• Development and Reproduction
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• v.12 no.2
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• pp.159-168
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• 2008

Nanog is a newly identified member of the homeobox family of DNA binding transcription factors that functions to maintain the undifferentiated state of stem cells. However, molecular mechanisms underlying the function of Nanog remain largely unknown. To elucidate the regulatory roles of Nanog involved in maintenance of P19 embryonal carcinoma (EC) stem cells, we transfected three small interfering RNA (siRNA) duplexes targeted against different regions of the Nanog gene into P19 cells. The Nanog siRNA-100 duplexes effectively decreased the expression of Nanog up to 30.7% compared to other two Nanog siRNAs, the Nanog siRNA-400 (67.9 %) and -793 (53.0%). When examined by RT-PCR and real-time PCR, the expression of markers for pluripotency such as Fgf4, Oct3/4, Rex1, Sox1 and Yes was downregulated at 48 h after transfection with Nanog siRNA-100. Furthermore, expression of the ectodermal markers, Fgf5 and Isl1 was reduced by Nanog knockdown. By contrast, the expression of other markers for pluripotency such as Cripto, Sox2 and Zfp57 was not affected by Nanog knockdown at this time. On the other hand, the expression of Lif/Stat3 pathway molecules and of the endoderm markers including Dab2, Gata4, Gata6 and the germ cell nuclear factor was not changed by Nanog knockdown. The results of this study demonstrated that the knockdown of Nanog expression by RNA interference in P19 cells was sufficient to modulate the expression of pluripotent markers involved in the self-renewal of EC stem cells. These results provide the valuable information on potential downstream targets of Nanog and add to our understanding of the function of Nanog in P19 EC stem cells.

• Journal of Internet Computing and Services
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• v.6 no.1
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• pp.85-93
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• 2005

This paper describes how to distribute high multi-dimensional facial expression data of vast quantity over a suitable space and produce facial expression animations by selecting expressions while animator navigates this space in real-time. We have constructed facial spaces by using about 2400 facial expression frames on this paper. These facial spaces are created by calculating of the shortest distance between two random expressions. The distance between two points In the space of expression, which is manifold space, is described approximately as following; When the linear distance of them is shorter than a decided value, if the two expressions are adjacent after defining the expression state vector of facial status using distance matrix expressing distance between two markers, this will be considered as the shortest distance (manifold distance) of the two expressions. Once the distance of those adjacent expressions was decided, We have taken a Floyd algorithm connecting these adjacent distances to yield the shortest distance of the two expressions. We have used CCA(Curvilinear Component Analysis) technique to visualize multi-dimensional spaces, the form of expressing space, into two dimensions. While the animators navigate this two dimensional spaces, they produce a facial animation by using user interface in real-time.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6315-6319
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• 2013

To study the differentiated expression of the proto-oncogene Pokemon in nasopharyngeal carcinoma (NPC) cell lines and tissues, mRNA and protein expression levels of CNE1, CNE2, CNE3 and C666-1 were detected separately by reverse transcription polymerase chain reaction (RT-PCR), real-time PCR and Western-blotting. The immortalized nasopharyngeal epithelial cell line NP69 was used as a control. The Pokemon protein expression level in biopsy specimens from chronic rhinitis patients and undifferentiated non keratinizing NPC patients was determined by Western-blotting and arranged from high to low: C666-1>CNE1>CNE2> CNE3>NP69. The Pokemon mRNA expression level was also arranged from high to low: CNE1>CNE2>NP69>C666-1>CNE3. Pokemon expression of NP69 and C666-1 obviously varied from mRNA to protein. The Pokemon protein level of NPC biopsy specimens was obviously higher than in chronic rhinitis. The data suggest that high Pokemon protein expression is closely associated with undifferentiated non-keratinizing NPC and may provide useful information for NPC molecular target therapy.

• YAKHAK HOEJI
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• v.44 no.4
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• pp.300-307
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• 2000

Expression of xenobiotic-metabolizing enzymes can be altered by xenobiotics, which represents changes in the production of reactive metabolic intermediates as well as toxicities in tissues. Metabolic intermediates derived from xenobiotics are considered to produce the reactive oxygen species including drug free radicals and hydroxyl free radicals, which would be ultimately responsible for drug-induced toxicities. The effects of 1,2-benzothiazine anti-inflammatory agents on the expression of xenobiotic-metabolizing enzymes including major cytochrome P450s, microsomal epoxide hydrolase (mEH) and glutathione S-transferase (GST) were studied in the liver with the aim of providing the part of information on potential production of reactive metabolites and hepatotoxicity by the agents. The synthetic compounds 24, 36 and 39 exhibited anti-inflammatory effects in rats as assessed by the Randall-Selitto method. The anti-inflammatory effect was detected as early as at 30 min after gavaging the agents with the ED5O being noted at 80 mg/kg, which was comparable to that of ibuprofen. Treatment of rats with each compound (100 mg/kg, 3d) resulted in no significant induction in the immunochemically-detectable cytochromes P45O 1A1/2, P450 2B1/2, P45O 2 Cl1 and P45O 2El. Changes in the mEN expression were also minimal, as evidenced by both Western blot and Northern blot analyses. Hepatic GST expression was slightly increased by the agents: GST Ya protein and mRNA expression was ～1.5-fold increased after treatment with compounds 24 and 39, whereas GST Yb1/2 and Yc1/2 mRNA levels were elevated 2- to 3-fold. In summary the effects of the synthetic 1,2-benzothiazines on the expression of major P45O, mEH and G57 were not significant, providing evidence that metabolic activation of the agents, potential drug interaction and hepatotoxicity would be minimal.

• Journal of Microbiology and Biotechnology
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• v.22 no.2
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• pp.190-198
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• 2012

RNA interference (RNAi) is rapidly becoming a valuable tool in biological studies, as it allows the selective and transient knockdown of protein expression. The short-interfering RNAs (siRNAs) transiently silence gene expression. By contrast, the expressed short-hairpin RNAs induce long-term, stable knockdown of their target gene. Trichoplusia ni (T. ni) cells are widely used for mammalian cell-derived glycoprotein expression using the baculovirus system. However, a suitable shRNA expression system has not been developed yet. We investigated the potency of shRNA-mediated gene expression inhibition using human and Drosophila U6 promoters in T. ni cells. Luciferase, EGFP, and ${\beta}$-N-acetylglucosaminidase (GlcNAcase) were employed as targets to investigate knockdown of specific genes in T. ni cells. Introduction of the shRNA expression vector under the control of human U6 or Drosophila U6 promoter into T. ni cells exhibited the reduced level of luciferase, EGFP, and ${\beta}$-N-acetylglucosaminidase compared with that of untransfected cells. The shRNA was expressed and processed to siRNA in our vector-transfected T. ni cells. GlcNAcase mRNA levels were down-regulated in T. ni cells transfected with shRNA vectors-targeted GlcNAcase as compared with the control vector-treated cells. It implied that our shRNA expression vectors using human and Drosophila U6 promoters were applied in T. ni cells for the specific gene knockdown.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.41 no.3
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• pp.83-92
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• 2004

Gene expression profile is numerical data of gene expression level from organism measured on the microarray. Generally, each specific tissue indicates different expression levels in related genes, so that we can classify cancer with gene expression profile. Because not all the genes are related to classification, it is needed to select related genes that is called feature selection. This paper proposes a new gene selection method using forward selection method in regression analysis. This method reduces redundant information in the selected genes to have more efficient classification. We used k-nearest neighbor as a classifier and tested with colon cancer dataset. The results are compared with Pearson's coefficient and Spearman's coefficient methods and the proposed method showed better performance. It showed 90.3% accuracy in classification. The method also successfully applied to lymphoma cancer dataset.

• BMB Reports
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• v.39 no.4
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• pp.441-447
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• 2006

Abuse of drugs can elicit compulsive drug seeking behaviors upon repeated administration, and ultimately leads to the phenomenon of addiction. We developed a procedure for the standardization of microarray gene expression data of rat brain in drug addiction and stored them in a single integrated database system, focusing on more effective data processing and interpretation. Another characteristic of the present database is that it has a systematic flexibility for statistical analysis and linking with other databases. Basically, we adopt an intelligent SQL querying system, as the foundation of our DB, in order to set up an interactive module which can automatically read the raw gene expression data in the standardized format. We maximize the usability of this DB, helping users study significant gene expression and identify biological function of the genes through integrated up-to-date gene information such as GO annotation and metabolic pathway. For collecting the latest information of selected gene from the database, we also set up the local BLAST search engine and non-redundant sequence database updated by NCBI server on a daily basis. We find that the present database is a useful query interface and data-mining tool, specifically for finding out the genes related to drug addiction. We apply this system to the identification and characterization of methamphetamine-induced genes' behavior in rat brain.

• Journal of Microbiology and Biotechnology
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• v.26 no.10
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• pp.1701-1707
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• 2016

Lipoxygenase (LOX) is an industrial enzyme with wide applications in food and pharmaceutical industries. The available structure information indicates that eukaryotic LOXs consist of N terminus β-barrel and C terminus catalytic domains. However, the latest crystal structure of Pseudomonas aeruginosa LOX shows it is significantly different from those of eukaryotic LOXs, including the N-terminal helix domain. In this paper, the functions of this N-terminal helix domain in the soluble expression and catalysis of P. aeruginosa LOX were analyzed. Genetic truncation of this helix domain resulted in an insoluble P. aeruginosa LOX mutant. The active C-terminal domain was obtained by dispase digestion of the P. aeruginosa LOX derivative containing the genetically introduced dispase recognition sites. This functional C-terminal domain showed raised substrate affinity but reduced catalytic activity and thermostability. Crystal structure analyses demonstrate that the broken polar contacts connecting the two domains and the exposed hydrophobic substrate binding pocket may contribute to the insoluble expression of the C terminus domain and the changes in the enzyme properties. Our data suggest that the N terminus domain of P. aeruginosa LOX is required for its soluble expression in E. coli, which is different from that of the eukaryotic LOXs. Besides this, this N-terminal domain is not necessary for catalysis but shows positive effects on the enzyme properties. The results presented here provide new and valuable information on the functions of the N terminus helix domain of P. aeruginosa LOX and further improvement of its enzyme properties by molecular modification.

• The Journal of the Korea Contents Association
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• v.7 no.4
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• pp.250-258
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• 2007

Typography is the combination of language of formative art. It is indeed the core means of human communication through understanding of language and formative values. Studies began on introduction of various techniques to overcome the phenomenon of the 'reaction of language', which appears as an impediment in delivery and sharing of information as the most fundamental roles. Successively, mobile printing types more readable and effective in delivering of meanings have been developed, thus widely distributed for general use. However, although such printing types might be easily used in image and digital media, such as in computer monitors, screens and mobile phone LCDs, etc., it is in fact difficult to use these printing types in printed surfaces, the traditional medium of information delivery, or in sign systems frequently encountered in our surrounding environment. As a solution for this, it is intended to create an effect of communication closer to dynamic typography expression by approaching visual message delivery system from the essence and substance of the color application, which corresponds to the visual spatial expression effect, the core element of expression in dynamic typography to possess significantly more powerful effect in terms of both message delivery capacity and readability than the conventional means of static typography.

• Korean journal of communication and information
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• v.54
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• pp.32-57
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• 2011

This study examined how the Korean courts have made a balance between rights of school teachers' expression and the public interests derived from regulating their rights for expression in related cases. Under the Korean laws such as National Public Service Law and the Law on Assembly and Demonstration, school teachers are considered as civil servants and basically not allowed to assemble to demonstrate for their own interests. The analysis revealed that in 24 cases from a total of 31 teacher-related court cases, teachers were found guilty in violation of related laws. In deciding whether the teachers' participation on anti-government assembly was guilty or not, the courts put an emphasis on public purpose of their expression, the degree to which their expressions affect the society, and specific contents of their expression. Conclusively, it was found out that in applying the related law, Korean courts tend to overweigh the public interests, rather than the teachers' right to express.