• Toxicological Research
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• v.11 no.2
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• pp.273-277
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• 1995

Several metabolic modulators on the generation of carbon monoxide (CO)from dichloromethane (DCM) was examined in adult female rats. It has been known that DCM is converted to CO by cytochrome P-450 or to carbon dioxide $(CO_2)$ by glutathione-dependent metabolic reaction. In rats treated with DCM (3 mmol/kg, ip) only, the carboxyhemoglobin (COHb) level reached a peak of approximately 10% 2 or 3 hr following the treatment. Disulfiram (300 mg/kg, ip) or allylsulfide (200 mg/kg, po), both known as a selective inhibitior for cytochrome P-450 2E1, blocked the increase in COHb concentratlons almost completely suggesting that the metabolic conversion of DCM to CO is mediated by the activity of this specific type of isozyme. YH439 (125 or 250 mg/kg, po), a potential hepatoprotective agent, decreased the COHb elevation as well indicating that this chemical is a potent inhibitor for 2E1. In rats treated with pyrazine (200 mg/kg, ip) 18 hr prior to DCM the peak COHb concentration was decreased by approximately 3 or 4%. However, pretreatment of rats with pyrazine either 24 or 48 hr before DCM increased the peak COHb concentration significantly compared to the rats treated with DCM only. The results in the present study strongly suggest that the generation of CO from DCM depends on the 2E1 activity and that the pharmacological and/or toxicological action of YH439 or pyrazine in animals or human is associated with its effect on this isozyme.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.291-297
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• 1996

The role of cytochrome P-450 2E1 (P450 2E1) in the early phase of alcoholic fatty liver was examined. Female rats were pretreated with either allyl sulfide (200 mg/kg, po), disulfiram (500 mg/kg, po), YH 439 (250 mg/kg, po) or pyrazine (200 mg/kg/day$\times$2 days, ip). Marked changes in carbon tetrachloride-induced hepatotoxicity and caboxyhemoglobin (COHb) elevation due to dichloromethane administration were observed in rats treated with one of the P450 2E1 modulators. A single dose of ethanol (6 g/kg, po) increased the hepatic triglyceride contents approximately 2 fold, which was inhibited completely by YH 439 pretreatment. However, the other P450 2E1 modulators failed to alter the ethanol-induced hepatic triglyceride accumulation. In vitro hepatic microsomal enzyme activity was determined in 4 week old premature and 12 week old adult rats. Aminopyrine-N demethylation was not different, but p-nitrophenol hydroxylation and p-nitroanisole O-demethylation were significantly higher in premature rats. However, no difference in the triglyceride accumulation induced by an intraperitoneal dose of ethanol (3 g/kg) was noted between premature and adult rats. The results suggest that the P450 2E1 activity dose not play an important role in the induction of acute alcoholic fatty liver.

• Journal of environmental and Sanitary engineering
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• v.16 no.1
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• pp.108-116
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• 2001

It is difficult to task to achieve high biological nutrient removal from municipal wastewater because of low organic content. Volatile fatty acids(VFAs) produced from acid fermentation of food wastes can be utilized as external carbon sources for the biological nutrient process. Significant reduction and stabilization of the food wastes can also be obtained from the acid fermentation. The objective of this study is to evaluate characteristics of acid fermentation of the food wastes. Results obtained from the batch experiment of various organic wastes showed that the food wastes had high potential to be used as an external carbon source because of the largest production of the VFAs with low nitrogen and phosphorus content. The fish waste was found to be the next possible organic waste, while the others such as radish cabbage and molasses waste showed high VFAs consumption potential as a results of high nitrogen and phosphorus content. alkaline hydrolysis of the food waste was carried out using NaOH prior to the acid fermentation. As the alkali addition increased, solubilization of the organics as well as TSS reduction increased. However, fraction of soluble COD to total COD became stable after a sharp increase. Alkali addition greater than 0.5g NaOH per g TS resulted in significant increase in pH.

• Archives of Pharmacal Research
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• v.21 no.5
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• pp.508-513
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• 1998

The hepatoprotective effect of DA-9601, a quality-controlled extract of artemisisa asiatica, on liver damage induced by acetaminophen (APAP) and carbon tetrachloride ($CCI_{4}$) was investigated by means of serum-biochemical, hepatic-biochemical, and histopathological examinations. Doses of Da-9601 (10, 30, or 100 mg/kg) were administered intragastrically to each rat on three consecutive days i.e. 48 h, 24 h and 2 h before a single administration of APAP (640 mg/kg, i.p.) or $CCI_{4}$ (2 ml/kg, p.o.). Four h and 24 h after hepatotoxin treatment, the animals were sacrificed for evaluation of liver damage. Pretreatment of Da-9601 reduced the elevation of serum ALT, AST. LDH and histopathological changes such as centrilobular necrosis, vacuolar degeneration and inflammatory cell infiltration dose-dependently. Da-9601 also prevented APAP- and $CCI_{4}$-induced hepatic glutathione (GSH) depletion and $CCI_{4}$-induced increase of hepatic malondialdehyde (MDA), a parameter of lipid peroxidation, in a chemically induced liver injury by complex mechanisms which involve prevention of lipid peroxidation and preservation of hepatic GSH.

• Applied Chemistry for Engineering
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• v.17 no.5
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• pp.465-470
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• 2006

Siloxanes are widely used in industrial processes and consumer products. When landfill gas is used as fuel for gas engines, volatile siloxane in landfill gas causes serious damage to gas engines and pretreatment facilities. In this study, the applicability of various clay minerals was evaluated as the alternative adsorbents of activated carbon. SEM and BET analyses of illite, vermiculite, and activated carbon were performed for comparing those physical properties. Siloxane adsorption capacities of illite and vermiculite were estimated very high to 1.7 g/g illite, 3.8 g/g vermiculite respectively through the adsorption experiments of D5 siloxane.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1862-1864
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• 2005

Carbon nanotubes [CNTs] are grown on TiN-coated Si substrates at $700^{\circ}C$ by inductively coupled plasma-chemical vapor deposition (ICP-CVD). Pre-treatment of Ni catalysts has been performed using an RF magnetron sputtering system. Structural properties and field-emission characteristics of the CNTs grown are analyzed in terms of the RF power applied and the treatment time used in the pre-treatment process. The characterization using various techniques, such as FE-SEM, AFM, and Raman spectroscopy, show that the physical dimension as well as the crystal quality of CNTs are changed by pre-treatment of Ni catalysts. It is also seen that Ni catalysts with proper grain size and uniform surface roughness may produce much better electron emission. The physical reason for all the measured data obtained are discussed to establish the relationship between the structural property and the electron emission characteristic of CNTs.

• Plant Resources
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• v.2 no.1
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• pp.42-48
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• 1999

This study was undertaken to examine the feasibility of black locust (Robinia pseudoacacia) as substrates for several edible mushrooms. For the cultivation of several edible and/or medicinal fungi on black locust, optimum bulk densities, synthetic or semisynthetic additives, natural additives and pretreatment methods were investigated. Fruit body yields of the fungi on various sawdust media composed of different wood species were also analyzed for testing the capability of black locust as a substrate for mushroom production. Mycelial growths decreased proportional when the bulk density increased. The most suitable carbon and nitrogen sources as additives to promote the mycelial growth were sucrose (2%, w/w) and ammonium phosphate (0.2%, w/w) respectively. When corn-powder and beer-waste as natural additives were added to sawdust of black locust showed the significant growth of mycelia. And the optimum mixing ratio was 10:2:1 (sawdust: corn-powder: beer-waste, w/w). Black locust after cold water treatment showed the outstanding mycelial growths. Any significant changes of pH, moisture content (%) and dry-weight losses (%) could not be found among culture substrates (sawdust of black locust, oak and poplar wood) examined before and after harvesting of fruit bodies. Yield of fruit bodies on black locust culture media were comparable with those culture media composed with oak and poplar wood. The present work indicated strongly the potentiality of black locust as raw materials for edible and medicinal mushrooms.

• Membrane Journal
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• v.24 no.1
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• pp.31-38
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• 2014

Rainwater harvesting is a process by which rainwater collected from rooftop or other catchment is purified so that the water can be directly or indirectly used by human beings for beneficial uses. As rainwater is increasingly considered for high quality purposes, membranes have gained an important place in rainwater treatment. It has advantages such as the production of high quality water, small footprint, and affordable energy consumption. Nevertheless, membrane fouling is regarded as a serious problem similar to the cases of water treatment and wastewater reclamation. In this study, we applied microfiltration (MF) membranes for rainwater treatment. In addition, a low pressure ultraviolet (UV) process was also use as a pretreatment to control notonly. To quantify the effect of UV on organic matters, both total organic carbon (TOC) and UV absorbance (UVA) were measured. Moreover, the effect of UV pretreatment on membrane fouling was investigated. Experimental results indicated that the pretreatment of membranes using LPUV was effective to control fouling of MF membranes only when the rainwater was contaminated by algae. This was attributed the reduction and modification of organics after UV treatments. It is likely that the UV/MF process is a promising option for water treatment in decentralized water treatment such as micro water grid systems.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.479-485
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• 2011

Pt-Bi/C catalysts supported on carbon black with various Pt/Bi ratios were synthesized by a reduction method. Chloroplatinic acid hydrate ($H_2PtCl_6{\cdot}xH_2O$) and bismuth (III) nitrate pentahydrate ($Bi(NO_3)_3{\cdot}5H_2O$) were used as precursors for Pt and Bi, respectively. Before loading metal on carbon, heat treatment and pretreatment of carbon black in an acidic solution was conducted to enhance the degree of dispersion. The physical property of the synthesized catalysts was investigated by X-ray diffraction and X-ray photoelectron spectroscopy. The XRD pattern of untreated Pt-Bi/C catalyst showed BiPt and $Bi_2Pt$ peaks in addition to Pt peaks. These results imply that Bi atoms were incorporated into the Pt crystal lattice by Pt-Bi alloy formation. The catalytic activity for methanol oxidation was measured using cyclic voltammetry in a mixture of 0.5 M $H_2SO_4$ and 0.5 M $CH_3OH$ aqueous solution. The addition of proper amount of Bi was found to significantly improve catalytic activity for methanol oxidation. The catalytic activity for methanol oxidation was closely related to the stability between electrode and electrolyte. In order to investigate the stability of catalysts, chronoamperometry analysis was carried out in the same solution at 0.6 V.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.203-207
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• 2008

The present study aimed at assessing the protective effect of water extract from fruit body of the Grifola frondosa (GFW) on carbon tetrachloride ($CCl_4$)-induced hepatotoxicity. Rats orally administered with GFW 0.5, 1.0, 2.0 g/kg for 14 days were treated with $CCl_4$ to induce hepatotoxicity. Pretreatment with GFW remarkably prevented the elevation of serum AST, ALT, ALP, LDH, $\gamma$-GTP, and liver lipid peroxides in $CCl_4$-treated rat and GFW administration in liver injured rats by $CCl_4$ showed significant (p<0.05) protection of liver as evidenced from normal serum enzymes and malondialdehyde (MDA) levels. In the ultrastructural changes, administration of $CCl_4$-induced damage of hepatocytes with vacuolation, a highly damaged endoplasmic reticulum, and degenerating nuclei. However, pre-administration with GFW preserved normal ultrastructure of hepatocytes. These results suggest that GFW had an effect to inhibit $CCl_4$-induced liver injury in rat, and that it could be used as an effective hepatoprotective agent against chemical-induced liver damage.