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Kim D, Jeon J, Park JD, Sun XG, Gao X, Lee HN, MacManus-Driscoll JL, Kwon DH, Lee S. Stable Supercapacity of Binder-Free TiO 2(B) Epitaxial Electrodes for All-Solid-State Nanobatteries. Nano Lett 2023; 23:6815-6822. [PMID: 37499099 DOI: 10.1021/acs.nanolett.3c00596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Owing to its pseudocapacitive, unidimensional, rapid ion channels, TiO2(B) is a promising material for application to battery electrodes. In this study, we align these channels by epitaxially growing TiO2(B) films with the assistance of an isostructural VO2(B) template layer. In a liquid electrolyte, binder-free TiO2(B) epitaxial electrodes exhibit a supercapacity near the theoretical value of 335 mA h g-1 and an excellent charge-discharge reproducibility for ≥200 cycles, which outperform those of other TiO2(B) nanostructures. For the all-solid-state configuration employing the LiPON solid electrolyte, excellent stability persists. Our findings suggest excellent potential for miniaturizing all-solid-state nanobatteries in self-powered integrated circuits.
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Affiliation(s)
- Dongha Kim
- Department of Physics and Chemistry and Department of Emerging Materials Science, DGIST, Daegu 42988, Republic of Korea
| | - Jingyeong Jeon
- Department of Physics and Chemistry and Department of Emerging Materials Science, DGIST, Daegu 42988, Republic of Korea
| | - Joon Deok Park
- Center for Energy Materials Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Xiao-Guang Sun
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Xiang Gao
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Ho Nyung Lee
- Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Judith L MacManus-Driscoll
- Department of Materials Science and Metallurgy, University of Cambridge, 27 Charles Babbage Road, Cambridge CB3 0FS, United Kingdom
| | - Deok-Hwang Kwon
- Center for Energy Materials Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea
| | - Shinbuhm Lee
- Department of Physics and Chemistry and Department of Emerging Materials Science, DGIST, Daegu 42988, Republic of Korea
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Bae HS, Kang IG, Lee SG, Eom SY, Kim YD, Oh SY, Kwon HJ, Park KS, Kim H, Choi BS, Yu IJ, Park JD. Arsenic exposure and seafood intake in Korean adults. Hum Exp Toxicol 2016; 36:451-460. [DOI: 10.1177/0960327116665673] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Arsenic (As) is widely distributed in the environment, and humans can be exposed to As from various sources such as air, water, soil, and food. This study was performed to evaluate the As exposure levels in Korean adults by measuring total As in urine and its relation with the consumption of seafood, a favorite food in Korea. A total of 2077 adults were the study subjects; they ranged in age from 19 to 83, and they were recruited by probability sampling stratified by area, sex, and age. None of the subjects had been exposed to As occupationally. We collected information about the demographic characteristics, lifestyles, and food consumption of study subjects using a questionnaire and followed urine sampling. Diet was assessed in individual interviews using the 24-h recall method. Total As in urine was analyzed using inductively coupled plasma mass spectrometry (PerkinElmer NEXION 300S; Concord, Ontario, Canada). The geometric mean concentration of total As in urine was observed to be 97.6 µg/L and was higher in males (103.9 µg/L) than in females (93.0 µg/L). Total As levels in urine were affected by sex, age, seafood intake, and geographic location. In this study, total As in urine was positively correlated with fish and shellfish consumption, and was mainly determined by As intake through fish and shellfish/grains/flavors. These findings suggest that seafood consumption might be a major contributor to urinary As levels in Korean adults.
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Affiliation(s)
- H-S Bae
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
| | - I-G Kang
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
| | - S-G Lee
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
| | - S-Y Eom
- Department of Preventive Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - Y-D Kim
- Department of Preventive Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - S-Y Oh
- Department of Food and Nutrition, College of Human Ecology, Kyung-Hee University, Seoul, Korea
| | - H-J Kwon
- Department of Preventive Medicine, College of Medicine, Dankook University, Cheonan, Korea
| | - K-S Park
- Advanced Analysis Center, Korea Institute of Science and Technology, Seoul, Korea
| | - H Kim
- Department of Preventive Medicine, College of Medicine, Chungbuk National University, Cheongju, Korea
| | - B-S Choi
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
| | - I-J Yu
- Department of Food and Nutrition, College of Life and Health Sciences, Hoseo University, Asan, Korea
| | - JD Park
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Korea
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Kim DW, Woo HD, Joo J, Park KS, Oh SY, Kwon HJ, Park JD, Hong YS, Sohn SJ, Yoon HJ, Hwang MS, Kim J. Estimated long-term dietary exposure to lead, cadmium, and mercury in young Korean children. Eur J Clin Nutr 2014; 68:1322-6. [PMID: 24961543 DOI: 10.1038/ejcn.2014.116] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2013] [Revised: 03/10/2014] [Accepted: 04/13/2014] [Indexed: 11/09/2022]
Abstract
BACKGROUND Controlling for day-to-day variation is a key issue in estimating long-term dietary exposure to heavy metals using 24-hour recall (24HR) data from a relatively small number of days. OBJECTIVES This study was conducted to estimate long-term dietary exposure to lead, cadmium and mercury among Korean children using the Iowa State University (ISU) method and to assess the contributions of different food groups to heavy metal intake. METHODS We analyzed 2 days of 24HR data from 457 children between 0 and 6 years of age in 2010. Using bootstrapped concentration data for 118 representative foods, 93.5% of total intake was included in the exposure estimates in this study. Using the 2-day exposure data, we estimated long-term exposure by controlling for within-individual variation using the ISU method. RESULTS The long-term dietary exposure estimates (mean±standard deviation) for lead, cadmium, and mercury were 0.47±0.14, 0.38±0.20, and 0.22±0.08 μg/kg bw/day, respectively. For lead and cadmium, the percentages of children whose exposure was greater than the reference value were 35 and 42%, respectively. Fruits were an important source of lead exposure, and cereal and fish and shellfish made the greatest contributions to the total cadmium and mercury exposure. CONCLUSIONS Our findings also suggest that the long-term exposure to lead and cadmium was somewhat greater than the reference values, whereas mercury exposure was well below than the reference value in this population. Further studies may be necessary to evaluate the food items contributing to heavy metal exposure, and continuous monitoring is needed to ensure the safety of food intake and dietary patterns among vulnerable groups in Korea.
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Affiliation(s)
- D W Kim
- Molecular Epidemiology Branch, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
| | - H D Woo
- Molecular Epidemiology Branch, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
| | - J Joo
- Biometric Research Branch, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
| | - K S Park
- Advanced Analysis Center, Research Planning & Coordination Division, Korea Institute of Science and Technology, Seoul, Republic of Korea
| | - S Y Oh
- Department of Food & Nutrition, College of Human Ecology, Kyung Hee University, Seoul, Republic of Korea
| | - H J Kwon
- Department of Preventive Medicine, College of Medicine, Dankook University, Cheonan-si, Chungcheongnam-do, Republic of Korea
| | - J D Park
- Department of Preventive Medicine, College of Medicine, Chung-Ang University, Seoul, Republic of Korea
| | - Y S Hong
- Dong-A University, Regional Cardiocerebrovascular Center, Busan, Republic of Korea
| | - S J Sohn
- Department of Preventive Medicine, Chonnam National University Medical School, Gwangju, Republic of Korea
| | - H J Yoon
- Risk Analysis & Research Division, National Institute of Food and Drug Safety Evaluation, Cheongwon-gun, Chungcheongbuk-do, Republic of Korea
| | - M S Hwang
- Risk Analysis & Research Division, National Institute of Food and Drug Safety Evaluation, Cheongwon-gun, Chungcheongbuk-do, Republic of Korea
| | - J Kim
- Molecular Epidemiology Branch, National Cancer Center, Goyang-si, Gyeonggi-do, Republic of Korea
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Baek NI, Kim JM, Park JH, Ryu JH, Kim DS, Lee YH, Park JD, Kim SI. Ginsenoside Rs(3), a genuine dammarane-glycoside from Korean red ginseng. Arch Pharm Res 2012; 20:280-2. [PMID: 18975165 DOI: 10.1007/bf02976158] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/1997] [Indexed: 11/28/2022]
Abstract
A genuine dammarane-glycoside, named as ginsenoside Rs(3), was isolated from the MeOH extracts of Korean red ginseng (Panax ginseng C.A. Meyer) through repeated silica gel column chromatographies and its chemical structure was determined as (20S)-protopanaxadiol 3-O-[6''-O-acetyl-beta-D-glucopyranosyl (1-->2)-beta-D-glucopyranoside on the basis of several spectral and physical evidences including HMBC and FAB-MS.
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Affiliation(s)
- N I Baek
- College of Industry, Kyung Hee University, Seochun-Ri 1, Kiheung-Eup, Yongin-Si, 449-701, Suwon, Kyunggi-Do, Korea
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Abstract
Cadmium (Cd) is toxic to sensory ganglia in many animal species. Cadmium uptake is low in the central nervous system, but it distributes preferentially to peripheral sensory and autonomic ganglia. Strain differences have been demonstrated in the sensitivity of mice to Cd-induced hepatotoxicity, testicular toxicity, and teratogenicity. To study the sensitivity of different mouse strains to Cd toxicity in sensory ganglia, eight strains of mice (four sensitive to testicular toxicity: 129/SVIM, AKR/J, DBA/1J, and C57BR/J; and four resistant: Balb/C, C3H/HeJ, A/J, and C57BL/6J) were given 15 micromol CdCl(2)/kg iv. Trigeminal ganglia (TG) were harvested 24 h later and examined by light microscopy for pathologic lesions. Cadmium induced degeneration of ganglion cells in five strains, namely 129/SVIM, AKR/J, DBA/1J, C57BR/J, and C3H/HeJ mice. These are the same strains that show sensitivity to testicular toxicity, except for C3H/HeJ, which is resistant to testicular toxicity. Cd also induced focal hemorrhages around the ganglion cells and nerve fibers in two of these strains (129/SVIM and AKR/J) and scattered foci of necrosis in C3H/HeJ and 129/SVIM strains. There was no morphologic abnormality in three strains, namely Balb/C, A/J, and C57BL/6J. To examine the mechanism of these strain differences in toxicity, all eight strains of mice were given a nontoxic dose of Cd (0.4 micromol CdCl(2)/kg, 20 microCi (109)Cd/kg iv). Cadmium distribution to the brain and trigeminal ganglia was determined 30 min later by gamma scintillation spectrometry. Cadmium content in the brain was very low and did not differ among the eight strains. In contrast, Cd content was higher in trigeminal ganglia of four of the five strains showing trigeminal ganglia sensitivity than in the three strains showing resistance. In conclusion, the toxicity of Cd to trigeminal ganglia is different among various strains of mice. This strain difference in toxicity appears to be due, at least in part, to differences in the distribution of Cd to the ganglia, but it is clearly not the only factor.
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Affiliation(s)
- S S Habeebu
- Center for Environmental and Occupational Health, University of Kansas Medical Center, Kansas City, Kansas 66160-7417, USA
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6
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Abstract
Metallothionein (MT) is a small-molecular weight, cysteine-rich protein that binds metals. The protective role of MT in Cd toxicity is well established but its ability to protect against toxicity of other metals remains unclear. In this study, wild-type and MT-I and -II null mice (MT-null mice) were used to determine whether MT is protective against the lethality of not only Cd but also Zn, Cu, Fe, Pb, Hg and As. Following daily subcutaneous administration of an increasing dose of each metal, starting with a low, non-toxic dose, we compared the cumulative median lethal dose (LD(50)) of each metal between wild-type and MT-null mice. The LD(50) of Cd for wild-type mice was 6.9-fold higher than for MT-null mice. The LD(50) of Zn was 2.4-fold higher for wild-type mice than for MT-null mice, and 1.4-fold higher for Cu and As. The LD(50) of Hg was 1.3-fold higher for wild-type mice than for MT-null mice, but this was not statistically significant. No difference in LD(50) values was observed between wild-type and MT-null mice following Pb and Fe administration. These results suggest that MT is an important protein in the cellular defense against Cd toxicity and lethality, but it provides much less protection against the lethality of the other metals.
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Affiliation(s)
- J D Park
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160-7417, USA
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Park KM, Kim YS, Jeong TC, Joe CO, Shin HJ, Lee YH, Nam KY, Park JD. Nitric oxide is involved in the immunomodulating activities of acidic polysaccharide from Panax ginseng. Planta Med 2001; 67:122-126. [PMID: 11301856 DOI: 10.1055/s-2001-11508] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [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
The effects of an acidic polysaccharide isolated from the ethanol-insoluble and water-soluble fraction of Panax ginseng C. A. Meyer on immunomodulating activities were investigated. A high output nitric oxide synthase (iNOS) was shown in female BALB/c mice administered intraperitoneally with the acidic polysaccharide from ginseng. Newly synthesized iNOS protein was also observed in peritoneal macrophages cultured with interferon-gamma and the acidic polysaccharide. Spleen cells from acidic polysaccharide-treated mice did not proliferate in response to concanavalin A, but restored the responsiveness by the cotreatment of NG-monomethyl-L-arginine (NMMA) with concanavalin A. The treatment of mice with aminoguanidine, a specific iNOS inhibitor, alleviated the acidic polysaccharide-induced suppression of antibody response to sheep red blood cells. Present results suggest that the immunomodulating activities of the acidic polysaccharide were mediated by the production of nitric oxide.
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Affiliation(s)
- K M Park
- Korea Ginseng & Tobacco Research Institute, Taejon, Korea
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8
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Abstract
N-(2-Chloroethyl)-N-methylphenylalanine was designed and synthesized in an optically active form as a novel class of mechanism-based inactivator for carboxypeptidase A (CPA). It was anticipated that the chloroethylamino moiety of the CPA bound inhibitor undergoes an intramolecular SN2 reaction to generate a chemically reactive species (an aziridinium ion) which is expectedly subjected to a nucleophilic attack by the carboxylate of Glu-270, leading to covalent modification of the carboxylate. The irreversible nature of the inhibition of CPA by the inhibitor was supported by the kinetic data: the enzyme lost its enzymic activity in a time-dependent manner in the presence of the inhibitor and the inactivated CPA failed to regain the activity upon dialysis. Interestingly, the (R)-isomer that belongs to the D-series was more potent than its enantiomer.
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Affiliation(s)
- J D Park
- Center for Biofunctional Molecules and Department of Chemistry, Pohang University of Science and Technology, South Korea
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9
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Abstract
We provided a curve-fit equation to predict the normal heart weight (g) in Koreans by examining 422 autopsies (215 males and 207 females, from newborn to age 77 yr) who were relatively in good general condition. Heart weight was well correlated with body surface area (m2), body weight (kg), and body height (cm) but poorly with age in both sex. Heart weight progressively increased from birth to the earlier 3rd and 4th decades in male and female, respectively, and then gradually decreased; mean heart weight of all age group was greater in male than in female and significantly different from birth to 4th decade. In both sex, heart weight exponentially increased in accordance with the increase of body height, body weight, and body surface (in male, heart weight=0.00312 x body height(2.239), r2=0.750, p<0.0001; in female, heart weight=0.00443 x body height(2170), r2=0.781, p<0.0001; in male, heart weight=9.22 x body weight(0.853), r2=0.770, p<0.0001; in female, heart weight=9.00 x body weight0.855, r2=0.820, p<0.0001; in male, heart weight=155.18 x body surface area1.290, r=0.808, p<0.0001; in female, heart weight=124.13 x body surface area1.242, r=0.834, p<0.0001). These results indicate that heart weight is better correlated with body surface area than with body weight; however, body weight should be a better determinant of a predicted heart weight, since body surface area is entirely dependent on body height and body weight.
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Affiliation(s)
- J S Seo
- Department of Forensic Medicine, Korea National Institute of Scientific Investigation, Seoul
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10
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Kim YS, Jin SH, Lee YH, Park JD, Kim SI. Differential expression of protein kinase C subtypes during ginsenoside Rh2-lnduced apoptosis in SK-N-BE(2) and C6Bu-1 cells. Arch Pharm Res 2000; 23:518-24. [PMID: 11059834 DOI: 10.1007/bf02976583] [Citation(s) in RCA: 15] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
We examined the modulation of protein kinase C (PKC) subtypes during apoptosis induced by ginsenoside Rh2 (G-Rh2) in human neuroblastoma SK-N-BE(2) and rat glioma C6Bu-1 cells. Apoptosis induced by G-Rh2 in both cell lines was confirmed, as indicated by DNA fragmentation and in situ strand breaks, and characteristic morphological changes. During apoptosis induced by G-Rh2 in SK-N-BE(2) cells, PKC subtypes alpha, beta and gamma were progressively increased with prolonged treatment, whereas PKC delta increased transiently at 3 and 6 h and PKC epsilon was gradually down-regulated after 6 h following the treatment. On the other hand, PKC subtype zeta markedly increased at 24 h when maximal apoptosis was achieved. In C6Bu-1 cells, no significant changes in PKC subtypes alpha, gamma, delta, epsilon and zeta were observed during apoptosis induced by G-Rh2. These results suggest the evidence for a possible role of PKC subtype in apoptosis induced by G-Rh2 in SK-N-BE(2) cells but not in C6Bu-1 cells, and raise the possibility that G-Rh2 may induce apoptosis via different pathways interacting with or without PKC in different cell types.
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Affiliation(s)
- Y S Kim
- Korea Ginseng and Tobacco Research Institute, Youseong-Gu, Taejon.
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11
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Park IK, Lee HS, Lee SG, Park JD, Ahn YJ. Insecticidal and fumigant activities of Cinnamomum cassia bark-derived materials against Mechoris ursulus (Coleoptera: attelabidae). J Agric Food Chem 2000; 48:2528-31. [PMID: 10888580 DOI: 10.1021/jf9904160] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The insecticidal and fumigant activities of Cinnamomum cassia (Blume) bark-derived materials against the oak nut weevil (Mechoris ursulus Roelofs) were examined using filter paper diffusion and fumigation methods and compared to those of the commercially available Cinnamomum bark-derived compounds (eugenol, salicylaldehyde, trans-cinnamic acid, and cinnamyl alcohol). The biologically active constituent of the Cinnamomum bark was characterized as trans-cinnamaldehyde by spectroscopic analysis. In a test with the filter paper diffusion method, trans-cinnamaldehyde showed 100 and 83.3% mortality at rates of 2.5 and 1.0 mg/filter paper, respectively. At 2.5 mg/paper, strong insecticidal activity was produced from eugenol (90.0% mortality) and salicylaldehyde (88. 9%), whereas trans-cinnamic acid revealed moderate activity (73.3%). At 5 mg/paper, weak insecticidal activity (50.0%) was produced from cinnamyl alcohol. In a fumigation test, the Cinnamomum bark-derived compounds were much more effective against M. ursulus larvae in closed cups than in open ones. These results indicate that the insecticidal activity of test compounds was attributable to fumigant action, although there is also significant contact toxicity. As a naturally occurring insect-control agent, the Cinnamomum bark-derived materials described could be useful as a new preventive agent against damage caused by M. ursulus.
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Affiliation(s)
- I K Park
- School of Agricultural Biotechnology, Seoul National University, Suwon Republic of Korea
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Park IK, Lee HS, Lee SG, Park JD, Ahn YJ. Antifeeding activity of isoquinoline alkaloids identified in Coptis japonica roots against Hyphantria cunea (Lepidoptera: Arctiidae) and Agelastica coerulea (Coleoptera: Galerucinae). J Econ Entomol 2000; 93:331-5. [PMID: 10826181 DOI: 10.1603/0022-0493-93.2.331] [Citation(s) in RCA: 3] [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] [Indexed: 05/14/2023]
Abstract
The anti-feeding activity of 3 isoquinoline alkaloids identified from roots of Coptis japonica Makino toward 4th-instar larvae of Hyphantria cunea Drury and adults of Agelastica coerulea Baly was examined using the leaf-dipping bioassay. The biologically active constituents of the Coptis roots were characterized as the isoquinoline alkaloids berberine, palmatine and coptisine by spectroscopic analysis. In a test with H. cunea larvae, the anti-feeding activity was much more pronounced in an application of a mixture of palmatine iodide and berberine chloride (1:1, wt:wt) at 250 ppm (82.3%) and 500 ppm (100%), compared with palmatine iodide (76.0%) and berberine chloride (75.4%) alone at 500 ppm. These results indicate a synergistic effect. With A. courulea adults, berberine chloride showed 57.5 and 91.1% anti-feeding activity at 125 and 250 ppm, respectively; whereas, weak activity was obtained in application of 500 ppm of palmatine iodide (41.4%) and coptisine chloride (52.4%) alone. The Coptis root-derived compounds merit further study as potential insect-control agents.
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Affiliation(s)
- I K Park
- School of Applied Biology & Chemistry and Research Center for New Bio-Materials in Agriculture, College of Agriculture and Life Sciences, Seoul National University, Republic of Korea
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13
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Abstract
In ginsenoside Rh2-treated rat glioma C6Bu-1 cells, apoptotic morphological changes, such as cell shrinkage, chromatin condensation and pyknosis were confirmed by means of electron microscopy. To evaluate whether induction of apoptosis by ginsenoside Rh2 is mediated by the members of Bcl-2 family, we first established C6Bu-1 cells overexpressing Bcl-2. It was demonstrated that the expression of Bcl-2, Bcl-xL and Bax was not altered in ginsenoside Rh2-treated C6Bu-1 cells. Bcl-2 overexpressing C6Bu-1 cells failed to prevent from ginsenoside Rh2-induced cell death. These results suggest the existence of other apoptotic pathway that requires induction of apoptosis by ginsenoside Rh2 rather than the pathway through Bcl-2, Bcl-xL or Bax in C6Bu-1 cells.
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Affiliation(s)
- Y S Kim
- Korea Ginseng and Tobacco Research Institute, Taejon.
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14
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Yu IJ, Lee JY, Chung YH, Kim KJ, Han JH, Cha GY, Chung WG, Cha YN, Park JD, Lee YM, Moon YH. Co-administration of toluene and xylene antagonized the testicular toxicity but not the hematopoietic toxicity caused by ethylene glycol monoethyl ether in Sprague-Dawley rats. Toxicol Lett 1999; 109:11-20. [PMID: 10514026 DOI: 10.1016/s0378-4274(99)00063-6] [Citation(s) in RCA: 16] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Occupational painters are exposed to ethylene glycol monoethyl ether (EGEE), a widely used emulsifying solvent known to cause testicular degeneration and bone marrow depression, together with toluene (TOL) and xylene (XYL) as a mixture. In the previous study (Chung et al., Tox. Lett. 104:143, 1999), testicular atrophy caused by EGEE (200 mg/kg) was shown to be antagonized by co-administration of TOL (250 mg/kg) and XYL (500 mg/kg). This study was conducted to provide histological support for the previously observed antagonistic protective effect of TOL + XYL on EGEE inducible testicular toxicity and to determine whether a similar antagonistic effect can be demonstrated against the EGEE derived hematopoietic toxicity. Compared to the extent of seminiferous tubule degeneration caused by EGEE (150 mg/kg, six times per week for 4 weeks), testes of rats given co-administration of TOL (250 mg/kg) + XYL (500 mg/kg) showed dramatically reduced tubular degeneration. Hyperplasia of Leydig cells in the interstitium was observed in both EGEE and EGEE + TOL + XYL-treated rats. Although a minimal dose of EGEE causing testicular atrophy was used, WBC and platelet counts were decreased significantly. In the TOL + XYL-treated control group, the WBC and platelet counts were not decreased. However, the bone marrow depression caused by EGEE was not reversed by the combined administration of TOL + XYL. In all experimental groups (EGEE alone, TOL + XYL, EGEE + TOL + XYL), plasma levels of creatinine and alkaline phosphatase were significantly decreased. In addition to the marked testicular atrophy, EGEE also decreased the weights of adrenal glands and epididymis. In conclusion, while the testicular degeneration caused by EGEE was antagonized by TOL + XYL, the EGEE derived hematopoietic suppression was not reversed.
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Affiliation(s)
- I J Yu
- Industrial Chemical Research Center, Industrial Safety and Health Research Institute, Korea Industrial Safety Corporation, Taejon, South Korea.
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15
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Kwon BM, Kim MK, Baek NI, Kim DS, Park JD, Kim YK, Lee HK, Kim SI. Acyl-CoA: cholesterol acyltransferase inhibitory activity of ginseng sapogenins, produced from the ginseng saponins. Bioorg Med Chem Lett 1999; 9:1375-8. [PMID: 10360739 DOI: 10.1016/s0960-894x(99)00208-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [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: 10/17/2022]
Abstract
Ginseng sapogenins were produced from ginseng saponins, isolated from Korean ginseng roots. Ginseng saponins very mildly inhibited acyl-CoA:cholesterol acyltransferase (ACAT) in vitro, however, the sapogenins showed strong inhibitory activity on microsomal ACAT. Therefore, the sapogenins will be one of key ingredients of ginseng affected a lowering of the serum total cholesterol level.
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Affiliation(s)
- B M Kwon
- Korea Research Institute of Bioscience and Biotechnology, Yusung, Taejon
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16
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Abstract
A new dammarane glycoside named ginsenoside Rf2 has been isolated from Korean red ginseng (Panax ginseng) and its chemical structure has been elucidated as 6-O-[alpha-L-rhamnopyranosyl (1-->2) beta-D-glucopyranosyl]dammarane-3 beta, 6 alpha, 12 beta, 20(R), 25-pentol by chemical and spectral methods.
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Affiliation(s)
- J D Park
- Korea Ginseng and Tobacco Research Institute, Yousung-Ku Taejon, Korea
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Kim DS, Oh SR, Lee IS, Jung KY, Park JD, Kim SI, Lee HK. Anticomplementary activity of ginseng saponins and their degradation products. Phytochemistry 1998; 47:397-399. [PMID: 9433814 DOI: 10.1016/s0031-9422(97)00580-3] [Citation(s) in RCA: 25] [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] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The anticomplementary activity of ginseng saponins and their degradation products obtained by chemical treatment of Korean red ginseng saponins was investigated. The total saponin and its major components showed strong anticomplementary activity and their structure-activity relationship was evaluated.
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Affiliation(s)
- D S Kim
- Korea Research Institute of Bioscience and Biotechnology, Taejon, Korea
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18
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Abstract
Ginseng saponins and their degradation products have been screened for antagonist activity towards [3H]PAF (platelet activating factor) in washed rabbit platelet receptor binding studies. 20(S)- and delta20-ginsenosides Rg3, protopanaxadiol-type saponins, were found to be relatively potent PAF antagonists (IC50 = 4.9 x 10(-5) M and 9.2 x 10(-5) M, respectively).
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Affiliation(s)
- K Y Jung
- Natural Product Biosynthesis Research Unit, Korea Research Institute of Bioscience & Biotechnology, Taejon
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Yoon BH, Romero R, Jun JK, Park KH, Park JD, Ghezzi F, Kim BI. Amniotic fluid cytokines (interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8) and the risk for the development of bronchopulmonary dysplasia. Am J Obstet Gynecol 1997; 177:825-30. [PMID: 9369827 DOI: 10.1016/s0002-9378(97)70276-x] [Citation(s) in RCA: 403] [Impact Index Per Article: 14.9] [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: 02/05/2023]
Abstract
OBJECTIVE Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth.
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Affiliation(s)
- B H Yoon
- Department of Obstetrics and Gynecology, College of Medicine, Seoul National University, Korea
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20
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Kim HJ, Chun YJ, Park JD, Kim SI, Roh JK, Jeong TC. Protection of rat liver microsomes against carbon tetrachloride-induced lipid peroxidation by red ginseng saponin through cytochrome P450 inhibition. Planta Med 1997; 63:415-418. [PMID: 9342944 DOI: 10.1055/s-2006-957724] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [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
A possible role of cytochrome P450 (P450) inhibition by red ginseng saponins in carbon tetrachloride (CCl4)-induced lipid peroxidation was investigated in liver microsomes prepared from male Sprague Dawley rats. The total saponin of red ginseng standardized on ginsenosides-Rb1, -Rb2, -Rc, -Rd, -Re, and -Rg1 whose composition was studied in our previous report was used in the present study. The standardized saponin of red ginseng showed inhibitory effects on P450-associated monooxygenase activities in a dose-dependent manner, particularly p-nitrophenol hydroxylase activity which has been known to represent CCl4-activating P450 2E1 enzyme. Meanwhile, silymarin enhanced the activity of P450 2E1 enzyme in liver microsomes. When the lipid peroxidation was induced by incubating rat liver microsomes with CCl4 in the presence of NADPH, the standardized saponin significantly blocked the formation of thiobarbituric acid-reactive substances at the same concentrations showing P450 inhibition in liver microsomes. Silymarin revealed more potent protection against CCl4-induced lipid peroxidation. When the lipid peroxidation was induced by FeCl3, in which metabolic activation may not be required, only silymarin could protect the lipid peroxidation in liver microsomes. Taken together, our present results indicated that the inhibitory effects of red ginseng saponin on P450 enzymes may have a critical role in CCl4-induced lipid peroxidation in rat liver microsomes and that the mechanism of hepatoprotection by red ginseng saponin may be distinct from that of silymarin.
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Affiliation(s)
- H J Kim
- Toxicology Research Center, Korea Research Institute of Chemical Technology, Yusung, Taejon, Korea
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21
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Abstract
Doppler waveforms of the human fetal ductus arteriosus and the branch pulmonary artery are distinct in their shape and might reflect fetal cardiovascular hemodynamics and vessel wall characteristics. The waveform of ductus arteriosus had two peaks, a higher one in systole and a lower one in diastole. Both peaks had slow acceleration and deceleration and looked like two narrow base isosceles triangles. This unique waveform might be due to vessel wall characteristics and an instantaneous pressure gradient between the main pulmonary artery and descending aorta. The waveform of the branch pulmonary artery showed very steep acceleration with the onset of ejection followed by steep decline, then low velocity flow during diastole. The characteristic shape of the branch pulmonary artery might be related to high vascular resistance, decreased capacitance and the earlier reflection wave of pulmonary vessels.
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Affiliation(s)
- J Y Choi
- Department of Pediatrics, Seoul National University College of Medicine, Korea
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Jeong TC, Kim HJ, Park JI, Ha CS, Park JD, Kim SI, Roh JK. Protective effects of red ginseng saponins against carbon tetrachloride-induced hepatotoxicity in Sprague Dawley rats. Planta Med 1997; 63:136-140. [PMID: 9140227 DOI: 10.1055/s-2006-957630] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.7] [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
The protective effects of red ginseng saponins against carbon tetrachloride-induced hepatotoxicity were investigated in male Sprague Dawley rats. The total saponins of red ginseng standardized on ginsenosides-Rb1, -Rb2, -Rc, -Rd, -Re, and -Rg1 were used in the present study. The rats were administered the standardized saponins of red ginseng orally at 50, 100, and 200 mg/kg for 7 consecutive days, followed by an administration of carbon tetrachloride at 0.4 ml/kg in corn oil intraperitoneally for 24 h. The administration of saponin changed neither body and organ weights nor hematological and serum clinical parameters. The elevation of SGPT and SGOT activities induced by carbon tetrachloride was partially recovered by the administration of the saponin. The liver vacuolization and lymphoid cell aggregation by carbon tetrachloride were clearly recovered by the red ginseng saponins as examined histologically. The present results indicated that the standardized saponins of red ginseng used in these studies may partially recover the hepatotoxicity induced by carbon tetrachloride in male Sprague Dawley rats.
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Affiliation(s)
- T C Jeong
- Toxicology Research Center, Korea Research Institute of Chemical Technology, Yusung, Taejon, Korea
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Koh YY, Kim YW, Park JD, Oh JW. A comparison of serum haptoglobin levels between acute exacerbation and clinical remission in asthma. Clin Exp Allergy 1996; 26:1202-9. [PMID: 8911708] [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: 02/03/2023]
Abstract
BACKGROUND Bronchial asthma is characterized by airway inflammation, which underlies the phenomenon of bronchial hyperresponsiveness. The concentration of serum haptoglobin (Hp), one of the acute phase reactant proteins, has been reported to correlate with bronchial hyperresponsiveness. The extent to which bronchoconstriction or airway inflammation contributes to airflow obstruction of exacerbation is presumed to determine the responsiveness to the initial bronchodilator therapy. OBJECTIVE To see whether the Hp levels vary with the disease status of asthma, and also to test whether the Hp level at an acute exacerbation (AE) is correlated with the degree of response to initial bronchodilator therapy. METHODS We measured serum Hp levels in 50 children with asthma at the times of an AE and a clinical remission(CR), and analysed the data according to the response to the initial bronchodilator therapy at AE. RESULTS The serum concentration of Hp at AE (228.5 +/- 80.8 mg/dl, mean +/- SD) was significantly (P < 0.01) higher than that at CR (152.3 +/- 49.8 mg/dl) in the total study population. The difference of Hp levels between AE and CR was more marked (101.7 +/- 82.2 mg/dl) in the subjects (n = 19) who responded poorly (post-bronchodilator FEV1 < 75% predicted) to the initial bronchodilator therapy at AE than that (61.0 +/- 56.5 mg/dl) of those (n = 31) who responded well (post-bronchodilator FEV1 > or = 75% predicted). The Hp level at AE correlated with the degree of response to initial bronchodilator therapy (r = (-)0.36, P < 0.05), whereas it had no relationship with the severity of exacerbation (r = 0.04, P = 0.79). CONCLUSION Our results showed that Hp levels may be increased at the time of exacerbation in a given asthma patient. The finding that the elevation of Hp level at AE is more marked in the cases with poor response to initial bronchodilator therapy at AE suggests that the increased Hp level at AE in asthma might reflect the degree of airway inflammation.
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Affiliation(s)
- Y Y Koh
- Department of Pediatrics, Seoul National University Children's Hospital, Korea
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Moon HS, Kim JB, Park JD, Kwon BK, Cho H, Lee HS. Magneto-optic trap of Rb atoms with an injection-seeded laser that operates at two frequencies. Appl Opt 1996; 35:5402-5405. [PMID: 21127538 DOI: 10.1364/ao.35.005402] [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: 05/30/2023]
Abstract
We captured Rb atoms in a magneto-optic trap by using two frequencies in an injection-seeding process of a diode laser without the use of a separate repumping laser. In the incomplete injection-seeding condition, the power of the free-running slave laser at the repumping frequency can be partially converted into power at the master laser frequency, which is stabilized at the cooling frequency. We measured conversion efficiencies and frequency shifts based on the injecting power and the preset frequency difference between the master laser and the slave laser.
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25
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Abstract
A genuine glycoside, named ginsenoside Rh4, was isolated from Korean red ginseng (Panax ginseng C. A. Meyer) through repeated column chromatography, and its chemical structure was established to be 6-O-beta-D-glucopyranosyldammar-20(22),24-diene-3 beta,6 alpha,12 beta-triol by spectral and chemical methods. The stereochemistry of a double bond at C-20(22) of ginsenoside Rh4 was characterized as (E) from a NOESY experiment in the 1H-NMR of the aglycone. Cytotoxic activities of ginsenoside Rh4 and its aglycone against cancer cell lines were evaluated by use of the SRB method.
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Affiliation(s)
- N I Baek
- Korea Ginseng & Tobacco Research Institute, Taejeon, Korea
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Lee YH, Park JD, Baek NI, Kim SI, Ahn BZ. In vitro and in vivo antitumoral phenanthrenes from the aerial parts of Dendrobium nobile. Planta Med 1995; 61:178-180. [PMID: 7753927 DOI: 10.1055/s-2006-958043] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Two phenanthrenes were isolated from the aerial part of Dendrobium nobile Lindl. and their structures were identified to be 4,7-dihydroxy-2-methoxy-9,10-dihydrophenanthrene (1) and denbinobin (2), among which the former has been first isolated from this plant. These two compounds were found to be cytotoxic against A549 (human lung carcinoma), SK-OV-3 (human ovary adenocarcinoma), and HL-60 (human promyelocytic leukemia) cell lines. Compound 1 also showed antitumor activity on the life span of ICR mice intraperitoneally implanted with 1 x 10(6) cells of sarcoma 180.
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Baek NI, Lee YH, Park JD, Kim SI, Ahn BZ. Euonymoside A: a new cytotoxic cardenolide glycoside from the bark of Euonymus sieboldianus. Planta Med 1994; 60:26-29. [PMID: 8134412 DOI: 10.1055/s-2006-959401] [Citation(s) in RCA: 7] [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
A new cytotoxic cardenolide glycoside, euonymoside A (1), was isolated from the bark of Euonymus sieboldianus. The structure of 1 was elucidated as acovenosigenin A-3-O-beta-D-glucopyranosyl (1-->2)-alpha-L-rhamnopyranoside. The IC50 values of 1 against A549 (human lung carcinoma) and SK-OV-3 (human ovary adenocarcinoma) were 0.06 and 0.4 micrograms/ml, respectively.
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Affiliation(s)
- N I Baek
- Laboratory of Natural Products, Korea Ginseng and Tobacco Research Institute, Taejeon, Korea
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Kitagawa I, Zhang RS, Park JD, Baek NI, Takeda Y, Yoshikawa M, Shibuya H. Indonesian medicinal plants. I. Chemical structures of calotroposides A and B, two new oxypregnane-oligoglycosides from the root of Calotropis gigantea (Asclepiadaceae). Chem Pharm Bull (Tokyo) 1992; 40:2007-13. [PMID: 1423756 DOI: 10.1248/cpb.40.2007] [Citation(s) in RCA: 33] [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: 12/27/2022]
Abstract
Two new oxypregnane-oligoglycosides named calotroposides A (1) and B (2) have been isolated from the root of Calotropis gigantea (Asclepiadaceae), an Indonesian medicinal plant, and their chemical structures have been elucidated by chemical and spectroscopic methods as 12-O-benzoyllineolon 3-O-beta-D-cymaropyranosyl(1----4)-beta-D-oleandropyranosyl( 1----4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)-beta-D- cymaropyranoside and 12-O-benzoyldeacetylmetaplexigenin 3-O-beta-D-cymaropyranosyl(1---4)-beta-D-oleandropyranosyl(- ---4)- beta-D-oleandropyranosyl(1----4)-beta-D-cymaropyranosyl(1--- -4)- beta-D-cymaropyranoside, respectively.
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Affiliation(s)
- I Kitagawa
- Faculty of Pharmaceutical Sciences, Osaka University, Japan
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Park JD, Seo DS, McInerney JG, Dente GC, Osiński M. Low-frequency self-pulsations in asymmetric external-cavity semiconductor lasers due to multiple-feedback effects. Opt Lett 1989; 14:1054-1056. [PMID: 19753053 DOI: 10.1364/ol.14.001054] [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: 05/28/2023]
Abstract
We investigate the dynamical stability of external-cavity semiconductor lasers with deliberate tilt asymmetries. Experimentally observed low-frequency self-pulsations are explained by small-signal analysis based on a new rateequation model that uses a time-dependent effective reflectivity to include multiple-feedback effects. We observe and explain the dependence of the self-pulsation frequency on the strength and degree of asymmetry of the feedback, on the injection current, and on the external-cavity length. These results are important in interpreting instabilities, chaos, and other complex dynamical phenomena in external-cavity semiconductor lasers.
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Park HG, Park JD, Lee SS. Pump-intensity-dependent frequency shift in Stokes and anti-Stokes spectra generated by stimulated four-photon mixing in birefringent fiber. Appl Opt 1987; 26:2974-2978. [PMID: 20489997 DOI: 10.1364/ao.26.002974] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
The output spectra of the Stokes and anti-Stokes fields generated by stimulated four-photon mixing in birefringent fiber are investigated both experimentally and theoretically and are found to be dependent on the pump intensity. The pump-intensity-dependent changes in their frequency shifts are measured in 15-m long birefringent fiber by time-resolved spectroscopy using a 500-H(z)Q-switched Nd:YAG laser (lambda = 1.0642microm) as the pump source. Also, the Stokes gain coefficient is calculated as a function of the frequency shift and the pump power for the present phase-matching process where the mutually perpendicular polarization components are involved. The theoretical results agree well with the experimental data obtained.
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Toyoshima H, Park JD. Conduction velocity: an aid in estimating the pathological state of the heart. Int J Cardiol 1983; 3:97-103. [PMID: 6222003 DOI: 10.1016/0167-5273(83)90070-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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