1,448 research outputs found

    Angiogenesis in the synovium and at the osteochondral junction in osteoarthritis

    Get PDF
    SummaryObjectivesWe hypothesised that osteochondral and synovial angiogenesis in osteoarthritis (OA) are independent processes. We investigated whether indices of osteochondral and synovial angiogenesis display different relationships with synovitis, disease severity and chondrocalcinosis in patients with OA.DesignSynovium and medial tibial plateaux were obtained from 62 patients undergoing total knee joint replacement for OA (18 [29%] had chondrocalcinosis) and from 31 recently deceased people with no evidence of joint pathology post-mortem (PM). Vascular endothelium, proliferating endothelial cells (ECs) and macrophages were quantified by immunohistochemistry for CD34, CD31/Ki67 and CD14, respectively. Grades were assigned for radiographic and histological OA disease severity, clinical disease activity and histological synovitis (based on cellular content of the synovium).ResultsBlood vessels breached the tidemark in 60% of patients with OA and 20% of PM controls. Osteochondral vascular density increased with increasing cartilage severity and clinical disease activity scores, but not with synovitis. Synovial EC proliferation, inflammation and macrophage infiltration were higher in OA than in PM controls. Synovial angiogenesis indices increased with increasing histological synovitis, but were not related to osteochondral vascular density or other indices of OA disease severity. OA changes were more severe in patients with concurrent chondrocalcinosis. Chondrocalcinosis was not associated with increased angiogenesis or histological synovitis beyond that seen in OA alone.ConclusionOsteochondral and synovial angiogenesis appear to be independent processes. Osteochondral vascularity is associated with the severity of OA cartilage changes and clinical disease activity, whereas synovial angiogenesis is associated with histological synovitis. Modulation of osteochondral and synovial angiogenesis may differentially affect OA disease

    The physiological effects of elevated intra-abdominal pressure following aneurysm repair

    Get PDF
    AbstractObjectives: elevated intra-abdominal pressure (IAP) may cause widespread organ dysfunction (abdominal compartment syndrome) through effects on the respiratory, cardiac, renal and gastro-intestinal systems. The aim of this study was to document IAP following aneurysm surgery, and to determine the effect of IAH on outcome. Design: prospective observational study. Setting: University Hospital. Subjects: the patient cohort comprised 75 patients undergoing infra-renal aneurysm repair (53 non-ruptured [40 conventional - 1 death, 13 endovascular] and 22 conventionally repaired ruptured AAA - 8 deaths). IAP was quantified by bladder manometry at the termination of the procedure and at 24 h intervals in patients who remained intubated. Physiological indices of organ function were recorded. Statistical analysis utilized the unpaired t-test, Fischer's exact test and Pearson's correlation. Results: IAP was significantly higher at abdominal closure following ruptured aneurysm repair (15.4 mmHg [SE 1.6]) than conventional (10.5 [0.89]) or endovascular elective repair (6.4 [1.0]) of non-ruptured AAA. The sensitivity and specificity of IAP to predict subsequent mortality was analysed using a receiver characteristic operating curve. This analysis demonstrated that a cut off of 15 mmHg was the most useful for indicating patients at risk (sensitivity 0.66, specificity 0.79). Physiological indices of organ dysfunction (pH[p = 0.027], base excess [p = 0.005], peak inspiratory pressure [p = 0.0015], CVP and urine output [p = 0.0029]) were significantly impaired in patients with IAP ≥ 15 mmHg, in comparison to patients with lower pressures. IAP correlated significantly with indices of cardiac (CVP p = 0.038), respiratory (PaO2/FiO2, p = 0.026), and renal function (urine output p = 0.046). Conclusions: these data suggest that the management of IAH may have a role following repair of ruptured AAA. High intra-abdominal pressures rarely complicate elective or endovascular aneurysm repair.Eur J Vasc Endovasc Surg 26, 293-298 (2003

    Search for Solar Axions Using Fe-57

    Full text link
    We have made a search for Fe-57 gamma rays of energy 14.4 keV induced by resonant absorption of monochromatic solar axions, as proposed by Moriyama. The proposed axions are suggested to be emitted from the Sun, in M1 transitions between the first, thermally excited state and the ground state of Fe-57. An upper limit on hadronic axion mass of 745 eV is obtained at the 95% confidence level, it being assumed that z=0.56 and S=0.5.Comment: 4 pages, latex, revtex source, 1 postscript figure included, Title revised, some references added and expanded discussion. Version accepted by Phys. Lett.

    Tapping the large genetic variability for salinity tolerance in chickpea

    Get PDF
    Salinity is an ever-increasing problem in agriculture worldwide and especially in Australia. Improved genotypes that are well adapted to saline conditions are needed to enhance and sustain production in these areas. A screening of 263 accessions of chickpea, including 211 accessions from ICRISAT’s mini-core collection (10% of the core collection and 1% of the entire collection), showed a six-fold range of variation for seed yield under salinity, with several genotypes yielding 20% more than the previously-released salinity tolerant cultivar CSG8962. No significant relation was found between biomass at the late vegetative stage and final seed yield under salinity. Performance of seed yield under salinity was explained in part by the yield potential under control conditions, and a salinity tolerance component. The major trait related to salinity tolerance was the ability to maintain under salinity a large number of viable pods with seeds. In contrast, the relative seed size under salinity did not differ between tolerant and sensitive genotypes. Preliminary analysis of genotypic data for approximately 50 SSR markers on 211 genotypes revealed some associations with salinity tolerance that deserve a detailed analysis. Future effort should focus on the effect of salinity on the reproductive stage of development

    THE AMUNDSEN SEA LOW Variability, Change, and Impact on Antarctic Climate

    Get PDF
    The Amundsen Sea low (ASL) is a climatological low pressure center that exerts considerable influence on the climate of West Antarctica. Its potential to explain important recent changes in Antarctic climate, for example, in temperature and sea ice extent, means that it has become the focus of an increasing number of studies. Here, the authors summarize the current understanding of the ASL, using reanalysis datasets to analyze recent variability and trends, as well as ice-core chemistry and climate model projections, to examine past and future changes in the ASL, respectively. The ASL has deepened in recent decades, affecting the climate through its influence on the regional meridional wind field, which controls the advection of moisture and heat into the continent. Deepening of the ASL in spring is consistent with observed West Antarctic warming and greater sea ice extent in the Ross Sea. Climate model simulations for recent decades indicate that this deepening is mediated by tropical variability while climate model projections through the twenty-first century suggest that the ASL will deepen in some seasons in response to greenhouse gas concentration increases

    Some History of Functional Programming Languages

    Get PDF
    We study a series of milestones leading to the emergence of lazy, higher order, polymorphically typed, purely functional programming languages. An invited lecture given at TFP12, St Andrews University, 12 June 2012

    Absolute values of the London penetration depth in YBa2Cu3O6+y measured by zero field ESR spectroscopy on Gd doped single crystals

    Full text link
    Zero-field electron spin resonance (ESR) of dilute Gd ions substituted for Y in the cuprate superconductor YBa2_2Cu3_3O6+y_{\rm 6+y} is used as a novel technique for measuring the absolute value of the low temperature magnetic penetration depth λ(T0)\lambda(T\to 0). The Gd ESR spectrum of samples with 1\approx 1% substitution was obtained with a broadband microwave technique that measures power absorption bolometrically from 0.5 GHz to 21 GHz. This ESR spectrum is determined by the crystal field that lifts the level degeneracy of the spin 7/2 Gd3+^{3+} ion and details of this spectrum provide information concerning oxygen ordering in the samples. The magnetic penetration depth is obtained by relating the number of Gd ions exposed to the microwave magnetic field to the frequency-integrated intensity of the observed ESR transitions. This technique has allowed us to determine precise values of λ\lambda for screening currents flowing in the three crystallographic orientations (a^\hat a, b^\hat b and c^\hat c) in samples of Gdx_{\rm x}Y1x_{\rm 1-x}Ba2_2Cu3_3O6+y_{6+{\rm y}} of three different oxygen contents y=0.993{\rm y}=0.993 (Tc=89T_c = 89 K), y=0.77{\rm y}=0.77 (Tc=75T_c=75 K) and y=0.52{\rm y}=0.52 (Tc=56T_c=56 K). The in-plane values are found to depart substantially from the widely reported relation Tc1/λ2T_c\propto 1/\lambda^2.Comment: 14 pages, 12 figures; version to appear in PR

    Augmented reality meeting table: a novel multi-user interface for architectural design

    Get PDF
    Immersive virtual environments have received widespread attention as providing possible replacements for the media and systems that designers traditionally use, as well as, more generally, in providing support for collaborative work. Relatively little attention has been given to date however to the problem of how to merge immersive virtual environments into real world work settings, and so to add to the media at the disposal of the designer and the design team, rather than to replace it. In this paper we report on a research project in which optical see-through augmented reality displays have been developed together with prototype decision support software for architectural and urban design. We suggest that a critical characteristic of multi user augmented reality is its ability to generate visualisations from a first person perspective in which the scale of rendition of the design model follows many of the conventions that designers are used to. Different scales of model appear to allow designers to focus on different aspects of the design under consideration. Augmenting the scene with simulations of pedestrian movement appears to assist both in scale recognition, and in moving from a first person to a third person understanding of the design. This research project is funded by the European Commission IST program (IST-2000-28559)

    Fermionic partner of Quintessence field as candidate for dark matter

    Full text link
    Quintessence is a possible candidate for dark energy. In this paper we study the phenomenologies of the fermionic partner of Quintessence, the Quintessino. Our results show that, for suitable choices of the model parameters, the Quintessino is a good candidate for cold or warm dark matter. In our scenario, dark energy and dark matter of the Universe are connected in one chiral superfield.Comment: 4 pages, 3 figures, version to appear in PR
    corecore