A molecular zipping/unzipping nano-vehicles sensitive to tumor extracellular pH

Lee, Jung Ok,Lee, Min Ji,Kim, Dongin,Lee, Eun Seong Technomic Pub. Co 2014 Journal of bioactive and compatible polymers Vol.29 No.4

<P>A new class of pH-<I>responsive multivalent host</I>–guest interactions to manipulate polypeptide-based nano-vehicles was developed. Poly(<SMALL>l</SMALL>-lysine) (poly(Lys)) grafted with β-cyclodextrin and 2,3-dimethylmaleic acid was coupled with oleic acid. This new polymer was utilized to fabricate pH-responsive nano-vehicles for antitumor drug doxorubicin delivery. The host–guest (zipping) interaction between β-cyclodextrin and 2,3-dimethylmaleic acid moieties and the hydrophobic interaction between the oleic acid molecules contributed to form self-assembled nano-vehicles. 2,3-Dimethylmaleic acid moieties were highly degradable at a slightly acidic pH (~pH 6.8). These nano-vehicles increased the release of the encapsulated doxorubicin content (by the unzipping interaction between β-cyclodextrin and degraded 2,3-dimethylmaleic acid moieties) when the pH of the solution decreased to 6.8. This event caused a significant increase in the efficiency of cellular doxorubicin uptake and in vitro tumor inhibition.</P>

[P2-27] The Monitoring of Methylmercury in Abyssal Fish Species by GC-ECD

Seong-Cheol Kim,Sung-Im Im,Kwang-Soo Lee,Hyun-A Kim,Kyung-A An,Jin-Wook Jang,Ryun-Kyung Lee,Mi-Ok Kim,Jeong-Min Kim,Yong-Seok Ko,Dae-Byoung Kim,So-Hee Kim 한국식품영양과학회 2007 한국식품영양과학회 학술대회발표집 Vol.2007 No.10

Linoleic Acid Attenuates the Toxic Dose of Bupivacaine-Mediated Reduction of Vasodilation Evoked by the Activation of Adenosine Triphosphate-Sensitive Potassium Channels

Lee, Soo Hee,Kang, Dawon,Ok, Seong-Ho,Kwon, Seong-Chun,Kim, Hyun-Jin,Kim, Eun-Jin,Hong, Jeong-Min,Kim, Ji-Yoon,Bae, Sung Il,An, Seungmin,Sohn, Ju-Tae MDPI 2018 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.19 No.7

<P>The goal of this study was to investigate the effect of lipid emulsion on a toxic dose of local anesthetic-mediated reduction of vasodilation evoked by the ATP-sensitive potassium (K<SUB>ATP</SUB>) channel agonist levcromakalim. The effect of lipid emulsion (LE) and linoleic acid on the local anesthetic-mediated reduction of vasodilation and membrane hyperpolarization evoked by levcromakalim was assessed in isolated endothelium-denuded vessels (rat aorta and mesenteric artery) and aortic vascular smooth muscle cells. The effect of LE and linoleic acid on K<SUB>ATP</SUB> channel activity in transfected HEK-293 cells was investigated, as was the effect of LE on bupivacaine concentration. The efficacy of LE in attenuating the local anesthetic-mediated reduction of vasodilation evoked by levcromakalim was correlated with the lipid solubility of the local anesthetic. Linoleic acid attenuated the bupivacaine-mediated reduction of vasodilation evoked by levcromakalim. LE decreased the bupivacaine-mediated reduction of membrane hyperpolarization evoked by levcromakalim but did not significantly alter the mepivacaine-mediated reduction. LE and linoleic acid both reversed the bupivacaine-mediated decrease of K<SUB>ATP</SUB> activity and enhanced K<SUB>ATP</SUB> activity. LE decreased the bupivacaine concentration. Linoleic acid may be the major contributor to LE-induced attenuation of bupivacaine-mediated reduction of vasodilation evoked by levcromakalim via the direct activation of K<SUB>ATP</SUB> channels and indirect effects.</P>

Bienzymatic<i>Acetylcholinesterase</i>and<i>Choline Oxidase</i>Immobilized Biosensor Based on a Phenyl Carboxylic Acid-Grafted Multiwalled Carbon Nanotube

Lee, So-Ra,Lee, Hyo-Eun,Kang, Yun Ok,Hwang, Wan-Seok,Choi, Seong-Ho Hindawi Limited 2014 Advances In Materials Science And Engineering Vol.2014 No.-

<P>Bienzymatic<I>acetylcholinesterase</I>(AChE) and<I>choline oxidase</I>(ChOx) immobilized biosensor based on a phenyl carboxylic acid-grafted multiwalled carbon nanotube (MWNT) modified glass carbon electrode (GCE) and carbon-screen printed electrode (SPE) was fabricated for acetylcholine detection in human blood samples. Phenyl carboxylic acid-modified MWNT supports were prepared by electrochemical polymerization of 4-carboxyphenyl diazonium salts, which were synthesized by an amine group and sodium nitrite, on the surface of the MWNT-modified GCE and SPE in 0.1 M PBS. The successful fabrication of the AChE-ChOx-immobilized biosensor was confirmed via scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). The sensing range of the biosensor based on a GCE and SPE was 1.0~10 <I>μ</I>M and 10~100 <I>μ</I>M, respectively. The interfering effect of 0.1 M L-ascorbic acid, 0.1 M L-cysteine, and 0.1 M uric acid to 0.1 M acetylcholine was 3.00%, 9.00%, and 3.00%, respectively. Acetylcholine in a human blood sample was detected by the AChE-ChOx-immobilized biosensor.</P>

ATP Binding Cassette Transporter A1 is Involved in Extracellular Secretion of Acetylated APE1/Ref-1

Lee, Yu Ran,Joo, Hee Kyoung,Lee, Eun Ok,Cho, Hyun Sil,Choi, Sunga,Kim, Cuk-Seong,Jeon, Byeong Hwa MDPI AG 2019 INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES Vol.20 No.13

<P>Acetylation of nuclear apurinic/apyrimidinic endonuclease-1/redox factor-1 (APE1/Ref-1) is associated with its extracellular secretion, despite the lack of an N-terminal protein secretion signal. In this study, we investigated plasma membrane targeting and translocation of APE1/Ref-1 in HEK293T cells with enhanced acetylation. While APE1/Ref-1 targeting was not affected by inhibition of the endoplasmic reticulum/Golgi-dependent secretion, its secretion was reduced by inhibitors of ATP-binding cassette (ABC) transporters, and siRNA-mediated down-regulation of ABC transporter A1. The association between APE1/Ref-1 and ABCA1 transporter was confirmed by proximal ligation assay and immunoprecipitation experiments. An APE1/Ref-1 construct with mutated acetylation sites (K6/K7R) showed reduced co-localization with ABC transporter A1. Exposure of trichostatin A (TSA) induced the acetylation of APE1/Ref-1, which translocated into membrane fraction. Taken together, acetylation of APE1/Ref-1 is considered to be necessary for its extracellular targeting via non-classical secretory pathway using the ABCA1 transporter.</P>

Ruegeria conchae sp. nov., isolated from the ark clam Scapharca broughtonii

Lee, Jina,Whon, Tae Woong,Shin, Na-Ri,Roh, Seong Woon,Kim, Jandi,Park, Seong-Kyu,Kim, Min-Soo,Shin, Kee-Sun,Lee, Jung-Sook,Lee, Keun Chul,Kim, Young-Ok,Bae, Jin-Woo Microbiology Society 2012 International journal of systematic and evolutiona Vol.62 No.12

<P>A slightly halophilic, Gram-negative, strictly aerobic, non-motile rod, designated TW15<SUP>T</SUP>, was isolated from an ark clam in South Korea. Growth occurred at 10-37 °C, with 1-5 % (w/v) NaCl and at pH 7.0-10.0. Optimal growth occurred at 25-30 °C, with 2 % (w/v) NaCl and at pH 8.0. Strain TW15<SUP>T</SUP> exhibited both oxidase and catalase activities. The major fatty acids of strain TW15<SUP>T</SUP> were summed feature 8 (consisting of C18 : 1ω7<I>c</I> and/or C18 : 1ω6<I>c</I>) and 11-methyl C18 : 1ω7<I>c</I>. The predominant isoprenoid quinone was ubiquinone-10 (Q-10). The polar lipids of strain TW15<SUP>T</SUP> comprised phosphatidylcholine, phosphatidylglycerol, diphosphatidylglycerol, an unidentified phospholipid, an unidentified aminolipid and five unidentified lipids. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain TW15<SUP>T</SUP> was most closely related to <I>Ruegeria lacuscaerulensis</I> DSM 11314<SUP>T</SUP> (98.0 % 16S rRNA gene sequence similarity). DNA-DNA relatedness with closely related strains was <52±3 %. The DNA G+C content was 55.7 mol%. On the basis of phenotypic, genotypic and phylogenetic data, strain TW15<SUP>T</SUP> represents a novel species of the genus <I>Ruegeria</I>, for which the name <I>Ruegeria conchae</I> sp. nov. is proposed. The type strain is TW15<SUP>T</SUP> ( = KACC 15115<SUP>T</SUP> = JCM 17315<SUP>T</SUP>).</P>

P-10: Comparative Studies of ZnON and ZnO Thin Film Transistors Fabricated by DC Reactive Sputtering Method

Ok, Kyung-Chul,Jeong, Hyun-Jun,Lee, Hyun-Mo,Kim, Hyun-Suk,Park, Jin-Seong Wiley (John WileySons) 2015 SID International Symposium. Digest of Technical P Vol.46 No.1

Population-Based Newborn Hearing Impairment Screening Test Using GJB2 Mutation Analysis

Lee, Kyung-Ok,Jeong, Su-Jin,Byun, Ji-Young,Kim, Jeong-Sook,Lee, Hye-Jung,Seong, Hye-Soon,Kim, Kyung-Tae Korean Society for Clinical Laboratory Science 2007 대한임상검사과학회지(KJCLS) Vol.39 No.2

선천성난청은 비교적 흔한(1/1,000) 유전성질환으로 여러 유전자와 관련이 있으며, 최근에는 connexin 26 단백질내의 GJB2 유전자 돌연변이와의 관련성이 보고되고 있다. 유전질환을 예측하기 위한 유전자선별검사를 임상에 적용하기 위해서는 각 해당 국가별로 정상인에서 유전자돌연변이의 빈도를 구하고, 환자의 결과를 비교하여 활용성을 검토한 후 사용하여야 한다. 본 연구에서는 청력검사(TEOAE)가 정상인 신생아에서 GJB2 유전자 돌연변이 빈도를 구하여 screening test를 위한 한국인의 database를 수립하고자 하였다. 검체로는 437 명의 건강한 신생아의 발꿈치를 천자하여 얻은 혈액을 이용하였고, DNA는 Intron 사의 킷트를 사용하여 추출하였으며, GJB2 PCR을 실시한 후 증폭산물(783 bps)은 2% agarose gel로 전기영동을 실시하였고, DNA 자동염기서열분석기를 이용하여 분석을 실시하였다. 총 437명의 한국인 신생아에서 GJB2 유전자 중 8곳의 돌연변이(35delG, 167delT, 235delC, V27I, V37I, M34T, E114G, I203T)를 분석하였으며, 이 중 5곳에서 돌연변이가 발견되었다. 총 437명 중 301명(68.9%)에서 GJB2 유전자돌연변이가 발견되었는데, 그 중 154명이 단일돌연변이였다. V27I 변이가 271명으로 가장 많이 발견되었으며, 대부분의 V27I 변이는 E114G 변이와 함께 나타났다. E114G 변이는 총 146명, I203T 변이는 17명, V37I 변이는 14명, 235delC 변이는 1명의 순으로 나타났다. 이중돌연변이의 대부분은 V27I/E114G였으며, V27I/I203T는 3명에서 나타났고, 삼중돌연변이 V27I/E114G/I203T는 1명에서 발견되었다. 본 연구결과, PCR을 이용한 자동염기분석검사는 GJB2 유전자의 돌연변이 검출에 매우 유용하며, 본 결과는 향 후 신생아 난청선별검사를 위한 한국인의 database로 활용될 수 있을 것으로 사료된다. Hearing loss is a common congenital disorder that is frequently associated with mutations in the Cx26 gene (GJB2). Recently, the mutation analysis of GJB2 has been used in a newborn screening test for the detection of hearing impairment. Population-based studies should be performed before the application of genetic testing for the identification of deaf newborns. In this study, 8 positions of GJB2 mutations-including 35delG, 167delT, 235delC, V27I, V37I, M34T, E114G, and I203T-were analyzed using PCR-direct sequencing in a total of 437 healthy Korean neonates. DNAs from dried blood spots were extracted using a commercial DNA extraction kit. The PCR-amplified products (783 bps) of the GJB2 gene were detected using 2% agarose gel electrophoresis and subjected to direct sequencing. The sequences were compared with those in the GenBank database by using the BLAST program. In this study, 5 GJB2 mutations -including V27I (79G>A), V37I (109G>A), E114G (341A>G), I203T (608T>C), and 235delC- were found. Of the 437 neonate samples, 301 subjects showed GJB2 mutations (68.9%, 301/437). The V27I mutation was found in 271 subjects and was the most frequent (62.0%, 271/437). The E114G, I203T and V37I mutations were shown in 146, 17 and 14 subjects, respectively. The 235delC mutation was found in 1 subject. The E114G mutation was frequently accompanied by the V27I mutation. V27I/E114G (97.2%, 143/147) was the most common double mutation and 3 subjects had the double mutation V27I/I203T. A triple mutation, V27I/E114G/I203T, was found in 1 subject. In conclusion, PCR-direct sequencing is a convenient tool for the rapid detection of GJB2 mutations and this data might provide information for the genetic counseling of the GJB2 gene.

Detection of Lamivudine-Resistant Mutations of HBV DNA Polymerase Gene Using PCR-Direct Sequencing

Lee, Kyung-Ok,Lee, Hye-Jung,Byun, Ji-Young,Lee, Sung-Yeun,Kim, Jeong-Sook,Jung, Na-Young,Chung, Soo-Jin,Seong, Hye-Soon,Kim, Kyung-Tae Korean Society for Clinical Laboratory Science 2006 대한임상검사과학회지(KJCLS) Vol.38 No.3

최근 만성 B형간염의 치료에 B형간염 바이러스 복제를 저해하여 감염력을 약화시키는 lamivudine이 많이 사용되고 있다. 그러나 이 약제를 장기간 복용할 경우 B형간염 바이러스 DNA polymerase 유전자의 YMDD motif에 아미노산 치환을 일으켜 lamivudine 저항성 B형간염 바이러스가 나타나는 점이 문제시 되고 있다. 본 연구의 목적은 lamivudine 치료를 받은 만성 B형간염 환자에서 PCR-direct sequencing 법을 이용하여 B형간염 바이러스 DNA 중합효소 유전자의 YMDD motif(codon 552)와 codon 528에서 돌연변이 출현빈도를 구하고, HBeAg과의 관련성을 보고자 하였다. 방법은 만성 B형간염 환자의 혈청에서 DNA를 추출하고 DNA 중합효소 유전자의 codon 552와 528을 포함하는 부위에서 선택한 두 쌍의 primer를 이용하여 nested PCR을 실시하였다. 증폭된 PCR 산물은 2% agarose gel에서 전기영동을 한 후, 자동염기서열분석기를 이용하여 sequencing을 실시하였다. 총 207명 중에서 돌연변이는 124명(60%)에서 발견되었으며, 남, 녀에서 차이는 발견되지 않았고, 돌연변이군에서 비돌연변이군에 비해 평균나이가 약간 높게 나타났으나 유의성은 없었다. Codon 552에서 단일돌연변이로는 M552I(50.8%)가 가장 높게 나타났고, 다음으로 M552V(43.5%), M552I/V(5.7%)의 순서로 나타났다. Codon 528에서는 67.0%의 L528M 돌연변이가 발견되었다. Codon 552와 codon 528에서 동시에 발생한 중복돌연변이로는 M552V/L528M(43.6%)이 가장 높게 나타났고, 다음으로 M552I/L528(33.1%) 그리고 M552I/L528M(17.7%)의 순으로 나타났다. Codon 552에서 serine 돌연변이(M528S)는 발견되지 않았으며, L528M은 M552V 돌연변이와 거의 동시에 검출되었다. 본 연구에서 만성 B형간염환자에서 HBeAg의 유무와 lamivudine 돌연변이율과의 상관성은 발견되지 않았으며, PCR-direct sequencing법은 고가의 자동염기서열분석 장비와 숙련된 기술자가 필요하다는 문제점은 있으나, 검체 수가 많은 큰 임상검사실에서는 활용성이 클 것으로 판단된다. 향 후 lamivudine으로 인한 HBV 돌연변이형과 환자의 임상결과의 관련성에 대한 연구가 추가적으로 실시되면, lamivudine을 복용하는 만성 HBV 환자의 치료와 예후에 유용할 것으로 사료된다. Treatment of hepatitis B virus (HBV) with lamivudine is effective in suppressing virus replication and results in reduced inflammatory activity. However the most troublesome problem of lamivudine treatment is the emergence of lamivudine-resistant strains with amino acid substitution in the YMDD motif of DNA polymerase gene during the treatment. The aim of this study was to determine the mutation of YMDD motif (codon 552) and codon 528 in chronic HBV patients with lamivudine therapy using PCR-direct sequencing and to investigate the relationship between lamivudine mediated HBV mutation and HBeAg. HBV DNA was extracted from serum samples of HBV patients and amplified by nested PCR with two sets of primer pairs selected in HBV DNA polymerase gene. Amplified PCR product was analyzed by 2% agarose gel electrophoresis and direct sequencing. HBV mutation was detected in 124 out of 207 samples (60%). Single mutation was 50.8% for M552I, 43.5% for M552V, 5.7% for M552I/V and the L528M mutation was 67.0%. Double mutation was 43.6% for M552V/L528M, 33.1% for M552I/L528(wild type), 17.7% for M552I/L528M and 5.6% for M552I/V/L528M. Serine mutation at YMDD motif (M552S) was not found and the L528M mutation frequently accompanied M552V type. In this study, the typical difference of frequencies for HBV mutation depending on HBeAg was not found. Moreover, the PCR-direct sequencing method used in this study might be a powerful tool for the mutation study in clinical reference laboratories with high volume.

MPEG Postprocessing Algorithm Using Signal Variable Filter

Seong-Geun Kwon,Suk-Hwan Lee,Eung-Ju Lee,Ki-Ryong Kwon,Soo-Yol Ok,Sung-Ho Bae 대한전자공학회 2007 ITC-CSCC :International Technical Conference on Ci Vol.2007 No.7

This paper presents the algorithm for the quantization noise reduction based on variable filter adaptive to edge signal in MPEG postprocessing system. Experimental results show that the proposed algorithm was superior to the conventional algorithms as regards PSNR, which was improved by 0.04-0.20 ㏈, and the subjective image quality.