• Macromolecular Research
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• 제16권8호
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• pp.695-703
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• 2008

Nanoparticles have tremendous potential in cancer prevention, detection and augmenting existing treatments. They can target tumors, carry imaging capability to document the presence of tumors, sense pathophysiological defects in tumor cells, deliver therapeutic genes or drugs based on the tumor characteristics, respond to external triggers to release an appropriate agent, document the tumor response, and identify the residual tumor cells. Nanoparticles < 30 nanometers in diameter show unexpected and unique properties. Furthermore, particles < 5 nanometers in size can easily penetrate cells as well as living tissues and organs. This study evaluated the safety of nano materials in a living body and the relationship between the living tissue and synthetic nano materials by examining the in-vitro cytotoxicity of poly(lactic-co-glycolic) acid (PLGA) nano-spheres and fluorescein isothiocynate(FITC)-labeled dendrimers as polymer nanoparticles. PLGA was chosen because it has been used extensively for biodegradable nanoparticles on account of its outstanding bio-compatibility and its acceptance as an FDA approved material. The dendrimer was chosen because it can carry a molecule that recognizes cancer cells, a therapeutic agent that can kill those cells, and a molecule that recognizes the signals of cell death. Cytotoxicity in L929 mouse fibroblasts was monitored using MTT assay. Microscopic observations were also carried out to observe cell growth. All assays yielded meaningful results and the PLGA nanoparticles showed less cytotoxicity than the dendrimer. These nano-particles ranged in size from 10 to 100 nm according to microscopy and spectroscopic methods.

• 약학회지
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• 제47권4호
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• pp.234-238
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• 2003

Linarin is a main compound from Chrysanthemum zawadskii var, latilobum. However, the biological mechanisms of these activities are unclear. Because of this wide diversity of effects, it is believed that they may be exerted through pluripotent effectors of linarin. In our previous screening study, the effects of linarin on the mouse macrophages cell line, RAW 264.7 cells, were investigated. It was found that linarin could stimulate macrophages activation by the production of tumor necrosis factor (TNF). The linarin (6.25∼12.5 $\mu\textrm{g}$/mι) inhibited the production of NO in LPS-activated RAW 264.7 cells and linarin became an useful candidates for the development of new drug to treat endotoxemia and inflammation accompanied by the overproduction of NO. However, linarin-treated total lymphocyte showed cytotoxicity in a dose dependent manner between 20 $\mu\textrm{g}$/mι and 40 $\mu\textrm{g}$/mι. In this study, linarin derivative (acetylated linarin) was synthesized in order to obtain less-cytotoxicity of linarin and evaluated for their in vitro cytotoxic activity aganist mouse total lymphocyte. There was no cytotoxic activity in a dose dependent manner (20∼40 $\mu\textrm{g}$/mι) of acetylated linarin whereas linarin showed. The production of NO, however, was not the case by this modified linarin. The cell morphological change was not significantly changed in response to acetylated linarin alone and these effects were potentiated by the addition of LPS. These results suggest that acetylated linarin may be developed to be a promising new drug candidate without cytotoxicity on the basis of its activity of macrophage activation.

• Biomolecules & Therapeutics
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• 제20권3호
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• pp.306-312
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• 2012

Resveratrol (trans-3,5,4'-trihydroxystilbene) has received considerable attention recently for the potential neuroprotective effects in neurodegenerative disorders where heme oxygenase-1 (HO-1) and sirtuin 1 (SIRT1) represent promising therapeutic targets. Resveratrol has been known to increase HO-1 expression and SIRT1 activity. In this study, the effects of resveratrol and trans-3,5,4'-trimethoxystilbene (TMS), a resveratrol derivative, on cytotoxicity caused by glutamate-induced oxidative stress, HO-1 expression, and SIRT1 activation have been investigated by using murine hippocampal HT22 cells, which have been widely used as an in vitro model for investigating glutamate-induced neurotoxicity. Resveratrol protected HT22 neuronal cells from glutamate-induced cytotoxicity and increased HO-1 expression as well as SIRT1 activity in a concentration-dependent manner. Cytoprotection afforded by resveratrol was partially reversed by the specific inhibition of HO-1 expression by HO-1 small interfering RNA and the nonspecific blockage of HO-1 activity by tin protoporphyrin IX, but not by SIRT1 inhibitors. Surprisingly, TMS, a resveratrol derivative with methoxyl groups in lieu of the hydroxyl groups, and trans-stilbene, a non-hydroxylated analog, failed to protect HT22 cells from glutamate-induced cytotoxicity and to increase HO-1 expression and SIRT1 activity. Taken together, our findings suggest that the cytoprotective effect of resveratrol was at least in part associated with HO-1 expression but not with SIRT1 activation and, importantly, that the presence of hydroxyl groups on the benzene rings of resveratrol appears to be necessary for cytoprotection against glutamate-induced oxidative stress, HO-1 expression, and SIRT1 activation in HT22 neuronal cells.

• Journal of Preventive Medicine and Public Health
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• 제30권3호
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• pp.555-566
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• 1997

This study was carried out to evaluate the cytotoxicity of rock wool fibers(RWFs) such as cell division disturbance, chromosomal and DNA damage, and mutagenicity using cultured cells. RWFs were the man made mineral fibers. In order to find the correlation between the cytotoxicity of RWFs and the phagocytic capacity of cells, the phagocytic processes were observed using scanning electron microscope. Cell division disturbance by RWFs was evaluated by the formation of multinucleated giant cells. The chromosomal damage was evaluated by the micronucleus formation. For the evaluation of oxidative DNA damage, 8-hydroxy-2'-deoxyguanosine (8-OH-dG) formation was measured utilizing calf thymus DNA. Mutagenicity was determined by the point mutation of HGPRT and the effect of RWFs on cell transformation was also observed. 1. Compared with the results of chrysotile, RWFs were no or little effect on the cell growth according to the results done by the tests of cell proliferation inhibition and relative plating efficiency. 2. The frequency of multinucleated giant cell formation was increased by the treatment of RWFs and it was dose-dependent. However, the effect of RWFs was weaker than that of chrysotile. 3. The number of micronuclei formed in the RWFs treated cells was between those of cells treated with chrysotile and those of untreated cells. 4. The 2 fold increase in the formation of 8-OH-dG in calf thymus DNA was observed in the cells treated with RWFs in the presence of $H_2O_2$. On the other hand, chrysotile had no effect on the 8-OH-dG formation. 5. RWFs had no effect on the HGPRT point mutation and cell transformation. These results showed that RWFs could induce chromosomal damage, cell division disturbance and oxidative DNA damage in the RWFs treated cells.

• Journal of Photoscience
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• 제9권2호
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• pp.515-517
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• 2002

Photodynamic therapy (PDT) is a cancer treatment modality which utilizes the cytotoxicity of the active singlet oxygen derived from irradiation of a tumor accumulated photosensitizer. As the oxygen in the singlet state radiates an emission of 1270nm wavelength when it decays to the triplet state, detection of the emission helps us to understand the mechanism of PDT or to evaluate photosensitizers. We detected the 1270nm emission from photosensitizers Photofrin and ATX-SI0 in vitro and in vivo by means of high sensitive NIR detectors. We obtained the maximum amount of singlet oxygen at irradiation wavelength of 665-670nm from a HeLa tumor in a nude mouse which is injected with ATX-S10.

• 한방안이비인후피부과학회지
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• 제13권1호
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• pp.129-140
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• 2000

ShingongNaetakSan(SNS) was drugs used in treatment of carbuncle and cellulitis in Oriental So, the purpose of this Study was to investigate effect of SNS on the proliferation of immunocytes and anti-cancer. This Study estimated the proliferation of L1210 cell lines and S-180 cell lines in vitro. and estimated the proliferation of L1210 cells, thymocytes and splenocytes, and tumor weight, body weight and mean survival rates in vivo. The proliferation and cytotoxicity of cells was tested using a colorimetric tetrazoliun assy(MTT assy). The results of this study were obtained as follow ; SNS had effect on the proliferation of L1210 cells in vitro and splenocytes in vivo, and SNS decreased significantly tumor weight, and increased significantly mean survival rates.

• Parasites, Hosts and Diseases
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• 제49권1호
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• pp.1-8
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• 2011

The pathogenesis and pathophysiology of Acanthamoeba infections remain incompletely understood. Phospholipases are known to cleave phospholipids, suggesting their possible involvement in the host cell plasma membrane disruption leading to host cell penetration and lysis. The aims of the present study were to determine phospholipase activities in Acanthamoeba and to determine their roles in the pathogenesis of Acanthamoeba. Using an encephalitis isolate (T1 genotype), a keratitis isolate (T4 genotype), and an environmental isolate (T7 genotype), we demonstrated that Acanthamoeba exhibited phospholipase $A_2$ (PLA$_2$). and phospholipase D (PLD) activities in a spectrophotometry-based assay. Interestingly, the encephalitis isolates of Acanthamoeba exhibited higher phospholipase activities as compared with the keratitis isolates, but the environmental isolates exhibited the highest phospholipase activities. Moreover, Acanthamoeba isolates exhibited higher PLD activities compared with the PLA$_2$. Acanthamoeba exhibited optimal phospholipase activities at $37^{\circ}C$ and at neutral pH indicating their physiological relevance. The functional role of phospholipases was determined by in vitro assays using human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. We observed that a PLD-specific inhibitor, i.e., compound 48/80, partially inhibited Acanthamoeba encephalitis isolate cytotoxicity of the host cells, while PLA$_2$-specific inhibitor, i.e., cytidine 5'-diphosphocholine, had no effect on parasite-mediated HBMEC cytotoxicity. Overall, the T7 exhibited higher phospholipase activities as compared to the T4. In contract, the T7 exhibited minimal binding to, or cytotoxicity of, HBMEC.

• 약학회지
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• 제41권5호
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• pp.629-637
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• 1997

Tumor necrosis factor-${alpha}$ (TNF) induced a cytotoxic response in ME-180 cervical carcinoma cells in vitro. This cytotoxic response was accompanied by a temporal series of mitogenic stimuli : increased c-fos, c-jun and jun-B expression. Depletion of protein kinase C (PKC) by exposure of ME-180 cells to 100ng/ml phorbol myristate acetate (PMA) for 24hours almost completely abolished TNF-mediated increase in these signals, indicating that a PKC-dependent pathway is involved in TNF-mediated increases in the expression of c-fos, c-jun and jun-B. Characteristics of TNF receptors after exposure to 100ng/ml PMA or 24hours were not altered, suggesting that diminished induction of these oncogenes by TNF after PMA treatment is not due to any changes at the receptor level. To examine whether a PKC-dependent pathway is involved in TNF-mediated cytotoxicity in ME-180 cells, cytotoxicity was measured after depletion of PKC. No apparent changes in cytototoxicity after PKC depletion suggest that a PKC-dependent pathway is not involved in TNF-mediated cytotoxicity. Furthermore, results from cytotoxicity tests after exposure to staurosporine (PKC inhibitor) did not show any changes in the TNF-mediated cytotoxicity, confirming that a PKC-dependent pathway is not involved in this process. These data indicate that 1) TNF induces expression of c-fos, c-jun and jun-B oncogenes via a PKC-dependent pathway and 2) PKC-dependent expression of these three oncogenes by TNF may not be involved in TNF-mediated cytotoxicity in ME-180 cells.

• 한국독성학회:학술대회논문집
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• 한국독성학회 2003년도 춘계학술대회 논문집
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• pp.57-57
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• 2003

Epidemiological studies of arsenic have shown that chronic exposure to arsenic can result in an increased incidence of cancer of the lung, skin, bladder and liver. It is impossible that the toxicity study of arsenic in the human, we become to measure in vitro cytotoxicity of inorganic and organic arsenic in the human normal liver cells including Chang Liver and WRL. (omitted)

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 1999년도 The 6th International Symposium on the Development of Anti-Cancer Resource from Plants
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• pp.84-89
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• 1999

The present study has been undertaken to detect edible medicinal plants with antineoplastic property on the basic of a number of traditional Korean medical literatures, besides studies on development of anti-cancer medical wild plants growing in Korea and to prove experimentally their efficacy by in vitro and in vivo tests.235 species from 45 family 79 genus were screened primarily as edible sources of antitumor effect. Among those the crude. extracts of 40 spp. showed considerable cytotoxicity in vitro and especially Pegangkuen(Patrinia scabiosaefolia), Deod-eog(Codonopsis lanceolata), Okssusu(Zea may), and Geureong(Eragrositis ferru-ginea) exhibited significant antitumor activity against sarcoma 180 asites mice. However, additional researches should be mode for the confirmation of their availability as antitumor plants.