• Journal of Korean Society on Water Environment
• /
• v.26 no.4
• /
• pp.681-686
• /
• 2010

Two different MFC designs were evaluated in batch mode: single compartment combined membrane-electrodes (SCME) design and twin-compartment brush-type anode electrodes (TBE) design (single chamber with two air cathodes and brush anodes at each side of the reactor). In SCME MFC, carbon anode and cathode electrodes were assembled with a proton exchange membrane (PEM). TBE MFC was consisted of brush-type anode and carbon cloth cathode electrodes without the PEM. A brush-type anode was fabricated with carbon fibers and was placed close to the cathode electrode to reduce the internal resistance. Substrates used in this study were glucose, leachate from cattle manure, or sucrose at different concentrations with phosphate buffer solution (PBS) of 200 mM to increase the conductivity thereby reduce the internal resistance. Hydrogen generating bacteria (HGB) were only inoculated in TBE MFC. The peak power densities ($P_{peak}$) produced from the SCME systems fed with glucose and leachate were 18.8 and $28.7mW/m^2$ at external loads of 1000 ohms, respectively. And the $P_{peak}$ produced from TBE MFC were 40.1 and $18.3mW/m^2$ at sucrose concentration of 5 g/L and external loads of 470 ohms, with a mediator (2-hydroxy-1, 4-naphthoquinone) and without the mediator, respectively. The maximum power density ($P_{max}$) produced from mediator present TBE MFC was $115.3mW/m^2$ at 47 ohms of an external resistor.

• Korean Journal of Weed Science
• /
• v.2 no.1
• /
• pp.31-40
• /
• 1982

For the effective control of weeds in mechanically transplanted paddy field weeding effects of naproanide ${\alpha}$-(${\beta}$-naphthoxy) propion anilide], pyrazolate [4-2, 4-dichlorobenzoyl)-1, 3-dimethyl pyrazol-5-yl-p-tolune sulphanate], chlormethoxynil (2, 4-dichloro-phenyl-4-nitro-3-methoxy phenyl ether), SL-49 [1-3dimethyl-4(2, 4dichlorobenzoyl)-5-phenacyloxy pyrazole], ACN (3-chloro-2-amino-l, 4-naphthoquinone) either alone or in combination with butachlor (2-chlor-2, 6-diethyl-N-buthoxymethyl acetanilide) were compared. Pyrazolate and SL-49 were most effective for the control of Sagittaria pygmaea MIQ. and Potomogeton distinctus A. BENN. including most annual weeds. Weeding effect of butachlor alone was very high for annuals, good for Cyperus serotinus ROTTB. and poor for S. pygmaea and P. distinctus. But the weeding effect of the combination of butachlor and pyrazolate was stronger than that of butachlor alone and therefore this mixture was effective for S. pygmaea, P. distinctus and C. serotinus including all the annual weeds. The combination of butachlor and SL-49 showed the same tendency as the combination of butachlor and pyrazolate. Naproanilide was not effective for the control of Echinochlor crusgalli P. BEAUV and less effective for Monochoria vaginalis PRESL, but excellent for S. pygmaea. By mixing butachlor with naproanilide weeding, spectrum for annuals and S. pygmaea was much increased by that for P. distinctus and C. serotinus was not satisfactory. ACN was not satisfactory for the control of all the tested weeds but the weeding effect was increased in general by mixing with butachlor. Chlormethoxynil was excellent for the control of annual weeds but it has no effect on C. serotinus, S. pygmaea and P. distinctus showing some initial controling effect but these weeds regrew afterwards. The weeding activity of ACN increased in combination with butachlor and the residual activity was stronger than that of ACN alone. A light crop injury was found at the initial period after treatments in all treated plots. The yield from all treated plots except those from plots treated with ACN, butachlor and naproanilide were not significantly different from the band weeded plot.

• Journal of Applied Biological Chemistry
• /
• v.52 no.4
• /
• pp.221-225
• /
• 2009

Lithospermum erythrorhizon has been known well as one of traditional medicine for fever reduction, detoxication, and blood circulation improvement. This study was carried out to isolate biological active compounds from roots of Lithospermum erythrorhizon and to investigate their low density lipoprotein (LDL) antioxidant and anticancer activities. The hexane extract of Lithospermi Radix has been separated on silica gel chromatography and a naphthoquinone pigment compound 1 has been isolated. The structure of the compound 1 has been identified by spectroscopic technique, including MS and NMR, as acetylshikonin (1). Acetylshikonin showed significantly inhibitory activity on $Cu^{2+}$-induced human LDL oxidation with $IC_{50}$ value of $8.8\;{\mu}M$ and obvious anticancer effect by inhibiting farnesyl:protein transferase (FPTase) activity with $IC_{50}$ value of $23\;{\mu}M$, which suggested that acetylshikonin might be useful for the treatment of atherosclerosis and cancer.

• The Korean Journal of Physiology and Pharmacology
• /
• v.17 no.3
• /
• pp.203-208
• /
• 2013

As the abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a critical role in the development of atherosclerosis and vascular restenosis, a candidate drug with antiproliferative properties is needed. We investigated the antiproliferative action and underlying mechanism of a newly synthesized naphthoquinone derivative, 5,8-dimethoxy-2-nonylamino-naphthalene-1,4-dione (2-nonylamino-DMNQ), using VSMCs treated with platelet-derived growth factor (PDGF). 2-Nonylamino-DMNQ inhibited proliferation and cell number of VSMCs induced by PDGF, but not epidermal growth factor (EGF), in a concentration-dependent manner without any cytotoxicity. This derivative suppressed PDGF-induced $[^3H]$-thymidine incorporation, cell cycle progression from $G_0/G_1$ to S phase, and the phosphorylation of phosphor-retinoblastoma protein (pRb) as well as the expression of cyclin E/D, cyclin-dependent kinase (CDK) 2/4, and proliferating cell nuclear antigen (PCNA). Importantly, 2-nonylamino-DMNQ inhibited the phosphorylation of PDGF receptor${\beta}$(PDGF-$R{\beta}$) enhanced by PDGF at $Tyr^{579}$, $Tyr^{716}$, $Tyr^{751}$, and $Tyr^{1021}$ residues. Subsequently, 2-nonylamino-DMNQ inhibited PDGF-induced phosphorylation of STAT3, ERK1/2, Akt, and $PLC{\gamma}1$. Therefore, our results indicate that 2-nonylamino-DMNQ inhibits PDGF-induced VSMC proliferation by blocking PDGF-$R{\beta}$ autophosphorylation, and subsequently PDGF-$R{\beta}$-mediated downstream signaling pathways.

• Korean Journal of Weed Science
• /
• v.2 no.1
• /
• pp.41-46
• /
• 1982

Herbicidal effectivity on perennial paddy weeds such as Sagittaria pygmaea Miq. and Eleocharis kuroguwai Ohwi was evaluated. Herbicides used were butachlor [2-chloro-2, 6-dietyl-N(butoxymethyl)-acetanilide], benthiocarb [S-(4-chlorobenzy)-N, N-diethyl-thiocarbamate], molinate (S-ethyhexahyaro-l-Hazpine-carbothiate], SW-751, Chlormethoxynil (2.4-dichlorophenyl-3-methoxy-4-nitrophenyl-ether), CNP (2.4.6-trichlorophenyl-4-nitrophenylether),oxadiazon [2-tertbutyl-4-(2.4-dichloro-S-isopropoxyphenyl)-5-OXO-1.3.4-Oxadiazoline], dinuron [1-dimethyl-benthyl)-3-pheratrylurea], bentazon [3-isopropyl-IH-2.1.3-benzothiadiazine-(4)3H-one-2.2-dioxide], ACN (3-chloro-2-amino-l.4-naphthoquinone), MCPB [4-(2-methyl-4chlorophenoxy), butyric acid], 2.4-D (sodium 2.4-dichlorophenoxy acetic acid), MCP) sodium 2-methyl-4-chlorophenoxy acetic acid), SST-5, TH 63. Graszin D (Bentazon/2.4-D) and Graszin M (Bentazon/MCP) Herbicidal effectivity was divided into three types. Type I was the complete control both leaf and tuber, and SW-751 was belonged to this type. Type II was the partial control that exhibit complete control within certain period after herbicide application. After a certain period, however, the lateral bud have the germinability and grow normally, there after. Chloromethoxynil, CNP, ACN, and Oxadiazon were belonged to this group. Type III was no control at all. For E. kuroguwai, application of CNP, Chloromethoxnil, Oxadiazon and SW-751 gave good control in the early stage shile 2.4-D, MCP, bentazon and glaszin-D controlled well the intermediate stage application. Based on this results, E. kuroguwai can be controlled by herbicide application either in the early stage or in the intermediate stage.

• Proceedings of the Korean Biophysical Society Conference
• /
• 2003.06a
• /
• pp.80-80
• /
• 2003

${\beta}$-lapachone(${\beta}$-Lap), a natural o-naphthoquinone, presents in the bark of the Lapacho tree. ${\beta}$-Lap is cytotoxic against a variety of human cancer cells and it potentiates the anti-tumor effect of Taxol. In addition, ${\beta}$-Lap has been reported to radiosensitize cancer cells by inhibiting the repair of radiation-induced DNA damage.In the present study, we investigated the cytotoxicity of ${\beta}$-Lap against RKO human colorectal cancer cells as well as the combined effect of ${\beta}$-LaP and ionizing radiation. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h killed almost 90％ of the clonogenic cells. An incubation of RKO cells with 5 ${\mu}$M of ${\beta}$-Lap for 4 h or longer also caused massive apoptosis. Unlike other cytotoxic agents, ${\beta}$-Lap did not increase the expression of p53 and p21 and it suppressed the NFkB expression. The expression of Caspase 9 and 3 was minimally altered by ${\beta}$-Lap. Radiation and ${\beta}$-Lap acted synergistically in inducing clonogenic cell death and apoptosis in RKO cells when ${\beta}$-Lap treatment was applied after but not before the radiation exposure of the cells. Interestingly, a 4 h treatment with 5 ${\mu}$M of ${\beta}$-Lap starting 5 h after irradiation was as effective as that starting immediately after irradiation. The mechanisms of ${\beta}$-Lap-induced cell killing is controversial but a recent hypothesis is that ${\beta}$-Lap is activated by NAD(P)H: quinone-onidoreductase (NQO1) in the cells followed by an elevation of cytosolic Ca$\^$2+/ level and activation of proteases leading to apoptosis. It has been reported that NQO1 level in cells is markedly up-regulated for longer than 10 h after irradiation. Indeed, using immunological staining of NQO1, we observed a significant elevation of NQO1 expression in RKO cells 5h after 2-4 Gy irradiation. Such a prolonged elevation of NQO1 level after irradiation may be the reasons why the ${\beta}$-Lap treatment applied S h after irradiation was as effective as that applied immediately after irradiation in killing the cells. In view of the fact that the repair of radiation-induced damage is usually completed within 1-2 h after irradiation, it is highly likely that the ${\beta}$-Lap treahment applied 5 h after irradiation could not inhibit the repair of radiation-induced damage. For in vivo study, RKO cells were injected S.C. into the hind-leg of Nu/Nu mice, and allowed to grow to 130 mm3 tumor. The mice were i.p. injected with ${\beta}$-lapachone or saline 2 h after irradiation of tumors with 10 Gy of X-rays. The radiation induced growth delay was increased by 2.4 $\mu\textrm{g}$/g of ${\beta}$-lapachone. Taken together, we may conclude that the synergistic interaction of radiation and ${\beta}$-Lap in killing cancer cells is not due to radiosensitization by ${\beta}$-Lap but to an enhancement of ${\beta}$-Lap cytotoxicity by radiation through an upregulation of NQO1. The fact that NQO1 is elevated in tumors and that radiation causes prolonged increase of the NQO1 expression may be exploited to preferentially kill tumor cells using ${\beta}$-Lap in combination with radiotherapy.