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Fruiting bodies of Cordyceps cicadae (CC) have been reported to have a therapeutic effect in chronic kidney disease. Due to the rare and expensive resources from natural habitats, artificially cultivated mycelia using submerged liquid cultivation of CC (CCM) have been recently developed as an alternative to scarce sources of CC. However, little is known regarding potential protective effects of CCM against cyclosporine A (CsA)-induced acute nephrotoxicity in vivo and in vitro. In this study, male Sprague-Dawley rats were divided into six groups: control, CCM (40 mg and 400 mg/kg, orally), CsA (10 mg/kg, oral gavage), and CsA + CCM (40 mg and 400 mg/kg, orally). At the end of the study on day 8, all rats were sacrificed, and the blood and kidneys retrieved. CsA-induced acute nephrotoxicity was evident by increased levels of blood urea nitrogen (BUN). Levels of the endoplasmic reticulum (ER) resident chaperone glucose regulated protein 78 (GRP 78) were increased significantly in rats with acute nephrotoxicity. BUN and GRP 78 were significantly ameliorated in synchronous oral groups of CCM (40 or 400 mg/kg) plus CsA. Examination of hematoxylin and eosin stained kidney tissues revealed that the combined treatment of CCM slightly improved vacuolization in renal tubules upon CsA-induced damage. CsA-induced down-regulation of protein expression of magnesium ion channel proteins and transient receptor potential melastatin 6 and 7 were abolished by the combined treatment of CCM. CCM has the potential to protect the kidney against CsA-induced nephrotoxicity by reducing magnesium ion wasting, tubular cell damage, and ER stress demonstrated further by human renal proximal tubular epithelial cell line HK-2. Our results contribute to the in-depth understanding of the role of polysaccharides and nucleobases as the main secondary metabolites of CCM in the defense system of renal functions in CsA-induced acute nephrotoxicity. [ABSTRACT FROM AUTHOR]

In this paper, we apply the game theory to study some strategic actions for retailers to fight a price war. We start by modeling a noncooperative pure pricing game among multiple competing retailers who sell a certain branded product under price-dependent stochastic demands. A unique Nash equilibrium is proven to exist under some mild conditions. We demonstrate mathematically the incentives for retailers to start a price war. Based on a strategic framework via the game theory, we illustrate the use of service level to build price walls which can prevent a huge drop in price, as well as profit. Three kinds of price walls are proposed, and the respective strengths and weaknesses have been studied. Analytical conditions, under which a price wall can effectively prevent big drops in both market share and profit, are developed. Aside from the proposed price wails, two other pricing strategies, which can lead to an all-win situation, are examined. Index Terms--Game theory, price war, pricing game, retailing, service level.