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991.
Noh KT Shin SJ Son KH Jung ID Kang HK Lee SJ Lee EK Shin YK You JC Park YM 《Experimental & molecular medicine》2012,44(5):340-349
In this study, we showed the direct interaction between Mycobacterium avium subsp. paratuberculosis fibronectin attachment protein (FAP) and toll-like receptor4 (TLR4) via co-localization and binding by using confocal microscopy and co-immunoprecipitation assays. FAP triggered the expression of pro- and antiinflammatory cytokines in a TLR4-dependent manner. In addition, FAP-induced cytokine expression in bone marrow-derived dendritic cells (BMDCs) was modulated in part by glycogen synthase kinase-3 (GSK-3). FAP-induced expression of CD80, CD86, major histocompatibility complex (MHC) class I, and MHC class II in TLR4(+/+) BMDCs was not observed in TLR4(-/-) BMDCs. Furthermore, FAP induced DC-mediated CD8(+) T cell proliferation and cytotoxic T lymphocyte (CTL) activity, and suppressed tumor growth with DC-based tumor vaccination in EG7 thymoma murine model. Taken together, these results indicate that the TLR4 agonist, FAP, a potential immunoadjuvant for DC-based cancer vaccination, improves the DC-based immune response via the TLR4 signaling pathway. 相似文献
992.
Noh M Mok Y Lee S Kim H Lee SH Jin GW Seo JH Koo H Park TH Lee Y 《Chemical communications (Cambridge, England)》2012,48(32):3845-3847
Osmosis can be controlled reversibly and effectively by mild temperature changes based on novel thermosensitive solutes with LCST transition. The nBu-TAEA thermosensitive solution can draw fresh water from seawater at temperatures less than the phase separation temperature, and the osmotic flow was reversed at higher temperatures. 相似文献
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Liu G Choi KY Bhirde A Swierczewska M Yin J Lee SW Park JH Hong JI Xie J Niu G Kiesewetter DO Lee S Chen X 《Angewandte Chemie (International ed. in English)》2012,51(2):445-449
Delivering the goods: Multifunctional, self-assembled, polymeric nanoparticles for the simultaneous delivery of small-molecule drugs and siRNA have been synthesized. The nanoparticles are composed of biodegradable hyaluronic acid, for tumor targeting and cellular delivery, and a high siRNA binding affinity is provided by a Zn(II)-dipicolylamine analogue as an artificial phosphate-binding receptor (see scheme). 相似文献
996.
Y Zhou JW Shim C Fuentes-Hernandez A Sharma KA Knauer AJ Giordano SR Marder B Kippelen 《Physical chemistry chemical physics : PCCP》2012,14(34):12014-12021
We report on reversible changes of the work function (WF) values of indium-tin-oxide (ITO) under prolonged ultraviolet (UV) and air exposure. The WF of ITO is reduced from 4.7 eV to 4.2 eV by photon absorption in ITO under UV illumination or an air mass 1.5 solar simulator (100 mW cm(-2)). Air or oxygen exposure is found to increase the WF of ITO (UV-exposed) to a value of 4.6 eV. These changes of ITO's WF lead to reversible variations of the performance of organic photovoltaic devices where ITO acts primarily as the electron collecting or hole collecting electrode. These variations can be reflected in the disappearance (or appearance) of an S-shaped kink in the J-V characteristics upon continuous UV or solar simulator illumination (or air exposure). This reversible phenomenon is ascribed to the adsorption and desorption of oxygen on the surface and grain boundaries of ITO. The use of surface modifiers to either decrease or increase the WF of ITO in organic photovoltaic devices with inverted and conventional geometries is also shown to be an effective route to stabilize the device performance under UV illumination. 相似文献
997.
Han NS Shim HS Lee S Park SM Choi MY Song JK 《Physical chemistry chemical physics : PCCP》2012,14(30):10556-10563
The optical properties of single zinc oxide (ZnO) nanolasers are investigated. ZnO nanowires with different diameters and lengths are prepared by chemical vapor transport. The diameter plays an important role in the stimulated emission process in nanowires. The spectral shift and spacing of Fabry-Pérot-type modes imply a strong light-matter interaction in the lasing nanowires, which is explained by the exciton-polariton model. The polarization of the electric field in the lasing nanowires is perpendicular to the long axis of the nanowire and parallel to the substrate plane. The coexistence of the transverse modes is distinguished by decomposing the peak shape and the degree of polarization. In addition to the transverse mode of the lasing with the polarization parallel to the substrate plane, the lasing mode with the polarization perpendicular to the substrate plane is observed. 相似文献
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This paper proposes a new cytotoxicity assay in a microfluidic device with microwells and a distributive microfluidic channel network for the formation of cancer cell spheroids. The assay can generate rapid and uniform cell clusters in microwells and test in situ cytotoxicity of anticancer drugs including sequential drug treatments, long term culture of spheroids and cell viability assays. Inlet ports are connected to the microwells by a hydraulic resistance network. This uniform distribution of cell suspensions results in regular spheroid dimensions. Injected cancer cells were trapped in microwells, and aggregated into tumor spheroids within 3 days. A cytotoxicity test of the spheroids in microwells was subsequently processed in the same device without the extraction of cells. The in situ cytotoxicity assay of tumor spheroids in microwells was comparable with the MTT assay on hanging drop spheroids using a conventional 96-well plate. It was observed that the inhibition rate of the spheroids was less than that in the 2D culture dish and the effect on tumor spheroids was different depending on the anticancer drug. This device could provide a convenient in situ assay tool to assess the cytotoxicity of anticancer drugs on tumor spheroids, offering more information than the conventional 2D culture plate. 相似文献
1000.
We presented a novel platform for an ultrafast PCR system, called the Rotary PCR Genetic Analyzer, which incorporates a thermal block and resistive temperature detector (RTD) for thermal cycling control, a disposable PCR microchip, and a stepper motor. The influenza viral RNAs from H3N2, H5N1, and H1N1 were simultaneously identified with high sensitivity and speed. 相似文献