• Title/Summary/Keyword: Knowledge flow

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Cl--Channel Is Essential for LDL-induced Cell Proliferation via the Activation of Erk1/2 and PI3K/Akt and the Upregulation of Egr-1 in Human Aortic Smooth Muscle Cells

  • Heo, Kyung-Sun;Ryoo, Sung-Woo;Kim, Lila;Nam, Miyoung;Baek, Seung-Tae;Lee, Hyemi;Lee, Ah-Reum;Park, Song-Kyu;Park, Youngwoo;Myung, Chang-Seon;Kim, Dong-Uk;Hoe, Kwang-Lae
    • Molecules and Cells
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    • v.26 no.5
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    • pp.468-473
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    • 2008
  • Low-density lipoprotein (LDL) induces cell proliferation in human aortic smooth muscle cells (hAoSMCs), which may be involved in atherogenesis and intimal hyperplasia. Recent studies have demonstrated that $Cl^-$ channels are related to vessel cell proliferation induced by a variety of stimuli. In this study, we investigated a potential role of $Cl^-$ channels in the signaling pathway of LDL effects on hAoSMC proliferation with a focus on the activation of Erk1/2-PI3K/Akt and the subsequent upregulation of Egr-1. $Cl^-$ channel blockers, DIDS, but neither NPPB nor Furosemide, completely abolished the LDL-induced DNA synthesis and cell proliferation. Moreover, DIDS, but not NPPB, significantly decreased LDL-stimulated $Cl^-$ concentration, as judged by flow cytometry analysis using MQAE as a $Cl^-$-detection dye. DIDS pretreatment completely abolished the activation of Erk1/2 and PI3K/Akt in a dose-dependent manner that is the hallmark of LDL activation, as judged by Western blot and proliferation assays. Moreover, pretreatment with DIDS ($Cl^-$ channel blockers) but not LY294002 (PI3K inhibitors) completely abolished the LDL-induced upregulation of Egr-1 to the same extent as PD98059 (MEK inhibitors to inhibit Erk), as judged by Western blot and luciferase reporter assays. This is the first report, to our knowledge, that DIDS-sensitive $Cl^-$-channels play a key role in the LDL-induced cell proliferation of hAoSMCs via the activation of Erk1/2 and PI3K/Akt and the upregulation of Egr-1.

Finding the time sensitive frequent itemsets based on data mining technique in data streams (데이터 스트림에서 데이터 마이닝 기법 기반의 시간을 고려한 상대적인 빈발항목 탐색)

  • Park, Tae-Su;Chun, Seok-Ju;Lee, Ju-Hong;Kang, Yun-Hee;Choi, Bum-Ghi
    • Journal of The Korean Association of Information Education
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    • v.9 no.3
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    • pp.453-462
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    • 2005
  • Recently, due to technical improvements of storage devices and networks, the amount of data increase rapidly. In addition, it is required to find the knowledge embedded in a data stream as fast as possible. Huge data in a data stream are created continuously and changed fast. Various algorithms for finding frequent itemsets in a data stream are actively proposed. Current researches do not offer appropriate method to find frequent itemsets in which flow of time is reflected but provide only frequent items using total aggregation values. In this paper we proposes a novel algorithm for finding the relative frequent itemsets according to the time in a data stream. We also propose the method to save frequent items and sub-frequent items in order to take limited memory into account and the method to update time variant frequent items. The performance of the proposed method is analyzed through a series of experiments. The proposed method can search both frequent itemsets and relative frequent itemsets only using the action patterns of the students at each time slot. Thus, our method can enhance the effectiveness of learning and make the best plan for individual learning.

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EXPRESSION OF THE GENES OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND VON WILLEBRAND FACTOR IN SALIVARY GLAND TUMORS (타액선 종양에서 혈관내피성장인자와 von Willebrand 인자 유전자 발현에 관한 연구)

  • Chung, Ji-Hun;Kim, Ji-Hyuk;Park, Young-Wook
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.30 no.1
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    • pp.41-51
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    • 2008
  • Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumor which compromises about 6$\sim$8% of all tumors followed by the adenoid cystic carcinoma (ACC) and adenocarcinoma. Most deaths from salivary carcinomas are caused by recurrent or metastatic lesions that are resistant to conventional therapy. Therefore, knowledge of cellular properties and tumor-host interactions that influence the vascular metastasis is important for the design of more effective therapy of salivary carcinomas. Neoangiogenesis is essential for tumor growth, which is postulated to be fundamentally dependent on the induction of stromal neovascularization. However, how neovascularization takes place in live tissue has not been fully established, especially in recruitment and differentiation of endothelial cells in the salivary gland tumors. Vascular endothelial growth factor (VEGF) is a heparin-binding, dimeric polypeptide growth factor known to exert its mitogenic activity specifically on endothelial cells. VEGF has been shown th be directly involved in angiogenesis, which in essential for the pathogenesis of many solid tumors. von Willebrand factor (vWF) is a large multimeric protein synthesized by megakaryocytes and endothelial cells that enable platelets to adhere to exposed subendothelium and, as well, to respond to changes in the blood flow. Recent studies suggest that increased levels of vWF correlate with progression of disease, metastasis, or survival time and thus may have a prognostic significance. vWF is explained as an acute phase proteins which is increased in cancer or as a result of increased endothelial cell synthesis associated with tumor-induced angiogenesis. Due to adhesive properties of vWF, its increased concentrations may also contribute metastasis of tumor. In this study, we determined the mRNA expression of VEGF and vWF in salivary ACC, MEC and pleomorphic adenoma by in situ hybridization. As a result, stronger expression of VEGF and vWF was seen in salivary ACC and MEC which has more invasive nature than the salivary benign tumor.

Measurement of $\textrm{CO}_2$ Concentration and Leaf Area Index for Crop Photosynthesis Model in Sweet Pepper (단고추의 작물 광합성 모델을 위한 $\textrm{CO}_2$ 농도와 엽면적지 수 측정)

  • Lee, Beom-Seon;Chung, Soon-Ju;Jang, Hong-Gi
    • Journal of Bio-Environment Control
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    • v.8 no.3
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    • pp.192-201
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    • 1999
  • This study was aimed to introduce the measurement of $CO_2$ concentration and leaf area index in the phytotron for predicting the effect of CO.E, light and leaf area index on the instantaneous photosynthetic rate of sweet pepper with the existing ASKAM model. Measurements were made in 2 semi-closed phytotron compartments in which three different $CO_2$ concentrations were applied at random. Plants were grown on containers with circulating nutrient solution at 21$^{\circ}C$ and 80-95% relative humidity. The model estimates crop net $CO_2$ uptake for short time intervals during the day based on short-term data of daily radiation, temperature and $CO_2$ concentration. During the photosynthesis measurements, $CO_2$ concentrations in both compartments and in the basement were measured every minute. This was also done for the flow of pure $CO_2$ into the compartment, global radiation, photosynthetic active radiation inside the compartment, temperature and relative humidity. Crop growth models summarize our knowledge on crop behavior and have as such a wide range of applications in analysis, crop management and thus as a farm management tool.

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Induction of Apoptosis in Human Osteosarcoma Cell Lines(Saos-2) by Single Fraction High Dose Irradiation (고용량 방사선 조사 후 골육종 세포주(Saos-2)의 아포프토시스 발생)

  • Kim, Jae-Do;Chung, So-Hak;Hong, Young-Gi;Choi, Jang-Seok
    • The Journal of the Korean bone and joint tumor society
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    • v.5 no.1
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    • pp.1-8
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    • 1999
  • A single fraction of 50 Gy extracorporeal irradiation, as a modality of limb-sparing operation, has been used to achieve tumor necrosis in osteosarcoma. Although this modality of radiation therapy preserving the mobility of a joint is commonly practiced, the precise knowledge on the radiobiological response of osteosarcoma cell has remained to be elucidated. We therefore observed whether a single high dose irradiation caused apoptosis in osteosarcoma cells and whether the commitment to apoptosis was associated with cell kinetics. We also investigated radiation dose response along the time course for development of apoptosis following single high dose irradiation. The morphologic change in apoptosis was observed by fluorescence with Hoechst 33258 and the degree and the fraction of cells by flow cytometry. Irradiation of osteosarcoma cells with 10, 30 and 50 Gy resulted in chromatin condensation and apoptotic body formation. The degree of apoptosis in osteosarcoma cells was $29.5{\pm}3.56%$, $39.9{\pm}4.83%$ at 24 and 48 hours after 10 Gy irradiation ; $41.1{\pm}3.93%$, $66.9{\pm}5.21%$ at 24 and 48 hours after 30 Gy irradiation ; and $48.0{\pm}3.69%$, $75.6{\pm}4.65%$ at 24 and 48 hours after 50 Gy irradiation. The fraction of cells in cell-cycle kinetic was $39.2{\pm}4.3%$ in G2/M, $22.1{\pm}4.65%$ in G1 at 24 hours after 10 Gy irradiation ; $51.0{\pm}4.3%$ in G2/M, $20.4{\pm}4.7%$ in G1 at 48 hours after 10 Gy irradiation ; $40.3{\pm}3.9%$ in G2/M, $26.1{\pm}4.7%$ in G1 at 24 hours after 30 Gy irradiation ; $59.2{\pm}3.9%$ in G2/M, $5.9{\pm}5.1%$ in G1 at 48 hours after 30 Gy irradiation ; and $44.3{\pm}4.2%$ in G2/M, $21.1{\pm}3.5%$ in G1 at 24 hours after 50 Gy irradiation. The fraction of cells at 48 hours after 50 Gy irradiation could not be observed because of irradiation induced cell death of most of cells. All values for irradiated cells showed accumulation in G2/M phase and reduction in G1 phase, irrespective of irradiation dose. The results suggest that a single fraction of high dose irradiation with 50 Gy results in accumulation of cells at G2/M phase, leading to apoptosis.

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A Review on Stress and Coping Level at Dysmenorrhea Perceived by Middle School Girls in Seoul (월경곤란시 여자중학생이 지각하는 스트레스 및 그 대응에 관한 소고)

  • Jung Moon-Hee
    • Journal of Korean Public Health Nursing
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    • v.5 no.2
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    • pp.45-51
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    • 1991
  • The purpose of this study is to investigate the stress and coping level as a result of dysmenorrhea which was experienced by girls. For the collection of data, the girls from the 1st to the 3rd grade in middle school in Seoul were selected through a random sampling technique. The survey was conducted from the 1st. to the 14th of June, 1991 by the use of questionnaires made after a pilot study. The final subjects for analysis were restricted to only those who had experienced me~arche, the number of which totaled 1,131. The stress, coping level, and other variables, were tested and analysed by descriptive statistics (eg, frequency, percentage, mean and standard deviation), t-test, ANOVA and Pearson's correlation coefficients. The obtained results are summarized as follows. 1. The chronological start for menarche was at a mean age of 13.1 The respondents who had experienced menarche numbered $70.9\%$ of the 1st grades and $96.2\%$ of the 2nd grades in middle school, otherwise the starting age for menarche was in the 4th grade in primary school. 2. Their menstrual cycle and period were longer than adult's one. The number of students studied who had experienced dysmenorrhea during their menstrual cycle were 860, and 650 of those revealed that their mothers or sisters had experienced similar problems. 3. The subjects who were late or head left early rather than being absent from school every menstruation cycle were more stressful. The results are thought to show that the girl's perception of dysmenorrhea seems to be more sensitive than adult's one. 4, A significant negative correlation was found between the perception of menstrual flow and strees level. It means that an increase in the stress of dysmenorrhea was associated with decreased menstrual bleeding. The degree of hypochondrical concern assessed by the girls was significantly correlated to stress and coping level. When the girls perceived high stress as a result of dysmenorrhea, they worried about their physical health more. The above results lead us to the suggestion that the starting point of early education with a school program is appropriate for the 4th grade in primary school. Especially if the girls in middle school should be required to give the information about correct knowledge and sufficient self -care management of menstruation monthly, if this could be implemented the loss in school days among the students due to dysmenorrhea would be minimized with more ease.

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Moxibustion for Benign Prostatic Hyperplasia: A Systematic Review and Meta-analysis (전립선 비대증에 대한 뜸치료의 효과 : 체계적 문헌고찰과 메타분석)

  • Bae, Go-eun;Lee, Seung-hwan;Hong, Jin-woo;Lee, In;Kim, So-yeon;Choi, Jun-young;Han, Chang-woo;Yun, Young-ju;Park, Seong-ha;Kwon, Jung-nam
    • The Journal of Internal Korean Medicine
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    • v.39 no.3
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    • pp.372-388
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    • 2018
  • Objective: This study evaluates the effectiveness and safety of moxibustion for benign prostatic hyperplasia (BPH). Methods: Using the keywords "benign prostatic hyperplasia", "benign prostatic hypertrophy", "benign prostatic enlargement", "prostatic hyperplasia", and "moxibustion", we searched papers in numerous databases, including National Discovery for Science Leaders (NDSL), Korean Traditional Knowledge Portal (KTKP), Oriental Medicine Advanced Searching Integrated System (OASIS), Research Information Sharing Service (RISS), PubMed, Embase, and CENTRAL. The search range included randomized controlled trials (RCTs). Papers not matched with inclusion criteria were excluded. The methodological quality of each RCT was assessed using the Cochrane risk-of-bias tool. Where appropriate, meta-analyses were performed. Results: Initially, 77 studies were found. Of these, 11 duplicate studies were removed and 27 were excluded following title and abstract screening. After the remaining 39 papers were scanned, 13 RCTs were selected and analyzed. Among these 13 RCTs, five compared moxibustion therapy and oral medication, seven compared moxibustion plus acupuncture therapy and oral medication, and one compared moxibustion plus acupuncture therapy and sham-moxibustion. The meta-analysis showed positive results for the use of moxibustion therapy in terms of International Prostate Symptom Score (IPSS), Quality Of Life (QOL), Maximum Flow Rate (Qmax), Prostate Volume (PV), and the efficacy rate. The meta-analysis showed positive results for the use of moxibustion plus acupuncture therapy in terms of IPSS, QOL, and the efficacy rate. Conclusions: This meta-analysis of clinical trials suggests that moxibustion is effective intreating BPH patients. The results of this study could be applied to clinical treatment of BPH. However, additional large-scale clinical researches should be conducted.

Flower Color Modification by Manipulating Flavonoid Biosynthetic Pathway (플라보노이드 대사 조절을 통한 화색 변경)

  • Lim, Sun-Hyung;Kim, Jae-Kwang;Kim, Dong-Hern;Sohn, Seong-Han;Lee, Jong-Yeol;Kim, Young-Mi;Ha, Sun-Hwa
    • Horticultural Science & Technology
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    • v.29 no.6
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    • pp.511-522
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    • 2011
  • Flower color is one of the main target traits in the flower breeding. Recently, technological advances in genetic engineering have been successfully reported the flower colors, such as blue roses and blue carnations that are impossible to develop by traditional breeding. Accumulated knowledge-based approaches for flavonoid biosynthesis enabled to introduce novel and unique colors into flowers. These flower color modifications have been made through the regulation of flavonoid metabolic pathway - control of endogenous gene expression and introduction of foreign genes to produce novel and specific flavonoids - and the introduction of transcription factors that are known to regulate sets of genes being involving in the flavonoid biosynthetic pathway. More empirical regulation of the flavonoids metabolism requires the understanding for regulatory mechanism of intrinsic flavonoids depending on the flower crops and the very sophisticated control of flavonoid metabolic flow. In this review, we summarized successful examples of flower color modification. It might be useful to deduce the strategy for the creation of exquisite colors in flower plants.

Involvement of Lysosome Membrane Permeabilization and Reactive Oxygen Species Production in the Necrosis Induced by Chlamydia muridarum Infection in L929 Cells

  • Chen, Lixiang;Wang, Cong;Li, Shun;Yu, Xin;Liu, Xue;Ren, Rongrong;Liu, Wenwen;Zhou, Xiaojing;Zhang, Xiaonan;Zhou, Xiaohui
    • Journal of Microbiology and Biotechnology
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    • v.26 no.4
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    • pp.790-798
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    • 2016
  • Chlamydiae, obligate intracellular bacteria, are associated with a variety of human diseases. The chlamydial life cycle undergoes a biphasic development: replicative reticulate bodies (RBs) phase and infectious elementary bodies (EBs) phase. At the end of the chlamydial intracellular life cycle, EBs have to be released to the surrounded cells. Therefore, the interactions between Chlamydiae and cell death pathways could greatly influence the outcomes of Chlamydia infection. However, the underlying molecular mechanisms remain elusive. Here, we investigated host cell death after Chlamydia infection in vitro, in L929 cells, and showed that Chlamydia infection induces cell necrosis, as detected by the propidium iodide (PI)-Annexin V double-staining flow-cytometric assay and Lactate dehydrogenase (LDH) release assay. The production of reactive oxygen species (ROS), an important factor in induction of necrosis, was increased after Chlamydia infection, and inhibition of ROS with specific pharmacological inhibitors, diphenylene iodonium (DPI) or butylated hydroxyanisole (BHA), led to significant suppression of necrosis. Interestingly, live-cell imaging revealed that Chlamydia infection induced lysosome membrane permeabilization (LMP). When an inhibitor upstream of LMP, CA-074-Me, was added to cells, the production of ROS was reduced with concomitant inhibition of necrosis. Taken together, our results indicate that Chlamydia infection elicits the production of ROS, which is dependent on LMP at least partially, followed by induction of host-cell necrosis. To our best knowledge, this is the first live-cell-imaging observation of LMP post Chlamydia infection and report on the link of LMP to ROS to necrosis during Chlamydia infection.

On the Sequences of Dialogue Acts and the Dialogue Flows-w.r.t. the appointment scheduling dialogues (대화행위의 연쇄관계와 대화흐름에 대하여 -[일정협의 대화] 중심으로)

  • 박혜은;이민행
    • Korean Journal of Cognitive Science
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    • v.10 no.2
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    • pp.27-34
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    • 1999
  • The main purpose of this paper is to propose a general dialogue flow in 'the a appointment scheduling dialogues' in German using the concept of dialogue acts. A basic a assumption of this research is that dialogue acts contribute to the improvement of a translation system. They might be very useful to solve the problems that syntactic and semantic module could not resolve using contextual knowledge. The classification of the dialogue acts was conducted as a work of VERBMOBIL project and was based on real dialogues transcribed by experts. The real dialogues were analyzed in terms of the dialogue acts. We empirically analyzed the sequences of the dialogue acts not only in a series of dialogue turns but also in one dialogue turn. We attempted to analyZe the sequences in one dialogue turn additionally because the dialogue data used in this research showed some difference from the ones in other existing researches. By examining the sequences in dialogue acts. we proposed the dialogue flowchart in 'the a appointment scheduling dialogues' 'Based on the statistical analysis of the sequences of the most frequent dialogue acts. the dialogue flowcharts seem to represent' the a appointment scheduling dialogues' in general. A further research is required on c classification of dialogue acts which was a base for the analysis of dialogues. In order to e extract the most generalized model. we did not subcategorize each dialogue acts and used a limited number of items of dialogue acts. However. generally defined dialogue acts need to be defined more concretely and new dialogue acts for specific situations should be a added.

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