• Asian Pacific Journal of Cancer Prevention
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• 제16권17호
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• pp.7497-7500
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• 2015

Background: Tumor markers, designated as a broad group of substances produced by malignancies, could be in the form of biochemical substances, immunological substances, cell surface changes and genetic alterations. Cancer, a disorder of cellular behavior is characterized by alteration of serum glycoproteins. L-fucose, a hexose, which is the terminal sugar in most of the plasma glycoproteins, may be useful as a tumor marker for the detection, monitoring and prognostic assessment of malignancies. The aim of the study was to ascertain the role of serum fucose as a biomarker for early detection of oral cancer and to compare serum fucose levels in healthy controls, leukoplakia and oral cancer patients. Materials and Methods: The study included 60 (100.0%) subjects, who were grouped as 20 (33.3%) control subjects, 20 (33.3%) squamous cell carcinoma patients and 20 (33.3%) leukoplakia patients. Fucose estimation was done using UV-visible spectrophotometry based on the method as adopted by Winzler using cysteine reagent. The results were analyzed statistically using ANOVA with Bonferroni post hoc tests. Results: Results showed a high significance in serum fucose in oral squamous cell carcinoma (OSCC) and leukoplakia subjects compared to normal controls. There was a gradual increase in the values noted from control to leukoplakia and to squamous cell carcinoma. Conclusions: Estimation of serum fucose may be a reliable marker and can be used as an effective diagnostic biomarker in oral squamous cell carcinoma patients.

• Ocean and Polar Research
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• 제25권4호
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• pp.607-615
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• 2003

Many organisms are known to survive in icy environments. These include both over wintering terrestrial insects and plants as well the marine fish inhabiting high latitudes. The adaptation of these organisms is both a fascinating and important topic in biology. Marine teleosts in particular, can encounter ice-laden seawater that is approximately $1^{\circ}C$ colder than the colligative freezing point of their body fluids. These animals produce a unique group of proteins, the antifreeze proteins (AFPs) or antifreeze glycoproteins (AFGPs) that absorb the ice nuclei and prevent ice crystal growth. Presently, there are at least four different AFP types and one AFGP type that are isolated from a wide variety of fish. Despite their functional similarity, there is no apparent common protein homology or ice-binding motifs among these proteins, except that the surface-surface complementarity between the protein and ice are important for binding. The remarkable diversity of these proteins and their odd phylogenetic distribution would suggest that these proteins might have evolved recently in response to sea level glaciations just 1-2 million years ago in the northern hemisphere and 10-30 million years ago around Antarctica. Winter flounder, Pleuronectes americanus, has been used as a popular model to study the regulation of AFP gene expression. It has a built-in annual cycle of AFP expression controlled negatively by the growth hormone. The signal transduction pathways, transcription factors and promoter elements involved in this process have been studied in our laboratory and these studies will be presented.

• Journal of Microbiology and Biotechnology
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• 제18권12호
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• pp.1945-1952
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• 2008

Sialylation, the attachment of sialic acid residues to a protein, can affect the biological activity and in vivo circulatory half-life of glycoproteins. Human ${\alpha}2$,3-sialyltransferase (${\alpha}2$,3-ST) and ${\beta}1$,4-galactosyltransferase (${\beta}1$,4-GT) are responsible for terminal sialylation and galactosylation, respectively. Enhanced sialylation of human erythropoietin (EPO) by the expression of ${\alpha}2$,3-ST and ${\beta}1$,4-GT was achieved using recombinant Chinese hamster ovary (CHO) cells (EC1). The sialic acid content and sialylation of N-glycans were evaluated by HPLC. When ${\alpha}2$,3-ST was expressed in CHO cells (EC1-ST2), the sialic acid content (moles of sialic acid/mole of EPO) increased from 6.7 to 7.5. In addition, the amount of trisialylated glycans increased from 17.3% to 26.1 %. When ${\alpha}2$,3-ST and ${\beta}1$,4-GT were coexpressed in CHO cells (EC1-GTST15), the degree of sialylation was greater than that in EC1-ST2 cells. In the case of EC1-GTST15 cells, the sialic acid content increased to 8.2 and the proportion of trisialylated glycans was markedly increased from 17.3% to 35.5%. Interestingly, the amount of asialoglycans decreased only in the case of GTST15 cells (21.4% to 14.2%). These results show that coexpression of ${\alpha}2$,3-ST and ${\beta}1$,4-GT is more effective than the expression of ${\alpha}2$,3-ST alone. Coexpression of ${\alpha}2$,3-ST and ${\beta}1$,4-GT did not affect CHO cell growth and metabolism or EPO production. Thus, coexpression of ${\alpha}2$,3-ST and ${\beta}1$,4-GT may be beneficial for producing therapeutic glycoproteins with enhanced sialylation in CHO cells.

• The Korean Journal of Physiology and Pharmacology
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• 제7권3호
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• pp.143-147
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• 2003

Poly-L-lysine (PLL) was reported to suppress mucin release from airway goblet cells during 30 min treatment period. In this study, we investigated whether PLL consistently suppresses mucin release from cultured airway goblet cells during 24 h after 30 min treatment and also specifically suppresses the release of mucin without any effects on the other releasable glycoproteins. Confluent primary hamster tracheal surface epithelial (HTSE) cells were metabolically radiolabeled with $^3H$-glucosamine for 24 h and chased for 30 min in the presence of varying concentrations of PLL to assess the effects on $^3H$-mucin release and on the total elution profile of the treated culture medium. The total mucin content during 24 h after 30 min treatment of PLL was assesed to investigate the consistency of effects. PLL did not affect the release of the other releasable glycoproteins whose molecular weights were less than mucin, and decreased the total mucin content during 24 h after 30 min treatment. We conclude that PLL can specifically suppress mucin release from cultured airway goblet cells and the suppression on mucin release is consistent. This finding suggests that PLL might be used as a specific airway mucin-regulating agent by directly acting on airway mucin-secreting cells.

• Journal of Microbiology
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• 제45권1호
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• pp.41-47
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• 2007

The Hantaan virus (HTNV) is an enveloped virus that is capable of inducing low pH-dependent cell fusion. We molecularly cloned the viral glycoprotein (GP) and nucleocapsid (NP) cDNA of HTNV and expressed them in Vero E6 cells under the control of a CMV promoter. The viral gene expression was assessed using an indirect immunofluorescence assay and immunoprecipitation. The transfected Vero E6 cells expressing GPs, but not those expressing NP, fused and formed a syncytium following exposure to a low pH. Monoclonal antibodies (MAbs) against envelope GPs inhibited cell fusion, whereas MAbs against NP did not. We also investigated the N-linked glycosylation of HTNV GPs and its role in cell fusion. The envelope GPs of HTNV are modified by N-linked glycosylation at five sites: four sites on G1 (N134, N235, N347, and N399) and one site on G2 (N928). Site-directed mutagenesis was used to construct eight GP gene mutants, including five single N-glycosylation site mutants and three double-site mutants, which were then expressed in Vero E6 cells. The oligosaccharide chain on residue N928 of G2 was found to be crucial for cell fusion after exposure to a low pH. These results suggest that G2 is likely to be the fusion protein of HTNV.

• IMMUNE NETWORK
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• 제13권6호
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• pp.275-282
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• 2013

Influenza virus is one of the major sources of respiratory tract infection. Due to antigenic drift in surface glycoproteins the virus causes annual epidemics with severe morbidity and mortality. Although hemagglutinin (HA) is one of the highly variable surface glycoproteins of the influenza virus, it remains the most attractive target for vaccine development against seasonal influenza infection because antibodies generated against HA provide virus neutralization and subsequent protection against the virus infection. Combination of recombinant adenovirus (rAd) vector-based vaccine and mucosal administration is a promising regimen for safe and effective vaccination against influenza. In this study, we constructed rAd encoding the globular head region of HA from A/Puerto Rico/8/34 virus as vaccine candidate. The rAd vaccine was engineered to express high level of the protein in secreted form. Intranasal or sublingual immunization of mice with the rAd-based vaccine candidates induced significant levels of sustained HA-specific mucosal IgA and IgG. When challenged with lethal dose of homologous virus, the vaccinated mice were completely protected from the infection. The results demonstrate that intranasal or sublingual vaccination with HA-encoding rAd elicits protective immunity against infection with homologous influenza virus. This finding underlines the potential of our recombinant adenovirus-based influenza vaccine candidate for both efficacy and rapid production.

• 약학회지
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• 제57권4호
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• pp.250-257
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• 2013

Biosimilars are important drugs in medicine and contain many glycosylated proteins. Thorough analysis of the glycosylated protein is a prerequisite for evaluation of biosimilar glycan drugs. A method to assess the diversity of N-glycosylation sites and N-glycans from biosimilar glycan drugs has been developed using two separate methods, LC-MS/MS and MALDI-TOF MS, respectively. Development of sensitive, accurate, and efficient methods for evaluation of glycoproteins is still needed. In this study, analysis of both N-glycosylation sites and N-glycans of glycoprotein was performed using the same LC-MS/MS with two different nano-LC columns, nano-C18 and nano-porous graphitized carbon (nano-PGC) columns. N-glycosylated proteins, including RNAse B (one N-glycosylation site), Fetuin (three sites), and ${\alpha}$-1 acid glycoprotein (four sites), were used, and small amounts of each protein were used for identification of N-glycosylation sites. In addition, high mannose N-glycans (one type of typical glycan structure), Mannose 5 and 9, eluted from RNAse B, were successfully identified using nano-PGC-LC MS/MS analysis, and the abundance of each glycan from the glycoprotein was calculated. This study demonstrated an accurate and efficient method for determination of N-glycosylation sites and N-glycans of glycoproteins based on high sensitive LC-MS/MS using two different nano-columns; this method could be applied for evaluation of the quality of various biosimilar drugs containing N-glycosylation groups.

• Journal of Periodontal and Implant Science
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• 제27권3호
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• pp.597-602
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• 1997

Glanzmann's thrombasthenia is a Qualitative platelet disorder characterized by a deficiency in the platelet membrane glycoproteins IIb/IIIa. It belongs to a group of hereditary platelet disorders typified by normal platelet numbers and a prolonged bleeding time. The severity of bleeding does not correlate with the severity of the platelet glycoprotein IIb/IIIa a abnormality. The present case report describes the periodontal treatment of a patient with Glanzmann's thrombasthenia. A 30-year-old female with a history of Glanzmann's thrombasthenia was referred for gingival bleeding on tooth brushing and discomforts in #38 area. The periodontal finding revealed a diagnosis of localized slight adult periodontitis. Root planing and extraction of #38 was performed under 12 pack of platelets transfusion and digital compression was done for hemostasis. The gingival bleeding ceased within a day in maxilla and 2 days later in mandible. 42 pack of platelets was administered for 3 days of post-treatment and for iron-deficiency anemia 3 pack of RBCs was transfused 2 days later. 1 week later the inflammation in gingiva disappeared and gingival stippling appeared. The clinical result we got was good and in such a medically compromised patient it is an ability to maintain a proper oral hygiene that is essential both for oral and systemic health.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2016년도 춘계학술대회 및 임시총회
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• pp.41-41
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• 2016

Influenza viruses are RNA viruses that belong to the Orthomyxoviridae family, and those can be divided into three types; A, B, and C, which based on the differences of the inner nucleoproteins and genomic structures. All three genera differ in their genomic structure and nucleoprotein content, they are further classified into various serotypes based on the two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). These glycoproteins play crucial roles in viral infection and replication. Hemagglutinin mediates binding of virions to sialic acid receptors on the surfaces of target cells at the initial stage of infection. Neuraminidase cleaves the glycosidic bonds of sialic acids from the viral and cell surfaces to release the mature virions from infected cells, after viral replication. Because NA plays an important role in the viral life cycle, it is considered an attractive therapeutic target for the treatment of influenza. The methanolic extracts of Phellinus baumii and Phellinus igniarius exhibited significant activity in the neuraminidase inhibition assay. Polyphenolic compounds were isolated from the methanolic extracts. The structures of these compounds were determined to be hispidin, hypholomine B, inoscavin A, davallialactone, phelligridin D, phelligridin E, and phelligridin G by spectroscopic methods. Compounds inhibited the H1N1 neuraminidase activity in a dose-dependent manner with $IC_{50}$ values of 50.9, 22.9, 20.0, 14.2, 8.8, 8.1 and $8.0{\mu}M$, respectively. Moreover, these compounds showed anti-influenza activity in the viral cytopathic effect (CPE) reduction assay using MDCK cells. These results suggests that the polyphenols from P. baumii and P. igniarius are promising candidates for prevention and therapeutic strategies against viral infection.

• 한국동물학회지
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• 제33권2호
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• pp.191-199
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• 1990

토끼의 골격근에서 근소포체를 순수 분리하여 SDS-polyacrylamide gel전기영동법과 125 I-concanavalin A표지법으로 단백질과 당단백질의 조성을 조사하였다. 전기영동사에 나타난 대표적인 단백질은 $Ca^2$+-AThase, 80 Kd protein,calsequestrin,high affinity calcium binding protein, intrinsic glycoprotein이었으며, 160 Kd protein, 94 Kd protein,38 Kd protein, 34 Kd protein,24 Kd proteins도 존재하였다.특히, 막성계에 있는 heak protein으로 알려져 있는 80 Kd protein은 본 연구를 통해 주로 근소포체의 terminal cisternae에 들어 있음이 확인되었다. 한편 125 I-concanavalin A표지에 의해 전기영동성에 나타난 대표적인 당단백질은 160 Kd glycoprotein, 94 Kd glycoprotein, calsequestrin, intrinsic glycoprotein의 4종이었다. 이 가운데 94 Kd glycoprotein은 94 Kd glucose-regulated protein으로 추정되며, 본 연구를 통해 근소포체에서도 특히 T-tubule에 다량으로 존재함이 밝혀졌다.