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The hot-dip galvanized coating was produced on the 7075 aluminum alloy plate by immersion in a pure zinc bath at different temperature from 440°C to 470°C for different modification time (between 1 min and 10 min). The hot-dip galvanized of the treated and un-treated samples were investigated by using scanning electron microscopy (SEM) with EDX analysis, X-ray diffraction (XRD), hardness measurements and potentiodynamic polarization curves. There were three layers fabricated on the 7075 substrate surface, specifically, zinc-rich layer, two-phase mixed layer Al-Zn and interdiffusion layer. Moreover, the 7075 aluminum alloy with the hot-dip galvanized coating exhibit higher hardness and better anti-corrosion properties in comparison with the 7075 substrate.

A composite surface layer was fabricated on a high-vanadium alloy steel (HVAS) plate by means of a surface gas nitriding at 550°C for 70h. The microstructural charaterization and phase analysis of resultant nitride layers were performed using optical, scanning electron microscopy, electron probe microanalyzer, X-ray diffraction methods and hardness measurements. The results of the investigation showed that a composite layer consisting of ε-Fe2–3N and γ'-Fe4N phases is feasible on the surface of HVAS. Vickers hardness test indicate that the hardness value of the nitrided sample is about 1100 HV at the top surface, and decreases gradually to about 700 HV in the matrix. The depth of hardened layer after surface gas nitriding was about 200 μm.

Radiation can activate the phosphatidylinositol 3-kinase/Akt pathway and cannot downregulate survivin expression in breast cancer cells. Deguelin induces apoptosis in breast cancer cells by inhibiting pAkt and survivin expression. In this study, we assessed the effect of deguelin on radiosensitization of human breast cancer cells and its possible mechanism.Deguelin and radiation were administrated in MDA-MB-231 human breast cancer cells. The cytotoxic interactions and mutual influences between these 2 modalities were analyzed by a series of assays including clonogenic, flow cytometric, and Western blotting.Phospho-Akt expression and survivin expression significantly decreased after 10 nM deguelin treatment, while phospho-Akt expression increased and survivin expression did not alter after radiation (3 Gy). However, phospho-Akt expression and survivin expression further significantly decreased after deguelin combined with radiation treatment. Deguelin combined with radiation markedly decreased clonogenic cell survival. After treatment of deguelin (10 nM) combined with radiation (3 Gy), caspase-dependent apoptosis was significantly increased and cell cycle was arrested in the G2-M phase in MDA-MB-231 cells.Deguelin attenuates radiation-induced prosurvival Akt signaling and enhances the radiosensitivity of MDA-MB-231 cells, and the mechanisms for this action may include inhibiting phospho-Akt and survivin expression, increasing caspase-dependent apoptosis, and prolonging cell cycle arrest in the G2-M phase.

Breast cancer stem cells (BrCSCs)have been first identified in solid tumors. To be more exact, they are defined as tumorigenic cancer cells which exhibit the capacity to form tumors distinct from the majority non-tumorigenic cancer cells. However it is only a minor subset that cancer stem cells are highly enriched in. It is still unknown how to find the definitive research subject - "a single breast cancer stem cell" - that can cause a new tumor by itself. Since recent studies suggest that BrCSCs have a higher proportion in suspension culture and have a greater resistance to chemotherapy regimens, we propose a novel strategy to isolate and identify BrCSCs:suspension culture combined with anticancer regimens. This double sorting method by means of the unique properties of BrCSCs may be helpful to screen genuine cancer stem cells(CSCs).

To investigate the minimal invasiveness of laparoscopic operation for colorectal carcinoma.Forty cases with pathologically proven colorectal carcinoma were divided into laparoscopic group (n=20) and open surgical group (n=20). Perioperative alterations of peripheral blood IL-6, IL-8, TNF-alpha, CRP, sICAM-1 and WBC CD11b were compared between the two groups. TNF-alpha, IL- 6, IL- 8 and sICAM-1 were determined by ELISA, CRP by scattered radiation turbidity comparison and WBC CD11b by flow cytometry with monoclonal antibody PS- CD11b, M2Ab.The postoperative cytokine levels of TNF-alpha, IL-6 and IL-8 in open surgery group were significantly higher than those in laparoscopic group (P0.05). Dynamic level of sICAM-1 at 6 and 24 hours after operation in open surgery group were significantly higher than those in laparoscopic group. Peripheral WBC CD11b decreased to the lowest level at 6 hours after operation in open surgery group,significantly lower than that in laparoscopic group (P0.05).Laparoscopic surgery for colorectal carcinoma exerts less effects on patients than traditional open surgery, and can maintain patients defense function,therefore it is less invasive.

Background Cancer stem cell (CSC) hypothesis has not been well demonstrated by the lack of the most convincing evidence concerning a single cell capable of giving rise to a tumor. The scarcity in quantity and improper approaches for isolation and purification of CSCs have become the major obstacles for great development in CSCs. Here we adopted suspension culture combined with anticancer regimens as a strategy for screening breast cancer stem cells (BrCSCs). BrCSCs could survive and be highly enriched in non-adherent suspension culture while chemotherapeutic agents could destroy most rapidly dividing cancer cells and spare relatively quiescent BrCSCs. Methods TM40D murine breast cancer cells were cultured in serum-free medium. The expression of CD44+CD24- was measured by flow cytometry. Cells of passage 10 were treated in combination with anticancer agents pacilitaxel and epirubicin at different peak plasma concentrations for 24 hours, and then maintained under suspension culture. The rate of apoptosis was examined by flow cytometry with Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) double staining method. Selected cells in different amounts were injected subcutaneously into BALB/C mice to observe tumor formation. Results Cells of passage 10 in suspension culture had the highest percentage of CD44+CD24- (about 77 percent). A single tumor cell in 0.35 PPC could generate tumors in 3 of 20 BALB/C mice. Conclusion Suspension culture combined with anticancer regimens provides an effective means of isolating, culturing and purifying BrCSCs.