Abstract
Background: The purpose of the present study is to investigate the effect of 8 weeks High-intensity Interval Training (HIIT) on the expression of two muscle growth regulating genes (myostatin and follistatin) in gastrocnemius muscle of healthy male rats.
Materials and Methods: 16 male Wistar rats were randomly divided into two groups in the same number: control and HIIT. HIIT program was underwent 40 min each session, three sessions in a week for eight weeks. Each exercise training session consisted of 5 min warm-up and cool-down at 40-50 % VO2max, 30 min interval running including 4 min high-intensity (85-90% VO2max) and 2 min active recovery (at 50-60% VO2max). Rats in control group did not do any exercise training program. 48 h after the last training session, rats` gastrocnemius muscle was extracted and the expression of myostatin and follistatin genes was determined by Real Time-PCR. For statistical data analysis, independent t-test was used.
Results: The expression of myostatin was significantly reduced 68% in HIIT group in comparison with the control group (p<0.05). However, there was no significant difference in follistatin expression in HIIT group compared to the control group (p>0.05). Gastrocnemius muscle weight was significantly increased 23% in the HIIT group compared to the control group (p<0.05).
Conclusion: Results indicated that HIIT lead to significant reduction in the expression of myostatin gene and increase in the weight of gastrocnemius muscle in rats.
 

Background and Aim: Since late 2019, with the emergence of a new type of coronavirus that causes a new respiratory disease called COVID-19, there have been many concerns about the spread of this disease and how to deal with it. Due to the ability of the virus to be transmitted rapidly, diagnosing the infected individuals in the early stages for isolating them is critical. This study  aims to evaluate the reliability of Computed Tomography (CT) scan in diagnosing COVID-19.
Methods & Materials: Participants were 212 patients admitted to hospital with confirmed diagnosis of COVID-19. Demographic information, medical history, symptoms, and the chest CT scan results were collected and analyzed. Finally, the power of CT scans in the diagnosis of this disease was compared with the Real-Time Polymerase Chain Reaction (RT-PCR) molecular test.
Ethical Considerations: This study received ethical approval from the ethics committee of AJA University of Medical Sciences (Code: IR.AJAUMS.REC.1399.091).
Results: The sensitivity of CT scan in the diagnosis of COVID-19 was relatively high, but its false-positive results were also high.
Conclusion: CT scan is a relatively sensitive method for diagnosing COVID-19, but caution should be made due to its high false-positive results which can lead to increased financial burden on the health system.