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Self-etching bonding systems are widely used in fiber post cementation. However, no clear guidelines are established for choosing pre- or co-curing procedures. We investigated the bond strength of fiber post cementation using pre-/co-curing methods in self-etching bonding systems and compared them with those of a self-adhesive system.Post spaces were prepared in 30 single-rooted premolars/canines, and the fiber posts were cemented in three ways (10 specimens per group): using a self-etching bonding system with either a pre-curing or simultaneous co-curing procedure (RelyX™ Ultimate; groups SE-pre and SE-co, respectively) and using a self-adhesive system (RelyX™ Unicem 2, group SA). Each specimen was embedded and sliced perpendicularly to the long axis into three 2.5-mm-thick sections. Microphotographs of the coronal and apical surfaces of each section were acquired, and push-out tests (1 mm/min) were performed. One-way analysis of variance was conducted on the data, followed by Tukey's honestly significant difference post hoc test.The bond strength in the whole root was not significantly different among the three groups. When independently evaluating each portion, group SE-co exhibited significantly lower coronal bond strength. The bond strength varied among root regions only in group SE-pre; the apical region had a significantly lower value.No cementation method is superior in all portions. Regarding pre-curing methods, clinicians must caution the fit between the post and post space, which may be affected by the pre-polymerized bond layer. The co-curing method used in a larger coronal cement space contributes to the poor bond strength.

Many power system application problems utilize optimal social welfare model as a decision-making tool. In this paper, we tackle the optimal social welfare problem based on a mathematic modeling framework capable to capture the interactions among decision-makers in an electric power supply chain network with consideration of transmission power flows and constraints which are neglected in previous literature, and present a generalized electric power supply chain network equilibrium model. In this model, each player tries to maximize its own profit and competes with others in a noncooperative manner. The Nash equilibrium conditions of these players form a finite-dimensional variational inequality problem (VIP). A modified penalty function (MPF) method is then used to replace conventional extragradient method for solving VIP by transforming VIP into a nonlinear programming problem. Numerical tests are conducted to demonstrate the effectiveness of the MPF for solving the VIP-based social welfare maximization model in the context of an electric power supply chain network.

Malignant cells are often resistant to complement activation through the enhanced expression of complement inhibitors. In this work, we examined the protective role of factor H, CD46, CD55, and CD59 in two non-small cell lung cancer cell lines, H1264 and A549, upon activation of the classical pathway of complement. Complement was activated with polyclonal Abs raised against each cell line. After blocking factor H activity with a neutralizing Ab, C3 deposition and C5a release were more efficient. Besides, a combined inhibition of factor H and CD59 significantly increased complement-mediated lysis. CD46 and CD55 did not show any effect in the control of complement activation. Factor H expression was knockdown on A549 cells using small interfering RNA. In vivo growth of factor H-deficient cells in athymic mice was significantly reduced. C3 immunocytochemistry on explanted xenografts showed an enhanced activation of complement in these cells. Besides, when mice were depleted of complement with cobra venom factor, growth was recovered, providing further evidence that complement was important in the reduction of in vivo growth. In conclusion, we show that expression of the complement inhibitor factor H by lung cancer cells can prevent complement activation and improve tumor development in vivo. This may have important consequences in the efficiency of complement-mediated immunotherapies.

Previously, we showed that magnolol induces cell-cycle arrest in cultured colon and liver cancer cells through an upregulation of the p21 protein. The aim of this study was to delineate the molecular mechanism underlying this magnolol-induced increase of p21 protein. Thus our RT-PCR analysis demonstrated that the mRNA levels of p21 were increased at 1 h after magnolol treatment and sustained for at least 24 h. The p21 promoter activity was also increased by magnolol treatment. Western blot analysis demonstrated that treatment of COLO-205 cells with magnolol increased the levels of phosphorylation of extracellular signal-regulated kinase (ERK). Pretreatment of the cells with PD98059 abolished the magnolol-induced upregulation of p21 protein, suggesting the involvement of an ERK pathway in the magnolol-induced upregulation of p21 in COLO-205 cells. Ras inhibitor peptide abolished the magnolol-induced increase of phosphorylated ERK protein levels, increase of p21 protein, and decrease of thymidine incorporation. Moreover, treatment of COLO-205 with magnolol increased the phosphorylated Raf-1 protein (the Ras target molecule). Pretreatment of the cells with Raf-1 inhibitor reversed the magnolol-induced decrease in thymidine incorporation. Treatment of the cells with CaM kinase inhibitor, but not protein kinase A (PKA) inhibitor or phosphatidylinosital 3-kinase (PI3K) inhibitor, abolished the magnolol-induced activation of ERK and decrease of thymidine incorporation. Taken together, our results suggest that magnolol activates ERK phosphorylation through a Ras/Raf-1-mediated pathway. Subsequently, p21 expression is increased, and finally thymidine incorporation is decreased.

The complement system is important for protection from invading pathogens, removal of waste products and guidance of the immune response. Furthermore, complement can be also targeted to cancer cells. However, membrane-bound inhibitors over-expressed by certain types of tumor cells restrict the cytotoxic activity of complement. Herein we report that non-small cell lung cancer (NSCLC) cells produce soluble complement inhibitors factor I (FI) and C4b-binding protein (C4BP). FI is a serine protease capable of degrading the activated complement components C3b and C4b, whilst C4BP acts as its cofactor. Furthermore, NSCLC cells express membrane-bound regulators and shed membrane cofactor protein (MCP), which shares cofactor function with C4BP. Secretion of FI from NSCLC cells was higher than previously reported for any non-hepatic source and FI produced by these cells could efficiently support cleavage of C3b and C4b. In vitro functional assays revealed that additional FI significantly decreased C3 deposition and complement-dependent lysis, particularly when cofactors were added. Our results demonstrate that soluble inhibitors produced by NSCLC cells may provide further protection from complement beyond the level ensured by membrane-bound inhibitors and, as such, contribute to the aggressive phenotype of these lung cancer cells.

The concept that lung adenocarcinoma is less related to smoking behavior than lung squamous cell carcinoma may be due to the fact that a considerable number of LAC patients do not have smoking habit. However, this argument may mislead the effect of tobacco smoke on LAC because it ignores the potential effects of environmental smoking that cause second hand smoking in non-smokers. In Taiwan, 70% of female LAC patients would encounter heavy smokers either at home or in working place, suggesting that environmental smoke may have substantial effects than we thought. Transcriptional deregulation at the chromosome 15q25 locus revealed an association between the gene encoding CHRNA5 with lung adenocarcinoma risk. It has been showed that overexpression of the genes encoded in this locus in mice increased the sensitivity to nicotine. In this report, we found that nAChR α5, but neither nAChR α7 or nAChR α9 that have been respectively shown to mediate tumorigenic alterations in lung SCC and breast cancer cells, was differentially expressed between tumor and non-tumor specimens of LAC patient specimens. Knockdown of nAChR α5 in LAC cell lines resulted in decreased cell proliferation rate as well as cell migrating and invasive capabilities. In these nAChR α5-knockdown cells, low dose (10 nM) nicotine was not able to significantly increase cell proliferation and motility, while low dose nicotine enhanced both abilities of cells when nAChR α5 expressed. Colony formation assay indicated that nAChR α5 maintained cell survival and prevent contact inhibition in LAC cells when encountering low serum stress condition. Through molecular analysis, we showed that nAChR α5 positively regulates epithelial-mesenchymal transition factors such as Snail and Slug, and negatively regulates E-cadherin. Animal experiment showed a severely suppressed tumor growth in mice transplanted with LAC cells with nAChR α5 being knocked down, in comparison to mice transplanted with parental cells. These data demonstrated a crucial role of nAChR α5 in low-dose nicotine-dependent regulation of tumorigenesis in LAC. It is, for the first time, a study of mechanism in response to low dose nicotine that implies the regulatory pathway underlying the effect of environmental nicotine. Citation Format: Mong-Lien Lotus Wang, Yi-Fan Hsu, Chih-Hsuan Liu, Cheng-Wen Wu. Nicotinic acetylcholine receptor α5 mediates low-dose nicotine-dependent regulation of tumorigenesis in lung adenocarcinoma cells. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4992. doi:10.1158/1538-7445.AM2015-4992

Macrophage proliferation and migration are important for many facets of immune response. Here we showed that stimulation of macrophages with type B CpG oligodeoxynucleotides (CpG-B ODNs) such as CpG-ODN 1668 increased the production of anti-inflammatory cytokine interleukin 1 receptor antagonist (IL-1Ra) in a TLR9- and MyD88-dependent manner. The CpG-B ODNs-induced IL-1Ra increased macrophage migration and promoted macrophage proliferation by down-regulating the expression of a cell cycle negative regulator, p27 to increase cell population in the S phase. The induction of IL-1Ra by CpG-B ODNs was F-spondin dependent. Knockdown of F-spondin and IL-1Ra decreased CpG-B ODNs-induced macrophage migration whereas overexpression of IL-1Ra increased migration of those cells. These findings demonstrated novel roles for F-spondin and IL-1Ra in CpG-B ODNs-mediated cell proliferation and migration of macrophages.