51 research outputs found

    The Non-Protein Amino Acid BMAA Is Misincorporated into Human Proteins in Place of l-Serine Causing Protein Misfolding and Aggregation

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    Mechanisms of protein misfolding are of increasing interest in the aetiology of neurodegenerative diseases characterized by protein aggregation and tangles including Amyotrophic Lateral Sclerosis (ALS), Alzheimer's disease (AD), Parkinson's disease (PD), Lewy Body Dementia (LBD), and Progressive Supranuclear Palsy (PSP). Some forms of neurodegenerative illness are associated with mutations in genes which control assembly of disease related proteins. For example, the mouse sticky mutation sti, which results in undetected mischarging of tRNAAla with serine resulting in the substitution of serine for alanine in proteins causes cerebellar Purkinje cell loss and ataxia in laboratory animals. Replacement of serine 422 with glutamic acid in tau increases the propensity of tau aggregation associated with neurodegeneration. However, the possibility that environmental factors can trigger abnormal folding in proteins remains relatively unexplored. We here report that a non-protein amino acid, β-N-methylamino-L-alanine (BMAA), can be misincorporated in place of l-serine into human proteins. We also report that this misincorporation can be inhibited by l-serine. Misincorporation of BMAA into human neuroproteins may shed light on putative associations between human exposure to BMAA produced by cyanobacteria and an increased incidence of ALS. © 2013 Dunlop et al

    The Evolution of the Galaxy Rest-Frame Ultraviolet Luminosity Function Over the First Two Billion Years

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    We present a robust measurement and analysis of the rest-frame ultraviolet (UV) luminosity function at z=4-8. We use deep Hubble Space Telescope imaging over the CANDELS/GOODS fields, the Hubble Ultra Deep Field and the Year 1 Hubble Frontier Field deep parallel observations. These surveys provides an effective volume of 0.6-1.2 x 10^6 Mpc^3 over this epoch, allowing us to perform a robust search for faint (M_UV=-18) and bright (M_UV < -21) galaxies. We select candidate galaxies using a well-tested photometric redshift technique with careful screening of contaminants, finding a sample of 7446 galaxies at 3.51000 galaxies at z~6-8. We measure the luminosity function using a Markov Chain Monte Carlo analysis to measure robust uncertainties. At the faint end our results agree with previous studies, yet we find a higher abundance of UV-bright galaxies at z>6, with M* ~ -21 at z>5, different than that inferred based on previous trends at lower redshift. At z=8, a single power-law provides an equally good fit to the UV luminosity function, while at z=6 and 7, an exponential cutoff at the bright-end is moderately preferred. We compare to semi-analytical models, and find that the lack of evolution in M* is consistent with models where the impact of dust attenuation on the bright-end of the luminosity function decreases at higher redshift. We measure the evolution of the cosmic star-formation rate density, correcting for dust attenuation, and find that it declines as (1+z)^(-4.3 +/- 0.5) at z>4, consistent with observations at z>9. Our observations are consistent with a reionization history that starts at z>10, completes at z>6, and reaches a midpoint (x_HII = 0.5) at 6.7<z<9.4. Finally, our observations predict that the abundance of bright z=9 galaxies is likely higher than previous constraints, though consistent with recent estimates of bright z~10 galaxies. [abridged]Comment: Re-submitted to the Astrophysical Journal after first referee's report. 34 pages, 21 figures, 7 tables. The source file includes a machine readable table of our full galaxy sampl

    Tele-Rehabilitation for People with Dementia during the COVID-19 Pandemic: A Case-Study from England

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    ntroduction: The Promoting Activity, Independence and Stability in Early Dementia (PrAISED) is delivering an exercise programme for people with dementia. The Lincolnshire part�nership National Health Service (NHS) foundation Trust successfully delivered PrAISED through a video-calling platform during the Coronavirus Disease 2019 (COVID-19) pandemic. Methods: This qualitative case-study aimed to identify participants that video delivery worked for, to highlight its benefits and its challenges. Interviews were conducted between May and August 2020 with five participants with dementia and their caregivers (n = 10), as well as five therapists from the Lincolnshire partnership NHS foundation Trust. The interviews were analysed through thematic analysis. Results: Video delivery worked best when participants had a supporting caregiver and when therapists showed enthusiasm and had an established rapport with the client. Benefits included time efficiency of sessions, enhancing participants’ motivation, caregivers’ dementia awareness, and therapists’ creativity. Limitations included users’ poor IT skills and resources. Discussion: The COVID-19 pandemic required innovative ways of delivering rehabilitation. This study supports that people with dementia can use tele-rehabilitation, but success is reliant on having a caregiver and an enthusiastic and known therapis

    Promoting activity, independence and stability in early dementia and milk cognitive impairment (PrAISED): randomised controlled trial

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    Objective To determine the effectiveness of an exercise and functional activity therapy intervention in adults with early dementia or mild cognitive impairment compared with usual care. Design Randomised controlled trial. Setting Participants’ homes and communities at five sites in the United Kingdom. Participants 365 adults with early dementia or mild cognitive impairment who were living at home, and family members or carers. Intervention The intervention, Promoting activity, Independence, and Stability in Early Dementia and mild cognitive impairment (PrAISED), was a specially designed, dementia specific, rehabilitation programme focusing on strength, balance, physical activity, and performance of activities of daily living, which was tailored and progressive and addressed risk and the psychological needs of people with dementia. Up to 50 therapy sessions were provided over 12 months. The control group received usual care plus a falls risk assessment. Procedures were adapted during the covid-19 pandemic. Main outcome measures The primary outcome was score on the carer (informant) reported disability assessment for dementia scale 12 months after randomisation. Secondary outcomes were self-reported activities of daily living, physical activity, quality of life, balance, functional mobility, fear of falling, frailty, cognition, mood, carer strain, service use at 12 months, and falls between months 4 and 15. Results 365 patient participants were randomised, 183 to intervention and 182 to control. The median age of participants was 80 years (range 65-95), median Montreal cognitive assessment score was 20 out of 30 (range 13-26), and 58% (n=210) were men. Intervention participants received a median of 31 therapy sessions (interquartile range 22-40) and reported completing a mean 121 minutes of PrAISED exercise each week. Primary outcome data were available for 149 intervention and 141 control participants. Scores on the disability assessment for dementia scale did not differ between groups: adjusted mean difference −1.3, 95% confidence interval −5.2 to 2.6; Cohen’s d effect size −0.06, 95% confidence interval −0.26 to 0.15; P=0.51). Upper 95% confidence intervals excluded small to moderate effects on any of the range of outcome measures. Between months 4 and 15 the intervention group experienced 79 falls and the control group 200 falls (adjusted incidence rate ratio 0.78, 95% confidence interval 0.5 to 1.3; P=0.3). Conclusion The intensive PrAISED programme of exercise and functional activity training did not improve activities of daily living, physical activity, or quality of life; reduce falls; or improve any other secondary health status outcomes, despite good uptake. Future research should consider alternative approaches to maintaining ability and wellbeing in people with dementia

    Symbiotic Futures: Health, Well-being and Care in the Post-Covid World

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    The "Symbiotic Futures: Health, Well-being and Care in the Post-Covid World" project was jointly conceived by the Innovation School at Glasgow School of Art and the Institute of Cancer Sciences at the University of Glasgow. The project partnership involved a community of experts working across both organisations including the University of Glasgow’s new Mazumdar-Shaw Advanced Research Centre (ARC). Future experiences is a collaborative, futures-focused design project where students benefit from the input of a community of experts to design speculative future worlds and experiences based on research within key societal contexts. This iteration of the project asked the students to consider what happens in the Post-Covid landscape ten years from now, where symbiotic experiences of health, well-being and care have evolved to the extent that new forms of medical practice, health communities and cultures of care transform how we interact with each other, with professionals and the world around us. The GSA Innovation School’s final year BDes Product Design students and faculty formed a dynamic community of practice with health, wellbeing and care practitioners and researchers from The University of Glasgow and beyond. This gave the students the opportunity to reflect on the underlying complexities of the future of health, well-being and care, technological acceleration, human agency and quality of life, to envision a 2031 blueprint as a series of six future world exhibits, and design the products, services and system experiences for the people and environments within it. In the first part of the project (Stage 1), Future worlds are groups of students working together on specific topics, to establish the context for their project and collaborate on research and development. In this iteration of Future Experiences, the "Health, Well-being and Care" worlds were clustered together around ‘People focused’ and ‘Environment focused’, but also joined up across these groups to create pairs of worlds, and in the process generate symbiosis between the groups. These worlds were then the starting points which the students explored in their individual projects. The second part of the project (Stage 2) saw individual students select an aspect of their Future World research to develop as a design direction, which they then prototyped and produced as products, services, and/or systems. These are designed for specific communities, contexts or scenarios of use defined by the students to communicate a future experience. These Future experiences reflect the societal contexts explored during the research phase, projected 10 years into the future, and communicated in a manner that makes the themes engaging and accessible. The deposited materials are arranged as follows: 1. Project Landscape Map - A report and blueprint for the project that gives a visual overview of the structure and timeline of the project. 2. Stage one data folders - the data folders for stage one of the project are named after the themes the groups explored to create their Future Worlds. 3. Stage two data folders - the data folders for stage two of the project are named after the individual students who created the project

    Proteolytic defences and the accumulation of oxidized polypeptides in cataractogenesis and atherogenesis

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    Over the last few years, it has been clearly established that normal plasma contains low levels of oxidized polypeptides, and that these accumulate in tissues during several age-related pathologies. In contrast, normal mammalian aging, contrary to conventional dogma, is not clearly associated with enhanced levels of oxidized proteins, except in extracellular connective tissues, whose proteins can, for example, be oxidized by the neutrophil oxidative burst. Since mildly oxidized proteins are susceptible to accelerated degradation in most experimental systems, the question arises as to how the accumulation of oxidized proteins can take place. Such accumulation requires an excess of production (or deposition) over removal, which might reflect alterations in capacity or rate of production or removal. This chapter discusses our presently limited knowledge of rates and control of proteolysis of oxidized proteins in two pathologies, cataractogenesis and atherogenesis. It commences with a brief summary of current understanding of the mechanisms of protein oxidation, and of the observed accumulation of oxidized proteins in several pathologies
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