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PURPOSE: This study aimed to investigate the efficiency of antimicrobial photodynamic therapy (aPDT) on Streptococcus mutans biofilm in the oral cavity using the photosensitizer chloroaluminum phthalocyanine encapsulated in chitosan nanoparticles (ClAlPc/Ch) at three preirradiation times. METHODS: Biofilms of Streptococcus mutans strains (ATCC 25,175) were cultivated on bovine tooth blocks and exposed to a 10% sucrose solution three times a day for 1 min over three consecutive days. The samples were randomly distributed into five treatment groups (n = 5): (I) aPDT with ClAlPc/Ch with a preirradiation time of 5 min (F5), (II) aPDT with ClAlPc/Ch with a preirradiation time of 15 min (F15), (III) aPDT with ClAlPc/Ch with a preirradiation time of 30 min (F30), (IV) 0.12% chlorhexidine digluconate (CHX), and (V) 0.9% saline solution (NaCl). After treatment, the S. mutans biofilms formed on each specimen were collected to determine the number of viable bacteria (colony-forming units (CFU)/mL). Data were analyzed for normality using the Shapiro-Wilk test and the analysis of variance (ANOVA) and Tukey HSD tests to analyze the number of viable bacteria (α = 0.05). RESULTS: The one-way ANOVA showed a difference between the groups (p = 0.0003), and the Tukey HSD posttest showed that CHX had the highest microbial reduction of S. mutans, not statistically different from the F5 and F15 groups, whereas the NaCl group had the lowest microbial reduction statistically similar to the F30 group. CONCLUSION: The results demonstrate that aPDT mediated by ClAlPc/Ch when used at preirradiation times of 5-15 min can be an effective approach in controlling cariogenic biofilm of S. mutans, being an alternative to 0.12% CHX.
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Biofilmes , Quitosana , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Streptococcus mutans , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/efeitos da radiação , Streptococcus mutans/fisiologia , Fotoquimioterapia/métodos , Quitosana/farmacologia , Quitosana/química , Nanopartículas/química , Biofilmes/efeitos dos fármacos , Biofilmes/efeitos da radiação , Animais , Bovinos , Fármacos Fotossensibilizantes/farmacologia , Técnicas In Vitro , Indóis/farmacologia , Boca/microbiologia , Clorexidina/farmacologia , Clorexidina/análogos & derivados , Viabilidade Microbiana/efeitos dos fármacos , Viabilidade Microbiana/efeitos da radiação , Compostos OrganometálicosRESUMO
Introduction: The success of endodontic treatment is based on microbial reduction promoted by the interaction of chemical and mechanical procedures. Photodynamic therapy (PDT) is used as an adjunct to conventional treatment, with significant microbial reduction. This study aimed to evaluate the influence of passive ultrasonic irrigation (PUI) of the photosensitizer (PS) used in PDT on microbial reduction in the root canal system. Materials and Methods: Forty-five mesiobuccal root canals from extracted human mandibular molars that were inoculated with standard strains of Enterococcus faecalis, Candida albicans, and Streptococcus mutans for 21 days were selected. The root canals were prepared using the ProTaper Next system and randomly divided into 3 groups (n=15): 1) PDT: PDT alone; 2) PUI+PDT: PUI followed by PDT; and 3) PUI/PS+PDT: PUI of the PS followed by PDT. Microbiological samples were collected from the canals before and after using the protocols described above. The data were analyzed by analysis of variance (Tukey's test) at a significance level of 5%. Results: Microbial counts before PDT, PUI+PDT, and PUI/PS+PDT did not differ significantly (P>0.05), showing methodological standardization in the microbial contamination of the root canal system. There was a significant reduction in microbial counts after PDT (61.05%), PUI+PDT (65.04%), and PUI/PS+PDT (68.58%) (P<0.01), but with no statistically significant difference between the three groups (P>0.05). Conclusion: Based on the present findings, it was concluded that the combination of PUI with PDT or PS activation did not influence microbial reduction achieved by PDT alone.
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Antimicrobial photodynamic therapy (a-PDT) is a modality that aims to induce microorganisms through visible light, a photosensitizer, and molecular oxygen. This therapy has shown promising results in controlling cariogenic biofilm in vitro and in vivo counterparts. This study investigated bacterial viability and morphological characterization of Streptococcus mutans mature biofilms after combination of erythrosine and a high potency dental curing light. Biofilms were formed on saliva-coated hydroxyapatite disks in batch culture. The samples were performed in triplicates. Fresh medium was replaced daily for five days and treated using 40 µM of E activated by HL 288 J/cm2 and total dose of 226 J at 1200 mW/cm2. Phosphate buffer saline and 0.12% of chlorhexidine were used as negative and positive control, respectively. After treatment, biofilms were assessed for microbial viability and morphological characterization by means of bio-volume and thickness. COMSTAT software was used for image analysis. Data were analyzed using two-way ANOVA followed by Tukey test with significance level 5%. The application of a-PDT and CHX treatments decreased S. mutans bacterial viability. The image analysis showed more red cells on biofilms when compared to other groups, demonstrating photobacterial killing. Erythrosine irradiated with a high potency curing light can potentially act as an antimicrobial tool in the treatment of cariogenic biofilms. The morphology and viability of microorganisms were impacted after treatment. Treatment with photodynamic therapy may be able to reduce the bio-volume and viability of bacteria present in biofilms. CLINICAL RELEVANCE AND RESEARCH HIGHLIGHTS: The use of the a-PDT technique has been applied in dentistry with satisfactory results. Some applications of this technique are in stomatology and endodontics. In the present study, we sought to understand the use of photodynamic therapy in the control of biofilm and the results found are compatible with the objective of microbiological control proposed by this technique, thus raising the alert for future studies in vivo using the combination of a-PDT with erythrosine, since they are easily accessible materials for the dental surgeon and can be applied in clinical practice.
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Anti-Infecciosos , Streptococcus mutans , Eritrosina/farmacologia , Viabilidade Microbiana , Biofilmes , Microscopia ConfocalRESUMO
ABSTRACT Purpose: This study aimed to examine the effects of unilateral corneal collagen cross-linking treatment on visual acuity and the topographic findings of the fellow untreated eye of patients who had bilateral progressive keratoconus. Methods: Patients with progressive keratoconus who underwent cross-linking treatment were screened retrospectively. A total of 188 untreated eyes of 188 patients whose eyes were treated unilaterally with either standard or accelerated cross-linking and refused cross-linking procedure for the fellow eye were included. Visual acuity and topographic findings of the fellow untreated eyes were obtained preoperatively and postoperatively at the 1st, 3rd, 6th, 12th, 24th, 30th, and 36th months. Results: The change over time of variables examined was similar in the untreated eyes of patients who received standard and accelerated cross-linking methods (p>0.05). At the 12th month, 136 (95.8%) untreated eyes were stable according to progression criteria. Only 4 (8%) eyes were progressive at the 24th month. No progression was observed in any of the 16 patients with a 36-month follow up. Conclusions: The results showed that the fellow untreated eyes of patients with bilateral progressive keratoconus did not have significant progression rates after unilateral cross-linking treatment.
RESUMO Objetivo: Examinar os efeitos do tratamento de reticulação unilateral do colágeno corneano na acuidade visual e os achados topográficos em olhos não tratados de pacientes com ceratocone progressivo bilateral. Métodos: Foram rastreados retrospectivamente pacientes com ceratocone progressivo submetidos a tratamento de reticulação. Foram incluídos no estudo 188 olhos não tratados de 188 pacientes tratado unilateralmente com reticulação padrão ou acelerada e que recusaram o procedimento de reticulação no outro olho. A acuidade visual e os achados topográficos dos olhos não tratados foram obtidos no pré- e pós-operatório no 1º, 3º, 6º, 12º, 24º, 30º e 36º mês. Resultados: As alterações ao longo do tempo foram semelhantes para as variáveis examinadas nos olhos não tratados de pacientes tratados com métodos de reticulação padrão e acelerado (p>0,05). No 12º mês, 136 olhos não tratados (95,8%) estavam estáveis, de acordo com os critérios de progressão. Apenas quatro olhos (8%) mostraram progressão no 24º mês. Nenhuma progressão foi observada nos 16 pacientes que tiveram um acompanhamento de 36 meses. Conclusões: O estudo mostrou que os olhos não tratados de pacientes com ceratocone progressivo bilateral não apresentaram taxas de progressão significativas após o tratamento unilateral com reticulação.
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Diversos autores desenvolveram estudos acerca da potencial associação entre a etiocarcinogênese do carcinoma espinocelular não melanocítico (CECNM) labial e o uso crônico da hidroclorotiazida (HCTZ). Objetivo: A atual revisão objetivou investigar a relação do diurético HCTZ e o risco de CECNM labial. Métodos: Realizou-se uma revisão de literatura nas bases de dados LILACS, PUBMED/MEDLINE e Periódico CAPES, em que foram incluídos artigos em inglês, português e francês, publicados no período de 2017 a 2022. Foram propostos 60 documentos e, dentre esses, 30 foram selecionados para compor a amostra no estudo. Resultados: Foi evidenciada uma relação entre o uso da HCTZ e a ocorrência de CENM com relação dose cumulativa devido às alterações provocadas pelo fármaco, no entanto, em virtude da heterogeneidade de desenhos metodológicos e concentração dos estudos em populações semelhantes, existem limitações quanto à confiabilidade dessas informações. Conclusão: Identificou-se uma desproporção entre a ocorrência e relevância do CENM e a produção científica vigente, demonstrando a necessidade de estudos com metodologias padronizadas que abranjam diferentes especificidades socioeconômicas e demográficas.(AU)
Several authors have developed studies about a potential association between the etiocarcinogenesis of non-melanocytic lip squamous cell carcinoma (NMSCC) and the chronic use of hydrochlorothiazide (HCTZ). Objective: The current study aimed to investigate the relation between the diuretic HCTZ and the risk of lip NMSCC. Methods: A literature review was carried out in the LILACS, PUBMED/MEDLINE and CAPES Periodical databases, which included articles in English, Portuguese and French, published between 2017 and 2022. Sixty documents were collected and, among these, 30 were selected to compose the sample in the study. Results: There was evidence of a relationship between the use of HCTZ and the occurrence of MSCC with a cumulative dose relationship due to changes caused by the drug, however, because of the heterogeneity of methodological designs and concentration of studies in similar populations, there are limitations regarding the reliability of this information. Conclusion: A disproportion between the occurrence and relevance of the NMSCC and the current scientific production was identified, demonstrating the need for studies with standardized methodologies that cover different demographic socioeconomic specificities.(AU)
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Humanos , Neoplasias Labiais/induzido quimicamente , Carcinoma de Células Escamosas/induzido quimicamente , Diuréticos/efeitos adversos , Hidroclorotiazida/efeitos adversos , Transtornos de Fotossensibilidade/induzido quimicamente , Fatores de Risco , Carcinogênese/induzido quimicamenteRESUMO
BACKGROUND: This study summarized the available evidence about the use of photodynamic therapy (PDT) for the management of oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC). METHODS: An overview of systematic reviews was undertaken based on the 2020 PRISMA statement. Electronic searches were performed in five databases. Studies published up to November 2022 were included. Risk of bias was assessed with the AMSTAR 2 tool. RESULTS: A total of 30 studies enrolling 9,245 individuals with OPMD (n = 7,487) or OSCC (n = 1,758) met the selection criteria. All studies examined the efficacy and/or safety of PDT. OPMD were investigated individually in 82.8% of the studies, the most common being oral lichen planus and actinic cheilitis. OSCC was addressed separately in 10.3% of the studies, while only 6.9% evaluated both OPMD and OSCC. Fourteen different types of photosensitizers were described. PDT was used according to the following setting parameters: 417-670 nm, 10-500 mW/cm2, 1.5-200 J/cm2, and 0.5-143 min. Regarding OPMD, leukoerythroplakia showed the best response rates, while oral lichen planus presented a partial or no response in nearly 75% of documented cases. A complete response was observed in 85.9% of OSCC cases, while 14.1% had no resolution. CONCLUSION: Overall, the response to PDT depended on the type of OPMD/OSCC and the parameters used. Although PDT is an emerging candidate for the treatment of OPMD and OSCC, there is heterogeneity of the methodologies used and the clinical data obtained, particularly regarding the follow-up period.
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Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Líquen Plano Bucal , Doenças da Boca , Neoplasias Bucais , Fotoquimioterapia , Lesões Pré-Cancerosas , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Líquen Plano Bucal/tratamento farmacológico , Doenças da Boca/tratamento farmacológico , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/patologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Lesões Pré-Cancerosas/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Revisões Sistemáticas como AssuntoRESUMO
In our previous study, Chlorin-e6 (Ce6) demonstrated a significant reduction of microorganisms' viability against single-species biofilm related to periodontitis once irradiated by red light (660 nm). Also, higher bacteria elimination was observed under blue light (450 nm) irradiation. However, the use of blue light irradiation of Ce6 for antimicrobial administration is poorly explored. This study evaluated the effect of chlorin-e6-mediated antimicrobial photodynamic therapy (aPDT) using different wavelengths (450 or 660 nm) against multi-species biofilms related to periodontitis. Streptococcus oralis, Fusobacterium nucleatum, Porphyromonas gingivalis, and Aggregatibacter actinomycetemcomitans composed the mature biofilm developed under proper conditions for five days. aPDT was performed using different concentrations of Ce6 (100 and 200 µM), wavelengths (450 or 660 nm), and comparisons were made after qPCR assay and confocal laser scanning microscopy (CLSM) analysis. The greatest bacterial elimination was observed in the groups where Ce6 was used with blue light, for S. orallis (2.05 Log10 GeQ mL-1, p < 0.0001) and P. gingivalis (1.4 Log10 GeQ mL-1, p < 0.0001), aPDT with red light showed significant bacteria reduction only for S. orallis. aPDT with blue light demonstrated statistically higher elimination in comparison with aPDT with red light. The aPDT did not show a statistically significant effect when tested against A. actinomycetemcomitans and F. nucleatum (p=0.776 and 0.988, respectively). The aPDT using blue light showed a promising higher photobiological effect, encouraging researchers to consider it in the irradiation of Ce6 for further investigations.
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Anti-Infecciosos , Periodontite , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Fotoquimioterapia/métodos , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Anti-Infecciosos/uso terapêutico , Biofilmes , Porphyromonas gingivalisRESUMO
Sporotrichosis is a worldwide zoonosis, prevalent in tropical and subtropical regions. In recent years, there has been a substantial increase in human and feline cases reported in Brazil. Despite this, the antifungal treatment for sporotrichosis is still limited, and thus, research into new therapeutic modalities must be encouraged. Recently, photodynamic therapy has been introduced as a treatment for sporotrichosis. This work presents an overview of both in vitro and in vivo studies that have used photodynamic therapy in the context of photoinactivation of Sporothrix species. Until now, as far as the authors are aware, this is the first scope review specifically on photodynamic therapy for the treatment of sporotrichosis. A systematic electronic search was conducted in two databases: Web of Science and PubMed. Seven original articles published from 2010 to July 2021 were selected, six of which met the proposed inclusion and exclusion criteria and were considered in this scoping review. Concerning the photoinactivation of Sporothrix spp. the results have been promising as studies, in both animals and humans, have reported significant clinical and mycological effects. The most used photosensitizers were methylene blue and its derivatives, and aminolevulinic acid and its methyl derivative, methyl aminolevulinic acid. In conclusion, photodynamic therapy has great potential in treatment of sporotrichosis, as its fungicidal effect both in vitro and in vivo has clearly been demonstrated. Photodynamic therapy could be used in conjunction with classic antifungal agents to optimize treatment outcomes.
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Fotoquimioterapia , Sporothrix , Esporotricose , Animais , Antifúngicos/uso terapêutico , Brasil , Humanos , Fotoquimioterapia/métodos , Esporotricose/tratamento farmacológico , Esporotricose/microbiologia , Esporotricose/veterináriaRESUMO
Aim: To compare Enterococcus faecalis reduction after antimicrobial photodynamic therapy (aPDT) used with methylene blue, toluidine blue, tannin, and curcumin as photosensitizers, an adjunct to endodontic chemomechanical preparation (CMP) in root canals of human teeth. Methods: A total of 120 single-rooted teeth were divided into 6 groups (n = 20): G1- CMP and 2.5% sodium hypochlorite (NaOCl); G2- CMP and saline solution; G3- CMP, 2.5% NaOCl, and aPDT with 0.005% methylene blue; G4- CMP, 2.5% NaOCl, and aPDT with 0.005% toluidine blue; G5- CMP, 2.5% NaOCl, and aPDT with 0.005% tannin; and G6- CMP, 2.5% NaOCl, and aPDT with 0.005% curcumin. A portable semiconductor laser was used (660 nm, 100 mW, 1.8 J, 180s) in groups 1, 2, 3, 4, 5, and a blue LED light-curing (420-480 nm, 1200 mV/cm2 ) in G6. For all groups, a 5 min pre-irradiation time was applied. Samples were collected before (initial collection), immediately after (intermediate collection) and 7 days after CMP (final collection) for colony-forming unit (CFU) counting. The Kruskal-Wallis test and analysis of variance (ANOVA) were performed (p < 0.05; 95% confidence interval). Results: In between-group comparisons, there was no significant difference observed in the number of CFUs at the initial (p >< 0.001) and final collections (p >< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies.>< 0.05; 95% confidence interval). Results: In between-group comparisons, there was no significant difference observed in the number of CFUs at the initial (p < 0.001) and final collections (p >< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies.>< 0.001) and final collections (p < 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies>< 0.001) for G2 and G3. In within-group comparisons, the number of CFUs showed a decreasing trend in G4 (p = 0.007) and G5 (p = 0.001). Conclusion: Photosensitizers promoted E. faecalis reduction, with better results for tannin and curcumin. Alternative photosensitizers should be the focus of further studies
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Fotoquimioterapia , Taninos , Fármacos Fotossensibilizantes , Curcumina , EndodontiaRESUMO
Curcumin-mediated Photodynamic Inactivation (PDI) has shown great potential to disinfect specific sites on tooth enamel but may involve contact with restorative materials. Thus, before use in dentistry, it is necessary to investigate whether the PDI protocol causes undesirable changes in the surfaces of aesthetic restorative materials and dental enamel. This study investigated the effect of PDI mediated by curcumin (CUR) in a liquid crystal precursor system on color stability (ΔE), surface roughness (Ra), and microhardness (kgf) of three different composite resins and bovine dental enamel specimens. The microhardness and roughness readings were performed 60 days after the treatments while the color readings were performed immediately, 24, 48, and 72 h, 7, 14, 21, 30, and 60 days after the treatments. Results showed that CUR mediated-PDI does not seem to have the potential to promote any esthetic or mechanical changes to the surface of tooth enamel and can be applied safely in clinical practice. However, the results on color, roughness, and hardness obtained for composite resins show that some negative effects can be produced, depending on the type of restorative material; more experiments must be performed with different formulations and, perhaps, with lower concentrations of CUR.
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Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial photodynamic therapy (aPDT) has broad therapeutic applicability. The purpose was to evaluate in vitro the photodynamic inactivation against Propionibacterium acnes (P. acnes) biofilms by using different concentrations of hypericin (Hypericum perforatum) photosensitizer associated with different energies of low-level laser. The biofilms were placed in 96-well microplates with a 6.4-mm diameter surface, by using standard suspensions (2 × 107 CFU/mL) and grown in brain heart infusion broth (BHI) for 48 h in anaerobic chamber. Subsequently, the control group received application of 0.9% sterile saline solution for 3 min; the photosensitising groups received hypericin at concentrations of 5 and 15 µg/mL for 3 min; the laser groups received irradiation of energies of 3 and 5 J (660 nm, continuous output, 100 mW, 30 and 50 s and 100 J/cm2 and 166 J/cm2, respectively); the aPDT groups received 5 and 15 µg/mL concentrations of hypericin associated with energies of 3 and 5 J of low-level laser irradiation. After the biofilms were broken up and seeded for CFU counting. The results showed a reduction in P. acnes biofilms after aPDT emphasising that 15 µg/mL hypericin associated with 3 and 5 J laser irradiation reduced biofilms by 14.1 and 27.9%, respectively. In addition, all groups of aPDT demostrated statistically significant reductions. In vitro photodynamic inactivation against P. acnes biofilms using different concentration of hypericin photosensitizer associated with different energies of low-level laser promoted effective antimicrobial action.
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Fotoquimioterapia , Acne Vulgar/tratamento farmacológico , Antracenos , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Biofilmes/efeitos da radiação , Humanos , Hypericum , Lasers , Luz , Perileno/análogos & derivados , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Propionibacterium acnesRESUMO
AIMS: A review of analytical methods for the determination of hypericin in foods, herbal, biological and pharmaceutical matrices. BACKGROUND: Hypericin (HYP) is a naturally-occurring pigment obtained from some plants of the genus Hypericum. Although HYP has been known for many years, it has recently attracted attention due to its varied biological properties, such as anti-inflammatory and antidepressant activity and it is also an efficient photosensitizer. OBJECTIVE: The objective of this review is to provide insights into the physicochemical properties of HYP, as well as to report the analytical methods existing in the literature and official compendia for different matrices. METHODS: The survey data were collected by Google Scholar® and Scopus® using keys terms. RESULT: Analytical methods involving HYP are mainly concerned with the quality control of pharmaceutical preparations, foods, beverages, biological samples and drug delivery systems using different types of analysis methods. Some difficulties have also been identified due to the physicochemical properties of HYP. It presents great solubility in alkaline solutions, organic bases and common polar organic solvents. CONCLUSION: It can be analyzed by thin layer chromatography, spectrophotometry in the ultraviolet region, but the most commonly used method is by HPLC. HYP presents monographs in the American, British and European Pharmacopoeias, however, the methods of analysis are not yet harmonized.
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Hypericum , Perileno , Preparações Farmacêuticas , Antracenos , Humanos , Perileno/análogos & derivados , Fármacos FotossensibilizantesRESUMO
BACKGROUND: Although bioactive metabolites capable of causing oxidative photo-necrosis in plant tissues have been identified in fungi, little is known about this type of mechanism in bacteria. These metabolites act as photosensitizers that generate reactive oxygen species (ROS) capable of causing damage to cells. In addition, these metabolites can pass into an energetically excited state when they receive some luminous stimulus, a condition in which they interact with other molecules present in the environment, such as molecular oxygen (O2), also known as triplet oxygen (3 O2), generating ROS. RESULTS: The suspension of the bacterial culture of Pseudomonas cedrina was shown to produce foliar necrosis in papaya leaves (Carica papaya L.) only in the presence of sunlight, which is evidence of photosensitizing mechanisms that generate singlet oxygen (1 O2). From the chemical study of extracts obtained from this bacteria, 3-(4-(2-carboxipropyl) phenyl) but-2-enoic acid (1) was isolated. This compound, in the presence of light and triplet oxygen (3 O2), was able to oxidize ergosterol to its peroxide, since it acted as a photosensitizer producing 1 O2, with which it was corroborated that a photosensitization reaction occurs, mechanism by which this bacterium could prove to cause oxidative foliar photo-necrosis. CONCLUSIONS: P. cedrina was able to induce oxidative foliar photo-necrosis because of its potential ability to produce photosensitizing metabolites that generate singlet oxygen in the plants it colonizes. Based on the above, it can be proposed that some bacteria can cause oxidative foliar photo-necrosis as an important mechanism in the pathogenesis of host species.
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Doenças das Plantas/microbiologia , Pseudomonas/fisiologia , Carica/microbiologia , Oxigênio Singlete/metabolismo , Pseudomonas/metabolismo , Ácidos , Espécies Reativas de Oxigênio , Folhas de Planta/microbiologia , Foto-Oxidação , Luz , NecroseRESUMO
BACKGROUND: This double-blind, randomized, controlled clinical trial assessed the efficacy of multiple sessions of antimicrobial photodynamic therapy (aPDT) as an adjunct to surgical periodontal treatment (ST) in patients with severe chronic periodontitis (SCP). METHODS: Sixteen patients with SCP were treated with aPDT+ST (test group, TG) or ST only (control group, CG), in a split-mouth design. aPDT was applied at 0, 2, 7, and 14 postoperative days only in TG. All patients were followed up for 90 days after surgery. The following clinical and microbiological parameters were assessed: clinical attachment level (CAL), probing depth (PD), gingival recession (GR), bleeding on probing (BOP), plaque index (PI), and count of 40 subgingival microbial species (checkerboard DNA-DNA hybridization). Data were collected at baseline (preintervention), at 60 days (30 days after the end of non-surgical therapy), and at 150 days (90 days after surgery). RESULTS: A significant reduction in PD was observed at 150 days for the TG, when compared with the CG (P Ë 0.05). CAL gain was significantly higher in the TG at 60 and 150 days (P Ë 0.05). Changes in the subgingival microbiota were similar between the groups (P Ë 0.05), but the TG revealed a larger number of bacteria associated with periodontal disease at the end of the experiment compared with the CG (P < 0.05). CONCLUSION: Multiple sessions of aPDT as an adjunct to surgical periodontal treatment significantly improved clinical parameters at 90 postoperative days.
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Anti-Infecciosos , Periodontite Crônica , Fotoquimioterapia , Terapia Combinada , Raspagem Dentária , Método Duplo-Cego , Humanos , Perda da Inserção Periodontal , Fármacos FotossensibilizantesRESUMO
Photodynamic therapy (PDT) is an anticancer therapy that associates the photosensitizer (PS), oxygen and light to destroy cancer cells. Methylene blue (MB) is considered a second generation phenothiazine dye with excellent photochemical properties. Aim: To evaluate whether MB-mediated PDT can induce oxidative stress and inflammation, therefore, interfering tumor growth. Materials and Methods: The study was conducted on Wistar rats transplanted with Walker 256 carcinosarcoma (W256). The proinflammatory interleukins levels (IL-1ß, IL-6, IL-10, TNF-a) were determined by ELISA, mRNA expression of COX-1, COX-2, iNOS and eNOS by RT-PCR, lipid peroxidation was measured by the TBARS method. Moreover, myeloperoxidase (MPO) activity in neutrophils was determined by MPO activity assay. All indices mentioned above were determined in tumor tissue. Kaplan — Meier and Gehan — Breslow — Wilcoxon tests were used for survival analysis. Results: We found that the treatment of W256 with 0.1% MB + 1 J/cm2 provoked a significant increase in the interleukins levels (IL-1ß, IL-6, IL-10, TNF-a), prostaglandin E2, the mRNA expression of COX-2, iNOS, lipid peroxidation and MPO activity in tumor tissue, which were statistically different (p < 0.05) compared to other experimental and control groups. The results of the estimation of survival curves show a greater probability of survival in 0.1% MB + 1 J/cm2 (total energy dose =142.8 J/cm2 ) treated group. Conclusion: Our results suggest that treatment of W256 with 0.1% MB + 1 J/cm2 was able to promote cytotoxic effects in tumor tissue by the generation of reactive oxygen species causing inflammation and thus interfering in the tumor growth
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AIM: This randomized controlled clinical trial evaluated the effects of an adjunctive single application of antimicrobial photodynamic therapy (aPDT) in Surgical Periodontal Treatment (ST) in patients with severe chronic periodontitis (SCP). MATERIAL AND METHODS: In a split-mouth design, 20 patients with SCP were treated with aPDT+ST (Test Group, TG) or ST only (Control Group, CG). aPDT was applied in a single episode, using a diode laser and a phenothiazine photosensitizer. All patients were monitored until 90 days after surgical therapy. Levels of 40 subgingival species were measured by checkerboard DNA-DNA hybridization at baseline, 60 and 150 days. Clinical and microbiological parameters were evaluated. RESULTS: In deep periodontal pockets depth (PPD ≥5 mm), Test Group presented a significantly higher decrease in PPD than Control Group at 90 days after surgical therapy (p < .05). Test Group also demonstrated significantly less periodontal pathogens of red complex (Treponema denticola) (p < .05). CONCLUSION: A single episode of aPDT used in adjunct to open flap debridement of the root surface in the surgical treatment of SCP: i) significantly improved clinical periodontal parameters; ii) eliminates periodontal pathogens of the red complex more effectively (NCT02734784).
Assuntos
Periodontite Crônica/microbiologia , Periodontite Crônica/terapia , Procedimentos Cirúrgicos Bucais/métodos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Adulto , Idoso , Terapia Combinada , Sondas de DNA , Feminino , Humanos , Lasers Semicondutores , Masculino , Pessoa de Meia-Idade , Resultado do TratamentoRESUMO
Composite resins are predominantly marketed in developing countries in tube form, and the contents of the tube may be used in numerous procedures for different patients. This represents a problem because of the risk of cross-contamination. This study aimed to evaluate contamination in vitro of the internal contents of composite resin tubes in the dental clinics of a higher-education institution, as well as the effect of photoactivation on the level of contamination. Twenty-five tubes containing composite resin were randomly chosen (by lottery). From each tube, two samples of approximately 2 mm of composite resin were removed, and then one sample, but not the other, was photoactivated. These samples were plated on Brain-Heart Infusion (BHI), Sabouraud and MacConkey agars, and the plates were incubated at 37°C for 24-48 h. Colony counting and Gram staining were performed for subsequent microscopic identification of fungi and bacteria. The non-photoactivated composite resin group presented significantly higher microbial contamination in relation to the photoactivated composite resin group. The photoactivation of camphorquinone present in composite resin produces reactive oxygen species, which might promote cell death of contaminant microorganisms. Thus, although the same tube of composite resin may be used for a number of different patients in the dental clinics of developing countries, the photoactivation process potentially reduces the risk of cross-contamination.
Assuntos
Resinas Compostas/uso terapêutico , Bactérias , Lâmpadas de Polimerização Dentária , HumanosRESUMO
Abstract: BACKGROUND: Dermatophytes are filamentous keratinophilic fungi. Trichophyton rubrum is a prevalent infectious agent in tineas and other skin diseases. Drug therapy is considered to be limited in the treatment of such infections, mainly due to low accessibility of the drug to the tissue attacked and development of antifungal resistance in these microorganisms. In this context, Photodynamic Therapy is presented as an alternative. OBJECTIVE: Evaluate, in vitro, the photodynamic activity of four derivatives of Protoporphyrin IX by irradiation with LED 400 nm in T. rubrum. METHOD: Assays were subjected to irradiation by twelve cycles of ten minutes at five minute intervals. RESULT: Photodynamic action appeared as effective with total elimination of UFCs from the second irradiation cycle. CONCLUSION: Studies show that the photodynamic activity on Trichophyton rubrum relates to a suitable embodiment of the photosensitizer, which can be maximized by functionalization of peripheral groups of the porphyrinic ring.
Assuntos
Fotoquimioterapia/métodos , Protoporfirinas , Trichophyton/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Valores de Referência , Fatores de Tempo , Tinha/tratamento farmacológico , Contagem de Colônia Microbiana , Reprodutibilidade dos Testes , Análise de Variância , Arthrodermataceae/efeitos dos fármacos , Antifúngicos/farmacologiaRESUMO
In recent years there have been an increasing number of in vitro and in vivo studies that show positive results regarding antimicrobial photodynamic therapy (aPDT) used in dentistry. These include applications in periodontics, endodontics, and mucosal infections caused by bacteria present as biofilms. Antimicrobial photodynamic therapy is a therapy based on the combination of a non-toxic photosensitizer (PS) and appropriate wavelength visible light, which in the presence of oxygen is activated to produce reactive oxygen species (ROS). ROS induce a series of photochemical and biological events that cause irreversible damage leading to the death of microorganisms. Many light-absorbing dyes have been mentioned as potential PS for aPDT and different wavelengths have been tested. However, there is no consensus on a standard protocol yet. Thus, the goal of this review was to summarize the results of research on aPDT in dentistry using the PubMed database focusing on recent studies of the effectiveness aPDT in decreasing microorganisms and microbial biofilms, and also to describe aPDT effects, mechanisms of action and applications.
RESUMO
O tratamento da doença periodontal consiste na remoção mecânica do biofilme,sendo que terapias complementares como a terapia fotodinâmica antimicrobiana(aPDT) podem melhorar os resultados obtidos. Este trabalho avaliou in vitro o efeitodos corantes azul de toluidina e azul de metileno com distintos parâmetros de laser(70; 100mW) e LED em Aggregatibacter actinomycetemcomitans (A.a) emsuspensão. O primeiro experimento avaliou efeito bactericida de diferentesconcentrações dos dois corantes sozinhos (0,05; 0,1; 0,5, 1,0; 2,0; 5,0; 10 mg/ml). Osegundo foi dividido nos seguintes grupos: controles positivo e negativo(gentamicina), grupos somente com luz aplicada, grupos com três concentrações(0,05; 0,1; 10 mg/ml) de corante sozinhos ou associados ao laser de baixaintensidade (660 nm; 2,91 e 4,16 W/cm2; 70 e 100mW; 45 J/cm2; 0,024 cm2; 12 e18s) e LED (627 ± 10 nm; 150mW/cm2; 10,5 mW; 20 J/cm2; 0,07cm2; 123s). Osdados foram analisados pelo teste ANOVA complementado por Tukey (p<0,05). Osresultados demonstraram que ambos os corantes na concentração de 10 mg/mlsozinhos ou associados com laser (ambas as potências) ou LED causaram 100 %de morte bacteriana semelhante ao controle negativo (p>0,05). Com isso, pode-seconcluir que aPDT pode eliminar o A.a. de forma dependente da concentração docorante.(AU(
The main treatment of periodontal disease is the mechanical removal of biofilm.Adjuvant therapies as antimicrobial photodynamic therapy (aPDT) may offer betterresults. The aim of this in vitro study was to evaluate the effect of toluidine andmethylene blue dyes, associated to red laser (70; 100mW) and LED on elimination ofa suspension of Aggregatibacter actinomycetemcomitans (A.a). A first test evaluatedthe bactericidal effect of various concentrations of both dyes (0.05; 0.1; 0.5, 1.0; 2.0;5.0, 10 mg/ml) in absence of light. In the second test, the experimental groupsconsisted of positive and negative (gentamicin) controls, groups with threeconcentrations (0.05; 0.1,10 mg/ml) of dyes alone of associated to low level laser(660 nm; 2.91 and 4.16 W/cm2; 70 and 100mW; 45 J/cm2; 0.024 cm2; 12 and 18s)and LED (627 ± 10 nm; 150mW/cm2; 10.5 mW; 20 J/cm2; 0.07cm2; 123s). Data wereanalyzed by ANOVA complemented by Tukeys test (p<0.05). The results showedthat both dyes, with 10 mg/ml, alone or associated to laser and LED caused 100% ofdeath as the negative control (p>0.05). It can be concluded that aPDT is capable ofeliminate A.a depending of the dye concentration.