1.Introduction of Radiolabeled Therapeutic Oligonucleotides As Nanonuclear Explosive Gene Therapy.
Jae Gol CHOE ; Hee Young LEE ; Gil Hong PARK ; Chong Kun RYU ; Meyoung Kon KIM
Korean Journal of Nuclear Medicine 2001;35(3):125-130
No abstract available.
Genetic Therapy*
;
Oligonucleotides*
2.Distrubution of gamma-Glutamyltransferase in Blood-Brain Barrier Pericytes Using Monoclonal Anti gamma-Glutamyltransferase Antibodies.
Byoung Kyu LEE ; Meyoung Kon KIM ; Kyu Man SHIN ; Chong Kun RYU
Journal of Korean Neurosurgical Society 1995;24(3):253-261
gamma-Glutamyltransferase(GGT: E.C. 2.3.2.2.) is a glycoprotein enzyme which is involved in glutathione metabolism and amino acid transport through the plasma membrane. It is distributed widely in several organs including liver, kidney, pancrease and brain. GGTs derived from the brain of Wister rats and BALB/c mice were biochemically purified to a specific activity of 4246.2, 862.1 units per mg of protein, a purification folds 93.7, 43.8 and the final yield 65.8, 44.0% respectively. Electrophoretic pattern of purified GGTs from rats and mice brain shows very similar protein fraction each other. We have produced six monoclonal antibodies(GGT-Mab 1-6) against 2-acetamidogluorene treated rat liver GGT. Using these GGT-Mab 1-6 we performed immunohistochemistry(IHC) to study the distribution of GGT isozymes in normal tissues of rat brain and in neoplastic tissues of human brain. The results indicated that human brain GGT was localized in pericytes of blood-brain barrier, especially in the blood-rich portion of the brain(e.g. cerebellum of rat, meningioma and craniopharyngioma of human). Therefore these Maps may be used to evaluate the distribution of GGT isozymes in different tissues.
Animals
;
Antibodies*
;
Antibodies, Monoclonal
;
Blood-Brain Barrier*
;
Brain
;
Cell Membrane
;
Cerebellum
;
Craniopharyngioma
;
gamma-Glutamyltransferase*
;
Glutathione
;
Glycoproteins
;
Humans
;
Isoenzymes
;
Kidney
;
Liver
;
Meningioma
;
Metabolism
;
Mice
;
Pancreas
;
Pancrelipase
;
Pericytes*
;
Rats
3.Gene Expression Profiles in Cervical Cancer with Radiation Therapy Alone and Chemo-radiation Therapy.
Kyu Chan LEE ; Meyoung kon KIM ; Jooyoung KIM ; You Jin HWANG ; Myung Sun CHOI ; Chul Yong KIM
The Journal of the Korean Society for Therapeutic Radiology and Oncology 2003;21(1):54-65
PURPOSE: To analyze the gene expression profiles of uterine cervical cancer, and its variation after radiation therapy, with or without concurrent chemotherapy, using a cDNA microarray. MATERIALS AND METHODS: Sixteen patients, 8 with squamous cell carcinomas of the uterine cervix, who were treated with radiation alone, and the other 8 treated with concurrent chemo-radiation, were included in the study. Before the starting of the treatment, tumor biopsies were carried out, and the second time biopsies were performed after a radiation dose of 16.2~27 Gy. Three normal cervix tissues were used as a control group. The microarray experiments were performed with 5 groups of the total RNAs extracted individually and then admixed as control, pre-radiation therapy alone, during-radiation therapy alone, pre-chemoradiation therapy, and during-chemoradiation therapy. The 33P-labeled cDNAs were synthesized from the total RNAs of each group, by reverse transcription, and then they were hybridized to the cDNA microarray membrane. The gene expression of each microarrays was captured by the intensity of each spot produced by the radioactive isotopes. The pixels per spot were counted with an Arrayguage(R), and were exported to Microsoft Excel(R). The data were normalized by the Z transformation, and the comparisons were performed on the Z-ratio values calculated. RESULTS: The expressions of 15 genes, including integrin linked kinase (ILK), CDC28 protein kinase 2, Spry 2, and ERK 3, were increased with the Z-ratio values of over 2.0 for the cervix cancer tissues compared to those for the normal controls. Those genes were involved in cell growth and proliferation, cell cycle control, or signal transduction. The expressions of the other 6 genes, including G protein coupled receptor kinase 6, were decreased with the Z-ratio values of below -2.0. After the radiation therapy, most of the genes, with a previously increase expressions, represented the decreased expression profiles, and the genes, with the Z-ratio values of over 2.0, were cyclic nucleotide gated channel and 3 Expressed sequence tags (EST). In the concurrent chemo-radiation group, the genes involved in cell growth and proliferation, cell cycle control, and signal transduction were shown to have increased expressions compared to the radiation therapy alone group. The expressions of genes involved in angiogenesis (angiopoietin-2), immune reactions (formyl peptide receptor-like 1), and DNA repair (cAMP phosphodiesterase) were increased, however, the expression of gene involved in apoptosis (death associated protein kinase) was decreased. CONCLUSION: The different kinds of genes involved in the development and progression of cervical cancer were identified with the cDNA microarray, and the proposed theory is that the proliferation signal starts with ILK, and is amplified with Spry 2 and MAPK signaling, and the cellular mitoses are increased with the increased expression of Cdc 2 and cell division kinases. After the radiation therapy, the expression profiles demonstrated the evidence of the decreased cancer cell proliferation. There was no significant difference in the morphological findings of cell death between the radiation therapy alone and the chemo-radiation groups in the second time biopsy specimen, however, the gene expression profiles were markedly different, and the mechanism at the molecular level needs further study.
Apoptosis
;
Biopsy
;
Carcinoma, Squamous Cell
;
Cell Death
;
Cell Division
;
Cell Proliferation
;
Centers for Disease Control and Prevention (U.S.)
;
Cervix Uteri
;
Cyclic Nucleotide-Gated Cation Channels
;
DNA Repair
;
DNA, Complementary
;
Drug Therapy
;
Expressed Sequence Tags
;
Female
;
Gene Expression*
;
GTP-Binding Proteins
;
Humans
;
Membranes
;
Mitosis
;
Oligonucleotide Array Sequence Analysis
;
Phosphotransferases
;
Protein Kinases
;
Radioisotopes
;
Reverse Transcription
;
RNA
;
Signal Transduction
;
Transcriptome*
;
Uterine Cervical Neoplasms*
4.Radioactive cDNA microarray in Neurospsychiatry.
Jae Gol CHOE ; Kyung Ho SHIN ; Min Soo LEE ; Meyoung kon KIM
Korean Journal of Nuclear Medicine 2003;37(1):43-52
Microarray technology allows the simultaneous analysis of gene expression patterns of thousands of genes, in a systematic fashion, under a similar set of experimental conditions, thus making the data highly comparable. In some cases arrays are used simply as a primary screen leading to downstream molecular characterization of individual gene candidates. In other cases, the goal of expression profiling is to begin to identify complex regulatory networks underlying developmental processes and disease states. Microarrays were originally used with cell lines or other simple model systems. More recently, microarrays have been used in the analysis of more complex biological tissues including neural systems and the brain. The application of cDNA arrays in neuropsychiatry has lagged behind other fields for a number of reasons. These include a requirement for a large amount of input probe RNA in fluorescent-glass based array systems and the cellular complexity introduced by multicellular brain and neural tissues. An additional factor that impacts the general use of microarrays in neuropsychiatry is the lack of availability of sequenced clone sets from model systems. While human cDNA clones have been widely available, high quality rat, mouse, and drosophilae, among others are just becoming widely available. A final factor in the application of cDNA microarrays in neuropsychiatry is cost of commercial arrays. As academic microarray facilitates become more commonplace custom made arrays will become more widely available at a lower cost allowing more widespread applications. In summary, microarray technology is rapidly having an impact on many areas of biomedical research. Radioisotope-nylon based microarrays offer alternatives that may in some cases be more sensitive, flexible, inexpensive, and universal as compared to other array formats, such as fluorescent-glass arrays. In some situations of limited RNA or exotic species, radioactive membrane microarrays may be the most practical experimental approach in studying psychiatric and neurodegenerative disorders, and other complex questions in the brain.
Animals
;
Brain
;
Cell Line
;
Clone Cells
;
DNA, Complementary*
;
Drosophila
;
Gene Expression
;
Humans
;
Membranes
;
Mice
;
Neurodegenerative Diseases
;
Neuropsychiatry
;
Oligonucleotide Array Sequence Analysis*
;
Rats
;
RNA
5.Genome-wide expression profiling of 8-chloroadenosine- and 8-chloro-cAMP-treated human neuroblastoma cells using radioactive human cDNA microarray..
Gil Hong PARK ; Jae Gol CHOE ; Hyo Jung CHOO ; Yun Gyu PARK ; Jeong Won SOHN ; Meyoung Kon KIM
Experimental & Molecular Medicine 2002;34(3):184-193
Previous reports raised question as to whether 8-chloro-cyclic adenosine 3,5-monophosphate (8-Cl-cAMP) is a prodrug for its metabolite, 8-Cl-adenosine which exerts growth inhibition in a broad spectrum of cancer cells. The present study was carried out to clarify overall cellular affects of 8-Cl-cAMP and 8-Cl-adenosine on SK-N-DZ human neuroblastoma cells by ystematically characterizing gene expression using radioactive human cDNA microarray. Microarray was prepared with PCR-amplified cDNA of 2,304 known genes spotted on nylon membranes, employing (1)P-labeled cDNAs of SK-N-DZ cells as a probe. the expression levels of approximately 100 cDNAs, representing about 8% of the total DNA elements on the array, were altered in 8-Cl-adenosine- or 8-Cl-cAMP-treated cells, respectively. The genome-wide expression of the two samples exhibited partial overlaps; different sets of up-regulated genes but the same set of down-regulated genes. 8-Cl-adenosine treatment up- egulated genes involved in differentiation and development (LIM protein, connexin 26, neogenin, neurofilament triplet L protein and p21( WAF1/CIP1)) and immune response such as natural killer cells protein 4, and down-regulated ones involved in proliferation and transformation (transforming growth factor-beta, DYRK2, urokinase-type plasminogen activator and proteins involved in transcription and translation) which were in close parallel with those by 8-Cl-cAMP. Our results indicated that the two drugs shared common genomic pathways for the down-regulation of certain genes, but used distinct pathways for the up-regulation of different gene clusters. Based on the findings, we suggest that the anti-cancer activity of 8-Cl-cAMP results at least in part through 8-Cl-adenosine. Thus, the systematic use of DNA arrays can provide insight into the dynamic cellular pathways involved in anticancer activities of chemotherapeutics.
2-Chloroadenosine/*analogs & derivatives/chemistry/*pharmacology
;
8-Bromo Cyclic Adenosine Monophosphate/*analogs & derivatives/chemistry/*pharmacology
;
Antineoplastic Agents/chemistry/*pharmacology
;
Blotting, Western
;
*Gene Expression Profiling
;
Gene Expression Regulation, Neoplastic/*drug effects
;
Genome, Human
;
Human
;
Neuroblastoma/*genetics
;
Oligonucleotide Array Sequence Analysis
;
Reproducibility of Results
;
Tumor Cells, Cultured
;
Up-Regulation/drug effects
6.The Relation of Self-Efficacy with Environmental Factors, Personality and Academic Achievement in Medical Students.
Young Mee LEE ; Byung Joo HAM ; Kyung A LEE ; Duck Sun AHN ; Meyoung Kon KIM
Korean Journal of Medical Education 2006;18(3):249-257
PURPOSE: The purpose of this study was to explore the relation of self-efficacy with environmental factors, personality, and academic achievement in medical students. METHODS: Study subjects consisted of 141 first-year medical students at Korea University Medical School during one academic year (2003~2004). All participants completed a 24-item questionnaire on self-efficacy beliefs, a 16-item questionnaire asking demographic and socioeconomic data, and the Temperament and Character Inventory (TCI). Spearman'sorrelation of selfefficacy with other variables was generated. The differences of self-efficacy scores according to the level of satisfaction with school life, total family income per month and the reasons for entering medical college were analyzed by ANOVA. RESULTS: Age and overall satisfaction with school correlated with self-confidence and total family income per month was related to self-regulation. Students who entered medical college due to the socioeconomic stability of medicine showed significantly lower preference for task difficulty than those who had other reasons for entering medical college. The GPAs of premedical studies correlated with self-regulation and the GPAs of Med 1 and the cumulative GPAs of premedical and Med I were related to the preference for task difficulty. CONCLUSION: This result supports that self-efficacy beliefs were related with some environmental factors, personality and academic achievements in medical students.
Humans
;
Korea
;
Schools, Medical
;
Students, Medical*
;
Temperament
;
Surveys and Questionnaires
7.The Development of a Pre-medical Curriculum for a Service Learning Program and the Post-implementation Evaluation.
Youn Seon CHOI ; Dae Gyeun KIM ; Duck Sun AHN ; Young Mee LEE ; Chang Duck KIM ; Byung Cheol CHUN ; Meyoung Kon KIM ; Ock Joo KIM
Korean Journal of Medical Education 2006;18(1):65-76
PURPOSE: This paper reports on the development a program to foster 'good doctors' who care for their patients with humanism and self-directed learning ability. METHODS: In order to develop the program, Korea University College of Medicine established educational committees. In collaboration, these committees discussed the direction for curriculum reorganization, performed a needs analysis of specified programs, and built realistic strategies for program management. Based upon the needs analyses, through literature review and survey studies, committee discussions and benchmarking of other medical schools, three programs were developed for rearing humanism and self-directed learning ability in medical students were developed: Service learning by experiential learning; Doctoring by small group activities; and Communication skills program by various small group activities. RESULTS: The evaluation by the pre-medical students who participated in the service learning program for one week reveals that through service learning, pre-medical students had an opportunity to obtain the attitudes that encompass the sanctity and dignity of human life and an understanding of cultural, social and religious customs and beliefs that differ from his or her own. In addition, the pre-medical students came to realize that patients' most difficult problems might be caused by non-medical factors as well as medical factors. CONCLUSION: It is needed to grope for the way that leads the active participation of students in the continuous linkage of substantial post-work evaluation and next learning of volunteering in order to make the program of educating the public spirit more than self-learning of experience.
Benchmarking
;
Cooperative Behavior
;
Curriculum*
;
Education, Medical
;
Humanism
;
Humans
;
Korea
;
Learning*
;
Problem-Based Learning
;
Schools, Medical
;
Students, Medical
8.Gene-expression profiling of titanium-cell interaction.
Chang Su KIM ; Jung Won HWANG ; Jae Jun RYU ; Sang Wan SHIN ; Sung Hwa SOHN ; Ki Nam KIM ; Meyoung Kon KIM
The Journal of Korean Academy of Prosthodontics 2005;43(3):393-408
STATEMENT OF PROBLEM: In the process of bone formation, titanium (Ti) surface roughness is an important factor modulating osteoblastic function. PURPOSE: This study was carried out to determine the effect of different Ti surface on biologic responses of a human osteoblast-like cell line (MG63). MATERIALS AND METHODS: MG63 cells were cultured on S (smooth), SLA (sandblasted largegrit and acid etching), HA (hydroxyapatite) Ti. The morphology and attachment of the cells were examined by SEM. The cDNAs prepared from total RNAs of MG63 were hybridized to a human cDNA microarray (1,152 elements). RESULTS: The appearances of the surfaces observed with SEM were different in the three types of dental substrates. The surface of SLA and HA were shown to be rougher than S. MG63 cells cultured on SLA and HA were cell-matrix interaction. In the expression of genes involved in osseointegration, upregulated genes were bone morphogenetic protein, Villin, Integrin, Insulin-like growth factors in different surfaces. Downregulated genes were fibroblast growth factor receptor 4, Bcl 2-related protein, collagen, CD4 in different surfaces. CONCLUSION: The attachment and expression of key osteogenic regulatory genes were enhanced by surface roughness of the dental materials.
Bone Morphogenetic Proteins
;
Cell Line
;
Collagen
;
Dental Materials
;
DNA, Complementary
;
Genes, Regulator
;
Humans
;
Oligonucleotide Array Sequence Analysis
;
Osseointegration
;
Osteoblasts
;
Osteogenesis
;
Receptor, Fibroblast Growth Factor, Type 4
;
RNA
;
Somatomedins
;
Titanium
9.The Relation between the High-level Resistance to Fluoroquinolones and the Over-expression of the acrA among Quinolone-Resistant Escherichia coli-Quantification of acrA by Using Real time PCR and Northern hybridization.
Byung Yeon HWANG ; Sae Yoon KEE ; Jeong Yeon KIM ; Hye Won JEONG ; Cheong Won PARK ; Yoon Hee PARK ; Meyoung Kon KIM ; Hee Jin CHEONG ; Woo Joo KIM
Infection and Chemotherapy 2005;37(4):185-192
BACKGROUND: Target point mutation of DNA topoisomerase, which is the typical mode of quinolone resistance, cannot explain high level resistance to quinolones. Therefore, many authors looked into over expression of efflux pump as the possibility. After quantificating the arcA mRNA, which controls AcrAB- TolC, the authors tried to find out the difference in the expression of arcA mRNA according to MIC of ciprofloxacin. The authors also tried to determine the usefulness of real time PCR, which is more reproducible and takes less time than preexisting immunoblot assay, through quantification of acrA. MATERIAL AND METHODS: Mutations in topoisomerase (GyrA, ParC) of 20 quinolone resistant E. coli isolates were identified by PCR and direct DNA sequencing. AcrA level was measured by real time PCR. GAPDH of E.coli was used as endogenous control. The expression of acrA was confirmed through northern hybridization method, the results obtained by real time PCR were compared. RESULTS: 1) Topoisomerase mutations were found in all quinolone resistant E. coli strains. 2) AcrA expression in fluoroquinolone-resistant E. coli was quantified by using real time PCR. There was no relationship between the ratio of acrA expression to GAPDH and MIC of ciprofloxacin. 3) With Northern hybridization, we compared the band of acrA to that of GAPDH in compactness and area. No difference in the expression according to MIC could be found. 4) The results of AcrA/GAPDH were significantly correlated between the real-time PCR and northern blot (P<0.05, correlation coefficiency 0.98). CONCLUSION: In this study, no relationship between overexpression of AcrA gene and high level fluoroquinolone resistance. Therefore, we assume that mechanism other than AcrAB efflux pump is involved in and contribute to high-level fluoroquinolone resistance. However, the degree of efflux pump expression could be confirmed with real time PCR using acrA mRNA. Therefore, real time PCR could be used in the molecular biologic study on the mechanism of resistance to antibiotics.
Anti-Bacterial Agents
;
Blotting, Northern
;
Ciprofloxacin
;
DNA Topoisomerases, Type I
;
Escherichia*
;
Fluoroquinolones*
;
Point Mutation
;
Polymerase Chain Reaction
;
Quinolones
;
Real-Time Polymerase Chain Reaction*
;
RNA, Messenger
;
Sequence Analysis, DNA
10.The Relation between the High-level Resistance to Fluoroquinolones and the Over-expression of the acrA among Quinolone-Resistant Escherichia coli-Quantification of acrA by Using Real time PCR and Northern hybridization.
Byung Yeon HWANG ; Sae Yoon KEE ; Jeong Yeon KIM ; Hye Won JEONG ; Cheong Won PARK ; Yoon Hee PARK ; Meyoung Kon KIM ; Hee Jin CHEONG ; Woo Joo KIM
Infection and Chemotherapy 2005;37(4):185-192
BACKGROUND: Target point mutation of DNA topoisomerase, which is the typical mode of quinolone resistance, cannot explain high level resistance to quinolones. Therefore, many authors looked into over expression of efflux pump as the possibility. After quantificating the arcA mRNA, which controls AcrAB- TolC, the authors tried to find out the difference in the expression of arcA mRNA according to MIC of ciprofloxacin. The authors also tried to determine the usefulness of real time PCR, which is more reproducible and takes less time than preexisting immunoblot assay, through quantification of acrA. MATERIAL AND METHODS: Mutations in topoisomerase (GyrA, ParC) of 20 quinolone resistant E. coli isolates were identified by PCR and direct DNA sequencing. AcrA level was measured by real time PCR. GAPDH of E.coli was used as endogenous control. The expression of acrA was confirmed through northern hybridization method, the results obtained by real time PCR were compared. RESULTS: 1) Topoisomerase mutations were found in all quinolone resistant E. coli strains. 2) AcrA expression in fluoroquinolone-resistant E. coli was quantified by using real time PCR. There was no relationship between the ratio of acrA expression to GAPDH and MIC of ciprofloxacin. 3) With Northern hybridization, we compared the band of acrA to that of GAPDH in compactness and area. No difference in the expression according to MIC could be found. 4) The results of AcrA/GAPDH were significantly correlated between the real-time PCR and northern blot (P<0.05, correlation coefficiency 0.98). CONCLUSION: In this study, no relationship between overexpression of AcrA gene and high level fluoroquinolone resistance. Therefore, we assume that mechanism other than AcrAB efflux pump is involved in and contribute to high-level fluoroquinolone resistance. However, the degree of efflux pump expression could be confirmed with real time PCR using acrA mRNA. Therefore, real time PCR could be used in the molecular biologic study on the mechanism of resistance to antibiotics.
Anti-Bacterial Agents
;
Blotting, Northern
;
Ciprofloxacin
;
DNA Topoisomerases, Type I
;
Escherichia*
;
Fluoroquinolones*
;
Point Mutation
;
Polymerase Chain Reaction
;
Quinolones
;
Real-Time Polymerase Chain Reaction*
;
RNA, Messenger
;
Sequence Analysis, DNA