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    Highly efficient hydroxyapatite/TiO2 composites covered by silver halides as E. coli disinfectant under visible light and dark media

    , Article Photochemical and Photobiological Sciences ; Volume 12, Issue 10 , 2013 , Pages 1787-1794 ; 1474905X (ISSN) Azimzadehirani, M ; Elahifard, M ; Haghighi, S ; Gholami, M ; Sharif University of Technology
    TiO2-based photocatalysts are seen as the most common agents for the photodegradation of bacteria. In this study, AgCl/TiO2, hydroxyapatite(Hp)/AgCl/TiO2, AgI/TiO2, and Hp/AgI/TiO2 were prepared by the deposition-precipitation method on P25 TiO2 nanoparticles and were characterized by XRD, SEM, FT-IR, EDX and BET methods. The prepared composites showed high efficiency for the inactivation of Escherichia coli (E. coli) bacteria under visible light and in dark media with different catalyst amounts of 12 and 24 mg, respectively. In less than 30 min, AgI/TiO2, prepared by the combination of cationic surfactant and PVPI2, disinfected 1 × 107 colony-forming units of E. coli completely. However,... 

    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... 

    In vitro biological outcome of laser application for modification or processing of titanium dental implants

    , Article Lasers in Medical Science ; Volume 32, Issue 5 , 2017 , Pages 1197-1206 ; 02688921 (ISSN) Hindy, A ; Farahmand, F ; Tabatabaei, F. S ; Sharif University of Technology
    There are numerous functions for laser in modern implant dentistry including surface treatment, surface coating, and implant manufacturing. As laser application may potentially improve osseointegration of dental implants, we systematically reviewed the literature for in vitro biological responses to laser-modified or processed titanium dental implants. The literature was searched in PubMed, ISI Web, and Scopus, using keywords “titanium dental implants,” “laser,” “biocompatibility,” and their synonyms. After screening the 136 references obtained, 28 articles met the inclusion criteria. We found that Nd:YAG laser was the most commonly used lasers in the treatment or processing of titanium... 

    Polyphenols attached graphene nanosheets for high efficiency NIR mediated photodestruction of cancer cells

    , Article Materials Science and Engineering C ; Volume 33, Issue 3 , 2013 , Pages 1498-1505 ; 09284931 (ISSN) Abdolahad, M ; Janmaleki, M ; Mohajerzadeh, S ; Akhavan, O ; Abbasi, S ; Sharif University of Technology
    Green tea-reduced graphene oxide (GT-rGO) sheets have been exploited for high efficiency near infrared (NIR) photothermal therapy of HT29 and SW48 colon cancer cells. The biocompatibility of GT-rGO sheets was investigated by means of MTT assays. The polyphenol constituents of GT-rGO act as effective targeting ligands for the attachment of rGO to the surface of cancer cells, as confirmed by the cell granularity test in flow cytometry assays and also by scanning electron microscopy. The photo-thermal destruction of higher metastatic cancer cells (SW48) is found to be more than 20% higher than that of the lower metastatic one (HT29). The photo-destruction efficiency factor of the GT-rGO is... 

    Intravenous laser wavelength radiation effect on LCAT, PON1, catalase, and FRAP in diabetic rats

    , Article Lasers in Medical Science ; Volume 35, Issue 1 , 2020 , Pages 131-138 Amjadi, A ; Mirmiranpour, H ; Sobhani, S. O ; Moazami Goudarzi, N ; Sharif University of Technology
    Springer  2020
    The main purpose of this study is to evaluate the effect of intravenous irradiation of different low-level laser wavelengths on the activity of lecithin-cholesterol acyltransferase (LCAT), paraoxonase (PON1), catalase, and ferric reducing ability of plasma (FRAP) in diabetic rats. First, diabetes was induced in rats using streptozotocin (STZ). Enzymes’ activity was measured in the blood samples and compared before and after intravenous laser blood irradiation. We used four continuous-wave lasers—IR (λ = 808 nm), Red (λ = 638 nm), Green (λ = 532 nm), and Blue (λ = 450 nm)—to compare the wavelength’s effect on different enzymes’ activity. Laser power was fixed at 0.01 mW and laser energy was... 

    The effect of energy spectrum change on DNA damage in and out of field in 10-MV clinical photon beams

    , Article Medical and Biological Engineering and Computing ; Volume 53, Issue 1 , January , 2015 , Pages 67-75 ; 01400118 (ISSN) Ezzati, A. O ; Xiao, Y ; Sohrabpour, M ; Studenski, M. T ; Sharif University of Technology
    Springer Verlag  2015
    The aim of this study was to quantify the DNA damage induced in a clinical megavoltage photon beam at various depths in and out of the field. MCNPX was used to simulate 10 × 10 and 20 × 20 cm2 10-MV photon beams from a clinical linear accelerator. Photon and electron spectra were collected in a water phantom at depths of 2.5, 12.5 and 22.5 cm on the central axis and at off-axis points out to 10 cm. These spectra were used as an input to a validated microdosimetric Monte Carlo code, MCDS, to calculate the RBE of induced DSB in DNA at points in and out of the primary radiation field at three depths. There was an observable difference in the energy spectra for photons and electrons for points... 

    Near infrared laser stimulation of human neural stem cells into neurons on graphene nanomesh semiconductors

    , Article Colloids and Surfaces B: Biointerfaces ; Volume 126 , 2015 , Pages 313-321 ; 09277765 (ISSN) Akhavan, O ; Ghaderi, E ; Shirazian, S. A ; Sharif University of Technology
    Reduced graphene oxide nanomeshes (rGONMs), as p-type semiconductors with band-gap energy of ~1. eV, were developed and applied in near infrared (NIR) laser stimulation of human neural stem cells (hNSCs) into neurons. The biocompatibility of the rGONMs in growth of hNSCs was found similar to that of the graphene oxide (GO) sheets. Proliferation of the hNSCs on the GONMs was assigned to the excess oxygen functional groups formed on edge defects of the GONMs, resulting in superhydrophilicity of the surface. Under NIR laser stimulation, the graphene layers (especially the rGONMs) exhibited significant cell differentiations, including more elongations of the cells and higher differentiation of...