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371.
You-Jung Ha Yong Seok Choi Ye Rim Oh Eun Ha Kang Gilson Khang Yong-Beom Park Yun Jong Lee 《Marine drugs》2021,19(3)
Fucoxanthin (FX), a natural carotenoid present in edible brown seaweed, is known for its therapeutic potential in various diseases, including bone disease. However, its underlying regulatory mechanisms in osteoclastogenesis remain unclear. In this study, we investigated the effect of FX on osteoclast differentiation and its regulatory signaling pathway. In vitro studies were performed using osteoclast-like RAW264.7 cells stimulated with the soluble receptor activator of nuclear factor-κB ligand or tumor necrosis factor-alpha/interleukin-6. FX treatment significantly inhibited osteoclast differentiation and bone resorption ability, and downregulated the expression of osteoclast-specific markers such as nuclear factor of activated T cells 1, dendritic cell-specific seven transmembrane protein, and matrix metallopeptidase 9. Intracellular signaling pathway analysis revealed that FX specifically decreased the activation of the extracellular signal-regulated kinase and p38 kinase, and increased the nuclear translocation of phosphonuclear factor erythroid 2-related factor 2 (Nrf2). Our results suggest that FX regulates the expression of mitogen-activated protein kinases and Nrf2. Therefore, FX is a potential therapeutic agent for osteoclast-related skeletal disorders including osteoporosis and rheumatoid arthritis. 相似文献
372.
373.
Hae-June Lee Chang-Mo Kang Se-Ra Kim Jong-Choon Kim Chun-Sik Bae Ki-Seok Oh Sung-Kee Jo Tae-Hwan Kim Jong-Sik Jang Sung-Ho Kim 《Journal of veterinary science (Suw?n-si, Korea)》2007,8(2):117-120
Cytogenetic and hematological analyses were performed on the peripheral blood lymphocytes (PBLs) obtained from Korean native cattle bred in the vicinity of three nuclear power plants (Wolsong, Uljin and Yeonggwang) and in a control area. The micronucleus (MN) rates for the cattle from the Wolsong, Uljin and Yeonggwang nuclear power plants and for the control area were 9.87 ± 2.64, 8.90 ± 3.84, 9.20 ± 3.68 and 9.60 ± 3.91 per 1,000 cytokinesis-blocked lymphocytes, respectively. The apparent difference is not statistically significant. The MN frequencies of PBLs from cattle bred in the four areas are within the background variation for this study. The MN frequencies and hematological values were similar regardless of whether the cattle were bred near a nuclear power plant or in the control area. 相似文献
374.
This study was to determine the daily fluctuation of serum thyroxine (tT4), free thyroxine (fT4), 3,5,3''-triiodothyronine (T3) concentrations in healthy dogs. Thyroid function of these dogs was evaluated on the basis of results of TSH response test. Samples for the measurement of serum tT4, fT4, and T3 concentrations were obtained at 3-hour intervals from 8 : 00 to 20 : 00. Serum tT4, fT4, and T3 concentrations were measured by the enzyme chemiluminescent immunoassay (ECLIA). Mean T3 concentrations had no significant differences according to the sample collection time during the day. Mean tT4 and fT4 concentrations at 11 : 00 were 3.28 ± 0.86 µg/dl and 1.30 ± 0.37 ng/dl, respectively and mean tT4 and fT4 at 14:00 were 3.54 ± 1.15 µg/dl and 1.35 ± 0.12 ng/dl, respectively. These concentrations were significantly high compared with tT4 and fT4 concentrations at 8:00, which were 1.75 ± 0.75 µg/dl and 0.97 ± 0.25 ng/dl, respectively (p < 0.05). According to the sample collection time, mean tT4 and fT4 concentrations changed with similar fluctuation during the day. Based on these results, it was considered that measurement of serum tT4 and fT4 concentrations from 11 : 00 to 14 : 00 might more easily diagnose the canine hypothyroidism in practice. 相似文献
375.
Sung Chul Park Jung-Ho Lee Ji-Yeon Hwang Oh-Seok Kwon Lijuan Liao Dong-Chan Oh Ki-Bong Oh Jongheon Shin 《Marine drugs》2021,19(8)
Ochraceopetalin (1), a mixed-biogenetic salt compound and its component 2 were isolated from the culture broths of a marine-derived fungus, Aspergillus ochraceopetaliformis. Based on combined spectroscopic and chemical analyses, the structure of 1 was determined to be a sulfonated diphenylether-aminol-amino acid ester guanidinium salt of an unprecedented structural class, while 2 was determined to be the corresponding sulfonated diphenylether. Ochraceopetaguanidine (3), the other guanidine-bearing aminol amino acid ester component, was also prepared and structurally elucidated. Compound 1 exhibited significant cytotoxicity against K562 and A549 cells. 相似文献
376.
Seung-Taek Oh Woo-Ram Kim Sung-Hoon Kim Yong-Chan Chung Jong-Shin Park 《Fibers and Polymers》2011,12(2):159-165
Polyurethane (PU) foam was combined with protein drug-loaded pH-sensitive alginate-bentonite hydrogel for wound dressings.
Alginate is a linear copolymer composed of 1–4-linked β-D-mannuronic acid (M) and its c-5-epimer α-Lguluronic acid (G). The amount of (M) and (G) and their sequential distribution are varied depending on the alginate source.
Soluble sodium alginate can become a hydrogel when cross-linked with divalent cations and has widespread applications in the
food, drink, pharmaceutical and bioengineering industries. Recently, it has been also proposed as a biomaterial for drug delivery
systems. Bentonites are the natural inorganic polymers consisting of a large proportion of expandable clay minerals with a
three-layer structure such as montmorillonite, beidellite, nontronite, etc. They are important adjutants and supports for
medical products, and they have many useful physicochemical, mechanical, and biological properties such as absence of toxicity,
indifference to other raw materials, sorption, swelling, and complex formation properties. Alginate-bentonite hydrogels were
prepared at concentration ratios of 10/0, 7/3, 5/5, 3/7. PU foams were prepared using hydrophilic polyols. We investigated
the controlled release of a protein drug from PU foam combined with alginate-bentonite hydrogel at different pH values of
4.2, 5.2, 7.2, 8.2. The mechanical properties and cytotoxicity tests of this foam were also studied. 相似文献
377.
Oh MJ Takami I Nishizawa T Kim WS Kim CS Kim SR Park MA 《Journal of fish diseases》2012,35(3):187-191
It was recently reported that Poly(I:C) immunization with live nervous necrosis virus (NNV) confers protection in sevenband grouper, Epinephelus septemfasciatus (Thunberg), from NNV infection. In the present study, we conducted field tests with sevenband grouper for the evaluation of Poly(I:C) immunization efficacy. In the first experiment, sevenband grouper were immunized with NNV followed by Poly(I:C) administration 7 weeks before natural occurrence of viral nervous necrosis (VNN). Survival rate of the naïve fish was 71.0%, whereas that of the immunized fish was 99.8%. In the second experiment, sevenband grouper were immunized 10 months before VNN occurrence and survival rate of the non‐treated and vaccinated fish was 79.5% and 97.5%, respectively. In the third experiment, we administered Poly(I:C) to sevenband grouper at 20 days after natural occurrence of VNN. The survival rate of the non‐treated fish was 9.8%, whereas that of fish administered Poly(I:C) was 93.7%. Based on these results, it was concluded that Poly(I:C) immunization conferred protection in fish against NNV infection in field tests and the protection lasted more than 10 months. Furthermore, even after occurrence of VNN, fish mortality could be reduced by Poly(I:C) administration and there was an unexpected curative effect on VNN‐affected fish. 相似文献
378.
Ultra porous and flexible PET/Aerogel blankets were prepared at ambient pressure, and their acoustic and thermal insulation
properties were characterized. Two methods were selected for the preparation of PET/Aerogel blanket. Method I was a direct
gelation of silica on PET. PET non-woven fabric was dipped and swelled in TEOS/ethanol mixture, and pH of reaction media was
controlled to 2.5 using HCl to promote hydrolysis. After acid hydrolysis, pH was controlled to 7,8,9, and 10 with NH4OH for the condensation. Method II was by the dipping of PET non-woven fabric in the dispersion of Silica hydrogel. The gelation
process was same with Method I. However, PET fabric was not dipped in reaction media. After the hydrogel was dispersed and
aged in EtOH for 24 hrs, then, PET non-woven fabric was dipped in the dispersion of hydrogel/EtOH for 24 hrs. The surface
modification was carried out in TMCS/n-hexane solution, then the blanket was washed with nhexane and dried at room temperature
to prevent the shrinkage. The silica areogels synthesized in optimum conditions exhibit porous network structure. Silica aerogel
of highly homogeneous and smallest spherical particle clusters with pores was prepared by gelation process at pH 7. When direct
gelation of silica was performed in PET nonwoven matrix (Method I), silica aerogel clusters were formed efficiently surrounding
PET fibers forming network structure. The existence of a great amount of silica aerogel of more homogeneous and smaller size
in the cell wall material has positive effect on the sound absorption and thermal insulation. 相似文献
379.
Jessie Gutierrez Chang Oh Hong Byung-Hyun Lee Pil Joo Kim 《Biology and Fertility of Soils》2010,46(6):617-623
The steel-making slag (SMS), a by-product of steel manufacturing process with an alkaline pH (11–12) and high amount of iron
(Fe) and calcium (Ca) oxides, was used to reduce arsenic (As) phytoextractability. The by-product was selected as an alternative
to commercial Fe oxides, which can decrease plant uptake, but they are expensive if used as amendments of contaminated arable
soils. SMS was applied at rates 0, 2, 4, and 8 Mg ha−1 to an As (1 N HCl-extractable As 25 mg kg−1) contaminated soil prepared by mixing non-contaminated soil and mine tailings and cropped to radish (Raphanus sativa L.) seeding. Calcium hydroxide (Ca(OH)2), a common liming material in Korea, was applied at the same rates for comparison. Steel-making slag more effectively suppressed
radish As uptake and increased yield than Ca(OH)2 due to stronger As immobilization because it significantly increased extractable Fe concentration and decreased extractable
As. The SMS-treated soil showed an apparent increase in As chemisorbed by Fe and Al oxides and hydroxides of surface soil,
As associated at the Fe and Al oxides and hydroxides of internal surfaces of soil aggregates, and Ca-associated As. The steel-making
slag can be a good soil amendment to suppress As phytoextractability and improve nutrient balance in As-contaminated soil. 相似文献
380.
Tae Hyung Won Chang-Kwon Kim So-Hyoung Lee Boon Jo Rho Sang Kook Lee Dong-Chan Oh Ki-Bong Oh Jongheon Shin 《Marine drugs》2015,13(6):3836-3848
Four new iodobenzene-containing dipeptides (1–4), a related bromotryptophan-containing dipeptide (5), and an iodophenethylamine (6) were isolated from the ascidian Aplidium sp. collected off the coast of Chuja-do, Korea. The structures of these novel compounds, designated as apliamides A–E (1–5) and apliamine A (6) were determined via combined spectroscopic analyses. The absolute configuration of the amino acid residue in 1 was determined by advanced Marfey’s analysis. Several of these compounds exhibited moderate cytotoxicity and significant inhibition against Na+/K+-ATPase (4). 相似文献