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1.
Environ Res ; 241: 117653, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37980982

RESUMO

When confronted with wastewater that is characterized by complex composition, stable molecular structure, and high concentration, relying solely on photocatalytic technology proves inadequate in achieving satisfactory degradation results. Therefore, the integration of other highly efficient degradation techniques has emerged as a viable approach to address this challenge. Herein, a novel strategy was employed whereby the exfoliated g-C3N4 nanosheets (CNs) with exceptional photocatalytic performance, were intimately combined with porous rod-shaped cobalt ferrite (CFO) through a co-calcination process to form the composite CFO/CNs, which exhibited remarkable efficacy in the degradation of various organic pollutants through the combination of photocatalysis and Fenton-like process synergistically, exemplified by the representative case of tetracycline hydrochloride (TCH, 200 mL, 50 mg/L). Specifically, under 1 mM of peroxymonosulfate (PMS) and illumination conditions, 50 mg of 1CFO/9CNs achieved a TCH removal ratio of ∼90% after 60 min of treatment. Furthermore, this work comprehensively investigated the influence of various factors, including catalyst and PMS dosages, solution pH, and the presence of anions and humate, on the degradation efficiency of pollutants. Besides, quenching experiments and EPR tests confirmed the establishment of an S-scheme heterojunction between CNs and CFO, which facilitated the effective spatial separation of photoexcited charge carriers and preserved the potent redox potential of photogenerated electrons and holes. This work offers a valuable reference for the integration of photocatalysis with the PMS-based Fenton-like process.


Assuntos
Elétrons , Poluentes Ambientais , Porosidade , Iluminação
2.
Small ; : e2308068, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38054769

RESUMO

Developing robust electrodes with high catalytic performance is a key step for expanding practical HER (hydrogen evolution reaction) applications. This paper reports on novel porous Mo2 C-based ceramics with oriented finger-like holes directly used as self-supported HER electrodes. Due to the suitable MoO3 sintering additive, high-strength (55 ± 6 MPa) ceramic substrates and a highly active catalytic layer are produced in one step. The in situ reaction between MoO3 and Mo2 C enabled the introduction of O in the Mo2 C crystal lattice and the formation of Mo2 C(O)/MoO2 heterostructures. The optimal Mo2 C-based electrode displayed an overpotential of 333 and 212 mV at 70 °C under a high current intensity of 1500 mA cm-2 in 0.5 m H2 SO4 and 1.0 m KOH, respectively, which are markedly better than the performance of Pt wire electrode; furthermore, its price is three orders of magnitude lower than Pt. The chronopotentiometric curves recorded in the 50 - 1500 mA cm-2 range, confirmed its excellent long-term stability in acidic and alkaline media for more than 260 h. Density functional theory (DFT) calculations showed that the Mo2 C(O)/MoO2 heterostructures has an optimum electronic structure with appropriate *H adsorption-free energy in an acidic medium and minimum water dissociation energy barrier in an alkaline medium.

3.
Environ Sci Pollut Res Int ; 30(57): 119804-119813, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37930569

RESUMO

Black soldier fly larvae (BSFL) bioconversion system is emerging as an effective approach for organic waste pollution treatment. Co-digestion of different organic matters with BSFL can be an effective way to realize the innovative biowaste circular economy. In this study, organic waste mixture of chicken manure and sewage sludge was chosen as substrate for BSFL growth. The bacterial biodiversity and nutrients quality of BSFL residue were evaluated through gene sequencing and other characterizations to confirm their application potential as biofertilizers. The dominant bacteria in BSFL residue were Firmicutes (75.39%) at phylum level, Bacilli (71.61%) at class level and Pseudogracilibacillus (11.08%) at genus level. Antibiotic resistance genes (ARGs) were used to assess the harmlessness of BSFL residue. After BSFL treatment, 36.2% decrease in ARGs was observed. Taking nutrients quality into consideration, dissolved organic carbon, dissolved nitrogen, available phosphorous, and available potassium significantly increased in the co-digestion system. These results demonstrated that co-digestion of chicken manure and excess sludge in BSFL bioconversion system could improve the nutrients quality of residues. However, removal of ARGs in the bioconversion process should be further explored to eliminate environmental concerns associated with application of BSFL residue as biofertilizers.


Assuntos
Dípteros , Esgotos , Animais , Larva , Esterco , Galinhas , Nutrientes , Bactérias , Digestão
4.
Gynecol Endocrinol ; 39(1): 2228917, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37406659

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a complicated gynecological endocrine disease that occurs in women of childbearing age. Protocatechuic acid is a phenol-rich compound derived from herbs and owns vital functions in numerous diseases. Howbeit, protocatechuic acid's impact on PCOS is unknown. METHODS: A combination of in vivo and in vitro models was examined in this study. C57BL/6 mice were injected subcutaneously daily with dehydroepiandrosterone to establish a PCOS mouse model, and protocatechuic acid was intraperitoneally injected into PCOS mice. Granulosa cells of PCOS ovaries were also isolated. The function of protocatechuic acid was appraised using enzyme-linked immunosorbent assay, hematoxylin-eosin staining, reactive oxygen species (ROS) and LC3 levels analysis, flow cytometry, quantitative real-time PCR, and western blot. Meanwhile, the mechanism of protocatechuic acid was assessed with a series of molecular experiments. RESULTS: Protocatechuic acid owned no apparent toxic effect on mice. Functionally, protocatechuic acid owned a function of mitigating PCOS in vivo. Meanwhile, protocatechuic acid repressed ROS, autophagy, and apoptosis of PCOS ovarian granulosa cells in vitro. Mechanistically, rescue assays elucidated that the protective function of protocatechuic acid against PCOS was interrelated to the activation of the PI3K/AKT/mTOR axis. CONCLUSION: Protocatechuic acid alleviated PCOS symptoms in mice through PI3K signaling in granulosa cells to reduce ROS levels and apoptosis.


Assuntos
Síndrome do Ovário Policístico , Humanos , Camundongos , Feminino , Animais , Síndrome do Ovário Policístico/tratamento farmacológico , Fosfatidilinositol 3-Quinases , Espécies Reativas de Oxigênio , Camundongos Endogâmicos C57BL , Células da Granulosa , Apoptose
5.
Membranes (Basel) ; 12(8)2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-36005661

RESUMO

This paper presented an innovative method for fabrication of a porous Al2O3/CaAl12O19 ceramic membrane by combining emulsion method, cement curing and tape-casting technologies. The ceramic membrane featured a smooth surface and a porous internal structure. By adjusting the oil-water volume ratio from 1:1 to 4:1, the porosity of the samples increases from 45.6 to 67.3%, density decreases from 2.07 to 1.32 g/cm3 and bending strength decreases from 64.3 ± 1.2 to 31.7 ± 0.6 MPa. More significantly, the membranes showed great gas permeability (1.2 × 107-2.3 × 107 Lm-2 h-1 bar-1), opening up a wide range of applications in the field of gas filtration processes.

6.
Reprod Biol ; 22(3): 100671, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35905692

RESUMO

Oxidative stress plays a central role in polycystic ovary syndrome (PCOS). Catalpol (CAT) is the active ingredient of Rehmannia glutinosa Libosch which has therapeutic effect on PCOS. However, little is known about the mechanism of CAT in PCOS. PCOS rats were induced by subcutaneous injection of dehydroepiandrosteronec for four weeks and then were treated with CAT (50 mg/kg) or carboxyl methyl cellulose (the solvent of CAT) or normal saline for another 4 weeks. Histopathological observation of ovarian tissues, the levels of testosterone, estradiol and progesterone in rat plasma samples, the oxidative stress related-indexes and the expressions of NF-κB pathway-related proteins were determined. KGN cell (human ovarian granulosa cell line) was used as PCOS cell model and was transfected with siSIRT1 in the presence of CAT. The viability, proliferation and apoptosis of cells and the levels of SIRT1 and NF-κB pathway-related proteins were measured. CAT lessened the anthropometric indices and improved ovarian damage in PCOS model rats, and reduced the levels of testosterone, estradiol, progesterone and MDA, increased GSH content, and elevated the activities of catalase, GSH-Px and SOD in ovarian tissues of PCOS model rats. CAT up-regulated SIRT1 level and inhibited the activation of NF-κB signaling pathway in PCOS rat model and KGN cells. Silencing SIRT1 increased the viability and proliferation, whilst decreased the apoptosis of CAT-treated KGN cells. Silencing SIRT1 counteracted the effect of CAT on the level of oxidative stress-related factors and NF-κB signaling pathway in KGN cells. CAT attenuated PCOS by regulating SIRT1 mediated NF-κB signaling pathway.


Assuntos
Síndrome do Ovário Policístico , Animais , Estradiol , Feminino , Células da Granulosa , Humanos , Glucosídeos Iridoides , NF-kappa B , Progesterona , Ratos , Transdução de Sinais , Sirtuína 1 , Testosterona
7.
Front Neurol ; 13: 893401, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35812109

RESUMO

Background: Abdominal obesity and adipocytokines are closely related to atherosclerosis, and adiponectin level is considered one of the important clinical indicators. This study aimed to analyze the associations of abdominal visceral fat content and adiponectin level with intracranial atherosclerotic stenosis (ICAS). Methods: A total of 186 patients were enrolled in this study. Patients were distributed into ICAS and non-ICAS by the degree of artery stenosis. Plasma adiponectin levels and the ratio of visceral adipose tissue (VAT) to subcutaneous adipose tissue (SAT) were measured. The related factors of intracranial atherosclerotic stenosis were determined using multivariable logistic regression analysis. Results: The VAT/SAT ratio (OR, 26.08; 95% CI, 5.92-114.83; p < 0.001) and adiponectin (OR, 0.61; 95% CI, 0.44-0.84; p = 0.002) were found to be the independent predictors of ICAS in a multivariable logistic regression analysis. The prevalence of ICAS increased (T1: 27.4%; T2: 50.0%; T3: 75.8%) as the VAT/SAT ratio tertile increased (p < 0.001). The prevalence of ICAS decreased (T1: 72.6%; T2: 54.8%; T3: 25.8%) as the adiponectin tertile increased (p < 0.001). In ROC curves analysis, VAT/SAT ratio had a sensible accuracy for the prediction of ICAS. The optimal cut-off value of VAT/SAT ratio to predict ICAS in this study was 1.04 (AUC: 0.747; p < 0.001; sensitivity: 67.4%; specificity: 74.7%). The optimal adiponectin cutoff was 3.03 ug/ml (AUC: 0.716; p < 0.001; sensitivity:75.8%; specificity: 61.5%). Conclusion: Higher VAT/SAT ratio and lower plasma adiponectin levels were closely related to the increased risk of intracranial atherosclerotic stenosis.

8.
Adv Sci (Weinh) ; 9(15): e2106029, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35338594

RESUMO

Developing an economical, durable, and efficient electrode that performs well at high current densities and is capable of satisfying large-scale electrochemical hydrogen production is highly demanded. A self-supported electrocatalytic "Pt-like" WC porous electrode with open finger-like holes is produced through industrial processes, and a tightly bonded nitrogen-doped WC/W (WC-N/W) heterostructure is formed in situ on the WC grains. The obtained WC-N/W electrode manifests excellent durability and stability under multi-step current density in the range of 30-1000 mA cm-2 for more than 220 h in both acidic and alkaline media. Although WC is three orders of magnitude cheaper than Pt, the produced electrode demonstrates comparable hydrogen evolution reaction performance to the Pt electrode at high current density. Density functional theory calculations attribute its superior performance to the electrode structure and the modulated electronic structure at the WC-N/W interface.

9.
Environ Sci Technol ; 55(8): 5324-5334, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33728905

RESUMO

Modulation of the polyamide structure is critically important for the reverse-osmosis performance of thin-film composite (TFC) membranes in the field of water reuse and desalination. Herein, zwitterionic nanoparticles of zeolitic imidazolate framework-8 (PZ@ZIF-8) were fabricated and incorporated into the polyamide active layer through the interfacial polymerization method. A hydrophilic, zwitterionic coffee-ring structure was formed on the surface of polyamide thin-film nanocomposite (TFN) membranes due to the adjusted diffusion rate of m-phenylenediamine (MPD) from the aqueous phase into the organic phase during the interfacial polymerization process. Surface characterization demonstrated that the coffee-ring structure increased the amounts of water transport channels on the membrane surface and the intrinsic pores of PZ@ZIF-8 maintained the salt rejection. Antifouling and bactericidal activities of TFN membranes were enhanced remarkably owing to the bacterial-"defending" and bacterial-"attacking" behaviors of hydrophilic and zwitterionic groups from PZ@ZIF-8 nanoparticles. This work would provide a promising method for the application of MOFs to enhance the bio-/organic-fouling resistance of TFN membranes with high water permeation and salt rejection.


Assuntos
Estruturas Metalorgânicas , Nylons , Café , Permeabilidade , Água
10.
Neural Plast ; 2020: 8855822, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33299399

RESUMO

Microglia activation contributes to Alzheimer's disease (AD) etiology, and microglia migration is a fundamental function during microglia activation. The repressor element-1 silencing transcription factor (REST), a powerful transcriptional factor, was found to play a neuroprotective role in AD. Despite its possible role in disease progression, little is known about whether REST participates in microglia migration. In this study, we aimed to explore the function of REST and its molecular basis during microglia migration under Aß 1-42-treated pathological conditions. When treated by Aß 1-42 REST was upregulated through JAK2/STAT3 signal pathway in BV2 cells. And transwell coculture system was used to evaluate cell migration function of microglia-like BV2. Small interfering RNA (siRNA) targeting progranulin (PGRN) were delivered into BV2 cells, and results showed that PGRN functions to promote BV2 migration. REST expression was inhibited by sh-RNA, which induced BV2 cell migration obviously. On the contrary, REST was overexpressed by REST recombinant plasmid transfection, which repressed BV2 cell migration, indicating that REST may act as a repressor of cell migration. To more comprehensively examine the molecular basis, we analyzed the promoter sequence of PGRN and found that it has the potential binding site of REST. Moreover, knocking-down of REST can increase the expression of PGRN, which confirms the inhibiting effect of REST on PGRN expression. Further detection of double luciferase reporter gene also confirmed the inhibition of REST on the activity of PGRN promoter, indicating that REST may be an inhibitory transcription factor of PGRN which governs microglia-like BV2 cell migration. In conclusion, the present study demonstrates that transcription factor REST may act as a repressor of microglia migration through PGRN.


Assuntos
Doença de Alzheimer/metabolismo , Movimento Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Microglia/metabolismo , Progranulinas/metabolismo , Humanos , Transdução de Sinais/fisiologia , Fatores de Transcrição/metabolismo
11.
Neural Plast ; 2020: 8888871, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33029126

RESUMO

Compelling evidence from basic molecular biology has demonstrated the crucial role of microglia in the pathogenesis of Alzheimer's disease (AD). Microglia were believed to play a dual role in both promoting and inhibiting Alzheimer's disease progression. It is of great significance to regulate the function of microglia and make them develop in a favorable way. In the present study, we investigated the function of repressor element 1-silencing transcription factor (REST) in Aß 1-42-induced BV-2 cell dysfunction. We concluded that Aß 1-42 could promote type I activation of BV-2 cells and induce cell proliferation, migration, and proinflammation cytokine TNF-α, IL-1ß, and IL-6 expression. Meanwhile, REST was upregulated, and nuclear translocalization took place due to Aß 1-42 stimulation. When REST was knocked down by a specific short hairpin RNA (sh-RNA), BV-2 cell proliferation, migration, and proinflammation cytokine expression and secretion induced by Aß 1-42 were increased, demonstrating that REST may act as a repressor of microglia-like BV-2 cell activation.


Assuntos
Peptídeos beta-Amiloides/administração & dosagem , Peptídeos beta-Amiloides/metabolismo , Microglia/metabolismo , Fragmentos de Peptídeos/administração & dosagem , Fragmentos de Peptídeos/metabolismo , Proteínas Repressoras/metabolismo , Animais , Linhagem Celular , Proliferação de Células , Técnicas de Transferência de Genes , Camundongos , Proteínas Repressoras/genética
12.
Water Res ; 182: 116030, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679388

RESUMO

Low cost, green, regenerable catalyst for persulfate activation is the popularly concerned topic for the degradation of persistent organic micropollutants in drinking water. In this work, natural montmorillonite (MMT) saturated with Fe(III) ions was used to activate peroxymonosulfate (PMS) for the degradation of atrazine in raw drinking water. Results showed that the adsorption of atrazine was quickly completed within 1 min and the percentage degradation was finally increased up to 94.1% in 60 min. The d001-spacing of MMT was enlarged to 2.91 nm at the most by Fe(III) saturation. Atrazine was adsorbed into the nanoscale interlayer of Fe(III)-saturated montmorillonite (Fe-MMT), where the Fe(III)/Fe(II) cycle was sustainably realized through the accelerated transformation of electrons between Fe(III) and PMS. Meanwhile, the in-situ generated Fe(II) accelerated the decomposition of PMS to further proceed the degradation of atrazine through the oxidation of HO• and SO4•- radicals. This nanoconfined effect of PMS activation by Fe(III) was further confirmed through the degradation of various micropollutants in the backgrounds of river water. The selective catalytic oxidation of micropollutants through PMS activation was attributed to the 2D mesoporous structure of Fe-MMT, inhibiting the interlayer adsorption of larger molecular backgrounds (humic acids etc.). Fe(III)-saturated montmorillonite (Fe-MMT) provided a feasible and scalable method of PMS activation by Fe(III) for the degradation of micropollutants in drinking water.


Assuntos
Bentonita , Poluentes Químicos da Água/análise , Compostos Férricos , Compostos Ferrosos , Peróxidos
13.
Water Res ; 175: 115649, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32200335

RESUMO

Increasing attention has been focused on the removal of micropollutants from contaminated drinking source water. However, low rejection efficiency and membrane fouling still inhibit further application of nanofiltration membrane in this field. Interesting results were found that the residual hydrolyzed-aluminum nanoparticles from supernatant after coagulation and sedimentation strongly improved the nanofiltration performance for micropollutant removal. A simulated raw water containing humic acids, micropollutants and kaolinite clay was employed to investigate the factors of water matrix affecting the nanoparticle-enhanced nanofiltration for micropollutant removal. Results of experiments showed that these hydrolyzed-aluminum nanoparticles easily induced the aggregation of bisphenol-A (BPA) and humic acids in the supernatant. The enhancement of BPA removal was mainly attributed to the repelling interaction between the Al-BPA-DOC complexity and in situ-modified membrane surface during nanofiltration. 'This in situ surface modification by the hydrolyzed-aluminum nanoparticles improved membrane hydrophilicity, roughness and positively-charging capacity. For the treatment of River Songhua water spiked with micropollutant, the percentage removal of BPA was improved to be 88.5%, much more than the case of single nanofiltration without coagulation (60.7%). Meanwhile, the membrane fouling was reduced by 2.13 times than the case of single nanofiltration without the dynamically deposited-layer of nanoparticles. This in situ modification of nanofiltration membrane by hydrolyzed-aluminum nanoparticles achieved excellent removal efficiency for micropollutants from River Songhua water background.


Assuntos
Nanopartículas , Purificação da Água , Alumínio , Substâncias Húmicas , Membranas Artificiais
14.
Chemistry ; 26(9): 2034-2040, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31696569

RESUMO

A new hatted 1T/2H-phase MoS2 on Ni3 S2 nanorods, as a bifunctional electrocatalyst for overall water splitting in alkaline media, is prepared through a simple one-pot hydrothermal synthesis. The hat-rod structure is composed mainly of Ni3 S2 , with 1T/2H-MoS2 adhered to the top of the growth. Aqueous ammonia plays an important role in forming the 1T-phase MoS2 by twisting the 2H-phase transition and expanding the interlayer spacing through the intercalation of NH3 /NH4 + . Owing to the special "hat-like" structure, the electrons conduct easily from Ni foam along Ni3 S2 to MoS2 , and the catalyst particles maintain sufficient contact with the electrolyte, with gaseous molecules produced by water splitting easily removed from the surface of the catalyst. Thus, the electrocatalytic performance is enhanced, with an overpotential of 73 mV, a Tafel slope of 79 mV dec-1 , and excellent stability, and the OER demonstrates an overpotential of 190 mV and Tafel slope of 166 mV dec-1 .

15.
ACS Appl Mater Interfaces ; 11(45): 42801-42807, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31657542

RESUMO

Self-cleaning materials have attracted immense commercial and academic interests in recent years. A major challenge is the scalable and cost-effective fabrication of three-dimensional bulk materials with remarkable self-cleaning and a desirable combination of tailored porosity, robust superhydrophobicity, excellent mechanical strength, heat insulation, and sound absorption ability. Here, self-cleaning concrete was achieved in one step through the combination of the liquid template pore formation and in situ bulk hydrophobic modification. The concrete exhibited superhydrophobicity with a high water contact angle of 166° both on the surface and inside of the sample, which qualified the sample with remarkable stain repellency and long-term stability. The water contact angle remained unchanged under continuous mechanical grinding and harsh environments, such as high temperature (450 °C in air and 650 °C in Ar) and chemical erosion. The concrete with a controllable porosity from 56.3 to 77.4% and homogeneous small pore size (∼15 µm) exhibited high compressive strength and low thermal conductivity. Furthermore, high sound absorption capacity (97%, 500 Hz) at a vibration frequency from 400 to 600 Hz was realized. With these excellent performances and characteristics and easy scalable fabrication, the concrete prepared in this work possessed a wide application prospect.

16.
ACS Appl Mater Interfaces ; 11(36): 33033-33042, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31436947

RESUMO

Reverse osmosis (RO) is an emerging membrane technology for disinfection byproducts (DBPs) removal. However, the chlorine-resistance and DBPs removal performance of thin film composite (TFC) polyamide membranes should be simultaneously improved when used in chlorinated drinking water. This study was dedicated to synthesize a novel nanoparticle of ZIF-8 with carbon dots (CDs@ZIF-8) and then modify thin film nanocomposite (TFN) membranes to enhance their performance in removing four trihalomethanes (THMs), four haloacetonitriles (HANs), and two haloketones (HKs) in chlorinated drinking water. The fabricated CDs@ZIF-8 nanoparticles and TFN membranes were characterized by FESEM, AFM, XPS, water contact angle, membrane surface potential, and a three-dimensional excitation-emission matrix (EEM) to investigate the influences of CDs@ZIF-8 on TFN membranes. After chlorination, percentage reduction in salt rejection of the CDs@ZIF-8 TFN membranes was lower than that of the TFC membranes due to hydrogen bonding between CDs and polyamide, replacing amidic hydrogen with chlorine, rendering the membrane less susceptible to chlorine attack and enhancing chlorine-resistance. Results also showed that the rejection of DBPs in chlorinated drinking water by CDs@ZIF-8 TFN membranes was more than 95%. The large surface area and abundant oxygen-containing groups of CDs@ZIF-8 made the nanoparticle act as a nanocarbon filler with high adsorption capacity of DBPs. The enhanced performances of chlorine-resistance and DBPs removal by CDs@ZIF-8 TFN membranes determined in this study provided valuable insights on the DBPs control in chlorinated drinking water by RO membranes.


Assuntos
Cloro/análise , Desinfecção , Água Potável/química , Membranas Artificiais , Nanocompostos/química , Nylons/química , Pontos Quânticos/química , Compostos de Zinco/química , Carbono/química , Espectroscopia Fotoeletrônica , Pontos Quânticos/ultraestrutura , Espectrofotometria Ultravioleta , Poluentes Químicos da Água/isolamento & purificação
17.
Chemosphere ; 233: 524-531, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31185336

RESUMO

Metal-organic frameworks (MOFs) addition into membranes is able to improve water flux without jeopardizing selectivity, which enhance the performance of reverse osmosis (RO) processes owing to its intrinsic physical and chemical properties, such as porosity structure and high compatibility with the polymer matrix. However, there were few studies about influences of nanoparticle size on MOFs-incorporated thin film nanocomposite (TFN) membranes. Here ZIF-8 particles with different average sizes (50, 150 and 400 nm) were synthesized and incorporated into organic monomer solution to fabricate TFN membranes for water desalination to investigate the membrane performance changed by nanomaterial size. Dispersion of ZIF-8 in selective layer during interfacial polymerization process was affected by particle size. The apparent morphology, roughness, and hydrophilicity of ZIF-8 modified TFN membranes were changed subsequently, which affected the water permeability, salt rejection and fouling resistance performance of the TFN membranes correspondingly. Our results showed that the TFN membrane comprising ZIF-8 with particle size of 50 nm had the best performance due to the highest dispersion in polyamide layer, revealing the importance of MOFs particle size in further investigation of MOFs-incorporated TFN membranes.


Assuntos
Filtração/métodos , Membranas Artificiais , Estruturas Metalorgânicas/química , Nanopartículas/química , Nylons/química , Purificação da Água/métodos , Zinco/química , Interações Hidrofóbicas e Hidrofílicas , Nanocompostos/química , Osmose , Tamanho da Partícula , Permeabilidade , Porosidade , Propriedades de Superfície
18.
Aging (Albany NY) ; 11(10): 3094-3116, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31097679

RESUMO

Many infertile women suffered from poor ovarian response, and increased reactive oxygen species with age might mediate the poor ovarian response to FSH. In this study, we collected follicular fluids and isolated granulosa cells from female patients. Increased levels of peroxynitrite, tyrosine nitrations of FSH receptor (FSHR) and apoptosis were obviously detectable with decreased FSHR protein expressions in granulosa cells of the poor ovarian responders. In KGN (a human ovarian granulosa cell line) cells, exogenous peroxynitrite could sequester FSHR in the cytoplasm, and these dislocated FSHR might suffer from proteasome-mediated degradations. Here, we identified four peroxynitrite-mediated nitrated tyrosine residues of FSHR. Site-directed mutagenesis of FSHR revealed that Y626 was pivotal for intracellular trafficking of FSHR to the cell surface. Akt-induced inactivation of FoxO3a was required for the repression of FSH on granulosa cell apoptosis. However, peroxynitrite impaired FSH-induced Akt-FoxO3a signaling, while FSHR-Y626A mutant took similar effects. In addition, FoxO3a knockdown indeed impaired FSH-mediated cell survival, while FoxO3a-S253A mutant reversed that significantly.


Assuntos
Células da Granulosa/metabolismo , Estresse Oxidativo , Receptores do FSH/metabolismo , Adulto , Linhagem Celular , Feminino , Hormônio Foliculoestimulante , Proteína Forkhead Box O3/metabolismo , Humanos , Mutagênese Sítio-Dirigida , Ácido Peroxinitroso , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores do FSH/genética , Tirosina/metabolismo
19.
Attach Hum Dev ; 18(6): 534-553, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27734761

RESUMO

This research examined the child, parent, and family conditions under which attachment disorganization was related to both level and change in externalizing behavior during preschool among a community sample. Using the ordinary least squares regression, we found that attachment disorganization at 12 months significantly predicted children's externalizing behavior at 36 months and this prediction was not contingent on any other factors tested. For predicting changes in externalizing behavior from 36 to 60 months, we found a significant main effect of family cumulative risk and an interaction effect between attachment disorganization at 12 months and maternal sensitivity at 24 months. Specifically, high disorganization was related to a significant decrease in externalizing behavior from 36 to 60 months when maternal sensitivity at 24 months was high. Our main-effect findings replicated the significant effect of attachment disorganization and cumulative risk on externalizing behavior with preschool-aged children. Our interaction finding provided support for understanding the parenting conditions under which infant attachment disorganization may be related to change in externalizing behavior during preschool ages. Implications of the findings were discussed.


Assuntos
Transtornos do Comportamento Infantil/psicologia , Comportamento Infantil/psicologia , Comportamento Materno/psicologia , Relações Mãe-Filho/psicologia , Apego ao Objeto , Adulto , Fatores Etários , Transtornos do Comportamento Infantil/epidemiologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos
20.
Immunol Lett ; 179: 114-121, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27717876

RESUMO

Neuroinflammation plays an important role in the recovery of brain injury in ICH. Macrophage is the major executor in the neuroinflammation and initiates neurological defects. Programmed death 1 (PD-1) delivers inhibitory signals that regulate the balance between T cell activation, tolerance, and immunopathology. PD-1 expression by macrophages plays a pathologic role in the innate inflammatory response. However, the exact role of PD-1 on inflammatory responses following ICH has not been well identified. In this experiment, PD-1 KO (PD-1 -/-) ICH mice and Wild-type (WT) ICH mice were caused by intracranial injection of type IV collagenase. The level of macrophage activation, inflammatory cytokines and fibrinogen-like protein 2 (Fgl-2) were detected using immunofluorescence staining and ELISA assays. In addition, brain edema and neurological scores of ICH mice were also measured. Our data demonstrated that ICH promoted PD-1 expression of macrophage and enhanced inflammatory cytokines and Fgl-2 concentrations. PD-1 -/- mice exhibited significantly higher expression of the inflammatory cytokines which initiate Fgl-2, than did their wild-type (WT) littermates. As a result, macrophage activation, cerebral edema and neurological deficit scores of PD-1 -/- mice were higher. In conclusion, our data demonstrate that PD-1 plays a vital role in brain inflammation via regulation of Fgl-2 after ICH, and that manipulation of PD-1 might be a promising therapeutical target in ICH.


Assuntos
Hemorragia Cerebral/complicações , Encefalite/etiologia , Encefalite/metabolismo , Fibrinogênio/metabolismo , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Macrófagos/metabolismo , Receptor de Morte Celular Programada 1/metabolismo , Animais , Hemorragia Cerebral/etiologia , Citocinas/metabolismo , Modelos Animais de Doenças , Encefalite/patologia , Fibrinogênio/genética , Expressão Gênica , Imuno-Histoquímica , Mediadores da Inflamação/metabolismo , Camundongos , Camundongos Knockout , Receptor de Morte Celular Programada 1/genética
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