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831.
Chia-Ming Chang Chi-Mu Chuang Mong-Lien Wang Yi-Ping Yang Jen-Hua Chuang Ming-Jie Yang Ming-Shyen Yen Shih-Hwa Chiou Cheng-Chang Chang 《International journal of molecular sciences》2016,17(8)
Clear cell (CCC), endometrioid (EC), mucinous (MC) and high-grade serous carcinoma (SC) are the four most common subtypes of epithelial ovarian carcinoma (EOC). The widely accepted dualistic model of ovarian carcinogenesis divided EOCs into type I and II categories based on the molecular features. However, this hypothesis has not been experimentally demonstrated. We carried out a gene set-based analysis by integrating the microarray gene expression profiles downloaded from the publicly available databases. These quantified biological functions of EOCs were defined by 1454 Gene Ontology (GO) term and 674 Reactome pathway gene sets. The pathogenesis of the four EOC subtypes was investigated by hierarchical clustering and exploratory factor analysis. The patterns of functional regulation among the four subtypes containing 1316 cases could be accurately classified by machine learning. The results revealed that the ERBB and PI3K-related pathways played important roles in the carcinogenesis of CCC, EC and MC; while deregulation of cell cycle was more predominant in SC. The study revealed that two different functional regulation patterns exist among the four EOC subtypes, which were compatible with the type I and II classifications proposed by the dualistic model of ovarian carcinogenesis. 相似文献
832.
Chih‐Chun Teng Chen‐Chi M. Ma Shin‐Yi Yang Kuo‐Chan Chiou Tzong‐Ming Lee Chin‐Lung Chiang 《应用聚合物科学杂志》2012,123(2):888-896
The well dispersed multiwalled carbon nanotube (MWCNT)/epoxy composites were prepared by functionalization of the MWCNT surfaces with glycidyl methacrylate (GMA). The morphology and thermal properties of the epoxy nanocomposites were investigated and compared with the surface characteristics of MWCNTs. GMA‐grafted MWCNTs improved the dispersion and interfacial adhesion in epoxy resin, and enhanced the network structure. The storage modulus of 3 phr GMA‐MWCNTs/epoxy composites at 50°C increased from 0.32 GPa to 2.87 GPa (enhanced by 799%) and the increased tanδ from 50.5°C to 61.7°C (increased by 11.2°C) comparing with neat epoxy resin, respectively. Furthermore, the thermal conductivity of 3 phr GMA‐MWCNTs/epoxy composite is increased by 183%, from 0.2042 W/mK (neat epoxy) to 0.5781 W/mK. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
833.
The mixed monolayer behavior of stereoregular poly(methyl methacrylate) (PMMA) and poly(vinyl cinnamate) (PVCN) was investigated from the measurements of surface pressure–area per molecule (π–A) isotherms at three different temperatures of 25 ± 1, 32.5 ± 1, and 40 ± 1°C. The miscibility and nonideality of the mixed monolayers were examined by calculating the excess area as a function of composition. Positive and negative deviations from ideality were observed. Negative deviations were observed mostly in syndiotactic PMMA (sPMMA) and PVCN blends suggesting the existence of favorable interactions. However, positive deviations in most isotactic PMMA (iPMMA) and PVCN blends indicated that the existence of unfavorable interactions. Atactic PMMA and PVCN blends demonstrated intermediate deviation behavior to sPMMA and iPMMA blends. On the basis of the results of π–A isotherms, the monolayer miscibility between PMMA and PVCN was in the majority not in agreement with the studies on the same blends in the bulk state. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
834.
Jau‐Wern Chiou Wei‐Hao Huang Shih‐Jye Sun Chang‐Feng Yu Hsiung Chou Hung‐Duen Yang Yueh‐Chung Yu Ting‐Shan Chan Hong‐Ji Lin Krishna Kumar Wanli Yang Jinghua Guo 《Journal of the American Ceramic Society》2014,97(2):657-661
This study examines Al‐doped ZnO (AZO) transparent conductive thin films prepared on glass substrate using the pulsed laser deposition method with an expanding magnetic field perpendicular to the sample surface. O K‐, Zn L3‐, and Al K‐edge X‐ray absorption near‐edge structure (XANES) and X‐ray emission spectroscopy (XES) were used to investigate the relationship between the effects of magnetic field size and the electronic structure of AZO thin films. Analysis of the XANES spectra showed increasing O 2p states as film resistance decreases, suggesting that the enrichment of the O 2p‐dangling bond along the c‐axis is the main factor affecting the electric performance of AZO thin films. Magnetic field size affects electrons itinerating from Zn atoms to Al sites through O 2p–Zn 3d and O 2p–Al 3sp hybridization and consequently weakens O 2p–Zn 3d hybridization with the downsizing of the crystallite size. XES and XANES spectra of O 2p states at the O K‐edge exhibit that the conduction‐band minimum affects Eg and the valence‐band maximum is nearly unaffected by changes in magnetic field size. Factors affecting the resistance/electric conductivity of AZO thin films are the preferential orientation of (002) along the c‐axis, the thermal/annealing effect accompanied by the changes of magnetic field size, the surface effect, energy bandgap, and the density of unoccupied O 2p‐derived states. 相似文献
835.
Shu-Yuan Chiou Choi-Lan Ha Pei-Shan Wu Chiu-Ling Yeh Ying-Shan Su Man-Po Li Ming-Jiuan Wu 《International journal of molecular sciences》2015,16(12):29522-29541
Camellia tenuifloria is an indigenous Camellia species used for the production of camellia oil in Taiwan. This study investigated for the first time the potential antioxidant, anti-tyrosinase and anti-inflammatory activities of oil production byproducts, specifically those of the fruit shell, seed shell, and seed pomace from C. tenuifloria. It was found that the crude ethanol extract of the seed shell had the strongest DPPH scavenging and mushroom tyrosinase inhibitory activities, followed by the fruit shell, while seed pomace was the weakest. The IC50 values of crude extracts and fractions on monophenolase were smaller than diphenolase. The phenolic-rich methanol fraction of seed shell (SM) reduced nitric oxide (NO) production, and inducible nitric oxide synthase (iNOS) expression in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells. It also repressed the expression of IL-1β, and secretion of prostaglandin E2 (PGE2) and IL-6 in response to LPS. SM strongly stimulated heme oxygenase 1 (HO-1) expression and addition of zinc protoporphyrin (ZnPP), a HO-1 competitive inhibitor, reversed the inhibition of NO production, indicating the involvement of HO-1 in its anti-inflammatory activity. The effects observed in this study provide evidence for the reuse of residues from C. tenuifloria in the food additive, medicine and cosmetic industries. 相似文献
836.
Ching-Feng Wu Ching-Yang Wu Robin Y.-Y. Chiou Wei-Cheng Yang Chuen-Fu Lin Chao-Min Wang Po-Hsun Hou Tzu-Chun Lin Chan-Yen Kuo Geng-Ruei Chang 《International journal of molecular sciences》2021,22(9)
Zotarolimus is a semi-synthetic derivative of rapamycin and a novel immunosuppressive agent used to prevent graft rejection. The pharmacological pathway of zotarolimus restricts the kinase activity of the mammalian target of rapamycin (mTOR), which potentially leads to reductions in cell division, cell growth, cell proliferation, and inflammation. These pathways have a critical influence on tumorigenesis. This study aims to examine the anti-tumor effect of zotarolimus or zotarolimus combined with 5-fluorouracil (5-FU) on A549 human lung adenocarcinoma cell line implanted in BALB/c nude mice by estimating tumor growth, apoptosis expression, inflammation, and metastasis. We established A549 xenografts in nude mice, following which we randomly divided the mice into four groups: control, 5-FU (100 mg/kg/week), zotarolimus (2 mg/kg/day), and zotarolimus combined with 5-FU. Compared the results with those for control mice, we found that mice treated with zotarolimus or zotarolimus combined with 5-FU retarded tumor growth; increased tumor apoptosis through the enhanced expression of cleaved caspase 3 and extracellular signal-regulated kinase (ERK) phosphorylation; decreased inflammation cytokines levels (e.g., IL-1β, TNF-α, and IL-6); reduced inflammation-related factors such as cyclooxygenase-2 (COX-2) protein and nuclear factor-κB (NF-κB) mRNA; enhanced anti-inflammation-related factors including IL-10 and inhibitor of NF-κB kinase α (IκBα) mRNA; and inhibited metastasis-related factors such as transforming growth factor β (TGF-β), CD44, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF). Notably, mice treated with zotarolimus combined with 5-FU had significantly retarded tumor growth, reduced tumor size, and increased tumor inhibition compared with the groups of mice treated with 5-FU or zotarolimus alone. The in vivo study confirmed that zotarolimus or zotarolimus combined with 5-FU could retard lung adenocarcinoma growth and inhibit tumorigenesis. Zotarolimus and 5-FU were found to have an obvious synergistic tumor-inhibiting effect on lung adenocarcinoma. Therefore, both zotarolimus alone and zotarolimus combined with 5-FU may be potential anti-tumor agents for treatment of human lung adenocarcinoma. 相似文献
837.
The use of ArF laser radiation at wavelength 193 nm to generate ozone from various pressures of oxygen gases was investigated. Kinetic results were interpreted from molecular spectroscopy and dynamics points of view. The 193 nm radiation can dissociate both oxygen molecules and ozone to produce oxygen atoms. This is an essential process in ozone generation. In this investigation, we focused on the mechanisms that ozone dissociates into three oxygen atoms or vibrationally excited oxygen molecules. The above mechanisms imply a potential process to improve the efficiency of ozone generation. 相似文献
838.
Synthetic routes to primary and N-alkyl α-keto amides are presented in this paper. Primary α-keto amides may be prepared by using an aldehyde as starting material.
Commercially available α-keto acids may be coupled in high yield with primary amines by the mixed carbonic anhydride method
affording N-alkyl α-keto amides. Alternatively, N-alkyl α-keto amides may be prepared by coupling long-chain α-hydroxy acids with amino components, followed by oxidation with
pyridinium dichromate or NaOCl in the presence of 4-acetamido-2,2,6,6-tetramethyl-1-piperidinyloxy free radical. The α-keto
amide derivatives prepared according to these procedures were tested for their ability to form stable monomolecular films
at the air/water interface. The inhibition of porcine pancreatic lipase by the α-keto amides, spread as mixed films with 1,2-dicaprin,
was studied with the monolayet technique. Among the compounds tested in this study, methyl 2-[(2-ketododecanoyl)aminol]hexadecanoate
was shown to be the most potent inhibitor, causing a 50% decrease in lipase activity at a 0.09 molar fraction. 相似文献