• 대한세포병리학회지
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• 제8권1호
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• pp.93-97
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• 1997

A case of cervical chordoma diagnosed by fine needle aspiration is discussed. A 41year-old male was admitted due to dyspnea on neck flexion. Radiologic image revealed a retrotracheal superior mediastinal solid mass. Aspiration cytology showed many clusters of oval or large polygonal cells having abundant eosinophilic or bubbly cytoplasm in an amorphous blue-gray mucoid background. The nuclei were round and showed size variation, coarse granular chromatin, and indistinct nucleoli. Some cells contained brown granular pigments in the cytoplasm. Mitoses were rarely found. The cytoplasm was strongly positive for PAS stain. Immunohistochemical stains using cell block revealed positive reaction for cytokerain, EMA, vimentin, and S-100 protein. The confirmative diagnosis was made by following excisional biopsy. Electron microscopic study revealed large pools of intracytoplasmic glycogen and microfilaments. This is the first case of cervical chordoma diagnosed by aspiration cytology to our knowledge in Korean literature.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVI)
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• pp.420-422
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• 2005

TMC (Tautomycetin) is a liner polyketide immunosuppressive antifungal compound produced by Streptomyces spp. Inhibition of T cell proliferation with TMC was observed highly efficient at 100-fold lower than those needed to achieve maximal inhibition with cyclosporin A. To elucidate the biosynthetic pathway of TMC, a genomic DNA library was constructed using a E. coil-Streptomyces shuttle cosmid vector, pOJ446. The DNA libraries were screened by colony blot hybridization using several polyketide ${\beta}-ketosynthase$ (KS) probes amplified from TMC-producing Streptomyces genomic DNA using polymerase chain reaction (PCR), of which the degenerate primers were designed based on the highly conserved sequences present in KS domains of various type I polyketide synthase genes in Streptomyces species. This library construction and screening approach led to the isolation of several positive cosmid clones representing type I polyketide biosynthetic gene clusters. In addition, a Streptomyces regulatory gene called afsR2 (a global regulatory gene stimulating antibiotic production in both S. coelicolor and S. lividans) was successfully integrated into the TMC-producing Streptomyces chromosome via E. coil-Streptomyces heterologous conjugation mehtod. The more detailed results of production improvement and genetic characterization of TMC-producing Streptomyces spp. will be discussed.

• 대한세포병리학회지
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• 제15권1호
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• pp.70-73
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• 2004

The incidence of endometriosis in post-operative abdominal scars is rare. We describe two cases of abdominal endometriosis diagnosed by fine needle aspiration (FNA). Both patients presented with subcutaneous masses at previous cesarean section scars with cyclic symptoms of pain. The cytologic smears were cellular and comprised two distinct cell populations consisting of epithelial and stromal components. An epithelial component consisted of flat sheets of polygonal cells and the second stromal component showed crowded clusters of spindle cells or isolated single cells. Hemosiderin-laden macrophages were found in the background. FNA offers a safe and effective tool for diagnosis of abdominal wall endometriosis.

• 대한세포병리학회지
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• 제9권2호
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• pp.207-211
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• 1998

Adenoid cystic carcinoma of the uterine cervix is a rare tumor accounting for less than 1% of all cervical adenocarcinoma. This tumor is characterized by aggressive biological behavior with frequent local recurrence or metastatic spread, postmenopausal onset, and occasional association with conventional squamous cell carcinoma. The cytologic diagnosis of adenoid cystic carcinoma in the uterine cervix is often difficult because of negative smear due to intact overlying mucosa, cytologic findings mimicking endometrial cells, and masquerade as squamous ceil carcinoma. Recently we have experienced a case of adenoid cystic carcinoma arising in the uterine cervix, which was identified on the routine Papanicolaou smear and was histologically confirmed by the consequent biopsy. The smear showed abundant cellularity composed of relatively uniform cells. The tumor cells were arranged in small clusters, acini, naked cells, and loose sheets with abortive cribriform pattern. There were scattered globoid basement membrane-like materials and tumor diathesis. The nuclei were pleomorphic and showed hyperchromatic and coarsely granular choromatin with inconspicuous nucleoli. The punch biopsy of the uterine cervix showed typical histologic findings of adenoid cystic carcinoma characterized by tumor nests composed of hyperchromatic uniform basaloid cells, cribriform pattern, and cylindrical hyaline bodies.

• 대한세포병리학회지
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• 제9권2호
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• pp.221-225
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• 1998

Malignant tumors of the breast with stromal multinucleated giant cells are rare entity of uncertain clinical significance. There have been few reports on the fine needle aspiration cytologic(FNAC) findings about these rare tumors. We report a FNAC case of invasive mammary carcinoma with osteoclast-like giant cells not only for its rare occurrence but in particular for its distinctive cytologic picture on aspirated material. The patient was a 40-year-old woman who presented with a right breast mass for one month. Mammography showed a well-demarcated rounded mass density without calcification. The aspirates of FNAC were highly cellular and two main cell types were seen; malignant epithelial cells and osteoclast-like multinucleated giant cells. The carcinoma cells occurred singly or arranged in loose clusters with ill-defined cytoplasm, oval nuclei, coarse chromatin and small but distinct nucleoli. The multinucleated giant cells showed variable number of nuclei with prominent nucleoli and abundant dense oxyphilic cytoplasm. The immunocytochemical studies suggested that osteoclast-like giant cells were not of epithelial origin, but rather of histlocytic origin.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2005년도 International Meeting of the Microbiological Society of Korea
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• pp.143-147
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• 2005

The non-pathogenic, non-glycopeptide-producing actinomycete Streptomyces coelicolor carries a cluster of seven genes (vanSRJKHAX) that confers inducible, high-level resistance to vancomycin. The van genes are organised into four transcription units, vanRS, vanJ, vanK and vanHAX, and these transcripts are induced by vancomycin in a vanR-dependent manner. vanHAX are orthologuous to genes found in vancomycin resistant enterococci that encode enzymes predicted to reprogramme peptidoglycan biosynthesis such that cell wall precursors terminate in D-Ala-D-Lac, rather than D-Ala-D-Ala. vanR and vanS encode a two-component signal transduction system that mediates transcriptional induction of the seven van genes. vanJ and vanK are novel genes that have no counterpart in previously characterised vancomycin-resistance clusters from pathogens. VanK is essential for vancomycin resistance in S. coelicolor and it is required for adding Gly branch to stem peptides terminating D-Ala-D-Lac. Because VanK can recognise D-Lac-containing precursors but the constitutively expressed femX enzyme, encoded elsewhere on the chromosome, cannot recognize D-Lac-containing precursors as a substrate, vancomycin-induced expression of VanHAX in a vanK mutant is lethal. Further, femX null mutants are viable in the presence of glycopeptide antibiotics but die in their absence. Bioassay using vanJp-neo fusion reporter system also showed that all identified inducers for van genes expression were glycopeptide antibiotics, but teicoplanin, a membrane-anchored glycopeptide, failed to act as an inducer.

• 대한세포병리학회지
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• 제8권2호
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• pp.160-163
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• 1997

The cytologic finding of proliferating trichilemmal tumor is not well documented and have difficulties in the cytological analysis of the fine needle aspirates. This rare dermatopathologic entity may be encountered during aspiration biopsy of subcutaneous masses, and is, occasionally, confused with other neoplasm, particulary squamous carcinoma owing to its close cytological resemblance. We report a case of proliferating trichilemmal tumor in the left breast. The patient is a woman and had a lump in the breast for 20 years. Fine needle aspiration revealed a few small clusters of squamoid cells in the background of amorphous and calcified material. After excisional biopsy, the mass was confirmed as proliferating trichilemmal tumor. The main cytologic features discriminating squamous cell carcinoma were bland nature of epithelial cells, absence of atypical dyskeratotic cells, and rich amount of amorphous material.

• The Korean Journal of Physiology and Pharmacology
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• 제14권3호
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• pp.133-137
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• 2010

Ginsan is an acidic polysaccharide purified from Panax ginseng, a famous oriental herb. Although a variety of biological activities of ginsan have been studied, the effects of ginsan on spleen cells are not fully elucidated. We investigated the effect of ginsan on the viability and proliferation of spleen cells. Using Cell Counting $Kit-8^{(R)}$ solution and trypan blue solution, we found that ginsan significantly enhanced viability and proliferation. Multiple clusters, indicating proliferation, were observed in ginsan-treated spleen cells and, carboxyfluorescein succinimidyl ester and surface marker staining assay revealed that ginsan promoted proliferation from $CD19^+$ B cells rather than $CD4^+$ or $CD8^+$ T cells. In addition, ginsan decreased the percentage of late apoptotic cells. Ginsan increased the surface expression of CD25 and CD69 as well as production of interleukin-2 from spleen cells, suggesting increased activation. Taken together, these results demonstrate that ginsan increases the viability and proliferation of spleen cells via multiple mechanisms, valuable information for broadening the use of ginsan in clinical and research settings.

• 한국세라믹학회지
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• 제56권2호
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• pp.130-145
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• 2019

Widespread commercialization of solid oxide fuel cells (SOFCs) is expected to be realized in various application fields with the advent of cost-effective fabrication of cells and stacks in high volumes. Cost-reduction efforts have focused on production yield, power density, operation temperature, and continuous manufacturing. In this article, we examine several issues associated with processing for SOFCs from the standpoint of the bimodal packing model, considering the external constraints imposed by rigid substrates. Optimum compositions of composite cathode materials with high volume fractions of the second phase (particles dispersed in matrix) have been analyzed using the bimodal packing model. Constrained sintering of thin electrolyte layers is also discussed in terms of bimodal packing, with emphasis on the clustering of dispersed particles during anisotropic shrinkage. Finally, the structural transition of dispersed particle clusters during constrained sintering has been correlated with the structural stability of thin-film electrolyte layers deposited on porous solid substrates.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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• pp.687-690
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• 2004

Fabrication and characterization of dye-sensitized TiO2 solar cells(DSSC) consisting of spray-coated TiO2 electrode, an electrolyte containing I-/I3- redox couple, and a Pt-coated counter electrode carried out, using mainly FE-SEM and solar simulator. Also, effect of rapid thermal annealing(RTA) temperatue on I-V curves of DSSCS consisting of approximately 10m thickness and $5{\times}5mm2$ active area. No significant difference in the apparent size of TiO2 clusters was observed with increasing RTA temperature. Also, an open circuit voltage(Voc) of approximately 0.70V and a short-circuit photocurrent(Jsc) of 8 to 12mA/cm2 were observed in the TiO2 solar cell. With increasing RTA temperature upto 550oC, photocurrent density of dye-sensitized solar cells was enhanced, leading to enhancing the efficiency of dye-sensitized solar cells having Pt-electroplated counter electrode.