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991.
Mitoxantrone (MTX) is an antineoplastic agent whose use is limited by serious side effects on non‐neoplastic cells. The aim of this study was the development of a new drug release system using an ionotropic gelation technique for microencapsulation of MTX in chitosan–carboxymethylinulin nanoparticles (CCInp), followed by evaluation of their cytotoxic effects on neoplastic MDA‐MB‐231 and non‐neoplastic NIH3T3 cell lines. The CCInp were prepared through a new reliable method for easy functionalization of both inulin and chitosan. Both unloaded and drug‐loaded nanoparticles were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS) and showed a spherical morphology with an average hydrodynamic diameter between 40 and 80 nm. Both nanoparticles were stable and easily degraded by lysozyme. MTX‐loaded nanoparticles led to a greater mortality of MDA‐MB‐231 relative to free drug due to the ability of the nanoparticles to accumulate preferentially in neoplastic cells. The developed drug release system retains the ability to kill MDA‐MB‐231 cells in vitro, improving the survival of NIH3T3 cells.  相似文献   
992.
Hulled, or ancient, wheats were the earliest domesticated wheats by mankind and the ancestors of current wheats. Their cultivation drastically decreased during the 1960s; however, the increasing demand for a healthy and equilibrated diet led to rediscovering these grains. Our aim was to use a non-targeted metabolomic approach to discriminate and characterize similarities and differences between ancient Triticum varieties. For this purpose, 77 hulled wheat samples from three different varieties were collected: Garfagnana T. turgidum var. dicoccum L. (emmer), ID331 T. monococcum L. (einkorn) and Rouquin T. spelta L. (spelt). The ultra high performance liquid chromatography coupled to high resolution tandem mass spectrometry (UHPLC-QTOF) metabolomics approach highlighted a pronounced sample clustering according to the wheat variety, with an excellent predictability (Q2), for all the models built. Fifteen metabolites were tentatively identified based on accurate masses, isotopic pattern, and product ion spectra. Among these, alkylresorcinols (ARs) were found to be significantly higher in spelt and emmer, showing different homologue composition. Furthermore, phosphatidylcholines (PC) and lysophosphatidylcholines (lysoPC) levels were higher in einkorn variety. The results obtained in this study confirmed the importance of ARs as markers to distinguish between Triticum species and revealed their values as cultivar markers, being not affected by the environmental influences.  相似文献   
993.
The design, synthesis, spectroscopic and photochemical properties, and biological evaluation of a novel molecular hybrid that is able to deliver nitric oxide (NO) into mitochondria are reported. This molecular conjugate unites a tailored o‐CF3p‐nitroaniline chromophore, for photo‐regulated NO release, and a rhodamine moiety, for mitochondria targeting, in the same molecular skeleton via an alkyl spacer. A combination of steady‐state and time‐resolved spectroscopic and photochemical experiments demonstrate that the two chromogenic units preserve their individual photophysical and photochemical properties in the conjugate quite well. Irradiation with violet light triggers NO release from the nitroaniline moiety and photoionization in the rhodamine center, which also retains considerable fluorescence efficiency. The molecular hybrid preferentially accumulates in the mitochondria of A549 lung adenocarcinoma cells where it induces toxicity at a concentration of 1 μm , exclusively upon irradiation. Comparative experiments, carried out with ad‐hoc‐synthesized model compounds, suggest that the phototoxicity observed at such a low concentration is probably not due to NO itself, but rather to the formation of the highly reactive peroxynitrite that is generated from the reaction of NO with the superoxide anion.  相似文献   
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Green manure mixtures including legumes and forbs can help to increase N availability in organic arable systems. Anaerobic digestion of green manures may provide ammonium rich digestate, which can be redistributed as fertilizer. The aim of this study was to investigate the effect of plant species composition, cutting strategy and anaerobic digestion on the N fertilizer replacement value (NFRV) of different green manures. Digestates obtained from silages of pure stand lucerne (four cuts/year) and a mixture including lucerne, grass and forbs (two or four cuts/year) were used to fertilize winter wheat (surface banding) and spring barley (injection). In general, NFRV was 46–173% higher in spring barley than winter wheat, due to the different application method and timing, which reflect the common practices in Denmark. NFRV of digestates were 25–63% higher than the corresponding silages, with the largest increase with the most fibrous material (mixture at two cuts/year). Total N concentration (DM based) in the silages largely explained NFRV of the digestates. To obtain NFRV above 60%, total N concentration of silage should exceed 3.5 g 100 g?1 DM, achievable with silages from four-cut strategies. Silages of plant materials with different composition and N content may be similar in terms of biomethane production, but the fertilizer value of the digestates varies considerably depending on total N concentration.  相似文献   
998.
This paper describes how people make sense of and use constellations of technologies in a nomadic setting, and it illustrates how maintaining and orchestrating a variety of applications and devices becomes an essential part of nomadic practices. The data were collected over a period of 3 years at a technical university by means of two field studies. Particular attention is drawn to how the situated orchestration of devices and applications within a group’s constellation reflects university students’ concern to manage their projects at a number of locations, as well as issues of time and circulation of resources. The analysis brings into focus how constellations of technologies emerge and dissolve within collaborative ensembles that only exist for the duration of a project, and how this can cause appropriation issues within groups.  相似文献   
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Mobile Networks and Applications - Interconnected computational devices in the Internet of Things (IoT) context make possible to collect real-time data about a specific environment. The IoT...  相似文献   
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