Photodynamic therapy (PDT) is a treatment modality that has advanced rapidly in recent years. It causes tissue and vascular damage with the interaction of a photosensitizing agent (PS), light of a proper wavelength, a...Photodynamic therapy (PDT) is a treatment modality that has advanced rapidly in recent years. It causes tissue and vascular damage with the interaction of a photosensitizing agent (PS), light of a proper wavelength, and molecular oxygen. Evaluation of vessel damage usually relies on histopathology evaluation. Results are often qualitative or at best semi-quantitative based on a subjective system. The aim of this study was to evaluate, using CD31 immunohistochemistry and image analysis software, the vascular damage after PDT in a well-established rodent model of chemically induced mammary tumor. Fourteen Sprague-Dawley rats received a single dose of 7,12-dimethylbenz(a)anthraxcene (80 mg/kg by gavage), treatment efficacy was evaluated by comparing the vascular density of tumors after treatment with Photogem®?as a PS, intraperitoneally, followed by interstitial fiber optic lighting, from a diode laser, at 200 mW/cm and light dose of 100 J/cm directed against his tumor (7 animals), with a control group (6 animals, no PDT). The animals were euthanized 30 hours after the lighting and mammary tumors were removed and samples from each lesion were formalin-fixed. Immunostained blood vessels were quantified by Image Pro-Plus version 7.0. The control group had an average of 3368.6 ± 4027.1 pixels per picture and the treated group had an average of 779 ± 1242.6 pixels per area (P 0.01), indicating that PDT caused a significant decrease in vascular density of mammary tumors. The combined immunohistochemistry using CD31, with selection of representative areas by a trained pathology, followed by quantification of staining using Image Pro-Plus version 7.0 system was a practical and robust methodology for vessel damage evaluation, which probably could be used to assess other antiangiogenic treatments.展开更多
Background:Microorganisms transferred by water,air,and human such as bacteria and viruses can reach inanimate surfaces with high rates of contamination.In general,the objectives of the research were to evaluate the de...Background:Microorganisms transferred by water,air,and human such as bacteria and viruses can reach inanimate surfaces with high rates of contamination.In general,the objectives of the research were to evaluate the decontamination of large areas such as floors,using a mobile device with ultraviolet C light at different delivery times and also to evaluate these microbial loads in stationary or latent phases.Material and methods:The microbial inactivation effects of this device were measured through the recovery of viable bacteria in different points of the applied area.Results:A significant microbial reduction(p≤0.05)of 60-87%was obtained in general for all groups and for groups with stationary phase reductions of 100%.Conclusions:microbial inactivation with UV-C ultraviolet light administration rates presents the possibility of potential use on surfaces of large areas for the decontamination of microorganisms in latent and stationary phases.展开更多
Background: As is observed in acute respiratory pandemics characterized by inflammation of the oropharynx, microbial transmission caused by viruses and bacteria through the upper respiratory tract can quickly affect t...Background: As is observed in acute respiratory pandemics characterized by inflammation of the oropharynx, microbial transmission caused by viruses and bacteria through the upper respiratory tract can quickly affect the lower respiratory tract due to its ease of transmission, The challenges are presented in the development of an adequate lighting system to prevent infections of the upper respiratory treatment and highlight the importance of following the procedure due to fluorescence decay from the given light dose. Methods: for this purpose, our study evaluated the lighting distribution on the oropharynx established and determined under simulation by TracePro software. The photobleaching (PB) is obtained by different fluorescence analysis methods of photosensitizer (PS) in formulation located in the oropharynx and tonsils. A blue light emission system at 450 nm was studied to improve the distribution, uniformity, and ray’s incidence. The PB of the PS was investigated using two different methods for detecting fluorescence in the oropharynx by quantifying the active portion of the PS assessed by fluorescence spectroscopy for patients with pharyngotonsillitis by consuming 2.25 mg of curcumin in formulation after applying light by analysis of images in Software MatLab. Results: The lighting device showed a uniformity of 82% in the oropharynx. In healthy volunteers, the minimum energy of photodegradation of curcumin is 0.2 and the maximum energy is 17.4 J/cm2. We observed intensities of blue and green emission of the analyzed fluorescence images related to PS through fluorescence measurements. Conclusions: We conclude that the pharyngotonsillitis infections can be treated by using an adequate distribution of light in the oropharynx and by activating photosensitizing agents in the infection sites supported by the fluorescence of the compound.展开更多
文摘Photodynamic therapy (PDT) is a treatment modality that has advanced rapidly in recent years. It causes tissue and vascular damage with the interaction of a photosensitizing agent (PS), light of a proper wavelength, and molecular oxygen. Evaluation of vessel damage usually relies on histopathology evaluation. Results are often qualitative or at best semi-quantitative based on a subjective system. The aim of this study was to evaluate, using CD31 immunohistochemistry and image analysis software, the vascular damage after PDT in a well-established rodent model of chemically induced mammary tumor. Fourteen Sprague-Dawley rats received a single dose of 7,12-dimethylbenz(a)anthraxcene (80 mg/kg by gavage), treatment efficacy was evaluated by comparing the vascular density of tumors after treatment with Photogem®?as a PS, intraperitoneally, followed by interstitial fiber optic lighting, from a diode laser, at 200 mW/cm and light dose of 100 J/cm directed against his tumor (7 animals), with a control group (6 animals, no PDT). The animals were euthanized 30 hours after the lighting and mammary tumors were removed and samples from each lesion were formalin-fixed. Immunostained blood vessels were quantified by Image Pro-Plus version 7.0. The control group had an average of 3368.6 ± 4027.1 pixels per picture and the treated group had an average of 779 ± 1242.6 pixels per area (P 0.01), indicating that PDT caused a significant decrease in vascular density of mammary tumors. The combined immunohistochemistry using CD31, with selection of representative areas by a trained pathology, followed by quantification of staining using Image Pro-Plus version 7.0 system was a practical and robust methodology for vessel damage evaluation, which probably could be used to assess other antiangiogenic treatments.
文摘Background:Microorganisms transferred by water,air,and human such as bacteria and viruses can reach inanimate surfaces with high rates of contamination.In general,the objectives of the research were to evaluate the decontamination of large areas such as floors,using a mobile device with ultraviolet C light at different delivery times and also to evaluate these microbial loads in stationary or latent phases.Material and methods:The microbial inactivation effects of this device were measured through the recovery of viable bacteria in different points of the applied area.Results:A significant microbial reduction(p≤0.05)of 60-87%was obtained in general for all groups and for groups with stationary phase reductions of 100%.Conclusions:microbial inactivation with UV-C ultraviolet light administration rates presents the possibility of potential use on surfaces of large areas for the decontamination of microorganisms in latent and stationary phases.
基金The authors thank the Brazilian research funding agencies FAPESP(2013/07276-1 and 2019/12694-3)for the financial support of this work.
文摘Background: As is observed in acute respiratory pandemics characterized by inflammation of the oropharynx, microbial transmission caused by viruses and bacteria through the upper respiratory tract can quickly affect the lower respiratory tract due to its ease of transmission, The challenges are presented in the development of an adequate lighting system to prevent infections of the upper respiratory treatment and highlight the importance of following the procedure due to fluorescence decay from the given light dose. Methods: for this purpose, our study evaluated the lighting distribution on the oropharynx established and determined under simulation by TracePro software. The photobleaching (PB) is obtained by different fluorescence analysis methods of photosensitizer (PS) in formulation located in the oropharynx and tonsils. A blue light emission system at 450 nm was studied to improve the distribution, uniformity, and ray’s incidence. The PB of the PS was investigated using two different methods for detecting fluorescence in the oropharynx by quantifying the active portion of the PS assessed by fluorescence spectroscopy for patients with pharyngotonsillitis by consuming 2.25 mg of curcumin in formulation after applying light by analysis of images in Software MatLab. Results: The lighting device showed a uniformity of 82% in the oropharynx. In healthy volunteers, the minimum energy of photodegradation of curcumin is 0.2 and the maximum energy is 17.4 J/cm2. We observed intensities of blue and green emission of the analyzed fluorescence images related to PS through fluorescence measurements. Conclusions: We conclude that the pharyngotonsillitis infections can be treated by using an adequate distribution of light in the oropharynx and by activating photosensitizing agents in the infection sites supported by the fluorescence of the compound.
