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Sample records for turkey satellite cell

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

    PubMed

    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. PMID:26769270

  2. Skeletal muscle satellite cells

    NASA Technical Reports Server (NTRS)

    Schultz, E.; McCormick, K. M.

    1994-01-01

    Evidence now suggests that satellite cells constitute a class of myogenic cells that differ distinctly from other embryonic myoblasts. Satellite cells arise from somites and first appear as a distinct myoblast type well before birth. Satellite cells from different muscles cannot be functionally distinguished from one another and are able to provide nuclei to all fibers without regard to phenotype. Thus, it is difficult to ascribe any significant function to establishing or stabilizing fiber type, even during regeneration. Within a muscle, satellite cells exhibit marked heterogeneity with respect to their proliferative behavior. The satellite cell population on a fiber can be partitioned into those that function as stem cells and those which are readily available for fusion. Recent studies have shown that the cells are not simply spindle shaped, but are very diverse in their morphology and have multiple branches emanating from the poles of the cells. This finding is consistent with other studies indicating that the cells have the capacity for extensive migration within, and perhaps between, muscles. Complexity of cell shape usually reflects increased cytoplasmic volume and organelles including a well developed Golgi, and is usually associated with growing postnatal muscle or muscles undergoing some form of induced adaptive change or repair. The appearance of activated satellite cells suggests some function of the cells in the adaptive process through elaboration and secretion of a product. Significant advances have been made in determining the potential secretion products that satellite cells make. The manner in which satellite cell proliferative and fusion behavior is controlled has also been studied. There seems to be little doubt that cellcell coupling is not how satellite cells and myofibers communicate. Rather satellite cell regulation is through a number of potential growth factors that arise from a number of sources. Critical to the understanding of this form

  3. Implementation of National Satellite Based Data Archive (NASABADA) in Turkey

    NASA Astrophysics Data System (ADS)

    Gökdemir, Orhan; Beşer, Özgür; Sürer, Serdar

    2010-05-01

    NASABADA is a unique platform aiming to develop main geographical information system and remote sensing layers that are often used in areas such as: agriculture, forest, climate, hydrology, transportation, meteorology, and energy. Its establishment has started at the second half of the year 2009 in Turkey by Beray Engineering Company, and focused on especially Turkey domain as an individual study area. In general, examples of the satellite-based data-oriented production are usually on global scale and and focuses on a specific satellite. However, the products in NASABADA are consistent with Turkey's geographical conditions, and they are supported by ground information and a time series evaluation as well. Moreover, while developing those algorithms priority is using the national resources and providing a know-how for national information infrastructure. Using different features of satellite data and blending them with ground data to develop and provide the results to the end users of these products is one of the main goals of NASABADA Project. In the first stage of NASABADA, development of 7 products is planned, but the number of products is aimed to be around 20 in the future. The explanation of the pioneering 7 products which their preliminary versions would be published in the near future are as follows: albedo, snow cover, snow water equivalent, cloud, surface temperature, vegetation indices, and daily sun radiation maps. Unique architectural design, algorithms including fuzzy logic and ANN methods have been used for image processing and automatic analysis of large amounts of data on a high-tec file and web servers hardware infrastructure. The final aim of NASABADA is developing a data infrastructure for optimal access to those huge amounts of observational data by end users with tools available to make online processing of data and only gathering required images other than raw data. We discuss the development of the NASABADA data infrastructure, its current

  4. The effect of in vivo and in vitro irradiation (25 Gy) on the subsequent in vitro growth of satellite cells

    NASA Technical Reports Server (NTRS)

    Mozdziak, P. E.; Schultz, E.; Cassens, R. G.

    1996-01-01

    The effect of in vivo and in vitro irradiation on subsequent satellite cell growth, in vitro, was investigated to ascertain the ability of a 25 Gy dose to inhibit satellite cell proliferation. Satellite cells were isolated from the left (irradiated) and right (non-irradiated) Pectoralis thoracicus of two-week-old tom turkeys 16 h (n=3) and seven weeks (n=2) after the left Pectoralis thoracicus had been irradiated (25 Gy). Satellite cells isolated from the irradiated and non-irradiated muscles exhibited similar (P>0.10) in vitro proliferation indicating that a population of satellite cells survived an in vivo dose of 25 Gy. In additional experiments, satellite cell cultures derived from tom turkey Pectoralis thoracicus were irradiated (25 Gy) in vitro. The number of satellite cells did not (P>0.05) increase in irradiated cultures for 134 h following irradiation, while satellite cells in non-irradiated cultures proliferated (P<0.05) over this time. At later time periods, satellite cell number increased (P<0.05) in irradiated cultures indicating that a population of satellite cells survived irradiation. The results of these in vitro experiments suggest that a 25 Gy dose of irradiation does not abolish satellite cell divisions in the turkey Pectoralis thoracicus.

  5. Turkey.

    PubMed

    1988-03-01

    Focus in this discussion of Turkey is on the following: geography; the people; history; government and political conditions; the economy; defense; and relations between the US and Turkey. In 1986, Turkey's population was estimated to be 51.8 million with an annual growth rate of 2.5%. The infant mortality rate is 12.3/1000 with a life expectancy of 62.7 years. Turkey is located partly in Europe and partly in Asia. Since 1950, urban areas have experienced tremendous growth, and squatter dwellings are evident around the cities' edges. About half of Turkey's population live in urban areas. Turkish culture is made up of both the modern and traditional, Ottoman and folkloric, elements. The Republic of Turkey was founded by Mustafa Kemal, subsequently named Ataturk, in 1982 after the collapse of the 600-year-old Ottoman empire. The new republic focused on modernizing and Westernizing the empire's Turkish core -- Anatolia and a small part of Thrace. The 1982 constitution preserves a democratic, secular, parliamentary form of government with a strengthened presidence. It provides for an independent judiciary along with the safeguarding of internationally recognized human rights. The legislative functions are carried out by the unicameral, 450-member GNA. The economy is developing structurally, yet the agricultural sector remains significant and produces cotton, tobacco, grains, fruits, and vegetables. Over half of the labor force are farmers, contributing over 1/5 of the gross domestic product. A significant portion of industry also is involved in processing agricultural products. The period from the mid-1960s to the mid-1970s was the longest sustained period of economic growth and development in modern Turkish history, with annual growth rates of nearly 7%. Oil price increases after 1973 and the concomitant European recession slowed Turkish growth and also revealed major structural deficiencies. The economic crisis worsened in 1979 as oil prices doubled again. The Demirel

  6. Heterogeneity in the muscle satellite cell population

    PubMed Central

    Biressi, Stefano; Rando, Thomas A.

    2010-01-01

    Satellite cells, the adult stem cells responsible for skeletal muscle regeneration, are defined by their location between the basal lamina and the fiber sarcolemma. Increasing evidence suggests that satellite cells represent a heterogeneous population of cells with distinct embryological origin and multiple levels of biochemical and functional diversity. This review focuses on the rich diversity of the satellite cell population based on studies across species. Ultimately, a more complete characterization of the heterogeneity of satellite cells will be essential to understand the functional significance in terms of muscle growth, homeostasis, tissue repair, and aging. PMID:20849971

  7. Old high resolution satellite images for landscape archaeology: case studies from Turkey and Iraq

    NASA Astrophysics Data System (ADS)

    Scardozzi, Giuseppe

    2008-10-01

    The paper concerns the contribution for Landscape Archaeology from satellite images of 1960s and 1970s, very useful when old aerial photographs are scarce. Particularly, the study concerns the panchromatic photos taken by USA reconnaissance satellites from 1963 to 1972, declassified for civil use in 1995 and 2002, that in the last years are very used in the archaeological research; in fact, a lot of these images have an high geometric resolution, about between 2.74 and 1.83 m (Corona KH-4A and KH-4B), and some have a ground resolution about between 1.20 and 0.60 m (Gambit KH-7). These satellite images allow to examine very in detail ancient urban areas and territories that later are changed or partially destroyed; so, it is possible to detect and examine ancient structures, palaeo-environmental elements and archaeological traces of buried features now not visible. The paper presents some exemplificative cases study in Turkey and Iraq, in which the analysis of these images has made a fundamental contribution to the archaeological researches: particularly, for the reconstruction of the urban layout of the ancient city of Hierapolis of Phrygia and for the surveys in its territory, and for the study of the ancient topography of some archaeological sites of Iraq. In this second case, the research is gained in the context of the Iraq Virtual Museum Project; the comparison with recent high resolution satellite images (Ikonos-2, QuickBird-2, WorldView-1) also provide a fundamental tool for monitoring archaeological areas and for an evaluation of the situation after the first and the second Gulf War.

  8. Satellite Cell Heterogeneity in Skeletal Muscle Homeostasis.

    PubMed

    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. PMID:26948993

  9. A webgis supported snow information system with long time satellite data for Turkey

    NASA Astrophysics Data System (ADS)

    Surer, S.; Bolat, K.; Akyurek, Z.

    2012-04-01

    KARBILSIS is an online platform which is developed in order to provide end-users with daily remote sensing snow products for Turkey (www.karbilsis.com). The project has been started as a research activity after an award by Ministry of Science and Technology has been granted to our company. At the first stage of our project MODIS atmospherically corrected reflectance data has been downloaded covering the period of 2000-2011 which makes more than ten years of satellite imagery for Turkey. The archived MODIS data that have been obtained from National Snow and Ice Data Center (NSIDC) is mainly MOD09GA product that includes seven spectral bands. Only the tiles which are covering Turkey have been archived namely 19&20 horizontal and 4&5 vertical ones. In order to provide scientists with a website giving the availability of analysis of snow covered area for long terms based on their area of interests, a fractional snow extent (FSE) product has been generated. For FSE product a normalized difference snow index (NDSI) based algorithm has been developed using daily land surface reflectance values (MOD09GA). In addition to MODIS data, four different Landsat images belonging to different days of snowy period (January, March, and May) have been used during algorithm development taking into account a better representation of different reflectance values of snow which highly varies depending on the accumulation and melting periods. Landsat images were used as reference images. First the Landsat images were orthorectified and mapped to a cartographic projection. Then image segmentation was applied to obtain homogeneous tiles, where the homogeneity is defined as similarity in pixel values. The mean-shift segmentation approach, where each pixel was associated with a significant mode of the joint domain density located in its neighborhood, was applied. After segmentation, the image was classified into snow and no-snow classes with Maximum Likelihood Classification Method. FSE

  10. Activated Muscle Satellite Cells Chase Ghosts.

    PubMed

    Mourikis, Philippos; Relaix, Frédéric

    2016-02-01

    The in vivo behaviors of skeletal muscle stem cells, i.e., satellite cells, during homeostasis and after injury are poorly understood. In this issue of Cell Stem Cell, Webster et al. (2016) now perform a tour de force intravital microscopic analysis of this population, showing that "ghost fiber" remnants act as scaffolds to guide satellite cell divisions after injury. PMID:26849298

  11. Regulation of Satellite Cell Function in Sarcopenia

    PubMed Central

    Alway, Stephen E.; Myers, Matthew J.; Mohamed, Junaith S.

    2014-01-01

    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. PMID:25295003

  12. Regulation of satellite cell function in sarcopenia.

    PubMed

    Alway, Stephen E; Myers, Matthew J; Mohamed, Junaith S

    2014-01-01

    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. PMID:25295003

  13. Antifungal Treatment in Stem Cell Transplantation Centers in Turkey

    PubMed Central

    Akan, Hamdi; Atilla, Erden

    2016-01-01

    Despite the development of various guidelines, the approach to antifungal treatment in stem cell transplantation centers differs according to country or even between centers. This led to the development of another survey that aims to understand the antifungal treatment policies of Turkish stem cell transplantation centers. Although there has been an increasing trend towards the use of diagnostic-based treatments in Turkey in the last few years, empirical treatment is still the main approach. The practices of the stem cell transplantation centers reflect the general trends and controversies in this area, while there is a considerable use of antifungal combination therapy. PMID:25913124

  14. Analysing Regional Land Surface Temperature Changes by Satellite Data, a Case Study of Zonguldak, Turkey

    NASA Astrophysics Data System (ADS)

    Sekertekin, A.; Kutoglu, S.; Kaya, S.; Marangoz, A. M.

    2014-12-01

    In recent years, climate change is one of the most important problems that the ecological system of the world has been encountering. Global warming and climate change have been studied frequently by all disciplines all over the world and Geomatics Engineering also contributes to such studies by means of remote sensing, global positioning system etc. Monitoring Land Surface Temperature (LST) via remote sensing satellites is one of the most important contributions to climatology. LST is an important parameter governing the energy balance on the Earth and there are lots of algorithms to obtain LST by remote sensing techniques. The most commonly used algorithms are split-window algorithm, temperature/emissivity separation method, mono-window algorithm and single channel method. Generally three algorithms are used to obtain LST by using Landsat 5 TM data. These algorithms are radiative transfer equation method, single channel method and mono-window algorithm. Radiative transfer equation method is not applicable because during the satellite pass, atmospheric parameters must be measured in-situ. In this research, mono window algorithm was implemented to Landsat 5 TM image. Besides, meteorological data such as humidity and temperature are used in the algorithm. Acquisition date of the image is 28.08.2011 and our study area is Zonguldak, Turkey. High resolution images are used to investigate the relationships between LST and land cover type. As a result of these analyses, area with vegetation cover has approximately 5 ºC lower temperature than the city center and arid land. Because different surface properties like reinforced concrete construction, green zones and sandbank are all together in city center, LST differs about 10 ºC in the city center. The temperature around some places in thermal power plant region Çatalağzı, is about 5 ºC higher than city center. Sandbank and agricultural areas have highest temperature because of land cover structure. Thanks to this

  15. Satellite cells in human skeletal muscle plasticity

    PubMed Central

    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. PMID:26557092

  16. Determination of horizontal and vertical distribution of Calabrian pine stands in Turkey using SRTM satellite data and GIS.

    PubMed

    Yener, Hakan

    2013-09-01

    Forest areas in Turkey are generally spread on rugged terrain and different elevations. Site factors such as location, elevation from sea level, aspect and slope are effective on an ecosystem's climate, soil characteristics, and hence vegetation. Description of such characteristics will allow for the description of forest ecosystems living on these sites and comparison of such ecosystems to each other. Factors such as elevation, aspect and slope can easily be generated from Digital Elevation Models. In this study, using a digital elevation model obtained from SRTM (Shuttle Radar Topography Mission) satellite data and 1/25,000 scale Forest Information System database, horizontal and vertical distribution of Calabrian pine (Pinus brutia Ten.), which is spatially the most extensively spread needled tree species in Turkey, (to elevation classes) is determined and the generated results (map, table etc.) are presented. PMID:24558804

  17. Using Cell Phones From Satellites

    NASA Technical Reports Server (NTRS)

    Horan, Stephen

    2000-01-01

    During the past several years, an interest has grown in using commercial telecommunications techniques to supply Telemetry and Command (T&C) services. Recently, the National Aeronautics and Space Administration (NASA) Space Operations Management Office (SOMO) has outlined plans to utilize satellite-based telecommunications services to support space operations in space missions over the next several decades. NASA currently obtains the bulk of its telecommunications services for earth-orbiting satellites via the existing government-owned and controlled Space Network (SN) system. This system consists of the constellation of Tracking and Data Relay Satellites (TDRS) in Geostationary Earth Orbit (GEO) and the associated ground terminals and communications intrastructure. This system is valuable and effective for scientific satellites costing over one million dollars. However, for smaller satellites, this system becomes problematic due to the cost of transponders and support infrastructure. The nominal transponders for using the TDRS cannot be obtained for a cost in dollars, and size, weight, or power that the 3 Corner Satellite project can afford. For these types of nanosatellite missions, alternatives that fit the mission cost and satellite profiles are needed. In particular, low-cost access using existing commercial infrastructure would be useful to mission planners. In particular, the ability to obtain low data rate T&C services would be especially valuable. The nanosatellites generally have low T&C requirements and therefore would benefit from using commercial services that could operate in the 2400 bps - 9600 bps range, especially if contact times longer than the 5 - 10 minute ground station passes could be found.

  18. The Benefits and Challenges of Having AN Open and Free Basis Satellite Data Sharing Platform in Turkey: GEZGİN

    NASA Astrophysics Data System (ADS)

    Seda Deveci, Hüsne; Koru, Aziz; Sakarya, Ufuk; Tevrizoğlu, İsmail; Teke, Mustafa; Küpçü, Ramazan; Avenoğlu, Bülent; Demirkesen, Can; Zübeyde Gürbüz, Sevgi; Feray Öztoprak, A.; Açıkgöz, İbrahim Serdar; Hakkı Demirhan, İsmail; Ömer Kozal, Ali; Efendioğlu, Mehmet; Berke, Erdinç; Fehmi Şimşek, F.; Atıl, İlkay; Kaya, Derya; Uçmak, Pınar; Ersöz, Eda; Özen, Hilal

    2016-06-01

    Turkey is a county that experiences rapid socioeconomic development, which, in turn, leads to high urbanization rates due to migration of people from rural to urban areas, many large-scale development projects (e.g. highways, dams, housing and infrastructure), and environmental problems that adversely affect agriculture, such as soil erosion and deforestation. Furthermore, Turkey lies in a region prone to natural disasters, especially earthquakes, landslides, flooding and forest fires. Successfully overcoming these challenges requires continuous monitoring to enable rapid response as well as the development of effective socioeconomic policies. In this regard, space-based earth observation (EO) systems play a critical role in the rapid acquisiton and extraction of crucial information. The first launch of the first Turkish-designed satellite, RASAT, in 2011 led to the wide-spread exploitation of space-based resources by Turkish institutions through the dissemination of EO data on an open and free basis via the GEZGIN internet portal (http://www.gezgin.gov.tr). The push for data sharing was further instigated by the nationally funded project GEOPORTAL ("Satellite Image Processing and Geoportal Development Project") and European Union FP7 project EOPOWER ("Earth Observation for Economic Empowerment"), which strove to create conditions for sustainable economic development through the increased use of Earth observation products and services for environmental applications. In this work, the technical challenges involving processing and preparing raw satellite data for dissemination as well as software design of the GEZGIN Portal will be presented.

  19. Muscle satellite cell heterogeneity and self-renewal

    PubMed Central

    Motohashi, Norio; Asakura, Atsushi

    2014-01-01

    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. PMID:25364710

  20. Satellite Cells and the Muscle Stem Cell Niche

    PubMed Central

    Yin, Hang; Price, Feodor

    2013-01-01

    Adult skeletal muscle in mammals is a stable tissue under normal circumstances but has remarkable ability to repair after injury. Skeletal muscle regeneration is a highly orchestrated process involving the activation of various cellular and molecular responses. As skeletal muscle stem cells, satellite cells play an indispensible role in this process. The self-renewing proliferation of satellite cells not only maintains the stem cell population but also provides numerous myogenic cells, which proliferate, differentiate, fuse, and lead to new myofiber formation and reconstitution of a functional contractile apparatus. The complex behavior of satellite cells during skeletal muscle regeneration is tightly regulated through the dynamic interplay between intrinsic factors within satellite cells and extrinsic factors constituting the muscle stem cell niche/microenvironment. For the last half century, the advance of molecular biology, cell biology, and genetics has greatly improved our understanding of skeletal muscle biology. Here, we review some recent advances, with focuses on functions of satellite cells and their niche during the process of skeletal muscle regeneration. PMID:23303905

  1. Numb-deficient satellite cells have regeneration and proliferation defects.

    PubMed

    George, Rajani M; Biressi, Stefano; Beres, Brian J; Rogers, Erik; Mulia, Amanda K; Allen, Ronald E; Rawls, Alan; Rando, Thomas A; Wilson-Rawls, Jeanne

    2013-11-12

    The adaptor protein Numb has been implicated in the switch between cell proliferation and differentiation made by satellite cells during muscle repair. Using two genetic approaches to ablate Numb, we determined that, in its absence, muscle regeneration in response to injury was impaired. Single myofiber cultures demonstrated a lack of satellite cell proliferation in the absence of Numb, and the proliferation defect was confirmed in satellite cell cultures. Quantitative RT-PCR from Numb-deficient satellite cells demonstrated highly up-regulated expression of p21 and Myostatin, both inhibitors of myoblast proliferation. Transfection with Myostatin-specific siRNA rescued the proliferation defect of Numb-deficient satellite cells. Furthermore, overexpression of Numb in satellite cells inhibited Myostatin expression. These data indicate a unique function for Numb during the initial activation and proliferation of satellite cells in response to muscle injury. PMID:24170859

  2. Forever young: rejuvenating muscle satellite cells

    PubMed Central

    Madaro, Luca; Latella, Lucia

    2015-01-01

    A hallmark of aging is alteration of organismal homeostasis and progressive decline of tissue functions. Alterations of both cell intrinsic functions and regenerative environmental cues contribute to the compromised stem cell activity and reduced regenerative capability occurring in aged muscles. In this perspective, we discuss the new evidence supporting the hypothesis that skeletal muscle stem cells (MuSCs) are intrinsically defective in elderly muscles. In particular, we review three recent papers leading to identify fibroblast growth factor receptor-1, p38 mitogen-activated protein kinase, and p16INK4a as altered signaling in satellite cells from aged mice. These pathways contribute to age-related loss of MuSCs asymmetric polarization, compromised self-renewal capacity, and acquisition of pre-senescent state. The pharmacological manipulation of those networks can open novel strategies to rejuvenate MuSCs and counteract the functional decline of skeletal muscle during aging. PMID:25954192

  3. Sulf1A and HGF regulate satellite-cell growth

    PubMed Central

    Gill, Roop; Hitchins, Laura; Fletcher, Fenella; Dhoot, Gurtej K.

    2010-01-01

    The role of Sulf1A, sulfation and hepatocyte growth factor (HGF) in satellite-cell growth was examined in an in vitro model of dissociated whole skeletal muscle fibres. Pax7-positive quiescent satellite cells express little or no Sulf1A but show rapid re-expression in regenerating myoblasts and myotubes, similar to embryonic muscle and in vitro satellite cells preceding asynchronous MyoD activation. Once activated, Sulf1A and MyoD re-expression persists up to 72 hours in most satellite cells under normal culture conditions and following moderate changes in sulfation, whereas Sulf1A neutralisation by antibodies not only enhances satellite-cell proliferation but also downregulates MyoD and Pax7 expression in a large proportion of the satellite cells. The HGF exposure also induces similar but even more pronounced changes characterised by variable sulfation levels and rapid downregulation of MyoD and Pax7 without myogenin activation in a sub-set of cells. This Pax7-MyoD-myogenin-negative sub-population expresses Sulf1A and Myf5. The transfer of all such satellite-cell progenies onto gelatin-coated-substratum re-activates MyoD and Pax7 gene expression in all cells, thus detecting a distinct sub-population of satellite cells. We conclude that HGF and fine-tuned sulfation levels are major contributory factors controlling satellite-cell growth by regulating the relative activities of actively proliferating and differentiating cells. PMID:20442248

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

    PubMed

    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. PMID:27161598

  5. Advanced Solar Cells for Satellite Power Systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.; Weinberg, Irving

    1994-01-01

    The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

  6. Object-Based Greenhouse Classification from High Resolution Satellite Imagery: a Case Study Antalya-Turkey

    NASA Astrophysics Data System (ADS)

    Coslu, M.; Sonmez, N. K.; Koc-San, D.

    2016-06-01

    Pixel-based classification method is widely used with the purpose of detecting land use and land cover with remote sensing technology. Recently, object-based classification methods have begun to be used as well as pixel-based classification method on high resolution satellite imagery. In the studies conducted, it is indicated that object-based classification method has more successful results than other classification methods. While pixel-based classification method is performed according to the grey value of pixels, object-based classification process is executed by generating imagery segmentation and updatable rule sets. In this study, it was aimed to detect and map the greenhouses from object-based classification method by using high resolution satellite imagery. The study was carried out in the Antalya province which includes greenhouse intensively. The study consists of three main stages including segmentation, classification and accuracy assessment. At the first stage, which was segmentation, the most important part of the object-based imagery analysis; imagery segmentation was generated by using basic spectral bands of high resolution Worldview-2 satellite imagery. At the second stage, applying the nearest neighbour classifier to these generated segments classification process was executed, and a result map of the study area was generated. Finally, accuracy assessments were performed using land studies and digital data of the area. According to the research results, object-based greenhouse classification using high resolution satellite imagery had over 80% accuracy.

  7. Syndecan-4-expressing muscle progenitor cells in the SP engraft as satellite cells during muscle regeneration.

    PubMed

    Tanaka, Kathleen Kelly; Hall, John K; Troy, Andrew A; Cornelison, D D W; Majka, Susan M; Olwin, Bradley B

    2009-03-01

    Skeletal muscle satellite cells, located between the basal lamina and plasma membrane of myofibers, are required for skeletal muscle regeneration. The capacity of satellite cells as well as other cell lineages including mesoangioblasts, mesenchymal stem cells, and side population (SP) cells to contribute to muscle regeneration has complicated the identification of a satellite stem cell. We have characterized a rare subset of the muscle SP that efficiently engrafts into the host satellite cell niche when transplanted into regenerating muscle, providing 75% of the satellite cell population and 30% of the myonuclear population, respectively. These cells are found in the satellite cell position, adhere to isolated myofibers, and spontaneously undergo myogenesis in culture. We propose that this subset of SP cells (satellite-SP cells), characterized by ABCG2, Syndecan-4, and Pax7 expression, constitutes a self-renewing muscle stem cell capable of generating both satellite cells and their myonuclear progeny in vivo. PMID:19265661

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

    PubMed Central

    Li, Bo-jiang; Li, Ping-hua; Huang, Rui-hua; Sun, Wen-xing; Wang, Han; Li, Qi-fa; Chen, Jie; Wu, Wang-jun; Liu, Hong-lin

    2015-01-01

    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. PMID:26104526

  9. Functional Overload Enhances Satellite Cell Properties in Skeletal Muscle.

    PubMed

    Fujimaki, Shin; Machida, Masanao; Wakabayashi, Tamami; Asashima, Makoto; Takemasa, Tohru; Kuwabara, Tomoko

    2016-01-01

    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. PMID:26779264

  10. 3D Timelapse Analysis of Muscle Satellite Cell Motility

    PubMed Central

    Siegel, Ashley L; Atchison, Kevin; Fisher, Kevin E; Davis, George E; Cornelison, DDW

    2009-01-01

    Skeletal muscle repair and regeneration requires the activity of satellite cells, a population of myogenic stem cells scattered throughout the tissue and activated to proliferate and differentiate in response to myotrauma or disease. While it seems likely that satellite cells would need to navigate local muscle tissue to reach damaged areas, relatively little data on such motility exist, and most studies have been with immortalized cell lines. We find that primary satellite cells are significantly more motile than myoblast cell lines, and that adhesion to laminin promotes primary cell motility more than fourfold over other substrates. Using timelapse videomicroscopy to assess satellite cell motility on single living myofibers, we have identified a requirement for the laminin-binding integrin α7β1 in satellite cell motility, as well as a role for hepatocyte growth factor in promoting directional persistence. The extensive migratory behavior of satellite cells resident on muscle fibers suggests caution when determining, based on fixed specimens, whether adjacent cells are daughters from the same mother cell. We also observed more persistent long-term contact between individual satellite cells than has been previously supposed, potential cell-cell attractive and repulsive interactions, and migration between host myofibers. Based on such activity, we assayed for expression of “pathfinding” cues, and found that satellite cells express multiple guidance ligands and receptors. Together, these data suggest that satellite cell migration in vivo may be more extensive than currently thought, and could be regulated by combinations of signals, including adhesive haptotaxis, soluble factors, and guidance cues. Stem Cells 2009;27:2527–2538 PMID:19609936

  11. Satellite cells from dystrophic muscle retain regenerative capacity.

    PubMed

    Boldrin, Luisa; Zammit, Peter S; Morgan, Jennifer E

    2015-01-01

    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. PMID:25460248

  12. Skeletal muscle satellite cells cultured in simulated microgravity

    NASA Technical Reports Server (NTRS)

    Molnar, Greg; Hartzell, Charles R.; Schroedl, Nancy A.; Gonda, Steve R.

    1993-01-01

    Satellite cells are postnatal myoblasts responsible for providing additional nuclei to growing or regenerating muscle cells. Satellite cells retain the capacity to proliferate and differentiate in vitro and therefore provide a useful model to study postnatal muscle development. Most culture systems used to study postnatal muscle development are limited by the two-dimensional (2-D) confines of the culture dish. Limiting proliferation and differentiation of satellite cells in 2-D could potentially limit cell-cell contacts important for developing the level of organization in skeletal muscle obtained in vivo. Culturing satellite cells on microcarrier beads suspended in the High-Aspect-Ratio-Vessel (HARV) designed by NASA provides a low shear, three-dimensional (3-D) environment to study muscle development. Primary cultures established from anterior tibialis muscles of growing rats (approximately 200 gm) were used for all studies and were composed of greater than 75 % satellite cells. Different inoculation densities did not affect the proliferative potential of satellite cells in the HARV. Plating efficiency, proliferation, and glucose utilization were compared between 2-D flat culture and 3-D HARV culture. Plating efficiency (cells attached - cells plated x 100) was similar between the two culture systems. Proliferation was reduced in HARV cultures and this reduction was apparent for both satellite cells and non-satellite cells. Furthermore, reduction in proliferation within the HARV could not be attributed to reduced substrate availability since glucose levels in media from HARV and 2-D cell culture were similar. Morphologically, microcarrier beads within the HARVS were joined together by cells into three-dimensional aggregates composed of greater than 10 beads/aggregate. Aggregation of beads did not occur in the absence of cells. Myotubes were often seen on individual beads or spanning the surface of two beads. In summary, proliferation and differentiation of

  13. 3D timelapse analysis of muscle satellite cell motility.

    PubMed

    Siegel, Ashley L; Atchison, Kevin; Fisher, Kevin E; Davis, George E; Cornelison, D D W

    2009-10-01

    Skeletal muscle repair and regeneration requires the activity of satellite cells, a population of myogenic stem cells scattered throughout the tissue and activated to proliferate and differentiate in response to myotrauma or disease. While it seems likely that satellite cells would need to navigate local muscle tissue to reach damaged areas, relatively little data on such motility exist, and most studies have been with immortalized cell lines. We find that primary satellite cells are significantly more motile than myoblast cell lines, and that adhesion to laminin promotes primary cell motility more than fourfold over other substrates. Using timelapse videomicroscopy to assess satellite cell motility on single living myofibers, we have identified a requirement for the laminin-binding integrin alpha 7 beta 1 in satellite cell motility, as well as a role for hepatocyte growth factor in promoting directional persistence. The extensive migratory behavior of satellite cells resident on muscle fibers suggests caution when determining, based on fixed specimens, whether adjacent cells are daughters from the same mother cell. We also observed more persistent long-term contact between individual satellite cells than has been previously supposed, potential cell-cell attractive and repulsive interactions, and migration between host myofibers. Based on such activity, we assayed for expression of "pathfinding" cues, and found that satellite cells express multiple guidance ligands and receptors. Together, these data suggest that satellite cell migration in vivo may be more extensive than currently thought, and could be regulated by combinations of signals, including adhesive haptotaxis, soluble factors, and guidance cues. PMID:19609936

  14. Intraganglionic interactions between satellite cells and adult sensory neurons.

    PubMed

    Christie, Kimberly; Koshy, Dilip; Cheng, Chu; Guo, GuiFang; Martinez, Jose A; Duraikannu, Arul; Zochodne, Douglas W

    2015-07-01

    Perineuronal satellite cells have an intimate anatomical relationship with sensory neurons that suggests close functional collaboration and mutual support. We examined several facets of this relationship in adult sensory dorsal root ganglia (DRG). Collaboration included the support of process outgrowth by clustering of satellite cells, induction of distal branching behavior by soma signaling, the capacity of satellite cells to respond to distal axon injury of its neighboring neurons, and evidence of direct neuron-satellite cell exchange. In vitro, closely adherent coharvested satellite cells routinely clustered around new outgrowing processes and groups of satellite cells attracted neurite processes. Similar clustering was encountered in the pseudounipolar processes of intact sensory neurons within intact DRG in vivo. While short term exposure of distal growth cones of unselected adult sensory neurons to transient gradients of a PTEN inhibitor had negligible impacts on their behavior, exposure of the soma induced early and substantial growth of their distant neurites and branches, an example of local soma signaling. In turn, satellite cells sensed when distal neuronal axons were injured by enlarging and proliferating. We also observed that satellite cells were capable of internalizing and expressing a neuron fluorochrome label, diamidino yellow, applied remotely to distal injured axons of the neuron and retrogradely transported to dorsal root ganglia sensory neurons. The findings illustrate a robust interaction between intranganglionic neurons and glial cells that involve two way signals, features that may be critical for both regenerative responses and ongoing maintenance. PMID:25979201

  15. Muscle satellite cells from GRMD dystrophic dogs are not phenotypically distinguishable from wild type satellite cells in ex vivo culture

    PubMed Central

    Berg, Zachary; Beffa, Lucas R.; Cook, Daniel P.; Cornelison, D.D.W.

    2013-01-01

    Duchenne muscular dystrophy is a neuromuscular degenerative disorder caused by the absence of dystrophin protein. It is characterized by progressive muscle weakness and cycles of degeneration/regeneration accompanying chronic muscle damage and repair. Canine models of muscular dystrophy, including the dystrophin-deficient golden retriever muscular dystrophy (GRMD), are the most promising animal models for evaluation of potential therapies, however canine-specific molecular tools are limited. In particular, few immune reagents for extracellular epitopes marking canine satellite cells (muscle stem cells) are available. We generated an antibody to the satellite cell marker syndecan-4 that identifies canine satellite cells. We then characterized isolated satellite cells from GRMD muscle and wildtype muscle by several in vitro metrics, and surprisingly found no significant differences between the two populations. We discuss whether accumulated adverse changes in the muscle environment rather than cell-intrinsic defects may be implicated in the eventual failure of satellite cell efficacy in vivo. PMID:21277207

  16. Muscle satellite cells from GRMD dystrophic dogs are not phenotypically distinguishable from wild type satellite cells in ex vivo culture.

    PubMed

    Berg, Zachary; Beffa, Lucas R; Cook, Daniel P; Cornelison, D D W

    2011-04-01

    Duchenne muscular dystrophy is a neuromuscular degenerative disorder caused by the absence of dystrophin protein. It is characterized by progressive muscle weakness and cycles of degeneration/regeneration accompanying chronic muscle damage and repair. Canine models of muscular dystrophy, including the dystrophin-deficient golden retriever muscular dystrophy (GRMD), are the most promising animal models for evaluation of potential therapies, however canine-specific molecular tools are limited. In particular, few immune reagents for extracellular epitopes marking canine satellite cells (muscle stem cells) are available. We generated an antibody to the satellite cell marker syndecan-4 that identifies canine satellite cells. We then characterized isolated satellite cells from GRMD muscle and wildtype muscle by several in vitro metrics, and surprisingly found no significant differences between the two populations. We discuss whether accumulated adverse changes in the muscle environment rather than cell-intrinsic defects may be implicated in the eventual failure of satellite cell efficacy in vivo. PMID:21277207

  17. The potential for archiving and reconstituting valuable strains of turkey (Meleagris gallopavo) using primordial germ cells.

    PubMed

    Wade, Alexander J; French, Nick A; Ireland, Grenham W

    2014-04-01

    Diseases such as avian influenza can destroy turkey flocks, potentially resulting in the loss of valuable or rare genetic material. Consequently, there is an urgent need to develop a means to archive such germplasm. Germline chimeras produced by intravascular transfer of primordial germ cells (PGC) have been reported in other avian species but not turkeys. This study examined the feasibility of both establishing an archive of frozen PGC, and producing germline chimeras by injecting the thawed PGC into host embryos. To meet these aims, the following experiments were performed: (1) PGC identification within turkey embryos; (2) development of an efficient method for isolation of turkey PGC; (3) demonstration that PGC can be cryopreserved, recovered, and retain viability; (4) reinjection into embryos and detection of injected PGC. Primordial germ cells were identified using periodic acid-Schiff reagent and the immunological marker OLP-1. Bloodstream PGC were isolated using Ficoll density gradient centrifugation with PGC recovery peaking at stages 13, 14, and 15 with 32 ± 4.9, 33 ± 6.4, and 26 ± 5.4 PGC recovered, respectively. Primordial germ cells were frozen using Dulbecco's modified Eagle medium, 20% fetal calf serum, and 10% dimethylsulfoxide and demonstrated 90 ± 1.7% viability after 3 mo frozen in liquid nitrogen. Freshly isolated and frozen thawed DiI- and Q-Tracker-labeled PGC repopulated stage 30 gonads after vascular transfer into ex ovo cultured embryos. The DiI-labeled cells repopulated gonads less frequently, with 36 ± 13.2% of gonads containing the DiI-labeled PGC, and 7 ± 3.8% of reinjected PGC reaching the gonads of positive embryos. The Q-tracker-labeled cells were detected more frequently in embryos, with 67 ± 21.1% having positive signals, and 44 ± 4.9% of reinjected Q-tracker-labeled PGC colonized the gonads of positive embryos. This study demonstrated the feasibility of using turkey PGC to archive turkey germplasm from different strains

  18. Human satellite cells have regenerative capacity and are genetically manipulable

    PubMed Central

    Marg, Andreas; Escobar, Helena; Gloy, Sina; Kufeld, Markus; Zacher, Joseph; Spuler, Andreas; Birchmeier, Carmen; Izsvák, Zsuzsanna; Spuler, Simone

    2014-01-01

    Muscle satellite cells promote regeneration and could potentially improve gene delivery for treating muscular dystrophies. Human satellite cells are scarce; therefore, clinical investigation has been limited. We obtained muscle fiber fragments from skeletal muscle biopsy specimens from adult donors aged 20 to 80 years. Fiber fragments were manually dissected, cultured, and evaluated for expression of myogenesis regulator PAX7. PAX7+ satellite cells were activated and proliferated efficiently in culture. Independent of donor age, as few as 2 to 4 PAX7+ satellite cells gave rise to several thousand myoblasts. Transplantation of human muscle fiber fragments into irradiated muscle of immunodeficient mice resulted in robust engraftment, muscle regeneration, and proper homing of human PAX7+ satellite cells to the stem cell niche. Further, we determined that subjecting the human muscle fiber fragments to hypothermic treatment successfully enriches the cultures for PAX7+ cells and improves the efficacy of the transplantation and muscle regeneration. Finally, we successfully altered gene expression in cultured human PAX7+ satellite cells with Sleeping Beauty transposon–mediated nonviral gene transfer, highlighting the potential of this system for use in gene therapy. Together, these results demonstrate the ability to culture and manipulate a rare population of human tissue-specific stem cells and suggest that these PAX7+ satellite cells have potential to restore gene function in muscular dystrophies. PMID:25157816

  19. Satellite cell proliferation in adult skeletal muscle

    NASA Technical Reports Server (NTRS)

    Booth, Frank W. (Inventor); Thomason, Donald B. (Inventor); Morrison, Paul R. (Inventor); Stancel, George M. (Inventor)

    1995-01-01

    Novel methods of retroviral-mediated gene transfer for the in vivo corporation and stable expression of eukaryotic or prokaryotic foreign genes in tissues of living animals is described. More specifically, methods of incorporating foreign genes into mitotically active cells are disclosed. The constitutive and stable expression of E. coli .beta.-galactosidase gene under the promoter control of the Moloney murine leukemia virus long terminal repeat is employed as a particularly preferred embodiment, by way of example, establishes the model upon which the incorporation of a foreign gene into a mitotically-active living eukaryotic tissue is based. Use of the described methods in therapeutic treatments for genetic diseases, such as those muscular degenerative diseases, is also presented. In muscle tissue, the described processes result in genetically-altered satellite cells which proliferate daughter myoblasts which preferentially fuse to form a single undamaged muscle fiber replacing damaged muscle tissue in a treated animal. The retroviral vector, by way of example, includes a dystrophin gene construct for use in treating muscular dystrophy. The present invention also comprises an experimental model utilizable in the study of the physiological regulation of skeletal muscle gene expression in intact animals.

  20. The muscle satellite cell at 50: the formative years

    PubMed Central

    2011-01-01

    In February 1961, Alexander Mauro described a cell 'wedged' between the plasma membrane of the muscle fibre and the surrounding basement membrane. He postulated that it could be a dormant myoblast, poised to repair muscle when needed. In the same month, Bernard Katz also reported a cell in a similar location on muscle spindles, suggesting that it was associated with development and growth of intrafusal muscle fibres. Both Mauro and Katz used the term 'satellite cell' in relation to their discoveries. Today, the muscle satellite cell is widely accepted as the resident stem cell of skeletal muscle, supplying myoblasts for growth, homeostasis and repair. Since 2011 marks both the 50th anniversary of the discovery of the satellite cell, and the launch of Skeletal Muscle, it seems an opportune moment to summarise the seminal events in the history of research into muscle regeneration. We start with the 19th-century pioneers who showed that muscle had a regenerative capacity, through to the descriptions from the mid-20th century of the underlying cellular mechanisms. The journey of the satellite cell from electron microscope curio, to its gradual acceptance as a bona fide myoblast precursor, is then charted: work that provided the foundations for our understanding of the role of the satellite cell. Finally, the rapid progress in the age of molecular biology is briefly discussed, and some ongoing debates on satellite cell function highlighted. PMID:21849021

  1. Satellites

    SciTech Connect

    Burns, J.A.; Matthews, M.S.

    1986-01-01

    The present work is based on a conference: Natural Satellites, Colloquium 77 of the IAU, held at Cornell University from July 5 to 9, 1983. Attention is given to the background and origins of satellites, protosatellite swarms, the tectonics of icy satellites, the physical characteristics of satellite surfaces, and the interactions of planetary magnetospheres with icy satellite surfaces. Other topics include the surface composition of natural satellites, the cratering of planetary satellites, the moon, Io, and Europa. Consideration is also given to Ganymede and Callisto, the satellites of Saturn, small satellites, satellites of Uranus and Neptune, and the Pluto-Charon system.

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

    PubMed Central

    Almeida, Camila F.; Fernandes, Stephanie A.; Ribeiro Junior, Antonio F.; 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. PMID:27042182

  3. Isolation, Culture, Functional Assays, and Immunofluorescence of Myofiber-Associated Satellite Cells.

    PubMed

    Vogler, Thomas O; Gadek, Katherine E; Cadwallader, Adam B; Elston, Tiffany L; Olwin, Bradley B

    2016-01-01

    Adult skeletal muscle stem cells, termed satellite cells, regenerate and repair the functional contractile cells in adult skeletal muscle called myofibers. Satellite cells reside in a niche between the basal lamina and sarcolemma of myofibers. Isolating single myofibers and their associated satellite cells provides a culture system that partially mimics the in vivo environment. We describe methods for isolating and culturing intact individual myofibers and their associated satellite cells from the mouse extensor digitorum longus muscle. Following dissection and isolation of individual myofibers we provide protocols for myofiber transplantation, satellite cell transfection, immune detection of satellite cell antigens, and assays to examine satellite cell self-renewal and proliferation. PMID:27492171

  4. Solar power satellites - Heat engine or solar cells

    NASA Technical Reports Server (NTRS)

    Oman, H.; Gregory, D. L.

    1978-01-01

    A solar power satellite is the energy-converting element of a system that can deliver some 10 GW of power to utilities on the earth's surface. We evaluated heat engines and solar cells for converting sunshine to electric power at the satellite. A potassium Rankine cycle was the best of the heat engines, and 50 microns thick single-crystal silicon cells were the best of the photovoltaic converters. Neither solar cells nor heat engines had a clear advantage when all factors were considered. The potassium-turbine power plant, however, was more difficult to assemble and required a more expensive orbital assembly base. We therefore based our cost analyses on solar-cell energy conversion, concluding that satellite-generated power could be delivered to utilities for around 4 to 5 cents a kWh.

  5. Further Characterisation of the Molecular Signature of Quiescent and Activated Mouse Muscle Satellite Cells

    PubMed Central

    Gnocchi, Viola F.; White, Robert B.; Ono, Yusuke; Ellis, Juliet A.; Zammit, Peter S.

    2009-01-01

    Satellite cells are the resident stem cells of adult skeletal muscle. To date though, there is a paucity of native markers that can be used to easily identify quiescent satellite cells, with Pax7 probably being the best that is currently available. Here we have further characterized a number of recently described satellite cell markers, and also describe novel ones. Caveolin-1, integrin α7 and the calcitonin receptor proved reliable markers for quiescent satellite cells, being expressed by all satellite cells identified with Pax7. These three markers remained expressed as satellite cells were activated and underwent proliferation. The nuclear envelope proteins lamin A/C and emerin, mutations in which underlie Emery-Dreifuss muscular dystrophy, were also expressed in both quiescent and proliferating satellite cells. Conversely, Jagged-1, a Notch ligand, was not expressed in quiescent satellite cells but was induced upon activation. These findings further contribute to defining the molecular signature of muscle satellite cells. PMID:19370151

  6. Effect of Three Centaurea Species Collected from Central Anatolia Region of Turkey on Human Melanoma Cells.

    PubMed

    Russo, Alessandra; Cardile, Venera; Graziano, Adriana C E; Rigano, Daniela; Aktumsek, Abdurrahman; Zengin, Gokhan; Senatore, Felice

    2016-03-01

    Centaurea is the largest genus within the Asteraceae family. Many members of this genus are used in traditional folk medicine, such as Centaurea pulchella used to treat skin problems such as to resolve the abscess. Although biological activities of many Centaurea species have been investigated in different countries and Turkey, cytotoxic effect of C. patula, C. pulchella and C. tchihatcheffii has not been studied yet. Melanoma is one of the most invasive and deadly forms of skin cancer. Therefore, in an ongoing effort to identify new natural anticancer products for the treatment and/or prevention of melanoma cancer, the present study was undertaken to investigate the effect of these Centaurea species, collected from Central Anatolia region of Turkey on cell growth and death in human melanoma cell line, A375.The results revealed that all extracts were able to inhibit, after 48 h of treatment, the growth of cancer cells, that could be related to an overall action of the phenolic compounds present. In fact, C. pulchella, with the highest level of phenolics, showed a major activity followed by C. patula and C. tchihatcheffii. Our data also demonstrate that these natural products induce apoptotic cell death. In conclusion, the study of plant extracts for their cytotoxic and apoptotic properties has shown that medicinal herbs from Centaurea species might have also importance in the prevention and treatment of melanoma. PMID:27169173

  7. Presence of satellite cells in a cardiac rhabdomyoma.

    PubMed

    Trillo, A A; Holleman, I L; White, J T

    1978-05-01

    Cardiac rhabdomyoma is the most common tumour of the heart in infancy and childhood. The clinical presentation, diagnosis and histopathological characteristics have been extensively studied; however, reports on the ultrastructure and histogenesis of this lesion are scanty and inconclusive. The case to be discussed is that of a 10-year-old male who presented with a cardiac rhabdomyoma occupying almost the entire ventricular apex. Ultrastructurally, the rhabdomyoma cells have a central, deeply-indented nucleus surrounded by an admixture of mitochondria and sarcomeres. The remainder of the cytoplasm is occupied by pools of glycogen granules, randomly-orientated myofibrils and small mitochondria. Intercellular junctions are numerous and consist of alternating zonula occludens and macula adherens. Typical satellite cells, sharing a common basement lamina are seen apposed to the rhabdomyoma cells. It is tempting to postulate that the proliferation of the rhabdomyoma cells is accomplished by differentiation of satellite cells, a process known to occur in skeletal muscle. Ultrastructurally, the rhabdomyoma cells are indistinguishable from Purkinje cells. The presence of Purkinje-like cells in ectopic locations within the heart and their association with satellite cells is likely a form of embryological atavism. PMID:669594

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

    PubMed

    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. PMID:27531949

  9. Adult Bone Marrow-Derived Stem Cells in Muscle Connective Tissue and Satellite Cell Niches

    PubMed Central

    Dreyfus, Patrick A.; Chretien, Fabrice; Chazaud, Bénédicte; Kirova, Youlia; Caramelle, Philippe; Garcia, Luis; Butler-Browne, Gillian; Gherardi, Romain K.

    2004-01-01

    Skeletal muscle includes satellite cells, which reside beneath the muscle fiber basal lamina and mainly represent committed myogenic precursor cells, and multipotent stem cells of unknown origin that are present in muscle connective tissue, express the stem cell markers Sca-1 and CD34, and can differentiate into different cell types. We tracked bone marrow (BM)-derived stem cells in both muscle connective tissue and satellite cell niches of irradiated mice transplanted with green fluorescent protein (GFP)-expressing BM cells. An increasing number of GFP+ mononucleated cells, located both inside and outside of the muscle fiber basal lamina, were observed 1, 3, and 6 months after transplantation. Sublaminal cells expressed unambiguous satellite cell markers (M-cadherin, Pax7, NCAM) and fused into scattered GFP+ muscle fibers. In muscle connective tissue there were GFP+ cells located close to blood vessels that expressed the ScaI or CD34 stem-cell antigens. The rate of settlement of extra- and intralaminal compartments by BM-derived cells was compatible with the view that extralaminal cells constitute a reservoir of satellite cells. We conclude that both muscle satellite cells and stem cell marker-expressing cells located in muscle connective tissue can derive from BM in adulthood. PMID:14982831

  10. Determination of burnout levels of nurses working in stem cell transplantation units in Turkey.

    PubMed

    Akkuş, Yeliz; Karacan, Yasemin; Göker, Hakan; Aksu, Salih

    2010-12-01

    Although burnout has been researched widely with regard to nurses working in different settings, until now it has not been investigated among stem cell transplantation unit nurses. This study's aim was to determine the burnout level of 57 nurses who were working in stem cell transplantation units in Turkey. The research instruments that were used included a form of demographic characteristics and the Maslach Burnout Inventory. For all the hematopoietic stem cell transplantation nurses, the mean subscale scores for emotional exhaustion were the highest, followed by personal accomplishment and then depersonalization. The burnout level rose with increasing age and duration on the job. Interventions to reduce burnout are needed at both the administrative and organizational levels. In addition, it is essential to address and prevent the problems that are related to burnout, especially among nurses who work in the same unit for a long time. PMID:21210922

  11. Infrared power cells for satellite power conversion

    NASA Technical Reports Server (NTRS)

    Summers, Christopher J.

    1991-01-01

    An analytical investigation is performed to assess the feasibility of long-wavelength power converters for the direct conversion of IR radiation onto electrical power. Because theses devices need to operate between 5 and 30 um the only material system possible for this application is the HgCdTe system which is currently being developed for IR detectors. Thus solar cell and IR detector theories and technologies are combined. The following subject areas are covered: electronic and optical properties of HgCdTe alloys; optimum device geometry; junction theory; model calculation for homojunction power cell efficiency; and calculation for HgCdTe power cell and power beaming.

  12. Human Muscle Satellite Cells as Targets of Chikungunya Virus Infection

    PubMed Central

    Ozden, Simona; Huerre, Michel; Riviere, Jean-Pierre; Coffey, Lark L.; Afonso, Philippe V.; Mouly, Vincent; de Monredon, Jean; Roger, Jean-Christophe; El Amrani, Mohamed; Yvin, Jean-Luc; Jaffar, Marie-Christine; Frenkiel, Marie-Pascale; Sourisseau, Marion; Schwartz, Olivier; Butler-Browne, Gillian; Desprès, Philippe; Gessain, Antoine; Ceccaldi, Pierre-Emmanuel

    2007-01-01

    Background Chikungunya (CHIK) virus is a mosquito-transmitted alphavirus that causes in humans an acute infection characterised by fever, polyarthralgia, head-ache, and myalgia. Since 2005, the emergence of CHIK virus was associated with an unprecedented magnitude outbreak of CHIK disease in the Indian Ocean. Clinically, this outbreak was characterized by invalidating poly-arthralgia, with myalgia being reported in 97.7% of cases. Since the cellular targets of CHIK virus in humans are unknown, we studied the pathogenic events and targets of CHIK infection in skeletal muscle. Methodology/Principal Findings Immunohistology on muscle biopsies from two CHIK virus-infected patients with myositic syndrome showed that viral antigens were found exclusively inside skeletal muscle progenitor cells (designed as satelllite cells), and not in muscle fibers. To evaluate the ability of CHIK virus to replicate in human satellite cells, we assessed virus infection on primary human muscle cells; viral growth was observed in CHIK virus-infected satellite cells with a cytopathic effect, whereas myotubes were essentially refractory to infection. Conclusions/Significance This report provides new insights into CHIK virus pathogenesis, since it is the first to identify a cellular target of CHIK virus in humans and to report a selective infection of muscle satellite cells by a viral agent in humans. PMID:17565380

  13. Interaction of resident sperm with sperm-storage tubule (SST) epithelial cell microvilli in the turkey breeder hen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Interaction of resident sperm with sperm-storage tubule (SST) epithelial cell microvilli in the turkey breeder hen M.R. Bakst*1 and C. Murphy2, 1Animal Biosciences and Biotechnology Laboratory, 2Electron & Confocal Microscopy Unit, Beltsville Area, ARS, USDA, Beltsville MD Sustained fertilization o...

  14. Sphingosine-1-phosphate receptor 3 influences cell cycle progression in muscle satellite cells

    PubMed Central

    Fortier, Mathieu; Figeac, Nicolas; White, Robert B.; Knopp, Paul; Zammit, Peter S.

    2013-01-01

    Skeletal muscle retains a resident stem cell population called satellite cells, which are mitotically quiescent in mature muscle, but can be activated to produce myoblast progeny for muscle homeostasis, hypertrophy and repair. We have previously shown that satellite cell activation is partially controlled by the bioactive phospholipid, sphingosine-1-phosphate, and that S1P biosynthesis is required for muscle regeneration. Here we investigate the role of sphingosine-1-phosphate receptor 3 (S1PR3) in regulating murine satellite cell function. S1PR3 levels were high in quiescent myogenic cells before falling during entry into cell cycle. Retrovirally-mediated constitutive expression of S1PR3 led to suppressed cell cycle progression in satellite cells, but did not overtly affect the myogenic program. Conversely, satellite cells isolated from S1PR3-null mice exhibited enhanced proliferation ex-vivo. In vivo, acute cardiotoxin-induced muscle regeneration was enhanced in S1PR3-null mice, with bigger muscle fibres compared to control mice. Importantly, genetically deleting S1PR3 in the mdx mouse model of Duchenne muscular dystrophy produced a less severe muscle dystrophic phenotype, than when signalling though S1PR3 was operational. In conclusion, signalling though S1PR3 suppresses cell cycle progression to regulate function in muscle satellite cells. PMID:23911934

  15. Estrogens maintain skeletal muscle and satellite cell functions.

    PubMed

    Kitajima, Yuriko; Ono, Yusuke

    2016-06-01

    Estrogens have crucial roles in an extensive range of physiological functions regulating cellular proliferation and differentiation, development, homeostasis, and metabolism. Therefore, prolonged estrogen insufficiency influences various types of tissues expressing estrogen receptors (ERs). Although ERs are expressed in skeletal muscle and its stem cells, called satellite cells, how prolonged estrogen insufficiency affects their function remains unclear. In this study, we investigated the effect of estrogen reduction on muscle in young ovariectomized (OVX) female mice. We found that reduced estrogens resulted in muscle atrophy in a time-dependent manner. Muscle force generation was reduced in OVX mice. Interestingly, prolonged estrogen insufficiency shifted fiber types toward faster myosin heavy chain isoforms. The number of satellite cells per isolated myofiber was unchanged, while satellite cell expansion, differentiation, and self-renewal were all markedly impaired in OVX mice. Indeed, muscle regeneration was significantly compromised in OVX mice. Taken together, our results demonstrate that estrogens are essential for comprehensively maintaining muscle function with its insufficiency affecting muscle strength and regeneration in young female mice. PMID:27048232

  16. Muscle Satellite Cell Protein Teneurin-4 Regulates Differentiation During Muscle Regeneration.

    PubMed

    Ishii, Kana; Suzuki, Nobuharu; Mabuchi, Yo; Ito, Naoki; Kikura, Naomi; Fukada, So-Ichiro; Okano, Hideyuki; Takeda, Shin'ichi; Akazawa, Chihiro

    2015-10-01

    Satellite cells are maintained in an undifferentiated quiescent state, but during muscle regeneration they acquire an activated stage, and initiate to proliferate and differentiate as myoblasts. The transmembrane protein teneurin-4 (Ten-4) is specifically expressed in the quiescent satellite cells; however, its cellular and molecular functions remain unknown. We therefore aimed to elucidate the function of Ten-4 in muscle satellite cells. In the tibialis anterior (TA) muscle of Ten-4-deficient mice, the number and the size of myofibers, as well as the population of satellite cells, were reduced with/without induction of muscle regeneration. Furthermore, we found an accelerated activation of satellite cells in the regenerated Ten-4-deficient TA muscle. The cell culture analysis using primary satellite cells showed that Ten-4 suppressed the progression of myogenic differentiation. Together, our findings revealed that Ten-4 functions as a crucial player in maintaining the quiescence of muscle satellite cells. PMID:26013034

  17. Ethical and legal aspects of stem cell practices in Turkey: where are we?

    PubMed

    Ozturk Turkmen, H; Arda, B

    2008-12-01

    Advances in medical technology and information have facilitated clinical practices that favourably affect the success rates of treatment for diseases. Regenerative medicine has been the focus of the recent medical agenda, to the extent of fundamentally changing treatment paradigms. Stem cell practices, their efficacy, and associated ethical concerns have been debated intensively in many countries. Stem cell research is carried out along with the treatment of patients. Thus, various groups affected by the practices inevitably participate in the discussions. In addition to discussions based on avoiding any harm, providing benefits and respecting personal autonomy and justice, problems arise owing to the lack of legal regulations for stem cell research and practice. The dimensions of the problems vary in the developing countries, with widespread use of advanced medical technology but with lack of sources allocated for healthcare, dominance of paternalistic physician-patient relationships and failure to achieve a sufficient level of awareness of patients' rights. This article discusses the current situation of stem cell practices within the context of regenerative medicine in Turkey and ethical concerns about some of the legal regulations, such as the Regulation for Umblical Cord Blood Banking and Guidelines for Non-embryonic Stem Cell Study for Non-clinical Purposes directing the research on this issue. PMID:19043103

  18. TAK1 modulates satellite stem cell homeostasis and skeletal muscle repair

    PubMed Central

    Ogura, Yuji; Hindi, Sajedah M.; Sato, Shuichi; Xiong, Guangyan; Akira, Shizuo; Kumar, Ashok

    2015-01-01

    Satellite cells are resident adult stem cells that are required for regeneration of skeletal muscle. However, signalling mechanisms that regulate satellite cell function are less understood. Here we demonstrate that transforming growth factor-β-activated kinase 1 (TAK1) is important in satellite stem cell homeostasis and function. Inactivation of TAK1 in satellite cells inhibits muscle regeneration in adult mice. TAK1 is essential for satellite cell proliferation and its inactivation causes precocious differentiation. Moreover, TAK1-deficient satellite cells exhibit increased oxidative stress and undergo spontaneous cell death, primarily through necroptosis. TAK1 is required for the activation of NF-κB and JNK in satellite cells. Forced activation of NF-κB improves survival and proliferation of TAK1-deficient satellite cells. Furthermore, TAK1-mediated activation of JNK is essential to prevent oxidative stress and precocious differentiation of satellite cells. Collectively, our study suggests that TAK1 is required for maintaining the pool of satellite stem cells and for regenerative myogenesis. PMID:26648529

  19. TAK1 modulates satellite stem cell homeostasis and skeletal muscle repair.

    PubMed

    Ogura, Yuji; Hindi, Sajedah M; Sato, Shuichi; Xiong, Guangyan; Akira, Shizuo; Kumar, Ashok

    2015-01-01

    Satellite cells are resident adult stem cells that are required for regeneration of skeletal muscle. However, signalling mechanisms that regulate satellite cell function are less understood. Here we demonstrate that transforming growth factor-β-activated kinase 1 (TAK1) is important in satellite stem cell homeostasis and function. Inactivation of TAK1 in satellite cells inhibits muscle regeneration in adult mice. TAK1 is essential for satellite cell proliferation and its inactivation causes precocious differentiation. Moreover, TAK1-deficient satellite cells exhibit increased oxidative stress and undergo spontaneous cell death, primarily through necroptosis. TAK1 is required for the activation of NF-κB and JNK in satellite cells. Forced activation of NF-κB improves survival and proliferation of TAK1-deficient satellite cells. Furthermore, TAK1-mediated activation of JNK is essential to prevent oxidative stress and precocious differentiation of satellite cells. Collectively, our study suggests that TAK1 is required for maintaining the pool of satellite stem cells and for regenerative myogenesis. PMID:26648529

  20. Real time of earthquakes prone areas by RST analysis of satellite TIR radiances: results of continuous monitoring over Italy and Turkey regions.

    NASA Astrophysics Data System (ADS)

    Tramutoli, V.; Filizzola, C.; Genzano, N.; Lisi, M.; Paciello, R.; Pergola, N.

    2012-04-01

    Meteorological satellites offering global coverage, continuity of observations and long term time series (starting even 30 years ago) offer a unique possibility not only to learn from the past but also to guarantee continuous monitoring whereas other observation technologies are lacking because too expensive or (like in the case of earthquake precursor studies) or considered useless by decision-makers. Space-time fluctuations of Earth's emitted Thermal Infrared (TIR) radiation have been observed from satellite months to weeks before earthquakes occurrence. The general RST approach has been proposed (since 2001) in order to discriminate normal (i.e. related to the change of natural factor and/or observation conditions) TIR signal fluctuations from anomalous signal transient possibly associated to earthquake occurrence. Since then several earthquakes occurred in Europe, Africa and America have been studied by analyzing decades of satellite observations always using a validation/confutation approach in order to verify the presence/absence of anomalous space-time TIR transients in presence/absence of significant seismic activity. In the framework of PRE-EARTHQUAKES EU-FP7 Project (www.pre-earthquakes.org) , starting from October 2010 (still continuing) RST approach has been applied to MSG/SEVIRI data to generate TIR anomaly maps over Italian peninsula, continuously for all the midnight slots. Since September 2011 the same monitoring activity (still continuing) started for Turkey region. For the first time a similar analysis has been performed in real-time, systematically analyzing TIR anomaly maps in order to identify day by day possible significant (e.g. persistent in the space-time domain) thermal anomalies. During 2011 only in very few cases (1 in Italy in July and 2 in the Turkish region in September and November) the day by day analysis enhanced significant anomalies that in two cases were communicated to the other PRE-EARTHQUAKES partners asking for their

  1. The Satellite Cell in Male and Female, Developing and Adult Mouse Muscle: Distinct Stem Cells for Growth and Regeneration

    PubMed Central

    Neal, Alice; Boldrin, Luisa; Morgan, Jennifer Elizabeth

    2012-01-01

    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. PMID:22662253

  2. Talking Turkey...

    MedlinePlus

    ... page please turn Javascript on. Photo: iStock Talking Turkey… 45 million turkeys are eaten each Thanksgiving, 22 ... more 4 Steps to Making Sense, Safely, of Turkey and "All the Fixin's" The U.S. Food and ...

  3. Regenerative fuel cell study for satellites in GEO orbit

    NASA Technical Reports Server (NTRS)

    Levy, Alexander; Vandine, Leslie L.; Stedman, James K.

    1987-01-01

    Summarized are the results of a 12-month study to identify high performance regenerative hydrogen-oxygen fuel cell concepts for geosynchronous satellite application. Emphasis was placed on concepts with the potential for high energy density (W-hr/lb) and passive means for water and heat management to maximize system reliability. Both polymer membrane and alkaline electrolyte fuel cells were considered, with emphasis on the alkaline cell because of its high performance, advanced state of development, and proven ability to operate in a launch and space environment. Three alkaline system concepts were studied. The first, the integrated design, utilized a configuration in which the fuel cell and electrolysis cells are alternately stacked inside a pressure vessel. Product water is transferred by diffusion during electrolysis and waste heat is conducted through the pressure wall, thus using completely passive means for transfer and control. The second alkaline system, the dedicated design, uses a separate fuel cell and electrolysis stack so that each unit can be optimized in size and weight based on its orbital operating period. The third design was a dual function stack configuration, in which each cell can operate in both fuel cell and electrolysis mode, thus eliminating the need for two separate stacks and associated equipment. Results indicate that using near term technology energy densities between 46 and 52 W-hr/lb can be achieved at efficiencies of 55 percent. System densities of 115 W-hr/lb are contemplated.

  4. Regenerative fuel cell study for satellites in GEO orbit

    NASA Astrophysics Data System (ADS)

    Levy, Alexander; Vandine, Leslie L.; Stedman, James K.

    1987-07-01

    Summarized are the results of a 12-month study to identify high performance regenerative hydrogen-oxygen fuel cell concepts for geosynchronous satellite application. Emphasis was placed on concepts with the potential for high energy density (W-hr/lb) and passive means for water and heat management to maximize system reliability. Both polymer membrane and alkaline electrolyte fuel cells were considered, with emphasis on the alkaline cell because of its high performance, advanced state of development, and proven ability to operate in a launch and space environment. Three alkaline system concepts were studied. The first, the integrated design, utilized a configuration in which the fuel cell and electrolysis cells are alternately stacked inside a pressure vessel. Product water is transferred by diffusion during electrolysis and waste heat is conducted through the pressure wall, thus using completely passive means for transfer and control. The second alkaline system, the dedicated design, uses a separate fuel cell and electrolysis stack so that each unit can be optimized in size and weight based on its orbital operating period. The third design was a dual function stack configuration, in which each cell can operate in both fuel cell and electrolysis mode, thus eliminating the need for two separate stacks and associated equipment. Results indicate that using near term technology energy densities between 46 and 52 W-hr/lb can be achieved at efficiencies of 55 percent. System densities of 115 W-hr/lb are contemplated.

  5. VES16 Li-Ion Cell For Satellite

    NASA Astrophysics Data System (ADS)

    Remy, S.; Prevot, D.; Reulier, D.; Vigier, F., , Dr.

    2011-10-01

    At a period when LEO satellite market is growing, as well as mission life time requirements, Saft has designed a new Li-ion cell aiming to answer those demanding requirements. This development is conducted with the support and partnership of CNES French agency. This VES16 cell combines benefits and heritage of low capacity MPS Li-ion cells, and advantages of Nickel oxide base Li-ion chemistry of VES100-140-180 cells. After a period of cycling evaluation of the cell with slight electrochemistry differences, an optimized cell design has been frozen and is submitted to a large qualification plan, including characterisations, environmental tests, and life time demonstrations. This paper presents the main BOL characteristics and performances achieved during the qualification program, including electrical, thermal and mechanical characterisations. It will also detail the expected lifetime data, and the key results obtained on VES16 cell in LEO mission cycling configuration. A specific paragraph also includes results in GEO cycling configuration, to highlight that the cell can be also proposed on geostationary spacecraft.

  6. Satellite cells, connective tissue fibroblasts and their interactions are crucial for muscle regeneration

    PubMed Central

    Murphy, Malea M.; Lawson, Jennifer A.; Mathew, Sam J.; Hutcheson, David A.; Kardon, Gabrielle

    2011-01-01

    Muscle regeneration requires the coordinated interaction of multiple cell types. Satellite cells have been implicated as the primary stem cell responsible for regenerating muscle, yet the necessity of these cells for regeneration has not been tested. Connective tissue fibroblasts also are likely to play a role in regeneration, as connective tissue fibrosis is a hallmark of regenerating muscle. However, the lack of molecular markers for these fibroblasts has precluded an investigation of their role. Using Tcf4, a newly identified fibroblast marker, and Pax7, a satellite cell marker, we found that after injury satellite cells and fibroblasts rapidly proliferate in close proximity to one another. To test the role of satellite cells and fibroblasts in muscle regeneration in vivo, we created Pax7CreERT2 and Tcf4CreERT2 mice and crossed these to R26RDTA mice to genetically ablate satellite cells and fibroblasts. Ablation of satellite cells resulted in a complete loss of regenerated muscle, as well as misregulation of fibroblasts and a dramatic increase in connective tissue. Ablation of fibroblasts altered the dynamics of satellite cells, leading to premature satellite cell differentiation, depletion of the early pool of satellite cells, and smaller regenerated myofibers. Thus, we provide direct, genetic evidence that satellite cells are required for muscle regeneration and also identify resident fibroblasts as a novel and vital component of the niche regulating satellite cell expansion during regeneration. Furthermore, we demonstrate that reciprocal interactions between fibroblasts and satellite cells contribute significantly to efficient, effective muscle regeneration. PMID:21828091

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

    PubMed Central

    2012-01-01

    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. PMID:23046558

  8. Identification and characterization of a non-satellite cell muscle resident progenitor during postnatal development.

    PubMed

    Mitchell, Kathryn J; Pannérec, Alice; Cadot, Bruno; Parlakian, Ara; Besson, Vanessa; Gomes, Edgar R; Marazzi, Giovanna; Sassoon, David A

    2010-03-01

    Satellite cells are resident myogenic progenitors in postnatal skeletal muscle involved in muscle postnatal growth and adult regenerative capacity. Here, we identify and describe a population of muscle-resident stem cells, which are located in the interstitium, that express the cell stress mediator PW1 but do not express other markers of muscle stem cells such as Pax7. PW1(+)/Pax7(-) interstitial cells (PICs) are myogenic in vitro and efficiently contribute to skeletal muscle regeneration in vivo as well as generating satellite cells and PICs. Whereas Pax7 mutant satellite cells show robust myogenic potential, Pax7 mutant PICs are unable to participate in myogenesis and accumulate during postnatal growth. Furthermore, we found that PICs are not derived from a satellite cell lineage. Taken together, our findings uncover a new and anatomically identifiable population of muscle progenitors and define a key role for Pax7 in a non-satellite cell population during postnatal muscle growth. PMID:20118923

  9. Effect of yeast cell product (CitriStim) supplementation on turkey performance and intestinal immune cell parameters during an experimental lipopolysaccharide injection.

    PubMed

    Shanmugasundaram, Revathi; Sifri, Mamduh; Jeyabalan, Ramesh; Selvaraj, Ramesh K

    2014-11-01

    An experiment was conducted to identify the effect of whole yeast cell product supplementation in turkeys following an experimental inflammatory challenge. A total of 105 one-day-old turkey tom poults were fed basal diets supplemented with 0, 0.1, and 0.2% whole yeast cell product (CitriStim, ADM, Quincy, IL). At 6 wk of age and 16 wk of age, turkeys were injected with lipopolysaccharide (LPS) at 0 or 0.25 mg/kg of BW in a 3 × 2 factorial arrangement. BW gain (P = 0.31) and feed conversion ratio (P = 0.53; 3.13, 2.94, and 2.98 for the 0, 0.10, and 0.20% CitriStim treatments, respectively) at 15 wk of age were not significantly affected by the treatment diets. Yeast cell wall product supplementation had no effect on growth in control-injected turkeys but decreased growth in LPS-injected turkeys (yeast × LPS, P < 0.05). Splenic macrophages from birds fed whole yeast cell product and injected with LPS produced higher (P < 0.01) nitric oxide than the control group injected with LPS at both 6 and 16 wk of age. At 6 and 16 wk of age, birds injected with LPS (P < 0.01; P < 0.01) and supplemented with whole yeast cell product (P = 0.05; P = 0.10) showed increased IL-1 mRNA amounts in cecal tonsils. In birds not injected with LPS, whole yeast cell supplementation increased regulatory T cell percentage and IL-10 mRNA amounts, whereas in birds injected with LPS, whole yeast cell supplementation decreased IL-10 mRNA amounts at both 6 (P < 0.01) and 16 wk (P = 0.01) of age in cecal tonsils. Whole yeast cell product supplementation increased Lactobacillus (P < 0.01 and P = 0.01) and Bifidobacteria (P < 0.01 and P = 0.01) population at 6 and 16 wk of age. In conclusion, the effect of feeding whole yeast cell product on turkeys was dependent on the inflammatory status of the bird. PMID:25239535

  10. Skeletal Muscle Satellite Cells: Background and Methods for Isolation and Analysis in a Primary Culture System

    PubMed Central

    Danoviz, Maria Elena; Yablonka-Reuveni, Zipora

    2012-01-01

    Summary Repair of adult skeletal muscle depends on satellite cells, myogenic stem cells located between the basal lamina and the plasmalemma of the myofiber. Standardized protocols for the isolation and culture of satellite cells are key tools for understanding cell autonomous and extrinsic factors that regulate their performance. Knowledge gained from such studies can contribute important insights to developing strategies for the improvement of muscle repair following trauma and in muscle wasting disorders. This chapter provides an introduction to satellite cell biology and further describes the basic protocol used in our laboratory to isolate and culture satellite cells from adult skeletal muscle. The cell culture conditions detailed herein support proliferation and differentiation of satellite cell progeny and the development of reserve cells, which are thought to reflect the in vivo self-renewal ability of satellite cells. Additionally, this chapter describes our standard immunostaining protocol that allows the characterization of satellite cell progeny by the temporal expression of characteristic transcription factors and structural proteins associated with different stages of myogenic progression. While emphasis is given here to the isolation and characterization of satellite cells from mouse hindlimb muscles, the protocols are suitable for other muscle types (such as diaphragm and extraocular muscles) and for muscles from other species, including chicken and rat. Altogether, the basic protocols described are straightforward and facilitate the study of diverse aspects of skeletal muscle stem cells. PMID:22130829

  11. Progenitors of skeletal muscle satellite cells express the muscle determination gene, MyoD

    PubMed Central

    Kanisicak, Onur; Mendez, Julio J.; Yamamoto, Shoko; Yamamoto, Masakazu; Goldhamer, David J.

    2009-01-01

    Satellite cells are tissue-specific stem cells responsible for skeletal muscle growth and regeneration. Although satellite cells were identified almost 50 years ago, the identity of progenitor populations from which they derive remains controversial. We developed MyoDiCre knockin mice, and used Cre/lox lineage analysis to determine whether satellite cell progenitors express MyoD, a marker of myogenic commitment. Recombination status of satellite cells was determined by confocal microscopy of isolated muscle fibers and by electron microscopic observation of muscle tissue fixed immediately following isolation, using R26R-EYFP and R26R (β-gal) reporter mice, respectively. We show that essentially all adult satellite cells associated with limb and body wall musculature, as well as the diaphragm and extraocular muscles, originate from MyoD+ progenitors. Neonatal satellite cells were Cre-recombined, but only a small minority exhibited ongoing Cre expression, indicating that most satellite cells had expressed MyoD prenatally. We also show that satellite cell development in MyoD-null mice is not due to functional compensation by MyoD non-expressing lineages. The results suggest that satellite cells are derived from committed myogenic progenitors, irrespective of the anatomical location, embryological origin, or physiological properties of associated musculature. PMID:19464281

  12. Invited Review: Extrinsic regulation of domestic animal-derived myogenic satellite cells II

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The existence of myogenic satellite cells was reported some forty-seven years ago, and, since that time, satellite cell research has flourished. So much new information is generated (daily) on these cells that it can be difficult for individuals to keep abreast of important issues related to the act...

  13. BRE facilitates skeletal muscle regeneration by promoting satellite cell motility and differentiation

    PubMed Central

    Xiao, Lihai; Lee, Kenneth Ka Ho

    2016-01-01

    ABSTRACT The function of the Bre gene in satellite cells was investigated during skeletal muscle regeneration. The tibialis anterior leg muscle was experimentally injured in Bre knockout mutant (BRE-KO) mice. It was established that the accompanying muscle regeneration was impaired as compared with their normal wild-type counterparts (BRE-WT). There were significantly fewer pax7+ satellite cells and smaller newly formed myofibers present in the injury sites of BRE-KO mice. Bre was required for satellite cell fusion and myofiber formation. The cell fusion index and average length of newly-formed BRE-KO myofibers were found to be significantly reduced as compared with BRE-WT myofibers. It is well established that satellite cells are highly invasive which confers on them the homing ability to reach the muscle injury sites. Hence, we tracked the migratory behavior of these cells using time-lapse microscopy. Image analysis revealed no difference in directionality of movement between BRE-KO and BRE-WT satellite cells but there was a significant decrease in the velocity of BRE-KO cell movement. Moreover, chemotactic migration assays indicated that BRE-KO satellite cells were significantly less responsive to chemoattractant SDF-1α than BRE-WT satellite cells. We also established that BRE normally protects CXCR4 from SDF-1α-induced degradation. In sum, BRE facilitates skeletal muscle regeneration by enhancing satellite cell motility, homing and fusion. PMID:26740569

  14. Prevalence of beta-thalassemia and sickle cell anemia trait in premarital screening in Konya urban area, Turkey.

    PubMed

    Guler, Ekrem; Caliskan, Umran; UcarAlbayrak, Canan; Karacan, Mehmet

    2007-11-01

    Thalassemias and sickle cell anemia (SCA) are common disease in Turkey. To determine the prevalence of beta-thalassemia and SCA traits in Konya urban area of Turkey, all couples applied for marriage procedures were screened. Screening tests included complete blood count and quantitation of hemoglobin for both partners. The subjects were considered to have the beta-thalassemia trait if they had a mean corpuscular volume of less than 80 fL and/or a mean corpuscular hemoglobin level of less than 27 pg and a hemoglobin A2 level of more than 3.2% or a hemoglobin F level of more than 2%. Subjects were considered to have an SCA trait if they were positive for sickle hemoglobin. During the study, premarital screening of hemoglobinopathies was evaluated retrospectively in 72,918 subjects; the thalassemia trait was detected in 1465 subjects (2%), and the SCA trait was detected in 37 subjects (0.05%). Of the carriers of the beta-thalassemia trait, 820 (56%) people had high hemoglobin A2, 513 (35%) people had high hemoglobin F, and 132 (9%) people had both high hemoglobin F and hemoglobin A2. Our results are very similar to Turkey's beta-thalassemia and SCA trait averages. PMID:17984699

  15. Wnt7a Activates the Planar Cell Polarity Pathway to Drive the Symmetric Expansion of Satellite Stem Cells

    PubMed Central

    Le Grand, Fabien; Jones, Andrew E.; Seale, Vanessa; Scimè, Anthony; Rudnicki, Michael A.

    2009-01-01

    Summary Satellite cells in skeletal muscle are a heterogeneous population of stem cells and committed progenitors. We found that quiescent satellite stem cells expressed the Wnt-receptor Fzd7, and that its candidate ligand Wnt7a was upregulated during regeneration. Notably, Wnt7a markedly stimulated the symmetric expansion of satellite stem cells but did not affect the growth or differentiation of myoblasts. Silencing of Fzd7 abrogated Wnt7a binding and stimulation of stem cell expansion. Wnt7a signaling induced the polarized distribution of the planar cell polarity effector Vangl2. Silencing of Vangl2 inhibited Wnt7a action on satellite stem cell expansion. Wnt7a overexpression enhanced muscle regeneration and increased both the number of satellite cells and the proportion of satellite stem cells. Muscle lacking Wnt7a exhibited a marked decrease in satellite cell number following regeneration. Therefore, Wnt7a signaling through the planar cell polarity pathway controls the homeostatic level of satellite stem cells and hence regulates the regenerative potential of muscle. PMID:19497282

  16. Post-transcriptional regulation of satellite cell quiescence by TTP-mediated mRNA decay

    PubMed Central

    Hausburg, Melissa A; Doles, Jason D; Clement, Sandra L; Cadwallader, Adam B; Hall, Monica N; Blackshear, Perry J; Lykke-Andersen, Jens; Olwin, Bradley B

    2015-01-01

    Skeletal muscle satellite cells in their niche are quiescent and upon muscle injury, exit quiescence, proliferate to repair muscle tissue, and self-renew to replenish the satellite cell population. To understand the mechanisms involved in maintaining satellite cell quiescence, we identified gene transcripts that were differentially expressed during satellite cell activation following muscle injury. Transcripts encoding RNA binding proteins were among the most significantly changed and included the mRNA decay factor Tristetraprolin. Tristetraprolin promotes the decay of MyoD mRNA, which encodes a transcriptional regulator of myogenic commitment, via binding to the MyoD mRNA 3′ untranslated region. Upon satellite cell activation, p38α/β MAPK phosphorylates MAPKAP2 and inactivates Tristetraprolin, stabilizing MyoD mRNA. Satellite cell specific knockdown of Tristetraprolin precociously activates satellite cells in vivo, enabling MyoD accumulation, differentiation and cell fusion into myofibers. Regulation of mRNAs by Tristetraprolin appears to function as one of several critical post-transcriptional regulatory mechanisms controlling satellite cell homeostasis. DOI: http://dx.doi.org/10.7554/eLife.03390.001 PMID:25815583

  17. Post-transcriptional regulation of satellite cell quiescence by TTP-mediated mRNA decay.

    PubMed

    Hausburg, Melissa A; Doles, Jason D; Clement, Sandra L; Cadwallader, Adam B; Hall, Monica N; Blackshear, Perry J; Lykke-Andersen, Jens; Olwin, Bradley B

    2015-01-01

    Skeletal muscle satellite cells in their niche are quiescent and upon muscle injury, exit quiescence, proliferate to repair muscle tissue, and self-renew to replenish the satellite cell population. To understand the mechanisms involved in maintaining satellite cell quiescence, we identified gene transcripts that were differentially expressed during satellite cell activation following muscle injury. Transcripts encoding RNA binding proteins were among the most significantly changed and included the mRNA decay factor Tristetraprolin. Tristetraprolin promotes the decay of MyoD mRNA, which encodes a transcriptional regulator of myogenic commitment, via binding to the MyoD mRNA 3' untranslated region. Upon satellite cell activation, p38α/β MAPK phosphorylates MAPKAP2 and inactivates Tristetraprolin, stabilizing MyoD mRNA. Satellite cell specific knockdown of Tristetraprolin precociously activates satellite cells in vivo, enabling MyoD accumulation, differentiation and cell fusion into myofibers. Regulation of mRNAs by Tristetraprolin appears to function as one of several critical post-transcriptional regulatory mechanisms controlling satellite cell homeostasis. PMID:25815583

  18. FGF2 activates TRPC and Ca2+ signaling leading to satellite cell activation

    PubMed Central

    Liu, Yewei; Schneider, Martin F.

    2013-01-01

    Satellite cells, as stem cells of adult skeletal muscle, are tightly associated with the differentiated muscle fibers and remain quiescent in the absence of muscle damage. In response to an injury, the quiescent satellite cell is activated by soluble factors, including FGFs released from injured myofibers. Using immunostaining, we here first show that TRPC1 channels are highly expressed in satellite cells attached to muscle fibers. Since CD34, a traditional stem cell marker, was recently found to be expressed in skeletal muscle satellite cells we labeled living satellite cells in their physiological niche associated with host FDB fibers using anti-CD34-FITC antibody. We then monitored intra-cellular calcium in anti-CD34-FITC labeled satellite cells attached to muscle fibers using the calcium sensitive dye X rhod-1 which has little fluorescence cross talk with FITC. FGF2 increased intracellular calcium in satellite cells, which was antagonized by the TRPC channel blocker SKF 96365. Immunostaining showed that NFATc3 is highly expressed in satellite cells, but not in host FDB fibers. Elevation of intracellular calcium by FGF2 is accompanied by nuclear translocation of NFATc3 and NFATc2 and by an increase in the number of MyoD positive cells per muscle fiber, both of which were attenuated by TRPC blocker SKF 96365. Our results suggest a novel pathway of satellite cell activation where FGF2 enhances calcium influx through a TRPC channel, and the increased cytosolic calcium leads to both NFATc3 and NFATc2 nuclear translocation and enhanced number of MyoD positive satellite cells per muscle fiber. PMID:24575047

  19. Determination of seasonal changes in wetlands using CHRIS/Proba Hyperspectral satellite images: A case study from Acigöl (Denizli), Turkey.

    PubMed

    Karaman, Muhittin; Budakoglu, Murat; Avci, Damla Uca; Ozelkan, Emre; Bulbul, Ali; Civas, Melda; Tasdelen, Suat

    2015-01-01

    The changes in wetlands that occur through natural processes, as well as through industrialization and agricultural activities, are decreasing and even annihilating the living spaces of endemic species. Acigöl (Denizli, Turkey), which is a suitable habitat for flamingos (Phoenicopterus ruber), is a lake that is affected by seasonal anomalies as a result of being shallow. Acigöl, which is fed by precipitation, groundwater and the springs that occur along tectonic faults, has no water output other than evaporation and industrial activities. In addition to natural factors, it is important to determine the changes in the wetlands of Acig6l, where industrial salt is produced, in order to reveal the micro-ecological equilibrium, the relationship between climate and natural life, and regulation of industrial activities. Remote sensing tools are frequently used in determination of changes in wetlands. Changes in coastlines, water level and area covered by water are parameters that can be examined by remote sensing while investigating wetlands. In this study, the water-covered area was examined using remote sensing. Within the scope of this study, CHRIS/Proba Mode 2 (water bandset) hyperspectral satellite images, acquired on 9/17/2011 for the season and on 6/18/2012 - 6/19/2012 forwet season, were used in orderto present the seasonal changes in Acigöl, during one hydrogeological period. The processes of noise reduction, cloud screening, atmospheric correction, geometric correction, and identification of wetlands have been implemented on the CHRIS/Proba images. In determining the water-covered areas, the Normalized Difference Water Index (NDWI) was used. It was determined that W6 (560 nm) and W18 (1015 nm) and W2 (447 nm) and W18 (1015 nm) band combinations were most appropriate to be used in NDWI to demonstrate the water-land separation. Using Proba-NDWI image, it was established that an area of 27.4 km2 was covered with water during dry season, and 61.2 km2 was covered

  20. Sox2 promotes survival of satellite glial cells in vitro

    SciTech Connect

    Koike, Taro 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.

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

    PubMed Central

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

    2016-01-01

    Summary 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. PMID:27346341

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

    PubMed

    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. PMID:27346341

  3. High concentrations of HGF inhibit skeletal muscle satellite cell proliferation in vitro by inducing expression of myostatin: a possible mechanism for reestablishing satellite cell quiescence in vivo

    PubMed Central

    Yamada, Michiko; Yamanouchi, Keitaro; Hosoyama, Tohru; Shiratsuchi, Sei-ichi; Sato, Akiko; Mizunoya, Wataru; Ikeuchi, Yoshihide; Furuse, Mitsuhiro; Allen, Ronald E.

    2010-01-01

    Skeletal muscle regeneration and work-induced hypertrophy rely on molecular events responsible for activation and quiescence of resident myogenic stem cells, satellite cells. Recent studies demonstrated that hepatocyte growth factor (HGF) triggers activation and entry into the cell cycle in response to mechanical perturbation, and that subsequent expression of myostatin may signal a return to cell quiescence. However, mechanisms responsible for coordinating expression of myostatin after an appropriate time lag following activation and proliferation are not clear. Here we address the possible role of HGF in quiescence through its concentration-dependent negative-feedback mechanism following satellite cell activation and proliferation. When activated/proliferating satellite cell cultures were treated for 24 h beginning 48-h postplating with 10–500 ng/ml HGF, the percentage of bromodeoxyuridine-incorporating cells decreased down to a baseline level comparable to 24-h control cultures in a HGF dose-dependent manner. The high level HGF treatment did not impair the cell viability and differentiation levels, and cells could be reactivated by lowering HGF concentrations to 2.5 ng/ml, a concentration that has been shown to optimally stimulate activation of satellite cells in culture. Coaddition of antimyostatin neutralizing antibody could prevent deactivation and abolish upregulation of cyclin-dependent kinase (Cdk) inhibitor p21. Myostatin mRNA expression was upregulated with high concentrations of HGF, as demonstrated by RT-PCR, and enhanced myostatin protein expression and secretion were revealed by Western blots of the cell lysates and conditioned media. These results indicate that HGF could induce satellite cell quiescence by stimulating myostatin expression. The HGF concentration required (over 10–50 ng/ml), however, is much higher than that for activation, which is initiated by rapid release of HGF from its extracellular association. Considering that HGF is

  4. High concentrations of HGF inhibit skeletal muscle satellite cell proliferation in vitro by inducing expression of myostatin: a possible mechanism for reestablishing satellite cell quiescence in vivo.

    PubMed

    Yamada, Michiko; Tatsumi, Ryuichi; Yamanouchi, Keitaro; Hosoyama, Tohru; Shiratsuchi, Sei-ichi; Sato, Akiko; Mizunoya, Wataru; Ikeuchi, Yoshihide; Furuse, Mitsuhiro; Allen, Ronald E

    2010-03-01

    Skeletal muscle regeneration and work-induced hypertrophy rely on molecular events responsible for activation and quiescence of resident myogenic stem cells, satellite cells. Recent studies demonstrated that hepatocyte growth factor (HGF) triggers activation and entry into the cell cycle in response to mechanical perturbation, and that subsequent expression of myostatin may signal a return to cell quiescence. However, mechanisms responsible for coordinating expression of myostatin after an appropriate time lag following activation and proliferation are not clear. Here we address the possible role of HGF in quiescence through its concentration-dependent negative-feedback mechanism following satellite cell activation and proliferation. When activated/proliferating satellite cell cultures were treated for 24 h beginning 48-h postplating with 10-500 ng/ml HGF, the percentage of bromodeoxyuridine-incorporating cells decreased down to a baseline level comparable to 24-h control cultures in a HGF dose-dependent manner. The high level HGF treatment did not impair the cell viability and differentiation levels, and cells could be reactivated by lowering HGF concentrations to 2.5 ng/ml, a concentration that has been shown to optimally stimulate activation of satellite cells in culture. Coaddition of antimyostatin neutralizing antibody could prevent deactivation and abolish upregulation of cyclin-dependent kinase (Cdk) inhibitor p21. Myostatin mRNA expression was upregulated with high concentrations of HGF, as demonstrated by RT-PCR, and enhanced myostatin protein expression and secretion were revealed by Western blots of the cell lysates and conditioned media. These results indicate that HGF could induce satellite cell quiescence by stimulating myostatin expression. The HGF concentration required (over 10-50 ng/ml), however, is much higher than that for activation, which is initiated by rapid release of HGF from its extracellular association. Considering that HGF is produced

  5. Isolation and Purification of Satellite Cells for Skeletal Muscle Tissue Engineering

    PubMed Central

    Syverud, Brian C; Lee, Jonah D; VanDusen, Keith W; Larkin, Lisa M

    2015-01-01

    Engineered skeletal muscle holds promise as a source of graft tissue for the repair of traumatic injuries such as volumetric muscle loss. The resident skeletal muscle stem cell, the satellite cell, has been identified as an ideal progenitor for tissue engineering due to its role as an essential player in the potent skeletal muscle regeneration mechanism. A significant challenge facing tissue engineers, however, is the isolation of sufficiently large satellite cell populations with high purity. The two common isolation techniques, single fiber explant culture and enzymatic dissociation, can yield either a highly pure satellite cell population or a suitably large number or cells but fail to do both simultaneously. As a result, it is often necessary to use a purification technique such as pre-plating or cell sorting to enrich the satellite cell population post-isolation. Furthermore, the absence of complex chemical and biophysical cues influencing the in vivo satellite cell “niche” complicates the culture of isolated satellite cells. Techniques under investigation to maximize myogenic proliferation and differentiation in vitro are described in this article, along with current methods for isolating and purifying satellite cells. PMID:26413555

  6. Syndecan-3 and syndecan-4 specifically mark skeletal muscle satellite cells and are implicated in satellite cell maintenance and muscle regeneration.

    PubMed

    Cornelison, D D; Filla, M S; Stanley, H M; Rapraeger, A C; Olwin, B B

    2001-11-01

    Myogenesis in the embryo and the adult mammal consists of a highly organized and regulated sequence of cellular processes to form or repair muscle tissue that include cell proliferation, migration, and differentiation. Data from cell culture and in vivo experiments implicate both FGFs and HGF as critical regulators of these processes. Both factors require heparan sulfate glycosaminoglycans for signaling from their respective receptors. Since syndecans, a family of cell-surface transmembrane heparan sulfate proteoglycans (HSPGs) are implicated in FGF signaling and skeletal muscle differentiation, we examined the expression of syndecans 1-4 in embryonic, fetal, postnatal, and adult muscle tissue, as well as on primary adult muscle fiber cultures. We show that syndecan-1, -3, and -4 are expressed in developing skeletal muscle tissue and that syndecan-3 and -4 expression is highly restricted in adult skeletal muscle to cells retaining myogenic capacity. These two HSPGs appear to be expressed exclusively and universally on quiescent adult satellite cells in adult skeletal muscle tissue, suggesting a role for HSPGs in satellite cell maintenance or activation. Once activated, all satellite cells maintain expression of syndecan-3 and syndecan-4 for at least 96 h, also implicating these HSPGs in muscle regeneration. Inhibition of HSPG sulfation by treatment of intact myofibers with chlorate results in delayed proliferation and altered MyoD expression, demonstrating that heparan sulfate is required for proper progression of the early satellite cell myogenic program. These data suggest that, in addition to providing potentially useful new markers for satellite cells, syndecan-3 and syndecan-4 may play important regulatory roles in satellite cell maintenance, activation, proliferation, and differentiation during skeletal muscle regeneration. PMID:11784020

  7. Collagen VI regulates satellite cell self-renewal and muscle regeneration

    PubMed Central

    Urciuolo, Anna; Quarta, Marco; Morbidoni, Valeria; Gattazzo, Francesca; Molon, Sibilla; Grumati, Paolo; Montemurro, Francesca; Tedesco, Francesco Saverio; Blaauw, Bert; Cossu, Giulio; Vozzi, Giovanni; Rando, Thomas A.; Bonaldo, Paolo

    2013-01-01

    Adult muscle stem cells, or satellite cells play essential roles in homeostasis and regeneration of skeletal muscles. Satellite cells are located within a niche that includes myofibers and extracellular matrix. The function of specific extracellular matrix molecules in regulating SCs is poorly understood. Here we show that the extracellular matrix protein collagen VI is a key component of the satellite cell niche. Lack of collagen VI in Col6a1−/− mice causes impaired muscle regeneration and reduced satellite cell self-renewal capability after injury. Collagen VI null muscles display significant decrease of stiffness, which is able to compromise the in vitro and in vivo activity of wild-type satellite cells. When collagen VI is reinstated in vivo by grafting wild-type fibroblasts, the biomechanical properties of Col6a1−/− muscles are ameliorated and satellite cell defects rescued. Our findings establish a critical role for an extracellular matrix molecule in satellite cell self-renewal and open new venues for therapies of collagen VI-related muscle diseases. PMID:23743995

  8. Six family genes control the proliferation and differentiation of muscle satellite cells

    SciTech Connect

    Yajima, Hiroshi; Motohashi, Norio; Ono, Yusuke; Sato, Shigeru; Ikeda, Keiko; Masuda, Satoru; Yada, Erica; Kanesaki, Hironori; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Kawakami, Kiyoshi

    2010-10-15

    Muscle satellite cells are essential for muscle growth and regeneration and their morphology, behavior and gene expression have been extensively studied. However, the mechanisms involved in their proliferation and differentiation remain elusive. Six1 and Six4 proteins were expressed in the nuclei of myofibers of adult mice and the numbers of myoblasts positive for Six1 and Six4 increased during regeneration of skeletal muscles. Six1 and Six4 were expressed in quiescent, activated and differentiated muscle satellite cells isolated from adult skeletal muscle. Overexpression of Six4 and Six5 repressed the proliferation and differentiation of satellite cells. Conversely, knockdown of Six5 resulted in augmented proliferation, and that of Six4 inhibited differentiation. Muscle satellite cells isolated from Six4{sup +/-}Six5{sup -/-} mice proliferated to higher cell density though their differentiation was not altered. Meanwhile, overproduction of Six1 repressed proliferation and promoted differentiation of satellite cells. In addition, Six4 and Six5 repressed, while Six1 activated myogenin expression, suggesting that the differential regulation of myogenin expression is responsible for the differential effects of Six genes. The results indicated the involvement of Six genes in the behavior of satellite cells and identified Six genes as potential target for manipulation of proliferation and differentiation of muscle satellite cells for therapeutic applications.

  9. Asymmetric Distribution of Primary Cilia Allocates Satellite Cells for Self-Renewal.

    PubMed

    Jaafar Marican, Nur Hayati; Cruz-Migoni, Sara B; Borycki, Anne-Gaëlle

    2016-06-14

    Regeneration of vertebrate skeletal muscles requires satellite cells, a population of stem cells that are quiescent in normal conditions and divide, differentiate, and self-renew upon activation triggered by exercise, injury, and degenerative diseases. Satellite cell self-renewal is essential for long-term tissue homeostasis, and previous work has identified a number of external cues that control this process. However, little is known of the possible intrinsic control mechanisms of satellite cell self-renewal. Here, we show that quiescent satellite cells harbor a primary cilium, which is rapidly disassembled upon entry into the cell cycle. Contrasting with a commonly accepted belief, cilia reassembly does not occur uniformly in cells exiting the cell cycle. We found that primary cilia reassemble preferentially in cells committed to self-renew, and disruption of cilia reassembly causes a specific deficit in self-renewing satellite cells. These observations indicate that primary cilia provide an intrinsic cue essential for satellite cell self-renewal. PMID:27161363

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

    PubMed

    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. PMID:27125667

  11. New insights into the epigenetic control of satellite cells

    PubMed Central

    Moresi, Viviana; Marroncelli, Nicoletta; Adamo, Sergio

    2015-01-01

    Epigenetics finely tunes gene expression at a functional level without modifying the DNA sequence, thereby contributing to the complexity of genomic regulation. Satellite cells (SCs) are adult muscle stem cells that are important for skeletal post-natal muscle growth, homeostasis and repair. The understanding of the epigenome of SCs at different stages and of the multiple layers of the post-transcriptional regulation of gene expression is constantly expanding. Dynamic interactions between different epigenetic mechanisms regulate the appropriate timing of muscle-specific gene expression and influence the lineage fate of SCs. In this review, we report and discuss the recent literature about the epigenetic control of SCs during the myogenic process from activation to proliferation and from their commitment to a muscle cell fate to their differentiation and fusion to myotubes. We describe how the coordinated activities of the histone methyltransferase families Polycomb group (PcG), which represses the expression of developmentally regulated genes, and Trithorax group, which antagonizes the repressive activity of the PcG, regulate myogenesis by restricting gene expression in a time-dependent manner during each step of the process. We discuss how histone acetylation and deacetylation occurs in specific loci throughout SC differentiation to enable the time-dependent transcription of specific genes. Moreover, we describe the multiple roles of microRNA, an additional epigenetic mechanism, in regulating gene expression in SCs, by repressing or enhancing gene transcription or translation during each step of myogenesis. The importance of these epigenetic pathways in modulating SC activation and differentiation renders them as promising targets for disease interventions. Understanding the most recent findings regarding the epigenetic mechanisms that regulate SC behavior is useful from the perspective of pharmacological manipulation for improving muscle regeneration and for

  12. Lkb1 is indispensable for skeletal muscle development, regeneration, and satellite cell homeostasis.

    PubMed

    Shan, Tizhong; Zhang, Pengpeng; Liang, Xinrong; Bi, Pengpeng; Yue, Feng; Kuang, Shihuan

    2014-11-01

    Serine/threonine kinase 11, commonly known as liver kinase b1 (Lkb1), is a tumor suppressor that regulates cellular energy metabolism and stem cell function. Satellite cells are skeletal muscle resident stem cells that maintain postnatal muscle growth and repair. Here, we used MyoD(Cre)/Lkb1(flox/flox) mice (called MyoD-Lkb1) to delete Lkb1 in embryonic myogenic progenitors and their descendant satellite cells and myofibers. The MyoD-Lkb1 mice exhibit a severe myopathy characterized by central nucleated myofibers, reduced mobility, growth retardation, and premature death. Although tamoxifen-induced postnatal deletion of Lkb1 in satellite cells using Pax7(CreER) mice bypasses the developmental defects and early death, Lkb1 null satellite cells lose their regenerative capacity cell-autonomously. Strikingly, Lkb1 null satellite cells fail to maintain quiescence in noninjured resting muscles and exhibit accelerated proliferation but reduced differentiation kinetics. At the molecular level, Lkb1 limits satellite cell proliferation through the canonical AMP-activated protein kinase/mammalian target of rapamycin pathway, but facilitates differentiation through phosphorylation of GSK-3β, a key component of the WNT signaling pathway. Together, these results establish a central role of Lkb1 in muscle stem cell homeostasis, muscle development, and regeneration. PMID:25069613

  13. Role of satellite glial cells in gastrointestinal pain

    PubMed Central

    Hanani, Menachem

    2015-01-01

    Gastrointestinal (GI) pain is a common clinical problem, for which effective therapy is quite limited. Sensations from the GI tract, including pain, are mediated largely by neurons in the dorsal root ganglia (DRG), and to a smaller extent by vagal afferents emerging from neurons in the nodose/jugular ganglia. Neurons in rodent DRG become hyperexcitable in models of GI pain (e.g., gastric or colonic inflammation), and can serve as a source for chronic pain. Glial cells are another element in the pain signaling pathways, and there is evidence that spinal glial cells (microglia and astrocytes) undergo activation (gliosis) in various pain models and contribute to pain. Recently it was found that satellite glial cells (SGCs), the main type of glial cells in sensory ganglia, might also contribute to chronic pain in rodent models. Most of that work focused on somatic pain, but in several studies GI pain was also investigated, and these are discussed in the present review. We have shown that colonic inflammation induced by dinitrobenzene sulfonic acid (DNBS) in mice leads to the activation of SGCs in DRG and increases gap junction-mediated coupling among these cells. This coupling appears to contribute to the hyperexcitability of DRG neurons that innervate the colon. Blocking gap junctions (GJ) in vitro reduced neuronal hyperexcitability induced by inflammation, suggesting that glial GJ participate in SGC-neuron interactions. Moreover, blocking GJ by carbenoxolone and other agents reduces pain behavior. Similar changes in SGCs were also found in the mouse nodose ganglia (NG), which provide sensory innervation to most of the GI tract. Following systemic inflammation, SGCs in these ganglia were activated, and displayed augmented coupling and greater sensitivity to the pain mediator ATP. The contribution of these changes to visceral pain remains to be determined. These results indicate that although visceral pain is unique, it shares basic mechanisms with somatic pain

  14. Role of satellite glial cells in gastrointestinal pain.

    PubMed

    Hanani, Menachem

    2015-01-01

    Gastrointestinal (GI) pain is a common clinical problem, for which effective therapy is quite limited. Sensations from the GI tract, including pain, are mediated largely by neurons in the dorsal root ganglia (DRG), and to a smaller extent by vagal afferents emerging from neurons in the nodose/jugular ganglia. Neurons in rodent DRG become hyperexcitable in models of GI pain (e.g., gastric or colonic inflammation), and can serve as a source for chronic pain. Glial cells are another element in the pain signaling pathways, and there is evidence that spinal glial cells (microglia and astrocytes) undergo activation (gliosis) in various pain models and contribute to pain. Recently it was found that satellite glial cells (SGCs), the main type of glial cells in sensory ganglia, might also contribute to chronic pain in rodent models. Most of that work focused on somatic pain, but in several studies GI pain was also investigated, and these are discussed in the present review. We have shown that colonic inflammation induced by dinitrobenzene sulfonic acid (DNBS) in mice leads to the activation of SGCs in DRG and increases gap junction-mediated coupling among these cells. This coupling appears to contribute to the hyperexcitability of DRG neurons that innervate the colon. Blocking gap junctions (GJ) in vitro reduced neuronal hyperexcitability induced by inflammation, suggesting that glial GJ participate in SGC-neuron interactions. Moreover, blocking GJ by carbenoxolone and other agents reduces pain behavior. Similar changes in SGCs were also found in the mouse nodose ganglia (NG), which provide sensory innervation to most of the GI tract. Following systemic inflammation, SGCs in these ganglia were activated, and displayed augmented coupling and greater sensitivity to the pain mediator ATP. The contribution of these changes to visceral pain remains to be determined. These results indicate that although visceral pain is unique, it shares basic mechanisms with somatic pain

  15. Satellited 4q identified in amniotic fluid cells

    SciTech Connect

    Miller, I.; Hsieh, C.L.; Songster, G.

    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.

  16. Isolation and Characterization of Satellite Cells from Rat Head Branchiomeric Muscles

    PubMed Central

    Carvajal Monroy, Paola L.; Yablonka-Reuveni, Zipora; Grefte, Sander; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A.D.T.G.; Von den Hoff, Johannes W.

    2015-01-01

    Fibrosis and defective muscle regeneration can hamper the functional recovery of the soft palate muscles after cleft palate repair. This causes persistent problems in speech, swallowing, and sucking. In vitro culture systems that allow the study of satellite cells (myogenic stem cells) from head muscles are crucial to develop new therapies based on tissue engineering to promote muscle regeneration after surgery. These systems will offer new perspectives for the treatment of cleft palate patients. A protocol for the isolation, culture and differentiation of satellite cells from head muscles is presented. The isolation is based on enzymatic digestion and trituration to release the satellite cells. In addition, this protocol comprises an innovative method using extracellular matrix gel coatings of millimeter size, which requires only low numbers of satellite cells for differentiation assays. PMID:26274878

  17. TRAF6 regulates satellite stem cell self-renewal and function during regenerative myogenesis.

    PubMed

    Hindi, Sajedah M; Kumar, Ashok

    2016-01-01

    Satellite cells are a stem cell population within adult muscle and are responsible for myofiber regeneration upon injury. Satellite cell dysfunction has been shown to underlie the loss of skeletal muscle mass in many acquired and genetic muscle disorders. The transcription factor paired box-protein-7 (PAX7) is indispensable for supplementing the reservoir of satellite cells and driving regeneration in normal and diseased muscle. TNF receptor-associated factor 6 (TRAF6) is an adaptor protein and an E3 ubiquitin ligase that mediates the activation of multiple cell signaling pathways in a context-dependent manner. Here, we demonstrated that TRAF6-mediated signaling is critical for homeostasis of satellite cells and their function during regenerative myogenesis. Selective deletion of Traf6 in satellite cells of adult mice led to profound muscle regeneration defects and dramatically reduced levels of PAX7 and late myogenesis markers. TRAF6 was required for the activation of MAPKs ERK1/2 and JNK1/2, which in turn activated the transcription factor c-JUN, which binds the Pax7 promoter and augments Pax7 expression. Moreover, TRAF6/c-JUN signaling repressed the levels of the microRNAs miR-1 and miR-206, which promote differentiation, to maintain PAX7 levels in satellite cells. We also determined that satellite cell-specific deletion of Traf6 exaggerates the dystrophic phenotype in the mdx (a mouse model of Duchenne muscular dystrophy) mouse by blunting the regeneration of injured myofibers. Collectively, our study reveals an essential role for TRAF6 in satellite stem cell function. PMID:26619121

  18. STAT3 signaling controls satellite cell expansion and skeletal muscle repair

    PubMed Central

    Tierney, Matthew Timothy; Aydogdu, Tufan; Sala, David; Malecova, Barbora; Gatto, Sole; Puri, Pier Lorenzo; Latella, Lucia; Sacco, Alessandra

    2015-01-01

    The progression of disease- and age-dependent skeletal muscle wasting results in part from a decline in the number and function of satellite cells, the direct cellular contributors to muscle repair1–10. However, little is known about the molecular effectors underlying satellite cell impairment and depletion. Elevated levels of inflammatory cytokines, including interleukin-6 (IL-6), are associated with both age-related and muscle-wasting conditions11–13. The levels of STAT3, a downstream effector of IL-6, are also elevated with muscle wasting14,15, and STAT3 has been implicated in the regulation of self-renewal and stem cell fate in several tissues16–19. Here we show that IL-6–activated Stat3 signaling regulates satellite cell behavior, promoting myogenic lineage progression through myogenic differentiation 1 (Myod1) regulation. Conditional ablation of Stat3 in Pax7-expressing satellite cells resulted in their increased expansion during regeneration, but compromised myogenic differentiation prevented the contribution of these cells to regenerating myofibers. In contrast, transient Stat3 inhibition promoted satellite cell expansion and enhanced tissue repair in both aged and dystrophic muscle. The effects of STAT3 inhibition were conserved in human myoblasts. The results of this study indicate that pharmacological manipulation of STAT3 activity can be used to counteract the functional exhaustion of satellite cells, thereby maintaining the endogenous regenerative response and ameliorating muscle-wasting diseases. PMID:25194572

  19. Istanbul, Turkey

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This June 16, 2000 image of Istanbul, Turkey show a full 60 by 60 km ASTER scene in the visible and infrared channels. Vegetation appears red, and urban areas blue-green. Bustling Istanbul, with its magnificent historical heritage, has spanned the divide between Europe and Asia for more than 2,500 years. Originally called Byzantium, the city was founded in the 7th century BC on the Golden Horn, an arm of the narrow Bosporus (also spelled Bosphorus) Strait, which connects the Sea of Marmara to the south, with the Black Sea to the north. Constantine I made it his capital of the Eastern Roman Empire in AD 330. As Constantinople, the strategically located city arose as the preeminent cultural, religious, and political center of the Western world. It reached the height of its wealth and glory in the early 5th century. After centuries of decline, the city entered another period of tremendous growth and prosperity when, as Istanbul, it became the capital of the Turkish Ottoman Empire in 1457. Although Turkey moved its capital to Ankara in 1923, Istanbul remains the nation's largest city with a population of over 8 million, its commercial center, and a major port. Two bridges spanning the Bosporus, and ships in the busy channel can be seen on the enlargement. On the image, the water areas have been replaced with a thermal image: colder waters are displayed in dark blue, warmer areas in light blue. Note the dark lines showing boat wakes, and the cold water entering the Sea of Marmara from deeper waters of the Bosporus.

    Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. Dr. Anne Kahle at NASA's Jet Propulsion Laboratory, Pasadena, Calif., is the U

  20. A home away from home: challenges and opportunities in engineering in vitro muscle satellite cell niches

    PubMed Central

    Cosgrove, Benjamin D.; Sacco, Alessandra; Gilbert, Penney M.; Blau, Helen M.

    2009-01-01

    Satellite cells are skeletal muscle stem cells with a principal role in postnatal skeletal muscle regeneration. Satellite cells, like many tissue-specific adult stem cells, reside in a quiescent state in an instructive, anatomically defined niche. The satellite cell niche constitutes a distinct membrane-enclosed compartment within the muscle fiber, containing a diversity of biochemical and biophysical signals that influence satellite cell function. A major limitation to the study and clinical utility of satellite cells is that upon removal from the muscle fiber and plating in traditional plastic tissue culture platforms, their muscle stem cell properties are rapidly lost. Clearly, the maintenance of stem cell function is critically dependent on in vivo niche signals, highlighting the need to create novel in vitro microenvironments that allow for the maintenance and propagation of satellite cells while retaining their potential to function as muscle stem cells. Here, we discuss how emerging biomaterials technologies offer great promise for engineering in vitro microenvironments to meet these challenges. In engineered biomaterials, signaling molecules can be presented in a manner that more closely mimics cell-cell and cell-matrix interactions and matrices can be fabricated with diverse rigidities that approximate in vivo tissues. The development of in vitro microenvironments in which niche features can be systematically modulated will be instrumental not only to future insights into muscle stem cell biology and therapeutic approaches to muscle diseases and muscle wasting with aging, but also will provide a paradigm for the analysis of numerous adult tissue-specific stem cells. PMID:19751902

  1. Recombinant insulin-like growth factor-1 activates satellite cells in the mouse urethral rhabdosphincter

    PubMed Central

    2013-01-01

    Background The goal of this study is to demonstrate the efficacy of a new method for the treatment of urinary incontinence by stimulation of urethral rhabdosphincter satellite cells. We show that satellite cells do exist in the sphincter muscle of retired male mice breeders by staining for c-Met, a satellite cell specific protein. Once activated by recombinant mouse Insulin-like Growth Factor-1(rIgf-1), the satellite cells develop into muscle cells within the rhabdosphincter thereby potentially strengthening it. Methods 20 μl (1 μg/μl) of rIgf-1 was surgically injected directly into the urethral wall of retired male mouse breeders. Mice injected with phosphate buffered saline (PBS) were used as controls. 4 weeks later, urethras were harvested and serially-sectioned through the sphincter for routine hematoxylin-eosin staining as well as immunohistochemical staining with satellite cell specific anti-c-Met antibody and proliferation specific anti-Ki-67 antibody. Results Anti-c-Met antibody positive cells (c-Met+) were identified in the rhabdosphincter. c-Met+ cells increased by 161.8% relative to controls four weeks after rIGF-1 injection. Anti- Ki-67 antibody positive cells were identified and characterized as cells with centrally located nuclei in striated muscle bundles of rIGF-1 treated animals. Conclusions Satellite cells in the mouse rhabdosphincter can be activated by rIGF-1 treatment, which subsequently are incorporated into existing skeletal muscle bundles. Using this approach, the rhabdosphincter can be induced to regenerate and potentially strengthen via satellite cell activation and likely improve urinary continence. PMID:24279352

  2. Acute effects of hindlimb unweighting on satellite cells of growing skeletal muscle

    NASA Technical Reports Server (NTRS)

    Schultz, Edward; Darr, Kevin C.; Macius, Allison

    1994-01-01

    The proliferative behavior of satellite cells in growing rat soleus and extensor digitorum longus muscles was examined at short periods after initiation of hindlimb unweighting. Mitotic activity of satellite cells in both muscles decreased below weight-bearing control levels within 24 h of initiation of hindlimb unweighting. This satellite cell response was equal to or greater than 48 h before any atrophic morphological changes that take place in the muscles. Suppression of mitotic activity was most severe in the soleus muscle where continuous infusion of label demonstrated that virtually all mitotic activity was abolished between 3 and 5 days. The results of this study suggest that satellite cell mitotic activity is a sensitive indicator of primary atrophic changes occurring in growing myofibers and may be a predictor of future morphological changes.

  3. Myostatin suppression of Akirin1 mediates glucocorticoid-induced satellite cell dysfunction.

    PubMed

    Dong, Yanjun; Pan, Jenny S; Zhang, Liping

    2013-01-01

    Glucocorticoids production is increased in many pathological conditions that are associated with muscle loss, but their role in causing muscle wasting is not fully understood. We have demonstrated a new mechanism of glucocorticoid-induced muscle atrophy: Dexamethasone (Dex) suppresses satellite cell function contributing to the development of muscle atrophy. Specifically, we found that Dex decreases satellite cell proliferation and differentiation in vitro and in vivo. The mechanism involved Dex-induced upregulation of myostatin and suppression of Akirin1, a promyogenic gene. When myostatin was inhibited in Dex-treated mice, Akirin1 expression increased as did satellite cell activity, muscle regeneration and muscle growth. In addition, silencing myostatin in myoblasts or satellite cells prevented Dex from suppressing Akirin1 expression and cellular proliferation and differentiation. Finally, overexpression of Akirin1 in myoblasts increased their expression of MyoD and myogenin and improved cellular proliferation and differentiation, theses improvements were no longer suppressed by Dex. We conclude that glucocorticoids stimulate myostatin which inhibits Akirin1 expression and the reparative functions of satellite cells. These responses attribute to muscle atrophy. Thus, inhibition of myostatin or increasing Akirin1 expression could lead to therapeutic strategies for improving satellite cell activation and enhancing muscle growth in diseases associated with increased glucocorticoid production. PMID:23516508

  4. Myostatin Suppression of Akirin1 Mediates Glucocorticoid-Induced Satellite Cell Dysfunction

    PubMed Central

    Dong, Yanjun; Pan, Jenny S.; Zhang, Liping

    2013-01-01

    Glucocorticoids production is increased in many pathological conditions that are associated with muscle loss, but their role in causing muscle wasting is not fully understood. We have demonstrated a new mechanism of glucocorticoid-induced muscle atrophy: Dexamethasone (Dex) suppresses satellite cell function contributing to the development of muscle atrophy. Specifically, we found that Dex decreases satellite cell proliferation and differentiation in vitro and in vivo. The mechanism involved Dex-induced upregulation of myostatin and suppression of Akirin1, a promyogenic gene. When myostatin was inhibited in Dex-treated mice, Akirin1 expression increased as did satellite cell activity, muscle regeneration and muscle growth. In addition, silencing myostatin in myoblasts or satellite cells prevented Dex from suppressing Akirin1 expression and cellular proliferation and differentiation. Finally, overexpression of Akirin1 in myoblasts increased their expression of MyoD and myogenin and improved cellular proliferation and differentiation, theses improvements were no longer suppressed by Dex. We conclude that glucocorticoids stimulate myostatin which inhibits Akirin1 expression and the reparative functions of satellite cells. These responses attribute to muscle atrophy. Thus, inhibition of myostatin or increasing Akirin1 expression could lead to therapeutic strategies for improving satellite cell activation and enhancing muscle growth in diseases associated with increased glucocorticoid production. PMID:23516508

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

    PubMed Central

    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:DsRedloxP/loxPCripto-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. PMID:26052513

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

    SciTech Connect

    Zhang, Pengpeng; Liang, Xinrong; Shan, Tizhong; Jiang, Qinyang; Deng, Changyan; Zheng, Rong; Kuang, Shihuan

    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.

  7. Isolation and Culture of Skeletal Muscle Myofibers as a Means to Analyze Satellite Cells

    PubMed Central

    Shefer, Gabi; Yablonka-Reuveni, Zipora

    2012-01-01

    Summary Myofibers are the functional contractile units of skeletal muscle. Mononuclear satellite cells located between the basal lamina and the plasmalemma of the myofiber are the primary source of myogenic precursor cells in postnatal muscle. This chapter describes protocols used in our laboratory for isolation, culturing and immunostaining of single myofibers from mouse skeletal muscle. The isolated myofibers are intact and retain their associated satellite cells underneath the basal lamina. The first protocol discusses myofiber isolation from the flexor digitorum brevis (FDB) muscle. Myofibers are cultured in dishes coated with Vitrogen collagen and satellite cells remain associated with the myofibers undergoing proliferation and differentiation on the myofiber surface. The second protocol discusses the isolation of longer myofibers from the extensor digitorum longus (EDL). Different from the FDB myofibers, the longer EDL myofibers tend to tangle and break if cultured together; therefore, EDL myofibers are cultured individually. These myofibers are cultured in dishes coated with Matrigel. The satellite cells initially remain associated with the myofiber and later migrate away to its vicinity, resulting in extensive cell proliferation and differentiation. These culture protocols allow studies on the interplay between the myofiber and its associated satellite cells. PMID:15361669

  8. CD34 promotes satellite cell motility and entry into proliferation to facilitate efficient skeletal muscle regeneration.

    PubMed

    Alfaro, Leslie Ann So; Dick, Sarah A; Siegel, Ashley L; Anonuevo, Adam S; McNagny, Kelly M; Megeney, Lynn A; Cornelison, D D W; Rossi, Fabio M V

    2011-12-01

    Expression of the cell surface sialomucin CD34 is common to many adult stem cell types, including muscle satellite cells. However, no clear stem cell or regeneration-related phenotype has ever been reported in mice lacking CD34, and its function on these cells remains poorly understood. Here, we assess the functional role of CD34 on satellite cell-mediated muscle regeneration. We show that Cd34(-/-) mice, which have no obvious developmental phenotype, display a defect in muscle regeneration when challenged with either acute or chronic muscle injury. This regenerative defect is caused by impaired entry into proliferation and delayed myogenic progression. Consistent with the reported antiadhesive function of CD34, knockout satellite cells also show decreased motility along their host myofiber. Altogether, our results identify a role for CD34 in the poorly understood early steps of satellite cell activation and provide the first evidence that beyond being a stem cell marker, CD34 may play an important function in modulating stem cell activity. PMID:21997891

  9. CD34 Promotes Satellite Cell Motility and Entry into Proliferation to Facilitate Efficient Skeletal Muscle Regeneration

    PubMed Central

    Alfaro, Leslie Ann So; Dick, Sarah A.; Siegel, Ashley L.; Anonuevo, Adam S.; McNagny, Kelly M.; Megeney, Lynn A.; Cornelison, Dawn D.W.; Rossi, Fabio M.V.

    2013-01-01

    Expression of the cell surface sialomucin CD34 is common to many adult stem cell types, including muscle satellite cells. However, no clear stem cell or regeneration-related phenotype has ever been reported in mice lacking CD34, and its function on these cells remains poorly understood. Here, we assess the functional role of CD34 on satellite cell-mediated muscle regeneration. We show that Cd34−/− mice, which have no obvious developmental phenotype, display a defect in muscle regeneration when challenged with either acute or chronic muscle injury. This regenerative defect is caused by impaired entry into proliferation and delayed myogenic progression. Consistent with the reported anti-adhesive function of CD34, knock out satellite cells also show decreased motility along their host myofiber. Altogether, our results identify a role for CD34 in the poorly understood early steps of satellite cell activation, and provide the first evidence that beyond being a stem cell marker, CD34 may play an important function in modulating stem cell activity. PMID:21997891

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

    SciTech Connect

    Nagata, Yosuke 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

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

    PubMed

    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 (P<0.05). Fusion index was reduced in RES lambs at 3 months of age compared with CON (P<0.001). Restricted nutrition during gestation alters the temporal expression of myogenic regulatory factors in satellite cells of the

  12. Eph/ephrin interactions modulate muscle satellite cell motility and patterning.

    PubMed

    Stark, Danny A; Karvas, Rowan M; Siegel, Ashley L; Cornelison, D D W

    2011-12-01

    During development and regeneration, directed migration of cells, including neural crest cells, endothelial cells, axonal growth cones and many types of adult stem cells, to specific areas distant from their origin is necessary for their function. We have recently shown that adult skeletal muscle stem cells (satellite cells), once activated by isolation or injury, are a highly motile population with the potential to respond to multiple guidance cues, based on their expression of classical guidance receptors. We show here that, in vivo, differentiated and regenerating myofibers dynamically express a subset of ephrin guidance ligands, as well as Eph receptors. This expression has previously only been examined in the context of muscle-nerve interactions; however, we propose that it might also play a role in satellite cell-mediated muscle repair. Therefore, we investigated whether Eph-ephrin signaling would produce changes in satellite cell directional motility. Using a classical ephrin 'stripe' assay, we found that satellite cells respond to a subset of ephrins with repulsive behavior in vitro; patterning of differentiating myotubes is also parallel to ephrin stripes. This behavior can be replicated in a heterologous in vivo system, the hindbrain of the developing quail, in which neural crest cells are directed in streams to the branchial arches and to the forelimb of the developing quail, where presumptive limb myoblasts emigrate from the somite. We hypothesize that guidance signaling might impact multiple steps in muscle regeneration, including escape from the niche, directed migration to sites of injury, cell-cell interactions among satellite cell progeny, and differentiation and patterning of regenerated muscle. PMID:22071104

  13. Eph/ephrin interactions modulate muscle satellite cell motility and patterning

    PubMed Central

    Stark, Danny A.; Karvas, Rowan M.; Siegel, Ashley L.; Cornelison, D. D. W.

    2011-01-01

    During development and regeneration, directed migration of cells, including neural crest cells, endothelial cells, axonal growth cones and many types of adult stem cells, to specific areas distant from their origin is necessary for their function. We have recently shown that adult skeletal muscle stem cells (satellite cells), once activated by isolation or injury, are a highly motile population with the potential to respond to multiple guidance cues, based on their expression of classical guidance receptors. We show here that, in vivo, differentiated and regenerating myofibers dynamically express a subset of ephrin guidance ligands, as well as Eph receptors. This expression has previously only been examined in the context of muscle-nerve interactions; however, we propose that it might also play a role in satellite cell-mediated muscle repair. Therefore, we investigated whether Eph-ephrin signaling would produce changes in satellite cell directional motility. Using a classical ephrin ‘stripe’ assay, we found that satellite cells respond to a subset of ephrins with repulsive behavior in vitro; patterning of differentiating myotubes is also parallel to ephrin stripes. This behavior can be replicated in a heterologous in vivo system, the hindbrain of the developing quail, in which neural crest cells are directed in streams to the branchial arches and to the forelimb of the developing quail, where presumptive limb myoblasts emigrate from the somite. We hypothesize that guidance signaling might impact multiple steps in muscle regeneration, including escape from the niche, directed migration to sites of injury, cell-cell interactions among satellite cell progeny, and differentiation and patterning of regenerated muscle. PMID:22071104

  14. Inducible depletion of satellite cells in adult, sedentary mice impairs muscle regenerative capacity without affecting sarcopenia.

    PubMed

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

    2015-01-01

    A key determinant of geriatric frailty is sarcopenia, the age-associated loss of skeletal muscle mass and strength. Although the etiology of sarcopenia is unknown, the correlation during aging between the loss of activity of satellite cells, which are endogenous muscle stem cells, and impaired muscle regenerative capacity has led to the hypothesis that the loss of satellite cell activity is also a cause of sarcopenia. We tested this hypothesis in male sedentary mice by experimentally depleting satellite cells in young adult animals to a degree sufficient to impair regeneration throughout the rest of their lives. A detailed analysis of multiple muscles harvested at various time points during aging in different cohorts of these mice showed that the muscles were of normal size, despite low regenerative capacity, but did have increased fibrosis. These results suggest that lifelong reduction of satellite cells neither accelerated nor exacerbated sarcopenia and that satellite cells did not contribute to the maintenance of muscle size or fiber type composition during aging, but that their loss may contribute to age-related muscle fibrosis. PMID:25501907

  15. Muscle satellite cell proliferation and association: new insights from myofiber time-lapse imaging

    PubMed Central

    2011-01-01

    Background As the resident stem cells of skeletal muscle, satellite cells are activated by extracellular cues associated with local damage. Once activated, satellite cells will re-enter the cell cycle to proliferate and supply a population of myoblasts, which will repair or replace damaged myofibers by differentiating and fusing either with an existing myofiber or with each other. There is also evidence that the orientation of cell division with respect to the myofiber may indicate or convey asymmetry in the two daughter cells. Our recent studies with time-lapse imaging of myofiber-associated satellite cells in vitro have yielded new data on the timing and orientation of satellite cell divisions, and revealed persistent differences in the behavior of daughter cells from planar versus vertical divisions. Results We analyzed 244 individual fiber-associated satellite cells in time-lapse video from 24 to 48 hours after myofiber harvest. We found that initial cell division in fiber culture is not synchronous, although presumably all cells were activated by the initial trauma of harvest; that cell cycling time is significantly shorter than previously thought (as short as 4.8 hours, averaging 10 hours between the first and second divisions and eight hours between the second and third); and that timing of subsequent divisions is not strongly correlated with timing of the initial division. Approximately 65% of first and 80% of second cell divisions occur parallel to the axis of the myofiber, whereas the remainder occur outside the plane of the fiber surface (vertical division). We previously demonstrated that daughter cells frequently remain associated with each other after division or reassociate after a brief separation, and that unrelated cells may also associate for significant periods of time. We show in this paper that daughter cells resulting from a vertical division remain associated with one another several times longer than do daughters from a horizontal division

  16. Characteristics of the Localization of Connexin 43 in Satellite Cells during Skeletal Muscle Regeneration In Vivo.

    PubMed

    Ishido, Minenori; Kasuga, Norikatsu

    2015-04-28

    For myogenesis, new myotubes are formed by the fusion of differentiated myoblasts. In the sequence of events for myotube formation, intercellular communication through gap junctions composed of connexin 43 (Cx43) plays critical roles in regulating the alignment and fusion of myoblasts in advances of myotube formation in vitro. On the other hand, the relationship between the expression patterns of Cx43 and the process of myotube formation in satellite cells during muscle regeneration in vivo remains poorly understood. The present study investigated the relationship between Cx43 and satellite cells in muscle regeneration in vivo. The expression of Cx43 was detected in skeletal muscles on day 1 post-muscle injury, but not in control muscles. Interestingly, the expression of Cx43 was not localized on the inside of the basement membrane of myofibers in the regenerating muscles. Moreover, although the clusters of differentiated satellite cells, which represent a more advanced stage of myotube formation, were observed on the inside of the basement membrane of myofibers in regenerating muscles, the expression of Cx43 was not localized in the clusters of these satellite cells. Therefore, in the present study, it was suggested that Cx43 may not directly contribute to muscle regeneration via satellite cells. PMID:26019374

  17. Analytic studies on satellite detection of severe, two-cell tornadoes

    NASA Technical Reports Server (NTRS)

    Carrier, G. F.; Dergarabedian, P.; Fendell, F. E.

    1979-01-01

    It is argued that a two-cell structure is likely to be the unique property, and potentially satellite-accessible observable, of the exceptionally severe tornado. Analysis elucidating the dynamic, thermodynamic, and geometric properties of this two-cell structure is described. The analysis ultimately will furnish instrumentation requirements.

  18. Context matters: in vivo and in vitro influences on muscle satellite cell activity.

    PubMed

    Cornelison, D D W

    2008-10-15

    Skeletal muscle is formed during development by the progressive specification, proliferation, migration, and fusion of myoblasts to form terminally differentiated, contractile, highly patterned myofibers. Skeletal muscle is repaired or replaced postnatally by a similar process, involving a resident myogenic stem cell population referred to as satellite cells. In both cases, the activity of the myogenic precursor cells in question is regulated by local signals from the environment, frequently involving other, non-muscle cell types. However, while the majority of studies on muscle development were done in the context of the whole embryo, much of the current work on muscle satellite cells has been done in vitro, or on satellite cell-derived cell lines. While significant practical reasons for these approaches exist, it is almost certain that important influences from the context of the injured and regenerating muscle are lost, while potential tissue culture artifacts are introduced. This review will briefly address extracellular influences on satellite cells in vivo and in vitro that would be expected to impinge on their activity. PMID:18759329

  19. Cell culture as a tool for the study of poultry skeletal muscle development.

    PubMed

    McFarland, D C

    1992-03-01

    Postnatal development of skeletal muscle is the responsibility of the myogenic satellite cells. Satellite cells, isolated from the pectoralis major muscle of young growing tom turkeys, have been cultured in vitro to provide a system for studying cellular and hormonal aspects of poultry skeletal muscle development. Satellite cell clones derived from primary cultures have been developed so that in vitro observations would not be confounded by the presence of nonmyogenic cells. Likewise, a serum-free medium that promotes proliferation of the turkey satellite cell has been developed to provide a hormonally controlled environment for in vitro developmental studies. These two techniques have enabled us to examine the following: 1) factors that influence satellite cell proliferation and differentiation, 2) the interaction of hormones with cellular receptors, 3) secretion of biologically important proteins from cells and 4) the expression of genes important to muscle development. PMID:1371806

  20. VAMP2 is expressed in muscle satellite cells and up-regulated during muscle regeneration.

    PubMed

    Tajika, Yuki; Sato, Mahito; Murakami, Tohru; Takata, Kuniaki; Yorifuji, Hiroshi

    2007-06-01

    Membrane trafficking is one of the most important mechanisms involved in the establishment and maintenance of the forms and functions of the cell. However, it is poorly understood in skeletal muscle cells. In this study, we have focused on vesicle-associated membrane proteins (VAMPs), which are components of the vesicle docking and fusion complex, and have performed immunostaining to investigate the expression of VAMPs in rat skeletal muscle tissue. We have found that VAMP2, but not VAMP1 or VAMP3, is expressed in satellite cells. VAMP2 is also expressed in myofibers in the soleus muscle and nerve endings. This is consistent with previous studies in which VAMP2 has been shown to regulate GLUT4 trafficking in slow-twitch myofibers in soleus muscle and neurotransmitter release in nerve endings. As satellite cells are quiescent myogenic cells, the expression of VAMP2 has further been examined in regenerating muscles after injury by the snake venom, cardiotoxin; we have observed enhanced expression of VAMP2 in immature myotubes with a peak at 3 days after injury. Our findings suggest that VAMP2 plays roles in quiescent satellite cells and is involved in muscle regeneration. The nature of the material transported in the VAMP2-bearing vesicles in satellite cells and myotubes is still under investigation. PMID:17468895

  1. [Comparative studies on detection of Chlamydophila psittaci and Chlamydophila abortus in meat turkey flocks using cell culture, ELISA, and PCR].

    PubMed

    Sting, R; Lerke, E; Hotzel, H; Jodas, S; Popp, C; Hafez, H M

    2006-02-01

    The prevalence of chlamydia in 10 meat turkey flocks was investigated. As samples served of each moment of collection and sex of the animals 10 cloacal swabs which were taken at the age of 1, 4, 8 and 12 (females) or 16 weeks (males) and at the time of slaughter at the age of 16 or 20 weeks. Spleen samples were taken at the time of slaughter, additionally. These were pooled making 1 pool out of 5 individual samples. The cloacal and spleen pools were examined by nested PCR (nPCR), Capture-ELISA and Capture Blocking-ELISA directly as well as after isolation attempts in cell cultures. The most sensitive method to detect chlamydia, with 6 isolates proved to be the isolation by cell culture followed by detection using nPCR. Not corresponding to the results of the nPCR were 4 positive reactions found by the Capture-ELISA which could in no case be affirmed by Capture-Blocking-ELISA. The direct examination of cloacal swab pools by nPCR proved positive in only 2 cases. In contrast to this the examination of these samples by Capture-ELISA showed a high percentage of 71.9% positive results, of which only 2 cases were confirmed by nPCR and none by Capture-Blocking-ELISA. Of the 8 Chlamydia positive results in the nPCR 7 could be classified by DNA sequencing to Cp. abortus and only one to Cp. psittaci. PMID:16555483

  2. Evaluation of solar cells for potential space satellite power applications

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The evaluation focused on the following subjects: (1) the relative merits of alternative solar cell materials, based on performance and availability, (2) the best manufacturing methods for various solar cell options and the effects of extremely large production volumes on their ultimate costs and operational characteristics, (3) the areas of uncertainty in achieving large solar cell production volumes, (4) the effects of concentration ratios on solar array mass and system performance, (5) the factors influencing solar cell life in the radiation environment during transport to and in geosynchronous orbit, and (6) the merits of conducting solar cell manufacturing operations in space.

  3. Isolation and Culture of Skeletal Muscle Myofibers as a Means to Analyze Satellite Cells

    PubMed Central

    Keire, Paul; Shearer, Andrew; Shefer, Gabi; Yablonka-Reuveni, Zipora

    2012-01-01

    Multinucleated myofibers are the functional contractile units of skeletal muscle. In adult muscle, mononuclear satellite cells, located between the basal lamina and the plasmalemma of the myofiber, are the primary myogenic stem cells. This chapter describes protocols for isolation, culturing and immunostaining of myofibers from mouse skeletal muscle. Myofibers are isolated intact and retain their associated satellite cells. The first protocol discusses myofiber isolation from the flexor digitorum brevis (FDB) muscle. These short myofibers are cultured in dishes coated with PureCol collagen (formerly known as Vitrogen) using a serum replacement medium. Employing such culture conditions, satellite cells remain associated with the myofibers, undergoing proliferation and differentiation on the myofiber surface. The second protocol discusses the isolation of longer myofibers from the extensor digitorum longus (EDL) muscle. Different from the FDB preparation, where multiple myofibers are processed together, the longer EDL myofibers are typically processed and cultured individually in dishes coated with Matrigel using a growth factor rich medium. Under these conditions, satellite cells initially remain associated with the parent myofiber and later migrate away, giving rise to proliferating and differentiating progeny. Myofibers from other types of muscles, such as diaphragm, masseter, and extraocular muscles can also be isolated and analyzed using protocols described herein. Overall, cultures of isolated myofibers provide essential tools for studying the interplay between the parent myofiber and its associated satellite cells. The current chapter provides background, procedural, and reagent updates, and step-by-step images of FDB and EDL muscle isolations, not included in our 2005 publication in this series. PMID:23179849

  4. Turkey`s nuclear power effort

    SciTech Connect

    Aybers, N.

    1995-12-01

    This paper discusses the expected role of nuclear energy in the production of electric power to serve the growing needs of Turkey, examining past activities and recent developments. The paper also reviews Turkey`s plans with respect to nuclear energy and the challenges that the country faces along the way.

  5. Inadequate satellite cell replication compromises muscle regrowth following postnatal nutrient restriction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Perinatal growth impairment permanently compromises skeletal muscle mass. The present study assessed the contribution of muscle satellite cell replicative capacity to this deficit. Mouse dams were fed either a low protein (LP, n=7) or control (C, n=6) diet during lactation. Pups were weaned at 21 d ...

  6. Characterization of a plasma membrane glycoprotein common to myoblasts, skeletal muscle satellite cells, and glia.

    PubMed

    Wakshull, E; Bayne, E K; Chiquet, M; Fambrough, D M

    1983-12-01

    A plasma membrane glycoprotein common to embryonic chick myoblasts and adult chicken skeletal muscle satellite cells is the antigen recognized by monoclonal antibody C3/1. Although traces of the same antigen are present on some muscle-derived fibroblasts, the density of antigenic sites on myoblasts and satellite cells is so high that these cell types can be identified in tissues by immunocytochemical techniques. The antigen is exposed on the surfaces of myogenic cells growing in tissue culture and can be solubilized with detergent. This and other criteria establish that the antigen is a plasma membrane protein. The antigen, purified by affinity techniques, consists of a single type of polypeptide chain which migrates as a relatively broad band of apparent molecular weight 38,000 Da in SDS-polyacrylamide gel electrophoresis. It has a very small sedimentation constant, suggesting that the solubilized form is either monomeric or dimeric. The concentration of antigenic sites increases during myogenesis in vitro; but during maturation the antigenic sites are lost from muscle fibers. Electron microscopic autoradiographic study of adult muscle labeled with iodinated monoclonal antibody demonstrated unequivocally that the antigenic sites in adult muscle are concentrated in the satellite cells. Although selective for myoblasts, immature myotubes and satellite cells in the myogenic lineage, the monoclonal antibody also binds at rather high levels to peripheral Schwann cells and teloglia, to some nonneuronal cells in cultures derived from embryonic spinal cord, to some glial elements of adult chicken brain, and to several cell types in the early embryo. PMID:6360753

  7. The Hippo pathway member Yap plays a key role in influencing fate decisions in muscle satellite cells

    PubMed Central

    Judson, Robert N.; Tremblay, Annie M.; Knopp, Paul; White, Robert B.; Urcia, Roby; De Bari, Cosimo; Zammit, Peter S.; Camargo, Fernando D.; Wackerhage, Henning

    2012-01-01

    Summary Satellite cells are the resident stem cells of skeletal muscle. Mitotically quiescent in mature muscle, they can be activated to proliferate and generate myoblasts to supply further myonuclei to hypertrophying or regenerating muscle fibres, or self-renew to maintain the resident stem cell pool. Here, we identify the transcriptional co-factor Yap as a novel regulator of satellite cell fate decisions. Yap expression increases during satellite cell activation and Yap remains highly expressed until after the differentiation versus self-renewal decision is made. Constitutive expression of Yap maintains Pax7+ and MyoD+ satellite cells and satellite cell-derived myoblasts, promotes proliferation but prevents differentiation. In contrast, Yap knockdown reduces the proliferation of satellite cell-derived myoblasts by ≈40%. Consistent with the cellular phenotype, microarrays show that Yap increases expression of genes associated with Yap inhibition, the cell cycle, ribosome biogenesis and that it represses several genes associated with angiotensin signalling. We also identify known regulators of satellite cell function such as BMP4, CD34 and Myf6 (Mrf4) as genes whose expression is dependent on Yap activity. Finally, we confirm in myoblasts that Yap binds to Tead transcription factors and co-activates MCAT elements which are enriched in the proximal promoters of Yap-responsive genes. PMID:23038772

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

    NASA Technical Reports Server (NTRS)

    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.

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

    SciTech Connect

    Chatterjee, Somik; Yin, Hongshan; Nam, Deokhwa; Li, Yong; Ma, Ke

    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.

  10. Three-Dimensional Culture Assay to Explore Cancer Cell Invasiveness and Satellite Tumor Formation.

    PubMed

    Côté, Marie-France; Turcotte, Audrey; Doillon, Charles; Gobeil, Stephane

    2016-01-01

    Mammalian cell culture in monolayers is widely used to study various physiological and molecular processes. However, this approach to study growing cells often generates unwanted artifacts. Therefore, cell culture in a three-dimensional (3D) environment, often using extracellular matrix components, emerged as an interesting alternative due to its close similarity to the native in vivo tissue or organ. We developed a 3D cell culture system using two compartments, namely (i) a central compartment containing cancer cells embedded in a collagen gel acting as a pseudo-primary macrospherical tumor and (ii) a peripheral cell-free compartment made of a fibrin gel, i.e. an extracellular matrix component different from that used in the center, in which cancer cells can migrate (invasion front) and/or form microspherical tumors representing secondary or satellite tumors. The formation of satellite tumors in the peripheral compartment is remarkably correlated to the known aggressiveness or metastatic origin of the native tumor cells, which makes this 3D culture system unique. This cell culture approach might be considered to assess cancer cell invasiveness and motility, cell-extracellular matrix interactions and as a method to evaluate anti-cancer drug properties. PMID:27585303

  11. The p38alpha/beta MAPK functions as a molecular switch to activate the quiescent satellite cell.

    PubMed

    Jones, Nathan C; Tyner, Kristina J; Nibarger, Lisa; Stanley, Heather M; Cornelison, Dawn D W; Fedorov, Yuri V; Olwin, Bradley B

    2005-04-11

    Somatic stem cells cycle slowly or remain quiescent until required for tissue repair and maintenance. Upon muscle injury, stem cells that lie between the muscle fiber and basal lamina (satellite cells) are activated, proliferate, and eventually differentiate to repair the damaged muscle. Satellite cells in healthy muscle are quiescent, do not express MyoD family transcription factors or cell cycle regulatory genes and are insulated from the surrounding environment. Here, we report that the p38alpha/beta family of mitogen-activated protein kinases (MAPKs) reversibly regulates the quiescent state of the skeletal muscle satellite cell. Inhibition of p38alpha/beta MAPKs (a) promotes exit from the cell cycle, (b) prevents differentiation, and (c) insulates the cell from most external stimuli allowing the satellite cell to maintain a quiescent state. Activation of satellite cells and p38alpha/beta MAPKs occurs concomitantly, providing further support that these MAPKs function as a molecular switch for satellite cell activation. PMID:15824134

  12. Sorting single satellite cells from individual myofibers reveals heterogeneity in cell-surface markers and myogenic capacity.

    PubMed

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

    2013-04-01

    Traditional cell-screening techniques such as FACS and MACS are better suited for large numbers of cells isolated from bulk tissue and cannot easily screen stem or progenitor cells from minute populations found in their physiological niches. Furthermore, these techniques rely upon irreversible antibody binding, potentially altering cell properties, including gene expression and regenerative capacity. To address these challenges, we have developed a novel, label-free stem-cell analysis and sorting platform capable of quantifying cell-surface marker expression of single functional organ stem cells directly isolated from their micro-anatomical niche. Using our unique platform, we have discovered a remarkable heterogeneity in both the regenerative capacity and expression of CXCR4, β1-integrin, Sca-1, M-cadherin, Syndecan-4, and Notch-1 in freshly isolated muscle stem (satellite) cells residing on different, single myofibers and have identified a small population of Sca-1(+)/Myf5(+) myogenic satellite cells. Our results demonstrate the utility of our single-cell platform for uncovering and functionally characterizing stem-cell heterogeneity in the organ microniche. PMID:23407661

  13. Regeneration of skeletal muscle fibers from autologous satellite cells multiplied in vitro. An experimental model for testing cultured cell myogenicity

    SciTech Connect

    Alameddine, H.S.; Dehaupas, M.; Fardeau, M. )

    1989-07-01

    An experimental model used to test in vivo myogenicity of autologous satellite cells multiplied in vitro is described. Free muscle autotransplantation served as the basis and was combined with x-irradiation. Administration of 1500, 2500, and 3500 rad doses 24 hours before or after ischemia showed that inhibition of spontaneous regeneration is dose dependent and more efficient when irradiation was applied before injury. A single dose of 2500 rad before injury resulted in the formation of a cystic structure ideal for cell implantation. FITC-latex beads and/or carbocyanine dyes were internalized by mononucleated satellite cells in vitro. Labeling did not affect survival or development of these cells. No sign of marker release or spreading from labeled to unlabeled cells was detectable unless by the fusion process. These labels were retained for several weeks. Grafting of labeled dense cellular suspensions into x-irradiated ischemic muscles indicated that satellite cells retain their myogenic characteristic and are able to reform fully differentiated muscle fibers. 55 references.

  14. Proliferative Dynamics and the Role of FGF2 During Myogenesis of Rat Satellite Cells on Isolated Fibers

    PubMed Central

    Yablonka-Reuveni, Zipora; Rivera, Anthony J.

    2015-01-01

    Myogenic precursors in adult skeletal muscle (satellite cells) are mitotically quiescent but can proliferate in response to a variety of stresses including muscle injury. To gain further understanding of adult myoblasts, we are analyzing myogenesis of satellite cells on fibers isolated from adult rat muscle. In this culture model, satellite cells are maintained in their in situ position underneath the fiber basement membrane. Employing two different approaches to monitor proliferation of satellite cells on isolated fibers (autoradiography following 3H-thymidine incorporation and immunofluorescence of cells positive for proliferating cell nuclear antigen (PCNA)), we show in the present study that satellite cells initiate cell proliferation at 12 to 24 hours following fiber culture establishment and that cell proliferation is reduced to minimal levels by 60 to 72 hours in culture. Maximal number of proliferating cells is seen at 36 to 48 hours in culture. These PCNA+ satellite cells transit into the differentiated, myogenin+ state following about 24 hours in the proliferative state. Continuous exposure of the fiber culture to FGF2 (basic FGF; added at the time of culture establishment) leads to a 2 fold increase in the number of PCNA+ cells by 48 hours in culture but the overall schedule of proliferation and transition into the myogenin+ state is not affected. Delaying the addition of FGF2 until 15 to 18 hours following the initiation of the fiber culture does not reduce its effect. However, the addition of FGF2 at 24 hours or later results in a progressive reduction in the number of proliferating satellite cells. Exposure of fiber cultures to transforming growth factor β (TGFβ1) leads to a reduction in the number of proliferating cells in both the absence or presence of FGF2. We propose that FGF2 enhances the number of proliferating cells by facilitating the recruitment of additional satellite cells from the quiescent state. However, satellite cells on isolated

  15. Hyperhomocysteinemia inhibits satellite cell regenerative capacity through p38 alpha/beta MAPK signaling.

    PubMed

    Veeranki, Sudhakar; Lominadze, David; Tyagi, Suresh C

    2015-07-15

    Chronic failure in maintenance and regeneration of skeletal muscles leads to lower muscle mass (sarcopenia), muscle weakness, and poor response to injury. Evidence suggests that aberrant p38 MAPK signaling undermines the repair process after injury in aged mice. Previous studies have shown that hyperhomocysteinemia (HHcy) has been associated with muscle weakness and lower than normal body weights. However, whether or not HHcy condition also compromises skeletal muscle regenerative capabilities is not clear. In the current study, we show that CBS-/+ mice, a model for HHcy condition, exhibited compromised regenerative function and cell proliferation upon injury. However, there was no significant difference in Pax7 expression levels in the satellite cells from CBS-/+ mouse skeletal muscles. Interestingly, the satellite cells from CBS-/+ mice not only exhibited diminished in vitro proliferative capabilities, but also there was heightened oxidative stress. In addition, there was enhanced p38 MAPK activation as well as p16 and p21 expression in the CBS-/+ mouse satellite cells. Moreover, the C2C12 myoblasts also exhibited higher p38 MAPK activation and p16 expression upon treatment with homocysteine in addition to enhanced ROS presence. Tissue engraftment potential and regeneration after injury were restored to some extent upon treatment with the p38-MAPK inhibitor, SB203580, in the CBS-/+ mice. These results together suggest that HHcy-induced diminished satellite cell proliferation involves excessive oxidative stress and p38 MAPK signaling. Our study further proposes that HHcy is a potential risk factor for elderly frailty, and need to be considered as a therapeutic target while designing the alleviation interventions/postinjury rehabilitation measures for adults with HHcy. PMID:25980021

  16. Myomir dysregulation and reactive oxygen species in aged human satellite cells.

    PubMed

    Di Filippo, Ester Sara; Mancinelli, Rosa; Pietrangelo, Tiziana; La Rovere, Rita Maria Laura; Quattrocelli, Mattia; Sampaolesi, Maurilio; Fulle, Stefania

    2016-04-29

    Satellite cells that reside on the myofibre surface are crucial for the muscle homeostasis and regeneration. Aging goes along with a less effective regeneration of skeletal muscle tissue mainly due to the decreased myogenic capability of satellite cells. This phenomenon impedes proper maintenance and contributes to the age-associated decline in muscle mass, known as sarcopenia. The myogenic potential impairment does not depend on a reduced myogenic cell number, but mainly on their difficulty to complete a differentiation program. The unbalanced production of reactive oxygen species in elderly people could be responsible for skeletal muscle impairments. microRNAs are conserved post-transcriptional regulators implicated in numerous biological processes including adult myogenesis. Here, we measure the ROS level and analyze myomiR (miR-1, miR-133b and miR-206) expression in human myogenic precursors obtained from Vastus lateralis of elderly and young subjects to provide the molecular signature responsible for the differentiation impairment of elderly activated satellite cells. PMID:26975470

  17. A Case of Extensive Wound Myiasis Caused by Lucilia sericata (Diptera: Calliphoridae) in a Patient with Maxillary Sinus Squamous Cell Carcinoma, in Turkey

    PubMed Central

    Demirel-Kaya, Filiz; Orkun, Ömer; Çakmak, Ayşe; İnkaya, A Çağkan; Öcal, Murat; Erguven, Sibel

    2016-01-01

    The larvae causing myiasis can lead extensive tissue destruction, invasion into deep tissues and secondary infections. Poor hygiene, low socioeconomic condition and presence of open wounds are the most important predisposing factors. This case report describes destructive wound myiasis in a 58-year-old male patient diagnosed with maxillary sinus squamous cell carcinoma who lives in a rural area in Ankara, Turkey. Approximately 200 larvae were collected and identified as Lucilia sericata by morphological examination. Myiasis should be considered especially when the patient has open extensive lesions such as malignant wounds. PMID:27308285

  18. Functional Myotube Formation from Adult Rat Satellite Cells in a Defined Serum-free System

    PubMed Central

    McAleer, Christopher W.; Rumsey, John W.; Stancescu, Maria; Hickman, James J.

    2016-01-01

    This manuscript describes the development of a culture system whereby mature contracting myotubes were formed from adult rat derived satellite cells. Satellite cells, extracted from the Tibialis Anterior (TA) of adult rats, were grown in defined serum-free growth and differentiation media, on a non-biological substrate, N-1[3-trimethoxysilyl propyl] diethylenetriamine. Myotubes were evaluated morphologically and immunocytochemically, using MyHC specific antibodies, as well as functionally using patch clamp electrophysiology to measure ion channel activity. Results indicated the establishment of the rapid expression of adult myosin isoforms that contrasts to their slow development in embryonic cultures. This culture system has applications in the understanding and treatment of age related muscle myopathy, muscular dystrophy, and for skeletal muscle engineering by providing a more relevant phenotype for both in vitro and in vivo applications. PMID:25683642

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

    PubMed

    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

    2016-01-01

    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. PMID:26987019

  20. Multi-temporal land cover classification of the Konya Basin, south-central Turkey, based on a LANDSAT TM-derived NDVI/NDMI time series: satellite remote sensing in support of landscape-scale soil biogeochemistry research

    NASA Astrophysics Data System (ADS)

    Mayes, M. T.; Ozdogan, M.; Marin-Spiotta, E.

    2010-12-01

    Recently, terrestrial biogeochemists and soil scientists have called for new approaches to study human impacts on soil biogeochemical properties at landscape-wide, 100-1000 km2 spatial scales (Trumbore and Czimczik 2008). Here, we use satellite remote sensing to map land cover across a 16,000 km2 region in the Konya Basin, south-central Turkey, in support of research into agricultural and pastoral land use impacts on soil biogeochemistry. Our land cover classification is based on time series analysis of Normalized Difference Vegetation Index (NDVI) and Normalized Difference Moisture Index (NDMI) data, derived from eight LANDSAT TM images spanning the 2006-2007 growing seasons. Using a hierarchical, binary-split classification approach and a support vector machine (SVM) algorithm, we map five land cover classes that correspond with the following dominant land-use categories: 1) annual cultivated row-crops, 2) perennial orchards/cultivated woody vegetation, 3) fallow fields, 4) uncultivated woody vegetation, 5) steppe vegetation/rangeland. The final map has an overall classification accuracy of 87.4% (kappa = 0.842), determined via traditional confusion-matrix analysis and over 150 site visits during summer 2010. Classes 1 and 2, which have the highest per-pixel NDVI and NDMI sums across image dates, attain the highest producer and consumer accuracies (>95%). We also compare the relative contributions and efficacy of NDVI and NDMI in separating land cover classes, and the influence of radiometric correction and calibration across image dates on classification accuracies. Our results support previous research showing that NDVI time series can effectively classify agricultural landscapes in semi-arid to arid environments (Simonneaux et al. 2008; Pax-Lenny et al. 1996). By combining our land cover map with other geospatial information in a GIS, we demonstrate how satellite remote sensing can help expand spatial scales of terrestrial biogeochemistry research from

  1. Lack of evidence for GDF11 as a rejuvenator of aged skeletal muscle satellite cells.

    PubMed

    Hinken, Aaron C; Powers, Janine M; Luo, Guizhen; Holt, Jason A; Billin, Andrew N; Russell, Alan J

    2016-06-01

    Recent high-profile studies report GDF11 to be a key circulating 'anti-aging' factor. However, a screen of extracellular proteins attempting to identify factors with 'anti-aging' phenotypes in aged murine skeletal muscle satellite cells did not identify GDF11 activity. We have been unable to confirm the reported activity of GDF11, similar to other laboratories offering conflicting data and describe our attempts to do so in this short take. PMID:27139744

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

    PubMed

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

    2016-01-01

    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. PMID:26743565

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

    PubMed

    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. PMID:27069062

  4. The effect of temperature on apoptosis and adipogenesis on skeletal muscle satellite cells derived from different muscle types

    PubMed Central

    Harding, Rachel L; Clark, Daniel L; Halevy, Orna; Coy, Cynthia S; Yahav, Shlomo; Velleman, Sandra G

    2015-01-01

    Satellite cells are multipotential stem cells that mediate postnatal muscle growth and respond differently to temperature based upon aerobic versus anaerobic fiber-type origin. The objective of this study was to determine how temperatures below and above the control, 38°C, affect the fate of satellite cells isolated from the anaerobic pectoralis major (p. major) or mixed fiber biceps femoris (b. femoris). At all sampling times, p. major and b. femoris cells accumulated less lipid when incubated at low temperatures and more lipid at elevated temperatures compared to the control. Satellite cells isolated from the p. major were more sensitive to temperature as they accumulated more lipid at elevated temperatures compared to b. femoris cells. Expression of adipogenic genes, CCAAT/enhancer-binding protein β (C/EBPβ) and proliferator-activated receptor gamma (PPARγ) were different within satellite cells isolated from the p. major or b. femoris. At 72 h of proliferation, C/EBPβ expression increased with increasing temperature in both cell types, while PPARγ expression decreased with increasing temperature in p. major satellite cells. At 48 h of differentiation, both C/EBPβ and PPARγ expression increased in the p. major and decreased in the b. femoris, with increasing temperature. Flow cytometry measured apoptotic markers for early apoptosis (Annexin-V-PE) or late apoptosis (7-AAD), showing less than 1% of apoptotic satellite cells throughout all experimental conditions, therefore, apoptosis was considered biologically not significant. The results support that anaerobic p. major satellite cells are more predisposed to adipogenic conversion than aerobic b. femoris cells when thermally challenged. PMID:26341996

  5. Fabrication of glass gas cells for the HALOE and MAPS satellite experiments

    NASA Technical Reports Server (NTRS)

    Sullivan, E. M.; Walthall, H. G.

    1984-01-01

    The Halogen Occultation Experiment (HALOE) and the Measurement of Air Pollution from Satellites (MAPS) experiment are satellite-borne experiments which measure trace constituents in the Earth's atmosphere. The instruments which obtain the data for these experiments are based on the gas filter correlation radiometer measurement technique. In this technique, small samples of the gases of interest are encapsulated in glass cylinders, called gas cells, which act as very selective optical filters. This report describes the techniques employed in the fabrication of the gas cells for the HALOE and MAPS instruments. Details of the method used to fuse the sapphire windows (required for IR transmission) to the glass cell bodies are presented along with detailed descriptions of the jigs and fixtures used during the assembly process. The techniques and equipment used for window inspection and for pairing the HALOE windows are discussed. Cell body materials and the steps involved in preparing the cell bodies for the glass-to-sapphire fusion process are given.

  6. Leucine Promotes Proliferation and Differentiation of Primary Preterm Rat Satellite Cells in Part through mTORC1 Signaling Pathway

    PubMed Central

    Dai, Jie-Min; Yu, Mu-Xue; Shen, Zhen-Yu; Guo, Chu-Yi; Zhuang, Si-Qi; Qiu, Xiao-Shan

    2015-01-01

    Signaling through the mammalian target of rapamycin (mTOR) in response to leucine modulates many cellular and developmental processes. However, in the context of satellite cell proliferation and differentiation, the role of leucine and mTORC1 is less known. This study investigates the role of leucine in the process of proliferation and differentiation of primary preterm rat satellite cells, and the relationship with mammalian target of rapamycin complex 1 (mTORC1) activation. Dissociation of primary satellite cells occurred with type I collagenase and trypsin, and purification, via different speed adherence methods. Satellite cells with positive expression of Desmin were treated with leucine and rapamycin. We observed that leucine promoted proliferation and differentiation of primary satellite cells and increased the phosphorylation of mTOR. Rapamycin inhibited proliferation and differentiation, as well as decreased the phosphorylation level of mTOR. Furthermore, leucine increased the expression of MyoD and myogenin while the protein level of MyoD decreased due to rapamycin. However, myogenin expressed no affect by rapamycin. In conclusion, leucine may up-regulate the activation of mTORC1 to promote proliferation and differentiation of primary preterm rat satellite cells. We have shown that leucine promoted the differentiation of myotubes in part through the mTORC1-MyoD signal pathway. PMID:26007333

  7. Sphingolipidoses in Turkey.

    PubMed

    Ozkara, Hatice Asuman; Topçu, Meral

    2004-09-01

    During the last 5 years 2057 children under the age of 5 with various neurologic symptoms with the suspected diagnosis of lysosomal storage diseases were referred to our hospital from different universities and state hospitals. We were able to separate sphingolipidoses by lysosomal enzyme screening. A total of 300 patients (15%) with sphingolipidoses were diagnosed; there were deficiencies of arylsulfatase A [metachromatic leukodystrophy (MLD)] in 93 (31%), hexosaminidase [Sandhoff disease (SHD)] in 62 (20.7%), hexosaminidase A [Tay-Sachs disease (TSD)] in 15 (5%), beta-galactosidase (GM1 gangliosidosis) in 35 (11.7%), alpha-galactosidase (Fabry disease) in one (0.3%) cerebroside beta-galactosidase (Krabbe disease) in 65 (21.7%) and glucosylceramidase (Gaucher disease) in 29 (9.6%). SHD (20.7%), MLD (31%) and Krabbe disease (21.7%) were common. Prenatal enzymatic diagnosis was made in 70 at risk pregnancies, 64 for TSD and SHD, three for MLD and three for GM1 gangliosidosis by using chorionic villus biopsy in 54, cord blood samples in 12 and cultured amniotic fluid cells in four. Seventeen fetuses were found to be affected. We have calculated the relative frequency and minimum incidence of sphingolipidoses in Turkey. The combined incidence of sphingolipidoses is 4.615 per 100,000 live births. The calculated incidences are 1.43, 0.95, 1, 0.23, 0.54, 0.45, 0.015 per 100,000 live births for MLD, SHD, Krabbe, Gaucher, TSD, GM1 gangliosidosis and Fabry diseases, respectively. The real incidence, which covers all subtypes of this group of diseases, should be greater than this number. The results suggested that, as a group, sphingolipidoses are relatively common and represent an important health problem in Turkey and some rare autosomal recessive diseases of Turkey are due to 'founder effect' created by consanguineous marriages. PMID:15275696

  8. Glutamate release from satellite glial cells of the murine trigeminal ganglion.

    PubMed

    Wagner, Lysann; Warwick, Rebekah A; Pannicke, Thomas; Reichenbach, Andreas; Grosche, Antje; Hanani, Menachem

    2014-08-22

    It has been proposed that glutamate serves as a mediator between neurons and satellite glial cells (SGCs) in sensory ganglia and that SGCs release glutamate. Using a novel method, we studied glutamate release from SGCs from murine trigeminal ganglia. Sensory neurons with adhering SGCs were enzymatically isolated from wild type and transgenic mice in which vesicular exocytosis was suppressed in glial cells. Extracellular glutamate was detected by microfluorimetry. After loading the cells with a photolabile Ca(2+) chelator, the intracellular Ca(2+) concentration was raised in SGCs by a UV pulse, which resulted in glutamate release. The amount of released glutamate was decreased in cells with suppressed exocytosis and after pharmacological block of hemichannels. The data demonstrate that SGCs of the trigeminal ganglion release glutamate in a Ca(2+)-dependent manner. PMID:24993296

  9. The role of radiation hard solar cells in minimizing the costs of global satellite communications systems

    NASA Astrophysics Data System (ADS)

    Summers, Geoffrey P.; Walters, Robert J.; Messenger, Scott R.; Burke, Edward A.

    1995-10-01

    An analysis embodied in a PC computer program is presented which quantitatively demonstrates how the availability of radiation hard solar cells can minimize the cost of a global satellite communication system. The chief distinction between the currently proposed systems, such as Iridium Odyssey and Ellipsat, is the number of satellites employed and their operating altitudes. Analysis of the major costs associated with implementing these systems shows that operation within the earth's radiation belts can reduce the total system cost by as much as a factor of two, so long as radiation hard components including solar cells, can be used. A detailed evaluation of several types of planar solar cells is given, including commercially available Si and GaAs/Ge cells, and InP/Si cells which are under development. The computer program calculates the end of life (EOL) power density of solar arrays taking into account the cell geometry, coverglass thickness, support frame, electrical interconnects, etc. The EOL power density can be determined for any altitude from low earth orbit (LEO) to geosynchronous (GEO) and for equatorial to polar planes of inclination. The mission duration can be varied over the entire range planned for the proposed satellite systems. An algorithm is included in the program for determining the degradation of cell efficiency for different cell technologies due to proton and electron irradiation. The program can be used to determine the optimum configuration for any cell technology for a particular orbit and for a specified mission life. Several examples of applying the program are presented, in which it is shown that the EOL power density of different technologies can vary by an order of magnitude for certain missions. Therefore, although a relatively radiation soft technology can be made to provide the required EOL power by simply increasing the size of the array, the impact on the total system budget could be unacceptable, due to increased launch and

  10. A Novel Approach to Collecting Satellite Cells From Adult Skeletal Muscles on the Basis of Their Stress Tolerance

    PubMed Central

    Kuroda, Yasumasa; Wakao, Shohei

    2013-01-01

    Stem cells are generally collected using flow cytometry, but this method is not applicable when the cell surface marker is not well determined. Satellite cells, which are skeletal muscle stem cells, have the ability to regenerate damaged muscles and are expected to be applicable for treatment of muscle degeneration. Although the transcription factor Pax7 is a known specific marker of satellite cells, it is not located on the cell surface and therefore flow cytometry is not directly applicable. In the present study, we turned our attention to the stress tolerance of adult stem cells, and we propose long-term trypsin incubation (LTT) as a novel approach to collecting satellite cells from mouse and human skeletal muscles. LTT led to a remarkable increase in the ratio of Pax7(+) cells that retain normal myogenic stem cell function. In particular, human Pax7(+) cells made up approximately 30% of primary cultured cells, whereas after LTT, the ratio of Pax7(+) cells increased up to ∼80%, and the ratio of Pax7(+) and/or MyoD(+) myogenic cells increased to ∼95%. Once transplanted, LTT-treated cells contributed to subsequent muscle regeneration following repetitive muscle damage without additional cell transplantation. The stress tolerance of Pax7(+) cells is related to heat shock protein 27 and αB-crystallin, members of the small heat shock protein family. This approach, based on the stress resistance of adult stem cells, is a safe and inexpensive method of efficiently collecting human satellite cells and may also be used for collecting other tissue stem cells whose surface marker is unknown. PMID:23748608

  11. MMP-14 is necessary but not sufficient for invasion of three-dimensional collagen by human muscle satellite cells

    PubMed Central

    Lund, Dane K.; Mouly, Vincent

    2014-01-01

    The twenty-five known matrix metalloproteases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteases (TIMPs), mediate cell invasion through the extracellular matrix (ECM). In a comparative three-dimensional assay, we analyzed human and mouse satellite cells' competence to invade an artificial ECM (collagen I). We identified a single MMP that 1) is expressed by human muscle satellite cells; 2) is induced at the mRNA/protein level by adhesion to collagen I; and 3) is necessary for invasion into a collagen I matrix. Interestingly, murine satellite cells neither express this MMP, nor invade the collagen matrix. However, exogenous human MMP-14 is not sufficient to induce invasion of a collagen matrix by murine cells, emphasizing species differences. PMID:24898588

  12. MMP-14 is necessary but not sufficient for invasion of three-dimensional collagen by human muscle satellite cells.

    PubMed

    Lund, Dane K; Mouly, Vincent; Cornelison, D D W

    2014-07-15

    The twenty-five known matrix metalloproteases (MMPs) and their endogenous inhibitors, tissue inhibitors of metalloproteases (TIMPs), mediate cell invasion through the extracellular matrix (ECM). In a comparative three-dimensional assay, we analyzed human and mouse satellite cells' competence to invade an artificial ECM (collagen I). We identified a single MMP that 1) is expressed by human muscle satellite cells; 2) is induced at the mRNA/protein level by adhesion to collagen I; and 3) is necessary for invasion into a collagen I matrix. Interestingly, murine satellite cells neither express this MMP, nor invade the collagen matrix. However, exogenous human MMP-14 is not sufficient to induce invasion of a collagen matrix by murine cells, emphasizing species differences. PMID:24898588

  13. Expressed Sequence Tags for Bovine Muscle Satellite Cells, Myotube Formed-Cells and Adipocyte-Like Cells

    PubMed Central

    Pokharel, Smritee; Malik, Adeel; Tareq, K. M. A.; Roouf Bhat, Abdul; Park, Hee-Bok; Lee, Yong Seok; Kim, SangHoon; Yang, Bohsuk; Young Chung, Ki; Choi, Inho

    2013-01-01

    Background Muscle satellite cells (MSCs) represent a devoted stem cell population that is responsible for postnatal muscle growth and skeletal muscle regeneration. An important characteristic of MSCs is that they encompass multi potential mesenchymal stem cell activity and are able to differentiate into myocytes and adipocytes. To achieve a global view of the genes differentially expressed in MSCs, myotube formed-cells (MFCs) and adipocyte-like cells (ALCs), we performed large-scale EST sequencing of normalized cDNA libraries developed from bovine MSCs. Results A total of 24,192 clones were assembled into 3,333 clusters, 5,517 singletons and 3,842contigs. Functional annotation of these unigenes revealed that a large portion of the differentially expressed genes are involved in cellular and signaling processes. Database for Annotation, Visualization and Integrated Discovery (DAVID) functional analysis of three subsets of highly expressed gene lists (MSC233, MFC258, and ALC248) highlighted some common and unique biological processes among MSC, MFC and ALC. Additionally, genes that may be specific to MSC, MFC and ALC are reported here, and the role of dimethylarginine dimethylaminohydrolase2 (DDAH2) during myogenesis and hemoglobin subunit alpha2 (HBA2) during transdifferentiation in C2C12 were assayed as a case study. DDAH2 was up-regulated during myognesis and knockdown of DDAH2 by siRNA significantly decreased myogenin (MYOG) expression corresponding with the slight change in cell morphology. In contrast, HBA2 was up-regulated during ALC formation and resulted in decreased intracellular lipid accumulation and CD36 mRNA expression upon knockdown assay. Conclusion In this study, a large number of EST sequences were generated from the MSC, MFC and ALC. Overall, the collection of ESTs generated in this study provides a starting point for the identification of novel genes involved in MFC and ALC formation, which in turn offers a fundamental resource to enable better

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

    NASA Technical Reports Server (NTRS)

    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.

  15. Rat soleus muscle satellite cells during the recovery after gravitational unloading

    NASA Astrophysics Data System (ADS)

    Turtikova, Olga; Shenkman, Boris; Altaeva, Erzhena; Leinsoo, Toomas

    In this study the attempt was made to assess alterations of rat soleus satellite cell (SC) population during muscle regrowth after 14-day gravitational unloading (using the hindlimb suspension model). Myofiber size increases during the recovery period. SCs are supposed to participate in muscle growth by fusion with myofibers and supplying them with new myonuclei [Mitchell PO, Pavlath GK, 2001; Oishi Y., 2008]. Other points of view are known about SC participation in the recovery of atrophied muscle mass during the readaptation period [Bruusgaard J.C. et al., 2011; Jackson JR et al., 2012]. After 2 weeks of hindlimb suspension mki67 expression was fivefold lower as compared to control animals and increased gradually up to 28 times by the day 7 of reloading. Cdh15 was decreased after hindlimb unloading and rose from the 1st day of reloading. The expression reached control level to the day 7th of reloading. Cellular response was going on concurrently with the spike of IGF-1 blood level and the increase in muscle IGF-1 concentration. It is possible that in the early days of reloading period differentiation and fusion of satellite cells which were active by the end of hindlimb suspension occurred. Satellite cell incorporation was assessed by counting the amount of BrdU+ myonuclei under myofiber dystrophin layer. It came more intensively in the 1st day of readaptation. It is in accordance with the 4,5 time increase in myogenin expression as compared to hindlimb suspended animals detected at the same time point. Myogenin expression 3 fold decreased by 3rd day of readaptation. We observed only the tendency of resizing but no significant changes in in myonuclear domain size. The number of myonuclei per myofiber cross section was decreased after hindlimb suspension and was not restored by the day 14th of readaptation. Cdh15 and myogenin expression at some extent stabilized after 7 days of readaptation, but high mki67 level pointed to intensive proliferation, which could

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

    NASA Technical Reports Server (NTRS)

    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.

  17. Spiral ganglion degeneration and hearing loss as a consequence of satellite cell death in saposin B-deficient mice.

    PubMed

    Akil, Omar; Sun, Ying; Vijayakumar, Sarath; Zhang, Wujuan; Ku, Tiffany; Lee, Chi-Kyou; Jones, Sherri; Grabowski, Gregory A; Lustig, Lawrence R

    2015-02-18

    Saposin B (Sap B) is an essential activator protein for arylsulfatase A in the hydrolysis of sulfatide, a lipid component of myelin. To study Sap B's role in hearing and balance, a Sap B-deficient (B(-/-)) mouse was evaluated. At both light and electron microscopy (EM) levels, inclusion body accumulation was seen in satellite cells surrounding spiral ganglion (SG) neurons from postnatal month 1 onward, progressing into large vacuoles preceding satellite cell degeneration, and followed by SG degeneration. EM also revealed reduced or absent myelin sheaths in SG neurons from postnatal month 8 onwards. Hearing loss was initially seen at postnatal month 6 and progressed thereafter for frequency-specific stimuli, whereas click responses became abnormal from postnatal month 13 onward. The progressive hearing loss correlated with the accumulation of inclusion bodies in the satellite cells and their subsequent degeneration. Outer hair cell numbers and efferent function measures (distortion product otoacoustic emissions and contralateral suppression) were normal in the B(-/-) mice throughout this period. Alcian blue staining of SGs demonstrated that these inclusion bodies corresponded to sulfatide accumulation. In contrast, changes in the vestibular system were much milder, but caused severe physiologic deficits. These results demonstrate that loss of Sap B function leads to progressive sulfatide accumulation in satellite cells surrounding the SG neurons, leading to satellite cell degeneration and subsequent SG degeneration with a resultant loss of hearing. Relative sparing of the efferent auditory and vestibular neurons suggests that alternate glycosphingolipid metabolic pathways predominate in these other systems. PMID:25698761

  18. Assaying Human Myogenic Progenitor Cell Activity by Reconstitution of Muscle Fibers and Satellite Cells in Immunodeficient Mice.

    PubMed

    Parker, Maura H

    2016-01-01

    Comparing the functional myogenic potential of various human cell populations is an important step in the preclinical evaluation of cell transplantation as a means to treat human muscle disease and degeneration. Culture systems allow one to gage the potential of cell populations to proliferate and undergo myogenic differentiation under specific conditions. An in vivo assay evaluates the ability of cells to differentiate and generate muscle fibers within a natural environment, and importantly, evaluates the potential of donor cells to reconstitute the satellite cell niche. In this chapter, we describe a technique for isolating mononuclear cells from human muscle samples, and a method of xenotransplantation for assessing functional myogenic potential in vivo. Briefly, cell populations are injected into the pre-irradiated and regenerating muscle of immunodeficient mice. The injected muscle is frozen at specific time points after injection and cryosections analyzed by immunostaining. The number of human dystrophin-expressing fibers and the number of Pax7(+) human lamin A/C(+) nuclei are determined, which provides a quantitative method of comparing the in vivo functional potential of cell populations. PMID:27492175

  19. Developmental stage determines efficiency of gene transfer to muscle satellite cells by in utero delivery of adeno-associated virus vector serotype 2/9.

    PubMed

    Stitelman, David H; Brazelton, Tim; Bora, Archana; Traas, Jeremy; Merianos, Demetri; Limberis, Maria; Davey, Marcus; Flake, Alan W

    2014-01-01

    Efficient gene transfer to muscle stem cells (satellite cells) has not been achieved despite broad transduction of skeletal muscle by systemically administered adeno-associated virus serotype 2/9 (AAV-9) in mice. We hypothesized that cellular migration during fetal development would make satellite cells accessible for gene transfer following in utero intravascular injection. We injected AAV-9 encoding green fluorescent protein (GFP) marker gene into the vascular space of mice ranging in ages from post-coital day 12 (E12) to postnatal day 1 (P1). Satellite cell transduction was examined using: immunohistochemistry and confocal microscopy, satellite cell migration assay, myofiber isolation and FACS analysis. GFP positive myofibers were detected in all mature skeletal muscle groups and up to 100% of the myofibers were transduced. We saw gestational variation in cardiac and skeletal muscle expression. E16 injection resulted in 27.7 ± 10.0% expression in satellite cells, which coincides with the timing of satellite cell migration, and poor satellite cell expression before and after satellite cell migration (E12 and P1). Our results demonstrate that efficient gene expression is achieved in differentiated myofibers and satellite cells after injection of AAV-9 in utero. These findings support the potential of prenatal gene transfer for muscle based treatment strategies. PMID:26015979

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

    PubMed Central

    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

    2016-01-01

    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. DOI: http://dx.doi.org/10.7554/eLife.12116.001 PMID:26987019

  1. Isolation of Nuclei from Skeletal Muscle Satellite Cells and Myofibers for Use in Chromatin lmmunoprecipitation Assays

    PubMed Central

    Ohkawa, Yasuyuki; Mallappa, Chandrashekara; Dacwag Vallaster, Caroline S.; lmbalzano, Anthony N.

    2014-01-01

    Studies investigating mechanisms controlling gene regulation frequently examine specific DNA sequences using chromatin immunoprecipitation (ChIP) assays to determine whether specific regulatory factors or modified histones are present. While use of primary cells or cell line models for differentiating or differentiated tissue is widespread, the ability to assess factor binding and histone modification in tissue defines the events that occur in vivo and provides corroboration for studies in cultured cells. Many tissues can be analyzed with minimal modification to existing ChIP protocols that are designed for cultured cells; however, some tissues, such as skeletal muscle, are problematic in that accessibility of the cross-linking agent is limited. We describe a method to isolate skeletal muscle tissue nuclei suitable for use in ChIP protocols. Furthermore, we utilize a simple fractionation of digested skeletal muscle tissue that can separate mature myofibers from satellite cells, which are responsible for postnatal skeletal muscle regeneration, thereby allowing simultaneous preparation of nuclei from both cell types. PMID:22130858

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

    PubMed Central

    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. PMID:26884682

  3. Natural infection of turkeys by infectious laryngotracheitis virus.

    PubMed

    Portz, Cristiana; Beltrão, Nilzane; Furian, Thales Quedi; Júnior, Alfredo Bianco; Macagnan, Marisa; Griebeler, Josiane; Lima Rosa, Carlos André Veiga; Colodel, Edson Moleta; Driemeier, David; Back, Alberto; Barth Schatzmayr, Ortrud Monika; Canal, Cláudio Wageck

    2008-09-18

    The infectious laryngotracheitis virus (ILTV) is an important respiratory pathogen of chickens that also infects pheasants and peafowl. Epidemiologically non-related commercial turkey flocks with clinical signs such as tracheitis, swollen sinuses, conjunctivitis and expectoration of bloody mucus were examined for the presence of the virus. Laboratory ILTV detection was performed by virus isolation in embryonated eggs and cell cultures, PCR and sequencing of amplification products, histopathology, indirect immunofluorescence and electron microscopy. One ILTV turkey isolate was also experimentally inoculated into susceptible chickens and turkeys, reproducing a mild respiratory disease. This is the first description of natural infections with ILTV in turkeys. PMID:18436397

  4. Satellite cells isolated from skeletal muscle will proliferate faster in WENS yellow feather chicks.

    PubMed

    Gao, Chun-Qi; Zhang, Hao-Jie; Yan, Hui-Chao; Yuan, Li; Dahanayaka, Sudath; Li, Hai-Chang; Wang, Xiu-Qi

    2016-01-01

    This study was conducted to evaluate the differential proliferation ability of satellite cells (SCs) derived from pectoral muscles (PM) with different fiber characteristics and further to explore the underlying molecular mechanism. WENS Yellow Feather Chicks (WYFC) were chosen as the animal model, with White Plymouth Rock Chicks (WPRC) as a comparison. The results showed that WPRC had higher body and pectoral muscle weight than WYFC at 4 days old (P < 0.05). However, WYFC showed greater fiber numbers/mm(2) but smaller fiber cross-sectional area compared with WPRC in PM (P < 0.05). SCs derived from PM of WYFC had a faster proliferation rate but smaller cell size compared with that from PM of WPRC (P < 0.05). The percentage of cell population in G2/M phase and the messenger RNA abundance of TSC1 (P = 0.08), Rheb (P = 0.07) and target of rapamycin (TOR, P = 0.06) in WYFC were higher than that in WPRC. In conclusion, our results demonstrated that SCs isolated from PM of WYFC had faster proliferation rate but smaller cell size than that in WPRC. The higher SC proliferation in WYFC may be due to higher gene expression of TOR signaling pathway than in WPRC, and the larger cell size of WPRC may be due to higher insulin-like growth factor-1 expression than in WYFC. PMID:26248947

  5. KLF7 Regulates Satellite Cell Quiescence in Response to Extracellular Signaling.

    PubMed

    Wang, Xiaobin; Shen, Qingwu W; Wang, Jie; Zhang, Zhiguo; Feng, Fu; Chen, Ting; Zhang, Yanyan; Wei, Huan; Li, Zhongwen; Wang, Xinxia; Wang, Yizhen

    2016-05-01

    Retaining muscle stem satellite cell (SC) quiescence is important for the maintenance of stem cell population and tissue regeneration. Accumulating evidence supports the model where key extracellular signals play crucial roles in maintaining SC quiescence or activation, however, the intracellular mechanisms that mediate niche signals to control SC behavior are not fully understood. Here, we reported that KLF7 functioned as a key mediator involved in low-level TGF-β signaling and canonical Notch signaling-induced SC quiescence and myoblast arrest. The data obtained showed that KLF7 was upregulated in quiescent SCs and nonproliferating myoblasts. Silence of KLF7 promoted SCs activation and myoblasts proliferation, but overexpression of KLF7 induced myogenic cell arrest. Notably, the expression of KLF7 was regulated by TGF-β and Notch3 signaling. Knockdown of KLF7 diminished low-level TGF-β and canonical Notch signaling-induced SC quiescence. Investigation into the mechanism revealed that KLF7 regulation of SC function was dependent on p21 and acetylation of Lys227 and/or 231 in the DNA binding domain of KLF7. Our study provides new insights into the regulatory network of muscle stem cell quiescence. Stem Cells 2016;34:1310-1320. PMID:26930448

  6. Dual role of the caspase enzymes in satellite cells from aged and young subjects.

    PubMed

    Fulle, S; Sancilio, S; Mancinelli, R; Gatta, V; Di Pietro, R

    2013-01-01

    Satellite cell (SC) proliferation and differentiation have critical roles in skeletal muscle recovery after injury and adaptation in response to hypertrophic stimuli. Normal ageing hinders SC proliferation and differentiation, and is associated with increased expression of a number of pro-apoptotic factors in skeletal muscle. In light of previous studies that have demonstrated age-related altered expression of genes involved in SC antioxidant and repair activity, this investigation was aimed at evaluating the incidence of apoptotic features in human SCs. Primary cells were obtained from vastus lateralis of nine young (27.3±2.0 years old) and nine old (71.1±1.8 years old) subjects, and cultured in complete medium for analyses at 4, 24, 48, and 72 h. Apoptosis was assessed using AnnexinV/propidium iodide staining, the terminal deoxynucleotidyl transferase dUTP nick-end labelling technique, RT-PCR, DNA microarrays, flow cytometry, and immunofluorescence analysis. There was an increased rate of apoptotic cells in aged subjects at all of the experimental time points, with no direct correlation between AnnexinV-positive cells and caspase-8 activity. On the other hand, CASP2, CASP6, CASP7, and CASP9 and a number of cell death genes were upregulated in the aged SCs. Altogether, our data show age-related enhanced susceptibility of human SCs to apoptosis, which might be responsible for their reduced response to muscle damage. PMID:24336075

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

    PubMed

    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. PMID:26739770

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

    PubMed

    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. PMID:25571987

  9. Do the Purkinje cells have a special type of oligodendrocyte as satellites?

    PubMed Central

    Monteiro, R A

    1983-01-01

    Two types of oligodendrocytes considered to be a constant feature in the cerebellar cortex of the rat are described. One cell type (I) exhibits rounded or elliptical nuclei, whereas the other type (II) presents more irregular nuclear and cellular contours and wider perinuclear cisternae. The latter cell type shows a more electron-dense cytoplasm with more heavily clumped heterochromatin, contrasting strongly with the euchromatin; also long and parallel cisternae of rough endoplasmic reticulum are more frequent. The percentages of both types of oligodendrocytes in relation to the total population of common glial cell types were calculated in the cortical layers and at several levels in these layers. The distribution of oligodendrocytes in the associated white matter was also carried out for purposes of comparison. The results provide evidence the the Purkinje cells may have a special kind of oligodendrocyte (Type II) as satellites. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 PMID:6630036

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Sodium and potassium currents in freshly isolated and in proliferating human muscle satellite cells.

    PubMed Central

    Hamann, M; Widmer, H; Baroffio, A; Aubry, J P; Krause, R M; Kaelin, A; Bader, C R

    1994-01-01

    1. Human muscle satellite cells (SC) were studied either immediately after dissociation of muscle biopsies or later, as they proliferated in culture. A purification procedure combined with clonal cultures ensured that electrophysiological recordings were done in myogenic cells. Hoechst staining for the DNA attested that cells were mononucleated. 2. The goals of this study were to examine (i) whether the electrophysiological properties of freshly isolated SC resembled those of SC that proliferated in culture for several weeks, (ii) whether freezing and thawing affected these properties, and (iii) whether SC constituted a homogeneous population. 3. We found that there were only subtle differences between the electrophysiological results obtained in freshly isolated SC and in proliferating SC with or without previous freezing and thawing. Most SC expressed two voltage-gated currents, a TTX-resistant Na+ current and a calcium-activated potassium current (IK, Ca). 4. The level of expression of the Na+ current and of IK, Ca was affected in a different way by cellular proliferation; the normalized Na+ conductance (pS pF-1) of proliferating cells resembled that of freshly isolated SC, whereas the IK, Ca conductance increased 10 times. The analysis of the amplitude distributions of the Na+ current and of IK, Ca in the various SC preparations suggested that there was only one class of SC. PMID:8021836

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

    PubMed

    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. PMID:27583644

  13. Sequence-specific microscopic visualization of DNA methylation status at satellite repeats in individual cell nuclei and chromosomes

    PubMed Central

    Li, Yufeng; Miyanari, Yusuke; Shirane, Kenjiro; Nitta, Hirohisa; Kubota, Takeo; Ohashi, Hirofumi; Okamoto, Akimitsu; Sasaki, Hiroyuki

    2013-01-01

    Methylation-specific fluorescence in situ hybridization (MeFISH) was developed for microscopic visualization of DNA methylation status at specific repeat sequences in individual cells. MeFISH is based on the differential reactivity of 5-methylcytosine and cytosine in target DNA for interstrand complex formation with osmium and bipyridine-containing nucleic acids (ICON). Cell nuclei and chromosomes hybridized with fluorescence-labeled ICON probes for mouse major and minor satellite repeats were treated with osmium for crosslinking. After denaturation, fluorescent signals were retained specifically at satellite repeats in wild-type, but not in DNA methyltransferase triple-knockout (negative control) mouse embryonic stem cells. Moreover, using MeFISH, we successfully detected hypomethylated satellite repeats in cells from patients with immunodeficiency, centromeric instability and facial anomalies syndrome and 5-hydroxymethylated satellite repeats in male germ cells, the latter of which had been considered to be unmethylated based on anti-5-methylcytosine antibody staining. MeFISH will be suitable for a wide range of applications in epigenetics research and medical diagnosis. PMID:23990328

  14. Sequence-specific microscopic visualization of DNA methylation status at satellite repeats in individual cell nuclei and chromosomes.

    PubMed

    Li, Yufeng; Miyanari, Yusuke; Shirane, Kenjiro; Nitta, Hirohisa; Kubota, Takeo; Ohashi, Hirofumi; Okamoto, Akimitsu; Sasaki, Hiroyuki

    2013-10-01

    Methylation-specific fluorescence in situ hybridization (MeFISH) was developed for microscopic visualization of DNA methylation status at specific repeat sequences in individual cells. MeFISH is based on the differential reactivity of 5-methylcytosine and cytosine in target DNA for interstrand complex formation with osmium and bipyridine-containing nucleic acids (ICON). Cell nuclei and chromosomes hybridized with fluorescence-labeled ICON probes for mouse major and minor satellite repeats were treated with osmium for crosslinking. After denaturation, fluorescent signals were retained specifically at satellite repeats in wild-type, but not in DNA methyltransferase triple-knockout (negative control) mouse embryonic stem cells. Moreover, using MeFISH, we successfully detected hypomethylated satellite repeats in cells from patients with immunodeficiency, centromeric instability and facial anomalies syndrome and 5-hydroxymethylated satellite repeats in male germ cells, the latter of which had been considered to be unmethylated based on anti-5-methylcytosine antibody staining. MeFISH will be suitable for a wide range of applications in epigenetics research and medical diagnosis. PMID:23990328

  15. Analytic studies on satellite detection of severe, two-cell tornadoes

    NASA Technical Reports Server (NTRS)

    Carrier, G. F.; Dergarabedian, P.; Fendell, F. E.

    1979-01-01

    From funnel-cloud-length interpretation, the severe tornado is characterized by peak swirl speed relative to the axis of rotation of about 90 m/s. Thermohydrodynamic achievement of the pressure deficit from ambient necessary to sustain such swirls requires that a dry, compressionally heated, non-rotating downdraft of initially tropopause-level air lie within an annulus of rapidly swirling, originally low-level air ascending on a near-moist-adiabatic locus of thermodynamic states. The two-cell structure furnishes an observable parameter possibly accessible to a passively instrumented, geosynchronous meteorological satellite with mesoscale resolution, for early detection of a severe tornado. Accordingly, the low-level turnaround region, in which the surface inflow layer separates to become a free ascending layer and for which inviscid modeling suffices, is examined quantitatively. Preliminary results indicate that swirl overshoot, i.e., swirl speeds in the turnaround region in excess of the maximum achieved in the potential vortex, is modest.

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

    PubMed Central

    Biressi, Stefano; Gopinath, Suchitra D.

    2015-01-01

    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 (SCs), have recently become the focus of several studies examining factors participating in the atrophic process. We critically examine here the experimental evidence linking SC 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 SCs in terms of their differentiation and proliferative capacity in response to various atrophic stimuli. In this regard, we review the molecular changes within SCs 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. PMID:26257645

  17. Adult Education in Turkey

    ERIC Educational Resources Information Center

    Miser, Rifat; Ural, Ozana; Ünlühisarýklý, Özlem

    2013-01-01

    This study investigates the situation and practices of adult education in Turkey in terms of (a) participants, (b) providers, and (c) program areas. The data were derived from published statistical data and one-to-one interaction with adult education providers when such data are unavailable. Turkey has a long tradition of adult education with…

  18. A single bout of exercise activates skeletal muscle satellite cells during subsequent overnight recovery.

    PubMed

    Snijders, Tim; Verdijk, Lex B; Beelen, Milou; McKay, Bryon R; Parise, Gianni; Kadi, Fawzi; van Loon, Luc J C

    2012-06-01

    Skeletal muscle satellite cell (SC) content has been reported to increase following a single bout of exercise. Data on muscle fibre type-specific SC content and/or SC activation status are presently lacking. The objective of the study was to determine the impact of a single bout of exercise on muscle fibre type-specific SC content and activation status following subsequent overnight recovery. Eight healthy men (age, 20 ± 1 years) performed a single bout of combined endurance- and resistance-type exercise. Muscle biopsies were collected before and immediately after exercise, and following 9 h of postexercise, overnight recovery. Muscle fibre type-specific SC and myonuclear content and SC activation status were determined by immunohistochemical analyses. Satellite cell activation status was assessed by immunohistochemical staining for both Delta-like homologue 1 (DLK1) and Ki-67. Muscle fibre size and fibre area per nucleus were greater in type II compared with type I muscle fibres (P < 0.05). At baseline, no differences were observed in the percentage of SCs staining positive for DLK1 and/or Ki67 between fibre types. No significant changes were observed in SC content following 9 h of postexercise, overnight recovery; however, the percentage of DLK1-positive SCs increased significantly during overnight recovery, from 22 ± 5 to 41 ± 5% and from 24 ± 6 to 51 ± 9% in the type I and II muscle fibres, respectively. No changes were observed in the percentage of Ki-67-positive SCs. A single bout of exercise activates both type I and II skeletal muscle fibre SCs within a single night of postexercise recovery, preceding the subsequent increase in SC content. PMID:22327327

  19. Centriolar Satellites

    PubMed Central

    Kubo, Akiharu; Sasaki, Hiroyuki; Yuba-Kubo, Akiko; Tsukita, Shoichiro; Shiina, Nobuyuki

    1999-01-01

    We identified Xenopus pericentriolar material-1 (PCM-1), which had been reported to constitute pericentriolar material, cloned its cDNA, and generated a specific pAb against this molecule. Immunolabeling revealed that PCM-1 was not a pericentriolar material protein, but a specific component of centriolar satellites, morphologically characterized as electron-dense granules, ∼70–100 nm in diameter, scattered around centrosomes. Using a GFP fusion protein with PCM-1, we found that PCM-1–containing centriolar satellites moved along microtubules toward their minus ends, i.e., toward centrosomes, in live cells, as well as in vitro reconstituted asters. These findings defined centriolar satellites at the molecular level, and explained their pericentriolar localization. Next, to understand the relationship between centriolar satellites and centriolar replication, we examined the expression and subcellular localization of PCM-1 in ciliated epithelial cells during ciliogenesis. When ciliogenesis was induced in mouse nasal respiratory epithelial cells, PCM-1 immunofluorescence was markedly elevated at the apical cytoplasm. At the electron microscopic level, anti–PCM-1 pAb exclusively labeled fibrous granules, but not deuterosomes, both of which have been suggested to play central roles in centriolar replication in ciliogenesis. These findings suggested that centriolar satellites and fibrous granules are identical novel nonmembranous organelles containing PCM-1, which may play some important role(s) in centriolar replication. PMID:10579718

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

    PubMed Central

    Randolph, Matthew E.; 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 (MDs), 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 MDs. The biology of muscle stem cells varies depending on 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. PMID:26500547

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

    NASA Astrophysics Data System (ADS)

    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.

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

    PubMed

    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 < 0.05) in all exercised groups. Proximal E2 replacement resulted in a further augmentation of muscle satellite cells in exercised rats (p < 0.05) relative to the delayed 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. PMID:26406298

  3. Izmit, Turkey 1999 Earthquake Interferogram

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This image is an interferogram that was created using pairs of images taken by Synthetic Aperture Radar (SAR). The images, acquired at two different times, have been combined to measure surface deformation or changes that may have occurred during the time between data acquisition. The images were collected by the European Space Agency's Remote Sensing satellite (ERS-2) on 13 August 1999 and 17 September 1999 and were combined to produce these image maps of the apparent surface deformation, or changes, during and after the 17 August 1999 Izmit, Turkey earthquake. This magnitude 7.6 earthquake was the largest in 60 years in Turkey and caused extensive damage and loss of life. Each of the color contours of the interferogram represents 28 mm (1.1 inches) of motion towards the satellite, or about 70 mm (2.8 inches) of horizontal motion. White areas are outside the SAR image or water of seas and lakes. The North Anatolian Fault that broke during the Izmit earthquake moved more than 2.5 meters (8.1 feet) to produce the pattern measured by the interferogram. Thin red lines show the locations of fault breaks mapped on the surface. The SAR interferogram shows that the deformation and fault slip extended west of the surface faults, underneath the Gulf of Izmit. Thick black lines mark the fault rupture inferred from the SAR data. Scientists are using the SAR interferometry along with other data collected on the ground to estimate the pattern of slip that occurred during the Izmit earthquake. This then used to improve computer models that predict how this deformation transferred stress to other faults and to the continuation of the North Anatolian Fault, which extends to the west past the large city of Istanbul. These models show that the Izmit earthquake further increased the already high probability of a major earthquake near Istanbul.

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

    PubMed

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

    2016-07-01

    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

  5. Clonal Characterization of Rat Muscle Satellite Cells: Proliferation, Metabolism and Differentiation Define an Intrinsic Heterogeneity

    PubMed Central

    Rossi, Carlo A.; Pozzobon, Michela; Ditadi, Andrea; Archacka, Karolina; Gastaldello, Annalisa; Sanna, Marta; Franzin, Chiara; Malerba, Alberto; Milan, Gabriella; Cananzi, Mara; Schiaffino, Stefano; Campanella, Michelangelo; Vettor, Roberto; De Coppi, Paolo

    2010-01-01

    Satellite cells (SCs) represent a distinct lineage of myogenic progenitors responsible for the postnatal growth, repair and maintenance of skeletal muscle. Distinguished on the basis of their unique position in mature skeletal muscle, SCs were considered unipotent stem cells with the ability of generating a unique specialized phenotype. Subsequently, it was demonstrated in mice that opposite differentiation towards osteogenic and adipogenic pathways was also possible. Even though the pool of SCs is accepted as the major, and possibly the only, source of myonuclei in postnatal muscle, it is likely that SCs are not all multipotent stem cells and evidences for diversities within the myogenic compartment have been described both in vitro and in vivo. Here, by isolating single fibers from rat flexor digitorum brevis (FDB) muscle we were able to identify and clonally characterize two main subpopulations of SCs: the low proliferative clones (LPC) present in major proportion (∼75%) and the high proliferative clones (HPC), present instead in minor amount (∼25%). LPC spontaneously generate myotubes whilst HPC differentiate into adipocytes even though they may skip the adipogenic program if co-cultured with LPC. LPC and HPC differ also for mitochondrial membrane potential (ΔΨm), ATP balance and Reactive Oxygen Species (ROS) generation underlying diversities in metabolism that precede differentiation. Notably, SCs heterogeneity is retained in vivo. SCs may therefore be comprised of two distinct, though not irreversibly committed, populations of cells distinguishable for prominent differences in basal biological features such as proliferation, metabolism and differentiation. By these means, novel insights on SCs heterogeneity are provided and evidences for biological readouts potentially relevant for diagnostic purposes described. PMID:20049087

  6. Dnmt3a Regulates Proliferation of Muscle Satellite Cells via p57Kip2

    PubMed Central

    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. The solar maximum satellite capture cell: Impact features and orbital debris and micrometeoritic projectile materials

    NASA Technical Reports Server (NTRS)

    Mckay, D. S.; Rietmeijer, F. J. M.; Schramm, L. S.; Barrett, R. A.; Zook, H. A.; Blanford, G. E.

    1986-01-01

    The physical properties of impact features observed in the Solar Max main electronics box (MEB) thermal blanket generally suggest an origin by hypervelocity impact. The chemistry of micrometeorite material suggests that a wide variety of projectile materials have survived impact with retention of varying degrees of pristinity. Impact features that contain only spacecraft paint particles are on average smaller than impact features caused by micrometeorite impacts. In case both types of materials co-occur, it is belevied that the impact feature, generally a penetration hole, was caused by a micrometeorite projectile. The typically smaller paint particles were able to penetrate though the hole in the first layer and deposit in the spray pattern on the second layer. It is suggested that paint particles have arrived with a wide range of velocities relative to the Solar Max satellite. Orbiting paint particles are an important fraction of materials in the near-Earth environment. In general, the data from the Solar Max studies are a good calibration for the design of capture cells to be flown in space and on board Space Station. The data also suggest that development of multiple layer capture cells in which the projectile may retain a large degree of pristinity is a feasible goal.

  8. Satellite glial cells in dorsal root ganglia are activated in streptozotocin-treated rodents

    PubMed Central

    Hanani, Menachem; Blum, Erez; Liu, Shuangmei; Peng, Lichao; Liang, Shangdong

    2014-01-01

    Neuropathic pain is a very common complication in diabetes mellitus (DM), and treatment for it is limited. As DM is becoming a global epidemic it is important to understand and treat this problem. The mechanisms of diabetic neuropathic pain are largely obscure. Recent studies have shown that glial cells are important for a variety of neuropathic pain types, and we investigated what are the changes that satellite glial cells (SGCs) in dorsal root ganglia undergo in a DM type 1 model, induced by streptozotocin (STZ) in mice and rats. We carried out immunohistochemical studies to learn about changes in the activation marker glial fibrillary acidic protein (GFAP) in SGCs. We found that after STZ-treatment the number of neurons surrounded with GFAP-positive SGCs in dorsal root ganglia increased 4-fold in mice and 5-fold in rats. Western blotting for GFAP, which was done only on rats because of the larger size of the ganglia, showed an increase of about 2-fold in STZ-treated rats, supporting the immunohistochemical results. These results indicate for the first time that SGCs are activated in rodent models of DM1. As SGC activation appears to contribute to chronic pain, these results suggest that SGCs may participate in the generation and maintenance of diabetic neuropathic pain, and can serve as a potential therapeutic target. PMID:25312986

  9. Caspase 3 cleavage of Pax7 inhibits self-renewal of satellite cells

    PubMed Central

    Dick, Sarah A.; Chang, Natasha C.; Dumont, Nicolas A.; Bell, Ryan A. V.; Putinski, Charis; Kawabe, Yoichi; Litchfield, David W.; Rudnicki, Michael A.; Megeney, Lynn A.

    2015-01-01

    Compensatory growth and regeneration of skeletal muscle is dependent on the resident stem cell population, satellite cells (SCs). Self-renewal and maintenance of the SC niche is coordinated by the paired-box transcription factor Pax7, and yet continued expression of this protein inhibits the myoblast differentiation program. As such, the reduction or removal of Pax7 may denote a key prerequisite for SCs to abandon self-renewal and acquire differentiation competence. Here, we identify caspase 3 cleavage inactivation of Pax7 as a crucial step for terminating the self-renewal process. Inhibition of caspase 3 results in elevated Pax7 protein and SC self-renewal, whereas caspase activation leads to Pax7 cleavage and initiation of the myogenic differentiation program. Moreover, in vivo inhibition of caspase 3 activity leads to a profound disruption in skeletal muscle regeneration with an accumulation of SCs within the niche. We have also noted that casein kinase 2 (CK2)-directed phosphorylation of Pax7 attenuates caspase-directed cleavage. Together, these results demonstrate that SC fate is dependent on opposing posttranslational modifications of the Pax7 protein. PMID:26372956

  10. Nitric oxide sustains long-term skeletal muscle regeneration by regulating fate of satellite cells via signaling pathways requiring Vangl2 and cyclic GMP.

    PubMed

    Buono, Roberta; Vantaggiato, Chiara; Pisa, Viviana; Azzoni, Emanuele; Bassi, Maria Teresa; Brunelli, Silvia; Sciorati, Clara; Clementi, Emilio

    2012-02-01

    Satellite cells are myogenic precursors that proliferate, activate, and differentiate on muscle injury to sustain the regenerative capacity of adult skeletal muscle; in this process, they self-renew through the return to quiescence of the cycling progeny. This mechanism, while efficient in physiological conditions does not prevent exhaustion of satellite cells in pathologies such as muscular dystrophy where numerous rounds of damage occur. Here, we describe a key role of nitric oxide, an important signaling molecule in adult skeletal muscle, on satellite cells maintenance, studied ex vivo on isolated myofibers and in vivo using the α-sarcoglycan null mouse model of dystrophy and a cardiotoxin-induced model of repetitive damage. Nitric oxide stimulated satellite cells proliferation in a pathway dependent on cGMP generation. Furthermore, it increased the number of Pax7(+)/Myf5(-) cells in a cGMP-independent pathway requiring enhanced expression of Vangl2, a member of the planar cell polarity pathway involved in the Wnt noncanonical pathway. The enhanced self-renewal ability of satellite cells induced by nitric oxide is sufficient to delay the reduction of the satellite cell pool during repetitive acute and chronic damages, favoring muscle regeneration; in the α-sarcoglycan null dystrophic mouse, it also slowed disease progression persistently. These results identify nitric oxide as a key messenger in satellite cells maintenance, expand the significance of the Vangl2-dependent Wnt noncanonical pathway in myogenesis, and indicate novel strategies to optimize nitric oxide-based therapies for muscular dystrophy. PMID:22084027

  11. Detection of satellite remnants in the Galactic Halo with Gaia - II. A modified great circle cell method

    NASA Astrophysics Data System (ADS)

    Mateu, C.; Bruzual, G.; Aguilar, L.; Brown, A. G. A.; Valenzuela, O.; Carigi, L.; Velázquez, H.; Hernández, F.

    2011-07-01

    We propose an extension of the great circle cell count streamer finding method of Johnston et al. that can be applied to the future Gaia data base. The original method looks for streamers along great circles in the sky, our extension adds the kinematical restriction that velocity vectors should also be constrained to lie along these great circles, as seen by a Galactocentric observer. We show how to use these combined criteria starting from heliocentric observables. We test it by using the mock Gaia catalogue of Brown et al., which includes a realistic Galactic background and observational errors, but with the addition of detailed star formation histories for the simulated satellites. We investigate its success rate as a function of initial satellite luminosity, star formation history and orbit. We find that the inclusion of the kinematical restriction vastly enhances the contrast between a streamer and the background, even in the presence of observational errors, provided we use only data with good astrometric quality (fractional errors of 30 per cent or better). The global nature of the method diminishes the erasing effect of phase mixing and permits the recovery of merger events of reasonable dynamical age. Satellites with a star formation history different to that of the Galactic background are also better isolated. We find that satellites in the range of 108-109 L⊙ can be recovered even for events as old as ˜10 Gyr. Even satellites with 4-5 × 107 L⊙ can be recovered for certain combinations of dynamical ages and orbits.

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

    PubMed

    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. PMID:25878030

  13. Muscle fiber characteristics, satellite cells and soccer performance in young athletes.

    PubMed

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

    2014-09-01

    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. Key PointsFifteen years old soccer players have higher IIA percentage distribution than the younger players by approximately 18%.The age and the training status play a crucial role in muscle fibers co-expression.Specific training in young athletes seems to alter significantly the muscular metabolic profile. PMID:25177173

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

    PubMed Central

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

    2014-01-01

    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. Key Points Fifteen years old soccer players have higher IIA percentage distribution than the younger players by approximately 18%. The age and the training status play a crucial role in muscle fibers co-expression. Specific training in young athletes seems to alter significantly the muscular metabolic profile. PMID:25177173

  15. Botulinum neurotoxin type A modulates vesicular release of glutamate from satellite glial cells

    PubMed Central

    da Silva, Larissa Bittencourt; Poulsen, Jeppe Nørgaard; Arendt-Nielsen, Lars; Gazerani, Parisa

    2015-01-01

    This study investigated the presence of cell membrane docking proteins synaptosomal-associated protein, 25 and 23 kD (SNAP-25 and SNAP-23) in satellite glial cells (SGCs) of rat trigeminal ganglion; whether cultured SGCs would release glutamate in a time- and calcium-dependent manner following calcium-ionophore ionomycin stimulation; and if botulinum neurotoxin type A (BoNTA), in a dose-dependent manner, could block or decrease vesicular release of glutamate. SGCs were isolated from the trigeminal ganglia (TG) of adult Wistar rats and cultured for 7 days. The presence of SNAPs in TG sections and isolated SGCs were investigated using immunohistochemistry and immunocytochemistry, respectively. SGCs were stimulated with ionomycin (5 μM for 4, 8, 12 and 30 min.) to release glutamate. SGCs were then pre-incubated with BoNTA (24 hrs with 0.1, 1, 10 and 100 pM) to investigate if BoNTA could potentially block ionomycin-stimulated glutamate release. Glutamate concentrations were measured by ELISA. SNAP-25 and SNAP-23 were present in SGCs in TG sections and in cultured SGCs. Ionomycin significantly increased glutamate release from cultured SGCs 30 min. following the treatment (P < 0.001). BoNTA (100 pM) significantly decreased glutamate release (P < 0.01). Results from this study demonstrated that SGCs, when stimulated with ionomycin, released glutamate that was inhibited by BoNTA, possibly through cleavage of SNAP-25 and/or SNAP-23. These novel findings demonstrate the existence of vesicular glutamate release from SGCs, which could potentially play a role in the trigeminal sensory transmission. In addition, interaction of BoNTA with non-neuronal cells at the level of TG suggests a potential analgesic mechanism of action of BoNTA. PMID:25754332

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

    PubMed

    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. PMID:25447026

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

    PubMed Central

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

    2014-01-01

    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 CDK inhibitors (CDKI) 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 FGF-2 is found in association with p21 and p16 promoters, and moreover, only in the old cells. Importantly, in the old satellite cells FGF-2/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 asp15INK4B and p27KIP1, 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. PMID:25447026

  18. Decreasing trend of groundwater in Turkey

    NASA Astrophysics Data System (ADS)

    Sarachi, S.; Moghim, S.; Famiglietti, J. S.

    2010-12-01

    In these days the increasing demand for water has created problems for availability of its resources. Some recent issues like population growth, global warming and inefficient methods of water consumption, generated the need to find sources of water other than surface water such as ground water. Excess using of groundwater in most parts of the world causes depletion of ground water in those areas. Scientists are trying to find efficient means to quantify these trends. GRACE (Gravity Recovery and Climate Experiment) including two satellites launched in March 2002, is making measurements of the Earth's gravity field which is used to display the change of storage of the water on the Earth. GRACE makes it possible to find the trend of the change of storage all over the world.It can show specific areas in the world that have dramatic decreasing trend of water storage. One of these regions that have been considered in this study is Turkey in western Asia, as one of the countries deeply affected by global warming. Turkey is identified as one of the first places where desertification will start in Europe, according to estimates by the UN Environment Program (UNEP). Turkey has 25 underground water tables and they had a decrease in level of 27 meters in the past 25 years (Turkey water report 2009). In this paper the change of the ground water is evaluated by applying the GRACE storage anomalies and the mass conservation equation that concludes the reduction trend in groundwater. The results clarify that decreasing trend of groundwater is more noticeable during recent years, particularly since 2006. Our results show that in recent years the average decrease in ground water level is 2.5 cm per year and the maximum decrease occurred in May 2007 with the value of about 7.9 cm. KEY WORDS: water resources; Ground water; Turkey; GRACE

  19. Myocarditis associated with reovirus in turkey poults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Myocarditis associated with reovirus was diagnosed in 17 day-old male turkey poults based on virus isolation, reverse transcript – polymerase chain reaction (RT-PCR), demonstration of reovirus antigen in the cytoplasm of mononuclear inflammatory cells and myocytes in the heart by immunohistochemistr...

  20. Informatics in Turkey

    NASA Technical Reports Server (NTRS)

    Cakir, Serhat

    1994-01-01

    In the last twenty years the rapid change in the informatics sector has had economic and social impact on private and government activities. The Supreme Council for Science and Technology of Turkey assigned highest priority to the informatics in its meeting in February 1993. With this advice TUBITAK (The Scientific and Technical Research Council of Turkey) intends to give a strong impulse to development of a research policy in this field.

  1. Repetitive centromeric satellite RNA is essential for kinetochore formation and cell division

    PubMed Central

    Rošić, Silvana; Köhler, Florian

    2014-01-01

    Chromosome segregation requires centromeres on every sister chromatid to correctly form and attach the microtubule spindle during cell division. Even though centromeres are essential for genome stability, the underlying centromeric DNA is highly variable in sequence and evolves quickly. Epigenetic mechanisms are therefore thought to regulate centromeres. Here, we show that the 359-bp repeat satellite III (SAT III), which spans megabases on the X chromosome of Drosophila melanogaster, produces a long noncoding RNA that localizes to centromeric regions of all major chromosomes. Depletion of SAT III RNA causes mitotic defects, not only of the sex chromosome but also in trans of all autosomes. We furthermore find that SAT III RNA binds to the kinetochore component CENP-C, and is required for correct localization of the centromere-defining proteins CENP-A and CENP-C, as well as outer kinetochore proteins. In conclusion, our data reveal that SAT III RNA is an integral part of centromere identity, adding RNA to the complex epigenetic mark at centromeres in flies. PMID:25365994

  2. Neuronal soma-satellite glial cell interactions in sensory ganglia and the participation of purinergic receptors

    PubMed Central

    Gu, Yanping; Chen, Yong; Zhang, Xiaofei; Li, GuangWen; Wang, Cong Ying; Huang, Li-Yen Mae

    2011-01-01

    It has been known for some time that the somata of neurons in sensory ganglia respond to electrical or chemical stimulation and release transmitters in a Ca2+-dependent manner. The function of the somatic release has not been well delineated. A unique characteristic of the ganglia is that each neuronal soma is tightly enwrapped by satellite glial cells (SGCs). The somatic membrane of a sensory neuron rarely makes synaptic contact with another neuron. As a result, the influence of somatic release on the activity of adjacent neurons is likely to be indirect and/or slow. Recent studies of neuron-SGC interactions have demonstrated that ATP released from the somata of dorsal root ganglion neurons activates SGCs. They in turn exert complex excitatory and inhibitory modulation of neuronal activity. Thus, SGCs are actively involved in the processing of afferent information. In this review, we summarize our understanding of bidirectional communication between neuronal somata and SGCs in sensory ganglia and its possible role in afferent signaling under normal and injurious conditions. The participation of purinergic receptors is emphasized because of their dominant roles in the communication. PMID:20604979

  3. Acute tissue injury activates satellite cells and promotes sarcoma formation via the HGF/c-MET signaling pathway

    PubMed Central

    Van Mater, David; Añó, Leonor; Blum, Jordan M.; Webster, Micah T.; Huang, WeiQiao; Williams, Nerissa; Ma, Yan; Cardona, Diana M.; Fan, Chen-Min; Kirsch, David G.

    2015-01-01

    Some patients with soft tissue sarcoma (STS) report a history of injury at the site of their tumor. While this phenomenon is widely reported, there are relatively few experimental systems that have directly assessed the role of injury in sarcoma formation. We recently described a mouse model of STS whereby p53 is deleted and oncogenic Kras is activated in muscle satellite cells via a Pax7CreER driver following intraperitoneal injection with tamoxifen. Here, we report that after systemic injection of tamoxifen, the vast majority of Pax7-expressing cells remain quiescent despite mutation of p53 and Kras. The fate of these muscle progenitors is dramatically altered by tissue injury, which leads to faster kinetics of sarcoma formation. In adult muscle, quiescent satellite cells will transition into an active state in response to hepatocyte growth factor (HGF). We show that modulating satellite cell quiescence via intramuscular (IM) injection of HGF increases the penetrance of sarcoma formation at the site of injection, which is dependent on its cognate receptor c-MET. Unexpectedly, the tumor promoting effect of tissue injury also requires c-Met. These results reveal a mechanism by which HGF/c-MET signaling promotes tumor formation after tissue injury in a mouse model of primary STS, and they may explain why some patients develop a STS at the site of injury. PMID:25503558

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

    PubMed Central

    Yin, Hang; Pasut, Alessandra; Soleimani, Vahab D.; Bentzinger, C. Florian; Antoun, Ghadi; Thorn, Stephanie; Seale, Patrick; Fernando, Pasan; van IJcken, Wilfred; Grosveld, Frank; Dekemp, Robert A.; Boushel, Robert; Harper, Mary-Ellen; Rudnicki, Michael A.

    2013-01-01

    SUMMARY Brown adipose tissue (BAT) is an energy-dispensing thermogenic tissue that plays an important role in balancing energy metabolism. Lineage-tracing experiments indicate that brown adipocytes are derived from myogenic progenitors during embryonic development. However, adult skeletal muscle stem cells (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 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 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. PMID:23395168

  5. Fumonisin toxicity in turkey poults.

    PubMed

    Weibking, T S; Ledoux, D R; Brown, T P; Rottinghaus, G E

    1993-01-01

    The effects of dietary fumonisin B1 were evaluated in young turkey poults. The experimental design consisted of 3 treatments, with 24 female turkey poults allotted randomly per treatment. Day-old poults were fed diets containing 0 mg (feed control), 100 mg, and 200 mg fumonisin B1/kg feed for 21 days. Body weight gains and efficiency of feed conversion decreased linearly with increasing dietary fumonisin. Liver, kidney, and pancreas weights increased linearly with increasing dietary fumonisin, and spleen and heart weights decreased. Serum aspartate aminotransferase levels increased with increasing dietary fumonisin, and serum cholesterol; alkaline phosphatase, mean cell volume, and mean cell hemoglobin all decreased. Biliary hyperplasia, hypertrophy of Kupffer's cells, thymic cortical atrophy, and moderate widening of the proliferating and degenerating hypertrophied zones of tibial physes were present in poults fed diets containing fumonisin B1. Results indicate that fumonisin B1, from Fusarium moniliforme culture material, is toxic in young poults, and the poult appears to be more sensitive to fumonisin than the broiler chick. PMID:8466985

  6. S1P lyase in skeletal muscle regeneration and satellite cell activation: Exposing the hidden lyase☆

    PubMed Central

    Saba, Julie D.; de la Garza-Rodea, Anabel S.

    2013-01-01

    Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid whose actions are essential for many physiological processes including angiogenesis, lymphocyte trafficking and development. In addition, S1P serves asamuscle trophic factor that enables efficient muscle regeneration. This is due in part to S1P's ability to activate quiescent muscle stem cells called satellite cells (SCs) that are needed for muscle repair. However, the molecular mechanism by which S1P activates SCs has not been well understood. Further, strategies for harnessing S1P signaling to recruit SCs for therapeutic benefit have been lacking. S1P is irreversibly catabolized by S1P lyase (SPL), a highly conserved enzyme that catalyzes the cleavage of S1P at carbon bond C2–3, resulting in formation of hexadecenal and ethanolamine-phosphate. SPL enhances apoptosis through substrate- and product-dependent events, thereby regulating cellular responses to chemotherapy, radiation and ischemia. SPL is undetectable in resting murine skeletal muscle. However, we recently found that SPL is dynamically upregulated in skeletal muscle after injury. SPL upregulation occurred in the context of a tightly orchestrated genetic program that resulted in a transient S1P signal in response to muscle injury. S1P activated quiescent SCs via a sphingosine-1-phosphate receptor 2 (S1P2)/signal transducer and activator of transcription 3 (STAT3)-dependent pathway, thereby facilitating skeletal muscle regeneration. Mdx mice, which serve as a model for muscular dystrophy (MD), exhibited skeletal muscle SPL upregulation and S1P deficiency. Pharmacological SPL inhibition raised skeletal muscle S1P levels, enhanced SC recruitment and improved mdx skeletal muscle regeneration. These findings reveal how S1P can activate SCs and indicate that SPL suppression may provide a therapeutic strategy for myopathies. This article is part of a Special Issue entitled Advances in Lysophospholipid Research. PMID:22750505

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

    NASA Technical Reports Server (NTRS)

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

    1994-01-01

    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

  8. 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

    NASA Technical Reports Server (NTRS)

    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.

  9. microRNA-1 and microRNA-206 regulate skeletal muscle satellite cell proliferation and differentiation by repressing Pax7

    PubMed Central

    Chen, Jian-Fu; Tao, Yazhong; Li, Juan; Deng, Zhongliang; Yan, Zhen; Xiao, Xiao

    2010-01-01

    Skeletal muscle satellite cells are adult stem cells responsible for postnatal skeletal muscle growth and regeneration. Paired-box transcription factor Pax7 plays a central role in satellite cell survival, self-renewal, and proliferation. However, how Pax7 is regulated during the transition from proliferating satellite cells to differentiating myogenic progenitor cells is largely unknown. In this study, we find that miR-1 and miR-206 are sharply up-regulated during satellite cell differentiation and down-regulated after muscle injury. We show that miR-1 and miR-206 facilitate satellite cell differentiation by restricting their proliferative potential. We identify Pax7 as one of the direct regulatory targets of miR-1 and miR-206. Inhibition of miR-1 and miR-206 substantially enhances satellite cell proliferation and increases Pax7 protein level in vivo. Conversely, sustained Pax7 expression as a result of the loss of miR-1 and miR-206 repression elements at its 3′ untranslated region significantly inhibits myoblast differentiation. Therefore, our experiments suggest that microRNAs participate in a regulatory circuit that allows rapid gene program transitions from proliferation to differentiation. PMID:20819939

  10. High Energy Instrumentation Efforts in Turkey

    SciTech Connect

    Kalemci, Emrah

    2011-09-21

    This work summarizes the efforts in Turkey to build a laboratory capable of building and testing high energy astrophysics detectors that work in space. The EC FP6 ASTRONS project contributed strongly to these efforts, and as a result a fully operational laboratory at Sabanci University have been developed. In this laboratory we test and develop Si and CdZnTe based room temperature semiconductor strip detectors and develop detector and electronics system to be used as a payload on potential small Turkish satellites.

  11. Satellite cell senescence underlies myopathy in a mouse model of limb-girdle muscular dystrophy 2H.

    PubMed

    Kudryashova, Elena; Kramerova, Irina; Spencer, Melissa J

    2012-05-01

    Mutations in the E3 ubiquitin ligase tripartite motif-containing 32 (TRIM32) are responsible for the disease limb-girdle muscular dystrophy 2H (LGMD2H). Previously, we generated Trim32 knockout mice (Trim32-/- mice) and showed that they display a myopathic phenotype accompanied by neurogenic features. Here, we used these mice to investigate the muscle-specific defects arising from the absence of TRIM32, which underlie the myopathic phenotype. Using 2 models of induced atrophy, we showed that TRIM32 is dispensable for muscle atrophy. Conversely, TRIM32 was necessary for muscle regrowth after atrophy. Furthermore, TRIM32-deficient primary myoblasts underwent premature senescence and impaired myogenesis due to accumulation of PIAS4, an E3 SUMO ligase and TRIM32 substrate that was previously shown to be associated with senescence. Premature senescence of myoblasts was also observed in vivo in an atrophy/regrowth model. Trim32-/- muscles had substantially fewer activated satellite cells, increased PIAS4 levels, and growth failure compared with wild-type muscles. Moreover, Trim32-/- muscles exhibited features of premature sarcopenia, such as selective type II fast fiber atrophy. These results imply that premature senescence of muscle satellite cells is an underlying pathogenic feature of LGMD2H and reveal what we believe to be a new mechanism of muscular dystrophy associated with reductions in available satellite cells and premature sarcopenia. PMID:22505452

  12. Impedances of Li/SO2 cells retrieved from the Long Duration Exposure Facility (LDEF satellite) and comparison with cells stored terrestrially

    NASA Astrophysics Data System (ADS)

    Reid, Margaret A.

    1991-11-01

    Impedances were measured on several Li/SO2 cells retrieved from the Long Duration Exposure Facility (LDEF) satellite. These cells were used to power instruments and recorders and had all been partially or fully discharged. Impedances were also measured on several cells that were stored in cold storage since manufacture. Unfortunately, none of the cells stored terrestrially had undergone any discharge, whereas all of the cells on the satellite were at least partially discharged early in the mission and then remained on orbit for about 5 years further. It has been observed by others that storage of an Li/SO2 cell after partial discharge, increases the resistance and thickness of the passive film on the Li electrode, as indicated by an increase in the time for recovery of voltage when a load is applied (voltage lag), or in some cases by an inability of a cell to sustain a normal current after such storage. Since the cells stored terrestrially were not discharged in the same manner as the LDEF cells, a direct comparison cannot be made. Thus, the effects of the space environment cannot be separated from the effects of storage after partial discharge. It is believed that the increases in impedance in the LDEF cells are largely due to the storage upon partial discharge rather than the effects of the space environment.

  13. The different fate of satellite cells on conductive composite electrospun nanofibers with graphene and graphene oxide nanosheets.

    PubMed

    Mahmoudifard, Matin; Soleimani, Masoud; Hatamie, Shadie; Zamanlui, Soheila; Ranjbarvan, Parviz; Vossoughi, Manouchehr; Hosseinzadeh, Simzar

    2016-04-01

    Electrospinning of composite polymer solutions provides fantastic potential to prepare novel nanofibers for use in a variety of applications. The addition of graphene (G) and graphene oxide (GO) nanosheets to bioactive polymers was found to enhance their conductivity and biocompatibility. Composite conductive nanofibers of polyaniline (PANI) and polyacrylonitrile (PAN) with G and GO nanosheets were prepared by an electrospinning process. The fabricated membranes were investigated by physical and chemical examinations including scanning electron microscopy (SEM), Raman spectroscopy, x-ray diffraction (XRD) and tensile assay. The muscle satellite cells enriched by a pre-plating technique were cultured in the following and their proliferation and differentiation behavior studied by MTT, Real-Time PCR assays and 4', 6-diamidino-2-phenylindole (DAPI) staining. The cultured cells on composite nanofibrous PAN/PANI-CSA/G confirmed a higher proliferation and differentiation value compared to other groups including PAN/PANI-CSA/GO and PAN/PANI-CSA scaffolds. Furthermore, the higher stiffness of the former scaffold showed a lower cell spreading as a function of stem cell activation into more proliferative cells. It is supposed that the enhanced conductivity value in addition to relative higher stiffness of the PAN/PANI-CSA/G composite nanofibers plays a favorable role for proliferation and differentiation of satellite cells. PMID:26962722

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

    PubMed

    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. PMID:26393303

  15. Epidermal growth factor receptor is required for estradiol-stimulated bovine satellite cell proliferation.

    PubMed

    Reiter, B C; Kamanga-Sollo, E; Pampusch, M S; White, M E; Dayton, W R

    2014-07-01

    The objective of this study was to assess the role of the epidermal growth factor receptor (EGFR) in estradiol-17β (E2)-stimulated proliferation of cultured bovine satellite cells (BSCs). Treatment of BSC cultures with AG1478 (a specific inhibitor of EGFR tyrosine kinase activity) suppresses E2-stimulated BSC proliferation (P < 0.05). In addition, E2-stimulated proliferation is completely suppressed (P < 0.05) in BSCs in which EGFR expression is silenced by treatment with EGFR small interfering RNA (siRNA). These results indicate that EGFR is required for E2 to stimulate proliferation in BSC cultures. Both AG1478 treatment and EGFR silencing also suppress proliferation stimulated by LR3-IGF-1 (an IGF1 analogue that binds normally to the insulin-like growth factor receptor (IGFR)-1 but has little or no affinity for IGF binding proteins) in cultured BSCs (P < 0.05). Even though EGFR siRNA treatment has no effect on IGFR-1β mRNA expression in cultured BSCs, IGFR-1β protein level is substantially reduced in BSCs treated with EGFR siRNA. These data suggest that EGFR silencing results in post-transcriptional modifications that result in decreased IGFR-1β protein levels. Although it is clear that functional EGFR is necessary for E2-stimulated proliferation of BSCs, the role of EGFR is not clear. Transactivation of EGFR may directly stimulate proliferation, or EGFR may function to maintain the level of IGFR-1β which is necessary for E2-stimulated proliferation. It also is possible that the role of EGFR in E2-stimulated BSC proliferation may involve both of these mechanisms. PMID:24906928

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

    SciTech Connect

    Zhang, Feng; Deng, Bing; Wen, Jianghui; Chen, Kun; Liu, Wu; Ye, Shengqiang; Huang, Haijun; Jiang, Siwen; Xiong, Yuanzhu

    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.

  17. Transcriptional profiling identifies differentially expressed genes in developing turkey skeletal muscle

    PubMed Central

    2011-01-01

    Background Skeletal muscle growth and development from embryo to adult consists of a series of carefully regulated changes in gene expression. Understanding these developmental changes in agriculturally important species is essential to the production of high quality meat products. For example, consumer demand for lean, inexpensive meat products has driven the turkey industry to unprecedented production through intensive genetic selection. However, achievements of increased body weight and muscle mass have been countered by an increased incidence of myopathies and meat quality defects. In a previous study, we developed and validated a turkey skeletal muscle-specific microarray as a tool for functional genomics studies. The goals of the current study were to utilize this microarray to elucidate functional pathways of genes responsible for key events in turkey skeletal muscle development and to compare differences in gene expression between two genetic lines of turkeys. To achieve these goals, skeletal muscle samples were collected at three critical stages in muscle development: 18d embryo (hyperplasia), 1d post-hatch (shift from myoblast-mediated growth to satellite cell-modulated growth by hypertrophy), and 16wk (market age) from two genetic lines: a randombred control line (RBC2) maintained without selection pressure, and a line (F) selected from the RBC2 line for increased 16wk body weight. Array hybridizations were performed in two experiments: Experiment 1 directly compared the developmental stages within genetic line, while Experiment 2 directly compared the two lines within each developmental stage. Results A total of 3474 genes were differentially expressed (false discovery rate; FDR < 0.001) by overall effect of development, while 16 genes were differentially expressed (FDR < 0.10) by overall effect of genetic line. Ingenuity Pathways Analysis was used to group annotated genes into networks, functions, and canonical pathways. The expression of 28 genes

  18. Comparison of growth characteristics between skeletal muscle satellite cell lines from diploid and triploid olive flounder Paralichthys olivaceus

    PubMed Central

    Wu, Zhi-hao; Tan, Xungang; Jiao, Shuang; Zhang, Pei-jun

    2016-01-01

    Objectives. According to myosatellite cell lines (MSCs) established in vitro from diploid and triploid flounder, we compared the characters of growth and differentiation of their MSCs. The results would be useful for learning the muscle development mechanism in teleosts. Materials and Methods. The skeletal muscle cells from the diploid and triploid olive flounder Paralichthys olivaceus were isolated and cultured in vitro, respectively, and the cells were characterized at the morphology and molecular level; meanwhile, the performance of these cells’ proliferation and differentiation were analyzed. Results. Two new skeletal muscle cell lines (POMSCS(2n) and POMSCS(3n)) from diploid and triploid flounder have been respectively subcultured for 67 times and 66 times. The cultured cells were mostly spindle-like mononuclear cells. They have normal flounder diploid karyotype (2n=48t) and triploid karyotype (3n=72t), respectively. Muscle satellite cell gene marker (pax7b) and myogenic cell protein marker (Desmin) were all expressed in cells of two cell lines. Both of the cells could differentiate into the large polynucleated muscle fibre cells, and immunofluorescence reactions of myosin heavy chain (MyHC) were positive. There were more cells of POMSCS(3n) to differentiate into the muscle fibre cells than that of POMSCS(2n). However, POMSCS(2n) cells proliferated more rapidly than those of POMSCS(3n) (P < 0.05). The significant fluorescent signals were observed in both POMSCS(2n) and POMSCS(3n) cells after transfected with pEGFP-N3 reporter plasmid. Conclusions. The two cell lines have been established and characterized as MSCs. We suppose that it might be the differentiation capacity, rather than the proliferation activity of MSCs to play a key role in the better growth of triploid ones than diploid. Both cell lines will become the ideal tools to learn the mechanism of fish MSCs proliferation, differentiation and regeneration during muscle development in the future. PMID

  19. The Acute Satellite Cell Response and Skeletal Muscle Hypertrophy following Resistance Training

    PubMed Central

    Mitchell, Cameron J.; McKay, Bryon R.; Phillips, Stuart M.; Baker, Steven; Parise, Gianni

    2014-01-01

    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. PMID:25313863

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

    PubMed

    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. PMID:27086138

  1. Echinococcosis multilocularis in Turkey.

    PubMed

    Uysal, V; Paksoy, N

    1986-10-01

    We present 20 new cases of Echinococcosis multilocularis (EM) and have also reviewed all 137 previously reported cases from Turkey. The total number of cases is now 157 up until the end of 1983. Of 146 cases with information on their place of occurrence, 133 (91%) were from eastern and central parts of Turkey or the region of the Black Sea where the cold climate is predominant. This area should be considered as part of the geographic distribution of Echinococcus multilocularis which extends from the Caucasian Republics (Azerbaijan and Georgian S.S.R.) to Siberia in the Soviet Union. EM is more frequent among the people involved in raising livestock in the rural areas of Turkey. Most of the cases (76%) were between the ages of 30 and 50; 53% were males. One hundred and thirty nine cases (92%) were liver infections, and most of the cases (60%) were clinically diagnosed as liver tumour. PMID:3795325

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

    PubMed Central

    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

  3. Chronological changes in acid phosphatase activity within neurons and perineuronal satellite cells of the inferior vagal ganglion of the cat induced by vagotomy.

    PubMed Central

    Glover, R A

    1982-01-01

    The hexazonium pararosaniline method was employed to describe the distribution of acid phosphatase activity, chronologically, within neurons and their investing satellite cells of the inferior vagal ganglion of the cat after vagotomy. In control ganglia, acid phosphatase activity was invariably confined to the cytoplasm of neurons and satellite cells. Reaction product was visible as distinct granules within neuronal perikarya. The cytoplasm of perineuronal satellite cells also contained reaction product but, in most instances, activity was weak and granules were difficult to distinguish. No reaction product was observed in myelin or axonal processes; nuclear staining was absent. Acid phosphatase activity was increased in ganglionic neurons as early as 24 hours after vagotomy. Increased activity in perineuronal satellite cells was not evident until 3 days post-operatively. By 15 days, activity was ubiquitously increased in the cytoplasm of both neurons and satellite cells. Evidence suggesting neuronophagia was also apparent. Between 30 and 60 days post-operatively acid phosphatase activity gradually decreased in both neurons and satellite cells until a picture comparable with that seen in control tissue sections was visible. The functional significance of these changes in acid phosphatase activity within an altered metabolic environment induced by vagotomy is discussed. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 PMID:7076551

  4. Small Cell Carcinomas of the Bladder Highly Express Somatostatin Receptor Type 2A: Impact on Prognosis and Treatment-A Multicenter Study of Urooncology Society, Turkey.

    PubMed

    Neşe, Nalan; Kumbaraci, Banu S; Baydar, Dilek E; Kiliçaslan, Işin; Sari, Ayşegül A; Şen, Sait; Gönül, Ipek I; Kankaya, Duygu; Özlük, Yasemin; Ermete, Murat; Özağari, Ayşim; Bal, Nebil; Kiremitçi, Saba; Yildiz, Kürşat; Tuna, Burçin; Şen, Nilay; Yörükoğlu, Kutsal

    2016-04-01

    Small cell carcinoma (SmCC) is a rare and aggressive neuroendocrine carcinoma of the bladder. Neuroendocrine carcinomas expressing somatostatin receptors (SSTR) in other viscera such as lung, pancreas, and gastrointestinal system respond to therapy with somatostatin analogs. In the present study, expressions of SSTRs 1 to 5 including type 2A are investigated by immunohistochemistry (IHC) and their relationship with clinicopathologic factors was evaluated. Hundred primary bladder SmCC cases were collected from 12 centers in Turkey. Forty-three cases were pure SmCC. Other cases had mostly papillary urothelial carcinoma as a second component. The percentage of the SmCC component ranged from 5% to 100%. SSTR-2A expression was membranous, whereas the other receptors showed cytoplasmic staining. The percentages of positive cases for SSTR-1, SSTR-2A, SSTR-3, SSTR-4, and SSTR-5 were 4% (3/75), 61.4% (54/88), 2.4% (2/84), 24.4% (20/82), and 6.25% (5/80), respectively. The percentage of SmCC component was positively correlated with the percentage of SSTR-2A expression (P=0.003) while negatively correlated with patient age (P=0.032). SSTR-2A expression was correlated with survival as a bad prognostic factor (P=0.018). SSTR-1, SSTR-3, SSTR-4, and SSTR-5 expressions did not show any statistical significance with any parameter. In conclusion, although the limited number of cases with adequate term follow-up, SSTR-2A expression could be a prognostic factor and somatostatin analogs therapeutic candidate for SmCCs of the bladder as these tumors show high percentage of SSTR-2A expression. PMID:25906124

  5. Network Analysis for the Identification of Differentially Expressed Hub Genes Using Myogenin Knock-down Muscle Satellite Cells

    PubMed Central

    Jan, Arif Tasleem; Ahmad, Sarafraz; Cho, Kyung-Hyun; Kim, Jihoe; Choi, Inho

    2015-01-01

    Muscle, a multinucleate syncytium formed by the fusion of mononuclear myoblasts, arises from quiescent progenitors (satellite cells) via activation of muscle-specific transcription factors (MyoD, Myf5, myogenin: MYOG, and MRF4). Subsequent to a decline in Pax7, induction in the expression of MYOG is a hallmark of myoblasts that have entered the differentiation phase following cell cycle withdrawal. It is evident that MYOG function cannot be compensated by any other myogenic regulatory factors (MRFs). Despite a plethora of information available regarding MYOG, the mechanism by which MYOG regulates muscle cell differentiation has not yet been identified. Using an RNA-Seq approach, analysis of MYOG knock-down muscle satellite cells (MSCs) have shown that genes associated with cell cycle and division, DNA replication, and phosphate metabolism are differentially expressed. By constructing an interaction network of differentially expressed genes (DEGs) using GeneMANIA, cadherin-associated protein (CTNNA2) was identified as the main hub gene in the network with highest node degree. Four functional clusters (modules or communities) were identified in the network and the functional enrichment analysis revealed that genes included in these clusters significantly contribute to skeletal muscle development. To confirm this finding, in vitro studies revealed increased expression of CTNNA2 in MSCs on day 12 compared to day 10. Expression of CTNNA2 was decreased in MYOG knock-down cells. However, knocking down CTNNA2, which leads to increased expression of extracellular matrix (ECM) genes (type I collagen α1 and type I collagen α2) along with myostatin (MSTN), was not found significantly affecting the expression of MYOG in C2C12 cells. We therefore propose that MYOG exerts its regulatory effects by acting upstream of CTNNA2, which in turn regulates the differentiation of C2C12 cells via interaction with ECM genes. Taken together, these findings highlight a new mechanism by which

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

    PubMed Central

    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 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. PMID:22916712

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

    PubMed Central

    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. PMID:26709824

  8. Influence of static magnetic fields combined with human insulin-like growth factor 1 on human satellite cell cultures.

    PubMed

    Birk, Richard; Sommer, J Ulrich; Haas, Dominik; Faber, Anne; Aderhold, Christoph; Schultz, Johannes D; Hoermann, Karl; Stern-Straeter, Jens

    2014-01-01

    Tissue engineering represents a promising research field, targeting the creation of new functional muscle tissue in vitro. The aim of the present study was to show the influence of static magnetic fields (SMF) and insulin-like growth factor-1 (IGF1), as enhancing stimuli on human satellite cell cultures, which are preferred sources of stem cells in engineering skeletal muscle tissue. To detect effects on myogenic maturation and proliferation, AlamarBlue® proliferation, assay and semi-quantitative reverse transcription-polymerase chain reaction of following markers was performed: desmin (DES), myogenic factor-5 (MYF5), myogenic differentiation antigen-1 (MYOD1), myogenin (MYOG), myosin heavy chain (MYH) and α1 actin (ACTA1). As a distinct marker of differentiation, immunohistochemical staining and fusion index determination was performed on satellite cell cultures stimulated with IGF1 and IGF1-plus-SMF with an intensity of 80 mT. Proliferation was increased by additional SMF application to IGF1-stimulated cell cultures on the first day of myogenesis. Relative gene expression of measured markers was increased by IGF1 application in the first days of myogenesis except for ACTA1. Additional SMF application enhanced this effect. Nevertheless we were unable to demonstrate the formation of contractile muscle tissue. Immunhistochemical staining verified muscle origin and all markers were displayed. PMID:25189891

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

    PubMed Central

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

    2016-01-01

    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. PMID:26871970

  10. Satellite Communication.

    ERIC Educational Resources Information Center

    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…

  11. Potential of adipose-derived mesenchymal stem cells and skeletal muscle-derived satellite cells for somatic cell nuclear transfer mediated transgenesis in Arbas Cashmere goats.

    PubMed

    Ren, Yu; Wu, Haiqing; Ma, Yuzhen; Yuan, Jianlong; Liang, Hao; Liu, Dongjun

    2014-01-01

    Somatic cell nuclear transfer is used to generate genetic models for research and new, genetically modified livestock varieties. Goat fetal fibroblast cells (gFFCs) are the predominant nuclear donors in Cashmere goat transgenic cloning, but have disadvantages. We evaluated the potential of goat adipose-derived mesenchymal stem cells (gADSCs) and goat skeletal muscle-derived satellite cells (gMDSCs) for somatic cell nuclear transfer, evaluating their proliferation, pluripotency, transfection efficiency and capacity to support full term development of embryos after additive gene transfer or homologous recombination. gADSCs and gMDSCs were isolated by enzyme digestion and differentiated into neurocytes, myotube cells and insulin-producing cells. Neuron-specific enolase, fast muscle myosin and insulin expression were determined by immunohistochemistry. Following somatic cell nuclear transfer with donor cells derived from gADSCs, gMDSCs and gFFCs, transfection and cloning efficiencies were compared. Red fluorescent protein levels were determined by quantitative PCR and western blotting. 5-Methylcytosine, H4K5, H4K12 and H3K18 were determined immunohistochemically. gADSCs and gMDSCs were maintained in culture for up to 65 passages, whereas gFFCs could be passaged barely more than 15 times. gADSCs and gMDSCs had higher fluorescent colony forming efficiency and greater convergence (20%) and cleavage (10%) rates than gFFCs, and exhibited differing H4K5 histone modification patterns after somatic cell nuclear transfer and in vitro cultivation. After transfection with a pDsRed2-1 expression plasmid, the integrated exogenous genes did not influence the pluripotency of gADSCs-pDsRed2-1 or gMDSCs-pDsRed2-1. DsRed2 mRNA expression by cloned embryos derived from gADSCs-pDsRed2-1 or gMDSCs-pDsRed2-1 was more than twice that of gFFCs-pDsRed2-1 embryos (P<0.01). Pregnancy rates of gADSCs-pDsRed2-1 and gMDSCs-pDsRed2-1 recipients were higher than those of gFFCs-pDsRed2-1 recipients (P

  12. Potential of Adipose-Derived Mesenchymal Stem Cells and Skeletal Muscle-Derived Satellite Cells for Somatic Cell Nuclear Transfer Mediated Transgenesis in Arbas Cashmere Goats

    PubMed Central

    Yuan, Jianlong; Liang, Hao; Liu, Dongjun

    2014-01-01

    Somatic cell nuclear transfer is used to generate genetic models for research and new, genetically modified livestock varieties. Goat fetal fibroblast cells (gFFCs) are the predominant nuclear donors in Cashmere goat transgenic cloning, but have disadvantages. We evaluated the potential of goat adipose-derived mesenchymal stem cells (gADSCs) and goat skeletal muscle-derived satellite cells (gMDSCs) for somatic cell nuclear transfer, evaluating their proliferation, pluripotency, transfection efficiency and capacity to support full term development of embryos after additive gene transfer or homologous recombination. gADSCs and gMDSCs were isolated by enzyme digestion and differentiated into neurocytes, myotube cells and insulin-producing cells. Neuron-specific enolase, fast muscle myosin and insulin expression were determined by immunohistochemistry. Following somatic cell nuclear transfer with donor cells derived from gADSCs, gMDSCs and gFFCs, transfection and cloning efficiencies were compared. Red fluorescent protein levels were determined by quantitative PCR and western blotting. 5-Methylcytosine, H4K5, H4K12 and H3K18 were determined immunohistochemically. gADSCs and gMDSCs were maintained in culture for up to 65 passages, whereas gFFCs could be passaged barely more than 15 times. gADSCs and gMDSCs had higher fluorescent colony forming efficiency and greater convergence (20%) and cleavage (10%) rates than gFFCs, and exhibited differing H4K5 histone modification patterns after somatic cell nuclear transfer and in vitro cultivation. After transfection with a pDsRed2-1 expression plasmid, the integrated exogenous genes did not influence the pluripotency of gADSCs–pDsRed2-1 or gMDSCs–pDsRed2-1. DsRed2 mRNA expression by cloned embryos derived from gADSCs–pDsRed2-1 or gMDSCs–pDsRed2-1 was more than twice that of gFFCs–pDsRed2-1 embryos (P<0.01). Pregnancy rates of gADSCs–pDsRed2-1 and gMDSCs–pDsRed2-1 recipients were higher than those of gFFCs–pDsRed2

  13. Significant role of μ-calpain (CANP1) in proliferation/survival of bovine skeletal muscle satellite cells.

    PubMed

    Van Ba, Hoa; Inho, Hwang

    2013-12-01

    Calpains are a family of Ca(2+)-dependent intracellular cysteine proteases, including the ubiquitously expressed μ-calpain (CANP1) and m-calpain (CANP2). The CANP1 has been found to play a central role in postmortem proteolysis and meat tenderization. However, the physiological roles of CANP1 in cattle skeletal satellite cells remain unclear. In this study, three small interference RNA sequences (siRNAs) targeting CANP1 gene were designed and ligated into pSilencer plasmid vector to construct shRNA expression constructs. Suppression of CANP1 in satellite cells was evaluated using these shRNA expressing constructs. Our results revealed that all three siRNAs could downregulate the expression of CANP1. Suppression of CANP1 significantly reduced cell viability in cell proliferation when compared with control cells. We found a crosstalk between CANP1 and caspase systems, particularly suppression of CANP1 resulted in an increase in the expressions of apoptotic caspases such as caspase-3, caspase-6, caspase-7, caspase-8, and caspase-9, as well as heat-shock protein (HSP) systems. Additionally, suppression of CANP1 led to the upregulation of other apoptosis and DNA damage-regulating genes whilst at the same time downregulating proliferation, migration, and differentiation-regulating genes. The results of our findings report for the first time that suppression of CANP1 resulted in the activation of caspase and HSP systems which might in turn regulate apoptosis through the caspase-dependent cell death pathway. This clearly demonstrates the key roles of CANP1 in regulation of cell proliferation and survival. PMID:23943438

  14. The "Turkey Buzzard" glider

    NASA Technical Reports Server (NTRS)

    Miller, Roy G; Brown, D T

    1923-01-01

    The "Turkey Buzzard" is a semi-internally braced monoplane (Fig. 1). The wing is placed above the fuselage for two important aerodynamical reasons: first, because this position minimizes the mutual interference between the wing and the fuselage, and, second, useful lifting surface is utilized with the wing passing over the fuselage instead of through it.

  15. Country Profiles, Turkey.

    ERIC Educational Resources Information Center

    Anderson, Lewis S.

    A profile of Turkey is sketched in this paper. Emphasis is placed on the nature, scope, and accomplishments of population activities in the country. Topics and sub-topics include: location and description of the country; population (size, growth patterns, age structure, urban/rural distribution, ethnic and religious composition, migration,…

  16. Special Education in Turkey

    ERIC Educational Resources Information Center

    Melekoglu, Macid A.; Cakiroglu, Orhan; Malmgren, Kimber W.

    2009-01-01

    Special education has been gaining intense attention from governments and educators throughout the world. As a developing country, and official candidate for the European Union, Turkey has been working on issues related to special education provision and inclusive education to improve the quality of services for citizens with disabilities. This…

  17. Wind energy and Turkey.

    PubMed

    Coskun, Aynur Aydin; Türker, Yavuz Özhan

    2012-03-01

    The global energy requirement for sustaining economic activities, meeting social needs and social development is increasing daily. Environmentally friendly, renewable energy resources are an alternative to the primary non-renewable energy resources, which devastate ecosystems in order to meet increasing demand. Among renewable energy sources such as hydropower, biopower, geothermal power and solar power, wind power offers distinct advantages to Turkey. There is an increasing tendency toward wind globally and the European Union adjusted its legal regulations in this regard. As a potential EU Member state, Turkey is going through a similar process. The number of institutional and legal regulations concerning wind power has increased in recent years; technical infrastructure studies were completed, and some important steps were taken in this regard. This study examines the way in which Turkey has developed support for wind power, presents a SWOT analysis of the wind power sector in Turkey and a projection was made for the concrete success expected to be accomplished in the future. PMID:21479556

  18. Osteomyelitis in turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Turkey osteomyelitis complex (TOC) is a condition in which apparently healthy, usually male birds have infections that are hidden in their bones, joints, and muscles. Some of these birds have a green liver, which provides a method for detecting these carcasses in the processing plant. Our research h...

  19. Cloning Creationism in Turkey.

    ERIC Educational Resources Information Center

    Edis, Taner

    1999-01-01

    Defines how political balances and changes in Turkey effect creation-evolution relation. Describes the influences of Bilim Arastirma Vakfi (BAV) on these changes, which are directly targeted to public education, and discusses the content of creationism. Questions why Islamic creationism is a copy of that of the Institute for Creation Research…

  20. Special Education in Turkey

    ERIC Educational Resources Information Center

    Eres, Figen

    2010-01-01

    The quality and the prevalence of education are the major indicators of the development of a society. It is a kind of human right to every person living in the society to be educated in a sufficient way. The education of the disabled people, a social reality in Turkey, is not sufficiently carried out. This paper aims at the education of the…

  1. Astronomy in Modern Turkey

    NASA Astrophysics Data System (ADS)

    Eker, Zeki; Demircan, Osman, Kirbiyik, Halil; Bilir, Selcuk

    2013-01-01

    Present-day astronomy and its development in the recent history of Turkey are described. Current astronomy education in modern-day Turkish Republic from primary to high schools, including modern-day university education is discussed. Astronomical and space research together with the existing observatories and present-day Turkish astronomy in the global state is presented.

  2. Axiom turkey genotyping array

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Axiom®Turkey Genotyping Array interrogates 643,845 probesets on the array, covering 643,845 SNPs. The array development was led by Dr. Julie Long of the USDA-ARS Beltsville Agricultural Research Center under a public-private partnership with Hendrix Genetics, Aviagen, and Affymetrix. The Turk...

  3. Apical blebs on sperm-storage tubule epithelial cell microvilli: their release and interaction with resident sperm in the turkey hen oviduct

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Technical Abstract: Located at the anterior end of the turkey hen vagina are numerous discrete tubular invaginations of the surface epithelium, collectively referred to as the sperm-storage tubules (SSTs). Following mating or artificial insemination, sperm ascend the vagina, enter the SSTs, and ove...

  4. Elevated in vivo levels of a single transcription factor directly convert satellite glia into oligodendrocyte-like cells.

    PubMed

    Weider, Matthias; Wegener, Amélie; Schmitt, Christian; Küspert, Melanie; Hillgärtner, Simone; Bösl, Michael R; Hermans-Borgmeyer, Irm; Nait-Oumesmar, Brahim; Wegner, Michael

    2015-02-01

    Oligodendrocytes are the myelinating glia of the central nervous system and ensure rapid saltatory conduction. Shortage or loss of these cells leads to severe malfunctions as observed in human leukodystrophies and multiple sclerosis, and their replenishment by reprogramming or cell conversion strategies is an important research aim. Using a transgenic approach we increased levels of the transcription factor Sox10 throughout the mouse embryo and thereby prompted Fabp7-positive glial cells in dorsal root ganglia of the peripheral nervous system to convert into cells with oligodendrocyte characteristics including myelin gene expression. These rarely studied and poorly characterized satellite glia did not go through a classic oligodendrocyte precursor cell stage. Instead, Sox10 directly induced key elements of the regulatory network of differentiating oligodendrocytes, including Olig2, Olig1, Nkx2.2 and Myrf. An upstream enhancer mediated the direct induction of the Olig2 gene. Unlike Sox10, Olig2 was not capable of generating oligodendrocyte-like cells in dorsal root ganglia. Our findings provide proof-of-concept that Sox10 can convert conducive cells into oligodendrocyte-like cells in vivo and delineates options for future therapeutic strategies. PMID:25680202

  5. Elevated In Vivo Levels of a Single Transcription Factor Directly Convert Satellite Glia into Oligodendrocyte-like Cells

    PubMed Central

    Weider, Matthias; Wegener, Amélie; Schmitt, Christian; Küspert, Melanie; Hillgärtner, Simone; Bösl, Michael R.; Hermans-Borgmeyer, Irm; Nait-Oumesmar, Brahim; Wegner, Michael

    2015-01-01

    Oligodendrocytes are the myelinating glia of the central nervous system and ensure rapid saltatory conduction. Shortage or loss of these cells leads to severe malfunctions as observed in human leukodystrophies and multiple sclerosis, and their replenishment by reprogramming or cell conversion strategies is an important research aim. Using a transgenic approach we increased levels of the transcription factor Sox10 throughout the mouse embryo and thereby prompted Fabp7-positive glial cells in dorsal root ganglia of the peripheral nervous system to convert into cells with oligodendrocyte characteristics including myelin gene expression. These rarely studied and poorly characterized satellite glia did not go through a classic oligodendrocyte precursor cell stage. Instead, Sox10 directly induced key elements of the regulatory network of differentiating oligodendrocytes, including Olig2, Olig1, Nkx2.2 and Myrf. An upstream enhancer mediated the direct induction of the Olig2 gene. Unlike Sox10, Olig2 was not capable of generating oligodendrocyte-like cells in dorsal root ganglia. Our findings provide proof-of-concept that Sox10 can convert conducive cells into oligodendrocyte-like cells in vivo and delineates options for future therapeutic strategies. PMID:25680202

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

    NASA Technical Reports Server (NTRS)

    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.

  7. Nursing in Turkey.

    PubMed

    Baumann, Steven L

    2006-10-01

    The current discussion on the nursing shortage needs to focus as much on nursing job satisfaction and retention as on nursing recruitment and education. Selected aspects of the motivational psychology of Abraham Maslow, Mihaly Csikszentmihalyi, and Frederick Hertzberg are here discussed in light of the challenges-opportunities of nursing in Turkey and elsewhere. Also discussed is an innovative program to support the application of nursing theory and professional development in Toronto, Canada. PMID:16982724

  8. Satellite communications

    NASA Astrophysics Data System (ADS)

    Rubin, Philip A.

    A review of the economic and technological status of the satellite communications industry is presented. The history of satellite communications is outlined, focusing on the launching of Syncom III in 1963. The basic operation of communication satellites is explained. The differences between C and Ku frequency bands are examined. Economic issues related to satellite communications are discussed in detail.

  9. Satellite communications

    NASA Astrophysics Data System (ADS)

    Saha, M. K.

    1982-11-01

    The paper describes the basic principles and the historial development of satellite communications. Various satellite systems for global communications are discused and compared. Some typical operational communication satellite systems summary including geostationary systems are presented. Considerations leading to the system design including the link design for various multiple access techniques and the future trends in satellite communications systems are also discussed.

  10. 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

    NASA Technical Reports Server (NTRS)

    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.

  11. Solar power satellite system definition study. Volume 4: Silicon solar cell annealing test, phase 1

    NASA Technical Reports Server (NTRS)

    Walker, F.

    1979-01-01

    Laser annealing tests were conducted on ten 50 micron cells. Two were control cells that were not irradiated. These showed no loss in output due to exposure to the laser. Two cells were broken in handling. Six cells were successfully tested. All cells tested without breakage showed some recovery. One cell was subjected to two cycles and showed recovery on both cycles. Cells that were moderately degraded appeared to recover more completely than those more severly degraded. Exposure times ranged from two to ten seconds at 500 degrees centigrade. There was some indication that longer exposure was beneficial.

  12. Greece and Turkey

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Summer is in full swing in this stunning true-color image of the southeastern European countries and Turkey captured by MODIS on June 29, 2002. Clockwise from left, the mountains of Greece, Albania, Macedonia, Yugoslavia, Bulgaria, and Turkey are swathed in brilliant greens and shades of golden brown; meanwhile (counterclockwise from left) the Ionian, Mediterranean, Aegean, and Black Seas are beautifully blue and green.Running diagonally across the image from the bottom middle to the top right is a gray streak that is caused by the angle of reflection of the sun on the water (called sun glint). The darker areas within this gray swath denote calmer water, and make visible currents that would not otherwise be noticeable.Surprisingly few fires were burning hot enough to be detectable by MODIS when this image was acquired during the height of the summer dry season. A single fire is visible burning in mainland Greece, six are visible in northwestern Turkey, and one burns on the western coast (marked with red outlines). Credit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC

  13. 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?

    PubMed

    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

  14. Refugee movements and Turkey.

    PubMed

    Kirisci, K

    1991-12-01

    There has been a long tradition in the Ottoman Empire and the Turkish Republic of receiving refugees. There were Jewish refugees from the Spanish Inquisition, Hungarians and Poles fleeing revolts in 1848-9, and those of Turkish descent and usually from the Balkans. Concurrent with this trend is the history of refugees and immigrants leaving Turkey, such as many Armenians, Greeks and Jews leaving at the turn of the century, and after 1923 and the Treaty of Lausanne. Little is currently published on the topic. This article defines a refugee; provides an overview of the refugee problems of the 1980's due to Bulgarian, Kurdish, and Turkish refugees; and the legal and political aspects. As a country of origin, there is discussion of the political and economic aspects of Turkish asylum seekers in Europe. The potential refugee flows to and from Turkey are also examined. I) For this study, refugees are victims of political violence and are persecuted for political or religious beliefs, ethnic or racial background, or war. In Turkey, there are national refugees, international refugees outside the Convention, and UNHCR Convention refugees. During the 1980's all 3 groups were arriving: from eastern Europe, Iranian Kurds, Iraqis, and ethnic Turks from Bulgaria and Afghanistan. The Turkish restricted acceptance of the 1951 Convention on Refugees creates serious humanitarian and security consequences for refugees other than those from eastern Europe and of Turkish ethnicity. Political considerations play an important role in treatment where security threats outweigh humanitarian need. The case is given for Kurdish refugees. II) Asylum seekers from Turkey in Western Europe was determined between 1986-90 to be 185,000 from applications. These figures have risen steadily due to the political instability and military activity of areas bordering Iraq and Syria, the Emergency Region. In addition there are economic and employment problems, and there has been a suspension of human

  15. Isolation of Mouse Periocular Tissue for Histological and Immunostaining Analyses of the Extraocular Muscles and Their Satellite Cells.

    PubMed

    Stuelsatz, Pascal; Yablonka-Reuveni, Zipora

    2016-01-01

    The extraocular muscles (EOMs) comprise a group of highly specialized skeletal muscles controlling eye movements. Although a number of unique features of EOMs including their sparing in Duchenne muscular dystrophy have drawn a continuous interest, knowledge about these hard to reach muscles is still limited. The goal of this chapter is to provide detailed methods for the isolation and histological analysis of mouse EOMs. We first introduce in brief the basic anatomy and established nomenclature of the extraocular primary and accessory muscles. We then provide a detailed description with step-by-step images of our procedure for isolating (and subsequently cryosectioning) EOMs while preserving the integrity of their original structural organization. Next, we present several useful histological protocols frequently used by us, including: (1) a method for highlighting the general organization of periocular tissue, using the MyoD(Cre) × R26(mTmG) reporter mouse that elegantly distinguishes muscle (MyoD(Cre)-driven GFP(+)) from the non-myogenic constituents (Tomato(+)); (2) analysis by H&E staining, allowing for example, detection of the pathological features of the dystrophin-null phenotype in affected limb and diaphragm muscles that are absent in EOMs; (3) detection of the myogenic progenitors (i.e., satellite cells) in their native position underneath the myofiber basal lamina using Pax7/laminin double immunostaining. The EOM tissue harvesting procedure described here can also be adapted for isolating and studying satellite cells and other cell types. Overall, the methods described in this chapter should provide investigators the necessary tools for entering the EOM research field and contribute to a better understanding of this highly specialized muscle group and its complex micro-anatomy. PMID:27492169

  16. Satellite battery testing status

    NASA Technical Reports Server (NTRS)

    Haag, R.; Hall, S.

    1986-01-01

    Because of the large numbers of satellite cells currently being tested and anticipated at the Naval Weapons Support Center (NAVWPNSUPPCEN) Crane, Indiana, satellite cell testing is being integrated into the Battery Test Automation Project (BTAP). The BTAP, designed to meet the growing needs for battery testing at the NAVWPNSUPPCEN Crane, will consist of several Automated Test Stations (ATSs) which monitor batteries under test. Each ATS will interface with an Automation Network Controller (ANC) which will collect test data for reduction.

  17. A new immuno-, dystrophin-deficient model, the NSG-mdx(4Cv) mouse, provides evidence for functional improvement following allogeneic satellite cell transplantation.

    PubMed

    Arpke, Robert W; Darabi, Radbod; Mader, Tara L; Zhang, Yu; Toyama, Akira; Lonetree, Cara-Lin; Nash, Nardina; Lowe, Dawn A; Perlingeiro, Rita C R; Kyba, Michael

    2013-08-01

    Transplantation of a myogenic cell population into an immunodeficient recipient is an excellent way of assessing the in vivo muscle-generating capacity of that cell population. To facilitate both allogeneic and xenogeneic transplantations of muscle-forming cells in mice, we have developed a novel immunodeficient muscular dystrophy model, the NSG-mdx(4Cv) mouse. The IL2Rg mutation, which is linked to the Dmd gene on the X chromosome, simultaneously depletes NK cells and suppresses thymic lymphomas, issues that limit the utility of the SCID/mdx model. The NSG-mdx(4Cv) mouse presents a muscular dystrophy of similar severity to the conventional mdx mouse. We show that this animal supports robust engraftment of both pig and dog muscle mononuclear cells. The question of whether satellite cells prospectively isolated by flow cytometry can confer a functional benefit upon transplantation has been controversial. Using allogeneic Pax7-ZsGreen donors and NSG-mdx(4Cv) recipients, we demonstrate definitively that as few as 900 FACS-isolated satellite cells can provide functional regeneration in vivo, in the form of an increased mean maximal force-generation capacity in cell-transplanted muscles, compared to a sham-injected control group. These studies highlight the potency of satellite cells to improve muscle function and the utility of the NSG-mdx(4Cv) model for studies on muscle regeneration and Duchenne muscular dystrophy therapy. PMID:23606600

  18. Movement ecology of migration in turkey vultures

    PubMed Central

    Mandel, J. T.; Bildstein, K. L.; Bohrer, G.; Winkler, D. W.

    2008-01-01

    We develop individual-based movement ecology models (MEM) to explore turkey vulture (Cathartes aura) migration decisions at both hourly and daily scales. Vulture movements in 10 migration events were recorded with satellite-reporting GPS sensors, and flight behavior was observed visually, aided by on-the-ground VHF radio-tracking. We used the North American Regional Reanalysis dataset to obtain values for wind speed, turbulent kinetic energy (TKE), and cloud height and used a digital elevation model for a measure of terrain ruggedness. A turkey vulture fitted with a heart-rate logger during 124 h of flight during 38 contiguous days showed only a small increase in mean heart rate as distance traveled per day increased, which suggests that, unlike flapping, soaring flight does not lead to greatly increased metabolic costs. Data from 10 migrations for 724 hourly segments and 152 daily segments showed that vultures depended heavily upon high levels of TKE in the atmospheric boundary layer to increase flight distances and maintain preferred bearings at both hourly and daily scales. We suggest how the MEM can be extended to other spatial and temporal scales of avian migration. Our success in relating model-derived atmospheric variables to migration indicates the potential of using regional reanalysis data, as here, and potentially other regional, higher-resolution, atmospheric models in predicting changing movement patterns of soaring birds under various scenarios of climate and land use change. PMID:19060195

  19. Reduced Toxicity Fuel Satellite Propulsion System Including Fuel Cell Reformer with Alcohols Such as Methanol

    NASA Technical Reports Server (NTRS)

    Schneider, Steven J. (Inventor)

    2001-01-01

    A reduced toxicity fuel satellite propulsion system including a reduced toxicity propellant supply for consumption in an axial class thruster and an ACS class thruster. The system includes suitable valves and conduits for supplying the reduced toxicity propellant to the ACS decomposing element of an ACS thruster. The ACS decomposing element is operative to decompose the reduced toxicity propellant into hot propulsive gases. In addition the system includes suitable valves and conduits for supplying the reduced toxicity propellant to an axial decomposing element of the axial thruster. The axial decomposing element is operative to decompose the reduced toxicity propellant into hot gases. The system further includes suitable valves and conduits for supplying a second propellant to a combustion chamber of the axial thruster, whereby the hot gases and the second propellant auto-ignite and begin the combustion process for producing thrust.

  20. Nutritional rickets in Turkey.

    PubMed

    Ozkan, Behzat

    2010-08-01

    Nutritional rickets (NR) remains the most common form of developmental bone disease, in spite of the efforts of clinicians and health care providers to reduce the incidence of the disease in Turkey. Today, it is well known that the etiology of NR exists along a spectrum ranging from isolated vitamin D deficiency to isolated calcium deficiency. In Turkey, almost all NR results from vita-min D deficiency that may have temporary but profound effects on short- and long-term skeletal development. Recent evidence suggests that vitamin D deficiency during infancy may predispose a patient to diseases such as diabetes mellitus, cancer, multiple sclerosis, etc. The factors responsible for the high prevalence of vitamin D deficiency in developing countries and its resurgence in developed countries include the following: limited sunshine exposure as individuals spend more time indoors watching television and working on computers or intentional sunshine avoidance for skin cancer prevention. Traditional clothing (covered dress) further limits the exposure to sunshine and thus decreases the endogenous synthesis of vitamin D. In Turkey, maternal vitamin D deficiency and breast feeding without supplementation are the most prominent reasons. The diagnosis of NR is established with a thorough history and physical examination and confirmed by laboratory evaluation. In conclusion, recent literature has drawn attention to the supplemental doses of vitamin D required to achieve a serum 25-hydroxyvitamin D level of at least 20 ng/ml (50 nmol/l), the serum concentration that is needed to optimize absorption of dietary calcium, suppress excess secretion of parathyroid hormone, and reduce fracture risk as well as prevent long-term negative effects. PMID:25610130

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

    PubMed Central

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

    2014-01-01

    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 < 0.01) and exhibited a group difference from Ecc (P < 0.05), which did not increase. Myonuclei content in type I fibers increased in all groups (P < 0.01), while a specific accretion of myonuclei in type II fibers was observed in the Whey-Conc (P < 0.01) and Placebo-Ecc (P < 0.01) groups. Similarly, whereas type I fiber CSA increased independently of intervention (P < 0.001), type II fiber CSA increased exclusively with Whey-Conc (P < 0.01) and type II fiber hypertrophy correlated with whole muscle hypertrophy exclusively following Conc training (P < 0.01). In conclusion, isolated concentric knee extensor resistance training appears to constitute a stronger driver of SC content than eccentric resistance training while type II fiber hypertrophy was accentuated when combining concentric resistance training with whey protein supplementation. PMID:25103976

  2. Tissue-Engineered External Anal Sphincter Using Autologous Myogenic Satellite Cells and Extracellular Matrix: Functional and Histological Studies.

    PubMed

    Kajbafzadeh, Abdol-Mohammad; Kajbafzadeh, Majid; Sabetkish, Shabnam; Sabetkish, Nastaran; Tavangar, Seyyed Mohammad

    2016-05-01

    The aim of the present study was to demonstrate the regaining histological characteristics of bioengineered external anal sphincters (EAS) in rabbit fecal incontinence model. The EAS of 16 rabbits were resected and decellularized. The decellularized scaffolds were transplanted to the terminal rectum following a period of 6 months of fecal incontinency (5 days after sterilization). The rabbits were divided into two groups: in group 1 (n = 8), myogenic satellite cells were injected into the transplanted sphincters. In group 2 (n = 8), the transplanted scaffolds remained in situ without cellular injection. The histological evaluation was performed with desmin, myosin, smooth muscle actin, CD31, and CD34 at 3-month intervals. The rabbits were followed for 2 years. Electromyography (EMG) with needle and electrical stimulation, pudendal and muscle electrical stimulation were also performed after 2 years of transplantation. At the time of biopsy, no evidence of inflammation or rejection was observed and the transplanted EAS appeared histologically and anatomically normal. The immunohistochemistry staining validated that the histological features of EAS was more satisfactory in group 1 in short-term follow-up. However, no statistically significant difference was detected between two groups in long-term follow-ups (p value > 0.05). In both groups, grafted EAS contracted in response to electrical signals delivered to the muscle and the pudendal nerve. However, more signals were detected in group 1 in EMG evaluation. In conclusion, bioengineered EAS with myogenic satellite cells can gain more satisfactory histological outcomes in short-term follow-ups with better muscle electrical stimulation outcomes. PMID:26424474

  3. Heat stress inhibits proliferation, promotes growth, and induces apoptosis in cultured Lantang swine skeletal muscle satellite cells.

    PubMed

    Gao, Chun-qi; Zhao, Yin-ling; Li, Hai-chang; Sui, Wei-guo; Yan, Hui-chao; Wang, Xiu-qi

    2015-06-01

    Proliferation suppression and apoptosis are the prominent characteristics induced by heat stress (HS) in cells, whereas the effects of HS on cell growth (mass accumulation) are unknown. In this study, Lantang swine (an indigenous breed of China) skeletal muscle satellite cells (SCs) were pre-cultured at 37 °C for 24 h. The HS group was subjected to HS at 41 °C, while the control group was maintained at 37 °C. Heat shock protein 70 (HSP70) expression and SC size are significantly increased (P<0.05) by HS, but cell proliferation is suppressed (P<0.05) and apoptosis is induced (P<0.05). HS led to a lower percentage of SCs in the G0/G1 phase (P<0.05) together with a higher percentage of SCs in the S phase (P<0.05). However, the percentage of SCs in the G2/M phase was decreased (P<0.05) at 48 h but then increased (P<0.05) at 72 h with HS. In addition, the phosphorylation ratios of protein kinase b (Akt), ribosomal protein S6 kinase (S6K), and ribosomal protein S6 were increased (P<0.05) by HS. Nevertheless, the phosphorylation ratios of the 4E binding protein 1 and the eukaryotic initiation factor-4E were indistinguishable (P>0.05) from those of the control group. The phosphorylation ratio of the mammalian target of rapamycin (mTOR) (Ser(2448)) increased (P<0.05) within 48 h, and apparent differences were abrogated at 72 h (P>0.05). Moreover, cleaved caspase-3 expression was increased at 72 h (P<0.05). These findings indicate that HS induces apoptosis and disrupts cell cycle distribution to decrease the number of cells. Additionally, HS can promote SC growth via an activated Akt/mTOR/S6K signaling pathway. PMID:26055917

  4. Harsh Winter in Turkey

    NASA Technical Reports Server (NTRS)

    2002-01-01

    The predominantly mountainous terrain of the Republic of Turkey is covered by snow in this Moderate-resolution Imaging Spectroradiometer (MODIS) true-color image, produced from data collected on January 13, 2002. The snow-laced peaks of the Kure Daglari mountain range in the north can be seen as they range from the upper middle of the image to the upper right. The mountains parallel the northern coastline, which opens to the Black Sea. Also visible in this image, at the bottom right, is the island of Cyprus. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  5. Optimum conditions for the turkey lymphocyte transformation test.

    PubMed

    Barta, O; Barta, V; Domermuth, C H; Pierson, F W

    1992-01-01

    Optimum conditions for turkey lymphocyte transformation tests were determined. Thrice-washed turkey buffy-coat cells obtained after slow centrifugation (40 x g, 10 minutes) responded well to mitogenic stimulation. Turkey lymphocytes isolated on Ficoll-containing separation media largely lost their ability to respond to mitogens. Maximum responses were obtained with 2 x 10(7) lymphoid cells/ml. Responses to the mitogens were greatest when bovine fetal serum was used at a 2.5% concentration or pooled turkey serum and autologous plasma were used at a 1.25% concentration. Higher concentrations of turkey serum or plasma decreased the responses when sub-optimum doses of concanavalin-A (Con A) or phytohemagglutinin-P (PHA-P) were used. Serum-free cultures gave higher stimulation indices than cultures with serum only when sub-optimum doses of Con A or PHA-P were used. Optimum mitogen concentrations varied with individual birds, timing of the culture, temperature of incubation, and serum concentration in the cultures. Responses were usually greatest with final concentrations of 5 micrograms Con A/ml, 10 micrograms PHA-P/ml, and 20 micrograms pokeweed mitogen (PWM)/ml and when the cultures were incubated in 96-well microplates at 40 C in humidified air with 5% CO2 for 40-42 hours with pulsing with 3H-thymidine during the final 16 hours of incubation. PMID:1627110

  6. Development works on nickel/hydrogen cells. [for satellite energy storage

    NASA Technical Reports Server (NTRS)

    Gutmann, G.

    1982-01-01

    Experiments were performed to reduce the costs for NI/H2 cells by using nickel oxide electrodes with high capacity per unit area. No maintenance requirements, long cycle life, insensitivity to overcharge and cell reversal, and high power capability were revealed.

  7. Activation of satellite cells and the regeneration of human skeletal muscle are expedited by ingestion of nonsteroidal anti-inflammatory medication.

    PubMed

    Mackey, Abigail L; Rasmussen, Lotte K; Kadi, Fawzi; Schjerling, Peter; Helmark, Ida C; Ponsot, Elodie; Aagaard, Per; Durigan, João Luiz Q; Kjaer, Michael

    2016-06-01

    With this study we investigated the role of nonsteroidal anti-inflammatory drugs (NSAIDs) in human skeletal muscle regeneration. Young men ingested NSAID [1200 mg/d ibuprofen (IBU)] or placebo (PLA) daily for 2 wk before and 4 wk after an electrical stimulation-induced injury to the leg extensor 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 with PLA, IBU was found to augment the proportion of ActiveNotch1(+) satellite cells at 2 d [IBU, 29 ± 3% vs. PLA, 19 ± 2% (means ± sem)], satellite cell content at 7 d [IBU, 0.16 ± 0.01 vs. PLA, 0.12 ± 0.01 (Pax7(+) cells/fiber)], and to expedite muscle repair at 30 d. The PLA group displayed a greater proportion of embryonic myosin(+) fibers and a residual ∼2-fold increase in mRNA levels of matrix proteins (all P < 0.05). Endomysial collagen was also elevated with PLA at 30 d. Minimum telomere length shortening was not observed. In conclusion, ingestion of NSAID has a potentiating effect on Notch activation of satellite cells and muscle remodeling during large-scale regeneration of injured human skeletal muscle.-Mackey, A. L., Rasmussen, L. K., Kadi, F., Schjerling, P., Helmark, I. C., Ponsot, E., Aagaard, P., Durigan, J. L. Q., Kjaer, M. Activation of satellite cells and the regeneration of human skeletal muscle are expedited by ingestion of nonsteroidal anti-inflammatory medication. PMID:26936358

  8. Recent activity in Turkey.

    PubMed

    1987-01-01

    The role of Pathfinder grants to recent family planning projects led by business and labor in Turkey is described. Pathfinder funded a major portion of the Turkish Family Planning and Health Foundation, a grant agency set up to complement government programs. One current project is a survey of family planning needs of squatter communities. The Foundation's founder established a factory-based family planning clinic, aided by Pathfinder, now self-supporting. The Turkish TURK-IS Labor Federation has supported several other worksite clinics, and has placed family planning among its top priorities. Pathfinder supported development of their population policy statement. Turkey has only recently passed progressive family planning legislation and permitted significant private sector activities. The population of 52 million is growing at 2.8%. Unemployment is high; per capita income is $1160. The government's goals are to reduce fertility from 4.3 to 2.5 children per woman and increase contraceptive prevalence from 20% to 60% by the year 2000. PMID:12179678

  9. Evaluation of solar cells and arrays for potential solar power satellite applications

    NASA Technical Reports Server (NTRS)

    Almgren, D. W.; Csigi, K.; Gaudet, A. D.

    1978-01-01

    Proposed solar array designs and manufacturing methods are evaluated to identify options which show the greatest promise of leading up to the develpment of a cost-effective SPS solar cell array design. The key program elements which have to be accomplished as part of an SPS solar cell array development program are defined. The issues focussed on are: (1) definition of one or more designs of a candidate SPS solar array module, using results from current system studies; (2) development of the necessary manufacturing requirements for the candidate SPS solar cell arrays and an assessment of the market size, timing, and industry infrastructure needed to produce the arrays for the SPS program; (3) evaluation of current DOE, NASA and DOD photovoltaic programs to determine the impacts of recent advances in solar cell materials, array designs and manufacturing technology on the candidate SPS solar cell arrays; and (4) definition of key program elements for the development of the most promising solar cell arrays for the SPS program.

  10. Community effect triggers terminal differentiation of myogenic cells derived from muscle satellite cells by quenching Smad signaling

    SciTech Connect

    Yanagisawa, Michiko; Mukai, Atsushi; Shiomi, Kosuke; Song, Si-Yong; Hashimoto, Naohiro

    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.

  11. Sphingosine-1-Phosphate Enhances Satellite Cell Activation in Dystrophic Muscles through a S1PR2/STAT3 Signaling Pathway

    PubMed Central

    Carlson, Morgan E.; Oskouian, Babak; Kumar, Ashok; Fyrst, Henrik; Zhang, Meng; Proia, Richard L.; Hoffman, Eric P.; Saba, Julie D.

    2012-01-01

    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. PMID:22606352

  12. Sphingosine-1-phosphate enhances satellite cell activation in dystrophic muscles through a S1PR2/STAT3 signaling pathway.

    PubMed

    Loh, Kenneth C; Leong, Weng-In; Carlson, Morgan E; Oskouian, Babak; Kumar, Ashok; Fyrst, Henrik; Zhang, Meng; Proia, Richard L; Hoffman, Eric P; Saba, Julie D

    2012-01-01

    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. PMID:22606352

  13. STAT3 Regulates Self-Renewal of Adult Muscle Satellite Cells during Injury-Induced Muscle Regeneration.

    PubMed

    Zhu, Han; Xiao, Fang; Wang, Gang; Wei, Xiuqing; Jiang, Lei; Chen, Yan; Zhu, Lin; Wang, Haixia; Diao, Yarui; Wang, Huating; Ip, Nancy Y; Cheung, Tom H; Wu, Zhenguo

    2016-08-23

    Recent studies have shown that STAT3 negatively regulates the proliferation of muscle satellite cells (MuSCs) and injury-induced muscle regeneration. These studies have been largely based on STAT3 inhibitors, which may produce off-target effects and are not cell type-specific in vivo. Here, we examine the role of STAT3 in MuSCs using two different mouse models: a MuSC-specific Stat3 knockout line and a Stat3 (MuSC-specific)/dystrophin (Dmd) double knockout (dKO) line. Stat3(-/-) MuSCs from both mutant lines were defective in proliferation. Moreover, in both mutant strains, the MuSC pool shrank, and regeneration was compromised after injury, with defects more pronounced in dKO mice along with severe muscle inflammation and fibrosis. We analyzed the transcriptomes of MuSCs from dKO and Dmd(-/-) control mice and identified multiple STAT3 target genes, including Pax7. Collectively, our work reveals a critical role of STAT3 in adult MuSCs that regulates their self-renewal during injury-induced muscle regeneration. PMID:27524611

  14. Extracellular Vesicles: Satellites of Information Transfer in Cancer and Stem Cell Biology.

    PubMed

    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. PMID:27219060

  15. Hepatic Transcriptome Responses of Domesticated and Wild Turkey Embryos to Aflatoxin B1

    PubMed Central

    Monson, Melissa S.; Cardona, Carol J.; Coulombe, Roger A.; Reed, Kent M.

    2016-01-01

    The mycotoxin, aflatoxin B1 (AFB1) is a hepatotoxic, immunotoxic, and mutagenic contaminant of food and animal feeds. In poultry, AFB1 can be maternally transferred to embryonated eggs, affecting development, viability and performance after hatch. Domesticated turkeys (Meleagris gallopavo) are especially sensitive to aflatoxicosis, while Eastern wild turkeys (M. g. silvestris) are likely more resistant. In ovo exposure provided a controlled AFB1 challenge and comparison of domesticated and wild turkeys. Gene expression responses to AFB1 in the embryonic hepatic transcriptome were examined using RNA-sequencing (RNA-seq). Eggs were injected with AFB1 (1 μg) or sham control and dissected for liver tissue after 1 day or 5 days of exposure. Libraries from domesticated turkey (n = 24) and wild turkey (n = 15) produced 89.2 Gb of sequence. Approximately 670 M reads were mapped to a turkey gene set. Differential expression analysis identified 1535 significant genes with |log2 fold change| ≥ 1.0 in at least one pair-wise comparison. AFB1 effects were dependent on exposure time and turkey type, occurred more rapidly in domesticated turkeys, and led to notable up-regulation in cell cycle regulators, NRF2-mediated response genes and coagulation factors. Further investigation of NRF2-response genes may identify targets to improve poultry resistance. PMID:26751476

  16. Hepatic Transcriptome Responses of Domesticated and Wild Turkey Embryos to Aflatoxin B₁.

    PubMed

    Monson, Melissa S; Cardona, Carol J; Coulombe, Roger A; Reed, Kent M

    2016-01-01

    The mycotoxin, aflatoxin B₁ (AFB₁) is a hepatotoxic, immunotoxic, and mutagenic contaminant of food and animal feeds. In poultry, AFB₁ can be maternally transferred to embryonated eggs, affecting development, viability and performance after hatch. Domesticated turkeys (Meleagris gallopavo) are especially sensitive to aflatoxicosis, while Eastern wild turkeys (M. g. silvestris) are likely more resistant. In ovo exposure provided a controlled AFB₁ challenge and comparison of domesticated and wild turkeys. Gene expression responses to AFB₁ in the embryonic hepatic transcriptome were examined using RNA-sequencing (RNA-seq). Eggs were injected with AFB₁ (1 μg) or sham control and dissected for liver tissue after 1 day or 5 days of exposure. Libraries from domesticated turkey (n = 24) and wild turkey (n = 15) produced 89.2 Gb of sequence. Approximately 670 M reads were mapped to a turkey gene set. Differential expression analysis identified 1535 significant genes with |log₂ fold change| ≥ 1.0 in at least one pair-wise comparison. AFB₁ effects were dependent on exposure time and turkey type, occurred more rapidly in domesticated turkeys, and led to notable up-regulation in cell cycle regulators, NRF2-mediated response genes and coagulation factors. Further investigation of NRF2-response genes may identify targets to improve poultry resistance. PMID:26751476

  17. Satellite RNAs and Satellite Viruses.

    PubMed

    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. PMID:26551994

  18. P2Y1 Receptor Activation of the TRPV4 Ion Channel Enhances Purinergic Signaling in Satellite Glial Cells.

    PubMed

    Rajasekhar, Pradeep; Poole, Daniel P; Liedtke, Wolfgang; Bunnett, Nigel W; Veldhuis, Nicholas A

    2015-11-27

    Transient receptor potential (TRP) ion channels of peripheral sensory pathways are important mediators of pain, itch, and neurogenic inflammation. They are expressed by primary sensory neurons and by glial cells in the central nervous system, but their expression and function in satellite glial cells (SGCs) of sensory ganglia have not been explored. SGCs tightly ensheath neurons of sensory ganglia and can regulate neuronal excitability in pain and inflammatory states. Using a modified dissociation protocol, we isolated neurons with attached SGCs from dorsal root ganglia of mice. SGCs, which were identified by expression of immunoreactive Kir4.1 and glutamine synthetase, were closely associated with neurons, identified using the pan-neuronal marker NeuN. A subpopulation of SGCs expressed immunoreactive TRP vanilloid 4 (TRPV4) and responded to the TRPV4-selective agonist GSK1016790A by an influx of Ca(2+) ions. SGCs did not express functional TRPV1, TRPV3, or TRP ankyrin 1 channels. Responses to GSK1016790A were abolished by the TRPV4 antagonist HC067047 and were absent in SGCs from Trpv4(-/-) mice. The P2Y1-selective agonist 2-methylthio-ADP increased [Ca(2+)]i in SGCs, and responses were prevented by the P2Y1-selective antagonist MRS2500. P2Y1 receptor-mediated responses were enhanced in TRPV4-expressing SGCs and HEK293 cells, suggesting that P2Y1 couples to and activates TRPV4. PKC inhibitors prevented P2Y1 receptor activation of TRPV4. Our results provide the first evidence for expression of TRPV4 in SGCs and demonstrate that TRPV4 is a purinergic receptor-operated channel in SGCs of sensory ganglia. PMID:26475857

  19. CCAAT/enhancer binding protein beta protects muscle satellite cells from apoptosis after injury and in cancer cachexia

    PubMed Central

    Marchildon, F; Fu, D; Lala-Tabbert, N; Wiper-Bergeron, N

    2016-01-01

    CCAAT/enhancer binding protein beta (C/EBPβ), a transcription factor expressed in muscle satellite cells (SCs), inhibits the myogenic program and is downregulated early in differentiation. In a conditional null model in which C/EBPβ expression is knocked down in paired box protein 7+ (Pax7+) SCs, cardiotoxin (CTX) injury is poorly repaired, although muscle regeneration is efficient in control littermates. While myoblasts lacking C/EBPβ can differentiate efficiently in culture, after CTX injury poor regeneration was attributed to a smaller than normal Pax7+ population, which was not due to a failure of SCs to proliferate. Rather, the percentage of apoptotic SCs was increased in muscle lacking C/EBPβ. Given that an injury induced by BaCl2 is repaired with greater efficiency than controls in the absence of C/EBPβ, we investigated the inflammatory response following BaCl2 and CTX injury and found that the levels of interleukin-1β (IL-1β), a proinflammatory cytokine, were robustly elevated following CTX injury and could induce C/EBPβ expression in myoblasts. High levels of C/EBPβ expression in myoblasts correlated with resistance to apoptotic stimuli, while its loss increased sensitivity to thapsigargin-induced cell death. Using cancer cachexia as a model for chronic inflammation, we found that C/EBPβ expression was increased in SCs and myoblasts of tumor-bearing cachectic animals. Further, in cachectic conditional knockout animals lacking C/EBPβ in Pax7+ cells, the SC compartment was reduced because of increased apoptosis, and regeneration was impaired. Our findings indicate that the stimulation of C/EBPβ expression by IL-1β following muscle injury and in cancer cachexia acts to promote SC survival, and is therefore a protective mechanism for SCs and myoblasts in the face of inflammation. PMID:26913600

  20. Low dose of IGF-I increases cell size of skeletal muscle satellite cells via Akt/S6K signaling pathway.

    PubMed

    Gao, Chun-qi; Zhi, Rui; Yang, Zhou; Li, Hai-chang; Yan, Hui-chao; Wang, Xiu-qi

    2015-11-01

    The objective of this study was to investigate the effect of insulin growth factor-I (IGF-I) on the size of pig skeletal muscle satellite cells (SCs). Using microarray, real-time RT-PCR, radioimmunoassay analysis and western blot, we first showed that supplementation of low-dose of IGF-I in culture medium resulted in enlarged cell size of Lantang SCs, only Akt and S6K were up-regulated at both the mRNA and protein levels among almost all of the mTOR pathway key genes, but had no effect on cell number. To elucidate the signaling mechanisms responsible for regulating cell size under low-dose of IGF-I treatment, we blocked Akt and S6K activity with the specific inhibitors MK2206 and PF4708671, respectively. Both inhibitors caused a decrease in cell size. In addition, MK2206 lowered the protein level of p-Akt (Ser473), p-S6K (Thr389), and p-rpS6 (Ser235/236), whereas PF4708671 lowered the protein level of p-S6K (Thr389) and p-rpS6 (Ser235/236). However, low dose of IGF-I didn't affect the protein level of p-mTOR (Ser2448) and p-mTOR (Ser2481). When both inhibitors were applied simultaneously, the effect was the same as that of the Akt inhibition alone. Taken together, we report for the first time that low-dose of IGF-I treatment increases cell size via Akt/S6K signaling pathway. PMID:25923195

  1. Alphoid satellite DNA is tightly associated with centromere antigens in human chromosomes throughout the cell cycle

    SciTech Connect

    Masumoto, Hiroshi; Sugimoto, Kenji; Okazaki, Tuneko )

    1989-03-01

    In this study, the authors have examined a DNA element specific to the centromere domain of human chromosomes. Purified HeLa chromosomes were digested with the restriction enzyme Sau3AI and fractionated by sedimentation through a sucrose gradient. Fractions showing antigenicity to anticentromere (kinetochore) serum obtained from a scleroderma CREST patient were used to construct a DNA library. From this library they found one clone which has specifically hybridized to the centromere domain of metaphase chromosomes using a biotinylated probe DNA and FITC-conjugated avidin. The clone contained a stretch of alphoid DNA dimer. To determine precisely the relative location of the alphoid DNA stretch and the centromere antigen, a method was developed to carry out in situ hybridization of DNA and indirect immunofluorescent staining of antigen on the same cell preparation. Using this method, they have found perfect overlapping of the alphoid DNA sites with the centromere antigen in both metaphase chromosomes and nuclei at various stages in the cell cycle. They have also observed this exact correlation at the attachment sites of artificially extended sister chromatids. These results suggest the possibility that alphoid DNA repeats are a key component of kinetochore structure.

  2. Influence of Pasteurella multocida and high and low environmental temperatures on adrenals and bursa of Fabricius in turkeys

    SciTech Connect

    Simensen, E.; Olson, L.D.; Hahn, G.L.

    1980-01-01

    The morphologic changes in the adrenals and bursa of Fabricius were evaluated from turkeys inoculated with Pasteurella multocida either in the palatine air spaces or via drinking water and maintained at high (33.4-37.4 C), low (2.6-5.3 C), and moderate (19.8-22.4 C) temperatures in temperature-controlled chambers. There was a slight hyperplasia of the adrenal cortical cells and a hypertrophy of the nuclei in the uninoculated turkeys maintained at both high and low temperatures, but these changes were more marked in turkeys maintained at low temperatures. Regardless of the temperature to which the turkeys were exposed, there was an increase in adrenal weight, hyperplasia of the cortical cells, hypertrophy of the nuclei of the cortical cells, and depletion of lipid in the cortical cells in the turkeys that became depressed after inoculation with P. multocida. In the uninoculated turkeys exposed to high temperatures there was a reduction in the weight of the bursa of Fabricius, atrophy of the follicles, and a reduction in the number of lymphocytes within the follicle, which did not occur in the bursae from uninoculated turkeys maintained at low temperatures. In the turkeys inoculated with P. multocida, there was a marked reduction in bursal weight, atrophy of the follicles, and reduction in the number of lymphocytes within the follicles.

  3. Angiogenesis as a novel therapeutic strategy for Duchenne muscular dystrophy through decreased ischemia and increased satellite cells

    PubMed Central

    Shimizu-Motohashi, Yuko; Asakura, Atsushi

    2014-01-01

    Duchenne muscular dystrophy (DMD) is the most common hereditary muscular dystrophy caused by mutation in dystrophin, and there is no curative therapy. Dystrophin is a protein which forms the dystrophin-associated glycoprotein complex (DGC) at the sarcolemma linking the muscle cytoskeleton to the extracellular matrix. When dystrophin is absent, muscle fibers become vulnerable to mechanical stretch. In addition to this, accumulating evidence indicates DMD muscle having vascular abnormalities and that the muscles are under an ischemic condition. More recent studies demonstrate decreased vascular densities and impaired angiogenesis in the muscles of murine model of DMD. Therefore, generation of new vasculature can be considered a potentially effective strategy for DMD therapy. The pro-angiogenic approaches also seem to be pro-myogenic and could induce muscle regeneration capacity through expansion of the satellite cell juxtavascular niche in the mouse model. Here, we will focus on angiogenesis, reviewing the background, vascular endothelial growth factor (VEGF)/VEGF receptor-pathway, effect, and concerns of this strategy in DMD. PMID:24600399

  4. Pax7 Reveals a Greater Frequency and Concentration of Satellite Cells at the Ends of Growing Skeletal Muscle Fibers

    PubMed Central

    Allouh, Mohammed Z.; Yablonka-Reuveni, Zipora; Rosser, Benjamin W.C.

    2008-01-01

    The main sites of longitudinal growth in skeletal muscle are the ends of the fibers. This study tests the hypothesis that satellite cells (SCs) are at a greater frequency (#SC nuclei/all nuclei within basal laminae) and concentration (closer together) within growing fiber ends of posthatch chicken pectoralis. SCs were localized by their Pax7 expression, and fiber ends were identified by their retention of neonatal myosin heavy chains and small cross-sectional profiles. Whereas SC frequency decreased from about 20% at 9 days posthatch to <5% at 115 days, fiber ends retained a frequency of ∼16%. Calculated mean area of sarcolemma per SC revealed higher concentrations of SCs at fiber ends. There was also a strong inverse correlation between SC frequency and fiber profile cross-sectional size throughout development. This study suggests that SCs at fiber ends play a key role in the longitudinal growth of muscle fibers, and that fiber profile size may impact SC distribution. (J Histochem Cytochem 56:77–87, 2008) PMID:17938281

  5. Heat shock factor 1 binds to and transcribes satellite II and III sequences at several pericentromeric regions in heat-shocked cells

    SciTech Connect

    Eymery, Angeline; INSERM Institut Albert Bonniot U823, La Tronche, F-38700 ; Souchier, Catherine; INSERM Institut Albert Bonniot U823, La Tronche, F-38700 ; Vourc'h, Claire; INSERM Institut Albert Bonniot U823, La Tronche, F-38700 ; Jolly, Caroline; INSERM Institut Albert Bonniot U823, La Tronche, F-38700

    2010-07-01

    Cells respond to stress by activating the synthesis of heat shock proteins (HSPs) which protect the cells against the deleterious effects of stress. This mechanism is controlled by the heat shock factor 1 (HSF1). In parallel to HSP gene transcription, in human cells, HSF1 also binds to and transcribes satellite III repeated sequences present in numerous copies in the 9q12 pericentromeric region of chromosome 9. These HSF1 accumulation sites are termed nuclear stress bodies (nSBs). In tumor cells, however, the number of nSBs is higher than the number of 9q12 copies, suggesting the existence of other HSF1 targets. In this paper, we were interested in characterizing these other HSF1 binding sites. We show that HSF1 indeed binds to the pericentromeric region of 14 chromosomes, thereby directing the formation of 'secondary nSBs'. The appearance of secondary nSBs depends on the number of satellite sequences present in the target locus, and on the cellular amount of HSF1 protein. Moreover, secondary nSBs also correspond to transcription sites, thus demonstrating that heat shock induces a genome-wide transcription of satellite sequences. Finally, by analyzing published transcriptomic data, we show that the derepression of these large heterochromatic blocks does not significantly affect the transcription of neighboring genes.

  6. Effects of Dexamethasone on Satellite Cells and Tissue Engineered Skeletal Muscle Units.

    PubMed

    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

  7. An empirical modeling of spatial distribution of trapped protons from solar cell degradation of the Akebono satellite

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

    Output current of silicon solar cells of Akebono satellite orbiting in the inner magnetosphere decreased from 13 A in 1989 to about 7 A in 2009, due to accumulated damage by energetic particles. Annual decrease from the same month in the previous year shows a clear oscillation due to orbit precession correlated with trapped energetic proton flux up to 1996. Although phase of the oscillation in annual variation shows a clear correlation, the amplitude tends to be larger than that expected from a degradation model based on energetic proton distribution of the NASA's AP8 model. We have worked on modeling of the L-shell distribution of trapped energetic protons which provides best-fit for the degradation of solar cells. The results by assuming Gaussian distribution of proton flux for L value are as follows. (1) If we assume a steady state before 1996, the best-fitted distribution has a peak around L = 1.6 and a width of dL = 0.1 (i.e., half width of 1/e decrease from the peak). (2) If we employ a dynamic model with temporal variation and introduce a different distribution between April 1991 and June 1992, RMSE is further improved from the static model. Modeled distributions have its center around L = 1.9, suggesting outward shift or expansion of the proton radiation belt during the interval. Our modeling gives more confined distribution than given by the AP8 and AP9 models, but is more consistent with the CRRESPRO model based on the observation before November 1991.

  8. Changes in proteolytic enzymes mRNAs and proteins relevant for meat quality during myogenesis and hypoxia of primary bovine satellite cells.

    PubMed

    Yang, You Bing; Pandurangan, Muthuraman; Hwang, InHo

    2012-06-01

    The current study was conducted to evaluate the functions of μ-calpain (CAPN1), calpastatin, HSPs (heat shock proteins), and caspases during myogenesis and cell death induced by sodium azide (NaN(3)) hypoxia. The cell samples were divided into three groups: satellite cells formed at confluent monolayer (stage 1), stage 1 cells fusion into myotubes on d eight post-differentiation (stage 2), and stage 2 cells treated with 1 mM NaN(3) for 24 h (stage 3). Real-time RT-PCR showed that stage 2 cells had increased CAPN1, calpastatin, caspase 7, and CARD9 (Caspase activation and recruitment domain 9) mRNA expressions compared to stage 1 cells (*p < 0.05). By Western blotting caspase 3, caspase 7, caspase 8, and caspase 9 protein levels increased in cells at stage 2 compared to cells at stage 1 (*p < 0.05). Real-time RT-PCR showed that stage 3 cells had increased CAPN1, calpastatin, caspase 7, HSP70 (70 kDA heat shock proteins), and HSP90 (90 kDA heat shock proteins-alpha) and decreased CARD9 mRNA expression compared to stage 2 cells (*p < 0.05). Stage 3 samples had increase caspase 7 and caspase 12 activities compared to stage 2 samples, and by Western blotting protein levels of both HSP70 and HSP90 expressions, increased significantly under hypoxia condition (*p < 0.05). Here, we conclude that CAPN1, calpastatin, caspase 3, caspase 7, caspase 8, and CARD9 have important roles for satellite cell myogenesis; and that caspase 7, 12, HSP70, and HSP90 are involved in the process of apoptotic cell death under hypoxia conditions and we speculate that these proteins may be involved in early postmortem proteolysis and meat tenderization. PMID:22648733

  9. Turkey. Health system review.

    PubMed

    Tatar, Mehtap; Mollahaliloğlu, Salih; Sahin, Bayram; Aydin, Sabahattin; Maresso, Anna; Hernández-Quevedo, Cristina

    2011-01-01

    Turkey has accomplished remarkable improvements in terms of health status in the last three decades, particularly after the implementation of the Health Transformation Program (HTP (Saglikta Donus, um Programi)). Average life expectancy reached 71.8 for men and 76.8 for women in 2010. The infant mortality rate (IMR) decreased to 10.1 per 1000 live births in 2010, down from 117.5 in 1980. Despite these achievements, there are still discrepancies in terms of infant mortality between rural and urban areas and different parts of the country, although these have been diminishing over the years. The higher infant mortality rates in rural areas can be attributed to low socioeconomic conditions, low female education levels and the prevalence of infectious diseases. The main causes of death are diseases of the circulatory system followed by malignant neoplasms. Turkeys health care system has been undergoing a far-reaching reform process (HTP) since 2003 and radical changes have occurred both in the provision and the financing of health care services. Health services are now financed through a social security scheme covering the majority of the population, the General Health Insurance Scheme (GHIS (Genel Saglik Sigortasi)), and services are provided both by public and private sector facilities. The Social Security Institution (SSI (Sosyal Guvenlik Kurumu)), financed through payments by employers and employees and government contributions in cases of budget deficit, has become a monopsonic (single buyer) power on the purchasing side of health care services. On the provision side, the Ministry of Health (Saglik Bakenligi) is the main actor and provides primary, secondary and tertiary care through its facilities across the country. Universities are also major providers of tertiary care. The private sector has increased its range over recent years, particularly after arrangements paved the way for private sector provision of services to the SSI. The most important reforms since

  10. Time's Up, Turkey--Pop-Up Thermometers

    ERIC Educational Resources Information Center

    Moyer, Richard; Everett, Susan

    2009-01-01

    Meat thermometers can be awkward to use in terms of placement and avoidance of bones. Because of these problems, each year 30 million Thanksgiving turkeys have a built-in thermometer that pops up when the turkey is properly cooked. Turkey timers are an example of how engineering solved a common, everyday problem. The following 5E learning cycle…

  11. An overview of tumorous diseases of turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This overview is primarily aimed at addressing various aspects of virus-induced tumorous diseases of turkeys including review of current methods for diagnosis and control of these diseases of turkeys. Virus-induced tumorous diseases of turkeys are caused primarily by retroviruses, namely reticuloend...

  12. Life Satisfaction and Happiness in Turkey

    ERIC Educational Resources Information Center

    Selim, Sibel

    2008-01-01

    This research aims to investigate life satisfaction and happiness in Turkey. It extends the previous researches on subjective well-being (SWB) for Turkey by considering both happiness and life satisfaction. The previous researches for Turkey are local studies, and their findings cannot be generalized to the population of Turkish society. Given…

  13. Turkey: Reviews of National Policies for Education.

    ERIC Educational Resources Information Center

    Organisation for Economic Cooperation and Development, Paris (France).

    The first of three parts of this review of Turkey's educational system and national educational policies, the examiner's report, begins by singling out essential features of modern Turkey that affect the provision of education and to which the system is having to respond. These include Turkey's unique geographic situation, its continuing devotion…

  14. Fourteen days of bed rest induces a decline in satellite cell content and robust atrophy of skeletal muscle fibers in middle-aged adults.

    PubMed

    Arentson-Lantz, Emily J; English, Kirk L; Paddon-Jones, Douglas; Fry, Christopher S

    2016-04-15

    Bed rest, a ground-based spaceflight analog, induces robust atrophy of skeletal muscle, an effect that is exacerbated with increasing age. We examined the effect of 14 days of bed rest on skeletal muscle satellite cell content and fiber type atrophy in middle-aged adults, an understudied age demographic with few overt signs of muscle aging that is representative of astronauts who perform long-duration spaceflight. Muscle biopsies were obtained from the vastus lateralis of healthy middle-aged adults [n= 7 (4 male, 3 female); age: 51 ± 1 yr] before (Pre-BR) and after (Post-BR) 14 days of bed rest. Immunohistochemical analyses were used to quantify myosin heavy chain (MyHC) isoform expression, cross-sectional area (CSA), satellite cell and myonuclear content, and capillary density. Peak oxygen consumption, knee extensor strength, and body composition were also measured Pre-BR and Post-BR. Post-BR MyHC type 2a fiber percentage was reduced, and mean CSA decreased in all fiber types (-24 ± 5%;P< 0.05). Satellite cell content was also reduced Post-BR (-39 ± 9%;P< 0.05), and the change in satellite cell content was significantly correlated with the change in mean fiber CSA (r(2)= 0.60;P< 0.05). A decline in capillary density was observed Post-BR (-23 ± 6%;P< 0.05), and Post-BR capillary content was significantly associated with Post-BR peak aerobic capacity (r(2)= 0.59;P< 0.05). A subtle decline in myonuclear content occurred during bed rest (-5 ± 1%;P< 0.05). The rapid maladaptation of skeletal muscle to 14 days of mechanical unloading in middle-aged adults emphasizes the need for robust countermeasures to preserve muscle function in astronauts. PMID:26796754

  15. Contraception in Turkey.

    PubMed

    1967-01-01

    Population control and the use of contraceptives were discusses at the biannual meeting of the Turkish Academy of Medicine in September 1966. This was of special importance because contraception and dissemination of information about it were illegal in Turkey for many years before 1965. Thus, until quite recently Turkish doctors had only limited experience of modern contraceptive methods. Oral contraceptives and IUDs were discussed at the Academy meeting, and Dr Nusret Fisek has sent the Bulletin a summary of the main points raises. Oral contraceptives: Only minor side-effects were found and were ignored or easily treated; they disappeared when the oral contraception was stopped. Serious conditions such as liver dysfunction, thromboembolic phenomena, and diabetes have not been found. Intra-uterine devices: Endometritis requiring treatment is infrequent. In 23 of 45 women who had used IUDs for six months, endometrial histology showed diffuse bleeding, endometrial oedema or lymphocyctic endometritis. Expulsion and medical removal rates for IUDs over a six-month period were 5% in one clinic and 12% in another, with a pregnancy rate of between 1.2%. There was only one perforation in 6000 insertions. The doctor's attitude had a great influence on removal and discontinuation rates. In a large maternity hospital the Medical Board accepted, as a medical reason for induced abortion, accidental pregnancies that occurred in women wearing IUDs. PMID:12304991

  16. Maternal filicide in Turkey.

    PubMed

    Eke, Salih Murat; Basoglu, Saba; Bakar, Bulent; Oral, Gokhan

    2015-01-01

    Filicide occurs in every socioeconomic stratum around the world. This study was conducted to evaluate motives, psychopathological aspects, and socio-demographic factors of 74 filicide cases of women in Turkey. Mean age of mothers, most of whom committed infanticide, was 26 years, and breakdown of criminal offenses are as follows: "to get rid of unwanted babies" (24.3%), "acute psychotic-type filicide" (21.6%), "fatal child abuse and neglect" (17.6%), "to get revenge" (12.2%), "protect the lonely child from the harm and badness after suicide" (10.8%), and "pity" (9.5%) motives. Results showed that maternal filicide cannot be reduced to only mental instability or environmental factors and indicates deficiencies in the capacity of the mothers' role in connecting with their child and with parenting skills. Finally, with regard to defendants' motives, similar factors that contribute to committing maternal filicide should be considered while making an assessment of the data and determining employee risk groups. PMID:25066272

  17. Lecithin:Cholesterol Acyltransferase (LCAT) Deficiency Promotes Differentiation of Satellite Cells to Brown Adipocytes in a Cholesterol-dependent Manner.

    PubMed

    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. PMID:26494623

  18. Turkey vulture surveys in Cuba

    USGS Publications Warehouse

    Wotzkow, C.; Wiley, J.W.

    1988-01-01

    Turkey Vultures (Cathartes aura), were surveyed monthly in Cuba from March 1982-January 1983. A total of 25371 vultures were tallied in 7186 km (3.5 vultures/transect km) of roadside counting along main highways leading from the city of La Habana (northwestern Cuba) to the city of Las Tunas (southeast). Numbers of vultures counted declined substantially beyond 200 m from the transect road. Density of vultures observed within 200 m of the road along the transect route was 0.06/ha. Highest counts were obtained in March, April and June. Turkey Vulture flying activity was greatest during the periods 0900-1200 H and 1400-1700 H.

  19. β-Hydroxy-β-methylbutyrate (HMB) enhances the proliferation of satellite cells in fast muscles of aged rats during recovery from disuse atrophy.

    PubMed

    Alway, Stephen E; Pereira, Suzette L; Edens, Neile K; Hao, Yanlei; Bennett, Brian T

    2013-09-01

    Loss of myonuclei by apoptosis is thought to contribute to sarcopenia. We have previously shown, that the leucine metabolite, β-hydroxy-β-methylbutyrate (HMB) suppresses apoptotic signaling and the apoptotic index (the ratio of apoptotic positive to apoptotic negative myonuclei) during muscle disuse and during reloading periods after disuse in aged rats. However, it was not clear if the apoptotic signaling indexes were due only to preservation of myonuclei or if perhaps the total myogenic pool increased as a result of HMB-mediated satellite cell proliferation as this would have also reduced the apoptotic index. In this study, we tested the hypothesis that HMB would augment myogenic cells (satellite cells) proliferation during muscle recovery (growth) after a period of disuse in senescent animals. The hindlimb muscles of 34 month old Fisher 344 × Brown Norway rats were unloaded for 14 days by hindlimb suspension (HLS), and then reloaded for 14 days. The rats received either Ca-HMB (340 mg/kg body weight; n = 16), or the vehicle (n = 10) by gavage throughout the experimental period. HMB prevented the functional decline in maximal plantar flexion isometric force production during the reloading period, but not during HLS. HMB-treatment enhanced the proliferation of muscle stem cells as shown by a greater percentage of satellite cells that had proliferated (more BrdU positive, Pax-7 positive, and more Pax7/Ki67 positive nuclei) and as a result, more differentiated stem cells were present (more MyoD/myogenin positive myonuclei), relative to total myonuclei, in reloaded plantaris muscles as compared to reloaded muscles from vehicle-treated animals. Furthermore HMB increased the nuclear protein abundance of proliferation markers, inhibitor of differentiation-2 and cyclin A, as compared to vehicle treatment in reloaded muscles. Although HMB increased phosphorylated Akt during reloading, other mTOR related proteins were not altered by HMB treatment. These data show that

  20. Satellite Videoconferences

    NASA Technical Reports Server (NTRS)

    1990-01-01

    NASA is helping thousands of teachers to learn more about aerospace matters, improve their classroom skills, and expand significantly the content of their aerospace education curricula by means of live educational satellite videoconferences. The 1 1/2 hour 'Update for Teachers' programs originate at Oklahoma State University (OSU) Telecommunications Center. The television signals are transmitted to the WESTAR IV communications satellite, which remits them to participating schools across the U.S. and in parts of Mexico and Canada. The schools are equipped with small home style satellite reception dishes. Education Satellite Videoconference programs are conducted four times yearly, covering a variety of aerospace subjects. Teachers can call toll-free and have questions answered after the speaker's presentations. Information about NASA educational resources and how to obtain them will be provided.

  1. Satellite observations

    NASA Astrophysics Data System (ADS)

    1984-05-01

    In 1982 and 1983, six scientific satellites were operated successfully. Two of them, JIKIKEN and ISS-b, performed observations of the Earth's plasma environment. HINOTORI, the solar maximum satellite, observed a number of solar flares. HAKUCHO and newly launched TENMA conducted various observations of cosmic X-ray sources. HIMAWARI-2 is a meteorological satellite but its payload includes a solar particle monitor. EXOS-C was successfully launched in February, 1983, and participants in the MAP (Middle Atmosphere Program). Following these missions, the PLANET-A project comprising two missions, MS-T5 and PLANET-A, is under preparation for the participation in the international cooperative exploration of Comet P/Halley. The third X-ray astronomy satellite ASTRO-C is currently scheduled for 1987 launch.

  2. Satellite myths

    NASA Astrophysics Data System (ADS)

    Easton, Roger L.; Hall, David

    2008-01-01

    Richard Corfield's article “Sputnik's legacy” (October 2007 pp23-27) states that the satellite on board the US Vanguard rocket, which exploded during launch on 6 December 1957 two months after Sputnik's successful take-off, was “a hastily put together contraption of wires and circuitry designed only to send a radio signal back to Earth”. In fact, the Vanguard satellite was developed over a period of several years and put together carefully using the best techniques and equipment available at the time - such as transistors from Bell Laboratories/Western Electric. The satellite contained not one but two transmitters, in which the crystal-controlled oscillators had been designed to measure both the temperature of the satellite shell and of the internal package.

  3. Labour migration from Turkey.

    PubMed

    Uner, S

    1988-01-01

    This study is concerned with Turkish labor migration to Western Europe. Earlier and recent patterns of labor migration, characteristics of migrants by occupation, area of destination, and by geographical origins are discussed. Economic and demographic consequences of labor migration are also analyzed. It is estimated that Turkey's population will reach 73 million at the year 2000 with the present growth rate of 2.48% annually. Considering the efforts made to slow down the present high fertility rates and assuming that the decrease in labor force participation during 1970-1980 continues, the author concludes that the labor supply will increase with a growth rate of 2% annually for the next 13-15 years. Thus, the labor supply will reach 26.6 million people in the year 2000 from the 1980 level of 17.8 million. Assuming also that the income/employment elasticity of .25 which was observed throughout the period of 1960-1980 will not change until 2000, the annual growth rate of employment may be estimated as 1.5%. Thus, the number of people employed will reach 20 million in the year 1990 and 23.2 million in the year 2000. 8.8 million people will join the labor market as new entrants between 1980 and 2000. Only 6 million people out of 8.8 million will be employed. Thus, in the year 2000, it is estimated that 2.8 million new unemployed people will be added to the already open unemployment figure 1980 census data give the number of unemployed as .6 million people. Adding the 2.8 million new unemployed to this figure totals 3.4 million unemployed in 2000. The State Planning Organization's estimate of labor surplus for 1980 was 2.5 million people. When 2.8 million unemployed people are added to this figure, the labor surplus for the year 2000 reaches 5.3 million people. PMID:12342136

  4. Semaphorin 3A promotes activation of Pax7, Myf5, and MyoD through inhibition of emerin expression in activated satellite cells.

    PubMed

    Qahar, Mulan; Takuma, Yuko; Mizunoya, Wataru; Tatsumi, Ryuichi; Ikeuchi, Yoshihide; Nakamura, Mako

    2016-06-01

    We previously showed that Semaphorin 3A (Sema3A) expression was induced when quiescent muscle satellite cells were stimulated by hepatocyte growth factor and became activated satellite cells (ASCs). However, how Sema3A regulates genes in the early phase of ASCs remains unclear. In this study, we investigated whether Sema3A signaling can regulate the early phase of ASCs, an important satellite cell stage for postnatal growth, repair, and maintenance of skeletal muscle. We showed that expression of the myogenic proliferation regulatory factors Pax7 and Myf5 was decreased in myoblasts transfected with Sema3A siRNA. These cells failed to activate expression MyoD, another myogenic proliferation regulatory factor, during differentiation. Interestingly, some of the Sema3A-depleted cells did not express Pax7 and MyoD and had enlarged nuclei and very large cytoplasmic areas. We also observed that Pax7 and Myf5 expression was increased in Myc-Sema3A overexpressing myoblasts. BrdU analysis indicated that Sema3A regulated proliferation of ASCs. These findings suggest that Sema3A signaling can modulate expression of Pax7, Myf5, and MyoD. Moreover, we found that expression of emerin, an inner nuclear membrane protein, was regulated by Sema3A signaling. Emerin was identified by positional cloning as the gene responsible for the X-linked form of Emery-Dreifuss muscular dystrophy (X-EDMD). In conclusion, our results support a role for Sema3A in maintaining ASCs through regulation, via emerin, of Pax7, Myf5, and MyoD expression. PMID:27239431

  5. Alcohol fuel research in Turkey

    SciTech Connect

    Karaosmanoglu, F.; Isigiguer-Erguedenler, A.; Aksoy, H.A.

    1998-12-01

    Turkey, like most of the developing countries of the world, has vast agricultural potential, yet the country is highly dependent on oil imports, which satisfy 90% of its crude oil demand. Since Turkey had an economy based on agriculture, the usage of national resources in the energy field is extremely important. In the first years of the Turkish Republic, in 1931, the usage of national resources as an alternative to conventional fuels became a subject of increasing interest. Since then a lot of research has been conducted, but only a limited amount of application has been realized. Alcohol has always occupied an important place among the alternative fuel studies. The subject has been the scope of some research institute projects and university and government development planning studies. In Turkey, one of the most important studies in this area has been undertaken by the authors` research group in their university. This study is a general review of alcohol usage as an alternative automotive fuel in Turkey. This review includes a short history of the subject, the approach of the government, the research results, possible developments on the subject in the near future, and finally, it concludes with proposals.

  6. Early Childhood Inclusion in Turkey

    ERIC Educational Resources Information Center

    Diken, Ibrahim H.; Rakap, Salih; Diken, Ozlem; Tomris, Gozde; Celik, Secil

    2016-01-01

    Inclusion of young children with disabilities into regular preschool classrooms is a common practice that has been implemented for several decades in industrialized nations around the world, and many developing countries including Turkey have been developing and implementing laws, regulation, and services to support inclusion and teaching in…

  7. Small satellites

    NASA Technical Reports Server (NTRS)

    Thomas, P.; Veverka, J.; Dermott, S.

    1986-01-01

    Satellites smaller than Mimas (r = 195 km) are distinguished by irregular overall shapes and by rough limb topography. Material properties and impact cratering dominate the shaping of these objects. Long fragmentation histories can produce a variety of internal structures, but so far there is no direct evidence that any small satellite is an equilibrium ellipsoid made up of noncohesive gravitationally bound rubble. One many bodies that orbit close to their primary the tidal and rotational components of surface gravity strongly affect the directions of local g and thereby affect the redistribution of regolith by mass wasting. Downslope movement of regolith is extensive on Deimos, and is probably effective on many other small satellites. It is shown that in some cases observed patterns of downslope mass wasting cold produce useful constraints on the satellite's mean density. The diversity of features seen in the few high-resolution images of small satellites currently available suggests that these objects have undergone complex histories of cratering, fragmentation, and regolith evolution.

  8. Satellite broadcasting

    NASA Astrophysics Data System (ADS)

    Gregory, D.; Rainger, P.; Harvey, R. V.; Jennings, A.

    Questions related to direct broadcasting satellites are addressed with attention given to celestial mechanics, synchronous orbits, propagation, international plans, domestic installation, related laws and system costs. The role of the World Administrative Planning Conference (WARC) organization is discussed and contrasted with that of the regional administrative radio conference. Topics related to the field of law include coverage and overspill, regulation and control, copyrights and international organizations. Alternative ways of estimating direct broadcasting system costs are presented with consideration given to satellite costs as a function of mass, launch costs and system costs as a function of power.

  9. Some background about satellites

    NASA Technical Reports Server (NTRS)

    Burns, Joseph A.

    1986-01-01

    Four tables of planetary and satellite data are presented which list satellite discoveries, planetary parameters, satellite orbits, and satellite physical properties respectively. A scheme for classifying the satellites is provided and it is noted that most known moons fall into three general classes: regular satellites, collisional shards, and irregular satellites. Satellite processes are outlined with attention given to origins, dynamical and thermal evolution, surface processes, and composition and cratering. Background material is provided for each family of satellites.

  10. Diminished satellite cells and elevated adipogenic gene expression in muscle as caused by ovariectomy are averted by low-magnitude mechanical signals.

    PubMed

    Frechette, Danielle M; Krishnamoorthy, Divya; Adler, Benjamin J; Chan, M Ete; Rubin, Clinton T

    2015-07-01

    Age-related degeneration of the musculoskeletal system, accelerated by menopause, is further complicated by increased systemic and muscular adiposity. The purpose of this study was to identify at the molecular, cellular, and tissue levels the impact of ovariectomy on adiposity and satellite cell populations in mice and whether mechanical signals could influence any outcomes. Eight-week-old C57BL/6 mice were ovariectomized, with one half subjected to low-intensity vibration (LIV; 0.3 g/90 Hz, 15 min/day, 5 day/wk; n = 10) for 6 wk and the others sham vibrated (OVX; n = 10). Data are compared with age-matched, intact controls (AC; n = 10). In vivo μCT analysis showed that OVX mice gained 43% total (P < 0.001) and 125% visceral adiposity (P < 0.001) compared with their baseline after 6 wk, whereas LIV gained only 21% total (P = 0.01) and 70% visceral adiposity (P < 0.01). Relative to AC, expression of adipogenic genes (PPARγ, FABP4, PPARδ, and FoxO1) was upregulated in OVX muscle (P < 0.05), whereas LIV reduced these levels (P < 0.05). Adipogenic gene expression was inversely related to the percentage of total and reserve satellite cell populations in the muscle, with both declining in OVX compared with AC (-21 and -28%, respectively, P < 0.01). LIV mitigated these declines (-11 and -17%, respectively). These results provide further evidence of the negative consequences of estrogen depletion and demonstrate that mechanical signals have the potential to interrupt subsequent adipogenic gene expression and satellite cell suppression, emphasizing the importance of physical signals in protecting musculoskeletal integrity and slowing the fat phenotype. PMID:25930028

  11. 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.

    PubMed

    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. PMID:24168791

  12. Diminished satellite cells and elevated adipogenic gene expression in muscle as caused by ovariectomy are averted by low-magnitude mechanical signals

    PubMed Central

    Frechette, Danielle M.; Krishnamoorthy, Divya; Adler, Benjamin J.; Chan, M. Ete

    2015-01-01

    Age-related degeneration of the musculoskeletal system, accelerated by menopause, is further complicated by increased systemic and muscular adiposity. The purpose of this study was to identify at the molecular, cellular, and tissue levels the impact of ovariectomy on adiposity and satellite cell populations in mice and whether mechanical signals could influence any outcomes. Eight-week-old C57BL/6 mice were ovariectomized, with one half subjected to low-intensity vibration (LIV; 0.3 g/90 Hz, 15 min/day, 5 day/wk; n = 10) for 6 wk and the others sham vibrated (OVX; n = 10). Data are compared with age-matched, intact controls (AC; n = 10). In vivo μCT analysis showed that OVX mice gained 43% total (P < 0.001) and 125% visceral adiposity (P < 0.001) compared with their baseline after 6 wk, whereas LIV gained only 21% total (P = 0.01) and 70% visceral adiposity (P < 0.01). Relative to AC, expression of adipogenic genes (PPARγ, FABP4, PPARδ, and FoxO1) was upregulated in OVX muscle (P < 0.05), whereas LIV reduced these levels (P < 0.05). Adipogenic gene expression was inversely related to the percentage of total and reserve satellite cell populations in the muscle, with both declining in OVX compared with AC (−21 and −28%, respectively, P < 0.01). LIV mitigated these declines (−11 and −17%, respectively). These results provide further evidence of the negative consequences of estrogen depletion and demonstrate that mechanical signals have the potential to interrupt subsequent adipogenic gene expression and satellite cell suppression, emphasizing the importance of physical signals in protecting musculoskeletal integrity and slowing the fat phenotype. PMID:25930028

  13. Satellite description

    NASA Astrophysics Data System (ADS)

    Gillett, F. C.; Clegg, P. E.; Neugebauer, G.; Langford, D.; Pouw, A.; Irace, W.; Houck, J.

    The onboard computers and their associated software, the attitude control system, and data recording and the communication links of the infrared astronomy satellite (TRAS) are discussed. The IRAS telescope system is considered in detail. Attention is directed towards the cryogenics, thermal control, optics, focal plane assembly, and electronics associated with the telescope system.

  14. 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

    NASA Technical Reports Server (NTRS)

    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.

  15. Susceptibility of convalescent turkeys to pulmonary aspergillosis.

    PubMed

    Kunkle, R A; Sacco, R E

    1998-01-01

    Pulmonary lesions resulting from Aspergillus fumigatus inoculation were assessed in convalescent turkeys and compared with those in previously noninoculated (control) turkeys. In addition, lesions observed in small Beltsville white (SBW) turkeys were compared with those in broad-breasted white (BBW) turkeys challenged with the same inoculum. Turkeys were challenged by unilateral posterior thoracic air sac (PTAS) inoculation, rechallenged via the contralateral air sac after 5 wk, and then necropsied 1 wk later. Pulmonary lesions induced by the initial challenge had resolved in 6 of 10 SBW and 9 of 10 BBW turkeys. However, convalescence did not protect against pulmonary aspergillosis subsequent to rechallenge; 10 of 10 SBW and 9 of 10 BBW developed granulomatous pulmonary lesions on the side of reexposure. A greater proportion of control SBW turkeys developed pneumonia and airsacculitis following challenge as compared with the BBW breed. Lesions were limited to the lower respiratory tract in all turkeys and were confined to the ipsilateral lung and PTAS in the singly inoculated control turkeys. This study demonstrates that convalescence from pulmonary aspergillosis does not confer protection against rechallenge but may, instead, decrease resistance to subsequent infection. PMID:9876849

  16. 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.

    PubMed

    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. PMID:27454226

  17. Considerations for NATO satellite communications in the post-2000 era

    NASA Astrophysics Data System (ADS)

    Ince, A. Nejat

    1993-02-01

    The National Delegates Board of AGARD, upon recommendation by the Avionics Panel of AGARD, approved in March 1986 the establishment of WG-13 to study satellite communications for NATO under the direction of Prof. Dr. Nejat Ince of Turkey. Some 14 scientists/engineers, from research and industrial establishments of Canada, France, the Federal Republic of Germany, Norway, Turkey, the United Kingdom, the United States of America as well as from International Military Staff of NATO and SHAPE Technical Centre, participated in the work of WG-13. This paper is a brief summary of the studies carried out by the group in the period 1988-1990 on the type of satellite communication systems which NATO can have in the post-2000 era including the critical techniques and technologies that need to be developed for this purpose.

  18. Serotonin Localization in the Turkey Vaginal but not Sperm Storage Tubule Epithelia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our knowledge regarding the mechanism of sperm selection and transport in the hen’s vagina is meager. Preliminary observations indicate the presence of non-neuron endocrine cells in the epithelia lining the lumina of the turkey hen vagina and uterovaginal junction. While no cells in the vagina or U...

  19. Virtual Satellite

    NASA Technical Reports Server (NTRS)

    Hammrs, Stephan R.

    2008-01-01

    Virtual Satellite (VirtualSat) is a computer program that creates an environment that facilitates the development, verification, and validation of flight software for a single spacecraft or for multiple spacecraft flying in formation. In this environment, enhanced functionality and autonomy of navigation, guidance, and control systems of a spacecraft are provided by a virtual satellite that is, a computational model that simulates the dynamic behavior of the spacecraft. Within this environment, it is possible to execute any associated software, the development of which could benefit from knowledge of, and possible interaction (typically, exchange of data) with, the virtual satellite. Examples of associated software include programs for simulating spacecraft power and thermal- management systems. This environment is independent of the flight hardware that will eventually host the flight software, making it possible to develop the software simultaneously with, or even before, the hardware is delivered. Optionally, by use of interfaces included in VirtualSat, hardware can be used instead of simulated. The flight software, coded in the C or C++ programming language, is compilable and loadable into VirtualSat without any special modifications. Thus, VirtualSat can serve as a relatively inexpensive software test-bed for development test, integration, and post-launch maintenance of spacecraft flight software.

  20. INTESTINAL FLORA OF WILD AND DOMESTIC TURKEYS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    GOAL: To describe and compare the intestinal bacterial communities of domestic and wild turkeys. METHODS: Ceca from five domestic turkeys killed on-farm (Farm A) and eight from the abattoir (five from Farm A, three from Farm B) were examined for bacterial composition. Ceca from wild birds were p...

  1. Rights of the Child in Turkey.

    ERIC Educational Resources Information Center

    Naqvi, Yasmin

    This report to the United Nations Convention on the Rights of the Child contains observations of the World Organisation Against Torture (OMCT) concerning the application of the Convention by Turkey and observations regarding violence against girls in Turkey. The report is presented in three major parts. Part 1 asserts that despite the considerable…

  2. Extreme Forms of Child Labour in Turkey

    ERIC Educational Resources Information Center

    Degirmencioglu, Serdar M.; Acar, Hakan; Acar, Yuksel Baykara

    2008-01-01

    Two little known forms of child labour in Turkey are examined. The process through which these children are made to work has parallels with the experiences of slaves. First, a long-standing practice from Northwestern Turkey of parents hiring children to better-off farmers is examined. Further, a more recent problem is examined where children are…

  3. Principals' Openness to Change in Malatya, Turkey

    ERIC Educational Resources Information Center

    Aslan, Mahire; Beycioglu, Kadir; Konan, Necdet

    2008-01-01

    When change is deemed necessary, principals' attitudes towards changes are significant for successful restructuring of schools. This study aimed to ascertain the extent to which principals in Malatya, Turkey, are open to change. A questionnaire was administered to 156 elementary and secondary school principals in Malatya, Turkey. This…

  4. Characteristics of Inclusive Classrooms in Turkey

    ERIC Educational Resources Information Center

    Melekoglu, Macid Ayhan

    2014-01-01

    In this paper, inclusive classrooms in Turkey are described in terms of the characteristics of both classroom teachers and students with special needs. Participants of this study consisted of 54 teachers working in inclusive classrooms and 54 students with mild intellectual disabilities in those classrooms in Turkey. Data for this study were…

  5. Citizenship Education in Turkey: Inclusive or Exclusive

    ERIC Educational Resources Information Center

    Ince, Basak

    2012-01-01

    This paper scrutinises citizenship education in Turkey from the foundation of the Turkish Republic (1923) to the present and explores the extent to which it encourages inclusive or exclusive concepts of national identity and citizenship. In Turkey, where there are citizens belonging to ethnic and religious minorities, civic education plays a…

  6. Enteric parvovirus infections of chickens and turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chicken and turkey parvoviruses are members of the Parvovirus family. Comparative sequence analysis of their genome structure revealed that they should form a new genus within the vertebrate Parvovirinae subfamily. The first chicken and turkey parvoviruses were identified by electron microscopy duri...

  7. Government Publications and Gray Literature in Turkey

    ERIC Educational Resources Information Center

    Anameric, Hakan

    2009-01-01

    This paper investigates bibliographic control of government publications and gray literature in Turkey, in order to determine what further measures are needed to support researchers in both Turkey and abroad. It reports the circumstances surrounding the creation of "The Bibliography of Government Publications" prepared in 1971, and outlines how…

  8. Timation 3 satellite. [artificial satellite for navigation, space radiation, and time transfer applications

    NASA Technical Reports Server (NTRS)

    Bartholomew, C. A.

    1972-01-01

    The characteristics of the Timation 3 satellite are discussed. A diagram of the basic structure is provide to show the solar panels, navigation and telemetry antennas, gravity gradient booms, and solar cell experiments. The specific application of the satellite for time management or time transfer for navigation purposes is reported. Various measurements and experiments conducted by the satellite are described.

  9. Wild Edible Mushrooms from Turkey as Possible Anticancer Agents on HepG2 Cells Together with Their Antioxidant and Antimicrobial Properties.

    PubMed

    Sadi, Gokhan; Kaya, Abdullah; Yalcin, Hicret Asli; Emsen, Bugrahan; Kocabas, Aytac; Kartal, Deniz Irtem; Altay, Ahmet

    2016-01-01

    This study was designed to reveal cell growth inhibitory potential of six different edible mushrooms: Ramaria flava, Agrocybe molesta, Volvopluteus gloiocephalus, Lactarius deliciosus, Bovista plumbea, and Tricholoma terreum on HepG2 cells together with their antioxidant and antibacterial power. Methanolic extracts of V gloiocephalus and aqueous extracts of R. flava had the most potential cytotoxic effects over HepG2 cells. The best results for 2,2-diphenyl-1-picrylhydrazyl radical scavenging activities were obtained from both aqueous and methanolic extracts of R. flava. Methanolic extracts of T. terreum (IC50 = 1.62 mg/mL) and aqueous extracts of B. plumbea (IC50 = 0.49 mg/mL) showed maximum metal chelating activity. The highest reducing capacities were observed among the methanolic extracts of R. flava (EC50 = 1.65 mg/mL) and aqueous extracts of B. plumbea (EC50 = 1.71 mg/ mL). High-performance liquid chromatography analysis revealed the presence of many phenolic compounds in macrofungi; gallic acid and p-coumaric acid were the two main phenolics identified in all extracts. Antibacterial studies indicated that all six tested mushrooms showed antibacterial activity on at least three microorganisms. These results indicate that different extracts of the investigated mushrooms have considerable cytotoxic, antioxidant, and antibacterial properties and may be utilized as a promising source of therapeutics. PMID:27279448

  10. Astronomical site selection for Turkey using GIS techniques

    NASA Astrophysics Data System (ADS)

    Aksaker, N.; Yerli, S. K.; Erdoğan, M. A.; Erdi, E.; Kaba, K.; Ak, T.; Aslan, Z.; Bakış, V.; Demircan, O.; Evren, S.; Keskin, V.; Küçük, İ.; Özdemir, T.; Özışık, T.; Selam, S. O.

    2015-10-01

    A site selection of potential observatory locations in Turkey have been carried out by using Multi-Criteria Decision Analysis (MCDA) coupled with Geographical Information Systems (GIS) and satellite imagery which in turn reduced cost and time and increased the accuracy of the final outcome. The layers of cloud cover, digital elevation model, artificial lights, precipitable water vapor, aerosol optical thickness and wind speed were studied in the GIS system. In conclusion of MCDA, the most suitable regions were found to be located in a strip crossing from southwest to northeast including also a diverted region in southeast of Turkey. These regions are thus our prime candidate locations for future on-site testing. In addition to this major outcome, this study has also been applied to locations of major observatories sites. Since no goal is set for the best, the results of this study is limited with a list of positions. Therefore, the list has to be further confirmed with on-site tests. A national funding has been awarded to produce a prototype of an on-site test unit (to measure both astronomical and meteorological parameters) which might be used in this list of locations.

  11. Role of the mTORC1 Complex in Satellite Cell Activation by RNA-Induced Mitochondrial Restoration: Dual Control of Cyclin D1 through MicroRNAs

    PubMed Central

    Jash, Sukanta; Dhar, Gunjan; Ghosh, Utpalendu

    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-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. PMID:25047835

  12. Degenerative primer design and gene sequencing validation for select turkey genes.

    PubMed

    Hutsko, Stephanie L; Lilburn, Michael S; Wick, Macdonald

    2016-06-01

    We successfully designed and validated degenerative primers for turkey genes MUC2, RPS13, TBP and TFF2 based on chicken sequences in order to use gene transcription analysis to evaluate (quantify) the mucin transcription to probiotic supplementation in turkeys. Primers were designed for the genes MUC2, TFF2, RPS13 and TBP using a degenerative primer design method based on the available Gallus gallus sequences. All primer sets, which produced a single PCR amplicon of the expected sizes, were cloned into the TOPO(®) vector and then transformed into TOP 10(®) competent cells. Plasmid DNA isolation was performed on the TOP10(®) cell culture and sent for sequencing. Sequences were analyzed using NCBI BLAST. All genes sequenced had over 90% homology with both the chicken and predicted turkey sequences. The sequences were used to design new 100% homologous primer sets for the genes of interest. PMID:27053625

  13. Activation of P2X7 receptors in glial satellite cells reduces pain through downregulation of P2X3 receptors in nociceptive neurons

    PubMed Central

    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 root ganglia tonically inhibit the expression of P2X3Rs in neurons. Reducing P2X7R expression using siRNA or blocking P2X7R activity by antagonists elicits P2X3R up-regulation, increases the activity of sensory neurons responding to painful stimuli, and evokes abnormal nociceptive behaviors in rats. Thus, contrary to the notion that P2X7R activation is cytotoxic, P2X7Rs in satellite cells play a crucial role in maintaining proper P2X3R expression in dorsal root ganglia. Studying the mechanism underlying the P2X7R–P2X3R control, we demonstrate that activation of P2X7Rs evokes ATP release from satellite cells. ATP in turn stimulates P2Y1 receptors in neurons. P2Y1 receptor activation appears to be necessary and sufficient for the inhibitory control of P2X3R expression. We further determine the roles of the P2X7R–P2Y1–P2X3R inhibitory control under injurious conditions. Activation of the inhibitory control effectively prevents the development of allodynia and increases the potency of systemically administered P2X7R agonists in inflamed rats. Thus, direct blocking P2X7Rs, as proposed before, may not be the best strategy for reducing pain or lessening neuronal degeneration because it also disrupts the protective function of P2X7Rs. PMID:18946042

  14. [The urbanization rate in Turkey].

    PubMed

    Widy-kwiatkowska, J

    1994-01-01

    Data from the annual statistical report on Turkey for 1990 and the results of research from 1985 and 1990 were utilized and compared with the trends of urbanization observed in the 1969 work of Z. Siemek on Turkey. In 1990, Turkey had about 56.5 million people with an average annual natural growth rate of 2.6% and an unemployment rate of 16%. The rural population made up 41% of the total populace. Urbanization was on the increase, from 47% in 1980, to 55% in 1985, and 59% in 1990. Urbanization in Ankara, because of its location in the center of Turkey, was particularly active in the regions of Anatolia, although it was still isolated in terms of intensified development. Istanbul's The population of Istanbul numbered 6,754,000 people in 1990. It is the major industrial center of the country with about 20% of industrial plants and 17% of the work force in the manufacturing industry. The largest degree of urbanization was demonstrated by Ankara: in 1927 its population numbered only 74,500 people, in 1965 about 902,000 inhabitants, and in 1990 about 2,837,000 people. During the period 1985-90, only 2 out of 73 provinces experienced a decline of the urban population: Kirikkale from 70.4% to 69.7% (because of the dynamic development of the Central region) and Istanbul from 95.4% to 92.4%. During this same period, Kirikkale's urban population, compared with the nation's total urban population, also declined from 0.9% to 0.7% because of immigration of both urban and rural people to other, more attractive provinces. The growth of urban population in the province of Istanbul varied from 1% to 10% during the period and made up 20.3% of the entire urban population. The Central region underwent a large degree of urbanization characterized by industrial-agricultural development. The city of Sivas became a center of communication. In the Central and Kurd regions, urbanization proceeded fast owing to the development of the Black Sea region and the immigration of Kurds from Iraq

  15. Survival after cryogenic freezing of Campylobacter species in ground Turkey patties treated with polyphosphates.

    PubMed

    Gunther Iv, Nereus W; Rajkowski, Kathleen T; Sommers, Christopher

    2015-02-01

    The use of polyphosphate-based marinades in the processing of poultry has been previously shown to increase the survival of Campylobacter species present in the exudates derived from these products. This study investigates the effects that some of the same polyphosphates have on the survival of Campylobacter species within a ground turkey product subjected to cryogenic freezing. Ground turkey patties with two different polyphosphate formulations added in two different concentrations were artificially contaminated with known concentrations of Campylobacter jejuni or Campylobacter coli. The patties were cryogenically frozen at -80°F (-62.2°C) with liquid nitrogen vapor and held at -20°C for 7 or 33 days, after which the number of Campylobacter surviving in the patties was determined. On average the cryogenic freezing resulted in a 2.5-log decrease in the survival of C. jejuni cells and a 2.9-log decrease in C. coli cells present in the turkey patties. Additionally, the presence of polyphosphates in the turkey patties had no effect on Campylobacter survival up to the maximum allowed concentration (0.5%) for polyphosphates in poultry marinades. Finally, it was determined that the added polyphosphates had little effect on the pH of the ground turkey meat; an effect which previously had been implicated in the enhancement of Campylobacter survival due to the presence of polyphosphates. PMID:25710161

  16. Solar power satellite

    SciTech Connect

    Copeland, R.J.; Martin, J.D.

    1983-11-15

    A solar power satellite includes a truss structure having a plurality of independently controlled solar power modules mounted to one face of the truss structure. The solar power satellite is constructed in orbit by first forming and then assemblying component beam members to the truss structure. The solar power modules are constructed on a fabrication and assembly station movably attached to the truss structure and are then attached to the truss structure. The solar power modules include a primary reflector having a substantially parabolic curvature in cross section. A collector-radiator is mounted on the primary axis of the primary reflector. The cross-sectional configuration of the collector-radiator approximates a flattened inverted S-shape whereon the radius of curvature decreases as the curve approaches both its center and its end furthermost from the primary reflector. The primary reflector is contoured to reflect sun light onto the collector-radiator structure. The collector-radiator structure includes a plurality of spaced radiant energy converting cells. A plurality of light reflective fins are positioned between the converter cells. Each fin is thermally and electrically connected to converter cells on each side thereof. The fins provide radiant cooling of and series electrical connection between the converter cells. The fins also serve as a secondary reflector for concentrating sun light from the primary reflector onto the converter cells.

  17. Satellite Bioclimatology.

    NASA Astrophysics Data System (ADS)

    Goward, Samuel N.

    1989-07-01

    Satellite-acquired, remotely sensed observations of the earth's land areas are substatially advancing knowledge of global vegetation patterns. Recognition that combined visible/near infrared spectral reflectance observations are a general indicator of the presence, condition and magnitude of vegetation foliage provides a basis for explanation. This information is of considerable value in climatic research because of the links between climate variables and vegetation foliage. Presence of vegetation foliage is predominantly determined by a combination of local beat and moisture conditions. In turn, foliar presence determines local rates of photosynthesis, affects surface albedo, and influences local rates of evapotranspiration as well as other elements of surface energy/mass balance. Availability of these remotely sensed data provides, for the first time, a consistent, global means to directly study interactions between climate and vegetation. This understanding is now being incorporated in climatological research and should improve understanding of macroscale bioclimatology. Remote sensing technology and understanding of this technology are continuing to develop rapidly and further major advances in this new field of `satellite bioclimatology' can be expected in the near future.

  18. Meteorological satellites

    NASA Astrophysics Data System (ADS)

    1981-10-01

    Meteor-2 (second generation meteorological satellite) and an experimental satellite on which instruments are being tested and modified for the requirements of hydrometeorology and a determination of natural resources are presently operational in the U.S.S.R. Television devices with a 1-10 km terrain image resolution operating in the visible and infrared region are used to determine the space system, velocity and direction of cloud movements and provide information about the snow and ice cover, cyclones, storms, vortices in the atmosphere, and velocity and direction of wind. Images with a 50-1000 m resolution make possible geological and hydrological surveys, an evaluation of the state of vegetation and crops, detection of forest fires, determination of pollution of the atmosphere and sea and determination of optimal fishing regions in the ocean. Measurement of the intensity of atmospheric radiation in narrow infrared regions and very high frequencies allows remote evaluation of the temperature and humidity distribution in the vertical cross section of the Earth's atmosphere.

  19. The determination of the most applicable PWV model for Turkey

    NASA Astrophysics Data System (ADS)

    Deniz, Ilke; Gurbuz, Gokhan; Mekik, Cetin

    2016-07-01

    Water vapor is a key component for modelling atmosphere and climate studies. Moreover, long-term water vapor changes can be an independent source for detecting climate changes. Since Global Navigation Satellite Systems (GNSS) use microwaves passing through the atmosphere, atmospheric effects are modeled with high accuracy. Tropospheric effects on GNSS signals are estimated with total zenith delay parameter (ZTD) which is the sum of hydrostatic (ZHD) and wet zenith delay (ZWD). The first component can be obtained from meteorological observations with high accuracy; the second component, however, can be computed by subtracting ZHD from ZTD (ZWD=ZTD-ZHD). Afterwards, the weighted mean temperature (Tm) or the conversion factor (Q) is used for the conversion between the precipitable water vapor (PWV) and ZWD. The parameters Tm and Q are derived from the analysis of radiosonde stations' profile observations. Numerous Q and Tm models have been developed for each radiosonde station, radiosonde station group, countries and global fields such as Bevis Tm model and Emardson and Derks' Q models. So, PWV models (Tm and Q models) applied for Turkey have been developed using a year of radiosonde data (2011) from 8 radiosonde stations. In this study the models developed are tested by comparing PWVGNSS computed applying Tm and Q models to the ZTD estimates derived by Bernese and GAMIT/GLOBK software at GNSS stations established at Istanbul and Ankara with those from the collocated radiosonde stations (PWVRS) from October 2013 to December 2014 with the data obtained from a project (no 112Y350) supported by the Scientific and Technological Research Council of Turkey (TUBITAK). The comparison results show that PWVGNSS and PWVRS are in high correlation (86 % for Ankara and 90% for Istanbul). Thus, the most applicable model for Turkey and the accuracy of GNSS meteorology are investigated. In addition, Tm model was applied to the ZTD estimates of 20 TUSAGA-Active (CORS-TR) stations in

  20. Reduction of exposure to blood donors in preterm infants submitted to red blood cell transfusions using pediatric satellite packs

    PubMed Central

    Uezima, Cristina Lika; Barreto, Ariane Moreira; Guinsburg, Ruth; Chiba, Akemi Kuroda; Bordin, José Orlando; Barros, Melca Maria O.; dos Santos, Amélia Miyashiro N.

    2013-01-01

    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. PMID:24142309

  1. [Current malaria situation in Turkey].

    PubMed

    Gockchinar, T; Kalipsi, S

    2001-01-01

    Geographically, Turkey is situated in an area where malaria is very risky. The climatic conditions in the region are suitable for the malaria vector to proliferate. Due to agricultural infrastructural changes, GAP and other similar projects, insufficient environmental conditions, urbanization, national and international population moves, are a key to manage malaria control activities. It is estimated that malaria will be a potential danger for Turkey in the forthcoming years. The disease is located largely in south-eastern Anatolia. The Diyarbakir, Batman, Sanliurfa, Siirt, and Mardin districts are the most affected areas. In western districts, like Aydin and Manisa, an increase in the number of indigenous cases can be observed from time to time. This is due to workers moving from malaria districts to western parts to final work. Since these workers cannot be controlled, the population living in these regions get infected from indigenous cases. There were 84,345 malaria cases in 1994 and 82,096 in 1995, they decreased to 60,884 in 1996 and numbered 35,456 in 1997. They accounted for 36,842 and 20,963 in 1998 and 1999, respectively. In Turkey there are almost all cases of P. vivax malaria. There are also P. vivax and P. falciparum malaria cases coming from other countries: There were 321 P. vivax cases, including 2 P. falciparum ones, arriving to Turkey from Iraq in 1995. The P. vivax malaria cases accounted for 229 in 1996, and 67, cases P. vivax including 12 P. falciparum cases, in 1997, and 4 P. vivax cases in 1998 that came from that country. One P. vivax case entered Turkey from Georgia in 1998. The cause of higher incidence of P. vivax cases in 1995, it decreasing in 1999, is the lack of border controls over workers coming to Turkey. The other internationally imported cases are from Syria, Sudan, Pakistan, Afghanistan, Nigeria, India, Azerbaijan, Malaysia, Ghana, Indonesia, Yemen. Our examinations have shown that none of these internationally imported cases

  2. Radiological maps for Trabzon, Turkey.

    PubMed

    Kurnaz, A; Kucukomeroglu, B; Damla, N; Cevik, U

    2011-04-01

    The activity concentrations and absorbed gamma dose rates due to primordial radionuclides and (137)Cs have been ascertained in 222 soil samples in 18 counties of the Trabzon province of Turkey using a HPGe detector. The mean activity concentrations of (238)U, (232)Th, (40)K and (137)Cs in soil samples were 41, 35, 437 and 21 Bq kg(-1), respectively. Based on the measured concentrations of these radionuclides, the mean absorbed gamma dose in air was calculated as 59 nGy h(-1) and hence, the mean annual effective dose due to terrestrial gamma radiation was calculated as 72 μSv y(-1). In addition, outdoor in situ gamma dose rate (D) measurements were performed in the same 222 locations using a portable NaI detector and the annual effective dose was calculated to be 66 μSv y(-1) from these results. The results presented in this study are compared with other parts of Turkey. Radiological maps of the Trabzon province were composed using the results obtained from the study. PMID:21382657

  3. Understanding Urban Regeneration in Turkey

    NASA Astrophysics Data System (ADS)

    Candas, E.; Flacke, J.; Yomralioglu, T.

    2016-06-01

    In Turkey, rapid population growth, informal settlements, and buildings and infrastructures vulnerable to natural hazards are seen as the most important problems of cities. Particularly disaster risk cannot be disregarded, as large parts of various cities are facing risks from earthquakes, floods and landslides and have experienced loss of lives in the recent past. Urban regeneration is an important planning tool implemented by local and central governments in order to reduce to disaster risk and to design livable environments for the citizens. The Law on the Regeneration of Areas under Disaster Risk, commonly known as the Urban Regeneration Law, was enacted in 2012 (Law No.6306, May 2012). The regulation on Implementation of Law No. 6306 explains the fundamental steps of the urban regeneration process. The relevant institutions furnished with various authorities such as expropriation, confiscation and changing the type and place of your property which makes urban regeneration projects very important in terms of property rights. Therefore, urban regeneration projects have to be transparent, comprehensible and acceptable for all actors in the projects. In order to understand the urban regeneration process, the legislation and projects of different municipalities in Istanbul have been analyzed. While some steps of it are spatial data demanding, others relate to land values. In this paper an overview of the urban regeneration history and activities in Turkey is given. Fundamental steps of the urban regeneration process are defined, and particularly spatial-data demanding steps are identified.

  4. Survival of Clostridium perfringens During Baking and Holding of Turkey Stuffing1

    PubMed Central

    Woodburn, Margy; Kim, Chung H.

    1966-01-01

    Vegetative cells of three strains of Clostridium perfringens were used as inoculum for bread and onion stuffing for eight lightweight and eight heavyweight turkeys. When stuffed turkeys were refrigerated (5 ± 1 C for 24 ± 2 hr), a mean count of 580 vegetative cells of C. perfringens per gram of stuffing was reduced to undetectable levels (<6 per gram) in six of the eight. An inoculum of spores of the three strains used in a second series survived refrigerated holding with no change in numbers. During cooking of the stuffed turkeys in an oven at 94 C, numbers of vegetative cells fell steadily and numbers of spores remained constant or increased slightly (2 of 16 stuffings), until the temperature of the stuffing rose above that permitting growth. Viable C. perfringens cells were recovered from the stuffings at the end of cooking plus 1 hr for the group inoculated with the spore suspension. Storage of these stuffings resulted in marked reductions in numbers after 6 days at 5 ± 1 C and in increases after 24 ± 2 hr at 23 ± 1 C. Cells of a strain which produces spores not considered heat-resistant survived in stuffing in birds cooked to doneness in ovens at 94, 163, and 232 C. In accepted methods of cooking stuffed turkeys, C. perfringens contaminants may survive and create a hazard if subsequent storage is in a temperature range which permits their multiplication. PMID:16349696

  5. Satellite altimetry

    NASA Technical Reports Server (NTRS)

    Cheney, Robert E.

    1992-01-01

    Since altimetry data are not really old enough to use the term data archaeology, Mr. Cheney referred to the stewardship of these data. He noted that it is very important to document the basis for an altimetry data set as the algorithms and corrections used to arrive at the Geophysical Data Record (GDR) have been improving and are continuing to improve the precision of sea level data derived from altimetry. He noted that the GEOSAT Exact Repeat Mission (ERM) data set has recently been reprocessed by his organization in the National Ocean Service of NOAA and made available to the scientific community on CD/ROM disks by the National Oceanographic Data Center of the U.S. (NODC). The new data set contains a satellite orbit more precise by an order of magnitude together with an improved water vapor correction. A new, comprehensive GDR Handbook has also been prepared.

  6. The mammalian target of rapamycin signaling pathway regulates myocyte enhancer factor-2C phosphorylation levels through integrin-linked kinase in goat skeletal muscle satellite cells.

    PubMed

    Wu, Haiqing; Ren, Yu; Pan, Wei; Dong, Zhenguo; Cang, Ming; Liu, Dongjun

    2015-11-01

    Mammalian target of rapamycin (mTOR) signaling pathway plays a key role in muscle development and is involved in multiple intracellular signaling pathways. Myocyte enhancer factor-2 (MEF2) regulates muscle cell proliferation and differentiation. However, how the mTOR signaling pathway regulates MEF2 activity remains unclear. We isolated goat skeletal muscle satellite cells (gSSCs) as model cells to explore mTOR signaling pathway regulation of MEF2C. We inhibited mTOR activity in gSSCs with PP242 and found that MEF2C phosphorylation was decreased and that muscle creatine kinase (MCK) expression was suppressed. Subsequently, we detected integrin-linked kinase (ILK) using MEF2C coimmunoprecipitation; ILK and MEF2C were colocalized in the gSSCs. We found that inhibiting mTOR activity increased ILK phosphorylation levels and that inhibiting ILK activity with Cpd 22 and knocking down ILK with small interfering RNA increased MEF2C phosphorylation and MCK expression. In the presence of Cpd 22, mTOR activity inhibition did not affect MEF2C phosphorylation. Moreover, ILK dephosphorylated MEF2C in vitro. These results suggest that the mTOR signaling pathway regulates MEF2C positively and regulates ILK negatively and that ILK regulates MEF2C negatively. It appears that the mTOR signaling pathway regulates MEF2C through ILK, further regulating the expression of muscle-related genes in gSSCs. PMID:26041412

  7. Satellites in Education.

    ERIC Educational Resources Information Center

    Jones, David

    1988-01-01

    Describes the methods and materials used to obtain satellite pictures from weather satellites. Discusses possible physics lessons which can be done using this equipment including orbital mechanics, and how the satellite works. (CW)

  8. Identification of miR-2400 gene as a novel regulator in skeletal muscle satellite cells proliferation by targeting MYOG gene

    SciTech Connect

    Zhang, Wei Wei; Tong, Hui Li; Sun, Xiao Feng; Hu, Qian; Yang, Yu; Li, Shu Feng; Yan, Yun Qin; Li, Guang Peng

    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.

  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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  10. The pathogenicity of avian metapneumovirus subtype C wild bird isolates in domestic turkeys

    PubMed Central

    2013-01-01

    Background Avian metapneumovirus subtype C (aMPV/C) causes severe upper respiratory disease in turkeys. Previous report revealed the presence of aMPV/C in wild birds in the southeast regions of the U.S. Methods In this study, aMPV/C positive oral swabs from American coots (AC) and Canada geese (CG) were passaged three times in the respiratory tract of specific pathogen free (SPF) turkeys and used as aMPV/C P3 virus isolates in subsequent studies. Results Wild bird P3 isolates showed similar growth characteristics when compared to virulent aMPV/C in chicken embryo fibroblast ( CEF) cell cultures and their glycoprotein G gene sequence was closely related to the G gene of aMPV/C Colorado reference virus. Three-day-old commercial or SPF turkeys were inoculated oculonasally with wild bird aMPV/C P3 isolates. At 5 and 7 days post-inoculation (DPI), severe clinical signs were observed in both of the AC and CG virus-exposed groups. Viral RNA was detected in tracheal swabs by reverse transcriptase polymerase chain reaction (RT-PCR). In addition, immunohistochemistry showed virus replication in the nasal turbinate and trachea. All virus-exposed turkeys developed positive antibody response by 14 DPI. Conclusions Our data demonstrate that aMPV/C wild bird isolates induced typical aMPV/C disease in the domestic turkeys. PMID:23363433

  11. DIAGNOSING LYMPHOPROLIFERATIVE DISEASE VIRUS IN LIVE WILD TURKEYS (MELEAGRIS GALLOPAVO) USING WHOLE BLOOD.

    PubMed

    Alger, Katrina; Bunting, Elizabeth; Schuler, Krysten; Jagne, Jarra; Whipps, Christopher M

    2015-12-01

    Lymphoproliferative disease virus (LPDV) is a retrovirus that infects wild and domestic turkeys ( Meleagris gallopavo ). The first cases of LPDV in the United States were diagnosed in 2009, and subsequent surveillance has revealed the virus to be widespread in wild turkey populations throughout the eastern half of the country. More research is needed to determine whether LPDV is having a negative effect on turkey populations, but progress has been impeded by the lack of a simple method for diagnosing the virus in living birds. Infected animals may appear asymptomatic, and diagnostics currently rely on tissue or bone marrow, which can be difficult to obtain. This study investigated the reliability of polymerase chain reaction (PCR) to detect LPDV in whole blood, compared with previous methods using buffy coat (concentrated white blood cells) and bone marrow. Paired samples of whole blood and buffy coat were collected from 137 live turkeys and paired samples of whole blood and bone marrow were collected from 32 turkeys postmortem. Compared with buffy coat, whole blood had 97% sensitivity and 100% specificity. When compared with bone marrow, whole blood had 100% sensitivity and 89% specificity. Both comparisons had a high degree of agreement using Cohen's kappa statistic. Based on these results, PCR of whole blood provides detection of LPDV in living birds that is on par with both buffy coat and bone marrow. PMID:26667537

  12. Impacts of anthropogenic factors on land degradation during the anthropocene in Turkey.

    PubMed

    Curebal, Isa; Efe, Recep; Soykan, Abdullah; Sonmez, Suleyman

    2015-01-01

    The aim of the present study was to determine the factors that effected the beginning of the Anthropogenic Era (human age) in Turkey and formation of biomes. Destruction of vegetation, soil erosion and land degradation are the most important factors in the formation of anthropogenic biomes in Turkey. For this reason, first of all, a literature review about land degradation, which has been going on for past 300 years in Turkey, and about its causes was made. Changes that have occurred over the last 70 years were studied with the help of aerial photos and satellite images. In addition, studies we have conducted in the last 35 years have contributed substantially to the determination of the extent of the destruction of vegetation and land degradation in Turkey. As a result of research based on literature reviews and fieldwork, the impact of humans on the natural habitat were identified, and the current situation was studied. The findings about the current situation that emerged due to human impact were then transferred to an electronic environment, and a map of anthropogenic biomes was produced with the help of ArcGIS Desktop software. Based on the results obtained, one can say that the natural habitat has considerably changed over the last 200 years; vegetation has been damaged, and land degradation has become faster because of human activities. These results indicate that 97% of natural biomes have become anthropogenic biomes, and this change has become more obvious during 20h century in Turkey. The results also show that the change has been more influential after 1950. PMID:26591882

  13. Propagation and characterization of turkey reoviruses isolated in Germany, 2004-2008

    Technology Transfer Automated Retrieval System (TEKTRAN)

    From 2004 to 2008, suspected avian reoviruses were isolated from turkey flocks in ten counties in Germany. The age of birds at isolation ranged from 9 to 54 days. The suspected avian reoviruses elicited characteristic cytopathic effect (CPE) in chicken embryo kidney (CEK) cell culture. In 2009, CEK ...

  14. Effect of Cookery and Holding on Hams and Turkey Rolls Contaminated with Clostridium perfringens1

    PubMed Central

    Strong, Dorothy H.; Ripp, Nancy M.

    1967-01-01

    Canned hams, turkey rolls, and ground-beef casseroles were inoculated with a mixture of vegetative cells and spores of selected strains of Clostridium perfringens, in approximately known numbers. After cooking and holding at different temperatures for various times, samples of the food were plated directly on sulfadiazine-polymixin-sulfite-agar. In all cases, small but measurable percentages of the organisms survived cookery. The number of cells viable after cookery of the ham or turkey was influenced by the position of the slice of meat in the roast as well as by the final temperature to which the product was heated. Plate counts for turkey or beef casserole held at temperatures in the range of 5 to 10 C for 48 hr indicated stabilization of the population or a tendency to decrease. At 24 C, the multiplication of cells was apparent in 4 hr and rapid in 6 hr. When the food was maintained at 68 C, populations remained viable for 6 hr and the counts did not change markedly. In turkey maintained at 37 C, the number of cells increased sharply within 4 hr. PMID:4294821

  15. Effect of cookery and holding on hams and turkey rolls contaminated with Clostridium perfringens.

    PubMed

    Strong, D H; Ripp, N M

    1967-09-01

    Canned hams, turkey rolls, and ground-beef casseroles were inoculated with a mixture of vegetative cells and spores of selected strains of Clostridium perfringens, in approximately known numbers. After cooking and holding at different temperatures for various times, samples of the food were plated directly on sulfadiazine-polymixin-sulfite-agar. In all cases, small but measurable percentages of the organisms survived cookery. The number of cells viable after cookery of the ham or turkey was influenced by the position of the slice of meat in the roast as well as by the final temperature to which the product was heated. Plate counts for turkey or beef casserole held at temperatures in the range of 5 to 10 C for 48 hr indicated stabilization of the population or a tendency to decrease. At 24 C, the multiplication of cells was apparent in 4 hr and rapid in 6 hr. When the food was maintained at 68 C, populations remained viable for 6 hr and the counts did not change markedly. In turkey maintained at 37 C, the number of cells increased sharply within 4 hr. PMID:4294821

  16. Counseling in Turkey: An Evolving Field

    ERIC Educational Resources Information Center

    Stockton, Rex; Guneri, Oya Yerin

    2011-01-01

    This article provides a brief history of counseling and addresses the current issues and future trends of counseling in Turkey. Special emphasis is placed on the factors that impede the development of school counseling as a discipline.

  17. Applied andrology in chickens and turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The theories and practices of applied andrology in commercial poultry species (turkey, layer chicken and broiler chicken) are reviewed. Poultry male reproductive biology, including reproductive anatomy and spermatogenesis, is compared with mammalian livestock species. A detailed description of pou...

  18. Space Solar Power: Satellite Concepts

    NASA Technical Reports Server (NTRS)

    Little, Frank E.

    1999-01-01

    Space Solar Power (SSP) applies broadly to the use of solar power for space related applications. The thrust of the NASA SSP initiative is to develop concepts and demonstrate technology for applying space solar power to NASA missions. Providing power from satellites in space via wireless transmission to a receiving station either on earth, another celestial body or a second satellite is one goal of the SSP initiative. The sandwich design is a satellite design in which the microwave transmitting array is the front face of a thin disk and the back of the disk is populated with solar cells, with the microwave electronics in between. The transmitter remains aimed at the earth in geostationary orbit while a system of mirrors directs sunlight to the photovoltaic cells, regardless of the satellite's orientation to the sun. The primary advantage of the sandwich design is it eliminates the need for a massive and complex electric power management and distribution system for the satellite. However, it requires a complex system for focusing sunlight onto the photovoltaic cells. In addition, positioning the photovoltaic array directly behind the transmitting array power conversion electronics will create a thermal management challenge. This project focused on developing designs and finding emerging technology to meet the challenges of solar tracking, a concentrating mirror system including materials and coatings, improved photovoltaic materials and thermal management.

  19. The karyotype analysis of Pistacia vera L. from Turkey.

    PubMed

    Ayaz, Emine; Namli, Süreyya

    2009-01-01

    A detailed karyotype analysis was developed for Pistacia vera L. grown in Turkey. In vitro roots obtained from mature seeds were used as plant material. The chromosome number of P. vera L. was found to be 2n = 30 at c-metaphase of mitosis cell investigated for all of the materials. Centromere type of all chromosomes were determinated as median, submedian, subtelocentric, telocentric and total lengths of chromosome pairs were found between 35.4 and 5.97 microm. An idiogram was constructed from the average chromosome length, arm ratio and centomere type for each of the chromosome pairs. PMID:19488926

  20. The Slate turkey: a model for secondary angle closure glaucoma.

    PubMed

    de Kater, A W; Smyth, J R; Rosenquist, R C; Epstein, D L

    1986-12-01

    An inherited eye disease leading to a secondary angle closure glaucoma has been observed in turkeys (Meleagris gallapavo) of the Slate variety. The initial indications of the disease involve a low grade aqueous cell and flare reaction, associated with progressive posterior synechiae formation resulting in pupillary block and iris bombé. A midperipheral iridocorneal adhesion follows, accompanied by corneal edema, breaks in Descemet's membrane, and buphthalmos. IOP is not elevated substantially until a complete iris bombé occurs. Expression of the defect is sex-influenced, with females exhibiting the most severe pathological changes. PMID:3793405

  1. Second medical use in Turkey.

    PubMed

    Baklaci, Ezgi; Altınay, Merve

    2016-07-01

    Turkish patent legislation complies with European Patent Convention (EPC) 1973 and EPC 2000, but does not have a corresponding provision. This triggers a debate in Turkish Law, where no regulations address protection of second (or subsequent) use. Turkish validations of European patents concerning second medical uses that have been granted within the scope of EPC 2000. However, the approach to national patent applications and patents entered to Turkey through Patent Cooperation Treaty is still questionable since the Patent Decree Law is not offering an explicit protection to second medical use and European Board of Appeal decisions (especially G5/83) are not binding for Turkish authorities. This article overviews the current approach of the Turkish legal system to second medical use patents. PMID:27334394

  2. Fatal poisonings in Trabzon (Turkey).

    PubMed

    Birincioglu, Ismail; Karadeniz, Hulya; Teke, Hacer Yasar

    2011-05-01

    The aim of this study was to present the characteristics of medicolegal autopsies of fatal poisonings in Trabzon (Turkey), performed from 1998 to 2008, to contribute to the available data on this topic. A retrospective study of the forensic records and the toxicological data of all autopsies performed over that period revealed that 285 cases (6.34%) of the 4492 total autopsies performed were attributed to fatal poisoning. Major toxic substances were classified in five categories as follows: carbon monoxide (CO), insecticides, prescription medications, narcotic drugs, and alcohol (methyl and ethyl). CO was the most frequent cause of death (63.2%), followed by insecticides (17.2%), prescription medications and narcotic drugs (9.8%), alcohol (7.7%), and others (mushroom, rodenticide, and botulism) (2.1%). Ages of the patients ranged from 1 to 86 years (21.55 ± 36.56). PMID:21447071

  3. ASPEC: Solar power satellite

    NASA Technical Reports Server (NTRS)

    1991-01-01

    The solar power satellite (SPS) will provide a clean, reliable source of energy for large-scale consumption. The system will use satellites in geostationary orbits around the Earth to capture the Sun's energy. The intercepted sunlight will be converted to laser beam energy that can be transmitted to the Earth's surface. Ground systems on the Earth will convert the transmissions from space into electric power. The preliminary design for the SPS consists of one satellite in orbit around the Earth transmitting energy to a single ground station. The SPS design uses multilayer solar cell technology arranged on a 20 km squared planar array to intercept sunlight and convert it to an electric voltage. Power conditioning devices then send the electricity to a laser, which transmits the power to the surface of the Earth. A ground station will convert the beam into electricity. Typically, a single SPS will supply 5 GW of power to the ground station. Due to the large mass of the SPS, about 41 million kg, construction in space is needed in order to keep the structural mass low. The orbit configuration for this design is to operate a single satellite in geosynchronous orbit (GEO). The GEO allows the system to be positioned above a single receiving station and remain in sunlight 99 percent of the time. Construction will take place in low Earth orbit (LEO); array sections, 20 in total, will be sailed on solar wind out to the GEO location in 150 days. These individual transportation sections are referred to as solar sailing array panels (SSAP's). The primary truss elements used to support the array are composed of composite tubular members in a pentahedral arrangement. Smart segments consisting of passive and active damping devices will increase the control of dynamic SPS modes.

  4. Ghrelin stimulates myogenic differentiation in a mouse muscle satellite cell line and in primary cultures of bovine myoblasts.

    PubMed

    Montoya-Flores, D; Mora, O; Tamariz, E; González-Dávalos, L; González-Gallardo, A; Antaramian, A; Shimada, A; Varela-Echavarría, A; Romano-Muñoz, J L

    2012-08-01

    Ghrelin is an acylated hormone that influences food intake, energy metabolism and reproduction, among others. Ghrelin may also stimulate proliferating myoblast cell differentiation and multinucleated myotube fusion. The aim of this work was to assess the effect of human ghrelin (hGHRL) and human ghrelin fragment 1-18 (hGHRL1-18) on myoblast differentiation by means of mRNA expression and protein level. Two types of cells were tested, the cell line i28 obtained from mouse skeletal muscle and primary cultures of bovine myoblasts. Both ghrelin and its N-terminal fragment hGHRL1-18 were used at concentrations of 0, 0.01, 0.1, 1, 10 and 100 nm. Treatments were applied to pre-confluent cultures and were maintained for 4 days. We determined that between 0.1 and 100 nm, hGHRL and hGRHL1-18 had similar effects on myogenic differentiation of i28 cells (p < 0.01). On the other hand, only the higher concentrations (10 and 100 nm) of hGHRL stimulated bovine myoblast differentiation. These results could be attributed to the presence, in both i28 cells and in bovine myoblasts, of the mRNA for GHS-R1a and CD36 receptors. The use of ghrelin in livestock production is still questionable because of the limited effects shown in this study, and additional research is needed in this field. PMID:21777295

  5. Turkey vulture and California condor

    USGS Publications Warehouse

    Pattee, O.H.; Wilbur, S.R.

    1989-01-01

    Populations of turkey vultures in the western states appear stable, with no evidence of recent significant changes in distribution. Turkey vultures occupy a variety of habitats, nest in diverse situations and utilize a wide variety of carrion. Consequently, no particular limiting factor is likely to have a major effect on the total population. California condor numbers, in contrast, have continued to decline. With the capture of the last wild bird in 1987, the species has been extirpated from the wild. Reestablishment will depend on production and introduction of captive-reared birds, hopefully within the next 10 years. In the 18th century, condors inhabited areas along the Pacific coast from British Columbia to Baja California. Since 1950, the range has been restricted to a six county area adjacent to the southern San Joaquin Valley of California. Within this area, there appears to be no shortage of suitable nest sites; all recently used nest sites are within federally-controlled lands. Suitable foraging grounds have continued to diminish and are now largely limited to private rangelands and some Bureau of Land Management rangelands within the foothills of the San Joaquin Valley. Only these areas continue to supply the large mammal carcasses that the California condor needs for survival. The habitat of the condor is subject to a variety of land use practices and development pressures. Excessive mortality, coupled with low reproductive potential, continues to threaten the recovery of the species. Development of management practices to reduce mortality, particularly those that are contaminant-related, and of a preserve design to insure adequate habitat for the reintroduced population are still necessary for eventual recovery of the species.

  6. Satellite Glial Cells Surrounding Primary Afferent Neurons Are Activated and Proliferate during Monoarthritis in Rats: Is There a Role for ATF3?

    PubMed Central

    Nascimento, Diana Sofia Marques; Castro-Lopes, José Manuel; Neto, Fani Lourença Moreira

    2014-01-01

    Joint inflammatory diseases are debilitating and very painful conditions that still lack effective treatments. Recently, glial cells were shown to be crucial for the development and maintenance of chronic pain, constituting novel targets for therapeutic approaches. At the periphery, the satellite glial cells (SGCs) that surround the cell bodies of primary afferents neurons in the dorsal root ganglia (DRG) display hypertrophy, proliferation, and activation following injury and/or inflammation. It has been suggested that the expression of neuronal injury factors might initially trigger these SGCs-related events. We then aimed at evaluating if SGCs are involved in the establishment/maintenance of articular inflammatory pain, by using the monoarthritis (MA) model, and if the neuronal injury marker activating transcriptional factor 3 (ATF3) is associated with these SGCs' reactive changes. Western Blot (WB) analysis of the glial fibrillary acidic protein (GFAP) expression was performed in L4-L5 DRGs from control non-inflamed rats and MA animals at different time-points of disease (4, 7, and 14d, induced by complete Freund's adjuvant injection into the left hind paw ankle joint). Data indicate that SGCs activation is occurring in MA animals, particularly after day 7 of disease evolution. Additionally, double-immunostaining for ATF3 and GFAP in L5 DRG sections shows that SGCs's activation significantly increases around stressed neurons at 7d of disease, when compared with control animals. The specific labelling of GFAP in SGCs rather than in other cell types was also confirmed by immunohistochemical labeling. Finally, BrdU incorporation indicates that proliferation of SGCs is also significantly increased after 7 days of MA. Data indicate that SGCs play an important role in the mechanisms of articular inflammation, with 7 days of disease being a critical time-point in the MA model, and suggest that ATF3 might be involved in SGCs' reactive changes such as activation. PMID

  7. Factors Influencing International Students' Choice to Study in Turkey and Challenges They Experience in Turkey

    ERIC Educational Resources Information Center

    Özoglu, Murat; Gür, Bekir S.; Coskun, Ipek

    2015-01-01

    Turkey is increasingly becoming a regional hub for international students. The number of international students in Turkish universities has grown by almost 300% in the last decade. The current internationalization efforts of the Turkish government and universities have the potential to make Turkey an even more attractive destination for…

  8. Policy Options for Turkey: A Critique of the Interpretation and Utilization of PISA Results in Turkey

    ERIC Educational Resources Information Center

    Gur, Bekir S.; Celik, Zafer; Ozoglu, Murat

    2012-01-01

    In this article we provide a critique of the interpretation and utilization of Programme for International Student Assessment (PISA) results by the National Education Authorities in Turkey. First, we define and explain what OECD's PISA is. Second, we make an overview of the media coverage in Turkey of the PISA 2003 and 2006 results. Third, we…

  9. Small Glacier Area Studies: A New Approach for Turkey

    NASA Technical Reports Server (NTRS)

    Yavasli, Dogukan D.; Tucker, Compton J.

    2012-01-01

    Many regions of Earth have glaciers that have been neglected for study because they are small. We report on a new approach to overcome the problem of studying small glaciers, using Turkey as an example. Prior to our study, no reliable estimates of Turkish glaciers existed because of a lack of systematic mapping, difficulty in using Landsat data collected before 1982, snowpack vs. glacier ice differentiation using existing satellite data and aerial photography, the previous high cost of Landsat images, and a lack of high-resolution imagery of small Turkish glaciers. Since 2008, a large number of < 1 m satellite images have become available at no cost to the research community. In addition, Landsat data are now free of charge from the U.S. Geological Survey, enabling the use of multiple images. We used 174 Landsat and eight high-resolution satellite images to document the areal extent of Turkish glaciers from the 1970s to 2007-2011. Multiple Landsat images, primarily Thematic Mapper (TM) data from 1984 to 2011, enabled us to minimize differentiation problems between snow and glacier ice, a potential source of error. In addition, we used Ikonos, Quickbird, and World View-1 & -2 very high-resolution imagery to evaluate our TM accuracies and determine the area of nine smaller glaciers in Turkey. We also used five Landsat-3 Return Beam Videcon (RBV) 30 m pixel resolution images, all from 1980, for six glaciers. The total area of Turkish glaciers decreased from 23 km2 in the 1970s to 10.1 km2 in 2007-2011. By 2007-2011, six Turkish glaciers disappeared, four were < 0.3 km2, and only three were 1.0 km2 or larger. No trends in precipitation from 1970 to 2006 and cloud cover from 1980 to 2010 were found, while surface temperatures increased, with summer minimum temperatures showing the greatest increase. We conclude that increased surface temperatures during the summer were responsible for the 56% recession of Turkish glaciers from the 1970s to 2006-2011.

  10. Evaluation program for secondary spacecraft cells: Initial evaluation tests of General Electric Company 6.0 ampere hour nickle cadmium spacecraft cells for the dynamic explorer satellite program

    NASA Technical Reports Server (NTRS)

    Harkness, J. D.

    1980-01-01

    Evaluation tests of 10 nickel cadmium cells are described. Although pressures were greater than what normally was exhibited by General Electric cells in the past, it is recommended that these cells be placed on life test simulating the predicted Dynamic Explorer flight profiles.

  11. Odyssey personal communications satellite system

    NASA Technical Reports Server (NTRS)

    Spitzer, Christopher J.

    1993-01-01

    The spectacular growth of cellular telephone networks has proved the demand for personal communications. Large regions of the world are too sparsely populated to be economically served by terrestrial cellular communications. Since satellites are well suited to this application, TRW filed with the FCC on May 31, 1993 for the Odyssey construction permit. Odyssey will provide high quality wireless communication services worldwide from satellites. These services will include: voice, data, paging, and messaging. Odyssey will be an economical approach to providing communications. A constellation of 12 satellites will be orbited in three, 55 deg. inclined planes at an altitude of 10,354 km to provide continuous coverage of designated regions. Two satellites will be visible anywhere in the world at all times. This dual visibility leads to high line-of-sight elevation angles, minimizing obstructions by terrain, trees and buildings. Each satellite generates a multibeam antenna pattern that divides its coverage area into a set of contiguous cells. The communications system employs spread spectrum CDMA on both the uplinks and downlinks. This signaling method permits band sharing with other systems and applications. Signal processing is accomplished on the ground at the satellite's 'Gateway' stations. The 'bent pipe' transponders accommodates different regional standards, as well as signaling changes over time. The low power Odyssey handset will be cellular compatible. Multipath fade protection is provided in the handset.

  12. Solar array experiments on the Sphinx satellite

    NASA Technical Reports Server (NTRS)

    Stevens, N. J.

    1973-01-01

    The Space Plasma, High Voltage Interaction Experiment (SPHINX) is the name given to an auxiliary payload satellite scheduled to be launched in January 1974. The principal experiments carried on this satellite are specifically designed to obtain the engineering data on the interaction of high voltage systems with the space plasma. The classes of experiments are solar array segments, insulators, insulators with pin holes and conductors. The satellite is also carrying experiments to obtain flight data on three new solar array configurations; the edge illuminated-multijunction cells, the Teflon encased cells and the violet cells.

  13. Application of AirCell Cellular AMPS Network and Iridium Satellite System Dual Mode Service to Air Traffic Management

    NASA Technical Reports Server (NTRS)

    Shamma, Mohammed A.

    2004-01-01

    The AirCell/Iridium dual mode service is evaluated for potential applications to Air Traffic Management (ATM) communication needs. The AirCell system which is largely based on the Advanced Mobile Phone System (AMPS) technology, and the Iridium FDMA/TDMA system largely based on the Global System for Mobile Communications(GSM) technology, can both provide communication relief for existing or future aeronautical communication links. Both have a potential to serve as experimental platforms for future technologies via a cost effective approach. The two systems are well established in the entire CONUS and globally hence making it feasible to utilize in all regions, for all altitudes, and all classes of aircraft. Both systems have been certified for air usage. The paper summarizes the specifications of the AirCell/Iridium system, as well as the ATM current and future links, and application specifications. the paper highlights the scenarios, applications, and conditions under which the AirCell/Iridium technology can be suited for ATM Communication.

  14. Feasibility and acceptability of a text messaging-based smoking cessation program in ankara, Turkey.

    PubMed

    Ybarra, Michele L; Holtrop, Jodi S; Bağci Bosi, A Tülay; Bilir, Nazmi; Korchmaros, Josephine D; Salih Emri, A K

    2013-08-01

    Data from high-income countries suggest that cell phone-based smoking cessation programs have the potential to affect cessation rates. There is a paucity of research, however, about the feasibility of cell phone-based smoking cessation programs in lower income countries that have higher smoking prevalence rates. A one-arm feasibility and acceptability pilot study of SMS Turkey, a text messaging-based smoking cessation program, was conducted in Ankara, the capital of Turkey. The authors recruited 75 daily smokers who were seriously thinking about quitting in the subsequent 30 days into the 6-week SMS Turkey program. Recruitment was completed in 4 months. Participant retention was high: Almost all (96%) completed the program, and 84% provided 12-week follow-up data. Most (89%) of the respondents who completed the 4-week follow-up measures (n = 38, 51%) said that the text messages were easy to understand and referred to what they were experiencing and feeling during the quitting process (78%). On the basis of intention to treat, 13% of participants (n = 10) reported, at 12-week follow-up, continuous abstinence since their quit date, confirmed by carbon monoxide readings. The cell phone text messaging-based smoking cessation intervention appears feasible and acceptable in Ankara, Turkey. PMID:23627304

  15. Iodine Satellite

    NASA Technical Reports Server (NTRS)

    Kamhawi, Hani; Dankanich, John; Martinez, Andres; Petro, Andrew

    2015-01-01

    The Iodine Satellite (iSat) spacecraft will be the first CubeSat to demonstrate high change in velocity from a primary propulsion system by using Hall thruster technology and iodine as a propellant. The mission will demonstrate CubeSat maneuverability, including plane change, altitude change and change in its closest approach to Earth to ensure atmospheric reentry in less than 90 days. The mission is planned for launch in fall 2017. Hall thruster technology is a type of electric propulsion. Electric propulsion uses electricity, typically from solar panels, to accelerate the propellant. Electric propulsion can accelerate propellant to 10 times higher velocities than traditional chemical propulsion systems, which significantly increases fuel efficiency. To enable the success of the propulsion subsystem, iSat will also demonstrate power management and thermal control capabilities well beyond the current state-of-the-art for spacecraft of its size. This technology is a viable primary propulsion system that can be used on small satellites ranging from about 22 pounds (10 kilograms) to more than 1,000 pounds (450 kilograms). iSat's fuel efficiency is ten times greater and its propulsion per volume is 100 times greater than current cold-gas systems and three times better than the same system operating on xenon. iSat's iodine propulsion system consists of a 200 watt (W) Hall thruster, a cathode, a tank to store solid iodine, a power processing unit (PPU) and the feed system to supply the iodine. This propulsion system is based on a 200 W Hall thruster developed by Busek Co. Inc., which was previously flown using xenon as the propellant. Several improvements have been made to the original system to include a compact PPU, targeting greater than 80 percent reduction in mass and volume of conventional PPU designs. The cathode technology is planned to enable heaterless cathode conditioning, significantly increasing total system efficiency. The feed system has been designed to

  16. Caldera formation at Tendurek, East Turkey

    NASA Astrophysics Data System (ADS)

    Bathke, H.; Sudhaus, H.; Shirzaei, M.; Walter, T. R.

    2012-04-01

    Volcanoes of eastern Turkey have been historically active and are located in an active tectonic system with abundant faults and fissures. Tendurek is a low relief shield volcano with an edifice height of about 3580 m and covers an area of 650km2. It has an elliptical shape and the two summit craters and a flank crater are arranged in the direction of the long axis. The summit area is surrounded by an also elliptical ring fracture system with a 9km long axis and a 6km minor axis. This system is more developed in the south than in the north, therefore it is called a half caldera. Tendurek is located in an active tectonic region with right lateral motion near to the Balik Gölü fault, and has been affected by significant tectonic earthquakes, such as in 1840 (M7.4). The last eruption occurred in 1855, since then it is considered to be dormant. Little is known about the deep magma plumbing system, and the state of its current activity. Here we report on a radar interferometric study where we combine SAR images acquired by the Envisat satellite in the years from 2004- 2008 and 2003- 2010 in ascending and descending orbits, respectively. We used the software's ROI_Pac and Doris to create interferograms. The StaMPS software was used to analyze the temporal evolution and to estimate a mean annual velocity of the deformation signal in both tracks. Due to the poor coherence in the summit area, less stable pixel have been identified there in the processing. Where at the lower flanks and further away from the volcanic edifice a lot of stable pixel could be identified. These data allows us to investigate the ground deformation pattern at unprecedented spatial detail. We observe various localized but evident deformation occurrences, associated with volcanic activity at Tendurek volcano. Deformation affected the upper region of the volcano, including the summit craters within the dimension of the previously mentioned ring fault system at a very low rate. By using a genetic

  17. Electric power for space satellites

    NASA Technical Reports Server (NTRS)

    Mackenzie, C. M.

    1974-01-01

    The development of electric power systems for satellites is discussed as an evolutionary process requiring the integration of power generation, power storage, and power control and distribution. The growth of space electric power systems is traced. The capabilities and limitations of the various elements (i.e. silicon solar cells) are discussed together with their impact on future technological growth.

  18. 'Cold Turkey' May Work Best for Quitting Smoking

    MedlinePlus

    ... nlm.nih.gov/medlineplus/news/fullstory_157753.html 'Cold Turkey' May Work Best for Quitting Smoking Stopping ... four weeks, nearly half of those who quit "cold turkey" were still not smoking. But, among people ...

  19. Identification of miR-2400 gene as a novel regulator in skeletal muscle satellite cells proliferation by targeting MYOG gene.

    PubMed

    Zhang, Wei Wei; Tong, Hui Li; Sun, Xiao Feng; Hu, Qian; Yang, Yu; Li, Shu Feng; Yan, Yun Qin; Li, Guang Peng

    2015-08-01

    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. PMID:26047700

  20. 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

    PubMed Central

    Yablonka-Reuveni, Zipora; Danoviz, Maria E.; Phelps, Michael; Stuelsatz, Pascal

    2015-01-01

    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 Fgfr genes, 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. PMID:26074812

  1. Determining and Monitoring the Water Quality of Kizilirmak River of Turkey: First Results

    NASA Astrophysics Data System (ADS)

    Gursoy, O.; Birdal, A. C.; Ozyonar, F.; Kasaka, E.

    2015-04-01

    Water resources are getting more and more important with each passing day in case of survival of humanity. For this reason, assessing water resources' quality and also monitoring them have attracted lots of attention in the recent years. Remote sensing has been growing widely in the last decade and its resources are very usable when it comes to water resources management. In this study, by using remote sensing technology, satellite images that have 350 to 1050 nanometres wavelength band sensors (e.g. CHRIS Proba) are used to determine the quality of the Kizilirmak River's water. Kizilirmak River is born and also pours out to sea in country limits of Turkey. It is the longest river of the country by the length of 1355 kilometres. Through the river's resources, ground based spectral measurements are made to identify the quality differences of the water at the test spots that have been determined before. In this context at Imranli, where the river contacts civilization for the first time, which is located in Sivas city of Turkey, samples are gathered in order to do ground based spectroradiometer measurements. These samples are gathered simultaneously with the image acquiring time of CHRIS Proba satellite. Spectral signatures that are obtained from ground measurements are used as reference data in order to classify CHRIS Proba satellite's hyperspectral images over the study area. Satellite images are classified based on Chemical Oxygen Demand (COD), Turbidity and Electrical Conductivity (EC) attributes. As a result, interpretations obtained from classified CHRIS Proba satellite hyperspectral images of the study area are presented.

  2. Cycle life evaluation of 3 Ah Li{subx}Mn{sub2}O{sub4}-based lithium-ion secondary cells for low-earth-orbit satellites. I. Full cell results.

    SciTech Connect

    Brown, S.; Ogawa, K.; Kumeuchi, Y.; Enomoto, S.; Uno, M.; Saito, H.; Sone, Y.; Abraham, D.; Lindbergh, G.; Chemical Sciences and Engineering Division; Royal Inst. of Tech.; Advanced Engineering Services Co., Ltd.; NEC-Tokin Corp.; Inst. of Space and Astronautical Science

    2008-01-01

    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.

  3. Asteroid Satellites

    NASA Astrophysics Data System (ADS)

    Merline, W. J.

    2001-11-01

    Discovery and study of small satellites of asteroids or double asteroids can yield valuable information about the intrinsic properties of asteroids themselves and about their history and evolution. Determination of the orbits of these moons can provide precise masses of the primaries, and hence reliable estimates of the fundamental property of bulk density. This reveals much about the composition and structure of the primary and will allow us to make comparisons between, for example, asteroid taxonomic type and our inventory of meteorites. The nature and prevalence of these systems will also give clues as to the collisional environment in which they formed, and have further implications for the role of collisions in shaping our solar system. A decade ago, binary asteroids were more of a theoretical curiosity. In 1993, the Galileo spacecraft allowed the first undeniable detection of an asteroid moon, with the discovery of Dactyl, a small moon of Ida. Since that time, and particularly in the last year, the number of known binaries has risen dramatically. Previously odd-shaped and lobate near-Earth asteroids, observed by radar, have given way to signatures indicating, almost certainly, that at least four NEAs are binary systems. The tell-tale lightcurves of several other NEAs reveal a high likelihood of being double. Indications are that among the NEAs, there may be a binary frequency of several tens of percent. Among the main-belt asteroids, we now know of 6 confirmed binary systems, although their overall frequency is likely to be low, perhaps a few percent. The detections have largely come about because of significant advances in adaptive optics systems on large telescopes, which can now reduce the blurring of the Earth's atmosphere to compete with the spatial resolution of space-based imaging (which itself, via HST, is now contributing valuable observations). Most of these binary systems have similarities, but there are important exceptions. Searches among other

  4. Outer planet satellites

    SciTech Connect

    Schenk, P.M. )

    1991-01-01

    Recent findings on the outer-planet satellites are presented, with special consideration given to data on the rheologic properties of ice on icy satellites, the satellite surfaces and exogenic processes, cratering on dead cratered satellites, volcanism, and the interiors of outer-planet satellites. Particular attention is given to the state of Titan's surface and the properties of Triton, Pluto, and Charon. 210 refs.

  5. Effect of coronavirus infection on reproductive performance of turkey hens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Turkey coronavirus (TCoV) infection causes enteritis in turkeys of varying ages with high mortality in young birds. In older birds, field evidence indicates possible involvement of TCoV in egg production drops in turkey hens. However, no experimental studies have been conducted to demonstrate TCoV...

  6. Turkey opens electricity markets as demand grows

    SciTech Connect

    McKeigue, J.; Da Cunha, A.; Severino, D.

    2009-06-15

    Turkey's growing power market has attracted investors and project developers for over a decade, yet their plans have been dashed by unexpected political or financial crises or, worse, obstructed by a lengthy bureaucratic approval process. Now, with a more transparent retail electricity market, government regulators and investors are bullish on Turkey. Is Turkey ready to turn the power on? This report closely examine Turkey's plans to create a power infrastructure capable of providing the reliable electricity supplies necessary for sustained economic growth. It was compiled with on-the-ground research and extensive interview with key industrial and political figures. Today, hard coal and lignite account for 21% of Turkey's electricity generation and gas-fired plants account for 50%. The Alfin Elbistan-B lignite-fired plant has attracted criticism for its lack of desulfurization units and ash dam facilities that have tarnished the industry's image. A 1,100 MW hard-coal fired plant using supercritical technology is under construction. 9 figs., 1 tab.

  7. Turkey liver - a chromium enriched food source

    SciTech Connect

    Polansky, M.M.; Bryden, N.A.; Richards, M.; Anderson, R.A.

    1986-03-01

    There are presently no known foods for humans that are particularly good sources of chromium. As a means of obtaining Cr enriched foods, turkeys were fed diets containing various levels of supplemental chromium. Four groups of 6-month old turkey hens were fed either the basal diet for laying hens or this diet supplemented with 25, 100 or 200 ..mu..g of chromium as chromium chloride per g of diet. Liver Cr concentration of the turkeys sacrificed after 1 week increased from 7 ng/g (wet wt) while consuming the basal diet to 15, 48 and 68 ng/g, respectively, while consuming the diets with supplemental chromium. Comparable values for the turkeys sacrificed after 5 weeks were 2, 43, 170 and 325 ng/g. Similar trends but higher chromium values were observed for kidney samples. The chromium contents of the dark and white meat and eggs were not altered significantly. Chromium concentrations of the pancreas, gizzard and heart increased marginally; final chromium concentrations were less than 23 ng/g even after 5 weeks on the highest level of supplemental chromium. Chromium content of spleen and lungs was approximately 2-fold higher than that of the pancreas, gizzard or heart. Therefore, turkey liver is a food source suitable for Cr enrichment while the eggs, dark and white meat and other edible parts do not appear to be enriched following chromium supplementation.

  8. 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

    NASA Astrophysics Data System (ADS)

    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%).

  9. Further characterization of the agent causing coryza in turkeys.

    PubMed

    Jackwood, M W; Saif, Y M; Moorhead, P D; Dearth, R N

    1985-01-01

    A total of 128 isolates of Alcaligenes faecalis, from the respiratory tract of turkeys and chickens, were identified and divided into two types designated type I and type II. Type I isolates were pathogenic in poults, hemagglutinated guinea pig red blood cells (RBCs), and did not grow on minimal essential medium (MEM) agar, and most did not grow in 6.5% NaCl broth. Type II isolates were nonpathogenic and nonhemagglutinating and grew on MEM agar, and most grew in 6.5% NaCl broth. Hemagglutination of guinea pig RBCs was a reliable characteristic for distinguishing type I from type II isolates, and it correlated with pathogenicity. In serological studies using 62 type I and 21 type II isolates, cross-reactions were observed when type I but not type II antigens were used to test antisera in the microagglutination test. Eleven bacterial isolates, different from type I and type II isolates, were urease-positive. Although frequently isolated from turkeys with coryza, these isolates were nonpathogenic and were always found in association with type I A. faecalis. Urease-positive isolates and type I and type II A. faecalis isolates were stable following 50 in vitro passages. Bordetella avium sp. nov. (the nomenclature suggested in Europe for A. faecalis) was pathogenic in poults. The colonial morphology, biochemical characteristics, and hemagglutinating activity of B. avium sp. nov. were the same as those of type I A. faecalis isolates. Based on the results of these studies, it was concluded that type I A. faecalis is the etiologic agent of turkey coryza. PMID:4074238

  10. Basic sciences agonize in Turkey!

    NASA Astrophysics Data System (ADS)

    Akdemir, Fatma; Araz, Asli; Akman, Ferdi; Durak, Rıdvan

    2016-04-01

    In this study, changes from past to present in the departments of physics, chemistry, biology and mathematics, which are considered as the basic sciences in Turkey, are shown. The importance of basic science for the country emphasized and the status of our country was discussed with a critical perspective. The number of academic staff, the number of students, opened quotas according to years for these four departments at universities were calculated and analysis of the resulting changes were made. In examined graphics changes to these four departments were similar. Especially a significant change was observed in the physics department. Lack of jobs employing young people who have graduated from basic science is also an issue that must be discussed. There are also qualitative results of this study that we have discussed as quantitative. Psychological problems caused by unemployment have become a disease among young people. This study was focused on more quantitative results. We have tried to explain the causes of obtained results and propose solutions.

  11. The Mexican national satellite system

    NASA Astrophysics Data System (ADS)

    Sanchez Ruiz, M. E.; Briskman, R. D.

    1983-10-01

    The satellites, tracking, telemetry, command, and monitoring facilities, and the earth station complex for the Mexican national satellite system, Morelos, are described. The spacecraft are intended to provide educational television, rural telephony, data transmission, and business and industrial services. Scheduled for 1985 launch, the satellites will be placed in GEO and use the C and Ku bands with 12 narrow band and six wideband transponders. Spin-stabilized and solar cell powered, the functional mass will be 666 kg, including propellant. The solar panels will provide 940 W of power and 830 W will be available from NiCd batteries during eclipse conditions. The earth station will be located at Iztapalapa, which will have a 12 m antenna, redundant uplink and downlink radios, and command and ranging equipment. Back-up capability will be provided by a station at Tulancingo. Ku band and C band stations are in planning.

  12. Current leakage for low altitude satellites - Modeling applications. [simulation of high voltage solar cell array in ionospheric plasma environment

    NASA Technical Reports Server (NTRS)

    Konradi, A.; Mccoy, J. E.; Garriott, O. K.

    1979-01-01

    To simulate the behavior of a high voltage solar cell array in the ionospheric plasma environment, the large (90 ft x 55 ft diameter) vacuum chamber was used to measure the high-voltage plasma interactions of a 3 ft x 30 ft conductive panel. The chamber was filled with Nitrogen and Argon plasma at electron densities of up to 1,000,000 per cu cm. Measurements of current flow to the plasma were made in three configurations: (a) with one end of the panel grounded, (b) with the whole panel floating while a high bias was applied between the ends of the panel, and (c) with the whole panel at high negative voltage with respect to the chamber walls. The results indicate that a simple model with a constant panel conductivity and plasma resistance can adequately describe the voltage distribution along the panel and the plasma current flow. As expected, when a high potential difference is applied to the panel ends more than 95% of the panel floats negative with respect to the plasma.

  13. China's satellite communications discussed

    NASA Astrophysics Data System (ADS)

    Ruhou, Z.

    1986-04-01

    In 1972, China began to enter the age of satellite comunications, and it was realized that satellites could play a large role in television transmission in China. The experimental broadcasting of satellite television programs was begun in 1978, and satisfactory results were obtained. The success of the television transmission demonstration has led to important decisions regarding development of a domestic satellite communications system. Before specialized communications satellites are launched, the decision was made to lease an international communications satellite transmitter. The responsibility of the ground stations were discussed.

  14. Satellite orbit predictor

    NASA Technical Reports Server (NTRS)

    Friedman, Morton l.; Garrett, James, Major

    An analog aid to determine satellite coverage of Emergency Locator Transmitters Emergency Position Indicating Radio Beacon (ELT/EPIRB) distress incidence is discussed. The satellite orbit predictor is a graphical aid for determining the relationship between the satellite orbit, antenna coverage of the spacecraft and coverage of the Local User Terminal. The predictor allows the user to quickly visualize if a selected position will probably be detected and is composed of a base map and a satellite track overlay for each satellite.A table of equator crossings for each satellite is included.

  15. Effect of humidity on infection of turkeys with Alcaligenes faecalis.

    PubMed

    Slavik, M F; Skeeles, J K; Beasley, J N; Harris, G C; Roblee, P; Hellwig, D

    1981-01-01

    Turkeys maintained at 75% to 80% relative humidity were more adversely affected by Alcaligenes faecalis infection than turkeys maintained at 20 to 35% relative humidity. Alcaligenes faecalis was reisolated earlier and more often from turkeys maintained at the higher humidity. Clinically, the turkeys maintained at high humidity exhibited both sinusitis and conjunctivitis earlier than the turkeys at low humidity. In both groups, antibody titers as determined by a microagglutination test developed by 2 weeks postinoculation and started to decline after the third week, lymphocytosis was demonstrated at 1 week postinoculation, and a lymphopenia developed at 5 weeks postinoculation. PMID:7337613

  16. Functional characterization of the turkey macrophage migration inhibitory factor.

    PubMed

    Park, Myeongseon; Kim, Sungwon; Fetterer, Raymond H; Dalloul, Rami A

    2016-08-01

    Macrophage migration inhibitory factor (MIF) is a soluble protein that inhibits the random migration of macrophages and plays a pivotal immunoregulatory function in innate and adaptive immunity. The aim of this study was to clone the turkey MIF (TkMIF) gene, express the active protein, and characterize its basic function. The full-length TkMIF gene was amplified from total RNA extracted from turkey spleen, followed by cloning into a prokaryotic (pET11a) expression vector. Sequence analysis revealed that TkMIF consists of 115 amino acids with 12.5 kDa molecular weight. Multiple sequence alignment revealed 100%, 65%, 95% and 92% identity with chicken, duck, eagle and zebra finch MIFs, respectively. Recombinant TkMIF (rTkMIF) was expressed in Escherichia coli and purified through HPLC and endotoxin removal. SDS-PAGE analysis revealed an approximately 13.5 kDa of rTkMIF monomer containing T7 tag in soluble form. Western blot analysis showed that anti-chicken MIF (ChMIF) polyclonal antisera detected a monomer form of TkMIF at approximately 13.5 kDa size. Further functional analysis revealed that rTkMIF inhibits migration of both mononuclear cells and splenocytes in a dose-dependent manner, but was abolished by the addition of anti-ChMIF polyclonal antisera. qRT-PCR analysis revealed elevated transcripts of pro-inflammatory cytokines by rTkMIF in LPS-stimulated monocytes. rTkMIF also led to increased levels of IFN-γ and IL-17F transcripts in Con A-activated splenocytes, while IL-10 and IL-13 transcripts were decreased. Overall, the sequences of both the turkey and chicken MIF have high similarity and comparable biological functions with respect to migration inhibitory activities of macrophages and enhancement of pro-inflammatory cytokine expression, suggesting that turkey and chicken MIFs would be biologically cross-reactive. PMID:27062968

  17. Alcaligenes faecalis rhinotracheitis in Manitoba turkeys.

    PubMed

    Boycott, B R; Wyman, H R; Wong, F C

    1984-01-01

    An outbreak of alcaligenes rhinotracheitis occurred on one premises housing five turkey flocks totaling 25,000 poults. Prominent findings were severe respiratory difficulty resulting from excess mucus in the nasopharynx, lachrimation, and tracheal collapse. Sinus and tracheal cultures consistently yielded Alcaligenes faecalis. An adenovirus was isolated and four flocks became positive for CELO virus by agar-gel-precipitin (AGP) tests. Mortality by flocks ranged from 4% to 48%. Treatment was unsuccessful and appeared to increase the mortality rate. The course of the disease was about 6 weeks, and recovered turkeys were marketed 1 week later than the usual date. PMID:6525132

  18. A case of salinomycin intoxication in turkeys.

    PubMed

    Van Assen, Earl J

    2006-03-01

    A flock of 4287 heavy hybrid turkey hens were accidentally fed broiler premix containing salinomycin sodium and suffered a 34.5% death loss. Measures taken to ensure food safety for the remaining flock and consumer food safety included feed record studies, on-farm veterinary consultation, diagnostic laboratory studies, and CgFARAD and CFIA consultation. The remaining turkeys were processed 3 weeks after the initial toxicosis with no evidence of lesions that would render the product unfit for human consumption. PMID:16604983

  19. Galileo satellite antenna modeling

    NASA Astrophysics Data System (ADS)

    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.

  20. General Ecological Characteristics Based on GIS Methods in Poyrazlar Lake, Turkey

    NASA Astrophysics Data System (ADS)

    Ikiel, C.; Kilic, D. E.; Atalay Dutucu, A.

    2012-04-01

    General Ecological Characteristics Based on GIS Methods in Poyrazlar Lake, Turkey Cercis Ikiel Derya Evrim Kilic• Ayse Atalay Dutucu Sakarya University, Art and Science Faculty, Department of Geography, Sakarya, Turkey In this research, general ecological features in Poyrazlar lake is investigated. The study area is located in the east part of Marmara region and north-western part of the Adapazari plain (north-western part of Turkey) between the coordinates of 40°48'-40°52' N and 30°23'-30°30' E. Research area is within phytogeographical region of Euro-Siberian that is among flora and phytogeographical region of Turkey. The main element of vegetation consists Humid-Mild Deciduous forests (especially Quercus spp.) and hydrophyte plants (such as reeds and Nymphaea alba L.). Poyrazlar lake, that's water is fresh, is one of the important wetland areas in the region with its ecological characteristics. Especially the research area is haunted by various migratory birds and it is an important recreation area. The objective of this study is to analyze particularly the formation of Poyrazlar lake, ecological features of this area and negative influence of surrounding human activities in the area. For this purpose topography, geology, soil maps, forest arrangement plan, Spot 5 (2010 period) satellite image for current land use map and field observations data are used. These images are analyzed by utilizing data image processing techniques in ERDAS Imagine© 10.0 and ArcGIS© 10.0 software. Keywords: Ecology; Ecological Features; GIS; Alluvial Dam Lake; Poyrazlar Lake

  1. [Tularemia in Konya region, Turkey].

    PubMed

    Dikici, Nebahat; Ural, Onur; Sümer, Sua; Oztürk, Kayhan; Albayrak Yiğit, Ozgen; Katlanır, Eda; Keleş, Bahar

    2012-04-01

    Tularemia is a zoonotic infection caused by Francisella tularensis. In the recent years tularemia has become a re-emerging infection in Turkey with epidemics and also sporadic cases. Transmission occurs most often through consumption of contaminated water and food, direct contact with animals and insect/ tick bites. In this study, we evaluated clinical features and laboratory findings of 35 tularemia cases diagnosed during two outbreaks that occurred in two different villages during two different periods in Konya (located in Central Anatolia), Turkey and five sporadic cases. In both outbreaks, first (index) cases were admitted to our outpatient clinic with the complaints of cervical lympadenopathy. After diagnosis of tularemia, an organized team visited the villages to search if more cases existed. For microbiological diagnosis, blood, throat and tonsil swabs and lymph node aspirate specimens were collected from the suspected cases. Diagnostic tests (culture, serology, molecular methods) for tularemia were performed in reference center, Refik Saydam National Public Health Agency. Drinking and potable water samples from those villages were also collected by provincial health authorities. The cases (n= 14) that belonged to the first epidemics were detected in February 2010 and cases (n= 21) of the second epidemics in November- December 2010; five cases were followed as sporadic. The mean age of the 40 patients (25 females, 15 males) was 37.6 (age range: 5-80 years; five of them were pediatric group) years. The most common complaints of patients were cervical mass (90%), sore throat (63%), chills (60%) and fever (58%). The most frequently detected clinical findings were enlarged lymph nodes (n= 34, 85%), followed by tonsillitis (20%), skin lesions (15%) and conjunctivitis (8%). Most of the patients (82.5%) had been misdignosed as acute tonsillitis, suppurative lymphadenitis, tuberculous lymphadenitis and brucellosis, before their admission to our hospital and treated

  2. Operational EEW Networks in Turkey

    NASA Astrophysics Data System (ADS)

    Zulfikar, Can; Pinar, Ali

    2016-04-01

    There are several EEW networks and algorithms under operation in Turkey. The first EEW system was deployed in Istanbul in 2002 after the 1999 Mw7.4 Kocaeli and Mw7.1 Duzce earthquake events. The system consisted of 10 strong motion stations located as close as possible to the main Marmara Fault line. The system was upgraded by 5 OBS (Ocean Bottom Seismometer) in 2012 located in Marmara Sea. The system works in threshold based algorithm. The alert is given according to exceedance of certain threshold levels of amplitude of ground motion acceleration in certain time interval at least in 3 stations. Currently, there are two end-users of EEW system in Istanbul. The critical facilities of Istanbul Gas Distribution Company (IGDAS) and Marmaray Tube tunnel receives the EEW information in order to activate their automatic shut-off mechanisms. The IGDAS has their own strong motion network located at their district regulators. After receiving the EEW signal if the threshold values of ground motion parameters are exceeded the gas-flow is cut automatically at the district regulators. The IGDAS has 750 district regulators distributed in Istanbul. At the moment, the 110 of them are instrumented with strong motion accelerometers. As a 2nd stage of the on-going project, the IGDAS company proposes to install strong motion accelerometers to all remaining district regulators. The Marmaray railway tube tunnel is the world's deepest immersed tube tunnel with 60m undersea depth. The tunnel has 1.4km length with 13 segments. The tunnel is monitored with 2 strong motion accelerometers in each segment, 26 in total. Once the EEW signal is received, the monitoring system is activated and the recording ground motion parameters are calculated in real-time. Depending on the exceedance of threshold levels, further actions are taken such as reducing the train speed, stopping the train before entering the tunnel etc. In Istanbul, there are also on-site EEW system applied in several high

  3. Solar array experiments on the SPHINX satellite. [Space Plasma High voltage INteraction eXperiment satellite

    NASA Technical Reports Server (NTRS)

    Stevens, N. J.

    1974-01-01

    The Space Plasma, High Voltage Interaction Experiment (SPHINX) is the name given to an auxiliary payload satellite scheduled to be launched in January 1974. The principal experiments carried on this satellite are specifically designed to obtain the engineering data on the interaction of high voltage systems with the space plasma. The classes of experiments are solar array segments, insulators, insulators with pin holes and conductors. The satellite is also carrying experiments to obtain flight data on three new solar array configurations: the edge illuminated-multijunction cells, the teflon encased cells, and the violet cells.

  4. Evaluation of EMEP SOx emissions with OMI SO2 retrievals using WRF-CMAQ modeling system for Turkey

    NASA Astrophysics Data System (ADS)

    Abdi, Amirhossein; Kaynak Tezel, Burcak

    2016-04-01

    Sulfur dioxide is (SO2) is an atmospheric pollutant and has anthropogenic sources such as coal combustion at power plants and industrial facilities, industrial processes, and high sulfur containing fuel use by locomotives, large ships, and non-road equipment. Satellite retrievals indicated increase in SOx concentrations in Turkey, especially regions with coal power plants in the recent years. In this study, EMEP SOx emissions are evaluated for Turkey with OMI SO2 retrievals. Firstly, the spatial distribution of EMEP SOx emissions are compared with OMI SO2 retrievals and high emission regions are determined. A detailed analysis for point source and industrial emissions are performed and whether the effect of residential combustion of coal can be observed is investigated. Secondly, SO2 concentrations for one winter and one summer month in 2012 are simulated using a regional air quality modelling system for investigating the effect of different sources such as residential heating and energy production from coal combustion. WRF 3.7.1 is used for simulating the meteorology and CMAQ 5.0.2 is used to obtain atmospheric concentrations over a domain that covers Turkey with a spatial resolution of 10 km. The SO2 concentrations simulated using CMAQ are compared with OMI SO2 retrievals. This comparison will determine the similarities and discrepancies in the emission inventories. The comparison of satellite retrievals and with model simulations helps to assess the emission inventory reliability, and decreasing the uncertainty of these inventories.

  5. a Survey of Landnet Sites Focusing on Tuz GÖLÜ Salt Lake, Turkey

    NASA Astrophysics Data System (ADS)

    Gürbüz, S. Z.; Özen, H.; Chander, G.

    2012-07-01

    Radiometric calibration is critical to ensure the accuracy, veracity, continuity and reliability of satellite data measured from multiple sensors and platforms, and is thus recognized as a key activity by all satellite operators. For imaging sensors, vicarious methods using natural targets (such as salt lakes, deserts, or flatlands that are well-characterized and preferably temporally and spatially stable) as a reference are similarly well established. However, while selecting a target site, it is important that its quality and location are selected to minimize sources of uncertainty for any given sensor. To maximize the benefit from limited resources and minimize the impact on satellite operators, the Infrared Visible Optical Sensor (IVOS) sub-group of Committee on Earth Observation Satellites (CEOS) Working Group on Calibration and Validation (WGCV) has selected a few, well-characterized, regularly instrumented target sites, which have since become known as LANDNET sites. Currently, there are eight LANDNET sites: 1) Dome C, Antarctica; 2) Dunhuang, China, Asia; 3) Lspec Frenchman Flat, NV, USA, North America; 4) Ivanpah, NV/CA, USA, North America; 5) La Crau, France, Europe; 6) Negev, Southern Israel, Asia; 7) Railroad Valley Playa, NV, USA, North America; 8) Tuz Gölü, Central Anatolia, Turkey, Asia. This work summarizes the key characteristics, and areas of application of each of the LANDNET sites, especially that of Tuz Gölü, to guide and inform researchers on site selection, and increase international awareness and collaboration in this field. Additionally, detailed information about the Tuz Gölü, Turkey test site is provided, including geographical characteristics, spatial uniformity qualities, and opportunities for international researchers to conduct experiments and measurements. Practical, technical, and logistical experience gained through the international field campaigns organized over the last few years at Tuz Gölü is also shared in detail.

  6. Solar power satellite, system definition study. Part 2, volume 3: SPS satellite systems

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The differences in approach to solar energy conversion by solar cells and thermal engine systems are examined. Systems requirements for the solar power satellite (SPS) are given along with a description of the primary subsystems. Trades leading to exact configuration selection, for example, selection of the Rankine cycle operating temperatures are explained, and two satellite configurations are discussed.

  7. Satellite broadcasting in Europe

    NASA Astrophysics Data System (ADS)

    Bartholome, P.

    1984-05-01

    Three main communications services are recognized by the International Telecommunications Union: the Fixed Service, the Mobile Service and the Broadcasting Service. In Europe, EUTELSAT has just begun to exploit the first ECS satellite. The ESA-launched satellite was originally designed to provide an international public telecommunication service, however, the satellite will be used now almost exclusively for TV program distribution, while a second ECS satellite will be used for telephony. Despite plans for the launch of a third, countries in Europe are looking to other organizations such as INTELSAT for greater satellite capacity. Other organizations include Unisat, DFS/Copernicus, GDL, and Videosat. Both satellite and cable networks will increase the program-viewing audience, thus encouraging plans for a pan-European television service intended for an international audience. Although the combination of cable networks and distribution satellites looks promising, high-power broadcasting satellites will play an important role because of flexibility and additional program distribution.

  8. Stereo Measurements from Satellites

    NASA Technical Reports Server (NTRS)

    Adler, R.

    1982-01-01

    The papers in this presentation include: 1) 'Stereographic Observations from Geosynchronous Satellites: An Important New Tool for the Atmospheric Sciences'; 2) 'Thunderstorm Cloud Top Ascent Rates Determined from Stereoscopic Satellite Observations'; 3) 'Artificial Stereo Presentation of Meteorological Data Fields'.

  9. Antioxidant status of turkey breast meat and blood after feeding a diet enriched with histidine.

    PubMed

    Kopec, W; Wiliczkiewicz, A; Jamroz, D; Biazik, E; Pudlo, A; Hikawczuk, T; Skiba, T; Korzeniowska, M

    2016-01-01

    The objective of this study was to investigate the effects of 1) spray dried blood cells rich in histidine and 2) pure histidine added to feed on the antioxidant status and concentration of carnosine related components in the blood and breast meat of female turkeys. The experiment was performed on 168 Big7 turkey females randomly assigned to 3 dietary treatments: control; control with the addition of 0.18% L-histidine (His); and control with the addition of spray dried blood cells (SDBC). Birds were raised for 103 d on a floor with sawdust litter, with drinking water and feed ad libitum. The antioxidant status of blood plasma and breast muscle was analyzed by ferric reducing ability (FRAP) and by 2,2-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radicals scavenging ability. The activity of antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) was analyzed in the blood and breast meat, with the content of carnosine and anserine quantified by HPLC. Proximate analysis as well as amino acid profiling were carried out for the feed and breast muscles. Growth performance parameters also were calculated. Histidine supplementation of the turkey diet resulted in increased DPPH radical scavenging capacity in the breast muscles and blood, but did not result in higher histidine dipeptide concentrations. The enzymatic antioxidant system of turkey blood was affected by the diet with SDBC. In the plasma, the SDBC addition increased both SOD and GPx activity, and decreased GPx activity in the erythrocytes. Feeding turkeys with an SDBC containing diet increased BW and the content of isoleucine and valine in breast muscles. PMID:26574038

  10. Effect of dexamethasone on bacteriostatic activity of turkey monocytes and implications for food safety.

    PubMed

    Huff, G R; Huff, W E; Rath, N C

    2015-08-15

    Stress has been shown to affect the immune system of turkeys making them more susceptible to bacterial infections. Five-week-old male and female turkeys were treated with 3 intra-muscular injections of dexamethasone (Dex) at 0, 0.5 and 2.0mg/kg body weight. Twenty-four hours after the third injection birds were bled and white blood cell (WBC) differentials and bacteriostatic activity of monocytes were measured. Dex at both 0.5 and 2.0mg/kg decreased phagocytic activity in females only. Bacteriostatic activity was decreased at both concentrations of Dex at 8 and 16 h post-infection in both sexes and was lower in males as compared to females. Total WBC counts were increased in females at both concentrations of Dex whereas male total WBC counts were unaffected. Both males and females had an increase in the heterophil to lymphocyte ratio. Within the same study, replicate pens of turkeys were challenged with intra-air sac inoculation of 100 cfu of Escherichia coli. Isolation of E. coli was significantly increased by both Dex and E. coli challenge, but there were no differences between sexes. These results suggest that stress can compromise the bacteriostatic activity of turkey monocytes and increase bacterial colonization of blood and tissues, potentially affecting food safety. PMID:26099808

  11. Volcanic and earthquake hazards at eastern Turkey volcanoes investigated by InSAR

    NASA Astrophysics Data System (ADS)

    Bathke, H.; Walter, T. R.

    2010-12-01

    Volcanoes of eastern Turkey have been historically active and are located in a poorly understood tectonic system with abundant faults and fissures. Mt Ararat and Tendürek, for instance, are located in a pull apart basin, and have been affected by significant tectonic earthquakes reaching magnitudes of 7.4 in 1840 and again in 1976, causing 10,000 and 5,000 fatalities, respectively. Today's tectonic and volcanic deformation processed remained to be elaborated, however. Here we report on a radar interferometric study using SAR images acquired by the satellites ERS-1, ERS-2 and ENVISAT in ascending and descending orbits. We create interferograms and combine them into a time series, which now allow us to investigate temporal deformation pattern of the ground at unprecedented spatial detail. Although the volcanoes have not been erupting since 160 years and are considered to be dormant, we find various localized but evident deformation processes. Our investigation suggest both processes, earthquakes as well as volcanic activity, to be responsible for the observed deformation. Thus the presented satellite radar data analysis contributes to process understanding and the associated hazards in eastern Turkey.

  12. Analysis of long term trends of precipitation estimates acquired using radar network in Turkey

    NASA Astrophysics Data System (ADS)

    Tugrul Yilmaz, M.; Yucel, Ismail; Kamil Yilmaz, Koray

    2016-04-01

    Precipitation estimates, a vital input in many hydrological and agricultural studies, can be obtained using many different platforms (ground station-, radar-, model-, satellite-based). Satellite- and model-based estimates are spatially continuous datasets, however they lack the high resolution information many applications often require. Station-based values are actual precipitation observations, however they suffer from their nature that they are point data. These datasets may be interpolated however such end-products may have large errors over remote locations with different climate/topography/etc than the areas stations are installed. Radars have the particular advantage of having high spatial resolution information over land even though accuracy of radar-based precipitation estimates depends on the Z-R relationship, mountain blockage, target distance from the radar, spurious echoes resulting from anomalous propagation of the radar beam, bright band contamination and ground clutter. A viable method to obtain spatially and temporally high resolution consistent precipitation information is merging radar and station data to take advantage of each retrieval platform. An optimally merged product is particularly important in Turkey where complex topography exerts strong controls on the precipitation regime and in turn hampers observation efforts. There are currently 10 (additional 7 are planned) weather radars over Turkey obtaining precipitation information since 2007. This study aims to optimally merge radar precipitation data with station based observations to introduce a station-radar blended precipitation product. This study was supported by TUBITAK fund # 114Y676.

  13. Building technological capability within satellite programs in developing countries

    NASA Astrophysics Data System (ADS)

    Wood, Danielle; Weigel, Annalisa

    2011-12-01

    This paper explores the process of building technological capability in government-led satellite programs within developing countries. The key message is that these satellite programs can learn useful lessons from literature in the international development community. These lessons are relevant to emerging satellite programs that leverage international partnerships in order to establish local capability to design, build and operate satellites. Countries with such programs include Algeria, Nigeria, Turkey, Malaysia and the United Arab Emirates. The paper first provides background knowledge about space activity in developing countries, and then explores the nuances of the lessons coming from the international development literature. Developing countries are concerned with satellite technology because satellites provide useful services in the areas of earth observation, communication, navigation and science. Most developing countries access satellite services through indirect means such as sharing data with foreign organizations. More countries, however, are seeking opportunities to develop satellite technology locally. There are objective, technically driven motivations for developing countries to invest in satellite technology, despite rich debate on this topic. The paper provides a framework to understand technical motivations for investment in satellite services, hardware, expertise and infrastructure in both short and long term. If a country decides to pursue such investments they face a common set of strategic decisions at the levels of their satellite program, their national context and their international relationships. Analysis of past projects shows that countries have chosen diverse strategies to address these strategic decisions and grow in technological capability. What is similar about the historical examples is that many countries choose to leverage international partnerships as part of their growth process. There are also historical examples from

  14. Magnetospheres: Jupiter, Satellite Interactions

    NASA Astrophysics Data System (ADS)

    Neubauer, F.; Murdin, P.

    2000-11-01

    Most of the satellites of Jupiter, notably the large Galilean satellites Io, Europa, Ganymede and Callisto (see JUPITER: SATELLITES), orbit deep inside the magnetosphere of Jupiter (see JUPITER: MAGNETOSPHERE) and are therefore immersed in the flow of magnetospheric plasma (made of a mixture of electrons and ions) and subjected to an interaction with the strong Jovian magnetic field. These intera...

  15. [Theme Issue: Communications Satellites.

    ERIC Educational Resources Information Center

    Howkins, John, Ed.

    1976-01-01

    One section of this journal is devoted to issues involving broadcast satellites. Separate articles discuss the need for international planning of satellite broadcasting, decisions made at the 1971 World Administrative Radio Conference for Space Telecommunications, potential problems in satellite broadcasting, a series of proposals drawn up by the…

  16. Risk and Career Choice: Evidence from Turkey

    ERIC Educational Resources Information Center

    Caner, Asena; Okten, Cagla

    2010-01-01

    In this paper, we examine the college major choice decision in a risk and return framework using university entrance exam data from Turkey. Specifically we focus on the choice between majors with low income risk such as education and health and others with riskier income streams. We use a unique dataset that allows us to control for the choice set…

  17. Infant Feeding Practices in Central Anatolia, Turkey

    ERIC Educational Resources Information Center

    Sanlier, Nevin; Unusan, Nurhan

    2009-01-01

    Infant feeding decisions are some of the most important choices parents make. Breast milk or formula is the first decision made in infant feeding. Complementary feeding is common among very young children in Turkey. Therefore, the aim of this research is to focus on the introduction of solid foods, and to determine the relationship between…

  18. The First ETV Project of Turkey.

    ERIC Educational Resources Information Center

    Eskisehir Academy of Economic and Commercial Sciences (Turkey). Inst. of Educational Television.

    The success of a small-scale, closed circuit educational television project run at the Academy of Economic and Commercial Sciences in Eskisehir, Turkey has led to the expansion of the experiment. The expanded project will offer services to other academies, demonstrate the effective use of educational television, and serve as an integral part of…

  19. Globalization and English Language Policy in Turkey

    ERIC Educational Resources Information Center

    Kirkgoz, Yasemin

    2009-01-01

    It is widely acknowledged that globalization has made a considerable impact on multidimensional aspects of human life including the language policies of many countries. This article examines the adjustment of Turkey's language policy in response to the global influence of English at different levels of Turkish national education, including its…

  20. The Determinants of Student Achievement in Turkey

    ERIC Educational Resources Information Center

    Dincer, M. A.; Uysal, G.

    2010-01-01

    Recent achievement test results show that Turkish students have been performing poorly compared to students from other countries. Using science literacy results from the PISA 2006 survey, we aim to measure the determinants of student achievement in Turkey within the education production function framework. We find that program types have large…

  1. MAXIMIZING THE FERTILITY POTENTIAL OF TURKEY SEMEN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Turkeys are the only commercial poultry species completely dependent upon artificial insemination for fertile egg production. Although time and labor-intensive, artificial insemination has proven to be a key strategy for achieving rapid genetic improvements in economically important traits such as g...

  2. Clay Corner: Light up a Turkey.

    ERIC Educational Resources Information Center

    Hiller, Peter

    1998-01-01

    Presents two activities that enable students to work with clay: a tile project and turkey candle-holders. Explains that before students actually create their own projects, they get an opportunity to experience the clay itself. Asserts that the new vocabulary, unusual equipment, and intriguing techniques make ceramics a motivating activity. (CMK)

  3. Cultural Studies in Turkey: Education and Practice

    ERIC Educational Resources Information Center

    Pultar, Gonul; Kirtunc, Ayse Lahur

    2004-01-01

    In this essay, the authors aim at contributing to the debate on "International Perspectives on Cultural Studies in/and Education" by presenting a perspective from Turkey, and problematizing the issues that are encountered in the country in the instruction and practice of cultural studies. They start with a brief survey of the Ege University…

  4. Fundamentalist Bedfellows: Political Creationism in Turkey.

    ERIC Educational Resources Information Center

    Shapiro, Arthur M.

    1999-01-01

    Defines Islamic creationism and anti-evolutionism in Turkey, provides information about political and cultural changes starting from the 1920s, and discusses Islamic movements at this time. Presents examples of politicians' approaches to this issue and points out the effects of Christian creationism and the Institute for Creation Research (ICR) on…

  5. Vocational and Technical Education Reform in Turkey

    ERIC Educational Resources Information Center

    Kilic, Abdurrahman

    2006-01-01

    Turkey is a country where individual rights and freedom of people are improving. It is known that a free market economy is in its infancy. There is a strong relationship between developed human resources and the production sector. In this sense, vocational and technical education is very important. It cannot be said that the efforts for…

  6. Transition to Family Practice in Turkey

    ERIC Educational Resources Information Center

    Gunes, Evrim Didem; Yaman, Hakan

    2008-01-01

    Introduction: Turkey's primary health care (PHC) system was established in the beginning of the 1960s and provides preventive and curative basic medical services to the population. This article describes the experience of the Turkish health system, as it tries to adapt to the European health system. It describes the current organization of primary…

  7. Geography, GIS and Employability in Turkey

    ERIC Educational Resources Information Center

    Seremet, Mehmet; Chalkley, Brian

    2016-01-01

    Although higher education in Turkey does not have especially well-advanced systems and resources for addressing graduate employability, two developments are making it particularly important for Turkish geography departments to give increased priority to this agenda. One is the country's new Higher Education Qualifications Framework and the other…

  8. Internet Censorship in Turkey: University Students' Opinions

    ERIC Educational Resources Information Center

    Ozkan, Hasan; Arikan, Arda

    2009-01-01

    The aim of this paper is to study university students' opinions toward online censorship with references to their socio-political and economic variables. Considering the upwards trend and the increasing number of online restrictions in Turkey, the opinions of university students (n=138) are thought to give significant findings. The questionnaire…

  9. Extensive Quaternary glaciations in eastern Turkey

    NASA Astrophysics Data System (ADS)

    Yeşilyurt, Serdar; Akçar, Naki; Doǧan, Uǧur; Yavuz, Vural; Ivy-Ochs, Susan; Vockenhuber, Christof; Schlunegger, Fritz; Schlüchter, Christian

    2016-04-01

    During cold periods in the Quaternary, global ice volume increased and as a result valley glaciers advanced and the vice versa occurred during the warm periods. Quaternary glacier fluctuations had been also recorded in the Turkish mountains. Recently, the chronology of Late Quaternary advances in the northern and western Turkish mountains was reconstructed by surface exposure dating. However, these advances in the eastern Turkey are not dated yet. In this study, we investigated paleoglaciations in Kavuşşahap Mountains, which is located to the south of Lake Van in eastern Turkey. These mountains are one of the extensively glaciated areas in Turkey. Glacial activity is evidenced by more than 20 U-shaped valleys. For instance, one of the prominent and well-preserved glacial landscapes of Turkey is situated in the Narlıca valley system. Lateral and terminal moraines in the valley system indicate more than 10 glacial advances. To build their chronology, 39 erratic carbonaceous boulders were sampled for surface exposure dating with cosmogenic 36Cl. We also reconstructed the ice margin reconstruction of the Narlıca paleoglacier using the accumulation area ratio and area-altitude balance ratio approaches. We estimated an equilibrium line altitude (ELA) of ca. 2900 m above sea level based on the maximum ice extend, which implied ca. 800 m decrease in the ELA during the Late Quaternary in comparison to the lower bound of the modern ELA estimate. The first results of the surface exposure dating will be presented.

  10. Global attention to Turkey due to desertification.

    PubMed

    Camci Cetin, S; Karaca, A; Haktanir, K; Yildiz, H

    2007-05-01

    Desertification has recognized as an environmental problem by many international organizations such as UN, NATO and FAO. Desertification in Turkey is generally caused by incorrect land use, excessive grazing, forest fires, urbanization, industry, genetic erosion, soil erosion, salinization, and uncontrolled wild type plants picking. Due to anthropogenic destruction of forest, steppe flora gradually became dominant in Anatolia. In terms of biodiversity, Turkey has a significant importance in Europe and Middle East. Nine thousands plant species naturally grown in Turkey, one third of them are endemic. Also, endemic species of vertebrates, thrive in the lakes and marshy areas. The studies of modelling simulation of vegetation on the effects of Mediterranean climate during the Roman Classical period by using vegetation history showed that, in 2000 years BP, Mediterranean countries were more humid than today. Turkey is a special place on the global concern in terms of desertification because of biodiversity, agricultural potential, high population, social and economical structure, topographical factors and strategic regional location. Communication among scientists, decision makers and international non-profit organizations must be improved. PMID:17057981

  11. Tylosin depletion in edible tissues of turkeys.

    PubMed

    Montesissa, C; De Liguoro, M; Santi, A; Capolongo, F; Biancotto, G

    1999-10-01

    The depletion of tylosin residues in edible turkey tissues was followed after 3 days of administration of tylosin tartrate at 500 mg l-1 in drinking water, to 30 turkeys. Immediately after the end of the treatment (day 0) and at day 1, 3, 5 and 10 of withdrawal, six turkeys (three males and three females) per time were sacrificed and samples of edible tissues were collected. Tissue homogenates were extracted, purified and analysed by HPLC according to a method previously published for the analysis of tylosin residues in pig tissues. In all tissues, tylosin residues were already below the detection limits of 50 micrograms kg-1 at time zero. However, in several samples of tissues (skin + fat, liver, kidney, muscle), from the six turkeys sacrificed at that time, one peak corresponding to an unknown tylosin equivalent was detected at measurable concentrations. The identification of this unknown compound was performed by LC-MS/MS analysis of the extracts from incurred samples. The mass fragmentation of the compound was consistent with the structure of tylosin D (the alcoholic derivative of tylosin A), the major metabolite of tylosin previously recovered and identified in tissues and/or excreta from treated chickens, cattle and pigs. PMID:10755131

  12. Factors Influencing Teaching Choice in Turkey

    ERIC Educational Resources Information Center

    Kilinc, Ahmet; Watt, Helen M. G.; Richardson, Paul W.

    2012-01-01

    Why choose to become a teacher in Turkey? The authors examined motivations and perceptions among preservice teachers (N = 1577) encompassing early childhood, primary and secondary education. The Factors Influencing Teaching Choice (FIT-Choice) instrument was translated into Turkish and its construct validity and reliability assessed. Altruistic…

  13. PREVALENCE OF ARCOBACTER IN COMMERCIAL TURKEY PRODUCTION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of Arcobacter in live turkeys was determined for six Midwestern commercial flocks. In the first study (summer 2003), cloacal (n = 298) and feather swabs (n = 75), cecal (n = 70), and crop (n = 50) contents, drinker water (n = 46), and environmental (n = 25) samples were monitored. I...

  14. Effects of high-orbit spaceflight on signaling cascades and apoptosis in immune cells from mice flied on board the BION-M1 satellite

    NASA Astrophysics Data System (ADS)

    Novoselova, Elena; Shenkman, Boris; Lunin, Sergey; Parfenyuk, Svetlana; Novoselova, Tatyana; Fesenko, Eugeny

    The study was designed to evaluate immune cell activity in male C57bl mice after a 30-day high-orbit spaceflight (550 km, higher than conventional manned spaceflights) on board the BION-M1 satellite (Roskosmos Program, Russia). For the present study, thymus, spleens and plasma samples were collected from mice 12 h after landing and, additionally, 7 days subsequently. Assessing the activity of NF-kappaB signaling cascade by measuring Rel A (p65) protein phosphorylation in splenic lymphocytes, we showed that the NF-kappaB activity was significantly increased at 12 h after landing. Contrariwise, one week after landing, the NF-kappaB activity was markedly decreased, even below to the control values. Interestingly, after landing there were no significant changes in SAPK/JNK cascade activity in splenic lymphocytes as well as in the expression of transcription factor IRF3 in thymus cells. To assess the apoptosis status in thymus lymphocytes, levels of p53 protein and its phosphorylated form were measured in thymic lymphocytes. It is known that p53 plays an important role in the cellular response to DNA damage, genomic aberrations, and other characteristic of apoptosis. The results showed that the high-orbit spaceflight environment caused some increase in level of p53 protein, but most notably, activated phosphorylated form of p53 protein. Calculated ratio of active and inactive forms of the protein (ph-p53/p53) 12 h after landing increased by more than 2-fold, indicating the apparent induction of apoptosis in thymus cells. Interestingly, 7 days after the landing, this ratio was not restored, but rather increased: the specified ratio was 4 times higher as compared to the ground-based control. We can conclude that response to the prolonged high-orbit spaceflight is not like the classic "stress response", which is usually observed under various stressful factors. It is known that the stress response is surely accompanied by increased SAPK/JNK cascade activity as well as the

  15. Survey: National Environmental Satellite Service

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The national Environmental Satellite Service (NESS) receives data at periodic intervals from satellites of the Synchronous Meteorological Satellite/Geostationary Operational Environmental Satellite series and from the Improved TIROS (Television Infrared Observational Satellite) Operational Satellite. Within the conterminous United States, direct readout and processed products are distributed to users over facsimile networks from a central processing and data distribution facility. In addition, the NESS Satellite Field Stations analyze, interpret, and distribute processed geostationary satellite products to regional weather service activities.

  16. Digital satellite communications

    NASA Astrophysics Data System (ADS)

    Ha, T. T.

    1986-06-01

    The use of satellite communications in point-to-multipoint transmission of data is studied. The theory, systems, and equipment for satellite communications are described. The topics of satellite orbits, satellite construction, earth station equipment, and the analysis of the satellite link are discussed. Different types of digital modulation for carrier transmission, and techniques for enhancing the transmission capacity, such as digital speech interpolation and demand assignment, are examined. Techniques and equipment for performing the multiple access-broadcasting functions including FDMA, TDMA, DAMA, CDMA, and random access are considered.

  17. Fundamentals of satellite navigation

    NASA Astrophysics Data System (ADS)

    Stiller, A. H.

    The basic operating principles and capabilities of conventional and satellite-based navigation systems for air, sea, and land vehicles are reviewed and illustrated with diagrams. Consideration is given to autonomous onboard systems; systems based on visible or radio beacons; the Transit, Cicada, Navstar-GPS, and Glonass satellite systems; the physical laws and parameters of satellite motion; the definition of time in satellite systems; and the content of the demodulated GPS data signal. The GPS and Glonass data format frames are presented graphically, and tables listing the GPS and Glonass satellites, their technical characteristics, and the (past or scheduled) launch dates are provided.

  18. TSS Satellite Overview

    NASA Technical Reports Server (NTRS)

    Manarini, G.

    1985-01-01

    The responsibilities of NASA and PSN/CNR in the tethered satellite system cooperative program are listed and PSN/CNR-AIT system support and technologies studies are summarized. Results are given for investigations of active vs. passive satellite trade offs; analysis of alternative maneuvers; satellite attitude and position determination analysis failure modes analysis; moveable boom dynamic analysis; double tethered satellite system; and thermo/dynamic analysis for 100 km to 120 km altitude range. Objectives for the space plasma science mission and its applications are outlined and the TSS satellite configuration is highlighted. Programmatic aspects are included.

  19. Homosexuality and police terror in Turkey.

    PubMed

    Yuzgun, A

    1993-01-01

    Being a way of sexual living as old as human history, homosexuality occupies an interesting place in the life of the Turkish people of the Republic of Turkey. This has been so since the days of the glorious Ottoman Empire. In the year 1987, instead of investigating the roots of homosexuality, the pressing need has become to present a particular view of homosexuality in Turkey today. To be more specific, there is a need to explain the problems of Turkish homosexuals and suggest certain vital solutions. Our country is constantly endeavoring to become "westernized" and it is claimed that steps are being taken toward that modernization. Despite this fact, homosexuals are confronted with such great problems that it is not difficult to justify those who say that there is no democracy in Turkey. I will try to explain these problems with documentary evidence and without exaggeration. In doing so, I shall make use of new material in my book, published under the title of Homosexuality in Turkey: Yesterday, Today. Beginning in March of 1986, we compiled a list of the attitudes of the police toward gays, involving pressure and cruelty that can be qualified as torture. Despite this situation, instead of being more democratic and humane, in April 1987 the police force employed terror tactics against homosexuals in Istanbul. This was "the straw that broke the camel's back." Soon after this act of oppression, 18 gays, acting on our suggestions, sued the police for the first time. They then submitted a petition to the Attorney-General and later launched a hunger strike in Taksim Square. These represent movements of importance in the political history of Turkey. From now on homosexuals, too, will have the right to speak out in political affairs. PMID:8505535

  20. Toward a phenology network in Turkey

    NASA Astrophysics Data System (ADS)

    Dalfes, H. N.; Ülgen, H.; Zeydanli, U.; Durak, A. T.

    2012-04-01

    All climate projections indicate that drastic changes are to occur in the Mediterranean Basin and Southwestern Asia. Detailed studies also foresee strong patterns of change in seasonality for most climate fields all across the country, threatening Turkey's rich biodiversity and diverse ecosystems already in trouble due to massive land use changes and careless resource extraction projects. It is therefore obvious that climate impact studies can benefit from detailed and continuous monitoring of relationships between climate and natural systems. Recently started efforts to build a phenology network for Turkey will hopefully constitute a component of a more comprehensive ecological observation infrastructure. The Phenology Network of Turkey Project saw its debut as a joint initiative of an academic institution (Istanbul Technical University) and a research NGO (Nature Conservation Center). It has been decided from the very beginning to rely a much as possible on Internet technologies (provided by the National High Performance Computing Center of Turkey). The effort is also inspired by and collaborates with already established networks in general and USA National Phenology Network in particular. Many protocols, instructional materials and Nature's Notebook application has been barrowed from the USA NPN. The project has been designed from the start as a two-faceted effort: an infrastructure to accumulate/provide useful data to climate/ecosystem research communities and a 'citizen science' project to raise nature and climate change awareness among all components of the society in Turkey in general and secondary education teachers and students in particular. It has been opted to start by gathering plant phenological data. A set with 20 plant species has been designed to serve as a countrywide 'calibration set'. It is also anticipated to salvage and extend as much of possible historical animal (especially bird and butterfly) observations.

  1. Nephrology, dialysis and transplantation in Turkey.

    PubMed

    Erek, Ekrem; Süleymanlar, Gültekin; Serdengeçti, Kamil

    2002-12-01

    The establishment of the Turkish Society of Nephrology (TSN) in 1970 coincided with that of many western European nephrology societies. The TSN organized the 15th ERA-EDTA Congress in Istanbul in 1978, earlier than many European Countries, and currently has 286 active members. At present, Turkey has 161 nephrologists, which equals 2.5 nephrologists per million population (p.m.p.). The number of original articles submitted by Turkish authors to the journal Nephrology Dialysis Transplantation ranks 7th-8th amongst total submissions to the journal. Turkey also ranks 2nd-4th in the number of abstracts submitted to recent ERA-EDTA Congresses. With 18 063 patients undergoing intermittent haemodialysis treatment in 348 dialysis centres, Turkey has the 5th largest chronic haemodialysis patient population among European countries. In addition, 1903 patients are currently undergoing continuous ambulatory peritoneal dialysis. However, with a total of 4693 renal transplants since 1975, of which only 21.3% were of cadaveric origin, Turkey lags considerably behind other European countries in renal transplantation. In Turkey, the prevalence and incidence of renal replacement therapy (RRT) are at present 358 and 52 p.m.p. respectively, and the expansion rate of the RRT stock is 17% (HD 18.5%, CAPD 6%, and transplantation 1.7%). The yearly gross mortality rate of the total RRT population is 9.4%. The present priorities of the Turkish nephrological community include high-standard research activity and long-term, prospective clinical and epidemiological studies, an increase in the total number and percentage of cadaveric transplants, further improvement of the quality and cost-effectiveness of RRT, and finally the further development of scientific and educational collaboration with the world nephrological community. PMID:12454217

  2. Satellite altitude determination uncertainties

    NASA Technical Reports Server (NTRS)

    Siry, J. W.

    1971-01-01

    Satellite altitude determination uncertainties are discussed from the standpoint of the GEOS-C satellite. GEOS-C will be tracked by a number of the conventional satellite tracking systems, as well as by two advanced systems; a satellite-to-satellite tracking system and lasers capable of decimeter accuracies which are being developed in connection with the Goddard Earth and Ocean Dynamics Applications program. The discussion is organized in terms of a specific type of GEOS-C orbit which would satisfy a number of scientific objectives including the study of the gravitational field by means of both the altimeter and the satellite-to-satellite tracking system, studies of tides, and the Gulf Stream meanders.

  3. Dimensioning of Aeronautical Satellite Services

    NASA Astrophysics Data System (ADS)

    Holzbock, M.; Jahn, A.; Werner, M.

    2002-01-01

    This paper will provide a generalised baseline for a systematic AirCom design process and address in particular the dimensioning of satellite systems for aeronautical services. These services will roll out soon in medium- and long-haul aircraft. The offered services will range from low rate telephony, internet access, and streaming applications for video and audio. The aggregate bit rates on up- and downlink will certainly be statistically time-dependent and asymmetric in forward and backward direction. A tool will be described that is able to model this traffic. Furthermore the dimensioning of satellite constellations can be done. Due to the stochastic nature of the traffic, multi-service models for the traffic generation of different services will be described. Furthermore, the traffic will be affected by the available bit rate and shaping or blocking will equalize the peak loads. If fleets with many aircraft are considered, aeronautical traffic models must be based on actual aircraft routes, flight schedules, location and time of day, as well as seats per aircraft and type of aircraft (charter, business etc.). The regionally distributed traffic has to be served by several satellites and appropriate sharing of the serving satellites may spread the traffic in hot zones and yield a better load distribution. When aeronautical services will spread out, the capacity demand will grow quickly and the capacity of existing Ku-band GEO satellites will soon be exceeded. Changing to higher frequency bands will provide large spectrum portions and smaller spotbeams will allow better frequency reuse. Even constellations with non-geostationary satellites could be re-advent to serve better the higher latitude regions. Then, another mobility component for the fast changing satellite topology need to be addressed, and routing issues of the traffic must be considered. The paper will describe solutions for the mapping of satellites and traffic demand as well as routing algorithms

  4. The influence of phytoncides on the immune system of broiler chickens and turkeys

    PubMed Central

    Śmiałek, Marcin; Tykałowski, Bartłomiej; Pestka, Daria; Stenzel, Tomasz

    2015-01-01

    The aim of our study was to investigate the influence of adiSalmoSOL PF dietary supplement, given for 3 days in drinking water, on selected parameters of cell-mediated (Experiment I) and humoral (Experiment II) immunity in chicken and turkey broilers. In Experiment I, birds were randomly divided into two groups of 10 birds each. Group 1 comprised control turkeys or chickens, whereas group 2 birds were administered adiSalmoSOLPF. In Experiment II, a total of 69 chickens were divided into three groups (1-3) of 23 birds each. At the age of 25 days, group 1 was given adiSalmoSOLPF. Birds from groups 1-3 were vaccinated at 28 days of age. Group 2 was given adiSalmoSOLPF after vaccination. In Experiment I, a significant increase in percentages of CD4 + T lymphocytes in the bursa of Fabricius, cecal tonsils and spleen, CD8 + T lymphocytes in the thymus and spleen, CD4 + CD8 + T lymphocytes in the bursa of Fabricius and ileal mucosa and IgM + B lymphocyte in the ileal mucosa were observed in group 2 chickens. In Experiment I, a significant increase in percentages of CD4 + T lymphocytes in the thymus and spleen, CD8+ T lymphocytes in the cecal tonsils and blood, and CD4 + CD8 + T lymphocytes in the thymus and ileal mucosa was recorded in group 2 turkeys. No differences in percentages of IgM + B lymphocytes were observed between turkey groups. In Experiment II, the highest post-vaccination titers of anti-IB antibodies were observed in group 2, but it was not statistically significant. The results of our study indicate that adiSalmoSOLPF showed immunomodulatory activity in chickens and turkeys. PMID:26648771

  5. Skynet satellite electron precharging experiments

    NASA Technical Reports Server (NTRS)

    Vanlint, V. A. J.; Fromme, D. A.; Stettner, R.

    1979-01-01

    Large surface areas (approximately 1 sq m) of the Skynet I qualification model satellite were exposed to the environments of a flux of monoenergetic electrons and pulsed high-intensity X-ray photons from an exploding-wire-radiator source, separately and simultaneously. Experiments were performed with both the cylindrical solar cell panels and the end thermal blanket exposed to these environments. The satellite was instrumented with fiber-optics isolated fast-response sensors capable of sensing and recording the time-varying electric fields and surface currents on the satellite. Spontaneous discharges of the two surfaces were characterized prior to measurements of the interaction of the system-generated electromagnetic pulse from the X-ray photon burst with the electron precharged surfaces. A two-dimensional self-consistent finite difference computer code was used to predict the currents on the Skynet both with and without precharging of the thermal-blanket. These calculations, which used an thermal-blanket voltage profile, predicted a factor of 2 increase in satellite exterior axial currents.

  6. Differential ex vivo responses of primary leukocytes from turkey pedigree lines to Salmonella Heidelberg.

    PubMed

    Potter, Tiffany D; Glover, Paige K; Evans, Nicholas P; Dalloul, Rami A

    2016-02-01

    Escalating product recalls as a consequence of Salmonella-contaminated poultry products have resulted in detrimental economic impacts in the poultry industry. One potential long-term alternative method to Salmonella prevention is genetic selection to improve innate resistance. This study evaluated the ex vivo effects of Salmonella Heidelberg (SH) on phagocytic and bactericidal leukocyte function in turkeys from six pedigree lines (A-F). Day-of-hatch poults (n = 48) were placed and raised in cages (2 birds/gender/genetic line/cage) to 35 d when heterophils and peripheral blood mononuclear cells (PBMCs) were extracted from males and females of each line. Cells were used in phagocytic and bactericidal assays to determine the ex vivo effects of SH on turkey leukocyte activity. Data were analyzed using the Fit Model platform in JMP Pro 10.0 (SAS Institute Inc.) with differences considered significant at P ≤ 0.05 and data reported as LS Means with SEM. Although genetic line had no significant effect on phagocytosis of SH by heterophils and PBMCs, cumulatively, female cells exhibited higher phagocytosis potential than those from males. The main effect of gender was significant on bactericidal activity of PBMCs when incubated at a 1:10 and 1:100 PBMC to SH ratio. Genetic line also had a significant effect on bactericidal activity of PBMCs with cells from line F exhibiting the best activity. These results suggest that gender had a marked cumulative effect on phagocytosis of SH by heterophils and PBMCs while both genetic line and gender had a prominent effect on bacterial killing of SH by turkey PBMCs. Once able to determine genetic markers associated with these immune responses to Salmonella, genetic selection for increased resistance may become feasible in turkeys. PMID:26706359

  7. Initial evaluation tests of Eagle-Picher Industries 9.0 ampere-hour nickel-cadmium spacecraft cells for the heat capacity mapping mission satellite and the stratospheric aerosol and gas experiment satellite

    NASA Technical Reports Server (NTRS)

    Harkness, J. D.

    1978-01-01

    The results of tests to insure that all cells put into the life cycle program are of high quality are reported. The tests consisted of the following: phenolptalein leak tests, internal short test, charge efficiency test, and overcharge tests. The results of tests for 10 cells are tabulated.

  8. Pineal concretions in turkey (Meleagris gallopavo) as a result of collagen-mediated calcification.

    PubMed

    Przybylska-Gornowicz, B; Lewczuk, B; Prusik, M; Bulc, M

    2009-04-01

    The intra-pineal calcification is a well-known phenomenon in mammals, however it is almost completely unknown in birds. The aim of the present work was to analyze morphology and genesis of the pineal concretions in the turkey. The studies were performed on the pineals collected from one-year-old turkeys (Meleagris gallopavo). In addition to standard morphological methods, the alizarin red S and potassium pyroantimonate methods were employed for localization of calcium at the light and electron microscopy level. In light microscopy, calcified concretions with diameters from 300 microm to 2 mm and quantities from 3 to 6 per gland were observed in all the examined pineals. They were stained red with alizarin S and showed the presence of collagen in Mallory's staining. Two types of cells were noted inside the concretion: polygonal and elongated ones. Using electron microscopy, three parts were distinguished within the calcification area. The peripheral part contained densely packed collagen fibrils, some elongated cells and numerous pyroantimonate precipitates demonstrating the presence of calcium ions. In the intermediate part, the fibrils were covered by almost continuous sheets of pyroantimonate precipitates and fused side by side. The central part showed an appearance of calcified hard tissue and contained some polygonal (osteocyte-like) cells. The obtained data demonstrated that the formation of the pineal concretions in the turkey is associated with the mineralization of collagen. This process is completely different from the mechanisms responsible for the formation of the concretions in the mammalian pineal. PMID:19224443

  9. Communication satellite applications

    NASA Astrophysics Data System (ADS)

    Pelton, Joseph N.

    The status and future of the technologies, numbers and services provided by communications satellites worldwide are explored. The evolution of Intelsat satellites and the associated earth terminals toward high-rate all-digital telephony, data, facsimile, videophone, videoconferencing and DBS capabilities are described. The capabilities, services and usage of the Intersputnik, Eutelsat, Arabsat and Palapa systems are also outlined. Domestic satellite communications by means of the Molniya, ANIK, Olympus, Intelsat and Palapa spacecraft are outlined, noting the fast growth of the market and the growing number of different satellite manufacturers. The technical, economic and service definition issues surrounding DBS systems are discussed, along with presently operating and planned maritime and aeronautical communications and positioning systems. Features of search and rescue and tracking, data, and relay satellite systems are summarized, and services offered or which will be offered by every existing or planned communication satellite worldwide are tabulated.

  10. Determinants of a quality wild turkey hunting season.

    PubMed

    Wynveen, Christopher J; Cavin, Drew A; Wright, Brett A; Hammitt, William E

    2005-07-01

    According to the National Wild Turkey Federation, there has been a 450% increase in the number of licensed wild turkey hunters since 1973. Unfortunately, there is a paucity of research articles focusing specifically on turkey hunting. Most human dimensions of wildlife research have focused on either deer or waterfowl hunting. In this study, dimensions of hunting quality, days a field, and harvest were examined among a sample of 739 Virginia fall turkey hunters. Quality of a hunting season, rather than a specific hunt, was examined. Principal components analysis (PCA) revealed five domains of attributes of a high-quality turkey-hunting season: wildlife interaction, education, being away, social interaction, and hunting skills. The domains of hunting quality revealed by the PCA are similar to domains found previously for spring turkey hunters as well as other types of hunters. Also examined were hunter perceptions of overall hunting quality, the number of days spent hunting turkeys during the fall season, and harvest success. For comparative purposes and agency needs, hunters were segmented into three categories based on days spent hunting: low frequency (1 to 2 days), medium frequency (3 to 4 days), and high frequency (> or =5 days). The influence of these variables to respondents' perceptions of overall quality was examined using a series of regression models. Variables found to be significant predictors of quality were wildlife interaction and harvest success. Hunters who killed a turkey reported a significantly higher quality season than those who did not kill a turkey. PMID:16132453

  11. Satellite services system overview

    NASA Technical Reports Server (NTRS)

    Rysavy, G.

    1982-01-01

    The benefits of a satellite services system and the basic needs of the Space Transportation System to have improved satellite service capability are identified. Specific required servicing equipment are discussed in terms of their technology development status and their operative functions. Concepts include maneuverable television systems, extravehicular maneuvering unit, orbiter exterior lighting, satellite holding and positioning aid, fluid transfer equipment, end effectors for the remote manipulator system, teleoperator maneuvering system, and hand and power tools.

  12. A report on syphilis control in Turkey

    PubMed Central

    Christiansen, Sven

    1954-01-01

    This report presents the results of a six-month survey of the nature and extent of venereal diseases in Turkey which was undertaken by the author, on behalf of WHO, at the request of the Turkish Government. The first part of the report outlines the present venereal-disease-control system and includes descriptions of the work undertaken by public authorities, hospitals and dispensaries, mobile venereal-disease-control teams, and laboratories; in the second part, the author enumerates certain recommendations for the intensification of the current control programme. These recommendations are particularly concerned with the control of syphilis (since the incidence of other venereal diseases in Turkey is of very secondary importance), and with the expansion, standardization, and co-ordination of serodiagnostic facilities and services. It is suggested that there might be a gradual intensification and reorientation of the present programme. A proposed plan of operations for an eight-year period is described. PMID:13182590

  13. Female breast cancer mortality rates in Turkey.

    PubMed

    Dogan, Nurhan; Toprak, Dilek

    2014-01-01

    The main objective of this study was to analyze the mortality trends of female breast cancer in Turkey between the years 1987-2008. The rates per 100,000 age-standardized to the European standard population were assessed and time trends presented using joinpoint regression analysis. Average annual percent change (AAPC), anual percent change (APC) and 95% confidence interval (CI) was calculated. Nearly 23,000 breast cancer deaths occurred in Turkey during the period 1987-2008, with the average annual age-standardized mortality rate (ASR) being 11.9 per 100,000 women. In the last five years, significant increases were observed in all age groups, but there was no significant change over the age of 65. In this period, the biggest significant increase was in the 45-54 age group (AAPC=4.3, 95%CI=2.6 to 6.0). PMID:25292030

  14. Satellite networks for education

    NASA Technical Reports Server (NTRS)

    Singh, J. P.; Morgan, R. P.; Rosenbaum, F. J.

    1972-01-01

    Satellite based educational networking is discussed with particular attention given to the potential uses of communications satellites to help meet educational needs in the United states. Four major subject areas were covered; (1) characteristics and structure of networks, (2) definition of pressures within educational establishment that provide motivation for various types of networks, (3) examination of current educational networking status for educational radio and television, instructional television fixed services, inter- and intra-state educational communication networks, computer networks, and cable television for education, and (4) identification of possible satellite based educational telecommunication services and three alternatives for implementing educational satellite systems.

  15. Satellite communication antenna technology

    NASA Technical Reports Server (NTRS)

    Mittra, R. (Editor); Imbriale, W. A. (Editor); Maanders, E. J. (Editor)

    1983-01-01

    A general overview of current technology in the field of communication satellite antennas is presented. Among the topics discussed are: the design of multiple beam systems; frequency reuse; and polarization control of antenna measurements. Consideration is also given to: contour beam synthesis; dual shaped reflector synthesis; beam shaping; and offset reflector design. The applications of the above technologies to present and future generations of communications satellites is considered, with emphasis given to such systems as: the Intelsats; the Defense Satellite Communications System, (DSCS-III); Satellite Business System (SBS), and Comstar.

  16. Satellite Antenna Systems

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Through the Technology Affiliates Program at the Jet Propulsion Laboratory, the ACTS antenna system was transferred from experimental testing status to commercial development with KVH Industries, Inc. The ACTS design enables mobile satellite antennas to remain pointed at the satellite, regardless of the motion or vibration on which it is mounted. KVH's first product based on the ACTS design is a land-mobile satellite antenna system that will enable direct broadcast satellite television aboard moving trucks, recreational vehicles, trains, and buses. Future products could include use in broadcasting, emergency medical and military vehicles.

  17. Methods of satellite oceanography

    NASA Technical Reports Server (NTRS)

    Stewart, R. H.

    1985-01-01

    The theoretical basis for remote sensing measurements of climate and ocean dynamics is examined. Consideration is given to: the absorption of electromagnetic radiation in the atmosphere; scattering in the atmosphere; and satellite observations using visible light. Consideration is also given to: the theory of radio scatter from the sea; scatter of centimeter waves from the sea; and the theory of operation of synthetic aperture radars. Additional topics include: the coordinate systems of satellite orbits for oceanographic remote sensing applications; the operating features of the major U.S. satellite systems for viewing the ocean; and satellite altimetry.

  18. Satellite Tracking System

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Researchers at the Center for Aerospace Sciences of the University of North Dakota (UND), Grand Forks, used three NASA Computer programs (SANDTRACKS, ODG, NORAD) to develop a Satellite Tracking System for real time utilization of TIROS weather/environment satellite information. SANDTRACKS computes the satellite's position relative to the Earth. ODG allows plotting a view of Earth as seen by the satellite. NORAD computes sight direction, visibility times and maximum elevation angle during each orbit. With the system, UND's Earth System Science Institute will be able to routinely monitor agricultural and environmental conditions of the Northern Plains.

  19. The WHO global alliance against chronic respiratory diseases in Turkey (GARD Turkey).

    PubMed

    Yorgancioğlu, A; Türktaş, H; Kalayci, O; Yardim, N; Buzgan, T; Kocabaş, A; Karlikaya, C; Yildiz, F; Ergün, P; Mungan, D; Kart, L; Göktaş, E; Musaonbaşioğlu, S; Gündoğan, A; Akdağ, R; Akçay, S; Akin, M; Akkurt, I; Altan, P; Altunsu, T; Arpaci, N; Aydin, C; Aydin, S; Aydinli, F; Aytaç, B; Bavbek, S; Biber, C; Bingöl Karakoç, G; Ceyhun, G; Cakir, B; Celik, G; Cetinkaya, T; Ciçek, M E; Coban, S C; Cobanoğlu, N; Com, S; Cöplü, L; Demirkazik, A; Doğan, E; Ekmekçi, E B; Elbir, M; Erdoğan, A; Ergüder, T; Gemicioğlu, B; Gögen, S; Gülbahar, O; Güngör, H; Horzum, E; Içer, Y; Imamecioğlu, A R; Kahraman, N; Kakillioğlu, T; Kalyoncu, F; Karakaya, M; Karakaya, G; Karaodul, G; Kesici, C; Keskinkiliç, B; Kilinç, O; Kirmizitaş, F; Kosdak, M; Köktürk, N; Metintaş, M; Numanoğlu, S C; Gümrükçüoğlu, O F; Onal, Z; Onal, B; Ozacar, R; Ozen, H A; Ozkan, S; Oztürk, F; Polat, H; Saçkesen, C; Selçuk, T; Serin, G; Sönmez, G; Sahin, M; Sahinöz, S; Sahinöz, T; Simşek, B; Tartan, N; Toprak, A; Tugay, T; Tuncer, A; Uçan, E S; Unüvar, N; Yapicikardeşler, B; Yildirim, N; Yol, S; Yüksel, H; Khaltaev, N; Cruz, A; Minelli, E; Bateman, E; Baena Cagnani, C; Dahl, R; Bousquet, J

    2009-01-01

    In order to prevent and control non-communicable diseases (NCDs), the 61st World Health Assembly has endorsed an NCD action plan (WHA resolution 61.14). A package for essential NCDs including chronic respiratory diseases (CRDs) has also been developed. The Global Alliance against Chronic Respiratory Diseases (GARD) is a new but rapidly developing voluntary alliance that is assisting World Health Organization (WHO) in the task of addressing NCDs at country level. The GARD approach was initiated in 2006. GARD Turkey is the first comprehensive programme developed by a government with all stakeholders of the country. This paper provides a summary of indicators of the prevalence and severity of chronic respiratory diseases in Turkey and the formation of GARD Turkey. PMID:20037863

  20. Healthcare Information Technology Infrastructures in Turkey

    PubMed Central

    Yuksel, M.; Ertürkmen, G. L.; Kabak, Y.; Namli, T.; Yıldız, M. H.; Ay, Y.; Ceyhan, B.; Hülür, Ü.; Öztürk, H.; Atbakan, E.

    2014-01-01

    Summary Objectives The objective of this paper is to describe some of the major healthcare information technology (IT) infrastructures in Turkey, namely, Sağlık-Net (Turkish for “Health-Net”), the Centralized Hospital Appointment System, the Basic Health Statistics Module, the Core Resources Management System, and the e-prescription system of the Social Security Institution. International collaboration projects that are integrated with Sağlık-Net are also briefly summarized. Methods The authors provide a survey of the some of the major healthcare IT infrastructures in Turkey. Results Sağlık-Net has two main components: the National Health Information System (NHIS) and the Family Medicine Information System (FMIS). The NHIS is a nation-wide infrastructure for sharing patients’ Electronic Health Records (EHRs). So far, EHRs of 78.9 million people have been created in the NHIS. Similarly, family medicine is operational in the whole country via FMIS. Centralized Hospital Appointment System enables the citizens to easily make appointments in healthcare providers. Basic Health Statistics Module is used for collecting information about the health status, risks and indicators across the country. Core Resources Management System speeds up the flow of information between the headquarters and Provincial Health Directorates. The e-prescription system is linked with Sağlık-Net and seamlessly integrated with the healthcare provider information systems. Finally, Turkey is involved in several international projects for experience sharing and disseminating national developments. Conclusion With the introduction of the “Health Transformation Program” in 2003, a number of successful healthcare IT infrastructures have been developed in Turkey. Currently, work is going on to enhance and further improve their functionality. PMID:24853036

  1. Hypertension and chronic kidney disease in Turkey.

    PubMed

    Sengul, Sule; Erdem, Yunus; Batuman, Vecihi; Erturk, Sehsuvar

    2013-12-01

    Worldwide, both hypertension and chronic kidney disease are major public health problems, due to their epidemic proportions and their association with high cardiovascular mortality. In 2003, the first Prevalence, awareness, treatment, and control of hypertension in Turkey (the PatenT) study was conducted in a nationally representative population (n=4910) by the Turkish Society of Hypertension and Renal Diseases, and showed that overall age- and sex-adjusted prevalence of hypertension in Turkey was 31.8%. The PatenT study also reported that overall awareness (40.7%), treatment (31.1%), and control rates (8.1%) of hypertension were strikingly low. Only 20.7% of the patients who were aware of their hypertension and receiving treatment had their blood pressure controlled to <140/90 mm Hg. In the Chronic Renal Disease in Turkey (CREDIT) study (n=10,748), the overall prevalence of chronic kidney (including all stages) disease was 15.7% and increased with advancing age. In the same population, the prevalence of hypertension, diabetes mellitus, dyslipidemia, obesity, and metabolic syndrome were reported as 32.7%, 12.7%, 76.3%, 20.1%, and 31.3%, respectively. The prevalence and awareness of hypertension in CREDIT population was 32.7% and 48.6%, respectively. According to the data obtained from national surveys, the prevalence of hypertension and chronic kidney disease in Turkey is alarmingly high. To improve prevention, early diagnosis, and treatment of these major public health problems, appropriate health strategies should be implemented by the government, together with medical societies, non-governmental organizations, industry, health-care providers, and academia. PMID:25019009

  2. Habitat Suitability Index Models: Eastern Wild Turkey

    USGS Publications Warehouse

    Schroeder, Richard L.

    1985-01-01

    A review and synthesis of existing information were used to develop a Habitat Suitability Index (HSI) model for the eastern wild turkey (Meleagris gallopavo sylvestris). The model consolidates habitat use information into a framework appropriate for field application, and is scaled to produce an index between 0.0 (unsuitable habitat) to 1.0 (optimum habitat). HSI models are designed to be used with Habitat Evaluation Procedures previously developed by the U.S. Fish and Wildlife Service.

  3. Channel stability of Turkey Creek, Nebraska

    USGS Publications Warehouse

    Rus, David L.; Soenksen, Philip J.

    1998-01-01

    Channelization on Turkey Creek and its receiving stream, the South Fork Big Nemaha River, has disturbed the equilibrium of Turkey Creek and has led to channel-stability problems, such as degradation and channel widening, which pose a threat to bridges and land adjacent to the stream. As part of a multiagency study, the U.S. Geological Survey assessed channel stability at two bridge sites on upper and middle portions of Turkey Creek by analyzing streambed-elevation data for gradation changes, comparing recent cross-section surveys and historic accounts, identifying bank-failure blocks, and analyzing tree-ring samples. These results were compared to gradation data and trend results for a U.S. Geological Survey streamflow-gaging station near the mouth of Turkey Creek from a previous study. Examination of data on streambed elevations reveals that degradation has occurred. The streambed elevation declined 0.5 m at the upper site from 1967-97. The streambed elevation declined by 3.2 m at the middle site from 1948-97 and exposed 2 m of the pilings of the Nebraska Highway 8 bridge. Channel widening could not be verified at the two sites from 1967-97, but a historic account indicates widening at the middle site to be two to three times that of the 1949 channel width. Small bank failures were evident at the upper site and a 4-m-wide bank failure occurred at the middle site in 1987 according to tree ring analyses. Examination of streambed-elevation data from a previous study at the lower site reveals a statistically significant aggrading trend from 1958-93. Further examination of these data suggests minor degradation occurred until 1975, followed by aggradation.

  4. An epornitic of Mycoplasma gallisepticum in turkeys.

    PubMed

    Mason, S J; Maiers, J D

    1984-01-01

    A major epornitic of Mycoplasma gallisepticum occurred in the Monroe, North Carolina, area between January and June of 1983. The outbreak involved 304,000 turkeys of various ages, which were slaughtered in the eradication program at a cost of more than $550,000 to growers and poultry companies. An infected peafowl was the likely source of infection on the first farm. Traffic between farms by growers and company personnel was theorized to be the means of further spread. PMID:6487195

  5. Hierarchical structure of Turkey's foreign trade

    NASA Astrophysics Data System (ADS)

    Kantar, Ersin; Deviren, Bayram; Keskin, Mustafa

    2011-10-01

    We examine the hierarchical structures of Turkey's foreign trade by using real prices of their commodity export and import move together over time. We obtain the topological properties among the countries based on Turkey's foreign trade during the 1996-2010 period by using the concept of hierarchical structure methods (minimal spanning tree, (MST) and hierarchical tree, (HT)). These periods are divided into two subperiods, such as 1996-2002 and 2003-2010, in order to test various time-window and observe the temporal evolution. We perform the bootstrap techniques to investigate a value of the statistical reliability to the links of the MSTs and HTs. We also use a clustering linkage procedure in order to observe the cluster structure much better. From the structural topologies of these trees, we identify different clusters of countries according to their geographical location and economic ties. Our results show that the DE (Germany), UK (United Kingdom), FR (France), IT (Italy) and RU (Russia) are more important within the network, due to a tighter connection with other countries. We have also found that these countries play a significant role for Turkey's foreign trade and have important implications for the design of portfolio and investment strategies.

  6. Assessing Poverty and Related Factors in Turkey

    PubMed Central

    Saatci, Esra; Akpinar, Ersin

    2007-01-01

    Poverty, a complex, multidimensional, and universal problem, has been conceptualized as income and material deprivation. In this article, we discuss poverty and related factors in Turkey. The absolute poverty line for Turkey was US $4 per capita per day. Turkey was ranked 92nd out of 177 countries with moderate human development in the 2006 Human Development Report. The individual food poverty rate was 1.35% and the non-food poverty rate was 25.6%. The highest poverty rate was among primary school graduates (42.5%; 38.5% for women and 46.8% for men). The rate for this group was higher in urban than in rural areas. Among poor people, 57.2% were married. The highest poverty rate was among agricultural workers (46.6%) and in Eastern and Southeastern Anatolia. Factors related to poverty were crowded households, unemployment, immigration, working for a daily wage in the agricultural and construction sector, low educational status, female sex or married status, lacking social insurance, and living in rural areas or in Eastern and Southeastern Anatolia. PMID:17948949

  7. Earthquake Hazard and Risk Assessment for Turkey

    NASA Astrophysics Data System (ADS)

    Betul Demircioglu, Mine; Sesetyan, Karin; Erdik, Mustafa

    2010-05-01

    Using a GIS-environment to present the results, seismic risk analysis is considered as a helpful tool to support the decision making for planning and prioritizing seismic retrofit intervention programs at large scale. The main ingredients of seismic risk analysis consist of seismic hazard, regional inventory of buildings and vulnerability analysis. In this study, the assessment of the national earthquake hazard based on the NGA ground motion prediction models and the comparisons of the results with the previous models have been considered, respectively. An evaluation of seismic risk based on the probabilistic intensity ground motion prediction for Turkey has been investigated. According to the Macroseismic approach of Giovinazzi and Lagomarsino (2005), two alternative vulnerability models have been used to estimate building damage. The vulnerability and ductility indices for Turkey have been taken from the study of Giovinazzi (2005). These two vulnerability models have been compared with the observed earthquake damage database. A good agreement between curves has been clearly observed. In additional to the building damage, casualty estimations based on three different methods for each return period and for each vulnerability model have been presented to evaluate the earthquake loss. Using three different models of building replacement costs, the average annual loss (AAL) and probable maximum loss ratio (PMLR) due to regional earthquake hazard have been provided to form a basis for the improvement of the parametric insurance model and the determination of premium rates for the compulsory earthquake insurance in Turkey.

  8. Local magnitude scale for earthquakes in Turkey

    NASA Astrophysics Data System (ADS)

    Kılıç, T.; Ottemöller, L.; Havskov, J.; Yanık, K.; Kılıçarslan, Ö.; Alver, F.; Özyazıcıoğlu, M.

    2016-06-01

    Based on the earthquake event data accumulated by the Turkish National Seismic Network between 2007 and 2013, the local magnitude (Richter, Ml) scale is calibrated for Turkey and the close neighborhood. A total of 137 earthquakes (Mw > 3.5) are used for the Ml inversion for the whole country. Three Ml scales, whole country, East, and West Turkey, are developed, and the scales also include the station correction terms. Since the scales for the two parts of the country are very similar, it is concluded that a single Ml scale is suitable for the whole country. Available data indicate the new scale to suffer from saturation beyond magnitude 6.5. For this data set, the horizontal amplitudes are on average larger than vertical amplitudes by a factor of 1.8. The recommendation made is to measure Ml amplitudes on the vertical channels and then add the logarithm scale factor to have a measure of maximum amplitude on the horizontal. The new Ml is compared to Mw from EMSC, and there is almost a 1:1 relationship, indicating that the new scale gives reliable magnitudes for Turkey.

  9. General aspect of pneumoconiosis in Turkey.

    PubMed

    Cimrin, Arif; Erdut, Zeki

    2007-05-01

    During the past 20 years number of definitive occupational diseases has not increased above 1500 case/year according to official statistics in Turkey. Although pneumoconiosis is the most diagnosed occupational disease, incidence of pneumoconiosis is very low.The present paper aims at reaching conclusions on the true dimension of the pneumoconiosis problem by evaluating whole the studies and case presentations related to coal mine dust and crystalline silica exposure within occupational environment.Regarding the results of the workplace-based studies it could be predicted that 20,000 out of 220,000 workers in mining sector could have pneumoconiosis and approximately 5,000 new pneumoconiosis cases might have occurred each year. Case presentations show high-level dust exposures present at the work places. These working conditions might cause acute pneumoconiosis. Poor working conditions exist especially at small and micro scale establishments.In Turkey, infrastructural and superstructural problems on workplace supervision and follow-up, legal processes on workers' health are complicated. Turkey has to provide healthy working conditions to those small-scale workplaces. Providing relevant assistance with activating people of the developed countries should be on top of the global efforts. PMID:21938215

  10. Assessing poverty and related factors in Turkey.

    PubMed

    Saatci, Esra; Akpinar, Ersin

    2007-10-01

    Poverty, a complex, multidimensional, and universal problem, has been conceptualized as income and material deprivation. In this article, we discuss poverty and related factors in Turkey. The absolute poverty line for Turkey was US$ 4 per capita per day. Turkey was ranked 92nd out of 177 countries with moderate human development in the 2006 Human Development Report. The individual food poverty rate was 1.35% and the non-food poverty rate was 25.6%. The highest poverty rate was among primary school graduates (42.5%; 38.5% for women and 46.8% for men). The rate for this group was higher in urban than in rural areas. Among poor people, 57.2% were married. The highest poverty rate was among agricultural workers (46.6%) and in Eastern and Southeastern Anatolia. Factors related to poverty were crowded households, unemployment, immigration, working for a daily wage in the agricultural and construction sector, low educational status, female sex or married status, lacking social insurance, and living in rural areas or in Eastern and Southeastern Anatolia. PMID:17948949

  11. A Full Pharmacological Analysis of the Three Turkey β-Adrenoceptors and Comparison with the Human β-Adrenoceptors

    PubMed Central

    Baker, Jillian G.

    2010-01-01

    Background There are three turkey β-adrenoceptors: the original turkey β-adrenoceptor from erythrocytes (tβtrunc, for which the X-ray crystal structure has recently been determined), tβ3C and tβ4C-receptors. This study examined the similarities and differences between these avian receptors and mammalian receptors with regards to binding characteristics and functional high and low affinity agonist conformations. Methodology/Principal Findings Stable cell lines were constructed with each of the turkey β-adrenoceptors and 3H-CGP12177 whole cell binding, CRE-SPAP production and 3H-cAMP accumulation assays performed. It was confirmed that the three turkey β-adrenoceptors are distinct from each other in terms of amino acid sequence and binding characteristics. The greatest similarity of any of the turkey β-adrenoceptors to human β-adrenoceptors is between the turkey β3C-receptor and the human β2-adrenoceptor. There are pharmacologically distinct differences between the binding of ligands for the tβtrunc and tβ4C and the human β-adrenoceptors (e.g. with CGP20712A and ICI118551). The tβtrunc and tβ4C-adrenoceptors appear to exist in at least two different agonist conformations in a similar manner to that seen at both the human and rat β1-adrenoceptor and human β3-adrenoceptors. The tβ3C-receptor, similar to the human β2-adrenoceptor, does not, at least so far, appear to exist in more than one agonist conformation. Conclusions/Significance There are several similarities, but also several important differences, between the recently crystallised turkey β-adrenoceptor and the human β-adrenoceptors. These findings are important for those the field of drug discovery using the recently structural information from crystallised receptors to aid drug design. Furthermore, comparison of the amino-acid sequence for the turkey and human adrenoceptors may therefore shed more light on the residues involved in the existence of the secondary

  12. Research on embryos in Turkey with ethical and legal aspects

    PubMed Central

    Vatanoğlu-Lutz, Emine Elif

    2012-01-01

    Technically, the term embryo refers to the products of conception after implantation into the wall of the womb, usually nearly two weeks after fertilization, up until the eighth week. Embryos contain stem cells which, according to scientists, could be used to cure a wide range of conditions. Stem cells can be coaxed into growing cells of any other type, which makes them potentially very useful indeed. However, removing stem cells from an embryo will kill the embryo, which some people object to. From the mid 1970s, IVF was being developed and research was carried out on the spare embryos produced. This research helped to improve IVF techniques, as well as to better understand the earliest stages of human development. Research also shed light on a variety of inheritable disorders. In Turkish Law, assisted reproduction treatment (ART) services are regulated with the Regulation of Assisted Reproductive Treatment Centers Act (RAPTCA) The Regulation was issued in 1987, but it has been amended several times since. Also, article 90 of the Turkish Penal Code covers some aspects of research on embryos. At the same time, the Biomedicine Convention (Oviedo Convention), signed by Turkey and which entered into force in 2003, has binding regulations about this issue. Different legal regulations and some ethical guidelines are in conflict with each other, creating much confusion for the researchers. In this paper these conflicts are discussed, giving some practical proposals. PMID:24592037

  13. Processing of satellite imagery at the National Environmental Satellite Service

    NASA Technical Reports Server (NTRS)

    Crowe, M.

    1977-01-01

    The National Environmental Satellite Service (NESS) image product processing system is described. Other topics discussed include: (1) image processing of polar-orbiter satellite data; (2) image processing of geostationary satellite data; and (3) quality assurance and product monitoring.

  14. National Seismic Network System of Turkey

    NASA Astrophysics Data System (ADS)

    Zunbul, S.; Kadirioğlu, F. T.; Holoğlu, N.; Kartal, R. F.; Kiliç, T.; Yatman, A.; Iravul, Y.; Tüzel, B.

    2009-04-01

    In order to mitigate disaster losses, it is necessary to establish an effective disaster management and risk system. The first step of the management is constituted by preparedness studies before the earthquake (disaster). In order to determinate disaster and risk information it is necessary to have a seismological observation network. Due to the monitoring of the earhquakes in the country-wide scale, recording, evaluation, archieving and to inform to the public autority, the project named "Development of the National Seismic Network Project-USAG" has been started. 6 Three Component Short Period, 63 Broad-band, 13 One Component Short Period stations, 65 Local Network- Broad-band, and 247 accelerometers have been operated in the frame of this project. All of the stations transmit continuously their signal to the ERD (Earthquake Research Department) seismic data center in Ankara. Capability of the network is to determine an earthquake which is minimum local magnitude ML= 2.8 generally, in some region local magnitude threshold is ML=1.5 (the places where the stations are concentrated). Earthquake activity in Turkey and surrounding region has been observed 7 days / 24 hours, in ERD data center in Ankara. After the manuel location of an earthquake, If the magnitude is over 4.0, system sends to SMS message automaticaly to the authorized people and immediately press, public and national-local crisis center, scientific institutions are informed by fax and e-mail. Data exchange has been carried out to EMSC-CSEM. During the İnstallation of the broad-band stations, the seismotectonics of the region has been taken into consideration. Earthqauke record stations are concentrated at the most important fault zones in Turkey; North Anatolian Fault System, East Anatolian Fault System, Bitlis Overlap Belt and Aegean Graben (or opening) System. After 1999 İzmit and Düzce earthquakes, the number of the seismic stations in Turkey have been increased each passing year. In this study

  15. Communication satellite technology trends

    NASA Technical Reports Server (NTRS)

    Cuccia, Louis

    1986-01-01

    A chronology of space-Earth interconnectivity is presented. The Advanced Communications Technology Satellite (ACTS) system, Land Mobile Satellite, space-Earth antennas, impact of antenna size on coverage, intersatellite links are outlined. This presentation is represented by graphs and charts only.

  16. Communications technology satellite

    NASA Technical Reports Server (NTRS)

    1976-01-01

    A description of the Communications Technology Satellite (CTS), its planned orbit, its experiments, and associated ground facilities was given. The communication experiments, to be carried out by a variety of groups in both the United States and Canada, include tele-education, tele-medicine, community interaction, data communications and broadcasting. A historical summary of communications satellite development was also included.

  17. Amateur Radio Satellite Communications.

    ERIC Educational Resources Information Center

    Koch, David P.

    The Amateur Radio Satellite Communications project had, as its goal, the assembly of an amateur radio satellite station in a high school physics classroom. Specific objectives were to provide: (1) a special source of interest as a motivator for attracting students and building public relations; (2) a center of interest as a motivator for the study…

  18. Satellite Teleconference Final Report.

    ERIC Educational Resources Information Center

    Elgin Community Coll., IL.

    The vocational education satellite teleconference project accomplished two goals: (1) identified, acquired, copied, and distributed to the Illinois Vocational Curriculum Center 100 marketing or training videotapes for staff development and classroom use; and (2) provided from 15-25 variable time (1- to 3-hour) satellite teleconferences in four…

  19. Audio direct broadcast satellites

    NASA Technical Reports Server (NTRS)

    Miller, J. E.

    1983-01-01

    Satellite sound broadcasting is, as the name implies, the use of satellite techniques and technology to broadcast directly from space to low-cost, consumer-quality receivers the types of sound programs commonly received in the AM and FM broadcast bands. It would be a ubiquitous service available to the general public in the home, in the car, and out in the open.

  20. Advanced communications satellites

    NASA Technical Reports Server (NTRS)

    Sivo, J. N.

    1980-01-01

    The increase in demand for satellite communications services brought about shortages in available transponder capacity, especially at C-band. Interest shifted to the Ku-band frequency and currently carriers are rapidly moving to secure orbital slots for future satellite development. Projections of communications service demands over the next decade indiate growth in voice, data, and video services such that saturation of both C-band and Ku-band will occur by 1990. Emphasis must and will shift to Ka-band (20/30 GHz) frequency for fixed-satellite service. Advanced technologies such as multibeam antennas coupled with on-board satellite switching to allow implementation in this band of very high capacity satellite systems will be applied to meet the demand. Satellite system concepts that are likely in the 1990's and are likely to bring a new dimension to satellite delivered communication service are presented. The NASA 30/20 GHz communications satellite system demonstration program is discussed with emphasis on the related technology development.

  1. Laser Geodynamics Satellite I

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The LAGEOS I (Laser Geodynamics Satellite) was developed and launched by the Marshall Space Flight Center on May 4, 1976 from Vandenberg Air Force Base, California . The two-foot diameter satellite orbited the Earth from pole to pole and measured the movements of the Earth's surface.

  2. Telecommunications satellite systems

    NASA Astrophysics Data System (ADS)

    Ramat, Pierre

    1992-12-01

    A survey of the telecommunications satellite field is presented. After a review of the historical and regulatory background, the main technical features of satellite networks are analyzed, and existing international and national systems are considered. Particular attention is given to Intelsat, Inmarsat, Eutelsat, and Telecom 1 and 2. Future technical and economic trends are then projected.

  3. Satellites in Schools.

    ERIC Educational Resources Information Center

    Underwood, C. I.; And Others

    1987-01-01

    Discusses the use of satellite data in physics classrooms. Describes the apparatus that can be used to collect and analyze data. Provides examples of how telemetry data transmitted by the satellite UoSAT-2 can be used not only in teaching physics, but also in geography, mathematics, and information technology. (TW)

  4. Outer planets satellites

    NASA Technical Reports Server (NTRS)

    Morrison, D.

    1983-01-01

    The present investigation takes into account the published literature on outer planet satellites for 1979-1982. It is pointed out that all but three (the moon and the two Martian satellites) of the known planetary satellites are found in the outer solar system. Most of these are associated with the three regular satellite systems of Jupiter, Saturn, and Uranus. The largest satellites are Titan in the Saturn system and Ganymede and Callisto in the Jupiter system. Intermediate in size between Mercury and Mars, each has a diameter of about 5000 km. Presumably each has an internal composition about 60 percent rock and 40 ice, and each is differentiated with a dense core extending out about 75 percent of the distance to the surface, with a mantle of high-pressure ice and a crust of ordinary ice perhaps 100 km thick. Attention is also given to Io, Europa, the icy satellites of Saturn, the satellites of Uranus, the small satellites of Jupiter and Saturn, Triton and the Pluto system, and plans for future studies.

  5. Signals from Communications Satellites.

    ERIC Educational Resources Information Center

    Thomsen, Volker

    1996-01-01

    Discusses the Doppler effect for relative motion between a source of waves and an observer and the orbital dynamics of communications satellites. Presents preliminary calculations of the satellite's altitude and linear velocity using only the concepts of the Doppler shift and the mechanics of motion in a circular path. (JRH)

  6. Engineers checkout Early Bird-Communication Satellite

    NASA Technical Reports Server (NTRS)

    1984-01-01

    Engineers Stanley R. Peterson (left) and Ray Bowerman (right), checkout the Early Bird, the world's first communication satellite. NASA launched the satellite built by Hughes Aircraft Corporation on April 6, 1955 at 6:48pm E.S.T. from Complex 17a at Cape Kennedy, Florida. Early Bird was built for the Communications Satellite Corporation and weighed about 85 pounds after being placed in a synchronous orbit of 22,300 miles above the earth. It was positioned over the Atlantic to provide 240 two-way telephone channels or 2-way television between Europe and North America. The outer surface of Early Bird was covered with 6,000 silicon-coated solar cells, which absorbed the sun's rays to provide power to the satellite for its intricate transmitting and receiving equipment.

  7. Communications satellites - Countdown for INTELSAT VI

    NASA Astrophysics Data System (ADS)

    Pollack, L.; Weiss, H.

    1984-02-01

    Microwave technology development over the last 20 years has expanded the transmission bandwidth/satellite in earth-synchronous orbit from 50 to more than 3000 MHz. Solar cell, electrical battery, stationkeeping and microwave amplification technology advancements have increased satellite service lives from 1.5 years to 10. The INTELSAT geostationary communications satellites which are scheduled for introduction into the global system in 1986 will have the capacity for 40,000 telephone channels, as well as two TV programs. The satellite generation beyond that of 1986, which is currently in the design stage for expanded capacity, will be needed by the mid-1990s to meet traffic demand and is projected to incorporate such features as 20- and 30-GHz communications, onboard signal processing and switching, and more bandwidth-efficient modulation.

  8. The Satellite Situation Center

    NASA Technical Reports Server (NTRS)

    Teague, M. J.; Sawyer, D. M.; Vette, J. I.

    1982-01-01

    Considerations related to the early planning for the International Magnetospheric Study (IMS) took into account the desirability of an establishment of specific entities for generating and disseminating coordination information for both retrospective and predictive periods. The organizations established include the IMS/Satellite Situation Center (IMS/SSC) operated by NASA. The activities of the SSC are related to the preparation of reports on predicted and actually achieved satellite positions, the response to inquiries, the compilation of information on satellite experiments, and the issue of periodic status summaries. Attention is given to high-altitude satellite services, other correlative satellite services, non-IMS activities of the SSC, a summary of the SSC request activity, and post-IMS and future activities.

  9. Satellite networks for education.

    NASA Technical Reports Server (NTRS)

    Singh, J. P.; Morgan, R. P.; Rosenbaum, F. J.

    1972-01-01

    Consideration of satellite-based educational networking. The characteristics and structure of networks are reviewed, and pressures within the educational establishment that are providing motivation for various types of networks are discussed. A number of studies are cited in which networking needs for educational sectors and services are defined. The current status of educational networking for educational radio and television, instructional television fixed services, inter- and intrastate educational communication networks, computer networks, cable television for education, and continuing and proposed educational experiments using NASA's Applications Technology Satellites is reviewed. Possible satellite-based educational telecommunication services and three alternatives for implementing educational satellite systems are described. Some remarks are made concerning public policy aspects of future educational satellite system development.

  10. Influence of season and sex on hemato-biochemical traits in adult turkeys under arid tropical environment

    PubMed Central

    Gattani, Anil; Pathak, Arti; Kumar, Ajeet; Mishra, Vaibhav; Bhatia, Jitendra Singh

    2016-01-01

    Aim: The objective of this study was to evaluate the effect of season and sex on hemato-biochemical parameters of turkey (Meleagris gallopavo) in the arid tropical environment. Materials and Methods: The experiment was conducted on 20-week old turkeys consisting of 20 males and 20 females. Blood was collected from all turkeys during January and May. Hemoglobin (Hb), red blood cell (RBC), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were estimated in whole blood and glucose, protein, albumin, globulin, A/G ratio, calcium, phosphorus, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) in serum. Result: Season has significant (p<0.05) effect on Hb concentration, RBC, and PCV in both male and female. Male has significantly higher (p<0.05) Hb concentration, RBC, and PCV. There is no significant effect of sex, and season was observed on MCV, MCH, and MCHC. Glucose, protein, albumin, globulin, and A/G ratio were significantly (p<0.05) affected by season and sex. AST and ALT were significantly (p<0.05) affected by season in both sexes. There is no significant difference was recorded on calcium, phosphorus due to season and sex. Conclusion: Under arid tropical environment, turkey hemato-biochemical parameters are influenced by both sex and season. PMID:27284232

  11. Role of G protein-coupled estrogen receptor-1, matrix metalloproteinases 2 and 9, and heparin binding epidermal growth factor-like growth factor in estradiol-17β-stimulated bovine satellite cell proliferation.

    PubMed

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

    2014-10-01

    In feedlot steers, estradiol-17β (E2) and combined E2 and trenbolone acetate (a testosterone analog) implants enhance rate and efficiency of muscle growth; and, consequently, these compounds are widely used as growth promoters. Although the positive effects of E2 on rate and efficiency of bovine muscle growth are well established, the mechanisms involved in these effects are not well understood. Combined E2 and trenbolone acetate implants result in significantly increased muscle satellite cell number in feedlot steers. Additionally, E2 treatment stimulates proliferation of cultured bovine satellite cells (BSC). Studies in nonmuscle cells have shown that binding of E2 to G protein-coupled estrogen receptor (GPER)-1 results in activation of matrix metalloproteinases 2 and 9 (MMP2/9) resulting in proteolytic release of heparin binding epidermal growth factor-like growth factor (hbEGF) from the cell surface. Released hbEGF binds to and activates the epidermal growth factor receptor resulting in increased proliferation. To assess if GPER-1, MMP2/9, and/or hbEGF are involved in the mechanism of E2-stimulated BSC proliferation, we have examined the effects of G36 (a specific inhibitor of GPER-1), CRM197 (a specific inhibitor of hbEGF), and MMP-2/MMP-9 Inhibitor II (an inhibitor of MMP2/9 activity) on E2-stimulated BSC proliferation. Inhibition of GPER-1, MMP2/9, or hbEGF suppresses E2-stimulated BSC proliferation (P < 0.001) suggesting that all these are required in order for E2 to stimulate BSC proliferation. These results strongly suggest that E2 may stimulate BSC proliferation by binding to GPER-1 resulting in MMP2/9-catalyzed release of cell membrane-bound hbEGF and subsequent activation of epidermal growth factor receptor by binding of released hbEGF. PMID:25010024

  12. Climate change and glacier retreat from 1955 to 2006 on Cilo Mountains, Southeast Anatolia, Turkey

    NASA Astrophysics Data System (ADS)

    Yeşilyurt, Serdar; Uǧur, Doǧan; Kılar, Hatice

    2013-04-01

    Alpine glaciers are amongst key indicators of global-scale climate changes because of their natural dynamics and quick response to global warming. Although there is vast number of studies on recent glaciers of the world, less attention has been paid to the glaciers of Turkey and the Middle East. In the present study, present glaciers of Cilo Mountains (4135 m) located in Southeast Anatolia, one of the most important recent glacier areas of Turkey, is dealt with within the context of the impacts of climatic changes on glaciers. Based on aerial photographs taken in 1955, 1968 and 1988 together with Quickbird satellite images taken in 2006, four main stages were examined using remote sensing and GIS technologies. The paleo-glacier cover of the Last Glacial age (most likely the Last Glacial Maximum) on the Cilo Range was about 100 km² in area as compared to the actual glaciers found in the three valley system around Uludoruk summit with an area of only 5.6 km². Actual glacier have retreated between 100 and 360 m in the period from 1955 to 2006. According to elevation, thickness-mass characteristics of the glaciers and geomorphic conditions of their cirques, retreat rates were found to be between 2 and 7 m/yr. The ages of young terminal moraines were also calculated on the basis of annual decline rates of these glaciers. Consequently, the oldest moraines should have probably been deposited between 1850 and 1870 matching end of the Little Ice Age. This age is compatible with the glacier retreat of the European Alps. We determined a warming trend both in summer temperatures and annual averages based on data from three meteorological stations located in the vicinity of this mountain area. Keywords: Cilo Mountains, actual glacier, glacier retreat, climate change, Little Ace Age, Turkey

  13. Quality of Life in Ageing Societies: Italy, Portugal, and Turkey

    ERIC Educational Resources Information Center

    Arun, Ozgur; Cevik, Aylin Cakiroglu

    2011-01-01

    The aim of this study was to compare and analyze the quality of life of the elderly in three aging countries: Italy, Portugal, and Turkey. This was done by using data provided by the European Quality of Life Survey completed in 2004. By doing so, we could then operationalize the conditions of the elderly in Turkey who have a rapid aging process…

  14. Applications and Problems of Computer Assisted Education in Turkey

    ERIC Educational Resources Information Center

    Usun, Salih

    2006-01-01

    This paper focuses on the Computer Assisted Education (CAE) in Turkey; reviews of the related literature; examines the projects, applications and problems on the Computer Assisted Education (CAE) in Turkey compares with the World; exposes the positive and negative aspects of the projects; a number of the suggestion presents on the effective use of…

  15. Regulation of waste and waste management in Turkey.

    PubMed

    Gören, Sami; Ozdemir, Feyza

    2011-04-01

    Industrial and technological developments have increased rapidly throughout the world including Turkey. Furthermore, the population of Turkey is also increasing and the ever-increasing consumption creates larger amounts of waste materials and adversely affects the environment and human health. The development of a waste management and disposal system has become necessary in all countries of the world. As part of the process of seeking entry to the European Union, Turkey continues to prepare the necessary legislation to satisfy European Union regulations for the disposal of solid waste, packaging waste, biodegradable waste and medical waste materials within the framework of the strategy. An integrated waste management system is necessary for each town in Turkey that is suitable for the different contents and increasing amounts of waste produced. In the present study, Turkey's geographical regions were examined in terms of population and the total amount of solid waste generated in each province to produce detailed data for the Turkish Ministry of Environment and Forestry. As a result of this study, it is understood that Turkey has drawn up a 'road map' which will be followed by the 2008-2012 Waste Management Action Plan. To achieve this, the Ministry of the Environment and Forestry, Turkey and the municipalities must fulfill the tasks that have been allocated to them. Turkey will attain the European Union standards for waste management if these tasks lead to the achievement of the targets within the action plan. PMID:20686052

  16. Perspectives on medical school library services in Turkey.

    PubMed

    Brennen, P W; Blackwelder, M B; Kirkali, M

    1987-07-01

    This paper gives a brief overview of medical education in Turkey and shows the impact of established social, educational, and economic patterns upon current medical library services. Current statistical information is given on the twenty-two medical school libraries in Turkey. Principal problems and chief accomplishments with library services are highlighted and discussed. PMID:3676535

  17. Accreditation Policies of Turkey in Primary and Secondary Education

    ERIC Educational Resources Information Center

    Furuzan, Verda Gizem

    2012-01-01

    Turkey's quality of education is being improved in order to become a member of EU (European Union), and Turkey is following the EU's system of educational policies. In the field of education, to encourage teaching and learning, accreditation process is used. It helps programs improve and be accountable for their quality. Accreditation provides…

  18. Socioscientific Issues in Science Education: The Case of Turkey

    ERIC Educational Resources Information Center

    Topcu, Mustafa Sami; Mugaloglu, Ebru Zeynep; Guven, Devrim

    2014-01-01

    The purpose of this study is to identify the foci and results of studies on socioscientific issues (SSI) conducted in Turkey. Additionally, the study aimed to compare the results of this study with ones conducted internationally. For this aim, a literary review of empirical studies related to SSI conducted in Turkey was carried out. Four criteria…

  19. Stress-induced immunosupression and gangrenous dermatitis in turkeys

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our laboratory has been researching the etiology of turkey osteomyelitis complex (TOC) for the past 16 years and we have determined that this syndrome is caused by the inability of some fast-growing male turkeys to cope with production stressors. While immunosuppressive viruses have traditionally be...

  20. Perspectives on medical school library services in Turkey.

    PubMed Central

    Brennen, P W; Blackwelder, M B; Kirkali, M

    1987-01-01

    This paper gives a brief overview of medical education in Turkey and shows the impact of established social, educational, and economic patterns upon current medical library services. Current statistical information is given on the twenty-two medical school libraries in Turkey. Principal problems and chief accomplishments with library services are highlighted and discussed. PMID:3676535