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.

돼지 卵子의 透明帶에 대한 單一클론抗體生産과 그 特性에 關한 硏究

金鐘培,劉永春,金昌圭,權五中,鄭盛元,鄭吉生 건국대학교 동물자원연구센터 1991 動物資源硏究誌 Vol.16 No.-

本 試驗은 單一클론抗體의 강한 特異性과 抗體性質의 不變性을 이용하여 發生學的 側面에서 哺乳動物 卵子의 透明帶의 機能과 構造를 이해하고, 또한 種特異的인 精子 受容體의 存在 및 生化學的 構造를 규명하기 위한 기초연구로서, 돼지 卵子의 透明帶를 免疫原으로 하여 BABL/c 생쥐로부터 單一클론抗體를 생산하고 그 특성을 구명하였던 바 다음과 같은 결과를 얻었다. 1) 3마리의 BABL/c 생쥐(YⅠ, YⅡ, ZI)에 돼지卵子의 透明帶를 免疫化하고, 複合抗體 生成을 확인한 후 생쥐의 脾臟細胞와 Myeloma(SP2/O-Ag14)를 polyethylene glycol를 融合을 실시한 결과 각각 25.8%, 54.5% 그리고 59.7%의 融合效率을 나타내었으며, ELISQ에 의해 陽性反應을 조사한 결과 각각 17.3%, 32.6% 그리고 6.2% 陽性反應 效率을 나타내었다. 2) YI에서 강한 陽性反應을 보인 6개의 well에 대한 cloning을 실시하고 抗體檢證을 행한 결과 20.8% ∼ 48.4%의 Cloning效率과 54.6% ∼ 82%의 陽性反應 效率을 나타내었다. 3) 강한 陽性反應을 나타낸 항체에 대해 sandwich ELISA法에 의해 isotype을 決定하였던바 2E93C(YⅠ), 3E83E7(YⅠ), 4E3(YⅡ)각각 IgG₂b, IgG₂a, IgM으로 확인되었다. 4) Isotype이 決定된 2E93C9(YⅠ), 3E84E7(YⅠ), 4E3(YⅡ)의 세포를 생쥐의 腹腔에 주사하여 얻은 腹水를 indirect ELISA法에 의해 titer를 決定한 결과 모두 1:400,000 이상의 높은 titer를 나타내었다. 5) 處理區로서 單一클론抗體의 腹水와 對照區로서 normal mouse serum이 각각 2%씩 함유된 배양액속에서 난자를 배양한 후 顯徵鏡下에서 관찰했을 때 對照區에서 배양된 난자의 표면은 정상적인 형태를 나타냈으나 處理區에서 배양된 卵子는 표면에 뚜렷한 沈澱層을 형성하였다. 6) 處理區와 對照區 卵子를 Rabbit anti-mouse IgG-FITC가 1% 함유된 배양액속에서 배양하고 洗滌한 후 螢光顯徵鏡下에서 관찰한 바 處理區의 卵子는 透明帶 주위에서 螢光이 나타났으나, 對照區에서는 나타나지 않았다. This study was carried out ot produce and characterize monoclonal antibodies against porcine zona pellucida, and undertaken as a basic study to develop immunocontraceptive vaccine and to investigate the function of zana pellucida in early fertilization process. The results obtained were summarized as follows: 1. Spleen cells of three BALB/C mice(YⅠ, YⅡ and ZI) which were immunized with porcine zona pelucida were fused with myeloma cells(SP2/O-Ag14) by polyethylene glycol. At the result of fusion, fusion efficiency was 25.8 , 54.5% and 59.7% and positive efficiency 17.3%, 32.6% and 6.2%, respectively. 2. Cloning efficiency was shown to be from 20.8% to 48.4% and positive efficiency of them were 54.6% to 82%. 3. Sub-isotypes of three strong positive antibodies, 2E93C(YⅠ), 3E83E7(YⅠ) and 4E3(YⅡ) were determined by sandwich ELISA method and shown to be as IgG2b, IgH2a and IgM, respectively. 4. The titers of three ascitic fluids containing antibodies, 2E93C9(YⅠ), 3E84E7(YⅠ) and 4E3(YⅡ) were determined by indirect ELISA and all of them showed above 1:400,000. 5. The layer of precipitate was observed on the zona incubated with medium containing 2% ascitic fluid of monoclonal antibody while the eggs treated with 2% normal mouse serum did not. 6. Porcine eggs incubated with medium containing 2% ascitic fluid of monoclonal antibody and followed by subsequent incubation with Rabbit anti-mouse IgG-FITC conjugate showed strong fluorescent light on the zona surface while the zona of normal mouse serum-treated eggs did not show fluorescence.

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.

200 GeV/핵자 유황이온과 핵건판핵의 충돌에 의해 생성된 헬륨 파쇄핵의 극한파쇄 연구

김동철,송진섭,윤천실,정성헌,박인곤,김종오,김철수,김태연,이승희,조재희,천병구,김재률,김준원,김태익,박명렬,장한일,임인택 慶尙大學校 기초과학연구소 1992 基礎科學硏究所報 Vol.8 No.-

고에너지 중이온 원자핵과 핵건판의 충돌에서, 200GeV/핵자 유황이온에 의해 생성된 파쇄 헬륨핵(Z=2)의 실험실계의 방출각 분포는 표적핵에 무관한 회귀공식. dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)]로 잘 표현된다. 여기에서 의사신속도 η=-ln[tan(θ/2)]이고, y_b는 실험실계의 입사입자(^32S)의 신속도이다. 이 공식에 의한 적합에서 k=-0.057±0.008로 얻어진다. 즉, 핵건판과 고에너지 중이온의 충돌에서 파쇄 헬륨핵의 exp(η-y_b)의 분포는 "극한파쇄" 현상을 잘 설명하고 있다. The angular distribution of emission angle θ of helium (Z=2) produced in the collisions of incident particles of 200 GeV/nucleon ^32S in nuclear emulsion is well expressed by dN=exp[a+k exp(η-y_b)]d[exp(η-y_b)] where the pseudorapidity is η=-ln[tan(θ/2)], the laboratory system primary rapidity is y_b, and k=-0.057+0.008. The shape of this frequency of occurrence distributions in terms of exp(η-y_b) attests to the validity of the concept of "limiting fragmentation" for helium projectile fragments produced in the projectile fragmentation regions of heavy ion collisions in nuclear emulsion.

평행주차 자동조향 제어시스템 개발

김연수(Y. S. Kim),이대현(D. H. Lee),김용주(Y. J. Kim),정선옥(S. O. Chung),김태형(T. H. Kim),최창현(C. H. Choi) 유공압건설기계학회 2015 유공압건설기계학회 학술대회논문집 Vol.2015 No.10

This research is conducted to develop automatic steering system for unmanned agricultural machine developing, and performance of the system was evaluated by parallel parking of conventional vehicle. The automatic steering system consist MDPS (motor drivven power steering) to control steering, ESC (electronic stability control) to acquire wheel speed, ultrasonic sensor to recognize parking space, and controller to communicate and handle data. Parallel parking process using automatic steering control consist parking space recognition, backward path generation, and steering control for path tracking. To recognize parking space length and width of parking space were measured using ultrasonic sensor and calculated traveling distance. The path for parallel parking was generated based on kinematic model of conventional vehicle, and PI controller was used to control steering angle for path tracking. Parallel parking simulation was conducted to determine minimum speed of steering angle control, because too low speed of steering angle control increase error of vehicle position and too high speed of steering angle control has cause MDPS slip. The result of the simulation was that 500 °/s of control speed was selected as minimum speed of steering angle. In order to evaluate performance of the automatic steering system tests for performance evaluation of parking space recognition, position control of steering angle, parallel parking were conducted. The results of performance evaluation test were that measured area of parking space using ultrasonic sensor was smaller than the actual are in every case and standard error became larger when the speed of the car was faster. The performance of the position control of steering angle was that maximum overshoot increased if the speed and steering angle increased when checking at angles of 60, 120 and 180. Delay time was 0.3 seconds with fix time of 2 seconds was measure and the rate of error was mostly below 1% which showed outstanding performance. However, when measuring at 240 degree, the slip of MDPS occurred which caused no result to show. Parallel parking using automatic steering control was conducted by vehicle speed condition, the results show that the errors on x-axis and y-axis were below 0.54 m and 0.14 m, respectively, and error on steering angle was less than 1°; therefore it is possible that parallel parking using automatic steering control system for conventional vehicle.

F-free Y & Cu 전구용액 적용에 의한 YBCO coated conductors의 MOD 공정 개선

김영국,유재무,정국채,고재웅,조윤숙,허은옥,Kim, Y.K.,Yoo, J.M.,Chung, K.C.,Ko, J.W.,Cho, Y.S.,Heo, E.O. 한국초전도학회 2006 Progress in superconductivity Vol.8 No.1

Total Fluorine content in the precursor solution for MOD processing of YBCO coated conductors can be significantly reduced by synthesizing precursor solution with F-free Y & Cu precursor and Barium trifluoroacetate(TFA). It was shown that crack-free and uniform precursor films were formed after calcinations in humidified oxygen atmosphere. Less than 2 hours are required to finish the calcination process, and XRD measurement shows that $BaF_2,\;CuO,\;and\;Y_2O_3$ are major constituent of calcined precursor films. Film thickness after calcination was measured to be ${\sim}2.8$ um by applying slot-die coating method. In particular, addition of Samarium shows critical current of Ic=226 A/cm-w($Jc=3.4\;MA/cm^2$). Also discussed are recent developments in the reel-to-reel processing using F-free Y & Cu precursor solutions. It is shown that uniform and fast processing route to YBCO coated conductor with high Ic can be provided by employing F-free Y & Cu precursor solutions in MOD process.

UV/TiO2 and UV/TiO2/chemical oxidant processes for the removal of humic acid, Cr and Cu in aqueous TiO2 suspensions

Jung, J. -T.,Choi, J. -Y.,Chung, J.,Lee, Y. -W.,Kim, J. -O. Taylor Francis 2009 Environmental Technology Vol.30 No.3

<P> The objective of this study was to investigate the treatment efficiency of UV/TiO2 and UV/TiO2/chemical oxidant processes for the removal of humic acid and hazardous heavy metals in aqueous TiO2 suspensions. The reaction rate (k) of humic acid and hazardous heavy metals by UV/TiO2 was higher than that of UV illumination alone or TiO2 alone. The removal efficiency for humic acid and Cr(VI) at acid or neutral pH values was higher than that at basic pH values. However, the removal efficiency for Cu(II) at acid pH values was smaller compared with that at neutral or basic pH values. The reaction rate (k) of humic acid and hazardous heavy metals in the TiO2 concentration range of 0.1-0.3 g l-1 increased with increasing TiO2 dosage. However, amounts higher than a TiO2 dosage of 0.3 g l-1 reduced the removal efficiency for humic acid and hazardous heavy metals because of the shielding effect on the UV light penetration in the aqueous solution caused by the presence of excessive amounts of TiO2. The addition of oxidants to the UV/TiO2 system showed an increase in degradation efficiency for the treatment of humic acid and hazardous heavy metals. The optimal concentration of oxidants was: H2O2 50 mg l-1, O3 20 g m-3 and K2S2O8 50 mg l-1, respectively. The degradation efficiency of UV/TiO2/oxidant systems for the removal of humic acid and hazardous heavy metals was much greater when H2O2 was used as the oxidant.</P>

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>

고무 및 화학제품제조업 산업장의 작업환경 실태에 관한 조사연구

전종휘,김용완,배기택,김준연,김진옥,김준효 인제대학교 1980 仁濟醫學 Vol.1 No.2

고무 혹은 화학제품제조업 산업장내 각종 유해작업환경 인자 가운데 특히 톨루엔ㆍ키실렌 등과 같은 유기용제가 산업보건학적 견지에서 보아 중요한 유해인자로 고려되었다. 따라서 고무 혹은 화학제품제조업 산업장과 그 근로자들에 대한 보건관리사업은 유기용제 중독의 예방과 조기치료에 중점을 두어야 할 것으로 생각된다. This study was conducted on some rubber and chemical products manufacturing industries of relatively larger sires and 3,356 workers in Busan area over a period of 4 months from June 1 to ,September 30, 1979. The purpose of the study was in investigating the status of working environment in rubber and chemical products manufacturing industries. The summarized results were as follows: 1.The highest and lowest mean values of harmful environmental elements in workroom of rubber products manufacturing industries were noted in cutting process (93.8 dB) and decorative designing(72.3 dB) in case of noise, vulcanizing (6.92 mg/m3) and rolling (5.55 mg/m3) in class II dust, spreading (883.3 ppm and 803.3 ppm, respectively) and decorative designing (155.0 ppm and 93.3 ppm, respectively) in toluene and xylene, and spreading (87.3 ppm) and assembling (61.0 ppm) ill benzene, respectively. Also in chemical products manufacturing industries, they were noted in culling process (96.2 dB) and inspecting (74.3 dB) in case of noise, cutting (9.07 mg/m3) and grinding (2.30 mg/m3) in class II dust, casting (160.0 ppm) and tube (71.7 ppm) in toluene. printing (133.3 ppm and 43.5 ppm respectively) and tube (66.7 ppm and 11.7 ppm, respectively) in xylene and benzene, respectively. 2.The workers of rubber products manufacturing industries who exposed to working environment above threshold limit value of harmful elements were highly noted in pressing process, cutting and compressing in case of noise, mixing, cutting and vulcanizing in class II dust, decorative designing and spreading in toluene and benzene, and spreading in xylene, respectively. Also in chemical products manufacturing, they were highly noted in cutting process, sheet and grinding in case of noise, mixing and cutting in class II dust, and printing and milling in toluene. xylene and benzene, respectively.

DGPS와 Gyro Compass를 이용한 트랙터의 자세검출

정선옥,박원규,김상철,박우풍,장영창 한국농업기계학회 1998 바이오시스템공학 Vol.23 No.2