• Archives of Pharmacal Research
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• v.22 no.4
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• pp.340-347
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• 1999

Dendritic cells (DCs) are potent professional antigen-presenting cells (APC) capable of inducing the primary T cell response to antigen. Although tumor cells express target antigens, they are incapable of stimulating a tumor-specific immune response due to a defect in the costimulatory signal that is required for optimal activation of T cells. In this work, we describe a new approach using tumor-DC coculture to improve the antigen presenting capacity of tumor cells which does not require a source of tumor-associated antigen. Immunization of a weakly immunogenic and progressive tumor cocultured with none marrow-derived DCs generated an effective tumor vaccine. Immunization with the cocutured DCs was able to induce complete protectiv immunity against tumor challenges and was effective for the induction of tumor-specific CTL (cytotoxic T lymphocyte) activity. Furthermore, high NK cell activity was observed in mice in which tumors were rejected. In addition, immunization with tumor-pulsed DC s induced delayed tumor growth, but not tumor eradication in tumor-bearing mice. Our results demonstrate that coculture of DCs with tumors generated antitumor immunity due to the NK cell activation as well as tumor-specific T cell. This approach would be used for designing tumor vaccines using DCs when the information about tumor antigens is limited.

• Journal of the Korean institute of surface engineering
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• v.17 no.2
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• pp.29-40
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• 1984

The structure of rapidly solidified Al-Si-based alloys and its relationship to subsequent anodic film growth in near neutral and acid solutions have been investigated. Solidification of the alloys proceeds via pre-dendritic nuclei, associated with rugosity of the casting surface, from which cellular-type growth, comprised of aluminium-rich material surrounded by silicon-containing material, emanates. Observation of ultramicrotomed sections of the alloys and their anodic films reveals the local oxidation of the silicon-rich phase and its incorporation into the anodic alumina film, formed in near neutral solutions. Such incorporation occurs but resultant isolation of the silicon-rich phase is not possible for anodizing in phosphoric acid, and a three-dimensional network of the oxidized silicon-containing phase, with continuing development of porous anodic alumina, is observed.

• Clinical and Experimental Pediatrics
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• v.54 no.6
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• pp.241-245
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• 2011

Tuberous sclerosis complex (TSC) is a genetic multisystem disorder that results from mutations in the TSC1 or TSC2 genes, and is associated with hamartomas in several organs, including subependymal giant cell tumors. The neurological manifestations of TSC are particularly challenging and include infantile spasms, intractable epilepsy, cognitive disabilities, and autism. The TSC1- and TSC2-encoded proteins modulate cell function via the mammalian target of rapamycin (mTOR) signaling cascade, and are key factors in the regulation of cell growth and proliferation. The mTOR pathway provides an intersection for an intricate network of protein cascades that respond to cellular nutrition, energy levels, and growth factor stimulation. In the brain, TSC1 and TSC2 have been implicated in cell body size, dendritic arborization, axonal outgrowth and targeting, neuronal migration, cortical lamination, and spine formation. The mTOR pathway represents a logical candidate for drug targeting, because mTOR regulates multiple cellular functions that may contribute to epileptogenesis, including protein synthesis, cell growth and proliferation, and synaptic plasticity. Antagonism of the mTOR pathway with rapamycin and related compounds may provide new therapeutic options for TSC patients.

• Journal of the Korean Ceramic Society
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• v.25 no.2
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• pp.161-167
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• 1988

Yttria-Stabilized Cubic Zirconia Crystals with Various Y2O3 amounts (6-15mol%) were grown by the Skull melting technique. The modeling of the nucleation at the Skull bottom and the best growth condition were studied. The abrupt changes in generator heating Power and lowering rate of crucible caused the dendritic growth in the grown crystal. The optimum condition of cubic Zirconia single crystals was obtained when the lowering rate was gradually increased. The effect of Y2O3 amounts on the perfection adn the color of the grown crystal were determined. The darkish color generated in the crystals added Y2O3 amounts over 12mol% was eliminated by the annealing in air at 1200$^{\circ}C$ for 24hrs.

• Proceedings of the Korean Society of Life Science Conference
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• 2005.04a
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• pp.108-108
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• 2005

• Journal of the Korean institute of surface engineering
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• v.19 no.2
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• pp.44-50
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• 1986

Effects of cathodic overvoltages on the electrodeposition of lead from electrolyte containing lead chloride, ammonium acetate and sodium succinate was investigated at 20$^{\circ}C$. The use of organic additives, phenol and gelatin was found effective to inhibit the growth of dendritic crystals. At the carthodic overvoltages higher than 0.2V, the lead deposit becames less compact even in the presence of organic additives. The applications of agitation and pulse current promoted compact and shiny deposits.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06a
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• pp.139-156
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• 1996

The phase field model is becoming the model of choice for the theoretical study of the morphologies of crystals growth from the melt. This model provides an alternative approach to the solution of the classical (sharp interface) model of solidification by introducing a new variable, the phase field, Ø, to identify the phase. The variable Ø takes on constant values in the bulk phases and makes a continuous transition between these values over a thin transition layer that plays the role of the classically sharp interface. This results in Ø being governed by a new partial differential equation(in addition to the PDE's that govern the classical fields, such as temperature and composition) that guarantees (in the asymptotic limit of a suitably thin transition layer) that the appropriate boundary conditions at the crystal-melt interface are satisfied. Thus, one can proceed to solve coupled PDE's without the necessity of explicitly tracking the interface (free boundary) that would be necessary to solve the classical (sharp interface) model. Recent advances in supercomputing and algorithms now enable generation of interesting and valuable results that display most of the fundamental solidification phenomena and processes that are observed experimentally. These include morphological instability, solute trapping, cellular growth, dendritic growth (with anisotropic sidebranching, tip splitting, and coupling to periodic forcing), coarsening, recalescence, eutectic growth, faceting, and texture development. This talk will focus on the fundamental basis of the phase field model in terms of irreversible thermodynamics as well as it computational limitations and prognosis for future improvement. This work is supported by the National Science Foundation under grant DMR 9211276

• Journal of Welding and Joining
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• v.6 no.4
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• pp.16-26
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• 1988

The effect of carbon content on hot cracking of welded carbon steel was investigated Eight steel plates whose carbon content range from 0.02 to 0.23 percent were welded by autogeous gas tungsten are process. Constant strain was applied to the hot crack test specimen under the strain rate of 0.15 mm per second during welding. The hot cracking susceptibility ws high in the rnage of 0.02-0.05 and 0.12-0.23 percent carbon contents. The critical carbon content immune to hot cracking is in the range from 0.07 to 0.12 percent carbon. By electron probe microanalyser, amanganese segregation was not seen significantly in the whole carbon range. But segregation of silicon was higher in the region of low carbon contents. However, sulphur was segregated remarkably in the region betwen 0.18 and 0.23 percent carbon by peritectic reaction. Very smal lamount of dnedritic structure was observed in the region from 0.02 to 0.05 percent carbon by peritectic reaction. Very small amount of dendritic structure was observed in the region from 0.02 to 0.05 percent carbon but the predominant solidification structure was smooth by cellular growth. The higher the carbon content is, the more the columnar dendritic structure was observed.

• Journal of Environmental Science International
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• v.1 no.2
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• pp.49-57
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• 1992

First, We classified man-made lakes in Korea as 4-type lakes, that is, there were River-run lakes, Dendritic lakes, Reservoir-lakes, River-mouth lakes, We studied on the environmental factors of 3-type lakes except River-mouth lakes, compared these lakes with natural lakes in foreign country. Environmental factors were watershed area, lake storage, mean depth, hydraulic retention time. As a results, 3-type lakes in Korea had remarkable differences one another according to above-mentioned environmental factors. First, We recognized that River-run lakes had higher nutrient loading according to having wider watershed area than natural lakes, and had lower algal growth rate according to shorter hydraulic retention time than natural lakes. Dendritic lake had higher nutrient loading than natural lakes, longer retention time than River-run lake. Reservoir-lakes had environmental factors between Dentritic lakes and River-run lakes. Therefore, If this studies had no quantitative results about various factors, We recognized that man-made lakes in korea had different environmental factors as compared with natural lakes, and had clear classification among 3-type lakes.

• IMMUNE NETWORK
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• v.3 no.3
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• pp.176-181
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• 2003

Background: The molecular basis of follicular dendritic cells (FDC)-germinal center (GC) B cell interaction is largely unknown, although this cellular interaction is thought to be important for the whole process of GC B cell differentiation. Methods: Using FDC-like cells, HK, and highly purified GC B cells, we attempted to identify the molecules that play critical roles in the interactions between FDC and B cells. GC B cells were co-cultured with HK cells and soluble CD154 in the presence or absence of various function-blocking monoclonal antibodies to examine their effect on GC B cell binding to HK cells and B cell proliferation. Results: Anti-CD11a and anti-CD54 antibodies inhibited GC B cell binding to HK cells while anti-CD49d and anti-CD106 antibodies did not. GC B cell proliferation was not impaired by the disruption of GC B cell-HK cell adherence. Conclusion: Our results suggest that CD11a/CD18-CD54 interactions play an important roles in the initial binding of GC B cells to FDC and diffusible growth factors from FDC may be responsible the massive proliferation of GC B cells.