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1.
J Med Life ; 13(3): 418-425, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072218

RESUMO

The study aimed to investigate whether a 3D printed beta-tricalcium phosphate (ß-TCP) scaffold tethered with growth factors and fibrin glue implanted autologous bone marrow-derived mesenchymal stem cells would provide a 3D platform for bone regeneration resulting in new bone formation with plasticity. Twenty 3D printed ß-TCP scaffolds, ten scaffolds engrained with osteogenic mesenchymal stem cells with fibrin glue (group A), and ten scaffolds used as a control group with ß-TCP scaffold and fibrin glue inoculation only (group B) were included in the study. Cell infiltration, migration, and proliferation of human osteogenic stem cells on the scaffolds were executed under both static and dynamic culture conditions. Each scaffold was examined post culture after repeated changes in the nutrient medium at 2, 4 or 8 weeks and assessed for opacity and formation of any bone-like tissues macroscopic, radiographic, and microscopic evaluation. Significant changes in all the prerequisite parameters compiled with an evaluated difference of significance showing maxillofacial skeletal repair via tissue engineering by ß-TCP scaffold and MSCs remains will be the most promising alternative to autologous bone grafts and numerous modalities involving a variety of stem cells, growth factors from platelet-rich fibrin.


Assuntos
Fosfatos de Cálcio/farmacologia , Adesivo Tecidual de Fibrina/farmacologia , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Anormalidades Maxilofaciais/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Impressão Tridimensional , Engenharia Tecidual/métodos , Estudos de Casos e Controles , Sobrevivência Celular/efeitos dos fármacos , Humanos , Anormalidades Maxilofaciais/diagnóstico por imagem , Anormalidades Maxilofaciais/patologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Minerais/análise , Tecidos Suporte/química , Resultado do Tratamento
2.
J Dent ; 97: 103344, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32315666

RESUMO

OBJECTIVES: Senior patients have a high incidence of tooth root caries. The objectives of this study were to: (1) develop a bioactive composite with calcium (Ca) and phosphate (P) ion-release and antibacterial capabilities via nanoparticles of amorphous calcium phosphate (NACP) and dimethylaminohexadecyl methacrylate (DMAHDM); (2) inhibit root biofilms of Streptococcus mutans, Lactobacillus acidophilus and Candida albicans in a biofilm-based recurrent root caries model to protect root dentin hardness under biofilms for the first time. METHODS: Five groups were tested: (1) Heliomolar nanocomposite (Commercial control); (2) Experimental composite control (0% NACP, 0% DMAHDM); (3) Remineralizing composite (30% NACP); (4) Antibacterial composite (3% DMAHDM); (5) Remineralizing and antibacterial composite (NACP + DMAHDM). Colony-forming units (CFU), lactic acid and polysaccharide of biofilms were evaluated. Demineralization of bovine root dentin with restorations was induced via multi-species biofilms, and root dentin hardness was measured. RESULTS: Adding NACP and DMAHDM into composite did not compromise the mechanical properties (p >  0.05). Biofilm lactic acid, polysaccharides and CFU were greatly reduced via DMAHDM (p < 0.05). Ca and P ion releases were substantially increased at cariogenic low pH. With multi-species biofilm acid attack, root dentin hardness (GPa) decreased to 0.12 ± 0.03 for Commercial control, and 0.11 ± 0.03 for Experimental control. Root dentin hardness was 0.20 ± 0.04 for NACP group, 0.21 ± 0.04 for DMAHDM group, and 0.30 ± 0.03 for NACP + DMAHDM group which was more than 2-fold that of control groups (p < 0.05). CONCLUSIONS: The novel NACP + DMAHDM nanocomposite had strong antibacterial effects and Ca and P ion release. When tested in a multi-species recurrent root caries model, NACP + DMAHDM nanocomposite substantially reduced root dentin demineralization and protected dentin hardness around the restorations under biofilms. Therefore, this novel bioactive composite is promising to inhibit root caries and protect tooth structures.


Assuntos
Nanocompostos , Cárie Radicular , Animais , Antibacterianos/farmacologia , Biofilmes , Fosfatos de Cálcio/farmacologia , Bovinos , Dentina , Dureza , Humanos , Metacrilatos/farmacologia , Cárie Radicular/prevenção & controle
3.
Curr Med Sci ; 40(1): 155-167, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32166678

RESUMO

Bone and teeth are derived from intrafibrillarly mineralized collagen fibrils as the second level of hierarchy. According to polymer-induced liquid-precursor process, using amorphous calcium phosphate precursor (ACP) is able to achieve intrafibrillar mineralization in the case of bone biomineral in vitro. Therefore, ACP precursors might be blended with any osteoconductive scaffold as a promising bone formation supplement for in-situ remineralization of collagens in bone. In this study, mesoporous silica nanoparticles with carboxyl-functionalized groups and ultra large-pores have been synthesized and used for the delivery of liquid like biomimetic precursors (ACP). The precursor delivery capacity of the nanoparticles was verified by the precursor release profile and successful mineralization of 2D and 3D collagen models. The nanoparticles could be completely degraded in 60 days and exhibited good biocompatibility as well. The successful translational strategy for biomineralization precursors showed that biomineralization precursor laden ultra large pore mesoporous silica possessed the potential as a versatile supplement in demineralized bone formation through the induction of intrafibrillar collagen mineralization.


Assuntos
Fosfatos de Cálcio/farmacologia , Colágeno/química , Células-Tronco Mesenquimais/citologia , Dióxido de Silício/química , Animais , Biomineralização/efeitos dos fármacos , Fosfatos de Cálcio/química , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Colágeno/efeitos dos fármacos , Feminino , Células-Tronco Mesenquimais/química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas , Porosidade , Ratos
4.
BMC Biotechnol ; 20(1): 8, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005149

RESUMO

BACKGROUND: The translation from animal research into the clinical environment remains problematic, as animal systems do not adequately replicate the human in vivo environment. Bioreactors have emerged as a good alternative that can reproduce part of the human in vivo processes at an in vitro level. However, in vitro bone formation platforms primarily utilize stem cells only, with tissue based in vitro systems remaining poorly investigated. As such, the present pilot study explored the tissue behavior and cell survival capability within a new in vitro skeletal muscle tissue-based biomaterial organoid bioreactor system to maximize future bone tissue engineering prospects. RESULTS: Three dimensional printed ß-tricalcium phosphate/hydroxyapatite devices were either wrapped in a sheet of rat muscle tissue or first implanted in a heterotopic muscle pouch that was then excised and cultured in vitro for up to 30 days. Devices wrapped in muscle tissue showed cell death by day 15. Contrarily, devices in muscle pouches showed angiogenic and limited osteogenic gene expression tendencies with consistent TGF-ß1, COL4A1, VEGF-A, RUNX-2, and BMP-2 up-regulation, respectively. Histologically, muscle tissue degradation and fibrin release was seen being absorbed by devices acting possibly as a support for new tissue formation in the bioceramic scaffold that supports progenitor stem cell osteogenic differentiation. CONCLUSIONS: These results therefore demonstrate that the skeletal muscle pouch-based biomaterial culturing system can support tissue survival over a prolonged culture period and represents a novel organoid tissue model that with further adjustments could generate bone tissue for direct clinical transplantations.


Assuntos
Materiais Biocompatíveis/farmacologia , Músculo Esquelético/citologia , Organoides/citologia , Osteogênese , Células-Tronco/citologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/química , Biomarcadores/metabolismo , Reatores Biológicos , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Durapatita/química , Durapatita/farmacologia , Músculo Esquelético/metabolismo , Projetos Piloto , Impressão Tridimensional , Estudo de Prova de Conceito , Ratos , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Tecidos Suporte , Sobrevivência de Tecidos
5.
Medicina (Kaunas) ; 56(2)2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31972958

RESUMO

Background and Objectives: Maxillary bone defects related to post-extraction alveolar ridge resorption are usual. These defects may lead to failure in further surgical implant phases given the lack of bone volume to perform the dental implant. The objective of this clinical assay was to evaluate the safety and efficacy of an experimental synthetic bone substitute in the preservation of post-extraction maxillary alveoli. Materials and Methods: 33 voluntary patients who had at least one maxillary premolar tooth that was a candidate for exodontia (n = 39) and subsequent implant rehabilitation participated. The regenerated alveoli were monitored by means of periodic clinical examinations (days 9 ± 1, 21 ± 4, 42 ± 6, and 84 ± 6), measuring the height and width of the alveolar crest (days 0 and 180 ± 5), measurement of radiodensity using tomographic techniques (days 0-5 and 175 ± 5), and histological examination of biopsies collected at 180 ± 5 days. Results: No significant differences were observed during the entire follow-up period between the two groups with respect to the safety variables studied. A variation in width of -0.9 ± 1.3 mm and -0.6 ± 1.5 mm, and a variation in height of -0.1 ± 0.9 mm and -0.3 ± 0.7 mm was observed for experimental material Sil-Oss® and Bio-Oss®, respectively. The radiodensity of the alveoli regenerated with the experimental material was significantly lower than that corresponding to Bio-Oss®. However, the histological study showed greater osteoid matrix and replacement of the material with newformed bone in the implanted beds with the experimental material. Conclusions: Both materials can be used safely and proved equally effective in maintaining alveolar flange dimensions, they are also histologically biocompatible, bioactive and osteoconductive. The experimental material showed the advantage of being resorbable and replaced with newformed bone, in addition to promoting bone regeneration.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Fosfatos de Cálcio/farmacologia , Durapatita/antagonistas & inibidores , Sílica Gel/farmacologia , Adulto , Perda do Osso Alveolar/prevenção & controle , Substitutos Ósseos/normas , Substitutos Ósseos/uso terapêutico , Fosfatos de Cálcio/uso terapêutico , Método Duplo-Cego , Combinação de Medicamentos , Durapatita/farmacologia , Durapatita/uso terapêutico , Feminino , Humanos , Masculino , Maxila/efeitos dos fármacos , Maxila/fisiopatologia , Pessoa de Meia-Idade , Sílica Gel/uso terapêutico
6.
Carbohydr Polym ; 229: 115472, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31826419

RESUMO

TEMPO oxidized cellulose nanofibers (T-CNF) were prepared from cellulose pulp which is extracted from bagasse. Soy protein hydrolysate (SPH) was grafted on T-CNF via amidation of carboxylic groups. Biomineralization was, then, assessed via calcium phosphates (CaP) precipitation in twice-simulated body fluid until formation of a new bioactive material. Protein was efficiently grafted without alteration of morphology and nanofibrils packing as reported by Fourier Transform infrared analysis /X Ray Diffraction /Scanning and Transmission Electron Microscopy / Atomic Force Microscopy. Highly crystalline calcium phosphate deposits - ca. 22.1% - were detected, with a Ca/P ratio equal to 1.63, in agreement with native bone apatite composition. In vitro response of human Mesenchymal Stem Cells confirmed the biocompatibility. No significant differences in terms of cell adhesion were recognized while a significant increase in cell proliferation was detected until 7 days. The presence of calcium phosphates tends to cover the nanofibrillar pattern, inducing the inhibition of cell proliferation and promoting the ex-novo precipitation of mineral phases. All the results suggest a promising use of these biomaterials in the repair and/or the regeneration of hard tissues such as bone.


Assuntos
Materiais Biocompatíveis/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Celulose/farmacologia , Nanofibras/química , Hidrolisados de Proteína/farmacologia , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/toxicidade , Fosfatos de Cálcio/síntese química , Fosfatos de Cálcio/farmacologia , Fosfatos de Cálcio/toxicidade , Proliferação de Células/efeitos dos fármacos , Celulose/análogos & derivados , Celulose/toxicidade , Óxidos N-Cíclicos/química , Géis/síntese química , Géis/farmacologia , Géis/toxicidade , Humanos , Nanocompostos/química , Nanocompostos/toxicidade , Nanofibras/toxicidade , Oxirredução , Hidrolisados de Proteína/química , Hidrolisados de Proteína/toxicidade , Soja/química
7.
Chemosphere ; 245: 125611, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31864057

RESUMO

Lead-contaminated soils are becoming an ecological risk to the environment because of producing low-quality food which is directly causing critical health issues in humans and animals. We hypothesized that incorporation of dicalcium phosphate (DCP), eggshell powder (ESP) and biochar (BH) at diverse rates into a Pb-affected soil can proficiently immobilize Pb and decline its bioavailability to spinach (Spinacia oleracea L.). A soil was artificially spiked with Pb concentration (at 600 mg kg-1) and further amended with DCP, ESP, and BH (as sole treatments at 2% and in concoctions at 1% each) for immobilization of Pb in the soil. The interlinked effects of applied treatments on Pb concentrations in shoots and roots, biomass, antioxidants, biochemistry, and nutrition of spinach were also investigated. Results depicted that the highest reduction in DTPA-extractable Pb and the concentrations of Pb in shoots and roots was achieved in DCP1%+BH1% treatment that was up to 58%, 66%, and 53%, respectively over control. Likewise, the DCP1%+BH1% treatment also showed the maximum shoot and root dry weight (DW), chlorophyll-a (Chl-a) and chlorophyll-b (Chl-b) contents and relative water content (RWC) in spinach up to 92%, 121%, 60%, 65%, and 30%, respectively, compared to control. Likewise, DCP1%+BH1% treatment noticeably improved antioxidant enzymes, biochemistry, and nutrition in the leaves. Moreover, the DCP1%+BH1% treatment depicted mostly enhanced activities of dehydrogenase, catalase, acid phosphatase, alkaline phosphatase, phosphomonoesterase, urease, protease and B-glucosidase in the post-harvested soil up to 118%, 345%, 55%, 92%, 288%, 107%, 53% and 252%, respectively over control.


Assuntos
Fosfatos de Cálcio/química , Carvão Vegetal/química , Chumbo/isolamento & purificação , Pistacia/química , Solo/química , Spinacia oleracea/metabolismo , Antioxidantes/metabolismo , Disponibilidade Biológica , Fosfatos de Cálcio/farmacologia , Carvão Vegetal/farmacologia , Enzimas/efeitos dos fármacos , Valor Nutritivo , Folhas de Planta/metabolismo , Poluentes do Solo/análise
8.
Int J Mol Sci ; 20(24)2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31835689

RESUMO

There is a current clinical need for the development of bone void fillers and bioactive bone graft substitutes. The use of mesenchymal stem cells (MSCs) that are seeded into 3D scaffolds and induce bone generation in the event of MSCs osteogenic differentiation is highly promising. Since calcium ions and phosphates promote the osteogenic differentiation of MSCs, the use of the calcium complexes of phosphate-containing polymers is highly prospective in the development of osteogenic scaffolds. Calcium poly(ethylene phosphate)s (PEP-Ca) appear to be potentially suitable candidates primarily because of PEP's biodegradability. In a series of experiments with human adipose-tissue-derived multipotent mesenchymal stem cells (ADSCs), we demonstrated that PEP-Ca are non-toxic and give rise to osteogenesis gene marker, bone morphogenetic protein 2 (BMP-2) and mineralization of the intercellular matrix. Owing to the synthetic availability of poly(ethylene phosphoric acid) block copolymers, these results hold out the possibility for the development of promising new polymer composites for orthopaedic and maxillofacial surgery.


Assuntos
Fosfatos de Cálcio/farmacologia , Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Osteogênese/efeitos dos fármacos , Polietileno/farmacologia , Calcificação Fisiológica/efeitos dos fármacos , Cálcio/química , Fosfatos de Cálcio/química , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Humanos , Células-Tronco Multipotentes/citologia , Células-Tronco Multipotentes/efeitos dos fármacos , Ácidos Fosfóricos/síntese química , Ácidos Fosfóricos/química , Polietileno/química
9.
Int J Mol Sci ; 20(22)2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31731607

RESUMO

Calcium phosphate bions (CPBs) are formed under blood supersaturation with calcium and phosphate owing to the mineral chaperone fetuin-A and representing mineralo-organic particles consisting of bioapatite and multiple serum proteins. While protecting the arteries from a rapid medial calcification, CPBs cause endothelial injury and aggravate intimal hyperplasia in balloon-injured rat aortas. Here, we asked whether CPBs induce intimal hyperplasia in intact rat arteries in the absence of cardiovascular risk factors. Normolipidemic Wistar rats were subjected to regular (once/thrice per week over 5 weeks) tail vein injections of either spherical (CPB-S) or needle-shaped CPBs (CPB-N), magnesium phosphate bions (MPBs), or physiological saline (n = 5 per group). Neointima was revealed in 3/10 and 4/10 rats which received CPB-S or CPB-N, respectively, regardless of the injection regimen or blood flow pattern in the aortic segments. In contrast, none of the rats treated with MPBs or physiological saline had intimal hyperplasia. The animals also did not display signs of liver or spleen injury as well as extraskeletal calcium deposits. Serum alanine/aspartate transaminases, interleukin-1ß, MCP-1/CCL2, C-reactive protein, and ceruloplasmin levels did not differ among the groups. Hence, CPBs may provoke intimal hyperplasia via direct endothelial injury regardless of their shape or type of blood flow.


Assuntos
Aorta/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Doenças Cardiovasculares/sangue , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Durapatita/química , Masculino , Neointima/sangue , Ratos , Ratos Wistar , Fatores de Risco
10.
Bull Exp Biol Med ; 167(5): 681-684, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31630302

RESUMO

The effects of bone graft materials on the inflammatory response and biochemical markers of bone remodeling were studied on a rabbit model of fracture augmentation with the following grafts: ß-tricalcium phosphate, demineralized bone matrix, nanostructured carbon implant, and porous titanium implant made by additive 3D printing. The markers of bone remodeling and the blood system response in the postoperative period were studied. It was found that porous titanium implant and ß-tricalcium phosphate induced osteogenesis and minimized osteoclastic resorption. Augmentation with nanostructured carbon implant and demineralized bone matrix stimulated the processes of osteoclastic resorption.


Assuntos
Materiais Biocompatíveis/farmacologia , Transplante Ósseo/métodos , Fosfatos de Cálcio/farmacologia , Cementoplastia/métodos , Fraturas Intra-Articulares/terapia , Osseointegração/efeitos dos fármacos , Titânio/farmacologia , Fosfatase Alcalina/sangue , Fosfatase Alcalina/genética , Animais , Biomarcadores/metabolismo , Técnica de Desmineralização Óssea , Matriz Óssea/química , Remodelação Óssea , Reabsorção Óssea/metabolismo , Carbono/metabolismo , Carbono/farmacologia , Colágeno Tipo I/sangue , Colágeno Tipo I/genética , Feminino , Fraturas Intra-Articulares/metabolismo , Fraturas Intra-Articulares/cirurgia , Nanoestruturas/química , Osseointegração/fisiologia , Osteocalcina/sangue , Osteocalcina/genética , Peptídeos/sangue , Peptídeos/genética , Porosidade , Coelhos , Tíbia/efeitos dos fármacos , Tíbia/lesões , Tíbia/metabolismo , Tíbia/cirurgia
11.
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
12.
J Appl Biomater Funct Mater ; 17(2): 2280800019857064, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31597509

RESUMO

BACKGROUND: Rapid corrosion rates are a major impediment to the use of magnesium alloys in bone tissue engineering despite their good mechanical properties and biodegradability. Zinc is a promising alloy element, and it is an effective grain refiner for magnesium. ß-Ca3(PO4)2 (ß-TCP) is widely used for bone regeneration because of its good biocompatibility, and it also has a similar chemical and crystal structure to human bone. METHODS: In this research, the magnesium alloy was reinforced by adding 3%Zn (wt.%) and 5%ß-TCP (wt.%) particles in order to improve the corrosion resistance and biocompatibility. Furthermore, the biomaterial was prepared through powder metallurgy technology using NH4HCO3 as space-holding particles to construct porous Mg-3%Zn/5%ß-TCP scaffolds. RESULTS: The results revealed that the magnesium-zinc phase and calcium phosphate phase were uniformly distributed in the α-magnesium matrix. Mechanical and corrosion tests indicated that the scaffolds had mechanical strengths similar to that of human bone, and their corrosion resistance decreased with an increase in the porosity. The scaffolds had cytotoxicity grades of 0-1 against MG63 cells, SaoS2 cells, and HK-2 cells, which suggested that they were appropriate for cellular applications. In addition, the scaffolds demonstrated excellent biocompatibility when tested in rabbits. CONCLUSIONS: These results indicate that porous Mg-3%Zn/5%ß-TCP scaffolds are promising biodegradable implants for bone tissue engineering.


Assuntos
Implantes Absorvíveis , Ligas , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio , Magnésio , Tecidos Suporte/química , Zinco , Ligas/química , Ligas/farmacologia , Animais , Osso e Ossos/metabolismo , Osso e Ossos/patologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Linhagem Celular Tumoral , Corrosão , Humanos , Magnésio/química , Magnésio/farmacologia , Porosidade , Coelhos , Engenharia Tecidual , Zinco/química , Zinco/farmacologia
13.
PLoS One ; 14(9): e0222034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31536540

RESUMO

OBJECTIVE: Local antibiotic delivery systems with differing chemical and mechanical properties have been developed to assist in the management of osteomyelitis. We investigated the bone conductive and resorptive capabilities of a calcium phosphate-calcium sulfate (CaP/CaS) composite compared with commercially available polymethylmethacrylate (PMMA). In addition, we compared the in vivo preventative and treatment efficacies of both biomaterials in a proven osteomyelitis model. METHODS: Sixty-four, male Sprague-Dawley rats were inoculated with 10 µl of 1.5 x 108 CFU/ml of Staphylococcus aureus in a surgically drilled defect in the right proximal tibia. Infected animals were randomly allocated into prevention and treatment groups with 32 rats each. In the prevention group, the defect was filled with a plug containing either PMMA or CaP/CaS immediately after the inoculation. In the treatment group, the infected defects were irrigated, debrided, and filled with either a PMMA or CaP/CaS plug. Both CaP/CaS and PMMA were impregnated with 10% weight of vancomycin. Rats were sacrificed 6 weeks after cement insertion. Infection was detected by bacterial culture and histological analysis. Bone formation in the defect was assessed with micro-computed tomography and histology. RESULTS: No bacteria were detected in any group. Both the prevention and treatment groups using CaP/CaS had significantly more bone volume fraction, bone area, and cartilage area than the PMMA groups. CONCLUSIONS: When loaded with 10% of vancomycin, CaP/CaS and PMMA have the same efficacy for treatment and prevention of osteomyelitis. CaP/CaS enhances bone defect healing through improved bone remodeling in our osteomyelitis rat model.


Assuntos
Fosfatos de Cálcio/administração & dosagem , Sulfato de Cálcio/administração & dosagem , Osteomielite/tratamento farmacológico , Polimetil Metacrilato/administração & dosagem , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina/administração & dosagem , Animais , Materiais Biocompatíveis/administração & dosagem , Materiais Biocompatíveis/farmacologia , Fosfatos de Cálcio/farmacologia , Sulfato de Cálcio/farmacologia , Modelos Animais de Doenças , Humanos , Masculino , Osteogênese/efeitos dos fármacos , Osteomielite/diagnóstico por imagem , Osteomielite/microbiologia , Osteomielite/prevenção & controle , Polimetil Metacrilato/farmacologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Infecções Estafilocócicas/complicações , Infecções Estafilocócicas/diagnóstico por imagem , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Resultado do Tratamento , Vancomicina/química , Vancomicina/farmacologia , Microtomografia por Raio-X
14.
Mater Sci Eng C Mater Biol Appl ; 105: 110027, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546388

RESUMO

The application of heat stress on a defect site during the healing process is a promising technique for early bone regeneration. The primary goal of this study was to investigate the effect of periodic heat shock on bone formation. MC3T3-E1 cells were seeded onto biphasic calcium phosphate (BCP) scaffolds, followed by periodic heating to evaluate osteogenic differentiation. Heat was applied to cells seeded onto scaffolds at 41 °C for 1 h once, twice, and four times a day for seven days and their viability, morphology, and differentiation were analyzed. BCP scaffolds with interconnected porous structures mimic bone biology for cellular studies. MTT and confocal studies have shown that heat shock significantly increased cell proliferation without any toxic effects. Compared to non-heated samples, heat shock enhanced calcium deposition and mineralization, which could be visualized by SEM observation and Alizarin red S staining. Immunostaining images showed the localization of osteogenic proteins ALP and OPN on heat-shocked cells. qRT-PCR analysis revealed the presence of more osteospecific markers, osteopontin (OPN), osteocalcin, collagen type X, and Runx2, in the heat-shocked samples than in the non-heated sample. Periodic heat shock significantly upregulated both heat shock proteins (HSP70 and HSP27) in differentiated MC3T3-E1 cells. The results of this study demonstrated that periodically heat applied especially two times a day was better approach for osteogenic differentiation. Hence, this work provides a define temperature and time schedule for the development of a clinical heating device in future for early bone regeneration during the postsurgical period.


Assuntos
Fosfatos de Cálcio/farmacologia , Diferenciação Celular , Osteogênese , Temperatura , Fosfatase Alcalina/metabolismo , Animais , Biomarcadores , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Minerais/metabolismo , Modelos Biológicos , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Porosidade , Fatores de Tempo , Tecidos Suporte/química
15.
Mater Sci Eng C Mater Biol Appl ; 105: 110014, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546414

RESUMO

Cuttlefish bone (CB) has been explored as biomaterial in the bone tissue-engineering field due to its unique porous structure and capacity of the aragonite mineral to be hydrothermally converted into calcium phosphates (CaPs). In the present study, undoped and ion (Sr2+, Mg2+ and/or Zn2+) doped biphasic calcium phosphate (BCP) scaffolds were prepared by hydrothermal transformation (HT, 200 °C, 24 h) of CB. The obtained scaffolds were sintered and then coated with two commercial polymers, poly(ε-caprolactone) (PCL) or poly(DL-lactide) (PDLA), and with two synthesized ones, a poly(ester amide) (PEA) or a poly(ester urea) (PEU) in order to improve their compressive strength. The scaffolds were characterized by X-ray diffraction (XRD) coupled with structural Rietveld refinement, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The results demonstrate that CB could be entirely transformed into BCPs in the presence or absence of doping elements. The initial CB structure was preserved and the polymeric coatings did not jeopardize the interconnected porous structure. Furthermore, the polymeric coatings enhanced the compressive strength of the scaffolds. The in vitro bio-mineralization upon immersing the scaffolds into simulated body fluid (SBF) demonstrated the formation of bone-like apatite surface layers in both uncoated and coated scaffolds. Overall, the produced scaffolds exhibit promising properties for bone tissue engineering applications.


Assuntos
Osso e Ossos/química , Fosfatos de Cálcio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Decapodiformes/anatomia & histologia , Polímeros/farmacologia , Tecidos Suporte/química , Animais , Osso e Ossos/ultraestrutura , Calcificação Fisiológica , Força Compressiva , Módulo de Elasticidade , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície , Temperatura , Difração de Raios X
16.
Mater Sci Eng C Mater Biol Appl ; 105: 110065, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546449

RESUMO

In order to investigate the influence of Zn on the hydration reaction of calcium phosphate cement (CPC), the incompletely hydrated CPC tablets were kept soaking in varying zinc-containing tris-(hydroxymethyl)-aminomethane/hydrochloric acid (Zn-Tris-HCl) buffers. It was found that Zn could retard the CPC hydration, the inhibitory effect was in direct proportional to the Zn content in the Zn-Tris-HCl buffer, and overhigh concentration of Zn (≧800 µM) caused the CPC hydration products having different phase composition and surface morphology. Cell culture experimental results revealed the CPC tablets which were soaked in the Zn-Tris-HCl buffer containing relative low Zn content (≦320 µM) favored the mouse bone mesenchymal stem cells (mBMSCs) spreading. When Zn-doped CPC tablets released 10.91 to 27.15 µM of zinc ions into the cell culture medium, it greatly contributed to the improvement of the proliferation ability and the alkaline phosphatase (ALP) activity of the mBMSCs. In the same case, the expression of osteogenesis related genes such as collagen I and runt-related transcription factor 2 was remarkably up-regulated as well. However, the release of high concentration of Zn (128.58 µM) would significantly reduce the ALP activity of the mBMSCs. Therefore, Zn not only facilitates osteogenesis but also affects the CPC hydration behavior, and the CPC with suitable Zn dosage concentration has great potentials to be used for clinical bone repairing.


Assuntos
Cimentos para Ossos , Células da Medula Óssea/metabolismo , Fosfatos de Cálcio , Células-Tronco Mesenquimais/metabolismo , Osteogênese/efeitos dos fármacos , Zinco , Animais , Cimentos para Ossos/química , Cimentos para Ossos/farmacologia , Células da Medula Óssea/citologia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Camundongos , Zinco/química , Zinco/farmacologia
17.
Mater Sci Eng C Mater Biol Appl ; 105: 109879, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546456

RESUMO

In this study, a porous Ti-alloy based implant with an interconnected channel structure (MAO-CaP-BMP2) is fabricated using a method combining 3D printing, microarc oxidation (MAO) treatment, and co-precipitation of Ca,P layer with BMP-2 technique. The macroporous structure with pore size of 600 µm made by 3D printing not only enhances the ingrowth of cells but also allows the formation of blood vessels inside the implant. As a result, the new bond formation is promoted. In addition, the microporous dioxide layer formed on the implant surface by MAO provides the sites for co-precipitation of Ca,P layer with BMP-2. The microstructure allows the prolonged release of BMP-2. Our results show that a sustained release of BMP-2 over 35 days is achieved for MAO-CaP-BMP2 group longer than Ti without MAO modification group and without Ca,P electrochemical deposition group. The slow release of BMP-2 at the bone/implant interface for a long period of time leads to enhancement of the osseointegration between the implant and surrounding bones. This result indicates that MAO-CaP-BMP2 is a good candidate of growth factor carrier. Successful regeneration of bone requires the concomitant processes of osteogenesis and neovascularization. MAO-CaP-BMP2 modified Ti-alloy implant is both osteoinductive and osteoconductive which can create better osteogenesis and angiogenesis. As a result, it can enhance bone formation.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Galvanoplastia , Osteogênese/efeitos dos fármacos , Titânio/química , Fator de Crescimento Transformador beta/farmacologia , Ligas/farmacologia , Animais , Fosfatos de Cálcio/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Preparações de Ação Retardada/farmacologia , Liberação Controlada de Fármacos , Humanos , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Oxirredução , Próteses e Implantes , Coelhos , Proteínas Recombinantes/farmacologia , Crânio/efeitos dos fármacos , Crânio/patologia
18.
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
19.
Mater Sci Eng C Mater Biol Appl ; 105: 110096, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546344

RESUMO

The objective of this study is to understand the effect of sustained release of vitamin C from ß-tricalcium phosphate (ß-TCP) scaffold on proliferation, viability and differentiation of human fetal osteoblast cells (hFOB). The influence of pH, drug concentration, and presence of polymer on the sustained release of vitamin C from polycaprolactone (PCL) coated ß-TCP scaffolds are studied. Prolonged and sustained release of vitamin C, over 60 days is observed in PCL coated ß-TCP scaffolds compared to uncoated scaffolds. Presence of PCL helps to minimize the burst release of vitamin C from ß-TCP scaffolds in the initial 24 h of release. To evaluate the osteogenic potential of vitamin C incorporated ß-TCP scaffolds, osteoblast cells are cultured and cell morphology, proliferation, viability, and differentiation are assessed. Morphological characterization shows layer like osteoblast cell attachment in the presence of vitamin C compared to the control. MTT cell viability assay shows 2 folds increase in osteoblast cell density in the presence of vitamin C after 3,7 and 11 days of culture. Furthermore, increased ALP activity at 11 days of culture indicates the possible role of vitamin C on osteoblast differentiation. Additionally, a preliminary study shows vitamin C loaded scaffolds suppress osteosarcoma (MG-63) cell proliferation to 4 folds after 3 days compared to control. These results show a sustained release of vitamin C from PCL coated ß-TCP scaffolds improve proliferation, viability, and differentiation of osteoblasts cell as well as mitigate osteosarcoma cell proliferation, suggesting its potential application as synthetic bone graft substitutes in tissue engineering application.


Assuntos
Ácido Ascórbico , Neoplasias Ósseas , Fosfatos de Cálcio , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Osteoblastos/metabolismo , Osteossarcoma , Ácido Ascórbico/química , Ácido Ascórbico/farmacocinética , Ácido Ascórbico/farmacologia , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Fosfatos de Cálcio/química , Fosfatos de Cálcio/farmacocinética , Fosfatos de Cálcio/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Humanos , Osteoblastos/patologia , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , Osteossarcoma/patologia
20.
Int. j. morphol ; 37(3): 792-799, Sept. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1012355

RESUMO

The aim of the present study was to examine the short-term biocompatibility of Endosequence Root Repair Material (ERRM) paste and white Mineral Trioxide Aggregate MTA by implanting them into polyethylene tubes in the subcutaneous connective tissue of rats. twenty five male Wistar rats, 3-4 months old, weighing 300-350 g, were used. The tubes were implanted dorsally into the subcutaneous connective tissues of the rats. Five animals were sacrificed at five examination time points: 1, 3, 5, 7 and 15 days. The connective tissues containing the implants were excised. These sections were studied qualitatively and quantitatively using a light microscope. An average value for each group was obtained by averaging the sum of all inflammatory cells counted in 10 randomly selected, separate areas. For the ERRM group: There was a significant increase in the number of inflammatory cells on days 1-3 and on days 5-7 (P ≤ 0.003 and P ≤ 0.024). In the WHITE MTA group, the mean values of the sum of the inflammatory cells during the periods 1-3 days and 5-7 days were statistically significant (P ≤ 0.001 and P ≤ 0.044, respectively) and the XILOPERCHA group: Difference was observed significant in the value of the sum of inflammatory cells during the period of 3-5 days (P ≤ 0.05). According to the results it can be concluded that both, ERRM as MTA, caused an inflammatory reaction, which decreased over time; suggesting that both materials are biocompatible; showing however the presence of a higher organization of collagen fibers around the implants of ERRM.


El objetivo del presente estudio fue evaluar la biocompatibilidad a corto plazo de Material de Reparación de la Raíz Endodóntica (MRRE) y el agregado de trióxido mineral (AgTM), implantándolos dentro de tubos de polietileno en el tejido conectivo subcutáneo de ratas. Se usaron 25 ratas Wistar macho, de 3-4 meses de edad, con peso de 300 a 350 g. Los tubos fueron implantados en el tejido conectivo subcutáneo del dorso de las ratas. Cinco animales fueron sacrificados en cada uno de los siguientes períodos de tiempo: 1, 3, 5, 7, y 15 días. El tejido conectivo con los implantes fue escindido y seccionado. Los cortes se evaluaron cualitativa y cuantitativamente mediante microscopio óptico. Se obtuvo un valor para cada grupo resultado al promediar la suma de las células inflamatorias contadas en 10 áreas separadas seleccionadas aleatoriamente. Para el grupo de MRRE; hubo un incremento significativo en la cantidad de células inflamatorias entre los días 1-3 y 5-7 (p ≤ 0,003 y p ≤ 0,024). En el grupo de AgTM blanco, los valores promedio de la suma de células inflamatorias entre los períodos 1-3 días, y 5-7 días mostraron ser estadísticamente significativos (p≤ 0,001 y p ≤ 0,044 respectivamente) y en el grupo control de Xilopercha se observó diferencia significativa entre los valores de la suma de células inflamatorias entre los períodos de 3-5 días (P ≤ 0,05). De acuerdo a los resultados, puede concluirse que ambos materiales, AgTM y MRRE causaron una reacción inflamatoria que disminuyó a través del tiempo, sugiriendo que ambos materiales son biocompatibles; mostrando sin embargo una mayor organización de fibras colágenas alrededor de los implantes de MRRE.


Assuntos
Animais , Masculino , Ratos , Óxidos/farmacologia , Fosfatos de Cálcio/farmacologia , Silicatos/farmacologia , Compostos de Cálcio/farmacologia , Compostos de Alumínio/farmacologia , Tecido Conjuntivo/efeitos dos fármacos , Materiais Restauradores do Canal Radicular/farmacologia , Teste de Materiais , Ratos Wistar , Combinação de Medicamentos
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