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1.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469372

RESUMO

Abstract Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Resumo Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.

2.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360228

RESUMO

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Nanopartículas (NPs) são partículas insolúveis com diâmetro inferior a 100 nanômetros. Dois métodos principais têm sido utilizados na terapia ortodôntica para evitar a aderência microbiana ou a desmineralização do esmalte: NPs são incluídas em adesivos ortodônticos ou resinas acrílicas (fluoro-hidroxiapatita, fluorapatita, hidroxiapatita, SiO2, TiO2, prata, nanopreenchimentos) e NPs são revestidas nas superfícies de equipamentos ortodônticos, ou seja, uma camada fina de TiO2 dopado com nitrogênio nas superfícies do braquete. Embora o uso de NPs em ortodontia possa tornar acessível modernos recursos, pesquisas anteriores analisaram as características antibacterianas ou físicas por um período limitado de tempo, variando de 24 horas a várias semanas, por isso devem ser compreendidos os limites dos estudos in vitro. A eficácia de longo prazo de materiais ortodônticos com base em nanotecnologia ainda não foi confirmada de forma conclusiva, o que exige mais estudos, bem como potenciais preocupações de segurança (efeitos tóxicos) associadas ao tamanho da NP.


Assuntos
Ortodontia , Desmineralização , Esmalte Dentário , Nanopartículas , Anti-Infecciosos
3.
Braz J Biol ; 84: e265825, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36700585

RESUMO

The advancements in the cell culture studies have led to the development of regenerative medicine concept. The aim of this study is to compare the effectiveness of some washing solutions, including phosphate buffered saline (PBS), sodium chloride (NaCl), and ringer's lactate (RL) on the rate of detachment and confluency in fibroblast and osteoblast cell culture. Baby Hamster Kidney 21 clone 13 (BHK21/C13) fibroblast cells and 7F2 osteoblast were cultured on T25 flasks for 3-4 days. Three treatment groups were classified on the basis of different washing solutions used in the moment before trypsinization: PBS, 0.9% NaCl, and RL. Each group was measured for the detachment rate and cell confluence. The measurement was done in 2 passage numbers. The use of PBS, NaCl, and RL washing solution showed that detachment time was less than 5 minutes for the fibroblasts and 3 minutes for the osteoblasts. There was a significant difference in the rate of fibroblast cell detachment (p=0.006) and osteoblast (p=0.016). The capability of fibroblasts and osteoblasts to achieve a confluence of 106 cells/well on the first and second measurements was almost the same between the washing solution groups. The use of physiological 0.9% NaCl solution as a washing solution in fibroblast and osteoblast cell culture has almost the same effectiveness as PBS to help accelerate cell detachment in less than 5 minutes without influencing the capability of cells to proliferate.


Assuntos
Técnicas de Cultura de Células , Solução Salina , Cloreto de Sódio , Humanos , Fibroblastos , Soluções Isotônicas/farmacologia , Osteoblastos , Lactato de Ringer , Cloreto de Sódio/farmacologia
4.
Eur Rev Med Pharmacol Sci ; 26(19): 7099-7114, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36263558

RESUMO

OBJECTIVE: Despite apoptosis processes being conserved, cancer cells have developed mechanisms to inhibit apoptosis by altering anti-apoptotic molecules or inactivating pro-apoptotic. The aim of this study was to determine the palmitic acid of Musa paradisiaca var. sapientum (L) Kunz (MP) stem extracts against human oral squamous cell carcinoma (hOSCC) through caspase-3. MATERIALS AND METHODS: Ethanol and ethyl acetate extracts of MP stem were analyzed by gas chromatography-mass spectrometry (GC-MS). Computerized models of chemically active compounds were used to predict anticancer activity. Cytotoxicity was evaluated in Artemia salina Leach and hOSCC (OM-1) culture at concentrations 100, 90, 80, 70, 60, 50, 40, 30, 20, and 10 µg/mL respectively. The expression level of caspase-3 on hOSCC was measured by enzyme-linked immunoassay (ELISA). RESULTS: We found seven chemically active compounds in the ethanol extract and 15 compounds in the ethyl acetate extract of MP stem. The major component was hexadecanoic acid of palmitic acid derivates, and this was predicted to have anticancer activities as apoptosis through caspase-3 stimulants. However, cytotoxicity effects against hOSCC culture were assessed by values of the 50% inhibitory concentration (IC50) of 15.00 µg/mL for the ethanol extract, and an IC50 of 10.61 µg/mL for the ethyl acetate. There was a significant increase of caspase-3 level on treatment groups compared to control. CONCLUSIONS: Hexadecanoic acid of MP stem extracts has anticancer activity by inhibiting cell growth of hOSCC culture through caspase-3 stimulants.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Musa , Humanos , Musa/química , Musa/metabolismo , Caspase 3/metabolismo , Ácido Palmítico/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Carcinoma de Células Escamosas de Cabeça e Pescoço , Neoplasias Bucais/tratamento farmacológico , Apoptose , Etanol
5.
Braz J Biol ; 84: e257070, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35195179

RESUMO

Nanoparticles (NPs) are insoluble particles with a diameter of fewer than 100 nanometers. Two main methods have been utilized in orthodontic therapy to avoid microbial adherence or enamel demineralization. Certain NPs are included in orthodontic adhesives or acrylic resins (fluorohydroxyapatite, fluorapatite, hydroxyapatite, SiO2, TiO2, silver, nanofillers), and NPs (i.e., a thin layer of nitrogen-doped TiO2 on the bracket surfaces) are coated on the surfaces of orthodontic equipment. Although using NPs in orthodontics may open up modern facilities, prior research looked at antibacterial or physical characteristics for a limited period of time, ranging from one day to several weeks, and the limits of in vitro studies must be understood. The long-term effectiveness of nanotechnology-based orthodontic materials has not yet been conclusively confirmed and needs further study, as well as potential safety concerns (toxic effects) associated with NP size.


Assuntos
Braquetes Ortodônticos , Ortodontia , Antibacterianos , Braquetes Ortodônticos/microbiologia , Dióxido de Silício , Titânio
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