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91.
Neuroblastoma is a common extracranial solid tumour of childhood, responsible for 15% of cancer-related deaths in children. Prognoses vary from spontaneous remission to aggressive disease with extensive metastases, where treatment is challenging. Tumours are thought to arise from sympathoadrenal progenitor cells, which derive from an embryonic cell population called neural crest cells that give rise to diverse cell types, such as facial bone and cartilage, pigmented cells, and neurons. Tumours are found associated with mature derivatives of neural crest, such as the adrenal medulla or paraspinal ganglia. Sympathoadrenal progenitor cells express anaplastic lymphoma kinase (ALK), which encodes a tyrosine kinase receptor that is the most frequently mutated gene in neuroblastoma. Activating mutations in the kinase domain are common in both sporadic and familial cases. The oncogenic role of ALK has been extensively studied, but little is known about its physiological role. Recent studies have implicated ALK in neural crest migration and sympathetic neurogenesis. However, very few downstream targets of ALK have been identified. Here, we describe pathological activation of ALK in the neural crest, which promotes proliferation and migration, while preventing differentiation, thus inducing the onset of neuroblastoma. Understanding the effects of ALK activity on neural crest cells will help find new targets for neuroblastoma treatment.  相似文献   
92.
There is an increased interest, driven by environmental sustainability and food security points of view, in seeking new protein sources as alternatives to replace animal proteins (Day, Trends in Food Science and Technology, 32 , 2016, 25). Pulse proteins, including lentil proteins (LP), are promising good substitutes as the wide variety of functional properties shown by them (Alsohaimy et al., World Journal of Agricultural Sciences, 3 , 2007, 123; Boye et al., Food Research International, 43 , 2010a, 537). Interest in LP has grown due to its high nutritional value, good Leu/Ile and Leu/Lys ratios (1.24–1.98 and 1.08–2.03, respectively) (Urbano et al., Lentil: An Ancient Crop for Modern Times, 2007, 47, Berlin: Springer), high digestibility (~83%) (Barbana & Boye, Food & Function, 4 , 2013, 310), and its potential use in food product applications (Farooq & Boye, Novel Food and Industrial Applications of Pulse Flours and Fractions. Pulse Foods, 1st edn, 2011, Amsterdam: Elsevier Ltd; Aider et al., Journal of Food Research, 1 , 2012, 160; De la Hera et al., LWT – Food Science and Technology, 49 , 2012, 48; Turfani et al., LWT – Food Science and Technology, 78 , 2017, 361). On the other hand, great progress has been made lately to reveal the good functionality of LP such as solubility and emulsifying, foaming and gelation capacities (Avramenko et al., Food Research International, 81 , 2016, 17; Jarpa‐Parra et al., Food Hydrocolloids, 61 , 2016, 903; Primozic et al., Food Chemistry, 237 , 2017, 65). However, the relatively unknown relationship between its molecular structure and functionalities and the lack of knowledge of the impact of the extraction and environmental conditions on those properties has hindered the exploitation of their full potential. This review describes the current knowledge of the LP structure, physical chemistry and functional properties, and its potential role as an ingredient for the development of food grade products. The gap between the current knowledge and what remains to be known is emphasised.  相似文献   
93.
Polybetaines, that have moieties bearing both cationic (quaternary ammonium group) and anionic groups (carboxylate, sulfonate, phosphate/phosphinate/phosphonate groups) situated in the same structural unit represent an important class of smart polymers with unique and specific properties, belonging to the family of zwitterionic materials. According to the anionic groups, polybetaines can be divided into three major classes: poly(carboxybetaines), poly(sulfobetaines) and poly(phosphobetaines). The structural diversity of polybetaines and their special properties such as, antifouling, antimicrobial, strong hydration properties and good biocompatibility lead to their use in nanotechnology, biological and medical fields, water remediation, hydrometallurgy and the oil industry. In this review we aimed to highlight the recent developments achieved in the field of biomedical applications of polybetaines such as: antifouling, antimicrobial and implant coatings, wound healing and drug delivery systems.  相似文献   
94.
In this article, we propose new control charts for monitoring the mean vector and the covariance matrix of bivariate processes. The traditional tools used for this purpose are the T 2 and the |S| charts. However, these charts have two drawbacks: (1) the T 2 and the |S| statistics are not easy to compute, and (2) after a signal, they do not distinguish the variable affected by the assignable cause. As an alternative to (1), we propose the MVMAX chart, which only requires the computation of sample means and sample variances. As an alternative to (2), we propose the joint use of two charts based on the non-central chi-square statistic (NCS statistic), named as the NCS charts. Once the NCS charts signal, the user can immediately identify the out-of-control variable. In general, the synthetic MVMAX chart is faster than the NCS charts and the joint T 2 and |S| charts in signaling processes disturbances.  相似文献   
95.
The effect of the addition of flaxseed gum on the physicochemical properties of whey protein-stabilized (WPI) oil-in-water emulsions at pH 3.5 was investigated. Two different varieties (Emerson and McDuff) were tested at concentrations ranging from 0% to 0.33% (w/v), by measuring droplet size, ζ-potential, phase separation behavior, microstructure and apparent viscosity. With addition of flaxseed gum the ζ-potential of the droplets decreased from around +30 mV to a negative value (−10 mV) at concentrations >0.2%. These results indicated that the negatively charged polysaccharide fraction from flaxseed interacted with the protein adsorbed at the interface. An increase in apparent particle size was also noted with increasing flaxseed concentration, with destabilization becoming visually evident at concentrations higher than 0.1% (w/v). Microscopy, rheological data and size distribution analysis demonstrated for the first time that flaxseed gum interacts with protein-stabilized oil droplets at low pH, causing bridging flocculation. No significant differences were noted between flaxseed gums extracted from the Emerson and McDuff varieties. This research demonstrated that the electrostatic interactions between flaxseed gums and protein-stabilized emulsions need to be controlled when designing novel acidic beverages containing these polysaccharides.  相似文献   
96.
Based on experimental data collected from the literature, a group contribution method for estimating the melting points of imidazolium-, pyridinium-, pyrrolidinium-, ammonium-, phosphonium-, and piperidinium-based ionic liquids (ILs) with common anions is proposed. The method considers the contributions of ionic groups and methylene groups, as additive parameters, and two nonadditive characteristic geometric parameters of cations such as symmetry and flexibility. A total of 293 data points for 136 ILs were used in this study. The average relative deviation and the average absolute deviation of the proposed model are 7.8% and 22.6 K, respectively. It is concluded that the proposal is useful for the prediction of the melting points for a wide range of ILs.  相似文献   
97.
Mechanochemical synthesis of bismuth selenides (BiSe, Bi2Se3) was performed by high-energy milling of bismuth and selenium powders in a planetary ball mill. The particle size distribution and the specific surface area of Bi/Se and 2Bi/3Se powder mixtures were analysed at increasing milling time. The products were characterized by X-ray diffraction, differential scanning calorimetry and transmission electron microscopy. The presence of bismuth selenide phases was observed after only 1?min of milling and full conversion into hexagonal BiSe phase (nevskite) and rhombohedral Bi2Se3 phase (paraguanajuatite) was reached after 10?min of milling. The nanocrystalline nature of both mechanochemically synthesised bismuth selenides was confirmed and their optical band gap energies were obtained on the basis of the recorded absorption spectra in UV–Vis spectral region.  相似文献   
98.
We report on the quantum correlations dissipative dynamics followed by coupled superconducting flux qubits. The coupling between the superconducting quantum register and the reservoir is described by two different mechanisms: collective and independent decoherence. By means of the Bloch?CRedfield formalism, we solve the quantum master equation and show that coupling under collective quantum noise is more robust to decoherence. This result is demonstrated for different flux qubit initial preparations, taking into account the influence due to external fields and temperature. Furthermore, we compute the entanglement and the quantum discord dissipative dynamics as controlled by external parameters. We show that the discord is more robust against decoherence effects. This fact could be harnessed in the realization of quantum computing tasks that do not need to invoke entanglement in their implementation.  相似文献   
99.
The aim of the study was to determine if natural and artificial casings (ovine, porcine, bovine, collagen, and cellulose casings), serve as carriers for the application of the bacteriocin sakacin G produced by Lactobacillus curvatus ACU‐1. Mode of action of the cell‐free supernatant (CFS) containing the bacteriocin was also studied to determine whether Listeria monocytogenes inhibition could be tantamount to Listeria innocua one. Cylindrical vessels were filled with sterile meat emulsion and were wrapped with the different casings. Half the systems were treated with the CFS containing sakacin G, while the other half was taken as control systems. All systems were inoculated with L. innocua ATCC 33090. L. innocua was able to grow on all the studied casings. Collagen casing treated with CFS inhibited Listeria growth. A bacteriostatic effect was observed in the systems with porcine, ovine, bovine and cellulosic casings treated with CFS. The bacteriocin maintained its activity until the end of the trial. All casings were widely promising as antimicrobial application supports, being effective carriers to be used in a wide range of meat products.

Practical applications

Based on its advantageous characteristics, bacteriocins attracted considerable interest as natural food preservatives to extend shelf life and safety of meat and meat products. The application of sakacin G produced by Lactobacillus curvatus ACU‐1 on different natural and artificial casings would allow the preservation of a wide range of meat products that are stuffed into them, such as several types of sausages, wiener, salami, and mortadella, among others. The major advantage relies on its application, since it is not necessary to modify the production process or add extra wrappings to support the antimicrobial substance.  相似文献   
100.
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