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Microorganisms Oct 2021This study evaluated the microbial colonization (adhesion and biofilm) on modified surfaces of a titanium alloy, Ti-35Nb-7Zr-5Ta, anodized with Ca and P or F ions, with...
This study evaluated the microbial colonization (adhesion and biofilm) on modified surfaces of a titanium alloy, Ti-35Nb-7Zr-5Ta, anodized with Ca and P or F ions, with and without silver deposition. The chemical composition, surface topography, roughness (Ra), and surface free energy were evaluated before and after the surface modifications (anodizing). Adhesion and biofilm formation on saliva-coated discs by primary colonizing species (, , ) and a periodontal pathogen () were assessed. The surfaces of titanium alloys were modified after anodizing with volcano-shaped micropores with Ca and P or nanosized with F, both with further silver deposition. There was an increase in the Ra values after micropores formation; CaP surfaces became more hydrophilic than other surfaces, showing the highest polar component. For adhesion, no difference was detected for on all surfaces, and some differences were observed for the other three species. No differences were found for biofilm formation per species on all surfaces. However, biofilm counts on distinct surfaces were lower than , , and on some surfaces. Therefore, anodized Ti-35Nb-7Zr-5Ta affected microbial adhesion and subsequent biofilm, but silver deposition did not hinder the colonization of these microorganisms.
PubMed: 34683474
DOI: 10.3390/microorganisms9102154 -
The American Journal of Pathology Mar 1983The histopathologic features of experimental actinomycotic lesions produced in mice by Actinomyces israelii, Actinomyces naeslundii, and Actinomyces viscosus were... (Comparative Study)
Comparative Study
The histopathologic features of experimental actinomycotic lesions produced in mice by Actinomyces israelii, Actinomyces naeslundii, and Actinomyces viscosus were examined. In lesions caused by A israelii the outer edge of the bacterial granule exhibited an eosinophilic fringe with no evidence of penetration of polymorphonuclear leukocytes (PMNs) into the bacterial granule. Chronic lesions after 6 weeks contained lobulated advancing fronts as well as areas of resolution showing heavy penetration by phagocytic cells. The number of macrophages and plasma cells in these lesions increased with time. In contrast, lesions caused by A viscosus and A naeslundii showed cellular evidence of resolution during the early stages of the infection (3-6 weeks). The bacterial core was readily penetrated and fragmented by PMNs in early A viscosus lesions. In lesions caused by A naeslundii there was less penetration of the central core by PMNs, and the bacterial granule tended to retain its structural integrity. Elongated crystals of hyaloid material appeared in lesions caused by all species. These protein-rich bodies appeared to be associated with resolving areas of the lesions. The observed contrast in the histopathologic appearance of actinomycotic lesions caused by A israelii, A naeslundii, and A viscosus is suggestive of important differences in the immune response of the host to infections caused by these three species.
Topics: Actinomyces; Actinomycosis; Animals; Granulocytes; Male; Mice; Species Specificity
PubMed: 6829706
DOI: No ID Found -
Clinical Oral Investigations Oct 2023The present study aimed to evaluate the potential of the salivary pellicle (SP) formed on titanium (Ti) surfaces to modulate the formation of a biofilm composed of...
OBJECTIVES
The present study aimed to evaluate the potential of the salivary pellicle (SP) formed on titanium (Ti) surfaces to modulate the formation of a biofilm composed of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis.
MATERIALS AND METHODS
Ti substrates were incubated for 2 h with a pool of saliva samples obtained from 10 systemically and periodontally healthy subjects. Enamel substrates were included as a biological reference. Scanning electron microscopy (SEM) and Raman spectroscopy analysis were used to analyze the formation of the salivary pellicle. After the SP formation, the surfaces were incubated for 12 h with a mix of Streptococcus gordonii, Actinomyces naeslundii, Fusobacterium nucleatum, and Porphyromonas gingivalis. The number of bacterial cells attached to each surface was determined by the XTT assay while bacterial viability was analyzed by fluorescence microscopy using the LIVE/DEAD® BacLight kit.
RESULTS
The SEM and Raman spectroscopy analysis confirmed the presence of a salivary pellicle formed on the tested surfaces. Regarding the biofilm formation, the presence of the SP decreases the number of the bacterial cells detected in the test surfaces, compared with the uncover substrates. Even more, the SP-covered substrates showed similar bacterial counts in both Ti and enamel surfaces, meaning that the physicochemical differences of the substrates were less determinant than the presence of the SP. While on the SP-uncover substrates, differences in the bacterial adhesion patterns were directly related to the physicochemical nature of the substrates.
CONCLUSIONS
The salivary pellicle was the main modulator in the development of the biofilm consisting of representative oral bacteria on the Ti substrates.
CLINICAL RELEVANCE
The results of this study provide valuable information on the modulatory effect of the salivary pellicle on biofilm formation; such information allows us to understand better the events involved in the formation of oral biofilms on Ti dental implants.
Topics: Humans; Dental Pellicle; Titanium; Biofilms; Bacterial Adhesion; Streptococcus gordonii; Fusobacterium nucleatum; Surface Properties
PubMed: 37646908
DOI: 10.1007/s00784-023-05230-9 -
Dental Materials Journal Jan 2021Zinc-fluoride glass nanoparticles (Zinc-F) release several ions, such as fluoride, zinc and calcium ions, through acid-base reactions. The aim of this study was to...
Zinc-fluoride glass nanoparticles (Zinc-F) release several ions, such as fluoride, zinc and calcium ions, through acid-base reactions. The aim of this study was to evaluate the antibacterial and cytotoxic properties of Zinc-F. Antibacterial tests showed that a Zinc-F eluting solution significantly reduced the turbidity and colony-forming units of Streptococcus mutans and Actinomyces naeslundii, compared to that of calcium-fluoroaluminosilicate glass nanoparticles without zinc ions. In live/dead staining, Zinc-F eluate significantly decreased green-stained bacterial cells, indicating live cells, compared with the control (no application). Human dentin coated with Zinc-F showed suppressed S. mutans and A. naeslundii biofilm formation. Additionally, Zinc-F eluate showed low cytotoxic effects in osteoblastic and fibroblastic cells. Therefore, our findings suggested that Zinc-F exhibits antibacterial and biocompatible properties through multiple-ion release.
Topics: Actinomyces; Anti-Bacterial Agents; Biofilms; Fluorides; Humans; Nanoparticles; Streptococcus mutans; Zinc
PubMed: 32999216
DOI: 10.4012/dmj.2019-176 -
Infection and Immunity Dec 1974Whole cells of Actinomyces naeslundii ATCC 12104, either in a dispersed form or in the form of plaque, enzymatically degraded sucrose to glucose and fructose. Washed...
Whole cells of Actinomyces naeslundii ATCC 12104, either in a dispersed form or in the form of plaque, enzymatically degraded sucrose to glucose and fructose. Washed whole cells expressed beta-fructofuranosidase specificity and hydrolyzed sucrose to essentially equimolar quantities of glucose and fructose. The cells readily hydrolyzed sucrose, raffinose, and Actinomyces viscosus or Aerobacter levanicum levan, but did not degrade melezitose, maltose, alpha-methyl-d-glucoside, melibiose, glucose-1-phosphate, or dextran T-500. Sucrose degradation occurred at a temperature optimum of 37 to 45 C and at a pH optimum of 5.7 to 6.0. The K(m) for sucrose was 0.05 M. Sucrose or raffinose in the growth medium resulted in cells with a specific activity that was fivefold greater than that of cells grown in medium supplemented with either glucose, fructose, maltose, lactose, or glucose and fructose, or grown in unsupplemented medium. Addition of sucrose to log-phase cells growing in glucose also increased the specific activity. Degradation of sucrose by whole cells in the form of plaque also occurred, but 6% less free fructose than free glucose was recovered. Sucrose-dependent synthesis of extracellular levan or glucan by whole cells or plaque could not be demonstrated. The ability of A. naeslundii to degrade sucrose and levan may be related to the pathogenic potential of this bacterium in plaque-associated oral diseases.
Topics: Actinomyces; Bacteriological Techniques; Carbohydrates; Chromatography, Thin Layer; Culture Media; Fructose; Glucose; Hexoses; Hydrogen-Ion Concentration; Hydrolysis; Kinetics; Polysaccharides; Sucrose; Temperature; Viral Plaque Assay
PubMed: 4611924
DOI: 10.1128/iai.10.6.1280-1291.1974 -
IDCases 2020Pott's puffy tumor is characterized by forehead swelling from subperiosteal abscess and frontal bone osteomyelitis. It is encountered mainly in children; rarely in...
Pott's puffy tumor is characterized by forehead swelling from subperiosteal abscess and frontal bone osteomyelitis. It is encountered mainly in children; rarely in adults. When it does occur in the latter population, the most common risk factors include head trauma, sinusitis, or cocaine abuse. Generally, the organisms thought to be involved include streptococci, staphylococci and oral anaerobic flora. We present a case of a 53 year old female who presented with forehead swelling of 3 month duration after a dental procedure, found to be secondary to . Actinomyces is a very rare etiology of this disease and has been reported only twice earlier in the literature. We present an uncommon infectious disease along with summary of clinical characteristics of this entity in the adult population.
PubMed: 33033689
DOI: 10.1016/j.idcr.2020.e00974 -
Infection and Immunity Jul 1997The nucleotide sequence of the chromosomal DNA flanking the Actinomyces naeslundii (formerly A. viscosus) T14V type 1 fimbrial structural subunit gene (fimP) was...
The nucleotide sequence of the chromosomal DNA flanking the Actinomyces naeslundii (formerly A. viscosus) T14V type 1 fimbrial structural subunit gene (fimP) was determined. Six open reading frames (ORFs), in the order 5' ORF3, ORF2, ORF1,fimP, ORF4, ORF5, ORF6 3', were identified. ORF1 encoded a protein of 408 amino acid residues (Mr = 39,270) and had significant sequence homology with the A. naeslundii T14V type 1 and A. naeslundii WVU45 type 2 fimbrial structural subunits. An in-frame fusion of ORF1 to the malE gene of the expression vector, pMAL-c2, yielded a protein that was immunostained with antibodies raised against the maltose binding protein and A. naeslundii T14V whole bacteria. Digestion of the fusion protein with factor Xa released a protein (apparent molecular mass of 34 kDa) that was immunostained only with the antibody directed against A. naeslundii T14V whole bacterial cells. Integration plasmids carrying a kanamycin resistance gene (kan) that was used to substitute for ORF1 or for DNA fragments internal to the coding region of the other five ORFs were used to transform A. naeslundii T14V. Neither type 1 fimbriae nor the 65-kDa fimbrial structural subunit was detected in mutants obtained by allelic replacement of ORF1 or ORF2. Mutants obtained by allelic replacement of ORF3 or ORF4 expressed only the 65-kDa fimbrial structural subunit. These mutants did not bind, in vitro, to proline-rich proteins that serve as the receptors for Actinomyces type 1 fimbriae. In contrast, a mutant in which the integration plasmid DNA had been inserted at a site close to the carboxyl terminus of ORF6 expressed type 1 fimbriae and had adherence properties similar to those observed in the wild-type strain. These results demonstrate the existence of additional genes near fimP that are likely to be involved in the synthesis and function of cell surface fimbriae of A. naeslundii T14V.
Topics: Actinomyces viscosus; Amino Acid Sequence; Bacterial Proteins; Base Sequence; DNA, Bacterial; Fimbriae, Bacterial; Genes, Bacterial; Kanamycin Resistance; Molecular Sequence Data; Open Reading Frames
PubMed: 9199430
DOI: 10.1128/iai.65.7.2629-2639.1997 -
Journal of Oral Microbiology 2022Biofilm formation under cariogenic conditions contributes to dental caries development, in which () is regarded as the major cariogenic bacteria. Here, we synthesized a...
OBJECTIVE
Biofilm formation under cariogenic conditions contributes to dental caries development, in which () is regarded as the major cariogenic bacteria. Here, we synthesized a series of imidazolium salts. Their properties of antimicrobial and anti-biofilm were investigated.
METHODS
The microdilution method crystal violet staining, and cell counting Kit-8 assay were used to screen imidazolium salts. Then, the bacterial composition in multi-species biofilm composed of and was quantified by quantitative PCR. The exopolysaccharide and morphology of the structure of multi-species biofilm were further observed by confocal laser scanning microscopy and scanning electron microscope, respectively.
RESULTS
Imidazolium salts exhibited highly antimicrobial activity against oral pathogens, especially for . Compounds with -diisopropyl and -methoxyl on N-moieties as well as bearing ancenaphthyl skeleton (C5) showed the lowest cytotoxicity and most efficient anti-biofilm activity. C5 inhibited approximately 50% of multi-species biofilm at 0.98 μg/mL. Notably, C5 resulted in 98.97% live and 77.65% decreased. Furthermore, the exopolysaccharide was reduced by 88%, along with a sparse and scattered microstructure.
CONCLUSION
The imidazolium salts present low cytotoxicity and remarkable antimicrobial activity against in multi-species biofilm, suggesting that they may have a great potential in anti-biofilm clinical applications.
PubMed: 35600163
DOI: 10.1080/20002297.2022.2075309 -
Case Reports in Infectious Diseases 2015Actinomyces rarely causes endocarditis with 25 well-described cases reported in the literature in the past 75 years. We present a case of prosthetic valve endocarditis...
Actinomyces rarely causes endocarditis with 25 well-described cases reported in the literature in the past 75 years. We present a case of prosthetic valve endocarditis (PVE) caused by Actinomyces naeslundii. To our knowledge, this is the first report in the literature of endocarditis due to this organism and the second report of PVE caused by Actinomyces.
PubMed: 26697243
DOI: 10.1155/2015/602462 -
Infection and Immunity Dec 2001The initial stages of dental plaque formation involve the adherence of early colonizing organisms such as Streptococcus gordonii and Actinomyces naeslundii to the...
The initial stages of dental plaque formation involve the adherence of early colonizing organisms such as Streptococcus gordonii and Actinomyces naeslundii to the saliva-coated tooth surface and to each other. The S. gordonii surface proteins SspA and SspB are known to play a role in adherence to salivary proteins and mediate coaggregation with other bacteria. Coaggregation is the adhesin receptor-mediated interaction between genetically distinct cell types and appears to be ubiquitous among oral isolates. To define the function of SspA and SspB separately on the surface of their natural host, we constructed and analyzed the coaggregation properties of an isogenic sspB mutant of S. gordonii DL1, an sspAB double mutant, and a previously described sspA mutant. A. naeslundii strains have been previously classified into six coaggregation groups based on the nature of their coaggregations with S. gordonii DL1 and other oral streptococci. Coaggregation assays with the sspA and sspB mutants showed that SspA and SspB are the streptococcal proteins primarily responsible for defining these coaggregation groups and, thus, are highly significant in the establishment of early dental plaque. SspA exhibited two coaggregation-specific functions. It participated in lactose-inhibitable and -noninhibitable interactions, while SspB mediated only lactose-noninhibitable coaggregations. Accordingly, the sspAB double mutant lacked these functions and allowed us to detect a third coaggregation interaction with one of these organisms. These proteins may play an important role in development of S. gordonii-A. naeslundii communities in early dental plaque. Understanding these adhesin proteins will aid investigations of complex microbial communities that characterize periodontal diseases.
Topics: Actinomyces; Adhesins, Bacterial; Bacterial Adhesion; Dental Plaque; Ecology; Humans; Lectins; Mutation; Protein Binding; Streptococcus
PubMed: 11705927
DOI: 10.1128/IAI.69.12.7512-7516.2001