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Peroxisome proliferator-activator receptor (PPAR) γ is a nuclear hormone receptor that regulates glucose homeostasis, lipid metabolism, and adipocyte function. It has been shown that activation of PPARγ can reduce the incidence of gallstone. Herein we aimed to clarify the role of PPARγ in the reduction of gallstones. The plasmid containing the coding sequence of PPARγ was constructed and transfected in the human liver cell line (L02 cells). Western blot and RT-PCR were used to detect hydroxyl-methyl-glutaryl-CoA reductase (HMGCR), sterol regulatory element-binding proteins 2 (SREBP2), 7α-hydroxylase (CYP7A1), adenosine triphosphate-binding cassette (ABC) sterol transporters G5 and G8 (ABCG5, ABCG8) and liver X receptor α (LXRα). The Amplex Red cholesterol assay kit was used to detect the intracellular or extracellular cholesterol level. Our data showed that PPARγ overexpression caused significant decreases in both extracellular and intracellular cholesterol in the L02 cells. The further studies indicated PPARγ overexpression substantially decreased expression of HMGCR and SREBP-2, increased expression of CYP7A1, ABCG5, ABCG8 and LXRα. These results indicated that upregulation of PPARγ may reduce cholesterol levels through multiple-pathways including HMGCR/SREBP2-mediated biosynthesis, CYP7A1-mediated transformation, and ABCG5/ABCG8-mediated efflux. We thus suggest that PPARγ might have beneficial effects for cholesterol gallstones diseases. Keywords: PPARγ, Cholesterol, HMGCR, CYP7A1 and ABCG5/8

Monitoring only 16 priority PAHs (Pri-PAHs) may greatly underestimate the pollutant load and toxicity of polycyclic aromatic compounds (PACs) in aquatic environments. There is an urgent need to reevaluate the list of priority PACs. To determine which PACs deserve priority monitoring, the occurrence, sources, and toxicity of 78 PACs, including 24 parent PAHs (Par-PAHs), 49 alkylated PAHs (Alk-PAHs), 3 oxygenated PAHs (OPAHs), carbazole, and dibenzothiophene were investigated for the first time in Lake Chaohu sediments, China. Concentrations of ∑Par-PAHs, ∑Alk-PAHs, and ∑OPAHs ranged from 35 to 165, 3.4-26, and 7.7-26 ng g -1 , respectively. Concentrations of 16 Pri-PAHs have decreased by 1-2 orders of magnitude compared to a decade ago, owing to the effective implementation of PAHs emission control measures. Comparisons with the sediment quality guidelines indicated that 16 Pri-PAHs have negligible adverse effects on benthic organisms. Positive matrix factorization (PMF) model results showed that coal combustion was the major source of PACs (accounting for 23.5 %), followed by traffic emissions (23.4 %), petroleum volatilization (21.9 %), wood/biomass combustion (18.2 %), and biological/microbial transformation (13.1 %). The toxicity of PACs was assessed by calculating the BaP toxic equivalent concentrations (TEQ BaP ) and toxic units. It was found that Par-PAHs were the predominant toxic substances. In addition, monomethyl-BaPs, OPAHs, BeP, and 7,12-DMBaA should be prioritized for monitoring due to their noticeable contributions to overall toxicity. The contributions of different sources to the toxicity of PACs were determined based on PMF model results and TEQ BaP values, which revealed that combustion sources mainly contributed to the comprehensive toxicity of PACs in Lake Chaohu sediments., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Soil organic matter (SOM) and clay minerals are important sinks for reactive heavy metals (HMs) and exogenous hydrogen ions (H + ). Therefore, HMs are likely to be released into soil porewater under acid rainfall conditions due to the competitive adsorption of H + . However, negligible Lead, Zinc, and Cadmium (<6 ‰) in the Pb/Zn smelter soil were leached, and the effects of SOM and clay minerals on HMs leaching were unclear. Herein, the H + consumption and HMs redistribution on SOM and clay minerals were quantitated by the multi-surface model and density functional theory calculations to reveal the roles of SOM and clay minerals in alleviating HMs' leaching. Clay minerals consumed 43.2 %-52.0 % of the exogenous H + , serving as the dominant sink for the exogenous H + due to its high content and hindering H + competitive adsorption on SOM. Protonation of the functional groups constituted >90 % of the total H + captured by clay minerals. Meanwhile, some H + also competed with HMs for adsorption sites on clay minerals due to its 0.497-fold to 1.54-fold higher binding energies than HMs, resulting in the release of HMs. On the contrary, SOM served as an accommodator for taking over the released HMs from clay minerals. The HMs complexation on the low-affinity sites (R-L - ) of SOM was responsible for the recapture of HMs. In Ca-enriched soil, the released HMs were also recaptured by SOM via ion exchange on the R-L-Ca + and the high-affinity sites (R-H-Ca + ) sites due to the 30.8 %-178 % higher binding energies of HMs on these sites than those of Ca. As a result, >63.4 % of the released HMs from clay minerals were transferred to the SOM. Thus, the synergy of SOM and clay minerals in alleviating the leaching of HMs in Pb/Zn smelter soils cannot be ignored in risk assessment and soil remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Owing to the relentless growth of sewage sludge production, achieving low-carbon development in sewage sludge treatment and disposal (STD) is becoming increasingly challenging and unpredictable. However, the STD varied spatially, and city-specific analysis is deemed necessary for sustainable evaluation. Therefore, a lifecycle-based greenhouse gas (GHG), energy, and economic analysis were conducted by considering six local STD alternatives in Wuhan City, China, as a case study. The findings indicated anaerobic digestion combined with digestate utilization for urban greening (ADL) and incineration in existing power plants (INCP) exhibited the least GHG emissions at 34.073 kg CO 2 eq/FU and 644.128 kg CO 2 eq/FU, while INCP generated the most energy at -2594 kW.h/FU. The economic evaluation revealed that ADL and INCP were more beneficial without accounting for land acquisition. Scenario analysis showed that the energy recovery from ADL and INCP is significantly influenced by the hydrolysis yielding rate and sludge organic content. Perturbation sensitivity indicates that regional emission factor of electricity and electricity fee highly influence the overall GHG emission and cost. The results of this study could assist policymakers in identifying viable solutions to the cities experiencing the same sludge treatment burdens., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Recently, increasing attention is given on the resource and energy recovery (e.g. short-chain fatty acids (SCFAs) and phosphorus (P)) from waste active sludge (WAS) under the "Dual carbon goals". This study compared four thiosulfate-assisted Fe 2+ /persulfate (TAFP) pretreatments of WAS, i.e. in-situ TAFP pretreatment (R1), ex-situ TAFP pretreatment (R2), in-situ TAFP pretreatment + pH adjustment (R3) and ex-situ TAFP pretreatment + pH adjustment (R4), followed by anaerobic fermentation over 20 days for SCFA production and P recovery. The results showed that the maximal SCFA yields in R1-4 were 730.2 ± 7.0, 1017.4 ± 13.9, 860.1 ± 40.8, and 1072.0 ± 33.2 mg COD/L, respectively, significantly higher than Control (365.2 ± 17.8 mg COD/L). The findings indicated that TAFP pretreatments (particularly ex-situ TAFP pretreatment) enhanced WAS disintegration and provided more soluble organics and subsequently promoted SCFA production. The P fractionation results showed the non-apatite inorganic P increased from 11.6 ± 0.2 mg P/g TSS in Control to 11.8 ± 0.5 (R1), 12.4 ± 0.3 (R2), 13.2 ± 0.7 (R3) and 12.7 ± 0.7 mg P/g TSS (R4), suggesting TAFP pretreatments improved P bioavailability due to formation of Fe-P mineral (Fe(H 2 PO 4 ) 2 ·2H 2 O), which could be recycled through magnetic separators. These findings were further strengthened by the analysis of microbial community and related marker genes that fermentative bacteria containing SCFA biosynthesis genes (e.g. pyk, pdhA, accA and accB) and iron-reducing bacteria containing iron-related proteins (e.g. feoA and feoB) were enriched in R1-4 (dominant in ex-situ pretreatment systems, R2 and R4). Economic evaluation further verified ex-situ TAFP pretreatment was cost-effective and a better strategy over other operations to treat WAS for SCFA production and P recovery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The complex and rigid floc structure often limits the reutilization of waste activated sludge (WAS). Electrochemical pretreatment (EPT) is one of the most effective technologies that can enhance WAS disintegration. But a comprehensive investigation into how multiple EPT conditions work was rarely reported. The study evaluated the effects of multiple EPT conditions, i.e., different electrolytes (NaCl, Na 2 SO 4 , and CaCl 2 ), electrolytes dosage (0 g/L, 0.5 g/L, 1.0 g/L, and 3.0 g/L), EPT current (0 A, 0.5 A, 1.0 A, and 3.0 A) and EPT time (0 min, 30 min, 60 min, and 90 min) on WAS disintegration. The results showed that NaCl was outstanding from other electrolytes in promoting more WAS disintegration. Besides, a relatively higher NaCl dosage, a higher EPT current, and a longer EPT time promoted more reactive chlorine species (RCS), thus enhancing WAS disintegration in terms of extracellular polymeric substances (EPS) structure destruction and biodegradable organic matter release. After EPT for 60 min at NaCl dosage of 1.0 g/L and current of 1.0 A, the EPS multilayer structure destruction, biodegradable organic matters release, and soluble chemical oxygen demand (SCOD) increase in the supernatant were enhanced by 17.2 %, 130.5 %, and 238.7 %, respectively. Then a predictive quadratic model was established and the impact significance of the above EPT factors for enhancing WAS disintegration followed dosage of NaCl > current > EPT time. Furthermore, response surface methodology (RSM) suggested NaCl dosage of 2.75 g/L, current of 2.0 A, and EPT time of 30 min were the optimal EPT conditions, bringing a 42.0 % increase in the net economic benefit of WAS treatment compared to without EPT., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Food waste (FW) is a primary constituent of solid waste and its adequate management is a global challenge. Instead of disposal in landfills, integrated treatment of FW with wastewater (WW) can diminish both environmental and economic burdens. Utilizing steady-state modelling and life cycle assessment techniques, this study investigated the prospects of FW integration with biological WW treatment in terms of WW treatment performance, net energy and carbon footprint and economics of the process. The explored scenarios include co-disposal and treatment with WW by using FW disposers and anaerobic co-digestion with sewage sludge in Hong Kong. Compared to the existing WW and FW treatment, the integrated scenarios significantly improved the energy balance (~83-126%), net greenhouse gas emissions (~90%), and economics of operation, with permissible impact on WW treatment performance. Therefore, utilizing the surplus capacity of the existing WW treatment facilities, these integrated scenarios are a promising solution for sustainable development., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Decentralized wastewater treatment in rural areas is an imperative challenge around the world, particularly in developing countries. The composite filter bed reactor is viable for decentralized wastewater treatment, but its performance on nitrogen removal often fluctuates with the unstable influent characteristics and loadings. Here, a composite filter bed reactor integrating sulfur, iron(II), and fixed organic carbon (shaddock peel) was developed and continuously operated under different conditions. The fixed organic carbon source promoted nitrogen removal with an efficiency higher than 90% and reduced effluent sulfate level by 40%, indicating that the integrated electron donors could improve the resistance and stability of the reactor. Moreover, sulfur-oxidizing bacteria (Thiomonas, Sulfuriferula, and Acidithiobacillus), iron-oxidizing bacteria (Ferritrophicum), and denitrifiers (Simplicispira and Hydrogenophaga) were identified in the anoxic/anaerobic layer of the reactor, suggesting that mixotrophic denitrification was stimulated by sulfur, iron(II), and fixed organic carbon. The findings of this study indicate that the developed reactor with the integrated electron donors could be reliable for carbon, nitrogen, and phosphorus removal and promising for the application of decentralized wastewater treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Eutrophication promotes massive cyanobacteria blooms (CBBs), leading to the release of volatile organic compounds (VOCs). To investigate the effects of cyanobacteria on VOC emissions, field campaigns were carried out in eutrophic Chaohu Lake at six sites with different microalgae densities during CBBs in summer 2019, and incubation experiments were performed in the laboratory. The results showed that the lake water was the primary source of VOCs at six sampling sites in Chaohu Lake during CBBs, with an average total VOC flux of 81.2 ± 20.6 μg m -2 h -1 . Alkanes were the most abundantly emitted VOCs, with a share of 23.1-63.7% of total emitted VOCs, followed by aromatics (16.6-46.3%). The fluxes of total VOCs were significantly greater at sites B and/or C than at site A in July, and at site B' and/or C' than at site A' in August in Chaohu Lake. The fluxes of total VOCs from living and decayed cyanobacteria in the experimental treatments were two orders of magnitude higher than the corresponding values in the control treatments in the laboratory incubation. Taken together, these results suggested that CBBs potentially enhanced VOC emissions from the eutrophic lake, and that cyanobacteria acted as an important source of VOCs. Additionally, non-methane hydrocarbons (i.e., alkanes, alkenes, and aromatics) predominated among the released VOCs during the stabilization and senescence stages, while oxygenated volatile organic compounds (i.e. alcohols, aldehydes, ketones, esters, and furans) prevailed during the apoptosis stage and aromatics and volatile organic sulfur compounds predominated during the decomposition stage, suggesting that VOC emissions varied markedly at different life stages., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Sulfite pretreatment is effective for enhancing the biodegradability of waste activated sludge (WAS). However, the mixture of primary sludge (PS) and WAS is normally collected and treated together, and the effect of sulfite on the sludge mixture remains unclear. Here, we reported that sulfite pretreatment could disintegrate the flocs of the sludge mixture and improve sludge biodegradability. The substrate release from the sludge mixture after sulfite pretreatment (100, 300, and 500 mg SO 3 2- -S/L) could be enhanced with soluble chemical oxygen demand by up to 1.58 times, soluble nitrogen by up to 1.38 times, soluble polysaccharides by up to 3.04 times and proteins by up to 6.08 times. Further analysis on flocs structure suggests that sulfite may destruct the functional groups of proteins and amino acids and lyse the main structure of sludge cell walls. Moreover, methane production from the sludge mixture could be enhanced by 16% after pretreated by sulfite at 500 mg S/L (i.e., 123.59 CH 4 /kg VS added ), whereas the digested sludge volume could be reduced by 1.51 times. Environmental implications suggest that sulfite pretreatment could save sludge treatment costs by 1.06 $/PE/y and reduce CO 2 -equivalent emissions by 5.19 kg CO 2 /PE/y, demonstrating its potential as a cost-effective and carbon-neutral technology for sludge management., Competing Interests: Declaration of competing interest The authors declare that they have no competing financial interests or personal relationships that can appear to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Patients on dialysis have a high burden of bone-related comorbidities, including fractures. We report a post hoc analysis of the prospective cohort study HDF, Hearts and Heights (3H) to determine the prevalence and risk factors for chronic kidney disease-related bone disease in children on hemodiafiltration (HDF) and conventional hemodialysis (HD)., Methods: The baseline cross-sectional analysis included 144 children, of which 103 (61 HD, 42 HDF) completed 12-month follow-up. Circulating biomarkers of bone formation and resorption, inflammatory markers, fibroblast growth factor-23, and klotho were measured., Results: Inflammatory markers interleukin-6, tumor necrosis factor-α, and high-sensitivity C-reactive protein were lower in HDF than in HD cohorts at baseline and at 12 months ( P  < .001). Concentrations of bone formation (bone-specific alkaline phosphatase) and resorption (tartrate-resistant acid phosphatase 5b) markers were comparable between cohorts at baseline, but after 12-months the bone-specific alkaline phosphatase/tartrate-resistant acid phosphatase 5b ratio increased in HDF ( P  = .004) and was unchanged in HD ( P  = .44). On adjusted analysis, the bone-specific alkaline phosphatase/tartrate-resistant acid phosphatase 5b ratio was 2.66-fold lower (95% confidence interval, -3.91 to -1.41; P  < .0001) in HD compared with HDF. Fibroblast growth factor-23 was comparable between groups at baseline ( P  = .52) but increased in HD ( P  < .0001) and remained unchanged in HDF ( P  = .34) at 12 months. Klotho levels were similar between groups and unchanged during follow-up. The fibroblast growth factor-23/klotho ratio was 3.86-fold higher (95% confidence interval, 2.15-6.93; P  < .0001) after 12 months of HD compared with HDF., Conclusion: Children on HDF have an attenuated inflammatory profile, increased bone formation, and lower fibroblast growth factor-23/klotho ratios compared with those on HD. Long-term studies are required to determine the effects of an improved bone biomarker profile on fracture risk and cardiovascular health., (© 2021 International Society of Nephrology. Published by Elsevier Inc.)

The existence of abundant biofilms on sewer pipeline walls can lead to negative environmental impacts, such as poisonous gas release and pipe corrosions through transforming various pollutants. Investigating the formation process of sewer biofilms is of importance in advancing knowledge of sewer operation and maintenance. In this study, the changes in physical characteristics, microstructure, and microbial communities of sewer biofilm were analyzed in-depth in a pilot-scale gravity sewer during a 45-day operation. The results show that a high specific surface area at the early stage could channel the substrates for stimulating the primary colonizers (e.g., Cytophagia, Sphingobacteriia, Alpha-, and Betaproteobacteria), which could excrete an extracellular matrix to facilitate biofilm growth. The sewer biofilms were gradually formed with 62 g VS/m 2 organic content, 1.2 mm biofilm thickness, and 89 mg/cm 3 dry density after 45 days operation. Moreover, the biofilm growth promoted the emergence of facultative bacteria and anaerobes (affiliated with Flavobacteriia, Gemmatimonadetes, Deltaproteobacteria, and Epsilonproteobacteria). Microelectrode analysis further verified that an anaerobic zone existed in mature biofilm with a negative oxidation-reduction potential (-105 mV), where approximately 0.1 μmol/L of sulfide was produced. Our results suggest that the migration of the microbial community correlated with the changes in the evolved physical characteristics and microstructure of sewer biofilm, and this can contribute to the strategies for sulfide control for improving sewer maintenance., (Copyright © 2021 Elsevier Inc. All rights reserved.)

A magnetic-pH dual responsive drug delivery system was prepared for antibacterial therapy to reduce the side effects on nonpathological cells or tissues. Iron oxide (Fe 3 O 4 ) core was surface-functionalized with silane coupling agents to link β‑cyclodextrin (β-CD) (CDMNP), and a polypseudorotaxanes shell where polyethyleneglycol chains threaded much CD molecules was further prepared on the magnetic Fe 3 O 4 core (CDMNP-PEG-CD) to enhance loading capacity of roxithromycin (ROX). CDMNP-PEG-CD with a hydrodynamic diameter of ~168 nm was cytocompatible, superparamagnetic, magnetic-responsive and stable for 180 min of storage. No significant interaction with serum albumin was shown for the nanocomposites. The in vitro release from ROX-loaded CDMNP-PEG-CD nanocomposites was about 76% of total drug within 30 min at pH 1.0, 1.6-fold of that at pH 7.4 and 2-fold of that at pH 8.0, presenting pH-responsive drug release behaviors. The nanocomposites showed positive antibacterial activity against both E. coli and S. aureus based on an agar diffusion method. The antibacterial activity of the nanocomposites was more sensitive against E. coli than S. aureus, and the inhibition halo against E. coli was 85% more than that of Fe 3 O 4 . CDMNP-PEG-CD nanocomposites allowed for the localization and fast concentration of hydrophobic drugs, providing a broad potential range of therapeutic applications., (Copyright © 2019. Published by Elsevier B.V.)