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

This brief report aimed to investigate the optical absorbance spectra of normal, dysplastic, and malignant epithelial cell lines under normal and nutritional stress conditions. HaCAT (keratinocyte), DOK (oral dysplastic), and oral squamous cell carcinoma (OSCC) cell lines (CA1, Luc4, SCC9) were evaluated regarding their optical absorbance after culture with 0-10% fetal bovine serum. Absorbance measurements indicated that HaCAT under serum starvation exhibited higher absorbance at blue (430 nm) and near-infrared (906 nm) wavelengths.

View Article and Find Full Text PDF

Purpose: Triple-negative breast cancer (TNBC) accounts for 20% of all breast cancer cases and is notably resistant to radiotherapy (RT). Photodynamic therapy (PDT) using porphyrins or their derivatives has shown promise as a potential cancer treatment and immune activator. This study evaluated the effects of combining PDT and RT in sublethal conditions for TNBC using in vitro and in vivo models.

View Article and Find Full Text PDF

Introduction: This study aims to evaluate the temperature rise on the external root surface during gutta-percha removal with 2 types of ultrasonic tips, and its relationship with the root dentin thickness.

Methods: A total of 56 single-rooted teeth were prepared for gutta-percha removal procedures, conducted for 40 seconds using 2 types of ultrasonic tips at depths of 6 mm and 11 mm. The temperature generated was measured using a type K thermocouple at 3 measurement points.

View Article and Find Full Text PDF

Introduction: Estimates of the worldwide increase in amputees raises the awareness to solve long-standing problems. Understanding the functional brain modifications after a lower limb amputation (LLA) is one of the first steps towards proposing new rehabilitation approaches. Functional modifications in the central nervous system due the amputation could be involved in prosthesis use failures and Phantom Limb Pain (PLP), increasing costs and overwhelming the health services.

View Article and Find Full Text PDF

Cutaneous leishmaniasis (CL) is a neglected disease caused by Leishmania parasites. The oral drug miltefosine is effective, but there is a growing problem of drug resistance, which has led to increasing treatment failure rates and relapse of infections. Photodynamic therapy (PDT) combines a light source and a photoactive drug to promote cell death by oxidative stress.

View Article and Find Full Text PDF

Evaluation of micronuclei, cytomorphometric and cytologic changes of the oral mucosa in hookah and cigarette smokers.

Oral Surg Oral Med Oral Pathol Oral Radiol

June 2024

Technology Research Center (NPT), Universidade Mogi das Cruzes, Mogi das Cruzes, Brazil; Department of Biosciences and Oral Diagnosis, Institute of Science and Technology, São Paulo State University (Unesp), São José dos Campos, São Paulo, Brazil. Electronic address:

Objective: To analyze the effect of hookah and cigarettes on the oral mucosa of smokers through the use of exfoliative cytology.

Study Design: Smear samples were collected by exfoliative cytology from the tongue of 33 hookah smokers, 22 cigarette smokers, and 30 non-smokers. The selected analyses include micronuclei (MN), metanuclear anomalies, epithelial maturation, and cytomorphology (nuclear area [NA], cytoplasmic area [CA], and NA/CA ratio).

View Article and Find Full Text PDF

The development of novel antimicrobial technologies for the food industry represents an important strategy to improve food safety. Antimicrobial photodynamic disinfection (aPDD) is a method that can inactivate microbes without the use of harsh chemicals. aPDD involves the administration of a non-toxic, light-sensitive substance, known as a photosensitizer, followed by exposure to visible light at a specific wavelength.

View Article and Find Full Text PDF

Recognition of breast cancer subtypes using FTIR hyperspectral data.

Spectrochim Acta A Mol Biomol Spectrosc

April 2024

Center for Lasers and Applications, Instituto de Pesquisas Energeticas e Nucleares, IPEN-CNEN, Address One, Sao Paulo, 05508-000, Sao Paulo, Brazil. Electronic address:

Fourier-transform infrared spectroscopy (FTIR) is a powerful, non-destructive, highly sensitive and a promising analytical technique to provide spectrochemical signatures of biological samples, where markers like carbohydrates, proteins, and phosphate groups of DNA can be recognized in biological micro-environment. However, method of measurements of large cells need an excessive time to achieve high quality images, making its clinical use difficult due to speed of data-acquisition and lack of optimized computational procedures. To address such challenges, Machine Learning (ML) based technologies can assist to assess an accurate prognostication of breast cancer (BC) subtypes with high performance.

View Article and Find Full Text PDF

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient.

View Article and Find Full Text PDF

The emergence of drug resistance in cutaneous leishmaniasis (CL) has become a major problem over the past decades. The spread of resistant phenotypes has been attributed to the wide misuse of current antileishmanial chemotherapy, which is a serious threat to global health. Photodynamic therapy (PDT) has been shown to be effective against a wide spectrum of drug-resistant pathogens.

View Article and Find Full Text PDF

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient.

View Article and Find Full Text PDF

Immunosuppression and critical illnesses in combination with ecological imbalance open the door for novel opportunistic fungal infections, as in case of . has emerged globally as a multidrug-resistant yeast, causing infections and outbreaks in health care facilities. This narrative review discusses the properties of the yeast, the development of the epidemiological situation, the nosocomial spread and causes for nosocomial outbreaks triggered by in the hospital environment, and summarizes international recommendations for infection control, supplemented by suggestions on diagnostic, screening and antibiotic stewardship.

View Article and Find Full Text PDF

The unbridled use of antimicrobial drugs over the last decades contributed to the global dissemination of drug-resistant pathogens and increasing rates of life-threatening infections for which limited therapeutic options are available. Currently, the search for safe, fast, and effective therapeutic strategies to combat infectious diseases is a worldwide demand. Antimicrobial photodynamic therapy (APDT) rises as a promising therapeutic approach against a wide range of pathogenic microorganisms.

View Article and Find Full Text PDF

Melanoma is a serious and aggressive type of skin cancer with growing incidence, and it is the leading cause of death among those affected by this disease. Although surgical resection has been employed as a first-line treatment for the early stages of the tumor, noninvasive topical treatments might represent an alternative option. However, they can be irritating to the skin and result in undesirable side effects.

View Article and Find Full Text PDF

In recent years, has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against .

View Article and Find Full Text PDF

New Insights into the Bacterial Targets of Antimicrobial Blue Light.

Microbiol Spectr

February 2023

Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil.

Antimicrobial blue light (aBL) offers efficacy and safety in treating infections. However, the bacterial targets for aBL are still poorly understood and may be dependent on bacterial species. Here, we investigated the biological targets of bacterial killing by aBL (λ = 410 nm) on three pathogens: Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.

View Article and Find Full Text PDF

Methylene blue-mediated antimicrobial photodynamic therapy on chicken semen.

Photodiagnosis Photodyn Ther

March 2023

Department of Animal Reproduction, College of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Av. Prof. Dr. Orlando Marques de Paiva, 87, CEP, SP 05508-900, Brazil. Electronic address:

Background: Artificial insemination is widely employed in poultry, but high degrees of bacterial contamination are often observed in semen because of its passage through the cloaca. Consequently, most semen extenders for birds have antibiotics that could aggravate bacterial resistance.

Methods: We evaluated the potential of antimicrobial photodynamic therapy (PDT) as an alternative to the use of antibiotics, and assessed whether changes in concentration and incubation time with methylene blue (MB), radiant exposure, and irradiance of light affect spermatozoa activity and bacteria in chicken semen.

View Article and Find Full Text PDF

Monitoring glucose levels in urine using FTIR spectroscopy combined with univariate and multivariate statistical methods.

Spectrochim Acta A Mol Biomol Spectrosc

April 2023

Innovation Center in Salivary Diagnostics and Nanobiotechnology, Department of Physiology, Institute of Biomedical Sciences, Federal University of Uberlandia, Uberlandia, Brazil. Electronic address:

The development of novel platforms for non-invasive continuous glucose monitoring applied in the screening and monitoring of diabetes is crucial to improve diabetes surveillance systems. Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy of urine can be an alternative as a sustainable, label-free, fast, non-invasive, and highly sensitive analysis to detect changes in urine promoted by diabetes and insulin treatment. In this study, we used ATR-FTIR to evaluate the urinary components of non-diabetic (ND), diabetic (D), and diabetic insulin-treated (D + I) rats.

View Article and Find Full Text PDF

The mechanisms of action of photobiomodulation (PBM) in oral mucositis (OM) are not completely elucidated. To enlighten the role of PBM in the evolution of epithelial maturity in OM ulcers, the present study evaluated the effect of PBM with red (λ) wavelength of 660 nanometers (nm) and infrared of 780 nm in radio-induced OM wounds on the tongue of rats, eight and twenty days after irradiation with single dose of 20 Gy. The percentage area corresponding to positive staining for cytokeratin 10 (CK10) and 14 (CK14) proteins was evaluated in the epithelial area of the lesions, using an immunohistochemical technique (IHC), 8 and 20 days after the induction of lesions, and compared with an untreated control group.

View Article and Find Full Text PDF

Selecting High-Performance Gold Nanorods for Photothermal Conversion.

Nanomaterials (Basel)

November 2022

Laboratory of Biomedical Optics and Imaging, Federal University of Pernambuco, Recife 50740-540, Brazil.

In this work, we establish a new paradigm on identifying optimal arbitrarily shaped metallic nanostructures for photothermal applications. Crucial thermo-optical parameters that rule plasmonic heating are appraised, exploring a nanoparticle size-dependence approach. Our results indicate two distinct figures of merit for the optimization of metallic nanoheaters, under both non-cumulative femtosecond and continuum laser excitation.

View Article and Find Full Text PDF

Sporotrichosis is a mycotic infection of humans and animals caused by different fungal species of the genus Sporothrix. Feline sporotrichosis presents a broad spectrum of clinical manifestations and its treatment with classic antifungal drugs is often long and frustrating. Methylene blue-mediated antimicrobial photodynamic therapy (MB-APDT) comes to light as an interesting approach against fungal infections, including sporotrichosis.

View Article and Find Full Text PDF

Regulation of inflammation is a critical process for maintaining physiological homeostasis. The λ-carrageenan (λ-CGN) is a mucopolysaccharide extracted from the cell wall of red algae () capable of inducing acute intestinal inflammation, which is translated into the production of acute phase reactants secreted into the blood circulation. However, the associated mechanisms in vertebrates are not well understood.

View Article and Find Full Text PDF

Thermal damage and excision time of micro and super pulsed diode lasers: A comparative ex vivo analysis.

Clin Exp Dent Res

December 2022

Department of Restorative Dentistry & Prosthodontics, University of Texas Health Science Center at Houston, School of Dentistry, Houston, Texas, USA.

Objectives: The primary aim of this ex vivo study was to evaluate thermal damage and cutting efficiency of micro and super pulsed diode lasers. The secondary aim was to suggest a guideline to perform simple surgical excisions adequate for histopathological evaluation.

Material And Methods: Ten groups of 10 specimens of pig tongues were excised using a blade (G1), a micro pulsed (G2-G9), and a super pulsed diode (G10) lasers.

View Article and Find Full Text PDF

Melanoma is a highly aggressive skin cancer that requires new approaches for its management. Low-level laser therapy, currently named photobiomodulation therapy (PBM), has been used to improve different conditions but its effects and safe use on melanoma remain unexplored. Herein, we investigated the PBM impact on melanoma cells differing by pigmentation using near-infrared (NIR) and red lasers in vitro.

View Article and Find Full Text PDF