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1.
Environ Res ; 216(Pt 4): 114808, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36379237

RESUMO

Crystal plane regulation, defect engineering, and element doping can effectively solve the problems of large band gaps, poor light absorption, and fast recombination of BiOCl. In this work, iodine-doped BiOCl (I/BiOCl) nanowafers with abundant (110) crystal planes and oxygen vacancies (OV) were prepared by a simple hydrothermal method and assessed for pollutant photodegradation. I/BiOCl with a molar ratio of I to Cl of 0.6 (I0.6/BiOCl) degraded under visible light 95.8% of the toxic dye rhodamine B and 85.1% of the persistent antibiotic tetracycline in 5 and 10 min, respectively. In comparison, unmodified BiOCl photodegraded only between 42.0% and 48.2% of these critical water pollutants. Furthermore, I0.6/BiOCl was highly stable with most of its photocatalytic activity remaining after 4 cycles. Three reasons explain the excellent photodegradation properties of I0.6/BiOCl. First, the doped photocatalyst grew abundant (110) crystal planes, which inhibits the recombination of photogenerated electron-hole pairs. Second, the large quantity of OV present in I0.6/BiOCl increased active sites for reactive oxygen species generation, improved photogenerated charge separation, and pollutants adsorption. Lastly, I0.6/BiOCl had a modified electronic band structure enhancing light absorption. Overall, these results describe a promising photocatalyst capable of degrading efficiently major pollutants with different structures.


Assuntos
Poluentes Ambientais , Iodo , Fotólise , Oxigênio , Tetraciclina , Antibacterianos
2.
Chemosphere ; 312(Pt 1): 137249, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36400196

RESUMO

Effective strategies to improve charge separation in semiconductor particles are critical for improving the photodegradation of organic pollutants at levels sufficient for environmental applications. Herein, Bi2MoO6 (BMOMOF), comprising both nanoparticles (NPs) and quantum dots (QDs), was synthesized from a bismuth-based metal-organic framework (Bi-MOF) precursor. Surface defects on BMOMOF, the combination of NPs and QDs, and modified energy band edges improved photogenerated charge separation and facilitated redox reactions. When compared to BMO derived from uncoordinated Bi, the BMOMOF photocatalyst (PC) was more efficient at photodegrading tetracycline hydrochloride (TCH) and ciprofloxacin (CIP), two widely-used antibiotics ubiquitous in wastewater, as well as the carcinogenic pollutant rhodamine B (RhB). BMOMOF was then loaded on the biopolymer bacterial cellulose (BC) to further enhance photocatalytic performance and facilitate the recovery of the PC after water treatment processes. The novel BMOMOF/BC photocatalytic flakes were significantly larger than pure BMOMOF, and thus easier to recuperate. Furthermore, anchoring BMOMOF on BC flakes augmented significantly the photodegradation of TCH, CIP, and RhB, mainly because hydroxyl groups in BC act as hole traps facilitating photogenerated electron-hole separation. Results obtained with BMOMOF/BC highlight promising approaches to develop optimal PCs for aqueous pollutants degradation.


Assuntos
Poluentes Ambientais , Nanopartículas , Pontos Quânticos , Celulose , Fotólise , Antibacterianos , Ciprofloxacina , Tetraciclina , Catálise
3.
Cell Signal ; 108: 110696, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37409402

RESUMO

Apolipoprotein E (APOE) was recognized as a key regulator of lipid metabolism, which prompted the Apoe-knockout (Apoe-/-) mouse to be the most widely used atherosclerotic model. However, with more and more important physiological roles of APOE being revealed, it is necessary to reacquaint its comprehensive function in the aorta. In this study, we aimed to reveal how Apoe-knockout impacts the gene pathways and phenotypes in the aorta of mice. We performed transcriptome sequencing to acquire the gene expression profile (GEP) for C57BL/6J and Apoe-/- mouse aorta, and used enrichment analysis to reveal the signal pathways enriched for differentially expressed genes (DEGs). In addition, we used immunofluorescence and ELISA to detect the phenotypic differences of vascular tissues and plasma in the two-group mice. Apoe-knockout resulted in significant changes in the expression of 538 genes, among which about 75% were up-regulated and 134 genes were altered more than twice. In addition to the lipid metabolism pathways, DEGs were also mainly enriched in the pathways implicated in endothelial cell proliferation, migration of epithelial cells, immune regulatory, and redox. GSEA shows that the up-regulated genes are mainly enriched in 'immune regulation pathways' and 'signal regulation' pathways, while the down-regulated genes are enriched in lipid metabolism pathways, 'regulation_of_nitric_oxide_synthase_activity' and the pathways involved in redox homeostasis, including 'monooxygenase regulation', 'peroxisomes' and 'oxygen binding'. A significant increase of reactive oxygen species and a remarkable reduction of GSH/GSSG ratio were respectively observed in the vascular tissues and plasma of Apoe-/- mice. In addition, endothelin-1 significantly increased in the vascular tissue and the plasma of Apoe-/- mice. Taken together, our results suggest that besides functioning in lipid metabolism, APOE may be an important signal regulator that mediates the expression of the genes related to the pathways involved in redox, inflammation, and endothelial function. Apoe-knockout-induced strong vascular oxidative stress is also the key factor contributing to atherosclerosis.


Assuntos
Aterosclerose , Transcriptoma , Camundongos , Animais , Transcriptoma/genética , Camundongos Knockout , Camundongos Endogâmicos C57BL , Estresse Oxidativo , Inflamação/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo , Oxirredução , Apolipoproteínas E/genética , Apolipoproteínas E/metabolismo
4.
Sheng Wu Gong Cheng Xue Bao ; 37(8): 2779-2785, 2021 Aug 25.
Artigo em Zh | MEDLINE | ID: mdl-34472295

RESUMO

To investigate whether the engineered Lactobacillus plantarum expressing the porcine epidemic diarrhea virus (PEDV) S1 gene can protect animals against PEDV, guinea pigs were fed with recombinant L. plantarum containing plasmid PVE5523-S1, with a dose of 2×108 CFU/piece, three times a day, at 14 days intervals. Guinea pigs fed with wild type L. plantarum and the engineered L. plantarum containing empty plasmid pVE5523 were used as negative controls. For positive control, another group of guinea pigs were injected with live vaccine for porcine epidemic diarrhea and porcine infectious gastroenteritis (HB08+ZJ08) by intramuscular injection, with a dose of 0.2 mL/piece, three times a day, at 14 days intervals. Blood samples were collected from the hearts of the four groups of guinea pigs at 0 d, 7 d, 14 d, 24 d, 31 d, 41 d and 48 d, respectively, and serum samples were isolated for antibody detection and neutralization test analysis by enzyme-linked immunosorbent assay (ELISA). The spleens of guinea pigs were also aseptically collected to perform spleen cells proliferation assay. The results showed that the engineered bacteria could stimulate the production of secretory antibody sIgA and specific neutralizing antibody, and stimulate the increase of IL-4 and IFN-γ, as well as the proliferation of spleen cells. These results indicated that the engineered L. plantarum containing PEDV S1 induced specific immunity toward PEDV in guinea pigs, which laid a foundation for subsequent oral vaccine development.


Assuntos
Infecções por Coronavirus , Lactobacillus plantarum , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Vacinas Virais , Animais , Anticorpos Antivirais , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Cobaias , Lactobacillus plantarum/genética , Vírus da Diarreia Epidêmica Suína/genética , Suínos , Vacinas Virais/genética
5.
Neurosci Bull ; 29(1): 16-27, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23361519

RESUMO

Methylphenidate (MPH) is one of the most commonly used stimulants for the treatment of attention deficit hyperactivity disorder (ADHD). Although several studies have evaluated the effects of MPH on human brain activation during specific cognitive tasks using functional magnetic resonance imaging (fMRI), few studies have focused on spontaneous brain activity. In the current study, we investigated the effect of MPH on the intra-regional synchronization of spontaneous brain activity during the resting state in 18 normal adult males. A handedness questionnaire and the Wechsler Adult Intelligence Scale were applied before medication, and a resting-state fMRI scan was obtained 1 h after medication (20 mg MPH or placebo, order counterbalanced between participants). We demonstrated that: (1) there were no significant differences in the performance of behavioral tasks between the MPH and placebo groups; (2) the left middle and superior temporal gyri had stronger MPHrelated regional homogeneity (ReHo); and (3) the left lingual gyrus had weaker MPH-related ReHo. Our findings showed that the ReHo in some brain areas changes with MPH compared to placebo in normal adults, even though there are no behavioral differences. This method can be applied to patients with mental illness who may be treated with MPH, and be used to compare the difference between patients taking MPH and normal participants, to help reveal the mechanism of how MPH works.


Assuntos
Encéfalo/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/farmacologia , Metilfenidato/farmacologia , Vias Neurais/efeitos dos fármacos , Encéfalo/fisiologia , Cerebelo/efeitos dos fármacos , Cerebelo/fisiologia , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiologia , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Potenciais da Membrana/efeitos dos fármacos , Neostriado/efeitos dos fármacos , Neostriado/fisiologia , Vias Neurais/fisiologia , Projetos Piloto , Valores de Referência , Adulto Jovem
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