1.Carbon monoxide activation of delayed rectifier potassium currents of human cardiac fibroblasts through diverse pathways
Hyemi BAE ; Taeho KIM ; Inja LIM
The Korean Journal of Physiology and Pharmacology 2022;26(1):25-36
To identify the effect and mechanism of carbon monoxide (CO) on delayed rectifier K+ currents (IK) of human cardiac fibroblasts (HCFs), we used the wholecell mode patch-clamp technique. Application of CO delivered by carbon monoxidereleasing molecule-3 (CORM3) increased the amplitude of outward K+ currents, and diphenyl phosphine oxide-1 (a specific IK blocker) inhibited the currents. CORM3-induced augmentation was blocked by pretreatment with nitric oxide synthase blockers (L-NG-monomethyl arginine citrate and L-NG-nitro arginine methyl ester).Pretreatment with KT5823 (a protein kinas G blocker), 1H-[1,-2,-4] oxadiazolo-[4,-3-a] quinoxalin-1-on (ODQ, a soluble guanylate cyclase blocker), KT5720 (a protein kinase A blocker), and SQ22536 (an adenylate cyclase blocker) blocked the CORM3 stimulating effect on IK . In addition, pretreatment with SB239063 (a p38 mitogen-activated protein kinase [MAPK] blocker) and PD98059 (a p44/42 MAPK blocker) also blocked the CORM3’s effect on the currents. When testing the involvement of S-nitrosylation, pretreatment of N-ethylmaleimide (a thiol-alkylating reagent) blocked CO-induced IKactivation and DL-dithiothreitol (a reducing agent) reversed this effect. Pretreatment with 5,10,15,20-tetrakis(1-methylpyridinium-4-yl)-21H,23H porphyrin manganese (III) pentachloride and manganese (III) tetrakis (4-benzoic acid) porphyrin chloride (superoxide dismutase mimetics), diphenyleneiodonium chloride (an NADPH oxidase blocker), or allopurinol (a xanthine oxidase blocker) also inhibited CO-induced IK activation. These results suggest that CO enhances IK in HCFs through the nitric oxide, phosphorylation by protein kinase G, protein kinase A, and MAPK, S-nitrosylation and reduction/oxidation (redox) signaling pathways.
2.Carbon monoxide activates large-conductance calcium-activated potassium channels of human cardiac fibroblasts through various mechanisms
Hyemi BAE ; Taeho KIM ; Inja LIM
The Korean Journal of Physiology and Pharmacology 2021;25(3):227-237
Carbon monoxide (CO) is a cardioprotectant and potential cardiovascular therapeutic agent. Human cardiac fibroblasts (HCFs) are important determinants of myocardial structure and function. Large-conductance Ca 2+ -activated K+ (BK) channel is a potential therapeutic target for cardiovascular disease. We investigated whether CO modulates BK channels and the signaling pathways in HCFs using whole-cell mode patch-clamp recordings. CO-releasing molecules (CORMs; CORM-2 and CORM-3) significantly increased the amplitudes of BK currents IBK. The CO-induced stimulating effects on IBK were blocked by pre-treatment with specific nitric oxide synthase (NOS) blockers (L-N G -monomethyl arginine citrate and L-N G -nitroarginine methyl ester). 8-bromo-cyclic GMP increased IBK. KT5823 (inhibits PKG) or ODQ (inhibits soluble guanylate cyclase) blocked the CO-stimulating effect on IBK. Moreover, 8-bromo-cyclic AMP also increased IBK, and pre-treatment with KT5720 (inhibits PKA) or SQ22536 (inhibits adenylate cyclase) blocked the CO effect. Pre-treatment with Nethylmaleimide (a thiol-alkylating reagent) also blocked the CO effect on IBK, and DLdithiothreitol (a reducing agent) reversed the CO effect. These data suggest that CO activates IBK through NO via the NOS and through the PKG, PKA, and S-nitrosylation pathways.
3.Carbon monoxide activates large-conductance calcium-activated potassium channels of human cardiac fibroblasts through various mechanisms
Hyemi BAE ; Taeho KIM ; Inja LIM
The Korean Journal of Physiology and Pharmacology 2021;25(3):227-237
Carbon monoxide (CO) is a cardioprotectant and potential cardiovascular therapeutic agent. Human cardiac fibroblasts (HCFs) are important determinants of myocardial structure and function. Large-conductance Ca 2+ -activated K+ (BK) channel is a potential therapeutic target for cardiovascular disease. We investigated whether CO modulates BK channels and the signaling pathways in HCFs using whole-cell mode patch-clamp recordings. CO-releasing molecules (CORMs; CORM-2 and CORM-3) significantly increased the amplitudes of BK currents IBK. The CO-induced stimulating effects on IBK were blocked by pre-treatment with specific nitric oxide synthase (NOS) blockers (L-N G -monomethyl arginine citrate and L-N G -nitroarginine methyl ester). 8-bromo-cyclic GMP increased IBK. KT5823 (inhibits PKG) or ODQ (inhibits soluble guanylate cyclase) blocked the CO-stimulating effect on IBK. Moreover, 8-bromo-cyclic AMP also increased IBK, and pre-treatment with KT5720 (inhibits PKA) or SQ22536 (inhibits adenylate cyclase) blocked the CO effect. Pre-treatment with Nethylmaleimide (a thiol-alkylating reagent) also blocked the CO effect on IBK, and DLdithiothreitol (a reducing agent) reversed the CO effect. These data suggest that CO activates IBK through NO via the NOS and through the PKG, PKA, and S-nitrosylation pathways.
4.Toxoplasma gondii B1 Gene Detection in Feces of Stray Cats around Seoul, Korea and Genotype Analysis of Two Laboratory-Passaged Isolates.
Bong Kwang JUNG ; Sang Eun LEE ; Hyemi LIM ; Jaeeun CHO ; Deok Gyu KIM ; Hyemi SONG ; Min Jae KIM ; Eun Hee SHIN ; Jong Yil CHAI
The Korean Journal of Parasitology 2015;53(3):259-263
The increasing prevalence of Toxoplasma gondii infection in the human population in the Republic of Korea (= Korea) is due to various reasons such as an increase in meat consumption. However, the importance of cats in transmitting T. gondii infection through oocysts to humans has seldom been assessed. A total of 300 fecal samples of stray cats captured around Seoul from June to August 2013 were examined for T. gondii B1 gene (indicating the presence of oocysts) using nested-PCR. Fourteen (4.7%) of 300 cats examined were positive for B1 gene. Female cats (7.5%) showed a higher prevalence than male cats (1.4%). Cats younger than 3 months (5.5%) showed a higher prevalence than cats (1.5%) older than 3 months. For laboratory passage of the positive samples, the fecal suspension (0.2 ml) of B1 gene positive cats was orally inoculated into experimental mice. Brain tissues of the mice were obtained after 40 days and examined for the presence of tissue cysts. Two isolates were successfully passaged (designated KNIH-1 and KNIH-2) and were molecularly analyzed using the SAG5D and SAG5E gene sequences. The SAG5D and SAG5E gene sequences showed high homologies with the ME49 strain (less virulent strain). The results indicated the importance of stray cats in transmitting T. gondii to humans in Korea, as revealed by detection of B1 gene in fecal samples. T. gondii isolates from cats were successfully passaged in the laboratory for the first time in Korea.
Animals
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Cat Diseases/diagnosis/epidemiology/*parasitology
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Cats
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Feces/*parasitology
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Female
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Genotype
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Humans
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Male
;
Mice
;
Protozoan Proteins/genetics
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Seoul/epidemiology
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Toxoplasma/genetics/*isolation & purification
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Toxoplasmosis/epidemiology/parasitology/transmission
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Toxoplasmosis, Animal/diagnosis/epidemiology/*parasitology
5.Interaction of Vitamin D and Smoking on Inflammatory Markers in the Urban Elderly.
Hyemi LEE ; Kyoung Nam KIM ; Youn Hee LIM ; Yun Chul HONG
Journal of Preventive Medicine and Public Health 2015;48(5):249-256
OBJECTIVES: Epidemiological studies have reported that vitamin D deficiency is associated with inflammatory disease. Smoking is a well-known risk factor for inflammation. However, few studies have investigated the interactive effect of vitamin D deficiency and smoking on inflammation. This study aims to investigate the interaction of vitamin D and smoking with inflammatory markers in the urban elderly. METHODS: We used data from the Korean Elderly Environmental Panel Study, which began in August 2008 and ended in August 2010, and included 560 Koreans > or =60 years old living in Seoul. Data was collected via questionnaires that included items about smoking status at the first visit. Vitamin D levels, high-sensitivity C-reactive protein (hs-CRP), and white blood cell (WBC) counts were repeatedly measured up to three times. RESULTS: The association of vitamin D and hs-CRP was significant after adjusting for known confounders (beta=-0.080, p=0.041). After separate analysis by smoking status, the association of vitamin D deficiency and hs-CRP in smokers was stronger than that in nonsmokers (smokers: beta=-0.375, p=0.013; non-smokers: beta=-0.060, p=0.150). Smoking status was an effect modifier that changed the association between vitamin D deficiency and hs-CRP (interaction estimate: beta=-0.254, p=0.032). Vitamin D was not significantly associated with WBC count (beta=0.003, p=0.805). CONCLUSIONS: Vitamin D deficiency was associated with hs-CRP in the urban elderly. Smoking status was an effect modifier of this association. Vitamin D deficiency was not significantly associated with WBC count.
25-Hydroxyvitamin D 2/blood
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Aged
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Biomarkers/blood
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Body Mass Index
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C-Reactive Protein/analysis
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Female
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Humans
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Inflammation
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Leukocyte Count
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Male
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Middle Aged
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*Smoking
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Urban Population
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Vitamin D/*blood
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Vitamin D Deficiency/diagnosis
6.Anisakis pegreffii Larvae in Sea Eels (Astroconger myriaster) from the South Sea, Republic of Korea.
Jaeeun CHO ; Hyemi LIM ; Bong Kwang JUNG ; Eun Hee SHIN ; Jong Yil CHAI
The Korean Journal of Parasitology 2015;53(3):349-353
Anisakis simplex sensu stricto (s.s.), Anisakis pegreffii, Anisakis berlandi (=A. simplex sp. C), and Anisakis typica are the 4 major species of Anisakis type I larvae. In the Republic of Korea (Korea), A. pegreffii, A. berlandi, and A. typica larvae in fish hosts has seldom been documented. In this study, molecular analysis was performed on Anisakis larvae from the sea eels (Astroconger myriaster), the major source of human anisakiasis in Korea, collected from Tongyeong City, a southern coastal area of Korea. All 20 sea eels examined were infected with Anisakis type I larvae (160 larvae; 8 per fish). Their species were analyzed using PCR-RFLP patterns and nucleotide sequences of internal transcribed spacers (ITS1, 5.8 subunit gene, and ITS2) and mitochondrial cytochrome c oxidase 2 (cox2). Most (86.8%; 112/129) of the Anisakis type I larvae were A. pegreffii, and 7.8% (10/129) were A. typica. The remaining 5.4% (7/129) was not identified. Thus, A. pegreffii is the major species of anisakid larvae in sea eels of the southern coast of Korea.
Animals
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Anisakiasis/parasitology/*veterinary
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Anisakis/classification/genetics/*isolation & purification
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DNA, Helminth/genetics
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DNA, Ribosomal Spacer/genetics
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*Eels/growth & development
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Fish Diseases/*parasitology
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Larva/classification/genetics
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Phylogeny
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Polymorphism, Restriction Fragment Length
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Republic of Korea
7.Physical Activity- and Alcohol-dependent Association Between Air Pollution Exposure and Elevated Liver Enzyme Levels: An Elderly Panel Study.
Kyoung Nam KIM ; Hyemi LEE ; Jin Hee KIM ; Kweon JUNG ; Youn Hee LIM ; Yun Chul HONG
Journal of Preventive Medicine and Public Health 2015;48(3):151-169
OBJECTIVES: The deleterious effects of air pollution on various health outcomes have been demonstrated. However, few studies have examined the effects of air pollution on liver enzyme levels. METHODS: Blood samples were drawn up to three times between 2008 and 2010 from 545 elderly individuals who regularly visited a community welfare center in Seoul, Korea. Data regarding ambient air pollutants (particulate matter < or =2.5 mum [PM2.5], nitrogen dioxide [NO2], ozone [O3], carbon monoxide, and sulfur dioxide) from monitoring stations were used to estimate air pollution exposure. The effects of the air pollutants on the concentrations of three liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma-glutamyltranspeptidase [gamma-GTP)]) were evaluated using generalized additive and linear mixed models. RESULTS: Interquartile range increases in the concentrations of the pollutants showed significant associations of PM2.5 with AST (3.0% increase, p=0.0052), ALT (3.2% increase, p=0.0313), and gamma-GTP (5.0% increase, p=0.0051) levels; NO2 with AST (3.5% increase, p=0.0060) and ALT (3.8% increase, p=0.0179) levels; and O3 with gamma-GTP (5.3% increase, p=0.0324) levels. Significant modification of these effects by exercise and alcohol consumption was found (p for interaction <0.05). The effects of air pollutants were greater in non-exercisers and heavy drinkers. CONCLUSIONS: Short-term exposure to air pollutants such as PM2.5, NO2, and O3 is associated with increased liver enzyme levels in the elderly. These adverse effects can be reduced by exercising regularly and abstinence from alcohol.
Aged
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Aged, 80 and over
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Air Pollutants/analysis/*toxicity
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Alanine Transaminase/blood
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*Alcohol Drinking
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Aspartate Aminotransferases/blood
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Environmental Exposure
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*Exercise
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Female
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Humans
;
Linear Models
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Liver/*drug effects/enzymology
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Male
;
Nitrogen Dioxide/chemistry/toxicity
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Ozone/chemistry/toxicity
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Particulate Matter/analysis/toxicity
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Sulfur Dioxide/chemistry/toxicity
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gamma-Glutamyltransferase/blood
8.Development of a user-friendly training software for pharmacokinetic concepts and models
Seunghoon HAN ; Byounghee LIM ; Hyemi LEE ; Soo Hyun BAE
Translational and Clinical Pharmacology 2018;26(4):166-171
Although there are many commercially available training software programs for pharmacokinetics, they lack flexibility and convenience. In this study, we develop simulation software to facilitate pharmacokinetics education. General formulas for time courses of drug concentrations after single and multiple dosing were used to build source code that allows users to simulate situations tailored to their learning objectives. A mathematical relationship for a 1-compartment model was implemented in the form of differential equations. The concept of population pharmacokinetics was also taken into consideration for further applications. The source code was written using R. For the convenience of users, two types of software were developed: a web-based simulator and a standalone-type application. The application was built in the JAVA language. We used the JAVA/R Interface library and the ‘eval()’ method from JAVA for the R/JAVA interface. The final product has an input window that includes fields for parameter values, dosing regimen, and population pharmacokinetics options. When a simulation is performed, the resulting drug concentration time course is shown in the output window. The simulation results are obtained within 1 minute even if the population pharmacokinetics option is selected and many parameters are considered, and the user can therefore quickly learn a variety of situations. Such software is an excellent candidate for development as an open tool intended for wide use in Korea. Pharmacokinetics experts will be able to use this tool to teach various audiences, including undergraduates.
Education
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Indonesia
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Korea
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Learning
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Methods
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Pharmacokinetics
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Pliability
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Simulation Training
9.Four Cases of Taenia saginata Infection with an Analysis of COX1 Gene.
Jaeeun CHO ; Bong Kwang JUNG ; Hyemi LIM ; Min Jae KIM ; Thanapon YOOYEN ; Dongmin LEE ; Keeseon S EOM ; Eun Hee SHIN ; Jong Yil CHAI
The Korean Journal of Parasitology 2014;52(1):79-83
Human taeniases had been not uncommon in the Republic of Korea (=Korea) until the 1980s. The prevalence decreased and a national survey in 2004 revealed no Taenia egg positive cases. However, a subsequent national survey in 2012 showed 0.04% (10 cases) prevalence of Taenia spp. eggs suggesting its resurgence in Korea. We recently encountered 4 cases of Taenia saginata infection who had symptoms of taeniasis that included discharge of proglottids. We obtained several proglottids from each case. Because the morphological features of T. saginata are almost indistinguishable from those of Taenia asiatica, molecular analyses using the PCR-RFLP and DNA sequencing of the cytochrome c oxidase subunit 1 (cox1) were performed to identify the species. The PCR-RFLP patterns of all of the 4 specimens were consistent with T. saginata, and the cox1 gene sequence showed 99.8-100% identity with that of T. saginata reported previously from Korea, Japan, China, and Cambodia. All of the 4 patients had the history of travel abroad but its relation with contracting taeniasis was unclear. Our findings may suggest resurgence of T. saginata infection among people in Korea.
Adult
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Animals
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Cluster Analysis
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DNA Fingerprinting
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Electron Transport Complex IV/*genetics
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Female
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Humans
;
Male
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Middle Aged
;
Phylogeny
;
Polymerase Chain Reaction
;
Polymorphism, Restriction Fragment Length
;
Republic of Korea
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Sequence Analysis, DNA
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Sequence Homology
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Taenia saginata/*classification/genetics/*isolation & purification
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Taeniasis/*diagnosis/*parasitology
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Travel
10.Low Prevalence of Somatic TERT Promoter Mutations in Classic Papillary Thyroid Carcinoma.
Min Ji JEON ; Won Gu KIM ; Soyoung SIM ; Seonhee LIM ; Hyemi KWON ; Tae Yong KIM ; Young Kee SHONG ; Won Bae KIM
Endocrinology and Metabolism 2016;31(1):100-104
BACKGROUND: Transcriptional activating mutations of telomerase reverse transcriptase (TERT) are associated with more aggressive thyroid cancer. We evaluated the significance of TERT promoter mutations in Korean patients with classic papillary thyroid cancer (PTC). METHODS: Genomic DNA was isolated from four thyroid cancer cell lines and 35 fresh-frozen PTC tissues. TERT promoter mutations (C228T and C250T) and the BRAF V600E mutation were evaluated by polymerase chain reaction amplification and direct sequencing. RESULTS: The CC228229TT mutation in the TERT promoter was detected in BCPAP cells and the C250T mutation was found in 8505C cells. No TERT promoter mutation was observed in Cal-62 or ML-1 cells. The C228T mutation was found in only 1 of 35 (2.8%) PTCs and no C250T mutations were detected in any of the study subjects. The BRAF V600E mutation was found in 20 of 35 (57.1%) PTCs. One patient with the C228T TERT mutation also harbored the BRAF V600E mutation and developed a recurrence. CONCLUSION: The prevalence of somatic TERT promoter mutations was low in Korean patients with classic PTC. Therefore, the prognostic role of TERT promoter mutations might be limited in this patient cohort.
Cell Line
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Cohort Studies
;
DNA
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Humans
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Polymerase Chain Reaction
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Prevalence*
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Recurrence
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Telomerase
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Thyroid Gland*
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Thyroid Neoplasms*