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Objective: Multiple myeloma (MM) is an incurable plasma cell malignancy. Several genetic and epigenetic changes affect numerous critical genes expression status in this disorder. CDKN2A gene is expressed at low level in almost all cases with MM disease. The mechanism of this gene down-regulation has remained controversial. In the present study, we targeted EZH2 by microRNA-124 (miR-124) in L-363 cells and assessed following possible impact on CDKN2A gene expression and phenotypic changes.Materials and Methods: In this experimental study, growth inhibitory effects of miR-124 were measured by MTT assay in L-363 cell line. Likewise, cell cycle assay was measured by flowcytometery. The expression levels of EZH2 and CDKN2A were evaluated by real
Gum Arabic (GA) is a biocompatible polymer with the necessary requirements for a wound dressing. However, electrospinning of GA is a bottleneck due to its physico-chemical properties. The aim of this study was to fabricate an antimicrobial nanofibers mat from GA with suitable porosity, water absorption, water vapor permeability and mechanical strength. For this purpose, the composition of polycaprolacton (PCL)-coated GA-polyvinyl alcohol (PVA) nanofibers mat was optimized based on the possible highest porosity, water absorption and water vapor permeability, and then silver nanoparticles (AgNPs) loaded nanofibers mat was prepared based on this composition. The synthesis of AgNPs was supported by UV–vis and ICP analyses. The structure of ma
Large bone defects treatment is one of the challenges in current bone tissue engineering approaches. Various strategies have been proposed to address this issue, among which, pre‐vascularization by co‐culturing of angiogenic and osteogenic cells on the scaffolds can alleviate this problem. In the present study, modified fibrous scaffolds were prepared by electrospinning and subsequent ultrasonication of polycaprolactone (PCL) containing nano‐hydroxyapatite (n‐HA), with/without nano‐zinc oxide (n‐ZnO), and polyethylene oxide (PEO) as a sacrificial agent. The physical, mechanical and chemical characteristics of the scaffolds were evaluated. The results showed the presence of n‐ZnO, which in turn increased Young's module of the
Electrospun scaffolds are potentially interesting in bone tissue engineering due to a strong structural similarity to the natural bone matrix. To investigate the osteogenic behavior of cells on the scaffolds, dynamic culture of cells is essential to simulate the biological environment. In the present study, human mesenchymal stem cells (hMSCs) were cultured on multilayer nanohydroxyapatite-polycaprolactone electrospun scaffolds at different configurations (horizontal with or without pressure and parallel with the medium flow) and flow rates in a perfusion bioreactor. Alkaline phosphatase (ALP) activity, cell viability, Ca deposition and RUNX2 expression were determined in three different dynamic states, and compared with static culture afte
Genome-scale metabolic modeling has emerged as a promising way to study the metabolic alterations underlying cancer by identifying novel drug targets and biomarkers. To date, several computational methods have been developed to integrate high-throughput data with existing human metabolic reconstructions to generate context-specific cancer metabolic models. Despite a number of studies focusing on benchmarking the context-specific algorithms, no quantitative assessment has been made to compare the predictive performance of these methods. Here, we integrated various and different datasets used in previous works to design a quantitative platform to examine functional and consistency performance of several existing genome-scale cancer modeling a
Background:Nowadays, production of nanocomposite scaffolds based on natural biopolymer, bioceramic, and metal ions is a growing field of research due to the potential for bone tissue engineering applications.Methods:In this study, a nanocomposite scaffold for bone tissue engineering was successfully prepared using collagen (COL), beta-tricalcium phosphate (β-TCP) and strontium oxide (SrO). A composition of β-TCP (4.9 g) was prepared by doping with SrO (0.05 g). Biocompatible porous nanocomposite scaffolds were prepared by freeze-drying in different formulations [COL, COL/β-TCP (1: 2 w/w), and COL/β-TCP-Sr (1: 2 w/w)] to be used as a provisional matrix or scaffold for bone tissue engineering. The nanoparticles were characterized by X-ray
In the present study, an enzyme catalyzed in situ forming hydrogel based on chemically modified tragacanth was prepared and then evaluated for use in cartilage tissue engineering. For this purpose, firstly tyramine was conjugated on the galacturonic acid methyl ester units of gum tragacanth (GT) via ammonolysis of methyl ester groups in heterogeneous media. Then, the hydrogel was prepared by mixing of functionalized polymer, horseradish peroxidase (HRP) and hydrogen peroxide using a double syringe equipped with a mixing chamber. Then, cell viability of the encapsulated human mesenchymal stem cells (hMSCs) and in vitro chondrocyte differentiation of them, incubated in the presence of differentiation medium, were investigated. After mixing of
Today, cell therapy is known as an important tool in the treatment of chronic diseases where cells lose their normal function. Immunoisolation systems using microencapsulation or PEGylation have been developed to evade the problem of rejection by the immune system. The aim of the present study was to investigate a combination of microencapsulation and PEGylation methods in coating mouse embryonic stem cells (mESCs) to determine its effect in reducing the host’s immune response. Therefore, methoxy polyethylene glycol (mPEG) binding on alginate–trimethyl chitosan (TMC) microcapsules was investigated using FTIR. Furthermore, survival of the microencapsulated mESCs was confirmed using AO/PI staining and MTT assays. In addition,
Recombinant plasminogen activator (reteplase) is a third generation thrombolytic agent which has been used on coronary artery thrombosis and acute myocardial infarction. Clot lysis assay is usually considered as a unique method to evaluate biological activity of reteplase. In this study biological activity of reteplase was determined by APTT (activated partial thromboplastin time) lysis method. Validity of this method was evaluated in comparison with reference method, clot lysis time assay. Results of APTT lysis test showed good reproducibility (relative standard deviation (RSD) 3-5% for within day analysis and 4-7% for between day analysis), and accuracy (101.3-102.7%). APTT lysis responses were linear in range of 0.001-0.1 mg/mL reteplase
Nanocarrier-based drug delivery systems have been explored extensively in cancer therapy. Among the vast number of different nanocarrier systems applied to deliver chemotherapeutics to cancer tumor, intelligent systems which deliver drug to various sites in the body have attracted considerable attentions. Finding a specific stimulant that triggers the carrier to release its payload in the target tissue is a key parameter for efficacy of delivery systems. Acidic pH of cancer tumor helps a pH-sensitive carrier to release drug at the tumor site. In this study, a pH-sensitive mixed micellar system was developed using Dextran-Stearic Acid (Dex-SA) and Dextran-Histidine (Dex-His) conjugated polymers to deliver doxorubicin (DOX) to cancer cells. D
Miniaturized bubble columns (MBCs) have different hydrodynamics in comparison with the larger ones, but there is a lack of scientific data on MBCs. Hence, in this study, the effect of gas hold-up, flow regimes, bubble size distribution on volumetric oxygen mass transfer coefficient at different pore size spargers and gas flow rates in MBCs in the presence and absence of microorganisms were investigated. It was found that flow regime transition occurred around low gas flow rates of 1.18 and 0.85 cm/s for small (16–40 ?m) and large (40–100 ?m) pore size spargers, respectively. Gas hold-up and K L a in MBC with small size sparger were higher than those with larger one, with an increasing effect in the presence of microorganisms. A comparis
Background: Pancreatic islet transplantation is one of the most promising strategies for treating patients with type I diabetes mellitus.Objective: We aimed to assess the immunoisolation properties of the multilayer encapsulated islets using alginate-chitosan-PEG for immunoprotection and insulin secretion from the encapsulated islets induced under different glucose concentrations in vitro.Materials and Methods: In this study, the islets were isolated from Wistar rats. The biological function (insulin secretion) of the immunoisolated islets following to PEGylation and encapsulation in the alginate-chitosan-PEG, separately, in addition to their immuno-protection in a co-culturing with the lymphocytes isolated from the male C57BL/6 mice were i
Since the leading cause of death are cardiac diseases, engineered heart tissue (EHT) is one of the most appealing topics defined in tissue engineering and regenerative medicine fields. The importance of EHT is not only for heart regeneration but also for in?vitro developing of cardiology. Cardiomyocytes could grow and commit more naturally in their microenvironment rather than traditional cultivation. Thus, this research tried to develop a set up on-a-chip to produce EHT based on chitosan hydrogel.Micro-bioreactor was hydrodynamically designed and simulated by COMSOL and produced via soft lithography process. Chitosan hydrogel was also prepared, adjusted, and assessed by XRD, FTIR and also its degradation rate and swelling ratio were determ
One of the major problems associated with the electrospun scaffolds is their small pore size, which limits the cellular infiltration for bone tissue engineering. In this study, the effect of increasing the pore size on cellular infiltration was studied in poly/nanohydroxyapatite electrospun scaffolds, which were modified using ultrasonication, co‐electrospinning with poly (ethylene oxide), and a combination of both. Ultrasonic process was optimized by central composite design. The ultrasonic output power and time of the process were considered as the effective parameters. The pore size of the scaffolds was evaluated by scanning electron microscope. The optimum conditions, according to the pore area and mechanical properties of the scaffo
In this study, a method is proposed to reduce immunological response of immune system against Langerhans islets by PEGylation of islets combined with adjuvant therapy. For this purpose, the best composition for a mixture of succinimidyl valeric acid activated mPEG (mPEG-SVA) with different molecular weights (MWs) and for a mixture of succinimidyl carbonate activated mPEG (mPEG-SC) with different MWs was determined separately. Then, the effect of pentoxifylline (PTX) as an adjuvant drug on immunological response against PEGylated islets at best mPEG composition was studied. The extent of mPEGs reaction, the amount of interlukin-2 (IL-2) and perforin secretion, and the viability of lymphocytes and islets in homo and co-cultures in the presenc