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1.
Int J Nanomedicine ; 14: 7987-8000, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31632013

RESUMO

Background: The hierarchical porous structure and surface topography of calcium phosphate (CaP) bioceramics have a crucial impact on their osteoinductivity. Purpose: To fabricate a biomimetic bone graft with an interconnected porous structure analogous to that of trabecular bone and a bioactive nanostructured surface with excellent osteoinductive potential. Materials and methods: A biphasic CaP (BCP) substrate with highly porous structure was fabricated by an improved sponge replication method. Surface modification was performed by uniformly depositing a hydroxyapatite (HA) nanoparticle layer to create nHA-coated BCP scaffolds. The effects of these scaffolds on osteogenic differentiation of murine bone marrow-derived stem cells (BMSCs) were investigated in vitro, and their osteoinductivity was further assessed in vivo. Results: The BCP and nHA-coated BCP scaffolds had similar trabecular bone-like architectures but different surface structures, with mean grain sizes of ~55 nm and ~1 µm, respectively. Compared with the BCP substrate, the nHA-coated BCP scaffolds favored cell adhesion and promoted osteogenic differentiation of BMSCs, as evidenced by upregulated expression of osteogenic genes, enhanced alkaline phosphatase activity, and increased osteocalcin production. This could be attributed to activation of the BMP/Smad signaling pathway, as significantly higher expression levels of BMPRI, Smad1, Smad4, and Smad5 were observed in the nHA-coated BCP group. The nHA-coated BCP scaffold not only maintained scaffold integrity but also induced ectopic bone formation when implanted into rabbit dorsal muscle in vivo for 90 days, whereas the BCP substrate underwent marked biodegradation that led to severe inflammation with no sign of osteogenesis. Conclusion: The present study demonstrates the potential of this biomimetic bone graft with a trabecular framework and nanotopography for use in orthopedic applications.


Assuntos
Proteínas Morfogenéticas Ósseas/metabolismo , Fosfatos de Cálcio/farmacologia , Cerâmica/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Nanopartículas/química , Osteogênese/efeitos dos fármacos , Proteínas Smad/metabolismo , Fosfatase Alcalina/metabolismo , Animais , Materiais Biomiméticos/farmacologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Coristoma/patologia , Durapatita/química , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/enzimologia , Células-Tronco Mesenquimais/ultraestrutura , Camundongos , Nanopartículas/ultraestrutura , Osteogênese/genética , Porosidade , Coelhos , Transdução de Sinais/efeitos dos fármacos , Tecidos Suporte/química
2.
Mater Sci Eng C Mater Biol Appl ; 104: 109933, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31499966

RESUMO

Osteoporotic bone represents - particularly in case of fractures - difficult conditions for its regeneration. In the present study, the focus was put on a degradable bone substitute material of gelatin-modified calcium and strontium phosphates facing the special demands of osteoporotic bone. The release of strontium ions from the material ought to stimulate osteoblastogenesis either direct by ion release or indirect after material resorption by increased presence and activity of osteoclasts, which subsequently stimulate osteoblasts. A new porous material was produced from calcium phosphate, strontium phosphate and a mixed phase of calcium/strontium phosphate precipitated in presence of gelatin. Initially, ion release was analyzed in standard­calcium containing (2.0 mM) and low-calcium (0.4 mM) minimum essential medium. The cultivation of human peripheral blood mononuclear cells next to the material led to formation of osteoclast-like cells, able to migrate, fuse, and differentiate. Especially, the mixed gelatin-modified calcium/strontium phosphate allowed osteoclastogenesis as proven morphologically and by real-time quantitative polymerase chain reaction (RT-qPCR). It was precisely this material that led to the best osteoblastic reaction of human bone marrow stromal cells cultured on the material. The investigations of the bone substitute material indicate active involvement in the balance of cells of the bone morphogenetic unit.


Assuntos
Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Gelatina/farmacologia , Osteoblastos/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Fosfatos/farmacologia , Estrôncio/farmacologia , Animais , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Minerais/metabolismo , Monócitos/citologia , Monócitos/efeitos dos fármacos , Osteoblastos/citologia , Osteoclastos/citologia , Osteogênese/efeitos dos fármacos , Suínos
3.
Biomed Khim ; 65(4): 339-346, 2019 Jun.
Artigo em Russo | MEDLINE | ID: mdl-31436176

RESUMO

Secretion of 21 cytokines, chemokines and growth factors (LIF, SCF, SDF-1a, SCGF-b, M-CSF, MCP-3, MIF, MIG, TRAIL, GRO-a; IL-1a, IL-2ra, IL-3, IL-12(p40), IL-16, IL-18, HGF, TNF-b, b-NGF, IFN-a2, CTACK) has been studied in vitro in the culture of human adipose-derived multipotent mesenchymal stromal cells (hAMMSCs) in conditions of its osteogenic differentiation caused by 14-day contact with calcium phosphate (CP) surface with different roughness. Bilateral X-ray amorphous CP coatings were prepared on the samples of commercially pure titanium in the anodal regime using a micro-arc method. An aqueous solution prepared from 20 wt% phosphoric acid, 6 wt% dissolved hydrohyapatite nanopowder (particle diameter 10-30 nm with single agglomerates up to 100 nm), and 9 wt% dissolved calcium carbonate was used to obtain CP coating. hAMMSCs isolated from lipoaspirate were co-cultured after 4 passages with the CP-coated samples at final concentration of 1.5´105 viable karyocytes per 1.5 mL of standard nutrition medium (without osteogenic stimulators) for 14 days (a determination of [CD45,34,14,20], CD73, CD90 и CD105 cell immunophenotype; an analysis of secretory activity) and 21 days (alizarin red S staining of culture) with medium replacement every 3-4 days. Under conditions of in vitro contact with rough CP coating hAMMSCs differentiated into osteoblasts synthesizing the mineralized bone matrix; this was accompanied by 2-3-fold increasing ratio of [CD45,34,14,20]+ hemopoietic cells. The following humoral factors of hemopoietic niches acted as the signal molecules escalating in vitro the hemopoietic base in 14 days of differentiating three-dimensional culture of hAMMSCs: either leukemia inhibitory factor (LIF) and stem cell factor (SCF) cytokines under mean index of CP roughness Ra=2.4-2.6 mm or stromal derived factor-1 (SDF-1a, CXCL12 chemokine) under Ra=3.1-4.4 mm.


Assuntos
Fosfatos de Cálcio/farmacologia , Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Osteogênese , Células-Tronco Pluripotentes/citologia , Tecido Adiposo/química , Células Cultivadas , Quimiocinas/metabolismo , Citocinas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Células Estromais/citologia
4.
Mater Sci Eng C Mater Biol Appl ; 103: 109775, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31349455

RESUMO

Bioglass-calcium phosphate cement (CPC) composite materials have recently received increased attention for bone regeneration purposes, owing to their improved properties in term of biocompatibility and bone ingrowths. In this study, an injectable bone substitute (IBS) system which utilizes bioglass microspheres incorporated into brushite based cement, was evaluated. The microspheres were synthesized with a simple and low sintering temperature process; there was no significant phase difference shown from the powder and good interactivity with cells was obtained. Furthermore, physical properties were optimized in microsphere incorporated brushite cement in order to investigate in vitro and in vivo performance. Accordingly, setting time and compressive strength were hardly altered until a microsphere content of 40% (v/v) was reached. The brushite (BR)/bioglass microsphere (BM) system showed excellent bioactivity to the in-vitro simulated body fluid test: dissolution ions from composite materials influenced apatite growth, countered acidic pH, and increased material degradation. In an in-vitro study with preosteoblasts (MC3T3-E1), BR/BM supported cell adhesion and proliferation, while cell differentiation experiments without osteogenic supplements, demonstrated that BR/BM induced osteogenic differentiation. A post-implantation study conducted in femoral defects showed higher materials degradation and bone formation in BR/BM than in BR. The faster dissolution of bioglass microspheres increased BR/BM composite resorption and hence facilitated bone tissue integration. Our findings suggest that bioglass microspheres incorporated in cement could potentially be used as an injectable bone substitute for bone regeneration applications.


Assuntos
Cimentos para Ossos , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio , Cerâmica , Fêmur , Microesferas , Animais , Cimentos para Ossos/química , Cimentos para Ossos/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Linhagem Celular , Cerâmica/química , Cerâmica/farmacologia , Avaliação Pré-Clínica de Medicamentos , Fêmur/lesões , Fêmur/metabolismo , Fêmur/patologia , Camundongos , Coelhos
5.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315225

RESUMO

Cariogenic oral biofilms are strongly linked to dental caries around dental sealants. Quaternary ammonium monomers copolymerized with dental resin systems have been increasingly explored for modulation of biofilm growth. Here, we investigated the effect of dimethylaminohexadecyl methacrylate (DMAHDM) on the cariogenic pathogenicity of Streptococcus mutans (S. mutans) biofilms. DMAHDM at 5 mass% was incorporated into a parental formulation containing 20 mass% nanoparticles of amorphous calcium phosphate (NACP). S. mutans biofilms were grown on the formulations, and biofilm inhibition and virulence properties were assessed. The tolerances to acid stress and hydrogen peroxide stress were also evaluated. Our findings suggest that incorporating 5% DMAHDM into 20% NACP-containing sealants (1) imparts a detrimental biological effect on S. mutans by reducing colony-forming unit counts, metabolic activity and exopolysaccharide synthesis; and (2) reduces overall acid production and tolerance to oxygen stress, two major virulence factors of this microorganism. These results provide a perspective on the value of integrating bioactive restorative materials with traditional caries management approaches in clinical practice. Contact-killing strategies via dental materials aiming to prevent or at least reduce high numbers of cariogenic bacteria may be a promising approach to decrease caries in patients at high risk.


Assuntos
Antibacterianos/farmacologia , Biofilmes , Cimentos Dentários/química , Metacrilatos/farmacologia , Streptococcus mutans/efeitos dos fármacos , Ácidos/farmacologia , Antibacterianos/química , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Peróxido de Hidrogênio/farmacologia , Metacrilatos/química , Streptococcus mutans/patogenicidade , Streptococcus mutans/fisiologia
6.
Pol J Vet Sci ; 22(2): 243-250, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31269346

RESUMO

The purpose of the study was to assess the effect of autologous activated platelet-rich plasma on healing of a bone substitute - tricalcium phosphate hydroxyapatite in experimental long bone defects using an animal model. The experiment involved an animal model of femoral defect. 24 Termond white rabbits were used in the study. We evaluated the effect of autologous platelet-rich plasma on tricalcium phosphate using classical radiology, micro-CT studies, strength tests and histological evaluation. Radiological and histological assessment did not show a beneficial effect of PRP together with a bone substitute in comparison to filling the defects only with bone replacement material. The only benefit of adding platelet-rich plasma to a bone substitute was shown in microCT imaging. Autologous, activated platelet-rich plasma combined with hydroxyapatite tricalcium phosphate has a positive effect on the remodeling of the newly formed bone tissue, increasing its density.


Assuntos
Osso e Ossos/lesões , Fosfatos de Cálcio/farmacologia , Durapatita/farmacologia , Plasma Rico em Plaquetas , Cicatrização/efeitos dos fármacos , Animais , Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/administração & dosagem , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/administração & dosagem , Durapatita/administração & dosagem , Masculino , Coelhos , Tecidos Suporte
7.
J Craniofac Surg ; 30(4): 1308-1313, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31163569

RESUMO

The aim of this study was to investigate the effects of Bioglue as a mechanical barrier with or without biphasic calcium phosphate (BCP) in a rat tibia model. Sixty Sprague Dawley male rats weighing 250 ±â€Š20 g and 10 to 12 weeks of age were studied. Unicortical defects were created on the right tibia of all rats. Subjects were randomly divided into 3 groups. BioGlue group (24 rats); BioGlue alone, Graft group (24 rats); BioGlue + BCP and Control group; unfilled and uncovered (12 rats). Animals were euthanized at 7th, 21st, and 45th days postoperatively for histological and histomorphometric analyses. BioGlue material exhibited no adverse effects until the end of observation period. Bone-healing scores did not differ statistically between Control and BioGlue group, but found to be lower in Graft group on 21st and 45th days, (P < 0.001 and P < 0.01 on the 21st day and P < 0.01 and P < 0.05 on the 45th day, respectively). New bone formation in Graft group was found to be statistically different from Control group on the 7th and 21st days (P < 0.01 and P < 0.05 respectively), whereas no statistical difference was observed between BioGlue and Control group at all times. The present analysis indicates that BioGlue functioned well as a mechanical barrier allowing new bone formation. No additional benefit of combination treatment was detected in this study design and BCP did not offer any advantage for bone regeneration, thus it can serve as only a space maintainer.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Hidroxiapatitas/farmacologia , Proteínas/farmacologia , Adesivos Teciduais/farmacologia , Animais , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/farmacologia , Colágeno , Masculino , Osteogênese/efeitos dos fármacos , Distribuição Aleatória , Ratos Sprague-Dawley , Tíbia/cirurgia
8.
Mater Sci Eng C Mater Biol Appl ; 102: 341-361, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31147007

RESUMO

Polycaprolactone (PCL), dicalcium phosphate dihydrate (DCPD) and/or calcium silicates (CaSi) have been used to prepare highly porous scaffolds by thermally induced phase separation technique (TIPS). Three experimental mineral-doped formulations were prepared (PCL-10CaSi, PCL-5CaSi-5DCPD, PCL-10CaSi-10DCPD); pure PCL scaffolds constituted the control group. Scaffolds were tested for their chemical-physical and biological properties, namely thermal properties by differential scanning calorimetry (DSC), mechanical properties by quasi-static parallel-plates compression testing, porosity by a standard water-absorption method calcium release, alkalinizing activity, surface microchemistry and micromorphology by Environmental Scanning electronic Microscopy (ESEM), apatite-forming ability in Hank Balanced Saline Solution (HBSS) by Energy Dispersive X-ray Spectroscopy (EDX) and micro-Raman, and direct contact cytotoxicity. All mineral-doped scaffolds released calcium and alkalinized the soaking medium, which may favor a good biological (osteogenic) response. ESEM surface micromorphology analyses after soaking in HBSS revealed: pure PCL, PCL-10CaSi and PCL-10CaSi-10DCPD kept similar surface porosity percentages but different pore shape modifications. PCL-5CaSi-5DCPD revealed a significant surface porosity increase despite calcium phosphates nucleation (p < 0.05). Micro-Raman spectroscopy detected the formation of a B-type carbonated apatite (Ap) layer on the surface of PCL-10CaSi-10DCPD aged for 28 days in HBSS; a similar phase (but of lower thickness) formed also on PCL-5CaSi-5DCPD and PCL; the deposit formed on PCL-10CaSi was mainly composed of calcite. All PCL showed bulk open porosity higher than 94%; however, no relevant brittleness was observed in the materials, which retained the possibility to be handled without collapsing. The thermo-mechanical properties showed that the reinforcing and nucleating action of the inorganic fillers CaSi and DCPD improved viscoelastic properties of the scaffolds, as confirmed by the increased value of storage modulus and the slight increase in the crystallization temperature for all the biomaterials. A detrimental effect on the mechanical properties was observed in samples with the highest amount of inorganic particles (PCL-10CaSi-10DCPD). All the scaffolds showed absence of toxicity, in particular PCL-10CaSi-10DCPD. The designed scaffolds are biointeractive (release biologically relevant ions), nucleate apatite, possess high surface and internal open porosity and can be colonized by cells, creating a bone forming osteoblastic microenvironment and appearing interesting materials for bone regeneration purposes.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Compostos de Cálcio/farmacologia , Fosfatos de Cálcio/farmacologia , Poliésteres/farmacologia , Silicatos/farmacologia , Tecidos Suporte/química , Células 3T3 , Animais , Proliferação de Células/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Camundongos , Porosidade , Espectrometria por Raios X , Análise Espectral Raman , Temperatura Ambiente , Difração de Raios X
9.
ACS Appl Mater Interfaces ; 11(30): 26690-26703, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31246399

RESUMO

Calcium phosphate ceramics are frequently applied to stimulate regeneration of bone in view of their excellent biological compatibility with bone tissue. Unfortunately, these bioceramics are also highly brittle. To improve their toughness, fibers can be incorporated as the reinforcing component for the calcium phosphate cements. Herein, we functionalize the surface of poly(vinyl alcohol) fibers with thermoresponsive poly(N-isopropylacrylamide) brushes of tunable thickness to improve simultaneously fiber dispersion and fiber-matrix affinity. These brushes shift from hydrophilic to hydrophobic behavior at temperatures above their lower critical solution temperature of 32 °C. This dual thermoresponsive shift favors fiber dispersion throughout the hydrophilic calcium phosphate cements (at 21 °C) and toughens these cements when reaching their hydrophobic state (at 37 °C). The reinforcement efficacy of these surface-modified fibers was almost double at 37 versus 21 °C, which confirms the strong potential of thermoresponsive fibers for reinforcement of calcium phosphate cements.


Assuntos
Materiais Biocompatíveis/química , Cimentos para Ossos/química , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/química , Acrilamidas/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Cimentos para Ossos/síntese química , Cimentos para Ossos/farmacologia , Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Cerâmica/síntese química , Cerâmica/química , Humanos , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais , Álcool de Polivinil/química , Temperatura Ambiente
10.
Colloids Surf B Biointerfaces ; 181: 671-679, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31226642

RESUMO

The regeneration of bone-soft tissue interface, using functional membranes, remains challenging and can be promoted by improving mesenchymal stem cells (MSCs) paracrine function. Herein, a collagen membrane, used as guided bone regeneration membrane, was functionalized by calcium phosphate, chitosan and hyaluronic acid hybrid coating by simultaneous spray of interacting species process. Composed of brushite, octacalcium phosphate and hydroxyapatite, the hybrid coating increased the membrane stiffness by 50%. After 7 days of MSCs culture on the hybrid coated polymeric membrane, biological studies were marked by a lack of osteoblastic commitment. However, MSCs showed an enhanced proliferation along with the secretion of cytokines and growth factors that could block bone resorption and favour endothelial cell recruitment without exacerbating polynuclear neutrophils infiltration. These data shed light on the great potential of inorganic/organic coated collagen membranes as an alternative bioactive factor-like platform to improve MSCs regenerative capacity, in particular to support bone tissue vascularization and to modulate inflammatory infiltrates.


Assuntos
Biopolímeros/farmacologia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Colágeno/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Biopolímeros/química , Biopolímeros/metabolismo , Fosfatos de Cálcio/química , Fosfatos de Cálcio/metabolismo , Células Cultivadas , Colágeno/química , Colágeno/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , Tamanho da Partícula , Propriedades de Superfície
11.
Int J Oral Sci ; 11(2): 15, 2019 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31068570

RESUMO

Tooth decay is prevalent, and secondary caries causes restoration failures, both of which are related to demineralization. There is an urgent need to develop new therapeutic materials with remineralization functions. This article represents the first review on the cutting edge research of poly(amido amine) (PAMAM) in combination with nanoparticles of amorphous calcium phosphate (NACP). PAMAM was excellent nucleation template, and could absorb calcium (Ca) and phosphate (P) ions via its functional groups to activate remineralization. NACP composite and adhesive showed acid-neutralization and Ca and P ion release capabilities. PAMAM+NACP together showed synergistic effects and produced triple benefits: excellent nucleation templates, superior acid-neutralization, and ions release. Therefore, the PAMAM+NACP strategy possessed much greater remineralization capacity than using PAMAM or NACP alone. PAMAM+NACP achieved dentin remineralization even in an acidic solution without any initial Ca and P ions. Besides, the long-term remineralization capability of PAMAM+NACP was established. After prolonged fluid challenge, the immersed PAMAM with the recharged NACP still induced effective dentin mineral regeneration. Furthermore, the hardness of pre-demineralized dentin was increased back to that of healthy dentin, indicating a complete remineralization. Therefore, the novel PAMAM+NACP approach is promising to provide long-term therapeutic effects including tooth remineralization, hardness increase, and caries-inhibition capabilities.


Assuntos
Aminas/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Dentina/química , Nanocompostos/química , Nanopartículas , Remineralização Dentária/métodos , Cálcio , Humanos
12.
Biointerphases ; 14(3): 031001, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-31109162

RESUMO

One of the main goals of materials science in the 21st century is the development of materials with rationally designed properties as substitutes for traditional pharmacotherapies. At the same time, there is a lack of understanding of the exact material properties that induce therapeutic effects in biological systems, which limits their rational optimization for the related medical applications. This study sets the foundation for a general approach for elucidating nanoparticle properties as determinants of antibacterial activity, with a particular focus on calcium phosphate nanoparticles. To that end, nine physicochemical effects were studied and a number of them were refuted, thus putting an end to frequently erred hypotheses in the literature. Rather than having one key particle property responsible for eliciting the antibacterial effect, a complex synergy of factors is shown to be at work, including (a) nanoscopic size; (b) elevated intracellular free calcium levels due to nanoparticle solubility; (c) diffusivity and favorable electrostatic properties of the nanoparticle surface, primarily low net charge and high charge density; and (d) the dynamics of perpetual exchange of ultrafine clusters across the particle/solution interface. On the positive side, this multifaceted mechanism is less prone to induce bacterial resistance to the therapy and can be a gateway to the sphere of personalized medicine. On a more problematic side, it implies a less intense effect compared to single-target molecular therapies and a difficulty of elucidating the exact mechanisms of action, while also making the rational design of theirs for this type of medical application a challenge.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Nanopartículas/química , Nanopartículas/microbiologia , Fenômenos Químicos
13.
Artif Cells Nanomed Biotechnol ; 47(1): 1570-1576, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31007085

RESUMO

The medical community has expressed significant interest in the treatment of cartilage defect. Successful repair of articular cartilage defects remains a challenge in clinics. Due to the huge advantages of 3D micro/nanomaterials, 3D artificial micro/nano scaffolds have been widely developed and explored in the tissue repair of articular joints. In this study, chondrocyte/osteoblast-loaded ß-tricalcium phosphate (ß-TCP) bioceramic scaffold and chondrocyte-loaded ß-TCP bioceramic scaffold were prepared by micromass stem cell culture and bioreactor-based cells-loaded scaffold culture for articular cartilage defect treatment. The results demonstrate chondrocyte and osteoblast can be successfully induced from allogeneic bone marrow stromal cells using micromass stem cell culture. Further, chondrocyte-loaded ß-TCP scaffold and osteoblast-loaded ß-TCP scaffold can be successfully prepared by bioreactor-based cells-loaded scaffold culture. Finally, the scaffolds are applied for Beagle articular cartilage defect treatment. The relative cartilage regeneration abilities on Beagle femoral trochleae were as follows: Chondrocyte/osteoblast-loaded ß-TCP bioceramic scaffold group > chondrocyte-loaded ß-TCP bioceramic scaffold group > ß-TCP bioceramic scaffold. Therefore, micromass stem cell culture and bioreactor-based cells-loaded scaffold culture can be applied to prepare chondrocyte/osteoblast-loaded ß-TCP bioceramic scaffold for articular cartilage defect treatment. It suggests allogenic chondrocyte/osteoblast-loaded ß-TCP bioceramic scaffold could be potentially used in the treatment of patients with cartilage defects.


Assuntos
Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Cartilagem Articular/efeitos dos fármacos , Cerâmica/química , Condrócitos/citologia , Osteoblastos/citologia , Tecidos Suporte/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Cartilagem Articular/citologia , Cães , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Engenharia Tecidual
14.
Mater Sci Eng C Mater Biol Appl ; 100: 341-353, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948070

RESUMO

In this study porous scaffolds of chitosan (CS) and carboxymethyl cellulose (CMC) reinforced with whisker-like biphasic and triphasic calcium phosphate fibers were fabricated by freeze drying method. The effect of addition of CMC, fiber type and content on the mechanical, physicochemical and biological properties of the composite scaffolds was evaluated. The fibers were synthesized by homogenous precipitation method and were characterized. Biphasic fibers contained two phases of hydroxyapatite (HA) and monetite, and triphasic fibers consisted of HA, ß-tricalcium phosphate and calcium pyrophosphate and were 20-270 µm and 20-145 µm in length, respectively. The composite scaffolds exhibited desirable microstructures with high porosity (61-75%) and interconnected pores in range of 35-200 µm. Addition of CMC to CS led to a significant improvement in the mechanical properties (up to 150%) but did not affect the water uptake ability and biocompatibility. Both fibers improved the in vitro proliferation, attachment and mineralization of MG63 cells on scaffolds as evidenced by MTT assay, DAPI staining, SEM and Alizarin red staining. Triphasic fibers were more effective in reinforcing the scaffolds and resulted in higher cell viability. Composite scaffolds of CS and CMC reinforced with 50 wt% triphasic fibers were superior in terms of mechanical and biological properties and showed compressive strength and modulus of 150 kPa and 3.08 MPa, respectively, which is up to 300% greater than pure CS scaffolds. The findings indicate that the developed composite scaffolds are potential candidates for bone tissue engineering although they need further enhancement in mechanical properties.


Assuntos
Osso e Ossos/fisiologia , Fosfatos de Cálcio/farmacologia , Carboximetilcelulose Sódica/química , Carboximetilcelulose Sódica/farmacologia , Quitosana/química , Quitosana/farmacologia , Teste de Materiais , Engenharia Tecidual/métodos , Osso e Ossos/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Sobrevivência Celular , Humanos , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Tecidos Suporte/química , Água/química , Difração de Raios X
15.
Mater Sci Eng C Mater Biol Appl ; 100: 475-484, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948083

RESUMO

Calcium phosphate (CaP) coatings were electrochemically deposited on titanium substrates. By increasing the electrodeposition time (from 1 to 30 min), the coating thickness increases but also the surface morphology of the CaP coatings is greatly affected going from smooth to plate-like, featuring elongated plates, ribbon-like and finally sharp needle structures. Micro-stretch tests reveal that, regardless of the coating morphology and thickness, the electrodeposited CaP coatings have strong adhesion with the titanium substrates and their failure mode is cohesive failure. The effects of different morphologies on cellular behavior such as adhesion, viability, proliferation, and osteogenic gene expression were studied. The surface morphology of CaP coatings has a remarkable effect on cell attachment, proliferation, and viability. A smooth surface results in better adhesion of the cells, whereas the presence of sharp needles and ribbons on rough surfaces restricts cell adhesion and consequently cell proliferation and viability. The improved cell adhesion and viability on the smoother surface can be attributed to the higher contact area between the cell and the coating, while the needle-like morphology inflicts damage to the cells by physically disrupting the cell wall. There is no significant difference in the level of osteoblast gene expression when osteosarcoma cells are cultured on coatings with different morphologies. Our study provides crucial insights into the optimum electrodeposition procedures for CaP coating formation leading to both good cell-material interaction and sufficient mechanical properties. This can be achieved with relatively thin coatings produced by short electrodeposition times.


Assuntos
Fosfatos de Cálcio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Galvanoplastia/métodos , Teste de Materiais , Fenômenos Mecânicos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fricção , Humanos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Propriedades de Superfície
16.
Mater Sci Eng C Mater Biol Appl ; 100: 535-543, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30948090

RESUMO

In this study, zinc-sulfate-calcium-phosphate (ZSCAP) ceramics was prepared by calcination in the presence of microwave irradiation using precursors ZnSO4:ZnO:CaO:P2O5 in a ratio of 15:30:30:25 (by weight). The calcined ZSCAP ceramics was mixed with microcrystalline cellulose and it was further heated by microwave radiation for the preparation of cellulose/ZSCAP nanocomposites. It was found that microwave heating time played an important role in the crystalline phase of synthesized nanocomposites of cellulose/ZSCAP. Well-crystalline phases of calcium phosphate, zinc oxide and zinc sulfate were observed in the nanocomposites at 20 min of microwave heating time. Fourier transformed infrared spectroscopy (FTIR) and Raman spectroscopy confirmed that the obtained products were of cellulose/ZSCAP nanocomposites. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images indicated that reinforced ZSCAP nanostructures were embedded into cellulose matrix. Energy dispersive X-ray spectroscopy (EDS) further supported the presence of Zn, S, Ca and P in cellulose/ZSCAP nanocomposites. The thermal behavior of the products was studied using thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The prepared nanocomposites showed antibacterial activity against Staphylococcus aureus and Escherichia coli. In vitro cytotoxicity assay revealed that the prepared nanocomposites had no influence on proliferation of MG-63 cells. This rapid microwave-assisted method is simple, fast and suitable for the production of cellulose/ZSCAP nanocomposites, which finds its biomedical applications in tissue engineering and bone repair.


Assuntos
Tecnologia Biomédica/métodos , Fosfatos de Cálcio/síntese química , Celulose/síntese química , Micro-Ondas , Nanocompostos/química , Sulfato de Zinco/síntese química , Antibacterianos/farmacologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Celulose/química , Celulose/farmacologia , Análise Diferencial Térmica , Escherichia coli/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral Raman , Staphylococcus aureus/efeitos dos fármacos , Termogravimetria , Difração de Raios X , Sulfato de Zinco/química , Sulfato de Zinco/farmacologia
17.
Clin Oral Investig ; 23(12): 4417-4423, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31025194

RESUMO

OBJECTIVES: The aim of this study was to evaluate the mineral deposition, push-out bond strength, radiopacity, the degree of conversion, film thickness, flow, calcium ion release, and pH of experimental endodontic sealers containing hydroxyapatite (HAp), aflfa-ticalcium phosphate (α-TCP), or octacalcium phosphate (OCP) particles. MATERIALS AND METHODS: Fifty single straight root human premolars were instrumented and divided into five groups (n = 10). Experimental endodontic sealers were formulated by 70 wt% urethane dimethacrylate (UDMA), 15 wt% of glycerol-1,3-dimethacrylate (GDMA), 15 wt% of ethoxylated bisphenol A glycol dimethacrylate (BISEMA), camphorquinone (CQ), N,N-dihydroxyethyl-para-toluidine (DHEPT), and benzoyl-peroxide. 10 wt% of each HAp, α-TCP, or OCP were added to the resin and its properties were assessed. RESULTS: After 7 days, the degree of conversion ranged from 44.69% (GOCP) to 50.74% (Gcontrol) and no statistical difference were observed (p < 0.05). GAHplus showed the highest push-out bond strength 4.91 (± 2.38) MPa at 28 days of analysis (p < 0.05). Film thickness and pH were not statistically different (p > 0.05). Statically lower values of flow were found for GHAp, GOCP, and Gα-TCP (p < 0.05). Calcium deposition values were higher for GHAp at 28 days. CONCLUSIONS: Bond strength, degree of conversion, and film thickness of endodontic sealers with phosphates showed similar results compared with AHplus, but displayed higher amounts of Ca2+ release. CLINICAL RELEVANCE: Phosphate fillers improve the performance of endodontic sealers after 28 days of simulated body fluid.


Assuntos
Fosfatos de Cálcio , Metacrilatos , Materiais Restauradores do Canal Radicular , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Humanos , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacologia , Materiais Restauradores do Canal Radicular/química , Materiais Restauradores do Canal Radicular/farmacologia , Obturação do Canal Radicular
18.
Mater Sci Eng C Mater Biol Appl ; 101: 228-231, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029315

RESUMO

Magnesium substituted low crystalline ß­tricalcium phosphates (LC-ß-TCP) is an attractive biomaterials owing to its high initial osteoconductivity and bone regeneration. The present investigation is focused on fabrication of low crystalline ß-TCP (LC-ß-TCP) and evaluating in vitro dissolution toward to the crystallinity of the LC-ß-TCP. It is suggested that the crystallinity of biocompatible ceramics greatly affect into their biocompatibility. The novelty of the work is the preparation of the LC-ß-TCP without any calcium carbonate/phosphate complex, which is commonly in use. LC-ß-TCP was fabricated from MgHPO4·3H2O (MgP) and CaCl2 aqueous solution at 200 °C hydrothermal condition. In vitro dissolution evaluations simulated osteoclast condition indicated the release of Mg2+ and Ca2+. It is suggested that LC -ß-TCP fabricated by the given method could be useful material for bone regeneration because it has both low crystallinity and suitable Ca2+ and Mg2+ releasing and most importantly it does not contain any extended protocol.


Assuntos
Fosfatos de Cálcio/química , Transição de Fase , Animais , Cálcio/análise , Fosfatos de Cálcio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Força Compressiva , Cristalização , Humanos , Magnésio/análise , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Resistência à Tração , Difração de Raios X
19.
Mater Sci Eng C Mater Biol Appl ; 101: 243-253, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029317

RESUMO

Developing a simple produces for efficient derivation of motor neurons (MNs) is essential for neural tissue engineering studies. Stem cells with high capacity for neural differentiation and scaffolds with the potential to promote motor neurons differentiation are promising candidates for neural tissue engineering. Recently, human olfactory ecto-mesenchymal stem cells (OE-MSCs), which are isolated easily from the olfactory mucosa, are considered a new hope for neuronal replacement due to their neural crest origin. Herein, we synthesized conducting hydrogels using different concentration of chitosan-g-aniline pentamer, gelatin, and agarose. The chemical structures, swelling and deswelling ratio, ionic conductivity and thermal properties of the hydrogel were characterized. Scaffolds with 10% chitosan-g-aniline pentamer/gelatin (S10) were chosen for further investigation and the potential of OE-MSCs as a new source for programming to motor neuron-like cells investigated on tissue culture plate (TCP) and conductive hydrogels. Cell differentiation was evaluated at the level of mRNA and protein synthesis and indicated that conductive hydrogels significantly increased the markers related to motor neurons including Hb-9, Islet-1 and ChAT compared to TCP. Taken together, the results suggest that OE-MSCs would be successfully differentiated into motor neuron-like cells on conductive hydrogels and would have a promising potential for treating motor neuron-related diseases.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Quitosana/farmacologia , Condutividade Elétrica , Gelatina/farmacologia , Hidrogéis/farmacologia , Células-Tronco Mesenquimais/citologia , Neurônios Motores/citologia , Sefarose/farmacologia , Compostos de Anilina/síntese química , Compostos de Anilina/farmacologia , Fosfatos de Cálcio/farmacologia , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/síntese química , Quitosana/química , Força Compressiva , Gelatina/química , Humanos , Hidrogéis/química , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Neurônios Motores/efeitos dos fármacos , Bulbo Olfatório/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Termogravimetria , Tecidos Suporte/química
20.
Mater Sci Eng C Mater Biol Appl ; 98: 30-41, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30813031

RESUMO

Superparamagnetic iron oxide nanoparticles (IONPs) are promising bioactive additives to fabricate magnetic scaffolds for bone tissue engineering. To date, there has been no report on osteoinductivity of IONP-incorporated calcium phosphate cement (IONP-CPC) scaffold on stem cells using an exterior static magnetic field (SMF). The objectives of this study were to: (1) develop a novel magnetic IONP-CPC construct for bone tissue engineering, and (2) investigate the effects of IONP-incorporation and SMF application on the proliferation, osteogenic differentiation and bone mineral synthesis of human dental pulp stem cells (hDPSCs) seeded on IONP-CPC scaffold for the first time. The novel magnetic IONP-CPC under SMF enhanced the cellular performance of hDPSCs, yielding greater alkaline phosphatase activities (about 3-fold), increased expressions of osteogenic marker genes, and more cell-synthesized bone minerals (about 2.5-fold), compared to CPC control and nonmagnetic IONP-CPC. In addition, IONP-CPC induced more active osteogenesis than CPC control in rat mandible defects. These results were consistent with the enhanced cellular performance by magnetic IONP in media under SMF. Moreover, nano-aggregates were detected inside the cells by transmission electron microscopy (TEM). Therefore, the enhanced cell performance was attributed to the physical forces generated by the magnetic field together with cell internalization of the released magnetic nanoparticles from IONP-CPC constructs.


Assuntos
Fosfatos de Cálcio/química , Compostos Férricos/química , Engenharia Tecidual/métodos , Animais , Osso e Ossos/citologia , Osso e Ossos/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Humanos , Campos Magnéticos , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Osteogênese/efeitos dos fármacos , Ratos
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