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Lee KD, Ilavenil S, Karnan M, Yang CJ, Kim D, Choi KC. Novel Bacillus ginsengihumi CMRO6 Inhibits Adipogenesis via p38MAPK/Erk44/42 and Stimulates Glucose Uptake in 3T3-L1 Pre-Adipocytes through Akt/AS160 Signaling. Int J Mol Sci 2022; 23:4727. [PMID: 35563118 PMCID: PMC9104516 DOI: 10.3390/ijms23094727] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Revised: 04/20/2022] [Accepted: 04/22/2022] [Indexed: 12/22/2022] Open
Abstract
The health benefits of probiotics have been known for decades, but there has only been limited use of probiotics in the treatment of obesity. In this study, we describe, for the first time, the role of cell-free metabolites (CM) from Bacillus ginsengihumi-RO6 (CMRO6) in adipogenesis and lipogenesis in 3T3-L1 pre-adipocytes. The experimental results show that CMRO6 treatment effectively reduced lipid droplet accumulation and the expression of CCAAT/enhancer-binding protein α and β (C/EBPα and C/EBPβ), peroxisome proliferator-activated receptor γ (PPAR-γ), serum regulatory binding protein 1c (SREBP-1c), fatty acid-binding protein 4 (FABP4), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC), phosphorylated p38MAPK, and Erk44/42. Additionally, CMRO6 treatment significantly increased glucose uptake and phosphorylated Akt (S473), AS160, and TBC1D1 protein expressions. Considering the results of this study, B. ginsengihumi may be a novel probiotic used for the treatment of obesity and its associated metabolic disorders.
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Affiliation(s)
- Kyung Dong Lee
- Department of Companion Animals, Dongsin University, Naju 58245, Korea;
| | - Soundharrajan Ilavenil
- Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan 31000, Korea; (S.I.); (M.K.)
| | - Muthusamy Karnan
- Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan 31000, Korea; (S.I.); (M.K.)
| | - Chul-Ju Yang
- Department of Animal Science and Technology, Sunchon National University, Suncheon 57922, Korea;
| | - Dahye Kim
- Animal Genomics and Bioinformatics Division, National Institute of Animal Science, Wanju 55365, Korea;
| | - Ki Choon Choi
- Grassland and Forages Division, National Institute of Animal Science, Rural Development Administration, Cheonan 31000, Korea; (S.I.); (M.K.)
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Lee KD, Lee SB, Lim JK, Kang YM, Kim IB, Moon HJ, Lee WJ. Providing essential clinical care for non-COVID-19 patients in a Seoul metropolitan acute care hospital amidst ongoing treatment of COVID-19 patients. J Hosp Infect 2020; 106:673-677. [PMID: 33011308 PMCID: PMC7528870 DOI: 10.1016/j.jhin.2020.09.031] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 09/14/2020] [Accepted: 09/26/2020] [Indexed: 12/13/2022]
Abstract
We assessed infection control efforts by comparing data collected over 20 weeks during a pandemic under a dual-track healthcare system. A decline in non-COVID-19 patients visiting the emergency department by 37.6% (P<0.01) was observed since admitting COVID-19 cases. However, patients with acute myocardial infarction (AMI), stroke, severe trauma and acute appendicitis presenting for emergency care did not decrease. Door-to-balloon time (34.3 (± 11.3) min vs 22.7 (± 8.3) min) for AMI improved significantly (P<0.01) while door-to-needle time (55.7 (± 23.9) min vs 54.0 (± 18.0) min) in stroke management remained steady (P=0.80). Simultaneously, time-sensitive care involving other clinical services, including patients requiring chemotherapy, radiation therapy and haemodialysis did not change.
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Affiliation(s)
- K D Lee
- Department of Infectious Diseases, Myongji Hospital, Hanyang University College of Medicine, Goyang, Republic of Korea
| | - S B Lee
- Department of Physical Medicine and Rehabilitation, Myongji Hospital, Hanyang University College of Medicine, Goyang, Republic of Korea
| | - J K Lim
- Department of Laboratory Medicine, Myongji Hospital, Hanyang University College of Medicine, Goyang, Republic of Korea
| | - Y M Kang
- Department of Infectious Diseases, Myongji Hospital, Hanyang University College of Medicine, Goyang, Republic of Korea
| | - I B Kim
- Department of Emergency Medicine, Myongji Hospital, Hanyang University College of Medicine, Goyang, Republic of Korea
| | - H J Moon
- New Horizon Cancer Institute, Myongji Hospital, Goyang, Republic of Korea
| | - W J Lee
- Department of General Surgery, Myongji Hospital, Goyang, Republic of Korea.
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Yang SM, Park JK, Na YS, Wang ZR, Ko WH, In Y, Lee JH, Lee KD, Kim SK. Nonambipolar Transport due to Electrons with 3D Resistive Response in the KSTAR Tokamak. Phys Rev Lett 2019; 123:095001. [PMID: 31524439 DOI: 10.1103/physrevlett.123.095001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 07/19/2019] [Indexed: 06/10/2023]
Abstract
A small nonaxisymmetric (3D) magnetic field can induce nonambipolar transport of the particle species confined in a tokamak and thus a significant change of plasma rotation. This process can be in a favor of instability control in the region where the tokamak plasma is sufficiently collisional and resistive, as observed in the applications of n=1 resonant magnetic perturbations to the KSTAR tokamak. The plasma rotation can be globally accelerated due to radially drifting electrons and constrained to the electron root, if the radial transport is enhanced by an amplified 3D response. This mechanism is verified by a kinetically self-consistent magnetohydrodynamic modeling for both response and transport, which offers the quantitative explanations on the internal n=1 structure detected by electron-cyclotron-emission imaging and the cocurrent plasma spinning observed in the experiments.
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Affiliation(s)
- S M Yang
- Department of Nuclear Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - J-K Park
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - Yong-Su Na
- Department of Nuclear Engineering, Seoul National University, Seoul 08826, Republic of Korea
| | - Z R Wang
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - W H Ko
- National Fusion Research Institue, Daejeon 305-333, Republic of Korea
| | - Y In
- Ulsan National Institute of Science and Technology, Ulsan 689-798, Republic of Korea
| | - J H Lee
- National Fusion Research Institue, Daejeon 305-333, Republic of Korea
| | - K D Lee
- National Fusion Research Institue, Daejeon 305-333, Republic of Korea
| | - S K Kim
- Department of Nuclear Engineering, Seoul National University, Seoul 08826, Republic of Korea
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Song CE, Kuppusamy P, Jeong YI, Shim HH, Lee KD. Microencapsulation of endophytic LAB (KCC-41) and its probiotic and fermentative potential for cabbage kimchi. Int Microbiol 2019; 22:121-130. [PMID: 30810943 DOI: 10.1007/s10123-018-00034-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 09/13/2018] [Accepted: 10/02/2018] [Indexed: 11/26/2022]
Abstract
The aim of the present study was to isolate novel lactic acid bacteria (LAB) from hairy vetch forage crop and characterize their probiotic and fermentative potential for preparing Korean cabbage kimchi. First, functional characterization of isolated strains such as antagonistic property, auto-aggregation, antibiotic susceptibility, and extracellular enzyme production was performed. The isolated Lactobacillus plantarum KCC-41 strain was able to inhibit pathogenic fungal spore formation. It showed susceptibility to common commercial antibiotics drugs. The selected LAB strain was then subjected to microencapsulation with alginate biopolymer. Its ability to survive in in vitro simulated gastro-intestinal fluid was evaluated. It was also used in the fermentation of cabbage kimchi samples. The encapsulated KCC-41 strain could effectively lead to kimchi fermentation in terms of reducing its pH and dominating bacterial count. It also significantly increased organic acid production than non-encapsulated LAB (KCC-41) for cabbage kimchi samples.
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Affiliation(s)
- Chae Eun Song
- Lifelong Education Center, Chonnam National University, Kwangju, 500-757, Republic of Korea
| | - Palaniselvam Kuppusamy
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan, 330-801, Republic of Korea
| | - Young-Il Jeong
- Biomedical Research Institute, Pusan National University Hospital, Busan, 49241, Republic of Korea
| | - Han Hyo Shim
- Department of Biotechnology, Sunchon National University, Suncheon, Jeonnam, 540-742, Republic of Korea.
- Department of Oriental Medicine Materials, Dongsin University, Naju, 520-714, Republic of Korea.
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongsin University, Naju, 520-714, Republic of Korea.
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Song CE, Shim HH, Kuppusamy P, Jeong YIL, Lee KD. Potential Sustainable Properties of Microencapsulated Endophytic Lactic Acid Bacteria (KCC-42) in In-Vitro Simulated Gastrointestinal Juices and Their Fermentation Quality of Radish Kimchi. Biomed Res Int 2018; 2018:6015243. [PMID: 30255096 PMCID: PMC6140276 DOI: 10.1155/2018/6015243] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Revised: 07/17/2018] [Accepted: 07/29/2018] [Indexed: 11/17/2022]
Abstract
The objective of this study was to investigate alginate microencapsulated lactic acid bacteria (LAB) fermentation quality of radish kimchi sample and its potential survivability in different acidic and alkaline environments. Initially, we isolated 45 LAB strains. One of them showed fast growth pattern with potential probiotic and antifungal activities against Aspergillus flavus with a zone of inhibition calculated with 10, 8, 4mm for the 4th, 5th, and 6th day, respectively. Therefore, this strain (KCC-42) was chosen for microencapsulation with alginate biopolymer. It showed potential survivability in in-vitro simulated gastrointestinal fluid and radish kimchi fermentation medium. The survival rate of this free and encapsulated LAB KCC-42 was 6.85 × 105 and 7.48× 105 CFU/ml, respectively; the viability count was significantly higher than nonencapsulated LAB in simulated gastrointestinal juices (acid, bile, and pancreatin) and under radish kimchi fermentation environment. Kimchi sample added with this encapsulated LAB showed increased production of organic acids compared to nonencapsulated LAB sample. Also, the organic acids such as lactic acid, acetic acid, propionic acid, and succinic acid production in fermented kimchi were measured 59mM, 26mM, 14mM, and 0.6mM of g/DW, respectively. The production of metabolites such as lactic acid, acetic acid, and succinic acid and the bacteria population was high in microencapsulated LAB samples compared with free bacteria added kimchi sample. Results of this study indicate that microencapsulated LAB KCC-42 might be a useful strategy to develop products for food and healthcare industries.
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Affiliation(s)
- Chae Eun Song
- Lifelong Education Center, Chonnam National University, Kwangju 500-757, Republic of Korea
| | - Han Hyo Shim
- Department of Biotechnology, Sunchon National University, Suncheon, Jeonnam 540-742, Republic of Korea
| | - Palaniselvam Kuppusamy
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan 330-801, Republic of Korea
| | - Young-IL Jeong
- Biomedical Research Institute, Pusan National University Hospital, Busan 49241, Republic of Korea
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongsin University, Naju 520-714, Republic of Korea
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Ilavenil S, Kim DH, Srigopalram S, Kuppusamy P, Valan Arasu M, Lee KD, Lee JC, Song YH, Jeong YI, Choi KC. Ferulic acid in Lolium multiflorum inhibits adipogenesis in 3T3-L1 cells and reduced high-fat-diet-induced obesity in Swiss albino mice via regulating p38MAPK and p44/42 signal pathways. J Funct Foods 2017. [DOI: 10.1016/j.jff.2017.08.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
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Shim SY, Lee KD, Lee M. Vaccinium angustifolium Root Extract Suppresses FcɛRI Expression in Human Basophilic KU812F Cells. Prev Nutr Food Sci 2017; 22:9-15. [PMID: 28401082 PMCID: PMC5383136 DOI: 10.3746/pnf.2017.22.1.9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Accepted: 02/20/2017] [Indexed: 12/25/2022] Open
Abstract
Vaccinium angustifolium, commonly known as the lowbush blueberry, is a rich source of flavonoids, with which various human physiological activities have been associated. The present study focuses on the investigation of the effect of the methanolic extract of V. angustifolium root extract (VAE) on high affinity immunoglobulin E receptor (FcɛRI) α chain antibody (CRA-1)-induced allergic reaction in human basophilic KU812F cells. The total phenolic content of VAE was found to be 170±1.9 mg gallic acid equivalents/g. Flow cytometry analysis revealed that the cell surface expression of FcɛRI was suppressed in a concentration-dependent manner upon culture with VAE. Reverse-transcriptase polymerase chain reaction analysis showed that the mRNA level of the FcɛRI α chain was reduced in a concentration-dependent manner as a result of VAE treatment. Western blot analysis revealed that the protein expression of FcɛRI and the phosphorylation of extracellular signal-regulated kinases (ERK) 1/2 were concentration-dependently inhibited by VAE. We determined that VAE inhibited anti-CRA-1-induced histamine release, in addition to the elevation of intracellular calcium concentration ([Ca2+]i), in a concentration-dependent manner. These results indicate that VAE may exert an anti-allergic effect via the inhibition of calcium influx and histamine release, which occurs as a result of the down-regulation of FcɛRI expression through inhibition of ERK 1/2 activation.
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Affiliation(s)
- Sun Yup Shim
- College of Pharmacy, Sunchon National University, Jeonnam 57922, Korea
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongsin University, Jeonnam 58245, Korea
| | - Mina Lee
- College of Pharmacy, Sunchon National University, Jeonnam 57922, Korea
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Shim SY, Lee M, Lee KD. Achyranthes japonica Nakai Water Extract Suppresses Binding of IgE Antibody to Cell Surface FcɛRI. Prev Nutr Food Sci 2016; 21:323-329. [PMID: 28078254 PMCID: PMC5216883 DOI: 10.3746/pnf.2016.21.4.323] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 09/13/2016] [Indexed: 12/23/2022] Open
Abstract
Achyranthes japonica Nakai (AJN) water extract has a variety of physiological properties, including anti-diabetic, anti-cancer, anti-inflammatory, anti-microbial, and anti-oxidative activities. In the present study, the inhibitory effects of AJN extract were investigated in high affinity immunoglobulin E receptor (FcɛRI)-mediated KU812F cells activation. AJN extract showed suppressive effects on histamine release and intracellular calcium [Ca2+]i elevation from anti-FcɛRI antibody (CRA-1)-stimulated cells in a dose-dependent manner. Flow cytometric analysis showed that AJN extract treatment caused a dose-dependent decrease in the cell surface FcɛRI expression and the binding between the cell surface FcɛRI and the IgE antibody. Moreover, reverse transcription-polymerase chain reaction analysis showed that levels of the mRNA for the FcɛRI α chain was decreased by treatment with AJN extract. These results indicate that AJN extract may exert anti-allergic effects via the inhibition of calcium influx and histamine release, which occurs as a result from the down-regulation of the binding of IgE antibody to cell surface FcɛRI. This mechanism may occur through FcɛRI expression inhibition.
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Affiliation(s)
- Sun Yup Shim
- College of Pharmacy, Sunchon National University, Jeonnam 57922, Korea
| | - Mina Lee
- College of Pharmacy, Sunchon National University, Jeonnam 57922, Korea
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongshin University, Jeonnam 58245, Korea
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Ilavenil S, Kim DH, Srigopalram S, Arasu MV, Lee KD, Lee JC, Lee JS, Renganathan S, Choi KC. Potential Application of p-Coumaric Acid on Differentiation of C2C12 Skeletal Muscle and 3T3-L1 Preadipocytes-An in Vitro and in Silico Approach. Molecules 2016; 21:molecules21080997. [PMID: 27490527 PMCID: PMC6274435 DOI: 10.3390/molecules21080997] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/26/2016] [Accepted: 07/27/2016] [Indexed: 01/10/2023] Open
Abstract
Coumaric acid (CA) is a phenolic acid of the hydroxycinnamic acid family, and it has many biological functions such as anti-oxidant, anti-inflammatory, antidiabetic, anti-ulcer, anti-platelet, anti-cancer activities, etc. In the present study, we planned to analyse the potential molecular function of CA on skeletal muscle and preadipocytes differentiation using PCR and Western blot techniques. First, we analysed the impact of CA on C2C12 skeletal muscle differentiation. It revealed that CA treatment inhibited horse serum-induced skeletal muscle differentiation as evidenced by the decreased expression of early myogenic differentiation markers such as Myogenin and myoD via the AMP activated protein kinase- alpha AMPK-α mediated pathway. Furthermore, the level of lipid accumulation and changes in genes and protein expressions that are associated with lipogenesis and lipolysis were analyzed in 3T3-L1 cells. The Oil Red O staining evidenced that CA treatment inhibited lipid accumulation at the concentration of 0.1 and 0.2 mM. Furthermore, coumaric acid treatment decreased the expression of main transcriptional factors such as CCAAT/enhancer binding protein-alpha (C/EBP-α) and peroxisome proliferator-activated receptor gamma-2 (PPAR-γ2). Subsequently, CA treatment decreased the expression of sterol regulatory element binding protein-1 (SREBP-1), fatty acid synthase (FAS), acetyl CoA carboxylase (ACC) and adiponectin. Finally, we identified conformational changes induced by CA in PPAR-γ2 using computational biology tools. It revealed that CA might downregulate the PPAR-γ2 expression by directly binding with amino acids of PPAR-γ2 by hydrogen at 3.26 distance and hydrophobic interactions at 3.90 contact distances. These data indicated that CA suppressed skeletal muscle and preadipocytes differentiation through downregulation of the main transcriptional factors and their downstream targets.
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Affiliation(s)
- Soundharrajan Ilavenil
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan 330-801, Korea.
| | - Da Hye Kim
- Laboratory of Animal Physiology, Graduate School of Agricultural Science, Tohoku University, Aoba, Sendai 980-8577, Japan.
| | - Srisesharam Srigopalram
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan 330-801, Korea.
| | - Mariadhas Valan Arasu
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongsin University, Naju 520-714, Korea.
| | - Jeong Chae Lee
- Research Center of Bioactive Materials, Institute of Molecular Biology and Genetics, Chonbuk National University, Jeonju 561-756, Korea.
| | - Jong Suk Lee
- Biocenter, Gyeonggi Institute of Science and Technology, Suwon 443-270, Korea.
| | - Senthil Renganathan
- Department of Bioinformatics, Marudupandiyar College, Tamilnadu 613-403, India.
| | - Ki Choon Choi
- Grassland and Forage Division, National Institute of Animal Science, Rural Development Administration, Cheonan 330-801, Korea.
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Vedarethinam V, Dhanaraj K, Ilavenil S, Arasu MV, Choi KC, Al-Dhabi NA, Srisesharam S, Lee KD, Kim DH, Dhanapal T, Sivanesan R, Choi HS, Kim YO. Antitumor Effect of the Mannich Base(1,3-bis-((3-Hydroxynaphthalen-2-yl)phenylmethyl)urea) on Hepatocellular Carcinoma. Molecules 2016; 21:E632. [PMID: 27187346 PMCID: PMC6273734 DOI: 10.3390/molecules21050632] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 05/03/2016] [Accepted: 05/04/2016] [Indexed: 01/26/2023] Open
Abstract
The present study was designed to evaluate the antitumor effects of the synthetic Mannich base 1,3-bis-((3-hydroxynaphthalen-2-yl)phenylmethyl)urea (1,3-BPMU) against HEP-G2 hepatoma cells and diethylnitrosamine (DEN)-induced hepatocarcinoma (HCC) in albino rats. In vitro analysis results revealed that 1,3-BPMU showed significant cytotoxicity and cell growth inhibition in HEP-G2 hepatoma cells in a concentration-dependent manner. Furthermore, flow cytometry results indicated that 1,3-BPMU enhanced early and late apoptosis. The maximum apoptosis was exhibited at a concentration of 100 μg/mL of 1,3-BPMU. In in vivo analysis, DEN treatment increased the content of nucleic acids, LPO and the activities of AST, ALT, ALP, LDH, γGT and 5'NT with decreased antioxidant activity as compared to control rats. However, 1,3-BPMU treatment to DEN-induced rats decreased the content of nucleic acids, LPO and the activities of AST, ALT, ALP, LDH, γGT and 5'NT and increased the activities of SOD, CAT, GPx, GST and GR (p < 0.05). Furthermore, 1,3-BPMU enhanced the apoptosis via upregulation of caspase-3 and caspase-9 and the downregulation of Bcl-2 and Bcl-XL mRNA expression as compared to DEN-induced rats. Histological and ultrastructural investigation showed that 1,3-BPMU treatment renovated the internal architecture of the liver in DEN-induced rats. In this study, the molecular and pre-clinical results obtained by treatment of DEN-induced rats with 1,3-BPMU suggested that 1,3-BPMU might be considered as an antitumor compound in the future.
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Affiliation(s)
| | - Karthik Dhanaraj
- Department of Biotechnology, PRIST University, Thanjavur, Tamilnadu 613-403, India.
| | - Soundharrajan Ilavenil
- Grassland and Forage Division, National Institute of Animal Science, Chungnam 330-808, Korea.
| | - Mariadhas Valan Arasu
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Ki Choon Choi
- Grassland and Forage Division, National Institute of Animal Science, Chungnam 330-808, Korea.
| | - Naif Abdullah Al-Dhabi
- Department of Botany and Microbiology, Addiriyah Chair for Environmental Studies, College of Science, King Saud University, Riyadh 11451, Saudi Arabia.
| | - Srigopalram Srisesharam
- Grassland and Forage Division, National Institute of Animal Science, Chungnam 330-808, Korea.
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongshin University, Naju 520-714, Korea.
| | - Da Hye Kim
- United Graduate School of Agricultural Sciences, Tottori University, Tottori 680-8550, Japan.
| | | | - Ravikumar Sivanesan
- Department of Biotechnology, PRIST University, Thanjavur, Tamilnadu 613-403, India.
| | - Han Sung Choi
- Department of Emergency Medicine, College of Medicine, Kyung Hee University, Seoul 02447, Korea.
| | - Young Ock Kim
- Development of Ginseng and Medical Plants Research Institute, Rural Administration, Eumseong 369-873, Korea.
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Bae S, Kim SM, Lee KD, Kim YD, Park S, Kang Y, Lee HS, Kim D. Effects of Pre-annealing on Firing Stability of Atomic Layer-Deposited Al 2O 3. Isr J Chem 2015. [DOI: 10.1002/ijch.201400192] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Lee MC, Sohn CH, Kim SY, Lee KD, Won CJ, Hur N, Kim JY, Cho DY, Noh TW. Stabilization of ferromagnetic ordering in cobaltite double perovskites of La₂CoIrO₆ and La₂CoPtO₆. J Phys Condens Matter 2015; 27:336002. [PMID: 26235708 DOI: 10.1088/0953-8984/27/33/336002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We investigated the local electronic structure and magnetic properties of the cobaltite double perovskites La2CoIrO6 and La2CoPtO6 using Co L2,3-edge x-ray absorption spectroscopy and x-ray magnetic circular dichroism. Despite similarity in the local electronic structure (Co(2+) high-spin states) as well as in the crystal structure (P2(1)/n), only La2CoIrO6 exhibits substantial orbital and spin magnetic moments of Co(2+), whereas they are much weaker in the case of La2CoPtO6. This composition dependence is consistent with the results of magnetization measurements. The details of the mechanism of ferromagnetic ordering in the Co(2+) sublattice in La2CoIrO6 and the lack thereof in La2CoPtO6 are explained in terms of the orbital hybridization of the Co minority-spin t(2g) state and the Ir/Pt j(eff) = 1/2 state.
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Affiliation(s)
- Min-Cheol Lee
- Center for Correlated Electron Systems, Institute for Basic Science (IBS), Seoul National University, Seoul 151-742, Korea. Department of Physics and Astronomy, Seoul National University (SNU), Seoul 151-742, Korea
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Lee HY, Jeong YI, Kim EJ, Lee KD, Choi SH, Kim YJ, Kim DH, Choi KC. Preparation of Caffeic Acid Phenethyl Ester-Incorporated Nanoparticles and Their Biological Activity. J Pharm Sci 2015; 104:144-54. [DOI: 10.1002/jps.24278] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 07/14/2014] [Accepted: 10/21/2014] [Indexed: 12/13/2022]
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Ko WH, Lee HH, Jeon YM, Ida K, Lee JH, Yoon SW, Lee KD, Bae YS, Oh YK, Kwak JG. Rotation characteristics during the resonant magnetic perturbation induced edge localized mode suppression on the KSTAR. Rev Sci Instrum 2014; 85:11E413. [PMID: 25430320 DOI: 10.1063/1.4890402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Measuring rotation profiles with a reliable spatial resolution is one of the critical diagnostics in understanding the plasma behavior especially for the edge transport. In the KSTAR experiments, it has been consistently observed from the charge exchange spectroscopy measurements that the magnetic perturbations not only suppresses edge localized modes (ELMs) but also reduces toroidal rotations. In this paper, toroidal velocities of the carbon impurity and their profile evolutions during ELMy and ELM-suppressed phases are presented. The rotation profiles are shown to collapse immediately after an ELM burst and continue to build up until the next burst that accompanies another collapse. Toroidal rotations following the resonant magnetic perturbations applications are observed to be reduced along with the ELMs suppressed.
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Affiliation(s)
- Won-Ha Ko
- National Fusion Research Institute, Daejeon, South Korea
| | - H H Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - Y M Jeon
- National Fusion Research Institute, Daejeon, South Korea
| | - K Ida
- National Institute for Fusion Science, Nagoya, Japan
| | - J H Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - S W Yoon
- National Fusion Research Institute, Daejeon, South Korea
| | - K D Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - Y S Bae
- National Fusion Research Institute, Daejeon, South Korea
| | - Y K Oh
- National Fusion Research Institute, Daejeon, South Korea
| | - J G Kwak
- National Fusion Research Institute, Daejeon, South Korea
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15
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Lee JH, Oh S, Lee WR, Ko WH, Kim KP, Lee KD, Jeon YM, Yoon SW, Cho KW, Narihara K, Yamada I, Yasuhara R, Hatae T, Yatsuka E, Ono T, Hong JH. Edge profile measurements using Thomson scattering on the KSTAR tokamak. Rev Sci Instrum 2014; 85:11D407. [PMID: 25430170 DOI: 10.1063/1.4890258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In the KSTAR Tokamak, a "Tangential Thomson Scattering" (TTS) diagnostic system has been designed and installed to measure electron density and temperature profiles. In the edge system, TTS has 12 optical fiber bundles to measure the edge profiles with 10-15 mm spatial resolution. These 12 optical fibers and their spatial resolution are not enough to measure the pedestal width with a high accuracy but allow observations of L-H transition or H-L transitions at the edge. For these measurements, the prototype ITER edge Thomson Nd:YAG laser system manufactured by JAEA in Japan is installed. In this paper, the KSTAR TTS system is briefly described and some TTS edge profiles are presented and compared against the KSTAR Charge Exchange Spectroscopy and other diagnostics. The future upgrade plan of the system is also discussed in this paper.
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Affiliation(s)
- J H Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - S Oh
- National Fusion Research Institute, Daejeon, South Korea
| | - W R Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - W H Ko
- National Fusion Research Institute, Daejeon, South Korea
| | - K P Kim
- National Fusion Research Institute, Daejeon, South Korea
| | - K D Lee
- National Fusion Research Institute, Daejeon, South Korea
| | - Y M Jeon
- National Fusion Research Institute, Daejeon, South Korea
| | - S W Yoon
- National Fusion Research Institute, Daejeon, South Korea
| | - K W Cho
- National Fusion Research Institute, Daejeon, South Korea
| | - K Narihara
- National Institute for Fusion Science, Nagoya, Japan
| | - I Yamada
- National Institute for Fusion Science, Nagoya, Japan
| | - R Yasuhara
- National Institute for Fusion Science, Nagoya, Japan
| | - T Hatae
- Japan Atomic Energy Agency, Naka, Japan
| | - E Yatsuka
- Japan Atomic Energy Agency, Naka, Japan
| | - T Ono
- Japan Atomic Energy Agency, Naka, Japan
| | - J H Hong
- Department of Physics, KAIST, South Korea
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Abstract
A Doppler reflectometer has been designed to measure the poloidal propagation velocity on the Korea Superconducting Tokamak Advanced Research (KSTAR) tokamak. It has the operating frequency range of V-band (50-75 GHz) and the monostatic antenna configuration with extraordinary mode (X-mode). The single sideband modulation with an intermediate frequency of 50 MHz is used for the heterodyne measurement with the 200 MHz in-phase and quadrature (I/Q) phase detector. The corrugated conical horn antenna is used to approximate the Gaussian beam propagation and it is installed together with the oversized rectangular waveguides in the vacuum vessel. The first commissioning test of the Doppler reflectometer system on the KSTAR tokamak is planned in the 2014 KSTAR experimental campaign.
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Affiliation(s)
- K D Lee
- National Fusion Research Institute, Yuseong, Daejeon 305-333, South Korea
| | - Y U Nam
- National Fusion Research Institute, Yuseong, Daejeon 305-333, South Korea
| | - Seong-Heon Seo
- National Fusion Research Institute, Yuseong, Daejeon 305-333, South Korea
| | - Y S Kim
- National Fusion Research Institute, Yuseong, Daejeon 305-333, South Korea
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17
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Kim S, Park S, Kim YD, Bae S, Boo H, Kim H, Lee KD, Tark SJ, Kim D. Ag contact properties according to the front grid width and firing temperature for silicon solar cells. J Nanosci Nanotechnol 2014; 14:7774-7778. [PMID: 25942864 DOI: 10.1166/jnn.2014.9452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The effect of peak firing temperature and grid width on the contact properties between Ag metal and silicon (n+ emitter) was investigated for screen-printed silicon solar cells. We confirmed the factors that control the specific contact resistance as follows: (1) the Ag coverage fraction on the silicon surface, d(2) the thickness of the glass layer and (3) the etching depth on the n+ emitter region. The lowest specific contact resistance (8.27 mΩ x cm2) was obtained at the optimum firing temperature (720 degrees C). We also found that the grid width affected the contact quality of Ag paste because the contact width related to the absorbed heat of samples in RTP system. For this reason, when the grid width was further reduced, meaning more heat absorption, more Ag crystallites grew and the glass layer thickened. Light I-V results of a 6-inch silicon solar cell with minimum busbar width were similar to the PC1D simulation results. The efficiency was improved by 0.2% with the reduction of the busbar width.
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Ilavenil S, Arasu MV, Lee JC, Kim DH, Vijayakumar M, Lee KD, Choi KC. Positive regulations of adipogenesis by Italian ryegrass [Lolium multiflorum] in 3T3-L1 cells. BMC Biotechnol 2014; 14:54. [PMID: 24917384 PMCID: PMC4057822 DOI: 10.1186/1472-6750-14-54] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2013] [Accepted: 05/28/2014] [Indexed: 11/12/2022] Open
Abstract
BACK GROUND Intramuscular fat deposition in the meat animal is relatively new strategy for developing the meat quality. Fat deposition is largely depending on the adipocyte proliferation and differentiation. Therefore, we investigated the effect of chloroform extract of L. multiflorum [CELM] on cell proliferation, lipid accumulation and adipocyte differentiation in 3T3-L1 cells and body weight of mouse. RESULTS We identified 6,9-Octadecatrienoic acid, Hexadecanoic acid, 2-hydroxypropanoic acid, butane-2,3-diol and hexane-1,2,3,4,5,6-hexaol in CELM. L. multiflorum extract increased the cell viability, lipid accumulation, cell cycle progression and key transcriptional and secretory factors like PPRAγ2, C/CEBP-α, adiponectin, aP2, GLUT-4, FAS and SREBP-1 mRNA expression as compared with control cells. For in-vivo, mice administered with CELM significantly increased body weight throughout the experiment periods. Further, the identified fatty acids like 3, 6, 9-Octadecatrienoic acid and Hexadecanoic acid was docked with target protein [PPRAγ2] using HEX 6.12. The least binding energy considered as high affinity with target protein. The maximum affinity with the target protein was observed in the Hexadecanoic acid followed by 3, 6, 9-Octadecatrienoic acid. The binding efficacy of Hexadecanoic acid and 3, 6, 9-Octadecatrienoic acid to the active site of PPAR-γ2 may be enhanced the adipocyte differentiations. CONCLUSION These findings suggest that CELM stimulates adipogenesis via activating the PPARγ-mediated signaling pathway in adipocyte which could be useful for the development of meat quality in animals.
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Affiliation(s)
- Soundarrajan Ilavenil
- Grassland and forage division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330-801, Korea
| | - Mariadhas Valan Arasu
- Grassland and forage division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330-801, Korea
- Department of Botany and microbiology, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Jeong-Chae Lee
- Research Center of Bioactive Materials, Chonbuk National University, Jeonju 561-756, Republic of Korea
| | - Da Hye Kim
- The United Graduate School of Agricultural Sciences, Tottori University, Tottori-Shi 680-8553, Japan
| | - Mayakrishnan Vijayakumar
- Grassland and forage division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330-801, Korea
| | - Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongsin University, Naju 520-714, Korea
| | - Ki Choon Choi
- Grassland and forage division, National Institute of Animal Science, RDA, Seonghwan-Eup, Cheonan-Si, Chungnam 330-801, Korea
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Munshi AM, Dheeraj DL, Fauske VT, Kim DC, Huh J, Reinertsen JF, Ahtapodov L, Lee KD, Heidari B, van Helvoort ATJ, Fimland BO, Weman H. Position-controlled uniform GaAs nanowires on silicon using nanoimprint lithography. Nano Lett 2014; 14:960-6. [PMID: 24467394 DOI: 10.1021/nl404376m] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We report on the epitaxial growth of large-area position-controlled self-catalyzed GaAs nanowires (NWs) directly on Si by molecular beam epitaxy (MBE). Nanohole patterns are defined in a SiO2 mask on 2 in. Si wafers using nanoimprint lithography (NIL) for the growth of positioned GaAs NWs. To optimize the yield of vertical NWs the MBE growth parameter space is tuned, including Ga predeposition time, Ga and As fluxes, growth temperature, and annealing treatment prior to NW growth. In addition, a non-negligible radial growth is observed with increasing growth time and is found to be independent of the As species (i.e., As2 or As4) and the growth temperatures studied. Cross-sectional transmission electron microscopy analysis of the GaAs NW/Si substrate heterointerface reveals an epitaxial growth where NW base fills the oxide hole opening and eventually extends over the oxide mask. These findings have important implications for NW-based device designs with axial and radial p-n junctions. Finally, NIL positioned GaAs/AlGaAs core-shell heterostructured NWs are grown on Si to study the optical properties of the NWs. Room-temperature photoluminescence spectroscopy of ensembles of as-grown core-shell NWs reveals uniform and high optical quality, as required for the subsequent device applications. The combination of NIL and MBE thereby demonstrates the successful heterogeneous integration of highly uniform GaAs NWs on Si, important for fabricating high throughput, large-area position-controlled NW arrays for various optoelectronic device applications.
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Affiliation(s)
- A M Munshi
- Department of Electronics and Telecommunications, Norwegian University of Science and Technology (NTNU) , NO-7491 Trondheim, Norway
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Arasu MV, Kim DH, Kim PI, Jung MW, Ilavenil S, Jane M, Lee KD, Al-Dhabi NA, Choi KC. In vitro antifungal, probiotic and antioxidant properties of novel Lactobacillus plantarum K46 isolated from fermented sesame leaf. ANN MICROBIOL 2013. [DOI: 10.1007/s13213-013-0777-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
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21
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Abstract
Background Although cisplatin is extensively used in the clinical field, its intrinsic toxicity limits its clinical use. We investigated nanoparticle formations of poly(acrylic acid-co-methyl methacrylate) (PAA-MMA) incorporating cisplatin and their antitumor activity in vitro and in vivo. Methods Cisplatin-incorporated nanoparticles were prepared through the ion-complex formation between acrylic acid and cisplatin. The anticancer activity of cisplatin-incorporated nanoparticles was assessed with CT26 colorectal carcinoma cells. Results Cisplatin-incorporated nanoparticles have small particle sizes of less than 200 nm with spherical shapes. Drug content was increased according to the increase of the feeding amount of cisplatin and acrylic acid content in the copolymer. The higher acrylic acid content in the copolymer induced increase of particle size and decrease of zeta potential. Cisplatin-incorporated nanoparticles showed a similar growth-inhibitory effect against CT26 tumor cells in vitro. However, cisplatin-incorporated nanoparticles showed improved antitumor activity against an animal tumor xenograft model. Conclusion We suggest that PAA-MMA nanoparticles incorporating cisplatin are promising carriers for an antitumor drug-delivery system.
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Affiliation(s)
- Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongshin University, Naju, South Korea
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22
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Jung YJ, Lee IH, Nou IS, Lee KD, Rashotte AM, Kang KK. BrRZFP1 a Brassica rapa C3HC4-type RING zinc finger protein involved in cold, salt and dehydration stress. Plant Biol (Stuttg) 2013; 15:274-83. [PMID: 22726580 DOI: 10.1111/j.1438-8677.2012.00631.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
C3HC4-type RING zinc finger proteins are known to be essential in the regulation of plant processes, including responses to abiotic stress. Here, we identify, clone and examine the first C3HC4-type RING zinc finger protein (BrRZFP1) from Brassica rapa under stress conditions. Phylogenetic analysis of BrRZFP1 revealed strong sequence similarity to C3HC4-type zinc finger proteins from Arabidopsis that are induced by abiotic stresses. Diverse environmental stresses, including salt and cold, were found to induce BrRZFP1 transcripts greater than eightfold in B. rapa. Additional strong induction was shown of the stress hormone abscisic acid, together suggesting that BrRZFP1 could play a role as a general stress modulator. Similar profiles of induction for each of these stresses was found in both root and shoot tissues, although at much higher levels in roots. Constitutive expression of BrRZFP1 in Nicotiana tabacum was conducted to further analyse how changes in gene expression levels would affect plant stress responses. BrRZFP1 overexpression conferred increased tolerance to cold, salt and dehydration stresses. This was observed in several assays examining growth status throughout development, including increased germination, fresh weight and length of shoots and roots, as well as enhanced chlorophyll retention. These results suggest that the transcription factor BrRZFP1 is an important determinant of stress response in plants and that changes in its expression level in plants could increase stress tolerance.
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Affiliation(s)
- Y J Jung
- Department of Horticulture, Hankyong National University, Ansung City, Gyeonggi-do, South Korea
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23
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Seol J, Lee SG, Park BH, Lee HH, Terzolo L, Shaing KC, You KI, Yun GS, Kim CC, Lee KD, Ko WH, Kwak JG, Kim WC, Oh YK, Kim JY, Kim SS, Ida K. Effects of electron-cyclotron-resonance-heating-induced internal kink mode on the toroidal rotation in the KSTAR Tokamak. Phys Rev Lett 2012; 109:195003. [PMID: 23215391 DOI: 10.1103/physrevlett.109.195003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Indexed: 06/01/2023]
Abstract
It is observed that the magnitude of the toroidal rotation speed is reduced by the central electron cyclotron resonance heating (ECRH) regardless of the direction of the toroidal rotation. The magnetohydrodynamics activities generally appear with the rotation change due to ECRH. It is shown that the internal kink mode is induced by the central ECRH and breaks the toroidal symmetry. When the magnetohydrodynamics activities are present, the toroidal plasma viscosity is not negligible. The observed effects of ECRH on the toroidal plasma rotation are explained by the neoclassical toroidal viscosity in this Letter. It is found that the neoclassical toroidal viscosity torque caused by the internal kink mode damps the toroidal rotation.
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Affiliation(s)
- J Seol
- National Fusion Research Institute, Gwahangno 113, Yuseong-gu, Daejeon 305-333, Korea
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24
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Yun GS, Park HK, Lee W, Choi MJ, Choe GH, Park S, Bae YS, Lee KD, Yoon SW, Jeon YM, Domier CW, Luhmann NC, Tobias B, Donné AJH. Appearance and dynamics of helical flux tubes under electron cyclotron resonance heating in the core of KSTAR plasmas. Phys Rev Lett 2012; 109:145003. [PMID: 23083252 DOI: 10.1103/physrevlett.109.145003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Indexed: 06/01/2023]
Abstract
Dual (or sometimes multiple) flux tubes (DFTs) have been observed in the core of sawtoothing KSTAR tokamak plasmas with electron cyclotron resonance heating. The time evolution of the flux tubes visualized by a 2D electron cyclotron emission imaging diagnostic typically consists of four distinctive phases: (1) growth of one flux tube out of multiple small flux tubes during the initial buildup period following a sawtooth crash, resulting in a single dominant flux tube along the m/n=1/1 helical magnetic field lines, (2) sudden rapid growth of another flux tube via a fast heat transfer from the first one, resulting in approximately identical DFTs, (3) coalescence of the two flux tubes into a single m/n=1/1 flux tube resembling the internal kink mode in the normal sawteeth, which is explained by a model of two current-carrying wires confined on a flux surface, and (4) fast localized crash of the merged flux tube similar to the standard sawtooth crash. The dynamics of the DFTs implies that the internal kink mode is not a unique prerequisite to the sawtooth crash, providing a new insight on the control of the sawtooth.
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Affiliation(s)
- G S Yun
- POSTECH, Pohang 790-784, Korea.
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Seo SH, Lee KD. Development of frequency modulation reflectometer for KSTAR tokamak: data analysis based on Gaussian derivative wavelet. Rev Sci Instrum 2012; 83:10E342. [PMID: 23126999 DOI: 10.1063/1.4742924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A frequency modulation reflectometer has been developed to measure the density profile of the KSTAR tokamak. It has two channels operating in X-mode in the frequency range of Q band (33-50 GHz) and V band (50-75 GHz). The full band is swept in 20 μs. The mixer output is directly digitized at the sampling rate of 100 MSamples∕s. A new phase detection algorithm is developed to analyze both amplitude and frequency modulated signal. The algorithm is benchmarked for a synthesized amplitude modulation-frequency modulation signal. This new algorithm is applied to the data analysis of KSTAR reflectometer.
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Affiliation(s)
- Seong-Heon Seo
- Diagnostics Research Team, National Fusion Research Institute, Daejeon 305-333, South Korea.
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26
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Jeon YM, Park JK, Yoon SW, Ko WH, Lee SG, Lee KD, Yun GS, Nam YU, Kim WC, Kwak JG, Lee KS, Kim HK, Yang HL. Suppression of edge localized modes in high-confinement KSTAR plasmas by nonaxisymmetric magnetic perturbations. Phys Rev Lett 2012; 109:035004. [PMID: 22861864 DOI: 10.1103/physrevlett.109.035004] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/05/2011] [Indexed: 06/01/2023]
Abstract
Edge localized modes (ELMs) in high-confinement mode plasmas were completely suppressed in KSTAR by applying n=1 nonaxisymmetric magnetic perturbations. Initially, the ELMs were intensified with a reduction of frequency, but completely suppressed later. The electron density had an initial 10% decrease followed by a gradual increase as ELMs were suppressed. Interesting phenomena such as a saturated evolution of edge T(e) and broadband changes of magnetic fluctuations were observed, suggesting the change of edge transport by the applied magnetic perturbations.
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Affiliation(s)
- Y M Jeon
- National Fusion Research Institute, Daejeon, Korea.
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27
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Park SR, Han J, Kim C, Koh YY, Kim C, Lee H, Choi HJ, Han JH, Lee KD, Hur NJ, Arita M, Shimada K, Namatame H, Taniguchi M. Chiral orbital-angular momentum in the surface states of Bi2Se3. Phys Rev Lett 2012; 108:046805. [PMID: 22400876 DOI: 10.1103/physrevlett.108.046805] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2011] [Indexed: 05/31/2023]
Abstract
We performed angle-resolved photoemission (ARPES) experiments with circularly polarized light and first-principles density functional calculation with spin-orbit coupling to study surface states of a topological insulator Bi2Se3. We observed circular dichroism (CD) as large as 30% in the ARPES data with upper and lower Dirac cones showing opposite signs in CD. The observed CD is attributed to the existence of local orbital-angular momentum (OAM). First-principles calculation shows that OAM in the surface states is significant and is locked to the electron momentum in the opposite direction to the spin, forming chiral OAM states. Our finding opens a new possibility for strong light-induced spin-polarized current in surface states. We also provide a proof for local OAM origin of the CD in ARPES.
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Affiliation(s)
- Seung Ryong Park
- Institute of Physics and Applied Physics, Yonsei University, Seoul 120-749, Korea
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28
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Chung J, Lee KD, Seo DC, Nam YU, Choi MC. Characterization of a linear device developed for research on advanced plasma imaging and dynamics. Rev Sci Instrum 2010; 81:10E107. [PMID: 21033972 DOI: 10.1063/1.3478671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10(-8) Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.
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Affiliation(s)
- J Chung
- National Fusion Research Institute, Gwahangno 113, Daejeon 305-333, Korea.
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29
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Kogi Y, Jeong SH, Lee KD, Akaki K, Mase A, Kuwahara D, Yoshinaga T, Nagayama Y, Kwon M, Kawahata K. Calibration of electron cyclotron emission radiometer for KSTAR. Rev Sci Instrum 2010; 81:10D916. [PMID: 21033948 DOI: 10.1063/1.3491304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We developed and installed an electron cyclotron emission radiometer for taking measurements of Korea Superconducting Tokamak Advanced Research (KSTAR) plasma. In order to precisely measure the absolute value of electron temperatures, a calibration measurement of the whole radiometer system was performed, which confirmed that the radiometer has an acceptably linear output signal for changes in input temperature. It was also found that the output power level predicted by a theoretical calculation agrees with that obtained by the calibration measurement. We also showed that the system displays acceptable noise-temperature performance around 0.23 eV.
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Affiliation(s)
- Y Kogi
- Fukuoka Institute of Technology, Fukuoka 811-0295, Japan.
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30
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Jeong SH, Lee KD, Kogi Y, Kawahata K, Nagayama Y, Mase A, Kwon M. Electron cyclotron emission diagnostics on KSTAR tokamak. Rev Sci Instrum 2010; 81:10D922. [PMID: 21033954 DOI: 10.1063/1.3491224] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A new electron cyclotron emission (ECE) diagnostics system was installed for the Second Korea Superconducting Tokamak Advanced Research (KSTAR) campaign. The new ECE system consists of an ECE collecting optics system, an overmode circular corrugated waveguide system, and 48 channel heterodyne radiometer with the frequency range of 110-162 GHz. During the 2 T operation of the KSTAR tokamak, the electron temperatures as well as its radial profiles at the high field side were measured and sawtooth phenomena were also observed. We also discuss the effect of a window on in situ calibration.
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Affiliation(s)
- S H Jeong
- Korea Atomic Energy Research Institute, 1045 Daedeokdaero, Daejeon 305-353, Republic of Korea.
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Lee JH, Na HK, Lee SG, Bak JG, Seo DC, Seo SH, Oh ST, Ko WH, Chung J, Nam YU, Lee KD, Ka EM, Oh YK, Kwon M, Jeong SH. Diagnostics for first plasma and development plan on KSTAR. Rev Sci Instrum 2010; 81:063502. [PMID: 20590236 DOI: 10.1063/1.3429942] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The first plasma with target values of the plasma current and the pulse duration was finally achieved on June 13, 2008 in the Korea Superconducting Tokamak Advanced Research (KSTAR). The diagnostic systems played an important role in achieving successful first plasma operation for the KSTAR tokamak. The employed plasma diagnostic systems for the KSTAR first plasma including the magnetic diagnostics, millimeter-wave interferometer, inspection illuminator, H(alpha), visible spectrometer, filterscope, and electron cyclotron emission (ECE) radiometer have provided the main plasma parameters, which are essential for the plasma generation, control, and physics understanding. Improvements to the first diagnostic systems and additional diagnostics including an x-ray imaging crystal spectrometer, reflectometer, ECE radiometer, resistive bolometer, and soft x-ray array are scheduled to be added for the next KSTAR experimental campaign in 2009.
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Affiliation(s)
- J H Lee
- National Fusion Research Institute, Gwahangno 113, Daejeon 305-333, Republic of Korea.
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Chung J, Lee KD, Seo DC, Nam YU, Ko WH, Lee JH, Choi MC. Descriptions of a linear device developed for research on advanced plasma imaging and dynamics. Rev Sci Instrum 2009; 80:103503. [PMID: 19895060 DOI: 10.1063/1.3239405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The research on advanced plasma imaging and dynamics (RAPID) device is a newly developed linear electron cyclotron resonance (ECR) plasma device. It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. A 6 kW 2.45 GHz magnetron is used to produce steady-state ECR plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). The cylindrical stainless steel vacuum chamber is 300 mm in diameter and 750 mm in length and has eight radial and ten axial ports including 6-in. and 8-in. viewing windows for heating and diagnostics. Experimental observation of ECR plasma heating has been recently carried out during the initial plasma operation. The main diagnostic systems including a 94 GHz heterodyne interferometer, a high-resolution 25 channel one-dimensional array spectrometer, a single channel survey spectrometer, and an electric probe have been also prepared. The RAPID device is a flexible simulator for the understanding of tokamak edge plasma physics and new diagnostic system development. In this work, we describe the RAPID device and initial operation results.
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Affiliation(s)
- J Chung
- National Fusion Research Institute, Gwahangno 113, Daejeon 305-333, Korea.
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Lee KD, Gray EJ, Mabood F, Jung WJ, Charles T, Clark SRD, Ly A, Souleimanov A, Zhou X, Smith DL. The class IId bacteriocin thuricin-17 increases plant growth. Planta 2009; 229:747-55. [PMID: 19083012 DOI: 10.1007/s00425-008-0870-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Accepted: 11/21/2008] [Indexed: 05/24/2023]
Abstract
The mechanisms by which many plant growth promoting rhizobacteria (PGPR) affect plants are unknown. We recently isolated a rhizosphere bacterium (Bacillus thuringiensis NEB17), that promotes soybean growth and screened the liquid growth medium in which it grew for plant growth stimulating materials. We have also shown that it produces a bacteriocin (named by us as thuricin-17 and a member of the recently described class IId bacteriocins). Here we show that application of this bacteriocin to leaves (spray) or roots (drench) directly stimulates the growth of both a C(3) dicot (soybean) and a C(4) monocot (corn). This growth stimulation is similar in nature to that previously seen when plants are treated with Nod factors. Strain NEB17 contains three copies of the gene for thuricin 17 that code for identical amino acid sequences. These two lines of evidence suggest that the dual functions of these proteins may have constrained their evolution. This is the first report of direct plant growth enhancement by a bacteriocin.
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Affiliation(s)
- Kyung Dong Lee
- Department of Oriental Medicine Materials, Dongshin University, 252 Daeho-dong, Naju, Jeonnam, 520-714, South Korea
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Abstract
A 280 GHz single-channel horizontal millimeter-wave interferometer system has been fabricated and installed for plasma electron density measurements on the Korea Superconducting Tokamak Advanced Research (KSTAR). A retractable cassette system has been adopted for deep positioning of the interferometer system on large cryostat. The cassette system contains a pneumatic vacuum window shutter and a beam focusing module. The focusing module consists of antennas and aluminum concave mirrors, where an incident beam is reflected on a specially designed carbon inner-wall tile. The module enhances receiving beam power and reduces phase errors due to unexpected beam reflections on a vacuum vessel. Microwave components such as oscillators and mixers are located 2 m away from cryostat with a shielding box. Intermediate frequency signals generated by mixers are transmitted to a diagnostics room, and the phase difference between these signals is measured using a multifringe counting phase comparator. A beam path analysis has been performed for a triangular beam path geometry. An effective line-integrated density can be deduced from measured line-integrated density with these results. A beam path length error due to plasma refraction effect has been determined with various plasma conditions.
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Affiliation(s)
- Y U Nam
- National Fusion Research Institute, Gwahangno 113, Daejeon 305-333, Republic of Korea.
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Supanjani S, Habib A, Mabood F, Lee KD, Donnelly D, Smith DL. Nod factor enhances calcium uptake by soybean. Plant Physiol Biochem 2006; 44:866-72. [PMID: 17092733 DOI: 10.1016/j.plaphy.2006.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2005] [Accepted: 10/02/2006] [Indexed: 05/12/2023]
Abstract
Inoculation with rhizobia or application of Nod factors (lipo-chitooligosaccharides, LCOs) causes transient increases in cytosolic calcium concentration in root hairs of legume plants. We conducted experiments to evaluate whether application of LCO and inoculation with rhizobia improved (45)CaCl(2) uptake into soybean (Glycine max [L.] Merr.) leaves. Roots of soybean seedlings with one developing trifoliolate were immersed in Murashige and Skoog (MS) basal liquid medium containing treatment solutions and (45)CaCl(2), and the plants were incubated under continuous light. After 24 h, leaf samples were taken, and their radioactivity levels were determined. Addition of NodBj-V (C18:1 MeFuc) at a concentration of 10(-7) M increased (45)Ca(2+) uptake. Inoculation with genistein-induced Bradyrhizobium japonicum strain 532C and USDA3 also increased (45)Ca(2+) uptake; whereas, inoculation with strain Bj-168, a nodC-mutant incapable of producing LCO, did not. Rhizobia that do not normally nodulate soybean, i.e. Rhizobium leguminosarum, and Sinorhizobium meliloti did not affect calcium uptake, nor did the tetramer or pentamer of chitosan, or lumichrome. Surprisingly, Rhizobium sp. NGR234, which can nodulate some types of soybean, although without effective N(2)-fixation, also did not affect calcium uptake. This work suggests that the rhizobial symbiosis, in addition to its known role in provision of nitrogen fixation, also improves early calcium uptake into soybean plants.
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Affiliation(s)
- S Supanjani
- Department of Plant Science, McGill University, Macdonald Campus, Sainte Anne de Bellevue, Que, Canada
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36
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Gray EJ, Lee KD, Souleimanov AM, Di Falco MR, Zhou X, Ly A, Charles TC, Driscoll BT, Smith DL. A novel bacteriocin, thuricin 17, produced by plant growth promoting rhizobacteria strain Bacillus thuringiensis NEB17: isolation and classification. J Appl Microbiol 2006; 100:545-54. [PMID: 16478494 DOI: 10.1111/j.1365-2672.2006.02822.x] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS The aim of this study was to identify and characterize a compound produced by the plant growth promoting bacterium, Bacillus thuringiensis non-Bradyrhizobium Endophytic Bacterium 17. METHODS AND RESULTS The bacterial peptide was analysed and purified via HPLC. Using the disk diffusion assay this peptide inhibited the growth of 16/19 B. thuringiensis strains, 4/4 Bacillus cereus strains, among others, as well as a Gram-negative strain Escherichia coli MM294 (pBS42). Both bactericidal and bacteristatic effects were observed on B. cereus ATCC 14579 and bactericidal effects were observed on B. thuringiensis ssp. thuringiensis Bt1267. The molecular weight of the peptide was estimated via SDS-PAGE and confirmed with Matrix Assisted Laser Desorption Ionization Quadrapole Time of Flight mass spectrometry; its weight is 3162 Da. The peptide is biologically active after exposure to 100 degrees C for 15 min, and within the pH range 1.00-9.25. Its activity disappeared when treated with proteinase K and protease, but not with alpha-amylase or catalase. CONCLUSIONS We conclude that this is the first report of a bacteriocin produced by a plant growth promoting rhizobacteria (B. thuringiensis) species and have named the bacteriocin thuricin 17. SIGNIFICANCE AND IMPACT OF THE STUDY Our work has characterized a bacteriocin produced by a plant growth promoting bacterium. This strain is previously reported to increase soya bean nodulation.
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Affiliation(s)
- E J Gray
- Department of Plant Science, McGill University-Macdonald Campus, St Anne-de-Bellevue, QC, Canada
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Affiliation(s)
- Kyung Dong Lee
- Department of Dentistry, College of Medicine, Yeungnam University, Daegu, Korea
| | - Hee Kyung Lee
- Department of Dentistry, College of Medicine, Yeungnam University, Daegu, Korea
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Ha TJ, Jang DS, Lee JR, Lee KD, Lee J, Hwang SW, Jung HJ, Nam SH, Park KH, Yang MS. Cytotoxic effects of sesquiterpene lactones from the flowers ofHemisteptia lyrata B. Arch Pharm Res 2003; 26:925-8. [PMID: 14661858 DOI: 10.1007/bf02980201] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Four guaia-12,6-olide type sesquiterpene lactones, aguerin B (1), 8alpha-acetoxyzaluzanin C (2), cynaropicrin (3), and deacylcynaropicrin (4), were isolated from the flowers of Hemisteptia lyrata Bunge. It is the first report on the isolation of compounds 1-4 from Hemisteptia species. All the isolates (1-4) were examined for their cytotoxic activity against SK-OV-3, LOX-IMVI, A549, MCF-7, PC-3, and HCT-15 human cancer cell lines.
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Affiliation(s)
- Tae Joung Ha
- Institute of Agriculture and Life Science, Gyeongsang National University, Chinju 660-701, Korea
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Lee KD, Yang MS, Ha TJ, Park KM, Park KH. Isolation and identification of dihydrochrysanolide and its 1-epimer from Chrysanthemum coronarium L. Biosci Biotechnol Biochem 2002; 66:862-5. [PMID: 12036063 DOI: 10.1271/bbb.66.862] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
A new sesquiterpene lactone (1) was isolated with known dihydrochrysanolide derivatives (2 and 3) from the flowers of Chrysanthemum coronarium L., and their structures were identified by spectroscopic data. The stereochemistry of the epimers (1 and 2) was determined from NOESY data and an X-ray crystallographic analysis. The isolated compounds (1-3) were examined for their cytotoxic activity against such human cell lines as A549, PC-3 and HCT-15.
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Affiliation(s)
- Kyung Dong Lee
- Department of Agricultural Chemistry, Gyeongsang National University, Chinju, Korea
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Hun Park K, Joung Ha T, Suk Yang M, Pak Y, Rok Lee J, Dong Lee K, Mook Kim H. New Guaiane-Type Sesquiterpene Lactones from Hemisteptia lyrata Bunge. HETEROCYCLES 2002. [DOI: 10.3987/com-01-9387] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Abstract
[reaction: see text]. A new fluorescent chemosensor, anthryl tetra acid, was synthesized and showed large fluorescence quenching effects in 100% aqueous solution with metal ions via photoinduced electron transfer (PET). Chelatoselective fluorescence perturbation was observed with Cd(II) and resulted from electrophilic aromatic cadmiation.
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Affiliation(s)
- M Choi
- Department of New Materials Chemistry and Nanophotonics Research Center, Silla University, Pusan 617-736, Korea
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Abstract
Biodegradable microspheres containing recombinant human epidermal growth factor (rhEGF) were prepared using poly(L-lactic acid) by a solvent evaporation method based on multiple w/o/w emulsion. Encapsulation efficiency and initial release were influenced by the amount of polymer, inner water phase volume and osmotic pressure difference between inner water phase and outer water phase. The effect of osmotic pressure difference between inner water phase and outer water phase in w/o/w emulsion on particle size, porosity and in vitro release of rhEGF from microspheres were also studied. Microspheres prepared with the optimized osmotic pressure, polymer amount and inner water volume produced 21% initial release on the first day with 92% encapsulation efficiency. The blood concentration of rhEGF was maintained at constant levels for 9-11 days after a single subcutaneous (s.c.) administration of rhEGF microspheres. The gastric ulcer healing effect of a single s.c. administration of rhEGF microspheres was increased 1.44-fold compared with twice a day s.c. administration of rhEGF saline solution after 11 days. The enhanced curative ratio of rhEGF loaded microspheres may be due to the optimized osmotic pressure, high encapsulation efficiency and sustained release pattern.
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Affiliation(s)
- K Han
- College of Pharmacy, Chungbuk National University, Cheongju, 361-763, Chungbuk, South Korea.
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43
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Abstract
Acori graminei Rhizoma (AGR) is shown to exhibit a number of pharmacological actions including sedation and anticonvulsive action. To further characterize its actions in the CNS, the present study evaluated the effects of essential oils (EO) from AGR on the excitotoxic neuronal cell death induced in primary rat cortical cell cultures. EO inhibited the glutamate-induced excitotoxicity in a concentration-dependent manner, with the IC50 of 0.241 mg/ml. EO exerted more potent neuroprotection against the toxicity induced by NMDA (IC50 = 0.139 mg/ml). In contrast, the AMPA-induced toxicity was not inhibited by EO. Receptor-ligand binding studies were performed to investigate the neuroprotective action mechanism. EO dramatically inhibited the specific bindings of a use-dependent NMDA receptorion channel blocker [3H]MK-801, indicating an NMDA receptor antagonist-like action. However, the bindings of [3H]MDL 105,519, a ligand selective for the glycine binding site of NMDA receptor, were not considerably inhibited. These results demonstrated that EO extracted from AGR exhibited neuroprotective effects on cultured cortical neurons through the blockade of NMDA receptor activity, and that the glycine binding site appeared not to be the major site of action.
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Affiliation(s)
- J Cho
- Department of Pharmacology, College of Medicine, Dongguk University, Kyongju, Kyongbuk, Korea.
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Cho J, Joo NE, Kong JY, Jeong DY, Lee KD, Kang BS. Inhibition of excitotoxic neuronal death by methanol extract of Acori graminei rhizoma in cultured rat cortical neurons. J Ethnopharmacol 2000; 73:31-37. [PMID: 11025136 DOI: 10.1016/s0378-8741(00)00262-2] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Acori graminei rhizoma (AGR) are reported to exhibit a number of pharmacological actions in the central nervous system. The effects of the methanol extract of AGR on excitotoxic neuronal death were evaluated in the present study using cultured rat cortical neurons. Based on the phase-contrast microscopic examinations of cultures and lactate dehydrogenase activities measured in the culture media, the glutamate-induced excitotoxicity was significantly inhibited by the extract. The inhibitory action of the extract was more potent and selective for the N-methyl-D-aspartate (NMDA) receptor-mediated toxicity. The AGR extract competed with [3H]MDL 105,519 for the specific binding to the glycine site of the NMDA receptor with the IC(50) value of 164.7 microg/ml. Modulation of the NMDA receptor activity by the extract was determined using [3H]MK-801 binding studies. The reduction of the binding in the presence of the extract indicated the receptor inactivation by AGR. These results demonstrated that the methanol extract of AGR exhibited protective action against excitotoxic neuronal death, and that the neuroprotective action was primarily due to the blockade of NMDA receptor function by the interaction with the glycine binding site of the receptor.
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Affiliation(s)
- J Cho
- Department of Pharmacology, College of Medicine, Dongguk University, 780-714, Kyongju, South Korea.
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Abstract
We have cloned the genomic sequence coding for the high mobility group 1 (HMG1) protein in chickens. Multiple sequence alignment shows that the chicken HMG1 gene is highly homologous to the human and the mouse HMG1 genes. The gene structure of chicken HMG1 is similar to that of the mouse and the human HMG1 genes, with the same exon-intron boundaries. However, in contrast to other avian genes that have shorter introns, the chicken HMG1 gene has introns that are twice as long as their mammalian homologues. In addition to the functional, intron-containing HMG1 gene, all mammalian genomes contain more than 50 copies of HMG1 retropseudogenes each, while in the chicken genome there are no HMG1 retropseudogenes. This finding suggests that the HMG1 retropseudogenes arose in mammals after their divergence away from the birds.
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Affiliation(s)
- H K Lum
- Department of Applied Biology and Chemical, Technology, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
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46
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Abstract
Advances in our understanding of fundamental cell biological processes have facilitated an expansion of therapeutic approaches to altering cellular physiology and phenotype. As many of these methods involve macromolecular agents that act on targets within the nucleus or cytoplasm, achieving their full potential ultimately requires the efficient delivery of these agents across the cell membrane barrier into the cytosol. Various strategies have been employed to enhance cytosolic delivery. These include either directly penetrating the plasma membrane, or avoiding degradation within the hydrolytic environment of the endosomal/lysosomal pathway after endocytic uptake. Some of the more promising methods in this regard have exploited the mechanisms utilized by certain viruses and bacteria for escaping into their host cell's cytosol. In this review, we will discuss some of these methods with an emphasis on the use of pore-forming proteins from bacteria. Particular attention will be drawn to the pH-sensitive endosomolytic bacterial hemolysins, such as listeriolysin O, and the potentiol for their use in cytosolic drug delivery systems.
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Affiliation(s)
- C J Provoda
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Michigan, Ann Arbor, MI 48109-1065, USA
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Lee KD, Chang HK, Jo YK, Kim BS, Lee BH, Lee YW, Lee HK, Huh MH, Min YG, Spagnoli GC, Yu TH. Expression of the MAGE 3 gene product in squamous cell carcinomas of the head and neck. Anticancer Res 1999; 19:5037-42. [PMID: 10697507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
BACKGROUND The melanoma antigen (MAGE) 3 gene may be a useful tumor specific marker since it is expressed in a variety of cancers. MATERIALS & METHOD The expression and intracellular location of MAGE 3 gene product were investigated in 40 squamous cell carcinomas, 2 tumor lines, 20 benign diseases, and 20 normal tissues of the head and neck. Immunohistochemical staining with anti-MAGE 3 mAb 57B was conducted from fresh frozen specimens. Correlations between MAGE 3 expression and clinicopathological parameters were also evaluated. RESULTS The MAGE 3 gene product was detected in squamous cell carcinomas (18/40, 45%) and in tumor cell lines (2/2, 100%), but not in benign diseases and normal tissues. No significant correlation was drawn between MAGE 3 expression and clinical parameters including clinical stages and metastasis. CONCLUSION These results show MAGE 3 antigen could represent a potential target for immunotherapy in head and neck squamous cell carcinomas.
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Affiliation(s)
- K D Lee
- Department of Otolaryngology, Kosin University College of Medicine, Pusan, Korea
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Blazer-Yost BL, Păunescu TG, Helman SI, Lee KD, Vlahos CJ. Phosphoinositide 3-kinase is required for aldosterone-regulated sodium reabsorption. Am J Physiol 1999; 277:C531-6. [PMID: 10484339 DOI: 10.1152/ajpcell.1999.277.3.c531] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Aldosterone, a steroid hormone, regulates renal Na+ reabsorption and, therefore, plays an important role in the maintenance of salt and water balance. In a model renal epithelial cell line (A6) we have found that phosphoinositide 3-kinase (PI 3-kinase) activity is required for aldosterone-stimulated Na+ reabsorption. Inhibition of PI 3-kinase by the specific inhibitor LY-294002 markedly reduces both basal and aldosterone-stimulated Na+ transport. Further, one of the products of PI 3-kinase, phosphatidylinositol 3,4,5-trisphosphate, is increased in response to aldosterone in intact A6 monolayers. This increase occurs just before the manifestation of the functional effect of the hormone and is also inhibited by LY-294002. With the use of blocker-induced noise analysis, it has been demonstrated that inhibition of phosphoinositide formation causes an inhibition of Na+ entry in both control and aldosterone-pretreated cultures by reducing the number of open functional epithelial Na+ channels (ENaCs) in the apical membrane of the A6 cells. These novel observations indicate that phosphoinositides are required for ENaC expression and suggest a mechanism for aldosterone regulation of channel function.
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Affiliation(s)
- B L Blazer-Yost
- Biology Department, Indiana University, Purdue University at Indianapolis, Indianapolis 46202, Indiana, USA.
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49
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Abstract
The "evolution" of a thing, a custom, an organ is thus by no means its progressus toward a goal, even less a logical progressus by the shortest route and with the least expenditure of force, but a succession of more or less profound, mutually independent processes of subduing, plus the resistances they encounter, the attempts at transformation for the purpose of defense and reaction, and the results of successful counteractions. The form is fluid, but the "meaning" is even more so.
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Affiliation(s)
- G M Larson
- Pharmaceutics Division, College of Pharmacy, University of Michigan, Ann Arbor 48019-1065, USA
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50
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Hyman IA, Wojtowicz A, Lee KD, Haffner ME, Fiorello CA, Storlazzi JJ, Rosenfeld J. School-based methylphenidate placebo protocols: methodological and practical issues. J Learn Disabil 1998; 31:581-614. [PMID: 9813957 DOI: 10.1177/002221949803100609] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Around 1990, psychologists and educators began to notice increasing use of methylphenidate by students. Diagnosis of attention-deficit/hyperactivity disorder by family physicians and pediatricians was most commonly based on brief behavioral descriptions by parents and, infrequently, by use of rating scales. At that time, the present researchers began to explore the development of a school-based, methodologically sound, and inexpensive method of assessing the efficacy of stimulant medications, which would ensure reasonable compliance by teachers, parents, and students in monitoring the effects of medications and placebos. This article focuses on the methodological issues involved in choosing instruments to monitor behavior, once a comprehensive evaluation has suggested trials on Ritalin. Case examples illustrate problems of teacher compliance in filling out measures, supplying adequate placebos, and obtaining physician cooperation, and with the practical issue of providing adequate data without overwhelming the time and resources of participants. Emerging school-based methodologies are discussed with recommendations for future efforts.
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Affiliation(s)
- I A Hyman
- School Psychology, Temple University, Philadelphia, PA 19122, USA
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