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51.
Yong-Hun Park Sang Keun Ha Inwook Choi Kyu Sik Kim Jeryang Park Nakwon Choi Bumsang Kim Jong Hwan Sung 《Biotechnology and Bioprocess Engineering》2016,21(1):110-118
Transdermal drug delivery system (TDDS) may provide a more reliable method of drug delivery than oral delivery by avoiding gut absorption and first-pass metabolism, but needs a method for efficiently crossing the epidermal barrier. To enhance the delivery through the skin, we have developed a biocompatible, dissolvable microneedle array made from carboxymethyl cellulose (CMC). Using laser ablation for creating the mold greatly improved the efficiency and reduced the cost of microneedle fabrication. Mixing CMC with amylopectin (AP) enhanced the mechanical and tunable dissolution properties of the microneedle for controlled release of model compounds. Using the CMC microneedle array, we observed significant enhancement in the skin permeability of a fluorescent model compound, and also increase in the anti-oxidant activity of ascorbic acid after crossing the skin. Our dissolvable microneedle array provides a new and biocompatible method for delivery of drugs and cosmetic compounds through the skin. 相似文献
52.
MCPIP1 ribonuclease antagonizes dicer and terminates microRNA biogenesis through precursor microRNA degradation 总被引:2,自引:0,他引:2
Suzuki HI Arase M Matsuyama H Choi YL Ueno T Mano H Sugimoto K Miyazono K 《Molecular cell》2011,44(3):424-436
MicroRNAs (miRNAs) are versatile regulators of gene expression and undergo complex maturation processes. However, the mechanism(s) stabilizing or reducing these small RNAs remains poorly understood. Here we identify mammalian immune regulator MCPIP1 (Zc3h12a) ribonuclease as a broad suppressor of miRNA activity and biogenesis, which counteracts Dicer, a central ribonuclease in miRNA processing. MCPIP1 suppresses miRNA biosynthesis via cleavage of the terminal loops of precursor miRNAs (pre-miRNAs). MCPIP1 also carries a vertebrate-specific oligomerization domain important for pre-miRNA recognition, indicating its recent evolution. Furthermore, we observed potential antagonism between MCPIP1 and Dicer function in human cancer and found a regulatory role of MCPIP1 in the signaling axis comprising miR-155 and its target c-Maf. These results collectively suggest that the balance between processing and destroying ribonucleases modulates miRNA biogenesis and potentially affects pathological miRNA dysregulation. The presence of this abortive processing machinery and diversity of MCPIP1-related genes may imply a dynamic evolutional transition of the RNA silencing system. 相似文献
53.
Free Flow Electrophoresis (FFE) is a liquid-based isoelectric focusing method. Unlike conventional in-gel fractionation of proteins, FFE can resolve proteins in their native forms and fractionation of subcellular compartments of the cell is also possible. To test the efficacy of the FFE method, the native cytosol proteome of a bacterium, Pseudomonas putida KT2440 was fractionated by FFE and the spectrum of protein elutes was characterized in association with 2-dimentional gel electrophoresis (2-DE). Major native proteins of P. putida KT2440 were eluted in the range of pH 4.8 approximately 6.0 in FFE, whereas the denatured proteome of P. putida KT2440 was widely distributed in the rage of pH 4 approximately 10 in the 2-DE analysis. In addition, one of the three FFE major fractions, which was eluted at pH 5.0, was further analyzed using 2-DE/MS-MS. Then, the pH range of identified proteins eluted in 2-DE/MS-MS was 4.72 approximately 5.89, indicating that observed pi values of native cytosolic proteomes in FFE were narrower than those of denatured cytosolic proteome. These results suggest that FFE fractionation and 2-DE/MS analysis may be useful tools for characterization of native proteomes of P. putida KT2440 and comparative analysis between denatured and native proteomes. 相似文献
54.
Lan Phi NT Nishiyama C Choi HS Sawamura M 《Bioscience, biotechnology, and biochemistry》2006,70(8):1832-1838
The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by gamma-terpinene (5.30%), myrcene (2.25%) and alpha-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, alpha-pinene, beta-pinene, limonene, nonanal, gamma-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 3(6)), whereas beta-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil. 相似文献
55.
SN Park SW Kong MS Park JW Lee E Cho YK Lim MH Choi HS Kim YH Chang JH Shin HS Park SH Choi JK Kook 《Journal of bacteriology》2012,194(19):5445-5446
Fusobacterium nucleatum, one of the major causative bacteria of periodontitis, is classified into five subspecies (nucleatum, polymorphum, vincentii, animalis, and fusiforme) on the basis of the several phenotypic characteristics and DNA homology. This is the first report of the draft genome sequence of F. nucleatum subsp. fusiforme ATCC 51190(T). 相似文献
56.
Tissue-specific expression of betaKlotho and fibroblast growth factor (FGF) receptor isoforms determines metabolic activity of FGF19 and FGF21 总被引:3,自引:0,他引:3
Kurosu H Choi M Ogawa Y Dickson AS Goetz R Eliseenkova AV Mohammadi M Rosenblatt KP Kliewer SA Kuro-o M 《The Journal of biological chemistry》2007,282(37):26687-26695
57.
In this study, the role of Toll‐like receptor 2 (TLR2) in immune responses of murine peritoneal mesothelial cells against Bacteroides fragilis was investigated. Enzyme linked immunosorbent assay was used to measure cytokines and chemokines. Activation of nuclear factor κB (NF‐κB‐α) and mitogen‐activated protein kinases (MAP kinases) was investigated by western blot analysis. B. fragilis induced production of interleukin‐6, chemokine (C‐X‐C motif) ligand 1 (CXCL1) and chemokine (C‐C motif) ligand 2 (CCL2) in wild type peritoneal mesothelial cells; this was impaired in TLR2‐deficient cells. In addition, in response to B. fragilis, phosphorylation of inhibitory NF‐κB‐α and c‐Jun N‐terminal kinase mitogen‐activated protein kinase (MAPK) was induced in wild type mesothelial cells, but not in TLR2‐deficient cells,. Inhibitor assay revealed that NF‐κB and MAPKs are essential for B. fragilis‐induced production of CXCL1 and CCL2 in mesothelial cells. These findings suggest that TLR2 mediates immune responses in peritoneal mesothelial cells in response to B. fragilis. 相似文献
58.
Currently, obesity is considered a systemic inflammation; however, the effects of obesity on the vulnerability of dopaminergic neurons to oxidative stress are not fully defined. We evaluated the effects of high-fat diet-induced obesity (HF DIO) on neurotoxicity in mice treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Eight weeks after a HF or matched normal diet, a severe decrease in the levels of striatal dopamine and of nigral microtubule-associated protein 2, manganese superoxide dismutase, and tyrosine hydroxylase was observed in obese mice treated with subtoxic doses of MPTP (20 mg/kg) compared with the matched lean group. In addition, the levels of nitrate/nitrite and thiobarbituric acid-malondialdehyde adducts in the substantia nigra of obese mice were reciprocally elevated or suppressed by MPTP. Interestingly, striatal nNOS phosphorylation and dopamine turnover were elevated in obese mice after MPTP treatment, but were not observed in lean mice. The nitrotyrosine immunoreactivity for evaluation of nigral nitrogenous stress in obese mice with MPTP was higher than that in matched lean mice. At higher doses of MPTP (60 mg/kg), the mortality was higher in obese mice than in lean mice. These results suggest that DIO may increase the vulnerability of dopaminergic neurons to MPTP via increased levels of reactive oxygen and nitrogen species, and the role of nNOS phosphorylation in the MPTP toxicities and dopamine homeostasis should be further evaluated. 相似文献
59.
60.
Sunkyu Choi Kun Cho Kyungmoo Yea Jeonghwa Lee Jeongkwon Kim 《Biochemical and biophysical research communications》2009,383(1):135-140
Hypoxia during the expansion of adipocytes is known to contribute both to the secretion of multiple inflammation-related adipokines as well as to obesity. We therefore investigated the nature of protein changes occurring in adipocytes during hypoxia by observation of the intracellular proteins that are expressed in 3T3-L1 adipocytes. Lysates were utilized for quantitative proteome analysis using isobaric tags for relative and absolute quantitation (iTRAQ) combined with peptide separation by multi-dimensional liquid chromatography. Antioxidants and elongation factors, as well as glycolytic enzymes were increased in hypoxic adipocytes. These changes were supported by similar changes suggested by real-time PCR. The proteins showing changes are all potential targets for revering the mechanism behind the phenomenon of induction of obese adipocytes by hypoxia. This study can therefore aid in defining the proteomic changes that occur in adipocytes in response to oxygen stress, and can further characterize adipocyte metabolism and adaptation to low oxygen conditions. 相似文献