• 대한화학회지
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• 제57권1호
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• pp.88-93
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• 2013

In order to construct a controlled release system of drugs and to reduce toxic side effects of 5-fluorouracil, the novel ramose chitosan-based-5-fluorouracil microspheres (CS-FU-MS) were prepared. Firstly, using chitosan (CS) as carriers and 5-fluorouracil (5-FU) as a model drug, ramose chitosan-based-5-fluorouracil (CS-FU) was efciently synthesized by chemical crosslinking method through microwave irradiation, drug loading was 10.6%; Secondly, CS-FU-MS were prepared by CS-FU self-assembled under the dialysis conditions and the free 5-FU was encapsulated further at the same time. The size dispersivity of particles is uniform, and the average diameter of the CS-FU-MS was $4{\mu}m$. The drug encapsulation efficiency was 76.1%, and the drug loading was increased to 26.22%. CS-FU-MS maintain the zero-order release time in PBS (pH = 7.4) and HCl/KCl (pH = 1.2) dialysis medium was 40h and 34h respectively, and the cumulative release were 58.89% and 79.33% in 182 h. The results showed that CS-FU-MS have excellent sustained release properties.

• 대한화학회지
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• 제56권4호
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• pp.473-477
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• 2012

The novel chitosan-based thermosensitive hydrogels were prepared as control-releasing drug carriers. N-carboxyethyl chitosan (ACS) was synthesized by microwave heating for 1 h through Michael addition of CS to acrylic acid in a grafting yield of 52.97%, which was proved to be a faster and more efficient way than ordinary methods. 5-Fu was modified with formaldehyde to synthesize N,N'-Bis(hydroxymethyl)-5-fluorouracil (5-Fu-OH). Then an esterification was performed using ACS and 5-Fu-OH to give 5-Fu-ACS. The new thermosensitive hydrogels were prepared by adding sodium glycerophosphate to the solution of compounds under a certain constant temperature. Simultaneously, the hydrogels' swelling rate, in vitro drug release rate and thermosensitive were studied, and found that the 5-Fu-ACS composite hydrogel had more excellent releasing effect, higher drug loading and better thermosensitive.

• 한국철학논집
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• 제43호
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• pp.295-317
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• 2014

본 논문은 송대 도학가들이 "논어(論語)"에 나온 "극기복례(克己復禮)"의 "극기(克己)"를 "사욕의 제거"로 풀이한 이유는 무엇일까에 관한 문제를 다룬다. 주지하듯, "극기복례(克己復禮)"는 공자가 "인(仁)"을 실천하는 방법으로 제시한 구절이다. 따라서 본 논문에서는 이 문제가 "인(仁)"에 관한 송대 도학가들의 해석과 깊은 관련이 있다고 보고, 송대 도학가들의 "인(仁)" 개념 풀이를 살펴보았다. 송대 도학가들은 "인(仁)"을 "천리(天理)"로 풀이하였으며, 천리의 내용을 "만물을 생성하는 마음(天地生物之心)"으로 보았다. 주희는 주역의 "생생(生生)" 및 도가의 "허(虛)", "유(柔)" 등의 개념을 연결하여, 이정(二程) 및 그 후학들이 새롭게 제기한 인(仁)의 해석과 극기복례(克己復禮)의 해석에 철학적 설명을 제공하였다. 주희가 도가를 맹렬히 비판한 것은 사실이나, 도가의 사상에서 전혀 취할 바가 없다고 생각하지는 않았다. 본 논문에서 제시한 "사욕의 제거(去私欲)"에 관한 주희 및 송대 도학가들의 입장 역시 이러한 주장을 뒷받침해주는 논거가 될 수 있을 것이다.

• 한국철학논집
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• 제37호
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• pp.159-195
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• 2013

주희와 육구연 간의 논쟁은 송명이학의 전개 과정에 있어 가장 중요한 학술논쟁이자 주희의 학술 생애 중 가장 격렬했던 논쟁 가운데 하나였다. 양자 간의 사상적인 이견(異見)으로 인해 전개된 논쟁은 그들이 생존해 있을 때에는 다만 학문 방법론을 둘러싸고 벌어진 논쟁이었다고 한다면, 그들 사후 이로 말미암아 전개된 것은 양대 학술 유파 간의 분쟁이라 할 수 있다. 송 원 명대를 거쳐 학술계에서 지속적으로 진행되어 온 주륙이동논쟁은 주희 사상의 변화를 고증하는 문제에 있어 적절한 대응을 하지 못하였으니, 이로 말미암아 학자들은 육자의 사상을 제대로 알지 못하였을 뿐 아니라 주자의 사상 역시 제대로 파악할 수가 없었다. 그리하여 청대에 이르러 이 방면에 대한 연구가 더욱 심화되었고, 각각의 주장을 대표하는 인물들과 문장들이 무수히 쏟아져 나오게 되었다. 청대의 육왕학자인 이불은 "주자만년전론"을 통해 비교적 객관적인 입장에서 주자와 육구연의 사상을 비교 검토하고 있다. "주자만년전론"이 비록 육왕학의 입장을 옹호하기 위해서 쓰여진 면이 없지 않지만, 주륙 사상에 대한 비교 작업이 객관적인 고증학적 작업을 통해서 수행되었다는 점이다. 이불의 주륙관은 육왕학을 기본 토대로 하여 주자학을 수용하고 있으며, 이를 통해 주륙 사상의 조화를 꾀하고자 하였다. 이러한 입장에서 이불은 육왕학에 대해서도 무비판적으로 수용하기보다는 육왕학에 대해 선별 취사하여 새로운 해석을 가하고 있다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7611-7615
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• 2014

Aims: To prepare 5-fluorouracil (5-Fu) nanoparticles with higher encapsulation efficiency and drug loading, and then investigate interaction with the SGC-7901 gastric cancer cell line. Materials and Methods: Prescription was optimized by orthogonal experiments, the encapsulation efficiency and loading capacity were tested by high-performance liquid chromatography, and inhibition of proliferation by 5-Fu nanoparticles and 5-Fu given to cells for 24, 48 and 72 hours was investigated by methyl thiazolyl tetrazolium assay (MTT). In addition, 5-Fu nanoparticles were labeled by fluorescein isothiocyanate (FITC), and absorption into cells was tested by flow cytometry. Results: The optimal conditions for preparation were concentrations of 5-Fu of 5mg/ml, of $CaCl_2$ of 60 mg/ml and of chitosan of 2 mg/ml. With a stirring speed of 1200rpm, encapsulation efficiency of 5-Fu nanoparticles was $55.4{\pm}1.10%$ and loading capacity was $4.22{\pm}0.14%$; gastric cancer cells were significantly inhibited by 5-Fu nanoparticles in a time and concentration dependent manner, and compared to 5-Fu with slower drug release, in a certain concentration range, inhibition with 5-Fu nanoparticles was stronger. 5-Fu nanoparticles were absorbed by the cells in line with the concentration. Conclusions: 5-Fu nanoparticles can inhibit growth of gastric cancer cells in vitro to a greater extent than with 5-Fu with good adsorption characteristics, supporting feasibility as a carrier.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 12th Asian Congress of Fluid Mechanics
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• pp.35.5-35.5
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• 2008

• Asian Pacific Journal of Cancer Prevention
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• 제13권9호
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• pp.4807-4814
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• 2012

Purpose: The chemoresistance of human hepatocellular carcinoma (HCC) to cytotoxic drugs, especially intrinsic or acquired multidrug resistance (MDR), still remains a major challenge in the management of HCC. In the present study, possible mechanisms involved in MDR of HCC were identified using a 5-fluorouracil (5-FU)-resistant human HCC cell line. Methods: BEL-7402/5-FU cells were established through continuous culturing parental BEL-7402 cells, imitating the pattern of chemotherapy clinically. Growth curves and chemosensitivity to cytotoxic drugs were determined by MTT assay. Doubling times, colony formation and adherence rates were calculated after cell counting. Morphological alteration, karyotype morphology, and untrastructure were assessed under optical and electron microscopes. The distribution in the cell cycle and drug efflux pump activity were measured by flow cytometry. Furthermore, expression of potential genes involved in MDR of BEL-7402/5-FU cells were detected by immunocytochemistry. Results: Compared to its parental cells, BEL-7402/5-FU cells had a prolonged doubling time, a lower mitotic index, colony efficiency and adhesive ability, and a decreased drug efflux pump activity. The resistant cells tended to grow in clusters and apparent changes of ultrastructures occurred. BEL-7402/5-FU cells presented with an increased proportion in S and G2/M phases with a concomitant decrease in G0/G1 phase. The MDR phenotype of BEL-7402/5-FU might be partly attributed to increased drug efflux pump activity via multidrug resistance protein 1 (MRP1), overexpression of thymidylate synthase (TS), resistance to apoptosis by augmentation of the Bcl-xl/Bax ratio, and intracellular adhesion medicated by E-cadherin (E-cad). P-glycoprotein (P-gp) might play a limited role in the MDR of BEL-7402/5-FU. Conclusion: Increased activity or expression of MRP1, Bcl-xl, TS, and E-cad appear to be involved in the MDR mechanism of BEL-7402/5-FU.

• 한국의류학회지
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• 제18권4호
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• pp.566-573
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• 1994

The Purpose of this study is to the organization principles of mourning dresses in Confucianism. The results of this thesis summarised as follow: The organization of mourning dresses laying stress on LiGi, the book of rites has six kinds of contents, Fushu. It is established on the rules and regulations of a religious sect in Confucianism, ZongFa. The succession ideology of ZongFaism has played on important parts in formation and conservation of the large familly system by the medium of mourning dresses with 5 classified costumes, WuFu. And the familly system in mourning dresses makes the rules in kindship category and primogeniture by WuFu grades.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.106-107
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• 2006

A series of vinyl monomers and their saturated model compounds containing different chromophores were synthesized. These monomers display strong intra-molecular fluorescence quenching, their fluorescence quantum yields and lifetimes are generally lower than those of their model compounds. It was found that the C=C bonds in these monomers played a key role in the intra-molecular quenching, which was confirmed by intermolecular fluorescence quenching and time-resolved fluorescence studies. On the basis of the intra-molecular quenching, a new fluorescence approach can be developed to monitor the process of the polymerization and curing of bismaleimides, which can directly reflect the C=C bond consumption during polymerization and curing.

• The Korean Journal of Pain
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• 제36권4호
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• pp.473-475
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• 2023