• The Journal of Korean Medicine
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• v.25 no.4
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• pp.61-78
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• 2004

Objective : This study was undertaken to determine whether Gamibaegi-eum (BGU) in vitro and in vivo exerts a beneficial effect against cell injury induced by reactive oxygen species (ROS) in the human intestine. Methods : Effects of BGU in vitro on cell injury were examined using Caco-2 cells, cultured human intestinal cell line. Exposure of cells to H₂O₂ induced increases in the loss of cell viability in a time and dose-dependent fashion. Results : BGU prevented H₂O₂-induced cell death and its effect was dose-dependent over a concentration range of 0.05­1%. H₂O₂-induced cell death was prevented by catalase, the hydrogen peroxide scavenger enzyme, and deferoxamine, the iron chelator. However, the potent antioxidant DPPD did not affect H₂O₂-induced cell death. H₂O₂ increased lipid peroxidation, which was inhibited by BGU and DPPD. H₂O₂ caused DNA damage in a dose-dependent manner, which was prevented by BGU, catalase, and deferoxamine, but not DPPD. BGU restored ATP depletion induced by H₂O₂. BGU inhibited generation of superoxide and H₂O₂ and scavenged directly H₂O₂. Oral administration of mepirizole in vivo at a dose of 200mg/kg resulted in ulcer lesions in the stomach and the proximal duodenum. Pretreatment of BGU(0.1%/kg, orally) and catalase (800Units/kg, i.v.) significantly decreased the size of ulcers. Mepirizole increased lipid peroxidation in the mucosa of the duodenum, suggesting an involvement of ROS. Pretreatment of BGU and catalase significantly inhibited lipid peroxidation induced by mepirizole. Morphological studies showed that mepirizole treatment causes duodenal injury and its effect is prevented by BGU. Conclusion : These results indicate that BGU exerts a protective effect against cell injury in vitro and in vivo through antioxidant action. The present study suggests that BGU may playa therapeutic role in the treatment of human gastrointestinal diseases mediated by ROS.

• Korean Journal of Food Science and Technology
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• v.29 no.2
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• pp.292-301
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• 1997

In drying process, to minimize the quality degradation by improved drying process and pretreatment methods, carrots, cabbages and radishes were dried and rehydrated. Physico-chemical properties of product were analyzed to determine the optimum pretreatment method and drying models were applied to explain drying mechanisms. Microwave, steam and water were used prior to drying as blanching method. In consideration of physical properties, optimum treatment time was decided that microwave was 1 min, steam and water were each 10 min. Control, steam, water, microwave and osmotic dehydration were treated prior to drying as pretreatment individually, osmotic dehydration was lower than the other treatmemt in drying efficiency, but carotene content was higher than the others. The effect continued after rehydration. Ten panelists tested dried and rehydrated carrots. After rehydration, the quality of air dried product with osmotic dehydration was superior to freeze dried without treatment. The fittness of drying models were conducted in order to explain the mechanism of drying each process. Quadratic model was most fittable to explain during drying. However, in rehydration process, no fittable model was found.

• Journal of Physiology & Pathology in Korean Medicine
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• v.27 no.4
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• pp.400-408
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• 2013

This study aimed to investigate the relaxation effects and its underlying mechanisms of Rubus coreanus(RC) extract in contracted rabbit corpus cavernous tissues by phenylephrine(PE) $1{\mu}M$. In order to define the relaxation effects of RC, rabbit corpus cavernous tissues were prepared in $2{\times}2{\times}6mm$ sized strip. The dose-dependent relaxation responses of RC at 0.01-3.0 $mg/m{\ell}$ in contracted strips induced by PE were measured and also observed after endothelial denudation. To analyze the underlying mechanisms of RC-induced relaxation, indomethacin(IM), tetraethylammonium chloride(TEA), $N{\omega}$-nitro-L-arginine (L-NNA), methylene blue(MB) were treated before RC extract infused into precontracted strips induced by PE. To study the effect of RC extract on influx of extracellular $Ca^{2+}$ in corpus cavernous strips, calcium chloride(Ca) 1 mM infused into precontracted strips induced by PE after pretreatment of RC extract in $Ca^{2+}$-free krebs-ringer solution. To investigate cytotoxic activity and nitric oxide(NO) concentration of RC extract on human umbilical vein endothelial cell(HUVEC), cell viability on HUVEC was measured by MTT assay, and NO concentration was measured by Griess reagent system. The cavernous strips were significantly relaxed by RC extract at 1.0 $mg/m{\ell}$, 3.0 $mg/m{\ell}$ and the relaxation responses to RC were inhibited significantly by endothelial disruption. The pretreatment of IM, TEA didn't affect RC extract-induced endothelium-dependent relaxation, but the pretreatment of L-NNA, MB reduced RC extract-induced endothelium-dependent relaxation. When $Ca^{2+}$ was supplied the cavernous strips which were precontracted by PE in a $Ca^{2+}$-free krebs-ringer solution, contraction of strips was increased, but pretreatment of RC inhibited contractile response to $Ca^{2+}$. When RC extract was applicated on HUVEC, NO concentration was increased. Our findings show that RC extract exerts a relaxing effect on corpus cavernosum in part by suppressing influx of extracellular $Ca^{2+}$ through activating the NO-cGMP system.

• Journal of Pharmacopuncture
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• v.19 no.2
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• pp.163-166
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• 2016

Objectives: Quercetin is a flavonoid and an important dietary constituent of fruits and vegetables. In recent years, several pharmacological activities of quercetin, such as its neuroprotective activity and, more specifically, its anti-convulsant effects in animal models of epilepsy, have been reported. This study evaluated the role of quercetin pretreatment on gene expression of ${\gamma}$-amino butyric acid type A ($GABA_A$) receptor beta subunits in kainic acid (KA)-induced seizures in mice. Methods: The animals were divided into four groups: one saline group, one group in which seizures were induced by using KA (10 mg/kg) without quercetin pretreatment and two groups pretreated with quercetin (50 and 100 mg/kg) prior to seizures being induced by using KA. Next, the messenger ribonucleic acid (mRNA) levels of the $GABA_A$ receptor ${\beta}$ subunits in the hippocampus of each animal were assessed at 2 hours and 7 days after KA administration. Quantitative real-time polymerase chain reaction (RT-PCR) assay was used to detect mRNA content in hippocampal tissues. Results: Pretreatments with quercetin at doses of 50 and 100 mg/kg prevented significant increases in the mRNA levels of the ${\beta}_1$ and the ${\beta}_3$ subunits of the $GABA_A$ receptor at 2 hours after KA injection. Pretreatment with quercetin (100 mg/kg) significantly inhibited ${\beta}_1$ and ${\beta}_3$ gene expression in the hippocampus at 7 days after KA injection. But, this inhibitory effect of quercetin at 50 mg/kg on the mRNA levels of the ${\beta}_3$ subunit of the $GABA_A$ receptor was not observed at 7 days after KA administration. Conclusion: These results suggest that quercetin (100 mg/kg) modulates the expression of the $GABA_A$ receptor ${\beta}_1$ and ${\beta}_3$ subunits in the KA model of epilepsy, most likely to prevent compensatory responses. This may be related to the narrow therapeutic dose range for the anticonvulsant activities of quercetin.

• Journal of Yeungnam Medical Science
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• v.9 no.1
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• pp.137-148
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• 1992

The purpose of this study was to evaluate the influence of phenobarbital(PB) on hepatotoxic effect of carbon tetrachloride($CCl_4$) which induces centrilobular necrosis in liver. Rats were injected intraperitoneally $CCl_4$ dissolved in olive oil by a dose of 0.4mg/kg. For change related to PB pretreatment, rats were injected $CCl_4$ 0.4mg/kg after PB pretreatment. The liver samples were taken in 6, 12, 24, 48, 72, and 120 hours after $CCl_4$ and/or FB injection. Extracted liver tissue was examined with light and electron microscopes. The results were sumarized as follows : 1. Light microscopic findings : In $CCl_4$ group, centrilobular necrosis developed from 6 hours after injection, was the most severe in 48 hours, and recovered after 72 hours. In addition to necrosis, fatty change and pale cell change were accompanied. In PB-$CCl_4$ group, necrosis occurred from 6 hours after $CCl_4$ injection and continued to 72 hours, and the degree of necrosis was more severe than that of $CCl_4$ group and pale cell change was decreased. 2. Electron microscopic findings: In $CCl_4$ group, the early principal change was clumping and vesicular dilatation of endoplasmic reticulum. In PB-$CCl_4$ group, the degenerative change of endoplasmic reticulum was aggrevated and the mitochondria also revealed severe degenerative change. According to the results, it was revealed that $CCl_4$ hepatotoxicity primarily began with the damage of endoplasimic reticulum, then damage of other cell organelles and cell necrosis followed, and these cytotoxic effects were aggrevated by PB pretreatment.

• The Korean Journal of Pharmacology
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• v.18 no.2
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• pp.59-67
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• 1982

1) Oxymetazoline, which has been known as an agonist for${\alpha}_1-adrenoceptor$ in various peripheral tissues, caused a pressor response in urethane-anesthetized rabbits when given intra-ventricularly. This pressor response was little affected by pretreatment of rabbits with i.v. guanethidine or chlorisondamine, but it was weakened in rabbits pretreated with either of i.v. phentolamine or guanethidine and chlorisondamine and in guanethidine-pretreated adrenal-ligated rabbits. 2) The pressor to intraventricular oxymetazoline was markedly attenuated by intraventricular pretreatment with prazosin, whereas intraventricular pretreatment with yohimbine or piperoxan did not affect this response. 3) Reserpine-pretreated rabbits also responded with hypertension to intraventricular oxymetazoline, which was markedly diminished by pretreatment with intraventricular prazosin but not affected by yohimbine. 4) Oxymetazoline, given intravenously, produced a pressor response in both whole and spinal rabbits. Intravenous prazosin, phentolamine and yohimbine, in this order, showed greater antagonizing effect to this pressor response. 5) The results indicate that oxymetazoline acts an agonist for ${\alpha}_1-adrenoceptors$ in the rabbit brain participating in the regulation of the blood pressure and in the vasculature of rabbits.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.163-167
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• 2013

In the present study, the effect of intrathecal (i.t.) or intracerebroventricular (i.c.v.) administration with cholera toxin (CTX) on the blood glucose level was examined in ICR mice. The i.t. treatment with CTX alone for 24 h dose-dependently increased the blood glucose level. However, i.c.v. treatment with CTX for 24 h did not affect the blood glucose level. When mice were orally fed with D-glucose (2 g/kg), the blood glucose level reached to a maximum level at 30 min and almost returned to the control level at 120 min after D-glucose feeding. I.c.v. pretreatment with CTX increased the blood glucose level in a potentiative manner, whereas i.t. pretreatment with CTX increased the blood glucose level in an additive manner in a D-glucose fed group. In addition, the blood glucose level was increased in formalin-induced pain animal model. I.c.v. pretreatment with CTX enhanced the blood glucose level in a potentiative manner in formalin-induced pain animal model. On the other hand, i.t. pretreatment with CTX increased the blood glucose level in an additive manner in formalin-induced pain animal model. Our results suggest that CTX administered supraspinally or spinally differentially modulates the regulation of the blood glucose level in D-glucose fed model as well as in formalin-induced pain model.

• 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.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.5
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• pp.621-632
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• 2007

Statement of problem: The failure of adhesion between the resilient denture liner and the denture base is a serious problem in clinic. Purpose: The purpose of this study was to evaluate the effect of denture base resin surface pretreatments (mechanical and/or chemical) on the tensile bond strength between a resilient liner and processed denture resin. Material and method. Acrylic-based resilient liners (Soft liner; GC co., Japan & Coe-Soft; GC America Inc. USA) and silicone-based resilient liners (Mucosoft, Parkell Inc., USA & Dentusil; Bosworth co., USA) were used. Specimens in each soft lining material were divided two groups with or without mechanical pretreatment. Each denture base specimen received 1 of 4 chemical pretreatments including: (1) no treatment, (2) 30-s acetone treatment, (3) 15-s methylene chloride treatment, (4) 180-s methyl methacrylate treatment. All specimens were thermocycled and placed under tension until failure in a universal testing machine. Results: 1. Silicone-based resilient liners exhibited significantly higher tensile bond strengths than acrylic-based resilient liners (P<.05). 2. Grinding the denture base resin improved tensile bond strengths of silicone-based resilient liners, but reduced tensile bond strengths of acrylic-based resilient liners (P<.05). 3. In acrylic-based resilient liners, treating with acetone significantly increased the bond strength of Soft liner and treating with methyl methacrylate significantly increased the bond strength of Coe-Soft (P<.05). However they were not effective compared to silicone-based resilient liner. 4. In silicone-based resilient liners, treating with all chemical etchants significantly increased the bond strength of Mucosoft to denture base, and treating with methylene chloride and methyl methacrylate increased the bond strength of Dentusil to denture base (P<.05). Conclusion: Although chemical and mechanical pretreatments were not effective on tensile bond strength of acrylic-based resilent liner to denture base, treating the denture base resin surface with appropriate chemical etchants after mechanical pretreatment significantly increased the tensile bond strength of silicone-based resilient liner to denture base.

• Korean Chemical Engineering Research
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• v.52 no.1
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• pp.45-51
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• 2014

This is to study the effects of various pretreatment methods of agricultural residue, corn stover, and to compare the feature and pros and cons of each method including dilute sulfuric acid (DSA), soaking in aqueous ammonia (SAA), and ammonia recycle percolation (ARP). In order to convert corn stover to ethanol, various pretreatments followed by simultaneous saccharification and co-fermentation (SSCF) were tested and evaluated in terms of ethanol yield. With 3%, w/w of glucan loading using ARP-, DSA-, and SAA-treated solids, SSCFs using recombinant E. coli strain (ATCC$^{(R)}$ 55124) with commercial enzymes (15 FPU of Spezyme CP/g-glucan and 30 CBU/g-glucan enzyme loading) were tested. In the SSCF tests, 87, 90, and 78% of theoretical maximum ethanol yield were observed using ARP-, DSA-, and SAA-treated solids, respectively, which were 69, 58, and 74% on the basis of total carbohydrates (glucan + xylan) in the untreated corn stover. Ethanol yield of SAA-treated solid was higher than those of ARP- and DSA-treated solids. In addition, SSCF test using treated solids plus pretreated hydrolysate indicated that the DSA-treated hydrolysate showed the strongest inhibition effect on the KO11 strain, whereas the ARP-treated hydrolysate was found to have the second strongest inhibition effect. Bioconversion scheme using SAA pretreatment and SSCF can make the downstream process simple, which is suggested to produce ethanol economically because utilization of hemicellulose in the hydrolysate is not necessary.