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1

The effect of early dietary amino acid levels on muscle satellite cell dynamics in turkeys.  

PubMed

Understanding the relationship between nutrition and satellite cell activity will be beneficial in obtaining optimal muscle growth and meat production. The objective of this study was to evaluate the effect of early post-hatch levels of dietary amino acids+/-0.88 NRC, 1.00 NRC, and 1.12 NRC), and feed deprivation on the satellite cell mitotic activity, pectoralis thoracicus muscle weight, and body weight of male turkeys (Meleagris gallopavo). Birds from each treatment were injected with 5-bromo-2'-deoxyuridine (BrdU) to label mitotically active cells. The right pectoralis thoracicus was harvested 1 h after BrdU injection for immunohistochemical and myofiber diameter analysis. On the third day post-hatch, satellite cell mitotic activity was the highest (P<0.05) in the 0.88 NRC amino acid treatment group and the lowest (P<0.05) in the feed-deprived group. On the fourth day post-hatch, feed-deprived birds exhibited the lowest (P<0.05) satellite cell mitotic activity and muscle weight. At 140 days of age, there were no significant differences (P>0.05) between treatments in body weight or pectoralis thoracicus muscle weight. Research evaluating species-related differences in apoptotic events and in genes regulating cell proliferation may be necessary to devise feeding strategies aimed at obtaining optimal pectoralis thoracicus muscle yield at market age. PMID:17644018

Nierobisz, L S; Felts, V; Mozdziak, P E

2007-06-23

2

Growth and sex effects on the expression of syndecan-4 and glypican-1 in turkey myogenic satellite cell populations.  

PubMed

The adult skeletal muscle stem cells, satellite cells, are responsible for skeletal muscle growth and regeneration. Satellite cells represent a heterogeneous cell population that differentially express cell surface markers. The membrane-associated heparan sulfate proteoglycans, syndecan-4, and glypican-1, are differentially expressed by satellite cells during the proliferation and differentiation stages of satellite cells. However, how the population of syndecan-4- or glypican-1-positive satellite cells changes during proliferation and differentiation, and how sex and muscle growth potential affect the expression of these genes is unknown. Differences in the amount of satellite cells positive for syndecan-4 or glypican-1 would affect the process of proliferation and differentiation which would impact both muscle mass accretion and the regeneration of muscle. In the current study, the percentage of satellite cells positive for syndecan-4 or glypican-1 from male and female turkeys from a Randombred Control Line 2 and a line (F) selected for increased 16-week body weight were measured during proliferation and differentiation. Growth selection altered the population of syndecan-4- and glypican-1-positive satellite cells and there were sex differences in the percentage of syndecan-4- and glypican-1-positive satellite cells. This study provides new information on dynamic changes in syndecan-4- and glypican-1-positive satellite cells showing that they are differentially expressed during myogenesis and growth selection and sex affects their expression. PMID:23435996

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

2013-02-24

3

[Are satellite cells stem cells?].  

PubMed

Satellite cells, localized in the niche between the membrane of muscle fiber and basal lamina that surrounds it, serve as a source of myoblasts that are necessary for both growth and regeneration of skeletal muscle. Apart from their ability to convert into myoblasts, satellite cells are also able to self-renew, thus, they meet requirements for tissue specific, unipotent stem cells. Recently conducted research revealed that population of satellite cells is heterogeneous. The article summarizes current information on biology and characteristics of satellite cells, and also describes models concerning mechanisms of self-renewal and differentiation of satellite cells. Experiments regarding in vitro differentiation of satellite cells into other cell types are also discussed. Moreover, other population of stem cells localized in the muscle are described in this review. PMID:24044285

Archacka, Karolina; Kowalski, Kamil; Brzóska, Edyta

2013-01-01

4

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

Microsoft Academic Search

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

Orhan Gökdemir; Özgür Beser; Serdar Sürer

2010-01-01

5

Psychiatric problems within the satellite-extended families of Turkey.  

PubMed

The many Turkish villagers who now migrate to large Turkish cities or enter the European labor force try to create models of the extended families they leave behind. Their satellite families necessarily drift away from tradition, however, in the direction of greater independence. This process often triggers psychiatric symptom formation. PMID:984261

Ozbek, A; Volkan, V D

1976-10-01

6

Satellite based estimates of terrestrial water storage variations in Turkey  

NASA Astrophysics Data System (ADS)

In recent years, the Gravity Recovery and Climate Experiment (GRACE) has provided a new tool to study terrestrial water storage variations (TWS) at medium and large spatial scales, providing quantitative measures of TWS change. Linear trends in TWS variations in Turkey were estimated using GRACE observations for the period March 2003 to March 2009. GRACE showed a significant decrease in TWS in the southern part of the central Anatolian region up to a rate of 4 cm/year. The Global Land Data Assimilation System (GLDAS) model also captured this TWS decrease event but with underestimated trend values. The GLDAS model represents only a part of the total TWS variations, the sum of soil moisture (2 m column depth) and snow water equivalent, ignoring groundwater variations. Therefore, GLDAS model derived TWS variations were subtracted from GRACE derived TWS variations to estimate groundwater storage variations. Results revealed that decreasing trends of TWS observed by GRACE in the southern part of central Anatolia were largely explained by the decreasing trends of groundwater variations which were confirmed by the limited available well groundwater level data in the region.

Lenk, Onur

2013-07-01

7

Satellite Monitoring of Hazards: A Focus on Istanbul, Turkey  

NASA Astrophysics Data System (ADS)

Satellite remote sensing data can provide important information on ground displacement, which can help scientists better understand and monitor geohazards such as earthquakes, volcano unrest, or landslides. However, access to such data and their results often has been difficult or has occurred with significant delay. As a result, a remotely sensed assessment of ground displacements is often not available until months or years after the occurrence of a natural disaster. In an attempt to facilitate access to satellite radar data and associated results in near real time, and to allow integration with other space-based and ground-based observation resources, the geohazards scientific community together with the European Space Agency (ESA) initiated the Geohazard Supersites program. As a contribution to risk reduction, this program seeks to promote data use and advance scientific research before, during, and after natural disasters. This program is contributing to the Group on Earth Observations (GEO) theme “Reducing the loss of life and property from natural and human-induced disasters.” GEO is coordinating efforts to build a Global Earth Observation System of Systems, or GEOSS, launched by the leading industrialized countries in response to the 2002 World Summit on Sustainable Development.

Walter, T. R.; Manzo, M.; Manconi, A.; Solaro, G.; Lanari, R.; Motagh, M.; Woith, H.; Parolai, S.; Shirzaei, M.; Zschau, J.; Baris, S.; Ansal, A.

2010-09-01

8

THE SATELLITE CELL OF SKELETAL MUSCLE FIBRES  

Microsoft Academic Search

Satellite cells of adult skeletal muscle fibres are myogenic monoculeated cells that are closely attached to muscle fibres. These cells provide new myonuclei during growth and regeneration; myonuclei are postmitotic. Three to 11 of myonuclei seen by light microscopy in reality are satellite cell nuclei. Developing muscles contain up to 35% satellite cells. Their incidence decreases after denervation and possibly

Henning Schmalbruch

2006-01-01

9

Muscle satellite cell heterogeneity: in vitro and in vivo evidences for populations that fuse differently  

Microsoft Academic Search

During development, muscle growth results from the proliferation of satellite cells (SC) and their fusion with fibers. Several studies revealed heterogeneity of SC population notably based on the proliferation rate. Here, we examined the SC characteristics of turkey skeletal muscles in terms of proliferation and more specifically fusion, to define if the ability of these cells to fuse may represent

Karl Rouger; Mickael Brault; Nathalie Daval; Isabelle Leroux; Lydie Guigand; Julie Lesoeur; Bernard Fernandez; Yan Cherel

2004-01-01

10

Coseismic Horizontal Offsets and Fault-Trace Mapping Using Phase Correlation of IRS Satellite Images: The 1999 Izmit (Turkey) Earthquake  

Microsoft Academic Search

On August 17, 1999, a strong earthquake (Mw ?? 7.4) occurred along the western sector of the North Anatolian Fault system in Turkey. The epicenter was located near the city of Izmit, 50 km east of Istanbul. Previous works determined the coseismic surface displacements by satellite synthetic aperture radar (SAR) interferometry (InSAR) and satellite optical-image correlation. In 1999, the highest

Pablo J. Gonzalez; Marco Chini; Salvatore Stramondo; José Fernandez

2010-01-01

11

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

NASA Astrophysics Data System (ADS)

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.

Scardozzi, Giuseppe

2008-10-01

12

Satellite cell therapy - from mice to men  

PubMed Central

Satellite cells are rare mononuclear skeletal muscle-resident cells that are the chief contributors to regenerative myogenesis following muscle injury. Although first identified more than 50 years ago, it is only recently that the murine satellite cell has become molecularly defined with the ability to prospectively isolate these cells from their niche. Human satellite cells are considerably less well understood with relatively few studies having been performed on them. In this review, a critical evaluation of this literature is provided along with a discussion of the practical and methodological issues involved with research on human satellite cells. The therapeutic potential of these and other cells types is also discussed, and the various challenges that face satellite cell therapy are addressed.

2013-01-01

13

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

NASA Astrophysics Data System (ADS)

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 products have been produced for around 12 years from 2000 to 2012 and it is being produced daily as the data is available. 72% overall accuracy was obtained from the validation analysis. Our website will be available to give service to our users to make analysis on snow extent with a long time series database for free. By the help of WEBGIS interface it is going to be possible to produce time series of snow cover areas, and produce graphs and summary statistics for a better management of information on snow cover in various fields from flood forecast integration, energy production planning of hydropower plants which are fed from snow melting, and producing input for climate models.

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

2012-04-01

14

Isolation and characterization of canine satellite cells  

Microsoft Academic Search

Summary  Satellite cells were isolated from biopsies of the biceps femoris of adult dogs. Virtually all cells expressed muscle-specific\\u000a proteins. Proliferation of satellite cells increased as the concentration of fetal calf serum (FCS) was increased from 1 to\\u000a 10% of the basal medium. The addition of mitogenic growth factors resulted in greater proliferation than that of cells cultured\\u000a in basal medium

J. Michal; Z. Xiang; G. Davenport; M. Hayek; M. V. Dodson; K. M. Byrne

2002-01-01

15

Satellite cells, the engines of muscle repair  

Microsoft Academic Search

Satellite cells are a heterogeneous population of stem and progenitor cells that are required for the growth, maintenance and regeneration of skeletal muscle. The transcription factors paired-box 3 (PAX3) and PAX7 have essential and overlapping roles in myogenesis. PAX3 acts to specify embryonic muscle precursors, whereas PAX7 enforces the satellite cell myogenic programme while maintaining the undifferentiated state. Recent experiments

Yu Xin Wang; Michael A. Rudnicki

2011-01-01

16

Cell cycle commitment of rat muscle satellite cells  

Microsoft Academic Search

Satellite celts of adult muscle are quiescent myogenic stem cells that can be induced to enter the cell cycle by an extract of crushed muscle (Bischoff, R. 1986. Dev. Biol. 115:140-147). Here, evidence is presented that the extract acts transiently to commit cells to enter the cell cycle. Satellite cells associated with both live and killed rat myofibers in culture

Richard Bischoff

1990-01-01

17

Phospho-MAPK as a marker of myogenic satellite cell responsiveness to growth factors.  

PubMed

To determine if differential response to growth factor stimuli between subpopulations of satellite cells was due to variation in the levels of activated intracellular signaling proteins, the levels of phospho-MAPK (phospho-ERK 1/2) were determined in clonal populations of turkey (Meleagris gallopavo) satellite cells. Relative levels of phospho-ERK 1/2 between clones were determined by Western blotting of extracts from satellite cells exposed to growth factor stimuli. Initial measurements using serum mitogenic stimuli showed differences in phospho-MAPK levels between the clonal subpopulations, but the responses did not correlate with proliferation rates of the individual clones (P>0.05). IGF-I alone did not increase phospho-MAPK levels compared to unstimulated controls (P>0.05), whereas FGF-2 did increase levels (P<0.05). A synergistic response was seen in satellite cells as well as embryonic myoblasts administered both IGF-I and FGF-2. When administered FGF-2 and IGF-I, 2 of the slow growing satellite cell clones exhibited lowest levels of phospho-MAPK (P<0.05). One of the slow growing clones had levels of phospho-MAPK similar to the three fast growing clones (P>0.05). The results suggest that variation in responsiveness to growth factor stimuli among satellite cell populations within muscles may be due to several different reasons. Some differences in cell responsiveness appear to be due to variation in phospho-MAPK generation. PMID:18226572

McFarland, Douglas C; Pesall, Jane E

2007-12-04

18

Water quality monitoring using satellite image data: a case study around the Salt Lake in Turkey  

Microsoft Academic Search

Rapid urbanization and increasing agricultural activities raises risks of surface water impoundment pollution at the Salt Lake which is one of the most important natural sources in Turkey. The Lake is a hazardous region for surface measurements especially in spring months due to its bottom covered with a 1 to 30 cm. salt layer. It is, therefore, necessary to make

Cankut Örmeci; Semih Ekercin

2005-01-01

19

Analysis of urban growth using multi-temporal satellite data in Istanbul, Turkey  

Microsoft Academic Search

Uncontrolled population growth, especially in developing countries, causes serious problems, such as scarcity of food, informal settlements, environmental pollution, destruction of ecological structure, unemployment, etc. This phenomenon will require advanced methodologies, such as space technologies, to enable city planners, economists, environmentalists, ecologists and resource managers to solve these problems. In Turkey, as a result of the undesired population growth, new

D. Maktav; F. S. Erbek

2005-01-01

20

The Maras triple junction (southern Turkey) based on digital elevation model and satellite imagery interpretation  

Microsoft Academic Search

This paper describes major structures in the area of the triple junction of the African, Anatolian and Arabian plates near Maras (southern Turkey). A review of the literature on the paleogeographic evolution since mid-Cretaceous time leads to the idea of the southern Tethys (Mesogea) persisting between Anatolia and Africa-Arabia until middle-late Miocene. Consequently, collision may have started later and northward

Jean Chorowicz; Pascal Luxey; Nikos Lyberis; Jose Cavalho; Jean-Francois Parrot; Tekin Yurur; Niyazi Gundogdu

1994-01-01

21

Direct Isolation of Satellite Cells for Skeletal Muscle Regeneration  

Microsoft Academic Search

Muscle satellite cells contribute to muscle regeneration. We have used a Pax3GFP\\/+ mouse line to directly isolate (Pax3)(green fluorescent protein)-expressing muscle satellite cells, by flow cytometry from adult skeletal muscles, as a homogeneous population of small, nongranular, Pax7+, CD34+, CD45-, Sca1- cells. The flow cytometry parameters thus established enabled us to isolate satellite cells from wild-type muscles. Such cells, grafted

Didier Montarras; Jennifer Morgan; Charlotte Collins; Frédéric Relaix; Stéphane Zaffran; Ana Cumano; Terence Partridge; Margaret Buckingham

2005-01-01

22

Satellites  

SciTech Connect

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.

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

1986-01-01

23

Donor Satellite Cell Engraftment is Significantly Augmented When the Host Niche is Preserved and Endogenous Satellite Cells are Incapacitated  

PubMed Central

Stem cell transplantation is already in clinical practice for certain genetic diseases and is a promising therapy for dystrophic muscle. We used the mdx mouse model of Duchenne muscular dystrophy to investigate the effect of the host satellite cell niche on the contribution of donor muscle stem cells (satellite cells) to muscle regeneration. We found that incapacitation of the host satellite cells and preservation of the muscle niche promote donor satellite cell contribution to muscle regeneration and functional reconstitution of the satellite cell compartment. But, if the host niche is not promptly refilled, or is filled by competent host satellite cells, it becomes nonfunctional and donor engraftment is negligible. Application of this regimen to aged host muscles also promotes efficient regeneration from aged donor satellite cells. In contrast, if the niche is destroyed, yet host satellite cells remain proliferation-competent, donor-derived engraftment is trivial. Thus preservation of the satellite cell niche, concomitant with functional impairment of the majority of satellite cells within dystrophic human muscles, may improve the efficiency of stem cell therapy. Stem Cells2012;30:1971–1984

Boldrin, Luisa; Neal, Alice; Zammit, Peter S; Muntoni, Francesco; Morgan, Jennifer E

2012-01-01

24

Activation of muscle satellite cells in single-fiber cultures  

Microsoft Academic Search

Satellite stem cell activation is the process by which quiescent precursor cells resident on muscle fibers are recruited to cycle and move. Two processes are reported to affect satellite cell activation. In vivo, nitric oxide (NO) produced by NO synthase in fibers (NOS-I?) promotes activation. In cell cultures, hepatocyte growth factor (HGF) is the major activating factor isolated from crushed

Judy Anderson; Orest Pilipowicz

2002-01-01

25

Water quality determination of Küçükçekmece Lake, Turkey by using multispectral satellite data.  

PubMed

This study focuses on the analysis of the Landsat-5 TM + SPOT-Pan (1992), IRS-1C/D LISS + Pan (2000), and Landsat-5 TM (2006) satellite images that reflect the drastic land use/land cover changes in the Küçükçekmece Lake region, Istanbul. Landsat-5 TM satellite data dated 2006 was used for mapping water quality. A multiple regression analysis was carried out between the unitless planetary reflectance values derived from the satellite image and in situ water quality parameters chlorophyll a, total phosphorus, total nitrogen, turbidity, and biological and chemical oxygen demand measured at a number of stations homogenously distributed over the lake surface. The results of this study provided valuable information to local administrators on the water quality of Küçükçekmece Lake, which is a large water resource of the Istanbul Metropolitan Area. Results also show that such a methodology structured by use of reflectance values provided from satellite imagery, in situ water quality measurements, and basin land use/land cover characteristics obtained from images can serve as a powerful and rapid monitoring tool for the drinking water basins that suffer from rapid urbanization and pollution, all around the world. PMID:19882091

Alparslan, Erhan; Coskun, Gonca; Alganci, Ugur

2009-11-01

26

Hesr1 and Hesr3 are essential to generate undifferentiated quiescent satellite cells and to maintain satellite cell numbers  

PubMed Central

Satellite cells, which are skeletal muscle stem cells, divide to provide new myonuclei to growing muscle fibers during postnatal development, and then are maintained in an undifferentiated quiescent state in adult skeletal muscle. This state is considered to be essential for the maintenance of satellite cells, but their molecular regulation is unknown. We show that Hesr1 (Hey1) and Hesr3 (Heyl) (which are known Notch target genes) are expressed simultaneously in skeletal muscle only in satellite cells. In Hesr1 and Hesr3 single-knockout mice, no obvious abnormalities of satellite cells or muscle regenerative potentials are observed. However, the generation of undifferentiated quiescent satellite cells is impaired during postnatal development in Hesr1/3 double-knockout mice. As a result, myogenic (MyoD and myogenin) and proliferative (Ki67) proteins are expressed in adult satellite cells. Consistent with the in vivo results, Hesr1/3-null myoblasts generate very few Pax7+ MyoD– undifferentiated cells in vitro. Furthermore, the satellite cell number gradually decreases in Hesr1/3 double-knockout mice even after it has stabilized in control mice, and an age-dependent regeneration defect is observed. In vivo results suggest that premature differentiation, but not cell death, is the reason for the reduced number of satellite cells in Hesr1/3 double-knockout mice. These results indicate that Hesr1 and Hesr3 are essential for the generation of adult satellite cells and for the maintenance of skeletal muscle homeostasis.

Fukada, So-ichiro; Yamaguchi, Masahiko; Kokubo, Hiroki; Ogawa, Ryo; Uezumi, Akiyoshi; Yoneda, Tomohiro; Matev, Miroslav M.; Motohashi, Norio; Ito, Takahito; Zolkiewska, Anna; Johnson, Randy L.; Saga, Yumiko; Miyagoe-Suzuki, Yuko; Tsujikawa, Kazutake; Takeda, Shin'ichi; Yamamoto, Hiroshi

2011-01-01

27

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

PubMed

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

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

2011-01-28

28

Influence of Growth Factors on Poultry Myogenic Satellite Cells  

Microsoft Academic Search

Skeletal muscle development in avian and mammalian embryos depends on the proliferation, differentiation, and fusion of embryonic myoblasts. During the late fetal period and following birth or hatching, myogenic satellite cells are responsible for this developmental function. Satellite cells, which are found adjacent to existing skeletal muscle fibers fuse with these fibers and their nuclei direct the synthesis of new

DOUGLAS C. MCFARLAND

29

Hesr1 and Hesr3 are essential to generate undifferentiated quiescent satellite cells and to maintain satellite cell numbers.  

PubMed

Satellite cells, which are skeletal muscle stem cells, divide to provide new myonuclei to growing muscle fibers during postnatal development, and then are maintained in an undifferentiated quiescent state in adult skeletal muscle. This state is considered to be essential for the maintenance of satellite cells, but their molecular regulation is unknown. We show that Hesr1 (Hey1) and Hesr3 (Heyl) (which are known Notch target genes) are expressed simultaneously in skeletal muscle only in satellite cells. In Hesr1 and Hesr3 single-knockout mice, no obvious abnormalities of satellite cells or muscle regenerative potentials are observed. However, the generation of undifferentiated quiescent satellite cells is impaired during postnatal development in Hesr1/3 double-knockout mice. As a result, myogenic (MyoD and myogenin) and proliferative (Ki67) proteins are expressed in adult satellite cells. Consistent with the in vivo results, Hesr1/3-null myoblasts generate very few Pax7(+) MyoD(-) undifferentiated cells in vitro. Furthermore, the satellite cell number gradually decreases in Hesr1/3 double-knockout mice even after it has stabilized in control mice, and an age-dependent regeneration defect is observed. In vivo results suggest that premature differentiation, but not cell death, is the reason for the reduced number of satellite cells in Hesr1/3 double-knockout mice. These results indicate that Hesr1 and Hesr3 are essential for the generation of adult satellite cells and for the maintenance of skeletal muscle homeostasis. PMID:21989910

Fukada, So-ichiro; Yamaguchi, Masahiko; Kokubo, Hiroki; Ogawa, Ryo; Uezumi, Akiyoshi; Yoneda, Tomohiro; Matev, Miroslav M; Motohashi, Norio; Ito, Takahito; Zolkiewska, Anna; Johnson, Randy L; Saga, Yumiko; Miyagoe-Suzuki, Yuko; Tsujikawa, Kazutake; Takeda, Shin'ichi; Yamamoto, Hiroshi

2011-11-01

30

Skeletal muscle satellite cells cultured in simulated microgravity  

Microsoft Academic Search

Summary  Satellite cells are postnatal myoblasts responsible for providing additional nuclei to growing or regenerating muscle cells.\\u000a 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\\u000a muscle development are limited by the two-dimensional (2-D) confines of the culture dish. Limiting proliferation

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

1997-01-01

31

The effect of syndecan-4 and glypican-1 expression on age-related changes in myogenic satellite cell proliferation, differentiation, and fibroblast growth factor 2 responsiveness.  

PubMed

Satellite cells are multipotential stem cells responsible for muscle growth and regeneration. Satellite cell proliferation, differentiation, and responsiveness to fibroblast growth factor 2 (FGF2) is, in part, regulated by the heparan sulfate proteoglycans syndecan-4 and glypican-1. Syndecan-4 and glypican-1 expression declines with satellite cell age and may be associated with decreased satellite cell activity. The objective of the current study was to determine if overexpression of syndecan-4 and glypican-1 would increase proliferation, differentiation and FGF2 responsiveness in satellite cells isolated from pectoralis major muscle from 16-wk-old turkeys. Overexpression of syndecan-4 and glypican-1 did not have a significant effect on proliferation and differentiation in 1d, 7wk, and 16wk satellite cells, and did not affect FGF2 responsiveness during proliferation. Expression of syndecan-4 and glypican-1 increased differentiation at 48h in 1d, 7wk, and 16wk cells treated with FGF2. Expression of myogenic regulatory factors MyoD, myogenin, and MRF4 was affected by the overexpression of syndecan-4 and glypican-1. However, changes in myogenic regulatory factor expression did not have a significant effect on proliferation or differentiation. These data demonstrate that syndecan-4 and glypican-1 are likely not directly associated with the age related decrease in satellite cell activity. PMID:24036479

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

2013-09-12

32

Distinct origins and genetic programs of head muscle satellite cells  

PubMed Central

Summary Adult skeletal muscle possesses a remarkable regenerative capacity, due to the presence of satellite cells, adult muscle stem cells. We used fate-mapping techniques in avian and mouse models to show that trunk (Pax3+) and cranial (MesP1+) skeletal muscle and satellite cells derive from separate genetic lineages. Similar lineage heterogeneity is seen within the head musculature and satellite cells, due to their shared, heterogenic embryonic origins. Lineage tracing experiments with Isl1Cre mice demonstrated the robust contribution of Isl1+ cells to distinct jaw muscle-derived satellite cells. Transplantation of myofiber-associated Isl1-derived satellite cells into damaged limb muscle contributed to muscle regeneration. In vitro experiments demonstrated the cardiogenic nature of cranial- but not trunk-derived satellite cells. Finally, overexpression of Isl1 in the branchiomeric muscles of chick embryos inhibited skeletal muscle differentiation in vitro and in vivo, suggesting that this gene plays a role in the specification of cardiovascular and skeletal muscle stem cell progenitors.

Harel, Itamar; Nathan, Elisha; Tirosh-Finkel, Libbat; Zigdon, Hila; Guimaraes-Camboa, Nuno; Evans, Sylvia M.; Tzahor, Eldad

2010-01-01

33

The muscle satellite cell at 50: the formative years  

PubMed Central

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.

2011-01-01

34

Deployment of real-time satellite remote sensing infrastructure to support disaster mitigation: A NATO Science for Peace collaboration project with Research Universities in Turkey, Egypt and the USA  

Microsoft Academic Search

The authors delineate the specific roles of the research partner institutions from Turkey, Egypt and the USA, in planning and implementing the North Atlantic Treaty Organization (NATO) Science for Peace sponsored Kamal Ewida Earth Observatory (KEEO), a network of real-time satellite remote sensing ground stations, being established over the next three years in Egypt, with a tracking station for polar

Gülay Altay; Okan Ersoy; Magdy Abdel Wahab; Gamal El Afandi; Mohammed Shokr; Tarek El Ghazawi; Mohamed A. Mohamed; Belal Eleithy; Islam Abou El-Magd; Larry Biehl; Darion Grant; G. Rochon; S. Fall

2009-01-01

35

The frequency of tuberculosis in adult allogeneic stem cell transplant recipients in Turkey  

Microsoft Academic Search

In general, tuberculosis (Tb) is rarely seen in allogeneic stem cell transplant (alloSCT) recipients, but this observation has been challenged in developing countries such as Turkey, where Tb infection is more prevalent than in Europe and the US. In this retrospective study, we report on the incidence of Tb infections in 351 alloSCT recipients at 4 bone marrow transplantation units

Tulin Budak-Alpdogan; Yucel Tangün; Sevgi Kalayoglu-Besisik; Siret Ratip; Hamdi Akan; Zafer Baslar; Teoman Soysal; Mahmut Bayik; Haluk Koç

2000-01-01

36

Transdifferentiation of porcine satellite cells to adipoblasts with ciglitizone1  

Microsoft Academic Search

Ciglitizone, a class of thiazolidinedi- ones, acts as a potent activator of the adipose differenti- ation program in established preadipose cell lines. Thi- azolidinediones have also been investigated in diabetic patients and have been reported to act as peroxisome proliferator-activated receptor-? ligands. Intramuscu- lar adipogenesis or marbling through transdifferentia- tion of satellite cells in cattle was successfully con- ducted earlier.

N. K. Singh; H. S. Chae; I. H. Hwang; Y. M. Yoo; C. N. Ahn; S. H. Lee; H. J. Lee; H. J. Park; H. Y. Chung

2010-01-01

37

An Evaluation Regarding the Current Situation of Stem Cell Studies in Turkey  

Microsoft Academic Search

Turkey is in a parallel state to that of other countries for developments in stem cell research and practices. Nevertheless,\\u000a Turkish law has no regulations for stem cell practices. To define a legal framework for stem cell research, rules of general\\u000a content should be used as the starting point. In 2005 and 2006, a general regulation and guidelines on stem

Berna Arda; Ahmet Ac?duman

2009-01-01

38

Satellite cells in innervated and denervated muscles treated with clenbuterol.  

PubMed

The sympathomimetic agent, clenbuterol, induces a muscle-specific hypertrophy in both normal and catabolic muscle. Drug-induced hypertrophy is not generally associated with an increase in DNA content, thus the role of satellite cells in the response of soleus muscles from weanling rats is questioned. Following simultaneous sciatic section and administration of clenbuterol, responses are similar in innervated and denervated muscles after 4 days. Increased protein accretion in treated muscles is associated with evidence of satellite cell activation, but with little evidence of division. It is speculated that satellite cell production of growth factors may play an important role in the hypertrophic action of clenbuterol, and the clinical implications of the findings are discussed. PMID:1495507

Maltin, C A; Delday, M I

1992-08-01

39

The skeletal muscle satellite cell: stem cell or son of stem cell?  

Microsoft Academic Search

The concept of the adult tissue stem cell is fundamental to models of persistent renewal in functionally post-mitotic tissues. Although relatively ignored by stem cell biology, skeletal muscle is a prime example of an adult tissue that can generate terminally differentiated cells uniquely specialized to carry out tissue-specific functions. This capacity is attributed to satellite cells, a population of undifferentiated,

Peter S. Zammit; Jonathan R. Beauchamp

2001-01-01

40

Satellite I DNA in transformed rat cells  

Microsoft Academic Search

P93-50, a 93-basepair (bp) repetitive DNA sequence from rats, was hybridized to transformed sublines of rat endothelial origin. The sequence hybridized at or near the centromeres of most but not all chromosomes in two transformed cell lines and three single-cell derived cultures. The hybridization signal was also frequently present at the telomeres. These cell lines have a highly aberrant karyotype

Keith L. Sternes; Baldev K. Vig

1995-01-01

41

Electrical analysis of a hybrid photovoltaic-hydrogen\\/fuel cell energy system in Denizli, Turkey  

Microsoft Academic Search

In recent years, hybrid photovoltaic-hydrogen\\/fuel cell energy systems have been popular as energy production systems that are clean, environmental-friendly, modular, and independent from fossil fuels. In February 2007, a clean energy research facility consisting of a 5kWp photovoltaic system and a 2.4kWp hydrogen-fuel cell system was built to investigate these energy production technologies at Pamukkale University in Denizli, Turkey. In

Engin Cetin; Ahmet Yilanci; Yusuf Oner; Metin Colak; Ismail Kasikci; Harun K. Ozturk

2009-01-01

42

Stra13 regulates satellite cell activation by antagonizing Notch signaling  

PubMed Central

Satellite cells play a critical role in skeletal muscle regeneration in response to injury. Notch signaling is vital for satellite cell activation and myogenic precursor cell expansion but inhibits myogenic differentiation. Thus, precise spatial and temporal regulation of Notch activity is necessary for efficient muscle regeneration. We report that the basic helix-loop-helix transcription factor Stra13 modulates Notch signaling in regenerating muscle. Upon injury, Stra13?/? mice exhibit increased cellular proliferation, elevated Notch signaling, a striking regeneration defect characterized by degenerated myotubes, increased mononuclear cells, and fibrosis. Stra13?/? primary myoblasts also exhibit enhanced Notch activity, increased proliferation, and defective differentiation. Inhibition of Notch signaling ex vivo and in vivo ameliorates the phenotype of Stra13?/? mutants. We demonstrate in vitro that Stra13 antagonizes Notch activity and reverses the Notch-imposed inhibition of myogenesis. Thus, Stra13 plays an important role in postnatal myogenesis by attenuating Notch signaling to reduce myoblast proliferation and promote myogenic differentiation.

Sun, Hong; Li, Li; Vercherat, Cecile; Gulbagci, Neriman Tuba; Acharjee, Sujata; Li, Jiali; Chung, Teng-Kai; Thin, Tin Htwe; Taneja, Reshma

2007-01-01

43

Substrate elasticity affects bovine satellite cell activation kinetics in vitro.  

PubMed

Satellite cells support efficient postnatal skeletal muscle hypertrophy through fusion into the adjacent muscle fiber. Nuclear contribution allows for maintenance of the fiber myonuclear domain and proficient transcription of myogenic genes. Niche growth factors affect satellite cell biology; however, the interplay between fiber elasticity and microenvironment proteins remains largely unknown. The objective of the experiment was to examine the effects of hepatocyte growth factor (HGF) and surface elasticity on bovine satellite cell (BSC) activation kinetics in vitro. Young's elastic modulus was calculated for the semimembranosus (SM) and LM muscles of young bulls (5 d; n = 8) and adult cows (27 mo; n = 4) cattle. Results indicate that LM elasticity decreased (P < 0.05) with age; no difference in Young's modulus for the SM was noted. Bovine satellite cells were seeded atop polyacrylamide bioscaffolds with surface elasticities that mimic young bull and adult cow LM or traditional cultureware. Cells were maintained in low-serum media supplemented with 5 ng/mL HGF or vehicle only for 24 or 48 h. Activation was evaluated by proliferating cell nuclear antigen (PCNA) immunocytochemistry. Results indicate that BSC maintained on rigid surfaces were activated at 24 h and refractive to HGF supplementation. By contrast, fewer (P < 0.05) BSC had exited quiescence after 24 h of culture on surfaces reflective of either young bull (8.1 ± 1.7 kPa) or adult cow (14.6 ± 1.6 kPa) LM. Supplementation with HGF promoted activation of BSC cultured on bioscaffolds as measured by an increase (P < 0.05) in PCNA immunopositive cells. Culture on pliant surfaces affected neither activation kinetics nor numbers of Paired box 7 (Pax7) immunopositive muscle stem cells (P > 0.05). However, with increasing surface elasticity, an increase (P < 0.05) in the numbers of muscle progenitors was observed. These results confirm that biophysical and biochemical signals regulate BSC activation. PMID:23463548

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

2013-03-05

44

Regenerative fuel cell study for satellites in GEO orbit  

Microsoft Academic Search

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

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

1987-01-01

45

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

Microsoft Academic Search

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,

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

2009-01-01

46

Human Muscle Satellite Cells as Targets of Chikungunya Virus Infection  

PubMed Central

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.

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; Despres, Philippe; Gessain, Antoine; Ceccaldi, Pierre-Emmanuel

2007-01-01

47

The contribution of high resolution satellite images to the production of base-maps and cartographies for archaeological research in Turkey and Iraq  

NASA Astrophysics Data System (ADS)

The paper concerns the contribution of high resolution satellite images to the production of base-maps and cartographies for archaeological research, using both during field work and in GIS dedicated to Cultural Heritage. Particularly, some experiences conducted during researches on Turkish and Iraqi archaeological sites are presented, where the use of satellite images was necessary because of both large scale cartographies and aero-photogrammetrical photos are not available. In the case of archaeological surveys in Hierapolis of Phrygia (south-western Turkey) they provided a fundamental tool for the research on the ground and for the analysis and management of data in the archaeological GIS of the territory. Ikonos-2 and QuickBird-2 images were ortho-rectified with the use of GCPs (taken with a differential GPS) and with DEMs and DSMs processed thanks different remote sensing data, radar (SRTM) and optical (Ikonos-2 and ASTER stereo-pairs), for the creation of space-maps and the extraction of cartographical elements: these (hydrology, modern topography, field boundaries, archaeological remains and traces, etc.) were used with the aims of the creation of new maps for archaeological purpose (the orography was extracted from DEMs) and the update of the existing ones. In the case of some ancient sites studied for the contextualization of the objects showed in the Virtual Museum of Iraq, high resolution images of the same satellites (and of WorldView-1) were ortho-rectified without GPCs and used for the creation or the update of the archaeological maps (generally very old), on which plans of excavated structures, recent discoveries, and archaeological traces and paleo-environmental elements were geo-referenced.

Scardozzi, Giuseppe

2009-09-01

48

Immunological tolerance in chickens hatching from eggs injected with cell-associated herpesvirus of Turkey (HVT)  

Microsoft Academic Search

Cell-associated herpesvirus of turkeys (HVT) was inoculated in ovo at various stages of incubation. Chickens hatching from these eggs were tested for anti-HVT antibodies by several serologic procedures including enzyme-linked immunosorbent assay, indirect immunofluorescence assays, and western blot. Viremic chickens that remained free of detectable antibodies were considered tolerant to HVT. Chickens exposed to HVT at embryonation day 14 or

Y Zhang; J. M Sharma

2003-01-01

49

Versican, matrix Gla protein, and death-associated protein expression affect muscle satellite cell proliferation and differentiation.  

PubMed

Our previous transcriptional profiling study using a turkey skeletal muscle-specific oligonucleotide microarray revealed over 3,000 genes that were differentially expressed at 3 critical stages of muscle development: 18 d embryonic, 1 d posthatch, and 16 wk of age. The genes versican, matrix Gla protein (MGP), and death-associated protein (DAP) were selected to study for their potential effects on muscle satellite cell proliferation and differentiation, as their functions in other tissues are suggestive of possible key roles in the regulation of myogenesis and they are differentially expressed throughout muscle development in the turkey. Using small interfering RNA to knockdown the expression of these genes during proliferation and differentiation, each of the genes was found to differentially affect proliferation and differentiation. Versican and MGP predominantly affected proliferation with line effects, but later stages of differentiation were affected by the knockdown of versican and MGP. The underexpression of DAP inhibited myotube formation, which is a necessary stage in the development of muscle fibers. Without myotube development, muscle fiber formation will be inhibited or abolished. This is the first report that these genes with no previously documented functions with regard to muscle development play a critical role in muscle cell proliferation and differentiation. PMID:22802192

Velleman, S G; Sporer, K R B; Ernst, C W; Reed, K M; Strasburg, G M

2012-08-01

50

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

PubMed

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

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

2013-08-02

51

Pax7 is critical for the normal function of satellite cells in adult skeletal muscle.  

PubMed

Extensive analyses of mice carrying null mutations in paired box 7 (Pax7) have confirmed the progressive loss of the satellite cell lineage in skeletal muscle, resulting in severe muscle atrophy and death. A recent study using floxed alleles and tamoxifen-induced inactivation concluded that after 3 wk of age, Pax7 was entirely dispensable for satellite cell function. Here, we demonstrate that Pax7 is an absolute requirement for satellite cell function in adult skeletal muscle. Following Pax7 deletion, satellite cells and myoblasts exhibit cell-cycle arrest and dysregulation of myogenic regulatory factors. Maintenance of Pax7 deletion through continuous tamoxifen administration prevented regrowth of Pax7-expressing satellite cells and a profound muscle regeneration deficit that resembles the phenotype of skeletal muscle following genetically engineered ablation of satellite cells. Therefore, we conclude that Pax7 is essential for regulating the expansion and differentiation of satellite cells during both neonatal and adult myogenesis. PMID:24065826

von Maltzahn, Julia; Jones, Andrew E; Parks, Robin J; Rudnicki, Michael A

2013-09-24

52

Pax7 is critical for the normal function of satellite cells in adult skeletal muscle  

PubMed Central

Extensive analyses of mice carrying null mutations in paired box 7 (Pax7) have confirmed the progressive loss of the satellite cell lineage in skeletal muscle, resulting in severe muscle atrophy and death. A recent study using floxed alleles and tamoxifen-induced inactivation concluded that after 3 wk of age, Pax7 was entirely dispensable for satellite cell function. Here, we demonstrate that Pax7 is an absolute requirement for satellite cell function in adult skeletal muscle. Following Pax7 deletion, satellite cells and myoblasts exhibit cell-cycle arrest and dysregulation of myogenic regulatory factors. Maintenance of Pax7 deletion through continuous tamoxifen administration prevented regrowth of Pax7-expressing satellite cells and a profound muscle regeneration deficit that resembles the phenotype of skeletal muscle following genetically engineered ablation of satellite cells. Therefore, we conclude that Pax7 is essential for regulating the expansion and differentiation of satellite cells during both neonatal and adult myogenesis.

von Maltzahn, Julia; Jones, Andrew E.; Parks, Robin J.; Rudnicki, Michael A.

2013-01-01

53

Cell therapy and satellite centers: The cardiovascular cell therapy research network experience  

Microsoft Academic Search

Due to the changing population in patients with myocardial infarction, recruiting patients in clinical trials continues to challenge clinical investigators. The Cardiovascular Cell Therapy Research Network (CCTRN) chose to expand the reach and power of its recruitment effort by incorporating both referral and treatment satellite centers. Eight treatment satellites were successfully identified and they screened patients over a two year

Lemuel A. Moyé; Timothy D. Henry; Kenneth W. Baran; Judy Bettencourt; Barb Bruhn-Ding; Emily Caldwell; Jeffrey Chambers; Kelly Flood; Judy Francescon; Sherry Bowman; Casey Kappenman; Biswajit Kar; Charles Lambert; Jody LaRock; Amir Lerman; Stacey Mazzurco; Rakesh Prashad; Ganesh Raveendran; Daniel Simon; Lynette Westbrook; Robert D. Simari

2011-01-01

54

Analysis of Land Use Change and Urbanization in the Kucukcekmece Water Basin (Istanbul, Turkey) with Temporal Satellite Data using Remote Sensing and GIS  

PubMed Central

Accurate and timely information about land use and land cover (LULC) and its changes in urban areas are crucial for urban land management decision-making, ecosystem monitoring and urban planning. Also, monitoring and representation of urban sprawl and its effects on the LULC patterns and hydrological processes of an urbanized watershed is an essential part of water resource planning and management. This paper presents an image analysis study using multi temporal digital satellite imagery of LULC and changes in the Kucukcekmece Watershed (Metropolitan Istanbul, Turkey) from 1992 to 2006. The Kucukcekmece Basin includes portions of the Kucukcekmece District within the municipality of Istanbul so it faces a dramatic urbanization. An urban monitoring analysis approach was first used to implement a land cover classification. A change detection method controlled with ground truth information was then used to determine changes in land cover. During the study period, the variability and magnitude of hydrological components based on land-use patterns were cumulatively influenced by urban sprawl in the watershed. The proposed approach, which uses a combination of Remote Sensing (RS) and Geographical Information System (GIS) techniques, is an effective tool that enhances land-use monitoring, planning, and management of urbanized watersheds.

Coskun, H. Gonca; Alganci, Ugur; Usta, Gokce

2008-01-01

55

Can satellite glial cells be therapeutic targets for pain control?  

PubMed Central

Satellite glial cells (SGCs) undergo phenotypic changes and divide the following injury into a peripheral nerve. Nerve injury, also elicits an immune response and several antigen-presenting cells are found in close proximity to SGCs. Silencing SCG-specific molecules involved in intercellular transport (Connexin 43) or glutamate recycling (glutamine synthase) can dramatically alter nociceptive responses of normal and nerve-injured rats. Transducing SGCs with glutamic acid decarboxylase can produce analgesia in models of trigeminal pain. Taken together these data suggest that SGCs may play a role in the genesis or maintenance of pain and open a range of new possibilities for curing neuropathic pain.

JASMIN, LUC; VIT, JEAN-PHILIPPE; BHARGAVA, ADITI; OHARA, PETER T.

2011-01-01

56

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)

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 attention. In this paper results of such analysis will be presented which seem to confirm results independently achieved (unfortunately without their knowledge) by other authors applying a similar approach to EOS/MODIS data over California region.

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

2012-04-01

57

Pax7 Is Required for the Specification of Myogenic Satellite Cells  

Microsoft Academic Search

The paired box transcription factor Pax7 was isolated by representational difference analysis as a gene specifically expressed in cultured satellite cell-derived myoblasts. In situ hybridization revealed that Pax7 was also expressed in satellite cells residing in adult muscle. Cell culture and electron microscopic analysis revealed a complete absence of satellite cells in Pax7?\\/? skeletal muscle. Surprisingly, fluorescence-activated cell sorting analysis

Patrick Seale; Luc A. Sabourin; Adele Girgis-Gabardo; Ahmed Mansouri; Peter Gruss; Michael A. Rudnicki

2000-01-01

58

Compromised T-cell immunity in turkeys may lead to an unpredictable avian metapneumovirus vaccine response and variable protection against challenge  

Microsoft Academic Search

Avian metapneumovirus (aMPV) is an important respiratory pathogen of turkeys with considerable economic impact on poultry production. Although vaccination is widely used for the control of the disease, questions regarding vaccine safety and efficacy remain to be elucidated. This report describes the problems associated with reproducibility of the aMPV-vaccine response, comparing T-lymphocyte-compromised and T-cell-intact turkeys. In three consecutive experiments, turkeys

Dennis Rubbenstroth; Silke Rautenschlein

2010-01-01

59

Use of turkey red blood cells in the passive haemagglutination test for studying tetanus immunity*  

PubMed Central

Passive haemagglutination (HA) assays were performed using turkey red blood cells (TRBC-HA) on sera from normal healthy people, from normal people previously immunized against tetanus, and from tetanus patients receiving human antitetanus immunoglobulins. The TRBC-HA test was compared with haemagglutination assays using sheep red blood cells (SRBC-HA) and with the neutralization (NT) test, and was found to be more sensitive than the SRBC-HA test and showed good correlation with the NT test. While the SRBC-HA assay calls for adsorption of sheep red blood cell agglutinins from the sera to be tested, the use of turkey red blood cells does not require any such adsorption. In addition, the TRBC-HA assay can be performed in 40 minutes compared with 6 hours for the SRBC-HA assay. All these advantages make the TRBC-HA assay a more useful test for screening large numbers of sera in the evaluation of tetanus immunity of normal people and of patients with wounds when seen in the emergency room of hospitals.

Pitzurra, M.; Bistoni, F.; Pitzurra, L.; Marconi, P.

1983-01-01

60

BMP signalling permits population expansion by preventing premature myogenic differentiation in muscle satellite cells  

Microsoft Academic Search

Satellite cells are the resident stem cells of adult skeletal muscle, supplying myonuclei for homoeostasis, hypertrophy and repair. In this study, we have examined the role of bone morphogenetic protein (BMP) signalling in regulating satellite cell function. Activated satellite cells expressed BMP receptor type 1A (BMPR-1A\\/Alk-3) and contained phosphorylated Smad proteins, indicating that BMP signalling is operating during proliferation. Indeed,

Y Ono; F Calhabeu; J E Morgan; T Katagiri; H Amthor; P S Zammit

2011-01-01

61

Cell Therapy and Satellite Centers: The Cardiovascular Cell Therapy Research Network Experience  

PubMed Central

Due to the changing population in patients with myocardial infarction, recruiting patients in clinical trials continues to challenge clinical investigators. The Cardiovascular Cell Therapy Research Network (CCTRN) chose to expand the reach and power of its recruitment effort by incorporating both referral and treatment satellite centers. Eight treatment satellites were successfully identified and they screened patients over a two year period. The result of this effort was an increase in recruitment, with these treatment satellites contributing 30 percent of the patients to two of the three Network studies. The hurdles these satellite treatment centers faced and how they surmounted them provide instruction to clinical research groups eager to expand to satellite systems and to health care practitioners who are interested in taking part in multicenter clinical trials.

Moye, Lemuel; Henry, Timothy D.; Baran, Kenneth W.; Bettencourt, Judy; Bruhn-Ding, Barb; Caldwell, Emily; Chambers, Jeffrey; Flood, Kelly; Francescon, Judy; Bowman, Sherry; Kappenman, Casey; Kar, Biswajit; Lambert, Charles; LaRock, Jody; Lerman, Amir; Mazzurco, Stacey; Prashad, Rakesh; Raveendran, Ganesh; Simon, Daniel; Westbrook, Lynette; Simari, Robert D.

2011-01-01

62

Latency of Herpesvirus of Turkey and Marek's Disease Virus Genomes in a Chicken T-Lymphoblastoid Cell Line  

Microsoft Academic Search

SUMMARY The properties of latent herpesvirus of turkey (HVT) and Marek's disease virus (MDV) genomes have been studied in virus-non-producer MDCC-BOI(T) cells, a T-lymphoblastoid cell line derived from spleen cells of an HVT-vaccinated chicken. The numbers of the two virus genomes in BO 1 (T) cells remained stable at 1.6 to 1.8 HVT genome equivalents\\/cell and 3.4 to 3.8 MDV

KANJI HIRAI; KAZUYOSHI IKUTA; NORITOSHI KITAMOTO; SHIRO KATO

1981-01-01

63

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

PubMed Central

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.

2012-01-01

64

Genetic Background Affects Properties of Satellite Cells and mdx Phenotypes  

PubMed Central

Duchenne muscular dystrophy (DMD) is the most common lethal genetic disorder of children. The mdx (C57BL/10 background, C57BL/10-mdx) mouse is a widely used model of DMD, but the histopathological hallmarks of DMD, such as the smaller number of myofibers, accumulation of fat and fibrosis, and insufficient regeneration of myofibers, are not observed in adult C57BL/10-mdx except for in the diaphragm. In this study, we showed that DBA/2 mice exhibited decreased muscle weight, as well as lower myofiber numbers after repeated degeneration–regeneration cycles. Furthermore, the self-renewal efficiency of satellite cells of DBA/2 is lower than that of C57BL/6. Therefore, we produced a DBA/2-mdx strain by crossing DBA/2 and C57BL/10-mdx. The hind limb muscles of DBA/2-mdx mice exhibited lower muscle weight, fewer myofibers, and increased fat and fibrosis, in comparison with C57BL/10-mdx. Moreover, remarkable muscle weakness was observed in DBA/2-mdx. These results indicate that the DBA/2-mdx mouse is a more suitable model for DMD studies, and the efficient satellite cell self-renewal ability of C57BL/10-mdx might explain the difference in pathologies between humans and mice.

Fukada, So-ichiro; Morikawa, Daisuke; Yamamoto, Yukiko; Yoshida, Tokuyuki; Sumie, Noriaki; Yamaguchi, Masahiko; Ito, Takahito; Miyagoe-Suzuki, Yuko; Takeda, Shin'ichi; Tsujikawa, Kazutake; Yamamoto, Hiroshi

2010-01-01

65

Satellite association frequency and number of nucleoli depend on cell cycle duration and NOR-activity  

Microsoft Academic Search

In human lymphocyte cultures the frequencies of satellite associations in first, second, and third mitoses were investigated using the BUDR-method. A marked decrease of the association frequency with increasing numbers of cell cycles was found. The number of nucleoli seen in interphase is correlated with the satellite association frequency in the respective metaphase. Satellite association is positively correlated to Ag-staining

J. Sigmund; H. G. Schwarzacher; A. V. Mikelsaar

1979-01-01

66

Pathogenesis of type II avian adenovirus infection in turkeys: in vivo immune cell tropism and tissue distribution of the virus.  

PubMed Central

Hemorrhagic enteritis virus (HEV), a type II avian adenovirus, causes intestinal hemorrhages and immunosuppression in turkeys. In this study, we exposed turkeys to virulent HEV and examined fractionated spleen cells for the presence of viral DNA by in situ hybridization and amplification of DNA extracted from virus-infected cells by PCR. HEV replication was detected only in the immunoglobulin M-bearing B lymphocytes and macrophage-like cells but not in the CD4+ or CD8+ T lymphocytes. The inability to infect T cells distinguishes type II avian adenoviruses from lymphotropic mammalian adenoviruses which infect and replicate in T cells. Furthermore, these data suggested that HEV-induced immunosuppression in turkeys may be due to the effect of the virus on B lymphocytes and macrophages. We also examined tissue tropism of HEV by in situ hybridization conducted on sections of lymphoid and nonlymphoid tissues. Large numbers of HEV-positive cells were detected in spleen and cecal tonsils. Diminutive viral activity was present in the intestines, the principal site of HEV-induced pathology. Thus, intestinal pathology was not associated with local cytopathic viral replication. This result and our previous observation that cyclosporin A abrogated intestinal hemorrhaging in HEV-infected turkeys strongly suggested that intestinal lesion induced by this virus may be immune system mediated.

Suresh, M; Sharma, J M

1996-01-01

67

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

PubMed

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

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

2010-01-31

68

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

PubMed Central

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.

Danoviz, Maria Elena; Yablonka-Reuveni, Zipora

2012-01-01

69

Notch1-mediated signaling regulates proliferation of porcine satellite cells (PSCs).  

PubMed

Notch signaling is an evolutionarily conserved cell-cell communication mechanism involved in the regulation of cell proliferation, differentiation and fate decisions of mammalian cells. In the present study, we investigated the possible requirement for Notch signaling in the proliferation and differentiation of porcine satellite cells. We show that Notch1, 2 and 3 are expressed in cultured porcine satellite cells. Knock-down of NOTCH1, but not NOTCH2 and NOTCH3, decreases the proliferation of porcine satellite cells. In contrast, enhancement of NOTCH1 expression via treatment of porcine satellite cells with recombinant NF-?B increases the proliferation of porcine satellite cells. The alteration of porcine satellite cell proliferation is associated with significant changes in the expression of cell cycle related genes (cyclin B1, D1, D2, E1 and p21), myogenic regulatory factors (MyoD and myogenin) and the Notch effector Hes5. In addition, alteration of Notch1 expression in porcine satellite cells causes changes in the expression of GSK3?-3. Taken together, these findings suggest that of the four notch-related genes, Notch1is likely to be required for regulating the proliferation and therefore the maintenance of porcine satellite cells in vivo, and do so through activation of the Notch effector gene Hes5. PMID:23160004

Qin, Lili; Xu, Jian; Wu, Zhenfang; Zhang, Zhe; Li, Jiaqi; Wang, Chong; Long, Qiaoming

2012-11-13

70

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

PubMed

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

Akku?, Yeliz; Karacan, Yasemin; Göker, Hakan; Aksu, Salih

2010-11-10

71

GFAP immunoreactivity in trigeminal ganglion satellite cells after tooth injury in rats  

Microsoft Academic Search

Glial fibrillary acidic protein (GFAP) is a member of a heterogeneous group of intermediate filaments in glial cells of both the central and peripheral nervous systems. We demonstrate here that satellite cells in the trigeminal ganglion (TG) increase immunoreactivity (IR) for GFAP in response to dental injury. The satellite cell reaction was most often confined to the somatotopic region of

Jennifer L. Stephenson; Margaret R. Byers

1995-01-01

72

TALIN DISTRIBUTION DURING THE DIFFERENTIATION OF SATELLITE CELLS ISOLATED FROM RAT SKELETAL MUSCLE  

Microsoft Academic Search

Satellite cells (myogenic stem cells) dissociated from adult muscle tissue proliferate, fuse and form multinucleate myotubes when placed in culture. This study focused on the role of talin distribution during the differentiation of satellite cells. Talin plays a key role in anchoring actin filaments to integrins as well as to the plasma membrane in focal contacts. We demonstrated that there

EDYTA BRZÓSKA; EDYTA WRÓBEL; IWONA GRABOWSKA; JERZY MORACZEWSKI

2004-01-01

73

Hepatocyte growth factor activates quiescent skeletal muscle satellite cells in vitro.  

PubMed

The effect of hepatocyte growth factor (HGF) on the activation of quiescent rat skeletal muscle satellite cells was evaluated in vitro. Satellite cells from 9-month-old adult rats are quiescent in vivo and when cultured, display a protracted lag phase prior to division that is not present in satellite cells from neonatal or regenerating muscle. Under normal growth conditions, satellite cells divide for the first time between 42 and 60 hr. Hepatocyte growth factor increased proliferation in a dose-dependent fashion prior to 48 hr with half-maximal stimulation at approximately 3 ng/ml; in addition, heparin enhanced this activity. The time course of cyclin-D1 and proliferating cell nuclear antigen (PCNA) expression was accelerated in HGF-treated satellite cells, indicating that cells entered the cell cycle earlier. No significant effects on muscle-derived fibroblast proliferation was observed. The signalling receptor for HGF is the product of the c-met protooncogene, and rtPCR analysis of satellite cells 0-72 hr in culture demonstrated the presence of this message throughout this time period. The presence of c-met in quiescent satellite cells, the ability of HGF to stimulate precocious entry into the cell cycle, and the previously described localization of HGF message in regenerating muscle (Jennische et al., 1993) indicate that HGF could act as an activator of quiescent satellite cells in vivo. PMID:7593208

Allen, R E; Sheehan, S M; Taylor, R G; Kendall, T L; Rice, G M

1995-11-01

74

Atrial natriuretic peptide stimulates aldosterone production by turkey (Meleagris gallopavo) adrenal steroidogenic cells.  

PubMed

The inhibitory action of atrial natriuretic peptides (ANPs) on mammalian aldosterone synthesis is well documented. In addition, other work indicates that ANP and an analogue of its second messenger, 8-Br-cGMP, inhibit aldosterone production by chicken adrenal steroidogenic cells. However, the interaction between angiotensin II (AII) and ANP in the regulation of avian aldosterone production is poorly understood because chicken adrenal steroidogenic cells, the commonly used in vitro avian model, are comparatively unresponsive to AII. By contrast, turkey (Meleagris gallopavo) adrenal steroidogenic cells are sensitive to AII. Thus, in the present study, the action of ANPs and related peptides and their interaction with other stimulators of aldosterone production were investigated using freshly isolated and briefly cultured turkey adrenal steroidogenic cells. Surprisingly, several ANPs [rat (r), human (h), chicken (c)], and rat brain natriuretic peptide (rBNP) were as efficacious as [Ile5]AII for stimulating aldosterone production (2 hr) in freshly isolated cell suspensions but were less potent than [Ile5]AII (ED50 of ANPs approximately 5-10 nM; [Ile5]AII ED50 approximately 0.1 nM). In addition, chicken ANP enhanced maximal aldosterone production induced by [Ile5]AII (1 nM), K+ (25 mM), and hACTH-(1-39) (ACTH) (1 nM): maximal enhancement of the action of these secretagogues was +49%, +137% and +15%, respectively (P < 0.05; n = 3). Furthermore, other ANPs and related peptides [rBNP and bovine aldosterone secretion inhibiting factor (bASIF)] enhanced maximal [Ile5]AII-induced aldosterone production: the order of maximal enhancement was rBNP (+180%) > hANP/rANP (+50%) > bASIF (+25%) (P < 0.05; n = 3).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8536948

Kocsis, J F; McIlroy, P J; Carsia, R V

1995-09-01

75

Regulation of aldosteronogenesis in domestic turkey (Meleagris gallopavo) adrenal steroidogenic cells.  

PubMed

The hormonal and cationic regulation of aldosterone production by freshly isolated turkey (Meleagris gallopavo) adrenal steroidogenic cells was investigated. Angiotensin II (AII), ACTH [human ACTH-(1-39)], and K+ stimulated aldosterone production in a concentration-dependent manner albeit these agents exhibited considerable differences in lag time for the significant stimulation of aldosterone production over basal production. By contrast, Ca2+ was without effect except at a high concentration (10 mM). Although ACTH was more efficacious than AII, it had about one-third the potency of AII for stimulating aldosterone production. However, ACTH potentiated the maximal aldosterone response to AII [maximal enhancement (+499%) at 3 x 10(-10) M ACTH]. Extracellular K+ was an absolute requirement for AII-induced aldosterone production (threshold concentration = 3 mM), and maximal enhancement (+200%) occurred with 5 mM (a physiological concentration). Although extracellular Ca2+ was not an absolute requirement for inducible aldosterone production, it enhanced AII-induced aldosterone production in a concentration-dependent manner [maximal enhancement (+727%) at 3 mM], albeit it did not alter the half-maximal steroidogenic concentration (EC50) of AII. Ca2+ also enhanced maximal ACTH-induced aldosterone production but to a lesser extent (+96% with 1 mM Ca2+). However, Ca2+ dramatically enhanced ACTH potency (ED50) (nearly 100 times at 1 mM Ca2+). The acute augmentation of AII-induced aldosterone production by ACTH, K+, and Ca2+ was not accompanied by increases in the cellular concentration and affinity of AII receptors, suggesting that the agents acted at intracellular loci distal to the AII receptor. Several aspects of the present study with isolated turkey adrenal steroidogenic cells differ markedly from those of studies with isolated chicken (Gallus gallus domesticus) adrenal steroidogenic cells and mammalian zona glomerulosa cells, thus suggesting interclass and intraclass differences in homeothermic vertebrate adrenal steroidogenic regulation. PMID:7843558

Kocsis, J F; Boyette, M H; McIlroy, P J; Carsia, R V

1994-10-01

76

The effect of immunosuppression on protective immunity of turkey poults against infection with turkey coronavirus  

Microsoft Academic Search

The objective of the present study was to evaluate the protective effect of humoral and cellular immunities on turkeys infected with turkey coronavirus (TCV). Two trials were conducted with two separate hatches of turkey poults. Turkeys were experimentally immunosuppressed with cyclosporin A (CsA) or cyclophosphamide (CY) and infected with TCV. Prior to infection, treatment with CsA selectively suppressed T cell

Chien Chang Loa; Tsang Long Lin; Ching Ching Wu; Thomas Bryan; Tom Hooper; Donna Schrader

2002-01-01

77

Direct effects of the pathogenic mutation on satellite cell function in muscular dystrophy.  

PubMed

Skeletal muscle is maintained and repaired by resident stem cells called muscle satellite cells, but there is a gradual failure of this process during the progressive skeletal muscle weakness and wasting that characterises muscular dystrophies. The pathogenic mutation causes muscle wasting, but in conditions including Duchenne muscular dystrophy, the mutant gene is not expressed in satellite cells, and so muscle maintenance/repair is not directly affected. The chronic muscle wasting, however, produces an increasingly hostile micro-environment in dystrophic muscle. This probably combines with excessive satellite cell use to eventually culminate in an indirect failure of satellite cell-mediated myofibre repair. By contrast, in disorders such as Emery-Dreifuss muscular dystrophy, the pathogenic mutation not only instigates muscle wasting, but could also directly compromise satellite cell function, leading to less effective muscle homeostasis. This may again combine with excessive use and a hostile environment to further compromise satellite cell performance. Whichever the mechanism, the ultimate consequence of perturbed satellite cell activity is a chronic failure of myofibre maintenance in dystrophic muscle. Here, we review whether the pathogenic mutation can directly contribute to satellite cell dysfunction in a number of muscular dystrophies. PMID:20546725

Morgan, Jennifer E; Zammit, Peter S

2010-05-28

78

Satellite cell depletion does not inhibit adult skeletal muscle regrowth following unloading-induced atrophy  

PubMed Central

Resident muscle stem cells, known as satellite cells, are thought to be the main mediators of skeletal muscle plasticity. Satellite cells are activated, replicate, and fuse into existing muscle fibers in response to both muscle injury and mechanical load. It is generally well-accepted that satellite cells participate in postnatal growth, hypertrophy, and muscle regeneration following injury; however, their role in muscle regrowth following an atrophic stimulus remains equivocal. The current study employed a genetic mouse model (Pax7-DTA) that allowed for the effective depletion of >90% of satellite cells in adult muscle upon the administration of tamoxifen. Vehicle and tamoxifen-treated young adult female mice were either hindlimb suspended for 14 days to induce muscle atrophy or hindlimb suspended for 14 days followed by 14 days of reloading to allow regrowth, or they remained ambulatory for the duration of the experimental protocol. Additionally, 5-bromo-2?-deoxyuridine (BrdU) was added to the drinking water to track cell proliferation. Soleus muscle atrophy, as measured by whole muscle wet weight, fiber cross-sectional area, and single-fiber width, occurred in response to suspension and did not differ between satellite cell-depleted and control muscles. Furthermore, the depletion of satellite cells did not attenuate muscle mass or force recovery during the 14-day reloading period, suggesting that satellite cells are not required for muscle regrowth. Myonuclear number was not altered during either the suspension or the reloading period in soleus muscle fibers from vehicle-treated or satellite cell-depleted animals. Thus, myonuclear domain size was reduced following suspension due to decreased cytoplasmic volume and was completely restored following reloading, independent of the presence of satellite cells. These results provide convincing evidence that satellite cells are not required for muscle regrowth following atrophy and that, instead, the myonuclear domain size changes as myofibers adapt.

Jackson, Janna R.; Mula, Jyothi; Kirby, Tyler J.; Fry, Christopher S.; Lee, Jonah D.; Ubele, Margo F.; Campbell, Kenneth S.; McCarthy, John J.; Peterson, Charlotte A.

2012-01-01

79

Satellite cell depletion does not inhibit adult skeletal muscle regrowth following unloading-induced atrophy.  

PubMed

Resident muscle stem cells, known as satellite cells, are thought to be the main mediators of skeletal muscle plasticity. Satellite cells are activated, replicate, and fuse into existing muscle fibers in response to both muscle injury and mechanical load. It is generally well-accepted that satellite cells participate in postnatal growth, hypertrophy, and muscle regeneration following injury; however, their role in muscle regrowth following an atrophic stimulus remains equivocal. The current study employed a genetic mouse model (Pax7-DTA) that allowed for the effective depletion of >90% of satellite cells in adult muscle upon the administration of tamoxifen. Vehicle and tamoxifen-treated young adult female mice were either hindlimb suspended for 14 days to induce muscle atrophy or hindlimb suspended for 14 days followed by 14 days of reloading to allow regrowth, or they remained ambulatory for the duration of the experimental protocol. Additionally, 5-bromo-2'-deoxyuridine (BrdU) was added to the drinking water to track cell proliferation. Soleus muscle atrophy, as measured by whole muscle wet weight, fiber cross-sectional area, and single-fiber width, occurred in response to suspension and did not differ between satellite cell-depleted and control muscles. Furthermore, the depletion of satellite cells did not attenuate muscle mass or force recovery during the 14-day reloading period, suggesting that satellite cells are not required for muscle regrowth. Myonuclear number was not altered during either the suspension or the reloading period in soleus muscle fibers from vehicle-treated or satellite cell-depleted animals. Thus, myonuclear domain size was reduced following suspension due to decreased cytoplasmic volume and was completely restored following reloading, independent of the presence of satellite cells. These results provide convincing evidence that satellite cells are not required for muscle regrowth following atrophy and that, instead, the myonuclear domain size changes as myofibers adapt. PMID:22895262

Jackson, Janna R; Mula, Jyothi; Kirby, Tyler J; Fry, Christopher S; Lee, Jonah D; Ubele, Margo F; Campbell, Kenneth S; McCarthy, John J; Peterson, Charlotte A; Dupont-Versteegden, Esther E

2012-08-15

80

Increased nuclear proteins in muscle satellite cells in aged animals as compared to young growing animals  

Microsoft Academic Search

Evidence implies that satellite cells could play some limiting role in aged muscle undergoing repair or maintenance of mass, which is of potential clinical concern as this could contribute to sarcopenia. Further, insufficient information is available concerning the cellular mechanisms responsible for the lower rat satellite cell proliferation in old animals. Thus, it was hypothesized that the following proteins would

Shuichi Machida; Frank W. Booth

2004-01-01

81

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

PubMed Central

This study investigated the effects of voluntary wheel running on satellite cells in the rat plantaris muscle. Seventeen 5-week-old male Wistar rats were assigned to a control (n = 5) or training (n = 12) group. Each rat in the training group ran voluntarily in a running-wheel cage for 8 weeks. After the training period, the animals were anesthetized, and the plantaris muscles were removed, weighed, and analyzed immunohistochemically and biochemically. Although there were no significant differences in muscle weight or fiber area between the groups, the numbers of satellite cells and myonuclei per muscle fiber, percentage of satellite cells, and citrate synthase activity were significantly higher in the training group compared with the control group (p < 0.05). The percentage of satellite cells was also positively correlated with distance run in the training group (r = 0.61, p < 0.05). Voluntary running can induce an increase in the number of satellite cells without changing the mean fiber area in the rat plantaris muscle; this increase in satellite cell content is a function of distance run. Key points There is no study about the effect of voluntary running on satellite cells in the rat plantaris muscle. Voluntary running training causes an increase of citrate synthase activity in the rat plantaris muscle but does not affect muscle weight and mean fiber area in the rat plantaris muscle. Voluntary running can induce an increase in the number of satellite cells without hypertrophy of the rat plantaris muscle.

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

2009-01-01

82

Low-energy laser irradiation affects satellite cell proliferation and differentiation in vitro  

Microsoft Academic Search

Low-energy laser (He–Ne) irradiation was found to promote skeletal muscle regeneration in vivo. In this study, its effect on the proliferation and differentiation of satellite cells in vitro was evaluated. Primary rat satellite cells were irradiated for various time periods immediately after preparation, and thymidine incorporation was determined after 2 days in culture. Laser irradiation affected thymidine incorporation in a

Nadav Ben-Dov; Gavriella Shefer; Andrey Irinitchev; Anton Wernig; Uri Oron; Orna Halevy

1999-01-01

83

Activated Satellite Cells in Medial Rectus Muscles of Patients with Strabismus  

PubMed Central

PURPOSE The goal of this study was to determine whether the medial rectus muscles of patients with a history of medial rectus underaction or overaction show alterations in the process of satellite cell activation when compared with normal age-matched control muscles. METHODS Medial rectus muscles were obtained with consent from adult patients undergoing surgical resection due to medial rectus underaction or overaction and were prepared for histologic examination by fixation and paraffin embedding. Control muscles were obtained from cornea donor eyes of adults who had no history of strabismus or neuromuscular disease. Cross sections were obtained and stained immunohistochemically for the presence of activated satellite cells, as identified by MyoD immunoreactivity, and the presence of the total satellite cell population, as identified by Pax7 immunoreactivity. The percentages of MyoD- and Pax7-positive satellite cells per 100 myofibers in cross section were calculated. RESULTS As predicted from results in the literature, MyoD-positive satellite cells, indicative of activation, were present in both the control and resected muscles. In the underacting medial rectus muscles, the percentages of MyoD- and Pax7-positive satellite cells, based on the number of myofibers, were approximately twofold higher than the percentages in the control muscles. In the overacting medial rectus muscles, the percentage of MyoD-positive satellite cells was twofold less than in the control muscles, whereas the percentage of Pax7-positive satellite cells significantly increased compared with that in the control specimens. CONCLUSIONS The presence of an increased number of activated satellite cells in the resected underacting medial rectus muscles and the decreased numbers of activated satellite cells in the overacting muscles was unexpected. The upregulation in the number of MyoD-positive satellite cells in underacting muscles suggests that there is potential for successful upregulation of size in these muscles, as the cellular machinery for muscle repair and regeneration, the satellite cells, is retained and active in patients with medial rectus underaction. The decreased number of activated satellite cells in overacting MR muscle suggests that factors as yet unknown in these overacting muscles are able to affect the number of satellite cells and/or their responsiveness compared with normal age-matched control muscles. These hypotheses are currently being tested.

Antunes-Foschini, Rosalia S.; Miyashita, Denise; Bicas, Harley E. A.; McLoon, Linda K.

2011-01-01

84

Pax7-expressing satellite cells are indispensable for adult skeletal muscle regeneration.  

PubMed

Distinct cell populations with regenerative capacity have been reported to contribute to myofibres after skeletal muscle injury, including non-satellite cells as well as myogenic satellite cells. However, the relative contribution of these distinct cell types to skeletal muscle repair and homeostasis and the identity of adult muscle stem cells remain unknown. We generated a model for the conditional depletion of satellite cells by expressing a human diphtheria toxin receptor under control of the murine Pax7 locus. Intramuscular injection of diphtheria toxin during muscle homeostasis, or combined with muscle injury caused by myotoxins or exercise, led to a marked loss of muscle tissue and failure to regenerate skeletal muscle. Moreover, the muscle tissue became infiltrated by inflammatory cells and adipocytes. This localised loss of satellite cells was not compensated for endogenously by other cell types, but muscle regeneration was rescued after transplantation of adult Pax7(+) satellite cells alone. These findings indicate that other cell types with regenerative potential depend on the presence of the satellite cell population, and these observations have important implications for myopathic conditions and stem cell-based therapeutic approaches. PMID:21828093

Sambasivan, Ramkumar; Yao, Roseline; Kissenpfennig, Adrien; Van Wittenberghe, Laetitia; Paldi, Andràs; Gayraud-Morel, Barbara; Guenou, Hind; Malissen, Bernard; Tajbakhsh, Shahragim; Galy, Anne

2011-09-01

85

Reduced Satellite Cell Numbers and Myogenic Capacity in Aging Can Be Alleviated by Endurance Exercise  

Microsoft Academic Search

BackgroundMuscle regeneration depends on satellite cells, myogenic stem cells that reside on the myofiber surface. Reduced numbers and\\/or decreased myogenic aptitude of these cells may impede proper maintenance and contribute to the age-associated decline in muscle mass and repair capacity. Endurance exercise was shown to improve muscle performance; however, the direct impact on satellite cells in aging was not yet

Gabi Shefer; Gat Rauner; Zipora Yablonka-Reuveni; Dafna Benayahu

2010-01-01

86

Myostatin signals through Pax7 to regulate satellite cell self-renewal  

SciTech Connect

Myostatin, a Transforming Growth Factor-beta (TGF-{beta}) super-family member, has previously been shown to negatively regulate satellite cell activation and self-renewal. However, to date the mechanism behind Myostatin function in satellite cell biology is not known. Here we show that Myostatin signals via a Pax7-dependent mechanism to regulate satellite cell self-renewal. While excess Myostatin inhibited Pax7 expression via ERK1/2 signaling, an increase in Pax7 expression was observed following both genetic inactivation and functional antagonism of Myostatin. As a result, we show that either blocking or inactivating Myostatin enhances the partitioning of the fusion-incompetent self-renewed satellite cell lineage (high Pax7 expression, low MyoD expression) from the pool of actively proliferating myogenic precursor cells. Consistent with this result, over-expression of Pax7 in C2C12 myogenic cells resulted in increased self-renewal through a mechanism which slowed both myogenic proliferation and differentiation. Taken together, these results suggest that increased expression of Pax7 promotes satellite cell self-renewal, and furthermore Myostatin may control the process of satellite cell self-renewal through regulation of Pax7. Thus we speculate that, in addition to the intrinsic factors (such as Pax7), extrinsic factors both positive and negative in nature, will play a major role in determining the stemness of skeletal muscle satellite cells.

McFarlane, Craig [AgResearch, Functional Muscle Genomics, Hamilton (New Zealand); Department of Biological Sciences, University of Waikato, Hamilton (New Zealand); Hennebry, Alex; Thomas, Mark; Plummer, Erin [AgResearch, Functional Muscle Genomics, Hamilton (New Zealand); Ling, Nicholas [Department of Biological Sciences, University of Waikato, Hamilton (New Zealand); Sharma, Mridula [AgResearch, Functional Muscle Genomics, Hamilton (New Zealand); Kambadur, Ravi [AgResearch, Functional Muscle Genomics, Hamilton (New Zealand); School of Biological Sciences, Nanyang Technological University (Singapore)], E-mail: KRavi@ntu.edu.sg

2008-01-15

87

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

PubMed

The cellular basis for mammalian muscle regeneration has been an area of intense investigation over recent decades. The consensus is that a specialized self-renewing stem cell, termed the satellite cell, plays a major role during the process of regeneration in amniotes. How broadly this mechanism is deployed within the vertebrate phylogeny remains an open question. A lack of information on the role of cells analogous to the satellite cell in other vertebrate systems is even more unexpected given the fact that satellite cells were first designated in frogs. An intriguing aspect of this debate is that a number of amphibia and many fish species exhibit epimorphic regenerative processes in specific tissues, whereby regeneration occurs by the dedifferentiation of the damaged tissue, without deploying specialized stem cell populations analogous to satellite cells. Hence, it is feasible that a cellular process completely distinct from that deployed during mammalian muscle regeneration could operate in species capable of epimorphic regeneration. In this minireview, we examine the evidence for the broad phylogenetic distribution of satellite cells. We conclude that, in the vertebrates examined so far, epimorphosis does not appear to be deployed during muscle regeneration, and that analogous cells expressing similar marker genes to satellite cells appear to be deployed during the regenerative process. However, the functional definition of these cells as self-renewing muscle stem cells remains a final hurdle to the definition of the satellite cell as a generic vertebrate cell type. PMID:23607511

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

2013-05-24

88

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

PubMed

Skeletal muscle regeneration mainly depends on satellite cells, a population of resident muscle stem cells. However, our understanding of the molecular mechanisms underlying satellite cell activation is still largely undefined. Here, we show that Cripto, a regulator of early embryogenesis, is a novel regulator of muscle regeneration and satellite cell progression toward the myogenic lineage. Conditional inactivation of cripto in adult satellite cells compromises skeletal muscle regeneration, whereas gain of function of Cripto accelerates regeneration, leading to muscle hypertrophy. Moreover, we provide evidence that Cripto modulates myogenic cell determination and promotes proliferation by antagonizing the TGF-? ligand myostatin. Our data provide unique insights into the molecular and cellular basis of Cripto activity in skeletal muscle regeneration and raise previously undescribed implications for stem cell biology and regenerative medicine. PMID:23129614

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

2012-11-05

89

Reduced Satellite Cell Numbers and Myogenic Capacity in Aging Can Be Alleviated by Endurance Exercise  

PubMed Central

Background Muscle regeneration depends on satellite cells, myogenic stem cells that reside on the myofiber surface. Reduced numbers and/or decreased myogenic aptitude of these cells may impede proper maintenance and contribute to the age-associated decline in muscle mass and repair capacity. Endurance exercise was shown to improve muscle performance; however, the direct impact on satellite cells in aging was not yet thoroughly determined. Here, we focused on characterizing the effect of moderate-intensity endurance exercise on satellite cell, as possible means to attenuate adverse effects of aging. Young and old rats of both genders underwent 13 weeks of treadmill-running or remained sedentary. Methodology Gastrocnemius muscles were assessed for the effect of age, gender and exercise on satellite-cell numbers and myogenic capacity. Satellite cells were identified in freshly isolated myofibers based on Pax7 immunostaining (i.e., ex-vivo). The capacity of individual myofiber-associated cells to produce myogenic progeny was determined in clonal assays (in-vitro). We show an age-associated decrease in satellite-cell numbers and in the percent of myogenic clones in old sedentary rats. Upon exercise, there was an increase in myofibers that contain higher numbers of satellite cells in both young and old rats, and an increase in the percent of myogenic clones derived from old rats. Changes at the satellite cell level in old rats were accompanied with positive effects on the lean-to-fat Gast muscle composition and on spontaneous locomotion levels. The significance of these data is that they suggest that the endurance exercise-mediated boost in both satellite numbers and myogenic properties may improve myofiber maintenance in aging.

Shefer, Gabi; Rauner, Gat; Yablonka-Reuveni, Zipora; Benayahu, Dafna

2010-01-01

90

Neonatal Phosphate Nutrition Alters in Vivo and in Vitro Satellite Cell Activity in Pigs  

PubMed Central

Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO4) deficiency can alter satellite cell activity, however the role of neonatal PO4 nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW) were pair-fed liquid diets that were either PO4 adequate (0.9% total P), supra-adequate (1.2% total P) in PO4 requirement or deficient (0.7% total P) in PO4 content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured in vitro for 7 days to determine if PO4 nutrition alters their ability to proceed through their myogenic lineage. Dietary PO4 deficiency resulted in reduced (P < 0.05) sera PO4 and parathyroid hormone (PTH) concentrations, while supra-adequate dietary PO4 improved (P < 0.05) feed conversion efficiency as compared to the PO4 adequate group. In vivo satellite cell proliferation was reduced (P < 0.05) among the PO4 deficient pigs, and these cells had altered in vitro expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO4 nutrition for future lean growth potential is warranted.

Alexander, Lindsey S.; Seabolt, Brynn S.; Rhoads, Robert P.; Stahl, Chad H.

2012-01-01

91

Neonatal phosphate nutrition alters in vivo and in vitro satellite cell activity in pigs.  

PubMed

Satellite cell activity is necessary for postnatal skeletal muscle growth. Severe phosphate (PO(4)) deficiency can alter satellite cell activity, however the role of neonatal PO(4) nutrition on satellite cell biology remains obscure. Twenty-one piglets (1 day of age, 1.8 ± 0.2 kg BW) were pair-fed liquid diets that were either PO(4) adequate (0.9% total P), supra-adequate (1.2% total P) in PO(4) requirement or deficient (0.7% total P) in PO(4) content for 12 days. Body weight was recorded daily and blood samples collected every 6 days. At day 12, pigs were orally dosed with BrdU and 12 h later, satellite cells were isolated. Satellite cells were also cultured in vitro for 7 days to determine if PO(4) nutrition alters their ability to proceed through their myogenic lineage. Dietary PO(4) deficiency resulted in reduced (P < 0.05) sera PO(4) and parathyroid hormone (PTH) concentrations, while supra-adequate dietary PO(4) improved (P < 0.05) feed conversion efficiency as compared to the PO(4) adequate group. In vivo satellite cell proliferation was reduced (P < 0.05) among the PO(4) deficient pigs, and these cells had altered in vitro expression of markers of myogenic progression. Further work to better understand early nutritional programming of satellite cells and the potential benefits of emphasizing early PO(4) nutrition for future lean growth potential is warranted. PMID:22822445

Alexander, Lindsey S; Seabolt, Brynn S; Rhoads, Robert P; Stahl, Chad H

2012-05-31

92

Satellited 4q identified in amniotic fluid cells  

SciTech Connect

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.

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

1995-01-16

93

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

PubMed Central

Background Current methods of isolation of muscle satellite cells from different animal species are highly variable making inter-species comparisons problematic. This variation mainly stems from the use of different proteolytic enzymes to release the satellite cells from the muscle tissue (sometimes a single enzyme is used but often a combination of enzymes is preferred) and the different extracellular matrix proteins used to coat culture ware. In addition, isolation of satellite cells is frequently laborious and sometimes may require pre-plating of the cell preparation on uncoated flasks or Percoll centrifugation to remove contaminating fibroblasts. The methodology employed to isolate and culture satellite cells in vitro can critically determine the fusion of myoblasts into multi-nucleated myotubes. These terminally differentiated myotubes resemble mature myofibres in the muscle tissue in vivo, therefore optimal fusion is a keystone of in vitro muscle culture. Hence, a simple method of muscle satellite cell isolation and culture of different vertebrate species that can result in a high fusion rate is highly desirable. Results We demonstrate here a relatively simple and rapid method of isolating highly enriched muscle satellite cells from different avian and mammalian species. In brief, muscle tissue was mechanically dissociated, digested with a single enzyme (pronase), triturated with a 10-ml pipette, filtered and directly plated onto collagen coated flasks. Following this method and after optimization of the cell culture conditions, excellent fusion rates were achieved in the duck, chicken, horse and cow (with more than 50% cell fusion), and to a lesser extent pig, pointing to pronase as a highly suitable enzyme to release satellite cells from muscle tissue. Conclusions Our simplified method presents a quick and simple alternative to isolating highly enriched muscle satellite cell cultures which can subsequently rapidly differentiate into well developed primary myotubes. The use of the same isolation protocol allows better inter-species comparisons of muscle satellite cells. Of all the farm animal species investigated, harvested chicken muscle cells showed the highest percentage of muscle satellite cells, and equine muscle cells presented the highest fusion index, an impressive???77%. Porcine cells displayed the lowest amount of satellite cells but still achieved a modest fusion rate of???41%.

2012-01-01

94

Preliminary observations of satellite cells in undamaged fibres of the rat soleus muscle assaulted by a snake-venom toxin  

Microsoft Academic Search

Satellite cells were studied in the undamaged part of the rat soleus muscle rendered partially necrotic by a subcutaneous injection of notexin, the myotoxic toxin purified from the venom of the Australian snake Notechis scutatus scutatus. Nuclei of satellite cells were twice as numerous as in the controls, with a decreasing gradient in the number of satellite cells with distance

Catherine Klein-Ogus; John B. Harris

1983-01-01

95

Observations on ploidy of cells and on reproductive performance in parthenogenetic turkeys.  

PubMed

Using flow cytometry, the ploidy levels of parthenogenetic turkeys were quantified from blastodisc stage to adulthood. Eggs were collected from noninseminated hens of the Beltsville Small White flock, known for their high degree of parthenogenesis, and the blastodermal cells from developing embryos were compared with those of embryos produced by hens inseminated with semen from males of the same flock. Erythrocytes of parthenogens from Day 10 of incubation to 27 mo of age were also used for ploidy determination. Sperm and erythrocyte preparations from normal males of the above flock served as haploid and diploid standards, respectively. In parthenogenetically developing blastoderms, 40.3 +/- 14.5% of the cells were haploid and 48.9 +/- 11.9% diploid; blastoderms from fertilized eggs had no haploid cells. The haploid cell content of parthenogens declined from the blastodermal stage to adult life, with 1.9 +/- 2.3% at 10 to 20 d of embryonic development, 1.5 +/- 1.4% at 21 to 29 d of development, 1.4 +/- 2.6% at 4 wk posthatch, and 1.3 +/- 1.9% in adulthood, although changes between the 1st mo after hatch and adult stage were not significant. It is possible, therefore, that parthenogenetic embryos with a low proportion of haploid cells could be the ones that survive to Day 10 of development and beyond, whereas those with a higher proportion of haploid cells fail to develop. The semen volume of male parthenogens was significantly lower than that of normal males, although the concentration of spermatozoa and their fertilizing capacity did not vary significantly between groups, suggesting that the germ cells of these parthenogens are capable of normal meiosis and sperm maturation leading to a normal fertility. PMID:9776050

Cassar, G; John, T M; Etches, R J

1998-10-01

96

Vaccination against Marek's disease: Immunizing effect of purified turkey herpes virus and cellular membranes from infected cells  

Microsoft Academic Search

One-day-old chickens susceptible to Marek's disease were vaccinated with experimental vaccines prepared from purified turkey herpes virus (HVT), inactivated HVT preparations or a membrane fraction isolated from HTV-infected chicken embryo fibroblasts, respectively. Purified HVT was found to be as effective in immunization against Marek's disease as cell-associated virus. The specific mortality of chickens twice vaccinated with cellular membranes from HVT-infected

O.-R. Kaaden; B. Dietzschold; S. UeberschÄr

1974-01-01

97

BMP signalling permits population expansion by preventing premature myogenic differentiation in muscle satellite cells.  

PubMed

Satellite cells are the resident stem cells of adult skeletal muscle, supplying myonuclei for homoeostasis, hypertrophy and repair. In this study, we have examined the role of bone morphogenetic protein (BMP) signalling in regulating satellite cell function. Activated satellite cells expressed BMP receptor type 1A (BMPR-1A/Alk-3) and contained phosphorylated Smad proteins, indicating that BMP signalling is operating during proliferation. Indeed, exogenous BMP4 stimulated satellite cell division and inhibited myogenic differentiation. Conversely, interfering with the interactions between BMPs and their receptors by the addition of either the BMP antagonist Noggin or soluble BMPR-1A fragments, induced precocious differentiation. Similarly, blockade of BMP signalling by siRNA-mediated knockdown of BMPR-1A, disruption of the intracellular pathway by either Smad5 or Smad4 knockdown or inhibition of Smad1/5/8 phosphorylation with Dorsomorphin, also caused premature myogenic differentiation. BMP signalling acted to inhibit the upregulation of genes associated with differentiation, in part, through regulating Id1. As satellite cells differentiated, Noggin levels increased to antagonise BMP signalling, since Noggin knockdown enhanced proliferation and impeded myoblast fusion into large multinucleated myotubes. Finally, interference of normal BMP signalling after muscle damage in vivo perturbed the regenerative process, and resulted in smaller regenerated myofibres. In conclusion, BMP signalling operates during routine satellite cell function to help coordinate the balance between proliferation and differentiation, before Noggin is activated to antagonise BMPs and facilitate terminal differentiation. PMID:20689554

Ono, Y; Calhabeu, F; Morgan, J E; Katagiri, T; Amthor, H; Zammit, P S

2010-08-06

98

Myogenic Satellite Cell Proliferative and Differentiative Responses to Components of Common Oral Ergogenic Supplements  

Microsoft Academic Search

This study evaluated the ability of common ergogenic supplement components to alter satellite cell proliferative activity in vitro. Compounds studied were cinnamic acid, ferulic acid, L-glutathione, ?-hydroxybutyric acid, calcium-?-hydroxy-?-methylbutyrate monohydrate, DL-thioctic acid (?-lipoic acid), and ornithine ?-ketoglutarate. Satellite cells were exposed to different levels of ergogenic test compound for a specified amount of time and analyzed by counting mononucleated and

MELINDA E. FERNYHOUGH; DERI L. HELTERLINE; JAN L. VIERCK; MICHAEL V. DODSON; LUKE R. BUCCI; JEFF Feliciano

2004-01-01

99

Myostatin Suppression of Akirin1 Mediates Glucocorticoid-Induced Satellite Cell Dysfunction  

PubMed Central

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.

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

2013-01-01

100

Monitoring the changing position of coastlines using aerial and satellite image data: an example from the eastern coast of Trabzon, Turkey  

Microsoft Academic Search

Coastline mapping and coastline change detection are critical issues for safe navigation, coastal resource management, coastal\\u000a environmental protection, and sustainable coastal development and planning. Changes in the shape of coastline may fundamentally\\u000a affect the environment of the coastal zone. This may be caused by natural processes and\\/or human activities. Over the past\\u000a 30 years, the coastal sites in Turkey have

Faik Ahmet Sesli; Fevzi Karsli; Ismail Colkesen; Nihat Akyol

2009-01-01

101

Pediatric oncology in Turkey.  

PubMed

The survival of children with cancer has increased dramatically in the last decades, as a result of advances in diagnosis, treatment and supportive care. Each year in Turkey, 2500-3000 new childhood cancer cases are expected. According to the Turkish Pediatric Oncology Group and Turkish Pediatric Hematology Societies Registry, about 2000 new pediatric cancer cases are reported each year. The population in Turkey is relatively young. One fourth of the population is younger than 15 years of age. According to childhood mortality, cancer is the fourth cause of death (7.2%) after infections, cardiac deaths and accidents. The major cancers in children in Turkey are leukemia (31%), lymphoma (19%), central nervous system (CNS) neoplasms (13%), neuroblastomas (7%), bone tumors (6.1%), soft tissue sarcomas (6%), followed by renal tumors, germ cell tumors, retinoblastoma, carcinomas-epithelial neoplasms, hepatic tumors and others. Lymphomas rank second in frequency as in many developing countries in contrast to West Europe or USA, where CNS neoplasms rank second in frequency. The seven-year survival rate in children with malignancies in Turkey is 65.8%. The history of modern Pediatric Oncology in Turkey dates back to the 1970's. Pediatric Oncology has been accepted as a subspecialty in Turkey since 1983. Pediatric Oncologists are all well trained and dedicated. All costs for the diagnosis and treatment of children with cancer is covered by the government. Education and infrastructure for palliative care needs improvement. PMID:22357143

Kebudi, Rejin

2012-03-01

102

Commitment of Satellite Cells Expressing the Calcium Channel ?2?1 Subunit to the Muscle Lineage  

PubMed Central

Satellite cells can maintain or repair muscle because they possess stem cell properties, making them a valuable option for cell therapy. However, cell transplants into skeletal muscle of patients with muscular dystrophy are limited by donor cell attachment, migration, and survival in the host tissue. Cells used for therapy are selected based on specific markers present in the plasma membrane. Although many markers have been identified, there is a need to find a marker that is expressed at different states in satellite cells, activated, quiescent, or differentiated cell. Furthermore, the marker has to be present in human tissue. Recently we reported that the plasma membrane ?2?1 protein is involved in cell attachment and migration in myoblasts. The ?2?1 subunit forms a part of the L-type voltage-dependent calcium channel in adult skeletal muscle. We found that the ?2?1 subunit is expressed in the majority of newly isolated satellite cells and that it appears earlier than the ?1 subunits and at higher levels than the ? or ? subunits. We also found that those cells that expressed ?2?1 would differentiate into muscle cells. This evidence indicates that the ?2?1 may be used as a marker of satellite cells that will differentiate into muscle.

Tamayo, Tammy; Grajales, Liliana; Garcia, Jesus

2012-01-01

103

Myf5 expression during fetal myogenesis defines the developmental progenitors of adult satellite cells.  

PubMed

Myf5 is a member of the muscle-specific determination genes and plays a critical role in skeletal muscle development. Whereas the expression of Myf5 during embryonic and fetal myogenesis has been extensively studied, its expression in progenitors that will ultimately give rise to adult satellite cells, the stem cells responsible for muscle repair, is still largely unexplored. To investigate this aspect, we have generated a mouse strain carrying a CreER coding sequence in the Myf5 locus. In this strain, Tamoxifen-inducible Cre activity parallels endogenous Myf5 expression. Combining Myf5(CreER) and Cre reporter alleles, we were able to evaluate the contribution of cells expressing Myf5 at distinct developmental stages to the pool of satellite cells in adult hindlimb muscles. Although it was possible to trace back the origin of some rare satellite cells to a subpopulation of Myf5(+ve) progenitors in the limb buds at the late embryonic stage (?E12), a significant number of satellite cells arise from cells which expressed Myf5 for the first time at the fetal stage (?E15). These studies provide direct evidence that adult satellite cells derive from progenitors that first express the myogenic determination gene Myf5 during fetal stages of myogenesis. PMID:23639729

Biressi, Stefano; Bjornson, Christopher R R; Carlig, Poppy M M; Nishijo, Koichi; Keller, Charles; Rando, Thomas A

2013-04-29

104

Role of satellite cells in muscle growth and maintenance of muscle mass.  

PubMed

Changes in muscle mass may result from changes in protein turnover, reflecting the balance between protein synthesis and protein degradation, and changes in cell turnover, reflecting the balance between myonuclear accretion and myonuclear loss. Myonuclear accretion, i.e. increase in the number of myonuclei within the muscle fibers, takes place via proliferation and fusion of satellite cells, myogenic stem cells associated to skeletal muscle fibers and involved in muscle regeneration. In developing muscle, satellite cells undergo extensive proliferation and most of them fuse with myofibers, thus contributing to the increase in myonuclei during early postnatal stages. A similar process is induced in adult skeletal muscle by functional overload and exercise. In contrast, satellite cells and myonuclei may undergo apoptosis during muscle atrophy, although it is debated whether myonuclear loss occurs in atrophying muscle. An increase in myofiber size can also occur by changes in protein turnover without satellite cell activation, e.g. in late phases of postnatal development or in some models of muscle hypertrophy. The relative role of protein turnover and cell turnover in muscle adaptation and in the establishment of functional muscle hypertrophy remains to be established. The identification of the signaling pathways mediating satellite cell activation may provide therapeutic targets for combating muscle wasting in a variety of pathological conditions, including cancer cachexia, renal and cardiac failure, neuromuscular diseases, as well as aging sarcopenia. PMID:22621743

Pallafacchina, G; Blaauw, B; Schiaffino, S

2012-05-21

105

Pericytes resident in postnatal skeletal muscle differentiate into muscle fibres and generate satellite cells  

Microsoft Academic Search

Skeletal muscle fibres form by fusion of mesoderm progenitors called myoblasts. After birth, muscle fibres do not increase in number but continue to grow in size because of fusion of satellite cells, the postnatal myogenic cells, responsible for muscle growth and regeneration. Numerous studies suggest that, on transplantation, non-myogenic cells also may contribute to muscle regeneration. However, there is currently

A. Dellavalle; G. Maroli; D. Covarello; E. Azzoni; A. Innocenzi; L. Perani; S. Antonini; R. Sambasivan; S. Brunelli; S. Tajbakhsh; G. Cossu

2011-01-01

106

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

PubMed Central

Despite the widespread consumption of nonsteroidal anti-inflammatory drugs (NSAIDs), the influence of these drugs on muscle satellite cells is not fully understood. The aim of the present study was to investigate the effect of a local NSAID infusion on satellite cells after unaccustomed eccentric exercise in vivo in human skeletal muscle. Eight young healthy males performed 200 maximal eccentric contractions with each leg. An NSAID was infused via a microdialysis catheter into the vastus lateralis muscle of one leg (NSAID leg) before, during, and for 4.5 h after exercise, with the other leg working as a control (unblocked leg). Muscle biopsies were collected before and 8 days after exercise. Changes in satellite cells and inflammatory cell numbers were investigated by immunohistochemistry. Satellite cells were identified using antibodies against neural cell adhesion molecule and Pax7. The number of Pax7+ cells per myofiber was increased by 96% on day 8 after exercise in the unblocked leg (0.14 ± 0.04, mean ± SE) compared with the prevalue (0.07 ± 0.02, P < 0.05), whereas the number of Pax7+ cells was unchanged in the leg muscles exposed to the NSAID (0.07 ± 0.01). The number of inflammatory cells (CD68+ or CD16+ cells) was not significantly increased in either of the legs 8 days after exercise and was unaffected by the NSAID. The main finding in the present study was that the NSAID infusion for 7.5 h during the exercise day suppressed the exercise-induced increase in the number of satellite cells 8 days after exercise. These results suggest that NSAIDs negatively affect satellite cell activity after unaccustomed eccentric exercise.

Langberg, H.; Helmark, I. C.; Skovgaard, D.; Andersen, L. L.; Kjaer, M.; Mackey, A. L.

2009-01-01

107

Recent progress in satellite cell/myoblast engraftment - relevance for therapy  

PubMed Central

There is currently no cure for muscular dystrophies, although several promising strategies are in basic and clinical research. One such strategy is cell transplantation with satellite cells (or their myoblast progeny) to repair damaged muscle and provide dystrophin protein with the aim of preventing subsequent myofibre degeneration and repopulating the stem cell niche for future use. The present review aims to cover recent advances in satellite cell/myoblast therapy and to discuss the challenges that remain for it to become a realistic therapy.

Briggs, Deborah; Morgan, Jennifer E

2013-01-01

108

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

PubMed Central

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.

Shefer, Gabi; Yablonka-Reuveni, Zipora

2012-01-01

109

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

Microsoft Academic Search

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)

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

2010-01-01

110

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

PubMed Central

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.

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

111

Brain-derived Neurotrophic Factor Regulates Satellite Cell Differentiation and Skeltal Muscle Regeneration  

PubMed Central

In adult skeletal muscle, brain-derived neurotrophic factor (BDNF) is expressed in myogenic progenitors known as satellite cells. To functionally address the role of BDNF in muscle satellite cells and regeneration in vivo, we generated a mouse in which BDNF is specifically depleted from skeletal muscle cells. For comparative purposes, and to determine the specific role of muscle-derived BDNF, we also examined muscles of the complete BDNF?/? mouse. In both models, expression of the satellite cell marker Pax7 was significantly decreased. Furthermore, proliferation and differentiation of primary myoblasts was abnormal, exhibiting delayed induction of several markers of differentiation as well as decreased myotube size. Treatment with exogenous BDNF protein was sufficient to rescue normal gene expression and myotube size. Because satellite cells are responsible for postnatal growth and repair of skeletal muscle, we next examined whether regenerative capacity was compromised. After injury, BDNF-depleted muscle showed delayed expression of several molecular markers of regeneration, as well as delayed appearance of newly regenerated fibers. Recovery of wild-type BDNF levels was sufficient to restore normal regeneration. Together, these findings suggest that BDNF plays an important role in regulating satellite cell function and regeneration in vivo, particularly during early stages.

Clow, Charlene

2010-01-01

112

Evidence for functionally distinct subpopulations of steroidogenic cells in the domestic turkey (Meleagris gallopavo) adrenal gland.  

PubMed

A body of histological and functional evidence supports the hypothesis that there are functionally distinct subpopulations of steroidogenic cells comprising the avian adrenal gland. In the present study, we tested this hypothesis by evaluating the steroidogenic responses of density-dependent subpopulations of adrenal steroidogenic cells isolated from domestic turkeys fed either a high-normal (control) sodium diet (0.4% Na+) or a Na(+)-restricted diet (0.04% Na+) for 8 days, the latter to stimulate the activity or appearance of possible zona glomerulosa-like cells. Subpopulations were visually yet reproducibly determined by their density-dependent separation on a continuous density gradient of Percoll (45%). The subpopulations were arbitrarily ascribed as being either low-density or high-density adrenal steroidogenic cells [LDAC (p = 1.0350-1.0585 g/ml) and HDAC (p = 1.0590-1.0720 g/ml), respectively]. LDAC and HDAC comprised 95.2 and 4.8%, respectively, of the total number of adrenal steroidogenic cells isolated. The LDAC was further subdivided into three visually distinct subpopulations. The functional differences between the LDAC subpopulations is discussed but was less dramatic than the functional distinction between the HDAC subpopulation and the pooled LDAC subpopulations. Basal aldosterone production values between control LDAC and HDAC were equivalent. In addition, there were no differences in maximal aldosterone production between control LDAC and HDAC in response to [Ile5]angiotensin II (AII), the avian equivalent, [Val5]AII, K+ (as KCl), and that supported by exogenous corticosterone. However, maximal aldosterone production in response to human ACTH-(1-39) (ACTH) of the LDAC was 32% greater than that of the HDAC. Na+ restriction enhanced basal aldosterone production of the LDAC by 84% over the control LDAC. In addition, it enhanced maximal aldosterone production of the LDAC in response to AII peptides, K+, ACTH and that supported by corticosterone by 54, 164, 83, and 74%, respectively, over that of the control LDAC. However, Na+ restriction disproportionately enhanced basal aldosterone production of the HDAC by 348% over that of the control HDAC. In addition, with Na+ restriction, maximal aldosterone production of the HDAC in response to AII, K+, and ACTH and that supported by exogenous corticosterone was consistently greater than that of the LDAC. Moreover, with Na+ restriction, maximal aldosterone production of the HDAC in response to AII peptides and K+ was increased over that of the control HDAC to a greater extent than was maximal aldosterone production in response to ACTH and that supported by corticosterone (% enhancement over control was as follows: AII peptides, 502%; K+, 668%; ACTH, 273%; corticosterone, 183%).(ABSTRACT TRUNCATED AT 400 WORDS) PMID:7781965

Kocsis, J F; Lamm, E T; McIlroy, P J; Scanes, C G; Carsia, R V

1995-04-01

113

Plasmacyte-reticulum cell satellitism in multiple myeloma associated with amyloidosis  

Microsoft Academic Search

A novel morphological feature is described in a patient with myeloma and associated amyloidosis: characteristic clustering (satellitism) of neoplastic plasma cells around macrophages in bone marrow aspirates. Although described in myeloma cell culture, as far as is known, this is the first description of this phenomenon in a patient. This unique association may partly explain the origin of amyloid deposition

T S Pillay; G Sayers; A R Bird; P Jacobs

1992-01-01

114

Short? and long?term stability studies on four lyophilised and one cell?associated turkey herpesvirus vaccines against marek's disease of chickens  

Microsoft Academic Search

One cell?associated and four lyophilised turkey herpesvirus (HVT) vaccines of different manufacturers were investigated comparatively in respect of the stability of their infectivity. All titrations were performed in primary chicken embryo fibroblast cell cultures and repeated seven times. The obtained data were computerised and statistically analysed.The long term stability study employed vaccine ampoules containing only lyophilised HVT. After appropriate storage

O. Siegmann; E. F. Kaleta; P. Schindler

1980-01-01

115

Abortive myogenesis in denervated skeletal muscle: differentiative properties of satellite cells, their migration, and block of terminal differentiation  

Microsoft Academic Search

Little is known about the biological properties of myogenic satellite cells during postdenervation muscle atrophy. The present study investigated the differentiative capacity of satellite cells and their involvement in the compensatory regenerative process in long-term denervated rat muscle. Electron microscopy and immunocytochemical labeling of muscle tissue 1–18 months following denervation demonstrated that despite activation of satellite cells, myogenesis in denervated muscle

Andrei B. Borisov; Eduard I. Dedkov; Bruce M. Carlson

2005-01-01

116

Electrical stimulation influences satellite cell proliferation and apoptosis in unloading-induced muscle atrophy in mice.  

PubMed

Muscle atrophy caused by disuse is accompanied by adverse physiological and functional consequences. Satellite cells are the primary source of skeletal muscle regeneration. Satellite cell dysfunction, as a result of impaired proliferative potential and/or increased apoptosis, is thought to be one of the causes contributing to the decreased muscle regeneration capacity in atrophy. We have previously shown that electrical stimulation improved satellite cell dysfunction. Here we test whether electrical stimulation can also enhance satellite cell proliferative potential as well as suppress apoptotic cell death in disuse-induced muscle atrophy. Eight-week-old male BALB/c mice were subjected to a 14-day hindlimb unloading procedure. During that period, one limb (HU-ES) received electrical stimulation (frequency: 20 Hz; duration: 3 h, twice daily) while the contralateral limb served as control (HU). Immunohistochemistry and western blotting techniques were used to characterize specific proteins in cell proliferation and apoptosis. The HU-ES soleus muscles showed significant improvement in muscle mass, cross-sectional area, and peak tetanic force relative to the HU limb (p<0.05). The satellite cell proliferative activity as detected within the BrdU+/Pax7+ population was significantly higher (p<0.05). The apoptotic myonuclei (detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) and the apoptotic satellite cells (detected by cleaved Poly [ADP-ribose] polymerase co-labeled with Pax7) were reduced (p<0.05) in the HU-ES limb. Furthermore the apoptosis-inducing factor and cleaved caspase-3 were down-regulated while the anti-apoptotic Bcl-2 protein was up-regulated (p<0.05), in the HU-ES limb. These findings suggest that the electrical stimulation paradigm provides an effective stimulus to rescue the loss of myonuclei and satellite cells in disuse muscle atrophy, thus maintaining a viable satellite cell pool for subsequent muscle regeneration. Optimization of stimulation parameters may enhance the outcome of the intervention. PMID:22253929

Guo, Bao-Sheng; Cheung, Kwok-Kuen; Yeung, Simon S; Zhang, Bao-Ting; Yeung, Ella W

2012-01-12

117

Expression of Cd34 and Myf5 Defines the Majority of Quiescent Adult Skeletal Muscle Satellite Cells  

Microsoft Academic Search

Skeletal muscle is one of a several adult post- mitotic tissues that retain the capacity to regenerate. This relies on a population of quiescent precursors, termed satellite cells. Here we describe two novel markers of quiescent satellite cells: CD34, an established marker of hematopoietic stem cells, and Myf5, the earliest marker of myogenic commitment. CD34 1 ve myoblasts can be

Jonathan R. Beauchamp; Louise Heslop; David S. W. Yu; Shahragim Tajbakhsh; Robert G. Kelly; Anton Wernig; Margaret E. Buckingham; Terence A. Partridge; Peter S. Zammit

2000-01-01

118

Satellite cells express distinct patterns of myogenic proteins in immature skeletal muscle.  

PubMed

Satellite cells are the myogenic cells lying between the myofiber sarcolemma and basal lamina. The objective of this study was to determine the expression patterns of MyoD, myogenin, and Pax7 within the satellite cell population in the growing rat soleus and extensor digitorum longus (EDL) muscles. Secondly, the expression of the myogenic markers was also studied within the interstitial cell compartment and myonuclei. It was discovered that the soleus contained a higher number of Pax7, MyoD, or myogenin-positive nuclei compared with the EDL. Similarly, myogenin was expressed at a lower level in the myonuclei of the soleus compared with the EDL, and myogenin was expressed at a higher level in the interstitial compartment of the soleus compared with the EDL. When interstitial nuclei, myonuclei, and double-labeled nuclei were used in the estimate of the satellite cell population, it was discovered that approximately of 13% of the myofibers in a transverse section of the soleus muscle and 4.1% of EDL myofibers exhibit a labeled satellite cell nucleus. Overall, results from this study suggest that expression patterns of these markers vary predictably among muscles with different growth dynamics and phenotypic characteristics. PMID:17029285

Schultz, Edward; Chamberlain, Connie; McCormick, Kathleen M; Mozdziak, Paul E

2006-12-01

119

Isolation and Culture of Individual Myofibers and their Satellite Cells from Adult Skeletal Muscle  

PubMed Central

Muscle regeneration in the adult is performed by resident stem cells called satellite cells. Satellite cells are defined by their position between the basal lamina and the sarcolemma of each myofiber. Current knowledge of their behavior heavily relies on the use of the single myofiber isolation protocol. In 1985, Bischoff described a protocol to isolate single live fibers from the Flexor Digitorum Brevis (FDB) of adult rats with the goal to create an in vitro system in which the physical association between the myofiber and its stem cells is preserved 1. In 1995, Rosenblattmodified the Bischoff protocol such that myofibers are singly picked and handled separately after collagenase digestion instead of being isolated by gravity sedimentation 2, 3. The Rosenblatt or Bischoff protocol has since been adapted to different muscles, age or conditions 3-6. The single myofiber isolation technique is an indispensable tool due its unique advantages. First, in the single myofiber protocol, satellite cells are maintained beneath the basal lamina. This is a unique feature of the protocol as other techniques such as Fluorescence Activated Cell Sorting require chemical and mechanical tissue dissociation 7. Although the myofiber culture system cannot substitute for in vivo studies, it does offer an excellent platform to address relevant biological properties of muscle stem cells. Single myofibers can be cultured in standard plating conditions or in floating conditions. Satellite cells on floating myofibers are subjected to virtually no other influence than the myofiber environment. Substrate stiffness and coating have been shown to influence satellite cells' ability to regenerate muscles 8, 9 so being able to control each of these factors independently allows discrimination between niche-dependent and -independent responses. Different concentrations of serum have also been shown to have an effect on the transition from quiescence to activation. To preserve the quiescence state of its associated satellite cells, fibers should be kept in low serum medium 1-3. This is particularly useful when studying genes involved in the quiescence state. In serum rich medium, satellite cells quickly activate, proliferate, migrate and differentiate, thus mimicking the in vivo regenerative process 1-3. The system can be used to perform a variety of assays such as the testing of chemical inhibitors; ectopic expression of genes by virus delivery; oligonucleotide based gene knock-down or live imaging. This video article describes the protocol currently used in our laboratory to isolate single myofibers from the Extensor Digitorum Longus (EDL) muscle of adult mice (6-8 weeks old).

Pasut, Alessandra; Jones, Andrew E.; Rudnicki, Michael A.

2013-01-01

120

MASTR directs MyoD-dependent satellite cell differentiation during skeletal muscle regeneration  

PubMed Central

In response to skeletal muscle injury, satellite cells, which function as a myogenic stem cell population, become activated, expand through proliferation, and ultimately fuse with each other and with damaged myofibers to promote muscle regeneration. Here, we show that members of the Myocardin family of transcriptional coactivators, MASTR and MRTF-A, are up-regulated in satellite cells in response to skeletal muscle injury and muscular dystrophy. Global and satellite cell-specific deletion of MASTR in mice impairs skeletal muscle regeneration. This impairment is substantially greater when MRTF-A is also deleted and is due to aberrant differentiation and excessive proliferation of satellite cells. These abnormalities mimic those associated with genetic deletion of MyoD, a master regulator of myogenesis, which is down-regulated in the absence of MASTR and MRTF-A. Consistent with an essential role of MASTR in transcriptional regulation of MyoD expression, MASTR activates a muscle-specific postnatal MyoD enhancer through associations with MEF2 and members of the Myocardin family. Our results provide new insights into the genetic circuitry of muscle regeneration and identify MASTR as a central regulator of this process.

Mokalled, Mayssa H.; Johnson, Aaron N.; Creemers, Esther E.; Olson, Eric N.

2012-01-01

121

In vitro characterization of proliferation and differentiation of pig satellite cells.  

PubMed

Skeletal muscle contains various muscle fiber types exhibiting different contractile properties based on the myosin heavy chain (MyHC) isoform profile. Muscle fiber type composition is highly variable and influences growth performance and meat quality, but underlying mechanisms regulating fiber type composition remain poorly understood. The aim of the present work was to develop a model based on muscle satellite cell culture to further investigate the regulation of adult MyHC isoforms expression in pig skeletal muscle. Satellite cells were harvested from the mostly fast-twitch glycolytic longissimus (LM) and predominantly slow-twitch oxidative rhomboideus (RM) muscles of 6-week-old piglets. Satellite cells were allowed to proliferate up to 80% confluence, reached after 7 day of proliferation (D7), and then induced to differentiate. Kinetics of proliferation and differentiation were similar between muscles and more than 95% of the cells were myogenic (desmin positive) at D7 with a fusion index reaching 65 ± 9% after 4 day of differentiation. One-dimensional SDS polyacrylamide gel electrophoresis revealed that satellite cells from both muscles only expressed the embryonic and fetal MyHC isoforms in culture, without any of the adult MyHC isoforms that were expressed in vivo. Interestingly, triiodothyronine (T3) induced de novo expression of adult fast and ?-cardiac MyHC in vitro making our culture system a valuable tool to study de novo expression of adult MyHC isoforms and its regulation by intrinsic and/or extrinsic factors. PMID:23023068

Perruchot, Marie-Hélène; Ecolan, Patrick; Sorensen, Inge Lise; Oksbjerg, Niels; Lefaucheur, Louis

2012-09-27

122

Life cycle testing of sodium-sulfur satellite battery cells  

NASA Astrophysics Data System (ADS)

The performance characteristics of sodium-beta double prime alumina-sulfur (Na/S) cells are being investigated under quiescent conditions (with the only variables being charge/discharge rates and the depth-of-discharge) with the purpose of establishing a basis for predicting the cycle life of the Na/S cells. All Na/S cells demonstrated a cycle life useful for certain Air Force applications, with no cycle life dependence on the depth-of-discharge values. The failures of two cells (of a total of eight tested) after extended cycling seems to be best explained by internal short circuiting, indicating the importance of cell matching when building batteries.

Allen, D. M.; Dueber, R. E.; Fritts, D. H.

1985-12-01

123

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

PubMed Central

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.

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

2012-01-01

124

Increased Frequency of Activated Satellite Cells in Overacting Inferior Oblique Muscles from Humans  

Microsoft Academic Search

PURPOSE. Strabismus is an oculomotor disorder in which there is a misalignment of the visual axes of the eyes. Inferior oblique muscle (IOM) overaction is a common finding in comitant horizontal strabismus, but its origin is unclear. Recent studies have demonstrated that myogenic satellite cells (SCs) are still activated in adult extraocular muscles, with continuous myo- nuclear addition in normal

Rosalia M. S. Antunes-Foschini; Fernando S. Ramalho; Leandra N. Z. Ramalho; Harley E. A. Bicas

2006-01-01

125

Cycle-life testing of large-capacity lithium-ion cells in simulated satellite operation  

Microsoft Academic Search

We are conducting cycle-life testing of 10–100 Ah-class lithium-ion cells in a simulated satellite operation at the Japan Aerospace Exploration Agency (JAXA). This paper reviews the latest test results of these lithium-ion cells. Thus far, we have verified impressive life performance exceeding 30,000 cycles in a simulated low-earth-orbit (LEO) mode and 1800 cycles in a simulated geostationary-earth-orbit (GEO) mode for

Xianming Wang; Yoshitsugu Sone; Hitoshi Naito; Chisa Yamada; Go Segami; Koichi Kibe

2006-01-01

126

Regenerative fuel cell study for satellites in GEO orbit. Final contractor report  

Microsoft Academic Search

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

A. Levy; L. L. Vandine; J. K. Stedman

1987-01-01

127

Absence of CD34 on Murine Skeletal Muscle Satellite Cells Marks a Reversible State of Activation during Acute Injury  

PubMed Central

Background Skeletal muscle satellite cells are myogenic progenitors that reside on myofiber surface beneath the basal lamina. In recent years satellite cells have been identified and isolated based on their expression of CD34, a sialomucin surface receptor traditionally used as a marker of hematopoietic stem cells. Interestingly, a minority of satellite cells lacking CD34 has been described. Methodology/Principal Findings In order to elucidate the relationship between CD34+ and CD34- satellite cells we utilized fluorescence-activated cell sorting (FACS) to isolate each population for molecular analysis, culture and transplantation studies. Here we show that unless used in combination with ?7 integrin, CD34 alone is inadequate for purifying satellite cells. Furthermore, the absence of CD34 marks a reversible state of activation dependent on muscle injury. Conclusions/Significance Following acute injury CD34- cells become the major myogenic population whereas the percentage of CD34+ cells remains constant. In turn activated CD34- cells can reverse their activation to maintain the pool of CD34+ reserve cells. Such activation switching and maintenance of reserve pool suggests the satellite cell compartment is tightly regulated during muscle regeneration.

Ieronimakis, Nicholas; Balasundaram, Gayathri; Rainey, Sabrina; Srirangam, Kiran; Yablonka-Reuveni, Zipora; Reyes, Morayma

2010-01-01

128

Signal-dependent fra-2 regulation in skeletal muscle reserve and satellite cells  

PubMed Central

Activator protein-1 (AP-1) is a ubiquitous transcription factor that paradoxically also has some tissue-specific functions. In skeletal muscle cells, we document that the AP-1 subunit, Fra-2, is expressed in the resident stem cells (Pax7-positive satellite cells) and also in the analogous undifferentiated ‘reserve' cell population in myogenic cultures, but not in differentiated myofiber nuclei. Silencing of Fra-2 expression enhances the expression of differentiation markers such as muscle creatine kinase and myosin heavy chain, indicating a possible role of Fra-2 in undifferentiated myogenic progenitor cells. We observed that Fra-2 is a target of cytokine-mediated extracellular signal-regulated kinase-1/2 signaling in cultured muscle cells, and extensive mass spectrometry and mutational analysis identified S320 and T322 as regulators of Fra-2 protein stability. Interestingly, Fra-2 S320 phosphorylation occurs transiently in activated satellite cells and is extinguished in myogenin-positive differentiating cells. Thus, cytokine-mediated Fra-2 expression and stabilization is linked to regulation of myogenic progenitor cells having implications for the molecular regulation of adult muscle stem cells and skeletal muscle regeneration.

Alli, N S; Yang, E C; Miyake, T; Aziz, A; Collins-Hooper, H; Patel, K; McDermott, J C

2013-01-01

129

Signal-dependent fra-2 regulation in skeletal muscle reserve and satellite cells.  

PubMed

Activator protein-1 (AP-1) is a ubiquitous transcription factor that paradoxically also has some tissue-specific functions. In skeletal muscle cells, we document that the AP-1 subunit, Fra-2, is expressed in the resident stem cells (Pax7-positive satellite cells) and also in the analogous undifferentiated 'reserve' cell population in myogenic cultures, but not in differentiated myofiber nuclei. Silencing of Fra-2 expression enhances the expression of differentiation markers such as muscle creatine kinase and myosin heavy chain, indicating a possible role of Fra-2 in undifferentiated myogenic progenitor cells. We observed that Fra-2 is a target of cytokine-mediated extracellular signal-regulated kinase-1/2 signaling in cultured muscle cells, and extensive mass spectrometry and mutational analysis identified S320 and T322 as regulators of Fra-2 protein stability. Interestingly, Fra-2 S320 phosphorylation occurs transiently in activated satellite cells and is extinguished in myogenin-positive differentiating cells. Thus, cytokine-mediated Fra-2 expression and stabilization is linked to regulation of myogenic progenitor cells having implications for the molecular regulation of adult muscle stem cells and skeletal muscle regeneration. PMID:23807221

Alli, N S; Yang, E C; Miyake, T; Aziz, A; Collins-Hooper, H; Patel, K; McDermott, J C

2013-06-27

130

Imprinted genes and satellite Loci are differentially methylated in bovine somatic cell nuclear transfer clones.  

PubMed

Abstract In mammals, genome-wide epigenetic reprogramming systems exist in primordial germ cells and zygotes. These reprogramming systems play crucial roles in regulating genome functions during critical stages of embryonic development, and they confer the stability of gene expression during mammalian development. The frequent unexpected loss of progeny from somatic cell nuclear transfer (SCNT) is an ongoing problem. In this study, we used six cloned bovines (named NT-1 to NT-6), which were created by ear fibroblast nuclear transfer and displayed short life spans with multiple organ defects, as an experimental model. We focus here on three imprinted genes (IGF2, H19, and XIST) and four satellite loci (Satellite I, Satellite II, Art2, and VNTR) to investigate their methylation changes. The results revealed that aberrant methylation frequently occurred in the analyzed imprinted genes, but not in the satellite loci, of the cloned bovines. After the bovine fibroblast cells were treated with the 5-aza-2(')-deoxycytidine (5-Aza-dc) demethylation agent, the methylation percentages of the XIST and H19 putative differentially methylated region (DMR) were significantly decreased (XIST, p<0.01; H19, p<0.05) followed by an increase in their mRNA expression levels (p<0.01). Furthermore, we found that five short-lived cloned bovines (NT-1 to NT-5) exhibited more severe aberrant methylation changes in the three imprinted genes examined than the little longer-lived clone (NT-6) compared with wild-type (WT) cows. Our data suggest that the reprogramming of the methylation-controlled regions between the imprinted genes and satellite loci are differences and may be involved with additional mechanisms that need further elucidation. PMID:23961768

Shen, Chih-Jie; Lin, Chiao-Chieh; Shen, Perng-Chih; Cheng, Winston T K; Chen, Hsiao-Ling; Chang, Tsung-Chou; Liu, Shyh-Shyan; Chen, Chuan-Mu

2013-08-20

131

Human satellite progenitor cells for use in myofascial repair: isolation and characterization.  

PubMed

Current use of prosthetic meshes and implants for myofascial reconstruction has been associated with infectious complications, long-term failure, and dissatisfying cosmetic results. Our laboratory has developed a small animal model for ventral hernia repair, which uses progenitor cells isolated from a skeletal muscle biopsy. In the model, progenitor cells are expanded in vitro, seeded onto a nonimmunogenic, novel aligned scaffold of bovine collagen and placed into the defect as a living adjuvant to the innate repair mechanism. The purpose of the current investigation is to examine the feasibility of translating our current model to humans. As a necessary first step we present our study on the efficacy of isolating satellite cells from 9 human donor biopsies. We were able to successfully translate our progenitor cell isolation and culture protocols to a human model with some modifications. Specifically, we have isolated human satellite muscle cells, expanded them in culture, and manipulated these cells to differentiate into myotubes in vitro. Immunohistochemical analysis allowed the characterization of distinct progenitor cell cycle stages and quantification of approximate cell number. Furthermore, isolated cells were tracked via cytoplasmic nanocrystal labeling and observed using confocal microscopy. PMID:20407365

Logan, Melissa S; Propst, John T; Nottingham, James M; Goodwin, Richard L; Pabon, Diego F; Terracio, Louis; Yost, Michael J; Fann, Stephen A

2010-06-01

132

Satellite 2 demethylation induced by 5-azacytidine is associated with missegregation of chromosomes 1 and 16 in human somatic cells  

Microsoft Academic Search

Satellite sequences are an important part of the pericentromeric regions in mammalian genomes; they play a relevant role in chromosome stability and DNA hypomethylation of these sequences has been reported in ICF syndrome and in some cancers that are closely associated with chromosomal abnormalities. Epigenetic modifications of satellite sequences and their consequences have not been extensively studied in human cells.

Diddier Prada; Rodrigo González; Lisandro Sánchez; Clementina Castro; Eunice Fabián; Luis A. Herrera

133

Electrode structure analysis and surface characterization for lithium-ion cells simulated low-Earth-orbit satellite operation  

Microsoft Academic Search

Lithium-ion cells for satellite applications operate under a special condition, and are expected to behave differently from those for commercial purposes. To understand the performance-degradation mechanism of lithium-ion cells experienced cycle-life testing in a simulated low-Earth-orbit (LEO) satellite operation, we conducted the structure analysis and surface characterization of the aged LiCoO2 cathode and graphite anode obtained from a lithium-ion cell

Xianming Wang; Yoko Sakiyama; Yoshikazu Takahashi; Chisa Yamada; Hitoshi Naito; Go Segami; Toshiya Hironaka; Eiji Hayashi; Kouichi Kibe

2007-01-01

134

Concomitant increases in myonuclear and satellite cell content in female trapezius muscle following strength training  

Microsoft Academic Search

A skeletal muscle fibre maintains its cytoplasmic volume by means of hundreds of myonuclei distributed along its entire length.\\u000a Therefore it is hypothesised that changes in fibre size would involve modifications in myonuclear number. In this study, we\\u000a have examined whether 10 weeks of strength training can induce changes in the number of myonuclei and satellite cells in female\\u000a trapezius

Fawzi Kadi; Lars-Eric Thornell

2000-01-01

135

Commonly Consumed Oral Herbal Supplements Do Not Influence Satellite Cell Activity  

Microsoft Academic Search

This study evaluated the ability of common herbal components in ergogenic dietary supplements to alter satellite cell activity in vitro. Herbal compounds studied were banaba leaf extract (1?g· ml, 10?g· ml, 100?g· ml, 1mg· ml), foenugreek seed extract (1?g· ml, 10?g· ml, 100?g· ml, 1mg· ml), andCystoseira canariensis extract (10pg· ml, 1ng· ml, 100ng· ml, 10?g· ml, 100?g· ml, 1mg·

MELINDA E. FERNYHOUGH; JAN L. VIERCK; DERI L. HELTERLINE; MICHAEL V. DODSON; LUKE R. BUCCI; JEFF FELICIANO

2004-01-01

136

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

PubMed

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, ?1-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

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

2013-02-13

137

Inhibition of toll-like receptor 2-mediated NF-kappaB activation in Vero cells with herpesvirus of turkeys.  

PubMed

In a previous study, vaccination with a live bivalent vaccine consisting of herpesvirus of turkeys (HVT) and SB-1 was found to be associated with distinct cytokine expression patterns and the modulation of cytokine responses in the spleen. This vaccine could play a role in mediating protection against infection with the RB1B strain of Marek's disease virus. In the present study, vectors for chicken Toll-like receptor 1 (chTLR1) and 2 (chTLR2) expression were constructed and transfected into Vero cells. Nuclear factor kappa light-chain enhancer of activated B cell (NF-kappaB) activation was detected after HVT infection. Compared with normal Vero cells, NF-kappaB activation was significantly inhibited by HVT in Vero cells transfected with chTLR1-1, chTLR1-2, or both. The results demonstrate the significant characteristics of HVT in activating TLR2 signaling. chTLR1 plays a key role in TLR2 subfamily-mediated NF-kappaB inhibition after HVT infection. PMID:23901754

Yang, Qingli; Chen, Hao; Wei, Tianchao; Wei, Ping

2013-06-01

138

Porcine satellite cells are restricted to a phenotype resembling their muscle origin.  

PubMed

Muscles in most domestic animals differ in function and growth potential based largely on muscle fiber type composition. Though much is known about satellite cells (SC), information is limited regarding how populations of SC differ with muscle fiber type, especially in pigs. Therefore, the objective of this study was to isolate and culture SC from red (RST) and white (WST) portions of the semitendinosus muscle of neonatal and adult pigs and determine their capacity to proliferate, differentiate, and express various myosin heavy chain (MyHC) isoforms in vitro. Porcine satellite cells were isolated from RST and WST muscles of 6-wk-old and adult (>6-mo-old) pigs and cultured under standard conditions. Muscle from neonatal pigs yielded nearly 10 times more (P < 0.001) presumptive satellite cells as those from adult pigs, with fusion percentages close to 60% for the former. The RST yielded more (P < 0.001) SC per gram muscle compared to WST, 8.1 ± 0.2 × 10(4) cells versus 6.7 ± 0.1 × 10(4) cells/gram muscle in young pigs, and 9.7 ± 0.4 × 10(3) cells versus 5.5 ± 0.4 × 10(3) cells/gram muscle in adult pigs, respectively. Likewise, satellite cells from RST proliferated faster (P < 0.001) than those from WST across both ages, as indicated by a shorter cell doubling time, 18.6 ± 0.8 h versus 21.3 ± 0.9 h in young pigs, and 23.2 ± 0.7 h versus 26.7 ± 0.9 h in adult pigs, respectively. As a result of shorter times to confluence, satellite cells from RST also formed myotubes earlier than those SC originating from WST. Once induced, however, SC from WST differentiated and fused faster (P < 0.05) as evidenced by fusion percentage within the first 24 h, 41.6% versus 34.3%, respectively; but reached similar ultimate fusion percentages similar to WST by 48 h. Over 90% of MyHC expressed in maximally fused SC cultures from both RST and WST was restricted to the embryonic isoform. Type IIX MyHC mRNA was not detected in any culture. Myotube cultures from RST expressed more (P < 0.01) Type I MyHC isoform mRNA than those from WST, whereas those cultures from WST expressed more (P < 0.05) Type II (including Types IIA and IIB) MyHC transcripts. These data show SC cultures from porcine fast and slow muscles express MyHC profiles largely reflective of their muscle of origin and suggest satellite cells are partially restricted to a particular muscle phenotype in which they are juxtapositioned. Understanding the molecular nature of these intrinsic control mechanisms may lead to improved strategies for augmenting meat animal growth or muscle regeneration. PMID:23893979

Zhu, H; Park, S; Scheffler, J M; Kuang, S; Grant, A L; Gerrard, D E

2013-07-26

139

Defects in Glycosylation Impair Satellite Stem Cell Function and Niche Composition in the Muscles of the Dystrophic Largemyd Mouse  

PubMed Central

Abstract The dystrophin-associated glycoprotein complex (DGC) is found at the muscle fiber sarcolemma and forms an essential structural link between the basal lamina and internal cytoskeleton. In a set of muscular dystrophies known as the dystroglycanopathies, hypoglycosylation of the DGC component ?-dystroglycan results in reduced binding to basal lamina components, a loss in structural stability, and repeated cycles of muscle fiber degeneration and regeneration. The satellite cells are the key stem cells responsible for muscle repair and reside between the basal lamina and sarcolemma. In this study, we aimed to determine whether pathological changes associated with the dystroglycanopathies affect satellite cell function. In the Largemyd mouse dystroglycanopathy model, satellite cells are present in significantly greater numbers but display reduced proliferation on their native muscle fibers in vitro, compared with wild type. However, when removed from their fiber, proliferation in culture is restored to that of wild type. Immunohistochemical analysis of Largemyd muscle reveals alterations to the basal lamina and interstitium, including marked disorganization of laminin, upregulation of fibronectin and collagens. Proliferation and differentiation of wild-type satellite cells is impaired when cultured on substrates such as collagen and fibronectin, compared with laminins. When engrafted into irradiated tibialis anterior muscles of mdx-nude mice, wild-type satellite cells expanded on laminin contribute significantly more to muscle regeneration than those expanded on fibronectin. These results suggest that defects in ?-dystroglycan glycosylation are associated with an alteration in the satellite cell niche, and that regenerative potential in the dystroglycanopathies may be perturbed.

Ross, Jacob; Benn, Abigail; Jonuschies, Jacqueline; Boldrin, Luisa; Muntoni, Francesco; Hewitt, Jane E; Brown, Susan C; Morgan, Jennifer E

2012-01-01

140

Establishment of a variant type of turkey herpesvirus which releases cell-free virus into the culture medium in large quantities  

Microsoft Academic Search

Summary A variant turkey herpesvirus (HVT\\/VT) which releases 105.0 plaqueforming units per 0.1 ml of cell-free virus into the culture medium was established from the prototype HVT FC 126 strain (HVT\\/WT). Many enveloped and naked virions of HVT\\/VT but only naked virions of HVT\\/WT were found in the culture medium. By theHindIII restriction cleavage patterns, the HVT\\/VT DNAs were almost

S. Yachida; T. Kondo; K. Hirai; H. Izawa; T. Mikami

1986-01-01

141

Further characterisation of a variant type of turkey herpesvirus which releases large quantities of cell?free viruses into culture medium  

Microsoft Academic Search

A variant type of turkey herpesvirus (HVT\\/VT) which releases large quantities of cell?free virus into its culture medium was compared with the prototype of the FC 126 strain of HVT (HVT\\/WT) as to the biological and serological characteristics.The lack of replication?defective HVT\\/VT in chickens was considered to be due to the inability of the virus to infect and replicate in

Shunsuke Yachida; Yoshiyuki Hayashi; Hisao Izawa; Takeshi Mikami

1989-01-01

142

Most Virus-specific Polypeptides in Cells Productively Infected with Marek's Disease Virus or Herpesvirus of Turkeys Possess Cross-reactive Determinants  

Microsoft Academic Search

SUMMARY Most virus-specific polypeptides in cells productively infected with Marek's disease virus (MDV) or herpesvirus of turkeys (HVT) possess cross-reactive antigenic determinants, although the two viruses have very little DNA homology. The cross- reactivity appeared to be more evident when (35S)methionine-labelled polypeptides were immunoprecipitated than when the (3H)glucosamine-labeUed polypeptides were immunoprecipitated, suggesting that the glycoproteins of MDV and HVT may

KAZUYOSHI IKUTA; SHIGEHARU UEDA; SHIRO KATO; KANJI HIRAI

1983-01-01

143

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

NASA Astrophysics Data System (ADS)

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 hardware costs. In aggregate these factors can account for more than a 10% increase in the total system cost. Since the estimated total costs of proposed global coverage systems range from $1 Billion to $9 Billion, the availability of radiation hard solar cells could make a decisive difference in the selection of a particular constellation architecture.

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

1995-10-01

144

Satellite glial cell proliferation in the trigeminal ganglia after chronic constriction injury of the infraorbital nerve.  

PubMed

We have examined satellite glial cell (SGC) proliferation in trigeminal ganglia following chronic constriction injury of the infraorbital nerve. Using BrdU labeling combined with immunohistochemistry for SGC specific proteins we positively confirmed proliferating cells to be SGCs. Proliferation peaks at approximately 4 days after injury and dividing SGCs are preferentially located around neurons that are immunopositive for ATF-3, a marker of nerve injury. After nerve injury there is an increase GFAP expression in SGCs associated with both ATF-3 immunopositive and immunonegative neurons throughout the ganglia. SGCs also express the non-glial proteins, CD45 and CD163, which label resident macrophages and circulating leukocytes, respectively. In addition to SGCs, we found some Schwann cells, endothelial cells, resident macrophages, and circulating leukocytes were BrdU immunopositive. GLIA 2013;61:2000-2008. PMID:24123473

Donegan, Macayla; Kernisant, Melanie; Cua, Criselda; Jasmin, Luc; Ohara, Peter T

2013-10-03

145

Different central nervous system cell types display distinct and nonrandom arrangements of satellite DNA sequences.  

PubMed Central

Paraformaldehyde-fixed tissue from mouse cerebellum was hybridized with biotin-labeled satellite DNA for identification of centromeres. By using avidin-peroxidase conjugates, it was possible to define the nuclear position of centromeres at the ultrastructural level. Three-dimensional analysis of well-resolved centromere arrays were aided by computer reconstruction of serial sections. Different cell types displayed distinct, nonrandom centromere locations. In Purkinje neurons, the majority of detected sequences were clustered together around the central nucleolus, whereas in granule neurons, more numerous, dispersed centromere clusters were associated with the nuclear membrane. In Purkinje cells, peroxidase-labeled regions corresponded to dense heterochromatic aggregates were detected in Purkinje cells of several different species. These observations suggest that in these highly differentiated cells, the nuclear position of centromeres is maintained in evolution despite species differences in centromeric DNA sequence. Such defined ordering of centromeres may be integral to specific functional capacities. Images

Manuelidis, L

1984-01-01

146

Changes in mass and performance in rabbit muscles after muscle damage with or without transplantation of primary satellite cells.  

PubMed

Changes in morphology, metabolism, myosin heavy chain gene expression, and functional performances in damaged rabbit muscles with or without transplantation of primary satellite cells were investigated. For this purpose, we damaged bilaterally the fast muscle tibialis anterior (TA) with either 1.5 or 2.6 ml cardiotoxin 10(-5) M injections. Primary cultures of satellite cells were autotransplanted unilaterally 5 days after muscle degeneration. Two months postoperation, the masses of damaged TAs, with or without transplantation, were significantly larger than those of the controls. Furthermore, damaged transplanted muscles weighed significantly more than damaged muscles only. The increase in muscle mass was essentially due to increased fiber size. These results were independent of the quantity of cardiotoxin injected into the muscles. Maximal forces were similar in control and 2.6 ml damaged TAs with or without satellite cell transfer. In contrast, 1.5 ml damaged TAs showed a significant decrease in maximal forces that reached the level of controls after transplantation of satellite cells. Fatigue resistance was similar in control and 1.5 ml damaged TAs independently of satellite cell transfer. Fatigue index was significantly higher in 2.6 ml damaged muscles with or without cell transplantation. These changes could be explained in part by muscle metabolism, which shifted towards oxidative activities, and by gene expression of myosin heavy chain isoforms, which presented an increase in type IIa and a decrease in type I and IIb in all damaged muscles with or without cell transfer. Under our experimental conditions, these results show that muscle damage rather than satellite cell transplantation changes muscle metabolism, myosin heavy chain isoform gene expression, and, to a lesser extent, muscle contractile properties. In contrast, muscle weight and fiber size are increased both by muscle damage and by satellite cell transfer. PMID:12099640

Boubaker el Andalousi, Ramzi; Daussin, Paul-André; Micallef, Jean-Paul; Roux, Colette; Nougues, Jean; Chammas, Michel; Reyne, Yves; Bacou, Francis

2002-01-01

147

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

PubMed Central

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

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

2008-01-01

148

Restoration of muscle fibers and satellite cells after isogenic MSC transplantation with microdystrophin gene delivery.  

PubMed

Duchenne muscular dystrophy is the most prevalent inheritable muscle disease. Transplantation of autologous stem cells with gene direction is an ideal therapeutic approach for the disease. The current study aimed to investigate the restoration of myofibers in mdx mice after mdx bone marrow-derived mesenchymal stem cell (mMSC) transplantation with human microdystrophin delivery. Possible mechanisms of action were also studied. In our research, mMSCs were successfully transduced by retrovirus carrying a functional human microdystrophin gene. Transplantation of transduced mMSCs enabled persistent dystrophin restoration in the skeletal muscle of mdx mice up to the 12th week after transplantation. Simultaneous coexpression of human microdystrophin and desmin showed that implanted mMSCs are capable of long-term survival as muscle satellite cells. PMID:22321394

Feng, Shan-wei; Chen, Fei; Cao, Jiqing; Yu, Mei-juan; Liang, Ying-yin; Song, Xin-ming; Zhang, Cheng

2012-01-30

149

Release of Hepatocyte Growth Factor from Mechanically Stretched Skeletal Muscle Satellite Cells and Role of pH and Nitric Oxide  

Microsoft Academic Search

Application of mechanical stretch to cultured adult rat muscle satellite cells results in release of hepatocyte growth factor (HGF) and accelerated entry into the cell cycle. Stretch activation of cultured rat muscle satellite cells was observed only when medium pH was between 7.1 and 7.5, even though activation of satellite cells was accelerated by exogenous HGF over a pH range

Ryuichi Tatsumi; Akihito Hattori; Yoshihide Ikeuchi; Judy E. Anderson; Ronald E. Allen

2002-01-01

150

Turkey`s energy insecurity  

SciTech Connect

The economic boom underway throughout much of the developing world today is spurring a surge in energy markets the likes of which have not been seen since the 1960s. The International Energy Agency projects that developing countries` energy use will nearly double by 2010, and that their share of the world total will grow from the current 27 percent to 40 percent. While such figures can be seen as signs of progress, they bear seeds of danger as well. If the new demand is met mainly by fossil fuels, rising oil prices and spreading environmental damage could undermine the economic development that extended energy use is intended to trigger. Turkey is a country that epitomizes the dilemma. A cultural bridge between East and West, and a geographic one between oil producers and consumers, Turkey lies at the crossroads of the industrial and developing worlds. Occupying a territory more than twice the size of Germany or Japan, it has a population of 60 million - projected to reach 80 million by 2010 - and a rapidly industrializing economy. Yet, in its per capita income and energy use, it is closer to Brazil or Thailand than to its industrialized fellow members of the Organisation for Economic Co-operation and Development (OECD). This article looks both at the present energy supplies and needs of Turkey and its future energy supplies in terms of alternative energy resources such as sunlight and wind and increasing natural gas imports. Emphasis on the less expensive and technology intense energy would decrease the need to plan for the huge burdens of nuclear energy.

Tunali, O.

1995-07-01

151

The depletion of skeletal muscle satellite cells with age is concomitant with reduced capacity of single progenitors to produce reserve progeny  

PubMed Central

Satellite cells are myogenic progenitors residing on the myofiber surface that support skeletal muscle repair. We used mice in which satellite cells were detected by GFP expression driven by nestin gene regulatory elements to define age-related changes in both numbers of satellite cells that occupy hindlimb myofibers and their individual performance. We demonstrate a reduction in satellite cells per myofiber with age that is more prominent in females compared to males. Satellite cell loss also persists with age in myostatin-null mice regardless of increased muscle mass. Immunofluorescent analysis of isolated myofibers from nestin-GFP/Myf5nLacZ/+ mice reveals a decline with age in the number of satellite cells that express detectable levels of ?gal. Nestin-GFP expression typically diminishes in primary cultures of satellite cells as myogenic progeny proliferate and differentiate, but GFP subsequently reappears in the Pax7+ reserve population. Clonal analysis of sorted GFP+ satellite cells from hindlimb muscles shows heterogeneity in the extent of cell density and myotube formation among colonies. Reserve cells emerge primarily within high-density colonies, and the number of clones that produce reserve cells is reduced with age. Thus, satellite cell depletion with age could be attributed to a reduced capacity to generate a reserve population.

Day, Kenneth; Shefer, Gabi; Shearer, Andrew; Yablonka-Reuveni, Zipora

2010-01-01

152

Satellite Cells Senescence in Limb Muscle of Severe Patients with COPD  

PubMed Central

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

Theriault, Marie-Eve; Pare, Marie-Eve; Maltais, Francois; Debigare, Richard

2012-01-01

153

Forskolin-induced differentiation of BeWo cells stimulates increased tumor growth in the chorioallantoic membrane (CAM) of the turkey (Meleagris gallopavo) egg.  

PubMed

Invasiveness of BeWo cells has been assessed in a variety of assay systems including matrigel and mouse. At the same time BeWo cells are mostly used as model system for trophoblast fusion. Here we aimed to test the properties of BeWo cells in a combined approach. We forced BeWo cells to differentiate by culturing the cells in the presence of forskolin and then used these cells for invasion assays on the chorioallantoic membrane (CAM) of the turkey. The chorioallantoic membranes of turkey eggs were incubated with medium containing forskolin, BeWo cells cultured in medium alone, BeWo cells cultured in forskolin and washed, and BeWo cells cultured in forskolin and used directly for application. Suspensions were applied onto ten CAM per condition. For local tumor formation eggs were checked for tumor development every 24h macroscopically for up to 12 days and immunohistochemistry for cytokeratin 18 and Ki-67 were used for further analysis. Forskolin alone did not have any deleterious effect on the CAM. When the CAM was incubated with BeWo cells cultured in medium 40% of the eggs developed a macroscopically visible tumor. BeWo cells stimulated with forskolin and washed induced tumor growth in 50% of the eggs, while forskolin stimulated BeWo cells applied directly onto the CAM induced tumor growth in 70% of the eggs. Forced differentiation of BeWo cells by forskolin may lead to syncytial fusion in a plastic culture dish. Under the conditions used here, i.e. in direct contact to a living tissue, forskolin-induced differentiation of BeWo cells leads to an increase in tumor formation in the CAM. Thus BeWo cells may use signaling pathways to decide for both differentiation pathways similar to primary trophoblast depending on the environment. PMID:21440429

Schneider, Ralf; Borges, Marcus; Kadyrov, Mamed

2011-03-10

154

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

PubMed

Studies of the structural organization and functions of the cell body of a neuron (soma) and its surrounding satellite glial cells (SGCs) in sensory ganglia have led to the realization that SGCs actively participate in the information processing of sensory signals from afferent terminals to the spinal cord. SGCs use a variety ways to communicate with each other and with their enwrapped soma. Changes in this communication under injurious conditions often lead to abnormal pain conditions. "What are the mechanisms underlying the neuronal soma and SGC communication in sensory ganglia?" and "how do tissue or nerve injuries affect the communication?" are the main questions addressed in this review. GLIA 2013;61:1571-1581. PMID:23918214

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

2013-08-05

155

Satellite cells, myoblasts and other occasional myogenic progenitors: Possible origin, phenotypic features and role in muscle regeneration  

Microsoft Academic Search

In the vertebrate embryo, skeletal muscle originates from somites and is formed in discrete steps by different classes of progenitor cells. After myotome formation, embryonic myoblasts give rise to primary fibers in the embryo, while fetal myoblasts give rise to secondary fibers, initially smaller and surrounding primary fibers. Satellite cells appear underneath the newly formed basal lamina that develops around

Giulio Cossu; Stefano Biressi

2005-01-01

156

Isolation of nuclei from skeletal muscle satellite cells and myofibers for use in chromatin immunoprecipitation assays.  

PubMed

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

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

2012-01-01

157

Satellite 2 demethylation induced by 5-azacytidine is associated with missegregation of chromosomes 1 and 16 in human somatic cells.  

PubMed

Satellite sequences are an important part of the pericentromeric regions in mammalian genomes; they play a relevant role in chromosome stability and DNA hypomethylation of these sequences has been reported in ICF syndrome and in some cancers that are closely associated with chromosomal abnormalities. Epigenetic modifications of satellite sequences and their consequences have not been extensively studied in human cells. In the present work, we evaluated satellite 2 methylation patterns in human lymphocytes exposed to 5-azacytidine (5-azaC) and assessed the relationship between these patterns and chromosome missegregation. Human lymphocytes were exposed to 10?M 5-azaC for 24, 48, and 72h. Segregation errors were evaluated in binucleate cells using FISH against pericentromeric regions of chromosomes 1, 9, and 16. DNA methylation patterns were evaluated by immunodetection, and by bisulfite plus urea conversion and sequencing. We have identified that 5-azaC induced missegregation of chromosomes 1 and 16, which have highly methylated satellite 2, after 72h of exposure. Chromosome methylation patterns showed a notable decrease in pericentromeric methylation. Bisulfite conversion and sequencing analysis demonstrated demethylation of satellite 2 associated to 5-azaC exposure, principally after 72h of treatment. This change occurred in a non-specific pattern. Our study demonstrates an association between loss of satellite 2 DNA methylation and chromosome loss in human lymphocytes. PMID:22032830

Prada, Diddier; González, Rodrigo; Sánchez, Lisandro; Castro, Clementina; Fabián, Eunice; Herrera, Luis A

2011-10-20

158

Terrorism Effects on Turkey.  

National Technical Information Service (NTIS)

The purpose of this study is to add to the understanding of the dangers of international terrorism as those affect Turkey. Turkey has been the unique target of international terrorism since 1965. Taking into consideration her geographical location, social...

T. Olcay

1991-01-01

159

Angiotensin II inhibits satellite cell proliferation and prevents skeletal muscle regeneration.  

PubMed

Cachexia is a serious complication of many chronic diseases, such as congestive heart failure (CHF) and chronic kidney disease (CKD). Although patients with advanced CHF or CKD often have increased angiotensin II (Ang II) levels and cachexia and Ang II causes skeletal muscle wasting in rodents, the potential effects of Ang II on muscle regeneration are unknown. Muscle regeneration is highly dependent on the ability of a pool of muscle stem cells (satellite cells) to proliferate and to repair damaged myofibers or form new myofibers. Here we show that Ang II reduced skeletal muscle regeneration via inhibition of satellite cell (SC) proliferation. Ang II reduced the number of regenerating myofibers and decreased expression of SC proliferation/differentiation markers (MyoD, myogenin, and active-Notch) after cardiotoxin-induced muscle injury in vivo and in SCs cultured in vitro. Ang II depleted the basal pool of SCs, as detected in Myf5(nLacZ/+) mice and by FACS sorting, and this effect was inhibited by Ang II AT1 receptor (AT1R) blockade and in AT1aR-null mice. AT1R was highly expressed in SCs, and Notch activation abrogated the AT1R-mediated antiproliferative effect of Ang II in cultured SCs. In mice that developed CHF postmyocardial infarction, there was skeletal muscle wasting and reduced SC numbers that were inhibited by AT1R blockade. Ang II inhibition of skeletal muscle regeneration via AT1 receptor-dependent suppression of SC Notch and MyoD signaling and proliferation is likely to play an important role in mechanisms leading to cachexia in chronic disease states such as CHF and CKD. PMID:23831688

Yoshida, Tadashi; Galvez, Sarah; Tiwari, Sumit; Rezk, Bashir M; Semprun-Prieto, Laura; Higashi, Yusuke; Sukhanov, Sergiy; Yablonka-Reuveni, Zipora; Delafontaine, Patrice

2013-07-06

160

Establishment and characterization of human embryonic stem cell lines, Turkey perspectives  

Microsoft Academic Search

Human embryonic stem cells (hESC), which are derived from the inner cell mass (ICM) of blastocyst stage embryos, are of great\\u000a importance because of their unpredictable two unique features: their differentiation ability into all types of cells derived\\u000a from three germ layers and their potentially unlimited capacity of self renewing with stable karyotype. These distinguished\\u000a properties make hESC very promising

Zafer Nihat Candan; Semra Kahraman

2010-01-01

161

Diversity of killer cell immunoglobulin-like receptor genes in Southern Turkey  

Microsoft Academic Search

Killer cell immunoglobulin-like receptors (KIRs) are a family of inhibitory and activating receptors expressed by natural\\u000a killer (NK) cells and regulate NK cells’ activity. KIR genes are highly polymorphic markers, characterized by a wide diversity,\\u000a and can therefore be considered as good population genetic markers. The aim of this study was to determine KIR gene frequencies,\\u000a ratios of haplotypes and

Ozlem Goruroglu Ozturk; Gurbuz Polat; Ugur Atik

162

The function of death-associated protein 1 in proliferation, differentiation, and apoptosis of chicken satellite cells.  

PubMed

Introduction: Muscle growth and regeneration are processes closely associated with the proliferation, differentiation, and apoptosis of muscle cells. Death-associated protein 1 (DAP1) has been identified as a negative regulator of autophagy. Little is known about the function of DAP1 in the regulation of myogenesis and satellite cells. Methods: Chicken satellite cells were transfected with DAP1 cloned into the pCMS-Enhanced Green Fluorescent Protein vector or pcDNA3.1 vector, or a small interference RNA against the endogenous DAP1 gene. They were assayed for proliferation, differentiation, and apoptosis. Results: The over-expression of DAP1 increased proliferation, differentiation, and myotube diameter but it had no effect on satellite cell apoptosis. In contrast, knockdown of DAP1 significantly decreased proliferation, differentiation, and number of nuclei per myotube, and it increased apoptosis of the cells. Conclusion: DAP1 is required for regulating myogenesis and apoptosis of satellite cells, which may affect muscle mass accretion and regeneration, and ameliorate muscle sarcopenia. © 2013 Wiley Periodicals, Inc. PMID:23483580

Shin, Jonghyun; McFarland, Douglas C; Strasburg, Gale M; Velleman, Sandra G

2013-03-01

163

Turkey's Constitutional Zigzags  

Microsoft Academic Search

Turkey is unique among contemporary Muslim societies. Modern Turkey emerged as a nation-state after the collapse of the Ottoman Empire and the abolition of the Caliphate in 1924 and has been a republic since 1923. Discarding the theological trappings of the Ottoman state, where the sultan was also the caliph, Turkey opted for the privatization of the Muslim faith, along

Seyla Benhabib

2009-01-01

164

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

PubMed Central

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.

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

1994-01-01

165

DNA methylation analysis on satellite I region in blastocysts obtained from somatic cell cloned cattle.  

PubMed

Many observations have been made on cloned embryos and on adult clones by somatic cell nuclear transfer (SCNT), but it is still unclear whether the progeny of cloned animals is presenting normal epigenetic status. Here, in order to accumulate the information for evaluating the normality of cloned cattle, we analyzed the DNA methylation status on satellite I region in blastocysts obtained from cloned cattle. Embryos were produced by artificial insemination (AI) to non-cloned or cloned dams using semen from non-cloned or cloned sires. After 7 days of AI, embryos at blastocyst stage were collected by uterine flushing. The DNA methylation levels in embryos obtained by using semen and/or oocytes from cloned cattle were similar to those in in vivo embryos from non-cloned cattle. In contrast, the DNA methylation levels in SCNT embryos were significantly higher (P < 0.01) than those in in vivo embryos from non-cloned and cloned cattle, approximately similar to those in somatic cells used as donor cells. Thus, this study provides useful information that epigenetic status may be normal in the progeny of cloned cattle, suggesting the normality of germline cells in cloned cattle. PMID:21794009

Yamanaka, Ken-Ichi; Kaneda, Masahiro; Inaba, Yasushi; Saito, Koji; Kubota, Kaiyu; Sakatani, Miki; Sugimura, Satoshi; Imai, Kei; Watanabe, Shinya; Takahashi, Masashi

2011-04-20

166

Mutations in the satellite cell gene MEGF10 cause a recessive congenital myopathy with minicores.  

PubMed

We ascertained a nuclear family in which three of four siblings were affected with an unclassified autosomal recessive myopathy characterized by severe weakness, respiratory impairment, scoliosis, joint contractures, and an unusual combination of dystrophic and myopathic features on muscle biopsy. Whole genome sequence from one affected subject was filtered using linkage data and variant databases. A single gene, MEGF10, contained nonsynonymous mutations that co-segregated with the phenotype. Affected subjects were compound heterozygous for missense mutations c.976T?>?C (p.C326R) and c.2320T?>?C (p.C774R). Screening the MEGF10 open reading frame in 190 patients with genetically unexplained myopathies revealed a heterozygous mutation, c.211C?>?T (p.R71W), in one additional subject with a similar clinical and histological presentation as the discovery family. All three mutations were absent from at least 645 genotyped unaffected control subjects. MEGF10 contains 17 atypical epidermal growth factor-like domains, each of which contains eight cysteine residues that likely form disulfide bonds. Both the p.C326R and p.C774R mutations alter one of these residues, which are completely conserved in vertebrates. Previous work showed that murine Megf10 is required for preserving the undifferentiated, proliferative potential of satellite cells, myogenic precursors that regenerate skeletal muscle in response to injury or disease. Here, knockdown of megf10 in zebrafish by four different morpholinos resulted in abnormal phenotypes including unhatched eggs, curved tails, impaired motility, and disorganized muscle tissue, corroborating the pathogenicity of the human mutations. Our data establish the importance of MEGF10 in human skeletal muscle and suggest satellite cell dysfunction as a novel myopathic mechanism. PMID:22371254

Boyden, Steven E; Mahoney, Lane J; Kawahara, Genri; Myers, Jennifer A; Mitsuhashi, Satomi; Estrella, Elicia A; Duncan, Anna R; Dey, Friederike; DeChene, Elizabeth T; Blasko-Goehringer, Jessica M; Bönnemann, Carsten G; Darras, Basil T; Mendell, Jerry R; Lidov, Hart G W; Nishino, Ichizo; Beggs, Alan H; Kunkel, Louis M; Kang, Peter B

2012-02-28

167

Sphingolipidoses in Turkey.  

PubMed

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

Ozkara, Hatice Asuman; Topçu, Meral

2004-09-01

168

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

PubMed

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

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

2013-08-28

169

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

PubMed Central

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.

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

2013-01-01

170

Establishment and characterization of human embryonic stem cell lines, Turkey perspectives.  

PubMed

Human embryonic stem cells (hESC), which are derived from the inner cell mass (ICM) of blastocyst stage embryos, are of great importance because of their unpredictable two unique features: their differentiation ability into all types of cells derived from three germ layers and their potentially unlimited capacity of self renewing with stable karyotype. These distinguished properties make hESC very promising cell source for regenerative medicine, tissue replacement therapies, and drug screening studies as well as genomics. However, due to the several technical problems, such as risk of teratoma formation, immune response, and unknown genetic pathways for lineage specific differentiation, and ethical drawbacks of their using in clinical treatments, hESC researches are still waiting to advance beyond to animal trials and drug studies. During the last decade, more than 300 new hESC lines have been derived and published by researchers worldwide. However, despite their similar well-known unique properties, recent studies reported that hESC lines have very individual properties and are differed from each other with regards to their differentiation ability and gene expression profiles. Therefore, all hESC lines should be characterized in detail and then registered in a stem cell bank for generating global database. In this report, the characteristic of hESC lines, which were established in Istanbul Memorial Hospital between 2003 and 2005, and derivation methods were described in detail to inform researchers and to facilitate new prospective cooperative studies. PMID:20349214

Candan, Zafer Nihat; Kahraman, Semra

2010-03-27

171

Alterations of the Immunological Specificity of Plasma Membranes from Cells Infected with Marek's Disease and Turkey Herpes Viruses  

Microsoft Academic Search

SUMMARY Highly purified plasma membranes were isolated from chicken embryo fibro- blasts infected with Marek's disease virus (MDV) or turkey herpes virus (HVT). The purification was monitored by the incorporation of fucose and marker en- zymes specific for plasma membranes. Polyacrylamide gel electrophoresis showed that the membrane preparations contained two new virus-induced proteins. When reacted in the double immunodiffusion test

O. R. Kaaden; B. Dietzschold

1974-01-01

172

c-Flip overexpression affects satellite cell proliferation and promotes skeletal muscle aging.  

PubMed

This study shows that forcing c-Flip overexpression in undifferentiated skeletal myogenic cells in vivo results in early aging muscle phenotype. In the transgenic mice, adult muscle histology, histochemistry and biochemistry show strong alterations: reduction of fibers size and muscle mass, mitochondrial abnormalities, increase in protein oxidation and apoptosis markers and reduced AKT/GSK3? phosphorylation. In the infant, higher levels of Pax-7, PCNA, P-ERK and active-caspase-3 were observed, indicating enhanced proliferation and concomitant apoptosis of myogenic precursors. Increased proliferation correlated with NF-?B activation, detected as p65 phosphorylation, and with high levels of embryonic myosin heavy chain. Reduced regenerative potential after muscle damage in the adult and impaired fiber growth associated with reduced NFATc2 activation in the infant were also observed, indicating that the satellite cell pool is prematurely compromised. Altogether, these data show a role for c-Flip in modulating skeletal muscle phenotype by affecting the proliferative potential of undifferentiated cells. This finding indicates a novel additional mechanism through which c-Flip might possibly control tissue remodeling. PMID:21364645

Giampietri, C; Petrungaro, S; Coluccia, P; Antonangeli, F; Giannakakis, K; Faraggiana, T; Filippini, A; Cossu, G; Ziparo, E

2010-04-29

173

Numerical densities of myonuclei and satellite cells in muscle fiber types in the aging human thyroarytenoid muscle: An immunohistochemical and stereological study using confocal laser scanning microscopy  

Microsoft Academic Search

Objective: This study determines the role of changes in numerical densities of myonuclei and satellite cells in age-related remodeling of the thyroarytenoid muscle (TA). Design: Changes in numerical densities (NN) and ratios (NV) of myonuclei and satellite cells were estimated for the entire TA by use of stereological techniques. Results: There was no age-related change or difference between fiber types

Leslie T. Malmgren; Patricia J. Fisher; Christine E. Jones; Linda M. Bookman; Toshiyuki Uno

2000-01-01

174

Human Metapneumovirus in Turkey Poults  

PubMed Central

This study was conducted to reexamine the hypothesis that human metapneumovirus (hMPV) will not infect turkeys. Six groups of 2-week-old turkeys (20 per group) were inoculated oculonasally with 1 of the following: noninfected cell suspension; hMPV genotype A1, A2, B1, or B2; or avian metapneumovirus (aMPV) subtype C. Poults inoculated with hMPV showed nasal discharge days 4–9 postexposure. Specific viral RNA and antigen were detected by reverse-transcription PCR and immunohistochemical evaluation, respectively, in nasal turbinates of birds exposed to hMPV. Nasal turbinates of hMPV-infected turkeys showed inflammatory changes and mucus accumulation. Each of the 4 hMPV genotypes caused a transient infection in turkeys as evidenced by clinical signs, detection of hMPV in turbinates, and histopathologic examination. Detailed investigation of cross-species pathogenicity of hMPV and aMPV and its importance for human and animal health is needed.

Velayudhan, Binu T.; Nagaraja, Kakambi V.; Thachil, Anil J.; Shaw, Daniel P.; Gray, Gregory C.

2006-01-01

175

Transient systemic mtDNA damage leads to muscle wasting by reducing the satellite cell pool.  

PubMed

With age, muscle mass and integrity are progressively lost leaving the elderly frail, weak and unable to independently care for themselves. Defined as sarcopenia, this age-related muscle atrophy appears to be multifactorial but its definite cause is still unknown. Mitochondrial dysfunction has been implicated in this process. Using a novel transgenic mouse model of mitochondrial DNA (mtDNA) double-strand breaks (DSBs) that presents a premature aging-like phenotype, we studied the role of mtDNA damage in muscle wasting. We caused DSBs in mtDNA of adult mice using a ubiquitously expressed mitochondrial-targeted endonuclease, mito-PstI. We found that a short, transient systemic mtDNA damage led to muscle wasting and a decline in locomotor activity later in life. We found a significant decline in muscle satellite cells, which decreases the muscle's capacity to regenerate and repair during aging. This phenotype was associated with impairment in acetylcholinesterase (AChE) activity and assembly at the neuromuscular junction (NMJ), also associated with muscle aging. Our data suggests that systemic mitochondrial dysfunction plays important roles in age-related muscle wasting by preferentially affecting the myosatellite cell pool. PMID:23760083

Wang, Xiao; Pickrell, Alicia M; Rossi, Susana G; Pinto, Milena; Dillon, Lloye M; Hida, Aline; Rotundo, Richard L; Moraes, Carlos T

2013-06-10

176

Genetic loci controlling lethal cell death in tomato caused by viral satellite RNA infection.  

PubMed

Cucumber mosaic virus (CMV) associated with D satellite RNA (satRNA) causes lethal systemic necrosis (LSN) in tomato (Solanum lycopersicum), which involves programmed cell death. No resistance to this disease has been found in tomato. We obtained a line of wild tomato, S. habrochaitis, with a homogeneous non-lethal response (NLR) to the infection. This line of S. habrochaitis was crossed with tomato to generate F1 plants that survived the infection with NLR, indicating that NLR is a dominant trait. The NLR trait was successfully passed on to the next generation. The phenotype and genotype segregation was analyzed in the first backcross population. The analyses indicate that the NLR trait is determined by quantitative trait loci (QTL). Major QTL associated with the NLR trait were mapped to chromosomes 5 and 12. Results from Northern blot and in situ hybridization analyses revealed that the F1 and S. habrochaitis plants accumulated minus-strand satRNA more slowly than tomato, and fewer vascular cells were infected. In addition, D satRNA-induced LSN in tomato is correlated with higher accumulation of the minus-strand satRNA compared with the accumulation of the minus strand of a non-necrogenic mutant D satRNA. PMID:22746824

Xu, Ping; Wang, Hua; Coker, Frank; Ma, Jun-Ying; Tang, Yuhong; Taylor, Mark; Roossinck, Marilyn J

2012-08-01

177

Satellite glial cells in the trigeminal ganglion as a determinant of orofacial neuropathic pain  

PubMed Central

Satellite glial cells (SGCs) tightly envelop the perikarya of primary sensory neurons in peripheral ganglion and are identified by their morphology and the presence of proteins not found in ganglion neurons. These SGC-unique proteins include the inwardly rectifying K+ channel Kir4.1, the connexin-43 (Cx43) subunit of gap junctions, the purinergic receptor P2Y4 and soluble guanylate cyclase. We also present evidence that the small-conductance Ca2+-activated K+ channel SK3 is present only in SGCs and that SGCs divide following nerve injury. All the above proteins are involved, either directly or indirectly, in potassium ion (K+) buffering and, thus, can influence the level of neuronal excitability, which, in turn, has been associated with neuropathic pain conditions. We used in vivo RNA interference to reduce the expression of Cx43 (present only in SGCs) in the rat trigeminal ganglion and show that this results in the development of spontaneous pain behavior. The pain behavior is present only when Cx43 is reduced and returns to normal when Cx43 concentrations are restored. This finding shows that perturbation of a single SGC-specific protein is sufficient to induce pain responses and demonstrates the importance of PNS glial cell activity in the pathophysiology of neuropathic pain.

VIT, JEAN-PHILIPPE; JASMIN, LUC; BHARGAVA, ADITI; OHARA, PETER T.

2008-01-01

178

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

PubMed

Here, for the first time, we evaluate the hypothesis that the proliferative abilities of satellite cells (SCs) isolated from Lantang (indigenous Chinese pigs) and Landrace pigs, which differ in muscle characteristics, are different. SCs were isolated from the longissimus dorsi muscle of neonatal Lantang and Landrace pigs. Proliferative ability was estimated by the count and proliferative activity of viable cells using a hemocytometer and MTT assay at different time points after seeding, respectively. Cell cycle information was detected by flow cytometry. Results showed that there was a greater (P<0.05) number of SCs in Lantang pigs compared with Landrace pigs after 72 h of culture. The percentage of cell population in S phase and G(2)/M phases in Lantang pigs were higher (P<0.05), while in G(0)/G(1) phase was lower (P<0.05) in comparison with the Landrace pigs. The mRNA abundances of MyoD, Myf5, myogenin and Pax7 in SCs from Lantang pigs were higher (P<0.05), while those of myostatin, Smad3 and genes in the mammalian target of rapamycin (mTOR) pathway (with the exception of 4EBP1) were lower (P<0.05) than the Landrace pigs. Protein levels of MyoD, myogenin, myostatin, S6K, phosphorylated mTOR and phosphorylated eIF4E were consistent with the corresponding mRNA abundance. Collectively, these findings suggested that SCs in the two breeds present different proliferative abilities, and the proliferative potential of SCs in Lantang pigs is higher than in Landrace pigs. PMID:22427853

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

2012-03-13

179

Human muscle satellite cells show age-related differential expression of S100B protein and RAGE  

Microsoft Academic Search

During aging, skeletal muscles show reduced mass and functional capacity largely due to loss of the regenerative ability of\\u000a satellite cells (SCs), the quiescent stem cells located beneath the basal lamina surrounding each myofiber. While both the\\u000a external environment and intrinsic properties of SCs appear to contribute to the age-related SC deficiency, the latter ones\\u000a have been poorly investigated especially

Sara Beccafico; Francesca Riuzzi; Cristina Puglielli; Rosa Mancinelli; Stefania Fulle; Guglielmo Sorci; Rosario Donato

180

Transcription factor YY1 associates with pericentromeric ?-satellite DNA in cycling but not in quiescent (G0) cells  

PubMed Central

Pericentromeric ?-satellite DNA is organized in constitutive heterochromatin structures. It comprises a 234 bp sequence repeated several thousands times surrounding the centromeric sequence of all murine chromosomes. Potential binding sites for transcription factor Yin Yang 1 (YY1), a repressor or activator of several cellular and viral genes, are present in pericentromeric ?-satellite DNA. Using gel retardation and chromatin immunoprecipitation, we demonstrate in this work that YY1 specifically interacts in vitro and in vivo with ?-satellite DNA. Using immunoFISH and confocal microscopy we show that YY1 specifically co-localizes with pericentromeric ?-satellite DNA clusters organized in constitutive heterochromatin in murine L929 and 3T3 fibroblasts cell lines. Immunoelectron microscopy experiments further confirmed YY1 localization in heterochromatic areas. Overall, our results demonstrate for the first time that a fraction of YY1 is directly associated with constitutive heterochromatin structures. This association appears physiologically relevant since the association of YY1 with pericentromeric ?-satellite DNA observed in cycling 3T3 fibroblasts strongly diminished in quiescent (G0) 3T3 fibroblasts. We discuss the implications of these results in the context of heterochromatin formation as well as with regard to the YY1-induced repression of euchromatic genes.

Shestakova, Elena A.; Mansuroglu, Zeyni; Mokrani, Houda; Ghinea, Nicolae; Bonnefoy, Eliette

2004-01-01

181

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

NASA Astrophysics Data System (ADS)

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.

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

2011-07-01

182

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

PubMed Central

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

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

2011-01-01

183

Activation of Satellite Glial Cells in Rat Trigeminal Ganglion after Upper Molar Extraction  

PubMed Central

The neurons in the trigeminal ganglion (TG) are surrounded by satellite glial cells (SGCs), which passively support the function of the neurons, but little is known about the interactions between SGCs and TG neurons after peripheral nerve injury. To examine the effect of nerve injury on SGCs, we investigated the activation of SGCs after neuronal damage due to the extraction of the upper molars in rats. Three, 7, and 10 days after extraction, animals were fixed and the TG was removed. Cryosections of the ganglia were immunostained with antibodies against glial fibrillary acidic protein (GFAP), a marker of activated SGCs, and ATF3, a marker of damaged neurons. After tooth extraction, the number of ATF3-immunoreactive (IR) neurons enclosed by GFAP-IR SGCs had increased in a time-dependent manner in the maxillary nerve region of the TG. Although ATF3-IR neurons were not detected in the mandibular nerve region, the number of GFAP-IR SGCs increased in both the maxillary and mandibular nerve regions. Our results suggest that peripheral nerve injury affects the activation of TG neurons and the SGCs around the injured neurons. Moreover, our data suggest the existence of a neuronal interaction between maxillary and mandibular neurons via SGC activation.

Gunjigake, Kaori K.; Goto, Tetsuya; Nakao, Kayoko; Kobayashi, Shigeru; Yamaguchi, Kazunori

2009-01-01

184

Satellite glia cells in dorsal root ganglia express functional NMDA receptors.  

PubMed

Satellite glia cells (SGCs), within the dorsal root ganglia (DRG), surround the somata of most sensory neurons. SGCs have been shown to interact with sensory neurons and appear to be involved in the processing of afferent information. We found that in rat DRG various N-methyl-D-aspartate receptor (NMDAr) subunits were expressed in SGCs in intact ganglia and in vitro. In culture, when SGCs were exposed to brief pulses of NMDA they evoked transient increases in cytoplasmic calcium that were inhibited by specific NMDA blockers (MK-801, AP5) while they were Mg²? insensitive indicating that SGCs express functional NMDAr. The percentage of NMDA responsive SGCs was similar in mixed- (SGCs plus neurons) and SGC-enriched cultures. The pattern of the magnitude changes of the NMDA-evoked response was similar in SGCs and DRG neurons when they were in close proximity, suggesting that the NMDA response of SGCs and DRG neurons is modulated by their interactions. Treating the cultures with nerve growth factor, and/or prostaglandin E? did not alter the percentage of SGCs that responded to NMDA. Since glutamate appears to be released within the DRG, the detection of functional NMDAr in SGCs suggests that their NMDAr activity could contribute to the interactions between neurons and SGCs. In summary we demonstrated for the first time that SGCs express functional NMDAr. PMID:23485802

Castillo, C; Norcini, M; Martin Hernandez, L A; Correa, G; Blanck, T J J; Recio-Pinto, E

2013-02-26

185

Somatostatin modulates mast cell-induced responses in murine spinal neurons and satellite cells  

PubMed Central

The course of intestinal inflammatory responses is tightly coordinated by the extensive communication between the immune system and the enteric nervous system, among which the bidirectional mast cell-neuron interaction within the intestinal wall plays a prominent role. Recent research suggests that somatostatin (SOM) is able to inhibit this self-reinforcing network by simultaneously suppressing the inflammatory activities of both neurons and mast cells. Therefore, we assessed the modulatory effects of SOM on both the short-term and long-term effects induced by the main mast cell mediators histamine (HIS) and 5-HT on spinal sensory neurons. Short-term incubation of dorsal root ganglion cultures with HIS and 5-HT induced neuronal CGRP-release and calcium-mediated activation of both neurons and nonneuronal cells, both of which effects were significantly reduced by SOM. In addition, SOM was also able to suppress the increased neuronal expression of pro- and anti-inflammatory peptides induced by long-term exposure to HIS and 5-HT. Immunocytochemical and molecular-biological experiments revealed the possible involvement of somatostatin receptor 1 (SSTR1) and SSTR2A in these profound SOM-dependent effects. These data, combined with the increased expression of pro- and anti-inflammatory peptides and several SSTRs in murine dorsal root ganglia following intestinal inflammation, reveal that intestinal inflammation not only induces the onset of proinflammatory cascades but simultaneously triggers endogenous systems destined to prevent excessive tissue damage. Moreover, these data provide for the first time functional evidence that SOM is able to directly modulate intestinal inflammatory responses by interference with the coordinating mast cell-neuron communication.

Van Op den bosch, Joeri; Van Nassauw, Luc; Van Marck, Eric; Timmermans, Jean-Pierre

2009-01-01

186

MicroRNA-133 controls brown adipose determination in skeletal muscle satellite cells by targeting Prdm16.  

PubMed

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

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

2013-02-01

187

Myocarditis associated with reovirus in turkey poults.  

PubMed

Myocarditis associated with reovirus was diagnosed in 17-day-old, male turkey poults, based on virus isolation, reverse transcriptase-polymerase chain reaction (RT-PCR), demonstration of reovirus antigen in the cytoplasm of mononuclear inflammatory cells and myocytes in the heart by immunohistochemistry (IHC), and reovirus particles in the endoplasmic reticulum of myocytes by transmission electron microscopy (TEM). Clinical signs in the poults included anorexia, growth depression, and increased mortality. Gross lesions in the six poults examined were increased pericardial fluid, mild-to-moderate dilation of right ventricles, pale-yellow myocardium, and ascites. Other lesions in a few birds included mild pulmonary edema, congestion, and pale serosa of the small intestine that had watery contents in their lumens. Microscopically, in the heart, there was mild-to-severe necrosis of myocytes and infiltration of primarily lymphocytes mixed with a few heterophils, macrophages, and occasionally, plasma cells and multinucleated giant cells. There was mild-to-moderate lymphoid depletion in the bursa of Fabricius. Reovirus was isolated from the heart of the turkey poults in chicken-embryo liver cells and was confirmed by RT-PCR, IHC, and TEM. A retrospective search of the laboratory database for cases of myocarditis associated with reovirus in turkeys revealed that this condition has occurred sporadically in California turkey flocks since 1991. This is the first documentation of myocarditis in turkey poults associated with reovirus. PMID:20095152

Shivaprasad, H L; Franca, M; Woolcock, P R; Nordhausen, R; Day, J M; Pantin-Jackwood, M

2009-12-01

188

Electrode structure analysis and surface characterization for lithium-ion cells simulated low-Earth-orbit satellite operation  

Microsoft Academic Search

As a sequence work to investigate the performance-degradation mechanism of an aged commercial laminated lithium-ion cell experiencing 4350-cycle charge–discharge in a simulated low-Earth-orbit (LEO) satellite operation, we performed the surface characterization of LiCoO2 cathode and graphite anode by Fourier transform infrared-Attenuated total reflection (FTIR-ATR) and X-ray photoelectron spectroscopy (XPS) analysis in this work. Overall, the graphite anode had a larger

Xianming Wang; Toshiya Hironaka; Eiji Hayashi; Chisa Yamada; Hitoshi Naito; Go Segami; Yoko Sakiyama; Yoshikazu Takahashi; Koichi Kibe

2007-01-01

189

Dynamic Elastic Behavior of oL-Satellite DNA Domains Visualized In Situ in Living Human Cells  

Microsoft Academic Search

We have constructed a fluorescent a-satellite DNA-binding protein to explore the motile and me- chanical properties of human centromeres. A fusion protein consisting of human CENP-B coupled to the green fluorescent protein (GFP) of A. victoria specifi- cally targets to centromeres when expressed in human cells. Morphometric analysis revealed that the a-satel- lite DNA domain bound by CENPB-GFP becomes elongated

Richard D. Shelby; Klaus M. Hahn; Kevin F. Sullivan

1996-01-01

190

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

PubMed

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

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

2012-04-16

191

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

PubMed Central

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.

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

2012-01-01

192

Contribution to the mechanisms of compressing Prandtl Cell Model: The Karliova Triple Junction as a case study from Eastern Turkey  

NASA Astrophysics Data System (ADS)

The Prandtl Cell (PC) model consists of an ideally plastic material, which is compressed between two parallel rigid plates (Prandtl, 1924). In the original PC model the material is allowed to flow only in one direction in response to compressive stresses. The original PC setting has been modified to accommodate different boundary conditions in later studies. For example, the plastic material is allowed to flow either towards or away from the apex of the wedge, where non-parallel plates move towards or away from each other. Cummings (1976) set up four different boundary conditions and classified four different PC models according to the geometry of the slip lines, the relative movement along the slip lines, and the movement of the plastic material. But none of the models explain the exact features of the slip lines and which factors controlled them. In this study, we consider one of the models of Cummings (1976) and we use field data, morphotectonic indices and analogue model results to interpret the fault pattern near the Karliova Triple Junction in Eastern Turkey, where the North Anatolian Fault Zone (NAFZ) and the East Anatolian Fault Zone EAFZ) meet. Quantified geomorphic features are used to understand local tectonic signals. We analyzed the drainage patterns, long profiles and hypsometric integral of bedrock rivers that drain across and around secondary faults between the NAFZ and the EAFZ. Morphotectonic analysis of different river system, which are bounded by strike-slip faults show that not only morphotectonic features but also deformation styles vary along the slip lines. Analyzing fourty branches of two main river systems between the NAFZ and EAFZ reveal that secondary faults can be classified into two fault sets. The first and most prominent fault,that formed close to NAFZ, consists of strike-slip faults that change along strike into oblique normal-slip faults when the strike of the fault changes from from NW to SE: The second fault set is less clearly recognizable and has a sinistral sense of slip. The constructed analogy of long profile and hypsometric integral demonstrates that those faults which formed near the EAFZ are tectonically quiescent whereas those that formed close to NAFZ are tectonically active. Our analysis shows that rivers controlled by these latter faults are undergoing permanent response to continuous tectonic uplift. Furthermore, the change of motion from dominant strike-slip to normal faulting creates the classic stratigraphic landform-cuesta-. Orientation of the NAFZ, the EAFZ and secondary faults between them are very similar to the PC model of Cummings (1976; Fig. 2B). Combining analogue models and morphotectonic analysis suggest that secondary faults propagated from west to east. The compressive stress distribution in analogue models varies along the boundary plates and the open ends of NAFZ and EAFZ triangle. From west to east formation of faults is both confirmed by morphotectonic analysis and analogue model experiment. In summary, for the region between the most eastern NAFZ, and the most northern EAFZ, we show that the compressive PC model slip lines start to develop from west to east. The sense of motion, the magnitude of displacement, and the evolving landcapes along these slip lines are fully controlled by the velocities of the boundary faults.

Sançar, Taylan; Schreurs, Guido; Zabc?, Cengiz; Akyüz, H. Serdar

2013-04-01

193

Distance Education in Turkey  

ERIC Educational Resources Information Center

|Many countries of the world are using distance education with various ways, by INTERNET, by post and by TV. In this work, development of distance education in Turkey has been presented from the beginning. After discussing types and applications for different levels of distance education in Turkey, the distance education was given in the cultural…

Ruzgar, Nursel Selver

2004-01-01

194

OSTEOMYELITIS IN COMMERCIAL TURKEYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Turkey osteomyelitis complex (TOC) is a disease syndrome characterized by the presence of green liver, synovitis, osteomyelitis of the proximal tibia, and soft tissue abscesses in the carcasses of processed turkeys. We have established that these lesions are caused by opportunistic bacterial infecti...

195

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

PubMed

Exercise-induced muscle damage is an important topic in exercise physiology. However several aspects of our understanding of how muscles respond to highly stressful exercise remain unclear In the first section of this review we address the evidence that exercise can cause muscle damage and inflammation in otherwise healthy human skeletal muscles. We approach this concept by comparing changes in muscle function (i.e., the force-generating capacity) with the degree of leucocyte accumulation in muscle following exercise. In the second section, we explore the cytokine response to 'muscle-damaging exercise', primarily eccentric exercise. We review the evidence for the notion that the degree of muscle damage is related to the magnitude of the cytokine response. In the third and final section, we look at the satellite cell response to a single bout of eccentric exercise, as well as the role of the cyclooxygenase enzymes (COX1 and 2). In summary, we propose that muscle damage as evaluated by changes in muscle function is related to leucocyte accumulation in the exercised muscles. 'Extreme' exercise protocols, encompassing unaccustomed maximal eccentric exercise across a large range of motion, generally inflict severe muscle damage, inflammation and prolonged recovery (> 1 week). By contrast, exercise resembling regular athletic training (resistance exercise and downhill running) typically causes mild muscle damage (myofibrillar disruptions) and full recovery normally occurs within a few days. Large variation in individual responses to a given exercise should, however be expected. The link between cytokine and satellite cell responses and exercise-induced muscle damage is not so clear The systemic cytokine response may be linked more closely to the metabolic demands of exercise rather than muscle damage. With the exception of IL-6, the sources of systemic cytokines following exercise remain unclear The satellite cell response to severe muscle damage is related to regeneration, whereas the biological significance of satellite cell proliferation after mild damage or non-damaging exercise remains uncertain. The COX enzymes regulate satellite cell activity, as demonstrated in animal models; however the roles of the COX enzymes in human skeletal muscle need further investigation. We suggest using the term 'muscle damage' with care. Comparisons between studies and individuals must consider changes in and recovery of muscle force-generating capacity. PMID:22876722

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

2012-01-01

196

NOAA's Satellites  

NSDL National Science Digital Library

The National Oceanic & Atmospheric Administration (NOAA) maintains this centralized resource on NOAA satellites, of interest to life and physical scientists alike. Featured and described here are NOAA's National Environmental Satellite, Data and Information Service (NESDIS); NOAA's CoastWatch Program; and hundreds of Archived Satellite Images, Storm Animations and Special Events. Each section of the site points users to wealth of further information, spanning the technology of satellites to real-time satellite images. For users ranging from the curious student to the driven researcher, this site plays a central role in organizing NOAA satellite information.

197

Satellite reconnaissance  

NASA Astrophysics Data System (ADS)

The potential of the observation equipment in remote sensing satellites is described. United States meteorology, land use and oceanography satellites and the major US Earth observation programs are listed. Imaging satellite systems are described such as: visible light and near infrared, thermal IR window, and microwave window. It is concluded that a geometrical resolution between 10 and 40 m can be expected. In order to reduce the data flow from the satellite system the input side of the system (the object-sensor interaction) has to be known. Satellites with synthetic aperture radar are increasingly important, but satellites can never fully replace observations with aircraft and drones.

Deloor, G. P.

1984-06-01

198

The effects of clenbuterol on satellite cell activation and the regeneration of skeletal muscle: an autoradiographic and morphometric study of whole muscle transplants in mice.  

PubMed

The beta-2 agonist clenbuterol was tested for its effect on the proliferation of satellite cells in transplanted skeletal muscles. Using autoradiographic techniques it was found that satellite cells in clenbuterol treated transplants began proliferating earlier than in control animals. The effect of clenbuterol on the growth of regenerating muscle fibres was also examined using morphometric techniques, which manifested itself as hypertrophy of the fibres when compared with the controls. PMID:1452482

Roberts, P; McGeachie, J K

1992-02-01

199

Hypoxia Increases Mouse Satellite Cell Clone Proliferation Maintaining both In Vitro and In Vivo Heterogeneity and Myogenic Potential  

PubMed Central

Satellite cells (SCs) are essential for postnatal muscle growth and regeneration, however, their expansion potential in vitro is limited. Recently, hypoxia has been used to enhance proliferative abilities in vitro of various primary cultures. Here, by isolating SCs from single mouse hindlimb skeletal myofibers, we were able to distinguish two subpopulations of clonally cultured SCs (Low Proliferative Clones - LPC - and High Proliferative Clones - HPC), which, as shown in rat skeletal muscle, were present at a fixed proportion. In addition, culturing LPC and HPC at a low level of oxygen we observed a two fold increased proliferation both for LPC and HPC. LPC showed higher myogenic regulatory factor (MRF) expression than HPC, particularly under the hypoxic condition. Notably, a different myogenic potential between LPC and HPC was retained in vivo: green fluorescent protein (GFP)+LPC transplantation in cardiotoxin-injured Tibialis Anterior led to a higher number of new GFP+muscle fibers per transplanted cell than GFP+HPC. Interestingly, the in vivo myogenic potential of a single cell from an LPC is similar if cultured both in normoxia and hypoxia. Therefore, starting from a single satellite cell, hypoxia allows a larger expansion of LPC than normal O2 conditions, obtaining a consistent amount of cells for transplantation, but maintaining their myogenic regeneration potential.

Urbani, Luca; Piccoli, Martina; Franzin, Chiara

2012-01-01

200

Syndecan-3 and Syndecan-4 Specifically Mark Skeletal Muscle Satellite Cells and Are Implicated in Satellite Cell Maintenance and Muscle Regeneration  

Microsoft Academic Search

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

D. D. W. Cornelison; Mark S. Filla; Heather M. Stanley; Alan C. Rapraeger; Bradley B. Olwin

2001-01-01

201

Tadpole Satellite.  

National Technical Information Service (NTIS)

A low cost synchronous orbit satellite to evaluate small mercury bombardment ion thruster applications is described. The ion thrusters provide the satellite with precise north-south and east-west stationkeeping capabilities. In addition, the thrusters are...

1974-01-01

202

Meteorological Satellites.  

National Technical Information Service (NTIS)

An overview is presented of the meteorological satellite programs that have been evolving from 1958 to the present, and plans for the future meteorological and environmental satellite systems that are scheduled to be placed into service in the early 1980'...

A. Schnapf A. Schwalb B. C. Diesen L. J. Allison P. S. Martin

1980-01-01

203

Decreasing trend of groundwater in Turkey  

NASA Astrophysics Data System (ADS)

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

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

2010-12-01

204

Satellite reconnaissance  

Microsoft Academic Search

The potential of the observation equipment in remote sensing satellites is described. United States meteorology, land use and oceanography satellites and the major US Earth observation programs are listed. Imaging satellite systems are described such as: visible light and near infrared, thermal IR window, and microwave window. It is concluded that a geometrical resolution between 10 and 40 m can

G. P. Deloor

1984-01-01

205

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)

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.

Reid, Margaret A.

1991-11-01

206

Hydropower potential in Turkey  

SciTech Connect

Turkey has a total hydropower potential of 433 GW that is equal to 1.2% of the total hydropower potential of the world and to 14% of European hydropower potential. Only 125 GW of the total hydroelectric potential of Turkey can be economically used. By the commissioning of new hydropower plants, which are under construction, 34% of the economically usable potential of the country would be tapped. At the present, hydropower energy is an important energy source for Turkey due to its useful characteristics such as being renewable, clean, and less of an impact on the environment, and a cheap and domestic energy source.

Kaygusuz, K. [Karadeniz Technical Univ., Trabzon (Turkey). Dept. of Chemistry

1999-08-01

207

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

PubMed Central

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 ?-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.

2012-01-01

208

Extrachromosomal circles of satellite repeats and 5S ribosomal DNA in human cells  

Microsoft Academic Search

BACKGROUND: Extrachomosomal circular DNA (eccDNA) is ubiquitous in eukaryotic organisms and was detected in every organism tested, including in humans. A two-dimensional gel electrophoresis facilitates the detection of eccDNA in preparations of genomic DNA. Using this technique we have previously demonstrated that most of eccDNA consists of exact multiples of chromosomal tandemly repeated DNA, including both coding genes and satellite

Sarit Cohen; Neta Agmon; Olga Sobol; Daniel Segal

2010-01-01

209

An Area-Effective Cell-Based Channel Decoder LSI For a Digital Satellite TV Broadcasting  

Microsoft Academic Search

A new channel decoder LSI, which will be used in digital satellite TV broadcasting Set-Top Boxes, has been designed. This LSI's functions include AD\\/DA conversion, QPSK demodulating, Viterbi decoding, frame synchronization, convolutional deinterleaving, Reed-Solomon (RS) decoding, and descrambling. We use a new method for Viterbi Decoding called the Tracking Survivor State Information (TSSI) method, which not only reduces power consumption,

Takehiro Kamada; Toshihiko Fukuoka; Yuji Nakai; Yoshihiko Fukumoto; Yasuhiro Nakakura; Katsuhiko Ueda; Tomonori Shiomi; Kazuhiro Ota

1998-01-01

210

High Energy Instrumentation Efforts in Turkey  

SciTech Connect

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.

Kalemci, Emrah [Sabanci University, Tuzla, Istanbul (Turkey)

2011-09-21

211

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

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 of PGCs in the zebra finch is of great importance because this species has the potential to become a robust animal model in which to study the function of neuron-glia interactions in healthy and diseased adult brains. PMID:23904989

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

2013-07-25

212

Satellite congestion  

NASA Astrophysics Data System (ADS)

At last count, there were more than 160 satellites in geostationary orbits, circling the earth at an altitude of 37,000 km, and according to a research review published recently by the Rand Corporation, that's already too crowded. The risk of physical collisions among satellites is small, say authors Alvin L. Hiebert and William Sollfrey, but there is an emerging problem with what they call “spectral and orbital congestion,” the result of too many satellites and ground stations sending out too many electromagnetic signals that can interfere with one another.The report comes at a time when the Federal Communications Commission is planning to reduce the spacing between satellites along the U.S. segment of the orbital arc so that 37 additional satellites can be squeezed into the high orbit favored for telecommunications. “As more satellites are launched and others are shifted to avoid collisions, interference problems will get more complicated,” say the authors of the report.

213

Wild Turkey Populations and Management.  

National Technical Information Service (NTIS)

Study Objective: Determine the perceived and actual magnitude of crop damage by wild turkeys and the consequences of expanded hunting opportunity for turkeys in the primary range. Performance: Technology Transfer and Reports. Conduct technology transfer, ...

J. F. Kubisiak

1996-01-01

214

Satellite positioning  

NASA Astrophysics Data System (ADS)

Geodetic positioning programs with the U.S. Navy Transit and GPS satellite systems and satellite laser ranging programs are described. As of 1982 the number of Doppler receivers had increased to over 16,000 units, 1000 with two-frequency geodetic apparatus. The Nova 1 satellite, launched in 1981, was a drag-free satellite, incorporating a single-axis disturbance compensation system (DISCOS) to continuously correct track aberrations due to perturbing forces acting on the satellite. One of the Transit system units, Nova 1 lowered the broadcast ephemeris prediction errors to 5-15 m rms, compared to the 5-70 m rms error for the Oscar satellite. The Navstar GPS system is in full engineering development and will lead to an 18 satellite configuration, with four in view from any point on earth. Global positioning accuracies of 10 m have been found in tests. The Lageos, Starlette, beacon Explorer-C, and Geos-3 satellites have been used in laser ranging experiments to measure polar motions by reflecting laser light from the ground off reflectors on the satellite surfaces. NASA is currently moving a transportable laser station to Easter Island to obtain an accuracy of 10 cm.

Hill, R. W.

1983-04-01

215

Satellite guide  

NASA Astrophysics Data System (ADS)

The University of Rhode Island's Sea Grant Program has published what it calls the first user's guide to environmental satellite data. Written by Peter Cornillon, an oceanographer at Rhode Island, the guide spells out which agencies distribute information from 14 environmental satellites. For those unfamiliar with remote-sensing techniques, the guide also delineates the various sensors the satellites carry and the types of information they produce. The heart of the looseleaf-formatted guide is an overview of the characteristics and objectives of each satellite and the characteristics of the data available.

216

Transcriptional profiling identifies differentially expressed genes in developing turkey skeletal muscle  

PubMed Central

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 involved in extracellular matrix regulation, cell death/apoptosis, and calcium signaling/muscle function, as well as genes with miscellaneous function was confirmed by qPCR. Conclusions The current study identified gene pathways and uncovered novel genes important in turkey muscle growth and development. Future experiments will focus further on several of these candidate genes and the expression and mechanism of action of their protein products.

2011-01-01

217

Comparison of ANN and MLR models for estimating solar radiation in Turkey using NOAA/AVHRR data  

NASA Astrophysics Data System (ADS)

In this paper, the estimation capacities of MLR and ANN are investigated to estimate monthly-average daily SR over Turkey. The satellite data are used for 73 different locations over Turkey. Land surface temperature, altitude, latitude, longitude and month are offered as the input variables for modeling ANN and MLR to get SR. Estimations of SR are evaluated with the meteorological values by using the statistical bases. The obtained results indicated that the ANN model could achieve a satisfactory performance when compared to the MLR model. Moreover, it is understood that more accurate results in estimation of SR are obtained in the use of satellite data, rather than the use of meteorological station data. Finally, the built ANN model is used to estimate the yearly average of daily SR over Turkey. As a result, satellite-based SR map for Turkey is generated.

?ahin, Mehmet; Kaya, Y?lmaz; Uyar, Murat

2013-03-01

218

Healthy satellites provide quality service  

NASA Astrophysics Data System (ADS)

The procedures used by Telesat Canada to ensure the performance of Anik satellites is described. At the Satellite Telemetry, Tracking and Command station, each Anik satellite has its own dedicated antenna. Telemetered information from the satellites is received, processed and forwarded to the Satellite Control Center. There the satellite controllers issue all commands to the satellites, and continually monitor the telemetered data. These data, describing the state of health of the satellites, are then analyzed by engineering specialists. The satellites are held in their precise orbital positions by means of specially developed software. The Anik C and D satellites employ travelling wave tube amplifiers (TWTAs) in the transpounder channels. The TWTA saturated flux density (SFD) and equivalent isotropic radiated power (EIRP) are regularly measured and their trends scrutinized. This ensures that customers receive the radio frequency power needed for high-quality service. The satellite electrical power is supplied by the solar cell array and batteries. Power system performance is evaluated regularly to ensure that power is available to operate the required number of TWTAs. In addition to rain-fades, short service interruptions can be caused by high voltage trip-offs of TWTAs, and by electrostatic discharge related anomalies. To minimize these interruptions, Telesat ensures that the satellite controllers are fully trained and prepared for any eventuality, and the relevant operational procedures are continually refined. A fully trained staff of satellite controllers keep interruptions caused by high voltage trip-offs of TWTAs and by electrostatic discharge to a minimum.

Margittai, Paul

219

Transplanted primary neonatal myoblasts can give rise to functional satellite cells as identified using the Myf5nlacZl+ mouse  

Microsoft Academic Search

Myoblast transplantation is a potential therapeutic approach for the genetic modification of host skeletal muscle tissue. To be considered an effective, long-lived method of delivery, however, it is essential that at least a proportion of the transplanted cells also retain their proliferative potential. We sought to investigate whether transplanted neonatal myoblasts can contribute to the satellite cell compartment of adult

L Heslop; J R Beauchamp; S Tajbakhsh; M E Buckingham; T A Partridge; P S Zammit

2001-01-01

220

Ezh2 maintains a key phase of muscle satellite cell expansion but does not regulate terminal differentiation.  

PubMed

Tissue generation and repair requires a stepwise process of cell fate restriction to ensure that adult stem cells differentiate in a timely and appropriate manner. A crucial role has been implicated for Polycomb-group (PcG) proteins and the H3K27me3 repressive histone mark in coordinating the transcriptional programmes necessary for this process, but the targets and developmental timing for this repression remain unclear. To address these questions, we generated novel genome-wide maps of H3K27me3 and H3K4me3 in freshly isolated muscle stem cells. These data, together with the analysis of two conditional Ezh2-null mouse strains, identified a critical proliferation phase in which Ezh2 activity is essential. Mice lacking Ezh2 in satellite cells exhibited decreased muscle growth, severely impaired regeneration and reduced stem cell number, due to a profound failure of the proliferative progenitor population to expand. Surprisingly, deletion of Ezh2 after the onset of terminal differentiation did not impede muscle repair or homeostasis. Using these knockout models and the RNA-Seq and ChIP-Seq datasets, we show that Ezh2 does not regulate the muscle differentiation process in vivo. These results emphasise the lineage and cell-type-specific functions of Ezh2 and Polycomb repressive complex 2. PMID:23203812

Woodhouse, Samuel; Pugazhendhi, Dhamayanthi; Brien, Patrick; Pell, Jennifer M

2012-11-30

221

Artificial Satellites  

NSDL National Science Digital Library

Over 2,000 man-made satellites are currently orbiting the Earth, providing a wide range of services like communications, remote sensing, and global positioning. As more are launched and new technologies are developed, they will play an increasingly important role in everyday life.The Tech Museum offers this site (1) dedicated to the basics of satellites and their functions. A Java program complements the Satellite Anatomy section, which illustrates the standard components of three different categories of satellites. More information specific to satellite launches and their orbits can be found here (2). Most of the material is composed of fun experiments that demonstrate satellite operation. One of the most interesting features on this NASA site (3) is the Live 3D Java Tracking Display, which shows hundreds of different satellites and their current position in orbit. A few selected news articles and a separate section on satellite applications are also provided. The European Space Agency provides a look at solar power satellites (4), which could essentially "beam" energy to Earth. While it is not a new concept, the sheer magnitude of a project to construct a solar power satellite has thus far been too great to justify an attempt. At a conference held in December 2002 (5), representatives from the satellite industry convened to discuss current developments. Although many of the articles only address industry outlooks, some are more technology-oriented. For instance, one considers a new navigation system that could improve overall coverage and signal availability. A lesson plan (6) for grades K-5 teaches children how satellites are launched and some basic terminology. The activity uses different sized marbles, clay, and some other items to demonstrate fundamental concepts. Satellites of the Global Positioning System are being used for more than they were originally intended in England. This news article (7) describes how they are used to study earthquakes and corresponding movements in the Earth's crust. In other news (8), the largest communications satellite ever built was lost in November 2002. The failure of one of its launching rockets resulted in the satellite falling in a decaying orbit until it fell into the sea.

Leske, Cavin.

2003-01-01

222

Intramuscular Transplantation of Human Postnatal Myoblasts Generates Functional Donor-Derived Satellite Cells  

Microsoft Academic Search

Myogenic cell transplantation is an experimental approach for the treatment of myopathies. In this approach, transplanted cells need to fuse with pre-existing myofibers, form new myofibers, and generate new muscle precursor cells (MPCs). The last property was fully reported following myoblast transplantation in mice but remains poorly studied with human myoblasts. In this study, we provide evidence that the intramuscular

Daniel Skuk; Martin Paradis; Marlyne Goulet; Pierre Chapdelaine; David M Rothstein; Jacques P Tremblay

2010-01-01

223

Cellular Cardiomyoplasty Using Autologous Satellite Cells: from Experimental to Clinical Study  

Microsoft Academic Search

Abstract Adult mammalian ventricular myocytes lack regenerative capability, consequently an in- jured heart is normally repaired by scar formation, hypertrophy of surviving myocytes, and hyperplasia of non-muscle cells. The possible existence of stem cells or progenitor cells for myocardium has been suggested recently, however it is clear that functionally significant myocardial regeneration has not been documented,in diseased or injured heart.

Race L. Kao; Fumin Zhang; Zhi-jian Yiang; Xiang Gao; Chuanfu Li

224

Biotechnological developments in Turkey  

SciTech Connect

Turkey is a country not usually associated with industrial biotechnology. However, when current research potential in universities and other R and D centers and particularly contributions made to the international literature since the mid-1980s are taken into account, high-quality international-level work is now commonplace, especially in areas such as industrial microbiology, enzyme technology, biomaterials and biological wastewater treatment. Work in plant biotechnology is at a relatively early stage, but is expected to become a rapidly developing force in the near future. The present article documents current potential in Turkey, based on significant publications produced during the last 8 years. 268 refs.

Oezcengiz, G. [Middle East Technical Univ., Ankara (Turkey). Dept. of Biological Sciences

1996-05-01

225

Testosterone inhibits transforming growth factor-? signaling during myogenic differentiation and proliferation of mouse satellite cells: Potential role of follistatin in mediating testosterone action  

PubMed Central

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

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

2012-01-01

226

Bmi1 Is Expressed in Postnatal Myogenic Satellite Cells, Controls Their Maintenance and Plays an Essential Role in Repeated Muscle Regeneration  

PubMed Central

Satellite cells are the resident stem cell population of the adult mammalian skeletal muscle and they play a crucial role in its homeostasis and in its regenerative capacity after injury. We show here that the Polycomb group (PcG) gene Bmi1 is expressed in both the Pax7 positive (+)/Myf5 negative (?) stem cell population as well as the Pax7+/Myf5+ committed myogenic progenitor population. Depletion of Pax7+/Myf5? satellite cells with reciprocal increase in Pax7+/Myf5+ as well as MyoD positive (+) cells is seen in Bmi1?/? mice leading to reduced postnatal muscle fiber size and impaired regeneration upon injury. Bmi1?/? satellite cells have a reduced proliferative capacity and fail to re-enter the cell cycle when stimulated by high serum conditions in vitro, in keeping with a cell intrinsic defect. Thus, both the in vivo and in vitro results suggest that Bmi1 plays a crucial role in the maintenance of the stem cell pool in postnatal skeletal muscle and is essential for efficient muscle regeneration after injury especially after repeated muscle injury.

Radunovic, Aleksandar; Bird, Katy; Zhang, Xinyu; Marino, Silvia

2011-01-01

227

Cloning Creationism in Turkey.  

ERIC Educational Resources Information Center

|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…

Edis, Taner

1999-01-01

228

Special education in Turkey  

Microsoft Academic Search

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 article presents the developments and current status of special education

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

2009-01-01

229

Wind energy in Turkey  

Microsoft Academic Search

Wind and wind energy has always played an important role in the historical and economical development of Asia Minor and the geographical area covered by the Republic of Turkey today. The ancient city of Troia probably became rich with harbor fees from commercial vessels, which could not sail up the Dardanelles because of strong north-easterly winds and swift currents. As

Mehmet Hana?asio?lu

1999-01-01

230

Future of Secular Turkey.  

National Technical Information Service (NTIS)

This research paper is a study of the prospects of a secular state developing in Turkey since the Refah Party, an Islamist party, has come to lead a coalition government with the secular True Path Party. The origins of the secular Turkish state will be ex...

D. A. Mayo

1997-01-01

231

Feather the Turkey.  

ERIC Educational Resources Information Center

Presents a cut-and-paste turkey puzzle for students to use that combines the use of card or automated catalog records with the Thanksgiving theme. Students are given Thanksgiving topics and asked to find subjects, titles, authors, or keywords in order to assemble the puzzle. (LRW)

School Library Media Activities Monthly, 1996

1996-01-01

232

Turkey's Biogas Energy Potential  

Microsoft Academic Search

As in the rest of the world, in Turkey it is necessary to utilize the renewable energy sources to make up for the increasing energy deficit. As an alternative to these energy sources, the use of biogas seems possible. Even when it is considered only with regards to the animal husbandry sector, the majority of the manure obtained is a

N. Kizilaslan; H. Kizilaslan

2007-01-01

233

Special Education in Turkey  

ERIC Educational Resources Information Center

|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…

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

2009-01-01

234

Development of a 12 ampere-hour sealed silver-zinc cell for satellite applications  

Microsoft Academic Search

Cells incorporating the latest parameters of the sealed silver-zinc system were designed and cycle tested. Early designs failed after 50 cycles. A poor charge acceptance at high current density was due to electrolyte starvation in the positive compartment. To facilitate the electrolyte diffusion to the positive plates, low-concentration KOH was used. It extended the cycling life of the cells but

Serenyi

1964-01-01

235

Immune responses of turkey poults with turkey poult enteritis  

Microsoft Academic Search

A turkey coronavirus (TCV) isolate associated with turkey poults with acute enteritis was identified and characterized by morphological, serological, and, molecular properties. Sephacryl S-1000 size-exclusion chromatography was found to be a useful method for purification of TCV from turkey embryo intestines. However, results of antibody-capture enzyme-linked immunosorbent assay (ELISA) coated with TCV antigens prepared from infected intestines were inconsistent. Alternatively,

Chien Chang Loa

2000-01-01

236

Activation State of Muscle Satellite Cells Isolated from Steers Implanted with a Combined Trenbolone Acetate and Estradiol Implant1,2  

Microsoft Academic Search

Muscle satellite cells were isolated from seven yearling steers implanted for 31 d with a combined implant that contained 120 mg of trenbolone acetate (TBA) and 24 mg of estradiol (E 2) and from seven nonimplanted, control steers. Implanted steers had a 28% greater ADG and a 23% greater feed efficiency than did nonimplanted steers. Implanted steers had increased (

B. J. Johnson; N. Halstead; M. E. White; M. R. Hathaway; A. DiCostanzo; W. R. Dayton

2010-01-01

237

Induction of Cardiac Myogenic Lineage Development Differs between Mesenchymal and Satellite Cells and is Accelerated by Bone Morphogenetic Protein-4  

PubMed Central

Our aim was to further elucidate the cardiac lineage development of bone marrow-derived mesenchymal stem cells (MSC) and to identify cells which had the potential for cardiac myogenic differentiation when compared to skeletal muscle satellite (Sk-sat) myogenesis. Unlike Sk-sat, MSC expressed the early cardiac markers Nkx2.5 and GATA4. Their expression was significantly increased by culturing MSC with Bone Morphogenetic Protein 4 (BMP4). Enhanced cardiac myogenic lineage differentiation and loss of stem cell characteristics induced by BMP4 were further confirmed by flow cytometry of cells stained for Nkx2.5 and Sca-1 expression. MSC also expressed skeletal genes (MyoG, ssTnI, Sk-Act) early in culture but their expression was suppressed when BMP4 was added from day 0–6 (p < 0.05). BMP4 treated MSC also exhibited a 6-fold increase in cTnI expression by day 12 in culture. The average MSC action potential time duration at 90% (APD90) was 32.3 ± 4 ms, with some cells exhibiting action potentials closer to Sk-sat APD90 of 13.7 ± 0.9 ms. After treatment with BMP4, MSC significantly increased their APD90 to 54.4 ± 7.6 ms, shifting from the shorter skeletal-like signature, towards a longer action potential duration more characteristic of a cardiomyocyte signature. Our results show that MSC and Sk-sat exhibit similarities in myogenic lineage development early in culture but that BMP4 clearly enhances cardiac myogenic development, suppresses skeletal myogenesis, and leads to loss of “stemness” in MSC. These findings provide novel information regarding the use of BMP4 to accelerate cardiac myogenic development in harvested MSC and further support the use of MSC in cardiac regenerative therapy.

Grajales, Liliana; Garcia, Jesus; Geenen, David L.

2012-01-01

238

Relaxin regulates MMP expression and promotes satellite cell mobilization during muscle healing in both young and aged mice.  

PubMed

The polypeptide hormone relaxin has been proven to be effective in promoting both the remodeling and regeneration of various tissues, including cardiac muscle. In addition, our previous study demonstrated that relaxin is beneficial to skeletal muscle healing by both promoting muscle regeneration and preventing fibrosis formation. However, the molecular and cellular mechanisms of relaxin in regulating both myogenic cell differentiation and muscle healing process are still unclear. In this study, C2C12 mouse myoblasts and primary human myoblasts were treated with relaxin to investigate its potential effect in vitro; relaxin was also injected intramuscularly into the injured site of the mouse on the second day after injury to observe its function in vivo, especially in the aged muscle. Results showed that relaxin promoted myogenic differentiation, migration, and activation of matrix metalloproteinases (MMPs) of cultured myoblasts in vitro. In the injured muscle, relaxin administration promoted the activation of Pax7-positive skeletal muscle satellite cells and increased its local population compared with nontreated control muscles. Meanwhile, both angiogenesis and revascularization were increased, while the extended inflammatory reaction was repressed in the relaxin-treated injured muscle. Moreover, relaxin similarly promoted muscle healing in mice with aged muscle. These results revealed the multiple effects of relaxin in systematically improving muscle healing as well as its potential for clinical applications in patients with skeletal muscle injuries and diseases. PMID:20934971

Mu, Xiaodong; Urso, Maria L; Murray, Kiley; Fu, Freddie; Li, Yong

2010-10-07

239

Cycle life evaluation of 3Ah LiMnO-based lithium-ion secondary cells for low-earth-orbit satellites. II. Harvested electrode examination  

Microsoft Academic Search

Lithium-ion batteries are a candidate for the energy storage system onboard low-earth-orbit satellites. Terrestrial experiments are able to capture the performance degradation of cells in orbit, therefore providing the opportunity for lifetime investigations. The lifetime performance of 3 Ah commercial LiMnO-based pouch cells was evaluated in a matrix of different cycling depths-of-discharge (DODs: 0, 20, 40%) and temperatures (25, 45

S. Brown; K. Ogawa; Y. Kumeuchi; S. Enomoto; M. Uno; H. Saito; Y. Sone; D. Abraham; G. Lindbergh

2008-01-01

240

Cycle life evaluation of 3 Ah Li x Mn 2O 4-based lithium-ion secondary cells for low-earth-orbit satellites  

Microsoft Academic Search

Lithium-ion batteries are a candidate for the energy storage system onboard low-earth-orbit satellites. Terrestrial experiments are able to capture the performance degradation of cells in orbit, therefore providing the opportunity for lifetime investigations. The lifetime performance of 3Ah commercial LixMn2O4-based pouch cells was evaluated in a matrix of different cycling depths-of-discharge (DODs: 0, 20, 40%) and temperatures (25, 45°C). Aged

Shelley Brown; Keita Ogawa; Youichi Kumeuchi; Shinsuke Enomoto; Masatoshi Uno; Hirobumi Saito; Yoshitsugu Sone; Daniel Abraham; Göran Lindbergh

2008-01-01

241

Bordetella avium causes induction of apoptosis and nitric oxide synthase in turkey tracheal explant cultures  

Microsoft Academic Search

Bordetellosis is an upper respiratory disease of turkeys caused by Bordetella avium in which the bacteria attach specifically to ciliated respiratory epithelial cells. Little is known about the mechanisms of pathogenesis of this disease, which has a negative impact in the commercial turkey industry. In this study, we produced a novel explant organ culture system that was able to successfully

David M. Miyamoto; Kristin Ruff; Nathan M. Beach; Stephanie B. Stockwell; Angella Dorsey-Oresto; Isaac Masters; Louise M. Temple

2011-01-01

242

Wind energy and Turkey  

Microsoft Academic Search

The global energy requirement for sustaining economic activities, meeting social needs and social development is increasing\\u000a daily. Environmentally friendly, renewable energy resources are an alternative to the primary non-renewable energy resources,\\u000a which devastate ecosystems in order to meet increasing demand. Among renewable energy sources such as hydropower, biopower,\\u000a geothermal power and solar power, wind power offers distinct advantages to Turkey.

Aynur Aydin Coskun; Yavuz Özhan Türker

243

THE PATHOGENESIS OF TURKEY ORIGIN REOVIRUSES IN TURKEYS AND CHICKENS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Avian reoviruses that have been shown to be genetically distinct from chicken origin reoviruses were isolated from commercial turkey flocks in the Southeastern U.S. and Texas which were experiencing enteritis. These turkey origin reoviruses (TRV's) were evaluated for their pathogenesis in commercial...

244

[Stranger in Turkey].  

PubMed

The author, a professor of nephrology, reports some impressions of his 7-year stay in Turkey. He worked at the Ege University in Izmir, traditionally one of the most 'western' cities. He and his wife, who gave unpaid assistance to dialysis patients, attempted to integrate into Turkish society as fully as possible. They traversed the country in weekends and holidays and introduced as many Dutch guests as they could to the unique archeological treasures, the magnificent nature and the extremely friendly population. Work at the university focused increasingly on cultivating a critical attitude with regard to the self, society and the trends and commercialization of medicine in Turkey and in the rest of the world. Self-reliance, also, had to be strengthened. Although this contravened the authority-based Turkish educational system, the efforts were clearly appreciated and even stirred enthusiasm in many of the younger people. There is no doubt that a foreign worker is regarded much more favourable in Turkey than in the Netherlands. PMID:9555146

Dorhout Mees, E J

1997-12-20

245

Satellite Telecommunications.  

ERIC Educational Resources Information Center

|This issue of a quarterly publication of the Council of Europe covers aspects of the history, technology, policies, and impact of telecommunications in Europe, with an emphasis on European television. The following articles are included: (1) "Man and the World of Telecommunications" (Piet Stoffelen); (2) "The European Communications Satellite

Forum, 1986

1986-01-01

246

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

SciTech Connect

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.

Masumoto, Hiroshi; Sugimoto, Kenji; Okazaki, Tuneko (Nagoya Univ. (Japan))

1989-03-01

247

Epidemiology of pityriasis versicolor in Adana, Turkey.  

PubMed

Pityriasis versicolor is a common superficial mycoses of the skin. It is now recognized that the causative organisms of this infection are different species of Malassezia. The aim of this study was to determine the distribution of Malassezia species in patients with pityriasis versicolor in Adana, Turkey. In total, 97 patients positive for Malassezia elements, namely, yeast cells and short hyphae in microscopic examination, were included in the study. All samples were inoculated in plates containing modified Dixon's medium. However, only 44 of the patients (45.4%) showed Malassezia spp. in culture. Malassezia globosa (47.7%) was the most commonly isolated species followed by Malassezia furfur (36.4%) and Malassezia slooffiae (15.9%). Mixed Malassezia species were not isolated. In conclusion, M. globosa was found to be the predominant PV isolate in Adana, Turkey. PMID:19583685

Karaka?, Mehmet; Turaç-Biçer, Aygül; Ilkit, Macit; Durdu, Murat; Seydao?lu, Gül?ah

2009-07-01

248

Refugee movements and Turkey.  

PubMed

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 rights. Europe in return has tightened legislation and procedures to differentiate economically motivated refugees from authentic political asylum seekers. Further research is needed to investigate refugee problems. Further refugees may come due to the promotion of a Black Sea Cooperation Region and easier crossings of borders to the former Soviet Republics. Ethnic Turks in Moldavia or Romania or Bulgaria may leave due to unrest. Factors affecting asylum seekers are improvements in Turkey's human rights record, repeal of bans of the Kurdish language, completion of the South Eastern Development Project, and the European government policy on asylum. PMID:12285110

Kirisci, K

1991-12-01

249

Lamin A/C and emerin are critical for skeletal muscle satellite cell differentiation  

PubMed Central

Mutations within LMNA, encoding A-type nuclear lamins, are associated with multiple tissue-specific diseases, including Emery-Dreifuss (EDMD2/3) and Limb-Girdle muscular dystrophy (LGMD1B). X-linked EDMD results from mutations in emerin, a lamin A-associated protein. The mechanisms through which these mutations cause muscular dystrophy are not understood. Here we show that most, but not all, cultured muscle cells from lamin A/C knockout mice exhibit impaired differentiation kinetics and reduced differentiation potential. Similarly, normal muscle cells that have been RNA interference (RNAi) down-regulated for either A-type lamins or emerin have impaired differentiation potentials. Replicative myoblasts lacking A-type lamins or emerin also have decreased levels of proteins important for muscle differentiation including pRB, MyoD, desmin, and M-cadherin; up-regulated Myf5; but no changes in Pax3, Pax7, MEF2C, MEF2D, c-met, and ?-catenin. To determine whether impaired myogenesis is linked to reduced MyoD or desmin levels, these proteins were individually expressed in Lmna–/– myoblasts that were then induced to undergo myogenesis. Expression of either MyoD or, more surprisingly, desmin in Lmna–/– myoblasts resulted in increased differentiation potential. These studies indicate roles for A-type lamins and emerin in myogenic differentiation and also suggest that these effects are at least in part due to decreased endogenous levels of other critical myoblast proteins. The delayed differentiation kinetics and decreased differentiation potential of lamin A/C-deficient and emerin-deficient myoblasts may in part underlie the dystrophic phenotypes observed in patients with EDMD.

Frock, Richard L.; Kudlow, Brian A.; Evans, Angela M.; Jameson, Samantha A.; Hauschka, Stephen D.; Kennedy, Brian K.

2006-01-01

250

Crop drying programme in Turkey  

Microsoft Academic Search

The present status of agricultural crop drying practices in Turkey is investigated in this study. The emphasis of drying on market value, annual production and export values of some commercially important crops is given in a broad perspective. In the recent years, developing international market conditions in Europe, Middle East, and Central Asia has been encouraging to Turkey's fresh and

Y. Soysal

1999-01-01

251

The earthquake catalog of Turkey  

Microsoft Academic Search

The Development Project for the Historical Earthquake Catalog of Turkey and related sources are introduced and the characteristics of the catalog determined. As an example, Ottoman sources are given. Multidisciplinary characteristics of seismology and the necessity for the reorganization of the Republic of Turkey Prime Ministery Archives are pointed out. While discussing forecasting problems, the benefits of knowing how to

H. Soysal

1979-01-01

252

Solar Energy Applications in Turkey  

Microsoft Academic Search

Solar energy technologies offer a clean, renewable and domestic energy source, and are essential components of a sustainable energy future. Turkey lays in a sunny belt between 36° and 42° N latitudes and is geographically well situated with respect to solar energy potential. The objective of the present study is to investigate many aspects of solar energy applications in Turkey,

ARIF HEPBASLI; KORAY ULGEN; RUSTU EKE

2004-01-01

253

Turkey between national and theater missile defense  

Microsoft Academic Search

Turkey, sharing borders with Iraq and Iran, is becoming increasingly involved with the US and Israel, its post-Cold War strategic partners, in the Middle Eastern TMD project. Turkey's regional security concerns, and dependency on the US - which is partly caused by Turkey's exclusion from the European integration - provides the leverage for American pressure on Turkey to participate in

Isil Kazan

2002-01-01

254

Turkey's energy demand and supply  

SciTech Connect

The aim of the present article is to investigate Turkey's energy demand and the contribution of domestic energy sources to energy consumption. Turkey, the 17th largest economy in the world, is an emerging country with a buoyant economy challenged by a growing demand for energy. Turkey's energy consumption has grown and will continue to grow along with its economy. Turkey's energy consumption is high, but its domestic primary energy sources are oil and natural gas reserves and their production is low. Total primary energy production met about 27% of the total primary energy demand in 2005. Oil has the biggest share in total primary energy consumption. Lignite has the biggest share in Turkey's primary energy production at 45%. Domestic production should be to be nearly doubled by 2010, mainly in coal (lignite), which, at present, accounts for almost half of the total energy production. The hydropower should also increase two-fold over the same period.

Balat, M. [Sila Science, Trabzon (Turkey)

2009-07-01

255

Targeted suppression of ?-calpain and caspase 9 expression and its effect on caspase 3 and caspase 7 in satellite cells of Korean Hanwoo cattle.  

PubMed

The calpains play an important role in cell death and cell signalling. Caspases catalyse wholesale destruction of cellular proteins which is a major cause of cellular death. The current study looks at the function of ?-calpain and caspase 9, using RNAi (RNA interference)-mediated silencing, and to observe the mRNA expression level of caspase genes during satellite cell growth. The satellite cells were treated with siRNA (small interfering RNA) of ?-calpain and caspase 9 separately. There was reduction of 16 and 24% in CAPN1 (calpain1)-siRNA2 and CAPN1-siRNA3 transfected cells respectively, whereas it was 60 and 56% in CAPN1-siRNA1 and CAPN1-siRNA4 transfected cells respectively. CAPN1-siRNA4 and CAPN1-siRNA1 treated cells showed more reduction in caspase 3 and 7 gene expression. CARD9 (caspase recruitment domain 9)-siRNA1 and CARD9-siRNA2-treated cells showed reduction of 40 and 49% respectively. CARD9-siRNA1 and CARD9-siRNA2 showed an increase in caspase 3 gene expression, whereas CARD9-siRNA2 showed reduction in caspase 7 gene expression. These results suggest a strong cross-talk between ?-calpain and the caspase enzyme systems. Suppression of target genes, such as ?-calpain and caspase 9, might have genuine potential in the treatment of skeletal muscle atrophy. PMID:22657938

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

2012-09-01

256

New multiple labelling method for improved satellite cell identification in human muscle: application to a cohort of power-lifters and sedentary men  

Microsoft Academic Search

Presently applied methods to identify and quantify human satellite cells (SCs) give discrepant results. We introduce a new\\u000a immunofluorescence method that simultaneously monitors two SC markers (NCAM and Pax7), the basal lamina and nuclei. Biopsies\\u000a from power-lifters, power-lifters using anabolic substances and untrained subjects were re-examined. Significantly different\\u000a results from those with staining for NCAM and nuclei were observed. There

Mona Lindström; Lars-Eric Thornell

2009-01-01

257

Influence of low-intensity magnetic fields on the development of satellite muscle cells of a newborn rat in primary culture  

Microsoft Academic Search

The influence of Earth magnetic field shielded down to 0.3 ?T and static magnetic field (60–160 ?T) on the proliferation and\\u000a differentiation of satellite muscle cells in primary culture has been investigated. A stimulatory effect of static magnetic\\u000a fields on the rate of the formation of massive multinucleate myotubes and an increase in the intracellular calcium concentration\\u000a ([Ca2+]\\u000a i\\u000a )

I. S. Eldashev; B. F. Shchegolev; S. V. Surma; G. B. Belostotskaya

2010-01-01

258

Potential role of G-protein-coupled receptor 30 (GPR30) in estradiol-17?-stimulated IGF-I mRNA expression in bovine satellite cell cultures  

Microsoft Academic Search

Androgenic and estrogenic steroids enhance muscle growth in animals and humans. Estradiol-17? (E2) and trenbolone acetate (TBA) (a synthetic testosterone analog) increased IGF-I mRNA expression in bovine muscle satellite cell (BSC) cultures. The goal of this study was to evaluate the mechanisms responsible for this increase by evaluating the effects of ICI 182 780 (an E2 receptor antagonist), flutamide (an

E. Kamanga-Sollo; M. E. White; K. Y. Chung; B. J. Johnson; W. R. Dayton

2008-01-01

259

Glucose induces de novo lipogenesis in rat muscle satellite cells through a sterol-regulatory-element-binding-protein-1c-dependent pathway  

Microsoft Academic Search

We previously reported that sterol-regulatory-element- binding-protein-1c (SREBP-1c) mediates insulin upregulation of genes encoding glycolytic and lipogenic enzymes in rat skeletal muscle. Here, we assessed whether glucose could regulate gene expression in contracting myotubes deriving from cultured muscle satellite cells. Glucose uptake increased twofold after a 30 minute treatment with a high glucose concentration, suggesting an acute glucose-stimulated glucose uptake. Time-course

Isabelle Guillet-Deniau; Anne-Lise Pichard; Aminata Koné; Catherine Esnous; Myriam Nieruchalski; Jean Girard; Carina Prip-Buus

2004-01-01

260

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

PubMed

The current study was conducted to evaluate the functions of ?-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

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

2012-05-31

261

How Satellites Work  

NSDL National Science Digital Library

Collection of seven classroom activities that focus on satellite technology. Topics include: coordinated universal time (UTC); satellite pass prediction; satellite design; satellite orbits; satellite launching; and, use of satellites in at-sea rescues. Each activity provides list of materials needed, background information, and procedure.

262

Dynamic between National Identity and Foreign Policy in Turkey.  

National Technical Information Service (NTIS)

Recently, Turkey's foreign policy has undergone some considerable changes. In order to understand why this has occurred, and where Turkey's foreign policy will likely go in the future, one must examine Turkey's national identity. Today, Turkey's dominant ...

I. W. Bullen

2009-01-01

263

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

PubMed

Loss of myonuclei by apoptosis is thought to contribute to sarcopenia. We have previously shown, that the leucine metabolite, ?-hydroxy-?-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 34month old Fisher 344×Brown Norway rats were unloaded for 14days by hindlimb suspension (HLS), and then reloaded for 14days. The rats received either Ca-HMB (340mg/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 HMB improved the proliferation of muscle stem cells in fast twitch plantaris muscles. Enhanced satellite cell proliferation leading to increased differentiated myonuclei should increase the transcriptional potential to support muscle hypertrophic changes and functional changes in sarcopenic muscles, and this could partly explain the reduced apoptotic index in HMB treated muscles. Indeed, muscle mass and fiber cross-sectional area were significantly greater in plantaris muscles from HMB-treated animal muscles after reloading as compared to vehicle-treated animals. PMID:23832076

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

2013-07-04

264

Satellite-to-satellite tracking orbit determination  

Microsoft Academic Search

In the 1980's, low-earth-satellite orbits will be determined from one-way or relayed range and range-rate measurements to high-altitude orbiting spacecraft such as the two geo-synchronous satellites in the NASA Tracking and Data Relay Satellite System (TDRSS) and the 24 twelve-hour period, 63 deg inclination spacecraft in the DOD Global Positioning System (GPS). In this study, error analysis methods for satellite-to-satellite

B. T. Fang

1978-01-01

265

Turkey's foreign dependence on energy  

SciTech Connect

Turkey becomes more dependent on the external countries in energy production every year. As an average of the period 1994-2002 the total primary energy production has been 27.9 Mtoe, and consumption has been 73.06 Mtoe, so Turkey is dependent on external countries in petroleum, natural gas, and hard coal consumption. The external dependency rate of these fuels has been at levels of 89.3%, 96.6%, and 82%, respectively. In the projections of Turkey for 2020, the primary energy consumption is estimated to be 298 Mtoe, production is estimated to be 70 Mtoe, the ratio of production to consumption will be reduced to 23.5%, and this situation will cause serious risks for sustainable development. In other words, Turkey will have to import 76.5% of the energy that it consumes in the 2020s.

Uslu, T. [Karadeniz Technical University, Trabzon (Turkey). Dept. of Mining Engineering

2008-07-01

266

Turkey and European Security Institutions.  

National Technical Information Service (NTIS)

Turkey's relationships with the West, particularly its relationship with Western security institutions, are today more important than ever. As the United States fights two wars in the region and attempts to rebuild its reputation in Europe and the Middle ...

A. M. Scheer

2009-01-01

267

U.S. Turkey Industry.  

National Technical Information Service (NTIS)

Americans are eating more turkey than ever because of lower real prices and new products. Production and consumption have expanded principally in the off season; both are now year-round activities. Further processed products represent the fastest growing ...

F. A. Lasley W. L. Henson H. B. Jones

1985-01-01

268

Domestic livestock resources of Turkey  

Microsoft Academic Search

Water buffalo are an ancient component of Turkey’s domestic livestock resources. Commonly referred to as the Anatolian buffalo\\u000a the animal is part of the Mediterranean group which includes Syrian, Egyptian and Southeast European animals. Once quite numerous,\\u000a there have been drastic reductions in their numbers since the 1970s due to intensification of dairy activities, agricultural\\u000a mechanization and changing consumer preferences.

Orhan Yilmaz; Mehmet Ertugrul; Richard Trevor Wilson

269

Rare Hemoglobin Variant Hb Yaizu Observed in Turkey  

Microsoft Academic Search

Objective: To determine the characteristic features of the rare hemoglobin (Hb) variant Hb Yaizu to enable laboratory diagnosis of the hemoglobin variants during screening programs. Materials and Methods: Genomic DNA was obtained from the 4 members of a family living in Denizli province, an Aegean region of Turkey. Blood cell counts, hemoglobin composition, hemoglobin electrophoresis (both alkaline and acid), HPLC

Erol Ömer Atalay; Ayfer Atalay; Hasan Koyuncu; Onur Öztürk; Aylin Köseler; Anzel Özkan; Sanem Demirtepe

2008-01-01

270

Devastating Earthquake in Turkey  

NSDL National Science Digital Library

The death toll will pass 10,000 today from Tuesday's earthquake, which measured 7.4 on the Richter scale and shattered a 400-mile stretch from northwestern Turkey to areas near central Ankara. Relief officials have publicly stated that they fear the worst for the estimated 35,000 people who remain trapped beneath rubble, as most will now have been without water for more than 72 hours. In addition to locating and rescuing survivors, the Turkish Government and international aid workers are working feverishly to organize relief efforts, prevent the spread of disease, repair damaged infrastructure, and contain a massive fire at the country's largest oil refinery. The sites listed provide information about this horrible act of nature

De Nie, Michael W.

271

Feasibility of microminiature satellites  

Microsoft Academic Search

A conceptual study is conducted on technical problems and system design techniques to accomplish higher performance microminiature satellites by smaller systems. Applications of microminiature satellite technology to practical satellite mission are mentioned. Concepts of microminiature satellites, measures to miniaturize satellites, and micro-miniaturization technologies for communication and data processing, electric solar power paddle, attitude and orbit control, structure, thermal control, propulsion,

Ryouichi Imai

1991-01-01

272

Outer planet satellites  

Microsoft Academic Search

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.

Paul M. Schenk

1991-01-01

273

Mitotic recombination and segregation of satellites in Bloom's syndrome  

Microsoft Academic Search

Mitotic recombination in satellite stalks — a phenomenon often difficult to distinguish from satellite association — was studied in a sister and a brother with Bloom's syndrome. Segregation after recombination was analyzed in the lymphocytes of the sister who had Q-bright satellites. Her cells varied greatly both in regard to the acrocentrics which displayed Q-bright satellites and the number of

Eeva Therman; Priscila G. Otto; Nasrollah T. Shahidi

1981-01-01

274

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

SciTech Connect

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.

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

1980-01-01

275

Isolation and serological studies with infectious bursal disease viruses from fowl, turkeys and ducks: Demonstration of a second serotype  

Microsoft Academic Search

The isolation of a number of strains of infectious bursal disease (IBD) virus from fowl, turkeys and ducks is described. These isolates could be grouped into two serotypes using the neutralisation test. It is proposed that the cell culture adapted vaccine strain from fowl should be the prototype virus for serotype 1 and that the TY89 isolate from a turkey

J. B. McFerran; M. S. McNulty; E. R. McKillop; T. J. Connor; R. M. McCracken; D. S. Collins; G. M. Allan

1980-01-01

276

Declines in phytoplankton cell size in the subtropical oceans estimated from satellite remotely-sensed temperature and chlorophyll, 1998-2007  

NASA Astrophysics Data System (ADS)

Satellite remotely-sensed sea surface temperature (SST) and surface chlorophyll were used to estimate median phytoplankton cell size at monthly and 11 km2 resolution over the global ocean, 1998-2007. The temporal dynamics of median phytoplankton cell size were examined for the Pacific equatorial upwelling region and the subtropical oceans. For the equatorial upwelling region, cell size varied coherently with the El Niño Southern Oscillation with smaller (larger) median cell size during El Niños (La Niñas). Specifically, estimated median cell diameter increased by 34% between the 1998 El Nino and the 1999-2001 La Nina. In the subtropical oceans, over the period 1998-2007, median cell diameter exhibited statistically significant linear declines of about 2% in the North and South Pacific, and 4% in the North Atlantic. Pooling the data over all subtropical oceans, over the period 1998-2007, global median cell diameter declined by about 2%. These results suggest that phytoplankton cell size may vary on interannual and decadal scales resulting in changes in food chain length and hence energy transfer to higher trophic levels. Further, a shift to smaller sized phytoplankton has been hypothesized as a response to ocean warming. Thus, this approach, estimating phytoplankton cell size from remotely-sensed temperature and chlorophyll, has the potential to provide global monitoring of an aspect of phytoplankton community structure likely to be responsive to future climate change.

Polovina, Jeffrey J.; Woodworth, Phoebe A.

2012-11-01

277

Investigation of Earthquakes in Turkey Using GIS  

Microsoft Academic Search

There are three main active faults in Turkey: the North Anatolian Fault (NAF), the Northeast Anatolian Fault (NEAF) and the East Anatolian Fault (EAF). NAF is one of the most active seismic regions over the world, runs along the northern part of Turkey about 1500 km, from the Aegean to the Karliova triple junction in the eastern Turkey. It has

A. Garagon Dogru; H. Ozener

2005-01-01

278

Management Plan for Wild Turkeys in Pennsylvania.  

National Technical Information Service (NTIS)

The wild turkey (Meleagris gallopavo) is native to North America. Of six subspecies, the eastern wild turkey (M. g. silvestris) is the only one to have occurred in Pennsylvania. Wild turkeys are our largest gallinaceous game bird. The males, or gobblers, ...

W. E. Drake

1999-01-01

279

Assessing Poverty and Related Factors in Turkey  

Microsoft Academic Search

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 Hu- man Development Report. The individual

Esra Saatci; Ersin Akpinar

280

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

ERIC Educational Resources Information Center

|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…

Moyer, Richard; Everett, Susan

2009-01-01

281

FACTORS AFFECTING MITOGENIC RESPONSE OF TURKEY LYMPHOCYTES  

Microsoft Academic Search

Loa C. C., T. L. Lin, C. C. W u: Factors Affecting Mitogenic Response of Turkey Lymphocytes. Acta Vet. Brno 2001, 70: 433-442. The objective of the present study was to determine the parameters and conditions for measuring mitogenic response of turkey whole blood and spleen lymphocytes that may be useful in studying cellular immunity of turkeys. Heparinized whole blood

C. C. LOA; T. L. LIN; C. C. WU

2001-01-01

282

Observation or telecommunication satellites  

US Patent & Trademark Office Database

The low earth orbit radar remote sensing or telecommunication satellite includes an antenna forming member in a plane passing through the center of Earth, for example, the plane of its orbit. The antenna(s) are on one or both faces of the member. The height of the antenna forming member is greater than its dimension in the direction of travel of the satellite, so that the satellite is naturally stabilized by the gravity gradient. The solar generator cells are carried by the antenna forming member on the face that is kept facing towards the Sun in the case of a 6 H/18 H local time heliosynchronous orbit. The antenna forming member comprising a plurality of hinged panels over which the received or transmitted wave phase control means are distributed, it includes a plurality of GPS sensors distributed over the panels, enabling measurement and subsequent compensation by the phase-shifters of deformations of the member. At launch, the panels are folded into an elongate cylindrical shell along the launch system axis and having a pyrotechnic trap allowing deployment of the panels. In orbit, this shell constitutes the equipment module integrating all the equipment units other than the panels.

Aguttes; Jean-Paul (Toulouse, FR); Conde; Eric (Aigrefeuille, FR); Sombrin; Jacques (Toulouse, FR)

2001-04-10

283

Mapping chlorophyll- a through in-situ measurements and Terra ASTER satellite data  

Microsoft Academic Search

This paper presents an application of water quality mapping through real-time satellite and ground data. The Lake Beysehir\\u000a which is the largest freshwater lake and drinking water reservoir in Turkey was selected as the study area. Terra ASTER satellite\\u000a image is used as remote sensing data source for water quality mapping in addition to simultaneously performed in-situ measurements.\\u000a Ground data

Bilgehan Nas; Hakan Karabork; Semih Ekercin; Ali Berktay

2009-01-01

284

Ensuring a reliable satellite  

NASA Astrophysics Data System (ADS)

Comprehensive testing and monitoring approaches have been formulated and implemented for Intelsat VI, which is the largest commercial satellite in service. An account is given of the ground test program from unit level through launch site activities, giving attention to the test data handling system. Test methods unique to Intelsat VI encompass near-field anechoic chamber antenna measurements, offloading 1-g deployment of solar cell and deflector antennas, and electrostatic discharge measurements. The problems accruing to the sheer size of this spacecraft are stressed.

Johnson, Charles E.; Persinger, Randy R.; Lemon, James J.; Volkert, Keith J.

285

Radars for the Detection and Tracking of Ballistic Missiles, Satellites, and Planets  

Microsoft Academic Search

? This article is an overview of the forty-plus years in which Lincoln Laboratory has been developing and applying radar techniques for the long- range detection and tracking of ballistic missiles, satellites, and planets. This effort has included the development and use of several large radar systems: the AN\\/FPS-17 radar in Turkey, the Millstone and Haystack radars in Massachusetts, and

Melvin L. Stone; Gerald P. Banner

2000-01-01

286

British American Tobacco's failure in Turkey  

PubMed Central

Background and objectives Transnational tobacco companies (TTCs) considered Turkey an important, potential investment market because of its high consumption rates and domestic commitment to tobacco. This paper outlines how British American Tobacco (BAT) attempted to establish a joint venture with the government monopoly TEKEL, while waiting for privatisation and a private tender. Methods Analysis of tobacco industry documents from the Guildford Depository and online tobacco document sources. Results BAT failed to establish a market share in Turkey until 2000 despite repeated attempts to form a joint venture with Turkey’s tobacco monopoly, TEKEL, once the market liberalised in the mid 1980s. Conclusions BAT’s failure in the Turkish market was due to a misguided investment strategy focused solely on acquiring TEKEL and is contrasted with Philip Morris success in Turkey despite both TTCs working within Turkey’s unstable and corrupt investing climate.

Lawrence, S

2009-01-01

287

Turkey vulture surveys in Cuba  

USGS Publications Warehouse

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.

Wotzkow, C.; Wiley, J.W.

1988-01-01

288

Barriers to Socialization: Turkey and Regional International Organizations  

Microsoft Academic Search

Turkey has long been a productive member of regional international organizations (IOs) like the North Atlantic Treaty Organization and the Council of Europe. Theorists of socialization would predict that Turkey’s activities within these organizations would encourage European Union (EU) members who belong to these IOs to support Turkey’s application for EU membership. In reality, many EU members who share memberships

John A. Scherpereel; Matthew C. Zierler

2011-01-01

289

Feasibility of microminiature satellites  

NASA Astrophysics Data System (ADS)

A conceptual study is conducted on technical problems and system design techniques to accomplish higher performance microminiature satellites by smaller systems. Applications of microminiature satellite technology to practical satellite mission are mentioned. Concepts of microminiature satellites, measures to miniaturize satellites, and micro-miniaturization technologies for communication and data processing, electric solar power paddle, attitude and orbit control, structure, thermal control, propulsion, and instrumentation systems are outlined. Examples of miniaturizing satellite missions such as planet exploration, low-altitude communication networks, space positioning system, low-altitude earth observation mission, clustered satellites, tethered satellites, and timely observation are described. Satellite miniaturizing technology can also be used to launch systems by lasers, and superconductive linear catapults (space escalator). It is pointed out that keys to promote satellite miniaturization are electronics, precision machining, raw material, electric power source technologies, and system design technology to integrate those technologies.

Imai, Ryouichi

1991-07-01

290

Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey  

Microsoft Academic Search

This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements\\u000a for monitoring the changes in structural plant diversity in Yaln?zçam Scots pine forest in NE Turkey from 1972 to 2005. The\\u000a successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS),\\u000a aerial photos and high resolution satellite

Salih Terzio?lu; Emin Zeki Ba?kent; Ali ?hsan Kad?o?ullar?

2009-01-01

291

Outer planet satellites  

SciTech Connect

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.

Schenk, P.M. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

292

Suicide in Batman, Southeastern Turkey  

ERIC Educational Resources Information Center

The southeastern part of Turkey has comparatively high female suicide rates. We aimed to research social, economic, cultural, and psychiatric reasons of suicides in Batman in a case-controlled psychological autopsy study comparing suicides with matched community controls. The female suicide rate was 9.3 per 100.000 and the female/male ratio was…

Altindag, Abdurrahman; Ozkan, Mustafa; Oto, Remzi

2005-01-01

293

Adolescent Reproductive Behaviour in Turkey  

Microsoft Academic Search

This study aims at providing information on various aspects of adolescent fertility in Turkey. Data collected from women aged 15-19 in the 1998 Turkish Demographic and Health Survey was used with the aim of 1) identifying levels, patterns, and determinants of adolescent fertility, 2) identifying individual, cultural, and contextual characteristics of adolescent fertility, and 3) providing policy recommendations on adolescent

Turgay ÜNALAN

294

Suicide in Batman, Southeastern Turkey  

ERIC Educational Resources Information Center

|The southeastern part of Turkey has comparatively high female suicide rates. We aimed to research social, economic, cultural, and psychiatric reasons of suicides in Batman in a case-controlled psychological autopsy study comparing suicides with matched community controls. The female suicide rate was 9.3 per 100.000 and the female/male ratio was…

Altindag, Abdurrahman; Ozkan, Mustafa; Oto, Remzi

2005-01-01

295

URBAN GROUNDWATER POLLUTION IN TURKEY  

Microsoft Academic Search

Groundwater pollution in Turkey is examined. Important natural sources of groundwater pollution identified include seawater intrusion, discharges from contaminated lakes and streams, geothermal waters, and dissolution of minerals. The major sources of anthropogenic groundwater contamination identified are: agricultural pesticides and fertilizers; mining waste products; industrial waste; on?site septic tank systems; and pollution from poorly constructed wells. Although industrial waste and

Alper Baba; Onder Ayyildiz

296

Biomass energy potential in Turkey  

Microsoft Academic Search

Biomass energy includes fuelwood, agricultural residues, animal wastes, charcoal and other fuels derived from biological sources. It currently accounts for about 14% of world energy consumption. Biomass is the main source of energy for many developed and developing countries. In Turkey energy wood is available in the form of forest chips, fuelwood, wood waste, wood pellets, and it is also

K. Kaygusuz; M. F. Türker

2002-01-01

297

The role of rain in satellite communications  

Microsoft Academic Search

The most fundamental obstacle encountered in design of satellite communication systems at frequencies above 10 GHz is attenuation by rain. The microwave power radiated toward an earth station, being limited by factors such as available primary power and size of antenna on the satellite, is insufficient, with present technology, to overcome the large attenuation produced by intense rain cells on

D. C. Hogg; Ta-Shing Chu

1975-01-01

298

Mobile internet access using satellite networks  

Microsoft Academic Search

SUMMARY Satellites offer a promising alternative for mobile access to the Internet by both pedestrians, and more importantly, from vehicles. As such, satellites provide an essential complement to the cellular radio (UMTS) infrastructure in sparsely populated areas where high bandwidth UMTS cells cannot be economically deployed. In this paper, we analyse various mobile Internet applications in representative urban scenarios for

P. Loreti; M. Luglio; R. Kapoor; J. Stepanek; M. Gerlak; F. Vatalaro; M. A. Vazquez-Castro

2004-01-01

299

Civil Society in Turkey and Local Dimensions of Europeanization  

Microsoft Academic Search

Since the Helsinki Summit of 1999 when Turkey’s candidacy for membership was accepted, the EU has exercised considerable transformative power over the development of Turkey’s civil society. This article examines Turkish civil society both as an agent of the ‘internationalization’ of domestic social agendas and as a reflection of more general Turkish perceptions of the EU and Turkey’s prospective membership.

Ayça Ergun

2010-01-01

300

The Soviet navigation satellites  

NASA Astrophysics Data System (ADS)

The list of the satellites officially recognized as navigation satellites is drawn up, together with the much longer list of the satellites which might be recognized as such. A survey is made of the clues which enable to corroborate or contradict the presumed navigation mission of those satellites. The development of the navigation satellites programmed is reconstructed and some details on the two big classes of navigation satellites put into circular orbits at altitudes of around 1000 and 19,000 kilometers are given.

Laurent, D.

301

Centromere detection in vinblastine- and radiation-induced micronuclei of cytokinesis-blocked mouse cells by using in situ hybridization with a mouse gamma (major) satellite DNA probe  

SciTech Connect

Non-isotopic in situ hybridization using a mouse gamma (major) satellite probe DNA was applied to detect centromeres in micronuclei, which were induced in vitro mouse liver cells by ionizing radiation and by vinblastine sulfate. In a cytokinesis-blocked micronucleus assay a dose-dependent induction of micronuclei was found for both agents. After vinblastine exposure the observed micronuclei showed centromere-positive hybridization signals in an order of magnitude of 70-91%, but after radiation exposure the magnitude was only 10-20%. Since the in situ hybridization technique detects centromeric DNA directly, it can be used in a cytokinesis-blocked micronucleus assay for a rapid and reliable discrimination between aneuploidy-inducing and clastogenic agents.

Salassidis, K.; Huber, R.; Zitzelsberger, H.; Bauchinger, M. (Inst. fuer Strahlenbiologie, Neuherberg (West Germany))

1992-01-01

302

Satellite Imaging Corporation: IKONOS Satellite Images  

NSDL National Science Digital Library

Satellite Imaging Corporation (SIC) acquires and processes imagery from the IKONOS satellite as well as others and makes the products available through their website. The images in the gallery are arranged in several categories based on what applications the images might be useful for, such as Agriculture, Coastal Management, or Sports and Tourism.

Corporation, Satellite I.

303

Municipal solid waste management strategies in Turkey.  

PubMed

Municipal solid waste (MSW) is a major environmental problem in Turkey, as in many developing countries. Problems associated with municipal solid waste are difficult to address, but efforts towards more efficient collection and transportation and environmentally acceptable waste disposal continue in Turkey. Although strict regulations on the management of solid waste are in place, primitive disposal methods such as open dumping and discharge into surface water have been used in various parts of Turkey. This study presents a brief history of the legislative trends in Turkey for MSW management. The study also presents the MSW responsibility and management structure together with the present situation of generation, composition, recycling, and treatment. The results show that approximately 25 million ton of MSW are generated annually in Turkey. About 77% of the population receives MSW services. In spite of efforts to change open dumping areas into sanitary landfills and to build modern recycling and composting facilities, Turkey still has over 2000 open dumps. PMID:18644708

Turan, N Gamze; Coruh, Semra; Akdemir, Andaç; Ergun, Osman Nuri

2008-07-21

304

Humoral and Cellular Immune Responses in Turkey Poults Infected with Turkey Coronavirus  

Microsoft Academic Search

The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavi- rus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different

C. C. Loa; T. L. Lin; C. C. Wu; T. Bryan; H. L. Thacker; T. Hooper; D. Schrader

2001-01-01

305

Specific mucosal IgA immunity in turkey poults infected with turkey coronavirus  

Microsoft Academic Search

The objective of this study was to elucidate the kinetics and magnitudes of specific IgA antibody responses in intestines of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 days of age. Intestinal segment cultures were administered for duodenum, jejunum, and ileum and the IgA antibody responses were analyzed at 1, 2, 3,

C. C Loa; T. L Lin; C. C Wu; T Bryan; T Hooper; D Schrader

2002-01-01

306

Satellite RNAs and Satellite Viruses of Plants  

PubMed Central

The view that satellite RNAs (satRNAs) and satellite viruses are purely molecular parasites of their cognate helper viruses has changed. The molecular mechanisms underlying the synergistic and/or antagonistic interactions among satRNAs/satellite viruses, helper viruses, and host plants are beginning to be comprehended. This review aims to summarize the recent achievements in basic and practical research, with special emphasis on the involvement of RNA silencing mechanisms in the pathogenicity, population dynamics, and, possibly, the origin(s) of these subviral agents. With further research following current trends, the comprehensive understanding of satRNAs and satellite viruses could lead to new insights into the trilateral interactions among host plants, viruses, and satellites.

Hu, Chung-Chi; Hsu, Yau-Heiu; Lin, Na-Sheng

2009-01-01

307

Satellite broadcasting in Europe  

NASA Astrophysics Data System (ADS)

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.

Bartholome, P.

1984-05-01

308

Aeronautical Mobile Satellite Experiment.  

National Technical Information Service (NTIS)

The various activities and findings of a NASA/FAA/COMSAT/INMARSAT collaborative aeronautical mobile satellite experiment are detailed. The primary objective of the experiment was to demonstrate and evaluate an advanced digital mobile satellite terminal de...

T. C. Jedrey K. I. Dessouky N. E. Lay

1990-01-01

309

Random Communication Satellite Coverage.  

National Technical Information Service (NTIS)

The report develops models for assessing credible satellite failure rates, population densities, coverage probabilities, and outage intervals. These models are interpreted in terms of the present random military communication satellite system. A sufficien...

C. S. Lorens

1967-01-01

310

Hurricane Katrina Satellite Imagery  

NSDL National Science Digital Library

This page provides access to a good number of satellite images of Hurricane Katrina taken by polar orbiting and geostationary satellites operated by NOAA. High resolution images are available on the site.

National Environmental Satellite, Data, and Information Service

311

The Kosmos Satellites.  

National Technical Information Service (NTIS)

The general principles and tasks of the 'Kosmos' satellites series were discussed. The operating principles of these satellites, the make-up of the service and scientific apparatus installed on them, and the most important scientific results obtained with...

Y. I. Zaytsev

1975-01-01

312

The Mexican national satellite system  

NASA Astrophysics Data System (ADS)

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.

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

1983-10-01

313

TubeSpin satellites: a fast track approach for process development with animal cells using shaking technology  

Microsoft Academic Search

Process development with mammalian cells is often limited by the lack of resources and assay capacity to deal with the multiplicity and complexity of interrelated parameters in culture technology. Multi-component analysis, an issue in media development and in screening of newly established production cell lines, is subject to the same limitations. We therefore developed a high throughput system for the

Maria J De Jesus; Philippe Girard; Michaela Bourgeois; Gwendoline Baumgartner; Barbara Jacko; Hanspeter Amstutz; Florian M Wurm

2004-01-01

314

Modern Technologies: Satellites  

NSDL National Science Digital Library

The world's increasing dependence on satellites was recently made clear when a PanAmSat communications satellite went down, disrupting communication and data transmission around the world. The eight resources in this week's In the News highlight satellites, and the many important roles they play in our lives. Today, satellites are used to convey a wealth of information, from communications to important scientific data.

Harris, Kathryn L.

1998-01-01

315

Earth System: Satellites  

NSDL National Science Digital Library

There are thousands of artificial satellites circling our planet for navigation, communications, entertainment, and science. These satellites are an integral part of our everyday life, and they collect data which cannot be obtained from Earth's surface. This video segment describes the basic components of a satellite and some of applications that have been developed for both geostationary and orbiting satellites. The segment is three minutes fifty seconds in length. A background essay and discussion questions are included.

316

Geosynchronous satellites for MUOS  

Microsoft Academic Search

This paper proposes satellites in geosynchronous Earth orbit (GEO) for the mobile user objective system (MUOS). Each satellite has a large, deployable, multibeam antenna and onboard signal processing. The high directivity of the antenna enables small disadvantaged terminals with severe propagation impairments to reliably communicate via satellite and permits substantial frequency reuse. The design incorporates efficient access control, modulation, and

Samuel J. MacMullan; Christopher J. Karpinsky; Reuben E. Eaves; Andre R. Dion

1999-01-01

317

Satellite broadcasting in Europe  

Microsoft Academic Search

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

P. Bartholome

1984-01-01

318

Geostationary Satellite Server  

NSDL National Science Digital Library

This database contains imagery from geosationary satellites. Visitors can access daily images or archived imagery form GOES-9, METEOSAT, and other satellites. The imagery features hemispheric and whole-disk views of Earth, water vapor maps, and images of storms and other special events. Links to satellite homepages and to other related topics are included.

319

Digital communications by satellite  

Microsoft Academic Search

Topics in digital satellite communications are treated extensively for a readership of students or communications system designers acquainted with communications theory fundamentals and random processes. Major parts of the book are: signal quantizing and multiplexing; satellite communications; modulation and coding in distorted channels; worldwide timing by satellite relay. Some specific topics treated include: PCM quantizing, sampling of nonbandlimited signals, delta

J. J. Spilker Jr.

1977-01-01

320

The Agricultural Satellite Corporation  

Microsoft Academic Search

The Agricultural satellite Corporation (AG*SAT) is a consortium of 43 land-grant universities and two agencies of the USDA joined together to produce and share educational programming via satellite, computer, and other technologies. Sparked by the opportunity to receive Federal funding for satellite receive and transmit facilities, the institutions have invested financial and personnal resources in the purchase and installation of

Randall G. Bretz

1993-01-01

321

Health services pricing in Turkey.  

PubMed

One of the most important and complex decisions that public services managers have to make is pricing. This is especially difficult within public health care because pricing decisions are influenced by a myriad of ideological, political, economic and professional arguments. In Turkey the majority of health care services are provided under public auspice; however, recent changes in governmental policy have led to increased competition among hospitals in both the public and private sector. Therefore, all institutions are being watched and remain open to government scrutiny and regulation. The aim of the study is to analyze how the private and governmental hospitals determine pricing or the actual cost of services in Turkey. Also, comparisons are made between health services expenditures and the Consumer Price Index with suggestions provided for public and private hospital managers in regard to the general cost of health services. PMID:11183658

Tengilimoglu, D; Dziegielewski, S F

2000-01-01

322

Turkey: World Oil Report 1991  

SciTech Connect

This paper reports on a marked oil production increase, an exploration program in the Black Sea and the planned development of an offshore gas field in the Sea of Mamara in Turkey. The production increase stems from development of new fields in southeastern Turkey by Turkiye Petrolleri Anonim Ortakligi (TPAO), the national oil company. Discovered in 1989, development of Kahta, Karakus, Cendere and several other nearby finds have pushed Turkish crude output to the highest level in 14 years. Last May, BP entered into a three-year joint venture with TPAO to explore a 29,344 sq mi area in the Black Sea in waters to 6,500+ ft deep. The three-year program calls for BP to run seismic this year followed by its Airborne Laser Fluorosensor survey technique. Drilling will depend on survey results.

Not Available

1991-08-01

323

The Genome of Turkey Herpesvirus  

Microsoft Academic Search

Here we present the first complete genomic sequence of Marek's disease virus serotype 3 (MDV3), also known as turkey herpesvirus (HVT). The 159,160-bp genome encodes an estimated 99 putative proteins and resembles alphaherpesviruses in genomic organization and gene content. HVT is very similar to MDV1 and MDV2 within the unique long (UL) and unique short (US) genomic regions, where homologous

C. L. Afonso; E. R. Tulman; Z. Lu; L. Zsak; D. L. Rock; G. F. Kutish

2001-01-01

324

[Effect of low-intensity magnetic fields on the development of satellite muscle cells of a newborn rat in the primary culture].  

PubMed

The influence of Earth magnetic field shielded down to 0.3 microT and static magnetic field (60-160 microT) on the proliferation and differentiation of satellite muscle cells in the primary culture has been investigated. A stimulatory effect of static magnetic fields on the rate of the formation of massive multinucleated myotubes and an increase in the intracellular calcium concentration ([Ca2+]i) have been detected for magnetic fields of the microtesla range. On the other hand, it was shown that the reduction of earth magnetic fields to 0.3 microT leads to the inhibition of proliferation and differentiation of skeletal muscle cells in the primary culture. Since the formation of contractile myotubes during in vitro experiments is similar to the regeneration of skeletal muscle fibers under muscle damage in vivo, it may be concluded that weak magnetic fields have a strong effect on intracellular processes by influencing all phases of muscle fiber formation. It is necessary to take this fact into consideration when forecasting probable complications of skeletal muscle regeneration during long-term exposure of man to low-intensity magnetic fields and also for the potential use of low static magnetic fields as a tool to recover the affected myogenesis. PMID:21033354

Eldashev, I S; Shchegolev, B F; Surma, S V; Belostotskaia, G B

325

Vaccination of young turkeys against fowl cholera  

Microsoft Academic Search

Turkey poults vaccinated at one day of age with commercial inactivated Pasteurella multocida (PM) bacterin responded with low titres of antibody (ab) as measured by ELISA, but had an acceptable degree of resistance when challenged with the X?73 strain of PM until 13 weeks of age. Turkeys vaccinated at 3 and\\/or 6 weeks of age responded with higher ab titres

B. Perelman; D. Hadash; M. Meroz; M. Abramson; Y. Samberg

1990-01-01

326

On the wind energy in Turkey  

Microsoft Academic Search

Increase in negative effects of fossil fuels on the environment has forced many countries, including Turkey, to use renewable energy sources. Today, clean, domestic and renewable energy is commonly accepted as the key for future life, not only for Turkey but also for the world. As wind energy is an alternative clean energy source compared to the fossil fuels that

Erkan Erdogdu

2009-01-01

327

Turkey's Oil and Natural Gas Pipelines System  

Microsoft Academic Search

Turkey's natural gas (NG) production is very small and is almost all imported. Turkish natural gas production in 2000, 23 billion cubic feet (Bcf), met around 4% of domestic natural gas consumption requirements. NG consumption is estimated at around 700 Bcf in year 2002, accounting for around 17% of Turkey's total energy consumption. Turkish natural gas demand had been projected

Mustafa Balat; Nuray Ozdemir

2005-01-01

328

Current Regulatory Earthquake Zoning Map of Turkey  

Microsoft Academic Search

Preparation of latest version of the regulatory earthquake zoning map of Turkey, which was one of the activities in the National Plan of Turkey for International Decade for Natural Disaster Reduction (IDNDR) period (1990-2000), was achieved by Earthquake Research Department at General Directorate of Disaster Affairs in cooperation with Earthquake Engineering Research Center at Middle East Technical University. Different from

Nazan Yilmaz; Murat Nurlu; Bekir Tüzel

329

Rights of the Child in Turkey.  

ERIC Educational Resources Information Center

|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…

Naqvi, Yasmin

330

The state of media literacy in Turkey  

Microsoft Academic Search

Critical media literacy embodies the issues of participation and critical analysis. Unlike many countries, media literacy education in Turkey has emerged as a state effort rather than a local grassroots movement. This study provides a discursive analysis of ‘media literacy’ as represented on the official web site of the project. We argue that media literacy efforts in Turkey follow “a

Özlem Oguzhan; Nazan Haydari

2011-01-01

331

Prevalence of parvoviruses in commercial turkey flocks.  

PubMed

Turkey parvovirus belongs to the family Parvoviridae, subfamily Parvovirinae, Genus parvovirus. Since the initial report on turkey parvovirus in the United States appeared in 1983, there had been no further reports of parvovirus in turkeys until 2008. The aims of our study were to determine the prevalence of parvovirus in commercial turkey flocks using PCR; to determine their genetic relationship to previous strains identified in North America and Europe; and to test samples for enteric viruses by transmission electron microscopy (TEM). A total of 169 fecal samples collected from 42 turkey farms in four different states within the United States between 2000 and 2010 were examined. We found that the most frequently detected viruses by TEM were small round viruses, accounting for 52% of the examined samples; however, the PCR detected parvoviruses in 71% of the samples. The phylogenetic analysis of partial nonstructural gene sequences showed a certain degree of variability among the turkey samples tested in the study. Moreover, there was a clear dichotomy in the phylogenetic tree between chicken and turkey samples, with the exception of one turkey isolate from 2000, which clustered together with the chicken group. PMID:23397849

Murgia, M V; Rauf, A; Tang, Y; Gingerich, E; Lee, C-W; Saif, Y M

2012-12-01

332

New Records of Aphid Fauna in Turkey  

PubMed Central

Three aphid species were identified as new records for Turkey aphid fauna from Bartin province. These species are Ceruraphis viburnicola (Gillette) (Hemiptera: Aphididae), Dysaphis apiifolia (Theobald) (Hemiptera: Aphididae) and Macrosiphum mordvilkoi Miyazaki (Hemiptera: Aphididae). These records increase the recorded aphid-fauna of Turkey to 433 species.

Kaygin, Azize Toper; Gorur, Gazi; Cota, Figen

2010-01-01

333

Turkey's national security in the Middle East  

Microsoft Academic Search

The Middle East poses threats and opportunities for Turkey's national security. This article analyzes Turkey's national security considering five integrated variables: the regime's political legitimacy, the society's ethnic and religious tolerance, the availability of essential natural resources such as water, oil, and gas, the state's economic capabilities, and the state's military capabilities. The article examines the foreign policy directions and

Lenore Martin

2000-01-01

334

Attenuation modeling of recent earthquakes in Turkey  

Microsoft Academic Search

This paper deals with the derivation of a consistent set of empiricalattenuation relationships for predicting free-field horizontal components ofpeak ground acceleration (PGA) and 5 percent damped pseudoacceleration response spectra (PSA) from 47 strong ground motion recordsrecorded in Turkey. The relationships for Turkey were derived in similarform to those previously developed by Boore et al. (1997) for shallowearthquakes in western North

Polat Gülkan; Erol Kalkan

2002-01-01

335

Attenuation modeling of recent earthquakes in Turkey  

Microsoft Academic Search

This paper deals with the derivation of a consistent set of empirical attenuation relationships for predicting free-field horizontal components of peak ground acceleration (PGA) and 5 percent damped pseudo acceleration response spectra (PSA) from 47 strong ground motion records recorded in Turkey. The relationships for Turkey were derived in similar form to those previously developed by Boore et al. (1997)

Polat Gülkan; Erol Kalkan

2002-01-01

336

Suspended sediment yields of rivers in Turkey  

Microsoft Academic Search

The aim of this paper is to quantify the spatial distribution of suspended sediment yields of rivers in Turkey, and to quantify the suspended sediment flux to the sea, to lakes and reservoirs, and out of the country. Sediment yields in Turkey vary in accordance with the erosion potential of the river basins and values range from 12 to 609

FAZLI OZTURK

337

Turkey Hatchery. (Released January 15, 2013).  

National Technical Information Service (NTIS)

Turkey eggs in incubators on January 1, 2013, in the United States totaled 28.1 million, down 1 percent from January 1, 2012. Eggs in incubators were up 5 percent from the December 1, 2012 total of 26.7 million eggs. Turkey poults hatched during December ...

2013-01-01

338

Primary Education Curriculum Reforms in Turkey  

ERIC Educational Resources Information Center

|The aim of this study is to examine and evaluate the basic structure of changes in primary educational curricula in Turkey since the establishment of Republic. The study is mainly qualitative and is based on literature and document analyses and teaching curricular reviews. The research findings indicate that primary educational reforms in Turkey

Akinoglu, Orhan

2008-01-01

339

WOMEN MANAGERS IN PRINTED MEDIA AND TURKEY  

Microsoft Academic Search

In this study, we first offer the recent statistics about the women workforce and women managers in Turkey. Then we focus on the major factors that deprive many working women of the managerial positions and consider the problems that the women managers face in companies. Finally the news texts, including the female managers in the mass media of Turkey will

Senem Besler; Ilke Oruc

2010-01-01

340

Turkeys Raised (Released August 25, 2000).  

National Technical Information Service (NTIS)

The preliminary estimate of turkeys raised in the United States during 2000 is 273 million, the same as were raised during 1999. The following six States are expected to account for about two-thirds of the turkeys produced in the United States during 2000...

2000-01-01

341

Turkeys Raised (Released August 23, 2002).  

National Technical Information Service (NTIS)

The preliminary estimate of turkeys raised in the United States during 2002 is 270 million, down 1 percent from the number raised during 2001. The following six States are expected to account for about two-thirds of the turkeys produced in the United Stat...

2002-01-01

342

Turkeys Raised (Released August 24, 2001).  

National Technical Information Service (NTIS)

The preliminary estimate of turkeys raised in the United States during 2001 is 270 million, the same as were raised during 2000. The following six States are expected to account for about two-thirds of the turkeys produced in the United States during 2001...

2001-01-01

343

Rise of Political Islam in Turkey.  

National Technical Information Service (NTIS)

As a Muslim-majority country that is also a secular democratic state, a member of NATO, and a long-standing U.S. ally, Turkey is pivotal to U.S. strategy to shape the Middle Eastern security environment. Turkey also is a key test case for the role of Isla...

A. Rabasa F. S. Larrabee

2008-01-01

344

Dental remains of fossil elephants from Turkey  

Microsoft Academic Search

Turkey is at the crossroads of Africa, Asia and Europe, and occupies an important position for the migration of mammals such as elephantids. Nonetheless, there has been no detailed study of fossil elephants from Turkey. In this study, elephant remains from five localities were examined. Mammuthus meridionalis, Mammuthus trogontherii, Elephas maximus and probably Palaeoloxodon antiquus were identified. M. meridionalis remains from

Ebru Albayrak; Adrian M. Lister

345

Citizenship Education in Turkey: Inclusive or Exclusive  

ERIC Educational Resources Information Center

|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…

Ince, Basak

2012-01-01

346

Government Publications and Gray Literature in Turkey  

ERIC Educational Resources Information Center

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…

Anameric, Hakan

2009-01-01

347

PREVALENCE OF ARCOBACTER IN COMMERCIAL TURKEY PRODUCTION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Many protocols have been developed to determine the incidence of Arcobacter in livestock and their products, none of which are clearly defined for use in turkeys. Six Midwestern commercial turkey farms were selected for sampling in 2003 to determine the best protocol for the isolation as well as to...

348

Government Publications and Gray Literature in Turkey  

ERIC Educational Resources Information Center

|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…

Anameric, Hakan

2009-01-01

349

Rights of the Child in Turkey.  

ERIC Educational Resources Information Center

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…

Naqvi, Yasmin

350

Solar drying in sludge management in Turkey  

Microsoft Academic Search

Two main wastewater treatment plants in Bursa city in Turkey will start to operate and produce at least 27,000 tons of dry solids per year by the end of 2006. The purpose of this study was to investigate an economical solution to the sludge management problem that Bursa city would encounter. The general trend in Turkey is mechanical dewatering to

Nezih Kamil Salihoglu; Vedat Pinarli; Guray Salihoglu

2007-01-01

351

Importance of biomass energy sources for Turkey  

Microsoft Academic Search

Various agricultural residues such as grain dust, crop residues and fruit tree residues are available in Turkey as the sources of biomass energy. Among the biomass energy sources, fuelwood seems to be one of the most interesting because its share of the total energy production of Turkey is high at 21% and the techniques for converting it to useful energy

Ayhan Demirbas

2008-01-01

352

Cool Turkey: Solving the Image Problem to Secure EU Membership  

Microsoft Academic Search

According to the autumn 2005 Eurobarometer 55 per cent of the EU population perceive Turkey to be culturally too different to fit into the EU. Given that Turkey's accession to the EU will require ratification by the member states, this perception poses a problem for Turkey. This article discusses whether and how Turkey can solve its image problem. It argues

Rainer Hülsse

2006-01-01

353

Building technological capability within satellite programs in developing countries  

NASA Astrophysics Data System (ADS)

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 outside the space arena in which organizations have pursued technological capability. Scholars have analyzed these examples and developed insightful frameworks. The paper draws key concepts from this literature about the nature of development, technology, knowledge and organizational learning. These concepts are relevant to learning in new satellite programs, but the ideas must be applied cautiously because of the nature of satellite technology. The paper draws three major lessons from the international development literature regarding absorptive capacity, tacit knowledge and organizational learning; it synthesizes these lessons into a cohesive, original framework. The closing section proposes future work on a detailed study of technological learning in specific government satellite programs.

Wood, Danielle; Weigel, Annalisa

2011-12-01

354

Spectrally resolved DNI measurements: Results of a field comparison of spectroradiometers, component cells and the SOLIS satellite model  

NASA Astrophysics Data System (ADS)

One remote sensing and two in-situ methods for quantifying the spectral distribution of the direct normal irradiance and its impact on multi-junction solar cells are compared for three different sites in Southern Europe, on the Arabian Peninsula and in the South West of the USA. For each method, the uncertainty is assessed. The spectral parameter Z is used to quantify the differences between the methods.

Gerstmaier, Tobias; van Riesen, Sascha; Schulz-Gericke, Jan; Gombert, Andreas; Behrendt, Tanja; Lorenz, Elke; Steiner, Marc; Schachtner, Michael; Siefer, Gerald; Bett, Andreas W.

2012-10-01

355

Acute morphine activates satellite glial cells and up-regulates IL-1? in dorsal root ganglia in mice via matrix metalloprotease-9  

PubMed Central

Background Activation of spinal cord glial cells such as microglia and astrocytes has been shown to regulate chronic opioid-induced antinociceptive tolerance and hyperalgesia, due to spinal up-regulation of the proinflammatory cytokines such as interleukin-1 beta (IL-1?). Matrix metalloprotease-9 (MMP-9) has been implicated in IL-1? activation in neuropathic pain. However, it is unclear whether acute opioid treatment can activate glial cells in the peripheral nervous system. We examined acute morphine-induced activation of satellite glial cells (SGCs) and up-regulation of IL-1? in dorsal root ganglia (DRGs), and further investigated the involvement of MMP-9 in these opioid-induced peripheral changes. Results Subcutaneous morphine injection (10 mg/kg) induced robust peripheral glial responses, as evidenced by increased GFAP expression in DRGs but not in spinal cords. The acute morphine-induced GFAP expression is transient, peaking at 2 h and declining after 3 h. Acute morphine treatment also increased IL-1? immunoreactivity in SGCs and IL-1? activation in DRGs. MMP-9 and GFAP are expressed in DRG neurons and SGCs, respectively. Confocal analysis revealed a close proximity of MMP-9 and GFAP immunostaining. Importantly, morphine-induced DRG up-regulation of GFAP expression and IL-1? activation was abolished after Mmp9 deletion or naloxone pre-treatment. Finally, intrathecal injections of IL-1?-selective siRNA not only reduced DRG IL-1? expression but also prolonged acute morphine-induced analgesia. Conclusions Acute morphine induces opioid receptors- and MMP-9-dependent up-regulation of GFAP expression and IL-1? activation in SGCs of DRGs. MMP-9 could mask and shorten morphine analgesia via peripheral neuron-glial interactions. Targeting peripheral glial activation might prolong acute opioid analgesia.

2012-01-01

356

World atlas of satellites  

NASA Astrophysics Data System (ADS)

Features of the 17 services offered by planned or operational satellites in geostationary earth orbit (GEO) are described. The orbital inclinations, controlling organizations, and frequency bands employed by the 143 spacecraft in GEO as of 1979 are provided, together with the typical operational parameters of the 6/4 GHz transmitters and receivers. The spacecraft have nominal design lifetimes of 10-15 yr and employ FDM-FM, digital, SCPC, and video transmission techniques. Attention is given to the technology developments affecting GEO satellite system characteristics and the capacity of the GEO. Intersatellite service is characterized, as are frequency allocations and applications, and the space operation service involving frequency bands dedicated to the telemetry, tracking, and telecommand of spacecraft. Consideration is given to mobile satellite services, satellite broadcasting services, and satellite navigation, earth exploration, and positioning services. Finally, meteorological, standard frequency and time signal, and space research satellite services are explored, noting that the latter do not usually use GEO positions.

Jansky, D. M.

357

Communication satellite applications  

NASA Astrophysics Data System (ADS)

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.

Pelton, Joseph N.

358

Satellite glial cell P2Y12 receptor in the trigeminal ganglion is involved in lingual neuropathic pain mechanisms in rats  

PubMed Central

Background It has been reported that the P2Y12 receptor (P2Y12R) is involved in satellite glial cells (SGCs) activation, indicating that P2Y12R expressed in SGCs may play functional roles in orofacial neuropathic pain mechanisms. However, the involvement of P2Y12R in orofacial neuropathic pain mechanisms is still unknown. We therefore studied the reflex to noxious mechanical or heat stimulation of the tongue, P2Y12R and glial fibrillary acidic protein (GFAP) immunohistochemistries in the trigeminal ganglion (TG) in a rat model of unilateral lingual nerve crush (LNC) to evaluate role of P2Y12R in SGC in lingual neuropathic pain. Results The head-withdrawal reflex thresholds to mechanical and heat stimulation of the lateral tongue were significantly decreased in LNC-rats compared to sham-rats. These nocifensive effects were apparent on day 1 after LNC and lasted for 17 days. On days 3, 9, 15 and 21 after LNC, the mean relative number of TG neurons encircled with GFAP-immunoreactive (IR) cells significantly increased in the ophthalmic, maxillary and mandibular branch regions of TG. On day 3 after LNC, P2Y12R expression occurred in GFAP-IR cells but not neuronal nuclei (NeuN)-IR cells (i.e. neurons) in TG. After 3 days of successive administration of the P2Y12R antagonist MRS2395 into TG in LNC-rats, the mean relative number of TG neurons encircled with GFAP-IR cells was significantly decreased coincident with a significant reversal of the lowered head-withdrawal reflex thresholds to mechanical and heat stimulation of the tongue compared to vehicle-injected rats. Furthermore, after 3 days of successive administration of the P2YR agonist 2-MeSADP into the TG in naïve rats, the mean relative number of TG neurons encircled with GFAP-IR cells was significantly increased and head-withdrawal reflex thresholds to mechanical and heat stimulation of the tongue were significantly decreased in a dose-dependent manner compared to vehicle-injected rats. Conclusions The present findings provide the first evidence that the activation of P2Y12R in SGCs of TG following lingual nerve injury is involved in the enhancement of TG neuron activity and nocifensive reflex behavior, resulting in neuropathic pain in the tongue.

2012-01-01

359

Satellite multiple access protocols  

Microsoft Academic Search

Each one of the independent transponders in the satellite is designed to accept transmission at a selected frequency band, i.e., the uplink frequency. The satellite carries out a frequency translation to a well-defined frequency band, i.e., the downlink frequency. This scheme thus divides the total bandwidth of the satellite into well-defined channels. The advantages provided by this scheme are reduced

C. Retnadhas

1980-01-01

360

Satellites Orbiting Earth  

NSDL National Science Digital Library

In recent years, there has been a push to better understand how Earth works as a system- how land, oceans, air, and life all interact. Satellites in orbit around Earth are a fast and efficient way of gathering remotely sensed data about the planet as a whole. This animated video shows the orbital paths of the satellites in the National Aeronautics and Space Administration (NASA) Earth Observing System (EOS), a collection of satellites that work together to study Earth on a wide scale.

361

Multimedia and children in Turkey.  

PubMed

Multimedia will be regarded as essential tools for children to create their new world. The effects of television on young children's life have been well studied. Television differs, however, from other media, including the movies, in its pervasive impact on children. Children spend more time watching television than any other activity except sleeping. Overall 31% of children spent at least 4 hours a day watching television during weekday and 71.7% during weekend in Turkey. Television's influence on children is a function of the length of time they spend watching and the cumulative effect of what they see. Television may be a cause as well as a solution for many serious childhood problems. Excessive viewing of television has also been linked to aggressive behavior, violence, childhood obesity. On the other hand, television may act as a socializing agent and as a learning tool if the recommendations of American Academy of Pediatrics is learned by pediatricians, parents and broadcasters. The use of home personal computers in urban residence increased from 3.2% in 1993 to 6.5% by January 1998 in Turkey. Around 20% of computer households reported owing a modem. Internet has been using only for 5 years in Turkey. Nearly 40% of computer households also used CD-ROM equipment. The percentage of schools that have a computer laboratory is only 2.64%. On the other hand, multimedia allows students to move away from a uniform education for everyone to assert individual identity, liberalize education and management. It seems likely that, within the next few years, most of the countries with substantial internet infrastructure will use the internet as the major medium for disseminating information, including information on children. To prepare students for such a world demands that educational systems make the best possible use of all knowledge and technologies currently available. PMID:10770073

Tuncer, A M; Yalçin, S S

1999-01-01

362

How Satellites See  

NSDL National Science Digital Library

This lesson allows students to compare and contrast three NASA satellites: The Extreme Ultraviolet Explorer (EUVE), The Cosmic Background Explorer (COBE), and the Hubble Space Telescope (HST). The lesson includes access to data and images from these three NASA astronomy satellites, contrasting the way the sky appears in three very different electromagnetic wavelengths or colors of light. Other satellite information is included, but the focus is a simple introduction to the electromagnetic spectrum as used by the three space observatories. While participating in this activity, students will compare physical parts and orbits of each satellite and participate in hands-on experiments to begin to understand visible, infrared and ultraviolet wavelengths.

363

Direct broadcast satellite receivers  

NASA Astrophysics Data System (ADS)

The feasibility of broadcasting direct to the home from a geostationary satellite was recognized at least two decades ago and by the mid-1960s the receiver industry was already considering the implications. Attention is given to allocations and transmission parameters, broadcast satellite plans, television receiving systems, individual satellite television receiver components, and aspects of sound broadcast reception. It is concluded that satellite television broadcasting services will be introduced by a number of European countries in the next two or three years. The requirement for mass-produced equipment for individual reception of such signals has been shown to be realizable, and development of low-cost solutions is now in progress.

Freeman, K. G.

1982-03-01

364

Isolation and characterization of a turkey arthritis reovirus.  

PubMed

During the spring and summer of 2011, the Minnesota Veterinary Diagnostic Laboratory at the University of Minnesota received 14 submissions of 15-to-18-week-old tom turkeys that were recumbent with wing tip bruises ("wing walkers") and uni- or bilateral swelling of the hock (tibiotarsal) joints. Gastrocnemius or digital flexor tendons were occasionally ruptured. A total of five turkey arthritis reoviruses (TARV-MN1 through TARV-MN5) were isolated in specific-pathogen-free embryonated chicken eggs and QT-35 cells. The identity of the isolates was confirmed by electron microscopy, reverse transcription-polymerase chain reaction, and gene sequence analysis. BLAST analysis on the basis of a 880 bp nucleotide sequence of the S4 gene confirmed all isolates as a reovirus. Phylogenetic analysis divided the five isolates into two subgroups: subgroup I containing TARV-MN1, -2, -3, and -5, and the other subgroup containing TARV-MN4. Isolates in subgroup I had a similarity of 97%-100% with each other, while subgroup II (TARV-MN4) had a similarity of only 89.2% with subgroup I viruses. This isolate showed 90%-93% similarity with turkey enteric reoviruses in the United States, while the other four isolates in subgroup I had 89%-97.6% similarity. These results indicate divergence within TARVs as well as from enteric viruses, which needs to be confirmed by complete genome sequence analysis. Further experimental studies are planned to determine the role of these isolates in turkey arthritis and to compare them with classical chicken reovirus. PMID:23678736

Mor, Sunil K; Sharafeldin, Tamer A; Porter, Robert E; Ziegler, Andre; Patnayak, Devi P; Goyal, Sagar M

2013-03-01

365

Cross-reactive anti-chicken CD4 and CD8 monoclonal antibodies suggest polymorphism of the turkey CD8alpha molecule.  

PubMed

To measure turkey CD4 and CD8 T cell levels, the cross-reactivity of mouse anti-chicken CD4 and CD8 monoclonal antibodies (mAb) with turkey leucocytes was tested by flow cytometric analysis of blood obtained from individuals in five turkey lines. The turkey lines used included a randombred control population (RBC2), a subline (F) of RBC2 selected for increased 16-wk BW, and a sire line (A, B, and C) from each of three commercial turkey breeders. Peripheral blood lymphocytes were isolated and stained with single or dual color staining. The CT8 mAb (anti-chicken CD8alpha) failed to detect the CD8alpha molecule in some turkeys, and there were large line differences in ability to detect the CD8alpha molecule. However, certain anti-chicken CD8alpha mAb (3-298, 3-292, and 11-39) had good cross-reactivity with the turkey CD8alpha molecule. These present data indicate that the turkey CD8alpha molecule is polymorphic. Some anti-chicken CD4 mAb (CT4, 2-6, 2-35, and 7-125) were also cross-reactive with the turkey CD4 molecule. Immunoprecipitation and Western blotting showed that the 3-298 mAb precipitated a 33- to 35-kDa polypeptide from the turkey splenocyte lysate under reducing conditions. The availability of cross-reactive anti-chicken CD4 and CD8 mAb will facilitate the studies of immune responses in turkeys. PMID:10560824

Li, Z; Nestor, K E; Saif, Y M; Fan, Z; Luhtala, M; Vainio, O

1999-11-01

366

FOP is a centriolar satellite protein involved in ciliogenesis.  

PubMed

Centriolar satellites are proteinaceous granules that are often clustered around the centrosome. Although centriolar satellites have been implicated in protein trafficking in relation to the centrosome and cilium, the details of their function and composition remain unknown. FOP (FGFR1 Oncogene Partner) is a known centrosome protein with homology to the centriolar satellite proteins FOR20 and OFD1. We find that FOP partially co-localizes with the satellite component PCM1 in a cell cycle-dependent manner, similarly to the satellite and cilium component BBS4. As for BBS4, FOP localization to satellites is cell cycle dependent, with few satellites labeled in G1, when FOP protein levels are lowest, and most labeled in G2. FOP-FGFR1, an oncogenic fusion that causes a form of leukemia called myeloproliferative neoplasm, also localizes to centriolar satellites where it increases tyrosine phosphorylation. Depletion of FOP strongly inhibits primary cilium formation in human RPE-1 cells. These results suggest that FOP is a centriolar satellite cargo protein and, as for several other satellite-associated proteins, is involved in ciliogenesis. Localization of the FOP-FGFR1 fusion kinase to centriolar satellites may be relevant to myeloproliferative neoplasm disease progression. PMID:23554904

Lee, Joanna Y; Stearns, Tim

2013-03-12

367

FOP Is a Centriolar Satellite Protein Involved in Ciliogenesis  

PubMed Central

Centriolar satellites are proteinaceous granules that are often clustered around the centrosome. Although centriolar satellites have been implicated in protein trafficking in relation to the centrosome and cilium, the details of their function and composition remain unknown. FOP (FGFR1 Oncogene Partner) is a known centrosome protein with homology to the centriolar satellite proteins FOR20 and OFD1. We find that FOP partially co-localizes with the satellite component PCM1 in a cell cycle-dependent manner, similarly to the satellite and cilium component BBS4. As for BBS4, FOP localization to satellites is cell cycle dependent, with few satellites labeled in G1, when FOP protein levels are lowest, and most labeled in G2. FOP-FGFR1, an oncogenic fusion that causes a form of leukemia called myeloproliferative neoplasm, also localizes to centriolar satellites where it increases tyrosine phosphorylation. Depletion of FOP strongly inhibits primary cilium formation in human RPE-1 cells. These results suggest that FOP is a centriolar satellite cargo protein and, as for several other satellite-associated proteins, is involved in ciliogenesis. Localization of the FOP-FGFR1 fusion kinase to centriolar satellites may be relevant to myeloproliferative neoplasm disease progression.

Lee, Joanna Y.; Stearns, Tim

2013-01-01

368

Pluto has a satellite  

Microsoft Academic Search

A natural satellite of Pluto, tentatively designated Charon, was discovered in 1978 as a noticeable bulge on the photographic image of the planet Pluto. The orbit of the satellite is calculated to be circular, with a radius of about 20,000 km, inclination of 60 degrees and a period of 6.3867 days, equal to the period of rotation of Pluto around

G. Bodifee

1979-01-01

369

Satellites in Schools.  

ERIC Educational Resources Information Center

|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)|

Underwood, C. I.; And Others

1987-01-01

370

Devising geodetic satellite orbits  

Microsoft Academic Search

In the present paper, an intermediate theory of satellite motion, developed within the framework of the problem of six fixed centers with allowance for the influence of eight zonal harmonics of the geopotential, is applied to the analysis of quasi-geosynchronous and heliosynchronous orbits of geodetic satellites. Expressions for selecting nominal parameters for such orbits are proposed.

E. L. Lukashevich

1979-01-01

371

Ionospheric Research Using Satellites.  

National Technical Information Service (NTIS)

An account is given of the analysis of satellite transmissions recorded at Nairobi, Addis Ababa and Dar es Salaam. Work has been concentrated on the latitude and diurnal variation of total electron content (satellites BE-B and Canary Bird), the latitude v...

A. N. Hunter R. F. Kelleher

1968-01-01

372

Audio direct broadcast satellites  

NASA Astrophysics Data System (ADS)

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.

Miller, J. E.

1983-05-01

373

Interkosmos laser satellite rangefinder  

Microsoft Academic Search

A laser satellite rangefinder, with the capability of measuring distances up to 3,000 km with an accuracy to plus or minus 5 m was developed. The instrument includes: a pointing mechanism, photoelectric detector, time interval counter and a standard time service system. Five copies of this instrument have already been fabricated and are now operating at the artificial earth satellite

V. A. Yegorov

1978-01-01

374

Solar power satellite  

Microsoft Academic Search

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

R. J. Copeland; J. D. Martin

1983-01-01

375

ESRO applications satellites  

Microsoft Academic Search

The ESRO programs and their user oriented features and international cooperation aspects are stressed. A regional communication satellite system using frequencies around 12 GHz is being set up for Europe. An experimental preoperative satellite (OTS) with 5000 telephone channels and two television programs (Eurovision) or alternatively 6000 telephone channels, also carrying telecommunication experiments will be launched early in 1977. The

C. Rosetti; J. P. Contzen

1974-01-01

376

Signals from Communications Satellites.  

ERIC Educational Resources Information Center

|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)|

Thomsen, Volker

1996-01-01

377

Modular survivable satellite support  

Microsoft Academic Search

The development of a highly mobile, survivable satellite system from the Transportable Mobile Ground Station (T\\/MGS) is proposed. The addition of advanced capabilities to the T\\/MGS such as telemetry processing equipment, and the flexibility of a modularly designed system are examined. The need to increase survivability and mobility while reducing life cycle costs is discussed. A modular survivable satellite support

R. E. Wagner

1984-01-01

378

Internet Satellite Challenges  

Microsoft Academic Search

The current extension of communications, embracing terrestrial and space domains, raises a few legit questions in terms of business model, compatibility, and sustainability. Related to Internet satellites, this paper considers the following questions: Who are the US-based major operational Internet satellite organizations? What was the ambitious plan, and why did it fail? What are the basic incompatibilities of Internet and

William W. Wu

2010-01-01

379

Jovian and Saturnian satellites  

Microsoft Academic Search

The years 1983-1987 follow mankind's epochal first spacecraft encounters with the giant planets Jupiter and Saturn. Possibly the most spectacular “discoveries” there were the diversity and level of geological activity on the satellites that circle each. And part of the excitement no doubt stemmed from rebuttal of pre-encounter preconceptions, as the satellites of the inner solar system, while fascinating, are

William B. McKinnon

1987-01-01

380

MIMO over Satellite: A Review  

Microsoft Academic Search

The present article carries out a review of MIMO- based techniques that have been recently proposed for satellite communications. Due to the plethora of MIMO interpretations in terrestrial systems and the particularities of satellite communica- tions, this review is built on two pillars, namely fixed satellite and mobile satellite. Special attention is given to the characteristics of the satellite channel,

Pantelis-Daniel Arapoglou; Konstantinos Liolis; Massimo Bertinelli; Athanasios Panagopoulos; Panayotis Cottis; Riccardo De Gaudenzi

2011-01-01

381

Satellite services beyond 1990  

NASA Astrophysics Data System (ADS)

The commercial use of satellite-system services is discussed in terms of the services that can complement high-speed optical cables. The services currently offered are reviewed, and advances in fiber optics are evaluated to determine potential satellite-service markets. The advantages of satellite implementations include large coverage area, network flexibility, direct connections, and both multipoint-to-point and point-to-multipoint connections. Potential applications and services listed include multipoint and multilateral videoconferencing, computer/data communications, universal personal telecommunications, Ka-band bulk data transfer, satellite news gathering, and single-band VSATs. One important conclusion of the present review is that satellite designs should be driven by market/service considerations as opposed to technology.

Mohajeri, M.; Lo, Gerald; Subaran, Frank; Siachinji, Kenneth

1992-03-01

382

Dynamical Friction on Satellites  

NASA Astrophysics Data System (ADS)

Deienno et al 2011 (A&A, v.536, A57) investigated the effects of the planetary migration on the satellites of Uranus. We concluded that Uranus might have had more satellites than those observed today. However, due to the Late Heavy Bombardment (LHB) phenomenon, those satellites beyond Oberon were destabilized mostly by collisions involving themselves or with some regular ones. In this work we apply the same methodology for the Saturnian system. We found that the satellites with orbits inside Titan's orbit are immune to the LHB phenomenon. On the other hand, Hyperion, Iapetus, and even Titan, in some cases are strongly affected by the LHB, and depending on the value of Saturn's obliquity, Iapetus might not have resisted to the LHB event. We also found that, the final orbital elements of the surviving satellites differ from what we see today, mainly in inclination. While eccentricity and orbital semi-major axis can be easily damped by tides, for orbital inclinations, tidal effects are not so efficient. Thus, considering that eccentricity and orbital semi-major axis will still evolve by tides, to study the problem of the orbital inclination we consider that: according to our simulations, during the LHB event, collisions between planetesimals and satellites are a common event, causing in some cases destruction of satellites. So, we hypothesized that the material delivered by these catastrophic events could form a disc of particles around the remaining of satellites' orbits. This disc interacts with the remaining satellites and by dynamical friction phenomenon the orbital inclination can be damped. Some preliminary results have shown that, indeed, this tentative can be a viable way to damp conveniently the inclination of some satellites. Acknowledgement: FAPESP-CNPq

Deienno, Rogerio; Yokoyama, T.; Prado, A. F. B. A.

2012-10-01

383

The Turkey Ig-Like Receptor Family: Identification, Expression and Function  

PubMed Central

The chicken leukocyte receptor complex located on microchromosome 31 encodes the chicken Ig-like receptors (CHIR), a vastly expanded gene family which can be further divided into three subgroups: activating CHIR-A, bifunctional CHIR-AB and inhibitory CHIR-B. Here, we investigated the presence of CHIR homologues in other bird species. The available genome databases of turkey, duck and zebra finch were screened with different strategies including BLAST searches employing various CHIR sequences, and keyword searches. We could not identify CHIR homologues in the distantly related zebra finch and duck, however, several partial and complete sequences of CHIR homologues were identified on chromosome 3 of the turkey genome. They were designated as turkey Ig-like receptors (TILR). Using cDNA derived from turkey blood and spleen RNA, six full length TILR could be amplified and further divided according to the typical sequence features into one activating TILR-A, one inhibitory TILR-B and four bifunctional TILR-AB. Since the TILR-AB sequences all displayed the critical residues shown to be involved in binding to IgY, we next confirmed the IgY binding using a soluble TILR-AB1-huIg fusion protein. This fusion protein reacted with IgY derived from various gallinaceous birds, but not with IgY from other bird species. Finally, we tested various mab directed against CHIR for their crossreactivity with either turkey or duck leukocytes. Whereas no staining was detectable with duck cells, the CHIR-AB1 specific mab 8D12 and the CHIR-A2 specific mab 13E2 both reacted with a leukocyte subpopulation that was further identified as thrombocytes by double immunofluorescence employing B-cell, T-cell and thrombocyte specific reagents. In summary, although the turkey harbors similar LRC genes as the chicken, their distribution seems to be distinct with predominance on thrombocytes rather than lymphocytes.

Windau, Katharina; Viertlboeck, Birgit C.; Gobel, Thomas W.

2013-01-01

384

Effects of 28 days of resistance exercise and consuming a commercially available pre-workout supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers in males  

Microsoft Academic Search

PURPOSE: This study determined the effects of 28 days of heavy resistance exercise combined with the nutritional supplement, NO-Shotgun®, on body composition, muscle strength and mass, markers of satellite cell activation, and clinical safety markers. METHODS: Eighteen non-resistance-trained males participated in a resistance training program (3 × 10-RM) 4 times\\/wk for 28 days while also ingesting 27 g\\/day of placebo

Brian Shelmadine; Matt Cooke; Thomas Buford; Geoffrey Hudson; Liz Redd; Brian Leutholtz; Darryn S Willoughby

2009-01-01

385

Investigations on the protective role of passively transferred antibodies against avian metapneumovirus infection in turkeys.  

PubMed

The avian metapneumovirus (aMPV) is the causative agent of an acute respiratory disease in turkeys, which causes considerable economic losses to the poultry industry. Currently attenuated live and inactivated vaccines are widely used to control the disease, but vaccine breaks are frequently observed. For improvement of current vaccination strategies it is necessary to gain enhanced knowledge of the immune mechanisms against aMPV infection. Field observations suggest that vaccine-induced aMPV-specific antibodies are not indicative for protection. In the present study we investigated the role of antibodies in protection of turkeys against aMPV. In two experiments, commercial turkey poults received aMPV-specific antibodies by intravenous injection. The antibody transfer resulted in increased antibody levels in the sera. Virus-specific antibodies were also detected on mucosal surfaces such as the trachea, conjunctivae and gall bladder. Turkeys were subsequently challenged with a virulent aMPV subtype A strain. Development of clinical signs, virus detection by polymerase chain reaction and histopathological changes of tracheal mucosa in challenged turkeys with and without passively transferred antibodies were comparable with each other. Our results suggest that humoral immunity does not provide sufficient protection against aMPV infection. Thus, the measurement of vaccine-induced aMPV antibody response may not be considered as an adequate indicator of vaccine efficacy. Further research on the protective role of cell-mediated immune mechanisms is necessary to improve current vaccine strategies. PMID:19937531

Rubbenstroth, Dennis; Rautenschlein, Silke

2009-12-01

386

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

PubMed Central

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.

2013-01-01

387

Satellite Power Systems (SPS) cost review  

SciTech Connect

A study to determine estimated costs for three selected SPS designs is presented. One SPS concept uses silicon solar cells with a concentration ratio of one; one concept uses gallium arsenide solar cells with a concentration ratio of two; and the third (reference) design incorporates features of the first two. Selected system definition assumptions and cost estimating relationships for each of the three SPS concept designs were independently reviewed. The systems within the SPS designs chosen include: rectenna construction, graphite fiber reinforced thermoplastic structures, solar cells, satellite electrical slip rings, satellite electrical systems, and ground rectenna electrical systems. Procedures and results are detailed. (WHK)

Crowley, J.H.; Ziegler, E.J.

1980-05-01

388

Energy related environmental policies in Turkey  

SciTech Connect

There is increasing consensus in both the scientific and political communities that significant reductions in greenhouse gas (GHG) emissions are necessary to limit the magnitude and extent of climate change. Renewable energy systems already reduce GHG emissions from the energy sector, although on a modest scale. Turkey is heavily dependent on expensive imported energy resources (oil, gas, and coal) that place a big burden on the economy, and air pollution is becoming a great environmental concern in the country. In this regard, renewable energy resources appear to be one of the most efficient and effective solutions for clean and sustainable energy development in Turkey. Turkey's geographical location has several advantages for extensive use of most of these renewable energy sources. This article presents a review of the energy related environmental policies in Turkey.

Kaygusuz, K.; Bilgen, S. [Karadeniz Technical University, Trabzon (Turkey). Dept. of Chemistry

2008-07-01

389

Habitat Suitability Index Models: Eastern Wild Turkey.  

National Technical Information Service (NTIS)

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...

R. L. Schroeder

1985-01-01

390

Poult adoption in Merriam's wild turkeys  

Treesearch

P.O. Box 96090 ... If males are removed from monogamous pairs after breeding, replacement males may fill the openings and adopt the brood (Martin 1989). ... Keywords: turkeys, Meleagris gallopavo merriami, poults, Black Hills, South ...

391

Standardization and Measurement Services in Turkey.  

National Technical Information Service (NTIS)

The survey of standardization and measurement services for developing industries in Turkey has been carried out by NBS with funding by AID, with participation by representatives of Ecuador and Korea, and under the guidance of the Turkish Standards Institu...

H. S. Peiser R. J. Corruccini S. B. Newman

1972-01-01

392

Swedish small satellites  

NASA Astrophysics Data System (ADS)

In 1986 the first Swedish small satellite VIKING was launched on the Ariane 1 rocket together with the French remote sensing satellite SPOT-1. This paper describes the development of Swedish small satellites in an international framework. The satellites have delivered excellent scientific data to a low cost by using e.g. streamlined project organisations, competitive procurement programs and piggy-back launch opportunities. The first micro satellite Astrid-1 was launched in January 1995 and was followed by the launch of Astrid-2 in December 1998. The capable Odin small satellite was launched in February 2001. SSC was also contracted for ESA's SMART-1 probe destined to the Moon. SMART-1, launched in September 2003, is used for both research and as a technology demonstrator for future projects. Future proposed projects include micro and small satellites for climate research as the Atmosphere and Climate Explorer Plus (ACE+), the Stratosphere-Troposphere Exchange And climate Monitor (STEAM) and PRISMA, a technology demonstrator for formation flying, new propulsion system and commercial development methods.

Lundahl, K.; von Scheele, F.

2004-11-01

393

Iridium Satellite Signal Exploitation  

NASA Astrophysics Data System (ADS)

The Iridium Satellite constellation is unique to satellite communication networks in that it allows for transmission of data between satellites instead of relying on transmission by the bent pipe methodology. As such, this network is far more secure than other satellite communication networks, and forces interception to occur within the locale of the transmission from modem to satellite or within the locale of the downlink from the satellite other modem. The purpose of this project was to demonstrate the security weaknesses within the Iridium protocol, showing that it was possible to track one of these satellites with a high gain antenna, resulting in the ability to anticipate transmission, to acquire the location of that transmission, and to uncover the content of that transmission. This project was completed as part of the summer student program at the Southwest Research Institute. The presentation will demonstrate the thought process used in chronological order, essentially demonstrating how I achieved the result from my point of view as the summer progressed.

McDonough, Peter

2010-03-01

394

Small satellite launch system  

NASA Astrophysics Data System (ADS)

The World Administrative Radio Conference (WARC 92) delegates agreed to worldwide frequency allocation changes that will introduce new space communications services through low earth orbit (LEO) satellite systems. Iridium, Odyssey and Orbcomm are major proposals for these services, and each proposal is to launch 77, 12 and 18 small communications satellites. In this way, the new era of small satellites is going to be initiated. The anticipation of the expansion of the small satellite launch market, new cost-effective and flexible launch systems have been developed. In 1990 Orbital Science Corp. successfully completed the maiden flight of the PEGASUS winged launch vehicle and now has been developing the new TAURUS launch vehicle. Arianespace successfully completed two ASAP (Arian Structure for Auxiliary Payloads) missions, and its new small satellites deployment system is in the process of development. McDonnel Douglas is thinking of Delta II launch vehicle applications for small satellites. This trend is seen to continue through the 1990s. This paper describes the trend of the small satellite launch market and the availability of a planned launch system in Japan.

Kochiyama, Jiro

395

Electricity Generation From Dams in Turkey  

Microsoft Academic Search

As a result of growing environmental consciousness, renewable energy sources such as hydropower are preferred. It is generated from domestic sources and is also the cheapest in terms of cost. In 2007, the annual electricity production of Turkey reached 191,558.1 GWh of which 35,850.8 GWh came from hydropower plants. The economically and technically exploitable potential of Turkey is 127,000 GWh\\/yr.

K. Günaydin

2012-01-01

396

TEWI—Turkey Early Warning Index  

Microsoft Academic Search

TEWI—Turkey Early Warning Index is a combination of eight different indexes that basically stands on eight different macroeconomic variables. Each variable was selected in accordance with the strength of reflecting macroeconomic outlook. Analysis of the macroeconomic variables shows that all variables have almost the same transactions in pre-crisis terms. The difference of TEWI—Turkey Early Warning Index from the current early

Sercan Kiliclar; Oktay Tas

2009-01-01

397

A case of salinomycin intoxication in turkeys  

PubMed Central

Abstract 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.

2006-01-01

398

Extragonadal teratoma in a domestic turkey (Meleagris gallopavo domestica).  

PubMed

This is the first report of a primary, spontaneous and, most probably, congenital teratoma in a domestic turkey, localized in front of the left eyeball. The unique localization allowed surgical excision of the tumour. The histopathological examination revealed that the tumour included structures derived from all three germ cell layers: ectoderm, mesoderm and endoderm (e.g. cartilaginous, osseous, haematopoietic, fibrous, nervous, glandular, squamous epithelial and smooth muscle tissues). The presence of epithelial cells as well as smooth muscle cells was confirmed using anti-cytokeratin and anti-desmin antibodies, respectively. The proliferative activity of the tumour cells was confirmed using proliferating cell nuclear antigen immunostaining. The other cases of teratoma in wild and domestic birds are reviewed briefly. PMID:22702456

Pa?dzior, Katarzyna; Szweda, Magdalena; Otrocka-Domaga?a, Iwona; Rotkiewicz, Tadeusz

2012-01-01

399

Identification and location of the structural glycoproteins of a tissue culture-adapted turkey enteric coronavirus  

Microsoft Academic Search

Summary The Minnesota strain of turkey enteric coronavirus (TCV) was grown on a human rectal tumor (HRT-18) cell line in the presence of radiolabeled amino acids and glucosamine to analyse virion structural proteins. In addition to the 52,000 unglycosylated nucleocapsid protein, three major glycoprotein species were found to be associated with the viral envelope. A predominant glycosylated protein with a

S. Dea; S. Garzon; P. Tijssen

1989-01-01

400

LOCALIZATION OF AQUAPORINS IN THE SPERM STORAGE TUBULES IN THE TURKEY OVIDUCT  

Technology Transfer Automated Retrieval System (TEKTRAN)

Oviductal sperm storage tubules (SST), located at the uterovaginal junction, are the primary site of sperm storage in turkeys. Sperm reside within these storage sites and may be released via a dynamic interaction between sperm mobility and a fluid current generated by the SST epithelial cells. In th...

401

Precipitating antigens associated with Marek's disease viruses and a herpesvirus of Turkeys  

Microsoft Academic Search

Precipitating antigens associated with a number of Marek's disease virus strains and with a turkey herpesvirus have been analyzed. The ‘A’ antigen has been defined as the major soluble antigen in feather follicles of infected chickens, which is identical with the major antigen usually present in supernatants of chicken kidney cell cultures infected with strains of Marek's disease virus. ‘BC’

V. v. Bülow; P. M. Biggs

1975-01-01

402

Inducement of enlarged hearts and muscular dystrophy in turkey poults with dietary silver  

Microsoft Academic Search

Five experiments were conducted to determine the effect of adding silver acetate or nitrate to practical diets on growth of Large White turkey poults and incidence of pathological signs. The highest level of silver (900 p.p.m.) depressed growth rate, reduced packed cell volume, slightly reduced hemoglobin level and caused cardiac enlargement. The high silver level also induced a varying incidence

L. S. Jensen; R. P. Peterson; L. Falen

1974-01-01

403

DIFFERENTIAL HETEROPHIL INTRACELLULAR SIGNALING AND FUNCTIONS IN WILD-TYPE AND COMMERCIAL TURKEYS  

Technology Transfer Automated Retrieval System (TEKTRAN)

A comparison of cell signaling and functions in heterophils from a commercial line (A) to wild-type Rio Grande turkeys days 4 and 7 post-hatch was conducted. Mitogen-activated protein kinases (MAPK) p38 and ERK 1/2 and total protein tyrosine kinase (PTK) activities were measured. After stimulation...

404

Satellite Tracking Threatened Species  

NSDL National Science Digital Library

The Patuxent Wildlife Research Center and NASA's Goddard Space Flight Center have combined forces to produce this Website on the use of satellite tracking to monitor migration routes of endangered birds. Targeting the general public, the site introduces readers to satellite tracking (using Direct Readout technology), offers animations of bird flight paths (see the section entitled Birdtracks), and gives additional information on birds (in the Bird Data Archives, select a bird and watch its flight path through time). While bird information is limited to several larger species (due to the size/weight of attached transmitters), the resource serves as a useful information base for anyone wishing to learn more about satellite tracking.

405

JOI reaffirms satellite plan  

NASA Astrophysics Data System (ADS)

A recent report by the Satellite Planning Committee of Joint Oceanographic Institutions, Inc. (JOI), Washington, D.C., underscored the need for the four oceanographic satellite missions that have been proposed for the next decade to be carried out as planned and firmly on schedule. In reaffirming the need for the missions, the committee said that many important types of long-term global data auoui ihe oceans can be gathered only by research satellites. The potential benefits to vital national activities such as trade, fisheries, national defense, and waste disposal will be well worth the missions' cost, they added.

Katzoff, Judith A.

406

Joint polar satellite system  

NASA Astrophysics Data System (ADS)

The Joint Polar Satellite System (JPSS) is a joint NOAA/NASA mission comprised of a series of polar orbiting weather and climate monitoring satellites which will fly in a sun-synchronous orbit, with a 1330 equatorial crossing time. JPSS resulted from the decision to reconstitute the National Polar-orbiting Operational Environmental Satellite System (NPOESS) into two separate programs, one to be run by the Department of Defense (DOD) and the other by NOAA. This decision was reached in early 2010, after numerous development issues caused a series of unacceptable delays in launching the NPOESS system.

Trenkle, Timothy; Driggers, Phillip

2011-10-01

407

Sulfachlorpyrazine residues depletion in turkey edible tissues.  

PubMed

Sulfachlorpyrazine (SCP) is currently used to treat coccidian infections in turkeys; however, there is no information available about the withdrawal period necessary for the turkey to be safe for human consumption. A high performance liquid chromatography method with ultraviolet-visible light detection was adapted and validated for the determination of SCP in turkey tissues. The procedure is based on isolation of the (SCP sodium) compound from edible turkey tissues (muscles, liver, kidneys, and fat with skin) with satisfactory recovery (72.80 +/- 1.40) and specificity. The residue depletion of SCP in turkeys was conducted after a dose of 50 mg/kg body weight/day had been administrated orally for 3 days. After treatment has been discontinued residue concentrations were detected in tissues on the 7th day. The highest SCP concentrations were measured in muscles. Based on the results presented in this study, it could be assumed that a withdrawal period of 21 days, before medicated turkeys could be slaughtered, would be sufficient to ensure consumer safety. PMID:20646202

?ebkowska-Wieruszewska, B I; Kowalski, C J

2010-08-01

408

PATHOLOGY AND VIRUS TISSUE DISTRIBUTION OF TURKEY ORIGIN REOVIRUSES IN EXPERIMENTALLY INFECTED TURKEY POULTS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The pathogenesis of four isolates of turkey-origin reovirus (TRV) and one chicken-origin reovirus was examined by infecting specific pathogen free (SPF) poults. These TRV isolates were collected from turkey flocks experiencing poult enteritis and are genetically distinct from previously reported avi...

409

Turkey vulture and California condor  

USGS Publications Warehouse

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.

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

1989-01-01

410

Using Cell Phones From Satellites.  

National Technical Information Service (NTIS)

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 (S...

S. Horan

2000-01-01

411

Caldera formation at Tendurek, East Turkey  

NASA Astrophysics Data System (ADS)

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 algorithm for the optimization and accounting for model uncertainties by using the data error variance covariance matrix an Okada source is best explaining the signal and suggests a sill like intrusion subject to deflation or cooling. After the subtraction of the synthetic deformation due to this source, the residual deformation velocity shows a ring like structure that is aligned with the previously mentioned ring fault system. Thus the observed deformation signal might be also explained by the subsidence along these ring faults.

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

2012-04-01

412

Advanced Satellite Communication System.  

National Technical Information Service (NTIS)

The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer...

E. J. Staples S. Lie

1992-01-01

413

Aiming a Satellite Dish.  

ERIC Educational Resources Information Center

Develops a pair of equations for calculating the elevation and azimuth angles for the various satellites. Uses 3-dimensional vector difference calculations. Provides a practical example, figures, and table. (YP)

Zebrowski, Ernest, Jr.

1988-01-01

414

Commercial Satellite Leased Capacity.  

National Technical Information Service (NTIS)

This report is the fourth in a series resulting from our audit, 'Communications Capability Within DoD to Support Two Major Regional Conflicts Nearly Simultaneously'. This report discusses the management, procurement, and usage of commercial satellite syst...

1999-01-01

415

NASA: Satellite Tracking  

NSDL National Science Digital Library

While NASA has offered a number of fine sites about their research for the general public over the years, this particular site may be one of their best. With a minimum of fuss, visitors can use several of the online tracking applications offered here to locate hundreds of satellites and other such large objects in space. A good way to start a visit to this site is by taking a look at the J-Track 2.5 section, as it offers a quick way to find out the current location of the Space Station and the Chandra X-Ray Observatory. Additionally, visitors can also locate weather satellites using this application. The Live 3D Java Tracking Display here allows visitors to monitor close to 700 satellites that are in motion around the earth. Finally, visitors can also use a handy application offered here that allows them to determine which satellites might be seen from their location in the night sky.

2005-01-01

416

Satellite Power System (SPS).  

National Technical Information Service (NTIS)

Potential organizational options for a solar power satellite system (SPS) were investigated. Selection and evaluation criteria were determined to include timeliness, reliability, and adequacy to contribute meaningfully to the U.S. supply; political feasib...

H. G. Edler

1978-01-01

417

Civil satellite navigation systems  

NASA Astrophysics Data System (ADS)

The use of satellite navigation for civil purposes is examined critically to compare the merits and costs of existing and practical satellite systems. Accuracy and range considerations are reviewed, and the basic requirements of radionavigation systems are set forth. Specific data are given regarding coverage area, integration with ground-based systems, monitoring and control, and accuracy. Systems reviewed include 'Starfix,' Inmarsat, EVA Vavsat, and Geostar/Locstar/Omnitracs, and extensive illustrations are provided to demonstrate constellation geometries. When in view, two or three geosynchronous satellites can provide acceptable fixing, and 9 satellites can provide global coverage. It is argued that systems such as 'Starfix' are commercially viable with less than 100 users, and Inmarsat is identified as an effective European civil system.

Blanchard, Walter F.

1991-07-01

418

Satellite Research Group  

NSDL National Science Digital Library

NOAA's Ocean Remote Sensing Division runs the Satellite Research Group, which uses data from environmental satellites to study seasonal and interannual climate variability. Research areas include air-sea interaction (and transfers of heat, momentum, and water); the global hydrological cycle (including water vapor and precipitation); the Earth's radiation budget; and real-time monitoring of the El Nino/La Nina oscillation. Each research area is described in detail at the Website, and links connect users to the latest real-time geostationary satellite data images, as well as to the absolutely spectacular climate image archives. For researchers interested in regional or global scale climate patterns or the use of satellite technology for research purposes, this is an excellent resource.

419

Overview of commercial satellite communications  

NASA Astrophysics Data System (ADS)

A brief history of communications satellites is presented, taking into account the launching of Sputnik 1 in October 1957, the Explorer 1 in January of 1958, the launch of the Score as the world's first active communications satellite in December 1958, the Communications Satellite Act in 1962, and the launch of 'Early Bird' in 1964. The Intelsat satellites are considered along with maritime satellite communications, the U.S. domestic satellite systems, Alaskan satellite communications, cable television, broadcast TV stations, print media, the hotel/motel industry as a large market for satellite communications terminals, the opening of a minicable and satellite master antenna TV market for TV receive-only systems, and business telecommunications earth terminals. Attention is also given to future directions regarding satellite positions, the concept of 'video-plus', and direct broadcast satellites.

Beakley, G. W.

1984-07-01

420

Radio determination satellite service  

NASA Astrophysics Data System (ADS)

The capabilities and measured performance of a geosynchronous satellite-based service called the radio determination satellite service (RDSS), which operates at radio frequencies allocated by the International Telecommunications Union (ITU) and is licensed in the United States by the Federal Communications Commission (FCC), are discussed. Plans for both improvement in capability and expansion to nearly global coverage are described. Since RDSS can also provide radio navigation, some comparisons of this service with the Global Positioning System (GPS) are made.

Briskman, Robert D.

1990-07-01

421

Sea Turtle Satellite Tracking  

NSDL National Science Digital Library

Near real-time tool for collecting, managing and sharing marine life satellite tracking data. Over 30 projects in US, Caribbean, Mediterranean, Indo-Pacific, and Australian waters. Provides links to background information for each project, the animals they are tracking, and maps that are updated regularly. Teaching resources include maps for tracking, suggestions for using data in lessons on geography, biology, earth science, math. Good introduction to satellite telemetry methodology and applications.

422

Launching a Satellite  

NSDL National Science Digital Library

Isaac NewtonÂs famous thought experiment about what would happen if you launched a cannon from a mountaintop at a high velocity comes to life with an interactive computer model. You are charged with the task of launching a satellite into space. Control the angle and speed at which the satellite is launched, and see the results to gain a basic understanding of escape velocity.

Consortium, The C.

2011-12-11

423

G-MG Satellite  

NSDL National Science Digital Library

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important asects of the task and its potential use. Here are the first few lines of the commentary for this task: A satellite orbiting the earth uses radar to communicate with two control stations on the earth's surface. The satellite is in a geostationary orbit. T...

424

Data communications via satellite  

NASA Astrophysics Data System (ADS)

The Americom satellite communications system is described with respect to data service offerings that range from teletype traffic to wideband services in excess of 60 Mbps. Present wideband services are discussed, along with voice bandwidth data, satellite channel delay, bit rate variations, and the commercial wideband data system known as 56 Plus. Attention is given to the forward error correction, TDMA transmission, terminal operation, and piggyback data on TV distribution.

Langhans, R. A.; Mitchell, T. H.

1980-12-01

425

Satellite clocks characterization and monitoring for global navigation satellite systems  

Microsoft Academic Search

In Global Navigation Satellite Systems (GNSS) the user’s position is determined measuring the time of flight of the signals broadcast from satellites, which is proportional to the distance between the user and each satellite of the constellation. Time and frequency metrology has an essential role in satellite navigation systems: since a distance can be measured from a time, any error

A. Cernigliaro; I. Sesia

2011-01-01

426

Turkey's Iran Card: Energy Cooperation in American and Russian Vortex.  

National Technical Information Service (NTIS)

This thesis analyzes the consequences of Turkey's natural gas cooperation with Iran. Two countries initiated cooperation in natural gas sales and transportation to Turkey and Europe. However, conflicting interests of many actors in energy issues make find...

E. Dogan

2004-01-01

427

78 FR 55095 - Certain Pasta From Italy and Turkey  

Federal Register 2010, 2011, 2012, 2013

...Review)] Certain Pasta From Italy and Turkey Determinations On the basis of the record...orders on certain pasta from Italy and Turkey would be likely to lead to continuation...respect to imports of certain pasta from...

2013-09-09

428

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

PubMed

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

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

2013-04-29

429

Ultrastructural study of turkey rhinotracheitis virus infection in turbinates of experimentally infected chickens.  

PubMed

Ultrastructural changes associated with turkey rhinotracheitis virus infection were studied in turbinates of chickens experimentally infected with the isolate CVL 14/86/1. Chickens were sacrificed at 3, 5 and 7 days after inoculation and samples of the middle turbinate were taken, fixed, dehydrated and embedded in an hydrophilic resin. An immunofluorescence technique on semithin sections was carried out and viral antigen was observed in the cytoplasm and associated to cilia of the turbinate epithelial cells, on days 3 and 5 after inoculation. Ultrastructurally, gold stained intracytoplasmic nucleocapsid aggregates of turkey rhinotracheitis virus were observed in ciliated and non-ciliated epithelial cells, as well as budding virus particles, at days 3 and 5 postinoculation. Different ultrastructural abnormalities, including cytoplasmic blebs, clumping and loss of cilia were observed in the apical cell membrane of many infected cells, associated with the presence of intracytoplasmic inclusions. On day 5 after inoculation, substitution of ciliated and non-ciliated epithelial cells was noted and many desquamated epithelial cells were observed within the lumina. Regenerative changes in the ciliated epithelium were observed by day 7 postinoculation. These results indicate that turkey rhinotracheitis virus is able to replicate in ciliated and non-ciliated epithelial cells causing severe alterations to the cell surface and ciliary apparatus of the turbinate epithelium. Viral-induced damage to the turbinate epithelium could enhance the susceptibility of epithelial cells to secondary bacterial infection. PMID:8914249

Majó, N; Martí, M; O'Loan, C J; Allan, G M; Pagès, A; Ramis, A

1996-09-01

430

Overview of commercial satellite communications  

Microsoft Academic Search

A brief history of communications satellites is presented, taking into account the launching of Sputnik 1 in October 1957, the Explorer 1 in January of 1958, the launch of the Score as the world's first active communications satellite in December 1958, the Communications Satellite Act in 1962, and the launch of 'Early Bird' in 1964. The Intelsat satellites are considered

G. W. Beakley

1984-01-01

431

Direct Broadcasting Satellites in Japan.  

ERIC Educational Resources Information Center

|The development and use of broadcasting satellites in Japan are discussed in this paper. The paper describes the medium-scale experimental broadcasting satellite, YURI, launched by NASA in 1978, and reports that experiments with YURI in the areas of basic technologies in the broadcasting satellite system, experiments on satellite control…

Maeda, Jiro

432

Educational Technology in Turkey: Past, Present and Future.  

ERIC Educational Resources Information Center

|Explains the past, discusses the present, and makes projections for the future of educational technology in Turkey. Topics include historical background of Turkey and of educational technology in Turkey; the role of the Ministry of National Education; distance education; technology-based education; and the national information infrastructure.…

Akkoyunlu, Buket

2002-01-01

433

Overview of the photovoltaic technology status and perspective in Turkey  

Microsoft Academic Search

The Republic of Turkey, located in Southeastern Europe and Southwestern Asia (that portion of Turkey west of the Bosporus is geographically part of Europe). Nowadays, Turkey with its young population and growing energy demand per person, its fast growing urbanization, and its economic development, has been one of the fast growing electrical energy markets of the world for the last

Furkan Dinçer

2011-01-01

434

Assessment of Rural Tourism in Turkey Using SWOT Analysis  

Microsoft Academic Search

In the study, current and future situations of rural tourism in Turkey were criticized by means of SWOT analysis technique. As a result, Turkey has important rural tourism potential, but initiatives, investments and promotion for rural tourism are inadequate and slow compared to main tourism destinations in Mediterranean countries. Turkey can be one of the most important rural tourism centres

Hasan Akca

2006-01-01

435

Survey of Kansas Wild Turkey Hunters: Experiences, Opinions, and Satisfactions  

Microsoft Academic Search

Wild turkeys (Meleagris gallopavo) have become an important game species in Kansas since the first season opened in 1974. We surveyed Kansas turkey hunters to determine their demographic characteristics, hunting experiences, opinions, and satisfactions. We mailed 642 questionnaires to hunters who bought spring or fall turkey permits during the 1998-1999 seasons. Of these questionnaires, 33 were returned undeliverable and 403

Roger D. Applegate; Ted T. Cable; Philip S. Gipson

436

Hydropower Energy Versus Other Energy Sources in Turkey  

Microsoft Academic Search

Hydroelectric energy is one of the major renewable energy resources in Turkey. Turkey's gross hydropower potential is estimated as 433–442 terawatt hours\\/year; that is equal to 1% of world and 14% of European hydropower potential. This article presents the historical development, potential, and current status of hydropower, and examines the current role hydropower is playing in Turkey, along with some

M. ?. Kömürcü; A. Akpinar

2010-01-01

437

Electric Power Plants and Electricity Generation in Turkey  

Microsoft Academic Search

Electricity demand in Turkey grows rapidly as a result of the rate of population growth, a rapid industrialization, and economic development. When the Republic of Turkey was founded in 1923, its installed capacity of electricity production and the total electricity production were only 33 MW and 45 GWh, respectively. But, Turkey's installed power capacity reached 38,843.5 MW with an annual

M. Bilgili; B. ?ahin

2009-01-01

438

Naturally occurring clinical reticuloendotheliosis in Turkeys and chickens  

Microsoft Academic Search

Outbreaks of clinical reticuloendotheliosis (RE) were observed in a turkey flock and two pullet flocks. Clinical signs in turkeys included sleepiness, weakness, anorexia, diarrhoea and reduced egg production. The pullets showed severe emaciation, loss of back feathers, anorexia and diarrhoea. Fifteen out of 54 turkeys died before the flock was killed. One pullet flock suffered 20% mortality while the other

J. O. A. Okoye; W. Ezema; J. N. Agoha

1993-01-01

439

Everyday Engineering: Time's up, turkey--Pop-up thermometers  

NSDL National Science Digital Library

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