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1.
J Colloid Interface Sci ; 673: 1-8, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38870663

RESUMEN

Heterojunctions photocatalysts play a crucial role in achieving high solar-hydrogen conversion efficiency. In this work, we mainly focus on the charge transfer dynamics and pathways for sulfides-based Schottky junctions in the photocatalytic water splitting process to clarify the mechanism of heterostructures photocatalysis. Sulfides-based Schottky junctions (CdS/CoP and CdS/1T-MoS2) were successfully constructed for photocatalytic water splitting. Because of the higher work function of CdS than that of CoP and 1T-MoS2, the direction of the built-in electric field is from CoP or 1T-MoS2 to semiconductor. Therefore, CoP and 1T-MoS2 can act as electrons acceptors to accelerate the transfer of photo-generated electron on the surface of CdS, thus improving the charge utilization efficiency. Meanwhile, CoP and 1T-MoS2 as active sites can also promote the water dissociation and lower the H+ reduction overpotential, thus contributing to the excellent photocatalytic hydrogen production activity (23.59 mmol·h-1·g-1 and 1195.8 mol·h-1·g-1 for CdS/CoP and CdS/1T-MoS2).

2.
Nanomaterials (Basel) ; 14(12)2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38921884

RESUMEN

Photocatalysis represents a sustainable strategy for addressing energy shortages and global warming. The main challenges in the photocatalytic process include limited light absorption, rapid recombination of photo-induced carriers, and poor surface catalytic activity for reactant molecules. Defect engineering in photocatalysts has been proven to be an efficient approach for improving solar-to-chemical energy conversion. Sulfur vacancies can adjust the electron structure, act as electron reservoirs, and provide abundant adsorption and activate sites, leading to enhanced photocatalytic activity. In this work, we aim to elucidate the role of sulfur vacancies in photocatalytic reactions and provide valuable insights for engineering high-efficiency photocatalysts with abundant sulfur vacancies in the future. First, we delve into the fundamental understanding of photocatalysis. Subsequently, various strategies for fabricating sulfur vacancies in photocatalysts are summarized, along with the corresponding characterization techniques. More importantly, the enhanced photocatalytic mechanism, focusing on three key factors, including electron structure, charge transfer, and the surface catalytic reaction, is discussed in detail. Finally, the future opportunities and challenges in sulfur vacancy engineering for photocatalysis are identified.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38000290

RESUMEN

Natural products provide a new opportunity for the discovery of neuraminidase (NA)inhibitors. In this study, an affinity ultrafiltration (AUF) coupled with HPLC-MS/MS method was firstly developed and optimized for screening of NA inhibitors from natural products. The critical factors influencing the interaction of enzyme-ligand (including sample concentration, enzyme concentration, incubation time and temperature, pH of the buffer, and dissociation solvents and time) were investigated and optimized by a one-factor-at-a-time design. The method was then applied to discover NA inhibitory compounds in stems and leaves of Baphicacanthus cusia. As a result, five active alkaloids were screened out and identifiedas 2,4(1H,3H)-quinazolinedione (1), 4(3H)-quinazolinone (2), 2(3H)-benzoxazolone (3), tryptanthrin (4), and indirubin (5) through analysis of their DAD profiles, MS/MS fragments, and comparison with reference substances. These active compounds were further evaluated for their NA inhibitory activity using a fluorescence-based NA inhibition assay. The result from the fluorescent assay revealed that all the five compounds(1-5) showed pronounced NA inhibitory activities with IC50values of 98.98, 64.69, 40.16, 69.44, and 144.73 µM, respectively. Finally, molecular docking of these five alkaloids with NA showed that hydrogen bond and π-cation interactions dominated within the binding sites with binding energies ranging between -5.7 to -7.9 kcal/mol, which was supported by the results of the AUF and the fluorescence-based enzyme assay. The developed AUF method is simple and efficient for screening potential NA inhibitors from stems and leaves of B. cusia.


Asunto(s)
Alcaloides , Espectrometría de Masas en Tándem , Simulación del Acoplamiento Molecular , Neuraminidasa , Ultrafiltración/métodos , Inhibidores Enzimáticos/análisis , Extractos Vegetales/química , Colorantes
4.
Braz J Otorhinolaryngol ; 89(6): 101331, 2023 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-37782990

RESUMEN

OBJECTIVE(S): In this study, the laryngopharynx microbiome alterations were characterized after proton pump inhibitor treatment in patients with Laryngopharyngeal Reflux Disease (LPRD) and healthy people. The potential outcome-predictive biomarker was explored. METHODS: Patients with LPRD and healthy controls were enrolled. The composition of their laryngopharynx microbiota was analyzed both by traditional plate count of the main bacterial groups and PCR amplification followed by denaturing gradient gel electrophoresis. Shannon-Wiener index and evenness index based on Dice index were used to assess the bacterial diversity. Droplet digital PCR was used to determine the total bacterial RNA and relative abundance of Klebsiella oxytoca. Receiver operating characteristic curve was plotted to explore the potential of Klebsiella oxytoca as an outcome-predictive biomarker. RESULTS: A total of 29 LPRD cases and 28 healthy subjects were enrolled. The composition of the laryngopharynx microbiota was almost similar, except Klebsiella oxytoca. The cluster analysis showed that the similarity between healthy and treatment-effective groups, as well as pretreatment and treatment-invalid groups, was close. Statistical analysis showed that there were differences in the diversity index and richness among the healthy, treatment-effective, pretreatment and treatment-invalid groups. The abundance of Klebsiella oxytoca in the treatment-effective LPRD group was lower than that of the treatment-invalid LPRD group. The abundance of Klebsiella oxytoca can distinguish treatment-effective and -invalid groups (AUC=0.859) with a sensitivity of 77.78% and specificity of 90.91%. CONCLUSION: There were differences in the diversity of cecal contents microbial community between treatment-invalid and treatment-effective LPRD groups. Klebsiella oxytoca has potential to distinguish treatment outcomes. LEVEL OF EVIDENCE: How common is the problem? Level 1. Is this diagnostic or monitoring test accurate? (Diagnosis) Level 4. What will happen if we do not add a therapy? (Prognosis) Level 5. Does this intervention help? (Treatment Benefits) Level 4. What are the COMMON harms? (Treatment Harms) Level 4. What are the RARE harms? (Treatment Harms) Level 4. Is this (early detection) test worthwhile?(Screening) Level 4.

5.
Braz. j. otorhinolaryngol. (Impr.) ; 89(6): 101331, Jan.-Feb. 2023. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1528110

RESUMEN

Abstract Objective(s): In this study, the laryngopharynx microbiome alterations were characterized after proton pump inhibitor treatment in patients with Laryngopharyngeal Reflux Disease (LPRD) and healthy people. The potential outcome-predictive biomarker was explored. Methods: Patients with LPRD and healthy controls were enrolled. The composition of their laryngopharynx microbiota was analyzed both by traditional plate count of the main bacterial groups and PCR amplification followed by denaturing gradient gel electrophoresis. Shannon-Wiener index and evenness index based on Dice index were used to assess the bacterial diversity. Droplet digital PCR was used to determine the total bacterial RNA and relative abundance of Klebsiella oxytoca. Receiver operating characteristic curve was plotted to explore the potential of Klebsiella oxytoca as an outcome-predictive biomarker. Results: A total of 29 LPRD cases and 28 healthy subjects were enrolled. The composition of the laryngopharynx microbiota was almost similar, except Klebsiella oxytoca. The cluster analysis showed that the similarity between healthy and treatment-effective groups, as well as pretreatment and treatment-invalid groups, was close. Statistical analysis showed that there were differences in the diversity index and richness among the healthy, treatment-effective, pretreatment and treatment-invalid groups. The abundance of Klebsiella oxytoca in the treatment-effective LPRD group was lower than that of the treatment-invalid LPRD group. The abundance of Klebsiella oxytoca can distinguish treatment-effective and -invalid groups (AUC = 0.859) with a sensitivity of 77.78% and specificity of 90.91%. Conclusion: There were differences in the diversity of cecal contents microbial community between treatment-invalid and treatment-effective LPRD groups. Klebsiella oxytoca has potential to distinguish treatment outcomes. Level of evidence: How common is the problem? Level 1. Is this diagnostic or monitoring test accurate? (Diagnosis) Level 4. What will happen if we do not add a therapy? (Prognosis) Level 5. Does this intervention help? (Treatment Benefits) Level 4. What are the COMMON harms? (Treatment Harms) Level 4. What are the RARE harms? (Treatment Harms) Level 4. Is this (early detection) test worthwhile?(Screening) Level 4.

6.
Insects ; 13(9)2022 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-36135535

RESUMEN

A neuropeptide precursor encoded by Bta06987 associates with AKH neuropeptide. In the AKH/RPCH family, these members have been demonstrated to participate in energy mobilization in many insects. In our research, the Bta06987 gene from Bemisia tabaci was cloned, and the amino acid sequence analysis was performed. During the starvation of B. tabaci, the mRNA level of Bta06987 showed a significant elevation. We investigated the functions of Bta06987 in B. tabaci using RNA interference (RNAi), and the adult females of B. tabaci after being fed with dsBta06987 showed a higher glycogen and triglyceride levels and lower trehalose content than the control. Furthermore, in the electrical penetration graph (EPG) experiment, B. tabaci showed changes in feeding behavior after feeding with dsBta06987, such as the reduction in parameters of E waveform percentage and total feeding time. Our findings might be helpful in developing strategies to control pest and plant virus transmission.

7.
Biochem Biophys Res Commun ; 534: 401-407, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33248692

RESUMEN

Otitis media with effusion (OME) is the major cause of hearing impairment in children. miR-210 plays a critical role in inflammatory diseases, however, its role in OME is unknown. In this study, the miR-210 level in serum and middle ear effusion of is significantly down-regulated in serum, middle ear effusion from OME patients (100 cases) compared with healthy volunteers (50 cases). The expression of miR-210 is closely related to inflammatory factors and bone conduction disorder in patients with OME. In the in vitro study,the miR-210 level is significantly reduced in culture supernatant of lipopolysaccharide (LPS) treated human middle ear epithelial cells (HMEECs). miR-210 overexpression inhibited the LPS-induced in inflammatory cytokines production, cell viability reduction and cell apoptosis. Bioinformatics and dual-luciferase reporter assay showed that HIF-1a was a target gene of miR-210. The biological effects of miR-210 on cell viability, cell apoptosis and inflammation cytokines in LPS-induced HMEECs were reversed by HIF-1a overexpression. Furthermore, phosphorylation of NF-κB p65 was significantly decreased by miR-210 mediated HIF-1a in LPS-induced HMEECs. This study suggested that miR-210 may play a role in OME. Further studies are warranted to assess miR-210 as a potential target for the diagnosis and treatment of OME.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , MicroARNs/genética , Otitis Media con Derrame/genética , Adolescente , Apoptosis/genética , Conducción Ósea/genética , Conducción Ósea/fisiología , Estudios de Casos y Controles , Supervivencia Celular/genética , Células Cultivadas , Niño , Regulación hacia Abajo , Oído Medio/metabolismo , Oído Medio/patología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Inflamación/genética , Inflamación/metabolismo , Inflamación/patología , Masculino , MicroARNs/sangre , MicroARNs/metabolismo , Otitis Media con Derrame/metabolismo , Otitis Media con Derrame/patología , Adulto Joven
8.
Oncol Lett ; 17(6): 5653-5661, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31186788

RESUMEN

The human ether-a-go-go-related potassium channel 1 (hERG1) is a functional component of the voltage-gated Kv11.1 potassium channel, which is commonly described as a crucial factor in the tumorigenesis of a variety of tumors. Ovarian cancer is one of the most severe types of cancer, with an extremely poor prognosis. Advances have been made in recent years; however, drug resistance and tumor recurrence remain critical issues underlying satisfactory treatment outcomes. Therefore, more effective antitumor agents with low levels of drug resistance for ovarian cancer treatment are urgently required in clinical practice. In the present study, hERG1 mRNA expression in ovarian tumor tissues and cell lines were measured by reverse transcription-quantitative polymerase chain reaction. Immunohistochemistry and western blotting were used to assess the expression levels of hERG1 protein. Cell proliferation, migration and invasion were assessed by Cell Counting Kit-8 assay and Transwell assay. A tumor xenograft assay was used to determine the growth of tumors in vivo. It was demonstrated that the expression levels of hERG1 were significantly elevated in ovarian cancer tissues and expressed in ovarian cancer cell lines, particularly in SKOV3 cells. Abnormal hERG1 expression was significantly associated with the proliferation, migration and invasion abilities of ovarian cancer. In addition, berberine (BBR) may be used as a potential drug in the treatment of ovarian cancer, possibly due to its inhibitory effects on the hERG1 channels. In conclusion, the present study demonstrated that hERG1 may be a potential therapeutic target in the treatment of ovarian cancer and provided novel insights into the mechanism underlying the antitumor effects of BBR in ovarian cancer.

9.
Oncol Rep ; 41(3): 1875-1882, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30628719

RESUMEN

Xeroderma pigmentosum, complementation group C (XPC) is an accessory recognition gene involved in the nucleotide excision repair (NER) pathway, which is activated during the initial DNA damage recognition stage. It participates in the regulation of DNA damage­induced proliferation and apoptosis. Emerging evidence demonstrates that upregulation of XPC increases the resistance of several tumor cell types to cytotoxic drugs. In addition, it can predict poor patient outcome for non­small cell lung cancer (NSCLC). However, the mechanisms linking upregulation of XPC and drug resistance in lung cancer are still unclear. In the present study, we aimed to confirm whether XPC was involved in the reversal of the cisplatin (DDP) resistance in drug­resistant A549/DDP lung adenocarcinoma cells. RT­PCR and western blot assays were used to examine XPC mRNA and protein expression levels. Cell viability was assessed by CCK­8 assay. The knockdown of XPC was achieved in A549/DDP cells using si­RNA, whereas cell proliferation and apoptosis were assessed by wound healing assay and flow cytometric analysis, respectively. The median inhibitory concentration (IC50) value of DDP was assessed by CCK­8 assay. Western blot assays were conducted for the examination of caspase­9/3, Bax and Bcl­2 protein levels, whereas the activation of the PI3K/Akt/mTOR signaling pathway was investigated in XPC­knockdown cells. High expression of XPC was noted in A549/DDP cells compared with that in A549 cells, which was associated with DDP resistance. XPC silencing significantly inhibited A549/DDP cell proliferation and increased the induction of apoptosis. In addition, XPC knockdown decreased the expression levels of the Akt/mTOR signaling proteins and the expression of their downstream mediator. The data of the present study revealed that XPC inhibition rescued DDP resistance in lung adenocarcinoma cells, which was dependent on the Akt/mTOR signaling pathway. Collectively, XPC may be considered a new strategy for curing DDP­resistant lung cancer and may improve the efficacy of conventional chemotherapy.


Asunto(s)
Adenocarcinoma del Pulmón/tratamiento farmacológico , Cisplatino/farmacología , Proteínas de Unión al ADN/metabolismo , Resistencia a Antineoplásicos , Neoplasias Pulmonares/tratamiento farmacológico , Células A549 , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Apoptosis/efectos de los fármacos , Apoptosis/genética , Proliferación Celular/efectos de los fármacos , Proliferación Celular/genética , Cisplatino/uso terapéutico , Daño del ADN/efectos de los fármacos , Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Técnicas de Silenciamiento del Gen , Humanos , Concentración 50 Inhibidora , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/metabolismo , ARN Interferente Pequeño/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Regulación hacia Arriba
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