مجله دانشگاه علوم پزشکی شهرکرد
سال سیزدهم شماره 1 (پیاپی 49، فروردین و اریبهشت 1390)

Methadone is a synthetic opioid, used in the treatment of opioid dependence and chronic pain. The aim of this study was to investigate histopathological effects of methadone on central nervous system of mice newborns in suckling period. In this study, twenty eight mature pregnant mice were randomly divided into four groups of seven each. Three groups were intraperitonealy injected methadone (3, 6, 9 mg/kg per day respectively) from first lactational day until weaning. Control group was injected distilled water saline. At the 27th day, respectively offspring were weighed and anesthetized with choloroform and then their brains removed from their skulls and immersed in the fixative formalin buffer 10% for 24h and samples were stained with Hematoxylin and Eosin stain for the histopathology study. The data were analysed using one way ANOVA and Sheffe tests. Methadone caused a significant reduction in both weight and Crown Rumpa-Length and also an increase in the brain to body mass ratio in experimental groups compared to the control group (P<0.001). In addition, offsprings who received methadone during lactational period showed changes in the brain neuronal degeneration along with apoptotic cells in the regions of DG and CA3 of the hippocampus. Methadone consumption during lactational period can cause reduction in growth indices and structural disorders in the offspring brains

Purslane (Khurfeh) is one of the richest sources of omega3 fatty acids in plants and it has many antioxidants and minerals in its different parts. High density lipoprotein (HDL) has antioxidant effects because of Paraoxanase-1 (PON1) enzyme which attaches to HDL particles and circulates with it in blood. PON1 is responsible for hydrolysis of oxidized phospholipids. The aims of this study were investigating the Purslane effects on Paraoxanase-1 activity and lipoproteins levels, especially oxidized low density lipoprotein (OxLDL) and to compare these effects with Lovastatin. Fasting venous blood samples were obtained from patients who were referred to an internal clinic with LDL-C more than 100 mg/dl. Five ml of blood was taken before and 45 days after taking Purslane or Lovastatin. Subsequently the levels of all variables in the samples were measured using standard methods. Results were analyzed using paired t-test and t-test. There was a significant decrease in serum level of cholesterol, LDL-C and OxLDL in two groups after receiving Purslane or Lovastatin (P<0.05). ApoB was decreased only after taking Lovastatin. PON1 arylesterase activity was increased only in Purslane group following increasing of Apo A1 and HDL-C. Body mass index (BMI) and triglyceride was decreased in Purslane group (P<0.05). Purslane reduces some cardiovascular risk factors through decreasing OxLDL, LDL-C, total cholesterol and triglyceride levels and increasing activity of paraoxanase-1 enzyme and HDL-C concentration. In addition, Purslane can increase ApoA1 better than Lovastatin.

Our environment is exposed to electromagnetic fields by development and industrialization of life. The aim of this investigation was to evaluate the effects of extremely low frequency electromagnetic fields (5 and 25 Hz) during fetal life on adulthood learning in male rat. In this study forty eight Sprague ِDawley pregnant rats (150±20g) were divided into six groups of eight: control, sham, and 5 or 25Hz and 50 or 500µT. Duration of exposure was 4 hours per day (continuously from 8 to 12 A. M.) from first day to 15th day of gestation. We evaluated learning, body weight, brain weight, brain volume, brain weight to body weight ratio and brain density of 60 days-old male offsprings. The learning task was performed by shuttle box in the form of one-way active avoidance conditioning. The number of conditioning responses and latency periods was recorded. Data was statistically analyzed by Kruskal-wallis test. Fetal life exposure to ELF EMF (25Hz/50µT) improved learning, decreased body weight and increased brain weight to body weight ratio in male rat (P<0. 05). Fetal life exposure to 25 Hz/500 µT, 5 Hz/500 µT and 5 Hz/50 µT increased body weight. Fetal life exposure to ELF EMF (25Hz/50µT) could improve learning in male rats.

Enhancement of blood factor 7 or fibrinogen is considered as cardiovascular risk factors. This study was, therefore, aimed to evaluate the effects of Sesamum indicum seed and oil on fibrinogen and factor 7 in hypercholesterolemic rabbits. In an experimental study, 32 NewZealand rabbits were randomly designated into 4 groups of 8 and were fed for 60 days as following: normal diet, hypercholestrol (1%) diet, hypercholestrol (1%) diet+10% sesame seed, hypercholestrol (1%) diet+5% sesame oil. At the beginning and 60 days after the start of the study, the blood fibrinogen and factor 7 were measured and compared in different groups. There was no difference for fibrinogen and factor 7 in different groups at the start of the study, however, the blood fibrinogen and factor 7 were increased in hypercholesterolemic group compared to normal diet group (P<0.05). The amounts of blood fibrinogen and factor 7 were decreased in hypercholesterol+sesame seed and in hypercholesterol+sesame oil groups compared to hypercholesterol diet group (P<0.05). Sesame seed and oil may have beneficial effects on cardiac function by decreasing blood fibrinogen and factor 7 as cardiovascular risk factors.

Due to significant role of air pollutants on lung diseases this study aimed to examine the effects of concentration of air pollutants (CO،SO2،NO2) on Spirometric lung function. The sample cities, Arak (as an industrial contaminated city) and Khomain, (as a non-contaminated non-industrial city), were divided into Ira 10 and 5 regions, respectively. A sample of air pollutants (CO،SO2،NO2) was measured randomly by PSI (Pollution Standard Index) machine throughout the year from spring to winter. Random samples consisted of 522 non-smokers from Khomain and 547 from Arak were selected. Pulmonary function tests were completed on all participants. The mean concentration of air pollutants and distribution index of lung capacity were subjected to regression analysis. Analysis of the results showed that PSI in Arak was 101. 83±4. 54 and in Khomain was 89. 17±18. 58 (P<0. 05). Measured values FVC and PEF in Arak were significant lower than Khomain (P<0. 05). The mean values for the concentration of CO, SO2 and NO2 in Arak were higher than Khomain, although the differences were significant only for CO and SO2 (P<0. 001). The three pollutants (NO2, SO2 and CO) showed a significant correlation between mean VC (P<0. 001) FVC, (P<0. 05) with concentrations of SO2 and PEF with NO2 (P<0. 001). In Arak, the correlation between the predicted FVC and concentration of CO was negative and significant. The mean value of concentration of SO2, CO and NO2 in Arak were higher than Khomain. In Arak, a significant negative correlation was also observed between FVC and the concentration of CO. These pollutants and their resources should be annually measured and monitored.

MRI (Magnetic Resonance Imaging) is one of the best diagnostic techniques in medicine. During an MRI examination, three types of field are employed to produce images. Various experimental studies have been performed about effects of each single type of field, but only few studies are available on their combination to generate MRI. The main objective of this research was to study the effects of MRI on the sex hormones and other fertility parameters in adult male rats.

In this experimental study, 40 adult male Wistar rats (220±10 g) were randomly divided into two protocols. Each protocol contained two groups of exposed (10 rats) and control (10 rats) rats. Exposed groups were placed in MRI for 25 minutes. After MRI, the animals of the first protocol were placed in the holder and scrotal skin temperatures were measured by the thermometer. These animals were anaesthetized and serum samples were obtained and stored. Then, the testes were cut and weighed. After 96 hours, these experiments were repeated for the animals of second protocol.

Our results for the first protocol (after MRI) indicated that there were no significant effects on the testes weight, scrotal skin temperatures and serum levels of LH in the exposed rats. However, the serum level of testosterone was significantly reduced (P<0.001) and serum level of FSH was increased (P<0.001). Regarding the second protocol (96 hours after MRI), significant increase was observed for FSH, just in the exposed rats, which was similar to the first protocol (P=0.04).

Our results suggest that MRI causes dysfunction in the secretion of some sex hormones in the adult male rats.

Some investigators believe that the amount of REM sleep is increased after learning of some tasks, and learning processing and memory consolidation occur during some of these periods. These specific periods are called Paradoxical Sleep Windows (PSW). The neurochemical nature of PSW and its active neurotransmitter are unknown. NMRI rats were trained in a two-way shuttle avoidance task (100 trials per one session) and memory retention was tested one week later. Those animals that reached to 70% learning criterion were divided into 8 groups. In drug section, the animals of each group were administrated saline, caffeine (25mg/kg), adenosine (7mg/kg), adenosine (50mg/kg), physostigmine (0.1mg/kg) or Scopolamine (5mg/kg i.p.), after learning. In drug-deprivation section, the first group was deprived from REM sleep for 1-4hr after learning with platform technique. Animals in second group were administrated caffeine (25mg/kg) in addition to REM sleep deprivation for 1-4 hr after learning. Injection of caffeine caused a significant increase in memory (P<0.05). Deprived animals showed a significant memory deficit (P<0.05) and caffeine attenuated memory impairment which was induced by paradoxical sleep deprivation. Other drugs had no significant effect on memory. Caffeine can enhance memory and attenuate paradoxical sleep deprivation-induced memory impairment. Effects of caffeine on memory involve systems other than cholinergic and adenosine systems. Memory processing which occurs in PSW can not be attributed to one neurotransmitter system.

Thalassemia is the most common single gene disorder which is not completely cured. It is needed to find a reliable and cost-effective prevention method for screening the disease. For the next step, it is needed to give proper education, genetic consulting and prenatal diagnosis for the patients and finally selective termination of affected fetuses. The aim of this study was to evaluate effectiveness of the Naked Eye Single Tube Red Cell Osmotic Fragility Test (NESTROFT) as a screening test for beta-thalassemia trait. In this descriptive –analytical study, NESTROFT was applied to a total of 158 subjects who were divided into three groups. Group I was comprised of 51 individuals belonging to parents whom at least one of the children was suffering from ß-thalassemia major, group II was consisted of 51 normal individuals and finally group III was comprised of 56 individuals with iron deficiency. The findings of this study showed that sensitivity of the test was as high as 100 percent and specificity was 86.9 percent. The predictive value of the positive test was 78.5 percent and the negative test was as high as 100 percent. False positive results were obtained in 14 cases with iron deficiency. NESTROFT emerged as a highly sensitive, inexpensive and easy to perform test for exclusion of beta-thalassemia trait. It is therefore a suitable test for large-scale use in a developing country such as Iran, which has got limited financial and technical resources.

Due to the conditions provided by the modern life, the human being is exposed to electromagnetic field (EMF). Appliance such as microwave oven, mobile phone, computer and power producing systems which have an extensive role in human life are the source of EMF. Epidemiological and experimental studies have shown the adverse effect of EMF on biological systems. Previous works, using light microscopes have shown that EMF could produce morphological changes in cardiovascular system. However, there are few studies regarding ultrastructural effect of EMF on living tissues. The aim of the present study was to investigate ultrastructural changes of cardiovascular system in EMF–exposed rats. Wistar rats were exposed to 3mili tesla EMF for 4 months, 4 hours/ day. After the experimental period, rats in control and experimental groups were sacrificed and tissue samples were prepared from the heart for electronmicroscopic studies. The studies on the endocardium revealed that there was nuclear condensation and destruction of subendocardial layer in experimental group. In myocardium, in addition to nuclear condensation the mitochondria were also vague. There was a remarkable gap between the endothelial cells and basement membrane in the vessels of heart tissue. Epicard layer in EMF-exposed group was thinner than the control group. The obtained changes in the present study indicate the harmful effect of EMF on cardiovascular system after long-term exposure. It demands a protective policy for human being from probable effects of EMF.

Encountering clinical environments as an inseparable part of studying medicine could bring about tension and anxiety for medical students. Early clinical exposure has been suggested to decrease these stresses and to motivate students for a better attitude and awareness. This study was performed to determine the effect of a short-term period of exposing to clinical environment on medical students’ attitude toward medical education and their educational function.

In an interventional study performed as pre-test/post-test, 43 first year medical students were encountered clinical environments in rounds, operating rooms and emergency ward. Students’ attitude was assessed by a questionnaire using Likret scale. We compared student's function in specific lessons and result of comprehensive basic examination with previous entrance students as an external control group.

Significant differences were found in the student’s attitude before and after the course (P<0.01). Results showed a significant increase in the student’s attitude toward importance of the patient's history and physical exam versus para-clinical exams. In addition, their attitude about therapeutic stuff duties in all levels. The rules between physician and patient, patients rights in hospital, diagnosis and therapeutic management, different steps of medical education and merging basic and clinical sciences, simple physical exam and assistance management were increased significantly after the course. No significant difference was observed in the student's educational function in any items.

Based on the results of this study, we found a positive effect of early clinical exposure on attitude of first year medical students. Therefore, we suggest that early clinical exposure be added to educational curriculum for medical students.

Preeclampsia is one of the main complications during pregnancy and one of the three major contributors to maternal mortality. The aim of this study was to evaluate the preeclampsia correlation with season and seme of its risk factors in attending women to maternity hospital of Ghods in Zahedan city, Iran. The files of pregnant women with preeclampsia who were admitted in maternity hospital of Ghods in Zahedan city during years 2004–2007 were used for the study. The patients in case group were 2488 ones who had the requirements of the study (age: 15- 45 year, gravid: 1-3), and then other 2488 pregnant women without preeclampsia were selected as control group. The approach of sampling was through simple sampling. The way of getting data achieved through filling questionnaires from the patients files. The results of this study showed that there is a significant relation between preeclampsia and seasons. At the start of spring it gradually began to increase and reached to its peak in Autumn and then it suddenly decreased in the winter The most important factors of the prevalence of preeclampsia were hypertension, diabetes and previous preeclampsia, respectively. We found a relationship between the number of preeclampsia incidence and season. Therefore, precautions should be considered in those seasons in which the preeclampsia is increased. Attention to this prenatal care centers may help to decrease in this regard the serious side effects that endanger the health of mother and fetus.