Assessment of radiation exposure from cesium-137 contaminated roads for epidemiological studies in Seoul, Korea

Lee, Yun-Keun,Ju, Young-Su,Lee, Won Jin,Hwang, Seung Sik,Yim, Sang-Hyuk,Yoo, Sang-Chul,Lee, Jieon,Choi, Kyung-Hwa,Burm, Eunae,Ha, Mina The Korean Society of Environmental Toxicology 2015 환경독성보건학회지 Vol.30 No.-

Objectives We aimed to assess the radiation exposure for epidemiologic investigation in residents exposed to radiation from roads that were accidentally found to be contaminated with radioactive cesium-137 ($^{137}Cs$) in Seoul. Methods Using information regarding the frequency and duration of passing via the $^{137}Cs$ contaminated roads or residing/working near the roads from the questionnaires that were obtained from 8875 residents and the measured radiation doses reported by the Nuclear Safety and Security Commission, we calculated the total cumulative dose of radiation exposure for each person. Results Sixty-three percent of the residents who responded to the questionnaire were considered as ever-exposed and 1% of them had a total cumulative dose of more than 10 mSv. The mean (minimum, maximum) duration of radiation exposure was 4.75 years (0.08, 11.98) and the geometric mean (minimum, maximum) of the total cumulative dose was 0.049 mSv (<0.001, 35.35) in the exposed. Conclusions An individual exposure assessment was performed for an epidemiological study to estimate the health risk among residents living in the vicinity of $^{137}Cs$ contaminated roads. The average exposure dose in the exposed people was less than 5% of the current guideline.

Laser Desorption/Ionization Mass Spectrometric Assay for Phospholipase Activity Based on Graphene Oxide/Carbon Nanotube Double-Layer Films

Lee, Jieon,Kim, Young-Kwan,Min, Dal-Hee American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.42

<P>A new method for quantitative phopholipase activity assays using mass spectrometry (MS) and a supported thin film consisting of a graphene oxide (GO)/carbon nanotube (CNT) double layer as a substrate for laser desorption ionization (LDI) has been developed. Phospholipids were very efficiently analyzed by LDI−time-of-flight (TOF) MS on the GO/CNT films, presumably because of the affinity of phospholipids for the GO/CNT surface. Therefore, the rate of lipid hydrolysis was conveniently measured using LDI−TOF mass spectra obtained from a GO/CNT surface on which the phospholipid hydrolysis reaction mixtures had been spotted by comparing the mass-peak intensities of reactants and products. The present platform for phospholipase assays based on MS and GO/CNT double-layer films enables quantitative measurements at low cost, allows assays to be performed in a short time, and is compatible with an array format, unlike conventional assay methods.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-42/ja106276j/production/images/medium/ja-2010-06276j_0008.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja106276j'>ACS Electronic Supporting Info</A></P>

Multi-dimensional histone methylations for coordinated regulation of gene expression under hypoxia

Lee, Seongyeol,Lee, Jieon,Chae, Sehyun,Moon, Yunwon,Lee, Ho-Youl,Park, Bongju,Yang, Eun Gyeong,Hwang, Daehee,Park, Hyunsung Oxford University Press 2017 Nucleic acids research Vol.45 No.20

<P><B>Abstract</B></P><P>Hypoxia increases both active and repressive histone methylation levels via decreased activity of histone demethylases. However, how such increases coordinately regulate induction or repression of hypoxia-responsive genes is largely unknown. Here, we profiled active and repressive histone tri-methylations (H3K4me3, H3K9me3, and H3K27me3) and analyzed gene expression profiles in human adipocyte-derived stem cells under hypoxia. We identified differentially expressed genes (DEGs) and differentially methylated genes (DMGs) by hypoxia and clustered the DEGs and DMGs into four major groups. We found that each group of DEGs was predominantly associated with alterations in only one type among the three histone tri-methylations. Moreover, the four groups of DEGs were associated with different TFs and localization patterns of their predominant types of H3K4me3, H3K9me3 and H3K27me3. Our results suggest that the association of altered gene expression with prominent single-type histone tri-methylations characterized by different localization patterns and with different sets of TFs contributes to regulation of particular sets of genes, which can serve as a model for coordinated epigenetic regulation of gene expression under hypoxia.</P>

A New Assay for Endonuclease/Methyltransferase Activities Based on Graphene Oxide

Lee, Jieon,Kim, Young-Kwan,Min, Dal-Hee American Chemical Society 2011 ANALYTICAL CHEMISTRY - Vol.83 No.23

<P>A new endonuclease/methyltransferase activity assay method based on graphene oxide (GO) is developed. Substrate DNA is designed to possess a double-stranded part to serve as a nuclease substrate and a single-stranded part for anchoring the DNA to the GO surface via strong noncovalent binding. Nuclease-mediated DNA hydrolysis induces the recovery of fluorescence intensity of the dye attached to the end of the double-stranded DNA region. This GO-based method allows real-time measurement and quantitative assay for endonuclease/methyltransferase activities in short time.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancham/2011/ancham.2011.83.issue-23/ac201298r/production/images/medium/ac-2011-01298r_0002.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ac201298r'>ACS Electronic Supporting Info</A></P>

A biosensor for the detection of single base mismatches in microRNA

Lee, Jieon,Park, Ginam,Min, Dal-Hee The Royal Society of Chemistry 2015 Chemical communications Vol.51 No.78

<P>Graphene oxide quenches fluorescence corresponding to only a mismatched target due to selective denaturing of the thermo-unstable duplex composed of probe peptide nucleic acid and single base mismatched target RNA and thus, the fluorescence signal only from perfectly matched target RNA is measured.</P> <P>Graphic Abstract</P><P>Graphene oxide enables highly sequence specific nucleic acid detection by selectively removing the signal from a mismatched target/probe duplex. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c5cc04706d'> </P>

Evaluation of the pharmacokinetic and pharmacodynamic drug interactions between cilnidipine and valsartan, in healthy volunteers

Lee, Jieon,Lee, Howard,Jang, Kyungho,Lim, Kyoung Soo,Shin, Dongseong,Yu, Kyung-Sang Dove Medical Press 2014 Drug design, development and therapy Vol.8 No.-

<P><B>Purpose</B></P><P>Although cilnidipine and valsartan are widely coadministered to patients with hypertension, their drug–drug interaction potential has not been investigated. This study compared the pharmacokinetic (PK), pharmacodynamic (PD), and tolerability profiles of cilnidipine and valsartan, both alone and in combination, in healthy male subjects.</P><P><B>Patients and methods</B></P><P>Fifty-four subjects, enrolled into an open-label, single-dose, three-treatment, three-period crossover study, randomly received cilnidipine (10 mg), valsartan (160 mg), or both according to one of six sequences. Blood samples were collected at baseline and up to 24 hours after drug administration in each period. Plasma concentrations of cilnidipine and valsartan were determined by liquid chromatography with tandem mass spectrometry. Maximum plasma concentration (C<SUB>max</SUB>) and area under the concentration-time curve from 0 to the last measurable time (AUC<SUB>last</SUB>) were estimated using a noncompartmental method. Tolerability was evaluated by assessing adverse events (AEs), vital signs, electrocardiograms, and clinical laboratory tests. Blood pressure was also measured for PD assessment.</P><P><B>Results</B></P><P>A total of 51 subjects completed the study. The PK profile of cilnidipine was not significantly affected by coadministered valsartan; the geometric mean ratio and 90% confidence interval (90% CI) of AUC<SUB>last</SUB> for cilnidipine with and without valsartan was 1.04 (0.98–1.10). Likewise, cilnidipine did not affect the PK of valsartan; the geometric mean ratio (90% CI) of AUC<SUB>last</SUB> for valsartan with and without cilnidipine was 0.94 (0.83–1.07). Coadministration of cilnidipine and valsartan reduced blood pressure in an additive way. No serious AEs were reported, and both cilnidipine and valsartan were well tolerated.</P><P><B>Conclusion</B></P><P>Coadministered cilnidipine and valsartan do not cause a significant PK or PD interaction, and they are well tolerated.</P>

A first-in-human, double-blind, placebo-controlled, randomized, dose escalation study of DWP05195, a novel TRPV1 antagonist, in healthy volunteers

Lee, Jieon,Kim, Bo-Hyung,Yu, Kyung-Sang,Kim, Hee Sun,Kim, Ji Duck,Cho, Joo-Youn,Lee, SeungHwan,Gu, Namyi Dove Medical Press 2017 Drug design, development and therapy Vol.11 No.-

<P><B>Objectives</B></P><P>DWP05195 is a transient receptor potential vanilloid 1 (TRPV1) antagonist developed for managing pain. The purpose of this study was to evaluate the pharmacodynamics pharmacokinetics, safety, and tolerability of DWP05195 in healthy subjects. This was a first-in-human randomized, double-blinded, placebo-controlled, dose escalation study.</P><P><B>Subjects and methods</B></P><P>DWP05195 or placebo was administered as a single dose of 10–600 mg in the single-dose study and as 100–400 mg once daily for 8 days in the multiple-dose studies. Each study group consisted of 10 subjects (study drug-to-placebo ratio was 8:2). For pharmacodynamics assessment, the heat pain threshold (HPtr), heat pain tolerance (HPtol), perfusion intensity, and flare area ratio of cutaneous blood flow were measured. Safety and tolerability were evaluated throughout the study.</P><P><B>Results</B></P><P>The maximum plasma concentrations and area under the plasma concentration–time curve from zero to the last measurable time dose-dependently increased. HPtr and HPtol tended to increase more after DWP05195 administration than after placebo administration. HPtr and HPtol tended to dose-dependently increase after administration of DWP05195. Cutaneous blood flow was reduced as the dose of DWP05195 increased during the multiple-dose study. DWP05195 was well tolerated up to 600 and 400 mg single- and multiple-dose administrations, respectively.</P><P><B>Conclusion</B></P><P>The pharmacological activity of DWP05195, measured using HPtr and HPtol, increased as expected in a dose-dependent manner owing to increased systemic exposure, indicating that DWP05195 can be used as a TRPV1 antagonist for pain management.</P>

Pharmacokinetics and bioequivalence of two different 20 mg olmesartan tablets: A randomized, single-dose, two-period crossover study in healthy Korean male volunteers

Jieon Lee,김언혜,유경상,정재용,임성빈,김보형 대한임상약리학회 2015 Translational and Clinical Pharmacology Vol.23 No.2

Olmesartan is an angiotensin receptor blocker (ARB) and is widely used in clinical practice to treathypertension. To compare the pharmacokinetic (PK) parameters and tolerability of two oral formulationsof olmesartan (test drug: OMETAN® 20 mg tablet, reference drug: OLMETEC® 20 mgtablet) and assess their bioequivalence, a randomized, single dose, two-treatment crossover clinicalstudy was conducted. At each period, 40 subjects received the test drug or the reference drug. Bloodsamples were collected at pre-dose and up to 48 h after study drug administration of each period. Plasma concentrations of olmesartan were measured using liquid chromatography-tandem massspectrometry. To evaluate PK profiles, maximum plasma concentration (Cmax) and area under theconcentration-time curve from zero to last measurable time (AUClast) were estimated using a noncompartmentalmethod. Tolerability was evaluated based on the incidence of adverse events, vitalsigns, electrocardiograms, and laboratory tests. A total of 39 subjects completed the study. Thegeometric mean ratio and 90% confidence intervals (CI) of test drug to reference drug were 1.027(0.969–1.088) for Cmax and 1.014 (0.957–1.074) for AUClast, respectively. There were no serious adverseevents and both formulations of olmesartan were well tolerated. The OMETAN 20 mg tabletwas judged to be bioequivalent to the OLMETEC 20 mg tablet

A simple colorimetric paper sensor for sensitive sensing of miRNA

Jieon Lee,Seungmin Park 한국진공학회 2021 한국진공학회 학술발표회초록집 Vol.2021 No.2

MicroRNAs (miRNAs) are short single stranded non-coding RNAs, which have emerged as promising next-generation biomarkers of diverse diseases. In this study, we established a facile paper sensor using graphene oxide (GO) for highly sensitive colorimetric miRNA detection. The proposed strategy is fundamentally based on two principles: 1) peroxidase-mimicking DNAzyme (Dz) mediated double-amplified colorimetric assay in response to target miRNA and 2) GO mediated simple blotting method. This sensor allows clear visualization of the target at sub-nanomolar levels with the naked eye.

YOLOv5 모델 기반 경북대학교 주차공간 탐지 알고리즘

이지언(Jieon Lee),김미주(Meeju Kim),박정민(Jungmin Park),정원준(Wonjun Jung),정찬수(Chansoo Jung),백호기(Hoki Baek) 한국정보기술학회 2023 Proceedings of KIIT Conference Vol.2023 No.6