• Title/Summary/Keyword: Background formation

Search Result 781, Processing Time 0.027 seconds

Parecoxib: an Enhancer of Radiation Therapy for Colorectal Cancer

  • Xiong, Wei;Li, Wen-Hui;Jiang, Yong-Xin;Liu, Shan;Ai, Yi-Qin;Liu, Rong;Chang, Li;Zhang, Ming;Wang, Xiao-Li;Bai, Han;Wang, Hong;Zheng, Rui;Tan, Jing
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.2
    • /
    • pp.627-633
    • /
    • 2015
  • Background: To study the effect of parecoxib, a novel cyclooxygenase-2 selective inhibitor, on the radiation response of colorectal cancer (CRC) cells and its underlying mechanisms. Materials and Methods: Both in vitro colony formation and apoptosis assays as well as in vivo mouse xenograft experiments were used to explore the radiosensitizing effects of parecoxib in human HCT116 and HT29 CRC cells. Results: Parecoxib sensitized CRC cells to radiation in vitro with a sensitivity enhancement ratio of 1.32 for HCT116 cells and 1.15 for HT29 cells at a surviving fraction of 0.37. This effect was partially attributable to enhanced apoptosis induction by parecoxib combined with radiation, as illustrated using an in vitro apoptosis assays. Parecoxib augmented the tumor response of HCT116 xenografts to radiation, achieving growth delay more than 20 days and an enhancement factor of 1.53. In accordance with the in vitro results, parecoxib combined with radiation resulted in less proliferation and more apoptosis in tumors than radiation alone. Radiation monotherapy decreased microvessel density (MVD) and microvessel intensity (MVI), but increased the hypoxia level in xenografts. Parecoxib did not affect MVD, but it increased MVI and attenuated hypoxia. Conclusions: Parecoxib can effectively enhance radiation sensitivity in CRC cells through direct effects on tumor cells and indirect effects on tumor vasculature.

A Study on Fashion Design Applied from Color-Field Abstract of Matk Rothko: Focusing on Needle-Punching Felt Technique

  • Park, Kyung-Mi;Lee, Mi-Ryang
    • The International Journal of Costume Culture
    • /
    • v.13 no.2
    • /
    • pp.141-153
    • /
    • 2010
  • Fashion needs to be understood as practicality and creative behavior and various movements of paintings act as inspirations of original design for fashion designers. This study seeks to find sources of fashion designs in the works of Mark Rothko who is in the center of color-field abstract. Color-field of Rothko provides infinite inspirations as colors are identically treated as shapes and lighting and textures are all included on top of it. In this study, the purpose is to create color focused artistic fashion design by exploring the possibility of expression with the colors of Rothko as the main motive. The study method is as follows. First, the concept and significance of color-field abstract are researched through documented data. Works of Rothko is divided into three periods according to their characteristics. The background of the formation of color-field abstract of Rothko is understood by analyzing the trends of the works in each period. Second, twenty representative works from 1949 to 1969 are selected and analyzed in formative components of color, shape and textures in order to more accurately understand shape of colors, brilliance, simplicity that appear in the mature color-field abstract of Rothko. Third, preexisting methods of color-field of paintings developed into motives of clothing are studied focusing on the collections from 1997 to 2006. Examples of applications of color-field images in modern fashion designs are analyzed. Fourth, motives are selected based on general characteristics of color-field abstract of Rothko and the results of the formative analysis. Clothing is produced that expresses the colors of the paintings of Rothko more effectively. As the results of the study, restrained shapes and textures and various forms of color combinations shown in color-field abstract of Rothko provided deep inspirations on material composition and color planning for fashion design focused on colors. Additionally, needle-punching technique using wool for the production technique enabled relief texture expressions of materials by colors and effective applications of soft and warm atmosphere of color-field abstract of Rothko on clothing. Especially, the ideology of color-field abstract of Rothko of shaping of colors could be expressed and the direction of the development of motives could be presented at the same time by specifically applying color combination method using horizontal division of atypical color-field from the formative characteristics of color-field abstract of Rothko.

  • PDF

Clinical Experience of Silicone Airway Stent in the Management of Benign Tracheobronchial Stenosis (양성 기도협착질환에서 실리콘 기도스텐트의 임상경험 - Dumon 스텐트와 Natural 스텐트의 비교 -)

  • Ryu, Yon Ju;Yu, Chang-Min;Choi, Jae Chul;Kwon, Yong Soo;Kim, Hojoong;Kim, Jhingook;Suh, Soo Won
    • Tuberculosis and Respiratory Diseases
    • /
    • v.59 no.1
    • /
    • pp.62-68
    • /
    • 2005
  • Background : The clinical results of a Natural stent in patients with a benign tracheobronchial stenosis were examined by comparing the clinical outcomes and complications of those patients who underwent Dumon and Natural stenting in the management of benign airway stenosis. Methods : The medical records of 94 patients (39 Dumon and 55 Natural stent) with a benign tracheobronchial stenosis were reviewed and analyzed. Results : Post-tuberculous stenosis was the leading indication for airway stenting (74%), which was followed by post-intubation stenosis (21%). After intervention, the dyspnea had improved among those patients who underwent Dumon (90%) and Natural (86%) stenting. After stabilizing the dyspnea, the stent could be successfully removed in half of the patients who underwent both Dumon (54%) and Natural (49%) stenting. During the 42 month follow-up period, the complication rate was similar in those patients who underwent Dumon and Natural stenting: migration (46% vs 53%), granulation tissue formation (36% vs 49%), mucostasis (21% vs 16%) and restenosis (51% vs 36%). Conclusion : The clinical results of Natural airway stent was similar to those of Dumon stent in the management of benign tracheobronchial stenosis.

The Effect of Remifentanil Preconditioning on Injured Keratinocyte

  • Hong, Hun Pyo;Kim, Cheul Hong;Yoon, Ji Young;Kim, Yong Deok;Park, Bong Soo;Kim, Yong Ho;Yoo, Ji Uk
    • Journal of The Korean Dental Society of Anesthesiology
    • /
    • v.14 no.3
    • /
    • pp.157-165
    • /
    • 2014
  • Background: Incisional site of surgical operation become transient ischemic state and then occur reoxygenation due to vasodilatation by inflammatory reaction, the productive reactive oxygen species (ROS) give rise to many physiologic results. Apoptosis have major role on elimination of inflammatory cell and formation of granulation tissue in normal wound healing process. Remifentanil can prevent the inflammatory response and can suppress inducible nitric oxide synthase expression in a septic mouse model. After cardiopulmonary bypass for coronary artery surgery, remifentanil can also inhibit the release of biomarkers of myocardial damage. Here we investigated whether remifentanil pretreatment has cellular protective effect against hypoxia-reoxygenation in HaCaT human keratinocytes, if so, the role of apoptosis and autophagy on this phenomenon. Methods: The HaCaT human keratinocytes were exposed to various concentrations of remifentanil (0.01, 0.05, 0.1, 0.5 and 1 ng/ml) for 2 h before hypoxia (RPC/HR group). These cells were cultured under 1% oxygen tension for 24h at $37^{\circ}C$. After hypoxia, to simulate reoxygenation and recovery, the cells were reoxygenated for 12 h at $37^{\circ}C$. 3-MA/RPC/HR group was treated 3-methyladenine (3-MA), autophagy inhibitor for 1h before remifentanil treatment. Cell viability was measured using a quantitative colorimetric assay with thiazolyl blue tetrazoliumbromide (MTT, amresco), showing the mitochondrial activity of living cells. To investigate whether the occurrence of autophagy and apoptosis, we used fluorescence microscopy and Western blot analysis. Results: The viability against hypoxia-reoxygenation injury in remifentanil preconditioning keratinocytes were increased, and these cells were showed stimulated expression of autophagy 3-MA suppressed the induction of autophagy effectively and the protective effects on apoptosis. Atg5, Beclin-1, LC3-II and p62 were elevated in RPC/HR group. But they were decreased when autophagy was suppressed by 3-MA. Conclusions: Remifentanil preconditioning showed the protective effect in human keratinocytes, and we concluded that autophagy may take the major role in the recovery of wound from hypoxia-reoxygenation injury. We suggest that further research is needed about the cell protective effects of autophagy.

Surface Ozone Episode Due to Stratosphere-Troposphere Exchange and Free Troposphere-Boundary Layer Exchange in Busan During Asian Dust Events

  • Moon, Y.S.;Kim, Y.K.;K. Strong;Kim, S.H.;Lim, Y.K.;Oh, I.B.;Song, S.K.
    • Journal of Environmental Science International
    • /
    • v.11 no.5
    • /
    • pp.419-436
    • /
    • 2002
  • The current paper reports on the enhancement of O$_3$, CO, NO$_2$, and aerosols during the Asian dust event that occurred over Korea on 1 May 1999. To confirm the origin and net flux of the O$_3$, CO, NO$_2$, and aerosols, the meteorological parameters of the weather conditions were investigated using Mesoscale Meteorological Model 5(MM5) and the TOMS total ozone and aerosol index, the back trajectory was identified using the Hybrid Single-Particle Lagrangian Integrated Trajectory Model(HYSPLIT), and the ozone and ozone precursor concentrations were determined using the Urban Ashed Model(UAM). In the presence of sufficiently large concentrations of NO$\sub$x/, the oxidation of CO led to O$_3$ formation with OH, HO$_2$, NO, and NO$_2$ acting as catalysts. The sudden enhancement of O$_3$, CO, NO$_2$ and aerosols was also found to be associated with a deepening cut-off low connected with a surface cyclone and surface anticyclone located to the south of Korea during the Asian dust event. The wave pattern of the upper trough/cut-off low and total ozone level remained stationary when they came into contact with a surface cyclone during the Asian dust event. A typical example of a stratosphere-troposphere exchange(STE) of ozone was demonstrated by tropopause folding due to the jet stream. As such, the secondary maxima of ozone above 80 ppbv that occurred at night in Busan, Korea on 1 May 2001 were considered to result from vertical mixing and advection from a free troposphere-boundary layer exchange in connection with an STE in the upper troposphere. Whereas the sudden enhancement of ozone above 100 ppbv during the day was explained by the catalytic reaction of ozone precursors and transport of ozone from a slow-moving anticyclone area that included a high level of ozone and its precursors coming from China to the south of Korea. The aerosols identified in the free troposphere over Busan, Korea on 1 May 1999 originated from the Taklamakan and Gobi deserts across the Yellow River. In particular, the 1000m profile indicated that the source of the air parcels was from an anticyclone located to the south of Korea. The net flux due to the first invasion of ozone between 0000 LST and 0600 LST on 1 May 1999 agreed with the observed ground-based background concentration of ozone. From 0600 LST to 1200 LST, the net flux of the second invasion of ozone was twice as much as the day before. In this case, a change in the horizontal wind direction may have been responsible for the ozone increase.

AN EXPERIMENTAL STUDY FOR THE DETECTION OF AUTOCRINE GROWTH ACTIVITY IN THE OSTEOGENIC CELLS AFTER MANDIBULAR DISTRACTION OSTEOGENESIS (하악골 신장술 후 신생골 조직에서 자가분비성장능력의 활성에 대한 실험적 연구)

  • Byun, June-Ho;Park, Bong-Wook;Park, Seong-Cheol;Kim, Gyoo-Cheon;Park, Bong-Soo;Kim, Jong-Ryoul
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
    • /
    • v.33 no.4
    • /
    • pp.331-339
    • /
    • 2007
  • Background: Distraction osteogenesis(DO) is a useful method for treating cases demanding the generation of new bone. During DO, the angiogenic activity is crucial factor in the new bone formation. The aim of this study was to detect the autocrine growth activity in the cellular components of the distracted bone with observation of the co-expression of vascular endothelial growth factor(VEGF) and its receptors following the mandibular DO. Materials and methods: Unilateral mandibular distraction(0.5 mm twice per day for 10 days) was performed in six mongrel dogs. Two animals were killed at 7, 14, and 28 days after completion of distraction, respectively. Immediately after the animals were killed, the right mandibles were harvested en block. Immunohistochemical staining was processed for observation of the VEGF expression, and double immunofluorescent staining was also processed for detection of the co-expression of osteocalcin and VEGF's two distinct receptors(VEGFR-1 and VEGFR-2). Results: At 7 and 14 days after distraction, the expressions of VEGF were significantly increased in the osteogenic cells of the distracted bone. Up to 28 days after distraction, VEGF was still expressed moderate in the osteoblastic cells of distracted bone. The co-expressions of osteocalcin/VEGFR-1 and osteocalcin/VEGFR-2 were observed in the distracted bone at 7 and 14 days after distraction. In the double immunofluorescent staining, the co-expression' s level of osteocalcin/VEGFR-1 was more than that of osteocalcin/VEGFR-2. Conclusion: Taken together, this study suggested that VEGF plays an important role in the osteogenesis, and these osteoblastic cell-derived VEGF might act as autocrine growth factor during distraction osteogenesis. In the other word, the cellular components, such as osteoblasts and immature fibroblast-like cellsor mesenchymal cells in the distracted bone, might have autocrine growth activity during distraction osteogenesis.

Clinical, histologic, and histometric evaluation of implants with microthreaded crest module and SLA surface (SLA로 표면처리한 microthreaded crest module 임프란트의 임상적, 조직학적, 조직계측학적 분석)

  • Moon, Sang-Kwon;Pang, Eun-Kyoung;Kim, Chang-Sung;Cho, Kyoo-Sung;Chai, Jung-Kiu;Kim, Chong-Kwan;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
    • /
    • v.34 no.1
    • /
    • pp.127-138
    • /
    • 2004
  • Background: Crestal bone loss known as saucerization is a frequently observed phenomenon. Recent studies have shown that implants with micothreaded crest module reduced the force concentration in the crestal region thus resulting in no or reduced crestal bone loss. This study presents a clinical, histologic, and histometric evaluation of implants with microthreaded crest module and SLA surface. Methods: The implants were placed in the mandible of 5 beagle dogs weighing 10-15kg. Four premolars were bilaterally extracted 8 weeks prior to implant placement. Mucoperiosteal flap was elevated and drilling with increasing diameter was performed under saline irrigation. After countersinking 2 implants were placed in each side resulting in 4 implants per dog. Healing period of 8 weeks was allowed before sacrificing the animals. Histologic preparation was performed for histologic and histometric analysis. Bone to implant contact as well as percentage of bone area inside threads were measured. T-test was used for statistical analysis with pvalue p<0.05. Results: 1. Healing was uneventful without any cover screw exposure. New bone formation around the implants was observed without any inflammatory infiltration. 2. Bone to implant contact in the microthread and thread were 43.90 ${\pm}$ 20.30 %, and 53.19 ${\pm}$ 20.97 % respectively. The overall bone to implant contact was 48.54 ${\pm}$ 20.95 %. 3. Percentage of bone area inside threads were 54.43 ${\pm}$ 10.39 %, and 38.44 ${\pm}$ 16.44 % for the microthread and thread respectively. There was statistically significant difference(p<0.05). The overall percentage of bone area inside threads was 46.67 ${\pm}$ 15.68 %.

The Role of Dynamic CT for the Differential Diagnosis of Solitary Pulmonary Nodule (고립성 폐결절의 감별진단에서 Dynamic CT의 역할)

  • Chung, Jin-Hong;Park, Won-Jong;Cho, Ihn-Ho
    • Journal of Yeungnam Medical Science
    • /
    • v.25 no.2
    • /
    • pp.102-107
    • /
    • 2008
  • Background : Malignant pulmonary nodules account for 30 to 40 percent of all solitary pulmonary nodules (SPNs). Therefore, characterization of SPNs is very important for treatment. Recently, dynamic CT has been widely used for tissue characterization and formation of differential diagnoses. The purpose of this study was to evaluate the ability of dynamic CT to formulate the differential diagnosis of SPNs. Materials and Methods : Nineteen patients with SPNs underwent dynamic CT (unenhanced scans, followed by a series of images at 20, 40, 60, 80, 100, 120, 140, 160, and 180 sec after intravenous injection of contrast medium). Diagnosis of SPN was performed based on pathologic findings in needle biopsy samples. Peak enhancement, net enhancement, slope of enhancement, and maximum relative enhancement ratio of the SPN were measured on dynamic CT, and Levene's test was performed to assess benignancy and malignancy. Results : Twelve SPNs were confirmed to have malignant pathology. There were no significant differences between benign and malignant nodules with respect to peak enhancement (p=0.787), net enhancement (p=0.135), or slope of enhancement (p=0.698). The maximal enhancement ratio was increased in malignancy compared to benignancy, but the difference was not statistically significant (p=0.094). Conclusion : In our study, the hemodynamic characteristics of dynamic CT were not significantly different between benign and malignant nodules. Therefore, long-term studies of larger patient samples are required to confirm our findings.

  • PDF

Senescence as A Consequence of Ginsenoside Rg1 Response on K562 Human Leukemia Cell Line

  • Liu, Jun;Cai, Shi-Zhong;Zhou, Yue;Zhang, Xian-Ping;Liu, Dian-Feng;Jiang, Rong;Wang, Ya-Ping
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.13 no.12
    • /
    • pp.6191-6196
    • /
    • 2012
  • Aims and Background: Traditional chemotherapy strategies for human leukemia commonly use drugs based on cytotoxicity to eradicate cancer cells. One predicament is that substantial damage to normal tissues is likely to occur in the course of standard treatments. Obviously, it is urgent to explore therapies that can effectively eliminate malignant cells without affecting normal cells. Our previous studies indicated that ginsenoside $Rg_1$ ($Rg_1$), a major active pharmacological ingredient of ginseng, could delay normal hematopoietic stem cell senescence. However, whether $Rg_1$ can induce cancer cell senescence is still unclear. Methods: In the current study, human leukemia K562 cells were subjected to $Rg_1$ exposure. The optimal drug concentration and duration with K562 cells was obtained by MTT colorimetric test. Effects of $Rg_1$ on cell cycle were analyzed using flow cytometry and by SA-${\beta}$-Gal staining. Colony-forming ability was measured by colony-assay. Telomere lengths were assessed by Southern blotting and expression of senescence-associated proteins P21, P16 and RB by Western blotting. Ultrastructural morphology changes were observed by transmission electron microscopy. Results: K562 cells demonstrated a maximum proliferation inhibition rate with an $Rg_1$ concentration of $20{\mu}\;mol{\cdot}L^{-1}$ for 48h, the cells exhibiting dramatic morphological alterations including an enlarged and flat cellular morphology, larger mitochondria and increased number of lysosomes. Senescence associated-${\beta}$-galactosidase (SA-${\beta}$-Gal) activity was increased. K562 cells also had decreased ability for colony formation, and shortened telomere length as well as reduction of proliferating potential and arrestin $G_2$/M phase after $Rg_1$ interaction. The senescence associated proteins P21, P16 and RB were significantly up-regulated. Conclusion: Ginsenoside $Rg_1$ can induce a state of senescence in human leukemia K562 cells, which is associated with p21-Rb and p16-Rb pathways.

A Study on the Satisfaction and Achievement of Learning by Female Learner's Characteristics in Internet Education Program (여성 학습자의 특성에 따른 인터넷교육 프로그램 만족도와 학업성취도에 관한 연구)

  • Lim, Kwang Myung;Kim, Sung Soo
    • Journal of Agricultural Extension & Community Development
    • /
    • v.8 no.1
    • /
    • pp.25-40
    • /
    • 2001
  • The purposes of the study were to identify satisfaction and achievement of learning by female learner's characteristics, and to suggest measures to improve quality of education in internet education programs. In order to determine the educational effectiveness associated with the characteristics of learners, this study attempted to employ two way approaches by observing the degree of achievement for learning, which represents an instructor-oriented approach, and the degree of satisfaction for education, which represents a learner-oriented approach to enhance the quality of internet education for female learners. As an approach to evaluate the educational effectiveness, the degree of achievement in learning(Tyler's classical approach), and the degree of satisfaction for education (Scriven's consumer-oriented evaluation model) were utilized. A survey form was developed by the researcher after reviewing the various tools originated from Boshier, Cross, Gagne and Choi, and distributed to a panel of judges that examined the content validity of the instrument. The sample for the study consisted of 160 female learners from three universities in Seoul and capital area, and the survey form was used to collect data for this study. The SPSS WIN program was used in analyzing the data and a series of statistical tests were conducted including frequency, percentile, t-test, ANOVA, correlation, multiple regression, and factor analysis. The statistical significance level was 0.05. The following conclusion were drawn from this study of female internet education. First, it was evident that female internet learners tend to utilize information from internet, and this can be interpreted as participants' positive attitude, and voluntary participation. Second, educational facilities and services should be improved in the future, because the level of satisfaction was low in these areas compared to curriculum and educational methodology. Third, the participating factors influenced by the level of satisfaction for education of learner characteristics were the 'formation of inter-personal relationship and willingness to change' and the 'needs for education on internet', thus appeared that both social and educational needs influenced the level of satisfaction for education. Fourth, the degree of achievement in learning was higher in the order of 1) attitude 2) function 3) knowledge, thus, attitude change was the most important in achievement of learning. Fifth, the individual background that influenced the level of achievement in learning were age and educational experience. As for the individual level of achievement for learning, the younger and more educated group were more satisfied.

  • PDF