排序方式: 共有57条查询结果,搜索用时 281 毫秒
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Scott M. Robinson Ginger Tsueng Jon Sin Vrushali Mangale Shahad Rahawi Laura L. McIntyre Wesley Williams Nelson Kha Casey Cruz Bryan M. Hancock David P. Nguyen M. Richard Sayen Brett J. Hilton Kelly S. Doran Anca M. Segall Roland Wolkowicz Christopher T. Cornell J. Lindsay Whitton Roberta A. Gottlieb Ralph Feuer 《PLoS pathogens》2014,10(4)
Coxsackievirus B3 (CVB3), a member of the picornavirus family and enterovirus genus, causes viral myocarditis, aseptic meningitis, and pancreatitis in humans. We genetically engineered a unique molecular marker, “fluorescent timer” protein, within our infectious CVB3 clone and isolated a high-titer recombinant viral stock (Timer-CVB3) following transfection in HeLa cells. “Fluorescent timer” protein undergoes slow conversion of fluorescence from green to red over time, and Timer-CVB3 can be utilized to track virus infection and dissemination in real time. Upon infection with Timer-CVB3, HeLa cells, neural progenitor and stem cells (NPSCs), and C2C12 myoblast cells slowly changed fluorescence from green to red over 72 hours as determined by fluorescence microscopy or flow cytometric analysis. The conversion of “fluorescent timer” protein in HeLa cells infected with Timer-CVB3 could be interrupted by fixation, suggesting that the fluorophore was stabilized by formaldehyde cross-linking reactions. Induction of a type I interferon response or ribavirin treatment reduced the progression of cell-to-cell virus spread in HeLa cells or NPSCs infected with Timer-CVB3. Time lapse photography of partially differentiated NPSCs infected with Timer-CVB3 revealed substantial intracellular membrane remodeling and the assembly of discrete virus replication organelles which changed fluorescence color in an asynchronous fashion within the cell. “Fluorescent timer” protein colocalized closely with viral 3A protein within virus replication organelles. Intriguingly, infection of partially differentiated NPSCs or C2C12 myoblast cells induced the release of abundant extracellular microvesicles (EMVs) containing matured “fluorescent timer” protein and infectious virus representing a novel route of virus dissemination. CVB3 virions were readily observed within purified EMVs by transmission electron microscopy, and infectious virus was identified within low-density isopycnic iodixanol gradient fractions consistent with membrane association. The preferential detection of the lipidated form of LC3 protein (LC3 II) in released EMVs harboring infectious virus suggests that the autophagy pathway plays a crucial role in microvesicle shedding and virus release, similar to a process previously described as autophagosome-mediated exit without lysis (AWOL) observed during poliovirus replication. Through the use of this novel recombinant virus which provides more dynamic information from static fluorescent images, we hope to gain a better understanding of CVB3 tropism, intracellular membrane reorganization, and virus-associated microvesicle dissemination within the host. 相似文献
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Edgley AJ Tare M Evans RG Skordilis C Parkington HC 《American journal of physiology. Regulatory, integrative and comparative physiology》2008,295(3):R829-R839
We assessed the relative contributions of endothelium-derived relaxing factors to renal vasodilation in vivo and determined whether these are altered in established streptozotocin-induced diabetes. In nondiabetic rats, stimulation of the endothelium by locally administered ACh or bradykinin-induced transient renal hyperemia. Neither basal renal blood flow (RBF) nor renal hyperemic responses to ACh or bradykinin were altered by blockade of prostanoid production (indomethacin) or by administration of charybdotoxin (ChTx) plus apamin to block endothelium-derived hyperpolarizing factor (EDHF). In contrast, combined blockade of nitric oxide (NO) synthase, N(omega)-nitro-l-arginine methyl ester (l-NAME), and prostanoid production reduced basal RBF and the duration of the hyperemic responses to ACh and bradykinin and revealed a delayed ischemic response to ACh. Accordingly, l-NAME and indomethacin markedly reduced integrated (area under the curve) hyperemic responses to ACh and bradykinin. Peak increases in RBF in response to ACh and bradykinin were not reduced by l-NAME and indomethacin but were reduced by subsequent blockade of EDHF. l-NAME plus indomethacin and ChTx plus apamin altered RBF responses to endothelium stimulation in a qualitatively similar fashion in diabetic and nondiabetic rats. The integrated renal hyperemic responses to ACh and bradykinin were blunted in diabetes, due to a diminished contribution of the component abolished by l-NAME plus indomethacin. We conclude that NO dominates integrated hyperemic responses to ACh and bradykinin in the rat kidney in vivo. After prior inhibition of NO synthase, EDHF mediates transient renal vasodilation in vivo. Renal endothelium-dependent vasodilation is diminished in diabetes due to impaired NO function. 相似文献
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Sanjeev R. Patil Ashish Asrondkar Vrushali Patil Jaiprakash N. Sangshetti Firoz A. Kalam Khan Manoj G. Damale Rajendra H. Patil Anil S. Bobade Devanand B. Shinde 《Bioorganic & medicinal chemistry letters》2017,27(16):3845-3850
A series of newer 1,2,4-triazole-3-thiol derivatives 5(a–m) and 6(a–i) containing a triazole fused with pyrazine moiety of pharmacological significance have been synthesized. All the synthesized compounds were screened for their in vitro antileishmanial and antioxidant activities. Compounds 5f (IC50 = 79.0 µM) and 6f (IC50 = 79.0 µM) were shown significant antileishmanial activity when compared with standard sodium stibogluconate (IC50 = 490.0 µM). Compounds 5b (IC50 = 13.96 µM) and 6b (IC50 = 13.96 µM) showed significant antioxidant activity. After performing molecular docking study and analyzing overall binding modes it was found that the synthesized compounds had potential to inhibit L. donovani pteridine reductase 1 enzyme. In silico ADME and metabolic site prediction studies were also held out to set an effective lead candidate for the future antileishmanial and antibacterial drug discovery initiatives. 相似文献
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Miranda C. Lewis Ben D. MacArthur Rahul S. Tare Richard O. C. Oreffo Colin P. Please 《PloS one》2016,11(2)
This article explores possible mechanisms governing extracellular matrix deposition in engineered cartilaginous cell pellets. A theoretical investigation is carried out alongside an experimental study measuring proteoglycan and collagen volume fractions within murine chondrogenic (ATDC-5) cell pellets. The simple mathematical model, which adopts a nutrient-dependent proteoglycan production rate, successfully reproduces the periphery-dominated proteoglycan deposition, characteristic of the growth pattern observed experimentally within pellets after 21 days of culture. The results suggest that this inhomogeneous proteoglycan production is due to nutrient deficiencies at the pellet centre. Our model analysis further indicates that a spatially uniform distribution of proteoglycan matrix could be maintained by initiating the culture process with a smaller-sized pellet. Finally, possible extensions are put forward with an aim to improve the model predictions for the early behaviour, where different mechanisms appear to dominate the matrix production within the pellets. 相似文献
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Nadine Tare 《Experimental cell research》2010,316(15):2527-2537
Activation of interleukin-1 family receptor ST2L by its ligand interleukin-33 (IL-33) is an important component in inflammatory responses. Peripheral blood basophils, recognized as major effector cells in allergic inflammation that play a role in both innate and adaptive immunity, are activated by IL-33 through ST2L. However, studies are challenging due to the paucity of this cell population, representing less than 1% of peripheral blood leukocytes. We identified a basophil-like chronic myelogenous leukemia cell line, KU812, that constitutively expresses ST2L and demonstrates functional responses to IL-33 stimulation. IL-33 induced production of multiple inflammatory mediators in KU812 cells that were blocked by anti-ST2L and anti-IL-33 antibodies. The interaction of IL-33 and ST2L activated NF-κB, JNK, and p38 MAPK, but not ERK1/2 signaling pathways. Studies using pharmacological inhibitors to IKK-2 and MAP kinases revealed that one of the functional responses, IL-33-induced IL-13 production, was regulated through NF-κB, but not JNK or p38 MAPK signaling. The requirement of NF-κB was confirmed by IKK-2 knockdown using shRNA. KU812 represents the first human cell line-based in vitro model of the IL-33/ST2L axis and provides a valuable tool to aid in understanding the mechanism and significance of IL-33 and ST2L interaction and function. 相似文献
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