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1.
Macromol Biosci ; 21(11): e2100202, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34405963

RESUMO

Glaucoma is an ophthalmic disease that is characterized by elevated intraocular pressure (IOP). Eye drops are the preferred choice to reduce IOP for the treatment of glaucoma. However, the bioavailability of eye drops is low (<5%). Their long-term frequent administration cannot ensure patient compliance, which is the main reason for treatment failure. Inspired by lollipop, herein, a multilayered sodium alginate-chitosan (SA-CS) hydrogel ball (HB) decorated by zinc oxide-modified biochar (ZnO-BC) is developed as a new drug delivery system. The multilayer structure encapsulate timolol maleate (TM) and levofloxacin inside the different layers to realize the sustained release of drugs, which can control ocular hypertension and prevent infection effectively. The results show that the release of TM can be sustained in vitro for longer than 2 weeks. Moreover, IOP is also effectively reduced in vivo. Meanwhile, the photothermal conversion activity of ZnO-BC can regulate drug release on demand after stimulation by near-infrared irradiation. More importantly, the designed HB also shows good biocompatibility and antibacterial properties in vitro and in vivo. In summary, ZnO-BC-SA-CS HB can effectively reduce IOP and is expected to replace the classical tedious eye drop strategy, having potential utilization value in the treatment of glaucoma.


Assuntos
Sistemas de Liberação de Medicamentos , Glaucoma/tratamento farmacológico , Hidrogéis/química , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Timolol/administração & dosagem , Animais , Humanos , Pressão Intraocular/efeitos dos fármacos , Soluções Oftálmicas , Coelhos , Timolol/farmacologia
2.
J Mater Chem B ; 9(31): 6155-6162, 2021 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-34318782

RESUMO

The limited depth of the near infrared (NIR) response is one of the major flaws of the present photothermal therapy (PTT). In this article, thermosensitive polyurethane urea (TPUU) was synthesized by polymerization. Subsequent experiments showed that, compared with classical photosensitizers, TPUU has higher photothermal effects and lower cytotoxicity. These valuable properties could make the present PTT research provide more therapeutic options among different tissues and organs. As a practical example, TPUU was applied to regulate the intestinal flora through external NIR irradiation, which implied its promising expanded applications in deeper tissues.


Assuntos
Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Fármacos Fotossensibilizantes/farmacologia , Terapia Fototérmica , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Raios Infravermelhos , Masculino , Neoplasias Mamárias Experimentais/tratamento farmacológico , Neoplasias Mamárias Experimentais/metabolismo , Neoplasias Mamárias Experimentais/patologia , Teste de Materiais , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Polimerização , Poliuretanos/química , Poliuretanos/farmacologia , Células Tumorais Cultivadas , Ureia/análogos & derivados , Ureia/química , Ureia/farmacologia
3.
Mater Sci Eng C Mater Biol Appl ; 124: 112066, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33947559

RESUMO

The healing process of open wounds is a competition between cells and bacteria. Therefore, a strategy that can quickly remove bacteria and promote cell proliferation to accelerate wound healing is urgently needed. Inspired by photoelectric synergy tactics, we improved both the optical and electrical response of zinc oxide (ZnO) through the modification of polydopamine (PDA) and reduced graphene oxide (rGO), thus obtaining a ZnO composite named PDA-rGO-ZnO (PrZ). Combined with the photoelectric double stimulation, the sterilization target could be completed from multiple physical levels simultaneously. More importantly, the band gap of ZnO was considerably narrowed by PDA encapsulation. The encapsulated ZnO thus could be effectively excited by pure yellow light (YL) with a moderate long wavelength, which fundamentally improved its safety in exerting photocatalytic antibacterial properties. In addition, we found that electrical stimulation (ES) could not only help to clear bacteria, but also facilitate the formation of new blood vessels. Animal experiments further showed that PrZ efficaciously regulated the immune response around the wound surface, promoted cell proliferation and the formation of collagen fibers, thereby accelerating wound healing.


Assuntos
Traumatismo Múltiplo , Nanocompostos , Óxido de Zinco , Animais , Luz , Cicatrização
4.
Adv Healthc Mater ; 10(13): e2100259, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33871179

RESUMO

Compared with traditional glasses, the comfortable and convenient contact lens (CL) has seen an upsurge among the public. However, due to the lack of antibacterial properties of ordinary CLs, the risk of eye infection is greatly increased accordingly. On the other hand, ordinary CLs also cannot effectively reduce the short-wavelength blue light emitted from electronic products, such as mobile phones and computers. Aiming at the above two problems, zinc oxide (ZnO)/cyclized polyacrylonitrile (CPAN) composites are developed for CL modification. After loading with ZnO/CPAN (ZC), the CL shows a broad-spectrum antibacterial property. Further experiments also prove that it can block UVB, UVA, as well as blue light selectively, under the premise of ensuring hydrophilicity and certain transparency. Theoretically, this ZC-decorated CL can fundamentally reduce the damage to the eyes from harmful light emitted by light-emitting diodes and the secretion of pro-inflammatory factors, which is thus a promising eye protection strategy for modern society.


Assuntos
Lentes de Contato , Óxido de Zinco , Resinas Acrílicas , Antibacterianos/farmacologia , Luz , Óxido de Zinco/farmacologia
5.
Adv Healthc Mater ; 10(8): e2001966, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33496389

RESUMO

A new monoglyceride-based heat-sensitive substrate is proposed, for the first time, as a wound management system. First, an appropriate portion of glyceryl monooleate (GMO) and glyceryl monostearate (GMS) is mixed to provide a thermal phase responsive matrix (GMO-GMS, GG). Subsequently, to improve the photothermal responsive and antibacterial performance, silver nanoparticles (Ag) decorated reduced graphene oxide (rGO) nanocomposite (rGO-Ag) is added to the GG matrix to obtain (GG-rGO-Ag). According to the systematic studies from uninfected, infected, and diabetic wound models, by applying near infrared (NIR) laser, the phase change of GG-rGO-Ag can be triggered to release Ag on demand for sterilization. More importantly, this smart GG substrate can also promote the production of vascular endothelial growth factor protein, thus serving as a NIR defined mufti-effective wound management system.


Assuntos
Grafite , Nanopartículas Metálicas , Nanocompostos , Monoglicerídeos , Prata , Fator A de Crescimento do Endotélio Vascular
6.
Sci Total Environ ; 565: 539-546, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27196991

RESUMO

Land reclamation has been highly intensive in China, resulting in a large amount of soil organic carbon (SOC) loss to the atmosphere. Evaluating the factors which drive SOC dynamics and carbon sequestration potential in reclaimed land is critical for improving soil fertility and mitigating global warming. This study aims to determine the current status and factors important to the SOC density in a typical reclaimed land located in Eastern China, where land reclamation has been undergoing for centuries. A total of 4746 topsoil samples were collected from 2007 to 2010. The SOC density of the reclaimed land (3.18±0.05kgCm(-2); mean±standard error) is significantly lower than that of the adjacent non-reclaimed land (5.71±0.04kgCm(-2)) (p<0.05). A Random Forest model is developed and it captures the relationships between the SOC density and the environmental/anthropogenic factors (R(2)=0.59). The soil pH, land use, and elevation are the most important factors for determining SOC dynamics. In contrast, the effect of the reclamation age on the SOC density is negligible, where SOC content in the land reclaimed during years 1047-1724 is as low as that reclaimed during years 1945-2004. The scenario analysis results indicate that the carbon sequestration potential of the reclaimed lands may achieve a maximum of 5.80±1.81kgCO2m(-2) (mean±SD) when dryland is converted to flooded land with vegetable-rice cropping system and soil pH of ~5.9. Note that in some scenarios the methane emission substantially offsets the carbon sequestration potential, especially for continuous rice cropping system. With the optimal setting for carbon sequestration, it is estimated that the dryland reclaimed in the last 50years in China is able to sequester 0.12milliontons CO2 equivalent per year.

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