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EFFECT OF THE NUCLEAR FACTOR I-C ON THE FORMATION OF HERTWIG'S EPITHELIAL ROOT SHEATH DURING ROOT DEVELOPMENT (Nuclear factor I-C가 치근발생 과정에서 Hertwig's 상피초 형성에 미치는 영향)

  • Shin, In-Cheol;Park, Joo-Cheol;Jeong, Moon-Jin;Oh, Hyun-Ju;Park, Sun-Hwa;Lee, Chang-Seop;Kim, Heung-Joong
    • Journal of the korean academy of Pediatric Dentistry
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    • v.32 no.3
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    • pp.576-583
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    • 2005
  • Tooth formation is a complex developmental process that is mediated through a series of reciprocal epithelial-mesenchymal interactions. Several signal pathways and transcription factors have been implicated in regulating molar crown development, but relatively little is known about the regulation of root development. It was reported that NFI-C knockout mice showed abnormal root formation with normal crown. The aims of this study are to elucidate how the NFI-C regulate the determine of root shape and odontoblasts differentiation. We carried out immunohistochemistry using cytokeratin to investigate the role of Hertwig's epithelial root sheath and DSPP mRNA in-situ hybridization to conform the nature of root dentin during root development in NFI-C knockout mice. Cytokeratin reacted with all the HERS cells and the continuity of cytokeratin positive cells between the HERS cells and enamel epithelium was lost in the cervical region both wild and K/O types. After root dentin deposition cytokeratin positive-HERS cells showed irregularity and loss of polarity in the cervical region in K/O type. DSPP mRNA was strongly expressed in odontoblasts of crown and root dentin in wild type mice, whereas expression of DSPP mRNA was restricted in odontoblast of crown dentin in the K/O type. During root formation in NFI-C knockout mice, HERS normally grow out of the crown but fail to induce odontoblast differentiation in root portion. These results suggest that NFI-C may play important roles in odontoblast differentiation during root dentin formation.

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Characterization and Functional Analysis of Obox4 during Oocyte Maturation by RNA Interference (생쥐의 난소와 난자에서의 Obox4의 동정과 RNAi를 이용한 기능연구)

  • Lee, Hyun-Seo;Lee, Kyung-Ah
    • Clinical and Experimental Reproductive Medicine
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    • v.34 no.4
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    • pp.293-303
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    • 2007
  • Objective: Previously, we identified differentially expressed genes between GV and MII stage mouse oocytes using ACP technology. When we study one of GV selective genes, Obox family, we found Obox4 mRNA expression in ovaries that has been reported as expressed exclusively in testis. Therefore, this study was conducted for characterization and functional analysis for Obox4. Methods: Expression of Obox4 mRNA was examined in gonads and oocytes by RT-PCR. To determine the role of Obox4 in oocyte maturation, Obox4 dsRNA was microinjected into the cytoplasm of GV oocytes followed by 16 h of incubation in the plain medium or by 24 h of incubation in the medium containing IBMX. After RNAi, phenotypes and maturation rates were observed, change in mRNA expression was evaluated, and chromosomal status was confirmed by orcein staining. Results: Obox4 has minimal expression in the ovary compared to that of the other family members. When oocytes were cultured for 16 h in M16 medium after RNAi, maturation rate was not changed significantly, compared with that of non-injected or buffer-injected control oocytes. Surprisingly, however, when oocytes were cultured for 24 h in M16 containing IBMX, in which oocytes were supposed to arrest at GV stage, Obox4 RNAi oocytes were advanced to MI and MII. Spindle structure was disappeared and the chromosomes were condensed in the oocytes after Obox4 RNAi. Conclusions: This is the first report on the expression of Obox4 in the ovary and oocytes. Results of the study suggest that Obox4 plays a crucial role in spindle formation and chromosome segregation during meiosis in oocytes. In addition, Obox4 may play an important role in cAMP-dependent signal cascades of GV-arrest in mouse oocytes.

A Study on the DC Resistivity Method to Image the Underground Structure Beneath River or Lake Bottom (하저 지반특성 규명을 위한 수상 전기비저항 탐사에 관한 연구)

  • Kim Jung-Ho;Yi Myeong-Jong;Song Yoonho;Choi Seong-Jun;Lee Seoung Kon;Son Jeong-Sul;Chung Seung-Hwan
    • Geophysics and Geophysical Exploration
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    • v.5 no.4
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    • pp.223-235
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    • 2002
  • Since weak Bones or geological lineaments are likely to be eroded, there may develop weak Bones beneath rivers, and a careful evaluation of ground condition is important to construct structures passing through a river. DC resistivity method, however, has seldomly applied to the investigation of water-covered area, possibly because of difficulties in data aquisition and interpretation. The data aquisition having high quality may be the most important factor, and is more difficult than that in land survey, due to the water layer overlying the underground structure to be imaged. Through the numerical modeling and the analysis of a case history, we studied the method of resistivity survey at the water-covered area, starting from the characteristics of measured data, via data acquisition method, to the interpretation method. We unfolded our discussion according to the installed locations of electrodes, ie., floating them on the water surface, and installing them at the water bottom, because the methods of data acquisition and interpretation vary depending on the electrode location. Through this study, we could confirm that the DC resistivity method can provide fairly reasonable subsurface images. It was also shown that installing electrodes at the water bottom can give the subsurface image with much higher resolution than floating them on the water surface. Since the data acquired at the water-covered area have much lower sensitivity to the underground structure than those at the land, and can be contaminated by the higher noise, such as streaming potential, it would be very important to select the acquisition method and electrode array being able to provide the higher signal-to-noise ratio (S/N ratio) data as well as the high resolving power. Some of the modified electrode arrays can provide the data having reasonably high S/N ratio and need not to install remote electrode(s), and thus, they may be suitable to the resistivity survey at the water-covered area.

Derivation of rock parameters from Televiewer data (텔레뷰어에 의한 토목설계 매개변수의 산출)

  • Kim Jung-Yul;Kim Yoo-Sung
    • 한국지구물리탐사학회:학술대회논문집
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    • 1999.08a
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    • pp.137-155
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    • 1999
  • Recently, Televiewer(Borehole Acoustic Scanner(Televiewer)) has come to be widely used specially for the general engineering construction design. The Televiewer tool using a focussed acoustic beam is to detect the amplitude and traveltime of each reflected acoustic signal at the wall, resulting in the amplitude- and traveltime image respectively. Fractures can be well detected, because they easily scatter the acoustic energy due to the highly narrow beam. In addition, the drilling work will rough the borehole wall so that the acoustic energy can be scattered simply due to the roughness of the wall. Thus, the amplitude level can be directed associated with the elastic properties(impedance) and the hardness of the rock as well. Meanwhile, the traveltime image provides an information about the borehole shape and can be converted to a high precision 3D caliper log(max. 288 arms). In this paper, based on the high resolution of Televiewer images, general evaluation methods are illustrated to derive very reliable rock parameters.

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Processed Panax ginseng, sun ginseng, inhibits the differentiation and proliferation of 3T3-L1 preadipocytes and fat accumulation in Caenorhabditis elegans

  • Lee, Hyejin;Kim, Jinhee;Park, Jun Yeon;Kang, Ki Sung;Park, Joeng Hill;Hwang, Gwi Seo
    • Journal of Ginseng Research
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    • v.41 no.3
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    • pp.257-267
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    • 2017
  • Background: Heat-processed ginseng, sun ginseng (SG), has been reported to have improved therapeutic properties compared with raw forms, such as increased antidiabetic, anti-inflammatory, and antihyperglycemic effects. The aim of this study was to investigate the antiobesity effects of SG through the suppression of cell differentiation and proliferation of mouse 3T3-L1 preadipocyte cells and the lipid accumulation in Caenorhabditis elegans. Methods: To investigate the effect of SG on adipocyte differentiation, levels of stained intracellular lipid droplets were quantified by measuring the oil red O signal in the lipid extracts of cells on differentiation Day 7. To study the effect of SG on fat accumulation in C. elegans, L4 stage worms were cultured on an Escherichia coli OP50 diet supplemented with $10{\mu}g/mL$ of SG, followed by Nile red staining. To determine the effect of SG on gene expression of lipid and glucose metabolism-regulation molecules, messenger RNA (mRNA) levels of genes were analyzed by real-time reverse transcription-polymerase chain reaction analysis. In addition, the phosphorylation of Akt was examined by Western blotting. Results: SG suppressed the differentiation of 3T3-L1 cells stimulated by a mixture of 3-isobutyl-1-methylxanthine, dexamethasone, and insulin (MDI), and inhibited the proliferation of adipocytes during differentiation. Treatment of C. elegans with SG showed reductions in lipid accumulation by Nile red staining, thus directly demonstrating an antiobesity effect for SG. Furthermore, SG treatment down-regulated mRNA and protein expression levels of peroxisome proliferator-activated receptor subtype ${\gamma}$ ($PPAR{\gamma}$) and CCAAT/enhancer-binding protein-alpha ($C/EBP{\alpha}$) and decreased the mRNA level of sterol regulatory element-binding protein 1c in MDI-treated adipocytes in a dose-dependent manner. In differentiated 3T3-L1 cells, mRNA expression levels of lipid metabolism-regulating factors, such as amplifying mouse fatty acid-binding protein 2, leptin, lipoprotein lipase, fatty acid transporter protein 1, fatty acid synthase, and 3-hydroxy-3-methylglutaryl coenzyme A reductase, were increased, whereas that of the lipolytic enzyme carnitine palmitoyltransferase-1 was decreased. Our data demonstrate that SG inversely regulated the expression of these genes in differentiated adipocytes. SG induced increases in the mRNA expression of glycolytic enzymes such as glucokinase and pyruvate kinase, and a decrease in the mRNA level of the glycogenic enzyme phosphoenol pyruvate carboxylase. In addition, mRNA levels of the glucose transporters GLUT1, GLUT4, and insulin receptor substrate-1 were elevated by MDI stimulation, whereas SG dose-dependently inhibited the expression of these genes in differentiated adipocytes. SG also inhibited the phosphorylation of Akt (Ser473) at an early phase of MDI stimulation. Intracellular nitric oxide (NO) production and endothelial nitric oxide synthase mRNA levels were markedly decreased by MDI stimulation and recovered by SG treatment of adipocytes. Conclusion: Our results suggest that SG effectively inhibits adipocyte proliferation and differentiation through the downregulation of $PPAR{\gamma}$ and $C/EBP{\alpha}$, by suppressing Akt (Ser473) phosphorylation and enhancing NO production. These results provide strong evidence to support the development of SG for antiobesity treatment.

Availability Assessment of Single Frequency Multi-GNSS Real Time Positioning with the RTCM-State Space Representation Parameters (RTCM-SSR 보정요소 기반 1주파 Multi-GNSS 실시간 측위의 효용성 평가)

  • Lee, Yong-Chang;Oh, Seong-Jong
    • Journal of Cadastre & Land InformatiX
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    • v.50 no.1
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    • pp.107-123
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    • 2020
  • With stabilization of the recent multi-GNSS infrastructure, and as multi-GNSS has been proven to be effective in improving the accuracy of the positioning performance in various industrial sectors. In this study, in view that SF(Single frequency) GNSS receivers are widely used due to the low costs, evaluate effectiveness of SF Real Time Point Positioning(SF-RT-PP) based on four multi-GNSS surveying methods with RTCM-SSR correction streams in static and kinematic modes, and also derive response challenges. Results of applying SSR correction streams, CNES presented good results compared to other SSR streams in 2D coordinate. Looking at the results of the SF-RT-PP surveying using SF signals from multi-GNSS, were able to identify the common cause of large deviations in the altitude components, as well as confirm the importance of signal bias correction according to combinations of different types of satellite signals and ionospheric delay compensation algorithm using undifferenced and uncombined observations. In addition, confirmed that the improvement of the infrastructure of Multi-GNSS allows SF-RT-SPP surveying with only one of the four GNSS satellites. In particular, in the case of code-based SF-RT-SPP measurements using SF signals from GPS satellites only, the difference in the application effect between broadcast ephemeris and SSR correction for satellite orbits/clocks was small, but in the case of ionospheric delay compensation, the use of SBAS correction information provided more than twice the accuracy compared to result of the Klobuchar model. With GPS and GLONASS, both the BDS and GALILEO constellations will be fully deployed in the end of 2020, and the greater benefits from the multi-GNSS integration can be expected. Specially, If RT-ionospheric correction services reflecting regional characteristics and SSR correction information reflecting atmospheric characteristics are carried out in real-time, expected that the utilization of SF-RT-PPP survey technology by multi-GNSS and various demands will be created in various industrial sectors.

The Extract from Artemisia annua Linné. Induces p53-independent Apoptosis through Mitochondrial Signaling Pathway in A549 Lung Cancer Cells (A549 폐암세포에서 미토콘드리아 경로를 통한 개똥쑥 추출물의 apoptosis 유도 효과)

  • Kim, Bo-Min;Kim, Guen-Tae;Kim, Eun-Ji;Lim, Eun-Gyeong;Kim, Sang-Yong;Kim, Young-Min
    • Journal of Life Science
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    • v.26 no.8
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    • pp.887-894
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    • 2016
  • The extract from Artemisia annuain L.(AAE) is known as a medicinal herb that is effective against cancer. Apoptosis is the process of programmed cell death, and mitochondria are known to play a central role in cell death control. In this study, we evaluated the p53-independent apoptosis of extract of AAE through downregulation of Bcl-2 and the mitochondrial pathway in A549 (lung cancer cells). AAE may exert cancer cell apoptosis through regulating p-Akt, Cox-2, p53 and mitochondria-mediated apoptotic proteins. p-Akt/cox-2 is known to play an important role in cell proliferation and cell survival. The Bcl-2 pro-apoptotic proteins (such as Bax, Bak and Bim) mediate the permeabilization of the mitochondrial outer membrane. Treatment of AAE reduces p-Akt, p-Mdm2, cox-2 and anti-apoptotic proteins (such as Bcl-2), while tumor suppressor p53 and pro-apoptotic proteins. Activation of Bax/Bak releases cytochrome c from mitochondria to the cytosol to activate a caspase. Caspase-3 is the major effector caspase associated with apoptotic pathways. Caspase-3 generally exists in cytoplasm in the form of a pro-enzyme. In the initiation stage of apoptosis, caspase-3 is activated by proteolytic cleavage and activated caspase-3 cleaves poly (ADP-ribose) polymerase (PARP). We treated Pifithrin-α (p53 inhibitor) and Celecoxib (Cox-2 inhibitor) to learn the relationship between the signal transduction of proteins associated with apoptosis. These results suggest that AAE induces apoptosis through a p53-independent pathway in A549.

LP-M, a Novel Butanol-Extracts Isolated from Liriope platyphylla, could Induce the Neuronal Cell Survival and Neuritic Outgrowth in Hippocampus of Mice through Akt/ERK Activation on NGF Signal Pathway (맥문동(Liriope platyphylla)의 새로운 부탄올 추출물인 LP-M이 Akt/ERK NGF receptor signaling pathway를 통해 뇌조직에서 신경세포의 생존과 성장에 미치는 영향에 관한 연구)

  • Nam, So-He;Choi, Sun-Il;Goo, Jun-Seo;Kim, Ji-Eun;Lee, Yoen-Kyung;Hwang, In-Sik;Lee, Hye-Ryun;Lee, Young-Ju;Lee, Hong-Gu;Choi, Young-Whan;Hwang, Dae-Youn
    • Journal of Life Science
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    • v.21 no.9
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    • pp.1234-1243
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    • 2011
  • Liriope platyphylla has been used in oriental medicine as an effective medical plant to improve symptoms of cough, sputum production, neurodegenerative disorders, obesity and diabetes for long time. In order to investigate the effects of novel extracts on nerve growth factors (NGF)-stimulated neuritic outgrowth, the alteration of NGF expression and NGF receptor signaling pathway were detected in neuroblastoma cells and C57BL/6 mice. Of a total of 13 novel extracts, 4 extracts (LP-E, LP-M, LP-M50, LP2E17PJ) showed high viability on MTT assay. Also, all of these extracts induced NGF secretion and NGF mRNA expression in neuroblastoma cells. However, the NGF-induced neuritic outgrowth from PC12 cells was only stimulated by LP-E, LP-M and LP-M50. Furthermore, we selected LP-M as a best candidate, based on method and amounts of extraction, in order to verify its effect in mice. C57BL/6 mice were treated with 50 mg/kg of LP-M for 2 weeks and the effects on NGF regulation were analyzed with various methods. The expression of NGF mRNA was significantly increased in LP-M treated mice compared to vehicle treated mice. Also, the signaling pathway of p75NTR was inhibited in the cortex by LP-M treatment, with no change in the hippocampus of brain. However, the signaling pathway of TrkA was dramatically activated in only hippocampus via LP-M treatment. Therefore, these results suggest that the novel four extracts of L. platyphylla may contribute to the regulation of NGF expression and secretion in neuronal cells. LP-M was especially considered to be an excellent candidate for a neurodegenerative disease-therapeutic drug.

Role of PKR and EGR-1 in Induction of Interleukin-S by Type B Trichothecene Mycotoxin Deoxynivalenol in the Human Intestinal Epithelial Cells (B형 트리코테센 곰팡이 독소 데옥시니발레놀에 의한 인체 장관 상피세포 염증성 인터루킨 8유도에서의 PKR과 EGR-1의 상호 역할 규명)

  • Park, Seong-Hwan;Yang, Hyun;Choi, Hye-Jin;Park, Yeong-Min;Ahn, Soon-Cheol;Kim, Kwan-Hoi;Lee, Soo-Hyung;Ahn, Jung-Hoon;Chung, Duk-Hwa;Moon, Yu-Seok
    • Journal of Life Science
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    • v.19 no.7
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    • pp.949-955
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    • 2009
  • Mucosal epithelia sense external stress signals and transmit them to the intracellular cascade responses. Ribotoxic stress-producing chemicals such as deoxynivalenol (DON) or other trichothecene mycotoxins have been linked with gastrointestinal inflammatory diseases by Fusarium-contamination. The purpose of this study was to test the hypothesis that DON evokes the epithelial sentinel signals of RNA-dependent protein kinase (PKR) and early growth response gene 1 (EGR-1), which together contribute to the pro-inflammatory cytokine interleukin 8 (IL-8) in human intestinal epithelial cells. PKR suppression by the dominant negative PKR expression attenuated DON-stimulated interleukin-8 production. Moreover, 1L-8 transcriptional activation by DON was also reduced by PKR inhibition in the human intestinal epithelial cells. Treatment with the PKR inhibitor also suppressed EGR-1 promoter activity, mRNA and protein induction, although mitogen-activated protein (MAP) kinases such as extracellular signal-regulated protein kinases (ERK) 1/2, p38, c-Jun N-terminal Kinase (INK) were little affected or even enhanced in presence of a PKR inhibitor. These patterns were also compared in the EGR-1-suppressed cells, which showed much more suppressed production of 1L-8. All things taken into consideration, DON-activated sentinel signals of EGR-1 via PKR mediated interleukin-8 production in human intestinal epithelial cells, which provide insight into the possible general mechanism associated with mucosal inflammation as an intestinal toxic insult by ribotoxic trichothecene mycotoxins.

Vibrio Vulnificus Induces the Inflammation of Mouse Ileal Epithelium: Involvement of Protein Kinase C and Nuclear Factor-Kappa B (회장 상피세포에서 비브리오균(Vibrio vulnificus)의 염증 유도 기작 연구: protein kinase C와 nuclear factor kappa-B의 관련성)

  • Han, Gi Yeon;Jung, Young Hyun;Jang, Kyung Ku;Choi, Sang Ho;Lee, Sei-Jung
    • Journal of Life Science
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    • v.24 no.6
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    • pp.664-670
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    • 2014
  • In the present study, we investigate the role of V. vulnificus in promoting the inflammation of mouse ileal ephitelium and its related signaling pathways. ICR mice were infected orally with V. vulnificus ($1{\times}10^9CFU$) for 16 h as a representative model of food-borne infection. To find the major portal of entry of V. vulnificus in mouse intestine, we have measured the levels of bacterial colonization in small intestine, colon, spleen, and liver. V. vulnificus appeared to colonize in intestine and colon in the order of ileum >> jejunum> colon, but lack in the duodenum, spleen, and liver. V. vulnificus in ileum caused severe necrotizing enteritis and showed shortened villi heights accompanied by an expanded width and inflammation, compared with the control mice. V. vulnificus induced ileal epithelium inflammation by activating phosphorylation of PKC and membrane translocation of $PKC{\alpha}$. V. vulnificus induced the phosphorylation of ERK and JNK, but did not affect p38 MAPK phosphorylation. Notably, V. vulnificus stimulated the I-${\kappa}B$-dependent phosphorylation of NF-${\kappa}B$ in mouse ileal epithelium. Finally, the ileal infection of V. vulnificus resulted in a significant increase in expression of proinflammatory cytokines and Toll-like receptors, respectively, compared to the control. Collectively, our results indicate that V. vulnificus induces ileal epithelium inflammation by increasing NF-${\kappa}B$ phosphorylation via activation of PKC, ERK, and JNK, which is critical for host defense mechanism in food-borne infection by V. vulnificus.