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1.
Environ Res ; 246: 118564, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38417658

RESUMO

Metal-organic frameworks (MOFs) have shown great prospects in wastewater remediation. However, the easy aggregation, difficult separation and inferior reusability greatly limit their large-scale application. Herein, we proposed a facile, green and low-cost strategy to construct robust and stable MOF-based hydrogel beads (Fe-BTC-HBs) in a gram scale, and employed them to remove antibiotics from wastewater. As a result, the Fe-BTC-HBs demonstrated outstanding adsorption capacity for both ofloxacin (OFL) and tetracycline (TC) (281.17 mg/g for OFL and 223.60 mg/g for TC) under a near-neutral environment. The main adsorption mechanisms of OFL and TC were hydrogen bonding and π-π stacking interaction. Owing to its macroscopic granule and stable structure, Fe-BTC-HBs can be separated rapidly from wastewater after capturing antibiotics, and more than 85% adsorption capacity still remained after six cycles, while the powdered Fe-BTC only showed less than 6% recovery efficiency with massive weight loss (around 92%). In real industrial effluent, the adsorption performance of Fe-BTC-HBs toward two antibiotics exhibited negligible decreases (2.9% for OFL and 2.2% for TC) compared with that in corresponding solutions. Furthermore, Fe-BTC-HBs also had appealing economic and environmental benefit. Overall, the macro-manufactured MOF beads have the promising potential for the large-scale wastewater treatment.


Assuntos
Estruturas Metalorgânicas , Poluentes Químicos da Água , Antibacterianos/química , Águas Residuárias , Poluentes Químicos da Água/química , Tetraciclina , Adsorção , Cinética
2.
BMC Plant Biol ; 23(1): 399, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37605165

RESUMO

The environment in Antarctica is characterized by low temperature, intense UVB and few vegetation types. The Pohlia nutans M211 are bryophytes, which are the primary plants in Antarctica and can thrive well in the Antarctic harsh environment. The transcriptional profiling of Pohlia nutans M211 under low temperature and high UVB conditions was analyzed to explore their polar adaptation mechanism in the extreme Antarctic environment by third-generation sequencing and second-generation sequencing. In comparison to earlier second-generation sequencing techniques, a total of 43,101 non-redundant transcripts and 10,532 lncRNA transcripts were obtained, which were longer and more accurate. The analysis results of GO, KEGG, AS (alternative splicing), and WGCNA (weighted gene co-expression network analysis) of DEGs (differentially expressed genes), combined with the biochemical kits revealed that antioxidant, secondary metabolites pathways and photosynthesis were the key adaptive pathways for Pohlia nutans M211 to the Antarctic extreme environment. Furthermore, the low temperature and strong UVB are closely linked for the first time by the gene HY5 (hlongated hypocotyl 5) to form a protein interaction network through the PPI (protein-protein interaction networks) analysis method. The UVR8 module, photosynthetic module, secondary metabolites synthesis module, and temperature response module were the key components of the PPI network. In conclusion, this study will help to further explore the polar adaptation mechanism of Antarctic plants represented by bryophytes and to enrich the polar gene resources.


Assuntos
Briófitas , Bryopsida , Antioxidantes , Regiões Antárticas , Fotossíntese , Briófitas/genética
3.
Cell Mol Neurobiol ; 43(1): 139-153, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34978648

RESUMO

NMDA receptors play an important physiological role in regulating synaptic plasticity, learning and memory. GluN2A subunits are the most abundant functional subunits of NMDA receptors expressed in mature brain, and their dysfunction is related to various neurological diseases. According to subunit composition, GluN2A-containing NMDA receptors can be divided into two types: diheteromeric and triheteromeric receptors. In this review, the expression, functional and pharmacological properties of different kinds of GluN2A-containing NMDA receptors as well as selective GluN2A regulators were described to further understand this type of NMDA receptors.


Assuntos
Plasticidade Neuronal , Receptores de N-Metil-D-Aspartato , Receptores de N-Metil-D-Aspartato/metabolismo , Antagonistas de Aminoácidos Excitatórios/farmacologia
4.
Appl Opt ; 62(36): 9591-9598, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38108785

RESUMO

The OTSU method (OTSU) is considered to be the best algorithm for threshold selection in image segmentation. The algorithm is easy to calculate and not affected by image brightness and contrast, so it is widely used in the field of digital image processing. Due to the slow running speed and large storage space of the algorithm on the traditional electronic computer, this research makes use of the advantages of the ternary optical computer (TOC), such as numerous data bits and the reconfigurable processor. Through the analysis of the OTSU algorithm, we find the part of the OTSU algorithm that can be calculated in parallel, and put forward a parallel OTSU algorithm based on TOC. The algorithm first uses a classifier to classify the number of pixels. By reconstructing the MSD adder and multiplier, the inter-class variance under each gray value is calculated in parallel, and the maximum value is selected by comparing the inter-class variance. The corresponding threshold is the best segmentation threshold. By analyzing the clock cycle and data bit resources of the algorithm, and then conducting a comparative analysis and experimental verification, we found that the computational speed of TOC increased by approximately 12% when handling images with the same amount of computation.

5.
Bioorg Med Chem Lett ; 70: 128805, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35598794

RESUMO

The pharmacological inhibition of soluble epoxide hydrolase (sEH) was shown to reduce inflammation and pain. Herein, we described a series of newly synthesized sEH inhibitors with the trident-shaped skeleton. Intensive structural modifications led to the identification of compound B15 as a potent sEH inhibitor with an IC50 value of 0.03 ± 0.01 nM. Furthermore, compound B15 showed satisfactory metabolic stability in human liver microsomes with a half-time of 197 min. In carrageenan-induced inflammatory pain rat model, compound B15 exhibited a better therapeutic effect compared to t-AUCB and Celecoxib, which demonstrated the proof of potential as anti-inflammatory agents for pain relief.


Assuntos
Inibidores Enzimáticos , Epóxido Hidrolases , Animais , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Inibidores Enzimáticos/química , Dor , Ratos , Relação Estrutura-Atividade , Ureia/farmacologia , Ureia/uso terapêutico
6.
Bioorg Chem ; 127: 105898, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35792317

RESUMO

The elevation of epoxy-fatty acids through inhibition of soluble epoxide hydrolase (sEH) is efficient for the treatment of inflammatory and pain-related diseases. Herein, we reported the discovery of a series of benzamide derivatives containing urea moiety as sEH inhibitors. Intensive structural modifications led to the identification of compound A34 as a potent sEH inhibitor with good physicochemical properties. Molecular docking revealed an additional hydrogen-bonding interaction between the unique amide scaffold and Phe497, contributing to sEH inhibition potency enhancement. Compound A34 exhibited outstanding inhibitory activity against human sEH, with an IC50 value of 0.04 ± 0.01 nM and a Ki value of 0.2 ± 0.1 nM. It also showed moderate systemic drug exposure and oral bioavailability in vivo metabolism studies. In carrageenan-induced inflammatory pain rat model, compound A34 exhibited a better therapeutic effect compared to t-AUCB and Celecoxib. Metabolism studies in vivo together with an inflammatory pain evaluation suggest that A34 may be a viable lead compound for the development of highly potent sEH inhibitors.


Assuntos
Inibidores Enzimáticos , Epóxido Hidrolases , Animais , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Dor , Ratos , Solubilidade , Ureia/farmacologia
7.
Sensors (Basel) ; 22(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35591293

RESUMO

A novel six-axis force/torque sensor (F/T sensor) for an Experimental Module Manipulator (EMM) in the Chinese Space Station (CSS) is developed in this paper. First, we designed the elastomer structure of the F/T sensor and used the analytical method and the finite element method to analyze the strain, in order to accomplish the strain gauges' layout. Then, the electrical system was designed, which mainly realizes the acquisition of force/torque information, temperature and serial communication with the end effector (EE). Following this, we analyzed and designed the adaptability of the F/T sensor to the space environment. After this, the manufacturing process of the sensor was introduced in detail, and the F/T sensor was calibrated by a pulley weight system. Finally, the sensor was tested on the space environment adaptability of mechanical vibration and thermal vacuum on the ground. The test results show that the developed sensor has the ability to accurately measure three-dimensional force and three-dimensional moment information on orbit, which provides necessary conditions for the on-orbit fine operation of EMM.


Assuntos
Fenômenos Mecânicos , China , Torque
8.
J Environ Manage ; 312: 114856, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35325739

RESUMO

To suppress the electron-hole recombination and enhance the electron transfer on carbon nitride, an Fe-doped porous carbon nitride catalyst (Fe/SCN) was synthesized via supramolecular self-assembly method and applied in heterogeneous Fenton activation for efficient tetracycline (TC) degradation. Various characterizations revealed that the catalyst exhibited excellent visible light capture performance and electron transfer capacity. The highest degradation efficiency and mineralization rate of TC (10 mg L-1) were achieved under neutral condition (90.3% and 61.2%, respectively) with the leaching of Fe less than 14 µg L-1. Free radical quenching experiments and spin-resonance spectroscopy characterizations revealed the dominating role of OH in TC degradation, and density functional theory calculation confirmed the formation of Fe-NX and revealed the interaction between Fe sites and H2O2. Three possible pathways of TC degradation were proposed, and the biological inhibition test revealed the potential of Fe/SCN/H2O2 system to reduce environmental risks caused by TC. This work provides a new insight into the design of metal-doped heterogeneous Fenton catalyst for the efficient degradation of antibiotic contaminants in water.


Assuntos
Peróxido de Hidrogênio , Tetraciclina , Antibacterianos , Catálise , Peróxido de Hidrogênio/química , Luz
9.
J Environ Manage ; 301: 113793, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34601347

RESUMO

Municipal wastewater treatment plants (WWTPs) have been regarded as the main receptors of microplastics in industrial and domestic wastewater. The excess sludge they generate is an important carrier for the microplastics to enter the environment. In China, relevant regional studies are still in an initial phase. In this work, microplastics in the sewage sludges at different sampling points of five WWTPs in Nanjing City (an important city in the Yangtze River basin) were investigated, including their abundance, morphology and chemical composition. Furthermore, the influence factors such as population density, economic development level, wastewater source and treatment process were also discussed. The analysis results through optical microscope and FT-IR showed that the detected microplastics were divided into fragments, films, fibers and granules. Their chemical component reached up to 19 species, including small amounts of petroleum resins which was scarcely detected in other studies. Wastewater source was the primary factor influencing the microplastic abundance and size in sludge. And the microplastic shape and chemical components were closely related to the industrial type. Furthermore, because the removal effect on the microplastics with different morphologies were varied with the treatment process, the preliminary suggestions on the technology for particular wastewater were proposed. This study provides partial regional data and analysis for the microplastics contained in the sludge of WWTPs, expecting to provide a certain theoretical support for the operations management of WWTPs and standardized sludge treatment.


Assuntos
Poluentes Químicos da Água , Purificação da Água , China , Monitoramento Ambiental , Microplásticos , Plásticos , Esgotos , Espectroscopia de Infravermelho com Transformada de Fourier , Eliminação de Resíduos Líquidos , Águas Residuárias/análise , Poluentes Químicos da Água/análise
10.
J Neurosci Res ; 99(12): 3204-3221, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34676594

RESUMO

Much evidence has proved that excitotoxicity induced by excessive release of glutamate contributes largely to damage caused by ischemia. In view of the key role played by NMDA receptors in mediating excitotoxicity, compounds against NMDA receptors signaling pathways have become the most promising type of anti-stroke candidate compounds. However, the limited therapeutic time window for neuroprotection is a key factor preventing NMDA receptor-related compounds from showing efficacy in all clinical trials for ischemic stroke. In this perspective, the determination of therapeutic time windows of these kinds of compounds is useful in ensuring a therapeutic effect and accelerating clinical application. This mini-review discussed the therapeutic time windows of compounds against NMDA receptors signaling pathways, described related influence factors and the status of clinical studies. The purpose of this review is to look for compounds with wide therapeutic time windows and better clinical application prospect.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Isquemia Encefálica/tratamento farmacológico , Humanos , Neuroproteção , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismo , Transdução de Sinais , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/metabolismo
11.
Crit Rev Biotechnol ; 41(2): 273-299, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33525937

RESUMO

With the rapid development of industry and agriculture, large amounts of organic pollutants have been released into the environment. Consequently, the degradation of refractory organic pollutants has become one of the toughest challenges in remediation. To solve this problem, intimate coupling of photocatalysis and biodegradation (ICPB) technology, which allows the simultaneous action of photocatalysis and biodegradation and thus integrates the advantages of photocatalytic reactions and biological treatments, was developed recently. ICPB consists mainly of porous carriers, photocatalysts, biofilms, and an illuminated reactor. Under illumination, photocatalysts on the surface of the carriers convert refractory pollutants into biodegradable products through photocatalytic reactions, after which these products are completely degraded by the biofilms cultivated in the carriers. Additionally, the biofilms are protected by the carriers from the harmful light and free radicals generated by the photocatalyst. Compared with traditional technologies, ICPB remarkably improves the degradation efficiency and reduces the cost of bioremediation. In this review, we introduce the origin and mechanisms of ICPB, discuss the development of reactors, carriers, photocatalysts, and biofilms used in ICPB, and summarize the applications of ICPB to treat organic pollutants. Finally, gaps in this research as well as future perspectives are discussed.


Assuntos
Poluentes Ambientais , Biodegradação Ambiental , Biofilmes , Catálise , Titânio
12.
Anticancer Drugs ; 32(9): 950-961, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34016832

RESUMO

This study aims to explore the biological actions of circular RNA (circRNA) ArfGAP with SH3 domain, ankyrin repeat and PH domain 2 (circ_ASAP2, circ_0006089) in cisplatin (DDP) resistance of gastric cancer. Circ_ASAP2, ecto-5'-nucleotidase (NT5E) and miR-330-3p were quantified by quantitative real-time PCR or western blot. The measurements of the IC50 value and cell proliferation were done using 3-[4,5-dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay. Cell colony formation, cell cycle distribution, apoptosis, migration and invasion were evaluated by the colony formation, flow cytometry and transwell assays. Dual-luciferase reporter assay was performed to confirm the targeted relationship between different molecules. The role of circ_ASAP2 in tumor growth was gauged by in vivo animal studies. Circ_ASAP2 and NT5E were overexpressed in DDP-resistant gastric cancer tissues and cells. Knockdown of circ_ASAP2 promoted DDP sensitivity, apoptosis and repressed proliferation, migration and invasion of DDP-resistant gastric cancer cells in vitro and diminished tumor growth in vivo. Moreover, NT5E was a downstream effector of circ_ASAP2 in regulating cell DDP sensitivity and functional behaviors. Mechanistically, circ_ASAP2 directly bound to miR-330-3p to promote NT5E expression. Furthermore, circ_ASAP2 modulated cell DDP sensitivity and functional behaviors by targeting miR-330-3p. Knockdown of circ_ASAP2 promoted DDP sensitivity and suppressed malignant behaviors of DDP-resistant gastric cancer cells through targeting the miR-330-3p/NT5E axis.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , MicroRNAs/metabolismo , RNA Circular/metabolismo , Neoplasias Gástricas/patologia , 5'-Nucleotidase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Proteínas Ligadas por GPI/metabolismo , Proteínas Ativadoras de GTPase/metabolismo , Humanos , Concentração Inibidora 50 , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus
13.
Macromol Rapid Commun ; 42(14): e2100154, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34142406

RESUMO

The hierarchically bicontinuous polystyrene monoliths (HBPMs) with homogeneous skeletons and glycopolymer surfaces are fabricated for the first time based on the medium internal phase emulsion (MIPE) templating method via activator generated by electron transfer for atom transfer radical polymerization (AGET ATRP). The synergistic self-assembly of amphiphilic diblock glycopolymer (ADG) and Pluronic F127 (PF127) at the oil/water interface via hydrogen bonding interaction contributes to the formation of bicontinuous MIPE with deformed neighboring water droplets, resulting in the highly interconnected HBPM after polymerization. There is a bimodal pore size distribution in the HBPM, that is, through pores (150-5000 nm) and mesopores (10-150 nm). The HBPMs as prepared show excellent biocompatibility, homogeneous skeletons, strong mechanical strength, and high bed permeability, overcoming the practical limitations of the second generation of polystyrene (PS) monoliths. Glycoprotein concanavalin A (Con A) can be easily and quickly separated by the HBPM in hydrophilic interaction chromatography (HILIC) mode. These results suggest the HBPMs have great potentials in catalysis, separations, and biomedical applications.


Assuntos
Poliestirenos , Esqueleto , Concanavalina A , Interações Hidrofóbicas e Hidrofílicas , Polimerização
14.
J Environ Manage ; 299: 113590, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34474256

RESUMO

In this work, the removal of ammonia nitrogen and phenol by pulsed discharge plasma (PDP) and modified zeolite was investigated. The Fe-zeolite and Mn-zeolite catalysts were prepared by the impregnation method. Catalysts' morphology, specific surface area, and chemical bond structure were characterized. Based on the pollutants removal experiments, Fe-zeolite (0.01) in the PDP system had better catalytic oxidation of phenol and adsorption effect of ammonia nitrogen. The removal efficiency of the pollutants increased with the increase of discharge voltage and solution conductivity, but decreased with the increase of discharge distance. During the plasma discharge process, the pH value in the solution decreased, and the solution conductivity gradually increased. After PDP/Fe-zeolite system treatment, the toxicity of the wastewater was significantly reduced. This study provided a new treatment method for inorganic and organic pollutants treated by PDP.


Assuntos
Poluentes Químicos da Água , Zeolitas , Amônia , Nitrogênio , Fenol , Fenóis , Poluentes Químicos da Água/análise
15.
J Environ Manage ; 299: 113589, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34467861

RESUMO

In this study, two multifunctional nano-chitosan flocculants (CPAM-NCS1 and CPAM-NCS2) were made through the graft modification of cationic monomer and carboxymethylchitosan (CMCTS) to remove combined contaminants. The effects of various factors (pH, flocculant dosage and hydraulic mixing conditions) on the flocculation performance under single and composite pollution conditions were systematically investigated, the optimal chemical oxygen demand (COD) and the chromaticity removal rates in the dye wastewater were 79.9% and 83.9% at wastewater pH 7, the fast stirring rate 300 rpm, the fast stirring time 8 min, and the dosage of CPAM-NCS1 80 mg/L, respectively. The optimal removal rates of Cu (II) obtained by CPAM-NCS1 and CPAM-NCS2 at were 80.3% and 75.2% at 60 mg/L and the wastewater pH 7, respectively. The optimal removal rates of Cu (II) and disperse orange were 85.3% and 89.4%, respectively, in a composite pollutant system in which Cu (II) and disperse orange coexisted when the pH of the composite system was 9 and the dosage of CPAM -NCS1 was 60 mg/L. This study proved that nanoflocculants made by modifying CMCTS with different structures can demonstrate ideal flocculation removal performance for dye and heavy metal wastewaters.


Assuntos
Metais Pesados , Águas Residuárias , Cátions , Corantes , Floculação
16.
Water Sci Technol ; 84(2): 484-498, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34312353

RESUMO

To cope with the increasingly severe challenges of zinc oxide nanoparticles (ZnO-NPs) in the field of the aquatic environment, this paper uses poly-aluminum ferric chloride (PAFC) and cationic polyacrylamide (CPAM) as coagulants to enhance the removal of ZnO-NPs from water. In two environments (pure-water environment and kaolin environment) that simulate suspended solids, we studied the dosage, pH, precipitation time, and hydraulic power of ZnO-NPs at three different initial concentrations (1, 2, and 30 mg/L). The effects of various conditions on the performance of PAFC, CPAM, and PAFC/CPAM to remove ZnO-NPs were examined. Results showed that the overall removal rate of ZnO-NPs in the kaolin environment was slightly higher than that in the pure-water environment. In contrast the removal rate of ZnO-NPs in the PAFC/CPAM was significantly higher than that of PAFC or CPAM alone. The coagulation removal conditions of ZnO-NPs were optimized using a response-surface model. Under the best conditions, the removal rate of ZnO-NPs with an initial mass concentration of 30 mg/L in the PAFC/CPAM combination in pure-water and kaolin environments was 98.54% and 99.17%, respectively. Finally, by studying the changes in floc size during coagulation, enhanced coagulation was an efficient method of removing ZnO-NPs from water.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Óxido de Zinco , Resinas Acrílicas , Cloretos , Compostos Férricos , Poluentes Químicos da Água/análise
17.
J Environ Sci (China) ; 99: 239-248, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183701

RESUMO

In this study, a high-efficiency cationic flocculant, P(DAC-MAPTAC-AM), was successfully prepared using UV-induced polymerization technology. The monomer Acrylamide (AM): Acryloxyethyl Trimethyl ammonium chloride (DAC): methacrylamido propyl trimethyl ammonium chloride (MAPTAC) ratio, monomer concentration, photoinitiator concentration, urea content, and cationic monomer DAC:MAPTAC ratio, light time, and power of high-pressure mercury lamp were studied. The characteristic groups, characteristic diffraction peaks, and characteristic proton peaks of P(DAC-MAPTAC-AM) were confirmed by fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), 1H nuclear magnetic resonance spectrometer (1H NMR), and scanning electron microscopy (SEM). The effects of dosage, pH value, and velocity gradient (G) value on the removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol by poly aluminum ferric chloride (PAFC), P(DAC-MAPTAC-AM), and PAFC/P(DAC-MAPTAC-AM) in the flocculation treatment of coal chemical wastewater were investigated. Results showed that the optimal conditions for the flocculation of coal chemical wastewater using P(DAC-MAPTAC-AM) alone are as follows: dosage of 8-12 mg/L, G value of 100-250 s - 1, and pH value of 4-8. The optimal dosage of PAFC is 90-150 mg/L with a pH of 2-12. The optimal dosage for PAFC/P(DAC-MAPTAC-AM) is as follows: PAFC dosage of 90-150 mg/L, P(DAC-MAPTAC-AM) dosage of 8-12 mg/L, and pH range of 2-6. When P(DAC-MAPTAC-AM) was used alone, the optimal removal efficiencies of turbidity, COD, ammonia nitrogen, and total phenol were 81.0%, 35.0%, 75.0%, and 80.3%, respectively. PAFC has good tolerance to wastewater pH and good pH buffering. Thus, the flocculation treatment of coal chemical wastewater using the PAFC/P(DAC-MAPTAC-AM) compound also exhibits excellent resistance and buffering capacity.


Assuntos
Carvão Mineral , Águas Residuárias , Acrilamida , Cátions , Floculação
18.
J Environ Sci (China) ; 108: 22-32, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34465434

RESUMO

In this study, three magnetic flocculants with different chelating groups, namely, carboxymethyl chitosan-modified Fe3O4 flocculant (MC), acrylamide-grafted magnetic carboxymethyl chitosan flocculant (MCM), and 2-acrylamide-2-methylpropanesulfonic acid copolyacrylamide-grafted magnetic carboxymethyl chitosan flocculant (MCAA) were prepared, synthesized, and characterized by photopolymerization technology. They were applied to the flocculation removal of Cr(III), Co(II), and Pb(II). The effect of flocculation condition on the removal performance of Cr(III), Co(II), and Pb(II) was studied. Characterization results show that the three magnetic carboxymethyl chitosan-based flocculants have been successfully prepared with good magnetic induction properties. Flocculation results show that the removal rates of MC, MCM, and MCAA on Cr(III) are 51.79%, 82.33%, and 91.42%, respectively, under the conditions of 80 mg/L flocculant, pH value of 6, reaction time of 1.5 hr, G value of 200 s-1, and precipitation magnetic field strength of 120 mT. The removal rates of Co(II) by MC, MCM, and MCAA are 54.33%, 84.99%, and 90.49%, respectively. The removal rates of Pb(II) by MC, MCM, and MCAA are 61.54%, 91.32%, and 95.74%, respectively. MCAA shows good flocculation performance in composite heavy metal-simulated wastewater. The magnetic carboxymethyl chitosan-based flocculant shows excellent flocculation performance in removing soluble heavy metals. This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove heavy metals in wastewater.


Assuntos
Quitosana , Metais Pesados , Floculação , Fenômenos Magnéticos , Águas Residuárias
19.
J Neurosci Res ; 98(6): 1188-1197, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820502

RESUMO

Over the past decade, many studies have focused on clarifying the roles of different N-methyl-d-aspartate (NMDA) receptor subunits in cerebral ischemia, hoping to develop subunit-selective drugs. Recently, more attention was given to studying the role of GluN2C in ischemia damage, which may lead to the development of new NMDA receptor antagonists for cerebral ischemia. Results showed that GluN2C inhibition or knockout can effectively alleviate the ischemic injury caused by middle cerebral artery occlusion and, contrarily, can aggravate the damage to hippocampal CA1 circuit caused by transient global cerebral ischemia. These results indicate the complicated roles of GluN2C in cerebral ischemia. In this minireview, we focus on these findings, describe the roles of GluN2C from different cell origins in ischemic damage, and explain the above inconsistent experimental results.


Assuntos
Astrócitos/metabolismo , Isquemia Encefálica/metabolismo , Encéfalo/metabolismo , Neurônios/metabolismo , Oligodendroglia/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Humanos
20.
Drug Dev Ind Pharm ; 46(7): 1177-1184, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32538184

RESUMO

Most of the mesoporous chiral mesoporous silica (CMS) was synthesized by the chiral surfactant-directing method. In this study, a facile method was designed to synthesize CMS. In this method, achiral amphiphile was used as templating agents, and dilute ammonia solution was applied to induce the chirality of the CMS. Meanwhile, its morphology can be controlled by changing the concentration of the aqueous ammonia solution. The obtained CMS was characterized by dynamic light scattering (DLS), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The results showed that all of the CMS possessed highly ordered mesostructures, and as the concentration of ammonia decreases, the chirality of the CMS becomes more obvious. Water-insoluble drug curcumin (Cur) was used as a model drug. The characteristics of CMS before and after drug loading were further detected by Fourier transform infrared spectrometer (FT-IR), N2 adsorption-desorption and differential scanning calorimetry (DSC). The result showed that Cur was successfully loaded inside the pores of the CMS and remained an amorphous state due to steric inhibition. Additionally, CMS could significantly increase the release rate of Cur under different pH conditions.


Assuntos
Dióxido de Silício , Água , Portadores de Fármacos , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
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