• Maxillofacial Plastic and Reconstructive Surgery
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• v.35 no.1
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• pp.1-12
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• 2013

Purpose: Vascular endothelial growth factor (VEGF)-C and its tyrosine kinase receptor, VEGF receptor (VEGFR)-3 are recently known to have lymphangiogenic activities in various tumor types. In this study, we determined whether the expression of lymphangiogenic factors correlate with nodal metastasis or survival in a nude mouse model of oral squamous cell carcinoma (OSCC). Methods: Three OSCC cells (KB, SCC4, SCC9) were xenografted into the right mandibular gland of athymic nude mice. The mice were followed for tumor development and growth, and the mice were sacrificed when they had lost more than 20% of their initial body weight, or the diameter of the induced tumor exceeds 20 mm. After necropsy, the murine tumors were examined histologically and radiologically (micro-positron emission tomography computed tomography) for regional or distant metastasis. We performed immunohistochemical assays with anti-VEGF-C, VEGFR-3, CD105, and D2-40 antibodies. Immunofluorescence double staining for LYVE-1/CD31 was also performed. To quantify the VEGF-C and VEGFR-3 level in the cancer tissue, Western blotting was performed. Finally, we determined the correlation between the degree of expression of VEGF-C/VEGFR-3 and the mean survival time. Results: OSCC tumor cells into the mandibular gland of the nude mice successfully resulted in the formation of recapitulating orthotopic tumor. Tumor cells of the induced tumor did not express VEGF-C. VEGF-C/VEGFR-3 expression was mainly distributed in the endothelial cells of the stromal area. There were no correlation between the degree of expression of VEGF-C/VEGFR-3 and the mean survival time of mice injected with different OSCC cell lines. Conclusion: An recapitulating orthotopic model of OSCC in nude mice was established, which copies the cervical nodal metastasis of human OSCC. Overexpression of lymphangiogenic factors seems to have no effect on survival of hosts in this in vivo experiment.

• Korean Journal of Plant Resources
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• v.6 no.1
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• pp.25-32
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• 1993

Many plants, which collected from Korea, were applied to antitumor and cytotoxic screeing tests against sarcom 180 a ascitec in mice, V-79 KB and P388 cultured cells. The results are summarixed as follows:1) The total packed cell volum method has been used for the antineoplastic screening for from natural higher plants in Korea. By this method, we have found out that the root, leaf and stem of Tripterygiu, regelii Spragne & Taketa having strong antineoplastic activity and also Rumex Japonicus Houtt. Eragrositis ferru-ginea Beauv. and Patrinia scabio-saefolia Fischer showed significant activity to anticancer tumor while cynanchum wilfordii Hemsley, and Rosa polyantha Sieb. et Zacc. showed slight activity to antitumor. 2) Among the 13 tested plants, the root and stem of Tripterygium regelii Spragne & Taketa and Amethystanthus excisus Nakai showed strong antitumor activity by the V79 cytotoxic cell screening test. 3) Twelve plants, which are glowing in mountainous area of Korea tested to anticancer activity. From the results, Eragrositis ferru-ginea Beauv., Angelica gigas Nakai, Geranium sibiricum L., Patrinia scabio-saefolia Fisher, Cynanchum wilfordii Hemsley, and Rubia akane Nakai have been proved to be anti-cancer plants by using P388 cell cultured method. 4) Tripterygiu, resgelii Spragne & Taketa, Eragrositis ferru-ginea Beauv., Patrinia scabio-saefoli Fisher, Cynanchum wilfordii Hemsley and Rasa polyantha Sieb. et Zacc., var. genuina Thunb. showed strong anti-tumor activity both total packed cell volume method and Cytotoxicity method.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.727-730
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• 2005

In this paper, we propose a new current sense amplifier for low-voltage, high-speed SRAM. As a supply voltage is reduced, a sensing delay is increased owing to reduced cell read current. It causes a low-speed operation in SRAM. To overcome this problem, we present a new current sense amplifier which consists of the current-mirror type circuit with feedback structure. For demonstration, a 0.8-V, 256-Kb SRAM incorporating the proposed current sense amplifier has been designed with $0.18-{\mu}m$ CMOS technology. The simulation results show 15.6ns of the sensing delay reduction in comparison with a previous current sense amplifier and 11.5ns of the sensing delay reduction in comparison with a voltage sense amplifier.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1160-1165
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• 1998

When total cellular DNA was isolated from Porphyra tenera by ultracentrifugation on Hoechst dye/CsCl gradients method, plasmid like DNA's were concentrated at the upper band which were characterized with a A＋T rich organelle DNA's in the CsCl gradients. Based on their electrophoretic migration in different concentration of agarose gel, buffer system, and electric power etc. and the results of restriction digestion, the plasmid like DNA's were concluded to have circular conformation. This is the first report of putative circular plasmid DNA from the P. tenera, which is a autonomously replicating plasmid existing with a high copy number plasmid in the cell. The minimum size of this plasmid estimated by restriction endonuclease digestion was appeared to be 2.5kb in size.

• Environmental Mutagens and Carcinogens
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• v.16 no.2
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• pp.77-82
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• 1996

The RAD3 gene of Saccharomyces cerevisiae is required for excision repair and is essential for cell viability. RAD3 encoded protein possesses a single stranded DNA-dependent ATPase and DNA-RNA helicase activies. To examine the extent of conservation of structure and function of RAD3 during eukaryotic evolution, we have cloned the RAD3 homolog, HRD3, from the distantly related yeast Schizosaccharomyces pombe. Here, we report the partial cloning and characterization of HRD3 gene (Homologous of RAD3 gene) which was isolated by PCR amplification using conserved domain of Saccharomyces cerevisiae RAD3 gene. Chromosomal DNA isolated from S. pombe had similar restriction patterns to those from S. cerevisiae, as determined by Southern blot analysis. The 2. 8 kb transcript of mRNA was identified by Northern hybridization. The level of transcript did not increase upon UV-irradiation, suggesting that the HRD3 gene in S. pombe is not UV-inducible.

• International Journal of Industrial Entomology and Biomaterials
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• v.4 no.1
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• pp.57-62
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• 2002

Cationic liposomes complexed with DNA have been extensively utilized for the delivery of reporter or therapeutic genes both in culture and in vivo. We investigated and determined the optimum conditions of a cationic liposome, composed of dimethyldioctadecy-lammonium bromide (DDAB) and dioleoyl phosphati-dylethanolamine UOPE), mediated a reporter plasmid expressing luciferase into insect cell lines (Sf-21 and Bm-N) and silkworm larvae. Together the data demonstrated that Bombyx mori nuclear polyhedrosis virus (BmNPV) genomic DNA (128 kb) was successfully transfected into Bm-5 cells using this liposome. These results suggest that DDAB/DOPE liposome will be useful as delivery agents for gene transfer to insect cells both in vitro and in vivo.

• Proceedings of the KSAR Conference
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• 2002.06a
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• pp.5-5
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• 2002

Nucleoside diphosphate kinases (NDPKs) are conserved through evolution and have been shown to be involved in various biological phenomena. By functional screening in yeast, we identified a new member of the NDPK family, ㎚23-M5, which encodes a 211-amino acid protein with 86% identify to the human homolog, ㎚23-H5. Northern blot analysis reveals that ㎚23-M5 encodes two transcripts of 0.8 and 0.7 kb, which are highly and specifically expressed in adult testis. Reverse transcriptase polymerase chain reaction analysis shows that nm23-M5 first appears in pachytene spermatocytes and increase chain reaction in abundance through subsequent stages. (omitted)

• Electrical & Electronic Materials
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• v.13 no.12
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• pp.6-9
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• 2000

Over the years of decades, the memory technology has progressed a long, marble way. As we have evidenced from the Intel's 1Kb DRAM in 1970 to the Gigabit era of 2000's, the road further ahead towards the Terabit era will be unfolded. The technology once perceived inconceivable is in realization today, and similarly roadblocks as we know of today mayvecome trivial issues for tomorrow. For the inquiring mind, the question is how the "puzzle"of tomorrow's memory technology is pieced-in today. The process will take place both in evolutionary and revolutionary ways. Among these, note-worthy are the changes in DRAM architecture and the cell process technology. In this paper, some technical approaches will be discussed to bring these aspects into a general overview and a per-spective with possibilities for the new memory technology will be presented.presented.

• Archives of Pharmacal Research
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• v.21 no.4
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• pp.470-474
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• 1998

A kanamycin producer, Streptomyces kanamyceticus IFO 13414 is highly resistant to kanamycin. Cloning of the kanamycin resistance genes in S. lividans 1326 with pIJ702 gave several kanamycin resistant transformants. Two transformants, S. lividans SNUS 90041 and S. lividan. SNUS 91051 showed similar resistance patterns to various aminoglycoside antibiotics. Gene mapping experiments revealed that plasmids pSJ5030 and pSJ2131 isolated from the transformants have common resistant gene fragments. Subcloning of pSJ5030 gave a 1.8 Kb gene fragment which showed resistance to kanamycin. Cell free extracts of S. lividans SNUS 90041, S. lividans SNUS 91051 and subclone a S. lividans SNUS 91064 showed kanamycin acetyltransferase activity. The detailed gene map is included.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.17-20
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• 2000

Over the years of decades, the memory technology has progressed a long, marble way. As we have evidenced from the Intel’s 1Kb DRAM in 1970 to the Gigabit era of 2000’s, the road further ahead towards the Terabit era will be unfolded. The technology once perceived inconceivable is in realization today, and similarly roadblocks as we know of today may become trivial issues for tomorrow. For the inquiring mind, the question is how the “puzzle” of tomorrow’s memory technology is pieced-in today. The process will take place both in evolutionary and revolutionary ways. Among these, note-worthy are the changes in DRAM architecture and the cell process technology. In this paper, some technical approaches will be discussed to bring these aspects into a general overview and a perspective with possibilities for the new memory technology will be presented.