RESUMO
To explore the feasibility of biofilter reactor to treat municipal secondary effluent deeply without extra carbon source, this paper proposed an integrated biofilter reactor (IBFR) coupling partial denitrification (PD) with anammox (A) to treat the secondary effluent and raw sewage with the flow ratio of 3:1 together. The results show that the effluent concentration of TN and COD in IBFR could be reduced to 10 mg/L and 15 mg/L, respectively, under hydraulic retention time of 1.5 h and nitrogen loading rate of 0.55 kg/(m3·d). The highest specific anammox activity (19.2 mg N/(g TVS·d)) and the maximum extracellular polymeric substance (EPS) content (107.21 mg/g TVS) occurred at the 25-50 cm section of IBFR, where Thauera, Candidatus Anammoximicrobium and Candidatus Brocadia were the dominant denitrifiers and anammox bacteria. Furthermore, the cyclic self-stratification occurred along the reactor height, where the utilization, decomposition, transformation and cross-feeding of EPS enhanced the performance stability of nitrogen and carbon removal, strengthened the niche structure and promoted the synergistic symbiosis. In conclusion, IBFR coupling PD and A demonstrated the possibility to treat secondary effluent without additional carbon sources, which is expected as an alternative approach for tertiary treatment of municipal wastewater.
Assuntos
Desnitrificação , Águas Residuárias , Matriz Extracelular de Substâncias Poliméricas , Reatores Biológicos , Oxirredução , Esgotos , Nitrogênio , CarbonoRESUMO
Recent studies show that greenhouse gas (GHG) emissions from urban landscape water are significant and cannot be overlooked, underscoring the need to develop effective strategies for mitigating GHG production from global freshwater systems. Calcium peroxide (CaO2) is commonly used as an eco-friendly reagent for controlling eutrophication in water bodies, but whether CaO2 can reduce GHG emissions remains unclear. This study investigated the effects of CaO2 dosage on the production of methane (CH4) and nitrous oxide (N2O) in urban landscape water under anoxic conditions during summer. The findings reveal that CaO2 addition not only improved the physicochemical and organoleptic properties of simulated urban landscape water but also reduced N2O production by inhibiting the activity of denitrifying bacteria across various dosages. Moreover, CaO2 exhibited selective effects on methanogens. Specifically, the abundance of acetoclastic methanogen Methanosaeta and methylotrophic methanogen Candidatus_Methanofastidiosum increased whereas the abundance of the hydrogenotrophic methanogen Methanoregula decreased at low, medium, and high dosages, leading to higher CH4 production at increased CaO2 dosage. A comprehensive multi-objective evaluation indicated that an optimal dosage of 60 g CaO2/m2 achieved 41.21 % and 84.40 % reductions in CH4 and N2O production, respectively, over a 50-day period compared to the control. This paper not only introduces a novel approach for controlling the production of GHGs, such as CH4 and N2O, from urban landscape water but also suggests a methodology for optimizing CaO2 dosage, providing valuable insights for its practical application.
Assuntos
Metano , Óxido Nitroso , Peróxidos , Qualidade da Água , Metano/análise , Óxido Nitroso/análise , Peróxidos/análise , Poluentes Químicos da Água/análise , Gases de Efeito Estufa/análiseRESUMO
Sediment re-suspension plays a crucial role in releasing endogenous nitrogen and greenhouse gases in shallow urban waters. However, the impacts of repeated re-suspension and photo-induced processes on migration and transformation from endogenous nitrogen, as well as the emission of greenhouse gases, remain unclear. This study simulated three conditions: re-suspension (Rs), re-suspension combined with ultravioletirradiation (Rs + UV), and ultraviolet irradiation (UV). The findings revealed that both repeated sediment re-suspension and exposure to UV light altered the characteristics of surface sediments. Decrease of convertible nitrogen in sediments, leading to the release of ion-exchangeable nitrogen (IEF-N) into NH4+-N and NO3--N, influenced greenhouse gas production differently under various conditions. The study observed the highest concentration of dissolved N2O in under UV irradiation, positively correlated with NO2--N and NO3--N. Re-suspension increased the turbidity of the overlying water and accelerated nitrification, resulting in the highest NO3--N concentration and the lowest dissolved N2O concentration. Additionally, in the Rs + UV dissolved N2O maintained the higher concentrations than in Rs, with greatest amount of N conversion in surface sediments, and a 59.45% reduction in IEF-N. The production of N2O during re-suspension was mainly positively correlated with NH4+-N in the overlying water. Therefore, this study suggest that repeated re-suspension and light exposure significantly influence nitrogen migration and transformation processes in sediment, providing a theoretical explanation for the eutrophication of water and greenhouse gas emissions.
Assuntos
Nitrogênio , Nitrogênio/análise , Raios Ultravioleta , Poluentes Químicos da Água/análiseRESUMO
Repositioning approved antitumor drugs for different cancers is a cost-effective approach. Gilteritinib was FDA-approved for the treatment of FLT3-mutated acute myeloid leukemia in 2018. However, the therapeutic effects and mechanism of Gilteritinib on other malignancies remain to be defined. In this study, we identified that gilteritinib has an inhibitory effect on lung cancer cells (LCCs) without FLT3 mutation in vitro and in vivo. Unexpectedly, we found that gilteritinib induces cholesterol accumulation in LCCs via upregulating cholesterol biosynthetic genes and inhibiting cholesterol efflux. This gilteritinib-induced cholesterol accumulation not only attenuates the antitumor effect of gilteritinib but also induces gilteritinib-resistance in LCCs. However, when cholesterol synthesis was prevented by squalene epoxidase (SQLE) inhibitor NB-598, both LCCs and gilteritinib-resistant LCCs became sensitive to gilteritinib. More importantly, the natural cholesterol inhibitor 25-hydroxycholesterol (25HC) can suppress cholesterol biosynthesis and increase cholesterol efflux in LCCs. Consequently, 25HC treatment significantly increases the cytotoxicity of gilteritinib on LCCs, which can be rescued by the addition of exogenous cholesterol. In a xenograft model, the combination of gilteritinib and 25HC showed significantly better efficacy than either monotherapy in suppressing lung cancer growth, without obvious general toxicity. Thus, our findings identify an increase in cholesterol induced by gilteritinib as a mechanism for LCC survival, and highlight the potential of combining gilteritinib with cholesterol-lowering drugs to treat lung cancer.
Assuntos
Compostos de Anilina , Colesterol , Neoplasias Pulmonares , Éteres Fenílicos , Pirazinas , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/metabolismo , Colesterol/metabolismo , Colesterol/biossíntese , Animais , Pirazinas/farmacologia , Linhagem Celular Tumoral , Camundongos , Compostos de Anilina/farmacologia , Compostos de Anilina/uso terapêutico , Éteres Fenílicos/farmacologia , Éteres Fenílicos/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Camundongos Nus , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , FemininoRESUMO
The androgen receptor (AR) plays an important role in male-dominant hepatocellular carcinoma, and specific acquired somatic mutations of AR have been observed in HCC patients. Our previous research have established the role of AR wild type as one of the key oncogenes in hepatocarcinogenesis. However, the role of hepatic acquired somatic mutations of AR remains unknown. In this study, we identify two crucial acquired somatic mutations, Q62L and E81Q, situated close to the N-terminal activation function domain-1 of AR. These mutations lead to constitutive activation of AR, both independently and synergistically with androgens, making them potent driver oncogene mutations. Mechanistically, these N-terminal AR somatic mutations enhance de novo lipogenesis by activating sterol regulatory element-binding protein-1 and promote glycogen accumulation through glycogen phosphorylase, brain form, thereby disrupting the AMPK pathway and contributing to tumorigenesis. Moreover, the AR mutations show sensitivity to the AMPK activator A769662. Overall, this study establishes the role of these N- terminal hepatic mutations of AR as highly malignant oncogenic drivers in hepatocarcinogenesis and highlights their potential as therapeutic targets for patients harboring these somatic mutations.
Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Receptores Androgênicos , Humanos , Masculino , Proteínas Quinases Ativadas por AMP , Carcinogênese/genética , Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , Mutação , Receptores Androgênicos/genéticaRESUMO
Circular RNAs (circRNAs) are covalently closed, single-stranded RNAs that play critical roles in various biological processes and diseases, including cancers. However, the functions and mechanisms of circRNAs in hepatocellular carcinoma (HCC) need further clarification. Here, we identified and confirmed that circATF6 is downregulated in HCC tissues and negatively associated with the overall survival of HCC patients. Ectopic overexpression of circATF6 inhibits malignant phenotypes of HCC cells in vitro and in vivo, while knockdown of circATF6 had opposite effects. Mechanistically, we found that circATF6 bound to calreticulin (CALR) protein and acted as a scaffold to enhance the interaction of CALR with calpain2 (CAPN2), which promoted the degradation of CALR by its enzymatic activity. Moreover, we found that circATF6 inhibited HCC cells by suppressing CALR-mediated wnt/ß-catenin signaling pathway. Taken together, our findings suggest that circATF6 is a potential prognostic biomarker and therapeutic target for HCC.