• Korean Journal of Materials Research
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• v.32 no.6
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• pp.293-300
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• 2022

This study investigated a graded-refractive-index (GRIN) coating pattern capable of improving the light extraction efficiency of GaN light-emitting diodes (LEDs). The planar LEDs had total internal reflection thanks to the large difference in refractive index between the LED semiconductor and the surrounding medium (air). The main goal of this paper was to reduce the trapped light inside the LED by controlling the refractive index using various compositions of (TiO₂)_x(SiO₂)_1-x in GRIN LEDs consisting of five dielectric layers. Several types of multilayer LEDs were simulated and it was determined the transmittance value of the LEDs with many layers was greater than the LEDs with less layers. Then, the specific ranges of incident angles of the individual layers which depend on the refractive index were evaluated. According to theoretical calculations, the light extraction efficiency (LEE) of the five-layer GRIN is 25.29 %, 28.54 % and 30.22 %, respectively. Consequently, the five-layer GRIN LEDs patterned enhancement outcome LEE over the reference planar LEDs. The results suggest the increased light extraction efficiency is related to the loss of Fresnel transmission and the release of the light mode trapped inside the LED chip by the graded-refractive-index.

• IMMUNE NETWORK
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• v.23 no.2
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• pp.14.1-14.14
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• 2023

Immune status including the immune cells and cytokine profiles has been implicated in the development of endometriosis. In this study, we analyzed Th17 cells and IL-17A in peritoneal fluid (PF) and endometrial tissues of patients with (n=10) and without (n=26) endometriosis. Our study has shown increased Th17 cell population and IL-17A level in PF with endometriosis patients. To determine the roles of IL-17A and Th17 cells in the development of endometriosis, the effect of IL-17A, major cytokine of Th17, on endometrial cells isolated from endometriotic tissues was examined. Recombinant IL-17A promoted survival of endometrial cells accompanied by increased expression of anti-apoptotic genes, including Bcl-2 and MCL1, and the activation of ERK1/2 signaling. In addition, treatment of IL-17A to endometrial cells inhibited NK cell mediated cytotoxicity and induced HLA-G expression on endometrial cells. IL-17A also promoted migration of endometrial cells. Our data suggest that Th17 cells and IL-17A play critical roles in the development of endometriosis by promoting endometrial cell survival and conferring a resistance to NK cell cytotoxicity through the activation of ERK1/2 signaling. Targeting IL-17A has potential as a new strategy for the treatment of endometriosis.

• Genomics & Informatics
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• v.7 no.1
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• pp.20-25
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• 2009

Rheumatoid arthritis (RA) is a chronic autoimmune disorder that is characterized by inflammation of the synovial tissue and deterioration of the joint and bone. A recent study reported a potential gene-environment interaction between HLA-DR and smoking. The present study investigated whether a specific gene was related to the association between smoking and the severity of RA (rheumatoid factor levels > 20 IU/ml). We used the resources of the NARAC family collection of GAW 15 databases, and 1139 subjects with RF>20 IU/ml were included in the current analysis. The linkage panel contained 5858 SNP markers, and 5744 SNPs passed quality control criteria. Linear regression analyses, using PLINK software and generalized estimating equation regression models, were used to test for associations between the SNPs and the severity of RA according to smoking groups. Two major findings were established. First, the severity of RA in smokers was associated with rs703618 (p=$6{\times}10^{-5}$), which lies in the intronic region of the stabilin 2 (STAB2) gene on chromosome 12. Second, there were significant differences in the levels of RF between 'ever smokers' and 'never smokers' according to the rs703618 genotype (G/G, A/G, A/A). We investigated whether a specific gene acts as a mediator between smoking and the severity of RA and found that the STAB2 gene could affect this relationship. Our finding indicates that smoking may mediate RA severity by affecting the expression level of a specific gene.

• Korean Journal of Clinical Laboratory Science
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• v.40 no.2
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• pp.106-112
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• 2008

Bone marrow derived mesenchymal stem cells (BMSCs) are largely studied for their potential clinical use. But it is hard to get enough number of those cells for clinical trials and give serious pain to the patients. Adipose tissue is derived from the embryonic mesenchyme and contains a stroma that is easily isolated with large amount. This cell population (adipose derived stem cells: ADSCs) can be isolated from human lipoaspirates and like MSCs, differentiate toward the osteogenic, adipogenic, myogenic and chondrogenic lineages. To confirm whether adipose tissue contains stem cells, the ADSCs extracted from omental or subcutaneous fat tissue were expanded during third to fifth passages. The phenotype of the ADSCs was identified by the conventional cell surface markers using flow cytometry: positive for CD29 and CD44, but negative for CD34, CD45, CD117 and HLA-DR that similar to those observed on BMSCs. The ADSCs were able to differentiate into the osteoblast or adipocytes with induction media. Finally, ADACs expressed multiple CD marker antigens similar to those observed on BMSCs and differentiated into osteoblast, adipocyte. With this, human adipotissue contains multipotent cells and may represent an alternative stem cell source to bone marrow-derived MSCs.

• IMMUNE NETWORK
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• v.4 no.1
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• pp.31-37
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• 2004

Background: 1-8D gene is a member of human 1-8 interferon inducible gene family and is shown to be overexpressed in fresh colon cancer tissues. Three peptides 1-6, 3-5 and 3-7 derived from 1-8D gene were shown to have immunogenicity against colon cancer. Methods: To study tumor immunotherapy of these peptides we established an adoptive transfer model. $D^{b-/-}{\times}{\beta}2$ microglobulin (${\beta}2m$) null mice transgenic for a chimeric HLA-A2.1/$D^b-{\beta}2m$ single chain (HHD mice) were immunized with irradiated peptide-loaded RMA-S/HHD/B7.1 transfectants. Spleens were removed after last immunization, and splenocytes were re-stimulated in vitro. Lymphocytes from vaccinated HHD mice were transferred together with IL-2 to the tumor bearing nude mice that were challenged S.C. with the HCT/HHD/B7 colon carcinoma cell line that was found to grow in these mice. Results: Peptide 3-5 was found to be highly effective in CTL activity. Adoptively transferred anti-peptide 3-5 cytolytic T lymphocytes caused significant retardation in tumor growth. Conclusion: This study shows that peptide 3-5 can be the most effective candidate for the vaccine of adoptive immunotherapy against colon cancer.

• Archives of Plastic Surgery
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• v.50 no.4
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• pp.432-442
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• 2023

Background Macrophages play a major role in wound healing and prevent infection from the outside. Polarization conversion of macrophages regulates aspects of inflammation, and two macrophages, M1 (classically activated) and M2 (alternatively activated), exist at both ends of broad-spectrum macrophage polarization. Thus, we aimed to investigate whether macrophage polarization can be artificially regulated. To this end, MgSO4 and small-interfering RNA (siRNA) targeting magnesium transport 1 (MAGT1) were used to investigate the effects of intracellular magnesium (Mg2+) concentrations on the differentiation of macrophages in vitro. Methods THP-1 derived macrophages maintained in a culture medium containing 5 mM MgSO4 and siRNA to inhibit the expression of MAGT1. As comparative groups, THP-1 derived macrophages polarized into M1 and M2 macrophages by treatment with M1, M2 inducer cytokine. The polarization status of each group of cells was confirmed by cell surface antigen expression and cytokine secretion. Results We found that MgSO4 treatment increased CD163 and CD206, similar to the effect noted in the M2 group. The expression of CD80 and HLA-DR was increased in the group treated with MAGT1 siRNA, similar to the effect noted in the M1 group. Functional assays demonstrated that the group treated with MgSO4 secreted higher levels of IL-10, whereas the MAGT1 siRNA-treated group secreted higher levels of IL-6 cytokines. Additionally, the conditional medium of the Mg2+ treated group showed enhanced migration of keratinocytes and fibroblasts. Conclusion Mg2+ can help to end the delay in wound healing caused by persistent inflammation in the early stages.

• IMMUNE NETWORK
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• v.5 no.3
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• pp.157-162
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• 2005

Background: 1-8D gene is a member of human 1-8 interferon inducible gene family and was shown to be overexpressed in fresh colon cancer tissues. Three peptides 1-6, 3-5 and 3-7 derived from human 1-8D gene were shown to have immunogenicity against colon cancer. Methods: To study tumor immunotherapy, of three peptides we established an active immunization model using HHD mice. $D^{b-/-}{\times}{\beta}2$ microglobulin $({\beta}2m)$ null mice transgenic for a chimeric HLA-$A2.1/D^{b-}\;{\beta}2m$ single chain (HHD mice) were challenged with B16/HHD/1-8D tumor cells and were immunized with irradiated peptide-loaded RMA- S/HHD/B7.1 transfectants. In therapy model tumor growth was retarded in HHD mice that were injected with 3-5 peptide-loaded RMA-S/HHD/B7.1. In survival test vaccination with 1-8D-derived peptide protects HHD mice from tumor progression after tumor challenge. Results: These studies show that peptide 3-5 derived from 1-8D gene can be the most effective candidate for the vaccine of immunotherapy against colon cancer and highlight 1-8D gene as putative colon carcinoma associated antigens. Conclusion: We demonstrated that RMA-S/HHD/ B7.1 loaded with 1-8D peptides, especially 3-5, immunization generates potent antitumor immunity against tumor cells in HHD mice and designed active immunization as proper immunotherapeutic protocols.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.203-203
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• 2002

Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-α/β) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2′, 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-α and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.

• Journal of Microbiology
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• v.38 no.4
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• pp.203-208
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• 2000

Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-$\alpha$/$\beta$) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2', 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-$\alpha$ and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.

• Korean Journal of Agricultural Science
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• v.46 no.1
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• pp.183-194
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• 2019

Adulteration of argan oil with some other cheaper oils with similar chemical compositions has resulted in increasing demands for authenticity assurance and quality control. Fast and simple analytical techniques are thus needed for authenticity analysis of high-priced argan oil. Raman spectroscopy is a potent technique and has been extensively used for quality control and safety determination for food products In this study, Raman spectroscopy in combination with a net analyte signal (NAS)-based methodology, i.e., hybrid linear analysis method developed by Goicoechea and Olivieri in 1999 (HLA/GO), was used to predict the different concentrations of olive oil (0 - 20%) added to argan oil. Raman spectra of 90 samples were collected in a spectral range of $400-400cm^{-1}$, and calibration and validation sets were designed to evaluate the performance of the multivariate method. The results revealed a high coefficient of determination ($R^2$) value of 0.98 and a low root-mean-square error (RMSE) value of 0.41% for the calibration set, and an $R^2$ of 0.97 and RMSE of 0.36% for the validation set. Additionally, the figures of merit such as sensitivity, selectivity, limit of detection, and limit of quantification were used for further validation. The high $R^2$ and low RMSE values validate the detection ability and accuracy of the developed method and demonstrate its potential for quantitative determination of oil adulteration.