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1.
Carbohydr Polym ; 334: 122017, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38553216

RESUMO

Over the last decade, the convergence of advanced materials and innovative applications has fostered notable scientific progress within the biomedical and pharmaceutical fields. Porphyrins and their derivatives, distinguished by an extended conjugated π-electron system, have a relevant role in propelling these advancements, especially in drug delivery systems, photodynamic therapy, wound healing, and (bio)sensing. However, despite their promise, the practical clinical application of these macrocycles is hindered by their inherent challenges of low solubility and instability under physiological conditions. To address this limitation, researchers have exploited the synergistic association of porphyrins and chlorins with polysaccharides by engineering conjugated systems and composite/hybrid materials. This review compiles the principal advances in this growing research field, elucidating fundamental principles and critically examining the applications of such materials within biomedical and pharmaceutical contexts. Additionally, the review addresses the eventual challenges and outlines future perspectives for this poignant research field. It is expected that this review will serve as a comprehensive guide for students and researchers dedicated to exploring state-of-the-art materials for contemporary medicine and pharmaceutical applications.


Assuntos
Polissacarídeos , Porfirinas , Humanos , Preparações Farmacêuticas , Sistemas de Liberação de Medicamentos , Materiais Biocompatíveis
2.
J Mater Sci Mater Med ; 35(1): 14, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38353746

RESUMO

In this study, poly (lactic-co-glycolic acid) (PLGA) microparticles loaded with cannabidiol (CBD) were synthesized (PLGA@CBD microparticles) and embedded up to 10 wt% in a chondroitin sulfate/polyvinyl alcohol hydrogel matrix. In vitro chemical, physical, and biological assays were carried out to validate the potential use of the modified hydrogels as biomaterials. The microparticles had spherical morphology and a narrow range of size distribution. CBD encapsulation efficiency was around 52%, loading was approximately 50%. Microparticle addition to the hydrogels caused minor changes in their morphology, FTIR and thermal analyses confirmed these changes. Swelling degree and total porosity were reduced in the presence of microparticles, but similar hydrophilic and degradation in phosphate buffer solution behaviors were observed by all hydrogels. Rupture force and maximum strain at rupture were higher in the modified hydrogels, whereas modulus of elasticity was similar across all materials. Viability of primary human dental pulp cells up to 21 days was generally not influenced by the addition of PLGA@CBD microparticles. The control hydrogel showed no antimicrobial activity against Staphylococcus aureus, whereas hydrogels with 5% and 10% PLGA@CBD microparticles showed inhibition zones. In conclusion, the PLGA@CBD microparticles were fabricated and successfully embedded in a hydrogel matrix. Despite the hydrophobic nature of CBD, the physicochemical and morphological properties were generally similar for the hydrogels with and without the CBD-loaded microparticles. The data reported in this study suggested that this original biomaterial loaded with CBD oil has characteristics that could enable it to be used as a scaffold for tissue/cellular regeneration.


Assuntos
Canabidiol , Humanos , Porosidade , Materiais Biocompatíveis , Bioensaio , Hidrogéis
3.
Braz. j. otorhinolaryngol. (Impr.) ; 88(3): 331-336, May-June 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1384179

RESUMO

Abstract Introduction The association between the intensity of obstructive sleep apnea and skeletal alterations in the face and hyoid bone is still scarcely addressed in the literature. Objective To evaluate whether the intensity of obstructive sleep apnea is associated with craniofacial alterations and the position of the hyoid bone in children with mixed dentition. Methods 76 children aged 7 to 10 years old were examined by otorhinolaryngological evaluation, polysomnography, and orthodontic assessment, including cephalometry. The participants were divided in 3 groups: primary snoring, mild obstructive sleep apnea and moderate to severe obstructive sleep apnea. Cephalometric measures of the face and hyoid bone were assessed. These measures were compared among the different groups by unpaired Student's t test. Moreover, these measures were correlated with the patient's obstructive apnea and hypopnea index variable using Pearson's correlation test. Results Of the 76 children, 14 belonged to group 1, with primary snoring; 46 to group 2, with mild obstructive sleep apnea; and 16 to group 3, with moderate-severe obstructive sleep apnea. There was no difference between the groups regarding the craniofacial variables. Children with obstructive sleep apnea showed a longer distance from the hyoid bone to the mandibular plane when compared to the primary snoring group (p < 0.05). Between the two obstructive sleep apnea subgroups, patients with moderate or severe disease showed significantly shorter horizontal distance between the hyoid bone and the posterior pharyngeal wall (p < 0.05), when compared to the groups with mild obstructive sleep apnea. We also observed a significant positive correlation between obstructive apnea and hypopnea index and the distance from the hyoid to the mandibular plane (p < 0.05) as well as a significant negative association between obstructive apnea and hypopnea index and the horizontal distance from the hyoid to the posterior pharyngeal wall (p < 0.01). Conclusion We did not observe any association between obstructive sleep apnea and linear lateral alterations of the face. In contrast, there is a direct association between obstructive sleep apnea severity and the inferior and posterior position of the hyoid bone in children aged 7 to 10 years old.


Resumo Introdução A relação entre a intensidade da apneia obstrutiva do sono e alterações esqueléticas da face e do hioide em crianças é pouco explorada na literatura. Objetivo Avaliar se a intensidade da apneia obstrutiva do sono correlaciona-se às alterações craniofaciais e ao posicionamento do osso hioide em crianças em fase de dentição mista. Método Foram submetidas 76 crianças entre 7 e 10 anos à avaliação otorrinolaringológica, polissonografia e avaliação ortodôntica, inclusive cefalometria. Os participantes foram divididos em 3 grupos: grupo 1 com ronco primário, grupo 2 com apneia obstrutiva do sono leve e grupo 3 com apneia obstrutiva do sono moderada/grave. Foram analisadas medidas cefalométricas da face e do osso hioide. Essas medidas foram comparadas entre si dentro dos diferentes grupos por teste t de Student não pareado. Além disso, essas medidas foram correlacionadas com a variável índice de apneias obstrutivas e hipopneias do paciente através do teste de correlação de Pearson. Resultados Das 76 crianças, 14 constituíram o grupo 1, ronco primário; 46 o grupo 2, apneia obstrutiva do sono leve; e 16 o grupo 3, apneia obstrutiva do sono moderada/grave. Não se observou diferença significante entre os grupos para as variáveis craniofaciais. Observou-se maior distância do osso hioide ao plano mandibular nos dois grupos com apneia obstrutiva do sono quando comparado ao ronco primário (p < 0,05). Entre os dois subgrupos da apneia obstrutiva do sono, os pacientes com doença moderada ou grave apresentaram distância horizontal entre o hioide e a parede posterior da faringe significantemente menor (p < 0,05), quando comparados aos grupos com apneia obstrutiva do sono leve. Observamos ainda correlação significantemente positiva entre índice de apneias obstrutivas e hipopneias e a distância do hioide ao plano mandibular (p < 0,05) e significantemente negativa entre índice de apneias obstrutivas e hipopneias e distância horizontal do hioide com a parede posterior da faringe (p < 0,01). Conclusão Não observamos relação da apneia obstrutiva do sono com alterações lineares laterais da face. Em contraste, existe relação direta entre a gravidade da apneia obstrutiva do sono e a posição inferior e posterior do osso hioide em crianças entre 7 e 10 anos.

4.
Braz J Otorhinolaryngol ; 88(3): 331-336, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-32819863

RESUMO

INTRODUCTION: The association between the intensity of obstructive sleep apnea and skeletal alterations in the face and hyoid bone is still scarcely addressed in the literature. OBJECTIVE: To evaluate whether the intensity of obstructive sleep apnea is associated with craniofacial alterations and the position of the hyoid bone in children with mixed dentition. METHODS: 76 children aged 7 to 10 years old were examined by otorhinolaryngological evaluation, polysomnography, and orthodontic assessment, including cephalometry. The participants were divided in 3 groups: primary snoring, mild obstructive sleep apnea and moderate to severe obstructive sleep apnea. Cephalometric measures of the face and hyoid bone were assessed. These measures were compared among the different groups by unpaired Student's t test. Moreover, these measures were correlated with the patient's obstructive apnea and hypopnea index variable using Pearson's correlation test. RESULTS: Of the 76 children, 14 belonged to group 1, with primary snoring; 46 to group 2, with mild obstructive sleep apnea; and 16 to group 3, with moderate-severe obstructive sleep apnea. There was no difference between the groups regarding the craniofacial variables. Children with obstructive sleep apnea showed a longer distance from the hyoid bone to the mandibular plane when compared to the primary snoring group (p<0.05). Between the two obstructive sleep apnea subgroups, patients with moderate or severe disease showed significantly shorter horizontal distance between the hyoid bone and the posterior pharyngeal wall (p<0.05), when compared to the groups with mild obstructive sleep apnea. We also observed a significant positive correlation between obstructive apnea and hypopnea index and the distance from the hyoid to the mandibular plane (p<0.05) as well as a significant negative association between obstructive apnea and hypopnea index and the horizontal distance from the hyoid to the posterior pharyngeal wall (p<0.01). CONCLUSION: We did not observe any association between obstructive sleep apnea and linear lateral alterations of the face. In contrast, there is a direct association between obstructive sleep apnea severity and the inferior and posterior position of the hyoid bone in children aged 7 to 10 years old.


Assuntos
Obstrução das Vias Respiratórias , Apneia Obstrutiva do Sono , Cefalometria , Criança , Humanos , Osso Hioide/diagnóstico por imagem , Polissonografia , Apneia Obstrutiva do Sono/diagnóstico por imagem , Ronco
5.
Carbohydr Polym ; 265: 118013, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33966820

RESUMO

This study reports the preparation of microspheres of pectin and magnetite nanoparticles coated by chitosan to encapsulate and deliver drugs. Magnetic-pectin microspheres were obtained by ionotropic gelation followed by polyelectrolyte complexation with chitosan. Characterization data show that magnetite changes the physicochemical and morphological properties of the microspheres compared to the non-magnetic samples. Using metamizole (Mtz) as a drug model, the magnetic microspheres showed appreciable encapsulation efficiency (85 %). Release experiments performed in simulated gastric (pH 1.2) and intestinal (pH 6.8) fluids suggested that the release process is pH-dependent. At pH 6.8, the Mtz release is favored achieving 75 % after 12 h. The application of an external magnetic field increased the release to 91 % at pH 6.8, indicating that the release also is magnetic-dependent. The results suggest that the magnetic microspheres based on pectin/chitosan biopolymers show the potential to be used as a multi-responsive drug delivery system.


Assuntos
Quitosana/química , Dipirona/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas de Magnetita/química , Microesferas , Pectinas/química , Animais , Biopolímeros/química , Citrus sinensis/química , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos , Conteúdo Gastrointestinal/química , Géis/química , Humanos , Concentração de Íons de Hidrogênio , Campos Magnéticos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos
6.
J Biomed Mater Res A ; 109(7): 1160-1172, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-32985092

RESUMO

Novel poly(vinyl alcohol)/chondroitin sulfate (PVA/CS) composite hydrogels containing hydroxyapatite (HA) or Sr-doped HA (HASr) particles were synthesized by a freeze/thaw method and characterized aiming towards biomedical applications. HA and HASr were synthesized by a wet-precipitation method and added to the composite hydrogels in fractions up to 15 wt%. Physical-chemical characterizations of particles and hydrogels included scanning electron microscopy, energy-dispersive spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetry, porosity, compressive strength/elastic modulus, swelling degree, and cell viability. Particles were irregular in shape and appeared to have narrow size variation. The thermal behavior of composite hydrogels was altered compared to the control (bare) hydrogel. All hydrogels exhibited high porosity. HA/HASr particles reduced total porosity without reducing pore size. The mechanical strength was improved as the fraction of HA or HASr was increased. HASr particles led to a faster water uptake but did not interfere with the total hydrogel swelling capacity. In cell viability essay, increased cell growth (above 120%) was observed in all groups including the control hydrogel, suggesting a bioactive effect. In conclusion, PVA/CS hydrogels containing HA or HASr particles were successfully synthesized and showed promising morphological, mechanical, and swelling properties, which are particularly required for scaffolding.


Assuntos
Materiais Biocompatíveis/química , Sulfatos de Condroitina/química , Durapatita/química , Álcool de Polivinil/química , Estrôncio/química , Materiais Biocompatíveis/síntese química , Sulfatos de Condroitina/síntese química , Força Compressiva , Durapatita/síntese química , Módulo de Elasticidade , Álcool de Polivinil/síntese química , Porosidade , Termogravimetria
7.
J Pharm Pharmacol ; 70(12): 1723-1732, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30251258

RESUMO

OBJECTIVES: A microemulsion-based delivery system was designed to improve vitamin E (VE) properties, and its antinociceptive, antioxidant, antidepressant- and anxiolytic-like activities in mice were evaluated. METHODS: Male Swiss mice received, by intragastric route, canola oil (20 ml/kg), blank microemulsion (B-ME) (20 ml/kg), VE free (VE-F) (200 mg/kg) or VE microemulsion (VE-ME) (200 mg/kg). In acute treatment, a single dose of treatments was administrated and 30 min after behavioural tests were performed. In the subchronic treatment, mice received such treatments, once a day, for 8 days. On the eighth day, behavioural tests were performed. KEY FINDINGS: In the subchronic treatment, VE-ME increased entries and spent time in the open arms in the elevated plus-maze test and decreased the immobility time in the tail suspension test, but no change was found after acute treatment. Acute and subchronic treatments with VE-ME increased response latency to thermal stimulus in the hot-plate test. VE-ME decreased the thiobarbituric acid reactive species levels in the acute and subchronic protocols. Additionally, in subchronic treatment, VE-ME increased renal catalase activity, but VE-F reduced its activity. CONCLUSIONS: Vitamin E-microemulsions showed antioxidant, antinociceptive, antidepressant- and anxiolytic-like actions; thus, ME-based delivery improved pharmacological properties of VE.


Assuntos
Analgésicos/farmacologia , Ansiolíticos/farmacologia , Antidepressivos/farmacologia , Antioxidantes/farmacologia , Sistemas de Liberação de Medicamentos , Vitamina E/farmacologia , Analgésicos/administração & dosagem , Animais , Ansiolíticos/administração & dosagem , Antidepressivos/administração & dosagem , Antioxidantes/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Emulsões , Masculino , Camundongos , Vitamina E/administração & dosagem
8.
Mater Sci Eng C Mater Biol Appl ; 84: 90-98, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29519447

RESUMO

This study investigated the main effects of the oral treatment with 7-chloro-4-phenylselanyl quinoline (4-PSQ) on symptoms, inflammatory and oxidative parameters in an atopic dermatitis (AD) model in BALB/c mice. In addition, the possibility of antioxidant property of 4-PSQ improves the potential of a biofilm (based on chitosan/poly(vinyl alcohol) (PVA)/ bovine bone powder (BBP)) for the treatment of AD-like skin lesions was evaluated. 2,4-Dinitrochlorobenzene (DNCB) was applied to the dorsal skin on days 1-3 for sensitization. Mice were challenged with DNCB on the ear (on days 14-29) and dorsal skin (on days 14, 17, 20, 23, 26, and 29) and treated with 4-PSQ, dexamethasone, biofilm (biofilm sample without 4-PSQ) or 4-PSQ-loaded biofilms. On the day 30, skin severity scores and scratching behavior were determined. After that, animals were sacrificed, and ears and dorsal skin were removed for determination of inflammatory and oxidative parameters. DNCB induced the skin lesions, scratching behavior and ear swelling, increased myeloperoxidase (MPO) activity (ear and back) and reactive species (RS) levels (back). 4-PSQ, 4-PSQ-loaded biofilms and biofilm treatments ameliorated skin severity scores, scratching behavior and inflammatory response induced by DNCB. 4-PSQ and 4-PSQ-loaded biofilm treatments partially protected against the increase in the RS levels induced by DNCB. Our results revealed that the incorporation of 4-PSQ improved the therapeutic effect of the biofilm. The efficacy of 4-PSQ in treating AD-like lesions was similar or better than dexamethasone. In summary, 4-PSQ has a potential therapeutic advantage in the treatment and management of AD.


Assuntos
Anti-Inflamatórios/farmacologia , Quinolinas/química , Quinolinas/farmacologia , Pele/efeitos dos fármacos , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Antioxidantes/química , Antioxidantes/metabolismo , Comportamento Animal/efeitos dos fármacos , Dermatite Atópica/tratamento farmacológico , Dermatite Atópica/patologia , Dexametasona/farmacologia , Dexametasona/uso terapêutico , Dinitroclorobenzeno/química , Dinitroclorobenzeno/toxicidade , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/metabolismo , Quinolinas/uso terapêutico , Espécies Reativas de Oxigênio/metabolismo , Índice de Gravidade de Doença , Pele/metabolismo , Pele/patologia , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Carbohydr Polym ; 161: 187-196, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28189228

RESUMO

In this study, copper nanoparticles (CuNPs) were synthesized and stabilized into a chitosan/poly(vinyl alcohol) (CP) based film using a simple protocol under mild conditions. The polymeric matrix utilized in this study allows synthesizing stable nanoparticle with narrow size distribution within the film matrix. Further, this system showed very attractive properties, such as good mechanical properties, chemical resistance, easy handling during use and recovery, relatively low-cost as compared to other similar systems, among others. The catalytic performance of CP-Cu film was tested in the reduction reaction of nitrobenzene (NB) to aniline (AN). Our findings reveal that CP-Cu film catalyzes the reaction efficiently and also decreases the energy of activation (Ea) as compared to other catalysts. The catalytic efficiency of CP-Cu regarding this reaction was kept even after 6 consecutive reuse cycles. All these results rank this novel system as a promising catalyst in the reduction of aromatic nitro compounds to aromatic amines.


Assuntos
Quitosana/química , Cobre/química , Nanopartículas/química , Nitrocompostos/química , Catálise
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