• Title/Summary/Keyword: 4-META

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Cloning of pcb Genes in Pseudomonas sp.P20 Specifying Degradation of 4-Clorobiphenyl (4-Chlorobiphenyl을 분해하는 Pseudomonas sp. P20의 pcb 유전자군의 클로닝)

  • 남정현;김치경
    • Microbiology and Biotechnology Letters
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    • v.22 no.4
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    • pp.353-359
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    • 1994
  • Pseudomonas sp. P20 was a bacterial isolate which has the ability to degrade 4-chlorobi- phenyl(4CB) to 4-chlorobenzoic acid via the process of meta-cleavage. The recombinant plasmid pCK1 was constructed by insetting the 14-kb EcoRI fragment of the chromosomal DNA containing the 4CB-degrading genes into the vector pBluescript SK(+). Subsequently, E. coli XL1-Blue was transformed with the hybrid plasmid producing the recombinant E. coli CK1. The recombinant cells degraded 4CB and 2,3-dihydroxybiphenyl(2,3-DHBP) by the pcbAB and pcbCD gene products, respectively. The pcbC gene was expressed most abundantly at the late exponential phase in E. coli CK1 as well as in Pseudomonas sp. P20, and the level of the pcbC gene product, 2,3-DHBP dioxygenase, expressed in E. coli CK1 was about two-times higher than in Pseudomonas sp. P20. The activities of 2,3-DHBP dioxygenase on catechol and 3-methylcatechol were about 26 to 31% of its activity on 2,3-DHBP, but the enzyme did not reveal any activities on 4-methylcatechol and 4-chlorocatechol.

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Interaction of ct-DNA with 2,4-Dihydroxy Salophen

  • Azani, Mohammad-Reza;Hassanpour, Azin;Bordbar, Abdol-Khalegh;Mirkhani, Valiollah
    • Bulletin of the Korean Chemical Society
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    • v.30 no.9
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    • pp.1973-1977
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    • 2009
  • In the present study, at first, 2,4-Dihydroxy Salophen (2,4-DHS), has been synthesized by combination of 1, 2-diaminobenzene and 2,4-dihydroxybenzaldehyde in a solvent system. This ligand containing meta-quinone functional groups were characterized using UV-Vis and IR spectroscopies. Subsequently, the interaction between native calf thymus deoxyribonucleic acid (ct-DNA) and 2,4-DHS, was investigated in 10 mM Tris/HCl buffer solution, pH 7.2, using UV-visible absorption and fluorescence spectroscopies, thermal denaturation technique and viscosity measurements. From spectrophotometric titration experiments, the binding constant of 2,4-DHS with ct-DNA was found to be (1.1 ${\pm}\;0.2)\;{\times}\;10^4\;M^{-1}.$ The fluorescence study represents the quenching effect of 2,4-DHS on bound ethidium bromide to DNA. The quenching process obeys linear Stern-Volmer equation in extended range of 2,4-DHS concentration. Thermal denaturation experiments represent the increasing of melting temperature of DNA (about 3.5 ${^{\circ}C}$) due to binding of 2,4-DHS. These results are consistent with a binding mode dominated by interactions with the groove of ct-DNA.

Association Between XRCC1 Gene Polymorphisms and Risk of Glioma Development: A Meta-analysis

  • Sun, Jian-Ying;Zhang, Chun-Yang;Zhang, Zhen-Jun;Dong, Yan-Fang;Zhang, An-Long;Wang, Zhi-Wei;Mei, Xiao-Long
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.9
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    • pp.4783-4788
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    • 2012
  • Objective: Previous studies of the association between X-ray cross-complementing group 1 (XRCC1) gene polymorphisms and the gliomas risk have yielded conflicting results, and thus a meta-analysis was performed to provide a more accurate estimation. Methods: A computerized literature search of 5 electronic databases was conducted to identify the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 11 studies (3,810 cases and 6,079 controls), 7 studies (2,928 cases and 5,048 controls), and 4 studies (1,461 cases and 2,593 controls) were finally included in the analyses of the association between XRCC1 Arg399Gln, Arg194Trp, and Arg280His polymorphisms and glioma risk, respectively. The pooled results showed that GlnGln carriage was associated with moderately increased risk of gliomas in Asians (GlnGln vs. ArgArg, OR=1.490, 95%CI 1.031-2.153; GlnGln/ArgGln vs. ArgArg, OR=1.321, 95%CI 1.037-1.684), whereas a marginal association was revealed in Caucasians. For the Arg194Trp polymorphism, although a significant association was shown in the homozygous genotype comparisons (TrpTrp vs. ArgArg, OR = 2.209, 95%CI 1.398-2.945), no significant link was found on subgroup analysis stratified by ethnicity. With regard to the Arg280His polymorphism, no significant association was found in each comparison. No particular study was found to significantly influence the pooled results, and no potential publication bias was detected. Conclusions: This meta-analysis suggested that the XRCC1 Arg399Gln polymorphism is moderately associated with increased risk of gliomas in Asians, while Arg194Trp and Arg280His polymorphisms demonstrated no significant influence. Due to the limited studies and the potential confounders, further studies are needed to confirm these results.

Comparison of Gadobenate Dimeglumine and Gadopentetate Dimeglumine for Breast MRI Screening: a Meta-analysis

  • Yang, Xiao-Ping;Han, Yue-Dong;Ye, Jian-Jun;Chen, Gang;Luo, Ying;Ma, Hong-Xia;Yu, Xue-Wen;Niu, Juan-Qin;Ren, Fang-Yuan;Guo, You-Ming
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.5089-5095
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    • 2014
  • Background: As a common and essential contrast medium at present, gadobenate dimeglumine has shown better performance than some other agents when applied to Breast Magnetic Resonance Imaging Screening (Breast MRI Screening). Nevertheless, reports on the diagnostic performance of these two mediums (gadobenate dimeglumine and gadopentetate dimeglumine) are not completely consistent. Objective: To assess the diagnostic value of gadobenate dimeglumine and gadopentetate dimeglumine for Breast MRI Screening in patients suffering from breast cancer and to provide more convinced evidence to guide clinical practice in terms of appropriate contrast agents. Data Sources and Review Methods: Original articles in English and Chinese published before January 2013 were selected from available databases (The Cochrane Library, PUBMED, EMBASE, Chinese Biomedical Literature Database, Chinese Scientific Journals Full-text Database, Chinese Journal Full-text). The criteria for inclusion and exclusion were based on the standard for diagnosis tests. Meta-Disc software (Version 1.4) was used for data analysis. Then, the area under curve (AUC) of SROC and the spearman rank correlation of sensitivity against (1-specificity) were calculated. Results: Total of 17 researches involving 1934 patients were included. The pooled sensitivity of gadobenate dimeglumine and gadopentetate dimeglumine were 0.99 (0.97, 1.00) and 0.93 (0.88, 1.00) respectively. The pooled specificity for these two contrast agents were 0.924 (0.902, 0.943) and 0.838 (0.817, 0.858) respectively, and the AUC of SROC curve were 0.9781 and 0.9215 respectively. Conclusions: Gadobenate dimeglumine can be regarded as a more effective and feasible contrast medium for Breast MRI Screening. At least 5% differences in diagnostic performance are usually considered as clinically relevant.

Prognostic Value of PLCE1 Expression in Upper Gastrointestinal Cancer: a Systematic Review and Meta-analysis

  • Cui, Xiao-Bin;Peng, Hao;Li, Su;Li, Ting-Ting;Liu, Chun-Xia;Zhang, Shu-Mao;Jin, Ting-Ting;Hu, Jian-Ming;Jiang, Jin-Fang;Liang, Wei-Hua;Li, Na;Li, Li;Chen, Yun-Zhao;Li, Feng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.22
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    • pp.9661-9666
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    • 2014
  • Background: A number of studies have identified a shared susceptibility locus in phospholipase C epsilon 1 (PLCE1) for esophageal squamous cell carcinoma (ESCC) and gastric cardia adenocarcinomas (GCA). However, the results of PLCE1 expression in esophageal and gastric cancer remain inconsistent and controversial. Moreover, the effects on clinicopathological features remain undetermined. This study aimed to provide a precise quantification of the association between PLCE1 expression and the risk of ESCC and GCA through meta-analysis. Materials and Methods: Eligible studies were identified from PubMed, Wanfang Data, ISI Web of Science, and the Chinese National Knowledge Infrastructure databases. Using RevMan5.2 software, pooled odds ratios (ORs) with 95% confidence intervals (CIs) were employed to assess the association of PLCE1 expression with clinicopathological features relative to ESCC or GCA. Results: Seven articles were identified, including 761 esophageal and gastric cancer cases and 457 controls. Overall, we determined that PLCE1 expression was associated with tumor progression in both esophageal cancers (pooled OR=5.93; 95%CI=3.86 to 9.11) and gastric cancers (pooled OR=9.73; 95%CI=6.46 to 14.7). Moreover, invasion depth (pooled OR=3.62; 95%CI=2.30 to 5.70) and lymph node metastasis (pooled OR=4.21; 95%CI=2.69 to 6.59) were linked with PLCE1 expression in gastric cancer. However, no significant associations were determined between PLCE1 overexpression and the histologic grade, invasion depth, and lymph node metastasis in esophageal cancer. Conclusions: Our metaanalysis results indicated that upregulated PLCE1 is significantly associated with an increased risk of tumor progression in ESCC and GCA. Therefore, PLCE1 expression can be appropriately regarded as a promising biomarker for ESCC and GCA patients.

Classification of Non-Signature Multimedia Data Fragment File Types With Byte Averaging Gray-Scale (바이트 평균의 Gray-Scale화를 통한 Signature가 존재하지 않는 멀티미디어 데이터 조각 파일 타입 분류 연구)

  • Yoon, Hyun-ho;Kim, Jae-heon;Cho, Hyun-soo;Won, Jong-eun;Kim, Gyeon-woo;Cho, Jae-hyeon
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.30 no.2
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    • pp.189-196
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    • 2020
  • In general, fragmented files without signatures and file meta-information are difficult to recover. Multimedia files, in particular, are highly fragmented and have high entropy, making it almost impossible to recover with signature-based carving at present. To solve this problem, research on fragmented files is underway, but research on multimedia files is lacking. This paper is a study that classifies the types of fragmented multimedia files without signature and file meta-information. Extracts the characteristic values of each file type through the frequency differences of specific byte values according to the file type, and presents a method of designing the corresponding Gray-Scale table and classifying the file types of a total of four multimedia types, JPG, PNG, H.264 and WAV, using the CNN (Convolutional Natural Networks) model. It is expected that this paper will promote the study of classification of fragmented file types without signature and file meta-information, thereby increasing the possibility of recovery of various files.

Meta-analysis of the Efficacy of Infliximab in Patients with Moderate-Severe Ulcerative Colitis (중등도-중증 궤양성 대장염 환자에서 infliximab의 치료효과에 대한 메타분석)

  • Kim, Jong Yoon;Lee, Sukhyang;Rhew, Ki Yon
    • Korean Journal of Clinical Pharmacy
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    • v.22 no.3
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    • pp.251-259
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    • 2012
  • Ulcerative colitis (UC) is characterized by a life-long chronic course with remissions and exacerbations. Use of biological therapies may reduce or delay the surgical procedures in patients with UC. The aim of this study was to determine the impact of infliximab (IFX) use on the rate of remission, surgical interventions, and the effect on quality of life in patients with moderate to severe UC. Literature was searched for studies that investigated the efficacy of IFX on the rate of remission, colectomy and quality of life (QoL) between January 1990 and June 2012 at MEDLINE, January 1988 and June 2012 at EMbase and others. Eleven trials were included in the meta-analysis; divided into placebo controlled 8 trials and intravenous corticosteroid controlled group 3 trials. In comparison to placebo control groups, patients who received IFX had an odds ratio (OR) of 3.712 (95% CI: 2.714, 5.079) for the short-term clinical remission, and 3.053 (95% CI: 2.044, 4.559) for the rate of long-term remission. In colectomy rate and quality of life (QoL), odds ratio were 0.566(95% CI: 0.387, 0.827) and 0.658 (0.505, 0.811) respectively. Any adverse reactions including infections, infusion reaction, rash and arthralgia were equivalent in both groups. Compared with intravenous corticosteroid controlled group, patients who received IFX had lower remission rate with short-term odds ratio 0.227 (95% CI: 0.033, 1.556) and long-term odds ratio 1.054 (95% CI: 0.317, 3.502) respectively. However, statistical significance was not showed with both two analyses. The higher adverse drug reaction (ADR) rates were occurred in the corticosteroid controlled groups. 73.3% of patients treated corticosteroid reported Cushing-like syndrome with moon face. In conclusion, IFX does increase remission rate and decrease the rate of colectomy in patients with UC without elevating any adverse reactions significantly. IFX also improves QoL in moderate to severe UC patients. It would not exceed the efficacy of intravenous corticosteroid, whereas intravenous corticosteroid also reported high rate of adverse reactions.

Association between Pax8-PPARγ1 Rearrangement and Follicular Thyroid Cancer: a Meta-Analysis

  • Li, Hang-Yu;Xie, Zhi-Hao;Xu, Cong-Hui;Pu, Mei-Ling;Chen, Zi-Yan;Yu, Miao;Wang, Heng-Shu;Zhou, Chen-Ming;Pu, Chao-Yu;Liu, Wei
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.9
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    • pp.4247-4250
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    • 2016
  • Background: Pax8 and peroxisome proliferator-activated receptor gamma 1 gene (Pax8-$PPAR{\gamma}1$) are important factors in tumors. Several studies have suggested that follicular thyroid cancer may arise from Pax8- $PPAR{\gamma}1$ rearrangement. In order to have a better understanding of the association between Pax8-$PPAR{\gamma}1$ rearrangement and follicular thyroid cancer, we conducted the presenmt meta-analysis. Materials and Methods: The information was extracted from PubMed, EMBASE and Web of Science. Statistic analysis was performed with Stata12.0 software. Odds ratios (ORs) were calculated using a fixed-effects model. We also performed heterogeneity and publication bias analyses. Results: Nine studies including 198 follicular thyroid cancer patients and 268 controls were considered eligible. The frequency of Pax8-$PPAR{\gamma}1$ rearrangement was significantly higher in the follicular thyroid cancer group than in the control group, with a pooled OR of 6.63 (95%CI=3.50-12.7). In addition, through subgroup analysis, the OR between Pax8-$PPAR{\gamma}1$ rearrangement and follicular thyroid cancer was 6.04 (95%CI = 3.18-11.5) when using benign tumor tissues as controls. The OR for the method subgroup was 9.99 (95% CI =4.86-20.5) in the RT-PCR. Conclusions: The final results demonstrated that Pax8-$PPAR{\gamma}1$ rearrangement has significant association with follicular thyroid cancer.

Nitric Oxide Synthase 3 Gene Variants and Colorectal Cancer: a Meta-Analysis

  • Chen, Yang;Li, Jie;Guo, Yun;Guo, Xiao-Yun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.8
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    • pp.3811-3815
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    • 2014
  • Background: Colorectal cancer (CRC) is the worldwide disease which causes enormous losses every year. Recent studies suggested that environmental and gene factors might be the etiologies in increasing the risk of morbidity. Nitric oxide synthase 3 (NOS3) gene polymorphisms are said to be associated with CRC risk but the conclusion is still controversial. Materials and Methods: Pubmed and HuGENet databases up to December 2013 were used in this meta-analysis. Three different certain genotypic models were applied, namely dominant (AA+AC versus CC), recessive (AA versus AC+CC), per-allele analysis (A vs C). In addition, information on tumor sites and pathologic stages was collected. The strength of associations was assessed through combining odds ratio (OR) and 95% confidence interval (CI). Results: Finally, five and three studies about the rs1799983 and rs2070744 were covered in the analysis with 2,745 cases and 2,478 controls. Three models were applied, but no significant association was found for NOS3 G894T/rs1799983 (dominant: OR=0.999, 95%CI=0.797-1.253, $I^2$=63.8%; recessive: OR=0.924, 95%CI=0.589-1.450, $I^2$=59.3%; allele analysis: OR=0.979, 95%CI=0.788-1.216, $I^2$=74.9%) and T-786C/rs2070744 (dominant: OR=1.138, 95%CI=0.846-1.530, $I^2$=67.9%; recessive: OR=0.956, 95%CI=0.708-1.291, $I^2$=0.0%; allele analysis: OR=1.110, 95%CI=0.865-1.425, $I^2$=69.4%). The same results were also obtained for tumor sites and pathologic stage subgroups. After further analyzing the NOS3 gene, rs1799983 as the tag- and functional SNP was presented. Conclusions: On the basis of this meta-analysis and the characteristics of the NOS3 gene, we suggested rs1799983 might be a key locus associated with CRC risk. Further prospective studies were needed to make more comprehensive explanation of the associations.

Verification of the Correlation between Progression-free Survival and Overall Survival Considering Magnitudes of Survival Post-progression in the Treatment of Four Types of Cancer

  • Liu, Li-Ya;Yu, Hao;Bai, Jian-Ling;Zeng, Ping;Miao, Dan-Dan;Chen, Feng
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.3
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    • pp.1001-1006
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    • 2015
  • Background: With development and application of new and effective anti-cancer drugs, the median survival post-progression (SPP) is often prolonged, and the role of the median SPP on surrogacy performance should be considered. To evaluate the impact of the median SPP on the correlation between progression-free survival (PFS) and overall survival (OS), we performed simulations for treatment of four types of cancer, advanced gastric cancer (AGC), metastatic colorectal cancer (MCC), glioblastoma (GBM), and advanced non-small-cell lung cancer (ANSCLC). Materials and Methods: The effects of the median SPP on the statistical properties of OS and the correlation between PFS and OS were assessed. Further, comparisons were made between the surrogacy performance based on real data from meta-analyses and simulation results with similar scenarios. Results: The probability of a significant gain in OS and HR for OS was decreased by an increase of the SPP/OS ratio or by a decrease of observed treatment benefit for PFS. Similarly, for each of the four types of cancer, the correlation between PFS and OS was reduced as the median SPP increased from 2 to 12 months. Except for ANSCLC, for which the median SPP was equal to the true value, the simulated correlation between PFS and OS was consistent with the values derived from meta-analyses for the other three kinds of cancer. Further, for these three types of cancer, when the median SPP was controlled at a designated level (i.e., < 4 months for AGC, < 12 months for MCC, and <6 months for GBM), the correlation between PFS and OS was strong; and the power of OS reached 34.9% at the minimum. Conclusions: PFS is an acceptable surrogate endpoint for OS under the condition of controlling SPPs for AGC, MCC, and GBM at their limit levels; a similar conclusion cannot be made for ANSCLC.