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        검색결과 988

        561.
        2013.10 구독 인증기관·개인회원 무료
        1-deoxynojirimycin (1-DNJ), a potent a-glycosidase inhibitor, has therapeutic applications in treatments of HIV, Gaucher’s disease, and diabetes. 1-DNJ has been extracted from natural sources (mulberry leaves) for therapeutic purposes; however, 1-DNJ ingredients are in limited supply and are costly to obtain on a large scale. Since certain strains of Bacillus and Streptomyces species reportedly produce 1-DNJ, they may serve as potential sources for high-yield 1-DNJ production. In this study, we obtained evidence for four bacteria that produce 1-DNJ in large quantities by high performance liquid chromatography and thin layer chromatography. Investigation of the effect of mulberry leaves powder concentration(1~5%), using the 1-DNJ high-production bacteria, provided evidence for microbial mass production of 1-DNJ.
        562.
        2013.10 구독 인증기관·개인회원 무료
        Spider community was surveyed at Nakdonggang River which is the longest river (525 km and 23,384 km2) located East-south part of Korea. Nakdonggang river is developing for water management and environmental conservation including restoration of river ecosystem under “The Four-River Restoration Project”. Sampling was made 3 occasions from June to August in 2009. Eight survey sites were selected from both sides of river in Andong, Sangju, Gumi and Seongju prefectures. Spiders were collected with sweep net for on the plants above ground and pitfall traps for on the ground. A total of 94 species of 71 genera in 24 families were identified from 805 collected spiders. Species richness was high in Salticidae (18 species, 19.1%), Araneidae (12 species, 12.8%), Lycosidae (9 species, 9.6%) in order. Wandering spiders (55 species occupied 58.5%, 493 individuals occupied 61.2%) were higher than webbing spiders (39 species occupied 41.5%, 493 individuals occupied 61.2%) in species richness and abundance. Dominant species were Tetragnatha praedonia (Tetragnathidae) and Neoscona adianta (Araneidae) in webbing spiders, and Anahita fauna (Ctenidae), Pirata procurvus (Lycosidae) and Gnaphosa kompirensis (Gnaphosidae) in wandering spiders with abundance. Collectively, most spiders collected from this study were water preferring spiders and showed different community structure compared to other reports from terrestrial spider fauna. Present result will bevaluable to compare the effect of development on the arthropod fauna after completion of the project.
        563.
        2013.10 구독 인증기관·개인회원 무료
        The oriental fruit moth (Grapholita molesta) and the plum fruit moth (G. dimorpha) share the same major sex pheromone components, Z8-dodecenyl acetate (Z8-12Ac) and E8-dodecenyl acetate (E8-12Ac) with different ratio. However, these two congener male species were cross-attracted to the counter sex pheromone traps. For development of the specific monitoring lures, the minor sex pheromone components were added to the major components. G. molesta females emit two minor components of Z8-12OH and 12OH and G. dimorpha females emit four minor of 12Ac, 14Ac, Z8-14Ac, and E8-14Ac. For a specific monitoring lure of G. molesta, only Z8-12Ac major component attracted only G. molesta males, but did not any G. dimorpha. For a specific monitoring lure of G. dimorpha, the addition of Z8-14Ac to the major component (Z8-12Ac:E8-12Ac = 85:15) attracted G. dimorpha males with less than 5% G. molesta males. Other with components (12Ac, 14Ac, and E8-14Ac) was not effective in both trapping efficiency and selectivity.
        564.
        2013.09 구독 인증기관 무료, 개인회원 유료
        Mycoplasma (M.) hyopneumoniae is the causative agent of swine enzootic pneumonia, a disease that is prevalent in every country where pigs are raised. In this study, we aimed to develop a sensitive and specific PCR assay to detect M. hyopneumoniae in pigs. The suitability of this PCR assay for the detection of mycoplasmal infection was also tested using clinical lung samples from slaughtered pigs. We de- veloped a probe and M. hyopneumoniae-specific primer pairs, MhyoP-F and MhyoP-R, for the new PCR assay based on regions in the Mycoplasma protein P97 gene that are unique to M. hyopneumoniae. The developed PCR as- say was very specific and sensitive for the detection of M. hyopneumoniae. The assay was able to detect the equivalent of 10 pg of target template DNA, which indicates that the assay was very sensitive. In addition, the M. hyopneumoniae PCR assay detected only M. hyopneumoniae and no other Mycoplasma spp. or bacterial species of another genera. Further, the newly developed PCR assay effectively detected M. hyopneumoniae infection in pigs. We suggest that this PCR assay using M. hyopneumoniae-specific primer pairs, MhyoP-F and MhyoP-R, will be useful and effective for monitoring M. hyopneumoniae infection in pigs.
        4,000원
        565.
        2013.09 구독 인증기관 무료, 개인회원 유료
        The present study investigated the urinary tract toxicity of melamine alone or in combination with cyanuric acid in rats. Male rats were orally administered melamine alone (800 mg/kg) or melamine plus cyanuric acid (50 mg/kg each) for 3 consecutive days. Although melamine treatment did not show any significant difference in body weight, kid- ney or urinary bladder weight, serum blood urea nitrogen (BUN) or creatinine levels, it caused a decrease in urinary pH and mild histopathological alterations in the kidney and urinary bladder. In contrast, co-administration of melamine and cyanuric acid induced a decrease in body weight, an increase in kidneys and urinary bladder weights, and an elevation in serum BUN and creatinine levels, which were not observed in animals treated with melamine alone. His- topathological examination showed that the incidence and severity of histopathological lesions in the kidney and uri- nary bladder were much higher than those in the melamine group. Urinalysis revealed an increase in urine occult blood, leukocytes and protein and a decrease in urinary pH. These results indicate that concomitant administration of cyanuric acid synergistically potentiated the urinary tract toxicity induced by melamine in rats. In this study, we first demon- strated the synergistic toxic effects of melamine in combina- tion with cyanuric acid on urinary bladder and urinalysis in rats.
        4,000원
        566.
        2013.09 구독 인증기관 무료, 개인회원 유료
        Objective. To investigate the effects of the hypoxia inducible factor-1 (HIF-1) activation–mimicking agent cobalt chloride (CoCl2) on the osteogenic differentiation of human mesenchy-mal stem cells (hMSCs) and elucidate the underlying mole-cular mechanisms. Study design. The dose and exposure periods for CoCl2 in hMSCs were optimized by cell viability assays. After confirmation of CoCl2-induced HIF-1α and vas-cular endothelial growth factor expression in these cells by RT-PCR, the effects of temporary preconditioning with CoCl2 on hMSC osteogenic differentiation were evaluated by RT- PCR analysis of osteogenic gene expression, an alkaline phos-phatase (ALP) activity assay and by alizarin red S staining. Results. Variable CoCl2 dosages (up to 500 µM) and exposure times (up to 7 days) on hMSC had little effect on hMSC survival. After CoCl2 treatment of hMSCs at 100 µM for 24 or 48 hours, followed by culture in osteogenic differentiating media, several osteogenic markers such as Runx-2, osteocal-cin and osteopontin, bone sialoprotein mRNA expression level were found to be up-regulated. Moreover, ALP acti-vity was increased in these treated cells in which an accele-rated osteogenic capacity was also verified by alizarin red S staining. Conclusions. The osteogenic differentiation poten-tial of hMSCs could be preserved and even enhanced by CoCl2 treatment.
        4,000원
        567.
        2013.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The iron oxides nanoparticles and iron oxide with other compounds are of importance in fields including biomedicine, clinical and bio-sensing applications, corrosion resistance, and magnetic properties of materials, catalyst, and geochemical processes etc. In this work we describe the preparation and investigation of the properties of coated magnetic nanoparticles consisting of the iron oxide core and organic modification of the residue. These fine iron oxide nanoparticles were prepared in air environment by the co-precipitation method using of Fe2+ : Fe3+ where chemical pre- cipitation was achieved by adding ammonia aqueous solution with vigorous stirring. During the synthesis of nanoparti- cles with a narrow size distribution, the techniques of separation and powdering of nanoparticles into rather monodisperse fractions are observed. This is done using controlled precipitation of particles from surfactant stabilized solutions in the form organic components. It is desirable to maintain the particle size within pH range, temperature, solution ratio wherein the particle growth is held at a minimum. The iron oxide nanoparticles can be well dispersed in an aqueous solution were prepared by the mentioned co-precipitation method. Besides the iron oxide nanowires were prepared by using similar method. These iron oxide nanoparticles and nanowires have controlled average size and the obtained products were investigated by X-ray diffraction, FESEM and other methods.
        4,000원
        569.
        2013.06 구독 인증기관 무료, 개인회원 유료
        Onion (Allium cepa L.) contains high levels of dietary fibers and antioxidants, including vitamin C, D, and folates. Onion is also known as a quercetin-rich vegetable with high flavonoid content. Onion peel contains over 20 times more quercetin than onion flesh. The aim of this study was to examine the question of whether onion peel extract supplementation has an effect on maximal exercise performance in rat. Onion peel extracts were extracted with hot water. Thirty male Sprague Dawley rats were maintained on a pellet diet for one week, and then randomly divided into five groups: Normal control, Positive control (quercetin 20 mg/kg), Onion peel 4 mg/kg, Onion peel 20 mg/kg, and Onion peel 100 mg/kg. Oral administration was performed daily. The experimental period was four weeks. Thereafter, animals were then forced to swim in water and the maximal exercise performance period from the swimming start time to the exhausted time, in which they failed to rise to the surface of the water to breathe within a 7 second period, was measured. After necropsy, weights of gastrocnemius muscles were measured. Lactate dehydrogenase concentration in serum was measured using an enzymatic method, using a commercial kit. The maximal exercise performance period was significantly longer in the onion peel extracts fed groups, compared with the control group. The lactate dehydrogenase concentration of the onion peel extracts fed groups was significantly lower, compared with the control group. Based on these results, we suggest that onion peel water extract supplementation can enhance exercise capacity caused by the mechanism of decreasing lactate dehydrogenase concentration.
        4,000원
        570.
        2013.06 구독 인증기관 무료, 개인회원 유료
        The objective of this study was to examine the effects of high concentrations of glucose on porcine parthenotes developing in vitro. Addition of 55 mM glucose to the culture medium of embryos at the four-cell-stage significantly inhibited blastocyst formation, resulting in fewer cells in blastocyst-stage embryos and increased levels of apoptosis and autophagy compared to control. Quantitative reverse transcriptase (RT) PCR analysis revealed that the expression of pro-apoptotic genes (Caspase 3, Bax and Bak) and autophagy genes (Atg6 and Atg8/Lc3) were increased significantly by the addition of 55 mM glucose to the culture medium compared to control. MitoTracker Green fluorescence revealed a decrease in the overall mitochondrial mass compared to control. However, the addition of 55 mM glucose had no effect on mRNA expression of the nuclear DNA-encoded mitochondrial-related genes, cytochrome oxidase (Cox) 5a, Cox5b and Cox6b1. These results suggest that hyperglycemia reduced the mitochondrial content of porcine embryos developing in vitro and that this may hinder embryonic development to the blastocyst stage and embryo quality by increasing apoptosis and autophagy in these embryos.
        4,000원
        571.
        2013.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Experts of medicine, philosophy and psychology found that human somatotypes were related to personality or physical characteristics and classified somatotypes into various forms. This study explored the changes and types of somatotyping methods from Before Christ to present day and identified the status of studies of somatotypes in the area of physical therapy. This study covered the methods applied in various majors with a focus on those provided in books and papers of Heath BH. and Carter JEL. Based on the results, there are officially twelve assessment methods. Currently, the method of Heath & Carter is most widely applied. Somatotypes are studied in many areas. It is actively explored in the area of pain physical therapy, thermotherapy and integumentary physical therapy. Also, the soft tissue physical therapy area seeks interdisciplinary studies. This study found that there were various assessment methods in diverse areas. It is likely that continuous studies will develop new assessment methods. It is hoped that in the area of physical therapy, somatotypes shall be applied more amply.
        4,000원
        572.
        2013.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        This study is intended to examine the tDCS and Morris Water maze training in Alzheimer’s disease(AD) rats on Tau protein expression. Experiment groups were divided into four groups and assigned 16 rats to each group. Group Ⅰ was a control group(AD induced by scopolamine); Group Ⅱ was a experimental control group(AD injured by scopolamine and treatment tacrine); Group Ⅲ was a group of tDCS application after AD injured by scopolamine; Group Ⅳ was a group of morris water maze training after AD injured by scopolamine. In cognition test, the outcome of group Ⅱ was significantly lower than the groups(p<.001). and group Ⅲ, Ⅳ were significantly low result at 14 days(p<.05). In histological finding, the experimental groups were destroy of micro vessels and finding of cell atropy and swelling. Group Ⅲ, Ⅳ were decreased in degeneration of liver and kidney cells. In immuno- histochemistric response of BDNF and tau protein in hippocampus, BDNF expression of Group Ⅱ was more increase than the other groups. and increase of BDNF expression was Ⅲ, Ⅳ were higher than group Ⅰ at 21 days. Tau protein expression of Group Ⅱ was more decrease than the other groups. and decrease of Tau protein expression was Ⅲ, Ⅳ were lower than group Ⅰ at 21 days. These result suggest that improved tDCS and morris water maze training after scopolamine induced is associated with dynamically altered expression of BDNF and Tau protein in hippocampus and that is related with cognitive function.
        4,000원
        573.
        2013.05 구독 인증기관·개인회원 무료
        Cordyceps militar is (Clavicipitales) is an edible mushroom which is widely distributed in China, Japan and Korea. Various phytochemical constituents, cordycepin, homocitrully laminoadenosine and sterols have been reported from this source and a wide range of biological activities, including antimicrobial, macrophage activation, anticancer, immune modulatory effects were studied. In a continuing search for bioactive constituents from Korean mushrooms, we performed a phytochemical investigation of the MeOH extract from the fruiting bodies of C. militaris. By repeated column chromatographic separation of the extract, fourteen compounds, were isolated. The identification and structural elucidation of the compound was based on NMR spectral data. anti-aging activities were performed on adriamycin-induced cellular senescence model. Human dermal fibroblasts(HDFs) and human umbilical endothelial cells(HUVECs) treated with adriamycin for inducing aging were used for cytotoxicity and senescence-associated beta-galactosidase(SA-β-gal) activity assay.
        576.
        2013.04 구독 인증기관·개인회원 무료
        Hipparchia autonoe belongs to the family Nymphalidae (Lepidoptera) and is designated as an endangered insect and national monument in Korea. It only inhabits a very restricted area on Mt. Halla but is widely distributed in several Asian countries including Mongolia. A previous study conducted to understand the genetic relationship between Mt. Halla and Mongolian H. autonoe for conservation purposes suffered from a limited number of samples. Therefore, we sequenced the DNA barcode region of an additional 36 H. autonoe individuals, combined them with previous data from 19 individuals, and performed phylogenetic and population genetic analyses. Furthermore, the internal transcribed spacer 2 (ITS2) region was also sequenced from the 36 samples as a nuclear DNA marker. The existence of independent haplotypes, sequence types, and significant FST estimates (p < 0.05) between Mt. Halla and Mongolian populations indicated hampered gene flow between the populations. Nevertheless, an absence of a reciprocal monophyletic group in Mt. Halla and Mongolian populations by cytochrome oxidase subunit I gene- and ITS2-based phylogeny suggests that the genetic isolation of the Mt. Halla population from the Mongolian populations seemed not large enough to consider them independent genetic entities.
        577.
        2013.04 구독 인증기관·개인회원 무료
        The species status of Oeneis urda (Eversmann) and O. mongolica (Oberthür) has been argued based on morphological characters. Reexamination of their major morphological characters has shown a slight differentiation in the two species. Sequences of three mitochondrial genes (COI, ND6, and ND1) and one nuclear region (internal transcribed spacer 2, ITS2) from two O. urda populations (Yangyang and Mt. Hanla) and one O. mongolica population (Uljin) were performed for phylogenetic and population genetic inferences. Sharing of identical sequences in the ND6 gene and ITS2, minimal sequence divergence in the COI and ND1 genes, and phylogenetically undividable sequence types in all mitochondrial genes and ITS2 suggest genetic continuity between the two species. Nevertheless, significant FST estimates (p < 0.05) were found for the COI gene in comparisons between Yangyang (O. urda) and Uljin (O. mongolica), between Yangyang (O. urda) and Mt. Hanla (O. urda), and between Uljin (O. mongolica) and Mt. Hanla (O. urda) populations. These FST estimates, along with other gene-based analyses collectively suggest isolation of the two species at some point in the past, but incomplete separation between the two species on the mainland (Yangyang and Uljin) and biogeographically forced isolation of the O. urda population on Mt. Hanla collectively appear to complicate species status of these two species that were once further clearly separated.
        578.
        2013.04 구독 인증기관·개인회원 무료
        Lepidoptera is one of the largest insect orders, but the phylogenetic relationships within this order, have yet to be completely described. One of the unresolved relationships includes the monophyly of Papilionoidea in relationship with the monotypic superfamily Hesperioidea. We newly sequenced five hesperid mitochondrial genomes (mitogenomes), representing four subfamilies: Pyrginae (Daimio tethys and Lobocla bifasciatus), Coeliadinae (Choaspes benjaminii), and Hesperiinae (Potanthus flavus), and Heteropterinae (Carterocephalus silvicola). Along with these newly sequenced hesperid genomes phylogenetic analysis was conducted with all available lepidopteran mitogenomes including three reported species of Hesperiidae that consisted of ~70 species in ten lepidopteran superfamilies. The test for the effect of optimization schemes, such as exclusion and inclusion of third codon position of 13 PCGs, other genes (22 tRNAs and two rRNAs), and with and without partitions also was performed. Majority of datasets consistently placed the monophyletic Hesperiidae the sister to ((Pieridae + Lycaenidae) + Nymphalidae), placing another true butterfly family Papilionidae as the basal lineage of this group, presenting the relationships (Papilionidae + (Hesperiidae + ((Pieridae + Lycaenidae) + Nymphalidae))). Consistent to previous result, Pyraloidea was placed as the sister to ((Bombycoidea + Geometroidea) + Noctuoidea), placing the Macrolepidoptera as non-monophyletic group.
        579.
        2013.04 구독 인증기관·개인회원 무료
        The bumblebee, Bombus ignitus (Hymenoptera: Apidae), is a valuable natural resource that is widely utilized for greenhouse pollination in South Korea. Understanding the magnitude of genetic diversity and geographic relationships is of fundamental importance for long term preservation and utilization. As a first step, we sequenced a partial COI gene of mitochondrial DNA (mtDNA) corresponding to the “DNA barcode” region and the complete internal transcribed spacer 2 (ITS2) of nuclear ribosomal DNA from 88 individuals collected in nine South Korean localities. The complete ITS2 sequences were longest among known insects, ranging in size from 2,034 bp ~ 2,052 bp, harboring two duplicated 112-bp long repeats. The 658-bp long mtDNA sequences provided only six haplotypes with a maximum sequence divergence of 0.61% (4 bp), whereas the ITS sequences provided 84 sequence types with a maximum sequence divergence of 1.02% (21 sites). The combination of the current COI data with those of published data suggest that the B. ignitus in South Korea and China are genetically a large group, but those in Japan can be roughly separated into another group. Overall, a very high per generation migration ratio, a very low level of genetic fixation, and no discernable hierarchical population were found to exist among the South Korean populations of B. ignitus, which suggests panmixia. This finding is consistent with our understanding of the dispersal capability of the species.
        580.
        2013.04 구독 인증기관·개인회원 무료
        In the present study, the 17,694-bp long complete mitochondrial genome (mitogenome) of the dwarf honey bee, Apis florea (Hymenoptera: Apidae), is described with an emphasis on the noteworthy triplicated tRNAser(AGN) region and an extraordinary long A+T-rich region with repeat regions. The gene arrangement of A. florea mitogenome is identical to that of A. mellifera, but has triplicated tRNASer(AGN), each of which contains the precedent 44 bp-long and following another 64 bp-long repeats plus one complete first repeat abutting to tRNAMet. A total of 1,610-bp long two repeat regions in 1,987 bp-long A+T-rich region is composed of nearly identical 141 ~ 219-bp long five tandem repeats and 50 ~ 52-bp long 12 tandem repeats that are encompassed by three non-repeat sequences. One of the common interpretations for such repeat sequence is slipped-strand mispairing and unequal crossing-over events during DNA replication.