• Tuberculosis and Respiratory Diseases
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• 제70권6호
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• pp.482-489
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• 2011

Background: Based on the assertion that apocynin diminishes acute lung injury (ALI) by inhibition of NADPH oxidase, the effect of apocynin was tested in interleukin-$1{\alpha}$ (IL-1)-induced ALI in rats. Methods: IL-1 was insufflated into the trachea of Sprague-Dawley rats to induce ALI, and apocynin (8 mg/kg) was given intravenously for inhibition of NADPH oxidase. In addition, we determined whether apocynin inhibited generation of superoxide anions from isolated human neutrophils. Five hours after IL-1 instillation, lung injury parameters, expression of cytosolic phospholipase A2 (cPLA2) by cells from bronchoalveolar lavage (BAL), an index of oxidative stress in lung tissues (${\gamma}$-glutamyltranspeptidase, activity), and ultrastructure of alveolar type II (AT II) cells were evaluated. Results: Apocynin decreased the generation of free radicals from phorbol myristate (PMA)-activated neutrophils in vitro, but did not ameliorate ALI. IL-1 induced enhancement of the expression of cPLA2 on neutrophils was not altered by apocynin. Conclusion: Apocynin induced suppression of the generation of superoxide anions from neutrophils by inhibition of NADPH oxidase does not attenuate IL-1-induced ALI in rats.

• 생약학회지
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• 제27권2호
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• pp.101-104
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• 1996

Hydrogen peroxide is one of major chemicals mediating antitumor and antimicrobial activities of macrophages. We searched natural products enhancing hydrogen peroxide generation from murine macrophage-like cell line J774. Among 21 methanol extracts of Korean medicinal plants, the extract from Cornus officinalis was the most effective. The active component from the fractions was searched by activity guided fractionation, and identified as ursolic acid by spectral data.

• Natural Product Sciences
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• 제18권1호
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• pp.26-31
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• 2012

Actinidia arguta (Actinidiaceae) has been reported to have several pharmacological effects such as anti-inflammatory, anti-allergic, and anti-oxidant activities. The present study investigated the protective activity of an ethanol extract from the leaf and stem of A. arguta against glutamate-induced neurotoxicity using cultured rat cortical neurons. Exposure of cultured cortical neurons to $500{\mu}M$ glutamate for 12 h triggered neuronal cell death. A. arguta inhibited glutamate-induced neuronal death and apoptosis, which were measured by a 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining, respectively. The increase of pro-apoptotic proteins, Bax and c-caspase-3, in glutamate-treated neurons was significantly inhibited by treatment with A. arguta. A. arguta also inhibited $500{\mu}M$ glutamate-induced elevation of intracellular calcium concentration ($[Ca^{2+}]_i$) and reactive oxygen species (ROS) generation, which were measured by fluorescent dyes, Fluo-4 AM and $H_2DCF$-DA, respectively. These results suggest that A. arguta may prevent glutamate-induced apoptotic neuronal death by inhibiting $[Ca^{2+}]_i$ elevation and ROS generation and, therefore, may have a therapeutic role for the prevention of neurodegeneration in cerebral ischemic diseases.

• 한국전자거래학회지
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• 제5권1호
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• pp.55-73
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• 2000

Recently; EC(Electronic Commerce) is increasing with high speed based on the expansion of Internet. EC which is done on the cyber space through Internet has strong point like independence from time and space. On the contrary, it also has weak point like security problem because anybody can access easily to the system due to open network attribute of Internet. Therefore, we need the solutions that protect the security problem for safe and useful EC activity. One of these solutions is the implementation of strong cipher algorithm. NC(Nonpolynomial Complete) cipher algorithm proposed in this paper is good for the security and it overcome the limit of current 64bits cipher algorithm using 128bits key length for input, output and encryption key, Moreover, it is designed for the increase of calculation complexity and probability calculation by adapting more complex design for subkey generation regarded as one of important element effected to encryption. The result of simulation by the comparison with other cipher algorithm for capacity evaluation of proposed NC cipher algorithm is that the speed of encryption and decryption is 7.63 Mbps per block and the speed of subkey generation is 2,42 μ sec per block. So, prosed NC cipher algorithm is regarded as proper level for encryption. Furthermore, speed of subkey generation shows that NC cipher algorithm has the probability used to MAC(Message Authentication Code) and block implementation of Hash function.

• 대한가정학회지
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• 제35권3호
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• pp.63-75
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• 1997

The purposes of this study was to identify the differences between fashion opinion leaders and followers in the characteristics oriented New Young Generation and the types of fashion advertising involvement. The data were collected via a questionnaire from 431 college students(female=218 male=213) living in Seoul, Korea and analyzed by factor analysis and t-test. The results of this study were as follows: First, eight factors of the characteristics oriented New Young Generation were identified: Fashion, individuality, preference of caffe with affective mood, expression of emotion, indivisualism, preference of tastes oriented Western Europe, activity of pan club and chatting by personal computer. The significant differences between fashion opinion leaders and followers in fashion, individuality, preferences of the caffe with affetive mood, and expression of emotion were found in the data collected from female. There were significant differences between fashion opinion leaders and followers in fashion, individuality in the data collected from male. Second, three factors of fashion involvement advertising were identified: The hedonic involvement, social involvement, utilitarian involvement. The significant differences between fashion opinion leaders and followers in the hedonic involvement, social involvement, utilitarian involvement and the levels of involvement were found in the case of female's data. There were significant differences between fashion opinion leaders and followers in the hedonic involvement, social involvement and levels of involvement except for utilitarian involvement in the case of male's data.

• BMB Reports
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• 제50권6호
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• pp.323-328
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• 2017

Lysophosphatidylcholine (LPC) is a major phospholipid component of oxidized low-density lipoprotein (ox-LDL) and is implicated in its atherogenic activity. This study investigated the effects of LPC on cell viability, intracellular calcium homeostasis, and the protective mechanisms of chlorogenic acid (CGA) in human umbilical vein endothelial cells (HUVECs). LPC increased intracellular calcium ($[Ca^{2+}]_i$) by releasing $Ca^{2+}$ from intracellular stores and via $Ca^{2+}$ influx through store-operated channels (SOCs). LPC also increased the generation of reactive oxygen species (ROS) and decreased cell viability. The mRNA expression of Transient receptor potential canonical (TRPC) channel 1 was increased significantly by LPC treatment and suppressed by CGA. CGA inhibited LPC-induced $Ca^{2+}$ influx and ROS generation, and restored cell viability. These results suggested that CGA inhibits SOC-mediated $Ca^{2+}$ influx and ROS generation by attenuating TRPC1 expression in LPC-treated HUVECs. Therefore, CGA might protect endothelial cells against LPC injury, thereby inhibiting atherosclerosis.

• Asian Pacific Journal of Cancer Prevention
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• 제14권2호
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• pp.895-901
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• 2013

Resistance to induction of apoptosis is a major obstacle for bladder cancer treatment. Bcl-2 is thought to be involved in anti-apoptotic signaling. In this study, we investigated the effect of Bcl-2 overexpression on apoptotic resistance and intracellular reactive oxygen species (ROS) generation in bladder cancer cells. A stable Bcl-2 overexpression cell line, BIU87-Bcl-2, was constructed from human bladder cancer cell line BIU87 by transfecting recombinant Bcl-2 [pcDNA3.1(+)-Bcl-2]. The sensitivity of transfected cells to adriamycin (ADR) was assessed by MTT assay. Apoptosis was examined by flow cytometry and acridine orange fluorescence staining. Intracellular ROS was determined using flow cytometry, and the activities of superoxide dismutase (SOD) and catalase (CAT) were also investigated by the xanthinoxidase and visible radiation methods using SOD and CAT detection kits. The susceptibility of BIU87-Bcl-2 cells to ADR treatment was significantly decreased as compared with control BIU87 cells. Enhanced expression of Bcl-2 inhibited intracellular ROS generation following ADR treatment. Moreover, the suppression of SOD and CAT activity induced by ADR treatment was blocked in the BIU87-Bcl-2 case but not in their parental cells. The overexpression of Bcl-2 renders human bladder cancer cells resistant to ADR-induced apoptosis and ROS might act as an important secondary messenger in this process.

• 한국통신학회논문지
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• 제32권10C호
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• pp.1042-1050
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• 2007

본 논문은 머신 기술 언어를 이용하여 전력 소모가 최소화된 임베디드 코어 자동 생성 시스템의 설계에 대해 기술한다. 머신 기술 언어를 사용하여 어플리케이션에 적합한 임베디드 코어를 빠른 시간에 설계하기 위해 어플리케이션 실행시 동적 전력 소모가 최소화된 코어를 생성하는 시스템을 구축하였다. 제안된 시스템은 각 인스트럭션의 파이프라인 스테이지의 행위 정보로부터 파이프라인 해저드를 찾아내며 처리하는 능력을 가진 임베디드 코어를 생성한다. 생성된 코어는 파워 소모가 최소화되게 만들어져 있다. 자동 생성 시스템의 검증을 위해 ARM9, MIPS R3000에 대해 SMDL로 기술하고 전력 최적화 과정을 거쳐 HDL 코드를 자동 생성하였으며, 어플리케이션에 대해 시뮬레이션을 수행하여 소모되는 전력을 측정하였다. 실험 결과로 생성된 프로세서는 정확한 동작을 수행하였고, 어플리케이션과 생성된 코어에 따라 동적 전력 소모가 $20%{\sim}40%$ 줄어드는 것을 확인하였다.

• 약학회지
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• 제55권6호
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• pp.485-491
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• 2011

Previously, we have reported that apigenin, a natural flavonoid found in a variety of vegetables and fruits, stimulated melanogenesis through the activation of $K^+-Cl^-$-cotransport (KCC) in B16 melanoma cells. In this study we investigated the possible involvement of reactive oxygen species (ROS) in the mechanism of apigenin-induced melanogenesis in B16 cells. Apigenin elevated intracellular ROS level in a dose-dependent manner. Treatment with various inhibitors of NADPH oxidase, diphenylene iodonium (DPI), apocynin (Apo) and neopterine (NP) significantly inhibited both the generation of ROS and melanogenesis induced by apigenin. In addition these inhibitors profoundly inhibited apigenin-induced $Cl^-$-dependent $K^+$ efflux, a hallmark of KCC activity. However, the apigenin-induced ROS generation was not significantly affected by treatment with a specific KCC inhibitor R-(+)-[(2-n-butyl-6,7-dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1H-inden-5-yl)oxy]acetic acid (DIOA). These results indicate that the ROS production may be a upstream regulator of the apigenin-induced KCC stimulation, and in turn, melanogenesis in the B16 cells. Taken together, these results suggest that the NADPH oxidase-mediated ROS production may play an important role in the apigenin-induced melanogenesis in B16 cells. These results further suggest that NADPH oxidase may be a good target for the management of hyperpigmentation disorders.

• BMB Reports
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• 제41권8호
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• pp.555-559
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• 2008

Reactive oxygen species (ROS) are generated in mammalian cells via both enzymatic and non-enzymatic mechanisms. Although certain ROS production pathways are required for the performance of specific physiological functions, excessive ROS generation is harmful, and has been implicated in the pathogenesis of a number of diseases. Among the ROS-producing enzymes, NADPH oxidase is widely distributed among mammalian cells, and is a crucial source of ROS for physiological and pathological processes. Reactive oxygen species are also generated by arachidonic acid (AA) metabolites, which are released from membrane phospholipids via the activity of cytosolic phospholipase $A_2$ ($cPLA_2$). In this study, we describe recent studies concerning the generation of ROS by AA metabolites. In particular, we have focused on the manner in which AA metabolism via lipoxygenase (LOX) and LOX metabolites contributes to ROS generation. By elucidating the signaling mechanisms that link LOX and LOX metabolites to ROS, we hope to shed light on the variety of physiological and pathological mechanisms associated with LOX metabolism.