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        검색결과 69

        21.
        2016.06 구독 인증기관 무료, 개인회원 유료
        As a one of unsaturated fatty acid, polyunsaturated fatty acids (PUFAs) have multiple actions: as precursor of prostaglandins (PGs), steroid hormone synthesis and energy production in animal reproduction. PUFAs, which include omega-3 (n-3) and omega-6 (n-6), are derived from the diet and changed by diet, species, breed and season. The plasma membrane of spermatozoa in mammals contain various PUFAs. These composition of PUFAs regulate the membrane fluidity and cause lipid peroxidation via generation of reactive oxygen species (ROS). Induced lipid peroxidation by ROS decreased viability and motility of spermatozoa, and it is reduced by addition of antioxidant and low concentration of PUFAs. Because oocytes of animal have a high lipid components, process of oocyte maturation and embryo development are influenced by PUFAs. In in vitro study, oocyte maturation, embryo development, intracellular cAMP and MAPK activity were increased by treatment of n-3 α-linolenic acid (ALA) during maturation, whereas n-6 linoleic acid (LA) negatively influenced. Also, inhibition of fatty acid metabolism in oocyte influenced blastocyst formation of cattle. PGs are synthesized from PUFAs and various PUFAs influence PGs via regulation of PG-endoperoxide synthase (PTGS). Steroid hormone synthesis from cholesterol is regulated by expression of steroid acute regulator (StAR) protein and mRNA. Exogenous n-3 and n-6 PUFAs altered sex hormone in animal through stimulate or inhibit StAR activity. Because PUFAs altered PG and steroid hormone synthesis, follicular development was influenced by PUFAs. This effect of unsaturated fatty acid could provide information for improvement of reproductive ability in animals.
        4,000원
        22.
        2015.09 구독 인증기관 무료, 개인회원 유료
        Traditionally, Centella asiatica leaf extracts are used to treat neurodegenerative diseases in India. Centella asiatica is reportedly used to enhance memory and treat dementia, but its promoting effect on neural stem cell differentiation has not been studied yet. In the present study, we investigated whether or not Centella asiatica leaf extracts act on neuronal precursor cells and neuronal cell lines to induce neuronal differentiation, neurite outgrowth, and neuroprotection. The neurogenesis-promoting potential of Centella asiatica leaf extracts was determined by differentiation assay on neural stem cells isolated from mouse embryos and PC12 cell lines. To understand the contribution of specific neural cell types towards increase after Centella asiatica treatment, neural stem cells were differentiated into various neural subtypes and checked by Western blotting using neural cell lineage-specific antibody markers. Neuroprotective activity of Centella asiatica was analyzed in PC12 cells exposed to 100 μM of H2O2. Cell growth was analyzed by MTT assay while cell death was analyzed by Western blotting detection of apoptosis-related proteins. Cells treated with Centella asiatica had significantly longer primary and secondary neurites as well as a higher number of neurites per cell compared to control cells. Expression levels of TUBBIII, TH, NF, and BDNF increased upon Centella asiatica treatment, suggesting that Centella asiatica has a neurogenesis-promoting effect. Centella asiatica also inhibited oxidative stress-induced neural cell damage through regulation of apoptosis- and cell cycle-related proteins. Thus, leaf extracts of Centella asiatica might promote neurogenesis, neuroregeneration, and neuroprotection in the context of neurodegenerative diseases.
        4,000원
        23.
        2015.05 구독 인증기관 무료, 개인회원 유료
        The oocyte undergoes various events during maturation and requires many substances for the maturation process. Various intracellular organelles are also involved in maturation of the oocyte. During the process glucose is essential for nuclear and cytoplasmic maturation, and adenosine triphosphate is needed for reorganization of the organelles and cytoskeleton. If mitochondrial function is lost, several developmental defects in meiotic chromosome segregation and maturation cause fertilization failure. The endoplasmic reticulum, a store for Ca2+, releases Ca2+ into the cytoplasm in response to various cellular signaling molecules. This event stimulates secretion of hormones, growth factors and antioxidants in oocyte during maturation. Also, oocyte nuclear maturation is stimulated by growth factors such as epidermal growth factor. This review summarizes roles of organelles with focus on the Golgi apparatus during maturation in oocyte.
        4,000원
        24.
        2014.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Objective of this study was to investigate the effect of nicotinic acid (NA) on the characteristics in fresh semen of miniature pig. We evaluated viability, acrosome reaction and mitochondrial integrity of sperm on 0, 3, 7 and 10 days during storage period with nicotinic acid. As results, the survival rate of sperm in 15 mM NA (day 3, 87.8 ± 1.2%; day 5, 84.0 ± 2.7%; day 7, 82.2 ± 0.9%) and 30 mM NA (day 3, 87.7 ± 0.3%; day 5, 84.4 ± 2.5%; day 7, 82.3 ± 0.7%) groups were higher than control and 5 mM NA groups in 3, 7 and 10 days of semen storage. The NA-treated sperm on 10 day was used day for observing acrosome integrity. The survival sperm with acrosome reaction was higher in 30 mM NA group (day 3, 2.7 ± 0.2%; day 5, 3.3 ± 0.6%; day 7, 11.4 ± 0.3%) than in the control, significantly (P<0.05). Moreover, the live sperm with mitochondrial integrity was higher in whole treatment groups of NA than control group, significantly (P<0.05). Specially, most mitochondrial integrity on 10 day of semen storage was significantly higher in 30 mM NA group (90.2 ± 1.6%) than other treatment groups (control, 81.8 ± 3.1%; 5 mM NA, 83.4 ± 3.0%; 15 mM NA, 89.1 ± 0.7%, P<0.05). In conclusion, supplement of NA in liquid semen of miniature pig can improve and maintain semen quality, such as viability, acrosome reaction, and mitochondria integrity.
        4,000원
        25.
        2014.12 구독 인증기관 무료, 개인회원 유료
        L-Carnitine is an antioxidant for the transport of fatty acids in mitochondria and breakdown of lipids for metabolic energy. Some studies have suggested that carnitine improves sperm motility in mammals. The objective of this study was to investigate the effect of L-carnitine on the characteristics in fresh semen of miniature pigs. The collected fresh semen was stored in modena B medium with L-carnitine (0, 1.0, 2.0, and 4.0 mg/ml) for 10 days at 18℃. The semen quality of viability, acrosome reaction and mitochondria integrity was analyzed on 0, 3, 7, and 10 day of semen storage. The percentages of live and dying sperm were not different among treatment groups with different concentrations of L-carnitine during the storage period. In acrosome reaction analysis, when the sperm stored for 7 day, the percentages of live sperm with acrosome reaction were significantly (p<0.05) lower in 1 (9.0±0.9%), 2 (7.6±0.2%) or 4mg/ml (7.9±0.8%) L-carnitine-treated groups than the control group (0 mg/ml L-carnitine) (11.12±0.2%). However, there were no difference in percentages of live sperm with acrosome reaction for 3 and 10 days of storage with each concentrations of L-carnitine. When sperm was stored for 3 and 10 days, the percentages of live sperm with mitochondria integrity were significantly higher in 2 mg/ml of L-carnitine-treated group than control group (p<0.05). In conclusion, the L-carnitine has a positive effect on acrosome reaction and mitochondria integrity in liquid state of fresh semen in miniature pigs.
        4,000원
        26.
        2012.10 구독 인증기관·개인회원 무료
        Allomyrina dichotoma is a typical pet beetles in Korea. From 2010, similar symptoms of milky spore disease were found collectively in grubs of the species reared in insect farms. They shared a specific symptom that the skin of last instar larvae was changed softer with opaque white and infested grubs eventually died. To clarify the cause of the symptom, we collected the larvae of A. dichotoma from five farms and examined intestinal bacterial florae of them using pyrosequencing technique. From those results, a member of Paenibacillus was found only in the larvae showing the symptom of disease. Through PCR analysis using a Paenibacillus specific primer set, we obtained the partial 16S rRNA gene sequence and confirmed the microbe as Paenibacillus sp. For detailed characterizing, a whole guts was extracted from each larva showing the sign of the disease and incubated at 70℃ for 15 min to isolate spore forming bacteria. After then, each content of guts was cultured on MYPGPNAL agar medium (12.5 μg/ml of nalidixic acid) at 30℃. The 16S rRNA gene sequence analysis for six isolate showed that they were closely related to P. rigui (97.5~98.0% similarity) and to P. chinjuensis (95.9~96.6% similarity). Additional tests including API test and cellular fatty acid composition analysis were performed, but the strain couldn’t be identified at species level, suggesting it may represent novel species of the genus Paenibacillus.
        27.
        2006.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        우라늄 변환시설 가동 중 발생하여 라군(lagoon)에 저장중인 방사성 슬러지 폐기물에 대한 처리는 시설 해체과정에서 매우 중요한 업무 중 하나이다. 슬러지 구성성분 중 다량을 차지하는 질산암모늄의 폭발 위험성 등으로 인해 미생물을 이용한 질산염의 분해는 질산염을 안정적으로 처리할 수 있는 효과적인 방법이라 할 수 있다. 본 연구에서는 라군 슬러지의 약 60 wt%를 차지하는 질산염을 혐기성 균주의 하나인 Pseudomonas halodenidificans를 이용하여 탈질하기위한 공정 변수에 대한 영향을 평가하였다. 온도, 질산염 농도, 전자공여체의 영향, C/N 비율, 초기 접종하는 균주의 비율, pH등의 공정변수에 대하여 실험한 이번 결과는 향후 연속식 공정 설계를 위한 기초 자료로 사용될 것이다.
        4,000원
        28.
        2005.09 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        우라늄 변환시설의 라군 슬러지에 함유된 질산염의 안정적 처리를 위해 물 첨가 용해를 실시한 뒤, 여과 케이크의 안정화 특성에 대하여 알아보았다. 물 용해에 의해 대부분의 질산염은 고농도 질산염 용액으로 제거되었으므로, 여과 케이크의 열분해는 에서 하나의 단계로 수행하였다. Muffle furnace를 이용하여 에서 5시간동안 여과 케이크의 열분해를 실시한 결과 라군 1 슬러지에 포함된 U은 의 열분해와 함께 의 형태로 안정화 되었다. 라군 2 열분해 잔류물의 경우에는 열분해 시 생성된 CaO가 냉각과정에서 수분과 반응하여 로 전환되는 것을 TG/DTA 분석과 XRD 분석을 통해 확인할 수 있었지만, 처분장에서 대기중 노출이나 지하수의 침출 등에는 안정한 화합물로 알려져 있으므로, 특별한 첨가제의 첨가 없이 단순 열분해 후 처분이 가능할 것으로 판단된다.
        4,000원
        29.
        2002.02 KCI 등재 구독 인증기관 무료, 개인회원 유료
        6,100원
        31.
        2020.12 KCI 등재 서비스 종료(열람 제한)
        Hemp (Cannabis sativa L.) is a dioecious plant, although monoecious plants are bred in some cultivars for fiber or seed production. Recently, hemp has received attention for medicinal use with some cannabinoids, including cannabidiol. Self-fertilization for breeding inbred lines is difficult because of dioeciousness and anemophily in hemp. This experiment was conducted to develop a self-fertilization method by forming female flowers and seeds from male plants of dioecious hemp. To induce the formation of female flowers on male plants, 500 ㎎ L-1 of ethephon was sprayed on plants at soon, seven and fourteen days after primordia formation. The plant ratio of female flowers formation and the number of harvested seeds were increased by ethephon treatment. Female flowers of male plants have 5 stigmas in contrast to the dual stigma of female 1plants. Male plant seeds were lighter and smaller than those from female plants. Although the germination rate was lower than that of normal seeds from female plants, the seeds from male plants germinated to grow seedlings. Thus, we suggest that hemp plants should be treated with ethephon at soon after primordia formation to induce the formation of more female flowers on the male plants.
        32.
        2018.06 KCI 등재 서비스 종료(열람 제한)
        In this study, we evaluated the antioxidant activity and protective effects against oxidative DNA damage of the ethyl acetate fraction from the callus of Abeliophyllum distichum Nakai (ECA). Callus of A. distichum was induced on MS medium containing NAA (1 ㎎/L) and 2,4-D (1 ㎎/L), and a sufficient amount was obtained for the extraction by subculture. Acteoside was analyzed and quantified (0.39 ㎎/g callus) from ECA using the high-performance liquid chromatographyphotodiode array detector method. ECA showed very high antioxidative activity as revealed by DPPH and ABTS scavenging assays. The IC50 values were 12.4 and 6.8 ㎍/㎖, respectively. ECA showed protective effects against oxidative DNA damage evaluated by using ψX-174 RF I plasmid DNA. It also inhibited DNA damage by suppressing the oxidative stress-induced protein and mRNA levels of γ-H2AX and p53 in NIH/3T3 cells. In conclusion, ECA protects against oxidative DNA damage through its powerful antioxidant activity.
        33.
        2017.05 서비스 종료(열람 제한)
        Backgoound : This study was conducted to evaluate the quality variation of Ixeris dentata on the antioxidant contents and antioxidant activities according to the different producing area. Methods and Results : The samples were extracted with 70 % EtOH and then analyzed for total flavonoid contents, polypenol contents, DPPH radical scavenging activity, and ABTS radical scavenging activity. Luteinol 7-O-β-D-glucoside, an index component of the Ixeris dentata, was analyzed by HPLC. The leafs of Ixeris dentata in Jinan had the highest concentration of polyphenols (23.91 ㎎/g), followed by Jinbu (22.63 ㎎/g) and Eumseong (21.36 ㎎/g). Flavonoid content was highest in Jinan (15.27 ㎎/g), but there was no significant difference between Jinbu (14.05 ㎎/g) and Eumseong (13.99 ㎎/g). The contents of luteinol 7-O-β-D-glucoside were confirmed in Jinan (0.68%), Jinbu (0.49%) and Eumseong (0.36%), respectively. Conclusion : The comparison of antioxidant contents and antioxidant activities of Ixeris dentata according to the different producing area, Jinan was had the highest concentration, followed by Jinbu and Eumseong. Our results showed that the content of luteoline-7-D-glucoside varied among the different producing area.
        34.
        2015.07 서비스 종료(열람 제한)
        We recently reported rice promoters that are active in late stages of pollen development. However, rice promoters that allow manipulation of gene expression at earlier stages of pollen development are still very limited to date. In this study, we have chosen 10 putative microspore promoters, OsMSP1 through OsMSP10, based on publicly available transcriptomic datasets in rice (Oryza sativa L.). Sequence analysis of these promoter regions revealed some cis regulatory elements involved in pollen-specific expression. We also examined promoter activities using the promoter-GUS reporter constructs in both transgenic rice and Arabidopsis. In rice, all of the 10 promoters directed GUS signals from the microspore stage throughout the all stages of pollen development. In addition, while GUS signals from 4 promoters, OsMSP2, OsMSP7, OsMSP9 and OsMSP10, seem to be expressed preferentially during pollen development, those from other six promoters were observed in vegetative tissues such as leaves, stems, and roots of seedlings. Similarly, in Arabidopsis, all of the 10 promoters directed GUS signals during pollen development. In detail, 8 promoters, OsMSP1 ~ OsMSP8 directed GUS signals from the microspore stage, whereas 2 promoters, OsMSP9 and OsMSP10, exhibited GUS signals from tricellular stage. Furthermore, seven promoters, except for OsMSP1, OsMSP2 and OsMSP10, showed GUS signals in shoot apical region or root tissues of seedlings. Furthermore, we verified microspore activity of four promoters, OsMSP1, OsMSP2, OsMSP3 and OsMSP6, by complementation analysis of the sidecar pollen (scp) mutant which displays microspore-specific defects. Currently, further analyses are underway for GUS expression of T2 generation in transgenic rice and scp complementation with remaining promoters.
        35.
        2015.07 서비스 종료(열람 제한)
        Tissue-specific promoters are a very useful tool for manipulating gene expression in a target tissue or organ; however, their range of applications in other plant species has not been determined, to date. In this study, we identified two late pollen-specific rice promoters (ProOsLPS10 and ProOsLPS11) via meta-anatomical expression analysis. We then investigated the expression of both promoters in transgenic rice (a homologous system) and Arabidopsis (a heterologous system) using ProOsLPS10 or ProOsLPS11::GFP-GUS constructs. As predicted by microarray data, both promoters triggered strong GUS expression during the late stages of pollen development in rice, with no GUS signals detected in the examined microspores and sporophytic tissues. Interestingly, these promoters exhibited different GUS expression patterns in Arabidopsis. While in Arabidopsis, the OsLPS10 promoter conferred GUS expression at the uni- and bi-cellular macrospore stages, as well as at the shoot apical region during the seedling stage, the OsLPS11 promoter was not active in the pollen at any stage, or in the examined sporophytic tissues. Furthermore, by performing a complementation analysis using a sidecar pollen (scp) mutant that displays developmental defects at the microspore stage, we found evidence that OsLPS10, which can be an applied promoter expressed in Arabidopsis, is useful for directing gene expression in the early stages of pollen development. Our results indicate that the OsLPS10 and OsLPS11 promoters can drive the expression of target genes during the late stages of pollen development in rice, but not in Arabidopsis. Our results also emphasize the necessity of confirming the applicability of an established promoter to heterologous systems.
        36.
        2014.07 서비스 종료(열람 제한)
        OsLPS is pollen specific gene that express at late stage of pollen development in rice. Based on microarray database, promoter region of two genes Os03g0106900 and Os03g0106500 were identified. The sequence of 2287bp and 2468bp upstream region of these genes were amplified and designated as OsLPS10 and OsLPS11. These promoters were fused with GUS-GFP reporter gene in a destination vector, pKGWFS7 and introduced into rice (Dongjin cultivar) and Arabidopsis (Col-0). The results of GUS assay showed different pattern of gene expression in pollen of rice and Arabidopsis. In Arabidopsis, the OsLPS10 gene strongly activated in young anther and not expressed in mature pollen. Pollen development analysis revealed GUS expression was detected at unicellular stage and strongest at the bicellular pollen developmental stage. No GUS signal was recorded in mature pollen. In case of OsLPS11, no GUS signal was detected in during pollen development of inflorescent. By contrast, in rice, the GUS expression pattern of OsLPS10 and OsLPS11 exhibited similar. GUS expression was first detectable in the anthers of spikelets at the bicellular stage and intensity increased in tricellular and mature pollen. The GUS signal was not detected in the anthers in unicellular microspores in both genes, OsLPS10 and OsLPS11. The results suggested that these genes were different activity in heterologous plant system, monocot and dicot. Complementation analysis and Cis-regulatory elements will be examined to illuminate the characteristic of these genes
        37.
        2014.07 서비스 종료(열람 제한)
        Based on the results of microarray analysis we selected ten candidate genes that express in pollen at the early pollen developmental stage. By PCR amplification, the promoter region of these genes were amplified from rice genomic DNA (Nipponbare) and cloned into the destination pKGWFS7 vector via an entry vector, pDONR201. The characteristic of promoters were evaluated in Arabidopsis thaliana (Col-0) through GUS expression analysis. Fifty T2 plants respectively from each promoter were tested. Whole inflorescence of individual plant was stained with 1mM X-Gluc solution to observe tissue-specific GUS expression patterns. The results showed that all 10 promoters activated in pollen tissues. Among them six promoters expressed at the early developmental stage (unicellular) of pollen and the others expressed at both early (unicellular) and late pollen developmental stage (mature pollen). The results indicated that these promoters would be potential applicable for the studies of pollen function. Currently, we are performing these promoters analysis in rice transgenic plants as well as molecular characterization.
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