Las biopelículas y su interrelación con la patología crónica del oído medio / Biofilms and their relationship with chronic middle ear pathology

El concepto de biopelículas ha surgido de forma paulatina durante un largo período; se presentan como estructuras tridimensionales compuestas por células sésiles de microorganismos que crecen y se adhieren irreversiblemente a superficies, tanto vivas como inertes. Su capacidad de desarrollarse, tanto en superficies bióticas como abióticas, es una característica que los relaciona directamente con la salud humana. Distintas infecciones óticas se han inculpado a la presencia de biopelículas en las mucosas como en la otitis media con efusión, de igual forma se manifiestan en la aparición y persistencia de la otitis media crónica. Las biopelículas afines con otitis media, generalmente, contienen uno o múltiples especies de bacterias otopatógenas primarias. La comprensión de la biopelicula auxiliará el progreso de nuevas terapias y estrategias de control, al evitar enfermedades infecciosas ya que las bacterias formadoras de biopelículas son una seria amenaza para la salud pública debido a su alta resistencia a los antimicrobianos.

The concept of biofilms has emerged gradually over a long period; they appear as three-dimensional structures composed of sessile cells of microorganisms that grow and adhere irreversibly to surfaces, both living and inert. Their ability to develop, both on biotic and abiotic surfaces, is a characteristic that directly relates them to human health. Different ear infections have been blamed on the presence of biofilms on the mucous membranes, such as otitis media with effusion, in the same way they manifest themselves in the appearance and persistence of chronic otitis media. Otitis media-related biofilms generally contain one or multiple species of primary otopathogenic bacteria. The understanding of the biofilm will help us refine new therapies and control strategies, by avoiding infectious diseases since biofilm-forming bacteria are a serious threat to public health due to their high resistance to antimicrobials.

Influencia de la higiene bucal en el estado de salud de los tejidos periimplantarios / Influence of oral hygiene on peri-implant tissue health status

Introducción: el estado de salud de los tejidos periimplantarios es de vital importancia en el éxito de la rehabilitación implantosoportada, por esta razón, es necesario observar todos aquellos factores que contribuyen a mantener este estado y dentro de ellos, principalmente: la higiene bucal. Objetivo: determinar la influencia de la higiene bucal en el estado de salud de los tejidos periimplantarios. Métodos: se realizó un estudio descriptivo, observacional y transversal en el servicio de Prótesis de la Facultad de Estomatología de Villa Clara, en el período comprendido entre los años 2017 y 2019. El universo de estudio estuvo constituido por 45 pacientes portadores de rehabilitaciones implantosoportadas; las unidades de análisis fueron los implantes y los tejidos que rodean a las 85 prótesis fijas realizadas a dichos pacientes que cumplieron con los criterios de inclusión. Se emplearon la observación clínica y radiográfica, y se elaboró un formulario como instrumento. Se evaluó la higiene bucal y el estado de los tejidos periimplantarios como principales variables. La información obtenida se recopiló en una base de datos, se procesó y se sometió a pruebas de independencia (el estadígrafo Ji cuadrado y su posibilidad asociada) para mostrar la relación entre las variables. Resultados: las variables analizadas evidenciaron una relación significativa de la higiene bucal con el estado de salud de los tejidos periimplantarios a favor de la buena higiene y los tejidos sanos. Conclusiones: la buena higiene bucal evidenciada contribuyó a que los tejidos periimplantarios se mantuvieran sanos.

Introduction: peri-implant tissue health state is of vital importance in the success of implant-supported rehabilitation; for this reason, it is necessary to observe all those factors that contribute to maintaining this state, mainly oral hygiene. Objective: to determine the influence of oral hygiene on peri-implant tissue health status. Methods: a descriptive, observational and cross-sectional study was carried out in the Prosthesis service at the Dental Faculty of Villa Clara between 2017 and 2019. The universe of study consisted of 45 patients with implant-supported rehabilitations; the units of analysis were the implants and the tissues surrounding the 85 fixed prostheses performed on those patients who met the inclusion criteria. Clinical and radiographic observations were used, and a form was developed as an instrument. Oral hygiene and peri-implant tissue state were evaluated as the main variables. The information obtained was compiled in a database as well as processed and subjected to independence tests (the Chi-square statistic and its associated possibility) to show the relationship among the variables. Results: the analyzed variables showed a significant relationship between oral hygiene and the peri-implant tissue health status in favour of good hygiene and healthy tissues. Conclusions: the evidenced good oral hygiene contributed to the maintenance of healthy peri-implant tissues.

Evaluación de la formación de biopelículas en aislamientos bacterianos y fúngicos por el método semicuantitativo de microtitulación con cristal violeta y el cualitativo de agar con rojo Congo / Assessment of biofilms formation of bacterial and fungal isolates using qualitative Congo red agar and semiquantitative crystal violet microtiter methods

Introducción. El 65 % de las infecciones humanas son producidas por bacterias o levaduras, cuya capacidad de formar biopelículas las hace más resistentes a los antimicrobianos y antifúngicos. Objetivo. Determinar la capacidad de formación de biopelículas en aislamientos bacterianos y fúngicos por medio de los métodos cuantitativo de microtitulación con cristal violeta y cualitativo de cultivo en agar con rojo Congo. Materiales y métodos. Con el método cuantitativo, se utilizaron los medios de cultivo infusión cerebro-corazón, tripticasa de soya y Müeller-Hinton para aislamientos bacterianos; para levaduras, se usaron caldo infusión cerebro-corazón y Sabouraud dextrosa. Para el método cualitativo de cultivo en agar, se utilizaron los mismos medios de cultivo más una solución con 3 % de rojo Congo y 10 % de dextrosa. Cómo método de referencia, se utilizó la propuesta de Stepanovic et al. Resultados. Se evaluaron 103 aislamientos bacterianos y 108 de levaduras. No es recomendable sustituir el caldo infusión cerebro-corazón por los caldos tripticasa de soya y Müeller-Hinton en el método cuantitativo, para evaluar la formación de biopelículas en los aislamientos bacterianos. El medio Sabouraud dextrosa, en caldo y agar, puede sustituir al de infusión de cerebro-corazón para evaluar la formación de biopelículas en levaduras, tanto por el método cuantitativo como por el cualitativo. Conclusión. El estudio de las biopelículas en el laboratorio de microbiología, a partir del método cualitativo de cultivo en agar con rojo Congo, es un procedimiento sencillo, rápido y de bajo costo, que proporciona información útil para el diagnóstico y la terapéutica de infecciones persistentes causadas por bacterias y levaduras.

Introduction. Sixty-five percent of human infections are caused by bacteria or yeasts able to form biofilms. This feature makes them more resistant to antimicrobials and antifungals. Objective. To determine biofilm formation capacity of bacterial and fungal isolates by quantitative crystal violet microtiter and qualitative Congo red agar methods. Materials and methods. Brain-heart infusion, trypticase soy broth and Müeller-Hinton culture media were used in bacterial isolates for the quantitative method; brain-heart infusion broth and Sabouraud dextrose were used for yeasts. The same culture media plus 3% Congo red and 10% dextrose were used to apply the qualitative method in agar. The proposal by Stepanovic, et al. was used as a reference method. Results. We evaluated 103 bacterial isolates and 108 yeasts isolates. We did not recommend substitute brain-heart infusion broth for trypticase soy and Müeller-Hinton broths for biofilm formation assessment in bacterial isolates using the quantitative method. Sabouraud dextrose medium, both broth and agar, can replace brain-heart infusion to assess biofilm formation in yeasts, quantitatively and qualitatively. Conclusion. The study of biofilms in the microbiology laboratory, using Congo red agar qualitative method, is a simple, fast, and inexpensive procedure that provides precise information for the diagnosis and treatment of persistent infections caused by bacteria and yeasts.

Polihexametilenobiguanida versus solução salina na carga microbiana em feridas: protocolo de revisão sistemática / Polyhexamethylene biguanide versus saline on microbial load in wounds: a systematic review protocol

OBJETIVO: Analisar a efetividade de Polihexametileno Biguanida (PHMB), comparado à solução salina na carga microbiana de pacientes com feridas. MÉTODO: Protocolo de revisão sistemática, construído segundo o Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA), de acordo com metodologia do Joanna Briggs Institute (JBI). Os estudos serão avaliados por dois pesquisadores independentes, nas bases de dados: Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Base de Dados de Enfermagem (BDENF), Sistema Online de Busca e Análise de Literatura Médica (MEDLINE)e Excerpta Medica Database (Embase). As pesquisas a serem incluídas serão aquelas publicadas em português, inglês ou espanhol e a busca não definirá recorte temporal. Serão desconsiderados estudos em animais ou in vitro, revisões, cartas ao editor ou estudos de casos. Após a seleção dos estudos, a extração de dados ocorrerá de maneira sistemática e os registros correspondentes serão feitos de forma narrativa e tabular.

OBJECTIVE: To analyze the effectiveness of polyhexamethylene biguanide (PHMB) compared to saline on the microbial load of wounds. METHOD: Systematic review protocol, built according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) and the Joanna Briggs Institute's (JBI) methodology. Studies will be evaluated by two independent researchers in the following databases: Latin America and the Caribbean Literature on Health Sciences (LILACS), Nursing Database (BDENF), Medical Literature Analysis and Retrieval System Online (MEDLINE), and Excerpta Medica Database (Embase). Studies published in Portuguese, English, or Spanish will be included, and the search will not be restricted by publication date. Animal or in vitro studies, reviews, letters to the editor, and case studies will be excluded. After selecting studies, data extraction will take place systematically, and the corresponding records will be presented in a narrative and tabular way.

Fibra de carbono ativada: avaliação das interações biológicas in vitro / Activated carbon fiber: evaluation of biological interactions in vitro

Devido a constante necessidade de desenvolver materiais biocompatíveis com propriedades osteocondutores e osteoindutoras, a presente tese conta com o desenvolvimento de dois estudos in vitro com fibra de carbono obtida a partir de fibra PAN têxtil, incorporada com diferentes íons de metais, na osteogênese com vistas à compreensão das necessidades da engenharia tecidual no desenvolvimento desse biomaterial com adequadas propriedades biológicas. As células foram obtidas dos fêmures de 09 ratos machos adultos (Wistar) pesando 300g, com 90 dias.Estudo 1: A partir da preparação da fibras foram obtidos corpos de prova de 4 mm de diâmetro e 2 mm de altura, dos seguintes grupos: fibra de carbono não ativada (FCNA), fibra carbono ativada (FCA) e fibra carbono ativada com prata (FCAAg). Após plaqueamento (n=5) em meio suplementado (MTS) e meio suplementado osteogênico (MTSO) foram analisados: viabilidade celular, conteúdo de proteína total (PT), atividade de fosfatase alcalina (ALP), interaçãocelular e formação de nódulos de mineralização. Foi avaliada a formação de biofilme nos corpos de prova, utilizando cepas de S. aureus, P. aeruginosa e E. coli. Na viabilidade celular, houve diferença estatística entre grupo controle celular (C) e FCA-MTS, FCAAg-MTS e FCAAg-MTSO. Em PT, não houvediferença, na ALP houve diferença entre C-MTS e as fibras, C-MTSO se mostrou semelhante. Em nódulos, houve diferença entre C-MTS e C-MTSO e as fibras do MTSO. Houve redução de formação de biofilme do S. aureus na FCAAg.Estudo 2: Foram obtidos corpos de prova da mesma dimensão do estudo 1 (n=5) dos seguintes grupos: fibra carbono ativada com prata (FCAAg), fibra carbono ativada com ouro (FCAAu), fibra carbono ativada com cobre (FCACu), fibra carbono ativada com paládio (FCAPd) e fibra carbono ativada com platina (FCAPt). Foram quantificadas a proliferação celular, viabilidade celular, formação de nódulos de mineralização, conteúdo de PT e ALP. Todas as amostras mostraram-se semelhantes quanto a proliferação celular, com exceção do grupo FCAAg comparado ao grupo controle (C). Sobre viabilidade celular, C obteve maior viabilidade que os outros grupos, e FCA obteve maior taxa que os grupos FCAAg, FCACu, FCAPt, sendo semelhante aos grupos FCAAu e FCAPd. Já os grupos FCAAu e FCAPd apresentaram diferença aos grupos FCAAg e FCACu. Na análise de expressão de PT apenas houve diferença entre FCA e FCAAu, sendo FCAAu com menor expressão de produção de PT. Na avaliação da ALP os grupos FCAAg e FACu mostraram diferença estatística e inferior com os grupos C, FCAAu, FCAPd e FCAPt, além disso, o grupo FCA mostrou menor taxa que C.Conclusões: As fibras utilizadas de base para a incorporação dos íons demonstraram grande potencial para uso como scaffold para reparação óssea, isso porque em ambos os estudos, na forma ativada e não ativada, as fibras apresentaram viabilidade celular e quantificação de cálcio satisfatórias. Sendo a versão não ativada mais econômica no que diz respeito ao tempo e custo de preparação. Mais estudos devem ser empregados a fim de assegurar sua segurança clínica em relação à citotoxicidade da incorporação de íons de ouro e paládio.(AU)

Due to the constant need to develop biocompatible materials with osteoconductive and osteoinductive properties, this thesis involves the development of two in vitro studies with carbon fiber obtained from textile PAN fiber, incorporated with different metal ions, in osteogenesis with a view to understanding the needs of tissue engineering in the development of this biomaterial with adequate biological properties. The cells were obtained from the femurs of 9 adult male rats (Wistar) weighing 300g, aged 90 days. Study 1: From the fiber preparation, specimens measuring 4 mm in diameter and 2 mm in height were obtained from the following groups: non-activated carbon fiber (FCNA), activated carbon fiber (FCA) and silver-activated carbon fiber (FCAAg). After plating (n=5) in supplemented medium (MTS) and supplemented osteogenic medium (MTSO), cell viability, total protein content (PT), alkaline phosphatase (ALP) activity, cell interaction and formation of mineralization nodules were analyzed. . Biofilm formation was evaluated in the specimens, using strains of S. aureus, P. aeruginosa and E. coli. In cell viability, there was a statistical difference between the cell control group (C) and FCAMTS, FCAAg-MTS and FCAAg-MTSO. In PT, there was no difference, in ALP there was a difference between C-MTS and fibers, C-MTSO was similar. In nodules, there was a difference between C-MTS and C-MTSO and MTSO fibers. There was a reduction in S. aureus biofilm formation on FCAAg. Study 2: Specimens of the same size as in study 1 (n=5) were obtained from the following groups: carbon fiber activated with silver (FCAAg), carbon fiber activated with gold (FCAAu), carbon fiber activated with copper (FCACu), palladium-activated carbon fiber (FCAPd) and platinum-activated carbon fiber (FCAPt). Cell proliferation, cell viability, formation of mineralization nodules, PT and ALP content were quantified. All samples were similar in terms of cell proliferation, with the exception of the FCAAg group compared to the control group (C). Regarding cell viability, C obtained higher viability than the other groups, and FCA obtained a higher rate than the FCAAg, FCACu, FCAPt groups, being similar to the FCAAu and FCAPd groups. The FCAAu and FCAPd groups showed differences to the FCAAg and FCACu groups. In the analysis of PT expression, there was only a difference between FCA and FCAAu, with FCAAu having lower expression of PT production. In the ALP assessment, the FCAAg and FACu groups showed a lower statistical difference compared to the C, FCAAu, FCAPd and FCAPt groups, in addition, the FCA group showed a lower rate than C. Conclusions: The fibers used as the basis for the incorporation of ions demonstrated great potential for use as a scaffold for bone repair, because in both studies, in activated and non-activated form, the fibers showed satisfactory cell viability and calcium quantification. The non-activated version is moreeconomical in terms of preparation time and cost. More studies must be carried out to ensure its clinical safety in relation to the cytotoxicity of the incorporation of gold and palladium ions. (AU)

Mango peel as a potential enzyme inducer in Trichoderma harzianum: a strategy for cariogenic biofilm degradation and reuse of industrial waste

Water-insoluble exopolysaccharides (I-EPS) are a virulence factor for dental biofilms. It has already been demonstrated that mango pulp induces the secretion of glucan-hydrolytic enzymes in the fungus Trichoderma harzianum, and that they have an effect on I-EPS from young biofilms. Aim: Evaluate the effect of mango peel as an enzyme inducer in T. harzianum, and the effect of enzymes secreted on mature biofilms. Methods: Fractions of the peel (PL) and ethanol-precipitated pulp (PP) of Tommy Atkins mangoes were sterilized and added to a culture medium containing T. harzianum for induction of hydrolytic enzymes. After 192 h, the culture medium was centrifuged and the supernatant (enzyme extract) was used as treatment on S. mutans biofilms (n=9): a) NaCl 0.9 %; b) 0.12 % chlorhexidine digluconate; and c) extract of enzymes induced by PL or PP. Acidogenicity, bacterial viability, quantification of insoluble polysaccharides, and three-dimensional analysis of the biofilm by scanning electron microscopy (SEM) was performed. Data were analyzed by ANOVA followed by the Tukey test (α=5 %). Results: The hydrolytic enzymes did not alter the metabolism or bacterial viability of the biofilm (p<0.05). Although the images obtained by SEM suggest some degree of matrix degradation, the quantification of I-EPS for the PL and PP groups did not differ from the control group (p>0.05), suggesting a slight effect on the disorganization of the mature S. mutans biofilm. Conclusion: The results suggest that mango peel fraction can induce secretion of mutanase by T. harzianum, however in an insufficient amount to generate significant degradation on cariogenic biofilm.

Establishment of a saliva donor selection for in vitro biofilm growth / Seleção de doadores de saliva para crescimento de biofilme in vitro

Introdução: O emprego de biofilmes polimicrobianos, utilizando a saliva como inóculo, é um modelo promissor para o estudo de biofilmes cariogênicos in vitro. Entretanto, ainda não existe uma padronização para seleção de doadores de saliva. Objetivo: O objetivo deste estudo foi estabelecer uma metodologia para seleção de doadores de saliva utilizando fatores salivares microbianos e características in vitro do biofilme. Material e método: Para doação de saliva foram selecionados vinte voluntários. Os voluntários permaneceram 24 horas sem escovar os dentes e ficaram em jejum por 2 horas antes da coleta da saliva. Foram avaliados os seguintes parâmetros: viabilidade das bactérias anaeróbias totais e mutans streptococci; concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) da clorexidina; capacidade de formação de biofilme por meio da biomassa; e a suscetibilidade dos biofilmes à clorexidina. Resultado: A viabilidade bacteriana da saliva, a capacidade de formação de biofilme e a suscetibilidade do biofilme à clorexidina foram apresentadas como média e intervalo de confiança (95%). A diferença entre a viabilidade do biofilme (mutans streptococci e bactérias totais) após tratamento com NaCl 0,9% e diacetato de clorexidina 0,2% foi comparada pelo teste t de Student com nível de significância estabelecido em 5%. A viabilidade total de bactérias anaeróbias (mediana) foi de 7,28 log 1+UFC/mL (unidades formadoras de colônia/mL). A viabilidade dos mutans streptococci na saliva apresentou mediana de 5,47 log 1+UFC/mL. Para capacidade de formação de biofilme a mediana da biomassa foi de 0,1172 A570. Conclusão: O tratamento com clorexidina reduziu significativamente os mutans streptococci e a viabilidade total das bactérias. A metodologia para seleção do doador de saliva foi estabelecida com sucesso.

Introduction: The utilization of polymicrobial biofilms, with saliva as an inoculum, represents a promising model for in vitro studies on cariogenic biofilms. However, there is still no standardization for selecting saliva donors. Objective: The aim of this study is to establish a methodology for the selection of saliva donors using microbial salivary factors and in vitro biofilm characteristics. Material and method: For saliva donation, twenty volunteers were selected. Volunteers remained 24 h without brushing their teeth and fasted for 2 h before saliva collection. The following parameters were evaluated: total anaerobic bacteria and mutans streptococci viability; minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC) of chlorhexidine; biofilm forming capacity by biomass assessment; and the susceptibility of biofilms to chlorhexidine. Result: Saliva bacterial viability, biofilm forming capacity and biofilm susceptibility to chlorhexidine were presented as mean and confidence interval (95%). The difference between biofilm (mutans streptococci and Total bacteria) viability after treatment with NaCl 0.9% and 0.2% chlorhexidine diacetate was compared using the Student t-test with a significance level established at 5%. Total anaerobic bacteria viability (median) was 7.28 log 1+CFU/mL (colony forming units/ mL). Mutans streptococci viability in the saliva showed a median of 5.47 log 1+CFU/mL. Biofilm forming capacity showed that biomass had a median of 0.1172 A570. Conclusion: Treatment with chlorhexidine significantly reduced mutans streptococci and total bacteria viability. The methodology for the selection of the saliva donor was successfully established.

Nicotine is a potent extracellular polysaccharide inducer in Fusobacterium nucleatum biofilms

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides

Biofilme na indústria de alimentos: micro-organismos envolvidos e métodos de controle / Biofilm in the food industry: micro-organisms involved and control methods

Os biofilmes podem acarretar vários problemas em diversas áreas, principalmente na indústria alimentícia, já que sua colonização nas superfícies como aço inoxidável, polietileno, polipropileno, podem contaminar produtos, causando sua deterioração, além de possibilitar diversas doenças transmitidas por alimentos. A formação de biofilme pode ocorrer em diferentes tipos de superfícies e pode envolver diversos micro-organismos. Práticas adequadas de higienização na indústria de alimentos são fundamentais para manter medidas seguras de preservação da qualidade dos alimentos. Portanto, o presente estudo objetiva realizar levantamento bibliográfico para explanar a formação e caracterização de biofilmes, ressaltando sua importância na indústria de alimentos e os métodos de prevenção de biofilmes disponíveis. Pode-se observar a necessidade de novas tecnologias no controle e erradicação de Biofilmes.

Biofilms can cause several problems in different areas, especially in food, as their colonization on surfaces in industries such as stainless steel, polyethylene, polypropylene, can contaminate products, causing their deterioration, in addition to making various food-borne diseases possible. Biofilm formation can occur on different types of surfaces and can involve different microorganisms. Adequate hygiene practices in the food industry are essential to maintain safe measures to preserve food quality. Therefore, the present study aims to carry out a bibliographical survey to explain the formation and characterization of biofilms, highlighting the importance in the food industry and the available biofilm prevention methods. The need for new technologies in the control and eradication of Biofilms can be observed.

Antibacterial Efficacy of Silver Diamine Fluoride Compared to Casein Phosphopeptide-Amorphous Calcium Phosphate Against Streptococcus mutans in a Biofilm Caries Model

ABSTRACT Objective: To compare the antibacterial efficacy of silver diamine fluoride (SDF) with a product containing casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) against Streptococcus mutans using a biofilm caries model. Material and Methods: Twenty-seven saliva-coated dentine blocks obtained from extracted human teeth were inoculated with Streptococcus mutans monospecies biofilm in this in vitro study. The biofilms were then exposed to 10% sucrose in brain heart infusion broth eight times daily for seven days. After the biofilm growth period, the dentine blocks (n=9 per group) were treated with one of the following substances: 1) sterile saline (control), 2) 38% SDF, and 3) a product containing CPP-ACP. Then, the samples were incubated at 37ºC for 48 hours, and the numbers of viable microorganisms in the biofilms were counted and compared. ANOVA and Tukey's HSD tests were used to analyze the data (p<0.05). Results: The number of viable bacteria, as determined by the number of colony-forming units (CFU mL-1) of Streptococcus mutans, was significantly reduced following treatment with SDF and the CPP-ACP product (p<0.05). However, SDF showed superior antibacterial activity compared to the CPP-ACP product (mean CFU mL-1 =zero compared to 96 x106) (p<0.05). Conclusion: SDF has higher antibacterial activity against cariogenic Streptococcus mutans biofilm than the CPP-ACP product. The CPP-ACP product showed antibacterial activity, but it was limited.

Safe duration of silicon catheter replacement in urological patients

Objectives: This study compared the infection rates, degree of encrustation, symptoms, and complications in patients regarding the duration of urethral catheterisation (three weeks, six weeks, and eight weeks). Design: A cross-sectional study with stratified simple random sampling Setting: Urology Unit, Korle Bu Teaching Hospital Participants: One hundred and thirty-seven male patients with long-term urinary catheters Interventions: Participants were grouped into 3 weeks, 6 weeks, and 8 weeks duration of catheter replacementsPrimary outcomes measures: Symptoms due to the urinary catheters, urinalysis, urine and catheter tip cultures, sensitivity, and catheter encrustations were assessed. Results: Eighty-six patients had a primary diagnosis of benign prostatic hyperplasia (BPH), 35 had urethral strictures,13 had prostate cancer, two had BPH and urethral strictures, and one participant had bladder cancer. There was no difference in the symptoms the participants in the different groups experienced due to the urinary catheters (p > 0.05). The frequency of occurrence of complications (pyuria, p = 0.784; blocked catheter, p=0.097; urethral bleeding, p=0.148; epididymo-orchitis, p=0.769 and bladder spasms, p=1.000) showed no differences in the three groups. There was no statistical difference in the urinalysis for the three groups (p>0.05) and the degree of encrustations (3 weeks: 0.03 ± 0.06, 6 weeks: 0.11±0.27 and eight weeks: 0.12 ±0.27) with p=0.065. Conclusions: In this study, the duration of urinary catheterisation using silicone Foley's catheters did not influence the complication and symptom rates; hence silicon catheters can be placed in situ for up to 8 weeks before replacement instead of the traditional three-weekly change.

Levofloxacin combined with cellulase can eradicate bacille Calmette-Guerin biofilm infection / 南方医科大学学报

OBJECTIVE@#To investigate the inhibitory effects of levofloxacin (LEV) combined with cellulase against bacille CalmetteGuerin (BCG) biofilms in vitro.@*METHODS@#The mature growth cycle of BCG biofilms was determined using the XTT method and crystal violet staining. BCG planktonic bacteria and BCG biofilms were treated with different concentrations of LEV and cellulose alone or jointly, and the changes in biofilm biomass were quantified with crystal violet staining. The mature BCG biofilm was then treated with cellulase alone for 24 h, and after staining with SYTO 9 and Calcofluor White Stain, the number of viable bacteria and the change in cellulose content in the biofilm were observed with confocal laser scanning microscopy. The structural changes of the treated biofilm were observed under scanning electron microscopy.@*RESULTS@#The MIC, MBC and MBEC values of LEV determined by broth microdilution method were 4 μg/mL, 8 μg/mL and 1024 μg/mL, respectively. The combined treatment with 1/4×MIC LEV and 2.56, 5.12 or 10.24 U/mL cellulase resulted in a significant reduction in biofilm biomass (P < 0.001). Cellulase treatments at the concentrations of 10.24, 5.12 and 2.56 U/mL all produced significant dispersion effects on mature BCG biofilms (P < 0.001).@*CONCLUSION@#LEV combined with cellulose can effectively eradicate BCG biofilm infections, suggesting the potential of glycoside hydrolase therapy for improving the efficacy of antibiotics against biofilmassociated infections caused by Mycobacterium tuberculosis.

Evaluation of methanolic crude extract of Linum usitatissimum for the removal of biofilm in diabetic foot isolates / Avaliação do extrato em bruto metanólico de Linum usitatissimum para remoção de biofilmes em isolados diabéticos de pé

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.

In vitro antibacterial and antibiofilm activities of Piper betle L. ethanolic leaf extract on staphylococcus aureus ATCC 29213

Background and Objective@#Staphylococcus aureus is the leading cause of skin and soft tissue infections such as abscesses, furuncles, and cellulitis. Biofilm forming strains of S. aureus have higher incidence of antimicrobial resistance to at least three or more antibiotics and are considered as multidrug resistant. Since S. aureus biofilm-producing strains have higher rates of multidrug and methicillin resistance compared to non-biofilm-producing strains, the need for alternative therapeutic option is important. Furthermore, rates of methicillin-resistant Staphylococcus aureus (MRSA) in Asia remain high. Results of the study may provide support for the clinical uses of P. betle as a topical antibacterial and antiseptic in the treatment and prevention of infections involving the skin, mouth, throat, and indwelling medical devices. Thus, this study aimed to evaluate the in vitro antibacterial and antibiofilm activities of Piper betle L. ethanolic leaf extract (PBE) against a biofilm-forming methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA).@*Methods@#The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of PBE against MSSA were determined using the agar dilution assay. The biofilm inhibition and eradication assays using crystal violet were done to quantify the antibiofilm activities of PBE on MSSA biofilm.@*Results@#PBE showed activity against MSSA in agar dilution assay with MIC and MBC values of 2500 μg/mL and 5000 μg/mL, respectively. At subinhibitory concentrations, PBE showed biofilm inhibition activity at 1250 μg/mL but a lower percent eradication of biofilms as compared to oxacillin was noted.@*Conclusion@#PBE showed antibacterial activities including biofilm inhibition against methicillin-sensitive Staphylococcus aureus ATCC 29213 (MSSA).

Evaluation of methanolic crude extract of Linum usitatissimum for the removal of biofilm in diabetic foot isolates / Avaliação do extrato em bruto metanólico de Linum usitatissimum para remoção de biofilmes em isolados diabéticos de pé

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.

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.

Oligonucleotide drugs and their progress in stomatology / 中华口腔医学杂志

Oligonucleotide drugs have the characteristics of targeting, modifiability and high biosafety. Recent studies have shown that oligonucleotide can be used to make biosensors, vaccine adjuvants, and has the functions of inhibiting alveolar bone resorption, promoting jaw and alveolar bone regeneration, anti-tumor, destroying plaque biofilm, and precise control of drug release. Therefore, it has a broad application prospect in the field of stomatology. This article reviews the classification, action mechanism and research status of oligonucleotide in stomatology. The aim is to provide ideas for further research and application of oligonucleotide.

Antibacterial effect of low-temperature plasma on Enterococcus faecalis in dentinal tubules in vitro / 北京大学学报(医学版)

OBJECTIVE@#To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules.@*METHODS@#Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma.@*RESULTS@#The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600μm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure.@*CONCLUSION@#Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.

Advances in electrochemically active biofilm of Shewanella oneidensis MR-1 / 生物工程学报

Facing the increasingly severe energy shortage and environmental pollution, electrocatalytic processes using electroactive microorganisms provide a new alternative for achieving environmental-friendly production. Because of its unique respiratory mode and electron transfer ability, Shewanella oneidensis MR-1 has been widely used in the fields of microbial fuel cell, bioelectrosynthesis of value-added chemicals, metal waste treatment and environmental remediation system. The electrochemically active biofilm of S. oneidensis MR-1 is an excellent carrier for transferring the electrons of the electroactive microorganisms. The formation of electrochemically active biofilm is a dynamic and complex process, which is affected by many factors, such as electrode materials, culture conditions, strains and their metabolism. The electrochemically active biofilm plays a very important role in enhancing bacterial environmental stress resistance, improving nutrient uptake and electron transfer efficiency. This paper reviewed the formation process, influencing factors and applications of S. oneidensis MR-1 biofilm in bio-energy, bioremediation and biosensing, with the aim to facilitate and expand its further application.

Control de la caries no restaurativa en incisivos centrales primarios, a los 36 meses de seguimiento / Controle cavitário não restaurador em incisivos centrais decíduos com 36 meses de acompanhamento / Non-restorative cavity control in deciduous central incisors at 36-month follow-up

La mínima intervención ha ido ganando cada vez más notoriedad en la Odontología, reflejando una creciente demanda por parte de los profesionales que buscan técnicas que promuevan tratamientos eficientes y que preserven la estructura dentaria. Objetivo: El presente estudio tuvo como objetivo promover el control de caries no restaurador (CCNR) en un paciente infantil, mediante una regularización de la cavidad de la lesión cariosa para permitir una mejor limpieza del área, junto con un protocolo complementario de fluoración. Presentación de caso: Paciente masculino de 4 años de edad con higiene bucal satisfactoria, sin embargo con acumulación de biopelícula entre los incisivos centrales superiores y sin síntomas ni quejas estéticas. Se alisaron las caras mesiales de los incisivos centrales con tiras abrasivas para eliminar zonas socavadas y facilitar el acceso para mejorar la higiene bucal, y se aplicó el barniz de flúor en 4 sesiones, con un intervalo de una semana entre cada aplicación. La madre de la paciente fue instruida sobre cuidados de higiene y alimentación. Durante 36 meses se realizó seguimiento clínico y radiográfico del paciente con retornos cada 12 meses. También se reevaluaron el índice de placa visible y los resultados de la guía de higiene y dieta. Conclusión; En este caso clínico, la fluorterapia asociada a la regularización superficial demostró ser una alternativa de tratamiento exitosa a largo plazo, permitiendo la preservación del tejido dentario y previniendo la progresión de las lesiones cariosas. El concepto ultraconservador puede ser una alternativa válida por su eficacia, sencillez, bajo coste y buena aceptación por parte de los niños y sus padres

A mínima intervenção vem ganhando cada vez mais notoriedade na Odontologia, refletindo uma crescente demanda de profissionais que buscam por técnicas que promovam tratamentos eficientes e preservem a estrutura dental. Objetivo: O presente estudo teve como objetivo promover um controle cavitário não restaurador (CCNR) em um paciente infantil, por meio de uma regularização da cavidade da lesão de cárie para permitir uma melhor higienização da área, associado a um protocolo complementar de flúor. Caso clinico: Paciente do sexo masculino, 4 anos de idade, com higiene bucal regular, entretanto com acúmulo de biofilme entre os incisivos centrais superiores e sem sintomatologia ou queixa estética. As superfícies mesiais dos incisivos centrais foram regularizadas com tiras abrasivas para remover áreas retentivas e facilitar o acesso para melhorar a higiene bucal. O verniz fluoretado foi aplicado em 4 sessões, com intervalo de uma semana entre cada aplicação. A mãe do paciente foi orientada quanto à higiene e cuidados com a dieta. Durante 36 meses, houve o acompanhamento clínico e radiográfico do paciente com retornos a cada 12 meses. O índice de placa visível e os resultados da orientação de higiene e dieta também foram reavaliados. Conclusão: Neste caso clínico, a regularização de superfícies associada a fluorterapia, mostrou-se uma alternativa de tratamento de sucesso a longo prazo, permitindo a preservação do tecido dentário e impedindo a progressão das lesões de cárie. O conceito ultraconservador pode ser uma alternativa válida devido à sua eficácia, simplicidade, baixo custo e boa aceitação pelas crianças e seus pais.

The minimal intervention has been gaining more notoriety in Dentistry, reflecting growing demand from professionals looking for techniques that promote efficient treatments and preserve the dental structure. Objective: The present study aimed to promote non-restorative cavity control (CCNR) in a child patient through regularization of the cavity of the carious lesion to allow better cleaning of the area, together with a complimentary fluoride protocol. Case presentation: Male patient, 4 years old, presenting adequate oral hygiene. However, biofilm accumulation occurs between the upper central incisors without symptoms or aesthetic complaints. Therefore, the mesial surfaces of the central incisors were smoothed with abrasive strips to remove undercut areas and facilitate access to improve oral hygiene. The fluoride varnish was applied in 4 sessions, with an interval of one week between each application. The patient's mother was instructed on hygiene and diet care. During 36 months, there was a clinical and radiographic follow-up of the patient with returns every 12 months. The visible plaque index and the hygiene and diet guidance results were also re-evaluated. Conclusion: In this clinical case, surface regularization associated fluortherapy proved to be a successful long-term treatment alternative, allowing the preservation of dental tissue and preventing the progression of caries lesions. The ultra-conservative concept can be a valid alternative due to its effectiveness, simplicity, low cost, and good acceptance by children and their parents.

Analysis of biofilm formation by Candida albicans in different types of orthodontic fixed appliances and devices / Análise da formação de biofilme por Candida albicans em diferentes tipos de aparelhos e dispositivos ortodônticos fixos

Objective: in this study, biofilm formation by Candida albicans in fixed orthodontic appliances was evaluated. Material and Methods: a total of 300 conventional metal brackets (MC), ceramic (CB), self-ligation (SLB), nickel-titanium (NiTi), and nickel-chromium (NiCr) wires, and ligatures types were organized into thirty groups (n=10). To induce biofilm formation, brackets, wires, and ligatures were joined, sterilized, placed in 24-well plates, contaminated with standardized suspensions of C. albicans (107 cells/mL), and incubated at 37 °C for 48 h with shaking. The biofilms formed were detached using an ultrasonic homogenizer, and suspensions were serially diluted and plated on Sabouraud dextrose agar to determine colony-forming units per mL. Scanning electron microscopy was performed before and after the biofilm formation. Results: lower amount of biofilm formation was observed in the MC group than in the CB and SLB groups (p<0.0001). SLB and CB showed similar biofilm formation rates (p=0.855). In general, the cross-sectional wires .018"x.025" showed higher biofilm formation when associated with the three types of brackets. When brackets, wires, and ligatures were associated, the sets with NiCr wires and SSL ligatures with MC brackets (p=0.0008) and CB (p=0.0003) showed higher biofilm formation. Conclusion: thus, brackets of MC with NiTi and NiCr wires showed lower biofilm formation, regardless of the ligature and cross-sectional or gauge of the wire and, MC and CB brackets with NiCr wires and SSL ligatures were more likely to accumulate biofilms (AU)

Objetivo: neste estudo, a formação de biofilme por Candida albicans em aparelhos ortodônticos fixos foi avaliada. Material e Métodos: um total de 300 bráquetes metálicos convencionais (MC), cerâmicos (CB), autoligados (SLB), com fios de níquel-titânio (NiTi) e níquel-cromo (NiCr) e tipos de ligaduras foram organizados em trinta grupos (n=10). Bráquetes, fios e ligaduras foram unidos, esterilizados, colocados em placas de 24 poços, contaminados com suspensões padronizadas de C. albicans (107 células/mL) e incubados a 37°C por 48 h para a formação de biofilmes. Os biofilmes formados foram rompidos por meio de um homogeneizador ultrassônico e suspensões foram diluídas e semeadas em ágar Sabouraud-dextrose para determinar as unidades formadoras de colônias por mL. A microscopia eletrônica de varredura foi realizada antes e após a formação do biofilme. Resultados: foi observada menor formação de biofilme no grupo MC em comparação aos grupos CB e SLB (p<0,0001). A formação de biofilme foi semelhante nos grupos SLB e CB (p=0,855). Em geral, os fios de seção transversal .018"x.025" apresentaram maior formação de biofilme quando associados aos três tipos de bráquetes. Os conjuntos com fios de NiCr e ligaduras SSL com bráquetes MC (p=0,0008) e CB (p=0,0003) apresentaram maior formação de biofilme. Conclusão: bráquetes MC com fios de NiTi e NiCr apresentaram menor formação de biofilme, independente da ligadura e secção transversal ou bitola do fio e, braquetes MC e CB com fios de NiCr e ligaduras SSL foram mais propensos a acumular biofilmes.(AU)