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201.
Jhang Ho Pak Jimin Shin In-Sung Song Sungbo Shim Sung-Wuk Jang 《International journal for parasitology》2017,47(1):51-59
Matrix metalloproteinase-9 plays an important role in the invasion and metastasis of various types of cancer cells. We have previously reported that excretory–secretory products from Clonorchis sinensis increases matrix metalloproteinase-9 expression. However, the regulatory mechanisms through which matrix metalloproteinase-9 expression affects cholangiocarcinoma development remain unclear. In the current study, we examined the potential role of excretory–secretory products in regulating the migration and invasion of various cholangiocarcinoma cell lines. We demonstrated that excretory–secretory products significantly induced matrix metalloproteinase-9 expression and activity in a concentration-dependent manner. Reporter gene and chromatin immunoprecipitation assays showed that excretory–secretory products induced matrix metalloproteinase-9 expression by enhancing the activity of nuclear factor-kappa B. Moreover, excretory–secretory products induced the degradation and phosphorylation of IκBα and stimulated nuclear factor-kappa B p65 nuclear translocation, which was regulated by extracellular signal-regulated kinase 1/2. Taken together, our findings indicated that the excretory–secretory product-dependent enhancement of matrix metalloproteinase-9 activity and subsequent induction of IκBα and nuclear factor-kappa B activities may contribute to the progression of cholangiocarcinoma. 相似文献
202.
Yejin Choi Seong Yi Kwon Ho Jung Oh Sunbo Shim Seokkee Chang Hye Joo Chung Do Keun Kim Younsang Park Younghee Lee 《Biotechnology letters》2017,39(9):1375-1380
Objectives
The single radial immunodiffusion (SRID) assay, used to quantify hemagglutinin (HA) in influenza vaccines, requires reference reagents; however, because centralized production of reference reagents may slow the emergency deployment of vaccines, alternatives are needed.Results
We investigated the production of HA proteins using recombinant DNA technology, rather than a traditional egg-based production process. The HA proteins were then used in an SRID assay as a reference antigen. We found that HA can be quantified in both egg-based and cell-based influenza vaccines when recombinant HAs (rHAs) are used as the reference antigen. Furthermore, we confirmed that rHAs obtained from strains with pandemic potential, such as H5N1, H7N3, H7N9, and H9N2 strains, can be utilized in the SRID assay. The rHA production process takes just one month, in contrast to the traditional process that takes three to four months.Conclusions
The use of rHAs may reduce the time required to produce reference reagents and facilitate timely introduction of vaccines during emergencies.203.
204.
205.
Enzymes that degrade glycosaminoglycans (GAGs) can help reveal the biological roles, structure, and mechanisms of GAGs. We cloned chondroitinase AC, which can degrade chondroitin sulfates A and C, from the genomic library of Bacteroides stercoris HJ-15 isolated from human intestine. The probe (1.4 kb) for the chondroitinase AC gene was prepared from the PCR product of the primers produced using two internal amino acid sequences of chondroitinase AC purified from B. stercoris HJ-15. Using this probe, a chondroitinase AC-positive, 4 kb DNA fragment was selected from pKF3 vector gene libraries containing 2.5–4.5 kb DNA fragments digested with HindIII. The amino acid sequence of the cloned chondroitinase AC showed 41% homology to that of Flavobacterium heparinum. The cloned chondroitinase AC gene was expressed under the T7 promoter of the expression vector, pET-26b(+), in Escherichia coli BL21(DE3) and purified using His bind column chromatography. The expressed chondroitinase AC potently degraded chondroitin sulfates A and C. 相似文献
206.
Novel interactions of ESCRT-III with LIP5 and VPS4 and their implications for ESCRT-III disassembly 总被引:2,自引:1,他引:1
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The AAA+ ATPase VPS4 plays an essential role in multivesicular body biogenesis and is thought to act by disassembling ESCRT-III complexes. VPS4 oligomerization and ATPase activity are promoted by binding to LIP5. LIP5 also binds to the ESCRT-III like protein CHMP5/hVps60, but how this affects its function remains unclear. Here we confirm that LIP5 binds tightly to CHMP5, but also find that it binds well to additional ESCRT-III proteins including CHMP1B, CHMP2A/hVps2-1, and CHMP3/hVps24 but not CHMP4A/hSnf7-1 or CHMP6/hVps20. LIP5 binds to a different region within CHMP5 than within the other ESCRT-III proteins. In CHMP1B and CHMP2A, its binding site encompasses sequences at the proteins' extreme C-termini that overlap with "MIT interacting motifs" (MIMs) known to bind to VPS4. We find unexpected evidence of a second conserved binding site for VPS4 in CHMP2A and CHMP1B, suggesting that LIP5 and VPS4 may bind simultaneously to these proteins despite the overlap in their primary binding sites. Finally, LIP5 binds preferentially to soluble CHMP5 but instead to polymerized CHMP2A, suggesting that the newly defined interactions between LIP5 and ESCRT-III proteins may be regulated by ESCRT-III conformation. These studies point to a role for direct binding between LIP5 and ESCRT-III proteins that is likely to complement LIP5's previously described ability to regulate VPS4 activity. 相似文献
207.
Nayoung Kim Soo‐Heon Park Geom Seog Seo Sang Woo Lee Jae Woo Kim Kwang Jae Lee Won‐Chang Shin Tae Nyeun Kim Moo‐In Park Jong‐Jae Park Su Jin Hong Ki‐Nam Shim Sang Wook Kim Yong‐Woon Shin Young‐Woon Chang Hoon Jai Chun Ok‐Jae Lee Won‐Joong Jeon Chan‐Guk Park Chang‐Min Cho Cheol Hee Park Sun Young Won Gin Hyug Lee Kyung Sik Park Jeong Eun Shin Heung Up Kim Joon Yong Park Hiun Suk Chae Geun Am Song Jae Gyu Kim Byung Chul Yoon Sangyong Seol Hyun Chae Jung In‐Sik Chung 《Helicobacter》2008,13(6):542-549
Background and Aims: Lafutidine is a novel H2‐receptor antagonist with gastroprotective activity that includes enhancement of gastric mucosal blood flow. The aim of the present study was to test the efficacy of 7‐ or 14‐day lafutidine–clarithromycin–amoxicillin therapy versus a lansoprazole‐based regimen for Helicobacter pylori eradication. Methods: Four hundred and sixty‐three patients with H. pylori‐infected peptic ulcer disease were randomized to one of four regimens: (1) lafutidine (20 mg b.i.d.), clarithromycin (500 mg b.i.d.) and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LFT group) or (2) for 14 days (the 14LFT group); (3) lansoprazole (30 mg b.i.d.), clarithromycin (500 mg b.i.d.), and amoxicillin (1000 mg b.i.d.) for 7 days (the 7LPZ group); or (4) for 14 days (the 14LPZ group). The eradication rates, drug compliance, and adverse effects among the four regimens were compared. Results: The eradication rates by the intention‐to‐treat and per‐protocol analyses in the 7LFT and 7LPZ groups were 76.5% and 81.6%, and 76.9% and 82.0% (p = .94 and .95), respectively. The eradication rates by intention‐to‐treat and per‐protocol analyses in the 14LFT and 14LPZ groups were 78.2% and 82.2%, and 80.4% and 85.9% (p = .70 and .49), respectively. The treatment duration for 7 days or 14 days did not affect the eradication rates. In addition, the adverse effect rates and discontinuation rates were similar among the four groups. Furthermore, the ulcer cure rate and symptom response rate were similar in the lafutidine and lansoprazole groups. Conclusion: The results of this study showed that lafutidine–clarithromycin–amoxicillin therapy was a safe and effective as lansoprazole‐based triple therapy for the eradication rate of H. pylori, and could be considered as an additional treatment option. 相似文献
208.
Sang-Gyu Seo Seung-Won Kang Ie-Sung Shim Wook Kim Shinsuke Fujihara 《Plant Growth Regulation》2009,57(3):251-258
To understand the factors that induce floral senescence in Hibiscus syriacus L., we have investigated the effects of various chemical agents on flower senescence at two different flowering stages, before
and after full bloom, as well as the relationship between flower longevity and endogenous ethylene production before full
bloom. Treatments with ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), and ethephon enhanced floral senescence, while
aminoethoxyvinylglycine (AVG) promoted flower longevity regardless of treatment timing. Although ethanol slightly extended
flower longevity, abscisic acid (ABA), nitric oxide, boric acid and sucrose, which have been reported to affect flower longevity
or senescence, had no effect on H. syriacus floral senescence. The polyamine spermine (SPM), methylglyoxal-bis(guanylhydrazone) (MGBG), an inhibitor of SPM biosynthesis,
and cycloheximide (CHI) accelerated flower senescence when applied before full bloom, but had no effect when applied after
full bloom. SPM, MGBG and CHI treatments resulted in enhanced ethylene production during flower opening, and the promotion
of flower senescence is mediated by ethylene production prior to full bloom. Furthermore, endogenous ethylene, spontaneously
produced before blooming, was closely associated with floral senescence. These results suggest that ethylene production during
flower opening plays a key role in determining the timing of Hibiscus flower senescence. 相似文献
209.
J. I. Chae S. K. Ju M. K. Lee J. H. Park J. H. Yoon J. H. Shim D. S. Lee 《Molecular Biology》2009,43(1):82-87
The corticotropin-releasing hormone (CRH) family of neuropeptides includes CRH (a 41-amino acid hypothalamic peptide) and urocortin. Corticotropin-releasing factor (CRF), a peptide first isolated from mammalian, plays an important role in the regulation of the pituitary-adrenal axis, and in endocrine, autonomic, immune and behavioral responses to stress. In this study, we cloned rat urocortin II (UCN II) cDNA from rat mid-brain by RT-PCR. The rat UCN II clone contained an open reading frame (ORF) 109 amino acids which shared 90% and 63% homology with mouse and human homologues, respectively. The expression of UCN II mRNA is mainly distributed in bone marrow, ovary, uterus, hypophysis, adrenal gland, and skin. In this study, rat recombinant UCN was expressed in E. coli and purified in active form. Furthermore, purified recombinant UCN II protein specifically binds to CRF receptor 2 in rat ROS 17 / 2.8 and GH3 cells by flow-cytometry analysis. UCN II cDNA clone obtained in this study will be useful for further investigation on behavioral responses to stress in rats. 相似文献
210.
Wei Choon Alvin Koh Eun Sang Choe Dong Kun Lee Seung-Cheol Chang Yoon-Bo Shim 《Biosensors & bioelectronics》2009,25(1):211-217
An all solid state potentiometric immunosensor (ASPI) has been developed to study the activation process of neuronal nitric oxide synthase (nNOS), the enzyme involved in the synthesis of nitric oxide generated under physiological conditions. At first, an all solid state H+-selective ISE was fabricated with the carboxylated poly(vinyl chloride) (PVC-COOH) film containing H+ ionophore, antibody was then immobilized on the polymer layer. The immunocomplex formation was detected by monitoring pH change due to interaction between urease labeled secondary antibody and antigen. Experimental parameters such as the amount of phosphorylated nNOS immobilized on the electrode surface and pH responses due to the antibody–antigen reaction were studied in detail. The calibration plot of the potentiometric potential vs. phosphorylated nNOS concentration exhibited a linear relationship in the range of 3.4–340.0 μg/ml. The calibration sensitivity of the phosphorylated nNOS immunosensor was −0.073 ± 0.002 mV/μg ml−1. The detection limit of nNOS was determined to be 0.2 μg/ml based on five-time measurements (95% confidence level, k = 3, n = 5). The reliability of the immunosensor was examined with rat brain tissues as well as neuronal cells, and the results shown were good, implying a promising approach for a novel electrochemical immunosensor platform with potential applications to clinical diagnosis. 相似文献