113 research outputs found

    Topical prostaglandin analogues and conjunctival inflammation in uveitic glaucoma.

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    A pilot study to determine whether topical prostaglandin analogues alter the expression of conjunctival inflammatory markers in patients with uveitic glaucoma.Prospective, single-masked case series of 20 patients with uveitis and secondary raised intraocular pressure. Participants were divided into four groups of five patients dependent on their use of topical medication: (1) prostaglandin analogues only, (2) corticosteroids only, (3) both prostaglandin analogues and corticosteroids, (4) no topical medication. Conjunctival cells were harvested by impression cytology and were examined for inflammatory markers (CD3, CD54, HLA-DR, CCR4, CCR5) by flow cytometry. A tear fluid sample was also examined for inflammatory cytokines (IL-12p70, IL-2, IL-10, IL-8, IL-6, IL-4, IL-5, IFN-gamma, IL-1beta, IFN-alpha, IFN-beta) by multiplex bead arrays.All groups demonstrated increased markers of conjunctival inflammation. There was no significant difference in levels of any inflammatory markers between the four groups, suggesting that the use of topical prostaglandin analogues does not increase conjunctival levels of inflammation beyond those already seen in uveitis.The use of topical prostaglandins does not appear to induce conjunctival inflammation over that which is already present in patients with uveitic glaucoma. This supports the use of topical prostaglandin analogues in patients with uveitic glaucoma, indicating that their use is unlikely to adversely affect subsequent glaucoma filtration surgery through the induction of chronic conjunctival inflammation

    INSTITUTIONS AND THE INTERNATIONAL DIFFUSION OF INFORMATION TECHNOLOG

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    The production and use of information technology (IT) in developed countries is wcll established and growing at a rapid pace. Newly industrializing countries are adopting both IT production and use as national goals. Developing countries are beginning to formulate plans to do the same. The institutional role in the international diffusion of IT is not well understood, but it is clear from the literature on innovation that the institutional role is critical. The paper makes four points. First, a traditional and fairly rigorous way of thinking about innovations - the economic perspective deriving from Schumpeter and Hicks - has been shown by studies from economic history and sociology/communications of innovation to be inadequate for explaining the dynamics of innovative change. The missing element is understanding of differential roles played by institutions. Second, among those promoting the need for institutional intervention there has been a debate about whether innovation is primarily supply-pushed or demand-pulled. The answer to the question has important institutional implications. The evidence, again mostly from economic history, shows it to be both, in iterative fashion. Thus institutions can intervene meaningfully on both sides. Third, there are two major forms of institutional intervention: influence and regulation. The possible intervention actions of institutions can be encompassed by a 2 x 2 matrix with supply-push and demand-pull on one dimension and influence and regulation on the other. Finally, if government wants to intervene, there are six classes of roles that might be pursued to affect innovation

    Elastomeric porous poly(glycerol sebacate) methacrylate (PGSm) microspheres as 3D scaffolds for chondrocyte culture and cartilage tissue engineering

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    Cartilage defects can be difficult to treat; therefore, tissue engineering of cartilage is emerging as a promising potential therapy. One interesting area of research explores the delivery of cells to the cartilage defect via scaffold-based cell delivery vehicles and microsurgery. This study explores the use of novel poly(glycerol sebacate) methacrylate (PGSm)-polymerised high internal phase emulsion (polyHIPE) microspheres as scaffolds with embedded cells for cartilage tissue engineering. Porous microsphere scaffolds (100 µm–1 mm diameter) were produced from emulsions consisting of water and a methacrylate-based photocurable resin of poly(glycerol sebacate). These resins were used in conjunction with a T-junction fluidic device and an ultraviolet (UV) curing lamp to produce porous microspheres with a tuneable size. This technique produced biodegradable PGSm microspheres with similar mechanical properties to cartilage. We further explore these microspheres as scaffolds for three-dimensional culture of chondrocytes. The microspheres proved to be very efficient scaffolds for primary chondrocyte culture and were covered by a dense extracellular matrix (ECM) network during the culture period, creating a tissue disk. The presence of glycosaminoglycans (GAGs) and collagen-II was confirmed, highlighting the utility of the PGSm microspheres as a delivery vehicle for chondrocytes. A number of imaging techniques were utilised to analyse the tissue disk and develop methodologies to characterise the resultant tissue. This study highlights the utility of porous PGSm microspheres for cartilage tissue engineering

    Evaluating Forecasting Methods

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    Ideally, forecasting methods should be evaluated in the situations for which they will be used. Underlying the evaluation procedure is the need to test methods against reasonable alternatives. Evaluation consists of four steps: testing assumptions, testing data and methods, replicating outputs, and assessing outputs. Most principles for testing forecasting methods are based on commonly accepted methodological procedures, such as to prespecify criteria or to obtain a large sample of forecast errors. However, forecasters often violate such principles, even in academic studies. Some principles might be surprising, such as do not use R-square, do not use Mean Square Error, and do not use the within-sample fit of the model to select the most accurate time-series model. A checklist of 32 principles is provided to help in systematically evaluating forecasting methods

    Complementarities between IT and Organizational Structure: The Role of Corporate Exploration and Exploitation

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    The decentralization of organizational decision authority has been shown to be complementary to Information Technology (IT) in prior research. We draw from the information processing view of organizations, the IT and de/centralization debate, and organizational learning theory to argue that IT payoffs can also be improved by greater centralization of decision authority, contingent on a firm’s corporate learning type. We argue that an exploratory learning type is best pursued with a decentralized organization design, while an exploitative learning type requires a centralized organization design. We hypothesize that under corporate exploration, IT payoffs are enhanced through greater decentralization, whereas under corporate exploitation, returns to IT are improved by greater centralization. Our study uses a novel multi‐source panel on the IT capital, the degree of de/centralization, and the performance of almost 260 German manufacturing firms. We estimate production functions to assess the contribution of combning IT with de/centralization to firmlevel productivity under different corporate learning types. Our results strongly support our hypotheses and hold up to a variety of robustness tests

    Topical prostaglandin analogues and conjunctival inflammation in uveitic glaucoma.

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    PURPOSE: A pilot study to determine whether topical prostaglandin analogues alter the expression of conjunctival inflammatory markers in patients with uveitic glaucoma. METHODS: Prospective, single-masked case series of 20 patients with uveitis and secondary raised intraocular pressure. Participants were divided into four groups of five patients dependent on their use of topical medication: (1) prostaglandin analogues only, (2) corticosteroids only, (3) both prostaglandin analogues and corticosteroids, (4) no topical medication. Conjunctival cells were harvested by impression cytology and were examined for inflammatory markers (CD3, CD54, HLA-DR, CCR4, CCR5) by flow cytometry. A tear fluid sample was also examined for inflammatory cytokines (IL-12p70, IL-2, IL-10, IL-8, IL-6, IL-4, IL-5, IFN-gamma, IL-1beta, IFN-alpha, IFN-beta) by multiplex bead arrays. RESULTS: All groups demonstrated increased markers of conjunctival inflammation. There was no significant difference in levels of any inflammatory markers between the four groups, suggesting that the use of topical prostaglandin analogues does not increase conjunctival levels of inflammation beyond those already seen in uveitis. CONCLUSIONS: The use of topical prostaglandins does not appear to induce conjunctival inflammation over that which is already present in patients with uveitic glaucoma. This supports the use of topical prostaglandin analogues in patients with uveitic glaucoma, indicating that their use is unlikely to adversely affect subsequent glaucoma filtration surgery through the induction of chronic conjunctival inflammation
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