ABSTRACT
Stem cells are applied in the treatment of wide range of diseases and can be separated from different tissues of the body. These cells can treat diseases by cytokine and growth factor secretion and also cell differentiation. Burn wound is a challenging problem of reconstructive surgery and stem cells may help wound healing process. We designed this study to evaluate the beneficial effect of fat derived stem cells for coverage of 3[rd] degree burn wound. This study was experimental and has been done in Burn Research Center of Iran University of Medical Sciences during January 2012 to April 2013. Thirty rats randomly divided to three equal groups. Inguinal fat of 10 rats [one group] were used for preparation of autologous adipose-derived mesenchymal stem cells. Acellular amnion was used as a scaffold for stem cell transfer. Each of the thirty rats had been exposed to a cm deep 3rd degree burn on back area. 24 hours after surgery, the wound was excised and it had been covered by three conventional dressing in the first group, acellular amnion in the second group and acellular amnion seeded with adipose-derived stem cell in the third group. The rate of wound healing and pathologic characteristics was compared in all three groups. Healing rate and decrease in wounds size was significantly better in acellular amnion seeded with adipose- derived stem cells compared with other two groups at 3[rd] and 15[th] days after surgery P<0.01. Also in histopathology examination, fibroplasia and neovascularization of wounds were significantly better in stem cells group than the other two groups P<0.001. Acellular amnion seeded with adipose-derived stem cell can result in faster wound healing and better histopathology characteristic. The amnion as a scaffold and the fat derived stem cells as healing accelerator are recommended for coverage of the 3rd degree burn wounds after excision and it may reduce the need for skin graft
ABSTRACT
Necrosis of skin flaps is considered as an important complication in reconstructive surgery. We conducted an experimental study to investigate the efficacy of low-molecular weight heparin, clopidogrel and their combination to improve the flap survival. Forty male, adult Sprague-Dawlay rats were divided randomly into 4 groups. Standard rectangular, distally based dorsal random pattern skin flap was elevated. To prevent the graft effect, a sterile sheet was put under the flap. No pharmacological agent was administered for the control group. In group 2, single subcutaneous dose of enoxaparin [3.2 mg/kg] was immediately administrated after surgery. In group 3, clopidogrel [25 mg/kg] was given orally for 7 days. In group 4, both enoxaparin and clopidogrel were administrated. The rats were evaluated on post-operative day 7 for viable and necrotic portions of flaps. The mean and SD of necrosis was 17.79 +/- 2.5 cm in the control group, 16.20 +/- 3.1 cm in low-molecular weight heparin, 15.25 +/- 3.8 cm in combined therapy group and 13.69 +/- 2.7 cm in clopidogrel group. Clopidogrel was the only pharmaceutical agent that produced a significant increase in the flap survival area. Clopidogrel may be an effective pharmaceutical agent that significantly increases viability of random skin flaps in rats, but low-molecular weight heparin and their combination did not have any significant beneficial effects
ABSTRACT
Although, different studies on end-to-side nerve repair, results are controversial. The importance of this method in case is unavailability of proximal nerve. In this method, donor nerves also remain intact and without injury. In compare to other classic procedures, end-to-side repair is not much time consuming and needs less dissection. Overall, the previous studies in this field have just evaluated nerve recovery by non functional or functional parameters. As it has proven, the results of functional and non functional studies are not always matched. Therefore, this study was designed to evaluate this method by functional [Sciatic function index] and non functional parameters [histochemical study]. In this experimental study, forty adult male Wistar rats [200-250g] were used their left proneal nerve was cut and divided into four groups: 1- control group [n=10]. In this group, nerve was exposed and cut and implanted onto adductor muscles, 2- end-to-end anastomosis [n=10]. In this group, peroneal nerve cut and two segments were anastomosed end-to-end, 3- end-to-side anastomosis with window [n=10]. In this groups, peroneal nerve was cut and anastomosed with window to tibial nerve, 4- end-to-side anastomosis without window [n=10]. In this group, peroneal nerve was cut and anastomosed without window to tibial nerve. After 1, 8 and 16 weeks, functional [Sciatic function index] and after 16 weeks non functional studies [histochemical study] were performed and the results compared. All experimental groups [group 2,3,4] motor recovery at 8th, 16[th] week were not statistically different [p>0.05]. In histological recovery with end to end neuroraphy in rat model. Due to the fact that the diameter of nerves and muscles which might be neurotised in human are much bigger and not comparable with rat, it is suggested to set up some set of experiments on the bigger size animals such as primates in further studies for generalization of results to human being
ABSTRACT
In the bone marrow, there are certain populations of stem cell sources with the capacity to differentiate into several different types of cells. Ideally, cell transplants would be readily obtainable, easy to expand and bank, and capable of surviving for sufficient periods of time. Bone marrow mesenchymal stem cells [BM-MSCs] possess all of these characteristics. One of the most important benefits in using BM-MSCs is the possibility of autologous therapy. Recently, numerous studies have evaluated strategies that attempt to promote axonal regeneration in central nervous system [CNS] injuries. Among these strategies, cell transplantation is considered to be the most effective way. The differentiation of stem cells into different neural lineages [such as astrocytes and neural like cells] before transplantation has a critical role in achieving the best results in studies of CNS injury. In this study, BM-MSCs were isolated from bone marrow aspirates taken from the femurs of 103 live rats. The detection of BM-MSCs was performed with RT-PCR analysis, and they were then induced to differentiate into neuron-like cells in serum-withdrawal medium over a two week period using a multistep protocol. In addition to the morphological evaluation of differentiated cells, the process of neural differentiation was proven by immunocytochemical techniques using primary antibodies to Neuron Specific Enolase [NSE] to assess cell differentiation. PT-PCR analysis was performed for the evaluation of neural specific genes, which included NSE, MAP2, nestin, and beta-tubulin. Morphological evaluations detect neuron like cells with longitudinal processes. Using RT-PCR and immunocytochemistry assays, neuron specific genes and proteins following treatment of cells in serum-withdrawal induction medium was expressed. This study showed a simple and practical method for differentiating MSCs into neuron like cells, and feasibility of aspirate bone marrow from a live rat for autologous grafting