• Environmental Analysis Health and Toxicology
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• 제24권3호
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• pp.181-191
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• 2009

As an effort to prevent serious accidents involving oxygen deficiency and suffocation in confined spaces and to identify the causes of such accidents, the present study investigated relevant accidents and systems in Korea and other countries. This study also conducted a number of experiments at lethal concentration levels of oxygen deficiency using SD rats and observed the changes of experimental animals with humidity, organic gas (toluene), hydrogen sulfide, carbon monoxide and so on at the oxygen deficient environment. The results of the study are as follows. 1. The results from the experiment conducted using SD rats at lethal concentration levels of oxygen showed that there were no casualties at the 7% oxygen concentration level, but the mortality increase to 20% at 6% oxygen, it was jumped to 90% at 5% oxygen, and it was also dramatically reached 100% at 4% oxygen concentration. Therefore, 5.5% was calculated as the $LC_{50}$ (rat, 4hr) from these dose-response experiments with oxygen deficiency. 2. When we changed the level of toluene, $H_2S$, CO, humidity, and so on, in an oxygen deficient environment, it was observed that the small concentrations of $H_2S$ and CO make the highest effect on animals. In case of 350 ppm $H_2S$, it resulted in 30% mortality, and the 100% mortality was shown in 1,200 ppm CO concentration. The mortality increased as an oxygen deficient condition. However in the case of toluene up to 1,000 ppm, it were not affected with oxygen deficiency, and it did not indicate any significant differences in mortality as 20%, 90% humidities.

• 한국수산과학회지
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• 제38권2호
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• pp.100-105
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• 2005

Two species of fish and five species of marine invertebrate showed different tolerances to the toxicity of composite slag and bituminaus coal. Especially, Hemicentrotus pulcherrimus and young Haliotis discus hannai displayed marked differences in tolerance from. H. pulcherrimus and young H. discus hannai showed lethal effects at higher concentrations than those concentrations of the composite slag in the 1.0 and $0.4\%$ range, respectively. H. pulcherrimus showed no lethal effects at a lower concentration of $1.0\%$ composite slag and some differences in the rate of oxygen consumption with this concentration of composite slag. The lethal effects of bituminous coal on marine and fisheries organisms, even with higher concentrations, were not observed. At a higher concentration than that of 500 mg/L (ppm) of bituminous coal, decrease effects appeared in the rate of oxygen consumption of the experimental organisms. Taking into consideration that the experimental concentration of composite slag and bituminous coal were impracticable in the ocean, the results of this experiment suggest that composite slag and bituminous coal pose no real threat to marine or fisheries organisms.

• 한국가스학회지
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• 제17권4호
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• pp.18-25
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• 2013

맨홀 또는 환기가 부족한 공간에서 작업 중 유해 가스나 산소결핍에 의한 질식 또는 급성중독에 의한 건강장해나 사망사고가 빈번히 발생되고 있다. 따라서 유해가스에 의한 급성중독이나 산소결핍에 의한 유해농도 규명과 재해발생시 원인규명 자료로 활용하고자 산소결핍과 유해가스 노출에 따른 사망농도 시험하고자 하였다. 특히 산소결핍 상황에서 유해가스의 영향에 대해서도 시험하였으며, 국내외에서 발생된 관련 각종 사고 사례 조사를 통하여 동종재해를 예방하고자 하였다. 자료를 조사한 결과 산소결핍 또는 유해가스 노출에 의한 사망 재해는 하절기(6-8월)에 전체의 50%가 발생하고, 업종은 건설업 40%, 장소는 맨홀 50%, 원인은 산소결핍이 가장 많았으며(40%), 기타 가스($H_2S$, CO, $N_2$, Ar 등) 및 환경적 요인(내부 온도, 바닥 물 익사)도 크게 작용하였다. 동물실험 결과 산소결핍에 의한 치사 산소농도는 5%수준이었으며 Dose-Response의 통계처리결과 과반수치사농도 $LC_{50}$(rat, 4hr)는 5.5%로 산출되었다. 또한 산소결핍(6%수준) 상황에서 다른 유해물질이 혼합 될 경우 미치는 치사농도 시험 결과 $H_2S$ 20 ppm에서 40%치사, CO는 600 ppm에서 20%치사, 톨루엔은 1,000 ppm에서도 사망 예가 증가하지 않았다. 즉, $H_2S$, CO 등은 치사농도에 민감하게 반응하는 유해물질로의 상승작용을 했다.

• 한국어병학회지
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• 제20권2호
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• pp.161-167
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• 2007

평균체중 96 ± 3.6 g (평균전장 43 cm)의 극동산 뱀장어 (Anguilla japonica)에 대한 포르말린의 급성독성 실험 (수온 27～28℃, pH 7.4, 용존산소량 5.6 ppm)을 실시하였다. 특히 이 시험은 뱀장어에서 Pseudodactylogyrus 구제를 위해 포르말린을 사용할 때 치료농도에서 뱀장어가 안전한가를 평가하기 위해서 수행하였다. 포르말린 농도별 (0～500 ppm) 침지 후, 500 ppm에서는 10시간째, 400 ppm에서는 24시간째 전 실험어가 사망하였다. 24시간 경과한 후 300 ppm에서는 96.6% 그리고 200 ppm에서는 13.3%의 누적사망률을 각각 나타내었다. 그러나, 100 ppm에서는 24시간 동안 실험어가 모두 생존하였다. 뱀장어에 대한 포르말린의 24시간-LC50은 269 ppm으로 나타났다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제8권1호
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• pp.37-40
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• 2003

The antibacterial action of violet pigment, a mixture of violacein and deoxyviolacein, isolated from phychrotrophic bacterium RT102 strain was examined, and the operational conditions for the effective production of violet pigment were studied. The antibacterial activity of the violet pigment was confirmed for several bacteria such as Bacillus licheniformis, Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, and Pseudomonas aeruginosa, and the high concentration of violet pigment, above about 15mg/L, caused not only growth inhibition but also death of cells. The growth properties of RT102 strain were clarified under various incubation conditions such as pH, temperature, and dissolved oxygen concentration. The maximum violet pigment concentration, i.e. 3.7 g/L, and the maximum productivity of violet pigment, i.e. 0.12 g .L$\^$-1/H$\^$-1/, were obtained in a batch culture of pH 6, 20$^{\circ}C$, and 1 mg/L of dissolved oxygen concentration.

• 한국산학기술학회논문지
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• 제15권4호
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• pp.2189-2198
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• 2014

본 연구는 제초제 음독 중에서 가장 치명률이 높은 파라쿼트 중독의 독성 감소를 위하여 파라쿼트 독성 기전으로 알려진 파라쿼트 유도성 활성산소종을 감소시키기 위해 기존의 항산화제들 치료제와는 달리, 사전에 산소 농도를 줄여서 파라쿼트에 의한 활성 산소종 발생 자체를 줄이는 저농도 산소요법의 유용성을 연구하였다. 이를 위해 백서를 활용하여 생존률 및 파라쿼트에 의한 활성 산소종의 영향을 가장 빠르고 많이 받는 폐조직의 육안적 조직학적 변화를 비교 분석함으로써 세포 독성 상황에서 저농도 산소요법의 효과를 분석하였다. 그 결과 저농도 산소요법을 처리한 군에서 유의한 생존률 증가와 함께 H&E Stain결과에서는 염증세포 증가 및 Aveolar space에 부종 소견이 저농도 산소요법을 함께 시행한 군에서 완화된 소견을 확인할 수 있었다. 또한 파라쿼트의 독성기전의 핵심인 산화스트레스발생 분석을 시행한 결과, MDA assay, Glutathione assay 및 SOD Assay모두에서 파라쿼트는 산화스트레스를 증가하지만 파라쿼트와 함께 저농도 산소요법을 처리한 경우 산화 스트레스가 감소함을 증명하였다. 이를 통해 본 연구는 임상에서 파라쿼트 중독에 대한 새로운 치료 대안으로서의 기초 연구로서 활용이 기대된다.

• 한국수산과학회지
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• 제28권3호
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• pp.373-381
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• 1995

유용 해산어류에 대한 산소소비 경향을 파악하기 위하여 넙치 Paralichthys olivaceus, 자주복 Takifugu rubripes, 조피볼락 Sebastes schlegeli, 농어 Lateolabrax japonicus, 참돔 Pagrus major, 감성돔 Acanthopagrus schlegeli 등 6종의 추어를 주대상으로 수온별, 밀도별, 체중별 산소소비량및 치사산소량에 관한 실험을 실시하였다. 모든 어종에서 산소소비량 $(Oc,\;ml/kg\;\cdot\;hr)$은 수온$(T,\;^{\circ}C)$의 상승에 비례하여 증가하였으며, 그 경향은 다음과 같은 회귀직선식으로 표시되었다. 넙치= Oc=34.0515T-339.5987 $(r^2=0.9730)$, 자주복. Oc=34.4941T-479.8732 $(r^2=0.9483),$, 조피볼락: Oc=44.7970T-634.2627 $(r^2=0.9718),$, 농어: Oc=26.1488T-318.0633 $(r^2=0.9316),$, 참돔: Oc=61.1020T-722.8926 $(r^2= 0.9805),$, 감성돔: Oc=75.1460T-947.9370 $(r^2=0.9392).$. 어체의 수용밀도가 증가함에 따라 단위체중당 산소소비량은 감소하는 경향을 보였다. 넙치는 체중(W, g) 증가에 파라 산소소비량이 감소함으로써 Oc=2532.0268W-0.6565 $(r^2=0.9229)$의 관계를 나타냈다. 넙치, 조피볼락, 자주복, 참돔의 치사산소량은 각각 0.66, 0.79, 0.75 및 1.36m1/1였다

• 약학회지
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• 제41권1호
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• pp.99-104
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• 1997

In order to elucidate the cytotoxic effect of oxygen radicals on cultured spinal dorsal root ganglion(DRG) neurons derived from mouse. the neurotoxic effect of oxygen radicals w as examined after cultured DRG neurons were exposed to xanthine oxidase(XO) and hypoxanthine(HX)-oxygen radical generating system. In addition. neuroprotective effect of epidermal growth factor(EGF) against oxidant-induced neurotoxicity was also evaluated in these cultures. The results were, as follows: 1. Lethal concentration 50(LC$_{50}$) was 35mU/ml XO and 0.1mM HX in cultured DRG neurons. 2. Oxygen radicals induced the morphological changes such as the decrease of cell number and loss of neurites in these cultures. 3. EGF increased the cell viability and neurofilament in neurons damaged by oxygen radicals. From above the results, it is suggested that oxygen radicals have a cytotoxic effect on cultured DRG neurons of neonatal mouse and selective neurotrophic factors such as EGF are, effective, in blocking the neurotoxicity induced by oxygen radicals in cultured spinal DRG neurons.

• 동의생리병리학회지
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• 제16권2호
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• pp.262-266
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• 2002

In order to elucidate the mechanism of cytotoxic effect of oxygen radicals on cultured mouse spinal motor neurons, the neurotoxicity induced by hydrogen peroxide(H₂O₂) was evaluated by MTT assay. The neuroprotective effect of Rhizoma Gastrodiae(RG) against H₂O₂-mediated neurotoxicity was also examined in these cultures by SRB assay. The results were as follows : The value of lethal concentration 50(LC50) of H₂O₂ was estimated at a concentration of 30 uM in these cultures. Cell viability of cultured mouse spinal motor neurons was remarkably decreased by H₂O₂-induced neurotoxicity in a dose- and time-dependent manner. RG was remarkably effective in blocking the neurotoxicity induced by H₂O₂ at a concentration of 120 μM as determined by SRB assay. From above the results, it is suggested that H₂O₂ induce neurotoxicity, and the selective herbal extracted RG was very effective in blocking H₂O₂-mediated neurotoxicity on cultured mouse spinal motor neurons.

• 한국수산과학회지
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• 제53권5호
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• pp.725-732
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• 2020

The sudden drop of water temperature in winter is very threatening factor that affects the productivity of farmed fish and the management in aquafarm. In this study, we investigated the effect of low temperature on the survival, oxygen consumption and stress responses of parrotfish Oplegnathus fasciatus due to acute drop of water temperature. The survival rate of parrotfish Oplegnathus fasciatus was 5% at 6℃, 95% at 8℃ and 100% at 10℃ on the 4^th day of exposure in each experimental temperature. Low-lethal temperature for 4days of parrotfish Oplegnathus fasciatus (4 day-LT₅₀) was 6.99℃ (confidence limit, 6.55-7.42℃). Oxygen consumption rate was significantly decreased with decreasing water temperature. Temperature coefficient (Q₁₀) was found to be 4.0 between 10℃ and 8℃ and 0.39 between 8℃ and 6℃. As a result of investigating the stress response according to the drop in water temperature, the concentration of SOD (Superoxide dismutase), cortisol, glucose, total Ig, AST (Aspartate) and ALT (Alanine aminotransferase) increased with decreasing of water temperature. This study would be useful for the management of temperature about cultured fish.