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Nanomechanical properties of MscL α helices: A steered molecular dynamics study
, Article Channels ; Volume 11, Issue 3 , 2017 , Pages 209-223 ; 19336950 (ISSN) ; Bavi, O ; Vossoughi, M ; Naghdabadi, R ; Hill, A. P ; Martinac, B ; Jamali, Y ; Sharif University of Technology
Taylor and Francis Inc
2017
Abstract
Gating of mechanosensitive (MS) channels is driven by a hierarchical cascade of movements and deformations of transmembrane helices in response to bilayer tension. Determining the intrinsic mechanical properties of the individual transmembrane helices is therefore central to understanding the intricacies of the gating mechanism of MS channels. We used a constant-force steered molecular dynamics (SMD) approach to perform unidirectional pulling tests on all the helices of MscL in M. tuberculosis and E. coli homologs. Using this method, we could overcome the issues encountered with the commonly used constant-velocity SMD simulations, such as low mechanical stability of the helix during...
Challenges and future prospects for the delivery of biologics: oral mucosal, pulmonary, and transdermal routes
, Article AAPS Journal ; Volume 19, Issue 3 , 2017 , Pages 652-668 ; 15507416 (ISSN) ; Fathe, K. R ; Brunaugh, A ; Ferrati, S ; Li, S ; Montenegro Nicolini, M ; Mousavikhamene, Z ; McConville, J. T ; Prausnitz, M. R ; Smyth, H. D. C ; Sharif University of Technology
Springer New York LLC
2017
Abstract
Biologic products are large molecules such as proteins, peptides, nucleic acids, etc., which have already produced many new drugs for clinical use in the last decades. Due to the inherent challenges faced by biologics after oral administration (e.g., acidic stomach pH, digestive enzymes, and limited permeation through the gastrointestinal tract), several alternative routes of administration have been investigated to enable sufficient drug absorption into systemic circulation. This review describes the buccal, sublingual, pulmonary, and transdermal routes of administration for biologics with relevant details of the respective barriers. While all these routes avoid transit through the...
Two schemes for production of biosurfactant from Pseudomonas aeruginosa MR01: Applying residues from soybean oil industry and silica sol–gel immobilized cells
, Article Colloids and Surfaces B: Biointerfaces ; Volume 152 , 2017 , Pages 159-168 ; 09277765 (ISSN) ; Ebadipour, N ; Roostaazad, R ; Partovi, M ; Bahmaei, M ; Sharif University of Technology
Elsevier B.V
2017
Abstract
Rhamnolipids are the most common biosurfactants and P. aeruginosa strains are the most frequently studied microorganisms for the production of rhamnolipids. Eco-friendly advantages and promising applications of rhamnolipids in various industries are the major reasons for pursuing the economic production of these biosurfactants. This study shows that cultivation of P. aeruginosa MR01 in medium contained inexpensive soybean oil refinery wastes which exhibited similar levels and homologues of rhamnolipids. Mass spectrometry indicated that the Rha-C10-C10 and Rha-Rha-C10-C10 constitute the main rhamnolipids in different cultures of MR01 including one of oil carbon source analogues. Moreover,...
Urine concentrating mechanism modelling in rat kidney inner medulla
, Article 2016 23rd Iranian Conference on Biomedical Engineering and 2016 1st International Iranian Conference on Biomedical Engineering, ICBME 2016, 23 November 2016 through 25 November 2016 ; 2017 , Pages 111-116 ; 9781509034529 (ISBN) ; Saidi, M. S ; Banazadeh, M. H ; Sharif University of Technology
Abstract
Physicians use charts that are prepared by experiments on animals or humans to prescribe drug dosage for patients. This method requires some precious amount of time by the Ministry of Health to approve new drugs to be used in healthcare centers. Three-dimensional modeling of the inner medulla by considering the known physiological features help us to predict the distribution of a drug or any minerals in the kidney. In this study we present modeling of the important species distribution including Na+ and urea in the rat inner medulla that influence the urine concentrating mechanism. We use a C++ code to develop the inner medulla geometry based on physiological data to better capture the...
Meta-aligner: long-read alignment based on genome statistics
, Article BMC Bioinformatics ; Volume 18, Issue 1 , 2017 ; 14712105 (ISSN) ; Aliyari, A ; Ahmadian Moghadam, A ; Edrisi, M. A ; Motahari, S. A ; Khalaj, B. H ; Sharif University of Technology
Abstract
Background: Current development of sequencing technologies is towards generating longer and noisier reads. Evidently, accurate alignment of these reads play an important role in any downstream analysis. Similarly, reducing the overall cost of sequencing is related to the time consumption of the aligner. The tradeoff between accuracy and speed is the main challenge in designing long read aligners. Results: We propose Meta-aligner which aligns long and very long reads to the reference genome very efficiently and accurately. Meta-aligner incorporates available short/long aligners as subcomponents and uses statistics from the reference genome to increase the performance. Meta-aligner estimates...
Apoptotic and anti-apoptotic genes transcripts patterns of graphene in mice
, Article Materials Science and Engineering C ; Volume 71 , 2017 , Pages 460-464 ; 09284931 (ISSN) ; Hashemi, E ; Akhavan, O ; Shamsara, M ; Hashemi, M ; Farmany, A ; Daliri Joupari, M ; Sharif University of Technology
Elsevier Ltd
2017
Abstract
Recent studies showed that a large amount of graphene oxide accumulated in kidney and liver when it injected intravenously. Evaluation of lethal and apoptosis gene expression in these tissues, which are under stress is very important. In this paper the in vivo dose-dependent effects of graphene oxide and reduced graphene oxide nanoplatelets on kidney and liver of mice were studied. Balb/C mice were treated by 20 mg/kg body weight of nanoplatelets. Molecular biology analysis showed that graphene nanoplatelets injected intravenously lead to overexpression of BAX gene in both kidney and liver tissues (P ≥ 0.01). In addition these nanoparticles significantly increase BCL2 gene expression in both...
Theoretical modeling of actin-retrograde-flow passing clusters of confined T cell receptors
, Article Mathematical Biosciences ; Volume 283 , 2017 , Pages 1-6 ; 00255564 (ISSN) ; Firoozabadi, B ; Saidi, M. S ; Sharif University of Technology
Elsevier Inc
2017
Abstract
Through the activation process of T cells, actin filaments move from the cell periphery toward the cell center. The moving filaments engage with T cell receptors and thus contribute to transportation of the signaling molecules. To study the connection between the moving actin filaments and T cell receptors, an experiment available in the literature has measured filaments flow velocity passing over a region of confined clusters of receptors. It shows that flow velocity decreases in the proximity of the receptors, and then regains its normal value after traversing the region, suggesting a dissipative friction-like connection. In this work, we develop a minimal theoretical model to re-examine...
Short-term effects of particle size fractions on circulating biomarkers of inflammation in a panel of elderly subjects and healthy young adults
, Article Environmental Pollution ; Volume 223 , 2017 , Pages 695-704 ; 02697491 (ISSN) ; Naddafi, K ; Kashani, H ; Faridi, S ; Kunzli, N ; Nabizadeh, R ; Momeniha, F ; Gholampour, A ; Arhami, M ; Zare, A ; Pourpak, Z ; Hoseini, M ; Yunesian, M ; Sharif University of Technology
Abstract
Systemic inflammation biomarkers have been associated with risk of cardiovascular morbidity and mortality. We aimed to clarify associations of acute exposure to particulate matter (PM10(PM < 10 μm), PM2.5-10(PM 2.5–10 μm), PM2.5(PM < 2.5 μm), PM1-2.5(PM 1–2.5 μm), and PM1 (PM < 1 μm)) with systemic inflammation using panels of elderly subjects and healthy young adults. We followed a panel of 44 nonsmoking elderly subjects living in a retirement home and a panel of 40 healthy young adults living in a school dormitory in Tehran city, Iran from May 2012 to May 2013. Blood biomarkers were measured one every 7–8 weeks and included white blood cells (WBC), high sensitive C-reactive protein...
Cell shape affects nanoparticle uptake and toxicity: An overlooked factor at the nanobio interfaces
, Article Journal of Colloid and Interface Science ; Volume 531 , 2018 , Pages 245-252 ; 00219797 (ISSN) ; Ghahremani, M. H ; Hashemi, F ; Hormozi Nezhad, M. R ; Raoufi, M ; Zanganeh, S ; Atyabi, F ; Dinarvand, R ; Mahmoudi, M ; Sharif University of Technology
Academic Press Inc
2018
Abstract
Hypothesis: It is now being increasingly accepted that cells in their native tissue show different morphologies than those grown on a culture plate. Culturing cells on the conventional two-dimensional (2D) culture plates does not closely resemble the in vivo three-dimensional (3D) structure of cells which in turn seems to affect cellular function. This is one of the reasons, among many others, that nanoparticles uptake and toxicology data from 2D culture plates and in vivo environments are not correlated with one another. In this study, we offer a novel platform technology for producing more in vivo-like models of in vitro cell culture. Experiments: The normal fibroblast cells (HU02) were...
Magnetic carbon nanotubes: preparation, physical properties, and applications in biomedicine
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 46, Issue 7 , 2018 , Pages 1314-1330 ; 21691401 (ISSN) ; Farshbaf, M ; Annabi, N ; Kavetskyy, T ; Khalilov, R ; Saghfi, S ; Akbarzadeh, A ; Mousavi, S ; Sharif University of Technology
Abstract
Magnetic carbon nanotubes (MCNTs) have been widely studied for their potential applications in medicine, diagnosis, cell biology, analytical chemistry, and environmental technology. Introduction of MCNTs paved the way for the emergence of new approaches in nanobiotechnology and biomedicine as a result of their multifarious properties embedded within either the carbon nanotubes (CNTs) or magnetic parts. Numerous preparation techniques exists for functionalizing CNTs with magnetic nanoparticles, and these versatile strategies lay the ground for the generation of novel and versatile systems which are applicable to many industries and biological areas. Here, we review and discuss the recent...
Development of a novel nano-sized anti-VEGFA nanobody with enhanced physicochemical and pharmacokinetic properties
, Article Artificial Cells, Nanomedicine and Biotechnology ; Volume 46, Issue 7 , 2018 , Pages 1402-1414 ; 21691401 (ISSN) ; Norouzian, D ; Vaziri, B ; Ahangari Cohan, R ; Sardari, S ; Mahboudi, F ; Behdani, M ; Mansouri, K ; Mehdizadeh, A ; Sharif University of Technology
Abstract
Since physiological and pathological processes occur at nano-environments, nanotechnology has considered as an efficient tool for designing of next generation specific biomolecules with enhanced pharmacodynamic and pharmacodynamic properties. In the current investigation, by control of the size and hydrodynamic volume at the nanoscale, for the first time, physicochemical and pharmacokinetic properties of an anti-VEGFA nanobody was remarkably improved by attachment of a Proline-Alanine-Serine (PAS) rich sequence. The results elucidated unexpected impressive effects of PAS sequence on physicochemical properties especially on size, hydrodynamics radius, and even solubility of nanobody. CD...
Smart liposomal drug delivery for treatment of oxidative stress model in human embryonic stem cell-derived retinal pigment epithelial cells
, Article International Journal of Pharmaceutics ; Volume 548, Issue 1 , 2018 , Pages 62-72 ; 03785173 (ISSN) ; Abdkhodaie, M. J ; Sadeghi Abandansari, H ; Satarian, L ; Kazemi Ashtiani, M ; Jaafari, M. R ; Baharvand, H ; Sharif University of Technology
Abstract
Oxidative stress has been implicated in the progression of age-related macular degeneration (AMD). Treatment with antioxidants seems to delay progression of AMD. In this study, we suggested an antioxidant delivery system based on redox-sensitive liposome composed of phospholipids and a diselenide centered alkyl chain. Dynamic light scattering assessment indicated that the liposomes had an average size of 140 nm with a polydispersity index below 0.2. The percentage of encapsulation efficiency of the liposomes was calculated by high-performance liquid chromatography. The carriers were loaded with N-acetyl cysteine as a model antioxidant drug. We demonstrated responsiveness of the nanocarrier...
Genome annotation and comparative genomic analysis of Bacillus subtilis MJ01, a new bio-degradation strain isolated from oil-contaminated soil
, Article Functional and Integrative Genomics ; Volume 18, Issue 5 , 2018 , Pages 533-543 ; 1438793X (ISSN) ; Niazi, A ; Deihimi, T ; Taghavi, S. M ; Ayatollahi, S ; Ebrahimie, E ; Sharif University of Technology
Springer Verlag
2018
Abstract
One of the main challenges in elimination of oil contamination from polluted environments is improvement of biodegradation by highly efficient microorganisms. Bacillus subtilis MJ01 has been evaluated as a new resource for producing biosurfactant compounds. This bacterium, which produces surfactin, is able to enhance bio-accessibility to oil hydrocarbons in contaminated soils. The genome of B. subtilis MJ01 was sequenced and assembled by PacBio RS sequencing technology. One big contig with a length of 4,108,293 bp without any gap was assembled. Genome annotation and prediction of gene showed that MJ01 genome is very similar to B. subtilis spizizenii TU-B-10 (95% similarity). The comparison...
Design and parameter study of integrated microfluidic platform for CTC isolation and enquiry; a numerical approach
, Article Biosensors ; Volume 8, Issue 2 , 18 June , 2018 ; 20796374 (ISSN) ; Ahmad, S ; Momeni, M ; Sharif University of Technology
2018
Abstract
Being the second cause of mortality across the globe, there is now a persistent effort to establish new cancer medication and therapies. Any accomplishment in treating cancers entails the existence of accurate identification systems empowering the early diagnosis. Recent studies indicate CTCs’ potential in cancer prognosis as well as therapy monitoring. The chief shortcoming with CTCs is that they are exceedingly rare cells in their clinically relevant concentration. Here, we simulated a microfluidic construct devised for immunomagnetic separation of the particles of interest from the background cells. This separation unit is integrated with a mixer subunit. The mixer is envisioned for...
Effect of graphene oxide nanosheets on visible light-assisted antibacterial activity of vertically-aligned copper oxide nanowire arrays
, Article Journal of Colloid and Interface Science ; Volume 521 , 2018 , Pages 119-131 ; 00219797 (ISSN) ; Ashari Astani, N ; Rahighi, R ; Tayyebi, A ; Tayebi, M ; Khezri, J ; Hashemi, E ; Rothlisberger, U ; Simchi, A ; Sharif University of Technology
Academic Press Inc
2018
Abstract
In the present work, the effect of graphene oxide (GO) nanosheets on the antibacterial activity of CuO nanowire arrays under visible light irradiation is shown. A combined thermal oxidation/electrophoretic deposition technique was employed to prepare three-dimensional networks of graphene oxide nanosheets hybridized with vertically aligned CuO nanowires. With the help of standard antibacterial assays and X-ray photoelectron spectroscopy, it is shown that the light-activated antibacterial response of the hybrid material against gram-negative Escherichia coli is significantly improved as the oxide functional groups of the GO nanosheets are reduced. In order to explore the physicochemical...
Chemometrics comparison of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry Daphnia magna metabolic profiles exposed to salinity
, Article Journal of Separation Science ; Volume 41, Issue 11 , 2018 , Pages 2368-2379 ; 16159306 (ISSN) ; Garreta Lara, E ; Campos, B ; Barata, C ; Lacorte, S ; Tauler, R ; Sharif University of Technology
Wiley-VCH Verlag
2018
Abstract
The performances of gas chromatography with mass spectrometry and of comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry are examined through the comparison of Daphnia magna metabolic profiles. Gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with mass spectrometry were used to compare the concentration changes of metabolites under saline conditions. In this regard, a chemometric strategy based on wavelet compression and multivariate curve resolution–alternating least squares is used to compare the performances of gas chromatography with mass spectrometry and comprehensive two-dimensional gas chromatography with...
Novel microwave-assisted synthesis of porous g-C3N4/SnO2 nanocomposite for solar water-splitting
, Article Applied Surface Science ; Volume 440 , 15 May , 2018 , Pages 153-161 ; 01694332 (ISSN) ; Soleimani, F ; Naseri, N ; Soltaninejad, M ; Montazeri, S.M ; Sadrnezhaad, S.K ; Mohammadi, M.R ; Moghadam, H.A ; Forouzandeh, M ; Amin, M.H ; Sharif University of Technology
Elsevier B.V
2018
Abstract
Highly porous nanocomposites of graphitic-carbon nitride and tin oxide (g-C3N4/SnO2) were prepared through simple pyrolysis of urea molecules under microwave irradiation. The initial amount of tin was varied in order to investigate the effect of SnO2 content on preparation and properties of the composites. The synthesized nanocomposites were well-characterized by XRD, FE-SEM, HR-TEM, BET, FTIR, XPS, DRS, and PL. A homogeneous distribution of SnO2 nanoparticles with the size of less than 10 nm on the porous C3N4 sheets could be obtained, suggesting that in-situ synthesis of SnO2 nanoparticles was responsible for the formation of g-C3N4. The process likely occurred by the aid of the large...
Modeling, simulation, and employing dilution–dialysis microfluidic chip (DDMC) for heightening proteins refolding efficiency
, Article Bioprocess and Biosystems Engineering ; Volume 41, Issue 5 , 2018 , Pages 707-714 ; 16157591 (ISSN) ; Masoudi, M. M ; Shamloo, A ; Habibi Rezaei, M ; Moosavi Movahedi, A. A ; Sharif University of Technology
Springer Verlag
2018
Abstract
Miniaturized systems based on the principles of microfluidics are widely used in various fields, such as biochemical and biomedical applications. Systematic design processes are demanded the proper use of these microfluidic devices based on mathematical simulations. Aggregated proteins (e.g., inclusion bodies) in solution with chaotropic agents (such as urea) at high concentration in combination with reducing agents are denatured. Refolding methods to achieve the native proteins from inclusion bodies of recombinant protein relying on denaturant dilution or dialysis approaches for suppressing protein aggregation is very important in the industrial field. In this paper, a modeling approach is...
Construction of scaffolds composed of acellular cardiac extracellular matrix for myocardial tissue engineering
, Article Biologicals ; Volume 53 , 2018 , Pages 10-18 ; 10451056 (ISSN) ; Mashayekhan, S ; Ghanbari Asl, S ; Hajebrahimi, Z ; Sharif University of Technology
Academic Press
2018
Abstract
High rates of mortality and morbidity stemming from cardiovascular diseases unveil extreme limitations in current therapies despite enormous advances in medical and pharmaceutical sciences. Following myocardial infarction (MI), parts of myocardium undergo irreversible remodeling and is substituted by a scar tissue which eventually leads to heart failure (HF). To address this issue, cardiac patches have been utilized to initiate myocardial regeneration. In this study, a porous cardiac patch is fabricated using a mixture of decellularized myocardium extracellular matrix (ECM) and chitosan (CS). Results of rheological measurements, SEM, biodegradation test, and MTT assay showed that the...
Molecular dynamics simulations of orai reveal how the third transmembrane segment contributes to hydration and ca2+ selectivity in calcium release-activated calcium channels
, Article Journal of Physical Chemistry B ; Volume 122, Issue 16 , 2018 , Pages 4407-4417 ; 15206106 (ISSN) ; Berti, C ; Ejtehadi, M. R ; Furini, S ; Sharif University of Technology
American Chemical Society
2018
Abstract
Calcium release-activated calcium (CRAC) channels open upon depletion of Ca2+ from the endoplasmic reticulum, and when open, they are permeable to a selective flux of calcium ions. The atomic structure of Orai, the pore domain of CRAC channels, from Drosophila melanogaster has revealed many details about conduction and selectivity in this family of ion channels. However, it is still unclear how residues on the third transmembrane helix can affect the conduction properties of the channel. Here, molecular dynamics and Brownian dynamics simulations were employed to analyze how a conserved glutamate residue on the third transmembrane helix (E262) contributes to selectivity. The comparison...