593 research outputs found

    Endogenous transforming growth factor Ī²1 suppresses inflammation and promotes survival in adult CNS

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    Transforming growth factor Ī²1 (TGFĪ²1) is a pleiotropic cytokine with potent neurotrophic and immunosuppressive properties that is upregulated after injury, but also expressed in the normal nervous system. In the current study, we examined the regulation of TGFĪ²1 and the effects of TGFĪ²1 deletion on cellular response in the uninjured adult brain and in the injured and regenerating facial motor nucleus. To avoid lethal autoimmune inflammation within 3 weeks after birth in TGFĪ²1-deficient mice, this study was performed on a T- and B-cell-deficient RAG2-/- background. Compared with wild-type siblings, homozygous deletion of TGFĪ²1 resulted in an extensive inflammatory response in otherwise uninjured brain parenchyma. Astrocytes increased in GFAP and CD44 immunoreactivity; microglia showed proliferative activity, expression of phagocytosis-associated markers [Ī±XĪ²2, B7.2, and MHC1 (major histocompatibility complex type 1)], and reduced branching. Ultrastructural analysis revealed focal blockade of axonal transport, perinodal damming of axonal organelles, focal demyelination, and myelin debris in granule-rich, phagocytic microglia. After facial axotomy, absence of TGFĪ²1 led to a fourfold increase in neuronal cell death (52 vs 13%), decreased central axonal sprouting, and significant delay in functional recovery. It also interfered with the microglial response, resulting in a diminished expression of early activation markers [ICAM1 (intercellular adhesion molecule 1), Ī±6Ī²1, and Ī±MĪ²2] and reduced proliferation. In line with axonal and glial findings in the otherwise uninjured CNS, absence of endogenous TGFĪ²1 also caused an āˆ¼10% reduction in the number of normal motoneurons, pointing to an ongoing and potent trophic role of this anti-inflammatory cytokine in the normal as well as in the injured brain. Copyright Ā© 2007 Society for Neuroscience

    The Management of Talar Osteochondral Lesions - Current Concepts

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    Osteochondral lesions of the talus (OLTs) are a common complication following trauma, involving both the articular cartilage and the underlying subchondral bone, with variable aetiologies and often presenting with non-specific symptoms. Diagnosis of OLTs requires a combination of clinical assessment and imaging and despite many different treatment options, there is no generalised consensus regarding which option is the most effective. Left untreated, OLTs risk progressing to osteoarthritis. Acute non-displaced OLTs can be treated non-operatively. However, OLTs refractory to non-surgical care for three to six months may be suitable for surgical care. In these cases, conservative treatments are often unsuccessful, particularly for larger and more severe defects and so the majority require surgical intervention. Although bone marrow stimulation techniques remain the ā€œgold standardā€ for lesions <150 mm2, there still requires a need for better long term clinical data and cost-benefit analyses compared with other treatment options. Biological attempts at either regenerating or replacing the articular cartilage are however demonstrating some promising results, but each with their own advantages and disadvantages. In this review, we summarise the clinical management of OLTs and present the current concepts of different treatment regimes

    Chemical tools for study of phosphohistidine: generation of Ā selective Ī¤ā€phosphohistidine and Ī ā€phosphohistidine antibodies

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    Non-hydrolysable stable analogues of Ļ„-phosphohistidine (Ļ„-pHis) and Ļ€-pHis have been designed aided by electrostatic surface potential calculations, and subsequently synthesized. The Ļ„-pHis and Ļ€-pHis analogues (phosphopyrazole 8 and pyridyl amino amide 13, respectively) were used as haptens to generate pHis polyclonal antibodies. Both Ļ„-pHis and Ļ€-pHis conjugates in the form of a BSA-glutaraldehyde-Ļ„-pHis and BSA-glutaraldehyde-Ļ€-pHis were synthesized and characterized by 31P NMR spectroscopy. Commercially available Ļ„-pHis (SC56-2) and Ļ€-pHis (SC1-1; SC50-3) monoclonal antibodies were used to show that the BSA-G-Ļ„-pHis and BSA-G-Ļ€-pHis conjugates could be used to assess the selectivity of pHis antibodies in a competitive ELISA. Subsequently, the selectivity of the generated pHis antibodies generated using phosphopyrazole 8 and pyridyl amino amide 13 as haptens was assessed by competitive ELISA against His, pSer, pThr, pTyr, Ļ„-pHis and Ļ€-pHis. Antibodies generated using the phosphopyrazole 8 as a hapten were found to be selective for Ļ„-pHis, and antibodies generated using the pyridyl amino amide 13 were found to be selective for Ļ€-pHis. Both Ļ„- and Ļ€-pHis antibodies were shown to be effective in immunological experiments, including ELISA, western blot, and immunofluorescence. The Ļ„-pHis antibody was also shown to be useful in the immunoprecipitation of proteins containing pHis

    Evaluation of AllergiSense smartphone tools for adrenaline injection training

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    Ā© 2015 IEEE. Anaphylaxis is an increasingly prevalent life-threatening allergic condition that requires people with anaphylaxis and their caregivers to be trained in the avoidance of allergen triggers and in the administration of adrenaline auto-injectors. The prompt and correct administration of auto-injectors in the event of an anaphylactic reaction is a significant challenge in the management of anaphylaxis. Unfortunately, many people do not know how to use auto-injectors and either fail to use them or fail to use them correctly. This is due in part to deficiencies in training and also to the lack of a system encouraging continuous practice with feedback. Assistive smartphone healthcare technologies have demonstrated potential to support the management of chronic conditions such as diabetes and cardiovascular disease, but there have been deficiencies in their evaluation and there has been a lack of application to anaphylaxis. This paper describes AllergiSense, a smartphone app and sensing system for anaphylaxis management, and presents the results of a randomized, controlled, pre-post evaluation of AllergiSense injection training and feedback tools with healthy participants. Participants whose training was supplemented with AllergiSense injection feedback achieved significantly better practiced injections with 90.5% performing correct injections compared to only 28.6% in the paper-only control group. In addition, the results provide insights into possible self-efficacy failings in traditional training and the benefits of embedding self-efficacy theory into the technology design process

    Determinants of outcome in operatively and non-operatively treated Weber-B ankle fractures

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    Introduction: Treatment of ankle fractures is often based on fracture type and surgeon's individual judgment. Literature concerning the treatment options and outcome are dated and frequently contradicting. The aim of this study was to determine the clinical and functional outcome after AO-Weber B-type ankle fractures in operatively and conservatively treated patients and to determine which factors influenced outcome. Patients and methods: A retrospective cohort study in patients with a AO-Weber B-type ankle fracture. Patient, fracture and treatment characteristics were recorded. Clinical and functional outcome was measured using the Olerud-Molander Ankle Score (OMAS), the American Orthopaedic Foot and Ankle Society ankle-hindfoot score (AOFAS) and a Visual Analog Score (VAS) for overall satisfaction (range 0-10). Results: Eighty-two patients were treated conservatively and 103 underwent operative treatment. The majority was female. Most conservatively treated fractures were AO-Weber B1.1 type fractures. Fractures with fibular displacement (mainly AO type B1.2 and Lauge-Hansen type SER-4) were predominantly treated operatively. The outcome scores in the non-operative group were OMAS 93, AOFAS 98, and VAS 8. Outcome in this group was independently negatively affected by age, affected side, BMI, fibular displacement, and duration of plaster immobilization. In the surgically treated group, the OMAS, AOFAS, and VAS scores were 90, 97, and 8, respectively, with outcome negatively influenced by duration of plaster immobilization. Conclusion: Treatment selection based upon stability and surgeon's judgment led to overall good clinical outcome in both treatment groups. Reducing the cast immobilization period may further improve outcome

    Assessing the life cycle environmental impacts of titania nanoparticle production by continuous flow solvo/hydrothermal synthesis

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    Continuous-flow hydrothermal and solvothermal syntheses offer substantial advantages over conventional processes, producing high quality materials from a wide range of precursors. In this study, we evaluate the ā€œcradle-to-gateā€ life cycle environmental impacts of alternative titanium dioxide (TiOā‚‚) nanoparticle production parameters, considering a range of operational conditions, precursors, material properties and production capacities. A detailed characterisation of the nano-TiOā‚‚ products allows us, for the first time, to link key nanoparticle characteristics to production parameters and environmental impacts, providing a useful foundation for future studies evaluating nano-TiOā‚‚ applications. Five different titanium precursors are considered, ranging from simple inorganic precursors, like titanium oxysulphate (TiOS), to complex organic precursors such as titanium bis(ammonium-lactato)dihydroxide (TiBALD). Synthesis at the laboratory scale is used to determine the yield, size distribution, crystallinity and phase of the nanoparticles. The specifications and operating experience of a full scale plant (>1000 t per year) are used to estimate the mass and energy inputs of industrial scale production for the life cycle assessment. Overall, higher process temperatures are linked to larger, more crystalline nanoparticles and higher conversion rates. Precursor selection also influences nano-TiOā‚‚ properties: production from TiOS results in the largest particle sizes, while TiBALD achieves the smallest particles and narrowest size distribution. Precursor selection is the main factor in determining cradle-to-gate environmental impacts (>80% in some cases), due to the production impact of complex organic precursors. Nano-TiO2 production from TiOS shows the lowest global warming potential (GWP) (<12 kg COā‚‚-eq. per kg TiOā‚‚) and cumulative energy demand (CED) (<149 MJ kgĀÆĀ¹ TiOā‚‚) due to the low environmental impact of the precursor, the use of water as a solvent and its high yield even at lower temperatures. Conversely, the TiBALD precursor shows the highest impact (86 kg COā‚‚-eq. per kg TiOā‚‚ and 1952 MJ kgĀÆĀ¹ TiOā‚‚) due to the need for additional post-synthesis steps and complexity of precursor manufacturing. The main purpose of this study is not a direct comparison of the environmental impacts of TiOā‚‚ nanoparticles manufactured utilizing various precursors under different conditions, but to provide an essential foundation for future work evaluating potential applications of nano-TiOā‚‚ and their life cycle environmental impacts

    Dangers of using the edges of the Brillouin zone

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    International audienceIn solid-state physics, including photonics and wherever periodic lattice structures occur, it is essential to establish the fundamental features associated with wave propagation through the lattice: This is achieved using Bloch waves, the reciprocal lattice, and the reduction, using periodicity, to consider the irreducible Brillouin zone. A general approach, although widely accepted as not being perfectly legitimate, is to plot the dispersion relations around the edges of the Brillouin zone. We show definitively that this can be dangerous and that an important mode of practical significance is missed if this is done in too cavalier a fashion: This missing mode is illustrated for the design of endoscopes based on spring-mass (discrete) periodic structures and photonic crystals
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