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The biorelevant PyFALGEA oligopeptide ligand, which is selective towards the epidermal growth factor receptor (EGFR), has been successfully employed as a substrate in magnetic resonance signal amplification by reversible exchange (SABRE) experiments. It is demonstrated that PyFALGEA and the iridium catalyst IMes form a PyFALGEA:IMes molecular complex. The interaction between PyFALGEA:IMes and H2 results in a ternary SABRE complex. Selective 1D EXSY experiments reveal that this complex is labile, which is an essential condition for successful hyperpolarization by SABRE. Polarization transfer from parahydrogen to PyFALGEA is observed leading to significant enhancement of the 1H NMR signals of PyFALGEA. Different iridium catalysts and peptides are inspected to discuss the influence of their molecular structures on the efficiency of hyperpolarization. It is observed that PyFALGEA oligopeptide hyperpolarization is more efficient when an iridium catalyst with a sterically less demanding NHC ligand system such as IMesBn is employed. Experiments with shorter analogues of PyFALGEA, that is, PyLGEA and PyEA, show that the bulky phenylalanine from the PyFALGEA oligopeptide causes steric hindrance in the SABRE complex, which hampers hyperpolarization with IMes. Finally, a single-scan 1H NMR SABRE experiment of PyFALGEA with IMesBn revealed a unique pattern of NMR lines in the hydride region, which can be treated as a fingerprint of this important oligopeptide.  相似文献   
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Primary ciliary dyskinesia (PCD) is a rare disease with autosomal recessive inheritance, caused mostly by bi-allelic gene mutations that impair motile cilia structure and function. Currently, there are no causal treatments for PCD. In many disease models, translational readthrough of premature termination codons (PTC-readthrough) induced by aminoglycosides has been proposed as an effective way of restoring functional protein expression and reducing disease symptoms. However, variable outcomes of pre-clinical trials and toxicity associated with long-term use of aminoglycosides prompt the search for other compounds that might overcome these problems. Because a high proportion of PCD-causing variants are nonsense mutations, readthrough therapies are an attractive option. We tested a group of chemical compounds with known PTC-readthrough potential (ataluren, azithromycin, tylosin, amlexanox, and the experimental compound TC007), collectively referred to as non-aminoglycosides (NAGs). We investigated their PTC-readthrough efficiency in six PTC mutations found in Polish PCD patients, in the context of cell and cilia health, and in comparison to the previously tested aminoglycosides. The NAGs did not compromise the viability of the primary nasal respiratory epithelial cells, and the ciliary beat frequency was retained, similar to what was observed for gentamicin. In HEK293 cells transfected with six PTC-containing inserts, the tested compounds stimulated PTC-readthrough but with lower efficiency than aminoglycosides. The study allowed us to select compounds with minimal negative impact on cell viability and function but still the potential to induce PTC-readthrough.  相似文献   
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The purpose of this study was to evaluate the influence of preparation/storage conditions on the sorption, solubility, and mass changes of new proposed hydroxyapatite‐containing resin‐based composites. Seventy cylindrical samples of composite were prepared according to the ISO 4049 and stored in different storage solutions (distilled water, artificial saliva, 10% ethanol, 3% acetic acid, heptane, tea, and coffee) for 7, 14, and 28 days at 37°C. Principal component analysis and analysis of the variance were used to determine the impact of the preparation and storage conditions (e.g., curing time, storage time, and type of storage solution) on the changes of stability of examined material. Sorption, solubility, and mass changes of examined samples were specified. The tendency of these changes depending on the curing time, storage time, and type of storage solutions were presented. Due to the observed behavior, three groups of storage solutions were distinguished: “aqueous,” acidic, and hydrophobic (“fat”) solutions. Investigated properties changed in different way, characteristic for each of the above groups. No general tendency of the influence of storage and curing time was observed. The type of storage solution has the greatest impact on the sorption, solubility, and mass changes of examined material. The influence of the curing and storage time may be neglected. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39856.  相似文献   
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This paper represents the elements and the use of the upgraded simulation system, developed in the last half decade for ?tore Steel billet caster. The simulation system is used in the context of the state-of-the-art automation and information of the twenty-five year-old three-strand Concast billet continuous caster for dimensions square 140 and 180 mm with the capacity of 160,000 tons/year. The simulation system is used in the off-line and on-line modes. The off-line mode is used in order to set the proper process parameters and to calculate the temperature field, macrosegregation, and grain structure of the strand. It is also used to calculate the changes in the caster design such as the secondary cooling and the position of the SEN. The on-line model is used in automatic casting control system. The paper represents an update of our BHM publication of 2005 (Application of Continous Casting Simulation at ?tore Steel, BHM, Vol. 150, No. 9, 300–306).  相似文献   
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Using data from the National Educational Panel Study of 2009/2010, this paper investigates the correlation between regional training supply and employees’ training participation. Controlling for other regional factors such as the local unemployment rate, the educational level, the population density and the regional industry composition, the results indicate that training participation is significantly higher in regions with many firms in the training supply market. The predictive power of the other regional factors is rather minor.  相似文献   
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The dependence of the depth of cure (DOC) and degree of conversion (DC) on the depth of experimental and commercial materials were determined according to ISO 4049 procedure and with the use of Raman spectroscopy, respectively. Moreover, an attempt was made to find the correlation between the DOC and DC and the depth of the material. The hypothesis was that curing time recommended by the manufacturers is appropriate for curing both commercial and experimental materials to achieve comparable values of the examined properties. The impact of the filler characteristic was clearly observed. The longer curing time provides a deeper curing (DOC values) and higher reaction rate (DC); however, the dependence between the DC values and DOC values was not visible. Instead, a logarithmic trend in the relation of the DOC and curing time was clearly observed. The results of this study suggest that the experimental materials give some hope for potential clinical applications and should be further investigated. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42812.  相似文献   
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Quality and safety parameters of Atlantic bonito gravad during 42 days of storage at 7 ± 1 °C were analysed using monitoring sensory quality, microbial contamination, nucleotide degradation products, biogenic amines (BA), trimethylamine (TMA) and thiobarbituric acid reactive substances (TBARS). The shelf‐life of vacuum packed Atlantic bonito gravad was found to be 28 days. Total viable count (TVC) did not exceed 6 log CFU g?1. Malonodialdehyde (MDA) content did not surpass 10 mg kg?1. Nine biogenic amines were detected. Histamine level at the end of the storage was 355.3 mg kg?1. TMA increased from 53.9 to 619.1 mg kg?1. Among indicators based on the products of nucleotide degradation, the H value is best correlated with the sensory assessment. It can be concluded that the storage temperature of bonito gravad must be below 7 °C to prevent the threat to safety and quality posed by biogenic amines, especially histamine.  相似文献   
10.
We investigated both the distribution of protein, ash and starch in legume (chickpeas, smooth and wrinkled peas) cotyledons, and the soaking and cooking characteristics, including gelatinization and retrogradation, of the starch. There were large differences in composition between different types of legumes and also between the outer and inner parts of legume cotyledons. Wrinkled peas exhibited much higher water absorption during prolonged soaking and there were higher hardness value determined for cooked seeds compared with chickpeas and smooth peas. While the hardness of cooked seeds decreased continuously as cooking time increased to 110 min, all legume starch was fully gelatinized after cooking for 70 min.  相似文献   
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