Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nanomedicine ; 40: 102491, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34781040

RESUMO

We previously reported that co-delivery of dihydroartemisinin and high mobility group box 1 (HMGB1) siRNAs, using cell penetrating peptide (TAT)-modified cationic liposomes (TAT-CLs-DHA/siRNA), resulted in promising activity for the treatment of inflammatory disease through TLR4 signaling pathway. In the current study, we further investigated the therapeutic effects of TAT-CLs-DHA/siRNA on lupus-prone MRL/lpr mice and explored its effects on B cell responses. In vitro, we found that TAT-CLs-DHA/siRNA suppressed the proliferation and activation of B cells through the TLR4 signaling pathway. Following parenteral administration every 4 days, TAT-CLs-DHA/siRNA significantly reduced proteinuria, glomerulonephritis, serum anti-dsDNA antibody and secretion of interleukin (IL)-6, IL-10, IL-17 and IL-21. Moreover, Western blotting showed that TAT-CLs-DHA/siRNA modulated the B-cell intrinsic pathway by downregulating expression of HMGB1, TLR4, MyD88 and NF-κB. This co-delivery system thus represents a promising treatment option for lupus nephritis, and also highlights a novel target of lupus treatment through B cell TLR4 signal pathway.


Assuntos
Nefrite Lúpica , Receptor 4 Toll-Like , Animais , Anticorpos Antinucleares , Lipossomos , Nefrite Lúpica/tratamento farmacológico , Nefrite Lúpica/metabolismo , Camundongos , Camundongos Endogâmicos MRL lpr , Receptor 4 Toll-Like/metabolismo
2.
Small ; 13(24)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28489315

RESUMO

Formation of 3D mesostructures in advanced functional materials is of growing interest due to the widespread envisioned applications of devices that exploit 3D architectures. Mechanically guided assembly based on compressive buckling of 2D precursors represents a promising method, with applicability to a diverse set of geometries and materials, including inorganic semiconductors, metals, polymers, and their heterogeneous combinations. This paper introduces ideas that extend the levels of control and the range of 3D layouts that are achievable in this manner. Here, thin, patterned layers with well-defined residual stresses influence the process of 2D to 3D geometric transformation. Systematic studies through combined analytical modeling, numerical simulations, and experimental observations demonstrate the effectiveness of the proposed strategy through ≈20 example cases with a broad range of complex 3D topologies. The results elucidate the ability of these stressed layers to alter the energy landscape associated with the transformation process and, specifically, the energy barriers that separate different stable modes in the final 3D configurations. A demonstration in a mechanically tunable microbalance illustrates the utility of these ideas in a simple structure designed for mass measurement.


Assuntos
Nanoestruturas/química , Polímeros/química , Impressão Tridimensional
3.
Adv Funct Mater ; 26(16): 2629-2639, 2016 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-27499727

RESUMO

Origami is a topic of rapidly growing interest in both the scientific and engineering research communities due to its promising potential in a broad range of applications. Previous assembly approaches of origami structures at the micro/nanoscale are constrained by the applicable classes of materials, topologies and/or capability of control over the transformation. Here, we introduce an approach that exploits controlled mechanical buckling for autonomic origami assembly of 3D structures across material classes from soft polymers to brittle inorganic semiconductors, and length scales from nanometers to centimeters. This approach relies on a spatial variation of thickness in the initial 2D structures as an effective strategy to produce engineered folding creases during the compressive buckling process. The elastic nature of the assembly scheme enables active, deterministic control over intermediate states in the 2D to 3D transformation in a continuous and reversible manner. Demonstrations include a broad set of 3D structures formed through unidirectional, bidirectional, and even hierarchical folding, with examples ranging from half cylindrical columns and fish scales, to cubic boxes, pyramids, starfish, paper fans, skew tooth structures, and to amusing system-level examples of soccer balls, model houses, cars, and multi-floor textured buildings.

4.
Biomed Pharmacother ; 175: 116776, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38788546

RESUMO

Choroidal neovascularization (CNV), characterized as a prominent feature of wet age-related macular degeneration (AMD), is a primary contributor to visual impairment and severe vision loss globally, while the prevailing treatments are often unsatisfactory. The development of conventional treatment strategies has largely been based on the understanding that the angiogenic switch of endothelial cells is dictated by angiogenic growth factors alone. Even though treatments targeting vascular endothelial growth factor (VEGF), like Ranibizumab, are widely administered, more than half of the patients still exhibit inadequate or null responses, emphasizing the imperative need for solutions to this problem. Here, aiming to explore therapeutic strategies from a novel perspective of endothelial cell metabolism, a biocompatible nanomedicine delivery system is constructed by loading RGD peptide-modified liposomes with 2-deoxy-D-glucose (RGD@LP-2-DG). RGD@LP-2-DG displayed good targeting performance towards endothelial cells and excellent in vitro and in vivo inhibitory effects on neovascularization were demonstrated. Moreover, our mechanistic studies revealed that 2-DG interfered with N-glycosylation, leading to the inhibition of vascular endothelial growth factor receptor 2 (VEGFR2) and its downstream signaling. Notably, the remarkable inhibitory effect on neovascularization and biocompatibility of RGD@LP-2-DG render it a highly promising and clinically translatable therapeutic candidate for the treatment of wet AMD and other angiogenic diseases, particularly in patients who are unresponsive to currently available treatments.


Assuntos
Neovascularização de Coroide , Desoxiglucose , Lipossomos , Nanomedicina , Oligopeptídeos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular , Degeneração Macular Exsudativa , Oligopeptídeos/química , Animais , Humanos , Nanomedicina/métodos , Neovascularização de Coroide/tratamento farmacológico , Neovascularização de Coroide/patologia , Neovascularização de Coroide/metabolismo , Degeneração Macular Exsudativa/tratamento farmacológico , Degeneração Macular Exsudativa/metabolismo , Desoxiglucose/farmacologia , Desoxiglucose/administração & dosagem , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo
5.
Int J Nanomedicine ; 14: 8627-8645, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31806961

RESUMO

BACKGROUND AND PURPOSE: Systemic lupus erythematous (SLE) is an autoimmune disease caused by many factors. Lupus nephritis (LN) is a common complication of SLE and represents a major cause of morbidity and mortality. Previous studies have shown the advantages of multi-targeted therapy for LN and that TLR4 signaling is a target of anti-LN drugs. High-mobility group box 1 (HMGB1), a nuclear protein with a proinflammatory cytokine activity, binds specifically to TLR4 to induce inflammation. We aimed to develop PEGylated TAT peptide-cationic liposomes (TAT-CLs) to deliver anti-HMGB1 siRNA and dihydroartemisinin (DHA) to increase LN therapeutic efficiency and explore their treatment mechanism. METHODS: We constructed the TAT-CLs-DHA/siRNA delivery system using the thin film hydration method. The uptake and localization of Cy3-labeled siRNA were detected by confocal microscopy and flow cytometry. MTT assays were used to detect glomerular mesangial cell proliferation. Real-time PCR, Western blot analysis, and ELISA evaluated the anti-inflammatory mechanism of TAT-CLs-DHA/siRNA. RESULTS: We constructed the TAT-CLs-DHA/siRNA delivery system measuring approximately 140 nm with superior storage and serum stabilities. In vitro, it showed significantly greater uptake compared with unmodified liposomes and significant inhibition of glomerular mesangial cell proliferation. TAT-CLs-DHA/siRNA inhibited NF-κB activation in a concentration-dependent manner. Real-time PCR and Western blot analysis showed that TAT-CLs-DHA/siRNA downregulated expression of HMGB1 mRNA and protein. TAT-CLs-DHA/siRNA markedly diminished Toll-like receptor 4 (TLR4) expression and subsequent activation of MyD88, IRAK4, and NF-κB. CONCLUSION: TAT-CLs-DHA/siRNA may have the potential for treatment of inflammatory diseases such as LN mediated by the TLR4 signaling pathway.


Assuntos
Artemisininas/administração & dosagem , Produtos do Gene tat/genética , Proteína HMGB1/genética , Lipossomos/administração & dosagem , Nefrite Lúpica/terapia , RNA Interferente Pequeno/administração & dosagem , Receptor 4 Toll-Like/metabolismo , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Lipossomos/química , Lipossomos/farmacologia , Nefrite Lúpica/metabolismo , NF-kappa B/metabolismo , RNA Interferente Pequeno/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
6.
Carbohydr Polym ; 98(1): 1002-10, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23987440

RESUMO

Novel composites based on borassus fruit fine fiber (BFF) and polypropylene (PP) were fabricated with variable fiber composition (5, 10, 15 and 20 wt%) by injection molding. Maleated PP (MAPP) was also used as compatibilizer at 5 wt% for effective fiber-matrix adhesion. FTIR analysis confirms the evidence of a chemical bonding between the fiber and polymeric matrix through esterification in presence of MAPP. The tensile and flexural properties were found to increase with 15 and 10 wt% fiber loadings respectively, and decreased thereafter. Coir, jute and sisal fiber composites were also fabricated with 15 wt% fiber loading under the same conditions as used for BFF/PP composites. It was found that the mechanical properties of BFF (15 wt%)/PP composites were equivalent to jute/PP, sisal/PP and superior to coir/PP composites. Jute/PP and sisal/PP composites showed higher water absorption than BFF/PP and coir/PP composites. These results have demonstrated that the BFF/PP composites can also be an alternative material for composites applications.


Assuntos
Agave/química , Cocos/química , Corchorus/química , Frutas/química , Lignina/química , Polipropilenos/química , Absorção , Maleatos/química , Temperatura , Resistência à Tração , Água/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA