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de Oliveira RR, Schwartz-Filho HO, Novaes AB, Taba M. Antimicrobial Photodynamic Therapy in the Non-Surgical Treatment of Aggressive Periodontitis: A Preliminary Randomized Controlled Clinical Study. J Periodontol 2007; 78:965-73. [PMID: 17539707 DOI: 10.1902/jop.2007.060494] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The treatment of aggressive periodontitis has always presented a challenge for clinicians, but there are no established protocols and guidelines for the efficient control of the disease. METHODS Ten patients with a clinical diagnosis of aggressive periodontitis were treated in a split-mouth design study to either photodynamic therapy (PDT) using a laser source with a wavelength of 690 nm associated with a phenothiazine photosensitizer or scaling and root planing (SRP) with hand instruments. Clinical assessment of plaque index (PI), gingival index (GI), bleeding on probing (BOP), probing depth (PD), gingival recession (GR), and relative clinical attachment level (RCAL) were made at baseline and 3 months after treatment with an automated periodontal probe. RESULTS Initially, the PI was 1.0 +/- 0.5 in both groups. At the 3-month evaluation, the plaque scores were reduced and remained low throughout the study. A significant reduction of GI and BOP occurred in both groups after 3 months (P <0.05). The mean PD decreased in the PDT group from 4.92 +/- 1.61 mm at baseline to 3.49 +/- 0.98 mm after 3 months (P <0.05) and in SRP group from 4.92 +/- 1.14 mm at baseline to 3.98 +/- 1.76 mm after 3 months (P <0.05). The mean RCAL decreased in the PDT group from 9.93 +/- 2.10 mm at baseline to 8.74 +/- 2.12 mm after 3 months (P <0.05), and in the SRP group, from 10.53 +/- 2.30 mm at baseline to 9.01 +/- 3.05 mm after 3 months. CONCLUSION PDT and SRP showed similar clinical results in the non-surgical treatment of aggressive periodontitis.
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Affiliation(s)
- Rafael R de Oliveira
- Department of Bucco-Maxillo-Facial Surgery and Traumatology and Periodontology, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil
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102
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Qin Y, Luan X, Bi L, He G, Bai X, Zhou C, Zhang Z. Toluidine blue-mediated photoinactivation of periodontal pathogens from supragingival plaques. Lasers Med Sci 2007; 23:49-54. [PMID: 17361390 DOI: 10.1007/s10103-007-0454-x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2006] [Accepted: 02/15/2007] [Indexed: 10/23/2022]
Abstract
This study aimed to assess the effect of toluidine blue (TB)-mediated photodynamic inactivation of periodontal pathogens (PP) from periodontopathic patients. Photodynamic therapy (PDT) was carried out using TB and 635 nm laser light irradiation. The bactericidal effect was evaluated, and important PDT parameters including light intensity, energy dose, and TB concentration were determined. Our findings suggest that TB-mediated lethal photosensitization of PP in vivo is possible. However, to obtain ideal bactericidal effect, higher doses of light and photosensitizer should be required in treatment in vivo than their planktonic counterparts. The best therapeutic effect was observed in treatment by 1 mg/ml TB combined with 12 J/cm(2) at 159 mW/cm(2) light irradiation. Moreover, because of the considerable interindividual differences of bacterial populations, TB-mediated PDT might not be equally effective among periodontopathic patients, and further studies on improvement of this therapeutic modality is needed.
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Affiliation(s)
- Yanli Qin
- Department of Physics, Harbin Institute of Technology, P.O. Box 3025, 2 Yikuang Street, Nangang District, Science and Technology Park, Harbin, 150001, China
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103
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Usacheva MN, Teichert MC, Sievert CE, Biel MA. Effect of Ca+ on the photobactericidal efficacy of methylene blue and toluidine blue against gram-negative bacteria and the dye affinity for lipopolysaccharides. Lasers Surg Med 2007; 38:946-54. [PMID: 17163474 DOI: 10.1002/lsm.20400] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND AND OBJECTIVES Methylene blue (MB) and toluidine blue (TB) form metachromatic complexes with lipopolysaccharides (LPS). The greater photobactericidal efficacy of TB may be explained by its affinity for LPS. This study aims to elucidate the difference in photobactericidal efficacies between the dyes using Ca(2+) as a competitor for dye-binding sites on the bacterial outer membrane. STUDY DESIGN/MATERIALS AND METHODS Fixed dye concentration solutions with gram-negative bacteria and increasing concentrations of CaCl(2) were exposed to red laser light. Bacterial survival and spectrophotometry were used to describe the effect of Ca(2+) on dye interaction with bacteria and LPS. RESULTS MB-mediated photokilling was inhibited more significantly than that of TB. CaCl(2) inhibited dye photobleaching and suppressed the metachromatic reaction between the dyes and LPS, in particular TB. CONCLUSIONS CaCl(2) inhibits bacterial photokilling by binding with LPS, as well as other anionic polymers including outer membrane proteins. LPS is chiefly involved in TB-mediated photokilling, whereas outer membrane proteins probably are more involved in MB-mediated photokilling.
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Affiliation(s)
- Marina N Usacheva
- Advanced Photodynamic Technologies, Inc., Minneapolis, Minnesota 55414, USA
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104
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de Almeida JM, Theodoro LH, Bosco AF, Nagata MJH, Oshiiwa M, Garcia VG. Influence of Photodynamic Therapy on the Development of Ligature-Induced Periodontitis in Rats. J Periodontol 2007; 78:566-75. [PMID: 17335382 DOI: 10.1902/jop.2007.060214] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
BACKGROUND The purpose of this study was to evaluate, histologically and radiographically, the effect of photodynamic therapy on the progression of experimentally induced periodontal disease in rats. METHODS Ligatures were placed at the first mandibular molar in rats. The animals were divided into four groups: group 1 (C) received no treatment; group 2 was treated topically with methylene blue (MB; 100 microg/ml); group 3 was treated with low-level laser therapy (LLLT); and group 4 was treated topically with methylene blue followed by LLLT (4.5 J/cm(2)) (photodynamic therapy; PDT). Rats were sacrificed 5, 15, or 30 days postoperatively. Standardized radiographs were taken to measure bone loss around the mesial root surface of the first molar. Data were analyzed statistically (analysis of variance and Tukey test; P <0.05). A scoring system was used to evaluate the connective tissue, periodontal ligament, and alveolar bone histologically. Data were analyzed statistically (Kruskal-Wallis test; P <0.05). RESULTS Radiographic examination showed that there was significantly less bone loss in Group PDT compared to Group C at 5 and 15 days postoperatively. There was no significant difference in bone loss at 30 days. At 15 days, the histologic results showed significant differences in the extent of inflammatory reaction in the gingival tissue, with a greater extent of chronic inflammatory reaction in Group LLLT. CONCLUSION PDT transiently reduced the periodontal tissue destruction.
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Affiliation(s)
- Juliano Milanezi de Almeida
- Department of Surgery and Integrated Clinic, Division of Periodontics, São Paulo State University Júlio de Mesquita Filho, São Paulo State University, Araçatuba, SP, Brazil
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105
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Donnelly RF, McCarron PA, Tunney MM, David Woolfson A. Potential of photodynamic therapy in treatment of fungal infections of the mouth. Design and characterisation of a mucoadhesive patch containing toluidine blue O. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2007; 86:59-69. [PMID: 16963273 DOI: 10.1016/j.jphotobiol.2006.07.011] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2006] [Revised: 07/29/2006] [Accepted: 07/29/2006] [Indexed: 12/31/2022]
Abstract
Mucocutaneous oropharyngeal candidiasis is predominately caused by Candida albicans. The overall incidence of oral candidiasis in young adults has increased dramatically with the spread of HIV/AIDS. Conventional treatments have been shown to have a fungistatic rather than a fungicidal effect, resulting in an inadequate treatment outcome for patients. In addition, increasing resistance of C. albicans to antifungal agents has made effective treatment more difficult. Accordingly, interest has arisen in development of new prophylaxis/treatment regimens. One such alternative treatment is photodynamic antimicrobial chemotherapy (PACT), in which a combination of a photosensitising drug and visible light cause selective destruction of microbial cells. Due to the highly coloured nature of photosensitisers and the potential for staining of teeth, lips and buccal mucosa, administration of photosensitisers to humans as a liquid mouthwash is undesirable. Targeted delivery of the photosensitiser directly to the site of infection should be the aim. The current study, therefore, reports on a mucoadhesive patch containing toluidine blue O (TBO), as a potential delivery system for use in PACT of oropharyngeal candidiasis. Patches prepared from aqueous blends of poly(methyl vinyl ether/maleic anhydride) and tripropyleneglycol methyl ether possessed suitable properties for use as mucoadhesive drug delivery systems and were capable of resisting dissolution when immersed in artificial saliva. When releasing directly into an aqueous sink, patches containing 50 and 100mg TBO cm(-2) both generated receiver compartment concentrations exceeding the concentration (2.0-5.0 mg ml(-1)) required to produce high levels of kill (>90%) of both planktonic and biofilm-grown C. albicans upon illumination. However, the concentrations of TBO in the receiver compartments separated from patches by membranes intended to mimic biofilm structures were an order of magnitude below those inducing high levels of kill, even after 6h release. Therefore, short application times of TBO-containing mucoadhesive patches should allow treatment of recently-acquired oropharyngeal candidiasis, caused solely by planktonic cells. Longer patch application times may be required for persistent disease where biofilms are implicated.
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Affiliation(s)
- Ryan F Donnelly
- School of Pharmacy, Queen's University Belfast, Medical Biology Centre, 97 Lisburn Road, Belfast BT9 7BL, UK.
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106
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Donnelly RF, McCarron PA, Cassidy CM, Elborn JS, Tunney MM. Delivery of photosensitisers and light through mucus: investigations into the potential use of photodynamic therapy for treatment of Pseudomonas aeruginosa cystic fibrosis pulmonary infection. J Control Release 2006; 117:217-26. [PMID: 17196290 DOI: 10.1016/j.jconrel.2006.11.010] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Revised: 10/30/2006] [Accepted: 11/07/2006] [Indexed: 11/18/2022]
Abstract
Respiratory disease is the main cause of morbidity and mortality in patients with cystic fibrosis (CF). In such patients chronic Pseudomonas aeruginosa infection is virtually impossible to eradicate using antibiotic therapy. Photodynamic antimicrobial chemotherapy (PACT) could be one potential alternative antimicrobial method. As photosensitisers could be delivered to the lungs of CF patients via inhalation, the current in vitro study investigated the potential use of PACT in the treatment of P. aeruginosa CF pulmonary infection. Delivery of red light (635 nm) and two photosensitisers (toluidine blue O (TBO) and meso-tetra (N-methyl-4-pyridyl) porphine tetra tosylate (TMP)) across artificial CF mucus was successfully achieved. Artificial CF mucus reduced the measured fluence of incident light in an almost exponential manner with increasing depth. The presence of dissolved photosensitisers also reduced light fluence. TMP diffused more efficiently across artificial CF mucus than TBO. However, receiver compartment concentrations of both drugs after 6 h were of the same order as those required to achieve high rates of kill (>99%) of P. aeruginosa isolates growing both planktonically and in biofilms. TMP required significantly higher concentrations (2.5 mg ml(-1)) than TBO to achieve high rates of kill (>99%) of P. aeruginosa isolates growing planktonically. Higher concentrations (5.0 mg ml(-1)) of both photosensitisers were required to achieve high rates of kill (>99%) of P. aeruginosa isolates growing in biofilms. When photosensitisers were prepared in artificial mucus, higher concentrations were required to achieve reasonably high kill rates (>80%) of P. aeruginosa (PAO1) growing both planktonically and in biofilm.
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Affiliation(s)
- Ryan F Donnelly
- School of Pharmacy, Queen's University Belfast, Medical Biology Centre, Belfast, UK.
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107
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Reszka KJ, Denning GM, Britigan BE. Photosensitized oxidation and inactivation of pyocyanin, a virulence factor of Pseudomonas aeruginosa. Photochem Photobiol 2006; 82:466-73. [PMID: 16613500 DOI: 10.1562/2005-07-29-ra-626] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pyocyanin (PyO-) (1-hydroxy-5-methylphenazine) is a cytotoxic compound secreted by Pseudomonas aeruginosa, an omnipresent bacterium and a human pathogen. We report that visible light illumination in the presence of rose bengal, or riboflavin, in aerated solutions (pH 7.0-7.2) induces irreversible loss of the pigment's characteristic absorption band at 690 nm, indicating its oxidation. This photobleaching was paralleled by generation of a multiline Electron Paramagnetic Resonance (EPR) spectrum attributed to a PyO(-)-derived radical. The reaction was dependent on the presence of air, sensitizers and light, was inhibited by sodium azide and was unaffected by ethanol. This suggests that PyO- was oxidized largely via singlet oxygen and that hydroxyl radicals were not involved. The photochemically modified pigment was less efficient in oxidizing NAD(P)H and generated less superoxide (by approximately 50%) than the intact PyO-, indicating its partial inactivation. 1-Methoxy-5-methylphenazine, a PyO- analog in which the -O- moiety was replaced by the methoxy group (-OMe), was resistant to oxidation, suggesting that oxidation of PyO- involves its phenolate moiety. These results also suggest that photosensitization could be a potentially useful method for inactivation of PyO- and, possibly, detoxification of superficial wounds (skin, eye) infected with P. aeruginosa.
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108
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The potential for photodynamic therapy in the treatment of localized infections. Photodiagnosis Photodyn Ther 2005; 2:247-62. [DOI: 10.1016/s1572-1000(05)00099-2] [Citation(s) in RCA: 123] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2005] [Revised: 09/20/2005] [Accepted: 09/21/2005] [Indexed: 11/22/2022]
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109
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Wong TW, Wang YY, Sheu HM, Chuang YC. Bactericidal effects of toluidine blue-mediated photodynamic action on Vibrio vulnificus. Antimicrob Agents Chemother 2005; 49:895-902. [PMID: 15728881 PMCID: PMC549273 DOI: 10.1128/aac.49.3.895-902.2005] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Vibrio vulnificus is a gram-negative, highly invasive bacterium responsible for human opportunistic infections. We studied the antibacterial effects of toluidine blue O (TBO)-mediated photodynamic therapy (PDT) for V. vulnificus wound infections in mice. Fifty-three percent (10 of 19) of mice treated with 100 microg of TBO per ml and exposed to broad-spectrum red light (150 J/cm(2) at 80 mW/cm(2)) survived, even though systemic septicemia had been established with a bacterial inoculum 100 times the 50% lethal dose. In vitro, the bacteria were killed after exposure to a lower light dose (100 J/cm(2) at 80 mW/cm(2)) in the presence of low-dose TBO (0.1 microg/ml). PDT severely damaged the cell wall and reduced cell motility and virulence. Cell-killing effects were dependent on the TBO concentration and light doses and were mediated partly through the reactive oxygen species generated during the photodynamic reaction. Our study has demonstrated that PDT can cure mice with otherwise fatal V. vulnificus wound infections. These promising results suggest the potential of this regimen as a possible alternative to antibiotics in future clinical applications.
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Affiliation(s)
- Tak-Wah Wong
- Department of Dermatology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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110
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Meisel P, Kocher T. Photodynamic therapy for periodontal diseases: State of the art. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2005; 79:159-70. [PMID: 15878121 DOI: 10.1016/j.jphotobiol.2004.11.023] [Citation(s) in RCA: 245] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2003] [Revised: 05/19/2004] [Accepted: 11/01/2004] [Indexed: 11/17/2022]
Abstract
BACKGROUND Photodynamic killing of periodontopathogenic bacteria may be an alternative to the systemic application of antibacterial drugs used in the treatment of periodontal diseases. Even though the method is still in the experimental stage, increasing bacterial resistance problems may promote the introduction of photodynamic therapy (PDT) into periodontal practice. AIM In this review a literature survey is given of PDT as seen from a periodontal perspective. METHODS In this review, the present knowledge and experience of PDT is summarized. Literature data are presented on drawbacks of conventional antibiotics, the mechanism of PDT, bactericidal effects of PDT as well as results of clinical efforts. The future prospects of the method are discussed. RESULTS The application of photosensitizing dyes and their excitation by visible light enables effective killing of periodontopathogens. Encouraging studies using PDT in periodontitis and in peri-implantitis are known. CONCLUSION Even though PDT is still in experimental stages of development and testing, the method may be an adjunct to conventional antibacterial measures in periodontology. Clinical follow-up studies are needed to confirm the efficacy of the procedure.
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Affiliation(s)
- Peter Meisel
- Department of Pharmacology, Ernst Moritz Arndt University Greifswald, F-Loeffler-Str. 23d, D-17487 Greifswald, Germany.
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111
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Sharma M, Bansal H, Gupta PK. Virulence of Pseudomonas aeruginosa Cells Surviving Photodynamic Treatment with Toluidine Blue. Curr Microbiol 2005; 50:277-80. [PMID: 15886909 DOI: 10.1007/s00284-005-4473-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2004] [Accepted: 01/02/2005] [Indexed: 10/25/2022]
Abstract
We report results of a study carried out to investigate photodynamic effect of Touildine blue (TBO) on virulent factors secreted by Pseudomonas aeruginosa. Viability of MCF-7 cells incubated with culture supernatants of bacteria photosensitized with TBO (experimental) was found to be higher than that for MCF-7 cells incubated with culture supernatants of bacterial cells treated either with TBO in dark (control II) or not receiving any treatment (neither TBO nor light (control I)). Furthermore, whereas MCF-7 cells incubated with supernatants of bacteria, control I and II, showed significant morphological alterations, no such changes were observed in MCF-7 cells incubated with supernatant of experimental cells. The activities of phospholipase C and proteases, virulent factors of P. aeruginosa, were also found to decrease on photosensitization. These results suggest that the potency of virulent factors is reduced in cells surviving photodynamic treatment with TBO and this may have implication in treatment of infections caused by P. aeruginosa.
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Affiliation(s)
- Mrinalini Sharma
- Biomedical Applications Section, Centre for Advanced Technology, Indore-452013, India.
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112
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Usacheva MN, Teichert MC, Biel MA. The interaction of lipopolysaccharides with phenothiazine dyes. Lasers Surg Med 2004; 33:311-9. [PMID: 14677158 DOI: 10.1002/lsm.10226] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
BACKGROUND AND OBJECTIVES The difference in the photobactericidal efficacy of methylene blue and toluidine blue against gram-negative bacteria may result from their primary reaction with lipopolysaccharides (LPS) of the outer bacterial membrane. The aim of the present study was to compare the reactivity of these dyes with LPS extracted from different gram-negative bacteria. STUDY DESIGN/MATERIALS AND METHODS The interactions of methylene blue and toluidine blue with LPS from Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella pneumoniae (K. pneumoniae), and Serratia marcescens (S. marcescens) were studied spectrophotometrically in 0.45% saline. The dyes were used at the concentration of 10 microM. The concentrations of LPS ranged from 5-100 microg/ml. RESULTS Methylene blue and toluidine blue enter into a metachromatic reaction with the LPS resulting the in generation of dimers of methylene blue and higher aggregates of toluidine blue. The more significant hypochromic and hypsochromic effects in the reaction of the latter with LPS indicate a greater metachromatic efficacy of toluidine blue than methylene blue. The equilibrium constants of the metachromatic complex between toluidine blue and different LPS were calculated. The spectrophotometric titration of LPS with the dyes was used to estimate the equivalent weight of LPS. CONCLUSIONS Toluidine blue interacts with LPS more significantly than methylene blue in vitro. This may be one of the main factors determining its greater photobactericidal efficacy against gram-negative bacteria.
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Affiliation(s)
- Marina N Usacheva
- Advanced Photodynamic Technologies, Inc., Minneapolis, Minnesota 55414, USA
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113
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Hamblin MR, Hasan T. Photodynamic therapy: a new antimicrobial approach to infectious disease? Photochem Photobiol Sci 2004; 3:436-50. [PMID: 15122361 PMCID: PMC3071049 DOI: 10.1039/b311900a] [Citation(s) in RCA: 1334] [Impact Index Per Article: 66.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Photodynamic therapy (PDT) employs a non-toxic dye, termed a photosensitizer (PS), and low intensity visible light which, in the presence of oxygen, combine to produce cytotoxic species. PDT has the advantage of dual selectivity, in that the PS can be targeted to its destination cell or tissue and, in addition, the illumination can be spatially directed to the lesion. PDT has previously been used to kill pathogenic microorganisms in vitro, but its use to treat infections in animal models or patients has not, as yet, been much developed. It is known that Gram-(-) bacteria are resistant to PDT with many commonly used PS that will readily lead to phototoxicity in Gram-(+) species, and that PS bearing a cationic charge or the use of agents that increase the permeability of the outer membrane will increase the efficacy of killing Gram-(-) organisms. All the available evidence suggests that multi-antibiotic resistant strains are as easily killed by PDT as naive strains, and that bacteria will not readily develop resistance to PDT. Treatment of localized infections with PDT requires selectivity of the PS for microbes over host cells, delivery of the PS into the infected area and the ability to effectively illuminate the lesion. Recently, there have been reports of PDT used to treat infections in selected animal models and some clinical trials: mainly for viral lesions, but also for acne, gastric infection by Helicobacter pylori and brain abcesses. Possible future clinical applications include infections in wounds and burns, rapidly spreading and intractable soft-tissue infections and abscesses, infections in body cavities such as the mouth, ear, nasal sinus, bladder and stomach, and surface infections of the cornea and skin.
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Affiliation(s)
- Michael R Hamblin
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA.
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114
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Gad F, Zahra T, Francis KP, Hasan T, Hamblin MR. Targeted photodynamic therapy of established soft-tissue infections in mice. Photochem Photobiol Sci 2004; 3:451-8. [PMID: 15122362 PMCID: PMC3071693 DOI: 10.1039/b311901g] [Citation(s) in RCA: 121] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The worldwide rise in antibiotic resistance necessitates the development of novel antimicrobial strategies. Although many workers have used photodynamic therapy (PDT) to kill bacteria in vitro, the use of this approach has seldom been reported in vivo in animal models of infection. We have previously described the first use of PDT to treat excisional wound infections by Gram-(-) bacteria in living mice. However, these infected wound models involved a short timespan between infection (30 min) and treatment by PDT. We now report on the use of PDT to treat an established soft-tissue infection in mice. We used Staphylococcus aureus stably transformed with a Photorhabdus luminescenslux operon (luxABCDE) that was genetically modified to be functional in Gram-(+) bacteria. These engineered bacteria emitted bioluminescence, allowing the progress of the infection to be monitored in both space and time with a low light imaging charge-coupled device (CCD) camera. One million cells were injected into one or both thigh muscles of mice that had previously been rendered neutropenic by cyclophosphamide administration. Twenty-four hours later, the bacteria had multiplied more than one hundredfold; poly-L-lysine chlorin e6 conjugate or free chlorin e6 was injected into one area of infected muscle and imaged with the CCD camera. Thirty minutes later, red light from a diode laser was delivered as a surface spot or by interstitial fiber into the infection. There was a light dose dependent loss of bioluminescence (to <5% of that seen in control infections) not seen in untreated infections or those treated with light alone, but in some cases, the infection recurred. Treatment with conjugate alone led to a lesser reduction in bioluminescence. Infections treated with free chlorin e6 responded less well and the infection subsequently increased over the succeeding days, probably due to PDT-mediated tissue damage. PDT-treated infected legs healed better than legs with untreated infections. This data shows that PDT may have applications in drug-resistant soft-tissue infections.
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Affiliation(s)
- Faten Gad
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
| | - Touqir Zahra
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
- Newton Wellesley Hospital, 2014 Washington Street, Newton, MA 02462, USA
| | - Kevin P. Francis
- Xenogen Corporation, 860 Atlantic Avenue, Alameda, CA 94501, USA
| | - Tayyaba Hasan
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
| | - Michael R. Hamblin
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, Boston, MA 02114, USA
- Department of Dermatology, Harvard Medical School, Boston, MA 02115, USA
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115
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Phoenix DA, Sayed Z, Hussain S, Harris F, Wainwright M. The phototoxicity of phenothiazinium derivatives against Escherichia coli and Staphylococcus aureus. ACTA ACUST UNITED AC 2004; 39:17-22. [PMID: 14556991 DOI: 10.1016/s0928-8244(03)00173-1] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Phenothiazinium dyes, and derivatives, were tested for toxicity to Escherichia coli and Staphylococcus aureus. The dyes were generally lipophilic (log P>1) and showed inherent dark toxicity (minimum lethal concentrations: 3.1-1000 microM). Dye illumination (total light dose of 3.15 J cm(-1) over 30 min) led to up to eight-fold reductions in minimum lethal concentrations. Most of the illuminated dyes showed significant relative singlet oxygen yields (phi'delta: 0.18-1.35) suggesting a type II mechanism of generating a phototoxic response. Although generally up to six-fold more effective against S. aureus, the dyes tested efficiently killed E. coli and may be of particular use in combating Gram-negative pathogens.
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Affiliation(s)
- D A Phoenix
- Department of Forensic and Investigative Science, University of Central Lancashire, Preston PR1 2HE, UK.
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116
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Matevski D, Weersink R, Tenenbaum HC, Wilson B, Ellen RP, Lépine G. Lethal photosensitization of periodontal pathogens by a red-filtered Xenon lamp in vitro. J Periodontal Res 2003; 38:428-35. [PMID: 12828662 DOI: 10.1034/j.1600-0765.2003.00673.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND The ability of Helium-Neon (He-Ne) laser irradiation of a photosensitizer to induce localized phototoxic effects that kill periodontal pathogens is well documented and is termed photodynamic therapy (PDT). OBJECTIVES We investigated the potential of a conventional light source (red-filtered Xenon lamp) to activate toluidine blue O (TBO) in vitro and determined in vitro model parameters that may be used in future in vivo trials. MATERIALS AND METHODS Porphyromonas gingivalis 381 was used as the primary test bacterium. RESULTS Treatment with a 2.2 J/cm2 light dose and 50 micro g/ml TBO concentration resulted in a bacterial kill of 2.43 +/- 0.39 logs with the He-Ne laser control and 3.34 +/- 0.24 logs with the lamp, a near 10-fold increase (p = 0.028). Increases in light intensity produced significantly higher killing (p = 0.012) that plateaued at 25 mW/cm2. There was a linear relationship between light dose and bacterial killing (r2 = 0.916); as light dose was increased bacterial survival decreased. No such relationship was found for the drug concentrations tested. Addition of serum or blood at 50% v/v to the P. gingivalis suspension prior to irradiation diminished killing from approximately 5 logs to 3 logs at 10 J/cm2. When serum was washed off, killing returned to 5 logs for all species tested except Bacteroides forsythus (3.92 +/- 0.68 logs kill). CONCLUSIONS The data indicate that PDT utilizing a conventional light source is at least as effective as laser-induced treatment in vitro. Furthermore, PDT achieves significant bactericidal activity in the presence of serum and blood when used with the set parameters of 10 J/cm2, 100 mW/cm2 and 12.5 micro g/ml TBO.
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Affiliation(s)
- Donco Matevski
- Faculty of Dentistry, University of Toronto, University of Toronto, Ontario, Canada
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Affiliation(s)
- David A Phoenix
- Deans Office, Faculty of Science, University of Central Lancashire, Preston PR1 2HE, UK.
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118
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Hamblin MR, Zahra T, Contag CH, McManus AT, Hasan T. Optical monitoring and treatment of potentially lethal wound infections in vivo. J Infect Dis 2003; 187:1717-25. [PMID: 12751029 PMCID: PMC3441051 DOI: 10.1086/375244] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2002] [Accepted: 12/31/2002] [Indexed: 01/26/2023] Open
Abstract
We report on the use of optical techniques to monitor and treat Pseudomonas aeruginosa wound infections in mice. Bioluminescent bacteria transduced with a plasmid containing a bacterial lux gene operon allow the infection in excisional mouse wounds to be imaged by use of a sensitive charge-coupled device camera. Photodynamic therapy (PDT) targeted bacteria, by use of a polycationic photosensitizer conjugate, which is designed to penetrate the gram-negative cell wall and was topically applied to the wound and was followed by red-light illumination. There was a rapid light dose-dependent loss of luminescence, as measured by image analysis, in the wounds treated with conjugate and light, a loss that was not seen in untreated wounds, wounds treated with light alone, or wounds treated with conjugate alone. P. aeruginosa was invasive in our mouse model, and all 3 groups of control mice died within 5 days; in contrast, 90% of PDT-treated mice survived. PDT-treated wounds healed significantly faster than did silver nitrate-treated wounds, and this was not due to either inhibition of healing by silver nitrate or stimulation of healing by PDT.
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Affiliation(s)
- Michael R Hamblin
- Wellman Laboratories of Photomedicine, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School, Boston, Massachusetts 02114, USA.
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Kömerik N, Nakanishi H, MacRobert AJ, Henderson B, Speight P, Wilson M. In vivo killing of Porphyromonas gingivalis by toluidine blue-mediated photosensitization in an animal model. Antimicrob Agents Chemother 2003; 47:932-40. [PMID: 12604524 PMCID: PMC149320 DOI: 10.1128/aac.47.3.932-940.2003] [Citation(s) in RCA: 208] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Porphyromonas gingivalis is one of the major causative organisms of periodontitis and has been shown to be susceptible to toluidine blue-mediated photosensitization in vitro. The aims of the present study were to determine whether this technique could be used to kill the organism in the oral cavities of rats and whether this would result in a reduction in the alveolar bone loss characteristic of periodontitis. The maxillary molars of rats were inoculated with P. gingivalis and exposed to up to 48 J of 630-nm laser light in the presence of toluidine blue. The number of surviving bacteria was then determined, and the periodontal structures were examined for evidence of any damage. When toluidine blue was used together with laser light there was a significant reduction in the number of viable P. gingivalis organisms. No viable bacteria could be detected when 1 mg of toluidine blue per ml was used in conjunction with all light doses used. On histological examination, no adverse effect of photosensitization on the adjacent tissues was observed. In a further group of animals, after time was allowed for the disease to develop in controls, the rats were killed and the level of maxillary molar alveolar bone was assessed. The bone loss in the animals treated with light and toluidine blue was found to be significantly less than that in the control groups. The results of this study show that toluidine blue-mediated lethal photosensitization of P. gingivalis is possible in vivo and that this results in decreased bone loss. These findings suggest that photodynamic therapy may be useful as an alternative approach for the antimicrobial treatment of periodontitis.
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Affiliation(s)
- N Kömerik
- Department of Microbiology, Eastman Dental Institute for Oral Health Care Sciences, University College London, United Kingdom
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