• Title/Summary/Keyword: Pretreatment effect

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Control of Parturition Time on Pig I. Effect of Parasympathetic Nerve and Cholinergic Agonist on Uterine Smooth Muscle Motility (돼지 분만 시기의 조절에 관하여 I. 자궁 평활근의 운동성에 대한 부교감 신경과 Cholinergic Agonist의 영향)

  • 박상은;황보원;변유성;조광제
    • Korean Journal of Veterinary Service
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    • v.17 no.3
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    • pp.247-254
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    • 1994
  • To elucidate the action of the cholinergic nerve on the isolated uterine smooth muscle of the pig, effects of electrical transmural nerve stimulation and acetylcholine were investigated on the pretreatment of the physostigmine ; cholinestrase inhibitor and atropine ; cholinergic receptor blocker from physiograph. 1. The contractile response induced by acetylcholine was responsed in the concentration of 10^{-8}$ M at first and the maximum contractility was concentration of $10^{-6}$ M. 2. The contractile response induced by electrical transmural nerve stimulation(20 V, 0.5 Msec, 20 sec) was the frequency(2-64 Hz) -dependent manner. 3. The contractile response induced by acetylcholine was completely blocked by the pretreatment with cholinergic receptor blocker, atropine and was increased by the pretrement of cholinestrase inhibitor, physostigmine. 4. The contractile response induced by electrical transmural nerve stimulation was completely blocked by the pretreatment with cholinergic receptor blocker, atropine, and was increased by the pretretment of cholinestrase inhibitor, physostigmine. These findings suggest that it was powerful excitatory action by cholinergic nerve on uterine smooth muscle of the pig.

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Variation of Oak Kraft Pulp Properties by Xylanase Treatment in C/D, P and Z Stage (C/D, P 및 Z단계 표백시 Xylanase처리에 의한 펄프성질의 변화)

  • Kim, Dong-Ho;Paik, Ki-Hyon
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.2
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    • pp.100-109
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    • 1997
  • The objectives of this study was to decrease pollutions of bleaching effluent and was to enhanced brightness of non-chlorine bleached pulps by xylanase treatments. Xylanase cloned Esherichacoli(E. coli) capable of each of endo, exo-xylanase and acetyl-esterase were obtained from Bacillus stearothermophillus. These xylanase was maintained high activity in alkali and high temperature. Especially endo-xylanase would be more active in $60^{\circ}C$ and pH 11. Xylanase pretreatment(X) of unbleached pulp increased brightness, and decreased the degree of delignification. The degree of increase in brightness of pulp due to xylanase pretreatment was similar to non-enzyme treated pulp, regardless of the amount of enzyme added. Therefore, the addition of xylanase of 2 unit was recommended when considering costs of enzyme. The pulp bleached XO sequence had higher brightness and lower Kappa no, than O bleached pulp, while pulp bleached XP sequence had similar brightness and Kappa no. with P bleached pulp. In XOC/D, XOZ and XOP bleaching sequences, brightness and degree of delignification were improved. The C/D and Z stage bleached pulp was good effect on rate of raise in brightness and Kappa no., but P stage bleached pulp had similar level in non-enzyme treated bleaching sequence.

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Protective Effects of Ukyium(우귀음, Yougui-yin) in Zinc-induced Apoptosis of C6 Glial Cells (우귀음이 Zinc에 의한 신경교세포의 고사(Apoptosis)에 미치는 영향)

  • 이영구;문병순
    • The Journal of Korean Medicine
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    • v.22 no.3
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    • pp.63-73
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    • 2001
  • Objectives : The objective of the current study is to determine the protective effect of Ukyium(Yougui-yin) on the apoptosis induced by zinc. Methods : Zinc is known to generate reactive oxygen species (ROS), including superoxide anion ($O_2$) and hydrogen peroxide ($H_2O_2$), which eventually contribute to cytotoxicity in a variety of cell types. We investigated the viablity of cells, $H_2O_2$ generation, chromatin condensation and nuclear fragmentation in Hoechst dye staining and $IkB-{\alpha}$ degradation in C6 glial cells of $ZnCl_2$ between pretreatment- and not pretreatment-group with Ukyium. The former methods were researched by Time- and Dose-dependent manners. Results : We demonstrated that pretreatment with Ukyium prevented zinc-induced cell death of C6 glial cells and apoptotic characteristics including chromatin condensation and nuclear fragmentation. Ukyium also prevented $H_2O_2-induced$ cell death. We further confirmed that Ukyium decreased zinc-induced generation of $H_2O_2$ and inhibited degradation of $IkB-{\alpha}$ by zinc in C6 glial ceHs. Conclusions : These data indicated that Ukyium (Yougui-yin) prevents zinc-induced apoptotic death of C6 glial cells via inhibition of ROS generation, such as $H_2O_2$ as well as inhibition of $IkB-{\alpha}$ degradation.

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Conversion of Methanol to Hydrocarbons over Heteropoly Acids(II) (헤테로폴리산 촉매에 의한 탄화수소로의 메탄올 전환반응(II))

  • Hong, Seong-Soo;Lim, Ki-Chul;Lee, Ho-In
    • Applied Chemistry for Engineering
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    • v.4 no.2
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    • pp.335-341
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    • 1993
  • In the conversion of methanol, the effect of acide property of heteropoly compounds on the catalytic activity was investigated. The pretreatment of Cu-exchanged 12-tungstophosphoric acid with hydrogen enhanced both the selectivity for propane and the conversion of methanol, and the pretreatment of Al-exchanged 12-tungstophosphoric acid with water enhanced the acid strength of the catalyst. The water added into the reactant decreased the conversion of methanol, while the pretreatment temperature did not affect it but the propylene/propane ratio. Various partially-substituted Al salts of 12-tungstophosphoric acid showed different catalytic activities depending on the degree of Al-substitution.

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Neuroprotective effects of vitamin C (비타민 C의 신경 보호 효과)

  • Sim, In-Seop;Lee, Kyeong-Hui;Kim, Eun-Jin;Cha, Myeong-Hun;Kim, Eun-Jeong;Kim, Ga-Min;Kim, Hyeong-A;Lee, Bae-Hwan
    • Proceedings of the Korean Society for Emotion and Sensibility Conference
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    • 2008.10a
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    • pp.147-150
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    • 2008
  • Vitamin C ascorbic acid (AA) and dehydroascorbic acid (DHA) as an antioxidant have been shown to have protective effects in experimental neurological disorder models such as stroke, ischemia, and epileptic seizures. The present study was conducted to examine the protective effect of AA and DHA on Kainic acid (KA) neurotoxicity using organotypic hippocampal slice cultures (OHSC). After 12h KA treatment, significant delayed neuronal death was detected in CA3 region, but not in CA1. Intermediate dose of AA and DHA pretreatment significantly prevented cell death and inhibit ROS level, mitochondrial dysfunction and capase-3 activation in CA3 region. In the case of low or high dose, however, AA or DHA pretreatment were not effective. These data suggest that both AA and DHA pretreatment have neuroprotective effects on KA-induced neuronal injury depending on the concentration, by means of inhibition of ROS generation, mitochondrial dysfunction, and caspase-dependent apoptotic pathway.

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Control of Parturition Time on Pig;IV. Effect of ATP on Uterine Smooth Muscle Motility (돼지 분만 시기의 조절에 관하여;IV. 자궁 평활근의 운동성에 대한 APT의 영향)

  • 박상은;황보원;변유성;조광제
    • Korean Journal of Veterinary Service
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    • v.19 no.2
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    • pp.154-162
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    • 1996
  • The effcets of adenosine 5'-triphosphate(ATP) were investigated on the uterine smooth muscle motility in the pig. The results were summarized as follows: 1. The effects of the porcine uterine smooth muscle and the contractile responses increased between the concentration of ATP $10^{-5}$ and $10^{-3}$ M with a dose-dependent manner. 2. The contractile response induced by ATP($10^{-4}$ M) was not blocked by pretreatment with cholinergic receptor blocker, atropine ($10^{-6}$ M) 3. The contractile response induced by ATP ($10^{-4}$ M) was not blocked by pretreatment with $\alpha$ -adrenergic receptor blocker, phentolamine(10$^{-6}$ M) and ${\beta}$-adrenergic blocker, propranolol ($10^{-6}$ M). 4. The contractile response induced by ATP($10^{-4}$ M) was not appeared in 4Ca^{++}$ -free medium. As the concentration of $Ca^{++}$ in $Ca^{++}$ -free medium was increased, the contractile response induced by ATP ($10^{-4}$ M) was enhenced but was completely inhibited by pretreatment with $Ca^{++}$ -channel blocker, papaverine($10^{-6}$ M) or verapamil($10^{-6}$ M). From these results, it was conclued that the effects of ATP were the contraction mediated by purinergic receptor in uterine smooth muscle of pig.

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Drug Interaction between Flavone and Paclitaxel in Rats (프라본과 파크리탁셀과의 약물상호작용)

  • 최준식;이진환
    • YAKHAK HOEJI
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    • v.47 no.2
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    • pp.98-103
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    • 2003
  • The purpose of this study was to investigate the effect of flavone (20 mg/kg) on the pharmacokinetic parameters and the bioavailability of paclitaxel (40 mg/kg) orally coadministered in rats. The plasma concentration of paclitaxel in combination with flavone was increased significantly (coadministration p<0.05, pretreatment p<0.0l) compared to that of control. Area under the plasma concentration-time curve (AVC) of paclitaxel with flavone was significantly (coadministration p<0.05, pretreatment p<0.0l) higher than that of control. Peak concentration (Cmax) of paclitaxel with flavone were significantly increased (coadministration p<0.05, pretreatment p<0.01) compared to that of control. Time to peak concentration (Tmax) of paclitaxel with flavone decreased significantly (p<0.05) than that of control. The total body clearance (CLt) and elimination rate constant ($\beta$) of paclitaxel with flavone were significantly reduced (p<0.05) compared to those of control. Half-life (t$_{1}$2/) of paclitaxel with flavone was significantly prolonged (p<0.05) compared to that of control. Based on these results, it might be concluded that flavone may enhance bioavailability of paclitaxel through the inhibition of cytochrome P450 and P-glycoprotein, which are engaged in paclitaxel absorption and metabolism in liver and gastrogintestinal mucosa, respectively.

Effects of ECP (exocellular polymers) Changes to the Dewaterability and Settlability of Wastewater Sludge Pretreated by Acid and Ultrasonic (하수슬러지의 산과 초음파 처리에 따른 ECP(exocellular polymers)의 거동이 탈수성과 침강성에 미치는 영향)

  • Hwang, Sun-Jin;Jeong, Kyu-Ho;Whang, Gye-Dae
    • Journal of Korean Society of Water and Wastewater
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    • v.16 no.6
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    • pp.733-740
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    • 2002
  • The effects on dewaterability and settlability of wastewater sludge according to acid and ultrasonic pretreatment which was expected to change ECP (exocellular polymers) compounds in the sludge and bulk solution was investigated. Though ECP which attached to the sludge could stimulate coagulation of sludge particles by bridging effect, but ECP in the bulk solution deteriorated dewaterability and settlability of the sludge on the contrary. That is as the pH of the solution was decreased to 3 gradually by acid treatment, proportionally ECP in the bulk solution was attached to the sludge flocs and resulted in improvement of dewaterability and settlability of the sludge. In case of ultrasonic pretreatment, with proportional to the intensity and duration of ultrasonic application, ECP was detached and extracted from sludge flocs and these phenomena deteriorated dewaterability and settlability. Also because of the increasement of minute sludge particles according to ultrasonic, dewaterability became so much the worse.

Protective and Therapeutic Effects of Malloti Cortex Extract on Carbon Tetrachloride- and Galactosamine-induced Hepatotoxicity in Rats (예덕나무피엑스의 사염화탄소 및 갈락토사민 유발 간독성에 대한 보호 및 치료효과)

  • 임화경;김학성;최홍석;최종원
    • Biomolecules & Therapeutics
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    • v.7 no.1
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    • pp.35-43
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    • 1999
  • Hepatoprotective effects of Malloti cortex extract (MCE) from Mallotus japonicus against the carbon tetrachloride (CCl$_{4}$) and galactosamine (GalN) were investigated. Whereas serum aspartate aminotransferase and alanine aminotransferase levels were markedly elevated after CCl$_{4}$ and GalN administration, pretreatment and posttreatment with MCE before and after the injection of CCl$_{4}$ and GalN resulted in decreases in elevated serum aminotransferase activities. Whereas CCl$_{4}$ and GalN treatment caused 3~7 fold increases in sorbitol dehydrogenase and ${\gamma}$-glutamyltransferase activities, pretreatment and posttreatment with MCE resulted in the blocking of CCl$_{4}$ and GalN-induced liver toxicity. The hepatoprotective effect of MCE was in part due to MCE-induced elevation of hepatic glutathione levels. Pretreatment and posttreatment with MCE also reduced increased lipid peroxidation induced by CCl$_{4}$ and GalN. These results suggest that MCE may be useful for the prevention and therapy of hepatotoxic pathogenesis. It is presumed that protective and therapeutic effects of MCE due to be inducible glutathione S-transferase and glutathione reductase activities, involving in glutathione-medicated detoxication and maintainment of glutathione content, respectively.

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Protective Role of Corticosterone against Hydrogen Peroxide-Induced Neuronal Cell Death in SH-SY5Y Cells

  • Lee, Chan;Jang, Jung-Hee;Park, Gyu Hwan
    • Biomolecules & Therapeutics
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    • v.30 no.6
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    • pp.570-575
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    • 2022
  • Stress breaks body balance, which can cause diverse physiological disorders and worsen preexisting diseases. However, recent studies have reported that controllable stress and overcoming from stress reinforce resilience to resist against more intense stress afterwards. In this study, we investigated the protective effect of corticosterone (CORT), a representative stress hormone against hydrogen peroxide (H2O2)-induced neuronal cell death and its underlying molecular mechanism in SH-SY5Y cells, a human neuroblastoma cell line. The decreased cell viability by H2O2 was effectively restored by the pretreatment with low concentration of CORT (0.03 μM for 72 h) in the cells. H2O2-increased expression of apoptotic markers such as PUMA and Bim was decreased by CORT pretreatment. Furthermore, pretreatment of CORT attenuated H2O2-mediated oxidative damages by upregulation of antioxidant enzymes via activation of nuclear factor erythroid 2-related factor 2 (Nrf2). These findings suggest that low concentration of CORT with eustressed condition enhances intracellular self-defense against H2O2-mediated oxidative cell death, suggesting a role of low concentration of CORT as one of key molecules for resilience and neuronal cell survival.