Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 8 de 8
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
J Colloid Interface Sci ; 662: 192-207, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38341942

RESUMO

HYPOTHESIS: Two major protein families are present in rapeseed, namely cruciferins and napins. The structural differences between the two protein families indicate that they might behave differently when their mixture stabilises oil-water interfaces. Therefore, this work focuses on elucidating the role of both proteins in interface and emulsion stabilisation. EXPERIMENTS: Protein molecular properties were evaluated, using SEC, DSC, CD, and hydrophobicity analysis. The oil-water interface mechanical properties were studied using LAOS and LAOD. General stress decomposition (GSD) was used as a novel method to characterise the nonlinear response. Additionally, to evaluate the emulsifying properties of the rapeseed proteins, emulsions were prepared using pure napins or cruciferin and also their mixtures at 1:3, 1:1 and 3:1 (w:w) ratios. FINDINGS: Cruciferins formed stiff viscoelastic solid-like interfacial layers (Gs' = 0.046 mN/m; Ed' = 30.1 mN/m), while napin formed weaker and more stretchable layers at the oil-water interface (Gs' = 0.010 mN/m; Ed' = 26.4 mN/m). As a result, cruciferin-formed oil droplets with much higher stability against coalescence (coalescence index, CI up to 10%) than napin-stabilised ones (CI up to 146%) during two months of storage. Both proteins have a different role in emulsions produced with napin-cruciferin mixtures, where cruciferin provides high coalescence stability, while napin induces flocculation. Our work showed the role of each rapeseed protein in liquid-liquid multiphase systems.


Assuntos
Brassica napus , Brassica rapa , Brassica napus/química , Emulsões/química , Reologia , Água/química
2.
J Org Chem ; 88(24): 17284-17296, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38054778

RESUMO

The selective functionalization of trifluoromethyl groups through C-F cleavage poses a significant challenge due to the high bond energy of the C(sp3)-F bonds. Herein, we present dihydroacridine derivatives as photocatalysts that can functionalize the C-F bond of trifluoromethyl groups with various alkenes under mild conditions. Mechanistic studies and DFT calculations revealed that upon irradiation, the dihydroacridine derivatives exhibit high reducibility and function as photocatalysts for reductive defluorination. This process involves a sequential single-electron transfer mechanism. This research provides valuable insights into the properties of dihydroacridine derivatives as photocatalysts, highlighting the importance of maintaining a planar conformation and a large conjugated system for optimal catalytic activity. These findings facilitate the efficient catalytic reduction of inert chemical bonds.

3.
Adv Sci (Weinh) ; 10(34): e2303734, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37814361

RESUMO

Two-dimensional material-based field-effect transistors (2DM-FETs) are playing a revolutionary role in electronic devices. However, before electronic design automation (EDA) for 2DM-FETs can be achieved, it remains necessary to determine how to incorporate contact transports into model. Reported methods compromise between physical intelligibility and model compactness due to the heterojunction nature. To address this, quasi-Fermi-level phase space theory (QFLPS) is generalized to incorporate contact transports using the Landauer formula. It turns out that the Landauer-QFLPS model effectively overcomes the issue of concern. The proposed new formula can describe 2DM-FETs with Schottky or Ohmic contacts with superior accuracy and efficiency over previous methods, especially when describing non-monotonic drain conductance characteristics. A three-bit threshold inverter quantizer (TIQ) circuit is fabricated using ambipolar black phosphorus and it is demonstrated that the model accurately predicts circuit performance. The model could be very effective and valuable in the development of 2DM-FET-based integrated circuits.

4.
Nano Lett ; 23(7): 2964-2973, 2023 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36947431

RESUMO

Recent advances in intratracheal delivery strategies have sparked considerable biomedical interest in developing this promising approach for lung cancer diagnosis and treatment. However, there are very few relevant studies on the behavior and mechanism of imaging nanoparticles (NPs) after intratracheal delivery. Here, we found that nanosized perfluoro-15-crown-5-ether (PFCE NPs, ∼200 nm) exhibite significant 19F-MRI signal-to-noise ratio (SNR) enhancement than perfluorooctyl bromide (PFOB NPs) up to day 7 after intratracheal delivery. Alveolar macrophages (AMs) engulf PFCE NPs, become PFCE NPs-laden AMs, and then migrate into the tumor margin, resulting in increased tumor PFCE concentration and 19F-MRI signals. AMs-mediated translocation of PFCE NPs to lung draning lymph nodes (dLNs) decreases the background PFCE concentration. Our results shed light on the dynamic AMs-mediated translocation of intratracheally delivered PFC NPs for effective lung tumor visualization and reveal a pathway to develop and promote the clinical translation of an intratracheal delivery-based imaging strategy.


Assuntos
Fluorocarbonos , Neoplasias Pulmonares , Nanopartículas , Humanos , Macrófagos Alveolares , Imageamento por Ressonância Magnética/métodos , Neoplasias Pulmonares/tratamento farmacológico
5.
Food Chem ; 398: 133851, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35963217

RESUMO

Modulating the size and surface charge of nanocarriers provides an efficacious strategy to enhance bioavailability of encapsulated cargos through increased mucus penetration. In this study, mucus-permHeable soy protein nanoparticles (SPNPs) were successfully fabricated via gastrointestinal proteolysis coupled with heating and pH-shifting treatment. Results showed that treatment at 65 °C and 75 °C after proteolysis induced the assembly of α, ά, and ß subunits, forming a relatively loose structure. This facilitated further assembly upon pH-shifting, forming smaller-sized and less electronegative nanoparticles, which showed enhanced mucus permeability. However, treatment at 85 °C and 95 °C promoted stronger hydrophobic interactions and induced disulfide bond cross-linking between B and ß subunits, forming compact macro-aggregates with high ß-sheet structure. These larger-sized aggregates were less influenced by pH-shifting treatment, demonstrating limited mucus diffusion. This study provides a potential alternative to fabricate mucus-permeable nanoparticles, and established a relationship between protein subunit assembly behavior and its mucus permeability.


Assuntos
Nanopartículas , Proteínas de Soja , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Hidrólise , Muco/metabolismo , Nanopartículas/química , Proteínas de Soja/química
6.
Food Chem ; 383: 132489, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35183964

RESUMO

Pickering emulsions prepared by food-grade particles have gained growing attention due to their promising application in functional food and pharmaceutical industries. In this study, we successfully fabricated soy peptide-based nanoparticles (SPN) through pH-driven process. Obtained particles with small particle size were surface active and shared intermediate wettability, and they could be well applied as an efficient particulate emulsifier for stabilizing oil-in-water Pickering emulsions at SPN concentration above 0.25 wt%. Furthermore, formed emulsions stabilized with SPN exhibited good protection towards Vitamin D3 against UV irradiation and oxidative deterioration, where controlled release of Vitamin D3in vitro could also be well achieved by modulating particle concentration. The whole process can contribute to a sustainable development of low-value peptide byproducts as functional food ingredients.


Assuntos
Colecalciferol , Nanopartículas , Emulsificantes , Emulsões , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Peptídeos , Água
7.
Cancer Lett ; 522: 105-118, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34343636

RESUMO

Ceramide synthases (CerSs) catalyze the formation of ceramides from sphingoid bases and acyl-CoA substrates. Increasing evidence suggests that cancer cells generally exhibit altered sphingolipid metabolism in the tumorigenesis of multiple cancers. However, there is no evidence that CerSs are associated with pancreatic ductal carcinoma (PDAC). In the present study, we examined CerS expression in clinical tissue and conducted data mining to investigate the clinical significance of CerSs in the TCGA-PAAD database. We found that high CerS6 expression positively correlated with progression and predicted worse prognosis in PDAC patients, establishing CerS6 as a potential biomarker for PDAC. Furthermore, CerS6 promoted cell proliferation, colony formation and invasion by producing C16-ceramide and was required for tumor formation. Mechanistically, AKT1 interacted with and phosphorylated FOXP3 at S418, which decreased the binding of FOXP3 to the CERS6 promoter and in turn induced CerS6 expression by reconstituting an activated state on the CERS6 promoter. The AKT1/FOXP3 axis mediated the CerS6 expression and promoted p53 mutant pancreatic tumorigenesis by producing excessive C16-ceramide, which induced the accumulation of mutant p53. Thus, our study explores the relationship between PI3K/AKT signaling and sphingolipid metabolism, revealing an oncogenic role for CerS6, which may represent a potential target for PDAC treatment.


Assuntos
Carcinoma Ductal Pancreático/genética , Fatores de Transcrição Forkhead/genética , Proteínas de Membrana/genética , Neoplasias Pancreáticas/genética , Esfingosina N-Aciltransferase/genética , Proteína Supressora de Tumor p53/genética , Apoptose/genética , Carcinogênese/genética , Carcinoma Ductal Pancreático/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Mutação , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas c-akt/genética
8.
Food Chem ; 355: 129509, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-33813157

RESUMO

The insoluble soy peptide aggregates formed upon proteolysis are generally considered as "ready to be discarded", which placed additional burden on related industries. In this study, with the aim of promoting sustainable utilization of these large aggregates, novel soy peptide-based nanoparticles (SPN) were successfully fabricated from these aggregates via a controlled pH-shifting method, and the obtained SPN exhibited good storage stability and antioxidant activity. Furthermore, the pH-shifting process also provided a driven force for loading and delivering curcumin, which significantly improved its water solubility (up to 105 folds), storage and simulated gastric-intestinal digestive stability, as well as in vitro bioavailability and antioxidant activity. These results indicated that controlled pH-shifting could be an effective and facile method to trigger the assembly of insoluble aggregates into functional peptide nanoparticles for the delivery of bioactive cargoes, which provided a new strategy for the sustainable and high-value application of these low-value peptide byproducts.


Assuntos
Portadores de Fármacos/química , Nanopartículas/química , Peptídeos/química , Agregados Proteicos , Proteínas de Soja/química , Antioxidantes/química , Disponibilidade Biológica , Curcumina/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Tamanho da Partícula , Solubilidade
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA