• 대한화장품학회지
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• 제20권1호
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• pp.25-36
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• 1994

Gram 음성균의 세포벽 성분인 lipopolysaccharide는 각종 세포에서의 prostaglandin 합성을 증진 시키며 이는 cyclooxygenase-2의 선택적 발현에 기인한다는 사실이 이미 보고된 바 있다. 본 연구에서는 mouse peritoneal marophage를 대상으로 하여 LPS의 prostaglandin 합성 증진 작용에 대한 특성으로 검토함으로써, COX-2에 대한 선택적 저해제 검색에 이용될 수 있는지 그 가능성을 확인코자 하였다. LPS는 peritoneal macrophage에 처리시 약 8시간 정도의 lag time을 보인 후 prostaglandin 합성을 현저히 증진 시켰으며, 이는 주로 COX 활성의 증가에 기인하는 것으로 추정되었다. 또한 LPS의 작용은 항염증제인 dexamethasone에 의해서 강하게 억제 되었으며 metabolic labeling 결과 이는 COX-2의 생합성을 억제하는데 기인하는 것으로 확인되었다. 따라서 mouse peritoneal macrophage에서의 LPS에 의한 prostaglandin 합성 증진 작용은 rat alveolar macrophage와 정성적으로 동일함을 확인할 수 있었으며, 본 실험 조건은 COX-2에 대한 선택적 저해제 검색에 응용될 수 있음을 확인 하였다. 본 실험 조건하에서 비스테로이드성 항염제인 ketoprofen의 작용을 검토한 결과 ketoprofen은 COX-1에 비교적 선택적인 저해 작용을 보이는 것으로 추정 되었다.

• Biomolecules & Therapeutics
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• 제21권1호
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• pp.54-59
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• 2013

In this study, we investigated the effect of (-)-epigallocatechin-3-gallate (EGCG), a major component of green tea catechins from green tea leaves, on activities of cyclooxygenase (COX)-1 and thromboxane synthase (TXAS), thromboxane $A_2$ ($TXA_2$) production associated microsomal enzymes. EGCG inhibited COX-1 activity to 96.9%, and TXAS activity to 20% in platelet microsomal fraction having cytochrome c reductase (an endoplasmic reticulum marker enzyme) activity and expressing COX-1 (70 kDa) and TXAS (58 kDa) proteins. The inhibitory ratio of COX-1 to TXAS by EGCG was 4.8. These results mean that EGCG has a stronger selectivity in COX-1 inhibition than TXAS inhibition. In special, a nonsteroid anti-inflammatory drug aspirin, a COX-1 inhibitor, inhibited COX-1 activity by 11.3% at the same concentration ($50{\mu}M$) as EGCG that inhibited COX-1 activity to 96.9% as compared with that of control. This suggests that EGCG has a stronger effect than that of aspirin on inhibition of COX-1 activity. Accordingly, we demonstrate that EGCG might be used as a crucial tool for a strong negative regulator of COX-1/$TXA_2$ signaling pathway to inhibit thrombotic disease-associated platelet aggregation.

• 대한약침학회지
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• 제20권3호
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• pp.207-212
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• 2017

Objectives: Study of the mechanisms involved in cancer progression suggests that cyclooxygenase enzymes play an important role in the induction of inflammation, tumor formation, and metastasis of cancer cells. Thus, cyclooxygenase enzymes could be considered for cancer chemotherapy. Among these enzymes, cyclooxygenase 2 (COX-2) is associated with liver carcinogenesis. Various COX-2 inhibitors cause growth inhibition of human hepatocellular carcinoma cells, but many of them act in the COX-2 independent mechanism. Thus, the introduction of selective COX-2 inhibitors is necessary to achieve a clear result. The present study was aimed to determine the growth-inhibitory effects of new analogues of chalcone epoxide as selective COX-2 inhibitors on the human hepatocellular carcinoma (HepG2) cell line. Methods: Estimation of both cell growth and the amount of prostaglandin E2 (PGE2) production were used to study the effect of selective COX-2 inhibitors on the hepatocellular carcinoma cell. Cell growth determination has done by MTT assay in 24 h, 48 h and 72 h, and PGE2 production has estimated by using ELYSA kit in 48 h and 72 h. Results: The results showed growth inhibition of the HepG2 cell line in a concentration and time-dependent manner, as well as a reduction in the formation of PGE2 as a product of COX-2 activity. Among the compounds those analogues with methoxy and hydrogen group showed more inhibitory effect than others. Conclusion: The current in-vitro study indicates that the observed significant growth-inhibitory effect of chalcone-epoxide analogues on the HepG2 cell line may involve COX-dependent mechanisms and the PGE2 pathway parallel to the effect of celecoxib. It can be said that these analogues might be efficient compounds in chemotherapy of COX-2 dependent carcinoma specially preventing and treatment of hepatocellular carcinomas.

• Tuberculosis and Respiratory Diseases
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• 제63권1호
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• pp.31-41
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• 2007

연구배경: 폐암의 병인에 기여하거나 예후를 결정하는 인자에 대해서는 매우 다양한 인자와 다양한 상호 관계로 인하여 특히 유전자의 역할에 대해서는 결정적으로 알려진 것이 없어 앞으로 더 많은 연구가 필요한 실정이다. 이에 따라 본 연구에서는 COX-2, MMP-9, p53가 비소세포폐암에서 어떻게 발현되는지 세포면역학적으로 알아보고 임상 특성과 예후와 상관관계를 알아보고자 하였다. 대상 및 방법: 91명의 비소세포폐암을 대상으로 하여 후향적으로 임상특성을 고찰하고 COX-2, MMP-9, p53의 유전자 표현을 세포면역학적 방법을 통하여 검사하였다. 임상특성과 유전자 표현 패턴의 상관관계와 생존에 대한 예후인자로서의 역할에 대하여 조사하였다. 결 과: 1) 편평상피세포암에서는 흡연자과 남자가 우세한 비율을 차지하였으며 남자에서 흡연의 비율이 유의하게 높았다. 2) 전체 대상 환자에서 생존에 영향을 미치는 결정적인 인자는 근치적 절제술의 시행여부와 병기로 나타났다. 3) COX-2의 발현은 편평상피세포암 보다 선암에서 더 유의하게 높게 발현되었다. 4) COX-2, MMP-9, p53의 발현이 모두 되지 않는 비율은 선암에 비해 편평상피세포암에서 더 흔하게 관찰되었다. 5) p53돌연변이가 있으면서 COX-2와 MMP-9은 발현이 되지 않는 비소세포폐암환자의 생존기간이 다른 발현 양상을 보이는 경우에서의 생존기간보다 더 연장되어 보였다(생존기간의 중앙값; 165.6주). 6) COX-2의 발현과 MMP-9의 발현 사이에는 유의한 상관관계가 있었다. 7) 폐암을 근치적으로 절제한 환자의 경우에 COX-2의 발현은 유의한 예후인자였다. MMP-9는 근치적 절제술을 받지 못한 환자군에서 유의한 예후인자로 작용하였다.

• 대한골관절종양학회지
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• 제13권2호
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• pp.105-112
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• 2007

목적: 최근 골 및 연부조직 종양을 포함한 각종 악성 종양에서 cyclooxygenase-2 (COX-2) 의 발현 증가가 보고되고 있다. 그러나 연골 종양에서의 COX-2 발현에 대해서는 별로 알려진 바가 없다. 대상 및 방법: 내연골종 10예, 연골모세포종 11예, 연골점액양섬유종 5예, 통상적 연골육종 17예, 투명세포 연골육종 7예, 간엽성 연골육종 6예를 대상으로 COX-2에 대한 면역조직화학법을 시행하였다. 결과: 양성 연골 종양 중 연골모세포종 11예 중 6예(54.5%)에서 특징적인 강한 양성 반응을 나타내었다. 내연골종과 연골점액양섬유종은 단 1예를 제외하고는 모든 증례에서 음성이었다. 통상적인 연골육종에서 3예(17.6%)는 COX-2에 대해 강한 양성 반응을 보였는데 이러한 양성 증례는 모두 조직학적 등급 3의 분화가 나쁜 연골육종이었다. 투명세포 연골육종 중 2예(28.5%)는 국소적인 양성 반응을 나타내었고 모든 간엽성 연골육종은 음성이었다. 결론: 이러한 결과는 통상적인 연골육종에서 COX-2 과발현이 조직학적 등급 진행과 관계된 소견임을 시사한다. 연골모세포종의 COX-2 발현은 특별히 이 종양에 동반되는 종양 주변부의 염증성 변화를 유발하는 중요한 요소로 생각된다.

• ALGAE
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• 제19권3호
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• pp.153-160
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• 2004

The intergeneric relationship of Staurastrum complex including genus Arthrodesmus and Xanthidium was studied on the basis of mitochondrial coxⅢ sequence variation. Teiling's suggestion that Staurodesmus was an independent genus apart from genus Staurastrum, Arthrodesmus and Cosmarium was also reevaluated. The phylogeny inferred from coxⅢ gene was not consistent with morphological characteristics of Staurastrum complex. Genus Staurastrum was closely related to genus Xanthidium in the phylogenetic analysis of coxⅢ, but distant to genus Staurodesmus. The taxonomic treatment of genus Staurodesmus as an independent entity could not be determined, because Staurodesmus did not firm a monophyletic Glade. Therefore, genus Staurodesmus could not be treated as an independent genus as Prescott et al. (1982) claimed.

• Toxicological Research
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• 제17권
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• pp.89-96
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• 2001

Recently, considerable attention has been focused on the role of cyclooxygenase-2 (COX-2) in the carcinogenesis as well as in inflammation. Improperly overexpressed COX-2 has been observed in many types of human cancers and transformed cells in culture. Thus, it is conceivable that targeted inhibition of abnormally or improperly up-regulated COX-2 provides one of the most effective and promising strategies for cancer prevention. A ubiquitous eukaryotic transcription factor, NF-kB is considered to be involved in regulation of COX-2 expression. Furthermore, extracellular-regulated protein kinase and p38 mitogen-activated protein (MAP) kinase appear to be key elements of the intracellular signaling cascades involved in NF-kB activation in response to a wide array of external stimuli. Certain chemopreventive phytochemicals suppress activation of NF-kB by blocking one or more of the MAP kinases, which may contribute to their inhibitory effects on COX-2 induction. One of the plausible mechanisms by which chemopreventive phytochemicals inhibit NF-kB activation involves suppression of degradation of the inhibitory unit I kB, which hampers subsequent translocation of p65, the functionally active subunit of NF-kB.

• 한국농공학회지
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• 제32권E호
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• pp.20-32
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• 1990

Abstract This study was conducted to pursue the normalization of frequency distribution by making an approach to the coefficient of skewness to nearly zero through the Box-Cox transformation, to get probable flood flows can be calculated by means of the transformation equation which has been derivated by Box-Cox transformation in the annual maximum series of the applied watersheds. It has been concluded that Box-Cox transfromation is proved to be more efficient than logarithmic, square root and SMEMAX transformation which is based on the trigonometric solution of a right triangle whose three verteces repesent the smallest, median and largest observed values of a population in making the coefficient of skewness nearer to zero. Consequently it is shown that probable flood flows according to the return period based on Box-Cox transformation are closer to the observed data as compared to other methods including SMEMAX transformation and fitted probability distributions such as the three parameter lognormal and the type I extremal distribution for the applied watersheds.

• Journal of Chest Surgery
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• 제31권12호
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• pp.1230-1233
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• 1998

The Cox-Maze procedure was developed as a cure for atrial fibrillation. The recovery rate of both atrial contractility is reported low in the atrial fibrillation associated with mitral valvular heart disease than that of loan atrial fibrillation. We performed the Cox-Maze procedure (Maze III) in three cases who suffered from non-mitral heart diseases associated with atrial fibrillation: A ruptured sinus of Valsalva aneurysm, a ventricular septal defect, and an aortic stenoinsufficiency. The Cox-Maze procedure was performed concomitantly with correction of the underlying heart disease. Conversion to sinus rhythm was achieved in all three patients, and both right and left atrial mechanical activities could be identified echocardiographically after three postoperative months.

• ALGAE
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• 제18권3호
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• pp.199-205
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• 2003

It has been considered that genus Cosmarium including Staurastrum had the problems in grouping by morphological characters. Sequence data for the Cytochrome Oxidase subunit III (coxIII) were employed to compare with taxa of two divisions of this genus, with sections in each, for evaluating the taxonomic stability of these morphological characters. The division and section systems were not coincided with the phylogeny inferred from coxIII sequences, as the previous reports from us using nuclear rDNA ITS and chloroplast rbcL sequence comparisons in this genus. Two taxa of Staurastrum were not placed within a same clade each other, and one taxon of these was grouped in Arthrodesmus clade. Two genera, Cosmarium and Staurastrum, cannot be regarded as monophyletic from this result. Mitochondrial coxIII gene was considered as a useful phylogenetic tool to evaluate evolutionary relationships of desmids as in the case of land plants.