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1.
Water Res ; 258: 121778, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38795549

RESUMEN

Biotechnology for wastewater treatment is mainstream and effective depending upon microbial redox reactions to eliminate diverse contaminants and ensure aquatic ecological health. However, refractory organic nitrogen compounds (RONCs, e.g., nitro-, azo-, amide-, and N-heterocyclic compounds) with complex structures and high toxicity inhibit microbial metabolic activity and limit the transformation of organic nitrogen to inorganic nitrogen. This will eventually result in non-compliance with nitrogen discharge standards. Numerous efforts suggested that applying exogenous electron donors or acceptors, such as solid electrodes (electrostimulation) and limited oxygen (micro-aeration), could potentially regulate microbial redox reactions and catabolic pathways, and facilitate the biotransformation of RONCs. This review provides comprehensive insights into the microbial regulation mechanisms and applications of electrostimulation and micro-aeration strategies to accelerate the biotransformation of RONCs to organic amine (amination) and inorganic ammonia (ammonification), respectively. Furthermore, a promising approach involving in-situ hybrid anaerobic biological units, coupled with electrostimulation and micro-aeration, is proposed towards engineering applications. Finally, employing cutting-edge methods including multi-omics analysis, data science driven machine learning, technology-economic analysis, and life-cycle assessment would contribute to optimizing the process design and engineering implementation. This review offers a fundamental understanding and inspiration for novel research in the enhanced biotechnology towards RONCs elimination.

2.
Environ Sci Ecotechnol ; 21: 100422, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38746775

RESUMEN

Remediating soil contaminated with polycyclic aromatic hydrocarbons (PAHs) presents a significant environmental challenge due to their toxic and carcinogenic properties. Traditional PAHs remediation methods-chemical, thermal, and bioremediation-along with conventional soil-washing agents like surfactants and cyclodextrins face challenges of cost, ecological harm, and inefficiency. Here we show an effective and environmentally friendly calixarene derivative for PAHs removal through soil washing. Thiacalix[4]arene tetrasulfonate (TCAS) has a unique molecular structure of a sulfonate group and a sulfur atom, which enhances its solubility and facilitates selective binding with PAHs. It forms host-guest complexes with PAHs through π-π stacking, OH-π interactions, hydrogen bonding, van der Waals forces, and electrostatic interactions. These interactions enable partial encapsulation of PAH molecules, aiding their desorption from the soil matrix. Our results show that a 0.7% solution of TCAS can extract approximately 50% of PAHs from contaminated soil while preserving soil nutrients and minimizing adverse environmental effects. This research unveils the pioneering application of TCAS in removing PAHs from contaminated soil, marking a transformative advancement in resource-efficient and sustainable soil remediation strategies.

3.
Water Res ; 258: 121780, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38761598

RESUMEN

Carbon disulfide (CS2) is a widely used enzyme inhibitor with cytotoxic properties, commonly employed in viscose fibers and cellophane production due to its non-polar characteristics. In industry, CS2 is often removed by aeration, however, residual CS2 may enter the wastewater treatment plants, impacting the performance of nitrifying sludge. Currently, there is a notable dearth of research on the response of nitrifying sludge to CS2-induced stress. This study delves into the alterations in the performance of nitrifying sludge under short-term and long-term CS2 stress, scrutinizes the toxic effects of CS2 on microbial cells, elucidates the succession of microbial community structure, and delineates changes in microbial metabolic products. The findings from short-term CS2 stress revealed that low concentrations of CS2 induced oxidative stress damage, which was subsequently repaired in cells. However, at concentrations of 100-200 mg/L, CS2 inhibited reactive oxygen species, superoxide dismutase, and catalase, which are associated with metabolic and antioxidant activities. The inhibition of nitrite oxidoreductase activity by high concentrations of CS2 was attributed to its impact on the enzyme's conformation. Prolonged CS2 stress resulted in an increase in the secretion of soluble extracellular polymeric substances in sludge, while CS2 was assimilated into sulfate. The analysis of sludge microbial community structure revealed a decline in the relative abundance of Rhodanobacter, which is associated with nitrification, and an increase in Sinomonas, involved in sulfur oxidation. Metabolite analysis results demonstrated that high concentrations of CS2 affect pantothenate and CoA biosynthesis, purine metabolism, and glutathione metabolism. This study elucidated the microbial response mechanism of nitrifying sludge under short-term and long-term CS2 stress. It also clarified the composition and function of microbial ecosystems, and identified key bacterial species and metabolites. It provides a basis for future research to reduce CS2 inhibition through approaches such as the addition of metal ions, the selection of efficient CS2-degrading strains, and the modification of strain metabolic pathways.

4.
Environ Sci Ecotechnol ; 20: 100410, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38572083

RESUMEN

Energy recovery from low-strength wastewater through anaerobic methanogenesis is constrained by limited substrate availability. The development of efficient methanogenic communities is critical but challenging. Here we develop a strategy to acclimate methanogenic communities using conductive carrier (CC), electrical stress (ES), and Acid Orange 7 (AO7) in a modified biofilter. The synergistic integration of CC, ES, and AO7 precipitated a remarkable 72-fold surge in methane production rate compared to the baseline. This increase was attributed to an altered methanogenic community function, independent of the continuous presence of AO7 and ES. AO7 acted as an external electron acceptor, accelerating acetogenesis from fermentation intermediates, restructuring the bacterial community, and enriching electroactive bacteria (EAB). Meanwhile, CC and ES orchestrated the assembly of the archaeal community and promoted electrotrophic methanogens, enhancing acetotrophic methanogenesis electron flow via a mechanism distinct from direct electrochemical interactions. The collective application of CC, ES, and AO7 effectively mitigated electron flow impediments in low-strength wastewater methanogenesis, achieving an additional 34% electron recovery from the substrate. This study proposes a new method of amending anaerobic digestion systems with conductive materials to advance wastewater treatment, sustainability, and energy self-sufficiency.

5.
Environ Res ; 252(Pt 1): 118859, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38574986

RESUMEN

Electrocatalytic hydrodechlorination (EHDC) is a promising approach to safely remove halogenated emerging contaminants (HECs) pollutants. However, sluggish production dynamics of adsorbed atomic H (H*ads) limit the applicability of this green process. In this study, bimetallic Pd-Cu@MXene catalysts were synthesized to achieve highly efficient removal of HECs. The alloy electrode (Pd-Cu@MX/CC) exhibited better EHDC performance in comparison to Pd@MX/CC electrode, resulting in diclofenac degradation efficiency of 93.3 ± 0.1%. The characterization analysis revealed that the Pd0/PdII ratio decreased by forming bimetallic Pd-Cu alloy. Density functional theory calculations further demonstrated the electronic configuration modulation of the Pd-Cu@MXene catalysts, optimizing binging energies for H* and thereby facilitating H*ads production and tuning the reduction capability of H*ads. Noteably, the amounts and reduction potential of H*ads for Pd-Cu@MXene catalysts were 1.5 times higher and 0.37 eV lower than those observed for the mono Pd electrode. Hence, the introduction of Cu into the Pd catalyst optimized the dynamics of H*ads production, thereby conferring significant advantages to EHDC reactions. This augmentation was underscored by the successful application of the alloy catalysts supported by MXene in EHDC experiments involving other HECs, which represented a new paradigm for EHDC for efficient recalcitrant pollutant removal by H*ads.

6.
Environ Sci Technol ; 58(9): 4193-4203, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38393778

RESUMEN

Sulfur disproportionation (S0DP) poses a challenge to the robust application of sulfur autotrophic denitrification due to unpredictable sulfide production, which risks the safety of downstream ecosystems. This study explored the S0DP occurrence boundaries with nitrate loading and temperature effects. The boundary values increased with the increase in temperature, exhibiting below 0.15 and 0.53 kg-N/m3/d of nitrate loading at 20 and 30 °C, respectively. A pilot-scale sulfur-siderite packed bioreactor (150 m3/d treatment capacity) was optimally designed with multiple subunits to dynamically distribute the loading of sulfur-heterologous electron acceptors. Operating two active and one standby subunit achieved an effective denitrification rate of 0.31 kg-N/m3/d at 20 °C. For the standby subunit, involving oxygen by aeration effectively transformed the facultative S0DP functional community from S0DP metabolism to aerobic respiration, but with enormous sulfur consumption resulting in ongoing sulfate production of over 3000 mg/L. Meanwhile, acidification by the sulfur oxidation process could reduce the pH to as low as 2.5, which evaluated the Gibbs free energy (ΔG) of the S0DP reaction to +2.56 kJ, thermodynamically suppressing the S0DP occurrence. Therefore, a multisubunit design along with S0DP inhibition strategies of short-term aeration and long-term acidification is suggested for managing S0DP in various practical sulfur-packed bioreactors.


Asunto(s)
Carbonatos , Ecosistema , Compuestos Férricos , Nitratos , Nitratos/metabolismo , Procesos Autotróficos , Temperatura , Azufre/metabolismo , Reactores Biológicos , Desnitrificación , Nitrógeno
7.
Anticancer Agents Med Chem ; 24(5): 389-397, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38192141

RESUMEN

BACKGROUND: Interleukin (IL)-33 is highly expressed in glioblastoma (GBM) and promotes tumor progression. Targeting IL-33 may be an effective strategy for the treatment of GBM. Dexamethasone (DEX) is a controversial drug routinely used clinically in GBM therapy. Whether DEX has an effect on IL-33 is unknown. This study aimed to investigate the effect of DEX on IL-33 and the molecular mechanisms involved. METHODS: U87MG cells were induced by tumor necrosis factor (TNF)-α to express IL-33 and then treated with DEX. The mRNA levels of IL-33, NF-κB p65, ERK1/2, and p38 were determined by real-time quantitative PCR. The expression of IL-33, IkBα (a specific inhibitor of NF-κB) and MKP-1 (a negative regulator of MAPK), as well as the phosphorylation of NF-κB, ERK1/2 and p38 MAPK, were detected by Western blotting. The secretion of IL-33 was measured by ELISA. The proliferation, migration and invasion of U87MG cells were detected by CCK8 and transwell assays, respectively. RESULTS: DEX significantly reduced TNF-α-induced production of IL-33 in U87MG cells, which was dependent on inhibiting the activation of the NF-κB, ERK1/2 and p38 MAPK signaling pathways, and was accompanied by the increased expression of IkBα but not MKP-1. Furthermore, the proliferation, migration and invasion of U87MG cells exacerbated by IL-33 were suppressed by DEX. CONCLUSION: DEX inhibited the production and tumor-promoting function of IL-33. Whether DEX can benefit GBM patients remains controversial. Our results suggest that GBM patients with high IL-33 expression may benefit from DEX treatment and deserve further investigation.


Asunto(s)
Glioblastoma , FN-kappa B , Humanos , FN-kappa B/metabolismo , Sistema de Señalización de MAP Quinasas , Glioblastoma/tratamiento farmacológico , Interleucina-33/genética , Interleucina-33/metabolismo , Transducción de Señal , Factor de Necrosis Tumoral alfa , Dexametasona/farmacología , Proteínas Quinasas p38 Activadas por Mitógenos , Fenotipo
8.
J Hazard Mater ; 465: 133438, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38198865

RESUMEN

Given widespread presence of polystyrene (PS) microplastics/nanoplastics (MPs/NPs), the electroactive responses and adaptation mechanisms of electroactive biofilms (EABs) exposed long-term to PS-containing aquatic environments remain unclear. Therefore, this study investigated the impacts of PS MPs/NPs on electroactivity of EABs. Results found that EABs exhibited delayed formation upon initially exposure but displayed an increased maximum current density (Imax) after subsequent exposure for up to 55 days. Notably, EABs exposure to NH2PS NPs (EAB-NH2PSNPs) demonstrated a 50% higher Imax than the control, along with a 17.84% increase in viability and a 58.10% increase in biomass. The cytochrome c (c-Cyts) content in EAB-NH2PSNPs rose by 178.35%, benefiting the extracellular electron transfer (EET) of EABs. Moreover, bacterial community assembly indicated the relative abundance of electroactive bacteria increased to 87.56% in EAB-NH2PSNPs. The adaptability mechanisms of EABs under prolonged exposure to PS MPs/NPs predominantly operate by adjusting viability, EET, and bacterial community assembly, which were further confirmed a positive correlation with Imax through structural equation model. These findings provide deeper insights into long-term effects and mechanisms of MPs/NPs on the electroactive properties of EABs and even functional microorganisms in aquatic ecosystems.


Asunto(s)
Microplásticos , Poliestirenos , Plásticos , Ecosistema , Biopelículas
9.
Bioresour Technol ; 393: 130081, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37993067

RESUMEN

The sulfur fluidizing bioreactor (S0FB) has significant superiorities in treating nitrate-rich wastewater. However, substantial self-acidification has been observed in engineering applications, resulting in frequent start-up failures. In this study, self-acidification was reproduced in a lab-scale S0FB. It was demonstrated that self-acidification was mainly induced by sulfur disproportionation process, accounting for 93.4 % of proton generation. Supplying sufficient alkalinity to both the influent (3000 mg/L) and the bulk (2000 mg/L) of S0FB was essential for achieving a successful start-up. Furthermore, the S0FB reached 10.3 kg-N/m3/d of nitrogen removal rate and 0.13 kg-PO43-/m3/d of phosphate removal rate, respectively, surpassing those of the documented sulfur packing bioreactors by 7-129 times and 26-65 times. This study offers a feasible and practical method to avoid self-acidification during restart of S0FB and highlights the considerable potential of S0FB in the treatment of nitrate-rich wastewater.


Asunto(s)
Nitratos , Aguas Residuales , Procesos Autotróficos , Desnitrificación , Azufre , Reactores Biológicos , Concentración de Iones de Hidrógeno , Nitrógeno
10.
Water Res ; 249: 120915, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38029487

RESUMEN

Utilizing H2-assisted ex-situ biogas upgrading and acetate recovery holds great promise for achieving high value utilization of biogas. However, it faces a significant challenge due to acetate's high solubility and limited economic value. To address this challenge, we propose an innovative strategy for simultaneous upgrading of biogas and the production of medium-chain fatty acids (MCFAs). A series of batch tests evaluated the strategy's efficiency under varying initial gas ratios (v/v) of H2, CH4, CO2, along with varying ethanol concentrations. The results identified the optimal conditions as initial gas ratios of 3H2:3CH4:2CO2 and an ethanol concentration of 241.2 mmol L-1, leading to maximum CH4 purity (97.2 %), MCFAs yield (54.2 ± 2.1 mmol L-1), and MCFAs carbon-flow distribution (62.3 %). Additionally, an analysis of the microbial community's response to varying conditions highlighted the crucial roles played by microorganisms such as Clostridium, Proteiniphilum, Sporanaerobacter, and Bacteroides in synergistically assimilating H2 and CO2 for MCFAs production. Furthermore, a 160-day continuous operation using a dual-membrane aerated biofilm reactor (dMBfR) was conducted. Remarkable achievements were made at a hydraulic retention time of 2 days, including an upgraded CH4 content of 96.4 ± 0.3 %, ethanol utilization ratio (URethanol) of 95.7 %, MCFAs production rate of 28.8 ± 0.3 mmol L-1 d-1, and MCFAs carbon-flow distribution of 70 ± 0.8 %. This enhancement is proved to be an efficient in biogas upgrading and MCFAs production. These results lay the foundation for maximizing the value of biogas, reducing CO2 emissions, and providing valuable insights into resource recovery.


Asunto(s)
Biocombustibles , Reactores Biológicos , Dióxido de Carbono , Metano , Biopelículas , Acetatos , Carbono , Etanol , Ácidos Grasos
11.
Water Res ; 246: 120676, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37806124

RESUMEN

Intelligent control of wastewater treatment plants (WWTPs) has the potential to reduce energy consumption and greenhouse gas emissions significantly. Machine learning (ML) provides a promising solution to handle the increasing amount and complexity of generated data. However, relationships between the features of wastewater datasets are generally inconspicuous, which hinders the application of artificial intelligence (AI) in WWTPs intelligent control. In this study, we develop an automatic framework of feature engineering based on variation sliding layer (VSL) to control the air demand precisely. Results demonstrated that using VSL in classic machine learning, deep learning, and ensemble learning could significantly improve the efficiency of aeration intelligent control in WWTPs. Bayesian regression and ensemble learning achieved the highest accuracy for predicting air demand. The developed models with VSL-ML models were also successfully implemented under the full-scale wastewater treatment plant, showing a 16.12 % reduction in demand compared to conventional aeration control of preset dissolved oxygen (DO) and feedback to the blower. The VSL-ML models showed great potential to be applied for the precision air demand prediction and control. The package as a tripartite library of Python is called wwtpai, which is freely accessible on GitHub and CSDN to remove technical barriers to the application of AI technology in WWTPs.


Asunto(s)
Eliminación de Residuos Líquidos , Purificación del Agua , Eliminación de Residuos Líquidos/métodos , Inteligencia Artificial , Teorema de Bayes , Aprendizaje Automático , Purificación del Agua/métodos
12.
J Biol Chem ; 299(11): 105335, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37827291

RESUMEN

Hepatoma-derived growth factor (HDGF) overexpression and uncontrolled reactive oxygen species (ROS) accumulation are involved in malignant transformation and poor prognosis in various types of cancer. However, the interplay between HDGF and ROS generation has not been elucidated in hepatocellular carcinoma. Here, we first analyzed the profile of HDGF expression and ROS production in newly generated orthotopic hepatomas by ultrasound-guided implantation. In situ superoxide detection showed that HDGF-overexpressing hepatomas had significantly elevated ROS levels compared with adjacent nontumor tissues. Consistently, liver tissues from HDGF-deficient mice exhibited lower ROS fluorescence than those from age- and sex-matched WT mice. ROS-detecting fluorescent dyes and flow cytometry revealed that recombinant HDGF (rHDGF) stimulated the production of superoxide anion, hydrogen peroxide, and mitochondrial ROS generation in cultured hepatoma cells in a dose-dependent manner. In contrast, the inactive Ser103Ala rHDGF mutant failed to promote ROS generation or oncogenic behaviors. Seahorse metabolic flux assays revealed that rHDGF dose dependently upregulated bioenergetics through enhanced basal and total oxygen consumption rate, extracellular acidification rate, and oxidative phosphorylation in hepatoma cells. Moreover, antioxidants of N-acetyl cysteine and MitoQ treatment significantly inhibited HDGF-mediated cell proliferation and invasive capacity. Genetic silencing of superoxide dismutase 2 augmented the HDGF-induced ROS generation and oncogenic behaviors of hepatoma cells. Finally, genetic knockdown nucleolin (NCL) and antibody neutralization of surface NCL, the HDGF receptor, abolished the HDGF-induced increase in ROS and mitochondrial energetics. In conclusion, this study has demonstrated for the first time that the HDGF/NCL signaling axis induces ROS generation by elevating ROS generation in mitochondria, thereby stimulating liver carcinogenesis.


Asunto(s)
Carcinoma Hepatocelular , Animales , Ratones , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Especies Reactivas de Oxígeno , Carcinogénesis/genética
13.
Nat Commun ; 14(1): 6877, 2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-37898608

RESUMEN

Three-component dehydrogenative coupling reactions represent important and practical methodologies for forging new C-N bonds and C-C bonds. Achieving highly all-in-one dehydrogenative coupling functionalization by a single catalytic system remains a great challenge. Herein, we develop a rigid-flexible-coupled copper cluster [Cu3(NHC)3(PF6)3] (Cu3NC(NHC)) using a tridentate N-heterocyclic carbene ligand. The shell ligand endows Cu3NC(NHC) with dual attributes, including rigidity and flexibility, to improve activity and stability. The Cu3NC(NHC) is applied to catalyze both highly all-in-one dehydrogenative coupling transformations. Mechanistic studies and density functional theory illustrate that the improved regioselectivity is derived from the low energy of ion pair with copper acetylide and endo-iminium ions and the low transition state, which originates from the unique physicochemical properties of the Cu3NC(NHC) catalyst. This work highlights the importance of N-heterocyclic carbene in the modification of copper clusters, providing a new design rule to protect cluster catalytic centers and enhance catalysis.

14.
J Hazard Mater ; 459: 132183, 2023 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-37531766

RESUMEN

Electroactive biofilms (EABs) play a crucial role in environmental bioremediation due to their excellent extracellular electron transfer (EET) capabilities. However, Cd2+ can have toxic effects on the electrochemical performance of EABs, and the comprehensive inhibition mechanism of EABs in response to Cd2+ shock remains elusive. This study indicated that Cd2+ shock significantly reduced biomass and increased oxidative stress in EABs at the cellular level. The bacterial viability of EABs in phase III under 0.5 mM Cd2+ shock (EABCd2+-III0.5) decreased by 16.31% compared to EABCK-III. Moreover, intracellular NADH, c-Cyts, and the abundance of electroactive species were essential indicators to evaluate EET behavior of EABs. In EABCd2+-III0.5, these indicators decreased by 26.32%, 33.40%, and 20.65%, respectively. Structural equation modeling analysis established quantitative correlations between core components and electrochemical activity at cellular and community levels. The correlation analysis revealed that the growth and electron transfer functions of EABs were predictive indicators for their electrochemical performance, with standardized path coefficients of 0.407 and 0.358, respectively. These findings enhance our understanding of EABs' response to Cd2+ shock and provide insights for improving their performance in heavy metal wastewater.


Asunto(s)
Cadmio , Geobacter , Cadmio/toxicidad , Viabilidad Microbiana , Electrones , Electrodos , Biopelículas
15.
Environ Pollut ; 334: 122081, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37414118

RESUMEN

The coexistence of antibiotics and heavy metals in agroecosystems is nonnegligible, which permits the promotion of antibiotic resistance genes (ARGs) in crops, thus posing a potential threat to humans along the food chain. In this study, we investigated the bottom-up (rhizosphere→rhizome→root→leaf) long-distance responses and bio-enrichment characteristics of ginger to different sulfamethoxazole (SMX) and chromium (Cr) contamination patterns. The results showed that ginger root systems adapted to SMX- and/or Cr-stress by increasing humic-like exudates, which may help to maintain the rhizosphere indigenous bacterial phyla (i.e., Proteobacteria, Chloroflexi, Acidobacteria and Actinobacteria). The root activity, leaf photosynthesis and fluorescence, and antioxidant enzymes (SOD, POD, CAT) of ginger were significantly decreased under high-dose Cr and SMX co-contamination, while a "hormesis effect" was observed under single low-dose SMX contamination. For example, CS100 (co-contamination of 100 mg/L SMX and 100 mg/L Cr) caused the most severe inhibition to leaf photosynthetic function by reducing photochemical efficiency (reflected on PAR-ETR, φPSII and qP). Meanwhile, CS100 induced the highest ROS production, in which H2O2 and O2·- increased by 328.82% and 238.00% compared with CK (the blank control without contamination). Moreover, co-selective stress by Cr and SMX induced the increase of ARG bacterial hosts and bacterial phenotypes containing mobile elements, contributing to the high detected abundance of target ARGs (sul1, sul2) up to 10-2∼10-1 copies/16S rRNA in rhizomes intended for consumption.


Asunto(s)
Antibacterianos , Zingiber officinale , Humanos , Antibacterianos/farmacología , Sulfametoxazol , Zingiber officinale/genética , Suelo , Cromo/toxicidad , ARN Ribosómico 16S , Peróxido de Hidrógeno , Bacterias/genética , Genes Bacterianos , Farmacorresistencia Microbiana/genética
16.
Water Res ; 243: 120356, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37516076

RESUMEN

Elemental sulfur packed-bed (S0PB) bioreactors for autotrophic denitrification have gained more attention in wastewater treatment due to their organic carbon-free operation, low operating cost, and minimal carbon emissions. However, the rapid development of microbial S0-disproportionation (MS0D) in S0PB reactor during deep denitrification poses a significant drawback to this new technology. MS0D, the process in which sulfur is used as both an electron donor and acceptor by bacteria, plays a crucial role in the microbial-driven sulfur cycle but remains poorly understood in wastewater treatment setups. In this study, we induced MS0D in a pilot-scale S0PB reactor capable of denitrifying over 1000 m3/d nitrate-containing wastewater. Initially, the S0PB reactor stably removed 6.6 mg-NO3--N/L nitrate at an empty bed contact time (EBCT) of 20 mins, which was designated the S0-denitrification stage. To induce MS0D, we reduced the influent nitrate concentrations to allow deep nitrate removal, resulted in the production of large quantities of sulfate and sulfide (SO42-:S2- 3.2 w/w). Meanwhile, other sulfur-heterologous electron acceptors (SHEAs), e.g., nitrite and DO, were also kept at trace levels. The negative correlations between the SHEAs concentrations and the sulfide productions indicated that the absence of SHEAs was a primary inducing factor to MS0D. The microbial community drastically diverged in response to the depletion of SHEAs during the switch from S0-denitrification to S0-disproportionation. An evident enrichment of sulfur-disproportionating bacteria (SDBs) was found at the S0-disproportionation stage, accompanied by the decline of sulfur-oxidizing bacteria (SOBs). In the end, we discovered that shortening the EBCT and increasing the reflux ratio could inhibit sulfide production by reducing it from 43.9 mg/L to 3.2 mg/L or 25.5 mg/L. In conclusion, our study highlights the importance of considering MS0D when designing and optimizing S0PB reactors for sustainable autotrophic sulfur denitrification in real-life applications.


Asunto(s)
Desnitrificación , Nitratos , Procesos Autotróficos , Azufre , Reactores Biológicos/microbiología , Bacterias , Sulfuros , Nitrógeno
17.
J Hazard Mater ; 459: 132113, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37487329

RESUMEN

In this study, a Pd@MXene catalyst was synthesized to enhance the electrocatalytic hydrodehalogenation (ECH) of emerging halogenated organic pollutants (HOPs) by improving the dispersibility, catalytic activity, and stability of palladium (Pd). The average size of Pd nanoparticles (NPs) was reduced to 3.62 ± 0.34 nm with a more intensive peak of Pd (111), which facilitated atomic hydrogen (H*) production. The Pd@MX/CC electrode demonstrated superior ECH activity for diclofenac (DCF) degradation, with a reaction rate constant (kobs) 2.48 times higher than that of Pd/CC (without MXene). The satisfactory ECH performance of Pd@MX/CC remained consistent within a wide range of initial DCF concentrations (5-100 mg/L), and no significant ECH attenuation was observed even after up to 10 batches. Furthermore, the high activity of Pd@MX/CC was also observed in the ECH of other halogenated organic pollutants (levofloxacin, tetrabromobisphenol A, and diatrizoate). Density functional theory (DFT) calculations revealed that electronic configuration modulation of the Pd@MXene catalyst optimized binging energies to H* , DCF, and dechlorinated products, thereby enhancing the ECH efficiency of DCF.

18.
Front Cell Dev Biol ; 11: 1168462, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37469574

RESUMEN

Background: Kidney renal clear cell carcinoma (KIRC) is an immunogenic tumor, and immune infiltrates are relevant to patients' therapeutic response and prognosis. NDUFS1, the core subunit of mitochondrial complex I, has been reported to be associated with KIRC patients' prognosis. However, the upstream regulator for NDUFS1 and their correlations with immune infiltration remain unclear. Methods: The expression of NDUFS genes in KIRC and their influences on patients' survival were investigated by UALCAN, ENCORI, Oncomine, TIMER as well as Kaplan-Meier Plotter. miRNAs regulating NDUFS1 were predicted and analyzed by TargetScan and ENCORI. The correlations between NDUFS1 expression and immune cell infiltration or gene marker sets of immune infiltrates were analyzed via TIMER. The overall survival in high/low NDUFS1 or hsa-miR-320b expressed KIRC patients with or without immune infiltrates were analyzed via Kaplan-Meier Plotter. The combined NDUFS1 expression and/or CD4+ T cell infiltration on KIRC patients' overall survival were validated by multiplexed immunofluorescence (mIF) staining in tissue microarray (TMA). Furthermore, the influences of NDUFS1 expression on the chemotaxis of CD4+ T cells to KIRC cells were performed by transwell migration assays. Results: We found that the low expression of NDUFS1 mRNA and protein in KIRC was correlated with unfavorable patients' survival and poor infiltration of CD4+ T cells. In patients with decreased CD4+ T cell infiltration whose pathological grade less than III, TMA mIF staining showed that low expression of NDUFS1 had significantly poor OS than that with high expression of NDUFS1 did. Furthermore, hsa-miR-320b, a possible negative regulator of NDUFS1, was highly expressed in KIRC. And, low NDUFS1 or high hsa-miR-320b consistently correlated to unfavorable outcomes in KIRC patients with decreased CD4+ T cell infiltration. In vitro, NDUFS1 overexpression significantly increased the chemotaxis of CD4+ T cell to KIRC cells. Conclusion: Together, NDUFS1, upregulated by decreased hsa-miR-320b expression in KIRC patients, might act as a biomarker for CD4+ T cell infiltration. And, the combination of NDUFS1 with CD4+ T cell infiltration predicts favorable prognosis in KIRC.

19.
Front Cardiovasc Med ; 10: 1095960, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37324628

RESUMEN

Background: Percutaneous coronary intervention for in-stent restenosis (ISR) chronic total occlusion (CTO) has been a great challenge. There are occasions when the balloon is uncrossable or undilatable (BUs) even though the guidewire has passed, leading to failure of the procedure. Few studies have focused on the incidence, predictors, and management of BUs during ISR-CTO intervention. Methods: Patients with ISR-CTO were recruited consecutively between January 2017 and January 2022 and divided into two groups based on the presence of BUs. The clinical data of the two groups (BUs group and non-BUs group) were retrospectively analyzed and compared to explore the predictors and clinical management strategies of BUs. Results: A total of 218 patients with ISR-CTO were included in this study, 23.9% (52/218) of whom had BUs. The percentage of ostial stents, stent length, CTO length, the presence of proximal cap ambiguity, moderate to severe calcification, moderate to severe tortuosity, and J-CTO score were higher in the BUs group than in the non-BUs group (p < 0.05). The technical success rate and the procedural success rate were lower in the BUs group than in the non-BUs group (p < 0.05). Multivariable logistic regression analysis showed that ostial stents (OR: 2.011, 95% CI: 1.112-3.921, p = 0.031), the presence of moderate to severe calcification (OR: 3.383, 95% CI: 1.628-5.921, p = 0.024) and moderate to severe tortuosity (OR: 4.816, 95% CI: 2.038-7.772, p = 0.033) were independent predictors of BUs. Conclusion: The initial rate of BUs in ISR-CTO was 23.9%. Ostial stents, presence of moderate to severe calcification, and moderate to severe tortuosity were independent predictors of BUs.

20.
Bioresour Technol ; 382: 129121, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37146695

RESUMEN

In this work, the bioelectrochemical system (BES) is a feasible alternative for successfully degrading typical refractory emerging contaminant triclosan (TCS). A single-chamber BES reactor with an initial TCS concentration of 1 mg/L, an applied voltage of 0.8 V, and a solution buffered with 50 mM PBS degraded 81.4 ± 0.2% of TCS, exhibiting TCS degradation efficiency improvement to 90.6 ± 0.2% with a biocathode formed from a reversed bioanode. Both bioanode and biocathode were able to degrade TCS with comparable efficiencies of 80.8 ± 4.9% and 87.3 ± 0.4%, respectively. Dechlorination and hydrolysis were proposed as the TCS degradation pathway in the cathode chamber, and another hydroxylation pathway was exclusive in the anode chamber. Microbial community structure analysis indicated Propionibacteriaceae was the predominant member in all electrode biofilms, and the exoelectrogen Geobacter was enriched in anode biofilms. This study comprehensively revealed the feasibility of operating BES technology for TCS degradation.


Asunto(s)
Triclosán , Electrodos
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