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Shabani I.,Amirkabir University of Technology | Haddadi-Asl V.,Amirkabir University of Technology | Seyedjafari E.,University of Tehran | Seyedjafari E.,Stem Cell Technology Research Center | Soleimani M.,Tarbiat Modares University
Biochemical and Biophysical Research Communications | Year: 2012

Electrospinning is currently used to fabricate nanofibrous scaffolds for tissue engineering applications. The major problem of these scaffolds is their intrinsically two-dimensional nature which inhibits cellular migration and in-growth. In this study, we have introduced a modified setup of electrospinning to produce three-dimensional nanofibrous scaffolds which allows improved infiltration of cells. An array of focused halogen light bulbs was used to localize the heat in the path of electrospun jet near the collector. The fabricated mats were then seeded with cells in order to evaluate migration and infiltration. After 14. days of culture, a homogenous distribution of cells was observed throughout the scaffolds and showed the three-dimensional architecture of nanofibrous mats. By this novel and simple setup, the prepared electrospun mats will allow the seeded cells to obtain a three-dimensional arrangement which is ideal for tissue engineering applications. © 2012 . Source


Jafary H.,University of Tehran | Ahmadian S.,University of Tehran | Soleimani M.,Tarbiat Modares University | Soleimani M.,Stem Cell Technology Research Center
Tumor Biology | Year: 2014

Acetylation of histone is a major player in epigenetic modifications, resulting in open chromatin structures and, hence, permissive conditions for transcription-factor recruitment to the promoters, followed by initiation of transcription. Histone deacetylase inhibitors arrest cancer cell growth and cause apoptosis with low toxicity thereby constituting a promising treatment for cancer. In this study, we examined the antiproliferative effects of valproate with a combination of nicotinamide in the MCF-7 cell line. MCF-7 was treated with various concentrations of valproate. The MTT assay showed that the viability of MCF-7 cells was inhibited and the cell activity was decreased. Viability percent of valproate and nicotinamide combined treatment cells (28 ± 2) was 1.78 times increased compared with the valproate-alone (0.5 mM) treated cells (50 ± 2). Colony formation in soft agar indicated that valproate at 0.3 mM, when used alone, weakly suppressed proliferation of cells (82 ± 3) and the combination treatment of valproate + nicotinamide strongly suppressed cell proliferation (51 ± 3). The flow cytometric and microscopic analyses of HDACI combined with treated cells indicated strong apoptosis induction and nuclear morphological alterations greater than those of valproate alone. Real-time reverse transcriptase-polymerase chain reaction (RT-PCR) analysis confirmed the efficiency of the HDAC inhibitor combination, revealing the effectively upregulated p16 and p21. Furthermore, to investigate the role of acetyl-histone H3 levels, western blot analyses have been performed and high levels of acetylated histone H3 were detected in valproate- and nicotinamide-treated cells. These results suggest that the combination treatment of valproate with nicotinamide exerts significant antitumor activity and could be a promising therapeutic candidate to treat human breast cancer. © 2013 International Society of Oncology and BioMarkers (ISOBM). Source


Hasani-Sadrabadi M.M.,Amirkabir University of Technology | Hasani-Sadrabadi M.M.,Ecole Polytechnique Federale de Lausanne | Shabani I.,Amirkabir University of Technology | Shabani I.,Stem Cell Technology Research Center | And 2 more authors.
Journal of Power Sources | Year: 2011

New types of triple-layer membranes were fabricated using multi-step impregnation of Nafion in electrospun webs based on bead-free nanofibers of sulfonated poly(ether sulfone) (SPES). The results showed that the fabricated nanofiber-filled membrane owing to its reduced methanol permeability as well as sufficient proton conductivity and membrane selectivity can be used as a promising proton exchange membrane for direct methanol fuel cell (DMFC) applications. The single cell DMFC performance results revealed that the SPES nanofiber-based triple-layer membranes have higher electrochemical performance than commercial Nafion membranes. © 2011 Elsevier B.V. All rights reserved. Source


Ardeshirylajimi A.,Stem Cell Technology Research Center | Dinarvand P.,Stem Cell Technology Research Center | Seyedjafari E.,University of Tehran | Langroudi L.,Stem Cell Technology Research Center | And 2 more authors.
Cell and Tissue Research | Year: 2013

Tissue engineering with a combination of stem cells and nanofibrous scaffolds has attracted interest with regard to bone regeneration applications. In the present study, human induced pluripotent stem cells (iPSCs) were cultured on polymeric nanofibrous polyethersulfone (PES) with and without plasma treatment. The capacity of PES and plasma-treated PES (Plasma-PES) scaffolds to support the proliferation and osteogenic differentiation of iPSCs was investigated by MTT assay and for common osteogenic markers such as alkaline phosphatase activity, calcium mineral deposition and bone-related genes. Plasma-PES scaffolds with or without iPSCs were subsequently used to evaluate bone regeneration of critical-size defects in the rat by digital mammography, multislice spiral-computed tomography imaging and histological analysis. The results of in vitro analysis showed that plasma treatment significantly enhanced iPSC proliferation and osteogenesis. After 8 weeks of iPSC-loaded Plasma-PES implantation, no mortality or complication was observed in animals or at the site of surgery. Imaging analysis revealed more extensive bone reconstruction in rats receiving nanofibers compared with untreated control groups. Moreover, Plasma-PES seeded with iPSCs induced the highest regeneration of bone defects among all groups. These findings were confirmed by histological staining. Affective osseointegration was observed in implanted scaffolds. Thus, plasma-treated nanofibrous scaffolds are suitable tissue-engineered matrices for supporting the proliferation and osteogenic differentiation of iPSCs and might also be appropriate for the reconstruction of bone defects. © 2013 Springer-Verlag Berlin Heidelberg. Source


Seyedjafari E.,University of Tehran | Seyedjafari E.,Stem Cell Technology Research Center | Soleimani M.,Tarbiat Modares University | Ghaemi N.,University of Tehran | And 2 more authors.
Biomacromolecules | Year: 2010

A combination of calcium phosphates with nanofibrous scaffolds holds promising potential for bone tissue engineering applications. In this study, nanohydroxyapatite (n-HA) was coated on the plasma-treated surface of electrospun poly(L-lactide) (PLLA) nanofibers and the capacity of fabricated scaffolds for bone formation was investigated in vitro using human cord blood derived unrestricted somatic stem cells (USSC) under osteogenic induction and in vivo after subcutaneous implantation. PLLA and n-HA-coated PLLA (n-HA/PLLA) scaffolds exhibited a nanofibrous structure with interconnected pores and suitable mechanical properties. These scaffolds were also shown to support attachment, spreading, and proliferation of USSC, as shown by their flattened normal morphology and MTT assay. During osteogenic differentiation, significantly higher values of ALP activity, biomineralization, and bone-related gene expression were observed on n-HA/PLLA compared to PLLA scaffolds. Subsequently, these markers were measured in higher amounts in USSC on PLLA nanofibers compared to TCPS. According to the in vivo results, ossification and formation of trabeculi was observed in the n-HA/PLLA scaffold compared to PLLA. Taking together, it was shown that nanofibrous structure enhanced osteogenic differentiation of USSC. Furthermore, surface-coated n-HA stimulated the effect of nanofibers on the orientation of USSC toward osteolineage. In addition, the n-HA/PLLA electrospun scaffold showed the capacity for ectopic bone formation in the absence of exogenous cells. © 2010 American Chemical Society. Source

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