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1.
Photodiagnosis Photodyn Ther ; : 101676, 2020 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-32001331

RESUMO

Since Leishmania parasites exhibit new resistance outbreaks to drugs conventionally used in medical treatments, research of new antileishmanial compounds or alternative treatment therapies is essential. A focus of interest has been the implementation of light-based therapies such as photodynamic therapy, where inorganic compounds such as titanium dioxide have shown promising results as drug delivery carriers. In this work, nanoparticles of TiO2 doped with Zn (TiO2/Zn) were synthesized through solution combustion route and with hypericin (HY) in order to enhance its photodynamic activity in the visible light region. Scanning (SEM) and transmission (TEM) electron microscopy analyses showed particles of (TiO2/Zn) with sizes smaller than 20 nm and formation of aggregates smaller than 1 µm, whilst electron diffraction spectroscopy (EDS) analysis ensured the presence of Zn in the system. The association of the TiO2/Zn with HY (TiO2/Zn-HY) was further confirmed by fluorescence spectrometry. Measurements of its cellular uptake showed the presence of smaller molecules into promastigotes after 120 min incubation. TiO2/Zn-HY showed good antileishmanial activity (EC50 of 17.5 ± 0.2 µg mL-1) and low cytotoxicity against murine macrophages (CC50 35.2 ± 0.3 µg mL-1) in the visible light (22 mW cm-2; 52.8 J cm-2). Moreover, in the in vivo analysis, TiO2/Zn-HY decreased the parasite load of L. amazonensis - BALB/c infected mice by 43% to 58% after a combination of blue and red light presenting 22 mW cm-2 of potency and 52.8 J cm-2 of energy delivered. All together, these data indicate a new combined system of nanoparticles associated with a photosensitizer and PDT as alternative to amphotericin B for the treatment of cutaneous leishmaniasis.

2.
Mater Sci Eng C Mater Biol Appl ; 108: 110462, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31923986

RESUMO

Breast cancer is a serious public health problem that causes thousands of deaths annually. Chemotherapy continues to play a central role in the management of breast cancer but is associated with extreme off-target toxicity. Therefore, treatments that directly target the tumor and display reduced susceptibility to resistance could improve the outcome and quality of life for patients suffering from this disease. Photodynamic therapy is a targeted treatment based on the use of light to activate a photosensitizer (PS) that then interacts with molecular oxygen and other biochemical substrates to generate cytotoxic levels of Reactive Oxygen Species. Currently approved PS also tends to have poor aqueous solubility that can cause problems when delivered intravenously. In order to circumvent this limitation, in this manuscript, we evaluate the potential of a phthalocyanine-loaded nanostructured lipid carrier (NLC) functionalized with folic acid (FA). To prepare the FA labelled NLC, the polymer PF127 was first esterified with FA and emulsified with an oil phase containing polyoxyethylene 40 stearate, capric/caprylic acid triglycerides, ethoxylated hydrogenated castor oil 40 and the PS zinc phthalocyanine. The resulting PS loaded FA-NLC had a hydrodynamic diameter of 180 nm and were stable in suspension for >90 days. Interestingly, the amount of singlet oxygen generated upon light activation for the PS loaded FA-NLC was substantially higher than the free PS, yet at a lower PS concentration. The PS was released from the NLC in a sustained manner with 4.13 ±â€¯0.58% and 27.7 ±â€¯3.16% after 30 min and 7 days, respectively. Finally, cytotoxicity assays showed that NLC in the concentrations of 09.1 µM of PS present non-toxic with >80 ±â€¯6.8% viable and after 90 s of the light-exposed the results show a statistically significant decrease in cell viability (57 ±â€¯4%). The results obtained allow us to conclude that the functionalized NLC incorporated with PS associated with the PDT technique have characteristics that make them potential candidates for the alternative treatment of breast cancer.

3.
Biofouling ; 35(7): 742-757, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31550929

RESUMO

The self-produced extracellular polymeric matrix of biofilms renders them difficult to eliminate once they are established. This makes the inhibition of biofilm formation key to successful treatment of biofilm infection. Antimicrobial photodynamic therapy (aPDT) and antimicrobial peptides offer a new approach as antibiofilm strategies. In this study sub-lethal doses of aPDT (with chlorin-e6 (Ce6-PDT) or methylene blue (MB-PDT)) and the peptides AU (aurein 1.2 monomer) or (AU)2K (aurein 1.2 C-terminal dimer) were combined to evaluate their ability to prevent biofilm development by Enterococcus faecalis. Biofilm formation was assessed by resazurin reduction, confocal microscopy, and infrared spectroscopy. All treatments successfully prevented biofilm development. The (AU)2K dimer had a stronger effect, both alone and combined with aPDT, while the monomer AU had significant activity when combined with Ce6-PDT. Additionally, it is shown that the peptides bind to the lipoteichoic acid of the E. faecalis cell wall, pointing to a possible key mechanism of biofilm inhibition.


Assuntos
Antibacterianos/química , Biofilmes , Peptídeos/química , Fármacos Fotossensibilizantes/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/fisiologia , Peptídeos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/química
4.
Int J Mol Sci ; 20(16)2019 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398812

RESUMO

Recent scientific research has shown the use of chlorin, phthalocyanines, and porphyrins derivatives as photosensitizers in photodynamic therapy in the treatment of various pathologies, including some of the major skin diseases. Thus, the main goal of this critical review is to catalog the papers that used these photosensitizers in the treatment of acne vulgaris, psoriasis, papillomavirus infections, cutaneous leishmaniasis, and skin rejuvenation, and to explore the photodynamic therapy mechanisms against these conditions alongside their clinical benefits.


Assuntos
Indóis/uso terapêutico , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Dermatopatias/tratamento farmacológico , Pele/efeitos dos fármacos , Animais , Humanos , Indóis/farmacologia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Porfirinas/farmacologia , Pele/patologia , Dermatopatias/diagnóstico , Dermatopatias/etiologia , Resultado do Tratamento
5.
Int J Mol Sci ; 20(14)2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31340425

RESUMO

The aim of this study was to perform a systematic review of the literature followed by a meta-analysis about the efficacy of photodynamic therapy (PDT) on the microorganisms responsible for dental caries. The research question and the keywords were constructed according to the PICO strategy. The article search was done in Embase, Lilacs, Scielo, Medline, Scopus, Cochrane Library, Web of Science, Science Direct, and Pubmed databases. Randomized clinical trials and in vitro studies were selected in the review. The study was conducted according the PRISMA guideline for systematic review. A total of 34 articles were included in the qualitative analysis and four articles were divided into two subgroups to perform the meta-analysis. Few studies have achieved an effective microbial reduction in microorganisms associated with the pathogenesis of dental caries. The results highlight that there is no consensus about the study protocols for PDT against cariogenic microorganisms, although the results showed the PDT could be a good alternative for the treatment of dental caries.


Assuntos
Infecções por Bacteroidaceae/tratamento farmacológico , Candidíase/tratamento farmacológico , Cárie Dentária/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Infecções Estreptocócicas/tratamento farmacológico , Infecções por Bacteroidaceae/microbiologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida/efeitos dos fármacos , Candida/crescimento & desenvolvimento , Candida/patogenicidade , Candidíase/microbiologia , Curcumina/farmacologia , Cárie Dentária/microbiologia , Humanos , Azul de Metileno/farmacologia , Porphyromonas gingivalis/efeitos dos fármacos , Porphyromonas gingivalis/crescimento & desenvolvimento , Porphyromonas gingivalis/patogenicidade , Corantes de Rosanilina/farmacologia , Infecções Estreptocócicas/microbiologia , Streptococcus/efeitos dos fármacos , Streptococcus/crescimento & desenvolvimento , Streptococcus/patogenicidade , Cloreto de Tolônio/farmacologia , Resultado do Tratamento
6.
AAPS PharmSciTech ; 20(7): 253, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31309346

RESUMO

Drug delivery systems (DDS) can be designed to enrich the pharmacological and therapeutic properties of several drugs. Many of the initial obstacles that impeded the clinical applications of conventional DDS have been overcome with nanotechnology-based DDS, especially those formed by chitosan (CS). CS is a linear polysaccharide obtained by the deacetylation of chitin, which has potential properties such as biocompatibility, hydrophilicity, biodegradability, non-toxicity, high bioavailability, simplicity of modification, aqueous solubility, and excellent chemical resistance. Furthermore, CS can prepare several DDS as films, gels, nanoparticles, and microparticles to improve delivery of drugs, such as photosensitizers (PS). Thus, CS-based DDS are broadly investigated for photodynamic therapy (PDT) of cancer and fungal and bacterial diseases. In PDT, a PS is activated by light of a specific wavelength, which provokes selective damage to the target tissue and its surrounding vasculature, but most PS have low water solubility and cutaneous photosensitivity impairing the clinical use of PDT. Based on this, the application of nanotechnology using chitosan-based DDS in PDT may offer great possibilities in the treatment of diseases. Therefore, this review presents numerous applications of chitosan-based DDS in order to improve the PDT for cancer and fungal and bacterial diseases.


Assuntos
Quitosana/química , Sistemas de Liberação de Medicamentos , Fotoquimioterapia , Fármacos Fotossensibilizantes/administração & dosagem , Infecções Bacterianas/tratamento farmacológico , Humanos , Micoses/tratamento farmacológico , Nanopartículas/química , Neoplasias/tratamento farmacológico , Fármacos Fotossensibilizantes/química , Polissacarídeos
7.
AAPS PharmSciTech ; 20(6): 225, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31214798

RESUMO

The vaginal mucosa is a very promising route for drug administration due to its high permeability and the possibility to bypass first pass metabolism; however, current vaginal dosage forms present low retention times due to their dilution in vaginal fluids, which hampers the efficacy of many pharmacological treatments. In order to overcome these problems, this study proposes to develop a mucoadhesive in situ gelling liquid crystalline precursor system composed of 30% of oleic acid and cholesterol (7:1), 40% of ethoxylated and propoxylated cetyl alcohol, and 30% of a dispersion of 16% Poloxamer 407. The effect of the dilution with simulated vaginal fluid (SVF) on this system was evaluated by polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), rheological studies, texture profile analysis (TPA), mucoadhesion study, in vitro drug release test using hypericin (HYP) as drug model, and cytotoxicity assay. PLM and SAXS confirmed the formation of an isotropic system. After the addition of three different concentrations of SVF (30, 50, and 100%), the resultant formulations presented anisotropy and characteristics of viscous lamellar phases. Rheology shows that formulations with SVF behaved as a non-Newtonian fluid with suitable shear thinning for vaginal application. TPA and mucoadhesion assays indicated the formation of long-range ordered systems as the amount of SVF increases which may assist in the fixation of the formulation on the vaginal mucosa. The formulations were able to control about 75% of the released HYP demonstrating a sustained release profile. Finally, all formulations acted as safe vaginal drug delivery systems.


Assuntos
Administração Intravaginal , Géis/metabolismo , Membrana Mucosa/metabolismo , Animais , Líquidos Corporais , Cristalização , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Feminino , Poloxâmero/metabolismo , Reologia , Espalhamento a Baixo Ângulo , Vagina , Viscosidade , Difração de Raios X
8.
Clin Exp Dent Res ; 4(1): 19-24, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29744211

RESUMO

The prevalence profile of periodontal pathogens in dental plaque can vary as a function of the detection method; however, the sampling technique may also play a role in determining dental plaque microbial profiles. We sought to determine the bacterial composition comparing two sampling methods, one well stablished and a new one proposed here. In this study, a ligature-induced periodontitis model was used in 30 rats. Twenty-seven days later, ligatures were removed and microbiological samples were obtained directly from the ligatures as well as from the periodontal pockets using absorbent paper points. Microbial analysis was performed using DNA probes to a panel of 40 periodontal species in the checkerboard assay. The bacterial composition patterns were similar for both sampling methods. However, detection levels for all species were markedly higher for ligatures compared with paper points. Ligature samples provided more bacterial counts than paper points, suggesting that the technique for induction of periodontitis could also be applied for sampling in rats. Our findings may be helpful in designing studies of induced periodontal disease-associated microbiota.

9.
Sci Rep ; 8(1): 4212, 2018 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-29523862

RESUMO

In the past few years, the World Health Organization has been warning that the post-antibiotic era is an increasingly real threat. The rising and disseminated resistance to antibiotics made mandatory the search for new drugs and/or alternative therapies that are able to eliminate resistant microorganisms and impair the development of new forms of resistance. In this context, antimicrobial photodynamic therapy (aPDT) and helical cationic antimicrobial peptides (AMP) are highlighted for the treatment of localized infections. This study aimed to combine the AMP aurein 1.2 to aPDT using Enterococcus faecalis as a model strain. Our results demonstrate that the combination of aPDT with aurein 1.2 proved to be a feasible alternative capable of completely eliminating E. faecalis employing low concentrations of both PS and AMP, in comparison with the individual therapies. Aurein 1.2 is capable of enhancing the aPDT activity whenever mediated by methylene blue or chlorin-e6, but not by curcumin, revealing a PS-dependent mechanism. The combined treatment was also effective against different strains; noteworthy, it completely eliminated a vancomycin-resistant strain of Enterococcus faecium. Our results suggest that this combined protocol must be exploited for clinical applications in localized infections as an alternative to antibiotics.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Transporte Biológico , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Membrana Celular/efeitos da radiação , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos da radiação , Sinergismo Farmacológico , Enterococcus faecalis/citologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/metabolismo , Enterococcus faecalis/efeitos da radiação , Humanos , Espécies Reativas de Oxigênio/metabolismo
10.
Molecules ; 23(2)2018 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-29470387

RESUMO

Chitosan (CH) is a biopolymer that exhibits a number of interesting properties such as anti-inflammatory and antibacterial activity and is also a promising platform for the incorporation of photosensitizing agents. This study aimed to evaluate the efficacy of antimicrobial activity of chitosan hydrogel formulation alone and in combination with the methylene blue (MB) associated with antimicrobial photodynamic therapy (aPDT) against planktonic and biofilm phase of Propionibacterium acnes. Suspensions were sensitized with 12.5, 25.0, 37.5, 50.0 µg/mL of MB for 10 min and biofilms to 75, 100 and 150 µg/mL for 30 min then exposed to red light (660 nm) at 90 J/cm² and 150 J/cm² respectively. After treatments, survival fractions were calculated by counting the number of colony-forming units. The lethal effect of aPDT associated with CH hydrogel in planktonic phase was achieved with 12.5 µg/mL MB and 1.9 log10 biofilm reduction using 75 µg/mL MB. Rheological studies showed that formulations exhibited pseudoplastic non-Newtonian behavior without thixotropy. Bioadhesion test evidenced that the formulations are highly adhesive to skin and the incorporation of MB did not influence the bioadhesive force of the formulations.


Assuntos
Anti-Infecciosos/química , Quitosana/química , Hidrogel de Polietilenoglicol-Dimetacrilato/química , Propionibacterium acnes/efeitos dos fármacos , Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Quitosana/farmacologia , Humanos , Hidrogel de Polietilenoglicol-Dimetacrilato/farmacologia , Azul de Metileno/química , Fotoquimioterapia , Propionibacterium acnes/patogenicidade , Reologia
11.
J Photochem Photobiol B ; 178: 545-550, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29253813

RESUMO

Bacterial resistance to available antibiotics nowadays is a global threat leading researchers around the world to study new treatment modalities for infections. Antimicrobial photodynamic therapy (aPDT) has been considered an effective and promising therapeutic alternative in this scenario. Briefly, this therapy is based on the activation of a non-toxic photosensitizing agent, known as photosensitizer (PS), by light at a specific wavelength generating cytotoxic singlet oxygen and free radicals. Virtually all studies related to aPDT involve a huge screening to identify ideal PS concentration and light dose combinations, a laborious and time-consuming process that is hardly disclosed in the literature. Herein, we describe an antimicrobial Photodynamic Therapy (aPDT) study against Enterococcus faecalis and Propionibacterium acnes employing methylene blue, chlorin-e6 or curcumin as PS. Similarities and discrepancies between the two bacterial species were pointed out in an attempt to speed up and facilitate futures studies against those clinical relevant strains. Susceptibility tests were performed by the broth microdilution method. Our results demonstrate that aPDT mediated by the three above-mentioned PS was effective in eliminating both gram-positive bacteria, although P. acnes showed remarkably higher susceptibility to aPDT when compared to E. faecalis. PS uptake assays revealed that P. acnes is 80 times more efficient than E. faecalis in internalizing all three PS molecules. Our results evidence that the cell wall structure is not a limiting feature when predicting bacterial susceptibility to aPDT treatment.


Assuntos
Anti-Infecciosos/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Fármacos Fotossensibilizantes/farmacologia , Propionibacterium acnes/efeitos dos fármacos , Anti-Infecciosos/química , Curcumina/química , Curcumina/farmacologia , Enterococcus faecalis/efeitos da radiação , Luz , Azul de Metileno/química , Azul de Metileno/farmacologia , Fármacos Fotossensibilizantes/química , Porfirinas/química , Porfirinas/farmacologia , Propionibacterium acnes/efeitos da radiação , Oxigênio Singlete/química , Oxigênio Singlete/metabolismo
12.
Photomed Laser Surg ; 35(7): 378-385, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28621579

RESUMO

BACKGROUND: One of the main mechanisms of microbial resistance is given by efflux pumps, which reduce the effectiveness of antimicrobials by decreasing their intracellular concentration. OBJECTIVE AND METHODS: Considering that efflux pump inhibitors are promising adjuvant molecules for antibiotics in infections, in this study, using XTT test and colony forming unit (CFU) counting, we evaluated the association between the pump inhibitor verapamil (VP) and the antimicrobial photodynamic therapy (aPDT) mediated by methylene blue (MB) in biofilms of Escherichia coli and Staphylococcus aureus to optimize the bacterial reduction. RESULTS: By applying 44 J/cm2, 215 µg/mL of VP, and 200 µg/mL of MB, we obtained 80% of metabolism reduction and 3.4 log10 CFU/mL decrease for E. coli. Biofilm of S. aureus presented 80% of metabolism reduction and 3.65 log10 CFU/mL decrease when 22 J/cm2, 312 µg/mL of VP, and 200 µg/mL of MB was used. Applying 200 µg/mL of MB, the E. coli biofilm required a higher dose of light, while the S. aureus biofilm required a higher concentration of VP to obtain the same reduction. CONCLUSIONS: The VP optimized the efficiency of aPDT and showed no toxicity when used alone in both strains, proving that inhibiting efflux pumps in combination with aPDT has great potential for clinical application.


Assuntos
Anti-Infecciosos/farmacologia , Biofilmes/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Fotoquimioterapia/métodos , Staphylococcus aureus/efeitos dos fármacos , Verapamil/farmacologia , Escherichia coli/fisiologia , Humanos , Amostragem , Sensibilidade e Especificidade , Staphylococcus aureus/fisiologia
13.
BMC Cancer ; 17(1): 123, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28187758

RESUMO

BACKGROUND: Photodynamic therapy (PDT) has proven to be a promising alternative to current cancer treatments, especially if combined with conventional approaches. The technique is based on the administration of a non-toxic photosensitizing agent to the patient with subsequent localized exposure to a light source of a specific wavelength, resulting in a cytotoxic response to oxidative damage. The present study intended to evaluate in vitro the type of induced death and the genotoxic and mutagenic effects of PDT alone and associated with cisplatin. METHODS: We used the cell lines SiHa (ATCC® HTB35™), C-33 A (ATCC® HTB31™) and HaCaT cells, all available at Dr. Christiane Soares' Lab. Photosensitizers were Photogem (PGPDT) and methylene blue (MBPDT), alone or combined with cisplatin. Cell death was accessed through Hoechst and Propidium iodide staining and caspase-3 activity. Genotoxicity and mutagenicity were accessed via flow cytometry with anti-gama-H2AX and micronuclei assay, respectively. Data were analyzed by one-way ANOVA with Tukey's posthoc test. RESULTS: Both MBPDT and PGPDT induced caspase-independent death, but MBPDT induced the morphology of typical necrosis, while PGPDT induced morphological alterations most similar to apoptosis. Cisplatin predominantly induced apoptosis, and the combined therapy induced variable rates of apoptosis- or necrosis-like phenotypes according to the cell line, but the percentage of dead cells was always higher than with monotherapies. MBPDT, either as monotherapy or in combination with cisplatin, was the unique therapy to induce significant damage to DNA (double strand breaks) in the three cell lines evaluated. However, there was no mutagenic potential observed for the damage induced by MBPDT, since the few cells that survived the treatment have lost their clonogenic capacity. CONCLUSIONS: Our results elicit the potential of combined therapy in diminishing the toxicity of antineoplastic drugs. Ultimately, photodynamic therapy mediated by either methylene blue or Photogem as monotherapy or in combination with cisplatin has low mutagenic potential, which supports its safe use in clinical practice for the treatment of cervical cancer.


Assuntos
Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Cisplatino/farmacologia , Luz , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/efeitos da radiação , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Histonas/metabolismo , Humanos , Micronúcleos com Defeito Cromossômico/efeitos dos fármacos , Micronúcleos com Defeito Cromossômico/efeitos da radiação , Fosforilação/efeitos dos fármacos , Fosforilação/efeitos da radiação , Fotoquimioterapia/métodos , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia
14.
Photomed Laser Surg ; 35(5): 259-263, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28092483

RESUMO

OBJECTIVE: This investigation assessed the susceptibility of Streptococcus mutans and Lactobacillus acidophilus to Photodynamic Therapy (PDT) when grown simultaneously in dentine carious lesions. BACKGROUND DATA: PDT is a technique that utilizes light to activate photosensitizers in the presence of oxygen to produce reactive radicals. MATERIALS AND METHODS: A culture medium of 1% glucose, 2% sucrose, 1% young primary culture of L. acidophilus 108 CFU/mL, and S. mutans 108 CFU/mL was utilized to inoculate the bacterial induced caries on human dentine slabs. Different concentrations of the photosensitizer (0.75, 1.5, 3.0, 4.0, and 5.0 g/L) were activated through exposure to the light-emitting diode source with a central wavelength of 450 nm and a fluency of 5.7 J/cm2. Two light intensities (19 and 47.5 mW/cm2) were tested. Four different groups were analyzed: L-D- (control group), L-D+ (drug group), L+D+1 (PDT group 1, light intensity of 19 mW/cm2), and L+D+2 (PDT group 2, light intensity of 47.5 mW/cm2). ANOVA/Tukey tests were utilized to compare groups (α = 5%). RESULTS: Both light intensities required 5.0 g/L of curcumin for significant bacterial reduction (p < 0.05). No significant effect was found for L-D+, thus proving the absence of a potential inherent toxicity. CONCLUSIONS: Curcumin has a toxic effect on microorganisms at appreciable concentrations upon photoactivation. However, it was required to use the maximum concentration of the drug for a successful procedure.


Assuntos
Curcumina/farmacologia , Cárie Dentária/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Análise de Variância , Cárie Dentária/microbiologia , Humanos , Técnicas In Vitro , Lactobacillus acidophilus/efeitos dos fármacos , Lactobacillus acidophilus/patogenicidade , Testes de Sensibilidade Microbiana , Dente Molar/efeitos dos fármacos , Dente Molar/microbiologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/patogenicidade
15.
Int J Mol Sci ; 17(8)2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27548153

RESUMO

Controlling microbial growth is crucial for many biomedical, pharmaceutical and food industry applications. In this paper, we used a femtosecond laser to microstructure the surface of chitosan, a biocompatible polymer that has been explored for applications ranging from antimicrobial action to drug delivery. The influence of energy density on the features produced on chitosan was investigated by optical and atomic force microscopies. An increase in the hydrophilic character of the chitosan surface was attained upon laser micromachining. Patterned chitosan films were used to observe Staphylococcus aureus (ATCC 25923) biofilm formation, revealing an increase in the biofilm formation in the structured regions. Our results indicate that fs-laser micromachining is an attractive option to pattern biocompatible surfaces, and to investigate basic aspects of the relationship between surface topography and bacterial adhesion.


Assuntos
Biofilmes/efeitos dos fármacos , Biopolímeros/química , Quitosana/química , Aderência Bacteriana/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biopolímeros/farmacologia , Quitosana/farmacologia , Interações Hidrofóbicas e Hidrofílicas , Microscopia de Força Atômica , Staphylococcus aureus/efeitos dos fármacos
16.
Int J Mol Sci ; 17(5)2016 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-27213356

RESUMO

Antimicrobial photodynamic therapy (aPDT) is increasingly being explored for treatment of periodontitis. Here, we investigated the effect of aPDT on human dental plaque bacteria in suspensions and biofilms in vitro using methylene blue (MB)-loaded poly(lactic-co-glycolic) (PLGA) nanoparticles (MB-NP) and red light at 660 nm. The effect of MB-NP-based aPDT was also evaluated in a clinical pilot study with 10 adult human subjects with chronic periodontitis. Dental plaque samples from human subjects were exposed to aPDT-in planktonic and biofilm phases-with MB or MB-NP (25 µg/mL) at 20 J/cm² in vitro. Patients were treated either with ultrasonic scaling and scaling and root planing (US + SRP) or ultrasonic scaling + SRP + aPDT with MB-NP (25 µg/mL and 20 J/cm²) in a split-mouth design. In biofilms, MB-NP eliminated approximately 25% more bacteria than free MB. The clinical study demonstrated the safety of aPDT. Both groups showed similar improvements of clinical parameters one month following treatments. However, at three months ultrasonic SRP + aPDT showed a greater effect (28.82%) on gingival bleeding index (GBI) compared to ultrasonic SRP. The utilization of PLGA nanoparticles encapsulated with MB may be a promising adjunct in antimicrobial periodontal treatment.


Assuntos
Biofilmes/efeitos dos fármacos , Ácido Láctico/administração & dosagem , Azul de Metileno/administração & dosagem , Nanopartículas , Periodontite/tratamento farmacológico , Periodontite/microbiologia , Fotoquimioterapia/métodos , Ácido Poliglicólico/administração & dosagem , Adulto , Idoso , Feminino , Humanos , Ácido Láctico/química , Masculino , Azul de Metileno/química , Pessoa de Meia-Idade , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico
17.
Molecules ; 21(3): 342, 2016 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-26978341

RESUMO

Photodynamic therapy (PDT) is a promising alternative approach for improved cancer treatment. In PDT, a photosensitizer (PS) is administered that can be activated by light of a specific wavelength, which causes selective damage to the tumor and its surrounding vasculature. The success of PDT is limited by the difficulty in administering photosensitizers (PSs) with low water solubility, which compromises the clinical use of several molecules. Incorporation of PSs in nanostructured drug delivery systems, such as polymeric nanoparticles (PNPs), solid lipid nanoparticles (SLNs), nanostructured lipid carriers (NLCs), gold nanoparticles (AuNPs), hydrogels, liposomes, liquid crystals, dendrimers, and cyclodextrin is a potential strategy to overcome this difficulty. Additionally, nanotechnology-based drug delivery systems may improve the transcytosis of a PS across epithelial and endothelial barriers and afford the simultaneous co-delivery of two or more drugs. Based on this, the application of nanotechnology in medicine may offer numerous exciting possibilities in cancer treatment and improve the efficacy of available therapeutics. Therefore, the aim of this paper is to review nanotechnology-based drug delivery systems for photodynamic therapy of cancer.


Assuntos
Sistemas de Liberação de Medicamentos , Nanotecnologia , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Animais , Humanos , Hidrogéis , Lipossomos , Cristais Líquidos , Nanopartículas/química , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Fármacos Fotossensibilizantes/química
18.
J Photochem Photobiol B ; 158: 122-9, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26971277

RESUMO

The occurrence of a variety of pathogens resistant to current antibiotics remains the major problem in medical care, especially when bacterial infections are established as biofilms. In this study, we propose the use of photodynamic therapy (PDT) as a monotherapy and associated with antibiotic as an alternative treatment. The aim of this study was to analyze the effects of PDT mediated by methylene blue (MB) on Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922) in both biofilm and planktonic phases. Several concentrations of MB and light doses were tested. The bactericidal effects of PDT as a monotherapy did not increase with the concentration of photosensitizer, but were light dose-dependent. In addition, bacteria in biofilms were less affected than cells in the planktonic phase. Although not concentration-dependent, the disruption effect of PDT on biofilms was clearly illustrated by scanning electron microscopy (SEM). We also carried out experiments that evaluated the synergistic effect of photodynamic therapy and the antibiotic ciprofloxacin. The best results were obtained after combination treatment of photodynamic therapy followed by ciprofloxacin on biofilms, which increased bacterial reduction on biofilms, resulting in a 5.4 log reduction for S. aureus biofilm and approximately 7 log for E. coli biofilm.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacino/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Antibacterianos/uso terapêutico , Biofilmes , Ciprofloxacino/uso terapêutico , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Fármacos Fotossensibilizantes/química
19.
Molecules ; 21(1): E37, 2015 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-26712726

RESUMO

Decapeptide KSL-W shows antibacterial activities and can be used in the oral cavity, however, it is easily degraded in aqueous solution and eliminated. Therefore, we aimed to develop liquid crystalline systems (F1 and F2) for KSL-W buccal administration to treat multispecies oral biofilms. The systems were prepared with oleic acid, polyoxypropylene (5) polyoxyethylene (20) cetyl alcohol (PPG-5-CETETH-20), and a 1% poloxamer 407 dispersion as the oil phase (OP), surfactant (S), and aqueous phase (AP), respectively. We characterized them using polarized light microscopy (PLM), small-angle X-ray scattering (SAXS), rheology, and in vitro bioadhesion, and performed in vitro biological analysis. PLM showed isotropy (F1) or anisotropy with lamellar mesophases (F2), confirmed by peak ratio quantification using SAXS. Rheological tests demonstrated that F1 exhibited Newtonian behavior but not F2, which showed a structured AP concentration-dependent system. Bioadhesion studies revealed an AP concentration-dependent increase in the system's bioadhesiveness (F2 = 15.50 ± 1.00 mN·s) to bovine teeth blocks. Antimicrobial testing revealed 100% inhibition of multispecies oral biofilm growth after KSL-W administration, which was incorporated in the F2 aqueous phase at a concentration of 1 mg/mL. Our results suggest that this system could serve as a potential vehicle for buccal administration of antibiofilm peptides.


Assuntos
Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Peptídeos Catiônicos Antimicrobianos/química , Biofilmes/efeitos dos fármacos , Cristais Líquidos/química , Boca/microbiologia , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Bovinos , Excipientes , Boca/efeitos dos fármacos , Espalhamento a Baixo Ângulo , Tensoativos , Difração de Raios X
20.
Photomed Laser Surg ; 32(11): 627-32, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25343373

RESUMO

OBJECTIVE: The purpose of this study was to evaluate the effects of the antimicrobial photodynamic therapy (a-PDT) with blue light and curcumin on oral disinfection during the 2 h after treatment. BACKGROUND DATA: a-PDT is a technique that can potentially affect the viability of bacterial cells, with selective action targeting only areas with photosensitizer accumulation. MATERIALS AND METHODS: A randomized controlled trial was undertaken. Twenty-seven adults were randomly divided into three groups: (1) the PDT group, which was treated with the drug, curcumin, and blue light (n=9); (2) the light group, which was treated only with the blue light, and no drug (n=9) and; (3) the curcumin group, which was treated only with the drug, curcumin, and no light (n=9). The irradiation parameters were: blue light-emitting diode (LED) illumination (455±30 nm), 400 mW of average optical power, 5 min of application, illumination area of 0.6 cm(2), 600 mW/cm(2) of intensity, and 200 J/cm(2) of fluence. A curcumin concentration of 30 mg/L was used. The saliva samples were collected for bacterial counts at baseline and after the experimental phases (immediately after treatment, and 1 and 2 h after treatment). Serial dilutions were performed, and the resulting samples were cultured on blood agar plates in microaerophilic conditions. The number of colony-forming units (CFU) was determined. RESULTS: The PDT group showed a significant reduction of CFU immediately after treatment (post-treatment) with PDT (5.71±0.48, p=0.001), and 1 h (5.14±0.92, p=0.001) and 2 h (5.35±0.76, p=0.001) after treatment, compared with pretreatment (6.61±0.82). There were no significant changes for the light group. The curcumin group showed a significant increase of CFU 1 h after treatment (6.77±0.40, p=0.02) compared with pretreatment (5.57±0.91) falling to baseline values at 2 h after treatment (5.58±0.70). CONCLUSIONS: The PDT group showed significant difference in microbial reduction (p<0.05) compared with both the light and curcumin groups until 2 h post-treatment. The new blue LED device for PDT using curcumin may be used for reduction of salivary microorganisms, leading to overall disinfection of the mouth (e.g., mucosa, tongue, and saliva), but new protocols should be explored.


Assuntos
Curcumina/farmacologia , Desinfecção/métodos , Fotoquimioterapia , Saliva/microbiologia , Adulto , Anti-Infecciosos/farmacologia , Carga Bacteriana , Feminino , Humanos , Masculino , Antissépticos Bucais/química , Fármacos Fotossensibilizantes/farmacologia
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