Publications by authors named "Soo Yong Choi"

Background And Aims: Cold snare polypectomy (CSP) has been reported as safe and effective method for the removal of small colorectal polyps. However, some studies showed low R0 resection rate. Underwater endoscopic mucosal resection is an effective technique to increase the proportions of complete resection.

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Global DNA hypomethylation is proposed as a potential biomarker for cancer risk associated with genomic instability, which is an important factor in radiation-induced cancer. However, the associations among radiation exposure, changes in DNA methylation, and carcinogenesis are unclear. The aims of this study were (1) to examine whether low-level occupational radiation exposure induces genomic DNA hypomethylation; and (2) to determine the relationships between radiation exposure, genomic DNA hypomethylation and radiation-induced genomic instability (RIGI) in industrial radiographers.

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Basaloid squamous cell carcinoma of the esophagus is very rare. Further, polypoid type of esophageal cancer is also rare. We have recently treated a case of basaloid squamous cell carcinoma which presented as a 1.

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Gallic acid [3,4,5-trihydroxybenzoic acid (GA)], a natural phytochemical, is known to have a variety of cellular functions including beneficial effects on metabolic syndromes. However, the molecular mechanism by which GA exerts its beneficial effects is not known. Here we report that GA plays its role through the activation of AMP-activated protein kinase (AMPK) and by regulating mitochondrial function via the activation of peroxisome proliferator-activated receptor-γ coactivator1α (PGC1α).

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There are public concerns regarding possible carcinogenic or cancer-promoting effects of radiofrequency electromagnetic fields (RF-EMFs) because of the extensive use of wireless mobile phones and other telecommunication devices in daily life. However, so far it is unclear if non-thermal exposure of single EMF exposure in animal studies has a direct influence on carcinogenesis. Here, carcinogenic effects of combined signal RF-EMFs on AKR/J mice, which were used for the lymphoma animal model, were investigated.

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We examined the histological changes by radiofrequency (RF) fields on rat testis, specifically with respect to sensitive processes such as spermatogenesis. Male rats were exposed to 848.5 MHz RF for 12 weeks.

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Previously, two case-control studies and a cohort study strongly suggested that Panax ginseng C.A. Meyer exerted non-organ-specific preventive effects against cancer.

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The micronucleus-centromere assay using a pan-centromeric probe was used to assess chromosomal damage in lymphocytes of 47 industrial radiographers occupationally exposed to low dose ionizing radiation and 47 controls. The influence of genotype of DNA repair genes (XRCC1(399), XRCC3(241) and XPD(751)) on micronuclei (MN) frequency was also investigated. Centromere negative micronuclei (MNC-) frequency was significantly higher in radiographers than in controls, whereas similar centromere positive micronuclei (MNC+) frequency was observed in both groups.

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In order to evaluate possible tumorigenic effects of a 20 kHz intermediate frequency triangular magnetic field (IF), a frequency emitted from TV and PC monitors at 6.25 microT rms, which is the regulated exposure limit of magnetic field for the public in Korea, mammary tumors were produced in female Sprague-Dawley rats by oral intubation of dimethylbenz(a)anthracene (DMBA), lung tumors in ICR mice by scapular region injection of benzo(a)pyrene (BP), and skin tumors in female ICR mice by topical application of DMBA and tetradecanoylphorbol ester (TPA). IF was applied 8 h/day for 14 weeks beginning the day after DMBA treatment for mammary tumor experiment, for 6 weeks after weaning for lung tumor, and for 20 weeks beginning 1 week after DMBA application for skin tumor experiment.

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Sprague-Dawley rats (10 each of male and female per group for sham and magnetic field exposed) were exposed in a carrousel irradiator to 20 kHz intermediate frequency (IF) magnetic field at 6.25 microT rms for 8 h/day, 5 days/week for 90 days. Urine analysis (pH, serum glucose, protein, ketone bodies, RBC, WBC, bilirubin, urobilinogen, and specific gravity), blood analysis [WBC, RBC, hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), thrombocyte count, and leucocyte count], blood biochemistry (total protein, blood urea nitrogen, creatinine, glucose, total bilirubin, total cholesterol, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, and lactate dehydrogenase), and histopathological analysis for organs such as liver, kidney, testis, ovary, spleen, brain, heart, and lung were performed on day 90.

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Purpose: Mediastinal staging of non-small cell lung cancer can be markedly improved by FDG-PET scan, but the problem of false staging of mediastinal nodes by PET scan in non-small cell lung cancer has not yet been overcome. The aim of this study was to identify the mechanism underlying the false staging of mediastinal nodes by FDG-PET in the case of non-small cell lung cancer.

Materials And Methods: To evaluate the factors determining the FDG uptake in mediastinal nodes, FDG-PET was performed preoperatively, and mediastinal dissection with pulmonary resection was performed in 62 patients with NSCLC.

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