36 research outputs found
Water extracts of cabbage and kale inhibit ex vivo H2O2-induced DNA damage but not rat hepatocarcinogenesis
Separation of Cells and Microparticles in Insulator-Based Electrokinetic Systems
Presented
here is the first continuous separation of microparticles
and cells of similar characteristics employing linear and nonlinear
electrokinetic phenomena in an insulator-based electrokinetic (iEK)
system. By utilizing devices with insulating features, which distort
the electric field distribution, it is possible to combine linear
and nonlinear EK phenomena, resulting in highly effective separation
schemes that leverage the new advancements in nonlinear electrophoresis.
This work combines mathematical modeling and experimentation to separate
four distinct binary mixtures of particles and cells. A computational
model with COMSOL Multiphysics was used to predict the retention times
(tR,p) of the particles and cells in iEK
devices. Then, the experimental separations were carried out using
the conditions identified with the model, where the experimental retention
time (tR,e) of the particles and cells
was measured. A total of four distinct separations of binary mixtures
were performed by increasing the level of difficulty. For the first
separation, two types of polystyrene microparticles, selected to mimic Escherichia coli and Saccharomyces
cerevisiae cells, were separated. By leveraging the
knowledge gathered from the first separation, a mixture of cells of
distinct domains and significant size differences, E. coli and S. cerevisiae, was successfully separated. The third separation also featured
cells of different domains but closer in size: Bacillus
cereus versus S. cerevisiae. The last separation included cells in the same domain and genus, B. cereus versus Bacillus subtilis. Separation results were evaluated in terms of number of plates
(N) and separation resolution (Rs), where Rs values for all
separations were above 1.5, illustrating complete separations. Experimental
results were in agreement with modeling results in terms of retention
times, with deviations in the 6–27% range, while the variation
between repetitions was between 2 and 18%, demonstrating good reproducibility.
This report is the first prediction of the retention time of cells
in iEK systems
Sensitivity of human pancreatic islets to peroxynitrite-induced cell dysfunction and death.
Nitric oxide and peroxynitrite (generated by the reaction of nitric oxide with the superoxide anion) may both be mediators of beta-cell damage in early insulin-dependent diabetes mellitus. We observed that acute exposure of primary cultured human pancreatic islets to peroxynitrite results in a significant decrease in glucose oxidation and islet retrieval. DNA strand breaks in single human and rat islet cells are detectable after acute peroxynitrite exposure, followed by a decrease in islet cell survival after 1 h and 24 h. Cell death appeared to occur via a toxic cell death mechanism (necrosis) rather than apoptosis, as suggested by vital staining and ultrastructural evidence of early membrane and organelle degradation, mitochondrial swelling and loss of matrix. This study demonstrates for the first time that cultured human pancreatic islets are susceptible to the noxious effects of peroxynitrite.Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe
Separation of Cells and Microparticles in Insulator-Based Electrokinetic Systems
Presented
here is the first continuous separation of microparticles
and cells of similar characteristics employing linear and nonlinear
electrokinetic phenomena in an insulator-based electrokinetic (iEK)
system. By utilizing devices with insulating features, which distort
the electric field distribution, it is possible to combine linear
and nonlinear EK phenomena, resulting in highly effective separation
schemes that leverage the new advancements in nonlinear electrophoresis.
This work combines mathematical modeling and experimentation to separate
four distinct binary mixtures of particles and cells. A computational
model with COMSOL Multiphysics was used to predict the retention times
(tR,p) of the particles and cells in iEK
devices. Then, the experimental separations were carried out using
the conditions identified with the model, where the experimental retention
time (tR,e) of the particles and cells
was measured. A total of four distinct separations of binary mixtures
were performed by increasing the level of difficulty. For the first
separation, two types of polystyrene microparticles, selected to mimic Escherichia coli and Saccharomyces
cerevisiae cells, were separated. By leveraging the
knowledge gathered from the first separation, a mixture of cells of
distinct domains and significant size differences, E. coli and S. cerevisiae, was successfully separated. The third separation also featured
cells of different domains but closer in size: Bacillus
cereus versus S. cerevisiae. The last separation included cells in the same domain and genus, B. cereus versus Bacillus subtilis. Separation results were evaluated in terms of number of plates
(N) and separation resolution (Rs), where Rs values for all
separations were above 1.5, illustrating complete separations. Experimental
results were in agreement with modeling results in terms of retention
times, with deviations in the 6–27% range, while the variation
between repetitions was between 2 and 18%, demonstrating good reproducibility.
This report is the first prediction of the retention time of cells
in iEK systems
Separation of Cells and Microparticles in Insulator-Based Electrokinetic Systems
Presented
here is the first continuous separation of microparticles
and cells of similar characteristics employing linear and nonlinear
electrokinetic phenomena in an insulator-based electrokinetic (iEK)
system. By utilizing devices with insulating features, which distort
the electric field distribution, it is possible to combine linear
and nonlinear EK phenomena, resulting in highly effective separation
schemes that leverage the new advancements in nonlinear electrophoresis.
This work combines mathematical modeling and experimentation to separate
four distinct binary mixtures of particles and cells. A computational
model with COMSOL Multiphysics was used to predict the retention times
(tR,p) of the particles and cells in iEK
devices. Then, the experimental separations were carried out using
the conditions identified with the model, where the experimental retention
time (tR,e) of the particles and cells
was measured. A total of four distinct separations of binary mixtures
were performed by increasing the level of difficulty. For the first
separation, two types of polystyrene microparticles, selected to mimic Escherichia coli and Saccharomyces
cerevisiae cells, were separated. By leveraging the
knowledge gathered from the first separation, a mixture of cells of
distinct domains and significant size differences, E. coli and S. cerevisiae, was successfully separated. The third separation also featured
cells of different domains but closer in size: Bacillus
cereus versus S. cerevisiae. The last separation included cells in the same domain and genus, B. cereus versus Bacillus subtilis. Separation results were evaluated in terms of number of plates
(N) and separation resolution (Rs), where Rs values for all
separations were above 1.5, illustrating complete separations. Experimental
results were in agreement with modeling results in terms of retention
times, with deviations in the 6–27% range, while the variation
between repetitions was between 2 and 18%, demonstrating good reproducibility.
This report is the first prediction of the retention time of cells
in iEK systems
Separation of Cells and Microparticles in Insulator-Based Electrokinetic Systems
Presented
here is the first continuous separation of microparticles
and cells of similar characteristics employing linear and nonlinear
electrokinetic phenomena in an insulator-based electrokinetic (iEK)
system. By utilizing devices with insulating features, which distort
the electric field distribution, it is possible to combine linear
and nonlinear EK phenomena, resulting in highly effective separation
schemes that leverage the new advancements in nonlinear electrophoresis.
This work combines mathematical modeling and experimentation to separate
four distinct binary mixtures of particles and cells. A computational
model with COMSOL Multiphysics was used to predict the retention times
(tR,p) of the particles and cells in iEK
devices. Then, the experimental separations were carried out using
the conditions identified with the model, where the experimental retention
time (tR,e) of the particles and cells
was measured. A total of four distinct separations of binary mixtures
were performed by increasing the level of difficulty. For the first
separation, two types of polystyrene microparticles, selected to mimic Escherichia coli and Saccharomyces
cerevisiae cells, were separated. By leveraging the
knowledge gathered from the first separation, a mixture of cells of
distinct domains and significant size differences, E. coli and S. cerevisiae, was successfully separated. The third separation also featured
cells of different domains but closer in size: Bacillus
cereus versus S. cerevisiae. The last separation included cells in the same domain and genus, B. cereus versus Bacillus subtilis. Separation results were evaluated in terms of number of plates
(N) and separation resolution (Rs), where Rs values for all
separations were above 1.5, illustrating complete separations. Experimental
results were in agreement with modeling results in terms of retention
times, with deviations in the 6–27% range, while the variation
between repetitions was between 2 and 18%, demonstrating good reproducibility.
This report is the first prediction of the retention time of cells
in iEK systems