• The Korean Journal of Cytopathology
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• v.4 no.1
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• pp.35-40
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• 1993

We describe a case of fine needle aspiration cytology of metastatic nasopharyngeal carcinoma in the lymph node of the neck presenting a predominantly spindle cell pattern. A 36 year-old male patient complained of dysesthesia on the right face and a palpable neck mass. Fine needle aspiration was done on the neck mass. Tumor cells were present in syncytial groups or singly with mainly spindle shaped nuclei, vesicular chromatin, thin and regular nuclear membrane, occasional prominent nucleoli and a few fool of cellular cohesiveness. The cytoplasm was scant and pale with ill-defined borders. Mature lymphocytes were present in the background of aspirates and within the tumor cell clusters. Histologically, the tumor of nasopharynx showed several areas of spindle cell pattern. Because the tumor cells showed a predominantly spindle shape with vesicular nuclear chromatin, the differential diagnosis of spindle cell sarcoma or granuloma of epithelioid clils were considered, but the characteristic morphology of the nuclei with vesicular chromatin and prominent nucleoli, and cellular cohesiveness were important in making the diagnosis of nasopharyngeal carcinoma. The possibility of metastatic carcinoma should always be considered in fine needle aspiration cytology of the lymph node in the neck because the incidence of metastatic carcinoma, particularly of the nasopharyngeal carcinoma in the lymph nodes of the neck is relatively high.

• Clinical and Experimental Reproductive Medicine
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• v.24 no.3
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• pp.301-309
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• 1997

The objective of this study was to determine the microtubule assembly and chromatin configuration during the first cell cycle in bovine oocytes following injection of spermatozoon, sperm head and tail. The microtubule and chromatin configuration was imaged with fluorescent labeled monoclonal ${\alpha}$-tubulin antibody and propidium iodide under laser scanning confocal microscope. Microtubule and chromatin dynamics in bovine oocytes following intracytoplasmic sperm injection (ICSI) were not different from those observed during in vitro fertilization (IVF). Following ICSI, the microtubular aster was observed around sperm midpiece. During pronuclear formation, the sperm aster was enlarged and seen around male and female pronuclei. At mitotic metaphase, the microtubular spindle assemble astral poles and chromosomes were aligned on the spindle equator. At mitosis, asters were concentrated to each spindle pole and they filled the cytoplasm. After injection of the isolated sperm head, the microtubular aster was not seen around sperm head in any cases (0/18). Instead, microtubules were organized from the cytoplasm, which filled the whole cytoplasm during pronuclear apposition. These microtubules seem to move male and female pronuclei. These results suggest that isolated sperm head can develop into normal pronucleus in mature bovine oocytes, and competent to participate syngamy with the ootid chromatin. The functional microtubules following isolated sperm head injection in bovine oocytes appeared to be organized solely from maternal stores.

• The Microorganisms and Industry
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• v.18 no.2
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• pp.7-12
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• 1992

• BMB Reports
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• v.40 no.2
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• pp.135-141
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• 2007

Conjugation of the methyl group at the fifth carbon of cytosines within the palindromic dinucleotide 5'-CpG-3' sequence (DNA methylation) is the best studied epigenetic mechanism, which acts together with other epigenetic entities: histone modification, chromatin remodeling and microRNAs to shape the chromatin structure of DNA according to its functional state. The cancer genome is frequently characterized by hypermethylation of specific genes concurrently with an overall decrease in the level of 5-methyl cytosine, the pathological implication of which to the cancerous state has been well established. While the latest genome-wide technologies have been applied to classify and interpret the epigenetic layer of gene regulation in the physiological and disease states, the epigenetic testing has also been seriously explored in clinical practice for early detection, refining tumor staging and predicting disease recurrence. This critique reviews the latest research findings on the use of DNA methylation in cancer diagnosis, prognosis and staging/classification.

• The Korean Journal of Cytopathology
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• v.12 no.1
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• pp.31-37
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• 2001

Whlie cytologic characteristics of squamous dysplasia, carcinoma in situ, and invasive squamous cell carcinoma of the uterine cervix are well documented, relatively few studios have dealt with the cellular features of microinvasive carcinoma. In order to describe the cellular characteristics of microinvasive squamous cell carcinoma, we retrospectively reviewed 45 cervovaginal smears(15 carcinoma in situ, 15 microinvasive cancer, 15 invasive cancer) which were confirmed by histologic examination of specimens obtained by hysterectomy at the Seoul National University Hospital during S years from 1995 to 1999. The cytologic features about tumor diathesis, inflammatory background, ceil arrangement, anisonucleosis, nuclear membrane irregularity, nuclear chromatin pattern, and nucleoli were observed. The cytologlc characteristics of microinvasive squamous cell carcinoma of the uterine cervix are syncytial pattern, mild tumor diathesis, the irregularity of nuclear membrane, irregularly distributed nuclear chromatin, and occurrence of micronucleoli. But, correlation between the depth of Invasion and the cytologic feature had limited value.

• Biomolecules & Therapeutics
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• v.11 no.2
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• pp.151-156
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• 2003

Cornis fructus have various biological effects and major chemical components have been tannins, saponins, ursolic acids, gallic acids, linoleic acids, morronisides, cornins and loganins. The main aim of the present study is measurment the effect of chloroform extract from Cornis fructus on proliferation inhibition and Cell death. Cells were cultured in the presence of chloroform extracts from Cornis fructus for 48 h. after 48h treatment of B16/F10 melanoma cells with chloroform extracts, the cells were observed a dose-dependent inhibitions of cell viability with cell death in their proliferation. the cells were estimated cell viability, cell number, total DNA fragmentation and chromatin condensation in a dose-dependent manner. It also caused cell death as measured by cell morphology, DNA fragmentation and nucleus chromatin condensation. therefore, these results suggest that chloroform extracts from C. fructus is inhibitory proliferation and is related to cell death in this cells.

• Genomics & Informatics
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• v.11 no.1
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• pp.7-14
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• 2013

As the International Human Epigenome Consortium (IHEC) launched officially at the 2010 Washington meeting, a giant step toward the conquest of unexplored regions of the human genome has begun. IHEC aims at the production of 1,000 reference epigenomes to the international scientific community for next 7-10 years. Seven member institutions, including South Korea, Korea National Institute of Health (KNIH), will produce 25-200 reference epigenomes individually, and the produced data will be publically available by using a data center. Epigenome data will cover from whole genome bisulfite sequencing, histone modification, and chromatin access information to miRNA-seq. The final goal of IHEC is the production of reference maps of human epigenomes for key cellular status relevant to health and disease.

• Korean Journal of Biological Psychiatry
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• v.15 no.4
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• pp.243-253
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• 2008

In the post-genomic era, the mechanisms controlling activation of genes are thought to be more important. Gene-environment interactions are crucial in both development and treatment of psychiatric disorders as they are complex genetic disorders. Epigenetics is defined as a change of gene expression that occurs without a change of DNA sequence and can be heritable by certain mechanisms. Epigenetic changes play essential roles in control of gene activation. DNA methylation, chromatin remodeling and RNAi act as key mechanisms for epigenetic modifications of genes. Here, we review the basic mechanisms of epigenetics and discuss their potential involvement of human diseases, including psychiatric disorders.

• BMB Reports
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• v.50 no.9
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• pp.445-453
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• 2017

CTCF, Zinc-finger protein, has been identified as a multifunctional transcription factor that regulates gene expression through various mechanisms, including recruitment of other co-activators and binding to promoter regions of target genes. Furthermore, it has been proposed to be an insulator protein that contributes to the establishment of functional three-dimensional chromatin structures. It can disrupt transcription through blocking the connection between an enhancer and a promoter. Previous studies revealed that the onset of various diseases, including breast cancer, could be attributed to the aberrant expression of CTCF itself or one or more of its target genes. In this review, we will describe molecular dysfunction involving CTCF that induces tumorigenesis and summarize the functional roles of CTCF in breast cancer.

• Molecules and Cells
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• v.37 no.12
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• pp.841-850
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• 2014

Polycomb group (PcG) proteins are conserved chromatin regulators involved in the control of key developmental programs in eukaryotes. They collectively provide the transcriptional memory unique to each cell identity by maintaining transcriptional states of developmental genes. PcG proteins form multi-protein complexes, known as Polycomb repressive complex 1 (PRC1) and Polycomb repressive complex 2 (PRC2). PRC1 and PRC2 contribute to the stable gene silencing in part through catalyzing covalent histone modifications. Components of PRC1 and PRC2 are well conserved from plants to animals. PcG-mediated gene silencing has been extensively investigated in efforts to understand molecular mechanisms underlying developmental programs in eukaryotes. Here, we describe our current knowledge on PcG-mediated gene repression which dictates developmental programs by dynamic layers of regulatory activities, with an emphasis given to the model plant Arabidopsis thaliana.