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1.
Int J Nanomedicine ; 15: 7215-7234, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061377

RESUMO

Background: With excellent shape memory and superelastic properties, shape memory alloy (SMA) is an ideal actuator, and it can form smart structure for different applications in medical field. However, SMA devices cause apparent thermal damage to the surrounding tissues when it works in vivo, making the application of smart structure that is composed of SMA actuator in vivo is greatly limited. Methods: In this paper, coating (APA) with PLA as the main body to limit the heat conduction, a multifunctional Ag nanoparticles (AgNPs)/polylactic acid (PLA)/Al2O3 was synthesized. The Al2O3 layer was formed by micro-arc oxidation (MAO) and AgNPs were synthesized by silver nitrate and ethylene glycol. Scanning electron microscopy, transmission electron microscope, and Fourier transform infrared spectra were applied to analyze the morphology and characterization of APA coating. The antimicrobial activity, thermal insulation activity, and biocompatibility of APA coating were furtherly explored and verified through animal experiments and immunohistochemistry. Results: With different particle sizes and concentrations of AgNPs, APA multi-functional films were successfully prepared. The Al2O3 layer was closely combined with SMA and formed a porous surface, so the PLA and AgNPs layers can firmly adhere to SMA, thus reducing the release of nickel ions in SMA. AgNPs gave APA coating excellent antibacterial activity and effectively inhibited the growth of Staphylococcus aureus. In addition, coupled with the low thermal conductivity of PLA and Al2O3, AgNPs were tightly anchored on the surface of PLA, which has high infrared reflectivity, making the APA coating obtain good thermal insulation performance. Conclusion: We have successfully prepared the APA coating and obtained the optimum amount of AgNPs, which makes it have good thermal insulation performance, good antibacterial activity and good biocompatibility, which provides a new prospect for the application of SMA.


Assuntos
Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Níquel/farmacologia , Temperatura , Titânio/farmacologia , Óxido de Alumínio/farmacologia , Animais , Linhagem Celular , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Poliésteres/farmacologia , Coelhos , Prata/farmacologia , Staphylococcus aureus/efeitos dos fármacos
2.
Molecules ; 25(15)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731428

RESUMO

In 2020, the world is being ravaged by the coronavirus, SARS-CoV-2, which causes a severe respiratory disease, Covid-19. Hundreds of thousands of people have succumbed to the disease. Efforts at curing the disease are aimed at finding a vaccine and/or developing antiviral drugs. Despite these efforts, the WHO warned that the virus might never be eradicated. Countries around the world have instated non-pharmaceutical interventions such as social distancing and wearing of masks in public to curb the spreading of the disease. Antiviral polysaccharides provide the ideal opportunity to combat the pathogen via pharmacotherapeutic applications. However, a layer-by-layer nanocoating approach is also envisioned to coat surfaces to which humans are exposed that could harbor pathogenic coronaviruses. By coating masks, clothing, and work surfaces in wet markets among others, these antiviral polysaccharides can ensure passive prevention of the spreading of the virus. It poses a so-called "eradicate-in-place" measure against the virus. Antiviral polysaccharides also provide a green chemistry pathway to virus eradication since these molecules are primarily of biological origin and can be modified by minimal synthetic approaches. They are biocompatible as well as biodegradable. This surface passivation approach could provide a powerful measure against the spreading of coronaviruses.


Assuntos
Antivirais/uso terapêutico , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Polissacarídeos/uso terapêutico , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/metabolismo , Materiais Revestidos Biocompatíveis/farmacologia , Materiais Revestidos Biocompatíveis/uso terapêutico , Química Verde , Humanos , Nanopartículas , Nanotecnologia , Polissacarídeos/farmacologia
3.
Int J Nanomedicine ; 15: 4171-4189, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32606671

RESUMO

Background: Angiogenic and osteogenic activities are two major problems with biomedical titanium (Ti) and other orthopedic implants used to repair large bone defects. Purpose: The aim of this study is to prepare hydroxyapatite (HA) coatings on the surface of Ti by using electrochemical deposition (ED), and to evaluate the effects of nanotopography and silicon (Si) doping on the angiogenic and osteogenic activities of the coating in vitro. Materials and Methods: HA coating and Si-doped HA (HS) coatings with varying nanotopographies were fabricated using two ED modes, ie, the pulsive current (PC) and cyclic voltammetry (CV) methods. The coatings were characterized through scanning electron microscope (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectrometer (XPS), and atomic force microscopy (AFM), and their in vitro bioactivity and protein adsorption were assessed. Using MC3T3-E1 pre-osteoblasts and HUVECs as cell models, the osteogenic and angiogenic capabilities of the coatings were evaluated through in vitro cellular experiments. Results: By controlling Si content in ~0.8 wt.%, the coatings resulting from the PC mode (HA-PC and HS-PC) and CV mode (HA-CV and HS-CV) had nanosheet and nanorod topographies, respectively. At lower crystallinity, higher ionic dissolution, smaller contact angle, higher surface roughness, and more negative zeta potential, the HS and PC samples exhibited quicker apatite deposition and higher BSA adsorption capacity. The in vitro cell study showed that Si doping was more favorable for enhancing the viability of the MC3T3-E1 cells, but nanosheet coating increased the area for cell spreading. Of the four coatings, HS-PC with Si doping and nanosheet topography exhibited the best effect in terms of up-regulating the expressions of the osteogenic genes (ALP, Col-I, OSX, OPN and OCN) in the MC3T3-E1 cells. Moreover, all leach liquors of the surface-coated Ti disks promoted the growth of the HUVECs, and the HS samples played a more significant role in promoting cell migration and tube formation than the HA samples. Of the four leach liquors, only the two HS samples up-regulated NO content and expressions of the angiogenesis-related genes (VEGF, bFGF and eNOS) in the HUVECs, and the HS-PC yielded a better effect. Conclusion: The results show that Si doping while regulating the topography of the coating can help enhance the bone regeneration and vascularization of HA-coated Ti implants.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Nanopartículas/química , Osteogênese , Próteses e Implantes , Silício/química , Titânio/farmacologia , Adsorção , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Camundongos , Nanopartículas/ultraestrutura , Nanotubos/química , Neovascularização Fisiológica/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Soroalbumina Bovina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Difração de Raios X
4.
J Interv Cardiol ; 2020: 1956015, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32410915

RESUMO

Objectives: We evaluated the effect of the different carrier systems on early vascular response through histological analysis and scanning electron microscopy using a porcine model. Background: Although Synergy™ and Promus PREMIER™ share an identical stent material and drug elution (everolimus), they use different drug carrier systems: biodegradable abluminal coating polymer or durable conformal coating polymer, respectively. However, data regarding the impact of the different coating systems on vessel healing are currently limited. Methods: Twelve Synergy™ and Promus PREMIER™ were implanted in 12 swine. Histopathological analysis of the stented segments was performed on the 2nd and 14th days after implantation. Morphometric analysis of the inflammation and intimal fibrin content was also performed. Results: On the 2nd day, neointimal thickness, percentage of neointimal area, and inflammatory and intimal fibrin content scores were not significantly different between the two groups. On the 14th day, the inflammatory and intimal fibrin content scores were significantly lower in Synergy™ versus those observed in Promus PREMIER™. In Synergy™, smooth muscle cells were found and the neointimal layers were smooth. In contrast, inflammatory cells were observed surrounding the struts of Promus PREMIER™. Conclusions: These results demonstrate that termination of reactive inflammation is accelerated after abluminal coating stent versus implantation of conformal coating stent.


Assuntos
Vasos Coronários , Stents Farmacológicos , Inflamação/prevenção & controle , Neointima/imunologia , Stents/efeitos adversos , Enxerto Vascular/instrumentação , Implantes Absorvíveis , Animais , Materiais Revestidos Biocompatíveis/farmacologia , Vasos Coronários/imunologia , Vasos Coronários/cirurgia , Portadores de Fármacos/farmacologia , Everolimo/farmacologia , Inflamação/etiologia , Modelos Anatômicos , Polímeros/farmacologia , Suínos
5.
Medicine (Baltimore) ; 99(19): e19972, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32384447

RESUMO

The objective of this proof-of-concept study was to demonstrate the targeted delivery of erythropoietin (EPO) using magnetically guided magnetic nanoparticles (MNPs).MNPs consisting of a ferric-ferrous mixture (FeCl3·6H2O and FeCl2·4H2O) were prepared using a co-precipitation method. The drug delivery system (DDS) was manufactured via the spray-drying technique using a nanospray-dryer. The DDS comprised 7.5 mg sodium alginate, 150 mg MNPs, and 1000 IU EPO.Scanning electron microscopy revealed DDS particles no more than 500 nm in size. Tiny particles on the rough surfaces of the DDS particles were composed of MNPs and/or EPO, unlike the smooth surfaces of the only alginate particles. Transmission electron microscopy showed the tiny particles from 5 to 20 nm in diameter. Fourier-transform infrared spectroscopy revealed DDS peaks characteristic of MNPs as well as of alginate. Thermal gravimetric analysis presented that 50% of DDS weight was lost in a single step around 500°C. The mode size of the DDS particles was approximately 850 nm under in vivo conditions. Standard soft lithography was applied to DDS particles prepared with fluorescent beads using a microchannel fabricated to have one inlet and two outlets in a Y-shape. The fluorescent DDS particles reached only one outlet reservoir in the presence of a neodymium magnet. The neurotoxicity was evaluated by treating SH-SY5Y cells in 48-well plates (1 × 10 cells/well) with 2 µL of a solution containing sodium alginate (0.075 mg/mL), MNPs (1.5 mg/mL), or sodium alginate + MNPs. A cell viability assay kit was used to identify a 93% cell viability after MNP treatment and a 94% viability after sodium alginate + MNP treatment, compared with the control. As for the DDS particle neurotoxicity, a 95% cell viability was noticed after alginate-encapsulated MNPs treatment and a 93% cell viability after DDS treatment, compared with the control.The DDS-EPO construct developed here can be small under in vivo conditions enough to pass through the lung capillaries with showing the high coating efficiency. It can be guided using magnetic control without displaying significant neurotoxicity in the form of solution or particles.


Assuntos
Portadores de Fármacos/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Eritropoetina/farmacologia , Nanopartículas de Magnetita , Materiais Revestidos Biocompatíveis/farmacologia , Meios de Contraste , Fármacos Hematológicos/farmacologia , Humanos , Nanopartículas de Magnetita/química , Nanopartículas de Magnetita/uso terapêutico , Teste de Materiais , Microscopia Eletrônica de Varredura/métodos , Tamanho da Partícula , Propriedades de Superfície , Traumatismos do Sistema Nervoso/terapia
6.
Nanotoxicology ; 14(3): 289-309, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32193966

RESUMO

Titanium (Ti) and its alloys are widely used in clinical practice as preferred materials for bone tissue repair and replacement because of their good mechanical properties; however, as Ti lacks biological activity, clinical application has been limited. Herein, we prepared a manganese-titanium dioxide (Mn-TiO2) microporous biotic coating on Ti surfaces by micro-arc oxidation (MAO). The coating showed good surface topography and was uniformly doped with Mn, and the Mn ions were slowly released. In vitro, the Mn-TiO2 microporous biotic coating promoted the adhesion, proliferation, differentiation, and mineralization of MC3T3-E1 osteoblasts. Moreover, in vivo experiments showed that the coating promoted early osseointegration. We also conducted a preliminary investigation to explore the molecular mechanism underlying the regulation of the function of osteoblasts by the coating. Furthermore, we found that the coating could inhibit the growth of Escherichia coli in vitro, demonstrating reliable antibacterial ability. To conclude, Mn-TiO2 microporous biotic coating can improve the biological activity of Ti implants, which can potentially improve their clinical applications.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Manganês/química , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Próteses e Implantes , Titânio/química , Animais , Antibacterianos/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Íons , Osteoblastos/efeitos dos fármacos , Oxirredução , Porosidade , Coelhos , Propriedades de Superfície
7.
Carbohydr Polym ; 235: 115973, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32122505

RESUMO

This work was designed to develop the chitosan-based melatonin layer-by-layer assembly (CMLLA) via the inclusion method. The structural characterizations and interaction present in CMLLA were investigated by the scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier Transform-Infrared spectroscopy (FTIR). The ratio of chitosan (CH) to carboxymethylcellulose (CMC) greatly influenced the mechanical properties, including the tensile strength, moisture content and color performance. Results showed that both antioxidant and antimicrobial properties of CMLLA were enhanced with the addition of melatonin (MLT). Furthermore, it was demonstrated that the CMLLA with 1.2 % (w/v) CH, 0.8 % (w/v) CMC and 50 mg/L MLT better contributed to the delay of chlorophyll degradation and the maintenance of shelf-life quality. Results from this study might open up new insights into the approaches of quality improvement of postharvest fresh products by incorporating the natural antioxidant compounds into natural polymers.


Assuntos
Antibacterianos/química , Antioxidantes/química , Quitosana/química , Materiais Revestidos Biocompatíveis/química , Bicamadas Lipídicas/química , Melatonina/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Antioxidantes/síntese química , Antioxidantes/farmacologia , Compostos de Bifenilo/antagonistas & inibidores , Configuração de Carboidratos , Quitosana/farmacologia , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/farmacologia , Escherichia coli/efeitos dos fármacos , Bicamadas Lipídicas/síntese química , Bicamadas Lipídicas/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Melatonina/farmacologia , Tamanho da Partícula , Picratos/antagonistas & inibidores , Salmonella enteritidis/efeitos dos fármacos , Propriedades de Superfície , Resistência à Tração
8.
Sci Rep ; 10(1): 3247, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094428

RESUMO

Graphene based materials (GBMs) have potentials for dental and medical applications. GBMs may cause changes in the levels of cytokine released in the body. This study aimed to study the corrosion resistance of graphene oxide (GO) and GO/silver (GO/Ag) nanocomposite coated nickel-titanium (NiTi) alloy by electrophoretic deposition and to access the viability of human pulp fibroblasts, and the interleukin (IL)-6 and IL-8 expression level. The bare and coated NiTi samples were characterized by scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), Raman spectroscopy, surface profilometry, and X-ray diffraction (XRD). The corrosion resistance of the bare NiTi and coated NiTi samples were investigated by potentiodynamic polarization and electrochemical impedance spectroscopy in 3.5% NaCl solution. The cell viability of human pulp fibroblasts was accessed by the treated culture medium of the bare NiTi and coated NiTi alloys containing 1% fetal bovine serum. IL-6 and IL-8 expression levels were studied by human enzyme-linked immunosorbent assay (ELISA). Data were analyzed using One-way ANOVA (α  =  0.05). Both the GO-coated NiTi and GO/Ag-coated NiTi alloys showed better corrosion resistance, a lower rate of corrosion, and higher protection efficiency than the bare NiTi alloy. The coated NiTi alloys were biocompatible to human pulp fibroblasts and showed upregulation of IL-6 and IL-8 levels.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Fibroblastos/metabolismo , Grafite/farmacologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Boca/citologia , Níquel/farmacologia , Prata/farmacologia , Titânio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Corrosão , Polpa Dentária/citologia , Espectroscopia Dielétrica , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Humanos , Padrões de Referência , Espectrometria por Raios X , Difração de Raios X
9.
Colloids Surf B Biointerfaces ; 188: 110783, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32004907

RESUMO

The failure of dental implants is usually caused by bacteria infection, poor bioactivity and biocompatibility. It is a common phenomenon clinically. Statherin, a salivary protein, plays a crucial role of mediator between materials and cells/bacteria. However, the conformation of statherin might be changed by the implants in vivo. In this study, we investigated the effects of statherin on the bioactivities, antibacterial abilities and biocompatibilities of the titanium metals and the reaction mechanism. We found that the conformation of statherin was mainly influenced by surface composition, surface structure, surface roughness, surface hydrophilia and Ti-OH groups of materials. Statherin could decrease the cell biocompatibility of the titanium metals including pure titanium (PT), anodic oxidation (AO), sandblasting and etching (SLA) and plasma spraying hydroxyapatite (HA) coating in HGF cell experiments, regulate the bio-mineralization ability of HA coating in SBF, and enhance the antibacterial properties of PT and HA coating. This study revealed that surface properties of materials could change the conformation of statherin, which influenced the bioactivities, antibacterial properties and biocompatibilities of the materials in return.


Assuntos
Antibacterianos/metabolismo , Materiais Revestidos Biocompatíveis/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Titânio/metabolismo , Adsorção , Antibacterianos/química , Antibacterianos/farmacologia , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Conformação Proteica , Proteínas e Peptídeos Salivares/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Propriedades de Superfície , Titânio/química , Titânio/farmacologia
10.
ACS Appl Mater Interfaces ; 12(8): 9070-9079, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32009376

RESUMO

The development of nonfouling and antimicrobial materials has shown great promise for reducing thrombosis and infection associated with medical devices with aims of improving device safety and decreasing the frequency of antibiotic administration. Here, the design of an antimicrobial, anti-inflammatory, and antithrombotic vascular catheter is assessed in vivo over 7 d in a rabbit model. Antimicrobial and antithrombotic activity is achieved through the integration of a nitric oxide donor, while the nonfouling surface is achieved using a covalently bound phosphorylcholine-based polyzwitterionic copolymer topcoat. The effect of sterilization on the nonfouling nature and nitric oxide release is presented. The catheters reduced viability of Staphylococcus aureus in long-term studies (7 d in a CDC bioreactor) and inflammation in the 7 d rabbit model. Overall, this approach provides a robust method for decreasing thrombosis, inflammation, and infections associated with vascular catheters.


Assuntos
Antibacterianos , Infecções Relacionadas a Cateter/prevenção & controle , Cateteres , Materiais Revestidos Biocompatíveis , Óxido Nítrico , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/crescimento & desenvolvimento , Trombose/prevenção & controle , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Óxido Nítrico/química , Óxido Nítrico/farmacologia , Coelhos
11.
Biomater Sci ; 8(7): 1815-1829, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32016181

RESUMO

Multifarious strategies have been proposed to enhance the antibacterial ability of implant surfaces for preventing bacterial infection, however, developing facile and universal modification methods still remains extremely elusive. Herein, inspired by the fact that the electron transfer respiratory chain of bacteria is embedded in the membrane, we proposed a novel strategy of local alkalinity disturbing bacterial respiration to endow implant materials with antibacterial ability. As a demonstration, MgO was deposited on biomedical titanium via magnetron sputtering to regulate surface alkalinity. With the thickness of MgO films increasing, they exhibited an excellent antibacterial rate against both Gram-negative and positive bacteria. The antibacterial mechanism confirmed that the alkaline surface can disturb the bacterial respiration action via weakening the transmembrane proton concentration gradient, resulting in the blockage of energy metabolism and the increase of oxidative stress of bacteria. Cell experiments indicated that MgO films not only have no obvious cytotoxicity to osteoblast cells, but can also selectively kill bacteria and promote cell proliferation in the presence of both bacteria and cells. More importantly, the by-product of MgO was only the biocompatible Mg2+, reducing any concerns about potential toxic effects. Furthermore, sputtering alkaline MgO films was confirmed to work well on polyetheretherketone polymer and zirconia ceramic implants, which indicates that this strategy has broad prospects of clinical application for preventing implant-associated bacterial infection.


Assuntos
Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Contaminação de Equipamentos/prevenção & controle , Próteses e Implantes/microbiologia , Titânio/química , Animais , Antibacterianos/química , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Escherichia coli/efeitos dos fármacos , Óxido de Magnésio , Teste de Materiais , Camundongos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Propriedades de Superfície , Molhabilidade
12.
ACS Appl Mater Interfaces ; 12(8): 9718-9725, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32027112

RESUMO

Bacterial infection is the main cause of implantation failure worldwide, and the importance of antibiotics on medical devices has been undermined because of antibiotic resistance. Antimicrobial hydrogels have emerged as a promising approach to combat infections associated with medical devices and wound healing. However, hydrogel coatings that simultaneously possess both antifouling and antimicrobial attributes are scarce. Herein, we report an antimicrobial hydrogel that incorporates adhesion-inhibiting polyethylene glycol (PEG) and colony-suppressing chitosan (CS) as a dressing to combat bacterial infections. These two polymers have important environmentally benign characteristics including low toxicity, low volatility, and biocompatibility. Although hydrogels containing PEG and CS have been reported for applications in the fields of wound dressing, tissue repair, water purification, drug delivery, and scaffolds for bone regeneration, there still has been no report on the application of CS/PEG hydrogel coatings in dental applications. Herein, this biointerface shows superior activity in early-stage adhesion inhibition (98.8%, 5 h) and displays remarkably long-lasting colony-suppression activity (93.3%, 7 d). Thus, this novel nanomaterial, which has potential as a dual-functional platform with integrated antifouling and antimicrobial functions with excellent biocompatibility, might be used as a safe and effective antimicrobial coating in biomedical device applications.


Assuntos
Anti-Infecciosos , Aderência Bacteriana/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Hidrogéis , Braquetes Ortodônticos/microbiologia , Streptococcus mutans/crescimento & desenvolvimento , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Hidrogéis/química , Hidrogéis/farmacologia
13.
Molecules ; 25(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075064

RESUMO

Freestanding films based on catechol functionalized chitosan (CHI), hyaluronic acid (HA), and bioglass nanoparticles (BGNPs) were developed by spin-coating layer-by-layer assembly (SA-LbL). The catechol groups of 3,4-dihydroxy-l-phenylalanine (DOPA) present in the marine mussels adhesive proteins (MAPs) are the main factors responsible for their characteristic strong wet adhesion. Then, the produced films were cross-linked with genipin to improve their stability in wet state. Overall, the incorporation of BGNPs resulted in thicker and bioactive films, hydrophilic and rougher surfaces, reduced swelling, higher weight loss, and lower stiffness. The incorporation of catechol groups onto the films showed a significant increase in the films' adhesion and stiffness, lower swelling, and weight loss. Interestingly, a synergetic effect on the stiffness increase was observed upon the combined incorporation of BGNPs with catechol-modified polymers, given that such films were the stiffest. Regarding the biological assays, the films exhibited no negative effects on cellular viability, adhesion, and proliferation, and the BGNPs seemed to promote higher cellular metabolic activity. These bioactive LbL freestanding films combine enhanced adhesion with improved mechanical properties and could find applications in the biomedical field, such as guided hard tissue regeneration membranes.


Assuntos
Materiais Biomiméticos/química , Materiais Revestidos Biocompatíveis/química , Nanopartículas/química , Polissacarídeos/farmacologia , Adesivos/química , Adesivos/farmacologia , Catecóis/química , Adesão Celular/efeitos dos fármacos , Cerâmica/química , Quitosana/química , Materiais Revestidos Biocompatíveis/farmacologia , Ácido Hialurônico/química , Teste de Materiais , Membranas Artificiais , Polímeros/química , Polissacarídeos/química , Proteínas/química
14.
Mater Sci Eng C Mater Biol Appl ; 108: 110192, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923966

RESUMO

This study provided an eco-friendly manufacturing method for Ti implants by combining machining and surface treatment processes. Ti was machined by electrical discharge machining (EDM) in a water-based dielectric in order to reduce environmental impact and improve operational health. The feasibility of this eco-friendly EDM was evaluated by tested the bioactivity and cytocompatibility of the EDM-treated Ti and the commercially micro-arc oxidation (MAO)-treated Ti was used as a control group. Pulsed MAO and EDM treatments were applied on Ti in an aqueous solution containing hydroxyapatite (HA) with the same concentration (30 g/L) under the same voltage and treatment period. The two surface modification processes were compared from the aspects of surface composition, coating structure, and coating adhesion. Furthermore, in vitro bioactivity and cellular biocompatibility of the MAO- and EDM-treated Ti films were tested. Both treatments produced Ti oxide containing Ca and P on Ti, and the EDM-formed film possessed more Ca, with its Ca/P value closer to HA, as compared to the MAO-formed film. The MAO-formed films had micropores and nanopores in the middle region and film/substrate interface, respectively. Pores only existed on the surface of the EDM-formed films. The MAO-formed films were fractured, but the EDM-formed films maintained their original structure under tensile stress, tested according to the ASTM C633 standard. The bioactivity of the EDM-treated surface was higher than that of the MAO-treated and untreated Ti surface. After 24 h cell incubation, the EDM-treated surface exhibited a significantly higher number of cells than untreated Ti and the MAO-treated surface.


Assuntos
Materiais Revestidos Biocompatíveis , Técnicas Eletroquímicas , Teste de Materiais , Osteoblastos/metabolismo , Titânio , Linhagem Celular , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Estudos de Viabilidade , Humanos , Osteoblastos/citologia , Oxirredução , Propriedades de Superfície , Titânio/química , Titânio/farmacologia
15.
Mater Sci Eng C Mater Biol Appl ; 108: 110345, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31924041

RESUMO

Carbon Nanotubes (CNTs) are known for effective adhesion, growth, and differentiation of bone, muscle, and cardiac cells. CNTs can provide excellent mechanical and electrical properties for cell scaffolding; however, loose CNTs can cause in-vivo toxicity. To suppress this risk, our team has developed biomimetic scaffolds with multiscale hierarchy where carpet-like CNT arrays are covalently bonded to larger biocompatible substrates. In this study, we investigated the interaction between glioblastoma multiforme (GBM) cells (U87MG) and our unique hierarchical CNT-coated scaffolds upon brain tumor cell proliferation. U87MG cells grown on un-modified carbon scaffolds grew in a bi-phasic fashion. Initially, the scaffolds prevented GBM cell growth; however, prolonged growth on such scaffolds significantly increased GBM cell proliferation. We further defined the importance of the hydrophobicity/hydrophilicity of the CNT-coated scaffolds in this cellular response by utilizing sodium-hypochlorite based bleach treatment prior to cellular exposure. This surface modification increased the hydrophilicity of the CNT-coated scaffolds and ameliorated the biphasic response of U87MG cells allowing for a normal growth curve. Findings highlight the importance of surface modification and wettability of the CNT-coated scaffolds for cell growth applications. The focus for this study was to determine whether scaffold surface features could modulate tumor-scaffold interactions, and thus to improve our understanding of and optimize successful development of future scaffold-based chemotherapy applications. Overall, it appears that the wettability of carbon scaffolds coated with CNTs is an important regulator of U87MG cellular growth. These findings will be important to consider when developing a potential chemotherapy-attached implant to be used post-surgical resection for GBM patient treatment.


Assuntos
Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Glioblastoma , Nanotubos de Carbono/química , Tecidos Suporte/química , Linhagem Celular Tumoral , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Glioblastoma/metabolismo , Glioblastoma/patologia , Glioblastoma/terapia , Humanos
16.
Biomed Mater Eng ; 30(5-6): 559-567, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31929132

RESUMO

BACKGROUND: Surface nanostructures in titanium (Ti) oral implants are critical for rapid osseointegration. OBJECTIVE: The purpose of this study was to evaluate the growth of osteoblast-like (Saos-2) and epithelial-like (Ca9-22) cells on nanopatterned Ti films. METHODS: Ti films with 500 nm grooves and pillars were fabricated by nanoimprinting, and seeded with Saos-2 and Ca9-22 cells. Cell viability and morphology were assessed by cell proliferation assay and scanning electron microscopy, respectively. RESULTS: As assessed after 1 hour, proliferation of Saos-2 cells was most robust on grooved films than on pillared and smooth films, in this order. These cells approximately doubled on grooved and pillared substrates in 24 hours and after 5 days, but not on smooth surfaces. In contrast, Ca9-22 cells favored smooth surfaces, followed by grooved and pillared films. Indeed, cells sparsely adhered to pillared films over 5 days of incubation (p < 0.05). CONCLUSIONS: The data show that Saos-2 and Ca9-22 cells respond differently to different nanostructures, and highlight the potential use of nanopatterns to promote bone regeneration or to prevent epithelial downgrowth at the implant-bone interface.


Assuntos
Adesão Celular/fisiologia , Proliferação de Células/fisiologia , Materiais Revestidos Biocompatíveis/química , Implantes Dentários , Osseointegração/fisiologia , Titânio/química , Interface Osso-Implante/fisiologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/farmacologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Humanos , Teste de Materiais , Microtecnologia , Osseointegração/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Propriedades de Superfície , Tecidos Suporte/química
17.
Nanoscale ; 12(3): 1759-1778, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31895375

RESUMO

Ultrasmall superparamagnetic iron oxide nanoparticles with a size <5 nm are emerging nanomaterials for their excellent biocompatibility, chemical stability, and tunable surface modifications. The applications explored include dual-modal or multi-modal imaging, drug delivery, theranostics and, more recently, magnetic resonance angiography. Good biocompatibility and biosafety are regarded as the preliminary requirements for their biomedical applications and further exploration in this field is still required. We previously synthesized and characterized ultrafine (average core size of 3 nm) silica-coated superparamagnetic iron oxide fluorescent nanoparticles, named sub-5 SIO-Fl, uniform in size, shape, chemical properties and composition. The cellular uptake and in vitro biocompatibility of the as-synthesized nanoparticles were demonstrated in a human colon cancer cellular model. Here, we investigated the biocompatibility of sub-5 SIO-Fl nanoparticles in human Amniotic Mesenchymal Stromal/Stem Cells (hAMSCs). Kinetic analysis of cellular uptake showed a quick nanoparticle internalization in the first hour, increasing over time and after long exposure (48 h), the uptake rate gradually slowed down. We demonstrated that after internalization, sub-5 SIO-Fl nanoparticles neither affect hAMSC growth, viability, morphology, cytoskeletal organization, cell cycle progression, immunophenotype, and the expression of pro-angiogenic and immunoregulatory paracrine factors nor the osteogenic and myogenic differentiation markers. Furthermore, sub-5 SIO-Fl nanoparticles were intravenously injected into mice to investigate the in vivo biodistribution and toxicity profile for a time period of 7 weeks. Our findings showed an immediate transient accumulation of nanoparticles in the kidney, followed by the liver and lungs, where iron contents increased over a 7-week period. Histopathology, hematology, serum pro-inflammatory response, body weight and mortality studies demonstrated a short- and long-term biocompatibility and biosafety profile with no apparent acute and chronic toxicity caused by these nanoparticles in mice. Overall, these results suggest the feasibility of using sub-5 SIO-Fl nanoparticles as a promising agent for stem cell magnetic targeting as well as for diagnostic and therapeutic applications in oncology.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Materiais Revestidos Biocompatíveis , Nanopartículas de Magnetita/química , Teste de Materiais , Células-Tronco Mesenquimais/metabolismo , Dióxido de Silício , Animais , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Feminino , Humanos , Células-Tronco Mesenquimais/citologia , Camundongos , Desenvolvimento Muscular/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Dióxido de Silício/química , Dióxido de Silício/farmacologia
18.
PLoS One ; 15(1): e0227232, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31923253

RESUMO

Additive manufactured, porous bone implants have the potential to improve osseointegration and reduce failure rates of orthopaedic devices. Substantially porous implants are increasingly used in a number of orthopaedic applications. HA plasma spraying-a line of sight process-cannot coat the inner surfaces of substantially porous structures, whereas electrochemical deposition of calcium phosphate can fully coat the inner surfaces of porous implants for improved bioactivity, but the osseous response of different types of hydroxyapatite (HA) coatings with ionic substitutions has not been evaluated for implants in the same in vivo model. In this study, laser sintered Ti6Al4V implants with pore sizes of Ø 700 µm and Ø 1500 µm were electrochemically coated with HA, silicon-substituted HA (SiHA), and strontium-substituted HA (SrHA), and implanted in ovine femoral condylar defects. Implants were retrieved after 6 weeks and histological and histomorphometric evaluation were compared to electrochemically coated implants with uncoated and HA plasma sprayed controls. The HA, SiHA and SrHA coatings had Ca:P, Ca:(P+Si) and (Ca+Sr):P ratios of 1.53, 1.14 and 1.32 respectively. Electrochemically coated implants significantly promoted bone attachment to the implant surfaces of the inner pores and displayed improved osseointegration compared to uncoated scaffolds for both pore sizes (p<0.001), whereas bone ingrowth was restricted to the surface for HA plasma coated or uncoated implants. Electrochemically coated HA implants achieved the highest osseointegration, followed by SrHA coated implants, and both coatings exhibited significantly more bone growth than plasma sprayed groups (p≤0.01 for all 4 cases). SiHA had significantly more osseointegration when compared against the uncoated control, but no significant difference compared with other coatings. There was no significant difference in ingrowth or osseointegration between pore sizes, and the bone-implant-contact was significantly higher in the electrochemical HA than in SiHA or SrHA. These results suggest that osseointegration is insensitive to pore size, whereas surface modification through the presence of an osteoconductive coating plays an important role in improving osseointegration, which may be critically important for extensively porous implants.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Implantes Experimentais , Osseointegração/efeitos dos fármacos , Porosidade , Silício/farmacologia , Estrôncio/farmacologia , Animais , Fêmur/patologia , Lasers , Teste de Materiais/métodos , Equipamentos Ortopédicos , Osseointegração/fisiologia , Ovinos , Propriedades de Superfície , Titânio/farmacologia
19.
Expert Rev Med Devices ; 17(2): 87-92, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31962054

RESUMO

Introduction: Intracranial atherosclerotic disease (ICAD) is highly prevalent and probably the most common cause of stroke worldwide. Despite best medical treatment (BMT), the rate of recurrent stroke in symptomatic ICAD patients is elevated, especially in those with high-grade stenosis. Thus, alternative treatment options are needed. So far, endovascular ICAD treatment has been considered a second-line therapy. However, recent progress in the endovascular acute stroke treatment challenges this issue. Drug-coated balloon (DCB) - percutaneous transluminal angioplasty (PTA) represents a promising alternative to BMT alone.Areas covered: In this review, current clinical studies on paclitaxel-coated DCB-PTA in symptomatic high-grade ICAD patients will be presented and discussed. Furthermore, technical profile of the different paclitaxel-coated DCB, which has been used for intracranial use (Neuro Elutax SV, Elutax '3' Neuro, and SeQuent Please NEO) are being presented.Expert opinion: Despite limited data and its experimental (off-line) use, DCB-PTA has been demonstrated to be feasible and safe in selected ICAD patients with symptomatic high-grade stenosis. DCB-PTA offers several advantages compared to alternative endovascular therapy option as well as BMT alone. Consequently, DCP-PTA might be a promising candidate for the future armamentarium in ICAD treatment.


Assuntos
Angioplastia com Balão/efeitos adversos , Angioplastia com Balão/instrumentação , Aterosclerose/terapia , Materiais Revestidos Biocompatíveis/farmacologia , Paclitaxel/farmacologia , Constrição Patológica , Estudos de Viabilidade , Humanos
20.
Mater Sci Eng C Mater Biol Appl ; 108: 110430, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923959

RESUMO

Functionalization of porous metals with antibacterial coatings is hotly pursued in recent decade. Here we fabricated a highly porous stainless steel component by selective laser melting and then coated with silver incorporated zeolite by in situ hydrothermal crystallization method. The morphology of their surface was investigated by scanning electron microscopy. The inhibition of Escherichia coli and Staphylococcus aureus were identified by bacterial viability studies after 24 h of incubation. More importantly, the obtained coatings show better osteointegration by spreading bone marrow stromal cells (BMSCs) after cultured with different scaffold extract solutions for 1, 3, and 5 days. These results suggest that silver incorporated zeolite coatings on 3D printed porous stainless steels exhibit better antibacterial activity and biocompatibility, showing potential application in the field of medical implant materials.


Assuntos
Antibacterianos , Materiais Revestidos Biocompatíveis , Escherichia coli/crescimento & desenvolvimento , Impressão Tridimensional , Prata , Aço Inoxidável , Staphylococcus aureus/crescimento & desenvolvimento , Zeolitas , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Porosidade , Prata/química , Prata/farmacologia , Aço Inoxidável/química , Aço Inoxidável/farmacologia , Zeolitas/química , Zeolitas/farmacologia
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