검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 37

        21.
        2017.10 구독 인증기관·개인회원 무료
        RNA interference (RNAi) has been considered as an alternative strategy to control agricultural pests whereby double-strandedRNA triggers a potent and specific inhibition of its homologous mRNA. Since small double-stranded RNAs are requiredfor various RNAi applications, there is a need for cost-effective methods for producing large quantities of high-qualitydsRNA. Bacillus thuringiensis produces much insecticidal proteins with expression of their encoding genes being drivenby sporulation-dependent promoters. To develop dsRNA mass-production platform utilizing Bt, the pHT1K-EGFP plasmidvector which has cyt1Aa sporulation-dependent promoter was constructed. The transcriptional level of target gene (EGFP)is higher 113 times than Bt reference gene (ssPE). It was applied to protect honeybee from Sacbrood virus, so targetgene was replaced to SBV-vp1. By ingestion of Bt-derived dsRNA to honeybee shows positive effect on SBV suppression.
        22.
        2017.04 구독 인증기관·개인회원 무료
        Secondary metabolites isolated from Actinomycete have been studied to find potent pest control agents as their insecticidal and growth inhibitory activities. In order to investigate novel insecticidal compounds, second metabolites from 363 Actinomycete isolates were evaluated for their insect growth regulatory activities. Among them, ethyl acetate extracts from ten Streptomyces spp. showed high level of Juvenile hormone antagonist activity. In addition, their insecticidal activities were tested against larvae of Aedes albopictus, Plutella xylostella and Laodelphax striatellus. These results suggested that secondary metabolites from Streptomyces spp. could be used for development of novel IGR-based insecticides.
        23.
        2017.04 구독 인증기관·개인회원 무료
        Plant essential oils have been reported to show repellent, insecticidal and growth-reducing effect on many insect herbivores. Recently, it has been reported that plants synthesize secondary metabolites regulating insect juvenile hormone (JH) receptor complex as a part of their defense mechanisms. We tested 180 plant essential oil compounds using a yeast two-hybrid system transformed with the Aedes aegypti JH receptor as a reporter system. Among them, we identified 17 compounds that showing high JH agonist (JHA) or antagonist (JHAN) activities. They were grouped into 4 groups by their structural similarity and their insecticidal activity was tested against larvae of Aedes albopictus, Plutella xylostella, Plodia interpunctella and Laodelphax striatellus. These results could provide insights on the plant-insect coevolution and may be useful for the development of insect specific and safe pesticides.
        24.
        2017.04 구독 인증기관·개인회원 무료
        RNA interference (RNAi) is an universal gene-knockdown mechanism in eukaryotic organisms including insects. RNAi has been considered as an alternative strategy to control agricultural pests whereby double-stranded RNA triggers a potent and specific inhibition of its homologous mRNA. Bacillus thuringiensis (Bt) is a spore-forming bacterium that produces a copious amount of crystal proteins δ-endotoxins under the control of sporulation-dependent promoter. In order to develop dsRNA mass-production platform utilizing recombinant Bt, the pHT1K-EGFP which expresses dsRNA against EGFP under the control of Cyt1-Aa sporulation-dependent promoter was constructed and the expression level of transgene (EGFP) was confirmed by qPCR analysis. These results suggested that Bt’s potential of becoming a new platform in dsRNA production.
        25.
        2017.04 구독 인증기관·개인회원 무료
        Insect growth regulators (IGRs) are insecticides that disrupt the normal development of target insects by inducing symptoms such as premature molting or supernumerary larval stages. Juvenile hormone (JH)-based IGRs are of particular interest because they simulate or interfere with the formation of juvenile hormone receptor complex. Insect larvae generally have been poorly susceptible to JH agonists (JHAs) because endogenous JH titer is already high in the larval stage. In contrast, JH antagonists (JHANs) might be more effective for control of target pests in larval stages through interference in the status quo action of JHs. In this study, we tested 2,354 chemical compounds using the yeast-two hybrid system to identify JHANs. Among them, K265674 sample was selected and its insecticidal activity was evaluated against Aedes albopictus larvae. These results may be useful for development of novel IGR insecticide.
        26.
        2017.04 구독 인증기관·개인회원 무료
        Entomopathogenic fungi have been widely studied for their potential as the effective biological control agents. They produce variety of secondary metabolites with insecticidal activities, and it is reasonable to assume that entomopathogenic fungi might produce secondary metabolites modulating juvenile hormone for their survival against defense mechanisms of host insect. In this study, acetone extract of the Lecanicillium spp. cultured on unpolished rice medium showed juvenile hormone antagonist (JHAN) activity in the yeast-two hybrid β-galactosidase assay and high insecticidal activity against Aedes albopictus and Plutella xylostella. In addition, to compare bioactivities of secondary metabolites from solid and liquid culture, the Lecaniciilium spp. strain cultured on unpolished rice medium or PDB medium were serially extracted with acetone and ethyl acetate respectively. Both extracts showed JHAN activity and high insecticidal activity against A.albopictus. Theses results suggested that secondary metabolites of entomopathogenic fungi could be useful for development of novel IGR insecticides.
        27.
        2017.04 구독 인증기관·개인회원 무료
        Rice stripe virus (RSV) is one of the serious plant pathogenic viruses for rice transmitted by small brown planthopper (SBPH), Laodalphax striatellus. RNA interference (RNAi) was recently suggested as a promising strategy for controlling insect pests, including those that serve as important vectors for plant pathogens. To disturb transmission of the RSV in SBPH using RNAi pathway, we chose nine genes highly expressed in RSV-viruliferous SBPH by transcriptome sequencing. These SBPH-derived dsRNAs were applied to the insects indirectly through xylem of rice leaves by irrigation. qPCR result demonstrated that five out of nine SBPH-derived dsRNAs successfully reduced the replication of RSV in viruliferous SBPH in dose-dependent manner, suggesting that these five dsRNAs could suppress replication of RSV and provide a new tool for RSV control strategy.
        30.
        2012.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Socket sclerosis can be an obstacle for orthodontic space closure, however, the precise histomorphogenetic mechanism has not been elucidated up to date. A 73 years old female complained of dull pain on palpation in the extraction site of the left maxillary first molar, and uncomfortable to use her complete denture. In panoramic X-ray view the socket sclerosis was clearly demarcated as a radiopaque outline of extracted root. In histological examination the socket sclerosis showed the basophilic deposition of cementum- like materials in the peripheral rim of trabecular bones instead of eosinophilic osteoid materials for intramembranous ossification. In the immunohistochemical staining for osteogenetic proteins, BMP-2 was strongly positive in the peripheral rim of trabecular bone, in which RANKL and osteoprotegerin were also consistently positive. Particularly, versican, a marker of cementum was also positive in the peripheral rim of the trabecular bone. Therefore, it is presumed that the trabecular bones of socket sclerosis were hypermineralized by cementoid ossification, producing cementum-like materials by osteoblasts/cementoblasts derived from the previous periodontium.
        4,000원
        31.
        2011.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the status of domestic and foreign power blogs that serve as professional source of information and to clarify the difference of the criteria for the certification and selection of power blogs. The study also analyzed the configuration of contents and the characteristic of categories of the power blogs. Eleven domestic blogs were examined, of which ten were certified as power blogs on several portal sites and one blog was operating in English. Furthermore twelve foreign blogs were examined, of which ten blogs were selected from the graded list of www.alexa.com for the Fashion Power Blog TOP 20 adopted on www.telegraph.co.uk in 2009, and two noticeable blogs were selected additionally. Data were analyzed by both theoretical and exploratory studies. The exploratory study was conducted by fourteen majors, who took interest in the blogs and were divided into two groups to look at the domestic and foreign sites, from 12 October to 12 November in 2010. The types of blogs were classified by frequency analysis of interactivity, interest provision, information provision and purchase capability. The investigators checked the type of the contents of each blog and the frequencies were used for the classification type. The analysis showed that the frequencies were in the order of information provision, followed by interest provision, and purchase capability for foreign blogs, while interest provision was followed by information provision for domestic blogs. Interactivity, interest provision, information provision and purchase capability were generally reflected in foreign blogs. Rather than interest provision and information provision, however, interactivity and purchase capability were reflected relatively weakly in domestic blogs.
        5,200원
        32.
        2017.07 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Hovenia dulcis fruit powder (HFP) has shown diverse functional activities; thus, it is rational to incorporate HFP into suitable food products with enhanced nutritional and functional quality, and their incorporation into bakery products such as cookies could be a good alternative for the increase of consumption. The aim of this study was to examine the effect of HFP addition on the quality characteristics of cookies. The pH of cookie doughs ranged from 5.80-6.34, with no remarkable differences by HFP addition. Density of cookie doughs significantly decreased upon addition of HFP (p<0.05), but there were no significant differences among samples added with HFP (p>0.05). Moisture content and spread factor of cookies significantly increased with higher content of HFP in the formulation (p<0.05). For color values of cookie surface, L* and b*-values decreased while a*-value increased as a result of HFP substitution (p<0.05). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azino-bis-3-ethylbenzthiazoline-6- sulphonic acid (ABTS) radical scavenging activities were significantly increased (p<0.05) with higher substitution of HFP, showing a positive correlation. Hedonic sensory results indicated that cookies supplemented with 4% HFP received the most favorable acceptance scores for sensory attributes. Overall, HFP-added cookies could be developed with improved physicochemical qualities without sacrificing consumer acceptability.
        33.
        2016.10 서비스 종료(열람 제한)
        Background : Acanthopanax sessiliflorus (Rupr. et Maxim) Seem, belonging to the Araliaceae family, is widely distributed in Korea, China, and Japan. The plants belonging to Acanthopanax species are traditionally used in Korea as anti-rheumatoid arthritis, anti-inflammatory and anti-diabetic drugs and are recognized to have ginseng-like activities. A simple and sensitive high-performance liquid chromatographic (HPLC) method was developed and validated for independent analysis of major compounds and chlorogenic acid in A. sessiliflorus fruits. Chlorogenic acid was reported that prevent cancer and cardiovascular disease in vivo. Also, it has antioxidant effect in vitro test. In the previous experiment, chlorogenic acid were found in A. sessiliflorus fruits. This study was performed to identification of the major compounds and investigate the method validation for the determination of chlorogenic acid in A. sessiliflorus fruits. Methods and Results : Three major compounds were recorded on a Varian Unity Inova AS-400 FT-NMR spectrometer and analyzed by the new HPLC analysis method. HPLC analysis was carried out using an Waters e2695 and PDA detector. The new analyasis method was validated by the measurement of intra-day, inter-day precision, accuracy, limit of detection (LOD, S/N=3), and limit of quantification (LOQ, S/N=10) of chlorogenic acid. The results showed that the correlation coefficient (R2) for the calibration curves of chlorogenic acid was 0.997 in terms of linearity. The limit of detection (LOD) and limit of quantification (LOQ) were 0.565 ㎍/ml and 2.88 ㎍/ml, respectively. There was no interfering peak observed each other and HPLC system was suitable for analysis showing goodness of peak and high precision. Conclusion : This method is suitable to detect and quantify major compounds in A. sessiliflorus fruits. Furthermore, the result will be applied to establish chlorogenic acid as an standard compound for A. sessiliflorus fruits.
        1 2