803 research outputs found

    USPIO-enhanced magnetic resonance imaging of the knee in asymptomatic volunteers

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    The aim of this study was to compare signal characteristics of the synovium in knees of asymptomatic volunteers before and after intravenous administration of ultrasmall superparamagnetic iron oxide particles (USPIO). Ten knees of 10 asymptomatic volunteers were examined before and 36h after intravenous administration of USPIO on a 1.5-T MR system using T1-weighted spin-echo, T2-weighted fast spin-echo, T2*-weighted gradient-echo (GRE), and short inversion time inversion-recovery sequences. In addition, synovial perfusion was measured using Gd-enhanced GRE imaging during the first imaging session. Images were analyzed qualitatively for any visual changes before and after USPIO administration. Signal-to-noise ratios (SNR) of the synovium were determined on unenhanced and USPIO-enhanced sequences. All MR images were reviewed for presence of any degenerative changes. Qualitative image analysis revealed no visually detectable changes of any knee joint before and after USPIO administration. The SNR values of the synovium on T1w, T2w, and T2*w images before and after USPIO administration showed no significant difference (T1, P = 0.86; T2, P = 0.95; T2*, P = 0.86). None of the volunteers showed any relevant degenerative changes of the knee and synovial perfusion was within normal limits. In knees of asymptomatic volunteers without any relevant degenerative changes and normal synovial perfusion neither visual changes nor changes of SNR values of the synovium can be depicted after USPIO administration. This means that USPIO-enhanced MRI may be used for assessment of knee disorders with increased macrophage activit

    Motor and Hippocampal Dependent Spatial Learning and Reference Memory Assessment in a Transgenic Rat Model of Alzheimer\u27s Disease with Stroke

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    Alzheimer\u27s disease (AD) is a debilitating neurodegenerative disease that results in neurodegeneration and memory loss. While age is a major risk factor for AD, stroke has also been implicated as a risk factor and an exacerbating factor. The co-morbidity of stroke and AD results in worsened stroke-related motor control and AD-related cognitive deficits when compared to each condition alone. To model the combined condition of stroke and AD, a novel transgenic rat model of AD, with a mutated form of amyloid precursor protein (a key protein involved in the development of AD) incorporated into its DNA, is given a small unilateral striatal stroke. For a model with the combination of both stroke and AD, behavioral tests that assess stroke-related motor control, locomotion and AD-related cognitive function must be implemented. The cylinder task involves a cost-efficient, multipurpose apparatus that assesses spontaneous forelimb motor use. In this task, a rat is placed in a cylindrical apparatus, where the rat will spontaneously rear and contact the wall of the cylinder with its forelimbs. These contacts are considered forelimb motor use and quantified during video analysis after testing. Another cost-efficient motor task implemented is the beam-walk task, which assesses forelimb control, hindlimb control and locomotion. This task involves a rat walking across a wooden beam allowing for the assessment of limb motor control through analysis of forelimb slips, hindlimb slips and falls. Assessment of learning and memory is completed with Morris water maze for this behavioral paradigm. The protocol starts with spatial learning, whereby the rat locates a stationary hidden platform. After spatial learning, the platform is removed and both short-term and long-term spatial reference memory is assessed. All three of these tasks are sensitive to behavioral differences and completed within 28 days for this model, making this paradigm time-efficient and cost-efficient

    Wohnungslos in der Stadt: Soziologische Perspektiven auf Exklusionsdynamiken im Wechselspiel individueller, raumstruktureller und institutioneller Kontexte

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    Wohnungs- und Obdachlosigkeit gehören zu den prekärsten Ausdrücken von Armut, Marginalisierung und sozialer Exklusion, die von einem vergleichsweise (noch) gut ausgebildeten Sozialstaat einer reichen Industrienation wie Deutschland „eigentlich“ verhindert werden müssten. Die Zahl wohnungsloser Menschen ist seit 2010 jedoch angestiegen. Daher stellt sich die Frage nach den Gründen. Der vorliegende Beitrag fokussiert die Wechselwirkungen individueller, institutioneller und raumstruktureller Kontexte bei der Entstehung und Verfestigung von Wohnungs- und Obdachlosigkeit. Im Mittelpunkt steht die Herausarbeitung einer Heuristik, mit Hilfe derer Bedingungen identifiziert werden, die sich für das Auftreten von Wohnungsnotfällen als ausschlaggebend erweisen können. Anhand des empirischen Falls einer mittelgroßen Universitätsstadt sollen die intendierten wie nicht-intendierten Mechanismen des (partiellen) Ausschlusses von sozialstaatlichen Leistungen auf kommunaler Ebene identifiziert werden, stets unter der Berücksichtigung der individuellen Dispositionen und Biographien, der kommunalen (Regulierungs-)Praktiken sowie des faktischen Versagens (gesamt-)staatlicher wie marktlicher Rahmenbedingungen

    The effects of different saddle pads on the pressure exerted on the equine back by correctly fitting dressage saddles

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    In order to improve saddle fit and comfort for the horse, many equestrians use a saddle pad in addition to an ordinary saddle cloth or blanket. To date, only a few scientific studies have investigated if such pads lower the magnitude of pressure exerted on the horse’s back. The results of these studies are highly variable, presumably due to the different materials of the examined pads. The present study investigated the effect of five different, commercially available saddle pads on the mean pressure, the highest mean pressure, and the loaded area below the saddle, as well as the range of motion (ROM) of the centre of pressure (COP) on the horse’s back. Electronic saddle pressure measurements were carried out with eight horses ridden by the same person, using five different pads and a thin saddle cloth as control. Saddle pressure measurements were carried out at all gaits and on both reins, using the Pliance -S system (Novel). The results revealed that all tested pads except for the gel pad significantly lowered mean pressure below the saddle (range in reduction: 0.8 to 1.8 kPA) as well as in areas with the highest mean pressure, representing pressure points (range: 2.1 to 5.8 kPA). None of the pads increased pressure. The loaded area below the saddle was decreased slightly, but not significantly, when pads were used. The effect of the pads on the ROM of the COP was inconsistent; certain pads significantly increased this variable, but only at certain gaits. This may indicate a loss of stability in the horse-rider system, but if the magnitude of the observed changes is relevant needs further investigation. The results indicate that none of the investigated pads affected mean pressure in an unfavourable way and that the thicker pads may help to reduce the pressure acting on the horse’s back

    Findings and interobserver agreement in radiography and ultrasonography of the vertebral column of a large population of normally performing horses

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    Diagnostic imaging is a mainstay in the investigation of equine neck and back pain, but interpretation of radiographic and ultrasonographic findings in the spinal column of horses is not straightforward for a variety of reasons including individual anatomical variations, progressive degenerative nature of most pathologies and superimposition as well as technical limits. These issues are even more relevant in the context of examinations of apparently sound horses with absent, mild or unclear complaints, like it is often the case in pre-purchase examinations or cases of failure to meet expected performance. The first aim was to report on the spectrum, degree and location of first-line imaging findings in the spine of a large population of normally performing horses. Limited data is available about agreement of interpretation of equine vertebral column imaging by radiologists. The second aim of this prospective study was to determine interobserver agreement on radiographic and ultrasonographic diagnostic imaging findings in the vertebral column of the same population between multiple observers with longstanding experience in equine diagnostic imaging at two different institutions. Seventy-one horses randomly selected from a larger population of 250 normally performing horses participating in a swiss project on equine back health were examined at one referral center. Radiographic and ultrasonographic examinations were performed in a standardized fashion and images graded separately by two experienced radiologists at two different institutions. Focus was placed on osteoarthrosis of the synovial intervertebral articulations (SIVAs), impinging and overriding of the spinous processes (SPs) and spondylosis. Cohen’s weighted kappa was calculated for each pathology, location and segment in each modality. Interobserver agreement was calculated for findings at specific locations, single pathologies and single grades. Most horses showed no changes and were allocated grades 0 at most locations. Few abnormalities were found throughout the vertebral column, with clusters of abnormalities of the SIVAs in the caudal cervical segment and cranial lumbar segment as well as a cumulation of changes at the dorsal spinous processes in the caudal thoracic segment. These coincide with previously reported predilection sites of imaging findings in symptomatic populations. Overall mean value of agreement for imaging findings was moderate (k= 0.7). Agreement was moderate for imaging findings regarding the synovial intervertebral articulations of the thoracolumbar spine in radiography (k=0.66) but weak in ultrasonography (k=0.58). There was moderate agreement in the imaging findings of the cervical spine in ultrasonography (k=0.61) as well as radiography (k=0.62). Strong agreement was found in the radiographic assessment of changes of the thoracolumbar spinous processes (k=0.80). Almost perfect agreement was found in the radiographic assessment of thoracolumbar spondylosis (k=0.95). Agreement between radiologists in detection and grading of pathologies of the equine vertebral column is weak to almost perfect depending on pathology and location. Our results confirm findings about distribution of specific pathologies found in other studies and support the importance of interpreting imaging findings along with clinical findings for definitive case management and decision making. Additional studies are needed for determination of the correlation of imaging findings among different modalities and correlation of diagnostic imaging with clinical findings

    The contested and contingent outcomes of Thatcherism in the UK

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    The death of Margaret Thatcher in April 2013 sparked a range of discussions and debates about the significance of her period in office and the political project to which she gave her name: Thatcherism. This article argues that Thatcherism is best understood as a symbolically important part of the emergence of first-phase neoliberalism. It engages with contemporary debates about Thatcherism among Marxist commentators and suggests that several apparently divergent positions can help us now reach a more useful analysis of Thatcherism’s short- and long-term outcomes for British political economy. The outcomes identified include: an initial crisis in the neoliberal project in the UK; the transformation of the party political system to be reflective of the politics of neoliberalism, rather than its contestation; long-term attempts at the inculcation of the neoliberal individual; de-industrialisation and financial sector dependence; and a fractured and partially unconscious working class. In all long-term outcomes, the contribution of Thatcherism is best understood as partial and largely negative, in that it cleared the way for a longer-term and more constructive attempt to embed neoliberal political economy. The paper concludes by suggesting that this analysis can inform current debates on the left of British politics about how to oppose and challenge the imposition of neoliberal discipline today
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