4,651 research outputs found

    The foreign body reaction in total hip arthroplasties. A correlated light-microscopy, SEM, and TEM study.

    Get PDF
    An in vivo histological and ultrastructural study of the cellular reaction to particulate material currently used in orthopaedic surgery produced evidence that, on a strictly cellular level, the main damage is done by the smallest particles produced by hip prostheses, i.e. metal particles, irrespective of differences in their chemical composition. Particle size and release rate are the critical factors, although other mechanisms of cellular damage may be active once granulation tissue is formed

    Involvement of metal particles in loosening of metal-plastic total hip prostheses.

    Get PDF
    Four loosened metal-on-plastic total hip prostheses and associated tissues were examined. Each implant showed an uncommonly high formation of metal particles produced by wear or corrosion of the femoral stem. The granulation tissue between bone and cement was characterized by macrophages containing metal particles. Histological, histochemical, and ultrastructural investigations have been performed to assess cellular reactions to ingested metal particles. Pathogenesis of loosening in these cases is discussed in relation to the role of macrophages in bone resorption

    Identity, reputation and social interaction with an application to sequential voting

    Get PDF
    We analyze binary choices in a random utility model assuming that the agent's preferences are affected by conformism (with respect to the behavior of the society) and coherence (with respect to his identity). We apply the analysis to sequential voting when voters like to win

    RCAN1.4 regulates VEGFR-2 internalisation, cell polarity and migration in human microvascular endothelial cells

    Get PDF
    Regulator of calcineurin 1 (RCAN1) is an endogenous inhibitor of the calcineurin pathway in cells. It is expressed as two isoforms in vertebrates: RCAN1.1 is constitutively expressed in most tissues, whereas transcription of RCAN1.4 is induced by several stimuli that activate the calcineurin-NFAT pathway. RCAN1.4 is highly upregulated in response to VEGF in human endothelial cells in contrast to RCAN1.1 and is essential for efficient endothelial cell migration and tubular morphogenesis. Here, we show that RCAN1.4 has a role in the regulation of agonist-stimulated VEGFR-2 internalisation and establishment of endothelial cell polarity. siRNA-mediated gene silencing revealed that RCAN1 plays a vital role in regulating VEGF-mediated cytoskeletal reorganisation and directed cell migration and sprouting angiogenesis. Adenoviral-mediated overexpression of RCAN1.4 resulted in increased endothelial cell migration. Antisense-mediated morpholino silencing of the zebrafish RCAN1.4 orthologue revealed a disrupted vascular development further confirming a role for the RCAN1.4 isoform in regulating vascular endothelial cell physiology. Our data suggest that RCAN1.4 plays a novel role in regulating endothelial cell migration by establishing endothelial cell polarity in response to VEGF

    EvoBot: Towards a Robot-Chemostat for Culturing and Maintaining Microbial Fuel Cells (MFCs)

    Get PDF
    In this paper we present EvoBot, a RepRap open-source 3D-printer modified to operate like a robot for culturing and maintaining Microbial Fuel Cells (MFCs). EvoBot is a modular liquid handling robot that has been adapted to host MFCs in its experimental layer, gather data from the MFCs and react on the set thresholds based on a feedback loop. This type of robot-MFC interaction, based on the feedback loop mechanism, will enable us to study further the adaptability and stability of these systems. To date, EvoBot has automated the nurturing process of MFCs with the aim of controlling liquid delivery, which is akin to a chemostat. The chemostat is a well-known microbiology method for culturing bacterial cells under controlled conditions with continuous nutrient supply. EvoBot is perhaps the first pioneering attempt at functionalizing the 3D printing technology by combining it with the chemostat methods. In this paper, we will explore the experiments that EvoBot has carried out so far and how the platform has been optimised over the past two years

    Evaluation of a breathing retraining intervention to improve quality of life in asthma: quantitative process analysis of the BREATHE randomised controlled trial

    Get PDF
    Objective: Explore group differences between interventions (DVD and booklet (DVDB) versus face-to-face and booklet (F2FB), versus usual care) in the BREATHE trial of breathing retraining for asthma. Design: Quantitative process analysis exploring group expectancy, experience and practice before and after intervention delivery for the main trial. Setting: Primary care subjects: Adults with asthma (DVDB n = 261; F2FB n = 132). Main measures: Baseline - expectancy about breathing retraining; Follow-up 3, 6 and 12 months - self-efficacy, treatment experience (enjoyment of treatment, perceptions of physiotherapist, perceptions of barriers), amount of practice (weeks, days/week, times/day), continued practice; All time points - anxiety (Hospital Anxiety and Depression Scale), asthma QoL (Asthma Quality of Life Questionnaire). Results: No group differences in baseline expectancy. Statistically significant results (p<0.05) indicated that: At follow-up F2FB participants perceived greater need for a physiotherapist than DVDB participants (3.43 (0.87) versus 2.15 (1.26)). F2FB participants reported greater enjoyment of core techniques (such as stomach breathing 7.42(1.67) versus 6.13 (1.99) (DVDB)). Fewer F2FB participants reported problems due to doubts (24 (22.9%) versus 90 (54.2%). F2FB participants completed more practice sessions (75.01 (46.38) versus 48.56 (44.71)). Amount of practice was not significantly related to QoL. In the DVDB arm, greater confidence in breathing retraining ability explained 3.9% of variance in QoL at 12 months. Conclusions: Adults with asthma receiving breathing retraining face-to-face report greater enjoyment and undertaking more practice than those receiving a DVD and booklet, but practice is not related to QoL. Greater confidence in ability to do breathing retraining is associated with improved QoL

    Results of the British Society of Gastroenterology supporting women in gastroenterology mentoring scheme pilot.

    Get PDF
    Introduction: Mentorship has long been recognised as beneficial in the business world and has more recently been endorsed by medical and academic professional bodies. Recruitment of women into gastroenterology and leadership roles has traditionally been difficult. The Supporting Women in Gastroenterology network developed this pilot scheme for female gastroenterologists 5 years either side of the Completion Certificate of Specialist Training (CCST) to examine the role that mentorship could play in improving this discrepancy. Method: Female gastroenterology trainees and consultant gastroenterologists within 5 years either side of CCST were invited to participate as mentees. Consultant gastroenterologists of both genders were invited to become mentors. 35 pairs of mentor:mentees were matched and completed the scheme over 1 year. Training was provided. Results: The majority of the mentees found the sessions useful (82%) and enjoyable (77%), with the benefit of having time and space to discuss professional or personal challenges with a gastroenterologist who is not a colleague. In the longitudinal study of job satisfaction, work engagement, burnout, resilience, self-efficacy, self-compassion and work-life balance, burnout scale showed a small but non significant improvement over the year (probably an effect of small sample size). Personal accomplishment improved significantly. The main challenges were geography, available time to meet and pair matching. The majority of mentors surveyed found the scheme effective, satisfying, mutually beneficial (70%) and enjoyable (78%). Conclusion: Mentorship is shown to be beneficial despite the challenges and is likely to improve the recruitment and retention of women into gastroenterology and leadership roles, but is likely to benefit gastroenterologists of both genders

    Adiposity, obesity, and arterial aging: longitudinal study of aortic stiffness in the Whitehall II cohort

    Get PDF
    We sought to determine whether adiposity in later midlife is an independent predictor of accelerated stiffening of the aorta. Whitehall II study participants (3789 men; 1383 women) underwent carotid-femoral applanation tonometry at the mean age of 66 and again 4 years later. General adiposity by body mass index, central adiposity by waist circumference and waist:hip ratio, and fat mass percent by body impedance were assessed 5 years before and at baseline. In linear mixed models adjusted for age, sex, ethnicity, and mean arterial pressure, all adiposity measures were associated with aortic stiffening measured as increase in pulse wave velocity (PWV) between baseline and follow-up. The associations were similar in the metabolically healthy and unhealthy, according to Adult Treatment Panel-III criteria excluding waist circumference. C-reactive protein and interleukin-6 levels accounted for part of the longitudinal association between adiposity and PWV change. Adjusting for chronic disease, antihypertensive medication and risk factors, standardized effects of general and central adiposity and fat mass percent on PWV increase (m/s) were similar (0.14, 95% confidence interval: 0.05-0.24, P=0.003; 0.17, 0.08-0.27, P<0.001; 0.14, 0.05-0.22, P=0.002, respectively). Previous adiposity was associated with aortic stiffening independent of change in adiposity, glycaemia, and lipid levels across PWV assessments. We estimated that the body mass index-linked PWV increase will account for 12% of the projected increase in cardiovascular risk because of high body mass index. General and central adiposity in later midlife were strong independent predictors of aortic stiffening. Our findings suggest that adiposity is an important and potentially modifiable determinant of arterial aging

    Porphyry indicator minerals and their mineral chemistry as vectoring and fertility tools

    Get PDF
    Information contained in this publication or product may be reproduced, in part or in whole, and by any means, for personal or public non-commercial purposes, without charge or further permission, unless otherwise specified. You can freely download the publication in its entirety by visiting the publisher's website
    • …
    corecore