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
Antibiotic resistance has been compromised hospitalized patients with serious infections. The main cases of bacteremia can be caused by antibiotic resistant pathogens. Photodynamic therapy （PDT） has been shown as an...Antibiotic resistance has been compromised hospitalized patients with serious infections. The main cases of bacteremia can be caused by antibiotic resistant pathogens. Photodynamic therapy （PDT） has been shown as an alternative for inactivation of microorganisms in blood. In this therapy photochemical mechanisms occur that may prevent the development of bacteria. This study aims optimization of PDT parameters for blood decontamination. Concentration ofphotosensitizer （PS）, light dose （LD） and incubation time （IT） were studied for hemolysis and cell toxic effects. It was observed that PDT can be used for microbial inactivation in total blood reducing 0.85 log10 CFU/mL ofS. aureus at 15 J/cm^2 and 50μg/mL of Photogem .展开更多
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.
文摘Antibiotic resistance has been compromised hospitalized patients with serious infections. The main cases of bacteremia can be caused by antibiotic resistant pathogens. Photodynamic therapy （PDT） has been shown as an alternative for inactivation of microorganisms in blood. In this therapy photochemical mechanisms occur that may prevent the development of bacteria. This study aims optimization of PDT parameters for blood decontamination. Concentration ofphotosensitizer （PS）, light dose （LD） and incubation time （IT） were studied for hemolysis and cell toxic effects. It was observed that PDT can be used for microbial inactivation in total blood reducing 0.85 log10 CFU/mL ofS. aureus at 15 J/cm^2 and 50μg/mL of Photogem .
