검색결과

검색조건
좁혀보기
검색필터
결과 내 재검색

간행물

    분야

      발행연도

      -

        검색결과 116

        62.
        2018.04 구독 인증기관·개인회원 무료
        The common bed bug, Cimex lectularius, possesses a cholinesterase expressed exclusively in the salivary gland (ClSChE). In this paper, we investigated the molecular structure, tissue distribution patterns, and biochemical properties of ClSChE and showed that ClSChE exists as a soluble monomeric form or a soluble dimeric form connected by a disulfide bridge. Immunohistochemical analysis confirmed that ClSChE was expressed in the epithelial cells of both the salivary gland and the duct. In addition, the secretion of monomeric ClSChE through the proboscis during feeding was detected by western blotting using a ClSChE-specific antibody. To predict the role of ClSChE injected into the tissue of an animal host, we analyzed the extent of sequestration and hydrolysis of acetylcholine (ACh)/choline (Ch) by ClSChE by ultra-performance liquid chromatography-tandem mass spectrometry. Kinetic analysis revealed that ClSChE possesses extremely low Km (high affinity to ACh) and Vmax values. These findings suggest that ClSChE functions as a sequestering enzyme specific to ACh (not to Ch) by having a very strong affinity to ACh but an extremely long turnover time.
        63.
        2017.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Porcine spermatogonial stem cells (SSCs) prefer three-dimensional (3D) culture systems to 2D ones for the maintenance of self-renewal. Of the many 3D culture systems, agar-based hydrogels are candidates for supporting porcine SSC self-renewal, and there are various types of agar powder that can be used. In this study, we sought to identify an agar-based 3D hydrogel system that exhibited strong efficacy in the maintenance of porcine SSC self-renewal. First, 3D hydrogels with different mechanics were prepared with various concentrations of Bacto agar, lysogeny broth (LB) agar, and agarose powder, and the 3D hydrogel with the strongest alkaline phosphatase (AP) activity and greatest increase in colony size was identified for the different types of agar powder. Second, among the porcine SSCs cultured in the different 3D hydrogels, we analyzed the colony formation, morphology, and size; AP activity; and transcription and translation of porcine SSC-related genes, and these were compared to determine the optimal 3D hydrogel system for the maintenance of porcine SSC self-renewal. We found that 0.6% (w/v) Bacto agar-, 1% (w/v) LB agar-, and 0.2% (w/v) agarose-based 3D hydrogels showed the strongest maintenance of AP activity and the most pronounced increase in colony size in the culture of porcine SSCs. Moreover, among these hydrogels, the strongest transcription and translation of porcine SSC-related genes and largest colony size were detected in porcine SSCs cultured in the 0.2% (w/v) agarose-based 3D hydrogel, whereas there were no significant differences in colony formation and morphology. These results demonstrate that the 0.2% (w/v) agarose-based 3D hydrogel can be effectively used for the maintenance of porcine SSC self-renewal.
        4,000원
        64.
        2017.10 구독 인증기관·개인회원 무료
        The members of the genus Flavivirus are noteworthy, as they cause infectious diseases in humans, such as Zika, denguefever, yellow fever, West Nile, and Japanese encephalitis. Due to the increased awareness of the public health risk posedby flavivirus-infected mosquitoes, mosquito collections were performed in six urban parks of South Korea, as the parksare designated for human recreation but also provide suitable habitats for mosquitoes. We examined the diversity andabundance of mosquito species and conducted molecular diagnostics for the detection of flavivirus infections. Monthlycollections were carried out in each park from March to August in 2017. A total of 4,851 mosquitoes (5 genera and13 species) were collected using BG-sentinel traps and then investigated for flavivirus infections. Pathogenic flavivirusinfections causing human diseases were not observed in the field-collected mosquitoes. However, insect-specific flavivirus(ISF) infections were detected in several mosquito pools. ISF has been previously known to enhance or suppress the replicationof medically important flaviviruses in co-infected mosquito cells. In this study, partial sequences of ISF were analyzed.However, further studies are needed in order to determine its genetic characterization and biological function in vivo.
        65.
        2017.09 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The organic light-emitting diodes are fabricated with six anthracene derivatives containing simple substituents such as phenyl or naphthyl group. The device structure is as in the following: Indium tin oxide (ITO) (180 nm)/4,4-4,4`,4``-tris[N-(1-naphthyl)-Nphenylamino] triphenylamine (2-TNATA) (30 nm)/4,4`-bis[N-(1-naphthyl)-N-phenyl-1-amino] biphenyl (NPB) (20 nm)/Emitting compound (30 nm)/2,2′,2"- (1,3,5-Benzinetriyl)-tris (1-phenyl-1-H–benz-imidazole) TPBi (40 nm)/lithium quinolate (Liq) (2 nm)/Al (100 nm). In the emitting layer the anthracene derivatives are used without any dopant. All the six devices show blue emissions. Among the tested diodes, the one with 9-(2-naphthyl)-10-(p-tolyl) anthracene (2-NTA) exhibited luminous efficiency, power and external quantum efficiencies of 3.26 cd/A, 0.98 lm/A, 2.8 % at 20 mA/cm .
        4,000원
        66.
        2017.07 구독 인증기관·개인회원 무료
        Today, consumers are becoming more sensitive to price since price have been an essential motivation for them to choose the electronic retail venue. Recently, it is recognized that social commerce, with higher rate of daily active users, is ahead of traditional electronic mobile commerce in Korea. One of strengths in social commerce is attractive price deals for fashion brands, which positively lead to purchase probabilities. Therefore, fashion retailers should understand consumers’ price perception and their responses toward sales promotions on the social commerce. The purpose of this study is to examine the effect of consumer price perception and choice heuristics on impulse buying behavior for sales promotion of fashion brands and to examine the moderating effect of an engagement level in the social commerce. A self-administered questionnaire was developed, and mainly included consumer price perception (e.g., price consciousness, sales proneness), choice heuristics (e.g., affect referral, price referral), engagement, impulse buying and demographics. An online survey was undertaken by a research agency. A total of 235 usable responses were obtained from Korean consumers who had purchased fashion brands from social commerce sites (e.g., Coupang, Wemakeprice, Ticketmonster, etc.) using mobile devices. Respondents represent more females (n=129, 54.9%) than males (n=106, 45.1%). They are aged from 19 to 39 years old (Means=29). Results showed that consumers’ sales proneness had a positive effect on affect referral and price referral heuristics, which positively lead to impulse buying behavior. However, consumer price consciousness had a negative effect on impulse buying at the social commerce sites. Also, the mediating effect of the engagement was significant in the relationship among sales proneness, choice heuristics, and impulse buying behavior for sales promotion of fashion brands in the social commerce sites. This study discussed marketing implications for social commerce to effectively manage promotional program in the social commerce market.
        67.
        2017.06 구독 인증기관 무료, 개인회원 유료
        Selecting an appropriate antigen with optimal immunogenicity and physicochemical properties is a pivotal factor to develop a protein based subunit vaccine. Despite rapid progress in modern molecular cloning and recombinant protein technology, there remains a huge challenge for purifying and using protein antigens rich in hydrophobic domains, such as membrane associated proteins. To overcome current limitations using hydrophobic proteins as vaccine antigens, we adopted in silico analyses which included bioinformatic prediction and sequence-based protein 3D structure modeling, to develop a novel periodontitis subunit vaccine against the outer membrane protein FomA of Fusobacterium nucleatum. To generate an optimal antigen candidate, we predicted hydrophilicity and B cell epitope parameter by querying to web-based databases, and designed a truncated FomA (tFomA) candidate with better solubility and preserved B cell epitopes. The truncated recombinant protein was engineered to expose epitopes on the surface through simulating amino acid sequence-based 3D folding in aqueous environment. The recombinant tFomA was further expressed and purified, and its immunological properties were evaluated. In the mice intranasal vaccination study, tFomA significantly induced antigen-specific IgG and sIgA responses in both systemic and oral-mucosal compartments, respectively. Our results testify that intelligent in silico designing of antigens provide amenable vaccine epitopes from hard-to-manufacture hydrophobic domain rich microbial antigens.
        4,000원
        68.
        2017.04 구독 인증기관·개인회원 무료
        Aedes albopictus is one species of mosquito transmitting flavivirus causing Dengue, Zika, and West Nile fever. Although it is an important disease vector, the genetic study of Ae. alpopictus populations has not been undertaken yet in South Korea. Here, we investigated the genetic variation of 99 Ae. albopictus individuals collected from 29 sites in nine provinces in 2016, through mitochondrial COI gene analysis. Haplotype analyses revealed seven haplogroups in South Korea. The main haplogroup, comprising 76 individuals (77.8%), was genetically identical to the one from Nagasaki. Two groups from Jeju Island (11) and the southern coast of South Korea (nine) were closely related to different Ae. albopictus strains from Kumamoto and Guangdong/Fujian, respectively. However, the others (four) were distinct from these two countries. No geographic divisions of populations were found in the study regions. The results suggest the possibility that the currently prevalent Ae. albopictus in South Korea, represents a part of the descendants that originated from nearby countries. However, more comprehensive investigations are needed to explain its movement routes.
        70.
        2016.04 구독 인증기관·개인회원 무료
        Brachymystax lenok tsinlingensis (family Salmonidae), cold freshwater fish, is endemic to Asia. This species is currently distributed throughout Russia, Mongolia, China and the Korean Peninsula. B. lenok tsinlingensis in South Korea was severely affected by anthropogenic activities such as habitat destruction, agricultural run-off and water pollution, and hence this fish has recently been dramatically decreased in its population sizes and become now critically endangered. To recover the number of individuals of B. lenok tsinlingensis, stocking or translocation programs have been conducted continuously by local governments since 1970s. However, these programs made little effort to clarify populations that may have originated from stocked, translocated or introduced fish. An understanding of genetic characteristics of endangered populations is critical to develop effective conservation and restoration plans especially because genetic diversity ensues their future fate. Therefore, we assessed the “conservation status” of this species by estimating the level of genetic diversity and genetic structure among ten geographic populations including restored populations via reinforcement and supplementation. Also, we aimed to trace the genetic origins of the newly translocated population (Chiak) through a restoration practice program. Moreover, we inferred the phylogenetic relationships among Korean lenok populations as well as across the Northeast Asia. Two hundred eighteen individuals of B. lenok tsinlingensis were sampled from ten localities (Yanggu, Injae, Seorak, Bangtae and Hongcheon: North Han River basin; Pyeongchang, Chiak and Jeongseon: South Han River basin; Taebaek and Bonghwa: Nakdong River basin in South Korea). Based on mitochondrial DNA (mtDNA) control region and eight nuclear microsatellite loci, we found extremely low levels of within-population genetic diversity, which suggests small effective population sizes (Ne) within populations. For mtDNA control region, each population housed one, or at most, two haplotypes that are restricted to the respective localities, meaning that these ‘genetically unique’ lineages will be lost permanently if the local populations undergo extinction. The overall values of haplotype diversity (h) and nucleotide diversity (π) for the entire Korean population were 0.703 ± 0.024 and 0.021 ± 0.010, respectively. In the case of microsatellites, average number of alleles across the eight loci for the entire population was 9.1 and allelic richness (AR) per population ranged from 2.375 to 4.144 (mean = 3.104). The values of observed heterozygosity (HO) and expected heterozygosity (HE) were similar to each other [HO: 0.400 ~ 0.590 (mean = 0.518); HE: 0.407 ~ 0.608 (mean = 0.504)]. The inbreeding coefficient (FIS) values were generally low, ranging from 0.048 to 0.279. Consequently, the majority of the populations (except Yanggu and Pyeongchang) were not significantly deviated from Hardy-Weinberg equilibrium (HWE), suggesting random mating at these loci tested. In addition, we found that Korean lenok populations were significantly genetically isolated from each other, with private mtDNA haplotypes and microsatellite alleles, indicating limited gene flow among populations, strong effects of genetic drift due to small Ne, or a combination of both. The Mantel test of microsatellites revealed a significant correlation (r = 0.414, P = 0.04) between genetic and geographic distances for pairwise comparisons among the ten populations, while that of mtDNA showed a lack of correlation. Given the shared identical mtDNA haplotype and similar microsatellite allelic distributions between Chiak and Hongcheon populations, we suggest that the restored (introduced) Chiak population would be inferred to be genetically originated from Hongcheon population. Phylogenetic relationships among Northeast Asian populations showed that South Korean lineages have more recently diverged from China (Yellow River), than between North Korea and Russia. Although the phylogenetic relationship would be expected to be associated with geography, South-North Korea and China populations with a similar latitude was more phylogenetically closely related. These findings may suggest a possible scenario for the historical movements of B. lenok tsinlingensis in Northeast Asia during Last Glacial Maximum (LGM). It would be supported by the line of evidence that most lenok populations migrated to southward from Northern Asia such as Russia and Mongolia during LGM because the Korean Peninsula was landlocked as inland epoch and functioned as a southern shelter with Yellow River. For this reason, the Korean Peninsula is suggested to be an important geographical region for better understanding phylogenetic relationships and evolutionary histories of B. lenok tsinlingensis across the Northeast Asia. Despite large efforts made to develop several restoration programs in South Korea for B. lenok tsinlingensis, it is still unknown whether these past restoration efforts were successful or fruitless, mainly because of little attention paid to post-restoration monitoring research. Hence, there was a lack of their published official records. In the future, conservation and restoration projects of the Korean lenok populations should consider the genetic data for a better understanding of their ecological and evolutionary trajectories. And finally, we hope that our findings here can help inform on the future effective conservation and restoration plans for B. lenok tsinlingensis populatio ns in South Korea.
        71.
        2016.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The purpose of this study was to investigate the effects of core strengthening training on baseball throwing. A total of 14 subjects were recruited from among middle school baseball players. The main outcome measures were as follows: speed guns were used to measure the velocity of baseballs thrown; scored targets were used to measure throwing accuracy; and 50m measuring tapes were used to measure throwing distances. It was found that core strengthening training improved the velocity of baseballs thrown and throwing accuracy and distance. Thus, core strengthening training is effective for improving the throwing ability of baseball players.
        4,000원
        75.
        2014.10 구독 인증기관·개인회원 무료
        RDA(Rural Development Administration of Agriculture) and YIRI(Yecheon-gun Industrial Insect Research Institute) was development of 3 strains crossbred honey bee(Apis mellifera) for increasing honey production(HP). The overall goal of this research is to improve the honey production of queen honey bees. This will enhance the economic value of the nation’s honey bees for honey production, and hazard resistance. Our main objective of this research is to test of honey bees(A. mellifera) that have increased as well as being good honey producers and resistance of disease in jeon-nam province. The new honey bee(A. mellifera) stock were identified ability of increasing honey production by comparing with rearing practice colony. The new honey bee(A. mellifera) stock can produce more than 30~50% honey(HP; 12.31 kg) comparing with rearing practice colonies(control 1; 8.17 kg, and control 2; 9.53 kg). Furthermore, we are calculated the number of worker bee per colony. Population of worker bee in new honey bee(A. mellifera) stock are 2,849 (colony 1), 8,860 (colony 2) and 10,451 (colony 3), it was more then 1.2~3.7 fold comparing with controls.
        76.
        2014.06 구독 인증기관 무료, 개인회원 유료
        Despite many researches related with in-vitro culture of porcine spematogonial stem cells (SSCs), adherent culture system widely used has shown a limitation in the maintenance of porcine SSC self-renewal. Therefore, in order to overcome this obstacle, suspension culture, which is known to have numerous advantage over adherent culture, was applied to the culture of porcine SSCs. Porcine SSCs retrieved from neonatal testes were suspension-cultured for 5 days or 20 days, and characteristics of suspension-cultured porcine SSCs including proliferation, alkaline phosphatase (AP) activity, and self-renewal-specific gene expression were investigated and compared with those of adherent-cul-tured porcine SSCs. As the results, the suspension-cultured porcine SSCs showed entirely non-proliferative and significantly higher rate of AP-positive cells and expression of self-renewal-specific genes than the adherent-cultured porcine SSCs. In addition, long-term culture of porcine SSCs in suspension condition induced significant decrease in the yield of AP staining-positive cells on post-day 10 of culture. These results showed that suspension culture was inappropriate to culture porcine SSCs, because the culture of porcine SSCs in suspension condition didn’t stimulate proliferation and maintain AP activity of porcine SSCs, regardless of culture periods.
        4,000원
        77.
        2012.06 구독 인증기관·개인회원 무료
        In the present study, we investigated the effect of porcine follicular fluid (PFF) concentration (10% vs. 1%) and protein-free media (PFF 0%) on maturation of porcine oocytes in vitro and analysed difference in gene expression in resulting blastocysts following parthenogenetic activation. Three groups were tested; 1) 10% PFF: Tissue culture medium (TCM) 199+10% PFF; 2) 1% PFF: TCM 199+1% PFF; and 3) 0.1% PVA: TCM 199+0.1 PVA. Cumulus-oocyte-complexes were cultured in the respective media containing gonadotrophin (1 ug/ml), epidermal growth factor (10 ng/ml), cystein (0.57 mM), sodium pyruvate (0.91 mM), insulin (5 ug/ml), 9-cis retinoic acid (5 nM) for 20~22 h and then without hormonal supplements for an additional 20-22 h. Data was analyzed using statistical analysis system(SAS) program. There was no significant difference in oocyte maturation rate. However, significantly higher (p<0.05) proportions of embryos developed to the blastocyst stage when oocytes were matured in 10% PFF group (45%) than in the 1% PFF group (31.1%). The total cell numbers were not significantly different among groups (52 ± 1.3 vs. 54.6±3.1 vs. 54.4±2.5, respectively). The relative abundance (ratio to beta-actin mRNA) of gene transcripts related to apoptosis in blastocysts was measured by real- time PCR. The expression of anti-apoptotic gene (BclxL) was up-regulated and the expression of pro-apoptotic gene (Bax) was down-regulated in 10% PFF group than in the other groups. Therefore, it can be concluded that supplementation of 10% PFF during in vitro maturation improves embryo development by reduction of apoptosis. * This study was supported by IPET (#311011-05-1-SB010), RNL Bio (#550-20120006), MKE (#10033839-2011-13), Institute for Veterinary Science, the BK21 program and TS Corporation.
        78.
        2012.06 구독 인증기관·개인회원 무료
        Embryo transfer (ET) is the final procedure for getting pregnancy through assisted reproductive technology such as IVF (in vitro fertilization), SCNT (somatic cell nuclear transfer). In our laboratory, the porcine cloned embryos loaded in ET medium are carried for 3 hours by portable incubator because of the great distance from the laboratory to the experimental farm. Thus, before transferring into recipient, porcine cloned embryos are exposed in vitro condition for long time. Medium which is used in this process is the TALP (Tyrode’s medium supplemented with 10 mM HEPES), but it includes little nutrients for embryo. Thus, the aim of this study is to determine whether ET media containing nutrients affect the in vitro development of embryos compared to TALP. For the experiment, porcine zygote medium (PZM)-5 which has amino acids for developing embryo was chosen as ET medium containing nutrients, added 10 mM Hepes as PZM-5 does not contain buffering system. For experiment, we carried out parthenogenesis through a chemical method using Thi/DTT. Parthenogenetic embryos were cultured in PZM-5 for 2 days, and then they were randomly divided into two group; loaded in a straw with TALP or PZM-5-Hepes, respectively. They were stored in a portable incubator for 3 hours to simulate the time consumed in ET, thereafter embryos in both TALP and PZM-5-Hepes groups were respectively cultured in PZM-5 for additional 5 days. All experiments were repeated 5 times. In result, blastocyst formation rate were 22.46%±1.47 and 23.17%± 2.13, respectively and total cell number were 32.9±2.22 and 37.09±2.18, respectively. There is no significant difference between TALP and PZM-5-Hepes groups. * Further study will investigate effect of PZM-5-Hepes on in vivo development of porcine cloned embryo. This study was supported by IPET (#311011-05-1-SB010), RNL Bio (#550-20120006), Institute for Veterinary Science, the BK21 program and TS Corporation.
        79.
        2012.06 구독 인증기관·개인회원 무료
        Adipose tissue-derived mesenchymal stem cells (ASCs) are very interesting in several laboratory animals and humans because they are easy to harvest and expand to generate millions of cells from a small quantity of fat. ASCs are known as useful materials for clinical applications in human cell therapy and as a donor cell in somatic cell nuclear transfer (SCNT). Here, we investigated if 1) minipig ASCs can be isolated, self-renewed and differentiated into multiple tissue lineages, 2) ASCs can be a suitable donor cell type for generation of cloned pig. In order to isolate ASC, adipose tissues were collected from inguinal region of a 6-year-old female minipig. The ASCs were attached to the culture dish with a fibroblast-like morphology. They expressed cell-surface marker characteristics of stem cell, underwent osteogenic, adipogenic, myogenic, neurogenic and chondrogenic differentiation when exposed to specific differentiation-inducing conditions. To investigate its potential as donor cell for cloning, we respectively carried out SCNT using ASC, adult skin fibroblast (ASF) and fetal fibroblast (FF) derived from same minipig. The ratio of blastocysts to 2-cell embryos and total cell number of blastocysts were monitored as experimental parameters. In results, cleavage and developmental competence to blastocysts rate showed no significant difference among the three groups. On the other hand, total cell numbers of blastocysts derived from ASC and FF were significantly higher than in ASF (89±7.9 and 105±5.5 vs. 57.5±5.2, respectively). Our results demonstrated that ASC have potential compared to ASF and FF in terms of the in vitro development and blastocyst formation ability. In further study, we will investigate the in vivo developmental ability of ASC as donor cell for pig cloning. * This study was supported by IPET (#311011-05-1-SB010), RNL Bio (#550-20120006), Institute for Veterinary Science, the BK21 program, TS Corporation and Optifarm Solution.
        80.
        2012.05 구독 인증기관·개인회원 무료
        We analyzed molecular and enzymatic properties of three cholinesterases (ChEs; ClAChE1, ClAChE2 and ClSChE) from Cimex lectularius. The ClAChE1 and ClAChE2 were generally present as a membrane-anchored dimeric insoluble form in the brain and ganglia. In the case of ClSChE, monomeric and dimeric soluble forms were observed. To investigate enzymatic properties, three ChEs were functionally expressed using baculovirus expression system. ClAChE1 revealed a significantly higher activity than ClAChE2 to acetylthiocholine iodide (ATChI) substrate. Kinetic analysis using two choline substrates (ATChI and butyrylthiocholine iodide) demonstrated that ClAChE2 had higher catalytic efficiency but lower substrate specificity than ClAChE1. Inhibition assay was conducted by using three inhibitors (BW284C51, eserine, Iso-OMPA) and two insecticides (chlorpyrifos-methyl and carbaryl). Two ClAChEs revealed high sensitivities to BW284C51, eserine, chlorpyrifos-methyl and carbaryl, but were not sensitive to Iso-OMPA. This inhibition profile confirmed that both ClAChEs are categorized as ChEs. Interestingly, the salivary specific cholinesterase did not show any measurable activities to choline substrates, confirming its non-synaptic function in C. lectularius
        1 2 3 4 5