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1.
Braz Oral Res ; 33: e060, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31365705

RESUMO

This study evaluated the effect of hypertension on tissue response and biomineralization capacity of white Mineral Trioxide Aggregate (MTA), High-plasticity MTA (MTA HP), and Biodentine® (BDT) in rats. Polyethylene tubes filled with MTA, MTA HP, BDT, and the control group (empty tubes) were placed into the dorsal subcutaneous tissue of 32 male rats (16 normotensive (NT) and 16 hypertensive rats - 8 per group). After 7 and 30 days, the polyethylene tubes surrounded by connective tissue were removed, fixed, and embedded in histological resin. The mean number of inflammatory cells was estimated in HE-stained sections, biomineralization was quantified as area (µm2) by Kossa (VK) staining, and examination by polarized light (LP) microscopy was performed. The differences amongst the groups were analyzed statistically by the Mann-Whitney or Student's t test, according to Shapiro-Wilk test of normality (p < 0.05). The inflammatory responses to all materials were greater in hypertensive rats than in NT rats (p < 0.05). Positive VK staining in MTA and BDT were more pronounced in NT rats at 7 and 30 days (p < 0.05). Birefringent structures in LP for MTA, MTA HP, and BDT were more pronounced in NT rats at 7 days (p<0.05). In rats, hypertension was able to increase inflammatory infiltrate and decrease biomineralization of the tested materials.


Assuntos
Compostos de Alumínio/farmacologia , Materiais Biocompatíveis/farmacologia , Biomineralização/fisiologia , Compostos de Cálcio/farmacologia , Hipertensão/fisiopatologia , Óxidos/farmacologia , Silicatos/farmacologia , Tela Subcutânea/efeitos dos fármacos , Tela Subcutânea/fisiopatologia , Animais , Combinação de Medicamentos , Hipertensão/complicações , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Teste de Materiais , Microscopia de Polarização , Ratos Wistar , Reprodutibilidade dos Testes , Tela Subcutânea/patologia , Fatores de Tempo
2.
J Photochem Photobiol B ; 197: 111541, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31272033

RESUMO

Here, we report the novel fabrication of ZnO nanoparticles using the Costus igneus leaf extract. Gas chromatography-mass spectrometry (GC-MS) and proton nuclear magnetic resonance (1H NMR) spectroscopy to determine the bioactive components present in the plant extract. The synthesis of Ci-ZnO NPs (C. igneus- coated zinc oxide nanoparticles) was accomplished using a cost-effective and simple technique. Ci-ZnO NPs were specified using UV-visible spectroscopy, FTIR, XRD, and TEM. Ci-ZnO NPs was authenticated by UV-Vis and exhibited a peak at 365 nm. The XRD spectra proved the crystalline character of the Ci-ZnO NPs synthesized as hexagonal wurtzite. The FTIR spectrum illustrated the presence of possible functional groups present in Ci-ZnO NPs. The TEM micrograph showed evidence of the presence of a hexagonal organization with a size of 26.55 nm typical of Ci-ZnO NPs. The α-amylase and α-glucosidase inhibition assays demonstrated antidiabetic activity of Ci-ZnO NPs (74 % and 82 %, respectively), and the DPPH [2,2-diphenyl-1-picrylhydrazyl hydrate] assay demonstrated the antioxidant activity of the nanoparticles (75%) at a concentration of 100 µg/ml. The Ci-ZnO NPs exhibited promising antibacterial and biofilm inhibition activity against the pathogenic bacteria Streptococcus mutans, Lysinibacillus fusiformis, Proteus vulgaris, and Vibrio parahaemolyticus. Additionally, the Ci-ZnO NPs showed biocompatibility with mammalian RBCs with minimum hemolytic activity (0.633 % ±â€¯0.005 %) at a concentration of 200 µg/ml.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/química , Biofilmes/efeitos dos fármacos , Nanopartículas Metálicas/química , Extratos Vegetais/química , Óxido de Zinco/química , Antibacterianos/síntese química , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Costus/química , Costus/metabolismo , Eritrócitos/citologia , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/fisiologia , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/fisiologia , Química Verde , Hemólise/efeitos dos fármacos , Humanos , Insulina/química , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Extratos Vegetais/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , alfa-Amilases/antagonistas & inibidores , alfa-Amilases/metabolismo
3.
J Photochem Photobiol B ; 196: 111508, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31152936

RESUMO

Cardiovascular malady (CVM) isn't just the essential driver of death in created western nations, yet additionally, its sickness load is expanding in China. Oxidative pressure initiated free radicals assume a basic job in cell forms involved in atherosclerosis and numerous other heart illnesses. Quercetin (QC) is cancer prevention agents medicate which is demonstrated that successfully secures against CVMs. Encapsulations of medications in polymeric materials are generally utilized in creating continued and controllable medication discharge, or to keep away from the debasement of non-discharged medications. In this present work, a novel arrangement of polymeric superparamagnetic nano-silica (SiN)@poly(lactic-co-glycolic acid) (PLGA) (SiN@PLGA) stacked with QC was created by means of lyophilization method so as to improve poor watery solvency and steadiness of the medication with the point of preventing atherosclerosis. The aftereffects of SEM investigation and the checking, TEM affirmed the manufacture of the circular nanocomposite, smooth surface, and thin size dispersion. The discharge profile of QC from the particles was explored by deciding the medication sum discharged at explicit interims for by iridescence. The data got from this investigation encourages the structure and manufacture of nanocomposite as conceivable conveyance frameworks for epitome, assurance and controlled arrival of the flavonoid QC which is expecting to secure against CVMs.


Assuntos
Nanocompostos/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Quercetina/química , Dióxido de Silício/química , Animais , Aterosclerose/patologia , Aterosclerose/prevenção & controle , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Camundongos , Miocárdio/metabolismo , Miocárdio/patologia , Nanocompostos/toxicidade , Quercetina/metabolismo , Quercetina/uso terapêutico
4.
Bone Joint J ; 101-B(6_Supple_B): 62-67, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31146557

RESUMO

AIMS: The purpose of this study was to evaluate the biological fixation of a 3D printed porous implant, with and without different hydroxyapatite (HA) coatings, in a canine model. MATERIALS AND METHODS: A canine transcortical model was used to evaluate the characteristics of bone ingrowth of Ti6Al4V cylindrical implants fabricated using laser rapid manufacturing (LRM). At four and 12 weeks post-implantation, we performed histological analysis and mechanical push-out testing on three groups of implants: a HA-free control (LRM), LRM with precipitated HA (LRM-PA), and LRM with plasma-sprayed HA (LRM-PSHA). RESULTS: Substantial bone ingrowth was observed in all LRM implants, with and without HA, at both time periods. Bone ingrowth increased from 42% to 52% at four weeks, to 60% to 65% at 12 weeks. Mechanical tests indicated a minimum shear fixation strength of 20 MPa to 24 MPa at four weeks, and 34 MPa to 40 MPa at 12 weeks. There was no significant difference in the amount of bone ingrowth or in the shear strength between the three implant types at either time period. CONCLUSION: At four and 12 weeks, the 3D printed porous implants exhibited consistent bone ingrowth and high mechanical shear strength. Based on the results of this study, we confirmed the suitability of this novel new additive manufacturing porous material for biological fixation by bone ingrowth. Cite this article: Bone Joint J 2019;101-B(6 Supple B):62-67.


Assuntos
Fêmur/fisiologia , Osseointegração/fisiologia , Próteses e Implantes , Animais , Materiais Biocompatíveis/farmacologia , Fenômenos Biomecânicos/fisiologia , Cães , Durapatita/farmacologia , Fêmur/ultraestrutura , Masculino , Microscopia Eletrônica de Varredura , Porosidade , Impressão Tridimensional
5.
Carbohydr Polym ; 219: 240-250, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151522

RESUMO

In this study, Schiff bases of chitosan (CS) were synthesized using citronellal, citral, and their derivatives containing selenium and sulfur. Organoselenium and organosulfur compounds show attractive biological and pharmaceutical activities, which can be beneficial to CS-based materials. From the characterization analyses, it was found that the CS-derivatives containing organoselenium and organosulfur compounds exhibited the highest conversion degrees (23 and 28%). Biological assays were conducted using films prepared by the blending of CS-derivatives and poly(vinyl alcohol). The antimicrobial evaluation indicated that the film prepared with the sulfur-containing CS was the most active against the tested pathogens (Escherichia coli, Staphylococcus aureus, and Candida albicans) since it reduced considerably their counts (42.5%, 17.4%, and 18.7%). Finally, in vivo assays revealed that this film attenuates atopic dermatitis-like symptoms in mice by suppressing the increase of myeloperoxidase (MPO) activity and reactive species (RS) levels induced by 2,4-dinitrochlorobenzene (DNCB). In summary, CS-derivatives containing chalcogens, mainly organosulfur, are potential candidates for biomedical applications such as for the treatment of chronic skin diseases.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Quitosana , Dermatite Atópica/tratamento farmacológico , Compostos Organosselênicos/farmacologia , Bases de Schiff/farmacologia , Animais , Candida albicans/efeitos dos fármacos , Calcogênios/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Dermatite Atópica/induzido quimicamente , Dinitroclorobenzeno/química , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos
6.
Carbohydr Polym ; 219: 261-268, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31151524

RESUMO

Chitosan-based films with incorporated supercritical CO2 hop extract (HE) were developed and evaluated regarding structural, physicochemical, and antibacterial properties. The morphological and spectroscopic analyses have confirmed successful incorporation of HE into the polymer matrix, which affected films' structure and visual appearance. The presence of HE has caused a reduction in the hydrophilic character of films, but also provided a complete UV light blockage at wavelengths below 350 nm. Furthermore, a declining trend of tensile strength (from 14.4 MPa to 6.4 MPa) and Young's modulus (from 218.8 MPa to 26.9 MPa), as well as an ascending trend of elongation at break (from 10.7% to 35.1%), have been observed after the extract incorporation. The total phenolic content in the films was up to ∼13 mgGAE gfilm-1. Besides, the HE-loaded films exhibited antibacterial activity against foodborne pathogen Bacillus subtilis.


Assuntos
Antibacterianos , Bacillus subtilis/efeitos dos fármacos , Materiais Biocompatíveis , Quitosana , Extratos Vegetais , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Dióxido de Carbono/química , Quitosana/química , Quitosana/farmacologia , Módulo de Elasticidade , Interações Hidrofóbicas e Hidrofílicas , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Resistência à Tração
7.
Expert Rev Med Devices ; 16(7): 603-616, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31154869

RESUMO

INTRODUCTION: Blood-recirculating medical devices, such as mechanical circulatory support (MCS), extracorporeal membrane oxygenators (ECMO), and hemodialyzers, are commonly used to treat or improve quality of life in patients with cardiac, pulmonary, and renal failure, respectively. As part of their regulatory approval, guidelines for thrombosis evaluation in pre-clinical development have been established. In vitro testing evaluates a device's potential to produce thrombosis markers in static and dynamic flow loops. AREAS COVERED: This review focuses on in vitro static and dynamic models to assess thrombosis in blood-recirculating medical devices. A summary of key devices is followed by a review of molecular markers of contact activation. Current thrombosis testing guidance documents, ISO 10993-4, ASTM F-2888, and F-2382 will be discussed, followed by analysis of their application to in vitro testing models. EXPERT OPINION: In general, researchers have favored in vivo models to thoroughly evaluate thrombosis, limiting in vitro evaluation to hemolysis. In vitro studies are not standardized and it is often difficult to compare studies on similar devices. As blood-recirculating devices have advanced to include wearable and implantable artificial organs, expanded guidelines standardizing in vitro testing are needed to identify the thrombotic potential without excessive use of in vivo resources during pre-clinical development.


Assuntos
Equipamentos e Provisões , Modelos Biológicos , Trombose/diagnóstico , Materiais Biocompatíveis/farmacologia , Biomarcadores/metabolismo , Humanos , Qualidade de Vida , Trombose/terapia
8.
Chem Soc Rev ; 48(15): 4317-4335, 2019 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-31225558

RESUMO

Biocompatible ionic liquids (Bio-ILs) are an eco- and bio-friendly family of ionic liquids (ILs) useful in applications ranging from the electrochemical to the biomedical fields. The most promising strategies for their synthesis involve using molecules from bio-renewable sources as a basis for both the anionic and cationic counterparts of the Bio-ILs structure. Several studies have been conducted on Bio-IL properties, including their impact on the environment and health safety. Herein, we review progress and strategies towards the synthesis of Bio-ILs and address their ecotoxicological and biological impact. Furthermore, we discuss the impact of using these compounds in a diverse range of applications, with some insights toward their use in the development of improved technologies.


Assuntos
Materiais Biocompatíveis/farmacologia , Tecnologia Biomédica , Líquidos Iônicos/farmacologia , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Humanos , Líquidos Iônicos/síntese química , Líquidos Iônicos/química
9.
Int J Nanomedicine ; 14: 3893-3909, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239663

RESUMO

Background: Photothermal and chemotherapy treatment has been frequently studied for cancer therapy; however, chemotherapy is equally toxic to both normal and cancer cells. The clinical application value of most kinds of photothermal transforming agents remains limited, due to their poor degradation and minimal accumulation in tumors. Materials and methods: We reported the synthesis of photothermal transforming agents (MoS2) and chemotherapeutic (doxorubicin, DOX) co-loaded electrospun nanofibers using blend electrospinning for the treatment of postoperative tumor recurrence. Results: Under the irradiation of an 808 nm laser, the as-prepared chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an admirable photothermal conversion capability with a photothermal conversion efficiency of 23.2%. These composite nanofibers are in vitro and in vivo biocompatible. In addition, they could control the sustained release of DOX and the generated heat can sensitize the chemotherapeutic efficacy of DOX via enhancing its release rate. Their chemo-/photothermal combined therapy efficiency was systematically studied in vitro and in vivo. Instead of circulating with the body fluid, MoS2 was trapped by the nanofibrous matrix in the tumor and so its tumor-killing ability was not compromised, thus rendering this composite nanofiber a promising alternative for future clinical translation within biomedical application fields. Conclusion: Chitosan/polyvinyl alcohol/MoS2/DOX nanofibers showed an excellent photothermal conversion capability with a photothermal conversion efficiency of 23.2% and can completely inhibit the postoperative tumor reoccurrence.


Assuntos
Dissulfetos/química , Doxorrubicina/uso terapêutico , Molibdênio/química , Nanofibras/química , Nanotecnologia/métodos , Neoplasias/terapia , Fototerapia , Animais , Materiais Biocompatíveis/farmacologia , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Reagentes para Ligações Cruzadas/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HT29 , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanofibras/ultraestrutura , Recidiva Local de Neoplasia/patologia , Neoplasias/sangue , Neoplasias/patologia , Neoplasias/cirurgia , Padrões de Referência , Resultado do Tratamento
10.
Int. j. morphol ; 37(2): 685-689, June 2019. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1002277

RESUMO

El Theracal TM LC es un cemento silicato de calcio (Ca) modificado con resina (SMCR) que ha demostrado ser un material ideal para el tratamiento dentino-pulpar por su alta tasa de formación de calcio. Los biomateriales por su contenido de Ca tienden a tener un aumento en su biodisponibilidad, estimulando la formación del puente dentario atreves de las células involucradas en la formación de tejidos mineralizados, promoviendo la diferenciación de fibroblastos en odontoblastos y aumentando la actividad de la enzima pirofostasa responsable en la mineralización de la dentina. El presente estudio con el objetivo de evaluar la respuesta inflamatoria a Theracal TM LC subcutáneamente en ratas Wistar. Fueron usados seis ratas cepa Wistar en las cuales se realizaron cuatro bolsillos quirúrgicos subcutáneos. Cada uno de estos bolsillos se determinó como cuadrante distinto, conteniendo los siguientes implantes: 1 Theracal TM LC en tubo polietileno, 2 tubo de polietileno, 3 Theracal TM LC directo y 4 como control. Las muestras histológicas se procesaron y se evaluaron distintos tipos celulares mediante conteo a microscopio de luz a 100X utilizando las tinciones H&E y AT pH 2.3. Los resultados mostraron que existen diferencias significativas en todos los tipos celulares observados durante los diferentes tiempos de exposición. Las diferencias en los tipos celulares observados podrían ser debido al tiempo de exposición al Theracal TM LC, al tubo polietileno y a ambos. El tejido evaluado del implante del tubo polietileno y al tubo polietileno con Theracal TM LC, presentan mayor respuesta inflamatoria, a diferencia en el tejido implantado con Theracal TM LC directamente.


TheraCalTM LC is a resin-modified calcium silicate (Ca) resin (SMCR) that has proven to be an ideal material for dentin-pulp treatment due to its high rate of calcium formation. Biomaterials due to their Ca content tend to have an increase in their bioavailability, stimulating the formation of the dental bridge through the cells involved in the formation of mineralized tissues, promoting the differentiation of fibroblasts in odontoblasts and increasing the activity of the pyrophosphate enzyme responsible in dentin mineralization. The present study aimed to evaluate the inflammatory response to TheracalTM LC subcutaneously in Wistar rats. Six Wistar strain rats were used in which four subcutaneous surgical pockets were made. Each of these pockets was determined as a different quadrant, containing the following implants: 1 TheracalTM LC in polyethylene tube, 2 polyethylene tubes, 3 TheracalTM LC direct and 4 as control. The histological samples were processed, and different cell types were evaluated by light microscopy at 100X using the H&E and AT pH 2.3 stains. The results showed that there are significant differences in all cell types observed during the different exposure times. The differences in the cell types observed could be due to the exposure time to TheracalTM LC, to the polyethylene tube and to both. The evaluated tissue of the polyethylene tube implant and the polyethylene tube with TheracalTM LC present a greater inflammatory response, unlike in the tissue implanted with TheracalTM LC directly.


Assuntos
Animais , Ratos , Compostos de Cálcio/farmacologia , Resinas Compostas/farmacologia , Tela Subcutânea/efeitos dos fármacos , Inflamação , Materiais Biocompatíveis/farmacologia , Ratos Wistar , Silicatos
11.
Talanta ; 200: 212-217, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31036175

RESUMO

A surface-enhanced Raman scattering (SERS) imaging probe and drug carrier based on zeolitic imidazolate framework (ZIF-8)-coated Au@Ag core-shell nanorod has been developed. Strong Raman signal is generated by a reporter molecule of 4-aminothiophenol (4-ATP) adsorbed on Au@Ag core-shell nanorod, endowing the probe with function of SERS imaging. Further coating of ZIF-8 on Au@Ag core-shell nanorod offered high loading capacity for anti-cancer drugs, doxorubicin (DOX), as well as improved the stability and biocompatibility of the SERS tag due to the protection of ZIF-8 shell. After immobilization of folic acid onto the Au@Ag NRs4-ATP@ZIF-8, the SERS probes were successfully applied to the targeted SERS imaging of HeLa, MCF-7, LNCaP, QGY-7703, HCT116 and MDA-MB-231 cells with low cytotoxicity, and further applied to the image of tumor tissue of human colon cancer. In vitro cell cytotoxicity confirmed that DOX-loaded SERS probes had potential therapeutic effect compared with the free drug. All of these original results contribute to develop potential biocompatible nanosystem integrating diagnosis and therapy.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Materiais Biocompatíveis/farmacologia , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos , Nanopartículas/química , Nanotubos/química , Zeolitas/farmacologia , Antibióticos Antineoplásicos/química , Materiais Biocompatíveis/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Ouro/química , Ouro/farmacologia , Células HeLa , Humanos , Células MCF-7 , Imagem Óptica , Prata/química , Prata/farmacologia , Análise Espectral Raman , Relação Estrutura-Atividade , Propriedades de Superfície , Zeolitas/química
12.
Expert Rev Med Devices ; 16(7): 549-553, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31144544

RESUMO

Introduction: Cerebrospinal fluid leakage is a complication after intradural surgery and is associated with severe secondary complications like compromised wound healing and meningitis. Dural sealants are meant to augment the primary dural closure in order to achieve a watertight closure. Areas covered: This review summarizes the efficacy of currently available dural sealants. Potential future improvements and biomaterials are discussed. Expert opinion: The use of a dural sealant seems to be the logical method to prevent CSF leakage. However, based on the efficacy of currently available dural sealants according to systematic reviews and in vitro studies, a significant effective dural sealant seems is still lacking. A new dural sealant has to be thoroughly assessed before clinical application in in vitro, in vivo and clinical trials. A new research area within sealant development might be the introduction of dural sealants with both antimicrobial and analgesic properties.


Assuntos
Materiais Biocompatíveis/farmacologia , Vazamento de Líquido Cefalorraquidiano/etiologia , Vazamento de Líquido Cefalorraquidiano/terapia , Dura-Máter/cirurgia , Humanos , Polímeros/farmacologia , Resultado do Tratamento
13.
Int J Mol Sci ; 20(9)2019 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-31058825

RESUMO

Mg-based alloys have great potential for development into fixation implants because of their highly biocompatible and biodegradable metallic properties. In this study, we sought to determine the biocompatibility of Mg60Zn35Ca5 bulk metallic glass composite (BMGC) with fabricated implants in a rabbit tendon-bone interference fixation model. We investigated the cellular cytotoxicity of Mg60Zn35Ca5 BMGC toward rabbit osteoblasts and compared it with conventional titanium alloy (Ti6Al4V) and polylactic acid (PLA). The results show that Mg60Zn35Ca5 BMGC may be classed as slightly toxic on the basis of the standard ISO 10993-5. We further characterized the osteogenic effect of the Mg60Zn35Ca5 BMGC extraction medium on rabbit osteoblasts by quantifying extracellular calcium and mineral deposition, as well as cellular alkaline phosphatase activity. The results of these tests were found to be promising. The chemotactic effect of the Mg60Zn35Ca5 BMGC extraction medium on rabbit osteoblasts was demonstrated through a transwell migration assay. For the in vivo section of this study, a rabbit tendon-bone interference fixation model was established to determine the biocompatibility and osteogenic potential of Mg60Zn35Ca5 BMGC in a created bony tunnel for a period of up to 24 weeks. The results show that Mg60Zn35Ca5 BMGC induced considerable new bone formation at the implant site in comparison with conventional titanium alloy after 24 weeks of implantation. In conclusion, this study revealed that Mg60Zn35Ca5 BMGC demonstrated adequate biocompatibility and exhibited significant osteogenic potential both in vitro and in vivo. These advantages may be clinically beneficial to the development of Mg60Zn35Ca5 BMGC implants for future applications.


Assuntos
Materiais Biocompatíveis/química , Cálcio/química , Vidro/química , Magnésio/química , Nanopartículas Metálicas/química , Osteogênese/efeitos dos fármacos , Zinco/química , Animais , Materiais Biocompatíveis/farmacologia , Biomarcadores , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/metabolismo , Movimento Celular , Sobrevivência Celular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Imagem Tridimensional , Teste de Materiais , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Coelhos , Tendões , Microtomografia por Raio-X
14.
Nanoscale ; 11(18): 9163-9175, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31038150

RESUMO

Diabetes is a chronic metabolic disorder disease characterized by high blood glucose levels and has become one of the most serious threats to human health. In recent decades, a number of insulin delivery systems, including bulk gels, nanogels, and polymeric micelles, have been developed for the treatment of diabetes. Herein, a kind of glucose and H2O2 dual-responsive polymeric nanogel was designed for enhanced glucose-responsive insulin delivery. The polymeric nanogels composed of poly(ethylene glycol) and poly(cyclic phenylboronic ester) (glucose and H2O2 dual-sensitive groups) were synthesized by a one-pot thiol-ene click chemistry approach. The nanogels displayed glucose-responsive release of insulin and the release rate could be promoted by the incorporation of glucose oxidase (GOx), which generated H2O2 at high glucose levels and H2O2 further oxidizes and hydrolyzes the phenylboronic ester group. The nanogels have characteristics of long blood circulation time, a fast response to glucose, and excellent biocompatibility. Moreover, subcutaneous delivery of insulin to diabetic mice with the insulin/GOx-loaded nanogels presented an effective hypoglycemic effect compared to that of injection of insulin or insulin-loaded nanogels. This kind of nanogel would be a promising candidate for the delivery of insulin in the future.


Assuntos
Glucose Oxidase/química , Glucose/metabolismo , Peróxido de Hidrogênio/metabolismo , Hipoglicemiantes/metabolismo , Insulina/metabolismo , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Química Click , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Portadores de Fármacos/química , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Glucose/química , Glucose Oxidase/metabolismo , Teste de Tolerância a Glucose , Peróxido de Hidrogênio/química , Hipoglicemiantes/química , Hipoglicemiantes/uso terapêutico , Insulina/química , Insulina/uso terapêutico , Camundongos , Células NIH 3T3 , Polietilenoglicóis/toxicidade , Polietilenoimina/toxicidade
15.
Artif Cells Nanomed Biotechnol ; 47(1): 1693-1701, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31062610

RESUMO

Adipose tissue has the therapeutic capacity in the form of a fat graft, for example, for treatment of irradiation-induced scars and difficult to heal dermal wounds. For large-scale clinical application, an off-the-shelf product is warranted. In recent years, ECM-derived hydrogels are postulated to harbour therapeutic capacity and might even replicate the beneficial effects of adipose tissue. In normal homeostasis, the natural ECM acts as a deposit of growth factors, that releases them over time. In the healing of lesions, this might promote cell accumulation and proliferation which in turn stimulates angiogenesis and repair. The decellularization of tissue and the generation of hydrogels may leave cytotoxic traces. Therefore, our research assessed the cytotoxic effect of human adipose tissue-derived ECM hydrogels on connective tissue cells i.e. fibroblasts. The results showed no cytotoxicity, meaning the hydrogels caused no cell death. Cell migration and survival were observed when cultured in ECM hydrogels and followed for 7 days. Cell survival in the hydrogel was confirmed with CFDA staining and also cells showed the ability to penetrate and migrate throughout the gel. We conclude that ECM hydrogels are promising to use as innovative therapy for wound healing.


Assuntos
Tecido Adiposo/citologia , Materiais Biocompatíveis/farmacologia , Matriz Extracelular/metabolismo , Hidrogéis/farmacologia , Tecidos Suporte/química , Materiais Biocompatíveis/metabolismo , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Humanos , Hidrogéis/metabolismo , Miócitos de Músculo Liso/citologia , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Osteogênese/efeitos dos fármacos
16.
SAR QSAR Environ Res ; 30(5): 363-382, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31112078

RESUMO

In the current study, we have developed predictive quantitative structure-activity relationship (QSAR) models for cellular response (foetal rate lung fibroblast proliferation) and protein adsorption (fibrinogen adsorption (FA)) on the surface of tyrosine-derived biodegradable polymers designed for tissue engineering purpose using a dataset of 66 and 40 biodegradable polymers, respectively, employing two-dimensional molecular descriptors. Best four individual models have been selected for each of the endpoints. These models are developed using partial least squares regression with a unique combination of six and four descriptors for cellular response and protein adsorption, respectively. The generated models were strictly validated using internal and external metrics to determine the predictive ability and robustness of proposed models. Subsequently, the validated individual models for each response endpoints were used for the generation of 'intelligent' consensus models ( http://teqip.jdvu.ac.in/QSAR_Tools/DTCLab/ ) to improve the quality of predictions for the external data set. These models may help in prediction of virtual polymer libraries for rational design/optimization for properties relevant to biomedical applications prior to their synthesis.


Assuntos
Materiais Biocompatíveis/química , Fibrinogênio/química , Modelos Moleculares , Polímeros/química , Adsorção/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Fenômenos Fisiológicos Celulares/efeitos dos fármacos , Análise dos Mínimos Quadrados , Estrutura Molecular , Polímeros/farmacologia , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes
17.
Int J Mol Sci ; 20(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075984

RESUMO

PURPOSE: The objective of this study was to assess the influence of a novel surface of dental implants (ContacTi®) on the osseointegration process in a minipig model. The surface was compared with other existing surfaces on the market (SLA® and SLActive®) by employing bone implant contact analysis (BIC) and implant stability. METHOD: Twelve minipigs were used with prior authorisation from an ethics committee. Three types of surfaces were tested: SLA® (sand-blasted acid-etched titanium), SLActive® (same but hydrophilic, performed under a nitrogen atmosphere), and ContacTi® (alumina particle bombardment of titanium, bioactivated when treated thermochemically) in 4.1 mm × 8 mm implants with internal connection and a polished neck. Twelve implants of each surface type (N = 36) were placed, sacrificing 1/3 of the animals at 2 weeks of placement, 1/3 at 4 weeks and the remaining 1/3 at 8 weeks. Numerical variables were compared with Analysis of Variance, and the correlation between ISQ and BIC was established with the Spearman's rank correlation coefficient. RESULTS: SLActive® and ContacTi® surfaces showed elevated osteoconductivity at 4 weeks, maintaining a similar evolution at 8 weeks (large amount of mature lamellar tissue with high maturity and bone quality). The SLA® surface showed slower maturation. The ISQ values in surgery were elevated (above 65), higher at necropsy and higher at 4 and 8 weeks in the SLA® group than in the other two (SLActive® and ContacTi®). No significant correlation was found between ISQ and BIC for each implant surface and necropsy time. CONCLUSION: The three surfaces analysed showed high RFA and BIC values, which were more favourable for the SLActive® and ContacTi® surfaces. No statistical correlation was found between the RFA and BIC values in any of the three surfaces analysed.


Assuntos
Materiais Biocompatíveis/farmacologia , Implantes Dentários , Osseointegração , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Feminino , Osseointegração/efeitos dos fármacos , Propriedades de Superfície , Suínos , Porco Miniatura
18.
Yonsei Med J ; 60(5): 429-439, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31016904

RESUMO

PURPOSE: To explore the effects of biodegradable magnesium alloy stents (BMAS) on remodeling of vein graft (VG) anastomotic restenosis. MATERIALS AND METHODS: To establish a VG restenosis model, seventy two New Zealand rabbits were randomly divided into three groups according to whether a stent was implanted in the graft vein or not. BMASs and 316L stainless steel stents were implanted in BMAS and 316L groups, respectively, while no stent was implanted in the no-treatment control group (NC group). Loss of lumen diameter in the graft vein was measured in all three groups. Upon harvesting VG segments to evaluate intimal proliferation and re-endothelization, the degradation and biological safety of the stents were observed to explore the effects of BMAS on VG remodeling. RESULTS: Model establishment and stent implantation were successful. The BMAS reduced lumen loss, compared with the control group (0.05±0.34 mm vs. 0.90±0.39 mm, p=0.001), in the early stage. The neointimal area was smaller in the BMAS group than the 316L group after 4 months (4.96±0.66 mm² vs. 6.80±0.69 mm², p=0.017). Re-endothelialization in the BMAS group was better than that in the 316L group (p=0.001). Within 4 months, the BMAS had degraded, and the magnesium was converted to phosphorus and calcium. The support force of the BMAS began to reduce at 2-3 months after implantation, without significant toxic effects. CONCLUSION: BMAS promotes positive remodeling of VG anastomosis and has advantages over the conventional 316L stents in the treatment of venous diseases.


Assuntos
Ligas/farmacologia , Materiais Biocompatíveis/farmacologia , Prótese Vascular , Reestenose Coronária/terapia , Magnésio/farmacologia , Stents , Animais , Implante de Prótese Vascular , Constrição Patológica , Reestenose Coronária/complicações , Feminino , Neointima/complicações , Coelhos
19.
J Basic Microbiol ; 59(6): 569-578, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30980727

RESUMO

The biocompatible-coated iron oxide nanoparticles (IONs) have attracted a great interest because of their various applications in biological science and medicine. In most cases, the toxic effect of naked iron oxide nanoparticles is completely cleared by adding a biocompatible coating, such as polysaccharides, polyethylene glycol (PEG), or biosynthesis of biocompatible-coated IONs using microorganisms such as bacteria. In the present study, polysaccharide-coated iron oxide nanoparticles were produced by a strain of Staphylococcus warneri isolated from a thermal spring. For identification of the isolated bacterium, 16S rRNA gene sequencing was done. Characterization of the nanoparticles was performed for the first time, using transmission electron microscopy (TEM), dynamic light scattering (DLS), thermogravimetric analysis (TGA), X-ray crystallography (XRD), Fourier-transform infrared (FTIR) spectroscopy, vibrating sample magnetometer (VSM), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results indicated that the spherical iron oxide nanoparticles were coated by a polysaccharide (13.6%), which provided a large negative charge of -91 mV and very low saturation magnetization of around 0.28 emu/g. The result of MTT assay on MOLT-4 cell lines showed that the percentage of viability was between 95.6% and 68.9% in the 10-100 µM of nanoparticle concentrations with a high IC 50 value, which makes it appropriate for biomedical applications such as cancer therapy.


Assuntos
Materiais Biocompatíveis/química , Fontes Termais/microbiologia , Nanopartículas de Magnetita/química , Polissacarídeos Bacterianos/química , Staphylococcus/metabolismo , Materiais Biocompatíveis/isolamento & purificação , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Campos Magnéticos , Nanopartículas de Magnetita/ultraestrutura , Tamanho da Partícula , Polissacarídeos Bacterianos/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Staphylococcus/classificação , Staphylococcus/genética , Staphylococcus/isolamento & purificação
20.
Chem Commun (Camb) ; 55(37): 5359-5362, 2019 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30994651

RESUMO

Herein, we have fabricated gold nanorod graphitic nanocapsule (AuNR@G) doped poly(vinyl alcohol) (PVA)/chitosan (CS) hydrogels, which possessed highly efficient and stable photothermal antibacterial properties for both Gram-negative E. coli and Gram-positive S. aureus under the irradiation of a near-infrared laser.


Assuntos
Ouro/química , Hidrogéis/química , Raios Infravermelhos , Nanocápsulas/química , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Quitosana/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/efeitos da radiação , Humanos , Hidrogéis/farmacologia , Álcool de Polivinil/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/efeitos da radiação
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