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1.
Braz. j. biol ; 84: e257070, 2024. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1360228

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.


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.


Subject(s)
Orthodontics , Demineralization , Dental Enamel , Nanoparticles , Anti-Infective Agents
2.
Braz. j. biol ; 84: e253555, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1355900

ABSTRACT

Abstract The aim of the present study is to assess the effects of selenium nanoparticles on the growth, hematology and nutrients digestibility of Labeorohita fingerlings. Fingerlings were fed with seven isocaloric sunflower meal-based diet supplemented with different concentrations of nanoparticles naming T1 to T7 (0, 0.5, 1, 1.5, 2, 2.5, and 3 mg/kg), with 5% wet body weight while chromic oxide was used as an indigestible marker. After experimentation for 90 days T3 treated group (1mg/kg -1Se-nano level) showed the best result in hematological parameters (WBC's 7.97 ×103mm-3, RBC's 2.98 ×106 mm-3 and Platelet count 67), nutrient digestibility (crude protein: 74%, ether extract: 76%, gross energy: 70%) and growth performance (weight gain 13.24 g, weight gain% 198, feed conversion ratio 1.5, survival rate 100%) as compared to the other treatment groups. Specific growth rates were found significantly higher in T5 than in other groups. The present study indicated positive effect of 1 mg/kg Se-nanoparticles on growth advancement, hematological parameters, and nutrients digestibility of L. rohita fingerlings.


Resumo O objetivo do presente estudo é avaliar os efeitos das nanopartículas de selênio no crescimento, hematologia e digestibilidade dos nutrientes de alevinos de Labeo rohita. Os alevinos foram alimentados com sete dietas isocalóricas à base de farinha de girassol suplementada com diferentes concentrações de nanopartículas, nomeando T1 a T7 (0, 0,5, 1, 1,5, 2, 2,5 e 3 mg / kg), com 5% do peso corporal úmido enquanto o óxido crômico foi usado como um marcador indigesto. Após a experimentação por 90 dias, o grupo tratado com T3 (nível 1mg / kg -1Se-nano) mostrou o melhor resultado em parâmetros hematológicos (WBC's 7,97 × 103mm-3, RBC's 2,98 × 106mm-3 e contagem de plaquetas 67), digestibilidade dos nutrientes (proteína bruta: 74%, extrato de éter: 76%, energia bruta: 70%) e desempenho de crescimento (ganho de peso 13,24 g, ganho de peso % 198, taxa de conversão alimentar 1,5, taxa de sobrevivência 100%) em comparação com os outros grupos de tratamento. As taxas de crescimento específicas foram encontradas significativamente mais altas em T5 do que em outros grupos. O presente estudo indicou efeito positivo de 1 mg / kg de nanopartículas de Se no avanço do crescimento, parâmetros hematológicos e digestibilidade de nutrientes de alevinos de L. rohita.


Subject(s)
Animals , Nanoparticles , Helianthus , Nutrients , Dietary Supplements , Diet , Animal Feed/analysis , Animal Nutritional Physiological Phenomena
3.
Rev. ADM ; 79(4)jul.-ago. 2022. ilus, tab
Article in Spanish | LILACS | ID: biblio-1395261

ABSTRACT

Introducción: el biofilm dental microbiano es el precursor de diversas enfermedades orales, una de ellas la caries, ésta representa la enferme- dad oral más significativa a nivel mundial, con una incidencia de 1.76 billones de niños afectados. Las nanopartículas de plata (AgNPs) se están usando como alternativa para el control y prevención del biofilm dental, ya que poseen propiedades antimicrobianas contra bacterias relacionadas a estas enfermedades. Sin embargo, no hay estudios que evalúen este comportamiento en pacientes pediátricos. Objetivo: eva- luar la actividad antimicrobiana de las AgNPs en bacterias de aislados clínicos tomados de pacientes pediátricos. Material y métodos: se tomó muestra del biofilm dental de 22 pacientes pediátricos, el efecto micro- biológico se evaluó mediante ensayos microbiológicos estandarizados internacionalmente por triplicado, usando dos diferentes tamaños de AgNPs. Resultados: los dos tamaños de AgNPs mostraron inhibición bacteriana, sin embargo, sólo se vio una diferencia estadísticamente significativa entre el género (p < 0.05), además, en general, hubo una correlación positiva significativa en relación a la concentración de las AgNPs y la velocidad del crecimiento bacteriano (p < 0.05). Conclusión: las AgNPs se pueden considerar como una alternativa para la prevención del biofilm dental y de esta manera para el control de diferentes enfermedades orales (AU))


Introduction: dental biofilm is the precursor of oral diseases, one of them dental caries, this represents the most significant oral disease worldwide with an incidence of 1.76 billion affected children. Silver nanoparticles (AgNPs) are being used as an alternative for the control and prevention of dental biofilm since they have antimicrobial properties against bacteria related to these diseases. However, there are no studies evaluating this behavior in pediatric patients. Objective: to evaluate the antimicrobial activity of AgNPs in bacteria from clinical isolates taken from pediatric patients. Material and methods: a sample of dental biofilm was taken from 22 pediatric patients, the microbiological effect was evaluated by international standardized microbiological tests in triplicate, using two different sizes of AgNPs. Results: the two sizes of AgNPs showed bacterial inhibition, however, only a statistically significant difference was seen between gender (p < 0.05), in addition, in general, there was a significant positive correlation in relation to the concentration of AgNPs and the speed bacterial growth (p < 0.05). Conclusion: AgNPs can be considered as an alternative for the prevention of dental biofilm and thus for the control of different oral diseases (AU)


Subject(s)
Humans , Male , Female , Child, Preschool , Child , Dental Caries/prevention & control , Dental Plaque/prevention & control , Nanoparticles/therapeutic use , Bacterial Growth , Dental Care for Children/methods , Culture Media , Dental Plaque/microbiology , Age and Sex Distribution
4.
Int. j. high dilution res ; 21: 67-84, June 20, 2022.
Article in English | LILACS, HomeoIndex | ID: biblio-1396376

ABSTRACT

Homeopathy is highly controversial. The main reason for this is its use of very highly dilute medicines (high homeopathic potencies, HHP), diluted beyond the Avogadro/Loschmidt limit. Research using Nano Tracking Analysis has demonstrated the presence of particles in HHPs. This study aims to verify the results of a previous publication that identified the ionic composition of these particles in all dilutions. We used Scanning Electron Microscopy & Energy Dispersive X-Ray Spectroscopy (SEM-EDX) to examine dilutions of a commonly used homeopathic medicine, an insoluble metal, Cuprum metallicum, for the presence of particles (NPs). The homeopathic medicines tested were specially prepared according to the European pharmacopoeia standards. We compared the homeopathic dilutions/dynamizations of copper with simple dilutions and dynamized lactose controls. We observed an ionic diversity common to all preparations including HHPs but also significant differences in the relative quantity of each ion between manufacturing lines of homeopathic copper and lactose controls. The probability that the observed differences could have occurred chance alone (especially above Avogadro limit) can be rejected at p < 0.001. The essential component of these homeopathic medicines is sodium hydrogen carbonate, modulated by some other elements and by its quantity, size and shape. Homeopathic medicines made of Cuprum metallicum do contain material with a specific ionic composition even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing process. This material demonstrates that the step-by-step process (dynamized or not) does not match the theoretical expectations of a dilution process. The starting material and dilution/dynamization method influences the nature of these NPs. Further measurements are needed on other raw materials using the same controls (solvent and simply diluted manufacturing lines) to support these findings. The role of sodium bicarbonate must be carefully studied in the future.


Subject(s)
Dynamization , Homeopathic Pharmacotechniques , Nanoparticles , Spectrometry, X-Ray Emission , Microscopy, Electron, Scanning , Cuprum Metallicum , Sodium Bicarbonate , Copper , Lactose
5.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 323-342, mayo 2022. tab, ilus
Article in English | LILACS | ID: biblio-1396881

ABSTRACT

Copaifera spp. essential oil (EOC) was extracted by hydrodistillation of Copaifera oleoresin (COR). The EOC was characterized by GC/MS and a novel EOC-loaded nanoemulsion was developed to enhance the EOC solubility and to evaluate its utility as antinflammatory. EOC contain 14 volatile compounds (including ß-caryophyllene: 51.52%) having a required HLB of 11. The Surfactant: EOC: Water ratio of 13:15:75 (%, w:w:w) produced the optimal formulation (particle size: 94.47 nm). The EOC-loaded nanoemulsion presented a pseudoplastic/thixotropic behavior with excellent shelf stability for 6 months. The anti-inflammatory effect of the nanoemulsion was more potent than that of the EOC, and statistically equal to diclofenac (50 mg/kg). The EOC-loaded nanoemulsion showed no oral acute toxicity (in mice) at 2000 mg/kg; hence, it is considered a nontoxic product. The development of the EOC-loaded nanoemulsion added value to both the COR and the EOC by providinga suitable formulation that could be used as an anti-inflammatory product.


El aceite esencial (EOC) fue extraído por hidrodestilación de oleoresina de Copaifera spp. El EOC fue caracterizado químicamente por GC/MS. Se formuló una nanoemulsión con EOC para mejorar la solubilidad del EOC y evaluar su utilidad como antiinflamatorio. El EOC contiene 14 compuestos volátiles (incluido el ß-cariofileno: 51,52%) con un HLB requerido de 11. La relación Tensioactivo: EOC: Agua de 13:15:75 (%, p:p:p) produjo la formulación óptima (tamaño de partícula: 94,47 nm).. La nanoemulsión cargada con EOC presentó un comportamiento pseudoplástico/tixotrópico con una excelente estabilidad en almacenamiento durante 6 meses. El efecto antiinflamatorio de la nanoemulsión fue más potente que el del EOC y estadísticamente igual al diclofenaco (50 mg/kg). La nanoemulsión cargada con COE no mostró toxicidad aguda oral (en ratones) a 2000 mg/kg; por lo tanto, se considera un producto no tóxico. El desarrollo de la nanoemulsión cargada con EOC agregó valor tanto al COR como al EOC al proporcionar una formulación adecuada que podría usarse como un producto antiinflamatorio.


Subject(s)
Animals , Mice , Oils, Volatile/pharmacology , Fabaceae/chemistry , Anti-Inflammatory Agents/pharmacology , Rheology , Surface-Active Agents , Temperature , Oils, Volatile/chemistry , Toxicity Tests, Acute , Emulsions/pharmacology , Nanoparticles , Polycyclic Sesquiterpenes/analysis , Hydrogen-Ion Concentration , Gas Chromatography-Mass Spectrometry
6.
Int. j. high dilution res ; 21(2): 2-3, May 6, 2022.
Article in English | LILACS, HomeoIndex | ID: biblio-1396754

ABSTRACT

Homeopathy is controversial because using highly dilute medicines (high homeopathic potencies, HHP) beyond the Avogadro/Loschmidt limit. Previous publications [1,2] using NMR relaxation revealed the involvement of nanobubbles and/or nanoparticles and/or nanometric superstructures in high potentizations. Nano Tracking Analyse (NTA) demonstrated the presence of particles in HHPs [3,4]. WithSEM-EDX [5] we observed an ionic diversity common to all preparations including HHPs and significant differences in the relative quantity of each ion between different homeopathic manufacturing lines and controls. FTIR spectroscopy [6] shows that the molecular composition is that of carbonates, primarily sodium bicarbonate.Methods:To observe the materiality of homeopathic medicines a multidisciplinary approach is necessary. In collaboration with several universities,we canobserve these medications with NMR, NTA, SEM-EDX, FTIR, pH,and EPA. Results:The essential component of all already studied homeopathic medicines is sodium hydrogen carbonate modulated by some other elements in a specific quantity, size,and shape. The probability that the observed results could have occurred just by random chance can be rejected(significantlyabove the Avogadro limit) p < 0,001.Conclusions:The homeopathic medicines do contain material with a specific ionic composition even in HHPs diluted beyond the Avogadro/Loschmidt limit. This specificity can be attributed to the manufacturing process. These results demonstrate that the step-by-step process (dynamized or not) does not match the theoretical expectations in a dilution process. The starting material and dilution/dynamization method influencethe nature of these NPs. The role of carbonates and sodium bicarbonate must be carefully studied in the future. Its aqueous solution is alkaline in nature but itis an amphoteric compound, which means that the compound has both acidic as well as alkaline character. The reaction with acids results in sodium salts and carbonic acid and the reaction with the basic solution producescarbonates and water. Specific electric fields are indeed detectable.


Subject(s)
Materia Medica , Dynamization , Nanoparticles , Microscopy, Electron, Scanning , Sodium Bicarbonate/analysis
7.
J. oral res. (Impresa) ; 11(1): 1-13, may. 11, 2022. ilus
Article in English | LILACS | ID: biblio-1398893

ABSTRACT

Introduction: This study aimed to prepare a new root repair material including Portland cement, bismuth oxide, and nano-hydroxyapatite and analyze its physicochemical properties and its effects on the proliferation and differentiation of human dental pulp stem cells (hDPSCs). Material and Methods: Bismuth oxide as a radiopaque component and nano-hydroxyapatite particles were added to white Portland cement at 20% and 5% weight ratio, respectively. Characterization of the prepared cement was done using conventional methods. To examine the bioactivity of this new material, atomic absorption spectroscopy (AAS) was used for the investigation of the rate of calcium ions dissolution in simulated body fluid media. The viability of hDPSCs was assessed by an MTT assay after 1, 3 and 7 days. The odontogenic potential of this substance was evaluated by measuring alkaline phosphatase activity and alizarin red S staining. Results: Based on the bioactivity results, the cement presented high bio-activity, corroborating sufficiently with the calcium release patterns. The cell viability was significantly increased in new root repair material containing hydroxyapatite nanoparticles after 3 and 7 days (p<0.05). Conclusion: Moreover, alkaline phosphatase activity increased over 7 days in all experimental groups. The new cement containing nano-hydroxyapatite particles could be a good root repair material.


Objetivo: Este estudio tuvo como objetivo preparar un nuevo material de reparación de raíces que incluye cemento Portland, óxido de bismuto y nano-hidroxiapatita y analizar sus propiedades fisicoquímicas y sus efectos sobre la proliferación y diferenciación de células madre de pulpa dental humana. Material y Métodos: El óxido de bismuto como compo-nente radiopaco y las partículas de nano-hidroxiapatita se agregaron al cemento Portland blanco en una proporción en peso del 20 % y el 5 %, respectivamente. La caracterización del cemento preparado se realizó utilizando métodos con-vencionales. Para examinar la bioactividad de este nuevo material, se utilizó la espectroscopia de absorción atómica para investigar la velocidad de disolución de los iones de calcio en medio fluido corporal simulado. La viabilidad de las células madre de pulpa dental humana se evaluó mediante un ensayo MTT después de 1, 3 y 7 días. El potencial odontogénico de esta sustancia se evaluó midiendo la actividad de la fosfatasa alcalina y la tinción con rojo de alizarina S.Resultados: Con base en los resultados de bioactividad, el cemento presentó alta bioactividad, corroborando suficientemente con los patrones de liberación de calcio. La viabilidad celular aumentó significativamente en el nuevo material de reparación de raíces que contenía nanopartículas de hidroxiapatita después de 3 y 7 días (p<0,05). Conclusión: Además, la actividad de la fosfatasa alcalina aumentó durante 7 días en todos los grupos experimentales. El nuevo cemento que contiene partículas de nanohidroxiapatita podría ser un buen material de reparación radicular.


Subject(s)
Humans , Bismuthum Oxydatum , Silicates/chemical synthesis , Durapatite/chemical synthesis , Dental Cementum/chemistry , Root Canal Filling Materials , Stem Cells , Dental Pulp , Nanoparticles
8.
Braz. j. biol ; 82: e237214, 2022. tab, graf
Article in English | LILACS | ID: biblio-1249258

ABSTRACT

Abstract Artemisia absinthium L. is an important herb that is widely cultivated in different parts of the world for its medicinal properties. The present study evaluated the effects of four concentrations of nanoparticles treatment (0, 10, 20 and 30 mg L-1) and NaCl salinity stress (0, 50, 100 and 150 mM NaCl) and their interactions with respect to the expression of two key genes, i.e. DBR2 and ADS, in the biosynthesis pathway of artemisinin in A. absinthium. Total RNA was extracted and a relative gene expression analysis was carried out using Real-Time PCR. The amount of artemisinin was also determined by HPLC. All the experiments were performed as factorial in a completely randomized design in three replications. The results revealed that salinity stress and nanoparticles treatment and their interaction affected the expressions of these genes significantly. The highest levels of ADS gene expression were observed in the 30 mg L-1 nanoparticles-treated plants in the presence of 150 mM salinity stress and the lowest levels in the 10 mg L-1 nanoparticles-treated plants under 50 mM salinity stress. The maximum DBR2 gene expression was recorded in the 10 mg L-1 nanoparticles-treated plants in the absence of salinity stress and the minimum expression in the 100 mM salinity-stressed plants in the absence of nanoparticles treatment. Moreover, the smallest amounts of artemisinin were observed in the 150 mM salinity-stressed plants in the absence of nanoparticles and the highest amounts in the 30 mg L-1 nanoparticles-treated plants. The maximum amounts of artemisinin and ADS gene expression were reported from the plants in the same nanoparticles treatment and salinity stress conditions. In this regard, the amount of artemisinin was decreased by half in the plants containing the highest DBR2 gene expression. Meanwhile, no significant correlation was observed between these gene expressions and the artemisinin amount in the other nanoparticles-treated plants under different levels of salinity stress. The biosynthetic pathway of secondary metabolites appears to be very complex and dose not directly dependent on these gene expressions.


Resumo Artemisia absinthium L. é uma erva importante que é amplamente cultivada em diferentes partes do mundo por suas propriedades medicinais. O presente estudo avaliou os efeitos de quatro concentrações de tratamento com nanopartículas (0, 10, 20 e 30 mg L-1) e estresse de salinidade com NaCl (0, 50, 100 e 150 mM NaCl) e suas interações com relação à expressão de dois genes-chave, isto é, DBR2 e ADS, na via de biossíntese da artemisinina em A. absinthium. O RNA total foi extraído, e uma análise de expressão gênica relativa foi realizada usando PCR em tempo real. A quantidade de artemisinina também foi determinada por HPLC. Todos os experimentos foram realizados como fatorial, em delineamento inteiramente casualizado, em três repetições. Os resultados revelaram que o estresse por salinidade e o tratamento com nanopartículas e sua interação afetaram significativamente as expressões desses genes. Os níveis mais altos de expressão do gene ADS foram observados nas plantas tratadas com nanopartículas de 30 mg L-1 na presença de estresse de salinidade de 150 mM, e os níveis mais baixos, nas plantas tratadas com nanopartículas de 10 mg L-1 com estresse de salinidade de 50 mM. A expressão máxima do gene DBR2 foi registrada nas plantas tratadas com nanopartículas de 10 mg L-1 na ausência de estresse de salinidade, e a expressão mínima, nas plantas estressadas com salinidade de 100 mM na ausência de tratamento com nanopartículas. Além disso, as menores quantidades de artemisinina foram observadas nas plantas com estresse de salinidade de 150 mM na ausência de nanopartículas, e as maiores quantidades, nas plantas tratadas com nanopartículas de 30 mg L-1. As quantidades máximas de expressão de genes de artemisinina e ADS foram relatadas a partir das plantas no mesmo tratamento com nanopartículas e condições de estresse de salinidade. A esse respeito, a quantidade de artemisinina diminuiu pela metade nas plantas que contêm a expressão gênica DBR2 mais alta. Enquanto isso, nenhuma correlação significativa foi observada entre essas expressões gênicas e a quantidade de artemisinina nas outras plantas tratadas com nanopartículas sob diferentes níveis de estresse de salinidade. A via biossintética dos metabólitos secundários parece ser muito complexa e não depende diretamente dessas expressões gênicas.


Subject(s)
Artemisia absinthium/genetics , Artemisia annua , Artemisinins , Nanoparticles , Plant Proteins , Titanium , Salt Stress
9.
Braz. J. Pharm. Sci. (Online) ; 58: e19586, 2022. tab, graf
Article in English | LILACS | ID: biblio-1384008

ABSTRACT

Abstract Design of experiment (DoE) is a useful time and cost-effective tool for analyzing the effect of independent variables on the formulation characteristics. The aim of this study is to evaluate the effect of the process variables on the characteristics involved in the preparation of Diclofenac Sodium (DC) loaded ethylcellulose (EC) nanoparticles (NP) using Central Composite Design (CCD). NP were prepared by W/O/W emulsion solvent evaporation method. Three factors were investigated (DC/EC mass ratio, PVA concentration, homogenization speed) in order to optimize the entrapment efficiency (EE) and the particle size of NP. The optimal formulation was characterized by Fourier Transform Infrared (FTIR), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), and in vitro release. Optimized formulation showed an EE of 49.09 % and an average particle size of 226.83 nm with a polydispersity index of 0.271. No drug-polymer interaction was observed in FTIR and DSC analysis. SEM images showed that the particles are spherical and uniform. The in vitro release study showed a sustained release nature, 53.98 % of the encapsulated drug has been released over 24hours period. This study demonstrated that statistical experimental design methodology can optimize the formulation and the process variables to achieve favorable responses.


Subject(s)
Pharmaceutical Preparations , Diclofenac/analysis , Process Optimization , Nanoparticles/analysis , In Vitro Techniques/instrumentation , Calorimetry, Differential Scanning/instrumentation , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared , Costs and Cost Analysis/methods , Methodology as a Subject , Fourier Analysis
10.
Braz. dent. sci ; 25(3): 1-9, 2022. tab, ilus
Article in English | LILACS, BBO | ID: biblio-1373077

ABSTRACT

Objective: Thermally activated acrylic resins (RAATs) are widely used in dentures as a base material due to their good dimensional stability and biocompatibility. However, their low thermal conductivity is a disadvantage, as it affects acceptance when using dental prostheses. Thus, the objective of this work was to measure the conduction heat in RAATs with and without incorporation of silica and silver nanoparticles (NP) and rigid reline (RR). Material and Methods: For this, samples were made and divided into 10 groups (n = 6). The first five groups were 2-mm-thick samples: G1 (RAAT control), G2 (RAAT + RR control), G3 (RAAT and NP + RR), G4 (RAAT + RR and NP), and G5 (RAAT and RR modified by NP). In the other five groups, 8-mm-thick samples were made: G6 (RAAT control), G7 (RAAT + RR control), G8 (RAAT and NP + RR), G9 (RAAT + RR and NP), and G10 (RAAT and RR modified by NP). The heat that cross the surface of the specimens was quantified using a wireless device. The data were submitted to two-factor ANOVA statistical analysis and Tukey ́s test with a 5% significance level. Results: After measuring the temperature variation as a function of time, it can be observed that there was a statistically significant difference for thermal conduction between the control groups and those modified with NP. Conclusion: Thus, it was possible to conclude that the NP improved the heat conduction in RAAT and in the RR because the nanoparticles have a higher thermal conductivity. (AU)


Objetivo: As resinas acrílicas termicamente ativadas (RAATs) são amplamente utilizada em próteses dentárias como material de base, pois possuem uma boa estabilidade dimensional e biocompatibilidade. Porém, como desvantagem, possuem baixa condutividade térmica, o que prejudica a aceitação do uso de próteses dentárias. Assim, o objetivo deste trabalho foi medir a condução de calor em RAAT com e sem incorporação de nanopartículas de sílica e prata (NP) e reembasador rígido (RR). Material e Métodos: Para isso, foram confeccionadas amostras que foram divididas em 10 grupos (n=6). Os primeiros cinco grupos eram amostras de 2 mm de espessura: G1 (RAAT controle), G2 (RAAT + RR controle), G3 (RAAT e NP + RR), G4 (RAAT + RR e NP) e G5 (RAAT e RR modificados por NP). E nos outros cinco grupos foram feitas amostras com espessura de 8 mm: G6 (RAAT controle), G7 (RAAT + RR controle), G8 (RAAT e NP + RR), G9 (RAAT + RR e NP) e G10 (RAAT e RR modificados por NP). O calor percorrido pela superfície dos corpos ­ de prova foi quantificado por meio de um dispositivo sem fio. Os dados foram submetidos à análise estatística ANOVA dois fatores e teste de Tukey com 5% de significância. Resultados: Após medir a variação da temperatura em função do tempo, pode-se observar que houve diferença estatisticamente significante para a condução térmica entre os grupos controle e os modificados com NP. Conclusão: Assim, foi possível concluir que a NP melhorou a condução de calor na RAAT e no RR, pois as nanopartículas apresentam maior condutividade térmica. (AU)


Subject(s)
Thermal Conductivity , Acrylic Resins , Nanoparticles , Metal Nanoparticles
11.
Braz. J. Pharm. Sci. (Online) ; 58: e18800, 2022. tab, graf, ilus
Article in English | LILACS | ID: biblio-1364431

ABSTRACT

Abstract Efavirenz is one of the most commonly used drugs in HIV therapy. However the low water solubility tends to result in low bioavailability. Drug nanocrystals, should enhance the dissolution and consequently bioavailability. The aim of the present study was to obtain EFV nanocrystals prepared by an antisolvent technique and to further observe possible effect, on the resulting material, due to altering crystallization parameters. A solution containing EFV and a suitable solvent was added to an aqueous solution of particle stabilizers, under high shear agitation. Experimental conditions such as solvent/antisolvent ratio; drug load; solvent supersaturation; change of stabilizer; addition of milling step and solvents of different polarities were evaluated. Suspensions were characterized by particle size and zeta potential. After freeze- dried and the resulting powder was characterized by PXRD, infrared spectroscopy and SEM. Also dissolution profiles were obtained. Many alterations were not effective for enhancing EFV dissolution; some changes did not even produced nanosuspensions while other generated a different solid phase from the polymorph of raw material. Nevertheless reducing EFV load produced enhancement on dissolution profile. The most important modification was adding a milling step after precipitation. The resulting suspension was more uniform and the powder presented grater enhancement of dissolution efficacy.


Subject(s)
Efficacy/classification , HIV/pathogenicity , Crystallization/instrumentation , Dissolution/methods , Particle Size , Solubility , Pharmaceutical Preparations/administration & dosage , Excipients/pharmacology , Dissolution/classification , Nanoparticles/administration & dosage , Methods
12.
Braz. J. Pharm. Sci. (Online) ; 58: e18594, 2022. graf
Article in English | LILACS | ID: biblio-1364422

ABSTRACT

Abstract Traditionally dates is consumed as a rich source of iron supplement and the current research discuss the synthesis of silver nanoparticles (AgNPs) using methanolic seed extract of Rothan date and its application over in vitro anti-arthritic, anti-inflammatory and antiproliferative activity against lung cancer cell line (A549). FTIR result of synthesised AgNPs reveals the presence of functional group OH as capping agent. XRD pattern confirms the crystalline nature of the AgNPs with peaks at 38º, 44º, 64º and 81º, indexed by (111), (200), (220) and (222) in the 2θ range of 10-90, indicating the face centered cubic (fcc) structure of metallic Ag. HR- TEM results confirm the morphology of AgNPs as almost spherical with high surface areas and average size of 42 ± 9nm. EDX spectra confirmed that Ag is only the major element present and the Dynamic light scattering (DLS) assisted that the Z-average size was 203nm and 1.0 of PdI value. Zeta potential showed − 26.5mv with a single peak. The results of the biological activities of AgNPs exhibited dose dependent activity with 68.44% for arthritic, antiinflammatory with 63.32% inhibition and anti-proliferative activity illustrated IC50 value of 59.66 µg/mL expressing the potential of AgNPs to combat cancer


Subject(s)
Silver , In Vitro Techniques/methods , Chronology as Topic , Nanoparticles , Phoeniceae/adverse effects , Lung Neoplasms/classification , Seeds , zeta Potential , Spectroscopy, Fourier Transform Infrared , Inhibitory Concentration 50 , Dosage/methods
13.
Braz. J. Pharm. Sci. (Online) ; 58: e18719, 2022. tab, graf
Article in English | LILACS | ID: biblio-1364412

ABSTRACT

Abstract The aim of present study was calculate the Minimum inhibitory concentrations (MICs) of silver nanoparticles and clotrimazole for Candida species and their interaction by the adaptation of standarized methods. The MICs values of clotrimazole were 9 E-04-3 E-03 ug/ml, 0.1-0.6 ug/ml, 3 E-03- 0.1 ug/ml and 3 E-03-0.3 ug/ml for Candida albicans susceptible to fluconazole, Candida albicans resistance to fluconazole, Candida krusei and Candida parapsilosis respectively. The MICs values of silver nanoparticles were 26.50- 53 ug/ml; 26.50-106 ug/ml; 106-212 ug/ ml and 26.50- 53 ug/ml for Candida albicans susceptible to fluconazole, Candida albicans resistance to fluconazole, Candida krusei and Candida parapsilosis respectively. Synergism between clotrimazole and silver nanoparticles was measured by checkerboard BMD (broth microdilution) test and shown only for C. albicans susceptible to fluconazole because the fractional inhibitory concentrations (FICs) values were 0.07 - 0.15 ug/ml. Indifference was shown for the other species tested because the FICs values were between 0.5 - 2- 3.06 ug/ml. The results suggest synergistic activity depending on the fungus species analysed, however we recommend the incorporation of others measurement methodologies to confirm our results. As for measurement methodologies of MICs of silver nanoparticles and clotrimazole international normative were respected to guarantee reproducible and comparable results.


Subject(s)
Candida/classification , Clotrimazole/analogs & derivatives , Nanoparticles/administration & dosage , Antifungal Agents/adverse effects , Microbial Sensitivity Tests/instrumentation , Fungi
14.
Braz. J. Pharm. Sci. (Online) ; 58: e19519, 2022. tab, graf
Article in English | LILACS | ID: biblio-1383984

ABSTRACT

Abstract Silver nanoparticles (AgNPs) are among the most known nanomaterials being used for several purposes, including medical applications. In this study, Calendula officinalis L. flower extract and silver nitrate were used for green synthesis of silver nanoparticles under red, green and blue light-emitting diodes. AgNPs were characterized by Ultraviolet-Visible Spectrophotometry, Field Emission Scanning Electron Microscopy, Dynamic Light Scattering, Electrophoretic Mobility, Fourier Transform Infrared Spectroscopy and X-ray Diffraction. Isotropic and anisotropic silver nanoparticles were obtained, presenting hydrodinamic diameters ranging 90 - 180 nm, polydispersity (PdI > 0.2) and moderate stability (zeta potential values around - 20 mV)


Subject(s)
Silver , Silver Nitrate/agonists , Calendula/adverse effects , Flowers/genetics , Nanoparticles/analysis , Spectrophotometry/methods , X-Ray Diffraction/methods , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared , Light
15.
Article in Chinese | WPRIM | ID: wpr-936281

ABSTRACT

OBJECTIVE@#To construct a polylactic acid-glycolic acid-polyethylene glycol (PLGA-PEG) nanocarrier (N-Pac-CD133) coupled with a CD133 nucleic acid aptamer carrying paclitaxel for eliminating lung cancer stem cells (CSCs).@*METHODS@#Paclitaxel-loaded N-Pac-CD133 was prepared using the emulsion/solvent evaporation method and characterized. CD133+ lung CSCs were separated by magnetic bead separation and identified for their biological behaviors and gene expression profile. The efficiency of paclitaxel-loaded N-Pac-CD133 for targeted killing of lung cancer cells was assessed in vitro. SCID mice were inoculated with A549 cells and received injections of normal saline, empty nanocarrier linked with CD133 aptamer (N-CD133), paclitaxel, paclitaxel-loaded nanocarrier (N-Pac) or paclitaxel-loaded N-Pac-CD133 (n=8, 5 mg/kg paclitaxel) on days 10, 15 and 20, and the tumor weight and body weight of the mice were measured on day 40.@*RESULTS@#Paclitaxel-loaded N-Pac-CD133 showed a particle size of about 100 nm with a high encapsulation efficiency (>80%) and drug loading rate (>8%), and was capable of sustained drug release within 48 h. The CD133+ cell population in lung cancer cells showed the characteristic features of lung CSCs, including faster growth rate (30 days, P=0.001) and high expressions of tumor stem cell markers OV6(P < 0.001), CD133 (P=0.001), OCT3/4 (P=0.002), EpCAM (P=0.04), NANOG (P=0.005) and CD44 (P=0.02). Compared with N-Pac and free paclitaxel, paclitaxel-loaded N-Pac-CD133 showed significantly enhanced targeting ability and cytotoxicity against lung CSCs in vitro (P < 0.001) and significantly reduced the formation of tumor spheres (P < 0.001). In the tumor-bearing mice, paclitaxel-loaded N-Pac-CD133 showed the strongest effects in reducing the tumor mass among all the treatments (P < 0.001).@*CONCLUSION@#CD133 aptamer can promote targeted delivery of paclitaxel to allow targeted killing of CD133+ lung CSCs. N-Pac-CD133 loaded with paclitaxel may provide an effective treatment for lung cancer by targeting the lung cancer stem cells.


Subject(s)
Animals , Cell Line, Tumor , Drug Carriers , Lung , Mice , Mice, SCID , Nanoparticles , Neoplasms , Neoplastic Stem Cells , Paclitaxel/pharmacology , Polyethylene Glycols/pharmacology
16.
Braz. j. biol ; 82: e257622, 2022. tab, graf, ilus
Article in English | LILACS, VETINDEX | ID: biblio-1364492

ABSTRACT

Greeen synthesis has been introduced as an alternative to chemical synthesis due to the serious consequences. Metal nanoparticles synthesized through green approach have different pharmaceutical, medical and agricultural applications. The present study followed a green and simple route for the preparation of potentially bioactive gold nanoparticles (Au NPs). Au NPs were prepared via green synthesis approach using crude basic alkaloidal portion of the tuber of Delphinium chitralense. The green synthesized Au NPs were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD) fourier transform infrared (FTIR), and UV-Visible spectrophotometer. Morphological analysis shows that Au NPs have cubic geometry with different sizes. UV-Vis spectroscopic analysis confirmed the synthesis of Au NPs while XRD proved their pure crystalline phase. The Au NPs showed promising dose dependent inhibition of both AChE and BChE as compared to the crude as well as standard drug.


A síntese verde foi introduzida como uma alternativa à síntese química devido às graves consequências. As nanopartículas metálicas sintetizadas através da abordagem verde têm diferentes aplicações farmacêuticas, médicas e agrícolas. O presente estudo seguiu uma rota verde e simples para a preparação de nanopartículas de ouro potencialmente bioativas (Au NPs). As NPs de Au foram preparadas via abordagem de síntese verde usando a porção alcaloide básica bruta do tubérculo de Delphinium chitralense. As NPs de Au sintetizadas verdes foram caracterizadas por microscopia eletrônica de transmissão (TEM), microscopia eletrônica de varredura (MEV), difração de raios X (DRX), infravermelho com transformada de Fourier (FTIR) e espectrofotômetro UV-Visível. A análise morfológica mostra que as NPs de Au possuem geometria cúbica com tamanhos diferentes. A análise espectroscópica UV-Vis confirmou a síntese de Au NPs enquanto a XRD provou sua fase cristalina pura. O Au NPs mostrou inibição dependente da dose promissora de AChE e BChE em comparação com a droga bruta e padrão.


Subject(s)
Delphinium , Plant Tubers , Enzymes , Nanoparticles , Gold
17.
Article in Chinese | WPRIM | ID: wpr-940989

ABSTRACT

OBJECTIVE@#To explore the effects of oral exposure to titanium dioxide nanoparticles (TiO2 NPs) on the composition and structure of human gut microbiota.@*METHODS@#The particle size, shape, crystal shape and degree of agglomeration in ultrapure water of TiO2 NPs were characterized. The in vitro human digestive tract microecological simulation system was established by simulating the fluid environment and physical conditions of stomach, small intestine and colon, and the stability of the simulation system was evaluated. The bacterial communities were extracted from human feces and cultured stably in the simulated system. They were exposed to 0, 20, 100 and 500 mg/L TiO2 NPs, respectively, and the bacterial fluids were collected after 24 h of exposure. The effect of TiO2 NPs on the composition and structure of human gut microbiota was analyzed by 16S rRNA sequencing technology. Linear discriminant analysis effect size (LEfSe) was used to screen differential bacteria, and the Kyoto encyclopedia of genes and genomes (KEGG) database for functional prediction.@*RESULTS@#The spherical and anatase TiO2 NPs were (25.12±5.64) nm in particle size, while in ultra-pure water hydrated particle size was (609.43±60.35) nm and Zeta potential was (-8.33±0.22) mV. The in vitro digestive tract microecology simulation system reached a relatively stable state after 24 hours, and the counts of Enterococci, Enterobacte-rium, and Lactobacillus reached (1.6±0.85)×107, (5.6±0.82)×107 and (2.7±1.32)×107, respectively. 16S rRNA sequencing results showed that compared with the control group, the number and evenness of gut microbiota were not significantly affected at phylum, class, order, family and genus levels in TiO2 NPs groups (20, 100 and 500 mg/L). The relative abundance of some species was significantly changed, and a total of 42 different bacteria were screened between the TiO2 NPs groups (20, 100 and 500 mg/L) and the control group [linear discriminant analysis(LDA) score>3], represented by Enterobacter, Bacteroidaceae, Lactobacillaceae, Bifidobacteriaceae and Clostridium. Further predictive analysis of gut microbiota function showed that TiO2 NPs might affect oxidative phosphorylation, energy meta-bolism, phosphonate and phosphonate metabolism, and methane metabolism (P < 0.05).@*CONCLUSION@#In human digestive tract microecological simulation system, TiO2 NPs could significantly change the composition and structure of human gut microbiota, represented by Enterobacter and probiotics, and may further affect a variety of metabolism and function of the body.


Subject(s)
Bacteria/genetics , Gastrointestinal Microbiome , Gastrointestinal Tract , Humans , Nanoparticles , Organophosphonates/pharmacology , RNA, Ribosomal, 16S , Titanium/pharmacology , Water/pharmacology
18.
Article in English | WPRIM | ID: wpr-929151

ABSTRACT

The significant clinical feature of bisphosphonate-related osteonecrosis of the jaw (BRONJ) is the exposure of the necrotic jaw. Other clinical manifestations include jaw pain, swelling, abscess, and skin fistula, which seriously affect the patients' life, and there is no radical cure. Thus, new methods need to be found to prevent the occurrence of BRONJ. Here, a novel nanoparticle, tFNA-KLT, was successfully synthesized by us, in which the nanoparticle tetrahedral framework nucleic acid (tFNA) was used for carrying angiogenic peptide, KLT, and then further enhanced angiogenesis. TFNA-KLT possessed the same characteristics as tFNA, such as simple synthesis, stable structure, and good biocompatibility. Meanwhile, tFNA enhanced the stability of KLT and carried more KLT to interact with endothelial cells. First, it was confirmed that tFNA-KLT had the superior angiogenic ability to tFNA and KLT both in vitro and in vivo. Then we apply tFNA-KLT to the prevention of BRONJ. The results showed that tFNA-KLT can effectively prevent the occurrence of BRONJ by accelerating angiogenesis. In summary, the prepared novel nanoparticle, tFNA-KLT, was firstly synthesized by us. It was also firstly confirmed by us that tFNA-KLT significantly enhanced angiogenesis and can effectively prevent the occurrence of BRONJ by accelerating angiogenesis, thus providing a new avenue for the prevention of BRONJ and a new choice for therapeutic angiogenesis.


Subject(s)
Angiogenic Proteins/therapeutic use , Bisphosphonate-Associated Osteonecrosis of the Jaw/prevention & control , Endothelial Cells , Humans , Nanoparticles , Nucleic Acids/therapeutic use
19.
Article in Chinese | WPRIM | ID: wpr-928237

ABSTRACT

This study aims to explore the potential of polyaspartic acid grafted dopamine copolymer (PAsp- g-DA) chelated Fe 3+ for magnetic resonance imaging (MRI) visual photothermal therapy. Polyaspartic acid grafted copolymer of covalently grafted dopamine and polyethylene glycol (PAsp- g-DA/PEG) was obtained by the ammonolysis reaction of poly succinimide (PSI), and then chelated with Fe 3+ in aqueous solution. The relaxivity in vitro, magnetic resonance imaging enhancement in vivo and photothermal conversion effect at 808 nm were investigated. The results showed that polymeric iron coordination had good near-infrared absorption and photothermal conversion properties, good magnetic resonance enhancement effect, and good longitudinal relaxation efficiency under different magnetic field intensities. In summary, this study provides a new magnetic resonance visual photothermal therapeutic agent and a new research idea for the research in related fields.


Subject(s)
Dopamine , Magnetic Resonance Imaging/methods , Nanoparticles , Peptides , Phototherapy , Photothermal Therapy , Polymers
20.
Article in Chinese | WPRIM | ID: wpr-928125

ABSTRACT

In view of the longevity and innate immune escape of red blood cells, this study designed the red blood cell membrane-coated paclitaxel nanosuspension [RBC-(PTX)NS] and investigated its physicochemical properties and antitumor effect in vitro. Paclitaxel nanosuspension [(PTX)NS] was prepared by ultrasonic precipitation and then RBC-(PTX)NS by ultrasonic coating. The formulation of(PTX)NS was optimized with Box-Behnken method and indexes of particle diameter, zeta potential, and stability. The morphology, particle diameter, stability, in vitro dissolution, and antitumor effect of(PTX)NS and RBC-(PTX)NS were characterized. The results showed that the particle diameter and zeta potential were(129.38±0.92) nm and(-22.41±0.48) mV, respectively, for the optimized(PTX)NS, while(142.5±0.68) nm and(-29.85±0.53) mV, respectively, for RBC-(PTX)NS. Under the transmission electron microscope,(PTX)NS was spherical and RBC-(PTX)NS had obvious core-shell structure. RBC-(PTX)NS remained stable for 5 days at 4 ℃. The in vitro dissolution test demonstrated that the cumulative release rate of RBC-(PTX)NS reached 79% within 20 min, which was significantly higher than that(25%) of(PTX)NS(P<0.05). As evidenced by MTT assay, RBC-(PTX)NS highly inhibited the proliferation of HepG2 cells in a dose-dependent manner. The cell membrane-coated nano-preparation preparation method is simple and reproducible. It improves the solubility of PTX and endows RBC-(PTX)NS with higher stability and stronger cytotoxicity. Thus, it is a new method for the delivery of PTX via nanocrystallization.


Subject(s)
Erythrocyte Membrane , Nanoparticles/chemistry , Paclitaxel/pharmacology , Particle Size , Suspensions
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