• The Korean Journal of Nuclear Medicine
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• v.31 no.4
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• pp.421-426
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• 1997

We evaluated the in vivo kinetics, distribution, and pharmacology of N-(4-[$^{18}F$]fluoromethylbenzyl)spiperone ([$^{18}F$]FMBS), a newly developed derivative of spiperone, as a potentially more selective radiotracer for the dopamine (DA) $D_2$ receptors. Mice received 1.9-3.7 MBq (1.8-3.6 nmol/kg) of [$^{18}F$]FMBS by tail vein injection. The time course and regional distribution of the tracer in brain were assessed. Blocking studies were carried out by intravenously preinjecting DA $D_2$ receptor blockers (spiperone, butaclamol) as well as drugs with high affinity for DA $D_1$ (SCH 23390), DA transporter (GBR 12909), and serotonin $S_2$ ($5-HT_2$) (ketanserin) sites. After injection of the tracer, the radioactivity in striatum increased steadily over time, resulting in a striatal-to-cerebellar ratio of 4.8 at 120 min postinjection. By contrast, the radioactivity in cerebellum, frontal cortex, and remaining cortex washed out rapidly. Preinjection of unlabeled FMBS (1 mg/kg) and spiperone (1 mg/kg) reduced [$^{18}F$]FMBS striatal-to-cerebellar ratio by 41% and 80%, respectively. (+)-Butaclamol (1 mg/kg) blocked 80% of the striatal [$^{18}F$]FMBS binding, while (-)-butaclamol (1 mg/kg) did not. Preinjection of SCH 23390 (1 mg/kg) and GBR 12909 (5 mg/kg) had no significant effect on [$^{18}F$]FMBS binding. Ketanserin (1 mg/kg), a ligand for the $5-HT_2$ receptors, did not cause significant inhibition either in striatum, in frontal cortex, or the remaining cortex. The results demonstrate that [$^{18}F$]FMBS labels DA $D_2$ receptors selectively in vivo in the mouse brain. It may hold promise as a selective radiotracer for studying DA $D_2$ receptors in vivo by PET.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.6
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• pp.672-677
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• 2001

There was an outbreak of food poisoning due to eating well-cooked imported tropical fish, Stromateus stellatus on May, 2000, in Korea. Gastrointestinal symptoms such as diarrhea ($92\%$), nausea ($77\%$), abdominal pain ($54\%$), vomiting ($46\%$) and headache ($23\%$) were experienced within $0.5\~2$ hours (median 1 hour) after eating, Any specific natural toxins were not confirmed concerned to those poisoning, but large amount of abnormal lipid ($23\%$) was found from the muscle such as 1-O-diacyl glyceryl ethers (DAGE), which was consisted of $61.8\%$ of total lipid. The 16:0 ($66.3\%$) and 18:1 ($15.8\%$) alkyl chains were dominant in all alkyl chains of DAGE which were presumed as the causative agent for the diarrheal food poisoning. O1eic acid (18:1) was found as a major fatty acid at the sn-2 or 3 in DAGEs. O-16:0-18:1-18:1 ($16.2\%$),O-16:0-18:1-22:1 ($14.7\%$) and O-18:0-18:1-22:1 ($11.0\%$) were contained as the major molecular species of DAGEs by RI-HPLC.

• Journal of Ginseng Research
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• v.43 no.2
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• pp.209-217
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• 2019

Background: Ginseng is a traditional herbal medicine for human health. Ginseng contains a bioactive ligand named gintonin. The active ingredient of gintonin is lysophosphatidic acid C18:2 (LPA C18:2). We previously developed a method for gintonin-enriched fraction (GEF) preparation to mass-produce gintonin from ginseng. However, previous studies did not show the presence of other bioactive lipids besides LPAs. The aim of this study was to quantify the fatty acids, lysophospholipids (LPLs), and phospholipids (PLs) besides LPAs in GEF. Methods: We prepared GEF from white ginseng. We used gas chromatography-mass spectrometry for fatty acid analysis and liquid chromatography-tandem mass spectrometry for PL analysis, and quantified the fatty acids, LPLs, and PLs in GEF using respective standards. We examined the effect of GEF on insulin secretion in INS-1 cells. Results: GEF contains about 7.5% linoleic (C18:2), 2.8% palmitic (C16:0), and 1.5% oleic acids (C18:1). GEF contains about 0.2% LPA C18:2, 0.06% LPA C16:0, and 0.02% LPA C18:1. GEF contains 0.08% lysophosphatidylcholine, 0.03% lysophosphatidylethanolamine, and 0.13% lysophosphatidylinositols. GEF also contains about 1% phosphatidic acid (PA) 16:0-18:2, 0.5% PA 18:2-18:2, and 0.2% PA 16:0-18:1. GEFmediated insulin secretion was not blocked by LPA receptor antagonist. Conclusion: We determined four characteristics of GEF through lipid analysis and insulin secretion. First, GEF contains a large amount of linoleic acid (C18:2), PA 16:0-18:2, and LPA C18:2 compared with other lipids. Second, the main fatty acid component of LPLs and PLs is linoleic acid (C18:2). Third, GEF stimulates insulin secretion not through LPA receptors. Finally, GEF contains bioactive lipids besides LPAs.

• Korean Journal of Microbiology
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• v.29 no.5
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• pp.284-289
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• 1991

the nucleotide sequence of the 3' terminal 568 bases of the 18S rRNA gene from Mucor racemosus was determined. The 3' end of the structural gene was identified by comparison with the published sequence for the Saccharomyces cerevisiae gene. The M. racemosus gene was found to share 83.8% homology with that of S. cerevisiae and 71-81% homology with those of human, mouse, maize, Xenopus laevis and Tetrahymena thermophila. The known methylation sites in X. laevis and human were also highly conserved in M. racemosus and located within most conserved regions of 18S RNA gene throughout evolution.

• Clinical and Experimental Pediatrics
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• v.52 no.11
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• pp.1234-1240
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• 2009

Purpose:Enteroviruses (EVs) are commonly known to cause infection, especially in infants and children. This report presents an overview of enterovirus epidemiology in central Korea. Methods:From the spring of 2005 to the autumn of 2006, we collected the cerebrospinal fluid (CSF) and stool samples from the pediatric patients with a febrile illness or suspected meningitis who were admitted to hospitals in central Korea. In order to test for EVs, cell lines were derived from pretreated susceptible specimen, and the cytopathic effects were observed. Seminested real time-polymerase chain reaction (RT-PCR) and direct sequencing were performed for genotypic and phylogenetic analyses. Results:Of the 305 patients examined, 51 (16.7%) tested positive for EV. Of these 51 patients, 44 showed the following serotypes: Echovirus (ECV) 18 (18 cases, 35.2%), Coxsackievirus B (CVB) 5 (13 cases, 25.4%), ECV25 (5 cases, 9.8%), ECV9 (4 cases, 7.8%), ECV5 (3 cases, 5.8%), and EV74 (1 case, 1.9%). In 2005, between June and August, ECV18 and CVB5 were mostly responsible for the enteroviral infections among the patients in central Korea. In 2006, between July and August, ECV25 was mostly the cause of enteroviral infection. Conclusions:There is a need for continuous surveillance of enteroviral infection and its clinical manifestations, particularly for EV74, which was first identified in Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.36 no.6
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• pp.513-520
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• 1991

The objective of experiment was to investigate the effects of seeding rate on forage yield and feed value, and to clarify the optimum seeding rate of rye in middle west area when cultured in paddy field. The field experiment treated with 5 levels of seeding rate was carried out at Yesan area in 1989. The plant height and the number of tillers per m' were increased but the dry matter rate was decreased as seeding rate increased. The fresh and dry weights of rye plant were increased as seeding rate increased. The highest yield was obtained from the harvest of May 15 and 25 in Yesan area. The TDN content and RFV were decreased by the increased seeding rate and delayed cutting date. The highest TDN yield was obtained from the seeding rate of 18kg/l0a and the next highest yield was obtained from the 23kg and 28kg/l0a seeding rate. The content of ENE, NEL, NEM, and NEG was decreased by the increased seeding rate and delayed cutting date. The highest ENE and NEL yields were obtained from the seeding rate of 23kg/l0a and May 15 harvest. The highest NEM and NEG yields were obtained from the seeding rates of 18kg/l0a and May 15 harvest, and of 18-28kg/l0a and May 5 harvest, respectively.

• Journal of the Korean Home Economics Association
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• v.30 no.4
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• pp.77-88
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• 1992

To investigate the oxidative stabilities of the ${\gamma}$-ray irradiated soybean during storage and heating and some physico-chemical characteristics of soybean and the extracted soybean oil (SBO) with/without the ${\gamma}$-ray irradiation were determined. The ${\gamma}$-ray level use in irradiation for soybean were 2.5, 5.0 and 10.0 KGY respectively and Acid Value, Peroxide Value, Conjugated Diene Value, Composed Fatty Acids amounts, and Trans Fatty Acid occurrence were determined for all samples, which were incubated at 45$\pm$1$^{\circ}C$ for 25 days heated at 180$\pm$1$^{\circ}C$ for 30 hours. And these values of the ${\gamma}$-ray treated samples were compared to those of nontreated samples. The results were obtained as follows : 1. According to the increased level of the ${\gamma}$-ray irradiation, there was little difference in Dielectric Constant, Viscosity, and the Induction Period by Rancimat. But, in case of 5.0 KGY, oxidative stability was increased more twice than that of non-irradiation. In the quantity of fatty Acids composition of the extracted soybean oil irradiated with 10.0 KGY, palmitic, oleic and linoleic acids were less increased thanb those of non-irradiation, while stearic, linolenic acids were decreased. In the case of 2.5 KGY irradiation, stearic and oleic acids were increased. 2. The Acid Value of SBO according to the ${\gamma}$-ray irradiation level was almost not change, but was 0.1 lower than that of non-irradiation during incubation (45$\pm$1$^{\circ}C$). The Peroxide Value of SBO with the ${\gamma}$-ray irradiation, was very lower than that of non-irradiation, but its effect on oxidative stability was better of SBO treated with 5.0 KGY and 10.0 KGY. In the Fatty Acids composition of SBO, palmitic, stearic, oleic acids were increased, while linoleic, linolenic acids were decreased during incubation(45$\pm$1$^{\circ}C$). This tendency was more obvious due to the ${\gamma}$-ray level. While heating(180$\pm$1$^{\circ}C$), the Acid Value of SBO treated with the ${\gamma}$-ray irradiation was decreased, the Acid Value of SBO irradiated with 2.5 KGY was the lowest. Also the peroxide Values of SBO treated with 5.0 KGY, 10.0 KGY were very lower than that of non-irradiation. Conjugated Diene Value of SBO was almost unchanged according to the ${\gamma}$-level and heating time. 3. When the methyl linoleate was irradiated with the ${\gamma}$-ray, the Trans Fatty Acid was little produced. In case of SBO with non-irradiation, the trans C18:1 was occured about 6.5~7.9%, but trans C18:2 and C18:3 were not shown, while SBO irradiated with the ${\gamma}$-ray 2.5, 5.0, 10.0 KGY, trans C18:3 and C18:2 amount in SBO were increased according to heating time, but trans C18:3 was little occured. As these results, the effects of the ${\gamma}$-ray irradiation to oil containing food were to cut down the energy for food storage and to increase oxdative stability during storge. And also it was shown to be the best that 10.0 KGY of the ${\gamma}$-ray irradiation would be applied to soybean.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.18 no.10
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• pp.896-901
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• 2005

The microstructure and electrical properties of praseodymium-based zinc oxide varistors were investigated at various cobalt oxide contents in the range of $0.5{\~}5.0 mol\%$. The ceramic density increased in the range of $5.25{\~}5.55 g/cm^3$ with increasing cobalt oxide content. The varistor doped with cobalt oxide of $1.0 mol\%$ exhibited the highest nonlinearity, with 66.6 in nonlinear exponent and 1.2 $\mu$A in leakage current. The donor concentration, density of interface states, and tamer height were in the range of $(1.06{\~}1.69){\times}10^{18}/cm^3$, $(3.11 {\~}3.56){\times}10^{12}/cm^2$, and 0.80${\~}$1.07 eV, respectively.

• Journal of Species Research
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• v.11 no.4
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• pp.287-295
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• 2022

Three oxytrichid ciliates, Oxytricha lithofera Foissner, 2016, Pleurotricha curdsi (Shi et al., 2002) Gupta et al., 2003 and Sterkiella tetracirrata Kumar et al., 2015, were isolated from soils and confirmed as new to South Korea. Oxytricha lithofera was identified based on lithosomes, cortical granules, 21-33 adoral zone membranelles, one left (14-21 cirri) and one right (15-18) marginal rows and 5 transverse cirri. Pleurotricha curdsi was identified based on the possession of 2 macronuclear nodules, 2-3 micronuclei, 46-53 adoral zone membranelles, 3 frontal cirri, 5 frontoventral cirri, 5-7 postoral ventral cirri, 2-3 right marginal rows and 5 transverse cirri. Sterkiella tetracirrata was identified with respect 4 macronuclear nodules, 3-6 micronuclei, 25-40 adoral zone membranelles, 3 frontal cirri, 3 postoral ventral cirri, 2 pretransverse cirri, one left (21-30 cirri) and one right (24-30) marginal row and 4 transverse cirri. On the basis of 18S rDNA sequence analyses, we describe the phylogenetic positions of the three species.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.68-75
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• 1991

The seed oil of Ternstroemia gymnanthera. a species of the Ternstroemiaceae, is mainly composed of triglyceride(92.4%), followed by polar lipids(5.9%), sterol(1.2%) and pigments(0.5%). This oil contains 4.8% of cis-11, 12-methylene octadecanoic acid(lactobacillic acid) in the fatty acid composition of the total oil. This identification is based on information from non-urea inclusion formation, silver nitrate impregnated silica gel column and gas liquid chromatography, $^1H-&\;^{13}C-nuclear$ magnetic resonance and mass spectroscopy. Smaller amounts(0.1%) of presumptive 9, 10-methylene hexadecanoic acid(dihydro malvalic acid) is also detected. The major fatty acids in this oil are C18 : 1(36.1%), C18: 2(30.9%), C16: 0(15.1%), C16: 1(7.6%) and C18: 0(3.4%).