952 research outputs found

    Three Hierarchies in Skeletal Muscle Fibre Classification Allotype, Isotype and Phenotype

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    Immunocytochemical analyses using specific anti-myosin antibodies of mammalian muscle fibers during regeneration, development, and after denervation have revealed two distinct myogenic components determining fiber phenotype. The jaw-closing muscles of the cat contain superfast fibers which express a unique myosin not found in limb muscles. When superfast muscle is transplanted into a limb muscle bed, regenerating myotubes synthesize superfast myosin independent of innervation. Reinnervation by the nerve to a fast muscle leads to the expression of superfast and not fast myosin, while reinnervation by the nerve to a slow muscle leads to the expression of a slow myosin. When limb muscle is transplanted into the jaw muscle bed, only limb myosins are synthesized. Thus jaw and limb muscles belong to distinct allotypes, each with a unique range of phenotype options, the expressions of which may be modulated by the nerve. Primary and secondary myotubes in developing jaw and limb muscles are observed to belong to different categories characterized by different patterns of myosin gene expression. By taking into consideration the pattern of myosins synthesized and the changes in fiber size after denervation, 3 types of primary (fast, slow, and intermediate) fibers can be distinguished in rat fast limb muscles. All primaries synthesize slow myosin soon after their formation, but this is withdrawn in fast and intermediate primaries at different times. After neonatal denervation, slow and intermediate primaries express slow primaries hypertrophy with other fibers atrophy. In the mature rat, the number of slow fibers in the EDL is less than the number of slow primaries. Upon denervation, hypertrophic slow fibers matching the number and topographic distribution of slow primaries appear, suggesting that a subpopulation of the slow primaries acquire the fast phenotype during adult life, but reveal their original identity as slow primaries in response to denervation by hypertrophying and synthesizing slow myosin. It is proposed that within each muscle allotype, the various isotypes of primary and secondary fibers are myogenically determined, and are derived from different lineage of myoblasts

    Undergraduate Nursing Students’ Attitudes Toward Mental Health Nursing

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    Objectives: The purpose of this study was to describe undergraduate nursing students’ attitudes toward mental health nursing and how these attitudes influenced their professional career choices in mental health nursing. Design: A descriptive, online survey was utilized to examine students’ perceptions of mental health nursing. A total of 229 junior and senior nursing students were recruited from eight nursing colleges in Midwestern United States to participate in this survey. Results: Students of different ages, genders, ethnicities, and nursing programs did not report significantly different perceptions of: (a) knowledge of mental illness; (b) negative stereotypes; (c) interest in mental health nursing as a future career; and (d), and beliefs that psychiatric nurses provide a valuable contribution to consumers and the community. Negative stereotypes were significantly different between students who had mental health nursing preparation either in class (p = 0.0147) or in clinical practice (p = 0.0018) and students who had not. There were significant differences in anxiety about mental illness between students who had classes on mental health nursing (p = .0005), clinical experience (p = 0.0035), and work experience in the mental health field (p = 0.0012). Significant differences in an interest in a future career in mental health nursing emerged between students with and without prior mental health experience and between students with and without an interest in an externship program with p-values of 0.0012 and \u3c 0.0001, respectively. Conclusions: The more exposure that students have to mental health nursing through clinical experiences, theory classes, and previous work in the field, the more prepared they feel about caring for persons with mental health issues

    Overexpression of Mcl-1 exacerbates lymphocyte accumulation and autoimmune kidney disease in lpr mice

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    Cell death by apoptosis has a critical role during embryonic development and in maintaining tissue homeostasis. In mammals, there are two converging apoptosis pathways: the ‘extrinsic’ pathway, which is triggered by engagement of cell surface ‘death receptors’ such as Fas/APO-1; and the ‘intrinsic’ pathway, which is triggered by diverse cellular stresses, and is regulated by prosurvival and pro-apoptotic members of the Bcl-2 family of proteins. Pro-survival Mcl-1, which can block activation of the proapoptotic proteins, Bax and Bak, appears critical for the survival and maintenance of multiple haemopoietic cell types. To investigate the impact on haemopoiesis of simultaneously inhibiting both apoptosis pathways, we introduced the vavP-Mcl-1 transgene, which causes overexpression of Mcl-1 protein in all haemopoietic lineages, into Faslpr/lpr mice, which lack functional Fas and are prone to autoimmunity. The combined mutations had a modest impact on myelopoiesis, primarily an increase in the macrophage/monocyte population in Mcl-1tg/lpr mice compared with lpr or Mcl-1tg mice. The impact on lymphopoiesis was striking, with a marked elevation in all major lymphoid subsets, including the non-conventional double-negative (DN) T cells (TCRβ+ CD4– CD8– B220+ ) characteristic of Faslpr/lpr mice. Of note, the onset of autoimmunity was markedly accelerated in Mcl-1tg/lpr mice compared with lpr mice, and this was preceded by an increase in immunoglobulin (Ig)-producing cells and circulating autoantibodies. This degree of impact was surprising, given the relatively mild phenotype conferred by the vavP-Mcl-1 transgene by itself: a two- to threefold elevation of peripheral B and T cells, no significant increase in the non-conventional DN T-cell population and no autoimmune disease. Comparison of the phenotype with that of other susceptible mice suggests that the development of autoimmune disease in Mcl-1tg/lpr mice may be influenced not only by Ig-producing cells but also other haemopoietic cell types

    Dance for Health: the impact of creative dance sessions on older people in an acute hospital setting

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    Background: This service evaluation examined the impact of Dance for Health, a programme of weekly group dance sessions for older patients, which took place on wards in an acute hospital setting. Methods: Qualitative and quantitative observations using the ArtsObs scale were undertaken of 64 dance sessions over a 12-week period involving seven different hospital wards encompassing 313 patient attendances. Results: Statistically significant improvements were observed in the mood of the majority of patients taking part. People engaged mentally and physically with the activity were distracted from their medical condition and from what was happening on the ward. Patients appeared relaxed and were willing to express themselves creatively. Conclusion: The Dance for Health programme had a positive impact on group participants, promoting movement and physical activity for older patients. It is a meaningful and enjoyable activity, which encourages social interaction and provides respite from the medical environment

    Overcoming Barriers to Health and Wellbeing : Community Assets in North East Essex

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    The Overcoming Barriers to Health and Wellbeing report presents research carried out by Public Health and Social Science researchers at Anglia Ruskin University. Colchester Borough Council commissioned this independent study with funding from the North East Essex Health and Wellbeing Alliance. The aim of the research is to provide Local Authorities and health and wellbeing commissioners with insight into the public health benefits of community assets from the perspective of citizens who access them in their local communities. This report provides an evidence-based rationale for the support of community assets to improve the health and wellbeing outcomes of citizens in North East Essex. There is a focus on populations considered to be at increased risk of poor health and wellbeing outcomes, and on addressing populations in places where there are areas of comparative social deprivation in the context of growing health inequalities in the region

    Spot-on: Safe Fuel/Air Compression

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    The emission of fuel vapors into the atmosphere from underground storage tanks at filling stations is a common occurrence in many parts the world. The conditions of the vapor in the tanks vary significantly over a 24 hour period such that evaporation and excess air ingestion during the refueling process can cause tank over pressurization and subsequent emissions. At other times during a 24 hour cycle, pressures can fall below atmospheric pressure. The state of California has recognized this emissions problem and has enacted regulations to address it. Due to these low-emission environmental requirements in California, solutions must be implemented that do not entail release of these vapors into the atmosphere. One solution requires that the vapors fill a balloon during the appropriate times. However, the size of the balloon at typical inflation rates requires a significant amount of physical space (approximately 1000-2000 liters), which may not necessarily be available at filling stations in urban areas. Veeder-Root has a patent pending for a system to compress the vapors that are released to a 10:1 ratio, store this compressed vapor in a small storage tank, and then return the vapors to the original underground fuel tank when the conditions are thermodynamically appropriate (see Figure 1 for the schematic representation of this system). The limitation of the compressor, however, is that the compression phase must take place below the ignition temperature of the vapor. For a 10:1 compression ratio, however, the adiabatic temperature rise of a vapor would be above the ignition temperature. Mathematical modeling is necessary here to estimate the performance of the compressor, and to suggest paths in design for improvement. This report starts with a mathematical formulation of an ideal compressor, and uses the anticipated geometry of the compressor to state a simplified set of partial differential equations. The adiabatic case is then considered, assuming that the temporary storage tank is kept at a constant temperature. Next, the heat transfer from the compression chamber through the compressor walls is incorporated into the model. Finally, we consider the case near the valve wall, which is subject to the maximum temperature rise over the estimated 10,000 cycles that will be necessary for the process to occur. We find that for adiabatic conditions, there is a hot spot close to the wall where the vapor temperature can exceed the wall temperature. Lastly, we discuss the implications of our analysis, and its limitations
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