RESUMO
The aim of this in vitro study was to evaluate the influence of treatment time on the remineralization performance of nanoencapsulated fluoride dentifrices on initial carious lesions. Ninety-six human enamel samples were allocated to eight groups (n = 12): 50% NanoF + 50% free NaF, 100% NanoF, 100% NaF (positive control), and placebo (negative control), using two different treatment times (one and five minutes) for each dentifrice tested. After the carious lesion induction, the specimens were submitted to a pH remineralizing cycling model for seven days. Surface microhardness was measured before and after carious lesion induction and after treatment. The percentage of surface remineralization was calculated for each study time. Data were analyzed using two-way ANOVA and ANOVA repeated-measures tests followed by the Bonferroni correction (p < 0.05). Remineralization differences were observed in the dentifrices analyzed according to the treatment time used. NanoF formulations with 50% (one-min treatment) and 100% (five-min treatment) promoted significant remineralization of enamel after the caries challenge when compared to the placebo dentifrice (p < 0.05). Thus, time was considered an important factor for the fluoride release system. Nanotechnology can be a promising system for caries remineralization as it makes fluoride available on the dental surface for a longer time.
O objetivo deste estudo in vitro foi de avaliar a influência do tempo de tratamento no desempenho de dentifrícios fluoretados nano-encapsulados na remineralização de lesões cariosas iniciais. Noventa e seis amostras de esmalte humano foram divididas em oito grupos (n = 12): 50% NanoF + 50% NaF livre, 100% NanoF, 100% NaF (controle positivo) e Placebo (controle negativo) com dois tempos diferentes (um e cinco minutos). Após a indução da lesão cariosa, os espécimes foram submetidos a um modelo de ciclagem de pH por sete dias. A microdureza superficial foi medida antes e após a indução da lesão cariosa e após o tratamento. O percentual de remineralização superficial foi calculado para cada tempo de estudo. Os dados foram analisados pelo ANOVA e ANOVA de medidas repetidas, seguida de Bonferroni (p <0,05). Diferenças de remineralização foram observadas nos dentifrícios de acordo com o tempo de tratamento utilizado. Formulações NanoF com 50% (tratamento de um minuto) e 100% (tratamento de cinco minutos) promoveram uma remineralização do esmalte, após o desafio cariogênico, quando comparado com o dentifrício placebo (p <0,05). Assim, o tempo foi considerado um fator importante para o sistema de liberação de flúor. A nanotecnologia pode ser um sistema promissor de remineralização da cárie, por disponibilizar o flúor por maior tempo na superfície dentária.
Assuntos
Cárie Dentária , Dentifrícios , Cariostáticos , Cárie Dentária/tratamento farmacológico , Dentifrícios/uso terapêutico , Fluoretos , Humanos , Concentração de Íons de Hidrogênio , Remineralização DentáriaRESUMO
ABSTRACT The aim of this in vitro study was to evaluate the influence of treatment time on the remineralization performance of nanoencapsulated fluoride dentifrices on initial carious lesions. Ninety-six human enamel samples were allocated to eight groups (n = 12): 50% NanoF + 50% free NaF, 100% NanoF, 100% NaF (positive control), and placebo (negative control), using two different treatment times (one and five minutes) for each dentifrice tested. After the carious lesion induction, the specimens were submitted to a pH remineralizing cycling model for seven days. Surface microhardness was measured before and after carious lesion induction and after treatment. The percentage of surface remineralization was calculated for each study time. Data were analyzed using two-way ANOVA and ANOVA repeated-measures tests followed by the Bonferroni correction (p < 0.05). Remineralization differences were observed in the dentifrices analyzed according to the treatment time used. NanoF formulations with 50% (one-min treatment) and 100% (five-min treatment) promoted significant remineralization of enamel after the caries challenge when compared to the placebo dentifrice (p < 0.05). Thus, time was considered an important factor for the fluoride release system. Nanotechnology can be a promising system for caries remineralization as it makes fluoride available on the dental surface for a longer time.
RESUMO O objetivo deste estudo in vitro foi de avaliar a influencia do tempo de tratamento no desempenho de dentifrícios fluoretados nano-encapsulados na remineralizagao de lesoes cariosas iniciáis. Noventa e seis amostras de esmalte humano foram divididas em oito grupos (n = 12): 50% NanoF + 50% NaF livre, 100% NanoF, 100% NaF (controle positivo) e Placebo (controle negativo) com dois tempos diferentes (um e cinco minutos). Após a indugao da lesao cariosa, os espécimes foram submetidos a um modelo de ciclagem de pH por sete dias. A microdureza superficial foi medida antes e após a indugao da lesao cariosa e após o tratamento. O percentual de remineralizagao superficial foi calculado para cada tempo de estudo. Os dados foram analisados pelo ANOVA e ANOVA de medidas repetidas, seguida de Bonferroni (p <0,05). Diferengas de remineralizagao foram observadas nos dentifrícios de acordo com o tempo de tratamento utilizado. Formulagoes NanoF com 50% (tratamento de um minuto) e 100% (tratamento de cinco minutos) promoveram uma remineralizagao do esmalte, após o desafio cariogènico, quando comparado com o dentifricio placebo (p <0,05). Assim, o tempo foi considerado um fator importante para o sistema de liberagao de flúor. A nanotecnologia pode ser um sistema promissor de remineralizagao da cárie, por disponibilizar o flúor por maior tempo na superficie dentària.
RESUMO
This study aimed to evaluate the in vitro activity of the crude extracts obtained from Caesalpinia ferrea Mart. (Jucá), Cinnamomum cassia B. (Cinnamon), Mallow sylvestris L. (Mallow), Punica granatum L. (Pomegranate), Rosmarinus officinalis L. (Rosemary), Aeolanthus suaveolens (Als.) Spreng. (Macassá), Sysygium aromaticum L. (Clove), and Tamarindus indica L. (Tamarind) against oral microorganisms (e.g., Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, and Parvimonas micra) that produce volatile sulfur compounds (VSC). The pure extracts were placed in culture medium for the diffusion test in agar. The Minimum Inhibitory Concentration (MIC) was determined by the microdilution method, and microbial growth was assayed with resazurin. Total polyphenols in the extracts were measured by using the Prussian Blue Method. For the salivary sediment test, the sediments were exposed to the Jucá and Pomegranate extracts, which was followed by incubation and organoleptic measurements with a monitor (Halimeter®) at 1-, 2-, 4-, and 24â¯-h intervals. The diffusion test revealed mixed results for the extracts. When the zone of inhibition was present, it ranged from 1.6-10.3â¯mm. The Pomegranate extract was the only extract that inhibited all the evaluated microorganisms; the MIC values ranged from 50 to 400⯵g/mL. The Pomegranate and Jucá extracts presented higher levels of polyphenols, 7.3 % and 3.9 %, respectively, and less VSC formation as compared to the negative control. In conclusion, the extracts display antimicrobial activity against the tested microorganisms. The investigated plants have the potential to reduce the main substances related to halitosis of oral origin.
Assuntos
Antibacterianos , Halitose , Extratos Vegetais , Plantas Medicinais , Prevotella intermedia , Halitose/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana , Extratos Vegetais/farmacologiaRESUMO
The bioassay-guided fractionation of the ethyl acetate extract of the fungus Cochliobolus sp. highlighted leishmanicidal activity and allowed for anhydrocochlioquinone A (ANDC-A) isolation. MS, 1D and 2D NMR spectra of this compound were in agreement with those published in the literature. ANDC-A exhibited leishmanicidal activity with EC 50 value of 22.4 microgram/mL (44 mu M) and, when submitted to the microdilution assay against Gram-ositive and Gram-negative bacteria, showed a minimal inhibitory concentration against Staphylococcus aureus ATCC 25295 of 128 microgram/mL (248.7 mu M). It was also active against five human cancer cell lines, showing IC50 values from 5.4 to 20.3 mu M. ANDC-A demonstrated a differential selectivity for HL-60 (SI 5.5) and THP-1 (SI 4.3) cell lines in comparison with Vero cells and was more selective than cisplatin and doxorubicin against MCF-7 cell line in comparison with human peripheral blood mononuclear cells. ANDC-A was able to eradicate clonogenic tumour cells at concentrations of 20 and 50 mu M and induced apoptosis in all tumour cell lines at 20 mu M. These results suggest that ANDC-A might be used as a biochemical tool in the study of tumour cells biochemistry as well as an anticancer agent with durable effects on tumours.
Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antiprotozoários/farmacologia , Ascomicetos/química , Benzoquinonas/farmacologia , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Ascomicetos/metabolismo , Benzoquinonas/química , Benzoquinonas/isolamento & purificação , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Células HCT116 , Células HL-60 , Humanos , Células Jurkat , Klebsiella oxytoca/efeitos dos fármacos , Klebsiella oxytoca/crescimento & desenvolvimento , Leishmania mexicana/efeitos dos fármacos , Leishmania mexicana/crescimento & desenvolvimento , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Células MCF-7 , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Células THP-1 , Células VeroRESUMO
The purpose of this study was to evaluate the antimicrobial properties of a new formulation containing silver nanoparticles, named Nano Silver Fluoride (NSF), to inhibit Streptococcus mutans biofilm formation on children's dental enamel. The variations in dental biofilm pH and in the Simplified-Oral-Hygiene-Index (OHI-S) also were evaluated after the treatment with NSF. This was a randomized, double-blind, crossover and prospective pilot clinical trial study in which 12 schoolchildren, aged between 7-8 years, had their dental enamel treated with two solutions: S1 - Nano Silver Fluoride and S2 - negative control (saline solution), in different experimental moments. The dental biofilm adhered to enamel treated with NSF had lower values of S. mutans viability (absorbance) and colony forming units (CFU) than the S0 (baseline) and S2. There was a statistically significant difference between the OHI-S mean values of S0 and S1. There were no differences between the biofilm pH (both before and after the use of the test substances) and among the different groups. These properties suggest that NSF has bactericidal effect against S. mutans biofilm and it may be used for clinical control and prevention of dental biofilm formation.
Assuntos
Biofilmes , Nanopartículas Metálicas , Prata/química , Streptococcus mutans/efeitos dos fármacos , Criança , Contagem de Colônia Microbiana , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Nanopartículas Metálicas/química , Índice de Higiene Oral , Projetos Piloto , Estudos Prospectivos , Streptococcus mutans/fisiologiaRESUMO
Abstract: The purpose of this study was to evaluate the antimicrobial properties of a new formulation containing silver nanoparticles, named Nano Silver Fluoride (NSF), to inhibit Streptococcus mutans biofilm formation on children's dental enamel. The variations in dental biofilm pH and in the Simplified-Oral-Hygiene-Index (OHI-S) also were evaluated after the treatment with NSF. This was a randomized, double-blind, crossover and prospective pilot clinical trial study in which 12 schoolchildren, aged between 7-8 years, had their dental enamel treated with two solutions: S1 - Nano Silver Fluoride and S2 - negative control (saline solution), in different experimental moments. The dental biofilm adhered to enamel treated with NSF had lower values of S. mutans viability (absorbance) and colony forming units (CFU) than the S0 (baseline) and S2. There was a statistically significant difference between the OHI-S mean values of S0 and S1. There were no differences between the biofilm pH (both before and after the use of the test substances) and among the different groups. These properties suggest that NSF has bactericidal effect against S. mutans biofilm and it may be used for clinical control and prevention of dental biofilm formation.
Resumo O objetivo do presente estudo foi avaliar as propriedades antimicrobianas de uma nova formulação composta por nanopartículas de prata, denominada nano silver fluoride (NSF), na inibição de biofilme de Streptococcus mutans sobre a superfície do esmalte dentário de crianças. Variações no pH do biofilme dental e nos valores do índice de Higiene Oral Simplificada (IHO-S) também foram avaliadas após o tratamento com NSF. Trata-se de um estudo piloto, randomizado, duplo cego, cruzado e prospectivo. A amostra foi composta por 12 crianças, de ambos os gêneros, com idades entre 7 e 8 anos, as quais utilizaram as duas soluções testes, S1- NSF e S2- controle negativo (solução salina). O biofilme dental tratado com NSF apresentou menores valores de viabilidade de S. mutans (absorbância) e de unidades formadoras de colônias (UFC) do que o biofilme baseline e o biofilme tratado com S2. Houve diferença estatisticamente significativa entre os valores médios de IHO-S dos grupos baseline e S1, com uma redução dos valores. Não houve qualquer variação nos valores de pH do biofilme dental, antes e depois do tratamento com S1 e S2 e entre os diferentes grupos. Estas propriedades sugerem que NSF possui efeito bactericida sobre o biofilme de S. mutans, podendo ser utilizado clinicamente para o controle e prevenção da formação do biofilme dentário.
Assuntos
Humanos , Masculino , Feminino , Criança , Biofilmes , Nanopartículas Metálicas/química , Prata/química , Streptococcus mutans/efeitos dos fármacos , Contagem de Colônia Microbiana , Estudos Cross-Over , Método Duplo-Cego , Concentração de Íons de Hidrogênio , Índice de Higiene Oral , Projetos Piloto , Estudos Prospectivos , Streptococcus mutans/fisiologiaRESUMO
The present study aimed to evaluate the antimicrobial activity and cytotoxicity of colloidal chitosan - silver nanoparticle - fluoride nanocomposites (CChAgNpFNc), with different silver nanoparticle shapes and sizes. The syntheses of CChAgNpFNc were performed with silver nitrate added to a chitosan solution, addition of a sodium borohydride solution and solid sodium fluoride. Solution of ascorbic acid was added to synthesize larger silver nanoparticles. CChAgNpFNc obtained: S1- 100% spherical, 8.7±3.1nm; S2- 97% spherical, 15.0±7.9nm and 2.5% triangular, 22.2±9.5nm; S3- 77.3% spherical, 31.8±10.4nm, 15.9% triangular, 27.1±10.1nm and 6.8% elliptical, 33.2±7.8nm; and S4- 75.2% spherical, 43.2±14.3nm; 23.3% triangular 38.2±14.8nm, and 1.5% elliptical 38.4±11.6nm. The CChAgNpFNc showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans, by microdilution technique. The influence on the growth of microorganisms was evaluated using a fluorescence assay, and showed an increasing lag phase and a decreasing log phase. Cytotoxicity was investigated using Artemia salina and MTT assays. The S3 and S4 samples exhibited low cytotoxicity. The S1 and S2 samples inhibited murine macrophages and revealed lethal dose concentrations above 1000mg/mL that were classified as moderately toxic. Thus, CChAgNpFNc are potential options for the control of multiple-drug-resistant microorganisms and do not represent substantial risks to human health.
Assuntos
Antibacterianos/farmacologia , Quitosana/química , Fluoretos/farmacologia , Nanopartículas Metálicas/toxicidade , Nanocompostos/toxicidade , Animais , Antibacterianos/química , Candida albicans/efeitos dos fármacos , Linhagem Celular Tumoral , Coloides , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fluoretos/química , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Camundongos , Testes de Sensibilidade Microbiana , Nanocompostos/química , Nanocompostos/ultraestrutura , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Células RAW 264.7 , Staphylococcus aureus/efeitos dos fármacosRESUMO
UNLABELLED: The role of dentin cleaning is to remove debris that may impair adaptation and marginal sealing, quantitatively reducing microorganisms. The aim of this study was to investigate through scanning electron microscopy (SEM) the morphology of the dentin surface, cut and treated with copaiba oil emulsions (CO) and suspension of ethanol extract of propolis (EP). Twenty four upper pre-molars teeth, divided into eight groups (n=3), were used: G1: no cleaning, G2: air/water spray, G3: 10% CO, G4: 10% CO + A, G5: 30% CO, G6: 30% CO + A, G7: 1% EP, G8: 2% Chlorhexidine. The specimens were dentin discs (1 mm Ø). The SEM photomicrographs were classified and the results were: G1 - Debris dentin on the entire image / countless microorganisms, G2 and G7 - 50-100 debris / countless microorganisms and G3, G4, G5, G6 and G8 - 0-50 debris / countable microorganisms (50-100 colonies). CONCLUSION: The present results suggest that copaiba oil emulsions (CO) and suspension of ethanol extract of propolis (EP) have feasibility to be used as bioactive dental cleaning agents.
RESUMO
In this study poly(lactic acid) (PLA) and polyvinylpyrrolidone (PVP) micro- and nanofiber mats loaded with Copaiba (Copaifera sp.) oil were produced by solution blow spinning (SBS). The Copaiba (Copaifera sp.) oil was characterized by gas chromatography (GC). Neat PLA and four PLA/PVP blends containing 20% (wt.%) oil were spun and characterized by scanning electron microscopy (SEM) and by studying the surface contact angle, in vitro release rate, and antimicrobial activity. All compositions evaluated were able to produce continuous and smooth fibers by SBS. The addition of PVP increased fiber diameter, and decreased the surface contact angle. GC analysis demonstrated that the main component of the Copaiba oil was ß-caryophyllene, a known antimicrobial agent. In vitro release tests of Copaiba oil volatiles demonstrated a higher release rate in fibers containing PVP. Fiber mats made from blends containing higher amounts of PVP had greater antimicrobial action against Staphylococcus aureus. The results confirm the potential of the fiber mats for use in controlled drug release and could lead to promising applications in the biomedical field.
Assuntos
Anti-Infecciosos , Fabaceae/química , Ácido Láctico , Nanofibras/química , Óleos de Plantas , Polímeros , Povidona/análogos & derivados , Staphylococcus aureus/crescimento & desenvolvimento , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Ácido Láctico/química , Ácido Láctico/farmacologia , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Poliésteres , Polímeros/química , Polímeros/farmacologia , Povidona/química , Povidona/farmacologiaRESUMO
Multidrug-resistant Salmonella enterica isolates from human outbreaks or from poultry origin were investigated for their ability to develop direct-tolerance or cross-tolerance to sodium chloride, potassium chloride, lactic acid, acetic acid, and ciprofloxacin after habituation in subinhibitory amounts ( of the minimum inhibitory concentration - (MIC) and of the minimum inhibitory concentration - MIC) of Origanum vulgare L. essential oil (OVEO) at different time intervals. The habituation of S. enterica to OVEO did not induce direct-tolerance or cross-tolerance in the tested strains, as assessed by the modulation of MIC values. However, cells habituated to OVEO maintained or increased susceptibility to the tested antimicrobials agents, with up to fourfold double dilution decrease from previously determined MIC values. This study reports for the first time the non-inductive effect of OVEO on the acquisition of direct-tolerance or cross-tolerance in multidrug-resistant S. enterica strains to antimicrobial agents that are largely used in food preservation, as well as to CIP, the therapeutic drug of salmonellosis.