Session L : Protein Structure and Function : IDENTIFICATION AND PURIFICATION OF YOLK PROTEIN GENE ENHANCER BINDING PROTEIN FROM DROSOPHILA MELANOGASTER

Hyeok Choon Kwon,Yun Doo Chung,Kyoung Sang Cho,Chung Choo Lee 생화학분자생물학회(구 한국생화학분자생물학회) 1993 추계학술대회집 Vol.- No.-

Body Weight Gain Is Exaggerated by Diet Type on ad Libitum Feeding

( Hyeok Choon Kwon ),( Seung Kyu Choi ),( Seung Woo Nam ),( David A. Brenner ) 대한간학회 2018 춘·추계 학술대회 (KASL) Vol.2018 No.1

Aims: Obesity raises the risk of morbidity from metabolic syndrome including dyslipidemia, diabetes mellitus and fatty liver disease. Weight loss is associated with lowering the risk of metabolic syndrome. To lose body weight, reduced-calorie diet and increased physical activity are required. We report foz/foz (11- bp truncating deletion in exon 8 of Alms1 gene) mice which has disordered appetite regulation fed with western diet, high fat diet and normal chow ad liblitum showed exaggerated body weight gain according to diet pattern. Methods: 4~5 weeks old foz/foz mice and wild type (WT) littermates were fed with western diet, choline-deficient high fat diet(CD-HFD) and normal chow for 12 weeks, ad liblitum. Every week, food intake and body weight were measured and after 12 weeks, metabolic indices were assessed by evaluating body weight, liver weight, the level of fasting glucose and aminotransferase. Results: Total amount of food intake showed no significant difference among western diet, choline-deficient high fat diet and normal chow in spite of different flavor and taste. Average calorie intake was 35% higher in WD and CD-HFD compared with normal chow. However, body weight gain was 75% higher in WD and 49% higher in CD-HFD. AST was 10 times higher in WD and CD-HFD compared with normal chow. All three groups showed glucose intolerance. Conclusions: To reduce the risk of metabolic syndrome associated with obesity, reduced calorie intake and increased physical activity is mandatory. However, to keep reduced calorie intake is challeged while restriction of food intake only. This finding showed that western diet induced most exaggerated body weight gain and body weight gain is influenced more by diet pattern rather than calori itself. Finally, changing behavioral eating pattern is recommended to keep the reduced body weight and improve NASH.

Basic, HCC basic : PO-21 ; Increased apolipoprotein E in hepatocellular carcinoma

( Hyeok Choon Kwon ),( Seung Woo Nam ),( Jae Youn Cheong ),( Soon Sun Kim ),( Marie Yeo ),( Dong Kyu Kim ),( Sung Won Cho ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.-

Background: Hepatocellular carcinoma (HCC) is one of the most malignant tumors worldwide. The goal of our study was to identify new biomarkers for HCC for early detection and for gaining an improved understanding of hepatocarcinogenesis by performing a comparative proteomic analysis of HCC and adjacent non-tumor tissue. Methods: Pairs of tumor and adjacent non-tumor tissue were obtained from 167 HCC patients after surgical resection at Ajou University Hospital, Korea. We assessed the histopathological features and additional clinical data. Proteomic analysis of tumor and non-tumor tissue revealing differential expression using 2D electrophoresis and MALDI-TOF MS analysis reveals some xenobiotic enzymes and apo E was selected. The associations between the expression of apoE and the clinical and pathological parameters were analyzed using SPSS. Results: One of the xenobiotic enzymes, apoE was significantly increased in tumor tissue compared with surrounding nontumor tissue. Paired T-test showed significant high level of apoE in tumor compared with non-tumor (209.91 vs 87.59, p < .01). Oneway ANOVA revealed that levels of apoE were elevated independently among different Child classes, etiologies, sex and consumption of alcohol. Conclusions: We compared the protein profiles between tumor and non-tumor tissue in HCC patients. This study revealed that apoE was significantly higher in HCC than in non-tumor tissue. The multivariate analysis confirmed apoE was higher in regardless of Child class, etiology, sex and alcohol consumption. ApoE has long been known as plasma lipoproteins responsible for cholesterol transport and metabolism. Plasma apoE is produced mainly in the liver but also in the brain, adrenal glands, kidney, and macrophage and not increased in gene expression and serum level in patients with HCC. Some proteomic studies reports a strong relationship between other cancers and apoE. We suppose that this report add a clue to understand hepatocarcinogenesis from hepatic steatosis to consequently hepatic carcinoma.

Emergence of adefovir-resistant mutants after reversion to YMDD wild-type in lamivudine-resistant patients receiving adefovir monotherapy

Kwon, Hyeok Choon,Cheong, Jae Youn,Cho, Sung Won,Choi, Jae Myoung,Hong, Sun Pyo,Kim, Soo-Ok,Yoo, Wang Don Blackwell Publishing Asia 2009 Journal of gastroenterology and hepatology Vol.24 No.1

<P>Abstract</P><P>Background: </P><P>To evaluate the effect of reversion to YMDD wild-type on emergence of adefovir (ADV)-resistant mutation and antiviral activity of ADV in lamivudine (LAM)- resistant patients.</P><P>Methods: </P><P>We determined YMDD mutations and ADV-resistant mutations before and every 3 months during ADV monotherapy in 33 LAM-resistant patients using the restriction fragment mass polymorphism (RFMP) method.</P><P>Results: </P><P>Reversion to pure YMDD wild-type hepatitis B virus (HBV) occurred in 6% (2/33), 9% (3/33), 20% (4/20) and 35% (6/17) of patients after 12, 24, 36 and 48 weeks, respectively. Five (29%) patients were found to have pure YMDD mutants at 48 weeks of therapy. Among 33 patients, 4 (12%) patients developed ADV-resistant mutations at 48 weeks of therapy. Adefovir-resistant mutants emerged in all patients after reversion to YMDD wild-type HBV. The mean serum HBV reductions, evaluated at 24 weeks of therapy, were not different between patients with and without reversion to YMDD wild-type HBV (−3.1 log<SUB>10</SUB> copies/mL <I>vs</I>−3.4 log<SUB>10</SUB> copies/mL, <I>P</I> > 0.05).</P><P>Conclusions: </P><P>ADV-resistant mutations emerged after reversion to YMDD wild-type in LAM-resistant patients who received ADV monotherapy. Thus, ADV add-on therapy may be necessary to reduce the incidence of developing ADV resistance in patients with LAM resistance.</P>

Basic, HCCbasic : PO-21 ; Increased apolipoprotein E in hepatocellular carcinoma

( Hyeok Choon Kwon ),( Seung Woo Nam ),( Jae Youn Cheong ),( Soon Sun Kim ),( Marie Yeo ),( Dong Kyu Kim ),( Sung Won Cho ) 대한간학회 2012 춘·추계 학술대회 (KASL) Vol.2012 No.1

Background: Hepatocellular carcinoma (HCC) is one of the most malignant tumors worldwide. The goal of our study was to identify new biomarkers for HCC for early detection and for gaining an improved understanding of hepatocarcinogenesis by performing a comparative proteomic analysis of HCC and adjacent non-tumor tissue. Methods: Pairs of tumor and adjacent non-tumor tissue were obtained from 167 HCC patients after surgical resection at Ajou University Hospital, Korea. We assessed the histopathological features and additional clinical data. Proteomic analysis of tumor and non-tumor tissue revealing differential expression using 2D electrophoresis and MALDI-TOF MS analysis reveals some xenobiotic enzymes and apo E was selected. The associations between the expression of apoE and the clinical and pathological parameters were analyzed using SPSS. Results: One of the xenobiotic enzymes, apoE was significantly increased in tumor tissue compared with surrounding nontumor tissue. Paired T-test showed significant high level of apoE in tumor compared with non-tumor (209.91 vs 87.59, p < .01). Oneway ANOVA revealed that levels of apoE were elevated independently among different Child classes, etiologies, sex and consumption of alcohol. Conclusions: We compared the protein profiles between tumor and non-tumor tissue in HCC patients. This study revealed that apoE was significantly higher in HCC than in non-tumor tissue. The multivariate analysis confirmed apoE was higher in regardless of Child class, etiology, sex and alcohol consumption. ApoE has long been known as plasma lipoproteins responsible for cholesterol transport and metabolism. Plasma apoE is produced mainly in the liver but also in the brain, adrenal glands, kidney, and macrophage and not increased in gene expression and serum level in patients with HCC. Some proteomic studies reports a strong relationship between other cancers and apoE. We suppose that this report add a clue to understand hepatocarcinogenesis from hepatic steatosis to consequently hepatic carcinoma.

풍선 확장술과 보툴리눔 독소 주입의 복합 치료로 호전된 격렬형 아칼라시아

권혁춘 ( Hyeok Choon Kwon ),이광재 ( Kwang Jae Lee ),명보현 ( Bo Heon Meong ),정재연 ( Jae Yeon Jung ),함기백 ( Ki Biak Hahm ),김진홍 ( Jin Hong Kim ),조성원 ( Sung Won Cho ) 대한소화기기능성질환·운동학회 2005 Journal of Neurogastroenterology and Motility (JNM Vol.11 No.2

Achalasia is a relatively uncommon primary motility disorder of the esophagus that is characterized by aperistalsis of the esophageal body and incomplete relaxation of the LES upon swallowing Vigorous achalasia is a subset of achalasia that show a higher contraction amplitude, minimal esophageal dilatation, prominent tertiary contractions and a higher incidence of chest pain. There is some debates over vigorous achalasia`s the response to treatment. We report here on a patient with vigorous achalasia, and the patient showed high amplitude simultaneous contractions of the esophageal body with severe chest pain and dysphagia. This patient was successfully treated by combined treatments with pneumatic balloon dilatation and botulinum toxin injection on the esophageal body and the lower esophageal sphincter. (Kor J Neurogastroenterol Motil 2005;11:161-165)

원저 : 한국인 비당뇨 성인에서 대사증후군과 관련된 인슐린 저항성 지표의 기준치

권혁춘 ( Hyeok Choon Kwon ),우성일 ( Seong Ill Woo ),김연경 ( Yeon Kyeong Kim ),안상미 ( Sang Mi Ahn ),송경은 ( Kyoung Eun Song ),정선혜 ( Sun Hye Jung ),김대중 ( Dae Jung Kim ),정윤석 ( Yoon Sok Chung ),이관우 ( Kwan Woo Lee ) 대한비만학회 2005 The Korean journal of obesity Vol.14 No.2

연구배경: 본 연구에서는 한국인 성인에서 대사증후군과 관련된 인슐린 저항성 지표의 기준치에 대해 알아보고자 하였다. 방법: 본 연구는 한국 대사증후군 연구(Korean Metabolic Syndrome Study)의 일환으로 수행되었으며, 30세에서 79세까지 976명(남자 484명과 여자 492명)의 비당뇨 성인을 연구대상으로 하였다. 나이, 성별, 체질량지수를 보정한 후 독립변수로서 공복 인슐린, homeostasis model assessment for insulin resistance (HOMA-IR), quantitative insulin sensitivity check index (QUICKI)의 사분위에 따라 대사증후군 이환에 대한 교차비를 조사하였다. 대사증후군의 이환율이 증가하는 공복 인슐린, HOMA-IP, QUICKI의 기준치를 알기 위해 receiver-operating characteristic (ROC) 분석을 하였다. 결과: 전체 대상자의 상위 사분위에 해당하는 값을 인슐린 저항성으로 볼 때 공복 인슐린이 12.94 μU/mL, HOMA-IP 이 3.04, QUICKI의 하위 사분위에 해당하는 기준치는 0.32였다. 최하위 사분위와 비교하였을 때, 공복 인슐린, HOMA-IR, QUICKI의 최상위 사분위에서 대사증후군의 이환율에 대한 보정 교차비는 각각 1.95(1.26~3.01), 2.27(1.45~3.56), 2.27(1.45~3.56)이었다. ROC 분석에 의하면 대사증후군과 관련된 인슐린 저항성 지표로서 공복 인슐린의 기준치는 10.57 μU/mL (민감도 58.5%, 특이도 66.8%), HOMA-IR의 2.34(민감도 62.8%, 특이도 65.7%), QUICKI의 기준치는 0.33 (민감도 61.2%, 특이도 66.8%)였다 (P<0.001). 결론: 공복 인슐린, HOMA-IP, QUICKI는 한국인 비당뇨 성인에서 인슐린 저항성에 대한 좋은 지표로 활용할 수 있으며, 이 연구를 통해 만들어진 기준치를 한국인 비당뇨 성인에서 인슐린 저항성을 조사하고 대사증후군을, 예측하는데 적용할 수 있을 것으로 사료된다. Objective: We investigated the cutoff values of surrogate measures of insulin resistance for diagnosing metabolic syndrome in Korean adults. Research Design and Methods: This study was conducted as part of the Korean Metabolic Syndrome (KMS) Study. The data from 976 non-diabetic individuals (484 men and 492 women) aged 30~79 years were analyzed. We determined the odds ratios for the prevalence of metabolic syndrome according to the quartiles of fasting insulin, homeostasis model assessment for insulin resistance (HOMA-IR), and quantitative insulin sensitivity check index (QUICKI) as independent variables, while adjusting for age, sex, and body mass index. The areas under the receiver-operating characteristic (ROC) curves for fasting insulin, HOMA-IR, and QUICKI for increased metabolic syndrome were compared, and the cutoff values of fasting insulin, HOMA-IR, and QUICKI were estimated. Results: The cutoff points for defining insulin resistance are a fasting insulin level of 12.94 μU/mL, HOMA-IR=3.04 as the 75th percentile value, and QUICKI = 0.32 as the 25th percentile value. Compared with the lowest quartile, the adjusted odds ratios for the prevalence of metabolic syndrome in the highest quartiles of fasting insulin, HOMA-IR, and QUICKI were 1.95(1.26~3.01), 2.27(1.45~3.56), and 2.27(1.45~3.56), respectively. The respective cutoff values for fasting serum insulin, HOMA-IR, and QUICKI by ROC analysis were 10.57μU/mL (sensitivity 58.5%, specificity 66.8%), 2.34(sensitivity 62.8%, specificity 65.7%), and 0.33(sensitivity 61.2%, specificity 66.8%). Conclusions: Fasting insulin, HOMA-IR, and QUICKI are good surrogate measures of insulin resistance in Korean non-diabetic adults. We suggest that the cutoff values using these simple methods could be applied to evaluate insulin resistance and predict metabolic syndrome in Korean non-diabetic adults.

식도열공 헤르니아가 동반된 위암 환자에서 위아전절제술 1년 후에 발생된 단분절 바렛식도

권혁춘 ( Hyeok Choon Kwon ),이광재 ( Kwang Jae Lee ),김장희 ( Jang Hee Kim ),유준환 ( Jun Hwan Yoo ),최재명 ( Jae Myung Choi ),신성재 ( Sung Jae Sin ),정재연 ( Jae Yeon Chung ),함기백 ( Ki Baik Hahm ),김진홍 ( Jin Hong Kim ),조성 대한소화기기능성질환·운동학회 2006 Journal of Neurogastroenterology and Motility (JNM Vol.12 No.1

Barrett`s esophagus is characterized by replacement of esophageal squamous epithelium with specialized intestinal metaplasia as a consequence of long standing gastro-esophageal reflux. It is a major risk factor for esophageal adenocarcinoma. With regard to the pathogenesis of Barrett`s esophagus other than acid reflux, hiatal hernia and duodenogastroesophageal bile reflux are implicated. According to several previous reports, acid reflux associated with bile reflux has been suggested to be a major risk factor for Barrett`s esophagus. This case study reports a patient with Barrett`s esophagus which developed one year after subtotal gastrectomy with gastroduodenostomy due to gastric cancer. Before the operation, the patient had a hiatal hernia but no Barrett`s esophagus. This case represents a significant model for the development of Barrett`s esophagus when acid reflux is combined with duodenogastroesophageal bile reflux. (Kor J Neurogastroenterol Motil 2006;12:77-80)

Simulation of Blur in Transmitted Image through Transparent Plastic for Transparent OLEDs

Kwon, Hyeok-Jun,Yang, Chang-Mo,Kim, Min-Cheol,Kim, Choon-Woo,Ahn, Ji-Young,Kim, Pu-Reum IEEE 2016 Journal of display technology Vol.12 No.8

<P>Transparent displays have received attention as next-generation displays. When attached to transparent displays, transparent plastics can control transmission of incident lights. They can extend the use of transparent displays to various applications. The transmitted image of the background through the transparent plastic appears blurred due to the light diffusion. Major factors affecting this blurriness include the haze and background distance. In this paper, the degree of blurriness in the transmitted image is modelled by the Gaussian blur kernel. With a small set of measurements from the black-and-white patch, the standard deviations of the Gaussian blur kernel and luminance transition curves can be determined for all of the combinations of the haze and background distance. Experimental results indicate that the proposed method accurately estimates the degree of blurriness.</P>

IPv6 네트워크 계층의 보안성 평가를 위한 평가규칙 표기 언어 및 평가 수행기의 설계

권혁찬 ( Hyeok Chan Kwon ),김상춘 ( Sang Choon Kim ) 한국정보처리학회 2004 정보처리학회논문지 C : 정보통신,정보보안 Vol.11 No.4

Recently, many projects have been actively implementing IPsec on the various Operating Systems for security of IPv6 network. But there is no existing tool that checks the IPsec-based systems, which provide IPsec services, work properly and provide their network security services well in the IPv6 network. In this paper, we design SERDL(Security Evaluation Rule Description Language) and rule execution tool for evaluating security of the IPv6 network, and we provide implementation details. The system is divided into following parts:User Interface part, Rule Execution Module part, DBMS part and agent that gathering information needed for security test.