RESUMO
INTRODUCTION: Healthcare-associated infections are concerning adverse events and hand hygiene is considered an essential preventive measure. The objective of the present study was to assess the effect of a correct 3-step hand hygiene technique on reducing of potentially pathogenic microorganisms on hands related to the WHO five moments for hand hygiene. METHODOLOGY: A cross-sectional study was performed by means of direct observation involving 60 Intensive Care Units (ICU) and clinical nursing professionals in a Brazilian hospital. Observations were performed in order to ascertain the adherence rate and the correct technique during health assistance. Additionally, microbiological analysis of material collected from the nursing professional's hands was carried out. Exploratory and inferential analyses were performed on R software and binomial analysis was carried out by using the Z-test. The study was approved by the research ethics committee and covered all the legal principles for the protection of human subjects. RESULTS: Hand hygiene adherence rate was 63.3%. However, only 13.3% of the professionals performed the correct 3-step hand hygiene technique regarding steps and time. Sixty-five microorganisms were isolated, among which 56.9% were coagulase-negative Staphylococcus, 26.2% were Gram-negative bacilli, 7.7% were Enterococcus faecalis, and 6.2% were Candida parapsilosis. There was no presence of potentially pathogenic microorganisms on the nursing professional's hands who performed the correct three-step technique. CONCLUSIONS: Overall correct hand hygiene technique was poor. The results indicated the presence of potentially pathogenic microorganisms at moments in which hand hygiene was mandatory but was not executed or was executed incorrectly. The 3-step hand hygiene technique proved to be effective when correctly performed since there were no microorganism growth. Larger studies are needed to test if these results can be replicated at a larger scale, since streamlining hand hygiene technique yielded encouraging results.
Assuntos
Infecção Hospitalar , Higiene das Mãos , Humanos , Estudos Transversais , Brasil , Infecção Hospitalar/prevenção & controle , Enterococcus faecalisRESUMO
Silver phosphate and its composites have been attracting extensive interest as photocatalysts potentially effective against pathogenic microorganisms. The purpose of the present study was to investigate the mechanism of bactericidal action on cells of opportunistic pathogens. The Ag3PO4/P25 (AGP/P25) and Ag3PO4/HA (HA/AGP) powders were prepared via a co-precipitation method. Thereafter, their antimicrobial properties against Enterococcus faecalis, Staphylococcus epidermidis, and Staphylococcus aureus (clinical and reference strains) were analyzed in the dark and after exposure to visible light (VIS). The mechanism leading to cell death was investigated by the leakage of metabolites and potassium ions, oxidative stress, and ROS production. Morphological changes of the bacterial cells were visualized by transmission electron microscopy (TEM) and scanning transmission electron microscopy with energy-dispersive X-ray spectroscopy (SEM EDS) analysis. It has been shown that Ag3PO4-based composites are highly effective agents that can eradicate 100% of bacterial populations during the 60 min photocatalytic inactivation. Their action is mainly due to the production of hydroxyl radicals and photogenerated holes which lead to oxidative stress in cells. The strong affinity to the bacterial cell wall, as well as the well-known biocidal properties of silver itself, increase undoubtedly the antimicrobial potential of the Ag3PO4-based composites.
Assuntos
Parede Celular , Enterococcus faecalis , Morte Celular , Radical Hidroxila , LuzRESUMO
This study was to investigate the changes in gut microbiota in maintenance hemodialysis patients and analyze their impact on patient's microinflammation status. For this purpose, thirty-nine chronic kidney disease (CKD) maintenance hemodialysis patients admitted to our hospital from March 2019 to March 2022 were selected as the experimental group, and 40 healthy individuals with examination results during the same period were selected as the control group. The levels of gut microbiota (Lactobacillus, Bifidobacterium, Escherichia coli, and Enterococcus faecalis) and microinflammation indicators [interleukin-6 (IL-6), tumor necrosis factor α (TNF-α), and high-sensitivity C-reactive protein (hs-CRP)] were measured in both groups. The relationship between changes in gut microbiota and microinflammation in maintenance hemodialysis CKD patients was analyzed. Results showed that the levels of Lactobacillus and Bifidobacterium in the experimental group were significantly lower than those in the control group (all, P<0.05), while the levels of Escherichia coli and Enterococcus faecalis in the experimental group were significantly higher than those in the control group (all, P<0.05). The IL-6, TNF-α, and hs-CRP levels in the experimental group were significantly higher than those in the control group (all, P<0.05). Using microinflammation indicators as dependent variables and microbiota indicators as independent variables for stepwise regression analysis, the results showed that the levels of Lactobacillus were negatively correlated with IL-6 and TNF-α levels in patients (r=-0.358, -0.942, P<0.05); the levels of Bifidobacterium were negatively correlated with IL-6, TNF-α, and hs-CRP levels in patients (r=-0.394, -0.211, -0.547, P<0.05); the levels of Escherichia coli were positively correlated with IL-6 and TNF-α levels in patients (r=0.221, 0.268, P<0.05); the levels of Enterococcus faecalis were positively correlated with IL-6 and hs-CRP levels in patients (r=0.253, 0.378, P<0.05). In conclusion, patients with maintenance hemodialysis for CKD commonly exhibit gut microbiota dysbiosis and varying degrees of low-grade inflammation. Compared to healthy individuals, maintenance hemodialysis patients with CKD have lower levels of Bifidobacterium and Lactobacillus and higher levels of Escherichia coli and Enterococcus in their gut. Bifidobacterium, Lactobacillus, Escherichia coli, and Enterococcus all have a certain impact on the low-grade inflammation status of patients with maintenance hemodialysis for CKD.
Assuntos
Microbioma Gastrointestinal , Insuficiência Renal Crônica , Humanos , Proteína C-Reativa , Interleucina-6 , Fator de Necrose Tumoral alfa , Enterococcus , Enterococcus faecalis , Escherichia coli , Inflamação , Lactobacillus , Diálise RenalRESUMO
Enterococcus faecalis is a commensal bacterium commonly found in the human gastrointestinal tract. However, in individuals with compromised immune systems, the pathogen can lead to severe illness. This opportunistic pathogen is associated with secondary apical diseases and is adept at resisting antibiotics and other forms of treatment because of its numerous virulence factors. Enterococcus faecalis is capable of disrupting the normal functions of immune cells, thereby hindering the body's ability to eradicate the infection. However, intensive research is needed in further understanding the adverse immunomodulatory effects of E. faecalis. Potential strategies specific for eradicating E. faecalis have proven beneficial in the treatment of persistent secondary apical periodontitis.
Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Periodontite Periapical , Humanos , Enterococcus faecalis , Bactérias , Antibacterianos/farmacologia , Antibacterianos/uso terapêuticoRESUMO
The aim of this study was to evaluate the prevalence of Enterococcus species in the mouth of adults with periodontal health and periodontitis. A systematic search was made in databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search for articles was conducted in Medline/PubMed, Latin American and Caribbean Health Sciences Literature Database (LILACS), Cochrane Library, Scopus, Embase, Web of Science databases and in the System of Information on Grey Literature in Europe (SINGLE) and included articles published in English up to April 25th, 2021. Observational studies in humans with and without periodontitis were evaluated to identify the prevalence of Enterococcus species. Articles that met the inclusion criteria were analyzed and classified to determine the quality rating in good, fair, and poor. A new detailed checklist for quality assessment was developed based on the information required for applicable data extraction in reviews. The study design, sample size, demographic data, periodontal clinical parameters, microbial analysis method, biological sample, prevalence of Enterococcus spp., and correlations with periodontal clinical parameters were assessed. After screening and full-text reading, 8 articles met the inclusion criteria. All selected studies showed a significantly higher prevalence of Enterococcus spp. in patients with periodontitis compared with periodontally healthy patients. Thus, the present systematic review suggests that the prevalence of Enterococcus faecalis in the mouth of periodontitis individuals is higher than that of periodontally healthy individuals.
Assuntos
Enterococcus , Periodontite , Humanos , Adulto , Prevalência , Periodontite/epidemiologia , Enterococcus faecalisRESUMO
Innate immune priming increases an organism's survival of a second infection after an initial, non-lethal infection. We used Drosophila melanogaster and an insect-derived strain of Enterococcus faecalis to study transcriptional control of priming. In contrast to other pathogens, the enhanced survival in primed animals does not correlate with decreased E. faecalis load. Further analysis shows that primed organisms tolerate, rather than resist infection. Using RNA-seq of immune tissues, we found many genes were upregulated in only primed flies, suggesting a distinct transcriptional program in response to initial and secondary infections. In contrast, few genes continuously express throughout the experiment or more efficiently re-activate upon reinfection. Priming experiments in immune deficient mutants revealed Imd is largely dispensable for responding to a single infection but needed to fully prime. Together, this indicates the fly's innate immune response is plastic-differing in immune strategy, transcriptional program, and pathway use depending on infection history.
Assuntos
Proteínas de Drosophila , Drosophila melanogaster , Animais , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Enterococcus faecalis/genética , Enterococcus faecalis/metabolismo , Imunidade Inata , Tolerância ImunológicaRESUMO
Enterococcus faecalis has emerged as an important opportunistic pathogen due to its increasing resistance to antimicrobials, mainly to vancomycin, which leads substantial cases of therapeutic failures. Wastewater treatment plants (WWTP), in turn, are considered hotpots in the spread of antimicrobial resistance according to One Health perspective. In this study, we present the first report of a vancomycin-resistant E. faecalis strain recovered from treated effluent in Brazil. For this purpose, the whole-genome sequencing (WGS) was carried out aiming to elucidate its molecular mechanisms of antimicrobial resistance and its phylogenetic relationships amongst strains from other sources and countries. According to Multilocus Sequence Typing (MLST) analysis this strain belongs to ST21. The WGS pointed the presence of vanA operon, multiple antibiotic resistance and virulence genes, and a significant pathogenic potential for humans. The phylogenomic analysis of E. faecalis 6805 was performed with ST21 representatives from the PubMLST database, including the E. faecalis IE81 strain from clinical sample in Brazil, which had its genome sequenced in this study. Our results demonstrated a strain showing resistance to vancomycin in treated effluent. To the best of our knowledge, this is an unprecedented report of vanA-carrying E. faecalis ST21. Furthermore, it is the first description of a vanA-harboring strain of this species from environmental sample in Brazil. Our data highlight the role of WWTP in the spread of AMR, since these environments are favorable for the selection of multidrug-resistant pathogens and the treated effluents, carrying antibiotic resistance genes, are directed to receiving water bodies.
Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Humanos , Enterococcus faecalis/genética , Vancomicina , Tipagem de Sequências Multilocus , Brasil , Filogenia , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Resistência a Vancomicina/genéticaRESUMO
BACKGROUND: Thorough disinfection of root canals in primary molars may be complicated by the complex root canal morphology. This in-vitro study aimed to compare direct and residual antimicrobial effect of 2% chlorhexidine (CHX) gel, 500 mg/ml double antibiotic paste (DAP) and chitosan-chlorhexidine nanoparticles (CS-CHX NPs) as intracanal medicaments against Enterococcus faecalis (E. faecalis) and Candida albicans (C. albicans) in primary molars. METHODS: Mesial roots of 63 mandibular second primary molars were infected with E. faecalis and C. albicans. Teeth were divided into 9 groups: Ia: (CS-CHX NPs), IIa: (CHX), IIIa: (DAP), IVa: chitosan nanoparticles (CSNPs) in which medicaments were placed for 3 days, groups Ib: (CS-CHX NPs), IIb: CHX, IIIb: (DAP), IVb: (CSNPs) in which medicaments were placed for 7 days, and Group V (control): teeth were infected, irrigated with saline, and sampled 3- and 7-days post-infection. Microbiological samples were obtained after infection, 3, and 7 days after medicament placement and 7 days after medicament removal for both time points. One-way ANOVA, Tukey's post hoc test and paired t-test were used at p < 0.05. RESULTS: CS-CHX NPs had the highest anticandidal effect which was comparable to CHX and significantly higher than other medicaments (p < 0.001) at both time points. CS-CHX NPs had the highest effect against E. faecalis which was comparable to DAP and significantly higher than other medicaments (p < 0.001) at 3 days. All medicaments showed similar effect against E. faecalis after 7 days. The 7-days placement significantly increased the antimicrobial effect against both micro-organisms in all groups, except CS-CHX NPs which showed an insignificant increase. CS-CHX NPs showed the highest residual effect against both micro-organisms that increased with 7-days placement. CONCLUSION: CSNPs and CHX combination showed a synergistic effect against both micro-organisms. CS-CHX NPs displayed a higher effect at a shorter period compared to other medicaments, yet its residual effect was higher with 7-days placement.
Assuntos
Quitosana , Clorexidina , Humanos , Clorexidina/farmacologia , Clorexidina/uso terapêutico , Antibacterianos/farmacologia , Candida albicans , Enterococcus faecalis , Quitosana/farmacologia , Quitosana/uso terapêutico , Cavidade Pulpar/microbiologia , Irrigantes do Canal Radicular/farmacologia , Irrigantes do Canal Radicular/uso terapêutico , Hidróxido de Cálcio/farmacologiaRESUMO
The present research investigated whether accidental contact through stinging with honeybees, wasps, and hornets could represent a microbial hazard for humans. It has been previously suggested that such contact may transmit pathogens causing infections that could even be fatal for some susceptible individuals. Stinging simulation experiments were performed in the lab with live insects collected from the environment in Lemnos Island (north-eastern Greece), while different selective agar media targeting some clinically important bacteria (i.e., Staphylococcus aureus, Streptococcus pyogenes, Enterococcus faecalis/faecium, and Pseudomonas aeruginosa) were used as substrates for microbial recovery and identification. Results revealed none of the target pathogenic bacterial species in the honeybee samples, with bacilli, staphylococci, and micrococci dominating their surveyed microbiota. However, most of the suspect colonies isolated from wasps and hornets belonged to important hygienic indicators (i.e., enterococci, Proteus mirabilis, and coliforms), implying possible contact of these insects with fecal origin materials. To sum up, the microbiota that may be transmitted to humans through stinging appears to differ between honeybees and wasps/hornets, while the isolation from the latter samples of some other important opportunistic pathogens, such as Enterobacter spp. and Klebsiella spp., also known for multidrug resistance, could be an additional reason of concern.(AU)
Assuntos
Humanos , Abelhas , Microbiota , Vespas , Pseudomonas aeruginosa , Enterococcus faecium , Enterococcus faecalis , Microbiologia , Técnicas Microbiológicas , Mordeduras e Picadas , Staphylococcus aureusRESUMO
The aim of the present study was to evaluate, in vitro, the antimicrobial activity of the probiotic Bifidobacterium animalis subsp. lactis HN019, through the well technique, against 10 microorganisms can be found involved in endodontic infections. The antimicrobial activity of the probiotic was performed on Streptococcus mutans, Streptococcus sobrinus, Lacticaseibacillus casei, Enterococcus faecalis, Staphylococcus aureus, Candida albicans, Porphyromonas gingivalis, Porphyromonas endodontalis, Fusobacterium nucleatum and Prevotella intermedia. For the control group, it was used non-pathogenic bacteria Escherichia coli, Saccharomyces cerevisiae, and Kocuria rizhopilla. After 48 to 72 h of incubation of the petri dishes containing the culture medium, the microorganism strains, and the probiotic, the plates were examined to assess the uniformity of microbial growth, presence of contaminants, and the halo of inhibition. After visual inspection, the reading of the halo of inhibition was performed with the aid of a digital caliper using a reflected light source to illuminate the inverted plate on a black, opaque background after removing the cap. Thus, 3 values were obtained from each bacterial inoculum, which were added and divided by three to obtain the average of the values. The results of the in vitro study demonstrated that the probiotic B. animalis subsp. lactis HN019 promoted the inhibition of all strains of the pathogens evaluated, with the exception of Candida albicans, demonstrating antimicrobial activity on these microorganisms.
Assuntos
Anti-Infecciosos , Bifidobacterium animalis , Candida albicans , Meios de Cultura , Enterococcus faecalis , Escherichia coli , Anti-Infecciosos/farmacologiaRESUMO
Proteolytic degradation of semenogelins, the most abundant proteins from human semen, results in the formation of 26- and 29-amino acid peptides (SgIIA and SgI-29, respectively), which share a common 15 amino acid fragment (Sg-15). All three ligands are effective Zn(II) and Cu(II) binders; in solution, a variety of differently metalated species exist in equilibrium, with the [NH2, 3Nim] donor set prevailing at physiological pH in the case of both metals. For the first time, the Cu(II)-induced antimicrobial activity of Sg-15 against Enterococcus faecalis is shown. In the case of the two native semenogelin fragment metal complexes, the strong local positive charge in the metal-bound HH motif correlates well with their antimicrobial activity. A careful analysis of semenogelins' metal coordination behavior reveals two facts: (i) The histamine-like Cu(II) binding mode of SgI-29 strongly increases the stability of such a complex below pH 6 (with respect to the non-histamine-like binding of SgIIA), while in the case of the SgI-29 Zn(II)-histamine-like species, the stability enhancement is less pronounced. (ii) The HH sequence is a more tempting site for Cu(II) ions than the HXH one.
Assuntos
Anti-Infecciosos , Enterococcus faecalis , Humanos , Cobre/química , Química Bioinorgânica , Zinco/químicaRESUMO
The emergence of infections caused by microorganisms in the oral cavity and increasing concerns regarding the use of antibiotics have resulted in the development of novel antimicrobial molecules, such as antimicrobial synthetic peptides. The purpose of this study was to evaluate the antimicrobial and antibiofilm activities of the native peptide KR-12 and its derivative, the synthetic peptide [W7]KR12-KAEK, against planktonic and biofilms Enterococcus faecalis strains. The methods used to evaluate the antimicrobial activity in planktonic cultures include minimum inhibitory concentration and minimum bactericidal concentration assays. The effects of [W7]KR12-KAEK on biofilm formation and mature biofilms were evaluated by quantifying biomass (crystal violet staining) and counting colony-forming units. Structural assessments of the biofilms and cellular morphological changes were performed using scanning electron microscopy. Peptide [W7]KR12-KAEK showed potential antimicrobial activity against planktonic cells. Interestingly, the native peptide KR-12 showed no antimicrobial activity. Moreover, it inhibited biofilm formation and disrupted the mature biofilms of E. faecalis strains. These results suggest that [W7]KR12-KAEK may be a potential molecule for the development of auxiliary antimicrobial therapies against oral infections.
Assuntos
Anti-Infecciosos , Enterococcus faecalis , Anti-Infecciosos/farmacologia , Peptídeos , Biofilmes , PlânctonRESUMO
Enterococcus species are known for their ability to form biofilms, which contributes to their survival in extreme environments and involvement in persistent bacterial infections, especially in the case of multi-drug-resistant strains. This review aims to provide a comprehensive understanding of the mechanisms underlying biofilm formation in clinically important species such as Enterococcus faecalis and the less studied but increasingly multi-drug-resistant Enterococcus faecium, and explores potential strategies for their eradication. Biofilm formation in Enterococcus involves a complex interplay of genes and virulence factors, including gelatinase, cytolysin, Secreted antigen A, pili, microbial surface components that recognize adhesive matrix molecules (MSCRAMMs), and DNA release. Quorum sensing, a process of intercellular communication, mediated by peptide pheromones such as Cob, Ccf, and Cpd, plays a crucial role in coordinating biofilm development by targeting gene expression and regulation. Additionally, the regulation of extracellular DNA (eDNA) release has emerged as a fundamental component in biofilm formation. In E. faecalis, the autolysin N-acetylglucosaminidase and proteases such as gelatinase and serin protease are key players in this process, influencing biofilm development and virulence. Targeting eDNA may offer a promising avenue for intervention in biofilm-producing E. faecalis infections. Overall, gaining insights into the intricate mechanisms of biofilm formation in Enterococcus may provide directions for anti-biofilm therapeutic research, with the purpose of reducing the burden of Enterococcus-associated infections.
Assuntos
Biofilmes , Enterococcus , Enterococcus/genética , Enterococcus/metabolismo , Enterococcus faecalis/metabolismo , Percepção de Quorum , Gelatinases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismoRESUMO
Daptomycin is a cyclic lipodepsipeptide antibiotic reserved for the treatment of serious infections by multidrug-resistant Gram-positive pathogens. Its mode of action is considered to be multifaceted, encompassing the targeting and depolarization of bacterial cell membranes, alongside the inhibition of cell wall biosynthesis. To characterize the daptomycin mode of action, 15N cross-polarization at magic-angle spinning NMR measurements were performed on intact whole cells of Staphylococcus aureus grown in the presence of a sub-inhibitory concentration of daptomycin in a chemically defined media containing L-[ϵ-15N]Lys. Daptomycin-treated cells showed a reduction in the lysyl-ε-amide intensity that was consistent with cell wall thinning. However, the reduced lysyl-ε-amine intensity at 10 ppm indicated that the daptomycin-treated cells did not accumulate in Park's nucleotide, the cytoplasmic peptidoglycan (PG) precursor. Consequently, daptomycin did not inhibit the transglycosylation step of PG biosynthesis. To further elucidate the daptomycin mode of action, the PG composition of daptomycin-susceptible Enterococcus faecalis grown in the presence of daptomycin was analyzed using liquid chromatography-mass spectrometry. Sixty-nine muropeptide ions correspond to PG with varying degrees of modifications including crosslinking, acetylation, alanylation, and 1,6-anhydrous ring formation at MurNAc were quantified. Analysis showed that the cell walls of daptomycin-treated E. faecalis had a significant reduction in PG crosslinking which was accompanied by an increase in lytic transglycosylase activities and a decrease in PG-stem modifications by the carboxypeptidases. The changes in PG composition suggest that daptomycin inhibits cell wall biosynthesis by impeding the incorporation of nascent PG into the cell walls by transpeptidases and maturation by carboxypeptidases. As a result, the newly formed cell walls become highly susceptible to degradation by the autolysins, resulting in thinning of the cell wall.
Assuntos
Daptomicina , Daptomicina/farmacologia , Enterococcus faecalis , Antibacterianos/metabolismo , Peptidoglicano/metabolismo , Parede Celular/metabolismoRESUMO
To investigate the occurrence of oxazolidinone resistance genes, 18 florfenicol-resistant enterococci were isolated from 66 fecal samples collected from several cattle farms in central Italy. The PCR screening indicated that only a bovine florfenicol-resistant isolate, Enterococcus faecium 249031-C, was positive for the presence of optrA and poxtA genes. The strain was tested for its susceptibility to florfenicol, chloramphenicol, linezolid, tedizolid, tetracycline, erythromycin, and vancomycin. Whole Genome Sequencing analysis showed that E. faecium 249031-C, belonging to the ST22 lineage, harbored two plasmids: the optrA-carrying p249031-S (179 kb) and the poxtA-carrying p1818-c (23 kb). p249031-S, containing a new optrA-carrying Tn7695 transposon, was closely related to the plasmid pF88_1 of E. faecium F88, whereas p1818-c had already been detected in a human E. faecium, both enterococci were from Switzerland. The linezolid resistance genes were cotransferred to the E. faecium 64/3 recipient. Circular forms from both optrA- and poxtA-carrying genetic contexts were obtained. The occurrence of oxazolidinone resistance genes in a bovine E. faecium isolate and their localization on conjugative and mobilizable plasmids pose a risk for public health.
Assuntos
Enterococcus faecium , Oxazolidinonas , Bovinos , Animais , Humanos , Enterococcus , Antibacterianos/farmacologia , Linezolida/farmacologia , Suíça , Enterococcus faecalis , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , FezesRESUMO
Background: Sealers with antimicrobial properties play an important role in endodontic therapy success especially against Enterococcus faecalis infection found in failed root canal therapy. Addition of antibiotic agents to endodontic sealers may show significant increase in their antibacterial properties both against anaerobic and aerobic microbes. The purpose of the present study was to evaluate antimicrobial efficacy of Kerr pulp canal sealer (EWT) in combination with 10% amoxicillin against E. faecalis and post-root canal treatment viability of Enterococcus faecalis on the first and seventh day. Methods: A total of 60 extracted human mandibular premolar teeth were decoronated after initial decontamination with 1% NaOCl. Root length standardized to 12 mm. Canal instrumentation was done using ProTaper Universal file system till size F2 using 5.25% NaOCl. It was then infected with a pure strain of E. faecalis for a period of four days. Obturation was done using plain sealer, (n=30) and sealer-antibiotic combination, (n=30). Half of the teeth were sectioned at 24 hours (S, SA) and other half were sectioned seven days after obturation (S7, SA7). All samples were stained with SYTO9 and propidium iodide for imaging under Confocal Laser Scanning microscope. Statistical analysis was performed with the statistical software SPSS v. 17.0 (SPSS for Windows; SPSS Inc, Chicago, IL). Data was analysed using One Way ANOVA and post hoc Tukey test to determine statistical significance with p value < 0.01 considered significant. Results: Statistically significant differences were observed in green to red ratio between group S (9.561976) and S7 (0.435418) (p < 0.01). There was no difference found between SA (mean of green to red ratio, (0.70431) and SA7 (mean of green to red ratio, 0.85184). Conclusions: Antibiotics added to the sealer effectively eradicated of E. faecalis 24 hours post-obturation. However, after seven days, plain sealer was as effective as sealer-antibiotic combination.
Assuntos
Anti-Infecciosos , Materiais Restauradores do Canal Radicular , Humanos , Amoxicilina/farmacologia , Enterococcus faecalis , Materiais Restauradores do Canal Radicular/farmacologia , Resinas Epóxi/farmacologia , Antibacterianos/farmacologiaRESUMO
Bacteria possess elaborate systems to manage reactive oxygen and nitrogen species (ROS) arising from exposure to the mammalian immune system and environmental stresses. Here we report the discovery of an ROS-sensing RNA-modifying enzyme that regulates translation of stress-response proteins in the gut commensal and opportunistic pathogen Enterococcus faecalis. We analyze the tRNA epitranscriptome of E. faecalis in response to reactive oxygen species (ROS) or sublethal doses of ROS-inducing antibiotics and identify large decreases in N2-methyladenosine (m2A) in both 23 S ribosomal RNA and transfer RNA. This we determine to be due to ROS-mediated inactivation of the Fe-S cluster-containing methyltransferase, RlmN. Genetic knockout of RlmN gives rise to a proteome that mimics the oxidative stress response, with an increase in levels of superoxide dismutase and decrease in virulence proteins. While tRNA modifications were established to be dynamic for fine-tuning translation, here we report the discovery of a dynamically regulated, environmentally responsive rRNA modification. These studies lead to a model in which RlmN serves as a redox-sensitive molecular switch, directly relaying oxidative stress to modulating translation through the rRNA and the tRNA epitranscriptome, adding a different paradigm in which RNA modifications can directly regulate the proteome.
Assuntos
Enterococcus faecalis , Proteoma , Animais , Espécies Reativas de Oxigênio , Enterococcus faecalis/genética , Proteoma/genética , Estresse Oxidativo/genética , Processamento Pós-Transcricional do RNA , Adenosina , Proteínas de Choque Térmico , MamíferosRESUMO
The Aloe vera plant is a cactus-like plant in the Liliacea family that has been known and utilized for its medical benefits. It has been attempted to be used as a remineralizing agent and shows an antibacterial effect. Aim of the study - assessment of the remineralizing effect of solution of saturated Aloe vera gel compared to distal water by microhardness Vickers test and Densometric X-Ray Analysis and effect of Aloe vera gel against Enterococcus faecalis. 10 extracted permanent molars were used in this in vitro study. each tooth enrolls in Teflon tape and only the enamel of the occlusal surface was exposed to a demineralizing solution (acid etch) for 45 seconds in-vitro and randomly assigned to two groups: Group 1 was treated with distal water; group 2 was treated with Aloe vera gel. All groups except the control baseline group were treated with their respective remineralizing solution for 10 days. Vicker's Microhardness Number (VHN) and Densometric X-Ray Analysis were carried out at baseline, post-demineralization and later post 10 days of remineralization. The antibacterial effect of Aloe vera gel was assessed by the disc diffusion method. The filter paper was immersed in 20µl of different concentrations of Aloe vera gel extract as fresh Aloe vera (100 %) and (50 % and 25 %) diluted with de-ionized water after that the disc was distributed in a plate containing the E. faecalis. Antibiotics disc of Augmentin (Amoxicillin and Clavulanic acid 30ug) were also poured in the same plate and incubated at 37°C for 24 hours and the zone of inhibition of antibiotic was measured for comparison with a zone of inhibition of filter paper saturated with Aloe vera gel. Densitometric X-Ray Analysis and Microhardness Number (VHN) evaluation showed improvement in the enamel density and the surface hardness after remineralization. The mean value in the group treated with Aloe vera solution was higher than the recorded mean value for the group treated with distal water. There was a significant difference between Aloe vera solution and distal water. Significant (p-value≤0.05) after 10 days. The antibacterial effect showed that E. faecalis was resistant to Aloe vera gel in different concentrations compared with Augmentin (Amoxicillin and Clavulanic acid 30ug). Aloe vera gel could be used for caries prevention in terms of safety and efficiency. While E. faecalis show resistance activity against Aloe vera gel.
Assuntos
Combinação Amoxicilina e Clavulanato de Potássio , Enterococcus faecalis , Combinação Amoxicilina e Clavulanato de Potássio/farmacologia , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Amoxicilina/farmacologiaRESUMO
Multiple episodes of Enterococcus faecalis bacteremia (EfsB) may indicate a relapse and be due to an undiagnosed infective endocarditis (IE). The aims were to study the clinical presentation of patients with EfsB with focus on the risk of recurrent infection and IE, identify potential improvements of the management, and to investigate whether E. faecalis isolates from different episodes in the same patient were identical. In a retrospective study, a cohort of patients with monomicrobial (M) EfsB episodes was analyzed. Clinical data from medical records were collected. Furthermore, blood culture isolates from patients with multiple episodes were subjected to whole genome sequencing and multilocus sequence typing. In 666 episodes of MEfsB, 69 patients with IE and 43 with recurrent infections were found. Patients without IE, but with a following episode diagnosed as IE, were compared to those without a following episode. Variables significantly correlated with IE were long duration of symptoms, growth in all blood cultures, unknown origin of infection, heart murmur, and predisposition for IE. Transesophageal echocardiography, all negative, was done in 4 out of 11 episodes during the first episodes, later diagnosed with IE. In 28 of 31 patients with two or more EfsB episodes, isolates with identical sequence type were found. Episodes of EfsB in patients later diagnosed with IE showed features of IE already during the first episodes, were not adequately evaluated, are due to identical isolates, and most likely represent true relapses. Risk factor analysis should guide the use of echocardiography.
Assuntos
Bacteriemia , Endocardite Bacteriana , Endocardite , Infecções por Bactérias Gram-Positivas , Humanos , Enterococcus faecalis/genética , Estudos Retrospectivos , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Endocardite/diagnóstico , Endocardite Bacteriana/diagnóstico , Endocardite Bacteriana/epidemiologia , Endocardite Bacteriana/microbiologia , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , GenômicaRESUMO
AIM: This in-vitro investigation aimed to assess the antibacterial effectiveness of photo-sonodynamic treatment using methylene blue (MTB)-incorporated poly(D, L-Lactide-Co-Glycolide) acid (PLGA)-nanoparticles for the disinfection of root canals. METHODS: The synthesis of PLGA nanoparticles was achieved using a solvent displacement technique. The morphological and spectral characterization of the formulated PLGA nanoparticles were carried out using scanning electron microscopy (SEM) and Transformed-Fourier infrared spectroscopy (TFIR), respectively. One hundred human premolar teeth were sterilized and then their root canals were infected with Enterococcus faecalis (E. faecalis). Later, the bacterial viability evaluation of the following 5 research groups was conducted: (a) G-1: specimens treated with a diode laser; (b) G-2: specimens treated with antimicrobial photodynamic therapy (aPDT) and 50 µg/mL of MTB-incorporated PLGA nanoparticles; (c) G-3: specimens treated with ultrasound (US); (d) G-4: specimens treated with US and 50 µg/mL of MTB-incorporated PLGA nanoparticles; and (e) G-5: control group consisting of specimens that did not undergo any treatment. RESULTS: Under SEM, the nanoparticles exhibited a uniform spherical shape and were around 100 nm. The formulated nanoparticles' size was validated through zeta potential analysis utilizing dynamic light scattering (DLS). The TFIR images of both PLGA nanoparticles and MTB-incorporated PLGA nanoparticles exhibited absorption bands ranging from around 1000 to 1200/cm and nearly from 1500 to 1750/cm. The G-5 samples (control group) demonstrated the greatest viability against E. faecalis, followed by G-3 (US-conditions specimens), G-1 (diode laser-conditioned specimens), G-2 (aPDT + MTB-incorporated PLGA-nanoparticles-conditioned specimens), and G-5 (US + MTB-incorporated PLGA-nanoparticles-conditioned specimens). Significant statistical differences (p < 0.05) were observed among all research groups, including both the experimental groups and control group. CONCLUSION: The combination of US via MTB-incorporated PLGA nanoparticles exhibited the most effective eradication of E. faecalis, suggestive of a promising therapeutic modality against E. faecalis for disinfecting root canals with complex and challenging anatomy.
