• 식물병연구
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• 제24권4호
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• pp.313-320
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• 2018

벼 붉은곰팡이병에 대한 품종별 반응과 기상조건에 따른 감염영향을 알아보기 위하여 장려품종 재배포장의 기상자료와 수확한 벼의 이병립율과 Fusarium 균을 동정하였다. 출수개화 전인 7월 하순부터 등숙기인 9월말까지의 평균기온이 수확후 산물벼의 이병립율에 크게 영향을 주었으며, 평균기온이 비슷한 2010년과 2013년에는 같은 기간의 누적강우량, 누적 강우일수, 2일 이상 강우지속횟수와 관련이 있었다. 2010년과 2013년에 수확한 벼에서 Fusarium 균의 종복합체별 분리비율은 FGSC에 대해 각각 57%과 45%, FIESC에 대해 35%과 50%, FFSC에 대해 8%과 5%이었다. FGSC와 FFSC의 분포비율은 2010년이 2013년에 비해 높았다. Fusarium 균의 자연감염에 대한 품종반응은 26개 장려품종 중 미향 품종만이 FGSC 자연감염에 대한 저항성을 보였으며, 남평, 하이아미, 영호진미 품종은 총 Fusarium 병원균의 자연감염에 대하여 전반적인 저항성을 보였다. 그 밖의 대부분의 장려품종은 저항성 또는 감수성으로 구분할 수 없었다. 본 연구결과는 Fusarium 균 자연감염에 대한 저항성과 감수성을 판단하는 기초자료로서 의의가 있다.

• 농약과학회지
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• 제3권2호
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• pp.19-28
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• 1999

외부 형태가 다른 피속류 46종을 대상으로 피 방제용 경엽처리 제초제인 cyhalofop-butyl과 pyribenzoxim의 약제반응을 보고, 그 결과 약제반응이 상이한 피속류를 선발하여 $^{14}C$ 화합물을 이용, 흡수이행 및 체내대사 등을 시험하였다. Cyhalofop-butyl에 감수성인 황간 돌피, 내성인 제주 강피 그리고 pyribenzoxim에 감수성인 남양주 물피, 내성인 아산 물피를 선발하였다. $^{14}C$-Cyhalofop-butyl과 $^{14}C$-pyribenzoxim의 피 체내에서의 흡수이행 특성은 내성 피보다는 감수성 피에서 더 빨리 이행되는 경향을 보였으며, 뿌리보다는 지상부의 다른 부위로 이행되는 경향이었다. 감수성 정도가 다른 피속류에 $^{14}C$ 화합물을 처리한 결과, cyhalofop-butyl에서는 2종, pyribenzoxim에서는 1종의 미확인 대사산물이 검출되었으며, 대사산물의 분포비율을 보면 불활성 물질로 추정되는 대사산물의 양은 감수성 피보다 내성 피에서 높았다. $^{14}C$ 화합물을 처리한 피속류에서 결합 잔류물 형태로 잔류한 양은 감수성 피보다 내성 피에서 더 많이 잔류하였다.

• BMB Reports
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• 제53권2호
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• pp.88-93
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• 2020

Cisplatin is a widely used anti-cancer agent. However, the effectiveness of cisplatin has been limited by the commonly developed drug resistance. This study aimed to investigate the potential effects of endoplasmic reticulum (ER) stress to overcome drug resistance using the cisplatin-resistant A2780/CisR ovarian cancer cell model. The synthetic chalcone derivative (E)-3-(3,5-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (named DPP23) is an ER stress inducer. We found that DPP23 triggered apoptosis in both parental cisplatin-sensitive A2780 and cisplatin-resistant A2780/CisR ovarian cancer cells due to activation of reactive oxygen species (ROS)-mediated unfolded protein response (UPR) pathway in the endoplasmic reticulum. This result suggests that ROS-mediated UPR activation is potential in overcoming drug resistance. DPP23 can be used as a target pharmacophore for the development of novel chemotherapeutic agents capable of overcoming drug resistance in cancer cells, particularly ovarian cancer cells.

• 생태와환경
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• 제45권4호
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• pp.420-443
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• 2012

An Individual-Based Model (IBM) was developed by employing natural and toxic survival rates of individuals to elucidate the community responses of benthic macroin-vertebrates to anthropogenic disturbance in the streams. Experimental models (dose-response and relative sensitivity) and mathematical models (power law and negative exponential distribution) were applied to determinate the individual survival rates due to acute toxicity in stressful conditions. A power law was additionally used to present the natural survival rate. Life events, covering movement, exposure to contaminants, death and reproduction, were simulated in the IBM at the individual level in small (1 m) and short (1 week) scales to produce species abundance distributions (SADs) at the community level in large (5 km) and long (1~2 years) scales. Consequently, the SADs, such as geometric series, log-series, and log-normal distribution, were accordingly observed at severely (Biological Monitoring Working Party (BMWP<10), intermediately (BMWP<40) and weakly (BMWP${\geq}50$) polluted sites. The results from a power law and negative exponential distribution were suitably fitted to the field data across the different levels of pollution, according to the Kolmogorov-Smirnov test. The IBMs incorporating natural and toxic survival rates in individuals were useful for presenting community responses to disturbances and could be utilized as an integrative tool to elucidate community establishment processes in benthic macroin-vertebrates in the streams.

• Fisheries and Aquatic Sciences
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• 제11권2호
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• pp.113-123
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• 2008

We modeled fish school movements as a capture process in relation to the purse seine method using the three steps of the stimulus-response process (i.e., input stimuli, central decision-making and output reaction). Input stimuli of the model were categorized as either physical stimuli such as visual stimulus, sound stimulus, water flow, and weather or as biological stimuli such as species and size, swimming performance, sensual sensitivity, and presence of prey or predators. The output process determining the spatial orientation of the fish school for 3-D movements was based on swimming speed and angular change in the fish response, and these movements were animated as the relative geometry between the fish school and the purse seine. Simulations were carried out for skipjack tuna (Katsuwonus pelamis) schools reacting to a pelagic purse seine in the southwest Pacific Ocean. Simulation results showed that escape ratios varied from 20 to 70% by the relevant ranges in the stimulus-response thresholds, swimming speeds, and angular changes of fish schools were similar to those observed in the field. Therefore, with knowledge of relevant parameters, this model can be used to predict capture and escape probabilities of purse seine operations for different fish species or conditions.

• Journal of Forest and Environmental Science
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• 제37권2호
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• pp.104-115
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• 2021

The research attempted to analyze the medicinal plant species richness in the vertical gradient from lower to the highest elevation of Makawanpur, focusing on the relationship between species richness and elevation which is very important for conservation and management of species diversity. Inventory was carried out in the study area by taking sampling intensity of 0.5% in the effective area. Altogether, 42 sample plots were laid in the field with the help of GIS software maintaining 50 m altitude difference. High species diversity was found in the herbs species whereas shrubs have comparatively low species diversity. The maximum species richness is found in herbs and poles whereas shrubs and trees have relatively low species richness. Research showed that species richness of medicinal plants increased with altitudinal gradient. While analyzing the species richness from 350 to 2,550 m (msl), the highest species richness was received with the elevation ranges from 1,800 m to 2,300 m. There was a positive relationship between species richness and altitudinal gradient in the study area. In addition, we have recorded the high value medicinal plants after 1,800 m altitude and rarely within 1,000 m. Medicinal plants correlated both positive and negative relationships with the increased altitude. The altitudinal response has positively seen except density (n/ha) of Shrubs. Domestication and cultivation of high value medicinal plants should be promoted in community forest including private lands. Training, workshops and awareness programs should be conducted to make people aware about medicinal plants resource utilization, conservation and commercialization of available medicinal plants.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2002년도 춘계 공동학술발표회
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• pp.466-468
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• 2002

• The Plant Pathology Journal
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• 제21권2호
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• pp.99-101
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• 2005

Host cell death occurs during many, but not all, interactions between plants and the pathogens that infect them. This cell death can be associated with disease resistance or susceptibility, depending on the nature of the pathogen. The most well-known cell death response in plants is the hypersensitive response (HR) associated with a resistance response. HR is commonly regulated by direct or indirect interactions between avirulence proteins from pathogen and resistance proteins from plant and it can be the result of multiple signaling pathways. Ion fluxes and the generation of reactive oxygen species commonly precede cell death, but a direct involvement of the latter seems to vary with the plant-pathogen combination. Exciting advances have been made in the identification of cellular protective components and cell death suppressors that might operate in HR. In this review, recent progress in the mechanisms by which plant programmed cell death (PCD) occurs during disease resistance will be discussed.

• Molecules and Cells
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• 제19권2호
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• pp.167-179
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• 2005

The cells of metazoans respond to DNA damage by either arresting their cell cycle in order to repair the DNA, or by undergoing apoptosis. This response is highly conserved across species, and many of the genes involved in this DNA damage response have been shown to be inactivated in human cancers. This suggests the importance of DNA damage response with regard to the prevention of cancer. The DNA damage checkpoint responses vary greatly depending on the developmental context, cell type, gene expression profile, and the degree and nature of the DNA lesions. More valuable information can be obtained from studies utilizing whole organisms in which the molecular basis of development has been well established, such as Drosophila. Since the discovery of the Drosophila p53 orthologue, various aspects of DNA damage responses have been studied in Drosophila. In this review, I will summarize the current knowledge on the DNA damage checkpoint response in Drosophila. With the ease of genetic, cellular, and cytological approaches, Drosophila will become an increasingly valuable model organism for the study of mechanisms inherent to cancer formation associated with defects in the DNA damage pathway.

• Journal of Microbiology
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• 제44권1호
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• pp.1-10
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• 2006

Adaptation to any undesirable change in the environment dictates the survivability of many microorganisms, with such changes generating a quick and suitable response, which guides the physiology of bacteria. During nutritional deprivation, bacteria show a stringent response, as characterized by the accumulation of (p)ppGpp, resulting in the repression of stable RNA species, such as rRNA and tRNA, with a concomitant change in colony morphology. However, genes involved in amino acid biosynthesis become over-expressed to help bacteria survive under such conditions. The survivability of pathogenic bacteria inside a host cell also depends upon the stringent response demonstrated. Therefore, an understanding of the physiology of stringent conditions becomes very interesting in regulation of the growth and persistence of such invading pathogens.