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1.
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
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.
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
4.
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
5.
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
6.
Niger J Clin Pract ; 23(9): 1188-1193, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32913155

RESUMO

Aims: The aim of this study was to investigate the antimicrobial effect of Erbium, chromium-doped yttrium, scandium, gallium, and garnet (Er,Cr:YSGG) laser with and without NaOCl solution. A total of 81 extracted human mandibular premolar teeth were used. Materials and Methods: After root canal preparation and sterilization, the samples were inoculated with E. faecalis for 24 hours. The specimens were divided into 4 experimental groups. Group 1 (n = 25) was irradiated with 2 W laser, group 2 (n = 25) was irradiated with 0.75 W laser in combination with 2.5% NaOCl, group 3 (n = 25) was irrigated with 5% NaOCl and group 4 (n = 6) was not treated. Statistical analysis was performed by using Wilcoxon Signed Ranks, Mann-Whitney U and Kruskal-Wallis H tests. Results: The combination of 0.75 W laser with 2.5% NaOCl regime was found to be just as effective at inhibiting the growth of E. faecalis and sterilization of all root canals as 5% NaOCl irrigation (P > 0.001). The 2 W laser had significant bactericidal effect in infected root canals however it did not eradicate all bacteria. The SEM observations were in accordance with the microbiologic findings. Conclusions: Within the limitations of this laboratory study, NaOCl irrigation improved the antimicrobial effect of Er,Cr:YSGG laser irradiation. When the toxic effects of high percentage of NaOCl was considered, the combination of low-powered laser and low concentration of NaOCl can be used as an effective disinfection method in root canal treatment.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Cavidade Pulpar/microbiologia , Enterococcus faecalis/efeitos dos fármacos , Lasers de Estado Sólido/uso terapêutico , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Cromo , Érbio , Gálio , Humanos , Preparo de Canal Radicular , Tratamento do Canal Radicular/métodos , Escândio , Ítrio
7.
PLoS Biol ; 18(8): e3000814, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32797039

RESUMO

Plasmid-mediated horizontal gene transfer of antibiotic resistance and virulence in pathogenic bacteria underlies a major public health issue. Understanding how, in the absence of antibiotic-mediated selection, plasmid-bearing cells avoid being outnumbered by plasmid-free cells is key to developing counterstrategies. Here, we quantified the induction of the plasmidial sex pheromone pathway of Enterococcus faecalis to show that the integration of the stimulatory (mate-sensing) and inhibitory (self-sensing) signaling modules from the pCF10 conjugative plasmid provides a precise measure of the recipient-to-donor ratio, agnostic to variations in population size. Such ratiometric control of conjugation favors vertical plasmid transfer under low mating likelihood and allows activation of conjugation functions only under high mating likelihood. We further show that this strategy constitutes a cost-effective investment into mating effort because overstimulation produces unproductive self-aggregation and growth rate reduction. A mathematical model suggests that ratiometric control of conjugation increases plasmid fitness and predicts a robust long-term, stable coexistence of donors and recipients. Our results demonstrate how population-level parameters can control transfer of antibiotic resistance in bacteria, opening the door for biotic control strategies.


Assuntos
Proteínas de Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Enterococcus faecalis/genética , Transferência Genética Horizontal , Feromônios/genética , Percepção de Quorum/efeitos dos fármacos , Antibacterianos/farmacologia , Carga Bacteriana , Proteínas de Bactérias/metabolismo , Conjugação Genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Enterococcus faecalis/metabolismo , Expressão Gênica , Aptidão Genética , Modelos Estatísticos , Feromônios/biossíntese , Plasmídeos/química , Plasmídeos/metabolismo , Percepção de Quorum/genética , Virulência
8.
PLoS One ; 15(8): e0237011, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32745091

RESUMO

Enterococcus faecalis infective endocarditis (EFIE) is a severe disease of increasing incidence. The objective was to analyze whether the outcome of patients with native valve EFIE (NVEFIE) treated with a short course of ampicillin plus ceftriaxone (4wAC) was similar to patients treated according to international guidelines (6wAC). Between January 2008 and June 2018, 1,978 consecutive patients with definite native valve IE were prospectively included in a national registry. Outcomes of patients with NVEFIE treated with 4wAC were compared to those of patients who received 6wAC. Three hundred and twenty-two patients (16.3%) had NVEFIE. One hundred and eighty-three (56.8%) received AC. Thirty-nine patients (21.3%) were treated with 4wAC for four weeks and 70 patients (38.3%) with 6wAC. There were no differences in age or comorbidity. Patients treated 6wAC presented a longer duration of symptoms before diagnosis (21 days, IQR 7-60 days vs. 7 days, IQR 1-22 days; p = 0.002). Six patients presented perivalvular abscess and all of these received 6wAC. Surgery was performed on 14 patients (35.9%) 4wAC and 34 patients (48.6%) 6wAC (p = 0.201). In-hospital mortality, one-year mortality and relapses among 4wAC and 6wAC patients were 10.3% vs. 11.4% (p = 0.851); 17.9% vs. 21.4% (p = 0.682) and 5.1% vs. 4.3% (p = 0.833), respectively. In conclusion, a four-week course of AC may be considered as an alternative regimen in NVEFIE, notably in patients with shorter duration of symptoms and those without perivalvular abscess. These results support the performance of a randomized clinical trial to evaluate the efficacy of this short regimen.


Assuntos
Ampicilina/uso terapêutico , Ceftriaxona/uso terapêutico , Endocardite Bacteriana/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Estudos de Coortes , Quimioterapia Combinada , Endocardite/tratamento farmacológico , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/patogenicidade , Feminino , Gentamicinas/uso terapêutico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Masculino , Estudos Prospectivos , Fatores de Tempo
9.
AAPS PharmSciTech ; 21(7): 246, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32856115

RESUMO

Enterococcus faecalis infections represent a health concern, mainly in oral diseases, in which treatments with chlorhexidine solution (0.2%) are often used; however, it presents high toxicity degree and several side effects. Based on this, the use of natural products as an alternative to treatment has been explored. Nonetheless, plant extracts have poor organoleptic characteristics that impair theirs in natura use. Therefore, this work aimed to evaluate the analytical profile, biological activity, and cytotoxicity in vitro of S. brasiliensis-loaded chitosan microparticles (CMSb) produced using different aspersion flow rates. The analytical fingerprint was obtained by FTIR and NIR spectra. Principal components analysis (PCA) was used to verify the similarity between the samples. The crystallinity degree was evaluated by X-ray diffraction (XRD). Phytochemical screening (PS) was performed to quantify phytocompounds. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC). Antibiofilm activity and bactericidal kinetics against E. faecalis (ATCC 29212 and MB 146-clinical isolated) were also assessed. The hemolytic potential was performed to evaluate the cytotoxicity. Data provided by FTIR, NIR, and PCA analyses revealed chemical similarity between all CMSb. Furthermore, the results from XRD analysis showed that the obtained CMSb present amorphous characteristic. Tannins and polyphenols were accurately quantified by the PS, but methodology limitations did not allow the flavonoid quantification. The low hemolytic potential assay indicates that all samples are safe. Antimicrobial assays revealed that CMSb were able to inhibit not only the E. faecalis ATCC growth but also the biofilm formation. Only one CMSb sample was able to inhibit the clinical strain. These results highlighted the CMSb antimicrobial potential and revealed this system as a promising product to treat infections caused by E. faecalis.


Assuntos
Anacardiaceae , Anti-Infecciosos/administração & dosagem , Quitosana/administração & dosagem , Enterococcus faecalis/efeitos dos fármacos , Microesferas , Extratos Vegetais/administração & dosagem , Administração Oral , Anti-Infecciosos/isolamento & purificação , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Humanos , Testes de Sensibilidade Microbiana/métodos , Tamanho da Partícula , Casca de Planta , Extratos Vegetais/isolamento & purificação
10.
Acta Odontol Latinoam ; 33(1): 45-49, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32621599

RESUMO

The gutta-percha cones used in endodontic treatment are produced in aseptic conditions and their composition includes zinc oxide, which is responsible for antibacterial activity. However, there is the possibility of microbial contamination by manipulation, aerosol or during storage. Although several chemical agents have been tested for their decontamination, there is no consensus on the best disinfection protocol to be used. The aim of this study was to evaluate the decontamination of gutta-percha cones contaminated with the bacteria Enterococcus faecalis, by using chlorhexidine digluconate (CHX) and sodium hypochlorite (NaClO) at different concentrations for short exposure times. For this purpose, gutta-percha cones (size 40) were selected at random from a sealed box and immersed for 1 min in a microbial suspension. Then they were immersed in specific Petri dishes for different groups containing: CHX 2%, NaClO 1% or NaClO 2.5% for 30 s or 1 min, and subsequently placed in tubes containing BHI broth. After incubating the tubes for 48 h, it was observed that 1% and 2.5% NaClO and 2% CHX were effective for decontaminating the cones at those exposure time intervals. Microbial growth was detected in one of the replicates of the group with CHX applied for 30 s. To prevent the possibility of failures at this stage, the exposure time of gutta-percha cones to the decontaminating agent should not be reduced.


Assuntos
Clorexidina/análogos & derivados , Descontaminação/métodos , Desinfetantes de Equipamento Odontológico/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Guta-Percha , Irrigantes do Canal Radicular/farmacologia , Hipoclorito de Sódio/farmacologia , Esterilização/métodos , Anti-Infecciosos Locais , Clorexidina/farmacologia , Desinfetantes de Equipamento Odontológico/administração & dosagem , Enterococcus faecalis/isolamento & purificação , Contaminação de Equipamentos/prevenção & controle , Humanos , Materiais Restauradores do Canal Radicular , Irrigantes do Canal Radicular/administração & dosagem , Hipoclorito de Sódio/administração & dosagem
11.
Artigo em Inglês | MEDLINE | ID: mdl-32679828

RESUMO

Sodium hypochlorite (NaOCl), an effective endodontic irrigant against Enterococcus faecalis (EF), is harmful to periapical tissues. Natural pineapple-orange eco-enzymes (M-EE) and papaya eco-enzyme (P-EE) could be potential alternatives. This study aimed to assess the antimicrobial efficacy of M-EE and P-EE at different concentrations and fermentation periods against EF, compared to 2.5% NaOCl. Fermented M-EE and P-EE (3 and 6 months) at various concentrations were mixed with EF in a 96-well plate incubated for 24 h anaerobically. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of M-EE and P-EE were determined via EF growth observation. EF inhibition was quantitatively measured and compared between different irrigants using the one-way analysis of variance (ANOVA), and different fermentation periods using the independent-samples T-test. M-EE and P-EE showed MIC at 50% and MBC at 100% concentrations. There was no significant difference in antimicrobial effect when comparing M-EE and P-EE at 50% and 100% to 2.5% NaOCl. P-EE at 6 months fermentation exhibited higher EF inhibition compared to 3 months at concentrations of 25% (p = 0.017) and 0.78% (p = 0.009). The antimicrobial properties of M-EE and P-EE, at both 100% and 50% concentrations, are comparable to 2.5% NaOCl. They could therefore be potential alternative endodontic irrigants, but further studies are required.


Assuntos
Anti-Infecciosos/farmacologia , Enterococcus faecalis , Frutas/química , Animais , Enterococcus faecalis/efeitos dos fármacos , Humanos , Hipoclorito de Sódio/efeitos adversos , Hipoclorito de Sódio/farmacologia
12.
Int J Nanomedicine ; 15: 3921-3936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32581537

RESUMO

Background: Mesoporous calcium-silicate nanoparticles (MCSNs) have good prospects in the medical field due to their great physicochemical characteristics, antibacterial activity and drug delivery capacity. This study was to analyze the antibiofilm activity and mechanisms of silver (Ag) and zinc (Zn) incorporated MCSNs (Ag/Zn-MCSNs) with different percentages of Ag and Zn. Methods: Ag/Zn(1:9, molar ratio)-MCSNs and Ag/Zn(9:1, molar ratio)-MCSNs were prepared and characterized. Endocytosis of nanoparticles by Enterococcus faecalis (E. faecalis) treated with Ag/Zn-MCSNs was observed using TEM to explore the antibacterial mechanisms. The antibiofilm activity of Ag/Zn-MCSNs with different ratios of Ag and Zn was tested by E. faecalis biofilm model in human roots. The human roots pretreated by different Ag/Zn-MCSNs were cultured with E. faecalis. Then, SEM and CLSM were used to observe the survival of E. faecalis on the root canal wall. Cytotoxicity of the nanoparticles was tested by CCK8 kits. Results: The Ag/Zn-MCSNs release Ag+ and destroy the cell membranes to kill bacteria. The MCSNs containing Ag showed antibacterial activity against E. faecalis biofilms in different degrees, and they can adhere to dentin surfaces to get a continuous antibacterial effect. However, MTA, MCSNs and Zn-MCSNs could not disrupt the bacterial biofilms obviously. MCSNs, Ag/Zn(1:1, molar ratio)-MCSNs and Ag/Zn(1:9)-MCSNs showed no obvious cytotoxicity, while Ag-MCSNs and Ag/Zn(9:1)-MCSNs showed cytotoxicity. Zn-MCSNs can slightly promote cell proliferation. Conclusion: Ag/Zn-MCSNs have good antibiofilm activity. They might achieve an appropriate balance between the antibacterial activity and cytotoxicity by adjusting the ratio of Ag and Zn. Ag/Zn-MCSNs are expected to be a new type of root canal disinfectant or sealer for root canal treatment.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Nanopartículas/química , Prata/química , Zinco/química , Animais , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Compostos de Cálcio/química , Cavidade Pulpar/microbiologia , Dentina/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Humanos , Camundongos , Osteoblastos/efeitos dos fármacos , Porosidade , Silicatos/química , Prata/farmacologia , Zinco/farmacologia
13.
An Acad Bras Cienc ; 92(2): e20190615, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32556053

RESUMO

Hedychium coronarium J. Koening, belonging to Zingiberaceae family, is a perennial herb with fleshly aromatic rhizomes. There are no information about the antiplatelet properties of essential oils (EOs) from rhizomes (HCR) and leaves (HCL) of this herb, additionally, there are reports about the antibacterial activity of the Zingiberaceae species, however, no studies have been carried out in the Colombian Amazon Region. The EOs were characterized by GC-MS, the antiaggregant activity was assessed by ADP and Collagen as platelet agonist and the antibacterial activity against E. faecalis and S. aureus were evidenced by the determination of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). A high content of oxygenated monoterpenes were found in HCL essential oil (EO) and 20 compounds were identified in HCR EO. The HCL EO showed antiaggregant activity when collagen was used and HCR EO showed a concentration-dependent activity against ADP and collagen, meanwhile only the HCR EO showed antibacterial activity against E. faecalis and S. aureus.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Óleos Voláteis/farmacologia , Inibidores da Agregação de Plaquetas/farmacologia , Rizoma/química , Staphylococcus aureus/efeitos dos fármacos , Zingiberaceae/química , Antibacterianos/isolamento & purificação , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Folhas de Planta/química , Inibidores da Agregação de Plaquetas/isolamento & purificação , Rizoma/classificação , Zingiberaceae/classificação
14.
BMC Infect Dis ; 20(1): 356, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32517758

RESUMO

BACKGROUND: Vancomycin-resistant Enterococcus spp. (VRE) have spread all over the world. The present study aims to investigate the species distribution, specimen type and susceptibilities of Enterococcal species collected from Nanjing Drum Tower Hospital from 2013 to 2018. Additionally, distribution of VRE and prevalence of van gene among VRE isolates were also analyzed. METHODS: The susceptibilities of 3913 Enterococcus isolates were retrospectively investigated. Among these strains, 60 VRE strains were further anazlyed in this study. The minimum inhibitory concentrations (MICs) of the VRE strains towards vancomycin, teicoplanin and linezolid were determined by E-test. Polymerase chain reaction (PCR) and DNA sequencing were used to investigate the prevalence of van genes among VRE. Furthermore, the sequence types (STs) of VRE strains were explored by multi-locus sequence typing (MLST). RESULTS: Among the 3913 enterococci isolates, Enterococcus faecalis (n = 1870, 47.8%) and Enterococcus faecium (1738, 44.4%) were the main isolates. These Enterococcus strains were mainly isolated from urine (n = 1673, 42.8%), followed by secretions (n = 583, 14.9%) and ascites (n = 554, 14.2%). VRE displayed a decreasing trend year by year. Molecular analysis revealed that 49 out of 60 VRE isolates carried vanA gene, 10 carried vanM, and 1 carried both vanA and vanM genes. Sixteen distinct STs were identified among the 58 VREM, with ST78 (n = 16), ST192 (n = 8) and ST570 (n = 7) being the most dominant ones. CONCLUSIONS: E. faecalis and E. faecium were the major enterococci strains which are the main pathogens of urinary traction infections; vanA and vanM were the main determinants conferring resistance to vancomycin; ST78, ST192 and ST570 were the leading STs of VREM which displayed a decreasing trend of prevalence year by year.


Assuntos
Enterococcus/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina/isolamento & purificação , Antibacterianos/farmacologia , China , DNA Bacteriano/metabolismo , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Estudos Retrospectivos , Centros de Atenção Terciária , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética
15.
Lett Appl Microbiol ; 71(1): 39-45, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32390273

RESUMO

Filter feeding is a biotic process that brings waterborne bacteria in close contact with each other and may thus support the horizontal transfer of their antimicrobial resistance genes. This laboratory study investigated whether the freshwater sponge Ephydatia fluviatilis supported the transfer of vancomycin resistance between two Enterococcus faecalis strains that we previously demonstrated to exhibit pheromone responsive plasmid conjugation. Microcosm experiments exposed live and dead colonies of laboratory-grown sponges to a vancomycin-resistant donor strain and a rifampicin-resistant recipient strain of Ent. faecalis. Enterococci with both resistance phenotypes were detected on double selection plates. In comparison to controls, abundance of these presumed transconjugants increased significantly in water from sponge microcosms. Homogenized suspensions of sponge cells also yielded presumed transconjugants; however, there was no significant difference between samples from live or dead sponges. Fluorescent in situ hybridization analysis of the sponge cell matrix using species-specific probes revealed the presence of enterococci clusters with cells adjacent to each other. The results demonstrated that sponge colonies can support the horizontal transfer of antimicrobial resistance although the mechanism underlying this process, such as binding of the bacteria to the sponge collagen matrix, has yet to be fully elucidated.


Assuntos
Antibacterianos/farmacologia , Conjugação Genética/genética , Farmacorresistência Bacteriana/genética , Enterococcus faecalis/genética , Poríferos/microbiologia , Resistência a Vancomicina/genética , Animais , Enterococcus faecalis/efeitos dos fármacos , Água Doce , Hibridização in Situ Fluorescente , Feromônios/farmacologia , Plasmídeos/genética , Vancomicina/farmacologia
16.
Poult Sci ; 99(5): 2675-2683, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32359604

RESUMO

Enterococcus faecalis (E. faecalis) has rapidly acquired resistance to multiple antimicrobials, and the antimicrobial resistance of E. faecalis from broiler breeders has been implicated in its vertical transmission to their offspring. The objective of this study was to investigate the antimicrobial resistance and genetic diversity of commensal E. faecalis isolated from the broiler breeder farms. Among a total of 229 E. faecalis isolates from 9 broiler breeder farms, the highest resistance rate was observed in tetracycline (78.2%), followed by doxycycline (58.1%) and erythromycin (43.7%), and the prevalence of antimicrobial resistance showed significant differences among the 9 broiler breeder farms (P < 0.05). The tetM gene (77.1%) and ermB gene (85.0%) were detected at the highest levels in 179 TE-and 100 E-resistant isolates, respectively. Twenty-four high-level gentamicin-resistant isolates carried aac(6″)Ie-aph(2″)-la gene, and 9 high-level ciprofloxacin-resistant isolates showed point mutations in both gyrA and parC genes. All high-level gentamicin-resistant or high-level ciprofloxacin-resistant isolates showed one of the two different virulence gene patterns, ace-asa1-efaA-gelE complex or ace-efaA-gelE complex. These results indicate that constant epidemiological monitoring at the breeder level is required to prevent the pyramidal transmission of antimicrobial-resistant E. faecalis.


Assuntos
Antibacterianos/farmacologia , Galinhas , Farmacorresistência Bacteriana/genética , Enterococcus faecalis/efeitos dos fármacos , Variação Genética , Infecções por Bactérias Gram-Positivas/veterinária , Doenças das Aves Domésticas/epidemiologia , Animais , Farmacorresistência Bacteriana Múltipla/genética , Enterococcus faecalis/genética , Enterococcus faecalis/fisiologia , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Doenças das Aves Domésticas/microbiologia , Prevalência , República da Coreia/epidemiologia
17.
Gene ; 748: 144704, 2020 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-32339624

RESUMO

Resistance to antibiotics have created havoc around the globe due to the emergence of multi-drug resistant (MDR) pathogenic bacterial strains. To decipher this problem, a detailed understanding of the antimicrobial resistance (AMR) genes and their resistant mechanisms are obligatory. The present study is mainly focused on an opportunistic, nosocomial bacterial strain Enterococcus faecalis V583, which possess acquired exogenous AMR genes portraying resistance against Chloramphenicol, Tetracycline, Vancomycin, Linezolid, Ampicillin and other antibiotics. An interaction network of eight AMR genes along with 40 functional partners have been constructed and analysed. Functional enrichment analysis highlighted 20, 21 and 22 genes having significant roles in Cellular Component (CC), Molecular Functions (MF) and Biological Process (BP) respectively. Clustering analysis resulted in four densely interconnected clusters (C1-C4) which were associated with three AMR mechanisms that include the alteration in drug target (pbps, mur and van genes), complete replacement/bypass of target sites (van genes) and ATP Binding Cassette (ABC) transporter efflux pump mechanisms (msrA, EF_1680, EF_1682 and pbps). Our results showed that the genes responsible for ß-lactams resistance (pbp1A, 1C, 2A, 2B); glycopeptide resistance (ddl, vanBHBRBSBWXYB); Erythromycin, Macrolides, Lincosamide and Streptogramin-B (MLSB) resistance (msrA, EF_1680, EF_1682) along with mur genes (murABBCDEFG) played an important role in MDR mechanisms. Network analysis has shown the genes mraY, pbpC, murE, murG and murD possessed 26, 24, 23, 22 and 22 interactions respectively. With more number of direct interactions, these genes can be considered as hub genes that could be exploited as potential drug targets for new drug discovery.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Enterococcus faecalis/efeitos dos fármacos , Redes Reguladoras de Genes , Enterococcus faecalis/genética , Genes Bacterianos
18.
J Appl Oral Sci ; 28: e20190516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32236357

RESUMO

INTRODUCTION: This study investigated the effect of a calcium hydroxide (CH) paste (CleaniCal®) containing N-2-methyl pyrrolidone (NMP) as a vehicle on Enterococcus faecalis (E. faecalis) biofilms compared with other products containing saline (Calasept Plus™) or propylene glycol (PG) (Calcipex II®). METHODOLOGY: Standardized bovine root canal specimens were used. The antibacterial effects were measured by colony-forming unit counting. The thickness of bacterial microcolonies and exopolysaccharides was assessed using confocal laser scanning microscopy. Morphological features of the biofilms were observed using field-emission scanning electron microscopy (FE-SEM). Bovine tooth blocks covered with nail polish were immersed into the vehicles and dispelling was observed. The data were analyzed using one-way analysis of variance and Tukey tests (p<0.05). RESULTS: CleaniCal® showed the highest antibacterial activity, followed by Calcipex II® (p<0.05). Moreover, NMP showed a higher antibacterial effect compared with PG (p<0.05). The thickness of bacteria and EPS in the CleaniCal® group was significantly lower than that of other materials tested (p<0.05). FE-SEM images showed the specimens treated with Calasept Plus™ were covered with biofilms, whereas the specimens treated with other medicaments were not. Notably, the specimen treated with CleaniCal® was cleaner than the one treated with Calcipex II®. Furthermore, the nail polish on the bovine tooth block immersed in NMP was completely dispelled. CONCLUSIONS: CleaniCal® performed better than Calasept Plus™ and Calcipex II® in the removal efficacy of E. faecalis biofilms. The results suggest the effect might be due to the potent dissolving effect of NMP on organic substances.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Hidróxido de Cálcio/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Pirrolidinonas/farmacologia , Irrigantes do Canal Radicular/farmacologia , Análise de Variância , Animais , Cloreto de Cálcio/química , Cloreto de Cálcio/farmacologia , Hidróxido de Cálcio/química , Bovinos , Contagem de Colônia Microbiana , Combinação de Medicamentos , Teste de Materiais , Microscopia Confocal , Microscopia Eletrônica de Varredura , Cloreto de Potássio/química , Cloreto de Potássio/farmacologia , Pirrolidinonas/química , Reprodutibilidade dos Testes , Irrigantes do Canal Radicular/química , Bicarbonato de Sódio/química , Bicarbonato de Sódio/farmacologia , Cloreto de Sódio/química , Cloreto de Sódio/farmacologia , Estatísticas não Paramétricas
19.
BMC Biotechnol ; 20(1): 19, 2020 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228563

RESUMO

BACKGROUND: Foodborne pathogens and their biofilms are considered as one of the most serious problems in human health and food industry. Moreover, safety of foods is a main global concern because of the increasing use of chemical food additives. Ensuring food safety enhances interest in discovery of new alternative compounds such as antimicrobial peptides (AMPs), which can be used as bio-preservatives in the food industry. In this study, the most important antimicrobial peptides of camel milk lactoferrin (lactoferrampin and lactoferricin) were recombinantly expressed in the form of chimeric peptide (cLFchimera) in a food-grade L. lactis strain. P170 expression system was used to express secreted cLFchimera using pAMJ1653 expression vector which harbors a safe (non-antibiotic) selectable marker. RESULTS: Peptide purification was carried out using Ni-NTA agarose column from culture medium with concentration of 0.13 mg/mL. The results of disk diffusion test revealed that cLFchimera had considerable antimicrobial activity against a number of major foodborne bacteria. Furthermore, this chimeric peptide showed strong and weak inhibitory effect on biofilm formation against P. aeruginosa, S. aureus E. faecalis, and E. coli, respectively. Antioxidant activity and thermal stability of the chimeric peptide was determined. The results showed that cLFchimera had antioxidant activity (IC50: 310 µ/mL) and its activity was not affected after 40 min of boiling. Finally, we evaluated the interaction of the peptide with LPS and DNA in bacteria using molecular dynamic simulation as two main intra and extra cellular targets for AMPs, respectively. Our in silico analysis showed that cLFchimera had strong affinity to both of these targets by positive charged residues after 50 ns molecular dynamic simulation. CONCLUSIONS: Overall, the engineered food-grade L. lactis generated in the present study successfully expressed a secreted chimeric peptide with antimicrobial properties and could be considered as a promising bio-preservative in the food industry.


Assuntos
Peptídeos Catiônicos Antimicrobianos/metabolismo , Lactococcus lactis/crescimento & desenvolvimento , Lactoferrina/química , Fragmentos de Peptídeos/química , Engenharia de Proteínas/métodos , Animais , Peptídeos Catiônicos Antimicrobianos/genética , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biofilmes/efeitos dos fármacos , Camelus , Simulação por Computador , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Enterococcus faecalis/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Microbiologia de Alimentos , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
20.
J Zoo Wildl Med ; 51(1): 249-252, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32212573

RESUMO

An adult female spotted eagle ray (Aetobatus narinari) presented for medical evaluation due to a swelling located on the dorsal head. Ultrasound revealed that the swelling originated from a large pocket of fluid in the cranial vault. The swelling was aspirated, and purulent discharge was obtained; Enterococcus faecalis was cultured. An incision was made over the swelling in an attempt to drain fluid but was unsuccessful. Multiple aspirates were performed to drain the abscess, and the animal was treated with oxytetracycline injections. The initial incision sloughed and resulted in a large defect in the cranium that allowed exhibit water to come into the cranial vault and come in contact with the protective membrane of the brain. Forty-two days after initial presentation, the defect in the cranium was healed; fluid from the cranial vault was sampled and appeared normal. During and after treatment, the ray exhibited no abnormal neurologic signs.


Assuntos
Enterococcus faecalis/fisiologia , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/veterinária , Rajidae , Animais , Enterococcus faecalis/efeitos dos fármacos , Feminino , Doenças dos Peixes/cirurgia , Infecções por Bactérias Gram-Positivas/diagnóstico , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/cirurgia , Crânio/microbiologia , Crânio/cirurgia , Resultado do Tratamento
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