-Tr, type II fibres were smaller and contained fewer satellite cells than type I fibres. However, when expressed relative to fibre area, the difference in satellite cell content between fibre types was eliminated in O-Tr, but not O...... the satellite cell pool and (ii) is associated with a similar density of satellite cells in type I and II fibres despite a failure to preserve the equal fibre type distribution of satellite cells observed in young individuals. Taken together, these data reveal a differential regulation of satellite cell content...

  6. Sox2 promotes survival of satellite glial cells in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Koike, Taro, E-mail: koiket@hirakata.kmu.ac.jp; Wakabayashi, Taketoshi; Mori, Tetsuji; Hirahara, Yukie; Yamada, Hisao

    2015-08-14

    Sox2 is a transcriptional factor expressed in neural stem cells. It is known that Sox2 regulates cell differentiation, proliferation and survival of the neural stem cells. Our previous study showed that Sox2 is expressed in all satellite glial cells of the adult rat dorsal root ganglion. In this study, to examine the role of Sox2 in satellite glial cells, we establish a satellite glial cell-enriched culture system. Our culture method succeeded in harvesting satellite glial cells with the somata of neurons in the dorsal root ganglion. Using this culture system, Sox2 was downregulated by siRNA against Sox2. The knockdown of Sox2 downregulated ErbB2 and ErbB3 mRNA at 2 and 4 days after siRNA treatment. MAPK phosphorylation, downstream of ErbB, was also inhibited by Sox2 knockdown. Because ErbB2 and ErbB3 are receptors that support the survival of glial cells in the peripheral nervous system, apoptotic cells were also counted. TUNEL-positive cells increased at 5 days after siRNA treatment. These results suggest that Sox2 promotes satellite glial cell survival through the MAPK pathway via ErbB receptors. - Highlights: • We established satellite glial cell culture system. • Function of Sox2 in satellite glial cell was examined using siRNA. • Sox2 knockdown downregulated expression level of ErbB2 and ErbB3 mRNA. • Sox2 knockdown increased apoptotic satellite glial cell. • Sox2 promotes satellite glial cell survival through ErbB signaling.

  7. Assessment of satellite cell number and activity status in human skeletal muscle biopsies

    DEFF Research Database (Denmark)

    Mackey, Abigail; Kjaer, Michael; Charifi, Nadia;

    2009-01-01

    The primary aim of our study was to validate the assessment of myonuclear and satellite cell number in biopsies from human skeletal muscle. We found that 25 type I and 25 type II fibers are sufficient to estimate the mean number of myonuclei per fiber. In contrast, the assessment of satellite cells...

  8. Isolation and characterization of satellite cells from rat head branchiomeric muscles

    NARCIS (Netherlands)

    Carvajal Monroy, P.L.; Yablonka-Reuveni, Z.; Grefte, Sander; Kuijpers-Jagtman, Anne Marie; Wagener, F.A.D.T.G.; Hoff, Von den J.W.

    2015-01-01

    This protocol describes the isolation of satellite cells from branchiomeric head muscles of a 9 week-old rat. The muscles originate from different branchial arches. Subsequently, the satellite cells are cultured on a spot coating of millimeter size to study their differentiation. This approach avoid

  9. A myogenic precursor cell that could contribute to regeneration in zebrafish and its similarity to the satellite cell.

    Science.gov (United States)

    Siegel, Ashley L; Gurevich, David B; Currie, Peter D

    2013-09-01

    The cellular basis for mammalian muscle regeneration has been an area of intense investigation over recent decades. The consensus is that a specialized self-renewing stem cell, termed the satellite cell, plays a major role during the process of regeneration in amniotes. How broadly this mechanism is deployed within the vertebrate phylogeny remains an open question. A lack of information on the role of cells analogous to the satellite cell in other vertebrate systems is even more unexpected given the fact that satellite cells were first designated in frogs. An intriguing aspect of this debate is that a number of amphibia and many fish species exhibit epimorphic regenerative processes in specific tissues, whereby regeneration occurs by the dedifferentiation of the damaged tissue, without deploying specialized stem cell populations analogous to satellite cells. Hence, it is feasible that a cellular process completely distinct from that deployed during mammalian muscle regeneration could operate in species capable of epimorphic regeneration. In this minireview, we examine the evidence for the broad phylogenetic distribution of satellite cells. We conclude that, in the vertebrates examined so far, epimorphosis does not appear to be deployed during muscle regeneration, and that analogous cells expressing similar marker genes to satellite cells appear to be deployed during the regenerative process. However, the functional definition of these cells as self-renewing muscle stem cells remains a final hurdle to the definition of the satellite cell as a generic vertebrate cell type.

  10. Stem cells with FGF4-bFGF fused gene enhances the expression of bFGF and improves myocardial repair in rats

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiang-Qi; Chen, Liang-Long, E-mail: xhzlyx@126.com; Fan, Lin; Fang, Jun; Chen, Zhao-Yang; Li, Wei-Wei

    2014-04-25

    Highlights: • BFGF exists only in the cytoplasm of live cells. • BFGF cannot be secreted into the extracellular space to promote cell growth. • We combine the secretion-promoting signal peptide of FGF4. • We successfully modified BMSCs with the fused genes of FGF4-bFGF. • We promoted the therapeutic effects of transplanted BMSCs in myocardial infarction. - Abstract: The aim of this study was to investigate whether the modification of bone marrow-derived mesenchymal stem cells (BMSCs) with the fused FGF4 (fibroblast growth factor 4)-bFGF (basic fibroblast growth factor) gene could improve the expression and secretion of BFGF, and increase the efficacies in repairing infarcted myocardium. We used In-Fusion technique to construct recombinant lentiviral vectors containing the individual gene of bFGF, enhanced green fluorescent protein (EGFP), or genes of FGF4-bFGF and EGFP, and then transfected these lentiviruses into rat BMSCs. We conducted an in vitro experiment to compare the secretion of bFGF in BMSCs infected by these lentiviruses and also examined their therapeutic effects in the treatment of myocardial infraction in a rodent study. Sixty rats were tested in the following five conditions: Group-SHAM received only sham operation as controls; Group-AMI received only injection of placebo PBS buffer; Group-BMSC, Group-bFGF and Group-FGF4-bFGF received implantation of BMSCs with empty lentivirus, bFGF lentivirus, and FGF4-bFGF lentivirus, respectively. Our results found out that the transplanted FGF4-bFGF BMSCs had the highest survival rate, and also the highest myocardial expression of bFGF and microvascular density as evidenced by Western blotting and immunohistochemistry, respectively. As compared to other groups, the Group-FGF4-BFGF rats had the lowest myocardial fibrotic fraction, and the highest left ventricular ejection fraction. These results suggest that the modification of BMSCs with the FGF4-bFGF fused gene can not only increase the expression of

  11. Porphyrins Fused with Unactivated Polycyclic Aromatic Hydrocarbons

    KAUST Repository

    Diev, Vyacheslav V.

    2012-01-06

    A systematic study of the preparation of porphyrins with extended conjugation by meso,β-fusion with polycyclic aromatic hydrocarbons (PAHs) is reported. The meso-positions of 5,15-unsubstituted porphyrins were readily functionalized with PAHs. Ring fusion using standard Scholl reaction conditions (FeCl 3, dichloromethane) occurs for perylene-substituted porphyrins to give a porphyrin β,meso annulated with perylene rings (0.7:1 ratio of syn and anti isomers). The naphthalene, pyrene, and coronene derivatives do not react under Scholl conditions but are fused using thermal cyclodehydrogenation at high temperatures, giving mixtures of syn and anti isomers of the meso,β-fused porphyrins. For pyrenyl-substituted porphyrins, a thermal method gives synthetically acceptable yields (>30%). Absorption spectra of the fused porphyrins undergo a progressive bathochromic shift in a series of naphthyl (λ max = 730 nm), coronenyl (λ max = 780 nm), pyrenyl (λ max = 815 nm), and perylenyl (λ max = 900 nm) annulated porphyrins. Despite being conjugated with unsubstituted fused PAHs, the β,meso-fused porphyrins are more soluble and processable than the parent nonfused precursors. Pyrenyl-fused porphyrins exhibit strong fluorescence in the near-infrared (NIR) spectral region, with a progressive improvement in luminescent efficiency (up to 13% with λ max = 829 nm) with increasing degree of fusion. Fused pyrenyl-porphyrins have been used as broadband absorption donor materials in photovoltaic cells, leading to devices that show comparatively high photovoltaic efficiencies. © 2011 American Chemical Society.

  12. Notch Signaling Rescues Loss of Satellite Cells Lacking Pax7 and Promotes Brown Adipogenic Differentiation.

    Science.gov (United States)

    Pasut, Alessandra; Chang, Natasha C; Rodriguez, Uxia Gurriaran; Faulkes, Sharlene; Yin, Hang; Lacaria, Melanie; Ming, Hong; Rudnicki, Michael A

    2016-07-12

    Pax7 is a nodal transcription factor that is essential for regulating the maintenance, expansion, and myogenic identity of satellite cells during both neonatal and adult myogenesis. Deletion of Pax7 results in loss of satellite cells and impaired muscle regeneration. Here, we show that ectopic expression of the constitutively active intracellular domain of Notch1 (NICD1) rescues the loss of Pax7-deficient satellite cells and restores their proliferative potential. Strikingly NICD1-expressing satellite cells do not undergo myogenic differentiation and instead acquire a brown adipogenic fate both in vivo and in vitro. NICD-expressing Pax7(-/-) satellite cells fail to upregulate MyoD and instead express the brown adipogenic marker PRDM16. Overall, these results show that Notch1 activation compensates for the loss of Pax7 in the quiescent state and acts as a molecular switch to promote brown adipogenesis in adult skeletal muscle.

  13. Methods for Observing and Quantifying Muscle Satellite Cell Motility and Invasion In Vitro.

    Science.gov (United States)

    Lund, Dane K; McAnulty, Patrick; Siegel, Ashley L; Cornelison, Ddw

    2017-01-01

    Motility and/or chemotaxis of satellite cells has been suggested or observed in multiple in vitro and in vivo contexts. Satellite cell motility also affects the efficiency of muscle regeneration, particularly in the context of engrafted exogenous cells. Consequently, there is keen interest in determining what cell-autonomous and environmental factors influence satellite cell motility and chemotaxis in vitro and in vivo. In addition, the ability of activated satellite cells to relocate in vivo would suggest that they must be able to invade and transit through the extracellular matrix (ECM), which is supported by studies in which alteration or addition of matrix metalloprotease (MMP) activity enhanced the spread of engrafted satellite cells. However, despite its potential importance, analysis of satellite cell motility or invasion quantitatively even in an in vitro setting can be difficult; one of the most powerful techniques for overcoming these difficulties is timelapse microscopy. Identification and longitudinal evaluation of individual cells over time permits not only quantification of variations in motility due to intrinsic or extrinsic factors, it permits observation and analysis of other (frequently unsuspected) cellular activities as well. We describe here three protocols developed in our group for quantitatively analyzing satellite cell motility over time in two dimensions on purified ECM substrates, in three dimensions on a living myofiber, and in three dimensions through an artificial matrix.

  14. Salamander limb regeneration involves the activation of a multipotent skeletal muscle satellite cell population.

    Science.gov (United States)

    Morrison, Jamie I; Lööf, Sara; He, Pingping; Simon, András

    2006-01-30

    In contrast to mammals, salamanders can regenerate complex structures after injury, including entire limbs. A central question is whether the generation of progenitor cells during limb regeneration and mammalian tissue repair occur via separate or overlapping mechanisms. Limb regeneration depends on the formation of a blastema, from which the new appendage develops. Dedifferentiation of stump tissues, such as skeletal muscle, precedes blastema formation, but it was not known whether dedifferentiation involves stem cell activation. We describe a multipotent Pax7+ satellite cell population located within the skeletal muscle of the salamander limb. We demonstrate that skeletal muscle dedifferentiation involves satellite cell activation and that these cells can contribute to new limb tissues. Activation of salamander satellite cells occurs in an analogous manner to how the mammalian myofiber mobilizes stem cells during skeletal muscle tissue repair. Thus, limb regeneration and mammalian tissue repair share common cellular and molecular programs. Our findings also identify satellite cells as potential targets in promoting mammalian blastema formation.

  15. Karyopherin Alpha 1 Regulates Satellite Cell Proliferation and Survival by Modulating Nuclear Import.

    Science.gov (United States)

    Choo, Hyo-Jung; Cutler, Alicia; Pavlath, Grace K

    2016-07-19

    Satellite cells are stem cells with an essential role in skeletal muscle repair. Precise regulation of gene expression is critical for proper satellite cell quiescence, proliferation, differentiation and self-renewal. Nuclear proteins required for gene expression are dependent on the nucleocytoplasmic transport machinery to access to nucleus, however little is known about regulation of nuclear transport in satellite cells. The best characterized nuclear import pathway is classical nuclear import which depends on a classical nuclear localization signal (cNLS) in a cargo protein and the heterodimeric import receptors, karyopherin alpha (KPNA) and beta (KPNB). Multiple KPNA1 paralogs exist and can differ in importing specific cNLS proteins required for cell differentiation and function. We show that transcripts for six Kpna paralogs underwent distinct changes in mouse satellite cells during muscle regeneration accompanied by changes in cNLS proteins in nuclei. Depletion of KPNA1, the most dramatically altered KPNA, caused satellite cells in uninjured muscle to prematurely activate, proliferate and undergo apoptosis leading to satellite cell exhaustion with age. Increased proliferation of satellite cells led to enhanced muscle regeneration at early stages of regeneration. In addition, we observed impaired nuclear localization of two key KPNA1 cargo proteins: p27, a cyclin-dependent kinase inhibitor associated with cell cycle control and lymphoid enhancer factor 1, a critical cotranscription factor for β-catenin. These results indicate that regulated nuclear import of proteins by KPNA1 is critical for satellite cell proliferation and survival and establish classical nuclear import as a novel regulatory mechanism for controlling satellite cell fate. Stem Cells 2016.

  16. Satellite-like cells contribute to pax7-dependent skeletal muscle repair in adult zebrafish.

    Science.gov (United States)

    Berberoglu, Michael A; Gallagher, Thomas L; Morrow, Zachary T; Talbot, Jared C; Hromowyk, Kimberly J; Tenente, Inês M; Langenau, David M; Amacher, Sharon L

    2017-04-15

    Satellite cells, also known as muscle stem cells, are responsible for skeletal muscle growth and repair in mammals. Pax7 and Pax3 transcription factors are established satellite cell markers required for muscle development and regeneration, and there is great interest in identifying additional factors that regulate satellite cell proliferation, differentiation, and/or skeletal muscle regeneration. Due to the powerful regenerative capacity of many zebrafish tissues, even in adults, we are exploring the regenerative potential of adult zebrafish skeletal muscle. Here, we show that adult zebrafish skeletal muscle contains cells similar to mammalian satellite cells. Adult zebrafish satellite-like cells have dense heterochromatin, express Pax7 and Pax3, proliferate in response to injury, and show peak myogenic responses 4-5 days post-injury (dpi). Furthermore, using a pax7a-driven GFP reporter, we present evidence implicating satellite-like cells as a possible source of new muscle. In lieu of central nucleation, which distinguishes regenerating myofibers in mammals, we describe several characteristics that robustly identify newly-forming myofibers from surrounding fibers in injured adult zebrafish muscle. These characteristics include partially overlapping expression in satellite-like cells and regenerating myofibers of two RNA-binding proteins Rbfox2 and Rbfoxl1, known to regulate embryonic muscle development and function. Finally, by analyzing pax7a; pax7b double mutant zebrafish, we show that Pax7 is required for adult skeletal muscle repair, as it is in the mouse.

  17. Comparison and analysis of Wuding and avian chicken skeletal muscle satellite cells.

    Science.gov (United States)

    Tong, H Q; Jiang, Z Q; Dou, T F; Li, Q H; Xu, Z Q; Liu, L X; Gu, D H; Rong, H; Huang, Y; Chen, X B; Jois, M; Te Pas, M F W; Ge, C R; Jia, J J

    2016-10-05

    Chicken skeletal muscle satellite cells are located between the basement membrane and the sarcolemma of mature muscle fibers. Avian broilers have been genetically selected based on their high growth velocity and large muscle mass. The Wuding chicken is a famous local chicken in Yunnan Province that undergoes non-selection breeding and is slow growing. In this study, we aimed to explore differences in the proliferation and differentiation properties of satellite cells isolated from the two chicken breeds. Using immunofluorescence, hematoxylin-eosin staining and real-time polymerase chain reaction analysis, we analyzed the in vitro characteristics of proliferating and differentiating satellite cells isolated from the two chicken breeds. The growth curve of satellite cells was S-shaped, and cells from Wuding chickens entered the logarithmic phase and plateau phase 1 day later than those from Avian chicken. The results also showed that the two skeletal muscle satellite cell lines were positive for Pax7, MyoD and IGF-1. The expression of Pax7 followed a downward trend, whereas that of MyoD and IGF-1 first increased and subsequently decreased in cells isolated from the two chickens. These data indicated that the skeletal muscle satellite cells of Avian chicken grow and differentiate faster than did those of Wuding chickens. We suggest that the methods of breeding selection applied to these breeds regulate the characteristics of skeletal muscle satellite cells to influence muscle growth.

  18. Phenotypic changes in satellite glial cells in cultured trigeminal ganglia.

    Science.gov (United States)

    Belzer, Vitali; Shraer, Nathanael; Hanani, Menachem

    2010-11-01

    Satellite glial cells (SGCs) are specialized cells that form a tight sheath around neurons in sensory ganglia. In recent years, there is increasing interest in SGCs and they have been studied in both intact ganglia and in tissue culture. Here we studied phenotypic changes in SGCs in cultured trigeminal ganglia from adult mice, containing both neurons and SGCs, using phase optics, immunohistochemistry and time-lapse photography. Cultures were followed for up to 14 days. After isolation virtually every sensory neuron is ensheathed by SGCs, as in the intact ganglia. After one day in culture, SGCs begin to migrate away from their parent neurons, but in most cases the neurons still retain an intact glial cover. At later times in culture, there is a massive migration of SGCs away from the neurons and they undergo clear morphological changes, and at 7 days they become spindle-shaped. At one day in culture SGCs express the glial marker glutamine synthetase, and also the purinergic receptor P2X7. From day 2 in culture the glutamine synthetase expression is greatly diminished, whereas that of P2X7 is largely unchanged. We conclude that SGCs retain most of their characteristics for about 24 h after culturing, but undergo major phenotypic changes at later times.

  19. Cripto regulates skeletal muscle regeneration and modulates satellite cell determination by antagonizing myostatin.

    Science.gov (United States)

    Guardiola, Ombretta; Lafuste, Peggy; Brunelli, Silvia; Iaconis, Salvatore; Touvier, Thierry; Mourikis, Philippos; De Bock, Katrien; Lonardo, Enza; Andolfi, Gennaro; Bouché, Ann; Liguori, Giovanna L; Shen, Michael M; Tajbakhsh, Shahragim; Cossu, Giulio; Carmeliet, Peter; Minchiotti, Gabriella

    2012-11-20

    Skeletal muscle regeneration mainly depends on satellite cells, a population of resident muscle stem cells. However, our understanding of the molecular mechanisms underlying satellite cell activation is still largely undefined. Here, we show that Cripto, a regulator of early embryogenesis, is a novel regulator of muscle regeneration and satellite cell progression toward the myogenic lineage. Conditional inactivation of cripto in adult satellite cells compromises skeletal muscle regeneration, whereas gain of function of Cripto accelerates regeneration, leading to muscle hypertrophy. Moreover, we provide evidence that Cripto modulates myogenic cell determination and promotes proliferation by antagonizing the TGF-β ligand myostatin. Our data provide unique insights into the molecular and cellular basis of Cripto activity in skeletal muscle regeneration and raise previously undescribed implications for stem cell biology and regenerative medicine.

  20. Straightforward synthesis of a novel ring-fused pyrazole-lactam and in vitro cytotoxic activity on cancer cell lines.

    Science.gov (United States)

    Bertuzzi, G; Locatelli, E; Colecchia, D; Calandro, P; Bonini, B F; Chandanshive, J Z; Mazzanti, A; Zani, P; Chiariello, M; Comes Franchini, M

    2016-07-19

    In this paper a straightforward synthesis of a novel pyrazole derivative is reported. Prominent feature of this synthetic process is a 1,3-Dipolar Cycloaddition of a suitable nitrile imine with an activated α,β-unsaturated lactam to afford directly and regioselectively the corresponding ring-fused pyrazole. Having obtained the central core of the synthetic target, a double stepwise functionalization with a "side chain" characterized by a terminal cyclic aliphatic amine was carried out. This molecular structure was designed to interact strongly with typical biological residues, and indeed it showed potent anticancer capability: in vitro cytotoxicity test on five different cancer cell lines showed interesting IC50 values in the range of 15-60 μM for exposure time of 24-72 h, thus resulting comparable with commercially available and nowadays therapeutically exploited anticancer compounds, such as 5-FU and NVP-BEZ235.

  1. The effect of temperature on proliferation and differentiation of chicken skeletal muscle satellite cells isolated from different muscle types.

    Science.gov (United States)

    Harding, Rachel L; Halevy, Orna; Yahav, Shlomo; Velleman, Sandra G

    2016-04-01

    Skeletal muscle satellite cells are a muscle stem cell population that mediate posthatch muscle growth and repair. Satellite cells respond differentially to environmental stimuli based upon their fiber-type of origin. The objective of this study was to determine how temperatures below and above the in vitro control of 38°C affected the proliferation and differentiation of satellite cells isolated from the chicken anaerobic pectoralis major (p. major) or mixed fiber biceps femoris (b.femoris) muscles. The satellite cells isolated from the p. major muscle were more sensitive to both cold and hot temperatures compared to the b.femoris satellite cells during both proliferation and differentiation. The expressions of myogenic regulatory transcription factors were also different between satellite cells from different fiber types. MyoD expression, which partially regulates proliferation, was generally expressed at higher levels in p. major satellite cells compared to the b.femoris satellite cells from 33 to 43°C during proliferation and differentiation. Similarly, myogenin expression, which is required for differentiation, was also expressed at higher levels in p. major satellite cells in response to both cold and hot temperatures during proliferation and differentiation than b. femoris satellite cells. These data demonstrate that satellite cells from the anaerobic p. major muscle are more sensitive than satellite cells from the aerobic b. femoris muscle to both hot and cold thermal stress during myogenic proliferation and differentiation.

  2. Bacterial and human cell mutagenicity study of some C[sub 18]H[sub 10] cyclopenta-fused polycyclic aromatic hydrocarbons associated with fossil fuels combustion

    Energy Technology Data Exchange (ETDEWEB)

    Lafleur, A.L.; Longwell, J.P.; Marr, J.A.; Monchamp, P.A.; Thilly, W.G. (Massachusetts Institute of Technology, Cambridge (United States)); Mulder, P.P.Y.; Boere, B.B.; Cornelisse, J.; Lugtenburg, J. (Univ. of Leiden (Netherlands))

    1993-06-01

    A number of isomeric C[sub 18]H[sub 10] polycyclic aromatic hydrocarbons (PAHs), thought to be primarily cyclopenta-fused PAHs, are produced during the combustion and pyrolysis of fossil fuels. To determine the importance of their contributions to the total mutagenic activity of combustion and pyrolysis samples in which they are found, we characterized reference quantities of four C[sub 18]H[sub 10] CP-PAHs: benzol [ghi] fluoranthene (BF), cyclopenta [cd] pyrene (CPP), cyclopent [hi] acephenanthrylene (CPAP), and cyclopent [hi] acaenthrylene (CPAA). Synthesis of CPAA and CPAP is described. The availability of reference samples of these isomers also proved to be an essential aid in the identification of the C[sub 18]H[sub 10] species often found in combustion and pyrolysis samples. Chemical analysis of selected combustion and pyrolysis samples showed that CPP was generally the most abundant C[sub 18]H[sub 10] isomer, followed by CPAP and BF. CPAA was detected only in pyrolysis products from pure PAHs. We tested the four C[sub 18]H[sub 10] PAHs for mutagenicity in a forward mutation assay using S. typhimurium. CPP, BF, and CPAA were roughly twice as mutagenic as benzo[a]pyrene (BaP), whereas CPAP was only slightly active. These PAHs were also tested for mutagenic activity in human cells. In this assay, CPP and CPAA were strongly mutagenic but less active than BaP, whereas CPAP and BF were inactive at the dose levels tested. Also, the bacterial and human cell mutagenicity of CPAA and CPAP were compared with the mutagenicity of their monocyclopenta-fused analogs, aceanthrylene and acephenanthrylene. Although the mutagenicities of CPAP and acephenanthrylene are similar, the mutagenic activity of CPAA is an order of magnitude greater than that of aceanthrylene.

  3. New insights into the epigenetic control of satellite cells

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Epigenetics finely tunes gene expression at a functionallevel without modifying the DNA sequence, therebycontributing to the complexity of genomic regulation.Satellite cells (SCs) are adult muscle stem cells thatare important for skeletal post-natal muscle growth,homeostasis and repair. The understanding of theepigenome of SCs at different stages and of themultiple layers of the post-transcriptional regulationof gene expression is constantly expanding. Dynamicinteractions between different epigenetic mechanismsregulate the appropriate timing of muscle-specific geneexpression and influence the lineage fate of SCs. Inthis review, we report and discuss the recent literatureabout the epigenetic control of SCs during the myogenicprocess from activation to proliferation and from theircommitment to a muscle cell fate to their differentiationand fusion to myotubes. We describe how the coordinatedactivities of the histone methyltransferasefamilies Polycomb group (PcG), which represses theexpression of developmentally regulated genes, andTrithorax group, which antagonizes the repressive activityof the PcG, regulate myogenesis by restricting geneexpression in a time-dependent manner during eachstep of the process. We discuss how histone acetylationand deacetylation occurs in specific loci throughoutSC differentiation to enable the time-dependent transcriptionof specific genes. Moreover, we describe themultiple roles of microRNA, an additional epigeneticmechanism, in regulating gene expression in SCs, byrepressing or enhancing gene transcription or translationduring each step of myogenesis. The importance ofthese epigenetic pathways in modulating SC activationand differentiation renders them as promising targetsfor disease interventions. Understanding the mostrecent findings regarding the epigenetic mechanismsthat regulate SC behavior is useful from the perspectiveof pharmacological manipulation for improving muscleregeneration and for promoting muscle homeostasisunder

  4. File list: Oth.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 TFs and others Muscle Satellite Cells, Skeletal... Muscle SRX818829,SRX818831,SRX818828,SRX818830 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  5. File list: His.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Histone Muscle Satellite Cells, Skeletal... Muscle SRX818827,SRX818825,SRX818826 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  6. File list: ALL.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 All antigens Muscle Satellite Cells, Skeletal...18833,SRX818834 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  7. File list: ALL.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 All antigens Muscle Satellite Cells, Skeletal...18834,SRX818832 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  8. File list: ALL.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 All antigens Muscle Satellite Cells, Skeletal...18830,SRX818832 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  9. File list: NoD.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 No description Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  10. File list: Unc.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Unclassified Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  11. File list: Pol.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 RNA polymerase Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  12. File list: DNS.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 DNase-seq Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  13. File list: Oth.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 TFs and others Muscle Satellite Cells, Skeletal... Muscle SRX818829,SRX818828,SRX818830,SRX818831 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  14. File list: NoD.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 No description Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  15. File list: Unc.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Unclassified Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  16. File list: Oth.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 TFs and others Muscle Satellite Cells, Skeletal... Muscle SRX818831,SRX818829,SRX818828,SRX818830 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  17. File list: NoD.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 No description Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  18. File list: InP.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Input control Muscle Satellite Cells, Skeletal... Muscle SRX818833,SRX818834,SRX818832 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  19. File list: His.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Histone Muscle Satellite Cells, Skeletal... Muscle SRX818827,SRX818825,SRX818826 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  20. File list: DNS.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 DNase-seq Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  1. File list: ALL.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available ALL.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 All antigens Muscle Satellite Cells, Skeletal...18832,SRX818833 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/ALL.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  2. File list: NoD.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available NoD.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 No description Muscle Satellite Cells, Skeletal... Muscle http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/NoD.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  3. File list: His.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Histone Muscle Satellite Cells, Skeletal... Muscle SRX818826,SRX818827,SRX818825 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  4. File list: InP.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Input control Muscle Satellite Cells, Skeletal Muscle... SRX818834,SRX818832,SRX818833 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  5. File list: Pol.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 RNA polymerase Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  6. File list: DNS.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 DNase-seq Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  7. File list: Pol.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 RNA polymerase Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  8. File list: Pol.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Pol.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 RNA polymerase Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Pol.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  9. File list: Unc.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Unclassified Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  10. File list: Oth.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Oth.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 TFs and others Muscle Satellite Cells, Skeletal Muscle... SRX818829,SRX818828,SRX818830,SRX818831 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Oth.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  11. File list: Unc.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available Unc.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Unclassified Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/Unc.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  12. File list: InP.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Input control Muscle Satellite Cells, Skeletal Muscle... SRX818832,SRX818833,SRX818834 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Myo.50.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  13. File list: InP.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Input control Muscle Satellite Cells, Skeletal Muscle... SRX818833,SRX818834,SRX818832 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Myo.05.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  14. File list: DNS.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available DNS.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 DNase-seq Muscle Satellite Cells, Skeletal Muscle... http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/DNS.Myo.20.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  15. File list: His.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available His.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle mm9 Histone Muscle Satellite Cells, Skeletal Muscle... SRX818827,SRX818826,SRX818825 http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/His.Myo.10.AllAg.Satellite_Cells,_Skeletal_Muscle.bed ...

  16. A simplified but robust method for the isolation of avian and mammalian muscle satellite cells

    Directory of Open Access Journals (Sweden)

    Baquero-Perez Belinda

    2012-06-01

    Full Text Available Abstract Background Current methods of isolation of muscle satellite cells from different animal species are highly variable making inter-species comparisons problematic. This variation mainly stems from the use of different proteolytic enzymes to release the satellite cells from the muscle tissue (sometimes a single enzyme is used but often a combination of enzymes is preferred and the different extracellular matrix proteins used to coat culture ware. In addition, isolation of satellite cells is frequently laborious and sometimes may require pre-plating of the cell preparation on uncoated flasks or Percoll centrifugation to remove contaminating fibroblasts. The methodology employed to isolate and culture satellite cells in vitro can critically determine the fusion of myoblasts into multi-nucleated myotubes. These terminally differentiated myotubes resemble mature myofibres in the muscle tissue in vivo, therefore optimal fusion is a keystone of in vitro muscle culture. Hence, a simple method of muscle satellite cell isolation and culture of different vertebrate species that can result in a high fusion rate is highly desirable. Results We demonstrate here a relatively simple and rapid method of isolating highly enriched muscle satellite cells from different avian and mammalian species. In brief, muscle tissue was mechanically dissociated, digested with a single enzyme (pronase, triturated with a 10-ml pipette, filtered and directly plated onto collagen coated flasks. Following this method and after optimization of the cell culture conditions, excellent fusion rates were achieved in the duck, chicken, horse and cow (with more than 50% cell fusion, and to a lesser extent pig, pointing to pronase as a highly suitable enzyme to release satellite cells from muscle tissue. Conclusions Our simplified method presents a quick and simple alternative to isolating highly enriched muscle satellite cell cultures which can subsequently rapidly differentiate

  17. The behaviour of satellite cells in response to exercise: what have we learned from human studies?

    DEFF Research Database (Denmark)

    Kadi, Fawzi; Olsen, Steen Schytte

    2005-01-01

    Understanding the complex role played by satellite cells in the adaptive response to exercise in human skeletal muscle has just begun. The development of reliable markers for the identification of satellite cell status (quiescence/activation/proliferation) is an important step towards the underst......Understanding the complex role played by satellite cells in the adaptive response to exercise in human skeletal muscle has just begun. The development of reliable markers for the identification of satellite cell status (quiescence/activation/proliferation) is an important step towards...... the understanding of satellite cell behaviour in exercised human muscles. It is hypothesised currently that exercise in humans can induce (1) the activation of satellite cells without proliferation, (2) proliferation and withdrawal from differentiation, (3) proliferation and differentiation to provide myonuclei...... and (4) proliferation and differentiation to generate new muscle fibres or to repair segmental fibre injuries. In humans, the satellite cell pool can increase as early as 4 days following a single bout of exercise and is maintained at higher level following several weeks of training. Cessation...

  18. Satellited 4q identified in amniotic fluid cells

    Energy Technology Data Exchange (ETDEWEB)

    Miller, I.; Hsieh, C.L.; Songster, G. [Stanford Univ. Medical Center, Stanford, CA (United States)] [and others

    1995-01-16

    Extra material was identified on the distal long arm of a chromosome 4 in an amniotic fluid specimen sampled at 16.6 weeks of gestational age. There was no visible loss of material from chromosome 4, and no evidence for a balanced rearrangement. The primary counseling issue in this case was advanced maternal age. Ultrasound findings were normal, and family history was unremarkable. The identical 4qs chromosome was observed in cells from a paternal peripheral blood specimen and appeared to be an unbalanced rearrangement. This extra material was NOR positive in lymphocytes from the father, but was negative in the fetal amniocytes. Father`s relatives were studied to verify the familial origin of this anomaly. In situ hybridization with both exon and intron sequences of ribosomal DNA demonstrated that ribosomal DNA is present at the terminus of the 4qs chromosome in the fetus, father, and paternal grandmother. This satellited 4q might have been derived from a translocation event that resulted in very little or no loss from the 4q and no specific phenotype. This derivative chromosome 4 has been inherited through at least 3 generations of phenotypically normal individuals. 8 refs., 3 figs.

  19. Satellite cell activity, without expansion, after nonhypertrophic stimuli.

    Science.gov (United States)

    Joanisse, Sophie; McKay, Bryon R; Nederveen, Joshua P; Scribbans, Trisha D; Gurd, Brendon J; Gillen, Jenna B; Gibala, Martin J; Tarnopolsky, Mark; Parise, Gianni

    2015-11-01

    The purpose of the present studies was to determine the effect of various nonhypertrophic exercise stimuli on satellite cell (SC) pool activity in human skeletal muscle. Previously untrained men and women (men: 29 ± 9 yr and women: 29 ± 2 yr, n = 7 each) completed 6 wk of very low-volume high-intensity sprint interval training. In a separate study, recreationally active men (n = 16) and women (n = 3) completed 6 wk of either traditional moderate-intensity continuous exercise (n = 9, 21 ± 4 yr) or low-volume sprint interval training (n = 10, 21 ± 2 yr). Muscle biopsies were obtained from the vastus lateralis before and after training. The fiber type-specific SC response to training was determined, as was the activity of the SC pool using immunofluorescent microscopy of muscle cross sections. Training did not induce hypertrophy, as assessed by muscle cross-sectional area, nor did the SC pool expand in any group. However, there was an increase in the number of active SCs after each intervention. Specifically, the number of activated (Pax7(+)/MyoD(+), P ≤ 0.05) and differentiating (Pax7(-)/MyoD(+), P ≤ 0.05) SCs increased after each training intervention. Here, we report evidence of activated and cycling SCs that may or may not contribute to exercise-induced adaptations while the SC pool remains constant after three nonhypertrophic exercise training protocols.

  20. Theoretical Investigation of Laser-Radiation Effects on Satellite Solar Cells

    Science.gov (United States)

    Abdel-Hadi, Yasser; El-Hameed, Afaf; Hamdy, Ola

    This research concerns with the studying of laser-powered solar panels for space applications. A model describing the laser effects on satellite solar cell has been developed. These effects are studied theoretically in order to determine the performance limits of the solar cells when they are powered by laser radiation during the satellite eclipse. A comparison between some different common types of the solar cells used for these purpose is considered in this study. The obtained results are reported to optimize the use of laser-powered satellites.

  1. Regulation of the muscle fiber microenvironment by activated satellite cells during hypertrophy.

    Science.gov (United States)

    Fry, Christopher S; Lee, Jonah D; Jackson, Janna R; Kirby, Tyler J; Stasko, Shawn A; Liu, Honglu; Dupont-Versteegden, Esther E; McCarthy, John J; Peterson, Charlotte A

    2014-04-01

    Our aim in the current study was to determine the necessity of satellite cells for long-term muscle growth and maintenance. We utilized a transgenic Pax7-DTA mouse model, allowing for the conditional depletion of > 90% of satellite cells with tamoxifen treatment. Synergist ablation surgery, where removal of synergist muscles places functional overload on the plantaris, was used to stimulate robust hypertrophy. Following 8 wk of overload, satellite cell-depleted muscle demonstrated an accumulation of extracellular matrix (ECM) and fibroblast expansion that resulted in reduced specific force of the plantaris. Although the early growth response was normal, an attenuation of hypertrophy measured by both muscle wet weight and fiber cross-sectional area occurred in satellite cell-depleted muscle. Isolated primary myogenic progenitor cells (MPCs) negatively regulated fibroblast ECM mRNA expression in vitro, suggesting a novel role for activated satellite cells/MPCs in muscle adaptation. These results provide evidence that satellite cells regulate the muscle environment during growth.

  2. Local NSAID infusion inhibits satellite cell proliferation in human skeletal muscle after eccentric exercise

    DEFF Research Database (Denmark)

    Mikkelsen, U R; Langberg, H; Helmark, I C

    2009-01-01

    exercise in vivo in human skeletal muscle. Eight young healthy males performed 200 maximal eccentric contractions with each leg. An NSAID was infused via a microdialysis catheter into the vastus lateralis muscle of one leg (NSAID leg) before, during, and for 4.5 h after exercise, with the other leg working...... of satellite cells 8 days after exercise. These results suggest that NSAIDs negatively affect satellite cell activity after unaccustomed eccentric exercise.......Despite the widespread consumption of nonsteroidal anti-inflammatory drugs (NSAIDs), the influence of these drugs on muscle satellite cells is not fully understood. The aim of the present study was to investigate the effect of a local NSAID infusion on satellite cells after unaccustomed eccentric...

  3. The quasi-parallel lives of satellite cells and atrophying muscle

    Directory of Open Access Journals (Sweden)

    Stefano eBiressi

    2015-07-01

    Full Text Available Skeletal muscle atrophy or wasting accompanies various chronic illnesses and the aging process, thereby reducing muscle function. One of the most important components contributing to effective muscle repair in postnatal organisms, the satellite cells, have recently become the focus of several studies examining factors participating in the atrophic process. We critically examine here the experimental evidence linking satellite cell function with muscle loss in connection with various diseases as well as aging, and in the subsequent recovery process. Several recent reports have investigated the changes in satellite cells in terms of their differentiation and proliferative capacity in response to various atrophic stimuli. In this regard, we review the molecular changes within satellite cells that contribute to their dysfunctional status in atrophy, with the intention of shedding light on novel potential pharmacological targets to counteract the loss of muscle mass.

  4. Gap junctional communication between the satellite cells of rat dorsal root ganglia.

    Science.gov (United States)

    Sakuma, E; Wang, H J; Asai, Y; Tamaki, D; Amano, K; Mabuchi, Y; Herbert, D C; Soji, T

    2001-06-01

    Many studies have described the ultrastructure of the dorsal root ganglia in various embryonic and adult animals, but in spite of the efforts of many investigators the functional role of the satellite cells in this tissue is not clearly understood. In this study, we discuss the function of this cell type based on the concept of cell-to-cell interaction through gap junctions. Five male 60 day-old Wistar strain rats were used. All animals were anesthetized with pentobarbital and perfused with glutaraldehyde fixative, then the dorsal root ganglia in levels L4, L5 and L6 were taken from each rat. After postosmication, the specimens were prepared for observation by transmission electron microscopy. All nerve cells were completely surrounded by satellite cell cytoplasmic expansions. The boundaries between adjacent nerve cells and satellite cells were complicated due to the presence of perikaryal projections of nerve cells. Gap junctions which showed the typical trilamellar structure of plasma membranes were found mainly between satellite cell processes belonging to the same nerve cell. On the other hand, some gap junctions were found between the satellite cell projections belonging to different nerve cells. The size of the gap junctions ranged from 300 to 400 nm. No gap junctions were associated with the plasma membrane of any nerve cell. In conclusion, only satellite cells can share free transcellular exchange of cytoplasmic molecules such as ions, amino acids, sugars and several second messengers including cAMP and inositol 1,4,5-triphosphate by way of gap junctions in dorsal root ganglia.

  5. Current advances in fused tetrathiafulvalene donor-acceptor systems.

    Science.gov (United States)

    Bergkamp, Jesse J; Decurtins, Silvio; Liu, Shi-Xia

    2015-02-21

    Electron donor (D) and acceptor (A) systems have been studied extensively. Among them, fused D-A systems have attracted much attention during the past decades. Herein, we will present the evolution of tetrathiafulvalene (TTF) fused D-A systems and their potential applications in areas such as solar cells, OFETs, molecular wires and optoelectronics just to name a few. The synthesis and electrochemical, photophysical and intrinsic properties of fused D-A systems will be described as well.

  6. Thiophene-rich fused-aromatic thienopyrazine acceptor for donor–acceptor low band-gap polymers for OTFT and polymer solar cell applications

    KAUST Repository

    Mondal, Rajib

    2010-01-01

    Thiophene enriched fused-aromatic thieno[3,4-b]pyrazine systems were designed and employed to produce low band gap polymers (Eg = 1.0-1.4 eV) when copolymerized with fluorene and cyclopentadithiophene. The copolymers are mainly investigated for organic thin film transistor and organic photovoltaic applications. Molecular packing in the thin films of these polymers was investigated using Grazing incidence X-ray Scattering. Although both fluorene and cyclopentadithiophene polymers follow similar face to face π-π stacking, the latter polymers show much smaller lamellar d-spacings due to side-chain interdigitation between the lamellae. This lead to the higher charge carrier mobilities in cyclopentadithiophene polymers (up to 0.044 cm2/V.s) compared to fluorene polymers (up to 8.1 × 10-3 cm2/V.s). Power conversion efficiency of 1.4% was achieved using fluorene copolymer in solar cells with a fullerene derivative as an acceptor. Although the cyclopentadithiophene polymers show lower band gaps with higher absorption coefficients compared to fluorene copolymers, but the power conversion efficiencies in solar cells of these polymers are low due to their low ionization potentials. © The Royal Society of Chemistry 2010.

  7. Reduced satellite cell population may lead to contractures in children with cerebral palsy.

    Science.gov (United States)

    Smith, Lucas R; Chambers, Henry G; Lieber, Richard L

    2013-03-01

    Satellite cells are the stem cells residing in muscle responsible for skeletal muscle growth and repair. Skeletal muscle in cerebral palsy (CP) has impaired longitudinal growth that results in muscle contractures. We hypothesized that the satellite cell population would be reduced in contractured muscle. We compared the satellite cell populations in hamstring muscles from participants with CP contracture (n=8; six males, two females; age range 6-15y; Gross Motor Function Classification System [GMFCS] levels II-V; 4 with hemiplegia, 4 with diplegia) and from typically developing participants (n=8; six males, two females, age range 15-18y). Muscle biopsies were extracted from the gracilis and semitendinosus muscles and mononuclear cells were isolated. Cell surface markers were stained with fluorescently conjugated antibodies to label satellite cells (neural cell adhesion molecule) and inflammatory and endothelial cells (CD34 and CD4 respectively). Cells were analyzed using flow cytometry to determine cell populations. After gating for intact cells a mean of 12.8% (SD 2.8%) were determined to be satellite cells in typically developing children, but only 5.3% (SD 2.3%; p0.05) suggesting the isolation procedure was valid. A reduced satellite cell population may account for the decreased longitudinal growth of muscles in CP that develop into fixed contractures or the decreased ability to strengthen muscle in CP. This suggests a unique musculoskeletal disease mechanism and provides a potential therapeutic target for debilitating muscle contractures. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

  8. mTOR is necessary for proper satellite cell activity and skeletal muscle regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Pengpeng [Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry & Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Department of Animal Sciences, Purdue University, West Lafayette, IN 47907 (United States); Liang, Xinrong; Shan, Tizhong [Department of Animal Sciences, Purdue University, West Lafayette, IN 47907 (United States); Jiang, Qinyang [Department of Animal Sciences, Purdue University, West Lafayette, IN 47907 (United States); College of Animal Science and Technology, Guangxi University, Nanning 530004 (China); Deng, Changyan [Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry & Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Zheng, Rong, E-mail: zhengrong@mail.hzau.edu.cn [Key Laboratory of Swine Genetics and Breeding of Agricultural Ministry & Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan 430070 (China); Kuang, Shihuan, E-mail: skuang@purdue.edu [Department of Animal Sciences, Purdue University, West Lafayette, IN 47907 (United States)

    2015-07-17

    The serine/threonine kinase mammalian target of rapamycin (mTOR) is a key regulator of protein synthesis, cell proliferation and energy metabolism. As constitutive deletion of Mtor gene results in embryonic lethality, the function of mTOR in muscle stem cells (satellite cells) and skeletal muscle regeneration remains to be determined. In this study, we established a satellite cell specific Mtor conditional knockout (cKO) mouse model by crossing Pax7{sup CreER} and Mtor{sup flox/flox} mice. Skeletal muscle regeneration after injury was severely compromised in the absence of Mtor, indicated by increased number of necrotic myofibers infiltrated by Evans blue dye, and reduced number and size of regenerated myofibers in the Mtor cKO mice compared to wild type (WT) littermates. To dissect the cellular mechanism, we analyzed satellite cell-derived primary myoblasts grown on single myofibers or adhered to culture plates. The Mtor cKO myoblasts exhibited defective proliferation and differentiation kinetics when compared to myoblasts derived from WT littermates. At the mRNA and protein levels, the Mtor cKO myoblasts expressed lower levels of key myogenic determinant genes Pax7, Myf5, Myod, Myog than did the WT myoblasts. These results suggest that mTOR is essential for satellite cell function and skeletal muscle regeneration through controlling the expression of myogenic genes. - Highlights: • Pax7{sup CreER} was used to delete Mtor gene in satellite cells. • Satellite cell specific deletion of Mtor impairs muscle regeneration. • mTOR is necessary for satellite cell proliferation and differentiation. • Deletion of Mtor leads to reduced expression of key myogenic genes.

  9. Conditional Cripto overexpression in satellite cells promotes myogenic commitment and enhances early regeneration.

    Science.gov (United States)

    Prezioso, Carolina; Iaconis, Salvatore; Andolfi, Gennaro; Zentilin, Lorena; Iavarone, Francescopaolo; Guardiola, Ombretta; Minchiotti, Gabriella

    2015-01-01

    Skeletal muscle regeneration mainly depends on satellite cells, a population of resident muscle stem cells. Despite extensive studies, knowledge of the molecular mechanisms underlying the early events associated with satellite cell activation and myogenic commitment in muscle regeneration remains still incomplete. Cripto is a novel regulator of postnatal skeletal muscle regeneration and a promising target for future therapy. Indeed, Cripto is expressed both in myogenic and inflammatory cells in skeletal muscle after acute injury and it is required in the satellite cell compartment to achieve effective muscle regeneration. A critical requirement to further explore the in vivo cellular contribution of Cripto in regulating skeletal muscle regeneration is the possibility to overexpress Cripto in its endogenous configuration and in a cell and time-specific manner. Here we report the generation and the functional characterization of a novel mouse model for conditional expression of Cripto, i.e., the Tg:DsRed (loxP/loxP) Cripto-eGFP mice. Moreover, by using a satellite cell specific Cre-driver line we investigated the biological effect of Cripto overexpression in vivo, and provided evidence that overexpression of Cripto in the adult satellite cell compartment promotes myogenic commitment and differentiation, and enhances early regeneration in a mouse model of acute injury.

  10. Function of Membrane-Associated Proteoglycans in the Regulation of Satellite Cell Growth.

    Science.gov (United States)

    Song, Yan

    2016-01-01

    Muscle growth can be divided into embryonic and postnatal periods. During the embryonic period, mesenchymal stem cells proliferate and differentiate to form muscle fibers. Postnatal muscle growth (hypertrophy) is characterized by the enlargement of existing muscle fiber size. Satellite cells (also known as adult myoblasts) are responsible for hypertrophy. The activity of satellite cells can be regulated by their extracellular matrix (ECM). The ECM is composed of collagens, proteoglycans, non-collagenous glycoproteins, cytokines and growth factors. Proteoglycans contain a central core protein with covalently attached glycosaminoglycans (GAGs: chondroitin sulfate, keratan sulfate, dermatan sulfate, and heparan sulfate) and N- or O-linked glycosylation chains. Membrane-associated proteoglycans attach to the cell membrane either through a glycosylphosphatidylinositol anchor or transmembrane domain. The GAGs can bind proteins including cytokines and growth factors. Both cytokines and growth factors play important roles in regulating satellite cell growth and development. Cytokines are generally associated with immune cells. However, cytokines can also affect muscle cell development. For instance, interleukin-6, tumor necrosis factor-α, and leukemia inhibitory factor have been reported to affect the proliferation and differentiation of satellite cells and myoblasts. Growth factors are potent stimulators or inhibitors of satellite cell proliferation and differentiation. The proper function of some cytokines and growth factors requires an interaction with the cell membrane-associated proteoglycans to enhance the affinity to bind to their primary receptors to initiate downstream signal transduction. This chapter is focused on the interaction of membrane-associated proteoglycans with cytokines and growth factors, and their role in satellite cell growth and development.

  11. Development of an enhanced bovine viral diarrhea virus subunit vaccine based on E2 glycoprotein fused to a single chain antibody which targets to antigen-presenting cells.

    Science.gov (United States)

    Pecora, Andrea; Malacari, Darío A; Pérez Aguirreburualde, María S; Bellido, Demian; Escribano, José M; Dus Santos, María J; Wigdorovitz, Andrés

    2015-01-01

    Bovine viral diarrhea virus (BVDV) is an important cause of economic losses worldwide. E2 is an immunodominant protein and a promising candidate to develop subunit vaccines. To improve its immunogenicity, a truncated E2 (tE2) was fused to a single chain antibody named APCH, which targets to antigen-presenting cells. APCH-tE2 and tE2 proteins were expressed in the baculovirus system and their immunogenicity was firstly compared in guinea pigs. APCH-tE2 vaccine was the best one to evoke a humoral response, and for this reason, it was selected for a cattle vaccination experiment. All the bovines immunized with 1.5 μg of APCH-tE2 developed high levels of neutralizing antibodies against BVDV up to a year post-immunization, demonstrating its significant potential as a subunit vaccine. This novel vaccine is undergoing scale-up and was transferred to the private sector. Nowadays, it is being evaluated for registration as the first Argentinean subunit vaccine for cattle. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  12. Raman spectroscopic measurements of CO2 density: Experimental calibration with high-pressure optical cell (HPOC) and fused silica capillary capsule (FSCC) with application to fluid inclusion observations

    Science.gov (United States)

    Wang, X.; Chou, I.-Ming; Hu, W.; Burruss, R.C.; Sun, Q.; Song, Y.

    2011-01-01

    Raman spectroscopy is a powerful method for the determination of CO2 densities in fluid inclusions, especially for those with small size and/or low fluid density. The relationship between CO2 Fermi diad split (??, cm-1) and CO2 density (??, g/cm3) has been documented by several previous studies. However, significant discrepancies exist among these studies mainly because of inconsistent calibration procedures and lack of measurements for CO2 fluids having densities between 0.21 and 0.75g/cm3, where liquid and vapor phases coexist near room temperature.In this study, a high-pressure optical cell and fused silica capillary capsules were used to prepare pure CO2 samples with densities between 0.0472 and 1.0060g/cm3. The measured CO2 Fermi diad splits were calibrated with two well established Raman bands of benzonitrile at 1192.6 and 1598.9cm-1. The relationship between the CO2 Fermi diad split and density can be represented by: ??=47513.64243-1374.824414????+13.25586152????2-0.04258891551????3 (r2=0.99835, ??=0.0253g/cm3), and this relationship was tested by synthetic fluid inclusions and natural CO2-rich fluid inclusions. The effects of temperature and the presence of H2O and CH4 on this relationship were also examined. ?? 2011 Elsevier Ltd.

  13. Proton irradiation effects of amorphous silicon solar cell for solar power satellite

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Yousuke; Oshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Sasaki, Susumu; Kuroda, Hideo; Ushirokawa, Akio

    1997-03-01

    Flexible amorphous silicon(fa-Si) solar cell module, a thin film type, is regarded as a realistic power generator for solar power satellite. The radiation resistance of fa-Si cells was investigated by the irradiations of 3,4 and 10 MeV protons. The hydrogen gas treatment of the irradiated fa-Si cells was also studied. The fa-Si cell shows high radiation resistance for proton irradiations, compared with a crystalline silicon solar cell. (author)

  14. Human cancer cell line based approach of 1,3,4-thiadiazole and its fused ring: A comprehensive review.

    Science.gov (United States)

    Raj, Vinit; Rai, Amit; Saha, Sudipta

    2016-10-13

    The chemistry of heterocyclic containing, 1,3,4-thiadiazole has been an interesting field of study from ancient years. Subsequently, 1,3,4-thiadiazole nucleus constitutes a significant class of compounds for new drug development. Recently, various 1,3,4-thiadiazole derivatives have been synthesized and evaluated their biological activities including antimicrobial, antituberculosis, antioxidant, anti-inflammatory, anticonvulsants, antidepressant and anxiolytic, antihypertensive, anticancer and antifungal activity. The search for anticancer compounds with more selective activity and lower side effect continue to be an active area of argument examination in medicinal chemistry. This review is elaborately described the medicinal chemistry, their structural activity relationship and anticancer properties with respect to human cell line based approach related to synthesized 1,3,4-thiadiazole derivatives.

  15. Temperature effect on proliferation and differentiation of satellite cells from turkeys with different growth rates.

    Science.gov (United States)

    Clark, D L; Coy, C S; Strasburg, G M; Reed, K M; Velleman, S G

    2016-04-01

    Poultry selected for growth have an inefficient thermoregulatory system and are more sensitive to temperature extremes. Satellite cells are precursors to skeletal muscle and mediate all posthatch muscle growth. Their physiological functions are affected by temperature. The objective of the current study was to determine how temperature affects satellite cells isolated from the pectoralis major (p. major) muscle (breast muscle) of turkeys selected for increased 16 wk body weight (F line) in comparison to a randombred control line (RBC2) from which the F line originated. Pectoralis major muscle satellite cells were thermally challenged by culturing between 33°C and 43°C to analyze the effects of cold and heat on proliferation and differentiation as compared to control temperature of 38°C. Expression levels of myogenic regulatory factors: myogenic differentiation factor 1 (MYOD1) and myogenin (MYOG) were quantified by quantitative polymerase chain reaction (qPCR). At all sampling times, proliferation increased at a linear rate across temperature in both the RBC2 and F lines. Differentiation also increased at a linear rate across temperature from 33 to 41°C at all sampling times in both the F and RBC2 lines. Satellite cells isolated from F line turkeys were more sensitive to both hot and cold temperatures as proliferation and differentiation increased to a greater extent across temperature (33 to 43°C) when compared with the RBC2 line. Expression of MYOD1 and MYOG increased as temperatures increased from 33 to 41°C at all sampling times in both the F and RBC2 lines. These results demonstrate that satellite cell function is sensitive to both cold and hot temperatures and p. major muscle satellite cells from F line turkeys are more sensitive to temperature extremes than RBC2 satellite cells.

  16. Sphingosine-1-phosphate mediates epidermal growth factor-induced muscle satellite cell activation

    Energy Technology Data Exchange (ETDEWEB)

    Nagata, Yosuke, E-mail: cynagata@mail.ecc.u-tokyo.ac.jp; Ohashi, Kazuya; Wada, Eiji; Yuasa, Yuki; Shiozuka, Masataka; Nonomura, Yoshiaki; Matsuda, Ryoichi

    2014-08-01

    Skeletal muscle can regenerate repeatedly due to the presence of resident stem cells, called satellite cells. Because satellite cells are usually quiescent, they must be activated before participating in muscle regeneration in response to stimuli such as injury, overloading, and stretch. Although satellite cell activation is a crucial step in muscle regeneration, little is known of the molecular mechanisms controlling this process. Recent work showed that the bioactive lipid sphingosine-1-phosphate (S1P) plays crucial roles in the activation, proliferation, and differentiation of muscle satellite cells. We investigated the role of growth factors in S1P-mediated satellite cell activation. We found that epidermal growth factor (EGF) in combination with insulin induced proliferation of quiescent undifferentiated mouse myoblast C2C12 cells, which are also known as reserve cells, in serum-free conditions. Sphingosine kinase activity increased when reserve cells were stimulated with EGF. Treatment of reserve cells with the D-erythro-N,N-dimethylsphingosine, Sphingosine Kinase Inhibitor, or siRNA duplexes specific for sphingosine kinase 1, suppressed EGF-induced C2C12 activation. We also present the evidence showing the S1P receptor S1P2 is involved in EGF-induced reserve cell activation. Moreover, we demonstrated a combination of insulin and EGF promoted activation of satellite cells on single myofibers in a manner dependent on SPHK and S1P2. Taken together, our observations show that EGF-induced satellite cell activation is mediated by S1P and its receptor. - Highlights: • EGF in combination with insulin induces proliferation of quiescent C2C12 cells. • Sphingosine kinase activity increases when reserve cells are stimulated with EGF. • EGF-induced activation of reserve cells is dependent on sphingosine kinase and ERK. • The S1P receptor S1P2 is involved in EGF-induced reserve cell activation. • EGF-induced reserve cell activation is mediated by S1P and its

  17. Influence of skeletal muscle satellite cells implanted into infarcted myocardium on remnant myocyte volumes

    Institute of Scientific and Technical Information of China (English)

    钟竑; 朱洪生; 卫洪超; 张臻

    2003-01-01

    Objective To study the effects of skeletal muscle satellite cells implanted into infarcted myocardium on the volume of remnant myocytes.Methods Thirty-six adult mongrel canines were divided randomly into implantation group and control group. In the implantation group, skeletal muscle satellite cells taken from the gluteus maximus muscles of the dogs were cultured, proliferated and labeled with 4', 6-diamidino-2-phenylindone (DAPI) in vitro. In both groups, a model of acute myocardial infarction was established in every dog. In the implantation group, each dog was injected with M199 solution containing autologous skeletal muscle satellite cells. The dogs in the control group received M199 solution without skeletal muscle satellite cells. The dogs of both groups were killed 2, 4 and 8 weeks after implantation (six dogs in a separate group each time). Both infarcted myocardium and normal myocytes distal from the infracted regions isolated were observed under optical and fluorescent microscope. Their volumes were determined using a confocal microscopy image analysis system and analyzed using SAS. A P<0.05 was considered significant.Results A portion of the implanted cells differentiated into muscle fiber with striations and were connected with intercalated discs. Cross-sectional area and cell volume were increased in normal myocardium. Hypertrophy of remnant myocytes in the infarcted site after skeletal muscle cell implantation was much more evident than in the control group. Cross-sectional area, cell area and cell volume differed significantly from those of the control group (P< 0.05). Hypertrophy of the cells occurred predominantly in terms of width and thickness, whereas cell length remained unchanged. Conclusion Skeletal muscle satellite cells implanted into infarct myocardium, could induce the hypertrophy of remnant myocyte cells in the infarcted site and could also aid in the recovery of the contractile force of the infarcted myocardium.

  18. Enhanced satellite cell proliferation with resistance training in elderly men and women

    DEFF Research Database (Denmark)

    Mackey, Abigail; Esmarck, B; Kadi, F

    2007-01-01

    In addition to the well-documented loss of muscle mass and strength associated with aging, there is evidence for the attenuating effects of aging on the number of satellite cells in human skeletal muscle. The aim of this study was to investigate the response of satellite cells in elderly men...... and women to 12 weeks of resistance training. Biopsies were collected from the m. vastus lateralis of 13 healthy elderly men and 16 healthy elderly women (mean age 76+/-SD 3 years) before and after the training period. Satellite cells were visualized by immunohistochemical staining of muscle cross......-sections with a monoclonal antibody against neural cell adhesion molecule (NCAM) and counterstaining with Mayer's hematoxylin. Compared with the pre-training values, there was a significant increase (Pcells per fiber post-training in males (from 0.11+/-0.03 to 0...

  19. THE ROLE OF SATELLITE CELLS IN CRUSH INJURY OF RAT SKELETON MUSCLE

    Directory of Open Access Journals (Sweden)

    DilekBURUKOĞLU

    2013-02-01

    Full Text Available The crush type of injury in rat skeletal muscle is often used in tissue degeneration and regeneration. After crush injury muscle tissue begins to regenerate. In this process, it is accepted that satellite cells play an important role which are very sensitive to muscle injury. The aim of this microscopic study was to examine role of satellite cells in muscle regeneration in crush injury. This research was done the department of Histology&Embryology in Eskişehir Osmangazi University in 2008. Ethic approval of this study has been received. During the study, the whole essential and ethics conditionshave been done. In the study 36 Spraque-Dawley rats were used. The rats were separated into 5 groups as test and control groups. Crush type of injury has been applied on muscles of right hind extremitiesof testing group rats by applying 3.5 kg of weight for 6 hours. In according to testing periods rats were anaesthetized intraperitoneally with ketamine 30mg/kg + xylazine 10mg/kg and sacrificied 3, 7, 14 and 21-day intervals. After crush injury, increased satellite cells were particularly observed on day 7. Alsosignificant increased of satellite cells and regenerated myofibrils were detected on day 14. However, satellite cells were seen on day-21 were similar to control group. In crush injuries, number of satellitecells were markedly increased and actively involved into regeneration process of the skeleton muscle.

  20. Characterisation of equine satellite cell transcriptomic profile response to β-hydroxy-β-methylbutyrate (HMB).

    Science.gov (United States)

    Szcześniak, Katarzyna A; Ciecierska, Anna; Ostaszewski, Piotr; Sadkowski, Tomasz

    2016-10-01

    β-Hydroxy-β-methylbutyrate (HMB) is a popular ergogenic aid used by human athletes and as a supplement to sport horses, because of its ability to aid muscle recovery, improve performance and body composition. Recent findings suggest that HMB may stimulate satellite cells and affect expressions of genes regulating skeletal muscle cell growth. Despite the scientific data showing benefits of HMB supplementation in horses, no previous study has explained the mechanism of action of HMB in this species. The aim of this study was to reveal the molecular background of HMB action on equine skeletal muscle by investigating the transcriptomic profile changes induced by HMB in equine satellite cells in vitro. Upon isolation from the semitendinosus muscle, equine satellite cells were cultured until the 2nd day of differentiation. Differentiating cells were incubated with HMB for 24 h. Total cellular RNA was isolated, amplified, labelled and hybridised to microarray slides. Microarray data validation was performed with real-time quantitative PCR. HMB induced differential expressions of 361 genes. Functional analysis revealed that the main biological processes influenced by HMB in equine satellite cells were related to muscle organ development, protein metabolism, energy homoeostasis and lipid metabolism. In conclusion, this study demonstrated for the first time that HMB has the potential to influence equine satellite cells by controlling global gene expression. Genes and biological processes targeted by HMB in equine satellite cells may support HMB utility in improving growth and regeneration of equine skeletal muscle; however, the overall role of HMB in horses remains equivocal and requires further proteomic, biochemical and pharmacokinetic studies.

  1. Restricted maternal nutrition alters myogenic regulatory factor expression in satellite cells of ovine offspring.

    Science.gov (United States)

    Raja, J S; Hoffman, M L; Govoni, K E; Zinn, S A; Reed, S A

    2016-07-01

    Poor maternal nutrition inhibits muscle development and postnatal muscle growth. Satellite cells are myogenic precursor cells that contribute to postnatal muscle growth, and their activity can be evaluated by the expression of several transcription factors. Paired-box (Pax)7 is expressed in quiescent and active satellite cells. MyoD is expressed in activated and proliferating satellite cells and myogenin is expressed in terminally differentiating cells. Disruption in the expression pattern or timing of expression of myogenic regulatory factors negatively affects muscle development and growth. We hypothesized that poor maternal nutrition during gestation would alter the in vitro temporal expression of MyoD and myogenin in satellite cells from offspring at birth and 3 months of age. Ewes were fed 100% or 60% of NRC requirements from day 31±1.3 of gestation. Lambs from control-fed (CON) or restricted-fed (RES) ewes were euthanized within 24 h of birth (birth; n=5) or were fed a control diet until 3 months of age (n=5). Satellite cells isolated from the semitendinosus muscle were used for gene expression analysis or cultured for 24, 48 or 72 h and immunostained for Pax7, MyoD or myogenin. Fusion index was calculated from a subset of cells allowed to differentiate. Compared with CON, temporal expression of MyoD and myogenin was altered in cultured satellite cells isolated from RES lambs at birth. The percent of cells expressing MyoD was greater in RES than CON (P=0.03) after 24 h in culture. After 48 h of culture, there was a greater percent of cells expressing myogenin in RES compared with CON (P0.05). In satellite cells from RES lambs at 3 months of age, the percent of cells expressing MyoD and myogenin were greater than CON after 72 h in culture (Psatellite cells of the offspring, which may reduce the pool of myoblasts, decrease myoblast fusion and contribute to the poor postnatal muscle growth previously observed in these animals.

  2. Fused aromatic thienopyrazines: structure, properties and function

    KAUST Repository

    Mondal, Rajib

    2010-01-01

    Recent development of a fused aromatic thieno[3.4-b]pyrazine system and their application in optoelectronic devices are reviewed. Introduction of a fused aromatic unit followed by side chain engineering, dramatically enhanced the charge carrier mobility in thin film transistor devices and mobilities up to 0.2 cm2/Vs were achieved. The optoelectronic properties of these fused aromatic thienopyrazine polymers (Eg = 1.3 to 1.6 eV, HOMO = -4.9 to -5.2 V) were tuned by introduction of various fused aromatic rings within thienopyrazine. By balancing the fundamental properties of these polymers, both high charge carrier mobilities and moderate PCEs in solar cells were achieved. Further, effects of copolymerizing units are discussed. Low band gap semiconducting polymer (Eg ∼ 1 eV) with high field effect mobility (0.044 cm2/Vs) was obtained using cyclopentadithiophene as copolymerizing unit. Finally, a molecular design approach to enhance the absorption coefficients is discussed, which resulted in improved power conversion efficiency in bulk heterojunction solar cells. © 2010 The Royal Society of Chemistry.

  3. IMPROVING METHODOLOGICAL STRATEGIES FOR SATELLITE CELLS COUNTING IN HUMAN MUSCLE DURING AGEING

    Directory of Open Access Journals (Sweden)

    Špela Sajko

    2011-05-01

    Full Text Available Stereological methods, based on the optical disector principle and fluorescent staining, were developed for estimating frequency of satellite cells in skeletal muscles. The parameter NL(sc, fib (number of satellite cells per fibre length was compared with the parameter NN(sc, nucl (the percentage of satellite cell nuclei in all muscle nuclei, most often published in the literature, by applying unbiased sampling and counting procedures and using a confocal microscope. The methods were tested in autopsy samples of four young vs. four old human vastus lateralis muscles. Both parameters NL(sc, fib and NN(sc, nucl declined during ageing. However, it appears that the two parameters cannot be substituted one by the other because the number of nuclei per fibre length tends to be increased during aging. Using the introduced methods, it is more straightforward to estimate NL(sc, fib than NN(sc, nucl.

  4. Pericytes in the myovascular niche promote post-natal myofiber growth and satellite cell quiescence.

    Science.gov (United States)

    Kostallari, Enis; Baba-Amer, Yasmine; Alonso-Martin, Sonia; Ngoh, Pamela; Relaix, Frederic; Lafuste, Peggy; Gherardi, Romain K

    2015-04-01

    The satellite cells, which serve as adult muscle stem cells, are both located beneath myofiber basement membranes and closely associated with capillary endothelial cells. We observed that 90% of capillaries were associated with pericytes in adult mouse and human muscle. During post-natal growth, newly formed vessels with their neuroglial 2 proteoglycan (NG2)-positive pericytes became progressively associated with the post-natal muscle stem cells, as myofibers increased in size and satellite cells entered into quiescence. In vitro, human muscle-derived pericytes promoted myogenic cell differentiation through insulin-like growth factor 1 (IGF1) and myogenic cell quiescence through angiopoietin 1 (ANGPT1). Diphtheria toxin-induced ablation of muscle pericytes in growing mice led both to myofiber hypotrophy and to impaired establishment of stem cells quiescence. Similar effects were observed following conditional in vivo deletion of pericyte Igf1 and Angpt1 genes, respectively. Our data therefore demonstrate that, by promoting post-natal myogenesis and stem cell quiescence, pericytes play a key role in the microvascular niche of satellite cells. © 2015. Published by The Company of Biologists Ltd.

  5. THE IMPROVEMENT OF INFARCTED MYOCARDIAL CONTRACTILE FORCE AFTER AUTOLOGOUS SKELETAL MUSCLE SATELLITE CELL IMPLANTATION

    Institute of Scientific and Technical Information of China (English)

    钟竑; 朱洪生; 张臻

    2002-01-01

    Objective To study the improvement of infarcted myocardial contractile force after autologous skeletal muscle satellite cell implantation via intracoronary arterial perfusion. Methods Skeletal muscle cells were harvested from gluteus max of adult mongrel dogs and the cells were cultured and expanded before being labeled with DAPI (4, 6-diamidino-2-phenylindone). The labeled cells were then implanted into the acute myocardial infarct site via the ligated left anterior descending (LAD) coronary artery. Specimens were taken at 2nd, 4th, 8th week after myoblast implantation for histologic and contractile force evaluation, respectively. Results The satellite cells with fluorescence had been observed in the infarct site and also in papi-llary muscle with consistent oriented direction of host myocardium. A portion of the implanted cells had differen-tiated into muscle fibers. Two weeks after implantation, the myocardial contractile force showed no significant difference between the cell implant group and control group. At 4 and 8 week, the contractile force in the cell implant group was better than that in control group. Conclusion The skeletal muscle satellite cells, implanted into infarct myocardium by intracoronary arterial perfusion, could disseminate through the entire infarcted zone with myocardial regeneration and improve the contractile function of the infarcted myocardium.

  6. Changes in satellite cells in human skeletal muscle after a single bout of high intensity exercise

    DEFF Research Database (Denmark)

    Crameri, Regina M; Langberg, Henning; Magnusson, Peter

    2004-01-01

    desmin or dystrophin, were not observed, and hence did not appear to induce the expression of either N-CAM or FA1. We therefore propose that satellite cells can be induced to re-enter the cell growth cycle after a single bout of unaccustomed high intensity exercise. However, a single bout of exercise......No studies to date have reported activation of satellite cells in vivo in human muscle after a single bout of high intensity exercise. In this investigation, eight individuals performed a single bout of high intensity exercise with one leg, the contralateral leg being the control. A significant...... increase in mononuclear cells staining for the neural cell adhesion molecule (N-CAM) and fetal antigen 1 (FA1) were observed within the exercised human vastus lateralis muscle on days 4 and 8 post exercise. In addition, a significant increase in the concentration of the FA1 protein was determined...

  7. Intracellular distribution, cell-to-cell trafficking and tubule-inducing activity of the 50 kDa movement protein of Apple chlorotic leaf spot virus fused to green fluorescent protein.

    Science.gov (United States)

    Satoh, H; Matsuda, H; Kawamura, T; Isogai, M; Yoshikawa, N; Takahashi, T

    2000-08-01

    The 50 kDa protein (50KP) encoded by ORF2 of Apple chlorotic leaf spot virus (ACLSV) fused to green fluorescent protein (GFP) was expressed transiently in cells of Nicotiana occidentalis and Chenopodium quinoa leaves. Its intracellular distribution, cell-to-cell trafficking in leaf epidermis and tubule formation on the surface of protoplasts were analysed. The 50KP-GFP fluorescence was distributed as small irregular spots or a fibrous network structure on the periphery of epidermal cells and protoplasts of both plant species. In leaf epidermis of N. occidentalis, the protein spread from the cells that produced it into neighbouring cells in both young and mature leaves and targetted plasmodesmata in these cells. In contrast, GFP was restricted to single cells in most cases in mature leaves. When 50KP and GFP were co-expressed in leaf epidermis of N. occidentalis, GFP spread more widely from the initial cells that produced it than when GFP was expressed alone, suggesting that 50KP facilitated the cell-to-cell trafficking of GFP. 50KP-GFP was able to complement local spread of 50KP-deficient virus when expressed transiently in leaf epidermis of C. quinoa. Expression of 50KP-GFP in protoplasts resulted in the production of tubular structures protruding from the surface. Mutational analyses showed that the C-terminal region (aa 287-457) was not essential for localization to plasmodesmata, cell-to-cell trafficking, complementation of movement of 50KP-deficient virus or tubule formation on protoplasts. In contrast, deletions in the N-terminal region resulted in the complete disruption of all these activities.

  8. Pax3-induced expansion enables the genetic correction of dystrophic satellite cells.

    Science.gov (United States)

    Filareto, Antonio; Rinaldi, Fabrizio; Arpke, Robert W; Darabi, Radbod; Belanto, Joseph J; Toso, Erik A; Miller, Auston Z; Ervasti, James M; McIvor, R Scott; Kyba, Michael; Perlingeiro, Rita Cr

    2015-01-01

    Satellite cells (SCs) are indispensable for muscle regeneration and repair; however, due to low frequency in primary muscle and loss of engraftment potential after ex vivo expansion, their use in cell therapy is currently unfeasible. To date, an alternative to this limitation has been the transplantation of SC-derived myogenic progenitor cells (MPCs), although these do not hold the same attractive properties of stem cells, such as self-renewal and long-term regenerative potential. We develop a method to expand wild-type and dystrophic fresh isolated satellite cells using transient expression of Pax3. This approach can be combined with genetic correction of dystrophic satellite cells and utilized to promote muscle regeneration when transplanted into dystrophic mice. Here, we show that SCs from wild-type and dystrophic mice can be expanded in culture through transient expression of Pax3, and these expanded activated SCs can regenerate the muscle. We test this approach in a gene therapy model by correcting dystrophic SCs from a mouse lacking dystrophin using a Sleeping Beauty transposon carrying the human μDYSTROPHIN gene. Transplantation of these expanded corrected cells into immune-deficient, dystrophin-deficient mice generated large numbers of dystrophin-expressing myofibers and improved contractile strength. Importantly, in vitro expanded SCs engrafted the SC compartment and could regenerate muscle after secondary injury. These results demonstrate that Pax3 is able to promote the ex vivo expansion of SCs while maintaining their stem cell regenerative properties.

  9. Stand-up exercise training facilitates muscle recovery from disuse atrophy by stimulating myogenic satellite cell proliferation in mice.

    Science.gov (United States)

    Itoh, Yuta; Hayakawa, Kimihide; Mori, Tomohiro; Agata, Nobuhide; Inoue-Miyazu, Masumi; Murakami, Taro; Sokabe, Masahiro; Kawakami, Keisuke

    2014-11-01

    Determining the cellular and molecular recovery processes in inactivity - or unloading -induced atrophied muscles should improve rehabilitation strategies. We assessed the effects of stand-up exercise (SE) training on the recovery of atrophied skeletal muscles in male mice. Mice were trained to stand up and press an elevated lever in response to a light-tone cue preceding an electric foot shock and then subjected to tail suspension (TS) for 2 weeks to induce disuse atrophy in hind limb muscles. After release from TS, mice were divided into SE-trained (SE cues: 25 times per set, two sets per day) and non-SE-trained groups. Seven days after the training, average myofiber cross-sectional area (CSA) of the soleus muscle was significantly greater in the SE-trained group than in the non-SE-trained group (1843 ± 194 μm(2) vs. 1315 ± 153 μm(2)). Mean soleus muscle CSA in the SE trained group was not different from that in the CON group subjected to neither TS nor SE training (2005 ± 196 μm(2)), indicating that SE training caused nearly complete recovery from muscle atrophy. The number of myonuclei per myofiber was increased by ~60% in the SE-trained group compared with the non-SE-trained and CON groups (0.92 ± 0.03 vs. 0.57 ± 0.03 and 0.56 ± 0.11, respectively). The number of proliferating myonuclei, identified by 5-ethynyl-2'-deoxyuridine staining, increased within the first few days of SE training. Thus, it is highly likely that myogenic satellite cells proliferated rapidly in atrophied muscles in response to SE training and fused with existing myofibers to reestablish muscle mass.

  10. Comparison and analysis of Wuding and avian chicken skeletal muscle satellite cells

    NARCIS (Netherlands)

    Tong, H.Q.; Jiang, Z.Q.; Dou, T.F.; Li, Q.H.; Xu, Z.Q.; Liu, L.X.; Gu, D.H.; Rong, H.; Huang, Y.; Chen, X.B.; Jois, M.; Pas, te M.F.W.; Ge, C.R.; Jia, J.J.

    2016-01-01

    Chicken skeletal muscle satellite cells are located between the basement membrane and the sarcolemma of mature muscle fibers. Avian broilers have been genetically selected based on their high growth velocity and large muscle mass. The Wuding chicken is a famous local chicken in Yunnan Province th

  11. Whey protein supplementation accelerates satellite cell proliferation during recovery from eccentric exercise

    DEFF Research Database (Denmark)

    Farup, Jean; Rahbek, Stine Klejs; Knudsen, Inge Skovgaard

    2014-01-01

    Human skeletal muscle satellite cells (SCs) are essential for muscle regeneration and remodeling processes in healthy and clinical conditions involving muscle breakdown. However, the potential influence of protein supplementation on post-exercise SC regulation in human skeletal muscle has not bee...

  12. Reduced satellite cell numbers with spinal cord injury and aging in humans

    NARCIS (Netherlands)

    Verdijk, L.B.; Dirks, M.L.; Snijders, T.; Prompers, J.J.; Beelen, M.; Jonkers, R.A.; Thijssen, D.H.J.; Hopman, M.T.E.; Loon, L.J. van

    2012-01-01

    INTRODUCTION: Both sarcopenia and spinal cord injury (SCI) are characterized by the loss of skeletal muscle mass and function. Despite obvious similarities in atrophy between both models, differences in muscle fiber size and satellite cell content may exist on a muscle fiber type-specific level.

  13. Muscle atrophy reversed by growth factor activation of satellite cells in a mouse muscle atrophy model.

    Directory of Open Access Journals (Sweden)

    Simon Hauerslev

    Full Text Available Muscular dystrophies comprise a large group of inherited disorders that lead to progressive muscle wasting. We wanted to investigate if targeting satellite cells can enhance muscle regeneration and thus increase muscle mass. We treated mice with hepatocyte growth factor and leukemia inhibitory factor under three conditions: normoxia, hypoxia and during myostatin deficiency. We found that hepatocyte growth factor treatment led to activation of the Akt/mTOR/p70S6K protein synthesis pathway, up-regulation of the myognic transcription factors MyoD and myogenin, and subsequently the negative growth control factor, myostatin and atrophy markers MAFbx and MuRF1. Hypoxia-induced atrophy was partially restored by hepatocyte growth factor combined with leukemia inhibitory factor treatment. Dividing satellite cells were three-fold increased in the treatment group compared to control. Finally, we demonstrated that myostatin regulates satellite cell activation and myogenesis in vivo following treatment, consistent with previous findings in vitro. Our results suggest, not only a novel in vivo pharmacological treatment directed specifically at activating the satellite cells, but also a myostatin dependent mechanism that may contribute to the progressive muscle wasting seen in severely affected patients with muscular dystrophy and significant on-going regeneration. This treatment could potentially be applied to many conditions that feature muscle wasting to increase muscle bulk and strength.

  14. Alkaline regenerative fuel cell energy storage system for manned orbital satellites

    Science.gov (United States)

    Martin, R. E.; Gitlow, B.; Sheibley, D. W.

    1982-01-01

    It is pointed out that the alkaline regenerative fuel cell system represents a highly efficient, lightweight, reliable approach for providing energy storage in an orbiting satellite. In addition to its energy storage function, the system can supply hydrogen and oxygen for attitude control of the satellite and for life support. A summary is presented of the results to date obtained in connection with the NASA-sponsored fuel cell technology advancement program, giving particular attention to the requirements of the alkaline regenerative fuel cell and the low-earth mission. Attention is given to system design guidelines, weight considerations, gold-platinum cathode cell performance, matrix development, the electrolyte reservoir plate, and the cyclical load profile tests.

  15. Cycle training modulates satellite cell and transcriptional responses to a bout of resistance exercise.

    Science.gov (United States)

    Murach, Kevin A; Walton, R Grace; Fry, Christopher S; Michaelis, Sami L; Groshong, Jason S; Finlin, Brian S; Kern, Philip A; Peterson, Charlotte A

    2016-09-01

    This investigation evaluated whether moderate-intensity cycle ergometer training affects satellite cell and molecular responses to acute maximal concentric/eccentric resistance exercise in middle-aged women. Baseline and 72 h postresistance exercise vastus lateralis biopsies were obtained from seven healthy middle-aged women (56 ± 5 years, BMI 26 ± 1, VO2max 27 ± 4) before and after 12 weeks of cycle training. Myosin heavy chain (MyHC) I- and II-associated satellite cell density and cross-sectional area was determined via immunohistochemistry. Expression of 93 genes representative of the muscle-remodeling environment was also measured via NanoString. Overall fiber size increased ~20% with cycle training (P = 0.052). MyHC I satellite cell density increased 29% in response to acute resistance exercise before endurance training and 50% with endurance training (P training, MyHC I satellite cell density decreased by 13% in response to acute resistance exercise (acute resistance × training interaction, P trained state in response to resistance exercise. Similar satellite cell and gene expression response patterns indicate coordinated regulation of the muscle environment to promote adaptation. Moderate-intensity endurance cycle training modulates the response to acute resistance exercise, potentially conditioning the muscle for more intense concentric/eccentric activity. These results suggest that cycle training is an effective endurance exercise modality for promoting growth in middle-aged women, who are susceptible to muscle mass loss with progressing age.

  16. Brain and muscle Arnt-like 1 promotes skeletal muscle regeneration through satellite cell expansion

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Somik [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Yin, Hongshan [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Department of Cardiovascular Medicine, Third Affiliated Hospital, Hebei Medical University, Shijiazhuang 050051, Hebei (China); Nam, Deokhwa [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States); Li, Yong [Department of Pediatric Surgery, Center for Stem Cell Research and Regenerative Medicine, University of Texas Health Science Center at Houston, Houston, TX 77030 (United States); Ma, Ke, E-mail: kma@houstonmethodist.org [Center for Diabetes Research, Department of Medicine, Houston Methodist Research Institute, Houston, TX 77030 (United States)

    2015-02-01

    Circadian clock is an evolutionarily conserved timing mechanism governing diverse biological processes and the skeletal muscle possesses intrinsic functional clocks. Interestingly, although the essential clock transcription activator, Brain and muscle Arnt-like 1 (Bmal1), participates in maintenance of muscle mass, little is known regarding its role in muscle growth and repair. In this report, we investigate the in vivo function of Bmal1 in skeletal muscle regeneration using two muscle injury models. Bmal1 is highly up-regulated by cardiotoxin injury, and its genetic ablation significantly impairs regeneration with markedly suppressed new myofiber formation and attenuated myogenic induction. A similarly defective regenerative response is observed in Bmal1-null mice as compared to wild-type controls upon freeze injury. Lack of satellite cell expansion accounts for the regeneration defect, as Bmal1{sup −/−} mice display significantly lower satellite cell number with nearly abolished induction of the satellite cell marker, Pax7. Furthermore, satellite cell-derived primary myoblasts devoid of Bmal1 display reduced growth and proliferation ex vivo. Collectively, our results demonstrate, for the first time, that Bmal1 is an integral component of the pro-myogenic response that is required for muscle repair. This mechanism may underlie its role in preserving adult muscle mass and could be targeted therapeutically to prevent muscle-wasting diseases. - Highlights: • Bmal1 is highly inducible by muscle injury and myogenic stimuli. • Genetic ablation of Bmal1 significantly impairs muscle regeneration. • Bmal1 promotes satellite cell expansion during muscle regeneration. • Bmal1-deficient primary myoblasts display attenuated growth and proliferation.

  17. Fused-Polished Fiber Couplers

    Institute of Scientific and Technical Information of China (English)

    Sien; Chi; Shiao-Min; Tseng

    2003-01-01

    We report on fused-polished fiber couplers with a new fabrication method. This structure so fabricated is promising while achieving high-performance all-fiber WDM devices. Potential advantages and prospects of our works are presented.

  18. Regulation of turkey myogenic satellite cell migration by MicroRNAs miR-128 and miR-24.

    Science.gov (United States)

    Velleman, S G; Harding, R L

    2016-12-05

    Myogenic satellite cells are an adult stem cell responsible for all post-hatch muscle growth in poultry. As a stem cell population, satellite cells are highly heterogeneous, but the origin of this heterogeneity remains unclear. Heterogeneity is, in part, regulated by gene expression. One method of endogenous gene regulation that may contribute to heterogeneity is microRNAs (miRNAs). Two miRNAs previously shown to regulate poultry myogenic satellite cell proliferation and differentiation, miR-128 and miR-24, were studied to determine if they also affected satellite cell migration. Satellite cell migration is an essential step for both proliferation and differentiation. During proliferation, satellite cells will migrate and align to form new myofibers or donate their nuclei to existing myofibers leading to muscle fiber hypertrophy or regeneration. Transient transfection of miRNA specific mimics to each miRNA reduced migration of satellite cells following a cell culture scratch at 72 h of proliferation when the cultures were 90 to 100% confluent. However, only the migration in cells transfected with miR-24 mimics at 24 and 30 h following the scratch was significantly reduced (P ≤ 0.05) to around 70% of the distance migrated by controls. Alternately, transfection with inhibitors specific to miR-128 or miR-24 significantly (P ≤ 0.05) increased migration between 147 and 252% compared to their controls between 24 and 48 h following the scratch. These data demonstrate that miR-128 and miR-24 play a role in myogenic satellite cell migration, which will impact muscle development and growth.

  19. Thermal fatigue of electrical fuses

    Directory of Open Access Journals (Sweden)

    Gelet Jean-Louis

    2014-06-01

    Full Text Available Electric Fuses have to respect different national or international standards such as IEC (International Electro-technical Commission 269. These standards define the characteristics of the fuses and describe the tests to be run in order to check fuse's ability to take up their main functions, i.e. current-conduction and operation under overloads and short-circuits. But fuses never carry current neither operate under standardized conditions. For example, rated current is evaluated under specified ambient temperature, without cooling air-flow, and with 1 meter-long connection-cables on both sides. In the field, temperature can reach up 80∘C, with or without air-flow and connection-parts are much more shorter. An issue is that current is never constant, often being cyclingly applied; equipments are frequently in use during the day and stopped in the night. ON-time and OFF-time generate alternative heating, then alternative stresses leading to thermal fatigue. MERSEN run many tests along the years, allowing to develop a method for choosing right fuses for each application. As a result, fuses don't melt unexpectedly in the field, but the method is supposed to be conservative and does not permit to get a better understanding of the phenomena neither an improvement of the products. The paper presents some specific ageing-tests run on conductive elements and tries to establish a correspondence between these tests and others carried out on complete fuses. Tests have been run on silver and copper, but their principle could be interesting for any structural material, especially because it underlines crack-opening.

  20. Critical amino acids in syndecan-4 cytoplasmic domain modulation of turkey satellite cell growth and development.

    Science.gov (United States)

    Song, Yan; McFarland, Douglas C; Velleman, Sandra G

    2012-02-01

    Syndecan-4 is composed of a core protein and covalently attached glycosaminoglycan (GAG) and N-linked glycosylated (N-glycosylated) chains. The core protein is divided into extracellular, transmembrane, and cytoplasmic domains. The cytoplasmic domain has two conserved regions and a variable region in the middle. The Ser residue in the conserved region 1 and the Tyr residue in the variable region are important in regulating protein kinase C alpha (PKCα) membrane localization and focal adhesion formation. The objective of the current study was to investigate the role of syndecan-4 Ser and Tyr residues in combination with the GAG and N-glycosylated chains in turkey satellite cell proliferation, differentiation, fibroblast growth factor 2 (FGF2) responsiveness, and PKCα membrane localization. Site-directed mutagenesis was used to generate Ser and Tyr mutants with or without GAG and N-glycosylated chains. The wild type and mutant syndecan-4 constructs were transfected into turkey satellite cells. The over-expression of Ser and Tyr mutants increased cell proliferation and differentiation and decreased membrane localization of PKCα. Furthermore, Ser mutants enhanced cellular responsiveness to FGF2. The results from this study are the first demonstration of a role of syndecan-4 cytoplasmic domain Ser and Tyr residues in regulating satellite cell proliferation, differentiation, and the modulation of cellular responsiveness to FGF2.

  1. Synthesis of new cis-fused tetrahydrochromeno[4,3-b]quinolines and their antiproliferative activity studies against MDA-MB-231 and MCF-7 breast cancer cell lines.

    Science.gov (United States)

    Nagaiah, K; Venkatesham, A; Srinivasa Rao, R; Saddanapu, V; Yadav, J S; Basha, S J; Sarma, A V S; Sridhar, B; Addlagatta, A

    2010-06-01

    New cis-fused tetrahydrochromeno[4,3-b]quinolines have been synthesized by intramolecular [4+2] imino-Diels-Alder reactions of 2-azadienes derived in situ from aromatic amines and 7-O-prenyl derivatives of 8-formyl-2,3-disubstituted chromenones in the presence of 20mol% Yb(OTf)(3) in acetonitrile under reflux conditions in good to excellent yields. The structures were established by spectroscopic data and further confirmed by X-ray diffraction analysis. These compounds were evaluated for their antiproliferative activity against MDA-MB-231 and MCF-7 breast cancer cells. The results showed that compounds 3e, 3f, and 3k exhibit significant antiproliferative activity against MCF-7 breast cancer cells and low inhibitory activity against MDA-MB-231 breast cancer cell lines. Compound 3h displayed activity as comparable to tamoxifen on both the cell lines.

  2. Plasticity and recovery of skeletal muscle satellite cells during limb regeneration.

    Science.gov (United States)

    Morrison, Jamie I; Borg, Paula; Simon, András

    2010-03-01

    Salamander limb regeneration depends on local progenitors whose progeny are recruited to the new limb. We previously identified a Pax7(+) cell population in skeletal muscle whose progeny have the potential to contribute to the regenerating limb. However, the plasticity of individual Pax7(+) cells, as well as their recovery within the new limb, was unclear. Here, we show that Pax7(+) cells remain present after multiple rounds of limb amputation/regeneration. Pax7(+) cells are found exclusively within skeletal muscle in the regenerating limb and proliferate where the myofibers are growing. Pax7 is rapidly down-regulated in the blastema, and analyses of clonal derivatives show that Pax7(+) cell progeny are not restricted to skeletal muscle during limb regeneration. Our data suggest that the newt regeneration blastema is not entirely a composite of lineage-restricted progenitors. The results demonstrate that except for a transient and subsequently blunted increase, skeletal muscle satellite cells constitute a stable pool of reserve cells for multiple limb regeneration events.-Morrison, J. I., Borg, P., Simon, A. Plasticity and recovery of skeletal muscle satellite cells during limb regeneration.

  3. Satellite cell response to erythropoietin treatment and endurance training in healthy young men

    DEFF Research Database (Denmark)

    Hoedt, Andrea; Christensen, Britt; Nellemann, Birgitte

    2016-01-01

    KEY POINT: Erythropoietin (Epo) treatment may induce myogenic differentiation factor (MyoD) expression and prevent apoptosis in satellite cells (SCs) in murine and in vitro models. Endurance training stimulates SC proliferation in vivo in murine and human skeletal muscle. In the present study, we...... show, in human skeletal muscle, that treatment with an Epo-stimulating agent (darbepoetin-α) in vivo increases the content of MyoD(+) SCs in healthy young men. Moreover, we report that Epo receptor mRNA is expressed in adult human SCs, suggesting that Epo may directly target SCs through ligand......-term Epo treatment during disease conditions involving anaemia may impact SCs and warrants further investigation. Satellite cell (SC) proliferation is observed following erythropoitin treatment in vitro in murine myoblasts and endurance training in vivo in human skeletal muscle. The present study aimed...

  4. Hepatocyte Growth Factor-mediated satellite cells niche perturbation promotes development of distinct sarcoma subtypes.

    Science.gov (United States)

    Morena, Deborah; Maestro, Nicola; Bersani, Francesca; Forni, Paolo Emanuele; Lingua, Marcello Francesco; Foglizzo, Valentina; Šćepanović, Petar; Miretti, Silvia; Morotti, Alessandro; Shern, Jack F; Khan, Javed; Ala, Ugo; Provero, Paolo; Sala, Valentina; Crepaldi, Tiziana; Gasparini, Patrizia; Casanova, Michela; Ferrari, Andrea; Sozzi, Gabriella; Chiarle, Roberto; Ponzetto, Carola; Taulli, Riccardo

    2016-03-17

    Embryonal Rhabdomyosarcoma (ERMS) and Undifferentiated Pleomorphic Sarcoma (UPS) are distinct sarcoma subtypes. Here we investigate the relevance of the satellite cell (SC) niche in sarcoma development by using Hepatocyte Growth Factor (HGF) to perturb the niche microenvironment. In a Pax7 wild type background, HGF stimulation mainly causes ERMS that originate from satellite cells following a process of multistep progression. Conversely, in a Pax7 null genotype ERMS incidence drops, while UPS becomes the most frequent subtype. Murine EfRMS display genetic heterogeneity similar to their human counterpart. Altogether, our data demonstrate that selective perturbation of the SC niche results in distinct sarcoma subtypes in a Pax7 lineage-dependent manner, and define a critical role for the Met axis in sarcoma initiation. Finally, our results provide a rationale for the use of combination therapy, tailored on specific amplifications and activated signaling pathways, to minimize resistance emerging from sarcomas heterogeneity.

  5. Muscle Atrophy Reversed by Growth Factor Activation of Satellite Cells in a Mouse Muscle Atrophy Model

    DEFF Research Database (Denmark)

    Hauerslev, Simon; Vissing, John; Krag, Thomas O

    2014-01-01

    Muscular dystrophies comprise a large group of inherited disorders that lead to progressive muscle wasting. We wanted to investigate if targeting satellite cells can enhance muscle regeneration and thus increase muscle mass. We treated mice with hepatocyte growth factor and leukemia inhibitory...... factor under three conditions: normoxia, hypoxia and during myostatin deficiency. We found that hepatocyte growth factor treatment led to activation of the Akt/mTOR/p70S6K protein synthesis pathway, up-regulation of the myognic transcription factors MyoD and myogenin, and subsequently the negative growth...... control factor, myostatin and atrophy markers MAFbx and MuRF1. Hypoxia-induced atrophy was partially restored by hepatocyte growth factor combined with leukemia inhibitory factor treatment. Dividing satellite cells were three-fold increased in the treatment group compared to control. Finally, we...

  6. The effect of nutritional status and myogenic satellite cell age on turkey satellite cell proliferation, differentiation, and expression of myogenic transcriptional regulatory factors and heparan sulfate proteoglycans syndecan-4 and glypican-1.

    Science.gov (United States)

    Harthan, Laura B; McFarland, Douglas C; Velleman, Sandra G

    2014-01-01

    Posthatch satellite cell mitotic activity is a critical component of muscle development and growth. Satellite cells are myogenic stem cells that can be induced by nutrition to follow other cellular developmental pathways, and whose mitotic activity declines with age. The objective of the current study was to determine the effect of restricting protein synthesis on the proliferation and differentiation, expression of myogenic transcriptional regulatory factors myogenic determination factor 1, myogenin, and myogenic regulatory factor 4, and expression of the heparan sulfate proteoglycans syndecan-4 and glypican-1 in satellite cells isolated from 1-d-, 7-wk-, and 16-wk-old turkey pectoralis major muscle (1 d, 7 wk, and 16 wk cells, respectively) by using variable concentrations of Met and Cys. Four Met concentrations-30 (control), 7.5, 3, or 0 mg/L with 3.2 mg/L of Cys per 1 mg/L of Met-were used for culture of satellite cells to determine the effect of nutrition and age on satellite cell behavior during proliferation and differentiation. Proliferation was reduced by lower Met and Cys concentrations in all ages at 96 h of proliferation. Differentiation was increased in the 1 d Met-restricted cells, whereas the 7 wk cells treated with 3 mg/L of Met had decreased differentiation. Reduced Met and Cys levels from the control did not significantly affect the 16 wk cells at 72 h of differentiation. However, medium with no Met or Cys suppressed differentiation at all ages. The expression of myogenic determination factor 1, myogenin, myogenic regulatory factor 4, syndecan-4, and glypican-1 was differentially affected by age and Met or Cys treatment. These data demonstrate the age-specific manner in which turkey pectoralis major muscle satellite cells respond to nutritional availability and the importance of defining optimal nutrition to maximize satellite cell proliferation and differentiation for subsequent muscle mass accretion.

  7. Effects of Massage on Satellite Cells of Acute Contusive Skeletal Muscles

    Institute of Scientific and Technical Information of China (English)

    胡军; 张喜林; 严隽陶

    2007-01-01

    Objective: To study the mechanism of Tuina in the treatment of skeletal muscle injury. Methods: Rabbits were heavily beaten at gastrocnemius muscle to make acute contusion model and then treated respectively by early Tuina and routine Tuina. The number of satellite cells of skeletal muscles was observed. Results: The number of the satellite cells continued to grow in both groups, and it began to increase significantly 3-5 days after Tuina treatment. Early Tuina treatment produces larger number of satellite cells than routine Tuina treatment.Conclusion: Early Tuina treatment is helpful to the marked recovery of skeletal muscles by increasing the number of satellite cell.%目的:探讨推拿治疗骨骼肌损伤的机理.方法:以重物打击方式造成腓肠肌急性挫伤模型,施以早期推拿治疗和常规推拿治疗,观察骨骼肌卫星细胞数量变化.结果:各组卫星细胞数量均呈持续上升趋势,常规治疗组和早期手法组的卫星细胞数量在3~5 d时就开始有大幅度上升.早期手法组卫星细胞数量多于常规治疗组.结论:早期手法对卫星细胞数增加作用明显有助于骨骼肌功能恢复.

  8. Molecular basis of the myogenic profile of aged human skeletal muscle satellite cells during differentiation

    OpenAIRE

    Pietrangelo, Tiziana; Puglielli, Cristina; Mancinelli, Rosa; Beccafico, Sara; Fanò, Giorgio; Fulle, Stefania

    2009-01-01

    Abstract Sarcopenia is the age-related loss of muscle mass, strength and function. Human muscle proteins are synthesized at a slower rate in the elderly than in young adults, leading to atrophy and muscle mass loss with a decline in the functional capability. Additionally, aging is accompanied by a decrease in the ability of muscle tissue to regenerate following injury or overuse due to the impairment of intervening satellite cells, in which we previously reported oxidative damage ...

  9. Effects of voluntary wheel running on satellite cells in the rat plantaris muscle

    OpenAIRE

    Atsushi Kojima; Mitsutoshi Kurosaka; Yuji Ogura; Hisashi Naito; Shizuo Katamoto; Katsumasa Goto

    2009-01-01

    This study investigated the effects of voluntary wheel running on satellite cells in the rat plantaris muscle. Seventeen 5-week-old male Wistar rats were assigned to a control (n = 5) or training (n = 12) group. Each rat in the training group ran voluntarily in a running-wheel cage for 8 weeks. After the training period, the animals were anesthetized, and the plantaris muscles were removed, weighed, and analyzed immunohistochemically and biochemically. Although there were no significant diffe...

  10. Fibromodulin: a master regulator of myostatin controlling progression of satellite cells through a myogenic program.

    Science.gov (United States)

    Lee, Eun Ju; Jan, Arif Tasleem; Baig, Mohammad Hassan; Ashraf, Jalaluddin Mohammad; Nahm, Sang-Soep; Kim, Yong-Woon; Park, So-Young; Choi, Inho

    2016-08-01

    Differentiation of muscle satellite cells (MSCs) involves interaction of the proteins present in the extracellular matrix (ECM) with MSCs to regulate their activity, and therefore phenotype. Herein, we report fibromodulin (FMOD), a member of the proteoglycan family participating in the assembly of ECM, as a novel regulator of myostatin (MSTN) during myoblast differentiation. In addition to having a pronounced effect on the expression of myogenic marker genes [myogenin (MYOG) and myosin light chain 2 (MYL2)], FMOD was found to maintain the transcriptional activity of MSTN Moreover, coimmunoprecipitation and in silico studies performed to investigate the interaction of FMOD helped confirm that it antagonizes MSTN function by distorting its folding and preventing its binding to activin receptor type IIB. Furthermore, in vivo studies revealed that FMOD plays an active role in healing by increasing satellite cell recruitment to sites of injury. Together, these findings disclose a hitherto unrecognized regulatory role for FMOD in MSCs and highlight new mechanisms whereby FMOD circumvents the inhibitory effects of MSTN and triggers myoblast differentiation. These findings offer a basis for the design of novel MSTN inhibitors that promote muscle regeneration after injury or for the development of pharmaceutical agents for the treatment of different muscle atrophies.-Lee, E. J., Jan, A. T., Baig, M. H., Ashraf, J. M., Nahm, S.-S., Kim, Y.-W., Park, S.-Y., Choi, I. Fibromodulin: a master regulator of myostatin controlling progression of satellite cells through a myogenic program.

  11. Satellite SAR observation of the sea surface wind field caused by rain cells

    Institute of Scientific and Technical Information of China (English)

    YE Xiaomin; LIN Mingsen; YUAN Xinzhe; DING Jing; XIE Xuetong; ZHANG Yi; XU Ying

    2016-01-01

    Rain cells or convective rain, the dominant form of rain in the tropics and subtropics, can be easy detected by satellite Synthetic Aperture Radar (SAR) images with high horizontal resolution. The footprints of rain cells on SAR images are caused by the scattering and attenuation of the rain drops, as well as the downward airflow. In this study, we extract sea surface wind field and its structure caused by rain cells by using a RADARSAT-2 SAR image with a spatial resolution of 100 m for case study. We extract the sea surface wind speeds from SAR image by using CMOD4 geophysical model function with outside wind directions of NCEP final operational global analysis data, Advance Scatterometer (ASCAT) onboard European MetOp-A satellite and microwave scatterometer onboard Chinese HY-2 satellite, respectively. The root-mean-square errors (RMSE) of these SAR wind speeds, validated against NCEP, ASCAT and HY-2, are 1.48 m/s, 1.64 m/s and 2.14 m/s, respectively. Circular signature patterns with brighter on one side and darker on the opposite side on SAR image are interpreted as the sea surface wind speed (or sea surface roughness) variety caused by downdraft associated with rain cells. The wind speeds taken from the transect profile which superposes to the wind ambient vectors and goes through the center of the circular footprint of rain cell can be fitted as a cosine or sine curve in high linear correlation with the values of no less than 0.80. The background wind speed, the wind speed caused by rain cell and the diameter of footprint of the rain cell with kilometers or tens of kilometers can be acquired by fitting curve. Eight cases interpreted and analyzed in this study all show the same conclusion.

  12. Rainbow trout (Oncorhynchus mykiss) muscle satellite cells are targets of salmonid alphavirus infection.

    Science.gov (United States)

    Biacchesi, Stéphane; Jouvion, Grégory; Mérour, Emilie; Boukadiri, Abdelhak; Desdouits, Marion; Ozden, Simona; Huerre, Michel; Ceccaldi, Pierre-Emmanuel; Brémont, Michel

    2016-01-08

    Sleeping disease in rainbow trout is characterized by an abnormal swimming behaviour of the fish which stay on their side at the bottom of the tanks. This sign is due to extensive necrosis and atrophy of red skeletal muscle induced by the sleeping disease virus (SDV), also called salmonid alphavirus 2. Infections of humans with arthritogenic alphaviruses, such as Chikungunya virus (CHIKV), are global causes of debilitating musculoskeletal diseases. The mechanisms by which the virus causes these pathologies are poorly understood due to the restrictive availability of animal models capable of reproducing the full spectrum of the disease. Nevertheless, it has been shown that CHIKV exhibits a particular tropism for muscle stem cells also known as satellite cells. Thus, SDV and its host constitute a relevant model to study in details the virus-induced muscle atrophy, the pathophysiological consequences of the infection of a particular cell-type in the skeletal muscle, and the regeneration of the muscle tissue in survivors together with the possible virus persistence. To study a putative SDV tropism for that particular cell type, we established an in vivo and ex vivo rainbow trout model of SDV-induced atrophy of the skeletal muscle. This experimental model allows reproducing the full panel of clinical signs observed during a natural infection since the transmission of the virus is arthropod-borne independent. The virus tropism in the muscle tissue was studied by immunohistochemistry together with the kinetics of the muscle atrophy, and the muscle regeneration post-infection was observed. In parallel, an ex vivo model of SDV infection of rainbow trout satellite cells was developed and virus replication and persistence in that particular cell type was followed up to 73 days post-infection. These results constitute the first observation of a specific SDV tropism for the muscle satellite cells.

  13. Marine Lectins DlFBL and HddSBL Fused with Soluble Coxsackie-Adenovirus Receptor Facilitate Adenovirus Infection in Cancer Cells BUT Have Different Effects on Cell Survival

    Science.gov (United States)

    Wu, Bingbing; Mei, Shengsheng; Cui, Lianzhen; Zhao, Zhenzhen; Chen, Jianhong; Wu, Tao; Li, Gongchu

    2017-01-01

    Cancer development and progression are usually associated with glycosylation change, providing prognostic and diagnostic biomarkers, as well as therapeutic targets, for various cancers. In this work, Dicentrarchus labrax fucose binding lectin (DlFBL) and Haliotis discus discus sialic acid binding lectin (HddSBL) were genetically fused with soluble coxsackie-adenovirus receptor (sCAR), and produced through a bacterial expression system. Results showed that recombinant sCAR-DlFBL not only facilitated adenovirus Ad-EGFP infection in K562/ADR and U87MG cells, but also enhanced the cytotoxicity of adenovirus harboring gene encoding Pinellia pedatisecta agglutinin (PPA) or DlFBL (Ad-PPA or Ad-DlFBL) on U87MG cells through inducing apoptosis. Recombinant sCAR-HddSBL facilitated Ad-EGFP infection, but dramatically counteracted the cytotoxicity of both Ad-PPA and Ad-DlFBL in U87MG cells. Further analysis revealed that sCAR-HddSBL, but not sCAR-DlFBL, significantly upregulated transcription factor E2F1 levels in U87MG cells, which might be responsible for the adverse effect of sCAR-HddSBL on Ad-PPA and Ad-DlFBL. Taken together, our data suggested that sCAR-DlFBL could be further developed to redirect therapeutic adenoviruses to infect cancer cells such as U87MG, and the sCAR-lectin fusion proteins for adenoviral retargeting should be carefully examined for possible survival signaling induced by lectins, such as HddSBL. PMID:28335432

  14. Optical Performance Modeling of FUSE Telescope Mirror

    Science.gov (United States)

    Saha, Timo T.; Ohl, Raymond G.; Friedman, Scott D.; Moos, H. Warren

    2000-01-01

    We describe the Metrology Data Processor (METDAT), the Optical Surface Analysis Code (OSAC), and their application to the image evaluation of the Far Ultraviolet Spectroscopic Explorer (FUSE) mirrors. The FUSE instrument - designed and developed by the Johns Hopkins University and launched in June 1999 is an astrophysics satellite which provides high resolution spectra (lambda/Delta(lambda) = 20,000 - 25,000) in the wavelength region from 90.5 to 118.7 nm The FUSE instrument is comprised of four co-aligned, normal incidence, off-axis parabolic mirrors, four Rowland circle spectrograph channels with holographic gratings, and delay line microchannel plate detectors. The OSAC code provides a comprehensive analysis of optical system performance, including the effects of optical surface misalignments, low spatial frequency deformations described by discrete polynomial terms, mid- and high-spatial frequency deformations (surface roughness), and diffraction due to the finite size of the aperture. Both normal incidence (traditionally infrared, visible, and near ultraviolet mirror systems) and grazing incidence (x-ray mirror systems) systems can be analyzed. The code also properly accounts for reflectance losses on the mirror surfaces. Low frequency surface errors are described in OSAC by using Zernike polynomials for normal incidence mirrors and Legendre-Fourier polynomials for grazing incidence mirrors. The scatter analysis of the mirror is based on scalar scatter theory. The program accepts simple autocovariance (ACV) function models or power spectral density (PSD) models derived from mirror surface metrology data as input to the scatter calculation. The end product of the program is a user-defined pixel array containing the system Point Spread Function (PSF). The METDAT routine is used in conjunction with the OSAC program. This code reads in laboratory metrology data in a normalized format. The code then fits the data using Zernike polynomials for normal incidence

  15. On spatial distribution of proton radiation belt from solar cell degradation of Akebono satellite

    Science.gov (United States)

    Miyake, W.; Miyoshi, Y.; Matsuoka, A.

    2013-12-01

    Solar cells on any satellite degrade gradually due to severe space radiation environment. We found a fair correlation between the decrease rate of solar cell output current of Akebono satellite orbiting in the inner magnetosphere and trapped proton flux from AP8 model between 1989 and 1992. After 1993, presumably as a result of long-term degradation, variation of solar cell output seems more susceptible to other causes such as high temperature effect, and simple monthly averaged data show no significant relation between them. One of possible causes for the temperature variation of the solar cells is terrestrial heat radiation with changing orientation of solar cell panels towards the earth and another is solar radiation varied with eccentric earth's orbit around the sun. In order to remove the possible temperature effect, we sort the data expected to be least affected by the terrestrial heat radiation from the orbit conditions, and also analyze difference of the output current for a month from that for the same month in the previous year. The analysis method leads us to successfully track a continuous correlation between the decease rate of solar cell output and energetic trapped proton flux up to 1996. We also discuss the best-fitted spatial distribution of energetic protons from comparison with model calculations.

  16. Liquefier Dynamics in Fused Deposition

    DEFF Research Database (Denmark)

    Bellini, Anna; Guceri, Selcuk; Bertoldi, Maurizio

    2004-01-01

    Layered manufacturing (LM) is an evolution of rapid prototyping (RP) technology whereby a part is built in layers. Fused deposition modeling (FDM) is a particular LM technique in which each section is fabricated through vector style deposition of building blocks, called roads, which...

  17. Commitment of Satellite Cells Expressing the Calcium Channel α2δ1 Subunit to the Muscle Lineage

    Directory of Open Access Journals (Sweden)

    Tammy Tamayo

    2012-01-01

    Full Text Available Satellite cells can maintain or repair muscle because they possess stem cell properties, making them a valuable option for cell therapy. However, cell transplants into skeletal muscle of patients with muscular dystrophy are limited by donor cell attachment, migration, and survival in the host tissue. Cells used for therapy are selected based on specific markers present in the plasma membrane. Although many markers have been identified, there is a need to find a marker that is expressed at different states in satellite cells, activated, quiescent, or differentiated cell. Furthermore, the marker has to be present in human tissue. Recently we reported that the plasma membrane α2δ1 protein is involved in cell attachment and migration in myoblasts. The α2δ1 subunit forms a part of the L-type voltage-dependent calcium channel in adult skeletal muscle. We found that the α2δ1 subunit is expressed in the majority of newly isolated satellite cells and that it appears earlier than the α1 subunits and at higher levels than the β or γ subunits. We also found that those cells that expressed α2δ1 would differentiate into muscle cells. This evidence indicates that the α2δ1 may be used as a marker of satellite cells that will differentiate into muscle.

  18. Reduced satellite cell number in situ in muscular contractures from children with cerebral palsy.

    Science.gov (United States)

    Dayanidhi, Sudarshan; Dykstra, Peter B; Lyubasyuk, Vera; McKay, Bryon R; Chambers, Henry G; Lieber, Richard L

    2015-07-01

    Satellite cells (SC) are quiescent adult muscle stem cells critical for postnatal development. Children with cerebral palsy have impaired muscular growth and develop contractures. While flow cytometry previously demonstrated a reduced SC population, extracellular matrix abnormalities may influence the cell isolation methods used, systematically isolating fewer cells from CP muscle and creating a biased result. Consequently, the purpose of this study was to use immunohistochemistry on serial muscle sections to quantify SC in situ. Serial cross-sections from human gracilis muscle biopsies (n = 11) were labeled with fluorescent antibodies for Pax7 (SC transcriptional marker), laminin (basal lamina), and 4',6-diamidino-2-phenylindole (nuclei). Fluorescence microscopy under high magnification was used to identify SC based on labeling and location. Mean SC/100 myofibers was reduced by ∼70% (p muscle growth and apparent decreased responsiveness of CP muscle to exercise. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  19. The vascular endothelial growth factor expression and vascular regeneration in infarcted myocardium by skeletal muscle satellite cells

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Background Myocardial infarction results in tissue necrosis, leading to cell loss and ultimately to cardiac failure. Implantation of skeletal muscle satellite cells into the scar area may compensate for the cell loss and provides a new strategy for infarct therapy. Vascular endothelial growth factor (VEGF) is a promising reagent for inducing myocardial angiogenesis. Skeletal myoblast transplantation has been shown to improve cardiac function in chronic heart failure models by regenerating muscle. We hypothesized that VEGF expression and vascular regeneration increased in infarcted myocardium by skeletal muscle satellite cells, which can promote vascular producing and improve survival environment in infarcted myocardium.Methods The skeletal muscle satellite cells were implanted into the infarcted myocardium in a model through ligated left anterior artery in Louis Inbrad Strain rat. Specimens were got for identifying the expression of VEGF and the density of vascular by immunochemical method at two weeks after implantation. Results The proliferation and differentiation of the skeletal muscle satellite cell was very well. The expression of VEGF was higher in the implanted group (146.83±2.49) than that in the control group (134.26±6.84) (P<0.05). The vascular density in the implanted group (13.00±1.51) was also higher than that in the control (10.68±1.79) (P<0.05). Conclusion The implanted satellite cell could excrete growth factor that would induce angiogenesis and improve cell survival environment in infarcted myocardium.

  20. The long, the short, and the micro: a polyA tale of Pax3 in satellite cells.

    Science.gov (United States)

    Pasut, Alessandra; Rudnicki, Michael A

    2012-03-02

    The use of alternative polyadenylation sites is emerging as an important regulator of gene expression. In this issue of Cell Stem Cell, Boutet et al. (2012) report that alternative 3'UTRs of the Pax3 transcript restrict its expression to axial satellite cells through miR-mediated targeting of one of the isoforms. Copyright © 2012 Elsevier Inc. All rights reserved.

  1. Satellite Cells CD44 Positive Drive Muscle Regeneration in Osteoarthritis Patients

    Directory of Open Access Journals (Sweden)

    Manuel Scimeca

    2015-01-01

    Full Text Available Age-related bone diseases, such as osteoarthritis and osteoporosis, are strongly associated with sarcopenia and muscle fiber atrophy. In this study, we analyzed muscle biopsies in order to demonstrate that, in osteoarthritis patients, both osteophytes formation and regenerative properties of muscle stem cells are related to the same factors. In particular, thanks to immunohistochemistry, transmission electron microscopy, and immunogold labeling we investigated the role of BMP-2 in muscle stem cells activity. In patients with osteoarthritis both immunohistochemistry and transmission electron microscopy allowed us to note a higher number of CD44 positive satellite muscle cells forming syncytium. Moreover, the perinuclear and cytoplasmic expression of BMP-2 assessed by in situ molecular characterization of satellite cells syncytia suggest a very strict correlation between BMP-2 expression and muscle regeneration capability. Summing up, the higher BMP-2 expression in osteoarthritic patients could explain the increased bone mineral density as well as decreased muscle atrophy in osteoarthrosic patients. In conclusion, our results suggest that the control of physiological BMP-2 balance between bone and muscle tissues may be considered as a potential pharmacological target in bone-muscle related pathology.

  2. Satellite cell activation induced by aerobic muscle adaptation in response to endurance exercise in humans and rodents.

    Science.gov (United States)

    Abreu, Phablo; Mendes, Sávio Victor Diógenes; Ceccatto, Vânia Marilande; Hirabara, Sandro Massao

    2017-02-01

    Although the requirement of satellite cells activation and expansion following injury, mechanical load or growth stimulus provoked by resistance exercise has been well established, their function in response to aerobic exercise adaptation remains unclear. A clear relationship between satellite cell expansion in fiber-type specific myosin heavy chain and aerobic performance has been related, independent of myonuclear accretion or muscle growth. However, the trigger for this activation process is not fully understood yet and it seems to be a multi-faceted and well-orchestrated process. Emerging in vitro studies suggest a role for metabolic pathways and oxygen availability for satellite cell activation, modulating the self-renewal potential and cell fate control. The goal of this review is to describe and discuss the current knowledge about the satellite cell activation and expansion in response to aerobic exercise adaptation in human and rodent models. Additionally, findings about the in vitro metabolic control, which seems be involved in the satellite cell activation and cell fate control, are presented and discussed.

  3. Candidate solar cell materials for photovoltaic conversion in a solar power satellite /SPS/

    Science.gov (United States)

    Glaser, P. E.; Almgren, D. W.

    1978-01-01

    In recognition of the obstacles to solar-generated baseload power on earth, proposals have been made to locate solar power satellites in geosynchronous earth orbit (GEO), where solar energy would be available 24 hours a day during most of the time of the year. In an SPS, the electricity produced by solar energy conversion will be fed to microwave generators forming part of a planar phase-array transmitting antenna. The antenna is designed to precisely direct a microwave beam of very low intensity to one or more receiving antennas at desired locations on earth. At the receiving antenna, the microwave energy will be safely and efficiently reconverted to electricity and then be transmitted to consumers. An SPS system will include a number of satellites in GEO. Attention is given to the photovoltaic option for solar energy conversion in GEO, solar cell requirements, the availability of materials, the implication of large production volumes, requirements for high-volume manufacture of solar cell arrays, and the effects of concentration ratio on solar cell array area.

  4. Transcription of Satellite III non-coding RNAs is a general stress response in human cells

    Science.gov (United States)

    Valgardsdottir, Rut; Chiodi, Ilaria; Giordano, Manuela; Rossi, Antonio; Bazzini, Silvia; Ghigna, Claudia; Riva, Silvano; Biamonti, Giuseppe

    2008-01-01

    In heat-shocked human cells, heat shock factor 1 activates transcription of tandem arrays of repetitive Satellite III (SatIII) DNA in pericentromeric heterochromatin. Satellite III RNAs remain associated with sites of transcription in nuclear stress bodies (nSBs). Here we use real-time RT-PCR to study the expression of these genomic regions. Transcription is highly asymmetrical and most of the transcripts contain the G-rich strand of the repeat. A low level of G-rich RNAs is detectable in unstressed cells and a 104-fold induction occurs after heat shock. G-rich RNAs are induced by a wide range of stress treatments including heavy metals, UV-C, oxidative and hyper-osmotic stress. Differences exist among stressing agents both for the kinetics and the extent of induction (>100- to 80.000-fold). In all cases, G-rich transcripts are associated with nSBs. On the contrary, C-rich transcripts are almost undetectable in unstressed cells and modestly increase after stress. Production of SatIII RNAs after hyper-osmotic stress depends on the Tonicity Element Binding Protein indicating that activation of the arrays is triggered by different transcription factors. This is the first example of a non-coding RNA whose transcription is controlled by different transcription factors under different growth conditions. PMID:18039709

  5. Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

    Science.gov (United States)

    Glaser, P. E.

    1974-01-01

    The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

  6. Analyses of the differentiation potential of satellite cells from myoD-/-, mdx, and PMP22 C22 mice

    Directory of Open Access Journals (Sweden)

    Huxley Clare

    2005-03-01

    Full Text Available Abstract Background Sporadic and sometimes contradictory studies have indicated changes in satellite cell behaviour associated with the progressive nature of human Duchenne muscular dystrophy (DMD. Satellite cell proliferation and number are reportedly altered in DMD and the mdx mouse model. We recently found that satellite cells in MSVski transgenic mice, a muscle hypertrophy model showing progressive muscle degeneration, display a severe ageing-related differentiation defect in vitro. We tested the hypothesis that similar changes contribute to the gradual loss of muscle function with age in mdx and PMP22 mice, a model of human motor and sensory neuropathy type 1A (HMSN1A. Methods Single extensor digitorum longus muscle fibres were cultured from mdx and PMP22 mice and age- and genetic background-matched controls. Mice at several ages were compared with regard to the differentiation of satellite cells, assayed as the proportion of desmin-expressing cells that accumulated sarcomeric myosin heavy chain. Results Satellite cells of 2 month, 6 month, and 12 month old mdx mice were capable of differentiating to a similar extent to age-matched wild type control animals in an in vitro proliferation/differentiation model. Strikingly, differentiation efficiency in individual 6 month and 12 month old mdx animals varies to a much higher extent than in age-matched controls, younger mdx animals, or PMP22 mice. In contrast, differentiation of myoblasts from all myoD null mice assayed was severely impaired in this assay system. The defect in satellite cell differentiation that occurs in some mdx animals arises from a delay in differentiation that is not overcome by IGF-1 treatment at any phase of cultivation. Conclusion Overall, a defect in satellite cell differentiation above that arising through normal ageing does not occur in mdx or PMP22 mouse models of human disease. Nonetheless, the impaired differentiation of satellite cells from some mdx animals

  7. Satellite cells senescence in limb muscle of severe patients with COPD.

    Directory of Open Access Journals (Sweden)

    Marie-Eve Thériault

    Full Text Available RATIONALE: The maintenance of peripheral muscle mass may be compromised in chronic obstructive pulmonary disease (COPD due to premature cellular senescence and exhaustion of the regenerative potential of the muscles. METHODS: Vastus lateralis biopsies were obtained from patients with COPD (n = 16 and healthy subjects (n = 7. Satellite cell number and the proportion of central nuclei, as a marker of muscle regenerative events, were assessed on cryosections. Telomere lengths, used as a marker of cellular senescence, were determined using Southern blot analyses. RESULTS: Central nuclei proportion was significantly higher in patients with COPD with a preserved muscle mass compared to controls and patients with COPD with muscle atrophy (p<0.001. In COPD, maximal telomere length was significantly decreased compared to controls (p<0.05. Similarly, minimal telomere length was significantly reduced in GOLD III-IV patients with muscle atrophy compared to controls (p<0.005. Minimal, mean and maximum telomere lengths correlated with mid-thigh muscle cross-sectional area (MTCSA (R = 0.523, p = 0.005; R = 0.435, p = 0.019 and R = 0.491, p = 0.009, respectively. CONCLUSIONS: Evidence of increased regenerative events was seen in GOLD III-IV patients with preserved muscle mass. Shortening of telomeres in GOLD III-IV patients with muscle atrophy is consistent with an increased number of senescent satellite cells and an exhausted muscle regenerative capacity, compromising the maintenance of muscle mass in these individuals.

  8. Label-free screening of niche-to-niche variation in satellite stem cells using functionalized pores

    Science.gov (United States)

    Chapman, Matthew R.; Balakrishnan, Karthik; Conboy, Michael J.; Mohanty, Swomitra; Jabart, Eric; Huang, Haiyan; Hack, James; Conboy, Irina M.; Sohn, Lydia L.

    2012-02-01

    Combinations of surface markers are currently used to identify muscle satellite cells. Using pores functionalized with specific antibodies and measuring the transit time of cells passing through these pores, we discovered remarkable heterogeneity in the expression of these markers in muscle (satellite) stem cells that reside in different single myofibers. Microniche-specific variation in stem cells of the same organ has not been previously described, as bulk analysis does not discriminate between separate myofibers or even separate hind-leg muscle groups. We found a significant population of Sca-1+ satellite cells that form myotubes, thereby demonstrating the myogenic potential of Sca-1+ cells, which are currently excluded in bulk sorting. Finally, using our label-free pore screening technique, we have been able to quantify directly surface expression of Notch1 without activation of the Notch pathway. We show for the first time Notch1-expression heterogeneity in unactivated satellite cells. The discovery of fiber-to-fiber variations prompts new research into the reasons for such diversity in muscle stem cells.

  9. Circularly Polarized Transparent Microstrip Patch Reflectarray Integrated with Solar Cell for Satellite Applications

    Directory of Open Access Journals (Sweden)

    S. H. Zainud-Deen

    2016-01-01

    Full Text Available Circularly polarized (CP transparent microstrip reflectarray antenna is integrated with solar cell for small satellite applications at 10 GHz. The reflectarray unit cell consists of a perfect electric conductor (PEC square patch printed on an optically transparent substrate with the PEC ground plane. A comparison between using transparent conducting polymers and using the PEC in unit-cell construction has been introduced. The waveguide simulator is used to calculate the required compensation phase of each unit cell in the reflectarray. The radiation characteristics of 13 × 13 CP transparent reflectarray antenna are investigated. A circularly polarized horn antenna is used to feed the reflectarray. The solar cell is incorporated with the transparent reflectarray on the same area. The solar-cell integration with the reflectarray reduces the maximum gain by about 0.5 dB due to the increase in the magnitude of the reflection coefficient. The results are calculated using the finite integral technique (FIT.

  10. Study on Cell Error Rate of a Satellite ATM System Based on CDMA

    Institute of Scientific and Technical Information of China (English)

    赵彤宇; 张乃通

    2003-01-01

    In this paper, the cell error rate (CER) of a CDMA-based satellite ATM system is analyzed. Two fading models, i.e. the partial fading model and the total fading model are presented according to multi-path propagation fading and shadow effect. Based on the total shadow model, the relation of CER vs. the number of subscribers at various elevations under 2D-RAKE receiving and non-diversity receiving is got. The impact on cell error rate with pseudo noise (PN) code length is also considered. The result that the maximum likelihood combination of multi-path signal would not improve the system performance when multiple access interference (MAI) is small, on the contrary the performance may be even worse is abtained.

  11. Potential Role of Omega-3 Fatty Acids on the Myogenic Program of Satellite Cells.

    Science.gov (United States)

    Bhullar, Amritpal S; Putman, Charles T; Mazurak, Vera C

    2016-01-01

    Skeletal muscle loss is associated with aging as well as pathological conditions. Satellite cells (SCs) play an important role in muscle regeneration. Omega-3 fatty acids are widely studied in a variety of muscle wasting diseases; however, little is known about their impact on skeletal muscle regeneration. The aim of this review is to evaluate studies examining the effect of omega-3 fatty acids, α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid on the regulation of SC proliferation and differentiation. This review highlights mechanisms by which omega-3 fatty acids may modulate the myogenic program of the stem cell population within skeletal muscles and identifies considerations for future studies. It is proposed that minimally three myogenic transcriptional regulatory factors, paired box 7 (Pax7), myogenic differentiation 1 protein, and myogenin, should be measured to confirm the stage of SCs within the myogenic program affected by omega-3 fatty acids.

  12. Communication between neuronal somata and satellite glial cells in sensory ganglia.

    Science.gov (United States)

    Huang, Li-Yen M; Gu, Yanping; Chen, Yong

    2013-10-01

    Studies of the structural organization and functions of the cell body of a neuron (soma) and its surrounding satellite glial cells (SGCs) in sensory ganglia have led to the realization that SGCs actively participate in the information processing of sensory signals from afferent terminals to the spinal cord. SGCs use a variety ways to communicate with each other and with their enwrapped soma. Changes in this communication under injurious conditions often lead to abnormal pain conditions. "What are the mechanisms underlying the neuronal soma and SGC communication in sensory ganglia?" and "how do tissue or nerve injuries affect the communication?" are the main questions addressed in this review. Copyright © 2013 Wiley Periodicals, Inc.

  13. Optimized High Temperature PEM Fuel Cell & High Pressure PEM Electrolyser for Regenerative Fuel Cell Systems in GEO Telecommunication Satellites

    Directory of Open Access Journals (Sweden)

    Farnes Jarle

    2017-01-01

    Full Text Available Next generation telecommunication satellites will demand increasingly more power. Power levels up to 50 kW are foreseen for the next decades. Battery technology that can sustain up to 50 kW for eclipse lengths of up to 72 minutes will represent a major impact on the total mass of the satellite, even with new Li-ion battery technologies. Regenerative fuel cell systems (RFCS were identified years ago as a possible alternative to rechargeable batteries. CMR Prototech has investigated this technology in a series of projects initiated by ESA focusing on both the essential fuel cell technology, demonstration of cycle performance of a RFCS, corresponding to 15 years in orbit, as well as the very important reactants storage systems. In the last two years the development has been focused towards optimising the key elements of the RFCS; the HTPEM fuel cell and the High Pressure PEM electrolyser. In these ESA activities the main target has been to optimise the design by reducing the mass and at the same time improve the performance, thus increasing the specific energy. This paper will present the latest development, including the main results, showing that significant steps have been taken to increase TRL on these key components.

  14. Satellite cell heterogeneity revealed by G-Tool, an open algorithm to quantify myogenesis through colony-forming assays

    Directory of Open Access Journals (Sweden)

    Ippolito Joseph

    2012-06-01

    Full Text Available Abstract Background Muscle growth and repair is accomplished by the satellite cell pool, a self-renewing population of myogenic progenitors. Functional heterogeneity within the satellite cell compartment and changes in potential with experimental intervention can be revealed by in vitro colony-forming cell (CFC assays, however large numbers of colonies need to be assayed to give meaningful data, and manually quantifying nuclei and scoring markers of differentiation is experimentally limiting. Methods We present G-Tool, a multiplatform (Java open-source algorithm that analyzes an ensemble of fluorescent micrographs of satellite cell-derived colonies to provide quantitative and statistically meaningful metrics of myogenic potential, including proliferation capacity and propensity to differentiate. Results We demonstrate the utility of G-Tool in two applications: first, we quantify the response of satellite cells to oxygen concentration. Compared to 3% oxygen which approximates tissue levels, we find that 21% oxygen, the ambient level, markedly limits the proliferative potential of transit amplifying progeny but at the same time inhibits the rate of terminal myogenic differentiation. We also test whether satellite cells from different muscles have intrinsic differences that can be read out in vitro. Compared to masseter, dorsi, forelimb and hindlimb muscles, we find that the diaphragm satellite cells have significantly increased proliferative potential and a reduced propensity to spontaneously differentiate. These features may be related to the unique always-active status of the diaphragm. Conclusions G-Tool facilitates consistent and reproducible CFC analysis between experiments and individuals. It is released under an open-source license that enables further development by interested members of the community.

  15. Development of a nitric oxide-releasing analogue of the muscle relaxant guaifenesin for skeletal muscle satellite cell myogenesis.

    Science.gov (United States)

    Wang, Guqi; Burczynski, Frank J; Hasinoff, Brian B; Zhang, Kaidong; Lu, Qilong; Anderson, Judy E

    2009-01-01

    Nitric oxide (NO) mediates activation of satellite precursor cells to enter the cell cycle. This provides new precursor cells for skeletal muscle growth and muscle repair from injury or disease. Targeting a new drug that specifically delivers NO to muscle has the potential to promote normal function and treat neuromuscular disease, and would also help to avoid side effects of NO from other treatment modalities. In this research, we examined the effectiveness of the NO donor, iosorbide dinitrate (ISDN), and a muscle relaxant, methocarbamol, in promoting satellite cell activation assayed by muscle cell DNA synthesis in normal adult mice. The work led to the development of guaifenesin dinitrate (GDN) as a new NO donor for delivering nitric oxide to muscle. The results revealed that there was a strong increase in muscle satellite cell activation and proliferation, demonstrated by a significant 38% rise in DNA synthesis after a single transdermal treatment with the new compound for 24 h. Western blot and immunohistochemistry analyses showed that the markers of satellite cell myogenesis, expression of myf5, myogenin, and follistatin, were increased after 24 h oral administration of the compound in adult mice. This research extends our understanding of the outcomes of NO-based treatments aimed at promoting muscle regeneration in normal tissue. The potential use of such treatment for conditions such as muscle atrophy in disuse and aging, and for the promotion of muscle tissue repair as required after injury or in neuromuscular diseases such as muscular dystrophy, is highlighted.

  16. Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training

    DEFF Research Database (Denmark)

    Olsen, Steen Schytte

    2006-01-01

    The present study investigated the influence of creatine and protein supplementation on satellite cell frequency and number of myonuclei in human skeletal muscle during 16 weeks of heavy-resistance training. In a double-blinded design 32 healthy, male subjects (19–26 years) were assigned...... in the control group (CON). In conclusion, the present study demonstrates for the first time that creatine supplementation in combination with strength training amplifies the training-induced increase in satellite cell number and myonuclei concentration in human skeletal muscle fibres, thereby allowing......). Furthermore, timed protein/placebo intake were administered at all training sessions. Muscle biopsies were obtained at week 0, 4, 8 (week 8 not CON) and 16 of resistance training (3 days per week). Satellite cells were identified by immunohistochemistry. Muscle mean fibre (MFA) area was determined after...

  17. MicroRNA-133 Controls Brown Adipose Determination in Skeletal Muscle Satellite Cells by Targeting Prdm16

    DEFF Research Database (Denmark)

    Yin, Hang; Pasut, Alessandra; Soleimani, Vahab D

    2013-01-01

    (satellite cells) have long been considered uniformly determined toward the myogenic lineage. Here, we report that adult satellite cells give rise to brown adipocytes and that microRNA-133 regulates the choice between myogenic and brown adipose determination by targeting the 3'UTR of Prdm16. Antagonism...... are downregulated in mice exposed to cold, resulting in de novo generation of satellite cell-derived brown adipocytes. Therefore, microRNA-133 represents an important therapeutic target for the treatment of obesity....... of microRNA-133 during muscle regeneration increases uncoupled respiration, glucose uptake, and thermogenesis in local treated muscle and augments whole-body energy expenditure, improves glucose tolerance, and impedes the development of diet-induced obesity. Finally, we demonstrate that miR-133 levels...

  18. Satellite cell activity is differentially affected by contraction mode in human muscle following a work-matched bout of exercise

    Directory of Open Access Journals (Sweden)

    Robert D Hyldahl

    2014-12-01

    Full Text Available Optimal repair and adaptation of skeletal muscle is facilitated by resident stem cells (satellite cells. To understand how different exercise modes influence satellite cell dynamics, we measured satellite cell activity in conjunction with markers of muscle damage and inflammation in human skeletal muscle following a single work- and intensity-matched bout of eccentric (ECC or concentric contractions (CON. Participants completed a single bout of ECC (n=7 or CON (n=7 of the knee extensors. A muscle biopsy was obtained before and 24 h after exercise. Functional measures and immunohistochemical analyses were used to determine the extent of muscle damage and indices of satellite cell activity. Cytokine concentrations were measured using a multiplexed magnetic bead assay. Isokinetic peak torque decreased following ECC (p<0.05 but not CON. Greater histological staining of the damage marker Xin was observed in muscle samples of ECC vs CON. Tenasin C immunoreactivity increased 15 fold (P<0.01 following ECC and was unchanged following CON. The inflammatory cytokines interferon gamma-induced protein 10 (IP-10 and monocyte chemotactic protein 1 (MCP-1 increased pre- to post-ECC (4.26 ± 1.4 vs. 10.49 ± 5.8 pg/ml, and 3.06 ± 0.7 vs. 6.25 ± 4.6 pg/ml, respectively; p<0.05. There was no change in any cytokine post-CON. Satellite cell content increased 27% pre- to post-ECC (0.10 ± 0.031 vs. 0.127 ± 0.041, respectively; p<0.05. There was no change in satellite cell number in CON (0.099 ± 0.027 vs. 0.102 ± 0.029, respectively. There was no fiber type-specific satellite cell response following either exercise mode. ECC but not CON resulted in an increase in MyoD positive nuclei per myofiber pre- to post-exercise (p<0.05, but there was no change in MyoD DNA binding activity in either condition. In conclusion, ECC but not CON results in functional and histological evidence of muscle damage that is accompanied by increased satellite cell activity 24 h post-exercise.

  19. Molecular and functional heterogeneity of early postnatal porcine satellite cell populations is associated with bioenergetic profile

    Science.gov (United States)

    Miersch, Claudia; Stange, Katja; Hering, Silvio; Kolisek, Martin; Viergutz, Torsten; Röntgen, Monika

    2017-01-01

    During postnatal development, hyperplastic and hypertrophic processes of skeletal muscle growth depend on the activation, proliferation, differentiation, and fusion of satellite cells (SC). Therefore, molecular and functional SC heterogeneity is an important component of muscle plasticity and will greatly affect long-term growth performance and muscle health. However, its regulation by cell intrinsic and extrinsic factors is far from clear. In particular, there is only minor information on the early postnatal period which is critical for muscle maturation and the establishment of adult SC pools. Here, we separated two SC subpopulations (P40/50, P50/70) from muscle of 4-day-old piglets. Our results characterize P40/50 as homogeneous population of committed (high expression of Myf5), fast-proliferating muscle progenitors. P50/70 constituted a slow-proliferating phenotype and contains high numbers of differentiated SC progeny. During culture, P50/70 is transformed to a population with lower differentiation potential that contains 40% Pax7-positive cells. A reversible state of low mitochondrial activity that results from active down-regulation of ATP-synthase is associated with the transition of some of the P50/70 cells to this more primitive fate typical for a reserve cell population. We assume that P40/50 and P50/70 subpopulations contribute unequally in the processes of myofiber growth and maintenance of the SC pool. PMID:28344332

  20. Adapted physical exercise enhances activation and differentiation potential of satellite cells in the skeletal muscle of old mice.

    Science.gov (United States)

    Cisterna, Barbara; Giagnacovo, Marzia; Costanzo, Manuela; Fattoretti, Patrizia; Zancanaro, Carlo; Pellicciari, Carlo; Malatesta, Manuela

    2016-05-01

    During ageing, a progressive loss of skeletal muscle mass and a decrease in muscle strength and endurance take place, in the condition termed sarcopenia. The mechanisms of sarcopenia are complex and still unclear; however, it is known that muscle atrophy is associated with a decline in the number and/or efficiency of satellite cells, the main contributors to muscle regeneration. Physical exercise proved beneficial in sarcopenia; however, knowledge of the effect of adapted physical exercise on the myogenic properties of satellite cells in aged muscles is limited. In this study the amount and activation state of satellite cells as well as their proliferation and differentiation potential were assessed in situ by morphology, morphometry and immunocytochemistry at light and transmission electron microscopy on 28-month-old mice submitted to adapted aerobic physical exercise on a treadmill. Sedentary age-matched mice served as controls, and sedentary adult mice were used as a reference for an unperturbed control at an age when the capability of muscle regeneration is still high. The effect of physical exercise in aged muscles was further analysed by comparing the myogenic potential of satellite cells isolated from old running and old sedentary mice using an in vitro system that allows observation of the differentiation process under controlled experimental conditions. The results of this ex vivo and in vitro study demonstrated that adapted physical exercise increases the number and activation of satellite cells as well as their capability to differentiate into structurally and functionally correct myotubes (even though the age-related impairment in myotube formation is not fully reversed): this evidence further supports adapted physical exercise as a powerful, non-pharmacological approach to counteract sarcopenia and the age-related deterioration of satellite cell capabilities even at very advanced age.

  1. Satellite cell activation in stretched skeletal muscle and the role of nitric oxide and hepatocyte growth factor.

    Science.gov (United States)

    Tatsumi, Ryuichi; Liu, Xiaosong; Pulido, Antonio; Morales, Mark; Sakata, Tomowa; Dial, Sharon; Hattori, Akihito; Ikeuchi, Yoshihide; Allen, Ronald E

    2006-06-01

    In the present study, we examined the roles of hepatocyte growth factor (HGF) and nitric oxide (NO) in the activation of satellite cells in passively stretched rat skeletal muscle. A hindlimb suspension model was developed in which the vastus, adductor, and gracilis muscles were subjected to stretch for 1 h. Satellite cells were activated by stretch determined on the basis of 5-bromo-2'-deoxyuridine (BrdU) incorporation in vivo. Extracts from stretched muscles stimulated BrdU incorporation in freshly isolated control rat satellite cells in a concentration-dependent manner. Extracts from stretched muscles contained the active form of HGF, and the satellite cell-activating activity could be neutralized by incubation with anti-HGF antibody. The involvement of NO was investigated by administering nitro-L-arginine methyl ester (L-NAME) or the inactive enantiomer N(G)-nitro-D-arginine methyl ester HCl (D-NAME) before stretch treatment. In vivo activation of satellite cells in stretched muscle was not inhibited by D-NAME but was inhibited by L-NAME. The activity of stretched muscle extract was abolished by L-NAME treatment but could be restored by the addition of HGF, indicating that the extract was not inhibitory. Finally, NO synthase activity in stretched and unstretched muscles was assayed in muscle extracts immediately after 2-h stretch treatment and was found to be elevated in stretched muscle but not in stretched muscle from L-NAME-treated rats. The results of these experiments demonstrate that stretching muscle liberates HGF in a NO-dependent manner, which can activate satellite cells.

  2. Mixed lactate and caffeine compound increases satellite cell activity and anabolic signals for muscle hypertrophy.

    Science.gov (United States)

    Oishi, Yoshimi; Tsukamoto, Hayato; Yokokawa, Takumi; Hirotsu, Keisuke; Shimazu, Mariko; Uchida, Kenji; Tomi, Hironori; Higashida, Kazuhiko; Iwanaka, Nobumasa; Hashimoto, Takeshi

    2015-03-15

    We examined whether a mixed lactate and caffeine compound (LC) could effectively elicit proliferation and differentiation of satellite cells or activate anabolic signals in skeletal muscles. We cultured C2C12 cells with either lactate or LC for 6 h. We found that lactate significantly increased myogenin and follistatin protein levels and phosphorylation of P70S6K while decreasing the levels of myostatin relative to the control. LC significantly increased protein levels of Pax7, MyoD, and Ki67 in addition to myogenin, relative to control. LC also significantly increased follistatin expression relative to control and stimulated phosphorylation of mTOR and P70S6K. In an in vivo study, male F344/DuCrlCrlj rats were assigned to control (Sed, n = 10), exercise (Ex, n = 12), and LC supplementation (LCEx, n = 13) groups. LC was orally administered daily. The LCEx and Ex groups were exercised on a treadmill, running for 30 min at low intensity every other day for 4 wk. The LCEx group experienced a significant increase in the mass of the gastrocnemius (GA) and tibialis anterior (TA) relative to both the Sed and Ex groups. Furthermore, the LCEx group showed a significant increase in the total DNA content of TA compared with the Sed group. The LCEx group experienced a significant increase in myogenin and follistatin expression of GA relative to the Ex group. These results suggest that administration of LC can effectively increase muscle mass concomitant with elevated numbers of myonuclei, even with low-intensity exercise training, via activated satellite cells and anabolic signals. Copyright © 2015 the American Physiological Society.

  3. Defining a role for non-satellite stem cells in the regulation of muscle repair following exercise

    Directory of Open Access Journals (Sweden)

    Marni D. Boppart

    2013-11-01

    Full Text Available Skeletal muscle repair is essential for effective remodeling, tissue maintenance, and initiation of beneficial adaptations post-eccentric exercise. A series of well characterized events, such as recruitment of immune cells and activation of satellite cells, constitute the basis for muscle regeneration. However, details regarding the fine-tuned regulation of this process in response to different types of injury are open for investigation. Muscle-resident non-myogenic, non-satellite stem cells expressing conventional mesenchymal stem cell (MSC markers, have the potential to significantly contribute to regeneration given the role for bone marrow-derived MSCs in whole body tissue repair in response to injury and disease. The purpose of this mini-review is to highlight a regulatory role for non-satellite stem cells in the process of skeletal muscle healing post-eccentric exercise. The non-myogenic, non-satellite stem cell fraction will be defined, its role in tissue repair will be briefly reviewed, and recent studies demonstrating a contribution to eccentric exercise-induced regeneration will be presented.  

  4. Boron doped Si rich oxide/SiO{sub 2} and silicon rich nitride/SiN{sub x} bilayers on molybdenum-fused silica substrates for vertically structured Si quantum dot solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Ziyun, E-mail: z.lin@unsw.edu.au; Wu, Lingfeng; Jia, Xuguang; Zhang, Tian; Puthen-Veettil, Binesh; Yang, Terry Chien-Jen; Conibeer, Gavin; Perez-Wurfl, Ivan [School of Photovoltaic and Renewable Energy Engineering, University of New South Wales, Building H6, Tyree Energy Technologies Building, Kensington, New South Wales 2052 (Australia)

    2015-07-28

    Vertically structured Si quantum dots (QDs) solar cells with molybdenum (Mo) interlayer on quartz substrates would overcome current crowding effects found in mesa-structured cells. This study investigates the compatibility between boron (B) doped Si QDs bilayers and Mo-fused silica substrate. Both Si/SiO{sub 2} and Si/SiN{sub x} based QDs bilayers were studied. The material compatibility under high temperature treatment was assessed by examining Si crystallinity, microstress, thin film adhesion, and Mo oxidation. It was observed that the presence of Mo interlayer enhanced the Si QDs size confinement, crystalline fraction, and QDs size uniformity. The use of B doping was preferred compared to phosphine (PH{sub 3}) doping studied previously in terms of better surface and interface properties by reducing oxidized spots on the film. Though crack formation due to thermal mismatch after annealing remained, methods to overcome this problem were proposed in this paper. Schematic diagram to fabricate full vertical structured Si QDs solar cells was also suggested.

  5. MicroRNA-128 regulates the proliferation and differentiation of bovine skeletal muscle satellite cells by repressing Sp1.

    Science.gov (United States)

    Dai, Yang; Zhang, Wei Ran; Wang, Yi Min; Liu, Xin Feng; Li, Xin; Ding, Xiang Bin; Guo, Hong

    2016-03-01

    MicroRNAs (miRNAs) play essential roles in muscle cell proliferation and differentiation. The muscle-specific miRNAs miR-1 and miR-206 have been shown to regulate muscle development and promote myogenic differentiation; however, it is likely that a number of other miRNAs play important roles in regulating myogenesis as well. microRNA-128 (miR-128) has been reported to be highly expressed in brain and skeletal muscle, and we found that miR-128 is also up-regulated during bovine skeletal muscle satellite cell differentiation using microarray analysis and qRT-PCR. However, little is known about the functions of miR-128 in bovine skeletal muscle satellite cell development. In this study, we investigated the biological functions of miR-128 in bovine skeletal muscle cell development. Using a dual-luciferase reporter assay, we confirmed that miR-128 regulates the Sp1 gene. Over-expression of miR-128 reduced Sp1 protein levels and inhibited muscle satellite cell proliferation and differentiation. Inhibition of miR-128 increased Sp1 protein levels and promoted muscle satellite cell differentiation but also suppressed proliferation. Changes in miR-128 and Sp1 expression levels also affected the protein levels of MyoD and CDKN1A. Sp1, an activator of MyoD and a suppressor of CDKN1A, plays an important role in bovine muscle cell proliferation and differentiation. The results of our study reveal a mechanism by which miR-128 regulates bovine skeletal muscle satellite cell proliferation and myogenic differentiation via Sp1.

  6. Micro space power system using MEMS fuel cell for nano-satellites

    Science.gov (United States)

    Lee, Jongkwang; Kim, Taegyu

    2014-08-01

    A micro space power system using micro fuel cell was developed for nano-satellites. The power system was fabricated using microelectromechanical system (MEMS) fabrication technologies. Polymer electrolyte membrane (PEM) fuel cell was selected in consideration of space environment. Sodium borohydride (NaBH4) was selected as a hydrogen source while hydrogen peroxide (H2O2) was selected as an oxygen source. The power system consists of a micro fuel cell, micro-reactor, micro-pump, and fuel cartridges. The micro fuel cell was fabricated on a light-weight and corrosion-resistant glass plates. The micro-reactor was used to generate hydrogen from NaBH4 alkaline solution via a catalytic hydrolysis reaction. All components such as micro-pump, fuel cartridges, and auxiliary battery were integrated for a complete power system. The storability of NaBH4 solution was evaluated at -25 °C and the performance of the micro power system was measured at various operating conditions. The power output of micro power system reasonably followed up the given electric load conditions.

  7. The differential proliferative ability of satellite cells in Lantang and Landrace pigs.

    Science.gov (United States)

    Wang, Xiu-qi; Yang, Wei-jun; Yang, Zhou; Shu, Gang; Wang, Song-bo; Jiang, Qing-yan; Yuan, Li; Wu, Tong-shan

    2012-01-01

    Here, for the first time, we evaluate the hypothesis that the proliferative abilities of satellite cells (SCs) isolated from Lantang (indigenous Chinese pigs) and Landrace pigs, which differ in muscle characteristics, are different. SCs were isolated from the longissimus dorsi muscle of neonatal Lantang and Landrace pigs. Proliferative ability was estimated by the count and proliferative activity of viable cells using a hemocytometer and MTT assay at different time points after seeding, respectively. Cell cycle information was detected by flow cytometry. Results showed that there was a greater (PLandrace pigs after 72 h of culture. The percentage of cell population in S phase and G(2)/M phases in Lantang pigs were higher (PLandrace pigs. The mRNA abundances of MyoD, Myf5, myogenin and Pax7 in SCs from Lantang pigs were higher (PLandrace pigs. Protein levels of MyoD, myogenin, myostatin, S6K, phosphorylated mTOR and phosphorylated eIF4E were consistent with the corresponding mRNA abundance. Collectively, these findings suggested that SCs in the two breeds present different proliferative abilities, and the proliferative potential of SCs in Lantang pigs is higher than in Landrace pigs.

  8. Skeletal muscle satellite cells: mediators of muscle growth during development and implications for developmental disorders.

    Science.gov (United States)

    Dayanidhi, Sudarshan; Lieber, Richard L

    2014-11-01

    Satellite cells (SCs) are the muscle stem cells responsible for longitudinal and cross-sectional postnatal growth and repair after injury and which provide new myonuclei when needed. We review their morphology and contribution to development and their role in sarcomere and myonuclear addition. SCs, similar to other tissue stem cells, cycle through different states, such as quiescence, activation, and self-renewal, and thus we consider the signaling mechanisms involved in maintenance of these states. The role of the SC niche and their interactions with other cells, such as fibroblasts and the extracellular matrix, are all emerging as major factors that affect aging and disease. Interestingly, children with cerebral palsy appear to have a reduced SC number, which could play a role in their reduced muscular development and even in muscular contracture formation. Finally, we review the current information on SC dysfunction in children with muscular dystrophy and emerging therapies that target promotion of myogenesis and reduction of fibrosis. © 2014 Wiley Periodicals, Inc.

  9. About a New Type of Fuse Based on the Controllable Fusing Effect

    Directory of Open Access Journals (Sweden)

    PLESCA, A.

    2009-06-01

    Full Text Available Fuses are among the best known of electrical devices and there are an extremely large number in use throughout the world. Beside of the advantageous features, the nowadays fuses have certain drawbacks. Therefore, a new type of fuse based on controllable fusing concept is proposed and a study as regards the total clearing time is done. The new concept has been validated through many experimental tests at different current values. The new type of fuse based on controllable fusing concept can be integrated within an overcurrent protection system especially to protect power semiconductors where the Joule integral criterion is better satisfied.

  10. Plane of nutrition affects growth rate, organ size and skeletal muscle satellite cell activity in newborn calves.

    Science.gov (United States)

    MacGhee, M E; Bradley, J S; McCoski, S R; Reeg, A M; Ealy, A D; Johnson, S E

    2016-11-18

    Plane of nutrition effects on body, tissue and cellular growth in the neonatal calf are poorly understood. The hypothesis that a low plane of nutrition (LPN) would limit skeletal muscle size by reducing fibre growth and muscle progenitor cell activity was tested. At birth, calves were randomly assigned to either a LPN (20% CP, 20% fat; GE=1.9 Mcal/days) or a high plane of nutrition (HPN; 27% CP, 10% fat, GE = 3.8 Mcal/days) in a 2 × 3 factorial design to test the impact of diet on neonatal calf growth, organ weight and skeletal muscle morphometry with time. Groups of calves (n = 4 or 5) were euthanised at 2, 4 and 8 week of age and organ and empty carcass weights were recorded. Body composition was measured by DXA. Longissimus muscle (LM) fibre cross-sectional area (CSA), fibre/mm(2) and Pax7 were measured by immunohistology. Satellite cells were isolated at each time point and proliferation rates were measured by EdU incorporation. Calves fed a HPN had greater (p satellite cells per fibre. Proliferation rates of satellite cells isolated from HPN fed calves were greater (p satellite cell activity.

  11. Muscle Fiber Characteristics, Satellite Cells and Soccer Performance in Young Athletes

    Directory of Open Access Journals (Sweden)

    Thomas I. Metaxas, Athanasios Mandroukas, Efstratios Vamvakoudis, Kostas Kotoglou, Björn Ekblom, Konstantinos Mandroukas

    2014-09-01

    Full Text Available This study is aimed to examine the muscle fiber type, composition and satellite cells in young male soccer players and to correlate them to cardiorespiratory indices and muscle strength. The participants formed three Groups: Group A (n = 13, 11.2 ± 0.4yrs, Group B (n=10, 13.1 ± 0.5yrs and Group C (n = 9, 15.2 ± 0.6yrs. Muscle biopsies were obtained from the vastus lateralis. Peak torque values of the quadriceps and hamstrings were recorded and VO2max was measured on the treadmill. Group C had lower type I percentage distribution compared to A by 21.3% (p < 0.01, while the type IIA relative percentage was higher by 18.1% and 18.4% than in Groups A and B (p < 0.05. Groups B and C had higher cross-sectional area (CSA values in all fiber types than in Group A (0.05 < p < 0.001. The number of satellite cells did not differ between the groups. Groups B and C had higher peak torque at all angular velocities and absolute VO2max in terms of ml·min-1 than Group A (0.05 < p < 0.001. It is concluded that the increased percentage of type IIA muscle fibers noticed in Group C in comparison to the Groups A and B should be mainly attributed to the different workload exercise and training programs. The alteration of myosin heavy chain (MHC isoforms composition even in children is an important mechanism for skeletal muscle characteristics. Finally, CSA, isokinetic muscle strength and VO2max values seems to be expressed according to age.

  12. Dynamic simulation of flywheel-type fuses

    OpenAIRE

    Editorial Office

    1996-01-01

    Rounds of ammunition are normally armed with a fuse. In this study, a fuse is developed which uses a flywheel-type mechanism controlled by time or distance. Due to its simplicity of operation and construction, the concept is expected to have high reliabil­ity. The dynamic response of all the components of this flywheel-type fuse is mathematically modelled. Simulation software was developed which connects the mathematical models of the various components. With the definition of boundary value...

  13. Generation of human muscle fibers and satellite-like cells from human pluripotent stem cells in vitro.

    Science.gov (United States)

    Chal, Jérome; Al Tanoury, Ziad; Hestin, Marie; Gobert, Bénédicte; Aivio, Suvi; Hick, Aurore; Cherrier, Thomas; Nesmith, Alexander P; Parker, Kevin K; Pourquié, Olivier

    2016-10-01

    Progress toward finding a cure for muscle diseases has been slow because of the absence of relevant cellular models and the lack of a reliable source of muscle progenitors for biomedical investigation. Here we report an optimized serum-free differentiation protocol to efficiently produce striated, millimeter-long muscle fibers together with satellite-like cells from human pluripotent stem cells (hPSCs) in vitro. By mimicking key signaling events leading to muscle formation in the embryo, in particular the dual modulation of Wnt and bone morphogenetic protein (BMP) pathway signaling, this directed differentiation protocol avoids the requirement for genetic modifications or cell sorting. Robust myogenesis can be achieved in vitro within 1 month by personnel experienced in hPSC culture. The differentiating culture can be subcultured to produce large amounts of myogenic progenitors amenable to numerous downstream applications. Beyond the study of myogenesis, this differentiation method offers an attractive platform for the development of relevant in vitro models of muscle dystrophies and drug screening strategies, as well as providing a source of cells for tissue engineering and cell therapy approaches.

  14. Enhancement of cytotoxic T lymphocyte activity by dendritic cells loaded with Tat-protein transduction domain-fused hepatitis B virus core antigen

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The protein transduction domain (PTD) of human immuno-deficiency virus-1-Tat protein has a unique potency to pen-etrate the cellular membranes. To synthesize the sequence of Tat-PTD and hepatitis B virus core antigen (HBcAg), we spliced these sequences and linked a fusion gene into the pMAL-c2x vector. The fusion proteins were purified by affin-ity chromatography and pulsed with bone marrow -derived den-dritic cells (DCs), and the transduction of recombinant pro-tein was detected by immunofluorescence antibody assay.Results showed that recombinant PTD-HBcAg could pen-etrate into DC cytoplasm while recombinant HBcAg was de-tected on the surface of cells. The percentage of DC surface molecules, such as CD80, CD86 and major histocompatibii-ity complex Ⅱ, and production of cytokine (IL-12pT0) induced by recombinant PTD-HBcAg were significantly higher than those induced by recombinant HBcAg or tumor necrosis fac-tor-α. DCs treated with PTD-HBcAg induced T cells to dif-ferentiate into specific cytotoxic T lymphocytes (CTLs) and enhanced the CTL killing response. In conclusion, the ex-pressed and purified PTD-HBcAg fusion protein could pen-etrate into cells through the plasma membrane, promote DC maturation, and enhance T cells response to generate HBcAg-specific CTLs efficiently.

  15. Analytical study of pulsed laser irradiation on some materials used for photovoltaic cells on satellites

    Directory of Open Access Journals (Sweden)

    Afaf M. Abd El-Hameed

    2015-12-01

    Full Text Available The present research concerns on the study of laser-powered solar panels used for space applications. A mathematical model representing the laser effects on semiconductors has been developed. The temperature behavior and heat flow on the surface and through a slab has been studied after exposed to nano-second pulsed laser. The model is applied on two different types of common active semiconductor materials that used for photovoltaic cells fabrication as silicon (Si, and gallium arsenide (GaAs. These materials are used for receivers’ manufacture for laser beamed power in space. Various values of time are estimated to clarify the heat flow through the material sample and generated under the effects of pulsed laser irradiation. These effects are theoretically studied in order to determine the performance limits of the solar cells when they are powered by laser radiation during the satellite eclipse. Moreover, the obtained results are carried out to optimize conversion efficiency of photovoltaic cells and may be helpful to give more explanation for layout of the light-electricity space systems.

  16. Skeletal muscle satellite cells, mitochondria and microRNAs: their involvement in the pathogenesis of ALS

    Directory of Open Access Journals (Sweden)

    Stavroula Tsitkanou

    2016-09-01

    Full Text Available Amyotrophic lateral sclerosis (ALS, also known as motor neurone disease (MND, is a fatal motor neurone disorder. It results in progressive degeneration and death of upper and lower motor neurones, protein aggregation, severe muscle atrophy and respiratory insufficiency. Median survival with ALS is between two to five years from the onset of symptoms. ALS manifests as either familial ALS (FALS (~10% of cases or sporadic ALS (SALS, (~90% of cases. Mutations in the copper/zinc (CuZn superoxide dismutase (SOD1 gene account for ~20% of FALS cases and the mutant SOD1 mouse model has been used extensively to help understand the ALS pathology. As the precise mechanisms causing ALS are not well understood there is presently no cure. Recent evidence suggests that motor neuron degradation may involve a cell non-autonomous phenomenon involving numerous cell types within various tissues. Skeletal muscle is now considered as an important tissue involved in the pathogenesis of ALS by activating a retrograde signalling cascade that degrades motor neurons. Skeletal muscle heath and function are regulated by numerous factors including satellite cells, mitochondria and microRNAs. Studies demonstrate that in ALS these factors show various levels of dysregulation within the skeletal muscle. This review provides an overview of their dysregulation in various ALS models as well as how they may contribute individually and/or synergistically to the ALS pathogenesis.

  17. Analytical study of pulsed laser irradiation on some materials used for photovoltaic cells on satellites

    Science.gov (United States)

    Abd El-Hameed, Afaf M.

    2015-12-01

    The present research concerns on the study of laser-powered solar panels used for space applications. A mathematical model representing the laser effects on semiconductors has been developed. The temperature behavior and heat flow on the surface and through a slab has been studied after exposed to nano-second pulsed laser. The model is applied on two different types of common active semiconductor materials that used for photovoltaic cells fabrication as silicon (Si), and gallium arsenide (GaAs). These materials are used for receivers' manufacture for laser beamed power in space. Various values of time are estimated to clarify the heat flow through the material sample and generated under the effects of pulsed laser irradiation. These effects are theoretically studied in order to determine the performance limits of the solar cells when they are powered by laser radiation during the satellite eclipse. Moreover, the obtained results are carried out to optimize conversion efficiency of photovoltaic cells and may be helpful to give more explanation for layout of the light-electricity space systems.

  18. FUSE Observations of eta Carinae

    CERN Document Server

    Iping, R C; Gull, T R

    2004-01-01

    Eta Carinae was observed by FUSE through the LWRS (30 arcsec x30 arcsec) and HIRS (1.25 arcsec x 20 arcsec) apertures in March and April 2004. There are significant differences between the two spectra. About half of the LWRS flux appears to be due to two B-type stars near the edge of the LWRS aperture, 14 arcsec from eta Carinae. The HIRS spectrum (LiF1 channel) therefore reveals the intrinsic FUV spectrum of eta Carinae without this stellar contamination. The HIRS spectrum contains strong interstellar H2 having high rotational excitation (up to J=8). Most of the atomic species with prominent ISM features (C II, Fe II, Ar I, P II, etc) also have strong blue-shifted absorption to v= ~ -580 km/s that is associated with expanding debris from the 1840 eruption.

  19. Delay in post-ovariectomy estrogen replacement negates estrogen-induced augmentation of post-exercise muscle satellite cell proliferation.

    Science.gov (United States)

    Mangan, Gary; Iqbal, Sobia; Hubbard, Andrew; Hamilton, Victoria; Bombardier, Eric; Tiidus, Peter M

    2015-11-01

    This study examined the effects of a delay in post-ovariectomy replacement of 17β-estradiol (estrogen) on the post-exercise proliferation of muscle satellite cells. Nine-week-old, ovariectomized, female Sprague-Dawley rats (n = 64) were distributed among 8 groups based on estrogen status (0.25 mg estrogen pellet or sham), exercise status (90 min run at 17 m·min(-1) and a grade of -13.5° or unexercised), and estrogen replacement ("proximal", estrogen replacement within 2 weeks; or "delayed", estrogen replacement at 11 weeks following ovariectomy). Significant increases in satellite cells were found in the soleus and white gastrocnemius muscle (immunofluorescent colocalization of nuclei with Pax7) 72 h following eccentric exercise (p exercised groups. Proximal E2 replacement resulted in a further augmentation of muscle satellite cells in exercised rats (p estrogen replacement group. Expression of PI3K was unaltered and phosphorylation of Akt relative to total Akt increased following estrogen supplementation and exercise. Exercise alone did not alter the expression levels of Akt. An 11 week delay in post-ovariectomy estrogen replacement negated the augmenting influence seen with proximal (2 week delay) post-ovariectomy estrogen replacement on post-exercise muscle satellite cell proliferation. This effect appears to be independent of the PI3K-Akt signaling pathway.

  20. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    Directory of Open Access Journals (Sweden)

    Matthew Emerson Randolph

    2015-10-01

    Full Text Available The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies, such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in the pathology of some muscular dystrophies. The biology of muscle stem cells varies depending on their embryologic origins and the muscles with which they are associated. Here we review the biology of skeletal muscle stem cell populations of eight different muscle groups. Understanding the biological variation of skeletal muscles and their resident stem cells could provide valuable insight into mechanisms underlying the susceptibility of certain muscles to myopathic disease.

  1. Planning the FUSE Mission Using the SOVA Algorithm

    Science.gov (United States)

    Lanzi, James; Heatwole, Scott; Ward, Philip R.; Civeit, Thomas; Calvani, Humberto; Kruk, Jeffrey W.; Suchkov, Anatoly

    2011-01-01

    Three documents discuss the Sustainable Objective Valuation and Attainability (SOVA) algorithm and software as used to plan tasks (principally, scientific observations and associated maneuvers) for the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. SOVA is a means of managing risk in a complex system, based on a concept of computing the expected return value of a candidate ordered set of tasks as a product of pre-assigned task values and assessments of attainability made against qualitatively defined strategic objectives. For the FUSE mission, SOVA autonomously assembles a week-long schedule of target observations and associated maneuvers so as to maximize the expected scientific return value while keeping the satellite stable, managing the angular momentum of spacecraft attitude- control reaction wheels, and striving for other strategic objectives. A six-degree-of-freedom model of the spacecraft is used in simulating the tasks, and the attainability of a task is calculated at each step by use of strategic objectives as defined by use of fuzzy inference systems. SOVA utilizes a variant of a graph-search algorithm known as the A* search algorithm to assemble the tasks into a week-long target schedule, using the expected scientific return value to guide the search.

  2. A muscle stem cell for every muscle: variability of satellite cell biology among different muscle groups

    OpenAIRE

    Matthew Emerson Randolph; Pavlath, Grace K.

    2015-01-01

    The human body contains approximately 640 individual skeletal muscles. Despite the fact that all of these muscles are composed of striated muscle tissue, the biology of these muscles and their associated muscle stem cell populations are quite diverse. Skeletal muscles are affected differentially by various muscular dystrophies, such that certain genetic mutations specifically alter muscle function in only a subset of muscles. Additionally, defective muscle stem cells have been implicated in t...

  3. Effect of MSTN Propeptide and shRNA Co-expression Vector on Proliferation of Skeletal Muscle Satellite Cells

    Institute of Scientific and Technical Information of China (English)

    Feng Lin-he; Wang Xin; Lu Ming; Tong Hui-li; Li Shu-feng; Yan Yun-qin

    2014-01-01

    Myostatin (MSTN) is a negative regulator of skeletal muscle growth, in order to study the effect of inhibition MSTN expression on the proliferation of bovine skeletal muscle satellite cells, we constructed co-expression vector pcDNA3.1-Pro-MSTNshRNA, transfected it into muscle satellite cells by Liposome 2000, and detected cell proliferation changes by CCK-8 method and flow cytometry after 48 h. The expressions of P21 and CDK2 were detected by Western blot and real-time PCR. The results showed that the cell vitality of experimental groups significantly increased than that of the negative control, and cells in S phase also increased significantly (P<0.05). After knocked down MSTN gene, P21 expression decreased (P<0.05), but CDK2 gene expression increased (P<0.05). These results indicated that MSTN gene expression was associated with P21 and CDK2, the proliferation of skeletal muscle satellite cells could be promoted while MSTN was inhibited, which provided a theoretical basis for the study on transgenic cattle.

  4. Satellite glial cells can promote the extension of neuronal axons in vitro

    Institute of Scientific and Technical Information of China (English)

    Jiu-Hong Zhao; Yi-Di Huang; Xi-Nan Yi; Quan-Peng Zhang; Xian-Fang Zhang; Xu Dong; Gang Luo; Hai-Ying Zhang; Kun-Ju Wang; Mei-Li Lao

    2015-01-01

    Objective: To study the influence of satellite glial cells (SGCs) on the outgrowth of neuronal neurite and the role of Slit1 protein and the contact with neurons in this process, in vitro. Methods: Neurons culture and SGC-neuron co-culture were used as the cell models. The length of axons and dendrites were measured via immunofluorescence to observe the influence of SGCs on the outgrowth of neuronal neurite. The Slit1 protein was added into SGC-neuron co-culture model. The length of dendrites was measured via immunofluorescence at different point times. Result: The anatomical relationship between neurons and SGCs changed as culture period expand. At 12 h after culture, SGCs all surrounded neurons; by 72 h after culture, SGCs were all off neurons. SGCs can promote the growth of neuronal axos, but inhibit the growth of its dendrites; when SGCs closely contact with neurons, the effect of Slit1 on promoting the dendritic growth is not obvious, but when SGCs were off neurons, the effect of Slit1 on promoting the dendritic growth is significant. Conclusion: SGCs can promote the growth of neuronal axos, but inhibit the growth of its dendrites; Slit- Robo signaling pathways and contact with neurons play a role in this process.

  5. The differential proliferative ability of satellite cells in Lantang and Landrace pigs.

    Directory of Open Access Journals (Sweden)

    Xiu-qi Wang

    Full Text Available Here, for the first time, we evaluate the hypothesis that the proliferative abilities of satellite cells (SCs isolated from Lantang (indigenous Chinese pigs and Landrace pigs, which differ in muscle characteristics, are different. SCs were isolated from the longissimus dorsi muscle of neonatal Lantang and Landrace pigs. Proliferative ability was estimated by the count and proliferative activity of viable cells using a hemocytometer and MTT assay at different time points after seeding, respectively. Cell cycle information was detected by flow cytometry. Results showed that there was a greater (P<0.05 number of SCs in Lantang pigs compared with Landrace pigs after 72 h of culture. The percentage of cell population in S phase and G(2/M phases in Lantang pigs were higher (P<0.05, while in G(0/G(1 phase was lower (P<0.05 in comparison with the Landrace pigs. The mRNA abundances of MyoD, Myf5, myogenin and Pax7 in SCs from Lantang pigs were higher (P<0.05, while those of myostatin, Smad3 and genes in the mammalian target of rapamycin (mTOR pathway (with the exception of 4EBP1 were lower (P<0.05 than the Landrace pigs. Protein levels of MyoD, myogenin, myostatin, S6K, phosphorylated mTOR and phosphorylated eIF4E were consistent with the corresponding mRNA abundance. Collectively, these findings suggested that SCs in the two breeds present different proliferative abilities, and the proliferative potential of SCs in Lantang pigs is higher than in Landrace pigs.

  6. Dnmt3a Regulates Proliferation of Muscle Satellite Cells via p57Kip2

    Science.gov (United States)

    Naito, Masashi; Mori, Masaki; Inagawa, Masayo; Miyata, Kohei; Hashimoto, Naohiro; Tanaka, Sakae; Asahara, Hiroshi

    2016-01-01

    Cell differentiation status is defined by the gene expression profile, which is coordinately controlled by epigenetic mechanisms. Cell type-specific DNA methylation patterns are established by chromatin modifiers including de novo DNA methyltransferases, such as Dnmt3a and Dnmt3b. Since the discovery of the myogenic master gene MyoD, myogenic differentiation has been utilized as a model system to study tissue differentiation. Although knowledge about myogenic gene networks is accumulating, there is only a limited understanding of how DNA methylation controls the myogenic gene program. With an aim to elucidate the role of DNA methylation in muscle development and regeneration, we investigate the consequences of mutating Dnmt3a in muscle precursor cells in mice. Pax3 promoter-driven Dnmt3a-conditional knockout (cKO) mice exhibit decreased organ mass in the skeletal muscles, and attenuated regeneration after cardiotoxin-induced muscle injury. In addition, Dnmt3a-null satellite cells (SCs) exhibit a striking loss of proliferation in culture. Transcriptome analysis reveals dysregulated expression of p57Kip2, a member of the Cip/Kip family of cyclin-dependent kinase inhibitors (CDKIs), in the Dnmt3a-KO SCs. Moreover, RNAi-mediated depletion of p57Kip2 replenishes the proliferation activity of the SCs, thus establishing a role for the Dnmt3a-p57Kip2 axis in the regulation of SC proliferation. Consistent with these findings, Dnmt3a-cKO muscles exhibit fewer Pax7+ SCs, which show increased expression of p57Kip2 protein. Thus, Dnmt3a is found to maintain muscle homeostasis by epigenetically regulating the proliferation of SCs through p57Kip2. PMID:27415617

  7. Dnmt3a Regulates Proliferation of Muscle Satellite Cells via p57Kip2.

    Directory of Open Access Journals (Sweden)

    Masashi Naito

    2016-07-01

    Full Text Available Cell differentiation status is defined by the gene expression profile, which is coordinately controlled by epigenetic mechanisms. Cell type-specific DNA methylation patterns are established by chromatin modifiers including de novo DNA methyltransferases, such as Dnmt3a and Dnmt3b. Since the discovery of the myogenic master gene MyoD, myogenic differentiation has been utilized as a model system to study tissue differentiation. Although knowledge about myogenic gene networks is accumulating, there is only a limited understanding of how DNA methylation controls the myogenic gene program. With an aim to elucidate the role of DNA methylation in muscle development and regeneration, we investigate the consequences of mutating Dnmt3a in muscle precursor cells in mice. Pax3 promoter-driven Dnmt3a-conditional knockout (cKO mice exhibit decreased organ mass in the skeletal muscles, and attenuated regeneration after cardiotoxin-induced muscle injury. In addition, Dnmt3a-null satellite cells (SCs exhibit a striking loss of proliferation in culture. Transcriptome analysis reveals dysregulated expression of p57Kip2, a member of the Cip/Kip family of cyclin-dependent kinase inhibitors (CDKIs, in the Dnmt3a-KO SCs. Moreover, RNAi-mediated depletion of p57Kip2 replenishes the proliferation activity of the SCs, thus establishing a role for the Dnmt3a-p57Kip2 axis in the regulation of SC proliferation. Consistent with these findings, Dnmt3a-cKO muscles exhibit fewer Pax7+ SCs, which show increased expression of p57Kip2 protein. Thus, Dnmt3a is found to maintain muscle homeostasis by epigenetically regulating the proliferation of SCs through p57Kip2.

  8. The effect of nutritional status and muscle fiber type on myogenic satellite cell fate and apoptosis.

    Science.gov (United States)

    Powell, D J; McFarland, D C; Cowieson, A J; Muir, W I; Velleman, S G

    2014-01-01

    Satellite cells (SC) are multipotential stem cells that can be induced by nutrition to alter their cellular developmental fate, which may vary depending on their fiber type origin. The objective of the current study was to determine the effect of restricting protein synthesis on inducing adipogenic transdifferentiation and apoptosis of SC originating from fibers of the fast glycolytic pectoralis major (p. major) and fast oxidative and glycolytic biceps femoris (b. femoris) muscles of the chicken. The availability of the essential sulfur amino acids Met and Cys was restricted to regulate protein synthesis during SC proliferation and differentiation. The SC were cultured and treated with 1 of 6 Met/Cys concentrations: 60/192, 30/96 (control), 7.5/24, 3/9.6, 1/3.2, or 0/0 mg/L. Reductions in Met/Cys concentrations from the control level resulted in increased lipid staining and expression of the adipogenic marker genes peroxisome proliferator-activated receptor gamma and stearoyl-CoA desaturase during differentiation in the p. major SC. Although b. femoris SC had increased lipid staining at lower Met/Cys concentrations, there was no increase in expression of either adipogenic gene. For both muscle types, SC Met/Cys, concentration above the control increased the expression of peroxisome proliferator-activated receptor gamma and stearoyl-CoA desaturase during differentiation. As Met/Cys concentration was decreased during proliferation, a dose-dependent decline in all apoptotic cells occurred except for early apoptotic cells in the p. major, which had no treatment effect (P nutrition on SC transdifferentiation to an adipogenic lineage and apoptosis, and the effect of fiber type on this response in an in vitro context.

  9. Fused combiners for photonic crystal bers

    DEFF Research Database (Denmark)

    Noordegraaf, Danny

    The work presented in this Ph.D. thesis focuses on the fabrication of fused combiners for high-power fiber lasers and amplifiers. The main focus of the Ph.D. project was to further develop the fused pump combiners for airclad photonic crystal bers (PCFs), and implement a signal feed...

  10. Tuning the LUMO level of organic photovoltaic solar cells by conjugately fusing graphene flake: A DFT-B3LYP study

    Science.gov (United States)

    Ganji, M. Darvish; Tajbakhsh, M.; Kariminasab, M.; Alinezhad, H.

    2016-07-01

    The efficiency of polymer solar cells can be essentially enhanced by improving the performance of electron acceptor materials especially by increasing its lowest unoccupied molecular orbital (LUMO) level. To this aim, the electronic properties of an extremely π-extended system, graphene flake and functionalized graphene flake with phenyl-C-butyric methyl ester (PCBM) group, were investigated and compared with those of C60 ones. Several properties of phenyl-C61-butyric methyl ester ([C60]PCBM) derivatives have been calculated and compared against the experimental and other theoretical results. All geometrical and electronic structures calculations were carried out by using the density functional theory (DFT) method at the B3LYP level of theory. The results show that the phenyl ring of [C60]PCBM was substituted with the methoxy groups to increase the LUMO level of the respective system which is in agreement with other studies. We found that graphene flake functionalized by methoxy-PCBM group offer significant increase in the value of the LUMO energy level in comparison with C60 counterpart. Furthermore, the electrophilicity of this compound is lower than that of the other counterparts, which results in higher open circuit voltage (Voc) value in the photovoltaic device. These findings could provide fundamental insights in improving the Voc value as well as raising the LUMO levels of electron acceptor materials and may also serve as an alternative strategy to increase open circuit voltage in polymer solar cells.

  11. Antibodies against ribosomal protein S29 (RPS29) fused with glutathione's transferase specially react with native RPS29 in mouse and human cells

    Institute of Scientific and Technical Information of China (English)

    Liu Jia; Zhang Junlei; Han Junfeng; Li Dongying; Jian Rui; Rao XianCai; Chen Wei; Wang Jiali; Xu Xiaofeng; Hu Zhen

    2011-01-01

    The ribosomal protein S29 also known as RPS29,is not only a component of the 40S subunit of ribosome,but also involved in embryonic development,oncogenesis and other pathologic conditions. However,rare commercial antibody against RPS29 restricts the discovery of precise physiological and pathological function of this protein. In this study,the whole RPS29 gene was inserted into plasmid pGEX-6p-1 to express glutathione's transferase (GST) fusion proteins in Escherichia coli (E. coli) strain BL21. High yields of soluble recombinant proteins were obtained. Mice were immunized with the recombinant RPS29 protein. The serum from the immunized mice could specially react with purified recombinant RPS29 proteins and native RPS29 proteins in CCE cells by western blotting,immunofluorescence staining and flow cytometric analysis. Further more the polyclonal antibodies also reacted specifically with human cell strain ECV304,which showed typical cytoplasmatic fluorescence. The polyclonal antibodies we prepared would be an available tool for studying the roles of RPS29 in embryonic development and human diseases.

  12. Production of N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) fused with secretory signal Igκ in insect cells.

    Science.gov (United States)

    Horynová, Milada; Takahashi, Kazuo; Hall, Stacy; Renfrow, Matthew B; Novak, Jan; Raška, Milan

    2012-02-01

    The human UDP-N-acetyl-α-d-galactosamine:polypeptide N-acetylgalactosaminyl-transferase 2 (GalNAc-T2) is one of the key enzymes that initiate synthesis of hinge-region O-linked glycans of human immunoglobulin A1 (IgA1). We designed secreted soluble form of human GalNAc-T2 as a fusion protein containing mouse immunoglobulin light chain kappa secretory signal and expressed it using baculovirus and mammalian expression vectors. The recombinant protein was secreted by insect cells Sf9 and human HEK 293T cells in the culture medium. The protein was purified from the media using affinity Ni-NTA chromatography followed by stabilization of purified protein in 50mM Tris-HCl buffer at pH 7.4. Although the purity of recombinant GalNAc-T2 was comparable in both expression systems, the yield was higher in Sf9 insect expression system (2.5mg of GalNAc-T2 protein per 1L culture medium). The purified soluble recombinant GalNAc-T2 had an estimated molecular mass of 65.8kDa and its amino-acid sequence was confirmed by mass-spectrometric analysis. The enzymatic activity of Sf9-produced recombinant GalNAc-T2 was determined by the quantification of enzyme-mediated attachment of GalNAc to synthetic IgA1 hinge-region peptide as the acceptor and UDP-GalNAc as the donor. In conclusion, murine immunoglobulin kappa secretory signal was used for production of secreted enzymatically active GalNAc-T2 in insect baculovirus expression system.

  13. Aged Muscle Demonstrates Fiber-Type Adaptations in Response to Mechanical Overload, in the Absence of Myofiber Hypertrophy, Independent of Satellite Cell Abundance.

    Science.gov (United States)

    Lee, Jonah D; Fry, Christopher S; Mula, Jyothi; Kirby, Tyler J; Jackson, Janna R; Liu, Fujun; Yang, Lin; Dupont-Versteegden, Esther E; McCarthy, John J; Peterson, Charlotte A

    2016-04-01

    Although sarcopenia, age-associated loss of muscle mass and strength, is neither accelerated nor exacerbated by depletion of muscle stem cells, satellite cells, we hypothesized that adaptation in sarcopenic muscle would be compromised. To test this hypothesis, we depleted satellite cells with tamoxifen treatment of Pax7(CreER)-DTA mice at 4 months of age, and 20 months later subjected the plantaris muscle to 2 weeks of mechanical overload. We found myofiber hypertrophy was impaired in aged mice regardless of satellite cell content. Even in the absence of growth, vehicle-treated mice mounted a regenerative response, not apparent in tamoxifen-treated mice. Further, myonuclear accretion occurred in the absence of growth, which was prevented by satellite cell depletion, demonstrating that myonuclear addition is insufficient to drive myofiber hypertrophy. Satellite cell depletion increased extracellular matrix content of aged muscle that was exacerbated by overload, potentially limiting myofiber growth. These results support the idea that satellite cells regulate the muscle environment, and that their loss during aging may contribute to fibrosis, particularly during periods of remodeling. Overload induced a fiber-type composition improvement, independent of satellite cells, suggesting that aged muscle is very responsive to exercise-induced enhancement in oxidative capacity, even with an impaired hypertrophic response. © The Author 2015. Published by Oxford University Press on behalf of the Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. The activity of satellite cells and myonuclei following 8 weeks of strength training in young men with suppressed testosterone levels

    DEFF Research Database (Denmark)

    Kvorning, T; Kadi, F; Schjerling, P

    2015-01-01

    AIM: To investigate how suppression of endogenous testosterone during an 8-week strength training period influences the activity of satellite cells and myonuclei. METHODS: Twenty-two moderately trained young men participated in this randomized, placebo-controlled, and double-blinded intervention...... from the mid-portion of the vastus lateralis muscle. RESULTS: Testosterone resting level in goserelin was 10-20 times lower compared with placebo, and the training-induced increase in the level of testosterone was abolished in goserelin. Training increased satellite cells number in type II fibres by 20......% in placebo and by 52% in goserelin (P cells and myonuclei were seen in type I fibres in either group. Data from the microarray analysis...

  15. Effects of Chronic Blood-Flow Restriction Exercise on Skeletal Muscle Size and Myogenic Satellite Cell Expression

    DEFF Research Database (Denmark)

    Aagaard, Per; Jacobsen, Mikkel; Jensen, Kasper Yde

    2016-01-01

    of continued sports activity, resulting in visible hypertrophy of his left leg. AIM: To study the effect of chronic blood-flow restricted (BFR) exercise conditions on skeletal muscle size and myogenic satellite cell (SC) expression in an arterio-venous shunt patient. METHODS: Muscle biopsies were obtained from......-regulation in myogenic satellite cell activity within all stages of the cell cycle, which was accompanied by substantial muscle hypertrophy. Specifically, muscle fiber cross-sectional area (40%) and myonuclei number (15%) were elevated in the affected leg, together with an elevated myonuclear domain (20%). This single......-case study confirms previous result from our Lab demonstrating that blood-flow restricted muscle exercise leads to a marked activation of myogenic SCs, upregulated myonuclei number and marked myofiber hypertrophy....

  16. Non-Complexing Anions for Quantitative Speciation Studies Using Raman Spectroscopy in Fused Silica High-Pressure Optical Cells Under Hydrothermal Conditions.

    Science.gov (United States)

    Applegarth, Lucas M S G A; Alcorn, Christopher; Bissonette, Katherine; Noël, John; Tremaine, Peter R

    2015-08-01

    This paper reports methods for obtaining time-dependent reduced isotropic Raman spectra of aqueous species in quartz capillary high-pressure optical cells under hydrothermal conditions, as a means of determining quantitative speciation in hydrothermal fluids. The methods have been used to determine relative Raman scattering coefficients and to examine the thermal decomposition kinetics of the non-complexing anions bisulfate (HSO4(-)), perchlorate (CIO4(-)), perrhenate (ReO4(-)), and trifluoromethanesulfonate, or "triflate" (CF3SO3(-)) in acidic and neutral solutions at temperatures up to 400°C and 30 MPa. Arrhenius expressions for calculating the thermal decomposition rate constants are also reported. Thermal stabilities in the acidic solutions followed the order HSO4(-) (stable) > ReO4(-) > CIO4(-) > CF3SO3(-), with half-lives (t1/2) > 7 h at 300°C. In neutral solutions, the order was HSO4(-) (stable) > CF3SO3(-) > ReO4(-) > CIO4(-), with t1/2 > 8 h at 350°C. CF3SO3(-) was extremely stable in neutral solutions, with t1/2 > 11 h at 400°C.

  17. Laser welding of fused quartz

    Science.gov (United States)

    Piltch, Martin S.; Carpenter, Robert W.; Archer, III, McIlwaine

    2003-06-10

    Refractory materials, such as fused quartz plates and rods are welded using a heat source, such as a high power continuous wave carbon dioxide laser. The radiation is optimized through a process of varying the power, the focus, and the feed rates of the laser such that full penetration welds may be accomplished. The process of optimization varies the characteristic wavelengths of the laser until the radiation is almost completely absorbed by the refractory material, thereby leading to a very rapid heating of the material to the melting point. This optimization naturally occurs when a carbon dioxide laser is used to weld quartz. As such this method of quartz welding creates a minimum sized heat-affected zone. Furthermore, the welding apparatus and process requires a ventilation system to carry away the silicon oxides that are produced during the welding process to avoid the deposition of the silicon oxides on the surface of the quartz plates or the contamination of the welds with the silicon oxides.

  18. Age-specific functional epigenetic changes in p21 and p16 in injury-activated satellite cells.

    Science.gov (United States)

    Li, Ju; Han, Suhyoun; Cousin, Wendy; Conboy, Irina M

    2015-03-01

    The regenerative capacity of muscle dramatically decreases with age because old muscle stem cells fail to proliferate in response to tissue damage. Here, we uncover key age-specific differences underlying this proliferative decline: namely, the genetic loci of cyclin/cyclin-dependent kinase (CDK) inhibitors (CDKIs) p21 and p16 are more epigenetically silenced in young muscle stem cells, as compared to old, both in quiescent cells and those responding to tissue injury. Interestingly, phosphorylated ERK (pERK) induced in these cells by ectopic FGF2 is found in association with p21 and p16 promoters, and moreover, only in the old cells. Importantly, in the old satellite cells, FGF2/pERK silences p21 epigenetically and transcriptionally, which leads to reduced p21 protein levels and enhanced cell proliferation. In agreement with the epigenetic silencing of the loci, young muscle stem cells do not depend as much as old on ectopic FGF/pERK for their myogenic proliferation. In addition, other CDKIs, such asp15(INK4B) and p27(KIP1) , become elevated in satellite cells with age, confirming and explaining the profound regenerative defect of old muscle. This work enhances our understanding of tissue aging, promoting strategies for combating age-imposed tissue degeneration.

  19. IGF-1,bFGF EXPRESSION AND VASCULAR REGENERATION IN ACUTE INFARCTED CANINE MYOCARDIUM AFTER AUTOLOGUS SKELETAL MUSCLE SATELLITE CELL IMPLANTATION

    Institute of Scientific and Technical Information of China (English)

    朱洪生; 钟竑; 张臻

    2003-01-01

    Objective To study the cell growth factor secretion and vascular regeneration in acute infarcted myocardium after autologous skeletal muscle satellite cell implantation.MethodsAutologous skeletal muscle satellite cells from adult mongrel canine were implanted into the acute myocardial infarct site via the ligated left anterior descending (LAD) artery. Specimens were harvested at 2, 4, 8 weeks after implantation for the expression of insulin like growth factor-1 (IGF-1), basic fibroblast growth factor (Bfgf) and the vascular density.ResultsThe expression of IGF-1, Bfgf and the vascular density in skeletal muscle satellite cell implant group were higher than that in the control group.ConclusionThe skeletal muscle satellite cells, after being implanted into the acute myocardial infarction, not only showed myocardial regeneration, but also showed the ability to secrete the cell factors, hence representing a positive effect on the regeneration of the infarcted myocardium.

  20. Fiber Type-Specific Satellite Cell Content in Cyclists Following Heavy Training with Carbohydrate and Carbohydrate-Protein Supplementation

    Science.gov (United States)

    McKenzie, Alec I.; D'Lugos, Andrew C.; Saunders, Michael J.; Gworek, Keith D.; Luden, Nicholas D.

    2016-01-01

    The central purpose of this study was to evaluate the fiber type-specific satellite cell and myonuclear responses of endurance-trained cyclists to a block of intensified training, when supplementing with carbohydrate (CHO) vs. carbohydrate-protein (PRO). In a crossover design, endurance-trained cyclists (n = 8) performed two consecutive training periods, once supplementing with CHO (de facto “control” condition) and the other with PRO. Each training period consisted of 10 days of intensified cycle training (ICT–120% increase in average training duration) followed by 10 days of recovery (RVT–reduced volume training; 33% volume reduction vs. normal training). Skeletal muscle biopsies were obtained from the vastus lateralis before and after ICT and again following RVT. Immunofluorescent microscopy was used to quantify SCs (Pax7+), myonuclei (DAPI+), and myosin heavy chain I (MyHC I). Data are expressed as percent change ± 90% confidence limits. The 10-day block of ICTCHO increased MyHC I SC content (35 ± 28%) and myonuclear density (16 ± 6%), which remained elevated following RVTCHO (SC = 69 ± 50% vs. PRE; Nuclei = 17 ± 15% vs. PRE). MyHC II SC and myonuclei were not different following ICTCHO, but were higher following RVTCHO (SC = +33 ± 31% vs. PRE; Nuclei = 15 ± 14% vs. PRE), indicating a delayed response compared to MyHC I fibers. The MyHC I SC pool increased following ICTPRO (37 ± 37%), but without a concomitant increase in myonuclei. There were no changes in MyHC II SC or myonuclei following ICTPRO. Collectively, these trained endurance cyclists possessed a relatively large pool of SCs that facilitated rapid (MyHC I) and delayed (MyHC II) satellite cell proliferation and myonuclear accretion under carbohydrate conditions. The current findings strengthen the growing body of evidence demonstrating alterations in satellite cell number in the absence of hypertrophy. Satellite cell pool expansion is typically viewed as an advantageous response to

  1. Effect of eccentric contraction on satellite cell activation in human vastus lateralis muscle.

    Science.gov (United States)

    Imaoka, Yoko; Kawai, Minako; Mori, Futoshi; Miyata, Hirofumi

    2015-09-01

    We compared the time-course of satellite cell (SC) activation between eccentric and concentric contractions in the vastus lateralis (VL) muscle after step exercise. Young adults participated in a 30-min step up/down exercise which mainly involved concentric contractions with the right VL muscle and eccentric contractions with the left VL muscle. The concentric and eccentric contraction phases of the VL muscles were identified by changes in the electromyogram (EMG) and knee joint angle. Biopsy samples were taken from both VL muscles at three time periods: before the exercise and 2 and 5 days after the exercise. We found that the numbers of SCs were significantly increased in the type IIa fibers of the left VL at 2 and 5 days after the exercise. The expression of both hepatocyte growth factor (HGF) and myogenic differentiation 1 (MyoD) mRNA had significantly increased in the left VL at 2 and 5 days after the exercise and in the right VL at 5 days after the exercise. The expression of transient receptor potential canonical (TRPC) 1 mRNA also increased in the left VL at 2 days after exercise. These results indicate that eccentric contraction can effectively activate SC proliferation for up to 5 days after exercise. Similar changes in HGF, MyoD and TRPC1 mRNA expression suggest that HGF/c-Met signal activation through cation influx has a major impact on skeletal muscle SC activation in response to eccentric exercise.

  2. Smad3 signaling is required for satellite cell function and myogenic differentiation of myoblasts

    Institute of Scientific and Technical Information of China (English)

    Xiaojia Ge; Ravi Kambadur; Craig McFarlane; Anuradha Vajjala; Sudarsanareddy Lokireddy; Zhi Hui Ng; Chek Kun Tan; Nguan Soon Tan; Walter Wahli; Mridula Sharma

    2011-01-01

    TGF-β and myostatin are the two most important regulators of muscle growth.Both growth factors have been shown to signal through a Smad3-dependent pathway.However to date,the role of Smad3 in muscle growth and differentiation is not investigated.Here,we demonstrate that Smad3-null mice have decreased muscle mass and pronounced skeletal muscle atrophy.Consistent with this,we also find increased protein ubiquitination and elevated levels of the ubiquitin E3 ligase MuRF1 in muscle tissue isolated from Smad3-null mice.Loss of Smad3 also led to defective satellite cell (SC) functionality.Smad3-null SCs showed reduced propensity for self-renewal,which may lead to a progressive loss of SC number.Indeed,decreased SC number was observed in skeletal muscle from Smad3- null mice showing signs of severe muscle wasting.Further in vitro analysis of primary myoblast cultures identified that Smad3-nuil myoblasts exhibit impaired proliferation,differentiation and fusion,resulting in the formation of atrophied myotubes.A search for the molecular mechanism revealed that loss of Smad3 results in increased myostatin expression in Smad3-null muscle and myoblasts.Given that myostatin is a negative regulator,we hypothesize that increased myostatin levels are responsible for the atrophic phenotype in Smad3-null mice.Consistent with this theory,inactivation of myostatin in Smad3-null mice rescues the muscle atrophy phenotype.

  3. Whey protein supplementation accelerates satellite cell proliferation during recovery from eccentric exercise.

    Science.gov (United States)

    Farup, Jean; Rahbek, Stine Klejs; Knudsen, Inge Skovgaard; de Paoli, Frank; Mackey, Abigail L; Vissing, Kristian

    2014-11-01

    Human skeletal muscle satellite cells (SCs) are essential for muscle regeneration and remodeling processes in healthy and clinical conditions involving muscle breakdown. However, the potential influence of protein supplementation on post-exercise SC regulation in human skeletal muscle has not been well investigated. In a comparative human study, we investigated the effect of hydrolyzed whey protein supplementation following eccentric exercise on fiber type-specific SC accumulation. Twenty-four young healthy subjects received either hydrolyzed whey protein + carbohydrate (whey, n = 12) or iso-caloric carbohydrate (placebo, n = 12) during post-exercise recovery from 150 maximal unilateral eccentric contractions. Prior to and 24, 48 and 168 h post-exercise, muscle biopsies were obtained from the exercise leg and analyzed for fiber type-specific SC content. Maximal voluntary contraction (MVC) and serum creatine kinase (CK) were evaluated as indices of recovery from muscle damage. In type II fiber-associated SCs, the whey group increased SCs/fiber from 0.05 [0.02; 0.07] to 0.09 [0.06; 0.12] (p eccentric exercise.

  4. A satellite cell-specific knockout of the androgen receptor reveals myostatin as a direct androgen target in skeletal muscle.

    Science.gov (United States)

    Dubois, Vanessa; Laurent, Michaël R; Sinnesael, Mieke; Cielen, Nele; Helsen, Christine; Clinckemalie, Liesbeth; Spans, Lien; Gayan-Ramirez, Ghislaine; Deldicque, Louise; Hespel, Peter; Carmeliet, Geert; Vanderschueren, Dirk; Claessens, Frank

    2014-07-01

    Androgens have well-established anabolic actions on skeletal muscle, although the direct effects of the androgen receptor (AR) in muscle remain unclear. We generated satellite cell-specific AR-knockout (satARKO) mice in which the AR is selectively ablated in satellite cells, the muscle precursor cells. Total-limb maximal grip strength is decreased by 7% in satARKO mice, with soleus muscles containing ∼10% more type I fibers and 10% less type IIa fibers than the corresponding control littermates. The weight of the perineal levator ani muscle is markedly reduced (-52%). Thus, muscle AR is involved in fiber-type distribution and force production of the limb muscles, while it is a major determinant of the perineal muscle mass. Surprisingly, myostatin (Mstn), a strong inhibitor of skeletal muscle growth, is one of the most androgen-responsive genes (6-fold reduction in satARKO) through direct transcription activation by the AR. Consequently, muscle hypertrophy in response to androgens is augmented in Mstn-knockout mice. Our finding that androgens induce Mstn signaling to restrain their own anabolic actions has implications for the treatment of muscle wasting disorders.-Dubois, V., Laurent, M. R., Sinnesael, M., Cielen, N., Helsen, C., Clinckemalie, L., Spans, L., Gayan-Ramirez, G., Deldicque, L., Hespel, P., Carmeliet, G., Vanderschueren, D., and Claessens, F. A satellite cell-specific knockout of the androgen receptor reveals myostatin as a direct androgen target in skeletal muscle.

  5. Dynamic simulation of flywheel-type fuses

    Directory of Open Access Journals (Sweden)

    Editorial Office

    1996-07-01

    Full Text Available Rounds of ammunition are normally armed with a fuse. In this study, a fuse is developed which uses a flywheel-type mechanism controlled by time or distance. Due to its simplicity of operation and construction, the concept is expected to have high reliabil­ity. The dynamic response of all the components of this flywheel-type fuse is mathematically modelled. Simulation software was developed which connects the mathematical models of the various components. With the definition of boundary values, the response of the projectile, flywheel and other components can be determined continuously for firing and in-flight conditions.

  6. Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth.

    Science.gov (United States)

    Farup, Jean; Rahbek, Stine Klejs; Riis, Simon; Vendelbo, Mikkel Holm; Paoli, Frank de; Vissing, Kristian

    2014-10-15

    Skeletal muscle satellite cells (SCs) are involved in remodeling and hypertrophy processes of skeletal muscle. However, little knowledge exists on extrinsic factors that influence the content of SCs in skeletal muscle. In a comparative human study, we investigated the muscle fiber type-specific association between emergence of satellite cells (SCs), muscle growth, and remodeling in response to 12 wk unilateral resistance training performed as eccentric (Ecc) or concentric (Conc) resistance training ± whey protein (Whey, 19.5 g protein + 19.5 g glucose) or placebo (Placebo, 39 g glucose) supplementation. Muscle biopsies (vastus lateralis) were analyzed for fiber type-specific SCs, myonuclei, and fiber cross-sectional area (CSA). Following training, SCs increased with Conc in both type I and type II fibers (P hypertrophy correlated with whole muscle hypertrophy exclusively following Conc training (P eccentric resistance training while type II fiber hypertrophy was accentuated when combining concentric resistance training with whey protein supplementation.

  7. Creatine supplementation augments the increase in satellite cell and myonuclei number in human skeletal muscle induced by strength training

    DEFF Research Database (Denmark)

    Olsen, Steen; Aagaard, Per; Kadi, Fawzi

    2006-01-01

    ). Furthermore, timed protein/placebo intake were administered at all training sessions. Muscle biopsies were obtained at week 0, 4, 8 (week 8 not CON) and 16 of resistance training (3 days per week). Satellite cells were identified by immunohistochemistry. Muscle mean fibre (MFA) area was determined after...... histochemical analysis. All training regimes were found to increase the proportion of satellite cells, but significantly greater enhancements were observed with creatine supplementation at week 4 (compared to STR-CON) and at week 8 (compared to STR-PRO and STR-CON) (P... number was no longer elevated in STR-CRE, while it remained elevated in STR-PRO and STR-CON. Furthermore, creatine supplementation resulted in an increased number of myonuclei per fibre and increases of 14-17% in MFA at week 4, 8 and 16 (Pincrease in MFA only...

  8. Influence of exercise contraction mode and protein supplementation on human skeletal muscle satellite cell content and muscle fiber growth

    DEFF Research Database (Denmark)

    Farup, Jean; Rahbek, Stine Klejs; Riis, Simon

    2014-01-01

    -specific association between emergence of satellite cells (SCs), muscle growth, and remodeling in response to 12 wk unilateral resistance training performed as eccentric (Ecc) or concentric (Conc) resistance training ± whey protein (Whey, 19.5 g protein + 19.5 g glucose) or placebo (Placebo, 39 g glucose......Skeletal muscle satellite cells (SCs) are involved in remodeling and hypertrophy processes of skeletal muscle. However, little knowledge exists on extrinsic factors that influence the content of SCs in skeletal muscle. In a comparative human study, we investigated the muscle fiber type......) supplementation. Muscle biopsies (vastus lateralis) were analyzed for fiber type-specific SCs, myonuclei, and fiber cross-sectional area (CSA). Following training, SCs increased with Conc in both type I and type II fibers (P

  9. Charge efficiency of Ni/H2 cells during transfer orbit of Telstar 4 satellites

    Science.gov (United States)

    Fang, W. C.; Maurer, Dean W.; Vyas, B.; Thomas, M. N.

    1994-02-01

    The TELSTAR 4 communication satellites being manufactured by Martin Marietta Astro Space (Astro Space) for AT&T are three axis stabilized spacecraft scheduled to be launched on expendable vehicles such as the Atlas or Ariane rockets. Typically, these spacecraft consist of a box that holds the electronics and supports the antenna reflectors and the solar array wings. The wings and reflectors are folded against the sides of the box during launch and the spacecraft is spun for attitude control in that phase; they are then deployed after achieving the final orbit. The launch phase and transfer orbits required to achieve the final geosynchronous orbit typically take 4 to 5 days during which time the power required for command, telemetry, attitude control, heaters, etc., is provided by two 50 AH nickel hydrogen batteries augmented by the exposed outboard solar panels. In the past, this situation has presented no problem since there was a considerable excess of power available from the array. In the case of large high powered spacecraft such as TELSTAR 4, however, the design power levels in transfer orbit approach the time-averaged power available from the exposed surface area of the solar arrays, resulting in a very tight power margin. To compound the difficulty, the array output of the spinning spacecraft in transfer orbit is shaped like a full wave rectified sine function and provides very low charging rates to the batteries during portions of the rotation. In view of the typically low charging efficiency of alkaline nickel batteries at low rates, it was decided to measure the efficiency during a simulation of the TELSTAR 4 conditions at the expected power levels and temperatures on three nickel hydrogen cells of similar design. The unique feature of nickel hydrogen cells that makes the continuous measurement of efficiency possible is that hydrogen is one of the active materials and thus, cell pressure is a direct measure of the state of charge or available capacity

  10. The molecular responses of skeletal muscle satellite cells to continuous expression of IGF-1: implications for the rescue of induced muscular atrophy in aged rats

    Science.gov (United States)

    Chakravarthy, M. V.; Booth, F. W.; Spangenburg, E. E.

    2001-01-01

    Approximately 50% of humans older than 85 years have physical frailty due to weak skeletal muscles. This indicates a need for determining mechanisms to combat this problem. A critical cellular factor for postnatal muscle growth is a population of myogenic precursor cells called satellite cells. Given the complex process of sarcopenia, it has been postulated that, at some point in this process, a limited satellite cell proliferation potential could become rate-limiting to the regrowth of old muscles. It is conceivable that if satellite cell proliferative capacity can be maintained or enhanced with advanced age, sarcopenia could potentially be delayed or prevented. Therefore, the purposes of this paper are to describe whether IGF-I can prevent muscular atrophy induced by repeated cycles of hindlimb immobilization, increase the in vitro proliferation in satellite cells from these muscles and, if so, the molecular mechanisms by which IGF-I mediates this increased proliferation. Our results provide evidence that IGF-I can enhance aged muscle regrowth possibly through increased satellite cell proliferation. The results also suggest that IGF-I enhances satellite cell proliferation by decreasing the cell cycle inhibitor, p27Kip1, through the PI3'-K/Akt pathway. These data provide molecular evidence for IGF-I's rescue effect upon aging-associated skeletal muscle atrophy.

  11. Coordination chemistry in fused-salt solutions

    Science.gov (United States)

    Gruen, D. M.

    1969-01-01

    Spectrophotometric work on structural determinations with fused-salt solutions is reviewed. Constraints placed on the method, as well as interpretation of the spectra, are discussed with parallels drawn to aqueous spectrophotometric curves of the same materials.

  12. Fuse Protects Parabolic-Dish Solar Collector

    Science.gov (United States)

    Selcuk, M. K.

    1983-01-01

    Sliding barrel and shutter protect against overheating. Downward movement of shutter initiated by melting of fuse wire that suspends it. Shutter lowered or raised under operator's control by depressuring or pressurizing hydraulic cylinder.

  13. Organometallic chemistry: Fused ferrocenes come full circle

    Science.gov (United States)

    Musgrave, Rebecca A.; Manners, Ian

    2016-09-01

    Chemists have long been fascinated by electron delocalization, from both a fundamental and applied perspective. Macrocyclic oligomers containing fused ferrocenes provide a new structural framework -- containing strongly interacting metal centres -- that is capable of supporting substantial charge delocalization.

  14. FOXP3+ T Cells Recruited to Sites of Sterile Skeletal Muscle Injury Regulate the Fate of Satellite Cells and Guide Effective Tissue Regeneration

    OpenAIRE

    Alessandra Castiglioni; Gianfranca Corna; Elena Rigamonti; Veronica Basso; Michela Vezzoli; Antonella Monno; Almada, Albert E; Anna Mondino; Wagers, Amy J.; Angelo A. Manfredi; Patrizia Rovere-Querini

    2015-01-01

    Muscle injury induces a classical inflammatory response in which cells of the innate immune system rapidly invade the tissue. Macrophages are prominently involved in this response and required for proper healing, as they are known to be important for clearing cellular debris and supporting satellite cell differentiation. Here, we sought to assess the role of the adaptive immune system in muscle regeneration after acute damage. We show that T lymphocytes are transiently recruited into the musc...

  15. Mycobacterium ulcerans infections cause progressive muscle atrophy and dysfunction, and mycolactone impairs satellite cell proliferation.

    Science.gov (United States)

    Houngbédji, Germain Mabèrou; Bouchard, Patrice; Frenette, Jérôme

    2011-03-01

    Clinical observations from Buruli ulcer (BU) patients in West Africa suggest that severe Mycobacterium ulcerans infections can cause skeletal muscle contracture and atrophy leading to significant impairment in function. In the present study, male mice C57BL/6 were subcutaneously injected with M. ulcerans in proximity to the right biceps muscle, avoiding direct physical contact between the infectious agent and the skeletal muscle. The histological, morphological, and functional properties of the muscles were assessed at different times after the injection. On day 42 postinjection, the isometric tetanic force and the cross-sectional area of the myofibers were reduced by 31% and 29%, respectively, in the proximate-infected muscles relative to the control muscles. The necrotic areas of the proximate-infected muscles had spread to 7% of the total area by day 42 postinjection. However, the number of central nucleated fibers and myogenic regulatory factors (MyoD and myogenin) remained stable and low. Furthermore, Pax-7 expression did not increase significantly in mycolactone-injected muscles, indicating that the satellite cell proliferation is abrogated by the toxin. In addition, the fibrotic area increased progressively during the infection. Lastly, muscle-specific RING finger protein 1 (MuRF-1) and atrogin-1/muscle atrophy F-box protein (atrogin-1/MAFbx), two muscle-specific E3 ubiquitin ligases, were upregulated in the presence of M. ulcerans. These findings confirmed that skeletal muscle is affected in our model of subcutaneous infection with M. ulcerans and that a better understanding of muscle contractures and weakness is essential to develop a therapy to minimize loss of function and promote the autonomy of BU patients.

  16. Reduced masticatory function is related to lower satellite cell numbers in masseter muscle.

    Science.gov (United States)

    Kuijpers, M A R; Grefte, S; Bronkhorst, E M; Carels, C E L; Kiliaridis, S; Von den Hoff, J W

    2014-06-01

    The physiology of masseter muscles is known to change in response to functional demands, but the effect on the satellite cell (SC) population is not known. In this study, the hypothesis is tested that a decreased functional demand of the masseter muscle causes a reduction of SCs. To this end, twelve 5-week-old male Sprague-Dawley rats were put on a soft diet (SD, n = 6) or a hard diet (HD, n = 6) and sacrificed after 14 days. Paraffin sections of the superficial masseter and the m. digastricus (control muscle) were stained with haematoxylin and eosin for tissue survey and with anti-myosin heavy chain (MHC) for slow and fast fibres. Frozen sections of both muscles were double-stained for collagen type IV and Pax7. Slow MHC fibres were equally distributed in the m. digastricus but only localized in a small area of the m. masseter. No differences between HD or SD for the m. digastricus were found. The m. masseter had more SCs per fibre in HD than in SD (0.093 ± 0.007 and 0.081 ± 0.008, respectively; P = 0.027). The m. masseter had more fibres per surface area than the m. digastricus in rats with an SD group (758.1 ± 101.6 and 568.4 ± 85.6, P = 0.047) and a HD group (737.7 ± 32.6 and 592.2 ± 82.2; P = 0.007). The m. digastricus had more SCs per fibre than the m. masseter in the SD group (0.094 ± 0.01 and 0.081 ± 0.008; P = 0.039). These results suggest that reduced masseter muscle function is related to a lower number of SCs. Reduced muscle function might decrease microdamage and hence the requirement of SCs in the muscle fibres.

  17. Akirin2 regulates proliferation and differentiation of porcine skeletal muscle satellite cells via ERK1/2 and NFATc1 signaling pathways

    Science.gov (United States)

    Chen, Xiaoling; Luo, Yanliu; Huang, Zhiqing; Jia, Gang; Liu, Guangmang; Zhao, Hua

    2017-01-01

    Akirin2, a novel nuclear factor, plays an important role in myogenesis. To investigate the role of Akirin2 in proliferation and differentiation of porcine skeletal muscle satellite cells, Akirin2 overexpression and Akirin2 silence technologies were employed. Our results showed that overexpression of Akirin2 markedly enhanced the proliferation and differentiation of porcine skeletal muscle satellite cells, whereas silencing of Akirin2 got the opposite results. Furthermore, our results showed that Akirin2 affected proliferation and differentiation of porcine skeletal muscle satellite cells through extracellular-signal regulated kinase-1/2 (ERK1/2) and NFATc1 signaling pathways. These results indicate that Akirin2 can effectively promote skeletal muscle satellite cells proliferation and differentiation, acting through ERK1/2- and NFATc1-dependent mechanisms. PMID:28327665

  18. Enobosarm (GTx-024) Modulates Adult Skeletal Muscle Mass Independently of the Androgen Receptor in the Satellite Cell Lineage.

    Science.gov (United States)

    Dubois, Vanessa; Simitsidellis, Ioannis; Laurent, Michaël R; Jardi, Ferran; Saunders, Philippa T K; Vanderschueren, Dirk; Claessens, Frank

    2015-12-01

    Androgens increase skeletal muscle mass, but their clinical use is hampered by a lack of tissue selectivity and subsequent side effects. Selective androgen receptor modulators elicit muscle-anabolic effects while only sparingly affecting reproductive tissues. The selective androgen receptor modulator, GTx-024 (enobosarm), is being investigated for cancer cachexia, sarcopenia, and muscle wasting diseases. Here we investigate the role of muscle androgen receptor (AR) in the anabolic effect of GTx-024. In mice lacking AR in the satellite cell lineage (satARKO), the weight of the androgen-sensitive levator ani muscle was lower but was decreased further upon orchidectomy. GTx-024 was as effective as DHT in restoring levator ani weights to sham levels. Expression of the muscle-specific, androgen-responsive genes S-adenosylmethionine decarboxylase and myostatin was decreased by orchidectomy and restored by GTx-024 and DHT in control mice, whereas the expression was low and unaffected by androgen status in satARKO. In contrast, insulin-like growth factor 1Ea expression was not different between satARKO and control muscle, decreased upon castration, and was restored by DHT and GTx-024 in both genotypes. These data indicate that GTx-024 does not selectively modulate AR in the satellite cell lineage and that cells outside this lineage remain androgen responsive in satARKO muscle. Indeed, residual AR-positive cells were present in satARKO muscle, coexpressing the fibroblast-lineage marker vimentin. AR positive, muscle-resident fibroblasts could therefore be involved in the indirect effects of androgens on muscle. In conclusion, both DHT and GTx-024 target AR pathways in the satellite cell lineage, but cells outside this lineage also contribute to the anabolic effects of androgens.

  19. Leucocytes, cytokines and satellite cells: what role do they play in muscle damage and regeneration following eccentric exercise?

    Science.gov (United States)

    Paulsen, Gøran; Mikkelsen, Ulla Ramer; Raastad, Truls; Peake, Jonathan M

    2012-01-01

    Exercise-induced muscle damage is an important topic in exercise physiology. However several aspects of our understanding of how muscles respond to highly stressful exercise remain unclear In the first section of this review we address the evidence that exercise can cause muscle damage and inflammation in otherwise healthy human skeletal muscles. We approach this concept by comparing changes in muscle function (i.e., the force-generating capacity) with the degree of leucocyte accumulation in muscle following exercise. In the second section, we explore the cytokine response to 'muscle-damaging exercise', primarily eccentric exercise. We review the evidence for the notion that the degree of muscle damage is related to the magnitude of the cytokine response. In the third and final section, we look at the satellite cell response to a single bout of eccentric exercise, as well as the role of the cyclooxygenase enzymes (COX1 and 2). In summary, we propose that muscle damage as evaluated by changes in muscle function is related to leucocyte accumulation in the exercised muscles. 'Extreme' exercise protocols, encompassing unaccustomed maximal eccentric exercise across a large range of motion, generally inflict severe muscle damage, inflammation and prolonged recovery (> 1 week). By contrast, exercise resembling regular athletic training (resistance exercise and downhill running) typically causes mild muscle damage (myofibrillar disruptions) and full recovery normally occurs within a few days. Large variation in individual responses to a given exercise should, however be expected. The link between cytokine and satellite cell responses and exercise-induced muscle damage is not so clear The systemic cytokine response may be linked more closely to the metabolic demands of exercise rather than muscle damage. With the exception of IL-6, the sources of systemic cytokines following exercise remain unclear The satellite cell response to severe muscle damage is related to

  20. Satellite Communication.

    Science.gov (United States)

    Technology Teacher, 1985

    1985-01-01

    Presents a discussion of communication satellites: explains the principles of satellite communication, describes examples of how governments and industries are currently applying communication satellites, analyzes issues confronting satellite communication, links mathematics and science to the study of satellite communication, and applies…

  1. 负荷运动对人体骨骼肌卫星细胞的影响%Affect Human Skeletal Muscle Satellite Cells Analysis of the Load Movement

    Institute of Scientific and Technical Information of China (English)

    余群; 王丽平; 翁锡全

    2014-01-01

    骨骼肌在运动损伤、发育和重建等过程中卫星细胞具有重要的生理作用。适宜的运动训练可以激活肌卫星细胞,使之增殖并向成肌的肌卫星细胞转化。文章阐述了骨骼肌卫星细胞的特征、负荷运动对肌卫星细胞的影响,以及运动对卫星细胞的激活与增殖的作用机制;并对人体衰老过程中肌卫星细胞的变化规律进行分析与探讨。%Skeletal muscle satellite cells in skeletal muscle growth and development ,physiology and pathology of skeletal mus‐cle damage repair and remodeling process plays an important role .Appropriate exercise training can activate satellite cells ,satellite cells proliferate and promote myoblast differentiation .In addition ,skeletal muscle satellite cells are generally in a resting state ,it will not participate in the synthesis of gene expression and protein .But it can be activated in sports injuries ,mechanical traction or weight training and other specialized stress during differentiation and fusion into myotubes able to participate in the repair of skele ‐tal muscle .In this paper ,the origins of skeletal muscle satellite cells ,morphological characteristics and different exercise training on human skeletal muscle satellite cells as well as the impact of exercise training on skeletal muscle satellite cell activation ,prolif‐eration and changes of the aging process of skeletal muscle satellite cells were analyzed and discussion .

  2. PPARγ and MyoD are differentially regulated by myostatin in adipose-derived stem cells and muscle satellite cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Feng [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Deng, Bing [Wuhan Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Science and Technology, Wuhan, Hubei, 430208 (China); Wen, Jianghui [Wu Han University of Technology, Wuhan 430074 (China); Chen, Kun [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Liu, Wu; Ye, Shengqiang; Huang, Haijun [Wuhan Institute of Animal Science and Veterinary Medicine, Wuhan Academy of Agricultural Science and Technology, Wuhan, Hubei, 430208 (China); Jiang, Siwen, E-mail: jiangsiwen@mail.hzau.edu.cn [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China); Xiong, Yuanzhu, E-mail: xiongyzhu@163.com [Key Laboratory of Swine Genetics and Breeding of the Agricultural Ministry and Key Laboratory of Agricultural Animal Genetics, Breeding and Reproduction of the Ministry of Education, College of Animal Science and Technology, Huazhong Agricultural University, Wuhan, 430070 (China)

    2015-03-06

    Myostatin (MSTN) is a secreted protein belonging to the transforming growth factor-β (TGF-β) family that is primarily expressed in skeletal muscle and also functions in adipocyte maturation. Studies have shown that MSTN can inhibit adipogenesis in muscle satellite cells (MSCs) but not in adipose-derived stem cells (ADSCs). However, the mechanism by which MSTN differently regulates adipogenesis in these two cell types remains unknown. Peroxisome proliferator-activated receptor-γ (PPARγ) and myogenic differentiation factor (MyoD) are two key transcription factors in fat and muscle cell development that influence adipogenesis. To investigate whether MSTN differentially regulates PPARγ and MyoD, we analyzed PPARγ and MyoD expression by assessing mRNA, protein and methylation levels in ADSCs and MSCs after treatment with 100 ng/mL MSTN for 0, 24, and 48 h. PPARγ mRNA levels were downregulated after 24 h and upregulated after 48 h of treatment in ADSCs, whereas in MSCs, PPARγ levels were downregulated at both time points. MyoD expression was significantly increased in ADSCs and decreased in MSCs. PPARγ and MyoD protein levels were upregulated in ADSCs and downregulated in MSCs. The CpG methylation levels of the PPARγ and MyoD promoters were decreased in ADSCs and increased in MSCs. Therefore, this study demonstrated that the different regulatory adipogenic roles of MSTN in ADSCs and MSCs act by differentially regulating PPARγ and MyoD expression. - Highlights: • PPARγ and MyoD mRNA and protein levels are upregulated by myostatin in ADSCs. • PPARγ and MyoD mRNA and protein levels are downregulated by myostatin in MSCs. • PPARγ exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • MyoD exhibited different methylation levels in myostatin-treated ADSCs and MSCs. • PPARγ and MyoD are differentially regulated by myostatin in ADSCs and MSCs.

  3. Isolation, Culture, and Immunostaining of Skeletal Muscle Myofibers from Wildtype and Nestin-GFP Mice as a Means to Analyze Satellite Cell.

    Science.gov (United States)

    Stuelsatz, Pascal; Keire, Paul; Yablonka-Reuveni, Zipora

    2017-01-01

    Multinucleated myofibers, the functional contractile units of adult skeletal muscle, harbor mononuclear Pax7(+) myogenic progenitors on their surface between the myofiber basal lamina and plasmalemma. These progenitors, known as satellite cells, are the primary myogenic stem cells in adult muscle. This chapter describes our laboratory protocols for isolating, culturing, and immunostaining intact myofibers from mouse skeletal muscle as a means for studying satellite cell dynamics. The first protocol discusses myofiber isolation from the flexor digitorum brevis (FDB) muscle. These short myofibers are plated in dishes coated with PureCol collagen (formerly known as Vitrogen) and maintained in a mitogen-poor medium (± supplemental growth factors). Employing such conditions, satellite cells remain at the surface of the parent myofiber while synchronously undergoing a limited number of proliferative cycles and rapidly differentiate. The second protocol discusses the isolation of longer myofibers from the extensor digitorum longus (EDL) muscle. These EDL myofibers are routinely plated individually as adherent myofibers in wells coated with Matrigel and maintained in a mitogen-rich medium, conditions in which satellite cells migrate away from the parent myofiber, proliferate extensively, and generate numerous differentiating progeny. Alternatively, these EDL myofibers can be plated as non-adherent myofibers in uncoated wells and maintained in a mitogen-poor medium (± supplemental growth factors), conditions that retain satellite cell progeny at the myofiber niche similar to the FDB myofiber cultures. However, the adherent myofiber format is our preferred choice for monitoring satellite cells in freshly isolated (Time 0) myofibers. We conclude this chapter by promoting the Nestin-GFP transgenic mouse as an efficient tool for direct analysis of satellite cells in isolated myofibers. While satellite cells have been often detected by their expression of the Pax7 protein or

  4. The acute satellite cell response and skeletal muscle hypertrophy following resistance training.

    Directory of Open Access Journals (Sweden)

    Leeann M Bellamy

    Full Text Available The extent of skeletal muscle hypertrophy in response to resistance training is highly variable in humans. The main objective of this study was to explain the nature of this variability. More specifically, we focused on the myogenic stem cell population, the satellite cell (SC as a potential mediator of hypertrophy. Twenty-three males (aged 18-35 yrs participated in 16 wk of progressive, whole body resistance training, resulting in changes of 7.9±1.6% (range of -1.9-24.7% and 21.0±4.0% (range of -7.0 to 51.7% in quadriceps volume and myofibre cross-sectional area (CSA, respectively. The SC response to a single bout of resistance exercise (80% 1RM, analyzed via immunofluorescent staining resulted in an expansion of type II fibre associated SC 72 h following exercise (pre: 11.3±0.9; 72 h: 14.8±1.4 SC/type II fibre; p<0.05. Training resulted in an expansion of the SC pool associated with type I (pre: 10.7±1.1; post: 12.1±1.2 SC/type I fibre; p<0.05 and type II fibres (pre: 11.3±0.9; post: 13.0±1.2 SC/type II fibre; p<0.05. Analysis of individual SC responses revealed a correlation between the relative change in type I associated SC 24 to 72 hours following an acute bout of resistance exercise and the percentage increase in quadriceps lean tissue mass assessed by MRI (r2 = 0.566, p = 0.012 and the relative change in type II associated SC following 16 weeks of resistance training and the percentage increase in quadriceps lean tissue mass assessed by MRI (r2 = 0.493, p = 0.027. Our results suggest that the SC response to resistance exercise is related to the extent of muscular hypertrophy induced by training.

  5. The nanofibrous PAN-PANi scaffold as an efficient substrate for skeletal muscle differentiation using satellite cells.

    Science.gov (United States)

    Hosseinzadeh, Simzar; Mahmoudifard, Matin; Mohamadyar-Toupkanlou, Farzaneh; Dodel, Masomeh; Hajarizadeh, Atena; Adabi, Mahdi; Soleimani, Masoud

    2016-07-01

    Among polymers, polyaniline (PANi) has been introduced as a good candidate for muscle regeneration due to high conductivity and also biocompatibility. Herein, for the first time, we report the use of electrospun nanofibrous membrane of PAN-PANi as efficient scaffold for muscle regeneration. The prepared PAN-PANi electrospun nanofibrous membrane was characterized by scanning electron microscopy (SEM), Attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR) and tensile examination. The softer scaffolds of non-composite electrospun nanofibrous PAN govern a higher rate of cell growth in spite of lower differentiation value. On the other hand, PAN-PANi electrospun nanofibrous membrane exposed high cell proliferation and also differentiation value. Thank to the conductive property and higher Young's modulus of composite type due to the employment of PANi, satellite cells were induced into more matured form as analyzed by Real-Time PCR. On the other hand, grafting of composite nanofibrous electrospun scaffold with gelatin increased the surface stiffness directing satellite cells into lower cell proliferation and highest value of differentiation. Our results for first time showed the significant role of combination between conductivity, mechanical property and surface modification of PAN-PANi electrospun nanofibers and provid new insights into most biocompatible scaffolds for muscle tissue engineering. The schematic figure conveys the effective combination of conductive and surface stiffness on muscle tissue engineering.

  6. Multi-Grid-Cell Validation of Satellite Aerosol Property Retrievals in INTEX/ITCT/ICARTT 2004

    Science.gov (United States)

    Russell, P. B.; Livingston, J. M.; Redemann, J.; Schmid, B.; Ramirez, S. A.; Eilers, J.; Kahn, R.; Chu, D. A.; Remer, L.; Quinn, P. K.; Rood, M. J.; Wang, W.

    2007-01-01

    Aerosol transport off the US Northeast coast during the Summer 2004 International Consortium for Atmospheric Research on Transport and Transformation (ICARTT) Intercontinental Chemical Transport Experiment (INTEX) and Intercontinental Transport and Chemical Transformation (ITCT) experiments produced a wide range of aerosol types and aerosol optical depth (AOD) values, often with strong horizontal AOD gradients. In these conditions we flew the 14-channel NASA Ames Airborne Tracking Sun photometer (AATS) on a Jetstream 31 (J31) aircraft. Legs flown at low altitude (usually less than 100 m ASL) provided comparisons of AATS AOD spectra to retrievals for 90 grid cells of the satellite radiometers MODIS-Terra, MODIS-Aqua, and MISR, all over the ocean. Characterization of the retrieval environment was aided by using vertical profiles by the J31 (showing aerosol vertical structure) and, on occasion, shipboard measurements of light scattering and absorption. AATS provides AOD at 13 wavelengths lambda from 354 to 2138 nm, spanning the range of aerosol retrieval wavelengths for MODIS over ocean (466-2119 nm) and MISR (446-866 nm). Midvisible AOD on low-altitude J31 legs in satellite grid cells ranged from 0.05 to 0.9, with horizontal gradients often in the range 0.05 to 0.13 per 10 km. When possible, we used ship measurements of humidified aerosol scattering and absorption to estimate AOD below the J31. In these cases, which had J31 altitudes 60-110 m ASL (typical of J31 low-altitude transects), estimated midvisible AOD below the J31 ranged from 0.003 to 0.013, with mean 0.009 and standard deviation 0.003. These values averaged 6 percent of AOD above the 53 1. MISR-AATS comparisons on 29 July 2004 in 8 grid cells (each -17.6 km x 17.6 km) show that MISR versions 15 and 16 captured the AATS-measured AOD gradient (correlation coefficient R2 = 0.87 to 0.92), but the MISR gradient was somewhat weaker than the AATS gradient. The large AOD (midvisible values up to -0.9) and

  7. Early-age feed restriction affects viability and gene expression of satellite cells isolated from the gastrocnemius muscle of broiler chicks

    Directory of Open Access Journals (Sweden)

    Li Yue

    2012-11-01

    Full Text Available Abstract Background Muscle growth depends on the fusion of proliferate satellite cells to existing myofibers. We reported previously that 0–14 day intermittent feeding led to persistent retardation in myofiber hypertrophy. However, how satellite cells respond to such nutritional insult has not been adequately elucidated. Results One-day-old broiler chicks were allocated to control (Con, ad libitum feeding, intermittent feeding (IF, feed provided on alternate days and re-feeding (RF, 2 days ad libitum feeding after 12 days of intermittent feeding groups. Chickens were killed on Day 15 and satellite cells were isolated. When cultured, satellite cells from the IF group demonstrated significant retardation in proliferation and differentiation potential, while RF partly restored the proliferation rate and differentiation potential of the satellite cells. Significant up-regulation of insulin like growth factor I receptor (IGF-IR (P0.05 and thyroid hormone receptor α (TRα (P0.05, and down-regulation of growth hormone receptor (GHR (P0.01 and IGF-I (P0.01 mRNA expression was observed in freshly isolated IF satellite cells when compared with Con cells. In RF cells, the mRNA expression of IGF-I was higher (P0.05 and of TRα was lower (P0.01 than in IF cells, suggesting that RF restored the mRNA expression of TRα and IGF-I, but not of GHR and IGF-IR. The Bax/Bcl-2 ratio tended to increase in the IF group, which was reversed in the RF group (P0.05, indicating that RF reduced the pro-apoptotic influence of IF. Moreover, no significant effect of T3 was detected on cell survival in IF cells compared with Con (PP0.05 cells. Conclusions These data suggest that early-age feed restriction inhibits the proliferation and differentiation of satellite cells, induces changes in mRNA expression of the GH/IGF-I and thyroid hormone receptors in satellite cells, as well as blunted sensitivity of satellite cells to T3, and that RF partially reverses these effects. Thus

  8. Fuse Modeling for Reliability Study of Power Electronics Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  9. Fuse Modeling for Reliability Study of Power Electronics Circuits

    DEFF Research Database (Denmark)

    Bahman, Amir Sajjad; Iannuzzo, Francesco; Blaabjerg, Frede

    2017-01-01

    This paper describes a comprehensive modeling approach on reliability of fuses used in power electronic circuits. When fuses are subjected to current pulses, cyclic temperature stress is introduced to the fuse element and will wear out the component. Furthermore, the fuse may be used in a large...

  10. FOXP3+ T Cells Recruited to Sites of Sterile Skeletal Muscle Injury Regulate the Fate of Satellite Cells and Guide Effective Tissue Regeneration

    Science.gov (United States)

    Castiglioni, Alessandra; Basso, Veronica; Vezzoli, Michela; Monno, Antonella; Almada, Albert E.; Mondino, Anna; Wagers, Amy J.; Manfredi, Angelo A.; Rovere-Querini, Patrizia

    2015-01-01

    Muscle injury induces a classical inflammatory response in which cells of the innate immune system rapidly invade the tissue. Macrophages are prominently involved in this response and required for proper healing, as they are known to be important for clearing cellular debris and supporting satellite cell differentiation. Here, we sought to assess the role of the adaptive immune system in muscle regeneration after acute damage. We show that T lymphocytes are transiently recruited into the muscle after damage and appear to exert a pro-myogenic effect on muscle repair. We observed a decrease in the cross-sectional area of regenerating myofibers after injury in Rag2-/- γ-chain-/- mice, as compared to WT controls, suggesting that T cell recruitment promotes muscle regeneration. Skeletal muscle infiltrating T lymphocytes were enriched in CD4+CD25+FOXP3+ cells. Direct exposure of muscle satellite cells to in vitro induced Treg cells effectively enhanced their expansion, and concurrently inhibited their myogenic differentiation. In vivo, the recruitment of Tregs to acutely injured muscle was limited to the time period of satellite expansion, with possibly important implications for situations in which inflammatory conditions persist, such as muscular dystrophies and inflammatory myopathies. We conclude that the adaptive immune system, in particular T regulatory cells, is critically involved in effective skeletal muscle regeneration. Thus, in addition to their well-established role as regulators of the immune/inflammatory response, T regulatory cells also regulate the activity of skeletal muscle precursor cells, and are instrumental for the proper regeneration of this tissue. PMID:26039259

  11. FOXP3+ T Cells Recruited to Sites of Sterile Skeletal Muscle Injury Regulate the Fate of Satellite Cells and Guide Effective Tissue Regeneration.

    Directory of Open Access Journals (Sweden)

    Alessandra Castiglioni

    Full Text Available Muscle injury induces a classical inflammatory response in which cells of the innate immune system rapidly invade the tissue. Macrophages are prominently involved in this response and required for proper healing, as they are known to be important for clearing cellular debris and supporting satellite cell differentiation. Here, we sought to assess the role of the adaptive immune system in muscle regeneration after acute damage. We show that T lymphocytes are transiently recruited into the muscle after damage and appear to exert a pro-myogenic effect on muscle repair. We observed a decrease in the cross-sectional area of regenerating myofibers after injury in Rag2-/- γ-chain-/- mice, as compared to WT controls, suggesting that T cell recruitment promotes muscle regeneration. Skeletal muscle infiltrating T lymphocytes were enriched in CD4+CD25+FOXP3+ cells. Direct exposure of muscle satellite cells to in vitro induced Treg cells effectively enhanced their expansion, and concurrently inhibited their myogenic differentiation. In vivo, the recruitment of Tregs to acutely injured muscle was limited to the time period of satellite expansion, with possibly important implications for situations in which inflammatory conditions persist, such as muscular dystrophies and inflammatory myopathies. We conclude that the adaptive immune system, in particular T regulatory cells, is critically involved in effective skeletal muscle regeneration. Thus, in addition to their well-established role as regulators of the immune/inflammatory response, T regulatory cells also regulate the activity of skeletal muscle precursor cells, and are instrumental for the proper regeneration of this tissue.

  12. FOXP3+ T Cells Recruited to Sites of Sterile Skeletal Muscle Injury Regulate the Fate of Satellite Cells and Guide Effective Tissue Regeneration.

    Science.gov (United States)

    Castiglioni, Alessandra; Corna, Gianfranca; Rigamonti, Elena; Basso, Veronica; Vezzoli, Michela; Monno, Antonella; Almada, Albert E; Mondino, Anna; Wagers, Amy J; Manfredi, Angelo A; Rovere-Querini, Patrizia

    2015-01-01

    Muscle injury induces a classical inflammatory response in which cells of the innate immune system rapidly invade the tissue. Macrophages are prominently involved in this response and required for proper healing, as they are known to be important for clearing cellular debris and supporting satellite cell differentiation. Here, we sought to assess the role of the adaptive immune system in muscle regeneration after acute damage. We show that T lymphocytes are transiently recruited into the muscle after damage and appear to exert a pro-myogenic effect on muscle repair. We observed a decrease in the cross-sectional area of regenerating myofibers after injury in Rag2-/- γ-chain-/- mice, as compared to WT controls, suggesting that T cell recruitment promotes muscle regeneration. Skeletal muscle infiltrating T lymphocytes were enriched in CD4+CD25+FOXP3+ cells. Direct exposure of muscle satellite cells to in vitro induced Treg cells effectively enhanced their expansion, and concurrently inhibited their myogenic differentiation. In vivo, the recruitment of Tregs to acutely injured muscle was limited to the time period of satellite expansion, with possibly important implications for situations in which inflammatory conditions persist, such as muscular dystrophies and inflammatory myopathies. We conclude that the adaptive immune system, in particular T regulatory cells, is critically involved in effective skeletal muscle regeneration. Thus, in addition to their well-established role as regulators of the immune/inflammatory response, T regulatory cells also regulate the activity of skeletal muscle precursor cells, and are instrumental for the proper regeneration of this tissue.

  13. Glucagon like peptide-1-induced glucose metabolism in differentiated human muscle satellite cells is attenuated by hyperglycemia.

    Directory of Open Access Journals (Sweden)

    Charlotte J Green

    Full Text Available BACKGROUND: Glucagon like peptide-1 (GLP-1 stimulates insulin secretion from the pancreas but also has extra-pancreatic effects. GLP-1 may stimulate glucose uptake in cultured muscle cells but the mechanism is not clearly defined. Furthermore, while the pancreatic effects of GLP-1 are glucose-dependent, the glucose-dependency of its extra-pancreatic effects has not been examined. METHODS: Skeletal muscle satellite cells isolated from young (22.5 ± 0.97 yr, lean (BMI 22.5 ± 0.6 kg/m(2, healthy males were differentiated in media containing either 22.5 mM (high or 5 mM (normal glucose for 7 days in the absence or presence of insulin and/or various GLP-1 concentrations. Myocellular effects of GLP-1, insulin and glucose were assessed by western-blot, glucose uptake and glycogen synthesis. RESULTS: We firstly show that the GLP-1 receptor protein is expressed in differentiated human muscle satellite cells (myocytes. Secondly, we show that in 5 mM glucose media, exposure of myocytes to GLP-1 results in a dose dependent increase in glucose uptake, GLUT4 amount and subsequently glycogen synthesis in a PI3K dependent manner, independent of the insulin signaling cascade. Importantly, we provide evidence that differentiation of human satellite cells in hyperglycemic (22.5 mM glucose conditions increases GLUT1 expression, and renders the cells insulin resistant and interestingly GLP-1 resistant in terms of glucose uptake and glycogen synthesis. Hyperglycemic conditions did not affect the ability of insulin to phosphorylate downstream targets, PKB or GSK3. Interestingly we show that at 5 mM glucose, GLP-1 increases GLUT4 protein levels and that this effect is abolished by hyperglycemia. CONCLUSIONS: GLP-1 increases glucose uptake and glycogen synthesis into fully-differentiated human satellite cells in a PI3-K dependent mechanism potentially through increased GLUT4 protein levels. The latter occurs independently of the insulin signaling pathway. Attenuation

  14. To fuse or not to fuse: what is your purpose?

    Science.gov (United States)

    Bell, Mark R; Engleka, Mark J; Malik, Asim; Strickler, James E

    2013-11-01

    Since the dawn of time, or at least the dawn of recombinant DNA technology (which for many of today's scientists is the same thing), investigators have been cloning and expressing heterologous proteins in a variety of different cells for a variety of different reasons. These range from cell biological studies looking at protein-protein interactions, post-translational modifications, and regulation, to laboratory-scale production in support of biochemical, biophysical, and structural studies, to large scale production of potential biotherapeutics. In parallel, fusion-tag technology has grown-up to facilitate microscale purification (pull-downs), protein visualization (epitope tags), enhanced expression and solubility (protein partners, e.g., GST, MBP, TRX, and SUMO), and generic purification (e.g., His-tags, streptag, and FLAG™-tag). Frequently, these latter two goals are combined in a single fusion partner. In this review, we examine the most commonly used fusion methodologies from the perspective of the ultimate use of the tagged protein. That is, what are the most commonly used fusion partners for pull-downs, for structural studies, for production of active proteins, or for large-scale purification? What are the advantages and limitations of each? This review is not meant to be exhaustive and the approach undoubtedly reflects the experiences and interests of the authors. For the sake of brevity, we have largely ignored epitope tags although they receive wide use in cell biology for immunopreciptation.

  15. Wafer-fused semiconductor radiation detector

    Science.gov (United States)

    Lee, Edwin Y.; James, Ralph B.

    2002-01-01

    Wafer-fused semiconductor radiation detector useful for gamma-ray and x-ray spectrometers and imaging systems. The detector is fabricated using wafer fusion to insert an electrically conductive grid, typically comprising a metal, between two solid semiconductor pieces, one having a cathode (negative electrode) and the other having an anode (positive electrode). The wafer fused semiconductor radiation detector functions like the commonly used Frisch grid radiation detector, in which an electrically conductive grid is inserted in high vacuum between the cathode and the anode. The wafer-fused semiconductor radiation detector can be fabricated using the same or two different semiconductor materials of different sizes and of the same or different thicknesses; and it may utilize a wide range of metals, or other electrically conducting materials, to form the grid, to optimize the detector performance, without being constrained by structural dissimilarity of the individual parts. The wafer-fused detector is basically formed, for example, by etching spaced grooves across one end of one of two pieces of semiconductor materials, partially filling the grooves with a selected electrical conductor which forms a grid electrode, and then fusing the grooved end of the one semiconductor piece to an end of the other semiconductor piece with a cathode and an anode being formed on opposite ends of the semiconductor pieces.

  16. OPUS: the FUSE science data pipeline

    Science.gov (United States)

    Rose, James F.; Heller-Boyer, C.; Rose, M. A.; Swam, M.; Miller, W.; Kriss, G. A.; Oegerle, William R.

    1998-07-01

    This paper describes how the OPUS pipeline, currently used for processing science data from the Hubble Space Telescope (HST), was used as the backbone for developing the science data pipeline for a much smaller mission. The far ultraviolet spectroscopic explorer (FUSE) project selected OPUS for its data processing pipeline platform and selected the OPUS team at the STScI to write the FUSE pipeline applications. A total of 105 new modules were developed for the FUSE pipeline. The foundation of over 250 modules in the OPUS libraries allowed development to proceed quickly and with considerable confidence that the underlying functionality is reliable and robust. Each task represented roughly 90 percent reuse, and the project as a whole shows over 70 percent reuse of the existing OPUS system. Taking an existing system that is operational, and will be maintained for many years to come, was a key decision for the FUSE mission. Adding the extensive experience of the OPUS team to the task resulted in the development of a complete telemetry pipeline system within a matter of months. Reusable software has been the siren song of software engineering and object- oriented design for a decade or more. The development of inexpensive software systems by adapting existing code to new applications is as attractive as it has been elusive. The OPUS telemetry pipeline for the FUSE mission has proven to be a significant exception to that trend.

  17. Expression of CCAAT/Enhancer Binding Protein Beta in Muscle Satellite Cells Inhibits Myogenesis in Cancer Cachexia.

    Science.gov (United States)

    Marchildon, François; Lamarche, Émilie; Lala-Tabbert, Neena; St-Louis, Catherine; Wiper-Bergeron, Nadine

    2015-01-01

    Cancer cachexia is a paraneoplastic syndrome that causes profound weight loss and muscle mass atrophy and is estimated to be the cause of up to 30% of cancer deaths. Though the exact cause is unknown, patients with cancer cachexia have increased muscle protein catabolism. In healthy muscle, injury activates skeletal muscle stem cells, called satellite cells, to differentiate and promote regeneration. Here, we provide evidence that this mechanism is inhibited in cancer cachexia due to persistent expression of CCAAT/Enhancer Binding Protein beta (C/EBPβ) in muscle myoblasts. C/EBPβ is a bzip transcription factor that is expressed in muscle satellite cells and is normally downregulated upon differentiation. However, in myoblasts exposed to a cachectic milieu, C/EBPβ expression remains elevated, despite activation to differentiate, resulting in the inhibition of myogenin expression and myogenesis. In vivo, cancer cachexia results in increased number of Pax7+ cells that also express C/EBPβ and the inhibition of normal repair mechanisms. Loss of C/EBPβ expression in primary myoblasts rescues differentiation under cachectic conditions without restoring myotube size, indicating that C/EBPβ is an important inhibitor of myogenesis in cancer cachexia.

  18. Expression of cassini, a murine gamma-satellite sequence conserved in evolution, is regulated in normal and malignant hematopoietic cells

    Directory of Open Access Journals (Sweden)

    Arutyunyan Anna

    2012-08-01

    Full Text Available Abstract Background Acute lymphoblastic leukemia (ALL cells treated with drugs can become drug-tolerant if co-cultured with protective stromal mouse embryonic fibroblasts (MEFs. Results We performed transcriptional profiling on these stromal fibroblasts to investigate if they were affected by the presence of drug-treated ALL cells. These mitotically inactivated MEFs showed few changes in gene expression, but a family of sequences of which transcription is significantly increased was identified. A sequence related to this family, which we named cassini, was selected for further characterization. We found that cassini was highly upregulated in drug-treated ALL cells. Analysis of RNAs from different normal mouse tissues showed that cassini expression is highest in spleen and thymus, and can be further enhanced in these organs by exposure of mice to bacterial endotoxin. Heat shock, but not other types of stress, significantly induced the transcription of this locus in ALL cells. Transient overexpression of cassini in human 293 embryonic kidney cells did not increase the cytotoxic or cytostatic effects of chemotherapeutic drugs but provided some protection. Database searches revealed that sequences highly homologous to cassini are present in rodents, apicomplexans, flatworms and primates, indicating that they are conserved in evolution. Moreover, CASSINI RNA was induced in human ALL cells treated with vincristine. Surprisingly, cassini belongs to the previously reported murine family of γ-satellite/major satellite DNA sequences, which were not known to be present in other species. Conclusions Our results show that the transcription of at least one member of these sequences is regulated, suggesting that this has a function in normal and transformed immune cells. Expression of these sequences may protect cells when they are exposed to specific stress stimuli.

  19. Expression of cassini, a murine gamma-satellite sequence conserved in evolution, is regulated in normal and malignant hematopoietic cells.

    Science.gov (United States)

    Arutyunyan, Anna; Stoddart, Sonia; Yi, Sun-ju; Fei, Fei; Lim, Min; Groffen, Paula; Feldhahn, Niklas; Groffen, John; Heisterkamp, Nora

    2012-08-23

    Acute lymphoblastic leukemia (ALL) cells treated with drugs can become drug-tolerant if co-cultured with protective stromal mouse embryonic fibroblasts (MEFs). We performed transcriptional profiling on these stromal fibroblasts to investigate if they were affected by the presence of drug-treated ALL cells. These mitotically inactivated MEFs showed few changes in gene expression, but a family of sequences of which transcription is significantly increased was identified. A sequence related to this family, which we named cassini, was selected for further characterization. We found that cassini was highly upregulated in drug-treated ALL cells. Analysis of RNAs from different normal mouse tissues showed that cassini expression is highest in spleen and thymus, and can be further enhanced in these organs by exposure of mice to bacterial endotoxin. Heat shock, but not other types of stress, significantly induced the transcription of this locus in ALL cells. Transient overexpression of cassini in human 293 embryonic kidney cells did not increase the cytotoxic or cytostatic effects of chemotherapeutic drugs but provided some protection. Database searches revealed that sequences highly homologous to cassini are present in rodents, apicomplexans, flatworms and primates, indicating that they are conserved in evolution. Moreover, CASSINI RNA was induced in human ALL cells treated with vincristine. Surprisingly, cassini belongs to the previously reported murine family of γ-satellite/major satellite DNA sequences, which were not known to be present in other species. Our results show that the transcription of at least one member of these sequences is regulated, suggesting that this has a function in normal and transformed immune cells. Expression of these sequences may protect cells when they are exposed to specific stress stimuli.

  20. Implantation of muscle satellite cells overexpressing myogenin improves denervated muscle atrophy in rats

    Directory of Open Access Journals (Sweden)

    H. Shen

    2016-01-01

    Full Text Available This study evaluated the effect of muscle satellite cells (MSCs overexpressing myogenin (MyoG on denervated muscle atrophy. Rat MSCs were isolated and transfected with the MyoG-EGFP plasmid vector GV143. MyoG-transfected MSCs (MTMs were transplanted into rat gastrocnemius muscles at 1 week after surgical denervation. Controls included injections of untransfected MSCs or the vehicle only. Muscles were harvested and analyzed at 2, 4, and 24 weeks post-transplantation. Immunofluorescence confirmed MyoG overexpression in MTMs. The muscle wet weight ratio was significantly reduced at 2 weeks after MTM injection (67.17±6.79 compared with muscles injected with MSCs (58.83±5.31 or the vehicle (53.00±7.67; t=2.37, P=0.04 and t=3.39, P=0.007, respectively. The muscle fiber cross-sectional area was also larger at 2 weeks after MTM injection (2.63×103±0.39×103 compared with MSC injection (1.99×103±0.58×103 or the vehicle only (1.57×103±0.47×103; t=2.24, P=0.049 and t=4.22, P=0.002, respectively. At 4 and 24 weeks post-injection, the muscle mass and fiber cross-sectional area were similar across all three experimental groups. Immunohistochemistry showed that the MTM group had larger MyoG-positive fibers. The MTM group (3.18±1.13 also had higher expression of MyoG mRNA than other groups (1.41±0.65 and 1.03±0.19 at 2 weeks after injection (t=2.72, P=0.04. Transplanted MTMs delayed short-term atrophy of denervated muscles. This approach can be optimized as a novel stand-alone therapy or as a bridge to surgical re-innervation of damaged muscles.

  1. Implantation of muscle satellite cells overexpressing myogenin improves denervated muscle atrophy in rats.

    Science.gov (United States)

    Shen, H; Lv, Y; Shen, X Q; Xu, J H; Lu, H; Fu, L C; Duan, T

    2016-02-01

    This study evaluated the effect of muscle satellite cells (MSCs) overexpressing myogenin (MyoG) on denervated muscle atrophy. Rat MSCs were isolated and transfected with the MyoG-EGFP plasmid vector GV143. MyoG-transfected MSCs (MTMs) were transplanted into rat gastrocnemius muscles at 1 week after surgical denervation. Controls included injections of untransfected MSCs or the vehicle only. Muscles were harvested and analyzed at 2, 4, and 24 weeks post-transplantation. Immunofluorescence confirmed MyoG overexpression in MTMs. The muscle wet weight ratio was significantly reduced at 2 weeks after MTM injection (67.17±6.79) compared with muscles injected with MSCs (58.83±5.31) or the vehicle (53.00±7.67; t=2.37, P=0.04 and t=3.39, P=0.007, respectively). The muscle fiber cross-sectional area was also larger at 2 weeks after MTM injection (2.63×10³±0.39×10³) compared with MSC injection (1.99×10³±0.58×10³) or the vehicle only (1.57×10³±0.47×10³; t=2.24, P=0.049 and t=4.22, P=0.002, respectively). At 4 and 24 weeks post-injection, the muscle mass and fiber cross-sectional area were similar across all three experimental groups. Immunohistochemistry showed that the MTM group had larger MyoG-positive fibers. The MTM group (3.18±1.13) also had higher expression of MyoG mRNA than other groups (1.41±0.65 and 1.03±0.19) at 2 weeks after injection (t=2.72, P=0.04). Transplanted MTMs delayed short-term atrophy of denervated muscles. This approach can be optimized as a novel stand-alone therapy or as a bridge to surgical re-innervation of damaged muscles.

  2. Endodontic and post-endodontic management of a fused molar

    Directory of Open Access Journals (Sweden)

    Ruchi Gupta

    2013-01-01

    Full Text Available Treatment of fused teeth needs special care and attention to the bizarre anatomy. This paper describes root canal treatment of a fused carious tooth presenting with apical periodontitis. It is a rare case of fusion of the mandibular second molar with a paramolar. There is no literature regarding placement of crown over endodontically treated fused teeth. In this case, the fused teeth were endodontically treated and restored by a porcelain fused to metal crown.

  3. Fused silica windows for solar receiver applications

    Science.gov (United States)

    Hertel, Johannes; Uhlig, Ralf; Söhn, Matthias; Schenk, Christian; Helsch, Gundula; Bornhöft, Hansjörg

    2016-05-01

    A comprehensive study of optical and mechanical properties of quartz glass (fused silica) with regard to application in high temperature solar receivers is presented. The dependence of rupture strength on different surface conditions as well as high temperature is analyzed, focussing particularly on damage by devitrification and sandblasting. The influence of typical types of contamination in combination with thermal cycling on the optical properties of fused silica is determined. Cleaning methods are compared regarding effectiveness on contamination-induced degradation for samples with and without antireflective coating. The FEM-aided design of different types of receiver windows and their support structure is presented. A large-scale production process has been developed for producing fused silica dome shaped windows (pressurized window) up to a diameter of 816 mm. Prototypes were successfully pressure-tested in a test bench and certified according to the European Pressure Vessel Directive.

  4. Fusing Facial Features for Face Recognition

    Directory of Open Access Journals (Sweden)

    Jamal Ahmad Dargham

    2012-06-01

    Full Text Available Face recognition is an important biometric method because of its potential applications in many fields, such as access control, surveillance, and human-computer interaction. In this paper, a face recognition system that fuses the outputs of three face recognition systems based on Gabor jets is presented. The first system uses the magnitude, the second uses the phase, and the third uses the phase-weighted magnitude of the jets. The jets are generated from facial landmarks selected using three selection methods. It was found out that fusing the facial features gives better recognition rate than either facial feature used individually regardless of the landmark selection method.

  5. Nitric oxide synthase inhibition delays low-frequency stimulation-induced satellite cell activation in rat fast-twitch muscle.

    Science.gov (United States)

    Martins, Karen J B; MacLean, Ian; Murdoch, Gordon K; Dixon, Walter T; Putman, Charles T

    2011-12-01

    This study examined the effect of nitric oxide synthase (NOS) inhibition via N(ω)-nitro-l-arginine methyl ester (l-NAME) administration on low-frequency stimulation-induced satellite cell (SC) activation in rat skeletal muscle. l-NAME only delayed stimulation-induced increases in SC activity. Also, stimulation-induced increases in hepatocyte growth factor (HGF) mRNA and protein expression were only abrogated at the mRNA level in l-NAME-treated animals. Therefore, early stimulation-induced SC activation appears to be NOS-dependent, while continued activation may involve NOS-independent HGF translational control mechanisms.

  6. Perineuronal satellite neuroglia in the telencephalon of New Caledonian crows and other Passeriformes: evidence of satellite glial cells in the central nervous system of healthy birds?

    Science.gov (United States)

    Medina, Felipe S; Hunt, Gavin R; Gray, Russell D; Wild, J Martin; Kubke, M Fabiana

    2013-01-01

    Glia have been implicated in a variety of functions in the central nervous system, including the control of the neuronal extracellular space, synaptic plasticity and transmission, development and adult neurogenesis. Perineuronal glia forming groups around neurons are associated with both normal and pathological nervous tissue. Recent studies have linked reduction in the number of perineuronal oligodendrocytes in the prefrontal cortex with human schizophrenia and other psychiatric disorders. Therefore, perineuronal glia may play a decisive role in homeostasis and normal activity of the human nervous system. Here we report on the discovery of novel cell clusters in the telencephala of five healthy Passeriforme, one Psittaciform and one Charadriiforme bird species, which we refer to as Perineuronal Glial Clusters (PGCs). The aim of this study is to describe the structure and distribution of the PGCs in a number of avian species. PGCs were identified with the use of standard histological procedures. Heterochromatin masses visible inside the nuclei of these satellite glia suggest that they may correspond to oligodendrocytes. PGCs were found in the brains of nine New Caledonian crows, two Japanese jungle crows, two Australian magpies, two Indian mynah, three zebra finches (all Passeriformes), one Southern lapwing (Charadriiformes) and one monk parakeet (Psittaciformes). Microscopic survey of the brain tissue suggests that the largest PGCs are located in the hyperpallium densocellulare and mesopallium. No clusters were found in brain sections from one Gruiform (purple swamphen), one Strigiform (barn owl), one Trochiliform (green-backed firecrown), one Falconiform (chimango caracara), one Columbiform (pigeon) and one Galliform (chick). Our observations suggest that PGCs in Aves are brain region- and taxon-specific and that the presence of perineuronal glia in healthy human brains and the similar PGCs in avian gray matter is the result of convergent evolution. The discovery

  7. Fungal Systematics and Evolution: FUSE 1

    NARCIS (Netherlands)

    Crous, Pedro W; Schumacher, René K; Wingfield, Michael J; Lombard, Lorenzo; Giraldo, Alejandra; Christensen, Martha; Gardiennet, Alain; Nakashima, Chiharu; Pereira, Olinto L; Smith, Alexander J; Groenewald, Johannes Z

    2015-01-01

    Fungal Systematics and Evolution (FUSE) is introduced as a new series to expedite the publication of issues relating to the epitypification of formerly described species, report new sexual-asexual connections, the merging of sexual and asexual gen¬era following the end of dual nomenclature, and to

  8. Renovating a Fusee Ceramique Barrel Vault

    NARCIS (Netherlands)

    Kamerling, M.W.

    2015-01-01

    This paper describes a proposal to renovate a Fusee Ceramique Barrel Vault with steel diagonals In 1956 two workshops, varying in height and span, were built in Wormerveer, The Netherlands. Both workshops were roofed with a concrete barrel vault with a thickness of 110 mm. The cylindrical vaults w

  9. 30 CFR 56.6502 - Safety fuse.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Safety fuse. 56.6502 Section 56.6502 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... initiation systems, igniter cord and connectors, or other nonelectric initiation systems shall be used...

  10. Demonstrating Earth Connections and Fuses Working Together

    Science.gov (United States)

    Harrison, Mark

    2017-01-01

    Earth wires and fuses work together in UK mains circuits to keep users safe from electric shocks and are taught in many school contexts. The subject can be quite abstract and difficult for pupils to grasp, and a simple but visually clear and direct demonstration is described which would be easy for most physics departments to build and which can…

  11. Solar photovoltaic research and development program of the Air Force Aero Propulsion Laboratory. [silicon solar cell applicable to satellite power systems

    Science.gov (United States)

    Wise, J.

    1979-01-01

    Progress is reported in the following areas: laser weapon effects, solar silicon solar cell concepts, and high voltage hardened, high power system technology. Emphasis is placed on solar cells with increased energy conversion efficiency and radiation resistance characteristics for application to satellite power systems.

  12. Perineuronal satellite neuroglia in the telencephalon of New Caledonian crows and other Passeriformes: evidence of satellite glial cells in the central nervous system of healthy birds?

    Directory of Open Access Journals (Sweden)

    Felipe S. Medina

    2013-07-01

    Full Text Available Glia have been implicated in a variety of functions in the central nervous system, including the control of the neuronal extracellular space, synaptic plasticity and transmission, development and adult neurogenesis. Perineuronal glia forming groups around neurons are associated with both normal and pathological nervous tissue. Recent studies have linked reduction in the number of perineuronal oligodendrocytes in the prefrontal cortex with human schizophrenia and other psychiatric disorders. Therefore, perineuronal glia may play a decisive role in homeostasis and normal activity of the human nervous system.Here we report on the discovery of novel cell clusters in the telencephala of five healthy Passeriforme, one Psittaciform and one Charadriiforme bird species, which we refer to as Perineuronal Glial Clusters (PGCs. The aim of this study is to describe the structure and distribution of the PGCs in a number of avian species.PGCs were identified with the use of standard histological procedures. Heterochromatin masses visible inside the nuclei of these satellite glia suggest that they may correspond to oligodendrocytes. PGCs were found in the brains of nine New Caledonian crows, two Japanese jungle crows, two Australian magpies, two Indian mynah, three zebra finches (all Passeriformes, one Southern lapwing (Charadriiformes and one monk parakeet (Psittaciformes. Microscopic survey of the brain tissue suggests that the largest PGCs are located in the hyperpallium densocellulare and mesopallium. No clusters were found in brain sections from one Gruiform (purple swamphen, one Strigiform (barn owl, one Trochiliform (green-backed firecrown, one Falconiform (chimango caracara, one Columbiform (pigeon and one Galliform (chick.Our observations suggest that PGCs in Aves are brain region- and taxon-specific and that the presence of perineuronal glia in healthy human brains and the similar PGCs in avian gray matter is the result of convergent evolution. The

  13. Insulin-like growth factor-I extends in vitro replicative life span of skeletal muscle satellite cells by enhancing G1/S cell cycle progression via the activation of phosphatidylinositol 3'-kinase/Akt signaling pathway

    Science.gov (United States)

    Chakravarthy, M. V.; Abraha, T. W.; Schwartz, R. J.; Fiorotto, M. L.; Booth, F. W.

    2000-01-01

    Interest is growing in methods to extend replicative life span of non-immortalized stem cells. Using the insulin-like growth factor I (IGF-I) transgenic mouse in which the IGF-I transgene is expressed during skeletal muscle development and maturation prior to isolation and during culture of satellite cells (the myogenic stem cells of mature skeletal muscle fibers) as a model system, we elucidated the underlying molecular mechanisms of IGF-I-mediated enhancement of proliferative potential of these cells. Satellite cells from IGF-I transgenic muscles achieved at least five additional population doublings above the maximum that was attained by wild type satellite cells. This IGF-I-induced increase in proliferative potential was mediated via activation of the phosphatidylinositol 3'-kinase/Akt pathway, independent of mitogen-activated protein kinase activity, facilitating G(1)/S cell cycle progression via a down-regulation of p27(Kip1). Adenovirally mediated ectopic overexpression of p27(Kip1) in exponentially growing IGF-I transgenic satellite cells reversed the increase in cyclin E-cdk2 kinase activity, pRb phosphorylation, and cyclin A protein abundance, thereby implicating an important role for p27(Kip1) in promoting satellite cell senescence. These observations provide a more complete dissection of molecular events by which increased local expression of a growth factor in mature skeletal muscle fibers extends replicative life span of primary stem cells than previously known.

  14. Insulin-like growth factor-I extends in vitro replicative life span of skeletal muscle satellite cells by enhancing G1/S cell cycle progression via the activation of phosphatidylinositol 3'-kinase/Akt signaling pathway

    Science.gov (United States)

    Chakravarthy, M. V.; Abraha, T. W.; Schwartz, R. J.; Fiorotto, M. L.; Booth, F. W.

    2000-01-01

    Interest is growing in methods to extend replicative life span of non-immortalized stem cells. Using the insulin-like growth factor I (IGF-I) transgenic mouse in which the IGF-I transgene is expressed during skeletal muscle development and maturation prior to isolation and during culture of satellite cells (the myogenic stem cells of mature skeletal muscle fibers) as a model system, we elucidated the underlying molecular mechanisms of IGF-I-mediated enhancement of proliferative potential of these cells. Satellite cells from IGF-I transgenic muscles achieved at least five additional population doublings above the maximum that was attained by wild type satellite cells. This IGF-I-induced increase in proliferative potential was mediated via activation of the phosphatidylinositol 3'-kinase/Akt pathway, independent of mitogen-activated protein kinase activity, facilitating G(1)/S cell cycle progression via a down-regulation of p27(Kip1). Adenovirally mediated ectopic overexpression of p27(Kip1) in exponentially growing IGF-I transgenic satellite cells reversed the increase in cyclin E-cdk2 kinase activity, pRb phosphorylation, and cyclin A protein abundance, thereby implicating an important role for p27(Kip1) in promoting satellite cell senescence. These observations provide a more complete dissection of molecular events by which increased local expression of a growth factor in mature skeletal muscle fibers extends replicative life span of primary stem cells than previously known.

  15. Textiles: Some technocal information and data VI: fusing

    CSIR Research Space (South Africa)

    Cawood, MP

    1980-09-01

    Full Text Available results. However, complaints of problem do occur particularly with the technology becoming more sophisticated. Fusing interlinings are coated with an adhesive which enables them to be fused under certain conditions of temperature, time and pressure onto...

  16. Myofiber-specific TEAD1 overexpression drives satellite cell hyperplasia and counters pathological effects of dystrophin deficiency

    Science.gov (United States)

    Southard, Sheryl; Kim, Ju-Ryoung; Low, SiewHui; Tsika, Richard W; Lepper, Christoph

    2016-01-01

    When unperturbed, somatic stem cells are poised to affect immediate tissue restoration upon trauma. Yet, little is known regarding the mechanistic basis controlling initial and homeostatic ‘scaling’ of stem cell pool sizes relative to their target tissues for effective regeneration. Here, we show that TEAD1-expressing skeletal muscle of transgenic mice features a dramatic hyperplasia of muscle stem cells (i.e. satellite cells, SCs) but surprisingly without affecting muscle tissue size. Super-numeral SCs attain a ‘normal’ quiescent state, accelerate regeneration, and maintain regenerative capacity over several injury-induced regeneration bouts. In dystrophic muscle, the TEAD1 transgene also ameliorated the pathology. We further demonstrate that hyperplastic SCs accumulate non-cell-autonomously via signal(s) from the TEAD1-expressing myofiber, suggesting that myofiber-specific TEAD1 overexpression activates a physiological signaling pathway(s) that determines initial and homeostatic SC pool size. We propose that TEAD1 and its downstream effectors are medically relevant targets for enhancing muscle regeneration and ameliorating muscle pathology. DOI: http://dx.doi.org/10.7554/eLife.15461.001 PMID:27725085

  17. Concomitant expression of far upstream element (FUSE) binding protein (FBP) interacting repressor (FIR) and its splice variants induce migration and invasion of non-small cell lung cancer (NSCLC) cells.

    Science.gov (United States)

    Müller, Benedikt; Bovet, Michael; Yin, Yi; Stichel, Damian; Malz, Mona; González-Vallinas, Margarita; Middleton, Alistair; Ehemann, Volker; Schmitt, Jennifer; Muley, Thomas; Meister, Michael; Herpel, Esther; Singer, Stephan; Warth, Arne; Schirmacher, Peter; Drasdo, Dirk; Matthäus, Franziska; Breuhahn, Kai

    2015-11-01

    Transcription factors integrate a variety of oncogenic input information, facilitate tumour growth and cell dissemination, and therefore represent promising therapeutic target structures. Because over-expression of DNA-interacting far upstream element binding protein (FBP) supports non-small cell lung cancer (NSCLC) migration, we asked whether its repressor, FBP-interacting repressor (FIR) is functionally inactivated and how FIR might affect NSCLC cell biology. Different FIR splice variants were highly expressed in the majority of NSCLCs, with the highest levels in tumours carrying genomic gains of chromosome 8q24.3, which contained the FIR gene locus. Nuclear FIR expression was significantly enriched at the invasion front of primary NSCLCs, but this did not correlate with tumour cell proliferation. FIR accumulation was associated with worse patient survival and tumour recurrence; in addition, FIR over-expression significantly correlated with lymph node metastasis in squamous cell carcinomas (SCCs). In vitro, we applied newly developed methods and modelling approaches for the quantitative and time-resolved description of the pro-migratory and pro-invasive capacities of SCC cells. siRNA-mediated silencing of all FIR variants significantly reduced the speed and directional movement of tumour cells in all phases of migration. Furthermore, sprouting efficiency and single cell invasiveness were diminished following FIR inhibition. Interestingly, the silencing of FIR isoforms lacking exon 2 (FIR(Δexon2)) alone was sufficient to reduce lateral migration and invasion. In summary, by using scale-spanning data derived from primary human tissues, quantitative cellular analyses and mathematical modelling, we have demonstrated that concomitant over-expression of FIR and its splice variants drives NSCLC migration and dissemination.

  18. Short-term ursolic acid promotes skeletal muscle rejuvenation through enhancing of SIRT1 expression and satellite cells proliferation.

    Science.gov (United States)

    Bakhtiari, Nuredin; Hosseinkhani, Saman; Soleimani, Masoud; Hemmati, Roohullah; Noori-Zadeh, Ali; Javan, Mohammad; Tashakor, Amin

    2016-03-01

    Ursolic acid (UA) is a triterpenoid compound, which exerts its influences on the skeletal muscles. However, the mechanisms underlying these effects are still unclear. In this study, muscle satellite cells were isolated and purified by high-throughput pre-plating method (∼>60%) from 10 days old mice skeletal muscles. Evaluation of paired-box 7 (Pax7) expressions then confirmed the purification. Treatment of the cells with UA showed that UA up-regulated SIRT1 (∼35 folds) and overexpressed PGC-1α (∼175 folds) gene significantly. Moreover, the number of muscle satellite cells, which accompanied by initiation of neomyogenesis in the animal skeletal muscles, was increased (∼3.4 times). We also evaluated UA-mediated changes in the cellular energy status in the skeletal muscles. The results revealed that in the UA-treated mice, ATP and ADP contents in the various skeletal muscle tissue types, including: Gastrocnemius (Gas), Tibialis Anterior (Tib) and Gluteus Maximus (Glu) have been significantly decreased (P≤0.001); 2.2, 3.2, 2 times for ATP, and 9.6, 35.7, 11.6 times for ADP, respectively; however to compensate this process mitochondrial biogenesis occurred (12.33%±1.5 times). Furthermore, a rise in ATP/ADP ratio was observed 2.5, 4.5, 2.05 times for Gas, Tib and Glu muscles, respectively (P≤0.001). Alternatively, UA enhanced the expression of myoglobin (∼2 folds) in concert with remodeling of glycolytic muscle fibers to mainly fast IIA (∼30%) and slow-twitch (∼4%) types as well. Finally, our study indicated that UA indirectly mimicked beneficial effects of short-term calorie restriction and exercise (fast-oxidative) by directing the skeletal muscle composition toward oxidative metabolism.

  19. Multimodal Plasmonics in Fused Colloidal Networks

    CERN Document Server

    Teulle, Alexandre; Girard, C; Gurunatha, Kargal L; Li, Mei; Mann, Stephen; Dujardin, Erik

    2014-01-01

    Harnessing the optical properties of noble metals down to the nanometer-scale is a key step towards fast and low-dissipative information processing. At the 10-nm length scale, metal crystallinity and patterning as well as probing of surface plasmon (SP) properties must be controlled with a challenging high level of precision. Here, we demonstrate that ultimate lateral confinement and delocalization of SP modes are simultaneously achieved in extended self-assembled networks comprising linear chains of partially fused gold nanoparticles. The spectral and spatial distributions of the SP modes associated with the colloidal superstructures are evidenced by performing monochromated electron energy loss spectroscopy with a nanometer-sized electron probe. We prepare the metallic bead strings by electron beam-induced interparticle fusion of nanoparticle networks. The fused superstructures retain the native morphology and crystallinity but develop very low energy SP modes that are capable of supporting long range and s...

  20. Pressure evolution during HBC fuse operation

    Energy Technology Data Exchange (ETDEWEB)

    Rochette, D; Bussiere, W [Laboratoire Arc Electrique et Plasmas Thermiques (LAEPT)-CNRS UMR 6069, Universite Blaise Pascal, 24 Avenue des Landais, F 63177 Aubiere Cedex (France)

    2004-05-01

    The purpose of this paper is to describe the influence of the silica sand grains on pressure during the energy release in a high breaking capacity (HBC) fuse. During the HBC fuse operation, the pressure evolution is the result of two opposite trends: the pressure increase due to the interaction of the silica plasma with the surrounding granular sand, and the pressure decrease due to the propagation of the pressure waves toward the porous medium. Due to the complex phenomena occurring during the current extinction by a fuse, two kinds of pressure are distinguished: the pressure inside the silica plasma and the pressure in the silica sand. From the simulations we show that the Forchheimer flow resistance is stronger than the Darcy flow resistance once the electric power is over 30% of the maximum value. A comparison of the calculated and measured pressures is made at various positions from the fuse element axis. Two different pressures are obtained experimentally: the pressure P{sub SAND} exerted on the sand grains due to the plasma pressure, and the pressure P{sub GAS} of the gas flowing through the interstices of the silica sand. We show that the experimental and calculated trends are similar and they both depend on the electric power level and the silica sand mean granulometry. The maximum pressures are observed at the same time as the maximum electric power levels. The ratio P{sub SAND}/P{sub GAS} is about 8 with P{sub GAS} values not exceeding 1.5 x 10{sup 5} Pa.

  1. Demonstrating Earth connections and fuses working together

    Science.gov (United States)

    Harrison, Mark

    2017-03-01

    Earth wires and fuses work together in UK mains circuits to keep users safe from electric shocks and are taught in many school contexts. The subject can be quite abstract and difficult for pupils to grasp, and a simple but visually clear and direct demonstration is described which would be easy for most physics departments to build and which can make the concepts much more immediately understandable.

  2. The Anti-Cancer Potency and Mechanism of a Novel Tumor-Activated Fused Toxin, DLM

    Directory of Open Access Journals (Sweden)

    Dejun Sun

    2015-02-01

    Full Text Available Melittin, which acts as a membrane-disrupting lytic peptide, is not only cytotoxic to tumors, but also vital to normal cells. Melittin had low toxicity when coupled with target peptides. Despite significant research development with the fused toxin, a new fused toxin is needed which has a cleavable linker such that the fused toxin can release melittin after protease cleavage on the tumor cell surface. We describe a novel fused toxin, composed of disintegrin, uPA (urokinase-type plasminogen activator-cleavable linker, and melittin. Disintegrin is a single strand peptide (73 aa isolated from Gloydius Ussuriensis venom. The RGD (Arg-Gly-Asp site of disintegrin dominates its interaction with integrins on the surface of the tumor cells. uPA is over-expressed and plays an important role in tumor cell invasiveness and metastatic progression. The DLM (disintegrin-linker-melittin linker is uPA-cleavable, enabling DLM to release melittin. We compared binding activity of our synthesized disintegrin with native disintegrin and report that DLM had less binding activity than the native form. uPA-cleavage was evaluated in vitro and the uPA-cleavable linker released melittin. Treating tumors expressing uPA with DLM enhanced tumor cell killing as well as reduced toxicity to erythrocytes and other non-cancerous normal cells. The mechanism behind DLM tumor cell killing was tested using a DNA ladder assay, fluorescent microscopy, flow cytometry, and transmission electron microscopy. Data revealed tumor cell necrosis as the mechanism of cell death, and the fused DLM toxin with an uPA-cleavable linker enhanced tumor selectivity and killing ability.

  3. Testosterone inhibits transforming growth factor-β signaling during myogenic differentiation and proliferation of mouse satellite cells: potential role of follistatin in mediating testosterone action.

    Science.gov (United States)

    Braga, Melissa; Bhasin, Shalender; Jasuja, Ravi; Pervin, Shehla; Singh, Rajan

    2012-03-05

    Testosterone (T) administration is associated with increased satellite cell number and skeletal muscle hypertrophy, although there is considerable heterogeneity in the response of different skeletal muscle groups to T in vivo. We investigated the effects of T on the growth and differentiation of satellite cells isolated from levator ani (LA) and gastrocnemius (gastroc) muscles. T up regulated follistatin (Fst) expression, but down regulated the mRNA and protein expression of a number of genes in the transforming growth factor-beta (TGF-β)-signaling pathway. Inhibition of Fst expression by small interfering RNA (siRNA) inhibited myogenic differentiation and blocked the pro-myogenic effects of T. Treatment of satellite cells with T or Fst up regulated the expression of Pax7 and PCNA, and increased their proliferation. T and Fst blocked TGF-β induced inhibition of growth and myogenic differentiation and down regulated TGF-β-dependent transcriptome in both LA and gastroc cells. We conclude that T stimulation of satellite cell proliferation and myogenic differentiation are associated with up regulation of Fst and inhibition of TGF-β-signaling.

  4. Far Ultraviolet Spectroscopic Explorer(FUSE) Observations Of The Antennae Galaxies (ngc4038/ngc4039)

    Science.gov (United States)

    Iping, Rosina; Sonneborn, G.; Neff, S.

    2006-06-01

    The brightest UV region of the Antennae galaxies (NGC4038/4039), Knots R/S/T, has been observed with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite. The observation used a 30x30 arcsec aperture, encompassing several stellar groups. The high-resolution FUV spectrum detects broad ( 150 km/s FWHM) O VI 1032, 1038 absorption blueward of the systemic velocity (1642 km/s) in the galactic outflow. This outflowing gas has a temperature of a few times 105 K and may dominate the radiative cooling of the supernova-heated interstellar medium. Strong C II 1036, H I 1026, S III 1012, 1015, S IV 1062, 1072 and Si IV 1122, 1128 have symmetric absorption features centered at the systemic velocity. These features probably originate from the OB stellar population in the galaxies. This work has been supported in part by a FUSE Guest Investigator grant from NASA (NAG5-13014) to the Catholic University of America.

  5. Modelling and Analysis of Proximity Effect in IGBT Fuses

    DEFF Research Database (Denmark)

    Iov, Florin; Blaabjerg, Frede; Rasmussen, Henrik

    2005-01-01

    . Even with an active protection, a high power IGBT still has a risk of exhibiting a violent rupture in the case of a fault if e.g. IGBT fuses are not protecting it. By introducing fuses into voltage source converters a better protection of IGBT's can be achieved. However, skin and proximity effects...... affect the current distribution in a fuse due to the high frequency currents and thus a need for de-rating the fuse. This paper shows an analytical model for studying the proximity effect into a fuse. The results obtained using this model are compared with experiments....

  6. Induction of MTG8-specific cytotoxic T-cell lines: MTG8 is probably a tumour antigen that is recognized by cytotoxic T cells in AML1-MTG8-fused gene-positive acute myelogenous leukaemia.

    Science.gov (United States)

    Maeda, M; Otsuka, T; Kimura, N; Kozu, T; Fukuyama, T; Uchida, N; Sugio, Y; Itoh, Y; Iino, T; Inaba, S; Niho, Y

    2000-11-01

    Several reports have demonstrated the persistent detection of AML1-MTG8 fusion products, representing minimal residual disease (MRD), in patients with t(8;21) acute myelogenous leukaemia (AML) who are in long-term remission. It is probable that immune-mediated mechanisms that are able to suppress the expansion of MRD may result in the continuance of remission. It was previously shown that some t(8;21) AML patients had high anti-MTG8 antibody titres. MTG8 expression in normal adult tissues is limited to the brain or heart in which human leucocyte antigen (HLA) class I cell-surface antigens are either not or are only faintly detectable. We hypothesized that the overexpression of the MTG8 gene in t(8;21) AML cells could act as a possible tumour antigen, which might be able to induce the immune-mediated suppression of the expansion of MRD. We were able to induce HLA-A0201-restricted cytotoxic T-lymphocyte (CTL) lines against an MTG8 peptide (MTG8b amino acids 182-191) using monocyte-derived dendritic cells from a healthy donor. T-cell receptor (TCR)Valpha17, TCRVbeta14 and 15, and TCRJbeta2.1 and 2.3 are predominantly used in these CTL lines. Our data, which suggest that the MTG8 protein could be one of the tumour antigens recognized by CTLs, may be helpful in further investigations of TCR analysis in t(8;21) AML patients with HLA-A0201 who are in long-term remission.

  7. The Spindle Assembly Checkpoint Safeguards Genomic Integrity of Skeletal Muscle Satellite Cells

    Directory of Open Access Journals (Sweden)

    Swapna Kollu

    2015-06-01

    Full Text Available To ensure accurate genomic segregation, cells evolved the spindle assembly checkpoint (SAC, whose role in adult stem cells remains unknown. Inducible perturbation of a SAC kinase, Mps1, and its downstream effector, Mad2, in skeletal muscle stem cells shows the SAC to be critical for normal muscle growth, repair, and self-renewal of the stem cell pool. SAC-deficient muscle stem cells arrest in G1 phase of the cell cycle with elevated aneuploidy, resisting differentiation even under inductive conditions. p21CIP1 is responsible for these SAC-deficient phenotypes. Despite aneuploidy’s correlation with aging, we find that aged proliferating muscle stem cells display robust SAC activity without elevated aneuploidy. Thus, muscle stem cells have a two-step mechanism to safeguard their genomic integrity. The SAC prevents chromosome missegregation and, if it fails, p21CIP1-dependent G1 arrest limits cellular propagation and tissue integration. These mechanisms ensure that muscle stem cells with compromised genomes do not contribute to tissue homeostasis.

  8. VL51ES (Generation 6 Li-Ion Cell for Satellites

    Directory of Open Access Journals (Sweden)

    Defer M.

    2017-01-01

    Full Text Available This paper presents the design of Saft’s VL51ES (Generation 6 Li-Ion cell, the main challenges in the course of the development, the main BOL characteristics and performances achieved during the development program. Finally, it also describes how this cell fits in Saft’s battery range and the benefits of it.

  9. Land Cover Classification Based on Fused Data from GF-1 and MODIS NDVI Time Series

    Directory of Open Access Journals (Sweden)

    Fanjie Kong

    2016-09-01

    Full Text Available Accurate regional and global information on land cover and its changes over time is crucial for environmental monitoring, land management, and planning. In this study, we selected Fengning County, in China’s Hebei Province, as a case study area. Using satellite data, we generated fused normalized-difference vegetation index (NDVI data with high spatial and temporal resolution by utilizing the STARFM algorithm to produce a fused GF-1 and MODIS NDVI dataset. We extracted seven phenological parameters (including the start, end, and length of the growing season, base value, mid-season date, maximum NDVI, seasonal NDVI amplitude from a fused NDVI time-series after reconstruction using the TIMESAT software. We developed four classification scenarios based on different combinations of GF-1 spectral features, the fused NDVI time-series, and the phenological parameters. We then classified the land cover using a support vector machine and analyzed the classification accuracies. We found that the proposed method achieved satisfactory classification results, and that the combination of the fused NDVI data with the extracted phenological parameters significantly improved classification accuracy. The classification accuracy based on the composited GF-1 multi-spectral bands combined with the phenological parameters was the highest among the four scenarios, with an overall classification accuracy of 88.8% and a Kappa coefficient of 0.8714, which represent increases of 9.3 percentage points and 0.1073, respectively, compared with GF-1 spectral data alone. The producer’s and user’s accuracy for different land cover types improved, with a few exceptions, and cropland and broadleaf forest had the largest increase.

  10. MicroRNA-1 and MicroRNA-206 Improve Differentiation Potential of Human Satellite Cells : A Novel Approach for Tissue Engineering of Skeletal Muscle

    NARCIS (Netherlands)

    Koning, Merel; Werker, Paul M. N.; van der Schaft, Daisy W. J.; Bank, Ruud A.; Harmsen, Martin C.

    2012-01-01

    Innovative strategies based on regenerative medicine, in particular tissue engineering of skeletal muscle, are promising for treatment of patients with skeletal muscle damage. However, the efficiency of satellite cell differentiation in vitro is suboptimal. MicroRNAs are involved in the regulation o

  11. Satellite RNAs and Satellite Viruses.

    Science.gov (United States)

    Palukaitis, Peter

    2016-03-01

    Satellite RNAs and satellite viruses are extraviral components that can affect either the pathogenicity, the accumulation, or both of their associated viruses while themselves being dependent on the associated viruses as helper viruses for their infection. Most of these satellite RNAs are noncoding RNAs, and in many cases, have been shown to alter the interaction of their helper viruses with their hosts. In only a few cases have the functions of these satellite RNAs in such interactions been studied in detail. In particular, work on the satellite RNAs of Cucumber mosaic virus and Turnip crinkle virus have provided novel insights into RNAs functioning as noncoding RNAs. These effects are described and potential roles for satellite RNAs in the processes involved in symptom intensification or attenuation are discussed. In most cases, models describing these roles involve some aspect of RNA silencing or its suppression, either directly or indirectly involving the particular satellite RNA.

  12. Standardizing Quality Assessment of Fused Remotely Sensed Images

    Science.gov (United States)

    Pohl, C.; Moellmann, J.; Fries, K.

    2017-09-01

    The multitude of available operational remote sensing satellites led to the development of many image fusion techniques to provide high spatial, spectral and temporal resolution images. The comparison of different techniques is necessary to obtain an optimized image for the different applications of remote sensing. There are two approaches in assessing image quality: 1. Quantitatively by visual interpretation and 2. Quantitatively using image quality indices. However an objective comparison is difficult due to the fact that a visual assessment is always subject and a quantitative assessment is done by different criteria. Depending on the criteria and indices the result varies. Therefore it is necessary to standardize both processes (qualitative and quantitative assessment) in order to allow an objective image fusion quality evaluation. Various studies have been conducted at the University of Osnabrueck (UOS) to establish a standardized process to objectively compare fused image quality. First established image fusion quality assessment protocols, i.e. Quality with No Reference (QNR) and Khan's protocol, were compared on varies fusion experiments. Second the process of visual quality assessment was structured and standardized with the aim to provide an evaluation protocol. This manuscript reports on the results of the comparison and provides recommendations for future research.

  13. Quartz/fused silica chip carriers

    Science.gov (United States)

    1992-01-01

    The primary objective of this research and development effort was to develop monolithic microwave integrated circuit (MMIC) packaging which will operate efficiently at millimeter-wave frequencies. The packages incorporated fused silica as the substrate material which was selected due to its favorable electrical properties and potential performance improvement over more conventional materials for Ka-band operation. The first step towards meeting this objective is to develop a package that meets standard mechanical and thermal requirements using fused silica and to be compatible with semiconductor devices operating up to at least 44 GHz. The second step is to modify the package design and add multilayer and multicavity capacity to allow for application specific integrated circuits (ASIC's) to control multiple phase shifters. The final step is to adapt the package design to a phased array module with integral radiating elements. The first task was a continuation of the SBIR Phase 1 work. Phase 1 identified fused silica as a viable substrate material by demonstrating various plating, machining, and adhesion properties. In Phase 2 Task 1, a package was designed and fabricated to validate these findings. Task 2 was to take the next step in packaging and fabricate a multilayer, multichip module (MCM). This package is the predecessor to the phased array module and demonstrates the ability to via fill, circuit print, laminate, and to form vertical interconnects. The final task was to build a phased array module. The radiating elements were to be incorporated into the package instead of connecting to it with wire or ribbon bonds.

  14. Medicinal Chemistry Perspective of Fused Isoxazole Derivatives.

    Science.gov (United States)

    Barmade, Mahesh A; Murumkar, Prashant R; Sharma, Mayank Kumar; Yadav, Mange Ram

    2016-01-01

    Nitrogen containing heterocyclic rings with an oxygen atom is considered as one of the best combination in medicinal chemistry due to their diversified biological activities. Isoxazole, a five membered heterocyclic azole ring is found in naturally occuring ibetonic acid along with some of the marketed drugs such as valdecoxib, flucloxacillin, cloxacillin, dicloxacillin, and danazol. It is also significant for showing antipsychotic activity in risperidone and anticonvulsant activity in zonisamide, the marketed drugs. This review article covers research articles reported till date covering biological activity along with SAR of fused isoxazole derivatives.

  15. Semiautomatic MDF deburring tool. [Mild detonating fuse

    Energy Technology Data Exchange (ETDEWEB)

    Simonton, W.L.

    1976-03-31

    A device for semiautomatically deburring the ends of lengths of MDF (mild detonating fuse) was developed by the Automation Development group at Mound Laboratory. The device performs the deburring function by cutting a 0.002 in. x 0.002 in. chamfer on the MDF with small rotating blades. This air-operated, semiautomatic device provides improvement over the manual method of removing burrs by reduction in time and operator strain. A time study is underway to determine the time saved which is expected to be about 75 percent.

  16. Satellite Cell Functional Alterations Following Cutaneous Burn in rats Include an Increase in Their Osteogenic Potential

    Science.gov (United States)

    2013-10-07

    skeletal muscle hypertrophy and atrophy. Nat Cell Biol 2003;5:87. [6] Brack AS, Rando TA. Intrinsic changes and extrinsic influences of myogenic stem...Skeletal muscle Muscle precursor cell Thermal injury Atrophy Heterotopic ossification a b s t r a c t Background: Significant consequences of severe burn...include skeletal muscle atrophy and heterotopic ossification (HO). The cellular mechanisms underlying either of these condi- tions are not known

  17. Centriolar satellites

    DEFF Research Database (Denmark)

    Tollenaere, Maxim A X; Mailand, Niels; Bekker-Jensen, Simon

    2015-01-01

    Centriolar satellites are small, microscopically visible granules that cluster around centrosomes. These structures, which contain numerous proteins directly involved in centrosome maintenance, ciliogenesis, and neurogenesis, have traditionally been viewed as vehicles for protein trafficking...... highlight newly discovered regulatory mechanisms targeting centriolar satellites and their functional status, and we discuss how defects in centriolar satellite components are intimately linked to a wide spectrum of human diseases....

  18. Expression, purification, and bioactivity of GST-fused v-Src from a bacterial expression system

    Institute of Scientific and Technical Information of China (English)

    GONG Xing-guo; JI Jing; XIE Jie; ZHOU Yuan; ZHANG Jun-yan; ZHONG Wen-tao

    2006-01-01

    v-Src is a non-receptor protein tyrosine kinase involved in many signal transduction pathways and closely related to the activation and development of cancers. We present herethe expression, purification, and bioactivity of a GST (glutathione S-transferase)-fused v-Src from a bacterial expression system. Different culture conditions were examined in an isopropyl β-D-thiogalactopyranoside (IPTG)-regulated expression, and the fused protein was purified using GSH (glutathione) affinity chromatography. ELISA (enzyme-linked immunosorbent assay) was employed to determine the phosphorylation kinase activity of the GST-fused v-Src. This strategy seems to be more promising than the insect cell system or other eukaryotic systems employed in earlier Src expression.

  19. In situ hybridization of the feline major satellite DNA FA-SAT in feline fibrosarcoma cell lines and feline fibrosarcoma tissue sections

    OpenAIRE

    Alfaro Alarcón, Alejandro

    2009-01-01

    Feline fibrosarcomas are the most common skin tumors of cats. Despite this high frequency and the publication of different hypotheses for their pathogenesis by several authors, the alterations accompanying the development of this tumor are still not completely understood. We studied the feline major satellite DNA (FA-SAT) hybridization pattern by FISH in four fibrosarcoma cell lines and one normal embryonic fibroblastic cell line as well as in 30 fibrosarcomas from 28 cats. Of the latter, ...

  20. Satellite theory

    Science.gov (United States)

    Kozai, Y.

    1981-04-01

    The dynamical characteristics of the natural satellite of Mars, Jupiter, Saturn, Uranus and Neptune are analyzed on the basis of the solar tidal perturbation factor and the oblateness factor of the primary planet for each satellite. For the inner satellites, for which the value of the solar tidal factor is much smaller than the planetary oblateness factor, it is shown that the eccentricity and inclination of satellite orbits are generally very small and almost constant; several pairs of inner satellites are also found to exhibit commensurable mean motions, or secular accelerations in mean longitude. In the case of the outer satellites, for which solar perturbations are dominant, secular perturbations and long-period perturbations may be derived by the solution of equations of motion reduced to one degree of freedom. The existence of a few satellites, termed intermediary satellites, for which the solar tidal perturbation is on the order of the planetary oblateness factor, is also observed, and the pole of the orbital plane of the satellite is noted to execute a complex motion around the pole of the planet or the orbital plane of the planet.

  1. Sphingosine-1-phosphate enhances satellite cell activation in dystrophic muscles through a S1PR2/STAT3 signaling pathway.

    Directory of Open Access Journals (Sweden)

    Kenneth C Loh

    Full Text Available Sphingosine-1-phosphate (S1P activates a widely expressed family of G protein-coupled receptors, serves as a muscle trophic factor and activates muscle stem cells called satellite cells (SCs through unknown mechanisms. Here we show that muscle injury induces dynamic changes in S1P signaling and metabolism in vivo. These changes include early and profound induction of the gene encoding the S1P biosynthetic enzyme SphK1, followed by induction of the catabolic enzyme sphingosine phosphate lyase (SPL 3 days later. These changes correlate with a transient increase in circulating S1P levels after muscle injury. We show a specific requirement for SphK1 to support efficient muscle regeneration and SC proliferation and differentiation. Mdx mice, which serve as a model for muscular dystrophy (MD, were found to be S1P-deficient and exhibited muscle SPL upregulation, suggesting that S1P catabolism is enhanced in dystrophic muscle. Pharmacological SPL inhibition increased muscle S1P levels, improved mdx muscle regeneration and enhanced SC proliferation via S1P receptor 2 (S1PR2-dependent inhibition of Rac1, thereby activating Signal Transducer and Activator of Transcription 3 (STAT3, a central player in inflammatory signaling. STAT3 activation resulted in p21 and p27 downregulation in a S1PR2-dependent fashion in myoblasts. Our findings suggest that S1P promotes SC progression through the cell cycle by repression of cell cycle inhibitors via S1PR2/STAT3-dependent signaling and that SPL inhibition may provide a therapeutic strategy for MD.

  2. Community effect triggers terminal differentiation of myogenic cells derived from muscle satellite cells by quenching Smad signaling

    Energy Technology Data Exchange (ETDEWEB)

    Yanagisawa, Michiko [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan); Aging Research, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Aichi 466-8550 (Japan); Mukai, Atsushi; Shiomi, Kosuke [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan); Song, Si-Yong [Institute of Neuroscience, Faculty of Pharmaceutical Sciences at Kagawa, Tokushima Bunri University, 1314-1 Shido, Sanuki-shi, Kagawa 769-2193 (Japan); Hashimoto, Naohiro, E-mail: nao@ncgg.go.jp [Department of Regenerative Medicine, National Institute for Longevity Sciences, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Oobu, Aichi 474-8522 (Japan)

    2011-01-15

    A high concentration of bone morphogenetic proteins (BMPs) stimulates myogenic progenitor cells to undergo heterotopic osteogenic differentiation. However, the physiological role of the Smad signaling pathway during terminal muscle differentiation has not been resolved. We report here that Smad1/5/8 was phosphorylated and activated in undifferentiated growing mouse myogenic progenitor Ric10 cells without exposure to any exogenous BMPs. The amount of phosphorylated Smad1/5/8 was severely reduced during precocious myogenic differentiation under the high cell density culture condition even in growth medium supplemented with a high concentration of serum. Inhibition of the Smad signaling pathway by dorsomorphin, an inhibitor of Smad activation, or noggin, a specific antagonist of BMP, induced precocious terminal differentiation of myogenic progenitor cells in a cell density-dependent fashion even in growth medium. In addition, Smad1/5/8 was transiently activated in proliferating myogenic progenitor cells during muscle regeneration in rats. The present results indicate that the Smad signaling pathway is involved in a critical switch between growth and differentiation of myogenic progenitor cells both in vitro and in vivo. Furthermore, precocious cell density-dependent myogenic differentiation suggests that a community effect triggers the terminal muscle differentiation of myogenic cells by quenching the Smad signaling.

  3. Electrostatic Discharge Properties of Fused Silica Coatings

    Science.gov (United States)

    Andersen, Allen; Sim, Charles; Dennison, J. R.

    2012-10-01

    The electric field value at which electrostatic discharge (ESD) occurs was studied for thin coatings of fused silica (highly disordered SiO2/SiOx) on conductive substrates, such as those encountered as optical coatings and in Si microfabrication. The electrostatic breakdown field was determined using an increasing voltage, while monitoring the leakage current. A simple parallel-plate capacitor geometry was used, under medium vacuum and at temperatures down to ˜150 K using a liquid N2 reservoir. The breakdown field, pre-breakdown arcing and I-V curves for fused silica samples are compared for ˜60 nm and ˜80 μm thick, room and low temperature, and untreated and irradiated samples. Unlike typical I-V results for polymeric insulators, the thin film silica samples did not exhibit pre-breakdown arcing, displayed transitional resistivity after initial breakdown, and in many cases showed evidence of a second discontinuity in the I-V curves. This diversity of observed discharge phenomena is discussed in terms of breakdown modes and defect generation on a microscopic scale.

  4. Automated Target Planning for FUSE Using the SOVA Algorithm

    Science.gov (United States)

    Heatwole, Scott; Lanzi, R. James; Civeit, Thomas; Calvani, Humberto; Kruk, Jeffrey W.; Suchkov, Anatoly

    2007-01-01

    The SOVA algorithm was originally developed under the Resilient Systems and Operations Project of the Engineering for Complex Systems Program from NASA s Aerospace Technology Enterprise as a conceptual framework to support real-time autonomous system mission and contingency management. The algorithm and its software implementation were formulated for generic application to autonomous flight vehicle systems, and its efficacy was demonstrated by simulation within the problem domain of Unmanned Aerial Vehicle autonomous flight management. The approach itself is based upon the precept that autonomous decision making for a very complex system can be made tractable by distillation of the system state to a manageable set of strategic objectives (e.g. maintain power margin, maintain mission timeline, and et cetera), which if attended to, will result in a favorable outcome. From any given starting point, the attainability of the end-states resulting from a set of candidate decisions is assessed by propagating a system model forward in time while qualitatively mapping simulated states into margins on strategic objectives using fuzzy inference systems. The expected return value of each candidate decision is evaluated as the product of the assigned value of the end-state with the assessed attainability of the end-state. The candidate decision yielding the highest expected return value is selected for implementation; thus, the approach provides a software framework for intelligent autonomous risk management. The name adopted for the technique incorporates its essential elements: Strategic Objective Valuation and Attainability (SOVA). Maximum value of the approach is realized for systems where human intervention is unavailable in the timeframe within which critical control decisions must be made. The Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, launched in 1999, has been collecting science data for eight years.[1] At its beginning of life, FUSE had six gyros in two

  5. Temporal changes in glycogenolytic enzyme mRNAs during myogenesis of primary porcine satellite cells

    DEFF Research Database (Denmark)

    Henckel, Poul; Theil, Peter Kappel; Sørensen, Inge Lise

    2007-01-01

    , phosphorylase kinase, phosphorylase and glycogen debranching enzyme, and no alterations of the transporter molecule GLUT4, clearly indicate that glycogenolytic enzymes of potential importance to meat quality development are regulated at the gene level during myogenesis, and are heavily involved in muscle cell...... and muscle fibre development. The genes, however, are not influenced by insulin, and the lack of response to insulin of expression of gene-encoding enzymes involved in the formation and degradation of glycogen may question the applicability of porcine cell culture systems, like the one applied, as a model...

  6. Extracellular Vesicles: Satellites of Information Transfer in Cancer and Stem Cell Biology.

    Science.gov (United States)

    Desrochers, Laura M; Antonyak, Marc A; Cerione, Richard A

    2016-05-23

    The generation and shedding of extracellular vesicles (EVs), including exosomes and microvesicles (MVs), by cells has emerged as a form of intercellular communication with important roles in several physiological processes and diseases such as cancer. These membrane-enclosed packets can transfer specific proteins, RNA transcripts, microRNAs, and even DNA to target cells, thereby altering their function. Despite the exponential growth of the EV field, a great deal remains unclear about the mechanisms that regulate exosome and MV biogenesis, as well as about how to isolate different classes of EVs and how to best take advantage of them for clinical applications.

  7. Identification of genes differentially expressed in myogenin knock-down bovine muscle satellite cells during differentiation through RNA sequencing analysis.

    Directory of Open Access Journals (Sweden)

    Eun Ju Lee

    Full Text Available BACKGROUND: The expression of myogenic regulatory factors (MRFs consisting of MyoD, Myf5, myogenin (MyoG and MRF4 characterizes various phases of skeletal muscle development including myoblast proliferation, cell-cycle exit, cell fusion and the maturation of myotubes to form myofibers. Although it is well known that the function of MyoG cannot be compensated for other MRFs, the molecular mechanism by which MyoG controls muscle cell differentiation is still unclear. Therefore, in this study, RNA-Seq technology was applied to profile changes in gene expression in response to MyoG knock-down (MyoGkd in primary bovine muscle satellite cells (MSCs. RESULTS: About 61-64% of the reads of over 42 million total reads were mapped to more than 13,000 genes in the reference bovine genome. RNA-Seq analysis identified 8,469 unique genes that were differentially expressed in MyoGkd. Among these genes, 230 were up-regulated and 224 were down-regulated by at least four-fold. DAVID Functional Annotation Cluster (FAC and pathway analysis of all up- and down-regulated genes identified overrepresentation for cell cycle and division, DNA replication, mitosis, organelle lumen, nucleoplasm and cytosol, phosphate metabolic process, phosphoprotein phosphatase activity, cytoskeleton and cell morphogenesis, signifying the functional implication of these processes and pathways during skeletal muscle development. The RNA-Seq data was validated by real time RT-PCR analysis for eight out of ten genes as well as five marker genes investigated. CONCLUSIONS: This study is the first RNA-Seq based gene expression analysis of MyoGkd undertaken in primary bovine MSCs. Computational analysis of the differentially expressed genes has identified the significance of genes such as SAP30-like (SAP30L, Protein lyl-1 (LYL1, various matrix metalloproteinases, and several glycogenes in myogenesis. The results of the present study widen our knowledge of the molecular basis of skeletal muscle

  8. Impaired metabolism of senescent muscle satellite cells is associated with oxidative modifications of glycolytic enzymes

    DEFF Research Database (Denmark)

    Baraibar, Martin; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina;

    2014-01-01

    leading to increased mobilization of non-carbohydrate substrates as branched chain amino acids or long chain fatty acids was observed in senescent cells. In addition, phospho-and glycerolipids metabolism was altered. Increased levels of acyl-carnitines indicated augmented turnover of storage and membrane...

  9. Split Bregman method for large scale fused Lasso

    CERN Document Server

    Ye, Gui-Bo

    2010-01-01

    rdering of regression or classification coefficients occurs in many real-world applications. Fused Lasso exploits this ordering by explicitly regularizing the differences between neighboring coefficients through an $\\ell_1$ norm regularizer. However, due to nonseparability and nonsmoothness of the regularization term, solving the fused Lasso problem is computationally demanding. Existing solvers can only deal with problems of small or medium size, or a special case of the fused Lasso problem in which the predictor matrix is identity matrix. In this paper, we propose an iterative algorithm based on split Bregman method to solve a class of large-scale fused Lasso problems, including a generalized fused Lasso and a fused Lasso support vector classifier. We derive our algorithm using augmented Lagrangian method and prove its convergence properties. The performance of our method is tested on both artificial data and real-world applications including proteomic data from mass spectrometry and genomic data from array...

  10. Improved image classification with neural networks by fusing multispectral signatures with topological data

    Science.gov (United States)

    Harston, Craig; Schumacher, Chris

    1992-01-01

    Automated schemes are needed to classify multispectral remotely sensed data. Human intelligence is often required to correctly interpret images from satellites and aircraft. Humans suceed because they use various types of cues about a scene to accurately define the contents of the image. Consequently, it follows that computer techniques that integrate and use different types of information would perform better than single source approaches. This research illustrated that multispectral signatures and topographical information could be used in concert. Significantly, this dual source tactic classified a remotely sensed image better than the multispectral classification alone. These classifications were accomplished by fusing spectral signatures with topographical information using neural network technology. A neural network was trained to classify Landsat mulitspectral signatures. A file of georeferenced ground truth classifications were used as the training criterion. The network was trained to classify urban, agriculture, range, and forest with an accuracy of 65.7 percent. Another neural network was programmed and trained to fuse these multispectral signature results with a file of georeferenced altitude data. This topological file contained 10 levels of elevations. When this nonspectral elevation information was fused with the spectral signatures, the classifications were improved to 73.7 and 75.7 percent.

  11. Understanding error generation in fused deposition modeling

    Science.gov (United States)

    Bochmann, Lennart; Bayley, Cindy; Helu, Moneer; Transchel, Robert; Wegener, Konrad; Dornfeld, David

    2015-03-01

    Additive manufacturing offers completely new possibilities for the manufacturing of parts. The advantages of flexibility and convenience of additive manufacturing have had a significant impact on many industries, and optimizing part quality is crucial for expanding its utilization. This research aims to determine the sources of imprecision in fused deposition modeling (FDM). Process errors in terms of surface quality, accuracy and precision are identified and quantified, and an error-budget approach is used to characterize errors of the machine tool. It was determined that accuracy and precision in the y direction (0.08-0.30 mm) are generally greater than in the x direction (0.12-0.62 mm) and the z direction (0.21-0.57 mm). Furthermore, accuracy and precision tend to decrease at increasing axis positions. The results of this work can be used to identify possible process improvements in the design and control of FDM technology.

  12. Laser Damage Precursors in Fused Silica

    Energy Technology Data Exchange (ETDEWEB)

    Miller, P; Suratwala, T; Bude, J; Laurence, T A; Shen, N; Steele, W A; Feit, M; Menapace, J; Wong, L

    2009-11-11

    There is a longstanding, and largely unexplained, correlation between the laser damage susceptibility of optical components and both the surface quality of the optics, and the presence of near surface fractures in an optic. In the present work, a combination of acid leaching, acid etching, and confocal time resolved photoluminescence (CTP) microscopy has been used to study laser damage initiation at indentation sites. The combination of localized polishing and variations in indentation loads allows one to isolate and characterize the laser damage susceptibility of densified, plastically flowed and fractured fused silica. The present results suggest that: (1) laser damage initiation and growth are strongly correlated with fracture surfaces, while densified and plastically flowed material is relatively benign, and (2) fracture events result in the formation of an electronically defective rich surface layer which promotes energy transfer from the optical beam to the glass matrix.

  13. Mid-IR fused fiber couplers

    Science.gov (United States)

    Stevens, G.; Woodbridge, T.

    2016-03-01

    We present results from our recent efforts on developing single-mode fused couplers in ZBLAN fibre. We have developed a custom fusion workstation for working with lower melting temperature fibres, such as ZBLAN and chalcogenide fibres. Our workstation uses a precisely controlled electrical heater designed to operate at temperatures between 100 - 250°C as our heat source. The heated region of the fibers was also placed in an inert atmosphere to avoid the formation of microcrystal inclusions during fusion. We firstly developed a process for pulling adiabatic tapers in 6/125 μm ZBLAN fibre. The tapers were measured actively during manufacture using a 2000 nm source. The process was automated so that the heater temperature and motor speed automatically adjusted to pull the taper at constant tension. This process was then further developed so that we could fuse and draw two parallel 6/125 μm ZBLAN fibres, forming a single-mode coupler. Low ratio couplers (1-10%) that could be used as power monitors were manufactured that had an excess loss of 0.76 dB. We have also manufactured 50/50 splitters and wavelength division multiplexers (WDMs). However, the excess loss of these devices was typically 2 - 3 dB. The increased losses were due to localised necking and surface defects forming as the tapers were pulled further to achieve a greater coupling ratio. Initial experiments with chalcogenide fibre have shown that our process can be readily adapted for chalcogenide fibres. A 5% coupler with 1.5 dB insertion loss was manufactured using commercial of the shelf (COTS) fibres.

  14. High Voltage Applications of Explosively Formed Fuses

    Science.gov (United States)

    Tasker, D. G.; Goforth, J. H.; Fowler, C. M.; Herrera, D. H.; King, J. C.; Lopez, E. A.; Martinez, E. C.; Oona, H.; Marsh, S. P.; Reinovsky, R. E.; Stokes, J.; Tabaka, L. J.; Torres, D. T.; Sena, F. C.; Kiuttu, G.; Degnan, J.

    2004-11-01

    At Los Alamos, we have primarily applied Explosively Formed Fuse (EFF) techniques to high current systems. In these systems, the EFF has interrupted currents from 19-25 MA, thus diverting the current to low inductance loads. The transferred current magnitude is determined by the ratio of storage inductance to load inductance and, with dynamic loads, the current has ranged from 12-20 MA. In a system with 18 MJ stored energy, the switch operates at a power of up to 6 TW. We are now investigating the use of the EFF technique to apply high voltages to high impedance loads in systems that are more compact. In these systems we are exploring circuits with EFF lengths from 43-100 cm, which have storage inductances large enough to apply 300-500 kV across high impedance loads. Experimental results and design considerations are presented. Using cylindrical EFF switches of 10 cm diameter and 43 cm length, currents of approximately 3 MA were interrupted producing ~200 kV. This indicates the switch had an effective resistance of ~100 mΩ where 150-200 mΩ was expected. To understand the lower performance, several parameters were studied including electrical conduction through the explosive products; current density; explosive initiation; insulator type and conductor thickness. The results show a number of interesting features, most notably that the primary mechanism of switch operation is mechanical and not electrical fusing of the conductor. Switches opening on a 1-10 μs time scale with resistances starting at 50 μΩ and increasing to perhaps 1 Ω now seem possible to construct using explosive charges as small as a few pounds.

  15. Injection of duck recombinant follistatin fusion protein into duck muscle tissues stimulates satellite cell proliferation and muscle fiber hypertrophy.

    Science.gov (United States)

    Liu, He-he; Wang, Ji-wen; Yu, Hai-yue; Zhang, Rong-ping; Chen, Xi; Jin, Hai-bo; Dai, Fei; Li, Liang; Xu, Feng

    2012-06-01

    Follistatin (FST) can inhibit the expression of myostatin, which is a predominant inhibitor of muscle development. The potential application of myostatin-based technology has been prompted in different ways in agriculture. We previously constructed an expression vector of duck FST and isolated the FST fusion protein. After the protein was purified and refolded, it was added to the medium of duck myoblasts cultured in vitro. The results show that the 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide value of the myoblasts in the duck FST treatment group is higher than that in the control group, which indicates that the duck FST fusion protein exhibits the biological activities that can accelerate myoblast proliferation. To further investigate the roles of duck FST on muscle development, we injected the protein into the duck muscle tissues in vivo. The results show that both the duck muscle fiber cross-sectional area and the satellite cell activation frequency are influenced more in the FST treatment group than they are in the control group. In addition to these phenomena, expression of MyoD and Myf5 were increased, and the expression of myostatin was decreased. Together, these results suggest the potential for using duck FST fusion protein to inhibit myostatin activity and subsequently to enhance muscle growth in vivo. The mechanism by which FST regulates muscle development in the duck is similar to that in mammals and fishes.

  16. Effects of Dexamethasone on Satellite Cells and Tissue Engineered Skeletal Muscle Units.

    Science.gov (United States)

    Syverud, Brian C; VanDusen, Keith W; Larkin, Lisa M

    2016-03-01

    Tissue engineered skeletal muscle has potential for application as a graft source for repairing soft tissue injuries, a model for testing pharmaceuticals, and a biomechanical actuator system for soft robots. However, engineered muscle to date has not produced forces comparable to native muscle, limiting its potential for repair and for use as an in vitro model for pharmaceutical testing. In this study, we examined the trophic effects of dexamethasone (DEX), a glucocorticoid that stimulates myoblast differentiation and fusion into myotubes, on our tissue engineered three-dimensional skeletal muscle units (SMUs). Using our established SMU fabrication protocol, muscle isolates were cultured with three experimental DEX concentrations (5, 10, and 25 nM) and compared to untreated controls. Following seeding onto a laminin-coated Sylgard substrate, the administration of DEX was initiated on day 0 or day 6 in growth medium or on day 9 after the switch to differentiation medium and was sustained until the completion of SMU fabrication. During this process, total cell proliferation was measured with a BrdU assay, and myogenesis and structural advancement of muscle cells were observed through immunostaining for MyoD, myogenin, desmin, and α-actinin. After SMU formation, isometric tetanic force production was measured to quantify function. The histological and functional assessment of the SMU showed that the administration of 10 nM DEX beginning on either day 0 or day 6 yielded optimal SMUs. These optimized SMUs exhibited formation of advanced sarcomeric structure and significant increases in myotube diameter and myotube fusion index, compared with untreated controls. Additionally, the optimized SMUs matured functionally, as indicated by a fivefold rise in force production. In conclusion, we have demonstrated that the addition of DEX to our process of engineering skeletal muscle tissue improves myogenesis, advances muscle structure, and increases force production in the

  17. Satellite Communications

    CERN Document Server

    Pelton, Joseph N

    2012-01-01

    The field of satellite communications represents the world's largest space industry. Those who are interested in space need to understand the fundamentals of satellite communications, its technology, operation, business, economic, and regulatory aspects. This book explains all this along with key insights into the field's future growth trends and current strategic challenges. Fundamentals of Satellite Communications is a concise book that gives all of the key facts and figures as well as a strategic view of where this dynamic industry is going. Author Joseph N. Pelton, PhD, former Dean of the International Space University and former Director of Strategic Policy at Intelstat, presents a r

  18. Relationship between skeletal muscle satellite cells and exercise%骨骼肌卫星细胞生长因子与运动训练的关系

    Institute of Scientific and Technical Information of China (English)

    谢永涛; 蓝岚

    2011-01-01

    BACKGROUND: High intensity of exercise can lead to injury to fine structure of skeletal muscle tissue, and the activation,proliferation and differentiation of skeletal muscle satellite cells are closely related to muscle tissue injury.OBJECTIVE: Based on the thinking that training can cause muscle structural damage and repair is needed, this study proposed a dependent relationship between repair of skeletal muscle structure and skeletal muscle satellite cells.METHODS: A computer-based retrieval was performed by the first author to search manuscripts in CNKI and Medline database published between 2000 and 2010 with the key words “skeletal muscle satellite cells, growth factor, exercise, and skeletal muscle ultrastructure” in English and Chinese languages. A total of 97 manuscripts were retrieved. Following inclusion and exclusion criteria, 23 manuscripts were included in the final analysis. The mechanism underlying skeletal tissue repair and skeletal muscle satellite cell activation was summarized, and the relationship between these two was analyzed.RESULTS AND CONCLUSION: High intensity of exercise can result in injury to skeletal muscle tissue, satellite cells are the key toskeletal muscle repair and the growth factors of satellite cells are also related to exercise methods. At present, the relationship between skeletal muscle satellite cells growth factors and exercise lacks of sufficient recognition and research.%背景:大运动量训练可以导致骨骼肌组织微细结构的损伤性变化,而骨骼肌卫星细胞的激活、增殖与分化和肌肉组织损伤的修复有密切关系.目的:文章从训练导致肌肉组织结构性损伤需要修复的客观实际出发,提出运动后骨骼肌结构的修复与骨骼肌卫星细胞生长因子之间存在某种依赖关系.方法:由第一作者通过计算机网络检索中国期刊全文数据库(CNKI)和Medline数据库(2000/2010),检索词分别为"骨骼肌卫星细胞,生长因子,运动训

  19. Satellite Geomagnetism

    DEFF Research Database (Denmark)

    Olsen, Nils; Stolle, Claudia

    2012-01-01

    Observations of Earth’s magnetic field from space began more than 50 years ago. A continuous monitoring of the field using low Earth orbit (LEO) satellites, however, started only in 1999, and three satellites have taken highprecision measurements of the geomagnetic field during the past decade...... ability to characterize and understand the many sources that contribute to Earth’s magnetic field. In this review, we summarize investigations of Earth’s interior and environment that have been possible through the analysis of high-precision magnetic field observations taken by LEO satellites........ The unprecedented time-space coverage of their data opened revolutionary new possibilities for monitoring, understanding, and exploring Earth’s magnetic field. In the near future, the three-satellite constellation Swarm will ensure continuity of such measurement and provide enhanced possibilities to improve our...

  20. Role of the mTORC1 Complex in Satellite Cell Activation by RNA-Induced Mitochondrial Restoration: Dual Control of Cyclin D1 through MicroRNAs

    OpenAIRE

    Jash, Sukanta; Dhar, Gunjan; Ghosh, Utpalendu; Adhya, Samit

    2014-01-01

    During myogenesis, satellite stem cells (SCs) are induced to proliferate and differentiate to myogenic precursors. The role of energy sensors such as the AMP-activated protein kinase (AMPK) and the mammalian Target of Rapamycin (mTOR) in SC activation is unclear. We previously observed that upregulation of ATP through RNA-mediated mitochondrial restoration (MR) accelerates SC activation following skeletal muscle injury. We show here that during regeneration, the AMPK-CRTC2-CREB and Raptor-mTO...

  1. Satellite (Natural)

    Science.gov (United States)

    Murdin, P.

    2000-11-01

    In its most general sense, any celestial object in orbit around a similar larger object. Thus, for example, the Magellanic Clouds are satellite galaxies of our own Milky Way galaxy. Without qualification, the term is used to mean a body in orbit around a planet; an alternative term is moon. The term natural satellite distinguishes these bodies from artificial satellites—spacecraft placed in orbi...

  2. FUSE observations of the central star of Abell 78

    CERN Document Server

    Werner, K; Koesterke, L; Kruk, J W

    2002-01-01

    FUSE high resolution spectra of two PG1159 type central stars (K1-16 and NGC 7094) have revealed an unexpected iron deficiency of at least 1 or 2 dex (Miksa et al. 2002). Here we present early results of FUSE spectroscopy of the CSPN Abell 78. It is shown that iron is strongly deficient in this star, too.

  3. Testosterone and trenbolone enanthate increase mature myostatin protein expression despite increasing skeletal muscle hypertrophy and satellite cell number in rodent muscle.

    Science.gov (United States)

    Dalbo, V J; Roberts, M D; Mobley, C B; Ballmann, C; Kephart, W C; Fox, C D; Santucci, V A; Conover, C F; Beggs, L A; Balaez, A; Hoerr, F J; Yarrow, J F; Borst, S E; Beck, D T

    2017-04-01

    The androgen-induced alterations in adult rodent skeletal muscle fibre cross-sectional area (fCSA), satellite cell content and myostatin (Mstn) were examined in 10-month-old Fisher 344 rats (n = 41) assigned to Sham surgery, orchiectomy (ORX), ORX + testosterone (TEST; 7.0 mg week(-1) ) or ORX + trenbolone (TREN; 1.0 mg week(-1) ). After 29 days, animals were euthanised and the levator ani/bulbocavernosus (LABC) muscle complex was harvested for analyses. LABC muscle fCSA was 102% and 94% higher in ORX + TEST and ORX + TREN compared to ORX (p TREN increased satellite cell numbers by 181% and 178% compared to ORX, respectively (p TREN compared to ORX (p TREN (p = .043), although there were no between-treatment effects regarding phosphorylated SMAD2/3. Mstn, ActrIIb and Mighty mRNAs were lower in ORX, ORX + TEST and ORX + TREN compared to SHAM (p < .05). Testosterone and trenbolone administration increased muscle fCSA and satellite cell number without increasing myonuclei number, and increased Mstn protein levels. Several genes and signalling proteins related to myostatin signalling were differentially regulated by ORX or androgen therapy.

  4. Thermal performance of back-up current-limiting fuses

    Energy Technology Data Exchange (ETDEWEB)

    Torres, E.; Mazon, A.J.; Fernandez, E.; Zamora, I. [Department of Electrical Engineering, University of the Basque Country (UPV/EHU), Alameda de Urquijo, s/n, Bilbao 48013, Bizkaia (Spain); Perez, J.C. [MESA - Schneider Electric, Gatica 48110 (Spain)

    2010-12-15

    The design and development of current-limiting power fuses requires considerable time and expense on testing to verify that the maximum temperature limits under the rated current established in international standards are not exceeded. This paper presents a new methodology that reproduces the thermal behaviour of high voltage current-limiting fuses under currents up to the rated value and so, it reduces the need for testing as prototypes, more similar to the final design, can be obtained. Firstly, the methodology solves the transient heating process of the fuse to obtain the values of the power dissipated and the heat transfer coefficient, corresponding to the steady state condition. Once these values have been calculated, the temperature distribution at the surface of the complete fuse is obtained. The validity of the method proposed has been verified by comparison of the numerical values calculated with those obtained by testing real fuses. (author)

  5. Lecithin:Cholesterol Acyltransferase (LCAT) Deficiency Promotes Differentiation of Satellite Cells to Brown Adipocytes in a Cholesterol-dependent Manner.

    Science.gov (United States)

    Nesan, Dinushan; Tavallaee, Ghazaleh; Koh, Deborah; Bashiri, Amir; Abdin, Rawand; Ng, Dominic S

    2015-12-18

    Our laboratory previously reported that lecithin:cholesterol acyltransferase (LCAT) and LDL receptor double knock-out mice (Ldlr(-/-)xLcat(-/-) or DKO) spontaneously develop functioning ectopic brown adipose tissue (BAT) in skeletal muscle, putatively contributing to protection from the diet-induced obesity phenotype. Here we further investigated their developmental origin and the mechanistic role of LCAT deficiency. Gene profiling of skeletal muscle in DKO newborns and adults revealed a classical lineage. Primary quiescent satellite cells (SC) from chow-fed DKO mice, not in Ldlr(-/-)xLcat(+/+) single-knock-out (SKO) or C57BL/6 wild type, were found to (i) express exclusively classical BAT-selective genes, (ii) be primed to express key functional BAT genes, and (iii) exhibit markedly increased ex vivo adipogenic differentiation into brown adipocytes. This gene priming effect was abrogated upon feeding the mice a 2% high cholesterol diet in association with accumulation of excess intracellular cholesterol. Ex vivo cholesterol loading of chow-fed DKO SC recapitulated the effect, indicating that cellular cholesterol is a key regulator of SC-to-BAT differentiation. Comparing adipogenicity of Ldlr(+/+)xLcat(-/-) (LCAT-KO) SC with DKO SC identified a role for LCAT deficiency in priming SC to express BAT genes. Additionally, we found that reduced cellular cholesterol is important for adipogenic differentiation, evidenced by increased induction of adipogenesis in cholesterol-depleted SC from both LCAT-KO and SKO mice. Taken together, we conclude that ectopic BAT in DKO mice is classical in origin, and its development begins in utero. We further showed complementary roles of LCAT deficiency and cellular cholesterol reduction in the SC-to-BAT adipogenesis. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Fused silica challenges in sensitive space applications

    Science.gov (United States)

    Criddle, Josephine; Nürnberg, Frank; Sawyer, Robert; Bauer, Peter; Langner, Andreas; Schötz, Gerhard

    2016-07-01

    Space bound as well as earthbound spectroscopy of extra-terrestrial objects finds its challenge in light sources with low intensities. High transmission for every optical element along the light path requires optical materials with outstanding performance to enable the measurement of even a one-photon event. Using the Lunar Laser Ranging Project and the LIGO and VIRGO Gravitational Wave Detectors as examples, the influence of the optical properties of fused silica will be described. The Visible and Infrared Surveillance Telescope for Astronomy (VISTA) points out the material behavior in the NIR regime, where the chemical composition of optical materials changes the performance. Special fibers are often used in combination with optical elements as light guides to the spectroscopic application. In an extended spectral range between 350 and 2,200 nm Heraeus developed STU fiber preforms dedicated for broad band spectroscopy in astronomy. STU fibers in the broad spectral range as well as SSU fibers for UV transmission (180 - 400 nm) show also high gamma radiation resistance which allows space applications.

  7. AMPKα, C/EBPβ, CPT1β, GPR43, PPARγ, and SCD Gene Expression in Single- and Co-cultured Bovine Satellite Cells and Intramuscular Preadipocytes Treated with Palmitic, Stearic, Oleic, and Linoleic Acid

    OpenAIRE

    Choi, S H; Park, S. K.; B. J. Johnson; Chung, K. Y.; Choi, C. W.; Kim, K. H.; Kim, W. Y.; Smith, B.

    2015-01-01

    We previously demonstrated that bovine subcutaneous preadipocytes promote adipogenic gene expression in muscle satellite cells in a co-culture system. Herein we hypothesize that saturated fatty acids would promote adipogenic/lipogenic gene expression, whereas mono- and polyunsaturated fatty acids would have the opposite effect. Bovine semimembranosus satellite cells (BSC) and intramuscular preadipocytes (IPA) were isolated from crossbred steers and cultured with 10% fetal bovine serum (FBS)/D...

  8. Influenza a virus assembly intermediates fuse in the cytoplasm.

    Directory of Open Access Journals (Sweden)

    Seema S Lakdawala

    2014-03-01

    Full Text Available Reassortment of influenza viral RNA (vRNA segments in co-infected cells can lead to the emergence of viruses with pandemic potential. Replication of influenza vRNA occurs in the nucleus of infected cells, while progeny virions bud from the plasma membrane. However, the intracellular mechanics of vRNA assembly into progeny virions is not well understood. Here we used recent advances in microscopy to explore vRNA assembly and transport during a productive infection. We visualized four distinct vRNA segments within a single cell using fluorescent in situ hybridization (FISH and observed that foci containing more than one vRNA segment were found at the external nuclear periphery, suggesting that vRNA segments are not exported to the cytoplasm individually. Although many cytoplasmic foci contain multiple vRNA segments, not all vRNA species are present in every focus, indicating that assembly of all eight vRNA segments does not occur prior to export from the nucleus. To extend the observations made in fixed cells, we used a virus that encodes GFP fused to the viral polymerase acidic (PA protein (WSN PA-GFP to explore the dynamics of vRNA assembly in live cells during a productive infection. Since WSN PA-GFP colocalizes with viral nucleoprotein and influenza vRNA segments, we used it as a surrogate for visualizing vRNA transport in 3D and at high speed by inverted selective-plane illumination microscopy. We observed cytoplasmic PA-GFP foci colocalizing and traveling together en route to the plasma membrane. Our data strongly support a model in which vRNA segments are exported from the nucleus as complexes that assemble en route to the plasma membrane through dynamic colocalization events in the cytoplasm.

  9. High-sensitive bioorthogonal SERS tag for live cancer cell imaging by self-assembling core-satellites structure gold-silver nanocomposite.

    Science.gov (United States)

    Chen, Meng; Zhang, Ling; Gao, Mingxia; Zhang, Xiangmin

    2017-09-01

    A novel, high-sensitivity, biocompatible SERS tag with core-shell structure based on gold nanoparticles containing alkynyl molecule core -silver nanoparticle satellites shell was fabricated for the first time to be used for live cancer cells Surface enhanced Raman scattering (SERS) imaging. (E)-2-((4-(phenylethynyl)benzylidene) amino) ethanethiol (PBAT) synthesized facilely in our lab is the Raman-silence region reporter which is advantage for bioorthogonal SERS cell imaging. In order to enhance the intensity of the Raman tags for live cancer cell imaging, a series of news measures have been adopted. Firstly, reporter molecules of the PBAT were added twice, which is embedded in the gold core with the reduction of tetrachloroaurate and then PBAT is conjugated again on disperse gold nanoparticles (PBAT-Au). Furthermore, numerous Ag nanoparticles self-assembly were densely arranged around PBAT-Au core surface (PBAT- Au@Ag), just like a circle of satellites cluster, which produce obvious "hot spots" effects enhancing the signal of the Raman tags enormously. Finally, Bovine serum albumin (BSA) and polydopamine (PDA) coated on the PBAT- Au@Ag successively, defined as (PBAT-Au@Ag@BSA@PDA), which make as-synthesized nanocomposites own features of bio-compatibility and facilitates antibody modification. Compared with Au@PBAT@PDA, PBAT-Au@Ag@BSA@PDA with core-shell satellites structure showed 10-fold increase in the Raman signals intensity. Moreover, PBAT-Au@Ag@BSA@PDA nanocomposites were successfully applied in the Raman imaging of human glioma cells (U251) by the recognition of the anti-epidermal growth factor receptor (EGFR). All experimental results demonstrated that the nanocomposites have high value and huge potential application in the live cancer cells imaging and biomedical diagnostics in the near future. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Scientific Satellites

    Science.gov (United States)

    1967-01-01

    followed Hale’s into orbit. In 1879, Jules Verne wrote about launching small satellites with a gun possessing a muzzle velocity of 10 000 m/sec (ref. 3...was activated in 1950.11 It was located only a few tens of miles from the spot where Jules Verne had his Baltimore Gun Club fire a manned projectile to...principle, satellites can be launched by a single impulse applied at the Earth’s surface-say, with a large cannon, & la Jules Verne (sec. 8-3). In

  11. Evaluation of observation-fused regional air quality model results for population air pollution exposure estimation.

    Science.gov (United States)

    Chen, Gang; Li, Jingyi; Ying, Qi; Sherman, Seth; Perkins, Neil; Rajeshwari, Sundaram; Mendola, Pauline

    2014-07-01

    In this study, Community Multiscale Air Quality (CMAQ) model was applied to predict ambient gaseous and particulate concentrations during 2001 to 2010 in 15 hospital referral regions (HRRs) using a 36-km horizontal resolution domain. An inverse distance weighting based method was applied to produce exposure estimates based on observation-fused regional pollutant concentration fields using the differences between observations and predictions at grid cells where air quality monitors were located. Although the raw CMAQ model is capable of producing satisfying results for O3 and PM2.5 based on EPA guidelines, using the observation data fusing technique to correct CMAQ predictions leads to significant improvement of model performance for all gaseous and particulate pollutants. Regional average concentrations were calculated using five different methods: 1) inverse distance weighting of observation data alone, 2) raw CMAQ results, 3) observation-fused CMAQ results, 4) population-averaged raw CMAQ results and 5) population-averaged fused CMAQ results. It shows that while O3 (as well as NOx) monitoring networks in the HRRs are dense enough to provide consistent regional average exposure estimation based on monitoring data alone, PM2.5 observation sites (as well as monitors for CO, SO2, PM10 and PM2.5 components) are usually sparse and the difference between the average concentrations estimated by the inverse distance interpolated observations, raw CMAQ and fused CMAQ results can be significantly different. Population-weighted average should be used to account for spatial variation in pollutant concentration and population density. Using raw CMAQ results or observations alone might lead to significant biases in health outcome analyses.

  12. Evaluation of Observation-Fused Regional Air Quality Model Results for Population Air Pollution Exposure Estimation

    Science.gov (United States)

    Chen, Gang; Li, Jingyi; Ying, Qi; Sherman, Seth; Perkins, Neil; Rajeshwari, Sundaram; Mendola, Pauline

    2014-01-01

    In this study, Community Multiscale Air Quality (CMAQ) model was applied to predict ambient gaseous and particulate concentrations during 2001 to 2010 in 15 hospital referral regions (HRRs) using a 36-km horizontal resolution domain. An inverse distance weighting based method was applied to produce exposure estimates based on observation-fused regional pollutant concentration fields using the differences between observations and predictions at grid cells where air quality monitors were located. Although the raw CMAQ model is capable of producing satisfying results for O3 and PM2.5 based on EPA guidelines, using the observation data fusing technique to correct CMAQ predictions leads to significant improvement of model performance for all gaseous and particulate pollutants. Regional average concentrations were calculated using five different methods: 1) inverse distance weighting of observation data alone, 2) raw CMAQ results, 3) observation-fused CMAQ results, 4) population-averaged raw CMAQ results and 5) population-averaged fused CMAQ results. It shows that while O3 (as well as NOx) monitoring networks in the HRR regions are dense enough to provide consistent regional average exposure estimation based on monitoring data alone, PM2.5 observation sites (as well as monitors for CO, SO2, PM10 and PM2.5 components) are usually sparse and the difference between the average concentrations estimated by the inverse distance interpolated observations, raw CMAQ and fused CMAQ results can be significantly different. Population-weighted average should be used to account spatial variation in pollutant concentration and population density. Using raw CMAQ results or observations alone might lead to significant biases in health outcome analyses. PMID:24747248

  13. Correlated NOS-Imu and myf5 expression by satellite cells in mdx mouse muscle regeneration during NOS manipulation and deflazacort treatment.

    Science.gov (United States)

    Anderson, Judy E; Vargas, Cinthya

    2003-06-01

    Satellite cells, muscle precursor cells in skeletal muscle, are normally quiescent and become activated by disease or injury. A lack of dystrophin and changes in the expression or activity of neuronal nitric oxide synthase (NOS-I) affect the timing of activation in vivo. Nitric oxide synthase inhibition delays muscle repair in normal mice, and worsens muscular dystrophy in the mdx mouse, a genetic homologue of Duchenne muscular dystrophy. However, the potential role of activation and repair events mediated by nitric oxide in determining the outcome of steroid or other treatments for muscular dystrophy is not clear. We tested the hypothesis that the extent of repair in dystrophic muscles of mdx mice is partly dependent on NOS-Imu expression and activity. Myotube formation in regenerating muscle was promoted by deflazacort treatment of mdx dystrophic mice (PImu mRNA expression and activity were present in satellite cells and very new myotubes of regenerating and dystrophic muscle. Deflazacort treatment resulted in increased NOS-Imu expression in regenerating muscles in a strong and specific correlation with myf5 expression (r=0.95, PImu and myf5 expression in the diaphragm without affecting the diameter of non-regenerating fibres. These in vivo studies suggest that gains in NOS-Imu expression and nitric oxide synthase activity in satellite cells can increase the extent and speed of repair, even in the absence of dystrophin in muscle fibres. NOS-Imu may be a useful therapeutic target to augment the effects of steroidal or other treatments of muscular dystrophy.

  14. Fused Cast Alumina Refractory Products for Glass Tank Furnace

    Institute of Scientific and Technical Information of China (English)

    SHEN Keyin

    2006-01-01

    @@ 1 Subject and Scope The standard specifies the requirement, testing method, inspection rule and requirements for the labeling, packing, shipping and storing of the fused cast alumina refractory products for glass tanks.

  15. Quantification of residual stress from photonic signatures of fused silica

    Science.gov (United States)

    Cramer, K. Elliott; Hayward, Maurice; Yost, William T.

    2014-02-01

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 ± 0.54 × 10-12 Pa-1. Fused silica specimens containing impacts artificially made at NASA's Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented.

  16. Polymer Matrix Composites using Fused Deposition Modeling Technology Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Fused deposition modeling (FDM) is an additive manufacturing technology that allows fabrication of complex three-dimensional geometries layer-by-layer. The goal of...

  17. IGBT Fuses for Protection Against Explosion in Voltage Source Converters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Iov, Florin; Rasmussen, H.

    2004-01-01

    The consequences of electrical faults can be severe; not only to the equipment, but also in the worse case, to people if safety principles are not observed. Every year new applications based on DC-link Voltage Source Converters are added and the demand for protection of power electronics increases...... regarding the high-power IGBT modules. Due to the fact that the power level increases more energy is stored in the DC-link and even with an active protection, a high-power IGBT still has a risk of case rupture (explode) when a circuit failure condition occurs. A possible solution is a protection...... of the converter with standard High Speed Fuses or High Speed IGBT fuses. It is discussed that protection can be achieved by introduction of IGBT fuse located in the DC-link. Experiments show that explosion can be avoided by use of High Speed Fuse protection and the added inductance of standard High Speed...

  18. Neonatal Phosphate Nutrition Alters in Vivo and in Vitro Satellite Cell Activity in Pigs

    Directory of Open Access Journals (Sweden)

    Chad H. Stahl

    2012-05-01

    Full Text Available Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4 deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW were pair-fed liquid diets that were either PO4 adequate (0.9% total P, supra-adequate (1.2% total P in PO4 requirement or deficient (0.7% total P in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured in vitro for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (P < 0.05 sera PO4 and parathyroid hormone (PTH concentrations, while supra-adequate dietary PO4 improved (P < 0.05 feed conversion efficiency as compared to the PO4 adequate group. In vivo satellite cell proliferation was reduced (P < 0.05 among the PO4 deficient pigs, and these cells had altered in vitro expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.

  19. Effects of Vacuum of Fused Silica UV Damage

    Institute of Scientific and Technical Information of China (English)

    XU Shi-Zhen; LV Hai-Bing; YUAN Xiao-Dong; HUANG Jin; JIANG Xiao-Dong; WANG Hai-Jun; ZU Xiao-Tao; ZHENG Wan-Guo

    2008-01-01

    Damage points induced by 355 nm laser irradiation increase more quickly on the surface of fused silica in vacuum of about 10-3Pa than in atmospheric air at the same fluence.The larger concentration of point defects in vacuum is confirmed by photoluminescence intensity.X-ray photoelectron spectroscopy and infrared absorption indicate the formation of sub-stoichiometric sillca on the surface.The degradation mechanism of fused silica in vacuum is discussed.

  20. Fusing Manual and Machine Feedback in Biomedical Domain

    Science.gov (United States)

    2014-11-01

    Fusing manual and machine feedback in biomedical domain 1Jainisha Sankhavara, 1Fenny Thakrar, 2Shamayeeta Sarkar, 1Prasenjit Majumder 1DA-IICT...to obtain efficient biomedical document retrieval. We focused on fusing manual and machine feedback runs. Fusion run performs better and gives...retrieval of biomedical articles relevant for answering generic clini- cal questions about medical records. There are 30 topics provided, each

  1. ENDODONTIC MANAGEMENT OF FUSED MAXILLARY LATERAL INCISOR: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Wavdhane

    2014-11-01

    Full Text Available Fusion is a rare occurrence and its definitive diagnosis is of prime importance for successful root canal treatment. This case report discusses the endodontic and esthetic management of fused maxillary right lateral incisor. Root canal treatment was performed on the fused tooth. Nickel Chromium with ceramic crown was fabricated in the shape of lateral incisor. The patient remained asymptomatic and there was a reduction in the size of periapical radiolucency after six months.

  2. A coordinate-wise optimization algorithm for the Fused Lasso

    OpenAIRE

    Höfling, Holger; Binder, Harald; Schumacher, Martin

    2010-01-01

    L1 -penalized regression methods such as the Lasso (Tibshirani 1996) that achieve both variable selection and shrinkage have been very popular. An extension of this method is the Fused Lasso (Tibshirani and Wang 2007), which allows for the incorporation of external information into the model. In this article, we develop new and fast algorithms for solving the Fused Lasso which are based on coordinate-wise optimization. This class of algorithms has recently been applied very successfully to so...

  3. Global equation of state for a glassy material: Fused silica

    Energy Technology Data Exchange (ETDEWEB)

    Boettger, J.C.

    1994-09-01

    A new SESAME equation of state (EOS) for fused silica has been generated using the computer program GRIZZLY and will be added to the SESAME library as material number 7387. This new EOS provides better agreement with experimental data than was achieved by all previous SESAME EOSs for fused silica. Material number 7387 also constitutes the most realistic SESAME-type EOS generated for any glassy material thus far.

  4. Fusing Social Media and Mobile Analytics for Urban Sense Making

    Science.gov (United States)

    2017-05-09

    AFRL-AFOSR-JP-TR-2017-0037 Fusing Social Media and Mobile Analytics for Urban Sense-Making Archan Misra SINGAPORE MANAGEMENT UNIVERSITY Final Report...Final 3. DATES COVERED (From - To) 11 Dec 2013 to 10 Dec 2016 4. TITLE AND SUBTITLE Fusing Social Media and Mobile Analytics for Urban Sense-Making 5a...UNLIMITED: PB Public Release 13. SUPPLEMENTARY NOTES 14. ABSTRACT The proposed research was motivated by the observation that urban environments are

  5. Stimulation with monochromatic green light during incubation alters satellite cell mitotic activity and gene expression in relation to embryonic and posthatch muscle growth of broiler chickens.

    Science.gov (United States)

    Zhang, L; Zhang, H J; Wang, J; Wu, S G; Qiao, X; Yue, H Y; Yao, J H; Qi, G H

    2014-01-01

    Previous studies showed that monochromatic green light stimuli during embryogenesis accelerated posthatch body weight (BW) and pectoral muscle growth of broilers. In this experiment, we further investigated the morphological and molecular basis of this phenomenon. Fertile broiler eggs (Arbor Acres, n=880) were pre-weighed and randomly assigned to 1 of the 2 incubation treatment groups: (1) dark condition (control group), and (2) monochromatic green light group (560 nm). The monochromatic lighting systems sourced from light-emitting diode lamps and were equalized at the intensity of 15 lx at eggshell level. The dark condition was set as a commercial control from day 1 until hatching. After hatch, 120 male 1-day-old chicks from each group were housed under incandescent white light with an intensity of 30 lx at bird-head level. No effects of light stimuli during embryogenesis on hatching time, hatchability, hatching weight and bird mortality during the feeding trial period were observed in the present study. Compared with the dark condition, the BW, pectoral muscle weight and myofiber cross-sectional areas were significantly greater on 7-day-old chicks incubated under green light. Green light also increased the satellite cell mitotic activity of pectoral muscle on 1- and 3-day-old birds. In addition, green light upregulated MyoD, myogenin and myostatin mRNA expression in late embryos and/ or newly hatched chicks. These data suggest that stimulation with monochromatic green light during incubation promote muscle growth by enhancing proliferation and differentiation of satellite cells in late embryonic and newly hatched stages. Higher expression of myostatin may ultimately help prevent excessive proliferation and differentiation of satellite cells in birds incubated under green light.

  6. Activation of satellite cells and the regeneration of human skeletal muscle are expedited by ingestion of nonsteroidal anti-inflammatory medication

    DEFF Research Database (Denmark)

    Mackey, Abigail L; Rasmussen, Lotte K; Kadi, Fawzi;

    2016-01-01

    muscles of one leg. Muscle biopsies were collected from the vastus lateralis muscles before and after stimulation (2.5 h and 2, 7, and 30 d) and were assessed for satellite cells and regeneration by immunohistochemistry and real-time RT-PCR, and we also measured telomere length. After injury, and compared...... proportion of embryonic myosin(+) fibers and a residual ∼2-fold increase in mRNA levels of matrix proteins (all P telomere length shortening was not observed. In conclusion, ingestion of NSAID has a potentiating effect on Notch...

  7. Activation of P2X7 receptors in glial satellite cells reduces pain through downregulation of P2X3 receptors in nociceptive neurons

    OpenAIRE

    Chen, Yong; Zhang, Xiaofei; Wang, Congying; Li, Guangwen; Gu, Yanping; Huang, Li-Yen Mae

    2008-01-01

    Purinergic ionotropic P2X7 receptors (P2X7Rs) are closely associated with excitotoxicity and nociception. Inhibition of P2X7R activation has been considered as a potentially useful strategy to improve recovery from spinal cord injury and reduce inflammatory damage to trauma. The physiological functions of P2X7Rs, however, are poorly understood, even though such information is essential for making the P2X7R an effective therapeutic target. We show here that P2X7Rs in satellite cells of dorsal ...

  8. Strength training increases the size of the satellite cell pool in type I and II fibres of chronically painful trapezius muscle in females

    DEFF Research Database (Denmark)

    Mackey, Abigail; Andersen, Lars L; Frandsen, Ulrik

    2011-01-01

    While strength training has been shown to be effective in mediating hypertrophy and reducing pain in trapezius myalgia, responses at the cellular level have not previously been studied. This study investigated the potential of strength training targeting the affected muscles (SST, n = 18......) and general fitness training (GFT, n = 16) to augment the satellite cell (SC) and macrophage pools in the trapezius muscles of women diagnosed with trapezius myalgia. A group receiving general health information (REF, n = 8) served as a control. Muscle biopsies were collected from the trapezius muscles...... hypertrophy (r = -0.669, P = 0.005). SST also resulted in a 74% enhancement of the trapezius macrophage content (P

  9. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    Science.gov (United States)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  10. Long-term insulin-like growth factor-I expression in skeletal muscles attenuates the enhanced in vitro proliferation ability of the resident satellite cells in transgenic mice

    Science.gov (United States)

    Chakravarthy, M. V.; Fiorotto, M. L.; Schwartz, R. J.; Booth, F. W.

    2001-01-01

    Insulin-like growth factor-I (IGF-I) overexpression for 1-month in mouse skeletal muscle increases satellite cell proliferation potential. However, it is unknown whether this beneficial enhancement by IGF-I expression would persist over a longer-term duration in aged mice. This is an important issue to address if a prolonged course of IGF-I is to be used clinically in muscle-wasting conditions where satellite cells may become limiting. Using the IGF-I transgenic (IGF-I Tg) mouse that selectively expresses the IGF-I transgene in striated muscles, we found that 18-months of continuous IGF-I overexpression led to a loss in the enhanced in vitro proliferative capacity of satellite cells from Tg skeletal muscles. Also 18-month-old IGF-I Tg satellite cells lost the enhanced BrdU incorporation, greater pRb and Akt phosphorylations, and decreased p27(Kip1) levels initially observed in cells from 1-month-old IGF-I Tg mice. The levels of those biochemical markers reverted to similar values seen in the 18-months WT littermates. These findings, therefore, suggest that there is no further beneficial effect on enhancing satellite cell proliferation ability with persistent long-term expression of IGF-I in skeletal muscles of these transgenic mice.

  11. Satellite Sounder Observations of Contrasting Tropospheric Moisture Transport Regimes: Saharan Air Layers, Hadley Cells, and Atmospheric Rivers

    Energy Technology Data Exchange (ETDEWEB)

    Nalli, Nicholas R.; Barnet, Christopher D.; Reale, Tony; Liu, Quanhua; Morris, Vernon R.; Spackman, J. Ryan; Joseph, Everette; Tan, Changyi; Sun, Bomin; Tilley, Frank; Leung, L. Ruby; Wolfe, Daniel

    2016-12-01

    This paper examines the performance of satellite sounder atmospheric vertical moisture proles (AVMP) under tropospheric conditions encompassing moisture contrasts driven by convection and advection transport mechanisms, specifically Atlantic Ocean Saharan air layers (SALs) and Pacific Ocean moisture conveyer belts (MCBs) commonly referred to as atmospheric rivers (ARs), both of these being mesoscale to synoptic meteorological phenomena within the vicinity of subtropical Hadley subsidence zones. Operational AVMP environmental data records retrieved from the Suomi National Polar-orbiting Partnership (SNPP) NOAA-Unique Combined Atmospheric Processing System (NUCAPS) are collocated with dedicated radiosonde observations (RAOBs) obtained from ocean-based intensive field campaigns; these RAOBs provide uniquely independent correlative truth data not assimilated into numerical weather prediction models for satellite sounder validation over open ocean. Using these marine-based data, we empirically assess the performance of the operational NUCAPS AVMP product for detecting and resolving these tropospheric moisture features over otherwise RAOB-sparse regions.

  12. Fused Lasso Screening Rules via the Monotonicity of Subdifferentials.

    Science.gov (United States)

    Wang, Jie; Fan, Wei; Ye, Jieping

    2015-09-01

    Fused Lasso is a popular regression technique that encodes the smoothness of the data. It has been applied successfully to many applications with a smooth feature structure. However, the computational cost of the existing solvers for fused Lasso is prohibitive when the feature dimension is extremely large. In this paper, we propose novel screening rules that are able to quickly identity the adjacent features with the same coefficients. As a result, the number of variables to be estimated can be significantly reduced, leading to substantial savings in computational cost and memory usage. To the best of our knowledge, the proposed approach is the first attempt to develop screening methods for the fused Lasso problem with general data matrix. Our major contributions are: 1) we derive a new dual formulation of fused Lasso that comes with several desirable properties; 2) we show that the new dual formulation of fused Lasso is equivalent to that of the standard Lasso by two affine transformations; 3) we propose a novel framework for developing effective and efficient screening rules for fused Lasso via the monotonicity of the subdifferentials (FLAMS). Some appealing features of FLAMS are: 1) our methods are safe in the sense that the detected adjacent features are guaranteed to have the same coefficients; 2) the dataset needs to be scanned only once to run the screening, whose computational cost is negligible compared to that of solving the fused Lasso; (3) FLAMS is independent of the solvers and can be integrated with any existing solvers. We have evaluated the proposed FLAMS rules on both synthetic and real datasets. The experiments indicate that FLAMS is very effective in identifying the adjacent features with the same coefficients. The speedup gained by FLAMS can be orders of magnitude.

  13. 30 CFR 56.12037 - Fuses in high-potential circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fuses in high-potential circuits. 56.12037... § 56.12037 Fuses in high-potential circuits. Fuse tongs or hot line tools shall be used when fuses are removed or replaced in high-potential circuits....

  14. 30 CFR 57.12037 - Fuses in high-potential circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fuses in high-potential circuits. 57.12037... Electricity Surface and Underground § 57.12037 Fuses in high-potential circuits. Fuse tongs or hotline tools, shall be used when fuses are removed or replaced in high-potential circuits....

  15. Loss of oxidative defense and potential blockade of satellite cell maturation in the skeletal muscle of patients with cancer but not in the healthy elderly.

    Science.gov (United States)

    Brzeszczyńska, Joanna; Johns, Neil; Schilb, Alain; Degen, Simone; Degen, Martin; Langen, Ramon; Schols, Annemie; Glass, David J; Roubenoff, Ronenn; Greig, Carolyn A; Jacobi, Carsten; Fearon, Kenneth Ch; Ross, James A

    2016-08-01

    Muscle wasting in old age or cancer may result from failed myofiber regeneration and/or accelerated atrophy. This study aimed to determine from transcriptomic analysis of human muscle the integrity of the cellular stress response system in relation to satellite cell differentiation or apoptosis in patients with cancer (weight-stable (CWS) or weight-losing (CWL)) or healthy elderly (HE) when compared with healthy middle-aged controls (HMA). 28 patients with cancer (CWS: 18 and CWL: 10), HE: 21 and HMA: 20 underwent biopsy of quadriceps muscle. The expression of transcription factors for muscle regeneration (Pax3, Pax7 and MyoD) was increased in CWS and HE compared with HMA (p≤0.001). In contrast, the expression of the late myogenic differentiation marker MyoG was reduced in CWS and CWL but increased in HE (p≤0.0001). Bax was significantly increased in CWS, CWL and HE (p≤0.0001). Expression of the oxidative defense genes SOD2, GCLM, and Nrf2 was decreased in CWS and CWL but increased in HE (p≤0.0001). There is evidence for blockade of satellite cell maturation, upregulation of apoptosis and reduced oxidative defense in the muscle of cancer patients. In the healthy elderly the potential for differentiation and oxidative defense is maintained.

  16. Bifunctional fused polypeptide inhibits the growth and metastasis of breast cancer

    Directory of Open Access Journals (Sweden)

    Liang AL

    2015-10-01

    Full Text Available Ai-Ling Liang,1–3,* Hai-Li Qian,4,* Ting-Ting Zhang,1–3 Ning Zhou,1–3 Hai-Juan Wang,4 Xi-Ting Men,4 Wei Qi,5 Ping-Ping Zhang,6 Ming Fu,4 Xiao Liang,4 Chen Lin,4 Yong-Jun Liu1–3 1Medical Molecular Diagnostics Key Laboratory of Guangdong, 2Department of Biochemistry and Molecular Biology, 3Department of Clinical Biochemistry, Guangdong Medical University, Dongguan, Guangdong, 4State Key Laboratory of Molecular Oncology, Cancer Institute, Chinese Academy of Medical Sciences, Beijing, 5Electroencephalogram Room, 6Department of Orthopedics, Guangdong Medical University Affiliated Hospital, Zhanjiang, Guangdong, People’s Republic of China *These authors contributed equally to this study Abstract: Breast cancer is the most common cancer and the leading cause of cancer-related death among women worldwide, with urgent need to develop new therapeutics. Targeted therapy is a promising strategy for breast cancer therapy. Stromal-derived factor-1/CXC chemokine receptor 4 (CXCR4 has been implicated in the metastasis of breast cancer, which renders it to be therapeutic target. This study aimed to evaluate the anticancer effect of fused TAT–DV1–BH3 polypeptide, an antagonist of CXCR4, and investigate the underlying mechanism for the cancer cell-killing effect in the treatment of breast cancer in vitro and in vivo. This results in a potent inhibitory effect of fused TAT–DV1–BH3 polypeptide on tumor growth and metastasis in nude mice bearing established MDA-MB-231 tumors. Fused TAT–DV1–BH3 polypeptide inhibited the proliferation of MDA-MB-231 and MCF-7 cells but did not affect that of HEK-293 cells. The fused TAT–DV1–BH3 polypeptide colocalized with mitochondria and exhibited a proapoptotic effect through the regulation of caspase-9 and -3. Furthermore, the fused TAT–DV1–BH3 polypeptide suppressed the migration and invasion of the highly metastatic breast cancer cell line MDA-MB-231 in a concentration-dependent manner. Notably, the

  17. Quantification of Residual Stress from Photonic Signatures of Fused Silica

    Science.gov (United States)

    Cramer, K. Elliott; Hayward, Maurice; Yost, William E.

    2013-01-01

    A commercially available grey-field polariscope (GFP) instrument for photoelastic examination is used to assess impact damage inflicted upon the outer-most pane of Space Shuttle windows made from fused silica. A method and apparatus for calibration of the stress-optic coefficient using four-point bending is discussed. The results are validated on known material (acrylic) and are found to agree with literature values to within 6%. The calibration procedure is then applied to fused-silica specimens and the stress-optic coefficient is determined to be 2.43 +/- 0.54 x 10(exp -12)/Pa. Fused silica specimens containing impacts artificially made at NASA's Hypervelocity Impact Technology Facility (HIT-F), to simulate damage typical during space flight, are examined. The damage sites are cored from fused silica window carcasses and examined with the GFP. The calibrated GFP measurements of residual stress patterns surrounding the damage sites are presented. Keywords: Glass, fused silica, photoelasticity, residual stress

  18. A Flexible Spatiotemporal Method for Fusing Satellite Images with Different Resolutions

    Science.gov (United States)

    Studies of land surface dynamics in heterogeneous landscapes often require remote sensing data with high acquisition frequency and high spatial resolution. However, no single sensor meets this requirement. This study presents a new spatiotemporal data fusion method, the Flexible Spatiotemporal DAta ...

  19. A flexible spatiotemporal method for fusing satellite images with different resolutions

    Science.gov (United States)

    Xiaolin Zhu; Eileen H. Helmer; Feng Gao; Desheng Liu; Jin Chen; Michael A. Lefsky

    2016-01-01

    Studies of land surface dynamics in heterogeneous landscapes often require remote sensing datawith high acquisition frequency and high spatial resolution. However, no single sensor meets this requirement. This study presents a new spatiotemporal data fusion method, the Flexible Spatiotemporal DAta Fusion (FSDAF) method, to generate synthesized frequent high spatial...

  20. 负载人蛔虫和猪蛔虫抗原树突状细胞影响T细胞亚群活性研究%Comparative analysis of T cell subsets response induced by DC fused with Ag of Ascaris lumbricoides and Ascaris suum

    Institute of Scientific and Technical Information of China (English)

    祝伟; 黄川; 黄艳琴; 胡银英; 戴志芳; 袁芳; 袁铿

    2013-01-01

    目的 探讨人蛔虫和猪蛔虫抗原致敏树突状细胞(DendriticCell,DC)对T细胞亚群活性的调节作用差异.方法用IL-4和GM-CSF联合体外诱导小鼠骨髓源性DC,分别负载两种不同基因型蛔虫抗原,由低到高各分3组,并设置空白对照进行培养.负载了蛔虫抗原的DC,按1∶25的比例分别与同源性脾淋巴细胞共培养.用流式细胞术、ELISA和qPCR分别检测比较负载后DC表面分子表达变化及其混合淋巴细胞反应Th1/Th2类细胞因子表达的变化和FoxP3 mRNA的表达水平.结果 骨髓细胞诱导所得初始DC高表达表面分子CD86(85.5%)、CD83(38.24%)和CD80(94%),在负载蛔虫抗原后,各组仍高表达,但CD83和CD80较初始DC有所下降,且猪蛔虫抗原组和人蛔虫抗原组分别低和高于空白对照组.ELISA检测显示,各时间段实验组TNF-α 的表达量都低于对照组,且差异都有统计学意义(P<0.05):IL-10在各组的表达量随时间延长而增加,各时间段的相同浓度除24h外,人蛔虫抗原组高于猪蛔虫抗原组(P<0.05).qPCR结果显示,相对于人蛔虫抗原组Foxp3 mRNA的表达量,空白对照组和住蛔虫抗原组各个时间段都较低,且都与前者存在差异性(P<0.05);人蛔虫抗原组的表达量在短期内增加明显,但又随时间而减少;猪蛔虫抗原组则先增后减,但都与空白对照组间无差异性(P>0.05).结论 负载了人蛔虫抗原的DC能更强促进淋巴细胞Th2类反应和Foxp3表达,影响调节性T细胞功能.%To investigate comparatively the different responses of T cell subsets induced by dendritic cell (DC) fused re spectively with three different concentrations of A.lumbricoides and A.suum antigens (Ag),the levels of the expression of DC surface moleculars,Thl/Th2 cytokines and Foxp3 mRNA in different MLR groups,which were antigen-loaded DC co-cultured with C57BL/6 mouse-derived splenic lymphocytes at the effect-target ratio of 1 ∶ 25.were detected

  1. Improved immunogenicity of fusions between ethanol-treated cancer cells and dendritic cells exposed to dual TLR stimulation

    National Research Council Canada - National Science Library

    Koido, Shigeo; Homma, Sadamu; Okamoto, Masato; Namiki, Yoshihisa; Kan, Shin; Takakura, Kazuki; Kajihara, Mikio; Uchiyama, Kan; Hara, Eiich; Ohkusa, Toshifumi; Gong, Jianlin; Tajiri, Hisao

    2013-01-01

    ...) fused to whole cancer cells. We have recently revealed that ethanol-treated neoplastic cells fused to DCs exposed to 2 Toll-like receptor agonists efficiently induce cytotoxic T lymphocytes via TGF...

  2. Identification and Characterization of the Dermal Panniculus Carnosus Muscle Stem Cells

    Directory of Open Access Journals (Sweden)

    Neia Naldaiz-Gastesi

    2016-09-01

    Full Text Available The dermal Panniculus carnosus (PC muscle is important for wound contraction in lower mammals and represents an interesting model of muscle regeneration due to its high cell turnover. The resident satellite cells (the bona fide muscle stem cells remain poorly characterized. Here we analyzed PC satellite cells with regard to developmental origin and purported function. Lineage tracing shows that they originate in Myf5+, Pax3/Pax7+ cell populations. Skin and muscle wounding increased PC myofiber turnover, with the satellite cell progeny being involved in muscle regeneration but with no detectable contribution to the wound-bed myofibroblasts. Since hematopoietic stem cells fuse to PC myofibers in the absence of injury, we also studied the contribution of bone marrow-derived cells to the PC satellite cell compartment, demonstrating that cells of donor origin are capable of repopulating the PC muscle stem cell niche after irradiation and bone marrow transplantation but may not fully acquire the relevant myogenic commitment.

  3. On Fusing Recursive Traversals of K-d Trees

    Energy Technology Data Exchange (ETDEWEB)

    Rajbhandari, Samyam; Kim, Jinsung; Krishnamoorthy, Sriram; Pouchet, Louis-Noel; Rastello, Fabrice; Harrison, Robert J.; Sadayappan, Ponnuswamy

    2016-03-17

    Loop fusion is a key program transformation for data locality optimization that is implemented in production compilers. But optimizing compilers currently cannot exploit fusion opportunities across a set of recursive tree traversal computations with producer-consumer relationships. In this paper, we develop a compile-time approach to dependence characterization and program transformation to enable fusion across recursively specified traversals over k-ary trees. We present the FuseT source-to-source code transformation framework to automatically generate fused composite recursive operators from an input program containing a sequence of primitive recursive operators. We use our framework to implement fused operators for MADNESS, Multiresolution Adaptive Numerical Environment for Scientific Simulation. We show that locality optimization through fusion can offer more than an order of magnitude performance improvement.

  4. Aromaticity Competition in Differentially Fused Borepin-Containing Polycyclic Aromatics.

    Science.gov (United States)

    Messersmith, Reid E; Siegler, Maxime A; Tovar, John D

    2016-07-01

    This report describes the synthesis and characterization of a series of borepin-based polycyclic aromatics bearing two different arene fusions. The borepin synthesis features streamlined Ti-mediated alkyne reduction, leading to Z-olefins, followed by direct lithiation and borepin formation. These molecules allow for an assessment of aromatic competition between the fused rings and the central borepin core. Crystallographic, magnetic, and computational studies yielded insights about the aromaticity of novel, differentially fused [b,f]borepins and allowed for comparison to literature compounds. Multiple borepin motifs were also incorporated into polycyclic aromatics with five or six rings in the main backbone, and their properties were also evaluated.

  5. Bonding energy of Sylgard on fused quartz: an experimental investigation

    Science.gov (United States)

    Liu, C.; Yeager, J. D.; Ramos, K. J.

    2015-02-01

    The bonding energy between the polymer Sylgard and fused quartz is determined experimentally using a miniature bulge test combined with three-dimensional digital image correlation (3D-DIC). Based on the experimental observation, Mindlin plate theory is used to compute the bonding energy (adhesive energy or surface energy) between the Sylgard and the fused quartz. The experimental results demonstrate that the combination of the miniature bulge test and the 3D-DIC provides a viable tool to directly measure interfacial and bonding properties.

  6. Iatrogenic mid-root perforation of fused teeth

    Directory of Open Access Journals (Sweden)

    Vijay Kumar

    2012-01-01

    Full Text Available Fusion is defined as a union between the dentin and/or enamel of two or more distinct dental sprouts that occurs at any stage of the dental organ. Its prevalence ranges from 0.5%-2.5% in the primary dentition alone and 0.1%-1% of the primary as well as the permanent dentition. These fused teeth can cause various problems such as caries, periodontal disease, abnormal eruption, impaction or an ectopic eruption of an adjacent tooth and reported in the literature. However this paper documented an unusual case of iatrogenic root perforation of fused permanent lower anterior teeth during inter maxillary fixation.

  7. Role of the mTORC1 complex in satellite cell activation by RNA-induced mitochondrial restoration: dual control of cyclin D1 through microRNAs.

    Science.gov (United States)

    Jash, Sukanta; Dhar, Gunjan; Ghosh, Utpalendu; Adhya, Samit

    2014-10-01

    During myogenesis, satellite stem cells (SCs) are induced to proliferate and differentiate to myogenic precursors. The role of energy sensors such as the AMP-activated protein kinase (AMPK) and the mammalian Target of Rapamycin (mTOR) in SC activation is unclear. We previously observed that upregulation of ATP through RNA-mediated mitochondrial restoration (MR) accelerates SC activation following skeletal muscle injury. We show here that during regeneration, the AMPK-CRTC2-CREB and Raptor-mTORC-4EBP1 pathways were rapidly activated. The phosho-CRTC2-CREB complex was essential for myogenesis and activated transcription of the critical cell cycle regulator cyclin D1 (Ccnd1). Knockdown (KD) of either mTORC or its subunit Raptor delayed SC activation without influencing the differentiation program. KD of 4EBP1 had no effect on SC activation but enhanced myofiber size. mTORC1 positively regulated Ccnd1 translation but destabilized Ccnd1 mRNA. These antithetical effects of mTORC1 were mediated by two microRNAs (miRs) targeted to the 3' untranslated region (UTR) of Ccnd1 mRNA: miR-1 was downregulated in mTORC-KD muscle, and depletion of miR-1 resulted in increased levels of mRNA without any effect on Ccnd1 protein. In contrast, miR-26a was upregulated upon mTORC depletion, while anti-miR-26a oligonucleotide specifically stimulated Ccnd1 protein expression. Thus, mTORC may act as a timer of satellite cell proliferation during myogenesis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  8. Satellite cells in slow and fast rat muscles differ in respect to acetylcholinesterase regulation mechanisms they convey to their descendant myofibers during regeneration.

    Science.gov (United States)

    Dolenc, I; Crne-Finderle, N; Erzen, I; Sketelj, J

    1994-02-01

    The hypothesis of satellite cell diversity in slow and fast mammalian muscles was tested by examining acetylcholinesterase (AChE) regulation in muscles regenerating 1) under conditions of muscle disuse (tenotomy, leg immobilization) in which the pattern of neural stimulation is changed, and 2) after cross-transplantation when the regenerating muscle develops under a foreign neural stimulation pattern. Soleus (SOL) and extensor digitorum longus (EDL) muscles of the rat were allowed to regenerate after ischemic-toxic injury either in their own sites or had been cross-transplanted to the site of the other muscle. Molecular forms of AChE in regenerating muscles were analyzed by velocity sedimentation in linear sucrose gradients. Neither tenotomy nor limb immobilization significantly affected the characteristic pattern of AChE molecular forms in regenerating SOL muscles, suggesting that the neural stimulation pattern is probably not decisive for its induction. During an early phase of regeneration, the general pattern of AChE molecular forms in the cross-transplanted regenerating muscle was predominantly determined by the type of its muscle of origin, and much less by the innervating nerve which exerted only a modest modifying effect. However, alkali-resistant myofibrillar ATPase activity on which the separation of muscle fibers into type I and type II is based, was determined predominantly by the motor nerve innervating the regenerating muscle. Mature regenerated EDL muscles (13 weeks after injury) which had been innervated by the SOL nerve became virtually indistinguishable from the SOL muscles in regard to their pattern of AChE molecular forms. However, AChE patterns of mature regenerated SOL muscles that had been innervated by the EDL nerve still displayed some features of the SOL pattern. In regard to AChE regulation, muscle satellite cells from slow or fast rat muscles convey to their descendant myotubes the information shifting their initial development in the

  9. Mammalian Skeletal Muscle Fibres Promote Non-Muscle Stem Cells and Non-Stem Cells to Adopt Myogenic Characteristics

    Directory of Open Access Journals (Sweden)

    Taryn Morash

    2017-01-01

    Full Text Available Skeletal muscle fibres are unique cells in large animals, often composed of thousands of post-mitotic nuclei. Following skeletal muscle damage, resident stem cells, called satellite cells, commit to myogenic differentiation and migrate to carry out repair. Satellite stem cells migrate on muscle fibres through amoeboid movement, which relies on dynamic cell membrane extension and retraction (blebbing. It is not known whether blebbing is due to the intrinsic properties of satellite cells, or induced by features of the myofibre surface. Here, we determined the influence of the muscle fibre matrix on two important features of muscle regeneration: the ability to migrate and to differentiate down a myogenic lineage. We show that the muscle fibre is able to induce amoeboid movement in non-muscle stem cells and non-stem cells. Secondly, we show that prolonged co-culture on myofibres caused amniotic fluid stem cells and breast cancer cells to express MyoD, a key myogenic determinant. Finally, we show that amniotic fluid stem cells co-cultured on myofibres are able to fuse and make myotubes that express Myosin Heavy Chain.

  10. Study on the Expression of MMP-2 and MMP-13 in Human Gingival Fibroblast Cells of Porcelain Fused to Metal Crown%烤瓷冠基底合金影响人牙龈成纤维细胞MMP-2、MMP-13表达实验探讨

    Institute of Scientific and Technical Information of China (English)

    刘丽梅

    2016-01-01

    Objective To observe the effects of different kinds of porcelain fused to metal crown on the expression of MMP-2 and MMP-13 in human gingival fibroblast cells.Methods The preparation of pure titanium and cobalt chromium, nickel chromium alloy and gold extraction, by means of a modiifed tissue to ifbroblast cells were cultured on the gums around, after leaching liquid immersion, were collected on a sample cell supernatant, the expression level of MMP-13 was determined as the sample determination method for ILISA determination. Results The expression of CO Cr alloy and Ni Cr alloy MKMP-13 was higher than the negative control group and experimental group, comparison of various indexes, the difference was statistically signiifcant (P0.05) in the gold and pure titanium alloy group.Conclusion Co Cr alloy and Ni Cr alloy MKMP-13 high expression level, to a certain extent will damage the gingival ifbroblast; gold, pure titanium alloy biocompatibility is good.%目的:观察不同种类烤瓷牙金属基底冠浸提液对人牙龈成纤维细胞中 MMP-2、MMP-13表达水平的影响。方法制备纯钛、钴铬、镍铬和金合金提取液,通过组织块改良的方法来对牙龈周围的纤维细胞进行培养,经过浸提液浸泡之后,分别收集样本上的细胞清液,作为MMP-13表达水平的测定样本,测定方法为ILISA测定法。结果钴铬合金和镍铬合金MKMP-13表达水平高于阴性对照组和其他实验组,各项指标对比,差异有统计学意义(P<0.05);金、纯钛合金组MMP-13表达水平与阴性对照组比较,差异无统计学意义(P>0.05)。结论钴铬合金和镍铬合金MKMP-13表达水平较高,一定程度上会损伤牙龈成纤维细胞;金、纯钛合金生物相容性比较好。

  11. Spectrally Consistent Satellite Image Fusion with Improved Image Priors

    DEFF Research Database (Denmark)

    Nielsen, Allan Aasbjerg; Aanæs, Henrik; Jensen, Thomas B.S.;

    2006-01-01

    Here an improvement to our previous framework for satellite image fusion is presented. A framework purely based on the sensor physics and on prior assumptions on the fused image. The contributions of this paper are two fold. Firstly, a method for ensuring 100% spectrally consistency is proposed......, even when more sophisticated image priors are applied. Secondly, a better image prior is introduced, via data-dependent image smoothing....

  12. Geostationary Satellite (GOES) Images

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Visible and Infrared satellite imagery taken from radiometer instruments on SMS (ATS) and GOES satellites in geostationary orbit. These satellites produced...

  13. Reduction of exposure to blood donors in preterm infants submitted to red blood cell transfusions using pediatric satellite packs

    Directory of Open Access Journals (Sweden)

    Cristina Lika Uezima

    2013-09-01

    Full Text Available OBJECTIVE: In preterm newborn infants transfused with erythrocytes stored up to 28 days, to compare the reduction of blood donor exposure in two groups of infants classified according to birth weight. METHODS: A prospective study was conducted with preterm infants with birth weight <1000g (Group 1 and 1000-1499g (Group 2, born between April, 2008 and December, 2009. Neonates submitted to exchange transfusions, emergency erythrocyte transfusion, or those who died in the first 24 hours of life were excluded. Transfusions were indicated according to the local guideline using pediatric transfusion satellite bags. Demographic and clinical data, besides number of transfusions and donors were assessed. . Logistic regression analysis was performed to determine factors associated with multiple transfusions. RESULTS: 30 and 48 neonates were included in Groups 1 and 2, respectively. The percentage of newborns with more than one erythrocyte transfusion (90 versus 11%, the median number of transfusions (3 versus 1 and the median of blood donors (2 versus 1 were higher in Group 1 (p<0.001, compared to Group 2. Among those with multiple transfusions, 14 (82% and one (50% presented 50% reduction in the number of blood donors, respectively in Groups 1 and 2. Factors associated with multiple transfusions were: birth weight <1000g (OR 11.91; 95%CI 2.14-66.27 and presence of arterial umbilical catheter (OR 8.59; 95%CI 1.94-38.13, adjusted for confounders. CONCLUSIONS: The efficacy of pediatrics satellites bags on blood donor reduction was higher in preterm infants with birth weight <1000g.

  14. Neptune's small satellites

    Science.gov (United States)

    Thomas, P.

    1992-04-01

    The small satellites of Neptune and other planets discovered during the Voyager 2 mission are discussed in terms of their composition and relationship to the planetary systems. The satellite Proteus is described in terms of its orbit, five other satellites are described, and they are compared to ther small satellites and systems. Neptune's satellites are hypothesized to be related to the ring system, and the satellite Galatea is related to the confinement of the rings.

  15. Crossed fused renal ectopia: Challenges in diagnosis and management

    Directory of Open Access Journals (Sweden)

    Shailesh Solanki

    2013-01-01

    Full Text Available Aim: Crossed fused renal ectopia is a rare congenital malformation, which is reported to be usually asymptomatic but may have varied presentations. This survey was conducted to study the clinical profile and the challenges posed in the management of this entity. Materials and Methods: Retrospective analysis of 6 patients diagnosed to have crossed fused renal ectopia during 1997-2010. The diagnosis was confirmed during surgical exploration in one patient. In one patient it was detected on antenatal ultrasonography and in the other 4 patients it was detected during investigations for abdominal pain, abdominal mass, anorectal malformation and urinary tract infection. Results: The left moiety was crossed and fused with the right moiety in 4 cases. Ultrasonography was found to be a good screening investigation with useful diagnostic contributions from CT scans, radionuclide scintigraphy and magnetic resonance urography. Micturating cystourethrography revealed presence of VUR in 4 cases, 3 of whom have undergone ureteric reimplantation. Two patients required pyeloplasty for pelviureteric junction obstruction; in one of these patients the upper ureter was entrapped in the isthmus. In one patient, a non-functioning moiety resulted in nephrectomy. All children were asymptomatic at last follow-up with stable renal functions. Conclusions: Crossed fused renal ectopia was detected in most patients during investigation for other problems. It was found more commonly in boys. The left moiety was crossed to the right in the majority of cases. Associated urological problems were found in most cases and required the appropriate surgical management.

  16. Evaluation of a color fused dual-band NVG

    NARCIS (Netherlands)

    Hogervorst, M.A.; Toet, A.

    2009-01-01

    We have tested a prototype dual-band NVG system consisting of two NVGs fitted with filters that split the NVG sensitive range into a short (visual) and a long wavelength (NIR) band. The Color-the-night technique (see Hogervorst & Toet, SPIE D&S ‘08) was used to fuse the images of the two sensors. We

  17. A Review of Variable Slicing in Fused Deposition Modeling

    Science.gov (United States)

    Nadiyapara, Hitesh Hirjibhai; Pande, Sarang

    2016-06-01

    The paper presents a literature survey in the field of fused deposition of plastic wires especially in the field of slicing and deposition using extrusion of thermoplastic wires. Various researchers working in the field of computation of deposition path have used their algorithms for variable slicing. In the study, a flowchart has also been proposed for the slicing and deposition process. The algorithm already been developed by previous researcher will be used to be implemented on the fused deposition modelling machine. To demonstrate the capabilities of the fused deposition modeling machine a case study has been taken. It uses a manipulated G-code to be fed to the fused deposition modeling machine. Two types of slicing strategies, namely uniform slicing and variable slicing have been evaluated. In the uniform slicing, the slice thickness has been used for deposition is varying from 0.1 to 0.4 mm. In the variable slicing, thickness has been varied from 0.1 in the polar region to 0.4 in the equatorial region Time required and the number of slices required to deposit a hemisphere of 20 mm diameter have been compared with that using the variable slicing.

  18. Solid-state recoverable fuse functions as circuit breaker

    Science.gov (United States)

    Thomas, E. F., Jr.

    1966-01-01

    Molded, conductive-epoxy recoverable fuse protects electronic circuits during overload conditions, and then permits them to continue to function immediately after the overload condition is removed. It has low resistance at ambient temperature, and high resistance at an elevated temperature.

  19. Evaluation of a color fused dual-band NVG

    NARCIS (Netherlands)

    Hogervorst, M.A.; Toet, A.

    2009-01-01

    We designed and evaluated a dual-band Night Vision Goggles sensor system. The sensor system consists of two optically aligned NVGs fitted with filters splitting the sensitive range into a visual and a near-infrared band. The Color-the-night technique (Hogervorst & Toet, FUSION2008) was used to fuse

  20. Non-invasive management of fused upper incisors

    Directory of Open Access Journals (Sweden)

    Pouran Samimi

    2012-01-01

    Full Text Available The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8 and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10 and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.

  1. Non-invasive management of fused upper incisors.

    Science.gov (United States)

    Samimi, Pouran; Shirban, Mohammad-Reza; Arbabzadeh-Zavareh, Farahnaz

    2012-01-01

    The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case of fusion of 7 and 8, and also 9 and 10 teeth which was treated with a nonendodontic and nonsurgical conservative approach. Patient was a healthy18-year-old female with chief complaint of bad-looking teeth that in intraoral examination revealed the fusion of 7 and 8, and also 9 and 10 teeth. The space between the mesial of the 6 and 11 teeth was reconstructed. Diastema between the fused teeth was closed. A new lateral tooth was replaced between the fused teeth (7 and 8) and 6 tooth with direct fiber-reinforced composite. The space between the fused teeth (9 and 10) and also tooth 11 was partially closed. Gingival papillas were reconstructed using pink composite. The mandibular anterior missing teeth were replaced with rochett bridge. At the end of treatment the esthetic of the patient was improved. As the treatment was not invasive, major complications are not expected; however, there is potential for eventual long-term periodontal problems due to poor oral hygiene. Debonding of the rochett bridge may happen as well.

  2. New developments in fused deposition modeling of ceramics

    DEFF Research Database (Denmark)

    Bellini, Anna; Shor, L.; Guceri, S.I.

    2005-01-01

    Purpose - To shift from rapid prototyping (RP) to agile fabrication by broadening the material selection, e.g. using ceramics, hence improving the properties (e.g. mechanical properties) of fused deposition modeling (FDM) products. Design/methodology/approach - This paper presents the development...

  3. Satellite cells derived from obese humans with type 2 diabetes and differentiated into myocytes in vitro exhibit abnormal response to IL-6

    DEFF Research Database (Denmark)

    Scheele, Camilla; Nielsen, Søren; Broholm, Christa

    2012-01-01

    a resistance to IL-6. By utilizing western blot analysis, we demonstrate that IL-6Rα protein was down regulated in skeletal muscle biopsies from obese persons with and without type 2 diabetes. To further investigate the status of IL-6 signaling in skeletal muscle in obesity-associated type 2 diabetes, we......Obesity and type 2 diabetes are associated with chronically elevated systemic levels of IL-6, a pro-inflammatory cytokine with a role in skeletal muscle metabolism that signals through the IL-6 receptor (IL-6Rα). We hypothesized that skeletal muscle in obesity-associated type 2 diabetes develops...... isolated satellite cells from skeletal muscle of people that were healthy (He), obese (Ob) or were obese and had type 2 diabetes (DM), and differentiated them in vitro into myocytes. Down-regulation of IL-6Rα was conserved in Ob myocytes. In addition, acute IL-6 administration for 30, 60 and 120 minutes...

  4. Synthesis and antitumor evaluation of fluoroquinolone C3 fused heterocycles (Ⅱ): From triazolothiadiazines to pyrazolotriazoles

    Institute of Scientific and Technical Information of China (English)

    Guo Qiang Hu; Wen Long Huang; Li Li Hou; Yong Yang; Lei Yi; Song Qiang Xie; Guo Qiang Wang; Nan Nan Duan; Tie Yao Chao; Xiao Yi Wen

    2011-01-01

    To further expand an effective modified route for the shift from an antibacterial fluoroquinolone (FQ) to an antitumor FQ, two series of title compounds based on an isostere of the FQ C3 carboxylic group with two fused heterocyclic rings, [l,2,4]triazolo[3,4-6][l,3,4]thiadiazine and pyrazolo[5,l-c][l,2,4]triazole, respectively, were designed and synthesized starting from the current antibacterial FQs, and their in vitro antitumor activity against L1210, CHO cell lines were evaluated via their respective IC50 values.

  5. Synthesis, in vitro and in vivo antitumor activity of pyrazole-fused 23-hydroxybetulinic acid derivatives.

    Science.gov (United States)

    Zhang, Hengyuan; Zhu, Peiqing; Liu, Jie; Lin, Yan; Yao, Hequan; Jiang, Jieyun; Ye, Wencai; Wu, Xiaoming; Xu, Jinyi

    2015-02-01

    A collection of pyrazole-fused 23-hydroxybetulinic acid derivatives were designed, synthesized and evaluated for their antitumor activity. Most of the newly synthesized compounds exhibited significant antiproliferative activity. Especially compound 15e displayed the most potent activity with the IC50 values of 5.58 and 6.13μM against B16 and SF763 cancer cell lines, respectively. Furthermore, the significant in vivo antitumor activity of 15e was validated in H22 liver cancer and B16 melanoma xenograft mouse models. The structure-activity relationships of these 23-hydroxybetulinic acid derivatives were also discussed based on the present investigation.

  6. Cortical conditions for fused binocular vision.

    Science.gov (United States)

    Burns, B D; Pritchard, R

    1968-07-01

    1. The behaviour of twenty-six single neurones has been studied in the visual cerebral cortex of the cat's neurologically isolated and unanaesthetized forebrain. In a separate series of experiments binocular vision was investigated in five human subjects.2. Units in the cat's brain were excited by two straight, light-dark edges, projected independently, one upon each retina; these edges were given identical, artificial saccadic movements. The average response of neurones was measured from the post-stimulus-histogram (P.S.H.), which provided the probability of unit-discharge at various times after the pattern movement.3. A district within either eye-field could usually be found, such that the saccadic movements of edges passing through this part of the field, caused maximal responses; this part of each field is termed the ;representative district'. The most exciting orientations of the stimulating patterns were similar for both eyes. A cell excited by similarly oriented patterns, ;aligned' through the representative districts for each eye, exhibited dramatic spatial summation. Mutual inhibition between retinal inputs was never seen.4. The response of cortical neurones to such aligned patterns was always greater than that when one pattern was misaligned by displacement in either direction from its representative district.5. When the pattern in one eye was inverted, the cell gave less response to aligned than to misaligned patterns.6. Human subjects, viewing similar inverted patterns through a mirror stereoscope, could only obtain stable fusion with a 5 min arc misalignment of the optic axes.7. In other experiments, one eye of each subject was presented with a white rectangular bar upon a black background, while the other eye was excited by a similar black bar upon a white background. Stable fusion was reported, providing percepts of either one single low contrast bar or two neighbouring bars of high contrast. There was a range of relative pattern positions over which

  7. Satellite NG2 progenitor cells share common glutamatergic inputs with associated interneurons in the mouse dentate gyrus.

    Science.gov (United States)

    Mangin, Jean-Marie; Kunze, Albrecht; Chittajallu, Ramesh; Gallo, Vittorio

    2008-07-23

    Several studies have provided evidence that NG2-expressing (NG2(+)) progenitor cells are anatomically associated to neurons in gray matter areas. By analyzing the spatial distribution of NG2(+) cells in the hilus of the mouse dentate gyrus, we demonstrate that NG2(+) cells are indeed closely associated to interneurons. To define whether this anatomical proximity reflected a specific physiological interaction, we performed patch-clamp recordings on hilar NG2(+) cells and interneurons between 3 and 21 postnatal days. We first observed that hilar NG2(+) cells exhibit spontaneous glutamatergic EPSCs (sEPSCs) whose frequency and amplitude increase during the first 3 postnatal weeks. At the same time, the rise time and decay time of sEPSCs significantly decreased, suggesting that glutamatergic synapses in NG2(+) cells undergo a maturation process that is reminiscent of what has been reported in neurons during the same time period. We also observed that hilar interneurons and associated NG2(+) cells are similarly integrated into the local network, receiving excitatory inputs from both granule cells and CA3 pyramidal neurons. By performing pair recordings, we found that bursts of activity induced by GABAergic antagonists were strongly synchronized between both cell types and that the amplitude of these bursts was positively correlated. Finally, by applying carbachol to increase EPSC activity, we observed that closely apposed cells were more likely to exhibit synchronized EPSCs than cells separated by >200 microm. The finding that NG2(+) cells are sensing patterns of activity arising in closely associated neurons suggests that NG2(+) cell function is finely regulated by the local network.

  8. Combining electrospinning and fused deposition modeling for the fabrication of a hybrid vascular graft.

    Science.gov (United States)

    Centola, M; Rainer, A; Spadaccio, C; De Porcellinis, S; Genovese, J A; Trombetta, M

    2010-03-01

    Tissue engineering of blood vessels is a promising strategy in regenerative medicine with a broad spectrum of potential applications. However, many hurdles for tissue-engineered vascular grafts, such as poor mechanical properties, thrombogenicity and cell over-growth inside the construct, need to be overcome prior to the clinical application. To surmount these shortcomings, we developed a poly-L-lactide (PLLA)/poly-epsilon-caprolactone (PCL) scaffold releasing heparin by a combination of electrospinning and fused deposition modeling technique. PLLA/heparin scaffolds were produced by electrospinning in tubular shape and then fused deposition modeling was used to armor the tube with a single coil of PCL on the outer layer to improve mechanical properties. Scaffolds were then seeded with human mesenchymal stem cells (hMSCs) and assayed in terms of morphology, mechanical tensile strength, cell viability and differentiation. This particular scaffold design allowed the generation of both a drug delivery system amenable to surmount thrombogenic issues and a microenvironment able to induce endothelial differentiation. At the same time, the PCL external coiling improved mechanical resistance of the microfibrous scaffold. By the combination of two notable techniques in biofabrication--electrospinning and FDM--and exploiting the biological effects of heparin, we developed an ad hoc differentiating device for hMSCs seeding, able to induce differentiation into vascular endothelium.

  9. Identification of miR-2400 gene as a novel regulator in skeletal muscle satellite cells proliferation by targeting MYOG gene

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei Wei [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); College of Life Sciences and Agriculture & Forestry, Qiqihar University, Qiqihar, Heilongjiang 161006 (China); Tong, Hui Li; Sun, Xiao Feng; Hu, Qian; Yang, Yu; Li, Shu Feng [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Yan, Yun Qin, E-mail: yanyunqin@sohu.com [The Laboratory of Cell and Development, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Li, Guang Peng [The Key Laboratory of Mammal Reproductive Biology and Biotechnology Ministry of Education, Inner Mongolia University, Hohhot 010021 (China)

    2015-08-07

    MicroRNAs play critical roles in skeletal muscle development as well as in regulation of muscle cell proliferation and differentiation. Previous study in our laboratory showed that the expression level of miR-2400, a novel and unique miRNA from bovine, had significantly changed in skeletal muscle-derived satellite cells (MDSCs) during differentiation, however, the function and expression pattern for miR-2400 in MDSCs has not been fully understood. In this report, we firstly identified that the expression levels of miR-2400 were down-regulated during MDSCs differentiation by stem-loop RT-PCR. Over-expression and inhibition studies demonstrated that miR-2400 promoted MDSCs proliferation by EdU (5-ethynyl-2′ deoxyuridine) incorporation assay and immunofluorescence staining of Proliferating cell nuclear antigen (PCNA). Luciferase reporter assays showed that miR-2400 directly targeted the 3′ untranslated regions (UTRs) of myogenin (MYOG) mRNA. These data suggested that miR-2400 could promote MDSCs proliferation through targeting MYOG. Furthermore, we found that miR-2400, which was located within the eighth intron of the Wolf-Hirschhorn syndrome candidate 1-like 1 (WHSC1L1) gene, was down-regulated in MDSCs in a direct correlation with the WHSC1L1 transcript by Clustered regularly interspaced palindromic repeats interference (CRISPRi). In addition, these observations not only provided supporting evidence for the codependent expression of intronic miRNAs and their host genes in vitro, but also gave insight into the role of miR-2400 in MDSCs proliferation. - Highlights: • miR-2400 is a novel and unique miRNA from bovine. • miR-2400 could promote skeletal muscle satellite cells proliferation. • miR-2400 directly targeted the 3′ untranslated regions of MYOG mRNA. • miR-2400 could be coexpressed together with its host gene WHSC1L1.

  10. Expression of Truncated uPA Fused to EGFP in HEK293F Cells%人尿激酶型纤溶酶原激活因子截短型突变体与绿色荧光蛋白在真核细胞HEK293F中的融合表达

    Institute of Scientific and Technical Information of China (English)

    张连成; 高丽华; 张昕; 潘芸; 高招刚; 李伊培; 胡显文; 陈惠鹏

    2013-01-01

      Objective: To construct and express eukaryotic expression vectors of the truncated urokinase-type plas⁃minogen activator(uPA) fused to enhanced green fluorescent protein(EGFP). Methods: EGFP and truncated uPA genes were amplified by PCR using plasmid pIRES2-EGFP and recombinant plasmid pcDNA3.1(+)/uPA as tem⁃plates, and inserted into eukaryotic expression vector pcDNA3.1(+) sequentially. The constructed recombinant plas⁃mids were transfected into HEK293F cells, and treated with high concentration G418. The expression of recombi⁃nant proteins was detected by confocal microscopy and ELISA. Results: DNA sequencing proved that the eukaryot⁃ic expression vectors of the fusion proteins were constructed successfully. And the green fluorescent protein could be observed in cells by confocal microscopy after the transfection, and the stable expression cell lines were got af⁃ter selected by G418. ELISA showed that the secreting type fusion proteins exist in supernatant. Conclusion: Re⁃combinant plasmids have been constructed and expressed in HEK293T cells, which will contribute to further re⁃search of the interaction of uPA and its biological function in cells.%  目的:构建人尿激酶型纤溶酶原激活因子(uPA)截短型突变体与绿色荧光蛋白(EGFP)分泌型融合表达载体并在真核细胞中表达。方法:采用PCR法,分别以质粒pIRES2-EGFP和重组质粒pcDNA3.1(+)/uPA为模板,扩增出带BamHⅠ和XbaⅠ酶切位点的EGFP及带NheⅠ和HindⅢ酶切位点的uPA截短体基因片段,先后将EGFP和截短型uPA基因片段克隆到真核表达载体pcDNA3.1(+)上,转入HEK293F细胞,用G418对转染细胞进行加压筛选,通过共聚焦显微镜观察和ELISA方法鉴定表达产物。结果:DNA测序结果显示,uPA不同截短型突变体基因片段与EGFP基因融合的真核表达载体构建成功,共聚焦显微镜观察发现HEK293F细胞中有绿色荧光且定位

  11. US EPA 2012 Air Quality Fused Surface for the Conterminous U.S. Map Service

    Data.gov (United States)

    U.S. Environmental Protection Agency — This web service contains a polygon layer that depicts fused air quality predictions for 2012 for census tracts in the conterminous United States. Fused air quality...

  12. Satellite data compression

    CERN Document Server

    Huang, Bormin

    2011-01-01

    Satellite Data Compression covers recent progress in compression techniques for multispectral, hyperspectral and ultra spectral data. A survey of recent advances in the fields of satellite communications, remote sensing and geographical information systems is included. Satellite Data Compression, contributed by leaders in this field, is the first book available on satellite data compression. It covers onboard compression methodology and hardware developments in several space agencies. Case studies are presented on recent advances in satellite data compression techniques via various prediction-

  13. Trends in communications satellites

    CERN Document Server

    Curtin, Denis J

    1979-01-01

    Trends in Communications Satellites offers a comprehensive look at trends and advances in satellite communications, including experimental ones such as NASA satellites and those jointly developed by France and Germany. The economic aspects of communications satellites are also examined. This book consists of 16 chapters and begins with a discussion on the fundamentals of electrical communications and their application to space communications, including spacecraft, earth stations, and orbit and wavelength utilization. The next section demonstrates how successful commercial satellite communicati

  14. Classification of fused face images using multilayer perceptron neural network

    CERN Document Server

    Bhattacharjee, Debotosh; Nasipuri, Mita; Basu, Dipak Kumar; Kundu, Mahantapas

    2010-01-01

    This paper presents a concept of image pixel fusion of visual and thermal faces, which can significantly improve the overall performance of a face recognition system. Several factors affect face recognition performance including pose variations, facial expression changes, occlusions, and most importantly illumination changes. So, image pixel fusion of thermal and visual images is a solution to overcome the drawbacks present in the individual thermal and visual face images. Fused images are projected into eigenspace and finally classified using a multi-layer perceptron. In the experiments we have used Object Tracking and Classification Beyond Visible Spectrum (OTCBVS) database benchmark thermal and visual face images. Experimental results show that the proposed approach significantly improves the verification and identification performance and the success rate is 95.07%. The main objective of employing fusion is to produce a fused image that provides the most detailed and reliable information. Fusion of multip...

  15. Reliability assessment of reserved water disposal with erodible fuse plug

    Directory of Open Access Journals (Sweden)

    Kosichenko Yuriy Mikhaylovich

    Full Text Available Water disposal constructions are one of the most responsible constructions of reservoir hydrosystem, that’s why the a lot of attention was always paid to the problems of estimating and providing their reliability and safety. The most important function of such objects is providing reliability and safety of other hydraulic constructions and economic assets in afterbay and water head. The authors offer estimation method for reliability and faultless performance of reserved water disposal with erodible fuse plug on low-head water development. In order to estimate the reliability of reserved water disposal with erodible fuse plug the Bayesian treatment was used. The calculation of diagnoses (states of reserved water disposal isoffered in case of diagnostic properties k 1 and k 2. One of the main demands placed onreserved water disposals is erosion of soil plug in case of flood discharge exeedance over the estimated frequency with the full opening of the waste sluice.

  16. Investigate of Mechanical Fuse in Cardan Shaft Using FEM

    OpenAIRE

    Sayed Poorya Rabiei; Reza Azarafza

    2014-01-01

    A Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect drive shaft to driven shaft that cannot be connected directly because of distance or the need to allow for relative movement between them. If overload is applied to cardan shaft, failure can occur in each part of the cardan shaft and maybe some irreparable damage occur to the cardan shaft. Thus it is important to investigate the existence of mechanical fuse in cardan shaft, and this subjcet ...

  17. Fused silica suspension for the VIRGO optics: status and perspectives

    CERN Document Server

    Amico, P; Carbone, L; Gammaitoni, L; Punturo, M; Travasso, F; Vocca, H

    2002-01-01

    Thermal noise in mirror suspension wires is the main limitation of low-frequency sensitivity of interferometric gravitational wave detectors. In order to minimize the pendulum thermal noise, a monolithic design, using a low dissipation material, is proposed for VIRGO. High mechanical Qs and high breaking strengths have been obtained for monolithic fused silica fibres. A low-dissipation and high-strength bonding technique using potassium silicate bonding is proposed.

  18. Fusing Laser and Radar Data for Enhanced Situation Awareness

    OpenAIRE

    Eliasson, Emanuel

    2010-01-01

    With an increasing traffic intensity the demands on vehicular safety is higher than ever before. Active safety systems that have been developed recent years are a response to that. In this master thesis Sensor Fusion is used to combine information from a laser scanner and a microwave radar in order to get more information about the surroundings in front of a vehicle. The Extended Kalman Filter method has been used to fuse the information from the sensors. The process model consists partly of ...

  19. Non-invasive management of fused upper incisors

    OpenAIRE

    Pouran Samimi; Mohammad-Reza Shirban; Farahnaz Arbabzadeh-Zavareh

    2012-01-01

    The union of two different dental sprouts which can happen in any phase of dental development is commonly called fusion. This developmental anomaly may cause clinical problems including esthetic impairment, which are mainly treated by endodontic and surgical treatments. There are a few reports of conservative not invasive treatment of fused incisors teeth through restorative or prosthetic techniques. They are rarely reported in mandibular posterior teeth. This paper presents an unusual case o...

  20. Tetrakis(4-tert-butylphenyl) substituted and fused quinoidal porphyrins

    KAUST Repository

    Zeng, Wangdong

    2012-01-01

    4-tert-Butylphenyl-substituted and fused quinoidal porphyrins 1 and 2 are prepared for the first time. They show (1) intense one-photon absorption in the far-red/near-infrared region, (2) enhanced two-photon absorption compared with aromatic porphyrin monomers, and (3) amphoteric redox behavior. Their geometry and electronic structure are studied by DFT calculations. This journal is © 2012 The Royal Society of Chemistry.

  1. Resistance Training Enhances Skeletal Muscle Innervation Without Modifying the Number of Satellite Cells or their Myofiber Association in Obese Older Adults.

    Science.gov (United States)

    Messi, María Laura; Li, Tao; Wang, Zhong-Min; Marsh, Anthony P; Nicklas, Barbara; Delbono, Osvaldo

    2016-10-01

    Studies in humans and animal models provide compelling evidence for age-related skeletal muscle denervation, which may contribute to muscle fiber atrophy and loss. Skeletal muscle denervation seems relentless; however, long-term, high-intensity physical activity appears to promote muscle reinnervation. Whether 5-month resistance training (RT) enhances skeletal muscle innervation in obese older adults is unknown. This study found that neural cell-adhesion molecule, NCAM+ muscle area decreased with RT and was inversely correlated with muscle strength. NCAM1 and RUNX1 gene transcripts significantly decreased with the intervention. Type I and type II fiber grouping in the vastus lateralis did not change significantly but increases in leg press and knee extensor strength inversely correlated with type I, but not with type II, fiber grouping. RT did not modify the total number of satellite cells, their number per area, or the number associated with specific fiber subtypes or innervated/denervated fibers. Our results suggest that RT has a beneficial impact on skeletal innervation, even when started late in life by sedentary obese older adults.

  2. Ground-based diffusion experiments on liquid Sn-In systems using the shear cell technique of the satellite mission Foton-M1.

    Science.gov (United States)

    Suzuki, Shinsuke; Kraatz, Kurt-Helmut; Frohberg, Günter

    2004-11-01

    This study reported in this paper was aimed at testing the shear cell that was developed for the satellite mission Foton-M1 to measure diffusion coefficients in liquid metals under microgravity (microg)-conditions. Thick Layer diffusion experiments were performed in the system Sn90In10 versus Sn under 1 g-conditions. For this system several microg-diffusion results are available as reference data. This combination provides a low, but sufficiently stable, density layering throughout the entire experiment, which is important to avoid buoyancy-driven convection. The experimental results were corrected for the influences of the shear-induced convection and mixing after the final shearing, both of which are typical for the shear cell technique. As the result, the reproducibility and the reliability of the diffusion coefficients in the ground-based experiments were within the limits of error of microg-data. Based on our results we discuss the necessary conditions to avoid buoyancy-driven convection.

  3. Influence of System Parameters on Fuse Protection Use in Regenerative DC Drives

    Directory of Open Access Journals (Sweden)

    Isa Salman Qamber

    2009-06-01

    Full Text Available Current limiting fuses are widely used to protect the thyristors in DC drive systems. One very important problem is the choice of the correct voltage rating for fuses protecting regenerative DC drives, where many types of fault may occur, which makes fuse protection difficult. In the event of a commutation failure while regenerating, the fuses need to interrupt the loop supplied by the AC and DC voltages acting in series, which is the most difficult case for protection by fuses. In this paper a detailed study of the complete interruption process has been investigated by modeling of arcing process of the fuse protection against the regenerative circuit internal commutation fault. The effect of varying the motor time constant, supply impedance, number of fuses used to clear the fault and DC machine rating on the total transient response is studied. The model of a 200 A fuse is employed in this study. Fuses in series with both the semiconductor devices (F1 and fuses in AC lines (F2 are considered. Comparison was made between arc energy produced for fuses protecting the regenerative circuit if failure occurs, with the arc energy produced in a standard AC test in order to investigate the required voltage rating for the fuse.

  4. Study of Fragmentation Process of Fused Fluxes Using Air

    Directory of Open Access Journals (Sweden)

    Daniel Pérez Pérez

    2011-06-01

    Full Text Available In the paper the fragmentation process with air of fused fluxes is studied by means of a particular treatment of the interaction process between the air and flux fluids starting from physical and mathematical considerations of the collision phenomenon which are the result of the application of Newton's mechanics-classical theory. In the paper is schematized the impact and change of trajectory process of the incandescent fused flux flow because of the air mechanical action provided by a blowpipe and the equations referred to the interaction between the fluids are set. As a result, the equations for estimating the exit angle and the average velocities of the pellets formed are determined whenever the interacting air and flux fluxes are known as well as the incidence angles. From the theory developed the essential parameters of the granulation process with air of fused fluxes, by considering the average diameter of the particles to be obtained for their industrial performance can be estimated.

  5. Sampled MTF of fused fiber optic components and bonded assemblies

    Science.gov (United States)

    Carter, Thomas

    2013-05-01

    Fused fiber optic devices are bundles of glass optical fibers that have been successively bundled and drawn to smaller and smaller sizes, effectively creating a "zero optical path window". Due to the nature of fiber's clad and core design, pixelization or sampling of the resulting image occurs; this sampling fundamentally degrades the image. Degradation of a resulting image caused by an optical system can be quantified by way of its Modulation Transfer Function. However, since fused fiber optic devices first sample then effectively project the original image, they do not meet the Fourier transform's prerequisite conditions of being linear and isoplanatic. Current technologies at SCHOTT Lighting and Imaging have initiated a study to determine methodology for measuring the sampled modulation transfer function of bonded assemblies such as bonded Faceplate-to-OLED and Faceplate-tosensor assemblies. The use of randomly generated targets imaged through the bonded assemblies proved to be a useful tactic. This paper discusses the test methods developed and subsequent measurement of the sampled modulation transfer function of fused fiber optic bundles and bonded assemblies.

  6. Fluid of fused spheres as a model for protein solution

    Directory of Open Access Journals (Sweden)

    M. Kastelic

    2016-03-01

    Full Text Available In this work we examine thermodynamics of fluid with "molecules" represented by two fused hard spheres, decorated by the attractive square-well sites. Interactions between these sites are of short-range and cause association between the fused-sphere particles. The model can be used to study the non-spherical (or dimerized proteins in solution. Thermodynamic quantities of the system are calculated using a modification of Wertheim's thermodynamic perturbation theory and the results compared with new Monte Carlo simulations under isobaric-isothermal conditions. In particular, we are interested in the liquid-liquid phase separation in such systems. The model fluid serves to evaluate the effect of the shape of the molecules, changing from spherical to more elongated (two fused spheres ones. The results indicate that the effect of the non-spherical shape is to reduce the critical density and temperature. This finding is consistent with experimental observations for the antibodies of non-spherical shape.

  7. Expression of cassini, a murine gamma-satellite sequence conserved in evolution, is regulated in normal and malignant hematopoietic cells

    NARCIS (Netherlands)

    Arutyunyan, Anna; Stoddart, Sonia; Yi, Sun-ju; Fei, Fei; Lim, Min; Groffen, Paula; Feldhahn, Niklas; Groffen, John; Heisterkamp, Nora

    2012-01-01

    Background: Acute lymphoblastic leukemia (ALL) cells treated with drugs can become drug-tolerant if co-cultured with protective stromal mouse embryonic fibroblasts (MEFs). Results: We performed transcriptional profiling on these stromal fibroblasts to investigate if they were affected by the

  8. Glucagon like peptide-1-induced glucose metabolism in differentiated human muscle satellite cells is attenuated by hyperglycemia

    DEFF Research Database (Denmark)

    Green, Charlotte J; Henriksen, Tora I; Pedersen, Bente K;

    2012-01-01

    Glucagon like peptide-1 (GLP-1) stimulates insulin secretion from the pancreas but also has extra-pancreatic effects. GLP-1 may stimulate glucose uptake in cultured muscle cells but the mechanism is not clearly defined. Furthermore, while the pancreatic effects of GLP-1 are glucose-dependent......, the glucose-dependency of its extra-pancreatic effects has not been examined....

  9. Intestinal epithelial organoids fuse to form self-organizing tubes in floating collagen gels.

    Science.gov (United States)

    Sachs, Norman; Tsukamoto, Yoshiyuki; Kujala, Pekka; Peters, Peter J; Clevers, Hans

    2017-03-15

    Multiple recent examples highlight how stem cells can self-organize in vitro to establish organoids that closely resemble their in vivo counterparts. Single Lgr5(+) mouse intestinal stem cells can be cultured under defined conditions forming ever-expanding epithelial organoids that retain cell polarization, cell type diversity and anatomical organization of the in vivo epithelium. Although exhibiting a remarkable level of self-organization, the so called 'mini-guts' have a closed cystic structure of microscopic size. Here, we describe a simple protocol to generate macroscopic intestinal tubes from small cystic organoids. Embedding proliferating organoids within a contracting floating collagen gel allows them to align and fuse to generate macroscopic hollow structures ('tubes') that are lined with a simple epithelium containing all major cell types (including functional stem cells) of the small intestine. Cells lining the central contiguous lumen closely resemble the epithelial cells on luminal villi in vivo, whereas buds that protrude from the main tube into the surrounding matrix closely resemble crypts. Thus, the remarkable self-organizing properties of Lgr5(+) stem cells extend beyond the level of the microscopic cystic organoid to the next, macroscopic, level of tube formation. © 2017. Published by The Company of Biologists Ltd.

  10. High-performance fused indium gallium arsenide/silicon photodiode

    Science.gov (United States)

    Kang, Yimin

    Modern long haul, high bit rate fiber-optic communication systems demand photodetectors with high sensitivity. Avalanche photodiodes (APDs) exhibit superior sensitivity performance than other types of photodetectors by virtual of its internal gain mechanism. This dissertation work further advances the APD performance by applying a novel materials integration technique. It is the first successful demonstration of wafer fused InGaAs/Si APDs with low dark current and low noise. APDs generally adopt separate absorption and multiplication (SAM) structure, which allows independent optimization of materials properties in two distinct regions. While the absorption material needs to have high absorption coefficient in the target wavelength range to achieve high quantum efficiency, it is desirable for the multiplication material to have large discrepancy between its electron and hole ionization coefficients to reduce noise. According to these criteria, InGaAs and Si are the ideal materials combination. Wafer fusion is the enabling technique that makes this theoretical ideal an experimental possibility. APDs fabricated on the fused InGaAs/Si wafer with mesa structure exhibit low dark current and low noise. Special device fabrication techniques and high quality wafer fusion reduce dark current to nano ampere level at unity gain, comparable to state-of-the-art commercial III/V APDs. The small excess noise is attributed to the large difference in ionization coefficients between electrons and holes in silicon. Detailed layer structure designs are developed specifically for fused InGaAs/Si APDs based on principles similar to those used in traditional InGaAs/InP APDs. An accurate yet straightforward technique for device structural parameters extraction is also proposed. The extracted results from the fabricated APDs agree with device design parameters. This agreement also confirms that the fusion interface has negligible effect on electric field distributions for devices fabricated

  11. Acute morphine activates satellite glial cells and up-regulates IL-1β in dorsal root ganglia in mice via matrix metalloprotease-9

    Directory of Open Access Journals (Sweden)

    Berta Temugin

    2012-03-01

    Full Text Available Abstract Background Activation of spinal cord glial cells such as microglia and astrocytes has been shown to regulate chronic opioid-induced antinociceptive tolerance and hyperalgesia, due to spinal up-regulation of the proinflammatory cytokines such as interleukin-1 beta (IL-1β. Matrix metalloprotease-9 (MMP-9 has been implicated in IL-1β activation in neuropathic pain. However, it is unclear whether acute opioid treatment can activate glial cells in the peripheral nervous system. We examined acute morphine-induced activation of satellite glial cells (SGCs and up-regulation of IL-1β in dorsal root ganglia (DRGs, and further investigated the involvement of MMP-9 in these opioid-induced peripheral changes. Results Subcutaneous morphine injection (10 mg/kg induced robust peripheral glial responses, as evidenced by increased GFAP expression in DRGs but not in spinal cords. The acute morphine-induced GFAP expression is transient, peaking at 2 h and declining after 3 h. Acute morphine treatment also increased IL-1β immunoreactivity in SGCs and IL-1β activation in DRGs. MMP-9 and GFAP are expressed in DRG neurons and SGCs, respectively. Confocal analysis revealed a close proximity of MMP-9 and GFAP immunostaining. Importantly, morphine-induced DRG up-regulation of GFAP expression and IL-1β activation was abolished after Mmp9 deletion or naloxone pre-treatment. Finally, intrathecal injections of IL-1β-selective siRNA not only reduced DRG IL-1β expression but also prolonged acute morphine-induced analgesia. Conclusions Acute morphine induces opioid receptors- and MMP-9-dependent up-regulation of GFAP expression and IL-1β activation in SGCs of DRGs. MMP-9 could mask and shorten morphine analgesia via peripheral neuron-glial interactions. Targeting peripheral glial activation might prolong acute opioid analgesia.

  12. Myogenic-specific ablation of Fgfr1 impairs FGF2-mediated proliferation of satellite cells at the myofiber niche but does not abolish the capacity for muscle regeneration

    Directory of Open Access Journals (Sweden)

    Zipora eYablonka-Reuveni

    2015-05-01

    Full Text Available Skeletal muscle satellite cells (SCs are Pax7+ myogenic stem cells that reside between the basal lamina and the plasmalemma of the myofiber. In mature muscles, SCs are typically quiescent, but can be activated in response to muscle injury. Depending on the magnitude of tissue trauma, SCs may divide minimally to repair subtle damage within individual myofibers or produce a larger progeny pool that forms new myofibers in cases of overt muscle injury. SC transition through proliferation, differentiation and renewal is governed by the molecular blueprint of the cells as well as by the extracellular milieu at the SC niche. In particular, the role of the fibroblast growth factor (FGF family in regulating SCs during growth and aging is well recognized. Of the several FGFs shown to affect SCs, FGF1, FGF2 and FGF6 proteins have been documented in adult skeletal muscle. These prototypic paracrine FGFs transmit their mitogenic effect through the FGFRs, which are transmembrane tyrosine kinase receptors. Using the mouse model, we show here that of the four FGFRs, only Fgfr1 and Fgfr4 are expressed at relatively high levels in quiescent SCs and their proliferating progeny. To further investigate the role of FGFR1 in adult myogenesis, we have employed a genetic (Cre/loxP approach for myogenic-specific (MyoDCre-driven ablation of Fgfr1. Neither muscle histology nor muscle regeneration following cardiotoxin-induced injury were overtly affected in Fgfr1-ablated mice. This suggests that FGFR1 is not obligatory for SC performance in this acute muscle trauma model, where compensatory growth factor/cytokine regulatory cascades may exist. However, the SC mitogenic response to FGF2 is drastically repressed in isolated myofibers prepared from Fgfr1-ablated mice. Collectively, our study indicates that FGFR1 is important for FGF-mediated proliferation of SCs and its mitogenic role is not compensated by FGFR4 that is also highly expressed in SCs.

  13. A Design of Penetration Ammunition Fuse System Based on Embedded Technology

    Institute of Scientific and Technical Information of China (English)

    LI Qiang; LIU Xiao-ming; XIE Xiao-mei

    2007-01-01

    The hard target smart fuse of penetration ammunition is developing to be smaller,lighter, smarter and multifunction. After analyzing the characteristics of high-g accelerating signals and the penetration algorithms, this paper provides a solution of penetration ammunition fuse system based on embedded technology. This fuse system realizes acquisition of the high-g accelerating signals and uses the appropriate penetration algorithms to process them. The fuse system can not only make the same type of penetration ammunition to attack different kinds of objects accurately, but also meet the other requirements of the function of penetration ammunition fuse system.

  14. Xichang Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    Xichang Satellite Launch Center(XSLC) is mainly for geosynchronous orbit launches. The main purpose of XSLC is to launch spacecraft, such as broadcasting,communications and meteorological satellites, into geo-stationary orbit.Most of the commercial satellite launches of Long March vehicles have been from Xichang Satellite Launch Center. With 20 years' development,XSLC can launch 5 kinds of launch vehicles and send satellites into geostationary orbit and polar orbit. In the future, moon exploration satellites will also be launched from XSLC.

  15. Handbook of satellite applications

    CERN Document Server

    Madry, Scott; Camacho-Lara, Sergio

    2017-01-01

    The first edition of this ground breaking reference work was the most comprehensive reference source available about the key aspects of the satellite applications field. This updated second edition covers the technology, the markets, applications and regulations related to satellite telecommunications, broadcasting and networking—including civilian and military systems; precise satellite navigation and timing networks (i.e. GPS and others); remote sensing and meteorological satellite systems. Created under the auspices of the International Space University based in France, this brand new edition is now expanded to cover new innovative small satellite constellations, new commercial launching systems, innovation in military application satellites and their acquisition, updated appendices, a useful glossary and more.

  16. Cycle life evaluation of 3 Ah Li xMn 2O 4-based lithium-ion secondary cells for low-earth-orbit satellites . I. Full cell results

    Science.gov (United States)

    Brown, Shelley; Ogawa, Keita; Kumeuchi, Youichi; Enomoto, Shinsuke; Uno, Masatoshi; Saito, Hirobumi; Sone, Yoshitsugu; Abraham, Daniel; Lindbergh, Göran

    Lithium-ion batteries are a candidate for the energy storage system onboard low-earth-orbit satellites. Cycle life performance under both orbital and terrestrial conditions must be investigated in order to evaluate any inadvertent effects due to the former and the validity of the latter, with a successful comparison allowing for the extension of terrestrial experimental matrices in order to identify the effects of ageing. The orbital performance of Li xMn 2O 4-based pouch cells onboard the microsatellite REIMEI was monitored and compared with terrestrial experiments, with the cells found to be unaffected by orbital conditions. A lifetime matrix of different cycling depths-of-discharge (DODs: 0, 20, 40%) and temperatures (25, 45 ° C) was undertaken with periodic reference performance tests. A decrease in both the cell end-of-discharge cycling voltage and capacity was accelerated by both higher temperatures and larger DODs. Impedance spectra measured for all ageing conditions indicated that the increase was small, manifested in a state-of-charge dependent increase of the high-frequency semi-circle and a noticeable increase in the high-frequency real axis intercept. An evaluation of the change of both the resistance and capacity of 3 Ah cells led to the development of a potential prognostic state-of-health indicator. The use of elevated temperatures to accelerate cell ageing was validated.

  17. Cycle life evaluation of 3 Ah Li{sub x}Mn{sub 2}O{sub 4}-based lithium-ion secondary cells for low-earth-orbit satellites. I. Full cell results

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Shelley; Lindbergh, Goeran [School of Chemical Science and Engineering, Department of Chemical Engineering and Technology, Teknikringen 42, Royal Institute of Technology, Stockholm SE-100 44 (Sweden); Ogawa, Keita [Advanced Engineering Services Co., Ltd., 1-6-1 Takezono, Tsukuba, Ibaraki 305-0032 (Japan); Kumeuchi, Youichi; Enomoto, Shinsuke [NEC-Tokin Corporation, 1120 Shimokuzawa, Sagamihara, Kanagawa 229-1198 (Japan); Uno, Masatoshi; Saito, Hirobumi; Sone, Yoshitsugu [Japan Aerospace Exploration Agency, Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, Kanagawa 229-8510 (Japan); Abraham, Daniel [Chemical Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)

    2008-12-01

    Lithium-ion batteries are a candidate for the energy storage system onboard low-earth-orbit satellites. Cycle life performance under both orbital and terrestrial conditions must be investigated in order to evaluate any inadvertent effects due to the former and the validity of the latter, with a successful comparison allowing for the extension of terrestrial experimental matrices in order to identify the effects of ageing. The orbital performance of Li{sub x}Mn{sub 2}O{sub 4}-based pouch cells onboard the microsatellite REIMEI was monitored and compared with terrestrial experiments, with the cells found to be unaffected by orbital conditions. A lifetime matrix of different cycling depths-of-discharge (DODs: 0, 20, 40%) and temperatures (25, 45 C) was undertaken with periodic reference performance tests. A decrease in both the cell end-of-discharge cycling voltage and capacity was accelerated by both higher temperatures and larger DODs. Impedance spectra measured for all ageing conditions indicated that the increase was small, manifested in a state-of-charge dependent increase of the high-frequency semi-circle and a noticeable increase in the high-frequency real axis intercept. An evaluation of the change of both the resistance and capacity of 3 Ah cells led to the development of a potential prognostic state-of-health indicator. The use of elevated temperatures to accelerate cell ageing was validated. (author)

  18. Galileo satellite antenna modeling

    Science.gov (United States)

    Steigenberger, Peter; Dach, Rolf; Prange, Lars; Montenbruck, Oliver

    2015-04-01

    The space segment of the European satellite navigation system Galileo currently consists of six satellites. Four of them belong to the first generation of In-Orbit Validation (IOV) satellites whereas the other two are Full Operational Capability (FOC) satellites. High-precision geodetic applications require detailed knowledge about the actual phase center of the satellite and receiver antenna. The deviation of this actual phase center from a well-defined reference point is described by phase center offsets (PCOs) and phase center variations (PCVs). Unfortunately, no public information is available about the Galileo satellite antenna PCOs and PCVs, neither for the IOV, nor the FOC satellites. Therefore, conventional values for the IOV satellite antenna PCOs have been adopted for the Multi-GNSS experiment (MGEX) of the International GNSS Service (IGS). The effect of the PCVs is currently neglected and no PCOs for the FOC satellites are available yet. To overcome this deficiency in GNSS observation modeling, satellite antenna PCOs and PCVs are estimated for the Galileo IOV satellites based on global GNSS tracking data of the MGEX network and additional stations of the legacy IGS network. Two completely independent solutions are computed with the Bernese and Napeos software packages. The PCO and PCV values of the individual satellites are analyzed and the availability of two different solutions allows for an accuracy assessment. The FOC satellites are built by a different manufacturer and are also equipped with another type of antenna panel compared to the IOV satellites. Signal transmission of the first FOC satellite has started in December 2014 and activation of the second satellite is expected for early 2015. Based on the available observations PCO estimates and, optionally PCVs of the FOC satellites will be presented as well. Finally, the impact of the new antenna model on the precision and accuracy of the Galileo orbit determination is analyzed.

  19. Transcriptional networks that regulate muscle stem cell function.

    Science.gov (United States)

    Punch, Vincent G; Jones, Andrew E; Rudnicki, Michael A

    2009-01-01

    Muscle stem cells comprise different populations of stem and progenitor cells found in embryonic and adult tissues. A number of signaling and transcriptional networks are responsible for specification and survival of these cell populations and regulation of their behavior during growth and regeneration. Muscle progenitor cells are mostly derived from the somites of developing embryos, while satellite cells are the progenitor cells responsible for the majority of postnatal growth and adult muscle regeneration. In resting muscle, these stem cells are quiescent, but reenter the cell cycle during their activation, whereby they undergo decisions to self-renew, proliferate, or differentiate and fuse into multinucleated myofibers to repair damaged muscle. Regulation of muscle stem cell activity is under the precise control of a number of extrinsic signaling pathways and active transcriptional networks that dictate their behavior, fate, and regenerative potential. Here, we review the networks responsible for these different aspects of muscle stem cell biology and discuss prevalent parallels between mechanisms regulating the activity of embryonic muscle progenitor cells and adult satellite cells.

  20. Artificial intelligence systems for rainy areas detection and convective cells' delineation for the south shore of Mediterranean Sea during day and nighttime using MSG satellite images

    Science.gov (United States)

    Tebbi, Mohsene Abdelfettah; Haddad, Boualem

    2016-09-01

    The aim of this study is to investigate the potential of cloud classification by means of support vector machines using high resolution images from northern Algeria. The images were taken from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) on board of the Meteosat Second Generation (MSG) satellite. An automatic system was developed to operate during both day and nighttime by following two steps of data processing. The first aims to detect rainy areas in cloud systems, whereas the second delineates convective cells from stratiform ones. A set of 12 spectral parameters was selected to extract information about cloud properties, which are different from day to night. The training and validation steps of this study were performed by in-situ rainfall measurement data, collected during the rainy season of years 2011 and 2012 via automatic rain gauge stations distributed in northern Algeria. Artificial neural networks (ANNs) and support vector machine (SVM) were explored, by combining spectral parameters derived from MSG images. Better performances were obtained by the SVM classifier, in terms of Critical Success Index and Probability of Detection for rainy areas detection (CSI = 0.81, POD = 91%), and also for convective/stratiform delineation (CSI = 0.55, POD = 74%).

  1. Satellite-Delivered Learning.

    Science.gov (United States)

    Arnall, Gail C.

    1987-01-01

    Discusses the application of satellite information delivery to training. Describes a new trend, horizontal programming. Also discusses vertical programming and in-house production of training materials. Lists vendors of satellite-based training. (CH)

  2. GPS Satellite Simulation Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The GPS satellite simulation facility consists of a GPS satellite simulator controlled by either a Silicon Graphics Origin 2000 or PC depending upon unit under test...

  3. China's Recoverable Satellites

    Institute of Scientific and Technical Information of China (English)

    Tang Boehang

    2008-01-01

    @@ By the end of 2006, China had launched 24 recoverable satellites (FSW) in total. Among them, 23 were launched successfully, of which all but one were successfully recovered. Recoverable satellites launched by China are listed in Table 1.

  4. Satellite Tags- Hawaii EEZ

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Satellite tagging was implemented in 2013. Satellite tagging is conducted using a Dan Inject air rifle and deployment arrows designed by Wildlife Computers. Two...

  5. Syntheses of fused tetrahydro--carboline analogues through imide carbonyl activation using BBr3: Evidence for the involvement of fused cyclic -acyliminium ion intermediate

    Indian Academy of Sciences (India)

    Selvaraj Mangalaraj; Jayaraman Selvakumar; Chinnasamy Ramaraj Ramanathan

    2015-05-01

    The fused cyclic -acyliminium ion generated during the imide carbonyl activation reaction of phenethylphthalimide was confirmed by single crystal X-ray diffraction. The Lewis acid assisted imide carbonyl activation methodology was successfully extended to synthesize fused tetrahydro--carboline units from the corresponding -indolylethylimides.

  6. Tree Classification with Fused Mobile Laser Scanning and Hyperspectral Data

    Directory of Open Access Journals (Sweden)

    Juha Hyyppä

    2011-05-01

    Full Text Available Mobile Laser Scanning data were collected simultaneously with hyperspectral data using the Finnish Geodetic Institute Sensei system. The data were tested for tree species classification. The test area was an urban garden in the City of Espoo, Finland. Point clouds representing 168 individual tree specimens of 23 tree species were determined manually. The classification of the trees was done using first only the spatial data from point clouds, then with only the spectral data obtained with a spectrometer, and finally with the combined spatial and hyperspectral data from both sensors. Two classification tests were performed: the separation of coniferous and deciduous trees, and the identification of individual tree species. All determined tree specimens were used in distinguishing coniferous and deciduous trees. A subset of 133 trees and 10 tree species was used in the tree species classification. The best classification results for the fused data were 95.8% for the separation of the coniferous and deciduous classes. The best overall tree species classification succeeded with 83.5% accuracy for the best tested fused data feature combination. The respective results for paired structural features derived from the laser point cloud were 90.5% for the separation of the coniferous and deciduous classes and 65.4% for the species classification. Classification accuracies with paired hyperspectral reflectance value data were 90.5% for the separation of coniferous and deciduous classes and 62.4% for different species. The results are among the first of their kind and they show that mobile collected fused data outperformed single-sensor data in both classification tests and by a significant margin.

  7. Satellite communication engineering

    CERN Document Server

    Kolawole, Michael Olorunfunmi

    2013-01-01

    An undeniably rich and thorough guide to satellite communication engineering, Satellite Communication Engineering, Second Edition presents the fundamentals of information communications systems in a simple and succinct way. This book considers both the engineering aspects of satellite systems as well as the practical issues in the broad field of information transmission. Implementing concepts developed on an intuitive, physical basis and utilizing a combination of applications and performance curves, this book starts off with a progressive foundation in satellite technology, and then moves on

  8. Collaborative Filtering Fusing Label Features Based on SDAE

    DEFF Research Database (Denmark)

    Huo, Huan; Liu, Xiufeng; Zheng, Deyuan

    2017-01-01

    problem, auxiliary information such as labels are utilized. Another approach of recommendation system is content-based model which can’t be directly integrated with CF-based model due to its inherent characteristics. Considering that deep learning algorithms are capable of extracting deep latent features......, this paper applies Stack Denoising Auto Encoder (SDAE) to content-based model and proposes LCF(Deep Learning for Collaborative Filtering) algorithm by combing CF-based model which fuses label features. Experiments on real-world data sets show that DLCF can largely overcome the sparsity problem...

  9. Fused Deposition Technique for Continuous Fiber Reinforced Thermoplastic

    Science.gov (United States)

    Bettini, Paolo; Alitta, Gianluca; Sala, Giuseppe; Di Landro, Luca

    2017-02-01

    A simple technique for the production of continuous fiber reinforced thermoplastic by fused deposition modeling, which involves a common 3D printer with quite limited modifications, is presented. An adequate setting of processing parameters and deposition path allows to obtain components with well-enhanced mechanical characteristics compared to conventional 3D printed items. The most relevant problems related to the simultaneous feeding of fibers and polymer are discussed. The properties of obtained aramid fiber reinforced polylactic acid (PLA) in terms of impregnation quality and of mechanical response are measured.

  10. CHANGE DETECTION BY FUSING ADVANTAGES OF THRESHOLD AND CLUSTERING METHODS

    Directory of Open Access Journals (Sweden)

    M. Tan

    2017-09-01

    Full Text Available In change detection (CD of medium-resolution remote sensing images, the threshold and clustering methods are two kinds of the most popular ones. It is found that the threshold method of the expectation maximum (EM algorithm usually generates a CD map including many false alarms but almost detecting all changes, and the fuzzy local information c-means algorithm (FLICM obtains a homogeneous CD map but with some missed detections. Therefore, we aim to design a framework to improve CD results by fusing the advantages of threshold and clustering methods. Experimental results indicate the effectiveness of the proposed method.

  11. Fused Deposition Technique for Continuous Fiber Reinforced Thermoplastic

    Science.gov (United States)

    Bettini, Paolo; Alitta, Gianluca; Sala, Giuseppe; Di Landro, Luca

    2016-12-01

    A simple technique for the production of continuous fiber reinforced thermoplastic by fused deposition modeling, which involves a common 3D printer with quite limited modifications, is presented. An adequate setting of processing parameters and deposition path allows to obtain components with well-enhanced mechanical characteristics compared to conventional 3D printed items. The most relevant problems related to the simultaneous feeding of fibers and polymer are discussed. The properties of obtained aramid fiber reinforced polylactic acid (PLA) in terms of impregnation quality and of mechanical response are measured.

  12. Nanodrilling of fused silica using nanosecond laser radiation

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, P., E-mail: pierre.lorenz@iom-leipzig.de; Zajadacz, J.; Bayer, L.; Ehrhardt, M.; Zimmer, K.

    2015-10-01

    Graphical abstract: - Highlights: • Low-fluence irradiation of 10 nm Mo on SiO{sub 2} results in the formation of Mo droplets. • High-fluence irradiation of droplets results in the formation of holes in the SiO{sub 2}. • The process allows the formation of randomly distributed and periodic holes. • The randomly distributed hole density ρ{sub h} depends on the fluence (ρ{sub h} ≤ 1.3 μm{sup −2}). • The interaction of the laser beam with Mo/SiO{sub 2} was simulated by FEM. - Abstract: The fast laser drilling of dielectric surfaces with hole diameters in the sub-μm range and a high aspect ratio is a challenge for laser methods. In this study, a novel laser structuring method for the production of randomly and periodically distributed holes in a fused silica surface will be presented using a self-assembling process. A fused silica surface was covered with a 10 nm thick magnetron-sputtered molybdenum film. The metal film was irradiated by a KrF excimer laser (wavelength λ = 248 nm, pulse duration Δt{sub p} = 25 ns) with low laser fluences (Φ < 1 J/cm{sup 2}) and the laser-induced heating resulting in a melting of the metal film and finally in a self-assembled formation of randomly distributed metal droplets due to the surface tension of the metal liquid phase using a top hat beam profile. Furthermore, the usage of a periodically modulated laser beam profile allows the fabrication of periodically distributed droplet pattern. The multi-pulse irradiation of the laser-generated metal droplets with higher laser fluences results in a stepwise evaporation of the metal and in a partial evaporation of the fused silica near the metal droplets. Finally, the laser-induced stepwise evaporation process results in a formation of cone-like holes in the fused silica surface where the resultant holes are dependent on the size of the generated metal droplets and on the laser parameters. The “drilling” process allows the fabrication of holes with a depth up to 1

  13. Platelet satellitism in infectious disease?

    Science.gov (United States)

    Laskaj, Renata; Sikiric, Dubravka; Skerk, Visnja

    2015-01-01

    Background Platelet satellitism is a phenomenon of unknown etiology of aggregating platelets around polymorphonuclear neutrophils and other blood cells which causes pseudothrombocytopenia, visible by microscopic examination of blood smears. It has been observed so far in about a hundred cases in the world. Case subject and methods Our case involves a 73-year-old female patient with a urinary infection. Biochemical serum analysis (CRP, glucose, AST, ALT, ALP, GGT, bilirubin, sodium, potassium, chloride, urea, creatinine) and blood cell count were performed with standard methods on autoanalyzers. Serum protein fractions were examined by electrophoresis and urinalysis with standard methods on autoanalyzer together with microscopic examination of urine sediment. Erythrocyte sedimentation rate, blood culture and urine culture tests were performed with standard methods. Results Due to typical pathological values for bacterial urinary infection, the patient was admitted to the hospital. Blood smear examination revealed phenomenon, which has persisted for three weeks after the disease has been cured. Blood smears with EDTA as an anticoagulant had platelet satellitism whereas the phenomenon was not observed in tubes with different anticoagulants (Na, Li-heparin) and capillary blood. Discussion We hypothesize that satellitism was induced by some immunological mechanism through formation of antibodies which have mediated platelets binding to neutrophil membranes and vice versa. Unfortunately we were unable to determine the putative trigger for this phenomenon. To our knowledge this is the second case of platelet satellitism ever described in Croatia. PMID:26110042

  14. Taiyuan Satellite Launch Center

    Institute of Scientific and Technical Information of China (English)

    LiuJie

    2004-01-01

    There are three major space launch bases in China, the Jiuquan Satellite Launch Center,the Taiyuan Satellite Launch Center and the Xichang Satellite Launch Center. All the three launch centers are located in sparsely populated areas where the terrain is even and the field of vision is broad. Security, transport conditions and the influence of the axial rotation

  15. Geodetic Secor Satellite

    Science.gov (United States)

    1974-06-01

    simple, and had low-power lem. 17 14. Satellite Orientation . The satellite was designed to maintain a constant relationship between the antenna...the same satellite orientation . Further considerations were Th oscillations, however, when higher orbital ranges (500-2500 nautical miles) -, 3 a

  16. TC-2 Satellite Delivered

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    On April 18, 2005, TC-2, the second satellite of Double Star Program (DSP), which was jointly developed by CNSA and ESA, was approved to be delivered to the user after the on-board test and trial operation. The satellite is working well and the performance can meet the user's need. The satellite has collected large amount of valuable scientific data

  17. MEMOS - Mars Environment Monitoring Satellite

    Science.gov (United States)

    Ott, T.; Barabash, S.; von Schéele, F.; Clacey, E.; Pokrupa, N.

    2007-08-01

    The Swedish Institute of Space Physics (IRF) in cooperation with the Swedish Space Corporation (SSC) has conducted first studies on a Mars Environment Monitoring Satellite (MEMOS). The MEMOS microsatellite (mass ELT) Proximity-1 transceiver will autonomously communicate with the parent satellite at inter-satellite ranges 2 kbit/s. The transceiver also implements a coherent transponding mode for orbit determination through two-way Doppler ranging between the parent satellite and MEMOS. In addition ELT is compatible with a future Martian communication and navigation network pursued by NASA, which could be taken advantage of in the future for relaying data or performing ranging via other satellites part of the network. A system design driver for inter-satellite communication at Mars is the high demand of power. This leads to a disk-shape and thus easy to accommodate spacecraft configuration of MEMOS comprising a single sun-pointing solar array favourable in terms of power and spin stability. Multi-junction solar cells, which currently have an efficiency of ~29% under laboratory conditions are a key factor to keep MEMOS solar array area of ~1.15 m2 small compared to the worst case system power requirements of ~105 W. During eclipse periods high-efficient Li-ion batteries (6 x 20 Wh) will ensure power supply. The spacecraft and payload design will incorporate new technology developments such as autonomous navigation, MicroElectroMechanical Systems MEMS, Micro- Opto-ElectroMechanical Systems MOEMS and new materials to achieve low mass at high performance. Thereby it will profit from Swedish developments and heritage in small- / microsatellites like Astrid-2, SMART-1 or the upcoming rendezvous and formation flying demonstration mission PRISMA.

  18. Tsinghua-1 Micro-Satellite Power System Architecture and Design

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The Tsinghua-1 Micro-satellite, the first satellite made by Tsinghua University, was launched in 2000. The power system of the Tsinghua-1 Micro-satellite is one of the most important subsystems. It provides all the power for the satellite platform and the payloads. The power system design includes the regulation,protection and distribution of a 4 × 35 W solar array and 7 Ah NiCd batteries. This subsystem essentially offerstwo buses: an unregulated 14 V bus and a regulated 5 V bus. All distributed power lines to the users areprotected by current tripping switches. In addition, some essential loads, such as the tele-command system,are supplied through fuses. The Tsinghua-1 Micro-satellite power system provides an efficient, flexible,reliable, and cost-effective solution for small satellites in low earth orbit. A better maximum power pointtracking method has been used to increase reliability margins and to increase the efficiency of the powersystem. The power system reliability was evaluated using several different tests, such as the power boardtest, the assembly integrate test (AIT), the electromagnetic compatibility (EMC) test and the thermal vacuumtest (TVT).``

  19. A New Measure for Analyzing and Fusing Sequences of Objects.

    Science.gov (United States)

    Goulermas, John Yannis; Kostopoulos, Alexandros; Mu, Tingting

    2016-05-01

    This work is related to the combinatorial data analysis problem of seriation used for data visualization and exploratory analysis. Seriation re-sequences the data, so that more similar samples or objects appear closer together, whereas dissimilar ones are further apart. Despite the large number of current algorithms to realize such re-sequencing, there has not been a systematic way for analyzing the resulting sequences, comparing them, or fusing them to obtain a single unifying one. We propose a new positional proximity measure that evaluates the similarity of two arbitrary sequences based on their agreement on pairwise positional information of the sequenced objects. Furthermore, we present various statistical properties of this measure as well as its normalized version modeled as an instance of the generalized correlation coefficient. Based on this measure, we define a new procedure for consensus seriation that fuses multiple arbitrary sequences based on a quadratic assignment problem formulation and an efficient way of approximating its solution. We also derive theoretical links with other permutation distance functions and present their associated combinatorial optimization forms for consensus tasks. The utility of the proposed contributions is demonstrated through the comparison and fusion of multiple seriation algorithms we have implemented, using many real-world datasets from different application domains.

  20. Ball driven type MEMS SAD for artillery fuse

    Science.gov (United States)

    Seok, Jin Oh; Jeong, Ji-hun; Eom, Junseong; Lee, Seung S.; Lee, Chun Jae; Ryu, Sung Moon; Oh, Jong Soo

    2017-01-01

    The SAD (safety and arming device) is an indispensable fuse component that ensures safe and reliable performance during the use of ammunition. Because the application of electronic devices for smart munitions is increasing, miniaturization of the SAD has become one of the key issues for next-generation artillery fuses. Based on MEMS technology, various types of miniaturized SADs have been proposed and fabricated. However, none of them have been reported to have been used in actual munitions due to their lack of high impact endurance and complicated explosive train arrangements. In this research, a new MEMS SAD using a ball driven mechanism, is successfully demonstrated based on a UV LIGA (lithography, electroplating and molding) process. Unlike other MEMS SADs, both high impact endurance and simple structure were achieved by using a ball driven mechanism. The simple structural design also simplified the fabrication process and increased the processing yield. The ball driven type MEMS SAD performed successfully under the desired safe and arming conditions of a spin test and showed fine agreement with the FEM simulation result, conducted prior to its fabrication. A field test was also performed with a grenade launcher to evaluate the SAD performance in the firing environment. All 30 of the grenade samples equipped with the proposed MEMS SAD operated successfully under the high-G setback condition.

  1. Potential Linkage of Satellite Cells and Delayed Onset Muscle Soreness%肌卫星细胞与延迟性肌肉酸痛的潜在联系

    Institute of Scientific and Technical Information of China (English)

    赵新娟; 杜海平; 王植元; 张翔

    2015-01-01

    By reviewing related literatures retrieved through the CNKI and Pubmed database. the continuous intensive eccentric exercise may have certain regulation to skeletal muscle satellite cell growth factor which is closely related to repair skeletal muscle damage ; delayed onset muscle soreness sequential timing has certain correlation with skeletal muscle satellite cell proliferation; delayed ache of skeletal muscle special micro environment certain extent to stimulate the secretion of skeletal muscle satellite cell growth factor and promote skeletal muscle sarcomere remodeling.%检索中国知网和Pubmed数据库中相关文献并对其进行综述。持续大强度离心运动可能对与骨骼肌损伤修复密切相关的骨骼肌卫星细胞生长因子具有一定的调节作用;持续大强度离心运动引发的延迟性肌肉酸痛的发生时序与骨骼肌卫星细胞增殖时序存在一定的相关性;延迟性酸痛的骨骼肌特殊微环境一定程度上刺激骨骼肌卫星细胞生长因子的分泌,促进骨骼肌肌节重塑。

  2. Meteorological satellite systems

    CERN Document Server

    Tan, Su-Yin

    2014-01-01

    “Meteorological Satellite Systems” is a primer on weather satellites and their Earth applications. This book reviews historic developments and recent technological advancements in GEO and polar orbiting meteorological satellites. It explores the evolution of these remote sensing technologies and their capabilities to monitor short- and long-term changes in weather patterns in response to climate change. Satellites developed by various countries, such as U.S. meteorological satellites, EUMETSAT, and Russian, Chinese, Japanese and Indian satellite platforms are reviewed. This book also discusses international efforts to coordinate meteorological remote sensing data collection and sharing. This title provides a ready and quick reference for information about meteorological satellites. It serves as a useful tool for a broad audience that includes students, academics, private consultants, engineers, scientists, and teachers.

  3. Theory of geostationary satellites

    CERN Document Server

    Zee, Chong-Hung

    1989-01-01

    Geostationary or equatorial synchronous satellites are a daily reminder of our space efforts during the past two decades. The nightly television satellite weather picture, the intercontinental telecommunications of television transmissions and telephone conversations, and the establishrnent of educational programs in remote regions on Earth are constant reminders of the presence of these satellites. As used here, the term 'geo­ stationary' must be taken loosely because, in the long run, the satellites will not remain 'stationary' with respect to an Earth-fixed reference frame. This results from the fact that these satellites, as is true for all satellites, are incessantly subject to perturbations other than the central-body attraction of the Earth. Among the more predominant pertur­ bations are: the ellipticity of the Earth's equator, the Sun and Moon, and solar radiation pressure. Higher harmonics of the Earth's potential and tidal effects also influence satellite motion, but they are of second­ order whe...

  4. 大鼠骨骼肌卫星细胞的原代培养鉴定和体外分化特点%Study on culture, identification and differentiation of primary rat skeletal muscle satellite cells

    Institute of Scientific and Technical Information of China (English)

    冯永强; 李峥; 褚万立; 郁永辉; 马丽; 柴家科

    2016-01-01

    目的 建立骨骼肌卫星细胞(SMSC)的体外分离、原代培养、鉴定方法,观察细胞的成肌分化特点.方法 采用组织块法结合差速贴壁法获得SMSC.采用免疫荧光和流式细胞仪以Pax7为标志物鉴定分离获得的卫星细胞纯度,用分化培养基诱导SMSC的体外分化,实时定量PCR法检测分化标志基因成肌决定因子(MyoD)和生肌素的mRNA相对表达量.结果 组织块法培养约1周,可见细胞从组织块边缘爬出.经差速贴壁法纯化后,流式细胞仪检测所获得的原代SMSC纯度可达97.6%.细胞体外诱导分化后,MyoD和生肌素基因呈时序性表达.结论 组织块法可成功获得高纯度的SMSC,在体外具有良好的分化能力.%Objective To establish the isolation,culture and identification methods of primary rat skeletal muscle satellite cells (SMSC) and observe its characterization of differentiation in vitro.Methods Skeletal muscle satellite cells were obtained by tissue block culture method in combination with pre-plating techniques,and the purity of these cells was detected by both immunocytochemistry and fluorescence activated cell sorter (FACS) with Pax7 as marker of SMSC.Myogenesis of these cells was induced in differentiation medium and the mRNA expressions of myogenic differentiation gene (MyoD) and Myogenin were determined by Real-time polymerase chain reaction (PCR).Results Cells crawled out from the edge of tissue blocks after 1 week of culture.After purification by pre-plating techniques,more than 97.6% of the cells expressed Pax7,a unique marker of satellite cells.The mRNA of MyoD and Myogenin showed timespecific expression in the myogenesis induction process in vitro.Conclusion Skeletal muscle satellite cells with high purity and strong differentiation ability can be obtained by means of tissue block culture method.

  5. Simultaneous Fusion and Denoising of Panchromatic and Multispectral Satellite Images

    Science.gov (United States)

    Ragheb, Amr M.; Osman, Heba; Abbas, Alaa M.; Elkaffas, Saleh M.; El-Tobely, Tarek A.; Khamis, S.; Elhalawany, Mohamed E.; Nasr, Mohamed E.; Dessouky, Moawad I.; Al-Nuaimy, Waleed; Abd El-Samie, Fathi E.

    2012-12-01

    To identify objects in satellite images, multispectral (MS) images with high spectral resolution and low spatial resolution, and panchromatic (Pan) images with high spatial resolution and low spectral resolution need to be fused. Several fusion methods such as the intensity-hue-saturation (IHS), the discrete wavelet transform, the discrete wavelet frame transform (DWFT), and the principal component analysis have been proposed in recent years to obtain images with both high spectral and spatial resolutions. In this paper, a hybrid fusion method for satellite images comprising both the IHS transform and the DWFT is proposed. This method tries to achieve the highest possible spectral and spatial resolutions with as small distortion in the fused image as possible. A comparison study between the proposed hybrid method and the traditional methods is presented in this paper. Different MS and Pan images from Landsat-5, Spot, Landsat-7, and IKONOS satellites are used in this comparison. The effect of noise on the proposed hybrid fusion method as well as the traditional fusion methods is studied. Experimental results show the superiority of the proposed hybrid method to the traditional methods. The results show also that a wavelet denoising step is required when fusion is performed at low signal-to-noise ratios.

  6. The human desmin promoter drives robust gene expression for skeletal muscle stem cell-mediated gene therapy.

    Science.gov (United States)

    Jonuschies, Jacqueline; Antoniou, Michael; Waddington, Simon; Boldrin, Luisa; Muntoni, Francesco; Thrasher, Adrian; Morgan, Jennifer

    2014-01-01

    Lentiviral vectors (LVs) represent suitable candidates to mediate gene therapy for muscular dystrophies as they infect dividing and non-dividing cells and integrate their genetic material into the host genome, thereby theoretically mediating longterm expression. We evaluated the ability of LVs where a GFP reporter gene was under the control of five different promoters, to transduce and mediate expression in myogenic and non-myogenic cells in vitro and in skeletal muscle fibres and stem (satellite) cells in vivo. We further analysed lentivirally-transduced satellite cell-derived myoblasts following their transplantation into dystrophic, immunodeficient mouse muscles. The spleen focus-forming virus promoter mediated the highest gene expression in all cell types; the CBX3-HNRPA2B1 ubiquitously-acting chromatin opening element (UCOE) promoter was also active in all cells, whereas the human desmin promoter in isolation or fused with UCOE had lower activity in non-muscle cells. Surprisingly, the human skeletal muscle actin promoter was also active in immune cells. The human desmin promoter mediated robust, persistent reporter gene expression in myogenic cells in vitro, and satellite cells and muscle fibres in vivo. The human desmin promoter combined with UCOE did not significantly increase transgene expression. Therefore, our data indicate that the desmin promoter is suitable for the development of therapeutic purposes.

  7. Seismic design or retrofit of buildings with metallic structural fuses by the damage-reduction spectrum

    Science.gov (United States)

    Li, Gang; Jiang, Yi; Zhang, Shuchuan; Zeng, Yan; Li, Qiang

    2015-03-01

    Recently, the structural fuse has become an important issue in the field of earthquake engineering. Due to the trilinearity of the pushover curve of buildings with metallic structural fuses, the mechanism of the structural fuse is investigated through the ductility equation of a single-degree-of-freedom system, and the corresponding damage-reduction spectrum is proposed to design and retrofit buildings. Furthermore, the controlling parameters, the stiffness ratio between the main frame and structural fuse and the ductility factor of the main frame, are parametrically studied, and it is shown that the structural fuse concept can be achieved by specific combinations of the controlling parameters based on the proposed damage-reduction spectrum. Finally, a design example and a retrofit example, variations of real engineering projects after the 2008 Wenchuan earthquake, are provided to demonstrate the effectiveness of the proposed design procedures using buckling restrained braces as the structural fuses.

  8. Prokaryotic expression and characterization of a pea actin isoform (PEAcl) fused to GFP

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shaobin; REN Dongtao; XU Xiaojing; LIU Guoqin

    2004-01-01

    Actins widely exist in eukaryotic cells and play important roles in many living activities. As there are many kinds of actin isoforms in plant cells, it is difficult to purify each actin isoform in sufficient quantities for analyzing its physicochemical properties. In the present study, a pea(Pisum Sativum L.) actin isoform (PEAc1) fused to His-tag at its amino terminus and GFP (green fluorescent protein) at its Carboxyl terminus were expressed in E. Coli in inclusion bodies. The fusion protein (PEAc1-GFP) was highly purified with the yield of above 2 mg/L culture by dissolving inclusions in 8 mol/L urea, renaturing by dialysis in a gradient of urea, and affinity binding to Ni-resin. The purified mono meric PEAc1-GFP could efficiently bind on Dnase Ⅰ and inhibit the latter's enzyme activity. PEAc1-GFP could polymerize into green fluorescent filamentous structures (F-PEAc1-GFP), which could be labeled by TRITC-phalloidin, a specific agent for observing microfilaments. The PEAc1-GFP polymerization curve was identical with that of chicken skeletal muscle actin. The critical concentration for PEAc1-GFP to polymerize into filaments is 0.24 μmol/L. The F-PEAc1-GFP could stimulate myosin Mg-ATPase activity in a protein concentration dependant manner (about 4 folds at1 mg/mL F-PEAc1-GFP). The results above show that the PEAcl fused to GFP retained the assembly characteristic of actin, indicating that gene fusion, prokaryotic expression,denaturation and renaturation, and affinity chromatography is a useful strategy for obtaining plant actin isoform proteins in a large amount.

  9. FOP is a centriolar satellite protein involved in ciliogenesis.

    Directory of Open Access Journals (Sweden)

    Joanna Y Lee

    Full Text Available Centriolar satellites are proteinaceous granules that are often clustered around the centrosome. Although centriolar satellites have been implicated in protein trafficking in relation to the centrosome and cilium, the details of their function and composition remain unknown. FOP (FGFR1 Oncogene Partner is a known centrosome protein with homology to the centriolar satellite proteins FOR20 and OFD1. We find that FOP partially co-localizes with the satellite component PCM1 in a cell cycle-dependent manner, similarly to the satellite and cilium component BBS4. As for BBS4, FOP localization to satellites is cell cycle dependent, with few satellites labeled in G1, when FOP protein levels are lowest, and most labeled in G2. FOP-FGFR1, an oncogenic fusion that causes a form of leukemia called myeloproliferative neoplasm, also localizes to centriolar satellites where it increases tyrosine phosphorylation. Depletion of FOP strongly inhibits primary cilium formation in human RPE-1 cells. These results suggest that FOP is a centriolar satellite cargo protein and, as for several other satellite-associated proteins, is involved in ciliogenesis. Localization of the FOP-FGFR1 fusion kinase to centriolar satellites may be relevant to myeloproliferative neoplasm disease progression.

  10. Potassium currents in human myogenic cells from donors of different ages.

    Science.gov (United States)

    Nurowska, Ewa; Dworakowska, Beata; Kloch, Monika; Sobol, Maria; Dołowy, Krzysztof; Wernig, Anton; Ruzzier, Fabio

    2006-06-01

    Ageing in humans is accompanied by a reduction in the capacity of satellite cells to proliferate and the forming myoblasts to fuse. The processes of myoblast differentiation and fusion are associated with specific changes in the cells electrical properties. We wanted to elucidate the possible effects of ageing on these parameters and performed whole-cell patch-clamp recordings on human myoblasts obtained from biopsies of skeletal muscles from 2-, 48- and 76-year-old donors. First, we found that resting membrane potential on the 4th day of differentiation in vitro is less negative in the older than in the younger cells. Moreover, the oldest cells showed a smaller density of outward and inward potassium currents. More cells from the old and middle-age donors have a low (less than -40 mV) potential of activation for the outward potassium current. We conclude that in human myoblasts biophysical properties of potassium currents change with donor age.

  11. FUSE Observations of Comet C/2001 Q4 (NEAT)

    Science.gov (United States)

    Feldman, P. D.; Weaver, H. A.; Christian, D.; Combi, M. R.; Krasnopolsky, V.; Lisse, C. M.; Mumma, M. J.; Shemansky, D. E.; Stern, S. A.

    2004-11-01

    We report observations of comet C/2001 Q4 (NEAT) with the Far Ultraviolet Spectroscopic Explorer (FUSE) beginning 00:40 UT on 2004 April 24. This was the first moving target observation made by FUSE since the failure of two reaction wheels in December 2001. Spectra were obtained in the 905--1180 Å range at 0.3 Å spectral resolution using the 30'' × 30'' aperture and closely resemble the spectra of three comets observed in 2001 and reported previously. The principal features are the (0,0) bands of the CO Birge-Hopfield systems, atomic lines of \\ion{O}{1} and \\ion{H}{1}, and three lines of the H2 Lyman pumped by solar Lyman-β fluorescence. The CO C - X (0,0) band showed a nearly sinusoidal variation over the 27 hr observation interval with a period of 17.0 hr and a peak to minimum ratio of 1.56. The derived average CO production rate is Q(CO) = 8 × 1027 molecules s-1 which is about 4% that of H2O based on concurrent HST/STIS observations of OH emission. As in the previous observations, only upper limits are found for emission from \\ion{Ar}{1} and N2. A relatively strong feature near 1031.8 Å is most likely the H2 Werner (1,1) Q3 line pumped by solar \\ion{O}{6} and \\ion{N}{3}, as the corresponding lines in the (1,3) and (1,4) bands are also present. There may be evidence for weak \\ion{O}{6} emission at 1031.9 Å, in the wing of the H2 line, and at 1037.6 Å. The roughly two dozen other emissions that were not identified in the earlier spectra are also present in C/2001 Q4 at comparable strength to those in comet C/2001 A2 (LINEAR). As C/2001 A2 had a comparable water production rate to that of C/2001 Q4 at the time of observation, the source(s) of these emissions may be ubiquitous in comets. This work is based on data obtained by the NASA-CNES-CSA FUSE mission operated by The Johns Hopkins University. Financial support was partly provided by NASA contract NAS5-32985.

  12. High-voltage safety fuses for the transition-radiation tracking detector in the ATLAS experiment

    CERN Document Server

    Voronov, S A; Onishchenko, E M; Simakov, A B; Sosnovtsev, V V; Suchkov, S; Sugrobova, T A

    2004-01-01

    A safety fuse has been designed for the electrical protection of gas- filled detectors in the ATLAS experiment at CERN (Geneva, Switzerland). The fuse is a polished lithium niobate plate with a titanium strip of 91-kOmega resistance deposited by the photolithographic technique. The forced blowout time of the fuse is 10-50 ms; whereupon the leakage current through it is less than 1 nA at a 2-kV voltage. The resistance of the fuse case is greater than or equivalent equal' greater than 10**1**2 Omega. Its overall dimensions are 5.8 multiplied by 3.8 multiplied by 2 mm.

  13. Development of Fuses for Protection of Geiger-Mode Avalanche Photodiode Arrays

    Science.gov (United States)

    Grzesik, Michael; Bailey, Robert; Mahan, Joe; Ampe, Jim

    2015-11-01

    Current-limiting fuses composed of Ti/Al/Ni were developed for use in Geiger-mode avalanche photodiode arrays for each individual pixel in the array. The fuses were designed to burn out at ˜4.5 × 10-3 A and maintain post-burnout leakage currents less than 10-7 A at 70 V sustained for several minutes. Experimental fuse data are presented and successful incorporation of the fuses into a 256 × 64 pixel InP-based Geiger-mode avalanche photodiode array is reported.

  14. Optimized condition for etching fused-silica phase gratings with inductively coupled plasma technology.

    Science.gov (United States)

    Wang, Shunquan; Zhou, Changhe; Ru, Huayi; Zhang, Yanyan

    2005-07-20

    Polymer deposition is a serious problem associated with the etching of fused silica by use of inductively coupled plasma (ICP) technology, and it usually prevents further etching. We report an optimized etching condition under which no polymer deposition will occur for etching fused silica with ICP technology. Under the optimized etching condition, surfaces of the fabricated fused silica gratings are smooth and clean. Etch rate of fused silica is relatively high, and it demonstrates a linear relation between etched depth and working time. Results of the diffraction of gratings fabricated under the optimized etching condition match theoretical results well.

  15. Threats to ICF reactor materials: computational simulations of radiation damage induced topological changes in fused silica

    CERN Document Server

    Kubota, A; Stolken, J; Sadigh, B; Reyes, S; Rubia, T D; Latkowski, J F

    2003-01-01

    We have performed molecular dynamics simulations of radiation damage in fused silica. In this study, we discuss the role of successive cascade overlap on the saturation and self-healing of oxygen vacancy defects in the amorphous fused silica network. Furthermore, we present findings on the topological changes in fused silica due to repeated energetic recoil atoms. These topological network modifications consistent with experimental Raman spectroscopic observation on neutron and ion irradiated fused silica are indicators of permanent densification that has also been observed experimentally.

  16. A Fused Maxillary Central Incisor and Its Multidisciplinary Treatment: An 18-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    Lluís Brunet-Llobet

    2014-01-01

    Full Text Available Fused teeth may cause aesthetic, spacing, periodontal, eruption, and caries problems. The present case report describes a 7-year-old boy patient with a chief complaint of unerupted maxillary incisor. Radiographic examination indicated a fused tooth which had two fused roots but two independent root canals. A complex management of a fused tooth is really difficult to standardize. In this case an orthodontic, endodontic, and surgical treatment (intentional replantation allowed the tooth to be retained until 18 years following intervention. Maintenance of the root and alveolar bone in young adults at least until full skeletal maturation should be the main treatment objective.

  17. Integrated Solar Panel Antennas for Cube Satellites

    OpenAIRE

    Mahmoud, Mahmoud N.

    2010-01-01

    This thesis work presents an innovative solution for small satellite antennas by integrating slot antennas and solar cells on the same panel to save small satellite surface real estate and to replace deployed wire antennas for certain operational frequencies. The two main advantages of the proposed antenna are: 1) the antenna does not require an expensive deployment mechanism that is required by dipole antennas; 2) the antenna does not occupy as much valuable surface real estate as patch ante...

  18. Integrated Solar Panel Antennas for Cube Satellites

    OpenAIRE

    Mahmoud, Mahmoud N.

    2010-01-01

    This thesis work presents an innovative solution for small satellite antennas by integrating slot antennas and solar cells on the same panel to save small satellite surface real estate and to replace deployed wire antennas for certain operational frequencies. The two main advantages of the proposed antenna are: 1) the antenna does not require an expensive deployment mechanism that is required by dipole antennas; 2) the antenna does not occupy as much valuable surface real estate as patch ante...

  19. Satellite cells derived from obese humans with type 2 diabetes and differentiated into myocytes in vitro exhibit abnormal response to IL-6.

    Directory of Open Access Journals (Sweden)

    Camilla Scheele

    Full Text Available Obesity and type 2 diabetes are associated with chronically elevated systemic levels of IL-6, a pro-inflammatory cytokine with a role in skeletal muscle metabolism that signals through the IL-6 receptor (IL-6Rα. We hypothesized that skeletal muscle in obesity-associated type 2 diabetes develops a resistance to IL-6. By utilizing western blot analysis, we demonstrate that IL-6Rα protein was down regulated in skeletal muscle biopsies from obese persons with and without type 2 diabetes. To further investigate the status of IL-6 signaling in skeletal muscle in obesity-associated type 2 diabetes, we isolated satellite cells from skeletal muscle of people that were healthy (He, obese (Ob or were obese and had type 2 diabetes (DM, and differentiated them in vitro into myocytes. Down-regulation of IL-6Rα was conserved in Ob myocytes. In addition, acute IL-6 administration for 30, 60 and 120 minutes, resulted in a down-regulation of IL-6Rα protein in Ob myocytes compared to both He myocytes (P<0.05 and DM myocytes (P<0.05. Interestingly, there was a strong time-dependent regulation of IL-6Rα protein in response to IL-6 (P<0.001 in He myocytes, not present in the other groups. Assessing downstream signaling, DM, but not Ob myocytes demonstrated a trend towards an increased protein phosphorylation of STAT3 in DM myocytes (P = 0.067 accompanied by a reduced SOCS3 protein induction (P<0.05, in response to IL-6 administration. Despite this loss of negative control, IL-6 failed to increase AMPKα2 activity and IL-6 mRNA expression in DM myocytes. There was no difference in fusion capacity of myocytes between cell groups. Our data suggest that negative control of IL-6 signaling is increased in myocytes in obesity, whereas a dysfunctional IL-6 signaling is established further downstream of IL-6Rα in DM myocytes, possibly representing a novel mechanism by which skeletal muscle function is compromised in type 2 diabetes.

  20. Note: Discharging fused silica test masses with ionized nitrogen

    Science.gov (United States)

    Ugolini, D.; Funk, Q.; Amen, T.

    2011-04-01

    We have developed a technique for discharging fused silica test masses in a gravitational-wave interferometer with nitrogen ionized by an electron beam. The electrons are produced from a heated filament by thermionic emission in a low-pressure region to avoid contamination and burnout. Some electrons then pass through a small aperture and ionize nitrogen in a higher-pressure region, and this ionized gas is pumped across the test mass surface, neutralizing both polarities of charge. The discharge rate varies exponentially with charge density and filament current, quadratically with filament potential, and has an optimal working pressure of ˜8 mT. Adapting the technique to larger test mass chambers is also discussed.