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91.
Chitin and chitosan have been extensively investigated as a matrix of organic/inorganic composite. Barium, one of the radiopaque inorganic materials, can provide chitosan with radiopaque property by blending of chitosan and BaSO4. The filtered and deaerated chitosan/BaCl2 solutions were extruded into NaOH and Na2SO4 coagulation bath through a nozzle by gear pump. BaSO4 was synthesized by the reaction between BaCl2 and Na2SO4 in the coagulation bath, in which acidic chitosan solution was also solidified at the same time. In XRD, the introduction of BaSO4 into chitosan fibers reduced the inherent peak of chitosan fibers. In angiographic observation, chitosan/BaSO4 hybrid fibers exhibited the clear contrast images which become clear with an increase in BaSO4 content. 相似文献
92.
Yong-Chan Chung Jae Won Choi Young Jae Jung Samsook Han Byoung Chul Chun 《Fibers and Polymers》2013,14(12):2069-2076
Polyurethane (PU) copolymer is laterally linked with three kinds of metal ion indicator (calcein, calmagite, or eriochrome black T), with which free metal ion in aqueous solution is intended to be detected by PU color change. Metal ion detection by the indicator-PU fails due to the poor permeation of hydrophilic metal ion into hydrophobic PU layer. Instead, three surfactants with different ionic head groups, aerosol OT (AOT), cetyltrimethylammonium bromide (CTAB), and sodium dodecylsulfate (SDS), are tested for metal ion. Cationic CTAB exhibits an instant PU color change, but anionic AOT and SDS do not respond at all. Reason for the selective detection of cationic surfactant is the complex formation between cationic surfactant and indicator. Molecular interactions between PUs are affected by the laterally linked indicators based on the results by infrared spectra and differential thermal analysis. UV-vis spectra reveal that extra peak arising from the linked indicator appears compared to plain PU. The lateral linking of indicator to PU demonstrates, as well as the selective surfactant detection, a 454 % increase in tensile strength and reproducible shape recovery as high as 99 % compared to plain PU. 相似文献
93.
Woochul Chang Chang Youn Lee Jun-Hee Park Moon-Seo Park Lee-So Maeng Chee Soon Yoon Min Young Lee Ki-Chul Hwang Yong-An Chung 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):69-76
The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions. 相似文献
94.
Jae-Ku Oem Joon-Yee Chung Mee-Soon Kwon Toh-Kyung Kim Tae-Uk Lee You-Chan Bae 《Journal of veterinary science (Suw?n-si, Korea)》2013,14(1):91-94
Culicoides biting midges were collected on three cattle farms weekly using light traps overnight from May to October between 2010 and 2011 in the southern part of Korea. The seasonal and geographical abundance of Culicodes spp. were measured. A total of 16,538 biting midges were collected from 2010 to 2011, including seven species of Culicoides, four of which represented 98.42% of the collected specimens. These four species were Culicodes (C.) punctatus (n = 14,413), C. arakawae (n = 1,120), C. oxystoma (n = 427), and C. maculatus (n = 318). C. punctatus was the predominant species (87.15%). 相似文献
95.
Unsuccessful Cyclosporine plus Prednisolone Therapy for Autoimmune
Meningoencephalitis in Three Dogs
96.
Chung Sarit Takeuchi Junichiro Fujihara Masayuki Oeurng Chantha 《Paddy and Water Environment》2019,17(2):255-263
Paddy and Water Environment - In Cambodia, rice production is important for the majority of rural populations as the main source of income. However, historical extreme flood events, especially the... 相似文献
97.
Chung SH Kim IH Park HG Kang HS Yoon CS Jeong HY Choi NJ Kwon EG Kim YJ 《Journal of agricultural and food chemistry》2008,56(9):3311-3316
This study was performed to discover bifidobacteria isolated from human intestines that optimally convert linoleic acid (LA) to conjugated linoleic acid (CLA) and to optimize the culture conditions of milk fermentation. One hundred and fifty neonatal bifidobacteria were screened for CLA-producing ability, and Bifidobacterium breve LMC 017 was selected as it showed about 90% conversion of free LA in MRS broth. The selected strain showed resistance at 0.5% LA in microaerophillic conditions. When monolinolein (LA 90%) was used as a substrate for CLA production, the conversion rate was lower compared to free LA, but the growth rate was unaffected during the milk fermentation. There was no significant difference in CLA production between aerobic and anaerobic conditions, and little decline in CLA was shown after the maximal CLA level had been reached. CLA production increased by 80% with 24 h of incubation in milk containing additional skim milk (5%), where the proteins may have facilitated the production of CLA by enhancing the interaction of substrate with the bacteria. CLA production did not decline after 9 h of fermentation and an additional 12 weeks of storage with other commercial starters. This demonstrates the possibility of using this strain as a costarter in the production of CLA-enriched yogurt. 相似文献
98.
Choi NJ Park HG Kim YJ Kim IH Kang HS Yoon CS Yoon HG Park SI Lee JW Chung SH 《Journal of agricultural and food chemistry》2008,56(22):10908-10912
This study was designed to isolate bifidobacteria from human intestines that efficiently converts monolinolein, a monoglyceride form of linoleic acid, into conjugated linoleic acid (CLA), as well as to optimize culture conditions for improving CLA production during milk fermentation. Among 150 screened neonatal bifidobacteria, Bifidobacterium breve LMC 520 showed the highest CLA-producing ability and was tested with different types of fat substrates at various concentrations to determine the optimal conditions for CLA production. Monolinolein was tested as a substrate for CLA production. The incubation time optimized for CLA production was 24 h, and CLA production was proportionally increased with monolinolein concentration. The incubation of LMC 520 with commercial starter strains caused minimal reduction in CLA production. Our results demonstrate that the CLA-producing ability of B. breve LMC 520 could offer beneficial effects when utilized as a starter culture for the development of functional dairy products. 相似文献
99.
Protective effect of anthocyanins from black soybean seed coats on UVB-induced apoptotic cell death in vitro and in vivo 总被引:1,自引:0,他引:1
Tsoyi K Park HB Kim YM Chung JI Shin SC Shim HJ Lee WS Seo HG Lee JH Chang KC Kim HJ 《Journal of agricultural and food chemistry》2008,56(22):10600-10605
UVB radiation proves to be one of the most relevant environmental risks because of its hazardous effects, such as premature skin aging and especially skin photocarcinogenesis. Anthocyanins, water-soluble pigments present in plants, are known to be powerful antioxidants that help protect plants from UV damage. In this study, we aimed at investigating the protective effect of anthocyanins from black soybean [Glycine max (L.) Merr] seed coats on UVB-induced apoptosis, and furthermore, we investigated the molecular mechanism responsible for regulation of apoptosis in vitro and in vivo. Pretreatment with anthocyanins reduced UVB-induced reactive oxygen species levels and inhibited UVB-induced apoptotic cell death through the prevention of caspase-3 pathway activation and reduction of proapoptotic Bax protein levels. UVB irradiation induced apoptotic cell death, which was inhibited by topical application of anthocyanins in hairless mice. It is concluded that anthocyanins from the seed coat of black soybeans may be useful compounds to modulate UVB-induced photoaging. 相似文献
100.
Jong-Soon Choi Seong-Woo Cho Tae-Seon Kim Kun Cho Seok-Soon Han Hong-Ki Kim Sun-Hee Woo Keun-Yook Chung 《Soil biology & biochemistry》2008,40(6):1370-1378
The natural soil mineral conditioner illite effectively improved the germination and growth of lettuce when applied in particulate or powdered form. When illite was given in particulate and powdered forms, the germination rate of lettuce seeds improved remarkably up to 93% and 133%, respectively. Contrary to the developmental effects, the growth rate of lettuce treated with particulate illite improved slightly by 23%; powdered illite had no significant effects on lettuce growth rate. Thus, illite primarily affects seed germination rather than the growth of lettuce. To examine illite-induced proteins related to lettuce growth, differentially expressed proteins in lettuce leaves were analyzed by two-dimensional gel electrophoresis (2-DE) and matrix-assisted laser desorption ionization-time of flight/time of flight mass spectrometry (MALDI-TOF/TOF MS) followed by Mascot search. From the proteomic analysis, five down-regulated proteins were identified related to storage protein, carbon metabolism and energy conversion. Three up-regulated proteins were related to energy production/conversion and carbon fixation. These results demonstrate that illite treatment as a soil conditioner helps lettuce seed germination and lettuce growth by regulating carbon metabolic flux. 相似文献