• Parasites, Hosts and Diseases
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• v.22 no.2
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• pp.223-228
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• 1984

Seven cases of surgically proven sparganosis were serologically tested by means of microELISA for their specific IgG antibody levels. For that purpose, crude saline extract of spargana from snake, Natrix tigrina lateralis was prepared and used as antigen. The sparganosis sera were also tested with Paragonimus and Cysticercus antigens to observe the cross reactivity. A total of 71 sera from normal control, ectopic and pulmonary paragonimiasis, clonorchiasis, cysticerCOSIS and Taenia saginata cases were also included. Except for one case of old calcified infection, all of 6 human sparganosis showed higher serum levels of specific IgG antibody when the differential point of positive reaction was set at the absorbance value of 0.25 (the sensitivity being 85.7%). In control and other helminthic infections, all except 3 cases of T. saginata infection showed negative reaction to sparganum antigen (the specificity being 90.7%). None of sparganosis cases showed cress reactivity to Paragonimus and Cysticercus antigens. Undiluted cerebrospinal l1uid also showed high levels of antibody when central nervous system was invaded. The serologic diagnosis by means of micro ELISA could be a useful tool in epidemiological study of human sparganosis in susceptible population, as well as in individual diagnosis.

• Applied Chemistry for Engineering
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• v.19 no.4
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• pp.388-396
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• 2008

2 Components polyurethane coatings are widely used for the industrial coating in general because of its excellent film performance and the workability which were brought by the 3 dimensional cross linked chain structures being formed after the reaction between polyol and polyisocyanate. 2 components polyurethane can be classified into alkyd polyol, polyester polyol, acrylic polyol and polyester modified acrylic polyol depending on where it is used. This research was conducted under the conditions below; different chemical compositions of resin for paint, set the same conditions of viscosity, thinner and acid value, set alternative polyols, OH values and catalysts, set alternative polyisocyanate hardeners of the paint, measure the reaction rates and dynamic mechanical characteristics using RPT-3000, Rotation Rheometer, DMA and FTIR. The research found that the reactivity between polyol and isocyanate influences the film performance and workability depending on the catalysts, OH values and chemical compositions. We find out that different reaction rate of acrylic polyol and polyester modified acrylic polyol with poly-isocyanate is not influenced on temperature and catalyst. In addition, reaction speed of high hydroxyl content polyol is faster than low hydroxyl equivalent. These results can improve difficult working condition to apply urethane coating.

• The Korean Journal of Mycology
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• v.17 no.2
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• pp.66-75
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• 1989

Heterogeneity in antigenic composition of Aspergillus fumigatus isolates from clinical specimens and in antibody response of patients infected with this fungus was investigated by immunoblotting. A considerable quantitative and qualitative difference was found in composition of the culture filtrate antigens derived from a reference strain (ATCC 13073) and 8 clinical isolates of A. fumigatus on SDS-PAGE and immunoblots. The crude CF antigen of a strain AFG7 was selected to identify the serologically reactive and specific components by immunoblotting. Out of more than 36 components separated by electrophoresis, transblotted to nitrocellulose sheet, and reacted with sera that showed a positive reaction to A. fumigatus or other fungal antigens on immunodiffusion tests, merely four or so were found useful to serodiagnosis of aspergillosis. An antigen of 82KD was found most reactive and specific component so as to be contained in the standard preparation. Several other components, for example 11KD, 26KD, 30KD and 31KD, also possessed relatively high reactivity and specificity and seemed to be worth while purifying and characterizing. Antibody binding activity (reactivity) of the antigenic components was clearly shown on immunoblots because some were faintly stained with Coomassie blue but darkly stained on immunoblots, while some others behaved contrary to them. A number of components seemed to carry not only species specific but cross reactive antigenic determinants. Immunoblotting proved very useful to identify serologically reactive and specific components that should be present in the antigen to be employed to the serodiagnosis of aspergillosis.

• The Journal of Korean Medicine
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• v.27 no.3 s.67
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• pp.38-50
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• 2006

Objectives: The aim of this study was to evaluate the effects of Korean ginseng (KG), Korean red ginseng (KRG) and fermented Korean red ginseng (FKRG) extracts on cerebral hemodynamics and to compare distinction of each extract. Methods: Ten healthy male volunteers $(26.0{\pm}1.8yrs)$ participated in the study according to double-blind and cross-over protocols. Each volunteer was blindly administered 500mg of KG, KRG, FKRG extract or placebo (Dextrin). Blinded researchers measured changes of hyperventilation-induced cerebrovascular reactivity (CVR), mean blood flow velocity (MBFV) of middle cerebral arteries (MCAs) and corrected blood flow velocity at $P_{ETCO2}=40mmHg$ (CV40) using transcranial Doppler ultrasound (DWL Co., Germany). Researchers also observed changes of mean blood pressure (MBP), pulse rate (PR) and expiratory $CO_2$ using S/5 Collector (Datex-Ohmeda Co., Finland). The evaluation was performed at basal condition, and repeated at 1, 2, 3, 4 and 5 hours after administration. Results: MBFV and CV40 in the KRG group tended to rise at I hour after administration, while those of the FKRG group tended to rise at 2 hours after administration. CVR increased significantly after 1 hour in the KRG group (p=0.009) and after 2 hours in the FKRG group (p=0.035), respectively. The KG group showed increasing tendency at 4 hours after administration. No group showed significant difference from the placebo in changes of MBP and PR. Conclusions: It is suggested that KG, KRG and FKRG extracts have effects of enhancing CVR and thus of increasing cerebral blood flow in human subjects.

• Journal of Korea Foresty Energy
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• v.23 no.1
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• pp.45-68
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• 2004

The word of lignin is derived from the Latin word 'ligum' meaning wood. Lignin is complex polymer consisting of coniferyl alcohol, sinapyl alcohol and p-coumaryl alcohol unit and has an amorphous, three dimensional network structure which is hard to be hydrolyzed by acid. Lignin is found in the cell wall of plants lignified. The mode of polymerization of these alcohols in the cell wall lead to a heterogeneous branched and cross-linked polymer in which phenyl propane units are linked by carbon-carbon and carbon-oxygen bonds. This polymerization of precursors, p-coumaryl alcohol, coniferyl alcohol and sinapyl alcohol to lignin is formed by enzymic dehydrolyzation. The reaction is initiated by an electron transfer which results in the formation of resonance-stabilized phenoxy radical. The combination of these radicals produces a variety of dimers, trimers and oligomers and so on. Lignin research has been divided into basic and practical application field. The basic studies contains biosynthesis, chemical structure, distribution in the cell wall and reactivity by reductants, oxidants and organic solvents. The application research will be approached the reaction of lignin in various pulp making involving pulp bleaching and its effect on pulp qualities. Lignin also will be studied for the production of fine chemicals, polymer products and the conservation into an energy source like petroleum oil because the amount of lignin produced in pulp making process is more than 51,000,000 tons per year in the world. Both basic and application research must lay emphasis on the development for the utilization of lignin and the pulping process. But these researches can not be completed without understanding lignin structure containing functional groups. Therefore, this paper was focused on the review of lignin formulation which has been studied since 1948 in chronological order. This review was based on monomers, dimers, trimers and tetramers of phenyl propane unit structures which were isolated and identified by different methods from various wood.ious wood.

• Biomedical Science Letters
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• v.24 no.2
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• pp.138-142
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• 2018

The incidence of tuberculosis (TB) in the Republic of Korea remains high when compared to the incidence in other Organization for Economic Cooperation and Development (OECD) countries. The prompt diagnosis and effective treatment of latent TB infection (LTBI) are very important in terms of controlling the burden of TB. The tuberculin skin test (TST) has long been the "gold standard" assay for the diagnosis of LTBI. However, it can show false positive results due to Bacille Calmette-$Gu{\acute{e}}rin$ (BCG) vaccination and infection with many environmental nontuberculous mycobacteria (NTM). The interferon gamma release assay (IGRA) using Mycobacterium tuberculosis (MTB)-specific antigens, was developed for the detection of LTBI. The QuantiFERON-TB Gold In-Tube assay is one of the most commonly used forms of the IGRA. In order to compare the diagnostic efficacy of the TST and IGRA in relation to LTBI among BCG-vaccinated healthy donors, whole blood samples were collected from 51 participants, and the results of the TST and IGRA were compared. Of the 51 cases, 18 cases (35.3%) were positive and 33 cases (64.7%) were negative when using the TST, while four cases (7.8%) were positive and 47 cases (92.2%) negative when using the IGRA. There was no correlation between the size of the induration in the TST and the $IFN-{\gamma}$ protein level. In conclusion, the TST showed higher cross-reactivity among the BCG-vaccinated healthy participants, therefore, the IGRA might be the most suitable assay for the rapid screening of LTBI in BCG-vaccinated healthy population, or for TB contact investigation.

• Advances in concrete construction
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• v.6 no.4
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• pp.345-362
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• 2018

In this paper, mechanical and short-term durability properties of fly ash and slag based geopolymer concretes (FAGPC-SGPC) were investigated. The alkaline solution was prepared with a mixture of sodium silicate solution ($Na_2SiO_3$) and sodium hydroxide solution (NaOH) for geopolymer concretes. Ordinary Portland Cement (OPC) concrete was also produced for comparison. Main objective of the study was to examine the usability of geopolymer concretes instead of the ordinary Portland cement concrete for structural use. In addition to this, this study was aimed to make a contribution to standardization process of the geopolymer concretes in the construction industry. For this purpose; SGPC, FAGPC and OPC specimens were exposed to sulfuric acid ($H_2SO_4$), magnesium sulfate ($MgSO_4$) and sea water (NaCl) solutions with concentrations of 5%, 5% and 3.5%, respectively. Visual inspection and weight change of the specimens were evaluated in terms of durability aspects. For the mechanical aspects; compression, splitting tensile and flexural strength tests were conducted before and after the chemical attacks to investigate the residual mechanical strengths of geopolymer concretes under chemical attacks. Results indicated that SGPC (100% slag) is stronger and durable than the FAGPC due to more stable and strong cross-linked alumina-silicate polymer structure. In addition, FAGPC specimens (100% fly ash) showed better durability resistance than the OPC specimens. However, FAGPC specimens (100% fly ash) demonstrated lower mechanical performance as compared to OPC specimens due to low reactivity of fly ash particles, low amount of calcium and more porous structure. Among the chemical environments, sulfuric acid ($H_2SO_4$) was most dangerous environment for all concrete types.

• Parasites, Hosts and Diseases
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• v.51 no.4
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• pp.433-440
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• 2013

Toxocariasis is a worldwide zoonosis caused by larvae of ascarid nematodes of dogs or cats, Toxocara canis or T. cati. Diagnosis of human toxocariasis currently relies on serology that uses T. canis excretory-secretory antigen to detect specific IgG antibodies by ELISA. We investigated the serodiagnostic efficacy of ELISA using crude antigen of T. canis larvae (TCLA). Serum specimens of 64 clinically confirmed toxocariasis, 115 healthy controls, and 119 other tissue-invading helminthiases were screened by ELISA using TCLA. The ELISA using TCLA showed 92.2% (59/64 patient samples) sensitivity and 86.6% (103/119) specificity. Its positive diagnostic predictivity was 78.7% and negative predictivity was 97.8%. No serum of healthy controls reacted but that of anisakiasis (45.5%), gnathostomiasis (19.2%), clonorchiasis (15.8%), sparganosis (11.1%), and cysticercosis (6.3%) cross-reacted. Immunoblot analysis on TCLA recognized antigenic proteins of 28- and 30-kDa bands in their dominant protein quantity and strong blotting reactivity. The present results indicate that the ELISA using our TCLA antigen is acceptable by the sensitivity and specificity for serodiagnosis of human toxocariasis. ELISA with TCLA is recommended to make differential diagnosis for patients with any sign of organ infiltration and eosinophilia.

• Korean Journal of Microbiology
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• v.37 no.3
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• pp.221-227
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• 2001

Heat shock proteins serve as chaperone by preventing the aggregation of denatured proteins and promote survival of pathogens in harsh environments. In bacteria, ethanol shock induced the major chaperone GroEL and DnaK, but in Streptococcus pneumoniae, it induced neither GroEL nor DnaK but alcohol dehydrogenase (ADH). In this study, ADH gene encoding a 104-kDa (p104) protein was identified and characterized. The deduced amino acid sequence of pneumococcal ADH shows homology with other members of the ADH family, and particularly with Entamoeba histolytica ADH2 and E. coli ADH. S. pneumoniae adh is composed of 883 amino acids and its estimated isoelectric point is 6.09. Although ADH is conserved between S. pneumoniae and E. coli, immunoblot analysis employing antisera raised against pneumococcus ADH demonstrated no cross-reactivity with ADH analog in Eschericha coli, Staphylococcus aureus and human HeLa cells. Also secretion of ADH was demonstrated by subcellular fractionation and immunoblot analysis of proteins. These results suggest that S. pneumoniae ADH could be a highly feasible candidate for both diagnostic marker and vaccine.

• Korean Journal of Microbiology
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• v.43 no.1
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• pp.1-6
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• 2007

We describe a multiplex PCR method that can detect and differentiate simultaneously four different kinds of DNA viruses, Epstein-Barr virus (EBV), cytomegalovirus (CMV), hepatitis B virus (HBV) and parvovirus B19 (B19). Primers for the multiplex PCR reaction were designed to amplify specific regions of the EBV (pol), CMV (pol), HBV (pol) and B19 (ns) viral genomes and used to simultaneously detect individual viruses. In order to achieve optimal sensitivity and specificity for multiplex PCR, the thermo-cycling parameters, primer sequences, and concentration of each reaction components were optimized systematically. The sensitivity of the detection method ranged between 5 and 10 copies of viral genome with a mixture of multiple primer pairs. Furthermore, this highly sensitive test showed no cross-reactivity among the four viruses. Thus, the results obtained in this study provide evidence that the assay system is a good tool for supporting the diagnosis of viral infection and contamination.