مجله دانشکده پزشکی اصفهان
پیاپی 699 (هفته سوم بهمن 1401)

One of the major problems in old age is sarcopenia, which can be prevented by doing various exercise training. The purpose of the study was to investigate the effect of resistance and endurance training on the expression of genetic factors involved in muscle autophagy in elderly male rats.

In this study, thirteen male rats aged 18 months were randomly assigned to three groups: control (n = 10), endurance training (n = 10), and resistance training (n = 10). Training programs were done 5 sessions per week for 8 weeks. Then, all subjects were anesthetized 48 hours after the experiment finished and sampling was performed from the bicep. Then, the expression of AKT and FOXO3 genes was measured using the reference gene by Real-Time PCR method. Finally, statistical analysis was conducted using a one-way analysis of variance, and the pairwise differences were evaluated using Tukey's test.

The results of the analysis variance of FOXO3 and AKT proteins values showed that there is a significant difference between resistance, endurance, and control training groups respectively. Tukey's test for both proteins showed that there is a significant difference between resistance and control groups, and resistance training has a greater effect than endurance training.

Overall, the present study showed that resistance exercises in skeletal muscle can activate autophagy pathways more than endurance exercises. Therefore, resistance training seems to be a more effective training method in improving the expression of genes involved in advancing sarcopenia with aging.

Head and Neck cancers remain a significant problem due to their high morbidity and mortality and in most cases, require regional lymph nodes radiotherapy treatment. This work aims to evaluate and compare two methods of Three-Dimensional Conformal Radiation Therapy (3D-CRT) and Helical Tomotherapy (HT) based on treatment planning and selection of the most appropriate method to reduce side effects.

In this study, 20 patients with head and neck cancers were considered for treatment in the radiotherapy department of Seyed Alshohada Hospital, Isfahan, Iran. Two methods of HT and 3D-CRT were done using a 6 MeV photon energy apparatus and specific treatment planning algorithms. The dose-volume distribution curve (DVH), the dosimetric variables of the target organ, the radiation delivery efficiency, and the organs at risk were determined and results were compared with each other.

In HT the dose received by %95 planning target volume (PTV) and value doses of %2 and %98 showed significant improvement over 3D-CRT. For all studied organs at risk (OARs), the decrease in Dmax of HT was significant compared to 3-DCRT.

Helical tomotherapy enhances the target volume coverage and offers a good dose distribution. HT compared to 3D-CRT is a desirable method in treating head and neck cancer patients with the involvement of regional lymph nodes.

The increasing frequency of pediatric chest CT scans has raised concerns regarding the radiation-induced cancer risks. The aim of this study was to evaluate image quality, organ doses, effective dose, and radiation-induced cancer risk from pediatric chest CT scans.

This is a cross- sectional study that was conducted on 128 children under 15 years old (52 girls and 76 boys) who underwent non-contrast chest CT scans. Patients were classified into four age groups of ≤1, 1-5, 5-10, and 10-15 years old. ImpactDose software was used to calculate organ doses, and risk of exposure-induced death (REID) values were estimated according to the BEIR VII report. In addition, image quality criteria including image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were also investigated.

The mean values of REID in pediatric chest CT scans were 129.43 per 100,000 women and 49.59 per 100,000 men. REID values decreased with the increasing age of patients and were higher for girls than for boys. The SNR values for the descending aorta, subcutaneous fat, and back muscle were 3.14, 12.14, and 5.42, respectively. In addition, CNRaorto-fat and CNRmuscle-fat values were equal to 15.41 and 17.53, respectively.

Chest CT scan in pediatrics is related to an increased potential risk of cancer. Therefore, chest CT in children should only be requested if the diagnostic benefits outweigh the radiation-related risks.