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1.
Cell Tissue Res ; 376(2): 221-231, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30635775

RESUMO

Testosterone (T) has been suggested as a promising agent in the bone osteointegration when incorporated in a bioceramic/polymer combination for the local application. The objective of this study was to evaluate the activity of a testosterone composite of poly (lactic-co-glycolic acid) (PLGA), polycaprolactone (PCL), and biphasic calcium phosphate (BCP) as a strategy for enhancing its osteogenic effect and to evaluate tissue response to the composite implantation. PLGA/PCL/BCP/T and PLGA/PCL/BCP composites were prepared and characterized using thermal analysis. Composite morphology and surface characteristics were assessed by SEM and EDS. The evaluations of in vitro effects of testosterone composite on osteoblasts viability, alkaline phosphatase activity, collagen production, osteocalcin concentration, quantification of mineralization, and nitric oxide concentration, after 7, 14, and 21 days. Testosterone was successfully incorporated and composites showed a homogeneously distributed porous structure. The PLGA/PCL/BCP/T composite had a stimulatory effect on osteoblastic activity on the parameters evaluated, except to nitric oxide production. After 60 days, the PLGA/PCL/BCP/T composite showed no chronic inflammatory infiltrate, whereas the PLGA/PCL/BCP composite showed mild chronic inflammatory infiltrate. Angiogenesis, cellular adsorption, and fibrous deposit were observed on the surfaces of implanted composites. The composites in combination with testosterone can be exploited to investigate the use of this scaffold for bone integration.


Assuntos
Materiais Biocompatíveis , Osteogênese/efeitos dos fármacos , Testosterona/farmacologia , Alicerces Teciduais/química , Fosfatase Alcalina/metabolismo , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biomineralização/efeitos dos fármacos , Sobrevivência Celular , Células Cultivadas , Colágeno/metabolismo , Hidroxiapatitas/química , Masculino , Neovascularização Fisiológica/efeitos dos fármacos , Óxido Nítrico/metabolismo , Osteoblastos/citologia , Osteocalcina/metabolismo , Poliésteres/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Ratos , Ratos Wistar
2.
J Mater Sci Mater Med ; 23(11): 2751-9, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22886580

RESUMO

In the current study, we characterized the polycaprolactone (PCL), poly(lactic acid-co-glycolic acid) (PLGA), and biphasic calcium phosphate (BCP) composites coated with testosterone propionate (T) using Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (XRD). Osteoblastic cells were seeded with PCL/BCP, PCL/BCP/T, PLGA/PCL/BCP and PLGA/PCL/BCP/T scaffolds, and cell viability, proliferation, differentiation and adhesion were analyzed. The results of physic-chemical experiments showed no displacements or suppression of bands in the FTIR spectra of scaffolds. The XRD patterns of the scaffolds showed an amorphous profile. The osteoblastic cells viability and proliferation increased in the presence of composites with testosterone over 72 h, and were significantly greater when PLGA/PCL/BCP/T scaffold was tested against PCL/BCP/T. Furthermore alkaline phosphatase production was significantly greater in the same group. In conclusion, the PLGA/PCL/BCP scaffold with testosterone could be a promising option for bone tissue applications due to its biocompatibility and its stimulatory effect on cell proliferation.


Assuntos
Materiais Biocompatíveis , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cerâmica/química , Polímeros/química , Testosterona/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Adesão Celular , Masculino , Microscopia Eletrônica de Varredura , Difração de Pó , Ratos , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Alicerces Teciduais
3.
Beilstein J Org Chem ; 8: 1867-76, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23209524

RESUMO

Organic-inorganic magnetic hybrid materials (MHMs) combine a nonmagnetic and a magnetic component by means of electrostatic interactions or covalent bonds, and notable features can be achieved. Herein, we describe an application of a self-assembled material based on ferrite associated with ß-cyclodextrin (Fe-Ni/Zn/ßCD) at the nanoscale level. This MHM and pure ferrite (Fe-Ni/Zn) were used as an adsorbent system for Cr(3+) and Cr(2)O(7) (2-) ions in aqueous solutions. Prior to the adsorption studies, both ferrites were characterized in order to determine the particle size distribution, morphology and available binding sites on the surface of the materials. Microscopy analysis demonstrated that both ferrites present two different size domains, at the micro- and nanoscale level, with the latter being able to self-assemble into larger particles. Fe-Ni/Zn/ßCD presented smaller particles and a more homogeneous particle size distribution. Higher porosity for this MHM compared to Fe-Ni/Zn was observed by Brunauer-Emmett-Teller isotherms and positron-annihilation-lifetime spectroscopy. Based on the pKa values, potentiometric titrations demonstrated the presence of ßCD in the inorganic matrix, indicating that the lamellar structures verified by transmission electronic microscopy can be associated with ßCD assembled structures. Colloidal stability was inferred as a function of time at different pH values, indicating the sedimentation rate as a function of pH. Zeta potential measurements identified an amphoteric behavior for the Fe-Ni/Zn/ßCD, suggesting its better capability to remove ions (cations and anions) from aqueous solutions compared to that of Fe-Ni/Zn.

4.
Carbohydr Polym ; 98(1): 726-35, 2013 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-23987405

RESUMO

In the present study we evaluated the complexation of daidzein/genistein/glycitein, present in an isoflavone enriched fraction (IEF), with ß-cyclodextrin and 2-hydroxypropyl-ß-cyclodextrin (HPßCD). Based on the increased solubility and higher complexation efficiency, IEF and HPßCD solid complexes were prepared by kneading, freeze-drying, co-evaporation, spray-drying and microwave. The solid complexes were characterized using Fourier transformed-infrared spectroscopy, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and nuclear magnetic resonance spectroscopy, and the isoflavone content and solubility were determined by liquid chromatography. The results suggest that the isoflavones daidzein, genistein and glycitein may be externally associated to HPßCD as well as that isoflavones/HPßCD inclusion complexes are formed through the insertion of B-ring into the cyclodextrin cavity. Except for the freeze-dried IEF/HPßCD solid complex, all complexes showed similar content and solubility. In conclusion, the three isoflavones showed to be able to simultaneously complex with HPßCD.


Assuntos
Ciclodextrinas/química , Glycine max/química , Isoflavonas/química , Solubilidade
5.
Int J Pharm ; 436(1-2): 478-85, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22772486

RESUMO

The aim of the present work was to evaluate the antidepressant like-effect and plasma concentration of Sertraline (SRT) using an inclusion complex (IC) with ß-cyclodextrin (ßCD) in mice. This supramolecular system was prepared using two different molar ratios at 1:1 and 1:2 SRT:ßCD and both were characterized to assess the drug inclusion into the host cavity. Based on the X-ray powder diffraction, Fourier transform infrared spectroscopy and thermal analysis the interaction between host and guest molecules could be suggested. This result indicates that the freeze drying process was efficient to prepare the ICs, when these are compared with the physical mixtures. By comparing the solid state results of 1:1 and 1:2 ICs no significant chemical or structural changes were identified between these systems. However, in vivo experiments indicated that the host-guest ratio was able to modify the SRT activity. Mice treated with both ICs (20 mg kg(-1), p.o.) have shown lower immobility time in the tail suspension test in comparison with mice treated with free SRT (20 mg kg(-1), p.o.). Mice spontaneous locomotor activity was not affected by any treatment. Higher SRT plasma concentration was determined after 30 min of treatment with 1:1 IC in comparison with free SRT, demonstrating the IC greater drug transport efficacy.


Assuntos
Antidepressivos/farmacologia , Sertralina/farmacologia , beta-Ciclodextrinas/farmacologia , Animais , Antidepressivos/sangue , Antidepressivos/química , Elevação dos Membros Posteriores , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Difração de Pó , Sertralina/sangue , Sertralina/química , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , beta-Ciclodextrinas/química
6.
Int J Pharm ; 421(1): 24-33, 2011 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-21963467

RESUMO

Sertraline (SRT) is a widely used antidepressant whose poor solubility in water limits its oral applicability. Thus, the aim of this work was the evaluation of a multi-equilibrium system based on ß-cyclodextrin (ßCD) and SRT. The inclusion compounds (ICs) were investigated by infrared spectroscopy, isothermal titration calorimetry (ITC) and (1)H and 2D ROESY nuclear magnetic resonance experiments. SRT solubility was predicted in vitro in water and biomimetic fluids. The SRT in presence of ßCD at 1:1 and 1:2 molar ratios was more soluble than free SRT in all biomimetics media investigated. The FTIR-HATR showed that ßCD νC-O-C stretching band was reduced in presence of SRT, suggesting the interactions between them. Additionally, titration process and Job's plot provided information on the ICs stoichiometry and evidenced the multi-equilibrium coexistence in aqueous solution. According to the ITC, SRT:ßCD interaction process was spontaneous and exothermic with a high affinity binding constant (K=14,726 M(-1)). Additionally, the stoichiometry coefficient (n) was 1.63, which was comparable to that found by FITR-HATR. The (1)H and 2D ROESY verified multiple SRT sites included into the host cavity. Theoretical calculations depicted the relative energy of different proposed ICs structures, in which the 1:2 IC was the most stable.


Assuntos
Antidepressivos/química , Sertralina/química , beta-Ciclodextrinas/química , Calorimetria , Liofilização , Espectroscopia de Ressonância Magnética , Solubilidade , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier
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