• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.4
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• pp.2189-2198
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• 2014

Paraquat (PQ) is a very effective and widely used herbicide that was commercially introduced in 1962. In this study, instead of using antioxidants like in the past, to inhibit the formation of PQ-induced ROS, we attempted to reduce the oxygen concentration by using non-lethal hypoxia therapy. Therefore, we studied the toxicity of PQ in vivo, analyzed the major effects of ROS on the targeted lung tissue and compared the results with the gross histological changes after the cell protective effect of non-lethal hypoxia therapy. In vivo studies demonstrated that low-concentration oxygen therapy (i.e., 10-12% oxygen) in rats administered with PQ was associated with a higher survival rate than in rats that received only PQ. In vivo non-lethal hypoxia treatment showed better survival and less lung tissue damage. Using a hypoxic/anaerobic incubator with integrated multifaceted molecular analysis, including MDA assay, glutathione assay, and SOD assay, we established an optimal, significantly reduced in vivo non-lethal hypoxia treatment by exploiting the PQ-induced cytotoxicity responses.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.42.1-42.1
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• 2010

Poly-carprolactone (PCL)은 생분해성 고분자로 장기간의 임상실험 결과 생체에 독성이 없으며 생체친화성이 우수한 소재로 확인되어 PLGA, PLLA 등과 더불어 조직공학 분야에서 널리 사용되고 있는 생체재료이다. 그러나 PCL은 5개의 비극성 methylene group과 1개의 극성 ester group이 반복되는 지방족의 polyester로 구조상 탄소수가 많아 소수성을 띄는 단점을 가지고 있다. 이러한 표면이 소수성인 재료의 경우, 초기 단백질 흡착능이 떨어져 세포의 부착이 느린 속도로 일어나므로 세포 분화 및 조직 재생이 더디게 일어난다. 본 연구에서는 소수성의 PCL 표면의 단백질 흡착능을 증가시키기 위해 기능성 amine group을 부착하였으며, 또한 골재생을 촉진시킬 수 있는 세포외 기질인 collagen과 osteopontin을 부착함으로써 고기능성 PCL membrane을 제조하였다. 제조된 PCL membrane은 골재생용 조직공학에의 응용을 위해 지방유래 줄기세포를 이용하여 부착능 및 골세포로의 분화능을 확인하였다. 표면 성질의 변화에 의한 세포의 부착능의 변화를 confocal microscopy을 이용하여 부착에 관여하는 단백질의 발현을 확인하였으며, collagen과 osteopontin에 의한 골세포로의 분화능을 확인하기 위해 real time PCR을 통해 골세포의 분화 표지 유전자의 발현을 비교 분석하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2019.11a
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• pp.268-268
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• 2019

The purpose of this study is to understand the risk of chemical product, Styrene Monomer(SM), shipped in a vessel. SM is harmful chemical product which can make injury, explosion and/or fire in a vessel. The understand of SM risk is very important to protect seafarer's body and vessel safety. This research can be expected that the understanding of SM risk by a seafarer's to prevent accidents by SM explosion and/or fire.

• Journal of Environmental Health Sciences
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• v.45 no.3
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• pp.285-294
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• 2019

Objectives: For suitable risk management of the domestic aquatic environment, it is necessary to conduct toxicity tests using species native to Korea. In the present study, we performed toxicity ring tests using endemic freshwater arthropoda Neocaridina denticulata and evaluated its validity and reproducibility as an international standard test species. Methods: To evaluate the sensitivity levels of N. denticulata to hazardous chemicals, toxicity values for several chemicals were compared with other standard test species. Intra- and inter-laboratory acute toxicity tests were performed both within a single laboratory and among four laboratories respectively using 3,4-Dichloroaniline, which is generally used as a reference test substance in fish toxicity tests. In addition, intra- and inter-laboratory coefficient of variations (CVs) were calculated to evaluate reproducibility based on the estimated toxicity values. Results: The sensitivity of N. denticulata to several chemicals was found to be similar with D. manga, indicating that the species is valid as a test species. The CVs of the intra- and inter-laboratory tests were 22.946% with four qualified runs and 8.828% among the four laboratories, respectively. Conclusions: N. denticulata serves in an important role in the food chain of Korean aquatic ecosystems and also inhabits several other Asian countries. Since the validity and reproducibility of the species were confirmed as a toxicity test species in this study, further efforts are needed to establish N. denticulata as the international standard test species for the appropriate risk assessment of aquatic ecosystems at home and abroad.

• Korean Journal of Environmental Biology
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• v.34 no.3
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• pp.183-192
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• 2016

Silver nanomaterials have been intensively applied in consumer products of diverse industrial sectors because of their strong biocidal properties and reported to be hazardous to aquatic organisms once released in the environment. Nanomaterials including sliver, are known to be different in toxicity according to their physicochemical characteristics such as size, shape, length etc. However studies comparing toxicity among silver nanomaterials with different physicochemical characteristics are very limited. Here, toxicities of silver nanomaterials with different size (50, 100, 150 nm), length (10, $20{\mu}m$), shape (wire, sphere), and coating material (polyvinylpyrrolidone, citrate) using OECD test guidelines were evaluated in aquatic species (zebrafish, daphnia, algae) and compared. On a size property, the smaller of silver nanomaterials, the more toxic to tested organisms. Sphered type of silver nanomaterials was less toxic to organisms than wired type, and shorter nanowires were less toxic than longer ones. Meanwhile the toxic effects of materials coated on silver nanomaterials were slightly different in each tested species, but not statistically significant. To the best of our knowledge, it is first investigation to evaluate and compare ecotoxicity of silver nanomaterials having different physicochemical characteristics using same test species and test guidelines. This study can provide valuable information for human and environmental risk assessment of silver nanomaterials and guide material manufacturers to synthesize silver nanomaterials more safely to human and environment.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2020.08a
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• pp.83-83
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• 2020

염증은 물리화학적 자극이나 세균 감염과 같은 외부 자극에 대응하기 위한 생체조직의 방어 반응의 하 나이며 조직이나 장기의 손상을 회복시키는 기전으로서 매우 중요한 역할을 하지만 염증반응이 과도해 질 경우 궤양성 대장염, 기관지염, 천식, 대장암 등을 유발하는 원인으로 작용하기 때문에 염증반응을 조 절하는 항염증제 개발은 매우 중요시되고 있다. 국내 염증개선 관련 시장은 현재 약 3조원 규모이며 지속 적인 성장세에 있지만 천연소재의 기능성 중심으로 출시된 제품 중 다수의 제품에서 주로 수입 원료를 사용하고 있어 국내 자생 및 재배하는 천연 소재들의 효능에 대한 검증을 통해 수입 원료 의존도를 낮추 기 위한 연구가 요구되고 있다. 따라서 본 연구에서는 순창에서 재배되는 참두릅 (Aralia elata Seem)과 도라지 (Platycodon grandiflorum)를 이용하여 천연 염증개선 소재화를 목적으로 기능성 증진을 위한 추 출조건 선정과정과 대식세포에 대한 세포독성 및 항염증 효능을 확인하여 천연소재를 이용한 염증개선 소재화를 시도하고자 한다. 본 연구는 전북 순창에서 재배되는 참두릅과 도라지의 추출조건을 선정하기 위해 용매, 온도 및 시간별 추출물의 total polyphenol 함량 평가를 통하여 최적 추출조건 선정을 진행하 였으며, 선정된 추출조건에서 추출된 추출물의 항산화 활성을 측정하기 위하여 DPPH & ABTS radical scavenging activity 및 total flavonoids 함량을 확인하여 항산화 효능을 평가하였다. 또한 대식세포인 Raw 264.7을 사용하여 MTT assay, Nitric oxide (NO) 생성 억제 효능을 확인하여 세포독성 및 항염증 활 성을 평가하였다. 실험결과, Total polyphenol 함량 분석을 통해 최적 추출조건이 선정된 두릅 (주정 40%, 25℃, 3 h), 도라지 (주정 60%, 25℃, 1 h)의 추출물을 이용하여 DPPH & ABTS radical scavenging activity 및 total flavonoids 함량을 분석한 결과, 도라지보다 두릅에서 더 높은 항산화 활성을 나타내었다. 대식세포를 활용한 두릅과 도라지의 세포독성을 측정한 결과, 100 ug/mL 이내의 농도에서 독성활성이 나타내지 않음을 확인되었으며, 항염증 활성을 측정한 결과 100 ug/mL에서 두릅 추출물이 도라지 추출 물보다 약 33% 이상 NO 생성억제 활성이 높게 나타내었다.

• Korean Journal of Environmental Agriculture
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• v.30 no.3
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• pp.316-322
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• 2011

BACKGROUND: Pesticides concentration was monitored in 50 agricultural lakes, and ecological risk for aquatic organism was assessed using risk quotient (RQ) and probabilistic methods. METHODS AND RESULTS: Pesticides concentrations detected in 50 agricultural lakes during peak season (June and September) were in the range of $0.17{\sim}0.99{\mu}g/L$. The RQ for algae and the other species was estimated to be 0.25 and below 0.01, indicating medium risk and no risk. Oxadiazon predominantly contributed to RQ value of 99% for algae, fishes, and amphibians. In terms of hazardous concentration at 5% of species ($HC_5$), ecological risk quotients (ERQ) for oxadiazon ranged from 0.18~0.33, showing a medium risk level. Overall, the concentrations of pesticides were much lower than $HC_5$), value. Probability of combined ecological risk for pesticides ranged from 1.82% to 2.41%. CONCLUSION(s): Combined ecological risk probability did not exceed the acceptable level of 5%, indicating no ecological risk for selected aquatic species. This study suggests that regular ecological risk assessment (ERA) will be required to protect and manage an agricultural lake. Not only ERA at screening level by comparing exposure with toxic effects for aquatic species also advanced ERA technique considering species in indigenous to Korea, chronic toxicity, pulse dose, fate, and environmental factors should be required.

• Journal of Acupuncture Research
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• v.24 no.2
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• pp.73-81
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• 2007

목적 : 본 연구는 화피의 연골 보호 및 소염 진통 작용을 알아보고, 화피를 이용한 관절염치료 약침액 개발의 기초자료를 얻기 위해 고안되었다. 방법 : In vitro에서는 토끼 무릎관절에서 배양된 연골조직에 5ng/ml IL-1${\alpha}$ 처리 후， 화피의 연골보호 효과, 연골세포에 대한 독성을 조사하였다. In vivo에서는 토끼 무릎관절내 collagenase를 주입, CIA 유발 후, 28일간 매일 토끼의 구강으로 화피, 증류수, CEX를 투여하였으며, 연골보호, 소염, 진통에 대한 측정을 하였다. 결과 : 화피는 proteoglican 및 collagen분해 억제, MMPs 활성 억제로 연골 보호 효과가 있었으며, 연골 세포에 대한 독성이 없었다. 소염작용은 PGE2 생산 억제 및 COX-2발현 억제, carrageenan 유발 쥐 모델에서의 부종 억제로 확인되었다. 진통작용은 tail flick test에서의 latency time 증가, formalin test에서의 염증성 통증억제로 나타났다. 결론 : 화피가 퇴행성관절염에 대한 연골 보호 효과 및 소염 진통 작용이 있으므로, 이를 근거로 약침액을 개발 응용하면 퇴행성관절염 치료에 활용될 수 있다고 사료된다.

• Journal of Food Hygiene and Safety
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• v.16 no.1
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• pp.21-26
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• 2001

Risk assessment traditionally are conducted on individual chemicals; however, humans are exposed to multiple chemicals in daily life. The organophosphorus (OP) pesticides are considered in a single risk assessment because they act by a common mechanism of toxicity, and there is likely to be expose to multiple OP pesticides simultaneously or sequentially. The OP pesticides act by inhibiting the enzyme acetylcholinesterasc (AChE) and have available extensive database. AChE is widely distributed throughout the body, most importantly in the nervous system. Inhibition of AChE results in accumulation of acetylcholine in the nervous system that results in clinical signs of cholinergic toxicity, including increased salivation and lacrimation, nausea and vomiting, muscle fasciculation, lethargy and fatigue, among others. To conduct an exposure assessment for pesticides in the diet, we need to know the food consumption patterns of the populations, and the pesticide residue levels in the foods that are consumed. This study was conducted to identify cumulative dietary risk due to multiple OP pesticides that can be exposed through various foods. Total 22 food samples including cereals, vegetables and fruits were collected randomly two times from food markets in several sites (4 cities). The subjected foods were selected by regarding of highly consumed foods to general Korean people. The 12 OP pesticides including Acephate, Azinphos-methyl, Chlorpyrifos, and Diazinon were monitored. For the exposure assessment, general adult group of 60 kg body weight was regarded as target population and food consumption data suggested by Lee et al. (2000) were used as consumed value of individual food. Analyses of samples for OP pesticides have been carried out according to the multiclass multiresidue analysis method and acephate and methamidophos analysis method of Korea Food Code. In general the levels of OP pesticides found in the food samples were very low or not detected.

• Proceedings of the KOR-BRONCHOESO Conference
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• 1987.05a
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• pp.9.2-9
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• 1987

외래에서 고막에 대한 간단한 수술을 시행함에 있어 고막의 국소 마취법으로 iontophoresis(전기 영동법)은 오래 전부터 널리 시행되어 왔으나 와우나 전정신경계에 대한 독성 때문에 논란의 대상이 되어 왔다. 1973년 Comeau이후 여러 학자에 의한 일련의 동물 및 인체 실험결과 lidocaine 의 iontophoresis는 안전하고 효과적인 방법으로 실제 임상에서의 사용을 권장하고 있으며 근년 널리 이용되고 있으나 iontophoresis를 시행함에 있어 기구 자체의 금속성 물질에 의한 독성 및 사용 약물의 내이 침투에 의한 영향에 관해서는 아직도 많은 연구가 진행되고 있다. 저자들은 1983년 부터 1986년 12월까지 고려병원 이비인후과에서 고막절개를 위해 iontophoresis에 의한 lidocaine의 국소마취법을 시행받은 환자중 무작위로 추출한 39명(46이)을 대상으로 iontophoresis시행 전후의 청력상의 변화에 관한 청각학적 고찰을 시행하여 iontophoresis후 청력 역치에 유의한 변화가 나타나지 않는다는 결과를 얻었다.