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1.
ACS Appl Mater Interfaces ; 14(9): 11177-11191, 2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35192338

RESUMO

Silk sutures with antibacterial and anti-inflammatory functions were developed for sustained dual-drug delivery to prevent surgical site infections (SSIs). The silk sutures were prepared with core-shell structures braided from degummed silk filaments and then coated with a silk fibroin (SF) layer loaded with berberine (BB) and artemisinin (ART). Both the rapid release of drugs to prevent initial biofilm formation and the following sustained release to maintain effective concentrations for more than 42 days were demonstrated. In vitro assays using human fibroblasts (Hs 865.Sk) demonstrated cell proliferation on the materials, and hemolysis was 2.4 ± 0.8%, lower than that required by ISO 10993-4 standard. The sutures inhibited platelet adhesion and promoted collagen deposition and blood vessel formation. In vivo assessments using Sprague-Dawley (SD) rats indicated that the coating reduced the expression of pro-inflammatory cytokines interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α), shortening the inflammatory period and promoting angiogenesis. The results demonstrated that these new sutures exhibited stable structures, favorable biocompatibility, and sustainable antibacterial and anti-inflammatory functions with potential for surgical applications.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Seda/química , Seda/farmacologia , Infecção da Ferida Cirúrgica/prevenção & controle , Suturas , Animais , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Artemisininas/química , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Berberina/química , Berberina/farmacologia , Berberina/uso terapêutico , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Quimioterapia Combinada/métodos , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Humanos , Masculino , Fenômenos Físicos , Ratos Sprague-Dawley , Seda/uso terapêutico , Staphylococcus aureus/efeitos dos fármacos , Infecção da Ferida Cirúrgica/metabolismo , Infecção da Ferida Cirúrgica/patologia
2.
ACS Appl Mater Interfaces ; 13(41): 48403-48413, 2021 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-34610742

RESUMO

Biofilms formed from the pathogenic bacteria that attach to the surfaces of biomedical devices and implantable materials result in various persistent and chronic bacterial infections, posing serious threats to human health. Compared to the elimination of matured biofilms, prevention of the formation of biofilms is expected to be a more effective way for the treatment of biofilm-associated infections. Herein, we develop a facile method for endowing diverse substrates with long-term antibiofilm property by deposition of a hybrid film composed of tannic acid/Cu ion (TA/Cu) complex and poly(ethylene glycol) (PEG). In this system, the TA/Cu complex acts as a multifunctional building block with three different roles: (i) as a versatile "glue" with universal adherent property for substrate modification, (ii) as a photothermal biocidal agent for bacterial elimination under irradiation of near-infrared (NIR) laser, and (iii) as a potent linker for immobilization of PEG with inherent antifouling property to inhibit adhesion and accumulation of bacteria. The resulted hybrid film shows negligible cytotoxicity and good histocompatibility and could prevent biofilm formation for at least 15 days in vitro and suppress bacterial infection in vivo, showing great potential for practical applications to solve the biofilm-associated problems of biomedical materials and devices.


Assuntos
Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Incrustação Biológica/prevenção & controle , Materiais Revestidos Biocompatíveis/uso terapêutico , Cobre/uso terapêutico , Taninos/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/efeitos da radiação , Antibacterianos/toxicidade , Aderência Bacteriana/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/efeitos da radiação , Materiais Revestidos Biocompatíveis/toxicidade , Cobre/química , Cobre/efeitos da radiação , Cobre/toxicidade , Escherichia coli/efeitos dos fármacos , Raios Infravermelhos , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Terapia Fototérmica , Polietilenoglicóis/química , Polietilenoglicóis/toxicidade , Ratos Sprague-Dawley , Pele/patologia , Infecções Cutâneas Estafilocócicas/tratamento farmacológico , Infecções Cutâneas Estafilocócicas/patologia , Staphylococcus aureus/efeitos dos fármacos , Taninos/química , Taninos/efeitos da radiação , Taninos/toxicidade
3.
ACS Appl Mater Interfaces ; 12(50): 55638-55648, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33270424

RESUMO

Preventing bacterial colonization on scaffolds while supporting tissue formation is highly desirable in tissue engineering as bacterial infection remains a clinically significant risk to any implanted biomaterials. Elemental selenium (Se0) nanoparticles have emerged as a promising antimicrobial biomaterial without tissue cell toxicity, yet it remains unknown if their biological properties are from soluble Se ions or from direct cell-nanoparticle interactions. To answer this question, in this study, we developed a layered coating consisting of a Se nanoparticle layer underneath a micrometer-thick, biomimetic calcium phosphate (CaP) layer. We showed, for the first time, that the release of soluble HSe- ions from the Se nanoparticles strongly inhibited planktonic growth and biofilm formation of key bacteria, Staphylococcus aureus. The Se-CaP coating was found to support higher bone formation than the CaP-only coating in critical-size calvarial defects in rats; this finding could be directly attributed to the released soluble Se ions as the CaP layers in both groups had no detectable differences in the porous morphology, chemistry, and release of Ca or P. The Se-CaP coating was highly versatile and applicable to various surface chemistries as it formed through simple precipitation from aqueous solutions at room temperature and therefore could be promising in bone regeneration scaffolds or orthopedic implant applications.


Assuntos
Anti-Infecciosos/química , Fosfatos de Cálcio/química , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Selênio/química , Animais , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Doenças Ósseas/tratamento farmacológico , Doenças Ósseas/patologia , Regeneração Óssea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Poliésteres/química , Impressão Tridimensional , Ratos , Ratos Sprague-Dawley , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
4.
J Mater Chem B ; 8(26): 5765-5775, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32519722

RESUMO

Atherosclerosis can lead to thrombosis, blood supply disorders, and even serious consequences such as lumen occlusion or wall rupture and bleeding, so it is urgent to develop an effective comprehensive therapy. Here, a novel kind of drug-coated balloon, where drug-loaded porous nanomotors with autonomous motion ability are used as the coating of the balloon, is reported. The drug-loaded porous nanomotors based on Janus aminated mesoporous silica (JAMS) that was obtained by asymmetric modification of platinum (Pt) nanoparticles are prepared and characterized. The platelet membrane is used to wrap the nanomotors to reduce the leakage of drugs before reaching the plaque. The motion ability of the nanomotor under the irradiation of near-infrared light, the sustained release behavior and effect of the loaded drugs (anti-proliferative drug paclitaxel and the anti-vascular cell adhesion molecule-1 antibody) are investigated in detail. The biomimetic effect and encapsulation effect on drug loading of the platelet membrane, and the elimination of inflammatory macrophages under the photothermal effect produced by Pt are also characterized. The results indicate that the drug-loaded porous nanomotors proposed for drug balloon coating in this work can penetrate into the plaque and enhance the drug retention efficiency, realizing short-term photothermal elimination of inflammatory macrophages and long-term anti-proliferation effect of the drug, providing a possible choice for drug balloon coating with high efficiency in the treatment of atherosclerosis.


Assuntos
Anticorpos/uso terapêutico , Aterosclerose/tratamento farmacológico , Materiais Revestidos Biocompatíveis/uso terapêutico , Nanopartículas/química , Paclitaxel/uso terapêutico , Fototerapia , Animais , Anticorpos/química , Aterosclerose/induzido quimicamente , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Terapia Combinada , Dieta Hiperlipídica/efeitos adversos , Humanos , Camundongos , Paclitaxel/química , Tamanho da Partícula , Platina/química , Porosidade , Células RAW 264.7 , Coelhos , Dióxido de Silício/química , Propriedades de Superfície
5.
Acta Biomater ; 107: 313-324, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32126308

RESUMO

Titanium-based endosseous implants with high antibacterial and osseointegration activities are extremely required in clinics. To achieve this line, herein the doped coatings with three kinds of Zn doses were micro-arc oxidized (MAOed) on Ti. They were examined to reveal a bilayered structure, in which the outer layer consisted completely of the amorphism comprising elements of Ti, O and Zn with Zn doped in the form of weaken Zn-O bonds, and the underlying layer was partially crystallized with nanocrystalline TiO2 and Zn2TiO4 to embed an amorphous matrix. While the Zn doped doses of the surface amorphous layers increased with elevating the MAOed voltages, the weaken Zn-O bonds in the amorphism were identified to act as both the contributor of Zn2+ controllable release and the generator of reactive oxide species (ROS) on the coatings. The enhanced HO• and O2-• formation on the elevated voltage MAOed coatings caused serious break of the cell walls and plasma membranes of S. aureus. In parallel, the enhanced Zn2+ release and extracellular H2O2 formation led to the enhanced intracellular ROS level of S. aureus, further aggravating the damage of plasma membrane, resulting in bacteria death. On contrary to the overdose of Zn doped coating, the moderate doses of Zn doped coatings did not induce additional intracellular ROS and attenuate viability and proliferation of osteoblasts in vitro, and promoted osseointegration in both S. aureus-uninfected and infected rat tibias, which ascribed to the strong antibacterial activity and un-attenuated cell function of the coatings in the infected case. STATEMENT OF SIGNIFICANCE: (1) The Zn-doped coatings revealed a bilayered structure of the surface layer comprising the Ti, O and Zn constructed amorphism with Zn in the form of weaken Zn-O bonds, and the underlying layer comprising nanocrystalline TiO2 and Zn2TiO4 to embed amorphous matrix. (2) The weaken Zn-O bonds in the amorphism were identified to act as both the contributor of Zn2+ controllable release and the generator of ROS on the coatings. (3) The enhanced Zn2+ release and ROS formation on the coatings killed S. aureus by inducing serious break of their cell walls and plasma membranes. This effect in combination of un-attenuated osteoblast proliferation endowed the moderate Zn doped coatings with enhanced osseointegration in S. aureus-infected rat tibias.


Assuntos
Antibacterianos/uso terapêutico , Materiais Revestidos Biocompatíveis/uso terapêutico , Osseointegração/efeitos dos fármacos , Tíbia/microbiologia , Titânio/uso terapêutico , Zinco/uso terapêutico , Animais , Antibacterianos/química , Antibacterianos/toxicidade , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/toxicidade , Escherichia coli/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Osteoblastos/efeitos dos fármacos , Células RAW 264.7 , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Titânio/química , Titânio/toxicidade , Zinco/química , Zinco/toxicidade
6.
Biomater Sci ; 8(1): 391-404, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31728464

RESUMO

Prevention of bacterial infection and promotion of osseointegration are two important issues for titanium (Ti) implants in medical research. In addition, after a biofilm is formed on the surface of implants, the immune system and antibiotic therapy may fail. In this work, bio-functionalized titanium dioxide (TiO2)/molybdenum disulfide (MoS2)/polydopamine (PDA)/arginine-glycine-aspartic acid (RGD) nanorod arrays (NAs) are prepared on Ti implants to not only kill bacteria noninvasively upon co-irradiation of 660 nm visible light (VL) and 808 nm near infrared (NIR) light, but also promote the osteogenic activity simultaneously. Dual light irradiation triggers the TiO2/MoS2 NA to generate hyperthermia and reactive oxygen species (ROS) in 10 min. The synergistic effects of the generated hyperthermia and ROS increase the bacterial membrane permeability and bacteria are killed rapidly and efficiently in vitro and in vivo. The biofilm is also eradicated and RGD on the nanorods improves cell adhesion, proliferation, and osteogenic differentiation. The strategy described here for the design of bio-functionalized coatings on Ti implants has great clinical potential in orthopedics, dentistry, and other medical fields.


Assuntos
Antibacterianos/química , Materiais Revestidos Biocompatíveis/química , Luz , Nanotubos/química , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Dissulfetos/química , Glutationa/química , Hipertermia Induzida , Indóis/química , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Molibdênio/química , Oligopeptídeos/química , Osteogênese/efeitos dos fármacos , Polímeros/química , Espécies Reativas de Oxigênio/metabolismo , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/patologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/patogenicidade , Titânio/química
7.
Mater Sci Eng C Mater Biol Appl ; 107: 110314, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761184

RESUMO

This review focuses on the biomedical applications and toxicity of spinel ferrite nanoparticles (SFNPs) with more emphasis on the recently published work. A critical review is provided on recent advances of SFNPs applications in biomedical areas. The novelty of SFNPs in addressing the bottleneck problems encountered in the areas of health; in particular, for diagnosis and treatment of tumour cells are well reviewed. Furthermore, research gaps, toxicity of SFNPs and areas which still need more attention are highlighted. Based on the result of this review, the SFNPs have unlimited capacity in cancer treatment, disease diagnosis, magnetic resonance imaging, drug delivery and release. Overall, stepping out of the conventional way of treatment is difficult but also essential in bringing long lasting solution for cancer and other diseases treatment. In fact, the toxicity study and commercialisation of the SFNPs based cancer treatment options are the main challenges and need further study, in order to reduce unforeseen consequences.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Hipertermia Induzida/métodos , Nanocompostos/química , Nanocompostos/uso terapêutico , Nanopartículas/química , Nanopartículas/uso terapêutico , Óxido de Alumínio/química , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Compostos Férricos/química , Humanos , Óxido de Magnésio/química , Nanocompostos/toxicidade , Nanopartículas/toxicidade , Neoplasias/diagnóstico
8.
IET Nanobiotechnol ; 13(8): 800-807, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31625519

RESUMO

Widespread resistance to antibiotics amongst pathogens has become a tremendous challenge of high morbidity and mortality rates which increases the needs to exploring novel methods of treatment. An efficient antimicrobial procedure to root out pathogenic bacteria is photothermal therapy. In this study, antimicrobial effects of a polypyrrole-carbon nanocomposite (PPy-C) upon laser irradiation in order to destroy the pathogenic gram-positive bacterium, methicillin-resistant Staphylococcus aureus (MRSA) were assessed. The bacterial cells were incubated with 500, 750 and 1000 µg ml-1 concentrations of PPy-C and irradiated with an 808-nm laser at a power density of 1.0 W cm-2. To indicate the biocompatibility and toxic effect of the nanocomposite without and with laser irradiation, the authors counted the number of CFUs and compared it to an untreated sample. Antibacterial mechanisms of PPy-C were assessed through temperature increment, reactive oxygen species production, and protein and DNA leakages. Photothermal heating assay showed that 26°C temperature increases in the presence of 1000 µg ml-1 PPy-C led to >98% killing of MRSA. Furthermore, 20 min radiation of near-infrared light to PPy-C in different concentrations indicated destruction and reduction in the MRSA biofilm formation. Therefore, PPy-C was introduced as a photothermal absorber with a bactericidal effect in MRSA.


Assuntos
Biofilmes , Carbono/química , Temperatura Alta/uso terapêutico , Staphylococcus aureus Resistente à Meticilina , Nanocompostos/uso terapêutico , Fototerapia/métodos , Polímeros/química , Pirróis/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Biofilmes/efeitos da radiação , Carbono/farmacologia , Carbono/uso terapêutico , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Humanos , Teste de Materiais , Resistência a Meticilina/efeitos dos fármacos , Resistência a Meticilina/efeitos da radiação , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/fisiologia , Staphylococcus aureus Resistente à Meticilina/efeitos da radiação , Testes de Sensibilidade Microbiana , Viabilidade Microbiana/efeitos da radiação , Nanocompostos/química , Polímeros/farmacologia , Polímeros/uso terapêutico , Pirróis/farmacologia , Pirróis/uso terapêutico , Infecções Estafilocócicas/terapia
9.
IET Nanobiotechnol ; 13(8): 842-849, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31625525

RESUMO

Gold nanorods (GNRs) with exceptional photothermal properties have held promising potential for application in the biomedical field. In this study, the authors achieved photothermal ablation by polyethylene glycol (PEG)-functionalised GNRs. Well-dispersed and uniform GNRs were produced through a seed-mediated growth method. A thermal camera was used to scrutinise the temperature distribution and efficiency of the photothermal properties of the GNRs, which were irradiated by an 808 nm laser on a silicon chip. They observed that the GNRs provided about a 5°C temperature increase and produced hyperthermia efficiently. Since GNRs need to be surface tailored with a biocompatible material rather than cetyltrimethylammonium bromide (CTAB), they chose methoxyl PEG thiol to modify the GNRs. By taking advantage of the alkaline environment that assists this functionalisation, they accomplished about 89% removal of CTAB and identified a PEG layer on the surface of the GNRs. The GNR biocompatibility was considerably improved without any shift of the optical properties. Hepatocellular carcinoma cells were incubated with GNRs for 24 h and then were irradiated with a near-infrared laser for 3 min. Few cells remained alive, which demonstrated the photothermal ablation ability of the GNRs.


Assuntos
Carcinoma Hepatocelular/terapia , Ouro/química , Neoplasias Hepáticas/terapia , Nanopartículas Metálicas/uso terapêutico , Fototerapia/métodos , Polietilenoglicóis/química , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Temperatura Alta , Humanos , Neoplasias Hepáticas/patologia , Teste de Materiais , Nanopartículas Metálicas/química , Nanotubos/química
10.
Nanomedicine (Lond) ; 14(17): 2355-2371, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31414606

RESUMO

Aim: Present work was undertaken to fabricate iron oxide nanoparticles (IONPs) using a green approach for increased therapeutic efficacy. Materials & methods: Two types of IONPs were synthesized, one without any coating (IONPUC) and other coated with Phyllanthus emblica (Amla) fruit extract (IONPA). Both the IONPs were characterized using different techniques and therapeutic efficacy was evaluated in A549 human lung cancer cell line. Results: IONPA were smaller in size with better dispersibility compared with IONPUC. They induced increased reactive oxygen species production, higher DNA damage and apoptosis, which resulted in increased toxicity to cancer cells in comparison to IONPUC. Conclusion: Higher uptake of IONPA and active components coating the surface, may be responsible for the increased therapeutic efficacy in cancer cells.


Assuntos
Compostos Férricos/uso terapêutico , Neoplasias Pulmonares/terapia , Nanopartículas/uso terapêutico , Phyllanthus emblica/química , Extratos Vegetais/uso terapêutico , Células A549 , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Compostos Férricos/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Nanomedicina , Nanopartículas/química , Extratos Vegetais/química , Espécies Reativas de Oxigênio/metabolismo
11.
ACS Appl Mater Interfaces ; 11(30): 27269-27278, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31260238

RESUMO

Through a nature-inspired layer-by-layer assembly process, we developed a unique multifunctional tissue scaffold that consists of porous polyurethane substrate and nanoscale chitosan/graphene oxide hybrid coating. Alternative layers of drug-laden chitosan and graphene oxide nanosheets were held together through strong electrostatic interaction, giving rise to a robust multilayer architecture with control over structural element orientation and chemical composition at nanoscale. Combined pH-controlled co-delivery of multiple therapeutic agents and photothermal therapy has been achieved by our scaffold system. The new platform technology can be generalized to produce other tissue scaffold systems and may enable potential multimodal therapeutic applications such as bone cancer managements.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Engenharia Tecidual , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/uso terapêutico , Liberação Controlada de Fármacos/efeitos dos fármacos , Durapatita/química , Grafite/química , Humanos , Concentração de Íons de Hidrogênio , Fototerapia , Porosidade , Alicerces Teciduais/química
12.
Biomaterials ; 207: 10-22, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30947118

RESUMO

Co-immobilization of two or more molecules with different and complementary functions to prevent thrombosis, suppress smooth muscle cell (SMC) proliferation, and support endothelial cell (EC) growth is generally considered to be promising for the re-endothelialization on cardiovascular stents. However, integration of molecules with distinct therapeutic effects does not necessarily result in synergistic physiological functions due to the lack of interactions among them, limiting their practical efficacy. Herein, we apply heparin and nitric oxide (NO), two key molecules of the physiological functions of endothelium, to develop an endothelium-mimetic coating. Such coating is achieved by sequential conjugation of heparin and the NO-generating compound selenocystamine (SeCA) on an amine-bearing film of plasma polymerized allylamine. The resulting surface combines the anti-coagulant (anti-FXa) function provided by the heparin and the anti-platelet activity of the catalytically produced NO. It also endows the stents with the ability to simultaneously up-regulate α-smooth muscle actin (α-SMA) expression and to increase cyclic guanylate monophosphate (cGMP) synthesis of SMC, thereby significantly promoting their contractile phenotype and suppressing their proliferation. Importantly, this endothelium-biomimetic coating creates a favorable microenvironment for EC over SMC. These features impressively improve the antithrombogenicity, re-endothelialization and anti-restenosis of vascular stents in vivo.


Assuntos
Bioengenharia/métodos , Biomimética/métodos , Materiais Revestidos Biocompatíveis/química , Stents Farmacológicos , Heparina/química , Óxido Nítrico/química , Actinas/metabolismo , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/uso terapêutico , Cistamina/análogos & derivados , Cistamina/química , Células Endoteliais da Veia Umbilical Humana , Humanos , Compostos Organosselênicos/química , Coelhos
13.
Sci Rep ; 9(1): 6198, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30996286

RESUMO

Microbial infections due to biofilms on medical implants can be prevented by antimicrobial coatings on biomaterial surfaces. Mesoporous silica nanoparticles (MSNPs) were synthesized via base-catalyzed sol-gel process at room temperature, functionalized with phenazine-1-carboxamide (PCN) and characterized by UV-visible, FT-IR, DLS, XRD spectroscopic techniques, SEM, TEM, TGA and BET analysis. Native MSNPs, PCN and PCN-MSNPs were evaluated for anti-Candida minimum inhibitory concentration (MIC), minimum fungicidal concentration (MFC), Candida albicans (C. albicans) biofilms and C. albicans-Staphylococcus aureus (S. aureus) polymicrobial biofilm inhibition. PCN-MSNPs were four-fold effective (MIC 3.9 µg mL-1; 17.47 µM) and MFC (7.8 µg mL-1; 34.94 µM) as compared to pure PCN (MIC 15.6 µg mL-1; 69.88 µM) and MFC (31.2 µg mL-1; 139.76 µM). PCN-MSNPs inhibited in vitro C. albicans MTCC 227-S. aureus MTCC 96 biofilms at very low concentration (10 µg mL-1; 44.79 µM) as compared to pure PCN (40 µg mL-1; 179.18 µM). Mechanistic studies revealed that PCN induced intracellular ROS accumulation in C. albicans MTCC 227, S. aureus MTCC 96 and S. aureus MLS-16 MTCC 2940, reduction in total ergosterol content, membrane permeability, disruption of ionic homeostasis followed by Na+, K+ and Ca2+ leakage leading to cell death in C. albicans MTCC 227 as confirmed by confocal laser scanning micrographs. The silicone urethral catheters coated with PCN-MSNPs (500 µg mL-1; 2.23 mM) exhibited no formation of C. albicans MTCC 227 - S. aureus MTCC 96 and C. albicans MTCC 227 - S. aureus MLS -16 MTCC 2940 biofilms. This is the first report on PCN-MSNPs for use as antimicrobial coatings against microbial adhesion and biofilm formation on silicone urethral catheters.


Assuntos
Anti-Infecciosos/uso terapêutico , Materiais Revestidos Biocompatíveis/química , Controle de Infecções/métodos , Nanopartículas/química , Cateteres Urinários , Biofilmes/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/uso terapêutico , Testes de Sensibilidade Microbiana , Nanopartículas/uso terapêutico , Fenazinas/química , Dióxido de Silício/química , Silicones , Staphylococcus aureus/efeitos dos fármacos , Cateteres Urinários/microbiologia
14.
ACS Appl Mater Interfaces ; 11(10): 10244-10253, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30689341

RESUMO

Excessive fibrosis is the topmost factor for the defeat of surgical glaucoma drainage device (GDD) implantation. Adjuvant drug approaches are promising to help reduce the scar formation and excessive fibrosis. Opal shale (OS), as a natural state and noncrystalline silica substance with poriferous nature and strong adsorbability, is highly likely to undertake drug loading and delivery. Here, we employed OS microparticles (MPs) by ultrasound and centrifugation and presented an innovative and improved GDD coated with OS MPs, which were loaded with mitomycin C (MMC). MMC-loaded OS MPs were physically absorbed on the Ahmed glaucoma valve surface through OS' adsorbability. About 5.51 µg of MMC was loaded on the modified Ahmed glaucoma valve and can be released for 18 days in vitro. MMC-loaded OS MPs inhibited fibroblast proliferation and showed low toxicity to primary Tenon's fibroblasts. The ameliorated drainage device was well tolerated and effective in reducing the fibrous reaction in vivo. Hence, our study constructed an improved Ahmed glaucoma valve using OS MPs without disturbing aqueous humor drainage pattern over the valve surface. The modified Ahmed glaucoma valve successfully alleviated scar tissue formation after GDD implantation surgery.


Assuntos
Materiais Revestidos Biocompatíveis/química , Fibrose/prevenção & controle , Implantes para Drenagem de Glaucoma , Glaucoma/tratamento farmacológico , Adsorção/efeitos dos fármacos , Micropartículas Derivadas de Células/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Liberação Controlada de Fármacos , Fibrose/patologia , Glaucoma/patologia , Glaucoma/cirurgia , Humanos , Mitomicina/química , Mitomicina/uso terapêutico , Dióxido de Silício/química
15.
J Nanobiotechnology ; 15(1): 74, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-29041937

RESUMO

BACKGROUND: Biologics magnetics nanoparticles, magnetosomes, attract attention because of their magnetic characteristics and potential applications. The aim of the present study was to develop and characterize novel magnetosomes, which were extracted from magnetotactic bacteria, purified to produce apyrogen magnetosome minerals, and then coated with Chitosan, Neridronate, or Polyethyleneimine. It yielded stable magnetosomes designated as M-Chi, M-Neri, and M-PEI, respectively. Nanoparticle biocompatibility was evaluated on mouse fibroblast cells (3T3), mouse glioblastoma cells (GL-261) and rat glioblastoma cells (RG-2). We also tested these nanoparticles for magnetic hyperthermia treatment of tumor in vitro on two tumor cell lines GL-261 and RG-2 under the application of an alternating magnetic field. Heating, efficacy and internalization properties were then evaluated. RESULTS: Nanoparticles coated with chitosan, polyethyleneimine and neridronate are apyrogen, biocompatible and stable in aqueous suspension. The presence of a thin coating in M-Chi and M-PEI favors an arrangement in chains of the magnetosomes, similar to that observed in magnetosomes directly extracted from magnetotactic bacteria, while the thick matrix embedding M-Neri leads to structures with an average thickness of 3.5 µm2 per magnetosome mineral. In the presence of GL-261 cells and upon the application of an alternating magnetic field, M-PEI and M-Chi lead to the highest specific absorption rates of 120-125 W/gFe. Furthermore, while M-Chi lead to rather low rates of cellular internalization, M-PEI strongly associate to cells, a property modulated by the application of an alternating magnetic field. CONCLUSIONS: Coating of purified magnetosome minerals can therefore be chosen to control the interactions of nanoparticles with cells, organization of the minerals, as well as heating and cytotoxicity properties, which are important parameters to be considered in the design of a magnetic hyperthermia treatment of tumor.


Assuntos
Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Glioma/terapia , Magnetossomos/química , Nanopartículas/química , Nanopartículas/uso terapêutico , Células 3T3 , Animais , Linhagem Celular Tumoral , Quitosana/química , Quitosana/uso terapêutico , Difosfonatos/química , Difosfonatos/uso terapêutico , Hipertermia Induzida , Campos Magnéticos , Magnetospirillum/química , Camundongos , Polietilenoimina/química , Polietilenoimina/uso terapêutico , Ratos
16.
Biomaterials ; 143: 130-141, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28800434

RESUMO

In this study, we reported a strategy to improve delivery efficiency of a long-circulation biomimetic photothermal nanoagent for enhanced photothermal therapy through selectively dilating tumor vasculature. By using a simply nanocoating technology, a biomimetic layer of natural red blood cell (RBC) membranes was camouflaged on the surface of photothermal polypyrrole nanoparticles (PPy@RBC NPs). The erythrocyte-mimicking PPy NPs inherited the immune evasion ability from natural RBC resulting in superior prolonged blood retention time. Additionally, excellent photothermal and photoacoustic imaging functionalities were all retained attributing to PPy NPs cores. To further improve the photothermal outcome, the endothelin A (ETA) receptor antagonist BQ123 was jointly employed to regulate tumor microenvironment. The BQ123 could induce tumor vascular relaxation and increase blood flow perfusion through modulating an ET-1/ETA transduction pathway and blocking the ETA receptor, whereas the vessel perfusion of normal tissues was not altered. Through our well-designed tactic, the concentration of biomimetic PPy NPs in tumor site was significantly improved when administered systematically. The study documented that the antitumor efficiency of biomimetic PPy NPs combined with specific antagonist BQ123 was particularly prominent and was superior to biomimetic PPy NPs (P < 0.05) and PEGylated PPy NPs with BQ123 (P < 0.01), showing that the greatly enhanced photothermal treatment could be achieved with low-dose administration of photothermal agents. Our findings would provide a promising procedure for other similar enhanced photothermal treatment by blocking ETA receptor to dramatically increase the delivery of biomimetic photothermal nanomaterials.


Assuntos
Antagonistas dos Receptores de Endotelina/uso terapêutico , Hipertermia Induzida/métodos , Nanopartículas/uso terapêutico , Neoplasias/terapia , Peptídeos Cíclicos/uso terapêutico , Fototerapia/métodos , Polímeros/uso terapêutico , Pirróis/uso terapêutico , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/uso terapêutico , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/uso terapêutico , Antagonistas dos Receptores de Endotelina/química , Membrana Eritrocítica/química , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Neoplasias/irrigação sanguínea , Peptídeos Cíclicos/química , Polímeros/química , Pirróis/química , Células RAW 264.7
17.
Biomaterials ; 143: 29-45, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28756194

RESUMO

Photothermal therapy (PTT) has represented a promising noninvasive approach for cancer treatment in recent years. However, there still remain challenges in developing non-toxic and biodegradable biomaterials with high photothermal efficiency in vivo. Herein, we explored natural melanin nanoparticles extracted from living cuttlefish as effective photothermal agents and developed red blood cell (RBC) membrane-camouflaged melanin (Melanin@RBC) nanoparticles as a platform for in vivo antitumor PTT. The as-obtained natural melanin nanoparticles demonstrated strong absorption at NIR region, higher photothermal conversion efficiency (∼40%) than synthesized melanin-like polydopamine nanoparticles (∼29%), as well as favorable biocompatibility and biodegradability. It was shown that RBC membrane coating on melanin nanoparticles retained their excellent photothermal property, enhanced their blood retention and effectively improved their accumulation at tumor sites. With the guidance of their inherited photoacoustic imaging capability, optimal accumulation of Melanin@RBC at tumors was achieved around 4 h post intravenous injection. Upon irradiation by an 808-nm laser, the developed Melanin@RBC nanoparticles exhibited significantly higher PTT efficacy than that of bare melanin nanoparticles in A549 tumor-bearing mice. Given that both melanin nanoparticles and RBC membrane are native biomaterials, the developed Melanin@RBC platform could have great potential in clinics for anticancer PTT.


Assuntos
Materiais Revestidos Biocompatíveis/uso terapêutico , Membrana Eritrocítica/química , Hipertermia Induzida/métodos , Melaninas/uso terapêutico , Nanopartículas/uso terapêutico , Neoplasias/terapia , Fototerapia/métodos , Células A549 , Animais , Materiais Revestidos Biocompatíveis/química , Decapodiformes/química , Humanos , Masculino , Melaninas/química , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Camundongos Nus , Nanopartículas/química , Nanopartículas/ultraestrutura , Neoplasias/patologia
18.
Biomaterials ; 141: 210-222, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28689117

RESUMO

Magnetic hyperthermia was reported to increase the survival of patients with recurrent glioblastoma by 7 months. This promising result may potentially be further improved by using iron oxide nanoparticles, called magnetosomes, which are synthesized by magnetotactic bacteria, extracted from these bacteria, purified to remove most endotoxins and organic material, and then coated with poly-l-lysine to yield a stable and non-pyrogenic nanoparticle suspension. Due to their ferrimagnetic behavior, high crystallinity and chain arrangement, these magnetosomes coated with poly-l-lysine (M-PLL) are characterized by a higher heating power than their chemically synthesized counterparts currently used in clinical trials. M-PLL-enhanced antitumor efficacy was demonstrated by administering 500-700 µg in iron of M-PLL to intracranial U87-Luc tumors of 1.5 mm3 and by exposing mice to 27 magnetic sessions each lasting 30 min, during which an alternating magnetic field of 202 kHz and 27 mT was applied. Treatment conditions were adjusted to reach a typical hyperthermia temperature of 42 °C during the first magnetic session. In 100% of treated mice, bioluminescence due to living glioblastoma cells fully disappeared 68 days following tumor cell implantation (D68). These mice were all still alive at D350. Histological analysis of their brain tissues revealed an absence of tumor cells, suggesting that they were fully cured. In comparison, antitumor efficacy was less pronounced in mice treated by the administration of IONP followed by 23 magnetic sessions, leading to full tumor bioluminescence disappearance in only 20% of the treated mice.


Assuntos
Neoplasias Encefálicas/terapia , Materiais Revestidos Biocompatíveis/uso terapêutico , Óxido Ferroso-Férrico/uso terapêutico , Glioblastoma/terapia , Hipertermia Induzida/métodos , Magnetossomos/química , Polilisina/uso terapêutico , Células 3T3 , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/química , Feminino , Óxido Ferroso-Férrico/química , Glioblastoma/patologia , Humanos , Campos Magnéticos , Magnetossomos/ultraestrutura , Magnetospirillum/química , Camundongos , Camundongos Nus , Polilisina/análogos & derivados
19.
Int J Low Extrem Wounds ; 15(3): 203-12, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27440796

RESUMO

Technological advancement has assisted in developing various availabilities of wound products that help in not only in healing and preventing infection but also in providing patients' comfort and pain reduction during application. However, most of advanced wound healing products in Thailand were imported at high costs to patients. Nowadays, there are increased numbers of local researches of herbs that could provide healing environment for successful wound care. Herbal wound products are currently being introduced as alternatives to those imported dressings. The aim of this study was to report the clinical efficacy of using polyester containing herbal extract dressings in healing of second-degree burns. The volunteers were divided by simply randomized method into the study group of patient using polyester containing herbal extract dressing and the control group of patients treating with dressings that are commercially available and common use. The standard treatment protocols were performed at every 3 days of dressing change. Comparative evaluation consisted of time of healing, length of hospital stays, pain analog score assessment, percentage of infection, and descriptive notification of unfavorable clinical symptoms or signs or side effects.


Assuntos
Aloe , Queimaduras , Centella , Manejo da Dor/métodos , Poliésteres , Infecção dos Ferimentos , Adulto , Bandagens , Queimaduras/complicações , Queimaduras/fisiopatologia , Materiais Revestidos Biocompatíveis/efeitos adversos , Materiais Revestidos Biocompatíveis/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Extratos Vegetais/efeitos adversos , Extratos Vegetais/uso terapêutico , Poliésteres/efeitos adversos , Poliésteres/uso terapêutico , Tailândia , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Infecção dos Ferimentos/etiologia , Infecção dos Ferimentos/prevenção & controle
20.
Rom J Morphol Embryol ; 57(1): 107-14, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27151695

RESUMO

This work presents a novel nano-modified coating for wound dressings and other medical devices with anti-infective properties, based on functionalized zinc oxide nanostructures and orange oil (ZnO@OO). The obtained nanosurfaces were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), selected area electron diffraction (SAED), differential thermal analysis-thermogravimetry (DTA-TG), X-ray diffraction (XRD), and Fourier transform infrared (FT-IR) spectroscopy. The obtained nanocomposite coatings exhibited an antimicrobial activity superior to bare ZnO nanoparticles (NPs) and to the control antibiotic against Staphylococcus aureus and Escherichia coli, as revealed by the lower minimal inhibitory concentration values. For the quantitative measurement of biofilm-embedded microbial cells, a culture-based, viable cell count method was used. The coated wound dressings proved to be more resistant to S. aureus microbial colonization and biofilm formation compared to the uncoated controls. These results, correlated with the good in vivo biodistribution open new directions for the design of nanostructured bioactive coating and surfaces, which can find applications in the medical field, for obtaining improved bioactive wound dressings and prosthetic devices, but also in food packaging and cosmetic industry.


Assuntos
Anti-Infecciosos/uso terapêutico , Bandagens , Materiais Revestidos Biocompatíveis/uso terapêutico , Óleos de Plantas/uso terapêutico , Ferimentos e Lesões/tratamento farmacológico , Óxido de Zinco/uso terapêutico , Animais , Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Óleos de Plantas/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Difração de Raios X , Óxido de Zinco/farmacologia
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