Objective To explore the microRNA-16 (miR-16) and nuclear-transcription factor-κB1 (NF-κB1) expressions in human brain gliomas and their correlations with cell invasion and growth of malignant gliomas SHG44,U87 and U373.Methods (1) Twenty-nine cases of human glioma tissue samples and 6 normal brain tissues,collected in our hospital from January 2000 to January 2011,were chosen in our study; quantitative real-time polymerase chain reaction (qRT-PCR) was used to determine the expressions ofmiR-16 and NF-κB1 in these tissues.(2) In vitro cultured U87,U373 and SHG44 cells were divided into blank-control group,nonsense sequence transfected group and miR-16 mimics transfected group; 48 h after the transfection,qRT-PCR was used to detect the expressions of miR-16 and NF-κB1; tmnswell assay was used to observe the cell invasion capability; 72 h after the transfection,Western blotting was employed to detect the protein expressions of NF-κB1,matrix metallopeptidase 9 (MMP-9) and MMP-2.(3) Luciferase reporter assay was used to detect the target regulating role of miR-16 in NF-κB1 gene.(4) U87 cells were used as negative control group,and U87 cells carried stably expressed miR-16 gene were implanted into intracranial and subcutaneous nude mice (U87-miR-16 group); immunofluorescence was used to detect the MMP-9 expression,and immunohistochemical staining was used to detect the protein expressions of Ki-67,NF-κ B1 and MMP-9; subcutaneous tumor volume was measured and the growth curve was drawn.Results (1) The qPCR results showed that the expression of miR-16 in human brain glioma tissues was significantly lower than that in normal brain tissues; and gradually decreased miR-16 expressions were noted in gliomas of graded Ⅰ,Ⅱ,Ⅲ and Ⅳ (P＜0.05); NF-κB1 expression in human brain glioma tissues was significantly higher than that in normal brain tissues; and gradually increased NF-κB1 expressions were noted in gliomas of graded Ⅰ,Ⅱ,Ⅲ and Ⅳ (P＜0.05).(2) As compared with those in the blank-control group and nonsense sequence transfected group,miR-16 mimics transfected group had significantly increased miR-16 expression,decreased NF-κB1 mRNA expression,decreased invasiveness,and decreased protein expressions of NF-κB1 and MMP-9 (P＜0.05).(3) Luciferase reporter assay showed that the fluorescence normalized ratio in the pMIR-NF-κB1 group was signfcaintly higher than that in the pMIR-NF-κB1+pre-miR-16 group (P＜0.05).(4) As compared with the negative control group,the U87-miR-16 group on the 24-42 d of implantation had significantly smaller volume of tumors (P＜0.05),and lower MMP9 expression,and NF-κB1,MMP-9 and Ki-67 expressions (the proliferation index of Ki-67:13.91％ and 32.98％).Conclusion MiR-16 inhibits glioma cell invasion and growth through down-mgulating NF-κB1 and MMP-9 expressions.

Objective Tostudy the influence of pipe structures on the mixing uniformity of airborne effluents from nuclear power plant chimneys. Methods We used the computational fluid dynamics (CFD) method to simulate the velocity distribution and gas mixing in long straight pipes (I type) with square section and circular section, 90° single-bend pipes (L type) with square section and circular section, and 90° double-bend pipes (S type and U type) with square section and circular section. Results For the long straight pipe, due to the lack of flow disturbance caused by structural changes, the mixing effect was not good; when the pipe section was circular, it might take mixing distance 20 times the hydraulic diameter to achieve the uniformity index required by the relevant standard; for the square pipe, the distance might be longer. In the single bend pipe with square section, the velocity uniformity was improved more greatly after the bend, and the tracer gas met the mixing uniformity at a shorter distance (11 times the hydraulic diameter), as compared with the single bend pipe with circular section. For the S-type double-bend pipe, the tracer gas appeared uniformly mixed after a distance 6 times the hydraulic diameter in the square pipe, and 7 times the hydraulic diameter in the circular pipe. For the U-type double-bend pipe, the gas in the square pipe also achieved uniform mixing ata shorter distance downstream, and the airflow showed greater disturbance when passing through the bend. Conclusion The CFD method can make an accurate prediction for the change patterns of gas mixing uniformity in pipes with different structures, and can partially replace physical experiments to study the factors affecting the mixing uniformity of airborne effluents from the chimney of nuclear power plants.

Stage T1 lung cancer refers to the tumor with maximum diameter≤3 cm, surrounded by the pleural membrane of the lung or viscera, and does not exceed the lobar bronchus under the bronchoscope. The prognosis is generally good, but some of them are more invasive, and more aggressive treatments are needed to achieve the best prognosis. This article reviews which T1 lung cancers are susceptible to metastasis and their risk factors. It is hoped that such patients will receive the attention of relevant scholars, and when they are encountered clinically, a more aggressive approach will be taken to extend their life expectancy．