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1.
Dalton Trans ; 53(18): 8011-8019, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38651951

RESUMO

Designing efficient, inexpensive, and stable photocatalysts to degrade organic pollutants and antibiotics has become an effective way for environmental remediation. In this work, we successfully performed in situ growth of CdS QDs on the surface of elliptical BiVO4 to try to show the advantage of the binary heterojuncted photocatalyst (BVO@CdS) for the photocatalytic degradation of tetracycline (TC). The In situ growth of CdS QDs can provide a large number of reactive sites and also generate a larger contact area with BiVO4. In addition, compared with mechanical composite materials, in situ growth can significantly reduce the energy barrier at the interface between BiVO4 and CdS, providing more channels for the separation and migration of photogenerated charge carriers, and further improving reaction activity. As a result, BVO@CdS-0.05 shows the best degradation efficiency, with a degradation rate of 88% after 30 min under visible light. The TC photodegradation follows a pseudo-second-order reaction with a dynamic constant of 0.472 min-1, which is 6.47 times that of pure BiVO4, 7.24 times that of pure CdS QDs and 2 times that of the mechanical composite. The degradation rate of BVO@CdS-0.05 decreases to 77.8% with a retention rate of 88.5% after four cycles, demonstrating excellent stability. Through liquid chromatography-mass spectrometry (LC-MS) analysis, two possible pathways for TC degradation are proposed. Through free radical capture experiments, electron spin resonance measurements, and photoelectrochemical comprehensive analysis, it is confirmed that BVO@CdS composites have constructed an efficient Z-scheme heterojunction via in situ growth, thereby highly enhancing the separation and transport efficiency of charge carriers.

2.
RNA Biol ; 16(6): 809-820, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30836863

RESUMO

Doublesex is highly conserved and sex-specifically spliced in insect sex-determination pathways, and its alternative splicing (AS) is regulated by Transformer, an exonic splicing activator, in the model system of Drosophila melanogaster. However, due to the lack of a transformer gene, AS regulation of doublesex remains unclear in Lepidoptera, which contain the economically important silkworm Bombyx mori and thousands of agricultural pests. Here, we use yeast three-hybrid system to screen for RNA-binding proteins that recognize sex-specific exons 3 and 4 of silkworm doublesex (Bm-dsx); this approach identified BxRBP1/Lark binding to the exon 3, and BxRBP2/TBPH and BxRBP3/Aret binding to the exon 4. Investigation of tissues shows that BxRBP1 and BxRBP2 have no sex specificity, but BxRBP3 has - three of its four isoforms are expressed with a sex-bias. Using novel sex-specific silkworm cell lines, we find that BxRBP1 and BxRBP3 directly interact with each other, and cooperatively function as splicing repressors. Over-expression of BxRBP1 and BxRBP3 isoforms efficiently inhibits splicing of the exons 3 and 4 in the female-specific cells and generates the male-specific isoform of Bm-dsx. We also demonstrate that the sex-determination upstream gene Masc regulates alternatively transcribed BxRBP3 isoforms. Thus, we identify a new regulatory mechanism of doublesex AS in the silkworm, revealing an evolutionary divergence in insect sex-determination.


Assuntos
Processamento Alternativo , Bombyx/genética , Proteínas de Ligação a DNA/genética , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Bombyx/metabolismo , Proteínas de Ligação a DNA/metabolismo , Éxons , Feminino , Genes de Insetos , Proteínas de Insetos/química , Masculino , Sinais de Localização Nuclear , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Caracteres Sexuais , Transcrição Gênica
4.
Angew Chem Int Ed Engl ; 56(17): 4767-4771, 2017 04 18.
Artigo em Inglês | MEDLINE | ID: mdl-28345204

RESUMO

A crack-free sub-nanometer composite structure for the study of ion transfer was constructed by in situ growth of ZIF-90 [Zn(ICA)2 , ICA=Imidazole-2-carboxaldehyde] on the tip of a glass nanopipette. The potential-driven ion transfer through the sub-nanometer channels in ZIF-90 is strongly influenced by the pH of the solution. A rectification ratio over 500 is observed in 1 m KCl solution under alkaline conditions (pH 11.58), which is the highest value reported under such a high salt concentration. Fluorescence experiments show the super-high rectification ratio under alkaline conditions results from the strong electrostatic interaction between ions and the sub-nanometer channels of ZIF-90. In addition to providing a general pathway for further study of mass-transfer process through sub-nanometer channels, the approach enable all kinds of metal-organic frameworks (MOFs) to be used as ionic permselectivity materials in nanopore-based analysis.

5.
Psychiatry Clin Neurosci ; 70(8): 351-61, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27177717

RESUMO

AIM: The aim of this updated meta-analysis was to further assess the effectiveness of cognitive behavioral therapy (CBT) in treating bipolar disorder (BD). METHODS: We carried out a literature search on PubMed, Embase, and the Cochrane Library up to October 2015. We calculated the pooled relative risk of relapse rate and standard mean difference (SMD) of mean change (data at a follow-up time-point - baseline) of the Beck Depression Inventory, Beck Hopelessness Scale, Hamilton Rating Scale for Depression, Young Mania Rating Scale (YMRS) and Mania Rating Scale scores with their 95% confidence interval (95%CI). Subgroup analyses based on follow-up time were performed. RESULTS: Nine randomized controlled trials with 520 bipolar I or II disorder patients were reanalyzed. Overall analysis showed that CBT did not significantly reduce the relapse rate of BD or improve the level of depression. However, significant efficacy of CBT in improving severity of mania was proved based on the YMRS (SMD = -0.54, 95%CI, -1.03 to -0.06, P = 0.03) but not based on MRS. Subgroup analyses showed that CBT had short-term efficacy in reducing relapse rate of BD (at 6 months' follow-up: relative risk = 0.49, 95%CI: 0.29-0.81, P = 0.006) and improving severity of mania based on YMRS score (post-treatment: SMD = -0.30, 95%CI, -0.59 to -0.01, P = 0.04). CONCLUSION: Short-term efficacy of CBT in reducing relapse rate of BD and improving the severity of mania was proved. But these effects could be weakened by time. In addition, there was no effect of CBT on level of depression in BD.


Assuntos
Transtorno Bipolar/terapia , Terapia Cognitivo-Comportamental/métodos , Avaliação de Resultados em Cuidados de Saúde/estatística & dados numéricos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Humanos
6.
Inflammation ; 39(1): 148-157, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26272311

RESUMO

Acute lung injury (ALI), a common component of systemic inflammatory disease, is a life-threatening condition without many effective treatments. Fisetin, a natural flavonoid from fruits and vegetables, was reported to have wide pharmacological properties such as anti-inflammatory, antioxidant, and anticancer activities. The aim of this study was to detect the effects of fisetin on lipopolysaccharide (LPS)-induced acute lung injury and investigate the potential mechanism. Fisetin was injected (1, 2, and 4 mg/kg, i.v.) 30 min before LPS administration (5 mg/kg, i.v.). Our results showed that fisetin effectively reduced the inflammatory cytokine release and total protein in bronchoalveolar lavage fluids (BALF), decreased the lung wet/dry ratios, and obviously improved the pulmonary histology in LPS-induced ALI. Furthermore, fisetin inhibited LPS-induced increases of neutrophils and macrophage infiltration and attenuated MPO activity in lung tissues. Additionally, fisetin could significantly inhibit the Toll-like receptor 4 (TLR4) expression and the activation of NF-κB in lung tissues. Our data indicates that fisetin has a protective effect against LPS-induced ALI via suppression of TLR4-mediated NF-κB signaling pathways, and fisetin may be a promising candidate for LPS-induced ALI treatment.


Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Flavonoides/farmacologia , Lipopolissacarídeos/farmacologia , NF-kappa B/metabolismo , Receptor 4 Toll-Like/biossíntese , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar/química , Ativação Enzimática/efeitos dos fármacos , Flavonóis , Interleucina-6/metabolismo , Pulmão/patologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Masculino , Infiltração de Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/metabolismo
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