Ji Young Choi

Seoul National University, Sŏul, Seoul, South Korea

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Publications (73)212.98 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Endoscopic resection (ER) of superficial esophageal neoplasm (SEN) is a technically difficult procedure. We investigated the clinical outcomes of ER for SEN to determine its feasibility and effectiveness. Subjects who underwent ER for SEN at Asan Medical Center between December 1996 and December 2010 were eligible. The clinical features of patients and tumors, histopathological characteristics, adverse events, ER results and survival were investigated. A total of 129 patients underwent ER for 147 SENs. En bloc resection (EnR) was performed in 118 lesions (80.3%). Complete resection (CR) was accomplished in 128 lesions (86.5%), and curative resection (CuR) was performed in 118 lesions (79.7%). The EnR, CR, and CuR rates were significantly greater in the endoscopic submucosal dissection group when compared to those in the endoscopic resection group. Adverse events occurred in 22 patients (17.1%), including bleeding (n=2, 1.6%), perforation (n=12, 9.3%), and stricture (n=8, 6.2%). Local tumor recurrence occurred in 2.0% of patients during a median follow-up of 34.8 months. The 5-year overall and disease-specific survival rates were 94.0% and 97.5%, respectively. ER is a feasible and effective method for the treatment of SEN as indicated by favorable clinical outcomes. (Gut Liver, Published online December 5, 2014).
    Gut and liver 12/2014; · 1.49 Impact Factor
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    ABSTRACT: The use of endoscopic submucosal dissection (ESD) for the treatment of minute submucosal (SM) invasive cancer that fulfills the current expanded criteria remains controversial. This study investigated the clinicopathological parameters of patients with sm1 gastric cancers to predict lymph node metastasis (LNM) and evaluate the feasibility of ESD as a curative treatment.
    Surgical Endoscopy 09/2014; · 3.31 Impact Factor
  • The American Journal of Gastroenterology 07/2014; 109(7):1081. · 9.21 Impact Factor
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    ABSTRACT: Little is known about the effects of periodic endoscopic screening before detection of primary gastric cancer. We compared clinical outcomes in patients who did and did not undergo endoscopy before diagnosis. Between January 2009 and November 2011, 769 patients were referred to Asan Medical Center after diagnosis of gastric cancer. Clinical outcomes were compared in patients who had (n=512) and had not (n=257) undergone endoscopic screening before diagnosis of gastric cancer. Factors about resectability and possibility of endoscopic resection were analyzed. In the nonexamined group, 225 patients (87.5%) had resectable gastric cancers and were treated surgically (n=151, 67.1%) or by endoscopic resection (n=74, 32.9%). In the examined group, 493 (96.3%) had resectability and were resected surgically (n=243, 49.3%) or endoscopically (n=250, 50.7%). Multivariate analysis showed that symptoms, no endoscopic screening, and lower serum albumin were associated with unresectability. Of the 718 resectable tumors, 394 underwent surgery and 324 underwent endoscopic resection. Multivariate analysis showed that older age, no symptoms, ≤1 year interval endoscopy, and higher serum albumin were associated with endoscopic resection. Previous endoscopy can increase gastric cancer resectability. Moreover, a ≤1 year interval from endoscopic examination can increase the possibility of endoscopic resection.
    Hepato-gastroenterology 07/2014; 61(133):1465-71. · 0.91 Impact Factor
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    ABSTRACT: This study revealed that monoterpene and sesquiterpene hydrocarbons, and their oxygenated derivatives were the major volatile compounds in Korean mugwort extracted by both simultaneous steam distillation and solvent extraction and headspace solid-phase microextraction. In particular, β-caryophyllene was the most predominant compound. Furthermore, 1,8-cineol, described as camphoraceous and minty notes, was found to be the most potent aroma-active compound of Korean mugwort, followed by (Z)-3-hexenal (described as green and apple-like notes), γ-terpinene (described as grassy note), and (E,Z)-2,6-nonadienal (described as cucumber-like and green notes). Moreover, ethyl 2-methylpropanoate, methyl 3-methylbutanoate, and ethyl 2-methylbutanoate could contribute to sweet and fruity notes of Korean mugwort with their characteristic odor properties.
    Journal of the Korean Society for Applied Biological Chemistry 06/2014; · 0.54 Impact Factor
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    ABSTRACT: The purpose of the present study was to first examine whether childhood abuse predicts symptom complexity, as indicated by the number of clinically elevated scales on the MMPI-2 in an adult clinical sample. Secondly, we investigated whether emotion regulation difficulties mediated the relationship between childhood abuse and symptom complexity. A total of 162 adult outpatients not presenting with psychotic symptoms completed the Korean Childhood Trauma Questionnaire (K-CTQ), Life Events Checklist (LEC), Difficulties in Emotion Regulation Scale (DERS), and Korean Minnesota Multiphasic Personality Inventory-2 (MMPI-2). Partial correlation analysis results indicated that after controlling for the presence of adulthood trauma, childhood abuse was associated with more symptom complexity, or more clinically elevated scales on the MMPI-2. Furthermore, structural equation modeling results showed that emotion regulation difficulties partially mediated the relationship between childhood abuse and symptom complexity. These findings indicate that individuals who had experienced childhood abuse evidence simultaneous presentation of diverse clinical symptoms.
    Child Abuse & Neglect 05/2014; · 2.47 Impact Factor
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    ABSTRACT: OBJECTIVES:Although many epidemiologic studies have shown that Helicobacter pylori (H. pylori) eradication has prophylactic effects on gastric cancer, their results are less clear in high-risk populations. We conducted this study to examine whether H. pylori eradication would affect the occurrence of metachronous gastric cancer after endoscopic resection in patients with early gastric cancer.METHODS:We retrospectively analyzed 2,089 adults who underwent endoscopic resection of gastric low-grade neoplasia, high-grade neoplasia, or differentiated invasive neoplasia from 2004 to 2008 at Asan Medical Center. Of these, a total of 1,007 patients with early gastric cancer were enrolled in this study. We evaluated the demographic data, the pathology, and the incidence of metachronous recurrence by dividing them into three groups: those without active H. pylori infection (Hp negative group, n=340), those who successfully underwent H. pylori eradication (eradicated group, n=485), and those who failed or did not undergo H. pylori eradication (noneradicated group, n=182).RESULTS:Metachronous recurrence was diagnosed in 75 patients, including 17 in the Hp, 34 in the eradicated, and 24 in the noneradicated groups. Median time to metachronous recurrence was 18 months (range, 7-75 months). The incidence of metachronous gastric cancer was 10.9 cases per 1,000 person-years in the Hp negative group, 14.7 cases per 1,000 person-years in the eradicated group, and 29.7 cases per 1,000 person-years in the noneradicated group. The hazard ratios in the noneradicated group compared with the Hp negative and eradicated groups were 2.5 (P<0.01) and 1.9 (P=0.02), respectively. H. pylori eradication reduced metachronous recurrence of gastric neoplasm, which was also shown in the secondary analysis of 1,487 patients with low-grade neoplasia and early gastric cancer.CONCLUSIONS:Successful H. pylori eradication may reduce the occurrence of metachronous gastric cancer after endoscopic resection in patients with early gastric cancer.Am J Gastroenterol advance online publication, 17 December 2013; doi:10.1038/ajg.2013.404.
    The American Journal of Gastroenterology 12/2013; · 9.21 Impact Factor
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    ABSTRACT: Endoscopic forceps biopsy (EFB) is a major diagnostic procedure for gastric epithelial neoplasia (GEN). However, discrepancy between the result of EFB and endoscopic resection (ER) is not uncommon. Thus, there is controversy over whether specimens obtained by EFB are optimal for diagnosis of GEN. We investigated the discrepancy between EFB and ER in the diagnosis of GEN. A total of 1,850 GEN cases were histologically diagnosed with EFB, including 954 low-grade dysplasias (LGDs), 315 high-grade dysplasias (HGDs), and 581 carcinomas. Following diagnosis with EFB, all patients were treated with ER. We retrospectively reviewed the pathologic findings and patient characteristics and analyzed predictors for the discrepancy between the two procedures (largest diameter, number of biopsy fragments, number of biopsy fragments/largest diameter, location, macroscopic type, color, surface unevenness, and erosion). The overall discrepancy rate between EFB and ER was 31.7 % (587/1,850). Among the discordant group, 440 (23.9 %) cases showed a higher grade of disease after ER; 229 of the 954 LGDs (24.0 %) were diagnosed as HGD or carcinoma, 166 of the 315 HGDs (52.7 %) as carcinoma, and 45 of the 581 differentiated carcinomas (7.7 %) as undifferentiated carcinoma. In the LGD group with EFB, the largest diameter (≥1.8 cm; P < 0.001), surface unevenness (P = 0.014), and depressed macroscopic type (P < 0.001) were factors associated with discrepancy. In the carcinoma group with EFB, flat macroscopic type (P = 0.043) was the only significant factor. In the HGD group with EFB, there were no significant factors for discrepancy. EFB can be insufficient for diagnosing GENs, and ER can be considered not only as treatment but also as a diagnostic modality in GEN. It is especially pertinent to all cases of HGD regardless of their endoscopic features and to cases of LGDs with the largest lesion diameter ≥1.8 cm, surface unevenness, or a depressed macroscopic type.
    Surgical Endoscopy 12/2013; · 3.31 Impact Factor
  • Ji Young Choi, Kyung Ja Oh
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    ABSTRACT: The purpose of the present study was to identify the mediating effects of emotion regulation on the association between cumulative childhood trauma and behavior problems in sexually abused children in Korea, using structural equation modeling (SEM). Data were collected on 171 children (ages 6-13 years) referred to a public counseling center for sexual abuse in Seoul, Korea. Cumulative childhood traumas were defined on the basis of number of traumas (physical abuse, witnessing domestic violence, neglect, traumatic separation from parent, and sexual abuse) and the severity and duration of traumas. Children were evaluated by their parents on emotion regulation using the Emotion Regulation Checklist and internalizing and externalizing behavior problems using the Korean-Child Behavior Checklist. SEM analyses confirmed the complete mediation model, in which emotion dysregulation fully mediates the relationship between cumulative childhood traumas and internalizing/externalizing behavior problems. These findings indicate that emotion regulation is an important mechanism that can explain the negative effects of cumulative childhood traumas and that there is a need to focus on emotion regulation in sexually abused children exposed to cumulative trauma.
    Child abuse & neglect 10/2013; · 2.34 Impact Factor
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    ABSTRACT: Six gram-negative, non-fermentative bacteria, which were designated as strains 11-0202T, 11-0607, LUH13522, LUH8638, LUH10268, and LUH10288 were isolated from soil in South Korea, from soil of a beetfield in Germany, soil in the Netherlands, and sediment of integrated fish in Malaysia and Thailand, respectively. Based on 16S rRNA, rpoB, and gyrB gene sequences, they represented a novel species of Acinetobacter. Their 16S rRNA gene sequences showed the greatest pairwise similarity to A. beijerinckii (97.9 to 98.4%). A. johnsonii and A. bouvetii were the species showing the greatest similarities with the six strains in rpoB and gyrB gene sequences, but they showed sequence divergences (85.4-87.6 and 78.1-82.7%, respectively). A strains 11-0202T displayed low DNA-DNA reassociation values less than 40% with the closely related Acinetobacter species. The strains utilized 2,3-butanediol, ethanol, and DL-lactate as sole carbon sources. Cellular fatty acid (CFA) analyses showed similarities to those of related Acinetobacter species: summed feature 3 (C16:1 ω7c, C16:1 ω6c)' (26.0-27.0%), C18:1 ω9c (22.1-23.4%), C16:0 (17.3%-22.0%), and C12:0 (9.2-12.4%). On the basis of current findings, it is concluded that the six strains represent a novel species, for which the name Acinetobacter kookii sp. nov. is proposed. The type strain is strain 11-0202T (= KCTC 32033T = JCM 18512T).
    International Journal of Systematic and Evolutionary Microbiology 08/2013; · 2.79 Impact Factor
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    ABSTRACT: The 4-propargylamino-1,8-naphthalimide based fluorescent probe 1 has been explored as a sensor for selective detection of Au(3+). 4-Amino-1,8-naphthalimides, that possess typical intramolecular charge transfer (ICT) electronic characteristics, have been widely used as versatile platforms for fluorescent probes. The newly designed probe 1 contains a propargylamine moiety at C-4 of the naphthalimide chromophore that reacts with Au(3+) to generate a product that has distinctly different electronic properties from 1. Specifically, the probe undergoes a remarkable change in its absorption spectrum upon addition of Au(3+) that is associated with a distinct color change from yellow to light pink. In addition, a blue shift of ca. 56nm also takes place in the emission spectra of the probe. Consequently, 1 serves as a reaction-based sensor or so called chemodosimeter for Au(3+). Importantly, surfactants enhance the rate of reaction of 1 with Au(3+), thus, enhancing its use as a real time sensor. Finally, the results of studies probing its application to bioimaging of Au(3+) in live cells show that the probe 1 has a unique ability to sense Au(3+) in cells and, in particular, in lipid droplets within cells.
    Biosensors & Bioelectronics 06/2013; 49C:438-441. · 6.45 Impact Factor
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    ABSTRACT: Recent analysis of prokaryotic N(ε) -lysine-acetylated proteins highlights the post-translational regulation of a broad spectrum of cellular proteins. However, the exact role of acetylation remains unclear due to a lack of acetylated proteome data in prokaryotes. Here, we present the N(ε) -lysine-acetylated proteome of gram-positive thermophilic Geobacillus kaustophilus. Affinity enrichment using acetyl-lysine-specific antibodies followed by LC-MS/MS analysis revealed 253 acetylated peptides representing 114 proteins. These acetylated proteins include not only common orthologs from mesophilic Bacillus counterparts, but also unique G. kaustophilus proteins, indicating that lysine acetylation is pronounced in thermophilic bacteria. These data complement current knowledge of the bacterial acetylproteome and provide an expanded platform for better understanding of the function of acetylation in cellular metabolism. This article is protected by copyright. All rights reserved.
    Proteomics 05/2013; · 3.97 Impact Factor
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    ABSTRACT: BACKGROUND: There are insufficient reports on the outcomes and local recurrence rates for gastric neoplasms treated using argon plasma coagulation (APC). The purpose of this study was to analyze the clinical outcomes in early gastric cancer or gastric adenoma patients following APC treatment. METHODS: Seventy-one patients were enrolled and all underwent APC at the Asan Medical Center between July 2007 and August 2011. Clinical and oncological outcomes were analyzed. RESULTS: The median follow-up period was 20 months (interquartile range 13-29 months). Among the 71 patients we evaluated, nonlifting after submucosal saline injection was found in 35 patients and 15 patients (21.2 %) experienced local recurrence with a median period of 10 months (IQR 5-13 months). The rate of local recurrence was higher in the nonlifting group and the 40-W group than in the lifting group and the 60- or 80-W groups (31.4 vs. 11.1 %, p = 0.045 and 31.7 vs. 6.7 %, p = 0.017, respectively). Multivariate analysis showed that the power setting with the 40-W and nonlifting groups after submucosal injection was associated with local recurrence. CONCLUSIONS: APC therapy after submucosal saline injection using high power (60 or 80 W) appears to be an effective alternative in the management of gastric neoplasm.
    Surgical Endoscopy 02/2013; · 3.31 Impact Factor
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    ABSTRACT: One hundred and twenty-one isolates of S. maltophilia complex were collected from seven Korean hospitals. Species and groups were identified using partial gyrB gene sequences and antimicrobial susceptibility testing was performed using a broth microdilution method. Based on partial gyrB gene sequences, 118 isolates were identified to belong to S. maltophilia complex including S. maltophilia, S. pavanii, Pseudomonas beteli, P. geniculata, and P. hibisciola. S. maltophilia were further divided into three groups, I to III. While S. maltophilia groups II and III were clustered into Clade A with S. pavanii and P. beteli, S. maltophilia group I was clustered into Clade B with P. geniculata and P. hibisciola. For all S. maltophilia complex isolates, resistance rate to trimethoprim/sulfamethoxazole (TMP/SMX) was very high (30.5%). Antimicrobial resistance rates were varied by species or groups of S. maltophilia complex. Isolates of Clade A showed significantly lower antimicrobial resistance rates than those of Clade B; while 25.0% of Clade A isolates were multidrug-resistant, 46.0% of Clade B isolates were multidrug-resistant (P 0.001). In this study, high antimicrobial resistance rates, particularly to TMP/SMX, were identified among S. maltophilia complex isolates from Korea. Distinct groups among S. maltophilia complex isolates were revealed and antimicrobial resistance rates differed among those groups. These data suggest consideration of alternative agents to TMP/SMX to treat S. maltophilia infections and warrant importance of accurate identification of appropriate selection of treatment option.
    Journal of Medical Microbiology 02/2013; · 2.27 Impact Factor
  • Ji Young Choi, Kyung Ja Oh
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    ABSTRACT: The purpose of the present study was to explore the effects of multiple interpersonal traumas on psychiatric diagnosis and behavior problems of sexually abused children in Korea. With 495 children (ages 4-13 years) referred to a public counseling center for sexual abuse in Korea, we found significant differences in the rate of psychiatric diagnoses (r = .23) and severity of behavioral problems (internalizing d = 0.49, externalizing d = 0.40, total d = 0.52) between children who were victims of sexual abuse only (n = 362) and youth who were victims of interpersonal trauma experiences in addition to sexual abuse (n = 133). The effects of multiple interpersonal trauma experiences on single versus multiple diagnoses remained significant in the logistic regression analysis where demographic variables, family environmental factors, sexual abuse characteristics, and postincident factors were considered together, odds ratio (OR) = 0.44, 95% confidence interval (CI) = [0.25, 0.77], p < .01. Similarly, multiple regression analyses revealed a significant effect of multiple interpersonal trauma experiences on severity of behavioral problems above and beyond all aforementioned variables (internalizing β =.12, p = .019, externalizing β = .11, p = .036, total β = .14, p =.008). The results suggested that children with multiple interpersonal traumas are clearly at a greater risk for negative consequences following sexual abuse.
    Journal of Traumatic Stress 02/2013; 26(1):149-57. · 2.72 Impact Factor
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    Biosensors and Bioelectronics. 01/2013; 49:438–441.
  • Ji Young Choi, Dabin Kim, Juyoung Yoon
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    ABSTRACT: A new hydroxypyrene-based sensor 1 was designed and synthesized as a Zn2+ selective colorimetric and fluorescent chemosensor. This chemosensor showed a new UV–vis absorption peak (λmax = 498 nm) with Zn2+, which can be attributed to an internal charge transfer (ICT) mechanism. In addition, Zn2+ induced a highly selective “turn-on” fluorescence enhancement at long wavelength (λmax = 588 nm) in a buffered system. A significant fluorescence enhancement was observed upon the addition of Zn2+. The combination of two phenol groups on the pyrene and phenyl moieties as well as a conjugated hydrazone group can generate a binding pocket for Zn2+. These results also demonstrate that 1-hydroxypyrene-2-carboaldehyde can be a unique platform to introduce various ligands for the colorimetric and fluorescent recognition of metal ions.
    Dyes and Pigments 01/2013; 96(1):176–179. · 3.47 Impact Factor
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    ABSTRACT: BACKGROUND: The main problem in performing endoscopic submucosal dissection (ESD) of gastric neoplasms is that it is technically difficult, especially for beginners. METHODS: A total of 51 patients were randomly assigned to undergo transnasal endoscope-assisted or routine ESD performed by two endoscopists inexperienced in ESD while supervised by one expert. RESULTS: Total procedure time (p = 0.330), complete resection rate (p = 0.977), and complication rate (p = 0.157) were similar for the patients who underwent transnasal endoscope-assisted and routine ESD, but bleeding control time was significantly longer in the transnasal endoscope-assisted ESD group (p = 0.002). Three and six patients in the transnasal endoscope-assisted and routine ESD groups, respectively, were "dropped out" during the procedures (p = 0.291). The endoscopists tended to regard the traction with the transnasal endoscope as more useful for large tumors (p = 0.062). Bleeding control in patients who underwent the transnasal endoscope-assisted ESD was significantly longer for patients with tumors located in the anterior wall, posterior wall, and lesser curvature of the stomach (p = 0.001). CONCLUSION: Transnasal endoscope-assisted ESD does not result in improved outcomes when performed by beginners, except for some large tumors. The traction method used by beginners was not superior to proper supervision and advice by an expert during ESD and allowing the expert to perform the procedure when the risk of complications is high or the procedure is delayed.
    Surgical Endoscopy 10/2012; · 3.31 Impact Factor
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    ABSTRACT: A new fluorescent receptor composed of two imidazoliums, two pyrenes and a boronic acid has been synthesized and studied for the recognition of 3,4-dihydroxyphenylacetic acid (DOPAC), which is the metabolite of dopamine. Dopamine, l-DOPA and catechol also induced fluorescence quenching effects, however, 1 displayed a largest association constant with DOPAC. In addition, d-fructose, d-glucose and l-phenylalanine did not show any significant fluorescence change. These fluorescence changes were observed at pH 7.4 in HEPES(0.02 M, pH 7.4)–CH3CN (95:5, v/v). As far as we are aware of, our receptor 1 is the first example of fluorescent chemosensor which shows selectivity for DOPAC. The unique intermolecular excimer formation and fluorescence quenching effects with DOPAC and catechol are carefully explained based on the theoretical calculations.
    Sensors and Actuators B Chemical 10/2012; 176:611. · 3.84 Impact Factor
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    ABSTRACT: BACKGROUND: Reducing food residue by proper preparation methods before endoscopy after distal gastrectomy can increase the quality of examination and decrease patient discomfort. We evaluated the risk factors for food residue and proper methods of preparation for endoscopy after distal gastrectomy. METHODS: Follow-up endoscopy with questionnaires was performed on 1,001 patients who underwent distal gastrectomy at Asan Medical Center between December 2010 and July 2011. RESULTS: Endoscopic examination failed in 94 patients (9.4 %) as a result of large amounts of food residue. Rates of failure were significantly higher in patients who ate a regular diet rather than a soft diet at last dinner before examination (13.9 vs. 6.1 %, p = 0.050), and in those who ate lunch rather than not eating lunch on the day before examination (14.6 vs. 7.7 %, p = 0.020). Multivariate analysis showed that the rate of failed examination was lower in patients who had a history of abdominal surgery (p = 0.011), those who ate a soft (p < 0.001) or liquid (p = 0.003) diet as a last meal rather than a regular diet, those who underwent Billroth I rather than Billroth II reconstruction (p = 0.035), patients with longer fasting time (p = 0.009), and those with a longer gastrectomy-to-endoscopy time interval (p < 0.001). CONCLUSIONS: Patients who undergo follow-up endoscopy after surgery should fast more than 18 h and ingest a soft or liquid diet on the day before examination.
    Surgical Endoscopy 10/2012; · 3.31 Impact Factor

Publication Stats

490 Citations
212.98 Total Impact Points


  • 2014
    • Seoul National University
      Sŏul, Seoul, South Korea
  • 2013–2014
    • Inje University
      Kŭmhae, South Gyeongsang, South Korea
    • MEDIPOST Biomedical Research Institute
      Sŏul, Seoul, South Korea
    • Korea Research Institute of Bioscience and Biotechnology KRIBB
      Anzan, Gyeonggi Province, South Korea
  • 2011–2014
    • Asan Medical Center
      • Department of Gastroenterology
      Sŏul, Seoul, South Korea
  • 2012–2013
    • Ewha Womans University
      • • Department of Chemistry Nano Science
      • • Department of Bioinspired Science
      Seoul, Seoul, South Korea
    • Chonnam National University
      • Department of Infectious Diseases
      Gwangju, Gwangju, South Korea
  • 2010–2013
    • Ulsan University Hospital
      Urusan, Ulsan, South Korea
    • Kwandong University
      Gangneung, Gangwon, South Korea
    • Dankook University
      Eidō, North Chungcheong, South Korea
  • 2009–2013
    • Sungkyunkwan University
      • • Samsung Medical Center
      • • Department of Internal Medicine
      • • Department of Molecular and Cell Biology
      Sŏul, Seoul, South Korea
  • 2010–2011
    • Jeju National University
      • Department of Chemistry
      Tse-tsiu, Jeju, South Korea
  • 2009–2011
    • Catholic University of Daegu
      Kayō, North Gyeongsang, South Korea
  • 2007–2011
    • Sahmyook University
      Sŏul, Seoul, South Korea
  • 2006–2010
    • National Cancer Center Korea
      • • Lung Cancer Branch
      • • Colorectal Cancer Branch
      Kōyō, Gyeonggi Province, South Korea
  • 2008–2009
    • Yeungnam University
      • College of Pharmacy
      Gyeongsan, Gyeongsangbuk-do, South Korea