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The BiOI/TiO2 heterostructures with microsphere morphology were successfully synthesized via a solvent-thermal method. The photocatalytic performance of BiOI/TiO2 heterostructures was investigated via the degradation of Rhodamine B (RhB). The results indicate that the BiOI/TiO2 heterostructures exhibited excellent photocatalytic performance with a maximum RhB degradation rate of 91% after 2 h of visible light irradiation, and the RhB molecules were mainly degraded by the holes and superoxide radicals. The enhanced photocatalytic performance of the heterostructures was mainly ascribed to its large specific surface areas and the reduced recombination rate of the photo-generated electron-hole pairs, which caused by the introduction of TiO2. [ABSTRACT FROM AUTHOR]

Glioblastoma is one of the most frequent and aggressive brain tumors. Accumulating evidence indicates that microRNAs are involved in glioma proliferation, invasion and drug resistance. Previous studies showed that miR-198 is downregulated in glioblastoma. However, the function of miR-198 in glioblastoma is still unclear. In this study, we report that miR-198 levels were greatly downregulated in glioblastoma specimens and decreased expression of miR-198 was associated with poor prognosis in patients with glioblastoma. And overexpression of miR-198 increased chemosensitivity to temozolomide in vitro and in vivo. O-methylguanine-DNA methyltransferase (MGMT) was identified as a direct target of miR-198, and miR-198 overexpression prevented the protein translation of MGMT. Furthermore, overexpression of MGMT restored miR-198-induced chemosensitivity to temozolomide. Moreover, the protein levels of MGMT were upregulated in clinical glioblastoma specimens and inversely correlated with miR-198 levels. In conclusion, our studies revealed that MiR-198 induces chemosensitivity in glioblastoma by targeting MGMT and that miR-198 may be used as a new diagnostic marker and therapeutic target for glioblastoma in the future. [ABSTRACT FROM AUTHOR]

The present work investigates pollutant removal and the transformation of nitrogen from sewage wastewater using a pilot-scale multi-stage bio-vermifilter system. Over a study period of 48 weeks, the pollutant removal performance of the system was measured and the effects of hydraulic loading rate (HLR) and dry-wet ratio (D/W) were estimated. The relationship between oxygen transfer rate and load of oxygen necessity was calculated and analysed for system optimisation. The method for diluting the isotope δN-NO was applied to study nitrogen transfer. Moreover, statistical correlations were analysed to determine the crucial factors which influence nitrogen transfer efficiency. The system removes pollutants efficiently; specifically, the average removal efficiencies are 94.2 % for chemical oxygen demand (COD), 93.3 % for NH-N, and 58.2 % for total nitrogen (T-N). Lowering HLR and D/W can enhance nitrogen removal. Nitrogen speciation and transformation were examined under an optimised condition with an HLR of 0.36 m day and a D/W of 3. The results of isotope δN-NO dilution showed that NO-N was mainly produced in trickling bio-filter and vermibio-filter (VBF) I. By contrast, NO-N was mainly reduced in VBF II. Under stable operating conditions and environmental factors, COD/T-N was verified as the crucial factor in nitrogen removal. [ABSTRACT FROM AUTHOR]

Glioblastoma is the most common and fatal human brain malignancy in adults with highly proliferative capacity. Despite advances in surgery and adjuvant therapy, the median survival of patients has changed little over recent decades. Identifying molecules critical for glioma development is significant for devising effective targeted therapy. We previously reported that Bex2, a member of the brain expressed X-linked gene family, promoted the progression of glioma by promoting cell proliferation. In the present study, we investigated the main mechanism of Bex2 promoting the proliferation of glioblastoma cells. We found that Bex2 downregulation inhibited glioma cell proliferation and the expression of NF-κB p65, but Bex2 overexpression promoted them. Similarly, the proliferation of glioma cells was inhibited by p65 downregulation but increased by p65 overexpression. In addition, Bex2 overexpression-induced cell proliferation was abolished by p65 downregulation. Furthermore, Bex2 with nuclear localization signal deleted no longer promoted p65 expression. In conclusion, this study demonstrates that Bex2 promotes proliferation of human glioblastoma cells via NF-κB signaling pathway and Bex2 nuclear location is critical for p65 expression. [ABSTRACT FROM AUTHOR]

Purpose: The performances of filter systems that use earthworms and plants, combined with earthworm eco-filter (EE) systems in treating synthetic domestic sewage (SDS) with different C/N ratios, were investigated for a 9-month period. Methods: The effects of the combination of filters, earthworms, plants, as well as the combination of earthworms and plants on SDS nutrient removal efficiency were separately investigated to select the optimum system for treating SDS. The results of the current study could be used to determine how treatment performance responds to different C/N ratios and to explain and predict the performance of an operating EE system. Results: EE systems with earthworms and plants (EP groups) consistently performed better than the other types of systems (CK, E, and P; that is, without earthworms and without plants, with earthworms and without plants, and without earthworms and with plants, respectively) under all C/N ratios. The highest removal efficiencies of chemical oxygen demand, total nitrogen, total phosphorus, and total organic carbon were achieved under C/N ratios of 6:1, 6:1, 6:1, and 9:1, respectively. The optimum nutrient removal efficiency was achieved at C/N = 6, and the contribution order for nutrient removal was EP > P > E > CK. Conclusions: Influent C/N ratios, the time of year, and the synergetic effects of earthworm behavior and microorganisms significantly affected nutrient removal efficiencies. Considering the removal of all nutrients, EE systems with plants and earthworms achieved optimum removal effects in July when the influent C/N ratio was controlled at 6. Appropriate control of carbon and nitrogen source concentrations permitted the achievement of optimal nutrient removal effects. [ABSTRACT FROM AUTHOR]

Purpose: Two series of activated carbons modified by Fe (II) and Fe (III) (denoted as AC/N-Fe and AC/N-Fe), respectively, were used as adsorbents for the removal of phosphate in aqueous solutions. Method: The synthesized adsorbent materials were investigated by different experimental analysis means. The adsorption of phosphate on activated carbons has been studied in kinetic and equilibrium conditions taking into account the adsorbate concentration, temperature, and solution pH as major influential factors. Results: Maximum removals of phosphate are obtained in the pH range of 3.78-6.84 for both adsorbents. Langmuir isotherm adsorption equation well describes the experimental adsorption isotherms. Kinetic studies revealed that the adsorption process followed a pseudo-second order kinetic model. Results suggest that the main phase formed in AC/N-Fe and AC/N-Fe is goethite and akaganeite, respectively; the presence of iron oxides significantly affected the surface area and the pore structure of the activated carbon. Conclusions: Studies revealed that iron-doped activated carbons were effective in removing phosphate. AC/N-Fe has a higher phosphate removal capacity than AC/N-Fe, which could be attributed to its better intra-particle diffusion and higher binding energy. The activation energy for adsorption was calculated to be 22.23 and 10.89 kJ mol for AC/N-Fe and AC/N-Fe, respectively. The adsorption process was complex; both surface adsorption and intra-particle diffusion were simultaneously occurring during the process and contribute to the adsorption mechanism. [ABSTRACT FROM AUTHOR]

H19 expression is elevated in many human tumors including glioblastomas, suggesting an oncogenic role for the long noncoding RNA; yet the upregulation of H19 in glioblastomas remains unclear. Here we report that hypoxia significantly stimulated H19 expression in glioblastoma cell lines, which was related to hypoxia-inducible factors 1α (Hif-1α). Hif-1α promoted H19 expression in U87 and U251 cells. Meanwhile PTEN is an advantageous factor to affect H19 expression, through attenuating Hif-1α stability. Hif-1α also positively correlates with H19 in human glioblastoma samples depending on PTEN status. ChIP and luciferase reporter assays showed that Hif-1α induced H19 transcription through directly binding to the H19 promoter. Furthermore, Hif-1α upregulated specific protein 1 (SP1) expression in glioblastomas cells in vitro and in vivo, and SP1 also strongly interacted with the H19 promoter to promote H19 expression under hypoxia. We also showed that H19 acts as a molecular sponge that binds miR-181d, relieving inhibition of β-catenin expression. Therefore, H19 participates in hypoxia-driven migration and invasion in glioblastoma cells. In summary, our results uncover the mechanisms that stimulate H19 expression under hypoxia to promote malignant effects in glioblastomas and suggest H19 might be a promising therapeutic target. [ABSTRACT FROM AUTHOR]

The acquisition of drug resistance is a persistent clinical problem limiting the successful treatment of glioblastoma (GBM). However, the molecular mechanisms by which initially chemoresponsive tumors develop therapeutic resistance remain poorly understood. In this study, we report that BACH1, a heme-binding protein that participates in transcriptional repression or activation, was significantly upregulated in glioblastoma tissues. Overexpression of BACH1 in GBM cells conferred resistance to temozolomide, whereas its inhibition markedly sensitized resistant cells to temozolomide in vitro and in vivo. Further investigation revealed that BACH1 activation significantly enhanced the expression of MGMT, and depletion of p53 disrupted the effects of BACH1 on MGMT and temozolomide resistance. P53 sequesters SP1 to prevent its binding to the MGMT promoter region and thus inhibits MGMT expression. Moreover, BACH1 overexpression impaired the association between p53 and SP1 via competitive binding p53, and antagonized the impact of p53 on MGMT expression. Finally, we found that BACH1 low expression correlated with better prognosis in GBM patients undergoing temozolomide therapy, especially in patients with wild-type TP53. Collectively, our findings identify a potential mechanism by which wild-type TP53 GBM cells develop resistance to temozolomide and suggest that targeting this pathway may be beneficial for overcoming resistance. [ABSTRACT FROM AUTHOR]