암 세포의 대식세포 콜로니 자극인자를 통한 골수성 세포의 지방산합성효소 및 PPARβ/δ 핵수용체 활성화에 따른 종양 성장의 기전

학위논문 (박사)-- 서울대학교 대학원 : 의과대학 의과학과, 2016. 2. 김효수.Introduction: Tumor myeloid cells have a central role in tumor progression. However, the mechanism by which the myeloid cells sense the tumor microenvironment and activate their pro-tumoral function remains unclear. Methods: Lewis lung carcinoma tumor model with PPARβ/δ-deficient bone marrow transplantation and adoptive transfer of wild-type macrophages were used to study the role of myeloid PPARβ/δ in tumor progression. Results: PPARβ/δ is strongly expressed and activated in tumor myeloid cells. PPARβ/δ promotes tumor growth and angiogenesis by inducing pro-tumoral phenotype of myeloid cells. This pro-tumoral phenotype, represented as IL-10 expression, stimulates tumor cell invasion and angiogenesis apart from its well-known immune regulatory function. Conclusions: The activation of PPARβ/δ in myeloid cell is dependent on increased fatty acid synthase expression, which is augmented by cancer cell derived cytokine, M-CSF.General Introduction 1 Chapter 1 PPARβ/δ in myeloid cells and tumor progression 3 Introduction 4 Material and Methods 5 Results 16 Discussion 31 Chapter 2 Dissecting the mechanism of PPARβ/δ mediated pro-tumoral myeloid cell activation 34 Introduction 35 Material and Methods 37 Results 45 Discussion 64 References 71 Abstract in Korean 82Docto

Econometric models with nonstationary time series

Thesis (doctoral)--서울대학교 대학원 :국제경제학과 경제학전공,2000.Docto

광섬유 광학 시스템의 성능 향상을 위한 라만 증폭의 응용에 관한 연구

Thesis(doctor`s)--서울대학교 대학원 :전기·컴퓨터공학부,2007.Docto

Performance analysis of parallel execution of X.264 encoder on the cell processor

학위논문(석사)--서울대학교 대학원 :전기·컴퓨터공학부,2007.Maste

Effects of psychotropic agents and ethanol on secretory function of the stomach

의학과/박사[한글] 스트레스는 실험동물 및 인체에서 위산분비를 촉진하고 위궤양발생을 증가시킨다는 사실은 널리 알려져 있다. 그리고 그 경로는 미주신경을 경유하기도 하고 또 일부는 ACTH를 유리시키기 때문이라고 한다. 향정신성약물은 위산분비를 감소시키고 위궤양발생을 억제시킨다고 알려져 있다(Sun 및 Shay 1959, Dasgupta 및 Mukherjee 1967). 그러나 reserpine은 이와 달리 위산분비를 증가시키고 위궤양을 유발시킨다. 알콜은 많은 하자들에 의해서 위산분비를 자극하는 것으로 알려져 왔으나 근래 일부 학자들은 오히려 억제한다고 주장하면서 그에 대한 기전을 여러 각도에서 설명하려하고 있다(Puurunen 1978, Shanbour등 1973, Sernka 1974). 본 실험에서는 reserpine, haloperidol, chlorpromazine및 diazepam이 스트레스를 받고 있는 흰쥐의 위 분비기능과 궤양발생에 미치는 영향을 추구하였고 또 ethanol을 복강내주사, 경구투여, 위 관류, 위 및 장내 직접 적용등 여러가지 방법으로 처치하여서 위 분비기능과 궤양발생에 미치는 영향을 검토하였다. 실험동물로는 200g 내외의 흰쥐를 사용하였다. 향정신성약물 투여군은 diazepam(1.25ma/kg I,p.), chlorpromagine(10mg/kg i.p.), haloperidol(1mg/kg i.p.), reserpine(0.1mg/kg i.p.)를 투여하였고 ethanol투여군은 복강내주사(1.5g/kg), 경구투여(20%), 위 관류(10% 혹은 20%, 4ml/5min.), 위 혹은 장내 직접 적용(10% 혹은 20%, 1ml) 등의 방법으로 처치하였다. 스트레스궤양 발생은 Robert 및 Nezamis의 방법에 따라 궤양지수를 산출했고 분비된 위액의 채취는 Shay등의 방법을 사용하였다. Ethanol 위 관류군은 urethane으로, 그외 실험군은 ether로 마취하였다. 실험 성적을 요약하면 다음과 같다. 1. 위 분비기능은 chlorpromazine, haloperidol 단회 투여로 현저히 억제되었고 반복 투여로 억제 효과의 감소를 초래하였다. 그러나 reserpine과 diazepam의 위액분비 및 위산분비기능에 대한 영향은 크지 않았다. 2. 알콜은 복강내주사와, 경구투여, 위 관류, 위 혹은 장내 직접 투여 등 투여경로에 관계없이 모두 위 분비기능을 현저히 억제하여 위액분비 및 산분비의 감소와 pH의 상승을 나타냈다. 3. 위궤양발생은 약물 전처치 기간에 관계없이 chlorpromazine, halorperidol, ethanol 전처치군에서 현저히 억제되나 reserpine 처치로는 궤양발생의 증가 경향을 나타냈으며 diazepam처치군은 대조군과 비슷한 양상을 보였다. 이상의 결과를 종합하여 보면 위 분비기능에 대한 향정신성약물의 영향은 비교적 크고 특히 chlorpromazine, haloperidol 및 알콜은 위기능 억제작용과 위궤양발생 억제효과가 현저함을 인지하는 바이다. [영문] It is Widely accepted that stress could enhance acid secretion and ulceration of stomach in animal and man. The mechanism of ulceration due to stress has been explained through vagal stimulation and release of ACTH. Recently it was been known that psychotropic agents act as inhibitors in acid secretion and ulceration induced by stress(Sun & Shay 1959, Dasgupta & Mu-kherjee 1967). Reserpine, one of classical psychotropic agents, however, enhances gastric acid secretion and it is also able to provoke gastric ulceration. Traditionally alcohol was been thought as a stimulant of acid secretion in stomach. Recently some investigators insist that alcohol has an inhibitory effect on gastric acid secretion and the possible mechanisms are explored (Puurunen 1978, Shanbour et al 1973, Sernka et at 1974). In the present study, effects of reserpine, haloperidol, chlorpromazine and diazepam on acid secretion and ulceration of murine stomach under The restraint stress were investigated. Also the effect of ethanol was studied on the secretory function and ulceration of the stomach following administration through various routes, eg. intraperitoneal injection, per os administration, gastric perfusion, and direct application into the stomach or intestinal lumen. The experiments were performed on rats weighing about 200g under ether or urethane(1.2g/kg, S.Q.) anesthesia. Drugs used were diazepam(1.25mg/kg, i.p.), chlorpromazine(10mg/kg, i.p.), haloperidol(1mg/kg, i.p.), reserpine(0.1mg/kg, i.p.) and ethanol (1.5g/kg, i.p.:20% p.o.). Gastric perfusion was performed wish 4 ml of 10% or 20% solution/5 mins. and direct application of 1ml Of 10% or 20% solution into the gastric or duodenal lumen. The results are summarized as follows, 1. Secretory function of the stomach was significantly inhibited by single administration of chlorpromazine or haloperidol, while repeated administration of the psychotropics resulted in diminishing the effectiveness. The effect of reserpine or diazepam on volume and acidity of the gastric juice was not remarkable. 2. Alcohol inhibited the secretory function of the stomach sigificantly, which resulting in decrease in volume and acidity of the gastric juice, and increase in pH. These effects had not differed by the route of administration. 3. Development of stress ulcer was significantly inhibited in the animals given chlorpromazine, haloperidol or ethanol prior to the experiment. In the reserpine treated group the ulceration rate was slightly increased. The influence of diazepam baa the least and similar as to the control group. The occurance of ulcers had not been affected by prior chronic treatment. From the above results, it is concluded that effects of paychotropic agents with single administration on the gastric function are apparently marked. Particularily the inhibitory effects of chlorpromazine, haloperidol and alcohol on gastric secretion and their preventive effects on gastric ulceration are significant.restrictio

반복 구매를 위한 효과적인 경매 메커니즘 설계

학위논문(박사) - 한국과학기술원 : 경영공학전공, 2009. 8., [ vi, 91 p. ]Repetition is one of the key aspects of emerging business procurement auctions. However, very little research has been done about the characteristics of repeated auctions and the design of auction mechanisms suitable for the repeated procurements. Sustainable auction mechanisms for repeated procurement need to enable the auctioneer to gain price advantages by maintaining a sufficient number of bidders over time. For this purpose, we propose the Memory Augmented Auction (MAA) mechanism, which considers not only current bid prices, but also memory scores based on previous bid price competitiveness along with the winning rate. Under the MAA mechanism, beneficial bidders will have a better chance of winning, thus gaining motivation to join the auction market. From the empirical analysis on repeated auction data from iMarketKorea’s (IMK) MRO items, we found a substantial benefit of the MAA. Among the top 25 MRO items which occupies 77% of auctions, 5 items have significantly decreasing pattern in terms of number of bidders per auction over time. In addition, the average of successful auction rate of 11 items is as low as 70%. Thus, 16 out of 25 items that covers 43% of MRO auctions at IMK suffers from the insufficient number of participating bidders particularly after a certain number of iterations. This phenomenon demonstrates the potential benefit of the MAA approach. Furthermore, we analyzed the bidder’s bid price determination model based on the collectable data in the auction market so that we can imitate the bid pricing agents for the experiment. By applying the MAA to the B2B procurement portal site, we aim to demonstrate the decreased purchase cost and increased auction success rate. For this purpose, we implemented the MAA mechanism and conducted a comprehensive performance evaluation by comparing the performance of MAA and Traditional Auction (TA) mechanisms. We confirmed that MAA outperforms for all the goals - purchase cost, number of remaining bi...한국과학기술원 : 경영공학전공