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1.
J Neuroinflammation ; 19(1): 213, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36050772

RESUMO

BACKGROUND: Chronic kidney disease (CKD), characterized as renal dysfunction, is regarded as a major public health problem which carries a high risk of cardiovascular diseases. The purpose of this study is to evaluate the functional significance of Drp1 in hypercalcemia-associated neuronal damage following CKD and the associated mechanism. METHODS: Initially, the CKD mouse models were established. Next, RT-qPCR and Western blot analysis were performed to measure expression of Fis1 and Drp1 in CKD. Chromatin immunoprecipitation (ChIP) assay and dual-luciferase reporter gene assay were utilized to explore the relationship among Drp1, HIF-1α, EZH2, and ROS with primary cortical neurons isolated from neonatal mice. Next, CKD mice were subjected to calcitonin treatment or manipulation with adenovirus expressing sh-Drp1, so as to explore the effects of Drp1 on hypercalcemia-induced neuronal injury in CKD. TUNEL assay and immunofluorescence staining were performed to detect apoptosis and NeuN-positive cells (neurons) in prefrontal cortical tissues of CKD mice. RESULTS: It was found that hypercalcemia could induce neuronal injury in CKD mice. An increase of Fis1 and Drp1 expression in cerebral cortex of CKD mice correlated with mitochondrial fragmentation. Calcitonin suppressed Drp1/Fis1-mediated mitochondrial fragmentation to attenuate hypercalcemia-induced neuronal injury after CKD. Additionally, Drp1 could increase EZH2 expression through the binding of HIF-1α to EZH2 promoter via elevating ROS generation. Furthermore, Drp1 knockdown inhibited hypercalcemia-induced neuronal injury in CKD while overexpression of EZH2 could reverse this effect in vivo. CONCLUSION: Taken together, the key findings of the current study demonstrate the promotive role of Drp1 in mitochondrial fragmentation which contributes to hypercalcemia-induced neuronal injury in CKD.


Assuntos
Dinaminas/metabolismo , Hipercalcemia , Mitocôndrias , Insuficiência Renal Crônica , Animais , Apoptose , Calcitonina/metabolismo , Calcitonina/farmacologia , Modelos Animais de Doenças , Dinaminas/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Hipercalcemia/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Mitocôndrias/metabolismo , Neurônios/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Insuficiência Renal Crônica/metabolismo
2.
J Mol Recognit ; 34(4): e2880, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33166010

RESUMO

In this work, seven acrylonitrile derivatives were selected as potential inhibitors of fat and obesity-related proteins (FTO) by the aid of fluorescence spectroscopy, ultraviolet visible spectroscopy, molecular docking, and cytotoxicity methods. Results show that the interaction between 3-amino-2-(4-chlorophenyl)-3-phenylacrylonitrile (1a) and FTO was the strongest among these derivatives. Thermodynamic analysis and molecular modeling show that the main force between 1a and FTO is hydrophobic interaction. The cytotoxicity test showed that the IC50 value of 1a was 46.64 µmol/L, which indicated 1a had the smallest IC50 value and had the best inhibitory effect on the proliferation of leukemia K562 cells among the seven derivatives. Both our previous results and this work show that chlorine atoms play important role in the binding of small molecules and FTO. This work brings new information for the study of FTO inhibitors.


Assuntos
Acrilonitrila/química , Acrilonitrila/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/química , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Cloro/química , Acrilonitrila/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Fluorescência , Humanos , Células K562 , Modelos Moleculares , Espectrometria de Fluorescência/métodos , Espectrofotometria Ultravioleta , Termodinâmica
3.
Opt Express ; 29(8): 12195-12205, 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33984984

RESUMO

A novel laser-induced thermoelastic spectroscopy (LITES) sensor based on a polymer-coated quartz tuning fork (QTF) is reported. Two types of polymer films with different thicknesses are deposited on commercially available QTF to improve the conversion efficiency of laser energy deposition into vibration. CO2 was selected as the target analyte for validation measurements. The experimental results indicate that by introducing a polymer coating, a maximum gain factor of 3.46 and 3.21 is attained for the signal amplitude and signal-to-noise ratio (SNR), respectively, when compared to traditional LITES that using only a bare QTF. A minimum detectable concentration of 0.181% can be obtained, corresponding to a normalized noise equivalent absorption coefficient (NNEA) of 1.74×10-11 cm-1·W·Hz-1/2, and the measurement precision is approximately 0.06% with an averaging time of 200 s. Here, we show what we believe is the first demonstration of polymer coated QTF for LITES sensing, compared with custom QTF, the design has the virtues of lower cost, simple and easy-to-operate, is a promising new strategy for sensitive trace gas analysis.

4.
Opt Express ; 29(13): 20190-20204, 2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34266113

RESUMO

Sensitive and broadband infrared sensors are required for security and medical applications, as few can rapidly and sensitively detect infrared without uncooled devices. Here, we report a wideband optical-detection strategy based on the thermoelastic effect of a coating-enhanced quartz tuning fork (QTF) and study the feasibility of using an atomic force probe operating in contact mode to monitor the vibration. Graphene oxide (GO) and polydimethylsiloxane (PDMS) coating were applied on the QTF's surface to improve the light absorption and the thermal-mechanical conversion efficiency. Experimental results showed that the bi-layer coatings yielded a maximum gain factor of 8 in response amplitude and signal-to-noise ratio (SNR) than that of a bare QTF, respectively. Lasers with wavelengths of 1512 nm and 10.6 µm were used as the typical representative light source to test the photoresponse of the QTF detector. The device displays a broadband photoresponse covering the near-infrared to mid-infrared range at room temperature, high performance with the maximum photoresponsivity of 85.76 V·mW-1, and 1σ detection limit of 0.056 µW; the lowest noise equivalent power (NEP) of 1.35 nW·Hz-1/2 and 43.9 ms response speed is also achieved. The preparation process of detector is simple and easy to implement; the resulting device exhibits high responsivity and wide wavelength response ranging at least from 1512 to 10600 nm, compared with custom QTF; and the surface coating strategy potentially enables the construction of a new class of low-cost photodetection sensors operated at room temperature.

5.
BMC Infect Dis ; 19(1): 19, 2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30616531

RESUMO

BACKGROUND: Hand, foot and mouth disease (HFMD) is an infectious disease caused by enteroviruses that has a severely impair for those high incidence countries such as China.The current study aimed to investigate the epidemic pattern of HFMD by time and region in Northwestern China. METHODS: All reported HFMD cases from 2008 to 2015 were collected from local Disease Control and Prevention.The HFMD was diagnosed in accordance with the guidebook provided by the National Health and Family Planning Commission of the People's Republic of China. RESULTS: A total of 154,869 cases of probable HFMD were reported. The overall incidence of HFMD has been increased from 91.68 per 100/000 in 2008 to 335.64 per 100/000 in 2015.The case mortality is decreased from 0.014 per100/000 to 0.011 per 100/000 during the time period. Most HFMD (93.82%) occurred in children younger than 5 years. The seasonal peak of HFMD infections occurred in April-July and September-November and Central regions of Xi'an city were the major locations of the clusters (incidence rate 245.75/100,000; relative risk 1.19, P < 0.01). EVA71 was the predominant enterovirus serotype, accounting for 50.0% of all reported HFMD cases since 2011.The most susceptible group infected by HFMD was children younger than 5 years, especially boys. CONCLUSIONS: Incidence of HFMD has been increasing in the past few years, however, the case fatality is decreasing. Season and region shall be considered as influence factors in the prevention of HFMD.


Assuntos
Doença de Mão, Pé e Boca/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , China/epidemiologia , Cidades , Enterovirus Humano A/classificação , Enterovirus Humano A/patogenicidade , Epidemias , Feminino , Doença de Mão, Pé e Boca/mortalidade , Doença de Mão, Pé e Boca/virologia , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Mortalidade , Estações do Ano , Sorogrupo
6.
Int J Mol Sci ; 16(1): 1008-29, 2015 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-25569083

RESUMO

Here we describe a chemical biology approach for elucidating potential toxicity mechanisms for thrombosis-related side effects. This work takes advantage of a large chemical biology data set comprising the effects of known, well-characterized reference agents on the cell surface levels of tissue factor (TF) in a primary human endothelial cell-based model of vascular inflammation, the BioMAP® 3C system. In previous work with the Environmental Protection Agency (EPA) for the ToxCast™ program, aryl hydrocarbon receptor (AhR) agonists and estrogen receptor (ER) antagonists were found to share an usual activity, that of increasing TF levels in this system. Since human exposure to compounds in both chemical classes is associated with increased incidence of thrombosis-related side effects, we expanded this analysis with a large number of well-characterized reference compounds in order to better understand the underlying mechanisms. As a result, mechanisms for increasing (AhR, histamine H1 receptor, histone deacetylase or HDAC, hsp90, nuclear factor kappa B or NFκB, MEK, oncostatin M receptor, Jak kinase, and p38 MAPK) and decreasing (vacuolar ATPase or V-ATPase) and mTOR) TF expression levels were uncovered. These data identify the nutrient, lipid, bacterial, and hypoxia sensing functions of autophagy as potential key regulatory points controlling cell surface TF levels in endothelial cells and support the mechanistic hypothesis that these functions are associated with thrombosis-related side effects in vivo.


Assuntos
Células Endoteliais/efeitos dos fármacos , Modelos Biológicos , Compostos Orgânicos/toxicidade , Trombose/etiologia , Autofagia , Biomarcadores/metabolismo , Células Cultivadas , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Tromboplastina/metabolismo
7.
Front Physiol ; 15: 1346579, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660535

RESUMO

Glycerophosphocholine (GPC) is a water-soluble small molecule found naturally in humans and foods such as milk and soybeans. It can activate the IIS pathway by regulating the expression of daf-2, ins-18 and daf-16 genes, sek-1 and skn-1 genes of MAPK pathway, sod-3, ctl-1, gst-4 and other antioxidant genes. GPC can relieve symptoms related to aging in organisms. The aim of this study was to probe the effects of GPC on the longevity and stress resistance of the entomopathogenic nematode (EPN) Steinernema kraussei 0657L strain. The results showed that the lifespan of S. kraussei 0657L was significantly prolonged by 50 mM GPC treatment, which was 54.55% longer than that of the control (0 mM GPC). GPC significantly inhibited reactive oxygen species (ROS) and lipofuscin accumulation, but the body size and fecundity of S. kraussei 0657L had little changed. At the same time, the longevity of S. kraussei 0657L exposed to heat shock and UV-B radiation was significantly prolonged than that with no external stress. GPC supplementation increased the activity of antioxidant enzymes and corresponding gene expression. Under treatment with 50 mM GPC, the activities of superoxide dismutase and catalase were increased by 1.90- and 4.13-fold, respectively, the expression of the sod-3 and ctl-1 genes was increased by 3.60- and 0.60-fold, respectively, and harmful reactive oxygen species were removed. In addition, the expression levels of the ins-18, skn-1, sek-1 and gst-4 genes related to the insulin/IGF-1 signaling pathway were upregulated 1.04-, 1.84-, 2.21- and 1.24-fold, respectively. These results indicate that GPC is mainly involved in the lifespan regulation of S. kraussei 0657L and plays an important role in resistance to external stress by activating the insulin/IGF-1 signaling pathway and downstream PI3K/MAPK kinase, creating a new idea for improving the commercial efficacy of S. kraussei. It also laid a theoretical foundation for its further efficient development and utilization in the field of biological control.

8.
Cell Signal ; 116: 111063, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38242267

RESUMO

Chronic kidney disease (CKD) often culminates in hypercalcemia, instigating severe neurological injuries that are not yet fully understood. This study unveils a mechanism, where GSK343 ameliorates CKD-induced neural damage in mice by modulating macrophage polarization through the EZH2/MST1/YAP1 signaling axis. Specifically, GSK343 downregulated the expression of histone methyltransferase EZH2 and upregulated MST1, which suppressed YAP1, promoting M2 macrophage polarization and thereby, alleviating neural injury in hypercalcemia arising from renal failure. This molecular pathway introduced herein not only sheds light on the cellular machinations behind CKD-induced neurological harm but also paves the way for potential therapeutic interventions targeting the identified axis, especially considering the M2 macrophage polarization as a potential strategy to mitigate hypercalcemia-induced neural injuries.


Assuntos
Hipercalcemia , Piridonas , Insuficiência Renal Crônica , Camundongos , Animais , Macrófagos , Indazóis/farmacologia , Insuficiência Renal Crônica/complicações
9.
Environ Pollut ; 306: 119349, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35487467

RESUMO

Increasing rates of commercialization and industrialization have led to the comprehensive evaluation of toxic effects of microplastics on crop plants. However, research on the impact of functionalized polystyrene nanoplastics on the toxicity of heavy metals remains limited. This study investigated the effects of polystyrene, carboxy-modified polystyrene, and amino-modified polystyrene on lead (Pb) toxicity in dandelion seedlings. The results showed that carboxy -modified polystyrene with a negative charge absorbed more Pb2+ than polystyrene and amino-modified polystyrene, and their maximum adsorption amounts were 5.328, 0.247, and 0.153 µg g-1, respectively. The hydroponic experiment demonstrated that single amino-modified polystyrene was more toxic to dandelion seedlings than polystyrene and carboxy-modified polystyrene. The presence of Pb2+ was found to increase antioxidant enzymes (superoxide dismutase and catalase) and non-antioxidant enzymes (glutathione and ascorbic acid) activities in response to excessive reactive oxygen species in dandelion leaves and roots treated with polystyrene and carboxy-modified polystyrene, while it did not change much when amino-modified polystyrene was added. Interestingly, compared with single Pb2+, the addition of amino-modified polystyrene with positive charges induced an obvious decrease in the above parameters; however, they declined slightly in the treatments with polystyrene and carboxy-modified polystyrene despite a stronger adsorption capacity for Pb2+. Similarly, the bioactive compounds, including flavonoids, polyphenols, and polysaccharides in dandelion, showed a scavenging effect on O2- and H2O2, thereby inhibiting the accumulation and reducing medicinal properties. This study found that the effects of microplastics on the uptake, distribution, and toxicity of heavy metals depended on the nanoparticle surface charge.


Assuntos
Metais Pesados , Taraxacum , Peróxido de Hidrogênio/farmacologia , Chumbo/toxicidade , Metais Pesados/farmacologia , Microplásticos , Plásticos/farmacologia , Poliestirenos/toxicidade , Plântula
10.
J Pharm Biomed Anal ; 207: 114426, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34689062

RESUMO

Alcoholism is a severe threat to public health, and there are no adequate treatments for alcoholic liver disease. The aim of this study was to identify bioactive peptides derived from natural proteins that prevent acute alcohol-induced liver injury. We identified a peptide with the sequence Gly-Leu-hydroxyproline-Gly-Glu-Arg (GLpGER) from the hydrolysate of crucian carp swim bladder using size-exclusion chromatography and reversed-phase chromatography. The in vitro EC50 value of GLpGER to activate alcohol dehydrogenase (ADH) was 137.9 ± 9 µM. Molecular docking experiments indicated that the mechanism by which GLpGER activates ADH may be related to the formation of stable complexes with ADH active pockets through hydrogen bonding, and electrostatic and hydrophobic interactions. Oral administration of GLpGER one hour before acute alcohol ingestion significantly increased alcohol metabolism, manifesting as reduced incidence of the loss of righting reflex, increased alcohol tolerance time, shortened sobering time, and decreased blood alcohol concentration level. GLpGER restored liver ADH activity, maintained the typical morphology of hepatocytes, and reduced serum levels of alanine aminotransferase and aspartate aminotransferase. These findings suggest that GLpGER might reduce acute alcohol-induced liver injury and may have the potential to be developed as an anti-inebriation ingredient.


Assuntos
Carpas , Doença Hepática Crônica Induzida por Substâncias e Drogas , Álcool Desidrogenase , Animais , Concentração Alcoólica no Sangue , Etanol , Fígado , Camundongos , Simulação de Acoplamento Molecular , Peptídeos , Bexiga Urinária
11.
Biomed Pharmacother ; 156: 113947, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36411661

RESUMO

BACKGROUND: Sodium glucose cotransporter 2 (SGLT2) inhibitors originally developed for the treatment of type 2 diabetes are clinically very effective drugs halting chronic kidney disease progression. The underlying mechanisms are, however, not fully understood. METHODS: We generated single-cell transcriptomes of kidneys from rats with 5/6 nephrectomy before and after SGLT2 inhibitors treatment by single-cell RNA sequencing. FINDINGS: Empagliflozin treatment decreased BUN, creatinine and urinary albumin excretion compared to placebo by 39.8%, 34.1%, and 55%, respectively (p < 0.01 in all cases). Renal interstitial fibrosis and glomerulosclerosis was likewise decreased by 51% and 66.8%; respectively (p < 0.05 in all cases). 14 distinct kidney cell clusters could be identified by scRNA-seq. The polarization of M2 macrophages from state 1 (CD206-CD68- M2 macrophages) to state 5 (CD206+CD68+ M2 macrophages) was the main pro-fibrotic process, as CD206+CD68+ M2 macrophages highly expressed fibrosis-promoting genes and can convert into fibrocytes. Empagliflozin remarkably inhibited the expression of fibrosis-promoting (IFG1 and TREM2) and polarization-associated genes (GPNMB, LGALS3, PRDX5, and CTSB) in CD206+CD68+ M2 macrophages and attenuated inflammatory signals from CD8+ effector T cells. The inhibitory effect of empagliflozin on CD206+CD68+ M2 macrophages polarization was mainly achieved by affecting mitophagy and mTOR pathways. INTERPRETATION: We propose that the beneficial effects of empagliflozin on kidney function and morphology in 5/6 nephrectomyiced rats with established CKD are at least partially due to an inhibition of CD206+CD68+ M2 macrophage polarization by targeting mTOR and mitophagy pathways and attenuating inflammatory signals from CD8+ effector T cells. FUNDINGS: A full list of funding bodies that contributed to this study can be found in the Acknowledgements section.


Assuntos
Diabetes Mellitus Tipo 2 , Insuficiência Renal Crônica , Ratos , Animais , Ativação de Macrófagos , Diabetes Mellitus Tipo 2/patologia , Fibrose , Rim/patologia , Insuficiência Renal Crônica/tratamento farmacológico , Insuficiência Renal Crônica/patologia , Nefrectomia , Serina-Treonina Quinases TOR , Glicoproteínas de Membrana
12.
Future Med Chem ; 13(17): 1475-1489, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34240624

RESUMO

Studies have shown that the FTO gene is closely related to obesity and weight gain in humans. FTO is an N6-methyladenosine demethylase and is linked to an increased risk of obesity and a variety of diseases, such as acute myeloid leukemia, type 2 diabetes, breast cancer, glioblastoma and cervical squamous cell carcinoma. In light of the significant role of FTO, the development of small-molecule inhibitors targeting the FTO protein provides not only a powerful tool for grasping the active site of FTO but also a theoretical basis for the design and synthesis of drugs targeting the FTO protein. This review focuses on the structural characteristics of FTO inhibitors and discusses the occurrence of obesity and cancer caused by FTO gene overexpression.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato/antagonistas & inibidores , Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Neoplasias/tratamento farmacológico , Bibliotecas de Moléculas Pequenas/farmacologia , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Antineoplásicos/química , Inibidores Enzimáticos/química , Humanos , Neoplasias/metabolismo , Bibliotecas de Moléculas Pequenas/química
13.
J Hazard Mater ; 411: 125194, 2021 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-33858121

RESUMO

The poor water stability of metal-organic frameworks (MOFs) significantly hindered their catalytic application in advanced oxidation system. A protective outer layer was an effective strategy to solve this problem. However, the commonly used coating techniques are too complicated or too difficult to accurately control, thus, the applicability was relatively low. In this study, a water stable MOF core-SiO2 shell nanomaterial (Fe-MOF-74@SiO2) was synthesized by a facile hydrothermal method, and applied to activate persulfate (PS) for dimethyl phthalate (DMP) degradation. The catalyst water stability and DMP degradation in the system were investigated, suggesting that the SiO2-coated catalyst was more stable and exhibited higher DMP degradation efficiency over the pure MOF. It was found that pH had negligible effects on Fe-MOF-74@SiO2 + PS system, while, higher temperature facilitated the degradation of DMP. The activation mechanism was studied by quenching experiments combined with electron paramagnetic resonance, indicating that SO4⋅- played a major role in the activation of PS with Fe-MOF-74@SiO2 for DMP removal, while ⋅OH also involved in the catalytic process. Finally, possible DMP degradation pathways were proposed. These findings indicated that the core-shell structured Fe-MOF-74@SiO2 showed promise for DMP degradation by PS advanced oxidation system.

14.
Water Res ; 203: 117541, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-34416650

RESUMO

Efficient removal of low-concentration refractory pollutants is a crucial problem to ensuring water safety. The use of heterogeneous catalysis of molecular imprinting technology combined with traditional catalysts is a promising method to improve removal efficiency. Presently, the research into molecular imprinting targeting catalysts focuses mainly on material preparation and performance optimization. However, more researchers are investigating other applications of imprinting materials. This review provides recent progress in photocatalyst preparation, electrocatalyst, and Fenton-like catalysts synthesized by molecular imprinting. The principle and control points of target catalysts prepared by precipitation polymerization (PP) and surface molecular imprinting (S-MIP) are introduced. Also, the application of imprinted catalysts in targeted degradation of drugs, pesticides, environmental hormones, and other refractory pollutants is summarized. In addition, the reusability and stability of imprinted catalyst in water treatment are discussed, and the possible ecotoxicity risk is analyzed. Finally, we appraised the prospects, challenges, and opportunities of imprinted catalysts in the advanced oxidation process. This paper provides a reference for the targeted degradation of refractory pollutants and the preparation of targeted catalysts.


Assuntos
Impressão Molecular , Poluentes Químicos da Água , Purificação da Água , Catálise , Águas Residuárias , Poluentes Químicos da Água/análise
15.
Chemosphere ; 270: 128620, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33109356

RESUMO

Adsorptive removal of dimethyl phthalate (DMP) in water combined with advanced oxidation processes (AOPs) has attracted interest. In this work, the adsorptive and catalytic properties of an Fe-based metal-organic framework (Fe-MOF-74) have been improved by molecular imprinting technique. The adsorption behaviors have been evaluated by the Freundlich and pseudo-second-order model. The results have shown that selective adsorption ability of the material for DMP was highly enhanced and chemisorption was dominating. A 1.5-fold increase in catalytic rate after being modified by molecular imprinting indicated that the selective adsorption is crucial. In the synergy of adsorption and catalysis, DMP was first specifically adsorbed on the surface of the material by hydrogen bonds and electrostatic interactions. Then, hydroxyl radicals and sulfate radicals, which were both generated via activation of persulfate (PS), catalytically oxidized DMP. The degradation rate can rapidly reach around 90% in 30 min and three possible degradation pathways were proposed. The molecular imprinting modified catalyst can be used for DMP effective degradation in water.


Assuntos
Impressão Molecular , Ácidos Ftálicos , Poluentes Químicos da Água , Adsorção , Catálise , Oxirredução
16.
Front Plant Sci ; 11: 241, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210999

RESUMO

Cyanobacteria have evolved various strategies to sense and adapt to biotic and abiotic stresses including active movement. Motility in cyanobacteria utilizing the type IV pili (TFP) is useful to cope with changing environmental conditions. The model cyanobacterium Synechocystis sp. PCC 6803 (hereafter named Synechocystis) exhibits motility via TFP called thick pili, and uses it to seek out favorable light/nutrition or escape from unfavorable conditions. Recently, a number of studies on Synechocystis thick pili have been undertaken. Molecular approaches support the role of the pilin in motility, cell adhesion, metal utilization, and natural competence in Synechocystis. This review summarizes the most recent studies on the function of thick pili as well as their formation and regulation in this cyanobacterium.

17.
J Hazard Mater ; 398: 123024, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-32768834

RESUMO

In this work, ZSM-5-(C@Fe), as a peroxymonosulfate (PMS) heterogeneous activator, was synthesized, characterized, and evaluated for activating PMS to degrade ciprofloxacin (CIP) in wastewater. Zeolite Socony Mobil-5 (ZSM-5) was utilized to enhance structural stability and provided a scaffold to graft Fe doping C nanocomposites activator. Pyrolytic metal-organic frameworks (MOFs) can use crystal structure to construct stable carbon-encapsulated Fe nanocomposites. The formation of C-O-Si, C-O-Al and C-Fe was the key to the stability of catalysts. Fe doping in ZSM-5-(C@Fe) formed non-radical degradation pathway was the key to improve the degradation efficiency. The experimental data indicated ZSM-5-(C@Fe) could completely remove 20 mg L-1 CIP within 15 min and achieve good results in the experiments of treating actual wastewater, which could reduce 40% COD of the paper mill aerobic pond effluent. The Fukui function calculation and UHPL C-H RMS/MS analysis elucidated that the 1O2-dominated electrophilic reaction and the ZSM-5-(C@Fe) complex PMS-dominated nucleophilic reaction were the main pathways for CIP degradation and the radical degradation pathway (·OH and SO4-˙) plays auxiliary role. In addition, two new degradation pathways of the N29 and C27 in quinolone ring and the N22 in piperazine ring were discovered. This finding had important implications for the removal of N from organic pollutants.


Assuntos
Ciprofloxacina , Zeolitas , Peróxidos , Águas Residuárias
18.
Chemosphere ; 240: 124875, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31541899

RESUMO

Adsorptive removal of phthalate esters from wastewater combined with their persulfate (PS) catalytic degradation has attracted the attention of many researchers. In this study, the adsorptive and catalytic properties of an MIL100 material obtained by a green synthetic route have been optimized by a surface molecular imprinting technique. Results have shown that there are two steps in the molecular imprinting process. A polymerization is first carried out in the internal channels of the material and the imprinting layer is then formed on the surface. The relative proportions of the starting materials for the synthesis have been optimized through the design of a three-dimensional response surface. The amount of pollutant adsorbed was increased fourfold after surface imprinting, reaching 13.6 mg g-1. The homogeneity of the recognition sites has been evaluated by dynamics calculations and the Freundlich equation. The selective adsorption ability of the material for diethyl phthalate was improved, and the process involved chemical adsorption. The catalytic properties of the material after imprinting were increased about 1.5-fold, indicating that selective adsorption is important. Such molecularly imprinted polymers may potentially serve as good functional materials for the removal of phthalate esters from wastewater.


Assuntos
Impressão Molecular/métodos , Ácidos Ftálicos/química , Águas Residuárias/química , Polímeros/química
19.
J Hazard Mater ; 377: 163-171, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31158585

RESUMO

In the advanced oxidation system (AOPs) of persulfate (PS) activated by iron-based metal-organic frameworks (MOFs), aim at solving the problem on the treatment difficulty of wastewater with low concentration persistent organic pollutants (POPs), a new type of ferrous metal-organic frameworks (Fe(Ⅱ)-MOFs) with stronger coordinatively unsaturated metal sites (CUS) was successfully synthesized by different methods. The catalytic performance of Fe(Ⅱ)-MOFs was were obtained by the experiment of degrading dibutyl phthalate (DBP) through persulfate activation. It was found that the degradation efficiency of 0.018 mmol L-1 DBP was 86.73% under the conditions of 0.40 g L-1 and 2.70 mmol L-1 persulfate at a wide pH range. At the same time, the crystal structure and surface morphology of Fe(Ⅱ)-MOFs did not change significantly after reaction and it could still maintain the removal rate of 75.44% of the target pollutants in the fifth cycle. Furthermore, in the consideration of iron valence state of MOFs before and after reaction, and combined with the analysis of electrochemical properties, the possible mechanism of PS activation was proposed, namely the metastable electron layer inside ferrous ions produced the internal power to accelerate the electron transfer in CUS, leading to improve the activity of the catalyst.

20.
Prev Vet Med ; 162: 151-159, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30621894

RESUMO

BACKGROUND: Live poultry market (LPM) workers are at high risk of infection with avian influenza virus due to frequent occupational exposure to poultry. This study aims to assess the knowledge, attitude and preventive practice regarding avian influenza among LPM workers in Chongqing, the largest municipality directly under the central government of China. METHODS: 216 LPM workers were recruited by two-stage cluster sampling and interviewed face-to-face using a structured questionnaire. Hierarchical logistic regression analysis was performed to explore factors associated with preventive practices against avian influenza and views on government control measures. RESULTS: Nearly half of respondents failed to recognize contact with sick birds or excrement as a risk of infection. Less than half the respondents perceived themselves to have a personal susceptibility to be infected or would like to enhance personal protection. Respondents did not pay sufficient attention to wearing preventive clothing such as gloves (43.1%), aprons/garments (33.3%) and face masks (26.9%) when handling live poultry. Few respondents were supportive to market control measures such as a ban on birds' overnight storage (26.8%) or a regular rest day (32.4%). Being older, being more highly educated, having worked longer with poultry, having better knowledge, having more access to information, and perceiving more personal susceptibility to the disease were positively associated with preventive practices. Having higher personal income, longer engagement with poultry work, better knowledge, more awareness of personal protection were positively associated with agreement with government control measures. CONCLUSIONS: LPM workers in Chongqing showed low level of knowledge, weak perception of susceptibility to avian influenza and inadequate preventive behaviors. Health education campaigns need to better target the knowledge on transmission routes and potential outbreak threat of avian influenza. More attention should be paid to LPM workers who are younger, less educated, with shorter occupational years and lower personal income.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Influenza Aviária/prevenção & controle , Influenza Humana/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle , Adulto , Animais , China , Humanos , Influenza Humana/psicologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/prevenção & controle , Doenças Profissionais/psicologia , Aves Domésticas/virologia , Roupa de Proteção , Inquéritos e Questionários
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