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Revista Argentina de Microbiologia 2021Actinomyces and related genera are grampositive bacilli, opportunistic pathogens, which have been mainly involved in endogenous infections. However, due to the...
Actinomyces and related genera are grampositive bacilli, opportunistic pathogens, which have been mainly involved in endogenous infections. However, due to the complexity in identifying them for most clinical laboratories, there is scant knowledge about their real clinical significance. In this work, 166 isolates of 13 different species of Actinomyces/Actinotignum species recovered from clinical samples of patients treated in a university hospital were studied. The identification was performed by MALDI-TOF MS and molecular identification. MALDI-TOF MS identified 91.57% of the isolates (152/166) at the species level using a score ≥ 1.7 and 3.61% (6/166) of the isolates were identified only at the gender level with a score ≥ 1.5. MALDI-TOF MS did not yield reliable identification results for 4.82% (8/166) of the isolates. Actinomyces/Actinotignum species were isolated from: soft tissue (n: 47), urine samples (n: 35), head / neck abscesses (n: 19), genital abscesses (n: 11), blood samples (n: 10), breast abscesses (n: 8), osteoarticular samples (n: 6), abdominal/ascitic fluids (n: 3), abdominal abscesses (n: 5), sputum/BAL (n: 4), brain abscesses (n: 3), and others (n: 15). The results obtained from the statistical analysis showed a high differential frequency (> 2) for the location/species association: urine/A. schaalii/sanguinis; brain abscesses/A. europaeus; osteoarticular samples/A. urogenitalis; abdominal abscesses/ A. turicensis; respiratory samples/A. naeslundii/viscosus. This information provides a greater understanding of the clinical and epidemiological relevance of these species. The pathogenic role of Actinomyces spp. will be increasingly revealed as these microorganisms could be recognized thanks to prolonged culture and the advances in identification technology facilitated by MALDI-TOF MS.
Topics: Actinomyces; Actinomycetaceae; Hospitals; Humans; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 33402284
DOI: 10.1016/j.ram.2020.11.005 -
Special Care in Dentistry : Official... Jan 2021To analyze potential factors associated with levels of selected oral pathogens, as well as total aerobic bacterial species, among nursing home residents.
PURPOSE/AIM
To analyze potential factors associated with levels of selected oral pathogens, as well as total aerobic bacterial species, among nursing home residents.
MATERIALS AND METHODS
Nursing home residents were divided into three groups (G1 included people with teeth but no dentures, G2 included people with teeth and dentures, and G3 included people with no teeth and with dentures). All participants had microbiological samples collected from their oral cavity and dentures. Counts of total aerobic bacterial species, Porphyromonas gingivalis, Fusobacterium nucleatum, Actinomyces viscosus, Aggregatibacter actinomycetemcomitans, and Candida albicans were compared among groups using the Wilcoxon rank sum test. A multivariate analysis was also performed to control other available covariates.
RESULTS
Bivariate analysis revealed significant differences among the groups, and multivariate analysis showed that sex, the presence of natural teeth, denture wearing, oral hygiene indices, and systemic health conditions were associated with bacterial and Candida albicans log counts.
CONCLUSIONS
Presence of natural teeth and denture wearing, as well as oral hygiene, sex and systemic health conditions were associated with bacterial and Candida albicans log counts among nursing home residents.
Topics: Humans; Mouth, Edentulous; Nursing Homes; Oral Hygiene; Tooth
PubMed: 33075154
DOI: 10.1111/scd.12530 -
Diagnostics (Basel, Switzerland) Oct 2020This study aims to investigate and assess salivary biomarkers and microbial profiles as a means of diagnosing periodontitis. A total of 121 subjects were included: 28...
This study aims to investigate and assess salivary biomarkers and microbial profiles as a means of diagnosing periodontitis. A total of 121 subjects were included: 28 periodontally healthy subjects, 24 with Stage I periodontitis, 24 with Stage II, 23 with Stage III, and 22 with Stage IV. Salivary proteins (including active matrix metalloproteinase-8 (MMP-8), pro-MMP-8, total MMP-8, C-reactive protein, secretory immunoglobulin A) and planktonic bacteria (including , , , , , , , , , , , , , , and ) were measured from salivary samples. The performance of the diagnostic models was assessed by receiver operating characteristics (ROCs) and area under the ROC curve (AUC) analysis. The diagnostic models were constructed based on the subjects' proteins and/or microbial profiles, resulting in two potential diagnosis models that achieved better diagnostic powers, with an AUC value > 0.750 for the diagnosis of Stages II, III, and IV periodontitis (Model PA-I; AUC: 0.796, sensitivity: 0.754, specificity: 0.712) and for the diagnosis of Stages III and IV periodontitis (Model PA-II; AUC: 0.796, sensitivity: 0.756, specificity: 0.868). This study can contribute to screening for periodontitis based on salivary biomarkers.
PubMed: 33066545
DOI: 10.3390/diagnostics10100820 -
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 -
Journal of the Indian Society of... 2020Complete elimination of microorganisms from the root canals is the important key for the successful endodontic treatment. Constant emergence of resistant strains and...
BACKGROUND
Complete elimination of microorganisms from the root canals is the important key for the successful endodontic treatment. Constant emergence of resistant strains and adverse effects of synthetic drugs has led to the search of effective herbal alternatives. Nutmeg (Myristica fragrans) is one such spice used for its various medicinal activities.
AIMS
To evaluate the antimicrobial effect of M. fragrans on common endodontic pathogens of primary tooth.
MATERIALS AND METHODS
Essential oil of nutmeg was extracted by hydrodistillation method, and its phytoconstituents were determined by thin-layer chromatography (TLC), high-performance TLC, and gas chromatography-mass spectrometry analysis. Minimum inhibitory concentration of essential oil against standard strains of common endodontic pathogens (Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Candida albicans, Lactobacillus casei, Actinomyces viscosus, Prevotella intermedia, and Porphyromonas gingivalis) was determined by serial tube dilution method.
RESULTS
Essential oil of M. fragrans was effective against all tested endodontic microorganisms.
DISCUSSION
The active components of essential oil of nutmeg such as myristicin, myristic acid, trimyristin, elemicin, and safrole have good antimicrobial activity and are effective against endodontic microorganisms.
CONCLUSION
M. fragrans can be used as an effective medicament in the treatment of endodontic infections.
Topics: Anti-Infective Agents; Gas Chromatography-Mass Spectrometry; Myristica; Oils, Volatile; Seeds
PubMed: 32611860
DOI: 10.4103/JISPPD.JISPPD_214_20 -
Applied and Environmental Microbiology Aug 2020This study compares the metabolic properties of kojibiose, trehalose, sucrose, and xylitol upon incubation with representative oral bacteria as monocultures or synthetic...
This study compares the metabolic properties of kojibiose, trehalose, sucrose, and xylitol upon incubation with representative oral bacteria as monocultures or synthetic communities or with human salivary bacteria in a defined medium. Compared to sucrose and trehalose, kojibiose resisted metabolism during a 48-h incubation with monocultures, except for Incubations with -based communities, as well as salivary bacteria, displayed kojibiose metabolism, yet to a lesser extent than sucrose and trehalose. Concurring with our findings, screening for carbohydrate-active enzymes revealed that only spp. and possess enzymes from glycohydrolase (GH) families GH65 and GH15, respectively, which are associated with kojibiose metabolism. Donor-dependent differences in salivary microbiome composition were noted, and differences in pH drop during incubation indicated different rates of sugar metabolism. However, functional analysis indicated that lactate, acetate, and formate evenly dominated the metabolic profile for all sugars except for xylitol. 16S rRNA gene sequencing analysis and α-diversity markers revealed that a significant shift of the microbiome community by sugars was more pronounced in sucrose and trehalose than in kojibiose and xylitol. In spp., a taxon linked to cariogenesis dominated in sucrose (mean ± standard deviation, 91.8 ± 6.4%) and trehalose (55.9 ± 38.6%), representing a high diversity loss. In contrast, (5.1 ± 3.7%) was less abundant in kojibiose, which instead was dominated by (26.8 ± 19.6%), while for xylitol, (29.4 ± 19.1%) was most abundant. Overall, kojibiose and xylitol incubations stimulated cariogenic species less yet closely maintained an abundance of key phyla and genera of the salivary microbiome, suggesting that kojibiose has low cariogenic properties. This study provides a detailed scientific insight on the metabolism of a rare disaccharide, kojibiose, whose mass production has recently been made possible. While the resistance of kojibiose was established with monocultures, delayed utilization of kojibiose was observed with communities containing lactobacilli and as well as with complex communities of bacteria from human saliva. Kojibiose is, therefore, less metabolizable than sucrose and trehalose. Moreover, although conventional sugars cause distinct shifts in salivary microbial communities, our study has revealed that kojibiose is able to closely maintain the salivary microbiome composition, suggesting its low cariogenic properties. This study furthermore underscores the importance and relevance of microbial culture and mixed cultures to study cariogenicity and substrate utilization; this is in sharp contrast with tests that solely rely on monocultures such as , which clearly fail to capture complex interactions between oral microbiota.
Topics: Bacteria; Disaccharides; Humans; Kinetics; Microbiota; Mouth; RNA, Bacterial; RNA, Ribosomal, 16S; Sucrose; Sugars; Trehalose; Xylitol
PubMed: 32561577
DOI: 10.1128/AEM.01170-20 -
Biomedicines Jun 2020Dental caries is considered to be a preventable disease, and various antimicrobial agents have been developed for the prevention of dental disease. However, many...
BACKGROUND
Dental caries is considered to be a preventable disease, and various antimicrobial agents have been developed for the prevention of dental disease. However, many bacteria show resistance to existing agents.
METHODS/PRINCIPAL FINDINGS
In this study, four known 1,4-naphthoquinones and newly synthesized 10 pyrimidinone-fused 1,4-naphthoquinones, i.e. KHQ 701, 702, 711, 712, 713, 714, 715, 716, 717 and 718, were evaluated for antimicrobial activity against and Pyrimidinone-fused 1,4-naphthoquinones were synthesized in good yields through a series of chemical reactions from a commercially available 1,4-dihydroxynaphthoic acid. MIC values of KHQ 711, 712, 713, 714, 715, 716, 717 and 718 were 6.25-50 μg/mL against (CCARM 5511) 6.25-25 μg/mL against (KACC11954) and (CCARM 3506), 1.56-25 μg/mL against (KACC 13234), 3.125-100 μg/mL against (KACC16833), 1.56-100 μg/mL against (KCTC5809) and (KCTC 5352), 3.125-50 μg/mL against (KCTC 9146) and 3.125-12.5 μg/mL against (KCTC 2640) with a broth microdilution assay. A disk diffusion assay with KHQ derivatives also exhibited strong susceptibility with inhibition zones of 0.96 to 1.2 cm in size against . Among the 10 compounds evaluated, KHQ 711, 712, 713, 715, 716 and 717 demonstrated strong antimicrobial activities against the 9 types of pathogenic oral bacteria. A pyrimidin-4-one moiety comprising a phenyl group at the C2 position and a benzyl group at the N3 position appears to be essential for physiological activity.
CONCLUSION/SIGNIFICANCE
Pyrimidinone-fused 1,4-naphthoquinones synthesized from simple starting compounds and four known 1,4-naphthoquinones were synthesized and showed strong antibacterial activity to the 9 common oral bacteria. These results suggest that these derivatives should be prospective for the treatment of dental diseases caused by oral bacteria, including drug-resistant strains.
PubMed: 32549271
DOI: 10.3390/biomedicines8060160 -
Antimicrobial Agents and Chemotherapy Aug 2020Dental caries is the most common disease in the human mouth. is the primary cariogenic bacterium. Propolis is a nontoxic natural product with a strong inhibitory effect...
Dental caries is the most common disease in the human mouth. is the primary cariogenic bacterium. Propolis is a nontoxic natural product with a strong inhibitory effect on oral cariogenic bacteria. The polyphenol-rich extract from propolis inhibits growth and biofilm formation, as well as the genes involved in virulence and adherence, through the inhibition of glucosyltransferases (GTF). However, because the chemical composition of propolis is highly variable and complex, the mechanism of its antimicrobial action and the active compound are controversial and not completely understood. Caffeic acid phenethyl ester (CAPE) is abundant in the polyphenolic compounds from propolis, and it has many pharmacological effects. In this study, we investigated the antibacterial effects of CAPE on common oral cariogenic bacteria (, , , and ) and its effects on the biofilm-forming and cariogenic abilities of CAPE shows remarkable antimicrobial activity against cariogenic bacteria. Moreover, CAPE also inhibits the formation of biofilms and their metabolic activity in mature biofilms. Furthermore, CAPE can inhibit the key virulence factors of associated with cariogenicity, including acid production, acid tolerance, and the bacterium's ability to produce extracellular polysaccharides (EPS), without affecting bacterial viability at subinhibitory levels. In conclusion, CAPE appears to be a new agent with anticariogenic potential, not only via inhibition of the growth of cariogenic bacteria.
Topics: Anti-Bacterial Agents; Anti-Infective Agents; Biofilms; Caffeic Acids; Dental Caries; Humans; Phenylethyl Alcohol; Streptococcus mutans
PubMed: 32540977
DOI: 10.1128/AAC.00251-20 -
Journal of Endodontics Sep 2020The use of medicaments has been recommended for the treatment of root canal infection. This study evaluated the antimicrobial effect of a well-known biocidal agent,...
INTRODUCTION
The use of medicaments has been recommended for the treatment of root canal infection. This study evaluated the antimicrobial effect of a well-known biocidal agent, sodium dichloroisocyanurate (NaDCC), by comparing it with calcium hydroxide [Ca(OH)] using an engineered 3-species biofilm root canal model.
METHODS
Thirty-eight human single-rooted teeth were decoronated and chemomechanically prepared before inoculation using Enterococcus faecalis, Actinomyces viscosus, and Streptococcus mutans using a flow cell model for 4 weeks for biofilm formation. The samples were randomly divided into 3 groups: NaDCC (n = 12), Ca(OH) (n = 12), and positive control (no medicament, n = 14). The medicaments were placed using a Lentulo spiral. After a contact time of 7 days, the roots were crushed and plated on selective media. Bacterial identities were confirmed with the use of selective media. Colony-forming units were calculated (CFU/ml). Descriptive statistics (mean and standard deviations) were calculated.
RESULTS
Seven-day dressing with NaDCC or Ca(OH) presented with no growth. For the positive control, the mean colony-forming units were 2.97E4 ± 3.42E4 (CFU/ml). All previously inoculated strains were recovered in the control group.
CONCLUSIONS
NaDCC and Ca(OH) when used as intracanal medicaments were able to eradicate an engineered 3-species biofilm in single-rooted teeth in an ex vivo model. NaDCC deserves further investigation as an intracanal medicament.
Topics: Calcium Hydroxide; Dental Pulp Cavity; Enterococcus faecalis; Humans; Root Canal Irrigants; Triazines
PubMed: 32512067
DOI: 10.1016/j.joen.2020.05.011 -
Annales de Dermatologie Et de... Oct 2020Pseudochromhidrosis denotes the production of colourless sweat that acquires colour after coming into contact with exogenous factors such as dyes in clothing, chemicals...
INTRODUCTION
Pseudochromhidrosis denotes the production of colourless sweat that acquires colour after coming into contact with exogenous factors such as dyes in clothing, chemicals or chromogenic microorganisms.
PATIENTS AND METHODS
A 9-year-old girl presented with progressive brown pigmentation predominantly on the nose, forehead, perioral region and cheeks. It was easily removable by rubbing with a moist compress, leaving normal-coloured skin as well as brown pigment on the compress. The same pigmentation recurred within 2h. The patient was not using cosmetics. Bacteriological culture of samples taken by rubbing the skin in affected areas on the face was positive for commensal bacteria of the skin (Actinomyces viscosus, Staphylococcus epidermidis, Cutibacterium acnes and Streptococcus sanguinis). Antibiotic therapy achieved total resolution of symptoms.
CONCLUSION
Bacteria constitute the most frequent aetiology of pseudochromhidrosis. Where such a cutaneous condition exists, even in the absence of positive bacteriological testing, antibiotic therapy would seem to be indicated as a therapeutic test. Biopsy does not appear to be essential as a first-line approach where a bacterial cause is suspected, but it may be proposed in the event of resistance to antibiotics.
Topics: Bacterial Infections; Child; Female; Humans; Pigmentation Disorders; Propionibacterium acnes; Sweat Gland Diseases; Sweating
PubMed: 32498965
DOI: 10.1016/j.annder.2020.04.011