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171.
Shannon Bunker Joanna Holeniewska Sauparnika Vijay Annegret Dahlmann-Noor Peng Khaw Yin-Shan Ng David Shima Richard Foxton 《Journal of visualized experiments : JoVE》2015,(96)
Progress in understanding the pathophysiology, and providing novel treatments for glaucoma is dependent on good animal models of the disease. We present here a protocol for elevating intraocular pressure (IOP) in the rat, by injecting magnetic microspheres into the anterior chamber of the eye. The use of magnetic particles allows the user to manipulate the beads into the iridocorneal angle, thus providing a very effective blockade of fluid outflow from the trabecular meshwork. This leads to long-lasting IOP rises, and eventually neuronal death in the ganglion cell layer (GCL) as well as optic nerve pathology, as seen in patients with the disease. This method is simple to perform, as it does not require machinery, specialist surgical skills, or many hours of practice to perfect. Furthermore, the pressure elevations are very robust, and reinjection of the magnetic microspheres is not usually required unlike in some other models using plastic beads. Additionally, we believe this method is suitable for adaptation for the mouse eye. 相似文献
172.
Prostaglandin E2 (PGE2) is a bioactive lipid that can elicit a wide range of biological effects associated with inflammation and cancer. The physiological roles of PGE2 are diverse, mediated in part through activation of key downstream signaling cascades via transmembrane EP receptors located on the cell surface. Elevated levels of COX-2 and concomitant overproduction of PGE2 are often found in human cancers. These observations have led to the use of non-steroidal anti-inflammatory drugs (NSAIDs) as chemopreventive agents, particularly for colorectal cancer (CRC). Their long-term use, however, may be associated with gastrointestinal toxicity and increased risk of adverse cardiovascular events, prompting the development of other enzymatic targets in this pathway. This review will focus on recent efforts to target the terminal synthase, mPGES-1, for cancer chemoprevention. The role of mPGES-1 in the pathogenesis of various cancers is discussed. In addition, an overview of recent efforts to develop small molecule inhibitors that target the protein with high selectivity is also be reviewed. 相似文献
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Gundi VA Kosoy MY Myint KS Shrestha SK Shrestha MP Pavlin JA Gibbons RV 《Applied and environmental microbiology》2010,76(24):8247-8254
Bartonellae were detected in a total of 152 (23.7%) of 642 tissues from 108 (48.4%) of 223 small mammals trapped in several urban areas of Nepal. Based on rpoB and gltA sequence analyses, genotypes belonging to seven known Bartonella species and five genotypes not belonging to previously known species were identified in these animals. 相似文献
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The luminescent properties and energy transfer (ET) mechanism in the Ln3+ pair of the RE3+ (RE = Eu3+, Ce3+, Dy3+ and Sm3+) doped K4Ca(PO4)2 phosphor were successfully investigated using a conventional high-temperature solid-state reaction. In the near infrared (NIR) range, Ce3+-doped K4Ca(PO4)2 phosphor exhibited a UV–Vis. emission band, whereas K4Ca(PO4)2:Dy3+ exhibited characteristic emission bands centred at 481 and 576 nm in the near-ultraviolet excitation range. The possibility of ET from Ce3+ to Dy3+ in K4Ca(PO4)2 phosphor was confirmed by a significant increase in the photoluminescence intensity of the Dy3+ ion based on the spectral overlap of acceptor and donor ions. X-ray diffraction, Fourier-transform infrared and thermogravimetric analysis/differential thermal analysis TGA/DTA were carried out to study phase purity, presence of functional groups and amount of weight loss under different temperature regimes. Therefore, the RE3+-doped K4Ca(PO4)2 phosphor may be a stable phosphor host for light-emitting diode applications. 相似文献
179.
Kim KJ Matsukawa Y Yamahara H Kalra VK Lee VH Crandall ED 《American journal of physiology. Lung cellular and molecular physiology》2003,284(3):L458-L465
Transport characteristics of intact albumin were investigated using primary cultured rat alveolar epithelial cell monolayers. The apical-to-basolateral (ab) flux of intact fluorescein isothiocyanate (FITC)-labeled albumin (F-Alb) is greater than basolateral-to-apical (ba) flux at the same upstream [F-Alb]. Net absorption of intact F-Alb occurs with half-maximal concentration of approximately 1.6 microM and maximal transport rate of approximately 0.15 fmol.cm(-2).s(-1). At 15 and 4 degrees C, both ab and ba F-Alb fluxes are not different from zero, collapsing net absorption. The presence of excess unlabeled albumin (but not other macromolecule species) in either the apical or basolateral fluid significantly reduces both ab and ba unidirectional F-Alb fluxes. Photoaffinity labeling of apical cell membranes revealed an approximately 60-kDa protein that exhibits specificity for albumin. These data indicate that net absorption of intact albumin takes place via saturable receptor-mediated transcellular endocytotic processes recognizing albumin, but not other macromolecules, that may play an important role in alveolar homeostasis in the mammalian lung. 相似文献
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