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The mechanical properties of the static and dynamic compression of concrete eroded by a 15% sodium sulfate solution were explored with a 70-mm-diameter true triaxial static-dynamic comprehensive loading test system, and an analysis of the weakening mechanisms for the degree of macroscopic damage and microscopic surface changes of eroded concrete were conducted in combination with damage testing based on relevant acoustic characteristics and SEM scanning. The experience obtained in this paper is used to analyze and solve the problem that the bearing capacity of concrete buildings is weakened due to the decrease in durability under the special conditions of sulfate erosion. The results showed that, in a short time, the properties of concrete corroded by sulfate solution were improved to a certain extent due to continuous hydration. When the corrosion time was prolonged, the internal concrete structure was destroyed after it was eroded by sulfate, and its dynamic and static strength, deformability, and energy absorption were reduced to differing degrees, thus greatly inhibiting the overall mechanical performance of concrete, the dynamic compressive strength changed with strain that exhibited a significant strain rate effect, and, under the influence of sulfate erosion and hydration, the longitudinal wave velocity increased first and then decreased. The longitudinal wave velocity was slower than that of concrete under normal environment and distilled water immersion condition. SEM and acoustic wave analysis indicated that the internal concrete structure was destroyed after it was eroded by sulfate, and its dynamic and static strength, deformability, and energy absorption were reduced to differing degrees, thus greatly inhibiting the overall mechanical performance of concrete.

Lung cancer remains one of the most aggressive human malignancies with a low survival rate. Hyperoside (quercetin-3-O-β- d -galactopyranoside) is a flavonol glycoside with an anti-cancer activity. The microRNA-let-7 was widely regarded as a tumor suppressor in human tumors. Here, we investigated the role of hyperoside and let-7a-5p on the lung cancer cell proliferation, cell cycle and apoptosis in A549 cells in vitro. Our results showed that hyperoside could inhibit the proliferation of A549 cells through inducing apoptosis and G1/S phase arrest. Let-7a-5p could inhibit the proliferation of A549 cells via inhibiting the process of G1/S phase. Additionally, hyperoside and let-7a-5p had a synergetic effect on suppressing the proliferation of A549 cells; microRNA-let-7a-5p directly regulated the expression of CCND1 in A549 cells. Our study illustrated that hyperoside and microRNA-let7a-5p might provide a synergistic effect on anti-cancer, which may provide a new idea for lung cancer treatment.

Megakaryoblastic leukemia 1 (MKL1) was closely related to the pathogenesis of various human malignant cancers. MiR34a was reported to be closely related to cancer cell proliferation. Forkhead box protein 3 (FOXP3) was a transcription factor that played a different role in different cancer types. CDK6 was involved in cell cycle progression and was upregulated in several types of cancers. The present study investigated the effects of MKL1/miR34a/FOXP3 axis on cell proliferation in MGC803 gastric cancer cells. Our results demonstrated that overexpression of MKL1 promoted proliferation of MGC80-3 cells, MKL1 directly binding to the promoter of CDK6 to increase its expression. Knockdown of FOXP3 promoted proliferation of MGC80-3 cells and MKL1 inhibited the expression of FOXP3 via miR-34a. The finding can contribute to elucidating the regulatory mechanism involved in the cell cycle progression of gastric cancer cells and may aid in screening potential gene targets for the biological therapy of gastric cancer.

In order to predict the application effects of inorganic polymer-based fast-hardening concrete (IPFC) in pavement emergency repair, the slag, fly ash and silica fume were used as solid cementitious materials, and sodium hydroxide and sodium silicate were used as alkali-activators to prepare IPFC specimens. The change rules of the basic mechanical properties of the specimens with different slag, fly ash and silica fume contents in early stage were studied by experiments. The results show that, the early compressive strength of each group of specimens is more than 20 MPa and that of slag-based fast-hardening concrete (SFC) specimens is the highest. SFC specimens have the highest bending strength when they are cured for 2 h, while the silica fume/slag-based fast-hardening concrete (SSFC) specimens have the highest bending strength when the curing time is up to 3 h.

Signal transducer and activator of transcription 3 (Stat3) and Myocardin regulate cardiomyocyte differentiation, proliferation, and apoptosis. We report a novel aspect of the cellular function of Myocardin and Stat3 in the regulation of cardiomyocyte apoptosis. Myocardin and Stat3 showed anti-apoptotic function by increasing the expression of Bcl-2 while reducing expression of the pro-apoptotic genes Bax, Apaf-1, caspase-9, and caspase-3. Moreover, myocardin/Stat3-mediated activation of Bcl-2 and Mcl-1 transcription is contingent on the CArG box. Myocardin and Stat3 synergistically inhibited staurosporine-induced cardiomyocyte apoptosis by up-regulating expression of anti-apoptotic Bcl-2 and Mcl-1 in neonatal rat cardiomyocytes. These results describe a novel anti-apoptotic Myocardin/Stat3 signaling pathway operating during cardiomyocyte apoptosis. This provides a molecular explanation for cardiomyocyte apoptosis inhibition as a critical component of myocardial protection.

Epithelial-mesenchymal transition (EMT) plays an important role in breast cancer cell metastasis. Both (megakaryoblastic leukemia)/myocardin-like 1 (MKL-1) and Signal transducer and activator of transcription 3 (STAT3) have been implicated in the control of cellular metabolism, survival and growth. Our previous study has shown that cooperativity of MKL-1 and STAT3 promoted breast cancer cell migration. Herein, we demonstrate a requirement for MKL-1 and STAT3 in miRNA-mediated cellular EMT to affect breast cancer cell migration. Here we show that cooperativity of MKL-1 and STAT3 promoted the EMT of MCF-7 cells. Importantly, MKL-1 and STAT3 promoted the expression of Vimentin via its promoter CArG box. Interestingly, miR-93-5p inhibits the EMT of breast cancer cells through suppressing the expression of MKL-1 and STAT3 via targeted their 3’UTR. These results demonstrated a novel pathway through which miR-93-5p regulates MKL-1 and STAT3 to affect EMT controlling breast cancer cell migration.

Worldwide, hepatocellular carcinoma (HCC) remains a crucial medical problem. Precise and concise prognostic models are urgently needed because of the intricate gene variations among liver cancer cells. We conducted this study to identify a prognostic gene signature with biological significance. We applied two algorithms to generate differentially expressed genes (DEGs) between HCC and normal specimens in The Cancer Genome Atlas cohort (training set included) and performed enrichment analyses to expound on their biological significance. A protein-protein interactions network was established based on the STRING online tool. We then used Cytoscape to screen hub genes in crucial modules. A multigene signature was constructed by Cox regression analysis of hub genes to stratify the prognoses of HCC patients in the training set. The prognostic value of the multigene signature was externally validated in two other sets from Gene Expression Omnibus (GSE14520 and GSE76427), and its role in recurrence prediction was also investigated. A total of 2000 DEGs were obtained, including 1542 upregulated genes and 458 downregulated genes. Subsequently, we constructed a 14-gene signature on the basis of 56 hub genes, which was a good predictor of overall survival. The prognostic signature could be replicated in GSE14520 and GSE76427. Moreover, the 14-gene signature could be applied for recurrence prediction in the training set and GSE14520. In summary, the 14-gene signature extracted from hub genes was involved in some of the HCC-related signalling pathways; it not only served as a predictive signature for HCC outcome but could also be used to predict HCC recurrence.

Background Breast cancer is the leading cause of cancer death in women worldwide which is closely related to metastasis. But the exact molecular mechanism of ERα-36 and STAT3 on metastasis is still not fully understood. Methods MCF-7 and MDA-MB-231 human breast cancer cell lines and MCF-10A were overexpressioned or knockdown ERα-36 and STAT3 and tested for migration, invasion and proliferation assays. Direct interaction of STAT3 and ERα-36 were analyzed by coimmunoprecipitation assays. The effect of STAT3 and ERα-36 on MMP2/9 expression was analyzed by qPCR and western blotting. STAT3 phospholyation and acetylation by ERα-36 and p300 were observed and quantified by coimmunoprecipitation assays and western blotting. Results Cross-talk between ERα-36 and STAT3 was demonstrated to mediate through a direct physical association between the two proteins. Furthermore, the interaction between ERα-36 and STAT3 was demonstrated to give rise to functional changes in their signaling events. Both MMP2 and MMP9 expression require the binding of the newly identified protein complex, ERα-36-STAT3, to its promoter, the second phase, which is more robust, depends on ERα-mediated recruitment of p300 onto the complex and the subsequent acetylation of STAT3. In addition, STAT3 is tyrosine-phosphorylated in a biphasic manner, and the late phase requires ERα-36-mediated p300-dependent acetylation. Furthermore, interference with acetylation of STAT3 by overexpression of acetylation null STAT3 mutant led to the loss of MMP2 and MMP9 expression. ChIP analysis and reporter gene assays revealed that ERα-36-STAT3 complex binding to the MMP2 and MMP9 promoter led to an enhanceosome formation and facilitated MMP2 and MMP9 expression. Conclusions Our studies demonstrate for the first time that the function of MMP2 and MMP9 in breast cancer cell migration, which is mediated by interactions between ERα-36 and STAT3.

Signal transducer and activator of transcription 3 (STAT3) and Chemokine CX3C ligand 1 (Fractalkine/CX3CL1) play important roles in vascular inflammation and injury. To study if STAT3 promotes vascular endothelial cell proliferation and migration through fractalkine, we overexpressed or knocked down STAT3 in vascular endothelial cells, and used quantitative real-time PCR and Western blotting to determine the effect of STAT3 on fractalkine expression. The wild type and STAT3 binding site mutant fractalkine promoter luciferase reporter plasmids were constructed, and luciferase activity assays were used to explore the effect of STAT3 on the transcriptional activity of the fractalkine promoter. MTT assays were used to detect the effect of overexpression or knockdown of STAT3 or fractalkine on the proliferation rate of vascular endothelial cells. Scratch assays were used to detect the effect of overexpression or knockdown of STAT3 or fractalkine on vascular endothelial cell migration. There results showed that overexpression of STAT3 could promote fractalkine expression, and knockdown of STAT3 could down-regulate fractalkine expression. STAT3 could directly bind to the promoter of fractalkine to promote its transcriptional activity via binding the GAS site of the fractalkine promoter. Knockdown of STAT3 could inhibit the migration of vascular endothelial cell, and overexpression of fractalkine antagonized this inhibition. Our data concluded that STAT3 promotes the proliferation and migration of vascular endothelial cell by binding the GAS site of the fractalkine promoter to promote fractalkine transcriptional activity and expression.信号转导和转录活化因子3 (STAT3) 与趋化因子CX3C 配体1 (Fractalkine/CX3CL1) 在血管炎症和损伤中起重要作用，为了探讨STAT3 是否通过CX3CL1 促进血管内皮细胞增殖和迁移，在血管内皮细胞 (HUVEC)中过表达或敲降STAT3，通过quantitative real-time PCR、Western blotting 实验确定STAT3 对CX3CL1 表达的影响。构建含有STAT3 结合位点及突变STAT3 结合位点的CX3CL1 启动子荧光素酶报告基因质粒，利用荧光素酶活性分析实验研究STAT3 对CX3CL1 启动子转录活性的作用。利用MTT 实验检测过表达或敲降STAT3 或CX3CL1对血管内皮细胞增殖率的影响。利用划痕实验检测过表达或敲降STAT3 或CX3CL1 对血管内皮细胞迁移率的影响。结果显示，过表达STAT3 可以促进CX3CL1 表达，敲降STAT3 可以使CX3CL1 表达下调。STAT3 可以直接结合到CX3CL1 的启动子促进其转录激活，其促进作用依赖于CX3CL1 启动子上的GAS 位点。敲降STAT3 可以抑制血管内皮细胞的迁移，过表达CX3CL1 拮抗该抑制作用。总结得出，STAT3 通过结合到CXCL1 启动子促进CX3CL1 转录与表达进而促进血管内皮的增殖与迁移。.

Anti-ultraviolet Mg–Al hydrotalcite samples (MgAl–P-LDH) with 4-metoxybenzoic acid (PMOBA) ion intercalation were prepared by high temperature reduction method. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), UV–Visible absorption spectrophotometry, Fourier transform infrared spectroscopy (FTIR) and thermogravimetry. SEM images indicate that the UV-resistant MgAl–P-LDH had a layered structure. The results of X-ray diffraction analysis showed that the purity of MgAl–P-LDH sample was higher. Compared to MgAl-LDH, the characteristic peak for MgAl–P-LDH shifted towards small angle of 2θ, and it was found that the PMOBA ions have been inserted into the interlayer of MgAl hydrotalcite. The infrared spectra also showed that PMOBA ions were successfully intercalated within Mg–Al hydrotalcite layer. The ultraviolet absorption of MgAl–P-LDH was better than that of PMOBA and MgAl-LDH with the wavelength range of 225–325 nm, and the maximum absorption over 80% was observed.

Tumor cells metabolize more glucose to lactate in aerobic or hypoxic conditions than normal cells. Pyruvate kinase isoenzyme type M2 (PKM2) is crucial for tumor cell aerobic glycolysis. We established a role for let-7a-5p/Stat3/hnRNP-A1/PKM2 signaling in breast cancer cell glucose metabolism. PKM2 depletion via small interfering RNA (siRNA) inhibits cell proliferation and aerobic glycolysis in breast cancer cells. Signal transducer and activator of transcription 3 (Stat3) promotes upregulation of heterogeneous nuclear ribonucleoprotein (hnRNP)-A1 expression, hnRNP-A1 binding to pyruvate kinase isoenzyme (PKM) pre messenger RNA, and the subsequent formation of PKM2. This pathway is downregulated by the microRNA let-7a-5p, which functionally targets Stat3, whereas hnRNP-A1 blocks the biogenesis of let-7a-5p to counteract its ability to downregulate the Stat3/hnRNP-A1/PKM2 signaling pathway. The downregulation of Stat3/hnRNP-A1/PKM2 by let-7a-5p is verified using a breast cancer. These results suggest that let-7a-5p, Stat3, and hnRNP-A1 form a feedback loop, thereby regulating PKM2 expression to modulate glucose metabolism of breast cancer cells. These findings elucidate a new pathway mediating aerobic glycolysis in breast cancers and provide an attractive potential target for breast cancer therapeutic intervention.

Breast cancer is the leading cause of cancer death in women worldwide which is closely related to metastasis. Our previous study has shown that MRTF-A promote the migration of MDA-MB-231 cells and WDR1 promotes breast cancer cell migration. But the exact molecular mechanism on metastasis is still not fully understood, we now report that WDR1 enhanced the effect of MRTF-A induced-MDA-MB-231 cell migration by promoting the expression of the EMT markers and migration markers via RhoA-MRTF-A signaling pathway. Importantly, WDR1 promoted the nuclear importion of MRTF-A by affecting the expression of nuclear transport protein importin. But WDR1 did not affect the expression of MRTF-A. Interestingly, MRTF-A promoted the expression of miR-206 via its promoter CArG box but miR-206 inhibits the migration of breast cancer cells through suppressing the expression of WDR1 and MRTF-A via targeted their 3'UTR. Our data thus provide important and novel insights into MRTF-A-miR-206-WDR1 form feedback loop to regulate breast cancer cell migration.

CD44, cluster of differentiation 44 is a typical marker of stem cells. At present, it has been found that CD44 is prevalent in various human malignant tumors, but its expression regulation mechanism is still not clear. The initiation of gene expression, the modification of RNA levels, and the regulation of protein levels are the main factors affecting the expression level of genes, and the most critical one is the regulation of gene expression by signaling pathways. Up to now, there has been no report on the role of MKL-1 in the cloning of the cd44 promoter. Therefore, this study intends to clone the cd44 gene promoter, construct its luciferase reporter gene vector, transfect the MKL-1 overexpression vector, and analyze how it affects transcriptional activity, in order to further study the expression regulation of cd44. The mechanism provides a powerful tool in the future.