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1.
Artigo em Português | LILACS-Express | LILACS | ID: biblio-1551116

RESUMO

Introdução: a própolis é uma composição resinosa produzida por abelhas e utilizada em suas colmeias contra microrganismos. Existem diversos tipos desse composto, sendo o de coloração vermelha o último espécime relatado na literatura. Assim, dentre suas aplicabilidades, a atividade antifúngica da própolis vermelha tem sido explorada com vistas a ampliar sua ação terapêutica. Objetivo: explorar estudos acerca da ação antifúngica da própolis vermelha, identificando suas potencialidades e desafios. Metodologia: foi realizada uma revisão integrativa nas bases de dados bibliográficos MEDLINE (via PubMed), SciELO e Google Acadêmico, complementada por uma diligência nas bases de ensaios clínicos ReBEC e Clinical Trials. Em seguida todos os estudos selecionados foram explorados para obtenção do cenário atual sobre o tema. Resultados: foram incluídos 08 estudos, sendo 01 deles um ensaio clínico. Os estudos comprovam a ação antifúngica da própolis vermelha, principalmente contra Candida spp. e Paracoccidioides brasiliensis, e evidenciam a maior potência fungicida deste composto em detrimento de outros tipos de própolis. Conclusão: a ação antifúngica da própolis vermelha mostra-se uma potencialidade em diversos estudos. Entretanto, o volume de pesquisas científicas relativas a esse tema é insuficiente e a complexidade desse composto configura-se como um desafio à sua aplicabilidade.


Introduction: propolis is a resinous composition produced by compounds and used in their hives against microorganisms. There are several types of this compound, the red one is the last specimen reported in the literature. Thus, among its applicability, the antifungal activity of red propolis has been explored as a path to expand its therapeutic action. Objective: to explore studies about the antifungal action of red propolis, identifying its potentialities and challenges. Methodology: Na integrative review was carried out in the bibliographic databases MEDLINE (via PubMed), SciELO and Google Scholar, complemented by a diligence in ReBEC and Clinical Trials databases. Then, all selected studies were explorers to obtain the current scenario on the subject. Results: 08 studies were included, which 01 of them was a clinical trial. Studies prove the antifungal action of red propolis, mainly against Candida spp. and Paracoccidioides brasiliensis, and show the greater fungicidal power of this compound compared to other types of propolis. Conclusion: the antifungal action of red propolis shows potential in several studies. However, the volume of scientific research on this theme is insufficient and the complexity of this compound represents a challenge to its applicability.


Introducción: el propóleo es una composición resinosa producida por las abejas y utilizada en sus colmenas contra los microorganismos. Existen varios tipos de este compuesto, siendo el rojo el último ejemplar reportado en la literatura. Así, entre sus posibilidades de aplicación, se ha explorado la actividad antifúngica del propóleo rojo con vistas a ampliar su acción terapéutica. Objetivo: explorar estudios sobre la acción antifúngica del propóleo rojo, identificando sus potencialidades y desafíos. Metodología: Se realizó una revisión en las bases de datos bibliográficas MEDLINE (vía PubMed), SciELO y Google Scholar, complementada con una diligencia en las bases de datos de ensayos clínicos ReBEC y Clinical Trials. Luego se exploraron todos los estudios seleccionados para obtener el escenario actual sobre el tema. Resultados: Se incluyeron 08 estudios, 01 de los cuales fue un ensayo clínico. Los estudios demuestran la acción antifúngica del propóleo rojo, principalmente contra Candida spp. y Paracoccidioides brasiliensis, y muestran el mayor poder fungicida de este compuesto en detrimento de otros tipos de propóleos. Conclusión: la acción antifúngica del propóleo rojo muestra potencial en varios estudios. Sin embargo, el volumen de investigación científica sobre este tema es insuficiente y la complejidad de este compuesto representa un desafío para su aplicabilidad.

2.
Braz. J. Pharm. Sci. (Online) ; 58: e20205, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1403727

RESUMO

Abstract Several factors contribute to the resistance of some pathogenic microorganisms and this fact requires the search for new therapeutic alternatives. The genus Cyperus (family Cyperaceae) groups species that present chemical compounds of pharmacological interest, mainly with antimicrobial action. Thus, the present work was carried out to investigate the antimicrobial activities, antioxidants and the phytochemical profile of Cyperus articulatus L. and Cyperus iria L. Hydroalcoholic extracts (1:1, v:v) of the aerial and underground parts of these species were used to analyze the total phenol content and to evaluate the in vitro antioxidant activity against the DPPH (2,2-diphenyl-1-picrylhydrazyl). The ethyl acetate and chloroform phases resulting from liquid-liquid partitioning of C. articulatus and C. iria extracts were evaluated in antimicrobial assays and subject to high performance liquid chromatography (HPLC-DAD) analysis. The chromatograms obtained by HPLC-DAD allowed us to identify four compounds: chlorogenic acid, catechin, quercetin, and quercitrin. The hydroalcoholic extracts of C. articulatus and C. iria showed a weak antioxidant activity with IC50 of 395.57 and 321.33 µg/mL (aerial parts), and 1,114.01 and 436.82 µg/mL (underground parts), respectively. Regarding antimicrobial activity, the chloroform phase of C. iria showed the best result at the concentration of only 31.2 µg/mL against the pathogens Candida albicans and Staphylococcus aureus. The ethyl acetate phases of the aerial parts of C. articulatus and C. iria did not show antimicrobial activity


Assuntos
Cyperaceae/classificação , Cyperus/efeitos adversos , Compostos Fitoquímicos , Anti-Infecciosos/análise , Antioxidantes/análise , Plantas Medicinais/efeitos adversos , Candida albicans , Cromatografia Líquida de Alta Pressão/métodos , Concentração Inibidora 50
3.
Braz Oral Res ; 35: e104, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34816893

RESUMO

This study aims to develop a nano-sized fluoridated layered double hydroxide (LDH)-based release system via hydrothermal treatment for the controlled delivery of fluoride (F-) ions in the oral environment. The synthesis of conventional LDH-type (C-LDH) precursor nanomaterials was conducted using a co-precipitation method at constant pH, and the nanoparticulate-LDH (N-LDH) was synthesized by a hydrothermal procedure. Fluoride LDH (F-LDH) products were obtained through indirect synthesis using the precursor ion-exchange technique by varying the agitation time (2 and 24 h) and temperature (25 and 40 °C) to produce 12 material samples. The materials were characterized by energy dispersive x-ray, hexamethyldisilazane, digital radiography x-ray, Fourier-transform infrared, thermogravimetric analysis, and scanning electron microscopy. Additionally, the F-release kinetic profile was evaluated for 21 d in neutral and acid media with mathematical model analysis. Products with varying F-quantities were obtained, revealing specific release profiles. In general, there was a higher F-release in the acid medium, with emphasis on F-LDH-8. Fluoride-LDH and controlled fluoride delivery was successfully obtained, proving the potential of these nanomaterials as alternative anti-caries agents.


Assuntos
Cárie Dentária , Fluoretos , Cariostáticos , Humanos , Hidróxidos , Radiografia Dentária Digital
4.
Braz. oral res. (Online) ; 35: e104, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS, BBO - Odontologia | ID: biblio-1350369

RESUMO

Abstract This study aims to develop a nano-sized fluoridated layered double hydroxide (LDH)-based release system via hydrothermal treatment for the controlled delivery of fluoride (F-) ions in the oral environment. The synthesis of conventional LDH-type (C-LDH) precursor nanomaterials was conducted using a co-precipitation method at constant pH, and the nanoparticulate-LDH (N-LDH) was synthesized by a hydrothermal procedure. Fluoride LDH (F-LDH) products were obtained through indirect synthesis using the precursor ion-exchange technique by varying the agitation time (2 and 24 h) and temperature (25 and 40 °C) to produce 12 material samples. The materials were characterized by energy dispersive x-ray, hexamethyldisilazane, digital radiography x-ray, Fourier-transform infrared, thermogravimetric analysis, and scanning electron microscopy. Additionally, the F-release kinetic profile was evaluated for 21 d in neutral and acid media with mathematical model analysis. Products with varying F-quantities were obtained, revealing specific release profiles. In general, there was a higher F-release in the acid medium, with emphasis on F-LDH-8. Fluoride-LDH and controlled fluoride delivery was successfully obtained, proving the potential of these nanomaterials as alternative anti-caries agents.

5.
Ciênc. rural (Online) ; 51(9): e20200936, 2021. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1249570

RESUMO

ABSTRACT: Methicillin resistance in the Staphylococcus intermedius group (SIG) has emerged in small animal practice. Methicillin-resistant SIG (MRSIG) members have been implicated as causes of infections in both companion animals and humans. Staphylococcal cassette chromosome mec (SCCmec) elements carry the mecA/C genes, which encode for the transpeptidase PBP2a (PBP2') responsible for β-lactam antibiotic resistance in staphylococci. This study examined the SCCmec types of MRSIG isolates from different clinical specimens of dogs that exhibited methicillin MIC ≥ 0.5 μg/mL by an automated identification and susceptibility system in a Center for Veterinary Diagnostics in São Paulo, Brazil. Susceptibility to methicillin was determined by broth microdilution testing, and Oxoid® M.I.C.Evaluator® strips. PBP2a production was detected using a latex agglutination assay. SCCmec typing was performed according to the International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements (IWG-SCC) guidelines. SCCmec type II (2A), SCCmec type III (3A), composite SCC structures consisting of a class A mec gene complex in addition to multiple ccr gene complexes, and non-typable SCCmec elements were reported in these MRSIG isolates. SCCmec type variants differing from those so far acknowledged by IWG-SCC were found, indicating new rearrangements in the genetic context of mecA in these canine MRSIG isolates.


RESUMO: A resistência à meticilina no grupo Staphylococcus intermedius (GSI) tem aumentado na clínica de pequenos animais. Membros GSI resistentes à meticilina (GSIRM) têm sido causas de infecções tanto em animais de companhia e humanos. Cassetes cromossômicos estafilocócicos mec (SCCmec) carregam os genes mecA/C, que codificam a transpeptidase PBP2a (PBP2') responsável pela resistência aos antibióticos β-lactâmicos em estafilococos. Nosso objetivo foi investigar os elementos SCCmec de GSIRM isolados de diferentes amostras clínicas de cães que exibiram CIM de meticilina ≥ 0,5 μg/mL por meio de um sistema automatizado em um Centro Veterinário de Diagnósticos em São Paulo, Brasil. A sensibilidade à meticilina foi determinada por meio do teste de microdiluição em caldo e fitas Oxoid® M.I.C.Evaluator®. A produção de PBP2a foi detectada usando um ensaio de aglutinação de látex. A tipagem dos elementos SCCmec foi realizada de acordo com as diretrizes do International Working Group on the Classification of Staphylococcal Cassette Chromosome Elements (IWG-SCC). SCCmec tipo II (2A), SCCmec tipo III (3A), SCC compostos de um complexo mec de classe A com múltiplos complexos ccr, e elementos SCCmec não tipáveis foram encontrados nesses isolados GSIRM. Variantes que diferem dos elementos SCCmec reconhecidos até o momento pelo IWG-SCC foram encontradas, indicando novos rearranjos no contexto genético de mecA nesses isolados GSIRM caninos.

6.
Einstein (Sao Paulo) ; 17(1): eRW4456, 2019 Feb 18.
Artigo em Inglês, Português | MEDLINE | ID: mdl-30785475

RESUMO

Layered double hydroxides have received more attention from researchers due to their range of applications, ease of synthesis and low cost of production. With broader knowledge about solar radiation effects on the body, the use of sunscreens has become even more important. The ability of some nanostructures, such as layered double hydroxides, to act as matrices has made it possible to obtain improvements in photoprotective formulations, with solutions to problems caused by radiation and sunscreens. This review article brings together the most recent advances of these clays, the layered double hydroxides, applied to photoprotection.


Assuntos
Hidróxidos/química , Nanoestruturas/química , Proteção Radiológica/métodos , Queimadura Solar/prevenção & controle , Protetores Solares/química , Raios Ultravioleta , Humanos
7.
Einstein (Säo Paulo) ; 17(1): eRW4456, 2019. tab
Artigo em Inglês | LILACS | ID: biblio-984367

RESUMO

ABSTRACT Layered double hydroxides have received more attention from researchers due to their range of applications, ease of synthesis and low cost of production. With broader knowledge about solar radiation effects on the body, the use of sunscreens has become even more important. The ability of some nanostructures, such as layered double hydroxides, to act as matrices has made it possible to obtain improvements in photoprotective formulations, with solutions to problems caused by radiation and sunscreens. This review article brings together the most recent advances of these clays, the layered double hydroxides, applied to photoprotection.


RESUMO Os hidróxidos duplos lamelares vêm ganhando maior atenção de pesquisadores, em decorrência da gama de aplicações, da facilidade de síntese e do baixo custo de produção. Com o crescente conhecimento sobre diversos efeitos da radiação solar sobre o organismo, a utilização de fotoprotetores tem se tornado indispensável. A capacidade de nanoestruturas, como os hidróxidos duplos lamelares, atuarem como matrizes possibilitou melhorias nas formulações fotoprotetoras, tendo em vista os problemas provocados pela radiação, bem como por alguns filtros solares. Este artigo de revisão reúne os avanços mais recentes destas argilas, os hidróxidos duplos lamelares, aplicados à fotoproteção.


Assuntos
Humanos , Proteção Radiológica/métodos , Queimadura Solar/prevenção & controle , Protetores Solares/química , Raios Ultravioleta , Nanoestruturas/química , Hidróxidos/química
8.
Insects ; 8(3)2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28902170

RESUMO

Lipases have key roles in insect lipid acquisition, storage, and mobilization and are also fundamental to many physiological processes in insects. Lipids are an important component of insect diets, where they are hydrolyzed in the midgut lumen, absorbed, and used for the synthesis of complex lipids. The South American palm weevil Rhynchophorus palmarum is one of the most important pests on commercial palm plantations. However, there are few studies about lipid digestion for this insect. In this work, we have described the biochemical characterization of the lipase activity in the posterior midgut of the R. palmarum palm weevil. Lipase activity was highest between the temperatures of 37 °C and 45 °C and at pH 6.5. Lipase activity was also sensitive to variations in salt and calcium concentrations. Lipases have been described structurally as enzymes with the Ser-His-Asp Catalytic Triad, containing an active serine. The serine protease inhibitor PMSF (phenylmethane sulfonyl fluoride) inhibited the lipases from R. palmarum, demonstrating the importance of a serine residue for this activity. The ability of the lipases to hydrolyze p-Nitrophenyl esters with different chain lengths has revealed the activities of a broad range of substrates. The lipase activities of R. palmarum increased in the presence of reduced glutathione (GSH) and dithiothreitol (DTT), while in the presence of oxidized glutathione (GSSG), activities were drastically reduced. To our knowledge, this study has provided the first information about lipase activity in the R. palmarum palm weevil.

9.
J Pharm Biomed Anal ; 73: 18-23, 2013 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-22361660

RESUMO

In recent years, thermal analysis has assumed major role in the pharmaceutical industry because it can be used to evaluate the stability both in the control of raw materials and the finished product, having employment potential in the development and characterization of new products and assessment processes. Tacrolimus (TCR) is a macrolide lactone with potent immunosuppressive activity. The purpose of this study was to characterize tacrolimus raw material using Thermal analysis and Pyrolysis coupled to Gas chromatography-Mass spectrometry (Pyr-GC-MS). It was analyzed four samples of tacrolimus named TCR A, B, C and D. Thermal analysis experiments was performed in Shimadzu equipment, under nitrogen and synthetic air atmosphere in different heating rate. Pyrolysis analysis was conducted in isothermal conditions of 300°C and 400°C coupled to GC-MS, in which the mass spectrometer was operated in scan mode to detect ions in the range of mass of m/z 25-900. The thermal studies by DSC, DTA and DSC-Photovisual showed desolvation process for all tacrolimus raw materials and TG-dynamical demonstrated two pseudo-polymorphic forms (monohydrate and sesquihydrate) of tacrolimus. It was observed good correlation between the stoichiometric mass losses of the TG-dynamical and identification of product ion in Pyr-GC/MS technique. It was possible to correlate the five pyrolytic product ions with the Ozawa kinetic analysis from the thermal decomposition of TG-dynamical. The thermal studies (DSC, DSC-Photovisual, DTA and TG-dynamical) were applied in the thermal characterization of the raw materials of tacrolimus which showed pseudo-polymorphic forms, which must be monitored by pharmaceutical industry, avoiding future problems in pharmaceutical process, chemical stability and bioavailability of the tacrolimus product.


Assuntos
Imunossupressores/química , Tacrolimo/química , Tecnologia Farmacêutica/métodos , Varredura Diferencial de Calorimetria/instrumentação , Varredura Diferencial de Calorimetria/métodos , Estabilidade de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas/instrumentação , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura Alta , Imunossupressores/normas , Cinética , Reprodutibilidade dos Testes , Tacrolimo/normas , Tecnologia Farmacêutica/instrumentação , Termogravimetria/instrumentação , Termogravimetria/métodos
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