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Abstract Background and Objective: One of the diabetes complications is the tissue damage caused by the imbalance of oxidants and antioxidants (oxidative stress). The aim of the present study was to evaluate the activity of two antioxidant enzymes -superoxide dismutase and catalase- in the serum of streptozotocin-induced diabetic rats. Material and Methods: This investigation was conducted on adult male rats assigned to diabetic and control groups. Diabetes was induced by a single intraperitoneal injection of streptozotocin. Seven weeks after diabetes induction, glucose concentration, superoxide dismutase and catalase activities of the serum were assessed. Results: Glucose concentration of streptozotocin-injected animals was significantly higher than that of control group (P<0.001). The level of Serum superoxide dismutase and catalase activities in diabetes group were significantly higher than those in control group (P<0.01). There was a positive significant correlation between glucose concentration and superoxide dismutase and catalase activities (P<0.001). Conclusion: The high activity of antioxidant enzymes in diabetic rats is probably due to compensation responses to oxidative stress produced by high concentration of free radicals. It seems that the higher glucose concentration, the greater compensatory responses. Keywords: Diabetes, Streptozotocin, Antioxidant, Superoxide Dismutase, Catalase

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Abstract Background and Objective: Escherichia coli is the most common cause of urinary tract infections in children and the leading cause of intra-abdominal infections (peritonitis and abscess) followed intestinal injuries. Urinary tract infection, including cystitis and pyelonephritis, is a common childhood infection. E. coli causes more than 90 percent of the community acquired and 50% of hospital acquired urinary tract infections therefore, the determination of E. coli antibiotic susceptibility is a paramount importance to clinical and epidemiological purposes. Material and Methods: In this cross-sectional study, 50 E. coli strains isolated from urine samples of children less than 7 years of age with urinary tract infections. They were compared for drug susceptibility testing by disc diffusion method with 50 strains of Escherichia coli isolated from stool samples of healthy children with the same age and sex pattern. Results: The actual amount of drug sensitivity of uropathogenic and intestinal Escherichia coli strains to amikacin was 94 and 100%, nitrofurantoin 90 and 88%, gentamicin 66 and 94%, cefixime 56 and 60%, nalidixic acid 38 and 44% and to cotrimoxazole 28 and 32%, respectively. Conclusion: the rate of resistance to gentamicin, Cefixime and nalidixic acid in urinary tract infection isolates were more than intestinal strains. The highest rate of drug resistance in urinary Escherichia coli isolates was associated with cotrimoxazole and the lowest one with amikacin. Keywords: Escherichia Coli, Intra-Abdominal Infection, Drug Resistance, Urinary Tract Infection, Children