مجله پزشکی کوثر
سال شانزدهم شماره 2 (پیاپی 60، تابستان 1390)

Considering that m elatonin is known as an effective ROS scavenger, it may be able to improve the in-vitro oocyte maturation and the fetal quality. This study was designed to determine the effect of melatonin on in-vitro oocyte maturation and fertilization and cleavage and blastocyst development rate in mice. This experimental study was carried out in the cellular-molecular center of Gilan Medical University in 2010. The cumulus-oocyte complex (COC) and germinal vesicle were obtained from mice. COCs were cultured for 18 hours in maturation medium (supplemented with different doses of melatonin (100, 10, 1 m M, 100, 10 m M) and control group and their maturation rate was assessed. Then two pre-nucleus embryos were cultured in T6 medium supplemented with different doses of melatonin and embryos’ developmental rate was recorded until blastocyst stage by inverted microscope. Data were analyzed using Chi-square test by SPSS 13 software. 1, 10 and 100 m M concentrations of melatonin had positive effect on in-vitro oocyte maturation and fertilization in mice compared to the control group (P<0.01). In addition, the cleavage and blastocyst development rate increased in presence of 10and 100 nM of melatonin (P<0.01). Melatonin as an effective ROS scavenger has positive influence on in-vitro oocytes maturation and embryos’ development promotion in mice.

Medullary thyroid carcinoma accounts for 5-10% of total types of thyroid cancers. An important role of mutations in the RET proto-oncogene in MTC has been well identified. The purpose of this study was to determine the prevalence of seven common germ-line mutations of the RET proto-oncogene in exon 10 in Iranian MTC patients.

This descriptive study was performed in year 2009-2010. The study population was 217 MTC patients and their first-degree relatives who were selected by simple sampling method. Genomic DNA content of peripheral blood was extracted according to standard salting out/Proteinase K method. Mutation detection in RET proto-oncogene in exon 10 was assessed through PCR-RFLP method.

In 217 individuals (Female: Male 1.4:1, mean age 33.4±15.8 years), 9 mutations were identified at codons 618 (7 mutations) and 620 (2 mutations) in RET proto-oncogene exon 10. The most common amino-acid change was Cys618Phe. In addition, no mutation was found in codon 611.

The mutations frequency of the RET proto-oncogene in exon 10 is 6% in the studied population. Accordingly, existence of the common mutations in the RET proto-oncogene in all MTC patients and their families is recommended particularly in other exons (11, 12, 13, 14, 15, 16) with a direct DNA sequencing method.

Oxidative damage of DNA is very important in mutagenesis, aging and cancer. The aim of the present study was to estimate the protective effect of aqueous saffron extract on DNA damage in sulfur mustard exposed macrophage cells as a genotoxic agent. Macrophage cells were obtained from mice peritoneum. The viability of cells was determined and then they were treated with KMnO4, SM and SM + saffron extract in culture media. The SM toxicity in macrophage cells was determined using MDA and GSH concentrations (nM/mg protein) and the extent of genotoxicity was investigated using alkaline comet assay and reported as the movement of DNA in electrophoretic field and %DNA remaining in the nucleus. The concentration of MDA and GSH in normal cells and KMnO4, SM and SM + saffron extract treated cells were respectively 1.9±0.18, 9.4±0.95, 9.3±1.2, 5.1±0.55 and 9.6±0.71, 2.4±0.32, 2.5±0.21, 4.81±0.39 nM/mg protein. The comet result showed that DNA movement in normal cell was 23.1±1.43 m m, but in KMnO4, SM and SM + saffron extract treated cells were respectively 39.75±4.92, 40.45±4.42 and 28.33±4.6 m m. Similarly, the percent of DNA in nucleus in normal, KMnO4, SM and SM+ saffron extract treated cells were respectively %99.3±3.6, 20.7±3.8, 22.61±4.3 and 65.5±4.8 that showed the significant protective effect of saffron extract on reduction of DNA damage in SM contaminated cells. The results demonstrate the anti-genotoxic effect of saffron aqueous extract against the oxidative damage of DNA caused by SM. However, the genotoxic activity of SM significantly reduced by treatment with aqueous saffron extracts. Therefore, it seems that the oral supplement of saffron aqueous extract can probably prevent the complications of these oxidative agents.

Diazinon is one of the most frequent organophosphate (Ops) insecticides that is widely used in agriculture. Some OPs are capable to produce free radicals and induce disturbance in body antioxidant systems. The aim of this study is to evaluate the effects of diazinon on antioxidant system in rat’s heart.

Male Wistar rats of One of Tehran medical universities were randomly divided into four 7-member groups. The control group received corn oil as diazinon solvent and three experimental groups received 30, 50 and 100 mg/kg of diazinon by intra-peritoneal injection. 24 hours after injection, the animals received ether anesthesia and heart tissue was removed. After heart tissue homogenization, superoxide dismutase (SOD), catalase (CAT), glutathione S- transferase (GST) and lactate dehydrogenase (LDH) activities, as well as glutathione (GSH) and malondialdehyde (MDA) levels were determined by biochemical methods data was analyzed by INSTAT software using one-way variance analysis and Tukey’s test.

At doses higher than 30 mg/kg of diazinon, enhanced activities of SOD, CAT and GST were observed, while GSH level significantly decreased compared to the control group. MDA level and LDH activity increased at 100 mg/kg dose of diazinon.

Diazinon induces the production of free radicals and oxidative stress in a dose- dependent manner. The enhanced activity of antioxidant enzymes and depleted GSH content is indicative of oxidative tissue injury and the increased MDA level is indicative peroxidation of membrane lipids of heart.

Recent studies suggest that sub-lethal ischemia protects the brain against subsequent ischemic injury. In this study, the nature of changes in the blood brain barrier permeability and brain edema following transient middle cerebral artery ischemia and 3-nitropropionic acid was evaluated. This clinical trial was carried out in Islamic Azad University of Zanjan in summer 2010. Rats were divided into 6 main experimental groups, each containing 28 animals. The first group (model of ischemic preconditioning) was subjected to 10 minutes of transient middle cerebral artery occlusion in the first day and was subjected to 60 minutes of middle cerebral artery occlusion in the second day. The second group (controls) did not receive any intervention except a 60-minute middle cerebral artery occlusion in the second day. The third group (sham) was only subjected to 10 minutes of transient middle cerebral artery occlusion in the first day. The fourth group (intact) was not subjected to any intervention. The fifth group (model of 3-nitropropionic acid preconditioning) received a single dose of 20mg/kg 3-nitropropionic acid in the first day and was subjected to 60 minutes of middle cerebral artery occlusion. The sixth group (control) received normal saline in the first day and a 60-minute middle cerebral artery occlusion in the second day. In the third day, the infarct volume, blood brain barrier permeability and brain edema was evaluated in the groups. Data was analyzed by SPSS 12 software by LSD method. Preconditioning with transient ischemia and 3-nitropropionic acid decreased neurologic deficit scores, infarct volume, brain barrier permeability and brain edema. Transient ischemia and 3-nitropropionic acid are associated with decrease in neurologic deficit scores, infarct volume, blood brain barrier’s permeability and brain edema; therefore, play active role in ischemic protection.

Animal studies have reported that Conjugated Linoleic Acid (CLA) has several health related benefitsincluding weight loss, loss of body fat mass, protein increase and reduction of fat accumulation. The object of the present study was to determine the effect of CLA supplementation on body weight, body composition, serum leptin and adiponectin in patients with type 2 diabetes mellitus.

The study was performed as a randomized double-blind clinical trial in year 2009 in the endocrine and metabolism research center of Shahid-Beheshti Medical University on 39 type 2 diabetic patientswho were receiving Metformin. Individuals were selected by refered sampling method and were randomly divided into two groups. One group took 3.0 g CLA/d and the control group took CLA placebo for 8 weeks. Blood samples were taken before and after the intervention in order to determination the levels of leptin and adiponectin. Weight, waist and hip circumference, body fat and lean body mass percent were also measured before and after the intervention. Data was analyzed by SPSS 13 software using paired t-test and ANOVA.

No significant difference was seen in serum leptin and adiponectin levels variation between groups. In addition, no significant difference was seen in body weight, BMI, waist circumference, waist to hip ratio, body fat and lean body mass percents.

CLA supplementation for two months may not improve body weight, body composition, serum leptin and adiponectin levels in type 2 diabetic patients. Further studies are needed to determine the long-term effects of CLA.

Pterygium is caused by a type of angiogenesis process and Bevacizumab (Avastin) acts against all kinds of VEGF and inhibits angiogenesis. According to the anti-angiogenic effect of Avastin and the considerable recurrence of Pterygium after surgery as the treatment choice, this study was conducted to evaluate the effect of this medication on recurrent Pterygium. This single arm clinical trial study was performed on 17 recurrent Pterygium patients who referred to the ophthalmology clinic of one of Tehran military hospitals during November 2008 to March 2009 and were selected by simple sampling method. Symptoms, refraction, astigmatism, angiogenesis and Pterygium size were measured at the beginning, at the first week and 1 and 3 months after injection of 1.25 mg Avastin in Pterygium bed. Data was analyzed by SPSS 11.5 software using Wilcoxon and Chi-square tests. Eye irritation (p=0.04) and Pterygium angiogenesis (p=0.001) significantly improved. No significant difference was observed in astigmatism, Pterygium size and the level of refraction (p>0.05). Avastin has significant effect on eye irritation and angiogenesis but has less effect on other symptoms; therefore, judgment about its efficacy on recurrent ptrygia needs further study

Various studies have been performed to evaluate the effect of physical exercise on factors related to cardiovascular diseases that mostly show the beneficial effects of regular physical exercise on these factors. However, little research has been performed on resistance exercises. The purpose of present study was to investigate the effect of mild and high intensity resistance training on some cardiovascular risk factors.

This clinical trial study was carried out in year 2009. The study population was non-athlete university students of Kurdistan. 30 young healthy me n were selected by random sampling method and divided randomly into three groups of experimental1, experimental2 and control group. The two experimental groups underwent resistance training for six consecutive weeks. ApoB, ApoA, LDL, HDL, ApoB/ApoA, LPL, TG, cholesterol, HDL /cholesterol, BMI, blood pressure and waist to hip ratio were assessed before and after the training period. ANOVA test with repeated measurement, paired t-test, one-way variance analysis and Bonferroni correction test were used for data analysis in SPSS 14 software.

After the training period, LDL, cholesterol, HDL /cholesterol and BMI significantly decreased in experimental groups. HDL only increased in the second experimental group. Other studied factors did not change significantly in any of groups.

Resistance training for six weeks in young healthy males can have beneficial effects on some cardiovascular risk factors. HDL response to resistance training is affected by the training intensity.

Toxoplasmosis is the disease caused by an intercellular protozoan called Toxoplasma gondii. Toxoplasma has global expansion and infects a wide range of warm blood animals. Presence of parasites inside cells affects cellular various activities and causes changes in cellular mechanisms. This study was carried out in order to evaluate the changes in testosterone level due to Toxoplasma gondii. This cohort study was performed on individuals who referred to one of Tehran military hospitals in year 2009. 180 people were selected by simple random sampling. 5 ml of blood was taken from individuals and 1 ml serum was separated and used in order to determine toxoplasmosis infection and testosterone concentration by ELISA method. Hirsutism, hair loss, weight and height were also evaluated and documented. The results were analyzed by SPSS 16 software using independent t-test and Pearson correlation. Of 180 serum samples (73 females and 107 males), 24femals (13/33%) and 39 males (21/66%) had anti Toxoplasma IgG antibody. The results showed significant correlation between Toxoplasma and testosterone increase in women (p=0.002), testosterone increase in men (p<0.0001), hair loss in women (p=0.002), hirsutism in women (p=0.001) and height increase in women and men, but there was no significant correlation between weight and Toxoplasma infection in women and men. There is a significant correlation between Toxoplasma infection and serum increase of testosterone, hirsutism, hair loss and height in patients. Results of this research can be beneficial in evaluation of disease symptoms and treatment protocol of toxoplasmosis patients for research centers and physicians.

Experimental evidence has shown the positive effect of physical exercise on skeletal mass. Previous studies show that biochemical markers can evaluate the dynamic changes in bone function and also determine the response rate of bone metabolism to physical exercise. The purpose of this study was to examine the effect of 6-Month aerobic exercise training on markers of bone metabolism in middle-aged women. This quasi-experimental study was performed on year 2009 on 19 healthy female middle-aged personnel of Ferdowsi University of Mashhad who were selected by convenience sampling method and were randomly divided into two experimental (11 people) and control (8 people) groups. The exercise protocol included aerobic (endurance) exercise training lasted for 6 months and 3 sessions per week and every session lasted for 60 minutes and with intensity of 55-65 percent of heart rate reserve. Independent t-test was applied to analyze the data by SPSS 16 software. The results showed no significant difference in concentrations of Parathyroid Hormone, Calcium and Alkaline Phosphatase in the experimental group in comparison with the control group. 6-month aerobic exercise training with the intensity of 55-65 percent of heart rate reserve does not induce significant change in the parathyroid hormone, calcium and bone-alkaline phosphatase in middle-aged women.