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Whole cell mechanical property characterization based on mechanical properties of its cytoplasm and bio membrane
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 9 November 2012 through 15 November 2012 ; Volume 2 , November , 2012 , Pages 545-551 ; 9780791845189 (ISBN) ; Ahmadian, M. T ; Sharif University of Technology
2012
Abstract
Analysis and investigation of the relation between different parts of biological cells such as biomembrane, cytoplasm and nucleus can help to better understand their behaviors and material properties. In this paper, first, the whole elastic properties of mouse oocyte and embryo cells have been computed by inverse finite element and Levenberg-Marquardt optimization algorithm and second, using the derived mechanical properties and the mechanical properties of its bio membrane from the literature, the mechanical properties of its cytoplasm has been characterized. It has been assumed that the cell behavior is as continues, isotropic, nonlinear and homogenous material for modeling. Matching the...
Prediction of reaction force on external indenter in cell injection experiment using support vector machine technique
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE) ; Volume 2 , 2012 , Pages 537-543 ; 9780791845189 (ISBN) ; Ahmadian, M. T ; Sharif University of Technology
2012
Abstract
Evaluation of the reaction force on a tool which is used for exertion of force on biomaterials such as biological cells or soft tissues has applications in virtual reality based medical simulators or haptic tools. In this study, two least square based support vector machine (SVM) models have been constructed to predict the indentation or reaction force on mouse oocyte and embryo cells in cell injection experiment. Inputs of these two models are geometrical parameters of indented cell, namely dimple radius (a), dimple depth (w) and radius of the semicircular curve (R). Experimental data for calibration and prediction of the models have been captured from literatures. The performance of the...
Comparison of mouse embryo deformation modeling under needle injection using analytical Jacobian, nonlinear least square and artificial neural network techniques
, Article Scientia Iranica ; Volume 18, Issue 6 , 2011 , Pages 1486-1491 ; 10263098 (ISSN) ; Ahmadian, M. T ; Vossoughi, G. R ; Sharif University of Technology
Abstract
Analytical Jacobian, nonlinear least square and three layer artificial neural network models are employed to predict deformation of mouse embryos under needle injection, based on experimental data captured from literature. The Maximum Absolute Error (MAE), coefficient of determination ( R2), Relative Error of Prediction (REP), Root Mean Square Error of Prediction (RMSEP), NashSutcliffe coefficient of efficiency ( Ef) and accuracy factor ( Af) are used as the basis for comparison of these three models. Analytical Jacobian, nonlinear least square and ANN models have yielded the correlation coefficient of 0.9985, 0.9964 and 0.9998, respectively. The REP between the models predicted values and...
Deformation prediction of mouse embryos in cell injection experiment by a feedforward artificial neural network
, Article Proceedings of the ASME Design Engineering Technical Conference, 28 August 2011 through 31 August 2011 ; Volume 2, Issue PARTS A AND B , August , 2011 , Pages 543-550 ; 9780791854792 (ISBN) ; Ahmadian, M. T ; Vossoughi, G. R ; Sharif University of Technology
2011
Abstract
In this study, neural network models have been used to predict the mechanical behaviors of mouse embryos. In addition, sensitivity analysis has been carried out to investigate the influence of the significance of input parameters on the mechanical behavior of mouse embryos. In order to reach these purposes two neural network models have been implemented. Experimental data earlier deduced-by [Flückiger, M. (2004). Cell Membrane Mechanical Modeling for Microrobotic Cell Manipulation. Diploma Thesis, ETHZ Swiss Federal Institute of Technology, Zurich, WS03/04]-were collected to obtain training and test data for the neural network. The results of these investigations show that the correlation...
Application of hyperelastic models in mechanical properties prediction of mouse oocyte and embryo cells at large deformations
, Article Scientia Iranica ; Volume 25, Issue 2B , March , 2018 , Pages 700-710 ; 10263098 (ISSN) ; Ahmadian, M. T ; Alizadeh, A ; Tarighi, S ; Sharif University of Technology
Sharif University of Technology
2018
Abstract
Biological cell studies have many applications in biology, cell manipulation, and diagnosis of diseases such as cancer and malaria. In this study, Inverse Finite Element Method (IFEM) combined with Levenberg-Marquardt optimization algorithm has been used to extract and characterize material properties of mouse oocyte and embryo cells at large deformations. Then, the simulation results have been validated using data from experimental works. In this study, it is assumed that cell material is hyperelastic, isotropic, homogenous, and axisymmetric. For inverse analysis, FEM model of cell injection experiment implemented in Abaqus software has been coupled with Levenberg-Marquardt optimization...
Effect of formulation factors on the bioactivity of glucose oxidase encapsulated chitosan-alginate microspheres: In vitro investigation and mathematical model prediction
, Article Chemical Engineering Science ; Volume 125 , March , 2015 , Pages 4-12 ; 00092509 (ISSN) ; Cheng, J ; Wu, X. Y ; Sharif University of Technology
Elsevier Ltd
2015
Abstract
Higher reactive oxygen species (ROS) levels in cancer cells than normal cells have long been recognized, which makes cancer cells more susceptible to excess ROS. Thus oxidation (also called pro-oxidant) therapy has been explored as new cancer therapy regimens. To produce additional ROS, e.g. H2O2 in situ within tumor, we encapsulated glucose oxidase in chitosan-coated alginate-calcium microspheres (GOX-MS) for locoregional treatment and demonstrated its efficacy against cancer cells in vitro and in vivo. Owing to the complex biological functions of ROS, the production rate and amount of H2O2 are critical to achieve therapeutic benefits without causing normal tissue toxicity. This work was...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and PVA hydrogel
, Article Advanced Materials Technologies ; 2021 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2021
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Biomimetic ultraflexible piezoresistive flow sensor based on graphene nanosheets and pva hydrogel
, Article Advanced Materials Technologies ; Volume 7, Issue 1 , 2022 ; 2365709X (ISSN) ; Moradi, H ; Wu, S ; Han, Z. J ; Razmjou, A ; Asadnia, M ; Sharif University of Technology
John Wiley and Sons Inc
2022
Abstract
Flow sensors play a critical role in monitoring flow parameters, including rate, velocity, direction, and rotation frequency. In this paper, inspired by biological hair cells in the human vestibular system, an innovative flow sensor is developed based on polyvinyl alcohol (PVA) hydrogel nanocomposites with a maze-like network of vertically grown graphene nanosheets (VGNs). The VGNs/PVA hydrogel absorbs a copious amount of water when immersed in water, making the sensor highly sensitive to tiny stimuli underwater. The sensor demonstrates a high sensitivity (5.755 mV (mm s−1)−1) and extremely low velocity detection (0.022 mm s−1). It also reveals outstanding performance in detecting...
Preparation and characterization of multi-walled carbon nanotube/hydroxyapatite nanocomposite film dip coated on Ti-6Al-4V by sol-gel method for biomedical applications: An in vitro study
, Article Materials Science and Engineering C ; Volume 33, Issue 4 , 2013 , Pages 2002-2010 ; 09284931 (ISSN) ; Hooshmand, T ; Mohammadi, M ; Najafi, F ; Sharif University of Technology
2013
Abstract
In the present research, the introduction of multi-walled carbon nanotubes (MWCNTs) into the hydroxyapatite (HA) matrix and dip coating of nanocomposite on titanium alloy (Ti-6Al-4V) plate was conducted in order to improve the performance of the HA-coated implant via the sol-gel method. The structural characterization and electron microscopy results confirmed well crystallized HA-MWCNT coating and homogenous dispersion of carbon nanotubes in the ceramic matrix at temperatures as low as 500 C. The evaluation of the mechanical properties of HA and HA/MWCNT composite coatings with different weight percentages of MWCNTs showed that the addition of low concentrations of MWCNTs (0.5 and 1 wt.%)...
Computational study of geometric effects of bottom wall microgrooves on cell docking inside microfluidic devices
, Article Journal of Mechanics in Medicine and Biology ; Volume 21, Issue 2 , 2021 ; 02195194 (ISSN) ; Saadatmand, M ; Sharif University of Technology
World Scientific
2021
Abstract
Cells docking inside microfluidic devices is effective in studying cell biology, cell-based biosensing, as well as drug screening. Furthermore, single cell and regularly cells docking inside the microstructure of microfluidic systems are advantageous in different analyses of single cells exposed to equal drug concentration and mechanical stimulus. In this study, we investigated bottom wall microgrooves with semicircular and rectangular geometries with different sizes which are suitable for single cell docking along the length of the microgroove in x-direction and numerous cells docking regularly in one line inside the microgroove in a 3D microchannel. We used computational fluid dynamics to...
Computational study of geometric effects of bottom wall microgrooves on cell docking inside microfluidic devices
, Article Journal of Mechanics in Medicine and Biology ; Volume 21, Issue 2 , 2021 ; 02195194 (ISSN) ; Saadatmand, M ; Sharif University of Technology
World Scientific
2021
Abstract
Cells docking inside microfluidic devices is effective in studying cell biology, cell-based biosensing, as well as drug screening. Furthermore, single cell and regularly cells docking inside the microstructure of microfluidic systems are advantageous in different analyses of single cells exposed to equal drug concentration and mechanical stimulus. In this study, we investigated bottom wall microgrooves with semicircular and rectangular geometries with different sizes which are suitable for single cell docking along the length of the microgroove in x-direction and numerous cells docking regularly in one line inside the microgroove in a 3D microchannel. We used computational fluid dynamics to...
Development of ultrasensitive biomimetic auditory hair cells based on piezoresistive hydrogel nanocomposites
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 37 , 2021 , Pages 44904-44915 ; 19448244 (ISSN) ; Moradi, H ; Pastras, C. J ; Abolpour Moshizi, S ; Wu, S ; Asadnia, M ; Sharif University of Technology
American Chemical Society
2021
Abstract
With an ageing population, hearing disorders are predicted to rise considerably in the following decades. Thus, developing a new class of artificial auditory system has been highlighted as one of the most exciting research topics for biomedical applications. Herein, a design of a biocompatible piezoresistive-based artificial hair cell sensor is presented consisting of a highly flexible and conductive polyvinyl alcohol (PVA) nanocomposite with vertical graphene nanosheets (VGNs). The bilayer hydrogel sensor demonstrates excellent performance to mimic biological hair cells, responding to acoustic stimuli in the audible range between 60 Hz to 20 kHz. The sensor output demonstrates stable...
Development of ultrasensitive biomimetic auditory hair cells based on piezoresistive hydrogel nanocomposites
, Article ACS Applied Materials and Interfaces ; Volume 13, Issue 37 , 2021 , Pages 44904-44915 ; 19448244 (ISSN) ; Moradi, H ; Pastras, C. J ; Abolpour Moshizi, S ; Wu, S ; Asadnia, M ; Sharif University of Technology
American Chemical Society
2021
Abstract
With an ageing population, hearing disorders are predicted to rise considerably in the following decades. Thus, developing a new class of artificial auditory system has been highlighted as one of the most exciting research topics for biomedical applications. Herein, a design of a biocompatible piezoresistive-based artificial hair cell sensor is presented consisting of a highly flexible and conductive polyvinyl alcohol (PVA) nanocomposite with vertical graphene nanosheets (VGNs). The bilayer hydrogel sensor demonstrates excellent performance to mimic biological hair cells, responding to acoustic stimuli in the audible range between 60 Hz to 20 kHz. The sensor output demonstrates stable...
Simulation of Red Blood Cell mechanical behavior in optical tweezers experiment based on a particle method
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 2 , 2010 , Pages 325-329 ; 9780791844267 (ISBN) ; Firoozbakhsh, K ; Hasanian, M
Abstract
Optical tweezers provide an accurate measurement technique for evaluating mechanical properties of the living cells and many experimental studies have been done to understand the behavior of cells due to external forces. Numerical studies such as finite element methods have been used in order to simulate mechanical behavior of the Red Blood Cells (RBCs). Recent studies have shown that the particle methods are useful tools to simulate the mechanical behavior of living cells. Since in microscopic scales, using discrete models are preferred than continuum methods, a particle-based method is used to simulate the deformation of RBC which is stretched by optical tweezers. The cytoplasm of RBC is...
Modeling of cell deformation under external force using artificial neural network
, Article ASME International Mechanical Engineering Congress and Exposition, Proceedings (IMECE), 12 November 2010 through 18 November 2010 ; Volume 2 , 2010 , Pages 659-665 ; 9780791844267 (ISBN) ; Vossoughi, G. R ; Abbasi, A. A ; Raeissi, P ; Sharif University of Technology
Abstract
Embryogenesis, regeneration and cell differentiation in microbiological entities are influenced by mechanical forces. Therefore, development of mechanical properties of these materials is important. Neural network technique is a useful method which can be used to obtain cell deformation by the means of force-geometric deformation data or vice versa. Prior to insertion in the needle injection process, deformation and geometry of cell under external point-load is a key element to understand the interaction between cell and needle. In this paper the goal is the prediction of cell membrane deformation under a certain force, and to visually estimate the force of indentation on the membrane from...
The influence of the female reproductive tract and sperm features on the design of microfluidic sperm-sorting devices
, Article Journal of Assisted Reproduction and Genetics ; Volume 39, Issue 1 , 2022 , Pages 19-36 ; 10580468 (ISSN) ; Hosseini, M ; Saadatmand, M ; Abbaspourrad, A ; Sharif University of Technology
Springer
2022
Abstract
Although medical advancements have successfully helped a lot of couples with their infertility by assisted reproductive technologies (ART), sperm selection, a crucial stage in ART, has remained challenging. Therefore, we aimed to investigate novel sperm separation methods, specifically microfluidic systems, as they do sperm selection based on sperm and/or the female reproductive tract (FRT) features without inflicting any damage to the selected sperm during the process. In this review, after an exhaustive studying of FRT features, which can implement by microfluidics devices, the focus was centered on sperm selection and investigation devices. During this study, we tried not to only point to...
Differentiation of human neural stem cells into neural networks on graphene nanogrids
, Article Journal of Materials Chemistry B ; Volume 1, Issue 45 , 2013 , Pages 6291-6301 ; 20507518 (ISSN) ; Ghaderi, E ; Sharif University of Technology
2013
Abstract
Graphene nanogrids (crossed graphene nanoribbons synthesized by the oxidative unzipping of multi-walled carbon nanotubes) on a SiO2 matrix containing TiO2 nanoparticles (NPs) were applied as a photocatalytic stimulator in the accelerated differentiation of human neural stem cells (hNSCs) into two-dimensional neural networks. The hydrophilic graphene nanogrids exhibited patterned proliferations of hNSCs (consistent with patterns of the nanogrids), in contrast with the usual random growths occurring on quartz substrates. The number of cell nuclei differentiated on reduced graphene oxide nanoribbon (rGONR) grid/TiO2 NPs/SiO2 increased ∼5.9 and 26.8 fold compared to the number of cells on quartz...
Flash photo stimulation of human neural stem cells on graphene/TiO 2 heterojunction for differentiation into neurons
, Article Nanoscale ; Volume 5, Issue 21 , 2013 , Pages 10316-10326 ; 20403364 (ISSN) ; Ghaderi, E ; Sharif University of Technology
2013
Abstract
For the application of human neural stem cells (hNSCs) in neural regeneration and brain repair, it is necessary to stimulate hNSC differentiation towards neurons rather than glia. Due to the unique properties of graphene in stem cell differentiation, here we introduce reduced graphene oxide (rGO)/TiO2 heterojunction film as a biocompatible flash photo stimulator for effective differentiation of hNSCs into neurons. Using the stimulation, the number of cell nuclei on rGO/TiO2 increased by a factor of ∼1.5, while on GO/TiO2 and TiO2 it increased only ∼48 and 24%, respectively. Moreover, under optimum conditions of flash photo stimulation (10 mW cm-2 flash intensity and 15.0 mM ascorbic acid in...
Genotoxicity of graphene nanoribbons in human mesenchymal stem cells
, Article Carbon ; Volume 54 , 2013 , Pages 419-431 ; 00086223 (ISSN) ; Ghaderi, E ; Emamy, H ; Akhavan, F ; Sharif University of Technology
2013
Abstract
Single-layer reduced graphene oxide nanoribbons (rGONRs) were obtained through an oxidative unzipping of multi-walled carbon nanotubes and a subsequent deoxygenation by hydrazine and bovine serum albumin. Human mesenchymal stem cells (hMSCs) were isolated from umbilical cord blood and used for checking the concentration- and time-dependent cyto- and geno-toxic effects of the rGONRs and reduced graphene oxide sheets (rGOSs). The cell viability assay indicated significant cytotoxic effects of 10 μg/mL rGONRs after 1 h exposure time, while the rGOSs exhibited the same cytotoxicity at concentration of 100 μg/mL after 96 h. The oxidative stress was found as the main mechanism involved in the...