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Objective: This study aims to analyze the effect of lyophilized recombinant human brain natriuretic peptide on the endothelial function of patients with acute myocardial infarction. Methods: One hundred and thirty-six patients with acute myocardial infarction in our hospital were randomly divided into a control group and an experimental group (68 cases each). The patients in the control group were treated by conventional treatment. The patients in the experimental group were treated with lyophilized recombinant human brain natriuretic peptide besides the conventional treatment. The levels of flow-mediated dilatation (FMD), serum nitric oxide (NO), and endothelin-1 were compared between the two groups before and after treatment. Results: Before treatment, there was no significant difference between the two groups in the level of FMD (P>0.05); after treatment, the level of FMD in the experimental group was higher than that in the control group, and the difference was statistically significant (P0.05); after treatment, the levels of serum NO and endothelin-1 in the experimental group significantly improved, which were better than those in the control group (P

Baicalein and baicalin are active components of the Scutellaria baicalensis Georgi and both have broad anti-tumor activity. However, how and whether baicalein and baicalin inhibit colon cancer is unclear. Here we demonstrate that baicalein and baicalin can significantly inhibit human colon cancer cell growth and proliferation. Furthermore, both can induce cell cycle arrest, and suppress cancer cell colony formation and migration. The suppressive effects are mechanistically due to the induction of colon cancer cell apoptosis and senescence mediated by baicalein and baicalin, respectively. Furthermore, we revealed that baicalin-induced senescence in tumor cells is due to its inhibition of telomerase reverse transcriptase expression in tumor cells, and that MAPK ERK and p38 signaling pathways are causatively involved in the regulation of colon cancer cell apoptosis and senescence mediated by baicalein and baicalin. In addition, our in vivo studies using human colon cancer cells in humanized mouse xenograft models, further demonstrated that baicalein and baicalin can induce tumor cell apoptosis and senescence, resulting in inhibition of tumorigenesis and growth of colon cancer in vivo. These data clearly suggest that baicalein and baicalin have potent anti-cancer effects against human colon cancer and could be potential novel and effective target drugs for cancer therapy.

Gas turbines normally have the rotating and stationary parts. The rotational blades always need clearance to rotation. Blade tip clearance is one of the important parameters affecting performance, safety and stability of a gas turbine engine. However, it is difficult to measure the tip clearance accurately during the tests. The numerical studies are important methods to study the tip clearance effects. Tip clearance effects have been studied for a long time. However, there are still many aspects that are not fully understood and industries still don’t have a good way to perform design with minimum tip clearance losses. In the gas turbine design, the tip clearance considerations are very critical for both performance and reliability. In this paper, we perform the numerical study on the tip clearance impacts during the aerodynamic design, especially the blade loading through blade counts. The study found that the proper blade loading could reduce the tip clearance sensitivity and reduce the tip clearance losses. In the cases of reasonable number of blades, the effect of clearance on the total pressure loss and efficiency had a linear relationship. But in the cases of small number of blades, the effect of clearance on the total pressure loss and efficiency is no longer linear. The study helped turbine designers to consider blade loading and tip clearance together during the turbine design.

Micro gas turbine is one of the ideal prime movers for small-distributed energy systems. It can effectively reduce the emission of greenhouse gases and nitrogen oxides. Moreover, the use of micro gas turbines will contribute to burning fossil fuels in a much cleaner way. The staged combustion technology is the favorite way for low pollution combustion chamber such like. Therefore, the influence of the proportion of pilot fuel in the combustion chamber on pollutant emission deserves further study. The object of this research is the Double annular swirler (Das), which was applied to a 100 kW micro gas turbine combustion chamber. The combustion performance and emission characteristics under different Pilot Fuel Ratios (PFR) were obtained in prototype experimental system. Under the experimental conditions, Computational fluid dynamics (CFD) method was applied to research the reacting flow field and the formation of NOx in the combustion chamber and then analyze the influences of PFRs on combustion process. Experimental results show that the NOx emission of Das decreased at first and then increased with the augment of PFR. When PFR was near to 11%, the per unit NOx emission concentration reached its minimum. The numerical simulation agreed well with the experimental data. Further analysis of the simulation results indicate that there is a strong correlation between Φlocal and NOx concentration. When it is lower than a certain value, the number of nitrogen oxides will be significantly reduced. The value has a lot to do with the inlet air temperature and the pressure of the combustion chamber under the design condition, and it needs to be confirmed by calculating the adiabatic temperature. Simultaneously, we also find that although the percentage of total air flowing into the combustor remains unchanged, the increase of PFR would reduce the airflow ratio in inner swirler. This implies that for some particular combustion chambers, special attention should be paid to the changes in air allocation caused by PFR.

Baicalin is a natural flavonoid glycoside which has potent anti-tumor and antioxidant activity in cancer cells. In the present study, we found that baicalin treatment significantly induced senescence in colon cancer cells. Furthermore, baicalin upregulated the expression of decidual protein induced by progesterone (DEPP) in HCT116 colon cancer cells, which accompanied with the activation of Ras/Raf/MEK/ERK and p16INK4A/Rb signaling pathways. Meanwhile, these phenomena also appeared under the anti-oxidation effect exerted by baicalin. In addition, ectopic expression of DEPP in HCT116 cells significantly induced the activity of senescence-associated β-galactosidase (SA-β-Gal) in tumor cells regulated by Ras/Raf/MEK/ERK signaling pathway. Knockdown of DEPP by RNA interference efficiently counteracted the baicalin-mediated growth inhibition, senescence and cell cycle arrest in cancer cells. Importantly, in a xenograft mouse model of human colon cancer, we further confirmed that baicalin treatment dramatically inhibited tumor growth, which was due to the induction of tumor cellular senescence via the upregulation of DEPP and the activation of Ras/Raf/MEK/ERK signaling in vivo. In addition to baicalin treatment, we found that the hypoxia-response protein DEPP functions as a positive regulator involving the regulations of Ras/Raf/MEK/ERK signaling pathway and inhibition of human colon cancer by other anti-oxidative drugs, such as curcumin and sulforaphane, resulting in tumor cellular senescence. These results collectively suggest that baicalin upregulates the expression of DEPP and activates its downstream Ras/Raf/MEK/ERK and p16INK4A/Rb pathways by acting as an antioxidant, leading to senescence in colon cancer cells.

An experimental investigation on the unsteady tip flow field of a transonic compressor rotor has been performed. The casing-mounted high frequency response pressure transducers were arranged along both the blade chord and the blade pitch. The chord-wise ones were used to indicate both the ensemble averaged and time varying flow structure of the tip region of the rotor at different operating points under 95% design speed and 60% design speed. The pitch-wise circumferential transducers were mainly used to analyze the unsteadiness frequency of the tip leakage flow in the rotor frame at the near stall condition. The contours of casing wall pressure show that there were two clear low pressure regions in blade passages, one along the chord direction, caused by the leakage flow and the other along the tangential direction, maybe caused by the forward swept leading edge. Both low pressure regions were originated from the leading edge and formed a scissor-like flow pattern. At 95% design speed condition, the shock wave interacted with the low pressure region and made the flow field unsteady. With the mass flow reduced, the two low pressure regions gradually contracted to the leading edge and then a spike disturbance emerged.

Zedoary turmeric oil (ZTO) is a volatile oil that is extracted from the dry rhizome of Curcuma zedoaria with a variety of biological activities, including anti-tumor activity. However, there is a lack of knowledge about the effect and mechanism of ZTO in human colon cancer cells. The aim of this study was to examine the potential efficacy of ZTO against human colon cancer cells (HCT116) and to uncover the molecular mechanisms of its anti-tumor effects. The anti-proliferative activity of ZTO was determined by the MTT assay, cell counts and colony formation assay. Senescent cells were detected using SA-β-Gal staining, while apoptosis and the CD44+ subpopulation were evaluated by flow cytometry. The expression levels of senescence- and apoptosis-related proteins were examined using western blotting. The results showed that treatment with ZTO significantly inhibited the growth of HCT116 cells and caused senescence and apoptosis in a dose- and time-dependent manner. Western blotting revealed that ZTO significantly increased the expression of senescence- and apoptosis-related proteins p16, p21, and p53 and the phosphorylation of ERK. Moreover, ZTO treatment reduced the cancer stem-like CD44 positive cell population. These findings suggest that ZTO inhibits human colon cancer cells by inducing senescence and apoptosis.