O-GlcNAcylation of amyloid-β precursor protein at threonine 576 residue regulates trafficking and processing

Chun, Y.S.,Kwon, O.H.,Chung, S. Academic Press 2017 Biochemical and biophysical research communication Vol. No.

The pathological hallmark of Alzheimer's disease (AD) is associated with the accumulation of amyloid-β (Aβ) derived from proteolytic processing of amyloid-β precursor protein (APP). APP undergoes post-translational modification including N- and O-glycosylation. O-GlcNAcylation is a novel type of O-glycosylation, mediated by O-GlcNAc transferase attaching O-β-N-acetylglucosamine (O-GlcNAc) to serine/threonine residues of the target proteins. O-GlcNAc is removed by O-GlcNAcase. We have previously reported that increasing O-GlcNAcylated APP using the O-GlcNAcase inhibitor, PUGNAc, increases its trafficking rate to the plasma membrane and decreases its endocytosis rate, resulting in decreased Aβ production. However, O-GlcNAc modification sites in APP are unknown. In this study, we mutated three predicted O-GlcNAc modification threonine residues of APP into alanines (T291A, T292A, and T576A) and expressed them in HeLa cells. These APP mutants showed reduced O-GlcNAcylation levels, indicating that these sites were endogenously O-GlcNAcylated. Thr 576 was the major O-GlcNAcylation site when cell was treated with PUGNAc. We also showed that the effects of PUGNAc on APP trafficking to the plasma membrane and Aβ production were prevented in the T576A mutant. These results implicate Thr 576 as the major O-GlcNAcylation site in APP and indicate that O-GlcNAcylation of this residue regulates its trafficking and processing. Thus, specific O-GlcNAcylation of APP at Thr 576 may be a novel and promising drug target for AD therapeutics.

서울대학교 保健大學院 博士課程 敎育프로그램의 評價的 硏究

정인숙,박태진,김성옥,배은영,박은옥,김정순,문 용 서울大學校保健大學院 1997 國民保健硏究所硏究論叢 Vol.7 No.2

The doctoral program of school of Public Health in Seoul National University was established in 1976 and about 100 students have graduated or completed the course. Even though there have been several studies on evaluating the educational programs of the school, both master's and doctorate's since early 1980s, this study was carried out to identify needs of students, their performance and perceived achievements, unmet needs and barriers in achieving their educational goals only on doctoral graduates. The study was done by the students of doctoral program taking 'evaluative research in public health services' course as a practice under the direction of the teaching staff. Out of 91 eligibles 51 persons responded to the mail and/or telephone interview, and the results obtained are as followings: 1) The goal of the doctoral program of the Public Health, SNU that was to produce competent public health specialists furnished with full abilities of performong research, education and administration(service)has not been changed since 1976 as was set on the program establishment. 2) The objective of enrollment to the program stated by the subjecs varied considerably; majority of them(47%) for expanding scope of public health sceience, for advanced degree(39%), for contribution to the progress of public health sceience(20%), for better job(20%) and for pure academic interest(2%). 3) The needs of students by area of concern, for instance research, theaching and administration, each classified into several performance is viewed as the proportion accomplished out of needs, which are quantified by 5-point Likert scale, most of the graduates indicated that they have accomplished their needs in 83-92% for research abilities, 75-92% for teaching sbilities and 72-96% for administration abilities, the average performance being the highes in research. 5) The barriers that hindered their performance were the school facilities, such as library(72.5%), deficient funds for research(39.2%), insufficient students' room(33.3%) and deficient laboratory supplies(25.5%). 6) The barrier related to student's characteristics were insufficient study time for part-time student(56.9%), deficient study motivation(45.1%), tendency to take easy curriculum(29.4%) and addmittence of less qualificated students(19.6%). 7) The barrier related to professor's characteristics were deficiency of self-development endeavour(62.7%), lack of professor majoring in some particular fields of public health(39.2%), infrequent collaborative researches/activities with students (17.6%), and absolutely deficient number of professors that are necessary for the program(17.6%). In general, however, the graduates appered to be satisfied in terms of what they have accomplished through the current educational program, which have been revised by the school from time to time to cope with the student's as well as community's demand.

서울대학교 保健大學院 博士課程 敎育프로그램의 評價的 硏究

김정순,김성옥,문용,박은옥,박태진,배은영,정인숙 서울大學校 保健大學院 國民保健硏究所 1997 國民保健硏究所 硏究論叢 Vol.7 No.2

Heme oxygenase-1 mediates nicotine- and lipopolysaccharide-induced expression of cyclooxygenase-2 and inducible nitric oxide synthase in human periodontal ligament cells

Pi, S.-H.,Jeong, G.-S.,Oh, H.-W.,Kim, Y.-S.,Pae, H.-O.,Chung, H.-T.,Lee, S.-K.,Kim, E.-C. Blackwell Publishing Ltd 2010 Journal of periodontal research Vol.45 No.2

<P><I>Pi S-H, Jeong G-S, Oh H-W, Kim Y-S, Pae H-O, Chung H-T, Lee S-K, Kim E-C. Heme oxygenase-1 mediates nicotine- and lipopolysaccharide-induced expression of cyclooxygenase-2 and inducible nitric oxide synthase in human periodontal ligament cells. J Periodont Res 2010; 45: 177–183. © 2010 John Wiley & Sons A/S</I></P><P>Background and Objective: </P><P>Although heme oxygenase-1 (HO-1) plays a key role in inflammation, its anti-inflammatory effects and mechanism of action in periodontitis are still unknown. This study aimed to identify the effects of HO-1 on the proinflammatory mediators activated by nicotine and lipopolysaccharide (LPS) stimulation in human periodontal ligament (PDL) cells.</P><P>Material and Methods: </P><P>The production of nitric oxide (NO) and prostaglandin E<SUB>2</SUB> (PGE<SUB>2</SUB>) was evaluated using Griess reagent and an enzyme immunoassay, respectively. The expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2) and HO-1 proteins was evaluated by Western blot analysis.</P><P>Results: </P><P>Lipopolysaccharide and nicotine synergistically induced the production of NO and PGE<SUB>2</SUB> and increased the protein expression of iNOS, COX-2 and HO-1. Treatment with an HO-1 inhibitor and HO-1 small interfering RNAs blocked the LPS- and nicotine-stimulated NO and PGE<SUB>2</SUB> release as well as the expression of iNOS and COX-2.</P><P>Conclusion: </P><P>Our data suggest that the nicotine- and LPS-induced inflammatory effects on PDL cells may act through a novel mechanism involving the action of HO-1. Thus, HO-1 may provide a potential therapeutic target for the treatment of periodontal disease associated with smoking and dental plaque.</P>

Clinical and histopathological study of Charcot-Marie-Tooth neuropathy with a novel S90W mutation in BSCL2.

Choi, B-O,Park, M-H,Chung, K W,Woo, H-M,Koo, H,Chung, H-K,Choi, K-G,Park, K D,Lee, H J,Hyun, Y S,Koo, S K Oxford University Press 2013 Neurogenetics Vol.14 No.1

<P>The objective of the study was to investigate the disease-causing mutation in an autosomal dominant Charcot-Marie-Tooth disease type 2 family and examine the clinical and histopathological evaluation. We enrolled a family of Korean origin with axonal Charcot-Marie-Tooth disease neuropathy (FC305; 13 males, six females) and applied genome-wide linkage analysis. Whole exome sequencing was performed for two patients. In addition, sural nerve biopsies were obtained from two patients. Through whole exome sequencing, we identified an average of 20,336 coding variants from two patients. We also found evidence of linkage mapped to chromosome 11p11-11q13.3 (LOD score of 3.6). Among these variants in the linkage region, we detected a novel p.S90W mutation in the Berardinelli-Seip congenital lipodystrophy 2 (BSCL2) gene, after filtering 31 Korean control exomes. Our p.S90W patients had frequent sensory disturbances, pyramidal tract signs, and predominant right thenar muscle atrophy in comparison with reported p.S90L patients. The phenotypic spectra were wide and demonstrated intrafamilial variability. Two patients with different clinical features underwent sural nerve biopsies; the myelinated fiber densities were increased slightly in both patients, which differed from two previous case reports of BSCL2 mutations (p.S90L and p.N88S). This report expands the variability of the clinical spectrum associated with the BSCL2 gene and describes the first family with the p.S90W mutation.</P>

장기 저장연료의 열안정성 및 연료접촉 고무오링의 수명예측 연구

정근우(K. W. Chung),홍진숙(J. S. Hong),김영운(Y. W. Kim),한정식(J. S. Han),정병훈(B. H. Jeong),권태수(T. S. Kwon),서동욱(D. O. Suh),성민준(M. J. Sung),권영일(Y. I. Kwon) 한국트라이볼로지학회 2018 한국윤활학회지(윤활학회지) Vol.34 No.5

Thermal deterioration of fuel due to long-term storage influences engine performance and causes malfunctions. Fuel stability is usually evaluated via heat resistance and thermal stability during a brief heat shock at high temperature; storage stability in this scenario means that there is very little change in the quality of the fuel during long-term storage. In addition, rubber-based products such as oil seals, O-rings, and rubber hoses can influence the quality of the fuel. When these rubber products are in contact with fuel, they can swell, mechanically weaken, and occasionally crack, thus leaking low molar weight rubber and additives including plasticizer and antioxidant into the fuel to degrade its properties and shorten its useful lifetime. This study determines the thermal stabilities of three kinds of synthetic fuels by evaluating their low temperature kinematic viscosities, chemical composition changes via GC analyses, gross heat of combustion, and color changes. We evaluate the compression set of O-rings by immersing one NBR and two FKM rubber O-rings in the three synthetic fuel samples in airtight containers at variable storage temperatures for six months; from this, we estimate the lifetimes of the O-rings using the Power law model. There were very little changes in the chemical compositions and gross heat of combustion after six months of the experiment. The lifetimes are thus dependent on the materials of the rubber products, and in particular, the FKM O-ring was calculated to have a theoretical lifetime of 200 to 5,700 years. These results indicate that the synthetic fuels maintain their physical properties even after long-term storage at high temperatures, and the FKM O-ring is suitable for long-term sealing of these fuels.

수도작용 송풍식 입제살포기 개발에 관한 연구 : 입제 배출량, 분두 및 적정살포조건 Granular Discharge Rate, Diffuser and Optimal Application Conditions

정창주,정선옥,장영창,최영수,최중섭 한국농업기계학회 1997 바이오시스템공학 Vol.22 No.2

Down증후군에 대한 세포유전학적 연구

정순오,양재섭 中央醫學社 1976 中央醫學 Vol.30 No.5

The chromosomal studies on the patients who had been initially diagnosed as mental retardation, growth retardation, suspicious Down's syndrome or other genetic anomalies, were performed in the Genetics Laboratory, Yonsei University College of Medicine from January 1, 1974 to March 31, 1976. As a result of that, we present the 15 Down's syndrome karyotpes in this paper. Out of them, 13 cases have possessed the typical Down's syndrome karyptype, i.e., primary trisomy for chromosome 21 (47, XX or XY, -21) and 2 cases have had mosaic patterns (46, XY/47, XY, +21). Not any kinds of translocation of the long arm of chromosome 21 onto either a D chromosome or another G chromosome have been observed. In 2 cases; maternal karyotypes were analyzed but they are found out to be normal chromosomal patterns. One Down's syndrome patient with congenital lukaemia has only trisomy for chromosome 21 but not any other chromosomal abnormality.

Direct Observation of Sequential Weak Decay of a Double Hypernucleus

AOKI, S.,BAHK, S. Y.,CHUNG, K. S.,CHUNG, S. H.,FUNAHASHI, H.,HAHN, C. H.,HARA, T.,HIRATA, S.,HOSHINO, K.,IEIRI, M.,IIJIMA, T.,IMAI, K.,ISHIGAMI, T.,ITOW, Y.,KAZUNO, M.,KIKUCHI, K.,KIM, C. O.,KIM, D. C 國立昌原大學校 基礎科學硏究所 1992 基礎科學硏究所論文集 Vol.3 No.-

We have studied stars in nuclear emulsion due to the capture at rest of the ??? hyperons produced in the(???) reaction. The sequential weak decay of a double hypernucleus(nucleus with S= -2) has been directly observed. The double hypernucleus is assigned as either ???? or ????. This assignment excludes the existence of the H dibaryon lighter than 2203.7±0.7 MeV/c².

Characteristics of FAM-Z01 compared to silica gels in the performance of an adsorption bed

Hong, S.W.,Ahn, S.H.,Chung, J.D.,Bae, K.J.,Cha, D.A.,Kwon, O.K. Pergamon 2016 Applied thermal engineering Vol. No.

This paper investigates the characteristics of ferroaluminophosphate (FAM-Z01) compared to various types of conventional silica gels in the performance of an adsorption bed. FAM-Z01 has high potential to replace silica gel due to some key advantages, including a low heating temperature and high adsorption rate resulting from its S-shaped isotherm. We conducted a performance simulation on a fin-tube type adsorption bed with FAM-Z01/water and silica gel/water working pairs and compared the results in terms of coefficient of performance (COP) and specific cooling power (SCP). In the partial pressure range of typical operating condition for silica gels, there was no advantage with FAM-Z01. However, in the partial pressure range of 0.14<P/P<SUB>0</SUB><0.29, which corresponds to a lower evaporation temperature (15<SUP>o</SUP>C→10<SUP>o</SUP>C) and lower heating temperature (80<SUP>o</SUP>C→70<SUP>o</SUP>C) compared to the typical operating condition for silica gels, the COP of FAM-Z01 was almost similar (3.72% decreased) to that of Type-RD silica gel, while the SCP was significantly increased by 35.0%. This indicates that without a change of system efficiency, FAM-Z01/water has a high cooling capacity with small size as compared to Type-RD silica gel/water. This confirms that the adsorbent FAM-Z01 has a high potential to address one of the adsorption chiller's disadvantages, i.e., system size.