539 research outputs found

    Regulation of COX-2 transcription in a colon cancer cell line by Pontin52/TIP49a

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    Cyclooxygenase-2 (COX-2) is expressed early in colon carcinogenesis and is known to play a crucial role in the progress of the disease. Here we show that the regulation of the expression of this enzyme in a colon cancer cell line, and in patients, is associated with overexpression of the Wnt pathway-associated proteins, Pontin52/TIP49a and LEF-1. Recently shown to be essential for transformation via the c-Myc pathway, Pontin52/TIP49a promotes COX-2 expression in tissue culture and is overexpressed in colon cancer tissue, co-localizing with COX-2 expression in transformed tissue, relative to paired normal tissue

    The utilisation of a standardised educational framework to develop and deliver impactful programmes of simulation-based learning

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    Simulation has become a well-integrated modality of learning in pre- and postgraduate healthcare education programmes. The use of advanced technologies and the delivery of complex simulation-based learning opportunities require adequate preparation of healthcare educators. This paper details a European collaborative development and utilisation of an educational framework designed to prepare educators for the delivery of simulation-based learning strategies. The framework was subsequently adapted by a commercial partner and an evaluative study identified the impact of this programme of education on United Kingdom Faculty and within the National Health Service utilising qualitative methods of enquiry.The evaluation study demonstrated that the use of the educational framework effectively educates faculty to construct and deliver simulation-based learning. Furthermore, the valuation demonstrated positive impacts on patient safety by increasing the confidence and skills of frontline staff and by improving the ‘preparedness’ of systems. It has also contributed to significant economic benefits within healthcare organisations

    The utilisation of a standardised educational framework to develop and deliver impactful programmes of simulation-based learning

    Get PDF
    Simulation has become a well-integrated modality of learning in pre- and postgraduate healthcare education programmes. The use of advanced technologies and the delivery of complex simulation-based learning opportunities require adequate preparation of healthcare educators. This paper details a European collaborative development and utilisation of an educational framework designed to prepare educators for the delivery of simulation-based learning strategies. The framework was subsequently adapted by a commercial partner and an evaluative study identified the impact of this programme of education on United Kingdom Faculty and within the National Health Service utilising qualitative methods of enquiry.The evaluation study demonstrated that the use of the educational framework effectively educates faculty to construct and deliver simulation-based learning. Furthermore, the valuation demonstrated positive impacts on patient safety by increasing the confidence and skills of frontline staff and by improving the ‘preparedness’ of systems. It has also contributed to significant economic benefits within healthcare organisations

    Integrin-dependent control of translation: engagement of integrin alphaIIbbeta3 regulates synthesis of proteins in activated human platelets.

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    Integrins are widely expressed plasma membrane adhesion molecules that tether cells to matrix proteins and to one another in cell-cell interactions. Integrins also transmit outside-in signals that regulate functional responses of cells, and are known to influence gene expression by regulating transcription. In previous studies we found that platelets, which are naturally occurring anucleate cytoplasts, translate preformed mRNA transcripts when they are activated by outside-in signals. Using strategies that interrupt engagement of integrin alphaIIbbeta3 by fibrinogen and platelets deficient in this integrin, we found that alphaIIbbeta3 regulates the synthesis of B cell lymphoma 3 (Bcl-3) when platelet aggregation is induced by thrombin. We also found that synthesis of Bcl-3, which occurs via a specialized translation control pathway regulated by mammalian target of rapamycin (mTOR), is induced when platelets adhere to immobilized fibrinogen in the absence of thrombin and when integrin alphaIIbbeta3 is engaged by a conformation-altering antibody against integrin alphaIIbbeta3. Thus, outside-in signals delivered by integrin alphaIIbbeta3 are required for translation of Bcl-3 in thrombin-stimulated aggregated platelets and are sufficient to induce translation of this marker protein in the absence of thrombin. Engagement of integrin alpha2beta1 by collagen also triggered synthesis of Bcl-3. Thus, control of translation may be a general mechanism by which surface adhesion molecules regulate gene expression

    Activated platelets mediate inflammatory signaling by regulated interleukin 1β synthesis

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    Platelets release preformed mediators and generate eicosanoids that regulate acute hemostasis and inflammation, but these anucleate cytoplasts are not thought to synthesize proteins or cytokines, or to influence inflammatory responses over time. Interrogation of an arrayed cDNA library demonstrated that quiescent platelets contain many messenger RNAs, one of which codes for interleukin 1β precursor (pro–IL-1β). Unexpectedly, the mRNA for IL-1β and many other transcripts are constitutively present in polysomes, providing a mechanism for rapid synthesis. Platelet activation induces rapid and sustained synthesis of pro–IL-1β protein, a response that is abolished by translational inhibitors. A portion of the IL-1β is shed in its mature form in membrane microvesicles, and induces adhesiveness of human endothelial cells for neutrophils. Signal-dependent synthesis of an active cytokine over several hours indicates that platelets may have previously unrecognized roles in inflammation and vascular injury. Inhibition of β3 integrin engagement markedly attenuated the synthesis of IL-1β, identifying a new link between the coagulation and inflammatory cascades, and suggesting that antithrombotic therapies may also have novel antiinflammatory effects

    Switching the Interpenetration of Confined Asymmetric Polymer Brushes

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    The interpenetration of two polymer brushes on approaching flat surfaces has been investigated. When compacting polymer brushes with an asymmetric charge on each surface, one neutral and the other weakly charged, we find that the brush interpenetration becomes a parameter that can be controlled by the pH of the hydrating solution. The switching between high and low degrees of brush interpenetration was investigated with numerical self-consistent field theory (nSCF) and experimentally using a sample environment which combines neutron reflectometry with a surface force type apparatus. Initially, a pair of uncharged poly(ethylene oxide), PEO, brushes are examined, where one of the brushes is deuterated to distinguish it from a hydrogenous counterpart. We find in both nSCF and these experiments that there is no significant overlap between the brushes as both compact into polymer blocks with little hydration. However, when a weak polyelectrolyte poly(2-(dimethylamino)ethyl methacrylate), PDMAEMA, brush is confined against a deuterated neutral PEO brush and the pH of the hydrating solution is below the polycation’s pKa of 7.5, then the presence of charged groups on the PDMAEMA allows significant interpenetration to occur between the two polymer brushes on contact. This interpenetration remains once the polymer brushes dehydrate due to the confining pressure that is applied. Raising the pH to a value above the pKa, removes the charges from the polyelectrolyte brush resulting in little to no interpenetration between the two brushes. Therefore, by simply adjusting the pH of the hydrating solution the interpenetration state between polymer brush pairs can be switched when one brush is a weak polyelectrolyte. Since polymer brushes are widely investigated and used to reduce friction between solid surfaces, this effect may have significant implications in the design and operation of polymer brushes with controllable friction properties
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