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      • KCI등재

        Effects of epigallocatechin gallate on CoCl_(2)-induced apoptosis in PC12 cells

        Yang, Kyu-Ho,Mo, Hyun-Chul,Choi, Nam-Ki,Kim, Seon-Mi,Kim,Won-Jae 大韓小兒齒科學會 2006 大韓小兒齒科學會誌 Vol.33 No.1

        Neuronal apoptotic events, consequently resulting in neuronal cell death, are occurred in hypoxic/ischemic condition. This cell death has been shown to be accompanied with the production of reactive oxygen species (ROS), which can attack cellular components such as nucleic acids, proteins and phospholipid. However, the underlying mechanisms of apoptosis induced in hypoxic/ischemic condition and its treatment methods are unsettled. Cobalt chloride (CoCl_(2)) has been known to mimic hypoxic condition including the production of ROS. Epigallocatechin gallate (EGCG). a green tea polyphenol, has diverse pharmacologial activities in cell growth and death. This study was aimed to investigate the apoptotic mechanism by CoCl_(2) and effects of EGCG on CoCl_(2)-induced apoptosis in PC12 cells. Administration of CoCl_(2) decreased cell survival in dose- and time-dependent manners and induced genomic DNA fragmentation. Treatment with 100 µM EGCG for 30 min before PC12 cells were exposed to 150 µM CoCl_(2), being resulted in the cell viability and DNA fragmentation being rescued. CoCl_(2) caused morphologic changes such as cell swelling and condensed nuclei, whereas EGCG attenuated morphologic changes by CoCl_(2). EGCG suppressed the apoptotic peak and a loss of Δψ_(m) induced by CoCl_(2). CoCl_(2) decreased Bcl-2 expression but Bax expression was not changed in CoCl_(2)-treated cells. EGCG attenuated the Bcl-2 underexpression by CoCl_(2). CoCl_(2) augumented the cytochrome c release from mitochondria into cytoplasm and increased caspase-8, -9 and caspase-3 activity, a marker of the apoptotic executing stage. EGCG ameliorated the incruement in caspase-8, -9 and -3 activity, and cytochrome c release by CoCl_(2). NAC (N-acetyl-cysteine), a scavenger of ROS, attenuated CoCl_(2)-induced apoptosis in consistent with those of EGCG. These results suggest, that CoCl_(2) induces apoptotic cell death through both mitochondria- and death receptor-dependent pathway and EGCG has neuroprotective effects against CoCl_(2)-induced apoptosis in PC12 cells. 신경세포자멸사는 저산소 및 허혈환경에서 일어나며 이러한 세포죽은 reactive oxidant species (ROS) 생성을 동반함이 알려져있다. 그러나, 저산소 및 허혈환경에서 일어나는 세포자멸사의 기전 및 그 치료방법은 아직 정립되어 있지 않다. CoCl_(2)는 ROS를 생성하는 등 저산소환경과 유사한 조건을 초래하는 것으로 알려져 있다. Epigallocatechin gallate (EGCG)는 녹차의 polyphenol 성분으로서 세포성장과 죽음에 다양한 약리학적 효과를 나타냄이 알려져 있다. 본 연구는 PC12 세포에서 CoCl_(2)에 의한 세포자멸사기전을 밝히고 이에 미치는 EGCG의 효과를 조사하는데 목적이 있다. Cell viability는 MTT 측정으로 조사되었고, DNA fragmentation은 DNA laddering으로 조사되었다. Bcl-2와 Bax발현 정도는 RT-PCR로, caspase-3와 -9의 활성은 spectrophotometer, caspase-8의 활성은 flow cytometry에 의해 측정되었다. 미토콘드리아에서 세포질로 분비된 cytochrome c는 western blot으로, 분해된 DNA 양과 미토콘드리아 세포막전위 (Δψ_(m))는 FACScan으로 조사되었다. CoCl_(2)투여로 PC12 세포수는 용량 및 시간 의존형태로 감소하였고, genomic DNA fragmentation이 발생하였다. CoCl_(2)투여로 야기된 cell viability의 감소와 DNA fragmentation은 EGCG 전처치에 의해 억제되었다. CoCl_(2)은 세포용적팽창과 condensed nuclei 같은 형태적 변화를 일으켰으며, apoptotic peak, Δψ_(m)감소 및 cytochrome c 유리를 야기하였다. EGCG는 CoCl_(2)에 의한 세포형태변화, apoptotic peak, Δψ_(m)소실 및 cytochrome c 유리를 억제시켰다. CoCl_(2)는 Bcl-2 발현을 감소시켰지만, Bax 발현에는 영향을 미치지 않았다. EGCG는 CoCl_(2)에 의해 야기된 Bcl-2 발현 감소를 억제시켰다. CoCl_(2)는 caspase-3, -8, 그리고 -9의 활성을 증가시켰으며, EGCG는 CoCl_(2)에 의한 세포자멸사를 억제시켰다. 본 실험결과는 PC12 세포에서 CoCl_(2)가 미토콘드리아 의존 및 death receptor의존 기전으로 세포자멸사를 일으키며, EGCG는 세포자멸사기전을 억세지킴으로 신경보호기능을 가짐을 시사하였다.

      • KCI등재후보

        납에 의해 유발된 신경세포의 APOPTOSIS

        양선희,신동훈,백원기 大韓産業醫學會 1999 대한직업환경의학회지 Vol.11 No.2

        Lead is a major environmental and occupational neurotoxicant. It has been shown that long-term exposure to a low level of lead impairs the development of brain. For example, it was reported that lead exposure during the childhood causes a learning difficulty and a memory deficit of children. Neurotoxic agents including the lead are believed to cause neuronal death in developing brain by two mechanisms: apoptosis and necrosis. However, the exact mechanism of neuronal death caused by lead exposure is still not known explicitly. In this study, we conducted a study to clarify a mechanism of hippocampal neuronal cell death caused by lead acetate. Hippocampal neurons were cultured for 14-16days and treated with lead acetate of 1, 10, 100μM concentrations for 12 hours. With the MTT (methyl tetrazolium test)kit, the viability of neuronal cells was measured. Next, in order to examine apoptosis caused by lead acetate, TUNEL(TdT-mediated d-UTP Nick End Labelling ) assay was performed. It has been shown that lead acetate reduced the viability of neuronal cells in a dose dependent manner, especially at the concentration of 100 μM lead acetate. TUNEL immunostain showed brownish signals in the nucleus of apoptotic cells. The proportions of apoptotic cells in the lead-acetate treated group were more higher than those in the controls and increased as lead acetate concentration increased. From above results, it may be concluded that lead in the hippocampal neuronal cells reduced cell viability and one of mechanisms in neuronal cell death by lead appears to be apoptosis.

      • 방아의 각종 용매 추출물의 항산화 효과

        원선임,지옥화,양차범 漢陽大學校 韓國生活科學硏究所 1995 韓國 生活 科學 硏究 Vol.- No.13

        Bangah(Agastache rugosa O. Kuntze), one of the herbs grown in Korea, was investigated for its antioxidant activity. Several antioxidative fractions was obtained from Bangah powder by extraction with variours single and mixed solvents. The free, esterified and insoluble-bound phenolic acids were fractioned with using methanol - acetone solvents and added into the soybean oil and lard at the level of 200ppm. The antioxidative activity was measured by peroxide value, carbonyl value and induction time during storage at 60℃. The results were as follows : 1.The extract yield obtained from Bangah powder was increased as the polarity of the solvents increased. 2.The antioxidative effect of the Bangah extracts obtained with single solvent extraction was found in lard in the order of dioxane>methanol>ethyl ether, while those extracts showed little effects on soybean oil. Extraction with using mixed solvents showed no significant improvement in the antioxidative effects. 3.A significant antioxidative effect of phenolic acid fraction was observed on lard, while the effecet was little on soybean oil. The insoluble phenolic arid fraction among the three phenolic acid fractions showed the highest antioxidative effect. When the phenolic acid fractions were added in the range of 200∼1000ppm, the antioxidant effect was observed at 1000ppm for soybean oil and 400ppm for lard.

      • KCI등재
      • SCOPUSSCIEKCI등재

        성장기 아동과 성인에서의 Ⅱ급 1류 부정교합치료양상에 관한 두부방사선 계측학적 비교연구 : ADOLESCENTS CONTRASTED WITH ADULTS

        강보선,양원식 대한치과교정학회 1995 대한치과교정학회지 Vol.25 No.3

        본 연구는 Ⅱ급 1류 부정교합의 치료에 있어 치료전의 환자연령에 따른 부정교합치료의 양적 차이를 알아보고, Johnston analysis를 통해 협측 치열군의 교정이 어떤 방법으로 이루어지는지, 즉, 두개저에 대한 또한 상호간에 대한 상, 하악 각각의 성장양과 기저골에 대한 구치의 이동양을 측정하여 구치부의 교정이 어떻게 이루어지는지를 알아보고자 했으며 서울대학교병원 치과진료부 교정과에 내원하여 Ⅱ급 1류 부정교합으로 진단되어 상, 하악 제1소구치를 발치하여 치료를 받은 여자환자 52명중 치료전의 연령을 기준으로 성장기 아동군과 성인군으로 대별하여 치료전,후 두부방사선사진을 계측, 비교분석하여 다음과 같은 결론을 얻었다. 1. 치료전,후의 상악골의 전후방적인 위치변화에 대한 비교를 통해서 성장기 아동군과 성인군간의 유의한 차는 없었다. 그러나 하악골의 전후방적 위치변화에 있어서는 두 군간에 유의한 차이를 보였다.(p<0.05) 2. 치료 전,후 수직고경의 변화에 있어, 성장기 아동군에서는 전안면고경, 후안면 고경, 하안면고경 등이 성장과 치료의 효과로 유의성있게 증가하였으며(p<0.001), 성인군에서는 유의성있는 변화가 없었다. 3. 치료전,후 교합평면의 변화에 있어, 성장기 아동군에서는 교합평면의 경사도의 유의성있는 변화가 발견되지 않았으나, 성인군에서는 교합평면의 경사도가 유의성있게 증가하였다.(p<0.05) 4. Johnston analysis를 이용한 분석으로, total molar correction의 양에 있어서 성장기 아동군과 성인군에서 유의한 차이를 보였다.(p<0.05) 5. Johnston analysis를 이용한 분석에 의해 성장기 아동군에서는 total molar correction의 63%가 하악골성장에 의해, 37%가 치아이동에 의해 이루어짐을 관찰했다. 성인군에서는 total molar correction의 99%가 치아이동에 의해 이루어졌다. The purpose of this study was to quantitate differences in the nature of the correction of Angle's Class Ⅱ div 1 malocclusion dependent on the patient's age at the time of treatment. The sample consisted of 27 female patients in the adolescent group with a mean initial records age of 11.8 years and 25 female patients in the adult group with a mean starting age of 21.1 yrs. Lateral cephalometric head films were taken before and after orthodontic treatment with four bicuspid extraction. The results were obtained as follows. 1. None of maxillary skeletal parameters exhibited a significantly different in tretment change between adolescents and adults. But, in mandibular skeletal measurements, there were significant differences between two groups.(p<0.05) 2. Measures of vertical dimension in the adults remained unchanged during treatment, reflecting the effective absence of growth. 3. The steepness of occlusal plane in the adults changed significantly.(p<0.05) In contrast, the adolescents displayed stability of the occlusal plane. 4. According to the Johnston analysis, there was a significant difference in the total molar correction between two groups.(p<0.05) 5. According to the Johnston analysis, differential mandibular growth in the adolescents contrubuted 63% of the total molar correction, with orthodontic tooth movement accounting for the remaining 37%. In the adults, dental movements comprised 99% of the correction.

      • 급성 백혈병 환자에서 발생한 감염 양상의 분석(1986~1992)

        박선양,오명돈,김양수,백경란,김병국,최강원,김성민 대한감염학회 1993 감염 Vol.25 No.3

        Infection is a major complication and potentially life-threatening in patients with acute leukemia. The patients require prompt broad-spectrum antibiotics therapy when fever develops. One of the keys to successful patient management is the recognition of institutional trends of the spectrum of infections and infecting microorganisms. So we evaluated 138 patients with acute leukemia and blastic crisis of chronic myelogenous leukemia admitted to Seoul National University Hospital from July 1986 to June 1992. The results are following: 1) Total number of febrile episodes was 224 and 60% of them occurred after chemotherapy. 2) Microbiologically-defined infection, clinically-defined infection, and unexplained fever accounted for 28%, 45%, 27% of the febrile episodes respectively. 3) Fifty-eight percent of microbiologically-defined infections were caused by gram-negative bactria, and 36% were gram-positive bacteria. There was a tendency to a greater proportion of gram (+) organisms than that of the last study (p>0.1). Escherichia coli was the most common organism, and coagulase-negative staphylococci, Pseudomonas aeruginosa, Klebsiella pneumoniae were common in decreasing order. 4) Pneumonia was the most common type of infection, followed by skin and soft tissue infection, perianal infection, gingivitis and primary septicemia. 5) Seventy-two percent of total infections improved with therapy and this success rate was higher than that of the last study(p<0.001).

      • KCI등재

        활성화 수피를 이용한 중금속 흡착제 개발

        박창진,양재의,유경열,장용선,김원일 한국환경농학회 2004 한국환경농학회지 Vol.23 No.4

        The objective of this research was to develop the adsorbent for heavy metals by activating the bark sample. Barks from pine tree with diameters of 2~4 mm were activated in the muffle furnace under a high relative humidity condition at temperatures of 600~900℃. The removal efficiency of the activated bark (ACTBARK) for Cu and Cd was temperature dependent showing the order of 900℃ > 800℃ > 700℃ > 600℃. The critical temperature was considered to be 900℃ to become an efficient adsorbent for Cu and Cd. The bark samples activated at temperatures lower than 700℃ showed a less removal efficiency than the crude bark The ACTBARK activated at 900℃ removed more Cu and Cd from solution than the commercial activated carbon and charcoal. The ACTBARK (activated at 900℃) adsorbed all of the Cu and Cd in solution with concentrations less than 150 mg/L. The selectivity of the ACTBARK was in the order of Cu>Zn>Ni>Pb>Fe>Cd>Mn.

      • KCI등재

        Swivel joint를 이용한 비대칭 발치증례의 교정적 공간폐쇄

        고창희,임성훈,김광원,정동기,김도영,박선주,양용근 조선대학교 구강생물학연구소 2003 口腔生物學硏究 Vol.27 No.1

        Extraction therapy is popular treatment protocol in orthodontics. Generally, symmetric premolar extraction is performed. But, in some cases, asymmetric extraction is required to solve asymmetric dental alignment. But asymmetric extraction treatment has side effects and disadvantages like a) collapse of dental arch form. b) canting of occlusal plane, c) extended treatment duration. For a good treatment result, we applied the orthodontic space closing arch wire with swivel joint to allow rotational movement of arch wire segments during space closure, Now we present a case treated with orthodontic space closing arch wire with swivel joint.

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