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71.
5-Lipoxygenase converts arachidonic acid into leukotrienes, which are involved in inflammation and angiogenesis. The introduction of carboranes can improve the pharmacokinetic behavior of metabolically less stable pharmaceutics. Herein we report the syntheses of several carborane-based inhibitors of the 5-lipoxygenase pathway. The isosteric replacement of phenyl rings by carboranes leads to improved cytotoxicity toward several melanoma and colon cancer cell lines. For the colon cancer cell line HCT116, the co-inhibition of heat shock protein 90 was observed.  相似文献   
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The aim of the present research was to study the chemical profile of volatile and non-volatile compounds in freeze- and spray-dried oregano, thyme, sage, and rosemary as well as to study the gastrointestinal stability and the biological activity of the samples after encapsulation using two proteins (soy and whey). Chemical analysis was performed by HS-SPME/GC-MS and HPLC-PDA techniques. The antioxidant activity (FRAP, DPPH and ORAC assays) and HPLC-PDA analyses were performed before and after simulated two-phase digestion process (gastric and duodenal) using human gastrointestinal enzymes. The effect of protein carriers was depended on the plant matrix and the class of compound. Soy protein is useful for the protection of thymol and carvacrol content in thyme and the increase of the antioxidant activity of sage. Whey protein is useful for flavanols stability in all studied herbs before and after the duodenal digestive phase.  相似文献   
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Polymer composite films of tris-(8-hydroxy-quinoline) aluminum (Alq3) and polymethyl methacrylate (PMMA) at two different concentrations were investigated. Dielectric properties of the samples were measured in broad frequency range and results show an increase in specific conductance and susceptance by adding Alq3 in PMMA. Changes in dielectric spectra caused by irradiation of the samples with LED lamps at different wavelengths were also recorded. The samples were examined by UV–Vis and Fourier transform infrared spectroscopy. The interaction between Alq3 and the polymer matrix was observed in the photoluminescence spectroscopy spectra. The doping of the PMMA with different concentrations of the Alq3 leads to the unique photodielectric properties of the resulting composite, and that is the main result of this study. Due to its interesting optical and photodielectric properties, PMMA/Alq3 film may find application in solar cells and optoelectronics.  相似文献   
74.
Magnetic nanoparticles have garnered sustained research interest for their promise in biomedical applications including diagnostic imaging, triggered drug release, cancer hyperthermia, and neural stimulation. Many of these applications make use of heat dissipation by ferrite nanoparticles under alternating magnetic fields, with these fields acting as an externally administered stimulus that is either present or absent, toggling heat dissipation on and off. Here, an extension of this concept, magnetothermal multiplexing is demonstrated, in which exposure to alternating magnetic fields of differing amplitude and frequency can result in selective and independent heating of magnetic nanoparticle ensembles. The differing magnetic coercivity of these particles, empirically characterized by a custom high amplitude alternating current magnetometer, informs the systematic selection of a multiplexed material system. This work culminates in a demonstration of magnetothermal multiplexing for selective remote control of cellular signaling in vitro.  相似文献   
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Nonsteroidal anti-inflammatory drugs (NSAIDs) are the most common way of treating inflammatory disorders. Their widespread use helped reveal their other modes of action as pharmaceuticals, such as a profound effect on various cancers. Celecoxib has proven to be a very prominent member of this group with cytostatic activities. On the other hand, the highly dynamic field of drug design is constantly searching for new ways of modifying known structures to obtain more powerful and less harmful drugs. A very interesting development is the implementation of carboranes in pharmacologically active structures, mostly as phenyl mimetics. Herein we report the synthesis of three carborane-containing derivatives of the COX-2-selective NSAID celecoxib. The new compounds proved to have promising cytostatic potential against various melanoma and colorectal adenocarcinoma cell lines. Inhibited proliferation accompanied by caspase-independent apoptotic cell death was found to be the main cause of decreased cell viability upon treatment with the most efficient celecoxib analogue, 3 b (4-[5-(1,7-dicarba-closo-dodecaboranyl)-3-trifluoromethyl-1H-pyrazol-1-yl]-1-methylsulfonylbenzene).  相似文献   
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Bronchiolitis obliterans organizing pneumonia (BOOP) is a well-defined clinicopathological entity. The aetiology of BOOP is generally unknown, although it has been associated with specific diseases or various pharmaceutical drugs. The amiodarone is one of them. We report a patient with BOOP secondary to amiodarone therapy, who presented with cough, fever and sputum production, dyspnoea and night sweats lasting for two months. A chest radiograph showed bilateral patchy and interstitial infiltrates. Lymphocyte phenotyping of bronchoalveolar lavage fluid showed decreased ratio of CD4+:CD8+ lymphocytes. Transbronchial lung biopsy established the diagnosis of BOOP. After stopping amiodarone therapy, symptoms disappeared and the chest radiograph remained normal within two months.  相似文献   
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The article reports on a simulation appraisal of energy consumption, energy costs and environment impact of three systems used for space heating, and space cooling of an office building in Kragujevac, Serbia. Three investigated systems are (1) a system with a natural gas boiler and convective baseboard heaters for water space heating and window air conditioners for air space cooling; (2) a system with a natural gas boiler and individual air reheaters for air space heating and a chiller plant for air space cooling; and (3) an air-to-air heat pump for air space heating, and cooling. The systems are modeled and simulated by using EnergyPlus software. After simulations, it is found that the first investigated system has the highest energy efficiency, the best economy, and the lowest environmental impact. That is because of the fact that the first system has water as a heating medium and uses predominantly natural gas as fuel. However, in future, when for generation the grid electrical energy requires less primary energy, and becomes decarbonized, the third system would be best to conserve energy resources and environment.  相似文献   
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