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排序方式: 共有540条查询结果,搜索用时 296 毫秒
531.
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Lavinia Raimondi Angela De Luca Nicola Amodio Mauro Manno Samuele Raccosta Simona Taverna Daniele Bellavia Flores Naselli Simona Fontana Odessa Schillaci Roberto Giardino Milena Fini Pierfrancesco Tassone Alessandra Santoro Giacomo De Leo Gianluca Giavaresi Riccardo Alessandro 《Oncotarget》2015,6(15):13772-13789
Bone disease is the most frequent complication in multiple myeloma (MM) resulting in osteolytic lesions, bone pain, hypercalcemia and renal failure. In MM bone disease the perfect balance between bone-resorbing osteoclasts (OCs) and bone-forming osteoblasts (OBs) activity is lost in favour of OCs, thus resulting in skeletal disorders. Since exosomes have been described for their functional role in cancer progression, we here investigate whether MM cell-derived exosomes may be involved in OCs differentiation. We show that MM cells produce exosomes which are actively internalized by Raw264.7 cell line, a cellular model of osteoclast formation. MM cell-derived exosomes positively modulate pre-osteoclast migration, through the increasing of CXCR4 expression and trigger a survival pathway. MM cell-derived exosomes play a significant pro-differentiative role in murine Raw264.7 cells and human primary osteoclasts, inducing the expression of osteoclast markers such as Cathepsin K (CTSK), Matrix Metalloproteinases 9 (MMP9) and Tartrate-resistant Acid Phosphatase (TRAP). Pre-osteoclast treated with MM cell-derived exosomes differentiate in multinuclear OCs able to excavate authentic resorption lacunae. Similar results were obtained with exosomes derived from MM patient''s sera. Our data indicate that MM-exosomes modulate OCs function and differentiation. Further studies are needed to identify the OCs activating factors transported by MM cell-derived exosomes. 相似文献
533.
Wang LM; Michieli P; Lie WR; Liu F; Lee CC; Minty A; Sun XJ; Levine A; White MF; Pierce JH 《Blood》1995,86(11):4218-4227
Interleukin-13 (IL-13) induced a potent mitogenic response in IL-3- dependent TF-1 cells and DNA synthesis to a lesser extent in MO7E and FDC-P1 cells. IL-13 stimulation of these lines, like IL-4 and insulin- like growth factor-1 (IGF-1), resulted in tyrosine phosphorylation of a 170-kD substrate. The tyrosine-phosphorylated 170-kD substrate strongly associated with the 85-kD subunit of phosphoinositol-3 (PI-3) kinase and with Grb-2. Anti-4PS serum readily detected the 170-kD substrate in lysates from both TF-1 and FDC-P1 cells stimulated with IL-13 or IL-4. These data provide evidence that IL-13 induces tyrosine phosphorylation of the 4PS substrate, providing an essential interface between the IL- 13 receptor and signaling molecules containing SH2 domains. IL-13 and IL-4 stimulation of murine L cell fibroblasts, which endogenously express the IL-4 receptor (IL-4R alpha) and lack expression of the IL-2 receptor gamma subunit (IL-2R gamma), resulted in tyrosine phosphorylation of insulin receptor substrate-1 (IRS-1)/4PS. Enhanced tyrosine phosphorylation of IRS-1/4PS was observed in response to IL-4, but not IL-13 treatment of L cells transfected with the IL-2R gamma chain. These results indicate that IL-13 does not use the IL-2R gamma subunit in its receptor complex and that expression of IL-2R gamma enhances, but is not absolutely required for mediating IL-4-induced tyrosine phosphorylation of IRS-1/4PS. 相似文献
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AIM:To isolate,characterize and investigate the antifungal activity of the root bark of Psorospermum corymbiferum(Clusiaceae).METHODS:The finely ground root bark of Psorospermum corymbiferum was cold-extracted by percolation with 98% ethanol(5.0 L) for two weeks.The ethanol extract was macerated with n-hexane,chloroform,ethylacetate and methanol successively to give the respective solvent extracts.Fractionation of the extract was done using column chromatography on silica gel with cyclohexene:ethylacetate(1... 相似文献
537.
G Merino R Real MF Baro L Gonzalez-Lobato JG Prieto AI Alvarez MM Marques 《Drug metabolism and disposition》2009,37(1):5-9
ATP-binding cassette transporter ABCG2 [breast cancer resistance protein (BCRP)] is a member of the ABC transporter superfamily that actively extrudes xenotoxins from cells and is a major determinant of the bioavailability of many compounds. ABCG2 expression is strongly induced during lactation in the mammary gland and is related to the active secretion of drugs into the milk. The presence of drug residues and environmental pollutants in milk is an outstanding problem for human milk consumption and milk industrial processes, involving important risks to public health and the dairy industry. In cows, a single nucleotide polymorphism (SNP) in this protein has been described previously (Tyr581) and is associated with higher fat and protein percentages and lower milk yield. However, whether this amino acid substitution affects ABCG2-mediated drug transport in cows, including milk secretion, required further exploration. We cloned the two variants of bovine ABCG2 and evaluated the effect of this SNP on mitoxantrone accumulation assays performed in ovine primary fibroblasts transiently expressing either of the variants. It is interesting to note that statistically significant differences in activity between both variants were observed, and the Ser581 variant was related with an increased efflux activity. In addition, we demonstrated that genistein is a very good inhibitor of bovine ABCG2 and identified new inhibitors of the transporter, such as the macrocyclic lactones, ivermectin, and selamectin. Moreover, the inhibitory effect of these compounds on human and murine ABCG2 homologs was confirmed using transduced Marbin-Dabin canine kidney II cells. These findings may have important implications regarding the presence of drug residues in milk and drug interactions affecting the pharmacological behavior of ABCG2 substrates. 相似文献
538.
Elegance TP Lam Cindy LK Lam CL Lai MF Yuen Daniel YT Fong Thomas MK So 《Health and quality of life outcomes》2009,7(1):52
Background
Few studies have evaluated the health-related quality of life (HRQOL) of Southern Chinese with chronic hepatitis B (CHB) infection. 相似文献539.