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81.
Alanna M. Gilmour Samar Abdulkhalek Timothy S.W. Cheng Farah Alghamdi Preethi Jayanth Leah K. O’Shea Olivia Geen Luis A. Arvizu Myron R. Szewczuk 《Cellular signalling》2013,25(12):2587-2603
Epidermal growth factor (EGF)-induced EGFR tyrosine kinase receptor activation in cancer cell survival responses has become a strategic molecular-targeting clinical therapeutic intent, but the failures of these targeted approaches in the clinical setting demand alternate strategies. Here, we uncover a novel neuraminidase-1 (Neu1) and matrix metalloproteinase-9 (MMP-9) cross-talk in alliance with GPCR neuromedin B, which is essential for EGF-induced receptor activation and cellular signaling. Neu1 and MMP-9 form a complex with EGFR on the cell surface. Tamiflu (oseltamivir phosphate), anti-Neu1 antibodies, broad range MMP inhibitor galardin (GM6001), neuromedin B GPCR specific antagonist BIM-23127, the selective inhibitor of whole heterotrimeric G-protein complex BIM-46174 and MMP-9 specific inhibitor dose-dependently inhibited Neu1 activity associated with EGF stimulated 3T3–hEGFR cells. Tamiflu, anti-Neu1 antibodies and MMP9i attenuated EGFR phosphorylation associated with EGF-stimulated cells. Preclinical data provide the proof-of-evidence for a therapeutic targeting of Neu1 with Tamiflu in impeding human pancreatic cancer growth and metastatic spread in heterotopic xenografts of eGFP-MiaPaCa-2 tumors growing in RAGxCγ double mutant mice. Tamiflu-treated cohort exhibited a reduction of phosphorylation of EGFR-Tyr1173, Stat1-Tyr701, Akt-Thr308, PDGFRα-Tyr754 and NFκBp65-Ser311 but an increase in phospho-Smad2-Ser465/467 and -VEGFR2-Tyr1175 in the tumor lysates from the xenografts of human eGFP-MiaPaCa-2 tumor-bearing mice. The findings identify a novel promising alternate therapeutic treatment of human pancreatic cancer. 相似文献
82.
Raida Jallouli Ahmed Fendri Tahar Mechichi Youssef Talèl Gargouri Sofiane Bezzine 《Chirality》2013,25(1):35-38
Using the monomolecular film technique, we studied interfacial properties of Fusarium solani lipase (FSL). This lipolytic enzyme was found to be unique among the fungal lipases possessing not only a lipase activity but also a high phospholipase one.The FSL was able to hydrolyze dicaprin films at various surface pressures. The surface pressure dependency, the stereospecificity, and the regioselectivity of FSL were performed using optically pure stereoisomers of diglyceride (1,2‐sn‐ dicaprin and 2,3‐sn‐dicaprin) and a prochiral isomer (1,3‐sn‐dicaprin) spread as monomolecular films at the air–water interface. The FSL prefers adjacent ester groups of the diglyceride isomers (1,2‐sn‐dicaprin and 2,3‐sn‐dicaprin) at low and high surface pressures. Furthermore, FSL was found to be markedly stereospecific for the sn‐1 position of the 1,2‐sn‐enantiomer of dicaprin at both low and high surface pressures.Moreover, FSL shows high activities on phospholipids monolayers. However, this enzyme displays high preference to zwitterionic phospholipids compared to the negatively charged ones. Chirality, 25:35‐38, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
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Aseel J. Marzoq Nathalia Giese J?rg D. Hoheisel Mohamed Saiel Saeed Alhamdani 《The Journal of biological chemistry》2013,288(45):32517-32527
Pancreatic stellate cells are key mediators in chronic pancreatitis and play a central role in the development of pancreatic fibrosis, stromal formation, and progression of pancreatic cancer. This study was aimed at investigating molecular changes at the level of the proteome that are associated with the activation of pancreatic stellate cells by proinflammatory factors, namely TNF-α, FGF2, IL6, and chemokine (C-C motif) ligand 4 (CCL4). They were added individually to cells growing in serum-free medium next to controls in medium supplemented with serum, thus containing a mixture of them all, or in serum-free medium alone. Variations were detected by means of a microarray of 810 antibodies targeting relevant proteins. All tested factors triggered increased proliferation and migration. Further analysis showed that TNF-α is the prime factor responsible for the activation of pancreatic stellate cells. CCL4 is associated with cellular neovascularization, whereas FGF2 and IL6 induction led to better cellular survival and decreased apoptotic activity of the stellate cells. The identified direct effects of individual cytokines on human pancreatic stellate cells provide new insights about their contribution to pancreatic cancer promotion. 相似文献
85.
A hitherto unknown species of the dipteran family Ulidiidae is described from Iran and Turkey: Herina rajabii n. sp. is similar to H. gyrans (Loew) and H. tristis (Meigen), differing from them by the yellowish-brown scutellum and presence of a very strong subcercal prensiseta on the surstylus. A key to the species of the Herina tristis-group of species is provided. 相似文献
86.
Seyyed Saeed HOSSEINIAN YOUSEFKHANI Gentile Francesco FICETOLA Nasrullah RASTEGAR-POUYANI Natalia B ANANJEVA Eskandar RASTEGAR-POUYANI Rafaqat MASROOR 《亚洲两栖爬行动物研究(英文版)》2013,(3):207-213
Predictive potential distribution modeling is crucial in outlining habitat usage and establishing conservation management priorities. In this paper we provide detailed data on the distribution of the Caucasian rock agama Para- laudakia caucasia, and use species distribution models (MAXENT) to evaluate environmental suitability and potential distribution at a broad spatial scale. Locality data on the distribution of P. caucasia have been gathered over nearly its entire range by various authors from field surveys. The distribution model ofP caucasia showed good performance (AUC = 0.887), and predicted high suitability in regions mainly located in Tajikistan, north Pakistan, Afghanistan, southeast Turkmenistan, northeast Iran along the Elburz mountains, Transcaueasus (Azerbajan, Armenia, Georgia), northeastern Turkey and northward along the Caspian Sea coast in Daghestan, Russia. The identification of suitable areas for this species will help to assess conservation status of the species, and to set up management programs. 相似文献
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Mark A. Horsfield José L. Jara Nazia P. Saeed Ronney B. Panerai Thompson G. Robinson 《PloS one》2013,8(4)
A novel method is described for mapping dynamic cerebral blood flow autoregulation to assess autoregulatory efficiency throughout the brain, using magnetic resonance imaging (MRI). Global abnormalities in autoregulation occur in clinical conditions, including stroke and head injury, and are of prognostic significance. However, there is limited information about regional variations. A gradient-echo echo-planar pulse sequence was used to scan the brains of healthy subjects at a rate of 1 scan/second during a transient decrease in arterial blood pressure provoked by a sudden release of pressure in bilateral inflated thigh cuffs. The signal decrease and subsequent recovery were analyzed to provide an index of autoregulatory efficiency (MRARI). MRI time-series were successfully acquired and analyzed in eleven subjects. Autoregulatory efficiency was not uniform throughout the brain: white matter exhibited faster recovery than gray (MRARI = 0.702 vs. 0.672, p = 0.009) and the cerebral cortex exhibited faster recovery than the cerebellum (MRARI = 0.669 vs. 0.645, p = 0.016). However, there was no evidence for differences between different cortical regions. Differences in autoregulatory efficiency between white matter, gray matter and the cerebellum may be a result of differences in vessel density and vasodilation. The techniques described may have practical importance in detecting regional changes in autoregulation consequent to disease. 相似文献