• Korean journal of applied entomology
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• v.55 no.3
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• pp.267-275
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• 2016

Chlorine dioxide has an insecticidal activity via its production of reactive oxygen species (ROS). Its cytotoxic activity has been regarded as a main cause of the insecticidal activity. This study tested a hypothesis that cytotoxicity of chlorine dioxide is resulted from its induction of apoptosis against target cells using ROS. Injection of chlorine dioxide significantly reduced total hemocyte counts of Plodia interpunctella larvae and subsequently killed the larvae. To analyze the cytotoxicity with respect to apoptosis, terminal deoxyribonucleotidyl transferase nick end translation (TUNEL) assay was performed. An insect cell line (Sf9) cells were exposed to different concentrations of chlorine dioxide. TUNEL assay showed that chlorine dioxide induced significant apoptosis of Sf9 cells in a dose-dependent manner. When different concentrations of chlorine dioxide were injected to larvae of P. interpunctella, it showed a dose-dependent induction of apoptosis against hemocytes. However, addition of vitamin E significantly suppressed the apoptosis induction and insecticidal activity of chlorine dioxide in a dose-dependent manner. These results suggest that cytotoxicity of chlorine dioxide is resulted from its induction of apoptosis against insect cells using ROS.

• The Journal of Korean Society of Virology
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• v.26 no.1
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• pp.23-30
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• 1996

대략 36,000 base pairs (bp)의 두 가닥짜리 DNA를 지놈으로 가진 사람 아데노바이러스 (Ad)는 DNA 상동성(相同性) 및 생물학적/생화학적 성격이 특이한 49개의 혈청형이 알려져 있는데, 이들 대부분의 Ad가 영유아군 및 면역능이 저하된 성인에서 치사적 결과를 초래할 수 있다. Ad의 세포향성(向性)(tropism)은 매우 다양하여 종류에 따라 상기도 감염, 각결막염, 영유아 장염등을 유발하는데 최근 Ad의 다양한 병원성에 대한 원인을 분자생물학적 수준에서 규명하려는 노력의 일환으로 지역에 따라 주되게 출현하는 Ad형 규명이 활발히 이루어지고 있다. Ad 동정/확인은 표면을 이루고 있는 group 공통항원인 hexon 단백질을 탐지하는 효소면역 측정법 (EIA)에 의하며, Ad형별은 Ad fiber의 세포독성 중화시험에의 한다. 그러나, 세포독성 중화시험이 엄청난 노동력 및 시간을 요구하면서도 민감도/특이도가 만족스럽지 못하여 이를 개선하기 위하여 검체 또는 세포배양에서 Ad DNA를 추출하여 제한효소 절단형태를 비교하는 방법이 개발되었는데 이는 세포배양에 잘 자라지 않는 바이러스주의 형별뿐만 아니라 지역 분리주들의 지놈 변형주를 관찰하는 분자생물학적/분자역학적 연구에도 도움이 되고 있다. 국내에는 Ad와 관련된 소아장염의 빈도가 rotavirus에 의한 것 다음으로 빈번한데도 Ad40/41외에 주되게 출현하는 장내 Ad형들이 전혀 규명된 바 없고, 한국형 Ad들의 지놈형태가 전혀 보고된 바가 없다. 또한 세계적으로 Ad형별 조사지역이 늘어감에 따라 유아장염과 연관된 Ad 역시 Ad40, 41이 외의 형들이 Ad40, 41을 능가하는 것으로 보고되고 있는 지역도 있으나 국내에서는 Ad40, 41이외의 형들은 그 역학적 중요도가 전혀 알려져 있지 않다. 이로서 본 연구의 목적은 Ad주들에 특이 중화항체를 이용한 세포독성 중화시험과 Ad DNA 절단법을 적용하여 한국형 장내 Ad주들의 형별을 처음으로 시도함과 동시에 1989-1991사이 출현한 Ad들의 유전적 변형을 관찰하려는 것이었다. 두 방법 모두 사용하였을 때 주되게 출현하는 장내 Ad형들은 Ad4l, Ad2, Ad7, Ad5, 및 Ad40이었다. Ad40/41-양성 검체를 제외한 Ad hexon-EIA양성들의 77.5%를 형별 할 수 있었던 Ad DNA의 제한효소 절단방법은 형들간의 교차중화로 특이성이 낮았던 중화방법 (47.5%)보다 매우 효율적이어서 두 가지 방법을 함께 적응하였을 때는 40주중의 81.5%인 35주를 형별 할 수 있었다. 또한Ad DNA 제한 효소 절단방법은 Ad7 변이주 (Ad7b)도 탐지 할 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.5
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• pp.527-533
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• 2007

The present study was carried out to investigate the potential toxicity of highly-developed rice varieties, Oryza sativa cvs. Jukjinjubyeo, Heuginjubyeo and Heughyangbyeo by a single oral dose in ICR mice. The test article was orally administered once by gavage at dose levels of 0, 2.5, 5.0, and 10.0 g/kg body weight (n=10 for male and female mice for each dose). We examined the number of deaths, general clinical signs, body weights and biochemical analysis for sexes and doses of mice between control and experimental groups. As a result all of the groups were alive during experimental periods and none of the significant clinical symptom and body weight changes were shown in all of the groups. Plasma glucose levels were valued for both control and experimental groups and there were no significant differences between the groups. The activities of aminotransferase were not increased in all experimental groups compared to control groups. The results suggest that the toxicity of the aleurone layer of Oryza sativa cvs. Jukjinjubyeo, Heugjinjubyeo and Heughyangbyeo are low and its $LD_{50}$ is over 10.0 g/kg body weight in both male and female mice.

• Korean journal of applied entomology
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• v.56 no.4
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• pp.395-402
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• 2017

Overuse of synthetic pesticides caused negative side-effects such as environmental contamination, development of insect pests' resistance, and effects on non-target organisms. Plant origin substances without/or with low mammalian toxicity have been considered as promising alternatives to the synthetic pesticides. Fumigant toxicity of the essential oil of Iranian Yarrow, Achillea millefolium L., was investigated against a cosmopolitan stored-product insect pest: saw-toothed grain beetle (Oryzaephilus surinamensis L.). Chemical profile of this essential oil was studied by Gas Chromatography-Mass Spectrometry. Tested concentrations were significantly effective to the mortality of insect pest. A positive correlation between essential oil concentrations and pest mortality were realized. LC50 value (lethal concentration needed to 50% mortality) was achieved as $17.977(16.195{\pm}20.433){\mu}l/l$ air. The main components were 1,8-Cineole (13.17%), nerolidol (12.87%), ${\alpha}$-cubebene (12.35%), artemisia ketone (6.69%), ${\alpha}$-terpineol (5.27%), alloaromadendrene oxide (4.71%) and borneol (3.99%). Terpenic compounds including monoterpene hydrocarbons (8.19%), monoterpenoids (44.23%), sesquiterpene hydrocarbons (21.69%) and sesquiterpenoids (22.24%) were 96.35% of the total identified compounds. Results indicated that the terpene-rich A. millefolium essential oil may be considered as a safe bio-agent in the O. surinamensis management.

• Korean Journal of Environmental Agriculture
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• v.7 no.1
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• pp.58-64
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• 1988

The acute oral, intraperitoneal and subacute toxicity of monocrotophos, an insecticide, was studied in albino rats. The acute oral $LD_{50}$ values for female and male rats were 5.0mg/kg and 8.7mg/kg, respectively. Conversely the intraperitoneal $LD_{50}$ values for female and male rats were 4.9mg/kg and 6.0mg/kg, respectively. Plasma cholinesterase (ChE) activity in rats treated with a single dose was the most depressed 4 hours after administration, but returned to normal within 72 hours of administration. Significant depression of body weight gain and food consumption was observed in rats receiving the 3.5mg/kg/day dose level for 28 days as compared with the controls. Additionally plasma ChE activity depression was also observed.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.114-117
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• 2007

The effects of faecally excreted ivermectin on the survival and growth of the common Korea earthworm Eisenia fetida (Savigny), have been studied in the laboratory. Cow dung was collected 1, 2, 3 and 7 days after ivermectin subcutaneous injection. The mortality of the worms provided with untreated dung was 0% whereas mortality within a week was high as 73.7%, 98.3% in dung which were excreted 1 and 2 days from dosing, respectively. The growth rate of the worms fed dung from 1 day excreted dung from cattle given ivermectin was 75% lower than that recorded on the control. In total number of hatchling earthworm in each treatment, 1 day after treatment produced the lowest compared with untreated control. However, dung from cattle treated with ivermectin did not prevented the rate of hatchling from each cocoon of earthworm. The results show that ivermectin is less toxic to $2^{nd}$ generation of earthworm. We concluded that ivermectin have adverse effects on the survival and growth of E. fetida when exposed through dung under laboratory conditions. This results will be discussed in relation to the effects of anthelmintics on non-target organism in our ecosystem.

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.126-136
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• 1998

For the purpose of effective control strategy of the melon aphid, Aphis gossypii and the diamondback moth, Plutella xylostella, thiamethoxam and 3 other insecticides in different classes were used with bioassay test methods in laboratory and greenhouse. They were examined to evaluated and compared with contact toxicity, stomach toxicity, rapid action, systemic action, and residual effect of imidacloprid, thiamethoxam (nicotinoids), acephate (organophosphorates), and carbosulfan (carbamates). As results of contact toxicity responses of A. gassypii against 4 insecticides using a spray application method, $LC_{50}$ values of acephate, carbosulfan, imidacloprid and thiamethoxam were 41.9, 5.2, 1.1, and 0.7 ppm. respectively. In the evaluation of stomach toxicity response of P. xylostella using a leaf-dipping method, with the 2nd instar larva $LC_{50}$ values of imidacloprid, thiamethoxam and acetamiprid were 64.9, 24.6 and 15.2 ppm, with the 3rd instar larva were 125.2, 42.7 and 27.8 ppm. and with the 4th instar larva were 241.1, 44.5 and 23.9 ppm, respectively. In the case of rapid action to A. gossypii using a spray application method after inoculation, $LT_{50}$ values of imidacloprid, thiamethoxam, carbosulfan, and acephate were 26.6, 28.0, 30.3, and 41.7 min. respectively. Otherwise, in the inoculation after applying compounds, $LT_{50}$ values of thiamethoxam, imidacloprid, and carbosulfan were 95.5, 118.0, and 122.9 min. respectively. Evaluating to systemic action from the abaxial surface to the adaxial surface of red pepper leaf with spray method, $LT_{50}$ values of thiamethoxam, imidacloprid, and carbosulfan were 162.2, 168.9, and 564.1 min. respectively. For the systemic action from the lower leaves to the upper leaves on red pepper, $LT_{50}$ values of carbosulfan, thiamethoxam, imidacloprid, and acephate were 2.3, 2.9, 3.0, and 8.8 days, respectively. In red pepper plant, $LT_{50}$ values of carbosulfan, imidacloprid, thiamethoxam, and acephate on the systemic action from the roots to the upper leaf were 0.6, 1.0, 1.0, and 13.8 days, respectively. As these results, it might be that thiamethoxam was excellent on systemic effect in red pepper. For the evaluation of residual effect on red pepper with A. gossypii, thiamethoxam and imidacloprid maintained high control effects as over 80% upto 10 days after treating compounds.

• Korean Journal of Environment and Ecology
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• v.20 no.3
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• pp.345-351
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• 2006

This study investigates the toxic effects of $Cd^{2+}$on frog (Rana dybowskii) by the determination of oocyte maturation and development of embryo exposure to different concentrations of the toxicant. The results show that $Cd^{2+}$ concentration of 0.1ppm suppressed the maturation of the oocytes. To examine the reversibility of the inhibitory effects, the oocytes were exposed to the $Cd^{2+}$ only for 3 hours, and then transferred to plain medium and cultured further for 17 hours. The oocytes were recovered from the toxic effect of the $Cd^{2+}$ when they were exposed to 1ppm, but not to 2.5ppm of the $Cd^{2+}$. The development of 2 cell embryos to 32 cell was completely suppressed at 0.1ppm and the longer the embryos were exposed to the $Cd^{2+}$, the more damage appeared to the embryos and the cytolysis of the 32 cell was induced by $Cd^{2+}$ at 0.1ppm. On the other hand, the embryos of blastula stage were cultured 96 hours in presence of the $Cd^{2+}$ at various concentrations and were examined. The rates of mortality and malformed larvae were investigated by probit analysis. From the results of LC$_{50}$ of 0.1ppm and EC$_{50}$ of 0.08ppm, Tl of 5.0 was derived, which indicates $Cd^{2+}$ is to be considered a teratogenic compound. Such specific malformations occurred in 14.3% as spine deformations at the 0.05ppm, in 75.0% as tail deformations at the 0.1ppm, in 66.7% as abdominal deformations at the 0.01ppm and in 26.0% as profound deformations at the 0.1ppm of $Cd^{2+}$ concentration which living embryos were exposed to. $Cd^{2+}$ suppressed growth to head-tail length at 0.1ppm. In conclusion, The study results reveal that $Cd^{2+}$ must be considered highly toxic effect to oocyte maturation and embryonic development.

• Journal of Life Science
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• v.24 no.2
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• pp.191-195
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• 2014

Essential oils extracted or purified from various plants have shown various beneficial effects. Seed parts of Schizandra chinensis Baillon (Schisandrae Semen) have been used as a traditional medicine for thousands of years in parts of Asia, including Korea, China, and Japan. However, the pharmacological mechanisms of essential oils purified from S. fructus (S. chinensis Baillon) remain largely unresolved. The aim of this study was to investigate the safety of Schisandrae Semen essential oil (SSeo) by a single- dose toxicity study in mice. SSeo was orally administered at a dose of 5,000 mg/kg in ICR mice. All animals were sacrificed after 14 days of treatment. After a single administration, mortality, clinical signs, body weight changes, and gross pathological findings were observed for 14 days. We also measured parameters of organ weight, clinical chemistry, and hematology. No toxicological change related to the test substance or mortality was observed after administration of a single oral dose of SSeo. There were no adverse effects on clinical signs, body weight, or organ weight and no gross pathological findings in any treatment group. The clinical chemistry and hematological parameters were within the normal ranges except total bilirubin. Therefore, the approximate lethal dose for oral administration of SSeo in mice was considered to be over 5,000 mg/kg. The results on the single-dose toxicity of SSeo indicate that it is not possible to reach oral dose levels related to death or dose levels with any harmful side effects.

• The Korean Journal of Pesticide Science
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• v.17 no.4
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• pp.363-370
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• 2013

Susceptibility of each developmental stage of Phthorimaea operculella (Lepidoptera: Gelechiidae) were investigated using 16 insecticides which are available in the market in Korea. For the eggs and pupae, only spinosad showed a 71.1% inhibition rate for egg hatchability and a 66.7% inhibition rate for emergence. For the 3rd instar larvae, the feeding toxicities were over 90% for fenitrothion ($LC_{50}$ 336.6 ppm), esfenvalerate ($LC_{50}$ 8.6 ppm), ethofenprox ($LC_{50}$ 35.7 ppm), and emamectin benzoate ($LC_{50}$ 0.05 ppm). Furthermore, the contact toxicities were over 90% for esfenvalerate ($LC_{50}$ 0.87 ppm), ethofenprox ($LC_{50}$ 16.5 ppm), emamectin benzoate ($LC_{50}$ 0.53 ppm), and spinosad ($LC_{50}$ 2.48 ppm) at the recommended concentrations. Deltamethrin and spinosad yielded 100% mortality for adult P. operculella 48 h after treatment. The adult female fecundity was inhibited by deltamethrin, esfenvalerate, emamectin benzoate, spinosad and dinotefuran, which were significantly different from the control. The adult longevities (7.3-8.3 days) were reduced by approximately 1-2 days compared with the control (9.3 day). The emamectin benzoate maintained 100% insecticidal activity 14 days after treatment and ethofenprox maintained over 90% activity 7 days after treatment.