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ABSTRACT: Introduction & Objective: Much interest has been focused on the development of alternative instrument for bridging the nerve gaps. In the present study we used poled polyvinelidene fluoride (PVDF) tube filled with nerve growth factor (NGF) and collagen gel as a substitute for nerve autograft and compared the results with other current surgical techniques. Materials & Methods: In this experimental study, 40 male Wistar rats each weighing 200-250 g were randomly divided in five groups nerve guidance channel, autograft, epineural suture, axotomy and sham operation. In nerve guidance channel groups, a 10 mm piece of left sciatic nerve was transected and this gap was repaired by PVDF tube containing NGF 7s (100 ng) and collagen gel (1.28 mg/ml). In autograft group, the 10 mm piece was 180° rotated and sutured to two nerve ends. In epineural suture group, left sciatic nerve in the middle thigh was transected then sutured end to end. In axotomy group, left sciatic nerve was transected in the middle thigh and was not repaired. After two months, left ventral L4-6 segments of spinal cord was removed and semi-thin and ultra-thin preparation for light and electron microscope were done. Contra-lateral side of spinal cord segments was used as control in all groups. Results: After two months we observed motor neuron atrophy and shrinkage, cytoplasmic vacouels and piknotic neurons in different surgical groups, but it was more intense in axotomy group. These changes were less in epineural suture group than in autograft and nerve guidance channel groups. In sham and control groups no changes were observed. In addition, increased nuclear condensation, nuclear membrane folding, central and marginal chromatin clumping in spinal motor neuron were observed in surgical groups mainly in axotomy group. Conclusion: According to the results, any type of injury to the sciatic nerve can cause cell changes and finally cell death in the spinal motor neurons. Using PVDF with NGF and collagen gel reduced cell changes at the level of autograft.

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Background & aim: The Covid-19 pandemic has presented the world with a wide array of economic, social, political, and health problems. Therefore, providing people with correct and timely information can significantly help disease management and reduce death cases. The present study aimed to assess the epidemiology of Covid-19 in Kohgiluyeh and Boyer-Ahmad Province. 

Methods: The current study descriptive study of the epidemic trend was carried out in 2022. The data was collected by reviewing the valid information collected in the academic headquarters of the control of Kogilouye and Boyer Ahmad province, Iran, and the systems related to this disease in the period of 33 months after the first confirmed case of the disease was identified in the province. The collected data were analyzed using descriptive statistics including mean and frequency percentage.

Results: With the removal of travel restrictions, there was an increase in disease cases in the province. The incidence rate and percentage of positive Covid-19 cases in Kohgiluyeh and Boyer-Ahmad province were much higher than the national average. The highest percentage of positive rate in the samples was associated to the month of November 2019 with 56.59% nonetheless the percentage of case fatality rate caused by the disease in the province is lower than the national average (.86 against 1.91 percent). The percentage of Covid-19 related deaths in the province was lower than the national average. At the same time, with an increase in vaccination coverage and the percentage of infection in the province, a decrease in cases of infection, hospitalization, and Covid-19-related death were observed. The comparison of the first and last peaks of the disease in the province demonstrates the marked effect of vaccination.

Conclusion: Encouraging and persuading the community about the importance of vaccination, especially the third round and also the injection of the fourth dose of the Covid-19 vaccination, with the priority of health system personnel and people with underlying diseases, using the capacity of other institutions and organizations, especially the radio and television of the provincial capital is the safest and most optimal means of protection against infection, hospitalization and death caused by Covid-19.