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Showing 8 results for Scaffold
Ramin Khajavi, Maryam Hajmaleki, Farhad Shahmirzaei Ashtiyani, Tayebeh Toliat, Morteza Sattari, Mohammad Mirjalili,
Volume 23, Issue 3 (9-2013)
Background: When hydrocolloids dressings are loaded with an antibacterial agent, they can also prevent infection during wound cicatrisation. To consider interesting properties of traditional Gum Tragacanth such as moisture absorption, hydrocolloid formation, drug holding and releasing abilities, it was aimed to introduce a scaffold wound dress based on Gum Tragacanth with drug release ability simultaneously.
Materials and Methods: In this experimental study, gum tragacanth from Astragalus gossypinus species (Iranian species) is solved and loaded with an aminoglycoside antibiotic (Gentamicin). Prepared solution transformed to a nano fibers network “scaffold” by lyophilization method. Samples were characterized by scanning electron microscopy, fourier transform infrared and X-ray diffraction methods and their antimicrobial and moisture holding properties were determined.
Results: Gum tragacanth showed a proper potential for dispersing gentamicin and the drug was loaded into polymer matrix without any aggregation. Loaded gum tragacanth with gentamicin is successfully transformed to a nanofibers scaffold by lyophilization. The diameters of fibers were in the range of 300nm to 2µm. Transformed gum tragacanth into scaffolds showed declined regain content (up to 50%) due to the ordering and orientation of polymer chains. Ordered hydroxyl groups also observed in FTIR graphs. Regarding the zones of inhibition, scaffolds also showed acceptable antibacterial activities.
Conclusion: Produced scaffolds are capable of absorbing wound’s exocrine liquid easily due to their high specific area of nanofibers. When it is turned to gel by moisture sorption, the release of loaded Gentamicin would be enhanced.
Mohammad Reza Noori -Daloii, Fatemeh Alizadeh,
Volume 24, Issue 2 (6-2014)
Schizophrenia is a severe psychiatric disorder that has a lifetime prevalence of ~1% in the most studied population. Schizophrenia is a multifactorial disorder that is characterized by the contribution of multiple susceptibility genes that could act in conjunction with epigenetic processes and environmental factors. Linkage and association studies have shown a number of candidate risk genes including Nerugulin 1, Disrupted in schizophrenia, Disbyndin and Epsin 4 that have associated with schizophrenia. However, their biological function remains elusive. ‘Disrupted in schizophrenia 1’ (DISC1), a gene locus originally identified at the first in a large Scottish family, showing a heavy burden of major mental illnesses associated with a balanced t(111)(q42.1q14.3) chromosome translocation. Substantial genetic and biological research on DISC1 has been displayed in past decade that DISC1 is now recognized as a genetic risk factor for a spectrum of psychiatric disorders and it impacts on many aspects of central nervous system (CNS) function, including neurodevelopment, neurosignaling, and synaptic functioning. Evidences emerged from genetic studies have shown a relationship between DISC1 and quantitative traits, including working memory, cognitive aging, gray matter volume in the prefrontal cortex, and abnormalities in hippocampal structures as well as function. DISC1 interacts with numerous proteins, also involved in neuronal migration, neurite outgrowth, cytoskeletal modulation, and signal transduction, some of which have been reported as independent genetic susceptibility factors for psychiatric morbidity. Here, we studied association of genetic variants of several susceptibility genes to schizophrenia, specially DISC1 and its intractor proteins and their effect on functional and structural of the brain in human and in the mouse.
Elham Hoveizi, Kazem Parivar,
Volume 25, Issue 1 (4-2015)
Background: The rat pheochromocytoma cell line (PC12) differentiates and converts into neuron-like cells in in vitro condition under inductive factors. Researchers have shown that different growth factors, like neurotrophic growth factor (NGF) and basic fibroblast growth factor (bFGF), have different effects in proliferation, survival and differentiation of the cells. It was hypothesized that porous biodegradable polymer scaffolds support the formation of complex 3D tissues during differentiation of PC12 cells. The aim of this study was to evaluate the role of nanofibrous scaffold PCL/gelatin on neuronal differentiation of PC12 cells.
Materials and methods: In this basic study the PC12 cells were seeded on PCL/gelatin under identical media and growth factor supplementation conditions. Gene expression including Nestin and Map2 (Microtubule-associated protein 2) was analyzed using quantitative RT-PCR and immunostaining. Cellular morphology was analyzed with light microscopy sphere ultra structure was analyzed with scanning electron microscopy.
Results: PC12 cells could efficiently differentiate into neuron-like cells on 3D culture and PCL/gelatin scaffold had no adverse effect and toxicity on PC12 cells.
Conclusion: Using tissue engineering provides a potential mechanism for creating viable human neural tissue structures for future therapeutic applications in neural pathologies such Parkinson’s disease, spinal cord injury, and Glaucoma.
Maryam Hajmaleki, Ramin Khajavi, Tayebeh Toliyat,
Volume 25, Issue 1 (4-2015)
Background: As cytotoxicity and antibacterial properties are considered as two essential factors for advanced wound care dressings, many attempts have been made to introduce and apply potent substances to provide these requirements. In this study, keratin as a valuable substance extracted of human hair waste and fabricated to a nanofibrous scaffold for achieving to least cytotoxic and improved antibacterial properties.
Materials and Methods: Keratin was extracted of human hair waste by an alkaline method and it was characterized by SDS-PAGE electrophoresis method. Extracted keratin was accompanied in different concentrations with PVA and silver nanoparticles and then fabricated into nano-fibrous scaffold through electrospinning method. Fabricated scaffolds were investigated and compared by scanning electron microscopy, measuring antibacterial activity (AATCC Test method 100-2004) and MTT assay (directly and by ISO 10993-5 standard method).
Results: Keratin with molecular masses of 56—65 kDa observed in the extracted substance. 3D scaffolds of nanofibers with diameter between 90-180 nm fabricated with different concentrations of kertain successfully. With the increase in keratin concentrations in fabricated scaffolds, their antibacterial activity against both Escherichia coli (ATCC8793) and Staphylococcus aureus (ATCC6538) bacteria were improved significantly. Furthermore, incorporating of keratin caused improved cell viability about 21% more in compare with the control sample.
Conclusion: Valuable keratin was obtained from an economical source with an alkaline method. Beside the intrinsic and proven properties of keratin such as compatibility with human skin, introducing this substance to nanofibrous scaffolds caused improved antibacterial properties and cell viability making it as a potent candidate for advanced wound caring purposes.
Mohammad Reza Noori-Daloii, Yeganeh Eshaghkhani,
Volume 25, Issue 2 (6-2015)
In mammals, the majority of products of gene expression are non-coding ribonucleotide sequences. They include short and long RNA molecules with sizes ranging of tens to hundreds of nucleotides. Among them, the molecules with more than 200 nucleotides are called long non-coding RNAs or lncRNAs. While LncRNAs functions depend on their unique molecular structures, they play important roles in regulating gene expression at epigenetic, transcriptional and post-transcriptional levels. Interacting with other biological molecules such as DNA, RNA and protein, LncRNAs have been found to play important roles in normal cell physiological activities. Activation of transcription factors, guidance of ribonucleoprotein complexes, aggregation of partner proteins, regulation of alternative processing, cooperation in chromatin remodeling, facilitation of genomic imprinting, maintaining of multipotential state and control of nucleus/cytoplasm traffic are some of crucial approaches Implemented by LncRNAs. Modern technologies have been developed to identify lncRNA molecules, and many relevant databases have been designated to facilitate research and academic exchange of data concerning them. In this review article, signification, identification, classification, biological evolution, genomic position, configuration, expression, localization and remarkable functions of LncRNAs have been discussed.
Keywords: ncRNA, lncRNA, Function.
Mohammad Reza Noori-Daloii, Yeganeh Eshaghkhani,
Volume 25, Issue 3 (9-2015)
Cancer is a complex condition in which gene expression is disrupted. Genetic factors involved in cancer pathology have been studied significantly. However, evidences have documented that a considerable fraction of susceptibility to cancer is not attributable to changes in protein coding sequences. Discovery and identification of a vast repertory of long noncoding RNAs (lncRNAs) with more than 200 nucleotides in human have been associated to unveiling their roles in tumorigenesis. Importance of lncRNAs, as either tumor suppressive or oncogenic agents, has been demonstrated in various common cancers. Recent studies indicate that several risk loci contributing to cancer pathogenesis are transcripted to lncRNAs which have critical roles in cancer incidence. Fundamental mechanisms of lncRNAs functions in a variety of gene expression levels involving epigenetic modification and transcriptional or post-transcriptional regulation, as well as interaction of these RNAs with other critical molecules such as DNA and some of proteins with definitive roles in cell fate have been described previously in detail by authors. Since a remarkable part of cancer pathogenesis has been reported in related to lncRNAs, the current review article discusses about association of some lncRNAs with specific tumors, effects of lncRNAs on cancer incidence and their importance in providing diagnostic and prognostic opportunities.
Keywords: ncRNA, lncRNA, Cancer, Diagnosis, Prognosis.
Elham Hoveizi, Tayebeh Mohammadi,
Volume 26, Issue 3 (9-2016)
Background: Human induced pluripotent cells (hiPSCs) could be established as promising new resources for obtaining differentiated cells for cell therapy. iPSCs have the potential to use as multipurpose research and clinical tools to understand model diseases, develop and screen candidate drugs, and deliver cell-replacement therapy to support regenerative medicine. Here, we demonstrated the ability of human iPSCs to differentiate into adipocyte and osteoblast fate.
Materials and methods: In this experimental study, human iPSCs were culture-expanded. HiPSCs were then cultivated in the osteogenic and adipogenic conditions for 21 days after which differentiations were evaluated by specific staining as well as qRT-PCR analysis for related gene expression.
Results: In osteoinductive cultures, the cells formed nodules which were positively stained red following alizarin red staining. In adipogenic cultures, the cells developed some lipid droplets which were positively stained red with oil red. According to qRT-PCR analysis, the bone-related genes including osteocalcin and osteopontin, and also the adipocyte-specific genes such as PPAR and LPL were expressed in the osteogenic and adipogenic cultures, respectively.
Conclusion: Taken together, hiPSCs are pluripotent cells with the ability to differentiate into osteocytic and adipocytic cell lineages.
Keywords: Differentiation, Induced pluripotent stem cells, Bone and adipose cells.
Homayoun Jalali Tafti, Mehrdad Hashemi, Khalil Alimohammadzadeh,
Volume 29, Issue 3 (9-2019)
Background: Colorectal cancer is one of the main causes of cancer death and the third most common malignant cancer worldwide. FGF14 is a member of the large family of fibroblast growth factors. These factors control a wide range of biological functions, including cell proliferation, survival, migration and differentiation that disturbing their expression can lead to cancer. The purpose of this study was to determine the expression of FGF14 in colorectal cancer tissue samples and adjacent healthy tissues.
Materials and methods: In this case-control study, 35 patients with colorectal cancer and adjacent tumor tissue were classified based on their clinical and pathological characteristics. The expression was studied by real time PCR reaction method.
Results: The relative expression levels of FGF14 in tumoral tissues were shown to be significantly increased compared with their adjacent normal tissues. There was significant correlation between the relative expression level of FGF14 in tumoral tissues and clinicopathological features, such as cancer staging, tumor size, and metastasis.
Conclusion: Increased expression of FGF14 in colorectal cancer tissue compared to the adjacent normal tissues is associated with the cancer progression and development relevant clinicopathological features. Therefore, it may play an important role in the pathophysiology of colorectal cancer.