• Title/Summary/Keyword: Background Modeling

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Kinetic analysis of 64Cu-NODAGA-gluco-E[c(RGDfK)]2 for a tumor angiogenesis PET tracer

  • Choi, Jae Yong;Park, Ji-Ae;Kim, Jung Young;Lee, Ji Woong;Lee, Minkyung;Shin, Un Chol;Kang, Joo Hyun;An, Gwang Il;Lee, Kyo Chul;Ryu, Young Hoon;Kim, Kyeong Min
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.2 no.2
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    • pp.108-112
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    • 2016
  • Molecular imaging with the radiolabeled RGD peptides for ${\alpha}_v{\beta}_3$ integrin has been an increasing interest for tumor diagnosis and the treatment monitoring. Recently, $^{64}Cu$-NODAGA-gluco-E[c(RGDfK)]$_2$ was developed for quantification of ${\alpha}_v{\beta}_3$ integrin and its biological properties was elucidated. To better understand the molecular process in vivo, we performed the kinetic analysis for the $^{64}Cu$-NODAGA-gluco-E[c(RGDfK)]$_2$. After preparation of a radiotracer, dynamic PET images were obtained in the U87MG xenograft mice for 60 min (n = 6). Binding potential values were estimated from the 3-tissue compartment model, reference Logan and simplified reference tissue model. In the early time frame (0-20 min), the liver, kidney, intestine, urinary bladder and tumor were visualized but these uptakes were diminished as time went by. The tumors showed a good contrast at 40 min after administration. $^{64}Cu$-NODAGA-gluco-E[c(RGDfK)]$_2$ showed the 2-fold uptake in the tumor compared with that in the muscle. The parametric maps for binding values also provide the higher tumor-to-background contrast than the static images. A binding value obtained from the 3-tissue compartment model was comparable to other modeling methods. From these results, we conclude that $^{64}Cu$-NODAGA-gluco-E[c(RGDfK)]$_2$ may be a promising PET radiotracer for the evaluation of angiogenesis.

Reactivation of Silenced WT1 Transgene by Hypomethylating Agents - Implications for in vitro Modeling of Chemoimmunotherapy

  • Kwon, Yong-Rim;Son, Min-Jung;Kim, Hye-Jung;Kim, Yoo-Jin
    • IMMUNE NETWORK
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    • v.12 no.2
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    • pp.58-65
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    • 2012
  • Background: A cell line with transfected Wilms' tumor protein 1 (WT1) is has been used for the preclinical evaluation of novel treatment strategies of WT1 immunotherapy for leukemia due to the lack of appropriate murine leukemia cell line with endogenous WT1. However, silencing of the transgene occurs. Regarding the effects of hypomethylating agents (HMAs) on reactivation of silenced genes, HMAs are considered to be immune enhancers. Methods: We treated murine WT1- transfected C1498 (mWT1-C1498) with increasing doses of decitabine (DAC) and azacitidine (AZA) to analyze their effects on transgene reactivation. Results: DAC and AZA decreased the number of viable cells in a dose- or time-dependent manner. Quantification of WT1 mRNA level was analyzed by real-time polymerase chain reaction after mWT1-C1498 treated with increasing dose of HMA. DAC treatment for 48 h induced 1.4-, 14.6-, and 15.5-fold increment of WT1 mRNA level, compared to untreated sample, at 0.1, 1, and $10{\mu}M$, respectively. Further increment of WT1 expression in the presence of 1 and $10{\mu}M$ DAC was evident at 72 h. AZA treatment also induced up-regulation of mRNA, but not to the same degree as with DAC treatment. The correlation between the incremental increases in WT1 mRNA by DAC was confirmed by Western blot and concomitant down-regulation of WT1 promoter methylation was revealed. Conclusion: The in vitro data show that HMA can induce reactivation of WT1 transgene and that DAC is more effective, at least in mWT1-C1498 cells, which suggests that the combination of DAC and mWT1-C1498 can be used for the development of the experimental model of HMA-combined WT1 immunotherapy targeting leukemia.

Impact of RGD Peptide Tethering to IL24/mda-7 (Melanoma Differentiation Associated Gene-7) on Apoptosis Induction in Hepatocellular Carcinoma Cells

  • Bina, Samaneh;Shenavar, Fatemeh;Khodadad, Mahboobeh;Haghshenas, Mohammad Reza;Mortazavi, Mojtaba;Fattahi, Mohammad-Reza;Erfani, Nasrollah;Hosseini, Seyed Younes
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.14
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    • pp.6073-6080
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    • 2015
  • Background: Melanoma differentiation-associated gene-7 (MDA-7)/interleukin-24 (IL-24), a unique tumor suppressor gene, has killing activity in a broad spectrum of cancer cells. Herein, plasmids producing mda-7 proteins fused to different RGD peptides (full RGD4C and shortened RGD, tRGD) were evaluated for apoptosis induction with a hepatocellular carcinoma cell line, Hep-G2. The study aim was to improve the apoptosis potency of mda-7 by tethering to RGD peptides. Materials and Methods: Three plasmids including mda-7, mda-7-RGD and mda-7-tRGD genes beside a control vector were transfected into Hep-G2 cells. After 72 hours incubation, cell viability was evaluated by MTT assay. In addition, the rate of apoptosis was analyzed by flow cytometry using PI/annexin staining. To detect early events in apoptosis, 18 hours after transfection, expression of the BAX gene was quantified by real time PCR. Modeling of proteins was also performed to extrapolate possible consequences of RGD modification on their structures and subsequent attachment to receptors. Results and Conclusions: In MTT assays, while all mda-7 forms showed measurable inhibition of proliferation, unmodified mda-7 protein exhibited most significant effect compared to control plasmid (P<0.001). Again, flow cytometry analysis showed a significant apoptosis induction by simple mda-7 gene but not for those RGD-fused mda-7 proteins. These findings were also supported by expression analysis of BAX gene (P<0.001). Protein modelling analysis revealed that tethering RGD at the end of IL-24/Mda7 disrupt attachment to cognate receptor, IL-20R1/IL-20R2. In conclusion, fusion of RGD4C and shortened RGD peptides to carboxyl terminal of mda7, not only reduce apoptosis property in vitro but also disrupt receptor attachment as demonstrated by protein modelling.

Clinicopathological Features and Prognosis of Gastroenteropancreatic Neuroendocrine Tumors: Analysis from a Single-institution

  • Zeng, Yu-Jie;Liu, Lu;Wu, Heng;Lai, Wei;Cao, Jie-Zhi;Xu, He-Yang;Wang, Jie;Chu, Zhong-Hua
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.10
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    • pp.5775-5781
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    • 2013
  • Background: The gastroenteropancreatic neuroendocrine neoplasm (GEP-NEN) is the most common type of neuroendocrine neoplasm. We summarized data in our centre to investigate the clinicopathological features, diagnostic methods, therapeutic approaches and prognosis for this neoplasm to increase knowledge of this disease in Asian populations. Method: A total of 122 patients treated at Sun Yet-san Memorial Hospital of Sun Yat-sen University between January 2000 and December 2011 were analyzed retrospectively. Results: Pancreas was the most common site of involvement (65/122, 53.3%); this disease has no special symptoms; positive rates of chromogranin A (CgA) and synaptophysin (Syn) were 81.1% and 87.7%, respectively. The positive rate of Syn had statistical difference among the three grades, but not CgA. Some 68 patients had G1 tumors, 32 G2 tumors and 22 G3 tumors, and Chi-square test showed that higher grading was correlated with worse prognosis (${\chi}^2=32.825$, P=0.0001). A total of 32 patients presented with distant metastasis, and 8 cases emerged during following up. Cox proportional hazards regression modeling showed that the tumor grade (P=0.01), lymphatic metastasis (P=0.025) and distant metastasis (P=0.031) were predictors of unfavorable prognosis. The overall 5-year survival rate was 39.6%, the 5-year survival rate of G1 was 55.7%, and the G2 and G3 were 34.2% and 0%, respectively. Conclusions: The incidence of gastroenteropancreatic neuroendocrine tumors has risen over the last 12 years. All grades of these diseases metastasize readily, and further research regarding the treatment of patients after radical surgery is needed to prolong disease-free survival.

Blood Malignancies in Mazandaran Province of Iran

  • Tahmasby, Bahram;Marnani, Ahmad Barati;Maleki, Mohammadreza;Barouni, Mohsen;Mousavi, Seyyed Hamid;Naseriyan, Behjat;Nazarnezhad, Mirzaali;Alizadeh, Ali;Sabermahani, Asma
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.2
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    • pp.1053-1056
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    • 2013
  • Background: Leukemia and lymphoma demonstrate significantly incidence rates throughout the world and particularly in Iran they cause serious mortality and diagnosis and treatment expenditures for both families and the health system. Combined they account for about 11 percent of cancers in Mazandaran province, ranking number 2 in prevalent cancers. The purpose of this study was to provide a first general and specific description of leukemia and lymphoma in Mazandaran province. Materials and Methods: In this descriptive retrospective study, entire patient's data were reviewed which had confirmed diagnosis of leukemia and lymphoma with valid laboratory or pathology reports in the period 2001-2008. The data were collected by Babol health research site related to Tehran University of Medical Science. Incidence rates based on age groups, gender, city of residence and type of malignancy were calculated and analyzed. Results: In Mazandaran province, 1,146 cases of leukemia and lymphoma were encountered, 5.9 in 100,000 persons on average annually. The highest incidence rates were obtained at age of 70 or above (26.4) and the lowest at age of 0-9 (2.3).The incidence rates in males and females were 7.1 and 4.8 respectively with a ratio of 1.5. The highest incidence rate was in Babol (7.3) and the lowest was calculated in Neka and Tonekabon equally (1.5). According to the type of malignancy, non Hodgkin lymphoma, with 2.5/100,000 have the most incidence rate and myeloid leukemia with 1.8 had the lowest. Conclusions: The obtained findings indicate clear differences in incidence rates based on age, gender, residence, and type of malignancy. Therefore it's suggested that in addition to promote data collecting programs, research projects should be programmed to define leukemia and lymphoma risk factors in this province.

Face Detection in Color Images Based on Skin Region Segmentation and Neural Network (피부 영역 분할과 신경 회로망에 기반한 칼라 영상에서 얼굴 검출)

  • Lee, Young-Sook;Kim, Young-Bong
    • The Journal of the Korea Contents Association
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    • v.6 no.12
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    • pp.1-11
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    • 2006
  • Many research demonstrations and commercial applications have been tried to develop face detection and recognition systems. Human face detection plays an important role in applications such as access control and video surveillance, human computer interface, identity authentication, etc. There are some special problems such as a face connected with background, faces connected via the skin color, and a face divided into several small parts after skin region segmentation in generally. It can be allowed many face detection techniques to solve the first and second problems. However, it is not easy to detect a face divided into several parts of regions for reason of different illumination conditions in the third problem. Therefore, we propose an efficient modified skin segmentation algorithm to solve this problem because the typical region segmentation algorithm can not be used to. Our algorithm detects skin regions over the entire image, and then generates face candidate regions using our skin segmentation algorithm For each face candidate, we implement the procedure of region merging for divided regions in order to make a region using adjacency between homogeneous regions. We utilize various different searching window sizes to detect different size faces and a face detection classifier based on a back-propagation algorithm in order to verify whether the searching window contains a face or not.

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3D Product digital camera Model on the Web and study about developing 3D shopping mall (Web 상에서 3차원 디지털카메라제품모델과 3차원 쇼핑몰 개발에 관한 연구)

  • 조진희;이규옥
    • Archives of design research
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    • v.14 no.1
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    • pp.63-70
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    • 2001
  • Thanks to the inter-connection of information servers throughout the world based on the internet technology, the new sphere which actual transaction can be made like in the visible market has become conspicuous as the virtual space. The movement to realize the new business through the cyber space has been actively ongoing. In the domestic market, a lot of corporations knowing the needs of internet shopping malls have entered into this e-business but they have not made a big success comparing with internet's potentials. And, it can be attributed to the simple planes and the limitations of information provided by the cyber malls, which means that the needs of better information transfer we apparent Accordingly, in this thesis, the research on the 3-D based products and shopping malls has been made through the inter-complementary composition between the 2-D shopping malls and 3-B ones. This research consists of 3 parts. Firstly, through the research on references and existing data, it presents the analysis on consumer's characteristics and sales limits of the internet shopping mall's products. Secondly, the background of 3-D shopping mall's advent and the virtual reality technology data are put together. Finally, it presents how the development of 3-D based product modeling and shopping malls can increase the consumer's purchase power and furthermore the directions of shopping malls to go.

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Seismic Responses Control of Coupled Shear Wall Structures Using LRBs (LRB를 이용한 병렬전단벽 구조물의 지진응답제어)

  • Park, Yong-Koo;Kim, Hyun-Su;Ko, Hyun;Kim, Min-Gyun;Lee, Dong-Guen
    • Journal of the Earthquake Engineering Society of Korea
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    • v.14 no.6
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    • pp.1-9
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    • 2010
  • Most of shear wall structures require openings in shear walls and thus shear walls are linked by floor slabs or coupling beams resulting in the coupled shear wall structures. When these structures are subjected to seismic excitations, excessive shear forces are induced in coupling beams. Accordingly, brittle failure of coupling beams may occur or shear walls may yield first. To avoid this problem, damping devices can be installed in coupling beams. It can increase the vibration control effect and improve the seismic resistance performance of the coupled shear wall structure by avoiding stress concentration and the brittle failure of coupling beams. Based on this background research, an LRB (lead rubber bearing) was introduced in the middle of the coupling beam in this study and the authors investigated the seismic response control effect and stress distribution of the proposed system. To this end, a modeling technique that can effectively predict the structural behavior of coupled shear wall structures has been proposed. With this proposed technique, time history analyses of the example coupled shear wall structure subjected to seismic excitation were performed and the vibration control effects of the seismic responses were investigated.

Atmospheric Dispersion Characteristics of Radioactive Materials according to the Local Weather and Emission Conditions

  • An, Hye Yeon;Kang, Yoon-Hee;Song, Sang-Keun;Kim, Yoo-Keun
    • Journal of Radiation Protection and Research
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    • v.41 no.4
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    • pp.315-327
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    • 2016
  • Background: This study evaluated the atmospheric dispersion of radioactive material according to local weather conditions and emission conditions. Materials and Methods: Local weather conditions were defined as 8 patterns that frequently occur around the Kori Nuclear Power Plant and emission conditions were defined as 6 patterns from a combination of emission rates and the total number of particles of the $^{137}Cs$, using the WRF/HYSPLIT modeling system. Results and Discussion: The highest mean concentration of $^{137}Cs$ occurred at 0900 LST under the ME4_1 (main wind direction: SSW, daily average wind speed: $2.8ms^{-1}$), with a wide region of its high concentration due to the continuous wind changes between 0000 and 0900 LST; under the ME3 (NE, $4.1ms^{-1}$), the highest mean concentration of $^{137}Cs$ occurred at 1500 and 2100 LST with a narrow dispersion along a strong northeasterly wind. In the case of ME4_4 (S, $2.7ms^{-1}$), the highest mean concentration of $^{137}Cs$ occurred at 0300 LST because $^{137}Cs$ stayed around the KNPP under low wind speed and low boundary layer height. As for the emission conditions, EM1_3 and EM2_3 that had the maximum total number of particles showed the widest dispersion of $^{137}Cs$, while its highest mean concentration was estimated under the EM1_1 considering the relatively narrow dispersion and high emission rate. Conclusion: This study showed that even though an area may be located within the same radius around the Kori Nuclear Power Plant, the distribution and levels of $^{137}Cs$ concentration vary according to the change in time and space of weather conditions (the altitude of the atmospheric boundary layer, the horizontal and vertical distribution of the local winds, and the precipitation levels), the topography of the regions where $^{137}Cs$ is dispersed, the emission rate of $^{137}Cs$, and the number of emitted particles.

Optimal Density Assignment to 2D Diode Array Detector for Different Dose Calculation Algorithms in Patient Specific VMAT QA

  • Park, So-Yeon;Park, Jong Min;Choi, Chang Heon;Chun, Minsoo;Han, Ji Hye;Cho, Jin Dong;Kim, Jung-in
    • Journal of Radiation Protection and Research
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    • v.42 no.1
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    • pp.9-15
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    • 2017
  • Background: The purpose of this study is to assign an appropriate density to virtual phantom for 2D diode array detector with different dose calculation algorithms to guarantee the accuracy of patient-specific QA. Materials and Methods: Ten VMAT plans with 6 MV photon beam and ten VMAT plans with 15 MV photon beam were selected retrospectively. The computed tomography (CT) images of MapCHECK2 with MapPHAN were acquired to design the virtual phantom images. For all plans, dose distributions were calculated for the virtual phantoms with four different materials by AAA and AXB algorithms. The four materials were polystyrene, 455 HU, Jursinic phantom, and PVC. Passing rates for several gamma criteria were calculated by comparing the measured dose distribution with calculated dose distributions of four materials. Results and Discussion: For validation of AXB modeling in clinic, the mean percentages of agreement in the cases of dose difference criteria of 1.0% and 2.0% for 6 MV were $97.2%{\pm}2.3%$, and $99.4%{\pm}1.1%$, respectively while those for 15 MV were $98.5%{\pm}0.85%$ and $99.8%{\pm}0.2%$, respectively. In the case of 2%/2 mm, all mean passing rates were more than 96.0% and 97.2% for 6 MV and 15 MV, respectively, regardless of the virtual phantoms of different materials and dose calculation algorithms. The passing rates in all criteria slightly increased for AXB as well as AAA when using 455 HU rather than polystyrene. Conclusion: The virtual phantom which had a 455 HU values showed high passing rates for all gamma criteria. To guarantee the accuracy of patent-specific VMAT QA, each institution should fine-tune the mass density or HU values of this device.