مجله دانشکده پزشکی اصفهان
پیاپی 272 (هفته اول فروردین 1393)

Urinary tract infection is the most common nosocomial infection worldwide. Microorganisms causing urinary tract infections are resistant to most of the antibiotics. Pseudomonas aeruginosa (P. aeruginosa) is one of the major causes of nosocomial infections and its antibiotic resistance leads to medical implications associated with urinary tract infections. The aim of this study was to assess the prevalence of P. aeruginosa strains to identify their in-vitro susceptibility to antimicrobial agents and to determine genetic diversity of them.

Urine samples were obtained from catheterized patients in Shohada and Labafi Nejad hospitals, Tehran, Iran, and cultured by standard loop method. The cultures with more than 105 CFU/ml were assumed as positive. After identification of bacterial species by biochemical tests, susceptibility of each isolate was assessed by disk diffusion method according to Clinical and Laboratory Standards Institute (CLSI) guidelines. In order to analyze bacterial genotypic diversity, pulsed-field gel electrophoresis (PFGE) was performed.

116 out of 163 urine samples were positive for bacterial isolates. Pseudomonas species were placed in third step of the most frequent isolates. Antibiotic sensitivity was observed against most of antimicrobial agents. Some of strains were genetically similar.

This study revealed that isolated strains were sensitive to wide range of antibiotic agents. In addition, common type strains were responsible of causing inter- and intra-hospital urinary tract infections in catheterized patients.

Angiogenesis is a determinant factor in the treatment of cardiovascular diseases. The purpose of this study was determining the effect of testosterone on the average concentration of basic fibroblast growth factor (bFGF) and platelet-derived growth factor (PDGF) as angiogenic stimulating factors in the blood of male rats. In this experimental study, 24 male rats were divided into 4 groups. The first group went under sham surgery (making incisions without doing any special work on rats’ bodies) and 3 others went under the orchiectomy (OCX). The first and second groups received 0.1 mg/day sesame oil as placebo and the third and fourth groups received 1 and 5 mg/kg/day testosterone, respectively. After 21 days, the concentrations of bFGF and PDGF were measured in rats blood. The mean concentration of PDGF in rats in forth group was significantly more than those in third group (P < 0.05). In addition, the mean concentration of bFGF in third group was significantly less than the others (P < 0/05). Reduction of testosterone causes reduction of PDGF and it may be effective on decreasing the angiogenesis potentially. Different levels of testosterone had no effect on bFGF concentration.

Most of the studies support the statement that maternal periodontitis may be a risk factor for infants with preterm delivery and low-birth-weight (PLBW). The aim of the present research was to determine the effects of periodontal treatment on incidence of PLBW among women with mild to moderate periodontitis. 60 pregnant women received dental and periodontal examination [probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP)]. 30 of these pregnant women (the treatment group) received professional oral hygiene treatment including plaque and calculus removal and root planning at the beginning and end of 8th month of pregnancy. The control group just received the periodontal examination. The mean length of pregnancy and birth-weight were compared between the groups. Statistical analysis was determined using Kolmogorov-Smirnov, independent-sample t, Mann-Whitney U, Pearson and Spearman tests. The incidence of PLBW in treatment group was significantly lower than the control group (P = 0.006). No correlation was found between clinical parameters and the time of pregnancy or infant's weight. There was a weak positive correlation between the infant's weight and the improvement of clinical parameters. The results support the hypothesis that maternal periodontal disease is associated with infant prematurity and low birth weight. Therefore, the periodontal treatment can contribute to optimal date of delivery and achieving greater birth-weight.

The deficiency of factor XIII is a rare hemorrhagic disorder with the highest global incidence in Sistan and Baluchistan province in Iran. Bleeding of central nervous system (CNS) is a common but life-threatening clinical presentation of severe factor XIII deficiency. The aim of this study was to assess the role of Pro564Leu polymorphism in occurrence of intra- and extra-cranial hemorrhage in factor 13 deficiency. 32 patients with factor XIII deficient and history of CNS bleeding and 32 patients with factor XIII deficiency but without CNS bleeding were selected as case and control groups. Initially, the baseline for the Trp187Arg polymorphism was evaluated in both groups to confirm the disorder. Then, all the patients were assessed for Pro564Leu polymorphism. All the study patients were homozygote for factor XIII polymorphism. We also found that no patient in both groups was positive for Pro564Leu polymorphism. It seems that Pro564Leu polymorphism do not have any effect on occurrence of CNS bleeding in factor XIII deficiency.

In recent years, much more attentions have been focused on siRNA-based gene therapy. This approach is based on PTGS (Post-transcriptional gene silencing). Due to some defects in viral vectors, non-viral vectors have been used to deliver nucleic acids into target cells. Although, transfection efficiency in non-viral vectors is less than viral ones, but safety of non-viral vectors is much more. Characteristic features of siRNA, such as high compatibility, application in low doses and its versatility make it suitable in the gene therapy field. However, some challenges, such as stimulating immune system and Off-target silencing will be remain. In this review article, we express bottlenecks existing in siRNA delivery into target cells. According to the information, with further development of siRNA delivery in the future, it could be a promising approach in treatment for a variety of genetic diseases.