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1.
Environ Sci Technol ; 58(10): 4792-4801, 2024 Mar 12.
Article in English | MEDLINE | ID: mdl-38427382

ABSTRACT

N-Nitrosamines are potential human carcinogens frequently detected in natural and engineered aquatic systems. This study sheds light on the role of carbonyl compounds in the formation of N-nitrosamines by nitrosation of five secondary amines via different pathways. The results showed that compared to a control system, the presence of formaldehyde enhances the formation of N-nitrosamines by a factor of 5-152 at pH 7, depending on the structure of the secondary amines. Acetaldehyde showed a slight enhancement effect on N-nitrosamine formation, while acetone and benzaldehyde did not promote nitrosation reactions. For neutral and basic conditions, the iminium ion was the dominant intermediate for N-nitrosamine formation, while carbinolamine became the major contributor under acidic conditions. Negative free energy changes (<-19 kcal mol-1) and relatively low activation energies (<18 kcal mol-1) of the reactions of secondary amines with N2O3, iminium ions with nitrite and carbinolamines with N2O3 from quantum chemical computations further support the proposed reaction pathways. This highlights the roles of the iminium ion and carbinolamine in the formation of N-nitrosamines during nitrosation in the presence of carbonyl compounds, especially in the context of industrial wastewater.


Subject(s)
Nitrosamines , Humans , Nitrosamines/chemistry , Nitrosation , Amines , Carcinogens , Nitrites/chemistry
2.
Medicine (Baltimore) ; 103(10): e37446, 2024 Mar 08.
Article in English | MEDLINE | ID: mdl-38457547

ABSTRACT

RATIONALE: Compound heterozygotes for deletional ß-thalassemia can be difficult to diagnose due to its diverse clinical presentations and no routine screenings. This can lead to disease progression and delay in treatment. PATIENT CONCERNS: We reported pedigree analysis and genetic research in a family with rare ß-thalassemia. DIAGNOSIS: Pedigree analysis and genetic research demonstrated that the patient was a compound heterozygote for ß-thalassemia CD17/Southeast Asian hereditary persistence of fetal hemoglobin deletion, inherited from the parents. Magnetic resonance imaging T2* examination revealed severe iron deposition in the liver. Echocardiography revealed endocardial cushion defect. INTERVENTIONS: The patient was treated with Deferasirox after receiving the final molecular genetic diagnosis. The initial once-daily dose of Deferasirox was 20 mg/kg/d. OUTCOMES: The patient discontinued the medication three months after the first visit. Two years later, the patient visited the Department of Hepatobiliary and Pancreatic Diseases. He was recommended to undergo splenectomy after surgical repair of the congenital heart disease. However, the patient refused surgical treatment because of the economic burden. LESSONS: We report that fetal hemoglobin is a sensitive indicator for screening large deletions of the ß-globin gene, which can be effectively confirmed by the multiplex ligation-dependent probe amplification assay. In non-transfusion-dependent thalassemia patients, iron status assessment should be regularly performed, and iron chelation treatment should be initiated early. This case will provide insights for the diagnosis of rare genotypes of ß-thalassemia and has important implications for genetic counseling.


Subject(s)
beta-Thalassemia , Male , Humans , beta-Thalassemia/genetics , beta-Thalassemia/diagnosis , Fetal Hemoglobin/genetics , Pedigree , Deferasirox , Southeast Asian People , Genetic Research , China , Iron , Heterozygote
3.
Environ Res ; 249: 118361, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38325776

ABSTRACT

Bismuth-iron semiconductor materials have been widely studied in the photocatalytic field due to their excellent light responsiveness. Among them, the potential and mechanism regarding photocatalytic degradation of organic pollutants by Bi2Fe4O9 are seriously ignored. In this research, Bi2Fe4O9/reduced graphene oxide (BFO/rGO) was successfully synthesized for tetracycline (TC) removal. Under visible light irradiation, the TC degradation efficiency reached 83.73% within 60 min, which was much higher than that of pure BFO or rGO. The impacts of crucial factors (TC initial concentration, humic acid concentration, pH value and inorganic anions) were systematically analyzed. The photoelectric performance experiments indicated that the addition of rGO decreased the electron-hole pair recombination efficiency and improved the charge transfer efficiency, thus significantly enhancing the photocatalytic performance. According to quenching experiments and EPR (Electron Paramagnetic Resonance) analysis, superoxide radical (•O2-) and hole (h+) were determined as the main active species during degradation reactions. Eventually, the possible degradation routes of TC were presented by identifying intermediates.


Subject(s)
Bismuth , Graphite , Light , Nanocomposites , Tetracycline , Tetracycline/chemistry , Graphite/chemistry , Bismuth/chemistry , Nanocomposites/chemistry , Catalysis , Water Pollutants, Chemical/chemistry
4.
Proc Natl Acad Sci U S A ; 121(3): e2300582121, 2024 Jan 16.
Article in English | MEDLINE | ID: mdl-38190543

ABSTRACT

Plastics are now omnipresent in our daily lives. The existence of microplastics (1 µm to 5 mm in length) and possibly even nanoplastics (<1 µm) has recently raised health concerns. In particular, nanoplastics are believed to be more toxic since their smaller size renders them much more amenable, compared to microplastics, to enter the human body. However, detecting nanoplastics imposes tremendous analytical challenges on both the nano-level sensitivity and the plastic-identifying specificity, leading to a knowledge gap in this mysterious nanoworld surrounding us. To address these challenges, we developed a hyperspectral stimulated Raman scattering (SRS) imaging platform with an automated plastic identification algorithm that allows micro-nano plastic analysis at the single-particle level with high chemical specificity and throughput. We first validated the sensitivity enhancement of the narrow band of SRS to enable high-speed single nanoplastic detection below 100 nm. We then devised a data-driven spectral matching algorithm to address spectral identification challenges imposed by sensitive narrow-band hyperspectral imaging and achieve robust determination of common plastic polymers. With the established technique, we studied the micro-nano plastics from bottled water as a model system. We successfully detected and identified nanoplastics from major plastic types. Micro-nano plastics concentrations were estimated to be about 2.4 ± 1.3 × 105 particles per liter of bottled water, about 90% of which are nanoplastics. This is orders of magnitude more than the microplastic abundance reported previously in bottled water. High-throughput single-particle counting revealed extraordinary particle heterogeneity and nonorthogonality between plastic composition and morphologies; the resulting multidimensional profiling sheds light on the science of nanoplastics.


Subject(s)
Drinking Water , Microscopy , Humans , Microplastics , Plastics , Algorithms
5.
Environ Pollut ; 345: 123441, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38272162

ABSTRACT

Nanoplastics (NPs) have become common worldwide and attracted increasing attention due to their serious toxic effects. Owing to their higher surface area and volume ratios and ability to easily enter tissues, NPs impose more serious toxic effects than microplastics. However, the effect of NP exposure on vascular stenosis remains unclear. To measure the effects of polystyrene NP (PS-NP) exposure on vascular toxicity, we conducted analyses of blood biochemical parameters, pathological histology, high-throughput sequencing, and bioinformatics. Red fluorescent PS-NPs (100 nm) were effectively uptake by mouse vascular arterial tissue. The uptake of PS-NPs resulted in vascular toxicity, including alterations in lipid metabolism and thickening of the arterial wall. Based on PIWI-interacting RNA (piRNA) sequencing, 1547 and 132 differentially expressed piRNAs (DEpiRNAs) were detected in the PS-NP treatment group after 180 and 30 days, including 787 and 86 upregulated and 760 and 46 downregulated compared with the control group, respectively. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses indicated that the target genes of DEpiRNAs were mostly involved in cell growth and cell motility-related signaling, such as the MAPK signaling pathway. This is the first study to highlight the alteration in piRNA levels in mouse vascular arterial tissue after PS-NP exposure. This study adds to the knowledge regarding the regulatory mechanism of pathological changes induced by PS-NP exposure.


Subject(s)
Nanoparticles , Water Pollutants, Chemical , Animals , Mice , Piwi-Interacting RNA , Constriction, Pathologic , Microplastics , Polystyrenes/toxicity , Plastics
6.
Sci Total Environ ; 912: 169515, 2024 Feb 20.
Article in English | MEDLINE | ID: mdl-38154651

ABSTRACT

Nanoplastics pose several health hazards, especially vascular toxicity. Transfer RNA-derived small RNAs (tsRNAs) are novel noncoding RNAs associated with different pathological processes. However, their biological roles and mechanisms in aberrant vascular smooth muscle cell (VSMC) plasticity and vascular injury are unclear. This study investigated the potent effects of tsRNAs on vascular injury induced by short- and long-term exposure to polystyrene nanoplastics (PS-NPs). Mice were exposed to PS-NPs (100 nm) at different doses (10-100 µg/mL) for 30 or 180 days. High-throughput sequencing was used to analyze tsRNA expression patterns in arterial tissues obtained from an in vivo model. Additionally, quantitative real-time polymerase chain reaction, fluorescent in situ hybridization assays, and dual-luciferase reporter assays were performed to measure the expression and impact of tiRNA-Glu-CTC on VSMCs exposed to PS-NPs. Short-term (≥50 µg/mL, moderate concentration) and long-term (≥10 µg/mL, low concentration) PS-NP exposure induced vascular injury in vivo. Cellular experiments showed that the moderate concentration of PS-NPs induced VSMC phenotypic switching, whereas a high concentration of PS-NPs (100 µg/mL) promoted VSMC apoptosis. PS-NP induced severe mitochondrial damage in VSMCs, including overexpression of reactive oxygen species, accumulation of mutated mtDNA, and dysregulation of genes related to mitochondrial synthesis and division. Compared with the control group, 13 upregulated and 12 downregulated tRNA-derived stress-induced RNAs (tiRNAs) were observed in the long-term PS-NP (50 µg/mL) exposure group. Bioinformatics analysis indicated that differentially expressed tiRNAs targeted genes that were involved in vascular smooth muscle contraction and calcium signaling pathways. Interestingly, tiRNA-Glu-CTC was overexpressed in vivo and in vitro following PS-NP exposure. Functionally, the tiRNA-Glu-CTC inhibitor mitigated VSMC phenotypic switching and mitochondrial damage induced by PS-NP exposure, whereas tiRNA-Glu-CTC mimics had the opposite effect. Mechanistically, tiRNA-Glu-CTC mimics induced VSMC phenotypic switching by downregulating Cacna1f expression. PS-NP exposure promoted VSMC phenotypic switching and vascular injury by targeting the tiRNA-Glu-CTC/Cacna1f axis.


Subject(s)
Vascular System Injuries , Mice , Animals , Vascular System Injuries/genetics , Vascular System Injuries/metabolism , Vascular System Injuries/pathology , Muscle, Smooth, Vascular/metabolism , Microplastics/metabolism , In Situ Hybridization, Fluorescence , Cell Proliferation , RNA/metabolism , Cells, Cultured
7.
J Pharm Pharmacol ; 75(8): 1086-1099, 2023 Aug 01.
Article in English | MEDLINE | ID: mdl-37167529

ABSTRACT

OBJECTIVES: We aimed to elucidate the therapeutic potential of Chrysin (CN) against the high-fat diet (HFD) induced non-alcoholic fatty liver disease (NAFLD) and its mechanism. METHODS: To assess the hypothesis, NAFLD was induced in C57BL/6 mice by feeding a high-fat diet for up to two months, followed by CN administration (for three months). Liver injury/toxicity, lipid deposition, inflammation and fibrosis were detected via molecular and biochemical analysis, including blood chemistry, immunoimaging and immunoblotting. Moreover, we performed proteomic analysis to illuminate Chrysin's therapeutic effects further. KEY FINDINGS: CN treatment significantly reduced liver-fat accumulation and inflammation, ultimately improving obesity and liver injury in NAFLD mice. Proteomic analysis showed that CN modified the protein expression profiles in the liver, particularly improving the expression of proteins related to energy, metabolism and inflammation. Mechanistically, CN treatment increased AMP-activated protein and phosphorylated CoA (P-ACC). Concurrently, it reduced inflammation and inflammation activation by inhibiting NLRP3 expression. CONCLUSIONS: In summary, CN treatment reduced lipid metabolism by AMPK and inflammasome activation by NLRP3 inhibition, ultimately improving NAFLD progression. These findings suggest that CN could be a potential treatment candidate for the NFLAD condition.


Subject(s)
Non-alcoholic Fatty Liver Disease , Mice , Animals , Non-alcoholic Fatty Liver Disease/drug therapy , Non-alcoholic Fatty Liver Disease/prevention & control , AMP-Activated Protein Kinases/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , Proteomics , Mice, Inbred C57BL , Liver , Inflammation/drug therapy , Inflammation/metabolism , Lipid Metabolism , Diet, High-Fat/adverse effects
8.
Environ Pollut ; 329: 121645, 2023 Jul 15.
Article in English | MEDLINE | ID: mdl-37088256

ABSTRACT

Selective constructing of heterojunctions enables directional electron-hole migration and favorable charge separation. In this study, a novel p-n junction Bi3.64Mo0.36O6.55 (BMO) nanoparticles anchored in BiOI construct by hydrothermal and subsequent in-situ synthesis. The construction of tight heterojunctions that enhance the characteristic absorption of visible light by Bi3.64Mo0.36O6.55/BiOI (BIMO) and expose more reactive sites can be used to facilitate the rapid degradation of antibiotics (Tetracycline, TC), endocrine disruptors (Bisphenol A, BPA) and dyes in water. In addition, the BIMO catalyst maintained the rapid degradation rate of TC despite the interference of inorganic anions and aqueous substrates. The charge transfer pathways and radical species between the heterojunction components were investigated. In addition, the intermediates and toxicological analysis showed that TC was further mineralized and the small molecule products were generated significantly less toxic and less contaminated. In conclusion, this study synthesized photocatalysts based on p-n heterojunctions, which have potential applications for the degradation of TC.


Subject(s)
Nanoparticles , Water Purification , Anti-Bacterial Agents , Coloring Agents , Electrons , Water
9.
J Hazard Mater ; 450: 131089, 2023 05 15.
Article in English | MEDLINE | ID: mdl-36870096

ABSTRACT

Micro-nanoplastics (M-NPs) have become an emerging critical issue in the environment because they migrate easily, can bioaccumulate with toxic effects, and are difficult to degrade. Unfortunately, the current technologies for removing or degrading M-NPs in drinking water are insufficient to eliminate them completely, and residual M-NPs in drinking water may pose a threat to human health by impairing human immunity and metabolism. In addition to their intrinsic toxic effects, M-NPs may be even more harmful after drinking water disinfection than before disinfection. Herein, this paper comprehensively summarizes the negative impacts of several commonly used disinfection processes (ozone, chlorine, and UV) on M-NPs. Moreover, the potential leaching of dissolved organics from M-NPs and the production of disinfection byproducts during the disinfection process are discussed in detail. Moreover, due to the diversity and complexity of M-NPs, their adverse effects may exceed those of conventional organics (e.g., antibiotics, pharmaceuticals, and algae) after the disinfection process. Finally, we propose enhanced conventional drinking water treatment processes (e.g., enhanced coagulation, air flotation, advanced adsorbents, and membrane technologies), detection of residual M-NPs, and biotoxicological assessment as promising and ecofriendly candidates to efficiently remove M-NPs and avoid the release of secondary hazards.


Subject(s)
Drinking Water , Water Pollutants, Chemical , Water Purification , Humans , Microplastics , Disinfection , Chlorine , Water Pollutants, Chemical/analysis
10.
Chemosphere ; 317: 137877, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36649893

ABSTRACT

The widespread presence of microplastics (MPs) has garnered attention owing to their possible adverse effects. However, the cardiotoxicity of MPs and their underlying mechanism remains unclear. N6-methyladenosine (m6A) modification contributes to post-transcriptional modulation of gene expression, but whether this modification is relevant to MP-induced cardiotoxicity is unknown. First, we detected damage to the myocardial tissue among MP-exposed and -unexposed (control) mice by staining them with hematoxylin and eosin, Masson trichrome, and Oil Red O. Then, we comprehensively measured the transcriptome-wide m6A methylome and m6A-altered genes using high-throughput sequencing assays, such as methylated RNA immunoprecipitation sequencing and RNA sequencing. Our data indicated MP-induced myocardial inflammatory injury and histological alterations in vivo, evidenced by the severity of cardiac fibrosis and increased lipid accumulation. We found 878 increased and 316 decreased methylation peaks mostly distributed in the 3' UTR among the MP-exposed group compared with the control group. We found 779 upregulated and 340 downregulated genes in the MP-exposed group. In addition, conjoint analysis of results from the two high-throughput sequencings showed that 109 and 11 hypermethylated genes were upregulated and downregulated, respectively; 12 and 21 hypomethylated genes were upregulated and downregulated, respectively. Results of the cross-link analysis showed that several potential signals, such as ECM-receptor interactions, cell adhesion molecules, cytokine-cytokine receptor interactions, and NF-κB signaling, contributed to MP-induced cardiotoxicity. Our findings indicated that m6A modifications of genes were involved in MP-induced cardiotoxicity and reported new information regarding the chronic cardiotoxicity caused by MP exposure in mice.


Subject(s)
Microplastics , Transcriptome , Mice , Animals , Plastics , Cardiotoxicity , Methylation
11.
Molecules ; 27(20)2022 Oct 19.
Article in English | MEDLINE | ID: mdl-36296657

ABSTRACT

The nonradical process in the peroxydisulfate (PDS) oxidation system is a promising method for antibiotic removal in water. In this study, CuO@CNT was successfully synthesized by a facile approach to catalyze PDS. The removal efficiency of the antibiotic sulfamethoxazole (SMX) was 90.6% in 50 min, and the stoichiometric efficiency (ΔSMX/ΔPDS) was 0.402. The very different degradation efficiency of common organic contaminants revealed the selective oxidation of the surveyed system. The process of 1O2 oxidation and the electron-transfer regime was exhibited by chemical quenching tests, electron paramagnetic resonance (EPR) determination, a UV-vis spectrophotometer, X-ray photoelectron spectroscopy (XPS) detection, and cyclic voltammetry (CV) measurements. Sustainable catalysis was promoted by the circulation between the surface electron-rich centers of Cu(II) and Cu(III). Dissolved oxygen (DO) and a metastable Cu(III) intermediate contributed to the generation of 1O2. Still, a portion of SMX was removed by the mildly activated PDS. Moreover, the influence factors (pH, dosage, water matrix) were examined, and suppressions were acceptable by common anions and real water. Distinguished from the radical process, unique intermediate products were ascertained via the theoretical calculation and liquid chromatography-mass spectrometry (LC-MS) detection. Furthermore, CuO@CNT showed a satisfactory activation ability in the cycling experiments. Overall, this study developed CNT to be a supporter of CuO, unveiled the mechanism of catalysis, and evaluated the application potential of the nonradical process.


Subject(s)
Anti-Bacterial Agents , Electrons , Oxidation-Reduction , Catalysis , Oxygen , Water , Sulfamethoxazole
12.
Sensors (Basel) ; 22(16)2022 Aug 21.
Article in English | MEDLINE | ID: mdl-36016052

ABSTRACT

Light field (LF) image depth estimation is a critical technique for LF-related applications such as 3D reconstruction, target detection, and tracking. The refocusing property of LF images provide rich information for depth estimations; however, it is still challenging in cases of occlusion regions, edge regions, noise interference, etc. The epipolar plane image (EPI) of LF can effectively deal with the depth estimation because of its characteristics of multidirectionality and pixel consistency-in which the LF depth estimations are converted to calculate the EPI slope. This paper proposed an EPI LF depth estimation algorithm based on a directional relationship model and attention mechanism. Unlike the subaperture LF depth estimation method, the proposed method takes EPIs as input images. Specifically, a directional relationship model was used to extract direction features of the horizontal and vertical EPIs, respectively. Then, a multiviewpoint attention mechanism combining channel attention and spatial attention is used to give more weight to the EPI slope information. Subsequently, multiple residual modules are used to eliminate the redundant features that interfere with the EPI slope information-in which a small stride convolution operation is used to avoid losing key EPI slope information. The experimental results revealed that the proposed algorithm outperformed the compared algorithms in terms of accuracy.


Subject(s)
Algorithms , Echo-Planar Imaging
13.
Chemosphere ; 304: 135321, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35718033

ABSTRACT

Investigating the long-term effects of microplastics (MPs) in vivo is necessary for evaluating its biological toxicity. Previously, we showed that MPs elicit vascular dysfunctions in atherosclerotic mice. However, the effects of long-term treatment with environmental levels of MPs on biological functions and RNA expression profiles in wild-type mice are unknown. Here, C57BL/6 mice were administered 1000 µg/L MPs through their drinking water for 180 days. Transcriptomic analyses, biochemical analysis, and histopathological examination were conducted to determine the key signals and molecular mechanisms triggered by MPs in vivo using whole transcriptome sequencing, enzyme-linked immunosorbent assay, and histopathological analysis. Notably, our data revealed that MPs aggravated vascular lesions and organ injuries, particularly liver, kidney, and heart injuries. Additionally, MPs exacerbated oxidative injuries by inhibiting the activities of antioxidant enzymes and increasing the levels of the serum biochemistry indicator of organ damage. RNA sequencing of vascular tissues showed that 674 mRNAs, 39 lncRNAs, 196 miRNAs, and 565 circRNAs were abnormally expressed in MPs-treated mice compared with the untreated group. Pathway enrichment analyses identified pathways linked to the toxicity of MPs, including lysosomal, NOD-like receptor, and peroxisome proliferator-activated receptor pathways. Additionally, competing endogenous RNA networks were constructed and hub RNAs were identified using bioinformatics analysis. Taken together, our data suggested that toxicity induced by long-term exposure to MPs continually presents with extensive changes in biological features and global gene expression profiles. Our data provides new insights into the biological toxicity of MPs.


Subject(s)
MicroRNAs , RNA, Long Noncoding , Animals , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , Microplastics , Plastics , RNA, Long Noncoding/metabolism , Transcriptome , Exome Sequencing
14.
Opt Express ; 29(19): 30077-30093, 2021 Sep 13.
Article in English | MEDLINE | ID: mdl-34614738

ABSTRACT

Depth estimation is a fundamental task in light field (LF) related applications. However, conventional light field suffers from the lack of features, which introduces depth ambiguity and heavy computation load to depth estimation. In this paper, we introduce phase light field (PLF), which uses sinusoidal fringes as patterns and the latent phases as the codes. With PLF and the re-formatted phase-epipolar-plane-images (phase EPIs), a global cost minimization framework is proposed to estimate the depth. In general, EPI-based depth estimation tests a set of candidate lines to find the optimal one with most similar intensities, and the slope of the optimal line is converted to disparity and depth. Based on this principle, for phase-EPI, we propose a cost with weighted phase variance in the candidate line, and we prove that the cost is a convex function. After that, the beetle antennae search (BAS) optimization algorithm is utilized to find the optimal line and thus depth can be obtained. Finally, a bilateral filter is incorporated to further improve the depth quality. Simulation and real experimental results demonstrate that, the proposed method can produce accurate depth maps, especially at boundary regions. Moreover, the proposed method achieves an acceleration of about 5.9 times over the state-of-the-art refocus method with comparable depth quality, and thus can facilitate practical applications.

15.
Environ Toxicol ; 36(8): 1674-1682, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33974337

ABSTRACT

Brominated flame retardants (BFRs), such as, 1,2,5,6-tetrabromocyclooctane (HBCD), 1,2-dibromo-4-(1,2-dibromopropyl)cyclohexane (TBECH), and 1 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE), have garnered increasing attention due to their potent biological effects. In the present study, the toxicity of HBCD, TBECH, and BTBPE in human vascular endothelial cells (ECs) was explored. The data showed that HBCD, TBECH, and BTBPE induced cytotoxicity, namely dose-dependent cell viability reduction, cell membrane permeability and apoptosis increase, migration, and lumen formation inhibition. Moreover, HBCD was found to be more toxic than BTBPE or TBECH. Exposure to HBCD, TBECH, and BTBPE led to the production of reactive oxygen species, mitochondrial superoxide generation, and mitochondrial membrane potential collapse, implying that reactive stress caused the cytotoxicity. The ATP content, glutathione content, superoxide dismutase, and MDA activities were reduced, indicating that mitochondrial dysfunction may be the key mechanisms responsible for apoptosis. The present study suggested that mitochondria are a new target of BFRs in ECs and further deepened our understanding of the developmental toxicity of BFRs.


Subject(s)
Endothelial Cells , Flame Retardants , Humans , Membrane Potential, Mitochondrial , Mitochondria , Reactive Oxygen Species
16.
J Hazard Mater ; 416: 125796, 2021 08 15.
Article in English | MEDLINE | ID: mdl-33838508

ABSTRACT

The N, S co-doped biochar (N, S-BC) with multistage pore structure was successfully synthesized from nanocellulose and thiourea by one-step pyrolysis, which could effectively activate peroxymonosulfate (PMS) to degrade sulfamethoxazole (SMX) in water. Moreover, the removal efficiency of SMX by this oxidation system was 2.3-3.1 times than that of other systems activated by common metal oxides (such as Fe3O4、Fe2O3, and MnO2). More importantly, the mechanism of the N, S-BC/PMS process was deduced by reactive oxygen species (ROS) quenching experiment and electron paramagnetic resonance (EPR) test, which exhibited that surface-bound free radicals and singlet oxygen (1O2) played an essential role in the SMX degradation. Surprisingly, the sulfate radical (SO4•-) and hydroxyl radical (•OH) produced in this system existed in a bound state on the surface of the carbon catalyst to react with SMX, rather than dispersed in the aqueous solution. This particular form of free radicals could resist the influence of background substances and pH changes in water, and maintain excellent SMX degradation efficiency under different water matrices and pH. This study provides a new insight into the application of carbon catalyst in actual water pollution control.


Subject(s)
Nitrogen , Water Pollutants, Chemical , Charcoal , Manganese Compounds , Oxides , Peroxides , Sulfur , Thiourea , Water Pollutants, Chemical/analysis
17.
Environ Sci Technol ; 54(22): 14646-14655, 2020 11 17.
Article in English | MEDLINE | ID: mdl-33118354

ABSTRACT

Up-flow biological activated carbon (BAC) filters have been empirically employed in drinking water treatment plants (DWTPs) to address the challenges of its down-flow counterparts (e.g., high head loss and insufficient use of BAC beds), yet their performances and mechanisms toward ammonia removal are not fully evaluated. This study characterized the occurrence, distribution, and diversities of nitrifiers in up-flow and down-flow BAC filters by investigating 18 full-scale drinking water treatment trains in different geographic locations. Quantitative polymerase chain reaction analysis of gene markers of target microorganisms demonstrated higher numbers of total bacteria, ammonia-oxidizing bacteria (AOB), and Nitrospira in the up-flow filters relative to the down-flow filters (P < 0.05), implying enhanced biological activities and nitrification potential within up-flow filters. The dominance of ammonia-oxidizing archaea (AOA) over AOB (i.e., 1.3-4.0 log10 gene copies higher) in 17 BAC filters illustrated the critical role of AOA in drinking water nitrification. Stratification of biomass was mainly found in the down-flow filters rather than the up-flow filters, suggesting better mixing of filter media across up-flow filter beds. Analysis of similarity results revealed that the AOA and Nitrospira community compositions were mainly affected by water sources and locations (P < 0.05) but not flow configurations. These results provide insight into nitrification mechanisms in BAC filters with different flow configurations in real-world DWTPs.


Subject(s)
Drinking Water , Ammonia , Archaea/genetics , Charcoal , Drinking Water/analysis , Nitrification , Oxidation-Reduction , Phylogeny , Soil Microbiology
18.
Medicine (Baltimore) ; 99(44): e22720, 2020 Oct 30.
Article in English | MEDLINE | ID: mdl-33126309

ABSTRACT

During December 2019, an outbreak of unexplained pneumonia occurred in Wuhan, Hubei Province. The disease was subsequently named coronavirus disease 2019 (COVID-19) and the causative virus as severe acute respiratory syndrome conronavirus-2 (SARS-CoV-2). Based on experience, it is vital to exclude or diagnose suspected patients as soon as possible to prevent disease spread. Our hospital is a COVID-19 designated hospital in Wuhan. During the epidemic period, there was a reconstruction of the medical facilities to accommodate patients with different disease status. We document the development of "suspected ward," a ward that cared for patients with suspected COVID-19, in a large designated hospital during the COVID-19 outbreak in Wuhan City, China, and explain the suspected ward spatial layout, organization structure, diagnosis, and treatment flow chart of suspected cases. The key characteristics of our "suspected ward" is isolation, triage, fast diagnosis, and rapid referral. Our description of this suspected ward provides a reference for further improvements in the care of patients with suspected disease in emergency medical institutions.


Subject(s)
Coronavirus Infections/therapy , Hospital Departments/organization & administration , Infectious Disease Medicine/organization & administration , Pneumonia, Viral/therapy , Betacoronavirus/isolation & purification , COVID-19 , China/epidemiology , Coronavirus Infections/diagnosis , Coronavirus Infections/mortality , Humans , Pandemics , Pneumonia, Viral/diagnosis , Pneumonia, Viral/mortality , Quality Improvement , SARS-CoV-2
19.
Environ Sci Technol ; 54(17): 10944-10953, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32786586

ABSTRACT

Regeneration is required to restore the adsorption performance of activated carbon used as an adsorbent in water purification. Conventional thermal and electrochemical regenerations have high energy consumption and poor mineralization of pollutants, respectively. In this study, phenol-saturated activated carbon fiber was regenerated in situ using an electro-peroxymonosulfate (E-PMS) process, which mineralized the desorbed contaminants with relatively low energy consumption. The initial adsorbed phenol (81.90%) was mineralized, and only 4.07% of the initial concentration remained in the solution after 6 h of E-PMS regeneration. The phenol degradation was dominated by hydroxyl radical oxidation. Adding the PMS in three doses at 2 h intervals improves the regeneration performance from 75% to more than 82%. Regeneration retained 60% of its initial effectiveness even in the 10th cycle with 4.40% of the initial concentration of phenol remaining in the solution. These results confirm the E-PMS regeneration process as effective, sustainable, and environmentally friendly for regenerating activated carbon.


Subject(s)
Charcoal , Water Pollutants, Chemical , Carbon Fiber , Oxidation-Reduction , Peroxides , Phenol , Phenols , Water Pollutants, Chemical/analysis
20.
Chemosphere ; 258: 127120, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32544808

ABSTRACT

Diclofenac (DCF) control measures have become an area of increased interest for environmental researchers due to the high environmental concentration and risk of DCF. Adsorption seems to be promising for DCF removal from the aqueous phase because of its specific superiority in comparison with biodegradation, membrane separation, and advanced oxidation or reduction. In this study, OMS-2 and metal-doped OMS-2 ((Me-OMS-2, with Me = Co, Cu or Ce) were prepared and tested as adsorbents for the removal of DCF. It was evident that the maximum adsorption capacity and rate of Ce-OMS-2 were much higher than those of the other adsorbents, which could be attributed to its large specific surface area and stereoscopic aperture structure. The experimental data are fitted the pseudo-second-order model, the Elovich equation and the Langmuir model well; moreover, the process is an endothermic and spontaneous thermodynamic process, during which the entropy increased, based on the experimental results, indicating that chemisorption was dominant during the DCF adsorption process onto Ce-OMS-2. By the integral of the peak deconvoluted from the XPS spectrum, the ratio of Mn3+/Mn4+ increased from 0.393 to 0.407, revealing that Mn(IV) is rarely reduced into Mn(III) during the DCF adsorption process.


Subject(s)
Diclofenac/chemistry , Diclofenac/isolation & purification , Manganese/chemistry , Water Pollutants, Chemical/isolation & purification , Adsorption , Electron Spin Resonance Spectroscopy , Humic Substances , Hydrogen-Ion Concentration , Kinetics , Oxidation-Reduction , Thermodynamics , Water , Water Pollutants, Chemical/chemistry
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