• Journal of Korean Society of Forest Science
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• v.95 no.4
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• pp.429-434
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• 2006

The dried needles (1.5 kg) of Picea abies Karsten were ground, extracted with acetone-$H_2O$ (7:3, v/v), concentrated, and fractionated with a series of n-hexane, methylene chloride, ethyl acetate and water on a separatory funnel. Each fraction was freeze dried, then a portion of ethyl acetate soluble powder was chromatographed on a Sephadex LH-20 column using a series of aqueous methanol and ethanol-n-hexane mixture as eluents. The isolated compounds were identified by cellulose TLC, $^1H$-, $^{13}C$-NMR, FAB and EI-MS. (+)-catechin (compound I), (-)-epicatechin (compound II), kaempferol-3-O-${\beta}$-D-glucopyranoside (compound III), 4-hydroxyacetophenone (compound IV) were isolated from the ethyl acetate soluble fraction and (+)-catechin (compound I), protocatechuic acid (compound V) were isolated from the $H_2O$ soluble fraction of P. abies needle. The antioxidative activities of each fraction and the isolated compounds were tested by DPPH radical scavenging method, and EtOAc soluble fraction, (+)-catechin and (-)-epicatechin showed similar values to ${\alpha}$-tocopherol and BHT as controls.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.24 no.4
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• pp.405-415
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• 2014

Objectives: The aim of this study is to comprehensively summarize endotoxin levels reported in operations using metalworking fluids(MWFs). Methods: An extensive literature review was conducted of studies reporting endotoxin levels in processes using metalworking fluids. Keyword search terms included 'metalworking fluids', 'machining fluids', 'metalworking operation', 'machining operation' and 'endotoxin', which were used in combination. Results: A total of ten manuscripts were found to report on airborne endotoxin levels from metalworking operations in the automobile industry. Polycarbonate(PC), polyvinyl chloride(PVC) and mixed cellulose ester(MCE) were used to collect airborne endotoxin. Limulus Amebocyte Lysate was mainly used to quantify endotoxin amount. The levels of airborne endotoxin reviewed varied considerably, ranging from < $4EU/m^3$ to $790EU/m^3$, which was found to be far lower than those from cotton and potato processing plants, sawmills, and poultry farms. Several studies assumed that exposure to endotoxin could be a causative agent of respiratory diseases. Conclusions: Inhalation endotoxin exposure levels reported from metalworking operations were found to be lower than those from industries handling organic materials, even though it could be considered as a possible cause for several respiratory diseases.

• KSBB Journal
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• v.26 no.3
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• pp.217-222
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• 2011

Itraconazole is a triazole antifungal agent to inhibit most fungal pathogens. To improve the oral absorption and dissolution of poorly water-soluble itraconazole, microsponge system composed of $Eudragit^{(R)}$ E100 and polyvinyl alcohol(PVA) formulated by quasi-emulsion solvent diffusion method, and its physicochemical properties and pharmacokinetic parameters of itraconazole were studied. The microsponge of itraconazole were discrete free flowing micro sized particles with perforated orange peel like morphology as visualized by scanning electron microscope (SEM). Results showed that the drug loading efficiency, production yield, and particle size of itraconazole microsponge were affected by drug to polymer ratio, the volume of internal phase containing methylene chloride, stirring rate and the concentration of PVA used. Also, the results showed that the dissolution rate of itraconazole from the microsponges was affected by drug to polymer ratio. In other words, the release rate of itraconazole from microsponges was increased from at least 27.43% to 64.72% after 2 h. The kinetics of dissolution mechanism showed that the dissolution data followed Korsmeyer-Peppas model. Therefore, these results suggest that microsponge system can be useful for the oral delivery of itraconazole by manipulating the release profile.

• Journal of Sericultural and Entomological Science
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• v.43 no.1
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• pp.41-48
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• 2001

The purification, dissolution and powdering of stained waste silk obtained from weaving and dyeing process were studied for the surface modification of textile fabric and plastic materials. The whiteness of stained waste silk could be improved through degumming and bleaching with sodium hydrosulfite. The water-soluble fibroin solution can be obtained by dissoving the degummed waste silk in a boiling solution of 50% calcium chloride for 60 minutes. The salts and heavy metals contained in fibroin solution were removed by electric dialysis, wool fiber filtration and gel filtration chromatography. The fibroin powder was prepared by using a fine grinder after the alkali treatment for weakening the silk fiber. The fine fibroin powder of particle size around 30 ㎛ was obtained with a ultra fine-mill, while it was finer below 10 ㎛ with a ball-mill. The dissolved or powdered silk was applied to the surface of fabric with addition of the binder (a urethane resin). The moisture content of polyester and nylon fabrics treated with the silk solution was improved due to hygroscopic property of silk. The fine fibroin powder mixed with the binder ws coated on the surface of synthetic film by use of the air pressed sprayer. It was revealed that the hygroscopicity as well as the softness of fibroin powder coated film was much improved. Therefore, it is thought that the fine silk fibroin powder is applicable as an coating agent for the surface modification of plastic and synthetic leather.

• Bulletin of the Korean Chemical Society
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• v.25 no.5
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• pp.715-720
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• 2004

Amineterminated, ethylenediamine core polyamidoamine starburst dendrimers of generation 2 (G2), generation 4 (G4) and generation 6 (G6) have been successfully surface-modified via an amide coupling reaction with 4-ethyl, 4'-(3-propionic) bipyridinium cation and the electrochemical behavior of the resulting dendrimers were investigated in aqueous potassium chloride electrolyte solutions. The 1-[3-(dimethylamino)propyl]-3-ethylcarbodiimide hydrochloride/N-hydroxysuccinimide-mediated reaction resulted in 25-39% end-group functionalization. The water-soluble 4-ethyl, 4'-(3-propylamide) bipyridinium dibromide dendrimers (G2-V2+, G4-V2+ and G6-V2+) were characterized by $^1H$ NMR and UV-Vis spectroscopic methods. The cyclic voltammetric and chronoamperometric experiments were performed to determine the diffusion coefficient and the number of electrons transferred in the process of the first reduction of the viologen-functionalized dendrimers. Adsorption of viologen-functionalized dendrimers at electrode surface was evidenced in the voltammograms. Experimentally determined diffusion coefficients were in good agreement with the values expected from the Stokes-Einstein relation, while the number of electrons transferred concurred with the extent of functionalization determined by $^1H$ NMR and UV-Vis spectra.

• Korean Journal of Pharmacognosy
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• v.16 no.2
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• pp.73-80
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• 1985

Experimental studies were undertaken to investigate for the effect of Yijin-tang on the digestive system and isolated uterus of rats. Yijin-tang was composed of five crude drugs; Pinelliae Tuber, Aurantii nobilis Pericarpium, Hoelen, Glycyrrhizae Radix and Zingiberis Rhizoma. The results obtained from experiments with water soluble fraction extracted from Yijin-tang were as follows; Spontaneous motilities of isolated ileum of mice and rabbits were suppressed, and contraction of isolated ileum of mice and guinea-pigs induced acetylcholine, barium chloride and histamine were inhibited. The anticathartic action of mice induced by castor oil were significantly observed. The spontaneous motility of isolated uterus of rats was suppressed. Inhibitory effect of gastric juice secretion and antiulcerogenic action were significantly shown in Shay rats.

• Preventive Nutrition and Food Science
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• v.16 no.3
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• pp.217-223
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• 2011

Ischemic stroke constitutes about 80% of all stroke incidences. It is characterized by brain cell death in a region where cerebral arteries supplying blood are occluded. Under these ischemic conditions, apoptosis is responsible for the cell death, at least in part. Goat's-beard (Aruncus dioicus var. kamtschaticus) is a perennial plant that grows naturally in the alpine regions of Korea. In the present study, we first determined whether water extract of goat's-beard (HY1646) and some of its fractions prepared by partitioning with organic solvents could improve the viability of human hepatocellular carcinoma cells (HepG2) cultured under hypoxic condition by blocking apoptotic pathways. Based on the in vitro findings, we subsequently investigated whether HY1646 and the ethyl acetate fraction (EA) selected from cell culture-based screening could attenuate brain injury in a rat middle cerebral artery occlusion (MCAO) model of ischemia (2 hr), followed by 22 hours of reperfusion. The cell number was sustained close to that initially plated in the presence of HY1646 even after 24 hr of cell culture under hypoxic condition (3% $O_2$), at which time the cell number reached almost zero in the absence of HY1646. This improvement in cell viability was attributed to the delay in apoptosis, identified by the formation of DNA ladder in gel electrophoresis. Of fractions soluble in hexane, ethyl acetate (EA) and butanol, EA was chosen for the animal experiments because EA demonstrated the best cell viability at the lowest concentration (10 ${\mu}g$/mL). HY1646 (200 mg/kg) and EA (10 and 20 mg/kg) significantly reduced infarct size, an index of brain injury, by 16.6, 40.0 and 61.0%, respectively, as assessed by 2,3,5-triphenyl tetrazolium chloride staining. The findings suggest that prophylactic intake of goat's beard might be beneficial for preventing ischemic stroke.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.379-386
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• 1996

Photosensitive compound, 1-methyl-4-[2-(4-diethylacetylphenyl)ethenyl] pridinium methosulfate(SbQ-A salt), was synthesized from dimethyl sulfate, terephthalaldehyde mono-(diethylacetal) and 4-picoline. SbQ-A salts were reacted with poly(vinyl alcohol)s, (PVA) in aqueous solution with phosphoric acid as catalyst to give photosensitive PVA-SbQ with different SbQ content and molecular weight. Relative photosensitivity of PVA-SbQ was determined by gray scale(GS) method. The rotative sensitivity of PVA-SbQ increased with increasing amount of bound SbQ in the case of high molecular weight(MW=77,000-79,000g/mol) as substrate and decreased with decreasing molecular weight of PVA with about constant(1.3mol%) amount of bound SbQ. The most sensitive polymer was obtained when SbQ group content in PVA-SbQ reached about 2.63mol% in the case of high molecular weight(77,000-79,000g/mol) PVA. This sample showed 90 times greater sensitivity than dichromated PVA as reference photosensitive system. PVA-SbQ photosensitive polymer synthesized was applied to the photolithographic screening process of phosphor on the panel of cathode ray tube(CRT). Phosphor slurry was made with PVA-SbQ, phosphor, a small amount of surfactant and other additives using water as medium. The slurry was coated onto panel, dried by heater, exposed to UV light and then developed by distilled water. When a small amount of cationic surfactant such as cetyltrimethylammonium chloride was used in the slurry formulation, the sharpness of phosphor pattern was equal to or better than that of dichromated PVA photosensitive polymer system used currently.

• Clinical and Experimental Pediatrics
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• v.46 no.2
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• pp.198-202
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• 2003

Of all toxic inhalant exposures, chlorine is one of the most common toxic chemical inhalants. When acutely inhaled, it can be responsible for symptoms ranging from upper air way irritation to more serious respiratory effects. It can also deteriorate lung function and lead to death. Chlorine and its compounds such as chlorinated cyanurates and hypochlorites are commonly used in water disinfection. The chemical agents discussed in this article are sodium dichloroiso cyanurate and calcium hypochlorite which are the two most popular products for swimming pool chlorination. They are both strong oxidizing agents which are soluble in water. Between the above two alkali agents, acid-base interaction occurred and generated heat. And the acid drove the combination of hypochlorous and chloride ions to form chlorine gas. We have experienced, two boys who had inhalation injuries caused by an accidental explosion which occurred in a swimming pool by mixing two different chlorinating agents : sodium dichloroiso cyanurate and calcium hypochlorite. The children suffered from respiratory difficulties after the exposure. They both required intensive care management and one needed the support of mechanical ventilation.

• Journal of Forest and Environmental Science
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• v.21 no.1
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• pp.24-33
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• 2005

Fallen needles (8.5kg) of Larix kaempferi were separately collected, extracted with 95% EtOH. EtOH extract was evaporated under reduced pressure, concentrated then successively fractionated with a series of hexane, methylene chloride, ethylacetate and water on a separatory funnel. Then, each fraction was freeze dried. A portion of ethylacetate and water soluble powder were packed on a column chromatography (Sephadex LH-20) eluting with aqueous MeOH and EtOH-hexane mixture. Spectrometric analyses such as NMR and FAB-MS including TLC were performed to characterize the structures of isolated compounds. 5 compounds were isolated from the fallen needles of Larix kaempferi. The antioxidative activities of each fraction and isolated compounds were done by DPPH radical scavenging test.