The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Ana Grenha - One of the best experts on this subject based on the ideXlab platform.
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Carrageenan from red algae: an application in the development of inhalable tuberculosis therapy targeting the macrophages
Drug Delivery and Translational Research, 2020Co-Authors: Susana Rodrigues, Maria Leonor Faleiro, Francesca Buttini, Ludmylla Cunha, João Rico, Ana M. Rosa Da Costa, António J. Almeida, Ana GrenhaAbstract:Macrophages have unique surface receptors that might recognize preferentially several moieties present on the surface of infecting organisms, including in the bacterial cell wall. Benefiting from a similar composition regarding the referred moieties, polysaccharides might be good candidates to compose the matrix of drug carriers aimed at macrophage targeting, as they can use the same recognition pathways of the infecting organisms. Carrageenan (CRG), a polysaccharide extracted from red edible seaweed, is an interesting possibility for the approach of directly targeting alveolar macrophages, as its composition is reported to be recognized by several macrophage lectin receptors. Inhalable starch/CRG microparticles were successfully produced, effectively associating isoniazid (96%) and rifabutin (74%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the Respiratory Zone, with a mass median aerodynamic diameter (MMAD) between 3.3 and 3.9 μm. It was further demonstrated that the antitubercular activity of the drugs remained unchanged after encapsulation. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells for the drug-loaded formulation. Starch/CRG microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. This work provides indications on the potential of the starch/CRG carriers to interact with macrophages, thus providing a platform for drug delivery in the context of macrophage intracellular diseases. Additionally, if tuberculosis is focused, these microparticles can be used as inhalable drug carriers. Graphical abstractz
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Inhalable Fucoidan Microparticles Combining Two Antitubercular Drugs with Potential Application in Pulmonary Tuberculosis Therapy
Polymers, 2018Co-Authors: L. F. Cunha, Susana Rodrigues, Ana M. Rosa Da Costa, Maria Leonor Faleiro, Francesca Buttini, Ana GrenhaAbstract:The pulmonary delivery of antitubercular drugs is a promising approach to treat lung tuberculosis. This strategy not only allows targeting the infected organ instantly, it can also reduce the systemic adverse effects of the antibiotics. In light of that, this work aimed at producing fucoidan-based inhalable microparticles that are able to associate a combination of two first-line antitubercular drugs in a single formulation. Fucoidan is a polysaccharide composed of chemical units that have been reported to be specifically recognised by alveolar macrophages (the hosts of Mycobacterium). Inhalable fucoidan microparticles were successfully produced, effectively associating isoniazid (97%) and rifabutin (95%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the Respiratory Zone, with a mass median aerodynamic diameter (MMAD) between 3.6–3.9 µm. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells at the highest tested concentration (1 mg/mL). Fucoidan microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. Furthermore, drug-loaded microparticles effectively inhibited mycobacterial growth in vitro. Thus, the produced fucoidan microparticles are considered to hold potential as pulmonary delivery systems for the treatment of tuberculosis.
Mahdi Jalali - One of the best experts on this subject based on the ideXlab platform.
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Simulation of lead fume emissions in the workplace using computational fluid dynamics in the electronics industry
Environmental Science and Pollution Research, 2020Co-Authors: Somayeh Rahimi Moghadam, Mahmoud Mohammadyan, Amin Markani, Narges Khanjani, Mahdi JalaliAbstract:Computational fluid dynamics (CFD) is a powerful method for predicting the release of pollutants in the workplace and has recently been used as a valuable tool by health authorities. The purpose of this study was to predict the distribution of lead fume in the workplace using computational fluid dynamics in the electronics manufacturing industry. A cross-sectional descriptive and analytical study was conducted in the Neyshabur electronics industry (2019). Individual exposure to lead fume was measured by the OSHA121 method. Simulation and prediction of lead fume emission in the workplace were done using computational fluid dynamics and by the ANSYS16 software. The mean of personal exposure to lead fumes was 0.04 ± 0.01 mg/m^3. The software predicted the distribution of lead fumes in the Respiratory Zone of the worker to be in the range of 0.04 to 0.07 mg/m^3, which is very close to the real values. By doubling the suction power of the topical ventilation used, workers’ exposure to lead fumes was nearly halved and reached well below the recommended limit. The results showed that CFD is a useful tool for simulating individual contact with pollutants in a geometry. Also, given that the CFD shows the diffusion and distribution of pollutants in all points of a geometry, it is useful to indicate critical locations and conditions.
Masayuki Ikeda - One of the best experts on this subject based on the ideXlab platform.
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Exposure-excretion relationship of styrene and acetone in factory workers: A comparison of a lipophilic solvent and a hydrophilic solvent
Archives of Environmental Contamination and Toxicology, 1993Co-Authors: Kazunori Mizunuma, Tomojiro Yasugi, Toshio Kawai, Shun'ichi Horiguchi, Masayuki IkedaAbstract:A factory survey was conducted in the second half of a working week on 41 exposed male workers, who were engaged in fiber-reinforced plastics work and exposed to the mixed vapors of styrene and acetone. Nonexposed workers, 20 men, were recruited from the same factory. Styrene and acetone in Respiratory Zone air were monitored for a 8-h shift with carbon cloth- and water-equipped personal diffusive samplers, respectively. Blood and urine samples were collected at the shift-end. Acetone and styrene concentrations in whole blood, serum and urine were measured by head-space gas chromatography, and phenylglyoxylic acid in urine by high-performance liquid chromatography. All biological exposure indicators analyzed correlated significantly with the intensity of exposure to the corresponding solvent during the shift. The slopes of the regression lines indicate that a very small fraction of styrene absorbed will be excreted into urine as styrene per se , and that styrene is quite effectively excreted into urine after metabolic conversion. In contrast, the slopes of regression lines for acetone suggest that acetone distributes both in the blood and urine quite evenly. When the distribution of the solvent in serum was compared with that in the whole blood, it was found that almost all of styrene in blood is present in the serum, whereas acetone distributed very evenly in the cellular and noncellular fractions of the blood.
Susana Rodrigues - One of the best experts on this subject based on the ideXlab platform.
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Carrageenan from red algae: an application in the development of inhalable tuberculosis therapy targeting the macrophages
Drug Delivery and Translational Research, 2020Co-Authors: Susana Rodrigues, Maria Leonor Faleiro, Francesca Buttini, Ludmylla Cunha, João Rico, Ana M. Rosa Da Costa, António J. Almeida, Ana GrenhaAbstract:Macrophages have unique surface receptors that might recognize preferentially several moieties present on the surface of infecting organisms, including in the bacterial cell wall. Benefiting from a similar composition regarding the referred moieties, polysaccharides might be good candidates to compose the matrix of drug carriers aimed at macrophage targeting, as they can use the same recognition pathways of the infecting organisms. Carrageenan (CRG), a polysaccharide extracted from red edible seaweed, is an interesting possibility for the approach of directly targeting alveolar macrophages, as its composition is reported to be recognized by several macrophage lectin receptors. Inhalable starch/CRG microparticles were successfully produced, effectively associating isoniazid (96%) and rifabutin (74%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the Respiratory Zone, with a mass median aerodynamic diameter (MMAD) between 3.3 and 3.9 μm. It was further demonstrated that the antitubercular activity of the drugs remained unchanged after encapsulation. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells for the drug-loaded formulation. Starch/CRG microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. This work provides indications on the potential of the starch/CRG carriers to interact with macrophages, thus providing a platform for drug delivery in the context of macrophage intracellular diseases. Additionally, if tuberculosis is focused, these microparticles can be used as inhalable drug carriers. Graphical abstractz
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Inhalable Fucoidan Microparticles Combining Two Antitubercular Drugs with Potential Application in Pulmonary Tuberculosis Therapy
Polymers, 2018Co-Authors: L. F. Cunha, Susana Rodrigues, Ana M. Rosa Da Costa, Maria Leonor Faleiro, Francesca Buttini, Ana GrenhaAbstract:The pulmonary delivery of antitubercular drugs is a promising approach to treat lung tuberculosis. This strategy not only allows targeting the infected organ instantly, it can also reduce the systemic adverse effects of the antibiotics. In light of that, this work aimed at producing fucoidan-based inhalable microparticles that are able to associate a combination of two first-line antitubercular drugs in a single formulation. Fucoidan is a polysaccharide composed of chemical units that have been reported to be specifically recognised by alveolar macrophages (the hosts of Mycobacterium). Inhalable fucoidan microparticles were successfully produced, effectively associating isoniazid (97%) and rifabutin (95%) simultaneously. Furthermore, the produced microparticles presented adequate aerodynamic properties for pulmonary delivery with potential to reach the Respiratory Zone, with a mass median aerodynamic diameter (MMAD) between 3.6–3.9 µm. The formulation evidenced no cytotoxic effects on lung epithelial cells (A549), although mild toxicity was observed on macrophage-differentiated THP-1 cells at the highest tested concentration (1 mg/mL). Fucoidan microparticles also exhibited a propensity to be captured by macrophages in a dose-dependent manner, as well as an ability to activate the target cells. Furthermore, drug-loaded microparticles effectively inhibited mycobacterial growth in vitro. Thus, the produced fucoidan microparticles are considered to hold potential as pulmonary delivery systems for the treatment of tuberculosis.
Somayeh Rahimi Moghadam - One of the best experts on this subject based on the ideXlab platform.
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Simulation of lead fume emissions in the workplace using computational fluid dynamics in the electronics industry
Environmental Science and Pollution Research, 2020Co-Authors: Somayeh Rahimi Moghadam, Mahmoud Mohammadyan, Amin Markani, Narges Khanjani, Mahdi JalaliAbstract:Computational fluid dynamics (CFD) is a powerful method for predicting the release of pollutants in the workplace and has recently been used as a valuable tool by health authorities. The purpose of this study was to predict the distribution of lead fume in the workplace using computational fluid dynamics in the electronics manufacturing industry. A cross-sectional descriptive and analytical study was conducted in the Neyshabur electronics industry (2019). Individual exposure to lead fume was measured by the OSHA121 method. Simulation and prediction of lead fume emission in the workplace were done using computational fluid dynamics and by the ANSYS16 software. The mean of personal exposure to lead fumes was 0.04 ± 0.01 mg/m^3. The software predicted the distribution of lead fumes in the Respiratory Zone of the worker to be in the range of 0.04 to 0.07 mg/m^3, which is very close to the real values. By doubling the suction power of the topical ventilation used, workers’ exposure to lead fumes was nearly halved and reached well below the recommended limit. The results showed that CFD is a useful tool for simulating individual contact with pollutants in a geometry. Also, given that the CFD shows the diffusion and distribution of pollutants in all points of a geometry, it is useful to indicate critical locations and conditions.