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1.
Molecules ; 26(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562273

RESUMO

Diels-Alder reactions on the surface of nanoparticles allow a thermoreversible functionalization of the nanosized building blocks. We report the synthesis of well-defined magnetite nanoparticles by thermal decomposition reaction and their functionalization with maleimide groups. Attachment of these dienophiles was realized by the synthesis of organophosphonate coupling agents and a partial ligand exchange of the original carboxylic acid groups. The functionalized iron oxide particles allow a covalent surface attachment of a furfuryl-functionalized rhodamine B dye by a Diels-Alder reaction at 60 °C. The resulting particles showed the typical fluorescence of rhodamine B. The dye can be cleaved off the particle surface by a retro-Diels-Alder reaction. The study showed that organic functions can be thermoreversibly attached onto inorganic nanoparticles.


Assuntos
Corantes Fluorescentes/química , Nanopartículas de Magnetita/química , Maleimidas/química , Reação de Cicloadição , Compostos Inorgânicos/química , Maleimidas/síntese química , Rodaminas/química , Propriedades de Superfície/efeitos dos fármacos
2.
J Hosp Infect ; 109: 82-87, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33417989

RESUMO

BACKGROUND: The SARS-CoV-2 pandemic has highlighted the urgent need for safe and effective surface decontamination methods, particularly in healthcare settings. AIM: To evaluate the effectiveness of peracetic acid (PAA) dry fogging in decontaminating healthcare facility surfaces experimentally contaminated with SARS-CoV-2. METHODS: Nine materials (stainless steel, latex painted wood, unsealed hardwood, melamine countertop, vinyl flooring, clear plastic, faux leather, computer keyboard button, and smartphone touch screen) were surface contaminated with >106 median tissue culture infectious dose (TCID50) of SARS-CoV-2, and allowed to dry before exposing to PAA dry fogging. FINDINGS: When fumigated with PAA dry fog for 1 h, no infectious SARS-CoV-2 virus was recovered from any of the experimentally inoculated surface types. By contrast, high titres of infectious virus were recovered from corresponding untreated drying controls of the same materials. CONCLUSION: Standard surface decontamination processes, including sprays and wipes, are laborious and frequently cannot completely decontaminate sensitive electronic equipment. The ease of use, low cost, and overall effectiveness of a PAA dry fogging suggest that it should be considered for decontaminating healthcare settings, particularly intensive care units where severely ill SARS-CoV-2 patients are cared for.


Assuntos
Descontaminação/métodos , Desinfetantes/farmacologia , Fumigação , Instalações de Saúde , Ácido Peracético/farmacologia , SARS-CoV-2/efeitos dos fármacos , Descontaminação/instrumentação , Reutilização de Equipamento , Propriedades de Superfície/efeitos dos fármacos
3.
Carbohydr Polym ; 253: 117231, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33278989

RESUMO

The effect of graphene oxide (GO) or reduced GO (rGO) on the structure and properties of polyelectrolyte-complexed chitosan/alginate bionanocomposites is highly dependent on plasticiser type (glycerol or 1-ethyl-3-methylimidazolium acetate ([C2mim][OAc])) due to the competing interactions between the components. For the glycerol-plasticised chitosan/alginate matrix, inclusion of GO/rGO enhanced the chitosan crystallinity and increased matrix ductility. While the chitosan/alginate matrix plasticised by [C2mim][OAc] showed dramatically weakened interactions between the two biopolymers, GO was highly effective at counteracting the effect of [C2mim][OAc] by interacting with the biopolymers and the ionic liquid ions, resulting in enhanced mechanical properties and decreased surface hydrophilicity. Compared with GO, rGO was much less effective at promoting chitosan-alginate interactions and even resulted in higher surface hydrophilicity. However, irrespective of the plasticiser type, inclusion of rGO resulted in reduced crystallinity by restricting the interactions between [C2mim][OAc] and the biopolymers, and higher ionic conductivity.


Assuntos
Alginatos/química , Quitosana/química , Grafite/química , Grafite/farmacologia , Líquidos Iônicos/química , Nanocompostos/química , Plastificantes/química , Condutividade Elétrica , Glicerol/química , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Imidazóis/química , Íons/química , Estrutura Molecular , Propriedades de Superfície/efeitos dos fármacos , Temperatura de Transição
4.
PLoS One ; 15(12): e0244296, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33362209

RESUMO

There are many reports demonstrating that various derivatives of carbon nanoparticles are effective inhibitors of protein aggregation. As surface structural features of nanoparticles play a key role on modulating amyloid fibrillation process, in the present in vitro study, bovine insulin and hen egg white lysozyme (HEWL) were selected as two model proteins to investigate the reducing effect of graphene oxide quantum dots (GOQDs) on their assembly under amyloidogenic conditions. GOQDs were prepared through direct pyrolysis of citric acid, and the reduction step was carried out using ascorbic acid. The prepared nanoparticles were characterized by UV-Vis, X-ray photoelectron, and FT-IR spectroscopies, transmission electron and atomic force microscopies, zeta potential measurement, and Nile red fluorescence assay. They showed the tendencies to modulate the assembly of the proteins through different mechanisms. While GOQDs appeared to have the capacity to inhibit fibrillation, the presence of reduced GOQDs (rGOQDs) was found to promote protein assembly via shortening the nucleation phase, as suggested by ThT fluorescence data. Moreover, the structures produced in the presence of GOQDs or rGOQDs were totally nontoxic. We suggest that surface properties of these particles may be part of the differences in their mechanism(s) of action.


Assuntos
Grafite/química , Grafite/metabolismo , Oxigênio/metabolismo , Amiloide/química , Amiloide/metabolismo , Proteínas Amiloidogênicas/química , Amiloidose/metabolismo , Animais , Bovinos , Insulina/química , Modelos Biológicos , Muramidase/química , Nanopartículas/química , Oxigênio/fisiologia , Agregados Proteicos/efeitos dos fármacos , Agregados Proteicos/fisiologia , Pontos Quânticos/química , Propriedades de Superfície/efeitos dos fármacos
5.
Int J Mol Sci ; 21(24)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322781

RESUMO

Amine-coated biodegradable materials based on synthetic polymers have a great potential for tissue remodeling and regeneration because of their excellent processability and bioactivity. In the present study, we have investigated the influence of various chemical compositions of amine plasma polymer (PP) coatings and the influence of the substrate morphology, represented by polystyrene culture dishes and polycaprolactone nanofibers (PCL NFs), on the behavior of vascular smooth muscle cells (VSMCs). Although all amine-PP coatings improved the initial adhesion of VSMCs, 7-day long cultivation revealed a clear preference for the coating containing about 15 at.% of nitrogen (CPA-33). The CPA-33 coating demonstrated the ideal combination of good water stability, a sufficient amine group content, and favorable surface wettability and morphology. The nanostructured morphology of amine-PP-coated PCL NFs successfully slowed the proliferation rate of VSMCs, which is essential in preventing restenosis of vascular replacements in vivo. At the same time, CPA-33-coated PCL NFs supported the continuous proliferation of VSMCs during 7-day long cultivation, with no significant increase in cytokine secretion by RAW 264.7 macrophages. The CPA-33 coating deposited on biodegradable PCL NFs therefore seems to be a promising material for manufacturing small-diameter vascular grafts, which are still lacking on the current market.


Assuntos
Aminas/química , Materiais Revestidos Biocompatíveis/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , Nanofibras/química , Plasma/química , Polímeros/química , Aminas/efeitos adversos , Aminas/imunologia , Aminas/farmacologia , Animais , Adesão Celular/efeitos dos fármacos , Adesão Celular/imunologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/efeitos adversos , Materiais Revestidos Biocompatíveis/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/crescimento & desenvolvimento , Miócitos de Músculo Liso/metabolismo , Nanofibras/efeitos adversos , Espectroscopia Fotoeletrônica , Plasma/imunologia , Poliésteres/química , Polímeros/efeitos adversos , Polímeros/farmacologia , Células RAW 264.7 , Ratos , Propriedades de Superfície/efeitos dos fármacos , Tecidos Suporte/efeitos adversos , Tecidos Suporte/química
6.
Int J Mol Sci ; 21(22)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238458

RESUMO

Recent years have seen a marked rise in implantation into the body of a great variety of devices: hip, knee, and shoulder replacements, pacemakers, meshes, glucose sensors, and many others. Cochlear and retinal implants are being developed to restore hearing and sight. After surgery to implant a device, adjacent cells interact with the implant and release molecular signals that result in attraction, infiltration of the tissue, and attachment to the implant of various cell types including monocytes, macrophages, and platelets. These cells release additional signaling molecules (chemokines and cytokines) that recruit tissue repair cells to the device site. Some implants fail and require additional revision surgery that is traumatic for the patient and expensive for the payer. This review examines the literature for evidence to support the possibility that fibronectins and BMPs could be coated on the implants as part of the manufacturing process so that the proteins could be released into the tissue surrounding the implant and improve the rate of successful implantation.


Assuntos
Proteínas Morfogenéticas Ósseas/genética , Materiais Revestidos Biocompatíveis/uso terapêutico , Fibronectinas/genética , Próteses e Implantes , Materiais Revestidos Biocompatíveis/química , Humanos , Osseointegração/efeitos dos fármacos , Propriedades de Superfície/efeitos dos fármacos , Titânio/química , Titânio/uso terapêutico
7.
Int J Mol Sci ; 21(21)2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33167597

RESUMO

This work aimed to compare the capability of Streptococcus oralis to adhere to a novel surface, double-etched titanium (DAE), in respect to machined and single-etched titanium. The secondary outcome was to establish which topographical features could affect the interaction between the implant surface and bacteria. The samples' superficial features were characterized using scanning electron microscopy (SEM) and energy dispersive x-ray spectrometry (EDS), and the wetting properties were tested through sessile methods. The novel surface, the double-etched titanium (DAE), was also analyzed with atomic force microscopy (AFM). S. oralis was inoculated on discs previously incubated in saliva, and then the colony-forming units (CFUs), biomass, and cellular viability were measured at 24 and 48h. SEM observation showed that DAE was characterized by higher porosity and Oxygen (%) in the superficial layer and the measurement of the wetting properties showed higher hydrophilicity. AFM confirmed the presence of a higher superficial nano-roughness. Microbiological analysis showed that DAE discs, coated by pellicle's proteins, were characterized by significantly lower CFUs at 24 and 48 h with respect to the other two groups. In particular, a significant inverse relationship was shown between the CFUs at 48 h and the values of the wetted area and a direct correlation with the water contact angle. The biomass at 24 h was slightly lower on DAE, but results were not significant concerning the other groups, both at 24 and 48 h. The DAE treatment not only modifies the superficial topography and increased hydrophilicity, but it also increases the Oxygen percentage in the superficial layer, which could contribute to the inhibition of S. oralis adhesion. DAE can be considered a promising treatment for titanium implants to counteract a colonization pioneer microorganism, such as S. oralis.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Implantes Dentários/microbiologia , Streptococcus oralis/metabolismo , Titânio/química , Adesivos/metabolismo , Bactérias/metabolismo , Aderência Bacteriana/fisiologia , Biofilmes/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/química , Implantes Dentários/tendências , Humanos , Microscopia de Força Atômica/métodos , Microscopia Eletrônica de Varredura/métodos , Espectrometria por Raios X/métodos , Streptococcus oralis/patogenicidade , Propriedades de Superfície/efeitos dos fármacos
8.
J Chromatogr A ; 1634: 461655, 2020 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-33181356

RESUMO

It has been shown in previous works that the interfacial adhesion in PPTA- and PBO-epoxy composites can be improved by modifying the surface properties of these high-performance fibres upon exposure to non-oxidative plasma treatments. In this work, the effects developed on both types of polymer surface were examined as a function of treatment gas nature (He or N2) and exposure time (one or four minutes) using inverse gas chromatography at infinite dilution (IGC). From the adsorption of n-alkanes, it has been proved that non-oxidative plasma treatments led to energetically heterogeneous surfaces in the case of PPTA, and to low-energy surfaces in the case of PBO. Nevertheless, it was proved with the 1-min plasma treatments (either under helium or under nitrogen) that chemical reactivity was enhanced on the PBO surface. Such a behaviour was ascribed to the presence of low-molecular weight oxidized materials. The mechanisms involved in surface activation of PPTA were not equivalent under He or N2 exposure. Nitrogen plasma exposure led to a PPTA surface that is chemically reactive as a result of polarity enhancement. Helium plasma-treated PPTA surface was characterized by the presence of branched arrangements that intensified the number of chemical contacts onto reactive sites. Finally, for both fibre sets, if the purpose is to enhance the chemical surface reactivity, it makes no sense to increase the plasma exposure time from 1 to 4 min.


Assuntos
Cromatografia Gasosa , Gases em Plasma/farmacologia , Propriedades de Superfície/efeitos dos fármacos , Adsorção , Alcanos/química , Resinas Epóxi/química , Ácidos Ftálicos/química , Polímeros/química
9.
Biomed Res Int ; 2020: 3026893, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33005686

RESUMO

There is an increased effort on developing novel and active surfaces in order to accelerate their osteointegration, such as nanosized crystalline hydroxyapatite coating (HAnano®). To better understand the biological behavior of osteoblasts grown on HAnano® surface, the set of data was compared with SLActive®, a hydrophilic sandblasted titanium surface. Methodologically, osteoblasts were seeded on both surfaces up to 72 hours, to allow evaluating cell adhesion, viability, and set of genes encoding proteins related with adhesion, proliferation, and differentiation. Our data shows HAnano® displays an interesting substrate to support cell adhesion with typical spread morphologic cells, while SLActive®-adhering cells presented fusiform morphology. Our data shows that the cellular adhesion mechanism was accompanied with upexpression of integrin ß1, Fak, and Src, favoring the assembling of focal adhesion platforms and coupling cell cycle progression (upmodulating of Cdk2, Cdk4, and Cdk6 genes) in response to HAnano®. Additionally, both bioactive surfaces promoted osteoblast differentiation stimulus, by activating Runx2, Osterix, and Alp genes. Although both surfaces promoted Rankl gene expression, Opg gene expression was higher in SLActive® and this difference reflected on the Rankl/Opg ratio. Finally, Caspase1 gene was significantly upmodulated in response to HAnano® and it suggests an involvement of the inflammasome complex. Collectively, this study provides enough evidences to support that the nanohydroxyapatite-coated surface provides the necessary microenvironment to drive osteoblast performance on dental implants and these stages of osteogenesis are expected during the early stages of osseointegration.


Assuntos
Durapatita/farmacologia , Nanopartículas/administração & dosagem , Osseointegração/efeitos dos fármacos , Propriedades de Superfície/efeitos dos fármacos , Titânio/farmacologia , Células 3T3 , Animais , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos
10.
Int J Biol Macromol ; 165(Pt A): 1296-1302, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33002537

RESUMO

Hydrophobins are small amphipathic proteins excreted from filamentous fungi that self-assemble into the amphipathic film at hydrophobic/hydrophilic interfaces and can be used in a wide range of biotechnological application such as antimicrobial coatings, biosensors, and drug delivery. Here we describe a simple method for producing functionally active class I and class II hydrophobins in E. coli. The class I hydrophobin EAS (rodlet protein) from Neurospora crassa and class II hydrophobin HFBII from Trichoderma reesei were separately fused with fusion partner Ffu312 (ß-fructofuranosidase truncation with a native signal peptide) and successfully expressed in E. coli. Significantly, fused hydrophobins Ffu312-EAS and Ffu312-HFBII were excreted into the culture medium. The excretory expression of hydrophobins facilitated the correct disulfide-bond formation and simplified the purification. Both fusion hydrophobins reversed the glass surface hydrophilicity, reduced the water surface tension and improved emulsion stability. Ffu312 has little effect on surface coating, water surface tension and emulsion stabilization of hydrophobins. This study may provide an efficient approach for excretory and functional expression of class I and class II hydrophobins in E. coli.


Assuntos
Proteínas Fúngicas/biossíntese , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Tensoativos/química , Anti-Infecciosos/química , Técnicas Biossensoriais , Sistemas de Liberação de Medicamentos , Escherichia coli/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/farmacologia , Hypocreales/química , Hypocreales/genética , Neurospora crassa/química , Neurospora crassa/genética , Propriedades de Superfície/efeitos dos fármacos , Tensão Superficial/efeitos dos fármacos , Água/química
11.
Molecules ; 25(20)2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33076274

RESUMO

In this work we describe the relationship between surface modification of hexagonally ordered mesoporous silica SBA-15 and loading/release characteristics of nonsteroidal anti-inflammatory drug (NSAID) naproxen. Mesoporous silica (MPS) was modified with 3-aminopropyl, phenyl and cyclohexyl groups by grafting method. Naproxen was adsorbed into pores of the prepared MPS from ethanol solution using a solvent evaporation method. The release of the drug was performed in buffer medium at pH 2 and physiological solution at pH 7.4. Parent MPSs as well as naproxen loaded MPSs were characterized using physicochemical techniques such as nitrogen adsorption/desorption, thermogravimetric analysis (TG), Zeta potential analysis, Fourier transform infrared spectroscopy (FT-IR), and elemental analysis. The amount of naproxen released from the MPSs into the medium was determined by high-performance liquid chromatography (HPLC). It was shown that the adsorption and desorption characteristics of naproxen are dependent on the pH of the solution and the surface functionalization of the host.


Assuntos
Anti-Inflamatórios não Esteroides/química , Inflamação/tratamento farmacológico , Naproxeno/química , Dióxido de Silício/química , Adsorção/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/farmacologia , Sistemas de Liberação de Medicamentos , Humanos , Naproxeno/farmacologia , Porosidade , Dióxido de Silício/farmacologia , Solventes/química , Propriedades de Superfície/efeitos dos fármacos
12.
Int J Biol Macromol ; 164: 3709-3717, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32827624

RESUMO

Chitosan (CS) was cross-linked using cinnamaldehyde (Cinn) in a single step procedure following microwave irradiation to produce cinnamaldehyde-modified chitosan (Cinn-CS). The synthesized Cinn-CS was used as a novel corrosion inhibitor for copper in 1 M hydrochloric acid. A comprehensive electrochemical investigation using the impedance measurements, and potentiodynamic polarization was undertaken, supported with surface analysis and computational studies. The inhibitor Cinn-CS functioned by adsorption on the copper surface and showed an inhibition efficiency of >89% at a dose of 1000 mgL-1. The charge transfer resistance showed a rise with increase in inhibitor dosage to the corrosive medium, and the corrosion currents showed a significant decrease with the addition of the inhibitor. The Cinn-CS displayed a mixed type of inhibition performance with cathodic nature. The study of the copper surface using scanning electron microscopy depicted a considerably smooth morphology in the presence of the adsorbed Cinn-CS. The computational studies indicated that the Cinn-CS Schiff base shows better adsorption behavior compared to the parent molecules of chitosan and cinnamaldehyde and can show an inhibition performance in the neutral, and the protonated form.


Assuntos
Acroleína/análogos & derivados , Quitosana/química , Cobre/química , Propriedades de Superfície/efeitos dos fármacos , Acroleína/química , Acroleína/farmacologia , Adsorção/efeitos dos fármacos , Quitosana/farmacologia , Biologia Computacional , Corrosão , Técnicas Eletroquímicas , Ácido Clorídrico/efeitos adversos , Ácido Clorídrico/química , Microscopia Eletrônica de Varredura , Micro-Ondas , Bases de Schiff/química , Aço/química
13.
Int J Biol Macromol ; 164: 2100-2107, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758608

RESUMO

The objective of this study was to develop eco-friendly films based on poly(vinyl alcohol) (PVA) and chitosan (CTS) with the addition of plasticizer (glycerol or sorbitol) and surfactant (cocamidopropyl betaine). The properties of the obtained polymeric films were determined by contact angle measurements, attenuated total reflection infrared spectroscopy (ATR-FTIR), atomic force microscopy (AFM), mechanical tests, and moisture content analysis. The results indicated that four-component blends had high surface hydrophilicity and surface roughness due to the presence of the surfactant. Glycerol incorporation into PVA/CTS blends resulted in higher flexibility and greater water absorption capacity of the three- and four-component polymeric blends compared with these blends with sorbitol. By contrast, the addition of the surfactant to the materials is essential for their application in personal hygiene products as disposable wipes.


Assuntos
Quitosana/química , Plastificantes/química , Álcool de Polivinil/química , Tensoativos/química , Glicerol/química , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Microscopia de Força Atômica/métodos , Polímeros/química , Sorbitol/química , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Propriedades de Superfície/efeitos dos fármacos
14.
Int J Mol Sci ; 21(17)2020 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-32846976

RESUMO

The surface molecular chemistry, such as amine functionality, of biomaterials plays a crucial role in the osteogenic activity of relevant cells and tissues during hard tissue regeneration. Here, we examined the possibilities of creating amine functionalities on the surface of titanium by using the nonthermal atmospheric pressure plasma jet (NTAPPJ) method with humidified ammonia, and the effects on human mesenchymal stem cell (hMSC) were investigated. Titanium samples were subjected to NTAPPJ treatments using nitrogen (N-P), air (A-P), or humidified ammonia (NA-P) as the plasma gas, while control (C-P) samples were not subjected to plasma treatment. After plasma exposure, all treatment groups showed increased hydrophilicity and had more attached cells than the C-P. Among the plasma-treated samples, the A-P and NA-P showed surface oxygen functionalities and exhibited greater cell proliferation than the C-P and N-P. The NA-P additionally showed surface amine-related functionalities and exhibited a higher level of alkaline phosphatase activity and osteocalcin expression than the other samples. The results can be explained by increases in fibronectin absorption and focal adhesion kinase gene expression on the NA-P samples. These findings suggest that NTAPPJ technology with humidified ammonia as a gas source has clinical potential for hard tissue generation.


Assuntos
Aminas/química , Diferenciação Celular , Células-Tronco Mesenquimais/fisiologia , Gases em Plasma/farmacologia , Tecidos Suporte/química , Titânio/química , Amônia/química , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Humanos , Teste de Materiais , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Propriedades de Superfície/efeitos dos fármacos
15.
J Mater Sci Mater Med ; 31(8): 70, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32705350

RESUMO

Guided bone regeneration (GBR) is an established treatment. However, the mechanisms of GBR are not fully understood. Recently, a GBR membrane was identified that acts as a passive barrier to regenerate bone via activation and migration of macrophages (Mps) and bone marrow stem cells (BMSCs). Atmospheric pressure plasma treatment of the titanium membrane (APP-Ti) activated macrophages. The purpose of this study was to analyze whether macrophages attached to an APP-Ti membrane affected differentiation of BMSCs in a GBR model. Human THP-1 macrophages (hMps) were cultured on non-treated Ti (N-Ti) and APP-Ti membrane. Macrophage polarization was analyzed by RT-PCR and immunocytochemistry. Secreted proteins from hMps on N-Ti and APP-Ti were detected by LC/MS/MS. hBMSCs were co-cultured with hMps on N-Ti or APP-Ti and analyzed by osteogenic differentiation, Alizarin red S staining, and alkaline phosphatase (ALP) activity. N-Ti and APP-Ti membrane were also implanted into bone defects of rat calvaria. hMps on APP-Ti were polarized M2-like macrophages. hMps on N-Ti secreted plasminogen activator inhibitor-1 and syndecan-2, but hMps on APP-Ti did not. hBMSCs co-cultured with hMps on APP-Ti increased cell migration and gene expression of osteogenic markers, but suppressed mineralization, while ALP activity was similar to that of hMps on N-Ti in vitro. The volume of newly formed bone was not significantly different between N-Ti and APP-Ti membrane in vivo. M2 polarized hMps on APP-Ti suppressed osteogenic induction of hBMSCs in vitro. The indirect role of hMps on APP-Ti in newly formed bone was limited.


Assuntos
Células da Medula Óssea/citologia , Regeneração Óssea , Regeneração Tecidual Guiada , Macrófagos/fisiologia , Células-Tronco Mesenquimais/citologia , Titânio , Animais , Pressão Atmosférica , Células da Medula Óssea/imunologia , Células da Medula Óssea/metabolismo , Regeneração Óssea/efeitos dos fármacos , Regeneração Óssea/fisiologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Materiais Revestidos Biocompatíveis/síntese química , Materiais Revestidos Biocompatíveis/química , Feminino , Regeneração Tecidual Guiada/instrumentação , Regeneração Tecidual Guiada/métodos , Humanos , Teste de Materiais , Membranas Artificiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Osteogênese/efeitos dos fármacos , Osteogênese/imunologia , Gases em Plasma/farmacologia , Ratos , Ratos Sprague-Dawley , Propriedades de Superfície/efeitos dos fármacos , Células THP-1 , Titânio/química , Titânio/imunologia , Titânio/farmacologia
16.
Molecules ; 25(15)2020 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-32722440

RESUMO

The accumulation of ice on surfaces brings dangerous and costly problems to our daily life. Thus, it would be desirable to design anti-icing coatings for various surfaces. We report a durable anti-icing coating based on mussel-inspired chemistry, which is enabled via fabricating a liquid water layer, achieved by modifying solid substrates with the highly water absorbing property of sodium alginate. Dopamine, the main component of the mussel adhesive protein, is introduced to anchor the sodium alginate in order to render the coating applicable to all types of solid surfaces. Simultaneously, it serves as the cross-linking agent for sodium alginate; thus, the cross-linking degree of the coatings could be easily varied. The non-freezable and freezable water in the coatings with different cross-link degrees all remain liquid-like at subzero conditions and synergistically fulfill the aim of decreasing the temperature of ice nucleation. These anti-icing coatings display excellent stability even under harsh conditions. Furthermore, these coatings can be applied to almost all types of solid surfaces and have great promise in practical applications.


Assuntos
Hidrogéis/química , Gelo , Proteínas/química , Água/química , Alginatos/química , Dopamina/química , Dopamina/farmacologia , Hidrogéis/farmacologia , Proteínas/farmacologia , Propriedades de Superfície/efeitos dos fármacos
17.
J Mater Sci Mater Med ; 31(8): 62, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32696084

RESUMO

The aim of this study was to evaluate the effect of biofunctionalization with two TGF-ß1 inhibitor peptides, P17 and P144, on osseointegration of CP-Ti dental implants. A total of 36 implants (VEGA, Klockner®) with 3.5 × 8 mm internal connection were used in this study, divided in three groups: (1) control group (n = 12), (2) implants which surfaces were biofunctionalized with P17 peptide inhibitor (n = 12), (3) implants with surfaces biofunctionalized by P144 peptide (n = 12). Three implants, one from each group, were inserted in both hemimandibles of 6 beagle dogs, 2 months after tooth extraction. Two animals were sacrificed at 2, 4 and 8 weeks post implant insertion, respectively. The samples were analyzed by Backscattering Scanning Electron Microscopy (BS-SEM) and histological analysis. Histomorphometric analysis of bone to implant contact (BIC), peri-implant bone fraction (BF) and interthread bone (IB) were carried out. Bone formation around implants measured by quantitative analysis, BS-SEM, was significantly higher in the P17-biofunctionalized implants, 4 and 8 weeks after the implantation. Histomorphometric analysis of BIC, BF and IB showed higher values in the P17-biofunctionalized group at initial stages of healing (2 weeks) and early osseointegration both at 4 and 8 weeks. For P144 biofunctionalized implants, the histomorphometric values obtained are also higher than control group. Accordingly, better results in the experimental groups were proven both by the quantitative and the qualitative analysis. Surface biofunctionalization with TGF-ß1 inhibitor peptides, P17 and P144, resulted in better quantitative and qualitative parameters relative to implant osseointegration.


Assuntos
Materiais Revestidos Biocompatíveis/farmacologia , Implantes Dentários , Osseointegração/efeitos dos fármacos , Fragmentos de Peptídeos/química , Peptídeos/química , Receptores de Fatores de Crescimento Transformadores beta/química , Animais , Materiais Revestidos Biocompatíveis/química , Implantação Dentária Endo-Óssea , Planejamento de Prótese Dentária , Cães , Implantes Experimentais , Masculino , Mandíbula/patologia , Mandíbula/cirurgia , Teste de Materiais , Osteogênese/efeitos dos fármacos , Propriedades de Superfície/efeitos dos fármacos , Fator de Crescimento Transformador beta1/química
18.
Molecules ; 25(15)2020 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-32722602

RESUMO

Laboratory measurements of capillary pressure (Pc) and the electrical resistivity index (RI) of reservoir rocks are used to calibrate well logging tools and to determine reservoir fluid distribution. Significant studies on the methods and factors affecting these measurements in rocks containing oil, gas, and water are adequately reported in the literature. However, with the advent of chemical enhanced oil recovery (EOR) methods, surfactants are mixed with injection fluids to generate foam to enhance the gas injection process. Foam is a complex and non-Newtonian fluid whose behavior in porous media is different from conventional reservoir fluids. As a result, the effect of foam on Pc and the reliability of using known rock models such as the Archie equation to fit experimental resistivity data in rocks containing foam are yet to be ascertained. In this study, we investigated the effect of foam on the behavior of both Pc and RI curves in sandstone and carbonate rocks using both porous plate and two-pole resistivity methods at ambient temperature. Our results consistently showed that for a given water saturation (Sw), the RI of a rock increases in the presence of foam than without foam. We found that, below a critical Sw, the resistivity of a rock containing foam continues to rise rapidly. We argue, based on knowledge of foam behavior in porous media, that this critical Sw represents the regime where the foam texture begins to become finer, and it is dependent on the properties of the rock and the foam. Nonetheless, the Archie model fits the experimental data of the rocks but with resulting saturation exponents that are higher than conventional gas-water rock systems. The degree of variation in the saturation exponents between the two fluid systems also depends on the rock and fluid properties. A theory is presented to explain this phenomenon. We also found that foam affects the saturation exponent in a similar way as oil-wet rocks in the sense that they decrease the cross-sectional area of water available in the pores for current flow. Foam appears to have competing and opposite effects caused by the presence of clay, micropores, and conducting minerals, which tend to lower the saturation exponent at low Sw. Finally, the Pc curve is consistently lower in foam than without foam for the same Sw.


Assuntos
Resistência Capilar/efeitos dos fármacos , Carbonatos/química , Minerais/química , Carbonatos/farmacologia , Impedância Elétrica , Microbolhas , Minerais/farmacologia , Porosidade , Pressão , Propriedades de Superfície/efeitos dos fármacos , Água/química , Molhabilidade
19.
AAPS J ; 22(4): 83, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32495039

RESUMO

Upon systemic administration, nanoparticles encounter serum proteins in the biological system resulting in the formation of "protein corona" on the surface. Increased understanding of the relationship between nanoparticles' "chemical identity" and "biological identity" can contribute to improved clinical translation. Recent studies of protein corona composition on nanoparticles, including from our group, suggest that a strategic choice of materials can influence the types of protein adsorbed from plasma and lead to improved delivery efficiency. This mini-review reflects on the fundamental knowledge of nanoparticle protein corona and highlights the recent applications of protein corona on nanoparticles' systemic circulation, cell, and tissue-specific delivery. Important considerations on the safety and efficacy aspects pertaining to the exploration of nanoparticle protein corona's targeting effect are also summarized. Finally, the future perspectives of protein corona research are discussed.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/metabolismo , Coroa de Proteína/metabolismo , Coroa de Proteína/métodos , Animais , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Nanopartículas/administração & dosagem , Tamanho da Partícula , Ligação Proteica/fisiologia , Propriedades de Superfície/efeitos dos fármacos
20.
PLoS One ; 15(6): e0234524, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579584

RESUMO

The purpose of this study was to evaluate the adherence of streptococci to disks of titanium (commercially pure titanium: CpTi) and zirconia (tetragonal zirconia polycrystals: TZP). CpTi and yttria-stabilized TZP disks with a mirror-polished surface were used as specimens. The arithmetic mean surface roughness (Ra and Sa) and the surface wettability of the experimental specimens were measured. For analyzing the outermost layer of the experimental specimens, X-ray photoelectron spectroscopy (XPS) analysis was performed. Streptococcus sanguinis, S. gordonii, S. oralis, and S. mutans were used as streptococcal bacterial strains. These bacterial cultures were grown for 24 h on CpTi and TZP. The number of bacterial adhesions was estimated using an ATP-bioluminescent assay, and scanning electron microscope (SEM) observation of the adhered bacterial specimens was performed. No significant differences in surface roughness or wettability were found between CpTi and TZP. In XPS analyses, outermost layer of CpTi included Ti0 and Ti4+, and outermost layer of TZP included Zr4+. In the cell adhesion assay, the adherences of S. sanguinis, S. gordonii, and S. oralis to TZP were significantly lower than those to CpTi (p < 0.05); however, significant difference was not observed for S. mutans among the specimens. The adherence to CpTi and TZP of S. mutans was significantly lower than that of S. sanguinis, S. gordonii, and S. oralis. These results were confirmed by SEM. S. sanguinis, S. gordonii, and S. oralis adhered less to TZP than to CpTi, but the adherence of S. mutans was similar to both surfaces. S. mutans was less adherent compare with the other streptococci tested in those specimens.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Streptococcus sanguis/efeitos dos fármacos , Titânio/química , Zircônio/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Espectroscopia Fotoeletrônica , Streptococcus sanguis/química , Streptococcus sanguis/ultraestrutura , Propriedades de Superfície/efeitos dos fármacos , Ítrio/química
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