• Biomedical Science Letters
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• v.12 no.4
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• pp.443-450
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• 2006

To demonstrate their possibilities as an enhanced vaccine delivery system, protein-loaded Poly lactide glycolide copolymer (PLGA) microspheres were prepared with different physical characteristics. Ethyl acetate (EA) solvent extraction process was employed to prepare microspheres and the effects of process parameters on drug release properties were evaluated. The biodeuadability of microspheres was also evaluated by the pH change and GPC (Gel permeation chromatography). Primary IgG antibody responses in BALB/c mice were compared with protein saline solutions as negative controls and adsorbed alum suspensions as positive controls after single subcutaneous injection for in vivo studies. The microspheres showed a erosion with a highly porous structure and did not keep their spherical shape at 45 days and this result could be confirmed by GPC. In vitro release of proteinous drug showed initial burst effect in all batches of microspheres, followed by gradual release over the next 4 weeks. PLGA microspheres were degraded until 45 days and the secondary structure of OVA was not affected by the preparation method. Enzyme-linked immunosorbent assays demonstrated that the single subcutaneous administrations of OVA-loaded PLGA microspheres induced enhanced serum IgG antibody response in comparison to negative and positive controls. These results demonstrated that microspheres providing the controlled release of antigens might be useful in advanced vaccine formulations for the parenteral carrier system.

• Advances in Traditional Medicine
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• v.1 no.1
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• pp.37-44
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• 2000

In the previous paper (Kim et al., Glycoconjugate Journal 16, 247-252, 1999), heteropolysaccharides from Korean medicinal plant, Phellodendri cortex (Hwangbek) showed a poten B-Iymphocyte-stimulating activity in a system using polyclonal antibody forming cells in C57BL/6XC3H mice at dosages of 2-10 mg. In a series of biolgical active polysaccharides from natural medicinal plants, the polysaccharide fractions were isolated and purified from Phellodendron chinese SCHNEID, and antitumor activities were examined at dosages of 2, 5 and 10 mg/100 g. F-7 and F-8 showed the highest tumor inhibitory activities (inhibition ratio 96.4 and 98.2% in 2 mg/100 g), and in dose of 5 mg/100 g, the inhibitory ratios were 95.3 and 97.5%, respectively. Furthermore, 10 mg/100 g of intraperitoneal (i.p.) injection gave 97.3 and 98.7% of inhibition. In oral administration, the inhibitory activities were not markedly observed, indicating that the polysaccharides are directly acting to immune system. When the effects on TS and TK activities were determined, TS activities in the F-2 and F-7-treated mice were markedly suppressed to 73.7% and 79.5% of that in the control (p<0.01), while there was little difference in TK activity with a slight decrease in F-2 only. However, in i.p. injection, TS activities in the F-2, F-5, F-7 and F-8-treated mice were markedly suppressed to 83% to 85% of that in the control (p<0.01). Furthermore, there was also significant differences in TK activities in F-2, F-5, F-7 and F-8-treated mice (p<0.05). Therefore, polysaccharide fraction F-8 was further purified to active fractions of F-9 and F-11 by gel permeation chromatography using TSK Gel HW50S. The purified polysaccharides of F-9 and F-11 were composed of GlcNAc (47.3%), Gal (24.7%) and Man (28.0%). These results clearly indicated that the i.p. injection is much effective to suppress tumor growth than oral administration.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.41 no.7
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• pp.463-468
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• 2017

For transdermal drug delivery, needless injection system is composed of laser and microjet injector. Main mechanism of microjet injector is the laser-induced bubble. Nd:YAG and Er:YAG laser are used as a power source. Laser parameters such as pulse duration and wavelength are considered, which are core parameters to control the bubble motion. The Nd:YAG laser, pulse duration is short than bubble life time making cavitation like bubble while in Er:YAG laser, long pulse duration and high absorption in water drive bubble as a boiling bubble. Detailed motion of bubble and microjet is captured by the high speed camera. So it is observed that microjet characteristics are determined by the bubble behavior. The performance of drug delivery system is evaluated by fluorescent staining of guinea pig skin.

• Journal of Korean Physical Therapy Science
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• v.7 no.2
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• pp.597-605
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• 2000

There has been several usual ways to cure pain in osteological muscle: use oral medicine or injection, or apply medicine to a sore place. The purpose of this study was to examine, by using thermometer and digital infrared thermographic imaging, how much the permeation of aceclofenac, an anodyne and antiphlogistic, into sore skin brought a change to skin temperature after that was' applied to it. The findings of this study were as below; 1. A cream made of aceclofenac yielded $0.61^{\circ}C$ difference in temperature, but the difference wasn't statistically significant. 2. An aceclofenac to which oleic acid was added went through microemulsion and applied, and there was $0.3^{\circ}C$ change in temperature, the biggest significant difference(P<.05), after approximately 15 minutes passed. 3. An aceclofenac to which labrasol was added went through microemulsion and applied, and there was a growing rise in temperature with the lapse of time. After 30 minutes passed, the final temperature showed $1.25^{\circ}C$ rise, which was a significant change(P<.05). 4. As the temperature was measured by digital infrared thermographic imaging, there was about $3.97^{\circ}C$ fall, the biggest change, which was significant(P<.05). The findings of this study suggested that the application of aceclofenac to sore skin caused a change in skin temperature, as that permeated into it.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.179-190
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• 2003

The grout based on solution type makes it difficult to get the improvement of ground strength and the effefct of water curtain because it has lower strength and durability than suspension type. Nowadays, the technology of particle acceleration, that enhance the material permeability, such as grout based on solution type, and inexpensive grout, is being required. For these reasons, in this study, using wet milling system, we evaluated physical properties of manufactured factors such as water-cement ratio of particles before being milled, optimum milling capacity by controlling milling time and rpm, viscosity of materials, permeation coefficient, and unconfined compressive strength. Also, using micro wet milling apparatus which could manufacture ordinary Portland cement and high speed shear mix which could forcefully separate conglomerate particles in situ, we performed electrical resistivity investigation and falling head permeability tests to analyze differences of grouting effects. From these results, we found that the permeability of the applied equipment was much superior, and in the case of using high speed shear mixer, particles of grout material were well separated.

• YAKHAK HOEJI
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• v.49 no.2
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• pp.140-146
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• 2005

Candida albicans, a polymorphic fungus, causes systemic and local infections. Recent reports show that the fungus is a main etiological agent for the arthritis. For trea tment, antifungal drugs and/or rheumatoid drugs are used, but resistance and side effects limit application of the drugs. In search of new sources for treatment of the fungal arthritis, we choose Egb 761 (extract of Ginkgo leaves 761), one of the most popular over-the-counter herbal medicines. The Egb 761 contains two major ingredients such as terpene and flavonoid. In the present study, we examined if the terpene portion of Egb 761 had anti-inflammatory activity against C.albicans-caused arthritis. The terpene was extracted with combination of methanol and water from the Egb 761, followed by gel-permeation chromatography. Presence of terpene was determined by the Salkowski colorimetric method and HPLC analysis. For an animal model of inflammation induction, mice were given an emulsion form of C.albicans cell wall mixed with Complete Freund's Adjuvant (CFA) by footpad-injection. Results showed that intraperitoneal administration of the water-soluble portion that contained terpene and flavonoid reduced the inflammation. Whereas the terpene had anti-inflammatory activity, flavonoid portion had no such activity, For determination of possible mechanism of the activity, the terpene seemed to be suppression of nitric oxide (NO) production from LPS-treated macrophages. Taken together the Ginkgo terpene may have anti-inflammatory effect against C.albicans-caused arthritis, possibly by blocking NO production.

• Journal of Surface Science and Engineering
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• v.51 no.5
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• pp.277-290
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• 2018

In this study, Pd-Ni-Ag alloy hydrogen separation membranes were fabricated by Pd/Ag/Pd/Ni/Pd multi-layer sputter deposition on the modified MIM(Metal Injection Molding)-PSS(Porous Stainless Steel) support and followed heat treatment. Nickel, used as an alloying element in Pd alloy membranes, is inexpensive and stable material in a hydrogen isotope environment at high temperature up to 1123 K. Hydrogen perm-selectivity of Pd-Ni-Ag alloy membranes is affected not only by composition of membrane films but also by other factors such as surface properties of PSS support, microstructure of membrane films and inter-diffused impurities from PSS support. In order to clarify the effect of surface Ni composition on hydrogen perm-selectivity of Pd-Ni-Ag alloy membranes, the other effects were significantly minimized by the formation of dense and homogeneous Pd-Ni-Ag alloy membranes. Hydrogen permeation test showed that hydrogen permeability decreased from $7.6{\times}10^{-09}$ to $1.02{\times}10^{-09}mol/m{\cdot}s{\cdot}Pa^{0.5}$ as Ni composition increased from 0 to 16 wt% and the selectivity for $H_2/N_2$ was infinite.

• Journal of Pharmaceutical Investigation
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• v.39 no.6
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• pp.393-400
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• 2009

PHEA (hydroxyethyl-aspartamide)-mPEG (methoy-polyethyleneglycol)-$C_{16}$ (hexadecylamine)-ED (ethylenediamine) was prepared as a drug delivery carrier. The structure and molecular weight of polymers were characterized by $^1H$-NMR and gel permeation chromatography. Micelle size and shape were measured by electro-photometer light scattering and transmission electron microscope. The mean diameter of micelles was 23 nm in aqueous solution. To evaluate the potential of these polymeric micelles as a drug carrier, PSI-mPEG-$C_{16}$-ED was conjugated with Cy5.5 for Near-Infrared Fluorescent (NIRF) based optical imaging. PSI-mPEG-$C_{16}$-ED-Cy5.5 was injected intravenously into mice (n=5) and in vivo NIRF imaging was performed during 48 h after injection. The biodistribution study at 24 h after injection showed the longcirculation property of PSI-mPEG-$C_{16}$-ED-Cy5.5. Therefore, PSI-mPEG-$C_{16}$-ED micelles could be a promising drug carrier and imaging agent.

• Journal of Embryo Transfer
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• v.29 no.3
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• pp.235-240
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• 2014

Ethylene glycol (EG) has been successfully used as a cryoprotectant for vitrification of mammalian embryos (including human embryos) due to its low formula weight and high permeation into cells compared with other cryoprotectants, including propylene glycol (PROH). Cryopreservation is able to store the surplus pre-embryos for freezing and furthermore thawing and transfer in a subsequent cycle. This study was carried out to evaluate the effects of embryonic stage, cryoprotectant, and freezing-thawing method on the rates of survival and development of the cryopreserved mouse early embryo and finally to establish the cryopreservation method of surplus embryos obtained during assisted reproductive technology (ART). Female ICR mice (6~8 weeks old) were induced to superovulate by sequential intraperitoneal injection of 5 IU PMSG and 5 IU hCG 48 h apart. Mouse embryos were collected according to its developmental stage after the injection of hCG. Embryos were cryopreserved not only during cryoprotectant step (1~4 step) but also in a variety of media (HTF, IVF medium, D-PBS) and cell stage. The results were as follows : There is no clear advantage in these freezing media of rapid method, but 4 cell and 8 cell of slow method (2, 3 and 4 step) have advantage in D-PBS. The development of embryos according to cell stage become greater in 8 cell stage. In the treatment steps of cryopreservation, the development of embryo to blastocyst was similar among rapid method, but the development of 4 cell and 8 cell embryos to blastocyst according to slow method was better than rapid method.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.223-229
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• 2010

In this study diverse dehydrogenative polymers (DHPs) were synthesized with three precursors of native lignin [p-coumaryl alcohol (PCA), coniferyl alcohol (CA), sinapyl alcohol (SA)] in the presence of horseradish peroxidase (HRP, EC. 1.11.1.7)/$H_2O_2$. To compare the structural features between DHPs and native lignin, the DHPs as well as pine/poplar milled wood lignins were simultaneously subjected to gel permeation chromatography (GPC) to determine average molecular weights and derivatization followed by reductive cleavage (DFRC) to investigate the frequency of ${\beta}$-O-4 linkage. The highest yield of DHP was measured to 71% when CA was solely injected (G-DHP) and the yield of H-DHP was 42%. However, single injection of SA could not form any polymer in this system. The average molecular weights of DHPs were ranged between 3,000~4,700, which were only 1/2 fold compared with that of pine MWL (G-type lignin: Mw 7,340) and 1/3 scale compared with that of poplar MWL (GS-type lignin: Mw 13,250). DFRC analysis revealed that the formation of ${\beta}$-O-4 linkage during dehydrogenative polymerization was the highest in the GS-DHP with ca. 502 ${\mu}mol$/g, which was, however, remained to only 50% compared to that in poplar MWL (1107 ${\mu}mol$/g). The ${\beta}$-O-4 linkage was estimated to ca. 286 ${\mu}mol$/g In the G-DHP, which was twice as much as that of H-DHP(127 ${\mu}mol$/g). Similar to GS-DHP, only half amount of ${\beta}$-O-4 linkage, compared to pine MWL, was formed during in vitro polymerization of CA by horseradish peroxidase/$H_2O_2$.