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The existing studies lack research on the ductility of steel-reinforced high-strength concrete (SRHC) columns and current specifications restricted the use of high-strength concrete in steel-reinforced concrete (SRC) columns. To compensate for the shortcomings of the existing research and promote the application of high-strength concrete in SRC structures, we test six SRHC columns and one SRC column to examine the effects of the steel content, eccentric distance, and slenderness ratio on the ductility, bearing capacity, and failure mode of SRHC columns. Further, Abaqus finite element models are established to predict the influences of more parameters on post-peak ductility and analyze the relationship between strain development of the concrete and the decrease in bearing capacity of SRHC columns. The results show that the penetration of cracks into aggregate during failure is the primary reason for the poor ductility of the SRHC columns. Improving the confinement effect of the stirrups on concrete is the most effective measure to enhance the ductility of the SRHC columns. The decline in the stirrup spacing from 100 mm to 50 mm increased the ductility coefficient from 1.47 to 5.56. The effect of the steel content, stirrup strength, and slenderness ratio on the ductility coefficient of SRHC columns is less than 30%. After analyzing the reason for the error of current specifications, a modified formula with an error of less than 5% is developed.

This paper investigates the eccentric compression performance of high-strength steel reinforced concrete (SRC) columns. In addition, the feasibility of the calculation codes used for the load-carrying capacity of these columns is verified by eccentric compression tests on 10 high-strength SRC columns with Q460 and Q690 steels and two normal SRC columns with Q235 steel. Moreover, the influence of the steel strength, relative eccentricity, steel ratio, and stirrup spacing on the bearing capacity and ductility of the specimens is analyzed. It was found that the bearing capacity and ductility of the specimens significantly increases when the steel strength increases from 276.5 MPa to 774.2 MPa; the bearing capacity of the Q690 SRC column is slightly higher than that of the Q460 SRC column. In addition, the ductility coefficient of the Q690 SRC columns is significantly higher than that of the Q460 SRC columns. It was also found that increasing the eccentricity and steel ratio can improve the ductility of the specimens and the smaller stirrup spacing can enlarge the contribution of Q690 steel under the ultimate bearing capacity. It is demonstrated that Eurocode 4-2004 and AISC360-16 codes significantly underestimate the test results. In contrast, JGJ138-2016 slightly underestimates the test results when the relative eccentricity is 0.2 but overestimates the test results when the relative eccentricity is 0.6. Furthermore, in order to maximize the contribution of Q690 steel under ultimate bearing capacity, the expanded parameter analysis is carried out using a finite element model. Following the analysis results, the suggestions for designing high-strength SRC columns under eccentric load are provided.

Lung cancer is a common type of cancer with a high mortality rate in China. Cisplatin (Cis) is one of the most effective broad‑spectrum chemotherapeutic drugs for the treatment of advanced lung cancer. However, Cis resistance remains an obstacle in the treatment of advanced lung cancer. Pristimerin (Pris), a naturally occurring triterpenoid quinone compound, not only possesses anticancer properties, but also enhances chemosensitivity. Therefore, the present study aimed to investigate whether Pris can enhance the chemosensitivity of lung cancer cells to Cis and identify the underlying mechanism. A Cell Counting kit‑8 and flow cytometry were used to determine cell viability, cell cycle progression and apoptosis in A549 and NCI‑H446 cells. Western blotting was used to determine cell apoptosis‑related, cell cycle‑related and autophagy‑related proteins. The results showed that Pris inhibited cell proliferation, and induced G0/G1 arrest and cell apoptosis in A549 and NCI‑H446 cells. The western blotting revealed that Pris effectively synergized with Cis to induce cell apoptosis by inhibiting the microRNA‑23a/Akt/glycogen synthase kinase 3β signaling pathway and suppressing autophagy. In vivo xenograft experiments confirmed that Pris effectively synergized with Cis to suppress tumor growth. Collectively, these results indicate that Pris synergized with Cis and that this may be a potential therapeutic strategy to overcome lung cancer.

Wenze Sun,1 Ting Ai,2 Ying Gao,1 Yingbing Zhang,1 Jie Cui,1 Liping Song1 1Department of Radiation Oncology, 2Department of Neonatology, First Affiliated Hospital, Medical College of Xi'an Jiaotong University, Xi'an, People's Republic of China Background: MET is involved in the progression of several types of human cancers, while phospho-BAD(Ser-136) is a key molecule in apoptosis and might be regulated by MET. The aim of this study was to investigate the correlation between altered expression of MET and phospho-BAD in non-small cell lung cancer (NSCLC) and their association with clinicopathologic parameters and overall survival. Methods: MET and phospho-BAD(Ser-136) proteins were evaluated by immunohistochemical analysis in 183 paraffin-embedded specimens and were also assessed by Western blotting analysis in 12 frozen tumor tissue samples, which were representative examples of immunohistochemical staining. Results: Positive expression of MET and phospho-BAD(Ser-136) occurred in 67.2% and 49.2% of the 183 cases of NSCLC, respectively. However, neither MET expression nor phospho-BAD(Ser-136) expression was associated with any clinicopathologic parameter. A significant correlation was found between MET and phospho-BAD(Ser-136) expression levels evaluated by immunohistochemistry (r = 0.268, P < 0.001). Overexpression of MET was significantly associated with shortened overall survival in univariate analysis (P < 0.001). Moreover, patients with a MET+/phospho-BAD(Ser-136)+ phenotype had a poorer prognosis than others (P < 0.001). Multivariate Cox proportional hazard analysis confirmed that MET expression is a prognostic factor for NSCLC. Conclusion: MET expression might be correlated with phospho-BAD(Ser-136) expression, and may be an adverse predictor for NSCLC. Activation of the MET/phospho-BAD(Ser-136) signaling pathway might play a role in the development and progression of NSCLC. Keywords: MET, phospho-BAD, prognosis, non-small cell lung cancer

To determine the influence of different registration scopes and methods on kilo-voltage cone beam CT (kVCBCT) image and CT image and to estimate the appropriate clinical target volume (CTV)-to-planned target volume (PTV) margin for central-type non-small cell lung cancer in image-guided radiation therapy (IGRT).Twenty-six patients with central-type non-small cell lung cancer (NSCLC) who received IGRT were enrolled in this study and totally 104 flames of kVCBCT scanning acquired before radiotherapy were analyzed. First, registrations were performed by gray plus manual match and were compared among different registration scopes of tumor and tumor plus vertebra. Then, the results of registration as well as time cost using tumor plus vertebra as registration scope were compared among different registration methods of gray plus manual match and bone plus manual match. At last, 200 registrations using tumor plus vertebra as the registration scope performed by bone plus manual match were recorded and the CTV-to-PTV margin was calculated.There was no significant difference in X, Y and Z translational and rotational movements between the registration scopes of tumor and tumor plus vertebra when gray plus manual match was used as the registration method (P0.05). The registration results of gray plus manual match and bone plus manual match were equal when tumor plus vertebra was used as the registration scope (P0.05), but the time cost of bone plus manual match [(1.9±0.3) min] was shorter than that of gray plus manual match [(3.1±0.2) min]. The CTV-to-PTV margins were 5.3, 4.9 and 5.7 mm in X, Y, and Z directions respectively.For central-type NSCLC, tumor and vertebra can be used as registration scope and the bone plus manual match is suggested in IGRT. To avoid errors, we suggest a CTV-to-PTV margin of 6 mm.

Lung cancer is the major cause of cancer deaths worldwide due to its late diagnosis and poor outcome. Understanding genomic medicine may widen our vision into the oncogenesis of lung cancer and may open the door to improvements in the clinical management of lung cancer. It is well known that almost half of all genes are regulated by microRNAs (miRNAs). This review focuses on the role of miRNAs in lung cancer and also touches on the value of miRNA-based novel therapies for lung cancers.