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        검색결과 266

        121.
        2016.10 구독 인증기관·개인회원 무료
        Somatic cell nuclear transfer (SCNT) has been considered for preserving genetically valuable or endangered animals. Sapsaree is a Natianal Monument in Korea to maintian a pure pedigree. The aim of this study was to produce azoospermia Sapsaree using SCNT and identify normal reproductive ability of cloned azoospermia Sapsaree. Ear skin biopsy was performed on a thirteen-year-old azoospermia Sapsaree and ear skin fibroblasts were isolated for SCNT as donor cells. The fibroblasts were injected into enucleated in vivo matured oocytes, the couplets were electrical fused by two pulse of direct current (55 V for 15 μs) using titanium and platinum fusion needle and activated by calcium ionophore. Cloned embryos were surgically transferred into oviducts of natuarally estrus cycle synchronized recipient dogs. The fusion rate of platinum needle was 70%, which was higher than those of titanium needle (64.1%). Developmental rate to the 8 cells and 10 cell stages was higher in platinum needle group (24% and 16%, respectively) than those of platinum needle group (14.8% and 3.1%, respectively). Total 35 SCNT embryos were transferred into oviducts of 3 recipient dogs and one recipient finally delivered a puppy by caesarean section. As results, this study demonstrated that platinum fusion needle could be successfully make the reconstructed embryos and improve the efficiency of canine SCNT. Cloning azoospermia Sapsaree may contribute to conserve genetically valuable and unique pedigree. And further study should be confirm whether cloned live dog is azoospermia.
        122.
        2016.10 구독 인증기관·개인회원 무료
        The cancer and Parkinson's disease associated protein DJ-1 is multifunctional protein that involves in diverse cellular process. DJ-1 protein has a cellular protective role and promoted cell survival under an oxidative stress. However, the cellular protective mechanism of DJ-1 is not fully understand, and we needs to be further study their functions in novel organisms. In the present study, we investigated the protective role of DJ-1 against induced oxidative stress in canine cell line. On the basis of these experiments, canine DJ-1 overexpressing and null cell lines were established. The stable overexpression and down regulation of DJ-1 efficiency confirmed by the western blot analysis. Subsequently, the DJ-1 gene transfected cell lines and control cells were subjected to induced the oxidative stress, and then cell viability, cell proliferation assay, cellular apoptosis detection analysis (Annexin V and TUNEL assay), intracellular ROS and mitochondrial activity were measured appropriately. The results showed that DJ-1 overexpressed cells were up-regulated cell viability under oxidative stress conditions induced by the rotenone and hydrogen peroxide (H2O2), whereas loss of DJ-1 cells were down-regulated the cell survival activity. Additionally, overexpression of DJ-1 cells increased cell resistance to oxidative stress and inhibited the elevation of cell death and cellular ROS induced apoptosis. Moreover, DJ-1 overexpressed cells was increased mitochondrial functions by using confocal microscopy with MitoTracker staining. On the contrary to this, DJ-1 null cells show defective cellular protection and mitochondria activity against oxidative stress conditions. Our data indicate that canine DJ-1 protein attenuates cellular apoptosis and ROS generation, enhances the cellular survival activity and promote mitochondrial function under the oxidative stress, likewise other mammalian cells. Importantly, DJ-1 overexpression may be an important part of a protective strategy as a sensor for oxidative stress.
        123.
        2016.04 구독 인증기관·개인회원 무료
        Distillers dried grain (DDG) and makgeolli spent grain (MSG) are agricultural by-product to produce alcoholic beverage. However, they are known to contain enough nutrients. Mealworm is a promising insect resource for an animal feed ingredient as well as alternative human food. With low cost, DDG and MSG were investigated as a feed ingredient for rearing high quality mealworms. DDG and MSG were mixed with wheat bran and compared to control feed (only wheat bran) for its effects on larval survivorship, larval weight, duration for larval development, pupation rate, and pupal weight. Adding DDG on wheat bran showed positive results for larval weight, duration for larval developmental period, and pupation rate. However, adding MSG made longer duration for larval development, but it also improved larval weight, pupal weight with more than 90% pupation rate. We confirmed that adding 30~50% of DDG or MSG to conventional wheat bran have a strong potential to replace the conventional wheat bran insect feed for quality insect production.
        127.
        2015.10 구독 인증기관·개인회원 무료
        Insect is an important player in the ecosystem as a prey for animals. Moreover, they are a valuable candidate food source for rearing animal. Tenebrio molitor (Coeloptera: Tenebrionidae) larvae are known as a good food source with high protein, unsaturated fatty acid, minerals. Therefore, it has strong potential to substitute the conventional meat consumption. To utilize T. molitor as a feed, the standard mass-rearing protocol is required. To make standard mass-rearing protocol, we tested different temperature(17.5, 20, 22.5, 25, 27.5 and 30°C) conditions for egg, larvae, pupae and adult T. molitor to identify the optimal rearing condition. Hatching was occurred within 15~32.5°C range. However, 17.5~27.5°C was required to get more than 70 % hatching rete. When the eggs were treated in 22.5~27.5°C, all eggs were hatched within 10 days. As larval development, shorter developmental period, higher pupation and eclosion rates were observed within 25~27.5°C temperature range. In addition, we compared the number of egg, oviposition duration and time required to start egg-laying. The minimum egg-laying(258.40±10.86) was observed at 17.5°C, but the maximum(749.10±7.45) was at 27.5°C. The maximum oviposition duration (137.00±12.73 day (mean±S.D.)) was achieved at 27.5°C, but the minimum (87.50±3.54 day (mean±S.D.)) was at 30°C. The time required to start egg-laying was less than 10 days at 17.5, 27.5, and 30°C. To consider all the factors, we concluded that the optimal temperature is 27.5 °C.
        128.
        2015.06 구독 인증기관·개인회원 무료
        The online store attributes acts as an important trigger for e-impulse buying. Purchasing apparel products are often affected by irrational and emotional attraction making them one of the most frequent impulsively purchased items online. Triggered by ease access to products, easy purchasing, lack of social pressures and absence of delivery efforts, impulse buying occurs in approximately forty percent of all online expenditures. Impulse buying occurs when consumers experience an urge to buy a product, without thoughtful consideration why and for what reason one needs the product. However, few efforts have been made to identify the relationship among-store services attributes, emotions, browsing, urges to buy, and e-impulse buying of apparel products. The objectives of this study was to estimate a path model analysis for causative relationship among e-store service attributes, emotions, browsing, urges to buy, and e-impulse of apparel products. The instrument was developed based on the previous literatures (Park, et al., 2012; Verhagen & Dolen, 2011; Yang & Peterson, 2004)and each item was measured by five-point Liker type scales. A total of 250 data were collected during a regularly scheduled class in universities. More than half of the respondents (65.5%) were 18 to 21 years old. Nearly 65.5 percent of the subjects were women, and more than half of the respondents (63.8%) were below the sophomore. The path model analysis was conducted by AMOS 18.0 using a correlation matrix with maximum likelihood approach. An exploratory factor analysis revealed three types of e-store service attributes: Accuracy, Reliability, and Ease of use. The path model, which was estimated to examine causal relationships among variables (i.e. three types of e-store service attributes, emotions, browsing, urges to buy, and e-impulse buying), was relatively acceptable (chi-square value = 34.40, df = 13, p = .001; GFI = .98, AGFI = .93, RMR = .03). Cronbach's alphas were ranged between .83 and .87. This result suggests that emotions (e.g., positive and negative), browsing and urges to buy perceived by shoppers play important roles as mediators of the e-impulse buying of apparel products. Especially, the urge to buy apparel products was the most important mediator to trigger e-impulse buying. The consumers perceived the accuracy and reliability of e-store attributes were the more perceiving the urges to buy apparel products through the more positive emotions and then the more browsing at e-store. Also, the more ease to use of e-store perceived the more urges to buy apparel products. The more perceiving urges to buy at e-store were the more e-impulse buying of apparel products. This study provides retail managerial implications for stimulating e-shoppers' impulse buying of apparel products.
        129.
        2014.10 구독 인증기관·개인회원 무료
        The spotted-wing drosophila (SWD), Drosophila suzukii (Diptera: Drosophilidae), was originally observed in a few Asian countries, but is now found even in North America and Europe. Genetic information on geographic variation and relationship may broaden our understanding of origin and migration. As a first step, in this study, a portion of mitochondrial COI gene was sequenced to understand genetic relationship and diversity in Korea. Sequencing of 104 individuals provided 57 haplotypes, with the maximum sequence divergence of 1.5%, suggesting high haplotype diversity and moderate sequence divergence. Comparison to GenBankregistered D. suzukii haplotypes (possibly from Spain, Portugal, USA) has shown 100% sequence identity to most of the haplotypes found in this study, but two USA sequences were found to be independent haplotypes, with the sequence divergence ranging from 0.5% ~ 1.4% from our samples in the 553-bp comparison. Phylogenetically, no separable group was found, but, population genetically, the only Chinese population, Sandong, was significantly differentiated (p < 0.05) from all Korean populations, without sharing any haplotype. Among 28 pairwise comparisons of Korean populations only two comparisons showed a significant genetic differentiation, indicating that no population in Korea is completely isolated. Geographically, one haplotype (SWDBA06) was relatively widespread (five among nine localities) and a few haplotypes were found in more than one locality, but most haplotypes were restricted in a locality as a single individual. Overall, high rate of per generation female migration (Nm = 0.75 ~ infinite) and low level of geographic separation (FST=0~0.40) among localities were characteristic. Current data is limited mainly to Korean localities, thus, an expanded study may provide further scrutinized analysis for the fly.
        130.
        2014.10 구독 인증기관·개인회원 무료
        Insect pollinators of the endanger orchid Cypripedium japonicum were surveyed and identified during two years, as a part of a conservation project of the orchid at Jukyeup-san and Hwaak-san (Mt.), South Korea. In total 40 individuals of 16 species in 4 families were identified. The dominant family was Halictidae, and Lasioglossum exiliceps Vachal visited the most frequently C. japonicum during the surveys. The average visiting frequency was 2.5 individuals per hour and the highest 4.3, from 12:00 – 13:00 in a day. After 15:00 insects did not visit the flowers at all. However, all of the visiting insects were found to not carry a pollinium or pollens of the orchard on their bodies; pollen carryover by any of the visiting insects did not occur at all. The orchid seems to require certain pollinators in particular body thickness due to its unique pollination mechanism. The orchid has two exit route openings, around 1 cm in diametre, where the entrapped insects can exit and an anther is situated just in front of each opening. It was inferred that a pollen carrier should be around 1 cm in body thickness. Therefore, the candidate species as the proper pollen carriers can be Tetralonia nipponensis Perez, Xylocopa appendiculata circumvolans Smith and Bombus consobrinus Dahlbom among the surveyed visitors.
        131.
        2013.12 구독 인증기관 무료, 개인회원 유료
        The anti-proliferative efficacy of t,t-conjugated linoleic acid (t,t-CLA), c9,t11-CLA, and t10,c12-CLA was compared in several human cancer cell lines. Gastric NCI-N87, liver Hep3B, pancreas Capan-2, and lung NCI-H522 cancer cells were incubated with 50 μM CLA isomers over a period of 6 days. The t,t-CLA inhibited the growth of all cancer cell lines to different extents, but c9,t11-CLA and t10,c12-CLA inhibited or stimulated the growth of the cancer cell lines. NCI-N87 cells were the most sensitive to growth inhibition and apoptosis from all CLA isomers tested. In NCI-N87 cells, CLA isomers reduced the release of arachidonic acid (AA) via the inhibition of cytosolic phospholipase A2 (cPLA2 ) activity, consequently reducing the production of PGE2 through the inhibition of cyclooxygenase-2 (COX-2). The efficacies of CLA isomers were in the following order (from most to least effective): t,t-CLA, t10,c12-CLA and c9,t11-CLA. Overall, these results imply that the anti-proliferative efficacy of t,t-CLA on cancer cells, especially NCI-N87 cells, was greater than other CLA isomers due to its induction of apoptosis through the inhibition of cPLA2 and COX-2 activities.
        4,000원
        132.
        2013.10 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The fact that flip-flops, one of many different types of unstable shoes, are light and relatively easy to put on, accounts for their popularity among people. But because flip-flops rely heavily on the support of a single thong between your first and second toes, they impose a huge amount of pressure onto lower leg. Thus in the following experiment we tried to examine the different effects of flip-flops and running shoes in terms of their effect on muscle activity and fatigue of tibialis anterior and gastrocnemius during walking. In order to measure an electromyogram we used Free EMG system. 10 men and 10 women in running shoes ran on treadmills for 15 minutes at 4.8km/h, 2 days later the same experiment was carried out, but this time, in flip-flops. p value turned out to be greater than .05 and thus there was no considerable difference between the effects of flip-flops and running shoes on muscle activity and fatigue during walking. Therefore we conclude that despite the fact that flip-flops are considered unstable, their effects on muscle activity and fatigue of tibialis anterior and gastrocnemius are negligible.
        3,000원
        133.
        2013.04 구독 인증기관·개인회원 무료
        Escape pattern of the ambrosia beetle Platypus koryoensis (Murayama) based on individual gallery was investigated. The survey was conducted in four oak forests located in Chuncheon, Hanam, Paju and Seongnam, and escape patterns from individual gallery were surveyed using emergence trap attached at the entrances of galleries formed in 2010. The number of adults caught in each trap was periodically counted from May 2011 to September 2012. The adults ambrosia beetle was caught over two years after infestation. The escape patterns in the first and second year after infestation showed different types; in the first year, escape of adults from gallery was observed one or two times whereas escape from gallery was observed two times in the second year with variation in aspect of escape density and timing. Moreover, variations in escape pattern between trees or between galleries in the same tree was observed. Colonization success rate in living tree was higher than that of dead tree, but the number of progeny per gallery in living tree was lower than that of dead tree. Colonization success rate in the galleries of second year was lower than that of first year, but the number of progeny per gallery of second year was higher than that of first year.
        134.
        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.
        135.
        2013.04 구독 인증기관·개인회원 무료
        Mealworms, Tenebrio molitor (L.) is used as an important animal feed additive for growth promotion and health management, but potentially exposes to fungal infection. In this work, virulence of two species of entomopathogenic fungi against the insect, and the relationship between abiotic features and virulence were investigated. Secondly our consideration was also given to the effect of chemical fungicides on conidial germination for risk control. Between Beauveria bassiana (Bb) and Metarhizium roberstii (Mr) (previously M. anisopliae), Bb isolates had much higher virulence (~100% mortality in 3~4 days after the treatment), rather than Mr isolates in laboratory assays. Next, fungus-treated mealworms were kept at wheat bran at 20, 25, 30 and 35℃ with 3, 6, 9 times of water spray to the feeds for set-up of different humidity conditions. Inoculation of fungi to mealworms was conducted by fungal spray and feeding methods, which resulted in higher virulence in feeding method. In the feeding method, all temperature treatments except 35℃ showed high virulence against mealworms, but any significant relationship between virulence and humidity was not observed. In the chemical fungicide screening, fluazinam (CAS No. 79622-59-6) and mancozeb (8018-01-7) significantly inhibited the germination of Bb and Mr conidia. This work suggest that contamination of wheat bran with fungal pathogens, particularly B. bassiana may induce mycosis of mealworms, but introduction of effective fungicides possibly reduce fungal infection.
        136.
        2013.04 구독 인증기관·개인회원 무료
        Beauveria bassiana isolates have been used in integrated pest management, but little consideration has been given to the studies on fungal gene expressions and their functions. In this work, to determine the functions of genes, B. bassiana ERL1170 was transformed by restriction enzyme-mediated integration method, where pABeG with bar gene was used as a transformation vector. Among seven hundred of transformants, morphologically different ERL1170-pABeG-#160 transformant, particularly dysfunctional in conidiogenesis. The transformant had yellow hyphal growth on fourth strength Sabouraud dextrose agar (SDA/4) and produced very small amount of conidia (<1.0×105 conidia/cm2 agar) in 7 days, whereas wild type had white mycelial growth and significantly greater conidia (3.6×106 conidia/cm2 agar). Additionally under microscopic observation, hyphae of #160 seemed like indian club, compared to the straight forms of wild type hyphae. The next work is figure out possible genes contributing the conidiogenesis of B. bassiana.
        140.
        2012.06 구독 인증기관·개인회원 무료
        True hermaphrodites are animals of equivocal sex in which both male and female gonads develop simultaneously. The frequency of true hermaphroditism is higher in pigs than in other domestic animals. Two Korean pigs were diagnosed with true hermaphroditism showing ovotestes, epididymes, penes, and uteri. Histomorphologically, the testicular tissues consisted of Sertoli cells that were devoid of spermatogenic germ cells and showed proliferation of interstitial cells. However, the uteri were of normal architecture and had well-developed uterine endometrial glands. The samples were 38, XX female karyotype without the sex-determining region Y (SRY) gene. The findings of this study could contribute to the understanding of true hermaphroditism in the Korean pig industry. * This work was supported by a grant (Code# PJ008148) from BioGreen21 Program, Rural Development Administration, Republic of Korea.