Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 175
Filtrar
1.
Environ Sci Technol ; 58(19): 8576-8586, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38696240

RESUMO

Humic acid (HA) is ubiquitous in natural aquatic environments and effectively accelerates decontamination by permanganate (Mn(VII)). However, the detailed mechanism remains uncertain. Herein, the intrinsic mechanisms of HA's impact on phenolics oxidation by Mn(VII) and its intermediate manganese oxo-anions were systematically studied. Results suggested that HA facilitated the transfer of a single electron from Mn(VII), resulting in the sequential formation of Mn(VI) and Mn(V). The formed Mn(V) was further reduced to Mn(III) through a double electron transfer process by HA. Mn(III) was responsible for the HA-boosted oxidation as the active species attacking pollutants, while Mn(VI) and Mn(V) tended to act as intermediate species due to their own instability. In addition, HA could serve as a stabilizer to form a complex with produced Mn(III) and retard the disproportionation of Mn(III). Notably, manganese oxo-anions did not mineralize HA but essentially changed its composition. According to the results of Fourier-transform ion cyclotron resonance mass spectrometry and the second derivative analysis of Fourier-transform infrared spectroscopy, we found that manganese oxo-anions triggered the decomposition of C-H bonds on HA and subsequently produced oxygen-containing functional groups (i.e., C-O). This study might shed new light on the HA/manganese oxo-anion process.


Assuntos
Substâncias Húmicas , Manganês , Oxirredução , Fenóis , Manganês/química , Fenóis/química , Ânions , Compostos de Manganês/química , Óxidos/química , Poluentes Químicos da Água/química
2.
Cell Mol Biol (Noisy-le-grand) ; 70(2): 62-66, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38430040

RESUMO

One of the most prevalent co-operative disorders is postoperative cognitive dysfunction (POCD), however, its pathogenesis remains unclear. Thus, the aim of this work was to evaluate SIRT3's impact on cognitive decline in aged mice under anesthesia. Adeno-associated virus SIRT3 vector (AAV-SIRT3) or empty vector (AAV-VEH) was injected into the hippocampal region of aged mice after sevoflurane induction in order to upregulate the expression of SIRT3. The expression levels of SIRT3, pro-inflammatory cytokines, and apoptotic factors in hippocampus tissues were identified by PCR, Western blotting, TUNEL staining, and enzyme-linked immunosorbent assay (ELISA), and the cognitive function of mice was assessed. The SIRT3 expression was down-regulated in the hippocampal tissue of anesthetized mice. SIRT3 overexpression can improve the learning and memory ability, reduce the escape latency, and increase the residence time in the platform and platform crossing ability of mice. The overexpression of SIRT3 in hippocampus can reduce the oxidative stress response and inflammatory response induced by anesthesia in mice, increase the superoxide dismutase (SOD) expression level, and decrease the expression level of MDA and inflammatory factors in hippocampus. In addition, SIRT3 overexpression can also reduce anesthetic-induced hippocampal cell apoptosis. By reducing the hippocampus mitochondrial oxidative stress response, SIRT3 plays a significant role in the pathophysiology of POCD in mice and is a potential target for POCD treatment and diagnosis.


Assuntos
Disfunção Cognitiva , Complicações Cognitivas Pós-Operatórias , Sirtuína 3 , Animais , Camundongos , Disfunção Cognitiva/genética , Estresse Oxidativo , Complicações Cognitivas Pós-Operatórias/genética , Sevoflurano/efeitos adversos , Sevoflurano/farmacologia , Sirtuína 3/genética , Sirtuína 3/metabolismo
3.
ACS Nano ; 18(13): 9403-9412, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488193

RESUMO

Diatomic-site catalysts (DASCs) inherit the excellent performance of single-atom catalysts (SACs) by utilizing two adjacent atomic metal species to achieve functional complementarity and synergistic effects that improve the carbon dioxide reduction reaction (CO2RR) and H2 evolution reaction (HER) kinetics. Herein, we report a method to further improve the catalytic efficiency of Pt by using Pt and Ru single atoms randomly anchored on a g-C3N4 surface, yielding partial Pt-Ru dimers. The synthesized catalyst exhibits extraordinary photocatalytic activity and stability in both the CO2RR and HER processes. In-depth experimentation, the pH-dependent chemical exchange saturation transfer (CEST) imaging nuclear magnetic resonance (NMR) method, and theoretical analyses reveal that the excellent performance is attributed to orbital coupling between the Pt atoms and the neighboring Ru atoms (mainly dxy and dxz), which decreases the orbital energy levels and weakens the bond strength with intermediates, resulting in improved CO2RR and HER performance. This study successfully applies the pH-dependent CEST imaging NMR method to catalytic reactions, and CO2 adsorption is directly observed using CEST 2D imaging maps. This work presents significant potential for a variety of catalytic reaction applications by systematically designing bimetallic dimers with higher activity and stability.

4.
Water Res ; 255: 121494, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38552485

RESUMO

Contrasting effects of sulfidation on contaminants reduction by zero-valent iron (ZVI) has been reported in literature but the underlying mechanisms remain unclear. Here, under well-controlled conditions, we compared the performance of ZVI and sulfidated ZVI (S-ZVI) toward a series of chlorinated compounds. Results revealed that, although S-ZVI was more reactive than ZVI toward hexachloroethane, pentachloroethane, tetrachloroethylene, and trichloroethene, sulfidation hindered the dechlorination of the other ten tested chlorinated aliphatics by a factor of 1.5-125. Moreover, S-ZVI may lead to an accumulation of toxic partially-dechlorinated products. Analogous to its effects on ZVI reactivity, sulfidation also exerted positive, negligible, or negative effects on the electron efficiency of ZVI. Solvent kinetic isotope effect analysis suggested that direct electron transfer rather than reaction with atomic hydrogen was the dominant reduction mechanism in S-ZVI system. Hence, the sulfidation enhancing effects could be expected only when direct electron transfer is the preferred reduction route for target contaminants. Furthermore, linear free energy relationships analysis indicated one-electron reduction potential could be used to predict the transformation of chlorinated ethanes by S-ZVI, whereas for chlorinated ethenes, their adsorption properties on S-ZVI determined the dechlorination process. All these findings may offer guidance for the decision-making regarding the application of S-ZVI.

5.
Water Res ; 251: 121106, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38183841

RESUMO

The selective transformation of organics from wastewater to value-added chemicals is considered an upcycling process beneficial for carbon neutrality. Herein, we present an innovative electrocatalytic oxidation (ECO) system aimed at achieving the selective conversion of phenols in wastewater to para-benzoquinone (p-BQ), a valuable chemical widely utilized in the manufacturing and chemical industries. Notably, 96.4% of phenol abatement and 78.9% of p-BQ yield are synchronously obtained over a preferred carbon cloth-supported ruthenium nanoparticles (Ru/C) anode. Such unprecedented results stem from the weak Ru-O bond between the Ru active sites and generated p-BQ, which facilitates the desorption of p-BQ from the anode surface. This property not only prevents the excessive oxidation of the generated p-BQ but also reinstates the Ru active sites essential for the rapid ECO of phenol. Furthermore, this ECO system operates at ambient conditions and obviates the need for potent chemical oxidants, establishing a sustainable avenue for p-BQ production. Importantly, the system efficacy can be adaptable in actual phenol-containing coking wastewater, highlighting its potential practical application prospect. As a proof of concept, we construct an electrified Ru/C membrane for ECO of phenol, attaining phenol removal of 95.8% coupled with p-BQ selectivity of 73.1%, which demonstrates the feasibility of the ECO system in a scalable flow-through operation mode. This work provides a promising ECO strategy for realizing both phenols removal and valuable organics recovery from phenolic wastewater.


Assuntos
Benzoquinonas , Águas Residuárias , Poluentes Químicos da Água , Fenol/química , Fenóis , Carbono , Poluentes Químicos da Água/química
6.
J Ovarian Res ; 16(1): 203, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37848988

RESUMO

BACKGROUND: Premature ovarian insufficiency (POI) is an important cause of infertility characterized by the functional decline of the ovary. Granulosa cells (GCs) around oocytes are critical for folliculogenesis, and GC dysfunction is one of the important etiologies of POI. The aim of this study was to explore the potential biomarkers of POI by identifying hub genes and analyze the correlation of biomarkers with immune infiltration in POI using RNA profiling and bioinformatics analysis. METHODS: RNA sequencing was performed on GCs from biochemical POI (bPOI) patients and controls. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were used to explore the candidate genes. qRT‒PCR was performed to verify the expression of hub genes. Western blot, Cell Counting Kit-8, 5-ethynyl-2'-deoxyuridine (EdU) assays, TUNEL (TdT-mediated dUTP Nick-End Labeling) and flow cytometry analysis were used to validate the possible role of ubiquitin-conjugating enzyme 2C (UBE2C) in POI. CIBERSORT was adopted to explore immune cell infiltration and the correlation between UBE2C and immune cells in bPOI. RESULTS: Through analysis of differentially expressed genes (DEGs) and WGCNA, we obtained 143 candidate genes. After construction of the protein‒protein interaction (PPI) network and analysis with Cytoscape, 10 hub genes, including UBE2C, PBK, BUB1, CDC20, NUSAP1, CENPA, CCNB2, TOP2A, AURKB, and FOXM1, were identified and verified by qRT‒PCR. Subsequently, UBE2C was chosen as a possible biomarker of POI because knockdown of UBE2C could inhibit the proliferation and promote the apoptosis of GCs. Immune infiltration analysis indicated that monocytes and M1 macrophages may be associated with the pathogenesis of POI. In addition, UBE2C was negatively correlated with monocytes and M1 macrophages in POI. CONCLUSIONS: This study identified a hub gene in GCs that might be important in the pathogenesis of POI and revealed the key role of UBE2C in driving POI. Immune infiltration may be highly related with the onset and etiology of POI.


Assuntos
Menopausa Precoce , Insuficiência Ovariana Primária , Feminino , Humanos , Transcriptoma , Enzimas de Conjugação de Ubiquitina/genética , Insuficiência Ovariana Primária/genética , Menopausa Precoce/genética , Células da Granulosa , Biomarcadores
7.
Environ Sci Technol ; 57(45): 17620-17628, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37902719

RESUMO

Despite decades of research on phenols oxidation by permanganate, there are still considerable uncertainties regarding the mechanisms accounting for the unexpected parabolic pH-dependent oxidation rate. Herein, the pH effect on phenols oxidation was reinvestigated experimentally and theoretically by highlighting the previously unappreciated proton transfer. The results revealed that the oxidation of protonated phenols occurred via proton-coupled electron transfer (PCET) pathways, which can switch from ETPT (electron transfer followed by proton transfer) to CEPT (concerted electron-proton transfer) or PTET (proton transfer followed by electron transfer) with an increase in pH. A PCET-based model was thus established, and it could fit the kinetic data of phenols oxidation by permanganate well. In contrast with what was previously thought, both the simulating results and the density functional theory calculation indicated the rate of CEPT reaction of protonated phenols with OH- as the proton acceptor was much higher than that of deprotonated phenols, which could account for the pH-rate profiles for phenols oxidation. Analysis of the quantitative structure-activity relationships among the modeled rate constants, Hammett constants, and pKa values of phenols further supports the idea that the oxidation of protonated phenols is dominated by PCET. This study improves our understanding of permanganate oxidation and suggests a new pattern of reactivity that may be applicable to other systems.


Assuntos
Elétrons , Prótons , Concentração de Íons de Hidrogênio , Oxirredução , Transporte de Elétrons , Fenóis , Cinética
8.
Environ Sci Technol ; 57(44): 17144-17153, 2023 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-37877900

RESUMO

Recent research has primarily focused on the utilization of reductants as activators for Fe(VI) to generate high-valent iron species (Fe(IV)/Fe(V)) for the degradation of emerging organic contaminants (EOCs). However, a significant drawback of this approach arises from the reaction between reductants and ferrates, leading to a decrease in oxidation capacity. This study introduces a novel discovery that highlights the potential of the iron(III)-(1,10-phenanthroline) (Fe(III)-Phen) complex as an activator, effectively enhancing the degradation of EOCs by Fe(VI) and augmenting the overall oxidation capacity of Fe(VI). The degradation of EOCs in the Fe(VI)/Fe(III)-Phen system is facilitated through two mechanisms: a direct electron transfer (DET) process and electron shuttle action. The DET process involves the formation of a Phen-Fe(III)-Fe(VI)* complex, which exhibits a stronger oxidation ability than Fe(VI) alone and can accept electrons directly from EOCs. On the other hand, the electron shuttle process utilizes Fe(III)-Phen as a redox mediator to transfer electrons from EOCs to Fe(VI) through the Fe(IV)/Fe(III) or Fe(IV)/Fe(II)/Fe(III) cycle. Moreover, the Fe(III)-Phen complex can improve the utilization efficiency of Fe(V) by preventing its self-decay. This study's findings may present a viable option for utilizing an effective catalyst to enhance the oxidation of EOCs by Fe(VI) and Fe(V).


Assuntos
Poluentes Químicos da Água , Purificação da Água , Compostos Férricos , Elétrons , Substâncias Redutoras , Oxirredução , Ferro
9.
J Hazard Mater ; 460: 132433, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37659238

RESUMO

Attention has been long focused on enhancing permanganate (Mn(VII)) oxidation capacity for eliminating organic contaminants via generating active manganese intermediates (AMnIs). Nevertheless, limited consideration has been given to the unnecessary consumption of Mn(VII) due to the spontaneous disproportionation of AMnIs during their formation. In this work, we innovatively introduced green polyaspartic acid (PASP) as both reducing and chelating agents to activate Mn(VII) to enhance the oxidation capacity and utilization efficiency of Mn(VII). Multiple lines of evidence suggest that Mn(III), existing as Mn(III)-PASP complex, was generated and dominated the degradation of bisphenol A (BPA) in the Mn(VII)/PASP system. The stabilized Mn(III) species enabled Mn(VII) utilization efficiency in the Mn(VII)/PASP system to be higher than that in Mn(VII) alone. Moreover, the electrophilic Mn(III) species was verified to mainly attack the inclusive benzene ring and isopropyl group to realize BPA oxidation and its toxicity reduction in the Mn(VII)/PASP system. In addition, the Mn(VII)/PASP system showed the potential for selectively oxidizing organic contaminants bearing phenol and aniline moieties in real waters without interference from most of coexisting water matrices. This work brightens an overlooked route to both high oxidation capacity and efficient Mn(VII) utilization in the Mn(VII)-based oxidation processes.

10.
Front Pediatr ; 11: 1223615, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37681201

RESUMO

Objective: In the past, obviously displaced lateral condyle fractures of the humerus in children were treated satisfactorily with open reduction and internal fixation (ORIF). However, in recent years, more studies have mentioned closed reduction and percutaneous pinning (CRPP) of these fractures. Methods: In this retrospective investigation, the radiographic and clinical results of patients with these fractures that were initially managed with CRPP were newly classified. We classified these fractures into three groups according to the degree and pattern of fracture displacement as identified on four radiographic images. In Type I, the fracture is unstable and displacement is ≥2 mm; In Type II degree I, the fracture is unstable and displacement is >2 mm, with single rotation of fragment; In Type II degree II, the fracture is unstable and displacement is >2 mm, with single rotation of fragment, with rotation of fragment and antero-proximal displacement; In Type III, the fracture is unstable and displacement is >2 mm, with posterior dislocation of elbow joint. We also designed an algorithm for closed reduction of these fractures according to this new classification. Results: We retrospectively analyzed the radiographic and clinical results of 37 unstable fractures (in 22 boys and 15 girls) that were treated with closed reduction. Twenty-one of 25 (84.0%) type I fractures, which could have been reduced to within 2 mm of residual displacement, were treated with closed reduction and pinning with 2 or 3 Kirschner wires (K wires). Three of 5 (60.0%) type II degree I, 3 of 4 (75.0%) type II degree II, and 3 of 3 (100%) type III fractures were treated with CRPP. In 4 of 25 (16.0%) type I, 2 of 5 (40.0%) type II degree I and 1 of 4 (25.0%) type II degree II fractures, closed reduction failed, so ORIF was implemented. There were no complications, such as nonunion, osteonecrosis of the capitellum, superficial or deep infection, malunion, cubitus varus or valgus, or early physeal arrest. Conclusion: Although the management of type III fractures may not be more difficult than type II fractures with a rotated fracture fragment, as elbow dislocations are usually easy reducible. This retrospective study showed that type III fractures should not be ignored as a lateral condyle fracture that can be cured with CRPP and that lateral humeral condyle fractures with obvious displacement and rotation can be initially treated with CRPP to achieve satisfactory recovery of the elbow. Kirschner wire (K wire) fixation is recommended to avoid reoperation or anesthesia for hardware removal.

11.
Water Res ; 244: 120507, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37639991

RESUMO

Mn(II) exhibits a superb ability in activating periodate (PI) for the efficient degradation of aqueous organic contaminants. Nevertheless, ambiguous conclusions regarding the involved reactive species contributing to the removal of organic contaminants remain unresolved. In this work, we found that the Mn(II)/PI process showed outstanding and selective reactivity for oxidizing sulfonamides with the removal ranging from 57.1% to 100% at pH 6.5. Many lines of evidence suggest that the in-situ formed colloidal MnO2 (cMnO2) served as a catalyst to mediate electron transfer from sulfonamides to PI on its surface via forming cMnO2-PI complex (cMnO2-PI*) for the efficient oxidation of sulfonamides in the Mn(II)/PI process. Experimental results and density functional theory (DFT) calculations verify that the inclusive aniline moiety was the key site determining the electron transfer-dominated oxidation of sulfonamides. Furthermore, DFT calculation results reveal that the discrepancies in the removal of sulfonamides in the Mn(II)/PI process were attributed to different kinetic stability and chemical reactivity of sulfonamides caused by their heterocyclic substituents. In addition, a high utilization efficiency of PI was achieved in the Mn(II)/PI process owing to the surface-mediated electron transfer mechanism. This work provides deep insights into the surface-promoted mechanism in the cMnO2-involved oxidation processes.


Assuntos
Antibacterianos , Compostos de Manganês , Óxidos , Elétrons , Oxirredução , Sulfanilamida , Sulfonamidas
12.
Environ Sci Technol ; 57(46): 18193-18202, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37406199

RESUMO

In this study, we introduce the count-based Morgan fingerprint (C-MF) to represent chemical structures of contaminants and develop machine learning (ML)-based predictive models for their activities and properties. Compared with the binary Morgan fingerprint (B-MF), C-MF not only qualifies the presence or absence of an atom group but also quantifies its counts in a molecule. We employ six different ML algorithms (ridge regression, SVM, KNN, RF, XGBoost, and CatBoost) to develop models on 10 contaminant-related data sets based on C-MF and B-MF to compare them in terms of the model's predictive performance, interpretation, and applicability domain (AD). Our results show that C-MF outperforms B-MF in nine of 10 data sets in terms of model predictive performance. The advantage of C-MF over B-MF is dependent on the ML algorithm, and the performance enhancements are proportional to the difference in the chemical diversity of data sets calculated by B-MF and C-MF. Model interpretation results show that the C-MF-based model can elucidate the effect of atom group counts on the target and have a wider range of SHAP values. AD analysis shows that C-MF-based models have an AD similar to that of B-MF-based ones. Finally, we developed a "ContaminaNET" platform to deploy these C-MF-based models for free use.


Assuntos
Algoritmos , Aprendizado de Máquina , Poluição Química da Água , Água/química , Poluição Química da Água/análise
13.
Environ Sci Technol ; 57(25): 9332-9341, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37294905

RESUMO

Fe(IV) and Fe(V) are promising oxidants for the selective removal of emerging organic contaminants (EOCs) from water under near-neutral conditions. The Fe(III)-assisted electrochemical oxidation system with a BDD anode (Fe(III)-EOS-BDD system) has been employed to generate Fe(VI), while the generation and contributions of Fe(IV) and Fe(V) have been largely ignored. Thus, we examined the feasibility and involved mechanisms of the selective degradation of EOCs in the Fe(III)-EOS-BDD system under near-neutral conditions. It was found that Fe(III) application selectively accelerated the electro-oxidation of phenolic and sulfonamide organics and made the oxidation system be resistant to interference from Cl-, HCO3-, and humic acid. Several lines of evidence indicated that EOCs were decomposed via direct electron-transfer process on the BDD anode and by Fe(IV) and Fe(V) but not Fe(VI), besides HO•. Fe(VI) was not generated until the exhaustion of EOCs. Furthermore, the overall contributions of Fe(IV) and Fe(V) to the oxidation of phenolic and sulfonamide organics were over 45%. Our results also revealed that Fe(III) was oxidized primarily by HO• to Fe(IV) and Fe(V) in the Fe(III)-EOS-BDD system. This study advances the understanding of the roles of Fe(IV) and Fe(V) in the Fe(III)-EOS-BDD system and provides an alternative for utilizing Fe(IV) and Fe(V) under near-neutral conditions.


Assuntos
Diamante , Poluentes Químicos da Água , Boro , Compostos Férricos , Água , Oxidantes , Oxirredução , Eletrodos
14.
Environ Sci Technol ; 57(23): 8818-8827, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37166095

RESUMO

Current techniques for identifying and quantifying sulfate radicals (SO4·-) in SO4·--based advanced oxidation processes (SR-AOPs) are unsatisfactory due to their low selectivity, poor reliability, and limited feasibility for real-time quantification. In this study, naproxen (NAP) was employed as a turn-on luminescent probe for real-time quantification of SO4·- in SR-AOPs. The chemiluminescence(CL) yield (ΦCL) of the reaction of NAP with SO4·- was first determined to be 1.49 × 10-5 E mol-1 with the bisulfite activation by cerium(IV) [Ce(IV)/BS] process. Then, the maximum peak concentrations of SO4·- in the Ce(IV)/BS-NAP process was quantified to be ∼10-11 M based on the derived equation. Since ΦCL of the reaction of NAP with SO4·- was much greater than that with other reactive oxidizing species (ROS), the developed CL method worked well in selective quantification of SO4·- in various SR-AOPs (e.g., the activation of peroxymonosulfate and persulfate by iron processes). Finally, the electron transfer from NAP to SO4·- was proposed to be the critical step for CL production. This work provides a novel CL method for real-time quantification of SO4·-, which facilitates the development of SR-AOPs and their application in water and wastewater treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Naproxeno , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Oxirredução , Sulfatos
15.
Water Res ; 238: 119987, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37121198

RESUMO

Pyrrhotite is ubiquitously found in natural environment and involved in diverse (bio)processes. However, the pyrrhotite-driven bioreduction of toxic selenate [Se(VI)] remains largely unknown. This study demonstrates that Se(VI) is successfully bioreduced under anaerobic condition with the participation of pyrrhotite for the first time. Completely removal of Se(VI) was achieved at initial concentration of 10 mg/L Se(VI) and 0.56 mL/min flow rate in continuous column experiment with indigenous microbial consortium and pyrrhotite. Variation in hydrochemistry and hydrodynamics affected Se(VI) removal performance. Se(VI) was reduced to insoluble Se(0) while elements in pyrrhotite were oxidized to Fe(III) and SO42-. Breakthrough study indicated that biotic activity contributed 81.4 ± 1.07% to Se(VI) transformation. Microbial community analysis suggested that chemoautotrophic genera (e.g., Thiobacillus) could realize pyrrhotite oxidation and Se(VI) reduction independently, while heterotrophic genera (e.g., Bacillus, Pseudomonas) contributed to Se(VI) detoxification by utilizing metabolic intermediates generated through Fe(II) and S(-II) oxidation, which were further verified by pure culture tests. Metagenomic and qPCR analyses indicated genes encoding enzymes for Se(VI) reduction (e.g., serA, napA and srdBAC), S oxidation (e.g., soxB) and Fe oxidation (e.g., mtrA) were upregulated. The elevated electron transporters (e.g., nicotinamide adenine dinucleotide, cytochrome c) promoted electron transfer from pyrrhotite to Se(VI). This study gains insights into Se biogeochemistry under the effect of Fe(II)-bearing minerals and provides a sustainable strategy for Se(VI) bioremediation in natural aquifer.


Assuntos
Água Subterrânea , Consórcios Microbianos , Ácido Selênico , Compostos Férricos , Oxirredução , Compostos Ferrosos
16.
Heliyon ; 9(3): e14423, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36950567

RESUMO

Objective: Living kidney donors (LKDs) experience perioperative anxiety. We designed the following study to evaluate the anxiolytic effect of transcutaneous electrical acupoint stimulation (TEAS) during the perioperative period in a group of LKDs undergoing laparotomy nephrectomy. Methods: LKDs were randomly assigned to either the TEAS or control group. Participants in the TEAS group received 30min of intervention (6-15 mA, 2-100 Hz), at Yintang (EX-HN-3), bilateral Taichong (LR3) and Neiguan (PC6) one day before surgery (D0), before induction of anesthesia (D1) and one day after surgery (D2). The participants in the control group received the same placement of electrodes but without electrical stimulation. Venous blood was collected before each intervention. Anxiety levels and recovery profiles were recorded. Results: LKDs in the TEAS group had lower anxiety level than those in the control group at D1, D2 and three days after surgery (D3). The percentage differences were: 33.3%, 25.0%, and 22.2%; [95% confidence interval (CI), (-55.1%, -11.6%), (-47.4%, -2.6%), and (-42.3%, -2.2%); P = 0.005, P = 0.034, and P = 0.035; respectively]. LKDs who received TEAS had better sleep quality and short-term recovery profiles than those in the control group. The plasma levels of 5-hydroxytryptamine (5-HT) and melatonin (MT) in the TEAS group were significantly higher than those in the control group at D1 and D2 (5-HT: P = 0.001, and P < 0.001; MT: P = 0.006, and P = 0.001). At the 3-month follow up, fewer LKDs in the TEAS group had incisional pain when compared to the control group (P = 0.032). Conclusions: Perioperative TEAS decreased perioperative anxiety and facilitated postoperative recovery in the LKDs, and potential decreased the development of chronic pain. Trial Registration: Registered at ChiCTR2000029891, http://www.chictr.org.cn/listbycreater.aspx.

17.
Ann Transplant ; 28: e939149, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36851833

RESUMO

BACKGROUND Cystatin C (Cys) is considered to be a better marker than serum creatinine in assessing kidney function, predicting cardiovascular events, and all-cause mortality. It seems to be associated with nutritional status in the general population, but little is known about kidney transplant recipients (KTRs). This study aimed to explore the relationship between dietary balance index and serum Cys in KTRs. MATERIAL AND METHODS In a cross-sectional study, 215 KTRs completed an FFQ questionnaire and information on serum Cys. Dietary intake was assessed using the Food Frequency Questionnaire (FFQ). Dietary Balance Index 2016 (DBI-16) edition scores were calculated as an indicator of dietary quality. Data on the patient's serum Cys were obtained through the hospital information system. RESULTS The majority of KTRs were male (75.34%), 76.74% were aged 18-44 years, and 79.53% were abnormal serum Cys. Dairy (z=-2.161, P<0.05), meat (z=-2.578, P<0.05), and dietary diversity (z=-3.393, P<0.05) in the normal group were higher than those in the abnormal group, and the dietary quality distance (DQD) score (t=-2.264, P<0.05) was lower than that in the abnormal group. After adjusting for confounders, a low-quality diet was a risk factor for maintaining the normal level of serum Cys (OR 3.022, 95% CI 1.263-7.231, P<0.05). CONCLUSIONS The present study suggested that KTRs with a high dietary quality might be associated with normal serum Cys levels. Dairy, meat, and varied diet seems to impact the serum Cys levels of KTRs. Dietary imbalances were prevalent among KTRs.


Assuntos
Cistatina C , Dieta , Transplante de Rim , Feminino , Humanos , Masculino , Estudos Transversais , Cistatina C/sangue , População do Leste Asiático , Transplantados , Adolescente , Adulto Jovem , Adulto
18.
Environ Sci Technol ; 57(2): 997-1005, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36583974

RESUMO

Although intermediate manganese species can be generated during the reactions of permanganate (Mn(VII)) with organic pollutants in water, the role of the in situ generated MnO2 colloids in the Mn(VII) oxidation process remained controversial and the contribution of Mn(III) was largely neglected. This study showed that the apparent second-order rate constants (kapp) of Mn(VII) oxidation of methyl phenyl sulfoxide and carbamazepine remained constant with time. However, the degradation of four selected phenolic contaminants by Mn(VII) exhibited an autoaccelerating trend and a linear trend at pH 3.0-6.0 and pH 7.0-9.0, respectively. Multiple lines of evidence revealed that the occurrence of the autoaccelerating trend in the Mn(VII) oxidation process was ascribed to the oxidation of the phenolic organics by MnO2 colloids. The influence of pyrophosphate on the oxidation of different organic contaminants by MnO2 colloids suggests that Mn(III) was also responsible for the autoaccelerating oxidation of organic contaminants by Mn(VII) under specific reaction conditions. The kinetic models revealed that the overall contributions of MnO2 colloids and Mn(III) ranged within 6.6-67.9% during the autoaccelerating oxidation of phenolic contaminants by Mn(VII). These findings advance the understanding of the roles of MnO2 colloids and Mn(III) in the Mn(VII) oxidation process.


Assuntos
Compostos de Manganês , Óxidos , Oxirredução , Fenóis , Coloides , Cinética
19.
IEEE Trans Neural Netw Learn Syst ; 34(9): 5654-5668, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34878981

RESUMO

Among the prohibitively large volume of posts (e.g., tweets in Twitter) on online social networks (OSNs), how to design effective queries to explore the ones of interest is a pressing problem. There are two main challenges to address the problem. First, given public application programming interfaces (APIs) for querying posts related to keywords from an extremely large vocabulary, how to infer the keywords relevant to our target interest using as few queries as possible? Second, how to deal with the agnostics of OSN's API? i.e., as different social networks typically have different running mechanisms, even with some randomness in returning results, how to build the knowledge of the API returns w.r.t. target interests from scratches? To address the above two challenges, we propose a target query discovery framework based on a deep reinforcement learning approach, named SocialSift. SocialSift intelligently interacts with OSNs' keyword-based API and develops its own knowledge in searching the optimal queries w.r.t. the target interests as well as OSN APIs. Specifically, to address the first challenge, we are inspired by the human searching experience, and recognize learning to query with context awareness to reduce the searching space, by qualifying keywords from returned results and keeping the tracks of the query trial history, or say contexts. As for addressing the second challenge, we treat OSNs' APIs as black boxes and probabilistically quantify query-interest pairs guided by rewards, which is a well-curated indicator w.r.t. target interests. Empirical results on three popular OSNs: Twitter, Reddit, and Amazon demonstrate our SocialSift significantly outperforms the state-of-the-art baselines by 12% in retrieving target posts.

20.
Front Endocrinol (Lausanne) ; 13: 1038184, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36518256

RESUMO

Background: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting reproductive age females and an important cause of infertility. Although the etiology is complex and its pathogenesis remains unclear, the pathological process of PCOS is tightly related with the immune dysfunction and gut microbial dysbiosis. Mucosal-associated invariant T (MAIT) cells are a subset of innate-like T cells which can regulate inflammation through the production of cytokines and play a role in regulating the gut microbiota. We aim to evaluate the correlation between characteristics of PCOS and MAIT cells as well as their impact on cytokine secretion. Methods: Peripheral blood samples were taken from PCOS patients (n=33) and healthy controls (n=30) during 2-5 days of the menstrual period. The frequencies of MAIT cells and T cells were measured by flow cytometry. Cytokines interleukin 17 (IL-17), interleukin 22(IL-22), interferon γ (IFN-γ) and granzyme B were determined by Enzyme-linked immunosorbent assay (ELISA). Results: The frequency of MAIT cells was significantly reduced in the blood of PCOS patients compared with the controls, and negatively correlated with Body Mass Index (BMI), Homeostatic model assessment- insulin resistance (HOMA-IR) index, and Anti Miillerian Hormone (AMH). Thus, the frequencies of MAIT cells decreased in PCOS patients with abnormal weight (BMI≥24kg/m2), higher HOMA-IR (≥1.5), and excessive AMH (≥8ng/ml). The Cytokine IL-17 was significantly higher in PCOS patients and negatively correlated with the frequency of MAIT cells. Even though the IL-22 was lower in PCOS Patients, no correlation with MAIT cells was detected. In subgroup, CD4+MAIT cells correlated with BMI, AMH, and testosterone (T) levels. Conclusion: The frequency change of MAIT cells may play a significant role in the pathogenesis of PCOS. Exploring these interactions with MAIT cells may provide a new target for PCOS treatment and prevention.


Assuntos
Resistência à Insulina , Células T Invariantes Associadas à Mucosa , Síndrome do Ovário Policístico , Feminino , Humanos , Células T Invariantes Associadas à Mucosa/patologia , Células T Invariantes Associadas à Mucosa/fisiologia , Interleucina-17 , Citocinas
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...