• Toxicological Research
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• 제17권
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• pp.83-88
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• 2001

Most reactive oxygen species (ROS) are free radicals and implicated in the development of a number of disease processes including artherosclerosis, neurodegenerative disorders, aging and cancer. ROS are byproducts of a number of in vivo metabolic processes and are formed deliberately as part of nor-mal inflammatory response. On the other hand, ROS are generated either as by products of oxygen reduction during xenobiotic metabolism or are liberated as the result of the futile redox cycling of the chemical agents including several chemical carcinogens. A better understanding of the mechanisms of free radical toxicity may yield valuable clue to risks associated with chemical exposures that leading to the development of chronic diseases including cancer. The molecular biology of ROS-mediated alterations in gene expression, signal transduction and carcinognesis is one of the important subjects in free radical toxicology. Epidemiological studies suggest that high intake of vegetables and fruits are associated with the low incidence of human cancer. Many phytopolyphenols such as tea polyphenols, curcumin, resveratrol, apigenin, genistein and other flavonoids have been shown to be cancer chemopreventive agents. Most of these compounds are strong antioxidant and ROS scavengers in vitro and effective inducers of antioxidant enzymes such as superoxide dismutatse, catalase and glutathione peroxidase in vivo. Several cellular transducers namely receptor tyrosine kinase, protein kinase C, MAPK, PI3K, c-jun, c-fos, c-myc, NFkB, IkB kinase, iNOS, COX-2, Bcl-2, Bax, etc have been shown to be actively modulated by phyto-polyphenols. Recent development in free radical toxicology have provided strong basis for understanding the action mechanisms of cancer chemoprevention.

• Molecules and Cells
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• 제37권3호
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• pp.196-201
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• 2014

Pulmonary arterial hypertension (PAH) is a progressive disease characterized by the vascular remodeling of the pulmonary arterioles, including formation of plexiform and concentric lesions comprised of proliferative vascular cells. Clinically, PAH leads to increased pulmonary arterial pressure and subsequent right ventricular failure. Existing therapies have improved the outcome but mortality still remains exceedingly high. There is emerging evidence that the seven-transmembrane G-protein coupled receptor APJ and its cognate endogenous ligand apelin are important in the maintenance of pulmonary vascular homeostasis through the targeting of critical mediators, such as Kr$\ddot{u}$ppel-like factor 2 (KLF2), endothelial nitric oxide synthase (eNOS), and microRNAs (miRNAs). Disruption of this pathway plays a major part in the pathogenesis of PAH. Given its role in the maintenance of pulmonary vascular homeostasis, the apelin-APJ pathway is a potential target for PAH therapy. This review highlights the current state in the understanding of the apelin-APJ axis related to PAH and discusses the therapeutic potential of this signaling pathway as a novel paradigm of PAH therapy.

• 동의생리병리학회지
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• 제18권6호
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• pp.1622-1627
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• 2004

Nephrite has been widely used as a medicinal mineral resource to treat a numerous chronic diseases and to replenish vital essence and blood in the Korean traditional medicine. However, as of yet, there is little understanding of the pharmacological and biochemical mechanisms of its therapeutic effects as regards anti-inflammation. We therefore examined whether nephrite represses the expression of major inflammation mediators, such as interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2), in LPS-stimulated murine macrophage cell line, RAW264.7 by using RT-PCR. The powder suspension and water extracts of nephrite significantly inhibited the mRNA expression of the mediators, despite a little toxic effects on growth of RAW 264.7 cells within the concentration range tested. These experimental results suggested that the nephrite can be utilized as a functional mineral exerting the anti-inflammation medicinal effect.

• Tuberculosis and Respiratory Diseases
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• 제52권6호
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• pp.616-626
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• 2002

연구배경 : PM2.5는 호흡기질환의 악화 및 호흡기 질환에 의한 사망률과 밀접하게 관계가 있다. PM2.5에 의한 호흡기 염증반응의 악화가 그 원인으로 생각되나 염증반응의 조절기전은 확실하지 않다. 본연구에서는 PM2.5에 의한 폐장의 염증반응을 조절하는데 중요한 역할을 하는 전사인자인 $NF{\kappa}B$의 활성화 기전을 알아보아 염증 조절기전에 대한 이해를 높이고자 시도되었다. 방 법 : 폐상피세포주인 A549 세포에서 PM2.5 자극에 의한 $NF{\kappa}B$의 활성화 및 ROS, 그리고 RNS 분비를 관찰 하였다. iNOS 억제제인 L-NIL가 $NF{\kappa}B$ 활성화에 미치는 영향을 관찰하였다. 결 과 : PM2.5는 A549 세포에서 $NF{\kappa}B$의 활성화를 유도 하였다. PM2.5로 A549 세포를 자극시 즉각적인 RNS의 분비는 관찰되었으나 명확한 ROS의 증가는 관찰되지 않았다. RNS 억제제인 L-NIL 처리시 $NF{\kappa}B$ 활성화는 억제되었다. 결 론 : A549 세포에서 PM2.5에 의하여 유도된 즉각적인 $NF{\kappa}B$ 활성화 과정에는 RNS가 중요한 역할을 할 것으로 생각된다.

• 한국한의학연구원논문집
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• 제14권3호
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• pp.57-63
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• 2008

Glehnia littoralis (Umbelliferae) is the medicinal plant used traditionally for treatment of immune-related diseases. Prostaglandins and nitric oxide (NO) have been implicated as important mediators in the processes of inflammation and carcinogenesis. For understanding the mechanisms for pharmacological activities of Glehnia littoralis, we evaluated the inhibitory activity of Glehnia littoralis on lipopolysaccharide (LPS)-induced prostaglandin $E_2$ ($PGE_2$) and NO production in mouse macrophage RAW264.7 cells. The results showed that the extract of Glehnia littoralis inhibited LPS- induced $PGE_2$ production effectively, but not NO. Additional study revealed that the extract of Glehnia littoralis suppressed cyclooxygenase-2 (COX-2) expression in a dose-dependent manner. Present study suggests that Glehnia littoralis may have anti-inflammatory and/or cancer chemopreventive activity through the inhibition of $PGE_2$ production by the suppression of COX-2 activity.

• The Korean Journal of Physiology and Pharmacology
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• 제16권3호
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• pp.219-224
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• 2012

Understanding how the b-wave of the electroretinogram (ERG) is generated by full-field light stimulation is still a challenge in visual neuroscience. To understand more about the origin of the b-wave, we studied the contributions of gap junctions to the ERG b-wave. Many types of retinal neurons are connected to similar and different neighboring neurons through gap junctions. The photopic (cone-dominated) ERG, stimulated by a small light beam, was recorded from goldfish (Carassius auratus) using a corneal electrode. Data were obtained before and after intravitreal injection of agents into the eye under a photopic illumination level. Several agents were used to affect gap junctions, such as dopamine D1 and D2 receptor agonists and antagonists, a nitric oxide (NO) donor, a nitric oxide synthase (NOS) inhibitor, the gap junction blocker meclofenamic acid (MFA), and mixtures of these agents. The ERG b-waves, which were enhanced by MFA, sodium nitroprusside (SNP), SKF 38393, and sulpiride, remained following application of a further injection of a mixture with MFA. The ERG b-waves decreased following $N^G$-nitro-L-arginine methyl ester (L-NAME), SCH 23390, and quinpirole administration but were enhanced by further injection of a mixture with MFA. These results indicate that gap junction activity influences b-waves of the ERG related to NO and dopamine actions.

• IMMUNE NETWORK
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• 제9권2호
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• pp.46-52
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• 2009

Although tuberculosis poses a significant health threat to the global population, it is a challenge to develop new and effective therapeutic strategies. Nitric oxide (NO) and inducible NO synthase (iNOS) are important in innate immune responses to various intracellular bacterial infections, including mycobacterial infections. It is generally recognized that reactive nitrogen intermediates play an effective role in host defense mechanisms against tuberculosis. In a murine model of tuberculosis, NO plays a crucial role in antimycobacterial activity; however, it is controversial whether NO is critically involved in host defense against Mycobacterium tuberculosis in humans. Here, we review the roles of NO in host defense against murine and human tuberculosis. We also discuss the specific roles of NO in the central nervous system and lung epithelial cells during mycobacterial infection. A greater understanding of these defense mechanisms in human tuberculosis will aid in the development of new strategies for the treatment of disease.

• 한국초등과학교육학회지:초등과학교육
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• 제38권2호
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• pp.203-215
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• 2019

The purpose of this study is to clarify the roles of laboratory work in school. Twenty-one literatures were identified about roles of laboratory work in school by applying criteria such as published in CI level journals or used as a reference over 100 times during 1960-2017. Twenty-one literatures were reviewed according to periods such as 1960-1989, 1990-2003, and 2004-2017, and identified the roles of laboratory work in school that commonly presented in more than two literature. Seven roles of laboratory work in school identified were as follows (a) learning scientific knowledge, (b) enhancing attitude toward science, (c) learning scientific inquiry methods, (d) acquiring skills to use specific laboratory instruments, (e) enhancing scientific attitude, (f) understanding the nature of science(NOS), and (g) providing opportunity to experience natural or scientific phenomena. The results of this study can be used to provide school teachers and students a clear meaning of the roles of laboratory work in school.

• 한국지구과학회지
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• 제37권6호
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• pp.373-386
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• 2016

본 연구는 국내 원자력방사선 관련 전시 및 교육 발전 방향을 모색하기 위하여 국내 원자력 홍보관의 전시물 및 전시패널을 내용에 따라 크게 4가지 범주로 분류하고, 과학커뮤니케이션의 6가지 요소로 분석하여 비율을 파악하였다. 연구 대상은 국내 원자력 홍보관 총 4곳을 목적 표집하였으며, 일본의 원자력 과학관 1곳을 선정하였다. 연구 결과, 국내 모든 기관에서는 4가지 범주 중에서 개념에 해당하는 내용이 높은 비율로 나타났다. 그리고 전시물에 포함되어 있는 과학커뮤니케이션 요소는 개념(CON)과 흥미(INT)가 주를 이루었으며, 반면에 과학의 본성(NOS), 인식(AW), 즐거움(ENJ), 의견(OP)은 제한적으로 나타났다. 본 연구결과를 통하여 다음과 같은 결론을 내릴 수 있다. 원자력 홍보관은 관람객에게 원자력방사능에 대한 다양한 측면의 정보를 제공하여 관람객 스스로 올바른 판단을 하고 과학적 태도를 향상시키며 과학커뮤니케이션 요소의 이해를 높일 수 있도록 과학적 소양인 양성을 위한 전문 비형식 교육기관으로써의 역할을 수행할 수 있어야 한다. 그리고 전시물에 반영하기 어려운 과학커뮤니케이션을 충족시킬 수 있도록 전문 도슨트 또는 해설사 양성을 위한 전문 프로그램 개발과 적용에 대한 지속적인 연구가 필요하다.

• IMMUNE NETWORK
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• 제10권4호
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• pp.135-143
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• 2010

Background: Cordyceps militarys water extract (CME) has been reported to exert antitumor and immunomodulatory activities in vivo and in vitro. However, the therapeutic mechanism has not yet been elucidated. In this study, we examined the effects of CME on the antigen presenting function of antigen presenting cells (APCs). Methods: Dendritic cells (DCs) were cultured in the presence of CME, and then allowed to phagocytose microspheres containing ovalbumin (OVA). After washing and fixing the efficacy of OVA, peptide presentation by DCs were evaluated using CD8 and CD4 T cells. Also, we confirmed the protein levels of proinflammatory cytokines through western blot analysis. Results: CME enhanced both MHC class I and class II-restricted presentation of OVA in DCs. In addition, the expression of both MHC class I and II molecules was enhanced, but there was no changes in the phagocytic activity of exogenous OVA. Furthermore, CME induced the protein levels of iNOS, COX-2, proinflammatory cytokines, and nuclear p65 in a concentration-dependent manner, as determined by western blot. Conclusion: These results provide an understanding of the mechanism of the immuno-enhancing activity of CME on the induction of MHC-restricted antigen presentation in relation to their actions on APCs.