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1.
Int J Mol Sci ; 24(6)2023 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-36982196

RESUMO

Many activities have been described for propolis, including, antiviral, antibacterial, antifungal, anti-inflammatory, immunoregulatory, antioxidant and wound healing properties. Recently, propolis has been highlighted due to its potential application in the pharmaceutical and cosmetic industries, motivating a better understanding of its antioxidant and anti-inflammatory activities. Propolis and its main polyphenolic compounds presented high antioxidant activity, and effectiveness as broad spectrum UVB and UVA photoprotection sunscreens. Through a qualitative phytochemical screening, the ethanolic red propolis extracts (EEPV) (70% at room temperature and 70% at a hot temperature) presented a positive result for flavonoids and terpenoids. It presented an antioxidant activity for reducing 50% of DPPH of 17 and 12 µg/mL for extraction at room temperature and at a hot temperature, respectively. The UPLC-QTOF-MS/MS analysis allowed the annotation of 40 substances for EEPV-Heated and 42 substances for EEPV-Room Temperature. The IC50 results of the ABTS scavenging activity was 4.7 µg/mL for both extractions, at room temperature and at a hot temperature. Additionally, we also evaluated the cytotoxic profile of propolis extracts against macrophage (RAW 264.7 cells) and keratinocytes (HaCaT cells), which showed non-cytotoxic doses in cell viability assays even after a long period of exposure. In addition, propolis extracts showed antibacterial activity for Gram-positive bacteria (Staphylococcus aureus and Staphylococcus epidermidis), demonstrating potential biological activity for the creation of formulations aimed at disease control and prevention.


Assuntos
Anti-Infecciosos , Ascomicetos , Própole , Própole/farmacologia , Própole/química , Antioxidantes/farmacologia , Antioxidantes/química , Protetores Solares/farmacologia , Espectrometria de Massas em Tandem , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Extratos Vegetais/farmacologia , Extratos Vegetais/química
2.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203662

RESUMO

Cancer is one of the deadliest diseases worldwide and has been responsible for millions of deaths. However, developing a satisfactory smart multifunctional material combining different strategies to kill cancer cells poses a challenge. This work aims at filling this gap by developing a composite material for cancer treatment through hyperthermia and drug release. With this purpose, magnetic nanoparticles were coated with a polymer matrix consisting of poly (L-co-D,L lactic acid-co-trimethylene carbonate) and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer. High-resolution transmission electron microscopy and selected area electron diffraction confirmed magnetite to be the only iron oxide in the sample. Cytotoxicity and heat release assays on the hybrid nanoparticles were performed here for the first time. The heat induction results indicate that these new magnetic hybrid nanoparticles are capable of increasing the temperature by more than 5 °C, the minimal temperature rise required for being effectively used in hyperthermia treatments. The biocompatibility assays conducted under different concentrations, in the presence and in the absence of an external alternating current magnetic field, did not reveal any cytotoxicity. Therefore, the overall results indicate that the investigated hybrid nanoparticles have a great potential to be used as carrier systems for cancer treatment by hyperthermia.


Assuntos
Calefação , Hipertermia Induzida , Humanos , Hipertermia , Eletricidade
3.
J Tissue Eng Regen Med ; 13(9): 1651-1663, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31218837

RESUMO

Bioactive glass has been proved to have many applications in bioengineering due to its bone regenerative properties. In this work, an innovative, highly resorbable bioactive glass containing 90% SiO2 (BG90) to be used as a bone substitute was developed. The BG90 was synthetized by the sol-gel process with the dry step at room temperature. The biomaterial showed in vitro and in vivo bioactivities even with silica content up to 90%. Moreover, the BG90 presented high porosity and surface area due to its homogenously interconnected porous network. In vitro, it was observed to have high cell viability and marked osteoblastic differentiation of rat bone marrow-derived cells when in contact with BG90 ion extracts. The BG90 transplantation into rat tibia defects was analysed at 1, 2, 3, 4, 7, and 10 weeks post-operatively and compared with the defects of negative (no graft) and positive (autogenous bone graft) controls. After 4 weeks of grafting, the BG90 was totally resorbed and induced higher bone formation than did the positive control. Bone morphogenetic protein 2 (BMP-2) expression at the grafting site peaked at 1 week and decreased similarly after 7 weeks for all groups. Only the BG90 group was still exhibiting BMP-2 expression in the last experimental time. Our data demonstrated that the BG90 could be an attractive candidate to provide useful approaches in hard-tissue bioengineering.


Assuntos
Cerâmica/farmacologia , Dióxido de Silício/farmacologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/farmacologia , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2/metabolismo , Remodelação Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Durapatita/farmacologia , Células Gigantes/citologia , Células Gigantes/efeitos dos fármacos , Inflamação/patologia , Masculino , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Wistar , Tíbia/efeitos dos fármacos , Tíbia/fisiologia
4.
Curr Pharm Des ; 21(37): 5417-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26377654

RESUMO

Superparamagnetic iron oxides, as magnetite (Fe3O4) or maghemite (γ-Fe2O3), are primary materials with intrinsic properties that enable them, as single components or as special composites, to base advanced techniques in medical clinical practices, as a contrast agent in magnetic resonance imaging (MRI), as magnetically-induced hyperthermic heat generator, and as a magnetic guide to locally deliver drugs to specific sites in the human body. An interesting approach to developing nanoplatforms for those applications consists in manufacturing core@shell nanostructures, in which the precursor magnetic iron oxide (usually, magnetite) acts as a core, and an organic, or inorganic compound is used as a shell in a multifunctional composite. In this review, we report the current advances in the use of magnetite-based core@shell nanostructures, including Fe3O4@SiO2 and Fe3O4@polymers, in MRI, magnetic hyperthermia and drug delivery systems for diagnosis and therapy of tumor cells. The development of nanoplatforms for combined therapy and diagnostic (theranostic) is also addressed.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas de Magnetita/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Compostos Férricos/administração & dosagem , Compostos Férricos/química , Óxido Ferroso-Férrico/administração & dosagem , Óxido Ferroso-Férrico/química , Humanos , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/administração & dosagem , Tamanho da Partícula
5.
Rev. bras. anal. clin ; 27(2): 47-50, 1995. tab
Artigo em Português | LILACS | ID: lil-269357

RESUMO

Os bloqueadores beta-adrenérgicos (BBA) säo fármacos amplamente utilizados no tratamento de algumas doenças cardiovasculares, sendo empregados, também, na ingestäo intencional de superdose, de forma isolada ou em associaçäo com outros farmacos, com a finalidade de cometer suicídio. Em nosso meio tal fato é de crescente importância. O atenolol (A), Metoprolol (M), Nadolol (N), Pindolol (Pi) e Propranolol (Pr) säo os BBA comercializados no Brasil. Com a finalidade de determinar esses BBA em material biológico, nos últimos anos, foram estabelecidas algumas metodologias analíticas. Na determinaçäo de pequenas concentraçöes (ng/m), têm sido utilizadas técnicas cromatográficas mais sofisticadas. A cromatografia em camada delgada (CCD), além de custo inferior e fácil manipulaçäo, em relaçäo a outras técnicas cromatográficas, näo necessitando de pessoal qualificado, tem sua eficiência comprovada após o uso de doses terapêuticas e subterapêuticas. O objetivo do nosso trabalho foi desenvolver uma técnica para identificaçäo dos BBA estudados, tanto para o laboratório de análises toxicológicas, quanto para laboratórios de análises clínicas, em regiöes onde näo existam laboratórios de toxicologia...


Assuntos
Humanos , Antagonistas Adrenérgicos beta/farmacologia , Intoxicação/diagnóstico , Toxicologia , Urina , Cromatografia em Camada Fina
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