• Title/Summary/Keyword: agent model

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Inhibitory activity of Euonymus alatus against alpha-glucosidase in vitro and in vivo

  • Lee, Soo-Kyung;Hwang, Ji-Yeon;Song, Ji-Hyun;Jo, Ja-Rim;Kim, Myung-Jin;Kim, Mi-Eun;Kim, Jung-In
    • Nutrition Research and Practice
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    • v.1 no.3
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    • pp.184-188
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    • 2007
  • The major goal in the treatment of diabetes mellitus is to achieve near-normal glycemic control. To optimize both fasting blood glucose and postprandial glucose levels is important in keeping blood glucose levels as close to normal as possible. ${\alpha}-Glucosidase$ is the enzyme that digests dietary carbohydrate, and inhibition of this enzyme could suppress postprandial hyperglycemia. The purpose of this study was to test the inhibitory activity of methanol extract of Euonymus alatus on ${\alpha}-glucosidase$ in vitro and in vivo to evaluate its possible use as an anti-diabetic agent. Yeast ${\alpha}-glucosidase$ inhibitory activities of methanol extract of E. alatus were measured at concentrations of 0.50, 0.25, 0.10, and 0.05 mg/ml. The ability of E. alatus to lower postprandial glucose was studied in streptozotocin-induced diabetic rats. A starch solution (1 g/kg) with and without E. alatus extract (500 mg/kg) was administered to diabetic rats by gastric intubation after an overnight fast. Plasma glucose levels were measured at 30, 60, 90, 120, 180, and 240 min. Plasma glucose levels were expressed in increments from baseline, and incremental areas under the response curve were calculated. Extract of E. alatus, which had an $IC_{50}$ value of 0.272 mg/ml, inhibited yeast ${\alpha}-glucosidase$ activity in a concentration-dependent manner. A single oral dose of E. alatus extract significantly inhibited increases in blood glucose levels at 60 and 90 min (p<0.05) and significantly decreased incremental response areas under the glycemic response curve (p<0.05). These results suggest that E. alatus has an antihyperglycemic effect by inhibiting ${\alpha}-glucosidase$ activity in this animal model of diabetes mellitus.

Combined MRI and Relaxogram: A New Method of Fat Study (MRI와 Relaxogram을 이용한 지질 연구의 새로운 기법에 관한 연구)

  • Yongmin Chang;Yoo, Done-Sik;Kim, Tae-Hun;Kim, Yong-Joo;Kang, Duk-Sik;Robert B. Clarkson
    • Progress in Medical Physics
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    • v.10 no.1
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    • pp.23-32
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    • 1999
  • Combined MRI and Relaxogram approach was introduced as a very useful tool for fat study. The phantoms simulating homogeneous mixture of fat and non-fat environments were measured with spin echo pulse sequence on a 0.15 T whole body imager. From 45 scans, the Tl values were obtained by fitting the data to continuous distribution (CONTIN) of relaxation time. This relaxogram gives broad distributions of relaxation time, which are characterized by a number of peaks with characteristic T1 values. Two distinct peaks in relaxogram were observed and identified as signals from com oil and gelatin gel. This model system can be served as simulating the distribution of fat in muscle. Also the relative ratio of two components, which is proportional to the area under the peak, is estimated and compared to nominal values. Based on the good agreement between two predictions, the values from our proposed method agreed with nominal values within $\pm$7 % error. The effects of different concentration of contrast agent and different region of interest are presented. To optimize total scan times, the minimum required data points and so further reduction in total scan times are discussed.

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Dynamic Polling Algorithm Based on Line Utilization Prediction (선로 이용률 예측 기반의 동적 폴링 기법)

  • Jo, Gang-Hong;An, Seong-Jin;Jeong, Jin-Uk
    • The KIPS Transactions:PartC
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    • v.9C no.4
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    • pp.489-496
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    • 2002
  • This study proposes a new polling algorithm allowing dynamic change in polling period based on line utilization prediction. Polling is the most important function in network monitoring, but excessive polling data causes rather serious congestion conditions of network when network is In congestion. Therefore, existing multiple polling algorithms decided network congestion or load of agent with previously performed polling Round Trip Time or line utilization, chanced polling period, and controlled polling traffic. But, this algorithm is to change the polling period based on the previous polling and does not reflect network conditions in the current time to be polled. A algorithm proposed in this study is to predict whether polling traffic exceeds threshold of line utilization on polling path based on the past data and to change the polling period with the prediction. In this study, utilization of each line configuring network was predicted with AR model and violation of threshold was presented in probability. In addition, suitability was evaluated by applying the proposed dynamic polling algorithm based on line utilization prediction to the actual network, reasonable level of threshold for line utilization and the violation probability of threshold were decided by experiment. Performance of this algorithm was maximized with these processes.

Cytotoxicity of Hyaluronic Acid Membrane Cross-linked with Lactide (락타이드로 가교시킨 히아루론산 막의 세포독성)

  • Kim, Won-Jung;Kwon, Ji-Young;Cheong, Seong-Ihl;Kim, In-Seop
    • KSBB Journal
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    • v.21 no.4
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    • pp.255-259
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    • 2006
  • The biodegradable hyaluronic acid(HA) membranes cross-linked with lactide using the crosslinking agent, 1-ethyl-3(3-dimethyl aminopropyl) carbodiimide(EDC) were prepared as a potential biocompatible material for tissue engineering. HA membranes having different mechanical properties were synthesised by varying degree of the mole ratio of lactide to HA, EDC concentration, and crosslinking temperature. HA membranes were degradable in water solution and the degradation became slower with the increasing mole ratio of lactide to HA. HA membranes were sterilized using ethylene oxide gas and extracted with cell culture medium for 24 h at $37^{\circ}C$ and 200 rpm. Cytotoxicity of the extract was tested using NIH/3T3 mouse embryo fibroblast as a model cell. Growth inhibition was not observed in the extracts of HA membranes with the mole ratios of lactide to HA, 5 or 10, and 10% EDC concentration, however 11% of growth inhibition was observed in the extract with the mole ratio of 13. Growth inhibition was not observed in the extracts of HA membranes prepared with 5% EDC or 10% EDC and the mole ratio of lactide to HA, 10, however 12% of growth inhibition was observed in the extract with 20% EDC. Cytotoxicity was not observed in the extracts of HA membranes prepared at varying crosslinking temperatures, $15^{\circ}C,\;25^{\circ}C,\;and\;28^{\circ}C$ with the mole ratio of lactide to HA, 10 and 10% EDC.

Development of CCTV Cooperation Tracking System for Real-Time Crime Monitoring (실시간 범죄 모니터링을 위한 CCTV 협업 추적시스템 개발 연구)

  • Choi, Woo-Chul;Na, Joon-Yeop
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.546-554
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    • 2019
  • Typically, closed-circuit television (CCTV) monitoring is mainly used for post-processes (i.e. to provide evidence after an incident has occurred), but by using a streaming video feed, machine-based learning, and advanced image recognition techniques, current technology can be extended to respond to crimes or reports of missing persons in real time. The multi-CCTV cooperation technique developed in this study is a program model that delivers similarity information about a suspect (or moving object) extracted via CCTV at one location and sent to a monitoring agent to track the selected suspect or object when he, she, or it moves out of range to another CCTV camera. To improve the operating efficiency of local government CCTV control centers, we describe here the partial automation of a CCTV control system that currently relies upon monitoring by human agents. We envisage an integrated crime prevention service, which incorporates the cooperative CCTV network suggested in this study and that can easily be experienced by citizens in ways such as determining a precise individual location in real time and providing a crime prevention service linked to smartphones and/or crime prevention/safety information.

Diagnosis of fibroadenoma using radiolabeled bladder cancer specific peptide

  • Ha, Yeong Su;Kwak, Wonjung;Lee, Hwa Young;Lee, Byung-Heon;Hong, Il-Hwa;Jeong, Kyu-Shik;An, Gwang Il;Yoo, Jeongsoo
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.1 no.1
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    • pp.38-45
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    • 2015
  • Most tumors are believed to overexpress several receptors, and small peptides targeting these receptors were developed for diagnosis and tumor therapy during past decade. Here we report that fibroadenoma can be visualized by bladder cancer specific peptide. A 9-mer bladder cancer specific peptide, which was discovered from the phage display method, was synthesized by peptide synthesizer, and additional tyrosine was conjugated at the N-terminal for radioiodination (Y-BP). Y-BP was radiolabeled with $^{131/124}I$ using Iodogen tube. The rat treated with N-butyl-N-(4-hydroxybutyl)nitrosamine for 8 weeks was allowed to grow until large size tumor was developed under axilla. The tumor model was microPET imaged sequentially using [$^{18}F$]FDG and radioiodinated $^{124}I-Y-BP$. The tumor was excised and examined by immunostaining studies. Radioiodinated $^{124}I-Y-BP$ was purified using fast protein liquid chromatography (FPLC) in > 90% radiochemical purity. The whole tumor was well visualized by [$^{18}F$]FDG with several intense focal uptake within tumor. The tumor was also clearly seen with $^{124}I-Y-BP$ at 4 h post-injection, and to our surprise the tumor uptake of $^{124}I-Y-BP$ lasted up to three days. The tumor was diagnosed histologically as a fibroadenoma derived from mammary gland. In conclusion, the bladder cancer specific peptide showed the good potential as a new radiotracer for the detection of breast fibroadenoma.

Evaluation of Interlayer Shear Properties and Bonding Strengths of a Stress-Absorbing Membrane Interlayer and Development of a Predictive Model for Fracture Energy (덧씌우기 응력흡수층에 대한 전단, 부착강도 평가 및 파괴에너지 예측모델 개발)

  • Kim, Dowan;Mun, Sungho;Kwon, Ohsun;Moon, Kihoon
    • International Journal of Highway Engineering
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    • v.20 no.1
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    • pp.87-95
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    • 2018
  • PURPOSES : A geo-grid pavement, e.g., a stress-absorbing membrane interlayer (SAMI), can be applied to an asphalt-overlay method on the existing surface-pavement layer for pavement maintenance related to reflection cracking. Reflection cracking can occur when a crack in the existing surface layer influences the overlay pavement. It can reduce the pavement life cycle and adversely affect traffic safety. Moreover, a failed overlay can reduce the economic value. In this regard, the objective of this study is to evaluate the bonding properties between the rigid pavement and a SAMI by using the direct shear test and the pull-off test. The predicted fractural energy functions with the shear stress were determined from a numerical analysis of the moving average method and the polynomial regression method. METHODS : In this research, the shear and pull-off tests were performed to evaluate the properties of mixtures constructed using no interlayer, a tack-coat, and SAMI with fabric and without fabric. The lower mixture parts (describing the existing pavement) were mixed using the 25-40-8 joint cement-concrete standard. The overlay layer was constructed especially using polymer-modified stone mastic asphalt (SMA) pavement. It was composed of an SMA aggregate gradation and applied as the modified agent. The sixth polynomial regression equation and the general moving average method were utilized to estimate the interlayer shear strength. These numerical analysis methods were also used to determine the predictive models for estimating the fracture energy. RESULTS : From the direct shear test and the pull-off test results, the mixture bonded using the tack-coat (applied as the interlayer between the overlay layer and the jointed cement concrete) had the strongest shear resistance and bonding strength. In contrast, the SAMI pavement without fiber has a strong need for fractural energy at failure. CONCLUSIONS : The effects of site-reflection cracking can be determined using the same tests on cored specimens. Further, an empirical-mechanical finite-element method (FEM) must be done to understand the appropriate SAMI application. In this regard, the FEM application analy pavement-design analysis using thesis and bonding property tests using cored specimens from public roads will be conducted in further research.

Impact on Inflammation and Recovery of Skin Barrier by Nordihydroguaiaretic Acid as a Protease-Activated Receptor 2 Antagonist

  • Kim, Hyo-Young;Goo, Jung-Hyun;Joo, Yeon-Ah;Lee, Ha-Yoen;Lee, Se-Mi;Oh, Chang-Taek;Ahn, Soo-Mi;Kim, Nam-Hoon;Hwang, Jae-Sung
    • Biomolecules & Therapeutics
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    • v.20 no.5
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    • pp.463-469
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    • 2012
  • Atopic dermatitis is a chronic, inflammatory disease of the skin with increased transepidermal water loss. Both an abnormal inflammatory response and a defective skin barrier are known to be involved in the pathogenesis of atopic dermatitis. Protease activated receptor 2 (PAR2) belongs to a family of G-protein coupled receptors and is activated by both trypsin and a specific agonist peptide, SLIGKV-$NH_2$. PAR2 is expressed in suprabasal layers of the epidermis and regulates inflammatory responses and barrier homeostasis. In this study, we show that nordihydroguaiaretic acid (NDGA) inhibits the PAR2-mediated signal pathway and plays a role in skin barrier recovery in atopic dermatitis. Specifically, NDGA reduces the mobilization of intracellular $Ca^{2+}$ in HaCaT keratinocytes by down-regulating inflammatory mediators, such as interleukin-8, thymus and activation-regulated chemokine and intercellular cell adhesion molecule-1 in HaCaT keratinocytes. Also, NDGA decreases the protein expression of involucrin, a differentiation maker of keratinocyte, in both HaCaT keratinocytes and normal human epidermal keratinocytes. We examined NDGA-recovered skin barrier in atopic dermatitis by using an oxazolone-induced atopic dermatitis model in hairless mice. Topical application of NDGA produced an increase in transepidermal water loss recovery and a decrease in serum IgE level, without weight loss. Accordingly, we suggest that NDGA acts as a PAR2 antagonist and may be a possible therapeutic agent for atopic dermatitis.

Effect of Selenium on the Thyroid gland Antioxidative Metabolisms in Rat Model by Ionizing Radiation (셀레늄이 전리방사선에 의한 힌쥐 모델에서의 갑상선 항산화계에 미치는 영향)

  • Choi, Hyung-Seok;Choi, Jun-Hyeok;Jung, Do-Young;Kim, Jang-Oh;Shin, Ji-Hye;Min, Byung-In
    • Journal of radiological science and technology
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    • v.40 no.1
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    • pp.135-142
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    • 2017
  • Selenium (Se), which is natural materials existing was known as an important component of selenoprotein, one of the important proteins responsible for the redox pump of a living body. Selenium was orally administered to Rat and irradiated with 10 Gy of radiation. Then, the thyroid gland was used as a target organ for 1 day, 7 days and 21 days to investigate the radiation protection effect of selenium (Se) through changes of blood components, thyroid hormones (T3, T4), antioxidant enzyme (GPx) activity and thyroid tissue changes. As a result, there was a significant protective effect of hematopoietic immune system(hemoglobin concentration, neutrophil, platelet)(p<0.05). The activity of Glutathione Peroxidase (GPx), the antioxidant enzyme, and the activity of the target organ, thyroid hormone (T3, T4), also showed significant activity changes (p<0.05). In the observation of tissue changes, it was confirmed that there was a protective effect of thyroid cell damage which caused the cell necrosis by radiation treatment. Therefore, it is considered that selenium(Se) can be utilized as a radiation defense agent by inducing immunogenic activity effect of a living body.

Design and Implementation of Process Management Model applying Agent Technology (헬스케어 홈 서비스를 위한 데이터베이스 및 응용 서비스 구현)

  • Lee, Chung-Sub;Jeong, Chang-Won;Joo, Su-Chong
    • Journal of Internet Computing and Services
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    • v.8 no.1
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    • pp.57-70
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    • 2007
  • This paper is to construct a healthcare database using information obtained from healthcare home environments, and use this one for healthcare home services, Especially, our researching focus in this paper is how to design healthcare database scheme and how to use this constructed database on the Framework for Supporting Healthcare Integrated Service(FSHIS) we developed previously. Healthcare information is designed to database schemes in accordance to the specific save types of the data collected from various typed-sensors. The healthcare database constructed by using this information for the purpose of healthcare home services is divided into the base information with real schemes and the context based information with view schemes. Firstly, the base information includes low data obtained from physical sensors relevant to locations, healths, environments, and the personnel healthy profiles. The other is the context based information that is produced and fused by using the based information. This context based information might be got via various view schemes according to healthcare application services. Finally, for verifying the practical use of healthcare database constructed in this paper, Via interconnecting this database to our FSHIS, we show an example of healthcare home monitoring service using information (basic and context based information), emergency call, home appliance control, and so on needed from living activity area for elderly living alone.

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