• Asian Pacific Journal of Cancer Prevention
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• v.15 no.9
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• pp.3921-3925
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• 2014

RASSF1A has been reported to be a candidate tumor suppressor in esophageal squamous cell carcinoma (ESCC). However, the association between RASSF1A promoter methylation and ESCC remains unclear. Eligible studies were identified through searching PubMed, Medline, Web of Science, and the China National Knowledge Infrastucture database. Studies were pooled and odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated. Funnel plots were also performed to evaluate publication bias. Twelve studies involving 859 cases and 675 controls were included in this meta-analysis. A significant association was observed between RASSF1A methylation and ESCC overall (OR = 11.7, 95% CI: 6.59-20.9, z=8.36, P<0.00001). Subgroup analysis showed that the OR for heterogeneous tissues was 5.35 (95% CI = 2.95-9.71) while for autologous tissues it was 16.0 (8.31-30.96). For patient sample size, the OR for the <50 subgroup was 9.92 (95% CI = 2.88-34.2) and for the 50 case group was 13.1 (95% CI = 6.59-25.91). The OR for a relationship between RASSF1A methylation and TNM stages was 0.27 (95% CI=0.10-0.77), whereas there were no significant differences in RASSF1A methylation in relation to gender and differentiation among ESCC cases. This meta-analysis suggests a significant association between RASSF1A methylation and ESCC.

• BMB Reports
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• v.39 no.2
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• pp.171-177
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• 2006

Nonsteroidal anti-inflammatory drugs such as indomethacin (IN) can exert anti-colorectal cancer (CRC) activity through cyclooxygenase independent mechanism, but the exactly biological mechanism is not completely known. Here we use proteomic tools to investigate the molecular mechanism of this action. First, nude mice bearing tumors derived from subcutaneous injection with human CRC cell line HCT116 were randomly allocated to groups treated with or without indomethacin. Later, tumor lumps were incised and then total proteins extracted. After separated with two-dimensional electrophoresis, thirty-one differently expressed spots were found between IN-treated and non-IN-treated groups, of which 25 spots decreased and 6 spots increased in abundance in IN-treated group. Through matrix-assisted laser desorption ionization time of flight mass spectrometry and then NCBInr and SWISS-PROT databases searching, 12 protein spots were finally identified including galectin-1, annexin A1, annexin IV, trancription factor BTF3A, calreticulin. Most of the identified proteins are correlated with tumor's biological prosperities of proliferation, invasion, apoptosis and immunity, or take part in cell's signal transduction. From above we thought that indomethacin can exert its effect on colorectal cancer through regulating several proteins' expression directly or indirectly. Further study of these proteins may be helpful in founding new targets of drugs for cancer chemotherapy.

• Journal of Life Science
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• v.12 no.2
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• pp.219-225
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• 2002

The organization of eukayotic chromatin into specific conformation that are associated with transcription, replication, reapir and other nuclear processes are achieved via a series of DNA-protein interaction. These interactions are mediated by a range of DNA-binding domains such as SAP domain et at. By searching S. pombe genomic DNA database, we have found a gene named SAPuvs (SAP UV Sensitive) whose amino acid sequence is in part similar to SAP domain of Arabidopsis poly (ADP-ribose) polymerase and Ku7O. Knock-out cell of S. pombe SAPuvs gene was constructed using Ura4 as a selection marker. Survival analysis of knock-out cell indicated that treatment with UV significantly reduces the survival compared to wild type cell. Potentiation of MMS-induced cytotoxicity by 3AB post-treatment was observed in wild type cells, but not in knock-out cells. These data suggested that the protein encoded by SAPuvs gene is associated with chromatin reorganization during DNA repair.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.6
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• pp.1828-1847
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• 2014

Coordinated multi-point (CoMP) transmission has been regarded as a potential technology for LTE-Advanced. In frequency division duplexing systems, channel quantization is applied for reporting channel state information (CSI). Considering the dynamic number of cooperation base stations (BSs), asymmetry feature of CoMP channels and high searching complexity, simply increasing the size of the codebook used in traditional multiple antenna systems to quantize the global CSI of CoMP systems directly is infeasible. Per-cell codebook based channel quantization to quantize local CSI for each BS separately is an effective method. In this paper, the theoretical upper bounds of system throughput are derived for two codeword selection schemes, independent codeword selection (ICS) and joint codeword selection (JCS), respectively. The feedback overhead and selection complexity of these two schemes are analyzed. In the simulation, the system throughput of ICS and JCS is compared. Both analysis and simulation results show that JCS has a better tradeoff between system throughput and feedback overhead. The ICS has obvious advantage in complexity, but it needs additional phase information (PI) feedback for obtaining the approximate system throughput with JCS. Under the same number of feedback bits constraint, allocating the number of bits for channel direction information (CDI) and PI quantization can increase the system throughput, but ICS is still inferior to JCS. Based on theoretical analysis and simulation results, some recommendations are given with regard to the application of each scheme respectively.

• Journal of the Korea institute for structural maintenance and inspection
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• v.8 no.3
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• pp.159-167
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• 2004

The objective of this study is development of the optimum design program to minimize the cost for PSC box girder bridge using the full staging method to indicate the necessity for the optimum design applied many types of bridges. It also considered the proper span length to girder depth ratio and the cell number along the width of bridge. This program used SUMT procedure and Kavlie's extended penalty function to allow infeasible design points in the process. Powell's direct method was used in searching design points and Gradient Approximate Method was used to reduce design hours. This study showed the convergence in design parameter and correlation of totally optimized cost according to cell numbers, span lengths, and lane numbers.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.135-149
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• 2002

To date, research on the regulation of melanogenesis has focused on factors which affect tyrosinase, the rate-limiting enzyme in the melanogenic pathway, by searching for chemicals which competitively inhibit tyrosinase function. Many types of tyrosinase inhibitors have been developed, but no satisfactory results have been made clinically until now, To find a new whitening agent, which effectively inhibits melanogenesis, we synthesized several compounds and selected compounds by cell-based assay system. Finally, 3, 4, 5-trimethoxy cinnamaie thymol ester(TCTE, Melasolv) was selected and the effects of TCTE on melanogenesis were investigated. Treatment of mouse-derived melanocyte melan-a cells with TCTE results in a marked down-regulation of tyrosinase activity. 80% decrease of tyrosinase activity occurs with 30uM TCTE treatment for 72 hours without affecting cell growth. The inhibition of tyrosinase activity is dose-dependent and melanin content was also decreased to 40%. From the in vitro tyrosinase assay using cell extract, TCTE does not act as a direct inhibitor of the enzyme. Treatment of melan-a cultures with TCTE blocks the increase in tyrosinase activity by either forskolin, 3-isobutyl-1-methtyl-xanthine. TCTE decreased the expression of tyrosinase, TRP-1 without effects on TRP-2 protein expression through the down regulation of tyrosinase and TRP-1 mRNA. From the results of cAMP immunoassays, intracellular levels of the cyclin nucleotide are unaffected in cells treated with TCTE. The inhibitory effects of melanin synthesis were also shown in reconstitute human epidermis model by topical application. These findings suggest that TCTE can be used for studying the regulation of melanogenesis and depigmenting agent.

• The Journal of Korean Obstetrics and Gynecology
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• v.28 no.1
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• pp.113-127
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• 2015

Objectives: This study was performed to analyze the trend of acne-related experimental studies in Korean medicine. Methods: We searched 17 articles related with experimental study of acne, published Korean medical journals from 2005 to 2014. We classified all articles according to the journal and checked on the kind of herbs. All articles were categorized into two types: cell experimental study and animal experimental study. Results: 1. Total 17 papers were searched; 7 articles (41.2%) were published in the Journal of Korean Medical Ophthalmology, Otolaryngology, Dermatology, 4 articles (23.5%) were published in the Journal of Korean Institute of Pharmacopuncture, 3 articles (17.6%) were published in Korean Journal of Oriental Physiology and Pathology, 2 articles (11.8%) were published in Korean Journal of Herbology, and 1 article (5.9%) was published in the Journal of Korean Medicine. 2. Total 17 kind of herbs were used in the studies; 10 articles (58.8%) used single herb, 7 articles (41.2%) used complex herbs. 3. Total 17 articles were categorized 2 types; 16 cell experimental studies (94.1%), 1 animal experimental study (5.9%). 4. Experimental researches were mainly investigated using Raw 264.7 cell line and P. acnes. The levels of NO, iNOS, $TNF-{\alpha}$, PGE, COX-2, $IL-1{\beta}$, IL-6, NF-kB were analyzed to confirm of herbs' antibacterial, anti-inflammatory, antioxidant activity. Conclusions: Searching for natural antibiotics, it is needed to do experimental studies continuously, and also needed to diversify the kind herbs and experimental bacteria.

• Parasites, Hosts and Diseases
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• v.58 no.3
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• pp.237-247
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• 2020

Dendritic cell is one of the first innate immune cell to encounter T. gondii after the parasite crosses the host intestinal epithelium. T. gondii requires intact DC as a carrier to infiltrate into host central nervous system (CNS) without being detected or eliminated by host defense system. The mechanism by which T. gondii avoids innate immune defense of host cell, especially in the dendritic cell is unknown. Therefore, we examined the role of host PI3K/AKT signaling pathway activation by T. gondii in dendritic cell. T. gondii infection or T. gondii excretory/secretory antigen (TgESA) treatment to the murine dendritic cell line DC2.4 induced AKT phosphorylation, and treatment of PI3K inhibitors effectively suppressed the T. gondii proliferation but had no effect on infection rate or invasion rate. Furthermore, it is found that T. gondii or TgESA can reduce H₂O₂-induced intracellular reactive oxygen species (ROS) as well as host endogenous ROS via PI3K/AKT pathway activation. While searching for the main source of the ROS, we found that NADPH oxidase 4 (NOX4) expression was controlled by T. gondii infection or TgESA treatment, which is in correlation with previous observation of the ROS reduction by identical treatments. These findings suggest that the manipulation of the host PI3K/AKT signaling pathway and NOX4 expression is an essential mechanism for the down-regulation of ROS, and therefore, for the survival and the proliferation of T. gondii.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.10a
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• pp.431-435
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• 2011

This paper presents optimized searching technique to improve the performance of H.264/AVC. The proposed CAVLC encoder uses forward and backward searching algorithm to compute the parameters. By zero-block skipping technique and pipelined scheduling, the proposed CAVLC encoder can obtain better performance. The experimental result shows that the proposed architecture needs only 66.6 cycles on average for each $16{\times}16$ macroblock encoding. The proposed architecture improves the performance by 13.8% than that of previous designs. The proposed CAVLC encoder was implemented using VerilogHDL and synthesized with Megnachip $0.18{\mu}m$ standard cell library. The synthesis result shows that the gate count is about 15.6K with 125Mhz clock frequency.

• KSBB Journal
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• v.24 no.3
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• pp.312-320
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• 2009

Stable cell preservation is an essential factor in the regenerative medicine for cell therapies and transplantation of biologic materials. In this study, we studied to provide more stable hypothermic preservation by protection of cell damage during the preservation at $4^{\circ}C$. The result of searching for key components that have excellent efficacy in hypothermic preservation of cells, we have identified the fact that the hypothermic preservation adding protein hydrolysates such as yeast hydrolysate is far superior to others. All protein hydrolysates that are derived from animal, plant and microbe sources have superior efficacy, especially the peptides which have molecular weights under 10 kDa have the best efficacy among the components of protein hydrolysate. The protein hydrolysates prevented the decrease of ATP level in the cells caused by hypothermic environment and they inhibited the generation of ROS. Adding antioxidants and control agents of osmotic pressure were showed to have more superior efficacy in hypothermic preservation. Finally, KUL261 solution (DMEM/F12 1 : 1 medium, yeastolate 1%, $\alpha$-tocopherol $100{\mu}M$, dextran 2.5%), the preservation solution developed in this study, showed the best efficacy in both cell viability and cell growth more than other conventional preservation solutions. In conclusion, the improved hypothermic preservation solution that contains the protein hydrolysates as a key component provide the best preservation efficacy. It provides better efficacy than other preservation solutions and will contribute to both the development of regenerative medicine and global commercialization in this therapeutic field.