• Title/Summary/Keyword: PAF model

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Screening of PAF Antagonists from Medicinal Plants (수종의 생약으로부터 혈소판활성화인자 (PAF) 길항제 검색)

  • 손건호;김소희;정근영;장현욱
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1994.04a
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    • pp.249-249
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    • 1994
  • PAF (Platelet-activating factor: 혈소판 활성화인자)는 1972년 Benveniste등에 의해 토끼의 호중구 배양 상청액중에서 발견되어 1979년 그 구조가 1-alkyl-2-acethyl-sn glycero-3-phosphocholine의 구조를 갖는 에테르형 인 지질임이 밝혀졌다. 그후 혈소판 이외 과립구, 단구나 macrophage, 혈관내피세포등 조직의 염증담당세포가 다양한 자극에 응하여 PAF를 생성됨이 보고되었다. PAF가 나타내는 대표적 활성으로는 혈소판, 호중구, 단구들의 활성화, 호중구의 유주 활성, 혈관투과성 항진, 혈압강하작용. 기관지 수축 등이 알려졌으며. 또한 염증, 알러지, 천식 endotoxin shock 등 여러질병에 직·간접적으로 관여함이 알려졌다. 이와같은 여러 생리 현상은 PAF의 특이적수용체를 개재하여 일어난다는 것이 밝혀졌다. 따라서 PAF의 다양한 질병의 관여가 밝혀짐으로서, PAF길항제의 개발이 활발히 진행되어왔다. 지금까지 PAF길항제의 개발은 PAF 구조 유사체. benzodiazepam유도체, thiazole유도체 등과 같은 합성품과 ginkolide, kadsurenone과 같은 천연물 유리의 것이 알려져 in vivo model에서도 그 효능이 확인되었다. 본 연구는 이와 같은 배경에서 20여 종의 생약에서 PAF 길항제를 검색하던 중 5종류의 생약에서 PAF 길항작용을 갖는 분획을 찾았기에 이에 보고한다.

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Effect of Platelet-Activating Factor (PAF) on Murine Ovulation, Early Embryo Development and Implantation (Platelet-Activating Factor (PAF)가 생쥐의 배란, 초기배아의 발달 및 착상에 미치는 영향)

  • Kang, Kil-Chun;Lee, Young-Il
    • Clinical and Experimental Reproductive Medicine
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    • v.18 no.2
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    • pp.143-151
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    • 1991
  • An embryo-derived platelet activating factor (PAF) has been demonstrated to play an important role in reproduction. This report examined the effect of PAF on ovulation, fertilization, embryo development, implantation and fetal viability by using murine model. PAF had no stimulatory effect on ovulation and fertilization. But PAF had stimulatory effect on embryo development in in-vitro test, in spite of no effect on implantation and fetal viability. These results demonstrate that exogenous PAF could enhance embryo development and implantation and give suggestion that PAF may play an role in human IVF program.

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Role of Nuclear Factor (NF)-κB Activation in Tumor Growth and Metastasis (종양의 성장 및 전이에 있어서 NF-κB의 역할)

  • Ko, Hyun-Mi;Choi, Jung-Hwa;Ra, Myung-Suk;Im, Suhn-Young
    • IMMUNE NETWORK
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    • v.3 no.1
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    • pp.38-46
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    • 2003
  • Background: Platelet-activating factor (PAF) induces nuclear factor $(NF)-{\kappa}B$ activation and angiogenesis and increases tumor growth and pulmonary tumor metastasis in vivo. The role of $NF-{\kappa}B$ activation in PAF-induced angiogenesis in a mouse model of Matrigel implantation, and in PAF-mediated pulmonary tumor metastasis were investigated. Methods: Angiogenesis using Matrigel and experimental pulmonary tumor metastasis were tested in a mouse model. Electrophoretic mobility shift assay was done for the assessment of $NF-{\kappa}B$ translocation to the nucleus. Expression of angiogenic factors, such as tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\alpha}$, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were tested by RT-PCR and ELISA. Results: PAF induced a dose- and time-dependent angiogenic response. PAF-induced angiogenesis was significantly blocked by PAF antagonist, CV6209, and inhibitors of $NF-{\kappa}B$ expression or action, including antisense oligonucleotides to p65 subunit of $NF-{\kappa}B$ (p65 AS) and antioxidants such as ${\alpha}$-tocopherol and N-acetyl-L-cysteine. In vitro, PAF activated the transcription factor, $NF-{\kappa}B$ and induced mRNA expression of $TNF-{\alpha}$, $IL-1{\alpha}$, bFGF, VEGF, and its receptor, KDR. The PAF-induced expression of the above mentioned factors was inhibited by p65 AS or antioxidants. Also, protein synthesis of VEGF was increased by PAF and inhibited by p65 AS or antioxidants. The angiogenic effect of PAF was blocked when anti-VEGF antibodies was treated or antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF was co-administrated, but not by antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF each alone. PAF-augmented pulmonary tumor metastasis was inhibited by p65 AS or antioxidants. Conclusion: These data indicate that PAF increases angiogenesis and pulmonary tumor metastasis through $NF-{\kappa}B$ activation and expression of $NF-{\kappa}B$-dependent angiogenic factors.

A Case Study on the Quality Costs in a ICT Industry (ICT 산업의 품질비용 연구 사례)

  • Hwang, Gee-Hyun
    • Journal of Korean Society for Quality Management
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    • v.40 no.2
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    • pp.106-116
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    • 2012
  • This paper aims to develop the adequate quality cost model at a company which delivers ICT(information communication technology) services. One particular business unit was in the first instance selected and quality costs were then analysed at an organization level, for a department and for specific processes. Some areas were determined for quality improvement at each level and their causes were also investigated. However, the existing PAF(prevention, appraisal and failure) models reveled some limitations because the ICT services company included the different number of large and complicated business processes. The PAF model did not sufficiently highlight the detailed causes of failure costs. It did not also stimulate the relevant department's strong responsibility to improve such problems. Both micro PAF and process cost models were proposed in order to cope with this. In final, it explains the relationship between six sigma and quality costing, suggesting how to use the quality costing results as a means of promoting either continuous improvement or innovation in a case company.

A Research on the Development of Quality Cost Management System for Power Industry (발전산업의 품질비용 관리체계 구축에 관한 연구)

  • Lee, Myong Chang;Hwang, Bong Sun;Park, Sang Jun;Kim, Min Gyu;Kim, Dong Chun;Shin, Wan Seon
    • Journal of Korean Society for Quality Management
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    • v.44 no.4
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    • pp.713-733
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    • 2016
  • Purpose: The primary objective of this case study is to establish a COQ(Cost of Quality) management system for power generation industries. Key topics of this study include collecting COQ elements, their classifications, COQ computation formula, and determining COQ improvement projects. Results: A comprehensive set of COQ elements have been isolated for electric power generation companies. The COQ elements were classified in such a way that they could be managed according to the PAF model as well as the SIPOC diagram. This study showed that a systematic approach could be established for monitoring the COQ elements and using them in the process of improving quality competitiveness. Methods: The PAF(Prevention-Appraisal-Failure) model has been employed in the process of collecting COQ elements for a power generation company. All the cost of quality elements were first examined through an extensive review of articles and books in the field of quality. The cost elements were then refined and augmented by conducting a comparative study with international standards. The COQ elements have been verified by a group of quality managers and classified according to both the PAF model and the SIPOC diagram for better understanding in the entire organization. An improvement strategy has been also proposed by using a typical COQ level of power generation companies. Conclusion: The conventional PAF model was used in establishing a COQ management system for power generation industries. This case study illustrates the procedure about identification, classification and computation of quality costs, including selection of improvement projects. The system can be used not only for observing the current state of cost elements related to quality, but also for planning an improvement strategy using the ratio of cost classification.

Effects of cyclopiazonic acid and aflatoxin B1 on rabbit platelet aggregation and ATP release (Cyclopiazonic acid 및 aflatoxin B1이 토끼의 혈소판 응집 및 ATP 방출에 미치는 영향)

  • Hong, Choong-man;Cho, Myung-haing
    • Korean Journal of Veterinary Research
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    • v.36 no.4
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    • pp.887-894
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    • 1996
  • Cyclopiazonic acid(CPA) known as stimulating the release of intracellular calcium, aflatoxin $B_1(AFB_1)$ causing gastrointestinal hemorrhage frequently were used as model toxic mycotoxins in these studies. First of all, the effects of various mycotoxins on the platelet aggregation response were determined. The effects of mycotoxins on the ATP release from platelet by aggregating factors were investigated. The results and conclusions obtained from these studies are : 1) CPA promoted ADP, collagen, thrombin, A.A. and PAF-induced rabbit platelet aggregation. $AFB_1$ inhibited collagen, A.A. and PAF-induced rabbit platelet aggregation only. 2) CPA increased both aggregation and disaggregation time, whereas $AFB_1$ decreased in a dose dependent manner. 3) CPA increased ADP, thrombin, A.A. and PAF-induced ATP release. $AFB_1$ increased A.A.-induced ATP release and decreased PAF-induced release in a dose dependent manner. In conclusion, CPA promoted platelet aggregation by the increase of ATP. Antiaggregating effects of AFB1 may be due to decreases of ATP. These data provide the basis for the future study of roles of ATP release in platelet aggregation.

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Effect of Plantaginis asiaticae Folium water extract on body fat loss in high fat-induced obese C57BL/6 mice (차전초 잎의 물 추출물이 고지방식이로 비만 유도된 C57BL/6 생쥐의 체지방 감소에 미치는 영향)

  • Kim, So Young;Jeong, Mi Jin;Kim, Yoo Jin;Lee, Un-Tak;Choo, Sung-Tae;Kim, Han-Hyuk;Kim, Mi Ryeo
    • The Korea Journal of Herbology
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    • v.33 no.2
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    • pp.59-67
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    • 2018
  • Objective : Plantago asiatica L. has been used for many years in Korea, China, and Japan for the treatment of many diseases such as anti-inflammatory, anti-asthma and diuretic. But the anti-obesity effect of Plantaginis asiaticae Folium has not been studied yet. Thus, this study aimed to demonstrate the anti-obesity efficacy of Plantaginis asiaticae Folium water extract (PAF) in high fat diet-induced obesity animal model. Method : Male, five-weeks old C57BL/6 mice were divided into 5 groups; ND (normal diet + 0.9% saline), HFD (high-fat diet + 0.9% saline), PC (high-fat diet + Garcinia cambogia 500 mg/kg), PAF 100, 300 (high-fat diet + PAF 100, 300 mg/kg. Treatments were performed daily for 6 weeks per os. We evaluated the changes of body weight, white adipose tissues weight, hepatic and fecal lipids level, pancreatic lipase activity and lipid profiles in plasma. Result : Body weights, adipose tissue weights and FER were significantly lower in mice fed the high-fat diet with PAF treatment than in mice fed the high-fat diet alone. In plasma, TG, TC, LDL-C, ATS and ALT levels significantly decreased in PAF groups compared with HFD group. Also, hepatic triglyceride (TG) levels decreased and fecal TG increased in PAF groups compared to HFD group. In addition, the activity of pancreatic lipase was decreased in the PAF groups compared to that of HFD group. Conclusion: These results suggest PAF extract is effective in preventing and improvement obesity, so it might be a potential and safe material for anti-obesity agent of weight control or functional supplements.

Development of Quality Cost Measurement Items in Service Industry (서비스산업에서의 품질비용 측정 항목 도출에 관한 연구)

  • Lee, Maeng-Jeon;Park, Jung-Oun;Chung, Young-Bae
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.35 no.3
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    • pp.148-154
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    • 2012
  • The purpose of this study is to develop measurement items for quality cost in service industries. Quality cost is necessary in order to evaluate quality management activities. It is clear that the quality cost in service industry is different from manufacturing industry. Generally, in service industries, quality cost is very difficult to assess because it has a unique characteristics. This paper proposes an effective method for measuring quality cost in service industries. Based on the PAF (Prevention, Appraisal, Failure) cost model, we utilizes the concept of five demensions in SERVQUAL which are tangibles, reliability, responsiveness, assurance, empathy. This paper also presents to a standard model for quality cost measurement in service industries.

A Simulation Model for the protein Deposition of Pigs According to Amino Acid Composition of Feed Proteins (사료의 아미노산 조성에 따른 돼지의 단백질 축적을 나타내는 수치모델)

  • 이옥희;김강성
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.28 no.1
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    • pp.178-190
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    • 1999
  • This study was conducted to develop a simulation model for the growth dynamics of pigs and to describe quantitatively protein deposition depending on the amino acid composition of feed protein. In the model it is assumed that the essential processes that determine the utilization of feed protein in the whole body are protein synthesis, breakdown of protein, and oxidation of amino acid. Besides, it is also assumed that occurrence of protein deposition depends on genetic potential and amino acid composition of feed protein. The genetic potential for the protein deposition is the maximum capacity of protein synthesis, being dependent on the protein mass of the whole body. To describe the effect of amino acid composition of feed on the protein deposition, a factor, which consist of ten amino acid functions and lie between 0 and 1, is introduced. Accordingly a model was developed, which is described with 15 flux equations and 11 differential equations and is composed of two compartments. The model describes non linear structure of the protein utilization system of an organism, which is in non steady state. The objective function for the simulation was protein deposition(g/day) cal culated according to the empirical model, PAF(product of amino acid functions) of Menke. The mean of relative difference between the simulated protein deposition and PAF calculated values, lied in a range of 11.8%. The simulated protein synthesis and breakdown rates(g/day) in the whole body showed a parallel behavior in the course of growth.

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Application of Time-Driven Activity-Based Costing(TDABC) for Total Productive Maintenance(TPM) and Cost of Quality(COQ) Processes (TPM과 COQ 프로세스에서 시간동인 ABC시스템의 활용)

  • Choi, Sungwoon
    • Journal of the Korea Safety Management & Science
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    • v.17 no.1
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    • pp.321-335
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    • 2015
  • This study introduces the methods to apply and develop the integrated Cost of Quality (COQ) and Time-Driven Activity-Based Costing (TDABC) model for seeking not only quality improvement but also reduction of overhead cost. Inefficient and uneconomical COQ activities can be identified by using time driver which also maximizes the quality improvement for Prevention-Appraisal- Failure (PAF) quality costs. In contrast, reduction of the indirect cost of unused capacity resource using Quality Cost Capacity Ratio (QCCR) of TDABC minimizes overhead cost for COQ activities. In addition, linkage between Overall Equipment Effective (OEE) and Time Driver develops the integrated system of Total Productive Maintenance (TPM) and TDABC model. Lean OEE maximizes when an Unused Time (UT) of TDABC that are TPM losses and lean wastes reduces whereas the TPM Cost Capacity Ratio (TCCR) of TDABC minimizes indirect cost for non-value added TPM activities. Numerical examples are derived to better understand the proposed COQ/TDABC model and TPM/TDABC model from this paper. From the proposed model, process mapping and time driver of TDABC are known to lessen indirect cost from general ledger of comprehensive income statement with a better quality innovation and improvement of equipment.