Sung Noh Hong - Academia.edu (original) (raw)

Papers by Sung Noh Hong

Intestinal Research

Crohn’s disease (CD) is a relapsing and progressive condition characterized by diarrhea, abdomina... more Crohn’s disease (CD) is a relapsing and progressive condition characterized by diarrhea, abdominal pain, weight loss, and hematochezia that results in serious complications such as perforations, fistulas, and abscesses. Various medications, interventions, and surgical treatments have been used to treat CD. The Korean guidelines for CD management were distributed in 2012 and revised in 2017 by the Inflammatory Bowel Disease (IBD) Research Group of the Korean Association for the Study of Intestinal Diseases. Substantial progress in mucosal immunologic research has elucidated the pathophysiology of IBD, leading to development of biological agents for treatment of CD. The first developed biologic agent, tumor necrosis factor-α agents, were shown to be efficacious in CD, heralding a new era in management of CD. Subsequently, vedolizumab, a monoclonal antibody against integrin α4β7, and ustekinumab, a human monoclonal antibody that inhibits the common p40 subunit of interleukin-12 and int...

Background: Little is known about the ability of epithelial regeneration and wound healing in pat... more Background: Little is known about the ability of epithelial regeneration and wound healing in patients with inflammatory bowel disease, since the ethical issue of clinical trials and the inherent limitations of tumor-derived epithelial cell lines and animal models. We evaluated the epithelial proliferation and wound healing ability of the patients with Crohn’s disease (CD) using the patient-derived intestinal organoids. Methods: Human intestinal organoids were constructed in a three-dimensional intestinal crypt culture of enteroscopic biopsy samples from controls and CD patients. The epithelial regeneration ability of intestinal organoids was assessed using organoid reconstitution, 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT), 5-ethynyl-2′-deoxyuridine (EdU), and wound healing assays. Tumor necrosis factor-alpha (TNFa) is a major pro-inflammatory effector during the CD pathogenesis. Under the TNFa-enriched conditions, the epithelial regeneration ability of CD pa...

Microorganisms, 2020

This study investigated changes in the intestinal microbiota during 8-week infliximab maintenance... more This study investigated changes in the intestinal microbiota during 8-week infliximab maintenance therapy in inflammatory bowel disease (IBD) patients in clinical remission. Microbial compositional differences were analyzed according to the trough level of infliximab (TLI) and mucosal healing (MH) status. 16S rRNA gene-based microbiome profiling was performed on 10 and 74 fecal samples from 10 healthy volunteers and 40 adult IBD patients, respectively. Fecal sampling occurred at 1–2 weeks (1W) and 7–8 weeks (7W) after infliximab infusion. TLI was measured by ELISA at 8 weeks, immediately before the subsequent infusion; MH was evaluated by endoscopy within 3 months. There were no significant changes in microbial composition, species richness, or diversity indices between 1W and 7W. However, 7W samples from the patients with TLI ≥ 5 μg/mL showed an increased species richness compared with patients with TLI < 5 μg/mL, and patients with MH showed increased diversity compared with non...

Gut and Liver, 2020

Background/Aims: Although balloon-assisted enteroscopy (BAE) enables endoscopic visualization of ... more Background/Aims: Although balloon-assisted enteroscopy (BAE) enables endoscopic visualization of small bowel (SB) involvement in Crohn's disease (CD), there is no data on the changes in outcomes over time. We therefore investigated the changes in BAE use on CD patients over different time periods in terms of its role and clinical outcomes. Methods: We used a multicenter enteroscopy database to identify CD patients with SB involvement who underwent BAE (131 procedures, 116 patients). We compared BAE-related factors and outcomes between the first period (70 procedures, 60 patients) and the second period (61 procedures, 56 patients). The specific cutoff point for dividing the two periods was 2007, when BAE guidelines were introduced. Results: Initial diagnosis of SB involvement in CD was the most common indication for BAE during each period (50.0% vs 31.1%, p=0.034). The largest change was in the number of BAE uses for stricture evaluation and/or treatment, which increased significantly in the latter period (2.9% vs 21.3%, p=0.002). The diagnostic yield in patients with suspected CD was 90.7% in the first period and 95.0% in the second (p=0.695). More endoscopic interventions were performed in the second period than in the first (5.1% vs 17.6%, p=0.041). Enteroscopic success rates were high throughout (100% in the first period vs 80.0% in the second period, p>0.999). In the first and second periods, therapeutic plans were adjusted in 62.7% and 61.4% of patients, respectively. Conclusions: The overall clinical indications, outcomes, and effectiveness of BAE were constant over time in CD patients with SB involvement, with the exception that the frequency of enteroscopic intervention increased remarkably. (Gut Liver 2021;15:375-382)

United European Gastroenterology Journal, 2018

BackgroundWhether the etiology of potential small‐bowel bleeding depends on the age and gender of... more BackgroundWhether the etiology of potential small‐bowel bleeding depends on the age and gender of the patient is not yet fully understood.MethodsA total of 1953 patients who underwent video capsule endoscopy (VCE) to evaluate potential small‐bowel bleeding and were registered in the Capsule Endoscopy Nationwide Database Registry from 2003 to 2014 were eligible for this study. VCE findings and the etiology of small‐bowel bleeding were analyzed by age and gender.ResultsThe diagnostic yield of VCE was 48.4% (95% CI: 46.2%–50.6%) and the diagnosis rate of etiology of potential small‐bowel bleeding was 61.4% (95% CI: 59.2%–63.6%). The etiology of potential small‐bowel bleeding depends on the age and gender of the patient. Crohn's disease and small‐bowel diverticular diseases were more prevalent etiology of potential small‐bowel bleeding in the young adults group (< 40 years) whereas angiodysplasia was revealed to be a most common etiology in elderly group (≥ 60 years), reaching st...

Gut and Liver, 2018

Background/Aims: The quality of bowel preparation is important for optimal colonoscopy. It is inf... more Background/Aims: The quality of bowel preparation is important for optimal colonoscopy. It is influenced by medical and personal factors. We aimed to evaluate the effect of bowel habit on the quality of bowel preparation and to identify predictors of inadequate bowel preparation among bowel habit factors. Methods: From June 2017 to September 2017, 90 volunteers were enrolled in this study. Each participant answered a questionnaire consisting of multiple questions about personal bowel habits, including stool form, frequency of bowel movements per week, duration, and degree of straining for bowel movement. Then, all volunteers underwent colonoscopic exam. Eleven endoscopists performed colonoscopies and used the Boston Bowel Preparation Scale (BBPS) as the index for bowel preparation. Two expert endoscopists simultaneously reviewed all colonoscopic images to confirm the final BBPS. Univariate and multivariate logistic regression analyses were performed to verify the correlation between bowel preparation adequacy and bowel habit. Results: Among the 90 participants, 20 (22.2%) had inadequate bowel preparation (total BBPS ≤6 or any segmental BBPS ≤1). In univariate analysis, infrequent bowel movement (0-2/week) (odds ratio [OR], 12.60; 95% confidence interval [CI], 1.22 to 129, p=0.03) and moderate straining (more than 1/4 of defecations) (OR, 4.40; 95% CI, 1.44 to 13.39; p=0.01) were significantly associated with inadequate bowel preparation. However, only moderate straining was significantly associated with inadequate bowel preparation in multivariate analysis (OR, 3.99; 95% CI, 1.26 to 12.65; p=0.02). Conclusions: Straining is a significant predictor for inadequate bowel preparation. For patients with straining during bowel movements, an intensified preparation regimen should be considered.

Intestinal research, 2017

The indications for colorectal endoscopic submucosal dissection (ESD) vary in clinical practice. ... more The indications for colorectal endoscopic submucosal dissection (ESD) vary in clinical practice. To establish colorectal ESD as a standard treatment, standard indications are essential. For establishing standard indications for colorectal ESD, we surveyed the preferences and criteria of endoscopists for colorectal ESD in their practices. A multiple-choice questionnaire was sent to 27 members of the Korean Society of Gastrointestinal Endoscopy/ESD group. The indications of endoscopists for selecting ESD as a treatment for colorectal tumors ≥2 cm in diameter were surveyed. On the basis of the preprocedural assessment of histology, adenoma with high-grade dysplasia, mucosal cancer, and shallow submucosa invasive cancer were included in the indication for ESD. Based on gross morphology, laterally spreading tumor (LST) granular nodular mixed type, LST-nongranular (LST-NG) flat elevated type, and LST-NG pseudodepressed type were included. On the basis of the pit pattern by Kudo classifica...

Gut and liver, Jan 26, 2017

Gastric cancer evolves in the pathologic mucosal milieu, and its development is characterized by ... more Gastric cancer evolves in the pathologic mucosal milieu, and its development is characterized by both the loss of acid-secreting parietal cells and mucosal cell metaplasia, called spasmolytic polypeptide-expressing metaplasia (SPEM). Cytokines, such as interleukin (IL)-10, IL-1β, and IL-6, play a key role in gastric carcinogenesis. However, changes in the cytokine profile of SPEM have not been evaluated. To induce SPEM in mouse stomachs, C57BL/6 mice were intraperitoneally injected with tamoxifen and sacrificed at 3, 10, and 21 days after treatment. RNA-sequencing (RNA-seq) and a multiplex bead array were used to measure cytokines in the stomachs of tamoxifen-treated/control mice. The administration of tamoxifen led to the rapid development and histological normalization of SPEM 3 and 10 days after administration, respectively. RNA-seq revealed that the expression of IL-10 was decreased 3 days after tamoxifen administration. The multiplex assay identified a significant decline in IL...

Inflammatory bowel diseases, Jul 1, 2017

Aberrant gene expression in the gut mucosa might contribute to the initiation and progression of ... more Aberrant gene expression in the gut mucosa might contribute to the initiation and progression of Crohn's disease (CD). RNA sequencing (RNA-seq) provides precise measurements of expression levels of transcripts and their isoforms. The aim of this study was to use RNA-seq to investigate transcriptomic differences and identify significantly differentially expressed transcripts in inflamed and noninflamed intestinal mucosa of CD patients. RNA-seq was performed on 13 pairs of inflamed and noninflamed intestinal mucosa from 13 CD patients and on sex-matched normal mucosa of 13 healthy controls. Significantly differentially expressed transcripts were validated by immunohistochemistry, quantitative reverse transcriptase polymerase chain reaction, and enzyme-linked immunosorbent assay. RNA-seq revealed genome-wide transcriptomic differences between normal mucosa, noninflamed, and inflamed CD mucosa. Among 950 differentially expressed genes, 19 were up- or downregulated (upregulation: ANG...

Gut and liver, Jan 11, 2017

Studies concerning the efficacy and safety of single-balloon enteroscopy (SBE) compared with that... more Studies concerning the efficacy and safety of single-balloon enteroscopy (SBE) compared with that of double-balloon enteroscopy (DBE) often appear to be conflicting. However, previous studies were performed by endoscopists who were less experienced in SBE compared with DBE. We performed a retrospective analysis of SBE and DBE data performed by a single enteroscopist, with expertise in SBE, using a prospective balloon-assisted enteroscopy registry from 2013 to 2015. Furthermore, we performed a comprehensive literature search and meta-analysis of available studies, including the current study, to clarify the efficacy and safety of SBE versus DBE. A total of 65 procedures in 44 patients with SBE and 74 procedures in 69 patients with DBE were analyzed. There were no significant differences in diagnostic yield (61.1% vs 77.3%, respectively, p=0.397), therapeutic yield (39.1% vs 31.8%, respectively, p=0.548), and complication rate (4.4% vs 2.3%, p=1.000). In the meta-analysis, which inclu...

Inflammatory bowel diseases, Jul 13, 2017

A considerable number of patients with Crohn's disease (CD) develop irreversible intestinal d... more A considerable number of patients with Crohn's disease (CD) develop irreversible intestinal damage, although the early administration of immunomodulatory or biological therapies might prevent this. The aims of our study were to develop and validate a novel predictive model that can be used to predict the risk of surgical intervention in Korean patients with CD. The prognostic model was derived from the multicenter longitudinal CONNECT (CrOhn's disease cliNical NEtwork and CohorT) study cohort consisting of 1338 patients with CD, who were split into training and validation sets. The Korean Crohn's Disease Prediction (KCDP) model was developed with the training set data using the Cox proportional hazards model and multivariate analysis, and was then validated using the validation set. A total of 1271 patients with CD were analyzed. During the follow-up period of 10,188 patient-years (median 7.1 yrs), 361 patients (28.4%) underwent CD-related surgery. Age at diagnosis, jeju...

PloS one, 2016

Various modalities have been used to diagnose Meckel's diverticulum (MD) in practice, but wit... more Various modalities have been used to diagnose Meckel's diverticulum (MD) in practice, but with their diagnostic accuracy deemed to be unsatisfactory for clinical practice. Moreover, the usefulness of these modalities has not been evaluated for the diagnosis of bleeding MD in adults, due to the relative rarity of this condition. Therefore, the aim of our multicenter study was to determine the most accurate modality for the preoperative diagnosis of bleeding MD in adults. We conducted a retrospective analysis of the diagnostic accuracy for small bowel bleeding associated with MD of different modalities in patients ≥18 years old who underwent assessment for MD, with confirmation at the time of explorative surgery. Diagnostic accuracy of the different modalities was evaluated against the diagnosis obtained using technetium-99m pertechnetate scintigraphy (also known as Meckel's scan), considered to be the gold standard for the diagnosis of bleeding MD in pediatrics. Thirty-five a...

Obesity (Silver Spring, Md.), Sep 30, 2016

This study examined whether the metabolically healthy obesity (MHO) phenotype was associated with... more This study examined whether the metabolically healthy obesity (MHO) phenotype was associated with an increased risk of diabetes in a large cohort of metabolically healthy individuals and whether that association differed by presence of nonalcoholic fatty liver disease (NAFLD). The cohort consisted of 74,509 Korean adults who were metabolically healthy at baseline, defined as not having any metabolic syndrome component except large waist circumference and having homeostasis model assessment of insulin resistance <2.5. NAFLD was defined as hepatic steatosis on ultrasonography in the absence of excessive alcohol use or any other identifiable cause. Over 304,852.6 person-years of follow-up, 472 participants developed diabetes (incidence density, 1.5 per 1,000 person-years). The multivariable-adjusted hazard ratios (95% confidence intervals) for incident diabetes in subjects with overweight and obesity compared with subjects with normal weight were 1.29 (1.00-2.16) and 1.57 (1.14-2.16...

Gut and liver, Jan 13, 2016

Intestinal tuberculosis (ITB) remains prevalent in Asia. An INF-γ assay (QuantiFERON-TB gold test... more Intestinal tuberculosis (ITB) remains prevalent in Asia. An INF-γ assay (QuantiFERON-TB gold test [QFT]) is considered to be an effective supplementary tool for diagnosing ITB. We retrospectively analyzed the clinical features of ITB patients based on the initial results of QFT. A total of 109 patients with ITB were enrolled, and 82 patients (75.2%) showed positive QFT results. In the QFT-positive group, the mean age (44.1±12.0 years) was significantly higher than that in the QFT-negative group (37.0±14.8, p=0.0096). Abdominal pain (p=0.006) and diarrhea (p=0.030) were more frequent in the QFT-negative group. Further, C-reactive protein (CRP) levels were significantly higher in the QFT-negative group (6.4±9.9 mg/dL) than in the QFT-positive group (1.3±2.3, p<0.001). Multivariate analysis confirmed that younger age (p=0.016), diarrhea (p=0.042), and high levels of CRP (p=0.029) were independent predictors of QFT-negative results in patients with ITB. These results suggest that pri...

Gastroenterology Research and Practice, 2015

Background. We aimed to evaluate the efficacy of various diagnostic tools such as computerized to... more Background. We aimed to evaluate the efficacy of various diagnostic tools such as computerized tomography (CT), small bowel follow-through (SBFT), and capsule endoscopy (CE) in diagnosing small bowel tumors (SBTs). Additionally, we aimed to evaluate the clinical features of SBTs missed by CE. Methods. We retrospectively studied 79 patients with histologically proven SBT. Clinical data were analyzed with particular attention to the efficacy of CT, SBFT, and CE in detecting SBT preoperatively. We also analyzed the clinical features of SBTs missed by CE. Results. The most common symptoms of SBT were bleeding (43%) and abdominal pain (13.9%). Diagnostic yields were as follows: CT detected 55.8% of proven SBTs; SBFT, 46.1%; and CE, 83.3%. The sensitivity for detecting SBTs was 40.4% for CT, 43.9% for SBFT, and 79.6% for CE. Two patients with nondiagnostic but suspicious findings on CE and seven patients with negative findings on CE were eventually found to have SBT. These nine patients w...

Gut and liver, Jan 13, 2015

Colorectal adenomas that are ≥10 mm have villous histology or high-grade dysplasia, or that are a... more Colorectal adenomas that are ≥10 mm have villous histology or high-grade dysplasia, or that are associated with ≥3 adenomas are considered high-risk for metachronous advanced neoplasia. We evaluated the cumulative incidence of metachronous advanced neoplasia according to the total number of high-risk findings detected on baseline colonoscopy. This was a retrospective cohort study performed in 862 patients who underwent removal of colorectal adenomas between 2005-2009. At least one surveillance colonoscopy had been conducted at Konkuk University Medical Center, Seoul, Korea. The cumulative incidence of metachronous advanced neoplasia in patients with 0, 1, 2, and 3-4 high-risk findings at 1 year were 0.7%, 1.3%, 2.8%, and 8.0%; at 3 years, those were 5.9%, 11.9%, 15.5%, and 24.7%; and at 5 years, those were 8.5%, 18.7%, 26.3%, and 37.2%, respectively. In a multivariate model, the risk of metachronous advanced neoplasia was significantly higher for the multiple high-risk findings grou...

Intestinal Research, 2012

There are indirect evidences to suggest that 80% of colorectal cancers (CRC) develop from adenoma... more There are indirect evidences to suggest that 80% of colorectal cancers (CRC) develop from adenomatous polyps and that, on average, it takes 10 years for a small polyp to transform into invasive CRC. In multiple cohort studies, colonoscopic polypectomy has been shown to significantly reduce the expected incidence of CRC by 76% to 90%. Colonoscopic polypectomy is performed frequently in primary outpatient clinics and secondary and tertiary medical centers in Korea. However, there are no evidence-based, procedural guidelines for the appropriate performance of this procedure, including the technical aspects. For the guideline presented here, PubMed, Medline, and Cochrane Library literature searches were performed. When little or no data from well-designed prospective trials were available, an emphasis was placed on the results from large series and reports from recognized experts. Thus, these guidelines for colonoscopic polypectomy are based on a critical review of the available data as well as expert consensus. Further controlled clinical studies are needed to clarify aspects of this statement, and revision may be necessary as new data become available. This guideline is intended to be an educational device to provide information that may assist endoscopists in providing care to patients. This guideline is not a rule and should not be construed as a legal standard of care or as encouraging, advocating, requiring, or discouraging any particular treatment. Clinical decisions for any particular case involve a complex analysis of the patient's condition and the available courses of action. (Intest Res 2012;10:110-124)

Genomics & Informatics, 2013

A radioresistant cell line was established by fractionated ionizing radiation (IR) and assessed b... more A radioresistant cell line was established by fractionated ionizing radiation (IR) and assessed by a clonogenic assay, flow cytometry, and Western blot analysis, as well as zymography and a wound healing assay. Microarray was performed to profile global expression and to search for differentially expressed genes (DEGs) in response to IR. H460R cells demonstrated increased cell scattering and acidic vesicular organelles compared with parental cells. Concomitantly, H460R cells showed characteristics of increased migration and matrix metalloproteinase activity. In addition, H460R cells were resistant to IR, exhibiting reduced expression levels of ionizing responsive proteins (p-p53 and γ-H2AX); apoptosis-related molecules, such as cleaved poly(ADP ribose) polymerase; and endoplasmic reticulum stress-related molecules, such as glucose-regulated protein (GRP78) and C/EBP-homologous protein compared with parental cells, whereas the expression of anti-apoptotic X-linked inhibitor of apoptosis protein was increased. Among DEGs, syntrophin beta 2 (SNTB2) significantly increased in H460R cells in response to IR. Knockdown of SNTB2 by siRNA was more sensitive than the control after IR exposure in H460, H460R, and H1299 cells. Our study suggests that H460R cells have differential properties, including cell morphology, potential for metastasis, and resistance to IR, compared with parental cells. In addition, SNTB2 may play an important role in radioresistance. H460R cells could be helpful in in vitro systems for elucidating the molecular mechanisms of and discovering drugs to overcome radioresistance in lung cancer therapy.

Korean Journal of Medicine, 2015

The treatment for constipation should be individualized and dependent on the cause, coexisting mo... more The treatment for constipation should be individualized and dependent on the cause, coexisting morbidities, and patient's cognitive status. Although most cases of constipation respond to conservative treatment, including dietary and lifestyle changes, or mild laxatives, some patients still complain of consistent symptoms and need an assessment of defecatory dysfunction. There is insufficient evidence to support the use of enemas in chronic constipation, although many clinicians and patients find them useful and effective for the treatment of fecal impaction when used with other modalities. In addition, suppositories can be considered as an initial trial for the treatment of defecatory dysfunction, since they help to initiate or facilitate rectal evacuation. The routine use of enemas is typically discouraged, especially sodium phosphate enemas, although tap-water enemas seem safe for more regular use. Soapsuds enemas are not recommended due to possible rectal mucosal damage.

Journal of Crohn's & colitis, Jan 16, 2014

No previous large-scale studies have evaluated the prognosis of ulcerative colitis (UC) over a pe... more No previous large-scale studies have evaluated the prognosis of ulcerative colitis (UC) over a period of three decades in a non-Caucasian population. The aims of this study were to update the current information on the natural course of UC in a sizable cohort of Korean patients and to evaluate changes in the treatment paradigms and prognosis of UC over time. We retrospectively analyzed 2,802 Korean UC patients who visited Asan Medical Center. We divided the study subjects into three groups based on the year of diagnosis (cohort 1: 1977-1999; cohort 2: 2000-2006; and cohort 3: 2007-2013). Five-year cumulative probabilities of prescription of azathioprine/6-mercaptopurine and anti-tumor necrosis factor (anti-TNF) agents were 4.1% and 0.0%, respectively, in cohort 1 and 27.9% and 12.7%, respectively, in cohort 3 (P < 0.001). A total of 209 patients (7.5%) underwent colectomy, producing cumulative probabilities of colectomy at 10, 20, and 30 years after diagnosis of 7.8%, 14.2%, and ...