• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.367-369
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• 2002

본 논문은 GRID 상에서 HLA(High Level Architecture)를 기반으로 한 분산 객체 지향 wargame simulation의 디자인과 구현에 관해 기술한다. HLA는 DIS[1]의 뒤를 이어 제안된 아키텍처로서 simulation에 원활한 data교류와 동기화를 제공한다. 또한, GRID는 전세계에 펼쳐져 있는 자원들에 대한 관리와 접근, 사용을 위한 다양한 기능과 안전하고 편리한 security를 보장한다. 본 논문에서는 HLA를 사용해서 simulation에 튀어난 상호 연동 능력과 재사용성을 부여하고, GRID를 통해 대규모의 프로젝트를 위한 광범위한 자원을 보다 안전하고 효율적으로 사용할 수 있도록 하는 환경을 구현하였다. 우리는 이 simulation을 HDOWS-G(HLA-based Distributed Object-oriented War game Simulation on Grid)라 부르기로 한다.

• Structural Engineering and Mechanics
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• v.82 no.2
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• pp.245-258
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• 2022

Many Structural Health Monitoring (SHM) methods have been proposed for structural damage diagnosis and prognosis. However, SHM for pinched hysteretic structures can be problematic due to the high level of nonlinearity. The model-free hysteresis loop analysis (HLA) has displayed notable robustness and accuracy in identifying damage for full-scaled and scaled test buildings. In this paper, the performance of HLA is compared with seven other SHM methods in identifying lateral elastic stiffness for a six-story numerical building with highly nonlinear pinching behavior. Two successive earthquakes are employed to compare the accuracy and consistency of methods within and between events. Robustness is assessed across sampling rates 50-1000 Hz in noise-free condition and then assessed with 10% root mean square (RMS) noise added to responses at 250 Hz sampling rate. Results confirm HLA is the most robust method to sampling rate and noise. HLA preserves high accuracy even when the sampling rate drops to 50 Hz, where the performance of other methods deteriorates considerably. In noisy conditions, the maximum absolute estimation error is less than 4% for HLA. The overall results show HLA has high robustness and accuracy for an extremely nonlinear, but realistic case compared to a range of leading and recent model-based and model-free methods.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5399-5403
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• 2012

Aims and Background: Human leukocyte antigen-G and interleukin-2 receptor play pivotal roles in the proliferation of lymphocytes, and thus generation of immune responses. Their overexpression has been evidenced in different malignant hematopoietic diseases. This study aimed to validate serum soluble human leukocyte antigen-G (sHLA-G) and serum soluble interleukin-2 receptor (sIL-2R) as an additional tool for the diagnosis and follow up of acute lymphoblastic leukemia (ALL). Subjects and Methods: Both markers were determined by ELISA in the serum of 33 ALL pediatric patients before treatment and after intensification phase of chemotherapy as well as in the serum of 14 healthy donors that were selected as a control group. Results: ALL patients showed abnormal CBC and high serum lactate dehydrogenase, which were improved after chemotherapy. Also, there was a non-significant increase in serum sHLA-G in ALL patients compared with the control group. However, after chemotherapy, sHLA-G was increased significantly compared with before treatment. On the other hand, serum sIL-2R in ALL patients was increased significantly compared with the control group. After chemotherapy, sIL-2R decreased significantly compared with before treatment. Conclusions: From these results it could be suggested that measurement of serum sHLA-G might be helpful in diagnosis of ALL, while sIL-2R might be useful in diagnosis and follow-up of ALL in pediatric patients.

• IMMUNE NETWORK
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• v.2 no.4
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• pp.227-232
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• 2002

Background: Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by diverse clinical manifestations and autoantibody production, which is known to be strongly influenced by genetic factors. Previous studies have revealed the associations of SLE with HLA class II alleles and antiphospholipid antibody system (anticardiolipin antibody (aCL) and anti-${\beta}_2$ glycoprotein I antibody (anti-${\beta}_2$ GPI)). Therefore, we studied the associations of HLA class II alleles with SLE and antiphospholipid antibody system. Methods: The genotyping for HLA-DRB1 and DQB1 alleles were performed in 61 SLE patients and 100 controls by the polymerase chain reaction (PCR)-sequence specific oligonucleotide probe method. ELISA tests for aCL and anti-${\beta}_2$ GPI were performed in 39 of the 61 SLE patients. The results were evaluated statistically by Chi-square test. Results: The frequencies of the HLA-$DRB1^*15$ and $DQB1^*06$ in SLE patients were significantly higher than those in controls. HLA-$DRB1^*12$ was significantly lower in SLE patients than controls. Nine of 39 patients were positive for aCL (IgG) and three were positive for aCL (IgM). One of 39 patients were positive for anti-${\beta}_2$ GPI (IgG) and none of them positive for anti-${\beta}_2$ GPI (IgM). Association of aCL with HLA class II alleles was not observed in our study. Conclusion: According to our results, it was found that HLA-$DRB1^*15$ and $DQB1^*06$ were associated with genetic susceptiblility and $DRB1^*12$ was associated with resistance to SLE in Korean population. No Association of aCL with HLA class II alleles was observed and the positive rate for anti-${\beta}_2$ GPI was very low.

• Development and Reproduction
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• v.5 no.2
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• pp.93-100
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• 2001

Precise mechanism by which the fetus can escape from mother's immune rejection is not well understood yet over the last 50 years. The clarification of immune mechanism at the feto-maternal interface is very important, because this can be a common pathogenesis of various pathologic conditions including spontaneous abortion, habitual abortion fetal growth restriction preeclampsia, implantation failure after assisted reproductive techniques, and fetal death. In this review, current hypothetical contents were described with the priority of importance: 1) The center of this mechanism is cross-talk between the expression of HLA-C, E, G on the extravillous cytotrophoblasts and their receptors on decidual NK cell, 2) immunomodulation, 3) innate immunity is the main immunologic mechanism, 4) various mechanisms besides HLA system(eq. complement) may be associated. The overall balance of immunomodulation among these mechanisms should result in the outcome of each pregnancy. Further researches regarding the regulation of HLA system, roles of cytokines, complements should be followed in the future.

• Molecules and Cells
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• v.39 no.4
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• pp.286-291
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• 2016

Epstein-Barr virus (EBV) is the prototypical ${\gamma}$-herpesvirus and an obligate human pathogen that infects mainly epithelial cells and B cells, which can result in malignancies. EBV infects these target cells by fusing with the viral and cellular lipid bilayer membranes using multiple viral factors and host receptor(s) thus exhibiting a unique complexity in its entry machinery. To enter epithelial cells, EBV requires minimally the conserved core fusion machinery comprised of the glycoproteins gH/gL acting as the receptor-binding complex and gB as the fusogen. EBV can enter B cells using gp42, which binds tightly to gH/gL and interacts with host HLA class II, activating fusion. Previously, we published the individual crystal structures of EBV entry factors, such as gH/gL and gp42, the EBV/host receptor complex, gp42/HLA-DR1, and the fusion protein EBV gB in a postfusion conformation, which allowed us to identify structural determinants and regions critical for receptor-binding and membrane fusion. Recently, we reported different low resolution models of the EBV B cell entry triggering complex (gHgL/gp42/HLA class II) in "open" and "closed" states based on negative-stain single particle electron microscopy, which provide further mechanistic insights. This review summarizes the current knowledge of these key players in EBV entry and how their structures impact receptor-binding and the triggering of gB-mediated fusion.

• IMMUNE NETWORK
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• v.2 no.4
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• pp.248-255
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• 2002

Background: TAP1 and TAP2 are two ABC transporter genes located within the class II region of the human MHC. Their protein products form a heterodimer whose function is to transport peptides from the cytoplasm into the endoplasmic reticulum. This study was performed to examine the polymorphism of TAP genes and the distribution of HLA-TAP haplotypes in the Korean population through family analysis. Methods: The subjects used in this study were 50 healthy Korean families consisting of 233 individuals. TAP1 (codons 333 and 637) and TAP2 (codons 379, 565, 577, 651, 665, and 687) typings were carried out by the PCR-restriction fragment length polymorphism (RFLP) method. HLA-DRB1 and DQB1 genotyping results from a previous study were used for HLA-TAP haplotype analysis. Results: The number (gene frequency) of TAP1 and TAP2 alleles detected were 3 for TAP1 (A 81.5%, B 17.0%, and C 1.5%) and 8 for TAP2 (A1 32.0%, A2 12.5%, B 34.0%, Bky2 6.5%, C 7.0%, D 3.0%, E 4.5%, and G 0.5%). Eleven TAP1-TAP2 haplotypes were observed with $frequency{\geq}1%$, among which 4 haplotypes (A-B, B-A1, A-Bky2, and C-E) showed weak but significant positive linkage disequilibrium (P<0.05). When DRB1-DQB1 haplotypes were extended to TAP1 and TAP2 loci, much diversification of haplotypes was observed: 19 different DRB1-DQB1 haplotypes formed 58 different haplotypes extended to TAP1 and TAP2 loci. These results add more evidence to the view that recombination hotspot is present within and around TAP gene region. Conclusion: The allele frequencies of TAP1 and TAP2 genes and the distribution of TAP1-TAP2 and HLA-TAP haplotypes were studied in Koreans based on a family study.

• BMB Reports
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• v.43 no.4
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• pp.250-256
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• 2010

Natural phosphodiester bond CpG-DNA that contains immunomodulatory CpG motifs (PO-DNA) upregulates the expression of proinflammatory cytokines and induces an Ag-driven Th1 response in a CG sequence-dependent manner in mice. In humans, only phosphorothioate backbone-modified CpG-DNA (PS-DNA) and not PO-DNA has immunomodulatory activity. In this study, we found that liposome-encapsulated PO-DNA upregulated the expression of human $\beta$-defensin-2 (hBD-2) and major histocompatibility class II molecules (HLA-DRA) in a CG sequence-dependent and liposome- dependent manner in human B cells. Of the three different liposomes, DOTAP has the unique ability to enhance the immunomodulatory activity of PO-DNA. In contrast, HLA-DRA and hBD-2 promoter activation can be induced by liposome-encapsulated PS-DNA in a CG sequence-independent manner, depending on the CpG-DNA species. Our observations demonstrate that, when encapsulated with a proper liposome in the immune system, natural PO-DNA has the potential to be a useful therapy for the regulation of the innate immune response.

• Development and Reproduction
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• v.14 no.3
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• pp.155-162
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• 2010

The trophectoderm is one of the earliest cell types to differentiate in the forming placenta. It is an important for the initial implantation and placentation during pregnancy. Trophoblast stem cells (TBSCs) develop from the blastocyst and are maintained by signals emanating from the inner cell mass. However, several limitations including rarity and difficulty in isolation of trophoblast stem cells derived from blastocyst still exist. To establish a model for trophoblast differentiation, we isolated TBSCs from human term placenta ($\geq$38 weeks) and characterized. Cell cycle was analyzed by measuring DNA content by FACS analysis and phenotype of TBSCs was characterized by RT-PCR and FACS analysis. TBSCs have expressed various markers such as self-renewal markers (Nanog, Sox2), three germ layer markers (hNF68, alpha-cardiac actin, hAFP), trophoblast specific markers (CDX-2, CK7, HLA-G), and TERT gene. In FACS analysis, TBSCs isolated from term placenta showed that the majority of cells expressed CD13, CD44, CD90, CD95, CD105, HLA-ABC, cytokeratin 7, and HLA-G. Testing for CD31, CD34, CD45, CD71, vimentin and HLA-DR were negative. TBSCs were shown to decrease the growth rate when cultured in conditioned medium without FGF4/heparin as well as the morphology was changed to a characteristic giant cell with a large cytoplasm and nucleus. In invasion assay, TBSCs isolated from term placenta showed invasion activities in in vivo using nude mice and in vitro Matrigel system. Taken together, these results support that an isolation potential of TBSCs from term placenta as well as a good source for understanding of the infertility mechanism.

• IMMUNE NETWORK
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• v.2 no.4
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• pp.242-247
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• 2002

Background: Tumor necrosis factor-alpha (TNF-$\alpha$) is known to play an important role in various conditions such as inflammation, autoimmunity, apoptosis, insulin resistance and sleep induction. Five single nucleotide polymorphisms (SNPs) have been known to affect the transcriptional activities of TNF-$\alpha$: -1,031T/C, -863C/A, -857C/T, -308G/A and -238G/A. Methods: We have investigated 5 SNPs of the promoter region of TNF-$\alpha$ gene, the distribution of 5-locus TNF-$\alpha$ haplotypes, and their haplotypic associations with previously typed HLA-A, -B and -DRB1 loci in 107 healthy unrelated Koreans. TNF-$\alpha$ SNPs were typed using PCR-single-strand conformation polymorphism (SSCP) and PCR-restriction fragment length polymorphism (RFLP) methods. Results: The allele frequencies of -1,031C, -863A, -857T, -308A, and-238A, which are known as the high-producer-type, were 19.3%, 15.9%, 14.0%, 5.9%, and 2.9%, respectively. The frequency of -308A allele, known to be associated with autoimmune diseases, was 5.9% in Koreans which was lower than Caucasians (14~17%) and somewhat higher than Japanese (1.7%). Five most common TNF-$\alpha$ haplotypes (-1,031/-863/-857/-308/-238) comprised over 95% of total haplotypes: TCCGG (58.4%), CACGG (14.8%), TCTGG (13.7%), TCCAG (5.3%), and CCCGA (3.1%). Strong positive associations (P<0.001) were observed between TCCGG and B62; between CACGG and B51, $DRB1^*0901$; between TCTGG and B35, B54, B59, $DRB1^*1201$; and between TCCAG and A33, B58, $DRB1^*0301$, $DRB1^*1302$. Five most common extended haplotypes (>3%) comprised around 16% of total haplotypes: A33-B58-TCCAG-$DRB1^*1302$, A24-B52-TCCGG-$DRB1^*1502$, A33-B44-TCCGG-$DRB1^*1302$, A24-B7-TCCGG-$DRB1^*0101$, and A11-B62-TCCGG-$DRB1^*0406$. The distribution of extended HLA and TNF-$\alpha$ haplotypes showed that most of HLA haplotypes were almost exclusively associated with particular TNF-$\alpha$ haplotypes. Conclusion: The results obtained in this study would be useful as basic data for anthropologic studies and disease association studies in Koreans.