• Title/Summary/Keyword: Qingdao

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Role of P14 and MGMT Gene Methylation in Hepatocellular Carcinomas: a Meta-analysis

  • Li, Cheng-Cheng;Yu, Zhuang;Cui, Lian-Hua;Piao, Jin-Mei;Liu, Meng
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6591-6596
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    • 2014
  • Background: This meta-analysis was performed to investigate the relationship between methylation of the P14 and O6-methylguanine-DNA methyltransferase (MGMT) genes and the risk of hepatocellular carcinoma (HCC). Materials and Methods: We searched PubMed, EMBASE, the Chinese Biomedical Database (CBM), and the China National Knowledge Infrastructure (CNKI) databases to identify relevant studies that analysed HCC tissues for P14 and MGMT gene methylation status; we then performed a meta-analysis. Odds ratios (ORs) and 95% confidence intervals (95%CIs) were calculated to evaluate the association between gene methylation and the risk of HCC. Results: Ten studies that assessed P14 gene methylation in 630 HCC tumour tissues and nine studies analysing MGMT methylation in 497 HCC tumour tissues met our inclusion criteria. Our meta-analysis revealed that the rate of P14 methylation was significantly higher in HCCs than in adjacent tissues (OR 3.69, 95%CI 1.63-8.35, p=0.002), but there was no significant difference in MGMT methylation between HCC and adjacent tissues (OR 1.76, 95%CI 0.55-5.64, p=0.34). A subgroup analysis according to ethnicity revealed that P14 methylation was closely related to the risk of HCC in Chinese and Western individuals (Chinese, OR 7.74, 95%CI 1.36-44.04, p=0.021; Western, OR 3.60, 95%CI 1.49-8.69, p=0.004). Furthermore, MGMT methylation was not correlated with the risk of HCC in Chinese individuals (OR 2.42, 95%CI 0.76-7.73, p=0.134). The combined rate of P14 methylation was 35% (95%CI 24-48%) in HCC tumour tissues and 11% (95%CI 4-27%) in adjacent tissues, whereas the combined rate of MGMT methylation was 15% (95%CI 6-32%) in HCC and 10% (95%CI 4-22%) in adjacent tissues. Conclusions: These results suggest that the risk of HCC is related to P14 methylation, but not MGMT methylation. Therefore, P14 gene methylation may be a potential biomarker for the diagnosis of HCC.

Influence of Ionizing Radiation on Ovarian Carcinoma SKOV-3 Xenografts in Nude Mice under Hypoxic Conditions

  • Zhang, Yong-Chun;Jiang, Gang;Gao, Han;Liu, Hua-Min;Liang, Jun
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.5
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    • pp.2353-2358
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    • 2014
  • Purpose: We aimed to detect the expression of HIF-1${\alpha}$, VEGF, HPSE-1 and CD31 in SKOV3 xenografts in nude mice treated with different doses of ionizing radiation, trying to explore the possible mechanism of hypoxia and radioresistance. Methods: Nude mice bearing SKOV3 xenografts were randomly divided into 4 groups: Group A (control group, no ionizing radiation), Group B (treated with low dose of ionizing radiation: 50cGy), Group C (treated with high dose of ionizing radiation: 300cGy), Group D ( combined ionizing radiation, treated with ionizing radiation from low dose to high dose : 50cGy first and 300cGy after 6h interval). The mRNA levels of HIF-1 and VEGF in each group were detected by real time polymerase chain reaction, while HPSE-1 expression was measured by ELISA. The microvessel density (MVD) and hypoxic cells were determined through immunohistochemical (IHC) staining of CD31 and HIF-1a. Results: Significant differences of HIF-1${\alpha}$ mRNA level could be found among the 4 groups (F=74.164, P<0.001): Group C>Group A>Group D> Group B. The mRNA level of VEGF in Group C was significantly higher than in the other three groups (t=-5.267, P=0.000), while no significant difference was observed among Group A, B and D (t=1.528, 1.588; P=0.205, 0.222). In addition, the MVD was shown to be the highest in Group C (t=6.253, P=0.000), whereas the HPSE-1 level in Group A was lower than in Group B (t=14.066, P=0.000) and higher than in Group C (t=-21.919, P=0.000), and similar with Group D (t=-2.066, P=0.058). Through IHC staining of HIF-1a, the expression of hypoxic cells in Group A was (++), Group B was (+), Group C was (+++) and Group D was (+). Conclusion: Ionizing radiation with lowerdoses might improve tumor hypoxia through inhibiting the expression of HIF-1 and HPSE-1, whereas higherdoses worsen tumor hypoxic conditions by up-regulating HIF-1${\alpha}$, HPSE-1, VEGF and CD31 levels. A protocol of low-dose ionizing radiation followed by a high-dose irradiation might at least partly improve tumor hypoxia and enhance radiosensitivity.

APPROXIMATE SOLUTIONS TO ONE-DIMENSIONAL BACKWARD HEAT CONDUCTION PROBLEM USING LEAST SQUARES SUPPORT VECTOR MACHINES

  • Wu, Ziku;Li, Fule;Kwak, Do Young
    • Journal of the Chungcheong Mathematical Society
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    • v.29 no.4
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    • pp.631-642
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    • 2016
  • This article deals with one-dimension backward heat conduction problem (BHCP). A new approach based on least squares support vector machines (LS-SVM) is proposed for obtaining their approximate solutions. The approximate solution is presented in closed form by means of LS-SVM, whose parameters are adjusted to minimize an appropriate error function. The approximate solution consists of two parts. The first part is a known function that satisfies initial and boundary conditions. The other is a product of two terms. One term is known function which has zero boundary and initial conditions, another term is unknown which is related to kernel functions. This method has been successfully tested on practical examples and has yielded higher accuracy and stable solutions.

A Study on Competitive Power Comparison and Strategy Collaboration of the Biggest Three Ports of the Economic Circle Around Bohai

  • Meng, Qing-Chun;Sun, Han-Gao
    • Proceedings of the Korea Port Economic Association Conference
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    • 2007.07a
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    • pp.441-455
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    • 2007
  • Based on the fact that Qingdao port, Tianjin port and Dalian port of the economic circle around Bohai have been the three islands of stability through long-term competition, this paper conducts a system study on the competitive powers of the three ports through AHP model on the analysis of current status of the three ports, and probes deeply into the outer factors and the inner factors affecting on the competitive advantage, and points out the existing problems in competition. We think that the three ports must compete orderly and collaborate closely, and give the forms and approaches developing strategy collaboration in order to obtain an advantageous position in Northeast Asia and improve the international competitive power.

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Emerging Roles of Krüppel-Like Factor 4 in Cancer and Cancer Stem Cells

  • Ding, Bo;Liu, Ping;Liu, Wen;Sun, Ping;Wang, Chun-Ling
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.9
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    • pp.3629-3633
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    • 2015
  • Cancer stem cells (CSCs) are rare subpopulations within tumors which are recognized as culprits in cancer recurrence, drug resistance and metastasis. However, the molecular mechanisms of how CSCs are regulated remain elusive. Kr$\ddot{u}$ppel-like factors (KLFs) are evolutionarily conserved zinc finger-containing transcription factors with diverse functions in cell differentiation, proliferation, embryogenesis and pluripotency. Recent progress has highlighted the significance of KLFs, especially KLF4, in cancer and CSCs. Therefore, for better therapeutics of cancer disease, it is crucial to develop a deeper understanding of the mechanisms of how KLF4 regulate CSC functions. Herein we summarized the current understanding of the transcriptional regulation of K LF4 in CSCs, and discussed the functional implications of targeting CSCs for potential cancer therapeutics.

ABEP Performance of ISDF Relaying M2M Cooperative Networks

  • Xu, Lingwei;Wang, Jingjing;Wang, Han;Gulliver, T. Aaron
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.12
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    • pp.5129-5148
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    • 2016
  • In this paper, the average bit error probability (ABEP) performance of the incremental-selective decode-and-forward (ISDF) relaying mobile-to-mobile (M2M) cooperative networks over N-Nakagami fading channels is investigated. The exact ABEP expressions are derived, and the power allocation problem is formulated.The derived ABEP expressions are verified by Monte Carlo simulations. The simulation results showed that the propagation parameters, such as the fading coefficient, and the power-allocation parameter, have a significant influence on the ABEP performance.

Synthesis and Structure Analysis of α and β Forms of [12] Metallacrown-6 Nickel(II) Complex: [Ni6(SCH2CH2CH3)12]

  • Xiao, Hai Lian;Jian, Fang Fang;Zhang, Ke Jie
    • Bulletin of the Korean Chemical Society
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    • v.30 no.4
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    • pp.846-848
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    • 2009
  • Two modifications of the ${\alpha}\;and\;{\beta}$ forms of propyl mercaptan nickel(II) cluster, [$Ni_6(SCH_2CH_2CH_3)_{12}$], have been synthesized and their crystal structures have been determined by single-crystal X-ray diffraction. The alkyl groups are away from $Ni_6$ ring in $\alpha$ form whereas they are near to the Ni atom in $\beta$ form. The distance of Ni-H in $\beta$ form [2.576(5) $\AA$] is much shorter than that in $\alpha$ form [3.101(2) $\AA$]. In the crystal lattice of $\beta$ form, the whole structure forms a flower shape.