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        검색결과 166

        141.
        2019.09 KCI 등재 서비스 종료(열람 제한)
        The objective of the current study is to investigate and evaluate the annual and seasonal rainfall trends and patterns of the Punjab province, Pakistan during the 1981-2015. The spatial patterns and temporal trends were identified through the Modified Mann Kendall test. Finding revealed that 13 weather stations of Punjab province have shown the statistically significant decreasing trend of annual and summer monsoon rainfall during the study period. From further investigation, the rainfall during the summer monsoon period (JJAS) found to be increased by 12.45%, similarly the rainfall during the whole of year be also increased by 18.75%. The significant decreasing trends observed with the higher percentage change in annual and monsoon rainfall for the stations of Sialkot and Lahore in the northern and central Punjab. The empirical evidences suggested that northern Punjab gets more moisture as compared the Southern and Western Punjab. This study suggests intensive empirical research in the future to evolve further spatio-temporal trends in the rainfall pattern of Punjab.
        142.
        2017.08 서비스 종료(열람 제한)
        Background & Objectives: Methoxychlor(MET), an organochlorine insecticide, has been thought a potent endocrine disrupting chemical. The present study was undertaken to examine whether short-term exposure to MET can alter the onset of puberty and the associated reproductive parameters such as hormone receptor expressions in prepubertal female rats. Method: MET (1, 10 and 100 mg/kg/day) was administered daily from postnatal day 25 (PND 25) through the PND 34, and the animals were sacrificed on the PND 35. The first V.O. day was monitored, and the weights of reproductive tissues were measured. To assess the structural alterations in the ovary and uterus, the tissues were embedded in paraffin and stained for histological analysis. The transcriptional activities of hypothalamic and pituitary genes were measured using quantitative RT-PCRs. The uterine and hypothalamic proteins were extracted and used for the ER western blotting. Results: As a result, 100 mg group showed advanced V.O. than control, 1 mg group and 10 mg group. The wet weights of ovaries from MET-treated animal dose-dependently increased. The uterine weights were increased in 1 mg group and 10 mg group, while the 100 mg group samples were not significantly different from control tissues. The adrenal, kidney, spleen and thymus weights were not shown any significant change. Corpora lutea and fully grown follicles were observed in the ovaries from the 100 mg group, while numerous primary and secondary follicles were observed in the ovaries from control group. Myometrial thickness of MET-treated group was dose-dependently increased. Epithelial hypertrophy and well-developed glands were observed in the uterus from the 10 mg groups. Conclusions: The present study demonstrated that the short-term exposure to MET during the critical period of prepubertal stage could activate a reproductive endocrine system, resulting the early onset of puberty in immature female rats. Our study suggests that MET’s disrupting effect might be derived from premature activation of key reproduction-related genes in hypothalamus-pituitary neuroendocrine circuit.
        143.
        2017.08 서비스 종료(열람 제한)
        Due to modern trends with postponing child-bearing and getting worse living environment in women, an ovarian aging increased pregnancy failure and other complications with menopause or premature ovarian failure. Although several theories have been suggested such as mitochondrial malfunction, DNA damage/repair/methylation, caloric restriction, studies regarding ovarian aging-related molecular mechanisms for development of therapeutic methods are insufficient so far. Our objective is to determine molecular pathways of ovarian aging that result in pregnancy failure and other complications in women health to develop treatment strategies. This study is consisted of two parts: in Phase I stage, we analyzed distinct gene expression profile between young and aged mouse ovaries, and in Phase II stage several preferentially expressed genes in both ovaries were selected and analyzed their physiological functions and involved molecular networks related to ovarian aging for development of diagnostic markers and therapeutic methods. Ovaries from 10 week and 11 month-old FVB/NJ female mice with synchronized estrus cycle were collected for this study. A half of each ovary was used for RNA preparation and the other half for histological analysis. Using the Illumina HiSeq 2000 System, preferentially expressed genes were identified. Functional annotation database-based gene-set enrichment analyses and Pathway Studio® were employed to evaluate aging-related molecular networks. These findings were confirmed through qRT-PCR and immunohistochemistry. To validate RNA-Seq data, we examined expression patterns of marker genes (Amh, Bmp15 and Nobox) that were wellknown to be decreased in ovarian aging process. In young or aged ovary, preferentially expressed 876 genes were identified and extracellular matrix (ECM; p<0.001) and chromatin/nucleosome-related (p<0.001) protein-coded genes have the majority in these genes by GOTERM analysis. Amongthem, we selected several candidate genes and confirmed their expression profiles by qRT-PCR and immunohistochemistry followed by molecular network analysis. Regarding molecular interactions in these genes, PathwayStudio® was employed to predict aging-involved molecular networks in mouse ovary. Here we report a couple of candidate molecular networks and medicines (chemicals) for targeting these preferentially expressed genes/proteins. Further analyses are scheduled to produce transgenic animal models and with human ovarian tissues/cell lines.
        144.
        2017.06 KCI 등재 서비스 종료(열람 제한)
        Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. In this study, a total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST-SSR markers were developed based on the trials of transferability of these primers in little millet. The EST-SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. The average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. The polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST-SSR markers in assessing genomic relationships in little millet. The findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.
        145.
        2016.12 KCI 등재 서비스 종료(열람 제한)
        Rice blast, caused by a fungus Magnaporthe oryzae, is one of the most devastating diseases of rice worldwide. Analyzing the valuable genetic resources is important in making progress towards blast resistance. Molecular screening of major rice blast resistance (R) genes was determined in 2,509 accessions of rice germplasm from different geographic regions of Asia and Europe using PCR based markers which showed linkage to twelve major blast R genes, Pik-p, Pi39, Pit, Pik-m, Pi-d(t)2, Pii, Pib, Pik, Pita, Pita/Pita-2, Pi5, and Piz-t. Out of 2,509 accessions, only two accessions had maximum nine blast resistance genes followed by eighteen accessions each with eight R genes. The polygenic combination of three genes was possessed by maximum number of accessions (824), while among others 48 accessions possessed seven genes, 119 accessions had six genes, 267 accessions had five genes, 487 accessions had four genes, 646 accessions had two genes, and 98 accessions had single R gene. The Pik-p gene appeared to be omnipresent and was detected in all germplasm. Furthermore, principal component analysis (PCA) indicated that Pita, Pita/Pita-2, Pi-d(t)2, Pib and Pit were the major genes responsible for resistance in the germplasm. The present investigation revealed that a set of 68 elite germplasm accessions would have a competitive edge over the current resistance donors being utilized in the breeding programs. Overall, these results might be useful to identify and incorporate the resistance genes from germplasm into elite cultivars through marker assisted selection in rice breeding.
        146.
        2016.10 서비스 종료(열람 제한)
        Background : Acanthopanax sessiliflorus (Rupr. et Maxim) Seem, belonging to the Araliaceae family, is widely distributed in Korea, China, and Japan. The plants belonging to Acanthopanax species are traditionally used in Korea as anti-rheumatoid arthritis, anti-inflammatory and anti-diabetic drugs and are recognized to have ginseng-like activities. A simple and sensitive high-performance liquid chromatographic (HPLC) method was developed and validated for independent analysis of major compounds and chlorogenic acid in A. sessiliflorus fruits. Chlorogenic acid was reported that prevent cancer and cardiovascular disease in vivo. Also, it has antioxidant effect in vitro test. In the previous experiment, chlorogenic acid were found in A. sessiliflorus fruits. This study was performed to identification of the major compounds and investigate the method validation for the determination of chlorogenic acid in A. sessiliflorus fruits. Methods and Results : Three major compounds were recorded on a Varian Unity Inova AS-400 FT-NMR spectrometer and analyzed by the new HPLC analysis method. HPLC analysis was carried out using an Waters e2695 and PDA detector. The new analyasis method was validated by the measurement of intra-day, inter-day precision, accuracy, limit of detection (LOD, S/N=3), and limit of quantification (LOQ, S/N=10) of chlorogenic acid. The results showed that the correlation coefficient (R2) for the calibration curves of chlorogenic acid was 0.997 in terms of linearity. The limit of detection (LOD) and limit of quantification (LOQ) were 0.565 ㎍/ml and 2.88 ㎍/ml, respectively. There was no interfering peak observed each other and HPLC system was suitable for analysis showing goodness of peak and high precision. Conclusion : This method is suitable to detect and quantify major compounds in A. sessiliflorus fruits. Furthermore, the result will be applied to establish chlorogenic acid as an standard compound for A. sessiliflorus fruits.
        147.
        2016.10 서비스 종료(열람 제한)
        Background : Bitter gourd (Momordica charantia) is a vegetable with pantropical distribution and contains the active ingredient, such as momordicine and charantin. Moreover, bitter gourd has been reported to exhibit antidiabetic, anticancer, cardiovascular-protective and antioxidant effects. But, the distinctive bitter taste of bitter gourd was not suitable for food preference. This study was conducted to evaluate the improvement effects of bitter taste of bitter gourd with natural fermentation and roasting process. Methods and Results : Bitter gourd fruits were obtained from Headeulnyeokae Co., Ltd.(Gang-Jin 59253, Repubilc Korea). Fruits of bitter gourd were prepared by natural fermentation process for 4h at 25℃. After natural fermentation, the fruits were dried in hot-air dryer for 15h at 49-55℃. The dried fruits were roasted in 500 g batches at 120℃ for 10 min in the electric rotisserie oven. After roasting, fruit pieces were extracted with hot water and cold water. One of them was cool-type, and the other was hot-type bitter gourd tea. In the sensory evaluation, hot tea and cold tea showed the high scores on color, flavor and overall acceptability. Conclusion : These mean that roasted bitter gourd had less bitter, and it could be utilized widely as drink and food material.
        148.
        2016.06 KCI 등재 서비스 종료(열람 제한)
        Understanding the genetic variation among landrace collections is important for crop improvement and utilization of valuable genetic resources. The present study was carried out to analyse the genetic diversity and associated population structure of 621 foxtail millet accessions of Korean landraces using 22 EST-SSR markers. A total of 121 alleles were detected from all accessions with an average of 5.5 alleles per microsatellite locus. The average values of gene diversity, polymorphism information content, and expected heterozygosity were 0.518, 0.594, and 0.034, respectively. Following the unweighted neighbor-joining method with arithmetic mean based clustering using binary data of polymorphic markers, the genotypes were grouped into 3 clusters, and population structure analysis also separated into 3 populations. Principal coordinate analysis (PCoA) explained a variation of 13.88% and 10.99% by first and second coordinates, respectively. However, in PCoA analysis, clear population-level clusters could not be found. This pattern of distribution might be the result of gene flow via germplasm exchanges in nearby regions. The results indicate that these Korean landraces of foxtail millet exhibit a moderate level of diversity. This study demonstrated that molecular marker strategies could contribute to a better understanding of the genetic structure in foxtail millet germplasm, and provides potentially useful information for developing conservation and breeding strategies.
        149.
        2015.09 서비스 종료(열람 제한)
        To overcome the risk of the ovarian hyperstimulation syndrome (OHSS) in patients have polycystic ovarian syndrome (PCOS) and to prepare emergency fertility preservation in patients undergoing anticancer treatment, several researchers have reported IVM of oocytes retrieved from ovaries exposed by only hCG priming. However, the maturation rate and the developmental potential of embryos from IVM oocytes are significantly lower than those of oocytes matured in vivo. Here, we investigated the optimal time point for immature oocyte collection at post hCG only injection for in vitro maturation, in vitro fertilization and blastocyst formation. Immature GV oocytes were collected from 25 days old B6D2F1 female mouse at 12 hr, 14 hr, 16 hr or 24 hr post hCG injection. Oocytes were collected from antral or late secondary follicle by puncturing with 26 G needle. Collected oocytes were cultured in G2 medium with 10% FBS, FSH, estradiol, and hCG for 16 hr in vitro and subjected in vitro fertilization and further embryonic development. To examine follicular maturation, we estimated the numbers of primordial, primary, secondary follicle and antral follicle on ovaries of each time point post hCG. To confirm the optimal time point post hCG injection for collecting immature oocytes, we recovered the oocytes from each time point. There is no difference in the number of oocytes per mice. Oocytes collected at 14 hr post hCG injection were shown higher maturation rate to MII stage and blastocyst formation compare to other three groups (p<0.01). However, there is no difference in the maturation rate on the other three groups. Also, apoptotic signal with TUNEL assay or anti-PARP staining was not change in ovaries from all experimental groups. Granulosa cell proliferation test with anti Ki-67 or anti AMH was not show any difference. According to these results, there are no significant differences in four different time points at 12 hr, 14 hr, 16 hr or 24 hr of collection of immature oocytes in hCG primed mouse. However, oocytes from 14 hr post hCG injection showed higher percentages of maturation rate, in vitro fertilization rate, blastocyst formation.
        150.
        2015.09 서비스 종료(열람 제한)
        Cryopreservation has become a powerful method of the assisted reproduction technology and supports fertility preservation of cancer and other indication patients. After controlled ovarian hyperstimulation, surplus oocytes and embryos were recommended to store using cryopreservation. Recently, vitrification is replaced with traditional slow freezing protocol, because of improved survival rates and clinical outcomes. Vitrification requires a high concentration of CPAs that may induce significant osmotic and metabolic damage to cells including oocytes even in a short exposure of a few minutes. Generally, MPF plays a crucial role in the cell cycle regulation and maintaining the meiotic arrest of oocytes. In fact, it has been observed to decline in MII ovine oocytes after vitrification and would be suggested that one of the main causes of low fertilization rate and developmental competence derived from cryoinjury during vitrification. Therefore, the aim of this study was to evaluate the effect of caffeine treatment on the activity of MPF, MAPK level in vitrified/warmed mouse mature eggs. Caffeine, Phosphataseinhibitor, may maintain active form of MPF. We evaluated their survival after warming procedure, fertilization, cleavage, and developmental rates. Ovulated MII eggs were retrieved from 6 weeks old B6D2F1 female mouse at 14hr post hCG injection. Collected MII eggs were maintained in HTF medium containing 10% KSR with or without caffeine for 1hr. Eggs were vitrified in 7.5%EG +7.5%DMSO equilibrium solution, 15%EG + 15%DMSO + 0.5M sucrose vitrification solution with or without caffeine. Also warming solution contained sucrose (0.5M, 0.25M, 0.125M, and 0M) with or without caffeine. After warming, eggs were cultured in HTF medium with or without caffeine for 2 hr then fertilized with epididymal sperm in vitro and cultured in KSOM for 5 days to analyze embryonic development. Survival rates were similar in all experimental groups. However, fertilization rate was higher in with caffeine group compare to without caffeine significantly (80% vs. 85%, p<0.05). 2-cell and blastocyst formation were increased in caffeine group (p<0.05). MPF activity and MAP kinase activity were recovered in with caffeine group after vitrification/warming process. In conclusion, Caffeine may maintain MPF and MAPK level in vitrified/warmed MII eggs, and enhance fertilization and further embryonic development.
        151.
        2015.07 서비스 종료(열람 제한)
        FLOWERING TIME CONTROL PROTEIN, FPA gene encode RNA Recognition Motif (RRM) domain protein and plays important roles in flowering time control in Arabidopsis. Floral transition is significant for reproductive products in all flowering plants. However, little is known about the functions of Medicago autonomous pathway gene. We had cloned the FPA gene on Medicago based on the sequence similarity of Arabidopsis FPA sequence. The RT-qPCR analysis of MtFPA expression patterns showed that the MtFPA transcripts accumulated ubiquitously in roots, leaves, stems, flowers, and pods. When fused to the green fluorescence protein, MtPFA-GFP was localized in the nucleus as speckle pattern of protoplast from Arabidopsis. To examine the function of MtFPA, 35S::MtFPA transgenic plants were generated in Arabidopsis late flowering mutant background, fpa-2. Overexpression of MtFPA specifically caused early flowering under long day conditions compared with non-transgenic plants. In MtFPA transgenic lines, AtFLC expression were down-regulated whereas the floral integrators, AtFT and AtSOC1 were up-regulated as compare with control plant. As these results, MtFPA suggest that is a functional ortholog of the Arabidopsis and may play an important role in the regulation of flowering transition in Medicago.
        152.
        2015.05 서비스 종료(열람 제한)
        Lead leached out from the metal lead-sinker attached to fishing nets or contained in ropes are likely to cause the environmental contamination, consequently, resulting in ecotoxicity. However, it is very difficult to find out the data on the disposal reality of fishing nets, lead-containing form of/in fishing net and its content. In previous studies, we presented the containing form of lead and the lead concentration leached out by the containing forms. As a result, the leaching concentration of lead was the highest under the supposition condition of lead-sinker deposited on sandy tidal flat. In this study, as a subsequent study, we investigated long-term leaching characteristics from lead-sinker deposited on sandy tidal flat. We used a serial batch leaching experiment to investigate the long-term leaching characteristics, and the experimental conditions were as follows; solid to liquid ratio 1:20, shaking time 24 hours (repetition of 7 times), room temperature, and shaking rate 170 rpm. As a result, lead leaching concentration after shaking for 24 hours was 0.215 mg/L, showing the highest leaching concentration, and then the leaching concentrations between 2-7 times were greatly decreased. Analysis result by Visual Minteq 3.1 said most of the leached lead component could be extracted as crystal such as Anglesite (PbSO4), Cerrusite (PbCO3), Cotunnite (PbCl2), and Pb(OH)2 by sulfate and carbonate in seawater.
        153.
        2014.09 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The communications link in a space program is a crucial point for upgrading its performance by handling data between spacecraft bus and payloads, because spacecraft’s missions are related to the data handling mechanism using communications ports such as a controlled area network bus (CAN Bus) and a universal asynchronous receiver and transmitter (UART). The NEXTSat-1 has a lot of communications ports for performing science and technology missions. However, the top level system requirements for the NEXTSat-1 are mass and volume limitations. Normally, the communications for units shall be conducted by using point to point link which require more mass and volume to interconnect. Thus, our approach for the novel communications link in the NEXTSat-1 program is to use CAN and serializer and deserializer low voltage differential signal (SerDesLVDS) to meet the system requirements of mass and volume. The CAN Bus and SerDesLVDS were confirmed by using already defined communications link for our missions in the NEXTSat-1 program and the analysis results were reported in this study in view of data flow and size analysis.
        154.
        2013.07 서비스 종료(열람 제한)
        Legume and rhizobia symbiosis plays an important role in conversion of atmospheric dinitrogen to ammonia. On a global scale, thin interaction represent a key entry point for reduced nitrogen into the biosphere, and as a consequence this symbiosis in important in both natural and agricultural systems. Symbiotic development of nodule organ in triggered by chito-oligosaccharide signals(Nod factors) from the bacterium which are perceived by the legume root. Understanding the molecular and cellular processes that underlie Nod factor perception is one focus of legume biology. Although forward genetics has proved to be an important tool to elucidate key players in Nod factor perception, we still know relatively little regarding the functional networks of genes and proteins that connect the earliest steps of Nod factor perception to immediate downstream outcomes. To identify genes and proteins that link Nod factor perception to cellular and physiological responses we are taking a discovery-based strategy on large-scale transcriptome profiling using RNA sequencing in the roots of Medicago truncatula in response to Sinorhizobium meliloti. Functional characterization of a number of candidate genes is currently in progress to further examine their role in nodulation.
        155.
        2013.06 KCI 등재 서비스 종료(열람 제한)
        This study histologically describes the intersexuality of Scomberomorus niphonius collected from the coastal area near Jeju Island. A total of 126 S. niphonius, collected from March to July 2012 with a total length of 62.4 cm (±17.5) and a total weight of 1,701.9 g (±1,528.9) were used for analyses. From a histological perspective, two types of intersex were confirmed. One type had scattered germ cells from the opposite sex within the gonad. The second type developed germ cells from the opposite sex in the connective tissue of the outer gonadal membrane. The intersexuality was 14.3% (n=18/126), with females (21.3%; n=16/75) exhibiting a higher rate than males (3.9%; n=2/51). There was no displayed correlation between intersexuality and the total length and weight.
        157.
        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.
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