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Poulet B.,Royal Veterinary College University of London
Arthritis and rheumatism | Year: 2012

Chronological age is a powerful epidemiologic risk factor for osteoarthritis (OA), a multifactorial disease that is characterized by articular cartilage (AC) degradation. It is unclear from a molecular perspective how aging interacts with OA to produce this risk to AC integrity. To address this key question, we used in vivo time-course analysis of OA development and murine interstrain variability in natural susceptibility to OA to examine changes in non-OA-prone CBA mice versus OA-prone STR/Ort mice, which develop disease that bears significant histologic resemblance to human OA. Through global transcriptome profiling, we attempted to discover the molecular signature linked with both OA vulnerability and progression. Affymetrix Mouse Gene 1.0 ST Array profiles were generated from AC samples derived from CBA and STR/Ort mice at 3 different ages, corresponding to the stages prior to, at, and late after the natural onset of OA in the STR/Ort mice. We found that the OA in STR/Ort mice exhibited a molecular phenotype resembling human OA, and we pinpointed a central role of NF-κB signaling and the emergence of an immune-related signature in OA cartilage over time. We discovered that, strikingly, young healthy AC has a highly expressed skeletal muscle gene expression program, which is switched off during maturation, but is intriguingly retained in AC during OA development in STR/Ort mice. This study is the first to show that AC chondrocytes share a high-abundance gene-expression program with skeletal muscle. We show that failure to switch this program off, as well as the restoration of this program, is associated with inappropriate expression of NF-κB signaling pathways, skeletal muscle-related genes, and induction and/or progression of OA. Copyright © 2012 by the American College of Rheumatology. Source

Allenspach K.,Royal Veterinary College University of London
Veterinary Clinics of North America - Small Animal Practice | Year: 2011

The mucosal immune system is at the forefront of defense against invading pathogens, but at the same time, it must maintain tolerance toward commensals and food antigens in the intestinal lumen. The interplay between the innate immune response and commensal microorganisms is essential to maintaining this balance. Great progress has been made in identifying some of the genetic predispositions underlying inflammatory bowel disease in certain breeds, such as the German shepherd dog. Several immunologic markers are discussed with respect to their clinical usefulness in the diagnosis and management of inflammatory bowel disease. © 2011 Elsevier Inc. Source

Haddadi H.,Royal Veterinary College University of London
Computer Communication Review | Year: 2010

Online advertising is currently the richest source of revenue for many Internet giants. The increased number of online businesses, specialized websites and modern profiling techniques have all contributed to an explosion of the income of ad brokers from online advertising. The single biggest threat to this growth, is however, click-fraud. Trained botnets and individuals are hired by click-fraud specialists in order to maximize the revenue of certain users from the ads they publish on their websites, or to launch an attack between competing businesses. In this note we wish to raise the awareness of the networking research community on potential research areas within the online advertising field. As an example strategy, we present Bluff ads; a class of ads that join forces in order to increase the effort level for click-fraud spammers. Bluff ads are either targeted ads, with irrelevant display text, or highly relevant display text, with irrelevant targeting information. They act as a litmus test for the legitimacy of the individual clicking on the ads. Together with standard threshold-based methods, fake ads help to decrease click-fraud levels. Source

Usherwood J.R.,Royal Veterinary College University of London
Biology Letters | Year: 2013

Larger terrestrial animals tend to support their weight with more upright limbs. This makes structural sense, reducing the loading on muscles and bones, which is disproportionately challenging in larger animals. However, it does not account for why smaller animals are more crouched; instead, they could enjoy relatively more slender supporting structures or higher safety factors. Here, an alternative account for the scaling of posture is proposed, with close parallels to the scaling of jump performance. If the costs of locomotion are related to the volume of active muscle, and the active muscle volume required depends on both the work and the power demanded during the push-off phase of each step (not just the net positive work), then the disproportional scaling of requirements for work and push-off power are revealing. Larger animals require relatively greater active muscle volumes for dynamically similar gaits (e.g. top walking speed)-which may present an ultimate constraint to the size of running animals. Further, just as for jumping, animals with shorter legs and briefer push-off periods are challenged to provide the power (not the work) required for push-off. This can be ameliorated by having relatively long push-off periods, potentially accounting for the crouched stance of small animals. Source

Braid F.,Royal Veterinary College University of London
Anatomical sciences education | Year: 2012

Recognition of anatomical landmarks in live animals (and humans) is key for clinical practice, but students often find it difficult to translate knowledge from dissection-based anatomy onto the live animal and struggle to acquire this vital skill. The purpose of this study was to create and evaluate the use of an equine anatomy rug ("Anato-Rug") depicting topographical anatomy and key areas of lung, heart, and gastrointestinal auscultation, which could be used together with a live horse to aid learning of "live animal" anatomy. Over the course of 2 weeks, 38 third year veterinary students were randomly allocated into an experimental group, revising topographical anatomy from the "Anato-Rug," or a control group, learning topographical anatomy from a textbook. Immediately post activity, both groups underwent a test on live anatomy knowledge and were retested 1 week later. Both groups then completed a questionnaire to ascertain their perceptions of their learning experiences. Results showed that the experimental groups scored significantly higher than the control group at the first testing session, experienced more enjoyment during the activity and gained more confidence in identifying anatomical landmarks than the control group. There was not a significant difference in scores between groups at the second testing session. The findings indicate that the anatomy rug is an effective learning tool that aids understanding, confidence, and enjoyment in learning equine thorax and abdominal anatomy; however it was not better than traditional methods with regards to longer term memory recall. Copyright © 2012 American Association of Anatomists. Source

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