Induction of oxidative stress by hexavalent chromium in human bronchial epithelial cells

Eun-Jung Park,Misun Kang,Yoojin Jung,Kwangsik Park 환경독성보건학회 2006 한국독성학회 심포지움 및 학술발표회 Vol.- No.-

Temperature-controlled helical inversion of asymmetric triphenylamine-based supramolecular polymers; difference of handedness at the micro- and macroscopic levels

Go, Misun,Choi, Heekyoung,Kim, Ka Young,Moon, Cheol Joo,Choi, Yeonweon,Miyake, Hiroyuki,Lee, Shim Sung,Jung, Sung Ho,Choi, Myong Yong,Jung, Jong Hwa The Royal Society of Chemistry 2019 Organic chemistry frontiers Vol.6 No.8

<P>This study describes the temperature-controlled helicity inversion of supramolecular polymers based on <I>N</I>-triphenylamines (TPAs) bearing different numbers of d-alanine and/or glycine moieties. Despite chiral branching differences, the three investigated TPAs form helical supramolecular polymers <I>via</I> a typical nucleation-elongation model, characteristic of a cooperative assembly. The supramolecular polymer TPA-3, composed of symmetric tri-alanine segments, was more thermodynamically stable compared with TPA-1 and TPA-2, which had one or two alanine segments. More interestingly, at the microscopic level, temperature-dependent circular dichroism (CD) measurements revealed that the left-handed (<I>M</I>-type) helicity of supramolecular polymers TPA-1 and TPA-2 was inverted to the right-handed (<I>P</I>-type) helicity during heating. The (+/−) pattern of the vibrational circular dichroism (VCD) signal in the region of amide groups of self-assembled TPA-1 was also converted to the (−/+) pattern of the VCD signal. This indicates that the conformation of achiral gycine groups with the left-handed orientation was changed to the conformation of the glycine groups with the right-handed orientation. However, at the macroscopic level, the left- and the right-handed helical fibers were observed to coexist in self-assembled TPA-1 and TPA-2 at lower and higher temperatures. In contrast, no helicity conversion with the increase in temperature was observed for self-assembled TPA-3, which exhibited an ambiguous left-handed helical structure with a long helical pitch. Furthermore, the origin of the helical inversion at the microscopic level was supported <I>via</I> computational simulations. The helical inversion was possibly due to a molecular conformational change of flexible glycine moieties during the formation of supramolecular polymers. Based on AFM observations and DFT calculations, we conclude that even though either the positive or the negative signal of supramolecular polymers TPAs was obtained in CD spectra, the right- and the left-handed supramolecular polymer TPAs co-existed at the microscopic and macroscopic levels. Thus, the handedness of supramolecular polymers TPAs was determined by relative distribution of the right- and left-handed helical fibers.</P>

상담 전공 특수대학원생의 상담 누적시간, 수퍼비전 누적시간이 진로걱정에 미치는 영향

정미선(Jung, Misun) 한국웰니스학회 2018 한국웰니스학회지 Vol.13 No.3

본 연구는 상담을 전공으로 하는 특수대학원에 재학 중인 대학원생들을 대상으로 상담 누적시간과 수퍼비전 누적시간 각각이 가지는 진로걱정과의 관계에 있어서 상담자활동 자기효능감이 조절효과를 보이는지를 알아보았다. 이를 위해 상담 전공 특수대학원 재학생 232명을 대상으로 설문조사를 실시하였으며 상관분석과 위계적 회귀분석을 하였다. 그 결과는 다음과 같다. 첫째, 상담 누적시간은 상담자활동 자기효능감과의 상호작용을 통해 진로걱정과의 관계에서 조절효과가 나타났다. 둘째, 수퍼비전 누적시간의 경우에는 상담자활동 자기효능감의 하위요인 중 상담난제 자기효능감과만 상호작용을 통해 진로걱정과의 관계에서 조절효과를 가지는 것으로 나타났다. 이는 상담대학원생들의 진로걱정을 낮추는데 상담자활동 자기효능감이 중요한 변인으로 영향을 미칠 수 있음을 보여주는 결과이다. 마지막으로 이러한 연구 결과를 토대로 시사점과 제한점, 후속연구를 위한 제언을 제시하였다. The purpose of this study was to investigate effects of cumulative counseling hours and cumulative supervision hours on career worries, and identify the role of counselor activity self-efficacy as a moderating variable in the relationship between cumulative counseling hours or cumulative supervision hours and career worries among graduate students with counseling major. A total of 232 counseling graduate students in specialized graduate school of counseling completed the research questionnaire. The results were as follows. First, counselor activity self-efficacy played a moderator in the relationship between the cumulative counseling hours and career worries. Second, the counseling challenges self-efficacy only among counselor activity self-efficacy variables moderated in the relationship between the cumulative supervision hours and career worries. This result indicated that counselor activity self-efficacy could be a preventive factor for career worries. Finally, the limitations and the implications of the study were discussed.

The COVID-19 Pandemic Response System at University Level : The Case of Safe Campus Model at Ewha Womans University

Kyunghee Jung-Choi,Nackmoon Sung,Sun Hwa Lee,Misun Chang,Hee Jung Choi,Chung-Jong Kim,Nam-Kyong Choi,Hanna Kim,Yi-Jun Kim,Whanhee Lee,Hyesook Park,Eunhee Ha Ewha Womans University School of Medicine 2022 EMJ (Ewha medical journal) Vol.45 No.4

In response to the changes in the Coronavirus disease 2019 (COVID-19) epidemic situation, Ewha Womans University established Ewha Safe Campus (ESC), an on-campus infection outbreak management system, to allow students and faculty members to safely resume face-to face classes in 2022. The COVID-19 testing station, Ewha Safe Station, is the core element of ESC. Symptomatic students and faculty members perform a combo swab self-PCR test or receive a nasopharyngeal swab PCR test from experts to prevent the spread of COVID-19 through early detection and management. ESC is significant in that it detects infection risks and proactively implements preemptive measures in a university. The COVID-19 health response system model at the university level was applied for the first time in South Korea, reaching a milestone in the history of university health in South Korea. In particular, it is highly valuable that the test was free of charge, as it enabled all of the examinees to have easy access to the test through joint cooperation with the Seegene Medical Foundation. This is a successful example of cooperation between schools and private institutions for public health improvement. In the future, the direct and indirect effects of the establishment and implementation of ESC need to be evaluated and confirmed, and areas requiring improvements need to be identified in preparation for another infectious disease outbreak in the future.

Survival and Prognosis of Patients with Pilocytic Astrocytoma: A Single-Center Study

( Jae Hui Park ),( Nani Jung ),( Seok Jin Kang ),( Heung Sik Kim ),( El Kim ),( Hee Jung Lee ),( Hye Ra Jung ),( Misun Choe ),( Ye Jee Shim ) 대한뇌종양학회·대한신경종양학회·대한소아뇌종양학회 2019 Brain Tumor Research and Treatment Vol.7 No.2

Background Pilocytic astrocytoma (PA) is a brain tumor that is relatively more common in children and young adults. Methods We retrospectively reviewed the medical records of patients with PA treated at a single center between 1988 and 2018. Results We included 31 subjects with PA. The median age at diagnosis was 13.4 years, and the median follow-up duration was 9.9 years. The total PA group had a 10-year disease-specific survival (DSS) rate of 92.6% [95% confidence interval (CI), 82.6-100] and 10-year progression-free survival (PFS) rate of 52.8% (95% CI, 32.0-73.6). In patients aged <20 years, tumors were more likely to be located in sites in which gross total tumor resection (GTR) was impossible. No statistically significant difference in 10-year DSS was found between the GTR (100%) and non-GTR (89.7%; 95% CI, 76.2-100; p=0.374) groups. However, a statistically significant difference in 10-year PFS was found between the GTR (100%) and non-GTR groups (30.7%; 95% CI, 8.6-52.8; p=0.012). In the non-GTR group, no statistically significant difference in 10-year DSS was found between the patients who received immediate additional chemotherapy and/or radiotherapy (Add-Tx group, 92.9%; 95% CI, 79.4-100) and the non-Add-Tx group (83.3%; 95% CI, 53.5-100; p=0.577). No statistically significant difference in 10- year PFS was found between the Add-Tx group (28.9%; 95% CI, 1.7-56.1) and non-Add-Tx group (33.3%; 95% CI, 0-70.9; p=0.706). Conclusion The PFS of the patients with PA in our study depended only on the degree of surgical excision associated with tumor location. This study is limited by its small number of patients and retrospective nature. A multicenter and prospective study is necessary to confirm these findings.

Enzymatic Prenylation and Oxime Ligation for the Synthesis of Stable and Homogeneous Protein–Drug Conjugates for Targeted Therapy

Lee, Joong‐,jae,Choi, Hyo‐,Jung,Yun, Misun,Kang, YingJin,Jung, Ji‐,Eun,Ryu, Yiseul,Kim, Tae Yoon,Cha, Young‐,je,Cho, Hyun‐,Soo,Min, Jung‐,Joon,Chung, Chul‐,Wo WILEY‐VCH Verlag 2015 Angewandte Chemie Vol.127 No.41

<P><B>Abstract</B></P><P>Targeted therapy based on protein–drug conjugates has attracted significant attention owing to its high efficacy and low side effects. However, efficient and stable drug conjugation to a protein binder remains a challenge. Herein, a chemoenzymatic method to generate highly stable and homogenous drug conjugates with high efficiency is presented. The approach comprises the insertion of the CaaX sequence at the C‐terminal end of the protein binder, prenylation using farnesyltransferase, and drug conjugation through an oxime ligation reaction. MMAF and an EGFR‐specific repebody are used as the antitumor agent and protein binder, respectively. The method enables the precisely controlled synthesis of repebody–drug conjugates with high yield and homogeneity. The utility of this approach is illustrated by the notable stability of the repebody–drug conjugates in human plasma, negligible off‐target effects, and a remarkable antitumor activity in vivo. The present method can be widely used for generating highly homogeneous and stable PDCs for targeted therapy.</P>

Identification of small molecules inducing apoptosis by cell-based assay using fission yeast deletion mutants

Kyung-Sook Chung,Nam-Hui Yim,Seung-Hee Lee,Shin-Jung Choi,Sun-Jung Cho,Yoo-Jin Jung,Jung-Eun Kang,Kwang-Lae Hoe,Dong-Uk Kim,Kyung-Bin Song,Julian Simon,Misun Won 한국생물공학회 2008 한국생물공학회 학술대회 Vol.2008 No.10

Dissociation of Single-Strand DNA: Single-Walled Carbon Nanotube Hybrids by Watson−Crick Base-Pairing

Jung, Seungwon,Cha, Misun,Park, Jiyong,Jeong, Namjo,Kim, Gunn,Park, Changwon,Ihm, Jisoon,Lee, Junghoon American Chemical Society 2010 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.132 No.32

<P>It has been known that single-strand DNA wraps around a single-walled carbon nanotube (SWNT) by π-stacking. In this paper it is demonstrated that such DNA is dissociated from the SWNT by Watson−Crick base-pairing with a complementary sequence. Measurement of field effect transistor characteristics indicates a shift of the electrical properties as a result of this “unwrapping” event. We further confirm the suggested process through Raman spectroscopy and gel electrophoresis. Experimental results are verified in view of atomistic mechanisms with molecular dynamics simulations and binding energy analyses.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/2010/jacsat.2010.132.issue-32/ja102673m/production/images/medium/ja-2010-02673m_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/ja102673m'>ACS Electronic Supporting Info</A></P>

Genetic Variation of the Plastid trnL-trnF Region in Arisaema robustum (Araceae) Using Single Stranded Conformation Polymorphism Analysis

Jung, Yong-Hwan,Kim, Misun,Kang, Sung Ku,An, Hyun Joo,Kim, Seong-Cheol 한국유전학회 2004 Genes & Genomics Vol.26 No.2

The genetic variation among thirty-six accessions of Arisaema robustum distributed on Jeju Island, Korea, was analyzed using single stranded conformation polymorphism (SSCP) analysis. The trnL(UAA)-trnF(GAA) intergenic spacer of the chloroplast DNA (cpDNA) of A. robustum was amplified directly by polymerase chain reaction (PCR) using the universal primers trnLF and trnFR. SSCP analysis of the denatured amplification products was carried out by polyacrylamide (10%) gel electrophoresis followed by ethidium bromide staining. The SSCP analysis identified two different band patterns and comparison of these two nucleotide sequences identified five nucleotide substitutions (transition mutations). We cloned the two SSCP haplotypes in order to sequences the trnL-trnF intergenic spacer. There were 372 base pairs in the trnL-trnF intergenic spacer regions of both types. Different cleavage patterns of four restriction enzymes, DraⅠ, MaeⅢ, PleⅠ, and TfiⅠ, were found. Digestion with DraⅠ and MaeⅢ revealed restriction sites for these enzymes in the wild type, whereas the variant did not contain these restriction sites. The PleⅠ-digested trnL-trnF sequence gave three fragments in the wild type and two fragment in the variant. The SSCP target region, digested with TfiⅠ, produced two fragments in the wild type, and three in the variant. These results show that SSCP analysis of the trnL-trnF intergenic spacer region is a useful approach for inferring genetic variation among members of A. robustum distributed on Jeju Island, Korea.

Promoter methylation of cysteine dioxygenase type 1

Jung-il Choi,Eung-Ho Cho,Sang Bum Kim,Ryounggo Kim,Junhye Kwon,Misun Park,Hye-Jin Shin,Han Suk Ryu,Sun-Hoo Park,Kee-Ho Lee 한국간담췌외과학회 2017 Annals of hepato-biliary-pancreatic surgery Vol.21 No.4

Backgrounds/Aims: Cysteine dioxygenase type 1 (CDO1) acts as a tumor suppressor and is silenced by promoter methylation in various malignancies. The relationship between the CDO1 methylation status and hepatocellular carcinoma (HCC) tumorigenesis was evaluated. Methods: Using a HCC cell line (SNU423), an in vitro demethylation study was performed to confirm whether promoter methylation causes CDO1 down-regulation. The SNU423 cells transfected with the CDO1 cell function was compared to that of naïve cells. An in vivo study using immunohistochemical staining of HCC specimens that were collected from patients who underwent curative liver resection was also performed. Results: CDO1 was activated after demethylation treatment in the HCC specimens. Moreover, tumor cell proliferation, colony-forming, migration, and invasion activities significantly decreased after CDO1 transfection (p<0.05). The percentage of tumors that were larger than 5 cm was higher in patients who had a lower expression of CDO1 (p=0.030). Vascular invasion and histological grade were independent prognostic factors for poor overall and recurrence-free survival. The degree of CDO1 expression was not an independent prognostic factor in this study’s population. Conclusions: These results suggested that methylation down-regulated CDO1 expression in the HCC cells. CDO1 methylation may be a potentially valuable diagnostic biomarker for HCC.