• The Korean Journal of Mycology
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• v.24 no.2 s.77
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• pp.93-103
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• 1996

In order to find out effect on the inorganic and organic compounds as a soil amendment to control Fusarium wilt of cucumber caused by Fusarium oxysporum f. sp. cucumerinum, this study was conducted during the last two years from 1993 to 1995. According to add 14 inorganic chemicals (1%, w/v) including $Al_2(SO_4)_3$ individually in vitro, these chemicals were confirmed their suppression, and especially Alum, CaO and $Al_2(SO_4)_3$ suppressed not only $20.9{\sim}25.0$ percent on mycelial growth of the fungus, but also inhibited $72.8{\sim}97%$ on conidial germination. $Ca(NO_3)_2$ suppressed mycelial growth only, while KCl, $K_2SO_4,\;NH_4NO_3$, and Urea suppressed conidial germination. The 7 chemicals were finally seleced. Composted pine bark (CPB) suppressed definely more than 90% on conidial germination in the different extract concentration (2,5 and 10%), although mycelial growth on extract medium of CPB and milled alfalfa leaves (MAL) were not remarkable. The antagonist Trichoderma sp. (Tr-3) mixed with an amended soil (1%, w/w) containing composted pine bark showed a good mycelial growth to compete the causal fungus. And the antagonist Pseudomonas sp. (7-1-3) was also confirmed its antagonistic ability with culture filterate. It is known that a CPB soil amendment mixed with the two antagonists (1%, w/w) controlled almost completely Fusarium wilt of cucumber in greenhouse pots and a field experiment. It is therefore expected that biocontrol on Fusarium wilt of cucumber by a soil amendment can be applied to farmmer's fields.

• Journal of agriculture & life science
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• v.46 no.2
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• pp.27-33
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• 2012

In this study, we evaluated environmental-friendly disease control methods using essential oils, antagonistic bacteria, or cooking oil and egg yolk mixture (COY). Among the five tested plant essential oils, Eucalyptus approximans oil shown the highest effect to control of the downy mildew disease (60% disease control value). Interestingly enough, well known antagonistic bacteria against various fungal pathogens were appeared lower control efficiency than plant essential oils. In field conditions, the cooking oil and yolk mixture (COY) treatments shown significantly decreased the downy mildew incidence with 0.3% (disease conttrol value 84%) and 0.5% concentration (disease control value 91%). Our findings suggest that the COY has a great potential as the eco-friendly downy mildew disease control formulation.

• The Korean Journal of Pharmacology
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• v.26 no.2
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• pp.153-160
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• 1990

5-Hydroxytryptamine (5-HT) was reported to elicit natriuresis and diuresis when given intracerebroventricularly (icv) and these effects were shown to be abolished by icv methysergide, $5-HT{_1}$ antagonist, thus suggesting that central tryptaminergic system may also participate in the regulation of renal function. We tried in this study to elucidate the role of $5-HT_2$ receptors in the central tryptaminergic regulation of renal function, observing the effects of icv ketanserin, a specific $5-HT_2$ antagonist. Ketanserin (KET) icv in doses of $120{\mu}g$ $(=0.3\;{\mu}moles)/kg$ produced significant natriuresis without affecting renal hemodynamics, indicating that it resulted from decreased tubular Na reabsorption. Systemic blood pressure decreased slightly but significantly. When given iv, no significant effect was observed. 5-HT, $200{\mu}g/kg$ icv, produced mild but significant natriuresis and diuresis. However, after KET, $40{\mu}\;g/kg$ icv, a dose which minimally affects renal function, the natriuresis and diuresis by 5-HT was greatly augmented, with the fractional excretion of filtered sodium reaching 9.3%. The renal effects of other biogenic amines administered icv, such as norepinephrine, dopamine and histamine, were not significantly affected by the KET pretreatment. These observations suggest that central tryptaminergic system influences renal function in dual ways, i.e., natriuretic and diuretic influence via $5-HT_1$ receptors, whereas $5-HT_2$ subtypes mediate the antinatriuretic and antidiuretic effects, and that the central tryptaminergic system plays a role in the regulation of rabbit renal function.

• THE HEALTH and ORGANIC FARMING
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• no.223
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• pp.1-12
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• 2006

친환경유기농업 연수회 유치 요청쇄도/우리나라 고유의 기농산품을 개발하여 세계화에 진력하자/본회 제천 유기농업연수원 집체교육/우리의 산야초/토양검정은 친환경적 토양관리의 첫단계/휴면지회 해산 공고/제2차 친환경농업 육성목표와 방향/유기농업 자연과 인류 공존의길/유기농 농사 20년 넘게 지은 한국유기농업협회 안종근 이사가 말하는 진짜 유기농 식품/"친환경 농업.생태관광 추진을"/두자기 비료로 유기농작물의 고품질 다수확 생산을 체계적으로 보다 쉽게 하는 방법/광역친환경농업단지 선정/식물을 깨워 저항성을 갖게 하자/오이의 생리장해/엽채류 균핵병 방제/호주 친환경인증기관'국내인증기관' 지정시도/"제주도친환경우리농산물학교 급식사용에관한지원조례"소개/2.3월중 협회 일정 안내/해충의 습성을 이용한 퇴치/1월중 새식구 명단/제천.동부지회 창립총회/"친환경 농산물 믿어도 된다"/'새로운 도전과 희망' 벤처농업박람회 4월에/유기 및 일반 농산물의 품질 비교에 관한 연구/길항미생물

• Journal of the korean academy of Pediatric Dentistry
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• v.28 no.3
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• pp.441-446
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• 2001

Flumazenil is a competitive antagonist of benzodiazepines. It is usually administered intravenously. However, if the intravenous route is not available then other routes of drug administration should be considered. This study was designed to evaluate the reversal effects of flumazenil after nasal administration. Twenty-five young, healthy adult volunteers participated in this clinical trial. The dosage of 0.08mg/kg midazolam was administered intravenously to induce deep sedation. Ten minutes after midazolam administration, 0.5mg of flumazenil was dropped nasally, over a period of one minute. Blood samples were taken to measure the concentration of midazolam and flumazenil at 0, 5, 10, and 20min after nasal administration of flumazenil, using High Performance Liquid Chromatography. The degree of sedation was evaluated with sedation score and bispectral index (BIS), Statistical analysis was performed by multivariate ANOVA and correlation analysis (P<0.05). Peak serum flumazenil concentration was reached in 10min. Sedation score decreased after midazolam administration and showed a significant increase after flumazenil administration. However, BIS decreased during the first 10min after midazolam administration and then no significant changes after flumazenil administration. There were two instances representing rapid and complete reversal of midazolam after intranasal administration of flumazenil. In conclusion, intranasal flumazenil administration may be effective in some patients when intravenous route is not available in condition of benzodiazepine overdose.

• Korean Journal of Weed Science
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• v.10 no.4
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• pp.328-337
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• 1990

The incividual and combined effects of the chloroacetanilide herbicide pretilachlor and of the safener fenclorim on the growth and selected physiological processes of rice (Oryza sativa L., var 'Lemont')were evaluated under greenhouse and laboratory conditions. Fenclorim applied at rates ranging from 50 to 300 g a.i./ha antagonized the injurious effects caused by 150 to 900 g a.i./ha of pretilachlor on 15-day old wet-sown rice grown under greenhouse conditions. When used rates of 150 g/ha or higher, fenclorim reversed completely the effects of all doses of pretilachlor on rice. When the two compounds were given simultaneously, fenclorim enhanced the uptake of $^{14}C$pretilachlor into rice leaf mesophyll protoplasts measured for 1 hr, indicating that competition for uptake at the protoplast level is not involved in the protective action of this safener. The safener-induced stimulation of pretilachlor uptake was particularly evident when fenclorim was used at concentrations of 10, 20 and $40{\mu}M$. Following 4 hr of incubation, individual treatments with pretilachlor inhibited the in vitro incorporation of radiolabeled precursors into proteins, DNA, and lipids of rice leaf protoplasts only when used at the high concentration of $100{\mu}M$M. Individual treatments with high concentrations (10 or $100{\mu}M$) of the safener fenclorim inhibited the incorporation of radiolabeled precursors into proteins and lipids of rice protoplasts, but had no DNA synthesis. The combined effects of pretilachlor and fenclorim on the incorporation of radiolabeled precursors into these macromolecules of isolated rice mesophyll protoplasts appeared to be additive or slightly synergistic rather than antagonistic. Fenclorim at $1{\mu}M$ antagonized the effects of pretilachlor on total lipids of rice leaf protoplasts. In addition, individual and combined treat-menu with pretilachlor and fenclorim influenced the incoroporation of$^{14}C$acetate into polar lipids, triglycerides and steryl esters of rice leaf protoplas causing a redistribution of carbon in these lipid fractions. However, these effects were not large enough to explain the herbicidal activity of pretilachlor or to account for the protective action of the safener fenclorim. Overall, the uesults of the present study idnicate that the safener fenclorim does not seem to protect rice against pretilachlor injury by antagonizing its effects on protein, DNA, or lipid syntheses.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.13-21
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• 1996

Intracellular calcium concentration ($[Ca^{2+}]_i$) may play a crucial role in a variety of neuronal functions. Here we report that in primary culture of mouse cerebellar granule cells nicotinic acetylcholine receptors (nAChRs) are expressed in a specific developmental stage and involved in the regulation of intracellular calcium homeostasis. Nicotine-mediated calcium responses were measured using $^{45}Ca^{2+}$ or fluorometrically using the calcium-sensitive fluorescent dye fura-2. Maximal uptake of $^{45}Ca^{2+}$ evoked by nicotine in mouse cerebellar granule cells were revealed $8{\sim}12$ days in culture. In contrast, nicotine did not alter the basal $^{45}Ca^{2+}$ uptake in cultured glial cells. In cerebellar granule cells nicotine-evoked $^{45}Ca^{2+}$ uptake was largely blocked by the NMDA receptor antagonists. Glutamate pyruvate transaminase (GPT). which removes endogenous glutamate, also prevented nicotine effects, implying the indirect involvement of glutamate in nicotine-mediated calcium responses. Fluorometric studies using fura-2 showed two phases of nicotine-evoked $[Ca^{2+}]_i$ rises: the initial rising phase and the later plateau phase. Interestingly, the NMDA receptor antagonists and GPT appeared to inhibit only the later plateau phase of nicotine-evoked $[Ca^{2+}]_i$ rises. The present results imply that nicotine mediated $^{45}Ca^{2+}$ uptake and $[Ca^{2+}]_i$ rises are attributed to the calcium fluxes through both nAchRs and NMDA receptors in a time-dependent manner. Consequently, nAChRs may play an important role in neuronal development by being expressed in a specific developmental stage and regulating the intracellular calcium homeostasis.

• Journal of Life Science
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• v.33 no.2
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• pp.129-137
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• 2023

Reactive oxygen species (ROS) play an essential role in a variety of cellular physiological phenomena. The present study assessed the signaling axis that mediates the lysophosphatidic acid (LPA)-induced migration of SKOV-3 cells. Insulin-like growth factor-1 (IGF-1) stimulated SKOV-3 cell migration in a time- and dose-dependent manner. Similarly, LPA stimulated SKOV-3 cell migration and the phosphorylation of Akt in a time- and dose-dependent manner. The pharmacological inhibition of LPA receptors (LPA₁/LPA₃) significantly suppressed LPA-induced SKOV-3 cell migration. However, IGF-1-induced SKOV-3 cell migration was not affected by the inhibition of LPA1 and LPA3. Pharmacological inhibition of phosphoinositide 3-kinase (PI3K) or Rho-associated kinase (ROCK) significantly suppressed LPA-induced migration, whereas the inhibition of MAPK kinase (MEK) had no effect. Inhibition of PI3K or ROCK completely suppressed LPA-induced ROS generation, and suppression of nicotinamide adenine dinucleotide phosphate oxidase (NOX) or chelation of ROS by N-acetylcysteine (NAC) blocked LPA-induced SKOV-3 cell migration. LPA-induced ROS generation was suppressed by silencing Rictor or Akt1 but not Raptor or Akt2. Silencing Rictor or Akt1 significantly suppressed LPA-induced SKOV-3 cell migration, whereas silencing Raptor or Akt2 had no effect. Finally, the overexpression of the constitutively active form Akt1 (CA-Akt1) significantly enhanced the LPA-induced migration of SKOV-3 cells. Given these results, we suggest that LPA stimulates SKOV-3 cell migration by ROS generation, which is mediated by the mTORC2/Akt1/NOX signaling axis.

• Journal of fish pathology
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• v.14 no.1
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• pp.46-53
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• 2001

The present study was undertaken to investigate and compare the effect and mode of action of tachykinins on isolated strip preparations of the intestinal smooth muscle from the nile tilapia, Oreochromis niloticus and the Israel carp, Cyprinus carpio. Both of neurokinin 1(NK-1) receptor agonist, substance P(SP) and neurokinin 2(NK-2) receptor agonist, neurokinin A(NKA) caused concentration-dependent contractions of intestinal smooth muscle in the nile tilapia and the israel carp. The efficiency and potency of these agonists varied between two fish species. In the nile tilapia intestine, the efficiency and potency of SP were greater than those of NKA. However, the efficiency and potency of SP were similar to those of NKA. In the nile tilapia intestine and the israel carp intestine, the contractile responses of SP and NKA were noncompetitively antagonized by NK-1 receptor antagonist, L-732, 138 but unaffected by NK-2 receptor antagonist, MDL 29913. In addition, SP-induced contractions in the both of preparation were significantly inhibited by muscarinic antagonist, atropine($5{\times}10^{-7}$M) and ganglionic inhibitor, tetrodotoxin($2{\times}10^{-7}$M) but NKA-induced contractions were unaffected by those. These results indicate that two tachykinin agonists, SP and NKA predominately modulate the mechanical activity of isolated preparation from the nile tilapia and the israle carp directly through the activation of NK-1 receptor on the intestinal smooth muscle cells, but in the case of SP action, the indirect action through activation of cholinergic nerve terminals seems to be also implicated.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.s02
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• pp.115-120
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• 1989

Universal characteristics of ginseng replanting problems appeared to be decrease in root yields due to root rot and inhibition of root growth. Incitants of ginseng replanting problems have not been clearly elucidated, however, it appeared to be a complex phenomenon with several pathogenic soil microorganisms and environmental changes in the soil due to decomposition of ginseng debris such as rootlets and shoots. Decomposition of ginseng debris may cause direct or indirect damage to the root. The effect of conventional fungicide on the control of the problems has not been recognized. However, it has been suggested that treatment with soil fumigants may solve the problems. Meanwhile paddy-rice and ginseng rotation system appeared to be the best way of solving the problems so far.