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981.
Arachchige Maheshika Kumari Jayasinghe Kirinde Gedara Isuru Sandanuwan Kirindage Ilekuttige Priyan Shanura Fernando Eui Jeong Han Gun-Woo Oh Won-Kyo Jung Ginnae Ahn 《Marine drugs》2022,20(2)
Recent studies have revealed that marine brown seaweeds contain numerous bioactive compounds which exhibit various bioactivities. The present study investigated the effect of low molecular weight fucoidan (SCF) isolated from Sargassum confusum, a brown alga, on inflammatory responses and oxidative stress in HaCaT keratinocytes stimulated by tumor necrosis factor (TNF)-α/interferon (IFN)-γ. SCF significantly increased the cell viability while decreasing the intracellular reactive oxygen species (ROS) production in TNF-α/IFN-γ-stimulated HaCaT keratinocytes. In addition, SCF effectively reduced inflammatory cytokines (interleukin (IL)-1β, IL-6, IL-8, IL-13, TNF-α, and IFN-γ) and chemokines (Eotaxin, macrophage-derived chemokine (MDC), regulated on activation, normal T cell expressed and secreted (RANTES), and thymus and activation-regulated chemokine (TARC)) expression, by down-regulating the expression of epithelial and epidermal innate cytokines (IL-25, IL-33, and thymic stromal lymphopoietin (TSLP)). Furthermore, SCF suppressed the activation of TNF-α/IFN-γ-stimulated mitogen-activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) signaling pathways, while activating the nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway. The cytoprotective effect of SCF against TNF-α/IFN-γ stimulation was considerably reduced upon inhibition of HO-1 activity by ZnPP. Overall, these results suggest that SCF effectively suppressed inflammatory responses and oxidative stress in TNF-α/IFN-γ-stimulated HaCaT keratinocytes via activating the Nrf2/HO-1 signaling pathway. 相似文献
982.
Authors studied on the applicability of image analysis technique using a scanner with a CCD (charged coupled deviced) to the
evaluation of evenness of nonwovens because it has distinctive features to considerably save time and labor in the analysis
compared with other classical methods. As specimens for the experiment, two different types that are unpatterned and patterned
ones were prepared. For the unpatterned specimen, webs were chermically bonded, while for the patterned specimen, webs being
thermally calendered with engraved roller. Several webs having various areal densities were prepared and bonded. Coefficient
of variation (CV%) was used as a parameter to evaluate the evenness. Scanning conditions could be suitably set up through
comparing the total variance to the between-group variance and to the within-group variance, respectively, on the images scanned
at the different conditions. The 2D convolution method with smoothing filter kernel was introduced to further filter the noises
on the scanned images. After the filtering process, the increase of web areal densities gave an uniform decrease of the CV%.
This showed that the scanned image analysis with proper filtering process could be successfully applicable to the evaluation
of evenness in nonwovens. 相似文献
983.
Seung Ho Jeong Kwan Han Yoon Byung Gil Min Young Sil Lee Sang Pal Lee Sang Bong Park 《Fibers and Polymers》2017,18(9):1638-1643
Poly(ethylene terephthalate) (PET) copolymers containing fluorenylidene bis(2-phenoxyethanol) (FBPE) were prepared. The glass transition temperature of copolymers increased continuously with the composition of FBPE. The glass transition temperature of PET/FBPE copolymer at loading of 15 mol% FBPE was 107 °C, which was 35 °C higher than that of PET. The melting temperature of PET/FBPE copolymers was decreased with the composition of FBPE, and it disappeared above 6 mol% of FBPE. The heat deflection temperature of copolymers increased from 60.7 °C for PET to 89.9 °C for the copolymer containing 15 mol% of FBPE. The values of optical transmittance of copolymers were 89-90 % at 550 nm, and no significant change was observed with the FBPE composition. The impact strength value of copolymer at loading of 10 mol% FBPE was 26 J/m, which was 20 J/m higher than that of PET. 相似文献
984.
Shi-Ying Huang Nan-Fu Chen Wu-Fu Chen Han-Chun Hung Hsin-Pai Lee Yen-You Lin Hui-Min Wang Ping-Jyun Sung Jyh-Horng Sheu Zhi-Hong Wen 《Marine drugs》2012,10(9):1899-1919
Three decades ago, the marine-derived compound sinularin was shown to have anti-edematous effects on paw edema induced by carrageenan or adjuvant. To the best of our knowledge, no new studies were conducted to explore the bioactivity of sinularin until we reported the analgesic properties of sinularin based on in vivo experiments. In the present study, we found that sinularin significantly inhibits the upregulation of proinflammatory proteins, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) and upregulates the production of transforming growth factor-β (TGF-β) in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells according to western blot analysis. We found that subcutaneous (s.c.) administration of sinularin (80 mg/kg) 1 h before carrageenan injection significantly inhibited carrageenan-induced nociceptive behaviors, including thermal hyperalgesia, mechanical allodynia, cold allodynia, and hindpaw weight-bearing deficits. Further, s.c. sinularin (80 mg/kg) significantly inhibited carrageenan-induced microglial and astrocyte activation as well as upregulation of iNOS in the dorsal horn of the lumbar spinal cord. Moreover, s.c. sinularin (80 mg/kg) inhibited carrageenan-induced tissue inflammatory responses, redness and edema of the paw, and leukocyte infiltration. The results of immunohistochemical studies indicate that s.c. sinularin (80 mg/kg) could upregulate production of TGF-β1 in carrageenan-induced inflamed paw tissue. The present results demonstrate that systemic sinularin exerts analgesic effects at the behavioral and spinal levels, which are associated with both inhibition of leukocyte infiltration and upregulation of TGF-β1. 相似文献
985.
Hsu-Ming Chung Li-Chung Hu Wei-Hsuan Yen Jui-Hsin Su Mei-Chin Lu Tsong-Long Hwang Wei-Hsien Wang Ping-Jyun Sung 《Marine drugs》2012,10(10):2246-2253
A new halimane-type diterpenoid, echinohalimane A (1), was isolated from a gorgonian, identified as Echinomuricea sp. The structure of 1 was determined by spectroscopic methods and this compound was found to exhibit cytotoxicity toward various tumor cells and display an inhibitory effect on the release of elastase by human neutrophils. Echinohalimane A (1) is the first halimane analogue from the marine organisms belonging to phylum Cnidaria. 相似文献
986.
Hyo Young Jung Woosuk Kim Hyun Jung Kwon Dae Young Yoo Sung Min Nam Kyu Ri Hahn Sun Shin Yi Jung Hoon Choi Dae Won Kim Yeo Sung Yoon In Koo Hwang 《Marine drugs》2020,18(12)
Laminaria japonica is widely cultivated in East Asia, including South Korea. Fucoidan, a main component of L. japonica, protects neurons from neurological disorders such as ischemia and traumatic brain injury. In the present study, we examined the effects of extract from fermented L. japonica on the reduction of proliferating cells and neuroblasts in mice that were physically (with electric food shock) or psychologically (with visual, auditory and olfactory sensation) stressed with the help of a communication box. Vehicle (distilled water) or fermented L. japonica extract (50 mg/kg) were orally administered to the mice once a day for 21 days. On the 19th day of the treatment, physical and psychological stress was induced by foot shock using a communication box and thereafter for three days. Plasma corticosterone levels were significantly increased after exposure to physical stress and decreased Ki67 positive proliferating cells and doublecortin immunoreactive neuroblasts. In addition, western blot analysis demonstrated that physical stress as well as psychological stress decreased the expression levels of brain-derived neurotrophic factor (BDNF) and the number of phosphorylated cAMP response element binding protein (pCREB) positive nuclei in the dentate gyrus. Fermentation of L. japonica extract significantly increased the contents of reduced sugar and phenolic compounds. Supplementation with fermented L. japonica extract significantly ameliorated the increases of plasma corticosterone revels and decline in the proliferating cells, neuroblasts, and expression of BDNF and pCREB in the physically stressed mice. These results indicate that fermented L. japonica extract has positive effects in ameliorating the physical stress induced reduction in neurogenesis by modulating BDNF and pCREB expression in the dentate gyrus. 相似文献
987.
Photoresponsive side chain copolymer and homopolymer containing an aminonitroazobenzene were synthesized for studying photoisomerization
behavior and photo-induced anisotropy.Trans-to-cis photoisomerization was observed under the exposure of a circularly polarized visible light with UV-Vis absorption spectroscopy.
Reorientation of polar azobenzene molecules induced optical anisotropy under a linearly polarized light at 532 nm. Polarized
absorption spectroscopy was employed to investigate the anisotropy of the polymer film during irradiation of the excitation
light. Layers of two photosensitive polymers were used for aligning liquid crystal (LC) molecules instead of one of the rubbed
polyimide layers in the conventional twisted nematic cell. For producing homogeneous alignment of a nematic LC molecule, a
linearly polarized light was exposed to the films of two polymers. The stability of the LC alignment upon the linearly polarized
light exposure was also studied. 相似文献
988.
The HVI properties and Mantis® single fiber tensile properties were analyzed to evaluate the relationship between fiber and bundle tensile properties. For this study, a new method has been developed for estimating the modulus and toughness of cotton fiber bundles directly from the HVI tenacity-elongation curves. The single fiber tensile properties were shown to be translated well into the bundle tensile properties. The single fiber breaking elongation was found to be the most significant contributing factor to bundle tensile properties. The bundle breaking elongation and toughness were shown to increase as the single fiber breaking elongation increased. The bundle modulus increased as the single fiber breaking elongation and/or standard deviation of single fiber breaking elongation decreased. 相似文献
989.
Poly(hydroxamic acid) resin beads were prepared and complexed with various metal ions. We used IR spectroscopy to investigate
the structure of metal complex. It proved that the products formed by introduction of metal ions gave stable and colored complex.
It was found that the resin bead as synthesized would be a good column packing material for continuous extraction. Energy
dispersive spectroscopy was used to study the distribution of metal ions in the resin matrix. It could be tentatively concluded
that adsorption and diffusion of metal ions in the chelating resins mainly depended on the loading of the resin matrix which
indicated interacting sites with metal ions. 相似文献
990.
Jyh-Horng Sheu Yung-Husan Chen Yu-Hsin Chen Yin-Di Su Yu-Chia Chang Jui-Hsin Su Ching-Feng Weng Chia-Hung Lee Lee-Shing Fang Wei-Hsien Wang Zhi-Hong Wen Yang-Chang Wu Ping-Jyun Sung 《Marine drugs》2014,12(4):2164-2181
The structures, names, bioactivities and references of 138 briarane-type diterpenoids, including 87 new compounds, are summarized in this review. All the briarane-type compounds mentioned in this review article were obtained from gorgonian corals including the genus Briareum, Dichotella, Junceella and Verrucella. Some of these compounds showed potential bioactivities. 相似文献