RESUMO
Anaerobic ammonium oxidation (ANAMMOX), as its essential advantages of high efficiency and low cost, is a promising novel biological nitrogen elimination process with attractive application prospects. Over the past two decades, many processes based on the ANAMMOX reaction have been continuously studied and applied to practical engineering, with the perspective of reaching 100 full-scale installations in operation worldwide by 2014. Our review summarizes various forms of ANAMMOX processes, including partial nitritation-ANAMMOX, completely autotrophic nitrogen removal over nitrite, oxygen limited autotrophic nitrification and denitrification, denitrifying ammonium oxidation, aerobic deammonification, simultaneous partial nitrification, ANAMMOX and denitrification, single-stage nitrogen removal using ANAMMOX and partial nitritation. We also compare the operating conditions for one-stage and two-stage processes and summarize the obstacles and countermeasures in engineering application of ANAMMOX systems, such as moving bed biofilm reactor, sequencing batch reactor and granular sludge reactor. Finally, we discuss the future research and application direction, which should focus on the optimization of operating conditions and applicability of the process to the actual wastewater, especially on automated control and the impact of special wastewater composition on process performance.
Assuntos
Amônia , Química , Reatores Biológicos , Desnitrificação , Nitrificação , Nitritos , Química , Nitrogênio , Química , Oxigênio , Química , Esgotos , Química , Eliminação de Resíduos Líquidos , Métodos , Águas Residuárias , QuímicaRESUMO
In order to investigate the roles of MTA2 in the pathogenesis of ovarian epithelial cancer, the expression of MTA2 in 4 ovarian cell lines were detected by semi-quantitative RT-PCR and Western-blot assays. MTA2 expression in normal, borderline, benign and malignant epithelial ovarian tissues was immunohistochemically examined. The expression of MTA2 mRNA and protein was detected in all of 4 cell lines of ovarian epithelial cancer. The expression of MTA2 mRNA and protein was higher in strong migration cell lines than in weak migration ones. In borderline and malignant ovarian tissues tested, MTA2 staining was dramatically stronger than in normal and benign tissues (P < 0.01). The expression levels in malignant ovarian tissues were significantly higher than that in borderline epithelial ovarian tissues (P < 0.01). The expression of MTA2 was correlated with clinical stage, histopathological grade and lymph node metastasis. It was concluded that the high expression of MTA2 was associated with more aggressive behaviors of epithelial ovarian cancer. MTA2 provides a novel indicator of ovarian cancer.
RESUMO
In order to investigate the roles of MTA2 in the pathogenesis of ovarian epithelial cancer, the expression of MTA2 in 4 ovarian cell lines were detected by semi-quantitative RT-PCR and Western-blot assays. MTA2 expression in normal, borderline, benign and malignant epithelial o varian tissues was immunohistochemically examined. The expression of MTA2 mRNA and protein was detected in all of 4 cell lines of ovarian epithelial cancer. The expression of MTA2 mRNA and protein was higher in strong migration cell lines than in weak migration ones. In borderline and malignant ovarian tissues tested, MTA2 staining was dramatically stronger than in normal and benign tissues (P＜0.01). The expression levels in malignant ovarian tissues were significantly higher than that in borderline epithelial ovarian tissues (P＜0.01). The expression of MTA2 was correlated with clinical stage, histopathological grade and lymph node metastasis. It was concluded that the high expression of MTA2 was associated with more aggressive behaviors of epithelial ovarian cancer. MTA2 provides a novel indicator of ovarian cancer.
