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    A study of Acidithiobacillus Ferrooxidans DSMZ 583 Adaptation to Heavy Metals

    , Article Iranian Journal of Biotechnology ; Volume 9, Issue 2 , 2011 , Pages 133-144 ; 17283043 (ISSN) Yaghmaei, S ; Ghobadi, Z ; Sharif University of Technology
    In this study the ability of Acidithiobacillus ferrooxi-dans, with regard to the biorecovery of heavy metals in shake flask has been investigated. Adaptation experiments with the single metal ions Ni, Co, V, Mo, W and a mixture of the first four metal ions in the medium was developed through serial sub-culturing. Adaptation showed that A. ferrooxidans could tolerate up to 2.3 g/l Ni, 1.4 g/l Co, 1.4 g/l V, 0.045 g/l Mo and 0.005 g/l W, singly. In the presence of multi-metals considering a mixture of Ni-Co-V-Mo, the bacteria was able to tolerate up to 1.5 g/l Ni, 0.8 g/l Co, 0.8 g/l V and 0.05 g/l Mo in steps of 50-100 mg/l for Ni, Co and V, while for Mo and W with increments in concentration... 

    Magnetic resonance imaging tracking of stem cells in vivo using iron oxide nanoparticles as a tool for the advancement of clinical regenerative medicine

    , Article Chemical Reviews ; Volume 111, Issue 2 , November , 2011 , Pages 253-280 ; 00092665 (ISSN) Mahmoudi, M ; Hosseinkhani, H ; Hosseinkhani, M ; Boutry, S ; Simchi, A ; Shane Journeay, W ; Subramani, K ; Laurent, S ; Sharif University of Technology
    Fetal stem cells, which can be isolated from the organs of fetuses, differentiate along multiple lineages. Their advantages over their adult counterparts include better intrinsic homing and engraftment and lower immunogenicity, and they are less ethically contentious. It is noteworthy that Mesenchymal Stem Cells (MSC) can be activated and mobilized at the site of damaged tissue. Since vascular delivery suffers from a pulmonary first pass effect, direct or systemic injection of MSCs into the damaged tissue is preferred, particularly in the case of versatile tissue ischemia. Ultrasound applies acoustic energy with a frequency above human hearing (20 kHz). Ultrasound imaging or sonography... 

    Structural stability and sustained release of protein from a multilayer nanofiber/nanoparticle composite

    , Article International Journal of Biological Macromolecules ; Volume 75 , April , 2015 , Pages 248-257 ; 01418130 (ISSN) Vakilian, S ; Mashayekhan, S ; Shabani, I ; Khorashadizadeh, M ; Fallah, A ; Soleimani, M ; Sharif University of Technology
    Elsevier  2015
    The cellular microenvironment can be engineered through the utilization of various nano-patterns and matrix-loaded bioactive molecules. In this study, a multilayer system of electrospun scaffold containing chitosan nanoparticles was introduced to overcome the common problems of instability and burst release of proteins from nanofibrous scaffolds. Bovine serum albumin (BSA)-loaded chitosan nanoparticles was fabricated based on ionic gelation interaction between chitosan and sodium tripolyphosphate. Suspension electrospinning was employed to fabricate poly-e{open}-caprolacton (PCL) containing protein-loaded chitosan nanoparticles with a core-shell structure. To obtain the desired scaffold... 

    Effect of various carbon sources on biomass and lipid production of Chlorella vulgaris during nutrient sufficient and nitrogen starvation conditions

    , Article Bioresource Technology ; Volume 180 , 2015 , Pages 311-317 ; 09608524 (ISSN) Abedini Najafabadi, H ; Malekzadeh, M ; Jalilian, F ; Vossoughi, M ; Pazuki, G ; Sharif University of Technology
    In this research, a two-stage process consisting of cultivation in nutrient rich and nitrogen starvation conditions was employed to enhance lipid production in Chlorella vulgaris algal biomass. The effect of supplying different organic and inorganic carbon sources on cultivation behavior was investigated. During nutrient sufficient condition (stage I), the highest biomass productivity of 0.158. ±. 0.011. g/L/d was achieved by using sodium bicarbonate followed by 0.130. ±. 0.013, 0.111. ±. 0.005 and 0.098. ±. 0.003. g/L/d for sodium acetate, carbon dioxide and molasses, respectively. Cultivation under nitrogen starvation process (stage II) indicated that the lipid and fatty acid content... 

    Controlled release of doxorubicin from electrospun PEO/chitosan/graphene oxide nanocomposite nanofibrous scaffolds

    , Article Materials Science and Engineering C ; Volume 48 , March , 2015 , Pages 384-390 ; 09284931 (ISSN) Ardeshirzadeh, B ; Aboutalebi Anaraki, N ; Irani, M ; Roshanfekr Rad, L ; Shamshiri, S ; Sharif University of Technology
    Elsevier Ltd  2015
    Polyethylene oxide (PEO)/chitosan (CS)/graphene oxide (GO) electrospun nanofibrous scaffolds were successfully developed via electrospinning process for controlled release of doxorubicin (DOX). The SEM analysis of nanofibrous scaffolds with different contents of GO (0.1, 0.2, 0.5 and 0.7 wt.%) indicated that the minimum diameter of nanofibers was found to be 85 nm for PEO/CS/GO 0.5% nanofibers. The π-π stacking interaction between DOX and GO with fine pores of nanofibrous scaffolds exhibited higher drug loading (98%) and controlled release of the DOX loaded PEO/CS/GO nanofibers. The results of DOX release from nanofibrous scaffolds at pH 5.3 and 7.4 indicated strong pH dependence. The... 

    Protein corona composition of gold nanoparticles/nanorods affects amyloid beta fibrillation process

    , Article Nanoscale ; Volume 7, Issue 11 , Feb , 2015 , Pages 5004-5013 ; 20403364 (ISSN) Mirsadeghi, S ; Dinarvand, R ; Ghahremani, M. H ; Hormozi-Nezhad, M. R ; Mahmoudi, Z ; Hajipour, M. J ; Atyabi, F ; Ghavami, M ; Mahmoudi, M ; Sharif University of Technology
    Royal Society of Chemistry  2015
    Protein fibrillation process (e.g., from amyloid beta (Aβ) and α-synuclein) is the main cause of several catastrophic neurodegenerative diseases such as Alzheimer's and Parkinson diseases. During the past few decades, nanoparticles (NPs) were recognized as one of the most promising tools for inhibiting the progress of the disease by controlling the fibrillation kinetic process; for instance, gold NPs have a strong capability to inhibit Aβ fibrillations. It is now well understood that a layer of biomolecules would cover the surface of NPs (so called "protein corona") upon the interaction of NPs with protein sources. Due to the fact that the biological species (e.g., cells and amyloidal... 

    Advances in skin regeneration: application of electrospun scaffolds

    , Article Advanced Healthcare Materials ; Volume 4, Issue 8 , 2015 , Pages 1114-1133 ; 21922640 (ISSN) Norouzi, M ; Boroujeni, S. M ; Omidvarkordshouli, N ; Soleimani, M ; Sharif University of Technology
    Wiley-VCH Verlag  2015
    The paucity of cellular and molecular signals essential for normal wound healing makes severe dermatological ulcers stubborn to heal. The novel strategies of skin regenerative treatments are focused on the development of biologically responsive scaffolds accompanied by cells and multiple biomolecules resembling structural and biochemical cues of the natural extracellular matrix (ECM). Electrospun nanofibrous scaffolds provide similar architecture to the ECM leading to enhancement of cell adhesion, proliferation, migration and neo tissue formation. This Review surveys the application of biocompatible natural, synthetic and composite polymers to fabricate electrospun scaffolds as skin... 

    A viscoelastic model for axonal microtubule rupture

    , Article Journal of Biomechanics ; Volume 48, Issue 7 , 2015 , Pages 1241-1247 ; 00219290 (ISSN) Shamloo, A ; Manuchehrfar, F ; Rafii Tabar, H ; Sharif University of Technology
    Elsevier Ltd  2015
    Axon is an important part of the neuronal cells and axonal microtubules are bundles in axons. In axons, microtubules are coated with microtubule-associated protein tau, a natively unfolded filamentous protein in the central nervous system. These proteins are responsible for cross-linking axonal microtubule bundles. Through complimentary dimerization with other tau proteins, bridges are formed between nearby microtubules creating bundles. Formation of bundles of microtubules causes their transverse reinforcement and has been shown to enhance their ability to bear compressive loads. Though microtubules are conventionally regarded as bearing compressive loads, in certain circumstances during... 

    Toxicity of graphene and graphene oxide nanowalls against bacteria

    , Article ACS Nano ; Volume 4, Issue 10 , October , 2010 , Pages 5731-5736 ; 19360851 (ISSN) Akhavan, O ; Ghaderi, E ; Sharif University of Technology
    Bacterial toxicity of graphene nanosheets in the form of graphene nanowalls deposited on stainless steel substrates was investigated for both Gram-positive and Gram-negative models of bacteria. The graphene oxide nanowalls were obtained by electrophoretic deposition of Mg2+-graphene oxide nanosheets synthesized by a chemical exfoliation method. On the basis of measuring the efflux of cytoplasmic materials of the bacteria, it was found that the cell membrane damage of the bacteria caused by direct contact of the bacteria with the extremely sharp edges of the nanowalls was the effective mechanism in the bacterial inactivation. In this regard, the Gram-negative Escherichia coli bacteria with an... 

    Optimizing fuzzy logic controller for diabetes type I by genetic algorithm

    , Article 2010 The 2nd International Conference on Computer and Automation Engineering, ICCAE 2010, 26 February 2010 through 28 February 2010, Singapore ; Volume 2 , 2010 , Pages 4-8 ; 9781424455850 (ISBN) Ghaemi Osgouie, K ; Azizi, A ; Sharif University of Technology
    Biological systems are highly nonlinear, and there is a significant amount of variability from one patient to another. A controller for drug infusion has to be able to achieve good performance for most of the potential patient population. These controllers are designed for the general population, as no knowledge is available before hand for each particular patient. This necessitates perforce an algorithm that will be able to compensate for the differences between individuals and external factors. Of the possibilities, fuzzy logic direct model reference adaptive control (DMRAC) is the choice for Insulin infusion control for diabetes type I as results presented herein. Safety and robustness... 

    In vitro release behavior and cytotoxicity of doxorubicin-loaded gold nanoparticles in cancerous cells

    , Article Biotechnology Letters ; Volume 32, Issue 5 , May , 2010 , Pages 649-654 ; 01415492 (ISSN) Asadishad, B ; Vossoughi, M ; Alamzadeh, I ; Sharif University of Technology
    Doxorubicin (DOX), a common cancer chemotherapeutics, was conjugated to folate-modified thiolated-polyethylene glycol-functionalized gold nanoparticles. The in vitro, controlled release behavior of DOX-loaded gold nanoparticles was observed using porous dialysis membranes (cut-off = 2 kDa). DOX-loaded gold nanoparticles had higher cytotoxicity for folate-receptor-positive cells (KB cells) compared to folate-receptor-negative cells (A549 cells) which were 48 and 62% viable for 10 μM doxorubicin, respectively. This indicates the potential of these nano-carriers for targeted-delivery. In addition, healthy cell viability was 69% for 10 μM free doxorubicin whereas for the same content of drug in... 

    Biodesulfurization of dibenzothiophene by a newly isolated Rhodococcus erythropolis strain

    , Article Bioresource Technology ; Volume 101, Issue 3 , 2010 , Pages 1102-1105 ; 09608524 (ISSN) Davoodi Dehaghani, F ; Vosoughi, M ; Ziaee, A. A ; Sharif University of Technology
    A new dibenzothiophene (DBT) desulfurizing bacterium was isolated from oil-contaminated soils in Iran. HPLC analysis and PCR-based detection of the presence of the DBT desulfurization genes (dszA, dszB and dszC) indicate that this strain converts DBT to 2-hydroxybiphenyl (2-HBP) via the 4S pathway. The strain, identified as Rhodococcus erythropolis SHT87, can utilize DBT, dibenzothiophene sulfone, thiophene, 2-methylthiophene and dimethylsulfoxide as a sole sulfur source for growth at 30 °C. The maximum specific desulfurization activity of strain SHT87 resting cells in aqueous and biphasic organic-aqueous systems at 30 °C was determined to be 0.36 and 0.47 μmol 2-HBP min-1 (g dry cell)-1,... 

    Use of the freely-swimming, Serratia marcescens bacteria to enhance mixing in microfluidic systems

    , Article ASME 2009 International Mechanical Engineering Congress and Exposition, 13 November 2009 through 19 November 2009 ; Volume 12, Issue PART A , 2010 , Pages 463-467 ; 9780791843857 (ISBN) Peysepar, M ; Shafii, M. B ; Rasoulian, R ; Jamalifar, H ; Fazeli, M. R ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME) 
    Mixing has become a challenge in micro-fluidic systems because of the low Reynolds number in micro-channels. The method which is implemented in this paper is to use freely-swimming bacteria to enhance the mixing process. Accordingly, the Serratia marcescens bacteria were used for this matter. The mixing performance of the system is quantified by measuring the diffusion rate of Rhodamine B in a particular section of a channel connected to a chamber with varying Rhodamine B concentration. The concentration of Rhodamine B was measured using the Laser Induced Fluorescence (LIF) technique. The channel is in the form of a pipe and is closed on the extending side. In this paper, it is demonstrated... 

    Specific targeting delivery to MUC1 overexpressing tumors by albumin-chitosan nanoparticles conjugated to DNA aptamer

    , Article International Journal of Pharmaceutics ; Volume 515, Issue 1-2 , 2016 , Pages 607-615 ; 03785173 (ISSN) Esfandyari Manesh, M ; Mohammadi, A ; Atyabi, F ; Nabavi, S. M ; Ebrahimi, S. M ; Shahmoradi, E ; Shiri Varnamkhasti, B ; Ghahremani, M. H ; Dinarvand, R ; Sharif University of Technology
    Elsevier B.V  2016
    Chitosan-coated human serum albumin nanoparticles were functionalized by MUC1 aptamer to obtain a selective drug carrier toward cancers overexpressing MUC1. The negative charges of albumin nanoparticles were shifted to positive charges by surface modification with chitosan, and MUC1 was conjugated through an acrylate spacer. The cytotoxicity of targeted nanoparticles was significantly more than non-aptamer nanoparticles, and also the chitosan-coated nanoparticles had more cytotoxic effects than the negatively charged albumin nanoparticles. The IC50 of targeted nanoparticles was 28 and 26% of free paclitaxel in MCF7 and T47D cells at 48 h, respectively. Confocal laser scanning electron... 

    Numerical modeling of ureagenesis in a microfluidic channel mimicking a liver lobule

    , Article 2015 22nd Iranian Conference on Biomedical Engineering, ICBME 2015, 25 November 2015 through 28 November 2015 ; 2015 , Pages 54-59 ; 9781467393515 (ISBN) Sharifi, F ; Firoozabadi, B ; Saidi, M. S ; Firoozbakhsh, K ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2015
    Ammonia detoxification is one of the main functions of the liver results in production of urea. In this study ammonia elimination and urea production was simulated in a microchannel mimicking the hepatic porto central axis. Navier- Stockes equations along with convection equations were solved for the related species in the entire domain. Since the Reynolds number was small (~1) the fluid flow regime was laminar. Urea cycle was modeled regarding its four main enzymes. Twelve rate equations were also solved in order to obtain the concentration of each metabolites participating in urea cycle. Concentration of the urea reached its maximum ca. 1.2e-5 M at the end of the channel which is in good... 

    Effects of short term and long term Extremely Low Frequency Magnetic Field on depressive disorder in mice: Involvement of nitric oxide pathway

    , Article Life Sciences ; Volume 146 , 2016 , Pages 52-57 ; 00243205 (ISSN) Madjid Ansari, A ; Farzam Pour, S ; Sadr, A ; Shekarchi, B ; Majid Zadeh, A. K ; Sharif University of Technology
    Elsevier Inc 
    Aims Previous reports on the possible effects of Extremely Low Frequency Magnetic Fields (ELF MF) on mood have been paradoxical in different settings while no study has yet been conducted on animal behavior. In addition, it was shown that ELF MF exposure makes an increase in brain nitric oxide level. Therefore, in the current study, we aimed to assess the possible effect(s) of ELF MF exposure on mice Forced Swimming Test (FST) and evaluate the probable role of the increased level of nitric oxide in the observed behavior. Main methods Male adult mice NMRI were recruited to investigate the short term and long term ELF MF exposure (0.5 mT and 50 Hz, single 2 h and 2 weeks 2 h a day). Locomotor... 

    Development of a novel method for determination of mercury based on its inhibitory effect on horseradish peroxidase activity followed by monitoring the surface plasmon resonance peak of gold nanoparticles

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Volume 153 , 2016 , Pages 709-713 ; 13861425 (ISSN) Khodaveisi, J ; Haji Shabani, A. M ; Dadfarnia, S ; Rohani Moghadam, M. R ; Hormozi Nezhad, M. R ; Sharif University of Technology
    A highly sensitive and simple indirect spectrophotometric method has been developed for the determination of trace amounts of inorganic mercury (Hg2 +) in aqueous media. The method is based on the inhibitory effect of Hg2 + on the activity of horseradish peroxidase (HRP) in the oxidation of ascorbic acid by hydrogen peroxide followed by the reduction of Au3 + to Au-NPs by unreacted ascorbic acid and the measurement of the absorbance of localized surface plasmon resonance (LSPR) peak of gold nanoparticles (at 530 nm) which is directly proportional to the concentration of Hg2 +. Under the optimum conditions, the calibration curve was linear in the concentration range of 1-220 ng mL- 1. Limits... 

    Inhibitory activity on type 2 diabetes and hypertension key-enzymes, and antioxidant capacity of veronica persica phenolic-rich extracts

    , Article Cellular and Molecular Biology ; Volume 62, Issue 6 , 2016 , Pages 80-85 ; 01455680 (ISSN) Sharifi Rad, M ; Tayeboon, G. S ; Sharifi Rad, J ; Iriti, M ; Varoni, E. M ; Razazi, S ; Sharif University of Technology
    Cellular and Molecular Biology Association  2016
    Veronica genus (Plantaginaceae) is broadly distributed in different habitats. In this study, the inhibitory activity of free soluble and conjugated phenolic extracts of Veronica persica on key enzymes associated to type 2 diabetes (α-glucosidase and α-amylase) and hypertension (angiotensin I converting enzyme, ACE) was assessed, as well as their antioxidant power. Our results showed that both the extracts inhibited α-amylase, α-glucosidase and ACE in a dose-dependent manner. In particular, free phenolic extract significantly (P < 0.05) inhibited α-glucosidase (IC50 532.97 μg/mL), whereas conjugated phenolic extract significantly (P < 0.05) inhibited a-amylase (IC50 489.73 μg/mL) and ACE... 

    Characterization of a microfluidic microbial fuel cell as a power generator based on a nickel electrode

    , Article Biosensors and Bioelectronics ; Volume 79 , 2016 , Pages 327-333 ; 09565663 (ISSN) Mardanpour, M. M ; Yaghmaei, S ; Sharif University of Technology
    Elsevier Ltd  2016
    This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104Wm-3 was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of... 

    The highest inhibition coefficient of phenol biodegradation using an acclimated mixed culture

    , Article Water Science and Technology ; Volume 73, Issue 5 , 2016 , Pages 1033-1040 ; 02731223 (ISSN) Mohseni, M ; Sharifi Abdar, P. S ; Borghei, S. M ; Sharif University of Technology
    IWA Publishing  2016
    In this study a membrane biological reactor (MBR) was operated at 25±1 °C and pH = 7.5±0.5 to treat synthetic wastewater containing high phenol concentrations. Removal efficiencies of phenol and chemical oxygen demand (COD)were evaluated at four various hydraulic retention times (HRTs) of 24, 12, 8, and 4 hours. The removal rate of phenol (5.51 kg-Phenol kg-VSS-1 d-1), observed at HRT of 4 h,was the highest phenol degradation rate in the literature.According toCODtests, therewere no significant organic matter in the effluent, and phenol was degraded completely by mixed culture. Substrate inhibition was calculated from experimental growth parameters using the Haldane, Yano, and Edward...