The effect of sub-epineural platelet-rich plasma (PRP) on regeneration of the sciatic nerve in a rat model

Background: Peripheral nerve injury is one of the most challenging of modern surgical problem. Recent advances in understanding the physiological and molecular pathways demonstrated the important role of growth factors in peripheral nerve regeneration. Platelet-rich plasma (PRP) is a biological product that has many growth factors. The aim of this study was to investigate the effect of PRP in the regeneration of sciatic nerve crush in the rat model. Methods: In this experimental study that established in the animal lab of the Hazrat Fatemeh Hospital in Tehran from September to October 2013, Twenty-four healthy male Sprague-Dawley rats (200-250 g) were randomly divided into two groups. In all rats the sciatic nerve was cut and then carefully repaired by the tension free method under a light microscope. In group 1, after the repair, 0.05 μL of PRP was injected below the epineurium to the proximal and distal parts of the repaired area. In group 2 the same amount of normal saline was injected to the proximal and distal of the repaired area. After six weeks footprint analysis, neurophysiologic and histopathology evaluations were performed. Results: Significant differences existed between the two groups footprint analysis (P= 0.001). Also the nerve conduction latency test was significantly shorter in PRP group. (1.0233 ms in PRP group and 1.7375 ms in control) (P< 0.001). The average amplitude in the first group and the second group was 7.6250 mv (control) 6.3667 mv that does not show a statistically significant difference (P= 0.093). Significant differences between the two groups in the number of axons of the proximal portion of the study was not seen (P= 0.29). The parameters included number of axons of the proximal and the distal part of axons, the diameter of the distal and proximal axons in the two groups were compared. In the two groups there was statistically significant difference between the above parameters. (P= 0.298). Conclusion: It seems that PRP may have an important role in peripheral nerve regeneration and functional recovery after nerve laceration and repair. Further clinical evaluation recommended. © 2016, Tehran University of Medical Sciences. All rights reserved

Assessing effect of three herbal medicines in second and third degree burns in rats and comparison with silver sulfadiazine ointment

Introduction Assessing effect of three herbal medicines on healing of deep second and third degree burns in rats and their comparison with silver sulfadiazine group. Methods and materials 40 rats were randomly assigned to one of the four groups, each group 10 rats. A deep second degree burn and a third degree burn were induced on the lower back and upper back of each rat under standard burning procedure, respectively. The burns were daily dressed with Robacin in group 1, silver sulfadiazine in group 2, aloe vera extract in group 3, and Rimojen in group 4. Responses to the treatment were assessed by digital photography during the treatment until day 32. Histological parameters (PMN, epithelialization, fibrosis, and angiogenesis) were assessed after the scar biopsy at the end of the research. Results On the basis of the taken photos, the wound had better healing in Robacin group. Also, speed of healing was better in aloe vera group than silver sulfadiazine and Rimojen groups. In terms of wound surface area maximal improvement was observed at the same time in the second and third degree burn wounds in Robacin group, in the second degree wound of aloe vera and Rimojen groups, and in the third degree wound of aloe vera and silver sulfadiazine groups. In pathological respects, epithelialization was more evident in both wounds of aloe vera group and third degree burn of Robacin group. In both wounds of Robacin group (second and third degree), the extend of angiogenesis and fibrosis was significantly less than other groups; but, inflammation was at a less level in third degree of silver, second degree of Rimogen and aloe vera, and third degree of aloe vera groups. Conclusion In histological survey, minimal rate of angiogenesis and fibrosis was seen in Robacin group, which indicated less wound scar in this group. Healing speed of the burn wound was also higher in Robacin group. © 2014 Elsevier Ltd and ISBI. All rights reserved

A comparison between occlusive and exposure dressing in the management of burn wound

Background and aim Two types of dressing, occlusive and exposure dressing, are commonly used in burn units. A dressing is said to be occlusive if a moist wound surface is maintained when the dressing is in place. This study was designed to compare the effectiveness of occlusive and exposure dressing in controlling burn infections. Patients and methods Two hundred patients with second-degree burns admitted to Mottahari Hospital, Tehran, Iran, over a period of 12 months from May 2012 to May 2013 were studied. They were divided into two groups of 100 each, to receive either occlusive or exposure dressing. During the first week of treatment, wound specimens were obtained by sterile swab and cultured in selective media. Demographics (age and gender), burn areas, cause of burn, length of hospital stay (LOS), type of infections and time to total healing were compared between the two groups. Results Occlusive dressing was more susceptible to microbial contamination and infections than exposure dressing. The mean duration of treatment based on epithelialization and healing in occlusive dressing was longer than for exposure dressing. The most common isolate was Pseudomonas spp., followed by Enterobacter, Escherichia coli, Staphylococcus aureus, Acinetobacter, and Klebsiella spp. Conclusions Exposure dressing was more suitable than occlusive dressing for treating partial-thickness at our center. Pseudomonas aeruginosa was the most common organism encountered in burn infection. © 2015 Elsevier Ltd and ISBI. All rights reserved