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101.
Hyun Ook Seo Myung‐Geun Jeong Kwang‐Dae Kim Dae Han Kim Young Dok Kim Dong Chan Lim 《Surface and interface analysis : SIA》2014,46(8):544-549
Degradation behaviors of poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) layers on NiO in the presence of H2O at ambient pressure and dark conditions were studied using X‐ray photoelectron spectroscopy (XPS). Upon H2O exposure at 120 °C, partial oxidation of P3HT together with molecular water incorporation, but with the maintained local ring‐structure, were deduced by XPS. Valence band spectra of XPS evidenced that the partial oxidation of P3HT local structure could alter π‐conjugation systems of P3HT layers, forming additional electronic states close to its original highest occupied molecular orbital. For comparison, P3HT surface was also exposed to O2, and no change in the S 2p and C 1s spectra was found by O2 exposure at 120 °C, implying that H2O plays a major role at the initial stage of P3HT oxidation. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
102.
Electrophoresis 2014, 35, 1504–1508. DOI: 10.1002/elps.201400001 Combination of DNA biobarcode assay with micro‐capillary electrophoretic analysis on a chip allows us to perform breast and colorectal cancer cell detection with high sensitivity, multiplexity, and accuracy.
103.
Chemical interaction between Paeonia lactiflora and Glycyrrhiza uralensis,the components of Jakyakgamcho‐tang,using a validated high‐performance liquid chromatography method: Herbal combination and chemical interaction in a decoction 下载免费PDF全文
The herbal combination is the basic unit of a herbal formula that affects the chemical characteristics of individual herbs. In the present study, a method of simultaneous determination of the 11 marker compounds in Jakyakgamcho‐tang was developed using high‐performance liquid chromatography with photodiode array detection. The validated analytical method was successfully applied to approach the chemical interaction between Paeonia lactiflora and Glycyrrhiza uralensis in co‐decoction. In P. lactiflora, the contents of gallic acid, oxypaeoniflorin, (+)‐catechin, paeoniflorin, and benzoylpaeoniflorin were decreased, while those of albiflorin and benzoic acid were increased; in G. uralensis, the contents of liquiritin, isoliquiritin, ononin, and glycyrrhizin were decreased, when decocting two herbs together. Moreover, as the ratio between P. lactiflora and G. uralensis was increased, the contents of chemical contents from each herb were proportionally increased. However, each content of marker compound per the gram of herbal medicine was decreased as the ratio of combinative herbs increased. The results showed that P. lactiflora and G. uralensis affect the extraction efficiency of chemical compounds in a Jakyakgamcho‐tang decoction. Overall, the method established in this study was simple, rapid, and accurate, and would be useful for the determination of marker compounds and for the investigation of the chemical interaction between herbal medicines. 相似文献
104.
Eun Hee-Chul Yang Hee-Chul Kim Hyung-Ju Kim Sung-Jun Jeon Min-Ku Lee Keun-Young Seo Bum-Kyoung 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3735-3744
Journal of Radioanalytical and Nuclear Chemistry - CaCO3 powder containing C-14, which has a long half-life, is generated from the treatment process of spent activated carbons from the air cleaning... 相似文献
105.
Eui-Baek Byun Ha-Yeon Song Woo Sik Kim Jeong Moo Han Ho Seong Seo Woo Yong Park Kwangwook Kim Eui-Hong Byun 《Molecules (Basel, Switzerland)》2021,26(6)
Although our previous study revealed that gamma-irradiated chrysin enhanced anti-inflammatory activity compared to intact chrysin, it remains unclear whether the chrysin derivative, CM1, produced by gamma irradiation, negatively regulates toll-like receptor (TLR) signaling. In this study, we investigated the molecular basis for the downregulation of TLR4 signal transduction by CM1 in macrophages. We initially determined the appropriate concentration of CM1 and found no cellular toxicity below 2 μg/mL. Upon stimulation with lipopolysaccharide (LPS), CM1 modulated LPS-stimulated inflammatory action by suppressing the release of proinflammatory mediators (cytokines TNF-α and IL-6) and nitric oxide (NO) and downregulated the mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways. Furthermore, CM1 markedly elevated the expression of the TLR negative regulator toll-interacting protein (Tollip) in dose- and time-dependent manners. LPS-induced expression of cell surface molecules (CD80, CD86, and MHC class I/II), proinflammatory cytokines (TNF-α and IL-6), COX-2, and iNOS-mediated NO were inhibited by CM1; these effects were prevented by the knockdown of Tollip expression. Additionally, CM1 did not affect the downregulation of LPS-induced expression of MAPKs and NF-κB signaling in Tollip-downregulated cells. These findings provide insight into effective therapeutic intervention of inflammatory disease by increasing the understanding of the negative regulation of TLR signaling induced by CM1. 相似文献
106.
107.
Ki Cheol Hwang Hyun Young Shin Woo Jung Kim Mi Suk Seo Hoon Kim 《Molecules (Basel, Switzerland)》2021,26(6)
Persimmon (Diospyros kaki), a familiar and widespread fruit worldwide, is known to exhibit several physiological effects because of the presence of pharmacologically active compounds called phytochemicals. However, its high-molecular-weight compounds, particularly polysaccharides, have not been extensively studied. In this study, D. kaki extract (DK) was fractionated into low- and high-molecular-weight fractions (DK-L and DK-H, respectively) through ethanol fractionation, and their effects on antioxidant, anti-inflammatory, and antiwrinkle activities were investigated by an in vitro system. DK-H contained significantly higher contents of neutral sugar, uronic acid, and polyphenols compared to DK and DK-L. Furthermore, DK-H exhibited significantly improved pharmacological activities, such as antioxidant, anti-inflammatory, and antiwrinkle properties, compared to those of DK and DK-L, demonstrating that DK-H may play an important role in mediating the beneficial effects of persimmon. Sugar composition analysis and molecular characterization indicated that DK-H consisted of a galacturonic acid (GalA)-rich polysaccharide with a molecular weight of >345 kDa that mainly comprised GalA and small amounts of neutral sugar and polyphenol residues. These results suggest that the bioactive fraction DK-H is likely to be a GalA-rich pectic polysaccharide containing a small number of polyphenol residues, which may be a novel candidate in the pharmaceutical and cosmeceutical industries. 相似文献
108.
Tvaskis V Christy ME Arrington J Asaturyan R Baker OK Blok HP Bosted P Boswell M Bruell A Cochran A Cole L Crowder J Dunne J Ent R Fenker HC Filippone BW Garrow K Gasparian A Gomez J Jackson HE Keppel CE Kinney E Lapikás L Liang Y Lorenzon W Lung A Mack DJ Martin JW McIlhany K Meekins D Milner RG Mitchell JH Mkrtchyan H Moreland B Nazaryan V Niculescu I Opper A Piercey RB Potterveld DH Rose B Sato Y Seo W Smith G Spurlock K van der Steenhoven G Stepanyan S Tadevosian V Uzzle A Vulcan WF Wood SA 《Physical review letters》2007,98(14):142301
We report on a study of the longitudinal to transverse cross section ratio, R=sigmaL/sigmaT, at low values of x and Q2, as determined from inclusive inelastic electron-hydrogen and electron-deuterium scattering data from Jefferson Laboratory Hall C spanning the four-momentum transfer range 0.06相似文献
109.
Ultrastructural aspects of intrahyphal hyphae formation were investigated in Elsinoe fawcettii by transmission electron microscopy. Desiccated and hydrated cultures of E. fawcettii hyphae in liquid and solid media were prepared to determine the effects of water/nutrient availability and media fluidity on the formation of intrahyphal hyphae of the fungus. In all the culture conditions, intrahyphal hyphae were observed in enclosing hyphae. Electron-transparent hyphal cell walls clearly delimited intrahyphal hyphae from the cytoplasm of enclosing hyphae. Intrahyphal hyphae occupied most of the lumen of the enclosing hyphae, and showed intact hyphal cytoplasm with distinct organelles and inclusions. Intrahyphal hyphae were found to grow out of the degenerated hyphae that were almost devoid of cellular contents (simple intrahyphal hyphae). Some intrahyphal hyphae appeared to push aside a septum and passed into the adjacent hyphal cell. Besides a single intrahyphal hypha, instances were noted where enclosing hyphae contained several individual intrahyphal hyphae (multiple intrahyphal hyphae). Other enclosing hyphae contained intrahyphal hyphae, which also had intrahyphal hyphae (compound intrahyphal hyphae). The cell wall of intrahyphal hyphae showed the continuity with the cell wall of the enclosing hyphae. Concentric bodies typical of ascomycetes occurring in dry habitats were not found in all the types of hyphae. These results suggest that intrahyphal hyphae formation of E. fawcettii does not require plant defense responses. The fungus is thought to form intrahyphal hyphae during the saprophytic phase in ex planta ecological niches as well as the parasitic phase in host parts. 相似文献
110.
Farhan M. Khan Muhammad A. Abbasi Aziz-ur-Rehman Sabahat Z. Siddiqui Abdul R. Sadiq Butt Hussain Raza Ayesha Zafar Syed A. Ali Shah Muhammad Shahid Sung-Yum Seo 《Journal of heterocyclic chemistry》2021,58(5):1089-1103
By using a convergent methodology, a novel series of N-arylated 4-yl-benzamides containing a bi-heterocyclic thiazole–triazole core was synthesized, and the structures of these hybrid molecules, 9a–k , were corroborated through spectral analyses. The in vitro studies of these multifunctional molecules demonstrated their potent carbonic anhydrase inhibition relative to the standard used. The kinetics mechanism was exposed by Lineweaver–Burk plots, which revealed that 9j inhibited carbonic anhydrase non-competitively by forming an enzyme-inhibitor complex. The inhibition constants Ki calculated from Dixon plots for this compound was 1.2 μM. The computational study was also persuasive with the experimental results, and these molecules disclosed good results of all scoring functions and interactions, which suggested a good binding to carbonic anhydrase. So, it was predicted from the inferred results that these molecules might be considered as promising medicinal scaffolds for various diseases related to the uncontrolled production of this enzyme. 相似文献