• Animal cells and systems
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• v.11 no.2
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• pp.199-204
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• 2007

HCN (hyperpolarization-activated cyclic nucleotide-gated) channels, whose gene family consists of four subunits (HCN1-4), mediate depolarizing cation currents and contribute to controlling neuronal excitability. In the present study, immunohistochemical and electrophysiological approaches were used to elucidate the role of HCN channels in the cerebellum. Immunohistochemical labeling for HCN1 and HCN2 channels revealed localized expression of both channels at pinceau, the specialized structure of presynaptic axon terminals of basket cells. To determine the functional role of the presynaptic HCN channels, spontaneous inhibitory postsynaptic currents (IPSCs) were recorded from Purkinje cells, the main synaptic targets of basket cells in the cerebellum. While activation of HCN channels by 8-bromo-cAMP increased amplitude of spontaneous IPSCs, blockade of the activated HCN channels by subsequent ZD7288 application reduced the amplitude of spontaneous IPSCs to the level far below the control. Our results imply that modulation of HCN1 and HCN2 channels in presynaptic terminals of basket cells regulates neurotransmitter release, thereby controlling the excitability of Purkinje cells.

• The Korean Journal of Cytopathology
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• v.6 no.2
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• pp.199-203
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• 1995

Chordoma is relatively uncommon tumor comprising $1\sim4%$ of primary malignant bone tumors, and believed to arise from the remnants of notochordal tissue. Because of its rare occurrence in the thoracic spine, we report a case of chordoma involving the thoracic spine. A 45-year-old male was sufferred from chest pain radiating to the back. Chest CT showed a well marginated, round huge mass with multiseptated enhancement at the thoracic spine from T5 to T8 level. After percutaneous needle aspiration, piecemeal resection of the tumor was done. On cytologic smears, two types of neoplastic cells were arranged in sheets and cords in mucinous background. One type of cells consisted of medium sized cells with pink cytoplasm and round nuclei. The other type had voluminous bubbly or clear cytoplasm divided by intracytoplasmic septae imparting a feathery or basket-like appearance. Histologically, the tumor showed lobulated feature divided by fibrous septae and the tumor cells were pink eosinophilic or physaliphorous in morphology. Immunohistochemically, the tumor cells revealed strong positivity for low(AE1) and high (AE3) molecular weight cytokeratins.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.11B
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• pp.1030-1037
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• 2008

This paper presents an algorithm for the path-finding problem in unknown environments with cooperative and commutative multi-robots. To verify the algorithm, we investigate the problem of escaping through the exit of a randomly generated maze by muti-robots. For the purpose, we adopt the so called frontier cells and cell utility functions, which were used in the exploration problem for the multi-robots. For the wireless communications among the mobile robots, we modify and utilize the so called the random basket routing, a kind of hop-by-hop opportunistic routing. A mobile robot, once it finds the exit, will choose its next action, either escape immediately or stay-and-relay the exit information for the others, where the robot takes one action based on a given probability. We investigate the optimal probability that minimizes the average escaping time (out of the maze to the exit) of a mobile robot.

• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.711-719
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• 2018

BACKGROUND: Collagen organization within tissues has a critical role in wound regeneration. Collagen fibril diameter, arrangements and maturity between connective tissue growth factor (CTGF) small interfering RNA (siRNA) and mismatch scrambled siRNA-treated wound were compared to evaluate the efficacy of CTGF siRNA as a future implement for scar preventive medicine. METHODS: Nanocomplexes of CTGF small interfering RNA (CTGF siRNA) with cell penetrating peptides (KALA and $MPG^{{\Delta}NLS}$) were formulated and their effects on CTGF downregulation, collagen fibril diameter and arrangement were investigated. Various ratios of CTGF siRNA and peptide complexes were prepared and down-regulation were evaluated by immunoblot analysis. Control and CTGF siRNA modified cells-populated collagen lattices were prepared and rates of contraction measured. Collagen organization in rabbit ear 8 mm biopsy punch wound at 1 day to 8 wks post injury time were investigated by transmission electron microscopy and histology was investigated with Olympus System and TS-Auto software. CONCLUSION: CTGF expression was down-regulated to 40% of control by CTGF siRNA/KALA (1:24) complexes (p<0.01) and collagen lattice contraction was inhibited. However, down-regulated of CTGF by CTGF $siRNA/MPG^{{\Delta}NLS}$ complexes was not statistically significant. CTGF KALA-treated wound appeared with well formed-basket weave pattern of collagen fibrils with mean diameter of $128{\pm}22nm$ (n = 821). Mismatch siRNA/KALA-treated wound showed a high frequency of parallel small diameter fibrils (mean $90{\pm}20nm$, n = 563). CONCLUSION: Controlling over-expression of CTGF by peptide-mediated siRNA delivery could improve the collagen orientation and tissue remodeling in full thickness rabbit ear wound.

• Journal of the Korea Organic Resources Recycling Association
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• v.5 no.1
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• pp.43-52
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• 1997

This study was conducted to analysis citizen's attitude and style to the foodwaste from loth Sept. to 30th Sept. in 1996. The research was used questionare method and the analysis was used prequency analysis and cross table method by SPSS (scientific statistics). they answered that the most serious environment problem was waste problem and the best way to settle waste problem was to reduce waste production itself. And they answered that to settle environment problems, it was most important for us to change our life style. But It was not agreed between consciousness and action(execution). Because most of the food-related waste was among household waste, it's settlement was the most importment thing than any other. Nevertheless the seperation of waste was essential to effective incineration, the seperation process was not actually conducted and only a few housewife knew the difference of incinerable and non-incinerable waste. The recycling for the disused dry-cells and garbage is not completly. But we think that if the effective government's recycling counterplan for wastes, foodwaste or wasted dry cell, etc., is estabilished, rates of seperation and collection was increasing. Much usuage of onetime vinyl bag for shopping was become the one of the main cause in increasing the package waste, and so it was needed to use the longlife shopping basket.