• Nutrition Research and Practice
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• v.10 no.6
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• pp.623-628
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• 2016

BACKGROUND/OBJECTIVES: Obesity-induced steatohepatitis accompanied by activated hepatic macrophages/Kupffer cells facilitates the progression of hepatic fibrinogenesis and exacerbates metabolic derangements such as insulin resistance. Heme oxyganase-1 (HO-1) modulates tissue macrophage phenotypes and thus is implicated in protection against inflammatory diseases. Here, we show that the flavonoid quercetin reduces obesity-induced hepatic inflammation by inducing HO-1, which promotes hepatic macrophage polarization in favor of the M2 phenotype. MATERIALS/METHODS: Male C57BL/6 mice were fed a regular diet (RD), high-fat diet (HFD), or HFD supplemented with quercetin (HF+Que, 0.5g/kg diet) for nine weeks. Inflammatory cytokines and macrophage markers were measured by ELISA and RT-PCR, respectively. HO-1 protein was measured by Western blotting. RESULTS: Quercetin supplementation decreased levels of inflammatory cytokines ($TNF{\alpha}$, IL-6) and increased that of the anti-inflammatory cytokine (IL-10) in the livers of HFD-fed mice. This was accompanied by upregulation of M2 macrophage marker genes (Arg-1, Mrc1) and downregulation of M1 macrophage marker genes ($TNF{\alpha}$, NOS2). In co-cultures of lipid-laden hepatocytes and macrophages, treatment with quercetin induced HO-1 in the macrophages, markedly suppressed expression of M1 macrophage marker genes, and reduced release of MCP-1. Moreover, these effects of quercetin were blunted by an HO-1 inhibitor and deficiency of nuclear factor E2-related factor 2 (Nrf2) in macrophages. CONCLUSIONS: Quercetin reduces obesity-induced hepatic inflammation by promoting macrophage phenotype switching. The beneficial effect of quercetin is associated with Nrf2-mediated HO-1 induction. Quercetin may be a useful dietary factor for protecting against obesity-induced steatohepatitis.

• Journal of Pharmacopuncture
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• v.11 no.1
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• pp.5-12
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• 2008

Objectives : Showing that Bong-Han corpuscles(BHC) are suppliers of the stem cells in adulthood, and the Bong-Han ducts(BHD) are transportation routes of stem cells. Methods : BHC and BHD were obtained from the internal organ-surfaces of rats. The sliced BHC and BHD were immunostained with various stem cell markers. Extracellular matrices were also analyzed by immunohistochemistry. Result : The presence of mesenchymal stem cells was confirmed by the expression of Integrin beta 1, Collagen type 1 and Fibronectin. But CD54 was not expressed. The hematopoietic stem cell marker, Thy 1 was strongly expressed. BHDs showed Collagen type 1, Fibronectin, and vWF expression. Conclusion : Both hematopoietic and mesenchymal stem cell markers were expressed strongly in BHC similarly as in bone marrow. An endothelial cell marker(vWF) demonstrated the possibility of the stem cell transportation routes of BHD.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.5C
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• pp.351-360
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• 2008

In cellular mobile radio systems with frequency reuse, the interference signals degrade the channel estimation and signal detection performance due to the low signal-to-interference ratio near coverage boundaries. When the preamble pilot sequences from different cells are orthogonal or located in disjointed positions, they can be used for multi-cell channel estimation and interference cancellation. In time-varying channels caused by Doppler spread, data pilot symbols are needed for channel estimations. However, data pilot symbols are usually located in identical positions for the overhead reduction, which degrades the channel estimation performance. In this paper, we demonstrate a significant amount of performance improvement is achieved by multiplying different pseudonoise(PN) sequences to the data pilot symbols from adjacent interference cells. In particular, for detection scheme using maximal ratio combining(MRC) and inter-cell spatial demultiplexing(ISD), quantitative performance gain of spectral efficiency for different values of Doppler frequency and interference power is presented.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.661-667
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• 2001

This paper proposes a Truncated Type-II Hybrid ARQ scheme using an adaptive modulation system to achieve high throughput data transmission systems for DS-CDMA cellular mobile communication systems. In this paper, the adaptive modulation system analyzed in Nakagami (m-distribution) fading channel environment. The adaptive modulation system controls the modulation level and symbol rate according to the Nakagami fading parameter( m). When the received Eb/No is high or the Nakagami fading parameter m is high, the propose system selects higher modulation level and higher symbol rate to increase throughput. On the other hand, this system selects lower modulation level and lower symbol rate to prevent throughput performance degradation when the received Eb/No is low. The modulation method have been adopted QPSK 16QAM, 64QAM, 256QAM. Therefore, adaptive modulation systems with Truncated Type II Hybrid ARQ Scheme is proper for mobile and radio data communication system that require high reliability and delay-limited applications.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.5
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• pp.122-130
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• 2008

Improving the transmission rates of multi-media delivery, such as moving pictures and internet services, has become increasingly important in modern society. To satisfy such high data rate requirements, the MIMO technique, which has the capacity to transmit large amounts of data using limited frequency resources, was developed. The Space Division Multiplexing (SDM) system is one of the MIMO techniques to be able to improve the transmission capacity. However, it is unable to achieve diversity gain because of interference due to the use of multiple antennas. In this paper, an SDM system that utilizes a Multi-Block method as an advanced transmission technique in a wireless communication system to obtain diversity gain is proposed and discussed fur the performance of the proposed system.

• Journal of Life Science
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• v.26 no.11
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• pp.1320-1329
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• 2016

The present study examined the cytotoxic effects of 1, 2, 3, 4, 6-penta-O-galloyl-${\beta}$-D-glucose (PGG), known as the pentahydroxy gallic acid ester of glucose, in the various human cancer cell lines (A-549, MDA-MB-231, U87-MG, MCF-7 and PANC-1), normal MRC-5 fetal fibroblasts, and dental papilla tissue- derived mesenchymal stem cells (DPSCs). Significantly (p<0.05) lower half maximal inhibitory concentration ($IC_{50}$) values were observed in the A-549 and MDA-MB-231 cells showing a high proliferation capacity, compared with other cancer and normal cell lines with a relatively low proliferation capacity. The population doubling time (PDT) was significantly (p<0.05) higher in the $10{\mu}M$ PGG-treated cell lines than those of untreated control cell lines. The present study demonstrated that the $IC_{50}$ value increases proportionally to the extending PDT. A high cell number with senescence-associated ${\beta}-galactosidase$ activity was also observed in the $10{\mu}M$ PGG-treated cells compared with those of untreated control cells. Moreover, the level of telomerase activity was significantly (p<0.05) decreased with $10{\mu}M$ PGG treatment, especially in A-549 and MDA-MB-231 cells showing a high proliferation capacity. Based on these observations, PGG could serve as a potent agent for cancer chemotherapy, as its treatment was more effective in cells with a high proliferation capacity.

• The Journal of Advanced Prosthodontics
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• v.7 no.2
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• pp.138-145
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• 2015

PURPOSE. The objective of this study was to conduct an in vitro comparative evaluation of polished and laser-dimpled titanium (Ti) surfaces to determine whether either surface has an advantage in promoting the attachment of epithelial-like cells and fibroblast to Ti. MATERIALS AND METHODS. Forty-eight coin-shaped samples of commercially pure, grade 4 Ti plates were used in this study. These discs were cleaned to a surface roughness (Ra: roughness centerline average) of 180 nm by polishing and were divided into three groups: SM (n=16) had no dimples and served as the control, SM15 (n=16) had $5-{\mu}m$ dimples at $10-{\mu}m$ intervals, and SM30 (n=16) had $5-{\mu}m$ dimples at $25-{\mu}m$ intervals in a $2{\times}4mm^2$ area at the center of the disc. Human gingival squamous cell carcinoma cells (YD-38) and human lung fibroblasts (MRC-5) were cultured and used in cell proliferation assays, adhesion assays, immunofluorescent staining of adhesion proteins, and morphological analysis by SEM. The data were analyzed statistically to determine the significance of differences. RESULTS. The adhesion strength of epithelial cells was higher on Ti surfaces with $5-{\mu}m$ laser dimples than on polished Ti surfaces, while the adhesion of fibroblasts was not significantly changed by laser treatment of implant surfaces. However, epithelial cells and fibroblasts around the laser dimples appeared larger and showed increased expression of adhesion proteins. CONCLUSION. These findings demonstrate that laser dimpling may contribute to improving the peri-implant soft tissue barrier. This study provided helpful information for developing the transmucosal surface of the abutment.

• The Journal of Korean Society of Virology
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• v.29 no.1
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• pp.11-22
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• 1999

Sero-epidemiologic survey has been carried out to establish serologically the presence of hantavirus in areas of South Africa. The survey was oriented to search natural infection in both of humans and wild rodents and involvement of human disease. The normal human sera were collected from the residents in urban and rural areas of Western Cape, and rural area of Eastern Cape province. The rodent sera came from various species of rodents trapped in Northern Cape and Western Free provinces. The patient sera were selected from the patients of renal failure, pulmonary syndrome and pyrexia of unknown origin (PUQ) according to diagnostic chart among the patients hospitalized in major hospitals of Cape Town area. The sera were screened and titrated by IFA test using antigens of Hantaan (HTN), Seoul (SEO), Puumala (PUU), and Prospect Hill (PH) viruses primarily. Positive cases were subjected to differential IFA test using HTN, PUU and PH antigens and plaque reduction neutralization test for further confirmation. Anti-hantavirus antibodies were detected from 2 of 352 rural, 1 of 172 urban residents of E. Cape, and 5 of 118 rural, 5 of 368 urban residents of W. Cape. The antibody was also demonstrated from 5 of 221 wild rodents, and it was appeared that 2 different species, Aethomys namaquensis and Tatem leucogaster, are involved. Among 318 patients tested, 3 who were diagnosed as chronic renal failure, acute respiratory distress syndrome (ARDS) and glomerulonephritis were proved to be positive. The reaction patterns obtained from all of these positive sera were distinct from hantaviral sero-patterns ever established. This result suggests that new viruses may exist in this area and play an possible etiologic role in human disease. The feature of serologic survey on anti-hantavirus antibody demonstrable newly from African wild rodents which are different from reservoir species in other continents elicits a conjecture that the virus may be different from known hantaviruses ever found. This fact also suggests that an expanded role in etiologic involvement with other unknown human diseases by newly emerging hantaviruses may be possible in this areas.

• Tuberculosis and Respiratory Diseases
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• v.60 no.4
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• pp.397-403
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• 2006

Background: Chronic obstructive pulmonary disease(COPD) is categorized by the percentage of the predicted $FEV_1$(Forced expiratory volume in 1 second) result which is highly correlated with disease severity(morbidity and mortality). In COPD patients, dyspnea seems to be different from disease severity. We investigated whether dyspnea is correlated with disease severity, as measured by $FEV_1$, quality of life(QoL), occupation, and supporting level of family members and neighbors. Method: Thirty-six clinically stable patients with chronically irreversible airflow limitation were enrolled. We used the Medical Research Council(MRC) dyspnea scale to assess the level of dyspnea and the Korean St. Goerge's respiratory questionnaire(SGRQ) as measure the QoL. Result: The mean percentage of the predicted $FEV_1$ was 32.0%. Dyspnea was not correlated with GOLD stage using $FEV_1$(p=0.114). With deteriorating level of dyspnea the scores of symptoms(p=0.041), activity(p=0.004), impact(p=0.001), and total SGRQ score(p<0.001) were significantly increased. Dyspnea was not correlated with the level of occupation(p=0.259). The supporting level of family members and neighbors was significantly negatively correlated with dyspnea scale(p=0.011). Conclusion: In the management of COPD patients, we have to remember that the level of subjective dyspnea is correlated with QoL(symptom, activity and impact on society) and social supporting level as well as GOLD stage($FEV_1$).

• Journal of Life Science
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• v.31 no.11
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• pp.1028-1036
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• 2021

Firefly luciferase (FLuc) can function as an efficient marker in the gene and viral therapies. Nonetheless, its clinical translation has been unaccomplished with the concerns on its exogenous nature and the similarity with human fatty acyl-CoA synthetase. In this study, we aimed to show safety of FLuc by conducting a set of preclinical experiments and a human use. Initially, FLuc permeability across the plasma membrane was investigated by delivering the FLuc-carrying viral vector, OTS-412, or the FLuc recombinant protein. After in vitro infection of OTS-412 into different cancer cell lines, FLuc activity was detected only in the cell lysates, but not in culture media. In addition, recombinant FLuc protein further showed the impermeability against the plasma membrane. Similar result was also observed in the in vivo experiment. After being injected into the VX2 tumor-bearing rabbit, the FLuc exclusively resided within the tumor tissue without being detected in the blood plasma or other organs. Human cancer cell lines originated from various organs were lysed and treated to the FLuc, and none of the human substrates was reactive against the FLuc. As a final step, FLuc recombinant protein was intravenously injected into a human. The luciferase was degraded with the half-life of 20 to 30 minutes in blood, and was untraceable from 1.5 hr after the injection. In addition, the blood plasma was nonresponsive against the fatty acids. Hematological analysis was also comparable between the pre- and post-injection. Altogether, our study collectively demonstrates the safety of the firefly luciferase.