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Objective: The study aimed to summarize the morphological characteristics of low-grade gastric intraepithelial neoplasia (LGIN) and explore its outcomes and risk factors. Additionally, it aimed to screen the core different expression genes (DEGs) of high-grade gastric intraepithelial neoplasia (HGIN) using bioinformatics methods to identify biomarkers for early gastric cancer outcomes. Methods: The clinical and pathological data of 449 patients with LGIN in the endoscopy center of the Second Hospital of Hebei Medical University from June 2013 to September 2018 were collected for retrospective analysis. The GSE130823 and GSE55696 data sets were selected from the Gene Expression Omnibus database, and the GEO2R tool was used to screen DEGs in HGIN and chronic gastritis tissue types. A DEG functional enrichment analysis was conducted using the Database for Annotation, Visualization, and Integrated Discovery. The STRING database was utilized to create a protein-protein interaction network, and the CytoHubba plug-in was used to screen the key genes of HGIN. Results: The incidence of LGIN increased with age, and most of the patients were aged between 45-59 years (P = 0.048). Lesions were found mainly in the cardia, mostly in people aged 60 (P < 0.05). Progression occurred in 42 of 449 patients, with a 9.4% rate of cancer development. Foci larger than 10 mm, ulcerative lesions, and an Helicobacter pylori-positive result were factors affecting the outcome of LGIN (P < 0.05). Seven core genes of HGIN were screened, including MYC, SOX2, CDX2, TBX3, KRT7, CDKN2A, and MUC5AC. Conclusion: The patients with LGIN reflected the potential for developing cancer. A magnifying gastroscope can contribute to the detection of early gastric cancer. Additionally, the MYC, CDX2, and TBX3 genes may act as specific biomarkers of HGIN.
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In this study, magnesium hydroxide (MH) flame-retarded starch/plant fiber composites containing various MH contents (0%, 5%, 15%, 15%) were prepared and named as TF-MH0, TF-MH5, TF-MH10, TF-MH15. Thermal degradation, flame retardancy, mechanical and microscopic characteristics were discussed. The reduction in the maximum thermal degradation rate revealed that the addition of MH provided improvement in the thermal stability of the composite. The horizontal burning test and the limiting oxygen index analysis suggested enhancement in flame retardancy with increasing MH content. Moreover, the density of composites initially decreased and then increased as the MH content increased. The tensile strength was positively correlated with the density, whereas the cushioning performance was negatively correlated with the density. Microscopic analysis showed that there was an interfacial interaction between MH and thermoplastic starch, which not only improves the thermal stability, but also promotes bubble nucleation as a nucleating agent. The cells of TF-MH10 were uniform and dense, thus TF-MH10 had the best buffering performance. Furthermore, the cell structure of TF-MH15 was short in diameter, small in number, and large in skeleton thickness; therefore, TF-MH15 had the highest tensile strength.
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Novel starch/fiber composites with open cell structures were proposed through thermo-cavity molding. To overcome the disadvantage of the water sensitivity of the resulting composites, poly-methyltriethoxysilane (PTS) was added as a waterproofing agent. The results showed that the addition of PTS improved the waterproof property of the composites. The composites with 15 g PTS (PTS-15) exhibited an optimal waterproof property. The water contact angle and drop absorption of the PTS-15 composites improved by 59.9% and 223.5%, respectively, compared with the values for those without PTS. Moreover, the addition of PTS could effectively prevent the degradation of the mechanical properties of the composites after water absorption. The rate of tensile property degradation for the PTS-15 composites reached 5.3%, whereas that for the PTS-0 composites totaled 56.6%. The chemical bonds and micro-structure of the composites were investigated to reveal the inherent mechanism of property changes. Fourier transform infrared spectra revealed the formation of new hydrogen bonds between starch and PTS. Hydrophobic groups, including Si-O-Si, Si-C, and Si-OH, were found in the resulting composites, thereby explaining the waterproof property changes. Scanning electron microscopy images showed that the open cell structure of the composites initially became denser and then loosened with the increase in the PTS content, resulting in the initial enhancement and the subsequent weakening of their mechanical properties.
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When chitosan/starch films were used as agricultural mulch films, the problem of rupture often occurred. In order to improve the elongation at break, chitosan/starch blend films were prepared by casting with different formulations (different ratios of chitosan to starch, different plasticizing components and different plasticizer ratios) in this research. The elongation at break of the film reached up to 104.1% when chitosan was plasticized with 10% glycerol and 0.94% ethylene glycol alone and then mixed according to a 1 : 0.6 chitosan-starch ratio. The fact that plasticizing starch, plasticizing chitosan or co-plasticizing starch and chitosan made a big difference to the mechanical properties of the films was discovered for the first time. The films with different plasticizing components were characterized by their mechanical properties, crystal structures and surface morphologies. Mechanical properties of the films were related to their crystallinity. The higher the crystallinity, the higher the elongation at break. Plasticizing starch alone facilitated the formation of hydrogen bonds and massive structures. Plasticizing chitosan alone was beneficial to the formation of network structures of the films and exhibited anti-plasticization at low plasticizer concentration.
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Starch-based composites with different modified starches were prepared by combining starches with sisal fibers to investigate the effects of single-modification/cross-modification of starch on the mechanical properties of new biodegradable composites. Mechanical test results showed that cross-modification of starch improved the toughness of the composites, whereas single-modification improved the tensile strength. The oxidized esterified starch-based composite (OESC) exhibited the best toughness, with improved elongation at break and Young's modulus by 136.1% and 54.3%, respectively, compared with a native starch-based composite. Meanwhile, the tensile strength of the esterified starch-based composite (ESC) improved by 61.6%. The hydrogen bonds, crystallinity, and micro-structure of the composites were investigated to reveal the inherent mechanism of the changes in performance. Fourier transform infrared spectroscopy showed that modification of starch changed the functional groups of starch. Thus, the ESC formed the strongest hydrogen bonds. X-ray diffraction analysis showed that the crystallinity decreased after the starches were modified. The OESC exhibited the lowest crystallinity, with a severely damaged structure. Many starch branches were combined with sisal fibers so that the composite was not easily pulled off. Scanning electron microscopy images showed that the OESC formed good cell structures internally when starch uniformly attached to the surface of the fibers.