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

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Small ; : e2312209, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38530091

RESUMO

Developing novel proton exchange membranes (PEMs) with low cost and superior performance to replace Nafion is of great significance. Polyoxometalate-doped sulfonated poly(aryl ether ketone sulfone) (SPAEKS) allows for the amalgamation of the advantages in each constituent, thereby achieving an optimized performance for the hybrid PEMs. Herein, the hybrid membranes by introducing 2MeIm-{Mo132} into SPAEKS are obtained. Excellent hydrophilic properties of 2MeIm-{Mo132} can help more water molecules be retained in the hybrid membrane, providing abundant carriers for proton transport and proton hopping sites to build successive hydrophilic channels, thus lowering the energy barrier, accelerating the proton migration, and significantly fostering the proton conductivity of hybrid membranes. Especially, SP-2MIMo132-5 exhibits an enhanced proton conductivity of 75 mS cm-1 at 80 °C, which is 82.9% higher than pristine SPAEKS membrane. Additionally, this membrane is suitable for application in proton exchange membrane fuel cells, and a maximum power density of 266.2 mW cm-2 can be achieved at 80 °C, which far exceeds that of pristine SPAEKS membrane (54.6 mW cm-2). This work demonstrates that polyoxometalate-based clusters can serve as excellent proton conduction sites, opening up the choice of proton conduction carriers in hybrid membrane design and providing a novel idea to manufacture high-performance PEMs.

3.
ESC Heart Fail ; 10(5): 3028-3037, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37563882

RESUMO

AIMS: In this study, we aimed to develop and validate a competing risk nomogram for predicting cardiac death and heart transplantation (HT) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). METHODS: We retrospectively enrolled 149 consecutive patients with ARVC diagnosed at our institution between 2008 and 2022. Cox proportional hazards model was primarily used to identify variables associated with cardiac death and HT. On the basis of these indicators, a competing risk nomogram was developed to predict the 1, 3, and 5 year probabilities of cardiac death and HT. The area under the receiver operating characteristic curve (AUC), Harrell's C-index, and calibration curves were used to evaluate and internally validate the performance of the model. Decision curve analysis was performed to assess the clinical utility of the nomogram. RESULT: Of the 149 patients with ARVC, the mean age was 38.77 ± 15.94 years, and most of the patients were men (67.11%, 100/149). Fourteen patients experienced cardiac death and nine underwent HT, during a median follow-up period of 5.8 years (interquartile range, 0.62-5.56 years). Multivariable COX analysis revealed that extent of TWI in the anterior and inferior leads (P = 0.0057), right atrial diameter on transthoracic echocardiography (P = 0.0498), RVEF (P = 0.1036), and LVEF (P < 0.001) all showed statistical significance. The 1-, 3-, and 5-year cumulative incidence of cardiac death and HT were 3.35%, 8.05%, and 11.4%, respectively. The area under the receiver operating characteristic curve of the nomogram for predicting cardiac death and HT at 1, 3, and 5 years after diagnosis of ARVC were 0.860, 0.935, and 0.956. The value of Harrell's C-index is 0.9273 (95% confidence interval 0.8954-0.9590; P < 0.001), indicating that the model had good discriminative ability in internal validation. Decision curve analysis revealed that our model was clinically useful within the entire range of potential treatment thresholds in most cases. The cumulative incidence of the primary outcomes was significantly different between the three risk groups according to nomogram-derived scores (P < 0.001). CONCLUSIONS: On the basis of a retrospective review of patients with ARVC at a single centre, we developed a novel nomogram for predicting the risk of cardiac death and HT after ARVC diagnosis. This competing risk nomogram based on four readily available clinical parameters (right atrial diameter, right and left ventricular ejection fraction, and T-wave inversion) is a potentially useful tool for individualized prognostic assessment in patients with ARVC.

4.
Chem Biodivers ; 20(9): e202300006, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37565513

RESUMO

This study investigated the impact of ultrasonic extraction (UE) on the structure and in vitro antibacterial activity of polysaccharides from sugarcane leaves (SLW). Native sugarcane leaf polysaccharides were treated with ultrasound (480 W) for 3 h to yield sugarcane leaf polysaccharides (SLU). Compared to SLW (33.59 kDa), the molecular weight of SLU (13.08 kDa) was significantly decreased, while the monosaccharide composition of SLU was unchanged. The results of SEM and XRD indicated that UE significantly changed the surface morphology of SLW and destroyed its inner crystalline structure. In vitro experiments showed that SLU had stronger antibacterial activity. These findings revealed that UE treatment could alter the tertiary structure of SLW but had no impact on its primary structure. Furthermore, the antibacterial activity of SLW could be greatly enhanced after UE treatment. As a bioactive additive, SLU has great application potential in functional foods, cosmetics, and pharmaceuticals.


Assuntos
Saccharum , Ultrassom , Polissacarídeos/farmacologia , Polissacarídeos/química , Antioxidantes/química , Folhas de Planta , Antibacterianos/farmacologia , Ondas Ultrassônicas
5.
Ultrason Sonochem ; 99: 106549, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37574641

RESUMO

This study firstly used sugarcane leaf polyphenols (SGLp) to modify zein to form covalent nanoparticles (SGLpZ) and used SGLpZ as an emulsifier to stabilize pickering emulsions (SZP) via ultrasonic method. The results showed that the addition of SGLp could alter the physicochemical properties of zein, including improving increasing the hydrophilicity of zein and the antioxidant properties of zein (three basic antioxidant activities test in vitro). SGLpZ could be able to form a dense film on the surface of the pickering emulsions which inhibited lipid oxidation as the concentration of SGLp increased at 4 ℃ for 20 days, thus stabilizing pickering emulsions (SZP). Further assessment of storage stability of pickering emulsions stabilized by SGLp was evaluated via measuring the free fatty acids (FFA) release in vitro gastrointestinal digestion. The results showed that the FFA release of SZP decreased from 20.61 ± 0.10% to 16.14 ± 0.69%. In addition, SGLp gave SZP a yellow color, which inspired that SZP could be used in the food industry to make yellow-colored functional foods. Finally, the safety of SZP initially assessed by in-vitro hemocompatibility and cytotoxicity (MTT) assays. In conclusion, our fingdings were beneficial for the further design and development of SGLp in food fields and enabled the development a new type in functional protein-plant polyphenols food pickering emulsions.


Assuntos
Nanopartículas , Saccharum , Zeína , Emulsões/química , Antioxidantes/farmacologia , Antioxidantes/química , Zeína/química , Nanopartículas/química , Lipídeos/química , Digestão , Tamanho da Partícula
6.
Food Funct ; 14(11): 5012-5022, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37227321

RESUMO

In this study, sugarcane molasses essential oils (SMEOs) were extracted by microwave-assisted hydrodistillation (MAHD); the components of SMEOs were identified and analyzed by gas chromatography-mass spectrometry (GC-MS). SMEOs were loaded into mesoporous silica nanoparticles (MSNPs) and their sustained-release activity was evaluated. In vivo anti-inflammatory activity assays pertained to inhibiting the auricle swelling caused by xylene in mice, the peritoneal permeability increased inflammation in mice induced by acetic acid and the inflammation caused by granuloma hyperplasia in mice. We demonstrated that the main components of SMEOs were isoamylol, ethyl acetate, isobutanol, isovaleraldehyde, 2-methyl-butanal, furfural and 2-acetylpyrrole. The SMEOs loaded into MSNPs formed MSNP-SMEOs, which enhanced the stability and slow-release performance compared with SMEOs. The main components of SMEOs can inhibit inflammation, and the development and application of SMEOs in the fields of food and medicine have certain potential.


Assuntos
Nanopartículas , Óleos Voláteis , Saccharum , Animais , Camundongos , Óleos Voláteis/farmacologia , Óleos Voláteis/química , Melaço , Dióxido de Silício/química , Anti-Inflamatórios/farmacologia , Nanopartículas/química , Inflamação/tratamento farmacológico
7.
Food Res Int ; 163: 112141, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36596096

RESUMO

Proanthocyanidins have significant biological activity and pharmacological effects and are widely used in food, medicine, and cosmetics. Chitosan nanoparticles loaded with proanthocyanidins have been proven to improve their biological activity. Given some deficiencies of chitosan (CS), the modification of chitosan by folic acid (FA) can obtain new variants with different functions. For this objective, the folic acid conjugated chitosan was designed, and in vitro properties of proanthocyanidins loaded nanoparticles were studied systemically. Firstly, folic acid-chitosan conjugate (FA-CS) was synthesized and characterized. Folate-coupled chitosan-loaded proanthocyanidin nanoparticles (PC-CS/FA-NPs) were prepared by ionic gelation technique using FA-CS as a carrier. The successful nanoparticle synthesis was characterized by dynamic light scattering (DLS) techniques and Fourier transform infrared (FT-IR) spectroscopy. The synthesized nanoparticles exhibited a spherical shape and smooth and uniform distribution features with a size range of less than 300 nm, as observed by a scanning electron microscope (SEM). Meanwhile, PC-CS/FA-NPs had good thermal and gastrointestinal digestive stability and had a protective effect on AAPH-induced erythrocyte oxidative hemolysis. In conclusion, folic acid decorated chitosan nanoparticles improved the stability and bioavailability of proanthocyanidins in gastrointestinal digestion.


Assuntos
Quitosana , Nanopartículas , Proantocianidinas , Portadores de Fármacos/química , Quitosana/química , Ácido Fólico/química , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química , Digestão
8.
J Hazard Mater ; 399: 123004, 2020 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-32502858

RESUMO

This study presents comprehensive formation pathways of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) from the pyrolysis of polybrominated diphenyl ethers (PBDEs). A total of 23 PBDE congeners, from mono- to hepta- brominated, were selected to conduct the pyrolysis experiments. The results suggest that n-PBDEs (where n means the number of bromine substituents) can transform into n/(n-1) PBDFs and (n-1)/(n-2) PBDDs as long as they meet certain structural requirement. One single PBDE congener can only transform (if possible) specific PBDF or PBDD based on their specific brominated arrangement by direct/oxygen bridge connecting the two ortho-carbon atoms. Among all selected BDEs, we found that only 2,2',4,4',5,5'-hexaBDE (BDE-153) can transform into 2,3,7,8-tetraBDD, which is most toxic congener among these group of compounds. When the degree of bromination increased, the yield of polybromobenzene increased, while that of the PBDD/Fs decreased, suggesting that the higher PBDEs favors to break the ether bond to form polybromobenzene, while the lower PBDEs favor transformation into PBDD/Fs. We proposed that the results in this study greatly improved our understanding on the transformation of PBDD/Fs from PBDEs in the pyrolysis process.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA