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Dong Chan Kim,
Dae Won Jun,
Eun Chul Jang,
Sang Heum Kim,
Eun Kyung Kim,
Sang Pyo Lee,
Kang Nyeong Lee, Hang Lak Lee,
Oh Young Lee,
Byung Chul Yoon,
Ho Soon Choi
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ABSTRACT: BACKGROUNDAIMS: It is suggested that the hepatic lipid composition is more important than lipid quantity in the pathogenesis of non-alcoholic steatohepatitis. We examined whether lipoic acid (LA) could alter intrahepatic lipid composition and free cholesterol distribution.
HepG2 cells were cultured with palmitic acid (PA) with and without LA. Apoptosis, changes of the mitochondrial structure, intracellular lipid partitioning, and reactive oxygen species (ROS) activity were measured.
Free fatty acid (FA) increased apoptosis, and LA co-treatment prevented this lipotoxicity (apoptosis in controls vs PA vs PA+LA, 0.5% vs 19.5% vs 1.6%, p<0.05). LA also restored the intracellular mitochondrial DNA copy number (553±33.8 copies vs 291±14.55 copies vs 421±21.05 copies, p<0.05) and reversed the morphological changes induced by PA. In addition, ROS was increased in response to PA and was decreased in response to LA co-treatment (41,382 relative fluorescence unit [RFU] vs 43,646 RFU vs 41,935 RFU, p<0.05). LA co-treatment increased the monounsaturated and polyunsaturated FA concentrations and decreased the total saturated FA fraction. It also prevented the movement of intracellular free cholesterol from the cell membrane to the cytoplasm.
LA opposes free FA-generated lipotoxicity by altering the intracellular lipid composition and free cholesterol distribution.
Gut and liver 03/2013; 7(2):221-7. · 0.83 Impact Factor
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ABSTRACT: BACKGROUND: 5-hydroxytryptamine (5-HT) receptors are upregulated in activated hepatic stellate cells (HSCs), and are therefore thought to play an important role in their activation. AIM: The aim of this study was to determine whether 5-HT(2A) receptor antagonists affect the activation or apoptosis of HSCs in vitro and/or in vivo. METHODS: For the in vitro experiments, the viability, apoptosis and wound healing ability of LX-2 cells were examined after treatment with various 5-HT(2A) receptor antagonists. Levels of HSC activation markers (procollagen type I, α-SMA, TGF-β and Smad 2/3) were measured. For in vivo experiments, rats were divided into three groups: (i) a control group, (ii) a disease group, in which cirrhosis was induced by thioacetamide (iii) a treatment group, in which cirrhosis was induced and a 5-HT(2A) receptor antagonist (sarpogrelate, 30 mg/kg) was administered. RESULTS: 5-HT(2A) , but not 5-HT(2B) receptor mRNA increased with time upon HSC activation. 5-HT(2A) receptor antagonists (ketanserin and sarpogrelate) inhibited viability and wound healing in LX-2 cells and induced apoptosis. Expression of α-SMA and procollagen type I was also inhibited. In the in vivo study, lobular inflammation was reduced in the sarpogrelate-treated group, but there was only slight and statistically insignificant attenuation of periportal fibrosis. Expression of α-SMA, TGF-β and Smad 2/3 was also reduced in the treatment group. CONCLUSIONS: 5-HT(2A) receptor antagonists can reduce inflammation and the activation of HSCs in this cirrhotic model.
Liver international: official journal of the International Association for the Study of the Liver 01/2013; · 3.82 Impact Factor
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Gastroenterology 11/2012; · 11.68 Impact Factor
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ABSTRACT: In Asian countries including Korea, the prevalence of gastroesophageal reflux disease (GERD) is on the rise and its clinical impact has been emphasized. The purpose of this study was to investigate the clinical characteristics of esophagitis patients with or without symptoms, and their association with psychological factors.
Subjects diagnosed as erosive esophagitis of Los Angeles-A or more in screening by upper gastrointestinal endoscopy were enrolled. Questionnaires regarding GERD symptoms and Symptom Checklist-90-Revision were used to identify the presence of psychological symptoms.
There was no difference between the subjects' general characteristics (gender, age, body mass index, smoking and alcohol intake) according to the existence of typical symptoms in these patients with erosive esophagitis. Patients with typical GERD symptoms were more likely to have atypical symptoms, dyspepsia and higher scores on psychological symptoms (somatization, obsessive-compulsiveness and phobic anxiety) than those without.
Psychological symptoms and other gastrointestinal symptoms should be considered in the patients with erosive esophagitis.
Journal of neurogastroenterology and motility 07/2012; 18(3):284-90.
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ABSTRACT: Endoscopic submucosal dissection (ESD) is an effective treatment of early gastric tumors, but submucosal fibrosis can be an obstacle to successful ESD.
To examine the association between endoscopic and pathologic factors and submucosal fibrosis in early gastric tumors, and to measure the association between degree of submucosal fibrosis and outcomes of ESD.
A retrospective study.
An academic medical center.
From November 2006 to April 2011, 161 patients with 167 early gastric tumors treated by ESD.
ESD.
Endoscopic and pathologic factors related to submucosal fibrosis. Procedure time, en bloc resection rate, and complications according to degree of submucosal fibrosis.
In univariate analysis, the presence of endoscopic submucosal fibrosis was significantly related to tumor size, location, ulceration, histologic findings, and submucosal invasion. Multivariate analysis for these factors showed that endoscopic submucosal fibrosis was independently associated with lesions in tumor size greater than 30 mm, in the proximal portion of the stomach, and more common in adenocarcinomas than in adenomas. After correction for multiple testing, only the middle of the stomach as a locational risk factor retains statistical significance. Also, the more advanced the endoscopic submucosal fibrosis, the longer the time required for ESD (P < .0001). The severity of endoscopic submucosal fibrosis was associated with a lower en bloc resection rate and with abundant immediate bleeding.
Retrospective, single-center study.
Submucosal fibrosis of early gastric tumors is closely related to tumor size, location, ulceration, histologic findings, and submucosal invasion. Moreover, the greater the degree of submucosal fibrosis the longer the time taken for the ESD procedure and the higher the frequency of complications such as perforation and immediate bleeding.
Gastrointestinal endoscopy 07/2012; 76(1):59-66. · 6.71 Impact Factor
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ABSTRACT: Background: The widely accepted range of upper limits of normal ALT levels (ULN < 40 U/L) was recently challenged by several reports. And both ALT and AST are commonly used as surrogate marker of liver disease, almost all studies related aminotransferase activity limited to ALT activity. We investigated not only upper limit of normal (ULN) of ALT but also AST activity and to identify factors modulating them in healthy Korean. Methods: A cross-sectional study of 411,240 registered blood donor in all nationwide blood banks belong to the Korean Red Cross were conducted. ULN of ALT and AST was evaluated adjusting their age according to national population census database. 'Decision tree model' was used to identify the affecting factors of ALT & AST and optimal cut-off points of affecting factor. Results: 'ULN of ALT' was 34 U/L in men and 24 U/L in women and 'ULN of AST' was 32 U/L in men and 26 U/L in women in blood donor database. Decision tree analysis showed that ALT levels were mostly influenced by BMI level and its critical two cut-off points were 23.5 and 25.8kg/m(2) , respectively. The most affecting factor of AST was gender. Conclusion: ULN of ALT and AST in Korean were lower than conventional accepted value (< 40 U/L) but higher than recently suggested value (male < 30 U/L and female < 19 U/L). BMI was most determining factor for ALT and gender were most influencing factor for AST activity. © 2012 Journal of Gastroenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd.
Journal of Gastroenterology and Hepatology 04/2012; · 2.87 Impact Factor
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ABSTRACT: Telemedicine is a convenient and efficient tool for remote education in various fields. The telemedicine system can also be used to educate doctors and medical students. The aim of our study was to establish the effectiveness of the telemedical system for use in a live endoscopic multichannel demonstration conference and to test the effectiveness and usefulness of a multicenter-based live endoscopic demonstration through live, interactive, high resolution video transmission using advanced networks and the digital video transport system (DVTS).
This study is a prospective multicenter pilot study. A live demonstration of an endoscopic submucosal dissection (ESD) and an endoscopic retrograde cholangiopancreatography (ERCP) using advanced network technology was performed.
The DVTS successfully transmitted uncompressed, high-resolution, digital lectures with endoscopy video during a multichannel endoscopic live demonstration of ESD and ERCP over multiple advanced networks. The overall satisfaction rating when the endoscopic lecture demonstration was performed by combining DVTS was generally good.
We believe that a multicenter-based live endoscopic demonstration is a very effective conferencing method when using advanced networks and DVTS.
Clinical endoscopy. 03/2012; 45(1):73-7.
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Hang Lak Lee,
Dong Chan Kim,
Sang Pyo Lee,
Kang Nyeong Lee,
Dae Won Jun,
Oh Young Lee,
Dong Soo Han,
Byung Chul Yoon,
Ho Soon Choi,
Joon Soo Hahm,
Ki-Seok Jang
Gastrointestinal endoscopy 12/2011; 76(4):913-5. · 6.71 Impact Factor
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Hang Lak Lee
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ABSTRACT: The comparison between 6th and 7th International Union Against Cancer/American Joint Committee on Cancer Classification for Survival Prognosis of Gastric Cancer (Korean J Gastroenterol 2011;58:258-263).
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 11/2011; 58(5):233-4.
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Dae Won Jun,
Won Kyeong Cho,
Jin Hyun Jun,
Hyuk Jin Kwon,
Ki-Seok Jang,
Hyun-Jeong Kim,
Hye Jun Jeon,
Kang Nyeong Lee, Hang Lak Lee,
Oh Young Lee,
Byung Chul Yoon,
Ho Soon Choi,
Joon Soo Hahm,
Min Ho Lee
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ABSTRACT: Mitochondria are the main sites for fatty acid oxidation and play a central role in lipotoxicity and nonalcoholic steatohepatitis.
We investigated whether carnitine prevents free fatty acid (FFA)-induced lipotoxicity in vitro and in vivo.
HepG2 cells were incubated with FFA, along with carnitine and carnitine complexes. Mitochondrial β-oxidation, transmembrane potential, intracellular ATP levels and changes in mitochondrial copy number and morphology were analysed. Otsuka Long-Evans Tokushima Fatty and Long-Evans Tokushima Otsuka rats were segregated into three experimental groups and fed for 8 weeks with (i) normal chow, (ii) a methionine choline-deficient (MCD) diet or (iii) an L-carnitine-supplemented MCD diet.
Carnitine prevented FFA-induced apoptosis (16% vs. 3%, P < 0.05). FFA treatment resulted in swollen mitochondria with increased inner matrix density and loss of cristae. However, mitochondria co-treated with carnitine had normal ultrastructure. The mitochondrial DNA copy number was higher in the carnitine treatment group than in the palmitic acid treatment group (375 vs. 221 copies, P < 0.05). The carnitine group showed higher mitochondrial β-oxidation than did the control and palmitic acid treatment groups (597 vs. 432 and 395 ccpm, P < 0.05). Carnitine treatment increased the mRNA expression of carnitine palmitoyltransferase 1A and peroxisome proliferator-activated receptor-γ, and carnitine-lipoic acid further augmented the mRNA expression. In the in vivo model, carnitine-treated rats showed lower alanine transaminase levels and lesser lobular inflammation than did the MCD-treated rats.
Carnitine and carnitine-lipoic acid prevent lipotoxicity by increasing mitochondrial β-oxidation and reducing intracellular oxidative stress.
Liver international: official journal of the International Association for the Study of the Liver 10/2011; 31(9):1315-24. · 3.82 Impact Factor
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Jong Heon Jeong, Hang Lak Lee,
Jin Ok Kim,
Hye Jin Tae,
Suk Hyun Jung,
Kang Nyeong Lee,
Dae Won Jun,
Oh Young Lee,
Byung Chul Yoon,
Ho Soon Choi,
Joon Soo Hahm,
Soon Young Song
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ABSTRACT: The aim of this study was to examine the relationship of complications related to diverticulitis and visceral obesity. The study was based on a retrospective case note review conducted at the Hanyang University Hospital. Patients were diagnosed with diverticulitis based on clinical symptoms and abdominal computed tomography (CT) findings and divided into two groups: those admitted with complicated diverticulitis and those with a simple diverticulitis episode. We compared the body mass index (BMI) and degree of visceral obesity, measured by abdominal CT. The study included 140 patients, 87 (62.1%) were simple diverticulitis and 53 (37.9%) were complicated diverticulitis. In the complicated diverticulitis group, 9 (6.4%) cases were recurrent, 29 (20.7%) were perforation or abscess patients, and 28 (20%) were patients with systemic inflammatory response syndrome (SIRS). Of the SIRS patients, 13 were involved in other complication groups. When comparing in the two groups, the complicated diverticulitis group had a significantly higher visceral fat area (128.57 cm(2) vs 102.80 cm(2), P = 0.032) and a higher ratio of visceral fat area/subcutaneous fat area (0.997 vs 0.799, P = 0.014). Visceral obesity is significantly associated with complications of diverticulitis.
Journal of Korean medical science 10/2011; 26(10):1339-43. · 0.84 Impact Factor
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ABSTRACT: Every country has standardized reprocessing guidelines for reducing the risk of microorganism transmission via reusable biopsy forceps. Sterilization is performed either by autoclaving or with the use of ethylene oxide (EO) gas. However, there are no clear standard global recommendations. The aim of this study was to determine whether EO gas or autoclaving is a safer and more effective method for the sterilization of reusable forceps.
This was a prospective study conducted at multiple tertiary referral centers. Seventy reusable biopsy forceps that had been reused at least 20 times each were collected from six endoscopy centers. In all, 61 forceps from five centers were sterilized using EO gas, and the nine forceps from the remaining center were placed in an autoclave. We performed real-time polymerase chain reaction (RT-PCR) for Mycobacterium tuberculosis and hepatitis B virus and performed bacterial cultures on the reusable forceps, which were cut into 2- to 3-cm sections. The forceps were also scanned with an electron microscope (EM) to detect surface damage and contamination.
Escherichia coli bacteria were cultured from 2 of the 61 (3.3%) reusable biopsy forceps sterilized with EO gas. On EM scanning, abundant debris and tissue materials remained on the cup surfaces of the reused biopsy forceps and on their inner wires. No microorganisms were found on the autoclaved forceps.
Sterilization with EO gas may be inadequate because the complicated structure of the forceps may interfere with sterilization. Therefore, for optimum safety, reusable biopsy forceps should be sterilized by autoclaving.
Digestive Diseases and Sciences 09/2011; 57(2):405-12. · 2.12 Impact Factor
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Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 09/2011; 10(2):A24. · 5.64 Impact Factor
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Hang Lak Lee,
Oh Wan Kwon,
Kang Nyeong Lee,
Dae Won Jun,
Chang Soo Eun,
Oh Young Lee,
Yong Chul Jeon,
Dong Soo Han,
Byung Chul Yoon,
Ho Soon Choi,
Joon Soo Hahm,
Seung Sam Paik
Gastrointestinal endoscopy 07/2011; 74(3):693-5. · 6.71 Impact Factor
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ABSTRACT: Primary natural killer (NK) cell like T cell lymphoma of the terminal ileum is extremely rare. It most frequently occurs in the nasal or paranasal areas and less frequently in the skin, the soft tissue, and the gastrointestinal tract. NK/T cell lymphoma involving gastrointestinal tract has characteristic endoscopic features of Inflammatory bowel disease. We herein describe a first case of primary NK/T cell lymphoma misdiagnosed as Behcet's enteritis of the terminal ileum colonoscopically and complicated by cecal bleeding and perforation.
The Korean journal of gastroenterology = Taehan Sohwagi Hakhoe chi 06/2011; 57(6):365-9.
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ABSTRACT: Endoscopic submucosal dissection (ESD) is the most advanced and representative technique in the field of therapeutic endoscopy and has been used for the treatment of gastrointestinal neoplasms, including early gastric cancer. The major difference and advantage of ESD compared to existing endoscopic resection techniques, such as endoscopic mucosal resection (EMR) and polypectomy, are the width and depth of the resection. Newly developed cutting devices, distal attachable endoscopic accessories, and an advanced electrosurgical unit have helped to overcome the limitations of therapeutic endoscopy in terms of lesion size, location, presence of fibrotic scarring, and accompanying ulcers. As a result, the indications for ESD have been expanded from the classical indication for EMR and polypectomy, and there is now support for a further expansion of ESD indications. At present, the most critical factor to consider in the decision of whether to perform ESD is the probability of unexpected lymph node metastasis. The guidelines for ESD are continually being updated and debated. In this review, we discuss the strengths and weaknesses of the expanded guidelines, based on evidence found in the literature.
World Journal of Gastroenterology 06/2011; 17(21):2597-601. · 2.47 Impact Factor
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Gastrointestinal endoscopy 12/2010; 72(6):1267-8; discussion 1268. · 6.71 Impact Factor
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Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 10/2010; 9(3):e20. · 5.64 Impact Factor
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Hang Lak Lee
New England Journal of Medicine 09/2010; 363(12):1163. · 53.30 Impact Factor
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ABSTRACT: Gastroesophageal reflux disease (GERD) is caused by abnormal reflux of gastric contents into the esophagus. GERD can be divided into two groups, erosive esophagitis and non-erosive reflux disease (NERD). The aim of this study was to compare the clinical characteristics of patients with erosive esophagitis to those with NERD. All participating patients underwent an upper endoscopy during a voluntary health check-up. The NERD group consisted of 500 subjects with classic GERD symptoms in the absence of esophageal mucosal injury during upper endoscopy. The erosive esophagitis group consisted of 292 subjects with superficial esophageal erosions with or without typical symptoms of GERD. Among GERD patients, male gender, high body mass index, high obesity degree, high waist-to-hip ratio, high triglycerides, alcohol intake, smoking and the presence of a hiatal hernia were positively related to the development of erosive esophagitis compared to NERD. In multivariated analysis, male gender, waist-to-hip ratio and the presence of a hiatal hernia were the significant risk factors of erosive esophagitis. We suggest that erosive esophagitis was more closely related to abdominal obesity.
Journal of Korean medical science 09/2010; 25(9):1318-22. · 0.84 Impact Factor
