Thermal Treatments Modulate Bacterial Adhesion to Dental Enamel

2011 ◽  
Vol 90 (12) ◽  
pp. 1451-1456 ◽  
Author(s):  
X.L. Hu ◽  
B. Ho ◽  
C.T. Lim ◽  
C.S. Hsu
Keyword(s):  
Thermal Treatment ◽  
Zeta Potential ◽  
Physicochemical Properties ◽  
Bacterial Adhesion ◽  
Laser Scanning ◽  
Adhesion Force ◽  
Bacterial Species ◽  
Dental Enamel ◽  
Laser Scanning Microscopy ◽  
Confocal Laser

Numerous studies have demonstrated the effects of laser-induced heat on demineralization of enamel; however, no studies have investigated the link between heat/laser-induced changes in physicochemical properties and bacterial adhesion. In this study, we investigated the effects of thermal treatment on surface properties of enamel such as hydrophobicity and zeta potential. Bacterial adhesion to treated surfaces was characterized by confocal laser scanning microscopy, and adhesion force was quantified by atomic force microscopy. The hydrophobicity of enamel increased after heating (p < 0.05), and the zeta potential of heated enamel became more negative than that of the control (p < 0.01). Streptococcus oralis and S. mitis were more hydrophilic than S. sanguis, with more negative zeta potential (all p < 0.01). S. mitis and S. oralis occupied significantly less area on enamel after being heated (p < 0.05). Heating reduced the adhesion force of both S. mitis and S. oralis to enamel with or without saliva coating. Reduction of adhesion force was statistically significant for S. mitis (p < 0.01), whereas that of S. oralis was not statistically significant (p > 0.05). Heating did not affect the adhesion of S. sanguis with or without saliva coating. In conclusion, thermal treatment and photothermal/laser treatments may modulate the physicochemical properties of enamel, preventing the adhesion of some bacterial species.

scholarly journals Polymeric Nanoparticles Active against Dual-Species Bacterial Biofilms

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4958
Author(s):  
Jessa Marie V. Makabenta ◽  
Jungmi Park ◽  
Cheng-Hsuan Li ◽  
Aritra Nath Chattopadhyay ◽  
Ahmed Nabawy ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Laser Scanning ◽  
Polymeric Nanoparticles ◽  
Bacterial Species ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Bacterial Biofilms ◽  
Global Public Health ◽  
Bacterial Strains

Biofilm infections are a global public health threat, necessitating new treatment strategies. Biofilm formation also contributes to the development and spread of multidrug-resistant (MDR) bacterial strains. Biofilm-associated chronic infections typically involve colonization by more than one bacterial species. The co-existence of multiple species of bacteria in biofilms exacerbates therapeutic challenges and can render traditional antibiotics ineffective. Polymeric nanoparticles offer alternative antimicrobial approaches to antibiotics, owing to their tunable physico-chemical properties. Here, we report the efficacy of poly(oxanorborneneimide) (PONI)-based antimicrobial polymeric nanoparticles (PNPs) against multi-species bacterial biofilms. PNPs showed good dual-species biofilm penetration profiles as confirmed by confocal laser scanning microscopy. Broad-spectrum antimicrobial activity was observed, with reduction in both bacterial viability and overall biofilm mass. Further, PNPs displayed minimal fibroblast toxicity and high antimicrobial activity in an in vitro co-culture model comprising fibroblast cells and dual-species biofilms of Escherichia coli and Pseudomonas aeruginosa. This study highlights a potential clinical application of the presented polymeric platform.

scholarly journals Comparison of Antibacterial Adhesion When Salivary Pellicle Is Coated on Both Poly(2-hydroxyethyl-methacrylate)- and Polyethylene-glycol-methacrylate-grafted Poly(methyl methacrylate)

2018 ◽  
Vol 19 (9) ◽  
pp. 2764 ◽  
Author(s):  
Bor-Shiunn Lee ◽  
Yu-Jia Chen ◽  
Ta-Chin Wei ◽  
Tien-Li Ma ◽  
Che-Chen Chang
Keyword(s):  
Polyethylene Glycol ◽  
Bacterial Adhesion ◽  
Laser Scanning ◽  
Attenuated Total Reflection ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Hydroxyethyl Methacrylate ◽  
Surface Charges ◽  
Glycol Methacrylate ◽  
Salivary Pellicle

Although poly(2-hydroxyethyl methacrylate) (pHEMA) and polyethylene glycol methacrylate (PEGMA) have been demonstrated to inhibit bacterial adhesion, no study has compared antibacterial adhesion when salivary pellicle is coated on polymethyl methacrylate (PMMA) grafted with pHEMA and on PMMA grafted with PEGMA. In this study, PMMA discs were fabricated from a commercial orthodontic acrylic resin system (Ortho-Jet). Attenuated total reflection-Fourier transform infrared spectra taken before and after grafting confirmed that pHEMA and PEGMA were successfully grafted on PMMA. Contact angle measurements revealed PMMA-pHEMA to be the most hydrophilic, followed by PMMA-PEGMA, and then by PMMA. Zeta potential analysis revealed the most negative surface charges on PMMA-PEGMA, followed by PMMA-pHEMA, and then by PMMA. Confocal laser scanning microscopy showed green fluorescence in the background, indicating images that influenced the accuracy of the quantification of live bacteria. Both the optical density value measured at 600 nm and single plate-serial dilution spotting showed that pHEMA was more effective than PEGMA against Escherichia coli and Streptococcus mutans, although the difference was not significant. Therefore, the grafting of pHEMA and PEGMA separately on PMMA is effective against bacterial adhesion, even after the grafted PMMA were coated with salivary pellicle. Surface hydrophilicity, bactericidality, and Coulomb repulsion between the negatively charged bacteria and the grafted surface contributed to the effectiveness.

scholarly journals Bacterial colonization of enamel in situ investigated using fluorescence in situ hybridization

2009 ◽  
Vol 58 (10) ◽  
pp. 1359-1366 ◽  
Author(s):  
Ali Al-Ahmad ◽  
Marie Follo ◽  
Ann-Carina Selzer ◽  
Elmar Hellwig ◽  
Matthias Hannig ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Laser Scanning ◽  
Bacterial Colonization ◽  
Bacterial Species ◽  
Fusobacterium Nucleatum ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Actinomyces Naeslundii ◽  
Oral Biofilms

Oral biofilms are one of the greatest challenges in dental research. The present study aimed to investigate initial bacterial colonization of enamel surfaces in situ using fluorescence in situ hybridization (FISH) over a 12 h period. For this purpose, bovine enamel slabs were fixed on buccal sites of individual splints worn by six subjects for 2, 6 and 12 h to allow biofilm formation. Specimens were processed for FISH and evaluated with confocal laser-scanning microscopy, using probes for eubacteria, Streptococcus species, Veillonella species, Fusobacterium nucleatum and Actinomyces naeslundii. The number of adherent bacteria increased with time and all tested bacterial species were detected in the biofilm formed in situ. The general percentage composition of the eubacteria did not change over the investigated period, but the number of streptococci, the most frequently detected species, increased significantly with time (2 h: 17.7±13.8 %; 6 h: 20.0±16.6 %; 12 h: 24.7±16.1 %). However, ≤1 % of the surface was covered with bacteria after 12 h of biofilm formation in situ. In conclusion, FISH is an appropriate method for quantifying initial biofilm formation in situ, and the proportion of streptococci increases during the first 12 h of bacterial adherence.

scholarly journals Bacteria on Catheters in Patients Undergoing Peritoneal Dialysis

2013 ◽  
Vol 33 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Maria Pihl ◽  
Julia R. Davies ◽  
Ann-Cathrine Johansson ◽  
Gunnel Svensäter
Keyword(s):  
Peritoneal Dialysis ◽  
Laser Scanning ◽  
Close Association ◽  
Bacterial Species ◽  
Clinical Signs ◽  
Single Species ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Rrna Gene ◽  
Micro Organisms

♦BackgroundPeritonitis is the leading cause of morbidity for peritoneal dialysis (PD) patients, and microbial biofilms have previously been identified on catheters from infected patients. However, few studies of catheters from patients without clinical signs of infection have been undertaken. The aim of the present study was to investigate the extent to which bacteria are present on catheters from PD patients with no symptoms of infection.♦MethodsMicrobiologic culturing under aerobic and anaerobic conditions and confocal laser scanning microscopy were used to determine the distribution of bacteria on PD catheters from 15 patients without clinical signs of infection and on catheters from 2 infected patients. The 16S rRNA gene sequencing technique was used to identify cultured bacteria.♦ResultsBacteria were detected on 12 of the 15 catheters from patients without signs of infection and on the 2 catheters from infected patients. Single-species and mixed-microbial communities containing up to 5 species were present on both the inside and the outside along the whole length of the colonized catheters. The bacterial species most commonly found were the skin commensals Staphylococcus epidermidis and Propionibacterium acnes, followed by S. warneri and S. lugdunensis. The strains of these micro-organisms, particularly those of S. epidermidis, varied in phenotype with respect to their tolerance of the major classes of antibiotics.♦ConclusionsBacteria were common on catheters from patients without symptoms of infection. Up to 4 different bacterial species were found in close association and may represent a risk factor for the future development of peritonitis in patients hosting such micro-organisms.

scholarly journals Staphylococcus aureus Interferes with Streptococci Spatial Distribution and with Protein Expression of Species within a Polymicrobial Oral Biofilm

Antibiotics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 116
Author(s):  
Etyene Schnurr ◽  
Pune N. Paqué ◽  
Thomas Attin ◽  
Paolo Nanni ◽  
Jonas Grossmann ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Laser Scanning ◽  
Bacterial Species ◽  
Fusobacterium Nucleatum ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Oral Diseases ◽  
Streptococcus Oralis ◽  
Oral Environment ◽  
Associated Species

We asked whether transient Staphylococcus aureus in the oral environment synergistically interacts with orally associated bacterial species such as Actinomyces oris, Candida albicans, Fusobacterium nucleatum, Streptococcus oralis, Streptococcus mutans, and Veillonella dispar (six-species control biofilm 6S). For this purpose, four modified biofilms with seven species that contain either the wild type strain of the S. aureus genotype (USA300-MRSA WT), its isogenic mutant with MSCRAMM deficiency (USA300-MRSA ΔMSCRAMM), a methicillin-sensitive S. aureus (ST72-MSSA-) or a methicillin-resistant S. aureus (USA800-MRSA) grown on hydroxyapatite disks were examined. Culture analyses, confocal-laser-scanning microscopy and proteome analyses were performed. S. aureus strains affected the amount of supragingival biofilm-associated species differently. The deletion of MSCRAMM genes disrupted the growth of S. aureus and the distribution of S. mutans and S. oralis within the biofilms. In addition, S. aureus caused shifts in the number of detectable proteins of other species in the 6S biofilm. S. aureus (USA300-MRSA WT), aggregated together with early colonizers such as Actinomyces and streptococci, influenced the number of secondary colonizers such as Fusobacterium nucleatum and was involved in structuring the biofilm architecture that triggered the change from a homeostatic biofilm to a dysbiotic biofilm to the development of oral diseases.

scholarly journals Novel Model for Multispecies Biofilms That Uses Rigid Gas-Permeable Lenses

2011 ◽  
Vol 77 (10) ◽  
pp. 3413-3421 ◽  
Author(s):  
Rebecca Peyyala ◽  
Sreenatha S. Kirakodu ◽  
Jeffrey L. Ebersole ◽  
Karen F. Novak
Keyword(s):  
Laser Scanning ◽  
Bacterial Species ◽  
Disease Process ◽  
Laser Scanning Microscopy ◽  
Host Cells ◽  
Confocal Laser ◽  
Content Type ◽  
Oral Biofilms ◽  
Multispecies Biofilms

ABSTRACTOral biofilms comprise complex multispecies consortia aided by specific inter- and intraspecies interactions occurring among commensals and pathogenic bacterial species. Oral biofilms are primary initiating factors of periodontal disease, although complex multifactorial biological influences, including host cell responses, contribute to the individual outcome of the disease. To provide a system to study initial stages of interaction between oral biofilms and the host cells that contribute to the disease process, we developed a novelin vitromodel system to grow biofilms on rigid gas-permeable contact lenses (RGPLs), which enable oxygen to permeate through the lens material. Bacterial species belonging to early- and late-colonizing groups were successfully established as single- or three-species biofilms, with each group comprisingStreptococcus gordonii,Streptococcus oralis, andStreptococcus sanguinis;S. gordonii,Actinomyces naeslundii, andFusobacterium nucleatum; orS. gordonii,F. nucleatum, andPorphyromonas gingivalis. Quantification of biofilm numbers by quantitative PCR (qPCR) revealed substantial differences in the magnitude of bacterial numbers in single-species and multispecies biofilms. We evaluated cell-permeable conventional nucleic acid stains acridine orange, hexidium iodide, and Hoechst 33258 and novel SYTO red, blue, and green fluorochromes for their effect on bacterial viability and fluorescence yield to allow visualization of the aggregates of individual bacterial species by confocal laser scanning microscopy (CLSM). Substantial differences in the quantity and distribution of the species in the multispecies biofilms were identified. The specific features of these biofilms may help us better understand the role of various bacteria in local challenge of oral tissues.

scholarly journals Mapping of a Subgingival Dual-Species Biofilm Model Using Confocal Raman Microscopy

2021 ◽  
Vol 12 ◽  
Author(s):  
Lukas Simon Kriem ◽  
Kevin Wright ◽  
Renzo Alberto Ccahuana-Vasquez ◽  
Steffen Rupp
Keyword(s):  
Laser Scanning ◽  
Bacterial Species ◽  
Raman Microscopy ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Spectroscopic Techniques ◽  
Confocal Raman Microscopy ◽  
Biofilm Model ◽  
Confocal Raman

Techniques for continuously monitoring the formation of subgingival biofilm, in relation to the determination of species and their accumulation over time in gingivitis and periodontitis, are limited. In recent years, advancements in the field of optical spectroscopic techniques have provided an alternative for analyzing three-dimensional microbiological structures, replacing the traditional destructive or biofilm staining techniques. In this work, we have demonstrated that the use of confocal Raman spectroscopy coupled with multivariate analysis provides an approach to spatially differentiate bacteria in an in vitro model simulating a subgingival dual-species biofilm. The present study establishes a workflow to evaluate and differentiate bacterial species in a dual-species in vitro biofilm model, using confocal Raman microscopy (CRM). Biofilm models of Actinomyces denticolens and Streptococcus oralis were cultured using the “Zürich in vitro model” and were analyzed using CRM. Cluster analysis was used to spatially differentiate and map the biofilm model over a specified area. To confirm the clustering of species in the cultured biofilm, confocal laser scanning microscopy (CLSM) was coupled with fluorescent in vitro hybridization (FISH). Additionally, dense bacteria interface area (DBIA) samples, as an imitation of the clusters in a biofilm, were used to test the developed multivariate differentiation model. This confirmed model was successfully used to differentiate species in a dual-species biofilm and is comparable to morphology. The results show that the developed workflow was able to identify main clusters of bacteria based on spectral “fingerprint region” information from CRM. Using this workflow, we have demonstrated that CRM can spatially analyze two-species in vitro biofilms, therefore providing an alternative technique to map oral multi-species biofilm models.

Functionalising antibiotics with nitroxides as an effective broad-spectrum biofilm eradication strategy.

2020 ◽  
Author(s):  
Anthony Verderosa ◽  
Kathryn Fairfull-Smith ◽  
Makrina Totsika
Keyword(s):  
Laser Scanning ◽  
Antimicrobial Agents ◽  
Bacterial Species ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Specific Test ◽  
E Coli ◽  
Cell Counts ◽  
Eradication Strategy ◽  
New Generation

&lt;p&gt;&lt;strong&gt;Background:&lt;/strong&gt;&lt;/p&gt; &lt;p&gt;The adhesion of planktonic bacteria to a surface (biotic or abiotic), and their subsequent ability to aggregate into multicellular communities called biofilms, is a major driving force of failing antibiotic therapy and persistence in chronic infections caused by a variety of pathogens (e.g., &lt;em&gt;Pseudomonas aeruginosa&lt;/em&gt;, &lt;em&gt;Escherichia coli&lt;/em&gt;, and &lt;em&gt;Staphylococcus aureus)&lt;/em&gt;&amp;#160;and plaguing healthcare systems worldwide. Biofilms are estimated to be involved in over 80% of all microbial infections in humans, and commonly exhibit extreme resistance to conventional antimicrobial treatments. Consequently, there is an urgent need for novel antimicrobial agents, which target biofilm residing cells. Here, we present the development and evaluation of a new generation of dual-acting nitroxide functionalised antibiotics with potent biofilm eradication activity.&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Methodology:&lt;/strong&gt;&lt;/p&gt; &lt;p&gt;Synthetic organic chemistry was utilised to produce a new generation of nitroxide functionalised antibiotics with targeted biofilm eradication capabilities. These compounds were tested for biofilm eradication and/or dispersal of several bacterial species using the MBEC&lt;sup&gt;TM&lt;/sup&gt; device, a reproducible high-throughput static biofilm formation system. Mature biofilms were treated with serial dilutions of the specific test agent(s) and recovered bacterial numbers were quantified by absorbance spectroscopy at 600 nm or plating for viable cell counts. Treated biofilms were also stained with Live/Dead (SYTO-9/PI) bacterial viability kit and analysed by fluorescence and confocal laser scanning microscopy.&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;&lt;/p&gt; &lt;p&gt;Nitroxide functionalised antibiotics exhibit potent biofilm-eradication activity against a variety of medically important pathogens, including &lt;em&gt;P. aeruginosa&lt;/em&gt;, uropathogenic &lt;em&gt;E. coli&lt;/em&gt;, and &lt;em&gt;S. aureus&lt;/em&gt;. In Minimal Biofilm Eradication Concentration (MBEC) assays nitroxide functionalised antibiotics were 64-fold more potent against &lt;em&gt;S. aureus&lt;/em&gt; biofilms, and at least 2-fold more potent against uropathogenic &lt;em&gt;E. coli&lt;/em&gt; biofilms than the parent antibiotic ciprofloxacin.&lt;/p&gt; &lt;p&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt;&lt;/p&gt; &lt;p&gt;Currently, antibiotics are often entirely ineffective against biofilm infections. Nitroxide functionalised antibiotics represent a promising new strategy, which could circumvent the resistance of Gram-positive and Gram-negative biofilms to conventional treatments.&lt;/p&gt;

scholarly journals Interactions between L. monocytogenes and P. fluorescens in Dual-Species Biofilms under Simulated Dairy Processing Conditions

Foods ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 176
Author(s):  
Francesca Maggio ◽  
Chiara Rossi ◽  
Clemencia Chaves-López ◽  
Annalisa Serio ◽  
Luca Valbonetti ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Bacterial Species ◽  
Laser Scanning Microscopy ◽  
Blue Pigment ◽  
Confocal Laser ◽  
Processing Conditions ◽  
Experimental Conditions ◽  
Dairy Processing ◽  
Microscopy Analysis ◽  
Sessile Cells

In dairy processing environments, many bacterial species adhere and form biofilms on surfaces and equipment, leading to foodborne illness and food spoilage. Among them, Listeria monocytogenes and Pseudomonas spp. could be present in mixed-species biofilms. This study aimed to evaluate the interactions between L. monocytogenes and P. fluorescens in biofilms simulating dairy processing conditions, as well as the capability of P. fluorescens in co-culture to produce the blue pigment in a Ricotta-based model system. The biofilm-forming capability of single- and mixed-cultures was evaluated on polystyrene (PS) and stainless steel (SS) surfaces at 12 °C for 168 h. The biofilm biomass was measured, the planktonic and sessile cells and the carbohydrates in biofilms were quantified. The biofilms were also observed through Confocal Laser Scanning Microscopy analysis. Results showed that only P. fluorescens was able to form biofilms on PS. Moreover, in dual-species biofilms at the end of the incubation time (168 h at 12 °C), a lower biomass compared to P. fluorescens mono-species was observed on PS. On SS, the biofilm cell population of L. monocytogenes was higher in the dual-species than in mono-species, particularly after 48 h. Carbohydrates quantity in the dual-species system was higher than in mono-species and was revealed also at 168 h. The production of blue pigment by P. fluorescens was revealed both in single- and co-culture after 72 h of incubation (12 °C). This work highlights the interactions between the two species, under the experimental conditions studied in the present research, which can influence biofilm formation (biomass and sessile cells) but not the capability of P. fluorescens to produce blue pigment.

Exploration of Nanoethosomal Transgel of Naproxen Sodium for the Treatment of Arthritis

2020 ◽  
Vol 17 (10) ◽  
pp. 885-897
Author(s):  
Farzana Anjum ◽  
Foziyah Zakir ◽  
Devina Verma ◽  
Mohd Aqil ◽  
Manvi Singh ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Drug Release ◽  
Zeta Potential ◽  
Laser Scanning ◽  
Naproxen Sodium ◽  
Entrapment Efficiency ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Paw Edema ◽  
Rat Paw Edema

Background: The present work aimed to develop an ethosomal gel of naproxen sodium for the amelioration of rheumatoid arthritis. Objective: In the present work, we have explored the potential of ethosomes to deliver naproxen into deeper skin strata. Further, the anti-inflammatory efficacy of naproxen ethosomal formulation was assessed using the carrageenan-induced rat paw edema model. Methods: Naproxen sodium nanoethosomes were prepared using different proportions of lipoid S100 (50mg-200mg), ethanol (20-50%) and water, and were further characterized on the basis of vesicle morphology, entrapment efficiency, zeta potential, in-vitro drug release and ex-vivo permeation studies. Results: The optimized ethosomal formulation was found to have 129 ± 0.01 nm particle size, 0.295 Polydispersity Index (PDI), -3.29 mV zeta potential, 88% entrapment efficiency and 96.573% drug release in 24 hours. TEM and SEM analysis of the optimized formulation showed slightly smooth spherical structures. The Confocal laser scanning microscopy showed that ethosomes could easily infiltrate into deeper dermal layers (upto 104.9μm) whereas the hydroalcoholic solution of the drug could penetrate up to 74.9μm. Further, the optimized ethosomal formulation was incorporated into 1% carbopol 934 gel base and optimized wherein the transdermal flux was found to be approximately 10 times more than the hydroethanolic solution. Also, the in-vivo pharmacodynamic study of the optimized ethosomal gel exhibited a higher percentage inhibition of swelling paw edema than marketed diclofenac gel. Conclusion: The ethosomal gel was successfully developed and has shown the potential to be a good option for the replacement of conventional therapies of rheumatoid arthritis.

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