Antioxidant and toxicity studies of biosynthesized cerium oxide nanoparticles in rats

Funding Information: We would like to thank the Vice Chancellery for Research and Technology, MUMS for financial support (grant no 930954) and facilities.Peer reviewedPublisher PD

The importance of fibronectin in development, regeneration and treatment: review article

Fibronectin (FN) is one of the essential component of the extra cellular matrix and their important role is as regulator of cellular activities and also fibronectin is an important scaffold for maintaining tissue. Fibronectin conformational changes expose additional binding sites that participate in fibril formation and in conversion of fibrils into a stabilized, insoluble form. In fact fibronectin is a connected glycoprotein disulfide dimer with sedimentation coefficient of approximately S 13 and 440 kDa molecular mass which is exist in many extracellular matrix and plasma with concentration of approximately 300 µg/ml that during the regeneration body tissues acts in severely regulated stages until regenerate the damaged tissue. Fibronectin has domains for interacting with other extra cellular matrix proteins, cell surface receptors, glycosaminoglycans (GAGs), and other FN molecules. This combination of domains allows FNs to bind simultaneously to cells and to molecules within the surrounding matrix. Also fibronectin have binding sites for collagen/ gelatin, heparin, fibrinogen, and other molecules. In the present study important roles of fibronectin in development, regeneration especially in nerves system and important role of it in treatment of some diseases have been reviewed. Present study has reviewed 77 publications by using of PubMed, NCBI, Elsevier, EBSCO and Nature databases for describing the important roles of fibronectin in biological systems. Studies have shown that fibronectin has diverse roles such as: cellular adhesion, embryonic differentiation, assembly of extra cellular matrix, connecting and cell growth, transformation as well as cell migration that each of this roles depends to fibronectins action site. Considering the important role of fibronectin in attachment of cancer cells to basal lamina, spread neoplasm, tissue regeneration and formation of extra cellular matrix better identification the properties as well as physiological applications of fibronectin in tissues and bodies of animals can provide the better understanding of physiological mechanisms and pathophysiological effects of cells on each other, and also provides the new ways for treatment a variety of diseases

Effects of Dexamethasone on Regeneration Process after Sciatic Nerve Transect and Acellular Scaffold Graft in a Rat Animal Model

Introduction: Peripheral nervous system has an innate regenerative ability, and in severe injuries leading to nerve destruction, repair does not occur spontaneously and medical intervention is required. In this regard, dexamethasone is one of useful drugs prescribed for neurological recovery after spinal cord injury. The objective of the present study was to assess the effect of dexamethasone on functional recovery and histological changes following sciatic nerve transect and regeneration with the acellular scaffolds in male Wistar rats.   Materials & Methods: Fifty male Wistar rats were randomly divided into five groups of 10. The groups included: negative control group(left sciatic nerve was transecte), sham-operated group) surgical procedure without the nerve transect ), and experimental groups 1 and 2 (sciatic nerve was transected and regenerated with acellular nerve scaffold) treated with 1 and 2 mg/kg of dexamethasone, respectively. Experimental group 3 (sciatic nerve was transected and regenerated with acellular nerve scaffold) was injected with vehicle. Then, 1 cm of left sciatic nerve was exposed and replaced with a piece of scaffold. Behavioral, electrophysiological, and morphological alterations were evaluated during the experiment.   Findings: with dexamethasone in comparison with the control group (P < 0.05). Analysis of gastrocnemius muscle mass in groups treated with dexamethasone in comparison with negative control group showed that muscle atrophy was reduced; also the dexamethasone-treated group presented significantly greater nerve fiber, axon diameter, and myelin sheath thickness (P < 0.05).   Discussion & Conclusions: The results showed that the administration of dexamethasone after sciatic nerve transects and grafting the acellular scaffold increased motor function in a rat animal model