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    Expression of functional recombinant human tissue transglutaminase (TG2) using the bac-to-bac baculovirus expression system

    , Article Advanced Pharmaceutical Bulletin ; Volume 6, Issue 1 , 2016 , Pages 49-56 ; 22285881 (ISSN) Yazdani, Y ; Azari, S ; Kalhor, H. R ; Sharif University of Technology
    Tabriz University of Medical Sciences 
    Tissue transglutaminase (TG2) is a unique multifunctional enzyme. The enzyme possesses enzymatic activities such as transamidation/crosslinking and non-enzymatic functions such as cell migration and signal transduction. TG2 has been shown to be involved in molecular mechanisms of cancers and several neurodegenerative diseases such as Alzheimer's disease. The present study aimed at cloning and expression of full length human TG2 in Bac-to-Bac baculovirus expression system and evaluation of its activity. Methods: pFastBac HTA donor vector containing coding sequence of human TG2 was constructed. The construct was transformed to DH10Bac for generating recombinant bacmid. The verified bacmid was... 

    Chlorophyll-based wicking sensing bioplatform coupled with a smartphone-based sample-to-answer analytical device for on-site detection of picric acid

    , Article Biosensors and Bioelectronics: X ; Volume 11 , 2022 ; 25901370 (ISSN) Shafizadeh, M ; Abbasi Moayed, S ; Hamzei, Z ; Keshavarz, A ; Yousefi, S ; Hormozi Nezhad, M. R ; Golmohammadi, H ; Sharif University of Technology
    Elsevier Ltd  2022
    The development of inexpensive, equipment-free, portable, and user/environmentally-friendly analytical devices that can be efficiently utilized for on-site detection of PA is still a great challenge. To address these unmet demands, we have developed a smartphone-based disposable sensing bioplatform through immobilization of chlorophyll in a cotton thread for fluorescent monitoring of picric acid (PA). The fluorescence quenching of chlorophyll upon increasing the PA concentration based on the inner filter effect was considered as the sensing strategy in the developed sensor. The fabricated thread-based microfluidic sensing bioplatform was further coupled with a compact, low cost, portable,... 

    Amyloid fibril reduction through covalently modified lysine in HEWL and insulin

    , Article Archives of Biochemistry and Biophysics ; Volume 727 , 2022 ; 00039861 (ISSN) Rezaei, M ; Kalhor, H. R ; Sharif University of Technology
    Academic Press Inc  2022
    Proteins possess a variety of nucleophiles, which can carry out different reactions in the functioning cells. Proteins endogenously and synthetically can be modified through their nucleophilic sites. The roles of these chemical modifications have not been completely revealed. These modifications can alter the protein folding process. Protein folding directly affects the function of proteins. If an error in protein folding occurs, it may cause protein malfunction leading to several neurodegenerative disorders such as Alzheimer's and Parkinson's. In this study, Hen Egg White Lysozyme (HEWL) and bovine insulin, as model proteins for studying the amyloid formation, were covalently attached with... 

    Determination of spermine and spermidine in meat with a ratiometric fluorescence nanoprobe and a combinational logic gate

    , Article Food Chemistry ; Volume 384 , 2022 ; 03088146 (ISSN) Abbasi-Moayed, S ; Bigdeli, A ; Hormozi Nezhad, M. R ; Sharif University of Technology
    Elsevier Ltd  2022
    A ratiometric fluorescent nanoprobe is developed with a wide color variation for visual determination of spermine (SP) and spermidine (SD) in meat samples. The green emission provided from the combination of yellow emissive quantum dots and blue emissive carbon dots turns into pink when SP or SD are present. The results show that the developed sensor has good linearity in the range of 0.5–10 and 0.5–80 µM for SP and SD and suitable detection limits were achieved including 0.2 and 2.1 µM for SP and SD. The probe was highly selective in the presence of amino acids and other biogenic amines. RGB indices were extracted to build a combinational logic gate for visual and simultaneous detection of... 

    Toward visual chiral recognition of amino acids using a wide-range color tonality ratiometric nanoprobe

    , Article Analytica Chimica Acta ; Volume 1231 , 2022 ; 00032670 (ISSN) Jafar Nezhad Ivrigh, Z ; Fahimi Kashani, N ; Morad, R ; Jamshidi, Z ; Hormozi Nezhad, M. R ; Sharif University of Technology
    Elsevier B.V  2022
    Chiral recognition has long been a challenging issue to deal with in biological systems, drug design and food authentication. Implementing nanoparticle-based probes with intrinsic or induced chirality in this field has addressed several issues concerning sensitivity, reliability, rapidness and the cost of chiral sensing platforms. Yet, research into chiral nanoprobes that can be used for visual monitoring of chiral substances is still in its infancy. As part of this study, a visual chiral recognition platform has been developed in which a combination of blue-emitting carbon dots (BCDs) and mercaptopropionic acid-capped CdTe quantum dots (MPA-QDs) with inherent chiroptical activity were... 

    Immersed sol-gel based amino-functionalized SPME fiber and HPLC combined with post-column photochemically induced fluorimetry derivatization and fluorescence detection of pyrethroid insecticides from water samples

    , Article Journal of Separation Science ; Volume 32, Issue 17 , 2009 , Pages 2912-2918 ; 16159306 (ISSN) Bagheri, H ; Ghanbarnejad, H ; Khalilian, F ; Sharif University of Technology
    A method based on direct immersion solid-phase microextraction (DI-SPME) coupled with high performance liquid chromatography combined with post-column photochemically induced fluorimetry derivatization and fluorescence detection (HPLC-PIF-FD) was developed to extract three pyrethroid insecticides, i.e. cyfluthrin, cypermethrin, and flumethrin from water samples. A sol-gel based coating fiber using 3-(trimethoxysilyl propyl) amine as precursor was prepared and used for the extraction of the pyrethroids from groundwater samples. A post-column photochemical reactor was designed and constructed for the derivatization of these environmentally important pollutants to increase their fluorescence...