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The Journal of Pediatrics Nov 1978
Topics: Actinomycosis, Cervicofacial; Child; Humans; Male; Pharyngeal Diseases; Thyroid Diseases
PubMed: 712485
DOI: 10.1016/s0022-3476(78)81082-8 -
Journal of Clinical Microbiology Jun 1978Metronidazole (10 microgram/ml) and cadmium sulfate (20 microgram/ml) were added to a gelatin-based medium to select for microaerophilic Actinomyces species from dental... (Comparative Study)
Comparative Study
Metronidazole (10 microgram/ml) and cadmium sulfate (20 microgram/ml) were added to a gelatin-based medium to select for microaerophilic Actinomyces species from dental plaque samples. The new medium (GMC), when incubated anaerobically, allowed 98% recovery of seven pure cultures of Actinomyces viscosus and 73% recovery of eight pure cultures of Actinomyces naeslundii, while suppressing 76% of the total count of other organisms in dental plaque samples. In 203 plaque samples, recoveries of A. viscosus and A. naeslundii on GMC and another selective medium for oral Actinomyces (CNAC-20) were compared. Recovery of A. viscosus was comparable on the two media. Recovery of A. naeslundii was significantly higher on GMC than CNAC-20 (P is less than 0.001), and GMC allowed a more characteristic cell morphology of both organisms. GMC medium appears to be useful for the isolation and presumptive identification of A. viscosus and A. naeslundii from dental plaque.
Topics: Actinomyces; Cadmium; Culture Media; Dental Plaque; Humans; Kanamycin; Metronidazole
PubMed: 670376
DOI: 10.1128/jcm.7.6.514-518.1978 -
Journal of Bone and Joint Infection 2020is an oral bacterium that is rarely virulent in humans, with most case presentations involving dental and maxillofacial infections. We describe the first reported case...
is an oral bacterium that is rarely virulent in humans, with most case presentations involving dental and maxillofacial infections. We describe the first reported case of vertebral osteomyelitis in a patient who had a significant response to penicillin after minimal response to cephalosporin therapy.
PubMed: 32983847
DOI: 10.5194/jbji-6-39-2020 -
The Journal of Infection May 2005We report a case of primary Actinomyces viscosus endocarditis, an unusual manifestation of actinomycosis, in a 43-year-old farmer with an indolent febrile illness. As...
We report a case of primary Actinomyces viscosus endocarditis, an unusual manifestation of actinomycosis, in a 43-year-old farmer with an indolent febrile illness. As has occurred in previous cases, diagnosis was delayed in part because blood isolates were misidentified. Months later when she required aortic valve and root replacement, histologic exam of the diseased valve revealed branching filamentous organisms and the original blood isolates were retrospectively confirmed to be Actinomyces viscosus.
Topics: Actinomyces viscosus; Actinomycosis; Adult; Aortic Valve; Endocarditis, Bacterial; Female; Humans
PubMed: 15845438
DOI: 10.1016/j.jinf.2004.04.006 -
Journal - Connecticut State Dental... 1979
Review
Topics: Actinomyces; Animals; Carbohydrate Metabolism; Dental Caries; Humans; Periodontal Diseases
PubMed: 121304
DOI: No ID Found -
Archives of Oral Biology Apr 2019How the interactions between Candida albicans and Actinomyces viscosus contributed to the root caries was not clear. This study aimed to investigate their cross-kingdom...
OBJECTIVE
How the interactions between Candida albicans and Actinomyces viscosus contributed to the root caries was not clear. This study aimed to investigate their cross-kingdom interactions on the biomass and the cariogenic virulence in dual-species biofilms.
DESIGN
Suspensions of C. albicans and A. viscosus were formed the mono and polymicrobial biofilms in vitro. Crystal violet assay, viable plate count, scanning electron microscopy and fluorescence in situ hybridization were used to analyze the biomass and biofilm structure. Glycolytic pH drop and the spectrophotometric method were used to evaluate the acid production and hydroxyapatite dissolution, respectively. The exopolysaccharide production was measured by the anthrone-sulfuric acid method, while the adhesion force was measured by atomic force microscopy.
RESULTS
The biomass and colony-forming units of mixed-species were significantly increased compared to that of the mono-species at 24 h, 48 h, 72 h. The structure of dual-species biofilm had more microcolonies and was much denser. The dual-species biofilms significantly decreased the pH value and damaged the hydroxyapatite compared with the mono-species biofilms at various time points, indicating the strong cariogenic virulence. Moreover, the dual-species biofilms significantly enhanced the exopolysaccharide production and adhesion force suggesting the increase of biofilm adhesion.
CONCLUSIONS
Cross-kingdom interactions of C. albicans and A. viscosus significantly elevated the biomass and cariogenic virulence of dual-species biofilm.
Topics: Actinomyces viscosus; Biofilms; Candida albicans; Dental Caries; In Situ Hybridization, Fluorescence; Microbial Interactions; Virulence
PubMed: 30822704
DOI: 10.1016/j.archoralbio.2019.02.008 -
Infection and Immunity Oct 1978Actinomyces viscosus ATCC 15987 was examined for its ability to hydrolyze its own levan. Washed whole cells and an ammonium sulfate fraction from cell-free culture...
Actinomyces viscosus ATCC 15987 was examined for its ability to hydrolyze its own levan. Washed whole cells and an ammonium sulfate fraction from cell-free culture fluids were shown to possess levan hydrolase activity. Analyses of reaction mixtures by gel filtration and thin-layer chromatography demonstrated that the product of levan hydrolysis was free fructose. The cell-associated and extracellular enzyme preparations also hydrolyzed inulin and the levans synthesized by Aerobacter levanicum and Bacillus subtilis. Growth of A. viscosus in media supplemented with 0.1% A. viscosus levan resulted in a 33-fold increase and a 7-fold increase in the specific activities of the respective extracellular and cell-associated enzymes when compared with those from 55 mM glucose cultures. Growth in the presence of 29.2 mM sucrose resulted in a 28-fold increase and a 5-fold increase in the specific activities of the respective enzymes when compared with those from the glucose cultures. The extracellular enzyme exhibited high activity over a wide pH range, with 87 and 89% of its pH 6.0 optimum activity at pH 5.0 and 7.0, respectively. The cell-associated enzyme also exhibited optimum activity at pH 6.0, but this was decreased to 10 and 20% at pH 5.0 and 7.0, respectively. Analysis for the presence of extracellular levan during growth of A. viscosus in sucrose broths demonstrated that peak levan concentrations occurred during the mid-exponential to late-exponential phase of growth followed by a rapid decline in extracellular levan as a result of levan hydrolase activity.
Topics: Actinomyces; Fructans; Fructose; Hydrogen-Ion Concentration; Hydrolases; Inulin; Kinetics; Polysaccharides; Polysaccharides, Bacterial
PubMed: 32137
DOI: 10.1128/iai.22.1.266-274.1978 -
International Journal of Antimicrobial... Jun 2019Candida albicans and Actinomyces viscosus are prominent microbes associated with dental root caries. The aim of this study was to investigate the effect of C. albicans...
Candida albicans and Actinomyces viscosus are prominent microbes associated with dental root caries. The aim of this study was to investigate the effect of C. albicans on A. viscosus biofilms and to identify the mechanisms associated with this interaction. A. viscosus and C. albicans strains (wide-type and mutants) were used to form biofilms in vitro and in vivo, which were subsequently analysed by crystal violet assay and scanning electron microscopy (SEM) to investigate the effect of C. albicans on A. viscosus growth. A viable plate count and survival curve for C. albicans mutants and A. viscosus combinations were used to identify which C. albicans pathway was crucial for cross-kingdom interactions. Voriconazole was used to block their interactions both in vitro and in vivo. SEM, fluorescence in situ hybridisation (FISH), quantitative PCR and survival curve analyses were performed to evaluate the activity of voriconazole on C. albicans and A. viscosus interactions. The biomass and virulence of mixed-species biofilms were significantly enhanced compared with the A. viscosus biofilm alone. However, this was not observed in the mixed-species biofilms with the C. albicans mutant erg11Δ/Δ in vitro and in vivo, indicating that azoles may work on the mixed-species biofilms. As expected, voriconazole can effectively reduce the biomass of mixed-species biofilms. A high concentration of voriconazole (1 µg/mL) reduced the abundance of C. albicans, whilst a low voriconazole concentration (0.25 µg/mL) blocked their interactions similar to the effect of the erg11Δ/Δ mutant. Voriconazole may be a candidate strategy to combat root caries pathogens.
Topics: Actinomyces viscosus; Animals; Antifungal Agents; Biofilms; Candida albicans; Ergosterol; Gentian Violet; Humans; In Situ Hybridization, Fluorescence; Metabolic Networks and Pathways; Microbial Interactions; Microbial Viability; Microscopy, Electron, Scanning; Provitamins; Staining and Labeling; Voriconazole
PubMed: 30818001
DOI: 10.1016/j.ijantimicag.2019.02.010 -
Oral Microbiology and Immunology Aug 1990Actinomyces viscosus and Actinomyces naeslundii were grown in chemostat cultures with glucose or lactate as the sole sources of energy. Growth on lactate was dependent... (Comparative Study)
Comparative Study
Actinomyces viscosus and Actinomyces naeslundii were grown in chemostat cultures with glucose or lactate as the sole sources of energy. Growth on lactate was dependent on oxygen. Lactate was oxidised partly to acetic acid. As judged from the low carbon recoveries in acidic degradation products, it is concluded that a substantial part of the lactate was oxidised to carbon dioxide. Assuming that 1 ATP is generated in the transfer of an electron pair to oxygen, YATP values of 10-11 were calculated from the molar growth yield on lactate and product formation. Although all cell 3 test strains oxidised lactate, one strain could not grow on lactate as the sole source of energy. The rate of oxygen uptake with lactate as substrate was higher for cells grown aerobically than of cells grown anaerobically, indicating that lactate oxidation was induced by oxygen. It is reasonable to assume that lactate oxidation is mediated either by lactate dehydrogenase or lactate oxidase, but the pathway in Actinomyces sp. is not yet known. Lactate consumption may be an important trait of Actinomyces sp. that live in an environment limited in energy sources for most of the time.
Topics: Actinomyces; Aerobiosis; Anaerobiosis; Ecology; Electron Transport; Glucose; Lactates; Oxidative Phosphorylation; Oxygen
PubMed: 2082247
DOI: 10.1111/j.1399-302x.1990.tb00650.x -
Infection and Immunity Nov 1976The intraoral establishment and proportional distribution of suspected periodontal pathogens Actinomyces viscosus and Actinomyces naeslundii were studied using a...
The intraoral establishment and proportional distribution of suspected periodontal pathogens Actinomyces viscosus and Actinomyces naeslundii were studied using a recently developed differential plating medium, CNAC-20. Saliva and dental plaque samples were collected from 108 subjects ranging in age from infants to young adults; tongue and buccal mucosa samples were collected from only the adult subjects. Catalase-negative A. naeslundii was isolated from 40% of the predentate infants' and almost all other subjects' saliva samples. It predominated among CNAC-20 isolates in the saliva of subjects of all age groups, in the plaques of young children, and in the adult tongue samples. In contrast, catalase-positive A. viscosus was not isolated from predentate infant samples, and its frequency of isolation increased slowly with age (greater than 50% detection by age 7). A. viscosus was isolated in highest relative proportions from dental plaque and buccal mucosa samples. The two closely related species A. viscosus and A. naeslundii apparently differ in respect to factors determining the host age at which they colonize and their relative intraoral distribution in humans.
Topics: Actinomyces; Adolescent; Adult; Anaerobiosis; Child; Child, Preschool; Dental Plaque; Humans; Infant; Mouth; Mouth Mucosa; Saliva; Tongue
PubMed: 977124
DOI: 10.1128/iai.14.5.1119-1124.1976