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1.
Braz. j. biol ; 83: e245807, 2023. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1285613

ABSTRACT

Abstract Linum usitatissimum L is a widely used traditionally for multiple ailments. The present research was carried out to explore the antimicrobial, and anti-biofilm activity of crude extract of Linum usitatissimum L (Lu. Cr). Phytochemical and proximate analyses were performed. The bandages of diabetic foot patients were collected from the various hospitals. The bandages were cultured to isolate the bacterial strains present on it. The disc diffusion method was used to identify the antimicrobial potential whereas the minimum inhibitory concentration of the Lu.Cr were also determined. Proximate analysis confirms moisture content 8.33%, ash content 4.33%, crude protein 21.20%, crude fat 49.2% and crude fiber 5.63%. It was revealed that Gram-positive bacteria are most prevalent among all study groups. Lu.Cr possess significant bactericidal potential against S. aureus among all other microbes. Owing to this potential, linseed coated bandages can be used alternatively for the treatment of diabetic foot.


Resumo Linum usitatissimum L é amplamente utilizado tradicionalmente para doenças múltiplas. O presente trabalho foi realizado para explorar a atividade antimicrobiana e antibiofilme do extrato bruto de Linum usitatissimum L (Lu.Cr). Foram realizadas análises fitoquímicas e aproximadas. As ataduras de pacientes diabéticos com pé foram recolhidas nos vários hospitais. As bandagens foram cultivadas para isolar as cepas bacterianas presentes nas mesmas. O método de difusão em disco foi utilizado para identificar o potencial antimicrobiano e a concentração inibitória mínima do Lu.Cr também foi determinada. A análise aproximada confirma o teor de umidade 8,33%, teor de cinzas 4,33%, proteína bruta 21,20%, gordura bruta 49,2% e fibra bruta 5,63%. Foi revelado que as bactérias Gram-positivas são mais prevalentes entre todos os grupos de estudo. Lu.Cr possui potencial bactericida significativo contra S. aureus entre todos os outros micróbios. Devido a esse potencial, as ligaduras revestidas com linhaça podem ser utilizadas alternativamente para o tratamento do pé diabético.


Subject(s)
Humans , Diabetic Foot/drug therapy , Flax , Diabetes Mellitus , Staphylococcus aureus , Plant Extracts/pharmacology , Microbial Sensitivity Tests , Biofilms , Methanol
2.
ABCS health sci ; 47: e022203, 06 abr. 2022. tab, graf
Article in English | LILACS | ID: biblio-1363538

ABSTRACT

INTRODUCTION: Contamination of cell phones can contribute to the dissemination of pathogens in the community and/or hospital environment. OBJECTIVE: To characterize Staphylococcus aureus strains isolated from cell phones of university students. METHODS: Samples were collected from 100 cell phones. Detection of genes associated with virulence factors such as biofilm formation (icaA and icaD), enterotoxins production (SEA, SEB, SEC, and SED), and resistance to methicillin (mecA and mecC) was performed in S. aureus isolates by PCR. Typing mecA gene performed by multiplex PCR. Susceptibility to antimicrobials and biofilm formation rate also evaluated by using disk diffusion test and crystal violet staining. RESULTS: S. aureus was present in 40% of the total samples and about 70% of them belonged to Nursing students. Of the isolates, 85% presented resistance to penicillin and 50% were classified as moderate biofilm producers. In addition, 92.5% of isolates contained the gene icaA and 60% of the gene icaD. Approximately 25% of the isolates presented the mecA gene. Typing of the mecA gene showed the presence of staphylococcal chromosome cassette SCCmec I and c III respectively in 20% and 10% of the isolates. 70% of the samples could not be typed by the technique. Regarding the enterotoxins, the most prevalent gene was SEA (30%) followed by the SEC gene (2.5%). The presence of SED and SEB genes not observed in any of the isolates. CONCLUSION: The cleaning and periodic disinfection of cell phones can contribute to the reduction of the risk of nosocomial infection.


INTRODUÇÃO: A contaminação de celulares pode contribuir para a disseminação de patógenos na comunidade e/ou ambiente hospitalar. OBJETIVO: Caracterizar cepas de Staphylococcus aureus de telefones celulares de estudantes universitários. MÉTODOS: Foram coletadas amostras de 100 telefones celulares. Detecção de genes associados a fatores de virulência quanto a: formação de biofilme (icaA e icaD), produção de enterotoxinas (SEA, SEB, SEC e SED) e resistência à meticilina (mecA e mecC) foi realizada em isolados de S. aureus por PCR. A Tipagem do gene mecA foi realizada por PCR multiplex. A susceptibilidade a antimicrobianos e a taxa de formação de biofilme pelo teste de difusão em disco e coloração com cristal violeta. RESULTADOS: S. aureus esteve presente em 40% do total de amostras, destas, 70% pertenciam a estudantes do curso de enfermagem. Dos isolados, 85% apresentaram resistência à penicilina e 50% foram classificados com moderada formação de biofilme. Além disso, 92,5% dos isolados continham o gene icaA e 60% o gene icaD. Aproximadamente 25% dos isolados apresentaram o gene mecA. A tipagem do gene mecA mostrou a presença do cassete cromossômico estafilocócico SSCmec I e III em respectivamente 20% e 10% dos isolados. 70% das amostras não puderam ser identificadas pela técnica. Das enterotoxinas, o gene mais prevalente foi o SEA (30%), seguido pelo gene SEC (2.5%). A presença dos genes SED e SEB não foi observada nos isolados. CONCLUSÃO: A limpeza e desinfecção periódica dos telefones celulares podem contribuir para a redução do risco de infecção nosocomiais.


Subject(s)
Students, Health Occupations , Universities , Cell Phone , Methicillin-Resistant Staphylococcus aureus , Virulence , Drug Resistance, Microbial , Biofilms , Enterotoxins
3.
Braz. j. biol ; 82: e239991, 2022. tab, graf
Article in English | MEDLINE, LILACS, VETINDEX | ID: biblio-1278503

ABSTRACT

Abstract High resistance to antimicrobials is associated with biofilm formation responsible for infectious microbes to withstand severe conditions. Therefore, new alternatives are necessary as biofilm inhibitors to control infections. In this study, the antimicrobial and antibiofilm activities of Fagonia indica extracts were evaluated against MDR clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica has antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against multidrug resistant (MDR) clinical isolates. The extract exhibited its antibiofilm effect by altering adherence and disintegration of bacterial cell wall. Fagonia indica had antibacterial effect as minimum inhibitory concentration (MIC) values ranging from 125 to 500 µg mL-1 and minimum bactericidal concentration (MBC) value was 500-3000 µg mL-1 against MDR isolates. The maximum inhibitory effects of Fagonia indica chloroform extract on biofilm formation was observed on Staphylococcus aureus (71.84%) followed by Klebsiella pneumoniae (70.83%) after 48 hrs showing that inhibition is also time dependent. Our results about bacterial cell protein leakage indicated that MDR isolates treated with chloroform extract of Fagonia indica showed maximum protein leakage of K. pneumoniae (59.14 µg mL-1) followed by S. aureus (56.7 µg mL-1). Cell attachment assays indicated that chloroform extract resulted in a 43.5-53.5% inhibition of cell adherence to a polystyrene surface. Our results revealed that extracts of Fagonia indica significantly inhibited biofilm formation among MDR clinical isolates, therefore, could be applied as antimicrobial agents and cost effective biofilm inhibitor against these MDR isolates.


Resumo A alta resistência aos antimicrobianos está associada à formação de biofilme responsável por micróbios infecciosos para suportar condições severas. Portanto, novas alternativas são necessárias como inibidores de biofilme para controlar infecções. Neste estudo, as atividades antimicrobiana e antibiofilme dos extratos de Fagonia indica foram avaliadas contra isolados clínicos MDR. O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica tem efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e valor de concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados clínicos multirresistentes (MDR). O extrato exibiu seu efeito antibiofilme ao alterar a aderência e a desintegração da parede celular bacteriana. Fagonia indica teve efeito antibacteriano com valores de concentração inibitória mínima (CIM) variando de 125 a 500 µg mL-1, e concentração bactericida mínima (MBC) de 500-3000 µg mL-1 contra isolados MDR. Os efeitos inibitórios máximos do extrato de clorofórmio Fagonia indica na formação de biofilme foi observada em Staphylococcus aureus (71,84%), seguido por Klebsiella pneumoniae (70,83%) após 48 horas, mostrando que a inibição também é dependente do tempo. Nossos resultados sobre extravasamento de proteínas de células bacterianas indicaram que isolados MDR tratados com extrato clorofórmico de Fagonia indica apresentaram vazamento máximo de proteínas de K. pneumoniae (59,14 µg mL-1), seguido por S. aureus (56,7 µg mL-1). Ensaios de fixação de células indicaram que o extrato de clorofórmio resultou em uma inibição de 43,5-53,5% da aderência das células a uma superfície de poliestireno. Nossos resultados revelaram que extratos de Fagonia indica inibiram significativamente a formação de biofilme entre isolados clínicos MDR, portanto, poderiam ser aplicados como agentes antimicrobianos e inibidores de biofilme de baixo custo contra esses isolados MDR.


Subject(s)
Staphylococcus aureus , Plant Extracts/pharmacology , Bacteria , Microbial Sensitivity Tests , Biofilms , Drug Resistance, Multiple, Bacterial
4.
Braz. j. oral sci ; 20: e212098, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1281101

ABSTRACT

Aim: This study aimed to evaluate the pH, Ca2+ release, solubility, and antimicrobial activity of calcium hydroxide (Ca(OH)2) pastes in association with different substances. Methods: Sixty acrylic teeth (n=10) were filled with pastes that associated Ca(OH)2 with the following substances: benzalkonium chloride 5% (G1) and 50% (G2) both in propylene glycol, arnica glycolic extract (G3), green tea glycolic extract (G4), Calen/PMCC™ (G5), and Calen™ (G6). In the group G1 to G4 were used 1g of Ca(OH)2 powder with 0,8g of vehicle. pH and Ca2+ release was measured after 7, 15, and 30 days. For solubility, micro-CT was used immediately and at the periods of 7, 15, and 30 days. For the antimicrobial analysis, a biofilm of E. faecalis was induced in vitro on bovine dentin discs. Live/dead viability dye and confocal scanning microscopy were used. Results: The highest pH values occurred on the first 7 days, and the G6, G1, G3, and G5 presented the highest pH values at this period (P <0.05). Ca2+ release was higher in all groups at 7 days, with the highest values observed in G1, G5, and G6. The volume of all pastes showed no significant difference in the intragroup analysis at 7 and 15 days (P <0.05). G1 and G2 showed the highest antimicrobial action (P <0.05). For the biovolume, there was difference between the G6 and the other groups (P >0.05) with G1 presenting the lowest values. Conclusion: Benzalkonium chloride 5% increases the antimicrobial action of the Ca(OH2), without impairs physicochemical properties


Subject(s)
Root Canal Filling Materials , Calcium Hydroxide , Biofilms , Chemical Phenomena , Anti-Infective Agents
5.
Braz. j. oral sci ; 20: e211060, jan.-dez. 2021. ilus
Article in English | LILACS, BBO | ID: biblio-1254621

ABSTRACT

Aim: To evaluate the efficacy of ultrasonic bath and traditional brushing in the hygiene of complete dentures of dependent residents in long-term care institutions (LTCIs). Methods: A randomized cross-over clinical study was conducted in 17 maxillary complete denture wearers living in LTCIs. Cleaning protocols were brushing or ultrasonic bath, both applied with neutral liquid soap. Biofilm biomass were estimated by MTT reduction assay and specific microbial load (CFU) of Streptococcus spp., Staphylococcus spp. and Candida spp. were quantified by selective and differential culture media. Results: Ultrasound method showed higher percentage reduction of biofilm biomass and specific microbial loads of Streptococcus spp. compared to brushing (p<0.01). Reduction of microbial loads of the other microorganisms were not different between cleaning methods (p>0.05). Conclusions: The ultrasonic bath proved to be a feasible alternative method for the mechanical cleaning of complete dentures in LTCIs


Subject(s)
Aged , Hygiene , Dentures , Biofilms , Health Services for the Aged
6.
Braz. dent. j ; 32(4): 8-18, July-Aug. 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345521

ABSTRACT

Abstract The aim of this study was to evaluate the physicochemical properties, cytocompatibility and antibiofilm activity of a new calcium silicate-based endodontic sealer, Sealer Plus BC (MK Life, Brazil), in comparison with TotalFill BC Sealer (FKG Dentaire SA, Switzerland) and AH Plus (Dentsply, Germany). Setting time and flow were evaluated based on ISO 6876 standard. The pH was evaluated after different periods, and radiopacity by radiographic analysis (mmAl). Solubility (% mass loss) and volumetric change (by micro-CT) were assessed after 30 days of immersion in distilled water. Cytocompatibility was assessed by methyltetrazolium (MTT) and neutral red (NR) assays, after exposure of Saos-2 cells to the sealer extract for 24 h. An additional analysis was performed by using MTT assay after 1, 3 and 7 days of exposure of Saos-2 to the sealers 1:8 dilution extracts. Antibiofilm activity against Enterococcus faecalis and/or Candida albicans was evaluated by crystal violet assay and modified direct contact test. The physicochemical properties were analyzed using ANOVA/Tukey tests; MTT and NR data were analyzed by ANOVA and Bonferroni tests; the antimicrobial tests were analyzed by Kruskal-Wallis and Dunn tests (α=0.05). Sealer Plus BC had proper setting time, radiopacity, flow and alkalization capacity. Sealer Plus BC was significantly more soluble than AH Plus (p<0.05) and presented volumetric change similar to AH Plus and TotalFill BC (p>0.05). Sealer Plus BC presented antibiofilm activity and no cytotoxic effect. In conclusion, although Sealer Plus BC had higher solubility, this sealer showed proper physicochemical properties, cytocompatibility, and antibiofilm activity.


Resumo O objetivo deste estudo foi avaliar as propriedades físico-químicas, a citocompatibilidade e a atividade antibiofilme de um novo cimento endodôntico à base de silicato de cálcio, Sealer Plus BC (MK Life, Brasil), em comparação com TotalFill BC Sealer (FKG Dentaire SA, Suíça) e AH Plus (Dentsply, Alemanha). O tempo de presa e o escoamento foram avaliados com base nas normas ISO 6876. O pH foi avaliado após diferentes períodos, e a radiopacidade por análise radiográfica (mmAl). A solubilidade (% de perda de massa) e alteração volumétrica (por micro-CT) foram avaliadas após 30 dias de imersão em água destilada. Citocompatibilidade foi avaliada pelos ensaios metiltetrazólio (MTT) e vermelho neutro (NR), após exposição das células Saos-2 ao extrato de cimento por 24 horas. Análise adicional foi realizada através do ensaio MTT após 1, 3 e 7 dias de exposição das células Saos-2 aos extratos dos cimentos na diluição de 1:8. Atividade antibiofilme contra Enterococcus faecalis e/ou Candida albicans foi avaliada pelos ensaios cristal violeta e contato direto modificado. As propriedades físico-químicas foram analisadas utilizando os testes ANOVA e Tukey; MTT e NR foram analisados pelos testes ANOVA e Bonferroni; os ensaios antimicrobianos foram analisados pelos testes Kruskal-Wallis e Dunn (α=0.05). Sealer Plus BC apresentou tempo de presa, radiopacidade e escoamento adequados, além de capacidade de alcalinização. Sealer Plus BC foi significantemente mais solúvel que AH Plus (p<0.05) e apresentou alteração volumétrica similar à de AH Plus e TotalFill BC (p>0.05). Sealer Plus BC apresentou atividade antibiofilme, sem efeito citotóxico. Como conclusão, embora Sealer Plus BC apresente maior solubilidade, este cimento apresentou propriedades físico-químicas adequadas, citocompatibilidade e atividade antibiofilme.


Subject(s)
Root Canal Filling Materials/pharmacology , Materials Testing , Silicates/pharmacology , Calcium Compounds/pharmacology , Biofilms , Epoxy Resins
7.
Rev. ADM ; 78(4): 189-194, jul.-ago. 2021. ilus, tab
Article in Spanish | LILACS | ID: biblio-1292408

ABSTRACT

Introducción: La salud oral en pacientes con síndrome de Down (SD) es un reto, ya que las alteraciones en la motricidad ocasionadas por la discapacidad intelectual (DI) hacen que tareas como la remoción del biofilm oral o placa dentobacteriana (PDB) con el cepillado sea deficiente. La efectividad de los cepillos eléctricos (CE) comparada con los manuales (CM) en afectados con SD sigue siendo un tema debatible ya que no se ha encontrado una homogeneidad de resultados. Es conveniente mayor investigación sobre el tema, debido a que el SD es considerada la alteración cromosómica más frecuente y la causa principal de DI en el mundo. Objetivo: Conocer la efectividad del CE en comparación con el CM para la remoción de PDB en pacientes mexicanos con SD de entre seis y 14 años. Material y métodos: Estudio transversal experimental, con emparejamiento de sujetos con SD de ambos géneros según la edad (seis a 14 años), asignando el cepillo a utilizar (grupo 1 CM o grupo 2 CE). Se realizó educación dental y método de cepillado con la técnica de Fones, así como control de PDB antes y después el efectuado por medio del índice de O'Leary durante tres días. Se analizaron los resultados utilizando estadística descriptiva e inferencial (prueba de normalidad Lilliefors, prueba t para variables independientes y dependientes). Se aceptó un análisis de significancia p < 0.05. Resultados: La utilización de la t para muestras independientes presentó una mejoría en incremento de dicho marcador de O'Leary en el conjunto total en los tres días de seguimiento respectivamente (t = 6.9, p < 0.00002; t = 8.4, p < 0.00000; y t = 9.5, p < 0.00000). Al comparar por prueba t aplicada a muestras dependientes el índice de O'Leary basal versus cada una de las evaluaciones de seguimiento también se observaron diferencias significativas en los dos conjuntos (grupo 1: p = 0.003, p = 0.0006 y p = 0.0017; grupo 2: p = 0.007, p = 0.0006 y p = 0.0002). Conclusión: La instrucción dental y motivación del paciente fueron determinantes hacia el buen desempeño del cepillado de los dientes y remoción de placa en el par de colectivos, es decir, la reafirmación de la técnica de Fones incrementa gradualmente la mejoría de la forma de uso del cepillo en niños con SD. Ambos métodos con CM y con CE fueron efectivos a fin de remover significativamente la placa, observándose una mayor mejoría en el grupo con CE, sugiriendo que éste disminuye la dificultad de la higiene bucal en personas con SD. Esta línea de investigación es importante en el beneficio de la condición oral de esta población (AU)


Introduction: Oral health in patients having Down syndrome (DS) is a challenge since the changes in motor skills caused by intellectual disability (ID) deteriorate tasks such as the removal of biofilm or dental plaque (DP) with brushing. The effectiveness of electric toothbrushes (ET) compared to manual toothbrushes (MT) in DS patients remains debatable since no homogeneity of results has been found. Further research on the subject is advisable as DS is considered the most frequent chromosomal alteration and the leading cause of ID in the world. Objective: To know the effectiveness of the ET in contrast to the MT for the removal of DP in Mexican DS patients between six and 14 years old. Material and methods: Experimental cross-sectional study, with the pairing of DS subjects of both genders according to age (six to 14 years), assigning the brush to be used (group 1 MT or group 2 ET). Dental education and brushing were performed employing the Fones technique and DP control before and after brushing employing the O'Leary index for three days. The results were analyzed using descriptive and inferential statistics (Lilliefors normality test, t-test for independent and dependent variables). A significance test p < 0.05 was accepted. Results: The t-test for independent samples showed an improvement in the increase of the O'Leary index in the complete group in the three days of follow-up respectively (t = 6.9, p < 0.00002; t = 8.4, p < 0.00000; and t = 9.5, p < 0.00000). When comparing by t-test for dependent samples the baseline O'Leary index versus each of the follow-up evaluations, significant differences were also observed in both groups (group 1: p = 0.003, p = 0.0006 and p = 0.0017; group 2: p = 0.007, p = 0.0006 and p = 0.0002). Conclusion: The dental education and motivation of the patient were decisive for the good performance of tooth brushing and removal of the plaque in both groups. The reaffirmation of the Fones technique gradually increases the improvement of the brushing technique in DS children. Both brushings using MT and ET were effective in removing the biofilm significantly. However, a greater improvement was observed in the group with ET, suggesting that it reduces their difficulty with tooth brushing. This line of research is important to benefit the oral condition of this population (AU)


Subject(s)
Humans , Male , Female , Child , Adolescent , Toothbrushing , Dental Plaque Index , Down Syndrome , Dental Care for Disabled , Oral Hygiene , Effectiveness , Health Education, Dental , Cross-Sectional Studies , Statistical Analysis , Biofilms , Motor Skills
8.
Braz. dent. j ; 32(3): 10-20, May-June 2021. tab, graf
Article in English | LILACS, BBO | ID: biblio-1345504

ABSTRACT

Abstract The host defense response to microbial challenge emerging from the root canal system leads to apical periodontitis. The aim of this study was to evaluate the expression of inflammatory cytokines and Nitric Oxide (NO) by macrophages after interaction with Enterococcus faecalis in the: plankton and dislodged biofilm mode; intact biofilm mode stimulated by calcium hydroxide (CH), CH and chlorhexidine (CHX) or Triple Antibiotic Paste (TAP). For this purpose, culture of macrophages from monocytes in human peripheral blood (N=8) were exposed to the different modes of bacteria for 24 hours. Subsequently, the cytokines, such as, Tumor Necrotic Factor- alfa (TNF-α), interleukin (IL)-1β, IL-6, IL-10; and NO were quantified by Luminex xMAP and Greiss reaction, respectively. In addition to the potential therapeutic effects of the intracanal medication, their antimicrobial activity against Enterococcus faecalis biofilm were also tested in vitro by confocal microscopy. The experiments` data were analyzed by the Kruskal-Wallis test with the Dunn post hoc test (α < 0.05). Bacteria in dislodged biofilm mode were shown to be more aggressive to the immune system than bacteria in plankton mode and negative control, inducing greater expression of NO and TNF-α. Relative to bacteria in intact biofilm mode, the weakest antimicrobial activity occurred in Group CH. In Groups CH/CHX and TAP the percentage of dead bacteria was significantly increased to the same extent. Interestingly, the biofilm itself did not induce the release of pro-inflammatory cytokines - except for NO - while the biofilm treated with TAP and CH based pastes enhanced the levels of IL-6 and TNF-α; and IL-1 β, respectively. In contrast, the levels of a potent anti-inflammatory (IL-10) were increased in Group TAP.


Resumo A resposta de defesa do hospedeiro ao desafio microbiano que emerge do sistema de canais radiculares leva à periodontite apical. Os objetivos deste estudo foram avaliar a expressão de citocinas pró e anti-inflamatórias e Óxido Nítrico (NO) por macrófagos após interação com Enterococcus faecalis no modo: planctônio e de biofilme desalojado; biofilme intacto estimulado por hidróxido de cálcio (CH), CH e clorexidina ou Pasta Tri Antibiótica (TAP). Para isto, a cultura de macrófagos originados de monócitos do sangue periférico de humanos (N=8) foi exposta aos diferentes tipos de bactéria por 24 horas. Então, a quantificação da produção de of Fator de Necrose Tumoral- alfa (TNF-α), interleucina (IL)-1β, IL-6, IL-10 e NO por macrófagos se deu por meio do Luminex xMAP e reação de Greiss, respectivamente. Além dos potenciais efeitos terapêuticos desses compostos, sua atividade antimicrobiana contra E. faecalis também foi testada através microscopia confocal. Os dados dos experimentos foram analisados através do teste de Kruskal-Wallis com Dunn`s post hoc (α < 0.05). Bactéria em modo de biofilme desalojado se mostrou mais agressivo ao sistema imune que as bactérias planctônicas e controle negativo induzindo a maior excreção de NO e TNF-α. Em relação ao biofilme intacto, a atividade antimicrobiana mais fraca ocorreu no grupo de CH. Os grupos CHX e TAP aumentaram significativamente a porcentagem de bactérias mortas na mesma extensão. Interessantemente, o biofilme por ele mesmo não induziu a liberação de citocinas pro-inflamatórias - exceto por NO - enquanto que o biofilme tratado com TAP ou pastas a base de CH aumentaram os níveis de IL-6; e TNF-α e IL-1 β respectivamente. Em contraste, os níveis da potente citocina anti-inflamatória (IL-10) foram aumentados pelo grupo TAP.


Subject(s)
Humans , Plankton , Biofilms , Root Canal Irrigants , Bacteria , Calcium Hydroxide , Chlorhexidine , Enterococcus faecalis , Anti-Bacterial Agents
9.
Rev. epidemiol. controle infecç ; 11(2): [1-13], abr.-jun. 2021. ilus
Article in English | LILACS | ID: biblio-1362763

ABSTRACT

Justification and Objectives: Circulating blood is sterile and the presence of microorganisms can be of clinical interest, especially in the hospital environment, being able to cause infectious processes and substantially increase morbidity and mortality. The objective of this work was to characterize the isolates of the genus Staphylococcus spp. from bloodstream infections as to the production of bacterial biofilm and resistance to the main antimicrobials used in clinical practice. Methods: Blood cultures were collected with an indication of positivity for bacterial growth from multiple sectors of the study hospital, which were subsequently processed to identify the bacterial genus through the use of phenotypic tests for Gram positive bacteria. The verification of the resistance profile was performed following the Kirby-Bauer disk diffusion. The identification of the production and quantification of the bacterial biofilm occurred following the protocol described by O'toole (2010). Results: The most frequent clinical isolate was Coagulase negative Staphylococci 38 (54.29%), followed by Staphylococcus aureus 32 (45.71%). Resistance to erythromycin, norfloxacin, levofloxacin and azithromycin was observed in most isolates (70%). Regarding methicillin, more MRSA (59.38%) than MR-CONS (47.37%) were isolated. The ICU was the place where the formation of the biofilm showed indicative data of greater adherence, which was associated with MRSA strains. Conclusion: The bacterial isolates associated with bloodstream infections showed high resistance to antimicrobials. The presence of MRSA and MR-CONS with strong and/or moderate biofilm production capacity represents a greater risk to the health of patients affected by infections caused by these agents.(AU)


Justificativa e Objetivos: O sangue circulante é estéril e a presença de microrganismos pode ter interesse clínico, especialmente no ambiente hospitalar, sendo capaz de causar processos infecciosos e aumentar substancialmente a morbimortalidade. O objetivo deste trabalho foi caracterizar os isolados do gênero Staphylococcus spp. oriundos de infecções de corrente sanguínea quanto à produção de biofilme bacteriano e resistência aos principais antimicrobianos utilizados na prática clínica. Métodos: Foram coletadas hemoculturas com indicação de positividade para o crescimento bacteriano de múltiplos setores do hospital de estudo, as quais posteriormente foram processadas para identificação do gênero bacteriano através da utilização de testes fenotípicos para bactérias Gram positivas. A verificação do perfil de resistência foi realizada seguindo a metodologia de disco difusão de Kirby-Bauer. A identificação da produção e quantificação do biofilme bacteriano ocorreu seguindo o protocolo descrito por O'toole (2010). Resultados: O isolado clínico mais frequente foi o Staphylococcus coagulase negativo 38 (54,29%), seguido pelo Staphylococcus aureus 32 (45,71%). A resistência à eritromicina, norfloxacina, levofloxacina e azitromicina foi observada na maioria dos isolados (70%). Em relação à meticilina, foram isolados mais Staphylococcus aureus resistente à meticilina (MRSA) (59,38%) que Staphylococcus coagulase negativa resistente à meticilina (MR-CONS) (47,37%). A UTI foi o local onde a formação do biofilme apresentou dados indicativos de maior aderência, sendo essa associada às cepas MRSA. Conclusão: Os isolados bacterianos associados às infecções da corrente sanguínea apresentaram elevada resistência aos antimicrobianos. A presença de MRSA e MR-CONS com forte e/ou moderada capacidade de produção de biofilme representa maior risco à saúde dos pacientes acometidos por infecções causadas por estes agentes.(AU)


Justificación y objetivos: la sangre circulante es estéril y la presencia de microorganismos puede ser de interés clínico, especialmente en el entorno hospitalario, ya que puede causar procesos infecciosos y aumentar sustancialmente la morbilidad y la mortalidad. El objetivo de este trabajo fue caracterizar los aislamientos del género Staphylococcus spp. de infecciones del torrente sanguíneo en cuanto a la producción de biopelículas bacterianas y la resistencia a los principales antimicrobianos utilizados en la práctica clínica. Métodos: Se recogieron hemocultivos con una indicación de positividad para el crecimiento bacteriano de múltiples sectores del hospital de estudio, que posteriormente se procesaron para identificar el género bacteriano mediante el uso de pruebas fenotípicas para bacterias Gram positivas. La verificación del perfil de resistencia se realizó siguiendo la metodología de difusión de disco de Kirby-Bauer. La identificación de la producción y cuantificación de la biopelícula bacteriana se produjo siguiendo el protocolo descrito por O'toole (2010). Resultados: El aislado clínico más frecuente fue Staphylococcus coagulasa negativo 38 (54.29%), seguido de Staphylococcus aureus 32 (45.71%). Se observó resistencia a la eritromicina, norfloxacina, levofloxacina y azitromicina en la mayoría de los aislamientos (70%). Con respecto a la meticilina, se aislaron más MRSA (59,38%) que MR-CONS (47,37%). La UCI fue el lugar donde la formación de la biopelícula mostró datos indicativos de una mayor adherencia, que se asoció con las cepas de MRSA. Conclusión: los aislamientos bacterianos asociados con infecciones del torrente sanguíneo mostraron una alta resistencia a los antimicrobianos. La presencia de MRSA y MR-CONS con una capacidad de producción de biopelículas fuerte y / o moderada representa un mayor riesgo para la salud de los pacientes afectados por infecciones causadas por estos agentes.(AU)


Subject(s)
Staphylococcus , Drug Resistance, Microbial , Biofilms , Blood Culture , Anti-Infective Agents , Cross Infection
10.
Rev. cuba. estomatol ; 58(2): e3026, 2021. graf
Article in Portuguese | LILACS, CUMED | ID: biblio-1289394

ABSTRACT

Introdução: Os fitoconstituintes são moléculas naturais que apresentam atividade antimicrobiana satisfatória e devem ser estudados quanto ao seu uso como novas substâncias para irrigação dos canais radiculares. Objetivo: Avaliar o efeito inibitório dos fitoconstituintes cinamaldeído e α-terpineol frente a biofilmes monoespécie e duoespécie de microrganismos envolvidos na infecção endodôntica. Métodos: Trata-se de um estudo experimental na área de microbiologia aplicada, in vitro, cego quanto às análises e randomizado. Foram selecionados os fitoconstituintes cinamaldeído e α-terpineol. A atividade antimicrobiana frente Candida albicans e Enterococcus faecalis foi avaliada por meio da análise da capacidade metabólica com o uso da resazurina e análise da viabilidade celular pelo plaqueamento. O meio de cultura e a clorexidina 1 porcento serviram de controle negativo e positivo, respectivamente. Resultados: Observou-se ausência de crescimento para exposição dos biofilmes nas concentrações de 10 e 5 mg/mL de ambos os fitoconstituintes. Na concentração de 2,5 mg/mL de terpineol, constatou-se crescimento somente nos biofilmes monoespécie de C. albicans e duoespécie. Já na concentração de 1mg/mL de terpineol e cinamaldeído, verificou-se crescimento para todos os biofilmes. Conclusão: O cinamaldeído e α-terpineol apresentaram atividade inibitória frente biofilmes monoespécie e duoespécie de Candida albicans e Enterococcus faecalis, nas concentrações de 10 e 5 mg/mL(AU)


Introducción: Los fitoconstituyentes son moléculas naturales que presentan actividad antimicrobiana satisfactoria y deben ser estudiados en cuanto a su uso como nuevas sustancias para irrigación de los canales radiculares. Objetivo: Evaluar el efecto inhibitorio de fitoconstituyentes cinamaldehído y α-terpineol frente a biopelículas monoespecies y duoespecies de microorganismos involucrados en la infección endodóntica. Métodos: Estudio experimental en el campo de la microbiología aplicada, in vitro, ciego al análisis y aleatorizado. Se seleccionaron los fitoconstituyentes cinamaldehído y α-terpineol. La actividad antimicrobiana frente Candida albicans y Enterococcus faecalis fue evaluada por medio del análisis de la capacidad metabólica con el uso de la resazurina y análisis de la viabilidad celular por el plaqueamiento. El medio de cultivo y la clorexidina 1 por ciento sirvieron de control negativo y positivo, respectivamente. Resultados: Se observó ausencia de crecimiento para exposición de las biopelículas en las concentraciones de 10 y 5 mg/mL de ambos fitoconstituyentes. En la concentración de 2,5 mg/mL de terpineol se constató crecimiento solo en los biofilmios monoespecies de C. albicans y duoespecies. En la concentración de 1 mg/mL de terpineol y cinamaldehído se verificó crecimiento para todas las biopelículas. Conclusiones: Cinamaldehído y α-terpineol presentaron actividad inhibitoria frente a biofilmes monoespecies y duoespecies de Candida albicans y Enterococcus faecalis, en las concentraciones de 10 y 5 mg/mL(AU)


Introduction: Phytoconstituents are natural molecules displaying satisfactory antimicrobial activity. Studies should be conducted about their use as new root canal irrigants. Objective: Evaluate the inhibitory effect of the phytoconstituents cinnamaldehyde and α-terpineol against mono- and duo-species biofilms of microorganisms involved in endodontic infection. Methods: An experimental applied microbiology blind randomized in vitro study was conducted. The phytoconstituents selected were cinnamaldehyde and α-terpineol. Antimicrobial activity against Candida albicans and Enterococcus faecalis was evaluated by metabolic capacity analysis with resazurin and cell viability analysis by the plaque. The culture medium and 1 percent chlorhexidine served as negative and positive controls, respectively. Results: An absence of growth was observed for exposure of the biofilms at concentrations of 10 and 5 mg/ml of both phytoconstituents. At a concentration of 2.5 mg/ml terpineol displayed growth only in the mono-species biofilms of C. albicans and duo-species biofilms. At a concentration of 1 mg/ml terpineol and cinnamaldehyde displayed growth in all biofilms. Conclusions: Cinnamaldehyde and α-terpineol displayed inhibitory activity against mono- and duo-species biofilms of Candida albicans and Enterococcus faecalis at concentrations of 10 and 5 mg/ml(AU)


Subject(s)
Humans , Biological Products/adverse effects , Candida albicans , Cell Survival , Biofilms , Enterococcus faecalis , Anti-Infective Agents/adverse effects
11.
Rev. Ciênc. Plur ; 7(2): 272-286, maio 2021. ilus, tab
Article in Portuguese | LILACS, BBO | ID: biblio-1284577

ABSTRACT

Introdução:A terapia de bochecho com óleos vegetais é uma cultura tradicional na Índia com intuito de prevenir afecções bucais, como cárie e doença periodontal. Atualmente, com as mudanças nos padrões alimentares da sociedade, tem-se empregado com maior valor o uso de óleos naturais, já que estudos demonstram sua importância para saúde.Objetivo:Esta revisão integrativa teve como objetivo selecionar evidências que mostrassem a utilização de óleos vegetais, com ação antimicrobiana, no controle do biofilme dental. Metodologia:O levantamento bibliográfico foi realizado nos meses de julho e agosto de 2020, por meio de pesquisa por via eletrônica, consultando-se o banco de dados Pubmed e SciELO (Scientific Electronic Library Online). Foram utilizados os descritores: Óleos vegetais, agentes antimicrobianos, Placa dental, Odontologia preventiva e Odontologia, os descritores foram usados separadamente e em cruzamento com o operador boleano AND. Utilizou-se os seguintes critérios de inclusão: Estudos clínicos, artigos completos e disponíveis gratuitamente, publicados no período de 2010 a 2020 em português e/ou inglês, e indexados nas bases de dados já citadas. Foram excluídos os trabalhos de conclusão de curso, dissertações, teses, livros e capítulos de livros, além de artigos duplicados e que não abordaram o tema do estudo.Resultados:Atenderam os critérios da pesquisa 04 estudos do tipo clínico randomizado, os quais mostraram eficiência dos óleos vegetais utilizados no controle do biofilme dental. A realização de pesquisas envolvendo e motivando a industrialização de produtos naturaiscontribui para a Política Nacional de Práticas Integrativas e Complementares.Conclusões:Os artigos analisados mostraram eficácia na utilização de óleos vegetais no controle do biofilme dental, sendo esses aplicados clinicamente,não mostrando prejuízo aos participantes e indicados como coadjuvante na manutenção da saúde bucal (AU).


Introduction:Mouthwash therapy with vegetable oils is a traditional culture in India with the aim of preventing oral diseases, such as caries and periodontal disease. Currently, with the changes in the dietary patterns of society, the use of natural oils has been used with greater value, since studies demonstrate its importance for health.Objective:This integrative review aimed to select evidence that showed the use of vegetable oils, with antimicrobial action, in the control of dental biofilm. Methodology:Thebibliographic survey was carried out in July and August 2020, through electronic research, consulting the Pubmed and SciELO database (Scientific Electronic Library Online). The descriptors were used: Vegetable oils, antimicrobial agents, dental plaque, preventive dentistry and dentistry, the descriptors were used separately and in cross-section with the Boolean operator AND. The following inclusion criteria were used: Clinical studies, complete and freely available articles, published between 2010 and 2020in Portuguese and / or English, and indexed in the databases already cited. Course completion papers, dissertations, theses, books and book chapters were excluded, as well as duplicate articles that did not address the subject of the study. Results:Four studies of randomized clinical type met the research criteria, which showed efficiency of vegetable oils used in the control of dental biofilm. Conducting research involving and motivating the industrialization of natural products contributes to the National Policy on Integrative and Complementary Practices.Conclusions:The analyzed articles showed efficacy in the use of vegetable oils in the control of dental biofilm, which were applied clinically without showing any harm to the participants and indicatedas an adjunct in maintaining oral health (AU).


Introducción: La terapia de enjuague bucal con aceites vegetales es una cultura tradicional en India con el objetivo de prevenir enfermedades bucales, como caries y enfermedad periodontal. Actualmente, con los cambios en los patrones dietéticos de la sociedad, se ha utilizado con mayor valor el uso de aceites naturales, ya que los estudios demuestran su importancia para la salud. Objetivo: Esta revisión integradora tuvo como objetivo seleccionar evidencias que mostraran el uso de aceites vegetales, con acción antimicrobiana, en el control del biofilm dental.Metodología: El relevamiento bibliográfico se realizó en julio y agosto de 2020, mediante investigación electrónica, consultando la base de datos Pubmed y SciELO (Scientific Electronic Library Online). Se utilizaron los descriptores: Aceites vegetales, agentes antimicrobianos, placa dental, odontología preventiva y odontología, los descriptores se utilizaron por separado y en corte transversal con el operador booleano AND. Se utilizaron los siguientes criterios de inclusión: Estudios clínicos, artículos completos y de libre acceso, publicados entre 2010 y 2020 en portugués y / o inglés, e indexados en las bases de datos ya citadas. Se excluyeron trabajos de finalización de curso, disertaciones, tesis, libros y capítulosde libros, así como artículos duplicados que no abordaran el tema de estudio. Resultados: Cuatro estudios de tipo clínico aleatorizado cumplieron con los criterios de investigación, los cuales mostraron la eficiencia de los aceites vegetales utilizados enel control del biofilm dental. Realizar investigaciones que involucren y motiven la industrialización de productos naturales contribuye a la Política Nacional de Prácticas Integrativas y Complementarias.Conclusiones: Los artículos analizados mostraron eficacia en el uso de aceites vegetales en el control del biofilm dental, los cuales fueron aplicados clínicamente sin mostrar daño a los participantes e indicados como coadyuvante en el mantenimiento de la salud bucal (AU).


Subject(s)
Plant Oils , Oral Health , Dental Plaque/pathology , Anti-Infective Agents/immunology , Mouthwashes/therapeutic use , Brazil/epidemiology , Surveys and Questionnaires , Biofilms
13.
Arq. bras. med. vet. zootec. (Online) ; 73(2): 343-351, Mar.-Apr. 2021. tab
Article in English | LILACS, VETINDEX | ID: biblio-1248926

ABSTRACT

The emergence of livestock-associated methicillin-resistant Staphylococcus aureus strains (LA-MRSA) and the potential role of pigs in the evolution of these strains has led to increased interest in research of these microorganisms. However, this has contributed to a lack of research in the isolation and characterization of methicillin-susceptible S. aureus strains (MSSA). In this study, the prevalence of S. aureus in pigs in the nursery and finishing stages were analyzed. The susceptibility profiles to antibiotics, tolerance to heavy metals, and biofilm production of the isolates were evaluated using phenotypic and genotypic techniques. A total of 1,250 colonies suggestive of Staphylococcus spp. were isolated from 128 pigs, of which 63.6% (n = 795) belonged to this microbial genus. Sixty-seven colonies isolated from 34 animals (26.5%) were confirmed as S. aureus (8.4%). No strains resistant to copper, zinc, or methicillin were detected; however, all strains presented a resistance profile to at least three different classes of antimicrobials and 21 produced biofilms. These data are of concern, as they indicate the need for increased surveillance in the use of antimicrobials as well as reinforce the importance of studies on MSSA strains.(AU)


A emergência de cepas de Staphylococcus aureus resistentes à meticilina associadas à pecuária (LA-MRSA) e o papel potencial dos suínos na evolução dessas cepas têm levado ao aumento do interesse na pesquisa desses microrganismos. No entanto, isso tem contribuído para a falta de estudos sobre o isolamento e a caracterização de cepas de S. aureus sensíveis à meticilina (MSSA). Neste estudo, foi analisada a prevalência de S. aureus em suínos nas fases de creche e terminação. Os perfis de suscetibilidade aos antibióticos, a tolerância a metais pesados e a produção de biofilme dos isolados foram avaliados por meio de técnicas fenotípicas e genotípicas. Um total de 1.250 colônias sugestivas de Staphylococcus spp. foi isolado de 128 suínos, das quais 63,6% (n = 795) pertenciam a esse gênero microbiano. Sessenta e sete colônias isoladas de 34 animais (26,5%) foram confirmadas como S. aureus (8,4%). Nenhuma cepa resistente ao cobre, ao zinco ou à meticilina foi detectada; entretanto, todas as cepas apresentaram perfil de resistência a pelo menos três classes diferentes de antimicrobianos e 21 produziam biofilme. Esses dados são preocupantes, pois indicam a necessidade de maior vigilância no uso de antimicrobianos, bem como reforçam a importância de estudos com cepas de MSSA.(AU)


Subject(s)
Animals , Staphylococcus aureus/isolation & purification , Swine , Virulence Factors/analysis , Methicillin-Resistant Staphylococcus aureus , Drug Resistance, Microbial , Biofilms
14.
Braz. j. biol ; 81(1): 11-17, Feb. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153310

ABSTRACT

Abstract Xanthomonas oryzae pv. oryzae (Xoo), a pathogen responsible for rice bacterial leaf blight, produces biofilm to protect viable Xoo cells from antimicrobial agents. A study was conducted to determine the potency of Acacia mangium methanol (AMMH) leaf extract as a Xoo biofilm inhibitor. Four concentrations (3.13, 6.25, 9.38, and 12.5 mg/mL) of AMMH leaf extract were tested for their ability to inhibit Xoo biofilm formation on a 96-well microtiter plate. The results showed that the negative controls had the highest O.D. values from other treatments, indicating the intense formation of biofilm. This was followed by the positive control (Streptomycin sulfate, 0.2 mg/mL) and AMMH leaf extract at concentration 3.13 mg/mL, which showed no significant differences in their O.D. values (1.96 and 1.57, respectively). All other treatments at concentrations of 6.25, 9.38, and 12.5 mg/mL showed no significant differences in their O.D. values (0.91, 0.79, and 0.53, respectively). For inhibition percentages, treatment with concentration 12.5 mg/mL gave the highest result (81.25%) followed by treatment at concentrations 6.25 and 9.38 mg/mL that showed no significant differences in their inhibition percentage (67.75% and 72.23%, respectively). Concentration 3.13 mg/mL resulted in 44.49% of biofilm inhibition and the positive control resulted in 30.75% of biofilm inhibition. Confocal laser scanning microscopy (CLSM) analysis of Xoo biofilm inhibition and breakdown showed the presence of non-viable Xoo cells and changes in aggregation size due to increase in AMMH leaf extract concentration. Control slides showed the absence of Xoo dead cells.


Resumo Xanthomonas oryzae pv. oryzae (Xoo), um patogênico responsável pela influência bacteriana na folha do arroz, produz biofilme para proteger células Xoo viáveis de agentes antimicrobianos. Foi conduzido um estudo para determinar a potência do extrato de folha de Acacia mangium methanol (AMMH) como um inibidor de biofilme Xoo. Quatro concentrações (3,13, 6,25, 9,38 e 12,5 mg/mL) de extrato de folha de AMMH foram testadas quanto à sua capacidade de inibir a formação de biofilme Xoo em uma placa de microtitulação de 96 poços. Os resultados mostraram que os controles negativos tiveram o maior valor de OD do que os outros tratamentos, indicando a intensa formação de biofilme. Isso foi seguido do controle positivo (sulfato de estreptomicina, com concentração de 0,2 mg/mL, e extrato de folha de AMMH, com concentração de 3,13 mg/mL), que não apresentou diferenças significativas nos seus valores OD (1,96 e 1,57, respectivamente). Todos os outros tratamentos com concentrações de 6,25, 9,38, e 12,5 mg/mL não tiveram diferenças significativas nos seus valores OD (0,91, 0,79, e 0,53, respectivamente). Para percentagens de inibição, o tratamento com concentração 12,5 mg/mL apresentou o maior resultado (81,25%), seguido do tratamento em concentrações de 6,25 e 9,38 mg/mL, que não mostraram diferenças significativas na sua percentagem de inibição (67,75 e 72,23%, respectivamente). Concentração 3,13 mg/mL resultou em 44,49% de inibição do biofilme, e o controle positivo resultou em 30,75% de inibição do biofilme. Análise por microscopia confocal de leitura a laser de inibição e separação de biofilme Xoo revelou a presença de células Xoo não viáveis e alterações no tamanho da agregação por causa do aumento na concentração de extrato de folha de AMMH. Slides de controle mostraram a ausência de células Xoo mortas.


Subject(s)
Oryza , Acacia , Plant Diseases , Xanthomonas , Plant Extracts/pharmacology , Biofilms , Methanol
15.
J. appl. oral sci ; 29: e20200733, 2021. graf
Article in English | LILACS | ID: biblio-1154616

ABSTRACT

Abstract Enterococcus faecalis (E. faecalis), one of the main pathogens responsible for refractory periapical periodontitis and nosocomial infections, exhibits markedly higher pathogenicity in biofilms. Objectives Studies have shown that caseinolytic protease P (ClpP) is involved in biofilm formation. However, to date, few studies have investigated the role of ClpP in the survival of E. faecalis, and in enhancing biofilm formation. Therefore, we investigated the role of ClpP in the formation of E. faecalis biofilms. Methodology In our study, we used homologous recombination to construct clpP deleted and clpP complement strains of E. faecalis ATCC 29212. A viable colony counting method was used to analyze the growth patterns of E. faecalis. Crystal violet staining (CV) and confocal scanning laser microscopy (CLSM) were used to characterize biofilm mass formation and scanning electron microscopy (SEM) was used to observe the biofilm microstructure. Data was statistically analyzed via Student's t-test or one-way analysis of variance (ANOVA). Results The results exhibited altered growth patterns for the clpP deletion strains and depleted polysaccharide matrix, resulting in reduced biofilm formation capacity compared to the standard strains. Moreover, ClpP was observed to increase biofilm formation in E. faecalis. Conclusion Our study shows that ClpP can increase biofilm formation in E. faecalis and emphasizes the importance of ClpP as a potential target against E. faecalis.


Subject(s)
Humans , Enterococcus faecalis , Biofilms , Peptide Hydrolases , Virulence , Microscopy, Electron, Scanning , Microscopy, Confocal , Endopeptidase Clp
16.
J. appl. oral sci ; 29: e20200778, 2021. tab, graf
Article in English | LILACS | ID: biblio-1340096

ABSTRACT

Abstract Objective this study evaluated the mineral and microbiological response of biofilms originating from different types of saliva inoculum with distinct levels of caries activity. Methodology the biofilms grown over enamel specimens originated from saliva collected from a single donor or five donors with two distinct levels of caries activity (caries-active and caries-free) or from pooling saliva from ten donors (five caries-active and five caries-free). The percentage surface hardness change (%SHC) and microbiological counts served as outcome variables. Results the caries activity of donors did not affect the %SHC values. Inoculum from five donors compared to a single donor showed higher %SHC values (p=0.019). Higher lactobacilli counts were observed when saliva from caries-active donors was used as the inoculum (p=0.017). Pooled saliva from both caries activity levels showed higher mutans streptococci counts (p<0.017). Conclusion Overall, pooled saliva increased the mineral response of the derived biofilms, but all the inoculum conditions formed cariogenic biofilms and caries lesions independently of caries activity.


Subject(s)
Humans , Saliva , Dental Caries , Streptococcus mutans , Biofilms , Dental Caries Susceptibility , Minerals
17.
J. appl. oral sci ; 29: e20201031, 2021. tab, graf
Article in English | LILACS | ID: biblio-1250189

ABSTRACT

Abstract Fixed orthodontic appliances may lead to biofilm accumulation around them that may increase caries risk. This study aimed to evaluate the influence of quaternary ammonium methacrylates (QAMs) on the physicochemical properties, cytotoxicity, and antibacterial activity of adhesive resins for orthodontic purposes. Methodology: A base resin was prepared with a comonomer blend and photoinitiator/co-initiator system. Two different QAMs were added to the base adhesive: dimethylaminododecyl methacrylate at 5 wt.% (DMADDM) or dimethylaminohexadecyl methacrylate (DMAHDM) at 10 wt.%. The base adhesive, without QAMs, (GC) and the commercial Transbond™ XT Primer 3M (GT) were used as control. The resins were tested immediately and after six months of aging in the water regarding the antibacterial activity and shear bond strength (SBS). The antibacterial activity was tested against Streptococcus mutans via metabolic activity assay (MTT test). The groups were also tested for the degree of conversion (DC) and cytotoxicity against keratinocytes. Results: The resins containing QAM showed antibacterial activity compared to the commercial material by immediately reducing the metabolic activity by about 60%. However, the antibacterial activity decreased after aging (p<0.05). None of the groups presented any differences for SBS (p>0.05) and DC (p>0.05). The incorporation of DMADDM and DMAHDM significantly reduced the keratinocyte viability compared to the GT and GC groups (p<0.05). Conclusion: Both adhesives with QAMs showed a significant reduction in bacterial metabolic activity, but this effect decreased after water aging. Lower cell viability was observed for the group with the longer alkyl chain-QAM, without significant differences for the bonding ability and degree of conversion. The addition of QAMs in adhesives may affect the keratinocytes viability, and the aging effects maybe decrease the bacterial activity of QAM-doped materials.


Subject(s)
Orthodontic Brackets , Streptococcus mutans , Materials Testing , Biofilms , Resin Cements , Dental Cements , Methacrylates , Anti-Bacterial Agents
18.
J. appl. oral sci ; 29: e20210024, 2021. tab, graf
Article in English | LILACS | ID: biblio-1340097

ABSTRACT

Abstract Understanding the behavior of Candida spp. when exposed to denture disinfectants is essential to optimize their effectiveness. Changes in the virulence factors may cause increased resistance of Candida spp. to disinfectant agents. Objective To evaluate the microbial load, cellular metabolism, hydrolytic enzyme production, hyphae formation, live cell and biofilm quantification of Candida albicans, Candida tropicalis and Candida glabrata after exposure to disinfectant solutions. Methodology Simple biofilms were grown on heat-polymerized acrylic resin specimens, and divided into groups according to solutions/strains: distilled water (control); 0.25% sodium hypochlorite (NaOCl 0.25% ); 10% Ricinus communis (RC 10%); and 0.5% Chloramine T (CT 0.5%). The virulence factors were evaluated using the CFU count (microbial load), XTT method (cell metabolism), epifluorescence microscopy (biofilm removal and live or dead cells adhered), protease and phospholipase production and hyphae formation. Data were analyzed (α=0.05) by one-way ANOVA/ Tukey post hoc test, Kruskal-Wallis test and Wilcoxon test. Results NaOCl 0.25% was the most effective solution. CT 0.5% reduced the number of CFUs more than RC 10% and the control. RC 10% was effective only against C. glabrata. RC 10% and CT 0.5% decreased the cellular metabolism of C. albicans and C. glabrata. Enzyme production was not affected. Hyphal growth in the RC 10% and CT 0.5% groups was similar to that of the control. CT 0.5% was better than RC 10% against C. albicans and C. tropicalis when measuring the total amount of biofilm and number of living cells. For C. glabrata, CT 0.5% was equal to RC 10% in the maintenance of living cells; RC 10% was superior for biofilm removal. Conclusions The CT 0.5% achieved better results than those of Ricinus communis at 10%, favoring the creation of specific products for dentures. Adjustments in the formulations of RC 10% are necessary due to efficacy against C. glabrata. The NaOCl 0.25% is the most effective and could be suitable for use as a positive control.


Subject(s)
Candida , Disinfectants , Acrylic Resins , Candida albicans , Biofilms , Virulence Factors
19.
J. appl. oral sci ; 29: e20200948, 2021. tab, graf
Article in English | LILACS | ID: biblio-1340105

ABSTRACT

Abstract Appropriated denture hygiene is a predictive factor for longevity of rehabilitation treatment and maintenance of the oral mucosal health. Although, disinfectant solutions are commonly used as denture cleansers, the impact of these solutions on acrylic resin-based dentures remain unclear. Objective To evaluate, in vitro, the antibiofilm activity of complete denture hygiene solutions and their effects on physical and mechanical properties of acrylic resin. Methodology For antibiofilm activity measurement acrylic resin specimens were contaminated with Candida albicans, Candida glabrata and Streptococcus mutans. After biofilm growth, the specimens were assigned to the hygiene solutions: Distilled water (Control); 0.2% Sodium hypochlorite (SH); Efferdent Power Clean Crystals (EPC) and 6.25% Ricinus communis (RC). The viability of microorganisms was evaluated by agar plate counts. In parallel, physical, and mechanical properties of the acrylic resin were evaluated after simulating a 5-year period of daily immersion in the previously mentioned solutions. The changes in surface roughness, color, microhardness, flexural strength, impact strength, sorption and solubility were evaluated. Data were compared by ANOVA followed by the Tukey test or Kruskal-Wallis followed by the Dunn test depending on the distribution (α=0.05). Results Regarding antibiofilm action, SH eliminated all microorganisms while EPC and RC exhibited moderate action against S. mutans (p=0.001) and C. glabrata (p<0.001), respectively. Relative to effects on the physical and mechanical properties of the acrylic resin, RC led to higher values of color change (p=0.030), hardness (p<0.001), surface roughness (p=0.006) and flexural strength (p<0.001). Moreover, RC induced the highest values of changes in solubility (p<0.001). EPC promoted greater changes in surface morphology, whereas immersion in SH retained the initial appearance of the acrylic resin surface. All hygiene solutions reduced the impact strength (p<0.05). Conclusion SH presented the most effective antibiofilm activity. In addition, changes on properties were observed after immersion in RC, which were considered within acceptable limits.


Subject(s)
Acrylic Resins , Denture Cleansers/pharmacology , Surface Properties , Materials Testing , Hygiene , Biofilms , Denture Bases , Denture, Complete
20.
J. appl. oral sci ; 29: e20200865, 2021. graf
Article in English | LILACS | ID: biblio-1286916

ABSTRACT

Abstract Denture stomatitis is the most frequent oral lesion in removable prosthesis wearers, with high recurrence rates and a complex treatment. Objective This study describes a protocol to obtain and to contaminate a palatal device with Candida albicans biofilm that could be used for an animal model of denture stomatitis. Methodology Acrylic resin devices (N=41) were obtained from impressions of the palates of Wistar rats with individual trays and polyether. The efficacy of microwave irradiation (MW), ultraviolet light (UV), or ultrasonic bath (US) was assessed by colony viability and spectrophotometric analyses (n=5) in order to select the most appropriate method for sterilizing the devices. Then, different devices (n=5) were contaminated with C. albicans and evaluated by CFU/mL determination, scanning electron microscopy, and laser confocal microscopy. Device stabilization was assessed with either autopolymerizing acrylic resins or a self-adhesive resin cement (n=2). The spectrophotometric data were analyzed by one-way ANOVA followed by the Tukey's HSD post-hoc test (α=0.05). Results MW was the only method capable of sterilizing the devices, and the contamination protocol developed a mature and viable C. albicans biofilm (~1.2 x 106 CFU/mL). The self-adhesive resin cement was the best stabilization material. Conclusions This acrylic resin palatal device was designed to be similar to the clinical situation of contaminated prostheses, with easy manufacturing and handling, effective stabilization, and satisfactory contamination. Thus, the acrylic device can be a valuable tool in the development of denture stomatitis in rats.


Subject(s)
Animals , Rats , Stomatitis, Denture , Candida albicans , Palate , Acrylic Resins , Rats, Wistar , Biofilms , Denture Bases
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