CO₂-assisted hydrothermal reactions for ginseng extract

Ryu, Jebin,Yoon, Junho,Ryu, Seungmi,Kang, Seokyung,Kang, Mikyung,Kim, Byung-Soo,Lee, Youn-Woo Elsevier 2018 The Journal of supercritical fluids Vol.135 No.-

<P><B>Abstract</B></P> <P>CO<SUB>2</SUB>-assisted hydrothermal reactions were performed for the conversion of intact ginsenosides to the more bioactive ginsenosides, (S)-Rg3, (R)-Rg3, Rk1, and Rg5. The yields of the transformed ginsenosides and anticancer activities were compared for the three processes: conventional steaming, hydrothermal processing, and CO<SUB>2</SUB>-assisted hydrothermal processing. In the CO<SUB>2</SUB>-assisted hydrothermal process, approximately 2 times higher yields of transformed ginsenosides were obtained within 30 min compared to the steaming process, which requires autoclaving for 3 h, at the same temperature of 120 °C. These improvements were attributed to the homogeneous reaction condition and the <I>in-situ</I> generation of carbonic acid. Moreover, the CO<SUB>2</SUB>-assisted hydrothermally processed ginseng showed the highest antiproliferative effects on HT 1080 and MDA-MB-231 cells by stimulating apoptosis. Due to the higher yields of transformed ginsenosides, similar antiproliferative effects could be obtained using only 10–20% of the amounts used in previous studies.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CO<SUB>2</SUB>-assisted hydrothermal reactions were performed for intact ginsenoside conversion. </LI> <LI> Transformed ginsenoside yields were highly increased within a short time. </LI> <LI> The E<SUB>a</SUB> for the decomposition rate of intact ginsenosides was decreased by 16.7%. </LI> <LI> Apoptosis stimulation elicited anticancer effects on HT 1080 and MDA-MB-231 cells. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Nanothin Coculture Membranes with Tunable Pore Architecture and Thermoresponsive Functionality for Transfer-Printable Stem Cell-Derived Cardiac Sheets

Ryu, Seungmi,Yoo, Jin,Jang, Yeongseon,Han, Jin,Yu, Seung Jung,Park, Jooyeon,Jung, Seon Yeop,Ahn, Kyung Hyun,Im, Sung Gap,Char, Kookheon,Kim, Byung-Soo American Chemical Society 2015 ACS NANO Vol.9 No.10

<P>Coculturing stem cells with the desired cell type is an effective method to promote the differentiation of stem cells. The features of the membrane used for coculturing are crucial to achieving the best outcome. Not only should the membrane act as a physical barrier that prevents the mixing of the cocultured cell populations, but it should also allow effective interactions between the cells. Unfortunately, conventional membranes used for coculture do not sufficiently meet these requirements. In addition, cell harvesting using proteolytic enzymes following coculture impairs cell viability and the extracellular matrix (ECM) produced by the cultured cells. To overcome these limitations, we developed nanothin and highly porous (NTHP) membranes, which are ∼20-fold thinner and ∼25-fold more porous than the conventional coculture membranes. The tunable pore size of NTHP membranes at the nanoscale level was found crucial for the formation of direct gap junctions-mediated contacts between the cocultured cells. Differentiation of the cocultured stem cells was dramatically enhanced with the pore size-customized NTHP membrane system compared to conventional coculture methods. This was likely due to effective physical contacts between the cocultured cells and the fast diffusion of bioactive molecules across the membrane. Also, the thermoresponsive functionality of the NTHP membranes enabled the efficient generation of homogeneous, ECM-preserved, highly viable, and transfer-printable sheets of cardiomyogenically differentiated cells. The coculture platform developed in this study would be effective for producing various types of therapeutic multilayered cell sheets that can be differentiated from stem cells.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2015/ancac3.2015.9.issue-10/acsnano.5b03823/production/images/medium/nn-2015-038237_0012.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nn5b03823'>ACS Electronic Supporting Info</A></P>

Reversible Cell Layering for Heterogeneous Cell Assembly Mediated by Ionic Cross-Linking of Chitosan and a Functionalized Cell Surface Membrane

Ryu, Seungmi,Kim, Hyunbum,Kang, Seokyung,Shin, Kwangsoo,Jung, Seon-Yeop,Heo, Jiwoong,Han, Jin,Yoon, Jeong-Kee,Lee, Ju-Ro,Hong, Jinkee,Ahn, Kyung Hyun,Hyeon, Taeghwan,Hwang, Nathaniel Suk-Yeon,Kim, Byu American Chemical Society 2017 Chemistry of materials Vol.29 No.12

<P>Current heterogeneous cell assembly techniques in coculture systems rely on irreversible cell layering or a cell separation membrane. However, the techniques possess major drawbacks of inefficiency in direct interactions of the assembled cell layers and cell separation following coculture, which hamper characterization and therapeutic applications of the cells following coculture. Here, we develop a reversible cell layering platform for assembly of heterogeneous cells that allows both active direct cell cell interactions and facile cell separation. Anionic maleimide-chondroitin-sulfate is grafted onto the surface membrane of myogenic C2C12 cells and human mesenchymal stem cells (hMSCs) to modify the surface charge of the cells without cytotoxicity. A highly porous chitosan thin film is formed in situ interspacing between the heterogeneous cell layers via ionic cross-linking of cationic chitosan and anionic functionalized cells, forming compactly assembled double-layered cell constructs. The chitosan film enables layering of the cells, which allows active direct interactions between the cell layers, and facile delayering of the cells through simple treatment with mild shear stress. The developed platform promotes the myogenic commitment of hMSCs via direct contact with C2C12 cells, mimicking the interactions that trigger stem cell differentiation in vivo. Delivery of the myogenic committed cells to muscle injured animal models shows evident muscle regeneration.</P>

Cellular Layer-by-Layer Coculture Platform Using Biodegradable, Nanoarchitectured Membranes for Stem Cell Therapy

Ryu, Seungmi,Yoo, Jin,Han, Jin,Kang, Seokyung,Jang, Yeongseon,Han, Ho Jae,Char, Kookheon,Kim, Byung-Soo American Chemical Society 2017 Chemistry of materials Vol.29 No.12

<P>Stem cells are regulated in vivo through interactions with the surrounding microenvironments in a three-dimensional (3D) manner. A coculture of stem cells with desired cell types, which recapitulates the complex in vivo cell cell communications, has been reported as an effective method to direct stem cell differentiation into specific lineage. However, conventional bilayer coculture systems employ membranes of microscale thickness and low porosity, which limit interaction between cocultured cells for efficient stem cell differentiation. Furthermore, conventional coculture systems require cell-impairing enzyme treatment to harvest the cells from the membranes. Here, we developed a cellular layer-by-layer (cLbL) coculture platform using biodegradable, nanothin, highly porous (BNTHP) membranes. Equipped with more porous and thinner membranes, the cLbL coculture platform better mimicked the in vivo 3D microenvironment and promoted cellular cross-talks between cocultured cells which occurred in nanoscale, resulting in more efficient stem cell differentiation compared to the conventional bilayer coculture systems. Furthermore, biodegradibility, biocompatibility, and highly flexibility of BNTHP membranes enabled conversion of the cell-attached membranes into implantable 3D cell constructs, thus avoiding harmful enzymatic harvesting of the cells. The cLbL platform may be an effective method to induce stem cell differentiation and facilitate cell implantation for stem cell therapy.</P>

왜 그들은 ‘술방’을 보는가?: 소셜미디어 음주 일인방송 시청동기와 콘텐츠 태도에 대한 탐색적 연구

강승미(Seungmi Kang),유주연(Joo-Yeon Ryu),유승철(Seung-Chul Yoo) 강원대학교 사회과학연구원 2021 사회과학연구 Vol.60 No.2

본 연구는 이용과 충족 이론을 바탕으로 술방 시청동기에 대한 탐색적 분석과 시청동기가 술방 콘텐츠 태도에 미치는 영향에 대한 효과 분석을 실시했다. 술방 시청동기에 대한 탐색적 분석 결과, 정보탐색, 음주 생동감, 시간때 우기, 사회적 상호작용, 대리만족, 재미의 여섯 가지 술방 시청동기를 도출했다. 또한, 성별 및 세대에 따라 시청동기에 차이가 있는지를 분석한 결과, 성별에 따른 차이는 없었으나 세대에 따른 시청동기의 차이는 유의했다. 정보탐색 시청동기는 30대와 40대와 비해 20대에서 더 높게 나타났으며, 음주 생동감 시청동기도 40대에 비해 20대에서 더 높게 나타났다. 시간때우기 시청동기는 50대에 비해 20대, 30대, 40대에서 더 높게 나타났다. 다음으로, 여섯 가지 술방 시청동기가 술방 콘텐츠 태도에 미치는 영향에 대한 효과를 검증한 결과, 술방 시청동기 6개 요인 중 시간때우기, 대리만족 동기를 제외한 나머지 4개 술방 시청동기(정보탐색, 음주 생동감, 사회적 상호작용, 재미)가 술방 콘텐츠 태도에 정(+)의 영향을 미치는 것으로 나타났다. 본 연구는 술방 시청동기를 처음으로 분석했으며, 술방 시청동기 중 ‘음주 생동감’ 동기는 기존 먹방 연구에서 발견하지 못한 술방만의 차별적 동기임을 밝혀냈다는 점에서 초기 연구로서 학술적 함의가 크다. 또한, 술방 콘텐츠 제작 실무와 식품 소셜 미디어 커뮤니케이션 전략에 함의를 준다는 점에서 실용적 가치가 크다. Based on the theory of Use and Gratification, this study conducted an exploratory factor analysis on Sulbang watching motivation and a research of Sulbang watching effect. Sulbang is defined as a drinking broadcast. The findings identified six factors: information seeking, drinking liveliness, time-passing, social interaction, vicarious satisfaction, and entertainment. Also, there was no significant difference in watching motivation by gender. However, three factors, information seeking, drinking liveliness, and time-passing, had a significant difference in watching motivation by generation. In information-seeking motivation, the mean value of 20s respondents was higher than those of 30s and 40s. In drinking liveliness motivation, the mean value of 20s respondents was higher than those of 40s. The mean value of the 50s was lower than those of 20s, 30s, and 40s in time-passing motivation. Also, this study examined whether there is a difference in content attitude depending on the Sulbang watching motivation. The results showed four Sulbang motivations (information seeking, drinking liveliness, social interaction, and entertainment) had a significantly positive effect on the Sulbang content attitude. Research implications are that it presents the first step toward understanding Sulbang watching motivation in an integrated way. Overall, this paper contributes practitioners to build global strategies of Korean food media and discuss youth protection regulations.

Nanothin and Highly Porous Coculture Membranes for Stem Cell-Derived Cardiac Sheets and Chondrogenic Cells-Laden Complexes

Jin YOO,Seungmi RYU,Jin HAN,Yeongseon JANG,Byung-Soo KIM,Kookheon CHAR 한국고분자학회 2016 한국고분자학회 학술대회 연구논문 초록집 Vol.41 No.2

Validation of the Korean Version of Constitution in Chinese Medicine Questionnaire among University Students

HwaSoo Goong,Seungmi Ryu,Lijuan Xu 한국간호과학회 2015 한국간호과학회 학술대회 Vol.2015 No.10

Gold Nanoparticle/Graphene Oxide Hybrid Sheets Attached on Mesenchymal Stem Cells for Effective Photothermal Cancer Therapy

Kang, Seokyung,Lee, Junghee,Ryu, Seungmi,Kwon, Yeji,Kim, Kyung-Hun,Jeong, Dae Hong,Paik, Seung R.,Kim, Byung-Soo American Chemical Society 2017 Chemistry of materials Vol.29 No.8

<P>Cell-mediated nanoparticle delivery has been proposed for an effective cancer therapy. However, there are limitations in loading nanoparticles within cells as the internalized nanoparticles cause cytotoxicity and leak out of the cells via exocytosis. Here, we introduce hybrid sheets composed of gold nanoparticles (AuNPs) and graphene oxide (GO), which stably adhere to the cell surface and exhibit a remarkable photothermal effect. To form AuNP/GO sheets in which GO is sandwiched between two AuNP monolayers, AuNPs are coated with alpha-synuclein protein and subsequently adsorbed onto GO sheets. Attaching AuNP/GO sheets to the tumor-tropic mesenchymal stem cell (MSC) surface enhances the loading efficiency of AuNPs in MSCs by avoiding the cytotoxicity and exocytosis issues. Furthermore, the tight packing of AuNPs on microscaled GO sheets enhances the photothermal effect via strong plasmon coupling between AuNPs. The injection of AuNP/GO sheet-attached MSCs into tumor-bearing mice significantly improves the photothermal therapeutic efficacy by delivering larger amounts of AuNPs to the tumor and generating higher heat at the tumor region compared to injection of AuNP-internalized MSCs. The system of attaching AuNP/GO hybrid sheets to the tumor-tropic cell surface may be an effective platform for cancer therapy.</P>

성별에 따른 심혈관질환자의 건강행위에 미치는 요인

수리주안(Lijuan Xu),유승미(Seungmi Ryu),궁화수(Hwasoo Goong) 한국콘텐츠학회 2015 한국콘텐츠학회논문지 Vol.15 No.3

본 연구는 심혈관질환자의 건강행위를 개선할 수 있는 프로그램을 개발하기 위하여 성별차이를 중심으로 건강행위에 미치는 요인의 차이를 파악하기 위하여 수행된 연구로, 경기도와 충남 소재 2개 대학병원에 내원한 심혈관질환자 228명(남자 114명, 여자114명)을 대상으로 하였다. 자료수집을 위한 설문조사는 2013년 1월부터 2013년 2월까지 실시하였으며 수집된 자료는 SPSS 20.0으로 분석하였다. 연구결과 심혈관질환자 남성과 여성사이의 건강행위이행의 유의한 차이가 있었다. 여성이 건강행위 중 운동습관, 스트레스관리, 금연행위에서 남성보다 건강행위를 더 잘하는 것으로 나타났다. 남성과 여성사이의 건강행위의 예측인자는 남성은 연령, 자기효능감, 의료인 지지, 지각된 장애성, 지각된 민감성, 자율적 동기로 45 %를 차지하였고 여성은 연령, 자율적 동기, 자기효능감, 의료인지지로 51%를 차지하였다. 특히 가장 설명력이 높은 변수는 남성은 자기효능감, 여성은 자율적 동기이었다. 따라서 남성과 여성사이의 건강행위의 예측인자가 유의하게 차이가 있는 본 연구결과를 반영하여 심혈관질환자의 지속적인 건강행위이행을 위하여 간호중재 시 성별 특성에 따른 차별화된 방안이 고려되어야 될 것이다. Purpose: The purpose of the study was to investigate the difference of health behavior modification between male and female patients with cardiovascular disease; and to compare the predictors of health behavior between the male and female subjects. Methods: A comparative study design was used in the study. A total of 228 patients(male 114, female 114) with cardiovascular disease were recruited from outpatients clinics in 2 university hospitals in Korea. Data were analyzed using t-test, X², ANOVA, ANCOVA, Pearson correlation, and multiple regression with SPSS 20.0. Results: There was significant difference of health behavior between male and female patients with cardiovascular disease (F=9.45, p=0.002). The significant predictors of health behavior among male subjects were self-efficacy, perceived barriers, perceived susceptibility, medical support and autonomous motivation, accounting for 45%; the significant predictors of health behavior among female subjects were self-efficacy, medical support and autonomous motivation, accounting for 51%. Conclusions: It is suggested to take different health promotions strategies to maintain the performance of health behaviors among male and female patients with cardiovascular diseases.

밀키트 선택속성이 소비자 만족, 구매의도 및 추천의도에 미치는 영향 : 20~30대 1인 가구 밀키트 소비자를 중심으로

유주연(Joo-Yeon Ryu),강승미(Seungmi Kang),유승철(Seung-Chul Yoo) 한국광고PR실학회 2021 광고PR실학연구 Vol.14 No.3

20~30대 1인 가구는 ‘혼밥’문화와 더불어 HMR 및 밀키트의 급격한 성장을 주도했다. 특히 최근 코로나19 감염병 사태 이후 20~30대를 중심으로 국내외 밀키트 시장의 수요가 더욱 늘어나는 추세다. 밀키트 시장 규모의 급격한 상승에도 불구하고, 밀키트 관련 선행연구는 밀키트의 상위개념인 HMR 연구에만 집중되어 있다. 이에 따라 본 연구는 밀키트의 주요 소비층이자 트렌드 선도자인 20~30대 1인 가구를 중심으로, 밀키트 선택속성(편리, 가격, 품질, 즐김)이 소비자 만족, 구매의도 및 추천의도에 미치는 영향요인을 통합적으로 파악하고자 했다. 본 연구를 위해 밀키트 제품 구매 및 이용 경험이 있는 20~30대 1인 가구를 대상 온라인 설문조사를 진행했다. 연구결과, 밀키트 선택속성 4가지 중 3가지(편리, 가격, 품질) 속성은 만족에 정(+)적 영향을 미쳤으나, 즐김 속성은 만족에 유의한 영향이 없었다. 만족은 구매의도와 추천의도에 정(+)적인 영향을 미쳤다. 또한, 만족은 밀키트 선택속성과 구매의도의 관계를 매개하는 것으로 나타났다. 본 연구결과는 밀키트 제품 연구자 제조업계 및 광고PR 담당자에게 20~30대 1인 가구 소비자 특성과 연관된 기초자료 및 커뮤니케이션 방향성에 대한 함의를 제공한다는 점에서 의미가 크다. As a new consumer market with an increase of about 2.15 million in 2019, single-person households in their 20’s and 30’s in Korea have led to rapid growth in HMR and Meal-Kits by the emergence of new food-related lifestyle trends such as a solo dining trend called “Hon-bap.” Being accelerated by the recent Covid-19 outbreak, the Korean meal-kits market is expected to grow to around 700 billion won by 2024. However, despite this rapid growth of the meal-kits market, the existing studies on meal-kits mainly focus on HMR with the higher concept of meal-kits. Therefore, this study integrates how meal-kits product selection attributes affect satisfaction, purchase intention, and recommendation intention. The sampling of this study was conducted on single-person households in their 20’s and 30’s with experience in purchasing and using meal-kits products, and 314 questionnaires were collected through online surveys. The data were analyzed with frequency analysis, reliability analysis, confirmatory factor analysis, and PLS analysis using SPSS 20.0. The results are as the following: First, the convenience, price, quality properties among meal-kits product selection attributes had a positive effect on satisfaction. Second, satisfaction had a positive impact on purchase intention and recommendation intention. Third, satisfaction partially mediated the relationship between meal-kits product selection attributes and purchase intention. Fourth, satisfaction partially mediated the relationship between meal-kits product selection attributes and recommendation intention.