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Introduction: The increasing use of the electromagnetic field producer sets in daily living causes concerns about these waves on human health. The effects of extremely low frequency electromagnetic field (50 Hz) on induction of chromosomal damages on bone marrow erythrocytes of male Balb/C mouse has been investigated in this research. Materials and Methods: This is an experimental study in which the laboratory system of producing electromagnetic with low frequency (50 Hz) was used. Five week old male Balb/C mice were divided into three controls, sham-exposed and experimental groups. The experimental mice exposed were exposed to electromagnetic field (50 gauss) for 4 days (12 hours/day). After treatment, the chromosomal damages were assessed using micronucleus test in polychromatic erythrocytes and resultant quantity data were analyzed using t and Mann-Whitney test. Results: Results showed that frequency of micronucleated polychromatic erythrocytes of experimental group (14/35±1/589) was more than Sham-exposed (8/958±1/049) and control group (7/65±0/768) significantly (p<0/05). Conclusion: Extremely low frequency electromagnetic field (50 Hz) causes chromosomal damages induction in polychromatic erythrocytes of bone marrow male Balb/C mouse.

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Background: Otoacoustic emissions (OAEs) are faint sounds generated within the inner ear that can be regarded as a sensitive tool for reflecting inner ear status. There are various factors that may influence OAE recording. One such factor that has not been extensively examined to date is body position. The aim of this study was to examine the effect of body position on the OAE responses of adults with normal hearing. Materials and Methods: In an analytic cross-sectional study, 26 normal hearing adults (18-25 years old) were evaluated. Transient OAEs (TEOAEs) were recorded in five different positions: supine, sitting, side-lying, 30°-Up, and 30°-down to evaluate their inner ear function. Data were analyzed using SPSS software 17. Results: Mean TEOAE amplitude values were significantly higher in the side-lying position compared to other positions (P=0.01). The most significant TEOAE amplitude differences were observed at the high frequencies (3000 Hz and 4000 Hz) in side-lying position orientation compared to low and medium frequencies. Conclusion: The results from the present study revealed that body position has a remarkable effect on inner ear function, and this effect is more obvious at high frequencies.

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Background: Due to the changing lifestyle in terms of nutrition and physical activity, obesity has become one of the major challenges to human health. The study of metabolic factors involved in this phenomenon plays an important role in preventing and treating the obesity. The aim of this study was to investigate the relationship between testosterone level and serum lipoproteins such as LDL and HDL with Body Mass Index (BMI), in different age groups of men in Golestan population.

Materials and Methods: In this case-control study, 183 men were randomly selected during 2012. Anthropometric measures (weight and height) were obtained according to standard methods, and BMI was calculated for each one. Data was analyzed using SPSS version 16. Pearson bivariate correlation test between groups and one-way Anova test was performed and p<0.05 being considered as significant.

Results: Data analysis showed a significant inverse correlation between BMI and serum testosterone level (p=0.005). In the study population, higher BMI was associated with increased LDL level (p=0.049) and also increasing age (p=0.011). In addition, an inverse relationship was observed between BMI and HDL levels that were not statistically significant (p=0.068).

Conclusion: The results of this study indicate that weight gain is associated with increased LDL and low testosterone serum level, and this relation is more meaningful in old men.