• Polymer(Korea)
• /
• v.39 no.1
• /
• pp.71-77
• /
• 2015

We synthesized a low band gap alternating copolymer containing electron-rich units (i.e. dithienosiloles and benzodithiophenes) and electron-deficient units (i.e. difluorobenzothiadiazoles) for high performance organic solar cells. The polymer was prepared by the Stille coupling reaction and characterized using $^1H$ NMR, GPC, TGA, UV-visible absorption spectroscopy, and cyclic voltammetry. Solar cells were fabricated in a structure of ITO/PEDOT:PSS/polymer: $PC_{70}BM/Al$ with five different blending ratios of polymer and $PC_{70}BM$ (1:1.5, 1:2, 1:3, 1:3.5 and 1:4 by weight ratio). The best efficiency was achieved from the 1:3 ratio of polymer and $PC_{70}BM$ in the photoactive layer, and TEM revealed that there is an optimal nanoscale phase separation between polymer and $PC_{70}BM$ in the 1:3 ratio blend film.

• BMB Reports
• /
• v.44 no.5
• /
• pp.312-316
• /
• 2011

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and its toxic metabolite 1-methyl-4-phenylpyridium ion (MPP$^+$) have been shown to induce Parkinson's disease-like symptoms as well as neurotoxicity in humans and animal species. Recently, we reported that maintenance of redox balance and cellular defense against oxidative damage are primary functions of the novel antioxidant enzyme cytosolic NADP$^+$-dependent isocitrate dehydrogenase (IDPc). In this study, we examined the role of IDPc in cellular defense against MPP$^+$-induced oxidative injury using PC12 cells transfected with IDPc small interfering RNA (siRNA). Our results demonstrate that MPP$^+$-mediated disruption of cellular redox status, oxidative damage to cells, and apoptotic cell death were significantly enhanced by knockdown of IDPc.

• Animal cells and systems
• /
• v.9 no.3
• /
• pp.173-179
• /
• 2005

Cyclic-AMP-dependent protein kinase (PKA) seems to function as a negative regulator of the c-Jun $NH_2-terminal$ kinase (JNK) signaling pathway. We demonstrate here that the activity of the PKA catalytic subunit (PKAc) is reduced in apoptotic PC12 pheochromocytoma cells. Apoptotic progress was inhibited by dibutyryl cyclic AMP (dbcAMP), an analog of cAMP. The rescue by dbcAMP was attributable to inhibition of the JNK but not of the p38 signaling pathway, due to the induction of PKA activity. JNK was present in immunocomplexes of PKAc, and PKAc phosphorylated JNK in vitro. Presence of p38 kinase, however, was not prominent in immunocomplexes of PKAc. Our data suggest that JNK is a target point of negative regulation by PKAc in the JNK signaling pathway.

• Proceedings of the PSK Conference
• /
• 2002.10a
• /
• pp.269.1-269.1
• /
• 2002

MPP$\^$＋/ is known to be a neurotoxic substance that induces the degeneration of dopaminergic neurons and Parkinson-like syndrome. Incubation with MPP$\^$＋/ induced the expression of heme oxygenase-l (HO-1) in PC-12 cells and HO-1 revealed a protective effect against MPP$\^$＋/ -induced cytotoxicity. In this study. we tested the effect of pre-conditioning on the MPP$\^$＋/-induced cytotoxicity. The PC-12 cells were incubated with MPP$\^$＋/ for 3 hrs. and then after 12 hrs the cells were exposed to several concentration of MPP$\^$＋/. (omitted)

• Environmental Mutagens and Carcinogens
• /
• v.24 no.3
• /
• pp.128-136
• /
• 2004

CYP1A1 is known to be inducible by xenobiotic compouds such as polyciclic aromatic hydrocarbons(PAHs) and 2,3,7,8-tetrachloro-dibenzo-p-dioxin(TCDD). These chemicals have been identified worldwide and can have a significant impact on the human health and well being of human and wildlife. Given these issues, the detection and quantification of these chemicals in biological, environmental and food samples is important. First, we investigated the effect of on CYP1A1 promoter activity, 7-ethoxyresorufin-O-deethylase(EROD) activity and CYP1A1 mRNA expression induced by benzo(k)fluoranthene(B(k)F) in MCF-7 cells. We found that B(k)F significantly up-regulates the level of CYP1A1 prompter activity, EROD and CYP1A1 mRNA. When cells were treated with genistein, it was not changed that EROD and CYP1A1 mRNA, compared to that of control. However, genistein inhibited the B(k)F-induced CYP1A1 promoter activity and mRNA level at high concentration. Furthermore, in this study, effects of HDAC(histone deacetvlase) inhibitors on human prostate cancer cells proliferation were examined. HC-toxin, SAHA and TSA inhibited cell proliferation in PC3 cells. A novel HDAC inhibitor, IN2001 also suppressed the growth of PC3 cells. And IN2001 and SAHA increased S phase and G2/M phase at 12 hrs treatment but cells were arrested G0/G1 phase at 45 hrs treatment. The HC-toxin treatment for 24 hrs and 48 hrs increased G0/G1 at low concentration ($0.1\mu\textrm{m}$) but increased G2/M at more than concentration of $1\mu\textrm{m}$. TSA increased G2/M phase. These findings height the possbility of developing HDAC inhibitors as potential anticancer therapeutic agents for the treatment of prostate cancer.

• Journal of Oriental Neuropsychiatry
• /
• v.13 no.1
• /
• pp.79-115
• /
• 2002

This research investigates the effect of the Crataegus pinnatifida BGE. var. major N.E. BR(CPVM) on Alzheimer's disease. Specifically, the effects of the DYHT extract on (1) $IL-1{\beta}$, IL-6, amyloid precursor proteins(APP), acetylcholinesterase(AChE), and glial fibrillary acidic protein(GFAP) mRNA of PC-12 cells treated with CTI05; (2) the AChE activity and the APP production of PC-12 cell treated with CT105; (3) the behavior; and (4) expression of $IL-1{\beta}$, $TNF-{\alpha}$, reactive oxygen species(ROS), nitrite oxide(NO); and (5) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with CT105 were investigated. The results are as follow. 1. The CPVM extract suppressed the expression of $IL-1{\beta}$, IL-6, APP, AChE, and GFAP mRNA in PC-12 cells treated with CT105. 2. The CPVM extract suppressed the AChE activity and the production of APP significantly in PC-12 cells treated with CT105. 3. The CPVM extract group showed a significant inhibitory effect on the memory deficit for the mice with Alzheimer's disease induced by CT105 in the Morris water maze experiment. 4. The CPVM extract suppressed the over-expression of $IL-1{\beta}$, $TNF-{\alpha}$, ROS and NO in the mice with Alzheimer's disease induced by CT105. 5. The CPVM extract reduced the infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by CT105. These results suggest that the CPVM extract may be effective for the prevention and treatment of Alzheimer's disease.

• Journal of Oriental Neuropsychiatry
• /
• v.17 no.1
• /
• pp.59-78
• /
• 2006

Objective : This research investigates the effect of the CMT and SCMT on Alzheimer's disease. Methods : The effects of the CMT and SCMT on (1) amyloid precursor proteins(APP), acetylcholinesterase(AChE) mRNA of PC-12 cells treated with CT-105; (2) the AChE activity and the APP production of PC-12 cell treated with CT-105; (3) the behavior; (4) expression of $IL-1{\beta}$, $TNF-{\alpha}$, MDA; (5) the infarction area of the hippocampus in Alzheimer's disease mice induced with CT105 & ${\beta}A$ were investigated Rresults : 1. The CMT and SCMT suppressed the expression of APP, AChE mRNA in PC-12 cells treated with CT-105 2. The CMT and SCMT suppressed the AChE activity, and the production of APP significantly in PC-12 cells treated with CT-105. 3. For the CMT and SCMT group a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}A$ in the Morris water maze experiment, which measured stop-through latency, and distance movement-through latency 4. The CMT and SCMT suppressed the over-expression of $IL-1{\beta}$, $TNF-{\alpha}$, MDA in the mice with Alzheimer's disease induced by ${\beta}A$. 5. The CMT and SCMT reduced the infarction area of hippocampus with Alzheimer's disease induced by ${\beta}A$. Conclusions : These results suggest that the CMT and SCMT may be effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the CMT and SCMT for Alzheimer's disease is suggested for future research.

• The Korea Journal of Herbology
• /
• v.23 no.3
• /
• pp.163-173
• /
• 2008

Objectives : Imyosan (IMS), a drug preparation comprised of Phellodendri Cortex (PC) and Atractylodis Rhizoma (AR), is commonly used as a traditional herbal medicine in Korea and China for the treatment of various inflammatory diseases. However, little is known about the effect of IMS and its component herbs on inflammatory mediators in RAW 264.7 cells. Therefore, in this study, methanol extracts of IMS and its component herbs were examined to determine if they inhibited inflammatory effects in RAW 264.7 cells. Methods : Cytotoxic activity of IJHT and its components on RAW 264.7 cells was using 5-(3-carboxymethoxyphenyl)-2H-tetrazolium inner salt (MTS) assay. The nitric oxide (NO) production was measured by Griess reagent system. And proinflammatory cytokines were measured by ELISA kit. The levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression were detected by western blot. Results : Methanol extract of IMS and its component herbs were significantly reduced iNOS and COX-2 expression as well as NO, PGE2, $IL-1{\beta}$ and IL-6 production in RAW 264.7 cells. Conclusions : The results of this study indicated that the anti-inflammatory effect of Imyosan extract is more potent than that of extracts of its component herbs in macrophages.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
• /
• v.15 no.2
• /
• pp.104-117
• /
• 2002

Objective : The aim of this study was to investigate the skin-whitening effect of Kakamseosiokyong-san Method : We investigated that the extracts of Kakamseosiokyong-san inhibit activity of tyrosinase, the enzyme which converts 3-(3,4-dihydroxyphenyl)alanine to dopachrom in the biosynthetic process of melanin. the UV absorbance of the extracts in the UV - A region and UV - B region was measured by UV scanning. the effect of extracts on cell viability and melanin production in cultured B16 mouse melanoma cells was measured, and cytoprotective effects of extracts on PC12 cells injured by hydrogen peroxide was measured by MTT assay Results: The extracts of Kakamseosiokyong-san inhibited activity of tyrosinase. The extracts not only showed inhibitory effects on melanin production in cultured B16 mouse melanoma cells, but also exhibited cytoprotective effects on PC12 cells injured by hydrogen peroxide, but did not showed an absorbance in the UV - A region and UV - B region. Conclusion: These results suggest that Kakamseosiokyong-san inhibit melanin biosynthesis which is involved in hyperpigmentation and could be used as a whitening agent for the skin.

• Journal of Oriental Neuropsychiatry
• /
• v.15 no.2
• /
• pp.119-139
• /
• 2004

This research investigates the effect of the Hibiscus syriacus(HSS) on Alzheimer's disease. Specifically, the effects of the HSS extract on (1) $IL-1{\beta}$, IL-6, and $TNF-{\alpha}$ mRNA of PC-12 cells treated with LPS; (2) amyloid precursor proteins(APP), acetylcholinesterase(AChE), and glial fibrillary acidic protein(GFAP) mRNA of PC-12 cells treated with CT-105; (3) the AChE activity and the APP production of PC-12 cell treated with CT-105; (4) the behavior; (4) expression of $IL-1{\beta}$, $TNF-{\alpha}$, $IL-1{\beta}$ mRNA, $TNF-{\alpha}$ mRNA, and reactive oxygen species(ROS); (5) the infarction area of the hippocampus, and brain tissue injury in Alzheimer's diseased mice induced with ${\beta}A$ were investigated. The results were summarized below ; 1. The HSS extract suppressed the expression of $IL-1{\beta}$, IL-6 and $TNF-{\alpha}$ mRNA in THP-l cells treated with LPS. 2. The HSS extract suppressed the expression of APP, AChE, and GFAP mRNA in PC-12 cells treated with CT-105. 3. The HSS extract suppressed the AChE activity, and the production of APP significantly in PC-12 cells treated with CT-105. 4. For the HSS extract group a significant inhibitory effect on the memory deficit was shown for the mice with Alzheimer's disease induced by ${\beta}A$ in the Morris water maze experiment, which measured stop-through latency, and distance movement-through latency. 5. The HSS extract suppressed the over-expression of $IL-1{\beta}$, $TNF-{\alpha}$, $IL-1{\beta}$ and $TNF-{\alpha}$ mRNA, CD68/GFAP, ROS in the mice with Alzheimer's disease induced by ${\beta}A$. 6. The HSS extract reduced the infarction area of hippocampus, and controlled the injury of brain tissue in the mice with Alzheimer's disease induced by ${\beta}A$. These results suggest that the HSS extract may be effective for the prevention and treatment of Alzheimer's disease. Investigation into the clinical use of the HSS extract for Alzheimer's disease is suggested for future research.