• 한국응용곤충학회지
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• 제40권3호
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• pp.259-264
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• 2001

해충의 생물적 방제 인자로서 주목받고 있는 곤충병원선충(Steinernema carpocapsae)과 이들의 공생세균(Xenorhabdus nematophilus)이 유용곤충인 누에(Bombyx mori)와 그물등개미(Pristomyrmex pungens)에 상이한 독성을 보였다. S. carpocapsae는 누에에 대해 매우 높은 살충력(반수치사농도: 4IJs (감염태 유충수)/ml)을 보이는 반면, 그물등개미에 대해서는 매우 약했다. (반수치사농도: >150,000 IJs/ml). 반면에 X. nematophilus는 그물등개미에 대해 높은 경구독성(반수치사농도: $1.4$\times$10^3$cfu (콜로니 형성수)/ml)을 보였으나, 누에에 대해서는 낮았다. (반수치사농도: >$10^{8}$ cfu/ml). 또한 실험동물 랫드(Rattus norvegicus)에 S. carpocapsae와 X. nematophilus를 강제로 경구투여 한 결과 시험 전기간(21일)동안 치사개체는 없었으며, 내부 장기에서 처리한 공생세균과 선충은 발견되지 않았다.

• 대한수의학회지
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• 제15권1호
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• pp.47-50
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• 1975

Experimental studies were performed to observe the effect of exposure to 100% oxygen in 2 atmospheres on the lung tissue of rats, and to examine the resistant effect of DL-${\alpha}$-tocopherol. The following results were made through this experiment: 1. Half-lethal time by oxygen poisoning was longer in tocopherol treated group than not treated group. 2. Ratio of lung weight to body weight was significantly higher in fatal group within half-lethal time than survival group (p<0.01). 3. Histopathological changes of the lung by oxygen toxicity were vascular congestion, pulmonary edema, hemorrhage and emphysematous change. The degree of changes were rather marked in experimental group than tocopherol untreated group. Those were regard as the changes being occurred during tolerance process by prolonging half-lethal time.

• 한국환경과학회지
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• 제4권5호
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• pp.157-157
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• 1995

In order to analyze the sex-linked lethal mutagenic effects of ethyl methanesulfonate (EMS) in Drosophila melanogaster, the mutagenicities from the attached-X and Basc method have been detected. The indexes of relative lethal mutations at 2.0 and 4.0mM EMS treated group using the attached-X method were about 1.5 and 2.4 times than that of 1.0mM treated group, respectively. EMS had more pronounced effect in the sperm and spermatid stages in the induction of X-linked lethal mutations during the spermatogenesis. And, in the induction of X-linked recessive lethal mutations from the Basc method, the mutation frequency of 4.0mM EMS treated group as compared with 2.0mM was more than three fold. Two assay systems used in this study can support mutually according to experimental purposes, and the area of its application can be considerably wide.

• 한국환경과학회지
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• 제4권5호
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• pp.543-549
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• 1995

In order to analyze the sex-linked lethal mutagenic effects of ethyl methanesulfonate (EMS) in Drosophila melanogaster, the mutagenicities from the attached-X and Basc method have been detected. The indexes of relative lethal mutations at 2.0 and 4.0mM EMS treated group using the attached-X method were about 1.5 and 2.4 times than that of 1.0mM treated group, respectively. EMS had more pronounced effect in the sperm and spermatid stages in the induction of X-linked lethal mutations during the spermatogenesis. And, in the induction of X-linked recessive lethal mutations from the Basc method, the mutation frequency of 4.0mM EMS treated group as compared with 2.0mM was more than three fold. Two assay systems used in this study can support mutually according to experimental purposes, and the area of its application can be considerably wide.

• 전기의세계
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• 제29권1호
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• pp.21-27
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• 1980

The effect of electric shock on human body is enormousness, which leads to warmth, tingling, and even death. The mean values of perception currents obtained on 91 men and 39 women are about 0.77(mA) for men and 0.57(mA) for women. The mean value for women is approximately seven tenths that of men. An individual can tolerate, with no adverse effects, repeated exposure to the reactions associated with currents of his let-go level, and the mean value of let-go currents obtained from 27 normal men is 6.29(mA). Lethal currents flowing human body is very dangerous even for a short time. So, it is necessary to have recourse to animal experiments ot determine lethal current for human. An analysis of experimental data indicates that body weight and shock duration are important factors in determining the lethal current. It is suggested that the relationship between current and shock duration is given by I=K/.root.T, and lethal current is proportional to body weight, where I is the current in milliampere, and T is the time in seconds.

• Journal of Ginseng Research
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• 제37권1호
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• pp.80-86
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• 2013

Korean red ginseng has been shown to possess a variety of biological activities. However, little is known about antiviral activity of ginsenosides of Korean red ginseng. Here, we investigated the protective effect by oral administration of various ginsenosides on the lethal infection of haemagglutinating virus of Japan (HVJ) in mice. In a lethal infection model in which almost all mice infected with HVJ died within 15 days, the mice were administered orally (per os) with 1 mg/mouse of dammarane-type (ginsenoside-Rb1, -Rb2, -Rd, -Re, and -Rg2) or oleanolic acid-type (ginsenoside-Ro) ginsenosides 3, 2, and 1 d before virus infection. Ginsenoside-Rb2 showed the highest protective activity, although other dammarane-type and oleanolic acid-type ginsenosides also induced a significant protection against HVJ. However, neither the consecutive administration with a lower dosage (300 ${\mu}g$/mouse) nor the single administration of ginsenoside-Rb2 (1 mg/mouse) was active. In comparison of the protective activity between ginsenoside-Rb2 and its two hydrolytic products [20(S)- and 20(R)-ginsenoside-Rg3], 20(S)-ginsenoside-Rg3, but not 20(R)-ginsenoside-Rg3, elicited a partial protection against HVJ. The protective effect of ginsenoside-Rb2 and 20(S)-ginsenoside-Rg3 on HVJ infection was confirmed by the reduction of virus titers in the lungs of HVJ-infected mice. These results suggest that ginsenoside-Rb2 is the most effective among ginsenosides from red ginseng to prevent the lethal infection of HVJ, so that this ginsenoside is a promising candidate as a mucosal immunoadjuvant to enhance antiviral activity.

• BMB Reports
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• 제44권12호
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• pp.811-815
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• 2011

Inhalational anthrax is caused by B. anthracis, a virulent sporeforming bacterium which secretes anthrax toxins consisting of protective antigen (PA), lethal factor (LF) and edema factor (EF). LF is a Zn-dependent metalloprotease and is the main determinant in the pathogenesis of anthrax. Here we report the identification of a lead small-molecule inhibitor of anthrax lethal factor by screening an available synthetic small-molecule inhibitor library using fluorescence-based high-throughput screening (HTS) approach. Seven small molecules were found to have inhibitory effect against LF activity, among which SM157 had the highest inhibitory activity. All theses small molecule inhibitors inhibited LF in a noncompetitive inhibition mode. SM157 and SM167 are from the same family, both having an identical group complex, which is predicted to insert into S1' pocket of LF. More potent small-molecule inhibitors could be developed by modifying SM157 based on this identical group complex.

• 한국토양동물학회지
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• 제1권2호
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• pp.81-88
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• 1996

Entomopathogenic nematodes, Steinernema carpocapsae, was able to invade and kill the several lepidopteran pests including the beet armyworm, Spodeptera exigua Hubner, which was the most effective target host. The beet armyworms treated with the effective nematode concentrations were died within 48 hrs. The lethal effect of the nematode was varied among the developmental stages of the host. The fifth instar larvae of the beet armyworm was more vulnerable to the nematode than the third instar larvae. Pupae was, however, refractory to the nematode. All three bioessays (topical application, filter paper test, and soil treatment) showed the positive correlation between the number of the treated nematodes and the mortality of the host. Topical application was the most effective and fast-acting method so that it gave the lethal effect 2 days earlier than did filter paper test at the same number of the treated nematodes. Soil treatment required higher number of the nematodes to get the effective lethality than did filter paper test. The fifth instar larvae of the beet armyworm expressed the specific hemolymph proteins of 5 to 10 kDa in response to nematode infection.

• 생명과학회지
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• 제9권1호
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• pp.106-110
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• 1999

감염성 Vibrio vulnificus에 의한 패혈증과 같은 질병의 원인을 알아보기 위하여 Vibrio vulnificus로 부터 세포벽 lipopolysaccharide를 추출한 후 지방산 조성을 분석하고 limulus gelation activity와 lethal toxicity를 측정하였다. 이 결과들을 비감염성 Escherichia coli LPS와 감염성 Salmonella typhimurium LPS의 것들과 비교하였다. V. vulnificus LPS의 주 지방산은 myristic acid 이었고 E. coli LPS는 lauric acid, S. typhimurium LPS는 capric acid 이었다. 세가지 LPS의 Limulus gelation activity는 같았으며(0.1ng/ml), V. vulnificus LPS의 lethal toxicity는 E. coli LPS와 S. typhimurium LPS의 것과 비슷하였다. LPS 이외에도 exotoxin과 같은 인자들도 V. vulnificus에 의한 세포 독성의 원인으로 고려해야 할 것이다

• Advances in Traditional Medicine
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• 제8권2호
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• pp.192-195
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• 2008

The effect of aqueous and alcoholic extract of roots of Berberis aristata was studied on the spontaneous movements of the whole worm (w.w) preparation and nerve muscle (n.m) complex of cattle filarial parasite Setaria cervi and on the survival of microfilariae. Only aqueous extract could inhibit the spontaneous movements of S. cervi, characterized by initial stimulation followed by reversible paralysis. The concentration required to produce similar effect on n.m complex was less as compared to the w.w. The lethal concentration 50 and lethal concentration 90 for aqueous extract were 48 ng/ml and 65 ng/ml.