• Molecules and Cells
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• v.41 no.6
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• pp.591-602
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• 2018

Gastric cancer is the fifth most common type of malignancy worldwide, and the survival rate of patients with advanced-stage gastric cancer is low, even after receiving chemotherapy. Here, we validated neurotensin receptor 1 (NTSR1) as a potential therapeutic target in gastric cancer. We compared NTSR1 expression levels in sixty different gastric cancer-tissue samples and cells, as well as in other cancer cells (lung, breast, pancreatic, and colon), by assessing NTSR1 expression via semi-quantitative real-time reverse transcription polymerase chain reaction, immunocytochemistry and western blot. Following neurotensin (NT) treatment, we analyzed the expression and activity of matrix metalloproteinase-9 (MMP-9) and further determined the effects on cell migration and invasion via wound-healing and transwell assays. Our results revealed that NTSR1 mRNA levels were higher in gastric cancer tissues than non-cancerous tissues. Both of NTSR1 mRNA levels and expression were higher in gastric cancer cell lines relative to levels observed in other cancer-cell lines. Moreover, NT treatment induced MMP-9 expression and activity in all cancer cell lines, which was significantly decreased following treatment with the NTSR1 antagonist SR48692 or small-interfering RNA targeting NTSR1. Furthermore, NT-mediated metastases was confirmed by observing epithelial-mesenchymal transition markers SNAIL and E-cadherin in gastric cancer cells. NT-mediated invasion and migration of gastric cancer cells were reduced by NTSR1 depletion through the Erk signaling. These findings strongly suggested that NTR1 constitutes a potential therapeutic target for the inhibition of gastric cancer invasion and metastasis.

• KSBB Journal
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• v.16 no.2
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• pp.146-152
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• 2001

To avoid the intrinsic problem of aggregation associated with the traditional solution-phase refolding process, we propose a solid-phase refolding method integrated with expanded bed adsorption chromatography. The model protein used was a fusion protein of recombinant human growth hormone and a glutathione S transferase fragment. It was demonstrated that the EBA-mediated refolding technique could simultaneously remove cellular debris and directly renature the fusion protein inclusion bodies in the cell homogenate with much higher yields and less agregation. To demonstrate the applicability of the method, we successfully tested the three representative types of starting materials, i. e., rhGH monomer, washed inclusion bodies, and the E. coli homogenate. This direct and simplified refolding process could also reduce the number of renaturation steps required and allow refolding at a higher concentration, at approximately 2 mg fusion protein per ml of resin. To the best of our knowledge, it is the first approach that has combined the solid-phase refolding method with expanded bed chromatography.

• The Korean Journal of Applied Statistics
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• v.30 no.1
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• pp.1-12
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• 2017

Many stochastic processes satisfy the Markov property exactly or at least approximately. An interested property in the Markov process is the first passage time. Since the sequential analysis by Wald, the approximation of the first passage time has been studied extensively. The Statistical computing technique due to the development of high-speed computers made it possible to calculate the values of the properties close to the true ones. This article introduces an exponentially weighted moving average (EWMA) control chart as an example of the Markov process, and studied how to calculate the average run length with problematic issues that should be cautioned for correct calculation. The results derived for approximation of the first passage time in this research can be applied to any of the Markov processes. Especially the approximation of the continuous time Markov process to the discrete time Markov chain is useful for the studies of the properties of the stochastic process and makes computational approaches easy.

• Archives of Plastic Surgery
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• v.34 no.2
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• pp.149-155
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• 2007

Purpose: This study was to investigate how the heparin, which has been known to induce neovascularization by MMP in the infarcted tissue of the myocardium, had influence on the expression of mRNA of MMP 1,2,9 of the skin wound of rat. Methods: Full depth skin wounds were created on the dorsum of Sprague-Dawley 60 rats. The experimental rats were divided into two groups according to the concentration of heparin($100{\mu}g/ml$ in 20, $300{\mu}g/ml$ in 20). Heparin soaked gelatin sponges in different concentration were inserted into the pocket of experimental rats and the wounds were closed. Normal saline soaked gelatin sponges were used in control rats. Wounds were harvested at 48 and 72 hours after closure. We performed histologic study in H-E stain. RNA was isolated from the harvested tissue and then real time polymerase chain reaction was performed to determine the gene expression of MMP-1,2,9. Results: We observed that inflammatory cell decreased in heparin soaked group and heparin increased the expression of MMP-1,9 mRNA of dorsal wound of rat at 72 hours (p < 0.05). Conclusion: This result suggest that heparin may be used inducing another factor inducing scarless wound healing by increasing MMP.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.447-452
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• 2006

To determine the functions of specific cell wall polysaccharides, polysaccharides of three mutants, mur3-1, mur3-2, and mur3-3, obtained from Arabidopsis wild type, underwent structural characterization. Upon sequential separation of pectins (RG-I and RG-II) and cross-linking glycans (xyloglucan, XG), only XG was affected by the mud mutation. Wild-type XG contained a considerable amount of fucose, whereas the fucose level in mur3 XGs was less than 20% that of wild type. Further analysis of XGs by matrix-assisted laser-induced/ionization time-of-flight (MALDI-TOF) mass spectrometry indicated that mud lines considerably or completely lost the fucosylated XG oligosaccharides such as XXFG and XLFG and the double-galactosylated oligosaccharide XLLG $^1H$-NMR spectroscopic analyses of the XG oligosaccharides from mur3-3 plant revealed the absence of fucose and a galactose level in the galactosylated side chain that was reduced by 40% compared to that of Arabidopsis wild-type plant. In contrast, 85% less fucose and a slight loss of galactose were observed in the mur3-1 and mur3-2 lines which show normal growth habit. Of the three Arabidopsis mur3 lines studied here, mur3-3 is disrupted by a T-DNA insertion in the exon of MUR3 which encodes XG-specific galactosyltransferase, and exhibits slight dwarfism. These results indicated that the T-DNA insertion at the MUR3 locus did not induce the complete loss of galactose in XG, and that galactose, rather than fucose, in the XG side chains made a major contribution to overall wall strength.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.53-58
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• 2006

MicroRNA (miRNA)는 약 22 nt의 작은 RNA 조각으로 이루어져 있으며 stem-loop 구조의 precursor 형태에서 최종적으로 만들어 진다. miRNA는 mRNA의 3‘UTR에 상보적으로 결합하여 유전자의 발현을 억제하거나 mRNA의 분해를 촉진한다. miRNA를 동정하기 위한 실험적인 방법은 조직 특이적인 발현, 적은 발현양 때문에 방법상 한계를 가지고 있다. 이러한 한계는 컴퓨터를 이용한 방법으로 어느 정도 해결될 수 있다. 하지만 miRNA의 서열상의 낮은 보존성은 homology를 기반으로 한 예측을 어렵게 한다. 또한 기계학습 방법인 support vector machine (SVM) 이나 naive bayes가 적용되었지만, 생물학적인 의미를 해석할 수 있는 generative model을 제시해 주지 못했다. 본 연구에서는 우수한 miRNA 예측을 보일 뿐만 아니라 학습된 모델로부터 생물학적인 지식을 얻을 수 있는 Bayesian network을 적용한다. 이를 위해서는 생물학적으로 의미 있는 특질들의 선택이 중요하다. 여기서는 position weighted matrix (PWM)과 Markov chain probability (MCP), Loop 크기, Bulge 수, spectrum, free energy profile 등을 특질로서 선택한 후 Information gain의 특질 선택법을 통해 예측에 기여도가 높은 특질 25개 와 27개를 최종적으로 선택하였다. 이로부터 Bayesian network을 학습한 후 miRNA의 예측 성능을 10 fold cross-validation으로 확인하였다. 그 결과 pre-/mature miRNA 각 각에 대한 예측 accuracy가 99.99% 100.00%를 보여, SVM이나 naive bayes 방법보다 높은 결과를 보였으며, 학습된 Bayesian network으로부터 이전 연구 결과와 일치하는 pre-miRNA 상의 의존관계를 분석할 수 있었다.

• Annals of dermatology
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• v.30 no.6
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• pp.694-700
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• 2018

Background: Kaempferol (3,4',5,7-tetrahydroxyflavone) is a flavonoid known to have a wide range of pharmacological activities. The 3-OH group in flavonoids has been reported to determine antioxidant activities. Objective: We tested whether kaempferol can affect the expression of integrins and the stem cell fate of interfollicular epidermal stem cells. Methods: Skin equivalent (SE) models were constructed, and the expression levels of stem cell markers and basement membrane-related antigens were tested. The immunohistochemical staining patterns of integrins, p63, and proliferating cell nuclear antigen (PCNA) were compared between kaempferol- and apigenin-treated SE models. Reverse transcription-polymerase chain reaction (RT-PCR) was used to evaluate the mRNA expression of integrins. Results: Kaempferol increased the thickness of the epidermis when added to prepare SEs. In addition, the basal cells of kaempferol-treated SEs appeared more columnar. In the immunohistological study, the expression of integrins ${\alpha}6$ and ${\beta}1$ and the numbers of p63- and PCNA-positive cells were markedly higher in the kaempferol-treated model. However, apigenin showed no effects on the formation of three-dimensional skin models. RT-PCR analysis also confirmed that kaempferol increased the expression of integrin ${\alpha}6$ and integrin ${\beta}1$. Conclusion: Our findings indicated that kaempferol can increase the proliferative potential of basal epidermal cells by modulating the basement membrane. In other words, kaempferol can affect the fate of interfollicular epidermal stem cells by increasing the expression of both integrins ${\alpha}6$ and ${\beta}1$. These effects, in particular, might be ascribed to the 3-OH group of kaempferol.

• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.713-717
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• 1993

The crystal structure of the potassium salt of penicillin V has been studied by the X-ray crystallographic methods. Crystal data are as follows; potassium 3,3-dimethyl-7-oxo-6-phenoxyacetoamido-4-thia-1- azabicyclo[3.2.0]-heptane-2${\alpha}$-carboxylate, $K^+{\cdot}C_{16}H_{18}N_2O_5S^-$, $M_r$= 388.5, triclinic, Pl, a= 9.371 (1), b= 12.497 (2), c= 15.313 (2) ${\AA},\;{\alpha}= 93.74\;(2),\;{\beta}=99.32\;(1),\;{\gamma}=90.17\;(1)^{\circ},\;V=1765.7\;(2)\;{\AA}^3$, Z=4, $D_m=1.461\;gcm^{-1},\;{\lambda}(Cu\;K{\alpha})=1.5418\;{\AA},\;{\mu}=40.1\;cm^{-1}$, F(000)=808, T=296 K. The structure was solved by the heavy atom and difference Fourier methods with intensity data measured on an automated four-circle diffractometer. The structure was refined by the full-matrix least-squares method to a final R= 0.081 for 3563 observed $[I_0{\geq}2{\sigam}(I_0)]$ reflections. The four independent molecules assume different overall conformations with systematically different orientations of the phenyl groups although the penam moieties have the same closed conformations. There are intramolecular hydrogen bonds between the exocyclic amide nitrogen and phenoxy oxygen atoms. The penam moiety is conformationally very restricted although the carboxyl and exocyclic amide groups apparently have certain rotational degrees of freedom but the phenyl group is flexible about the ether bond despite the presence of the intramolecular N-H${\cdots}$O hydrogen bond. There are complicated pseudo symmetric relationships in the crystal lattice. The penam moieties are related by pseudo 20.5 screw axes and the phenyl groups by pseudo centers of symmetry. The potassium ions, related by both pseudo symmetries, form an infinite zigzag planar chain parallel to the b axis. Each potassium ion is coordinated to seven oxygen atoms in a severely distorted pentagonal bipyramid configuration, forming the infinite hydrophilic channels which in turn form the molecular stacks. Between these stacks, there are only lipophilic interactions involving the phenyl groups.

• Journal of Korean Medicine Rehabilitation
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• v.29 no.2
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• pp.135-147
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• 2019

Objectives This study was performed to evaluate the effect of Pyrola japonica extract (NJ) and its principal constituent, homoarbutin (HA) on osteoclast differentiation and gene expression and bone resorption. The osteoclastogenesis and gene expression were determined in receptor activator of nuclear factor kappa B ligand (RANKL)-stimulated RAW264.7 cell. Methods In order to evaluate the effect of HA extracted from NJ on bone resorption, osteoclasts were used to be differentiated and formed by stimulating RAW264.7 cells with RANKL. Tartarate-resistant acid phosphatase (TRAP) (+) polynuclear osteoclast formation ability was evaluated, and differentiation control genes including cathepsin K, matrix metalloproteinases-9 (MMP-9), and TRAP in osteoclast differentiation were analyzed by real-time polymerase chain reaction (PCR). Immunoblotting was performed to measure the effect of mitogen-activated protein kinase (MAPK) factors on bone resorption, and the effect of osteoclasts on osteoclast differentiation was measured. Results Both NJ and high concentration of HA blocked RANKL-stimulated differentiation from RAW264.7 cell to TRAP-positive multinucleated cells. NJ reduced RANKL-induced expression of TRAP, cathepsin K. Both NJ and high concentration of HA inhibited RANKL-mediated expression of MMP-9, nuclear factor of activated T-cells, cytoplasmic 1, and cellular Jun-fos. NJ suppressed RANKL-stimulated expression of cyclooxygenase-2 (COX-2), inducible nitric oxide synthase, tumor necrosis factor-alpha, and levels of interleukins. Both NJ and HA decreased bone resorption in osteoclast-induced bone pit formation model. Conclusions These results suggest that NJ and HA blocked bone resorption by decreasing RANKL-mediated osteoclastogenesis through down-regulation of genes for osteoclast differentiation.

• Ocean and Polar Research
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• v.40 no.4
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• pp.249-257
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• 2018

Matrix metalloproteinases (MMPs) are associated with the invasion and metastasis of malignant tumors composed of cancer cells in an increased state of expression. This study evaluates the inhibitory effect of Carex pumila on MMP-2 and MMP-9 activity in phorbol-12-myristate-13-acetate (PMA)-stimulated HT-1080 human fibrosarcoma cells using gelatin zymography, MMPs enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay. C. pumila was extracted twice with dichloromethane ($CH_2Cl_2$) and methanol (MeOH). Treatment with $CH_2Cl_2$ extract and MeOH extract in PMA-stimulated HT-1080 cells effectively reduced the production of MMP-2 and 9. Also, the combined crude extracts ($CH_2Cl_2$ and MeOH) significantly inhibited the enzymatic activities and the expression of MMP-2 and MMP-9 in mRNA and protein levels. The combined crude extracts were partitioned between $CH_2Cl_2$ and water. The organic layer was further fractionated with n-hexane, 85% aqueous methanol (85% aq.MeOH) and the aqueous layer was separated into n-butanol and water, successively. Of the fractions, 85% aq.MeOH fraction showed the highest inhibitory activity of MMP-2 and MMP-9 in gelatin zymography and MMP ELISA kit. Furthermore, 85% aq.MeOH fraction most significantly suppressed cell migration. In RT-PCR and Western blot assay, n-butanol and 85% aq.MeOH fractions exerted the greatest inhibition on mRNA and protein expression of MMP-2 and MMP-9, respectively. As a result, C. pumila can be used as a good anti-invasive agent source.