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        검색결과 9,514

        8041.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The objective of this study was to analyze the genetic diversity using SSR marker and investigate the fatty acid composition of perilla (P. frutescens var. frutescens) germplasm. Genetic diversity among 95 accessions, which consisted of 29 weedy types and 66 landrace accessions, was evaluated based on 12 SSR markers carrying 91 alleles. The mean values of observed (HO) and expected heterozygosities (HE) were 0.574 and 0.640, respectively, indicating a considerable amount of polymorphism within this collection. A genetic distance-based phylogeny grouped into two distinct groups, which were the landrace, moderate and weedy type, genetic distance (GD) value was 0.609. The physicochemical traits about crude oil contents and fatty acid compositions were analyzed using GC. Among tested germplasm, the total average oil contents (%) showed a range from 28.57 to 49.67 %. Five fatty acids and their contents in the crude oils are as follows: α-linolenic acid (41.12%-51.81%), linoleic acid (15.38%-16.43%), oleic acid (18.93%-27.28%), stearic acid (2.56%-4.01%), and palmitic acid (7.38%-10.77%). The average oil content of wild types was lower than landrace, and the oil content of middle genotype accessions was higher than other germplasm, but no significant variation between landrace and wild types was shown. Nevertheless, IT117174, landrace of Korea, was highest in crude oil content (47.11%) and linolenic acid composition (64.58%) among the used germplasm. These traits of the selected accessions will be helped for new functional plant breeding in perilla crop.
        8042.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        Sea Buckthorn (Hippophae rhamnoides L.) has been used in traditional medicine for the treatment of cough, indigestion, circulatory problems and pain. The associated anti-inflammatory effect of this agent is achieved via the inhibition of Nf-kB signaling, a property that has been demonstrated to effectively control the symptoms of various skin disorders, including atopic dermatitis. Accordingly, the purpose of this study was to assess the efficacy of Sea Buckthorn in reducing the production of lipopolysaccharide (LPS) activated nitric oxide (NO) by inhibiting the Nf-kB pathway, as measured by the symptoms of atopic dermatitis (AD) occurring secondarily to inflammation and immune dysregulation. Our data demonstrate that Sea Buckthorn significantly decreased the LPS-induced production of NO (p〈0.001). Atopic dermatitis was induced by repeated application of 2,4-dinitrochlorobenzene to the dorsal skin of mice. Topical application of 5% Sea Buckthorn extract improved the symptoms of AD, specifically reducing disease severity scores, scratching behaviors and epidermal thickness. When compared to the control group, animals treated with Sea Buckthorn exhibited increased serum IL-12 levels and decreased serum TNF-α, IL-4 and IL-5 levels. Such a modulation of biphasic T-helper (Th)1/Th2 cytokines may result in a reduction in serum IgE levels. Our findings suggest that mechanism of action of Sea Buckthorn in the treatment of AD is associated with a marked anti-inflammatory effect as well as an inhibition of Th2-mediated IgE overproduction via the modulation of biphasic Th1/Th2 cytokines. Such results suggest that topical Sea Buckthorn extract may prove to be a novel therapy for AD symptoms with few side effects.
        8043.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        Herb extracts commercially used in Korea were screened for PPAR-γ agonist test and α-glucosidase inhibition assay. Total 16 herb plants had a PPAR-γ agonist activity. Specially, Alisma orientale Juz (108.41%), Ephedra sinica (98.22%), Sasa japonica Makino var. purpurascens Nakai (140.68%), Astragalus membranaceus Bunge (106.79%) and Cnidium officinale Makino (113.00%) showed high PPAR-γ agonist activity rate compared with rosiglitazone's (167.46%). And Cornus officinalis S. et Z. (90.3%), Cinnamomum cassia Blume (89.2%), Psoralea corylifolia L. (89.8%), Paeonia japonica (Makino) Miyabe (92.4%) and Paeonia suffruticosa Andr (93.2%), showed high α-glucosidase inhibition rates. These results support previous reports of the efficacy of Oriental medicinal plants used for diabetes mellitus.
        8044.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The mushroom Coriolusversicolor contains biologically active polysaccharides, most of which belong to the β glucan group. Diverse physicochemical properties, due to different sources and isolated types of β-glucans, may induce distinct biological activities. Here, we examined the effects of β-glucan from Coriolusversicolor (CVG) on the scavenger receptor B1 (SR-B1) expression and the role of SR-B1 in CVG-induced phagocytosis regulation by using SR-B1-specific shRNA transfected cells. We also examined whether Dectin-1 and CK2 are involved in SR-B1 expression in CVG-treated cells. Our study results showed that CVG increased the SR-B1 expression via Dectin-1 and CK2 in macrophages. However, the inhibition of SR-B1 expression by shRNA did not completely eliminate the effect of CVG on the increase of phagocytosis suggesting that SR-B1 is not essential for CVG-stimulated phagocytosis. This study will contribute to identify CVG's mechanism of action and its use in the development of functional foods.
        8045.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        Muscle strength and endurance activities of Korean ginseng (Panax ginseng C. A. Meyer; KG) were compared with those of wild simulated cultivation ginseng (WCG) in mice. Fifty male ICR mice were divided into five groups: A (vehicle); B (WCG 100 mg/kg); C (WCG 500 mg/kg); D (KG 100 mg/kg); E (KG 500 mg/kg). Subsequently, the mice were subjected to the forced swimming test (FST) and treadmill test at the 4th and 7th weeks. The glycogen content in the muscle and blood analysis (levels of glucose, triglyceride (TG), IGF-1) were also performed immediately after the last FST and treadmill test at the 7th week. Immobility times in FST were shorter in WCG- than KG-treated groups, and the results of the treadmill tests were also significant except for KG-treated at 100 mg/kg. The glycogen content was increased in both groups with a peak at 500 mg/kg of WCG groups. Serum concentrations of TG and glucose were decreased by administration of KG and WCG and all treated groups showed increase in the level of IGF-1 in serum. These results suggest that KG and WCG supplementations are effective in escalating the muscle strength and endurance.
        8046.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Astronomical Observations at Chungbuk National University Observatory (CBNUO) with an 1 m telescope have begun since April 2008, and Near-Earth Space Survey observations also have been started since November 2010, with a 0.6 m wide field telescope developed by Korea Astronomy and Space Science Institute. To improve observational efficiency, we developed a weather monitoring system enabling automatic monitoring for the weather conditions and checking the status of the observational circumstances, such as dome status. We hope this weather monitoring system can be helpful to more than 100 Korean domestic observatories, including public outreach facilities. In this paper, we present the statistic analysis of the weather conditions collected at CBNUO for 3 years (2009- 2011) and comparisons were made for clear nights between using only humidity data and both humidity and cloud data.
        8047.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        It is a crucial matter to select a landing site for landers or rovers in planning the Mars exploration. The landing site must have not only a scientific value as a landing site, but also geographical features to lead a safe landing for Mars probes. In this regard, this study analyzed landing site of Mars probes and rovers in previous studies and discussed the adequacy of the landing site to scientific missions. Moreover, this study also examined domestic studies on the Mars. The frameworks of these studies will guide the selection of exploration sites and a landing site when sending Mars probe to the Mars through our own efforts. Additionally, this paper will be used as the preliminary data for selection of exploration site and a landing site.
        8048.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The solar proton telescope (SPT) is considered as one of the scientific instruments to be installed in instruments for the study of space storm (ISSS) which is determined for next generation small satellite-1 (NEXTSat-1). The SPT is the instrument that acquires the information on energetic particles, especially the energy and flux of proton, according to the solar activity in the space radiation environment. We performed the simulation to determine the specification of the SPT using geometry and tracking 4 (GEANT4). The simulation was performed in the range of 0.6-1,000 MeV considering that the proton, which is to be detected, corresponds to the high energy region according to the solar activity in the space radiation environment. By using aluminum as a blocking material and adjusting the energy detection range, we determined total 7 channels (0.6~5, 5~10, 10~20, 20~35, 35~52, 52~72, and >72 MeV) for the energy range of SPT. In the SPT, the proton energy was distinguished using linear energy transfer to compare with or discriminate from relativistic electron for the channels P1-P3 which are the range of less than 20 MeV, and above those channels, the energy was determined on the basis of whether silicon semiconductor detector (SSD) signal can pass or not. To determine the optimal channel, we performed the conceptual design of payload which uses the SSD. The designed SPT will improve the understanding on the capture and decline of solar energetic particles at the radiation belt by measuring the energetic proton.
        8049.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        In this study, the transient second or third layer on the topside of the Martian ionosphere were investigated with the most recently released Mars advanced radar for subsurface and ionospheric sounding/Mars Express data obtained from January 2010 to September 2011 to study the correlation between these topside additional layers and surface magnetic fields, solar zenith angle and solar activities. When examining the zones where the topside layer appeared, the occurrence rate of the topside layer was low at the areas with a strong Martian crustal magnetic field as observed by the Mars global surveyor. The occurrence rate of additional layers on the Martian topside ionosphere decreases as the solar zenith angle increases. However, these layers appeared significantly near the terminator of which solar zenith angle is 90°. In comparison between F10.7 which is the index of solar activities and the occurrence rate of the topside layer by date, its occurrence rate was higher in 2011 than in 2010 with less solar activities. The result of this study will contribute to better understanding of the environments in the topside of the ionosphere through the correlation between the various conditions regarding the Martian ionosphere and the transient layer.
        8050.
        2012.11 서비스 종료(열람 제한)
        Since cable members are the major structural components in cable bridges, they should be properly inspected for surface damage as well as inside defects such as corrosion and/or breakage of wires. In this study, only the vision-based surface damage detection system based on image processing techniques is addressed. The damage detection programs are consist of real-time and post processing detection programs. The proposed damage detection programs were verified through laboratory tests on many types of cables.
        8051.
        2012.11 서비스 종료(열람 제한)
        This paper presents a mathematical model on the longitudinal mid-span extension of the Tamar Bridge, UK by using 6 months data of temperatures and an extension starting from July 2010. Linear models of temperature input-extension output were identified for all the combinations of input temperatures. The model using two temperatures, one temperature on the top of the mid-span section and the other on the bottom, was found to be the best with the fitness value 95.9% while single-temperature input models had maximum fitness 80%. This observation might be explained by the temperature gradient at the section: in the existence of the temperature gradient, two temperatures in the section may represent the temperature distribution of the section well while a single temperature can't. A further study needs to be carried out to verify it by a thermal simulation on a Finite Element model of the bridge.
        8052.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        This study was carried out to investigate the characteristics of disinfection by-products (DBPs-trihalomethanes (THMs), haloacetic acids (HAAs) and haloacetonitriles (HANs) formation in chlorination of principal raw waters used for drinking water on Jeju Island, Korea. The domestic water supply of other area and humic acid solution (HA) were used as a reference point. The effects of chlorine contact time, solution temperature and pH on DBPs formation potential (DBPFP) were investigated for raw waters. In addition, the effect of Br- was studied for HA. The DBPFP (THMFP, HAAFP and HANFP) were increased with increasing chlorine contact time. Comparing the individual DBPFPs for raw waters, they decreased in the order of HAAFP > THMFP ≥ HANFP. As the solution temperature was increased, the THMFP, HAAFP and HANFP increased. With increasing the solution pH, the THMFP was increased, but HAAFP and HANFP were decreased. With the addition of 0.3 mg/L Br- for HA, the DBPFP was increased and the major chemical species changed: from trichloromethane to dibromochloromethane and tribromomethane for THMs; from dichloroacetic acid and trichloroacetic acid to tribromoacetic acid for HAAs; and from dichloroacetonitrile to dibromoacetonitrile for HANs.
        8053.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        Effects of pretreatment and extraction conditions on total polyphenol yield from licorice root were investigated using statistical method. For pretreatment, heat treatment at 121°C for 10 min was applied. Licorice root content in solvent (10, 20, and 30%) ethanol concentration (20, 40, and 60%) and reaction time (1, 2, and 3 h) were used as variables for extraction conditions. Two experiments, with heat treated and no treated licorice, were prepared with same experimental design. Box behnken design was employed and produced a total of 15 trials. Total polyphenol yield from licorice root was not affected by heat treatment. Among variables, licorice content in solvent showed most significant effect regardless of other variables (p
        8054.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        남극 지의류인 Ramalina terebrata에서 분리 정제된 라말린(γ-glutamyl-N'-(2-hydroxyphenyl)hydrazide)은 이전 연구에서 강력한 항산화능을 확인하였다. 본 연구에서는 라말린의 추가적인 효능을 확인하기 위하여, 비암세포 세포주인 멜란에이 세포를 이용하여 라말린의 멜라닌 합성에 대한 효과를 확인하였다. 라말린은 세포 독성이 없는 농도에서, 멜란에이 세포에서 멜라닌 합성을 농도 의존적으로 감소시켰으며, 이러한 효과는 널리 사용되고 있는 미백제인 알부틴보다 우수하였다. 라말린은 무세포 타이로시네이즈의 활성을 직접 저해했을 뿐만 아니라, 세포 내의 타이로시네이즈의 활성도 저해하는 효과를 보였다. 라말린의 이러한 멜라닌 합성 저해의 기전 연구를 위하여, 멜라닌 합성에 중요한 단백질인 타이로시네이즈, TRP-1, TRP-2의 mRNA와 단백질 발현을 조사한 결과, mRNA양에는 영향을 주지 않고,단백질의 발현은 감소되는 것으로 나타났다. 또한, 0.2 % 라말린을 포함한 제형을 사람피부에 도포하였을 때, 3주 후에 피부 밝기가 개선됨을 확인하였다. 이상의 결과를 통해서, 라말린은 타이로시네이즈의 직접적인 저해뿐만 아니라 멜라닌 합성과 관련된 단백질의 발현을 저해함으로써 미백효과를 나타낸다고 할 수 있으며, 이러한 효과를 인체시험을 통해 확인하였다. 따라서, 라말린은 멜라닌 합성을 저해하는 미백 소재로 활용될 수 있을 것으로 판단된다.
        8055.
        2012.09 KCI 등재 서비스 종료(열람 제한)
        Through the sampling four rice cultivars with differing amylose contents, the relationship between the structural and gelatinization properties of endosperm starches was analyzed. These rice varieties exhibited different chain length distribution ratio within the amylopectin cluster as well as varing amylose levels. The proportion of amylopectin short chains of in Goami cutlivars was higher than the other varieties, whereas the Goami 2 which shows amylose extender mutant properties in the endosperm showed the highest proportion of long chains. In X-ray diffraction analysis of rice starches, the Goami 2 variety displayed a B-type pattern whereas the other varieties were all A-type. Among the cultivars with high and normal rice starch levels, those with the higher amylose contents showed distinctly lower swelling. Goami 2 rice was found to have the highest onset and peak gelatinization temperature from the differential scanning calorimetry results. The four rice cultivars under analysis also showed different rates of hydrolysis by amyloglucosidase. These findings suggest that the composition and chemical structure of the starch content is a major determinant of both the gelatinization and functional properties of rice.
        8056.
        2012.09 서비스 종료(열람 제한)
        We examined the morphometric characteristics and fluctuating asymmetry of diploid and triploid marine medaka, Oryzias dancena. We used morphometric parameters the truss and classical dimensions. Significant differences in all the classical and truss dimensions of the diploid and triploid fish. All the dimensions of the triploid fish were greater than those of the diploid fish. The triploid marine medaka shows sexual dimorphism in these characters, and the sexual dimorphism of the triploid marine medaka is similar to that of the diploid marine medaka. Thus, the growth of triploid marine medaka is faster than that of the diploid fish, and it displays clear sexual dimorphism, with male fish having longer dorsal and anal fins than female fish. we examined fluctuating asymmetry of eye diameter, maxilla length, operculum length, number of pectoral fin ray and number of pelvic fin ray. In all experimental groups, Eye diameter and maxilla length showed no significant difference between left side and right side (P>0.05). Trends of operculum length in triploid male group and pectoral fin ray's number in diploid male group showed similar trend with trends of operculum length in triploid female group and pectoral fin ray’s number in diploid female group. However, trends of operculum length in diploid male group and pectoral fin ray's number in triploid male group showed opposite trend with trends of operculum length in diploid female group and pectoral fin ray’s number in triploid female group. Trend of pelvic fin ray's number in all groups showed similar trend with trend of pectoral fin ray’s number in all groups.
        8057.
        2012.09 서비스 종료(열람 제한)
        Aquaporin 5 (AQP5) implicated in the generation of saliva, tears, and pulmonary secretions functions as a water-specific channel. Epididymal epithelial cells actively reabsorb water, ions and proteins. Large quantity of testicular fluid movement across the epididymal tubules generates high osmotic milieu which is important for sperm maturation. In an effort to understand the fluid homeostasis and its regulation by sex steroids in male reproductive tract, the expression of AQP5 was examined in different regions of mouse epididymis during postnatal development. The effect of androgen on the expression of epididymal AQP5 was examined in ORX model. AQP5 mRNA levels were the highest in corpus region in which drastic increase was noted during sexual maturation. Epididymal AQP5 immunoreactivity was largely found in apical as well as basal region of luminal epithelia. Moderate immunoreactivity for AQP5 was found in in smooth muscle cells in both immature and mature mice. Epididymal lumen of ORX mice showed shrinkage together with decrease in AQP5 expression. Alteration of AQP5 expression in ORX epididymis was partially recovered by androgen injection. AQP5 mRNA was induced at 10uM 5α-DHT in organ cultured epididymis. Chromatin immunoprecipitatin (ChIP) showed that 5α-DHT induced recruitment of androgen receptor (AR) to the -4635 to -4453 bp region of the AQP5 gene promoter in adult epididymis. Taken together, axial regulatory mechanism may control transcription of AQP5 along the length of epididymal tubule. Water transport through AQP5 is important for late sperm maturation and storage in epididymis. Androgen may directly induce AQP5 gene transcription via activation of AR in epididymis.
        8058.
        2012.09 서비스 종료(열람 제한)
        Glycan epitopes of cellular glycoconjugates act as versatile biochemical signals, and this sugar coding plays an important role in cell-to-cell recognition processes. In the present study, our aims were to determine the distribution of sperm receptors with activity for fucosyl- and galactosyl glycans and to address whether mono sugar neoglycoproteins functionally mimic the binding between zona pellucida (ZP) glycoproteins and sperm. In mouse epididymal spermatozoa with intact acrosomes, fucopyranosyl bovine serum albumin (BSA-Fuc) bound to the segment of the acrosome, the equatorial segment, and the postacrosome region of the sperm head. Galactosyl BSA (BSA-Gal) binding activity was similar to that of BSA-Fuc, but was weaker. In acrosome-reacted spermatozoa treated with the Ca2+ ionophore A23187, BSA-Fuc binding was lost in the apical segment of the acrosome but remained in the equatorial segment and postacrosome regions. BSA-Gal binding to the equatorial region was increased. In the presence of 2.5 μg/ml BSA-Fuc, in vitro sperm - ZP binding was significantly decreased, indicating that fucosyl-BSA functionally mimics ZP glycoproteins during sperm-egg ZP interactions. At the same concentration, BSA-Gal was not effective. Fucosyl BSA which efficiently inhibited the sperm-ZP binding can mimic the ZP glycoconjugate and has potential for use as a sperm fertility control agent in mouse.
        8059.
        2012.09 서비스 종료(열람 제한)
        Human embryonic stem cells (hESCs) are promising cell source because of their unique self-renewal and pluripotency. Although hESC-derived cardiac cells are currently generated worldwide, cryopreservation of these cells is still limited due to low rate of post-thaw survival. Cryopreservation of hESC-derived cardiac cells is critical in that their long-term storage can accelerate their use in regenerative medicine. However, to date, there are few reports on efficient cryopreservation and post-thaw survival of hESC-derived cardiac cells. In this study, we evaluated the effects of ginsenoside, which is known to improve survival of rat embryonic cardiomyocytes against myocardial ischemia injury in diabetic rats (Wu et al., 2011), on the survival of hESC-derived cardiac cells after thawing. We induced differentiation into cardiac cells using our previously reported method (Kim et al., 2011). Differentiated, pre-beating stage cardiac cells were cryopreserved using either mass cryopreservation or vitrification. To evaluate the effects of ginsenoside (Re, Rb), we compared three sets: pre- and post-thaw treatment, pre- or post-thaw treatment only. The survival of post-thaw cardiac cells were evaluated using Trypan-blue and Annexin V staining. In addition, the three groups were treated with ROCK inhibitor Y-27632, and compared with non-treatment groups. The effect of ginsenoside was significant in post-thaw treatment group, i.e, thawed cells expressed cardiac specific genes and showed specific functionality such as spontaneous beating. Taken together, we demonstrated favorable effects of ginsenoside on the survival of hESC-derived cardiac cells after cryopreservation and thawing. These results suggest a possible application of well-known cardioprotectant ginsenoside in cell-based tissue engineering using hESC-derived cardiac cells.