• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2006.06a
• /
• pp.410-411
• /
• 2006

High throughput analysis using a DNA chip microarray is powerful tool in the post genome era. Less labor-intensive and lower cost-performance is required. Thus, this paper aims to develop the multi-channel type label-free DNA chip and detect SNP (Single nucleotide polymorphisms). At first, we fabricated a high integrated type DNA chip array by lithography technology. Various probe DNAs were immobilized on the microelectrode array. We succeeded to discriminate of DNA hybridization between target DNA and mismatched DNA on microarray after immobilization of a various probe DNA and hybridization of label-free target DNA on. the electrodes simultaneously. This method is based on redox of an electrochemical ligand.

• Proceedings of the Korean Society of Toxicology Conference
• /
• 2002.11b
• /
• pp.204-204
• /
• 2002

Alcohol drinking during pregnancy can result in abnormal fetal development including fetal alcohol syndrome (FAS). The molecular mechanisms of FAS, however, is not completely elucidated. In the present study, we evaluated the developmental toxicity of ethanol and its metabolite, acetaldehyde using post implantation whole embryo culture and determined changes of gene expression by ethanol treatment by cDNA microarray.(omitted)

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2004.07b
• /
• pp.845-848
• /
• 2004

High throughput analysis using a DNA chip microarray is powerful tool in the post genome era. Less labor-intensive and lower cost-performance is required. Thus, this paper aims to develop the multi-channel type label-free DNA chip and detect SNP (Single nucleotide polymorphisms). At first, we fabricated a high integrated type DNA chip array by lithography technology. Various probe DNAs were immobilized on the microelectrode array. We succeeded to discriminate of DNA hybridization between target DNA and mismatched DNA on microarray after immobilization of a various probe DNA and hybridization of label-free target DNA on the electrodes simultaneously. This method is based on redox of an electrochemical ligand.

• Journal of the korean academy of Pediatric Dentistry
• /
• v.37 no.3
• /
• pp.275-287
• /
• 2010

Deep caries may induce pulpitis and the pulpal tissue interacts with microbial invasion. The immune response to protect the pulpal tissue can be mediated by cellular signal molecules produced by the pulpal cells. The understanding of these processes is important to find future therapeutic method for the diseased pulp. The pulp tissue from sound teeth was set as control group (n=30) and the pulp tissue from decayed teeth was set as test group (n=30). Total RNA was extracted from the pulp of each group and it was used for cDNA microarray and reverse transcriptase-polymerase chain reaction(RT-PCR). The expression of TGF-${\beta}1$ was studied by immunohistochemistry. The results were as follows: 1. cDNA microarray analysis identified 520 genes with 6-fold or greater difference in expression level with 143 genes more abundant in health and 377 genes more abundant in disease. 2. The RT-PCR analysis was done for randomly selected 14 genes and the results supported the result of cDNA microarray assay. 3. TGF-${\beta}1$ was highly expressed in the carious pulp and it was found in odontoblast by immunohistochemistry. In conclusion, many cytokines were found to be significantly changed their expression in the diseased pulp(/M/>1.6).

• Journal of Pharmacopuncture
• /
• v.9 no.2
• /
• pp.5-16
• /
• 2006

Objective : It has long been known about the osteogenic effect of CPC-HAS on bone tissues. However, it has not been determined the effect of CPC-HAS on cancer cells. The purpose of this study is to screen the CPC-HAS mediated differentially expressed genes in cancer cells such as HepG2 hepatoma cells. Oligonucleotide microarray and proteomics approaches were employed to screen the differential expression genes. Methods : CPC-HAS was prepared by boiling and stored at $-70^{\circ}C$ until use. Cells were treated with various concentrations of CPC-HAS (0.1, 0.5, 1.5, 10, 20mg/ml) for 24 h. Cell toxicity was tested by MTT assay. To screen the differentially expressed genes in cancer cells, cells were treated with 1.5mg/ml of CPC-HAS. For oligonucleotide microarray assay, total RNA was used for gene expression analysis using oligonucleotide Genechip(Human genome Ul33 Plus 2.0., Affimatrix Co.). For proteomic analysis, total protein was analyzed by 2D gel electrophoresis and Q-TOF mass spectrometer. Results : It has no cytotoxic effects on both HepG2 cell in all concentrations(0.l, 0.5, 1.5, 10, 20mg/ml). In oligonucleotide microarray assay, the number of more than twofold differentially regulated known genes was 23 with 5 up-regulated and 18 down-regulated genes in HepG2 cells. In proteomic analysis, three spots were identified by 2D-gel electrophoresis and Q-TOF analysis. Two down-regulated proteins were aldehyde dehydrogenase 1 and enolase 1, and up-regulated protein was fatty acid binding protein 1 by 1.5mg/ml of CPC-HAS. Discussion : This study showed the screening of CPC-HAS mediated differentially regulated genes using combined approaches of oligonucleotide microarray and proteomic analysis. The screened genes will be used for the better understanding of the therapeutic effects of CPC-HAS on cancer fields.

• Proceedings of the Korean Society of Developmental Biology Conference
• /
• 2005.10a
• /
• pp.109-109
• /
• 2005

• Proceedings of the Korean Society of Embryo Transfer Conference
• /
• 2005.10a
• /
• pp.109-109
• /
• 2005

• The Korean Journal of Applied Statistics
• /
• v.24 no.6
• /
• pp.1103-1113
• /
• 2011

Gene expression data is obtained through many stages of an experiment and errors produced during the process may cause missing values. Due to the distinctness of the data so called 'small n large p', genes have to be selected for statistical analysis, like classification analysis. For this reason, imputation and gene selection are important in a microarray data analysis. In the literature, imputation, gene selection and classification analysis have been studied respectively. However, imputation, gene selection and classification analysis are sequential processing. For this aspect, we compare the performance of classification methods after imputation and gene selection methods are applied to microarray data. Numerical simulations are carried out to evaluate the classification methods that use various combinations of the imputation and gene selection methods.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.9
• /
• pp.4793-4799
• /
• 2012

Hypoxia is commonly featured during glioma growth and plays an important role in the processes underlying tumor progression to increasing malignancy. Here we compared the gene expression profiles of rat C6 malignant glioma cells under normoxic and hypoxic conditions by cDNA microarray analysis. Compared to normoxic culture conditions, 180 genes were up-regulated and 67 genes were down-regulated under hypoxia mimicked by $CoCl_2$ treatment. These differentially expressed genes were involved in mutiple biological functions including development and differentiation, immune and stress response, metabolic process, and cellular physiological response. It was found that hypoxia significantly regulated genes involved in regulation of glycolysis and cell differentiation, as well as intracellular signalling pathways related to Notch and focal adhesion, which are closely associated with tumor malignant growth. These results should facilitate investigation of the role of hypoxia in the glioma development and exploration of therapeutic targets for inhibition of glioma growth.

• Journal of Genetic Medicine
• /
• v.16 no.2
• /
• pp.76-80
• /
• 2019

About 15% to 20% of all clinically recognized pregnancies result in spontaneous abortion or miscarriage, and chromosomal anomalies can be identified in up to 50% of first trimester miscarriages. Chromosomal microarray analysis (CMA) is currently considered first-tier testing for detecting fetal chromosomal abnormalities and is supported by the absence of cell culture failure or erroneous results due to cell contamination in pregnancy loss. Triploidy is a lethal chromosome number abnormality characterized by an extra haploid set of chromosomes. Triploidy is one of the most common chromosomal aberrations in first trimester spontaneous abortions. Here, we report two cases of triploidy abortion that were not detected using array comparative genomic hybridization-based CMA. The aim of this report was to remind clinicians of the limitations of chromosomal testing and the misdiagnosis that can result from biased test selection.