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31.
Neutrophils are a type of granulocyte important in the “first line of defense” of the innate immune system. Upon activation, they facilitate the destruction of invading microorganisms by the production of superoxide radicals, as well as the release of the enzymatic contents of their lysozymes. These enzymes include specific serine proteases: cathepsin G, neutrophil elastase, proteinase 3, as well as the recently discovered neutrophil serine protease 4 (NSP4). Under normal conditions, the proteolytic activity of neutrophil proteases is tightly regulated by endogenous serpins; however, this mechanism can be subverted during tissue stress, thereby resulting in the uncontrolled activity of serine proteases, which induce chronic inflammation and subsequent pathology. Herein, we describe the development of low‐molecular‐weight activity‐based probes that specifically target the active sites of neutrophil proteases.  相似文献   
32.
Ni/La–Al2O3 and Ni/Ce–Al2O3 catalysts with a small amount of promoters intended for prereforming of LNG were characterized by XRF, N2 adsorption-desorption, XRD, H2 chemisorption, HRTEM and XPS. The catalytic activity was evaluated in methane steam reforming both in the kinetic and diffusion regime, at temperatures characteristic of pre-reforming. Carbonaceous deposit was analysed by TPO-MS method. The nature and location of the coke were studied by HRTEM.La or Ce addition into Ni–Al system causes the increase of the active surface area of Ni by enhancing its dispersion. Studies at kinetic regime have shown that the promoted catalysts have almost twice the activity than reference Ni–Al catalyst. This effect was not confirmed by measurements in the diffusion regime on whole catalyst tablets. Almost identical textural properties of catalysts and diffusive limitations related to them but not the catalytic properties of the material itself appeared to be crucial factors. The presence of La (but not Ce) causes a significant increase in resistance to coking.  相似文献   
33.
MXenes are novel 2-D materials which have been extensively investigated for use in advanced biocomposites, water purification, biosensors, bioimaging and antibacterial systems. However, the knowledge associated with the mechanism of cytotoxic response is still limited to lack of verification against 3D spheroid-type cultures. Herein, we present a report on the in vitro cytotoxicity of Ti2CTx MXene against cervical cancer cell lines (HeLa) in a form of 3D spheroid with comparison to 2D cell culture system. Ti2CTx MXenes can be characterized by their multi-layered structure that is produced by the efficient elimination of Al and appearance of the surface functional groups. The biological results with 2D and 3D HeLa indicated that the Ti2CTx MXene was moderately cytotoxic to cells and the cytotoxicity was dose dependent. Our results showed that the toxicity of MXenes is potentially due to direct contact of the Ti2CTx MXene with the cell membrane wall. The Raman spectra suggested that the Ti2CTx MXenes interfered with the cytoplasmic proteins’ conformation and the surrounding microenvironment. This inherently modified the biochemistry of the cell membrane and caused cell apoptosis. This paper contributes to the pool of knowledge regarding the biocompatibility and biophysical properties of Ti2CTx MXene.  相似文献   
34.
Psoriasis is a chronic, systemic inflammatory disease with a genetic background that involves almost 3% of the general population worldwide. Approximately, 70–90% of patients with psoriasis suffer from pruritus, an unpleasant sensation that provokes a desire to scratch. Despite the enormous progress in understanding the mechanisms that cause psoriasis, the pathogenesis of psoriasis-related pruritus still remains unclear. In order to improve patients’ quality of life, development of more effective and safer antipruritic therapies is necessary. In turn to make it possible, better understanding of complexed and multifactorial pathogenesis of this symptom is needed. In this article we have systematized the current knowledge about pruritus origin in psoriasis.  相似文献   
35.
We have examined endothelial cell density before and 3, 6, 12 months after extracapsular cataract extraction with intraocular lens implantation (posterior chamber) in diabetic patients and in non-diabetics. We have not found statistically significant differences between the mean loss of endothelial cells due to surgery in diabetic and non-diabetic patients.  相似文献   
36.
Margarines and spreads contribute greatly to the intake of saturated and trans fats in the diet. Therefore, the objective of this work was to produce margarines using the oleogel technology and to verify the physical, thermal, oxidative, and sensorial properties of this product during six months of shelf life, comparing it with commercial margarine. When compared with commercial margarine, the oleogel margarine showed similar color results. Due to the different structural shape, the results of microstructure and the melting curve were differentiated, but this indicated a structure more resistant to temperature oscillations and an overall softer product. However, the sensorial difference between the samples was easily detected by the consumers, mainly with respect to the parameters of taste, texture, and overall impression. It was concluded that it is possible to produce margarines using the oleogel technology, which display good physical properties, similar shelf life, and improved nutritional characteristics.  相似文献   
37.
The influence of Cr2O3 on properties of the Cr2O3/MgF2 catalysts obtained by impregnation and precipitation-deposition is described. The IR technique enabled monitoring of changes in the structure of the MgF2 surface after introducing chromium ions. Tetrahedral chromium complexes as well as structures of Cr3O3 type were observed. The deposited species generated the Lewis and BrØnsted acidity which in turn was responsible for the catalytic activity in the reactions of 2-propanol decomposition, butène double bond isomerization, cumene cracking, dehydrogenation of cyclohexane and decomposition of methyl alcohol.  相似文献   
38.
Vanadium oxides supported on magnesium fluoride obtained by the impregnation and the precipitation-deposition method have been studied by IR spectroscopy. The adsorption of pyridine indicated the presence of Lewis acid centers on the impregnated samples, whereas on the samples prepared by precipitation both Lewis and Brønsted centers have been observed. From the adsorption coefficients of the 1540 cm–1 (Brønsted site) and 1445 cm–1 (Lewis site) bands the numbers of both sites have been estimated. The hydroxyl groups bound in the chains of the (VO3)n tetrahedra or those in the trigonal pyramids VO5 are believed to be responsible for the protonic centers, whereas the aprotonic centers occur at the ionic vanadium with coordinatively unsaturated spheres.  相似文献   
39.
The stretch zone width (SZW) data for 15‐5PH steel CTOD specimens fractured at ?150°C to + 23°C temperature were measured based on focused images and 3D maps obtained by extended depth‐of‐field reconstruction from light microscopy (LM) image stacks. This LM‐based method, with a larger lateral resolution, seems to be as effective for quantitative analysis of SZW as scanning electron microscopy (SEM) or confocal scanning laser microscopy (CSLM), permitting to clearly identify stretch zone boundaries. Despite the worst sharpness of focused images, a robust linear correlation was established to fracture toughness (KC) and SZW data for the 15‐5PH steel tested specimens, measured at their center region. The method is an alternative to evaluate the boundaries of stretched zones, at a lower cost of implementation and training, since topographic data from elevation maps can be associated with reconstructed image, which summarizes the original contrast and brightness information. Finally, the extended depth‐of‐field method is presented here as a valuable tool for failure analysis, as a cheaper alternative to investigate rough surfaces or fracture, compared to scanning electron or confocal light microscopes. Microsc. Res. Tech. 75:1155–1158, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
40.
A collection of lactic acid bacteria isolated from both mayonnaise-based products and raw materials used to manufacture them was tested for antimicrobial activity. Out of 144 strains (97 lactobacilli, 23 lactococci and 24 enterococci) only three supernatants of Enterococcus spp. strains (EN3, EN14 and EN15) exhibited activity against lactobacilli and lactococci. The supernatant of the strain EN3 exclusively inhibited the growth of Bacillus cereus and Listeria monocytogenes. Enterococcus strains EN3, EN14 and EN15 produced thermostable bacteriocins, which had antibacterial activity.  相似文献   
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