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ACS Applied Bio Materials May 2024Bacterial biofilms play a central role in the development and progression of periodontitis, a chronic inflammatory condition that affects the oral cavity. One solution...
Bacterial biofilms play a central role in the development and progression of periodontitis, a chronic inflammatory condition that affects the oral cavity. One solution to current treatment constraints is using nitric oxide (NO)─with inherent antimicrobial properties. In this study, an antimicrobial coating is developed from the NO donor -nitroso--acetylpenicillamine (SNAP) embedded within polyethylene glycol (PEG) to prevent periodontitis. The SNAP-PEG coating design enabled a controlled NO release, achieving tunable NO levels for more than 24 h. Testing the SNAP-PEG composite on dental floss showed its effectiveness as a uniform and bioactive coating. The coating exhibited antibacterial properties against and , with inhibition zones measuring up to 7.50 ± 0.28 and 14.80 ± 0.46 mm, respectively. Furthermore, SNAP-PEG coating materials were found to be stable when stored at room temperature, with 93.65% of SNAP remaining after 28 d. The coatings were biocompatible against HGF and hFOB 1.19 cells through a 24 h controlled release study. This study presents a facile method to utilize controlled NO release with dental antimicrobial coatings comprising SNAP-PEG. This coating can be easily applied to various substrates, providing a user-friendly approach for targeted self-care in managing gingival infections associated with periodontitis.
Topics: Streptococcus mutans; Nitric Oxide; Escherichia coli; Humans; Anti-Bacterial Agents; Materials Testing; Coated Materials, Biocompatible; Polyethylene Glycols; Microbial Sensitivity Tests; Particle Size; Biofilms; S-Nitroso-N-Acetylpenicillamine; Surface Properties; Periodontitis; Gingiva
PubMed: 38593411
DOI: 10.1021/acsabm.4c00051 -
Microbiology Spectrum May 2024The tenacious biofilms formed by are resistant to conventional antibiotics and current treatments. There is a growing need for novel therapeutics that selectively...
The tenacious biofilms formed by are resistant to conventional antibiotics and current treatments. There is a growing need for novel therapeutics that selectively inhibit biofilms while preserving the normal oral microenvironment. Previous studies have shown that increased levels of cyclic di-AMP, an important secondary messenger synthesized by diadenylate cyclase (DAC), favored biofilm formation in . Thus, targeting DAC is a novel strategy to inhibit biofilms. We screened a small NCI library of natural products using a fluorescence detection assay. (+)-Brazilin, a tetracyclic homoisoflavanoid found in the heartwood of , was identified as one of the 11 "hits," with the greatest reduction (>99%) in fluorescence at 100 µM. The DAC inhibitory profiles of the 11 "hits" established by a quantitative high-performance liquid chromatography assay revealed that (+)-brazilin had the most enzymatic inhibitory activity (87% at 100 µM) and was further studied to determine its half maximal inhibitory concentration (IC = 25.1 ± 0.98 µM). (+)-Brazilin non-competitively inhibits DAC's enzymatic activity ( = 140.0 ± 27.13 µM), as determined by a steady-state Michaelis-Menten kinetics assay. In addition, (+)-brazilin's binding profile with DAC ( = 11.87 µM) was illustrated by a tyrosine intrinsic fluorescence quenching assay. Furthermore, at low micromolar concentrations, (+)-brazilin selectively inhibited the biofilm of (IC = 21.0 ± 0.60 µM) and other oral bacteria. biofilms were inhibited by a factor of 10 in colony-forming units when treated with 50 µM (+)-brazilin. In addition, a significant dose-dependent reduction in extracellular DNA and glucan levels was evident by fluorescence microscopy imaging of biofilms exposed to different concentrations of (+)-brazilin. Furthermore, colonization of on a representative model of enamel using suspended hydroxyapatite discs showed a >90% reduction with 50 µM (+)-brazilin. In summary, we have identified a drug-like natural product inhibitor of biofilm that not only binds to DAC but can also inhibit the function of DAC. (+)-Brazilin could be a good candidate for further development as a potent therapeutic for the prevention and treatment of dental caries.IMPORTANCEThis study represents a significant advancement in our understanding of potential therapeutic options for combating cariogenic biofilms produced by . The research delves into the use of (+)-brazilin, a natural product, as a potent inhibitor of ' diadenylate cyclase (DAC), an enzyme crucial in the formation of biofilms. The study establishes (+)-brazilin as a non-competitive inhibitor of DAC while providing initial insights into its binding mechanism. What makes this finding even more promising is that (+)-brazilin does not limit its inhibitory effects to alone. Instead, it demonstrates efficacy in hindering biofilms in other oral bacteria as well. The broader spectrum of anti-biofilm activity suggests that (+)-brazilin could potentially serve as a versatile tool in a natural product-based treatment for combating a range of conditions caused by resilient biofilms.
Topics: Biofilms; Streptococcus mutans; Isoflavones; Anti-Bacterial Agents; Biological Products; Microbial Sensitivity Tests; Phosphorus-Oxygen Lyases; Bacterial Proteins; Humans
PubMed: 38591917
DOI: 10.1128/spectrum.02418-23 -
JPMA. the Journal of the Pakistan... Mar 2024
Topics: Humans; Chlorhexidine; Streptococcus mutans; Oral Health; Dental Plaque; Saliva; Probiotics; Dental Caries; Colony Count, Microbial
PubMed: 38591271
DOI: 10.47391/JPMA.24-15 -
BMC Neurology Apr 2024Streptococcus intermedius is a member of the S. anginosus group and is part of the normal oral microbiota. It can cause pyogenic infections in various organs, primarily...
BACKGROUND
Streptococcus intermedius is a member of the S. anginosus group and is part of the normal oral microbiota. It can cause pyogenic infections in various organs, primarily in the head and neck area, including brain abscesses and meningitis. However, ventriculitis due to periodontitis has not been reported previously.
CASE PRESENTATION
A 64-year-old male was admitted to the hospital with a headache, fever and later imbalance, blurred vision, and general slowness. Neurological examination revealed nuchal rigidity and general clumsiness. Meningitis was suspected, and the patient was treated with dexamethasone, ceftriaxone and acyclovir. A brain computer tomography (CT) scan was normal, and cerebrospinal fluid (CSF) Gram staining and bacterial cultures remained negative, so the antibacterial treatment was discontinued. Nine days after admission, the patient's condition deteriorated. The antibacterial treatment was restarted, and a brain magnetic resonance imaging revealed ventriculitis. A subsequent CT scan showed hydrocephalus, so a ventriculostomy was performed. In CSF Gram staining, chains of gram-positive cocci were observed. Bacterial cultures remained negative, but a bacterial PCR detected Streptococcus intermedius. An orthopantomography revealed advanced periodontal destruction in several teeth and periapical abscesses, which were subsequently operated on. The patient was discharged in good condition after one month.
CONCLUSIONS
Poor dental health can lead to life-threatening infections in the central nervous system, even in a completely healthy individual. Primary bacterial ventriculitis is a diagnostic challenge, which may result in delayed treatment and increased mortality.
Topics: Male; Humans; Middle Aged; Streptococcus intermedius; Cerebral Ventriculitis; Anti-Bacterial Agents; Meningitis; Central Nervous System Bacterial Infections; Periodontitis
PubMed: 38580923
DOI: 10.1186/s12883-024-03604-4 -
Journal of Global Antimicrobial... Jun 2024Eravacycline, a new tetracycline derivative, exhibits broad-spectrum antimicrobial susceptibility. This study aimed to comprehensively investigate in vitro activities of... (Comparative Study)
Comparative Study
OBJECTIVES
Eravacycline, a new tetracycline derivative, exhibits broad-spectrum antimicrobial susceptibility. This study aimed to comprehensively investigate in vitro activities of eravacycline, tigecycline, and ertapenem against various Gram-positive, Gram-negative, and anaerobic bacteria.
METHODS
Minimum inhibitory concentrations (MICs) were determined using the broth microdilution method. The following bacterial species were collected: vancomycin-sensitive (VS) Enterococci species, vancomycin-resistant Enterococci species (VRE), Staphylococcus aureus, Streptococcus anginosus, Bacteroides species, Clostridioides difficile, Clostridium innocuum, Clostridium perfringens, Parabacteroides distasonis, and Stenotrophomonas maltophilia.
RESULTS
We found that eravacycline exhibited superior in vitro activity compared to tigecycline and ertapenem. Notably, it exhibited the lowest MIC for several bacterial species, including VS E. faecalis (0.12 µg/mL), VS E. faecium (0.12 µg/mL), and others. Besides, VRE was susceptible to eravacycline (MIC:0.12 µg/mL) and tigecycline (MIC:0.12 µg/mL), but was all resistant to ertapenem (MIC > 64 µg/mL). S. aureus was also susceptible to eravacycline (MIC:0.5 µg/mL) as well as tigecycline (MIC:1.0 µg/mL). Furthermore, S. anginosus showed higher susceptibility to eravacycline (MIC:2.0 µg/mL) and tigecycline (MIC:4.0 µg/mL), but lower to ertapenem (MIC:32.0 µg/mL). Eravacycline and tigecycline also demonstrated good susceptibility to anaerobes, including Bacteroides species (susceptibility rate: 100%), P. distasonis (100%), C. difficile (94.1‒100%), C. innocuum (94.1‒96.1%), and C. perfringens (88.9‒96.3%). For S. maltophilia, both tigecycline and eravacycline showed an MIC of 2 µg/mL. A moderate-to-strong correlation (rho = 0.608-0.804, P < 0.001) was noted between the MIC values of eravacycline and tigecycline against various bacterial species.
CONCLUSIONS
Our study highlights the potential of eravacycline as an effective treatment option for multidrug-resistant bacterial infections.
Topics: Microbial Sensitivity Tests; Tigecycline; Tetracyclines; Humans; Anti-Bacterial Agents; Bacteria, Anaerobic; Taiwan; Ertapenem; Staphylococcus aureus; Bacteria, Aerobic; Vancomycin-Resistant Enterococci; Streptococcus anginosus; Clostridioides difficile; Stenotrophomonas maltophilia; Vancomycin; Gram-Negative Bacteria; Gram-Positive Bacteria
PubMed: 38552878
DOI: 10.1016/j.jgar.2024.03.014 -
BMC Complementary Medicine and Therapies Mar 2024Natural products are one of the best candidates for controlling drug-resistant pathogens, the advantages of which include low production costs and low side effects. In...
BACKGROUND
Natural products are one of the best candidates for controlling drug-resistant pathogens, the advantages of which include low production costs and low side effects. In this study, as potential antimicrobials, the anti-bacterial and antibiofilm activities of several Iranian native medicinal plants were screened.
METHODS
The antibacterial/antifungal and anti-biofilm activities of 18 medicinal plants including Reseda lutea L., Nepeta sintenisii Bunge., Stachys turcomanica Trautv., Stachys lavandulifolia Vahl, Diarthron antoninae (Pobed.) Kit Tan., Ziziphora clinopodioides Lam., Euphorbia kopetdaghi Prokh, Euphorbia serpens Kunth., Hymenocrater calycinus Benth., Scutellaria pinnatifida A.Ham., Viola tricolor L., Hypericum helianthemoides (Spach) Boiss., Hypericum scabrum L., Convolvulus lineatus L., Scabiosa rotata M.Bieb Greuter & Burdet, Delphinium semibarbatum Bien. Ex Boiss., Glycyrrhiza triphylla Fisch. & C.A.Mey., and Ziziphus jujuba Mill., against two Gram-positive bacteria, Staphylococcus aureus, Bacillus cereus, as well as two Gram-negative bacteria, Pseudomonas aeruginosa, Escherichia coli; and Candida albicans as a fungal strain, were evaluated. The minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC) values of the extracts against tested microorganisms were reported and we investigated their effect on the biofilm inhibition of Pseudomonas aeruginosa PAO1, Staphylococcus epidermis, Staphylococcus aureus and Streptococcus mutans. In addition, the effect of the extracts on the eradication of the biofilms of these bacteria was evaluated.
RESULTS
In this study, H. scabrum was found to exhibit potentially significant activity against Gram-positive bacteria with the MIC range of 6.25-25 µg/mL. This extract also showed a significant effect on inhibiting the biofilm of S. aureus, S. mutans, and S. epidermidis and eradicating the biofilm of S. epidermidis DSMZ 3270. In addition, Hymenocrater calycinus root extract had moderate antibacterial activity against B. cereus with the MIC and MBC 62.5 µg/mL, respectively.
CONCLUSIONS
The results of this study showed that the root extracts of two plants, Hypericum scabrum and Hymenocrater calycinus, had antimicrobial and anti-biofilm effects. Based on the observed anti-biofilm effects, these two plants may be considered in future studies to find responsible antimicrobial compounds.
Topics: Plants, Medicinal; Iran; Staphylococcus aureus; Plant Extracts; Anti-Infective Agents; Anti-Bacterial Agents; Biofilms; Candida albicans; Pseudomonas aeruginosa; Streptococcus mutans
PubMed: 38549139
DOI: 10.1186/s12906-024-04437-x -
The Journal of Clinical Pediatric... Mar 2024Fluoridated dentifrices have antibacterial effects on children's teeth. On the other hand, the side effects encountered with the use of them have led researchers to look...
Fluoridated dentifrices have antibacterial effects on children's teeth. On the other hand, the side effects encountered with the use of them have led researchers to look for safe alternatives. This study aimed to determine the antibacterial effect of different commercially available fluoride-free dentifrices on () in comparison with different concentrations of fluoridated dentifrices. Study groups comprised of fluoride-free dentifrices, which contain Probiotic (Activated Charcoal Probiotic Dentifrice-Group P), Aloe Vera-Group AV and Salivary Proteins-Group SP. Fluoridated dentifrices containing 1450 ppm fluoride-Control Group 1 and 500 ppm fluoride-Control Group 2 served as control groups. Antibacterial activity was assessed by Minimum Inhibitory Concentrations and agar well diffusion assays on . Biofilm inhibition assay was performed with dentifrices, which had antibacterial activities, and a negative control phosphate-buffered saline (Group PBS) on sterile hydroxyapatite discs against . Statistical evaluation was performed. Only group AV showed an antibacterial effect on , while control groups showed a similar antibacterial effect. The mean number of viable bacteria present in biofilm in Control Group 1 and 2 and Group AV were statistically significantly lower than that in Group PBS, but there were no statistically significant differences between Control Groups and Group AV. Antibacterial activity of commercial dentifrices against may be exerted by antibacterial components other than fluoride. Aloe vera-containing toothpaste showed an antibacterial effect on , although not as much as the fluoride-containing toothpastes in the control groups. However, further and long-term studies are required.
Topics: Child; Humans; Dentifrices; Fluorides; Streptococcus mutans; Toothpastes; Anti-Bacterial Agents
PubMed: 38548635
DOI: 10.22514/jocpd.2024.035 -
The Journal of Clinical Pediatric... Mar 2024In this case-control study, we aimed to investigate the specific oral pathogens potentially associated with the mobile microbiome in children with congenital heart...
In this case-control study, we aimed to investigate the specific oral pathogens potentially associated with the mobile microbiome in children with congenital heart disease (CHD). Caries, oral hygiene and gingival indices were evaluated in 20 children with CHD and a healthy control group, and venous blood samples and saliva were collected. Using quantitative polymerase chain reaction (qPCR), blood samples were analyzed for the presence of bacterial DNA to determine the mobile microbiome, and saliva samples were analyzed to identify and quantify target microorganisms, including () and its serotype (), (), (), () and () and its JP2 clone (). The findings were analyzed by Mann Whitney U, chi-square, Fisher's exact and Spearman's Correlation tests. Bacterial DNA was identified in two blood samples. No significant differences were found between the groups regarding the presence and counts of bacteria in saliva. However, the CHD group exhibited significantly lower caries and higher gingival index scores than the control group. The presence of and were significantly associated with higher gingival index scores. and counts were significantly correlated with caries experience. A positive correlation was found between and total bacteria counts. In conclusion, the mobile microbiome, which has been proposed as a potential marker of dysbiosis at distant sites, was very rare in our pediatric population. The counts of target microorganisms which are potentially associated with the mobile microbiome did not differ in children with CHD and healthy children.
Topics: Humans; Child; DNA, Bacterial; Case-Control Studies; Saliva; Heart Defects, Congenital; Porphyromonas gingivalis; Dental Caries; Streptococcus mutans; Fusobacterium nucleatum; Microbiota
PubMed: 38548632
DOI: 10.22514/jocpd.2024.026 -
Rhode Island Medical Journal (2013) Apr 2024Brain abscess is a rare complication of esophagogastro- duodenoscopy (EGD) with few reported cases in the literature. In this report, we discuss a patient presenting...
Brain abscess is a rare complication of esophagogastro- duodenoscopy (EGD) with few reported cases in the literature. In this report, we discuss a patient presenting with altered mental status, headache, and dysarthria due to brain abscess caused by S. intermedius shortly after an EGD with an esophageal biopsy showing a new diagnosis of eosinophilic esophagitis. We highlight the rare association of EGD and brain abscess, and discuss the importance of prompt diagnosis and treatment.
Topics: Humans; Eosinophilic Esophagitis; Streptococcus intermedius; Duodenoscopy; Biopsy; Brain Abscess
PubMed: 38536131
DOI: No ID Found -
Molecular Biology and Evolution Mar 2024Ancient microbial genomes can illuminate pathobiont evolution across millenia, with teeth providing a rich substrate. However, the characterization of prehistoric oral...
Ancient microbial genomes can illuminate pathobiont evolution across millenia, with teeth providing a rich substrate. However, the characterization of prehistoric oral pathobiont diversity is limited. In Europe, only preagricultural genomes have been subject to phylogenetic analysis, with none compared to more recent archaeological periods. Here, we report well-preserved microbiomes from two 4,000-year-old teeth from an Irish limestone cave. These contained bacteria implicated in periodontitis, as well as Streptococcus mutans, the major cause of caries and rare in the ancient genomic record. Despite deriving from the same individual, these teeth produced divergent Tannerella forsythia genomes, indicating higher levels of strain diversity in prehistoric populations. We find evidence of microbiome dysbiosis, with a disproportionate quantity of S. mutans sequences relative to other oral streptococci. This high abundance allowed for metagenomic assembly, resulting in its first reported ancient genome. Phylogenetic analysis indicates major postmedieval population expansions for both species, highlighting the inordinate impact of recent dietary changes. In T. forsythia, this expansion is associated with the replacement of older lineages, possibly reflecting a genome-wide selective sweep. Accordingly, we see dramatic changes in T. forsythia's virulence repertoire across this period. S. mutans shows a contrasting pattern, with deeply divergent lineages persisting in modern populations. This may be due to its highly recombining nature, allowing for maintenance of diversity through selective episodes. Nonetheless, an explosion in recent coalescences and significantly shorter branch lengths separating bacteriocin-carrying strains indicate major changes in S. mutans demography and function coinciding with sugar popularization during the industrial period.
Topics: Humans; Phylogeny; Streptococcus mutans; Genomics; Metagenome; Microbiota
PubMed: 38533900
DOI: 10.1093/molbev/msae017