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        검색결과 199

        81.
        2011.03 구독 인증기관 무료, 개인회원 유료
        Neurotoxicity and oxidative injury induced by glutamate cause neuronal degeneration related to various central nervous system diseases. Resveratrol, a polyphenolic compound, is known to have antioxidative and anti-inflammatory effects. The aim of this study was to investigate the question of whether resveratrol has a neuroprotective effect against glutamate-induced toxicity in cultured cortical neurons. Following exposure to glutamate for 15 min, cortical neurons originating from ICR mouse fetuses on embryonic days 15-16 were then treated with resveratrol for 24 h in the post-treatment paradigm. Glutamate induced a significant reduction in cell viability; however, resveratrol induced a significant increase in cell viability. Glutamate induced generation of ROS and apoptotic neuronal death; however, these were decreased by exposure to resveratrol. mRNA expression in antioxidant enzymes, cytoplasmic glutathione peroxidase, copper/zinc superoxide dismutase (SOD), and manganese SOD, and anti-apoptotic regulator Bcl-xL were decreased by exposure to glutamate, however, exposure to resveratrol resulted in a significant increase in their mRNA levels. In addition, mRNA expression of pro-inflammatory cytokines, interleukin-1β and tumor necosis factor-α, was increased by glutamate insult, but significantly reduced by resveratrol. These findings indicate that resveratrol is neuroprotective against glutamate-induced toxicity, suggesting a useful therapeutic application in treatment of neurodegenerative disorders.
        4,200원
        82.
        2010.12 구독 인증기관 무료, 개인회원 유료
        Phospholipid hydroperoxide glutathione peroxidase (PHGPx) is a unique antioxidant enzyme involved in reduction of peroxidized phospholipids within biomembranes. To investigate the expression pattern of the PHGPx gene during fetal development, in situ hybridization analyses were performed using mouse FITC-labeled PHGPx cRNA probes in fetal tissues on embryonic days (Ed) 13.5-18.5. During these periods, PHGPx mRNA appeared in the developing telencephalon, diencephalon, spinal cord, and spinal ganglion. In particular, PHGPx mRNA was strongly expressed in pyramidal cells of the cerebral cortex. On Eds 17.5-18.5, PHGPx mRNA was detected in various tissues including liver, intestinal villi and crypt, pancreas, lung, and olfactory epithelium of the nasal cavity. In addition, PHGPx mRNA was highly expressed in the inner ear on Eds 14.5-18.5, brown fat on Ed 17.5, and adrenal gland on Ed 18.5. It is conceivable that PHGPx may act as an important antioxidant against fetal oxidative stress during mouse organogenesis.
        4,000원
        84.
        2010.09 구독 인증기관 무료, 개인회원 유료
        Animal crude drugs (natural medicines derived from animal organs) have been widely used in various Chinese medicine for the therapeutic effects and for enhancement of immunologic functions. We found the specific identification methods using DNA sequencing and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analyses for mitochondrial DNA (mt DNA) in order to discriminate between the animal species and organs as well as the placenta of humans. Species-specific PCR bands of D-loop mt DNA for equine, bovine, porcine, and human were 133 bp, 137 bp, 231 bp, and 240 bp, respectively. Porcine organs were identified using restriction enzyme, HphI cut into two subfragments, 36 bp and 195 bp bands in the heart, spleen, and liver, except for kidney. The heart and liver of porcine were identified using restriction enzyme, SpeI cut into two subfragments, 84 bp and 147 bp bands, except for kidney and spleen. Bovine organs were cut into 68 bp and 69 bp bands in the liver, kidney, and spleen using NalIV, except heart and placenta. Placentas of bovine and humans were easily identified using each primer. Our results suggest that sequencing of mt DNA and its PCR-RFLP methods are useful for identification and discrimination of inter- and intra-specific variations in equine, bovine, porcine, and human by routine analysis.
        4,000원
        85.
        2009.12 구독 인증기관 무료, 개인회원 유료
        This study was to investigate pregnancy rate of IVM/IVF/IVC Korean cattle (registered in government) embryos according to transport time course. For the production of embryos, oocytes recovered from slaughtered excellent grade cow and highly motile frozen‐thawed bull semen (purchased from LIMC, KPN#497) was used. In vitro produced embryos were cultured in CR1aa medium for 8 days and some of them were frozen. The rate of average cleavage (>2‐cell) was 83.0% (308/371) and blastocyst rate at day 8 was 34.7% (107/308). Among in vitro produced blastocyst embryos at day 8, most healthy embryos were freshly transferred on production day and some frozen embryos were direct transferred on appropriate day. These embryos were produced in a laboratory, embryo transfer (ET) was planned in 10 areas of the remote island (Jeju) from the laboratory by airplane. Thus, we examined the pregnancy rate in recipient cow according to embryo of transport time course before ET. From embryo transferred 44 recipient cows, overall pregnancy was 40.9% (18/44), these 18 cows were all calved [single, 94% (17/18); twin, 6% (1/18)] and total embryo implantation rate was 26% (19/66). Comparing transport time in the base of 6 hr, pregnancy rate in ET group required less 4 hr (60%, 9/15) was significantly higher than that required more 6 hr (26.3%, 5/19). In direct ET of freezing embryos, the pregnancy rate was 40% (4/10). However, it was difficult to find the meaning of temperature, pH and corpus luteum quality of recipients on comparison of pregnancy rate. When the cell death level of embryos according to storage time in thermos (straw container) before ET was measured by TUNEL staining, apoptotic index was increased with storage time‐dependent. These results demonstrated that long distance transfer of IVM/IVF/IVC embryos is possible and the time of embryo transport is very important for the pregnancy rate on field trial.
        4,000원
        86.
        2009.10 구독 인증기관·개인회원 무료
        We report for the first time the occurrence of DWV-infected bumble bees (Bombus ignitus). For the present study, the detection of DWV virus from the female and male bumble bee was investigated in the same colony. The Deformed wing virus (DWV) of honeybee (Apis mellifera) is closely associated with characteristic wing deformities, abdominal bloating, paralysis, and rapid mortality of emerging adult bees. Using specific RT-PCR protocols for the detection of DWV followed by sequencing of the PCR products we could demonstrate that the bumble bees were indeed infected with DWV. The virus was detected from Bombus ignitus, and its partial DWV gene was cloned and sequenced. The partial DWV gene encoding the polyprotein is 711-nt of 235 amino acid residues. The deduced nucleotide sequence of the polyprotein partial gene of DWV showed 96.9%, 96.2%, 96.8%, and 96.5% homology to other structure polyprotein partial gene of DWV from insects, respectively. Phylogenetic analysis further conformed that the deduced nucleotide sequence of the polyprotein partial gene of DWV divided to the outside tree. We describe the first time that presence of Deformed wing virus(DWV) from bumble bee(Bombus terrestris) in korea using RT-PCR.
        87.
        2009.10 구독 인증기관·개인회원 무료
        The traditional use of insects as food continues to be widespread in tropical and subtropical countries and to provide significant nutritional, economic and ecological benefits for rural communities. Specially, Bee brood serves as a food source to humans in many countries although limited data exists concerning its nutrient composition. Bee brood (pupa and larvae) were analyzed for Carbohydrate, Saturated fatty acid, Cholesterol, protein, fat, fiber, minerals, and vitamins. Bee brood was high in protein(46.4%~46.73%), fat(18.84%~ 20.75%),carbohydrate(24.66 %~35.79 %), Folic acid(222.30 ㎍/100g), and vitamins. Differentially, folic acid had been contained by high density in pupa of drone. While low in iron, bee brood was a good source of folic acid, and carbohydrate. The fat was composed mostly of saturated and mono-unsaturated fatty acids. The present data suggest bee brood to be an excellent source of many valuable nutrients including energy, amino acids, many essential minerals, and B-vitamins. These data suggest bee brood could be a valuable source of nutrients to various populations.
        89.
        2007.10 KCI 등재 구독 인증기관·개인회원 무료
        Wntsignaling is involved in the normal development and tumorigenesis via epithelial- mesenchymal transition (EMT). init iated by down-regul ation of E-cadherin by the transc ription factor Snail. Wnt signaling inhi bits Sna il phosph o rylation t hrough Axin2-dependent pathway that sustains nuclear accumul ation 0 1' Snail by driving CSK3ß nucleocytoplasmic export then consequently increases Snail protein levels and induces an EMT However. the roles of Wnt and Axin expression and their functional implication on Snail dependent EMT program a re not clear du ring the multistep carcinogenic process. We examined that canonical Wnt signaling engagingmul t istep carcinogenic process of uterine cervical cancer through Wnt-Axin2-Snail axis. In nonnal cervi cal mucosa, Wntl. Wnt3a. and Axin2 mRNA expression were locali zed in basal cell layer suggesting that canonical Wnt is required for maintenance of self-renewal program of cervica l epi theli al cells. With progression to cervical int r aepithelial neoplasia (CIN) and carcinoma. Wntl, Wnt3a‘ Axin2, and Snail expression were gradually increased in patient samples suggesting that canonical Wnt pathway is involved in earl y step of carcinogenesis in uterine cervix. LRP6 and Axin2 transfected cells showed the highly increased nuclear Snai l resul ted from dec reased level 0 1' nu clear GSK3ß , indicating that LRP6- Axin2 serves to stabili ze Sna il protein levels and susLains iLs nllclear acc llrnulation by driv ing GSK3ß . RNA interference of Axin2 and Snail on SiHa cells relieved E-cadherin proximal promotel‘ activity and block the in 띠 vo chorioalantoic membra ne ln VaSlOn These results suggest the canon ical Wnt signa ling regul ating Axin2-GSK3ß compartmentalization may important for stabi li zation of E- cad herin repressor Snail during the multistep carcinogen ic process of uteri ne cervix. It may lead to not only tracing the proper biomarker 0 [' ca ncer progression‘ but a lso the development oJ new targets for therapeutic intervention in cancer
        94.
        2005.03 구독 인증기관 무료, 개인회원 유료
        Bone remodeling is a process controlled by the action of two major bone cells; the bone forming osteoblast and the bone resorbing osteoclast. In the process of osteoclastogenesis, stromal cells and osteoblast produce RANKL, OPG, and M-CSF, which in turn regulate the osteoclastogenesis. During the bone resorption by activated osteoclasts, extracellular Ca²+/PO₄²- concentration and degraded organic materials goes up, providing the hypertonic microenvironment. In this study, we tested the effects of hypertonicity due to the degraded organic materials on osteoclastogenesis in co-culture system. It was examined the cellular response of osteoblastic cell in terms of osteoclastogenesis by applying the sucrose, and mannitol, as a substitute of degraded organic materials to co-culture system. Apart from the sucrose, mannitol, and NaCl was tested to be compared to the effect of organic osmotic particles. The addition of sucrose and mannitol (25, 50, 100, 150, or 200 mM) to co-culture medium inhibited the number of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells induced by 10 nM (). However, NaCl did exert harmful effect upon the cells in this co-culture system, which is attributed to DNA damage in high concentration of NaCl. To further investigate the mechanism by which hypertonicity inhibits -induced osteoclastogenesis, the mRNA expressions of receptor activator of nuclear factor (NF)-kB ligand (RANKL) and osteoprotegerin (OPG) were monitored by RT-PCR. In the presence of sucrose (50 mM), RANKL mRNA expression was decreased in a dose-dependent manner, while the change in OPG and M-CSF mRNA were not occurred in significantly. The RANKL mRNA expression was inhibited for 48 hours in the presence of sucrose (50 mM), but such a decrement recovered after 72 hours. However, there were no considerable changes in the expression of OPG and M-CSF mRNA. Conclusively, these findings strongly suggest that hypertonic stress down-regulates -induced osteoclastogenesis via RANKL signal pathway in osteoblastic cell, and may playa pivotal role as a regulator that modulates osteoclastogenesis.
        4,000원
        96.
        2003.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        지진하중에 대한 구조물의 동적 거동과 내진성능을 평가하기 위하여 유사동적실험기법이 흔히 사용되고 있으나, 실험장비의 제약과 구조물의 규모 등으로 대부분 축소모형실험에 의존하고 있다. 그러나 일반적인 상사법칙은 탄성범위에서 유도된 것으로 지진거동과 같은 비탄성 거동을 예측하는 경우에는 한계가 있기 때문에 축소모형의 실험결과를 원형 구조물에 직접 적용하는 것은 많은 주의가 필요하다. 본 연구에서는 원형구조물과 축소모형에 대한 철골모형을 실험 대상으로 하여 실제 축소모형 실험결과로부터 원형구조물의 거동을 예측하는 경우의 문제점을 확인하고, 그 해결방법을 모색하고자 한다. 실제로 축소모형실험에서는 원형구조물의 경계조건을 정확히 재현하기 어려우며, 축소모형의 제작과정과 실험과정에서의 모든 오차가 강성의 변화로 반영되어 나타난다. 따라서 본 연구에서는 기하학적 상사율과 축소모형의 변화된 강성비를 함께 고려한 수정된 상사법칙을 제안하였으며, 수정된 상사법칙이 적용된 축소모형에 대하여 유사동적실험을 수행하여 지진응답결과를 원형구조물의 결과와 비교하였다. 축소모형에 대한 유사동적실험결과로부터 제안된 상사법칙을 적용함으로써 원형구조물의 지진응답 재현이 효과적임을 입증하였다.
        4,000원
        97.
        1992.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        키틴생합성저해제인 diflubenzuron을 톱다리개미허리노린재(Riptortus clavatus Thunberg)에 미량국소처리하였을 때 충태 및 영기에 따른 약제의 감수성차이와, 종령약충 처리후 우화율 및 우화성충에 미치는 영향을 조사하였다. Diflubenzuron은 살람효과를 보였으며 산란후 12시간내의 알은 산란후 48~60시간의 알보다 감수성이 높았으나, 알의 나이에 관계없이 처리된 알의 배는 정상적으로 발육하였다. 영기별 감수성은 영기가 진행될수록 낮아져 1령약충이 2령에 비하여 1.5배, 3령약충에 비하여 18.2배, 4령약충에 비하여 39.4배, 5령약충에 비하여 42.4배 높은 감수성을 나타내었다. 종령약충에 처리하였을 때 우화율과 우화성충의 체중, 수명 및 산란율은 현저히 감소하였다.
        4,000원
        98.
        2018.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        Dendropanax morbifera Leveille (Araliaceae) is an endemic species growing in the south-western part of South Korea that has been used in folk medicine and health functional food. In this study, we investigated an extract of quercetin in Jeju D. morbifera by varying different parts (fruit, sprouts, leaves, sprigs, and branches), harvest times, and extraction solvents. In addition, we aimed to establish a simple and reliable HPLC/UV analytical method to determination of quercetin for the quality control and base line data of the Jeju D. morbifera extract as a health functional food ingredient. The analytical specificity was determined with retention time and photo diode array (PDA) spectrum by analyzing quercetin using HPLC and comparing the results to those of extracts. This analytical method for quercetin was validated for its limit of detection (LOD), limit of quantitation (LOQ), precision, and accuracy. A high linearity in the standard calibration curve was obtained, with a coefficient of determination (R2) of 0.9996. Also, the LOD and LOQ values were found to be 0.28 μg/mL and 0.85 μg/mL, respectively, and the recoveries of quantified compounds ranged from 97.91% to 104.10%. Furthermore, the relative standard deviation (RSD) values of data from the intra- and inter-day precision analyses were less than 1.36% and 3.65%, respectively. As a result, the highest quercetin content among the extracts of Jeju D. morbifera leaves was found to be 20.14 mg/g, which was extracted at harvest in May (cultivation period 10 years) with 60% EtOH. All in all, we believe that the results obtained would be helpful in the development of nutraceutics and natural medicines and for the quality control of D. morbifera.
        99.
        2017.11 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        사과는 에틸렌에 의해 호흡량이 일시적으로 상승하는 호흡급등형 과실이다. 에틸렌 발생은 세포벽분해효소 활성화와 세포벽 연화를 진행시켜 사과의 상품성과 저장성을 떨어뜨리는 원인이 된다. 사과의 에틸렌 생합성 과정에는 Md-ACS1 및 Md-ACO1 유전자가 연관되어 있으며, 두 유전자는 과실의 에틸렌 발생량과 경도에 영향을 미치는 것으로 알려져 있다. 본 연구는 사과 국내육성 28품종의 Md-ACS1 및 Md-ACO1 대립유전자형을 분석하고, ‘Fuji(FJ)', ‘RubyS (RS)', ‘Hongro(HR)', ‘Arisoo(AS)', ‘Summer King(SK)', ‘Greenball(GB)', ‘Golden Supreme(GS)'을 대상으로 수확 후 25일까지의 에틸렌 발생량 및 상온저장(20℃) 20일 동안의 경도 연화율을 조사하였다. 그 결과, 낮은 에틸렌 발생량과 관련 된 대립유전자(favorable alleles0(FA)) ACS1-2, ACO1-1이 많을수록 에틸렌 발생량과 경도 연화율이 낮은 경향을 보였다. GS은 ACS1-1/1, ACO1-1/2(FA 1)으로 모든 품종 중 가장 높은 에틸렌 발생 수치와 경도 연화율를 보였다. SK와 GB은 ACS1-1/2, ACO1-1/2(FA 2)으로 ACS1-2/2, ACO1-1/2(FA 3)인 HR와 AS 보다는 높고 GS 보다 낮은 에틸렌 발생량과 경도 연화율을 보였다. ACS1-2/2, ACO1-1/1(FA 4)인 FJ는 RS를 제외한 모든 품종 중에 에틸렌 발생량과 경도 연화율이 가장 낮았다. 본 실험의 결과 Md-ACS1 및 Md-ACO1 대립유전자형과 사과의 에틸렌 발생량 및 경도 연화율은 상관성이 있는 것으로 확인되었다. 따라서, Md-ACS1 및 Md-ACO1 분자표지를 사과 국내육성 품종의 저장성 예측과 육종 효율 향상을 위한 Markerassisted selection에 활용할 수 있을 것으로 생각 된다.
        100.
        2017.05 서비스 종료(열람 제한)
        Background : Pachyrhizus erosus (Leguminosae), locally called as “Yam bean” is a traditional medical plant that grows in the tropical and subtropical region. The root of P. erosus is used by the local people to treat insomania, treatment of osteoporosis and extracts of this plant have shown antioxidant activity, immunomodulatory activity, tyrosinase inhibitionby, antitumour properties and cardiovascular benefit. Methods and Results : Free radical scavenging activity was evaluated using α-tocopherol and butylated hydroxy toluene (BHT) as standard antioxidants. The radical scavenging activity was measured using the stable radical 1,1-diphenyl–2-picrylhydrazyl (DPPH) and ABTS assay. Total phenolic content was determined by following Folin-Ciocalteau colorimetric method and Total flavonoids were determined using aluminium chloride calorimetric methods. Phenolic compound concentration and compositions were determined by HPLC-MS/MS system. Seedlings grown under the flourescent light (Fl) exhibited the highest DPPH radical scavenging activity when compared to the plants treated with light emitting diodes (LEDs) and light emitting plasma (LEP). LED-Blue showed the higher DPPH radical scavenging activity and ABTS concentration of PE compared to other LEDs. The accumulation of phenolic compounds increased under different white-LEDs conditions as compared to LEP and FL light conditions. Conclusion : In this study, antioxidant activity and phenolic compound composition of P. erosus was improved by the application of LED and LEP.
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