• Research in Plant Disease
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• v.9 no.3
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• pp.174-178
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• 2003

Pseudomonas sp. antagonistic to Colletotrichum truncatum and C. gloesporioies was selected as a biological control agent for soybean anthracnose. Pseudomonas sp. inhibited the mycelial growth of pathogens effectively as the funhicides such as benomyl and fluazinam in vitro tests without any adverse effects on soybean. Seed treatment with Pseudomonas sp. increased emergence rate of soybean seeds significantly after inoculaton with C. truncatum. When the suspension of Pseudomonas sp. was sprayed on soybean plants, the control efficacy was not different from that of fungicides, benomyl and fluazinam two weeks after treatment, however the efficacy did not last long enough after three weeks.

• Journal of Pharmaceutical Investigation
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• v.25 no.2
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• pp.117-123
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• 1995

For the effective administration of narcotic antagonist, the application of sustained release implantable systems with biodegradable polyphosphazene was examined. Using poly[(diethyl glutamate)-co-(ethyl glycinate) phosphazene], the implantable devices containing naloxone hydrochloride were prepared and in vivo implantation studies were carried out subcutaneously in rat and rabbit with this preparation for the biocompatibility and pharmacokinetics. The histological finding in rats at initial time period was the inflammation that occurred focally around the implants, but they were showed subsequent mild and limited chronic inflammations and the irreversible changes such as necrosis and degeneration of the muscle or connective tissues were not observed. Therefore the placebo and naloxone implants are considered to be biocompatible formulations histologically. In pharmacokinetic studies, the release of naloxone from the naloxone implants into blood plasma was maintained in 192 hours, but the initial burst effect was observed. If this problem was solved, the application for the narcotic antagonist sustained release systems can be expected.

• Applied Biological Chemistry
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• v.48 no.1
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• pp.48-52
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• 2005

Six stains of plant growth promoting rhizobacteria were selected through germinating seed assay and root colonization assay. Among them, SKU-78 strain induced significant suppression of bacterial wilt disease in tomato and pepper plants. Seed treatment followed by soil drench application with this strain resulted in over 60% reduction of bacterial wilt disease compared with the control. It was suggested that SKU-78 strain activated the host defense systems in plants, based on lack of direct antibiosis against pathogen. According to Bergey's Manual of Systemic Bacteriology and 16S rDNA sequence data, SKU-78 stain was identified as Bacillus sp. SKU-78.

• Microbiology and Biotechnology Letters
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• v.10 no.3
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• pp.171-175
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• 1982

An oxytetracycline as being a tetracycline-antibiotic substance displayed a general synergism in the antimicrobial activity by the interaction of ginseng saponin and antibiotics, but did not to Sarcina maginata. Penicillin G.Na as being a $\beta$-lactam-antibiotic substance displayed a synergism in the antimicrobial activities by the addition of ginseng saponin to microorganisms used, but changed the effects in the antimicrobial activity of penicillin G.Na against the genus Serratia. An antimicrobial activity by the addition of ginseng saponin to antibiotics showed a non-specificity, and it varied synergism or antagonism to Gram-positive or Gram-negative bacterium. It was assumed that a drug-resistance could be eliminated by the dual administration of ginseng saponin and antibiotics.

• Research in Plant Disease
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• v.8 no.4
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• pp.234-238
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• 2002

In vitro and in vivo activities of a biocontrol agent, Bacillus stearothermophilus strain YC4194 was evaluated for the control of Pythium damping-off of cucumber. B. stearothermophilus YC4194 inhibited germination of cystospores and formation of zoosporangia of Pythium aphanidermatum in vitro. Incorporation of a bentonite and talc based formulation(10$^{9}$ cfu/g) of B. stearothermophilus YC4194 to the nursery soils (10 g/ι soil) resulted In a significant (p=0.01) reduction in the disease severity of cucumber damping-off after inoculation with P. aphanidermatum. The control efficacy of B. stearothermophilus YC4194 formulation was not different from that of the fungicides, dimethomorph, metalaxyl, ethaboxam. When the cucumber plants were transplanted to the soil inoculated with P. aphanidermatum zoospores, the B. stearothermophilus YC4194 maintained the high population density in rhizosphere soil upto 10$^{7}$ cfu/g until 15 days after treatment.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.412-415
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• 2003

In order to elucidate the mechanism between cytotoxicity of methhylmercuric chloride(MMC) and oxygen radicals in cultured osteoblasts of neonatal mouse, cell viability was measured by MTT assay in osteoblasts treated with 1～50 μM MMC for 30 hours. And also, the protective effect of N-methyl D-aspartate(NMDA) receptor antagonist, D-2-amino-5-phosphovaleric acid(APV) was examined by cell viability in these cultures. Cell viability was significantly decreased in dose dependently after exposure of 30 μM MMC to cultured osteoblasts for 30 hours. Protective effect of APV against MMC-mediated toxicity was very effective in these cultures. From above the results, it suggests that MMC is toxic in cultured mouse osteoblasts and NMDA receptor antagonist such as APV is effective in blocking the osteotoxicity induced by MMC.

• Journal of Physiology & Pathology in Korean Medicine
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• v.19 no.4
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• pp.1022-1026
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• 2005

To clarify the toxic effect on cultured neonatal mouse cerebral neurons damaged by ischemia, we examined the cytotoxicity induced by ischemia and the protective effect of antioxidant and AMPA/kainate receptor antagonist against ischemia-induced cytotoxicity on cultured cerebral neurons. For this study, mice were administrated with 20ug/kg cyclothiazide or 50U/kg vitamin E via intraperitoneal injection for 2 hours before ischemic induction. After cell culture for 7 days, cell viability, amount of neurofilament and protein kinase C activity were examined. Ischemia decreased significantly cell viability, amount of neurofilament and the increase of protein kinase C activity in these cultures. In the protective effect, vitamin I showed remarkably the increase of cell viability and amount of neurofilament, and the decrease of protein kinase C activity but, cyclothiazide did not showed any protective effect on ischemia-induced cytotoxicity. From these results, it is suggested that vitamin I is effective in blocking the neurotoxicity induced by ischemia, but cyclothiazide as a AMPA/kainate receptor antagonist is not.

• Restorative Dentistry and Endodontics
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• v.28 no.5
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• pp.409-418
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• 2003

본 연구는 치수 염증 시 IL-8과 MCP-1 분비에서 neuropeptide의 역할에 대해 관찰하고자 발거된 건전한 치아를 수직 파절시켜 치수조직을 채취하여 배양된 치수세포 및 혈관내피세포(ECV 304세포)를 각기 다른 농도의 Substance P(SP)로 12시간 자극하였고, 24시간 동안 4시간 간격으로 시간대별로 자극하였으며, 또 치수세포를 Calcitonin gene-related peptide (CGRP)로 12시간 자극하였다. 이들 세포를 SP길항제 (Spantide)로 15분간 차단한 후 SP로 12시간 재 자극하였으며, SP와 CGRP혼합액을 12시간 자극하였다. 상기의 실험 후 부유물로 ELISA를 시행하여 IL-8과 MCP-1의 분비 량을 측정하였다. 치수세포는 SP로 자극 시 IL-8이 현저히 증가한 반면, CGRP는 효과가 없었으며, SP와 CGRP를 혼합자극 시 시너지 효과 또한 없었고, Spantide는 치수세포의 IL-8과 MCP-1의 분비를 차단시켰다. 치수세포를 SP로 24시간 동안 4시간 간격으로 자극 시 8시간 후 최대의 IL-8은 분비량 나타내었으며, 8시간과 12시간 사이에서 최대의 MCP-1 분비량을 나타내었다. ECV 304세포를 SP로 자극 시 IL-8과 MCP-1 분비량이 미약하게 증가하였으며, Spantide는 ECV 304세포의 IL-8과 MCP-1 분비를 억제시켰다.

• Applied Microscopy
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• v.28 no.4
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• pp.591-601
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• 1998

The neurotoxic effects of radiation have been studied in NSC-34 hybrid cells derived from embryonic mouse spinal cord cells. NSC-34 cells irradiated at 25Gy were decreased the cell viability in a time and dose dependent manner. The decrease in cell viability induced by the irradiation was blocked by catalase. Antagonists of the N-methyl-D-aspartate (NMDA) receptor, including D-2-amino-5-phosphonovaleric acid (APV) and chlorokynurenic acid (CKA), similarly blocked radiational induced in cell viability. We performed morphological analysis of light and electron microscope. NSC-34 cells irradiated at 25Gy were decreased the cell density and increased lysosomes and vacuoles in the cytoplasm. Especially chromatin modification was observed. These results indicated that radiation was involved in the oxidant-initiated neurotoxicity and the compounds catalase, APV and CKA were shown to be neuroprotective against radiation.

• YAKHAK HOEJI
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• v.50 no.4
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• pp.278-286
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• 2006

Classical dihydropyrrole[3,4-f]quinazoline antifolates 7,8 and 9, in which the tricyclic ring is structurally similar to the pteridine ring of $CH_2-THF(1)$, the cofactor of thymidylate synthase (TS), were synthesized, and their in vitro antitumor activity was evaluated by measuring the cell growth inhibitory activity against cancer cell lines. The target compounds were cytotoxic against CCRF-CEM, human T-cell acute lymphoblastic leukemia, with the cell growth inhibitory activity $(IC_{50})$ of $0.8{\sim}8.3\;{\mu}M$. Among the three compounds, 3-amino analog 7 was 10- and 3.5-fold more cytotoxic compared to the 3-methyl analogs 8 and 9, and its cytotoxicity was similar to that of the reference compound with the $IC_{50}$ value of $0.83\;{\mu}M$. This result was supposed as the consequence of the fact that dihydropyrroloquinazolinone ring with amino group was able to bind well in the active site of TS. In the case of 3-methyl analogs, analog 9, which has two-carbon bridge between the dihydropyrroloquinazolinone ring and benzoyl-L-glutamic acid, was 3-times more potent in cytotoxicity than analog 8 which has one-carbon bridge, and this result indicates that the distance and conformational orientation of the benzoyl-L-glutamic acid moiety with respect to the tricyclic ring may also be a crucial determinant of cell growth inhibitory activity.