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1.
J Appl Oral Sci ; 27: e20180602, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31508794

RESUMO

OBJECTIVE: This study aimed to evaluate the effect of avocado/soybean unsaponifiables (ASU) on periodontal repair in rats with induced periodontitis and arthritis. METHODOLOGY: Forty-five rats were submitted to periodontitis induction by insertion of ligatures into the upper second molars, maintained for 15 days. These animals were randomly allocated to 3 groups according to the presence of induced arthritis (ART) and the application of the ASU: Control (CTR) group-healthy animals, where saline solution was administered; ART-animals with induced arthritis, where saline solution was administered; ART/ASU-animals with induced arthritis, where ASU (0.6 mg/ kg) was administered. The drugs were administered daily by gavage and the animals were euthanized after 7, 15 and 30 days of the ligature removal. Bone resorption, inflammatory infiltrate composition and marker proteins expression of the differentiation and formation of osteoclasts (RANKL and TRAP) were assessed. RESULTS: The ART/ASU group presented higher bone volume than the ART group at 7 and 30 days after the ligature removal. Furthermore, the ART group presented higher quantity of inflammatory cells and expression of TRAP and RANKL than the other groups. CONCLUSION: ASU administration improves the repair of periodontal tissues in an experimental periodontitis model in rats with induced arthritis.


Assuntos
Artrite/tratamento farmacológico , Periodontite/tratamento farmacológico , Persea/química , Extratos Vegetais/farmacologia , Soja/química , Animais , Artrite/patologia , Imuno-Histoquímica , Masculino , Periodontite/patologia , Ligante RANK/análise , Distribuição Aleatória , Ratos , Reprodutibilidade dos Testes , Fosfatase Ácida Resistente a Tartarato/análise , Fatores de Tempo , Resultado do Tratamento , Microtomografia por Raio-X
2.
Acta Cir Bras ; 34(7): e201900702, 2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31531537

RESUMO

PURPOSE: To investigate the effect of intermittent vibration at different intervals on bone fracture healing and optimize the vibration interval. METHODS: Ninety sheep were randomized to receive no treatment (the control group), incision only (the sham control group), internal fixation with or without metatarsal fracture (the internal fixation group), and continuous vibration in addition to internal fixation of metatarsal fracture, or intermittent vibration at 1, 2, 3, 5, 7 and 17-day interval in addition to internal fixation of metatarsal fracture (the vibration group). Vibration was done at frequency F=35 Hz, acceleration a=0.25g, 15 min each time 2 weeks after bone fracture. Bone healing was evaluated by micro-CT scan, bone microstructure and mechanical compression of finite element simulation. RESULTS: Intermittent vibration at 7-day interval significantly improved bone fracture healing grade. However, no significant changes on microstructure parameters and mechanical properties were observed among sheep receiving vibration at different intervals. CONCLUSIONS: Clinical healing effects should be the top concern. Quantitative analyses of bone microstructure and of finite element mechanics on the process of fracture healing need to be further investigated.


Assuntos
Consolidação da Fratura/fisiologia , Fraturas Ósseas/diagnóstico por imagem , Ossos do Metatarso/lesões , Vibração/uso terapêutico , Animais , Análise de Elementos Finitos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/normas , Fraturas Ósseas/cirurgia , Fraturas Ósseas/terapia , Ossos do Metatarso/diagnóstico por imagem , Ossos do Metatarso/cirurgia , Distribuição Aleatória , Ovinos , Microtomografia por Raio-X
3.
J Appl Oral Sci ; 27: e20180689, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31411264

RESUMO

OBJECTIVE: The aim of this study was to evaluate the root canal preparation and apical enlargement of molar root canals with rotary or reciprocating heat-treated nickel-titanium (NiTi) instruments, by using micro-computed tomography (micro-CT). METHODOLOGY: Mesial root canals (n=48) of mandibular molars, with a curvature between 20° and 40°, were prepared with ProDesign Logic (PDL) 25.01 and 25.06 in rotary motion, or ProDesign R (PDR) 25.06 in reciprocating motion (PDR). Apical enlargement was performed with PDL35.01 and PDL35.05 or PDR35.05. Scanning with 9 µm resolution was performed before and after preparation, and, after apical enlargement, by using micro-CT. The percentage of volume increase, debris and untouched root canal surface, transportation, centralization and preparation time were analyzed. ANOVA and Tukey or Kruskall-Wallis and Dunn statistical tests were conducted (α=.05). RESULTS: PDL promoted a higher apical percentage of volume increase, and lower percentage of debris and untouched root canal surface than PDR 25.06 preparation in entire canal and in all thirds (P<.05). Apical enlargement with PDL 35.05 and PDR 35.05 produced a higher percentage of volume increase in the apical region in relation to the initial preparation (P<.05). PDR 35.05 and PDL 35.05 showed similar results in relation to percentage of debris and untouched root canal surface in entire canal and in all thirds (P>.05). Centralization and transportation showed no difference (P>.05). PDR required less time to perform preparation and apical enlargement (P<.05). CONCLUSIONS: The apical enlargement 35.05 with CM heat-treatment instruments using reciprocating and rotary motion reduced the percentage of debris and untouched root canal surface, without causing deviations or procedural errors. The protocol of greater apical enlargement favors the cleaning of the root canals in both kinematics. Preparation by the reciprocating system was faster than by the rotary system.


Assuntos
Instrumentos Odontológicos , Cavidade Pulpar/diagnóstico por imagem , Níquel , Preparo de Canal Radicular/instrumentação , Titânio , Análise de Variância , Cavidade Pulpar/anatomia & histologia , Desenho de Equipamento , Temperatura Alta , Humanos , Teste de Materiais , Valores de Referência , Reprodutibilidade dos Testes , Estatísticas não Paramétricas , Propriedades de Superfície , Microtomografia por Raio-X
4.
Chem Pharm Bull (Tokyo) ; 67(8): 801-809, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31366829

RESUMO

Granules prepared by a continuous twin screw granulator (TSG) were analyzed by X-ray micro-computed tomography (X-ray µCT) and the relationships between porosity of granules and granule properties were investigated. A model formulation containing ibuprofen, lactose monohydrate, microcrystalline cellulose, and hydroxypropyl cellulose was used. The porosity of granules was measured by X-ray µCT and mercury porosimetry. The data sets obtained by both methods showed linear correlation despite different values, which were attributed to the resolution of X-ray µCT and a low-signal-to-noise ratio of the original cross-sectional images. The porosity of granules measured by X-ray µCT decreased from 11-14 to 6-7% as liquid-to-solid ratio (L/S) increased, while the standard deviation (S.D.) of the porosity of individual granules decreased from 4-5 to 2%. L/S affected the porosity of granules. By contrast, the effect of screw speed was not significant. Pressure transmission, G, which indicates the liquid dispersion in wet kneaded masses, increased as the porosity of granules and the S.D. decreased. The cross-sectional images showed that granules were densified as L/S increased. Based on these results, the effect of L/S on the porosity of granules can be explained by liquid dispersion and densification of the wet granules. The porosity of granules measured by X-ray µCT showed good linear correlation with friability and drug dissolution rate (R2 = 0.9107 and 0.8834, respectively). This study revealed that the drug dissolution rate was regulated by a disintegration step in which the porosity of granules plays an important role.


Assuntos
Parafusos Ósseos , Tecnologia Farmacêutica , Microtomografia por Raio-X , Tamanho da Partícula , Porosidade , Propriedades de Superfície , Raios X
5.
Niger J Clin Pract ; 22(8): 1091-1098, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31417052

RESUMO

Aims: Our aim was to compare three different voxel sizes of CBCT images for the determination of residual filling material volume in root canals when compared with micro CT. Material and Methods: Forty-two root canals of 14 extracted human maxillary molar teeth were retreated by using ProFile® instruments. Images were obtained after retreatment by using ProMax 3D Max CBCT at 3 different voxel sizes (1) High resolution (0.1 mm); (2) High definition (0.15 mm); and (3) Normal resolution (0.2 mm). Two observers measured volumes of residual filling materials in exported CBCT images by means of 3D Doctor Software. Micro CT measurements were served as gold standard. Mann-Whitney U test and Wilcoxon Test were used for the comparison of CBCT and micro CT measurements. Statistical significance was set at P < 0.05. Results: No statistically differences were found between the two observers for all measurements (P > 0.05). There were no significant differences among different CBCT voxel sizes used (0.1 mm, 0.15 mm, and 0.2 mm) (P > 0.05). The Spearman correlation coefficients between CBCT at different voxel sizes significantly highly correlated with micro CT measurements for each observer (P < 0.05). Furthermore, no significant differences were found between the measurements obtained by the two observers in consideration to root canal location (P > 0.05). Conclusion: CBCT images may provide useful information in the volumetric assessment of the amount of residual filling material in root canals for retreatment procedures.


Assuntos
Cavidade Pulpar/diagnóstico por imagem , Dente Molar/diagnóstico por imagem , Dente Molar/cirurgia , Retratamento , Materiais Restauradores do Canal Radicular/química , Obturação do Canal Radicular/métodos , Tratamento do Canal Radicular/métodos , Tomografia Computadorizada de Feixe Cônico Espiral/métodos , Materiais Dentários , Humanos , Processamento de Imagem Assistida por Computador/métodos , Materiais Restauradores do Canal Radicular/uso terapêutico , Preparo de Canal Radicular/métodos , Microtomografia por Raio-X/métodos
6.
Artigo em Chinês | MEDLINE | ID: mdl-31327209

RESUMO

Objective:The aim of this study is to understand the imaging morphology of the humerus morphology and its associated simulated lesions, and to provide information for related research. Method:Six adult cadaveric heads fixed by formaldehyde solution (12 sides of the tibia) were used. One of the cadaveric heads (two sides of the tibia) was perforated and fractured under the microscope.The remaining 5 (10 sides) were used. The humerus was used for morphological measurements of the tibia.The tibia (12 sides) was taken out, Micro-CT scan was performed, and two-dimensional and three-dimensional reconstruction were performed using software such as Mimics 17.0 software. Result:①Stapedial morphologic observation:the head,curs and footplate of the stapes and the adjacent structures can be well displayed on two dimensional structures.②Quantitative measurements and statistics: There were no significant statistic differences about the data that had been measured between the right ears and the left ears.③Micro-CT was more clearly in displaying the precise structure of human stapes and the stapedial minute lesion comparing with that of HRCT. Conclusion:Micro-CT can accurately and clearly display the structure, morphology and simulated lesions (model) of the tibia, which provides important reference materials and methods for related research.


Assuntos
Estapédio/patologia , Cirurgia do Estribo , Estribo/diagnóstico por imagem , Adulto , Cadáver , Humanos , Microtomografia por Raio-X
7.
Int J Nanomedicine ; 14: 4881-4893, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308664

RESUMO

Purpose: This study was designed to evaluate the in vitro and in vivo biocompatibility and osteointegration of plasma-sprayed hydroxyapatite (HA)-coated polyethylene terephthalate (PET) ligaments encapsulated with a simvastatin (SV)-chitosan (CS) composite. Methods: This study compared the in vitro and in vivo bone responses to three different PET ligaments: SV/CS/PET-HA, CS/PET-HA and PET-HA. A field emission scanning electron microscope was used to characterize the morphology, and the in vitro SV release profile was analyzed. MC3T3 cells were cocultured with SV/CS/PET-HA, CS/PET-HA and PET-HA to test their biocompatibility using CCK-8 tests. Osteogenic differentiation was investigated by the expression of marker genes using qPCR. Osteointegration was performed by implanting the PET ligaments into the proximal tibia bone tunnels of male Sprague-Dawley rats for 3 weeks and 6 weeks. The bone-implant interface was evaluated by micro-computed tomography (micro-CT) and histological analysis. Results: The characteristic nanoporous structures mainly formed on the surface of the plasma-sprayed HA particles in the SV/CS/PET-HA and CS/PET-HA groups. The SV release test showed that the sustained release of simvastatin lasted for 25 days in the SV/CS/PET-HA group. The in vitro studies demonstrated that the SV/CS/PET-HA ligaments induced osteogenic differentiation in the MC3T3 cells, with higher mRNA expression levels of collagen-1, bone morphogenetic protein-2, osteocalcin and alkaline phosphatase than those in the CS/PET-HA and PET-HA ligament groups. The in vivo tests showed that both micro-CT analysis (bone mineral density and bone volume per total volume) and histological analysis (bone implant contact and interface area) revealed significantly higher peri-implant bone formation and less interface area in the SV/CS/PET-HA group than in the other groups. Conclusion: The SV-CS composite nanoporous structure was associated with the improved biocompatibility and osteogenic differentiation in vitro and enhanced osteointegration process in vivo of plasma-sprayed HA-coated PET ligaments.


Assuntos
Quitosana/química , Durapatita/farmacologia , Ligamentos/efeitos dos fármacos , Nanoporos , Osseointegração/efeitos dos fármacos , Polietilenotereftalatos/farmacologia , Sinvastatina/farmacologia , Animais , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Liberação Controlada de Fármacos , Masculino , Nanoporos/ultraestrutura , Osteocalcina/genética , Osteocalcina/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Microtomografia por Raio-X
8.
Am J Orthod Dentofacial Orthop ; 155(6): 779-790, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31153498

RESUMO

INTRODUCTION: The aim of this work was to determine how far the effects of micro-osteoperforations (MOPs) extend within bone by quantifying the damage caused and the short-term bony adaptations that occur in and around the injury site. METHODS: With the use of a split-mouth design, 34 MOPs (Propel) were randomly placed in the mandibular furcal bone of 13 beagle dogs either 2 or 4 weeks before killing them. The control side received no treatment. Vickers hardness microindentation, microscopic computed tomography, and histologic analyses were performed to evaluate the bone surrounding the MOPs. RESULTS: Microfractures produced during insertion extended ∼0.6 mm from the MOP sites. Cortical and trabecular bone were significantly less dense on the experimental than on the control side up to 4.2 mm from the edge of the MOP, but side differences were small (<5%) beyond 1.5 mm from the MOP. Experimental cortical bone was significantly softer than the control bone up to 0.8 mm from the MOP after 2 weeks of healing, and up to 0.5 mm from the MOP after 4 weeks of healing. Hematoxylin and eosin stained sections of cortical and trabecular bone showed small areas of woven bone within the MOP sites after 2 weeks, and acellular areas of bone extending ∼0.5 mm from the MOP. After 4 weeks of healing, there were greater amounts of woven bone, as well as early signs of lamellar bone, in and around the MOP sites. Markedly increased TRAP activity extending up to 2.5 mm from the MOP was evident after 2 weeks, but not after 4 weeks. Vital fluorescence staining showed diffuse bone deposition on the experimental side up to 1.5 mm from the MOP margin. CONCLUSIONS: When MOPs are performed in beagle dogs, demineralization is transient and healing of the injured area, as well as remineralization of bone affected by MOP placement, begins during the first 2 weeks. Although the transient effects extend farther, the principal effects extend only ∼1.5 mm from the MOP site.


Assuntos
Mandíbula/cirurgia , Técnicas de Movimentação Dentária/instrumentação , Adaptação Fisiológica , Animais , Parafusos Ósseos , Cães , Dureza , Imagem Tridimensional , Masculino , Mandíbula/diagnóstico por imagem , Microscopia de Fluorescência , Distribuição Aleatória , Propriedades de Superfície , Microtomografia por Raio-X
9.
Nat Commun ; 10(1): 2429, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160553

RESUMO

The WW domain-containing protein 2 (Wwp2) gene, the host gene of miR-140, codes for the Wwp2 protein, which is an HECT-type E3 ubiquitin ligases abundantly expressed in articular cartilage. However, its function remains unclear. Here, we show that mice lacking Wwp2 and mice in which the Wwp2 E3 enzyme is inactivated (Wwp2-C838A) exhibit aggravated spontaneous and surgically induced osteoarthritis (OA). Consistent with this phenotype, WWP2 expression level is downregulated in human OA cartilage. We also identify Runx2 as a Wwp2 substrate and Adamts5 as a target gene, as similar as miR-140. Analysis of Wwp2-C838A mice shows that loss of Wwp2 E3 ligase activity results in upregulation of Runx2-Adamts5 signaling in articular cartilage. Furthermore, in vitro transcribed Wwp2 mRNA injection into mouse joints reduces the severity of experimental OA. We propose that Wwp2 has a role in protecting cartilage from OA by suppressing Runx2-induced Adamts5 via Runx2 poly-ubiquitination and degradation.


Assuntos
Proteína ADAMTS5/metabolismo , Cartilagem Articular/metabolismo , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Osteoartrite/genética , Ubiquitina-Proteína Ligases/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Artrite Experimental/genética , Artrite Experimental/metabolismo , Cartilagem Articular/diagnóstico por imagem , Modelos Animais de Doenças , Humanos , Articulação do Joelho/diagnóstico por imagem , Meniscos Tibiais/cirurgia , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Osteoartrite/metabolismo , RNA Mensageiro/farmacologia , Transdução de Sinais , Crânio/diagnóstico por imagem , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Microtomografia por Raio-X , Adulto Jovem
10.
Forensic Sci Int ; 301: 225-230, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31176139

RESUMO

The agenesis of one or both upper thyroid horns (UTH) cannot be considered rare with an incidence ranging between 0.8-9.4%. Studies so far have mostly described frequencies, yet surveys on its morphology and traumatology are missing. It is unknown to what extent this anatomical variant impacts the overall symmetry of the larynx. For the trauma reconstruction after cervical trauma this knowledge is required as an asymmetric larynx can show a different fracture pattern. In this investigation, larynxes with unilateral (n=21)/bilateral (n=5) agenesis of the upper thyroid horn(s) and a control group with regular larynxes (n=23) were juxtaposed. Various measurements were taken after µ-CT scanning. In total 10 distances/angles for the thyroid cartilage and 8 for the cricoid cartilage were compared. Using intra-individual and matched pair comparisons the symmetry was assessed. The results of this investigation showed significant differences in the intra-individual and pairwise comparison for the opening angle and the length of the thyroid alae although the lateral inclination of the thyroid alae showed no significant difference. Combining these three parameters into one symmetry score, the comparison was not significant. This research demonstrates that neither unilateral nor bilateral agenesis of the UTH is related to a structural disbalance of the larynx. Thus, different fracture patterns or vulnerabilities are not to be expected.


Assuntos
Cartilagem Tireóidea/anormalidades , Cartilagem Tireóidea/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cartilagem Cricoide/anatomia & histologia , Cartilagem Cricoide/diagnóstico por imagem , Feminino , Medicina Legal , Humanos , Laringe/anatomia & histologia , Laringe/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Caracteres Sexuais , Microtomografia por Raio-X , Adulto Jovem
11.
Int J Nanomedicine ; 14: 3831-3843, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213804

RESUMO

Purpose: On the basis of reasonable superposition of various surface treatment methods, alkali-treated titanium with nanonetwork structures (TNS) was coated with mussel adhesive protein (MAP) and named TNS-MAP. The aims were to optimize the biological properties of TNS, endue it with new properties, and enhance its utility in clinical dental applications. Methods: TNS disks were coated with MAP and the product surface was characterized. Its osteogenic properties were determined by evaluating its effects on cell adhesion, cell proliferation, the expression of osteogenesis-related genes, and in vivo experiments. Results: The treated materials showed excellent hydrophilicity, good surface roughness, and advantages of both TNS and MAP. TNS-MAP significantly promoted initial cell attachment especially after 15 mins and 30 mins. At every time point, cell adhesion and proliferation, the detection rate of osteogenesis-related markers in the extracellular matrix, and the expression of osteogenesis-related genes were markedly superior on TNS-MAP than the control. The in vivo experiments revealed that TNS-MAP promoted new bone growth around the implants and the bone-implant interface. Conclusion: We verified through in vitro and in vivo experiments that we successfully created an effective TNS-MAP composite implant with excellent biocompatibility and advantages of both its TNS and MAP parent materials. Therefore, the new biocomposite implant material TNS-MAP may potentially serve in practical dentistry and orthopedics.


Assuntos
Álcalis/química , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas/química , Osseointegração/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Proteínas/farmacologia , Titânio/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Interface Osso-Implante/diagnóstico por imagem , Interface Osso-Implante/patologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Ratos Sprague-Dawley , Espectroscopia de Infravermelho com Transformada de Fourier , Microtomografia por Raio-X
12.
Int J Nanomedicine ; 14: 3845-3860, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213805

RESUMO

Background: Delay or failure of bone union is a significant clinical challenge all over the world, and it has been reported that bone marrow mesenchymal stem cells (BMSCs) offer a promising approach to accelerate bone fracture healing. Se can modulate the proliferation and differentiation of BMSCs. Se-treatment enhances the osteoblastic differentiation of BMSCs and inhibiting the differentiation and formation of mature osteoclasts. The purpose of this study was to assess the effects of porous Se@SiO2 nanocomposite on bone regeneration and the underlying biological mechanisms. Methods: We oxidized Se2- to develop Se quantum dots, then we used the Se quantum dots to form a solid Se@SiO2 nanocomposite which was then coated with polyvinylpyrrolidone (PVP) and etched in hot water to synthesize porous Se@SiO2 nanocomposite. We used XRD pattern to assess the phase structure of the solid Se@SiO2 nanocomposite. The morphology of porous Se@SiO2 nanocomposite were evaluated by scanning electron microscope (SEM) and the biocompatibility of porous Se@SiO2 nanocomposite were investigated by cell counting kit-8 (CCK-8) assays. Then, a release assay was also performed. We used a Transwell assay to determine cell mobility in response to the porous Se@SiO2 nanocomposite. For in vitro experiments, BMSCs were divided into four groups to detect reactive oxygen species (ROS) generation, cell apoptosis, alkaline phosphatase activity, calcium deposition, gene activation and protein expression. For in vivo experiments, femur fracture model of rats was constructed to assess the osteogenic effects of porous Se@SiO2 nanocomposite. Results: In vitro, intervention with porous Se@SiO2 nanocomposite can promote migration and osteogenic differentiation of BMSCs, and protect BMSCs against H2O2-induced inhibition of osteogenic differentiation. In vivo, we demonstrated that the porous Se@SiO2 nanocomposite accelerated bone fracture healing using a rat femur fracture model. Conclusion: Porous Se@SiO2 nanocomposite promotes migration and osteogenesis differentiation of rat BMSCs and accelerates bone fracture healing, and porous Se@SiO2 nanocomposite may provide clinic benefit for bone tissue engineering.


Assuntos
Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Fraturas do Fêmur/terapia , Consolidação da Fratura/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Nanocompostos/química , Osteogênese/efeitos dos fármacos , Selênio/farmacologia , Dióxido de Silício/farmacologia , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Citoproteção/efeitos dos fármacos , Modelos Animais de Doenças , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/patologia , Peróxido de Hidrogênio/toxicidade , Nanocompostos/ultraestrutura , Porosidade , Ratos Sprague-Dawley , Transdução de Sinais , Microtomografia por Raio-X
13.
Int J Nanomedicine ; 14: 3929-3941, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31213809

RESUMO

Introduction: Hierarchical nanofibrous scaffolds are emerging as a promising bone repair material due to their high cell adhesion activity and nutrient permeability. However, the existing method for hierarchical nanofibrous scaffolds fabrication is complicated and not perfectly suitable for further biomedical application in view of both structure and function. In this study, we constructed a hierarchical nanofibrous poly (l-lactic acid)/poly(ε-caprolactone) (PLLA/PCL) scaffold and further evaluated its bone healing ability. Methods: The hierarchical PLLA/PCL nanofibrous scaffold (PLLA/PCL) was prepared by one-pot TIPS and then rapidly mineralized at room temperature by an electrochemical deposition technique. After electrode-positioning at 2 V for 2 hrs, a scaffold coated with hydroxyapatite (M-PLLA/PCL) could be obtained. Results: The pore size of the M-PLLA/PCL scaffold was hierarchically distributed so as to match the biophysical structure for osteoblast growth. The M-PLLA/PCL scaffold showed better cell proliferation and osteogenesis activity compared to the PLLA/PCL scaffold. Further in vivo bone repair studies indicated that the M-PLLA/PCL scaffold could accelerate defect healing in 12 weeks. Conclusion: The results of this study implied that the as-prepared hydroxyapatite coated hierarchical PLLA/PCL nanofibrous scaffolds could be developed as a promising material for efficient bone tissue repair after carefully tuning the TIPS and electrodeposition parameters.


Assuntos
Regeneração Óssea/fisiologia , Galvanoplastia/métodos , Minerais/química , Nanofibras/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/farmacologia , Tecidos Suporte/química , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Eletricidade , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Sprague-Dawley , Crânio/diagnóstico por imagem , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , Engenharia Tecidual/métodos , Microtomografia por Raio-X
14.
Niger J Clin Pract ; 22(6): 754-762, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31187758

RESUMO

Background: Reconstruction of bone defects in oral and maxillofacial surgery has widespread uses. In recent years, the capacity of various biomaterials alone or in combination with bone graft materials to increase bone healing has been an intensive research topic. The aim of this study is to evaluate the efficacy of hyaluronic acid and/or bone graft material on bone healing in defects created in the rat mandible. Methods: In our study, rats were divided into 4 groups. Group 1 is designated to be treated with no materials, Group 2 with graft material, Group 3 with only hyaluronic acid, and Group with hyaluronic acid and graft material. A critical-size defect of 5 mm in diameter was created bilaterally in the rat mandibles and the rats were divided into the indicated groups accordingly. At the end of the postoperative 6th week, the experiment was terminated. The right halves of the mandibles were evaluated immunohistochemically and histopathologically in terms of bone healing, and the left in terms of mineralization level via microcomputed tomography. Results: Histopathological evaluation showed that healing in the empty group was significantly lower than the other groups that were treated with materials (P < 0.05); but the difference between the material-treated groups was not significant. Immunohistochemical evaluation revealed that the staining was moderately positive/strongly positive in all groups, but the difference between the groups was not significant. The highest mineralization values observed in the defected areas that belonged to 2 groups using hyaluronic acid, and the difference between them was found to be statistically significant (P < 0.05). The lowest mineralization values observed in the defected areas was most frequent in the group where only the hyaluronic acid was used, and there was a statistically significant difference between the other groups (P < 0.05). Conclusion: In conclusion, the use of hyaluronic acid alone or in combination with bone grafting has been shown to contribute positively to the improvement of bone defects in the jaw area.


Assuntos
Materiais Biocompatíveis/uso terapêutico , Transplante Ósseo , Ácido Hialurônico/uso terapêutico , Doenças Mandibulares/cirurgia , Cicatrização , Animais , Regeneração Óssea/efeitos dos fármacos , Calcificação Fisiológica/efeitos dos fármacos , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/fisiopatologia , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/patologia , Ratos , Cicatrização/efeitos dos fármacos , Microtomografia por Raio-X
15.
AAPS PharmSciTech ; 20(5): 207, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31161397

RESUMO

The use of inkjet printing for pharmaceutical manufacturing is gaining interest for production of personalized dosage forms tailored to specific patients. As part of the manufacturing, it is imperative to ensure that the correct dose is printed. The aim of this study was to use inkjet printing for manufacturing of personalized dosage forms combined with the use of near-infrared (NIR) and Raman spectroscopy as complementary analytical techniques for active pharmaceutical ingredient (API) quantification of the inkjet-printed dosage forms. Three APIs, propranolol (0.5-4.1 mg), montelukast (2.1-12.1 mg), and haloperidol (0.6-4.1 mg) were inkjet printed in 1 cm2 areas on a porous substrate. The printed doses were non-destructively analyzed by transmission NIR and Raman spectroscopy (both transmission and backscatter). X-ray computed microtomography (µ-CT) analysis was undertaken for porosity measurements of the substrate. The API content was confirmed using high-performance liquid chromatography (HPLC), and the content in the dosage forms was modeled from the NIR and Raman spectra using partial least squares regression (PLS). HPLC analysis revealed a linear correlation of the number of layers printed to the API content. The resulting PLS models for both NIR and Raman had R2 values between 0.95 and 0.99. The best predictive model was obtained using NIR, followed by Raman spectroscopy. µ-CT revealed the substrate to be highly porous and optimal for inkjet printing. In conclusion, NIR and Raman spectroscopic techniques could be used complementary as fast API quantification tools for inkjet-printed medicines.


Assuntos
Preparações Farmacêuticas/química , Impressão Tridimensional , Análise Espectral Raman/métodos , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Análise dos Mínimos Quadrados , Preparações Farmacêuticas/análise , Porosidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Microtomografia por Raio-X/métodos
16.
Nat Commun ; 10(1): 2050, 2019 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-31053719

RESUMO

The gill apparatus of gnathostomes (jawed vertebrates) is fundamental to feeding and ventilation and a focal point of classic hypotheses on the origin of jaws and paired appendages. The gill skeletons of chondrichthyans (sharks, batoids, chimaeras) have often been assumed to reflect ancestral states. However, only a handful of early chondrichthyan gill skeletons are known and palaeontological work is increasingly challenging other pre-supposed shark-like aspects of ancestral gnathostomes. Here we use computed tomography scanning to image the three-dimensionally preserved branchial apparatus in Ptomacanthus, a 415 million year old stem-chondrichthyan. Ptomacanthus had an osteichthyan-like compact pharynx with a bony operculum helping constrain the origin of an elongate elasmobranch-like pharynx to the chondrichthyan stem-group, rather than it representing an ancestral condition of the crown-group. A mixture of chondrichthyan-like and plesiomorphic pharyngeal patterning in Ptomacanthus challenges the idea that the ancestral gnathostome pharynx conformed to a morphologically complete ancestral type.


Assuntos
Evolução Biológica , Fósseis/diagnóstico por imagem , Brânquias/fisiologia , Faringe/anatomia & histologia , Tubarões/anatomia & histologia , Animais , Paleontologia , Faringe/diagnóstico por imagem , Filogenia , Tubarões/fisiologia , Esqueleto/diagnóstico por imagem , Microtomografia por Raio-X
17.
Int J Nanomedicine ; 14: 2683-2692, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31043781

RESUMO

Purpose: We aimed to fabricate guided bone regeneration (GBR) membrane using polyglycerol sebacate (PGS) and investigate the impact of scaffold pore size on osteogenesis. Materials and methods: PGS microporous membrane was fabricated by salt-leaching technique with various pore sizes. Twenty-eight male New Zealand rabbits were randomly divided into four groups: 25 µm PGS membrane, 53 µm PGS membrane, collagen membrane, and blank control group. Subsequently, standardized and critical-sized tibia defects were made in rabbits and the defective regions were covered with the specifically prepared membranes. After 4 and 12 weeks of in vivo incubation, bone samples were harvested from tibia. Micro-computed tomography scanning was performed on all bone samples. A three-dimensional visible representation of the constructs was obtained and used to compare the ratios of the ossifying volume to total construct volume (bone volume to tissue volume [BV/TV]) of each sample in different groups; then, bone samples were stained with H&E and Masson's trichrome stain for general histology. Results: At 4 weeks, the BV/TV in the 25 µm PGS group was found higher than that in the 53 µm PGS and collagen groups. At 12 weeks, the bone defect site guided by the 25 µm PGS membrane was almost completely covered by the new bone. However, the site guided by the 53 µm PGS membrane or collagen membrane was covered only most of the defects and the left part of the defect was unoccupied. Histological observation further verified these findings. Conclusion: We thus concluded that the 25 µm PGS membrane played an advantageous role during 4-12 weeks as compared with those earlier degraded counterparts.


Assuntos
Regeneração Óssea/fisiologia , Elastômeros/química , Glicerol/química , Regeneração Tecidual Guiada/métodos , Membranas Artificiais , Polímeros/química , Animais , Colágeno/química , Masculino , Osteogênese , Porosidade , Coelhos , Tíbia/diagnóstico por imagem , Tíbia/cirurgia , Microtomografia por Raio-X
18.
J Biomed Nanotechnol ; 15(6): 1172-1184, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31072426

RESUMO

Magnesium is an attractive candidate for orthopedic implants due to its similar mechanical properties to human bone and biodegradability. However, the high corrosion rate of magnesium accompanying with high pH value and poor osteogenic activity hinder its further application. In this study, we employed micro arc oxidation (MAO) to improve corrosion resistance by introduce nanoporous coating on AZ91 magnesium. Meanwhile, we added lithium, an angiogenic and osteogenic element, to the coating (named as Li-MAO) by reaction in a lithium-containing electrolyte to simultaneously enhance angiogenic and osteogenic activity of AZ91. The favorable corrosion resistance of Li-MAO was verified by electrochemical and immersion test in vitro. Better biocompatibility was observed in Li-MAO samples by cell counting kit-8 (CCK-8) and live/dead assay. The in vitro results of immunofluorescence staining, Alizarin red staining and osteogenic-related genes expression indicated better osteogenic ability of Li-MAO group, which may result from the activation the Wnt/ß-catenin pathway. In vitro angiogenic tests also demonstrated better angiogenesis in Li-MAO group. A bone defect repair model was built to evaluate the in vivo osseointegration of samples. The outcomes of micro-computed tomography (Micro-CT) scanning, sequential fluorochrome labeling and Van Gieson staining suggested better in vivo bone repair ability of Li-MAO than other groups. Our promising results both in vitro and in vivo demonstrated that lithium-containing nanoporous coating can improve corrosion resistance, angiogenesis and osseointegration of magnesium alloy, which may forward the clinic application of Li-MAO magnesium.


Assuntos
Nanoporos , Ligas , Materiais Revestidos Biocompatíveis , Corrosão , Lítio , Magnésio , Osseointegração , Oxirredução , Microtomografia por Raio-X
19.
Am J Orthod Dentofacial Orthop ; 155(5): 681-692, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31053284

RESUMO

PURPOSE: The purpose of this study was to determine how micro-osteoperforations (MOPs) affect tooth movements, bone turnover, bone density, and bone volume. METHODS: A split-mouth experimental design with 7 beagle dogs was used to evaluate bone surrounding maxillary second premolars that had been retracted for 7 weeks. One month after the maxillary third premolars were extracted, 8 MOPs (1.5 mm wide and 7 mm deep) were created without flaps with the use of the Propel device (6 were placed 3 mm distal to the second premolar and 2 were placed in the premolar furcation) on one randomly chosen side. The maxillary second premolars were retracted bilaterally with the use of 200 g nickel-titanium closed coil springs. Tooth movements were measured intraorally and radiographically. Microscopic computed tomography was used to evaluate the material density and volume fraction of bone distal to the premolars. Hematoxylin and eosin-stained and fluorescent sections were used to examine the bone remodeling. RESULTS: Neither the intraoral (P = 0.866) nor radiographic (P = 0.528) measures showed statistically significant side differences in tooth movements. There also were no statistically significant differences in the density (P = 0.237) or volume fraction (P = 0.398) of bone through which the premolars were being moved. Fluorescent and histologic evaluations showed no apparent differences in osteoblasts, osteoclasts, or mineralization of bone near the teeth being moved. Bone healing was evident in and near the MOP sites, which had nearly but not completely healed after 7 weeks. Regions of acellular bone were evident extending ∼0.8 mm from the MOP sites. CONCLUSIONS: MOPs placed 3 mm away from teeth do not increase tooth movements and have limited and transitory effect on bone.


Assuntos
Prótese Dentária , Técnicas de Movimentação Dentária/instrumentação , Animais , Dente Pré-Molar/cirurgia , Densidade Óssea/fisiologia , Remodelação Óssea/fisiologia , Planejamento de Prótese Dentária , Cães , Maxila/patologia , Microtomografia por Raio-X
20.
Biomed Res Int ; 2019: 4985121, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093500

RESUMO

Objectives: The study aimed to compare the accuracy of different methods of data acquisition and data reconstruction and to assess their usefulness for 3D printing of tooth replicas. Methods: 3-dimensional models of molar and canine teeth obtain utilizing CBCT examination with different protocols, and optical scanning was compared with models derived from micro-computed (micro-CT) examination using Geomagic Studio Qualify software. A pairwise comparison of 3D models with analysis of standard deviation and the value of the mean distance of given surfaces was performed. Results: Standard deviation and the value of the mean distance were lowest for optical scanning followed by CBC in high and standard resolution in all tested protocols. Models, obtained with high-resolution CBCT protocols, of teeth in and outside of alveolar bone showed similar average distance parameters, but standard deviation parameter was significantly lower for models of teeth scanned outside of the socket. Good surface representation on all models was seen at relatively smooth areas while in areas of high changes in the geometry CBCT based models performed inferiorly to those obtained from an optical scanner. Conclusions: In case of teeth of noncomplicated texture, independently from a position (within or outside the alveolar socket), the high-resolution CBCT seems to be a sufficient method to obtain data for 3D printed tooth replica. Optical scanning performs better when a detailed replica is necessary.


Assuntos
Imagem Tridimensional , Imagem Óptica , Tomografia Computadorizada por Raios X , Dente/diagnóstico por imagem , Animais , Tomografia Computadorizada de Feixe Cônico , Modelos Dentários , Cães , Humanos , Microtomografia por Raio-X
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