• Biomedical Science Letters
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• v.13 no.4
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• pp.333-339
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• 2007

Recently, much attention has been paid to human retinoblastoma since it provide a good model system for studying mechanisms underlying cell growth, differentiation, proliferation, and apoptosis, and for developing cancer therapy. However, until now it is unclear whether purinergic receptors are involved in the calcium mobilization in the retinoblastoma cells. In this regard, we measured possible purinergic signaling in WERI-Rb-1 cells using $Ca^{2+}$ imaging technique and RT-PCR method. ATP-induced $[Ca^{2+}]_i$ transients was maintained to about $90.7{\pm}1.0%$ of the control (n=48) even in the absence of extracellular calcium. The ATP-induced intracellular calcium response was only attained to $10.4{\pm}1.8%$ (n=55) of peak amplitude of the control after preincubation of 1 ${\mu}MU-73122$, a PLC inhibitor, but it was not affected by 1 ${\mu}MU-73343$, a inactive form of U-73122. And also ATP-induced $[Ca^{2+}]_i$ rise was almost attenuated by 20 ${\mu}M$ 2-APB, a putative $IP_3$ receptor inhibitor. Two subtypes of $IP_3$ receptor $(IP_{3-1}R,\;IP_{3-2}R)$ were identified by a RT-PCR method. These findings suggest that purinergic stimuli can cause calcium mobilization via $PLC-IP_3$ pathway after the activation of P2Y receptors in the retinoblastoma cells, which may play important roles in cell proliferation, differentiation, growth, and cell death.

• Applied Microscopy
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• v.47 no.4
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• pp.238-241
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• 2017

A study on the visual cell and eyeball of the endemic Korean species Liobagrus mediadiposalis was investigated by light and electron microscopes. The retina of a small and 2 mm-diameter round eye was thin, $151.0{\pm}4.0{\mu}m$ and has two visual cells, a single cone and a rod cell. The single cone cells are short and thick, $18.0{\pm}0.9{\mu}m$ in length and $5.1{\pm}0.7{\mu}m$ (n=30) in diameter, while the rod cells are longer and thinner, $54.8{\pm}2.9{\mu}m$ in length and $3.3{\pm}0.6{\mu}m$ in diameter. The cone cells are seen an irregular and random mosaic pattern, and the rod cells are also randomly situated at between cone cells. As a rare phenomenon, such structure is one of characteristics reflecting the eye of a nocturnal and bottom-dwelling freshwater fish. The ultrastructure of visual cells was observed with scanning and transmission electron microscopy, both cone and rod cells are divided into an inner segment with numerous mitochondria and an outer segment with stacks of membrane discs.

• Applied Microscopy
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• v.15 no.2
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• pp.89-97
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• 1985

The ultrastructure of the trachea of the compound eye in adult cabbage butterfly, Pieris rapae L., was studied. Trachea under the basement membrane is divided into tracheoles of the ommatidia which blanched 4 tracheoles during 2 divisions. Tracheoles of the ommatidia originated from one tracheolar cell and its nuclear is located under the basement membrane and its cytoplasm enveloped the retinular cell and the retinular pigment cell. The modified structure of tracheoles is located at the first division area of the ommatidia and its size is $8{\mu}mX4.5{\mu}m$. And the length of its taenidium is $0.1{\sim}0.6{\mu}m$, diameter $0.15{\mu}m$, and interval $0.3{\mu}m$.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.64.1-64.1
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• 2011

다중접합 태양전지는 흡수대역이 다른 juntion으로 구성되어, 각각의 태양전지 간의 전류정합(current matching)이 효율 향상에 중요하다. 본 실험에서는 Top cell에 i-a-Si:H(Thinckness:100nm), Middle cell에는 i-a-SiGe:H(Thickness:800nm)을 적용하였고, bottom cell에는 i-${\mu}c$-Si:H(Thickness:1800nm), 수광부의 p-layer에 에 SiOx을 이용하여 triple juntion amorphous silicon solar cell(삼중접합태양전지)을 구현하였다. 이를 최적화 시키기 위해 ASA simulation을 이용하여 각 Cell의 intrinsic layer의 밴드갭을 가변하였다. 가변 결과 i-a-Si:H : 1.85 eV, i-a-SiGe:H: 1.6 eV, i-${\mu}c$-Si:H: 1.4 eV에서 태양전지 효율 14.5 %을 기록 하였다. 본 연구를 통해 Triple juntion cell에서의 intrinsic layer의 밴드갭 최적화를 구현해 볼 수 있었다.

• Applied Microscopy
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• v.13 no.1
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• pp.41-47
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• 1983

A Scanning electron microscope which can obtain additional information not readily available with either the light or transmission electron microscope was used to study the mast cell shape and its granules in normal mammal tissue(rat mesentery, stomach and mouse stomach) by fretting cut using liquid nitrogen. The results showed that rat mesentery and mouse stomach mast cell surfaces had no ridges and microvilli, but revealed several microvilli projecting into the surrounding connective tissue in the rat stomach mast cell. The shape of the mast cell varied from discoid(in the rat mesenteric mast cell) to ellipsoid (rat and mouse stomach), ranging from 7.5 to $10{\mu}m$ in diameter. The shape of the nucleus was ellipsoid and nucleic membrane was adherent to the outer surface of the granules. The granules, approximately 0.2 to $0.9{\mu}m$ in diameter, were various shapes. Frequently, rounded protrusions of cytoplasmic granules could be discerned under the cell membrane. Many small granules were seen in the cytoplasm.

• Applied Microscopy
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• v.13 no.1
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• pp.63-70
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• 1983

The cell division of Bacillus thuringiensis are studed by a electron microscope. It was observed that when the cell division was occurred, the bacterial transverse septeum was centripetally formed, and the bacterial spore was divided into two daughter cells. The fore spore septum was initiated by invagination from either sides of the cell membranes, and was easily distinguished it from the transverse septum of the vegetative cell division. The large vesicular mesosome was. observed at one end of the cell membrane. The nucleoids were of variously irregular shapes and had no a nuclear membrane. The morphology of the bacteria was visualizd by a scanning electron microscope. The surface of the cell was generally rough and had a single polar flagellum, which was appeared to be $0.2{\mu}$ in width and $13{\mu}$ in length.

• Natural Product Sciences
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• v.13 no.2
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• pp.135-139
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• 2007

Four anthocyanins were isolated from the acidic alcoholic extract of Syzygium cumini fruits growing in Egypt: Pelargonidin-3-O-glucoside, pelargonidin-3,5-O-diglucoside, cyanidin-3-O-malonyl glucoside, and delphenidin-3-O-glucoside. They were identified by the chromatographic, TLC and PC, and spectral analyses, UV, $^1$H-NMR and FAB/MS. The fruits were found to contain 0.03 gm % anthocyanins calculated on fresh weight basis calculated by spectrophotometric assay. Cytotoxic activity of total alcoholic extract of the fruits was performed against several types of tumor cell lines using the SRB assay. The tested extract exhibited significant cytotoxic activity for MCF7 (breast carcinoma cell line) (IC$_{50}$= 5.9 ${\mu}$g/mL), while the IC$_{50}$ was > 10 ${\mu}$g/mL for both Hela (Cervix carcinoma cell line), HEPG2 (liver carcinoma cell line), H460 (Lung carcinoma cell line) and U251 (Brain carcinoma cell line).

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.987-992
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• 1998

This study was investigated to observe the cytotoxicity effect of Ligularia fischeri extracts against cancer cell lines including human lung carcinoma(A549), human cervix epitheloid carcinoma(HeLa) and human hepatocellular carcinoma(HepG2) using SRB(sulforhodamine B) method. The ethanol and methanol extracts of 1$\mu\textrm{g}$/${mu}ell$ showed approximately 79.2% and 86.4% cytotoxicity effects on HepG2 cell line and the ethyl acetate fracton fractionated from ethanol extracts showed the strongest cytotoxicity effect with 94% inhibition. The inhibitory effect of ethanol extract on HeLa cell line was somewhat low with 50~56% inhibition, but ethyl acetate fraction showed higher cytotoxicity effect with 91% and 91.9% inhibition on the HeLa and A549 cell line. On the contrary, the ethanol and methanol extracts showed the lower inhibition effects on the normal liver cell, WRL68, compared to human cancer cell lines.

• YAKHAK HOEJI
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• v.38 no.1
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• pp.6-11
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• 1994

The MeOH extract of the fruits of Melia toosendan was selected for futher study by its cytotoxicity and effect on the human breast cancer cell line, MCF-7. The active principle obtained by activity guided fractionation followed by purification gave rise to a needle crystal. The structure was deduced by employing NMR and was determined to be identical with 28-deacetyl sendanin by comparison with published data. This compound induced morphological change of MCF-7 to be rounded with tubule at concentrations between $50\;{\mu}g/ml$ and $0.025\;{\mu}g/ml$. This compound, however, showed strong cytotoxic effect on Hepalclc7 and HepG2, and their $GI_{50}$ on the hepatoma cell lines were $0.238\;{\mu}g/ml$ and $0.805\;{\mu}g/ml$, respectively. Its effect on lymphocyte of mouse was stronger than hepatoma cell lines, and their $ED_{50}$ of polyclonal antibody response was $0.011\;{\mu}g/ml$, and $ED_{50}$ of cell viability was $0.039\;{\mu}g/ml$.

• The Korean Journal of Physiology and Pharmacology
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• v.21 no.5
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• pp.465-474
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• 2017

The aim of this study was to determine the raising anticancer effects of resveratrol (Res) on paclitaxel (PA) in non-small cell lung cancer (NSCLC) cell line A549. The $10{\mu}g/ml$ of Res had no effect on human fetal lung fibroblast MRC-5 cells or on A549 cancer cells and the 5 or $10{\mu}g/ml$ of PA also had no effect on MRC-5 normal cells. PA-L ($5{\mu}g/ml$) and PA-H ($10{\mu}g/ml$) had the growth inhibitory effects in NSCLC cell line A549, and Res increased these growth inhibitory effects. By flow cytometry experiment, after Res ($5{\mu}g/ml$)+PA-H ($10{\mu}g/ml$) treatment, the A549 cells showed the most apoptosic cells compared to other group treatments, and after additional treatment with Res, the apoptosic cells of both two PA concentrations were raised. Res+PA could reduce the mRNA and protein expressions of COX-2, and Res+PA could reduce the COX-2 related genes of VEGF, MMP-1, MMP-2, MMP-9, $NF-{\kappa}B$, Bcl-2, BclxL, procollagen I, collagen I, collagen III and CTGF, $TNF-{\alpha}$, $IL-1{\beta}$, iNOS and raise the TIMP-1, TIMP-2, TIMP-3, $I{\kappa}B-{\alpha}$, p53, p21, caspase-3, caspase-8, caspase-9, Bax genes compared to the control cells and the PA treated cells. From these results, it can be suggested that Res could raise the anticancer effects of PA in A549 cells, thus Res might be used as a good sensitizing agent for PA.