A feasible in vitro method to evaluate bacterial infiltration in three implant-abutment connection systems / Método in vitro factible para evaluar la infiltración bacteriana en tres sistemas de conexión implante-pilar

Introduction: Microorganism infiltration through the im-plant-abutment interface causes oral health problems such as periimplantitis, leading to implant loss. Materials and Methods: A feasible new method to quantify the Streptococcus mutans (S. mutans) infiltration through the implant-abutment interface gap is introduced in the present work. Internal hexagon (IH; n = 10), external hexagon (EH; n = 10), Morse taper (MT; n = 10), and a control for each group (n = 1) were tested. Bacteria suspension was prepared at 1.5x108 CFU/mL (CFU: colony forming units), and the implants were individually submerged up to the connection level, allowing the bacteria to contact it. The abutment was removed, and bacteria count was performed. Results: The implant sets were tested under normal bacterial growth and early and late biofilm growth conditions. Colony-forming units per mL were obtained, and the results were compared among groups. Differences in bacterial count between the MT and EH (p<0.001) and the MT and IH (p<0.001) groups were significantly higher in the MT-type implant. There was a significant increment of bacterial infiltration in the MTs submitted to late biofilm growth conditions. EH and IH connections are more effective in preventing bacterial infiltration independent of the growth condition. Conclusions: The proposed methodology is feasible to evaluate the infiltration of microorganisms through the implant-abutment interface.

Introducción: La infiltración de microorganismos a través de la interfaz implante-pilar provoca problemas de salud bucal como la periimplantitis, que conduce a la pérdida del implante. Materiales y Métodos: En el presente trabajo se presenta un nuevo método factible para cuantificar la infiltración de Streptococcus mutans (S. mutans) a través de la brecha de la interfaz implante-pilar. Se probaron el hexágono interno (IH; n = 10), el hexágono externo (EH; n = 10), el cono Morse (MT; n = 10) y un control para cada grupo (n = 1). Se preparó una suspensión de bacterias a 1,5x108 UFC/mL y los implantes se sumergieron individualmente hasta el nivel de conexión, permitiendo que las bacterias entraran en contacto con él. Resultados: Se retiró el pilar y se realizó recuento de bacterias. Los conjuntos de implantes se probaron en condiciones de crecimiento bacteriano normal y de crecimiento temprano y tardío de biopelículas. Se obtuvieron unidades formadoras de colonias por ml y los resultados se compararon entre grupos. Las diferencias en el recuento bacteriano entre los grupos MT y EH (p<0,001) y MT e IH (p<0,001) fueron significativamente mayores en el implante tipo MT. Hubo un incremento significativo de la infiltración bacteriana en los MT sometidos a condiciones tardías de crecimiento de biopelículas. Las conexiones EH e IH son más efectivas para prevenir la infiltración bacteriana independientemente de las condiciones de crecimiento. Conclusión: La metodología propuesta es factible para evaluar la infiltración de microorganismos a través de la interfaz implante-pilar.

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.

Biological sealing aspects surrounding anterior crowns on dental implants: clinical and photographic cases report

The biological sealing (BS) around implants is a dominant factor to determine the long-term success of peri-implant health. There are several features of the BS around implants in common with the soft tissue attached to teeth, such as the presence of crevicular fluid, acquired pellicle, epithelium; otherwise, the quality of the BS around implants is weaker compared with the junctional epithelium of natural teeth. Then, this article aimed to describe three cases report showing the presence of a BS (cuticle-crevice fluid-acquired pellicle) around the fixed crowns on dental implants in the anterior zone, through photographic analysis. It was used a Nikon 8100 camera with a 105 mm macro lens and a Macro Ring circular flash. A photographic profile examination was made always showing the clinical case and, specifically, the focal point in the crown-gingival tissue (prosthesis boundary and peri-implant tissue), highlighting the anatomical gingiva on the ceramic prosthetic crown at an angle between 140 to 160 degrees. Although cases 1 and 2 had 1-year follow-up and case 3 around 4 years, the common findings for all treatments done were: (i) oral rehabilitation with crowns on dental implants; (ii) patients satisfied with the esthetic and functional result; (iii) stability of the soft tissue around the crowns; (iv) all the patients had a good oral hygiene; (v) presence of a thin membrane associated with the acquire pellicle, similar to an annular cuticle, which we named cuticle-acquired pellicle complex or tertiary cuticle or prosthetic-implant cuticle. This complex (cuticle-crevicular fluid-acquired pellicle) is suggested to be the responsible by the BS on dental implants. Moreover, the cuticle (epithelial part in the peri-implant sulcus), although similar to teeth, may be considered a tertiary pellicle due to be found on ceramic crowns on dental implants, differently of the primary and secondary pellicle. Whitin the limitation of these three cases reports, the BS was reported and can be introduced the new concept of the "cuticle-crevicular fluid-acquired pellicle complex" or "prosthetic-implant cuticle".

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.

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.

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.

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.

Removal effect of disinfection factors in low concentration on Pseudomonas aeruginosa biofilm / 中华预防医学杂志

Experimental model of Pseudomonas aeruginosa biofilm was established in vitro by using biofilm reactor. The aim of this study was evaluating the removal effect of two kinds of water flowing through bactericide resin on Pseudomonas aeruginosa biofilm, and exploring the effectiveness of continuous treatment with low concentration disinfection factor on dental unit waterlines. The experimental group selected 1-2 mg/L iodinated resin (IR) filtered water and bromined hydantoin resin (BHR) filtered water with the control group selecting the sterile distilled water. Biofilms were treated by using the immersion method for 3, 7, 10, 20, and 40 days. Total viable count (TVC) and laser confocal microscopy method (CLSM) were selected to evaluate the biofilm removal effect. The result of TVC showed that in group IR, the bacterial clearance after the treatment of 3, 7, 10, and 20 days was lower than 99.9% and unqualified. The bacterial clearance after the treatment of 40 days was 99.9%,which is qualified. In group BHR, it was lower than 99.9% and unqualified after the treatment of 3, 7, and 10 days. It was and 99.99%, 100.00% after the treatment of 20, 40 days, respectively. The result of CLSM showed that before treatment, Pseudomonas aeruginosa biofilm showed a sheet and mass distribution. The bacterial coverage was 19.24%±1.97%. The proportion of viable bacteria was 93.91%±1.39%, and the biofilm matrix coverage was 17.69%±1.11%. After 20 days of treatment, the biofilm was decreased in the IR group, with the biofilm bacterial coverage reducing to 6.77%±1.61%, the proportion of live bacteria reducing to 54.85%±5.65%, and the biofilm matrix coverage reducing to 2.41%±0.85%.There was significant difference from the pre-treatment and the control (F=359.996,P<0.001). No biofilm-like structure was found in the BHR group. After 40 days of treatment, there was still a small amount of biofilm matrix residue in the IR group, with no bacterial coverage observed. The biofilm matrix coverage was 0.67%±0.47% (F=1 021.373,P<0.001). No biofilm-like structure was found in the BHR group. In conclusion, the continuous application of BHR filter water has more advantages in killing microorganisms in biofilms, removing live and dead bacteria and biofilm matrix in biofilms. Treatment water containing corresponding low concentration disinfection factors can play an important role in the field of biofilm control in dental unit waterlines.

Antimicrobials discovery against Staphylococcus aureus by high throughput screening of drug library / 中华预防医学杂志

To develop antimicrobials against Staphylococcus aureus by high throughput screening of drug library. The type of this study is experimental research. The clinical isolates of S. aureus were collected from the sputum samples of respiratory inpatient department of the Third Xiangya Hospital of Central South University. The anti-planktonic cells growth inhibition activity of FDA-approved drugs library (including 1 573 molecules) was assessed by building a planktonic cells screening platform; The biofilm inhibitory effect of the FDA-approved drugs was detected by building a biofilm screening platform combined with crystal violet staining; Minimal inhibitory concentrations of the selected hits were determined by broth microdilution assay. Finally, the cytotoxicity of the selected hits was detected by CCK-8 assay. The results showed that 218 hits were exhibited effective growth inhibitory effects against S. aureus by setting the concentrations of the molecules in the FDA-approved library to 100 μmol/L. These selected molecules are mainly anti-infective drugs, accounting for 118 hits; Followed by anti-cancer drugs, anti-inflammatory/-immune drugs, neurological drugs, cardiovascular drugs, endocrine drugs, and metabolic disease drugs, which accounts for 40, 19, 12, 9, 8, and 3 hits; Other unclassified drugs accounts for 9 hits. The top 10 hits exhibiting anti-planktonic cells activity against S. aureus were mainly including antitumor drugs, followed by neurological drugs and unclassified drugs like vitamin K3 with the inhibition rate of 99.65%-100%. Similarly, the top 10 hits showing biofilm inhibitory effects against S. aureus were also mainly including antitumor drugs, followed by neurological drugs and anti-inflammatory/-immune drugs with the inhibition rate of 50.22%-92.95%. The minimal inhibitory concentration (MIC) of the 51 hits by second round screening was determined by micro-dilution assay, which mainly include the antitumor drugs, cardiovascular drugs, endocrine drugs, anti-inflammatory/-immune drugs, metabolic disease drugs, neurological drugs and other unclassified drugs accounted for 22, 5, 3, 9, 2, 5 and 5 hits, respectively, with the MICs of 1.56-50 μmol/L, 6.25-25 μmol/L, 6.25-25 μmol/L, 0.2-50 μmol/L, 25-50 μmol/L, 1.56-50 μmol/L and 0.1-12.5 μmol/L, respectively. In conclusion, the minimum inhibitory concentrations of small molecules screened through high-throughput assay are at the level of micromolar with strong drug development potential and high modifiability. The high effective anti-planktonic cells and anti-biofilm activity by these molecules are expected to provide new ideas for the development of new antimicrobials against S. aureus.

Removal effect of disinfection factors in low concentration on Pseudomonas aeruginosa biofilm / 中华预防医学杂志

Experimental model of Pseudomonas aeruginosa biofilm was established in vitro by using biofilm reactor. The aim of this study was evaluating the removal effect of two kinds of water flowing through bactericide resin on Pseudomonas aeruginosa biofilm, and exploring the effectiveness of continuous treatment with low concentration disinfection factor on dental unit waterlines. The experimental group selected 1-2 mg/L iodinated resin (IR) filtered water and bromined hydantoin resin (BHR) filtered water with the control group selecting the sterile distilled water. Biofilms were treated by using the immersion method for 3, 7, 10, 20, and 40 days. Total viable count (TVC) and laser confocal microscopy method (CLSM) were selected to evaluate the biofilm removal effect. The result of TVC showed that in group IR, the bacterial clearance after the treatment of 3, 7, 10, and 20 days was lower than 99.9% and unqualified. The bacterial clearance after the treatment of 40 days was 99.9%,which is qualified. In group BHR, it was lower than 99.9% and unqualified after the treatment of 3, 7, and 10 days. It was and 99.99%, 100.00% after the treatment of 20, 40 days, respectively. The result of CLSM showed that before treatment, Pseudomonas aeruginosa biofilm showed a sheet and mass distribution. The bacterial coverage was 19.24%±1.97%. The proportion of viable bacteria was 93.91%±1.39%, and the biofilm matrix coverage was 17.69%±1.11%. After 20 days of treatment, the biofilm was decreased in the IR group, with the biofilm bacterial coverage reducing to 6.77%±1.61%, the proportion of live bacteria reducing to 54.85%±5.65%, and the biofilm matrix coverage reducing to 2.41%±0.85%.There was significant difference from the pre-treatment and the control (F=359.996,P<0.001). No biofilm-like structure was found in the BHR group. After 40 days of treatment, there was still a small amount of biofilm matrix residue in the IR group, with no bacterial coverage observed. The biofilm matrix coverage was 0.67%±0.47% (F=1 021.373,P<0.001). No biofilm-like structure was found in the BHR group. In conclusion, the continuous application of BHR filter water has more advantages in killing microorganisms in biofilms, removing live and dead bacteria and biofilm matrix in biofilms. Treatment water containing corresponding low concentration disinfection factors can play an important role in the field of biofilm control in dental unit waterlines.

Antimicrobials discovery against Staphylococcus aureus by high throughput screening of drug library / 中华预防医学杂志

To develop antimicrobials against Staphylococcus aureus by high throughput screening of drug library. The type of this study is experimental research. The clinical isolates of S. aureus were collected from the sputum samples of respiratory inpatient department of the Third Xiangya Hospital of Central South University. The anti-planktonic cells growth inhibition activity of FDA-approved drugs library (including 1 573 molecules) was assessed by building a planktonic cells screening platform; The biofilm inhibitory effect of the FDA-approved drugs was detected by building a biofilm screening platform combined with crystal violet staining; Minimal inhibitory concentrations of the selected hits were determined by broth microdilution assay. Finally, the cytotoxicity of the selected hits was detected by CCK-8 assay. The results showed that 218 hits were exhibited effective growth inhibitory effects against S. aureus by setting the concentrations of the molecules in the FDA-approved library to 100 μmol/L. These selected molecules are mainly anti-infective drugs, accounting for 118 hits; Followed by anti-cancer drugs, anti-inflammatory/-immune drugs, neurological drugs, cardiovascular drugs, endocrine drugs, and metabolic disease drugs, which accounts for 40, 19, 12, 9, 8, and 3 hits; Other unclassified drugs accounts for 9 hits. The top 10 hits exhibiting anti-planktonic cells activity against S. aureus were mainly including antitumor drugs, followed by neurological drugs and unclassified drugs like vitamin K3 with the inhibition rate of 99.65%-100%. Similarly, the top 10 hits showing biofilm inhibitory effects against S. aureus were also mainly including antitumor drugs, followed by neurological drugs and anti-inflammatory/-immune drugs with the inhibition rate of 50.22%-92.95%. The minimal inhibitory concentration (MIC) of the 51 hits by second round screening was determined by micro-dilution assay, which mainly include the antitumor drugs, cardiovascular drugs, endocrine drugs, anti-inflammatory/-immune drugs, metabolic disease drugs, neurological drugs and other unclassified drugs accounted for 22, 5, 3, 9, 2, 5 and 5 hits, respectively, with the MICs of 1.56-50 μmol/L, 6.25-25 μmol/L, 6.25-25 μmol/L, 0.2-50 μmol/L, 25-50 μmol/L, 1.56-50 μmol/L and 0.1-12.5 μmol/L, respectively. In conclusion, the minimum inhibitory concentrations of small molecules screened through high-throughput assay are at the level of micromolar with strong drug development potential and high modifiability. The high effective anti-planktonic cells and anti-biofilm activity by these molecules are expected to provide new ideas for the development of new antimicrobials against S. aureus.

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).

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.

Protein Containing the GGDEF Domain Affects Motility and Biofilm Formation in Vibrio cholerae and is Negatively Regulated by Fur and HapR / 生物医学与环境科学（英文）

OBJECTIVE@#This study aimed to investigate whether the VCA0560 gene acts as an active diguanylate cyclase (DGC) in Vibrio cholerae and how its transcription is regulated by Fur and HapR.@*METHODS@#The roles of VCA0560 was investigated by utilizing various phenotypic assays, including colony morphological characterization, crystal violet staining, Cyclic di-GMP (c-di-GMP) quantification, and swimming motility assay. The regulation of the VCA0560 gene by Fur and HapR was analyzed by luminescence assay, electrophoretic mobility shift assay, and DNase I footprinting.@*RESULTS@#VCA0560 gene mutation did not affect biofilm formation, motility, and c-di-GMP synthesis in V. cholerae, and its overexpression remarkably enhanced biofilm formation and intracellular c-di-GMP level but reduced motility capacity. The transcription of the VCA0560 gene was directly repressed by Fur and the master quorum sensing regulator HapR.@*CONCLUSION@#Overexpressed VCA0560 functions as an active DGC in V. cholerae, and its transcription is repressed by Fur and HapR.

Preparation, characterization and activity evaluation of Spirulina-chitooligosaccharides capable of inhibiting biofilms / 生物工程学报

The biofilms formed by pathogenic microorganisms seriously threaten human health and significantly enhance drug resistance, which urgently call for developing drugs specifically targeting on biofilms. Chitooligosaccharides extracted from shrimp and crab shells are natural alkaline oligosaccharides with excellent antibacterial effects. Nevertheless, their inhibition efficacy on biofilms still needs to be improved. Spirulina (SP) is a microalga with negatively charged surface, and its spiral structure facilitates colonization in the depth of the biofilm. Therefore, the complex of Spirulina and chitooligosaccharides may play a synergistic role in killing pathogens in the depth of biofilm. This research first screened chitooligosaccharides with significant bactericidal effects. Subsequently, Spirulina@Chitooligosaccharides (SP@COS complex was prepared by combining chitooligosaccharides with Spirulina through electrostatic adsorption. The binding of the complex was characterized by zeta potential, z-average size, and fluorescence labeling. Ultraviolet-visible spectroscopy (UV-Vis) showed the encapsulation efficiency and the drug loading efficiency reached up to 90% and 16%, respectively. The prepared SP@COS2 exhibited a profound synergistic inhibition effect on bacterial and fungal biofilms, which was mainly achieved by destroying the cell structure of the biofilm. These results demonstrate the potential of Spirulina-chitooligosaccharides complex as a biofilm inhibitor and provide a new idea for addressing the harm of pathogenic microorganisms.

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)

Ação antimicrobiana e antibiofilme dos extratos combinados de canela e própolis sobre cepas clínicas de Acinetobacter baumannii e Pseudomonas aeruginosa multirresistentes / Antimicrobial and antibiofilm action of combined extracts of cinnamon and propolis on multiresistant clinical strains of Acinetobacter baumannii and Pseudomonas aeruginosa

Os microrganismos resistentes a diferentes classes de agentes antimicrobianos têm se tornado cada vez mais comuns e atualmente são denominados como multirresistentes. Nos hospitais, tais microrganismos apresentam maior perigo, pois são causadores de infecções nosocomiais e a higienização bucal deficiente dos pacientes internados pode tornar a cavidade bucal um sítio para proliferação desses microrganismos multirresistentes. Diante do exposto, novos compostos com ação antimicrobiana precisam ser estudados. O objetivo deste estudo foi avaliar quimicamente o extrato hidroalcóolico de própolis verde de Baccharis dracunculifolia e de Cinnamomum verum (canela) que foram obtidos a partir da extração da matériaprima, analisar a atividade antimicrobiana e antibiofilme dos extratos isolados e combinados contra quatro cepas clínicas multirresistentes de Pseudomonas aeruginosa e Acinetobacter baumannii e verificar a citotoxicidade dos produtos vegetais in vitro em linhagem celular de queratinócitos humanos (HaCat). Para tanto, os extratos vegetais foram preparados a partir da matéria-prima da canela em casca e da própolis bruta. Em seguida, foram caracterizados quimicamente por cromatografia líquida de alta eficiência (HPLC-DAD) para identificação dos principais compostos e a análise do teor de sólidos solúveis dos extratos vegetais também foi realizada. Para avaliação antimicrobiana, foram performados o teste de microdiluição em caldo de acordo com a Clinical and Laboratory Standards Institute (CLSI) e a análise de Checkerboard, para avaliar o efeito combinado dos extratos. A atividade antibiofilme dos extratos combinados foi realizada por meio do teste de MTT, no qual diferentes tempos de contato (5 e 30 min) e diferentes modalidades (inibição na formação do biofilme bacteriano e erradicação do biofilme bacteriano já formado) foram testadas. Para ação citotóxica, as células foram cultivadas em meio DMEM e semeadas na placa de 96 poços. Após aderência inicial, aplicou-se os extratos em diferentes concentrações baseadas nas análises microbiológicas para avaliação da viabilidade celular por meio do teste de MTT. Os dados foram analisados por ANOVA e teste de Tukey, ou Kruskal-Wallis e Dunn, considerando um nível de significância de 5%. Os compostos identificados no extrato de própolis verde de B. dracunculifolia foram ácido clorogênico, derivado do ácido cinâmico e apigenina. O aldeído cinâmico foi o principal composto identificado no extrato de C. verum. Os extratos vegetais apresentaram ação bactericida sobre todas as cepas analisadas e, quando combinados, os extratos atuaram de modo aditivo e algumas combinações sinérgicas foram encontradas. O protocolo de inibição da formação do biofilme promoveu percentuais de redução superiores quando comparado ao protocolo de erradicação. Valores expressivos de 83,86% (p < 0,05) de inibição da formação de biofilme de uma cepa clínica de A. baumannii e 89,31% (p < 0,05) de inibição em uma cepa clínica de P. aeruginosa foram encontrados com a aplicação dos extratos combinados. A atuação dos produtos vegetais foi estatisticamente semelhante a atuação da clorexidina 0,12%. Em conclusão, os extratos de própolis verde e canela na forma isolada ou combinada apresentaram ação antimicrobiana e antibiofilme sobre cepas clínicas de A. baumannii e P. aeruginosa multirresistentes. Dessa forma, os produtos vegetais são promissores agentes antissépticos para futuras formulações odontológicas. (AU)

Microorganisms resistant to different classes of antimicrobial agents have become increasingly common and are currently called multidrug resistant. In hospitals, such microorganisms are more dangerous, as they cause nosocomial infections and poor oral hygiene in hospitalized patients can make the oral cavity a site for the proliferation of these multiresistant microorganisms. Given the above, new compounds with antimicrobial action need to be studied. The objective of this study was to chemically evaluate the hydroalcoholic extract of green propolis from Baccharis dracunculifolia and Cinnamomum verum (cinnamon) that were obtained from the extraction of the raw material, to analyze the antimicrobial and antibiofilm activity of the isolated and combined extracts against four clinical strains multiresistant strains of Pseudomonas aeruginosa and Acinetobacter baumannii and verify the cytotoxicity of plant products in vitro in human keratinocyte cell lineage (HaCat). For this purpose, plant extracts were prepared from raw cinnamon bark and raw propolis. Then, they were chemically characterized by high performance liquid chromatography (HPLC-DAD) to identify the main compounds and the analysis of the soluble solids content of the plant extracts was also performed. For antimicrobial evaluation, the broth microdilution test according to the Clinical and Laboratory Standards Institute (CLSI) and the Checkerboard analysis were performed to evaluate the combined effect of the extracts. The antibiofilm activity of the combined extracts was performed using the MTT test, in which different contact times (5 and 30 min) and different modalities (inhibition of bacterial biofilm formation and eradication of already formed bacterial biofilms) were tested. For cytotoxic action, cells were cultured in DMEM medium and seeded in the 96-well plate. After initial adhesion, the extracts were applied at different concentrations based on microbiological analyzes to assess cell viability through the MTT test. Data were analyzed by ANOVA and Tukey's test, or Kruskal-Wallis and Dunn, considering a significance level of 5%. The compounds identified in the green propolis extract of B. dracunculifolia were chlorogenic acid, cinnamic acid derivative and apigenin. Cinnamic aldehyde was the main compound identified in the C. verum extract. The plant extracts showed bactericidal action on all strains analyzed and, when combined, the extracts acted additively and some synergistic combinations were found. The biofilm formation inhibition protocol promoted higher reduction percentages when compared to the eradication protocol. Significant values of 83.86% (p < 0.05) inhibition of biofilm formation in a clinical strain of A. baumannii and 89.31% (p < 0.05) inhibition in a clinical strain of P. aeruginosa were found with the application of the combined extracts. The performance of plant products was statistically similar to the performance of 0.12% chlorhexidine. In conclusion, extracts of green propolis and cinnamon, in isolated or combined form, showed antimicrobial and antibiofilm action on multiresistant clinical strains of A. baumannii and P. aeruginosa. Thus, plant products are promising antiseptic agents for future dental formulations. (AU)

Ação antimicrobiana de extratos de gengibre (Zingiber officinale) e quilaia (Quillaja saponaria) isolados e associados sobre Pseudomonas aeruginosa resistente a antibióticos / Antimicrobial action of isolated and associated extracts of ginger (Zingiber officinale) and quilaia (Quillaja saponaria) on antibiotic-resistant Pseudomonas aeruginosa

Extratos de plantas têm demonstrado diversos efeitos positivos para a saúde, incluindo ação antimicrobiana, no entanto, o uso clínico da fitoterapia ainda é discreto, de modo que mais estudos sobre os efeitos benéficos do sinergismo farmacológico de extratos poderiam contribuir para sua aplicação terapêutica. O objetivo deste estudo foi avaliar os efeitos dos extratos glicólicos de gengibre (EG) e quilaia (EQ) isolados e em associação sobre 7 cepas clínicas de Pseudomonas aeruginosa e uma cepa padrão em forma planctônica e biofilmes monotípicos. Para a análise antimicrobiana sobre cultura planctônica foram feitos testes para determinação de Concentração Inibitória Mínima (CIM) e Concentração Microbicida Mínima (CMM) (CLSI, M07-A9) dos extratos isolados, além do Índice de Concentração Inibitória Fracionada (ICIF) e do Índice de Concentração Microbicida Fracionada (ICMF) para os extratos combinados. A análise estatística foi feita com método ANOVA e teste de Tukey para dados com distribuição normal e Kruskall-Wallis com Teste de Comparação Múltipla de Dunn para dados sem distribuição normal (significância de 5%). Para cepa padrão foram determinadas CIM igual a 3,12 mg/mL e CMM igual a 6,25 mg/mL para ambos os extratos. Para cepas clínicas as CIM do EG foram 3,12 ou 6,25 mg/mL e de EQ 1,56 ou 3,12 mg/mL, enquanto os valores de CMM foram de 6,25 mg/mL para EG e de 1,56, 3,12 ou 6,25 mg/mL para EQ. Os resultados de ICIF indicaram 15 associações sinérgicas e 4 associações aditivas dos extratos contra a cepa padrão e, dentre cepas clínicas, foram obtidos 15 resultados aditivos. A partir dos resultados de ICMF foram identificadas 6 associações sinérgicas e 1 associação aditiva contra a cepa padrão, além de 8 associações com efeito aditivo contra cepas clínicas. A partir dos resultados de testes em culturas planctônicas foi avaliada a ação antibiofilme sobre as cepas em que foram observadas reduções de viabilidade de 36,7 e 34% para o EG (50 e 25 mg/mL) e 51,3 e 51,4% para EQ (25 e 12,5 mg/mL) contra cepa padrão. As reduções em cepas clínicas variaram de 43 a 73% com EG e de 36 a 79% para EQ. As associações dos extratos promoveram reduções de viabilidade de 8 a 35% contra 5 das 7 cepas clínicas. Conclui-se que os extratos glicólicos de gengibre e quilaia apresentam ação antimicrobiana de forma isolada e combinados com efeito aditivo sobre a forma planctônica de cepas clínicas resistentes de P. aeruginosa. De forma isolada, os extratos apresentaram importante ação preventiva na formação dos biofilmes dessas cepas, podendo ser considerados potenciais fitoterápicos com aplicações terapêuticas para o combate das infecções por P. aeruginosa. (AU)

Plant extracts have demonstrated several positive health effects, including antimicrobial action, however, the clinical use of phytotherapy is still discreet, so that more studies on the beneficial effects of pharmacological synergism of extracts could contribute to its therapeutic application. The aim of this study was to evaluate the effects of glycolic extracts of ginger (EG) and quilaia (EQ) alone and in combination on 7 clinical strains of Pseudomonas aeruginosa and a standard strain in planktonic form and monotypic biofilms. For the antimicrobial analysis on planktonic culture, tests were performed to determine the Minimum Inhibitory Concentration (MIC) and Minimum Microbicidal Concentration (MMC) (CLSI, M07-A9) of the isolated extracts, in addition to the Fractional Inhibitory Concentration Index (FICI) and the Fractionated Microbicidal Concentration Index (FICM) for the combined extracts. Statistical analysis was performed using the ANOVA method and Tukey's test for data with normal distribution and Kruskall-Wallis with Dunn's Multiple Comparison Test for data without normal distribution (5% significance). For the standard strain, MIC were determined equal to 3.12 mg/mL and MMC equal to 6.25 mg/mL for both extracts. For clinical strains the MIC of EG were 3.12 or 6.25 mg/mL and 1.56 or 3.12 mg/mL of EQ, while the MMC values were 6.25 mg/mL for EG and 1.56, 3.12 or 6.25 mg/ml for EQ. The FICI results indicated 15 synergistic and 4 additive associations of the extracts against the standard strain and, among clinical strains, 15 additive results were obtained. From the FICM results, 6 synergistic and 1 additive association against the standard strain were identified, in addition to 8 associations with additive effect against clinical strains. Based on the results of tests on planktonic cultures, the antibiofilm action were evaluated on the strains in which viability reductions of 36 and 34% were observed for EG (50 and 25 mg/mL) and 51% were observed for EQ (25 and 12, 5 mg/mL) against the standard strain. Reductions in clinical strains ranged from 43 to 73% with EG and from 36 to 79% for EQ. Associations of extracts promoted viability reductions of 8 to 35% against 5 out of 7 clinical strains. It is concluded that the glycolic extracts of ginger and quilaia have antimicrobial action in isolation and combined with additive effect on the planktonic form of resistant clinical strains of P. aeruginosa. Isolated, the extracts showed an important preventive action in the formation of biofilms of these strains and may be considered potential herbal medicines with therapeutic applications to combat P. aeruginosa infections. (AU)