Chang Mo Moon

Kangbuk Samsung Hospital, Sŏul, Seoul, South Korea

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Publications (54)226.12 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Several recent studies have reported that the early use of infliximab (IFX) improves the prognosis of Crohn's disease (CD). However, no data are available from Asian populations, as the forementioned studies have all been conducted in Western countries. The aim of the current study was to evaluate the impact of early use of IFX on the prognosis of Korean patients with CD.
    Intestinal research. 10/2014; 12(4):281-6.
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    ABSTRACT: Recently, several studies have revealed that diagnostic imaging can result in exposure to harmful levels of ionizing radiation in inflammatory bowel disease patients. However, the extent of radiation exposure in intestinal Behcet disease (BD) patients has not been documented. The aim of this study was to estimate the radiation exposure from abdominal imaging studies in intestinal BD patients.
    Gut and liver. 07/2014; 8(4):380-7.
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    ABSTRACT: Background and AimPrior studies have reported 2-L PEG plus ascorbic acid (PEG + Asc) is an effective alternative to standard 4-L PEG for bowel preparation before colonoscopy, but they are limited due to some confounders. Therefore, we compared the efficacy, patient compliance, satisfaction, and safety of 2-L PEG + Asc versus 4-L PEG for bowel cleansing in optimal preparation strategies. Methods In this prospective, randomized, single-blind trial, consenting outpatients were randomly assigned to one of two arms. All colonoscopies were scheduled in the morning and cleansing solutions were administered as a split-dose regimen. Bowel cleansing efficacy in three different segments was measured on a five-point scale with four-point overall grading. Patients’ opinions of the preparation regimens were obtained by questionnaire. ResultsThere was no significant difference between the 2-L PEG + Asc (159/163; 97.5%) and 4-L PEG (162/164; 98.8%) with respect to the overall success of bowel cleansing (mean difference = – 1.3 [– 4.1 - ∞]). Patient compliance, acceptability, and satisfaction were better in the 2-L PEG + Asc arm than the 4-L PEG arm (P < 0.05). Additionally, the incidence of side-effects was lower in the 2-L PEG + Asc than the 4-L PEG (overall, 57.7% vs. 73.2%, P < 0.05). However, no significant difference was seen in patients’ rating of taste. Conclusions In an optimal preparation setting, 2-L PEG + Asc has equal efficacy as a bowel cleanser prior to colonoscopy as 4-L PEG, with the advantages of better patient compliance, satisfaction, and safety.
    Journal of Gastroenterology and Hepatology 01/2014; · 3.33 Impact Factor
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    ABSTRACT: Background and AimAlthough differences in genetic susceptibility and the clinical features of Crohn's disease (CD) have been reported between Asian and Caucasian patients, the disease course and predictors of CD in Asians remains poorly defined. The study therefore aimed to investigate factors predictive of the clinical outcomes of patients with CD in a Korean population. Methods This retrospective multicenter cohort study included 728 Korean CD patients from 13 university hospitals. The first CD-related surgery or need for immunosuppressive or biological agents were regarded as the clinical outcomes of interest. ResultsA total of 126 (17.3%) CD patients underwent CD-related surgery, while 473 (65.0%) and 196 (26.9%) were prescribed thiopurine drugs and infliximab, respectively. Multivariate Cox regression analysis identified current (hazard ratio [HR] = 1.86; P = 0.018) and former smoking habits (HR = 1.78; P = 0.049), stricturing (HR = 2.24; P < 0.001), and penetrating disease behavior at diagnosis (HR = 3.07; P < 0.001) as independent predictors associated with the first CD-related surgery. With respect to immunosuppressive and biological agents, younger age (< 40 years) (HR = 2.17; P < 0.001 and HR = 2.10; P = 0.006, respectively), ileal involvement (HR = 1.36; P = 0.035 and HR = 2.17; P = 0.006, respectively), and perianal disease (HR = 1.42; P = 0.001 and HR = 1.38; P = 0.038, respectively) at diagnosis were significant predictors for the need of these medications. Conclusions In Korean patients with CD, stricturing, penetrating disease behavior, and smoking habits at the time of diagnosis are independent predictors for CD-related surgery. It was also identified that younger age (< 40 years), ileal involvement, and perianal disease at diagnosis are predictive of a need for immunosuppressive or biological agents.
    Journal of Gastroenterology and Hepatology 01/2014; 29(1). · 3.33 Impact Factor
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    ABSTRACT: Intestinal metaplasia (IM), a premalignant lesion, is associated with an increased risk of gastric cancer. Although estrogen exposure, including tamoxifen, has been studied in correlation with gastric cancer, little has been investigated about its effects on IM. Therefore, we investigated whether chronic tamoxifen use was associated with the risk of IM in human stomach. We evaluated 512 gastric biopsies from 433 female breast cancer patients that underwent endoscopic gastroduodenoscopy (EGD) ≥6 months after breast surgery. Histopathological findings were scored according to the updated Sydney classification. Demographic and clinical characteristics were also included to identify predictive factors for IM. In a multivariate logistic regression analysis, age at EGD (odds ratio [OR], 1.04; P = 0.002), biopsies from antrum (OR 2.08; P < 0.001), and Helicobacter pylori positivity (OR 1.68; P = 0.016) were significantly associated with an increased risk of IM, whereas chronic tamoxifen use (≥3 months) was associated with a decreased risk of IM (OR 0.59; P = 0.025). After stratifying by biopsy site, association between tamoxifen use and IM persisted for corpus (OR 0.42; P = 0.026) but not for antrum (OR 0.74; P = 0.327). In analysis limited to patients with follow-up EGD, chronic tamoxifen use also correlated with improved IM score compared to no tamoxifen use (improved, 77.8 vs. 22.2 %; no change, 65.4 vs. 34.6 %; worsened, 30.0 vs. 70.0 %; P = 0.019). This study suggests that chronic tamoxifen use can decrease the risk of IM in human stomach. The effect of tamoxifen is predominantly observed in the corpus.
    Digestive Diseases and Sciences 12/2013; · 2.26 Impact Factor
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    ABSTRACT: Background/Aims: The purpose of this study was to investigate the clinicopathologic features of double primary cancers of the stomach and colorectum, compared to colorectal cancer alone. Methods: A retrospective analysis was made of 5,288 patients who underwent colorectal cancer surgery between January 2000 and December 2009 at Severance Hospital of Yonsei University. The clinicopathologic features were analyzed between 63 patients of double primary cancers and case-matched 126 patients of colorectal cancer alone. We classified double primary cancers into subgroups as premetachronous, synchronous and postmetachronous gastric cancer to identify differences between the three subgroups also. Results: Double primary cancers group showed 4.3 year-older age, lower BMI, and higher percentage of peritoneal metastasis, compared to colorectal cancer alone group. Overall and colorectal cancer specific survival did not have any significant difference between two groups. In histologic type of gastric cancer, a high percentage of undifferentiated adenocarcinoma (55.6%) and signet ring cell carcinoma (30.2%) were noted. Conclusions: Double primary cancers of the stomach and colorectum had older-age onset, lower BMI and higher metastasis to peritoneum than colorectal cancer alone. Combined gastric cancer consisted of high percentage of undifferentiated and signet ring cell carcinomas. (Korean J Gastroenterol 2013;62:27-32).
    The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 07/2013; 62(1):27-32.
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    ABSTRACT: Cancer stem cells (CSCs) play a pivotal role in cancer relapse or metastasis. We investigated the CSC-suppressing effect of nonsteroidal anti-inflammatory drugs (NSAIDs) and the relevant mechanisms in colorectal cancer (CRC). We measured the effect of NSAIDs on CSC populations in Caco-2 or SW620 cells using colosphere formation and flow cytometric analysis of PROM1 (CD133)(+) CD44(+) cells after indomethacin treatment with/without PGE2 or PPARG antagonist, and examined the effect of indomethacin on transcriptional activity and protein expression of NOTCH/HES1 and PPARG. These effects of indomethacin were also evaluated in a xenograft mouse model. NSAIDs (indomethacin, sulindac, and aspirin), celecoxib, γ-secretase inhibitor, and PPARG agonist significantly decreased the number of colospheres formation compared to controls. In Caco-2 and SW620 cells, compared to controls, PROM1 (CD133)(+) CD44(+) cells were significantly decreased by indomethacin treatment, and increased by 5-FU treatment. This 5-FU-induced increase of PROM1 (CD133)(+) CD44(+) cells was significantly attenuated by combination with indomethacin. This CSC-inhibitory effect of indomethacin was reversed by addition of PGE2 and PPARG antagonist. Indomethacin significantly decreased CBFRE and increased PPRE transcriptional activity and their relative protein expressions. In xenograft mouse experiments using 5-FU-resistant SW620 cells, the 5-FU treatment combined with indomethacin significantly reduced tumor growth, compared to 5-FU alone. In addition, treatment of indomethacin alone or combination of 5-FU and indomethacin decreased the expressions of PROM1 (CD133), CD44, PTGS2 (cyclooxygenase 2) and HES1, and increased PPARG expression. NSAIDs could selectively reduce the colon CSCs and suppress 5-FU-induced increase of CSCs via inhibiting PTGS2 (cyclooxygenase 2) and NOTCH/HES1, and activating PPARG. © 2013 Wiley Periodicals, Inc.
    International Journal of Cancer 07/2013; · 6.20 Impact Factor
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    ABSTRACT: BACKGROUND AND AIM: Recent genomic studies have identified genetic variants in the IL12B gene, which encodes the p40 subunit shared by IL12 and IL23, as susceptibility loci for inflammatory bowel disease (IBD). We aimed to identify additional novel genetic variants in IL12B and investigated whether variants confer susceptibility to the development of Crohn's disease (CD) or ulcerative colitis (UC) in the Korean population. METHODS: To detect single nucleotide polymorphisms (SNPs) in IL12B, direct sequencing of all coding exons, exon-intron boundaries, promoter region and 5' untranslated region (UTR) was performed in 24 randomly selected samples. Selected haplotype-tagging SNPs were subsequently genotyped in 493 IBD patients (245 patients with CD and 248 with UC) and 504 healthy controls. RESULTS: Two haplotype-tagging SNPs (rs2288831 and rs919766) were selected through direct sequencing and were genotyped. Of them, SNP rs2288831 in the IL12B gene was significantly associated with CD susceptibility in allelic association analysis (odds ratio [OR]=1.30; 95% confidence interval [CI], 1.04 to 1.62; P=0.019). This significant association with CD was also observed for a haplotype consisting of SNP rs919766 and rs2288831 (OR=1.29; 95% CI, 1.03 to 1.60; P=0.025). However, none of IL12B SNPs were associated with UC susceptibility. Finally, no specific associations between genetic variants and disease phenotype of CD were identified. CONCLUSIONS: This study is first to identify SNP rs2288831 in the IL12B gene as a susceptible variation for CD. Further studies in other ethnic groups are warranted to validate the association of this genetic variant with IBD.
    Journal of Gastroenterology and Hepatology 04/2013; · 3.33 Impact Factor
  • Hepato-gastroenterology 04/2013; 60(128). · 0.77 Impact Factor
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    ABSTRACT: This study sought to determine the natural course of Crohn's disease (CD) and identify predictors that could indicate responsiveness to corticosteroid (CS) therapy. Patients with active CD who were treated with oral CS at a single institution between August 1994 and February 2008 were retrospectively reviewed. The clinical outcomes at 1 month, 4 months, and 1 year after the treatment, as well as clinical and biochemical parameters at the time of CS initiation, were evaluated. A total of 96 patients with CD were enrolled. In this study, 37 patients achieved complete remission (38.5%), 49 achieved partial remission (51.0%), and 10 (10.4%) showed no response at 1 month after the initiation of CS treatment. At 4 months and 1 year after treatment, 66 (69.5%) and 47 (56.6%) patients showed prolonged response, 22 (23.2%) and 20 (24.1%) showed steroid dependency, and 7 (7.4%) and 16 (19.3%) showed refractoriness, respectively. Nonstricturing and nonpenetrating behaviors and a lower CD activity index demonstrated clinical significance for mid-term or mid- and long-term steroid responses, respectively. The short-term response rate to initial oral CS therapy in CD was considerably high, but responsiveness thereafter showed a tendency to decrease with time. Clinical parameters reflecting mild inflammation were associated with responsiveness after CS treatment.
    Gut and liver 01/2013; 7(1):58-65. · 1.31 Impact Factor
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    ABSTRACT: The association between the types of genomic instability and cancer stem cell (CSC) has not been elucidated. We aimed to investigate the expressions of CSC markers with respect to microsatellite instability (MSI) status in human colorectal cancer (CRC). Immunostainings for CD133, CD44, and CD166, and K-ras mutation analysis were performed on 50 MSI-high (MSI-H), and 50 microsatellite stable (MSS) CRC tissues. In 11 MSS and MSI-H CRC cell lines, CD133 expression and DNA methylation statuses of the CD133 promoter were determined. The proportion of CD133 positive cells and the ability of colosphere formation were compared between HCT116 cells and HCT116 + Chr3 cells (hMLH1-restored HCT116 cells). Immunohistochemistry for CSC markers revealed that high CD133 expression was more frequent in MSS cancers than in MSI-H (P < 0.001, 74.0% vs. 28.0%, respectively), and related with short disease-free survival. Neither CD44 nor CD166 expression differed significantly with respect to MSI status. K-ras mutation showed no association with expressions of CD133, CD44, or CD166. CD133 expression was relatively high in the MSS cell lines compared to those in MSI-H, and showed a reverse correlation with DNA methylation of the CD133 promoter. hMLH1-restored HCT116 cells increased proportions of CD133 positive cells and colosphere forming ability, compared to those in HCT116 cells. In conclusion, high levels of CD133 expression were observed more frequently in MSS CRC than in MSI-H, suggesting that differential expression of colon CSC markers may be linked to tumor characteristics dependent on MSI status. © 2012 Wiley Periodicals, Inc.
    Molecular Carcinogenesis 10/2012; · 4.27 Impact Factor
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    ABSTRACT: Background/Aims: Computer tomographic enterography (CTE) is gaining approval for evaluation of small bowel diseases. However, the diagnostic yields of CTE for diseases other than Crohn's disease have not yet been well elucidated. The aim of the present study was to determine the diagnostic utility of CTE and to ascertain the clinical factors predictive of the positive diagnostic rate in patients with unexplained gastrointestinal symptoms or signs. Methodology: The clinical and radiological data of 193 patients with unexplained gastrointestinal symptoms that had a CTE examination at Severance Hospital between May 2007 and April 2010 were retrospectively analyzed. Results: CTE revealed positive findings that explained the symptoms in 51 of the 193 patients (diagnostic yield 26.4%). Positive findings of diagnosis included cancer (12 patients), Crohn's disease (10), intestinal stricture/obstruction (9), small bowel bleeding (7), colitis (6), intestinal Behcet's disease (4), intestinal tuberculosis (2) and intestinal fistula (1). According to univariate analysis, the positive findings of CTE were significantly associated with higher segmentated neutrophil count (p<0.001), higher erythrocyte sedimentation rate (ESR) (p=0.003), higher C-reactive protein (CRP) level (p=0.008) and lower serum albumin level (p=0.037). Multivariate analysis indicated that elevated CRP level was a significant risk factor for the positive findings of CTE (odds ratio 1.950; 95% CI (1.165-3.265), p=0.011). Conclusions: The results of this study suggest that CTE could be helpful in patients suffering from unexplained gastrointestinal symptoms that cannot be explained by established examinations, especially those with elevated C-reactive protein levels.
    Hepato-gastroenterology 09/2012; 59(118):1869-73. · 0.77 Impact Factor
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    ABSTRACT: Changes in the expression of signal transducer and activator of transcription 4 (STAT4) contribute to the development of a variety of autoimmune diseases including inflammatory bowel diseases (IBDs). Moreover, epigenetic modifications, including DNA methylation, are considered a basis for differentiation of T helper cells and regulation of cytokines. In this study, we investigated the methylation status of STAT4 gene in IBD patients and the associations between its genetic and epigenetic alterations in IBD patients. Blood and colonic mucosa samples were obtained from Korean patients with IBD and healthy controls. Peripheral blood mononuclear cells (PBMCs) were isolated, and total RNA and genomic DNA were isolated from the PBMCs and colon mucosa tissues. The mRNA level and DNA methylation status of the promoter were determined by real-time RT-PCR and pyrosequencing, respectively. The chosen SNPs (rs11889341, rs7574865, rs8179673, rs6752770, rs925847, rs10168266, rs10181656, and rs11685878) were genotyped using the TaqMan nuclease assay. Elevated expression of STAT4 was observed in the colonic mucosa and PBMCs of IBD patients. IBD patients showed a lower degree of methylation of the STAT4 promoter than did the healthy controls. Moreover, a significant correlation between risk alleles and methylation status at -172 of the STAT4 promoter was observed, and mRNA levels of STAT4 in IBD patients were correlated inversely with the T-risk allele (rs7574865). Our data demonstrated that the DNA methylation status of STAT4 is associated with genetic polymorphisms, providing insights into the interactions between genetic and epigenetic aberrances in STAT4 that contribute to the development of IBD.
    Digestive Diseases and Sciences 05/2012; 57(10):2600-7. · 2.26 Impact Factor
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    ABSTRACT: BACKGROUND: Recent European ancestry genome-wide association studies have identified genetic variants of IRGM as significant susceptibility loci for Crohn's disease (CD). Therefore, we investigated whether genetic variants of IRGM confer genetic susceptibility to CD or ulcerative colitis (UC) and evaluated the genotype-phenotype associations in the Korean population. METHODS: This study included 510 inflammatory bowel disease (IBD) patients (253 patients with CD and 257 with UC) and 520 healthy controls in Koreans. Initially, we performed direct sequencing analysis to identify unique IRGM single nucleotide polymorphisms (SNPs). Three selected haplotype-tagging SNPs and one risk locus (rs72553867, rs10065172, rs4958847, and rs12654043) within the IRGM were then genotyped in patients and controls. RESULTS: IRGM SNP rs10065172 was significantly associated with CD susceptibility in terms of allelic frequency (P = 0.004; odds ratio [OR] = 1.42) and genotype frequency (dominant model, P = 0.008; OR = 1.62). We also found a relationship between SNP rs72553867 and CD susceptibility in the analysis of allelic frequency (P = 0.0117; OR = 0.67) and genotype frequency (dominant model, P = 0.002; OR = 0.55). In addition, we observed that the association of CD with rs10065172 became stronger in patients with younger age at diagnosis (≤20 years) or male gender. However, there was no significant association between the four SNPs and UC susceptibility. CONCLUSIONS: This is the first study to identify SNP rs10065172 and rs72553867 in IRGM as principal CD susceptibility loci in an Asian population. (Inflamm Bowel Dis 2012;).
    Inflammatory Bowel Diseases 04/2012; · 5.12 Impact Factor
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    ABSTRACT: Although polymorphisms in IL23R have recently been proposed to predispose to Behcet's disease (BD), associations between IL23R polymorphisms and intestinal BD have yet to be elucidated. We therefore performed a study to evaluate whether IL17A, IL23R, and STAT4 polymorphisms are associated with susceptibility to intestinal BD in the Korean population. Single nucleotide polymorphisms (SNP) in the IL17A, IL23R, and STAT4 genes were analyzed using DNA sequencing, denaturing high performance liquid chromatography, and TaqMan genotyping assays. Individual polymorphism analysis revealed that the TT genotype of IL17A rs8193036 (odds ratio (OR) 2.10, 95% confidence interval (CI) (1.12-3.92), p=0.021), and GG+GT genotype of IL23R rs1884444 (OR 1.92, 95% CI (1.03-3.57), p=0.034) was associated with the development of intestinal BD. When these two genotypes were combined, the risk of BD increased compared to that of patients with no-risk or one-risk genotype (OR 2.21, 95% CI (1.13-4.34), p=0.021). Furthermore, statistically significant gene-gene interactions were observed between G149R in IL23R vs. rs11685878 in STAT4, rs2275913 in IL17A vs. rs7574865 in STAT4, and rs11889341 in STAT4 vs. rs2275913 in IL17A. The haplotypes of IL17A had a positive association with intestinal BD risks, whereas those of IL23R were protective for disease development. Our results indicate that the interaction of specific IL17A, IL23R, and STAT4 SNPs modulate susceptibility to intestinal BD in the Korean population, suggesting that the IL-17/23 axis plays a significant role in disease pathogenesis.
    Life sciences 03/2012; 90(19-20):740-6. · 2.56 Impact Factor
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    ABSTRACT: EMR has emerged as an alternative therapeutic option for selected cases of early colorectal cancer (ECC). However, the factors associated with resectability and curability of EMR for ECC remain unknown. To investigate clinical outcomes and factors related to resectability and curability in ECC cases treated with EMR. Retrospective study. Tertiary-care academic medical center. This study involved all patients in whom EMR was performed for ECC at Severance Hospital between March 1997 and August 2007. A total of 236 cases of ECC occurring in 231 patients (66.2% men) were enrolled. EMR. Curative surgical resection and lymph node dissection were used in cases that were incompletely cured by EMR. Resectability, curability, and recurrence. Complete cure was achieved for 162 lesions (68.6%). Of the remaining 74 cases (31.4%), 69 (29.2%) were incompletely cured, and the other 5 (2.1%) had an undetermined resection status and ultimately required supplementary surgical resection for curative treatment. Location on the right side of the colon, piecemeal resection, and submucosal carcinoma were independently associated with incomplete resection, whereas depressed tumor type was independently related to incomplete cure. Among the ECC cases completely cured by EMR and followed for more than a year (n = 118), local recurrence was observed in one case (0.8%) during the median follow-up period of 39.4 months (range 12.4-123.1 months). Single-center, retrospective study. Our data show that EMR is feasible and could be an effective option for treatment of ECC if the technique is applied with the appropriate indications.
    Gastrointestinal endoscopy 12/2011; 74(6):1337-46. · 6.71 Impact Factor
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    ABSTRACT: Triggering receptor expressed on myeloid cells-1 (TREM-1) has been shown to play a crucial role in the propagation of inflammatory responses. Recent studies have reported that TREM-1 expression is up-regulated in patients with inflammatory bowel disease (IBD). Therefore, we investigated the associations between TREM-1 genetic polymorphisms and IBD development and its phenotypes in the Korean population. Three TREM-1 single nucleotide polymorphisms (SNPs, rs2234237, rs3789205, and rs9471535) were genotyped by Taqman technology on 202 Crohn's disease (CD), 265 ulcerative colitis (UC), 138 with intestinal Behcet's disease (BD), and 234 healthy controls and the relationships between these SNPs and IBD development and phenotypes were evaluated. We found that TREM-1 SNPs are significantly associated with the development of intestinal Behcet's disease (rs9471535: odds ratio [OR]=1.637, P=0.025; rs3789205: OR=1.668, P=0.019; rs2234237: OR=1.691, P=0.016), and in particular with skin involvement (rs9471535: OR=2.723, P=0.009; rs3789205: OR=2.477, P=0.017; rs2234237: OR=2.278, P=0.030) and the risk of azathioprine use (rs9471535: OR=2.722, P=0.021; rs3789205: OR=2.493, P=0.032; rs2234237: OR=2.638, P=0.026). However, TREM-1 SNPs were not significantly associated with the development of Crohn's disease or ulcerative colitis. The results of our study suggest that TREM-1 SNPs may play a significant role in the development of intestinal Behcet's disease and may have modest effects on disease severity.
    Life sciences 08/2011; 89(9-10):289-94. · 2.56 Impact Factor
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    ABSTRACT: To identify the associations of genetic and epigenetic variations in IL-23R and IL-17A with inflammatory bowel diseases (IBD). The promoter and exon regions of IL-23R and IL-17A were analysed in 727 subjects (201 Crohn's disease, 268 ulcerative colitis and 258 healthy controls) using DNA sequencing and denaturing high performance liquid chromatography. Transcription factor binding affinity, IL-17A mRNA expression and methylation of the IL-17A promoter were evaluated in peripheral blood mononuclear cells (PBMC) and Jurkat cells. A case-control analysis showed that development of Crohn's disease is associated with the IL-23R variant G149R (OR 0.32, 95% CI 0.15 to 0.68) and IL-17A variant IVS1+18G>C (OR 10.65, 95% CI 1.32 to 85.89). Ulcerative colitis patients showed an association with IL-23R variants G149R (OR 0.41, 95% CI 0.21 to 0.76), IVS4+17C>T (OR 2.89, 95% CI 1.20 to 6.96) and Q3H (OR 0.61, 95% CI 0.38 to 0.99), and IL-17A variants -737C>T (OR 1.50, 95% CI 1.06 to 2.13), -197G>A (OR 0.63, 95% CI 0.40 to 0.97) and IVS1+18 G>C (OR 8.93, 95% CI 1.12 to 70.99). The -877G, -737T and -444A risk alleles of IL-17A displayed higher binding affinities with the transcription factor complex and higher expression levels of IL-17A transcripts. DNA hypomethylation of the IL-17A promoter was observed in PBMC from IBD patients with a significant inverse correlation between methylation extent of IVS1+17 and IL-17A mRNA level. Finally, Jurkat cells recovered IL-17A mRNA expression after exposure to demethylating agent. The results provide insights into the genetic and epigenetic interactions in the IL-23R/IL-17 axis that are associated with elevated expression of IL-17 and IBD pathogenesis.
    Gut 06/2011; 60(11):1527-36. · 10.73 Impact Factor
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    ABSTRACT: Colonoscopy can detect both early intraluminal recurrence and metachronous neoplasia after colorectal cancer resection. Because colon length and location change after colorectal resection, factors affecting insertion time during colonoscopy also might be altered. The goal of this study was to examine whether colonoscope insertion time differs between left-sided resection and right-sided resection and to identify factors that impact the performance of colonoscopy after colorectal resection. We included consecutive patients who underwent colonoscopy between November 2005 and November 2009 after colorectal resection for colorectal cancer. We classified surgical methods into left-sided resection (left hemicolectomy, low anterior resection, anterior resection, Hartman, and Mile's operation) or right-sided resection (right hemicolectomy) and retrospectively evaluated the colonoscope insertion time. Moreover, we analyzed factors that might affect the insertion time. A total of 1,260 patients underwent colonoscopy after colorectal resection during the study period. Of these, 1,248 patients (771 men) who underwent complete colonoscopy were evaluated in this study. The colonoscopy completion rate was 99%, and the mean insertion time was 6.5±5.1 min (median, 5 min; range, 0.3-61 min). Right-sided resection, female gender, poor quality of bowel preparation, lower endoscopist case volume, open laparotomy, and colonoscopy performed more than 1 year after colorectal resection were found to be independent factors associated with prolonged insertion time. This large study identified six factors that affect colonoscope insertion time after colorectal resection. These findings have implications for the practice and teaching of colonoscopy after colorectal resection.
    Surgical Endoscopy 02/2011; 25(7):2316-22. · 3.43 Impact Factor
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    ABSTRACT: Silent gastroesophageal reflux disease (GERD) is often detected during routine screening esophagogastroduodenoscopy (EGD). However, the risk factors and clinical implications of silent GERD remain unclear. In the present study, we investigated the risk factors for asymptomatic erosive esophagitis by analyzing the local area health examination data. The Korean National Health Insurance Corporation provides a bi-annual health examination performed by qualified local hospitals for the early detection of cancer in medical insurance holders over 40 years of age. Participants who completed self-reported questionnaires on health, followed by EGD at the Myongji Hospital (Goyang, Korea), were enrolled in this study. The data of a total of 5301 participants who underwent EGD between January 2005 and December 2008 were analyzed. The prevalence of erosive esophagitis was 6%. In the multivariate analysis, erosive esophagitis was strongly associated with an age greater than 60 years (odds ratio [OR]: 0.7, 95% confidence interval [CI]: 0.6-1.0), male sex (OR: 2.3, 95% CI: 1.7-3.0), hiatus hernia (OR: 2.9, 95% CI: 2.1-4.0), duodenal ulcer (OR: 1.6, 95% CI: 1.1-2.5), hypertension (OR: 1.5, 95% CI: 1.2-2.0), and smoking (OR: 1.4, 95% CI: 1.0-1.8). Of the 320 participants with erosive esophagitis, 145 (45.3%) were asymptomatic participants, and those who were more frequently greater than 60 years (OR: 1.8, 95% CI: 1.1-3.1) and male (OR: 1.8, 95% CI: 1.1-3.2). Asymptomatic erosive esophagitis in adults older than 40 years is strongly associated with old age (≥ 60 years) and male sex compared with symptomatic erosive esophagitis.
    Journal of Gastroenterology and Hepatology 02/2011; 26(6):1034-8. · 3.33 Impact Factor

Publication Stats

248 Citations
226.12 Total Impact Points

Institutions

  • 2013–2014
    • Kangbuk Samsung Hospital
      Sŏul, Seoul, South Korea
  • 2005–2013
    • Yonsei University Hospital
      • Department of Internal Medicine
      Seoul, Seoul, South Korea
  • 2011
    • Kyung Hee University
      Sŏul, Seoul, South Korea
    • Myongji Hospital
      Kōyō, Gyeonggi Province, South Korea
  • 2010
    • Keimyung University
      Sŏul, Seoul, South Korea