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941.
    
As extracellular vesicles (EVs) have become a prominent topic in life sciences, a growing number of studies are published on a regular basis addressing their biological relevance and possible applications. Nevertheless, the fundamental question of the true vesicular nature as well as possible influences on the EV secretion behavior have often been not adequately addressed. Furthermore, research regarding endothelial cell-derived EVs (EndoEVs) often focused on the large vesicular fractions comprising of microvesicles (MV) and apoptotic bodies. In this study we aimed to further extend the current knowledge of the influence of pre-isolation conditions, such as cell density and conditioning time, on EndoEV release from human umbilical vein endothelial cells (HUVECs). We combined fluorescence nanoparticle tracking analysis (NTA) and the established fluorescence-triggered flow cytometry (FT-FC) protocol to allow vesicle-specific detection and characterization of size and surface markers. We found significant effects of cell density and conditioning time on both abundance and size distribution of EndoEVs. Additionally, we present detailed information regarding the surface marker display on EVs from different fractions and size ranges. Our data provide crucial relevance for future projects aiming to elucidate EV secretion behavior of endothelial cells. Moreover, we show that the influence of different conditioning parameters on the nature of EndoEVs has to be considered.  相似文献   
942.
943.
    
We report the synthesis and evaluation of a class of selective multitarget agents for the inhibition of HDAC6, HDAC8, and HDAC10. The concept for this study grew out of a structural analysis of the two selective inhibitors Tubastatin A (HDAC6/10) and PCI-34051 (HDAC8), which we recognized share the same N-benzylindole core. Hybridization of the two inhibitor structures resulted in dihydroxamic acids with benzyl-indole and -indazole core motifs. These substances exhibit potent activity against HDAC6, HDAC8, and HDAC10, while retaining selectivity over HDAC1, HDAC2, and HDAC3. The best substance inhibited the viability of the SK-N-BE(2)C neuroblastoma cell line with an IC50 value similar to a combination treatment with Tubastatin A and PCI-34051. This compound class establishes a proof of concept for such hybrid molecules and could serve as a starting point for the further development of enhanced HDAC6/8/10 inhibitors.  相似文献   
944.
A fluidized bed system combining two circulating fluidized bed reactors is proposed and investigated for chemical looping combustion. Direct hydraulic communication of the two circulating fluidized bed reactors via a fluidized loop seal allows for high rates of global solids circulation and results in a stable solids distribution in the system. A 120 kW fuel power bench scale unit was designed, built, and operated. Experimental results are presented for natural gas as fuel using a nickel‐based oxygen carrier. No carbon was lost to the air reactor under any conditions operated. It is shown from fuel power variations that a turbulent/fast fluidized bed regime in the fuel reactor is advantageous. Despite the relatively low riser heights (air reactor: 4.1 m, fuel reactor: 3.0 m), high CH4 conversion and CO2 yield of up to 98% and 94%, respectively, can be reported for the material tested. © 2009 American Institute of Chemical Engineers AIChE J, 2009  相似文献   
945.

Agriotes pilosellus is a fairly common click beetle species distributed in open deciduous and mixed forests throughout a large area in Europe. To identify its sex pheromone, gland extracts of female beetles were analyzed using gas chromatography-mass spectrometry (GC-MS). The only volatile compounds present in the extracts were geranyl butanoate and (E)-8-hydroxygeranyl dibutanoate in a 1:3 ratio, identified by comparison with synthetic samples. Field experiments revealed a clear attraction of A. pilosellus - males towards traps baited with geranyl butanoate, which could be synergistically enhanced by the factor of almost ten by addition of (E)-8-hydroxygeranyl dibutanoate. The latter compound alone did not show any attractive effect. Both compounds correspond well to the structures known from other Agriotes species and may serve as an effective monitoring tool for entomofaunistic research.

  相似文献   
946.
Silicon - A local perlite mineral (P1) was used to remove the industrial dyes Remazole Brilliant 19 (RB19) and Drimarene Yellow (YD) from an aqueous solution. Prior to any investigation, P1 was...  相似文献   
947.
Two reaction systems based on vanadium nitrogenase were previously shown to reduce CO2 to hydrocarbons: 1) an enzyme‐based system that used both components of V nitrogenase for ATP‐dependent reduction of CO2 to ≤C2 hydrocarbons; and 2) a cofactor‐based system that employed SmI2 to supply electrons to the isolated V cluster for an ATP‐independent reduction of CO2 to ≤C3 hydrocarbons. Here, we report ATP‐independent reduction of CO2 to hydrocarbons by a reaction system comprising EuII DTPA and the VFe protein of V nitrogenase. Combining features of both enzyme‐ and cofactor‐based systems, this system exhibits improved C?C coupling and a broader product profile of ≤C4 hydrocarbons. The C?C coupling does not employ CO2‐derived CO, and it is significantly enhanced in D2O. These observations afford initial insights into the characteristics of this unique reaction and provide a potential template for future design of catalysts to recycle the greenhouse gas CO2 into useful products.  相似文献   
948.
Sodium bis(2‐ethylhexyl) sulfosuccinate (known as AOT) is a commercially available surfactant commonly used in agrochemicals. Besides the principal diester surfactant, the commercial AOT product contains two surface‐active isomeric monoester by‐products, which may influence the surfactant's overall properties. This work investigates whether the purity of the surfactant affects its ability to stabilize an agrochemical formulation. The concentrations of the diester and two monoester impurities in batches of commercial AOT product from several suppliers were determined quantitatively by liquid chromatography–mass spectrometry. The tested batches showed different contents of the monoesters. Samples of a model agrochemical formulation containing the AOT product formed more sediment during storage when the content of monoesters in the surfactant was high. The supplier of an commercial AOT product could be traced by analysis of the monoester content of either the raw product or the aged agrochemical formulation.  相似文献   
949.
In this study, a new process for additive manufacturing (AM) of dense and strong ceramic objects is described. The lithography‐based ceramic manufacturing (LCM) technique is based on the selective curing of a photosensitive slurry by a dynamic mask exposure process. The LCM technique is able to produce strong, dense and accurate alumina ceramics without virtually any geometrical limitations. With over 99.3% of a theoretical alumina density, four‐point bending strength of 427 MPa, and very smooth surfaces, the LCM process distinguishes itself from other AM techniques for ceramics and provides parts with very similar mechanical properties as conventionally formed alumina.  相似文献   
950.
Loss-of-function mutations in the sphingomyelin phosphodiesterase 1 (SMPD1) gene are associated with decreased catalytic activity of acid sphingomyelinase (ASM) and are the cause of the autosomal recessive lysosomal storage disorder Niemann-Pick disease (NPD) types A and B. Currently, >100 missense mutations in SMPD1 are listed in the Human Gene Mutation Database. However, not every sequence variation in SMPD1 is detrimental and gives rise to NPD. We have analysed several alleged SMPD1 missense mutations mentioned in a recent publication and found them to be common variants of SMPD1 that give rise to normal in vivo and in vitro ASM activity. (Comment on Manshadi et al. Int. J. Mol. Sci.2015, 16, 6668–6676).  相似文献   
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