• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.6
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• pp.252-259
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• 2005

Single crystal $CuGaSe_2$ layers were grown on thoroughly etched semi-insulating CaAs(100) substrate at $450^{\circ}C$ with hot wall epitaxy (HWE) system by evaporating $CuGaSe_2$ source at $610^{\circ}C$. The crystalline structure of the single crystal thin films was investigated by the photoluminescence (PL) and double crystal X-ray diffraction (DCXD). The carrier density and mobility of single crystal $CuGaSe_2$ thin films measured with Hall effect by Van der Pauw method are $4.87{\times}10^{17}cm^{-3}$ and $129cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CuGaSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=1.7998eV-(8.7489{\times}10^{-4}eV/K)T^2/(T+335K)$. The voltage, current density of maxiumun power, fill factor, and conversion, efficiency of $n-CdS/p-CuGaSe_2$, heterojunction solar cells under $80mW/cm^2$ illumination were found to be 0.41 V, $21.8mA/cm^2$, 0.75 and 11.17%, respectively.

• IMMUNE NETWORK
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• v.11 no.1
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• pp.79-94
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• 2011

Background: Dendritic cell (DC)-based vaccines are currently being evaluated as a novel strategy for tumor vaccination and immunotherapy. However, inducing long-term regression in established tumor-implanted mice is difficult. Here, we show that deoxypohophyllotoxin (DPT) induces maturation and activation of bone marrow-derived DCs via Toll-like receptor (TLR) 4 activation of MAPK and NF-${\kappa}B$. Methods: The phenotypic and functional maturation of DPT-treated DCs was assessed by flow cytometric analysis and cytokine production, respectively. DPT-treated DCs was also used for mixed leukocyte reaction to evaluate T cell-priming capacity and for tumor regression against melanoma. Results: DPT promoted the activation of $CD8^+$ T cells and the Th1 immune response by inducing IL-12 production in DCs. In a B16F10 melanoma-implanted mouse model, we demonstrated that DPT-treated DCs (DPT-DCs) enhance immune priming and regression of an established tumor in vivo. Furthermore, migration of DPT-DCs to the draining lymph nodes was induced via CCR7 upregulation. Mice that received DPT-DCs displayed enhanced antitumor therapeutic efficacy, which was associated with increased IFN-${\gamma}$ production and induction of cytotoxic T lymphocyte activity. Conclusion: These findings strongly suggest that the adjuvant effect of DPT in DC vaccination is associated with the polarization of T effector cells toward a Th1 phenotype and provides a potential therapeutic antitumor immunity.

• Clinical and Experimental Pediatrics
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• v.45 no.3
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• pp.383-389
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• 2002

We experienced a case of partial DiGeorge syndrome in a $35^{＋5}$ week premature female infant presented with micrognathia, fish-shaped mouth, beaked nose, nasal regurgitation, obstructive sleep apnea, velopharyngeal insufficiency and late onset hypocalcemic seizures. The chromosome 22q11 microdeletion was found by the FISH method. The lab findings showed serum calcium level of 4.4 mg/dL, ionized calcium level of 0.49 mg/dL, phosphorous level of 7.5 mg/dL, magnesium level of 1.3 mg/dL and PTH-RIA level of <1 pq/mL. Initial treatment was done with 10% calcium gluconate infusion and magnesium sulfate followed by oral calcium gluconate and low phosphorousformula milk feeding. The serum calcium level was normalized in 6 days. Nasal regurgitation, desaturation with obstructive sleep apnea continued. T-cell functions & numbers(CD 3, CD 4, CD 8)were decreased but Ig G/A/M levels were normal. No visible signs of thymus shadow were seen in either chest X-ray & chest MRI. Electrocardiography and echocardiography showed normal heart. Kidney ultrasonographby showed right side mild hydronephrosis. Neurosonography was normal but EEG showed electrical partial seizure. Hearing assessment by BERA showed mild to moderate hearing impairment. Velopharyngoplasty is scheduled for further treatment. A brief review of literature was made.

• Journal of Microbiology and Biotechnology
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• v.28 no.1
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• pp.122-135
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• 2018

Listeriolysin O (LLO), one of the most immunogenic proteins of Listeria monocytogenes and its main virulence factor, mediates bacterial escape from the phagosome of the infected cell. Thus, its expression in a nonpathogenic bacterial host may enable effective delivery of heterologous antigens to the host cell cytosol and lead to their processing predominantly through the cytosolic MHC class I presentation pathway. The aim of this project was to characterize the delivery of a model antigen, chicken egg ovalbumin (OVA), to the cytosol of dendritic cells by recombinant Bacillus subtilis vegetative cells expressing LLO. Our work indicated that LLO produced by non-sporulating vegetative bacteria was able to support OVA epitope presentation by MHC I molecules on the surface of antigen presenting cells and consequently influence OVA-specific cytotoxic T cell activation. Additionally, it was proven that the genetic context of the epitope sequence is of great importance, as only the native full-sequence OVA fused to the N-terminal fragment of LLO was sufficient for effective epitope delivery and activation of $CD8^+$ lymphocytes. These results demonstrate the necessity for further verification of the fusion antigen potency of enhancing the MHC I presentation, and they prove that LLO-producing B. subtilis may represent a novel and attractive candidate for a vaccine vector.

• BMB Reports
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• v.44 no.4
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• pp.273-278
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• 2011

Destruction of the skin barrier by thermal injury induces microbial invasion, which can lead to the development of systemic infection and septic shock. Microbial pathogens possess pathogen-associated molecular patterns (PAMPs), which are recognized by conserved receptors. To understand the role of PAMPs in thermal injury-induced mice, LPS or CpG-DNA were topically applied to dorsal skin after thermal injury. We observed an increase in the number of inflammatory cell infiltrates as well as thickening in the dermis upon treatment with LPS or CpG-DNA. We also found that expression of IL-$1{\beta}$, MIP-2, and RANTES induced by thermal injury was enhanced by LPS or CpG-DNA. In addition, the proportions of $CD4^+$ and $CD^8+$ T cells in the spleen and lymph nodes were altered by LPS or CpG-DNA. These results provide important information concerning PAMPs-induced inflammation upon thermal injury and provide a basis for studying the role of PAMPs in thermal injury-induced complications.

• Korean Journal of Medicinal Crop Science
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• v.26 no.1
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• pp.72-81
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• 2018

Background: Polysaccharides are the most important functional constituent in Astragalus membranaceus. The purpose of the present study was to evaluate the effect of polysaccharides isolated from the aboveground parts of A. membranaceus (AMA) and polysaccharides isolated from the roots of A. membranaceus (AMR) immune function by modulated cytotoxic T cell and Th1- and Th2-related cytokines kinetics. Methods and Results: Sprague-Dawley rats were randomly divided into exhaustive exercise case groups and non-exercise case, AMA and AMR samples were administered orally for 30 days (500 mg/kg/day and 10 mg/kg/day, respectively) and were compared to those rats in the groups fed commercial sports drink (SPD) and vehicle. Both exhaustive exercise groups and non-exercise groups had a lower ratio of $CD4^+$ and $CD8^+$ cells in the spleens of the rat fed AMA and AMR compared to those in the rats fed SPD and vehicle group. These results suggested that AMA and AMR promote an increase in the proportion of cytotoxic T cells. The IL-4-producing T lymphocytes decreased significantly in the AMR (10 mg/kg/day) group compared to SPD and vehicle, whereas the AMA group increased the IL-4 concentration more than the SPD and vehicle in exhaustive exercise group. However, the populations of IFN-${\gamma}$-producing T lymphocytes of AMR and AMA increased. AMA decreased the concentration of IFN-${\gamma}$ to inhibit the Th1 response and thereby increased the concentration of IL-4 to induce a Th2 response that was related to humoral immunity in the non-exercise group. Conclusions: These results showed that, in addition to Th1/Th2 regulation, AMR and AMA played an important immuno-modulatory role after exhaustive exercise-induced Th1/Th2 lymphocyte imbalance, which might be correlated with cytokine producing immunoregulatory cells.

• IMMUNE NETWORK
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• v.8 no.2
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• pp.39-45
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• 2008

Background: Down regulation of major histocompatibility complex class II transactivator (CIITA) has been identified as a major factor of immunosuppression in sepsis and the level of CIITA expression inversely correlates with the degree of severity. However, it has not been fully elucidated whether the lower expression of CIITA is a cause of disease process or a just associated sign. Here we determined whether the CIITA deficiency decreased survival rate using murine sepsis model. Methods: Major histocompatibility complex class II (MHC-II) deficient, CIITA deficient and wild type B6 mice were subjected to cecal ligation puncture (CLP) surgery. CIITA and recombination activation gene (RAG)-1 double deficient mice were generated to test the role of lymphocytes in CIITA-associated sepsis progression. Results: Sepsis mortality was enhanced in CIITA deficient mice, not by impaired bacterial clearance resulted from CD4 T cell depletion, but hyper-inflammatory response such as excessive release of a pro-inflammatory cytokine, high-mobility group box 1 (HMGB1). Conclusion: Our results demonstrate that CIITA deficiency affects the course of sepsis via the unexpected function of CIITA, regulation of cytokine release.

• Journal of Ginseng Research
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• v.32 no.3
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• pp.250-256
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• 2008

Red ginseng is a medicinal herb widely used in East-Asia for a long time. Recently there have been a lot of studies about the effect of red ginseng on the immune responses. We investigated the differences between Korean red ginseng and Chinese red ginseng in the lymphocyte proliferation and cytokine production. The rats were divided into 3 groups, KRG(Korean Red Ginseng) group, CRG(Chinese Red Ginseng) group, and the Control group. Experimental groups were administered with Korean and Chinese red ginsengs for three months respectively. Then we obtained the lymphatic cells from spleen and compared the ability of KRG on the lymphocyte proliferation and the cytokine production after mitogen-stimulated culture to CRG. The proliferation of lymphocyte and level of $IL-1{\alpha}$ were significantly increased only in KRG group. There were significant increases in the level of $INF-{\gamma}$ in both KRG and CRG groups. There were no significant differences in the level of IL-2 and $TNF-{\alpha}$. These results indicate that KRG can induce infection-relevant immune responses much faster and higher than CRG. Furthermore, functional activation of CD8+ T-cell may be activated by red ginsengs.

• IMMUNE NETWORK
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• v.19 no.1
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• pp.2.1-2.13
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• 2019

The enhanced differentiation and activation of osteoclasts (OCs) in the inflammatory arthritis such as rheumatoid arthritis (RA) and gout causes not only local bone erosion, but also systemic osteoporosis, leading to functional disabilities and morbidity. The induction and amplification of NFATc1, a master regulator of OC differentiation, is mainly regulated by receptor activator of NF-κB (RANK) ligand-RANK and calcium signaling which are amplified in the inflammatory milieu, as well as by inflammatory cytokines such as TNFα, IL-1β and IL-6. Moreover, the predominance of CD4⁺ T cell subsets, which varies depending on the condition of inflammatory diseases, can determine the fate of OC differentiation. Anti-citrullinated peptide antibodies which are critical in the pathogenesis of RA can bind to the citrullinated vimentin on the surface of OC precursors, and in turn promote OC differentiation and function via IL-8. In addition to adaptive immunity, the activation of innate immune system including the nucleotide oligomerization domain leucine rich repeat with a pyrin domain 3 inflammasome and TLRs can regulate OC maturation. The emerging perspectives about the diverse and close interactions between the immune cells and OCs in inflammatory milieu can have a significant impact on the future direction of drug development.

• BMB Reports
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• v.52 no.4
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• pp.289-294
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• 2019

The present study evaluated the role of AHNAK in Bartonella henselae infection. Mice were intraperitoneally inoculated with $2{\times}10^8$ colony-forming units of B. henselae Houston-1 on day 0 and subsequently on day 10. Blood and tissue samples of the mice were collected 8 days after the final B. henselae injection. B. henselae infection in the liver of Ahnak-knockout and wild-type mice was confirmed by performing polymerase chain reaction, with Bartonella adhesion A as a marker. The proportion of B. henselae-infected cells increased in the liver of the Ahnak-knockout mice. Granulomatous lesions, inflammatory cytokine levels, and liver enzyme levels were also higher in the liver of the Ahnak-knockout mice than in the liver of the wild-type mice, indicating that Ahnak deletion accelerated B. henselae infection. The proportion of CD4+interferon-${\gamma}$ ($IFN-{\gamma}^+$) and $CD4^+$ interleukin $(IL)-4^+$ cells was significantly lower in the B. henselae-infected Ahnak-knockout mice than in the B. henselae-infected wild-type mice. In vitro stimulation with B. henselae significantly increased $IFN-{\gamma}$ and IL-4 secretion in the splenocytes obtained from the B. henselae-infected wild-type mice, but did not increase $IFN-{\gamma}$ and IL-4 secretion in the splenocytes obtained from the B. henselae-infected Ahnak-KO mice. In contrast, $IL-1{\alpha}$, $IL-1{\beta}$, IL-6, IL-10, RANTES, and tumor necrosis $factor-{\alpha}$ secretion was significantly elevated in the splenocytes obtained from both B. henselae-infected wild-type and Ahnak-knockout mice. These results indicate that Ahnak deletion promotes B. henselae infection. Impaired $IFN-{\gamma}$ and IL-4 secretion in the Ahnak-knockout mice suggests the impairment of Th1 and Th2 immunity in these mice.