Methionine- R-reductase plays a defensive role against cadmium toxicity in Schizosaccharomyces pombe

Hannah Jo,Kisup Ahn,Chang-Jin Lim 강원대학교 기초과학연구소 2012 기초과학연구 Vol.23 No.-

Methionine sulfoxide reductases (Msrs) are oxidoreductases which catalyze thiol-dependent reduction of free and protein- bound methionine sulfoxides back to corresponding methionine. Methionine-S-sulfoxide (Met-S-SO) and methionine-R-sulfoxide (Met-R-SO) are reduced by methionine-S-sulfoxiede reductase (MsrA) and methionine-R-sulfoxide reductase (MsrB), respectively. In the present study, the cellular functions of MsrB were further characterized using the MsrB-overexpressing recombinant plasmid pFMetSO in the fission yeast. The S. pombe cells harboring pFMetSO exhibited better growth than the vector control cells, when shifted into the fresh medium containing cadmium. In the presence of different levels of cadmium, the S. pombe cells harboring pFMetSO contained diminished NO and reactive oxygen species (RS) levels than the vector control cells. On the contrary, the S. pombe cells harboring pFMetSO contained higher levels of total glutathione (GSH) than the vector control cells under the same treatments. Taken together, the S. pombe MsrB plays a protective role against cadmium toxicity.

Regulatory Dendritic Cells Induced by Mesenchymal Stem Cells Ameliorate Dextran Sodium Sulfate-Induced Chronic Colitis in Mice

( Hannah Jo ),( Young Woo Eom ),( Hyun-soo Kim ),( Hong Jun Park ),( Hee Man Kim ),( Mee-yon Cho ) 대한소화기학회 2018 Gut and Liver Vol.12 No.6

Background/Aims: Regulatory dendritic cells (rDCs), which can be induced by mesenchymal stem cells (MSCs), play an important role in inducing and maintaining homeostasis of regulatory T cells and exhibit anti-inflammatory functions. In this study, we investigated whether MSCs could differentiate DCs into rDCs and compared the therapeutic effects of rDCs and MSCs on dextran sodium sulfate (DSS)-induced chronic colitis mice. Methods: Immature DCs (imDCs) and lipopolysaccharide (LPS)-treated mature DCs (mDCs) were co-cultured with MSCs for 48 hours, and then the profiles of surface markers and cytokines and regulatory roles of these DCs for primary splenocytes were analyzed. In addition, the therapeutic effects of MSCs and DCs co-cultured with MSCs were compared in chronic colitis mice. Results: After co-culture of imDCs (MSC-DCs) or LPS-treated mDCs (LPS+MSCDCs) with MSCs, the expression of CD11c, CD80, CD86, interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ), was decreased, but that of CD11b, IL-10, and transforming growth factor-β (TGF-β) was increased. Furthermore, MSC-DCs and LPS+MSC-DCs induced the expression of CD4, CD25, and Foxp3 in primary splenocytes isolated from mice. In DSS-induced colitis mice, MSCs and MSC-DCs increased colon length, body weight, and survival rate and induced histological improvement. Moreover, in the colon tissues, the expression of IL-6, TNF-α, and IFN-γ decreased, but that of IL-10, TGF-β, and Foxp3 increased in the MSC- and MSC-DC-injected groups. Conclusions: Our data suggest that MSCs differentiate DCs into rDCs, which ameliorate chronic colitis. Thus, rDCs stimulated by MSCs may be therapeutically useful for the treatment of chronic inflammatory diseases. (Gut Liver 2018;12:664-673)

Block‐Copolymer‐Assisted One‐Pot Synthesis of Ordered Mesoporous WO_3−<i>x</i>/Carbon Nanocomposites as High‐Rate‐Performance Electrodes for Pseudocapacitors

Jo, Changshin,Hwang, Jongkook,Song, Hannah,Dao, Anh Ha,Kim, Yong‐,Tae,Lee, Sang Hyup,Hong, Seok Won,Yoon, Songhun,Lee, Jinwoo WILEY‐VCH Verlag 2013 Advanced functional materials Vol.23 No.30

<P><B>Abstract</B></P><P>An ordered mesoporous tungsten‐oxide/carbon (denoted as m‐WO<SUB>3−<I>x</I></SUB>‐C‐s) nanocomposite is synthesized using a simple one‐pot method using polystyrene‐<I>block</I>‐poly(ethylene oxide) (PS‐<I>b</I>‐PEO) as a structure‐directing agent. The hydrophilic PEO block interacts with the carbon and tungsten precursors (resol polymer and WCl<SUB>6</SUB>), and the PS block is converted to pores after heating at 700 °C under a nitrogen flow. The m‐WO<SUB>3−<I>x</I></SUB>‐C‐s nanocomposite has a high Brunauer–Emmett–Teller (BET) surface area and hexagonally ordered pores. Because of its mesoporous structure and high intrinsic density of tungsten oxide, this material exhibits a high average volumetric capacitance and gravimetric capacitance as a pseudocapacitor electrode. In comparison with reduced mesoporous tungsten oxide (denoted as m‐WO<SUB>3−<I>x</I></SUB>‐h), which is synthesized by a tedious hard template approach and further reduction in a H<SUB>2</SUB>/N<SUB>2</SUB> atmosphere, m‐WO<SUB>3−<I>x</I></SUB>‐C‐s shows a high capacitance and enhanced rate performance, as confirmed by cyclic voltammetry, galvanostatic charge/discharge measurements, and electrochemical impedance spectroscopy. The good performance of m‐WO<SUB>3−<I>x</I></SUB>‐C‐s is attributed to the high surface area arising from the mesoporous structure, the large interconnected mesopores, and the low internal resistance from the well‐dispersed reduced tungsten oxide and amorphous carbon composite structure. Here, the amorphous carbon acts as an electrical pathway for effective pseudocapacitor behavior of WO<SUB><I>3‐x</I></SUB>.</P>

Capacitors: Block‐Copolymer‐Assisted One‐Pot Synthesis of Ordered Mesoporous WO_3−<i>x</i>/Carbon Nanocomposites as High‐Rate‐Performance Electrodes for Pseudocapacitors (Adv. Funct. Mater. 30/2013)

Jo, Changshin,Hwang, Jongkook,Song, Hannah,Dao, Anh Ha,Kim, Yong‐,Tae,Lee, Sang Hyup,Hong, Seok Won,Yoon, Songhun,Lee, Jinwoo WILEY‐VCH Verlag 2013 Advanced functional materials Vol.23 No.30

<P>A study by S. Yoon, J. Lee, and co‐workers on the improvement of rate performance highlights an important issue for pseudocapacitor electrode materials. On page 3747, the synthesis of an ordered mesoporous tungsten oxide–carbon nanocomposite is presented via a ‘one‐pot’ soft‐template method. The ordered mesoporous structure, partial reduction of the metal oxide, and the nanosized mixing of the metal oxide/carbon result in both high power and energy density. </P>

Impact of dietary risk factors on cardiometabolic and cancer mortality burden among Korean adults: results from nationally representative repeated cross-sectional surveys 1998–2016

Garam Jo,Hannah Oh,Gitanjali M. Singh,Dahyun Park,Min-Jeong Shin 한국영양학회 2020 Nutrition Research and Practice Vol.14 No.4

BACKGROUND/OBJECTIVES: Dietary factors are important contributors to cardiometabolic and cancer mortality. We examined the secular trends of nine dietary factors (fruits, vegetables, whole grains, nuts and seeds, milk, red meat, processed meat, sugar-sweetened beverages, and calcium) and the associated burdens of cardiometabolic and cancer mortality in Korea using representative cross-sectional survey data from 1998 to 2016. SUBJECTS/METHODS: Using dietary data from Korean adults aged ≥ 25 years in the Korea National Health and Nutrition Examination Survey (KNHANES), we characterized secular trends in intake levels. We performed comparative risk assessment to estimate the population attributable fraction and the number of cardiometabolic and cancer deaths attributable to each dietary factor. RESULTS: A total of 231,148 cardiometabolic and cancer deaths were attributable to nine dietary risk factors in Korea from 1998 to 2016. Suboptimal intakes of fruits and whole grains were the leading contributors. Although the intakes of fruits, vegetables, and whole grains moderately improved over time, the intake levels in 2016 (192.1 g/d, 225.6 g/d, and 10.9 g/d, respectively) remained far below the optimal levels. Deaths attributable to the low intakes of nuts and seeds (4.5 g/d), calcium (440.5 mg/d), and milk (37.1 g/d) and the high intakes of red meat (54.7 g/d), processed meat (4.7 g/d), and sugar-sweetened beverages (33.0 g/d) increased since 1998. Compared with older age groups (≥ 45 years), more unfavorable changes in dietary patterns were observed in the younger population aged 25–44 years, including more sharply increased intakes of processed meat. CONCLUSIONS: We observed improvement in the intakes of fruits, vegetables, and whole grains and unfavorable changes in the intakes of processed meat and sugar-sweetened beverages over the past few decades. Our data suggest that to reduce the chronic disease burden in Korea, more effective nutritional policies and interventions are needed to target these dietary risk factors.

멀티 라이더 퓨전 드라이버의 설계와 구현

백한나(Hannah Baek),조수린(Surin Jo),김강희(Kanghee Kim) 한국정보과학회 2019 한국정보과학회 학술발표논문집 Vol.2019 No.6

Deubiquitinating activity of Sdu1, a putative member of the PPPDE peptidase family, in <i>Schizosaccharomyces pombe</i>

Kim, Yunsik,Jo, Hannah,Lim, Chang-Jin Canadian Science Publishing 2013 Canadian journal of microbiology Vol.59 No.12

<P> The Schizosaccharomyces pombe sdu<SUP>+</SUP> gene encoding a putative member of the PPPDE (Permuted Papain fold Peptidases of DsRNA viruses and Eukaryotes) superfamily was cloned into an Escherichia coli - yeast shuttle vector pRS316, resulting in the recombinant plasmid pYSTP. The determined nucleotide sequence carries 1207 bp, which would encode a protein of 201 amino acid residues. The S. pombe cells harboring pYSTP contained higher sdu1<SUP>+</SUP> mRNA and deubiquitinating activity levels than the vector control cells, indicating that the sdu1<SUP>+</SUP> gene is functioning. They exhibited a better growth in normal rich medium than the vector control cells. When shifted into the fresh medium containing hydrogen peroxide, menadione, or sodium nitroprusside, the S. pombe cells harboring pYSTP were able to grow reasonably well, while the growth of the vector control cells was arrested. The reactive oxygen species and total glutathione levels of the S. pombe cells harboring pYSTP were lower and higher than those of the vector control cells under the same stressful conditions, respectively. They exhibited a lower nitric oxide level than the vector control cells when subjected to sodium nitroprusside. Taken together, the sdu1<SUP>+</SUP> gene encodes an actual protein having deubiquitinating activity and is involved in the response against oxidative and nitrosative stresses in S. pombe. </P>

Children’s Auditory Perception and Linguistic Discrimination

Kyung-Whan Cha,Hannah Jo 한국응용언어학회 2012 응용 언어학 Vol.28 No.2

The purpose of this study is to examine a correlation between auditory perception and linguistic discrimination of children and adults. In a recent study, Cha (2011) demonstrated auditory advantages of young learners over adults. This study investigates the link in auditory perception and linguistic discrimination of two groups of Korean students (kindergarten and college). In order to investigate the auditory capacity of children and adults, the present study uses ultrasonic sounds which are commonly used in the medical field. Each group is investigated for its linguistic discrimination with minimal pairs in Chinese. Because both groups of the students have been already exposed to English, these researchers select unknown phonemes in Chinese, which is a neutral language to both of the subject groups. The results show that the auditory capability of kindergarten children is significantly better than that of college students in linguistic discrimination in distinguishing ten minimal pairs in Chinese. At the same time, this study also finds children’s auditory perception is far better than that of adults.

Sensitive Period of Auditory Perception and Linguistic Discrimination

Cha, Kyung-Whan,Jo, Hannah 한국음성학회 2014 말소리와 음성과학 Vol.6 No.1

The purpose of this study is to scientifically examine Kuhl’s (2011), originally Johnson and Newport’s (1989) critical period graph, from a perspective of auditory perception and linguistic discrimination. This study utilizes two types of experiments (auditory perception and linguistic phoneme discrimination) with five different age groups (5 years, 6-8 years, 9-13 years, 15-17 years, and 20-26 years) of Korean English learners. Auditory perception is examined via ultrasonic sounds that are commonly used in the medical field. In addition, each group is measured in terms of their ability to discriminate minimal pairs in Chinese. Since almost all Korean students already have some amount of English exposure, the researchers selected phonemes in Chinese, an unexposed foreign language for all of the subject groups. The results are almost completely in accordance with Kuhl’s critical period graph for auditory perception and linguistic discrimination; a sensitive age is found at 8. The results show that the auditory capability of kindergarten children is significantly better than that of other students, measured by their ability to perceive ultrasonic sounds and to distinguish ten minimal pairs in Chinese. This finding strongly implies that human auditory ability is a key factor for the sensitive period of language acquisition.

Reactive oxygen species-dependent down-regulation of ubiquitin C-terminal hydrolase in Schizosaccharomyces pombe

조한나,임혜원,권희석,임창진,박광학,진창덕,김경훈,Jo, Hannah,Lim, Hye-Won,Kwon, Hee-Souk,Lim, Chang-Jin,Park, Kwang Hark,Jin, Chang Duck,Kim, Kyunghoon The Microbiological Society of Korea 2016 미생물학회지 Vol.52 No.2

탈유비퀴틴 효소 중 PPPDE 상과에 속하는 Schizosaccharomyces pombe의 $sdu1^+$ 유전자가 유비퀴틴 C-말단 가수분해 효소 활성을 갖는 단백질을 인코딩하고, 산화적 및 일산화질소 스트레스 방어에 관여함이 이전에 밝혀진 바 있다. 예비적인 본 연구는 정상적인 및 과잉발현의 조건에서 S. pombe 유비퀴틴 C-말단 가수분해 효소 활성의 활성산소종 의존성 조절에 초점을 맞추었다. 과산화수소, 수퍼옥사이드 라디칼 생성하는 메나디온 및 일산화질소 생성하는 sodium nitroprusside (SNP)에 노출시킨 S. pombe 세포에서 유비퀴틴 C-말단 가수분해 효소 활성이 감소되었다. 환원형 글루타치온과 그 전구체인 N-acetylcysteine은 과산화수소의 존재 유무에 상관없이 유비퀴틴 C-말단 가수분해 효소 활성을 현저하게 증강시켰다. 그러나, 과산화수소의 부재 시 혹은 존재 시 활성산소종에 미치는 글루타치온과 N-acetylcysteine의 영향은 같은 조건 하에서의 유비퀴틴 C-말단 가수분해 효소 활성 패턴과 상반되었다. 과잉발현의 유비퀴틴 C-말단 가수분해 효소 활성을 보이는 재조합 플라즈미드 pYSTP를 보유하는 S. pombe 세포에서 유비퀴틴 C-말단 가수분해 효소 활성도 과산화수소, 메나디온 및 SNP에의 노출되는 조건에서 감소되었지만, 벡터 대조 세포에서 보다는 높게 유지되었다. 요약하면, S. pombe 유비퀴틴 C-말단 가수분해 효소 활성은 활성산소종에 의하여 하향조절 되지만, 그 의의는 현재로썬 알려지고 있지 않은 상태이다. The Schizosaccharomyces pombe $sdu1^+$ gene, belonging to the PPPDE superfamily of deubiquitinating enzyme (DUB) genes, was previously shown to encode a protein with ubiquitin C-terminal hydrolase (UCH) activity and to participate in the response against oxidative and nitrosative stresses. This work focused on the reactive oxygen species (ROS)-dependent regulation of the S. pombe $sdu1^+$ gene. UCH activities, encoded by the $sdu1^+$ gene, were attenuated in the S. pombe cells exposed to $H_2O_2$, superoxide radical-generating menadione (MD), and nitric oxide (NO)-generating sodium nitroprusside (SNP). Reduced glutathione (GSH) and its precursor N-acetylcysteine (NAC) were able to significantly enhance the UCH activities in the absence or presence of $H_2O_2$. However, the influences of both GSH and NAC on the ROS levels in the absence or presence of $H_2O_2$ were opposite to their effects on the UCH activities under the same conditions. The UCH activities in the Sdu1-overexpressing S. pombe cells were also diminished under exposure to $H_2O_2$, MD and SNP, but still remained to be higher than those in the vector control cells. In brief, it is proposed that the S. pombe $sdu1^+$ gene is regulated by ROS in a negative manner, the meaning of which largely remains elusive.