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1.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 56(4): 335-341, 2021 Apr 09.
Artigo em Chinês | MEDLINE | ID: mdl-33832034

RESUMO

Objective: To study the effect of various concentrations of Enterococcus faecalis (Ef) supernatants on human periodontal ligament cell (hPDLC) and the inflammatory response of hPDLC under static pressure. Methods: The method of methyl thiazolyl tetrazolium (MTT) was used to detect the effect of various concentrations of Ef supernatants on the proliferation of hPDLCs and the flow cytometry was used to detect the expression of Toll-like receptor 2 (TLR-2) on the surface of hPDLC after 24-hour-stimulation of Ef supernatant. Furthermore, the hPDLCs were divided into non inducing group without Ef supernatant and inducing group with 5% Ef supernatant, and hPDLCs in each group were loaded with 0, 49 and 196 Pa static pressures respectively. The expressions of tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) mRNA and protein were detected by reverse transcription-PCR (RT-PCR) and enzyme linked immunosorbent assay (ELISA) after 24 hours. Results: MTT results showed that the supernatant of Ef with concentration≥5% could significantly inhibit the proliferation activity of hPDLCs at 48 hours of cell culture (P<0.05). Flow cytometry showed that the positive cell rates of TLR-2 increased with increasing volume fractions of the Ef supernatants. The values were (2.12±0.07)%, (2.41±0.32)%, (2.65±0.27)%, (4.76±0.46)%, (9.91±0.92)% and (12.01±1.35)%, respectively. The differences were statistically significant when the concentrations≥5% (P<0.05). There were no significant differences in the expressions of IL-1ß and TNF-α mRNA between the non inducing group and the control group under the pressure of 49 Pa (P>0.05). However, there were significant differences in the expressions of IL-1ß and TNF-α mRNA between the non inducing group and the control group under the pressure of 196 Pa (P<0.05), while the expressions of IL-1ß and TNF-α in the inducing group were significantly lower than that in the control group under the pressures of 49 and 196 Pa (P<0.05). Compared with the control group, the mRNA expression was significantly increased (P<0.05). The result of ELISA was consistent with that of PCR. Conclusions: High concentration of Ef supernatant could inhibit the proliferation of hPDLC. Ef supernatant might promote the expression of TLR-2 on the surface of hPDLC. Excessive mechanical pressure induced the inflammatory response of hPDLC. The presence of inflammatory mediators could lead to the intolerance of hPDLC to pressures and small pressure could aggravate the inflammatory response.


Assuntos
Enterococcus faecalis , Ligamento Periodontal , Humanos , Interleucina-1beta , Lipopolissacarídeos , RNA Mensageiro , Fator de Necrose Tumoral alfa
2.
Nat Commun ; 12(1): 1523, 2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33750782

RESUMO

Enterococcus faecalis is a commensal and nosocomial pathogen, which is also ubiquitous in animals and insects, representing a classical generalist microorganism. Here, we study E. faecalis isolates ranging from the pre-antibiotic era in 1936 up to 2018, covering a large set of host species including wild birds, mammals, healthy humans, and hospitalised patients. We sequence the bacterial genomes using short- and long-read techniques, and identify multiple extant hospital-associated lineages, with last common ancestors dating back as far as the 19th century. We find a population cohesively connected through homologous recombination, a metabolic flexibility despite a small genome size, and a stable large core genome. Our findings indicate that the apparent hospital adaptations found in hospital-associated E. faecalis lineages likely predate the "modern hospital" era, suggesting selection in another niche, and underlining the generalist nature of this nosocomial pathogen.


Assuntos
Infecção Hospitalar/microbiologia , Enterococcus faecalis/genética , Enterococcus faecalis/metabolismo , Prednisolona/metabolismo , Prednisolona/farmacologia , Animais , Antibacterianos , Aves , Farmacorresistência Bacteriana/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Genes MDR/genética , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/microbiologia , Hospitais , Especificidade de Hospedeiro , Humanos , Filogenia , Fatores de Virulência , Sequenciamento Completo do Genoma
3.
Molecules ; 26(4)2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33670315

RESUMO

Arabian flora is a rich source of bioactive compounds. In this study, we investigated three aromatic plant species with the aim of finding valuable sources of antimicrobial agents against common pathogenic microorganisms. We focused especially on microorganisms, which cause outbreaks of infectious disease during mass gatherings and pilgrimages season in Saudi Arabia. The essential oils of three aromatic plant species were hydrodistilled from flowering aerial parts of Lavandula pubescens Decne. and Pulicaria incisa subsp. candolleana E.Gamal-Eldin, and from leaves, stems, ripe and unripe fruits of Juniperus procera Hochst. Ex Endl. They were subsequently analyzed by gas chromatography-mass spectrometry (GC-MS). The main constituents of L. pubescens were found to be carvacrol (55.7%), methyl carvacrol (13.4%), and ß-bisabolene (9.1%). P. incisa subsp. Candolleana essential oil was rich in linalool (33.0%), chrysanthenone (10.3%), eugenol (8.9%), and cis-chrysanthenol (8.0%); the major components of J. procera essential oil were α-pinene (31.3-62.5%) and δ-3-carene (7.3-30.3%). These essential oils were tested against thirteen American Type Culture Collection (ATCC) strains of Gram-positive and Gram-negative bacteria using the agar diffusion assay. The only effective essential oil was that of L. pubescens and the most sensitive strains were Acinetobacter baumannii, Salmonella typhimurium, Shigella sonnei, Enterococcus faecalis and Staphylococcus epidermidis. Carvacrol, the major constituent of L. pubescens, was tested on these strains and was compared with vancomycin, amikacin, and ciprofloxacin. The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) assays of L. pubescens essential oil and carvacrol revealed that Gram-negative strains were more susceptible than the Gram-positive ones.


Assuntos
Juniperus/química , Lavandula/química , Óleos Voláteis/química , Óleos Vegetais/química , Pulicaria/química , Antibacterianos/química , Antibacterianos/farmacologia , Cimenos/química , Cimenos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/farmacologia , Componentes Aéreos da Planta/química , Folhas de Planta/química , Óleos Vegetais/farmacologia , Arábia Saudita , Staphylococcus aureus/efeitos dos fármacos
4.
Medicine (Baltimore) ; 100(13): e25285, 2021 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-33787613

RESUMO

ABSTRACT: Surface treatment of medical devices may be a way of avoiding the need for replacement of these devices and the comorbidities associated with infection. The aim of this study was to evaluate whether pre- and postcontamination washing of 2 prostheses with different textures can decrease bacterial contamination.The following microorganisms were evaluated: Staphylococcus aureus, Staphylococcus epidermidis, Proteus mirabilis and Enterococcus faecalis. Silicone and expanded polytetrafluoroethylene vascular prostheses were used and divided into 3 groups: prostheses contaminated; prostheses contaminated and treated before contamination; and prostheses contaminated and treated after contamination. Treatments were performed with antibiotic solution, chlorhexidine and lidocaine. After one week of incubation, the prostheses were sown in culture medium, which was incubated for 48 hours. The area of colony formation was evaluated by fractal dimension, an image analysis tool.The antibiotic solution inhibited the growth of S epidermidis and chlorhexidine decrease in 53% the colonization density for S aureus in for both prostheses in the pre-washing. In postcontamination washing, the antibiotic solution inhibited the growth of all bacteria evaluated; there was a 60% decrease in the colonization density of S aureus and absence of colonization for E faecalis with chlorhexidine; and lidocaine inhibited the growth of S aureus in both prostheses.Antibiotic solution showed the highest efficiency in inhibiting bacterial growth, especially for S epidermidis, in both washings. Lidocaine was able to reduce colonization by S aureus in post-contamination washing, showing that it can be used as an alternative adjuvant treatment in these cases.


Assuntos
Prótese Vascular/microbiologia , Descontaminação/métodos , Desinfetantes/administração & dosagem , Infecções Relacionadas à Prótese/prevenção & controle , Antibacterianos/administração & dosagem , Contagem de Colônia Microbiana , Enterococcus faecalis/crescimento & desenvolvimento , Humanos , Lidocaína/administração & dosagem , Politetrafluoretileno , Desenho de Prótese , Infecções Relacionadas à Prótese/microbiologia , Proteus mirabilis/crescimento & desenvolvimento , Silicones , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus epidermidis/crescimento & desenvolvimento
5.
J Appl Oral Sci ; 29: e20200733, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33656065

RESUMO

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


Assuntos
Biofilmes , Enterococcus faecalis , Endopeptidase Clp , Humanos , Microscopia Confocal , Microscopia Eletrônica de Varredura , Peptídeo Hidrolases , Virulência
6.
Molecules ; 26(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573147

RESUMO

To determine the antibacterial effect of propolis nanoparticles (PNs) as an endodontic irrigant against Enterococcus faecalis biofilm inside the endodontic root canal system. Two-hundred-ten extracted human teeth were sectioned to obtain 6 mm of the middle third of the root. The root canal was enlarged to an internal diameter of 0.9 mm. The specimens were inoculated with E. faecalis for 21 days. Following this, specimens were randomly divided into seven groups, with 30 dentinal blocks in each group including: group I-saline; group II-propolis 100 µg/mL; group III-propolis 300 µg/mL; group IV-propolis nanoparticle 100 µg/mL; group V-propolis nanoparticle 300µg/mL; group VI-6% sodium hypochlorite; group VII-2% chlorhexidine. Dentin shavings were collected at 200 and 400 µm depths, and total numbers of CFUs were determined at the end of one, five, and ten minutes. The non-parametric Kruskal-Wallis and Mann-Whitney tests were used to compare the differences in reduction in CFUs between all groups, and probability values of p < 0.05 were set as the reference for statistically significant results. The antibacterial effect of PNs as an endodontic irrigant was also assessed against E. faecalis isolates from patients with failed root canal treatment. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were also performed after exposure to PNs. A Raman spectroscope, equipped with a Leica microscope and lenses with curve-fitting Raman software, was used for analysis. The molecular interactions between bioactive compounds of propolis (Pinocembrin, Kaempferol, and Quercetin) and the proteins Sortase A and ß-galactosidase were also understood by computational molecular docking studies. PN300 was significantly more effective in reducing CFUs compared to all other groups (p < 0.05) except 6% NaOCl and 2% CHX (p > 0.05) at all time intervals and both depths. At five minutes, 6% NaOCl and 2% CHX were the most effective in reducing CFUs (p < 0.05). However, no significant difference was found between PN300, 6% NaOCl, and 2% CHX at 10 min (p > 0.05). SEM images also showed the maximum reduction in E. faecalis with PN300, 6% NaOCl, and 2% CHX at five and ten minutes. CLSM images showed the number of dead cells in dentin were highest with PN300 compared to PN100 and saline. There was a reduction in the 484 cm-1 band and an increase in the 870 cm-1 band in the PN300 group. The detailed observations of the docking poses of bioactive compounds and their interactions with key residues of the binding site in all the three docking protocols revealed that the interactions were consistent with reasonable docking and IFD docking scores. PN300 was equally as effective as 6% NaOCl and 2% CHX in reducing the E. faecalis biofilms.


Assuntos
Antibacterianos/administração & dosagem , Enterococcus faecalis/efeitos dos fármacos , Nanopartículas/química , Própole/administração & dosagem , Adulto , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Cavidade Pulpar/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Dentina/microbiologia , Enterococcus faecalis/patogenicidade , Feminino , Humanos , Masculino , Microscopia Confocal , Simulação de Acoplamento Molecular , Própole/química
7.
BMJ Case Rep ; 14(2)2021 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558386

RESUMO

A 45-year-old man had recurrent presentations with pleuritic chest pain and shortness of breath. Four months prior, he had developed cauda equina syndrome from a spinal epidural abscess in the setting of intravenous drug use, complicated by lasting neurological deficits and a rectal prolapse. On his final presentation, blood cultures taken in the absence of antibiotics grew Enterococcus faecalis from multiple sets. A transoesophageal echocardiogram confirmed tricuspid valve endocarditis. He recovered well post-targeted long-term antibiotics. Endoscopy confirmed a chronic rectal prolapse with multiple ulcers and was hypothesised as the source of bacteraemia. He subsequently underwent perineal rectosigmoidectomy. This uncommon sequela of rectal prolapse highlights several issues, including the management of neurogenic bowel dysfunction following spinal cord injury and the importance of early prolapse recognition and management. Finally, appropriate collection of blood cultures and correct use of echocardiography are critical steps in investigating infective endocarditis.


Assuntos
Endocardite Bacteriana/diagnóstico , Enterococcus faecalis , Abscesso Epidural/complicações , Abscesso Epidural/microbiologia , Infecções por Bactérias Gram-Positivas/diagnóstico , Prolapso Retal/complicações , Prolapso Retal/microbiologia , Antibacterianos/uso terapêutico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Síndrome da Cauda Equina/etiologia , Doença Crônica , Colonoscopia , Diagnóstico Diferencial , Ecocardiografia Transesofagiana , Endocardite Bacteriana/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Abuso de Substâncias por Via Intravenosa/complicações
8.
Int J Oral Maxillofac Implants ; 36(1): 68-74, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33600525

RESUMO

PURPOSE: The aim of this study was to test in vitro the bacterial microleakage at the Morse taper implant-abutment connection with switched platform subjected to functional load and thermocycling. MATERIALS AND METHODS: A total of 48 Morse taper implant-abutment connections with switched platforms (12 implants per group) were used. The abutments were attached to implants and presented in four groups: group 1, control; group 2, subjected to thermocycling; group 3, subjected to cyclic compressive loading; and group 4, subjected to thermocycling and cyclic compressive loading. All groups were then inoculated in Eppendorf tubes including three types of bacterial suspensions: Enterococcus faecalis, Staphylococcus aureus, and Pseudomonas aeruginosa for 7 and 14 days to detect possibility of bacterial infiltration from outside to the internal chamber of the implant. RESULTS: Implants not exposed to cyclic loading and thermocycling (group 1) and those exposed to thermocycling (group 2) exhibited no infiltration of E faecalis, S aureus, and P aeruginosa from outside to the inner chamber of the implant, while infiltration of P aeruginosa was only observed in implants subjected to cyclic loading only (group 3) and those subjected to cyclic loading in conjunction with thermocycling (group 4). CONCLUSION: Microbial leakage at the implant-abutment connection is influenced by the applied load alone and in combination with thermocycling; however, E faecalis and S aureus did not leak at the implant-abutment connection even under these circumstances. Only P aeruginosa infiltrated inside the implant-abutment connection, which might be caused by its swarming motility.


Assuntos
Implantes Dentários , Infiltração Dentária , Dente Suporte , Projeto do Implante Dentário-Pivô/efeitos adversos , Implantes Dentários/efeitos adversos , Infiltração Dentária/etiologia , Enterococcus faecalis , Humanos , Teste de Materiais
9.
ACS Appl Mater Interfaces ; 13(7): 8082-8094, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570927

RESUMO

Antibiotic-resistant bacteria are a significant and growing threat to human health. Recently, two-dimensional (2D) nanomaterials have shown antimicrobial activity and have the potential to be used as new approaches to treating antibiotic resistant bacteria. In this Research Article, we exfoliate transition metal dichalcogenide (TMDC) nanosheets using synthetic single-stranded DNA (ssDNA) sequences, and demonstrate the broad-spectrum antibacterial activity of MoSe2 encapsulated by the T20 ssDNA sequence in eliminating several multidrug-resistant (MDR) bacteria. The MoSe2/T20 is able to eradicate Gram-positive Escherichia coli and Gram-positive Staphylococcus aureus at much lower concentrations than graphene-based nanomaterials. Eradication of MDR strains of methicillin-resistant S. aureus (MRSA), Enterococcus faecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae, and Acinetobacter baumannii are shown to occur at at 75 µg mL-1 concentration of MoSe2/T20, and E. coli at 150 µg mL-1. Molecular dynamics simulations show that the thymine bases in the T20 sequence lie flat on the MoSe2 surface and can, thus, form a very good conformal coating and allow the MoSe2 to act as a sharp nanoknife. Electron microscopy shows the MoSe2 nanosheets cutting through the cell membranes, resulting in significant cellular damage and the formation of interior voids. Further assays show the change in membrane potential and reactive oxygen species (ROS) formation as mechanisms of antimicrobial activity of MoSe2/T20. The cellular death pathways are also examined by mRNA expression. This work shows that biocompatible TMDCs, specifically MoSe2/T20, is a potent antimicrobial agent against MDR bacteria and has potential for clinical settings.


Assuntos
Antibacterianos/farmacologia , Calcogênios/farmacologia , DNA de Cadeia Simples/química , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Metais Pesados/farmacologia , Células A549 , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/química , Cápsulas/química , Cápsulas/farmacologia , Calcogênios/química , DNA de Cadeia Simples/síntese química , Enterococcus faecalis/efeitos dos fármacos , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Metais Pesados/química , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Pseudomonas aeruginosa/efeitos dos fármacos , Espécies Reativas de Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Propriedades de Superfície
10.
mBio ; 12(1)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33622720

RESUMO

Enterococcus faecalis differs from many other common human pathogens in its physiology and in its susceptibility to antimicrobial agents. Multiresistant E. faecalis strains owe their phenotypes to a combination of intrinsic and acquired antimicrobial resistance determinants. Acquired resistance is due to E. faecalis frequenting multicultural environments, its capacity to mate with different species, and the nullification of its own defense mechanisms in some lineages. Intrinsic resistance is a complex phenomenon that is intimately tied to the physiology of the species. In their recent study in mBio, Gilmore and colleagues (M. S. Gilmore, R. Salamzade, E. Selleck, N. Bryan, et al., mBio 11:e02962-20, 2020, https://doi.org/10.1128/mBio.02962-20) use functional genomics to explore the genetic underpinnings of E. faecalis physiology and antimicrobial resistance. While they do not come up with many definitive answers, their work points the way toward new and fruitful areas of investigation.


Assuntos
Antibacterianos , Enterococcus faecalis , Antibacterianos/farmacologia , Biologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Humanos , Testes de Sensibilidade Microbiana
11.
Mayo Clin Proc ; 96(1): 132-146, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33413809

RESUMO

OBJECTIVE: To investigate the rate of colorectal neoplasms (CRNs) in patients who have Enterococcus faecalis infective endocarditis (EFIE) with available colonoscopies and to assess whether this is associated with the identification of a focus the infection. PATIENTS AND METHODS: Retrospective analysis of data from a prospective multicenter study involving 35 centers who are members of the Grupo de Apoyo para el Manejo de la Endocarditis en España [Support Group for the Management of Infective Endocarditis in Spain] cohort. A specific set of queries regarding information on colonoscopy and histopathology of colorectal diseases was sent to each participating center. Four-hundred sixty-seven patients with EFIE were included from January 1, 2008, to December 31, 2017, from whom data on colonoscopy performance and results were available in 411 patients. RESULTS: One hundred forty-two (34.5%) patients had a colonoscopy close to the EFIE episode. The overall rate of colorectal diseases was 70.4% (100 of 142), whereas the prevalence of CRN (advanced adenomas and colorectal carcinoma) was 14.8% (21 of 142), with no significant differences between the group of EFIE of unknown focus and that with an identified focus. CONCLUSION: Our study adds to prior evidence suggesting a much higher rate of CRN among patients with EFIE than in the general population of the same age and sex. In addition, our findings suggest that this phenomenon might take place both in EFIE with an unknown and an identified source of infection.


Assuntos
Neoplasias Colorretais/etiologia , Endocardite Bacteriana/complicações , Enterococcus faecalis , Infecções por Bactérias Gram-Positivas/complicações , Idoso , Idoso de 80 Anos ou mais , Colonoscopia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/microbiologia , Endocardite Bacteriana/microbiologia , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco
12.
Monogr Oral Sci ; 29: 38-52, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33427232

RESUMO

When analyzing the activity of antimicrobial agents, it should be considered that microorganisms mainly occur in biofilms. Data obtained for planktonic bacteria cannot be transferred non-critically to biofilms. Biofilm models should consider both the relevant microorganisms and the conditions present in the environment. The selection of the model depends on the question to be answered. In dentistry, single species, multispecies, or microcosms originating from saliva or dental biofilm are used to culture biofilms. Microorganism selection depends on the focus of the study, for example caries biofilms mostly include Streptococcus mutans, an endodontic biofilm consists mostly of Enterococcus faecalis, and defined anaerobes are used in periodontal/peri-implant biofilms. In contrast to single-species biofilm models in medicine, where the lowest concentration of the antimicrobial that kills microorganisms is measured, the common analyzed variables are counts of colony-forming units or the percentage of dead bacteria determined by confocal laser scanning microscopy after applying a differentiating stain. All the models are helpful to evaluate new antimicrobial treatment options. Conclusions regarding the antimicrobial activity tendency of the therapeutics can be drawn. However, there are limitations of the model and ultimately a new therapy has to be proven in randomized controlled clinical trials.


Assuntos
Biofilmes , Cárie Dentária , Enterococcus faecalis , Humanos , Saliva , Streptococcus mutans
13.
Appl Environ Microbiol ; 87(7)2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33483312

RESUMO

Enterococcal plasmid-encoded bacteriolysin Bac41 is a selective antimicrobial system that is considered to provide a competitive advantage to Enterococcus faecalis cells that carry the Bac41-coding plasmid. The Bac41 effector consists of the secreted proteins BacL1 and BacA, which attack the cell wall of the target E. faecalis cell to induce bacteriolysis. Here, we demonstrated that galU, which encodes UTP-glucose-1-phosphate uridylyltransferase, is involved in susceptibility to the Bac41 system in E. faecalis Spontaneous mutants that developed resistance to the antimicrobial effects of BacL1 and BacA were revealed to carry a truncation deletion of the C-terminal amino acid (aa) region 288 to 298 of the translated GalU protein. This truncation resulted in the depletion of UDP-glucose, leading to a failure to utilize galactose and produce the enterococcal polysaccharide antigen (EPA), which is expressed abundantly on the cell surface of E. faecalis This cell surface composition defect that resulted from galU or EPA-specific genes caused an abnormal cell morphology, with impaired polarity during cell division and alterations of the limited localization of BacL1 Interestingly, these mutants had reduced susceptibility to beta-lactams besides Bac41, despite their increased susceptibility to other bacteriostatic antimicrobial agents and chemical detergents. These data suggest that a complex mechanism of action underlies lytic killing, as exogenous bacteriolysis induced by lytic bacteriocins or beta-lactams requires an intact cell physiology in E. faecalis IMPORTANCE Cell wall-associated polysaccharides of bacteria are involved in various physiological characteristics. Recent studies demonstrated that the cell wall-associated polysaccharide of Enterococcus faecalis is required for susceptibility to bactericidal antibiotic agents. Here, we demonstrated that a galU mutation resulted in resistance to the enterococcal lytic bacteriocin Bac41. The galU homologue is reported to be essential for the biosynthesis of species-specific cell wall-associated polysaccharides in other Firmicutes In E. faecalis, the galU mutant lost the E. faecalis-specific cell wall-associated polysaccharide EPA (enterococcal polysaccharide antigen). The mutant also displayed reduced susceptibility to antibacterial agents and an abnormal cell morphology. We demonstrated here that galU was essential for EPA biosynthesis in E. faecalis, and EPA production might underlie susceptibility to lytic bacteriocin and antibiotic agents by undefined mechanisms.


Assuntos
Proteínas de Bactérias/genética , Bacteriocinas/metabolismo , Enterococcus faecalis/genética , Polissacarídeos/química , UTP-Glucose-1-Fosfato Uridililtransferase/genética , Proteínas de Bactérias/metabolismo , Bacteriólise , Parede Celular/metabolismo , Enterococcus faecalis/enzimologia , UTP-Glucose-1-Fosfato Uridililtransferase/metabolismo
14.
BMJ Case Rep ; 14(1)2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504526

RESUMO

To report the clinical course and management of interface keratitis due to Enterococcus faecalis after Descemet membrane endothelial keratoplasty (DMEK). A 64-year-old man underwent DMEK, with unevenful immediate postoperative course, with a visual recovery of 20/30 at 2 weeks. At 3 months of clinical visit, interface keratitis was noted. DMEK graft removal with stromal bed scrapings was performed. A diagnosis of E. faecalis interface keratitis was made. The patient responded favourably to antibiotic susceptibility-guided intensive treatment with vancomycin 5% with complete resolution of infection. After 2 months of graft removal, Descemet stripping endothelial keratoplasty (DSEK) was performed. The corneal clarity was restored and the best corrected visual acuity was 20/40 at last follow-up of 1 year. E. faecalis should be kept as a differential in delayed onset interface keratitis after DMEK. After microbiological cure with antibiotic therapy, visual rehabilitation with DSEK restores corneal clarity and results in favourable visual outcome.


Assuntos
Transplante de Córnea , Enterococcus faecalis/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Ceratite/diagnóstico , Infecção da Ferida Cirúrgica/diagnóstico , Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Ceratite/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Infecção da Ferida Cirúrgica/tratamento farmacológico , Tomografia de Coerência Óptica , Vancomicina/uso terapêutico
15.
Arch Virol ; 166(2): 593-599, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33392817

RESUMO

Enterococcus phage Nonaheksakonda was isolated from wastewater, using a vancomycin-resistant strain of the opportunistic pathogen Enterococcus faecalis (VRE) as a host. Nonaheksakonda is a lytic phage infecting E. faecalis V583 and clinical isolates with at least four different multi-locus sequence types (MLSTs). The genome is a 41.9-kb double-stranded DNA molecule (34.6% GC) with 74 coding sequences. Comparative analysis revealed only one close relative, Enterococcus phage heks. All other phages had low protein similarity and shared less than 54% nucleotide sequence identity with phage Nonaheksakonda. The most similar phages were all classified and unclassified efquatroviruses. We propose that the phages Nonaheksakonda and heks represent a novel genus within the family Siphoviridae, order Caudovirales, for which we propose the name "Nonaheksakondavirus".


Assuntos
Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Enterococcus faecalis/virologia , Siphoviridae/genética , Siphoviridae/isolamento & purificação , DNA/genética , Genoma Viral/genética
16.
ACS Nano ; 15(1): 1167-1178, 2021 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-33498106

RESUMO

Existing methods for RNA diagnostics, such as reverse transcription PCR (RT-PCR), mainly rely on nucleic acid amplification (NAA) and RT processes, which are known to introduce substantial issues, including amplification bias, cross-contamination, and sample loss. To address these problems, we introduce a confinement effect-inspired Cas13a assay for single-molecule RNA diagnostics, eliminating the need for NAA and RT. This assay involves confining the RNA-triggered Cas13a catalysis system in cell-like-sized reactors to enhance local concentrations of target and reporter simultaneously, via droplet microfluidics. It achieves >10 000-fold enhancement in sensitivity when compared to the bulk Cas13a assay and enables absolute digital single-molecule RNA quantitation. We experimentally demonstrate its broad applicability for precisely counting microRNAs, 16S rRNAs, and SARS-CoV-2 RNA from synthetic sequences to clinical samples with excellent accuracy. Notably, this direct RNA diagnostic technology enables detecting a wide range of RNA molecules at the single-molecule level. Moreover, its simplicity, universality, and excellent quantification capability might render it to be a dominant rival to RT-qPCR.


Assuntos
Sistemas CRISPR-Cas , Microfluídica , RNA/análise , Linhagem Celular Tumoral , Enterococcus faecalis , Escherichia coli , Humanos , Klebsiella pneumoniae , Células MCF-7 , MicroRNAs/análise , Pseudomonas aeruginosa , RNA Ribossômico 16S/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Staphylococcus aureus
17.
J Endod ; 47(3): 451-457, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33359252

RESUMO

INTRODUCTION: The purpose of this study was to examine the colonization and tubular invasion of Enterococcus faecalis in minimally altered canal walls. We hypothesized that age, axial directions (buccolingual or mesiodistal), regions (apical, midroot, or cervical), and disinfection treatment (sodium hypochlorite or autoclave) would impact bacterial colonization and invasion patterns. METHODS: Single roots of extracted teeth from 2 age groups (≤30 years old and ≥60 years old) were challenged with bacteria for 2 weeks. Colonization on the canal walls in 3 regions was evaluated with scanning electron microscopy. The prevalence of tubular invasion in the axial directions in 3 regions was examined with confocal laser scanning microscopy. The data were analyzed using the GLIMMIX procedure in SAS software (SAS Institute Inc, Cary, NC) with a Tukey adjustment for comparisons. RESULTS: Bacteria successfully colonized and invaded tubules in 2 weeks. The apical region in the ≥60-year age group was the least infected. A significantly higher invasion prevalence in a buccolingual (B/L) than a mesiodistal (M/D) direction was detected in both age groups and in all 3 regions. The ≤30-year age group had a significantly higher prevalence of tubular invasion than the ≥60-year age group in the B/L and M/D direction, respectively. Sodium hypochlorite treatment significantly impacted bacterial colonization and invasion in more calcified areas. CONCLUSIONS: Our data support a more conservative enlargement of the apical region of older teeth. An emphasis in a B/L direction rather than an M/D direction is recommended for debridement.


Assuntos
Enterococcus faecalis , Irrigantes do Canal Radicular , Biofilmes , Cavidade Pulpar , Dentina , Microscopia Confocal , Hipoclorito de Sódio/farmacologia
18.
Braz. dent. sci ; 24(1): 1-7, 2021. tab, ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1145548

RESUMO

Though aloe vera extract, green tea extract and coriander oil are proven antimicrobial agents, very little information is available regarding its effects on oral bacteria, Streptococcus mutans, which is responsible for initiating caries and Enterococcus faecalis, responsible for failure of root canal treatment. Objective: To find the antimicrobial activity of aloe vera extract, black tea extract and coriander oil against S. mutans and E. faecalis. Materials and Methods: The agar well diffusion method was used to determine the antibacterial activity of Aloe vera extract, black tea extract and coriander oil. Different concentration of prepared plant extracts and coriander seed oil (50 & 100 µl) was incorporated into the wells and the plates containing S. mutans and E. faecalis were incubated at 37 °C for 24 h. The antibiotic (amoxicillin 30 µl) was used as positive control. Zone Of Inhibition (ZOI) was recorded in each plate. Results: For S. mutans, the maximum ZOI was created by coriander oil with a diameter of 25.00±0.58 mm at 50 µl and for E. faecalis, maximum ZOI was created by aloe vera extract 16.00±0.58 mm at 100 µl concentration which were far better than the control: amoxicillin 30 µl concentration. Conclusion: The extracts of Aloe vera, black tea and coriander oil, showed significant activity against the investigated microbial strains, Streptococcus mutans and Enterococcus faecalis which further helps in the development of new topical agents that help in reducing the numbers of these organisms present in the oral cavity. (AU)


Embora o extrato de aloe vera, extrato de chá verde e óleo de coentro sejam agentes antimicrobianos comprovados, há pouca informação disponível sobre seus efeitos nas bactérias orais, Streptococcus mutans, que é responsável por iniciar cáries e Enterococcus faecalis, responsável pela falha do tratamento de canal radicular. Objetivo: Avaliar a atividade antimicrobiana do extrato de aloe vera, extrato de chá preto e óleo de coentro contra S. mutans e E. faecalis. Materiais e Métodos: O método de difusão em agar foi usado para determinar a atividade antibacteriana do extrato de Aloe vera, extrato de chá preto e óleo de coentro. Diferentes concentrações dos extratos de plantas e óleo de semente de coentro (50 e 100 µl) foram preparados e colocados nos poços e nas placas contendo S. mutans e E. faecalis e foram incubadas a 37°C por 24 h. O antibiótico (amoxicilina 30 µl) foi utilizado como controle positivo. A zona de inibição (ZOI) foi registrada em cada placa. Resultados: Para S. mutans, a ZOI máxima foi obtida com o óleo de coentro com um diâmetro de 25,00 ± 0,58 mm a 50 µl e para E. faecalis, a ZOI máxima foi obtiada pelo extrato de aloe vera 16,00 ± 0,58 mm na concentração de 100 µl, as quais foram melhores do que o controle: concentração de 30 µl de amoxicilina. Conclusão: Os extratos de Aloe vera, chá preto e óleo de coentro apresentaram atividade significativa contra as cepas microbianas investigadas, Streptococcus mutans e Enterococcus faecalis auxiliando no desenvolvimento de novos agentes tópicos visando a redução do número desses organismos presentes no cavidade oral. (AU)


Assuntos
Streptococcus mutans , Chá , Enterococcus faecalis , Aloe , Microbiota
19.
PLoS One ; 15(12): e0240773, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33378402

RESUMO

Infectious diseases are a threat to elderly individuals, whose immune systems weaken with age. Among the various infectious diseases, Clostridium difficile infection is associated with a high rate of mortality in elderly individuals and is a serious health problem worldwide, owing to the increasing infection rates. Probiotic use has been proposed as an effective countermeasure for C. difficile infection. The aim of this study was to evaluate the effects of heat-killed Enterococcus faecalis T-110 on intestinal immunity, intestinal flora, and intestinal infections, especially C. difficile infections, in naturally ageing animals, for extrapolating the results to elderly human subjects. Twenty female hamsters were randomly distributed into two groups. Group 1 was fed a basal diet and group 2 was fed a basal diet supplemented with heat-killed E. faecalis for 7 days. Heat-killed E. faecalis T-110 improved the gut immunity and microflora, especially Clostridium perfringens and C. difficile, in naturally aged hamsters. Therefore, heat-killed E. faecalis T-110 use may be a countermeasure against age-related immune dysfunction and intestinal infections, especially C. difficile infection, in elderly humans. However, further investigation in this regard is needed in humans.


Assuntos
Envelhecimento/imunologia , Infecções por Clostridium/prevenção & controle , Diarreia/prevenção & controle , Enterococcus faecalis/imunologia , Probióticos/administração & dosagem , Fatores Etários , Idoso , Animais , /isolamento & purificação , Infecções por Clostridium/imunologia , Infecções por Clostridium/microbiologia , Clostridium perfringens/imunologia , Clostridium perfringens/isolamento & purificação , Cricetinae , Diarreia/imunologia , Diarreia/microbiologia , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/imunologia , Temperatura Alta , Humanos , Tolerância Imunológica/fisiologia , Imunidade nas Mucosas , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia
20.
Braz Dent J ; 31(6): 611-616, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33237232

RESUMO

The aim of this study was to evaluate the antibacterial potential of a calcium silicate-based sealer (Bio-C Sealer, Angelus) against common bacteria in primary and secondary endodontic infections. Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Streptococcus mutans were exposed to fresh Bio-C Sealer for 24 h by the agar diffusion method (n=5). Additionally, the antibacterial activity was investigated against E. faecalis and S. mutans biofilms (48 h old) grown in discs with 4 mm in diameter and 2 mm in height. (n=3) of set discs of Bio-C Sealer (Angelus), EndoFill (Dentsply-Mallefer), Sealer 26 (Dentsply), AH Plus (Dentsply), Sealapex (Sybron-Endo) and EndoSequence BC Sealer (Brasseler). The antibacterial activity was evaluated by colony forming unity (CFU) counting using ImageJ software. Data were compared by one-way ANOVA followed by Holm-Sidak test (a=5%). Fresh Bio-C Sealer exhibited antimicrobial activity against all bacteria evaluated by agar diffusion method, except for S. mutans. Set discs of all endodontic sealers tested showed similar CFU values for E. faecalis (p>0.05). S. mutans in biofilms showed higher susceptibility to EndoFill compared with the other sealers (p<0.05). In conclusion, the results indicate that fresh Bio-C Sealer does not inhibit S. mutans growth, but exhibits antibacterial activity against E. faecalis, S. aureus, P. aeruginosa and E. coli. After setting, the Bio-C Sealer exhibits an antimicrobial potential comparable to that of the other sealers evaluated in E. faecalis biofilm, but lower than that of EndoFill for S. mutans biofilm.


Assuntos
Resinas Epóxi , Materiais Restauradores do Canal Radicular , Antibacterianos/farmacologia , Compostos de Cálcio , Enterococcus faecalis , Escherichia coli , Teste de Materiais , Materiais Restauradores do Canal Radicular/farmacologia , Silicatos/farmacologia , Staphylococcus aureus
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