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Nonsteroidal anti-inflammatory drugs alter vasa recta diameter via pericytes
We have previously shown that vasa recta pericytes are known to dilate vasa recta capillaries in the presence of PGE2 and contract vasa recta capillaries when endogenous production of PGE2 is inhibited by the nonselective nonsteroidal anti-inflammatory drug (NSAID) indomethacin. In the present study, we used a live rat kidney slice model to build on these initial observations and provide novel data that demonstrate that nonselective, cyclooxygenase-1-selective, and cyclooxygenase -2-selective NSAIDs act via medullary pericytes to elicit a reduction of vasa recta diameter. Real-time images of in situ vasa recta were recorded, and vasa recta diameters at pericyte and nonpericyte sites were measured offline. PGE2 and epoprostenol (a prostacyclin analog) evoked dilation of vasa recta specifically at pericyte sites, and PGE2 significantly attenuated pericyte-mediated constriction of vasa recta evoked by both endothelin-1 and ANG II. NSAIDs (indomethacin > SC-560 > celecoxib > meloxicam) evoked significantly greater constriction of vasa recta capillaries at pericyte sites than at nonpericyte sites, and indomethacin significantly attenuated the pericyte-mediated vasodilation of vasa recta evoked by PGE2, epoprostenol, bradykinin, and S-nitroso-N-acetyl-l-penicillamine. Moreover, a reduction in PGE2 was measured using an enzyme immune assay after superfusion of kidney slices with indomethacin. In addition, immunohistochemical techniques were used to demonstrate the population of EP receptors in the medulla. Collectively, these data demonstrate that pericytes are sensitive to changes in PGE2 concentration and may serve as the primary mechanism underlying NSAID-associated renal injury and/or further compound-associated tubular damage
From Innovation to Diversification: A Simple Competitive Model
Few attempts have been proposed in order to describe the statistical features and historical evolution of the export bipartite matrix countries/products. An important standpoint is the introduction of a products network, namely a hierarchical forest of products that models the formation and the evolution of commodities. In the present article, we propose a simple dynamical model where countries compete with each other to acquire the ability to produce and export new products. Countries will have two possibilities to expand their export: innovating, i.e. introducing new goods, namely new nodes in the product networks, or copying the productive process of others, i.e. occupying a node already present in the same network. In this way, the topology of the products network and the country-product matrix evolve simultaneously, driven by the countries push toward innovation
’Body Politics: Charles Brandoin’s France England, 1772’
The article analyses a satirical print that was published in London by a Swiss artist, Charles Brandoin (1733–1796). Unusually, the design articulates ideas of national difference via an iconography of food and drink. A close reading of contemporary visual and textual sources relating to food, diet and national character are used to unravel the print’s satirical meanings and to highlight an aspect of the design that has been lost in contemporary discussions: that this double national satire contrasts the French cook as poisoner, with the English cook as savage
Free of Language: "Soundscapes"
A review of "Soundscapes", an exhibition at The National Gallery featuring the responses of six contemporary composers and sound artists to the question of how might music and visual art unite to produce something greater than their constituent parts. Chris Watson and Akseli Gallen-Kallela are among the featured artists