244 research outputs found
Subcutaneous Neurotophin 4 Infusion Using Osmotic Pumps or Direct Muscular Injection Enhances Aging Rat Laryngeal Muscles
Laryngeal dysfunction in the elderly is a major cause of disability, from voice disorders to dysphagia and loss of airway protective reflexes. Few, if any, therapies exist that target age-related laryngeal muscle dysfunction. Neurotrophins are involved in muscle innervation and differentiation of neuromuscular junctions (NMJs). It is thought that neurotrophins enhance neuromuscular transmission by increasing neurotransmitter release. The neuromuscular junctions (NMJs) become smaller and less abundant in aging rat laryngeal muscles, with evidence of functional denervation. We explored the effects of NTF4 for future clinical use as a therapeutic to improve function in aging human laryngeal muscles. Here, we provide the detailed protocol for systemic application and direct injection of NTF4 to investigate the ability of aging rat laryngeal muscle to remodel in response to NTF4 application. In this method, rats either received NTF4 either systemically via osmotic pump or by direct injection through the vocal folds. Laryngeal muscles were then dissected and used for histological examination of morphology and age-related denervation
Sports review: A content analysis of the International Review for the Sociology of Sport, the Journal of Sport and Social Issues and the Sociology of Sport Journal across 25 years
The International Review for the Sociology of Sport, the Journal of Sport and Social Issues and Sociology of Sport Journal have individually and collectively been subject to a systematic content analysis. By focusing on substantive research papers published in these three journals over a 25-year time period it is possible to identify the topics that have featured within the sociology of sport. The purpose of the study was to identify the dominant themes, sports, countries, methodological frameworks and theoretical perspectives that have appeared in the research papers published in these three journals. Using the terms, identified by the author(s), that appear in the paper’s title, abstract and/or listed as a key word, subject term or geographical term, a baseline is established to reflect on the development of the sub-discipline as represented by the content of these three journals. It is suggested that the findings illustrate what many of the more experienced practitioners in the field may have felt subjectively. On the basis of this systematic, empirical study it is now possible to identify those areas have received extensive coverage and those which are under-researched within the sociology of sport. The findings are used to inform a discussion of the role of academic journals and the recent contributions made by Michael Silk, David Andrews, Michael Atkinson and Dominic Malcolm on the past, present and future of the ‘sociology of sport’
Enhancement of Aging Rat Laryngeal Muscles with Endogenous Growth Factor Treatment
Clinical evidence suggests that laryngeal muscle dysfunction is associated with human aging. Studies in animal models have reported morphological changes consistent with denervation in laryngeal muscles with age. Life‐long laryngeal muscle activity relies on cytoskeletal integrity and nerve–muscle communication at the neuromuscular junction (NMJ). It is thought that neurotrophins enhance neuromuscular transmission by increasing neurotransmitter release. We hypothesized that treatment with neurotrophin 4 (NTF4) would modify the morphology and functional innervation of aging rat laryngeal muscles. Fifty‐six Fischer 344xBrown Norway rats (6‐ and 30‐mo age groups) were used to evaluate to determine if NTF4, given systemically (n = 32) or directly (n = 24), would improve the morphology and functional innervation of aging rat thyroarytenoid muscles. Results demonstrate the ability of rat laryngeal muscles to remodel in response to neurotrophin application. Changes were demonstrated in fiber size, glycolytic capacity, mitochondrial, tyrosine kinase receptors (Trk), NMJ content, and denervation in aging rat thyroarytenoid muscles. This study suggests that growth factors may have therapeutic potential to ameliorate aging‐related laryngeal muscle dysfunction
Representations of sport in the revolutionary socialist press in Britain, 1988–2012
This paper considers how sport presents a dualism to those on the far left of the political spectrum. A long-standing, passionate debate has existed on the contradictory role played by sport, polarised between those who reject it as a bourgeois capitalist plague and those who argue for its reclamation and reformation. A case study is offered of a political party that has consistently used revolutionary Marxism as the basis for its activity and how this party, the largest in Britain, addresses sport in its publications. The study draws on empirical data to illustrate this debate by reporting findings from three socialist publications. When sport did feature it was often in relation to high profile sporting events with a critical tone adopted and typically focused on issues of commodification, exploitation and alienation of athletes and supporters. However, readers’ letters, printed in the same publications, revealed how this interpretation was not universally accepted, thus illustrating the contradictory nature of sport for those on the far left
NASA's Robotic Lunar Lander Development Program
NASA Marshall Space Flight Center and the Johns Hopkins University Applied Physics Laboratory have developed several mission concepts to place scientific and exploration payloads ranging from 10 kg to more than 200 kg on the surface of the moon. The mission concepts all use a small versatile lander that is capable of precision landing. The results to date of the lunar lander development risk reduction activities including high pressure propulsion system testing, structure and mechanism development and testing, and long cycle time battery testing will be addressed. The most visible elements of the risk reduction program are two fully autonomous lander flight test vehicles. The first utilized a high pressure cold gas system (Cold Gas Test Article) with limited flight durations while the subsequent test vehicle, known as the Warm Gas Test Article, utilizes hydrogen peroxide propellant resulting in significantly longer flight times and the ability to more fully exercise flight sensors and algorithms. The development of the Warm Gas Test Article is a system demonstration and was designed with similarity to an actual lunar lander including energy absorbing landing legs, pulsing thrusters, and flight-like software implementation. A set of outdoor flight tests to demonstrate the initial objectives of the WGTA program was completed in Nov. 2011, and will be discussed
The Notochord, Notochordal cell and CTGF/CCN-2: ongoing activity from development through maturation
The growth regulating factor CTGF/CCN-2 is an integral factor in growth and development, connective tissue maintenance, wound repair and cell cycle regulation. It has recently been reported that CTGF/CCN-2 is involved in very early development having been detected in early notochord formation in zebrafish using CTGF/CCN-2 promoter-driven green fluorescent protein (GFP) plasmids. In these studies fluorescence was detected early in the developing embryos, a finding of considerable significance in that CTGF/CCN-2 deficient mutant mice die early after birth due to severe cartilage and skeletal dysplasia and respiratory failure. Such findings confirm the importance of CTGF/CCN-2 in development and of the necessary and sufficient role of this molecule in formation of the skeleton, extracellular matrix and chondrogenesis. Of particular relevance to the relationship between the notochordal cell and CTGF/CCN-2 there is a remarkable sub-species of canine, the ‘non-chondrodystrophic’ canine that is protected from developing degenerative disc disease (DDD). These animals are unique in that they preserve the population of notochordal cells within their disc nucleus (NP) and these cells secrete CTGF/CCN-2. We have detected CTGF/CCN-2 within conditioned medium developed from the notochordal cells of these animals (NCCM) and used this conditioned medium to demonstrate robustly increased proteoglycan production. The addition of recombinant human CTGF/CCN-2 to totally serum-free media containing cultures of bovine NP cells replicated the robustly increased aggrecan gene expression found with NCCM alone strongly suggesting the importance of the effect of CTGF/CCN-2 in notochordal cell biology within the disc nucleus of non-chondrodystrophic canines. The chondrodystrophic canine, another sub-species on the other hand are almost totally devoid of notochordal cells and they develop DDD profoundly and early. These two sub-species of canine reflect a naturally occurring animal model that is an excellent example of differential notochordal cell survival and possible associated developmental differences in extracellular maintenance
Automatic Regulation of Hemodynamic Variables in Acute Heart Failure by a Multiple Adaptive Predictive Controller Based on Neural Networks
A Loss of Function Screen of Identified Genome-Wide Association Study Loci Reveals New Genes Controlling Hematopoiesis
The formation of mature cells by blood stem cells is very well understood at the cellular level and we know many of the key transcription factors that control fate decisions. However, many upstream signalling and downstream effector processes are only partially understood. Genome wide association studies (GWAS) have been particularly useful in providing new directions to dissect these pathways. A GWAS meta-analysis identified 68 genetic loci controlling platelet size and number. Only a quarter of those genes, however, are known regulators of hematopoiesis. To determine function of the remaining genes we performed a medium-throughput genetic screen in zebrafish using antisense morpholino oligonucleotides (MOs) to knock down protein expression, followed by histological analysis of selected genes using a wide panel of different hematopoietic markers. The information generated by the initial knockdown was used to profile phenotypes and to position candidate genes hierarchically in hematopoiesis. Further analysis of brd3a revealed its essential role in differentiation but not maintenance and survival of thrombocytes. Using the from-GWAS-to-function strategy we have not only identified a series of genes that represent novel regulators of thrombopoiesis and hematopoiesis, but this work also represents, to our knowledge, the first example of a functional genetic screening strategy that is a critical step toward obtaining biologically relevant functional data from GWA study for blood cell traits
Multifactorial Origins of Heart and Gut Defects in nipbl-Deficient Zebrafish, a Model of Cornelia de Lange Syndrome
nipbl-deficient zebrafish provide evidence that heart and gut defects in Cornelia de Lange Syndrome are caused by combined effects of multiple gene expression changes that occur during early embryonic development
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