Semi-quantitative determination of ion transfers at an interface between water and quaternary ammonium polybromide droplets through stochastic electrochemical analysis

Lee, Semi,Park, Sangeun,Kim, Kyung Mi,Chang, Jinho Elsevier 2018 ELECTROCHIMICA ACTA Vol.271 No.-

<P><B>Abstract</B></P> <P>In this article, we present stochastic electrochemical analyses for the semi-quantitative determination of ion transfers (ITs) at an interface between water and electrochemically generated quaternary ammonium polybromide (QBr<SUB>2n+1</SUB>) droplets (water|QBr<SUB>2n+1</SUB>) in QBr aqueous solutions containing different acids (HAs).</P> <P>The concentration of Br<SUP>−</SUP> in QBr<SUB>2n+1</SUB>, <SUB> C B <SUP> r − </SUP> ( Q B <SUB> r 2 n + 1 </SUB> ) </SUB> is linearly proportional to <SUB> C <SUP> A − </SUP> ( a q ) </SUB> with the proportionality constant, which was estimated from the difference between the two partition coefficients of H<SUP>+</SUP> and A<SUP>−</SUP> from water toward QBr<SUB>2n+1</SUB>, <SUB> K <SUP> H + </SUP> </SUB> − <SUB> K <SUP> A − </SUP> </SUB> , and the ratio of the mean activity coefficient of the aqueous over that of the QBr<SUB>2n+1</SUB> phase, <SUB> γ ± , a q </SUB> / <SUB> γ ± , Q B <SUB> r 2 n + 1 </SUB> </SUB> . <SUB> C B <SUP> r − </SUP> ( Q B <SUB> r 2 n + 1 </SUB> ) </SUB> also shows the linear function of <SUB> C <SUP> Q + </SUP> ( a q ) </SUB> with ( <SUB> γ ± , a q </SUB> / <SUB> γ ± , Q B <SUB> r 2 n + 1 </SUB> </SUB> ) <SUB> K <SUP> Q + </SUP> </SUB> as its proportionality constant.</P> <P>The stochastic chronoamperometric analyses of QBr<SUB>2n+1</SUB> droplets during their particle-impacts on Pt UME in acidic solutions containing either <I>N</I>-methyl-<I>N</I>-ethyl pyrrolidinium bromide (MEPBr) or ethylpyridinium bromide (EPyBr) as model QBrs can provide indirect information about <SUB> C B <SUP> r − </SUP> ( Q B <SUB> r 2 n + 1 </SUB> ) </SUB> , and we estimated the relative order to be <SUB> K <SUP> C + </SUP> ( L <SUP> i + </SUP> o r N <SUP> a + </SUP> ) </SUB> , <SUB> K <SUP> H + </SUP> </SUB> , and <SUB> K <SUP> A − </SUP> </SUB> : <SUB> K <SUP> C + </SUP> ( L <SUP> i + </SUP> o r N <SUP> a + </SUP> ) </SUB> < <SUB> K <SUP> H + </SUP> </SUB> < <SUB> K <SUP> A − </SUP> </SUB> , where <SUB> K H S O 4 − </SUB> < <SUB> K C l O 4 − </SUB> < <SUB> K C <SUP> l − </SUP> </SUB> in <SUB> K <SUP> A − </SUP> </SUB> and <SUB> K N <SUP> a + </SUP> </SUB> < <SUB> K L <SUP> i + </SUP> </SUB> in <SUB> K <SUP> C + </SUP> </SUB> . Also, we found that Br<SUP>−</SUP>-IT at water|QBr<SUB>2n+1</SUB> is effectively limited by A<SUP>−</SUP>-IT in the acidic solutions, and Cl<SUP>−</SUP> is most significantly transferred to QBr<SUB>2n+1</SUB>, leading to the complete inhibition of Br<SUP>−</SUP>-IT into QBr<SUB>2n+1</SUB>.</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

<i>Shigella</i> Outer Membrane Protein PSSP-1 Is Broadly Protective against <i>Shigella</i> Infection

Kim, Jae-Ouk,Rho, Semi,Kim, Su Hee,Kim, Heejoo,Song, Hyo Jin,Kim, Eun Jin,Kim, Ryang Yeo,Kim, Eun Hye,Sinha, Anuradha,Dey, Ayan,Yang, Jae Seung,Song, Man Ki,Nandy, Ranjan Kumar,Czerkinsky, Cecil,Kim, American Society for Microbiology 2015 CLINICAL AND VACCINE IMMUNOLOGY Vol.22 No.4

<P>In developing countries, <I>Shigella</I> is a primary cause of diarrhea in infants and young children. Although antibiotic therapy is an effective treatment for shigellosis, therapeutic options are narrowing due to the emergence of antibiotic resistance. Thus, preventive vaccination could become the most efficacious approach for controlling shigellosis. We have identified several conserved protein antigens that are shared by multiple <I>Shigella</I> serotypes and species. Among these, one antigen induced cross-protection against experimental shigellosis, and we have named it pan-<I>Shigella</I> surface protein 1 (PSSP-1). PSSP-1-induced protection requires a mucosal administration route and coadministration of an adjuvant. When PSSP-1 was administered intranasally, it induced cross-protection against <I>Shigella flexneri</I> serotypes 2a, 5a, and 6, <I>Shigella boydii</I>, <I>Shigella sonnei</I>, and <I>Shigella dysenteriae</I> serotype 1. Intradermally administered PSSP-1 induced strong serum antibody responses but failed to induce protection in the mouse lung pneumonia model. In contrast, intranasal administration elicited efficient local and systemic antibody responses and production of interleukin 17A and gamma interferon. Interestingly, blood samples from patients with recent-onset shigellosis showed variable but significant mucosal antibody responses to other conserved <I>Shigella</I> protein antigens but not to PSSP-1. We suggest that PSSP-1 is a promising antigen for a broadly protective vaccine against <I>Shigella</I>.</P>

Leptomycin B Increases Radiosensitization by Trichostain A in HeLa Cells

In Ah Kim(김인아),Jin Ho Kim(김진호),Jin Hee Shin(신진희),Il Han Kim(김일한),Jae Sung Kim(김재성),Hong Gyun Wu(우홍균),Eui Kyu Chie(지의규),Yong Ho Kim(김용호),Bo Kyung Kim(김보경),Semie Hong(홍세미),Sung Whan Ha(하성환),Chan Il Park 대한방사선종양학회 2005 Radiation Oncology Journal Vol.23 No.2

목 적: 히스톤탈아세틸화효소 억제제는 그 자체의 항암효과뿐만 아니라 방사선 감작제로서의 효과가 점차 분명해져가고 있다. 최근 Class I 특이적인 히스톤탈아세틸화효소 억제제의 개발로 계층 특이적인(class specific) 연구가 가능해짐에 따라, 본 연구에서는 서로 다른 히스톤탈아세틸화효소억제제의 방사선감작효과를 비교함과 동시에 p53 발현도의 차이가 히스톤탈아세틸화효소억제제의 방사선 감수성에 미치는 영향을 알아보고자 하였다. 대상 및 방법: 이를 위해 p53 발현도가 매우 낮은 HeLa 세포에 p53의 핵 외 수송을 억제하여 세포질 내 분해를 차단하는 Leptomycin B를 처리하여 p53의 발현도를 현저하게 높인 후, Trichostatin와 SK7041의 방사선 민감도를 비교 관찰하였다. 결 과: 세포생존곡선, SER 및 SF2를 비교 분석 시, p53의 발현이 높은 Leptomycin B 처리군에서 TrichostatinA가 Class I HDAC만을 억제하는 SK7041에 비해 유의하게 높은 방사선 감작효과를 나타내었다. 이는 p53이 Class I 특이적 억제제인 SK7041과 Class I과 II를 모두 억제하는 TSA의 방사선감작효과에 미치는 영향의 차이에 기전적으로 관여함을 시사한다. 결 론: Leptomycin B에 의해 유도된 p53의 발현증가는 Class I과 Class I과 II를 모두 억제하는 TSA의 방사선 감작효과를 증강시킨다. Purpose: Histone deacetylase inhibitors (HDIs) are emerging as potentially useful components of anticancer therapy and their radiosensitizing effects have become evident. Specific HDIs are now available that preferentially inhibit specific HDAC classes; TSA inhibits Class I and II HDACs, and SK7041 inhibits Class I HDACs. Materials and Methods: We tested the differential radiosensitization induced by two different classes of HDIs in HeLa cells. We next tested the hypothesis that p53 expression in cancer cells may influence the susceptibility to HDIs by using pharmacologic modification of the p53 status under an isogenic background. Results: It is interesting that p53 expression in the HeLa cells clearly increased the degree of radiosensitization by TSA compared to that of the class I specific inhibitor SK7041. This suggests that p53 may, in part, be responsible for the mechanistic role for the greater radiosensitization induced by Class I & II inhibitors compared to that of the class I specific inhibitors. Thus, these studies are useful in distinguishing between events mediated solely by the Class I HDACs versus those events involving the other classes of HDACs as well. Conclusion: The anticancer efficacy of targeting Class I and II HDACs, in conjunction with radiation therapy, may be further enhanced by the restoration of p53 expression.

The potential theragnostic (diagnostic+therapeutic) application of exosomes in diverse biomedical fields

Kim, Yong-Seok,Ahn, Jae-Sung,Kim, Semi,Kim, Hyun-Jin,Kim, Shin-Hee,Kang, Ju-Seop The Korean Society of Pharmacology 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.2

Exosomes are membranous vesicles of 30-150 nm in diameter that are derived from the exocytosis of the intraluminal vesicles of many cell types including immune cells, stem cells, cardiovascular cells and tumor cells. Exosomes participate in intercellular communication by delivering their contents to recipient cells, with or without direct contact between cells, and thereby influence physiological and pathological processes. They are present in various body fluids and contain proteins, nucleic acids, lipids, and microRNAs that can be transported to surrounding cells. Theragnosis is a concept in next-generation medicine that simultaneously combines accurate diagnostics with therapeutic effects. Molecular components in exosomes have been found to be related to certain diseases and treatment responses, indicating that they may have applications in diagnosis via molecular imaging and biomarker detection. In addition, recent studies have reported that exosomes have immunotherapeutic applications or can act as a drug delivery system for targeted therapies with drugs and biomolecules. In this review, we describe the formation, structure, and physiological roles of exosomes. We also discuss their roles in the pathogenesis and progression of diseases including neurodegenerative diseases, cardiovascular diseases, and cancer. The potential applications of exosomes for theragnostic purposes in various diseases are also discussed. This review summarizes the current knowledge about the physiological and pathological roles of exosomes as well as their diagnostic and therapeutic uses, including emerging exosome-based therapies that could not be applied until now.

Comparing Perceptions, Determinants, and Needs of Patients, Family Members, Nurses, and Physicians When Making Life-Sustaining Treatment Decisions for Patients with Hematologic Malignancies

Semi Kim,Eun Hye Ham,Dong Yeon Kim,Seung Nam Jang,Min kyeong Kim,Hyun Ah Choi,Yun A Cho,Seung A Lee,Min Jeong Yun 한국호스피스완화의료학회 2022 한국호스피스.완화의료학회지 Vol.25 No.1

Purpose: This descriptive study compared the perceptions, determinants, and needs of patients, family members, nurses, and physicians regarding life-sustaining treatment decisions for patients with hematologic malignancies in the hematology-oncology department of a tertiary hospital in Seoul, Korea. Methods: In total, 147 subjects were recruited, gave written consent, and provided data by completing a structured questionnaire. Data were analyzed using analysis of variance, the chi-square test, and the Fisher exact test. Results: Nurses (F=3.35) and physicians (F=3.57) showed significantly greater familiarity with the Act on Decisions on Life-Sustaining Treatment than patients (F=2.69) and family members (F=2.59); (F=19.58, P<0.001). Many respondents, including 19 (51.4%) family members, 16 (43.2%) physicians, and 11 (29.7%) nurses, agreed that the patient’s opinion had the greatest effect when making life-sustaining treatment decisions. Twelve (33.3%) patients answered that mental, physical, and financial burdens were the most important factors in life-sustaining treatment decisions, and there was a significant difference among the four groups (P<0.001). Twenty-four patients (66.7%), 27 (73.0%) family members, and 21(56.8%) nurses answered that physicians were the most appropriate people to provide information regarding life-sustaining treatment decisions. Unexpectedly, 19 (51.4%) physicians answered that hospice nurse practitioners were the most appropriate people to talk to about life-sustaining treatment (P<0.001). Conclusion: It is of utmost importance that the patient and physician determine when life-sustaining treatment should be withdrawn, with the patient making the ultimate decision. Doctors and nurses have the responsibility to provide detailed information. The goal of end-of-life planning is to ensure patients’ dignity and respect their values.

집단지성을 활용한 예비교사들의 과학지식형성과정탐색

김세미 ( Semi Kim ),김은진 ( Eunjin Kim ),김성원 ( Sung Won Kim ) 한국과학교육학회 2013 한국과학교육학회지 Vol.33 No.5

The purpose of this study was to investigate the process of constructing pre-service teachers` scientific knowledge information through collective intelligence. We selected the` Appropriate Technology` (A.T.) as the subject for formation of scientific knowledge. Twenty nine pre-service teachers of the course `Scientific Thinking and Writing in Science Education` were allowed to freely post information whenever they wanted. They presented their full opinions, interacted with each other, and assessed the other` information on the website for a month. The way of posting was as follows. After one pre-service teacher had written the information about A.T. on the website, the other assessed the text and added or modified the writing. This process continued. We analyzed every writing they posted and questionnaire which contained the reason why they modified the text. The result was as follows. Pre-service teachers formed collective intelligence through four stages. First, pre-service teachers started to find the information related to the subject and they just added the information behind the other`s writing. In the second stage, information was added, too. But me difference was that the information they selected carried values for having certain views. Third, they organized their writings with logical and critical thinking. Finally, they revised their overall writing. The results showed that students could develop their critical thinking and they could learn the way of communication from the process of collective intelligence. We found the forming process of knowledge by collective intelligence, and explored the various involving patterns and thinking activities in the process. Based on this research, we expect the improvement of students` logical and critical thinking through the various classes using collective intelligence.

Broadly protective Shigella vaccine development

Min Jung Kim,Hee Joo Kim,Semi Rho,Seung Young Lee,Man Ki Song,Cecil Czerkinsky,Dong Wook Kim,Jae-Ouk Kim 한국생물공학회 2015 한국생물공학회 학술대회 Vol.2015 No.10

Initial Experience of High-Volume Plasma Exchange In Patients with Acute Liver Failure

( Ji Eun Kim ),( Sejong Chun ),( Dong Hyun Sinn ),( Nam Joong Kim ),( Semi Kim ),( Wonseok Kang ),( Jong Man Kim ),( Gye-seong Choi ),( Jae-won Joh ),( Duck Cho ) 대한간학회 2020 춘·추계 학술대회 (KASL) Vol.2020 No.1

Aims: High-volume plasma exchange (HVP) defined as exchange of 8-12 or 15% of ideal body weight with fresh frozen plasma has shown promising results in improving survival of patients with acute liver failure (ALF). However, real-life clinical evidences are still limited. The aim of this study was to report our initial experience of using HVP as a bridge treatment in patients with ALF. Methods: We retrospectively reviewed 32 consecutive patients who were enlisted for liver transplantation (LT) due to ALF between 2013 and 2020 at Samsung Medical Center in Korea. HVP was initiated in patients with ALF since May 2016 at our institution. Results: During study period, 16 Patients received HVP. After HVP, coagulopathy (prothrombin time, INR, 4.46 [2.32-6.02] vs. 1.48 [1.33-1.76], P<0.05), total bilirubin (22.6 [9.1-26.4] vs. 8.9 [5.6-11.3], P<0.05), ALT (506 [341-1963] vs. 120 [88- 315], P<0.05), and ammonia level (130.6 [123.7-143.8] vs 98.2 [84.2-116.5], P=0.033) were improved. Improvement in hepatic encephalopathy grade was observed in four patients, including three case of spontaneous recovery. The overall survival was better in patients who received HVP than that in patients who did not receive HVP (survival rate: 93.8% vs. 68.8% at 30 days) without overlap in survival curve between the two groups, although the difference between the two was statistically marginal (P=0.068). Among 18 patients with high SOFA score (≥13), the overall survival was significantly better for those who received HVP than those did not (90.9% vs. 28.6%, P=0.003). Conclusions: Initial clinical experience with HVP suggests that HVP can be a viable option to improve outcome for patients presenting with ALF, especially for those with high SOFA score.

A Histone Deacetylase Inhibitor, Trichostatin A, Enhances adiosensitivity by Abrogating G2/M Arrest in Human Carcinoma Cells

In Ah Kim,김진호,Jin Hee Shin,Il Han Kim,김재성,Hong-Gyun Wu,Eui Kyu Chie,Yong Ho Kim,Bo-Kyung Kim,Semie Hong,Seok Won Park,Sung Whan Ha,Charn Il Park 대한암학회 2005 Cancer Research and Treatment Vol.37 No.2

Purpose: Histone deacetylase inhibitors (HDIs) are emerging as potentially useful components in anticancer therapy. In this study, we tried to confirm the radiosensitizing effect of richostatin A (TSA) on a panel of uman carcinoma cell lines and elucidate its mechanism of interaction.Materials and Methods: A549, HeLa and Caski cells were exposed to TSA for 18 hr prior to irradiation, and the cell survival then measured using a clonogenic assay. Western blot and flow cytometric analyses, for histone acetylation, and cell cycle and apoptosis, respectively,were also performed.Results: TSA increased the acetylation of histone H3. The pretreatment of TSA consistently radiosensitized all three cell lines. The SF2 (surviving fraction at 2 Gy) of TSA-treated cells was significantly lower than that of mock treated cells. The SER (sensitizer enhancement ratio) increased in all 3 cell lines, in concentration dependent manners. The TSA treated cells showed abrogation of radiation-induced G2/M arrest, in a concentration dependent manner.Conclusion: The pretreatment of TSA enhanced the radiosensitivity of a panel of human carcinoma cells, which was attributed, in part, to the abrogation of radiationinduced G2/M arrest.

The potential theragnostic (diagnostic+therapeutic) application of exosomes in diverse biomedical fields

Yong-Seok Kim,Jae-Sung Ahn,Semi Kim,Hyun-Jin Kim,Shin-Hee Kim,Ju-Seop Kang 대한생리학회-대한약리학회 2018 The Korean Journal of Physiology & Pharmacology Vol.22 No.2

Exosomes are membranous vesicles of 30-150 nm in diameter that are derived from the exocytosis of the intraluminal vesicles of many cell types including immune cells, stem cells, cardiovascular cells and tumor cells. Exosomes participate in intercellular communication by delivering their contents to recipient cells, with or without direct contact between cells, and thereby influence physiological and pathological processes. They are present in various body fluids and contain proteins,nucleic acids, lipids, and microRNAs that can be transported to surrounding cells. Theragnosis is a concept in next-generation medicine that simultaneously combines accurate diagnostics with therapeutic effects. Molecular components in exosomes have been found to be related to certain diseases and treatment responses, indicating that they may have applications in diagnosis via molecular imaging and biomarker detection. In addition, recent studies have reported that exosomes have immunotherapeutic applications or can act as a drug delivery system for targeted therapies with drugs and biomolecules. In this review, we describe the formation, structure,and physiological roles of exosomes. We also discuss their roles in the pathogenesis and progression of diseases including neurodegenerative diseases, cardiovascular diseases, and cancer. The potential applications of exosomes for theragnostic purposes in various diseases are also discussed. This review summarizes the current knowledge about the physiological and pathological roles of exosomes as well as their diagnostic and therapeutic uses, including emerging exosome-based therapies that could not be applied until now.