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        검색결과 589

        501.
        2014.07 서비스 종료(열람 제한)
        The legume family is the third largest group, including approximately 650 genera and 18,000 species, in the flowering plants and the second important crops to the Poaceae in the agricultural economy. Comparative analysis is a useful tool to understand cross-species genomic structure and alterations during organism’s evolutionary history. In this study, we constructed a composite comparative map of ten legume species, including Medicago truncatula, Medicago sativa, Lens culinaris, Pisum sativum, Lotus japonicus, Cicer arietinum, Vicia faba L, Vigna radiata, Phaseolus vulgaris and Glycine max. Of these species, M. truncatula, which is a representative model system, played a central role to develop the cross-genome amplifiable PCR gene markers for the purpose of transferring them to other related legume species. A total of 140 cross-species core markers were employed to analyze genomic colinearity across this broad array of legume species. The comparative map demonstrates a diverse array of evolutionary events, such as duplications, inversions and reciprocal translocations. It is anticipated that resulting maps would provide a broader insights into the lineage-specific genomic organization of these glalegoid/phaseoloid legumes, which are two clades containing almost all crop legumes of economic importance, and can further used for the molecular breeding through translating genomic information into other orphan legumes.
        502.
        2014.07 서비스 종료(열람 제한)
        Comparative analysis is a typically useful tool for translating genomic information from one species to another. However, currently available softwares are relatively difficult to directly use for researchers that are not familiar with use of bioinformatic tools. Therefore, we intended to develop a new platforms and/or interface through which one can use in more comfortable way, based on the concept of interactive comparative analysis. Towards this direction, we, firstly, constructed relational database to store the information on abiotic stress genes identified from multiple plant species using various resources, such as the TAIR (http://www.arabidopsis.org), gene expression profiles and relevant literatures, and linked with comparative analysis interface. For purposes of comparative analysis and identification of synteny blocks, cross-species orthologous genes were determined using a combination of tBlastX and BlastP homology searches. We adapted and developed a Circos-like format to present resulting comparative maps. Users can readily choose analysis parameters, for example individual genes and specific chromosomes for chosen species, in the pane of analysis DB, which is useful feature to avoid complexity of comparative genomic analysis. This DB-associated comparative analysis tool, developed in this study, will be able to provide customer-friendly interface for comparative analysis and extend its utility across a broader range of plant genomes.
        503.
        2014.07 서비스 종료(열람 제한)
        Susceptible Vitis vinifera responds to Xylella infection with a massive redirection of gene transcription. This transcriptional response is characterized by increased transcripts for phenlypropanoid and flavonoid biosynthesis, ethylene production, adaptation to oxidative stress, and homologs of pathogenesis related (PR) proteins, and decreased transcripts for genes related to photosynthesis. In addition, the results suggest that susceptible genotypes respond to Xylella infection by induction of limited, but inadequate, defense response. We also compared the transcriptional and physiological response of plants treated by pathogen infection, low or moderate water deficit, or a combination of pathogen infection and water deficit. Although the transcriptional response of plants to Xylella infection was distinct from the response of healthy plants to moderate water stress, we observed synergy between water stress and disease, such that water stressed plants exhibit a stronger transcriptional response to the pathogen. This interaction was mirrored at the physiological level for aspects of water relations and photosynthesis, and in terms of the severity of disease symptoms and pathogen colonization, providing a molecular correlation of the classical concept with the disease triangle.
        505.
        2013.08 서비스 종료(열람 제한)
        The spermatogenesis and oogenesis-specific helix-loop-helix transcription factor 2 (Sohlh2) is exclusively expressed in germ cells of male and female gonad. Sohlh2 acts as a transcriptional factor via its specific DNA binding site, E-box to regulate target genes such as Lhx8, Zp genes, Ngn3. Sohlh2 localize in the female oocyte and in the male spermatogonia. However, the regulatory mechanism of Sohlh2 was poorly understood. In this study, we examine the patterns interacting with Sohlh2. First, we performed immunoprecipitation with the antibody against Sohlh2 protein extracts from the testis. Two-dimensional SDS-gel showed sexual distinguishable protein including Fkbp12, 13, 3, 59. Among them, Fkbp3 is a member of the immunophilin protein family, which play a role in immunoregulation and basic cellular processes involving protein folding and trafficking. Protein is a cis-trans prolyl isomerase that binds the immunosuppressants FK506 and rapamycin. It has a higher affinity for rapamycin than for FK506 and thus may be an important target molecule for immunosuppression by rapamycin. In the expression analysis of Fkbp3 is detected in the multiple tissues; intestine, stomach, kidney, spleen, liver, heart, brain, lung, uterus, ovary, testis. Here, we identified that Fkbp3 mRNA is detected in the ovary and testis, kidney, liver, heart, brain, lung. Immunostaning assay shows that Fkbp3 is localized at the spermatogonia in testis. In further studies, in order to confirm the interaction between Fkbp3 and Sohlh2, we will perform immunoprecipitation.
        506.
        2013.08 서비스 종료(열람 제한)
        The spermatogenesis and oogenesis-specific helix-loop-helix transcription factor 2 (Sohlh2) is exclusively expressed in germ cells of male and female gonad. Sohlh2 acts as a transcriptional factor via its specific DNA binding site, E-box to regulate target genes such as Lhx8, Zp genes, Ngn3. Sohlh2 localize in the female oocyte and in the male spermatogonia. In recent studies, Sohlh2 knockout (KO) mice occurs abnormal spermagoenesis resulting in sperm defect. Sohlh2 KO male mice were infertility due to disruption of numerous gene expression. However, the gene profiles of Sohlh2 KO testes were not characterized and the regulatory mechanism of Sohlh2 was poorly understood. In this study, we analyzed the gene profiles and examined the possible mechanism of Sohlh2 in the spermatogenesis. First, we performed histological analysis such as Hematoxylin and eosin stain, Tunel assay, and Immunohistochemistry to show the onset of disruption of Sohlh2 KO testes. These results showed that Sohlh2 KO testes have atrophic seminiferous tubule due to increased apoptosis at 2 weeks old. And then we analyzed the whole gene profiles in the Sohlh2 KO testes at 2 weeks old. We found that 91 genes were regulated at least 5-fold in knockout testes. Among these, several genes are involved in meiotic process. Quantitative-PCR results are shown that several meiotic factors are significantly down-regulated in 2-weeks-old Sohlh2 KO testes compared with that of wild type mice. Through chromosome spreading assay, we observed that the formation of synaptonemal complex of homologous chromosome during the meiosis in Sohlh2 KO testes was not completed. These suggest that Sohlh2 is critical for regulation of numerous factors including meiotic factors either directly or indirectly. Therefore, mis-regulation of meiotic factors at prophase I of meiosis during spermatogenesis leads to disruption of spermatogenesis in Sohlh2 KO testes. Further studies are needed to look at the mechanism of Sohlh2 for regulation of target genes in detail.
        507.
        2013.08 서비스 종료(열람 제한)
        Golden hamsters are seasonal breeders whose reproductive activities are active during summer. Their sexual function is completely suppressed in winter. In oriental society, traditional medicines have been utilized in treating various complaints. One of them is Cynomorium songaricum (CS) whose extract has been used in treating male impotence and sexual dysfunction. We investigated the effects of aqueous CS extract on the process of spermatogenesis in golden hamsters. The animals were divided into 4 groups: long photoperiod (LP) control, short photoperiod (SP) control, and SP animals treated with low or high concentrations of CS. The animals were daily intubated with low (1.25 g/kg) or high (2.50 g/kg) concentrations of the CS aqueous extracts for 8 weeks. The control animals received the vehicle. The volume of testis was measured consecutively from the same animal at 4 week intervals. As results, the LP control animals showed large testes that indicate reproductively active function, but SP control animals displayed remarkably reduced testes that reflect inactive function. The outcomes of the reproductive activity from low concentrations of CS were not conspicuous. And the integral consequences of the reproductive activity from high concentrations of CS treatments were not significant either. But in tracing the individual animals treated with high CS extract, the effects were evidently splitted into dichotomy. In one subgroup small testes were displayed as in SP control animals, but in the other subgroup large testes were demonstrated as in LP control animals, which implies the absolute prevention of regressing activity by SP. These results suggest that the CS extract has a potency to prevent the regressing effects of SP and promotes the male fertility by strengthening the spermatogenesis in the golden hamsters.
        508.
        2013.07 서비스 종료(열람 제한)
        Comparative analysis is a typically useful tool for translating genomic information from one species to another. However, currently available softwares are relatively difficult to directly use for researchers that are not familiar with use of bioinformatic tools. Therefore, we intended to develop a new platforms and/or interface through which one can use in more comfortable way, based on the concept of interactive comparative analysis. Towards this direction, we, firstly, constructed relational database to store the information on abiotic stress genes identified from multiple plant species using various resources, such as the TAIR (http://www.arabidopsis.org), gene expression profiles and relevant literatures, and linked with comparative analysis interface. For purposes of comparative analysis and identification of synteny blocks, cross-species orthologous genes were determined using a combination of tBlastX and BlastP homology searches. We adapted and developed a Circos-like format to present resulting comparative maps. Users can readily choose analysis parameters, for example individual genes and specific chromosomes for chosen species, in the pane of analysis DB, which is useful feature to avoid complexity of comparative genomic analysis. This DB-associated comparative analysis tool, developed in this study, will be able to provide customer-friendly interface for comparative analysis and extend its utility across a broader range of plant genomes.
        509.
        2013.07 서비스 종료(열람 제한)
        Cross-species translation of genomic information may play a crucial role in applying biological knowledge gained from one species to other genomes. To screen and identify a broad range of abiotic stress-responsive genes, we employed a diverse array of resources, including Arabidopsis databases (http://www.arabidopsis.org), expression profiling data and previously reported literatures. As a result, a total of 1,377 genes were identified and classified into 18 different functional criteria based on biological processes of gene ontology. The gene set was translated into M. truncatula, which is a representative model system in the Fabaceae, by identifying orthologous genes between these two genomes with a combination of tBlastx and BlastP analyses. It is shown that approximately 82% of genes were estimated to be translated between the two genomes below the E-value of 10-30. These orthologous loci were used to construct comparative maps by developing a user-friendly analysis platform, resulting in a total of 52 synteny blocks. Furthermore, to discover central genes by which control responses to the abiotic stresses, a combination of AraNet (http://www.functionanet.org) and the Cytoscape program was used for the gene network analysis. The analysis resulted in the identification of 240 potential key genes. We anticipate that these genes may impact molecular breeding programs by discovering trait-associated SNPs followed by marker development.
        510.
        2013.07 서비스 종료(열람 제한)
        Microsatellites are one of the most suitable markers for variety identification as it has great discrimination power for varieties with narrow genetic variation. The polymorphism level between forty microsatellite primer pairs and 148 soybean varieties was investigated through fluorescence based automatic detection system. A set of 16 primer pairs showed highly reproducible and polymorphic in these varieties. A total of 204 alleles were detected by using 16 microsatellite markers. The number of alleles per locus ranged from 6 to 28 with an average of 12.75 alleles per locus. The average polymorphism information content (PIC) was 0.86 ranging from 0.75 to 0.95. Two hundred four microsatellite loci were used to calculate Jaccard’s distance coefficients for unweighted pair group method using the arithmetic averages cluster analysis. These varieties were separated into several distinctive groups corresponding to varietal types. All of the varieties were perfectively discriminated by markers genotypes. This information may be useful to compare through genetic relationship analysis between existing and candidate varieties in distinctive tests and protection of plant breeders’ intellectual properties rights through variety identification.
        511.
        2013.07 서비스 종료(열람 제한)
        The legume family is the third largest group, including approximately 650 genera and 18,000 species, in the flowering plants and the second important crops to the Poaceae in the agricultural economy. Comparative analysis is a useful tool to understand cross-species genomic structure and alterations during organism’s evolutionary history. In this study, we constructed a composite comparative map of ten legume species, including Medicago truncatula, Medicago sativa, Lens culinaris, Pisum sativum, Lotus japonicus, Cicer arietinum, Vicia faba L, Vigna radiata, Phaseolus vulgaris and Glycine max. Of these species, M. truncatula, which is a representative model system, played a central role to develop the cross-genome amplifiable PCR gene markers for the purpose of transferring them to other related legume species. A total of 108 cross-species core markers were employed to analyze genomic colinearity across this broad array of legume species. The comparative map demonstrates a diverse array of evolutionary events, such as duplications, inversions and reciprocal translocations. It is anticipated that resulting maps would provide a broader insights into the lineage-specific genomic organization of these glalegoid/phaseoloid legumes, which are two clades containing almost all crop legumes of economic importance, and can further used for the molecular breeding through translating genomic information into other orphan legumes.
        514.
        2013.03 서비스 종료(열람 제한)
        Cerebral infarction is one of the leading causes of death worldwide and the most common cause of death from a singledisease in South Korea. Each year, 795,000 people in the U.S. experience a new or recurrent stroke. Approximately 15-30% of cerebral infarctions are of embolic origin related to cardiac abnormalities. Because determination of the etiology of cerebral infarction is crucial to acute management and future prevention, clinicians should pay attention to finding the cardiac source of embolism in patients with cerebral infarction. We report on a case of cerebral infarction by a small papillary fibroelastoma on the mitral valve. The patient was treated with open heart surgery and closure of the patent foramen ovale to prevent further embolic events.
        515.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        Korea has adopted a federal renewable electricity standard that begins at 2% in 2012 and requires companies to source 10% of their electricity from renewables by 2022. Therefore the interest in the use of biomass as a renewable energy resource is growing. By importing biomass, the Korea, which produces too little biomass of its own, can meet the needs of the renewable energy sectors. In the case of import biomass, it will cost a great deal on the transportation and logistics of biomass materials. Therefore new research and development on the biomass fuel with high energy density is needed to reduce logistics cost on transportation of the biomass fuel. Torrefaction is a thermochemical treatment process of biomass at temperatures ranging between 200 and 300oC. Typically, 70% of the mass is retained as a char product, containing 90% of the initial energy content. Torrefaction experiments on samples of EFB were performed in a fixed bed reactor to determine the effect of operation variables such as reaction temperature (205-310oC), reaction time (20-40 min) and air ratio (0-0.18) on char yield and characteristics. Increase of the torrefaction temperature led to a decrease of the yield of the char. The heating value of char increased with the increase of the reaction temperature, because the carbon content increased and hydrogen and oxygen content decreased. The yield of char decreased with increasing air ratio. This suggested that oxidation of EFB occurred during torrefaction in the presence of oxygen.
        516.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        In the last several years, South Korea's shipbuilders have been dominating global shipbuilding. Thus, many global suppliers in the shipbuilding industry, especially German supply companies, are eager to get the Korean major shipbuilders as their customer. This study analyzed the different ways of business behaviours of German and Korean businessmen regarding customer-supplier relations. Furthermore, this paper aims to examine the kinds of challenges the international businessmen are confronted with and how this affects everyday business between German suppliers and Korean customers, using several case examples. Finally, backgrounds of cross-cultural problems and conflicts of German-Korean business relations are identified and explained.
        517.
        2012.10 KCI 등재 서비스 종료(열람 제한)
        IPP isomerase (Iso) and Limonene synthase (Limo) are important enzymes in terpenoids biosynthesis pathway. The wild type and each metabolically engineered (Iso and Limo) transgenic spearmint (Mentha spicata Linne) plants were compared for their growth patterns and the contents of essential oil in in vitro culture media. The profile of terpenoid metabolites was obtained from the essential oil of the metabolically engineered transgenic spearmint, which was extracted using a modified SDE method, by GC-MS analysis. The growth of wild spearmint was more profuse in B5 culture medium than in other media. Significant differences in leaf and root growth patterns were observed between metabolically engineered transgenic and wild type spearmint plants. The leaves of the transgenic spearmint plants were slightly elongated but were dramatically narrower than those of wild type spearmints. The content of essential oil of transgenic spearmint was different slightly depending on the target terpenoid genes. The content of essential oils in Limo transgenic plants was higher than that of Iso, except for transgenic plant in B5 medium. The transgenic spearmint produced more terpenoids than the wild type. Iso spearmint extracts showed eleven terpenoids and a phenylpropane, while Limo spearmint extracts contained nine terpenoids. However, extracts from the wild type showed the presence of only four terpenoids.
        518.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        In order to develop a high cellulolytic direct-fed microorganism (DFM) for ruminant productivity improvement, this study isolated cellulolytic bacteria from the rumen of Holstein dairy cows, and compared their cellulolytic abilities via DM degradability, gas production and cellulolytic enzyme activities. Twenty six bacteria were isolated from colonies grown in Dehority’s artificial (DA) medium with 2% agar and cultured in DA medium containing filter paper at 39℃ for 24h. 16s rDNA gene sequencing of four strains from isolated bacteria showed that H8, H20 and H25 strains identified as Ruminococcus flavefaciens, and H23 strain identified as Fibrobacter succinogenes. H20 strain had higher degradability of filter paper compared with others during the incubation. H8 (R. flavefaciens), H20 (R. flavefaciens), H23 (F. succinogenes), H25 (R. flavefaciens) and RF (R. flavefaciens sijpesteijn, ATCC 19208) were cultured in DA medium with filter paper as a single carbon source for 0, 1, 2, 3, 4 and 6 days without shaking at 39℃, respectively. Dry matter degradability rates of H20, H23 and H25 were relatively higher than those of H8 and RF since 2 d incubation. The cumulative gas production of isolated cellulolytic bacteria increased with incubation time. At every incubation time, the gas production was highest in H20 strain. The activities of carboxymethylcellulase (CMCase) and Avicelase in the culture supernatant were significantly higher in H20 strain compared with others at every incubation time (p
        519.
        2012.07 서비스 종료(열람 제한)
        Microsatellite is one of the most suitable markers for variety identification as it has great discrimination power for varieties with narrow genetic variation. The relationship between marker genotypes and 58 melon varieties was analyzed. Of the 400 pairs of simple sequence repeat (SSR) primers screened against 11 melon varieties. 28 pairs showed highly polymorphism on the basis of PIC (Polymorphism Information Contents) value. These markers were applied to constructing DNA profile data base of 58 major melon varieties through multiplex PCR and fluorescence based automatic detection system. A total of 111 polymorphic amplified fragments were obtained by using 28 SSR markers. The average of PIC value was 0.643 ranging from 0.401 to 0.846. One hundred eleven SSR loci were used to calculate Jaccard’s distance coefficients for UPGMA cluster analysis. A clustering group of varieties, based on the results of SSR analysis, were categorized into plant shape and fruit type. Almost all of the varieties were discriminated by marker genotypes. This information may be used to select comparative variety through comparison of genetic relationship between existing variety and candidate varieties in distinctive tests and protection of plant breeders’ intellectual property rights through variety identification.
        520.
        2012.07 서비스 종료(열람 제한)
        For purposes of studying intron structures and predicting consensus splice motifs, a total of 102 legume species were used to isolate introns across the family. Of 196 gene-targeted PCR primer pairs, we successfully amplified 118 intron-containing genes (60.2%) and obtained a total of 1,870 introns with an average size of 143 nucleotides. Species-based compilation of 5’- and 3’-splicing motifs showed lineage-specific conservation in each splicing motif. Compilation of the entire intron set permitted prediction of the consensus sequences of splicing signal motifs in legumes, AYGWGTABABGH and TVNC/TAGGHTV for the 5’- and 3’-splicing motifs, respectively. Interestingly, these consensus motifs are very similar to the corresponding splicing signals of two model systems, Arabidopsis and rice. This result is suggestive of conservation of pre-mRNA splicing mechanisms in higher plants. Multiple alignments of CALTL introns demonstrated that the region from the branch point to 3’ splice site was relatively more conserved than the region from5’ splice site to the branch point. Phylogenetic analysis demonstrated that each of three splicing motifs, 5’-splice sites, 3’-splice sits, and branch site, was relevant to evolutionary divergence of species and phylogenetically informative, suggesting that splice signal sequences would be useful as a potential tool for the molecular phylogenetic analysis.