In this study, we present a simple and eco-friendly method for extracellular biosynthesis of gold nanoparticles by Streptomyces sp. ERI-3 cell-free supernatant. The research was also aimed to evaluate the effects of different reaction parameters including incubation temperature, reaction time, HAuCl 4 concentration and pH on gold nanoparticles production. The UV-Vis spectroscopy was used to monitor the formation of gold nanoparticles. The synthesized gold nanoparticles were characterized with XRD, TEM, and SEM. The average particle size ranged from 10 to 30 nm with spherical shape at optimum conditions.

Background: Obesity is an energy imbalance disorder that happens due to deficiency of energy intake and consumption. Leptin is an important hormone that regulates energy expenditure. Leptin through its receptors located in the hypothalamus regulates appetite and energy consumption. Objectives: In this study we tried to determine the association of leptin receptor (LEPR) gene polymorphisms (rs1137101), Lys223Arg and Gln109Arg (rs1137100), with overweight and obesity. Methods: We examined the two polymorphisms in 240 subjects consisting of obese, overweight, low-weight, and normal weight (as control) subjects among students of Zanjan Islamic Azad University. For Genotyping, we used PCR-RFLP. Statistical analysis was performed using t-test and chi-square test to show any significant difference between the groups. Results: There was no significant difference in allelic and genotypic frequency of Gln109Arg polymorphism (by A > G substitution) between our study groups. In Lys223Arg polymorphism by A > G substitution, the frequency of AG genotype was higher in the normal group, and the frequency of AA genotype was higher in the obese and overweight groups; but, there was no significant difference in GG genotype and allelic frequency (P < 0.05). Conclusions: In our population, Lys223Arg polymorphism of LEPR gene was associated with obesity; Gln 223 of leptin receptor gene was located in the extra cellular part of receptor and substitution of Glu by Arg in this position might affect leptin signaling. Lys/Arg heterozygote might have protective effects.

Background: Restenosis after coronary angioplasty can have serious complications such as coronary artery bypass graft, myocardial infarction, and death. Objectives: The present study aimed at investigating the factors affecting the recurrence of coronary artery stenosis in patients undergoing angioplasty using the recurrent event data analysis. Methods: A cohort study was performed on patients undergoing coronary angioplasty from March 23, 2009, to January 21, 2011. All patients were followed up from angioplasty to January 21, 2015. First, each of the independent variables was entered into the univariate Cox model with a frailty component. Then, variables with p-values of less than 0.2 were entered into the multivariate analysis. The statistical analysis was done using R software, version 3.6, at the significance level of 0.05. Results: The present study was conducted on 1,000 patients who underwent coronary angioplasty. We found that 441 patients experienced restenosis at least once in the study period. The mean survival time to the first event of restenosis was 44.08 ± 1.06 months. Patients with a history of diabetes, unstable angina, and myocardial infarction had a significantly higher hazard of restenosis compared to other patients (P < 0.05). Conclusions: The results of the recurrent event survival analysis confirmed the significant role of risk factors such as a history of diabetes, unstable angina, and myocardial infarction. Therefore, training to enhance the patients’ awareness and attitude seems necessary to prevent them from exposing whit known risk factors. The periodic follow-up of patients with risk factors and more ongoing care are also necessary.

Introduction: Restenosis after stenting constitutes is one of the major concerns among cardiologists' experts. This may lead to repetition of angioplasty, coronary artery bypass graft surgery, myocardial infarction, and even death. The present study, by using Cox's regression model aims at determine the demographic and clinical factors affecting time to incidence of cardiovascular restenosis in patients' undergone angioplasty in Zanjan, Iran. Methods: In this descriptive longitudinal study, 421 patients who visited Zanjan's Ayatollah Mousavi hospital for drug eluting stent implantation between April 2009 and June 2011 are scrutinized with respect to the time of the incidence of restenosis. Next, demographic variables and patients' clinical records are entered into "Data Gathering Form of Patients' Undergone Angioplasty". Data is analyzed using Cox's regression and SPSS 21. Results: The mean time of restenosis incidence is 736 days and the rate of restenosis incidence is 30.4%. Hazard ratio of restenosis in unemployed patients is 1.39 times, in drug addicted patients 1.75 times, in patients with a history of hyperlipidemia 1.57 times, and in patients with chronic kidney disease is 1.58 times more than other patients (P < 0.05). Conclusions: This study indicated that the most important factors leading to the incidence of restenosis are unemployment, drug addiction and abuse, suffering from hyperlipidemia, and chronic kidney diseases. Accordingly, it is highly recommended to prevent patients from above-mentioned risk factors and plan a periodic and continuous follow-up for patients with any of these factors.