• Restorative Dentistry and Endodontics
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• v.17 no.1
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• pp.191-205
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• 1992

The purpose of this study was to evaluate the microleakage of class II composite resin inlays and compare them with the conventional light-cured resin filling restorations. Class II cavities were prepared in 60 extracted human molars with which cervical margins were located below 1.0mm at the cemento-enamel junction using No. 701 tapered fissure carbide bur. All of the prepared cavities were restored as follows and divided into 6 groups. Group I and 2 were restored using direct filling technique and group 3,4,5 and 6 were restored using direct inlay technique that was cemented with dual-cured resin cements. group I: Cavities were restored with light-curing composite resin, Brilliant Lux. group 2. Cavities were restored with light-curing composite resin, Clearfil PhotoPosterior. group 3: Cavities were restored with Clearfil CR Inlay and heat treated at $125^{\circ}C$ for 7 minutes. group 4: Cavities were restored with same material as group 3 and heat treated at $100^{\circ}C$ for 15 minutes. group 5: Cavities were restored with Brilliant (Indirect esthetic system) and heat treated at $125^{\circ}C$ for 7 minutes. group 6: Cavities were restored with same material as group 5 and heat treated at $100^{\circ}C$ for 15 minutes. All specimens were polished with same method and thermocycled between $6^{\circ}C$ and $60^{\circ}C$, then immersed in a bath of 2.0% aqueous solution of basic fuchsin dye for 24 hours. Dyed specimens were sectioned longitudinally and dye penetration degree was read on a scale of 0 to 4 by Tani and Buonocore's method 45). The results were as follows: 1. Microleakage was observed rather at the cervical margins than at the occlusal margins in all groups. 2. Composite resin inlay groups showed significantly less leakage than direct filling groups at the cervical margins (p < 0.001). 3. In composite resin inlay groups, there was no significant difference in microleakage between specimens by heat treating temperature and time (p > 0.05). 4. There was no significant difference in leakage between each groups at the occlusal margins (p > 0.05).

• Journal of Soil and Groundwater Environment
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• v.19 no.2
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• pp.16-24
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• 2014

To test the potential effects of extracellular electron shuttles (EES) on the rate and extent of heavy metal release from contaminated soils during microbial iron reduction, we created anaerobic batch systems with anthraquinone-2,6-disulfonate (AQDS) as a surrogate of EES, and with contaminated soils as mixed iron (hydr)oxides and microbial sources. Two types of soils were tested: Zn-contaminated soil A and As/Pb-contaminated soil B. In soil A, the rate of iron reduction was fastest in the presence of AQDS and > 3500 mg/L of total Fe(II) was produced within 2 d. This suggests that indigenous microorganisms can utilize AQDS as EES to stimulate iron reduction. In the incubations with soil B, the rate and extent of iron reduction did not increase in the presence of AQDS likely because of the low pH (< 5.5). In addition, less than 2000 mg/L of total Fe(II) was produced in soil B within 52 d suggesting that iron reduction by subsurface microorganisms in soil B was not as effective as that in soil A. Relatively high amount of As (~500 mg/L) was released to the aqueous phase during microbial iron reduction in soil B. The release of As might be due to the reduction of As-associated iron (hydr)oxides and/or direct enzymatic reduction of As(V) to As(III) by As-reducing microorganisms. However, given that Pb in liquid phase was < 0.3 mg/L for the entire experiment, the microbial reduction As(V) to As(III) by As-reducing microorganisms has most likely occurred in this system. This study suggests that heavy metal release from contaminated soils can be strongly controlled by subsurface microorganisms, soil pH, presence of EES, and/or nature of heavy metals.

• Natural Product Sciences
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• v.22 no.2
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• pp.93-101
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• 2016

For efficient quality control of the Samryeongbaekchul-san decoction, a powerful and accurate an ultra-performance liquid chromatography (UPLC) coupled with electrospray ionization (ESI) tandem mass spectrometry (MS) method was developed for quantitative analysis of the thirteen constituents: allantoin (1), spinosin (2), liquiritin (3), ginsenoside Rg1 (4), liquiritigenin (5), platycodin D2 (6), platycodin D (7), ginsenoside Rb1 (8), glycyrrhizin (9), 6-gingerol (10), atractylenolide III (11), atractylenolide II (12), and atractylenolide I (13). Separation of the compounds 1 - 13 was performed on a UPLC BEH $C_{18}$ column ($2.1{\times}100mm$, $1.7{\mu}m$) at a column temperature of $40^{\circ}C$ with a gradient solvent system of 0.1% (v/v) formic acid aqueous-acetonitrile. The flow rate and injection volume were 0.3 mL/min and $2.0{\mu}L$. Calibration curves of all compounds were showed good linearity with values of the correlation coefficient ${\geq}0.9920$ within the test ranges. The values of limits of detection and quantification for all analytes were 0.04 - 4.53 ng/mL and 0.13 - 13.60 ng/mL. The result of an experiment, compounds 2, 6, 12, and 13 were not detected while compounds 1, 3 - 5, and 7 - 11 were detected with 1,570.42, 5,239.85, 299.35, 318.88, 562.27, 340.87, 12,253.69, 73.80, and $115.01{\mu}g/g$, respectively.

• Korean Journal of Pharmacognosy
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• v.42 no.3
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• pp.253-259
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• 2011

Macrophages play a vital role in the innate immune system involving defensive cytokines such as TNF (tumor necrosis factor)-${\alpha}$ and nitric oxide (NO). Therefore, we try to elucidate the anti-inflammatory activity of Chaga mushroom (Inonotus Obliquus, IO) in murine macrophages. Raw 264.7 cells and peritoneal macrophages of mice were cultured with or without LPS/LPS + IFN-${\gamma}$ in the presence of IO aqueous extracts (IOE 0.2, 2, 20, 100 ${\mu}g$/mL) for 24 hr and 48 hr, respectively. Exposure of IOE caused the decrease of NO production and increase of TNF-${\alpha}$ production in dose-dependent manner in activated peritoneal macrophage in vitro. To further investigate anti-inflammatory effects of IO ex vivo, we orally administrated capsaicin (PC, 3 mg/kg/day) and IOE (100, 200, 400 mg/kg/day) for 4 consecutive days to C57BL/6 mice (7~9 weeks old, female), then observed the NO secretion and cytokine (TNF-${\alpha}$) production of LPS/LPS + INF-${\gamma}$-stimulated peritoneal macrophages. IOE inhibits NO secretion in dose-dependent manner both ex vivo and in vitro and increases the production of TNF-${\alpha}$ in vitro. In addition, we found that IOE possessed suppressive effects of LPS-stimulated TNF-${\alpha}$, IL-$1{\beta}$, COX-2, as well as iNOS expressions in Raw 264.7 cells. These findings indicate that IOE suppress not only the LPS-induced NO overproduction of murine peritoneal macrophages, but also iNOS, COX-2, TNF-${\alpha}$, and IL-$1{\beta}$ overexpression of LPS-induced Raw 264.7 cells. Consequently, our results suggest that IO may have the anti-inflammatory effects via suppression of the inflammatory cytokines and mediators, and be useful for the treatment of inflammatory diseases.

• Proceedings of the Membrane Society of Korea Conference
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• 1998.10a
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• pp.15-18
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• 1998

Membrane reactors are systems which combine a chemical reactor with a membrane separation process allowing to carry out simultaneously conversion and product separation. The catalyst can be immobilized on the membrane or simply compartmentalized in a reaction space by the membrane. Membrane reactors are today investigated to produce optically pure isomers and/or resolve racemic mixture of enantiomers. The interest towards these systems is due to the increasing demand of enantiomerically pure compounds to be used in the pharmaceutical, food, and agrochemical industries. In fact, enantiomers can have different biological activities, which often influence the efficacy or toxicity of the compound. On the basis of current literature there are basically two schemes on the use of membrane technology to produce enantiomers. In one case, the membrane itseft is intrinsically enantioselective: the membrane is the chiral system which selectively separates the wanted isomer on the basis of its conformation. In the other, a kinetic resolution using an enantiospecific biocatalyst is combined with a membrane separation process; the membrane separates the product from the substrate on the basis of their relative chemical properties (i.e. solubility). This kind of configuration is widely used to carry out kinetic resolutions of low water soluble substrams in biphasic membrane reactors [Giomo, 1995, 1997; Lopez, 1997]. These are systems where enzyme-loaded membranes promote reactions between two separate phases thanks to the properties of enzymes, such as lipases, to catalyse reactions at the org ic/aqueous interface; the two phases are maintained in contact and separated at the membrane level by operating at appropriate transmembrane pressure. A schematic representation of biphasic membrane reactor is shown in figure 1, while an example of enantiospecific reaction and product separation carried out with these systems is reported in figure 2.

• Membrane Journal
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• v.13 no.2
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• pp.81-87
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• 2003

The permeation experiments f3r the aqueous dextran solutions of which the molecular weights were distributed between several thousands and million daltons were carried out using the dead-end cell system equipped with sheet membrane to determine the molecular weight cut-off (MWCO) of ultrafiltration membranes. The dextran rejections with respect to molecular weight were obtained by GPC analysis of feed and permeate solutions, then the MWCO was decided as the dextran molecular weight corresponding to the 90% rejection. The MWCO of PBTK membrane manufactured by Millipore was varied between 63,000 and 68,000 daltons as the pressure increased from 0.5 to 2.0 bar. However, the MWCO of PBQK(Millipore) and UE 1812(Saehan) under the above operating pressure increased to 3.5 and 4.3 times, respectively. Also, the MWCO of PBTK increased to 25% as the membrane permeation increased from 10 to 40% of the feed solution.

• Korean Journal of Materials Research
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• v.6 no.8
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• pp.768-778
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• 1996

Iron oxide (hematite, $\alpha$-${Fe}_{2}{O}_{3}$) particles were prepared directly from aqueous solution using a crystal growth controller. Paticles properties and reaction mechanisum of products as a function of basicity, formation process and mechanism of needle-lkie hematite were investigated. hexagonal hermatite particles were formed in teh range below pH 9.0, ellipsoidal or rectangular hematite particles in the range of pH 10.75-11.75 respectively. In the range above pH 12.50, acicular $\alpha$-FeOOH was formed. Basicity of product solution produced in the range of pH 10.7511.75 was increased slightly as compared with basicity of reastants due to hydroxly ion(OH-) formed by dissociation crystal growth controller. Citric acid which is acted as a crystal growth controller was adsorbed in the form of itrate anion(R-COO-) on the ferric hydroxide and exerted important role on the formation to the needle-like $\alpha$-${Fe}_{2}{O}_{3}$ particles in this reaction system.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.6
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• pp.1507-1515
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• 2006

Angelica gigantis (AG), Rehamaninae Radix(RR), Paenia japonica (PJ), and Polygoni multiflori Radix (PM) have been used as medicinal plants to tonify the blood. General function of the drugs have been known to nourish blood and control the heart and liver meridians. Recently, several studies have proposed mechanisms by which some oriental medicinal herbs work on the immune system. However, it is uncertain whether aqueous-extract of these drugs has immunomodulatory effect yet. In this study, I investigated the immune promotive effects of the water-extracted AG, RR, PJ and PM. The water-extracted AG, RR, PJ and PM inhibited NO production and iNOS expression in LPS stimulated RAW 264.7 macrophage cell line. Among these extracts, AG and PM induced expression of IL-2 and IFN${\gamma}$ in mouse spleen cells. In the flow cytometry analysis, PM-stimulated mouse spleen cells showed an increase in B-cell phenotype (CD45R/B220). The oral administration of Polygoni multiflori water-extracts to mice having S-180 abdominal dropsy cancer prolonged life-span more than control mice. These data suggest that among these extracts, PM has cellular and humoral immune-enhancement effect through IL-2 and IFN${\gamma}$ cytokine production, the regulation of NO production in macrophage cells and the B cell production in spleen cells.

• Preventive Nutrition and Food Science
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• v.3 no.2
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• pp.143-151
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• 1998

Protein -surfactant interactions have been investigate by measuring ζ-potential of $\beta$-lactoglobulin-coated emulsion droplets and $\beta$-lactoglobulin in solution in the rpesenceof surfactant, with particular emphasis on the effect of protein heat treatment(7$0^{\circ}C$, 30min). When ionic surfactant (SDS or DATEM) is added to the protein solution, the ζ-potential of the mixture is found to increase with increasing surfactant concentration, indicating surfactant binding to the protein molecules. For heat-denatured protein,it has been observed that the ζ-potential tends to be lower than that of the native protein. The effect of surfactant on emulsions is rather complicated .With SDS, small amounts of surfactant addition induce a sharp increase in zeta potential arising from the specific interaction of surfactant with protein. With further surfacant addition, there is a gradual reductio in the ζ-potential, presumably caused by the displacement of adsorped protein (and protein-surfactant complex) from the emulsion droplet surfac by the excess of SDS molecules. At even higher surfactant concentrations, the measured zeta potential appears to increase slightly, possibly due to the formation of a surfactant measured zeta potential appears to increase slightly, possibly due to the formation of surfactant micellar structure at the oil droplet surface. This behaviour contrastswith the results of the corresponding systems containing the anionic emulsifier DATEM, in which the ζ-potential of the system is found to increase continuously with R, particularly at very low surfactant concentration. Overall, such behaviour is consisten with a combination of complexation and competitive displacement between surfactant and protein occurring at the oil-water interface. In addition, it has also been found that above the CMC, there is a time-dependent increase in the negative ζ-potential of emulsion droplets in solutions of SDS, possibly due to the solublization of oil droplets into surfactant micelles in the aqueous bulk phase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.4
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• pp.606-613
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• 1997

The changes of contents in trimethylamine oxide nitrogen(TMAO-N), trimethylamine nitrogen(TMA-N), dimethylamine nitrogen(DMA-N), nitrite nitrogen(nitrite-N), nitrate nitrogen(nitrate-N) and the effect on the formation of N-nitrosamine(NA) during fermentation were investigated with salted anchovy added different amounts of sodium nitrite, sodium nitrate and ascorbic acid, respectively. When the sodium nitrite was added in salted anchovy, the contents of nitrite-N was decreased during fermentation . Whereas the formation of N-nitrosodimethylamine(NDMA ) was increased . Contents of TMAO-N was decreased, while TMA-N and DMA-N were increased during fermentation in all samples. Addition of ascorbic acid inhibited the formation of NDMA significantly. The formation of NDMA was inhibited by 81.3% at the concentration of 130mM as compared with non-added the control group. The aqueous model system was used for the evaluation of ascorbic acid(inhibitor) or thiocyanate (promoter) on the formation of NDMA using salt-fermented anchovy added with sodium nitrite. The optimum pH on the formation of NDMA was shown to be 3.8, and ascorbic acid inhibited the formation of NDMA whereas thiocyanate promoted. NDMA was not detected in the salt-fermented anchovy (control sample). However it is a possibility to form carcinogenic NDMA in stomach if both saltfer-mented anchovy and the materials contained abundant nitrite or nitrate were took in.