• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05b
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• pp.173-176
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• 2004

The piezoelectric ceramics for AE sensor piezoelectric devices are desirable to possess higher resonance vibrations. The compositions of $0.9Pb(Zr_xTi_{1-x})O_3-0.1Pb(Mn_{1/3}Nb_{1/3}Sb_{1/3})O_3$ (PZT-PMNS) in this work are selected for obtaining especially large electromechanical coupling factor, high mechanical quality factor and high Curie temperature. This ceramic has higher piezoelectric activity and higher electromechanical coupling factor, but the ceramic has lower Curie temperature. The piezoelectric and dielectric characteristics of PZT-PMNS ternary system are investigated as functions of $Ti^{2+}$, $Zi^{2+}$ mol rate. As the results, MPB(morphotropic phase boundary) in this piezoelectric ceramic is x=0.522. Resonance vibrations of PZT ceramics are investigated as ball-bearing drop test. For the use of AE sensor that driving with pre-amplifier, filter circuit after packed this ceramic and an elastic body.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07a
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• pp.515-518
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• 2004

The Piezoelectric ceramics for AE(Acoustic Emission) sensor are desired large electromechanical coupling factor, high mechanical quality factor and good characteristic resonance frequency. In this study, the empirical formula of specimens is used $0.9Pb(Zr_xTi_{1-x})O_3-0.1Pb(Mn_{1/3}Nb_{1/3}Sb_{1/3})O_3$ (PZT-PMNS). The piezoelectric and dielectric characteristic are investigated by sintering temperature and value of x as functions of $Ti^{2+},\;Zi^{2+}$ mol rate. MPB(morphotropic Phase boundary) is defined in the x=0.522. Because it is appeared to the best piezoelectric and dielectric characteristic in the x=0.522, it can be application by AE sensor. PZT-PMNS ceramics without pre-amplifier and filter are tested for detecting of arc signal. The detection characteristic is evaluated wave form, frequency distribution.

• KIEE International Transactions on Electrophysics and Applications
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• v.5C no.3
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• pp.102-110
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• 2005

Piezoelectric transformers(PT) are expected to be small, thin and highly efficient, and which are attractive as a transformer with high power density for step down voltage. For these reasons, we have attempted to develop a step-down PT for the miniaturized adaptor. We propose a PT, operating in thickness extensional vibration mode for step-down voltage. This PT consists of a multi-layered construction in the thickness direction. In order to develop the step-down PT of 10 W class and turn ratio of 0.1 with high efficiency and miniaturization, the piezoelectric ceramics and PT designs are estimated with a variety of characteristics. The basic composition of piezoelectric ceramics consists of ternary yPb(Zr$_{x}$Ti$_{1-x}$)O$_{3}$-(1-y)Pb(Mn$_{1/3}$Nb1$_{1/3}$Sb$_{1/3}$)O$_{3}$. In the piezoelectric characteristics evaluations, at y=0.95 and x=0.505, the electromechanical coupling factor(K$_{p}$) is 58$\%$, piezoelectric strain constant(d$_{33}$) is 270 pC/N, mechanical quality factor(Qr$_{m}$) is 1520, permittivity($\varepsilon$/ 0) is 1500, and Curie temperature is 350 $^{\circ}C$. At y = 0.90 and x = 0.500, kp is 56$\%$, d33 is 250 pC/N, Q$_{m}$ is 1820, $\varepsilon$$_{33}$$^{T}$/$\varepsilon$$_{0}$ is 1120, and Curie temperature is 290 $^{\circ}C$. It shows the excellent properties at morphotropic phase boundary regions. PZT-PMNS ceramic may be available for high power piezoelectric devices such as PTs. The design of step-down PTs for adaptor proposes a multi-layer structure to overcome some structural defects of conventional PTs. In order to design PTs and analyze their performances, the finite element analysis and equivalent circuit analysis method are applied. The maximum peak of gain G as a first mode for thickness extensional vibration occurs near 0.85 MHz at load resistance of 10 .The peak of second mode at 1.7 MHz is 0.12 and the efficiency is 92$\%$.

• 대한상한금궤의학회지
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• v.13 no.1
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• pp.21-44
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• 2021

Objective : This study aimed to assess the preventive effect of Bupleuri Radix aqueous extracts (BR) and red koji-fermented BR (fBR) in lipopolysaccharide (LPS)-induced acute lung injury in a rat model. Methods : Rats were administered 30, 60, or 120 mg/kg/day of fBR for 28 days before LPS treatments. All rats were sacrificed 5 h after LPS treatment (500 ㎍/head, intratracheal instillation). Body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters (pH, partial pressure [Pa] of O2, PaCO2), bronchoalveolar lavage fluid (BALF) protein, lactate dehydrogenase (LDH), tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), total cell numbers, neutrophil/alveolar macrophage ratios, lung malondialdehyde (MDA), and myeloperoxidase (MPO) were measured. In addition, histopathological changes including the luminal surface of alveoli (LSA), thickness of alveolar septum, and number of polymorphonuclear neutrophils (PMNs) were checked. Results : LPS injection led to increases in lung weights, pulmonary transcapillary albumin transit, BALF protein, LDH, TNF-α and IL-1β contents, total cells, neutrophil and alveolar macrophage ratios, lung MDA, MPO, alveolar septum thickness, and PMNs, and decreases in PaCO2 and pH of arterial blood and LSA. However, these LPS-induced acute lung injuries were inhibited by pretreatment of 30, 60, and 120 mg/kg of fBR. The most favorable effects were seen with 30 mg/kg fBR as compared with 60 mg/kg of α-lipoic acid and BR. Conclusions : fBR showed preventive effects on LPS-induced acute lung injury, which resembles acute respiratory distress syndrome. The mechanisms of action were likely via antioxidant and anti-inflammatory means.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2001.11a
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• pp.14-20
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• 2001

Rheumatoid arthritis (RA) is one of the most typical rheumatic diseases, and is characterized by chronic inflammation, cartilage destruction and joint deformity ［1,2］. During this process, profound hypertrophic changes of the synovium with infiltration of immune cells, increased vascularity, and hyperplasia result in the formation of a synovial pannus that invades cartilage and bone ［3］. In early stages of RA, the synovial membrane begins to invade the cartilage. In established RA, the synovial membrane becomes transformed into inflammatory tissue, the pannus (Fig. 1). The cell types that occupy cartilage-pannus junctions include synovial macrophages, fibroblasts, mast cells, polymorphonuclear lymphocytes (PMNs), and displaced, probably differentiated condrocytes ［4-6］. Recent studies of rheumatoid synovial tissue have demonstrated localized accumulations of mast cells and evidence of their activation/degranulation［7］.

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.552-552
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• 2001

Bacterial lipopolysaccharide (LPS) plays a major role in the development of periapical bone resorption. IL-1 and $TNF-{\alpha}$ are known to stimulate bone resorption and inhibit bone formation. Recent evidence has indicated that polymorphonuclear leukocytes (PMNs) have the ability to release IL-1 and $TNF-{\alpha}$ Calcium hydroxide is an effective medicament in root canal infections, reducing the microbial titre within the canal. It has been proposed that the therapeutic effect of $Ca(OH)_2$ may also be the result of direct inactivation of LPS.(omitted)

• Proceedings of the KACD Conference
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• 2001.11a
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• pp.562.1-562
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• 2001

Bacterial lipopolysaccharide (LPS) plays a major role in the development of periapical bone resorption. IL-1 and $TNF-{\alpha}$ are known to stimulate bone resorption and inhibit bone formation. Recent evidence has indicated that polymophonuclear leukocytes(PMNs) have the ability to release IL-1 and $TNF-{\alpha}$ Calcium hydroxide is an effective medicament in root canal infections, reducing the microbial titre within the canal. It has been proposed that the therapeutic effect of $CA(OH)_2$ may also be the result of direct inactivation of LPS.(omitted)

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.6
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• pp.874-885
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• 2012

In the present study, the possibility of whether the pharmacological effects of Scutellariae Radix Aqueous Extracts(SR) were favorably changed by report that lipopolysaccharide(LPS)-induced rat acute lung injury was treated with Red-Koji(Monascus purpureus 12002) fermentation. Three different dosages of Red-Koji fermented SR extract(fSR), 125, 250 and 500 mg/kg were orally administered once a day for 28 days before LPS(Escherichia coli 0111:B4) treatments, and then 5 hours after LPS treatment(500 ${\mu}g$/head, intra trachea instillation), all rats were sacrificed. Changes in the body weights, lung weights, pulmonary transcapillary albumin transit, arterial gas parameters(pH, $PaO_2$ and $PaCO_2$) bronchoalveolar lavage fluid(BALF) protein, lactate dehydrogenase(LDH) and proinflammatory cytokine tumor necrosis factor-${\alpha}$(TNF-${\alpha}$), interleukin-$1{\beta}$(IL-$1{\beta}$) contents, total cell numbers, neutrophil and alveolar macrophage ratios, lung malondialdehyde(MDA), myeloperoxidase(MPO), proinflammatory cytokine TNF-${\alpha}$ and IL-$1{\beta}$ contents were observed with histopathology of the lung, changes on luminal surface of alveolus(LSA), thickness of alveolar septum, number of polymorphonuclear neutrophils(PMNs). As results of LPS-injection, dramatical increases in lung weights, pulmonary transcapillary albumin transit increases in $PaCO_2$, decreases in pH of arterial blood and $PaO_2$, increases of BALF protein, LDH, TNF-${\alpha}$ and IL-$1{\beta}$ contents, total cells, neutrophil and alveolar macrophage ratios, lung MDA, MPO, TNF-${\alpha}$ and IL-$1{\beta}$ contents increases were detected with decreases in LSA and increases of alveolar septum and PMNs numbers, respectively as compared with intact control. Especially fSR 125 mg/kg showed quite similar favorable effects on the LPS-induced acute lung injuries as compared with 60 mg/kg of ${\alpha}$-lipoic acid and 250 mg/kg of SR. The results suggest that over 125 mg/kg of fSR extracts showed favorable effects on the LPS-induced acute lung injury mediated by their antioxidant and anti-inflammatory effects. Moreover, increases of the pharmacological effects of SR on LPS-induced acute lung injury were observed by Red-Koji fermentation in this study, at least 2-fold higher.

• Archives of Pharmacal Research
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• v.11 no.3
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• pp.203-212
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• 1988

To find antitumor components from the higher fungi of Korea, the mycelia of Favolus alveolarius (Fr.) Quelet were cultured in a liquid medium. The cultured mycelia were extracted with hot water twice, and a high molecular weight fraction was obtained by adding two volumes of ethanol to the extract. Two grams of Fraction A were obtained by dialyzing it. It was further separated into four fractions by gel filtration with Sepharose CL-4B, and they were designated Fractions B, C, D, and E. The results of the antitumor test showed that Fractions A, B, C, D and E had tumor inhibition ratios of 92.3, 78.5, 59.6, 77.4 and 62.2%, respectively. Anthrone test was carried out to determine the contents of total polysaccharide of the five fractions, and they had 46.3, 27.3, 65.3, 64.6, and 46.1%, respectively. The contents of the total protein of the five fractions were 29.4, 13.9, 14.3, 14.3, and 29.1%, respectively. Monosaccharide subunits of each fraction were analyzed with gas chromatography, and glucose, xylose, mannose, galactose and fucose were identified. Fraction A was examined for immunological effects. It increased the count of hemolytic plaque forming cells 12.8 times to that of the control group, and the population of macrophage in peritoneal cavity 3.2 times to that of the control group.

• BMB Reports
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• v.38 no.6
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• pp.661-667
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• 2005

Since conflicting results have been reported on non-specific immune response in type 1 diabetes, this study evaluates polymorphonuclear neutrophil (PMN) functions in the infection free Long Evan diabetic rats (type 1) by using tests that include: polarization assay, phagocytosis of baker's yeasts (Saccharomyces cerevisiae) and nitroblue tetrazolium (NBT) dye reduction. Polarization assay showed that neutrophils from diabetic rats were significantly activated at the basal level compared to those from the controls (p < 0.001). After PMN activation with N-formyl-methionyl-leucyl-phenylalanine (FMLP), control neutrophils were found to be more polarized than those of the diabetic neutrophils and the highest proportions of polarization were found to be 67% and 57% at $10^{-7}\;M$ FMLP, respectively. In the resting state, neutrophils from the diabetic rats reduced significantly more NBT dye than that of the controls (p < 0.001). The percentages of phagocytosis of opsonized yeast cells by the neutrophils from control and diabetic rats were 87% and 61%, respectively and the difference was statistically significant (p < 0.001). Evaluation of the phagocytic efficiency of PMNs revealed that control neutrophils could phagocytose $381{\pm}17$ whereas those from the diabetic rats phagocytosed $282{\pm}16$ yeast cells, and the efficiency of phagocytosis varied significantly (p < 0.001). Further, both the percentages of phagocytosis and the efficiency of phagocytosis by the diabetic neutrophils were inversely related with the levels of their corresponding plasma glucose (p = 0.02; r = -0.498 and p < 0.05; r = -0.43, respectively), which indicated that increased plasma glucose reduced the phagocytic ability of neutrophils. Such relationship was not observed with the control neutrophils. These data clearly indicate that PMN functions are altered in the streptozotocin (STZ) - induced diabetic rats, and hyperglycemia may be the cause for the impairment of their functions leading to many infectious episodes.