Mahmoud Azami | Tehran University of Medical Sciences (original) (raw)
Papers by Mahmoud Azami
In this study, 45S5 bioglass and copper-doped 45S5 bioglass nanoparticles were prepared using sol... more In this study, 45S5 bioglass and copper-doped 45S5 bioglass nanoparticles were prepared using sol gel technique, copper doped in the structure of 45S5 bioglass at three concentration to determine a biocompatible and effective concentration that is appropriate for Tissue engineering application. The prepared nanoparticles were analyzed using Fourier Transform Infrared Spectroscopy (FTIR), as we ray diffraction (XRD) analysis and EDAX. The nanostructures of the prepared samples were analyzed using Scanning Electron Microscopy (SEM). The effects of the doped copper were studied on the cytotoxicity of the 45S5 bioglass nanoparticles structu indirectly using MTT analysis by L929 mouse fibroblast cells. It was shown that increasing the concentration of copper can decrease the glass transition temperatures, and affecting the structure of 45S5 bioglass, although increasing the copper content were cyto assay revealed 1% copper is suitable for cell viability and is no toxic.
Journal of Advanced Research
Biomedicine & Pharmacotherapy
Journal of Ophthalmic & Vision Research, 2021
Purpose Considering the significance of retinal disorders and the growing need to employ tissue e... more Purpose Considering the significance of retinal disorders and the growing need to employ tissue engineering in this field, in-silico studies can be used to establish a cost-effective method. This in-silico study was performed to find the most effective growth factors contributing to retinal tissue engineering. Methods In this study, a regeneration gene database was used. All 21 protein-coding genes participating in retinal regeneration were considered as a protein–protein interaction (PPI) network via the “STRING App” in “Cytoscape 3.7.2” software. The resultant graph possessed 21 nodes as well as 37 edges. Gene ontology (GO) analysis, as well as the centrality analysis, revealed the most effective proteins in retinal regeneration. Results According to the biological processes and the role of each protein in different pathways, selecting the correct one is possible through the information that the network provides. Eye development, detection of the visible light, visual perception, ...
During past decade, using biomimetic approaches has received much attention by scientists in the ... more During past decade, using biomimetic approaches has received much attention by scientists in the field of tissue substitutes preparation. These approaches have been employed for synthesis of bone tissue engineering scaffolds in the case of either materials or synthesis methods. In this study, an apatite phase has been synthesized within gelatin hydrogel in biomimetic condition. The obtained composite hydrogel has changed to a porous scaffold with the application of freeze drying technique in order to be used in bone tissue engineering. To characterize the chemical composition and crystal structure of the synthesized precipitate within hydrogel, FTIR, XRD and TEM analysis were used. Surface morphology and porous structure of the scaffold were studied with SEM. SEM analysis was also used to investigate the quality of cultured osteoblast cells activity. Results approved formation of an apatite phase within gelatin hydrogel in biomimetic condition with crystallite size ranging between 7...
EXCLI Journal, 2018
Due to the restricted potential of the heart to regenerate its damaged region, stem cell therapy ... more Due to the restricted potential of the heart to regenerate its damaged region, stem cell therapy is a promising treatment modality for myocardial infarction. It has been shown that incubation of bone marrow-derived stromal cells (BMSCs) with initial steps of cardiac differentiation in vitro, can have a significant effect on their therapeutic potential to treat myocardial infarction. Based on these well-established principals we were encouraged to study the direct co-culture of rat BMSCs with neonatal mouse almost pure cardiomyocytes (APCs) and cardiac niche cells (CNCs) in static 2D and microfluidic cell culture systems. Our results showed that the difference regarding the beating rate in isolated APCs and CNCs in both 2D and the microfluidic system was not statistically significant for 30 days. No beat rate could be observed in induced BMSCs in all groups during experiment time. Except for BMSCs cultured alone in both experimental culture conditions, data obtained from Real-time PC...
Introduction: High surface/volume ratio and 3-dimensionality of nanofibers increases cell-scaffol... more Introduction: High surface/volume ratio and 3-dimensionality of nanofibers increases cell-scaffold interactions and promote migration and proliferation of cells. Wet electrospinning is a variant of electrospinning technology that is utilized to produce nanofibrous scaffolds. Altering the parameters governing the wet electrospinning process such as applied voltage, polymer concentration, composition and depth of the coagulation bath, and tip to bath distance can affect the morphology of the produced scaffolds. In this study, the influence of various coagulation baths on the physicochemical properties of the wet-electrospun nanofibers was investigated. Materials and Methods : Poly (e-caprolactone)/Poly (L-lactic) acid 15% (w/v) blends under an applied voltage of 15 kV, and a tip-to-bath distance of 10 cm. were used to prepare fibrous scaffolds via wet-electrospinning technique into aqueous solution of sodium hydroxide (NaOH) (pH~13), distilled water, ethanol, water/ethanol (3:7) (v/v)...
Introduction: Spinal cord injuries are one of the main causes of disability with devastating neur... more Introduction: Spinal cord injuries are one of the main causes of disability with devastating neurological consequences and secondary conflicts in other organs. Tissue engineering and regenerative medicine have been recognized as novel, promising methods in the treatment of tissue injuries, especially in neurological damage in recent decades. Hydrogels have the advantage of compatibility with damaged tissue, and injectable hydrogels can be applied in minimally invasive surgeries. This study aimed to evaluate an injectable hydrogel-based scaffold consisting of thiolated chitosan and alginate for neural tissue regeneration. Materials and Methods: In the present study, an injectable hydrogel-based containing thiolated chitosan and alginate was prepared. Microbiology and pH tests were performed. Microstructural properties and porosity of scaffold were evaluated by scanning electron microscope (SEM). The swelling /shrinkage ratio and rates of biodegradation were also conducted. Finally, t...
This work is a study on current conditions and what is known as preferred conditions for children... more This work is a study on current conditions and what is known as preferred conditions for children is home and school. Purpose of the research is to conduct this study over Kurdish children (boys and girls between 12 to 14 years old) and their instructors. Statistic group is comprised of all boys and girls attending junior high school in Mahaad, Sanandaj and Kermanshah and sample group includes 350 participants (175 girls and 175 boys) and 50 Male and female instructors, adopted randomly among different school from different social and economic classes. Testing techniques for assessing main hypotheses of the study are ( ) test and in some parts "t" test to investigate presence of meaningless different between boys and girls. Finally results were analyzed using SPSS software. The instructors showed more attention to observance of children's rights in preferred and ideal condition than the students; moreover, we found from the instructors' viewpoint that currently chi...
Journal of Biomedical Materials Research Part A
The main aim of this study was to evaluate the efficacy of cerium oxide nanoparticles (CNPs) enca... more The main aim of this study was to evaluate the efficacy of cerium oxide nanoparticles (CNPs) encapsulated in fabricated hybrid silk-fibroin (SF)/polycaprolactone (PCL) nanofibers as an artificial neural guidance conduit (NGC) applicable for peripheral nerve regeneration. The NGC was prepared by PCL and SF filled with CNPs. The mechanical properties, contact angle, and cell biocompatibility experiments showed that the optimized concentration of CNPs inside SF and SF/PCL wall of conduits was 1% (wt/wt). The SEM image analysis showed the nanoscale texture of the scaffold in different topologies depend on composition with fiber diameters at about 351 ± 54 nm and 420 ± 73 nm respectively for CNPs + SF and CNPs + SF/PCL fibrous mats. Furthermore, contact angle measurement confirmed the hydrophilic behavior of the membranes, ascribable to the SF content and surface modification through modified methanol treatment. The balance of morphological and biochemical properties of hybrid CNPs 1% (wt/wt) + SF/PCL construct improves cell adhesion and proliferation in comparison with lower concentrations of CNPs in nanofibrous scaffolds. The release of CNPs 1% (wt/wt) from both CNPs + SF and CNPs+ SF/PCL fibrous mats was highly controlled and very slow during the extended time of incubation until 60 days. Fabricated double-layered NGC using CNPs + SF and CNPs + SF/PCL fibers was consistent for application in nervous tissue engineering and regenerative medicine from a structural and biocompatible perspective.
Journal of Biomedical Materials Research Part B: Applied Biomaterials
The aim of this study was to prepare a porous scaffold out of 58S bioactive glass as the bare and... more The aim of this study was to prepare a porous scaffold out of 58S bioactive glass as the bare and coated with Zein to improve mechanical properties and acting as a carrier for Kaempferol controlled delivery. Porosity and morphology, mechanical properties, drug release behavior, bioactivity, cell attachment, and biodegradation of the scaffolds were evaluated accordingly. Obtained results indicated that the scaffolds coated by (7wt/v %) Zein solution, showed the highest mechanical strength (3.06 ± 0.4 MPa) and desirable porous morphology. These scaffolds could support bioactivity, cell attachment, and provide sustained drug release in the safe range of Kaempferol concentration confirmed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis. Overall, this study showed that the Zein-coated scaffold possesses superior properties rather than bare scaffold, and the scaffolds coated with 7wt/v % Zein solution could be considered as appropriate scaffolds for bone regeneration.
ACS Biomaterials Science & Engineering
The human amniotic membrane (HAM) has been viewed as a potential regenerative material for a wide... more The human amniotic membrane (HAM) has been viewed as a potential regenerative material for a wide variety of injured tissues because of its collagen-rich content. High degradability of HAM limits its wide practical application in bone tissue engineering. In this study, the natural matrix of the decellularized amniotic membrane was developed by the double diffusion method. The results confirmed a reduction of the amniotic membrane's degradability because of the deposition of calcium and phosphate ions during the double diffusion process. Real-time PCR results showed a high expression of osteogenesis-related genes from adipose-derived mesenchymal stem cells (ADMSCs) cultured on the surface of the developed mineralized amniotic membrane (MAM). Further in vivo experiments were conducted using an MAM preseeded with ADMSCs and a critical-size rat calvarial defect model. Histopathological results confirmed that the MAM + cell sample has excellent potential in bone regeneration.
Journal of Bioactive and Compatible Polymers
In tissue engineering, natural hydrogel scaffolds gained considerable attention due to their bioc... more In tissue engineering, natural hydrogel scaffolds gained considerable attention due to their biocompatibility and similarity to macromolecular-based components in the body. However, their low mechanical strength and high degradation degree limit their biomedical application. By varying the composition of hydrogels, their biochemical and mechanical properties can be improved. In this study, the stability of fibrin and collagen hydrogels and their composites with decellularized Wharton’s jelly extract (DEWJ) was improved using proanthocyanidin (PA) as a cross-linker, extracted from grape seeds. The cytocompatibility, physicochemical and mechanical properties of the hydrogels were evaluated. Human endometrial stem cells (hEnSCs) were seeded on the hydrogels and their attachment, morphology, and proliferation were investigated using a scanning electron and optical microscopy. Our results showed that hydrogels containing DEWJ along with PA enhance cell proliferation and showed higher mec...
International Journal of Polymeric Materials and Polymeric Biomaterials
Abstract In this study, we introduced a novel and modified method to synthesize photocrosslinkabl... more Abstract In this study, we introduced a novel and modified method to synthesize photocrosslinkable chitosan hydrogel. Three methacrylated samples under two concentrations of methacrylic anhydride and using EDC/NHS as a crosslinker were prepared. Methacrylated chitosan obtained under controlled conditions and using EDC/NHS had significant coupling efficiency and capacity of gel formation compared to other samples. Diluted culture media provided a favorable solubility condition for methacrylated chitosan and could be tolerated by cells during gelation time. The hydrogels included interconnected pores ranging 100–300 µm and swelling ratios of 40–400%. The results opened the new aspects for developing novel biomaterials in cell-based therapies. Graphical Abstract
Archives of Neuroscience
The hydrogel efficacy of taurine-loaded chitosan nanoparticle/alginate hydrogel was investigated ... more The hydrogel efficacy of taurine-loaded chitosan nanoparticle/alginate hydrogel was investigated for controlled release of the taurine substrate, which is known as an antioxidative drug. The composition of the fabricated hydrogels was explored by Fouriertransform infrared spectroscopy. The swelling ability and degradation rate of hydrogels were also analyzed in phosphate-buffered saline at the physiological condition and alginate lyase for a period of 21 days. Moreover, morphologies and structure of hydrogels and cells were determined using a scanning electron microscope. The possible cytotoxicity of the fabricated hydrogel was carried out by seeding endometrial stem cells on hydrogels. The results demonstrated that hydrogel of chitosan nanoparticle/alginate hydrogel successfully controlled the release of taurine. We observed that the chitosan nanoparticle/alginate hydrogel possessed adjust swelling ability and degradation rate as compared to neat alginate hydrogel. The results proved that the chitosan nanoparticle/alginate hydrogel is non-cytotoxic and could be utilized as a promising composition in tissue engineering and drug delivery systems.
Journal of Bioactive and Compatible Polymers
This study aimed to develop a recombinant human erythropoietin/aloe vera gel–releasing polyvinyl ... more This study aimed to develop a recombinant human erythropoietin/aloe vera gel–releasing polyvinyl alcohol/chitosan wound dressing by wet-electrospinning method and investigate the synergistic effects of erythropoietin and aloe vera gel on the excisional wound healing. The polyvinyl alcohol/chitosan (4:1 (w/w)) solution was electrospun into an aloe vera gel–containing water coagulation bath and then coated with the recombinant human erythropoietin–loaded chitosan nanoparticles prepared via ionic gelation technique. The developed sponge-like film was able to release the erythropoietin and aloe vera gel for at least 7 and 1 days, respectively. The dressing was non-toxic to L929 fibroblastic cell line and non-adherent to the wound bed with the contact angle of 67.93° ± 2.31°. It also possessed the water-uptake capacity and water vapor transmission rate of 26.40% ± 3.37% and 2584.00 ± 144.67 g m−2, respectively. The in vivo study demonstrated the synergistic wound-healing effects of aloe vera gel and erythropoietin on the full-thickness excisional wounds of Wistar rats. The erythropoietin/aloe vera gel–releasing dressing had significantly (n = 4, p < 0.005) higher wound closure (92.96% ± 10.09%) than the sterile gauze (73.89% ± 2.61%), as the control group, after 2 weeks. The differences observed between the wound closure percentages of the aloe vera gel–releasing dressing (85.93% ± 6.46%) and the erythropoietin/aloe vera gel–releasing dressing and control group were not statistically significant.
Progress in Biomaterials
A hybrid hydrogel was obtained from decellularized extract from Wharton's jelly (DEWJ) and silk f... more A hybrid hydrogel was obtained from decellularized extract from Wharton's jelly (DEWJ) and silk fibroin (SF) and characterized for cartilage tissue engineering. Wharton's jelly was used due to its similarity with articular cartilage in extracellular matrix composition. Also, silk fibroin has good mechanical properties which make this construct appropriate for cartilage repair. Decellularization of Wharton's jelly was verified by DAPI staining, DNA quantification, and PCR analysis. Then, the biochemical composition of DEWJ was determined by ELISA kits for total proteins, collagens, sulfated glycosaminoglycans (sGAG), and transforming growth factor β1 (TGF-β1). After fabricating pure SF and SF/DEWJ hybrid hydrogels, their physical and mechanical properties were characterized by FESEM, Fourier-transform infrared spectroscopy (FTIR) and rheological assays (amplitude and frequency sweeps). Furthermore, cell viability and proliferation were assessed by MTT assay. The results have shown that DEWJ in hybrid hydrogels enhances mechanical properties of the construct relative to pure SF hydrogels. Also, this extract at its 40% concentration in culture media and 20% or 40% concentrations in SF/DEWJ hybrid hydrogels significantly increases population of the cells compared to control and pure SF hydrogel after 7 days. In conclusion, this study proposes the potential of SF/DEWJ hybrid hydrogels for cartilage tissue engineering applications.
Advanced Composites Letters
In this study diffusional method was used to prepare a biomimetic calcium phosphate/gelatin nanoc... more In this study diffusional method was used to prepare a biomimetic calcium phosphate/gelatin nanocomposite as a scaffold for bone and tooth tissue engineering. Incorporation of fluorine into mineral phase of the scaffold was also investigated. Addition of fluoride to the synthesis process caused formation of fluoroapatite and calcium fluoride along with hydroxyapatite within gelatin while in the sample lacking fluorine atoms, hydroxyapatite and octacalcium phosphate were detected. With addition of fluorine within the structure of precipitated minerals, morphology of minerals was dramatically changed from oriented rod-like minerals with rectangular cross section toward spherical particles consisting of smaller crystals with uneven surface scattered over the gelatinous bulk material.
Journal of biomedical materials research. Part B, Applied biomaterials, Jan 20, 2017
Decellularized extracellular matrices (ECM) based materials are routinely used for a variety of c... more Decellularized extracellular matrices (ECM) based materials are routinely used for a variety of clinical applications. Hereof, in vivo application of decellularized ovine small intestinal submucosal (DOSIS) layer as, a scaffold is yet to be investigated. In this study, the effectiveness of the DOSIS scaffold, with or without rat bone marrow mesenchymal stem cells (BM-MSCs), in full-thickness wound healing of critical-sized defect was experimentally studied in a rat model. The experimental groups included; group I (control), group II (DOSIS), and group III (BM-MSCs-seeded DOSIS). Wound healing of all groups was examined and compared clinically and histopathologically on days 7, 14, and 21 postoperation. Our results represented BM-MSCs-seeded DOSIS accelerated wound contraction and healing compared to both the DOSIS alone and control groups. Epithelization was close to completion 21 days postoperation in DOSIS alone. In OSIS with BM-MSCs group, epithelization was faster and had fully ...
In this study, 45S5 bioglass and copper-doped 45S5 bioglass nanoparticles were prepared using sol... more In this study, 45S5 bioglass and copper-doped 45S5 bioglass nanoparticles were prepared using sol gel technique, copper doped in the structure of 45S5 bioglass at three concentration to determine a biocompatible and effective concentration that is appropriate for Tissue engineering application. The prepared nanoparticles were analyzed using Fourier Transform Infrared Spectroscopy (FTIR), as we ray diffraction (XRD) analysis and EDAX. The nanostructures of the prepared samples were analyzed using Scanning Electron Microscopy (SEM). The effects of the doped copper were studied on the cytotoxicity of the 45S5 bioglass nanoparticles structu indirectly using MTT analysis by L929 mouse fibroblast cells. It was shown that increasing the concentration of copper can decrease the glass transition temperatures, and affecting the structure of 45S5 bioglass, although increasing the copper content were cyto assay revealed 1% copper is suitable for cell viability and is no toxic.
Journal of Advanced Research
Biomedicine & Pharmacotherapy
Journal of Ophthalmic & Vision Research, 2021
Purpose Considering the significance of retinal disorders and the growing need to employ tissue e... more Purpose Considering the significance of retinal disorders and the growing need to employ tissue engineering in this field, in-silico studies can be used to establish a cost-effective method. This in-silico study was performed to find the most effective growth factors contributing to retinal tissue engineering. Methods In this study, a regeneration gene database was used. All 21 protein-coding genes participating in retinal regeneration were considered as a protein–protein interaction (PPI) network via the “STRING App” in “Cytoscape 3.7.2” software. The resultant graph possessed 21 nodes as well as 37 edges. Gene ontology (GO) analysis, as well as the centrality analysis, revealed the most effective proteins in retinal regeneration. Results According to the biological processes and the role of each protein in different pathways, selecting the correct one is possible through the information that the network provides. Eye development, detection of the visible light, visual perception, ...
During past decade, using biomimetic approaches has received much attention by scientists in the ... more During past decade, using biomimetic approaches has received much attention by scientists in the field of tissue substitutes preparation. These approaches have been employed for synthesis of bone tissue engineering scaffolds in the case of either materials or synthesis methods. In this study, an apatite phase has been synthesized within gelatin hydrogel in biomimetic condition. The obtained composite hydrogel has changed to a porous scaffold with the application of freeze drying technique in order to be used in bone tissue engineering. To characterize the chemical composition and crystal structure of the synthesized precipitate within hydrogel, FTIR, XRD and TEM analysis were used. Surface morphology and porous structure of the scaffold were studied with SEM. SEM analysis was also used to investigate the quality of cultured osteoblast cells activity. Results approved formation of an apatite phase within gelatin hydrogel in biomimetic condition with crystallite size ranging between 7...
EXCLI Journal, 2018
Due to the restricted potential of the heart to regenerate its damaged region, stem cell therapy ... more Due to the restricted potential of the heart to regenerate its damaged region, stem cell therapy is a promising treatment modality for myocardial infarction. It has been shown that incubation of bone marrow-derived stromal cells (BMSCs) with initial steps of cardiac differentiation in vitro, can have a significant effect on their therapeutic potential to treat myocardial infarction. Based on these well-established principals we were encouraged to study the direct co-culture of rat BMSCs with neonatal mouse almost pure cardiomyocytes (APCs) and cardiac niche cells (CNCs) in static 2D and microfluidic cell culture systems. Our results showed that the difference regarding the beating rate in isolated APCs and CNCs in both 2D and the microfluidic system was not statistically significant for 30 days. No beat rate could be observed in induced BMSCs in all groups during experiment time. Except for BMSCs cultured alone in both experimental culture conditions, data obtained from Real-time PC...
Introduction: High surface/volume ratio and 3-dimensionality of nanofibers increases cell-scaffol... more Introduction: High surface/volume ratio and 3-dimensionality of nanofibers increases cell-scaffold interactions and promote migration and proliferation of cells. Wet electrospinning is a variant of electrospinning technology that is utilized to produce nanofibrous scaffolds. Altering the parameters governing the wet electrospinning process such as applied voltage, polymer concentration, composition and depth of the coagulation bath, and tip to bath distance can affect the morphology of the produced scaffolds. In this study, the influence of various coagulation baths on the physicochemical properties of the wet-electrospun nanofibers was investigated. Materials and Methods : Poly (e-caprolactone)/Poly (L-lactic) acid 15% (w/v) blends under an applied voltage of 15 kV, and a tip-to-bath distance of 10 cm. were used to prepare fibrous scaffolds via wet-electrospinning technique into aqueous solution of sodium hydroxide (NaOH) (pH~13), distilled water, ethanol, water/ethanol (3:7) (v/v)...
Introduction: Spinal cord injuries are one of the main causes of disability with devastating neur... more Introduction: Spinal cord injuries are one of the main causes of disability with devastating neurological consequences and secondary conflicts in other organs. Tissue engineering and regenerative medicine have been recognized as novel, promising methods in the treatment of tissue injuries, especially in neurological damage in recent decades. Hydrogels have the advantage of compatibility with damaged tissue, and injectable hydrogels can be applied in minimally invasive surgeries. This study aimed to evaluate an injectable hydrogel-based scaffold consisting of thiolated chitosan and alginate for neural tissue regeneration. Materials and Methods: In the present study, an injectable hydrogel-based containing thiolated chitosan and alginate was prepared. Microbiology and pH tests were performed. Microstructural properties and porosity of scaffold were evaluated by scanning electron microscope (SEM). The swelling /shrinkage ratio and rates of biodegradation were also conducted. Finally, t...
This work is a study on current conditions and what is known as preferred conditions for children... more This work is a study on current conditions and what is known as preferred conditions for children is home and school. Purpose of the research is to conduct this study over Kurdish children (boys and girls between 12 to 14 years old) and their instructors. Statistic group is comprised of all boys and girls attending junior high school in Mahaad, Sanandaj and Kermanshah and sample group includes 350 participants (175 girls and 175 boys) and 50 Male and female instructors, adopted randomly among different school from different social and economic classes. Testing techniques for assessing main hypotheses of the study are ( ) test and in some parts "t" test to investigate presence of meaningless different between boys and girls. Finally results were analyzed using SPSS software. The instructors showed more attention to observance of children's rights in preferred and ideal condition than the students; moreover, we found from the instructors' viewpoint that currently chi...
Journal of Biomedical Materials Research Part A
The main aim of this study was to evaluate the efficacy of cerium oxide nanoparticles (CNPs) enca... more The main aim of this study was to evaluate the efficacy of cerium oxide nanoparticles (CNPs) encapsulated in fabricated hybrid silk-fibroin (SF)/polycaprolactone (PCL) nanofibers as an artificial neural guidance conduit (NGC) applicable for peripheral nerve regeneration. The NGC was prepared by PCL and SF filled with CNPs. The mechanical properties, contact angle, and cell biocompatibility experiments showed that the optimized concentration of CNPs inside SF and SF/PCL wall of conduits was 1% (wt/wt). The SEM image analysis showed the nanoscale texture of the scaffold in different topologies depend on composition with fiber diameters at about 351 ± 54 nm and 420 ± 73 nm respectively for CNPs + SF and CNPs + SF/PCL fibrous mats. Furthermore, contact angle measurement confirmed the hydrophilic behavior of the membranes, ascribable to the SF content and surface modification through modified methanol treatment. The balance of morphological and biochemical properties of hybrid CNPs 1% (wt/wt) + SF/PCL construct improves cell adhesion and proliferation in comparison with lower concentrations of CNPs in nanofibrous scaffolds. The release of CNPs 1% (wt/wt) from both CNPs + SF and CNPs+ SF/PCL fibrous mats was highly controlled and very slow during the extended time of incubation until 60 days. Fabricated double-layered NGC using CNPs + SF and CNPs + SF/PCL fibers was consistent for application in nervous tissue engineering and regenerative medicine from a structural and biocompatible perspective.
Journal of Biomedical Materials Research Part B: Applied Biomaterials
The aim of this study was to prepare a porous scaffold out of 58S bioactive glass as the bare and... more The aim of this study was to prepare a porous scaffold out of 58S bioactive glass as the bare and coated with Zein to improve mechanical properties and acting as a carrier for Kaempferol controlled delivery. Porosity and morphology, mechanical properties, drug release behavior, bioactivity, cell attachment, and biodegradation of the scaffolds were evaluated accordingly. Obtained results indicated that the scaffolds coated by (7wt/v %) Zein solution, showed the highest mechanical strength (3.06 ± 0.4 MPa) and desirable porous morphology. These scaffolds could support bioactivity, cell attachment, and provide sustained drug release in the safe range of Kaempferol concentration confirmed via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis. Overall, this study showed that the Zein-coated scaffold possesses superior properties rather than bare scaffold, and the scaffolds coated with 7wt/v % Zein solution could be considered as appropriate scaffolds for bone regeneration.
ACS Biomaterials Science & Engineering
The human amniotic membrane (HAM) has been viewed as a potential regenerative material for a wide... more The human amniotic membrane (HAM) has been viewed as a potential regenerative material for a wide variety of injured tissues because of its collagen-rich content. High degradability of HAM limits its wide practical application in bone tissue engineering. In this study, the natural matrix of the decellularized amniotic membrane was developed by the double diffusion method. The results confirmed a reduction of the amniotic membrane's degradability because of the deposition of calcium and phosphate ions during the double diffusion process. Real-time PCR results showed a high expression of osteogenesis-related genes from adipose-derived mesenchymal stem cells (ADMSCs) cultured on the surface of the developed mineralized amniotic membrane (MAM). Further in vivo experiments were conducted using an MAM preseeded with ADMSCs and a critical-size rat calvarial defect model. Histopathological results confirmed that the MAM + cell sample has excellent potential in bone regeneration.
Journal of Bioactive and Compatible Polymers
In tissue engineering, natural hydrogel scaffolds gained considerable attention due to their bioc... more In tissue engineering, natural hydrogel scaffolds gained considerable attention due to their biocompatibility and similarity to macromolecular-based components in the body. However, their low mechanical strength and high degradation degree limit their biomedical application. By varying the composition of hydrogels, their biochemical and mechanical properties can be improved. In this study, the stability of fibrin and collagen hydrogels and their composites with decellularized Wharton’s jelly extract (DEWJ) was improved using proanthocyanidin (PA) as a cross-linker, extracted from grape seeds. The cytocompatibility, physicochemical and mechanical properties of the hydrogels were evaluated. Human endometrial stem cells (hEnSCs) were seeded on the hydrogels and their attachment, morphology, and proliferation were investigated using a scanning electron and optical microscopy. Our results showed that hydrogels containing DEWJ along with PA enhance cell proliferation and showed higher mec...
International Journal of Polymeric Materials and Polymeric Biomaterials
Abstract In this study, we introduced a novel and modified method to synthesize photocrosslinkabl... more Abstract In this study, we introduced a novel and modified method to synthesize photocrosslinkable chitosan hydrogel. Three methacrylated samples under two concentrations of methacrylic anhydride and using EDC/NHS as a crosslinker were prepared. Methacrylated chitosan obtained under controlled conditions and using EDC/NHS had significant coupling efficiency and capacity of gel formation compared to other samples. Diluted culture media provided a favorable solubility condition for methacrylated chitosan and could be tolerated by cells during gelation time. The hydrogels included interconnected pores ranging 100–300 µm and swelling ratios of 40–400%. The results opened the new aspects for developing novel biomaterials in cell-based therapies. Graphical Abstract
Archives of Neuroscience
The hydrogel efficacy of taurine-loaded chitosan nanoparticle/alginate hydrogel was investigated ... more The hydrogel efficacy of taurine-loaded chitosan nanoparticle/alginate hydrogel was investigated for controlled release of the taurine substrate, which is known as an antioxidative drug. The composition of the fabricated hydrogels was explored by Fouriertransform infrared spectroscopy. The swelling ability and degradation rate of hydrogels were also analyzed in phosphate-buffered saline at the physiological condition and alginate lyase for a period of 21 days. Moreover, morphologies and structure of hydrogels and cells were determined using a scanning electron microscope. The possible cytotoxicity of the fabricated hydrogel was carried out by seeding endometrial stem cells on hydrogels. The results demonstrated that hydrogel of chitosan nanoparticle/alginate hydrogel successfully controlled the release of taurine. We observed that the chitosan nanoparticle/alginate hydrogel possessed adjust swelling ability and degradation rate as compared to neat alginate hydrogel. The results proved that the chitosan nanoparticle/alginate hydrogel is non-cytotoxic and could be utilized as a promising composition in tissue engineering and drug delivery systems.
Journal of Bioactive and Compatible Polymers
This study aimed to develop a recombinant human erythropoietin/aloe vera gel–releasing polyvinyl ... more This study aimed to develop a recombinant human erythropoietin/aloe vera gel–releasing polyvinyl alcohol/chitosan wound dressing by wet-electrospinning method and investigate the synergistic effects of erythropoietin and aloe vera gel on the excisional wound healing. The polyvinyl alcohol/chitosan (4:1 (w/w)) solution was electrospun into an aloe vera gel–containing water coagulation bath and then coated with the recombinant human erythropoietin–loaded chitosan nanoparticles prepared via ionic gelation technique. The developed sponge-like film was able to release the erythropoietin and aloe vera gel for at least 7 and 1 days, respectively. The dressing was non-toxic to L929 fibroblastic cell line and non-adherent to the wound bed with the contact angle of 67.93° ± 2.31°. It also possessed the water-uptake capacity and water vapor transmission rate of 26.40% ± 3.37% and 2584.00 ± 144.67 g m−2, respectively. The in vivo study demonstrated the synergistic wound-healing effects of aloe vera gel and erythropoietin on the full-thickness excisional wounds of Wistar rats. The erythropoietin/aloe vera gel–releasing dressing had significantly (n = 4, p < 0.005) higher wound closure (92.96% ± 10.09%) than the sterile gauze (73.89% ± 2.61%), as the control group, after 2 weeks. The differences observed between the wound closure percentages of the aloe vera gel–releasing dressing (85.93% ± 6.46%) and the erythropoietin/aloe vera gel–releasing dressing and control group were not statistically significant.
Progress in Biomaterials
A hybrid hydrogel was obtained from decellularized extract from Wharton's jelly (DEWJ) and silk f... more A hybrid hydrogel was obtained from decellularized extract from Wharton's jelly (DEWJ) and silk fibroin (SF) and characterized for cartilage tissue engineering. Wharton's jelly was used due to its similarity with articular cartilage in extracellular matrix composition. Also, silk fibroin has good mechanical properties which make this construct appropriate for cartilage repair. Decellularization of Wharton's jelly was verified by DAPI staining, DNA quantification, and PCR analysis. Then, the biochemical composition of DEWJ was determined by ELISA kits for total proteins, collagens, sulfated glycosaminoglycans (sGAG), and transforming growth factor β1 (TGF-β1). After fabricating pure SF and SF/DEWJ hybrid hydrogels, their physical and mechanical properties were characterized by FESEM, Fourier-transform infrared spectroscopy (FTIR) and rheological assays (amplitude and frequency sweeps). Furthermore, cell viability and proliferation were assessed by MTT assay. The results have shown that DEWJ in hybrid hydrogels enhances mechanical properties of the construct relative to pure SF hydrogels. Also, this extract at its 40% concentration in culture media and 20% or 40% concentrations in SF/DEWJ hybrid hydrogels significantly increases population of the cells compared to control and pure SF hydrogel after 7 days. In conclusion, this study proposes the potential of SF/DEWJ hybrid hydrogels for cartilage tissue engineering applications.
Advanced Composites Letters
In this study diffusional method was used to prepare a biomimetic calcium phosphate/gelatin nanoc... more In this study diffusional method was used to prepare a biomimetic calcium phosphate/gelatin nanocomposite as a scaffold for bone and tooth tissue engineering. Incorporation of fluorine into mineral phase of the scaffold was also investigated. Addition of fluoride to the synthesis process caused formation of fluoroapatite and calcium fluoride along with hydroxyapatite within gelatin while in the sample lacking fluorine atoms, hydroxyapatite and octacalcium phosphate were detected. With addition of fluorine within the structure of precipitated minerals, morphology of minerals was dramatically changed from oriented rod-like minerals with rectangular cross section toward spherical particles consisting of smaller crystals with uneven surface scattered over the gelatinous bulk material.
Journal of biomedical materials research. Part B, Applied biomaterials, Jan 20, 2017
Decellularized extracellular matrices (ECM) based materials are routinely used for a variety of c... more Decellularized extracellular matrices (ECM) based materials are routinely used for a variety of clinical applications. Hereof, in vivo application of decellularized ovine small intestinal submucosal (DOSIS) layer as, a scaffold is yet to be investigated. In this study, the effectiveness of the DOSIS scaffold, with or without rat bone marrow mesenchymal stem cells (BM-MSCs), in full-thickness wound healing of critical-sized defect was experimentally studied in a rat model. The experimental groups included; group I (control), group II (DOSIS), and group III (BM-MSCs-seeded DOSIS). Wound healing of all groups was examined and compared clinically and histopathologically on days 7, 14, and 21 postoperation. Our results represented BM-MSCs-seeded DOSIS accelerated wound contraction and healing compared to both the DOSIS alone and control groups. Epithelization was close to completion 21 days postoperation in DOSIS alone. In OSIS with BM-MSCs group, epithelization was faster and had fully ...