Patrícia Silva Barbosa, A. Freitas, G. R. D. Sant´Anna
The aim of this study was to assess the effect in the enamel demineralization of low-intensity infrared laser (λ=810 nm, 100 mW/cm2, 90 sec, 4.47 J/cm2, 9 J) with or without photodynamic cream fluorinated or not fluorinated, using Optical Coherence Tomography (OCT). Background data: Lasers can be used as tools for the prevention of tooth enamel demineralization. All enamel specimens (n= 105) were analyzed using OCT at baseline, and randomly assigned into seven groups (n=15): C (+), laser application; C(-), no treatment; (F), acid fluoride gel; cream (IV); cream and neutral fluoride (IVF); cream and laser (IVL); and cream with neutral fluoride+ laser (IVFL). The specimens were submitted to all kind of treatments before demineralizing pH cycling challenge and were reanalyzed. ANOVA and Tukey's multiple comparative analysis (p <0.01) demonstrated a greater delta attenuation between baseline and post challenge for C + (0.034 ± 0.011) compared to IVF (0.016 ± 0.007) F (0.018 ± 0.010) IVFL (0.019 ± 0.008), and IVL (0.014 ± 0.010). The cream laser group (IVL) also showed lower delta (0.014 ± 0.010) compared to C - (0.025 ± 0.008). The OCT technique demonstrated that cream associated with laser showed the lowest quantitative enamel mineral looses after cariogenic challenge.
{"title":"Analysis of photodynamic cream effect in dental caries using optical coherence tomography","authors":"Patrícia Silva Barbosa, A. Freitas, G. R. D. Sant´Anna","doi":"10.1117/12.2180962","DOIUrl":"https://doi.org/10.1117/12.2180962","url":null,"abstract":"The aim of this study was to assess the effect in the enamel demineralization of low-intensity infrared laser (λ=810 nm, 100 mW/cm2, 90 sec, 4.47 J/cm2, 9 J) with or without photodynamic cream fluorinated or not fluorinated, using Optical Coherence Tomography (OCT). Background data: Lasers can be used as tools for the prevention of tooth enamel demineralization. All enamel specimens (n= 105) were analyzed using OCT at baseline, and randomly assigned into seven groups (n=15): C (+), laser application; C(-), no treatment; (F), acid fluoride gel; cream (IV); cream and neutral fluoride (IVF); cream and laser (IVL); and cream with neutral fluoride+ laser (IVFL). The specimens were submitted to all kind of treatments before demineralizing pH cycling challenge and were reanalyzed. ANOVA and Tukey's multiple comparative analysis (p <0.01) demonstrated a greater delta attenuation between baseline and post challenge for C + (0.034 ± 0.011) compared to IVF (0.016 ± 0.007) F (0.018 ± 0.010) IVFL (0.019 ± 0.008), and IVL (0.014 ± 0.010). The cream laser group (IVL) also showed lower delta (0.014 ± 0.010) compared to C - (0.025 ± 0.008). The OCT technique demonstrated that cream associated with laser showed the lowest quantitative enamel mineral looses after cariogenic challenge.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115794154","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
N. Prindeze, H. Hoffman, B. Carney, L. Moffatt, M. Loew, J. Shupp
Active dynamic thermography (ADT) is an imaging technique capable of characterizing the non-homogenous thermal conductance of damaged tissues. The purpose of this study was to determine optimal stimulation parameters and quantify the optical resolution of ADT through various depths of human skin. Excised tissue from plastic surgery operations was collected immediately following excision. A total of 12 thin to thick split-thickness grafts were harvested from 3 patients. Grafts were placed on top of a 3D printed resolution chart and thermal stimulation was applied from a 300W halogen lamp array for between 0.5-10 seconds to determine optimal parameters. Video was captured with a thermal camera, and analysis was performed by reconstructing an image from thermal gradients. In this study ADT resolved 0.445±0 lp/mm at a depth of 0.010”, 0.356±0.048 lp/mm at a depth of 0.015”, 0.334±0.027 lp/mm at a depth of 0.020” and 0.265±0.022 lp/mm at a depth of 0.025”. The stimulus energy required for maximum resolution at each depth was 3- 4s, 8s, 12s and 12s respectively. ADT is a sensitive technique for imaging dermal structure, capable of resolving detail as fine as 1124 μm, 1427 μm, 1502 μm and 1893 μm in thin to thick split-thickness skin grafts respectively. This study has characterized a correlation between stimulus input and maximal resolution at differing depths of skin. It has also defined the functional imaging depth of ADT to below the sub-cutis, well below conventional spectrophotometric techniques.
{"title":"Evaluation of the variable depth resolution of active dynamic thermography on human skin","authors":"N. Prindeze, H. Hoffman, B. Carney, L. Moffatt, M. Loew, J. Shupp","doi":"10.1117/12.2180807","DOIUrl":"https://doi.org/10.1117/12.2180807","url":null,"abstract":"Active dynamic thermography (ADT) is an imaging technique capable of characterizing the non-homogenous thermal conductance of damaged tissues. The purpose of this study was to determine optimal stimulation parameters and quantify the optical resolution of ADT through various depths of human skin. Excised tissue from plastic surgery operations was collected immediately following excision. A total of 12 thin to thick split-thickness grafts were harvested from 3 patients. Grafts were placed on top of a 3D printed resolution chart and thermal stimulation was applied from a 300W halogen lamp array for between 0.5-10 seconds to determine optimal parameters. Video was captured with a thermal camera, and analysis was performed by reconstructing an image from thermal gradients. In this study ADT resolved 0.445±0 lp/mm at a depth of 0.010”, 0.356±0.048 lp/mm at a depth of 0.015”, 0.334±0.027 lp/mm at a depth of 0.020” and 0.265±0.022 lp/mm at a depth of 0.025”. The stimulus energy required for maximum resolution at each depth was 3- 4s, 8s, 12s and 12s respectively. ADT is a sensitive technique for imaging dermal structure, capable of resolving detail as fine as 1124 μm, 1427 μm, 1502 μm and 1893 μm in thin to thick split-thickness skin grafts respectively. This study has characterized a correlation between stimulus input and maximal resolution at differing depths of skin. It has also defined the functional imaging depth of ADT to below the sub-cutis, well below conventional spectrophotometric techniques.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129842334","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In laser cut clinical applications, the use of energy densities lower than the ablation threshold causes increase of temperature of the irradiated tissue, which might result in an irreversible thermal damage. Hence, knowing the ablation threshold is crucial for insuring the safety of these procedures. The aim of this study was to determine the ablation threshold of the Er,Cr:YSGG laser in bone tissue. Bone pieces from jaws of New Zealand rabbits were cut as blocks of 5 mm × 8 mm and polished with sandpaper. The Er,Cr:YSGG laser used in this study had wavelength of 2780 nm, 20 Hz of frequency, and the irradiation condition was chosen so as to simulate the irradiation during a surgical procedure. The laser irradiation was performed with 12 different values of laser energy densities, between 3 J/cm2 and 42 J/cm2, during 3 seconds, resulting in the overlap of 60 pulses. This process was repeated in each sample, for all laser energy densities. After irradiation, the samples were analyzed by scanning electron microscope (SEM), and it was measured the crater diameter for each energy density. By fitting a curve that related the ablation threshold with the energy density and the corresponding diameter of ablation crater, it was possible to determine the ablation threshold. The results showed that the ablation threshold of the Er,Cr:YSGG in bone tissue was 1.95±0.42 J/cm2.
{"title":"The ablation threshold of Er;Cr:YSGG laser radiation in bone tissue","authors":"C. Benetti, D. Zezell","doi":"10.1117/12.2180712","DOIUrl":"https://doi.org/10.1117/12.2180712","url":null,"abstract":"In laser cut clinical applications, the use of energy densities lower than the ablation threshold causes increase of temperature of the irradiated tissue, which might result in an irreversible thermal damage. Hence, knowing the ablation threshold is crucial for insuring the safety of these procedures. The aim of this study was to determine the ablation threshold of the Er,Cr:YSGG laser in bone tissue. Bone pieces from jaws of New Zealand rabbits were cut as blocks of 5 mm × 8 mm and polished with sandpaper. The Er,Cr:YSGG laser used in this study had wavelength of 2780 nm, 20 Hz of frequency, and the irradiation condition was chosen so as to simulate the irradiation during a surgical procedure. The laser irradiation was performed with 12 different values of laser energy densities, between 3 J/cm2 and 42 J/cm2, during 3 seconds, resulting in the overlap of 60 pulses. This process was repeated in each sample, for all laser energy densities. After irradiation, the samples were analyzed by scanning electron microscope (SEM), and it was measured the crater diameter for each energy density. By fitting a curve that related the ablation threshold with the energy density and the corresponding diameter of ablation crater, it was possible to determine the ablation threshold. The results showed that the ablation threshold of the Er,Cr:YSGG in bone tissue was 1.95±0.42 J/cm2.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132627193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Granular phosphors are commonly used in several applications in biomedical imaging and instrumentation. The structural and optical properties of phosphor materials affect the optical signal transferred out and play a critical role in the quality of the final signal or image. In recent years, following developments in materials science and technology, several new methods have been successfully implemented for the preparation of nanosized phosphors. It is of interest to investigate whether nanophosphors could replace existing micro phosphors for next generation high-performance displays and imaging devices. The purpose of the present study was to investigate the variation of the optical parameters (e.g. light extinction coefficient mext, probability of light absorption p, light anisotropy factor g) in the sub-micron and nano scale under the variability of light wavelength (400-700 nm) and refractive index (e.g., two limiting values were used 1.4 and 2.0). For the case of low refractive index (1.4), by increasing the grain diameter: (a) the light extinction increases, (b) the light absorption probability decreases and (c) the anisotropy factor increases in the whole range or gran sizes (2-1000 nm). However, for the high value of the refractive index (2.0), the light extinction coefficient was found to increase up to a maximum for grain diameter: (a) 200 nm (at 400 nm light wavelength) and (b) 600 nm (at 700 nm light wavelength). Finally, at 400 nm grain diameter, the probability of light absorption was found to decrease down to a minimum while the anisotropy factor was found to increase up to maximum for all light wavelengths considered.
{"title":"Examination of the variation of the optical diffusion properties in nanophosphor materials for use in biomedical imaging and instrumentation","authors":"P. Liaparinos, I. Kandarakis","doi":"10.1117/12.2180591","DOIUrl":"https://doi.org/10.1117/12.2180591","url":null,"abstract":"Granular phosphors are commonly used in several applications in biomedical imaging and instrumentation. The structural and optical properties of phosphor materials affect the optical signal transferred out and play a critical role in the quality of the final signal or image. In recent years, following developments in materials science and technology, several new methods have been successfully implemented for the preparation of nanosized phosphors. It is of interest to investigate whether nanophosphors could replace existing micro phosphors for next generation high-performance displays and imaging devices. The purpose of the present study was to investigate the variation of the optical parameters (e.g. light extinction coefficient mext, probability of light absorption p, light anisotropy factor g) in the sub-micron and nano scale under the variability of light wavelength (400-700 nm) and refractive index (e.g., two limiting values were used 1.4 and 2.0). For the case of low refractive index (1.4), by increasing the grain diameter: (a) the light extinction increases, (b) the light absorption probability decreases and (c) the anisotropy factor increases in the whole range or gran sizes (2-1000 nm). However, for the high value of the refractive index (2.0), the light extinction coefficient was found to increase up to a maximum for grain diameter: (a) 200 nm (at 400 nm light wavelength) and (b) 600 nm (at 700 nm light wavelength). Finally, at 400 nm grain diameter, the probability of light absorption was found to decrease down to a minimum while the anisotropy factor was found to increase up to maximum for all light wavelengths considered.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121793124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The collagen fibers are one of the most important structural proteins in skin, being responsible for its strength and flexibility. It is known that their properties, like fibers density, ordination and mean diameter can be affected by several skin conditions, what makes these properties a good parameter to be used on the diagnosis and evaluation of skin aging, cancer, healing, among other conditions. There is, however, a need for methods capable of analyzing quantitatively the organization patterns of these fibers. To address this need, we developed a method based on the autocorrelation function of the images that allows the construction of vector field plots of the fibers directions and does not require any kind of curve fitting or optimization. The analyzed images were obtained through Second Harmonic Generation Imaging Microscopy. This paper presents a concise review on the autocorrelation function and some of its applications to image processing, details the developed method and the results obtained through the analysis of hystopathological slides of landrace porcine skin. The method has high accuracy on the determination of the fibers direction and presents high performance. We look forward to perform further studies keeping track of different skin conditions over time.
{"title":"Image correlation based method for the analysis of collagen fibers patterns","authors":"R. G. T. Rosa, S. Pratavieira, C. Kurachi","doi":"10.1117/12.2180920","DOIUrl":"https://doi.org/10.1117/12.2180920","url":null,"abstract":"The collagen fibers are one of the most important structural proteins in skin, being responsible for its strength and flexibility. It is known that their properties, like fibers density, ordination and mean diameter can be affected by several skin conditions, what makes these properties a good parameter to be used on the diagnosis and evaluation of skin aging, cancer, healing, among other conditions. There is, however, a need for methods capable of analyzing quantitatively the organization patterns of these fibers. To address this need, we developed a method based on the autocorrelation function of the images that allows the construction of vector field plots of the fibers directions and does not require any kind of curve fitting or optimization. The analyzed images were obtained through Second Harmonic Generation Imaging Microscopy. This paper presents a concise review on the autocorrelation function and some of its applications to image processing, details the developed method and the results obtained through the analysis of hystopathological slides of landrace porcine skin. The method has high accuracy on the determination of the fibers direction and presents high performance. We look forward to perform further studies keeping track of different skin conditions over time.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"2009 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127333199","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Zezell, M. N. Veloso, D. A. Dias, R. Politano, C. Benetti
We verified the changes promoted by ionizing radiation in bone tissue using FTIR. Samples of bovine bone were irradiated using Cobalt-60 with 0.01kGy, 0.1kGy, 1kGy, 15kGy and 75kGy. The effects of ionizing irradiation on chemical structure of bone, were studied considering the sub-bands of amide I, the crystallinity index and relation of organic and inorganic materials. ATR-FTIR spectroscopy showed changes in organic components and in hydroxyapatite crystals organization. High correlation with statistical significance was observed between (amideIII+collagen)/ ν1,ν3PO4, crystallinity and mechanical properties of the samples.
{"title":"In vitro evaluation of ionizing radiation effects in bone tissue by FTIR spectroscopy","authors":"D. Zezell, M. N. Veloso, D. A. Dias, R. Politano, C. Benetti","doi":"10.1117/12.2181096","DOIUrl":"https://doi.org/10.1117/12.2181096","url":null,"abstract":"We verified the changes promoted by ionizing radiation in bone tissue using FTIR. Samples of bovine bone were irradiated using Cobalt-60 with 0.01kGy, 0.1kGy, 1kGy, 15kGy and 75kGy. The effects of ionizing irradiation on chemical structure of bone, were studied considering the sub-bands of amide I, the crystallinity index and relation of organic and inorganic materials. ATR-FTIR spectroscopy showed changes in organic components and in hydroxyapatite crystals organization. High correlation with statistical significance was observed between (amideIII+collagen)/ ν1,ν3PO4, crystallinity and mechanical properties of the samples.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"12 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113943780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Liposomes have been used to deliver DNA, drugs and, more recently, nanoparticles such as quantum dots, into living cells. Their electrostatic interaction with cell’s surface (negatively charged) can lead to membrane destabilization and/or fusion, facilitating intracellular release of those compounds. Nevertheless, cationic lipids can modify living cells homeostasis, depending on their concentration. In this study, we observed that the DOTAP cationic lipid concentrations influence the red blood cells (RBCs) homeostasis. We used fluorescent fusogenic liposomes composed by three lipids: DOPE, DOTAP and DPPE-Rhodamine (1:0.1/0.3/0.5/0.8/1:0.1 mM respectively), varying DOTAP from 0.1 to 1 mM. To probe liposomes ability to fuse with cells, RBCs (1% in saline) were utilized. Liposomes were characterized by zeta potential, dynamic light scattering (DLS), fluorescence and transmission electron microscopy. Their interaction with RBCs was evaluated by fluorescence microscopy and flow cytometry. Zeta potential results showed that, from 0.1 to 1 mM concentration, the charge increases, due to the addition of DOTAP. Liposomes’ diameter does not vary significantly when more DOTAP was added, except for the one containing 0.1 mM of DOTAP, according to DLS results. Flow cytometry and microscopy analysis showed that for all DOTAP’ concentration applied, the liposomes were capable to label RBCs. However, as higher the amount of DOTAP in liposomes, the more harmful they were to cells. Thus, the results showed that it is possible to use lower concentrations of DOTAP keeping the fusogenic liposomes’s ability and cell homeostasis. This is important to guarantee a greater efficiency in the delivery of nanoparticles or other active samples into cells.
脂质体已被用于将DNA、药物以及最近的量子点等纳米粒子输送到活细胞中。它们与细胞表面(带负电荷)的静电相互作用可导致膜不稳定和/或融合，促进细胞内释放这些化合物。然而，阳离子脂质可以改变活细胞的稳态，这取决于它们的浓度。在这项研究中，我们观察到DOTAP阳离子脂质浓度影响红细胞(rbc)稳态。我们使用由三种脂质组成的荧光融合脂质体:DOPE, DOTAP和dpe -罗丹明(分别为1:0.1/0.3/0.5/0.8/1:0.1 mM)， DOTAP从0.1到1 mM不等。为了探测脂质体与细胞融合的能力，使用了红细胞(1%盐水)。采用zeta电位、动态光散射(DLS)、荧光和透射电镜对脂质体进行表征。通过荧光显微镜和流式细胞术评估它们与红细胞的相互作用。Zeta电位结果表明，在0.1 ~ 1mm浓度范围内，DOTAP的加入使电荷增加。DLS结果显示，除了含有0.1 mM DOTAP的脂质体外，添加更多DOTAP的脂质体直径没有显著变化。流式细胞术和显微镜分析显示，对于所有浓度的DOTAP，脂质体都能够标记红细胞。然而，脂质体中DOTAP含量越高，对细胞的危害越大。因此，结果表明，可以使用较低浓度的DOTAP来保持促聚变脂质体的能力和细胞稳态。这对于保证纳米颗粒或其他活性样品进入细胞的更高效率是很重要的。
{"title":"Fluorescent liposomes to probe how DOTAP lipid concentrations can change red blood cells homeostasis","authors":"A. L. Matos, G. Pereira, B. S. Santos, A. Fontes","doi":"10.1117/12.2180957","DOIUrl":"https://doi.org/10.1117/12.2180957","url":null,"abstract":"Liposomes have been used to deliver DNA, drugs and, more recently, nanoparticles such as quantum dots, into living cells. Their electrostatic interaction with cell’s surface (negatively charged) can lead to membrane destabilization and/or fusion, facilitating intracellular release of those compounds. Nevertheless, cationic lipids can modify living cells homeostasis, depending on their concentration. In this study, we observed that the DOTAP cationic lipid concentrations influence the red blood cells (RBCs) homeostasis. We used fluorescent fusogenic liposomes composed by three lipids: DOPE, DOTAP and DPPE-Rhodamine (1:0.1/0.3/0.5/0.8/1:0.1 mM respectively), varying DOTAP from 0.1 to 1 mM. To probe liposomes ability to fuse with cells, RBCs (1% in saline) were utilized. Liposomes were characterized by zeta potential, dynamic light scattering (DLS), fluorescence and transmission electron microscopy. Their interaction with RBCs was evaluated by fluorescence microscopy and flow cytometry. Zeta potential results showed that, from 0.1 to 1 mM concentration, the charge increases, due to the addition of DOTAP. Liposomes’ diameter does not vary significantly when more DOTAP was added, except for the one containing 0.1 mM of DOTAP, according to DLS results. Flow cytometry and microscopy analysis showed that for all DOTAP’ concentration applied, the liposomes were capable to label RBCs. However, as higher the amount of DOTAP in liposomes, the more harmful they were to cells. Thus, the results showed that it is possible to use lower concentrations of DOTAP keeping the fusogenic liposomes’s ability and cell homeostasis. This is important to guarantee a greater efficiency in the delivery of nanoparticles or other active samples into cells.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"399 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124743534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. D. O. Gonçalves, Thiago da Silva Cordeiro, Flávia R. O. Silva, R. Samad, N. D. Vieira Junior, Lilia Coronato Courrol
The use of gold nanoparticles (AuNps) as the vehicle for 5-Aminolevulinic acid (ALA) delivery for photodynamic and photothermic plasmonic therapies is a promising approach, especially with the recent demonstration that this photosensitizer immobilization on the particle surface improves reactive oxygen species (ROS) formation, increasing its cytotoxicity. Gold nanorods (AuNRs) present an absorption spectrum shifted to 700 nm, within the tissue transparency window, which allows excitation of the nanoparticles situated deeper in the tissues. Here, we describe a new synthesis method that was applied to control the shape of the gold nanoparticles during its synthesis. To obtain ALA:AuNRs, precursor ALA:AuNps were irradiated by ultrashort laser pulses. The variation of the laser parameters such as pulse energy and duration and irradiation time was assessed. The relevant mechanisms are discussed.
{"title":"Preparation and optimization of aminolevulinic acid with gold nanoparticles for photothermal and photodynamic therapies applications","authors":"K. D. O. Gonçalves, Thiago da Silva Cordeiro, Flávia R. O. Silva, R. Samad, N. D. Vieira Junior, Lilia Coronato Courrol","doi":"10.1117/12.2180017","DOIUrl":"https://doi.org/10.1117/12.2180017","url":null,"abstract":"The use of gold nanoparticles (AuNps) as the vehicle for 5-Aminolevulinic acid (ALA) delivery for photodynamic and photothermic plasmonic therapies is a promising approach, especially with the recent demonstration that this photosensitizer immobilization on the particle surface improves reactive oxygen species (ROS) formation, increasing its cytotoxicity. Gold nanorods (AuNRs) present an absorption spectrum shifted to 700 nm, within the tissue transparency window, which allows excitation of the nanoparticles situated deeper in the tissues. Here, we describe a new synthesis method that was applied to control the shape of the gold nanoparticles during its synthesis. To obtain ALA:AuNRs, precursor ALA:AuNps were irradiated by ultrashort laser pulses. The variation of the laser parameters such as pulse energy and duration and irradiation time was assessed. The relevant mechanisms are discussed.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123302469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. M. L. Terena, K. Fernandes, S. Kalil, A. N. Alves, R. A. Mesquita Ferrari
The hypertrophy is known as an increase the cross-sectional area of the muscle as a result of a muscular work against an overload, and it is compensatory because the overload is induced by functional elimination of synergistic muscles. The importance of study the compensatory hypertrophy is understand how this process can be influenced by the irradiation with regard to the weight and muscle cross-sectional area, to assist in the rehabilitation process and the effectiveness functional return. The aim was evaluate the effects of low-level laser irradiation on morphological aspects of muscle tissue, comparing the weight and cross-sectional area in rat skeletal muscle. Wistar rats were divided into three groups: control, hypertrophy group without irradiation (right plantar muscle) and hypertrophy group and irradiation (left plantar muscle), both analyzed after 7 and 14 days. The irradiation was performed daily immediately after the surgery. The parameters were: λ = 780nm, beam spot of 0.04 cm2, output power of 40mW, power density of 1W/cm2, energy density of 10J / cm2 and 10s exposure time with a total energy of 3.2 J. The results revealed that low level laser irradiation an increase the weight of the plantaris muscle after 7 and 14 days with a difference of 7.06% and 11.51% respectively. In conclusion, low level laser irradiation has an effect on compensatory hypertrophy to produce increased muscle weight and promoted an increase in cross-sectional area of muscle fibers in the compensatory hypertrophy model after 14 days with parameters cited above.
{"title":"Effects of low level laser in the morphology of the skeletal muscle fiber during compensatory hypertrophy in plantar muscle of rats","authors":"S. M. L. Terena, K. Fernandes, S. Kalil, A. N. Alves, R. A. Mesquita Ferrari","doi":"10.1117/12.2181034","DOIUrl":"https://doi.org/10.1117/12.2181034","url":null,"abstract":"The hypertrophy is known as an increase the cross-sectional area of the muscle as a result of a muscular work against an overload, and it is compensatory because the overload is induced by functional elimination of synergistic muscles. The importance of study the compensatory hypertrophy is understand how this process can be influenced by the irradiation with regard to the weight and muscle cross-sectional area, to assist in the rehabilitation process and the effectiveness functional return. The aim was evaluate the effects of low-level laser irradiation on morphological aspects of muscle tissue, comparing the weight and cross-sectional area in rat skeletal muscle. Wistar rats were divided into three groups: control, hypertrophy group without irradiation (right plantar muscle) and hypertrophy group and irradiation (left plantar muscle), both analyzed after 7 and 14 days. The irradiation was performed daily immediately after the surgery. The parameters were: λ = 780nm, beam spot of 0.04 cm2, output power of 40mW, power density of 1W/cm2, energy density of 10J / cm2 and 10s exposure time with a total energy of 3.2 J. The results revealed that low level laser irradiation an increase the weight of the plantaris muscle after 7 and 14 days with a difference of 7.06% and 11.51% respectively. In conclusion, low level laser irradiation has an effect on compensatory hypertrophy to produce increased muscle weight and promoted an increase in cross-sectional area of muscle fibers in the compensatory hypertrophy model after 14 days with parameters cited above.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117331462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R. Lizarelli, Natália D. P. Grandi, F. Florez, C. Grecco, L. A. Lopes
Skin hydration is important to prevent aging and dysfunction of orofacial system. Nowadays, it is known that cutaneous system is linked to muscle system, then every dentist need to treat healthy facial skin, as lips, keeping orofacial functions healthy. Thirty-two patients were treated using laser and led therapy single or associated to biomaterials (dermo-cosmetics) searching for the best protocol to promote skin hydration. Using a peace of equipment to measure electric impedance, percentage of water and oil from skin, before and after different treatments were analyzed. Statistic tests using 5% and 0.1% of significance were applied and results showed that light could improve hydration of epidermis layer of facial skin. Considering just light effect, using infrared laser followed by blue led system is more effective to hydration than just blue led system application. Considering dermo-cosmetic and light, the association between both presented the best result.
{"title":"Clinical study on orofacial photonic hydration using phototherapy and biomaterials","authors":"R. Lizarelli, Natália D. P. Grandi, F. Florez, C. Grecco, L. A. Lopes","doi":"10.1117/12.2181132","DOIUrl":"https://doi.org/10.1117/12.2181132","url":null,"abstract":"Skin hydration is important to prevent aging and dysfunction of orofacial system. Nowadays, it is known that cutaneous system is linked to muscle system, then every dentist need to treat healthy facial skin, as lips, keeping orofacial functions healthy. Thirty-two patients were treated using laser and led therapy single or associated to biomaterials (dermo-cosmetics) searching for the best protocol to promote skin hydration. Using a peace of equipment to measure electric impedance, percentage of water and oil from skin, before and after different treatments were analyzed. Statistic tests using 5% and 0.1% of significance were applied and results showed that light could improve hydration of epidermis layer of facial skin. Considering just light effect, using infrared laser followed by blue led system is more effective to hydration than just blue led system application. Considering dermo-cosmetic and light, the association between both presented the best result.","PeriodicalId":307847,"journal":{"name":"Biophotonics South America","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121631984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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