6,555 research outputs found

    The effects of peptide modified gellan gum and olfactory ensheathing glia cells on neural stem/progenitor cell fate

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    The regenerative capacity of injured adult central nervous system (CNS) tissue is very limited. Specifically, traumatic spinal cord injury (SCI) leads to permanent loss of motor and sensory functions below the site of injury, as well as other detrimental complications. A potential regenerative strategy is stem cell transplantation; however, cell survival is typically less than 1%. To improve cell survival, stem cells can be delivered in a biomaterial matrix that provides an environment conducive to survival after transplantation. One major challenge in this approach is to define the biomaterial and cell strategies in vitro. To this end, we investigated both peptide-modification of gellan gum and olfactory ensheathing glia (OEG) on neural stem/progenitor cell (NSPC) fate. To enhance cell adhesion, the gellan gum (GG) was modified using Diels–Alder click chemistry with a fibronectin-derived synthetic peptide (GRGDS). Amino acid analysis demonstrated that approximately 300 nmol of GRGDS was immobilized to each mg of GG. The GG–GRGDS had a profound effect on NSPC morphology and proliferation, distinct from that of NSPCs in GG alone, demonstrating the importance of GRGDS for cell-GG interaction. To further enhance NSPC survival and outgrowth, they were cultured with OEG. Here NSPCs interacted extensively with OEG, demonstrating significantly greater survival and proliferation relative to monocultures of NSPCs. These results suggest that this co-culture strategy of NSPCs with OEG may have therapeutic benefit for SCI repair.: Fundação para a Ciência e a Tecnologia (FCT) - SFRH/BD/40684/2007, Science 2007 Programe, PTDC/SAU-BMA/114059/2009).Ontario Ministry of Research and Innovation (Ontario Neurotrauma FoundationCanadian Institute of Health Research (MSS)Stem Cell Network (MJC

    An integrated approach of building information modelling and life cycle assessment (BIM-LCA) for gas and solar water heating systems

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    Buildings are responsible for the energetic consumption and potential greenhouse gas emissions during their life cycle. Water heating system contribute to a building’s energetic consumption, mainly in residential units, throughout the building’s operational phase. Variability in energy sources, reservation and distribution systems of hot water along with the types of construction materials used in these building systems are key decisions to make in the initial design phases of a building project. Often, the definition of the most appropriate water heating system for a building is made via a technical-economic decision. However, the decision is rarely based on natural resource consumption and environmental impact generation throughout the life-cycle of the heating systems and of buildings as a whole. This study presents an application of a specific environmental management tool, based on an integrated Building Information Modelling (BIM) and Life-Cycle Analysis (LCA) method for selection of hot water systems, during the early design building phase. The proposed approach is implemented in the pre-operational phase, in order to enable decision makers to appreciate the resulting environmental performance of water heating systems in buildings. The applicability of the framework is tested via a comparative study of solar heating water systems and natural gas heating water systems for a residential multifamily building to be constructed in Rio de Janeiro, Brazil. For the indicators damage to human health and damage to ecosystem, results indicate that the greatest impact on global warming comes from the natural gas heating system, while for solar heating, free particulate matter was the highest negative contribution. The operation phase for the natural gas system was highest for climate change while for solar heating system, it was the fresh water that was impacted the most during the pre-operational phase of the system’s use

    Esclerosis sistémica cutáneo limitada: un reporte de caso

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    La esclerosis sistémica es una enfermedad multisistémica caracterizada por disfunción vascular generalizada y fibrosis progresiva de la piel y órganos internos. Dos subconjuntos clínicos distintos se reconocen tradicionalmente en función del grado de afectación de piel: esclerodermia sistémica cutánea limitada y cutánea difusa. Reportamos el caso de un paciente de 52 años con rasgos del síndrome de CREST, tos no productiva, disfonía y pérdida de peso. Al examen físico presenta piel engrosada y tensa en las partes distales de sus extremidades, esclerodactilia, calcinosis cutis, telangiectasias y microstomía. En exámenes auxiliares se encontró fibrosis pulmonar en tomografía computarizada de tórax, esofagitis a la endoscopía, parálisis de cuerda vocal con laringoscopía y anti Scl-70 positivo. Debido a que no es una enfermedad frecuente, los autores decidieron realizar el presente reporte para compartir estos hallazgos con la comunidad médica.Palabras clave: Esclerodermia Sistémica , Síndrome CREST , Fibrosis Pulmonar

    Thinking Through our Processes: How the UCSC Community Psychology Research & Action Team Strives to Embody Ethical, Critically Reflexive Anti-racist Feminist Praxis

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    Co-written by eight people, this paper describes how the UCSC Community Psychology Research and Action Team (CPRAT) organizes itself in weekly group meetings and how this structure is an attempt to embody an ethical, critically reflexive anti-racist feminist praxis. First, we outline the community psychology core competency of an ethical, reflective practice (Dalton & Wolfe, 2012). We offer a friendly amendment to consider an ethical, critically reflexive anti-racist feminist praxis. Second, we discuss how we organize CPRAT meetings to uphold these ideas. We describe our current structure, which includes personal and project check-ins, rotating facilitation, and attention to broader professional development issues. Third, we provide two examples to illustrate our process: (a) why talking about poop matters in addressing imposter syndrome and (b) getting our team on the same page regarding a research site. We end the paper with a description of a “rough edge,” or an area for growth in our praxis

    Investigation using whole genome sequencing of a prolonged restaurant outbreak of Salmonella typhimurium linked to the building drainage system, England, February 2015 to March 2016

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    Following notification of a Salmonella enterica serovar Typhimurium gastroenteritis outbreak, we identified 82 cases linked to a restaurant with symptom onset from 12 February 2015 to 8 March 2016. Seventy-two cases had an isolate matching the nationally unique whole genome sequencing profile (single nucleotide polymorphism (SNP) address: 1.1.1.124.395.395). Interviews established exposure to the restaurant and subsequent case-control analysis identified an association with eating carvery buffet food (adjusted odds ratios (AOR): 20.9; 95% confidence interval (CI): 2.2 - infinity). Environmental inspections, food/water testing, and a food trace-back investigation were inconclusive. Repeated cycles of cleaning were undertaken, including hydrogen peroxide fogging, however, transmission continued. After 7 months of investigation, environmental swabbing identified 106 isolates from kitchen surfaces and restaurant drains matching the outbreak profile. We found structural faults with the drainage system and hypothesised that a reservoir of bacteria in drain biofilm and underfloor flooded areas may have sustained this outbreak. Ineffective drain water-traps (U-bends) may have also contributed by allowing transmission of contaminated aerosols into the kitchen environment. These findings suggest that routine swabbing of sink drain points and inspection of drainage systems should be considered in future outbreak scenarios

    Modulation of bone marrow mesenchymal stem cell secretome by ECM-like hydrogels

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    It has been demonstrated that bone marrow mesenchymal stem cell (BM-MSCs) transplantation has beneficial effects on several central nervous system (CNS) debilitating conditions. Growing evidence indicate that trophic factors secreted by these cells are the key mechanism by which they are acting. These cells are frequently used in combination with 3D artificial matrices, for instance hydrogels, in tissue engineering-based approaches. However, so far, no study has been reported on the influence of such matrices, namely the presence or absence of extracellular matrix motifs, on BM-MSCs secretome and its effects in neuronal cell populations. In this sense, we herein studied the impact of a hydrogel, gellan gum, on the behavior and secretome of BM-MSCs, both in its commercial available form (commonly used in tissue engineering) and in a fibronectin peptide-modified form. The results showed that in the presence of a peptide in the gellan gum hydrogel, BM-MSCs presented higher proliferation and metabolic activity than in the regular hydrogel. Moreover, the typical spindle shape morphology of BM-MSCs was only observed in the modified hydrogel. The effects of the secretome of BM-MSCs were also affected by the chemical nature of the extracellular matrix. BM-MSCs cultured in the modified hydrogel were able to secrete factors that induced higher metabolic viabilities and neuronal cell densities, when compared to those of the unmodified hydrogel. Thus adding a peptide sequence to the gellan gum had a significant effect on the morphology, activity, proliferation and secretome of BM-MSCs. These results highlight the importance of mimicking the extracellular matrix when BM-MSCs are cultured in hydrogels for CNS applications.We would like to acknowledge the funds attributed by the Portuguese Foundation for Science and Technology (FCT) (Grant No PTDC/SAU-BMA/114059/2009; pre-doctoral fellowships to N.A. Silva, SFRH/BD/40684/2007; Ciencia 2007 Program to A.J. Salgado; PEst-C/SAU/LA0001/2013-2014 and RNEM-REDE/1506/REM/2005). This work was partially funded by EU-FP7-Health-2011-Collaborative Project 278612, Biohybrid Templates for Peripheral Nerve Regeneration, and co-funded by Programa Operacional Regional do Norte (ON.2 - O Novo Norte), ao abrigo do Quadro de Referencia Estrategico Nacional (QREN), atraves do Fundo Europeu de Desenvolvimento Regional (FEDER)

    Science paper or big data? Assessing invasion dynamics using observational data

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    Non-native species are spreading at an unprecedented rate over large spatial scales, with global environmental change and growth in commerce providing novel opportunities for range expansion. Assessing the pattern and rate of spread is key to the development of strategies for safeguarding against future invasions and efficiently managing existing ones. Such assessments often depend on spatial distribution data from online repositories, which can be spatially biased, imprecise, and lacking in quantity. Here, the influence of disparities between occurrence records from online data repositories and what is known of the invasion history from peer-reviewed published literature on non-native species range expansion was evaluated using 6693 records of the Pacific oyster, Magallana gigas(Thunberg, 1793), spanning 56 years of its invasion in Europe. Two measures of spread were calculated: maximum rate of spread (distance from introduction site over time) and accumulated area (spatial expansion). Results suggest that despite discrepancies between online and peer-reviewed data sources, including a paucity of records from the early invasion history in online repositories, the use of either source does not result in significantly different estimates of spread. Our study significantly improves our understanding of the European distribution of M. gigas and suggests that a combination of short- and long-range dispersal drives range expansions. More widely, our approach provides a framework for comparison of online occurrence records and invasion histories as documented in the peer-reviewed literature, allowing critical evaluation of both data sources and improving our understanding of invasion dynamics significantly

    Metallic tube type energy absorbers: a synopsis

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    This paper presents an overview of energy absorbers in the form of tubes in which the material used is predominantly mild steel and/or aluminium. A brief summary is also made of frusta type energy absorbers. The common modes of deformation such as lateral and axial compression, indentation and inversion are reviewed. Theoretical, numerical and experimental methods which help to understand the behaviour of such devices under various loading conditions are outlined. Although other forms of energy absorbing materials and structures exist such as composites and honeycombs, this is deemed outside the scope of this review. However, a brief description will be given on these materials. It is hoped that this work will provide a useful platform for researchers and design engineers to gain a useful insight into the progress made over the last few decades in the field of tube type energy absorbers

    Consumption patterns of sweet drinks in a population of Australian children and adolescents (2003–2008)

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    <p>Abstract</p> <p>Background</p> <p>Intake of sweet drinks has previously been associated with the development of overweight and obesity among children and adolescents. The present study aimed to assess the consumption pattern of sweet drinks in a population of children and adolescents in Victoria, Australia.</p> <p>Methods</p> <p>Data on 1,604 children and adolescents (4–18 years) from the comparison groups of two quasi-experimental intervention studies from Victoria, Australia were analysed<it>.</it> Sweet drink consumption (soft drink and fruit juice/cordial) was assessed as one day’s intake and typical intake over the last week or month at two time points between 2003 and 2008 (mean time between measurement: 2.2 years).</p> <p>Results</p> <p>Assessed using dietary recalls, more than 70% of the children and adolescents consumed sweet drinks, with no difference between age groups (p = 0.28). The median intake among consumers was 500 ml and almost a third consumed more than 750 ml per day. More children and adolescents consumed fruit juice/cordial (69%) than soft drink (33%) (p < 0.0001) and in larger volumes (median intake fruit juice/cordial: 500 ml and soft drink: 375 ml). Secular changes in sweet drink consumption were observed with a lower proportion of children and adolescents consuming sweet drinks at time 2 compared to time 1 (significant for age group 8 to <10 years, p = 0.001).</p> <p>Conclusion</p> <p>The proportion of Australian children and adolescents from the state of Victoria consuming sweet drinks has been stable or decreasing, although a high proportion of this sample consumed sweet drinks, especially fruit juice/cordial at both time points.</p
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