Autotrophic denitrification based on sulfur-iron minerals: advanced wastewater treatment technology with simultaneous nitrogen and phosphorus removal.

Autotrophic denitrification technology has many advantages, including no external carbon source addition, low sludge production, high operating cost efficiency, prevention of secondary sewage pollution, and stable treatment efficiency. At present, the main research on autotrophic denitrification electron donors mainly includes sulfur, iron, and hydrogen. In these autotrophic denitrification systems, pyrite has received attention due to its advantages of easy availability of raw materials, low cost, and pH stability. When pyrite is used as a substrate for autotropic denitrification, sulfide (S2-) and ferrous ion (Fe2+) in the substrate will provide electrons to convert nitrate (NO3-) in sewage first to nitrite (NO2-), then to nitrogen (N2), and finally to discharge the system. At the same time, sulfide (S2-) loses electrons to sulfate (SO42-) and ferrous ion (Fe2+) loses electrons to ferric iron (Fe3+). Phosphates (PO43-) in wastewater are chemically combined with ferric iron (Fe3+) to form ferric phosphate (FePO4) precipitate. This paper aims to provide a detailed and comprehensive overview of the dynamic changes of nitrogen (N), phosphorus (P), and other substances in the process of sulfur autotrophic denitrification using iron sulfide, and to summarize the factors that affect wastewater treatment in the system. This work will provide a relevant research direction and theoretical basis for the field of sulfur autotrophic denitrification, especially for the related experiments of the reaction conversion of various substances in the system.

Guar gum-enhanced emission of gold nanoclusters for α-glucosidase activity detection and anti-diabetic agents screening in plant extracts.

The development of efficient fluorescent methods for α-glucosidase (α-Glu) detection and α-Glu inhibitor screening plays a critical role in the therapy of type 2 diabetes (T2D). Herein, guar gum (GG), a high-abundant and non-toxic natural polymer originated from the seeds of a drought-tolerant plant, Cyamposis tetragonolobus, was found to be able to enhance the fluorescence emission of gold nanoclusters (AuNCs) probe. The emission enhancement effect was achieved by using GG at very low concentrations (<1.0 wt%) and presented in a viscosity-dependent manner through increasing solvent reorientation time and inhibiting intramolecular motions of AuNCs. Furthermore, the enhanced emission of the AuNCs was quenched by Fe3+via dynamic quenching and then restored by α-Glu. Accordingly, a fluorimetric method was proposed for the determination of α-Glu. Owing to the fluorescence enhancement effect of GG on the AuNCs probe, the detection limit of the approach was 0.13 U L-1 and the detection range was up to 5 orders of magnitude from 0.2 to 4000 U L-1, which was much better than most current α-Glu detection methods. The approach was further applied to α-Glu inhibitors screening from natural plant extracts, providing great prospects for the prevention and treatment of T2D.

Treatment of high-phosphorus load wastewater by column packed with non-burning compound filler/gravel/ceramsite: evaluation of performance and microorganism community.

Cost-effective and environmental-friendly substrates are essential for the constructed wetlands (CWs). In this study, the column test was used to explore the differences in pollutant purification performance, microbial community structure and abundance between non-burning compound filler and conventional CWs substrates (i.e. gravel and ceramsite) at low temperature (0-15℃). It was found that the maximum phosphorus removal efficiency of compound filler (99%) was better than gravel (18%) and ceramsite (21%). Besides, the proportion of aerobic heterotrophic bacteria capable of ammonium oxidation, nitrification and denitrification (i.e. Pseudomonas, Acinetobacter, and Acetoanaerobium) was enhanced by compound filler, which has an excellent potential for nitrogen removal in the subsequent purification process. These results demonstrated that the self-made non-burning compound filler was a potential substrate for CWs, which was of great significance for the resource utilization of solid wastes such as polyaluminum chloride residue.

Aesculetin Inhibits Proliferation and Induces Mitochondrial Apoptosis in Bladder Cancer Cells by Suppressing the MEK/ERK Signaling Pathway.

BACKGROUND: Aesculetin (AE), a natural coumarin derivative found in traditional medicinal herbs, has a variety of pharmacological effects. However, the role of AE and its molecular mechanisms of action on bladder cancer remains undefined. OBJECTIVE: The study aims to explore the anti-tumor effects of AE on bladder cancer cells and the associated molecular mechanisms. METHODS: We performed a Cell Counting Kit-8 assay to examine the inhibitory effects of AE on 5637 and T24 cells. The anti-tumor effects of AE on 5637 cells were evaluated by performing colony formation, living/dead cell staining, apoptosis, cell cycle, migration and invasion assays. The expression levels of related proteins were determined using western blotting. RESULTS: The viability of 5637 and T24 cells was decreased by AE. AE significantly inhibited colony formation, arrested the cell cycle at the G0/G1 phase, decreased migration and invasion, decreased the mitochondrial membrane potential and increased apoptosis in 5637 cells. Western blotting results showed the release of cytochrome C from mitochondria; the activation of caspase-9 and caspase-3; decrease in CDK4, CCND1, MMP2 and MMP9 levels and an increase in the BAX/BCL-2 protein ratio after treatment with AE. AE also downregulated the levels of p-ERK and p- MEK proteins. Pre-treatment with U0126 significantly enhanced the anti-tumor effects of AE. CONCLUSIONS: AE inhibited the proliferation and induced the apoptosis of bladder cancer cells through the MEK/ERK pathway. These findings provide possible therapeutic strategies for bladder cancer.

Occurrence of Perfluoroalkyl and Polyfluoroalkyl Substances in Ice Cream, Instant Noodles, and Bubble Tea.

Food consumption is a significant exposure route to perfluoroalkyl and polyfluoroalkyl substances (PFAS). The concentrations of 27 PFAS in fast food were determined by ultrahigh-performance liquid chromatography-high resolution mass spectrometry. In ice cream, instant noodles, and bubble tea, some PFAS were detected, among which perfluorooctanoic acid, perfluoro-n-butanoic acid, and 6:2 polyfluoroalkyl phosphate monoester showed relatively high concentrations. PFAS migrating from bubble tea cups to the food simulant of 50% ethanol aqueous solution showed a difference compared with those migrating into bubble tea matrices. The migration of 27 PFAS to bubble tea samples indicated that long storage time increased PFAS levels (up to 4.8 times) and so did high storage temperature (up to 7.3 times). The hazard ratio, defined as the ratio of the estimated daily intake and the reference dose, was calculated, and it suggests that the total PFAS exposure risk due to consumption of bubble tea should be of concern.

Construction of a copper nanocluster/MnO2 nanosheet-based fluorescent platform for butyrylcholinesterase activity detection and anti-Alzheimer's drug screening.

An abnormal level of butyrylcholinesterase (BChE) activity is highly connected with hepatic damage and Alzheimer's disease. Herein, a facile and efficient method was proposed for BChE detection by incorporating polyethyleneimine-capped copper nanoclusters (PEI-CuNCs) with manganese dioxide (MnO2) nanosheets. The emission of PEI-CuNCs can be significantly quenched by MnO2 nanosheets via the inner filter effect. With the addition of BChE, the hydrolysis of butyrylthiocholine iodide produces thiocholine which can reduce MnO2 nanosheets to Mn2+, thus resulting in the fluorescence recovery of PEI-CuNCs. Based on that, a fluorescence "turn-on" sensing platform for BChE activity determination was constructed with a detection limit of 2.26 U L-1. This sensing method is able to detect BChE in human serum samples and identify the serums of normal persons and cirrhotic patients effectively, indicating its great potential in the clinical diagnosis of liver diseases. Furthermore, the approach can also be used to screen BChE inhibitors, which are promising medications to alleviate the symptoms of Alzheimer's disease.

Preparation of a novel non-burning polyaluminum chloride residue(PACR) compound filler and its phosphate removal mechanisms.

As an inevitable industrial by-product, polyaluminum chloride residue (PACR) will cause serious harm to the environment if directly buried and dumped. The aim of this paper was searched a new economical, environmental, and practical way of utilization for PACR. In this paper, a novel non-burning PACR compound filler was made from mainly PACR. The prepared compound filler has excellent physical properties and phosphate adsorption efficiency of up to 99.9%. Static adsorption experiments showed that the adsorption process of phosphorus by the compound filler conformed to the pseudo-second-order kinetic model and intra-particle diffusion model. Langmuir and Freundlich isotherm models described the phosphorus adsorption process well, and the maximum phosphate adsorption capacity arrived at 42.55 mg/g. The phosphate adsorption by the compound filler is a spontaneous endothermic process. The main mechanisms are ligand exchange and Lewis acid-base interactions; calcium and aluminum play important roles in the adsorption of phosphorus by the compound filler. Dynamic column experiments showed that as much as 90% of the phosphorus removal by compound filler, and the phosphorus concentration decreased from 1 to ~0.1mg/L. The results provide a new waste resource utilization method for PACR and show the good application potential of prepared compound filler in constructed wetlands.

Confining copper nanoclusters on exfoliation-free 2D boehmite nanosheets: Fabrication of ultra-sensitive sensing platform for α-glucosidase activity monitoring and natural anti-diabetes drug screening.

α-Glucosidase (α-Glu) and its inhibitors play critical roles in diabetes therapy. Herein, a simple and ultra-sensitive fluorescence sensing approach was fabricated for α-Glu activity monitoring and natural inhibitor screening by electrostatically confining negatively charged glutathione-capped copper nanoclusters (GSH-CuNCs) on exfoliation-free and positively charged 2D boehmite (Boe) nanosheets. Boe significantly improved the fluorescence emission/stability of GSH-CuNCs and simultaneously led to an obvious blue-shift of the excitation peak of CuNCs from 365 nm to 330 nm. As a result, the fluorescence emission of Boe@GSH-CuNCs was efficiently quenched by 4-nitrophenyl-α-D-glucopyranoside (PNPG) with a maximum absorbance peak (λmax) at 310 nm via inner filter effect, and sequentially recovered by α-Glu through the hydrolysis of PNPG to p-nitrophenol (λmax = 410 nm). Accordingly, an ultra-sensitive fluorescence assay for the determination of α-Glu activity was proposed by using Boe@GSH-CuNCs as fluorescence probes. The detection limit of 0.43 U/L was achieved, which was lower than most of other α-Glu activity assays. Furthermore, this method was capable of screening α-Glu inhibitors originated from actinomycetes, peanut, sophora flower, celery, and orange as potential anti-diabetes drugs. Taken together, this work provided a promising strategy for clinical treatment of diabetes and discovery of anti-diabetes drugs.

Differential behaviors of silver nanoparticles and silver ions towards cysteine: Bioremediation and toxicity to Phanerochaete chrysosporium.

Potential transformations of silver nanoparticles (AgNPs) upon interaction with naturally ubiquitous organic ligands in aquatic environments influence their transport, persistence, bioavailability, and subsequent toxicity to organisms. In this study, differential behaviors of AgNPs and silver ions (Ag+) towards cysteine (Cys), an amino acid representative of thiol ligands that easily coordinate to Ag+ and graft to nanoparticle surfaces, were investigated in the aspects of bioremediation and their toxicity to Phanerochaete chrysosporium. Total Ag removal, 2,4-dichlorophenol (2,4-DCP) degradation, extracellular protein secretion, and cellular viability were enhanced to some extent after supplement of various concentrations of cysteine under stress of AgNPs and Ag+. However, an obvious decrease in total Ag uptake was observed after 5-50 µM cysteine addition in the groups treated with 10 µM AgNPs and 1 µM Ag+, especially at a Cys:Ag molar ratio of 5. More stabilization in uptake pattern at this ratio was detected under Ag+ exposure than that under AgNP exposure. Furthermore, in the absence of cysteine, all Ag+ treatments stimulated the generation of reactive oxygen species (ROS) more significantly than high-dose AgNPs did. However, cysteine supply under AgNP/Ag+ stress aggravated ROS levels, albeit alleviated at 100 µM Ag+, indicating that the toxicity profiles of AgNPs and Ag+ to P. chrysosporium could be exacerbated or marginally mitigated by cysteine. The results obtained were possibly associated with the lability and bioavailability of AgNP/Ag+-cysteine complexes.

Effect of Chaiqinchengqi decoction on serum amyloid A in severe acute pancreatitis patients.

OBJECTIVE: To investigate the effect of Chaiqinchengqi decoction (CQCQD) on serum amyloid A (SAA) in severe acute pancreatitis (SAP) patients. METHODS: Thirty-five participants enrolled and were randomly assigned into either a treatment condition (n = 17, treated with CQCQD) or a control condition (n = 18, treated with placebo) 24 hours following the onset of the disease. No statistical difference was observed in either group at baseline. Upon admission, the Acute Physiology and Chronic Health Evaluation score II (APACHE II), SAA, serum C-reactive protein (CRP) and interleukin-6 (IL-6) were measured, as well as on the first, 3rd and 7th day and were compared between the two groups. Organ complications, infection, operation rate, mortality and hospital stay were also compared. RESULTS: The duration of acute respiratory distress syndrome, acute hepatitis, acute renal failure, gastrointestinal failure and blood coagulation dysfunction were shorter in the treatment group than in those in the control group (P < 0.05). The secondary infection rates and the hospital fees in the treatment group were lower than those in the control group (P < 0.05) as well as length of hospital stay (P < 0.01). After 3 days of hospitalization, the APACHEII, score SAA levels, serum CRP and IL-6 in the treatment group was lower than those in the control group (P < 0.05). SAA was positively correlated with serum CRP (R = 0.346, P = 0.042), Ranson score (R = 0.442, P = 0.008) and serum IL-6 (R = 0.359, P = 0.034). The area under the receiver operating characteristic curve of admission SAA predict pancreatic necrosis (PN) was 0.815 (95% CI: 0.625-0.954; P = 0.006). The best cut-off value of admission SAA was 7.85 mg/L with the sensitivity 84.6% and specificity 68.2%. CONCLUSIONS: The CQCQD can reduce the duration of organ damage through lowering the SAA in SAP patients and the SAA can early predict the PN and severity of SAP patients.