111 results match your criteria: "Center for Lasers and Applications.[Affiliation]"

Objectives: This study aimed to investigate the influence of Nd:YAG laser and aluminum oxide sandblasting on the shear bond strength (SBS) of lingual brackets and to optically analyze the behavior of the enamel morphology.

Materials And Methods: Thirty-five bovines' incisors teeth were divided into 5 groups (n = 7), according to the surface preconditioning: G1, control group; G2, Nd:YAG laser; G3, laser + aluminum oxide sandblasting (AlO); G4, AlO; and G5, AlO + laser. All groups had lingual brackets bonded and shear debonded after 72 h.

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Global priority multidrug-resistant pathogens do not resist photodynamic therapy.

J Photochem Photobiol B

July 2020

Department of Clinical Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.; Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.

Microbial drug-resistance demands immediate implementation of novel therapeutic strategies. Antimicrobial photodynamic therapy (aPDT) combines the administration of a photosensitizer (PS) compound with low-irradiance light to induce photochemical reactions that yield reactive oxygen species (ROS). Since ROS react with nearly all biomolecules, aPDT offers a powerful multitarget method to avoid selection of drug-resistant strains.

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Surface Evaluation of Enamel Etched by Er,Cr:YSGG Laser for Orthodontic Purpose.

J Contemp Dent Pract

March 2020

Department of Physics, School of Dentistry, Federal University of Pernambuco (UFPE), Recife-PE, Brazil, Phone: +55 8121268000, e-mail:

Aim: To compare the effect of erbium, chromium:yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser at different irradiation parameters and acid etching on the shear bond strength (SBS) of orthodontic brackets to enamel.

Materials And Methods: Forty bovine incisors were randomly distributed into groups ( = 10): GI: 37% phosphoric acid etching; GII: Er,Cr:YSGG laser etching 19.1 J/cm; GIII: Er,Cr:YSGG, 29.

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Cutaneous leishmaniasis (CL) is a neglected disease that promotes destructive lesions. Difficulties in treatment are related to accessibility of drugs, resistance and toxicity. Antimicrobial photodynamic therapy (APDT) has been emerging as a promising treatment for CL.

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Inactivation of milk-borne pathogens by blue light exposure.

J Dairy Sci

February 2020

Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of Sao Paulo, Sao Paulo, SP, Brazil, 05508-000; BioLambda, Scientific and Commercial Ltd., Sao Paulo, SP, Brazil, 05360-030. Electronic address:

Food safety and quality management play a pivotal role in the dairy industry. Milk is a highly nutritious food that also provides an excellent medium for growth of pathogenic microorganisms. Thus, dairy industry focuses most of their processes and costs on keeping contamination levels as low as possible.

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Nitric oxide-loaded chitosan nanoparticles as an innovative antileishmanial platform.

Nitric Oxide

December 2019

Center for Lasers and Applications, Nuclear and Energy Research Institute (IPEN-CNEN/SP), Av. Prof. Lineu Prestes, 2242, CEP 05508-000, São Paulo, SP, Brazil. Electronic address:

Leishmaniasis is a neglected tropical disease that demands for new therapeutic strategies due to adverse side effects and resistance development promoted by current drugs. Nitric oxide (NO)-donors show potential to kill Leishmania spp. but their use is limited because of their instability.

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Inactivation kinetics and lethal dose analysis of antimicrobial blue light and photodynamic therapy.

Photodiagnosis Photodyn Ther

December 2019

Center for Lasers and Applications, Nuclear and Energy Research Institute, National Commission for Nuclear Energy, São Paulo, SP, Brazil.

Background: Antimicrobial Photodynamic therapy (A-PDT) has been used to treat infections. Currently, microbial inactivation data is reported presenting survival fraction averages and standard errors as discrete points instead of a continuous curve of inactivation kinetics. Standardization of this approach would allow clinical protocols to be introduced globally, instead of the piecemeal situation which currently applies.

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Parameters for antimicrobial photodynamic therapy on periodontal pocket-Randomized clinical trial.

Photodiagnosis Photodyn Ther

September 2019

Department of Biophotonics, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil; School of Dentistry, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. Electronic address:

Background: Antimicrobial photodynamic therapy (aPDT) has been investigated as an adjunctive to periodontal treatment but the dosimetry parameters adopted have discrepancies and represent a challenge to measure efficacy. There is a need to understand the clinical parameters required to obtain antimicrobial effects by using aPDT in periodontal pockets. The aim of this study was to investigate parameters relating to the antimicrobial effects of photodynamic therapy in periodontal pockets.

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Effect of photodynamic antimicrobial chemotherapy on Candida albicans in the presence of glucose.

Photodiagnosis Photodyn Ther

September 2019

Dep. of Biophotonics, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil; School of Dentistry, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. Electronic address:

Background: Candida albicans is an opportunistic commensal microorganism, often associated with severe infections in immunosuppressed individuals. C. albicans has hexose transporters that may favor the intracellular accumulation of photosensitizer (PS).

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Effect of Er,Cr:YSGG laser associated with fluoride on the control of enamel erosion progression.

Arch Oral Biol

March 2019

Special Laboratory of Lasers in Dentistry (LELO), Department of Restorative Dentistry, School of Dentistry, University of São Paulo, Av. Prof. Lineu Prestes 2227, São Paulo, SP, 05508-000. Electronic address:

Objective: To evaluate the effect of Er,Cr:YSGG laser associated or not with acidulated phosphate fluoride (APF) on the control of enamel erosion progression.

Design: Enamel slabs (4 mm × 4 mm × 2 mm) from bovine incisors were flattened, polished, and received a tape on their test surfaces, leaving a 4 mm × 1 mm area exposed. Specimens were eroded (10 min in 1% citric acid solution) and randomly assigned into 8 experimental groups (n = 10): Control (no treatment); F (APF gel, 1.

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Background: Carbapenem-resistant bacterial infections are a critical problem in veterinary medicine with limited treatment options.

Objective: To describe effective probiotic and photodynamic therapy of a dog with gut colonization and ear infection caused by a hospital-associated lineage of carbapenemase (VIM-2)-producing Pseudomonas aeruginosa.

Animals: A 5-year-old Lhasa apso dog presented with otitis externa.

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Purpose: To combine advances in high-speed, wide-field optical coherence tomography angiography (OCTA) with image processing methods for semiautomatic quantitative analysis of capillary nonperfusion in patients with diabetic retinopathy (DR).

Methods: Sixty-eight diabetic patients (73 eyes), either without retinopathy or with different degrees of retinopathy, were prospectively recruited for volumetric swept-source OCTA imaging using 12 mm × 12 mm fields centered at the fovea. A custom, semiautomatic software algorithm was used to quantify areas of capillary nonperfusion.

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Evaluation of red light scattering in gingival tissue - in vivo study.

Photodiagnosis Photodyn Ther

September 2018

Department of Biophotonics, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil; School of Dentistry, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. Electronic address:

Antimicrobial photodynamic therapy (aPDT) has been used to treat periodontal disease, thus the aim of this study was to investigate red light (ʎ = 660 nm) attenuation in gingival tissue. This clinical trial included 30 patients with chronic periodontitis; three incisors from each patient were selected for the experimental procedures. A laser source with a radiant power output of 100 mW was used.

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Objective And Background: The correct selections of the cementing agent, the endodontic post material and placement protocol are critical to provide an increased longevity of the teeth that went through endodontic treatment. The irradiation with diode laser before post cementation, can promote an antimicrobial effect. However, there is a lack of information about the effect of 830 nm diode laser on the post bond strength.

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Antiparasitic photodynamic therapy (ApPDT) is an emerging approach to manage cutaneous leishmaniasis (CL) since no side effects, contraindications and parasite resistance have been reported. In addition, methylene blue (MB) is a suitable photosensitizer to mediate ApPDT on CL. In this study we aimed to look for the best parameters to eradicate Leishmania amazonensis and investigated the cell death pathways involved in MB-mediated ApPDT.

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Localized surface plasmon resonance (LSPR) of gold nanoparticles has been reported to increase the antimicrobial effect of the photodynamic therapy. Although silver nanoparticles (AgNPs) are an efficient growth inhibitor of microorganisms, no studies exploring LSPR of AgNPs to enhance the photodynamic inactivation (PDI) have been related. In this work, we described the LSPR phenomenon of AgNP sand investigated its interaction with riboflavin, a natural photosensitizer.

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This in vitro study evaluated the compositional, crystalline, and morphological effects promoted by Nd:YAG laser on root dentin, and verified the effects of laser and topical acidulated phosphate fluoride application (APF-gel) on dentin erosion. 180 bovine dentin slabs were randomized into 4 groups ( = 45): G1-untreated, G2-APF-gel (1.23% F, 4 min), G3-Nd:YAG (1064 nm, 84.

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The aim of this study was to compare the rate of tooth displacement, quantity of root resorption, and alveolar bone changes in five groups: corticopuncture (CP), low-level laser therapy (LLLT), CP combined with LLLT (CP + LLLT), control (C), and negative control (NC). A total of 60 half-maxilla from 30 male Wistar rats (10 weeks old) were divided randomly into five groups: three (CP, LLLT, and CP + LLLT) test groups with different stimulation for accelerated-tooth-movement (ATM), one control (C) group, and one negative control (NC) group with no tooth movement. Nickel-titanium coil springs with 50 g of force were tied from the upper left and right first molars to micro-implants placed behind the maxillary incisors.

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Photodynamic inactivation (PDI) has been reported to be effective to eradicate a wide variety of pathogens, including antimicrobial-resistant microorganisms. The aim of this study was to identify the potential molecular targets of PDI depending on growth phase of Candida albicans. Fungal cells in lag (6h) and stationary (48h) phases were submitted to PDI mediated by methylene blue (MB) combined with a (662±21) nm-LED, at 360mW of optical power.

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Antimicrobial photodynamic therapy for infectious stomatitis in snakes: Clinical views and microbiological findings.

Photodiagnosis Photodyn Ther

December 2017

Department of Internal Medicine, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo/SP, Brazil. Electronic address:

Background: Antimicrobial photodynamic therapy (APDT) has been broadly investigated as an alternative to treat localized infections, without leading to the selection of resistant microorganisms. Infectious stomatitis is a multifactorial disease frequently reported in captive snakes characterized by infection of the oral mucosa and surrounding tissues. In this study, we investigated methylene blue (MB)-mediated APDT to treat infectious stomatitis in snakes and verified the resistance phenotype and genotype before and after APDT.

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Antimicrobial photodynamic therapy on Streptococcus mutans is altered by glucose in the presence of methylene blue and red LED.

Photodiagnosis Photodyn Ther

September 2017

Dep. of Biophotonics, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil; School of Dentistry, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. Electronic address:

Background: Dental caries are a multifactorial disease that progressively produces tooth destruction as a result of bacterial colonization of enamel surface, especially Streptococcus mutans. The objective of this work was to investigate the role of glucose in antimicrobial photodynamic therapy (aPDT) on S. mutans.

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Antimicrobial photodynamic therapy combined to periodontal treatment: Experimental model.

Photodiagnosis Photodyn Ther

June 2017

Dep. of Biophotonics, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil; School of Dentistry, Universidade Nove de Julho (UNINOVE), São Paulo, Brazil. Electronic address:

Background: Antimicrobial photodynamic therapy (aPDT) has been used as an adjuvant treatment for periodontitis. It combines a photosensitizer with a light source to induce reactive oxygen species and kill microbial cells. PpNetNI is a protoporphyrin derivative, and it has a chemical binding site at biofilm and great affinity to microbial cells.

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Purpose: In clinical prosthetics procedures, including endodontics and post fixation, the presence of a smear layer can reduce the post bond strength. An Er,Cr:YSGG laser, which emits at 2780 nm, can promote a smear-layer-free surface due to the ablation process. Considering these aspects, the purpose of this work was to evaluate the influence of Er,Cr:YSGG laser irradiation using either a radial or an axial fiber tip on the bond strength of three resin cements to the fiber-reinforced composite posts.

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