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Gonçalves IS, Lima LR, Berretta AA, Amorim NA, Pratavieira S, Corrêa TQ, Nogueira FAR, Barud HS. Antimicrobial Formulation of a Bacterial Nanocellulose/Propolis-Containing Photosensitizer for Biomedical Applications. Polymers (Basel) 2023; 15:polym15040987. [PMID: 36850271 PMCID: PMC9968145 DOI: 10.3390/polym15040987] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 02/13/2023] [Accepted: 02/14/2023] [Indexed: 02/18/2023] Open
Abstract
With the aim of contributing to the development of more efficient materials for wound care, new topical formulations based on bacterial nanocellulose (BNC) hydrogels containing propolis were produced. Characterizations confirmed the incorporation of propolis into the BNC matrix, maintaining its structure and properties. Rheological analysis confirmed that the hydrogels showed thixotropic behavior appropriate for topical application. Chromatographic profiles showed sustained release of propolis biomarkers for at least 20 h. The formulations did not present mutagenicity. For application in photodynamic inactivation (PDI), BNC/propolis hydrogels were prepared with the photosensitizers methylene blue (MB). Spectroscopy and confocal fluorescence microscopy confirmed the interaction of MB and propolis in BNC hydrogels, as well as the formation of a new composite material. In the antibacterial assays, formulations containing MB and propolis significantly reduced Staphylococcus aureus growth. In the presence of light, BNC/MB hydrogels completely inhibited the microorganism. Therefore, the results suggest potential materials for the prevention or treatment of Staphylococcus aureus infections in wounds.
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Affiliation(s)
- Isabella Salgado Gonçalves
- Laboratório de Biopolímeros e Biomateriais—BioPolMat, University of Araraquara, Araraquara 14801-320, SP, Brazil
- Exact Sciences and Technology Center, Federal University of São Carlos, São Carlos 13565-905, SP, Brazil
- Physics Institute of São Carlos, University of São Paulo, São Carlos 05508-060, SP, Brazil
| | - Lais Roncalho Lima
- Chemistry Department, Federal University of São Carlos, São Carlos 13565-905, SP, Brazil
- Chemistry Department, Federal University of Maranhão, São Luís 65080-805, MA, Brazil
- Correspondence: (L.R.L.); (H.S.B.); Tel.: +55-(16)-988-144-338 (L.R.L.); +55-(16)-981-233-935 (H.S.B.)
| | - Andresa Aparecida Berretta
- Research, Development and Innovation Department, Apis Flora Indl. Coml. Ribeirão, Preto 14020-670, SP, Brazil
| | - Nathaly Alcazar Amorim
- Research, Development and Innovation Department, Apis Flora Indl. Coml. Ribeirão, Preto 14020-670, SP, Brazil
| | - Sebastião Pratavieira
- Physics Institute of São Carlos, University of São Paulo, São Carlos 05508-060, SP, Brazil
| | - Thaila Quatrini Corrêa
- Physics Institute of São Carlos, University of São Paulo, São Carlos 05508-060, SP, Brazil
| | | | - Hernane Silva Barud
- Laboratório de Biopolímeros e Biomateriais—BioPolMat, University of Araraquara, Araraquara 14801-320, SP, Brazil
- Correspondence: (L.R.L.); (H.S.B.); Tel.: +55-(16)-988-144-338 (L.R.L.); +55-(16)-981-233-935 (H.S.B.)
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Insights into Biochemical Sources and Diffuse Reflectance Spectral Features for Colorectal Cancer Detection and Localization. Cancers (Basel) 2022; 14:cancers14225715. [PMID: 36428806 PMCID: PMC9688116 DOI: 10.3390/cancers14225715] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/07/2022] [Accepted: 11/09/2022] [Indexed: 11/23/2022] Open
Abstract
Colorectal cancer (CRC) is the third most common and second most deadly type of cancer worldwide. Early detection not only reduces mortality but also improves patient prognosis by allowing the use of minimally invasive techniques to remove cancer while avoiding major surgery. Expanding the use of microsurgical techniques requires accurate diagnosis and delineation of the tumor margins in order to allow complete excision of cancer. We have used diffuse reflectance spectroscopy (DRS) to identify the main optical CRC biomarkers and to optimize parameters for the integration of such technologies into medical devices. A total number of 2889 diffuse reflectance spectra were collected in ex vivo specimens from 47 patients. Short source-detector distance (SDD) and long-SDD fiber-optic probes were employed to measure tissue layers from 0.5 to 1 mm and from 0.5 to 1.9 mm deep, respectively. The most important biomolecules contributing to differentiating DRS between tissue types were oxy- and deoxy-hemoglobin (Hb and HbO2), followed by water and lipid. Accurate tissue classification and potential DRS device miniaturization using Hb, HbO2, lipid and water data were achieved particularly well within the wavelength ranges 350-590 nm and 600-1230 nm for the short-SDD probe, and 380-400 nm, 420-610 nm, and 650-950 nm for the long-SDD probe.
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Leal LB, Nogueira MS, Mageski JGA, Martini TP, Barauna VG, Dos Santos L, de Carvalho LFDCES. Diagnosis of Systemic Diseases Using Infrared Spectroscopy: Detection of Iron Overload in Plasma-Preliminary Study. Biol Trace Elem Res 2021; 199:3737-3751. [PMID: 33415581 DOI: 10.1007/s12011-020-02510-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 11/23/2020] [Indexed: 02/07/2023]
Abstract
Despite the important role of iron in cellular homeostasis, iron overload (IO) is associated with systemic and tissue deposits which damage several organs. In order to reduce the impact caused by IO, invasive diagnosis exams (e.g., biopsies) and minimally invasive methods were developed including computed tomography and magnetic resonance imaging. However, current diagnostic methods are still time-consuming and expensive. A cost-effective solution is using Fourier-transform infrared spectroscopy (FTIR) for real-time and molecular-sensitive biofluid analysis during conventional laboratory exams. In this study, we performed the first evaluation of the accuracy of FTIR for IO diagnosis. The study was performed by collecting FTIR spectra of plasma samples of five rats intravenously injected with iron-dextran and five control rats. We developed a classification model based on principal component analysis and supervised methods including J48, random forest, multilayer perceptron, and radial basis function network. We achieved 100% accuracy for the classification of the IO status and provided a list of possible biomolecules related to the vibrational modes detected. In this preliminary study, we give a first step towards real-time diagnosis for acute IO or intoxication. Furthermore, we have expanded the literature knowledge regarding the pathophysiological changes induced by iron overload.
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Affiliation(s)
- Leonardo Barbosa Leal
- Department of Physiological Sciences, Federal University of Espírito Santo (UFES), Marechal Campos Ave, 1468, Maruípe, Vitória, Espírito Santo, 29040-090, Brazil.
| | - Marcelo Saito Nogueira
- Tyndall National Institute/University College Cork - Lee Maltings Complex, Dyke Parade, Cork, T12R5CP, Ireland
| | - Jandinay Gonzaga Alexandre Mageski
- Department of Physiological Sciences, Federal University of Espírito Santo (UFES), Marechal Campos Ave, 1468, Maruípe, Vitória, Espírito Santo, 29040-090, Brazil
| | - Thiago Pereira Martini
- Institute of Science and Technology, Federal University of Sao Paulo, São José dos Campos, Brazil
| | - Valério Garrone Barauna
- Department of Physiological Sciences, Federal University of Espírito Santo (UFES), Marechal Campos Ave, 1468, Maruípe, Vitória, Espírito Santo, 29040-090, Brazil
| | - Leonardo Dos Santos
- Department of Physiological Sciences, Federal University of Espírito Santo (UFES), Marechal Campos Ave, 1468, Maruípe, Vitória, Espírito Santo, 29040-090, Brazil
| | - Luis Felipe das Chagas E Silva de Carvalho
- Universidade de Taubaté. R. dos Operários, 09 - Centro, Taubaté, São Paulo, 12020-340, Brazil
- Centro Universitário Braz Cubas, Av. Francisco Rodrigues Filho, 1233 - Vila Mogilar, Mogi das Cruzes, São Paulo, Brazil
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Methods of Non-Invasive In Vivo Optical Diagnostics in the Assessment of Structural Changes in the Skin Induced by Ultraviolet Exposure in an Experimental Model. Diagnostics (Basel) 2021; 11:diagnostics11081464. [PMID: 34441398 PMCID: PMC8394888 DOI: 10.3390/diagnostics11081464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2021] [Revised: 08/05/2021] [Accepted: 08/10/2021] [Indexed: 11/23/2022] Open
Abstract
Background: This paper demonstrates the use of optical diagnostic methods to assess the dynamic skin changes observed in acute and chronic exposure to ultraviolet (UV) radiation in vivo. Methods: Firstly, in order to initiate photoaging (chronic UV exposure), animals (n = 40) were divided into two groups: chronic UV exposure (n = 30), and control (n = 10; without irradiation). Photoaging in animals was induced by chronic repeated exposure to UVA radiation three times per week, for 12 weeks continuously, while the UV dose increased stepwise over the course of the experiment (55 minimal erythema doses (MED) in total). Laser fluorescence spectroscopy (LFS), optical tissue oximetry (OTO), laser Doppler flowmetry (LDF), and optical coherence tomography (OCT) of the shaved dorsum skin were performed regularly, once per week until the conclusion of the study. At 0, 5, and 12 weeks of the experiment, histological examination of animal tissues using hematoxylin/eosin and Masson’s trichrome staining was performed. At the second stage, erythema was induced in mice (n = 15) by acute UV exposure at high doses. The colorimetric assay of the image from a digital RGB camera was used to evaluate the erythema index. Results: The tissue content index ηcollagen of collagen was appropriate for the characterization of skin photoaging. Significant differences (p < 0.05) in ηcollagen were found between the control and photoaging groups from the 5th to the 9th week of the experiment. In addition, the rate of collagen degradation in the control group was about half that of the photoaging group. This marker allows the differentiation of photo- and chronoaging. OCT revealed the main optical layers of the skin in compliance with the histological pattern. The analysis of the RGB camera images provided visualization of the acute skin reaction to UV radiation. Conclusions: This study demonstrates the applicability of optical methods for the quantitative assessment of acute and chronic skin effects of UV exposure in vivo.
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Ponce Ayala ET, Alves Dias de Sousa F, Vollet-Filho JD, Rodrigues Garcia M, de Boni L, Salvador Bagnato V, Pratavieira S. Photodynamic and Sonodynamic Therapy with Protoporphyrin IX: In Vitro and In Vivo Studies. ULTRASOUND IN MEDICINE & BIOLOGY 2021; 47:1032-1044. [PMID: 33446374 DOI: 10.1016/j.ultrasmedbio.2020.12.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 12/04/2020] [Accepted: 12/10/2020] [Indexed: 05/25/2023]
Abstract
Sono-photodynamic therapy is a promising anticancer technique based on the combination of sonodynamic and photodynamic therapy to improve the cancer treatment effectiveness. This study was aimed at analyzing the effects of the sono-photodynamic (SPD) activity on protoporphyrin IX (PpIX) solution and PpIX-loaded rat liver. In vitro, PpIX 5 μM solutions were irradiated with light (635 nm, 30-50 mW/cm2), ultrasound (1 MHz, 1-2 W/cm2) and both. The PpIX absorption spectra recorded over exposure time revealed that the PpIX decay rate induced by SPD activity (combined irradiation) was approximately the sum of those induced by photodynamic and sonodynamic activity. In vivo, rats were intraperitoneally injected with 5-aminolevulinic acid at the dose of 500 mg/kg weight. After 3 h of injection, the PpIX-loaded livers were irradiated with light (635 nm, 180 ± 9 J/cm2), ultrasound (1.0 MHz, 770 ± 40 J/cm2) and both using a single probe capable of illuminating and sonicating the liver simultaneously. After 30 h, the liver damage induced by each protocol was analyzed histologically. It was found that a greater necrosis depth was induced by the SPD activity. These results suggest that the SPD activity could improve the PpIX decay rate and have greater scope than photodynamic or sonodynamic activity. Further studies should be performed to gain a better understanding of this protocol.
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Affiliation(s)
| | | | | | | | - Leonardo de Boni
- São Carlos Institute of Physics, University of São Paulo, São Carlos, São Paulo, Brazil
| | | | - Sebastião Pratavieira
- São Carlos Institute of Physics, University of São Paulo, São Carlos, São Paulo, Brazil
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Nogueira MS, Brugnera Junior A, Bagnato VS, Panhóca VH. Evaluation of the Whitening Effectiveness of Violet Illumination Alone or Combined with Hydrogen Peroxide Gel. Photobiomodul Photomed Laser Surg 2021; 39:395-402. [PMID: 33439765 DOI: 10.1089/photob.2020.4846] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Objective: To evaluate the effectiveness of the whitening and washing steps of a treatment using violet illumination (VI) alone or combined with hydrogen peroxide gel. In addition, we evaluated the color change after cleaning the tooth with and without mineral oil. Methods: First, 16 bovine teeth were extracted and stored in 5% thymol solution. Next, the teeth were collected and cleaned. Then, the teeth were stained with instant coffee solution for 24 h. The teeth were divided in four groups: control, VI without 35% hydrogen peroxide gel (VI), VI with 35% hydrogen peroxide gel (VI + gel), and VI without 35% hydrogen peroxide gel and cleaned with mineral oil before washing (VI + oil). Results: The whitening treatment VI + gel was able to completely restore the teeth whiteness and make the teeth 31.2% less yellow than prior coffee staining. The VI + oil treatment led to about 3.7 times the whiteness and yellowness changes observed in the VI treatment and restored 51% of the whiteness lost by staining. Conclusions: The VI + gel treatment can be recommended against coffee stains and should be further investigated for other types of tooth stains. In addition, cleaning the tooth surface with mineral oil could be an alternative to increase the performance of whitening treatments.
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Affiliation(s)
| | - Aldo Brugnera Junior
- Physics Institute of São Carlos, University of Sao Paulo, São Carlos, Brazil.,Department of Dental Science, Faculty of Medicine, Emdola, University in Liège, Liège, Belgium
| | | | - Vitor Hugo Panhóca
- São Carlos Institute of Physics, University of São Paulo, São Carlos, Brazil
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Nogueira MS, Maryam S, Amissah M, Lu H, Lynch N, Killeen S, O’Riordain M, Andersson-Engels S. Evaluation of wavelength ranges and tissue depth probed by diffuse reflectance spectroscopy for colorectal cancer detection. Sci Rep 2021; 11:798. [PMID: 33436684 PMCID: PMC7804163 DOI: 10.1038/s41598-020-79517-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 12/04/2020] [Indexed: 01/29/2023] Open
Abstract
Colorectal cancer (CRC) is the third most common type of cancer worldwide and the second most deadly. Recent research efforts have focused on developing non-invasive techniques for CRC detection. In this study, we evaluated the diagnostic capabilities of diffuse reflectance spectroscopy (DRS) for CRC detection by building 6 classification models based on support vector machines (SVMs). Our dataset consists of 2889 diffuse reflectance spectra collected from freshly excised ex vivo tissues of 47 patients over wavelengths ranging from 350 and 1919 nm with source-detector distances of 630-µm and 2500-µm to probe different depths. Quadratic SVMs were used and performance was evaluated using twofold cross-validation on 10 iterations of randomized training and test sets. We achieved (93.5 ± 2.4)% sensitivity, (94.0 ± 1.7)% specificity AUC by probing the superficial colorectal tissue and (96.1 ± 1.8)% sensitivity, (95.7 ± 0.6)% specificity AUC by sampling deeper tissue layers. To the best of our knowledge, this is the first DRS study to investigate the potential of probing deeper tissue layers using larger SDD probes for CRC detection in the luminal wall. The data analysis showed that using a broader spectrum and longer near-infrared wavelengths can improve the diagnostic accuracy of CRC as well as probing deeper tissue layers.
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Affiliation(s)
- Marcelo Saito Nogueira
- grid.7872.a0000000123318773Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland ,grid.7872.a0000000123318773Department of Physics, University College Cork, College Road, Cork, Ireland
| | - Siddra Maryam
- grid.7872.a0000000123318773Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland ,grid.7872.a0000000123318773Department of Physics, University College Cork, College Road, Cork, Ireland
| | - Michael Amissah
- grid.7872.a0000000123318773Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland ,grid.7872.a0000000123318773Department of Physics, University College Cork, College Road, Cork, Ireland
| | - Huihui Lu
- grid.7872.a0000000123318773Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland
| | - Noel Lynch
- grid.411785.e0000 0004 0575 9497Department of Surgery, Mercy University Hospital, Cork, Ireland
| | - Shane Killeen
- grid.411785.e0000 0004 0575 9497Department of Surgery, Mercy University Hospital, Cork, Ireland
| | - Micheal O’Riordain
- grid.411785.e0000 0004 0575 9497Department of Surgery, Mercy University Hospital, Cork, Ireland
| | - Stefan Andersson-Engels
- grid.7872.a0000000123318773Tyndall National Institute, Lee Maltings, Dyke Parade, Cork, Ireland ,grid.7872.a0000000123318773Department of Physics, University College Cork, College Road, Cork, Ireland
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In vivo Raman spectroscopic characteristics of different sites of the oral mucosa in healthy volunteers. Clin Oral Investig 2018; 23:3021-3031. [DOI: 10.1007/s00784-018-2714-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 10/17/2018] [Indexed: 02/07/2023]
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Narayanamurthy V, Padmapriya P, Noorasafrin A, Pooja B, Hema K, Firus Khan AY, Nithyakalyani K, Samsuri F. Skin cancer detection using non-invasive techniques. RSC Adv 2018; 8:28095-28130. [PMID: 35542700 PMCID: PMC9084287 DOI: 10.1039/c8ra04164d] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 07/22/2018] [Indexed: 12/22/2022] Open
Abstract
Skin cancer is the most common form of cancer and is globally rising. Historically, the diagnosis of skin cancers has depended on various conventional techniques which are of an invasive manner. A variety of commercial diagnostic tools and auxiliary techniques are available to detect skin cancer. This article explains in detail the principles and approaches involved for non-invasive skin cancer diagnostic methods such as photography, dermoscopy, sonography, confocal microscopy, Raman spectroscopy, fluorescence spectroscopy, terahertz spectroscopy, optical coherence tomography, the multispectral imaging technique, thermography, electrical bio-impedance, tape stripping and computer-aided analysis. The characteristics of an ideal screening test are outlined, and the authors pose several points for clinicians and scientists to consider in the evaluation of current and future studies of skin cancer detection and diagnosis. This comprehensive review critically analyses the literature associated with the field and summarises the recent updates along with their merits and demerits.
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Affiliation(s)
- Vigneswaran Narayanamurthy
- InnoFuTech No: 42/12, 7th Street, Vallalar Nagar, Pattabiram Chennai Tamil Nadu 600072 India
- Faculty of Electrical and Electronics Engineering, University Malaysia Pahang Pekan 26600 Malaysia
| | - P Padmapriya
- Department of Biomedical Engineering, Veltech Multitech Dr. RR & Dr. SR Engineering College Chennai 600 062 India
| | - A Noorasafrin
- Department of Biomedical Engineering, Veltech Multitech Dr. RR & Dr. SR Engineering College Chennai 600 062 India
| | - B Pooja
- Department of Biomedical Engineering, Veltech Multitech Dr. RR & Dr. SR Engineering College Chennai 600 062 India
| | - K Hema
- Department of Biomedical Engineering, Veltech Multitech Dr. RR & Dr. SR Engineering College Chennai 600 062 India
| | - Al'aina Yuhainis Firus Khan
- Department of Biomedical Science, Faculty of Allied Health Sciences, International Islamic University Malaysia 25200 Kuantan Pahang Malaysia
| | - K Nithyakalyani
- Department of Biomedical Engineering, Veltech Multitech Dr. RR & Dr. SR Engineering College Chennai 600 062 India
| | - Fahmi Samsuri
- Faculty of Electrical and Electronics Engineering, University Malaysia Pahang Pekan 26600 Malaysia
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Sarkar R, Chatterjee K, Ojha D, Chakraborty B, Sengupta S, Chattopadhyay D, RoyChaudhuri C, Barui A. Liaison between heme metabolism and bioenergetics pathways-a multimodal elucidation for early diagnosis of oral cancer. Photodiagnosis Photodyn Ther 2018; 21:263-274. [DOI: 10.1016/j.pdpdt.2018.01.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Revised: 12/29/2017] [Accepted: 01/03/2018] [Indexed: 10/18/2022]
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de Carvalho LFDCES, Saito Nogueira M. New insights of Raman spectroscopy for oral clinical applications. Analyst 2018; 143:6037-6048. [DOI: 10.1039/c8an01363b] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Oral injuries are currently diagnosed by histopathological analysis of biopsy, which is an invasive procedure and does not give immediate results.
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Saito Nogueira M, Cosci A, Teixeira Rosa RG, Salvio AG, Pratavieira S, Kurachi C. Portable fluorescence lifetime spectroscopy system for in-situ interrogation of biological tissues. JOURNAL OF BIOMEDICAL OPTICS 2017; 22:1-10. [PMID: 29052374 DOI: 10.1117/1.jbo.22.12.121608] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/22/2017] [Indexed: 06/07/2023]
Abstract
Fluorescence spectroscopy and lifetime techniques are potential methods for optical diagnosis and characterization of biological tissues with an in-situ, fast, and noninvasive interrogation. Several diseases may be diagnosed due to differences in the fluorescence spectra of targeted fluorophores, when, these spectra are similar, considering steady-state fluorescence, others may be detected by monitoring their fluorescence lifetime. Despite this complementarity, most of the current fluorescence lifetime systems are not robust and portable, and not being feasible for clinical applications. We describe the assembly of a fluorescence lifetime spectroscopy system in a suitcase, its characterization, and validation with clinical measurements of skin lesions. The assembled system is all encased and robust, maintaining its mechanical, electrical, and optical stability during transportation, and is feasible for clinical measurements. The instrument response function measured was about 300 ps, and the system is properly calibrated. At the clinical study, the system showed to be reliable, and the achieved spectroscopy results support its potential use as an auxiliary tool for skin diagnostics.
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Affiliation(s)
| | - Alessandro Cosci
- University of São Paulo, São Carlos Institute of Physics, São Carlos, São Paulo, Brazil
| | | | | | - Sebastião Pratavieira
- University of São Paulo, São Carlos Institute of Physics, São Carlos, São Paulo, Brazil
| | - Cristina Kurachi
- University of São Paulo, São Carlos Institute of Physics, São Carlos, São Paulo, Brazil
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