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951.
Mi-Young Song Gil-Saeng Jeong Kang-Beom Kwon Sun-O Ka Hyun-Young Jang Jin-Woo Park Youn-Chul Kim Byung-Hyun Park 《Experimental & molecular medicine》2010,42(9):628-638
NF-κB activation has been implicated as a key signaling mechanism for pancreatic β-cell damage. Sulfuretin is one of the main flavonoids produced by Rhus verniciflua, which is reported to inhibit the inflammatory response by suppressing the NF-κB pathway. Therefore, we isolated sulfuretin from Rhus verniciflua and evaluated if sulfuretin could inhibit cytokine- or streptozotocin-induced β-cell damage. Rat insulinoma RINm5F cells and isolated rat islets were treated with IL-1β and IFN-γ to induce cytotoxicity. Incubation of cells and islets with sulfuretin resulted in a significant reduction of cytokine-induced NF-κB activation and its downstream events, iNOS expression, and nitric oxide production. The cytotoxic effects of cytokines were completely abolished when cells or islets were pretreated with sulfuretin. The protective effect of sulfuretin was further demonstrated by normal insulin secretion of cytokine-treated islets in response to glucose. Treatment of mice with streptozotocin resulted in hyperglycemia and hypoinsulinemia, which was further evidenced by immunohistochemical staining of islets. However, the diabetogenic effects of streptozotocin were completely prevented when mice were pretreated with sulfuretin. The anti-diabetogenic effects of sulfuretin were also mediated by suppression of NF-κB activation. Collectively, these results indicate that sulfuretin may have therapeutic value in preventing β-cell damage. 相似文献
952.
953.
Sundo Jung Yoon-Kyung Park Hyunji Lee Jung Hoon Shin Gap Ryol Lee Se-Ho Park 《Experimental & molecular medicine》2010,42(3):187-194
Collagen-induced arthritis (CIA) is mediated by self-reactive CD4+ T cells that produce inflammatory cytokines. TGF-β2-treated tolerogenic antigen-presenting cells (Tol-APCs) are known to induce tolerance in various autoimmune diseases. In this study, we investigated whether collagen-specific Tol-APCs could induce suppression of CIA. We observed that Tol-APCs could suppress the development and severity of CIA and delay the onset of CIA. Treatment of Tol-APCs reduced the number of IFN-γ- and IL-17-producing CD4+ T cells and increased IL-4- and IL-5-producing CD4+ T cells upon collagen antigen stimulation in vitro. The suppression of CIA conferred by Tol-APCs correlated with their ability to selectively induce IL-10 production. We also observed that treatment of Tol-APCs inhibited not only cellular immune responses but also humoral immune responses in the process of CIA. Our results suggest that in vitro-generated Tol-APCs have potential therapeutic value for the treatment of rheumatoid arthritis as well as other autoimmune diseases. 相似文献
954.
Min Kyong Moon Min Kim Sung Soo Chung Hyun Joo Lee Sung Hee Koh Peter Svovoda Myung Hee Jung Young Min Cho Young Joo Park Sung Hee Choi Hak Chul Jang Kyong Soo Park Hong Kyu Lee 《Experimental & molecular medicine》2010,42(5):345-352
An association between inflammatory processes and the pathogenesis of insulin resistance has been increasingly suggested. The IκB kinase-β (IKK-β)/ nuclear factor-κB (NF-κB) pathway is a molecular mediator of insulin resistance. S-Adenosyl-L-methionine (SAM) has both antioxidative and anti-inflammatory properties. We investigated the effects of SAM on the glucose transport and insulin signaling impaired by the tumor necrosis factor α (TNFα) in 3T3-L1 adipocytes. SAM partially reversed the basal and insulin stimulated glucose transport, which was impaired by TNFα. The TNFα-induced suppression of the tyrosine phosphorylation of the insulin receptor substrate-1 (IRS-1) and Akt in 3T3-L1 adipocytes was also reversed by SAM. In addition, SAM significantly attenuated the TNFα-induced degradation of IκB-α and NF-κB activation. Interestingly, SAM directly inhibited the kinase activity of IKK-β in vitro. These results suggest that SAM can alleviate TNFα mediated-insulin resistance by inhibiting the IKK-β/NF-κB pathway and thus can have a beneficial role in the treatment of type 2 diabetes mellitus. 相似文献
955.
Chen X Nam SW Kim GH Song N Jeong Y Shin I Kim SK Kim J Park S Yoon J 《Chemical communications (Cambridge, England)》2010,46(47):8953-8955
A new NIR fluorescent sensor based on an amine-substituted heptamethine cyanine dye displayed a highly selective fluorescence enhancement with cyanide in aqueous solutions, and was applied for the imaging of anthropogenic and biogenic cyanide. 相似文献
956.
Jin Young Park Hong Chae Jung G. Seeta Rama Raju Byung Kee Moon Jung Hyun Jeong Jung Hwan Kim 《Solid State Sciences》2010,12(5):719-724
A series of Eu3+ ions co-doped (Gd0.9Y0.1)3Al5O12:Bi3+, Tb3+ (GYAG) phosphors have been synthesized by means of solvothermal reaction method. The XRD pattern of GYAG phosphor sintered at 1500 °C confirms their garnet phase. The luminescence properties of these phosphors have been explored by analyzing their excitation and emission spectra along with their decay curves. The excitation spectra of the GYAG:Bi3+, Tb3+, Eu3+ phosphors consists of broad bands in the shorter wavelength region due to 4f8 → 4f75d1 transition of Tb3+ ions overlapped with 6s2 → 6s16p1 (1S0 → 3P1) transition of Bi3+ ions and the charge transfer band of Eu3+–O2?. The present phosphors exhibit green and red colors due to 5D4 → 7F5 transition of Tb3+ ions and 5D0 → 7F1 transition of Eu3+ ions, respectively. The emission was shifted from green to red color by co-doping with Eu3+ ions, which indicate that the energy transfer probability from Tb3+ to Eu3+ ions are dependent strongly on the concentration of Eu3+ ions. 相似文献
957.
Jo E Jhon YH Choi SB Shim JG Kim JH Lee JH Lee IY Jang KR Kim J 《Chemical communications (Cambridge, England)》2010,46(48):9158-9160
A crystal structure of a carbamate of 2-amino-2-methyl-1-propanol (AMP-carbamate) has been elucidated and its structural and electronic properties investigated by density functional theory calculations and natural bond orbital analyses. 相似文献
958.
Kim YR Kim HJ Lee MH Kang YJ Yang Y Kim H Kim JS 《Chemical communications (Cambridge, England)》2010,46(44):8448-8450
We demonstrate electrochemically controlled release of chemodosimeters attached to ultrathin patterned platinum electrodes. Fluorescence and electrochemical methods have been employed for the detection of chemodosimeter modification/desorption and Cu(2+) binding/removal. 相似文献
959.
Hwangseo Park 《Journal of computational chemistry》2010,31(5):897-903
Backbone–backbone hydrogen bonds (BBHBs) are one of the most abundant interactions at the interface of protein–protein complex. Here, we propose an angle‐dependent potential energy function for BBHB based on density functional theory (DFT) calculations and the operation of a genetic algorithm to find the optimal parameters in the potential energy function. The angular part of the energy funtion is assumed to be the product of the power series of sine and cosine functions with respect to the two angles associated with BBHB. Two radial functions are taken into account in this study: Morse and Leonard‐Jones 12‐10 potential functions. Of these two functions under consideration, the former is found to be more accurate than the latter in terms of predicting the binding energies obtained from DFT calculations. The new HB potential function also compares well with the knowledge‐based potential derived by applying Boltzmann statistics for a variety of protein–protein complexes in protein data bank. © 2009 Wiley Periodicals, Inc. J Comput Chem, 2010 相似文献
960.
Hwan-Seo Park In-Tae Kim Yong-Jun Cho Mi-Sook Son Hee-Chul Eun 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(2):267-272
Radioactive molten salt generated from a pyrochemical process to separate reusable U and TRU elements is one of problematic
wastes to manage for a final disposal. For the minimization of final waste, it is desirable to selectively remove radionuclides
from the waste salts. In this paper, structural change of some zeolites in a series of molten salt systems and its removal
behavior of CsCl was investigated. Zeolite-4A(LTA) was transformed into LiAlSiO4 and Li-sodalite with the mol-fraction of LiCl in LiCl–KCl system at 650 °C while it was not changed in NaCl–KCl at 750 °C,
regardless of mol-fraction of metal chloride. Other commercial zeolite with specific structure (FAU) had the same trends on
the structural stability in molten salt system. From the Cs removal experiments, the decomposed zeolitic materials in molten
salt lost their removal ability of Cs. In conclusion, a new selective material or method should be investigated or developed
for obtaining the validity on the separation of group I and II radionuclides from a molten waste salt because the zeolite
4A is unstable in the LiCl system and it also showed a low capacity in the LiCl–KCl phase. This paper gives basic information
on the removal of radionuclides from molten systems by using zeolitic materials. 相似文献