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1.
Macromol Rapid Commun ; 41(7): e2000013, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32068937

RESUMO

Thermadapt shape memory polymers (SMPs), utilizing a variety of dynamic covalent bond exchange mechanisms, have been extensively studied in recent years but it is still challenging to address several constraints in terms of limited accuracy and complexity for constructing 3D shape memory structures. Here, an effective and facile preparation of thermadapt SMPs based on elemental sulfur-derived poly(phenylene polysulfide) networks (PSNs) is presented. These SMPs possess intrinsic near-infrared (NIR)-induced photothermal conversion properties for spatiotemporal control of their plasticity and elasticity. The NIR-controllable plasticity and elasticity of the PSNs enable versatile shape manipulation of 3D multi-shape memory structures, including building block assembly, reconfiguration, shape fixing/recovery, and repair.


Assuntos
Materiais Biocompatíveis/química , Sulfetos/química , Enxofre/química , Elasticidade , Raios Infravermelhos , Teste de Materiais , Estrutura Molecular , Tamanho da Partícula
2.
Biomacromolecules ; 15(4): 1382-9, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24598017

RESUMO

Self-assembled polymeric nanocapsules (NCs) that incorporate dendrimer porphyrin (DP) in the shells and superparamagnetic iron oxide nanoparticles (SPIONs) in the cores are fabricated to create a theragnostic platform for the application in photodynamic therapy (PDT) and magnetic resonance imaging (MRI). SPIONs-embedded polystyrene NPs (SPIONs@PS) are used as a template to build up multilayered NCs. The formation of PAH/DP multilayer on the SPIONs@PS is monitored by zeta-pential and fluorescence emission measurement, because the porphyrin unit in the core of DP has strong red fluorescence emission. NCs have strong enough magnetic property (>20 emu/g) for MRI application with typical superparamagnetic behavior, where the linear correlation of R2 and Fe concentration at diluted conditions led to corresponding T2 relaxivity coefficient (r2) value of 93.5 mM(-1) s(-1). Cell viability study upon light irradiation reveals that NCs can successfully work in photosensitizer formulation for PDT.


Assuntos
Imageamento por Ressonância Magnética/métodos , Nanocápsulas/química , Nanotecnologia/métodos , Fotoquimioterapia/métodos , Dendrímeros/química , Compostos Férricos/química , Fluorescência , Células HeLa/efeitos dos fármacos , Humanos , Nanocápsulas/uso terapêutico , Nanocápsulas/toxicidade , Fármacos Fotossensibilizantes/química , Poliaminas/química , Poliestirenos/química , Porfirinas/química , Espécies Reativas de Oxigênio/análise
3.
Langmuir ; 29(20): 5962-7, 2013 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-23650947

RESUMO

This paper describes the preparation of magnetic nanoparticles modified with polyethylenimine (PEI)-folic acid (PF) conjugate and their potential biomedical applications. Magnetic nanoparticles modified with (3-(2-aminoethylamino)propyltrimethoxysilane) (AEAPS) were first prepared using a ligand exchange method to provide biocompatibility and hydrophilicity, and further conjugated with PF to carry gene and enhance specific uptake into cancer cells. We demonstrated the feasibility of the multifunctional magnetic nanoparticles as contrast agents in magnetic resonance imaging (MRI) and as gene carriers for gene delivery. In vitro results revealed that the cytotoxicity of the multifunctional magnetic nanoparticles was lower compared to that of pristine magnetic nanoparticles. Furthermore, we demonstrated the specific uptake of the magnetic nanoparticles modified with PF to KB cells using WI-38 cells as comparison by confocal microscopy. The PF-modified magnetic nanoparticles can potentially be employed as theranostic nanoplatforms for targeted gene delivery to cancer cells and simultaneous magnetic resonance imaging.


Assuntos
Ácido Fólico/química , Nanopartículas de Magnetita/química , Polietilenoimina/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ácido Fólico/farmacologia , Técnicas de Transferência de Genes , Humanos , Células KB , Imageamento por Ressonância Magnética , Tamanho da Partícula , Polietilenoimina/farmacologia , Relação Estrutura-Atividade , Propriedades de Superfície
4.
Sci Rep ; 6: 36078, 2016 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-27782212

RESUMO

As insufficient access to clean water is expected to become worse in the near future, water purification is becoming increasingly important. Membrane filtration is the most promising technologies to produce clean water from contaminated water. Although there have been many studies to prepare highly water-permeable carbon-based membranes by utilizing frictionless water flow inside the carbonaceous pores, the carbon-based membranes still suffer from several issues, such as high cost and complicated fabrication as well as relatively low salt rejection. Here, we report for the first time the use of microporous carbonaceous membranes via controlled carbonization of polymer membranes with uniform microporosity for high-flux nanofiltration. Further enhancement of membrane performance is observed by O2 plasma treatment. The optimized membrane exhibits high water flux (13.30 LMH Bar-1) and good MgSO4 rejection (77.38%) as well as antifouling properties. This study provides insight into the design of microporous carbonaceous membranes for water purification.


Assuntos
Carbono/química , Membranas Artificiais , Oxigênio/química , Gases em Plasma/química , Purificação da Água/instrumentação , Purificação da Água/métodos , Porosidade
5.
Korean J Intern Med ; 29(3): 370-4, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24851072

RESUMO

Various adverse events have been reported during combination therapy with pegylated (PEG)-interferon-α and ribavirin, although opportunistic infections, especially cryptococcal meningitis, are very rare. A 61-year-old woman complained of headaches and a fever during treatment of a chronic hepatitis C virus (HCV) infection. She had been treated for 7 months. Her headaches were refractory to analgesics, and she developed subtle nuchal rigidity. The cerebral spinal fluid (CSF) revealed a white blood cell count of 205/mm(3), 51 mg/dL protein, 35 mg/dL glucose, and negative Cryptococcus antigen. The CSF culture resulted in no growth. Five days later, the CSF was positive for Cryptococcus antigen. We administered amphotericin B and flucytosine, followed by fluconazole. Approximately 2 months later, she was discharged. For the first time, we report a case of cryptococcal meningitis during the treatment of chronic HCV with PEG-interferon-α and ribavirin.


Assuntos
Antivirais/efeitos adversos , Cryptococcus neoformans/patogenicidade , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/efeitos adversos , Meningite Criptocócica/microbiologia , Infecções Oportunistas/microbiologia , Polietilenoglicóis/efeitos adversos , Ribavirina/efeitos adversos , Antifúngicos/uso terapêutico , Cryptococcus neoformans/imunologia , Quimioterapia Combinada , Feminino , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/imunologia , Humanos , Hospedeiro Imunocomprometido , Interferon alfa-2 , Meningite Criptocócica/tratamento farmacológico , Meningite Criptocócica/imunologia , Pessoa de Meia-Idade , Infecções Oportunistas/diagnóstico , Infecções Oportunistas/tratamento farmacológico , Infecções Oportunistas/imunologia , Proteínas Recombinantes/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
6.
J Colloid Interface Sci ; 379(1): 27-32, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22613627

RESUMO

Multifunctional fluorescent and superparamagnetic Fe(3)O(4)/poly(fluorescein O-methacrylate) [Fe(3)O(4)/poly(FMA)] nanoparticles with core/shell structure were synthesized via surface-initiated polymerization. First, polymerizable double bonds were introduced onto the surface of Fe(3)O(4) nanoparticles via ligand exchange and a condensation reaction. A fluorescent monomer, FMA, was then polymerized to the double bonds at the surface via free-radical polymerization, leading to form a fluorescent polymer shell around the superparamagnetic Fe(3)O(4) core. The resultant Fe(3)O(4)/poly(FMA) nanoparticles were characterized by Fourier transform infrared, nuclear magnetic resonance, and X-ray diffraction spectroscopy to confirm the reactions. Transmission electron microscopy images showed that the Fe(3)O(4)/poly(FMA) nanoparticles have a spherical and monodisperse core/shell morphology. Photoluminescence spectroscopy and superconducting quantum interference device magnetometer analyses confirmed that the Fe(3)O(4)/poly(FMA) nanoparticles exhibited fluorescent and superparamagnetic properties, respectively. In addition, we demonstrated the potential bioimaging application of the Fe(3)O(4)/poly(FMA) nanoparticles by visualizing the cellular uptake of the nanoparticles into A549 lung cancer cells.


Assuntos
Resinas Acrílicas/química , Fluoresceínas/química , Nanopartículas de Magnetita/química , Linhagem Celular Tumoral , Humanos , Nanopartículas de Magnetita/ultraestrutura , Polimerização , Propriedades de Superfície
7.
Ann Dermatol ; 22(1): 88-90, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20548892

RESUMO

"Fiddler's neck" is an irritant contact dermatitis that frequently affects violin and viola players. The etiology of the skin changes associated with this condition are probably attributable to a combination of factors--including increased pressure, friction, poor hygiene, and excessive perspiration. Clinically, the lesions generally consist of a localized area of lichenification on the left side of the neck just below the angle of the jaw. Herein, we report a case of fiddler's neck in a viola player, attended by allergic contact dermatitis to the nickel in the metal fixtures of a viola. We hope that our case report draws the attention of dermatologists toward this, and many other skin problems that affect musicians.

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