67 research outputs found

    Vaccination with recombinant 4×M2e.HSP70c fusion protein as a universal vaccine candidate enhances both humoral and cell-mediated immune responses and decreases viral shedding against experimental challenge of H9N2 influenza in chickens

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    As cellular immunity is essential for virus clearance, it is commonly accepted that no adequate cellular immunity is achieved by all available inactivated HA-based influenza vaccines. Thus, an improved influenza vaccine to induce both humoral and cell-mediated immune responses is urgently required to control LPAI H9N2 outbreaks in poultry farms. M2e-based vaccines have been suggested and developed as a new generation of universal vaccine candidate against influenza A infection. Our previous study have shown that a prime-boost administration of recombinant 4 × M2e. HSP70c (r4M2e/H70c) fusion protein compared to conventional HA-based influenza vaccines provided full protection against lethal dose of influenza A viruses in mice. In the present study, the immunogenicity and protective efficacy of (r4M2e/H70c) was examined in chickens. The data reported herein show that protection against H9N2 viral challenge was significantly increased in chickens by injection of r4M2e/H70c compared with injection of conventional HA-based influenza vaccine adjuvanted with MF59 or recombinant 4 × M2e (r4M2e) without HSP70c. Oropharyngeal and cloacal shedding of the virus was detected in all of the r4M2e/H70c vaccinated birds at 2 days after challenge, but the titer was low and decreased rapidly to reach undetectable levels at 7 days after challenge. Moreover, comparison of protective efficacy against LPAI H9N2 in birds intramuscularly immunized with r4M2e/H70c likely represented the ability of the M2e-based vaccine in providing cross-protection against heterosubtypic H9N2 challenge and also allowed the host immune system to induce HA-homosubtype neutralizing antibody against H9N2 challenge. This protective immunity might be attributed to enhanced cell-mediated immunity, which is interpreted as increased lymphocytes proliferation, increased levels of Th1-type (IFN-γ) and Th2-type (IL-4) cytokines production and increased CD4+ to CD8+ ratios, resulting from the injection of four tandem repeats of the ectodomain of the conserved influenza matrix protein M2 (4×M2e) genetically fused to C-terminus of Mycobacterium tuberculosis HSP70 (mHSP70c). © 2014 Elsevier B.V

    Making a symbolic gesture: a qualitative examination of self-immolation in Iran

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    Self-immolation is one of the most dramatic methods of committing suicide. Some regions in Iran have a high prevalence of suicide by this method. This study aims to understand and explore the experience of self-immolated women in Iran. Twenty women have interviewed in the burns centers of three different cities immediately the following hospitalization due self-immolation, and the data was analyzed using conventional content analysis. The results were categorized in three main categories: Cultural background and preparing the stage, making a symbolic gesture and events of the day of the incident. Making a symbolic gesture consists of the critical elements of self-immolation, including the presence of significant others, dramatic presentation of misery, bringing an end to misfortune, proof of innocence, creating a sense of compassion or guilt and inspiration from similar cases. The social situation of women in Iran is contributing to self-immolation through feelings of anger and helplessnes

    Fabrication and characterization of cobalt- and copper-doped mesoporous borate bioactive glasses for potential applications in tissue engineering

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    Developing novel compositions of bioactive glasses (BGs) is key for accelerating tissue repair and regeneration. In this work, we developed a series of cobalt (Co)- and copper (Cu)-doped mesoporous bioactive glasses (MBGs) based on borate 13-93B3 composition using nitrate precursors. We took benefit from data science algorithms to predict and assess the physico-chemical and biological properties of the samples. The results showed that the presence of the dopants (Co and Cu) in the MBGs could change the glass transition temperature (Tg) (from 773 to 539 °C), the zeta potential (from -12 to -43 mV), and surface area (from 54 to 194 m2/g). However, the presence of 2.5 mol% of dopants in the composition led to just a slight decrease in their bioactivity. In vitro biocompatibility assays confirmed that all the glass samples were biocompatible. Furthermore, the doped MBGs exhibited potent antibacterial activity against both Gram-positive and Gram-negative bacteria. In addition, these glasses could induce the mobility of human umbilical vein endothelial cells (HUVECs) and enhance new blood vessel formation in ovo. According to the obtained data, it can be stated that this type of doped borate MBGs held great promise in tissue engineering applications

    Design and characterization of keratin/PVA-PLA nanofibers containing hybrids of nanofibrillated chitosan/ZnO nanoparticles

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    In this paper, designing electrospun composite nanofibers containing poly (lactic acid) (PLA) and keratin/poly (vinyl alcohol) (K/PVA) as the major components and natural nanofibrillated chitosan (CHNF)/ZnO nanoparticles (ZnONPs) (CSZ) combination as the nanofiller ingredient, has been investigated. PLA solution from one syringe and K/PVA from another one with incorporation of CHNF (CS), CSZ (2:1), (1:1) and (1:2) were electrospun and produced nanofibers were formed on the rotating collector. Addition of CHNF and ZnONPs amounts in CSZ combination resulted in reduction of the diameter of nanofibers. The highest hydrophilicity was reported for K/PVA/CS-PLA/CS sample with the contact angle of about 43 ± 3°. AFM results for K/PVA-PLA, K/PVA/CS-PLA/CS and K/PVA/CSZ(2:1)-PLA/CSZ(2:1), K/PVA/CSZ(1:2)-PLA/CSZ(1:2) samples indicated that the surface roughness factor for these nanofibers was about 708, 277, 378 and 658 nm, respectively. DSC analysis for K/PVA/CSZ(1:2)-PLA/CSZ(1:2) structure exhibited that the peaks related to the melting points of PLA and PVA shifted to higher temperatures. Overally, K/PVA/CSZ(2:1)-PLA/CSZ(2:1) nanofiber with diameter of 352.50 ± 31 nm, contact angle of 48 ± 3°, tensile strength of 0.96 ± 0.18 MPa is suggested as a proper wound healing scaffold that has highest antibacterial as well as potential to increase cell proliferation. © 202

    Smart electrospun nanofibers containing PCL/gelatin/graphene oxide for application in nerve tissue engineering

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    Currently graphene-doped electrospun scaffolds have been a matter of great interest to be exploited in biomedical fields such as tissue engineering and drug delivery applications. The main objective of this paper is to evaluate the effect of graphene on biological properties of PCL/gelatin nanofibrous mats. SEM analysis was conducted to investigate the morphology of the electrospun nanofibers. The in-vitro cellular proliferation of PC12 cells on nanofibrous web was also investigated. Electrospun PCL/gelatin/graphene nanofibrous mats exhibited 99 antibacterial properties against gram-positive and gram-negative bacteria. Drug release studies indicated that the �-� stacking interaction between TCH and graphene has led to the far better controlled release of TCH from electrospun PCL/gelatin/graphene compared to PCL/gelatin nanofibrous scaffolds. These superior properties along with an improvement in hydrophilicity and biodegradation features has made the nanofibers a promising candidate to be used as electrically conductive scaffolds in neural tissue engineering as well as controlled drug delivery. © 2019 Elsevier B.V

    Multi-cellular tumor spheroids formation of colorectal cancer cells on Gelatin/PLCL and Collagen/PLCL nanofibrous scaffolds

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    In recent years, more attention has been drawn to development of three-dimensional in-vitro tumor models, Multi Cellular Tumor Spheroids (MCTS), due to their similarity to in vivo tumors models. Interaction of tumor cells with the extracellular matrix (ECM) has an important role in stimulating microenvironmental signaling and MCTS formation. Recently, a number of scaffolds based on natural-nano pattering have been proposed which can superbly mimic the topographical and biochemical features of ECM. In this study, we investigated whether the natural-synthetic polymer nanofibers can promote the three-dimensional (3D) MCTS formation of HT29 colorectal cancer cells in compare to synthetic nanofibers. Nanofibers were fabricated by blending of collagen (Col) and gelatin (Gel) with poly (L-lactide co-ε-caprolactone) (PLCL) polymer, separately. Generally, nanofibers exhibited proper structural properties in term of morphology, hydrophilic nature and mechanical integrity. The results revealed that HT29 colorectal cancer cells can form 3D spheroids with uniform morphology and smooth surface on both Col/PLCL and Gel/PLCL nanofibers while the spheroids were unstable and irregular in shape on PLCL nanofibers. In addition, the cells were dispersed on non-coated plates as confluent cell monolayer. There were no significant differences between the number and diameter of MCTSs on both Col/PLCL and Gel/PLCL nanofibers. On the other hand, the radio resistance of cells on Col/PLCL and Gel/PLCL nanofibers was higher compared with either PLCL nanofibers or non-coated plates. In conclusion, the results showed that scaffolds provided by Col/PLCL and Gel/PLCL nanofibers can mimic the properties of ECM in case of in vitro MCTS formation so they can be suggested to use in tumor drug screening studies. © 2019 Elsevier Lt

    Designing hybrid nanofibers based on keratin-poly (vinyl alcohol) and poly (�-caprolactone) for application as wound dressing

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    In this study, the production of hybrid scaffolds containing keratin/polyvinyl alcohol (Ker/PVA) and poly (�-caproactone) (PCL) for application in skin regeneration has been investigated. In the first step, the extraction of keratin from wool fibers was done, and then electrospinning process was used to fabricate hybrid nanofibers. Ker/PVA blend solution was extruded from one syringe and poly(ε-caprolactone) solution from the other one and hybrid nanofibers were gathered onto a rotary drum collector. The effect of different ratios of Ker/PVA (30:70), (50:50), and (70:30) with PCL were studied on the morphology, hydrophilicity and mechanical features of the scaffolds. The Ker/PVA (50:50)-PCL nanofibers presented an appropriate modulus and mechanical strength similar to the natural skin. These scaffolds possessed high levels of hydrophilicity, which improved cell-scaffold adhesion and increased the growth and proliferation of fibroblast cells. Keratin based nanofibers demonstrated antibacterial characteristic against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. © The Author(s) 2021
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