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Manphibool C, Matangkasombut O, Chantarangsu S, Chantarawaratit PO. Effects of blue-light LED toothbrush on reducing dental plaque and gingival inflammation in orthodontic patients with fixed appliances: a crossover randomized controlled trial. BMC Oral Health 2023; 23:293. [PMID: 37189136 DOI: 10.1186/s12903-023-02977-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 04/18/2023] [Indexed: 05/17/2023] Open
Abstract
BACKGROUND Patients with fixed orthodontic appliances have higher plaque accumulation and gingival inflammation. Our aim was to compare the effectiveness of a light emitting diode (LED) toothbrush with a manual toothbrush in reducing dental plaque and gingival inflammation in orthodontic patients with fixed appliances, and to investigate the effect of the LED toothbrush on Streptococcus mutans (S. mutans) biofilm in vitro. METHODS Twenty-four orthodontic patients were recruited and randomly assigned into 2 groups: (1) started with manual and (2) started with LED toothbrushes. After a 28-day usage and 28-day wash-out period, the patients switched to the other intervention. The plaque and gingival indices were determined at baseline and 28 days after each intervention. The patients' compliance and satisfaction scores were collected using questionnaires. For the in vitro experiments, S. mutans biofilm was divided into 5 groups (n = 6) with 15-, 30-, 60-, or 120-sec LED exposure, and without LED exposure as a control group. RESULTS There was no significant difference in the gingival index between the manual and LED toothbrush groups. The manual toothbrush was significantly more effective in reducing the plaque index in the proximal area on the bracket side (P = 0.031). However, no significant difference was found between the two groups in other areas around the brackets or on the non-bracket side. After LED exposure in vitro, the percentages of bacterial viability after LED exposure for 15-120 s were significantly lower compared with the control (P = 0.006). CONCLUSION Clinically, the LED toothbrush was not more effective in reducing dental plaque or gingival inflammation than the manual toothbrush in orthodontic patients with fixed appliances. However, the blue light from the LED toothbrush significantly reduced the number of S. mutans in biofilm when it was exposed to the light for at least 15 s in vitro. CLINICAL TRIAL REGISTRATION Thai Clinical Trials Registry (TCTR20210510004). Registered 10/05/2021.
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Affiliation(s)
- Chavirakarn Manphibool
- Department of Orthodontics, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Oranart Matangkasombut
- Department of Microbiology and Center of Excellence on Oral Microbiology and Immunology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
| | - Soranun Chantarangsu
- Department of Oral Pathology, Faculty of Dentistry, Chulalongkorn University, Bangkok, Thailand
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Blue Light Sensing BlsA-Mediated Modulation of Meropenem Resistance and Biofilm Formation in Acinetobacter baumannii. mSystems 2023; 8:e0089722. [PMID: 36622157 PMCID: PMC9948694 DOI: 10.1128/msystems.00897-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The presence or absence of BlsA, a protein with a blue light-sensing flavin domain in the genomes of Acinetobacter species has aroused curiosity about its roles in the regulation of bacterial lifestyle under light. Genomic and transcriptomic analyses revealed the loss of BlsA in several multidrug-resistant (MDR) A. baumannii strains as well as the light-mediated induction of blsA, along with a possible BlsA-interacting partner BipA. Their direct in vivo interactions were verified using a bacterial two-hybrid system. The results demonstrated that the C-terminal region of BipA could bind to the C-terminal residues of BlsA under blue light at 23°C but not at 37°C. Genetic manipulations of blsA and bipA revealed that the coexistence of BlsA and BipA was required to induce the light-dependent expression of ompA in A. baumannii ATCC 17978 at 23°C. The same phenomenon occurred in the BlsA-deficient MDR strain in our functional complementation assay; however, the underlying molecular mechanism remains poorly understood. BlsA-modulated amounts of OmpA, the most abundant porin, in the outer membrane affected the membrane integrity and permeability of small molecules. Dark conditions or the deletion of ompA made the membrane more permeable to lipophilic ethidium bromide (EtBr) but not to meropenem. Interestingly, light illumination and low temperature conditions made the cells more sensitive to meropenem; however, this bactericidal effect was not noted in the blsA mutant or in the BlsA-deficient MDR strains. Light-mediated cell death and the reduction of biofilm formation at 23°C were abolished in the blsA mutant strain, suggesting multifaceted roles of BlsA in A. baumannii strains. IMPORTANCE Little is known about the functional roles of BlsA and its interacting partners in Acinetobacter species. Intriguingly, no BlsA homolog was found in several clinical isolates, suggesting that BlsA was not required inside the host because of the lack of blue light and the warm temperature conditions. As many chromophore-harboring proteins interact with various partners to control light-dependent cellular behaviors, the maintenance of blsA in the genomes of many Acinetobacter species during their evolution may be beneficial when fluctuations occur in two important environmental factors: light and temperature. Our study is the first to report the novel protein partner of BlsA, namely, BipA, and its contribution to multiple phenotypic changes, including meropenem resistance and biofilm formation. Rapid physiological acclimation to changing light or temperature conditions may be possible in the presence of the light-sensing BlsA protein, which may have more interacting partners than expected.
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Prado TP, Zanchetta FC, Barbieri B, Aparecido C, Melo Lima MH, Araujo EP. Photobiomodulation with Blue Light on Wound Healing: A Scoping Review. Life (Basel) 2023; 13:575. [PMID: 36836932 PMCID: PMC9959862 DOI: 10.3390/life13020575] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/22/2023] Open
Abstract
BACKGROUND Photobiomodulation consists of inducing healing by irradiating light. This scoping review investigates the effect of blue light on the healing process. METHODS The MEDLINE, Web of Science, Scopus, and CINAHL databases were searched. Two reviewers independently examined the search results and extracted data from the included studies. A descriptive analysis was performed. RESULTS Twenty-two articles were included. Studies were categorized as in vitro/mixed, preclinical, and clinical. The power density used was 10-680 mW/cm2 in most of the in vitro/preclinical studies, the irradiation time ranged from 5 s to 10 min, and different wavelengths and energy densities were used. In clinical studies, the wavelength ranged from 405 to 470 nm, and the energy density varied from 1.5 to 30 J/cm2. CONCLUSIONS A low energy density (<20 J/cm2) was able to stimulate the different cell types and proteins involved in healing, while a high energy density, 20.6-50 J/cm2, significantly reduced cell proliferation, migration, and metabolism. There is a great variety of device parameters among studies, and this makes it difficult to conclude what the best technical specifications are. Thus, further studies should be performed in order to define the appropriate parameters of light to be used.
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Affiliation(s)
- Thais P. Prado
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | - Flávia Cristina Zanchetta
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | - Beatriz Barbieri
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | - Caroline Aparecido
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | - Maria Helena Melo Lima
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
| | - Eliana P. Araujo
- School of Nursing, University of Campinas (Unicamp), Campinas 13083-887, Brazil
- Laboratory of Cell Signaling, Obesity and Comorbidities Research Center, University of Campinas, Campinas 13083-864, Brazil
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Xue VW, Yin IX, Niu JY, Lo ECM, Chu CH, Zhao IS. Effects of a 445 nm diode laser and silver diamine fluoride in preventing enamel demineralisation and inhibiting cariogenic bacteria. J Dent 2022; 126:104309. [PMID: 36162639 DOI: 10.1016/j.jdent.2022.104309] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Revised: 09/20/2022] [Accepted: 09/22/2022] [Indexed: 10/31/2022] Open
Abstract
OBJECTIVE To study the effects of a 445 nm diode laser (L) and silver diamine fluoride (F) on preventing enamel demineralisation and inhibiting cariogenic bacteria. METHODS Thirty-three enamel slices were sectioned each into four blocks for four groups to receive L with F (LF), F, L and Water (W, control). Ten blocks from each group were used to evaluate demineralization. Surface morphology, lesion depth and nanohardness of the blocks after pH-cycling were studied by scanning electron microscopy (SEM), nanohardness test, and micro-computed tomography, respectively. Twenty-three blocks per group were used for biofilm assessment. Morphology, viability, and growth kinetics of the Streptococcus mutans biofilm were assessed by SEM, confocal laser scanning microscopy, and the counting of colony-forming units (CFUs), respectively. RESULTS SEM images of LF-treated enamel showed an intact surface compared with other groups. Nanohardness (GPa) for LF, F, L and W were 1.43±0.17, 1.01±0.11, 1.04±0.13 and 0.73±0.14, respectively (p<0.001; LF>F, L>W). Their lesion depths (µm) were 46±8, 52±6, 88±13 and 111±9, respectively (p<0.001; LF, F<L<W). SEM showed few bacteria for LF and F compared with other groups. Their dead-live ratio were 1.67±0.13, 1.60±0.15, 0.39±0.05 and 0.32±0.05, respectively (p<0.001; LF, F>L>W). Log CFUs for LF, F, L and W were 4.2±0.3, 4.5±0.2, 7.9±0.3 and 9.4±0.2, respectively (p<0.05; LF<F<L<W). Two-way ANOVA analysis revealed an interaction effect on nanohardness and Log CFUs between the laser irradiation and SDF treatment (p<0.001). CONCLUSION This study showed a superior caries preventive effect of a combined treatment of the diode laser and SDF. Because diode laser and SDF are affordable and readily available, clinicians can provide this treatment to their patients for caries prevention. CLINICAL SIGNIFICANCE STATEMENT Diode lasers are handy, afforable and readily avaliable to clinicians. This study provides information of use of 445 nm diode laser for caries prevetion. The laser irradiation hopefully can be added before conventional topical SDF application.
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Affiliation(s)
- Vicky Wenqing Xue
- School of Dentistry, Shenzhen University Health Science Center, Shenzhen, 518000, China; Faculty of Dentistry, The University of Hong Kong, Hong Kong, 999077, China
| | - Iris Xiaoxue Yin
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, 999077, China
| | - John Yun Niu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, 999077, China
| | - Edward Chin Man Lo
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, 999077, China
| | - Chun Hung Chu
- Faculty of Dentistry, The University of Hong Kong, Hong Kong, 999077, China.
| | - Irene Shuping Zhao
- School of Dentistry, Shenzhen University Health Science Center, Shenzhen, 518000, China.
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Panariello BHD, Cavichioli EAM, Sochacki SF, Gandini Junior LG, Duarte S. Blue light & chlorhexidine therapies on Streptococcus mutans biofilm and its regrowth on an in vitro orthodontic model. Am J Orthod Dentofacial Orthop 2021; 161:103-114. [PMID: 34452788 DOI: 10.1016/j.ajodo.2020.06.050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 05/01/2020] [Accepted: 06/01/2020] [Indexed: 11/17/2022]
Abstract
INTRODUCTION Fixed orthodontic appliances create areas of stagnation for dental biofilms and make it difficult to clean the teeth; therefore, there is a risk of developing incipient caries lesions during the orthodontic treatment. The objective of this study is to determine if the combination of 2 different therapies, phototherapy by blue light (BL) and the antimicrobial 0.12% chlorhexidine (CHX) on enamel, orthodontic brackets, and elastics, would reduce or inhibit mature Streptococcus mutans biofilms and their regrowth on these substrates 24 hours after the application of the treatment; and if this treatment would interfere with bracket adhesion to the enamel. METHODS Biofilms of S. mutans UA159 were formed for 5-days over samples composed of a bovine enamel, orthodontic bracket, and orthodontic elastic. Then, the specimens were treated with 0.89% NaCl for 1 minute, BL for 12 minutes (72 J/cm2), 0.12% CHX for 1 minute, and BL for 12 minutes, followed by 0.12% CHX for 1 minute (BL+CHX). Biofilm was evaluated by colonies forming units and dry weight immediately after treatments and 24 hours after treatments (regrowth). The pH of the spent media was measured on the fifth and sixth days. Biofilm formation on the samples after the treatments and regrowth was visually evaluated by confocal laser scanning microscopy. Shear bond strength (SBS) between bracket and enamel was evaluated using a universal testing machine at a crosshead speed of 1 mm/min. After bonding, specimens were thermocycled (500× at 5-55°C), treated, and thermocycled again. RESULTS After 5 days of biofilm formation, BL+CHX significantly reduced the bacterial viability on enamel compared with NaCl (P = 0.004) and BL (P = 0.014). For bracket and elastic, all the treatments resulted in similar bacterial viability (P ≥0.081). In the regrowth, CHX and BL+CHX significantly reduced the bacterial viability in the enamel compared with the NaCl (P ≤0.015) and BL (P ≤0.013). For bracket, BL+CHX significantly reduced the bacterial viability compared with NaCl (P = 0.008) and BL (P = 0.009). For the elastic, BL+CHX eliminated the biofilms from the substrate. CHX and BL+CHX significantly reduced the bacterial viability 24 hours after treatment for all substrates (P ≤0.05). The media pH significantly increased when samples were treated with CHX and BL+CHX (P ≤0.001). Confocal laser scanning microscopy images visually showed an abundant quantity of red cells in the samples treated with BL+CHX. There was no difference in the SBS between the treatments (P ≥0.932). CONCLUSIONS The association between BL and CHX reduced S. mutans biofilm and its regrowth on an in vitro orthodontic model and did not influence the bonding strength between bracket and enamel.
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Affiliation(s)
- Beatriz H D Panariello
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, Ind
| | - Eder A M Cavichioli
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry at Araraquara, UNESP São Paulo State University, Araraquara, São Paulo, Brazil
| | - Sabrina Feitosa Sochacki
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, Ind
| | - Luiz Gonzaga Gandini Junior
- Department of Orthodontics and Pediatric Dentistry, School of Dentistry at Araraquara, UNESP São Paulo State University, Araraquara, São Paulo, Brazil
| | - Simone Duarte
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, Ind.
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Biofilm viability checker: An open-source tool for automated biofilm viability analysis from confocal microscopy images. NPJ Biofilms Microbiomes 2021; 7:44. [PMID: 33990612 PMCID: PMC8121819 DOI: 10.1038/s41522-021-00214-7] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 03/12/2021] [Indexed: 12/15/2022] Open
Abstract
Quantifying biofilm formation on surfaces is challenging because traditional microbiological methods, such as total colony-forming units (CFUs), often rely on manual counting. These are laborious, resource intensive techniques, more susceptible to human error. Confocal laser scanning microscopy (CLSM) is a high-resolution technique that allows 3D visualisation of biofilm architecture. In combination with a live/dead stain, it can be used to quantify biofilm viability on both transparent and opaque surfaces. However, there is little consensus on the appropriate methodology to apply in confocal micrograph processing. In this study, we report the development of an image analysis approach to repeatably quantify biofilm viability and surface coverage. We also demonstrate its use for a range of bacterial species and translational applications. This protocol has been created with ease of use and accessibility in mind, to enable researchers who do not specialise in computational techniques to be confident in applying these methods to analyse biofilm micrographs. Furthermore, the simplicity of the method enables the user to adapt it for their bespoke needs. Validation experiments demonstrate the automated analysis is robust and accurate across a range of bacterial species and an improvement on traditional microbiological analysis. Furthermore, application to translational case studies show the automated method is a reliable measurement of biomass and cell viability. This approach will ensure image analysis is an accessible option for those in the microbiology and biomaterials field, improve current detection approaches and ultimately support the development of novel strategies for preventing biofilm formation by ensuring comparability across studies.
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Potential for direct application of blue light for photo-disinfection of dentine. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2021; 215:112123. [PMID: 33454542 DOI: 10.1016/j.jphotobiol.2021.112123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Revised: 10/31/2020] [Accepted: 01/05/2021] [Indexed: 12/24/2022]
Abstract
The direct application of light for photo-disinfection potentially provides a safe and novel modality to inhibit or eliminate cariogenic bacteria residing upon and within dentine. This study aimed to both; characterize the pattern of transmission of 405 nm light through molar dentine at different tooth locations, as well as, determine the irradiation parameters that are antibacterial for Streptococcus mutans under various growth conditions, including lawns, planktonic cultures, and biofilms. To determine the amount of light (405 nm) transmitted at different anatomical tooth locations; irradiance values were recorded after blue light (470-4054 mW/cm2) had traversed through occlusal, oblique, and buccal dentine sections; and three thicknesses - 1, 2 and 3 mm were investigated. To determine tubular density; scanning electron micrographs from 2 mm outer (dentine-enamel junction) and inner (pulp) dentine sections were analysed. For photo-disinfection studies; S. mutans was irradiated using the same 405 nm wavelength light at a range of doses (110-1254 J/cm2) in both biofilm and planktonic cultures. The inhibitory effect of the irradiation on bacterial lawns was compared by measuring zones of inhibition; and for planktonic cultures both spectrophotometric and colony forming unit (CFU) assays were performed. A live/dead staining assay was utilised to determine the effect of irradiation on bacterial viability in mature biofilms. Data indicated that increasing dentine thickness decreased light transmission significantly irrespective of its orientation. Occlusal and oblique samples exhibited higher transmission compared with buccal dentine. Oblique dentine 405 nm light transmission was comparable with that of occlusal dentine independent of section thickness. An increased tubule density directly positively correlated with light transmission. Irradiation at 405 nm inhibited S. mutans growth in both biofilm and planktonic cultures and a dose response relationship was observed. Irradiation at doses of 340 and 831 J/cm2 led to significant reductions in bacterial growth and viability; as determined by CFU counting and live/dead staining. Data suggests that phototherapy approaches utilising a 405 nm wavelength have therapeutic potential to limit cariogenic bacterial infections both at the surface and within dentine.
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Lusche I, Dirk C, Frentzen M, Meister J. Cavity Disinfection With a 445 nm Diode Laser Within the Scope of Restorative Therapy - A Pilot Study. J Lasers Med Sci 2021; 11:417-426. [PMID: 33425292 DOI: 10.34172/jlms.2020.66] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Introduction: Cavity disinfection is necessary to prevent a progressive infection of the crown dentin and pulp. Increasing intolerance and resistance to antiseptics and antibiotics as well as the controversy over the effects of those on the dental hard tissue and composite have prompted the investigation of alternative treatment options. The objective of this pilot study is to evaluate the antibacterial potential of a diode laser with a wavelength of 445 nm in the cavity preparation using the bacterium Streptococcus salivarius associated with caries in conjunction with the characteristics and influences of dentin on light transmission. Methods: The bactericidal effect of the laser irradiation was determined in culture experiments by using caries-free human dentin samples on bacteria-inoculated agar. For this, dentin discs (horizontally cut coronal dentin) of 500 µm and 1000 µm thicknesses were produced and irradiated with the laser with irradiation parameters of 0.7-1 W in a cw-mode and exposure times of between 5-30 s. Based on the different sample thicknesses, the penetration depth effect of the irradiation was ascertained after the subsequent incubation of the bacteria-inoculated agar. Additional influential parameters on the irradiation transmission were investigated, including surface moisture, tooth color as well as the presence of a smear layer on the dentin surface. Results: The optical transmission values of the laser radiation for dentin were significantly dependent on the sample thickness (P = 0.006) as well as its moisture content (P = 0.013) and were independent of the presence of a smear layer. There was a 40% reduction in bacteria after the radiography of the 500-µm-thick dentin samples, which was shown as the lowest laser dose (443 J/cm2). Conclusion: These findings indicate that the diode laser with light emission at a wavelength of 445 nm is interesting for the supportive cavity disinfection within the scope of caries therapy and show potential for clinical applications.
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Affiliation(s)
- Inés Lusche
- Department of Operative and Preventive Dentistry, Bonn University, Welschnonnenstrasse 17, D-53111 Bonn, Germany
| | - Cornelius Dirk
- Oral Technology, Bonn University, Wilhelmsplatz 5, 53111 Bonn, Germany
| | - Matthias Frentzen
- Department of Operative and Preventive Dentistry, Bonn University, Welschnonnenstrasse 17, D-53111 Bonn, Germany.,Center of Dento-Maxillo-Facial Medicine, Bonn University, Welschnonnenstrasse 17, D-53111 Bonn, Germany
| | - Jörg Meister
- Center of Dento-Maxillo-Facial Medicine, Bonn University, Welschnonnenstrasse 17, D-53111 Bonn, Germany.,Center of Applied Medical Laser Research and Biomedical Optics (AMLaReBO), Bonn University, Welschnonnenstrasse 17, D-53111 Bonn, Germany.,Laser Application in Medical Sciences Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Yuan S, Qi M, Peng Q, Huang G, Liu J, Xu Z, Gong X, Zhang G. Adaptive behaviors of planktonic Pseudomonas aeruginosa in response to the surface-deposited dead siblings. Colloids Surf B Biointerfaces 2020; 197:111408. [PMID: 33099147 DOI: 10.1016/j.colsurfb.2020.111408] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/23/2020] [Accepted: 10/08/2020] [Indexed: 11/27/2022]
Abstract
In this study, the 3D motion behaviors and the underlying adaptation mechanism of planktonic Pseudomonas aeruginosa (PAO1) in response to the deposited dead siblings nearby were explored. Utilizing a real-time 3D tracking technique, digital holographic microscopy (DHM), we demonstrate that planktonic cells near the surface covered with dead siblings have a lower density and a reduced 3D velocity compared with those upon viable ones. As a sign of chemosensory responses, bacteria swimming near the dead siblings exhibit increase in frequency of the 'flick' motion. Transcriptomic analysis by RNA-seq reveals an upregulated expression of dgcM and dgcE inhibited the movement of PAO1, accompanied by increased transcriptional levels of the virulence factor-related genes hcp1, clpV1, and vgrG1. Moreover, the decrease in l-glutamate and the increase in succinic acid in the metabolites of the dead bacteria layer promote the dispersion of planktonic bacteria. As a result, the dead siblings on a surface inhibit the bacterial accumulation and activate the adaptive defensive responses of planktonic PAO1 in the vicinity.
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Affiliation(s)
- Shuo Yuan
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Meng Qi
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Qingmei Peng
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Gui Huang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Jun Liu
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Zhenbo Xu
- School of Food Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
| | - Xiangjun Gong
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China; Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates (South China University of Technology), PR China.
| | - Guangzhao Zhang
- Faculty of Materials Science and Engineering, South China University of Technology, Guangzhou 510640, PR China
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Molina R, López G, Coniglio A, Furlan A, Mora V, Rosas S, Cassán F. Day and blue light modify growth, cell physiology and indole-3-acetic acid production of Azospirillum brasilense Az39 under planktonic growth conditions. J Appl Microbiol 2020; 130:1671-1683. [PMID: 32979295 DOI: 10.1111/jam.14869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 09/19/2020] [Accepted: 09/22/2020] [Indexed: 11/28/2022]
Abstract
AIM In this work, we evaluated the effects of light on growth, cell physiology and stress response of Azospirillum brasilense Az39, a non-photosynthetic rhizobacteria, under planktonic growth conditions. METHODS AND RESULTS Exponential cultures of Az39 were exposed to blue (BL), red (RL) and daylight (DL) or maintained in darkness for 24, 48 and 72 h. The biomass production and indole 3-acetic acid (IAA) biosynthesis increased by exposition to DL. Conversely, BL decreased IAA concentration through a direct effect on the molecule. The DL increased superoxide dismutase activity, hydrogen peroxide and thiobarbituric acid reactive substances levels, but the last one was also increased by BL. Both DL and BL increased cell aggregation but only BL increased biofilm formation. CONCLUSIONS We demonstrated that both BL and DL are stress effectors for A. brasilense Az39 under planktonic growth conditions. The DL increased biomass production, IAA biosynthesis and bacterial response to stress, whereas BL induced cell aggregation and biofilms formation, but decreased the IAA concentration by photooxidation. SIGNIFICANCE AND IMPACT OF THE STUDY Blue light and DL changes growth capacity, cell physiology and plant growth promotion ability of A. brasilense Az39 and these changes could be considered to improve the production and functionality of biofertilizers.
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Affiliation(s)
- R Molina
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - G López
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - A Coniglio
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - A Furlan
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - V Mora
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - S Rosas
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
| | - F Cassán
- Laboratorio de Fisiología Vegetal y de la Interacción Planta-microorganismo, Instituto de Investigaciones Agrobiotecnológicas (INIAB-CONICET), Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina
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11
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Galo IDC, Lima BED, Santos TG, Braoios A, Prado RP, Santos WGD. Staphylococcus aureus growth delay after exposure to low fluencies of blue light (470 nm). BRAZ J BIOL 2020; 81:370-376. [PMID: 32490986 DOI: 10.1590/1519-6984.226473] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 11/09/2019] [Indexed: 11/22/2022] Open
Abstract
Antibiotic resistance is one of the greatest challenges to treat bacterial infections worldwide, leading to increase in medical expenses, prolonged hospital stay and increased mortality. The use of blue light has been suggested as an innovative alternative to overcome this problem. In this study we analyzed the antibacterial effect of blue light using low emission parameters on Staphylococcus aureus cultures. In vitro bacterial cultures were used in two experimental approaches. The first approach included single or fractionated blue light application provided by LED emitters (470 nm), with the following fluencies: 16.29, 27.16 and 54.32 J/cm2. For the second approach a power LED (470 nm) was used to deliver 54.32 J/cm2 fractionated in 3 applications. Our results demonstrated that bacterial cultures exposed to fractionated blue light radiation exhibited significantly smaller sizes colonies than the control group after 24 h incubation, however the affected bacteria were able to adapt and continue to proliferate after prolonged incubation time. We could conclude that the hypothetical clinical use of low fluencies of blue light as an antibacterial treatment is risky, since its action is not definitive and proves to be ineffective at least for the strain used in this study.
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Affiliation(s)
- I D C Galo
- Unidade Acadêmica Especial de Ciências da Saúde, Programa de Pós-graduação em Ciências Aplicadas à Saúde, Universidade Federal de Goiás - UFG, Regional Jataí, Câmpus Jatobá, Cidade Universitária, BR 364, Km 195, 3800, CEP 75801-615, Jataí, GO, Brasil
| | - B E De Lima
- Unidade Acadêmica Especial de Ciências da Saúde, Programa de Pós-graduação em Ciências Aplicadas à Saúde, Universidade Federal de Goiás - UFG, Regional Jataí, Câmpus Jatobá, Cidade Universitária, BR 364, Km 195, 3800, CEP 75801-615, Jataí, GO, Brasil
| | - T G Santos
- Unidade Acadêmica Especial de Ciências da Saúde, Programa de Pós-graduação em Ciências Aplicadas à Saúde, Universidade Federal de Goiás - UFG, Regional Jataí, Câmpus Jatobá, Cidade Universitária, BR 364, Km 195, 3800, CEP 75801-615, Jataí, GO, Brasil
| | - A Braoios
- Unidade Acadêmica Especial de Ciências da Saúde, Programa de Pós-graduação em Ciências Aplicadas à Saúde, Universidade Federal de Goiás - UFG, Regional Jataí, Câmpus Jatobá, Cidade Universitária, BR 364, Km 195, 3800, CEP 75801-615, Jataí, GO, Brasil
| | - R P Prado
- Departamento de Medicina, Universidade Federal de Goiás - UFG, Regional Catalão, Campus II, Av. Castelo Branco, s/n, Setor Universitário, CEP 75704-020, Catalão, GO, Brasil
| | - W G Dos Santos
- Unidade Acadêmica Especial de Ciências da Saúde, Programa de Pós-graduação em Ciências Aplicadas à Saúde, Universidade Federal de Goiás - UFG, Regional Jataí, Câmpus Jatobá, Cidade Universitária, BR 364, Km 195, 3800, CEP 75801-615, Jataí, GO, Brasil
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12
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Esteban Florez FL, Hiers RD, Zhao Y, Merritt J, Rondinone AJ, Khajotia SS. Optimization of a real-time high-throughput assay for assessment of Streptococcus mutans metabolism and screening of antibacterial dental adhesives. Dent Mater 2020; 36:353-365. [PMID: 31952798 PMCID: PMC7042092 DOI: 10.1016/j.dental.2019.12.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Revised: 09/17/2019] [Accepted: 12/18/2019] [Indexed: 12/25/2022]
Abstract
Objective. The present work shows the optimization of a high-throughput bioluminescence assay to assess the metabolism of intact Streptococcus mutans biofilms and its utility as a screening method for nanofilled antibacterial dental materials. Methods. The assay was optimized by monitoring changes in bioluminescence mediated by variation of the experimental parameters investigated (growth media and sucrose concentration, inoculum:D-Luciferin ratio, dilution factor, inoculum volume, luminescence wavelength, replicate and luciferase metabolic activity). Confocal microscopy was then used to demonstrate the impact of biofilm growth conditions on the 3-D distribution of extracellular polymeric substance (EPS) within Streptococcus mutans biofilms and its implications as confounding factors in high-throughput studies (HTS). Results. Relative Luminescence Unit (RLU) values from the HTS optimization were analyzed by multivariate ANOVA (α = 0.05) and coefficients of variation, whereas data from 3-D structural parameters and RLU values of biofilms grown on experimental antibacterial dental adhesive resins were analyzed using General Linear Models and Student–Newman–Keuls post hoc tests (α = 0.05). Confocal microscopy demonstrated that biofilm growth conditions significantly influenced the quantity and distribution of EPS within the 3-D structures of the biofilms. An optimized HTS bioluminescence assay was developed and its applicability as a screening method in dentistry was demonstrated using nanofilled experimental antibacterial dental adhesive resins. Significance. The present study is anticipated to positively impact the direction of future biofilm research in dentistry, because it offers fundamental information for the design of metabolic-based assays, increases the current levels of standardization and reproducibility while offering a tool to decrease intra-study variability.
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Affiliation(s)
- Fernando Luis Esteban Florez
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials, College of Dentistry, 1201 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA.
| | - Rochelle Denise Hiers
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials, College of Dentistry, 1201 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA.
| | - Yan Zhao
- The University of Oklahoma Health Sciences Center, Department of Biostatistics and Epidemiology, College of Public Health, 801 NE 13th Street, Oklahoma City, OK, 73126, USA.
| | - Justin Merritt
- Oregon Health & Science University, Department of Restorative Dentistry, School of Dentistry, MRB424, 3181 SW Sam Jackson Park Rd., Portland, OR, 97239, USA.
| | - Adam Justin Rondinone
- Oak Ridge National Laboratory, Center for Nanophase Materials Sciences, Oak Ridge, TN, 37831, USA.
| | - Sharukh Soli Khajotia
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials, College of Dentistry, 1201 N. Stonewall Avenue, Oklahoma City, OK, 73117, USA.
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13
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Felix Gomez GG, Lippert F, Ando M, Zandona AF, Eckert GJ, Gregory RL. Photoinhibition of Streptococcus mutans Biofilm-Induced Lesions in Human Dentin by Violet-Blue Light. Dent J (Basel) 2019; 7:dj7040113. [PMID: 31835833 PMCID: PMC6960986 DOI: 10.3390/dj7040113] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 09/29/2019] [Accepted: 11/28/2019] [Indexed: 01/13/2023] Open
Abstract
This in vitro study determined the effectiveness of violet-blue light on Streptococcus mutans (UA159) biofilm induced dentinal lesions. Biofilm was formed on human dentin specimens in a 96-well microtiter plate and incubated for 13 h in the presence of tryptic soy broth (TSB) or TSB supplemented with 1% sucrose (TSBS). Violet-blue light (405 nm) from quantitative light-induced fluorescence (QLFTM) was used to irradiate the biofilm. Supernatant liquid was removed, and the biofilm was irradiated continuously with QLF for 5 min twice daily with an interval of 6 h for 5 d, except with one treatment on the final day. Colony forming units (CFU) of the treated biofilm, changes in fluorescence (∆F; QLF-Digital BiluminatorTM), lesion depth (L), and integrated mineral loss (∆Z; both transverse microradiography) were quantified at the end of the fifth day. Statistical analysis used analysis of variance (ANOVA), testing at a 5% significance level. In the violet-blue light irradiated groups, there was a significant reduction (p < 0.05) of bacterial viability (CFU) of S. mutans with TSB and TSBS. Violet-blue light irradiation resulted in the reduction of ∆F and L of the dentinal surface with TSBS. These results indicate that violet-blue light has the capacity to reduce S. mutans cell numbers.
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Affiliation(s)
- Grace Gomez Felix Gomez
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN 46202, USA;
| | - Frank Lippert
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, IN 46202, USA; (F.L.); (M.A.)
| | - Masatoshi Ando
- Department of Cariology, Operative Dentistry and Dental Public Health, Indiana University School of Dentistry, Indianapolis, IN 46202, USA; (F.L.); (M.A.)
| | - Andrea F. Zandona
- Department of Comprehensive Care, Tufts School of Dental Medicine, Boston, MA 02111, USA;
| | - George J. Eckert
- Department of Biostatistics, Indiana University, Indianapolis, IN 46202, USA
| | - Richard L. Gregory
- Department of Biomedical Sciences and Comprehensive Care, Indiana University School of Dentistry, Indianapolis, IN 46202, USA;
- Correspondence: ; Tel.: +1-317-274-9949
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14
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Exposure of Streptococcus mutans and Streptococcus sanguinis to blue light in an oral biofilm model. Lasers Med Sci 2019; 35:709-718. [PMID: 31713778 DOI: 10.1007/s10103-019-02903-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 10/18/2019] [Indexed: 10/25/2022]
Abstract
The potential anti-cariogenic effect of blue light was evaluated using an oral biofilm model. Two species, Streptococcus mutans and Streptococcus sanguinis, were cultivated ex vivo on bovine enamel blocks for 24 h, either separately or mixed together, then exposed to blue light (wavelengths 400-500 nm) using 112 J/cm2. Twenty four or 48 h after exposure to light the biofilm structure and biomass were characterized and quantified using SEM and qPCR, respectively. Bacterial viability was analyzed by CLSM using live/dead bacterial staining. Gene expression was examined by RT-qPCR. After exposure to light, S. mutans biomass in mono-species biofilm was increased mainly by dead bacteria, relative to control. However, the bacterial biomass of S. mutans when grown in mixed biofilm and of S. sanguinis in mono-species biofilm was reduced after light exposure, with no significant change in viability when compared to control. Furthermore, when grown separately, an upregulation of gene expression related to biofilm formation of S. mutans, and downregulation of similar genes of S. sanguinis, were measured 24 h after exposure to blue light. However, in mixed biofilm, a downregulation of those genes in both species was observed, although not significant in S. mutans. In conclusion, blue light seems to effectively alter the bacterial biomass by reducing the viability and virulence characteristics in both bacterial species and may promote the anti-cariogenic balance between them, when grown in a mixed biofilm. Therefore, exposure of oral biofilm to blue light has the potential to serve as a complementary approach in preventive dentistry.
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15
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Shany-Kdoshim S, Polak D, Houri-Haddad Y, Feuerstein O. Killing mechanism of bacteria within multi-species biofilm by blue light. J Oral Microbiol 2019; 11:1628577. [PMID: 31275529 PMCID: PMC6598489 DOI: 10.1080/20002297.2019.1628577] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 05/24/2019] [Accepted: 05/31/2019] [Indexed: 01/10/2023] Open
Abstract
Objectives: The aim of the study was to characterize the immediate and delayed effects of non-coherent blue-light treatment on the composition and viability of an in vitro biofilm composed of anaerobic multispecies, as well as the mechanisms involved. Methods: A multispecies biofilm was constructed of Streptococcus sanguinis, Actinomyces naeslundii, Porphyromonas gingivalis and Fusobacterium nucleatum, test groups were exposed to blue light. The multispecies biofilm was explored with a newly developed method based on flow cytometry and confocal microscopy. The involvement of the paracrine pathway in the phototoxic mechanism was investigated by a crossover of the supernatants between mono-species P. gingivalis and F. nucleatum biofilms. Results: Blue light led to a reduction of about 50% in the viable pathogenic bacteria P. gingivalis and F. nucleatum, vs that in the non-exposed biofilm. Biofilm thickness was also reduced by 50%. The phototoxic effect of blue light on mono-species biofilm was observed in P. gingivalis, whereas F. nucleatum biofilm was unaffected. A lethal effect was obtained when the supernatant of P. gingivalis biofilm previously exposed to blue light was added to the F. nucleatum biofilm. The effect was circumvented by the addition of reactive oxygen species (ROS) scavengers to the supernatant. Conclusion: Blue-light has an impact on the bacterial composition and viability of the multispecies biofilm. The phototoxic effect of blue light on P. gingivalis in biofilm was induced directly and on F. nucleatum via ROS mediators of the paracrine pathway. This phenomenon may lead to a novel approach for 'replacement therapy,' resulting in a less periodonto-pathogenic biofilm.
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Affiliation(s)
- Sharon Shany-Kdoshim
- Department of Periodontology, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
| | - David Polak
- Department of Periodontology, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
| | - Yael Houri-Haddad
- Department of Prosthodontics, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
| | - Osnat Feuerstein
- Department of Prosthodontics, Hebrew University-Hadassah Faculty of Dental Medicine, Jerusalem, Israel
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16
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Ponomareva AL, Buzoleva LS, Bogatyrenko EA. Abiotic Environmental Factors Affecting the Formation of Microbial Biofilms. BIOL BULL+ 2018. [DOI: 10.1134/s106235901805014x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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17
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Esteban Florez FL, Hiers RD, Larson P, Johnson M, O'Rear E, Rondinone AJ, Khajotia SS. Antibacterial dental adhesive resins containing nitrogen-doped titanium dioxide nanoparticles. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2018; 93:931-943. [PMID: 30274130 DOI: 10.1016/j.msec.2018.08.060] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 04/25/2018] [Accepted: 08/29/2018] [Indexed: 10/28/2022]
Abstract
The development of dental adhesive resins with long-lasting antibacterial properties is a possible solution to overcome the problem of secondary caries in modern adhesive dentistry. OBJECTIVES (i) Synthesis and characterization of nitrogen-doped titanium dioxide nanoparticles (N_TiO2), (ii) topographical, compositional and wettability characterization of thin-films (unaltered and experimental) and, (iii) antibacterial efficacy of N_TiO2-containing dental adhesives against Streptococcus mutans biofilms. MATERIALS AND METHODS Nanoparticles were synthesized and characterized using different techniques. Specimens (diameter = 12 mm, thickness ≅ 15 μm) of OptiBond Solo Plus (Kerr Corp., USA) and experimental adhesives [50, 67 and 80% (v/v)] were fabricated, photopolymerized (1000 mW/cm2, 1 min) and UV-sterilized (254 nm, 800,000 μJ/cm2) for microscopy, spectroscopy, wettability and antibacterial testing. Wettability was assessed with a contact angle goniometer by dispensing water droplets (2 μL) onto four random locations of each specimen (16 drops/group). Drop profiles were recorded (1 min, 25 frames/s, 37 °C) and contact angles were calculated at time = 0 s (θINITIAL) and time = 59 s (θFINAL). Antibacterial testing was performed by growing S. mutans (UA159-ldh, JM10) biofilms for either 3 or 24 h (anaerobic conditions, 37 °C) with or without continuous light irradiation (410 ± 10 nm, 3 h = 38.75 J/cm2, 24 h = 310.07 J/cm2) against the surfaces of sterile specimens. RESULTS N_TiO2 was successfully prepared using solvothermal methods. Doped-nanoparticles displayed higher light absorption levels when compared to undoped titania. Experimental adhesives demonstrated superior antibacterial efficacy in dark conditions. CONCLUSIONS The findings presented herein suggest that N_TiO2 is a feasible antibacterial agent against cariogenic biofilms.
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Affiliation(s)
- Fernando Luis Esteban Florez
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials College of Dentistry, 1201 North Stonewall Avenue, Room 146, Oklahoma City, OK 73117, USA.
| | - Rochelle Denise Hiers
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials College of Dentistry, 1201 North Stonewall Avenue, Room 146, Oklahoma City, OK 73117, USA.
| | - Preston Larson
- The University of Oklahoma, Samuel Roberts Noble Microscopy Laboratory, 770 Van Vleet Oval, Norman, OK 73019, USA.
| | - Matthew Johnson
- The University of Oklahoma, Department of Physics and Astronomy, 440 West Brooks Street, Room 129, Norman, OK 73019, USA
| | - Edgar O'Rear
- The University of Oklahoma, School of Chemical, Biological and Materials Engineering, 100 East Boyd, T-301, Sarkeys Energy Center, Norman, OK 73019, USA.
| | - Adam J Rondinone
- Oak Ridge National Laboratory, Center for Nanophase Materials Sciences, Oak Ridge, TN 37831, USA.
| | - Sharukh Soli Khajotia
- The University of Oklahoma Health Sciences Center, Department of Restorative Sciences, Division of Dental Biomaterials College of Dentistry, 1201 North Stonewall Avenue, Room 146, Oklahoma City, OK 73117, USA.
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18
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Gomez GF, Huang R, Eckert G, Gregory RL. Effect of phototherapy on the metabolism of Streptococcus mutans biofilm based on a colorimetric tetrazolium assay. J Oral Sci 2018; 60:242-246. [PMID: 29925708 DOI: 10.2334/josnusd.17-0203] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
The aim of this in vitro study was to determine the effect of violet-blue light on the metabolic activity of early Streptococcus mutans biofilm, reincubated at 0, 2, and 6 h after 5 min of violet-blue light treatment. S. mutans UA159 biofilm cells were cultured for 12 to 16 h in microtiter plates with Tryptic Soy broth (TSB) or TSB with 1% sucrose (TSBS) and irradiated with violet-blue light for 5 min. After irradiation, the plates were reincubated at 37°C for 0, 2, or 6 h in 5% CO2. Colorimetric tetrazolium salt reduction assay was used to investigate bacterial metabolic activity. Mixed model ANOVA was used to find the difference between the violet-blue light treated and nontreated groups. Bacterial metabolic activity was significantly lower in the violet-blue light group for TSB than in the nontreated group (P < 0.0001) regardless of recovery time. However, the differences between metabolic activity in the treated groups without sucrose decreased over time. For TSBS, metabolic activity was significantly lower with violet-blue light at 0 and 2 h. Violet-blue light inhibited the metabolic activity of S. mutans biofilm cells in the light-treated group. This finding may present a unique treatment method for patients with active caries.
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Affiliation(s)
- Grace F Gomez
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry
| | - Ruijie Huang
- Department of Pediatric Dentistry, West China School of Stomatology, Sichuan University
| | - George Eckert
- Department of Biostatistics, Indiana University School of Medicine
| | - Richard L Gregory
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry
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19
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Effect of Violet-Blue Light on Streptococcus mutans-Induced Enamel Demineralization. Dent J (Basel) 2018; 6:dj6020006. [PMID: 29565266 PMCID: PMC6023538 DOI: 10.3390/dj6020006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2018] [Revised: 03/15/2018] [Accepted: 03/16/2018] [Indexed: 11/26/2022] Open
Abstract
Background: This in vitro study determined the effectiveness of violet-blue light (405 nm) on inhibiting Streptococcus mutans-induced enamel demineralization. Materials and Methods: S. mutans UA159 biofilm was grown on human enamel specimens for 13 h in 5% CO2 at 37 °C with/without 1% sucrose. Wet biofilm was treated twice daily with violet-blue light for five minutes over five days. A six-hour reincubation was included daily between treatments excluding the final day. Biofilms were harvested and colony forming units (CFU) were quantitated. Lesion depth (L) and mineral loss (∆Z) were quantified using transverse microradiography (TMR). Quantitative light-induced fluorescence Biluminator (QLF-D) was used to determine mean fluorescence loss. Data were analyzed using one-way analysis of variance (ANOVA) to compare differences in means. Results: The results demonstrated a significant reduction in CFUs between treated and non-treated groups grown with/without 1% sucrose. ∆Z was significantly reduced for specimens exposed to biofilms grown without sucrose with violet-blue light. There was only a trend on reduction of ∆Z with sucrose and with L on both groups. There were no differences in fluorescence-derived parameters between the groups. Conclusions: Within the limitations of the study, the results indicate that violet-blue light can serve as an adjunct prophylactic treatment for reducing S. mutans biofilm formation and enamel mineral loss.
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20
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Anti-biofilm effect of 405-nm LEDs against Listeria monocytogenes in simulated ready-to-eat fresh salmon storage conditions. Food Control 2018. [DOI: 10.1016/j.foodcont.2017.09.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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21
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Wang Y, Wang Y, Wang Y, Murray CK, Hamblin MR, Hooper DC, Dai T. Antimicrobial blue light inactivation of pathogenic microbes: State of the art. Drug Resist Updat 2017; 33-35:1-22. [PMID: 29145971 DOI: 10.1016/j.drup.2017.10.002] [Citation(s) in RCA: 167] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 06/28/2017] [Accepted: 10/02/2017] [Indexed: 12/20/2022]
Abstract
As an innovative non-antibiotic approach, antimicrobial blue light in the spectrum of 400-470nm has demonstrated its intrinsic antimicrobial properties resulting from the presence of endogenous photosensitizing chromophores in pathogenic microbes and, subsequently, its promise as a counteracter of antibiotic resistance. Since we published our last review of antimicrobial blue light in 2012, there have been a substantial number of new studies reported in this area. Here we provide an updated overview of the findings from the new studies over the past 5 years, including the efficacy of antimicrobial blue light inactivation of different microbes, its mechanism of action, synergism of antimicrobial blue light with other angents, its effect on host cells and tissues, the potential development of resistance to antimicrobial blue light by microbes, and a novel interstitial delivery approach of antimicrobial blue light. The potential new applications of antimicrobial blue light are also discussed.
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Affiliation(s)
- Yucheng Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Cancer Center, Aviation General Hospital, Beijing, China; Department of Medical Oncology, Beijing Institute of Translational Medicine, Chinese Academy of Sciences, Beijing, China
| | - Ying Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Laser Medicine, Chinese PLA General Hospital, Beijing, China
| | - Yuguang Wang
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Center of Digital Dentistry, School and Hospital of Stomatology, Peking University, Beijing, China
| | - Clinton K Murray
- Infectious Disease Service, San Antonio Military Medical Center, JBSA-Fort Sam Houston, TX, USA
| | - Michael R Hamblin
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - David C Hooper
- Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Tianhong Dai
- Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
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Antimicrobial efficacy of irradiation with visible light on oral bacteria in vitro: a systematic review. Future Med Chem 2017; 9:1557-1574. [PMID: 28792235 DOI: 10.4155/fmc-2017-0051] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
AIM Resistances to antibiotics employed for treatment of infectious diseases have increased to alarming numbers making it more and more difficult to treat diseases caused by microorganisms resistant to common antibiotics. Consequently, novel methods for successful inactivation of pathogens are required. In this instance, one alternative could be application of light for treatment of topical infections. Antimicrobial properties of UV light are well documented, but due to its DNA-damaging properties use for medical purposes is limited. In contrast, irradiation with visible light may be more promising. METHODS Literature was systematically screened for research concerning inactivation of main oral bacterial species by means of visible light. RESULTS Inactivation of bacterial species, especially pigmented ones, in planktonic state showed promising results. There is a lack of research examining the situation when organized as biofilms. CONCLUSION More research concerning situation in a biofilm state is required.
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Gomez GF, Huang R, MacPherson M, Ferreira Zandona AG, Gregory RL. Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light. Curr Microbiol 2016; 73:426-433. [PMID: 27278805 DOI: 10.1007/s00284-016-1075-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 04/23/2016] [Indexed: 11/26/2022]
Abstract
Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one of the methods used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using tryptic soy broth (TSB) or TSB with 1 % sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37 °C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (P < 0.05) decrease compared to the non-treated groups after the 2 or 6 h recovery period. Growth rates of planktonic and biofilm cells indicated a significant reduction in the growth rate of the violet-blue light-treated groups grown in TSB and TSBS. Biofilm viability assays confirmed a statistically significant difference between violet-blue light-treated and non-treated groups in TSB and TSBS. Visible violet-blue light of the electromagnetic spectrum has the ability to inhibit S. mutans growth and reduce the formation of S. mutans biofilm. This in vitro study demonstrated that violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries.
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Affiliation(s)
- Grace F Gomez
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, 1121 West Michigan Street, Indianapolis, IN, 46202, USA.
| | - Ruijie Huang
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, 1121 West Michigan Street, Indianapolis, IN, 46202, USA
- Department of Pediatric Dentistry, West China School of Stomatology, Sichuan University, No. 14, 3rd Section of South Renmin Rd, Chengdu, Sichuan, 610041, China
| | - Meoghan MacPherson
- Department of Bioengineering, College of Engineering, Temple University, 1947 North 12th Street, Philadelphia, PA, 19122, USA
| | - Andrea G Ferreira Zandona
- Department of Operative Dentistry, The University of North Carolina at Chapel Hill - School of Dentistry, 436 Brauer Hall, Room 447, Chapel Hill, NC, 27599-7450, USA
| | - Richard L Gregory
- Department of Biomedical and Applied Sciences, Indiana University School of Dentistry, 1121 West Michigan Street, Indianapolis, IN, 46202, USA
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Zhang Y, Zhu Y, Chen J, Wang Y, Sherwood ME, Murray CK, Vrahas MS, Hooper DC, Hamblin MR, Dai T. Antimicrobial blue light inactivation of Candida albicans: In vitro and in vivo studies. Virulence 2016; 7:536-45. [PMID: 26909654 DOI: 10.1080/21505594.2016.1155015] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
Fungal infections are a common cause of morbidity, mortality and cost in critical care populations. The increasing emergence of antimicrobial resistance necessitates the development of new therapeutic approaches for fungal infections. In the present study, we investigated the effectiveness of an innovative approach, antimicrobial blue light (aBL), for inactivation of Candida albicans in vitro and in infected mouse burns. A bioluminescent strain of C. albicans was used. The susceptibilities to aBL (415 nm) were compared between C. albicans and human keratinocytes. The potential development of aBL resistance by C. albicans was investigated via 10 serial passages of C. albicans on aBL exposure. For the animal study, a mouse model of thermal burn infected with the bioluminescent C. albicans strain was used. aBL was delivered to mouse burns approximately 12 h after fungal inoculation. Bioluminescence imaging was performed to monitor in real time the extent of infection in mice. The results obtained from the studies demonstrated that C. albicans was approximately 42-fold more susceptible to aBL than human keratinocytes. Serial passaging of C. albicans on aBL exposure implied a tendency of reduced aBL susceptibility of C. albicans with increasing numbers of passages; however, no statistically significant difference was observed in the post-aBL survival rate of C. albicans between the first and the last passage (P>0.05). A single exposure of 432 J/cm(2) aBL reduced the fungal burden in infected mouse burns by 1.75-log10 (P=0.015). Taken together, our findings suggest aBL is a potential therapeutic for C. albicans infections.
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Affiliation(s)
- Yunsong Zhang
- a Department of Plastic Surgery and Cosmetic , The Second People's Hospital of Guangdong Province , Guangzhou , China.,b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA
| | - Yingbo Zhu
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,d School of Medicine, Tongji University , Shanghai , China
| | - Jia Chen
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,e Shanghai Dermatology Hospital , Shanghai , China
| | - Yucheng Wang
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,f Department of Laser Medicine , Chinese PLA General Hospital , Beijing , China
| | - Margaret E Sherwood
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA
| | - Clinton K Murray
- g Infectious Disease Service, Brooke Army Medical Center, Fort Sam Houston , TX , USA
| | - Mark S Vrahas
- h Department of orthopedic Surgery , Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA
| | - David C Hooper
- i Division of Infectious Diseases, Massachusetts General Hospital, Harvard Medical School , Boston , MA , USA
| | - Michael R Hamblin
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA.,j Harvard-MIT Division of Health Sciences and Technology , Cambridge , MA , USA
| | - Tianhong Dai
- b Wellman Center for Photomedicine, Massachusetts General Hospital , Boston , MA , USA.,c Department of Dermatology , Harvard Medical School , Boston , MA , USA
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25
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Cohen-Berneron J, Steinberg D, Featherstone JDB, Feuerstein O. Sustained effects of blue light on Streptococcus mutans in regrown biofilm. Lasers Med Sci 2016; 31:445-52. [PMID: 26796707 DOI: 10.1007/s10103-016-1873-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 01/11/2016] [Indexed: 12/22/2022]
Abstract
In prior studies, exposure of Streptococcus mutans in biofilm to blue light using high fluences of up to 680 J/cm(2) did not interfere with bacterial capability to reform an initial biofilm; however, a delayed antibacterial effect was observed. Our aim was to determine the sustained effecttts of blue light-emitting diode (LED) curing light on the pathogenicity of the newly formed biofilm. S. mutans were grown to form biofilm that was exposed to blue light (wavelengths, 460-480 nm) for 1, 3, and 7 min (equivalent to 37, 112, and 262 J/cm(2), respectively). Then, bacteria were suspended and allowed to regrow into new biofilms. The regrown biofilms were assessed for bacterial quantification by optical density (OD) measurement and quantitative polymerase chain reaction (qPCR), bacterial viability and extracellular polysaccharide production by fluorescent staining using confocal scanning laser microscopy, acid production by bacteria (acidogenicity), and bacterial survival at low pH (aciduricity) using qPCR. Bacterial growth in the regrown biofilms was increased when samples were previously exposed to light; however, under the confocal microscopy, a higher proportion of dead bacteria and a reduction in polysaccharide production were observed. The acidogenicity from the regrown biofilm was lowered as fluences of light increased. The aciduricity of the regrown biofilm was decreased, meaning less growth of bacteria into biofilm in low pH with increasing fluences. Blue light has sustained effects on S. mutans bacteria grown into new biofilm. Although bacterial growth in biofilm increased, bacterial viability and virulence characteristics were impaired. The cariogenic potential over time of S. mutans previously exposed to blue light when grown on tooth surfaces is yet to be determined.
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Affiliation(s)
- Julie Cohen-Berneron
- Biofilm Research Laboratory, Institute of Dental Sciences, Faculty of Dental Medicine, Hebrew University-Hadassah, Jerusalem, Israel.,Department of Prosthodontics, Faculty of Dental Medicine, Hebrew University-Hadassah, Jerusalem, Israel
| | - Doron Steinberg
- Biofilm Research Laboratory, Institute of Dental Sciences, Faculty of Dental Medicine, Hebrew University-Hadassah, Jerusalem, Israel
| | | | - Osnat Feuerstein
- Department of Prosthodontics, Faculty of Dental Medicine, Hebrew University-Hadassah, Jerusalem, Israel.
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26
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Lins de Sousa D, Araújo Lima R, Zanin IC, Klein MI, Janal MN, Duarte S. Effect of Twice-Daily Blue Light Treatment on Matrix-Rich Biofilm Development. PLoS One 2015; 10:e0131941. [PMID: 26230333 PMCID: PMC4521953 DOI: 10.1371/journal.pone.0131941] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 06/08/2015] [Indexed: 12/20/2022] Open
Abstract
Background The use of blue light has been proposed as a direct means of affecting local bacterial infections, however the use of blue light without a photosensitizer to prevent the biofilm development has not yet been explored. The aim of this study was to determine how the twice-daily treatment with blue light affects the development and composition of a matrix-rich biofilm. Methodology/Principal Findings Biofilms of Streptococcus mutans UA159 were formed on saliva-coated hydroxyapatite discs for 5 days. The biofilms were exposed twice-daily to non-coherent blue light (LumaCare; 420 nm) without a photosensitizer. The distance between the light and the sample was 1.0 cm; energy density of 72 J cm-2; and exposure time of 12 min 56 s. Positive and negative controls were twice-daily 0.12% chlorhexidine (CHX) and 0.89% NaCl, respectively. Biofilms were analyzed for bacterial viability, dry-weight, and extra (EPS-insoluble and soluble) and intracellular (IPS) polysaccharides. Variable pressure scanning electron microscopy and confocal scanning laser microscopy were used to check biofilm morphology and bacterial viability, respectively. When biofilms were exposed to twice-daily blue light, EPS-insoluble was reduced significantly more than in either control group (CHX and 0.89% NaCl). Bacterial viability and dry weight were also reduced relative to the negative control (0.89% NaCl) when the biofilms were treated with twice-daily blue light. Different morphology was also visible when the biofilms were treated with blue light. Conclusions Twice-daily treatment with blue light without a photosensitizer is a promising mechanism for the inhibition of matrix-rich biofilm development.
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Affiliation(s)
- Denise Lins de Sousa
- Department of Dental Clinics, School of Pharmacy, Dentistry and Nursing, Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Ramille Araújo Lima
- Department of Dental Clinics, School of Pharmacy, Dentistry and Nursing, Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Iriana Carla Zanin
- Department of Dental Clinics, School of Pharmacy, Dentistry and Nursing, Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Marlise I. Klein
- Department of Biomaterials, State University of São Paulo, Araraquara, São Paulo, Brazil
| | - Malvin N. Janal
- Department of Epidemiology and Health Promotion, College of Dentistry, New York University, NYU, New York, United States of America
| | - Simone Duarte
- Department of Basic Science and Craniofacial Biology, College of Dentistry, New York University, New York, United States of America
- * E-mail:
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27
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Percival SL, Francolini I, Donelli G. Low-level laser therapy as an antimicrobial and antibiofilm technology and its relevance to wound healing. Future Microbiol 2015; 10:255-72. [DOI: 10.2217/fmb.14.109] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
ABSTRACT The biostimulative effect of low-level laser therapy (LLLT) in tissues has been noted in reference to the treatment of various diseases but little information exists on its effectiveness on chronic wounds and biofilm. The scope of this review was to identify literature reporting on LLLT alone, without photodynamic agents, as an antimicrobial/antibiofilm technology and determine its effects on wound healing. Overall the beneficial effects of LLLT in promoting wound healing in animal and human studies has been demonstrated. However, the lack of credible studies using reproducible models and light dosimetry restricts the analysis of current data. Efforts must be addressed to standardize phototherapy procedures as well as to develop suitable in vitro and in vivo biofilm models to test LLLT efficacy in promoting biofilm eradication and wound healing.
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Affiliation(s)
- Steven L Percival
- Surface Science Research Centre, University of Liverpool, Liverpool, UK
- Institute of Ageing & Chronic Disease, University of Liverpool, Liverpool, UK
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