• Title/Summary/Keyword: Inhibition rate

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Inhibition of Recovery from Potentially Lethal Damage by Chemicals in Chinese Hamster Cells is Realized through the Production of Irreversible Damage

  • Kim Jin Kyu;Komarova Ludmila N.;Tkhabisimova Marianna D.;Petin Vladislav G.
    • Korean Journal of Environmental Biology
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    • v.23 no.4
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    • pp.390-397
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    • 2005
  • The inhibition of cell recovery might be proceeded via either the damage of the mechanism of the recovery itself or via the formation of irreversible damage which could not be repaired at all. Both these processes may take place at the same time. Any of these possibilities would result in a decrease in both the rate and extent of cell recovery. To distinguish them, a quantitative approach describing the process of recovery as a decrease in the effective radiation dose was applied to experimental data on the recovery from potentially lethal damage in Chinese hamster cells exposed to X-rays alone or combined with various chemicals (pyruvate, novobiocin, lactate, nalidixic acid, 3-aminobenzamide). For these particular cases, it is concluded that the recovery process itself is not damaged and the inhibition of the recovery is entirely due to the enhanced yield of the irreversibly damaged cells.

Chlorine Inhibition on the Denitrifying Activity of Activated Sludge Microorganisms (활성슬러지 미생물의 탈질 활성에 대한 염소의 저해)

  • Choi, Jin-Taek;Nam, Se-Yong
    • Journal of Environmental Health Sciences
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    • v.33 no.4
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    • pp.338-343
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    • 2007
  • Chlorine inhibition on the denitrifing activity of activated sludge treating dairy wastewater was investigated in this study. Filamentous bulking was caused artificially by a sudden load of feed and monitored by measuring sludge volume index. In cases of the activated sludge and bulking sludge which were contacted with chlorine as $7.5\;mgCl_2/gVSS/day$ for bulking control, the decreases of specific denitrification of $32.2{\sim}40.4%\;and\;43.5{\sim}46.5%$ were shown in comparison to the control group which was not reacted with chlorine, respectively. In continuous operation, it was observed that the removal efficiency of total nitrogen was more susceptible to chlorine than the removal efficiency of total phosphorus.

Inhibitory potency of Acetylcholinesterase and Amyloid beta(1-42) peptide aggregation to the Extracts of Enthusiasm Reducing herbals (청열약 추출물들의 아세틸콜린에스테라제 저해와 베타아밀로이드 펩티드 응집 억제 효능)

  • Kwon, Young-Ee
    • Korean Journal of Pharmacognosy
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    • v.38 no.4
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    • pp.308-311
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    • 2007
  • Inhibition of acetylcholinesterase and amyloid beta(1-42) peptide is good drug targets for Alzheimer's disease therapeutics. Among the twenty enthusiasm reducing herbals, the 70% methanol extracts (1 mg/ml) of Moutan Radicis Cortex and Forsythiae Fructus showed 91.5% and 85.3% about acethylcholinesterase inhibition, respectively. The extracts (1 mg/ml) of Coptidis Rhizoma and Paeoniae Radix Rubra showed more than 85% inhibition rate against amyloid beta (1-42) peptide aggregation. The neuroprotective effect of the extracts (1 mg/ml) of Moutan Radicis Cortex, Forsythiae Fructus and Paeoniae Radix Rubra showed 90.0%, 87.4% and 85.1% to compare with amyloid beta (1-42) peptide treated cells (IMR-32), respectively. Three herbs, Moutan Radicis Cortex, Forsythiae Fructus and Paeoniae Radix Rubra are promising candidates from natural products for development of Alzheimer's disease therapeutics.

Inhibition of Compylobacter jejuni in Chicken by Ethanol, Hydrogen Peroxide, and Organic Acids

  • Shin, Soon-Young;Hwang, Han-Joon;Kim, Wang-June
    • Journal of Microbiology and Biotechnology
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    • v.11 no.3
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    • pp.418-422
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    • 2001
  • Growth inhibition of Compylobacter jejuni ATCC 33291 was observed in the presence of various preservatives at various temperatures. The addition of ethanol (0.5% to 5%), hydrogen peroxide (0.05%), acetic acid (1%), propionic acid, benzoic acid, and sorbic acid showed strong antibacterial activities against C. jejuni at pH 5.5 or 6.5. The addition of 1% acetic acid and lactic acid were most effective at $42{\circ}C, followed by $25{\circ}C$ and $4{\circ}C$. This indicated that the inhibitory effect was temperature dependent. In the chicken model system, the practical death rate of C. jejuni in the FBP-media with 1% acetic temperatures ($4{\circ}$C$, $25{\circ}$C, and $42{\circ}$). Therefore, precaution has to be taken in the use of organic acids as a disinfectant in the chicken slaughterhouse.

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Effect of Dynamic Flow on the Structure of Inhibition Layer in Hot-dip Galvanizing

  • Jin, Young Sool;Kim, Myung Soo;Kim, Su Young;Paik, Doo Jin
    • Corrosion Science and Technology
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    • v.10 no.1
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    • pp.30-36
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    • 2011
  • The effect of dynamic flow or forced convection were investigated and compared on the formation of inhibition layer, galvanizing and galvannealing reactions through the hot-dip galvanizing simulator with the oscillation of specimen in zinc bath, continuous galvanizing pilot plant with zinc pumping system through the snout and continuous galvanizing operation with Dynamic $Galvanizing^{TR}$ system. The interfacial Al pick-up was not consistent between the results of simulator, pilot plant and line operation, but the morphology of inhibition layer became compact and refined by the forced convection. The growth of Fe-Zn intermetallics at the interface was inhibited by the forced convection, whereas the galvannealing rate would be a little promoted.

Selection of Microorganisms for Probiotics and Their Characterization (생균제로서 가능성이 있는 미생물의 선별 및 특성)

  • 박홍석;이선희;엄태붕
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.27 no.3
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    • pp.433-440
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    • 1998
  • In order to select probiotics with a high survival rate in gut and the growth inhibition of virulent pathogens to human beings or animals, we have examined a variety of microorganisms to assess the acid, bile, and pancreatic tolerance and the growth inhibition of E. colt O8 and Salmonella choleraesuis ATCC 8391. Lactobacillus acidophilus KCTC 3155 was shown to inhibit the growth of E. coli and Salmonella dramatically within 24 h of incubation, although it was vulnerable to the exposure of bile acids. Bacillus polyfermenticus showed a good growth inhibition against E. coli, with a moderate acid and bile tolerance, while Clostridium butyricum KCTC 1786 inhibited the growth of E. coli and Salmonella slightly with a good bile tolerance. However, Saccharomyces cerevisiae KCTC 7928 and Aspergillus oryzae KCTC 6075 did not inhibit the growth of E. coli and Salmonella, suggesting that these microorganisms can be used as the sources of nutritional suppliment rather than as probiotics itself.

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Inhibition of Dopamine Biosynthesis by Coralyne in PC12 Cells (Coralyne에 의한 PC12 세포중의 도파민 생합성 저해작용)

  • Shin, Jeong-Soo;Lee, Myung-Koo
    • Korean Journal of Pharmacognosy
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    • v.30 no.1
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    • pp.79-83
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    • 1999
  • The effects of coralyne, a protoberberine isoquinoline compound, on dopamine biosynthesis in PC12 cells were investigated. Coralyne decreased the dopamine content dose-dependently $(46.3%\;inhibition\;at\;20\;{\mu}M\;for\;24 hr).$ Dopamine content was lowered at 6 hr and reached minimal level at 24 hr after exposure to coralyne at $20\;{\mu}M.$ The decreased dopamine level was maintained up to 48 hr and recovered to the control level at about 72 hr. Tyrosine hydroxylase, the rate-limiting enzyme in the catecholamine biosynthesis, was also inhibited at $20\;{\mu}M\;of\;coralyne$ by 16.1% relative to control. These results suggest that the inhibition of tyrosine hydroxylase by coralyne with a single treatment might be partially contributed to the decrease in dopamine content in PC12 cells.

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Immunohistochemical Changes of Apoptotic Control Genes by Chronic Inhibition of Nitric Oxide in Rats

  • Bae, Hyung-Joon
    • Biomedical Science Letters
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    • v.18 no.4
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    • pp.420-427
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    • 2012
  • Sprague-Dawley (SD) rats were orally administered with NG-nitro-L-arginine methyl ester (L-NAME), which inhibits or blocks the production of nitric oxide from L-arginine in vascular endothelial cells and vessel tissue. We examined the effects of nitric oxide on some physiological changes such as blood pressure and heart rate, and confirms the apoptosis induced by the suppressed nitric oxide activity in the kidney. This study was performed to investigate correlation between the activities of nitric oxide and apoptosis by immunohistochemical changes of apoptotic control proteins with regulated chronic inhibition of nitric oxide. In the kidney from L-NAME-treated group, immunohistochemical reaction to the antigens of apoptosis inhibiting proteins such as bcl-2 and bcl-xL, exhibited a time-dependent reduction. The expression of apoptosis-inhibiting proteins such as bax and p53 increased expression in proportion to the duration of treatment. The most sensitive apoptosis regulating proteins to L-NAME were p53 in stimulation and bcl-2 in inhibition, respectively.

Isolation of Constituents with Nitric Oxide Synthase Inhibition Activity from Phryma leptostachya var. asiatica

  • Kim, Donghwa;Lee, Sang Kook;Park, Kyoung-Sik;Kwon, Na-Yun;Park, Hee-Juhn
    • Natural Product Sciences
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    • v.25 no.1
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    • pp.34-37
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    • 2019
  • Phytochemical studies were performed to identify the active principles of Phryma leptostachya var. asiatica (Phyrymaceae) for anti-inflammation. The anti-inflammatory activity was assessed by measuring the inhibition rate on nitric oxide (NO) formation in lipopolysaccharide (LPS)-activated macrophage 264.7 cells. Of the five compounds including ursolic acid, phrymarolin I, harpagide, haedoxancoside A, and acteoside isolated from this plant, ursolic acid showed the most prominent inhibition of NO formation. Therefore, ursolic acid may be the anti-inflammatory principle of Phryma leptostachya var. asiatica.

The Studies of the Heechum-san(HCS)'s Effects on the Thrombosis (희첨산이 혈전에 미치는 영향)

  • 김민상;김윤식;설인찬
    • The Journal of Korean Medicine
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    • v.25 no.1
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    • pp.21-30
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    • 2004
  • Objectives : We aimed to identify the effects of Heechum-san(HCS) On the thrombosis. Methods : We measured the protective effects of HCS on pulmonary thromboembolism induced by collagen and epinephrine, intravascular coagulation induced by dextran. Results : HCS showed a effective inhibition on coagulation of platelets induced by ADP or epinephrine. HCS showed survival rate of 14.28% on pulmonary thrombo- embolism caused by collagen and epinephrine. On the measure of the blood flow rate induced by the thrombus, in vivo HCS accelerated the blood flow rate. Conclusions : HCS has antithrombotic effects.

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