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Ultraviolet (UV) radiation activates cell signaling pathways in melanocytes. As a result of altered signaling pathways and UV-induced cellular damage, melanocytes can undergo oncogenesis and develop into melanomas. In this study, we investigated the effect of UV-radiation on p38 MAPK (mitogen-activated protein kinase), JNK and NFκB pathways to determine which plays a major role in stimulating TNFα secretion in human HEM (melanocytes) and MM96L (melanoma) cells. MM96L cells exhibited 3.5-fold higher p38 activity than HEM cells at 5 min following UVA + B radiation and 1.6-fold higher JNK activity at 15–30 min following UVB+A radiation, while NFκB was minimally activated in both cells. Irradiated HEM cells had the greatest fold of TNFα secretion (UVB: 109-fold, UVA + B: 103-fold & UVB+A: 130-fold) when co-exposed to IL1α. The p38 inhibitor, SB202190, inhibited TNFα release by 93% from UVB-irradiated HEM cells. In the UVB-irradiated MM96L cells, both SB202190 and sulfasalazine (NFκB inhibitor) inhibited TNFα release by 52%. Although, anisomycin was a p38 MAPK activator, it inhibited TNFα release in UV-irradiated cells. This suggests that UV-mediated TNFα release may occur via different p38 pathway intermediates compared to those stimulated by anisomycin. As such, further studies into the functional role p38 MAPK plays in regulating TNFα release in UV-irradiated melanocyte-derived cells are warranted.  相似文献   

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Although slagging coal gasifiers have served the commercial systerrrs of electricity and chemical fertilizer productions for more than ten years, refractory service life still is a critical factor for gasifier availability. Some investigations were attracted, focusing on coal slag attack on high chromia refractories. A general introduction is made in order to have further uruterstandlng about slag corrosion in coal gasification environment. Microstructural deterioration and wear process of high chromia refractory in slagging gasifiers are discussed.  相似文献   

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This review article focuses on the development of atmospheric freeze drying (AFD): technological aspects, product possibilities, physical properties of products, drying kinetics, modeling, and simulation. The main motivation for developing atmospheric freeze drying as a new drying technology is the desire to reduce the energy consumption compared to vacuum freeze drying while maintaining a high product quality. One technical solution of atmospheric freeze drying is a combined atmospheric freeze drying and heat pump system with new environmentally friendly refrigerants. Temperature programs make it possible to customize products with desired qualities and properties, like retained color, instant properties, aroma, and nutritional value.  相似文献   

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In this study, 4′,7-diacetoxyapigenin [4-(7-acetoxy-5-hydroxy-4-oxo-4H-chromen-2-yl) phenyl acetate] was synthesized for the first time. Its chemical structure was identified by UV, ESI-MS, 1H and 13C-NMR. It could inhibit the proliferation of Hep G2 cells in a dose-dependent manner and induce the significant increase of the G0/G1 cell population. After treatment by 4′,7-diacetoxyapigenin, phosphatidylserine of Hep G2 cells could significantly translocate to the surface of the membrane. The increase of an early apoptotic population was observed by both annexin-FITC and PI staining. It was concluded that 4′,7-diacetoxyapigenin not only induced cells to enter into apoptosis, but also affected the progress of the cell cycle.  相似文献   

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《Drying Technology》2013,31(9):1669-1698
Abstract

This article examines the state-of-the art on aerodynamic separation and drying of leaves and stems. Relevant aerodynamic and drying characteristics of alfalfa leaves and stems, important in the design and functional performance evaluation of appropriate drying and separation systems, are presented. General features and design parameters of rotary drum dryers are discussed. A new efficient approach to combined drying and separation in a rotary drum dryer is described in which fresh or pre-wilted alfalfa mixture is dried at a moderate temperature, and in the same operation the dry leaf fraction is aerodynamically separated from the stem fraction. Preliminary test data obtained from the dryer indicated that the separated product stream had comparatively high leaf purity, confirming the feasibility of the new approach.  相似文献   

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Purification of municipal wastewater generates huge amounts of sewage sludge, which contains large quantities of water, biomass, and extracellular polymeric substances. It is widely known that sewage sludge usually has a poor dewaterability. A large amount of water in sludge directly translates into high transport and handling costs; therefore, sludge treatment and disposal usually requires over 50% of the operation budget for wastewater treatment plants. The application of a low electric field through the sludge segment, called electro-dewatering, is considered to improve the liquid–solid separation, resulting in low water content in the sludge cake. However, prediction of dewatering enhancement for sewage sludge, in particular, offers a challenge due to variations in sludge pretreatment practices and the lack of harmonized testing methodologies. In this review article, the aspects that have an effect on sewage sludge electro-dewatering and its feasibility are discussed in the light of recent technological developments. It was found that electro-dewatering has several potential benefits, such as removal of pathogens, reduction in energy and transportation costs, and prevention of filter fouling.  相似文献   

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The main water channel of the brain, aquaporin-4 (AQP4), is one of the classical water-specific aquaporins. It is expressed in many epithelial tissues in the basolateral membrane domain. It is present in the membranes of supporting cells in most sensory organs in a specifically adapted pattern: in the supporting cells of the olfactory mucosa, AQP4 occurs along the basolateral aspects, in mammalian retinal Müller cells it is highly polarized. In the cochlear epithelium of the inner ear, it is expressed basolaterally in some cells but strictly basally in others. Within the central nervous system, aquaporin-4 (AQP4) is expressed by cells of the astroglial family, more specifically, by astrocytes and ependymal cells. In the mammalian brain, AQP4 is located in high density in the membranes of astrocytic endfeet facing the pial surface and surrounding blood vessels. At these locations, AQP4 plays a role in the maintenance of ionic homeostasis and volume regulation. This highly polarized expression has not been observed in the brain of fish where astroglial cells have long processes and occur mostly as radial glial cells. In the brain of the zebrafish, AQP4 immunoreactivity is found along the radial extent of astroglial cells. This suggests that the polarized expression of AQP4 was not present at all stages of evolution. Thus, a polarized expression of AQP4 as part of a control mechanism for a stable ionic environment and water balanced occurred at several locations in supporting and glial cells during evolution. This initially basolateral membrane localization of AQP4 is shifted to highly polarized expression in astrocytic endfeet in the mammalian brain and serves as a part of the neurovascular unit to efficiently maintain homeostasis.  相似文献   

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Tree nuts are rich in macro and micronutrients, phytochemicals, tocopherols and phenolic compounds. The development of nut spreads would potentially increase the food uses of nuts and introduce consumers with a healthier, non-animal breakfast snack food. Nut spreads are spreadable products made from nuts that are ground into paste. Roasting and milling (particle size reduction) are two important stages for the production of nut spreads that affected the textural, rheological characteristic and overall quality of the nut spread. Textural, color, and flavor properties of nut spreads play a major role in consumer appeal, buying decisions and eventual consumption. Stability of nut spreads is influenced by its particle size. Proper combination of ingredients (nut paste, sweetener, vegetable oil and protein sources) is also required to ensure a stable nut spread product is produced. Most of the nut spreads behaved like a non-Newtonian pseudo-plastic fluid under yield stress which help the producers how to start pumping and stirring of the nut spreads. Similar to other high oil content products, nut spreads are susceptible to autoxidation. Their oxidation can be controlled by application of antioxidants, using processing techniques that minimize tocopherol and other natural antioxidant losses.  相似文献   

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The aim of this study was to analyze the suitability of pluripotent stem cells derived from the amnion (hAECs) as a potential cell source for revitalization in vitro. hAECs were isolated from human placentas, and dental pulp stem cells (hDPSCs) and dentin matrix proteins (eDMPs) were obtained from human teeth. Both hAECs and hDPSCs were cultured with 10% FBS, eDMPs and an osteogenic differentiation medium (StemPro). Viability was assessed by MTT and cell adherence to dentin was evaluated by scanning electron microscopy. Furthermore, the expression of mineralization-, odontogenic differentiation- and epithelial–mesenchymal transition-associated genes was analyzed by quantitative real-time PCR, and mineralization was evaluated through Alizarin Red staining. The viability of hAECs was significantly lower compared with hDPSCs in all groups and at all time points. Both hAECs and hDPSCs adhered to dentin and were homogeneously distributed. The regulation of odontoblast differentiation- and mineralization-associated genes showed the lack of transition of hAECs into an odontoblastic phenotype; however, genes associated with epithelial–mesenchymal transition were significantly upregulated in hAECs. hAECs showed small amounts of calcium deposition after osteogenic differentiation with StemPro. Pluripotent hAECs adhere on dentin and possess the capacity to mineralize. However, they presented an unfavorable proliferation behavior and failed to undergo odontoblastic transition.  相似文献   

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Atmospheric Pressure Plasma (APP) is being used widely in a variety of biomedical applications. Extensive research in the field of plasma medicine has shown the induction of DNA damage by APP in a dose-dependent manner in both prokaryotic and eukaryotic systems. Recent evidence suggests that APP-induced DNA damage shows potential benefits in many applications, such as sterilization and cancer therapy. However, in several other applications, such as wound healing and dentistry, DNA damage can be detrimental. This review reports on the extensive investigations devoted to APP interactions with DNA, with an emphasis on the critical role of reactive species in plasma-induced damage to DNA. The review consists of three main sections dedicated to fundamental knowledge of the interactions of reactive oxygen species (ROS)/reactive nitrogen species (RNS) with DNA and its components, as well as the effects of APP on isolated and cellular DNA in prokaryotes and eukaryotes.  相似文献   

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A distillery industry which represents an important segment of the world economy is amongst the highly polluting industries after the paper industries. Spent wash (SW) generated from distilleries have a very high chemical oxygen demand (COD) (i.e., 20,000–50,000 mg/dm3) and biological oxygen demand (BOD) (i.e., 7000–50,000 mg/dm3), while the COD and BOD values depend on the raw material used. If it is discharged to water-receiving bodies without treatment, it may damage the aquatic system. Apart from causing water pollution, unpleasant odor of effluent spreads several kilometers around the distillery. The untreated/partially treated effluent if discharged in the land makes it infertile. Environmental issues have become one of the important factors controlling the growth of distillery industries. Therefore, it is very necessary to investigate the efficient and cost-effective processes to treat SW. The physicochemical processes are still not being applied in many distilleries, which are possible to have feasible remediation technologies to combat environmental pollution. In the present review article, different physicochemical technologies like coagulation, flocculation, electrocoagulation, thermolysis, wet oxidation, and adsorption as well as biological treatment for the wastewater of distillery industries have been presented. The distillery wastewater management is also discussed.  相似文献   

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Rajput  Priti J.  Bhandari  Sheetal U.  Wadhwa  Girish 《SILICON》2022,14(15):9195-9210
Silicon - This review describes an emerging field of electronics devices; electron spin exploitation use for a further degree of freedom incorporation to charge state, with the significant feature...  相似文献   

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Jute fiber is an important agricultural product. It is one of the most common natural fibers in Third World countries such as India, China, Bangladesh, etc. The jute industry has special importance in the economy of India and continues to be a major traditional earner of foreign exchange. However, it is facing tough competition from the synthetic fibers. Jute fibers find use in sophisticated fields like decorative and furnishing materials such as lamp shades, wall covers, curtains, upholsteries, etc. Today it is the least expensive fiber of mass consumption, at only a fraction of the cost of glass fibers; in terms of volume, jute is now the second most important fiber in the world, next to cotton. In the traditional applications in carpets, ropes, sacks, etc., jute fibers have been partially replaced by synthetic fibers which have some advantages compared to jute. In order to ensure a reasonable return to farmers, nontraditional outlets have to be explored for the fiber. One such avenue is in the area of fiber-reinforced composites.  相似文献   

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