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1.
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
2.
Cell Prolif ; 53(1): e12725, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31746058

RESUMO

OBJECTIVES: Activation of the sympathetic system and adrenergic ß-receptors following traumatic bone defects negatively impairs bone regeneration. Whether preventing ß-receptor activation could potentially improve bone defect repair is unknown. In this study, we investigated the effect of systematic administration and local delivery of propranolol through composite scaffolds on bone healing. MATERIALS AND METHODS: Collagen/PVA/propranolol/hydroxyapatite(CPPH)composite scaffolds were fabricated with 3D printing technique and characterized by scanning electron microscope (SEM). Micro-CT analysis and bone formation histology were performed to detect new bone formation. Osteogenic differentiation of bone marrow stromal cells (BMSCs) and osteoclastogenesis of bone marrow monocytes cultured with scaffolds extract were performed for further verification. RESULTS: Intraperitoneal injection of propranolol did not significantly improve bone repair, as indicated by micro-CT analysis and bone formation histology. However, CPPH scaffolds exhibited sustained release of propranolol in vitro and significantly enhanced bone regeneration compared with vehicle collagen/PVA/hydroxyapatite (CPH) scaffolds in vivo. Moreover, in vitro experiments indicated the scaffolds containing propranolol promoted the osteogenic differentiation and migration of rat BMSCs and inhibited osteoclastogenesis by preventing ß-receptor activation. CONCLUSIONS: This study demonstrates that local adrenergic ß-receptor blockade can effectively enhance the treatment of bone defects by stimulating osteogenic differentiation, inhibiting osteoclastogenesis and enhancing BMSCs migration.


Assuntos
Antagonistas Adrenérgicos beta/farmacologia , Células da Medula Óssea/metabolismo , Regeneração Óssea/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Propranolol/farmacologia , Tecidos Suporte/química , Antagonistas Adrenérgicos beta/química , Animais , Células da Medula Óssea/patologia , Colágeno/química , Colágeno/farmacologia , Implantes de Medicamento/farmacologia , Durapatita/química , Durapatita/farmacologia , Masculino , Álcool de Polivinil/química , Álcool de Polivinil/farmacologia , Propranolol/química , Ratos , Ratos Sprague-Dawley , Células Estromais/metabolismo , Células Estromais/patologia
3.
Mater Sci Eng C Mater Biol Appl ; 107: 110306, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761228

RESUMO

Hydroxyapatite (HA) coatings onto Ti6Al4V alloy substrates were obtained by several thermal spray technologies: atmospheric plasma spray (APS) and high velocity oxy fuel (HVOF), together with the cold spray (CS) technique. A characterization study has been performed by means of surface and microstructure analyses, as well as biological performance. In-vitro tests were performed with primary human osteoblasts at 1, 7 and 14 days of cell culture on substrates. Cell viability was tested by MTS and LIVE/DEAD assays, cell differentiation by alkaline phosphatase (ALP) quantification, and cell morphology was analyzed by scanning electron microscopy. The HA coatings showed an increase of HA crystallinity from 62,4% to 89%, but also an increase of hydrophilicity from ∼32° to 0°, with the decrease of the operating temperature of the thermal spray techniques (APS > HVOF > CS). Additionally, APS HA coatings showed more surface micro-features than HVOF and CS HA coatings; cells onto APS HA coatings showed faster attachment by acquiring osteoblastic morphology in comparison with the rounded cell morphology observed onto CS HA coatings at 1 day of cell culture. HVOF HA coatings also showed proper cell adherence but did not show extended filopodia as cells onto APS HA coatings. However, at 14 days of cell culture, higher cell proliferation and differentiation was detected on HA coatings with higher crystallinity (HVOF and CS techniques). Cell attachment is suggested to be favoured by surface micro-features but also moderate surface wettability whereas cell proliferation and differentiation is suggested to be highly influenced by HA crystallinity and crystal size.


Assuntos
Materiais Revestidos Biocompatíveis/química , Durapatita/química , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Durapatita/farmacologia , Humanos , Teste de Materiais , Nanopartículas/química , Osteoblastos/efeitos dos fármacos , Propriedades de Superfície
4.
Mater Sci Eng C Mater Biol Appl ; 106: 110287, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753339

RESUMO

Polymeric vascular grafts have been widely used in the vascular regeneration field because of their ease of application. However, synthetic polymer grafts have the severe problem of low biocompatibility, which may cause delayed endothelialization and hyperplasia. In this study, we fabricated a linear hydroxyapatite (HA) pattern on a silicon wafer and then transferred the pattern to a poly(L-lactic)-acid (PLLA) film for use as a tubular vascular graft. The HA pattern with its characteristic needle-like shape was successfully embedded into the PLLA. The HA-patterned PLLA film exhibited superior mechanical stability compared with that of a HA-coated PLLA film under bending, elongation, and in vitro circulation conditions, suggesting its suitability for use as a tubular vascular graft. In addition, the HA pattern guided rapid endothelialization by promoting proliferation of endothelial cells and their migration along the pattern. The hemocompatibility of the HA-patterned PLLA was also confirmed, with substantially fewer platelets adhered on its surface. Overall, in addition to good mechanical stability, the HA-patterned PLLA exhibited enhanced biocompatibility and hemocompatibility compared with pure PLLA.


Assuntos
Durapatita/química , Teste de Materiais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Plaquetas/citologia , Plaquetas/metabolismo , Adesão Celular/efeitos dos fármacos , Durapatita/farmacologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Poliésteres/química , Tecidos Suporte/química , Enxerto Vascular/métodos
5.
Chemosphere ; 240: 124916, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31563104

RESUMO

Cadmium contamination in greenhouse vegetable fields greatly limited the sustainable production especially of leafy vegetables. Hydroxyapatite (HAP), as a common soil amendment, has been widely used in the remediation of Cd-contaminated soils, while its remediation efficiency greatly depends on its particle sizes. In this study, a rhizobag pot experiment was conducted to investigate the effects of HAP (<60 nm, <12 µm and <80 µm) on bioavailability of Cd to celery grown in acidic and slightly Cd-contaminated greenhouse soil. The results suggested that HAP with the largest particle size (<80 µm) had the best effectiveness in reducing Cd uptake especially by the edible part of celery. Specifically, the increase in HAP (<80 µm) addition from 0.5% to 3% prominently reduced Cd concentrations in celery shoot by 19.6%-76.8% as compared with the untreated group. Also, adding HAP (<80 µm) especially at 3% significantly decreased translocation factor (TF) of Cd from celery root to shoot by 30.6% and reduced bioconcentration factor (BCF) of Cd from rhizosphere soil to celery shoot by 76.4%. These were predominantly associated with the significantly increased soil pH and the subsequently decreased soil CaCl2-Cd concentration after adding HAP (<80 µm). Overall, although rhizosphere soil pH was the key factor in controlling Cd uptake by edible celery and regulating BCF and TF of Cd, insignificant root-induced acidification had limited effect on the immobilization efficiency of Cd by HAP (<80 µm). In conclusion, HAP (<80 µm) has good potential for the remediation of Cd-contaminated greenhouse soils.


Assuntos
Apium/efeitos dos fármacos , Apium/metabolismo , Cádmio/farmacocinética , Durapatita/farmacologia , Poluentes do Solo/farmacocinética , Solo/química , Apium/crescimento & desenvolvimento , Biodegradação Ambiental , Disponibilidade Biológica , Cádmio/análise , Durapatita/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/metabolismo , Rizosfera , Poluentes do Solo/análise
6.
J Endod ; 45(12): 1513-1521, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31594670

RESUMO

INTRODUCTION: The purpose of this study was to evaluate the effect of chitosan-hydroxyapatite precursor (C-HA) nanocomplex conditioning on the chemical modifications at the tricalcium silicate sealer-dentin interface using time-of-flight secondary ion mass spectrometry. METHODS: Dentin slabs from human premolar root dentin were prepared, demineralized, and randomly distributed between control and C-HA nanocomplex conditioned groups. Tricalcium silicate sealer was applied, and the slabs were allowed to set in 100% humidity for 10 days. The cross-sectional area was exposed, and the sealer-dentin interface was characterized for chemical/ultrastructural evaluation with time-of-flight secondary ion mass spectrometry and transmission electron microscopy, respectively. RESULTS: Chemical analysis revealed the presence of an ion-rich layer constituted of abundant phosphates (PO2-, PO3-, and PO4-), hydroxide (OH-), and chitosan fragments (C2H4NO-, C3H4NO2-, C2H5O2+, C2H6NO+, C4H6NO2+, C5H6NO+, and C5H5O2+) on the dentin surface at the sealer-dentin interface and subsurface dentin after conditioning with C-HA nanocomplexes. In contrast, a decreased interfacial presence of calcium (Ca+) and calcium phosphates (CaPO2+, CaPO3+, CaPO4+, and Ca2PO3+) and the absence of phosphate fragments in the control were noted. Ultrastructural evaluation showed an interfacial layer (<1 µm) with interrupted mineral aggregates in the controls as opposed to a continuous (5 µm) mineral layer formation on the conditioned dentin. CONCLUSIONS: C-HA nanocomplex conditioning of dentin before tricalcium silicate sealer application resulted in a chemically modified dentin substrate with an ion-rich layer consisting of phosphate, calcium, calcium phosphates, and chitosan that chemically modified the dentin surface/subsurface.


Assuntos
Quitosana , Dentina , Durapatita , Materiais Restauradores do Canal Radicular , Compostos de Cálcio , Quitosana/farmacologia , Dentina/efeitos dos fármacos , Durapatita/farmacologia , Humanos , Teste de Materiais , Silicatos , Espectrometria de Massa de Íon Secundário
7.
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
8.
Mater Sci Eng C Mater Biol Appl ; 105: 110102, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546340

RESUMO

The Hydroxyapatite (HA, Ca10(PO4)6(OH)2) has attracted widely research interests in many aspects, especially in repairing and replacing human hard tissues due to its brilliant biocompatibility, biological activity and so on. In the present article, HA nano-rods were rapidly developed via hydrothermal reaction synthesized with two representative surfactants (hexadecyltrimethylammonium bromide and sodium dodecyl sulfate) taken oyster shells as raw materials. The scanning electron microscopy (SEM) observations demonstrated that the micromorphology of synthesized HA was constructed of relatively regular nano-rods. From the zeta potential (ZP) analysis, the zeta potential of the developed HA was affected by different surfactants, which demonstrated the opposite potential value. The Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD) results showed the HA phase was successfully and rapidly developed on the surface of oyster shell with the help of surfactants. The bio-safety of HA nano-rods was confirmed by MTT cytotoxicity assay using pre-osteoblasts cells. A possible hard-template transformation mechanism from the calcite and aragonite phases into the HA phase was proposed.


Assuntos
Exoesqueleto/química , Crassostrea/química , Durapatita , Nanotubos/química , Osteoblastos/metabolismo , Tensoativos , Animais , Linhagem Celular , Durapatita/química , Durapatita/farmacologia , Camundongos , Osteoblastos/citologia , Tensoativos/química , Tensoativos/farmacologia
9.
Mater Sci Eng C Mater Biol Appl ; 105: 110020, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546350

RESUMO

In situ High-Temperature X-ray diffraction (HT-XRD) from 400 to 900 °C was carried out to obtain patterns of bio hydroxyapatite every 20 °C during calcination processes at heating rates of 3, 6, and 9 °C/min to determine changes in its structural parameters as well as in its thermal expansion coefficient (TEC) for a and c lattice parameters. Additionally, High-Resolution Transmission Electron microscopy (HR-TEM) demonstrates that this HAp has an ordered nano like plate crystalline structure. The raw sample exhibits broad X-ray peaks originated by its nano size, and after calcination at about 700 °C, these become narrowed due to crystal growth. The calculation of the TEC as a function of the temperature for this hydroxyapatite shows a nonlinear increment for the a and c lattice parameters. Lattice thermal expansion occurs as water and organic matter are lost as the coalescence of HAp crystals take place; furthermore, as the heating rate increases, so does the lattice volume. Thermal analyses confirm that crystal growth is a process that starts after the bone sample has lost all its organic material and then bio-hydroxyapatite size changes from nano to micro-scale. A simulation using the PDF-4 software confirmed the nanometric size of the hydroxyapatite.


Assuntos
Durapatita/química , Teste de Materiais/métodos , Difração de Raios X , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/ultraestrutura , Varredura Diferencial de Calorimetria , Bovinos , Durapatita/farmacologia , Temperatura Alta , Minerais/análise
10.
Mater Sci Eng C Mater Biol Appl ; 105: 109985, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546404

RESUMO

Ceramic/polymer-based biocomposites have emerged as potential biomaterials to fill, replace, repair or regenerate injured or diseased bone, due to their outstanding features in terms of biocompatibility, bioactivity, injectability, and biodegradability. However, these properties can be dependent on the amount of ceramic component present in the polymer-based composite. Therefore, in the present study, the influence of nanohydroxyapatite content (30 to 70 wt%) on alginate-based hydrogels was studied in order to evaluate the best formulation for maximizing bone tissue regeneration. The composite system was characterized in terms of physic-chemical properties and biological response, with in vitro cytocompatibility assessment with human osteoblastic cells and ex vivo functional evaluation in embryonic chick segmental bone defects. The main morphological characteristics of the alginate network were not affected by the addition of nanohydroxyapatite. However, physic-chemical features, like water-swelling rate, stability at extreme pH values, apatite formation, and Ca2+ release were nanoHA dose-dependent. Within in vitro cytocompatibility assays it was observed that hydrogels with nanoHA 30% content enhanced osteoblastic cells proliferation and expression of osteogenic transcription factors, while those with higher concentrations (50 and 70%) decreased the osteogenic cell response. Ex vivo data underlined the in vitro findings, revealing an enhanced collagenous deposition, trabecular bone formation and matrix mineralization with Alg-nanoHA30 composition, while compositions with higher nanoHA content induced a diminished bone tissue response. The outcomes of this study indicate that nanohydroxyapatite concentration plays a major role in physic-chemical properties and biological response of the composite system and the optimization of the components ratio must be met to maximize bone tissue regeneration.


Assuntos
Alginatos/farmacologia , Regeneração Óssea/efeitos dos fármacos , Durapatita/farmacologia , Hidrogéis/farmacologia , Nanopartículas/química , Animais , Cálcio/análise , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Íons , Células-Tronco Mesenquimais , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Água/química
11.
Nanoscale ; 11(38): 17699-17708, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31545331

RESUMO

Biomaterial topography-based strategies are regarded as an effective way to regulate the osteoimmune environment which plays an indispensable role in the bone regeneration process. The rapid development of manufacture techniques makes it possible to investigate the cell-topography interactions by preparing various micro and nano-topographical surfaces on biomaterials. Still, it is a challenge to prepare well-defined micro/nano hierarchical structures of bioceramics due to the inherent brittleness of ceramic materials. Also, the correlation between osteoimmunomodulation initiated by micro/nano hierarchical topographies and the tissue regeneration outcomes is unclear. In this study, we prepared well-defined micro/nano hierarchical structures on hydroxyapatite (HA) bioceramics through the combination of the photolithography and hydrothermal techniques. Three different microscale circular patterns (4 µm, 12 µm and 36 µm) and nanotopographies (nanoneedle, nanosheet and nanorod) were fabricated by changing the size of the mask and the condition of the hydrothermal reaction. The macrophage responses on the nanoneedle structures with different micropatterns were investigated and the micro/nano hierarchical structures with appropriate pattern sizes could either promote or alleviate the macrophage polarization, which further affected the outcomes of the osteogenic differentiation of human bone marrow stromal cells (hBMSCs) and angiogenic activity of human umbilical vein endothelial cells (HUVECs). Our study demonstrated that osteoimmunomodulation could be manipulated via tuning the micro/nano hierarchical structures, which could lead to a new strategy for the development of bone biomaterials with favorable osteoimmunomodulatory properties.


Assuntos
Células da Medula Óssea/metabolismo , Cerâmica , Durapatita , Células Endoteliais da Veia Umbilical Humana/metabolismo , Nanopartículas/química , Neovascularização Fisiológica/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Animais , Células da Medula Óssea/citologia , Cerâmica/química , Cerâmica/farmacologia , Durapatita/química , Durapatita/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Camundongos , Células RAW 264.7 , Células Estromais/citologia , Células Estromais/metabolismo
12.
Biomed Pharmacother ; 119: 109404, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31526972

RESUMO

Currently, bio-mimetic material synthetic processes are involved in bone implant design which is closely related to natural bone. In this work, Zinc, Cerium and Selenium substituted hydroxyapatite/ Poly (sorbitol sebacate glutamate) (Zn, Ce, Se-HAP/PSSG, M-HAP/PSSG) composite was prepared by sol-gel method as a bio-mimetic materials for bone implantation. The physiochemical characterizations of M-HAP/PSSG was analyzed by Fourier transform infra red (FT-IR), X-ray diffraction (XRD), Scanning electron microscopy (SEM) equipped with energy dispersive X-ray analysis (EDX) and High resolution transmission electron microscopy (HRTEM). Then, the prepared M-HAP/PSSG composite was compared with HAP/PSSG, Zn-HAP/PSSG, Ce-HAP/PSSG and Se-HAP/PSSG composites in order to evaluate the influence of single minerals on HAP matrix. Then the coating ability of the final better M-HAP/PSSG composite on surface treated titanium (Ti) was investigated to evaluate the perfection of implant material. The higher micro-hardness was observed on M-HAP/PSSG composite coated Ti (305.92 ±â€¯20.42) due to the presence of multi-minerals as well as the co-polymer PSSG when compared with M-HAP coated Ti plate (273.0 ±â€¯15.75). The bio-compatibility and osteogenic activity evaluation of all prepared composite on human osteoblasts MG-63 cells shows that the better cell attachment, proliferation and differentiation was observed by M-HAP/PSSG bio-composites when compared with other composites. Histological staining and X-ray photographs of in-vivo rat model confirms that the formation of new tibial bone when the defected rat was treated with M-HAP/PSSG composite coated Ti implant. In conclusion, the bio-composite M-HAP/PSSG is better scaffold for coating on the surface of Ti implant for orthopedic implantation.


Assuntos
Osso e Ossos/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Durapatita/farmacologia , Implantes Experimentais , Minerais/farmacologia , Sorbitol/farmacologia , Titânio/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Antibacterianos/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Durapatita/química , Dureza , Humanos , Masculino , Testes de Sensibilidade Microbiana , Osteogênese/efeitos dos fármacos , Ratos Wistar , Regeneração/efeitos dos fármacos , Sorbitol/síntese química , Sorbitol/química , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Natação , Difração de Raios X
13.
Int J Nanomedicine ; 14: 6019-6033, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534334

RESUMO

Objective: Icariin (IC) promotes osteogenic differentiation, and it may be a potential small molecule drug for local application in bone regeneration. Icariin-loaded hydroxyapatite/alginate (IC/HAA) porous composite scaffolds were designed in this study for the potential application of the sustainable release of icariin and subsequent bone regeneration. Methods: An icariin-loaded hydroxyapatite/alginate porous composite scaffold was prepared and characterized by SEM and HPLC for morphology and release behavior, respectively. The mechanical properties, degradation in PBS and cytotoxicity on BMSCs were also evaluated by MTT assay, compression strength and calculation of weight remaining ratio, respectively. Rabbit BMSCs were cocultured with IC/HAA scaffolds, and ALP activity and Alizarin Red staining were performed to evaluate osteogenic differentiation induction. The mRNA and protein expression level of an osteogenic gene was detected by RT-PCR and Western blotting, respectively. In vivo animal models of critical bone defects in the radius of rabbit were used. Four and 12 weeks after the implantation of IC/HAA scaffolds in the bone defect, radiographic images of the radius were obtained and scored by using the Lane and Sandhu X-ray scoring system. Tissue samples were also evaluated using H&E and Masson staining, and an osteogenic gene and Wnt signaling pathway genes were detected. Results: A hydroxyapatite/alginate (HAA) porous composite scaffold-loaded icariin was fabricated using a freeze-drying method. Our data indicated that the icariin was loaded in alginate scaffold without compromising the macro/microstructure or mechanical properties of the scaffold. Notably, the IC/HAA promoted the proliferation of rBMSCs without exerting cytotoxicity on rBMSCs. In vivo, rabbit radius bone defect experiments demonstrated that the IC/HAA scaffold exhibited better capacity for bone regeneration than HAA, and IC/HAA upregulated the relative expression levels of an osteogenic gene and the Wnt signaling pathway genes. Most notably, the IC/HAA scaffold also inhibited osteoclast activity in vivo. Conclusion: Our data suggests a promising application for the use of HAA scaffolds to load icariin and promote bone regeneration in situ through mediation of the coupling processes of osteogenesis induction and osteoclast activity inhibition.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Flavonoides/farmacologia , Osteoclastos/metabolismo , Osteogênese , Tecidos Suporte/química , Alginatos/farmacologia , Animais , Materiais Biocompatíveis/farmacologia , Biomarcadores/metabolismo , Morte Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Osteoclastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Porosidade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos , Rádio (Anatomia)/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos
14.
Arch Oral Biol ; 107: 104484, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31382161

RESUMO

OBJECTIVES: The aim of this study was to examine the effect of nano-hydroxyapatite (nHA) on biofilm formation by Streptococcus mutans, which is actively involved in the initiation of dental caries. DESIGN: The effects of nHA on growth and biofilm formation by S. mutans were investigated in two media: a saliva analog medium, basal medium mucin (BMM); and a nutrient-rich medium, brain heart infusion (BHI); in the presence and absence of sucrose. RESULTS: Sucrose enhanced the growth of S. mutans in both media. In the presence of sucrose, nHA enhanced bacterial growth and biofilm formation more in BMM medium than in BHI. nHA also affected the transcription of glucosyltransferase (gtf) genes and production of polysaccharide differently in the two media. In BHI medium, the transcription of all three gtf genes, coding for enzymes that synthesize soluble and insoluble glucans from sucrose, was increased more than 3-fold by nHA. However, in BMM medium, only the transcription of gtfB and gtfC, coding for insoluble glucans, was substantially enhanced by nHA. CONCLUSIONS: nHA appeared to enhance biofilm formation by increasing glucosyltransferase transcription, which resulted in an increase in production of insoluble glucans. This effect was influenced by the growth conditions.


Assuntos
Biofilmes/efeitos dos fármacos , Durapatita/farmacologia , Streptococcus mutans/crescimento & desenvolvimento , Meios de Cultura/química , Cárie Dentária , Glucosiltransferases , Nanopartículas , Streptococcus mutans/efeitos dos fármacos
15.
Nanoscale ; 11(34): 15958-15970, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31418432

RESUMO

Oral drug delivery systems (ODDSs) have attracted considerable attention in relation to orthotopic colon cancer therapy due to certain popular advantages. Unfortunately, their clinical applications are generally limited by the side-effects caused by systemic drug exposure and poor real-time monitoring capabilities. Inspired by the characteristics of pH changes of the gastrointestinal tract (GIT) and specific enzymes secreted by the colonic microflora, we anchored polyacrylic acid (PAA) and chitosan (CS) on Gd3+-doped mesoporous hydroxyapatite nanoparticles (Gd-MHAp NPs) to realize programmed drug release and magnetic resonance imaging (MRI) at the tumor sites. In particular, the grafted PAA, as a pH-responsive switch, could effect controlled drug release in the colon. Further, CS is functionalized as the enzyme-sensitive moiety, which could be degraded by ß-glycosidase in the colon. Gadolinium is a paramagnetic lanthanide element used in chelates, working as a contrast medium agent for an MRI system. Interestingly, after oral administration, CS and PAA could protect the drug-loaded nanoparticles (NPs) against variable physiological conditions in the GIT, allowing the drug to reach the colon tumor sites, preventing premature drug release. Enhanced drug concentrations at the colon tumor sites were achieved via this programmed drug release, which subsequently ameliorated the therapeutic effect. In addition, encapsulating both chemotherapeutic (5-fluorouracil, 5-FU) and targeted therapy drug (gefitinib, Gef) within Gd-MHAp NPs produced a synergistic therapeutic effect. In summary, this study demonstrated that such a novel drug system (Gd-MHAp/5-FU/Gef/CS/PAA NPs) could protect, transport, and program drug release locally within the colonic environment; further, this system exhibited a worthwhile therapeutic effect, providing a promising novel treatment strategy for orthotopic colon cancer.


Assuntos
Neoplasias do Colo , Meios de Contraste , Fluoruracila , Gadolínio , Gefitinibe , Imagem por Ressonância Magnética , Nanopartículas , Resinas Acrílicas/química , Resinas Acrílicas/farmacocinética , Resinas Acrílicas/farmacologia , Administração Oral , Animais , Quitosana/química , Quitosana/farmacocinética , Quitosana/farmacologia , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Meios de Contraste/química , Meios de Contraste/farmacocinética , Meios de Contraste/farmacologia , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Durapatita/química , Durapatita/farmacocinética , Durapatita/farmacologia , Fluoruracila/química , Fluoruracila/farmacocinética , Fluoruracila/farmacologia , Gadolínio/química , Gadolínio/farmacocinética , Gadolínio/farmacologia , Gefitinibe/química , Gefitinibe/farmacocinética , Gefitinibe/farmacologia , Células HT29 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/química , Nanopartículas/uso terapêutico
16.
J Orthop Res ; 37(12): 2655-2660, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31373384

RESUMO

Several antibacterial materials have been developed to prevent periprosthetic joint infection and thus prevent serious complications for patients and surgeons. However, no study has addressed the activity of antibacterial materials against hematogenous infection. The present study evaluated the antibacterial activity of a silver-containing hydroxyapatite-coated implant against methicillin-resistant Staphylococcus aureus (MRSA) hematogenous infection. Implants coated with hydroxyapatite and silver-hydroxyapatite were inserted into rats' right and left femurs, respectively, after which the animals were infected with S. aureus via a tail vessel. About 107 colony-forming units was the optimal bacterial number for the establishment of S. aureus hematogenous infection. Bacterial loads and C-reactive protein in the blood were measured to confirm bacteremia and inflammation. Fourteen days after the infection, bacterial loads were statistically lower in the femurs containing silver-hydroxyapatite-coated implants than in those with hydroxyapatite-coated implants (p = 0.022). Thus, silver-hydroxyapatite-coated implants might provide antibacterial activity against MRSA hematogenous infection in the postoperative period. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:2655-2660, 2019.


Assuntos
Antibacterianos/farmacologia , Durapatita/farmacologia , Fêmur/microbiologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Infecções Relacionadas à Prótese/prevenção & controle , Infecções Estafilocócicas/prevenção & controle , Animais , Materiais Revestidos Biocompatíveis , Masculino , Ratos , Ratos Sprague-Dawley , Prata/farmacologia
17.
Int J Nanomedicine ; 14: 5243-5256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409987

RESUMO

Background: Dentin hypersensitivity is a common negative oral condition that can be treated with dentifrice containing hydroxyapatite (HA). The study evaluated the effect of nano-HA dentifrice on plugging the dentinal tubules for an anti-sensitivity reaction compared to a dentifrice containing common-sized particles. Also, the adsorption capacity of different particle sizes of HA mixed in a dentifrice and which is the optimal particle size was considered. Methods: Fourty premolar dentine discs and fourty molar dentine discs were randomly divided into 4 groups: distilled water group, ordinary dentifrice group and 80, 300 nm HA dentifrice group. Each dentin disc was brushed with a dentifrice twice daily at 7600 rpm under 100 g force for 2 mins for 7 consecutive days and divided into two parts, half of the dentin disc was detected by the scanning electron microscope (SEM) and energy dispersive spectrometer (EDS), the other half was brushed with distilled water and observed by SEM. One milliliter dentifrice solution (80 nm HA dentifrice, 300 nm HA dentifrice, ordinary dentifrice) was added to 50 ml potassium dichromate solution for 1, 14, and 28 d. The residual Chromium (Cr6+) concentration in the supernatant was measured by the diphenylcarbon phthalocyanine hydrazine method. The elemental constitution in the precipitate was detected by EDS. The Kruskal-Wallis test was used to analyze surface mineralization and different plugging rates of dentinal tubules. The absorption capacity of dentifrices were also evaluated by the Kruskal-Wallis test. Results: The plugging rate in the HA dentifrice group was higher than that in the ordinary dentifrice group, and the 80 nm HA dentifrice group showed the best result. The atomic percentages of Ca and P of 80 nm dentifrice group on the surface of dentinal tubules were the highest. The 80 nm HA dentifrice group showed the best adsorption and stable effect of Cr6+, followed by the 300 nm HA dentifrice group. The 300 nm HA dentifrice and the ordinary dentifrice showed desorption phenomenon. Conclusions: The dentifrice containing HA, especially the 80 nm HA dentifrice, exerts good dentinal tubule occlusion and surface mineralization effect. This dentifrice was also a good adsorbent of Cr6+.


Assuntos
Cromo/isolamento & purificação , Dentifrícios/farmacologia , Dentina/efeitos dos fármacos , Durapatita/farmacologia , Tamanho da Partícula , Adsorção , Cálcio/análise , Humanos , Fósforo/análise , Espectrometria por Raios X , Água
18.
Int J Nanomedicine ; 14: 5799-5816, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31440048

RESUMO

Purpose: Bone consolidation after severe trauma is the most challenging task in orthopedic surgery. This study aimed to develop biomimetic composite for coating Ti implants. Afterwards, these implants were tested in vivo to assess bone consolidation in the absence or the presence of high-frequency pulsed electromagnetic short-waves (HF-PESW). Materials: Biomimetic coating was successfully developed using multi-substituted hydroxyapatite (ms-HAP) functionalized with collagen (ms-HAP/COL), embedded into poly-lactic acid (PLA) matrix (ms-HAP/COL@PLA), and subsequently covered with self-assembled COL layer (ms-HAP/COL@PLA/COL, named HAPc). Methods: For in vivo evaluation, 32 Wistar albino rats were used in four groups: control group (CG) with Ti implant; PESW group with Ti implant+HF-PESW; HAPc group with Ti implant coated with HAPc; HAPc+PESW group with Ti implant coated with HAPc+HF-PESW. Left femoral diaphysis was fractured and fixed intramedullary. From the first post-operative day, PESW and HAPc+PESW groups underwent HF-PESW stimulation for 14 consecutive days. Biomimetic coating was characterized by XRD, HR-TEM, SEM, EDX and AFM. Results: Osteogenic markers (ALP and osteocalcin) and micro-computed tomography (CT) analysis (especially bone volume/tissue volume ratio results) indicated at 2 weeks the following group order: HAPc+PESW>HAPc≈PESW (P>0.05) and HAPc+PESW>control (P<0.05), indicating the higher values in HAPc+PESW group compared to CG. The fracture-site bone strength showed, at 2 weeks, the highest average value in HAPc+PESW group. Moreover, histological analysis revealed the most abundant COL fibers assembled in dense bundles in HAPc-PESW group. At 8 weeks, micro-CT indicated higher values only in HAPc+PESW group vs CG (P<0.05), and histological results showed a complete-healed fracture in groups: HAPc+PESW, HAPc and PESW, but with more advanced bone remodeling in HAPc+PESW group. Conclusion: Using Ti implants coated by HAPc jointly with HF-PESW stimulation positively influenced the bone consolidation process, especially in its early phase, thus potentially providing a superior strategy for clinical applications.


Assuntos
Materiais Biomiméticos/farmacologia , Osso e Ossos/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Fenômenos Eletromagnéticos , Poliésteres/química , Próteses e Implantes , Titânio/farmacologia , Animais , Biomarcadores/sangue , Fenômenos Biomecânicos , Bovinos , Colágeno/farmacologia , Durapatita/farmacologia , Fêmur/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Ratos Wistar , Propriedades de Superfície , Microtomografia por Raio-X
19.
Int J Nanomedicine ; 14: 6151-6163, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447557

RESUMO

Background: Precise control and induction of the differentiation of stem cells to osteoblasts by artificial biomaterials are a promising strategy for rapid bone regeneration and reconstruction. Purpose: In this study, gold nanoparticles (AuNPs)-loaded hydroxyapatite (HA-Au) nanocomposites were designed to guide the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hMSCs) through the synergistic effects of both AuNPs and HA. Materials and methods: The HA-Au nanoparticles were synthesized and characterized by several analytical techniques. Cell viability and proliferation of hMSCs were characterized by CCK-8 test. Cellular uptake of nanoparticles was observed by transmission electron microscope. For the evaluation of osteogenic differentiation, alkaline phosphatase (ALP) activity and staining, Alizarin red staining, and a quantitative real-time polymerase chain reaction (RT-PCR) analysis were performed. In order to examine specific signaling pathways, RT-PCR and Western blotting assay were performed. Results: The results confirmed the successful synthesis of HA-Au nanocomposites. The HA-Au nanoparticles showed good cytocompatibility and internalized into hMSCs at the studied concentrations. The increased level of ALP production, deposition of calcium mineralization, as well as the expression of typical osteogenic genes, indicated the enhancement of osteogenic differentiation of hMSCs. Moreover, the incorporation of Au could activate the Wnt/ß-catenin signaling pathway, which seemed to be the molecular mechanism underlying the osteoinductive capability of HA-Au nanoparticles. Conclusion: The HA-Au nanoparticles exerted a synergistic effect on accelerating osteogenic differentiation of hMSCs, suggesting they may be potential candidates for bone repair and regeneration.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Durapatita/farmacologia , Ouro/química , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Nanopartículas Metálicas/química , Osteogênese , Via de Sinalização Wnt/efeitos dos fármacos , Fosfatase Alcalina/metabolismo , Cálcio/metabolismo , Diferenciação Celular/genética , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/enzimologia , Nanopartículas Metálicas/ultraestrutura , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Osteogênese/genética
20.
J Mater Sci Mater Med ; 30(9): 99, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455977

RESUMO

Adipose-derived mesenchymal stem cells (ASCs) accelerate the osteointegration of bone grafts and improve the efficiency in the formation of uniform bone tissue, providing a practical and clinically attractive approach in bone tissue regeneration. In this work, the effect of nanofibrous biomimetic matrices composed of poly(ε-caprolactone) (PCL), nanometric hydroxyapatite (nHA) particles and 14-3-3 protein isoform epsilon on the initial stages of human ASCs (hASCs) osteogenic differentiation was investigated. The cells were characterized by flow cytometry and induction to differentiation to adipogenic and osteogenic lineages. The isolated hASCs were induced to differentiate to osteoblasts over all scaffolds, and adhesion and viability of the hASCs were found to be similar. However, the activity of alkaline phosphatase (ALP) as early osteogenic marker in the PCL-nHA/protein scaffold was four times higher than in PCL-nHA and more than five times than the measured in neat PCL.


Assuntos
Proteínas 14-3-3 , Durapatita , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poliésteres , Tecidos Suporte/química , Proteínas 14-3-3/química , Proteínas 14-3-3/farmacologia , Diferenciação Celular/efeitos dos fármacos , Diferenciação Celular/fisiologia , Células Cultivadas , Durapatita/química , Durapatita/farmacologia , Galvanoplastia/métodos , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Nanofibras/química , Osteoblastos/efeitos dos fármacos , Osteoblastos/fisiologia , Osteogênese/fisiologia , Poliésteres/química , Poliésteres/farmacologia , Gordura Subcutânea Abdominal/citologia , Propriedades de Superfície/efeitos dos fármacos , Engenharia Tecidual/métodos
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