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Advances in Clinical and Experimental... Feb 2019Actinomyces species have a low virulence and pathogenicity, but under specific circumstances they may be involved in root canal and periapical tissue infections. (Comparative Study)
Comparative Study
BACKGROUND
Actinomyces species have a low virulence and pathogenicity, but under specific circumstances they may be involved in root canal and periapical tissue infections.
OBJECTIVES
The aim of the study was to investigate the antibacterial activity of various root canal sealers on standardized strains of Actinomyces.
MATERIAL AND METHODS
The materials tested in this study included AH Plus™ Jet (AH), Apexit® Plus (AP), Endomethasone N (EN), GuttaFlow® (GF), Hybrid Root SEAL (HB), MTA Fillapex (FL), Real® Seal (RCS), Roeko Seal Automix (RSA), Sealapex™ (SP), and Tubli-Seal™ (TS). The antibacterial effect of the freshly mixed sealers on standardized strains of Actinomyces israelii NCTC 8047 and Actinomyces viscosus ATCC 15987 was evaluated with the use of the agar diffusion test (ADT). The results were obtained by measuring the diameter of the growth inhibition zone at 96 h and 1, 2, 3, and 4 weeks, and were analyzed in time using repeated measures analysis of variance (ANOVA). Statistically significant differences among the materials were determined by using one-way ANOVA and Tukey's post hoc testing. A paired Student's t-test was applied to compare the susceptibility of particular strains to each sealer. The critical level of significance for all tests was p < 0.05.
RESULTS
Most sealers demonstrated growth inhibition zones against both tested bacteria, except for RSA and GF. Actinomyces viscosus was significantly more susceptible than A. israelii to AP, RCS (p < 0.001) and TS (p = 0.012). Actinomyces israelii was significantly more susceptible than A. viscosus to EN, HB and SP (p < 0.001).
CONCLUSIONS
The antimicrobial effect of the examined materials varied considerably depending on the type of material and bacterial species tested. Most of the tested root canal sealers exhibited antibacterial activity on standardized strains of Actinomyces, with FL showing the highest antibacterial effect on both bacterial strains. Importantly, both standardized strains of Actinomyces were characterized by varied sensitivity to root canal sealers.
Topics: Actinomyces; Anti-Bacterial Agents; Colony Count, Microbial; Dental Pulp Cavity; Humans; Root Canal Filling Materials
PubMed: 30085427
DOI: 10.17219/acem/78022 -
The Journal of Contemporary Dental... Jul 2018To study the antimicrobial effect of chlorhexidine diacetate (CHX-D)-modified type II glass ionomer cement (GIC) against the two predominant deep caries microorganisms,...
AIM
To study the antimicrobial effect of chlorhexidine diacetate (CHX-D)-modified type II glass ionomer cement (GIC) against the two predominant deep caries microorganisms, namely Lactobacillus casei and Actinomyces viscosus.
MATERIALS AND METHODS
An experimental GIC (ex-GIC) was prepared by mixing CHX-D powder with the powder of type II GIC to obtain 1% (w/w) concentration of CHX-D in the GIC. Antibacterial activity of this ex-GIC was tested against L. casei and A. viscosus using the agar diffusion method. The ex-GIC specimens were tested in their unset and set forms for each bacterium. For the unset group, specimens were placed in each agar plate immediately after manipulation and for the set group, specimens were placed in each agar plate, 1 hour after manipulation. The inhibition zones on the agar plate were recorded in millimeters immediately on placement of the specimen in the agar plate and after 48 hours. The reading was recorded and statistically analyzed for significant difference.
RESULTS
Mann-Whitney U test showed statistically significant difference in the inhibition zones produced by ex-GIC against L. casei and A. viscosus when both were compared in unset (p-value = 0.002) and set (p-value = 0.031) groups. For both the groups, the zone of inhibition against L. casei was greater. Though the unset group recorded wider zone of inhibition, the difference was not significant when compared with the respective set group. This was true for both the bacterial groups.
CONCLUSION
The 1% CHX-D-modified type II GIC showed antibacterial property against L. casei and A. viscosus and significantly higher activity against L. casei.
CLINICAL SIGNIFICANCE
Addition of 1% CHX-D to type II GIC showed evidence of antibacterial activity against organisms found in deep carious lesion and therefore may exhibit superior antimicrobial efficiency when used as an intermediate therapeutic restoration in deep cavities.
Topics: Actinomyces viscosus; Agar; Anti-Bacterial Agents; Chlorhexidine; Dental Caries; Dose-Response Relationship, Drug; Drug Resistance, Bacterial; Glass Ionomer Cements; Humans; Lacticaseibacillus casei; Microbial Sensitivity Tests
PubMed: 30066686
DOI: No ID Found -
American Journal of Ophthalmology Aug 2018To evaluate microbiota colonizing soft contact lenses (CL) in eyes with Boston type I keratoprosthesis (BKPro), and determine the prevalence of resistance to...
PURPOSE
To evaluate microbiota colonizing soft contact lenses (CL) in eyes with Boston type I keratoprosthesis (BKPro), and determine the prevalence of resistance to fourth-generation fluoroquinolone (FQ).
DESIGN
Prospective, observational study.
SUBJECTS
Patients with BKPro using CL as routine who were in postoperative follow-up in the Department of Ophthalmology of the Federal University of Sao Paulo, and volunteered to participate in the study. All patients were under a prophylactic scheme of topical 0.5% moxifloxacin 3 times a day and topical 5% povidone-iodine (PI) at the time of CL exchange.
METHODS
Patients on scheduled replacement scheme of CL had their lenses removed and sent for microbiological analysis. Standard culture methods were used for microorganism identification and susceptibility to different antibiotics was tested. Main outcome measure was prevalence of resistance to fourth-generation FQ.
RESULTS
Among the 19 eyes, 12 eyes (63%) had at least 1 positive bacterial culture. The most prevalent isolates were Staphylococcus epidermidis and other coagulase-negative staphylococci. Actinomyces viscosus was isolated in 1 CL. Fungal cultures were all negative. Of the 12 eyes with culture bacterial growth, resistance to fourth-generation FQ (0.5% moxifloxacin) was identified in 6 different eyes (50%). None presented infectious complications.
CONCLUSIONS
FQ-resistant bacteria were isolated in some patients. Although our prophylactic antibiotic regimen has been efficient in preventing bacterial infection, this analysis demonstrated that prophylaxis with PI and low FQ dose might increase resistance to antibiotics. Investigations in this field may help to outline future changes of prophylactic guidelines and therapeutic strategies.
Topics: Aged; Anti-Bacterial Agents; Artificial Organs; Bacteria; Contact Lenses, Hydrophilic; Cornea; Drug Resistance, Bacterial; Female; Follow-Up Studies; Humans; Male; Microbial Sensitivity Tests; Microbiota; Middle Aged; Moxifloxacin; Postoperative Period; Prospective Studies; Prostheses and Implants
PubMed: 29856980
DOI: 10.1016/j.ajo.2018.05.021 -
PloS One 2018Recent developments in High-Throughput DNA sequencing (HTS) technologies and ancient DNA (aDNA) research have opened access to the characterization of the microbial...
Recent developments in High-Throughput DNA sequencing (HTS) technologies and ancient DNA (aDNA) research have opened access to the characterization of the microbial communities within past populations. Most studies have, however, relied on the analysis of dental calculus as one particular material type particularly prone to the molecular preservation of ancient microbial biofilms and potential of entire teeth for microbial characterization, both of healthy communities and pathogens in ancient individuals, remains overlooked. In this study, we used shotgun sequencing to characterize the bacterial composition from historical subjects showing macroscopic evidence of oral pathologies. We first carried out a macroscopic analysis aimed at identifying carious or periodontal diseases in subjects belonging to a French rural population of the 18th century AD. We next examined radiographically six subjects showing specific, characteristic dental pathologies and applied HTS shotgun sequencing to characterize the microbial communities present in and on the dental material. The presence of Streptococcus mutans and also Rothia dentocariosa, Actinomyces viscosus, Porphyromonas gingivalis, Tannerella forsythia, Pseudoramibacter alactolyticus, Olsenella uli and Parvimonas micra was confirmed through the presence of typical signatures of post-mortem DNA damage at an average depth-of-coverage ranging from 0.5 to 7X, with a minimum of 35% (from 35 to 93%) of the positions in the genome covered at least once. Each sampled tooth showed a specific bacterial signature associated with carious or periodontal pathologies. This work demonstrates that from a healthy independent tooth, without visible macroscopic pathology, we can identify a signature of specific pathogens and deduce the oral health status of an individual.
Topics: DNA, Ancient; DNA, Bacterial; Dental Caries; Female; France; Health Status; History, 18th Century; Humans; Male; Metagenomics; Microbiota; Oral Health; Paleodontology; Periodontitis; Rural Population
PubMed: 29768437
DOI: 10.1371/journal.pone.0196482 -
Advances in Dental Research Feb 2018A genome-wide transcriptional analysis was performed to elucidate the bacterial cellular response of Streptococcus mutans and Actinomyces viscosus to NaF and SnF. The...
A genome-wide transcriptional analysis was performed to elucidate the bacterial cellular response of Streptococcus mutans and Actinomyces viscosus to NaF and SnF. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of SnF were predetermined before microarray study. Gene expression profiling microarray experiments were carried out in the absence (control) and presence (experimental) of 10 ppm and 100 ppm Sn (in the form of SnF) and fluoride controls for 10-min exposures (4 biological replicates/treatment). These Sn levels and treatment time were chosen because they have been shown to slow bacterial growth of S. mutans (10 ppm) and A. viscosus (100 ppm) without affecting cell viability. All data generated by microarray experiments were analyzed with bioinformatics tools by applying the following criteria: 1) a q value should be ≤0.05, and 2) an absolute fold change in transcript level should be ≥1.5. Microarray results showed SnF significantly inhibited several genes encoding enzymes of the galactose pathway upon a 10-min exposure versus a negative control: lacA and lacB (A and B subunits of the galactose-6-P isomerase), lacC (tagatose-6-P kinase), lacD (tagatose-1,6-bP adolase), galK (galactokinase), galT (galactose-1-phosphate uridylyltransferase), and galE (UDP-glucose 4-epimerase). A gene fruK encoding fructose-1-phosphate kinase in the fructose pathway was also significantly inhibited. Several genes encoding fructose/mannose-specific enzyme IIABC components in the phosphotransferase system (PTS) were also downregulated, as was ldh encoding lactate dehydrogenase, a key enzyme involved in lactic acid synthesis. SnF downregulated the transcription of most key enzyme genes involved in the galactose pathway and also suppressed several key genes involved in the PTS, which transports sugars into the cell in the first step of glycolysis.
Topics: Actinomyces viscosus; Gene Expression Profiling; Genes, Bacterial; Microarray Analysis; Microbial Sensitivity Tests; RNA, Messenger; Sodium Fluoride; Streptococcus mutans; Tin Fluorides
PubMed: 29355427
DOI: 10.1177/0022034517737027 -
Journal of Oral Microbiology 2017The bovine milk protein osteopontin (OPN) may be an efficient means to prevent bacterial adhesion to dental tissues and control biofilm formation. This study sought to...
The bovine milk protein osteopontin (OPN) may be an efficient means to prevent bacterial adhesion to dental tissues and control biofilm formation. This study sought to determine to what extent OPN impacts adhesion forces and surface attachment of different bacterial strains involved in dental caries or medical device-related infections. It further investigated if OPN's effect on adhesion is caused by blocking the accessibility of glycoconjugates on bacterial surfaces. Bacterial adhesion was determined in a shear-controlled flow cell system in the presence of different concentrations of OPN, and interaction forces of single bacteria were quantified using single-cell force spectroscopy before and after OPN exposure. Moreover, the study investigated OPN's effect on the accessibility of cell surface glycoconjugates through fluorescence lectin-binding analysis. OPN strongly affected bacterial adhesion in a dose-dependent manner for all investigated species (, , subsp. , , , and ). Likewise, adhesion forces decreased after OPN treatment. No effect of OPN on the lectin-accessibility to glycoconjugates was found. OPN reduces the adhesion and adhesion force/energy of a variety of bacteria and has a potential therapeutic use for biofilm control. OPN acts upon bacterial adhesion without blocking cell surface glycoconjugates.
PubMed: 29081915
DOI: 10.1080/20002297.2017.1379826 -
European Journal of Oral Sciences Dec 2017The aim of this study was to evaluate the antimicrobial effects of non-thermal plasma-activated water (PAW) as a novel mouthwash in vitro. Three representative oral...
The aim of this study was to evaluate the antimicrobial effects of non-thermal plasma-activated water (PAW) as a novel mouthwash in vitro. Three representative oral pathogens - Streptococcus mutans, Actinomyces viscosus and Porphyromonas gingivalis - were treated with PAW. The inactivation effect was evaluated using the colony-forming unit (CFU) method, and the morphological and structural changes of a cell were observed by scanning electron microscopy and transmission electron microscopy (TEM). The physicochemical properties of PAW were analysed, and its influence on the leakage of intracellular proteins and DNA was evaluated. The results showed significant reduction of Streptococcus mutans within 60 s, of Actinomyces viscosus within 40 s, and of Porphyromonas gingivalis in less than 40 s. Scanning electron microscopy and TEM images showed that the normal cell morphology changed by varying degrees after treatment with PAW. Intracellular proteins (280 nm) and DNA (260 nm) leaked from all three species of bacteria after treatment with PAW. Reactive oxygen species (ROS), especially atomic oxygen (O), hydroxyl radical (˙OH), and hydrogen peroxide (H O ), were generated and led to strong oxidative stress and cell damage. These results suggest that PAW has potential use as a novel antimicrobial mouthwash.
Topics: Actinomyces viscosus; Anti-Bacterial Agents; Colony Count, Microbial; In Vitro Techniques; Microscopy, Electron; Mouth; Mouthwashes; Oxidative Stress; Plasma Gases; Porphyromonas gingivalis; Spectrum Analysis; Streptococcus mutans; Water
PubMed: 29024061
DOI: 10.1111/eos.12374 -
Nefrologia : Publicacion Oficial de La... 2017
PubMed: 28750877
DOI: 10.1016/j.nefro.2017.01.001 -
PloS One 2017Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome...
Dental caries is the most prevalent disease in humans globally. Efforts to control it have been invigorated by an increasing knowledge of the oral microbiome composition. This study aimed to evaluate the bacterial diversity in occlusal biofilms and its relationship with clinical surface diagnosis and dietary habits. Anamneses were recorded from thirteen 12-year-old children. Biofilm samples collected from occlusal surfaces of 46 permanent second molars were analyzed by 16S rRNA amplicon sequencing combined with the BLASTN-based search algorithm for species identification. The overall mean decayed, missing and filled surfaces modified index [DMFSm Index, including active white spot lesions (AWSL)] value was 8.77±7.47. Biofilm communities were highly polymicrobial collectively, representing 10 bacterial phyla, 25 classes, 29 orders, 58 families, 107 genera, 723 species. Streptococcus sp_Oral_Taxon_065, Corynebacterium matruchotii, Actinomyces viscosus, Actinomyces sp_Oral_Taxon_175, Actinomyces sp_Oral_Taxon_178, Actinomyces sp_Oral_Taxon_877, Prevotella nigrescens, Dialister micraerophilus, Eubacterium_XI G 1 infirmum were more abundant among surfaces with AWSL, and Streptococcus gordonii, Streptococcus sp._Oral_Taxon_058, Enterobacter sp._str._638 Streptococcus australis, Yersinia mollaretii, Enterobacter cloacae, Streptococcus sp._Oral_Taxon_71, Streptococcus sp._Oral_Taxon_F11, Centipeda sp._Oral_Taxon_D18 were more abundant among sound surfaces. Streptococcus mutans was detected on all surfaces in all patients, while Streptococcus sobrinus was detected only in three patients (mean relative abundances 7.1% and 0.6%, respectively). Neither species differentiated healthy from diseased sites. Diets of nine of the subjects were scored as high in fermentable carbohydrates (≧2X/day between meals). A direct association between relative abundances of bacteria and carbohydrate consumption was observed among 18 species. High consumption of fermentable carbohydrates and sound surfaces were associated with a reduction in bacterial diversity. PCoA plots displayed differences in bacterial community profiles between sound and diseased surfaces. Our study showed that, in addition to mutans streptococci, other species may be associated with the initiation of dental caries on occlusal surfaces, and that biofilm diversity of tooth surfaces is influenced by carbohydrate consumption and a surface's health status.
Topics: Bacteria; Brazil; Child; Cross-Sectional Studies; Dental Caries; Diet; Female; Humans; Male; Microbiota; Mouth; Surface Properties
PubMed: 28678838
DOI: 10.1371/journal.pone.0180621 -
Journal of Medical Microbiology Jun 2017Under certain circumstances, Actinomyces behaves as an opportunistic microorganism and can cause actinomycosis, a chronic and inflammatory granulomatous infection. The...
PURPOSE
Under certain circumstances, Actinomyces behaves as an opportunistic microorganism and can cause actinomycosis, a chronic and inflammatory granulomatous infection. The purpose of this project was to detect the presence of Actinomyces in cervical exudates from women with cervical intraepithelial neoplasia (CIN) and women with cervical cancer.
METHODOLOGY
Cervical samples from 92 women were divided into three groups: CIN, cervical cancer and healthy women. Metagenomic DNA extraction was performed following the Qiagen QIAamp Mini Kit protocol. A specific fragment (675 bp) was amplified by PCR in order to detect the presence of Actinomycetales. Samples in which Actinomycetales was detected were subjected to separate amplification reactions with primer pairs for A. israelii, A. viscosus, A. meyeri and A. odontolyticus. Amplified products were observed by 2 % agarose gel electrophoresis.
RESULTS
Actinomyces were found in 10 % of women with CIN, 36.6 % of women with cervical cancer and 9 % of healthy women. The species identified in this study were A. meyeri in 14/92 samples (15.2 %), A. viscosus in 10/92 samples (10.8 %), A. odontolyticus in 4/92 samples (4.3 %) and A. israelii in 6/92 samples (6.5 %).
CONCLUSION
Patients with cervical cancer had a higher prevalence of the presence of Actinomyces compared to the CIN and control groups. This is the first study in which a deliberate search of this genus has been performed in women with cervical pathologies. The use of specific primers for each species facilitated their detection in comparison with traditional isolation methods. More information is necessary to understand the molecular mechanisms involved in the complex role that bacterial communities may play in the development of cancer (and vice versa).
Topics: Actinomyces; Actinomycosis; Adult; Cervix Uteri; Cross-Sectional Studies; Female; Genotype; Healthy Volunteers; Humans; Metagenomics; Middle Aged; Polymerase Chain Reaction; Prevalence; Uterine Cervical Neoplasms; Young Adult; Uterine Cervical Dysplasia
PubMed: 28590243
DOI: 10.1099/jmm.0.000485