• The korean journal of orthodontics
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• v.26 no.5 s.58
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• pp.591-599
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• 1996

This study was undertaken to investigate the cytotoxicity of orthodontic wires after doing various treatments to the wires. 018x025 inch Stainless steel(A) and Co-Cr(B) wires were used and each of them were divided into 4 groups. A-1 and B-1 groups were as received state, and A-2 and B-2 groups were heat treated. A-3 and B-3 groups were electropolished after heat treatment, and A-4 and B-4 groups were soldered with Ag-solder. Each group had 3 wires and these were sterilized with Ethylene Oxide gas. We used human gingival fibroblast cell culture and agar overlay technique to investigate the cytotoxicity of each group of wires. The cytotoxicity of wire was assessed using reaction index (zone index/lysis index). The findings of this study were as follows. 1. Both of the stainless steel wire and Co-Cr wire showed no cytotoxicity in as received state. 2. Heat treatment or electropolishing of the wires had no effect on the cytotoxicity of the wires 3. Soldered stainless steel wires showed a little wider zone of discoloration than soldered Co-Cr wires, but the zone index and cytotoxicity(reaction index) was not different. 4. Soldered wires showed moderate cytotoxicity in both of the wires.

• Environmental Analysis Health and Toxicology
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• v.22 no.4
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• pp.305-312
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• 2007

환경오염을 신속하게 모니터링하기 위한 생물지표의 개발은 증가하고 있는 오염의 심각성에 비추어 매우 중요한 과제로 여겨지고 있다. 본 연구에서는 독성물질처리에 의하여 선택적으로 발현이 조절되는 단백질의 동정을 통하여 독성물질에 대한 단백질 생물지표를 발굴하고자 시도하였다. 즉, 송사리(Oryzias latipes)를 유기인계 살충제인 다이아지논(diazinon)에 0, 0.1, 1, 5 mg/L 농도로 24시간 노출시킨 후, 머리와 몸통부분으로 나누어 단백질 발현패턴을 분석하였다. 본 시스템에서 다이아지논 처리에 의하여 유의적으로 발현이 증가된 단백질로서 alpha-tubulin, ribonuclease pancreatic precursor, protein hfq 등을 동정하였으며, 이 가운데 alpha-tubulin과 $hsp90{\beta}$의 발현이 다이아지논 농도에 의존적으로 증가하는 것을 semi-quantitative RT-PCR방법으로 확인하였다. 이와 같이 다이아지논 처리에 특이적으로 발현이 증가된 송사리 단백질들은 노출평가를 위한 생물지표로서 개발에 응용될 수 있을 것으로 평가된다.

• YAKHAK HOEJI
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• v.17 no.2
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• pp.71-91
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• 1973

미생물의 대사산물은 극히 다양함으로 그중에는 암세포에 선택적으로 작용하여 증식을 억제하는 것이 있으리라는 예상하에서 종양을 이식한 동물을 사용하여 항암성 물질을 스크리-닝하기 시작한 것은 1951년경 부터였다. 그리하여 지난 20여년간에 200종 이상의 항종양성 물질이 보고되었고 그 화학구조는 가지 각색이다. 그간의 연구의 추세를 들이켜 본다면 초기에는 항종양작용에 중점을 두었기 때문에 독성이 강한 물질이 다소 보고되었으며 중기에는 조직배양을 이용했기 때문에 세포독 물질이 주축을 이루고 있다. 근래에는 독성이 낮은 물질, 특히, 고분자의 물질이 추구되고 있는 경향이다. 이미 보고된 200여종의 항종양성 항생물질중 실지로 쓰이고 있는 것은 10여종에 불과하다는 사실은 전신요법제로써의 항암제의 독어이 얼마나 중요한 가를 잘 증언해 주고 있다. 항종양성 항생물질은 화학구조, 생성하는 미생물, 작용기전 등에 분류할 수 있다. 그러나 화학구조가 다양하다는 점에서 또 생성하는 미생물은 대개 방성균류이라는 점에서 그리고 작용기전은 대개 핵산에 작용한다는 점에서 볼때 이러한 분류기준을 채택한다는 것이 특별히 유리한 점이 없는 것 같으므로 여기서는 편의상 발견된 연대순으로 나열하여 기재하기로 한다.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1997.11a
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• pp.19-25
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• 1997

Bicyclomycin(BCM)은 1972년에 일본 Hokkaido, Sapporo지방의 토양균중의 하나인 Streptomyces Sapporoneosis의 배양액으로부터 최초로 분리된 항생물질로서 특히 Gram(-) 박테리아인 Escherichia coli. Klebsiella, Shigella, Salmonella, Citrobacter, Enterobacter cloacae, Neisseria gonorrhoeae등에 대한 선택적인 항균효과를 가지고 있고 Streptomycin, Kanamycin, Chloramphenicol, Tetracyclin, Aminobenzylpenicillin 및 naldixic acid 등에 대해 교차내성을 가지고 있지 않다. BCM은 구조적인 면에서 [4.2.2]bicyclic구조를 가지고있는 특이한 항생물질로서 C(1)-triol부분, diketopiperazine부분 그리고 C(5)-C(5a)exomethylene의 3 부분으로 크게 나눌수 있다(Fig. 1). BGM은 E. coli에 대한 항균력으로서 250-500 $\mu\textrm{g}$/mL의 MIC value를 가지고 있고 급성독성으로서 LD$_{50}$가 4g/kg 이상으로 거의 독성이 없는 것이 특징이다. 현재 Fujisawa pharmaceutical Ltd.로부터 Bicozamycin이라는 상품명으로 설사치료제 용도로 시판되고 있다.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2001.05a
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• pp.131-131
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• 2001

내분비계장애물질에 대한 검색기법의 하나로 수컷 어류의 교배행위 및 생식력에 대한 in vivo 연구를 시도하였다. 수컷 송사리(Oryzias latipes)에 대표적 에스트로젠인 17$\beta$-estradiol를 2 및 20 $\mu\textrm{g}$/L의 농도로 각 노출군당 5마리씩 14일간 노출시킨 후 각 군당 임의로 2마리씩 선택하여 Prostaglandin F2$\alpha$를 주사한 3마리의 정상 암컷 송사리와의 교배행위를 비디오 카메라를 이용하여 1시간 동안 녹화하여 분석하였다. (중략)

• Environmental Analysis Health and Toxicology
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• v.22 no.3
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• pp.197-202
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• 2007

구리는 환경에 광범위하게 존재하며, 생물체에게 필수적인 무기질이지만 고농도로 존재할 경우 독성을 발휘한다. 본 연구는 프로티옴 기술을 응용하여 수서태계에 구리와 같은 중금속의 존재 여부를 신속하게 평가하기 위한 생물지표를 발굴하기 위하여 수행되었다. 즉, 송사리(Oryzias latipes)를 이용하여 여러 농도의 구리용액(0.1, 1, 5 mg/L)에 24시간 노출시킨 다음, 머리부분에서 선택적으로 발현이 증가되는 단백질을 동정하고자 시도하였다. 본 시스템에서 유의적으로 발현이 증가하는 것으로 나타난 단백질은 beta-tubulin, heat shock cognate 70 (hsc70)이었으며, 이 결과의 일부를 semi-quantitative RT-PCR를 이용하여 확인하였다. 이와 같이 구리 처리에 특이적으로 발현이 증가된 송사리 단백질들은 노출평가를 위한 생물지표로서 개발을 위하여 더 연구할 가치가 있는 것으로 평가된다.

• Economic and Environmental Geology
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• v.34 no.4
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• pp.417-422
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• 2001

Sutfactants may be used in remediation of subsoil and aquifer contaminated with hydrophobic compounds. The objectives of this study were to select potentially suitable sUlfactants that solubilize toluene present as a contaminant and to determine the effectiveness of toluene removal from Ottawa sand by the selected surfactants. Material used as the model soil was Ottawa sand and the organic used as model contaminant was toluene. Used experimental methods were separatory funnel experiment and shaker table agitation/centrifugation experiments. Based on the experimental results, the following conclusions were drawn; t) In the surfactant selection, six different surfactants were chosen based on surfactant types, toxicity, and water solubility. These six were focused into two on the basis of HLB and surface tension study, separatory funnel experiment, shaker table and centrifugation experiments. The two most suitable surfactants were Sandopan JA36 (an anionic surfactant), and Pluronic L44 (a non-ionic surfactant). 2) In the shaker table agitation and centrifugation experiments, the highest recovery of the toluene was 96% which was obtained with one surfactant wash plus two water rinses using an anionic surfactant (Sandopan JA36).

• The Journal of the Korea Contents Association
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• v.11 no.3
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• pp.293-301
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• 2011

The material of the dental prosthesis was required bio-compatibility for biological, chemical, and physical stabilities. This study was conducted the stability evaluation of mechanical, biological characteristics through comparing Co-Cr alloy(SC group), Ti alloy(ST group) made by the selective laser melting method with Co-Cr alloy(CC group), Ni-Cr alloy(CN group) made by the casting method. Modulus of elasticity for mechanical characteristic evaluation was measured by the tensile test. And we conducted the release material analysis using lactic acid-NaCl solution for the evaluation of biological stability and were observed cytotoxicity through the content of this release medium. Taking these results into account, the Co-Cr alloy made by the selective laser melting method was observed modulus of elasticity higher than he Co-Cr alloy made by the casting method. And the Co-Cr alloy made by the selective laser melting method had more superior biological stability than the other groups as the result of cytotoxicity evaluation through the release material analysis. By this results, we think that alloys made by the selective laser melting method can be applied as materials for making the dental prosthesis.

• The Korean Journal of Pesticide Science
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• v.12 no.3
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• pp.249-255
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• 2008

The comparative toxicity of recommended rates of three acaricides, fluacrypyrim, cyflumetofen and spiromesifen to the predatory mite, Neoseiulus womersleyi and its prey, Tetranychus urticae was bioassayed in the laboratory. Fluacrypyrim and cyflumetofen were much less toxic to adult females of N. womersleyi than to those of T. urticae. Adult female predators treated with these two acaricides produced $88{\sim}93%$ as many eggs as did control females. Fluacrypyrim and cyflumetofen did not affect the hatch of N. womersleyi eggs or the development of surviving immature predators, and $92{\sim}96%$ of immature predators reached adulthood. Spiromesifen at its treated concentration did not significantly affect the survival and reproduction of adult female predators but caused 100% mortality in larvae of N. womersleyi. Adult female predators survived on a diet of spider mites treated with fluacrypyrim and cyflumetofen, and their fecundity was not significantly affected. Moreover, immature predators developed normally on prey treated with these two acaricides. The results indicate that fluacrypyrim and cyflumetofen are promising candidates for use in integrated mite management programs where N womersleyi is the major natural enemy.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.143-149
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• 2006

A extract from Spirulina platensis of seawater and freshwater was obtained by using the water and ethanol. Extraction yields of seawater S. platensis were observed about 3% higher than freshwater S. platensis. Cytotoxicity (HEK293) and inhibition ratio of cancer cell line (A549, AGS, MCF7, Hep3B) in adding of the extracts from the S. platensis of seawater and freshwater were measured by SRB assay. Cytotoxicity of all of the extracts in adding 1.0 mg/ml was below 26%. Ctotoxicity of the extracts from the seawater S. platensis were about 6% less than freshwater S. platensis. Inhibition ratio of cancer cell growth was inhibited by adding 1.0 mg/ml of the extracts that was obtained about 80%. Inhibition effect of cancer cell growth in adding seawater S. platensis was observed higher than freshwater S. platensis. Differentiation ratio of HL-60 cells in adding the extracts of seawater S. platensis was observed highly that was 160.9%.