• Title/Summary/Keyword: isolated maximum point

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Effects of Cyclobuxine D on Drug-Induced Contractions of the Isolated Rat Uterine Muscle and Potassium-Activated Calcium Channels in an Intestinal Smooth Muscle (흰쥐 적출 자궁의 수축 작용과 흰쥐 장관에 있어 칼륨에 의해 활성화되는 칼슘 채널에 대한 Cyclobuxine D의 영향)

  • Kwon, Jun-Tack;Lee, Jong-Hwoa;Park, Young-Hyun;Cho, Byung-Heon;Choi, Kyu-Hong;Kim, Yu-Jae;Kim, Jong-Bae;Kim, Chung-Mok;Kim, Chun-Sook;Cha, Young-Deog;Kim, Young-Suk
    • The Korean Journal of Pharmacology
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    • v.24 no.1
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    • pp.103-109
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    • 1988
  • Cyclobuxine D, extracted from Buxus microphylla var. koreana Nakai, is a steroidal alkaloid. Many pharmacological effects of cyclobuxine D were examined in our Lab. Cyclobuxine D showed a significant bradycardic effect in the rat heart and an inhibitory action on acetylcholine and $Ba^{++}-induced$ contraction of the longitudinal muscle isolated from the rabbit jejunum. In this study, we investigated the effect of cyclobuxine D on the contractile response-elicited by acetylcholine, oxytocin and $Ba^{++}$ in rat uterine. In order to analyse the inhibitory action of cyclobuxine D on the smooth muscle, we examined the inhibitory action of cyclobuxine D against the contractile response of the high potassium-depolarized rat ileum to calcium. Concentration-dependent decrease in the peak tension and duration of the acetylcholine, oxytocin and $Ba^{++}-induced$ contraction in the isolated rat uterus was observed when cyclobuxine D was added to the organ bath. The isolated longitudinal muscle from the rat ileum was immersed calcium-depleted potassium-depolarizing solution. Ten minutes after, 1.8 mM $CaCl_2$ was added to muscle bath and elicited a biphasic increase in muscle tension. Cyclobuxine D $(6.2{\times}10^{-5}\;M)$ produced an appreciable inhibition of both components of the mechanical response. In addition, $3.1{\times}10^{-4}\;M$ cyclobuxine D, introduced at a point when the tonic response had reached its maximum level, caused the muscle to exhibit a rapid lose of tension. Based on these experimental results, we propose the possibility that the inhibitory action of cyclobuxine D on the acetylcholine, oxytocin and $Ba^{++}-induced$ contraction in the isolated rat uterus may be due to blocking potassium-activated calcium channels, voltage-sensitive calcium channels.

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Production of manganese peroxidase from Pleurotus ostreatus using a rotary draft tube bioreactor (RTB) and characterization of its activity (회전식 통풍관 생물반응기 사용에 따른 느타리균의 manganese peroxidase 생산 및 특성)

  • Ha, Hyo-Cheol
    • Journal of Mushroom
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    • v.19 no.4
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    • pp.316-321
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    • 2021
  • Ligninolytic enzymes were produced by Pleurotus ostreatus No.42, cultivated in a new kind of bioreactor that has a rotating draft tube with a helical ribbon. Maximum laccase (Lac) production (about 8,200 U/bioreactor) was reached after 3 days of incubation, then production decreased. Production of manganese peroxidase (MnP) in this fermenter reached a maximum level of about 8,400 U/bioreactor after 6 days of incubation. Lignin peroxidase (LiP) was not detected under these growth conditions. These results indicate that the rotary draft tube bioreactor (RTB) is compatible with large scale production of ligninolytic enzymes. MnP produced under these fermentation conditions was purified via a multistep process that included chromatography on Sepharose CL-6B, prep grade Superdex 75, and Mono-Q. This major isoenzyme was confirmed to have an apparent molecular weight of 36,400 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), and its isoelectric point (IEF) was determined to be 3.95. N-terminal sequencing of the major isoenzyme from this fermentation was identical to that reported for an MnP3 isoenzyme isolated under different cultivation conditions, including stationary and shaking culture.

Studies on Mild Mutants of Tabacco Mosaic Virus I. Induction of Mild Mutants and Their Characteristics (약독 담배 모자이크 바이러스 I. 약독바이러스의 유기 및 특성)

  • Choi Jang Kyung;Son Kyung Ok
    • Korean Journal Plant Pathology
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    • v.1 no.1
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    • pp.3-11
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    • 1985
  • Three mild mutant strains of tobacco mosaic virus (TMV) were isolated from Nicotiana tabacum var. Samsun incubated at $38^{\circ}C$ for 10 days after inoculation with a wild type of TMV-OM strain. They were designated into Tg 5272, Tw 227 and Tw 333. All mild strains could be distinguished from TMV-OM by their reactions on different indicator plants. The mild strains induced the mild mottling without distinct symptoms, whereas the wild strain produced severe mosaic, rugose and stunting on tobacco and red pepper plants. Tw 227 and Tw 333 produced smaller necrotic spots than those of Tg 5272 and TMV-OM on N. glutinosa and Datura stramonium. The former two strains also produced ring spots and mosaic on Gomphrena globosa compared with necrotic spots by the latter strains. Three mild strains were serologically identical to TMV-OM. Their physical properties were thermal inactivation point $80-85^{\circ}C$, dilution end point between $10^{-4}\;and\;10^{-6}$, and longevity in vitro 7days or longer. Ultraviolet absorption spectra of purified preparations of the mild strains and TMV-OM were identical, with a minimum at 247nm, a maximum at 260nm, and a slight shoulder at 290nm. Electrophoresis of the strains in polyacrylamide-agarose gel showed that all the strains formed one major band and two minor bands, except for one minor band of Tw 333. However, when sodium dodecyl sulfate was added to the purified viruses before electrophoresis, each strain formed only one major band.

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Effects of Cyclobuxine E on Two Distinct Types of Potassium-Activated Calcium Channels in an Intestinal Smooth Muscle (흰쥐 장관에 있어 칼륨에 의해 활성화되는 칼슘 채널에 대한 Cyclobuxine E의 영향)

  • Lee, Jong-Hwoa;Kwon, Jun-Tack;Cho, Byung-Heon;Choi, Kyu-Hong;Kim, Yu-Jae;Kim, Jong-Bae;Kim, Chun-Sook;Cha, Young-Deog;Kim, Young-Suk
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.53-58
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    • 1989
  • For several years, we investigated the pharmacological action of several substances isolated from Buxus microphylla var koreana Nakai, which had been used as folk remedies of malaria and venereal disease. Cyclobuxine $D(C_{25}H_{42}ON_2)$, a steroidal alkaloid, exerted an antiinflammatory action, hypotensive and bradycardic effects in rats. In the present study, we isolated alkaloid from the acetone-insoluble fraction of the strong bases of this plants. This alkaloid $(C_{25}H_{38}ON_2)$ was identified as a steroidal alkaloid contained a cyclopropane ring by physical and chemical methods. It is a derivative of cyclobuxine D and named cyclobuxine E. We examined the effect of cyclobuxine E on the contractile response induced by acetylcholine and two distinct types of potassium-activated calcium channels in an intestinal smooth muscle of the rat. Cyclobuxine E inhibited significantly the Ach-induced contraction. The isolated longitudinal muscle from the rat duodenum was immersed calcium-depleted potassium depolarizing solution. Ten minutes after, 1.8 mM $CaCl_2$ was added to muscle bath and elicited a biphasic increase in muscle tension. Cyclobuxine E produced an appreciable inhibition of both components of the mechanical response. In addition, Cyclobuxine E introduced at a point when the tonic response had reached its maximum level, caused the muscle to exhibit a rapid loss of tension. Based on these experimental results, we proposed the possibility that the inhibitory action of cyclobuxine E on the isolated rat duodenum may be due to inhibiting the transmembrane fluxes of calcium ion in potassium-activated calcium channels.

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Efficient Uncertainty Analysis of TOPMODEL Using Particle Swarm Optimization (입자군집최적화 알고리듬을 이용한 효율적인 TOPMODEL의 불확실도 분석)

  • Cho, Huidae;Kim, Dongkyun;Lee, Kanghee
    • Journal of Korea Water Resources Association
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    • v.47 no.3
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    • pp.285-295
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    • 2014
  • We applied the ISPSO-GLUE method, which integrates the Isolated-Speciation-based Particle Swarm Optimization (ISPSO) with the Generalized Likelihood Uncertainty Estimation (GLUE) method, to the uncertainty analysis of the Topography Model (TOPMODEL) and compared its performance with that of the GLUE method. When we performed the same number of model runs for the both methods, we were able to identify the point where the performance of ISPSO-GLUE exceeded that of GLUE, after which ISPSOGLUE kept improving its performance steadily while GLUE did not. When we compared the 95% uncertainty bounds of the two methods, their general shapes and trends were very similar, but those of ISPSO-GLUE enclosed about 5.4 times more observed values than those of GLUE did. What it means is that ISPSOGLUE requires much less number of parameter samples to generate better performing uncertainty bounds. When compared to ISPSO-GLUE, GLUE overestimated uncertainty in the recession limb following the maximum peak streamflow. For this recession period, GLUE requires to find more behavioral models to reduce the uncertainty. ISPSO-GLUE can be a promising alternative to GLUE because the uncertainty bounds of the method were quantitatively superior to those of GLUE and, especially, computationally expensive hydrologic models are expected to greatly take advantage of the feature.

Fermentation Patterns of Green Onion Kimchi and Chinese Cabbage Kimchi (파김치와 배추김치의 발효양상)

  • Lee, Hun-Joo;Joo, Yun-Jung;Park, Chan-Sun;Lee, Jung-Sook;Park, Yong-Ha;Ahn, Jong-Seog;Mheen, Tae-Ick
    • Korean Journal of Food Science and Technology
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    • v.31 no.2
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    • pp.488-494
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    • 1999
  • Changes of lactic acid bacteria and fermentation patterns were investigated during fermentation of Green Onion Kimchi and Chinese Cabbage Kimchi at 10 and $20^{\circ}C$. Fermentation of Green Onion Kimchi proceeded more slowly than Chinese Cabbage Kimchi in point of changes of pH, total acidity and total viable cell number. Maximum number of total viable cell, Leuconostoc, and Lactobacillus in Green Onion Kimchi were smaller than in Chinese Cabbage Kimchi. And these differences were larger in fermentation at $10^{\circ}C$. Total sugar content of Green Onion Kimchi was higher than Chinese Cabbage Kimchi not only at the beginning of fermentation but also at the end of fermentation. Therefore, the reason for the slow fermentation of Green Onion Kimchi was not low sugar content. Major lactic acid bacteria of properly fermented Green Onion Kimchi were identified as Lactobacillus plantarum and Leuconostoc mesenteroides which had been reported to be major lactic acid bacteria isolated from Chinese Cabbage Kimchi.

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Monitoring Bacillus cereus and Aerobic Bacteria in Raw Infant Formula and Microbial Quality Control during Manufacturing (영.유아용 식품원료의 Bacillus cereus와 일반세균 모니터링 및 제조공정 중 미생물 품질제어)

  • Jung, Woo-Young;Eom, Joon-Ho;Kim, Byeong-Jo;Ju, In-Sun;Kim, Chang-Soo;Kim, Mi-Ra;Byun, Jung-A;Park, You-Gyoung;Son, Sang-Hyuck;Lee, Eun-Mi;Jung, Rae-Seok;Na, Mi-Ae;Yuk, Dong-Yeon;Gang, Ji-Yeon;Heo, Ok-Sun;Yoon, Min-Ho
    • Korean Journal of Food Science and Technology
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    • v.42 no.4
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    • pp.494-501
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    • 2010
  • The purpose of this study was to examine the presence of Bacillus cereus, aerobic bacteria and coliforms in the raw material of infant formulas and investigate the manufacturing process in terms of microbial safety. Among ten kinds of raw infant formula material samples (n=20), Bacillus cereus appeared in two (n=4). Aerobic bacteria were not detected in raw infant formula material or maximum 4.15 log CFU/g. Eleven species of aerobic bacteria were isolated and 76% of them were Sphingomonas paucimobilis, Pseudomonas fluorescens, Rhizobium radiobactor, or Stenotrophomonas maltophilia. A Pearson's correlation analysis revealed that the most influential factors for detecting Bacillus cereus were aerobic bacteria and coliforms. In other words, when the measured values of aerobic bacteria and coliforms were higher, the possibility that Bacillus cereus would appear increased. In a regression model to predict Bacillus cereus, the rate of appearance was correlated with aerobic bacteria and coliforms, and its contribution rate for effectiveness was 86%. Improving microbial quality control by pasteurization, spray dry, popping and extrusion resulted in a decrease in the numbers of Bacillus cereus, aerobic bacteria and coliforms in the raw materials. The results suggest that a hazard analysis and critical control point system might be effective for reducing microbiological contamination.