• Journal of Life Science
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• v.24 no.12
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• pp.1356-1363
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• 2014

Ghrelin is a 28 amino acid orexigenic peptide hormone that is secreted predominantly by tX/A cells in the stomach, and it plays a major role in energy homeostasis. Activated ghrelin has an n-octanoyl group covalently linked to the hydroxyl group of the Ser3 residue, which is critical for its binding to the G-protein coupled growth hormone secretagogue receptor-1a (GHS-R1a). According to recent reports, both ghrelin and its receptor, GHS-R1a, are expressed by a variety of immune cells, including T- and B-lymphocytes, monocytes, and dendritic cells, and ghrelin stimulation of leukocytes provides a potent immunomodulatory signal controlling systemic and age-associated inflammation and thymic involution. Here, we report that ghrelin protected murine thymocytes from dexamethasone (DEX)-induced cell death both in vivo and in vitro. Subsequently, we explored the molecular mechanisms of the antiapoptotic effect of ghrelin. According to our experiments, ghrelin inhibited the expression of proapoptotic proteins via the regulation of glucocorticoid receptor (GR) phosphorylation. As a result, ghrelin inhibited the proapoptotic activation of proteins, such as Caspase-3, PARP, and Bim. These data suggest that ghrelin, through GHS-R, inhibits the pathway to apoptosis by regulation of the proapoptotic protein activation signal pathway. They provide evidence that blocking apoptosis is an essential function of ghrelin during the development of thymocytes.

• IMMUNE NETWORK
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• v.9 no.4
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• pp.138-146
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• 2009

Background: The MHC region of the chromosome contains a lot of genes involved in immune responses. Here we have investigated the mouse NG29/Cd320 gene in the centrometrically extended MHC region of chromosome 17. Methods: We cloned the NG29 gene by RT-PCR and confirmed the tissue distribution of its gene expression by northern blot hybridization. We generated the NG29 gene expression constructs and polyclonal antibody against the NG29 protein to perform the immunofluorescence, immunoprecipitation and flow cytometric analysis. Results: The murine NG29 gene and its human homologue, the CD320/8D6 gene, were similar in the gene structure and tissue expression patterns. We cloned the NG29 gene and confirmed its expression in plasma membrane and intracellular compartments by transfecting its expresssion constructs into HEK 293T cells. The immunoprecipitation studies with rabbit polyclonal antibody raised against the NG29-NusA fusion protein indicated that NG29 protein was a glycoprotein of about 45 kDa size. A flow cytometric analysis also showed the NG29 expression on the surface of Raw 264.7 macrophage cell line. Conclusion: These findings suggested that NG29 gene in mouse extended MHC class II region was the orthologue of human CD320 gene even though human CD320/8D6 gene was located in non-MHC region, chromosome 19p13.

• BMB Reports
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• v.40 no.4
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• pp.486-493
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• 2007

Atopic dermatitis (AD) is a chronic inflammatory skin disease and the pathogenesis of AD is associated with the release of various cytokines/chemokines due to activated $Th_2$ immune responses. Synthetic oligodeoxynucleotides (ODNs) containing unmethylated CpG dinucleotide in the context of particular base sequence (CpG motifs) are known to have the immunostimulatory activities in mice and to convert from Th2 to Th1 immune responses in AD. We aimed to investigate that CpG ODN, especially phosphodiester form, can stimulate the protective immunity in NC/Nga mice with AD. We isolated BMDCs from NC/Nga mice and then, cultured with GM-CSF and IL-4 for 6 days, and treated for 2 days by either phosphorothioate ODN or phosphodiester ODN. CpG ODN-treated DCs resulted in more production of IL-12. When CpG ODN-treated DCs were intravenously injected into the NC/Nga mice, the NC/Nga mice with CpG ODN-treated DCs showed significant improvement of AD symptoms and decrease of IgE level. Histopathologically, the NC/Nga mice skin with CpG ODN-treated DCs showed the decreased IL-4 and TARC expression comparing with non-injected mice. These results may suggest that phosphodiester CpG ODN-treated DCs might function as a potent adjuvant for AD in a mouse model.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.69-70
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• 2006

In lithium-ion batteries, separator membrane's, main role is to physically isolate a cathode and an anode while maintaining rapid transport of ionic charge carriers during the passage of electric current. As far as battery safety is concerned, the electrical isolation of electrodes is most crucial since unexpected short-circuits across the membrane induces hot spots where thermal runaway may break out. Internal short-circuits are generally believed to occur by protrusions on the electrode surface either by unavoidable deposits of metallic impurities or by dendritic lithium growth during battery operation. Another cause is shrinkage of the separator membrane when exposed to heat. If separator membrane can be engineered to prevent the internal short-circuit, it will not be difficult to improve lithium-ion batteries' safety. Commonly the separators employed in lithium-ion batteries are made of polyethylene (PE) and/or polypropylene (PP). These materials have terrible limitations in preventing the fore-mentioned internal short-circuit between electrodes due to their poor dimensional stability and mechanical strength. In this study we have developed a novel separator membrane that possesses very high thermal and mechanical stability. The cells employing this separator provided noticeable safety improvement in the various abuse tests.

• IMMUNE NETWORK
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• v.6 no.4
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• pp.169-178
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• 2006

Background: Adipose tissues were initially introduced as energy storages, but recently they have become famous as an endocrine organ which produces and secretes various kinds of molecules to make physiologic and metabolic changes in human body. It has been studied that these molecules are secreted in abundance as the adipose tissue becomes bigger along with obesity. Furthermore, it has been found that they are mediating systemic inflammation and generation of metabolic diseases such as type 2 diabetes and atherosclerosis. On the basis of these, we studied previous papers which have been researched about the interaction between preadipocytes and macrophages, adipose tissues and lymph nodes, and adipose tissue secreting molecules. Results: Firstly, preadipocytes and macrophages are expressing similar transcriptomes and proteins, and preadipocytes can be converted to mature macrophages which have phagocytic activity. Moreover, the monocytes, which initially located in the bone marrow, are filtrated to the adipose tissue by monocyte chemotatic protein-1 and are matured to macrophages by colony stimulating factor-1. Secondly, adipose tissues and their associated lymph nodes are interacting each other in terms of energy efficiency. Lymph nodes promote lipolysis in adipose tissues, and polyunsaturated fatty acids in adipocytes become energy sources for dendritic cells. Lastly, adipose tissues produce and secrete proinflammatory molecules such as leptin, adiponectin, TNF-${\alpha}$, IL-6, and acute phase proteins, which induce the inflammation and potentially generate metabolic diseases. Conclusion: According to these, we can link adipose tissues to inflammation, but we need to affirm the actual levels and roles of adipose tissue-derived proinflammatory molecules in human body.

• BMB Reports
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• v.44 no.11
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• pp.758-763
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• 2011

Immunostimulatory CpG-DNA targeting TLR9 is one of the most extensively evaluated vaccine adjuvants. Previously, we found that a particular form of natural phosphodiester bond CpG-DNA (PO-ODN) encapsulated in a phosphatidyl-${\beta}$-oleoyl-${\gamma}$-palmitoyl ethanolamine (DOPE) : cholesterol hemisuccinate (CHEMS) (1 : 1 ratio) complex (Lipoplex(O)) is a potent adjuvant. Complexes containing peptide and Lipoplex(O) are extremely useful for B cell epitope screening and antibody production without carriers. Here, we showed that IL-12 production was increased in bone marrow derived dendritic cells in a CpG sequence-dependent manner when PO-ODN was encapsulated in Lipoplex(O), DOTAP or lipofectamine. However, the effects of Lipoplex(O) surpassed those of PO-ODN encapsulated in DOTAP or lipofectamine and also other various forms of liposome-encapsulated CpG-DNA in terms of potency for protein antigen-specific IgG production and Th1- associated IgG2a production. Therefore, Lipoplex(O) may have a unique potent immunoadjuvant activity which can be useful for various applications involving protein antigens as well as peptides.

• Applied Microscopy
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• v.42 no.2
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• pp.77-86
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• 2012

The morphological and histologic differentiation of the central nervous system (CNS) in the wolf spider Arctosa kwangreungensis with respect to postembryonic development are studied using light and scanning electron microscopes. The organization of CNS which consisted of supraesophageal ganglion (SpG) and subesophageal ganglion (SbG) are established prior to the postembryo stage. The brain of first instar spiderling after a molt of the postembryo is also made up of supraesophageal ganglion and subesophageal ganglion. Although development of the optic nerve and optic lobe in SpG are not completed during the postembryoic stage, completion of whole neural system resemble to that of adult are established during the second instar stage. In particular, optic gangalion is developed from the undifferentiated cell clusters of the SpG, moreover four pairs of appendage ganglia and another pairs of abdominal ganglia are produced from the SbG. Nerve cells of the most developing stages are composed of typical monopolar neur1ons, and total three types of neurons can be identified through the histological and morphological basis of present study. These cell clusters are differentiated into neurons and grow dendritic fibers according to further development of the CNS.

• YAKHAK HOEJI
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• v.47 no.3
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• pp.167-175
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• 2003

Eleutherococcus senticosus is a typical oriental folk medicinal herb. It has been used clinically as a anti-rheumatic disease, anti-stress, ischemic heart disease and gastric ulcer. In the present study, we examined the adjuvant activity of the crude polysaccharides fraction from Eleutherococcus senticosus, EN-3, on the induction of humoral and cellular immune responses against bovine serum albumin (BSA) or ovalbumin (OVA). The thioglycollate-induced macrophages and silica-induced dendritic-like cells cultured with BSA and EN-3 synergistically increased the production of TNF-$\alpha$ and IL-12. When mice were subcutaneously immunized with BSA + EN-3, the antibody titer against BSA was showed significantly higher than those immunized with BSA alone. In addition, when mice were immunized with OVA + FIA + EN-3, the antibody titer was showed similar patterns with the FCA. The assay for determining subisotype of antibody revealed that EN-3 augmented OVA-specific antibody titer of IgG1 and IgG2b. The culture supernatant obtained from splenocytes of mice treated with OVA + FIA + EN-3 also showed a higher level of both OVA-specific Th1-type (IL-2, IFN-${\gamma}$ and GM-CSF) and Th2-type cytokine (IL-4, IL-6 and IL-10). In vitro analysis of T cell proliferation to OVA on 8 weeks, the splenocytes of mice treated with OVA + EN-3 showed a significantly higher proliferating activity than those treated with OVA alone. These results suggest that EN-3 may possess adjuvant activities to potentially to enhance humoral as well as cellular immune response.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.33-40
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• 2007

We have designed and synthesized three Zn(II)-porphyrin derivatives, such as Zn(II) porphyrin ([G-0]Zn-P1) and aryl ether-typed dendron substituted Zn(II)-porphyrin derivatives ([G-1]Zn-P1 and [G-1]Zn-P-CN1). Their chemical structures were characterized by 1H-NMR, FT-IR, UV-vis absorption, EI-mass, and MALDI-TOF mass spectroscopies. Their electrochemical properties were studied by cyclic voltammetry measurement. These Zn(II)-porphyrin derivatives have been used to fabricate dye-sensitized solar cells (DSSCs) based on solid polymeric electrolytes as dye sensitizers and their device performances were evaluated by comparing with that of a standard Ru(II) complex dye. [G-1]Zn-P-CN1 showed the enhanced power conversion efficiency than those of other porphyrin derivatives, as expected. Short-circuit photocurrent density (Jsc), open-circuit voltage (Voc), fill factor (FF), and power conversion efficiency (η) of solid-typed DSSC for [G-1]Zn-P-CN1 were evaluated to be Jsc = 11.67 mA/cm2, Voc = 0.51 V, FF = 0.46, and η = 2.76%, respectively.

• Molecules and Cells
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• v.38 no.10
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• pp.876-885
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• 2015

N-acetyl-D-glucosamine kinase (NAGK) plays an enzyme activity-independent, non-canonical role in the dendritogenesis of hippocampal neurons in culture. In this study, we investigated its role in axonal development. We found NAGK was distributed throughout neurons until developmental stage 3 (axonal outgrowth), and that its axonal expression remarkably decreased during stage 4 (dendritic outgrowth) and became negligible in stage 5 (mature). Immunocytochemistry (ICC) showed colocalization of NAGK with tubulin in hippocampal neurons and with Golgi in somata, dendrites, and nascent axons. A proximity ligation assay (PLA) for NAGK and Golgi marker protein followed by ICC for tubulin or dynein light chain roadblock type 1 (DYNLRB1) in stage 3 neurons showed NAGK-Golgi complex colocalized with DYNLRB1 at the tips of microtubule (MT) fibers in axonal growth cones and in somatodendritic areas. PLAs for NAGK-dynein combined with tubulin or Golgi ICC showed similar signal patterns, indicating a three way interaction between NAGK, dynein, and Golgi in growing axons. In addition, overexpression of the NAGK gene and of kinase mutant NAGK genes increased axonal lengths, and knockdown of NAGK by small hairpin (sh) RNA reduced axonal lengths; suggesting a structural role for NAGK in axonal growth. Finally, transfection of 'DYNLRB1 (74-96)', a small peptide derived from DYNLRB1's C-terminal, which binds with NAGK, resulted in neurons with shorter axons in culture. The authors suggest a NAGK-dynein-Golgi tripartite interaction in growing axons is instrumental during early axonal development.