Modares Journal of Biotechnology

Abstract Fibrinogen is a major component of the coagulation cascade following tissue damage and rapidly forms an insoluble fibrin scaffold. Fibrin is a filamentous biopolymer that naturally forms from fibrinogen polymerization during blood clotting. After tissue damage and coagulation cascade initiation, soluble fibrinogen polymerization by thrombin enzymebegins and forms an insoluble fibrin network and blood clots with platelets. This fibrin network is crucial for the development of homeostasis after tissue damage. This biopolymer also plays a key role in the wound healing as a temporary scaffoldand due to its unique structural properties and physiological function; it is used in reconstructive medicine. Fibrin is able to absorb extracellular matrix proteins (ECM) such as fibronectin and growth factors. The main types of fibrin scaffolds like platelet-rich fibrin (PRF) and platelet-rich plasma (PRP) are being used as autologous biomaterials in reconstructive medicine, wound healing, orthopedics and skin reconstruction and cosmetic sciences. Fibrin derivatives and degradation products also play an important role in the process of wound healing by stimulating cell infiltration and tissue regeneration and they are being widely used in developing new products as a biological material for over a century.

Abstract Datura (Datura stramonium) is known as a rich source of tropane alkaloids, including scopolamine and hyoscyamine as parasympatholytics that competitively antagonize acetylcholine. Production of secondary metabolites often occurs in plants against the various elicitors or signal molecules. In this study, the effect of yeast extract as a biotic elicitor on tropane alkaloid production was evaluated. Surface-sterilized Datura seeds were cultured on 1/2 MS medium supplemented with different concentrations of yeast extract (0, 1.5, and 3g/L). One month after germination, alkaloid yield of Datura plantlets was measured by the use of High-Performance Liquid Chromatography (HPLC). Also, total protein content and antioxidative enzymes activity were determined by spectrophotometry method. According to the results, the fresh weight of root and shoot parts of Datura plantlets at 1.5g/L yeast extract was increased about 2 and 4 times, respectively. Yeast extract (1.5g/L) caused to 1.7 times increase of hyoscyamine amount of root and shoot parts and 2.5 folds scopolamine of Datura plantlets. Moreover, on yeast extract (1.5g/L)-treated plantlets, total protein content, and activity of catalase and guaiacol peroxidase were almost the same as the control group. Altogether, yeast extract (1.5g/L) can be used as a good candidate for enhancement production of tropane alkaloids especially hyoscyamine and scopolamine with high medicinal value.

Abstract Abstract:

Aptamers are single-stranded sequences of RNA, DNA, or highly specific proteins that tend to bind to a wide range of target molecules. Aptamers are widely used in various fields, especially medicine and diagnostics, and are similar in their application to antibodies. There are many benefits to using aptamer instead of antibodies, such as low cost, longer life, increased tissue permeability, and more. There are several methods for producing aptamer that in silico methods can shorten and simplify the steps of aptamer production. With aptamer modeling, a set of in silico methods such as modeling, docking, and molecular dynamics can be used to screen for the best aptamer sequence. In this article, a review of the types of aptamers, their structure and design methods in silico is briefly stated.

Keywords: Aptamer, DNA, RNA, Protein, insilico



Keywords: Aptamer, DNA, RNA, Protein, insilico

Abstract Nanotechnology involves technological research and development in spaces at the range of 1 to 100 nanometers, and in this technology, very small and atomic scale particles are created and handled. Plant extracts can be used as a green method for the synthesis of silver nanoparticles. In this study, the biosynthesis of silver nanoparticles was performed using extracts of sesame (Sesamum indicum) seeds. Silver nitrate was added to the seed extract, and then it was incubated at 30 ° C. The effects of three concentrations (1mM, 2mM and 3mM) of silver nitrate on the synthesis of silver nanoparticles were studied. The analyses of absorption spectroscopy UV-Visible, Transmission Electron Microscopy (TEM), X-ray Diffraction (XRD) and Inductively Coupled Plasma (ICP) were conducted to assess the production of nanoparticles. UV-Visible spectroscopy analysis and the peak at 420 nm indicated the occurrence of nanoparticles in the extract. TEM image determined that the nanoparticles were spherical with average size of about 14 nm. XRD analysis showed the nano-crystals synthesized by the extract, and Inductively coupled Plasma (ICP) determined the conversion percentage of silver ion into silver nanoparticle as approximately 99.61 percent.

Abstract Today, the engineering of bone tissue has created special solutions to restore bone tissue by combining biological materials with a scaffold to provide cells suitable for bone formation and growth factors. In this research, a fusion peptide was designed with bioinformatics methods that can bind to the growth factors involved in bone tissue repair and lead to the trapping of these factors in the lesion site. In this study, heparin-binding domain was placed in the designed peptide and this peptide was complexed with growth factor in monomer and dimer forms with the help of docking. The structures of the complex were selected based on the lowest scores obtained, which included -912.5 and -1117, respectively. According to the results of docking and molecular dynamics simulation, this fusion peptide was able to bind to the growth factor of bone morphogenetic proteins. Based on the results of the simulation, unlike the peptide in the monomer state, the changes in the RMSD diagram of the peptide complex in the dimer state became stable after 10 nanoseconds from the simulation time and remained stable until the end of the simulation. These results show that the resulting complex in the dimer state has a better pattern of stability compared to the monomer state according to the investigation of the RMSD factor.