• Title/Summary/Keyword: agent model

Search Result 1,682, Processing Time 0.033 seconds

A Simple Dosing Scheme for Intravenous Busulfan Based on Retrospective Population Pharmacokinetic Analysis in Korean Patients

  • Choe, Sang-Min;Kim, Gayeong;Lim, Hyeong-Seok;Cho, Sang-Heon;Ghim, Jong-Lyul;Jung, Jin-Ah;Kim, Un-Jib;Noh, Gyu-Jeong;Bae, Kyun-Seop;Lee, Dong-Ho
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.16 no.4
    • /
    • pp.273-279
    • /
    • 2012
  • Busulfan is an antineoplastic agent with a narrow therapeutic window. A post-hoc population pharmacokinetic analysis of a prospective randomized trial for comparison of four-times daily versus once-daily intravenous busulfan was carried out to search for predictive factors of intravenous busulfan (iBu) pharmacokinetics (PK). In this study the population PK of iBu was characterized to provide suitable dosing recommendations. Patients were randomized to receive iBu, either as 0.8 mg/kg every 6 h or 3.2 mg/kg daily over 4 days prior to hematopoietic stem cell transplantation. In total, 295 busulfan concentrations were analyzed with NONMEM. Actual body weight and sex were significant covariates affecting the PK of iBu. Sixty patients were included in the study (all Korean; 23 women, 37 men; mean [SD] age, 36.5 [10.9] years; weight, 66.5 [11.3] kg). Population estimates for a typical patient weighing 65 kg were: clearance (CL) 7.6 l/h and volume of distribution (Vd) 32.2 l for men and 29.1 L for women. Inter-individual random variabilities of CL and $V_d$ were 16% and 9%. Based on a CL estimate from the final PK model, a simple dosage scheme to achieve the target $AUC_{0-inf}$ (defined as median AUC0-inf with a once-daily dosage) of 26.18 $mg/l{\cdot}hr$, was proposed: $24.79{\cdot}ABW^{0.5}mg$ q24h, where ABW represents the actual body weight in kilograms. The dosing scheme reduced the unexplained interindividual variabilities of CL and Vd of iBu with ABW being a significant covariate affecting clearance of iBU. We propose a new simple dosing scheme for iBu based only on ABW.

Tumorigenic Effects of Endocrine-disrupting Chemicals are Alleviated by Licorice (Glycyrrhiza glabra) Root Extract through Suppression of AhR Expression in Mammalian Cells

  • Chu, Xiao Ting;de la Cruz, Joseph;Hwang, Seong Gu;Hong, Heeok
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.12
    • /
    • pp.4809-4813
    • /
    • 2014
  • Endocrine-disrupting chemicals (EDCs) have been reported to interfere with estrogen signaling. Exposure to these chemicals decreases the immune response and causes a wide range of diseases in animals and humans. Recently, many studies showed that licorice (Glycyrrhiza glabra) root extract (LRE) commonly called "gamcho" in Korea exhibits antioxidative, chemoprotective, and detoxifying properties. This study aimed to investigate the mechanism of action of LRE and to determine if and how LRE can alleviate the toxicity of EDCs. LRE was prepared by vacuum evaporation and freeze-drying after homogenization of licorice root powder that was soaked in 80% ethanol for 72 h. We used 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as a representative EDC, which is known to induce tumors or cancers; MCF-7 breast cancer cells, used as a tumor model, were treated with TCDD and various concentrations of LRE (0, 50, 100, 200, $400{\mu}g/mL$) for 24, 48, and 72 h. As a result, TCDD stimulated MCF-7 cell proliferation, but LRE significantly inhibited TCDD-induced MCF-7 cell proliferation in a dose- and time-dependent manner. The expression of TCDD toxicity-related genes, i.e., aryl hydrocarbon receptor (AhR), AhR nuclear translocator, and cytochrome P450 1A1, was also down-regulated by LRE in a dose-dependent manner. Analysis of cell cycle distribution after treatment of MCF-7 cells with TCDD showed that LRE inhibited the proliferation of MCF-7 cells via G2/M phase arrest. Reverse transcription-polymerase chain reaction and Western blot analysis also revealed that LRE dose-dependently increased the expression of the tumor suppressor genes p53 and p27 and down-regulated the expression of cell cycle-related genes. These data suggest that LRE can mitigate the tumorigenic effects of TCDD in breast cancer cells by suppression of AhR expression and cell cycle arrest. Thus, LRE can be used as a potential toxicity-alleviating agent against EDC-mediated diseases.

Impact of the Customer Orientation and Job Satisfaction as a Result of the Consultant's Emotional Exhaustion at the Call Center (콜센터 상담원의 감정소진이 고객지향성 및 직무만족에 미치는 영향)

  • Cho, Sang-Eun;Yang, Hae-Sool
    • The Journal of the Korea Contents Association
    • /
    • v.10 no.6
    • /
    • pp.386-403
    • /
    • 2010
  • This research studied the impact of the customer orientation and job satisfaction by lowering the desire of the kind for customers and the desire for fulfillment as a result of emotional exhaustion of the consultant who performs emotion labor at the call center. This research sets study model and hypothesis to verify that call center consultant's emotional exhaustion how to effect customer orientation and job satisfaction. We took questionnaires from 157 call center(financial institutes) consultant's in Seoul for the verification of the hypothesis. I show that the consultant's emotional exhaustion had negatively affected the customer orientation and job satisfaction. In this paper proposed the importance that the experience of the consultant's emotional exhaustion who is the main agent of the performance should be minimized by removing ad improving the factors to lower emotion exhaustion through lowering time pressure in the work performance reduce the consultant's emotional exhaustion, granting work autonomy and authority, and active support of relevant departments and the ongoing communication between the managers and consultant This study makes a significant meaning in that it proposed the consultant's emotional exhaustion was negative factor on the customer orientation and job satisfaction factor in operating call center worker.

A Study of Innovation Policy regarding Technical Regulation and Conformity Assessment Procedure on ICT Equipments - Focused on Privatization Plan (CT 분야의 기술기준 및 적합성평가시스템의 혁신정책에 관한 연구: 민간화 방안을 중심으로)

  • Lee, Yong-Kyu
    • Journal of Korea Technology Innovation Society
    • /
    • v.19 no.3
    • /
    • pp.439-464
    • /
    • 2016
  • The technical regulation and conformity assessment procedure of our country on ICT equipments is currently required to have more innovation due to the request of main trade countries, the second phase conclusion of MRA, necessity of expansion of conformity assessment service market and demand of manufacturers. The world's leading advanced countries have already proceeded with innovation based on privatization plan. According to the comparative analysis of the level, it turned out that Japan obtained the highest level of privatization while South Korea ranked the lowest level. According to the research result of examination and certification ability of private institutions of our country, it turned out that our country is expected to have possibility of achieving higher level of privatization than that of the present. Moreover, according to the questionnaire survey conducted to the persons concerned regarding privatization direction, they gave positive response to all the indicated survey contents of privatization direction in terms of "delegation of certification services to private sectors (contracting-out)", "transformation of EMC into private voluntary standard" and "changeover of conformity assessment agent". However, from the view of acceptance and conflict model, it is estimated that starting from "delegation of certification services to private sectors (contracting-out)" seems to be the most advisable plan. Also, prior to privatization, it is required to improve relevant systems such as certification examiner system.

Anti-carcinogenic effects of non-polar components containing licochalcone A in roasted licorice root

  • Park, So Young;Kim, Eun Ji;Choi, Hyun Ju;Seon, Mi Ra;Lim, Soon Sung;Kang, Young-Hee;Choi, Myung-Sook;Lee, Ki Won;Yoon Park, Jung Han
    • Nutrition Research and Practice
    • /
    • v.8 no.3
    • /
    • pp.257-266
    • /
    • 2014
  • BACKGROUND/OBJECTIVE: Licorice has been shown to possess cancer chemopreventive effects. However, glycyrrhizin, a major component in licorice, was found to interfere with steroid metabolism and cause edema and hypertension. The roasting process of licorice modifies the chemical composition and converts glycyrrhizin to glycyrrhetinic acid. The purpose of this study was to examine the anti-carcinogenic effects of the ethanol extract of roasted licorice (EERL) and to identify the active compound in EERL. MATERIALS/METHODS: Ethanol and aqueous extracts of roasted and un-roasted licorice were prepared. The active fraction was separated from the methylene chloride (MC)-soluble fraction of EERL and the structure of the purified compound was determined by nuclear magnetic resonance spectroscopy. The anti-carcinogenic effects of licorice extracts and licochalcone A was evaluated using a MTT assay, Western blot, flow cytometry, and two-stage skin carcinogenesis model. RESULTS: EERL was determined to be more potent and efficacious than the ethanol extract of un-roasted licorice in inhibiting the growth of DU145 and MLL prostate cancer cells, as well as HT-29 colon cancer cells. The aqueous extracts of un-roasted and roasted licorice showed minimal effects on cell growth. EERL potently inhibited growth of MCF-7 and MDA-MB-231 breast, B16-F10 melanoma, and A375 and A2058 skin cancer cells, whereas EERL slightly stimulated the growth of normal IEC-6 intestinal epithelial cells and CCD118SK fibroblasts. The MC-soluble fraction was more efficacious than EERL in inhibiting DU145 cell growth. Licochalcone A was isolated from the MC fraction and identified as the active compound of EERL. Both EERL and licochalcone A induced apoptosis of DU145 cells. EERL potently inhibited chemically-induced skin papilloma formation in mice. CONCLUSIONS: Non-polar compounds in EERL exert potent anti-carcinogenic effects, and that roasted rather than un-roasted licorice should be favored as a cancer preventive agent, whether being used as an additive to food or medicine preparations.

Antioxidant and hepatoprotective effects of Korean ginseng extract GS-KG9 in a D-galactosamine-induced liver damage animal model

  • Jo, Yun Ho;Lee, Hwan;Oh, Myeong Hwan;Lee, Gyeong Hee;Lee, You Jin;Lee, Ji Sun;Kim, Min Jung;Kim, Won Yong;Kim, Jin Seong;Yoo, Dae Seok;Cho, Sang Won;Cha, Seon Woo;Pyo, Mi Kyung
    • Nutrition Research and Practice
    • /
    • v.14 no.4
    • /
    • pp.334-351
    • /
    • 2020
  • BACKGROUND/OBJECTIVES: This study was designed to investigate the improvement effect of white ginseng extract (GS-KG9) on D-galactosamine (Ga1N)-induced oxidative stress and liver injury. SUBJECTS/METHODS: Sixty Sprague-Dawley rats were divided into 6 groups. Rats were orally administrated with GS-KG9 (300, 500, or 700 mg/kg) or silymarin (25 mg/kg) for 2 weeks. The rats of the GS-KG9- and silymarin-treated groups and a control group were then intraperitoneally injected Ga1N at a concentration of 650 mg/kg for 4 days. To investigate the protective effect of GS-KG9 against GalN-induced liver injury, blood liver function indicators, anti-oxidative stress indicators, and histopathological features were analyzed. RESULTS: Serum biochemical analysis indicated that GS-KG9 ameliorated the elevation of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), and lactate dehydrogenase (LDH) in GalN-treated rats. The hepatoprotective effects of GS-KG9 involved enhancing components of the hepatic antioxidant defense system, including glutathione, glutathione peroxidase (GPx), superoxide dismutase (SOD), and catalase (CAT). In addition, GS-KG9 treatment inhibited reactive oxygen species (ROS) production induced by GalN treatment in hepatocytes and significantly increased the expression levels of nuclear factor erythroid-2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins, which are antioxidant proteins. In particular, by histological analyses bases on hematoxylin and eosin, Masson's trichrome, α-smooth muscle actin, and transforming growth factor-β1 staining, we determined that the administration of 500 mg/kg GS-KG9 inhibited hepatic inflammation and fibrosis due to the excessive accumulation of collagen. CONCLUSIONS: These findings demonstrate that GS-KG9 improves GalN-induced liver inflammation, necrosis, and fibrosis by attenuating oxidative stress. Therefore, GS-KG9 may be considered a useful candidate in the development of a natural preventive agent against liver injury.

A Study of Autonomous Intelligent Load Management System Based on Queueing Model (큐잉모델에 기초한 자율 지능 부하 관리 시스템 연구)

  • Lee, Seung-Chul;Hong, Chang-Ho;Kim, Kyung-Dong;Lee, In-Yong;Park, Chan-Eom
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.22 no.2
    • /
    • pp.134-141
    • /
    • 2008
  • This paper presents an innovative load management technique that can effectively lower the summer peak load by adjusting the aircondition loads through smoothe coordinations between utility companies and large customers. An intelligent hierarchical load management system composed of a Central Intelligent Load Management System(CIMS) and multiple Local Intelligent Management Systems(LIMS) is also proposed to implement the reposed technique. Upon receiving a load curtailment request from the utilities, CIMS issues tokens, which can be used by each LIMS as a right to turn on the airconditioner. CIMS creates and maintains a queue for fair allocation of the tokens among the LIMS demanding tokens. By adjusting the number tokens and queue management Policies, desired load factors can be achieved conveniently. The Markov Birth and Death Process and the Balance Equations are employed in estimating various queue performances. The proposed technique is tested using a summer load data of a large apartment complex and proved to be quite effective in load management while minimizing the customer inconveniences.

Development of Multiparticulate-system Composed of Sustained Release-microspheres of Pseudoephedrin${\cdot}$HCI and Immediate Release-pellets of Terfenadine Using Solvent Evaporation Method and Spherically Agglomerated Crystallization Process (수용성 염산슈도에페드린과 난용성 테르페나딘의 구형정석조립법과 액중미립구법을 이용한 서방성펠렛 복합제제의 개발)

  • Rhee, Gye-Ju;Do, Ki-Chan;Kim, Eun-Hee;Park, Jong-Bum;Whang, Sung-Joo
    • YAKHAK HOEJI
    • /
    • v.41 no.3
    • /
    • pp.305-311
    • /
    • 1997
  • Sustained release-microspheres and immediate release-pellets were prepared to develop a controlled release multiparticulate system containing both water soluble and insoluble dr ug. Pseudoephedrin.HCl (EPD) and terfenadine (TRF) were used as model drugs, respectively. Sustained release-EPD microspheres were prepared by solvent evaporation method using Eudragit RL or RS as a matrix combined with pH-insensitive film coating. Smaller EPD microspheres were obtained when smaller amount of Eudragit as a matrix material or larger amount of magnesium stearate as a dispersing agent was used. However the obtained microspheres did not show syfficient sustained release characteristics. About 97% of EPD was released after 1 hr irrespective of matrix material used. Subsequent coating of the microspheres with pH-insensitive polymer such as Eudragit RS or ethylcelulose (EC) resulted good sustained in 37.5, 73.3 and 92.0% release of encapsulated EPD in distilled water after 1, 3 abd 7 hr, respectively. It corresponds to mean dissolution time (MDT) of 2.3 hr, which is much larger than that of un-coated EPD microspheres (0.0048 hr). Immediate release TRF pellets were prepared by spherically agglomerated crystallization using Eudragit E as an inert matrix and methylene chloride as a liquid binder. Using Eudragit E alone as a matrix resulted in satisfactory physical properties of the pellets such as sphericity, surface texture and flowability, but led to slower release of TRF from pellets than un-modified TRF powder (MDT of 1.70 vs 1.43 hr in pH 1.2 dissolution medium). Introducing propylene glycol or sodium lauryl sulfate as an emulsifier brought about faster release of TRF from pellets (MDT of 1.14 and 0.95 hr, respectively). In conclusion, microencapsulation by solvent evaporation combined with film coating and spherically agglomerated crystallization were successfully utilized to prepare controlled release multiparticulate system composed of sustained release EPD-microspheres and immediate release TRF pellets.

  • PDF

A Study on the Institutional Improvement Arrangement of the Private Security in Korea (한국 민간경비 교육${\cdot}$제도의 문제점과 발전방안)

  • Gong, Bae-Wan
    • Korean Security Journal
    • /
    • no.12
    • /
    • pp.51-72
    • /
    • 2006
  • Recently the demand for civil bodyguards and security guards shows rapid growth. However the supply and training system have some limitations. Educational and training systems for civil body and security guards are on the basic level and private organizations trained in the professional work force. University level training started recently. To protect individual life and property, body and security guards have to be trained professionally. For it the role of professional training organizations is emphasized. The purpose of this article is to analyse current situation of civil body and security guard training industry and to seek and educational model. For it, the following questions will be examined. ${\cdot}$ Do the professional training organizations meet social demand for the body and security guards? ${\cdot}$ What kind of training has to be provided for the body and security guards? ${\cdot}$ What are the qualifications of the trainers? ${\cdot}$ What are the differences in training courses between private organizations and universities? ${\cdot}$ Is there any differences in the job placement among the trainees of private organizations and universities? In summary to meet the social demand common curriculum for the body and security guard will be drawn from the analyses of diverse training organizations with different training courses in contents, training periods, educational value, and social aim.

  • PDF

A Study on the Change of Urban Land Use According to the Change of Transportation Accessibility (교통 접근성 변동에 따른 도시 토지이용 변화에 관한 연구)

  • Won, Seok Hwan;Hwang, Chul-sue
    • Journal of Cadastre & Land InformatiX
    • /
    • v.47 no.1
    • /
    • pp.127-142
    • /
    • 2017
  • The purpose of this study is to examine the status of urbanization of Namyangju-Si from 2001 till 2008, analyze the correlation of the change of surrounding land use according to the change of accessibility and analyze the correlation of the change of land use. Based on the result from correlation analysis, I simulated from the view point of interactions between agents of land use and transportation accessibility by using MAS. I tried to forecast, based on space, the change of surrounding land use caused by the change of accessibility. I conducted landscape analysis by using a land registration map. Also, I conducted GIS analysis statistical analysis simulation analysis of traffic data, land use data in order to analyze the correlation of the change of surrounding land use according to the change of accessibility. I could find out a certain pattern that new roads and railroads causes the within 500m adjacent land to change into urban land use, which led me to construct a system through which land use changing phenomenon can be expected according to the change of accessibility. It is expected that it can make the best use of selecting the location where new transportation facilities are constructed.