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Pourianfar H.R.,Swinburne University of Technology | Pourianfar H.R.,Iranian Academic Center for Education | Poh C.L.,Swinburne University of Technology | Poh C.L.,Sunway University | And 2 more authors.
Virus Research | Year: 2012

Enterovirus 71 (EV71) is the causative agent of hand foot and mouth disease (HFMD) and can also cause fatal neurological complications for which currently there is no vaccine or approved antiviral drug. Despite suggestions that heparan sulfate (HS)-like compounds are effective antivirals against various viruses, no research has been undertaken to examine their effects upon EV71. Therefore, this study aimed to investigate the in vitro anti-EV71 effect of HS mimetics (heparin, heparan sulfate, and pentosan polysulfate). The results revealed that all of the compounds exhibited significant antiviral actions (p< 0.05) against EV71 at concentrations less than 250 μg/mL, compared to virus control and positive control, ribavirin. Among the compounds, heparin exhibited the most potent antiviral activity, as 7.81 μg/mL of it prevented the infection by more than 90% (p< 0.05). Assays to reveal the mode of action revealed that all of the compounds were capable of exerting antiviral activity through hindrance of viral attachment to the cells. In addition, some of the compounds could inhibit viral replication when added to cells 1. h before infection, but none significantly reduced viral penetration. Overall, this research revealed that HS mimetic compounds could inhibit EV71 infection, and that HS may be involved in EV71-host cell interactions, as the virus binding to the host cells was significantly hindered by the HS-like compounds but not by ribavirin. Thus, further investigations to discover the molecular mechanisms underlying the anti-EV71 action of HS-like compounds are warranted. © 2012 Elsevier B.V.

Matin A.A.,University of Tabriz | Biparva P.,Sari University of Agricultural Sciences and Natural Resources | Gheshlaghi M.,Iranian Academic Center for Education
Journal of Chromatography A | Year: 2014

A novel solid-phase microextraction fiber was prepared based on multiwalled carbon nanotubes (MWCNTs) loaded on hollow fiber membrane pores. Stainless steel wire was used as unbreakable support. The major advantages of the proposed fiber are its (a) high reproducibility due to the uniform structure of the hollow fiber membranes, (b) high extraction capacity related to the porous structure of the hollow fiber and outstanding adsorptive characteristics of MWCNTs. The proposed fiber was applied for the microextraction of five representative polycyclic aromatic hydrocarbons (PAHs) from aqueous media (river and hubble-bubble water) and smoked rice samples followed by gas chromatographic determination. Analytical merits of the method, including high correlation coefficients [(0.9963-0.9992) and (0.9982-0.9999)] and low detection limits [(9.0-13.0ngL-1) and (40.0-150.0ngkg-1)] for water and rice samples, respectively, made the proposed method suitable for the ultra-trace determination of PAHs. © 2014 Elsevier B.V.All rights reserved.

Gholizadeh S.,Urmia University | Moghadas R.,Iranian Academic Center for Education
Advances in Structural Engineering | Year: 2014

The main aim of this work is to present a methodology for performance-based optimum seismic design of moment resisting steel frame structures. In the present study, an improved quantum particle swarm optimization (IQPSO) metaheuristic algorithm is proposed to implement performance-based optimum design (PBOD) process. During the optimization process, QPSO and IQPSO algorithms minimize the structural weight subject to performance constraints on inter-story drift ratios based on FEMA-356 provisions at the immediate occupancy (IO), life safety (LS) and collapse prevention (CP) performance levels. Nonlinear pushover analysis is conducted to compute the necessary structural responses during the PBOD process. Two numerical examples are presented to illustrate the efficiency of the presented methodology. The numerical results demonstrate the superiority of the proposed IQPSO to the classical QPSO algorithm.

Eshaghi A.,Iran University of Science and Technology | Graeli A.,Iranian Academic Center for Education
Optik | Year: 2014

In this research, indium tin oxide (ITO) thin films of various thickness (200, 250, 300, 350, 400 nm) were deposited on polycarbonate polymer substrates using a magnetron sputtering technique. The structure, morphology, surface composition, optical and electrical properties of the thin films were investigated by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FE-SEM), X-ray Photoelectron Spectroscopy (XPS), UV-VIS-NIR spectrophotometer and four point probe method, respectively. The results indicated that grain size increased as the thickness increased. The transmittance and sheet resistance of the ITO thin films showed that ITO thin films with 200 nm thickness had the highest transmission whereas ITO thin film with 400 nm had the best conductivity.

Farhadi K.,Urmia University | Maleki R.,Iranian Academic Center for Education
Journal of the Chinese Chemical Society | Year: 2011

A simple and sensitive method based on dispersive liquid-liquid microextraction (DLLME) in conjunction with high performance liquid chromatography-diode array detection (HPLC-DAD) has been developed for the quantitative analysis of patulin in apple juice and concentrate samples. The effect of extraction and disperser solvent (nature and volume), pH of sample solution, extraction time and extraction temperature was investigated. Under the optimal conditions the linear dynamic range of patulin was from 8.0 to 40.0 μg L -1 with a correlation coefficient of 0.9993 and a detection limit of 4.0 μg L -1. The relative standard deviation (RSD) was less than 5.9% (n = 5) and the recovery values were in the range of 94-97%. Finally the proposed method was successfully applied for the analysis of patulin in apple juice and concentrate samples.

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