• BMB Reports
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• v.41 no.2
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• pp.164-169
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• 2008

The tumor suppressor gene p53 regulates apoptotic cell death and the cell cycle. In this study, we investigated the role of p53 in nitric oxide (NO)-induced apoptosis in vascular smooth muscle cells (VSMCs). We found that the NO donor S-nitroso-N-acetyl-penicillamine (SNAP) increased apoptotic cell death in p53-deficient VSMCs compared with wild-type cells. The heme oxygen-ase (HO) inhibitor tin protoporphyrin IX reduced the resistance of wild-type VSMCs to SNAP-induced cell death. SNAP promoted HO-1 expression in both cell types. HO-2 protein was increased only in wild-type VSMCs following SNAP treatment; however, similar levels of HO-2 mRNA were detected in both cell types. SNAP significantly increased the levels of non-heme-iron and dinitrosyl iron-sulfur clusters in wild-type VSMCs compared with p53-deficient VSMCs. Moreover, pretreatment with FeSO4 and the carbon monoxide donor CORM-2, but not biliverdin, significantly protected p53-deficient cells from SNAP-induced cell death compared with normal cells. These results suggest that wild-type VSMCs are more resistant to NO-mediated apoptosis than p53-deficient VSMCs through p53-dependent up-regulation of HO-2.

• The Korean Journal of Cytopathology
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• v.3 no.2
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• pp.52-59
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• 1992

A number of studies have shown the value of fine needle aspiration cytology for the diagnosis of breast lesions, but reports on the comparison of cytologic and histologic variations of breast cancers are few. We reviewed histologically proven 106 breast aspirates with an emphasis on the cytology of ductal carcinomas and of an area of uncertain atypia. Positive and negative predictive values of breast aspiration cytology were 100% On review of the cases originally diagnosed as atypia of uncertain nature (19 %), features more suggestive of malignancy or benignancy were recognizable in most underdiagnosed cases and a half of overdiagnosed cases, respectively. However, indistinguishable atypism also remained. Thirty seven cases out of 53 infiltrating duct carcinomas revealed malignant cytology, with variations in background, cellularity, morphology of cell groups, and extent of isolated tumor cells. When classifying the infiltrating duct carcinomas into scirrhous, solid-tubular, and papillotubular types, scirrhous type frequently appeared as irregularly shaped tight or loose cell clusters, and solid-tubular type as round-margined cell balls.

• The Korean Journal of Cytopathology
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• v.12 no.1
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• pp.45-48
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• 2001

Acinic cell carcinoma(ACC) is the third common malignancy in major salivary gland. Fine needle aspiration cytology is a useful tool for the diagnosis of salivary gland lesions. However, some low grade malignancies, such as ACC and mucoepidermoid carcinoma show relatively high false negative rate, mainly due to deceptively benign cytomorphologic appearance. We experienced a papillary-cystic variant of ACC, having different cytopathologic features compared with those of classic ACC. Our case showed monolayered sheets and papillary clusters without any acinic structures or naked nuclei of the tumor cells. Foamy proteinaceous material was seen in the background. The tumor cells had a large amount of granular cytoplasm and eccentric nuclei. Many vacuolated or clear cells were also noted.

• The Korean Journal of Cytopathology
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• v.14 no.1
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• pp.36-41
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• 2003

Epithelioid hemangioendothelioma is a rare vascular tumor of borderline malignancy which is characterized by the presence of "epithelioid" or "histiocytoid" endothelial cells. Superficial and deep tumors have been recognized in the extremities, head, neck, chest, and mediastinum of adult patients. It may also occur as a primary tumor of liver, bone, and other visceral organs. Few effusion cytologic findings of epithelioid hemangioendothelioma have been reported. We report a case of composite epithelioid hemangioendothelioma with focal epithelioid angiosarcomatous areas of the iliac bone and adjacent soft tissue in a 38-year-old female, which, during its metastatic course, was presented as a pleural effusion. The effusion was cellular with epithelioid cells presenting both singly and in clusters. The tumor cells were round to ovoid shewing cytoplasmic vacuolization, variability in cell size, and prominent nucleoli. The effusion smears and cell block sections revealed strong positive staining for CD31 and vimentin, weak positive for CD34 and Factor VIII-related antigen, and negative for cytokeratin, CEA, and calretinin. The cytologic findings in this case were similar to that of metastatic adenocarcinoma or malignant mesothelioma. Therefore, immunocytochemical staining in smear and cell block is a helpful tool to differentiate malignant 'epithelioid' cells in effusion.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.5
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• pp.1291-1300
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• 2004

Baicalin, a biologically active flavonoid form the roots of Scutallaria baicalensis (Skullcap), have been reported to not only function as anti-oxidants but also cause anticancer effect. We investigated the mechanism of baicalin-induced cytotoxicity and the macro scale gene expression analysis in leukemia cell line, HL-60 cells. Baicalin (10 μM) were used to treat the cells for 6h, 12h, 24h, 48h and 72h. In a human cDNAchip study of 65,000 genes evaluated 6, 12, 24, 48. 72 hours after treated with Baicalin in HL-60 cells. Hierarchical cluster against the genes which showed expression changes by more than two fold. One hundred one genes were grouped into 6 clusters according to their profile of expression by a hierarchical clustering algorithm. For genes differentially expressed in response to baicalin treatment, we tested functional classes based on Gene Ontology (GO) terms. This study provides the most comprehensive available survey of gene expression changes in response to baicalin treatment in HL-60 cell line.

• Biomolecules & Therapeutics
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• v.24 no.5
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• pp.475-481
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• 2016

PICK1, a PDZ domain-containing protein, is known to increase the reuptake activities of dopamine transporters by increasing their expressions on the cell surface. Here, we report a direct and functional interaction between PICK1 and dopamine $D_3$ receptors ($D_3R$), which act as autoreceptors to negatively regulate dopaminergic neurons. PICK1 colocalized with both dopamine $D_2$ receptor ($D_2R$) and $D_3R$ in clusters but exerted different functional influences on them. The cell surface expression, agonist affinity, endocytosis, and signaling of $D_2R$ were unaffected by the coexpression of PICK1. On the other hand, the surface expression and tolerance of $D_3R$ were inhibited by the coexpression of PICK1. These findings show that PICK1 exerts multiple effects on $D_3R$ functions.

• Journal of Energy Engineering
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• v.1 no.1
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• pp.58-65
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• 1992

Pt loaded porous carbon Pt/C electrode was prepared by hot pressing process to enhance the electrode performance in PAFC (phosphoric acid fuel cell). By changing the hot pressing conditions and PTFE contents, Pt/C electrodes were prepared and the electrochemical characteristics of oxygen reduction and unit-cell performance were evaluated. The optimum condition of hot press to make electrode is 360$^{\circ}C$ and 10 kg/$\textrm{cm}^2$. Maximum performance was obtained at 30 wt% PTFE content in the catalyst layer with 80% utilization of platinum clusters. Unit-cell performance of hot pressed Pt/C electrode was 200 mA/$\textrm{cm}^2$ at 700 ㎷ and stable performance was maintained more than 200 hr.

• The Korean Journal of Cytopathology
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• v.5 no.2
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• pp.130-136
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• 1994

Urinary cytology is increasingly accepted as a diagnostic tool in the detection and follow-up of patients with bladder cancer. However, its value is reduced by several limitations, especially by the lack of cytologic criteria specifically reflecting the morphology of low-grade urothelial neoplasm. We reviewed histologically proven 50 cases of urine cytology with emphasis on cytologic findings of benign atypia and differential findings of urothelial neoplasm according to the grade. The diagnoses included 17 benign lesions(including 5 cases of urine calculi) and 33 malignant lesions (including 28 transitional cell carcinomas, 3 squamous cell carcinomas, 1 adenocarcinoma and 1 prostate adenocarcinoma), Diagnostic accuracy was 92%. Important cytodiagnostic criteria for benign atypia and low grade malignancy were cellularity, number of cell clusters, and morphology and arrangement of urothelial cells. The cytologic findings of urothelial neoplasms according to histologic grade were relatively well correlated with the histologic findings. However, the cytologic criteria were not sufficient to readily distinguish grade I from grade II. In view of this, we think that cytologic nomenclature "low-grade" and "high-grade" is a more reliable criterion. Recognition of subtle cellular morphologic features specific for urothelial lesions(including benign or malignancy) and proper fixation, processing and staining of specimen can expand the role of urinary cytology In detection and follow-up of patients.

• Molecular & Cellular Toxicology
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• v.4 no.3
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• pp.183-191
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• 2008

Volatile organic compounds (VOCs) are common constituents of cleaning and degreasing agents, paints, pesticides, personal care products, gasoline and solvents. And VOCs are evaporated at room temperature and most of them exhibit acute and chronic toxicity to human. Benzene is the most widely used prototypical VOC and the toxic mechanisms of them are still unclear. The multi-step process of toxic mechanism can be more fully understood by characterizing gene expression changes induced in cells by toxicants. In this study, DNA microarray was used to monitor the expression levels of genes in HepG2 cells and HL-60 cells exposed to the benzene on IC20 and IC50 dose respectively. In the clustering analysis of gene expression profiles, although clusters of HepG2 and HL-60 cells by benzene were divided differently, expression pattern of many genes observed similarly. We identified 916 up-regulated genes and 1,144 down-regulated genes in HepG2 cells and also 1,002 up-regulated genes and 919 down-regulated genes in HL-60 cells. The gene ontology analysis on genes expressed by benzene in HepG2 and HL-60 cells, respectively, was performed. Thus, we found some principal pathways, such as, focal adhesion, gap junction and signaling pathway in HepG2 cells and toll-like receptor signaling pathway, MAPK signaling pathway, p53 signaling pathway and neuroactive ligand-receptor interaction in HL-60 cells. And we also found 16 up-regulated and 14 down-regulated commonly expressed total 30 genes that belong in the same biological process like inflammatory response, cell cycle arrest, cell migration, transmission of nerve impulse and cell motility in two cell lines. In conclusion, we suggest that this study is meaningful because these genes regarded as strong potential biomarkers of benzene independent of cell type.

• The Korean Journal of Cytopathology
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• v.15 no.2
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• pp.126-130
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• 2004

Granular cell tumor is characterized by large eosinophilic cells with granular appearances. These are mostly benign. Approximately $1\sim2%$ are malignant, and establishment of reliable criteria for diagnosing malignant granular cell tumor has been difficult to establish because oi the rarify. Reports on the cytologic features of this neoplasm are hardly found in Korea. We report a case of rarely-occurring granular cell tumor in the lower leg of a 40-year-old male, diagnosed on fine needle aspiration cytology, together with a review of the literature regarding significant adverse histology and prognostic factors. The aspirates revealed cellular smears of isolated cells, syncytial clusters, and occasionally stripped nuclei in a nine, bluish-purple, granular background. Tumor cells were polygonal, rounded, or slightly spindled, and showed ill-defined granular cytoplasm. Nuclei were small and round or oval, with inconspicuous or small, prominent nucleoli. The nuclei showed rare intranuclear cytoplasmic invagination. Occasionally, there were mild to moderate nuclear pleomorphisms with vesicular nuclei, with large, prominent nucleoi, but no mitosis. The immunocytochemical stain for S-100 was strongly positive in the cytoplasm of tumor cells with occasional nuclei.