مجله دانشکده پزشکی
سال:1390 | دوره:69 | شماره:1 |تعداد مقالات:15

Background: Resistance to beta-lactam antibiotics in clinical isolates frequently results from the production of £]-lactamase enzymes. In recent years, the production of extended spectrum £]-lactamases (ESBLs) and AmpC £]-lactamase have greatly increased, especially in clinically isolated Escherichia coli. On the other hand, betalactamase genes have several subfamilies and designing universal primers could be valuable in their detection. The beta-lactamase-producing E. coli which is resistant to beta-lactam antibiotics may pose a great risk to the patients. The CTX-M-1 gene is responsible for beta lactamase resistance. The purpose of this study was to find the percentage of CTX-M-1 carrying E. coli strains.Methods: A total of 500 urine samples were collected from different hospitals in Tehran, Iran during September to February 2009. The samples were cultured on EMB agar and incubated at 37„a C for 24 hours. Some biochemical tests were carried out on the isolated samples. The presence of CTX-M-1 gene was determined by PCR on the isolates already identified phenotypically by disk diffusion agar and combined disks.Results: In general, 200 out of the initial 500 samples were identified as E. coli, among which 128 (79.5%) were ESBLs producing strains. PCR used for the detection of CTX-M- 1 gene, showed that 99 (77.34%) out of 128 isolates contained such gene.Conclusion: The results of this study showed a high percentage of £]-lactamase resistant E. coli strains. This is a serious matter and would pose a public hazard and every step should be taken to avoid such hazard.

Background: Propolis (bee glue) is a resinous substance obtained from bee hives living on various plant sources. The purpose of this study was to evaluate the effects of ethanol extract of propolis (EEP) on the experimentally induced Candidial keratitis in rabbits.Methods: The alcoholic extract of propolis was prepared by 80% ethyl alcohol. After suppressing the immune system of 24 male rabbits, experimental Candida albicans keratitis was induced in the animals under local anesthesia and sterile conditions. The animals were later divided into four groups including the control or glycerin group and a nystatin and two 500 and 1000ig/ml EEP groups. Treatment continued for 21 days and after sacrificing the animals by humane methods, histopathological samples of the rabbits’ eyes were prepared.Results: Keratitis was developed in the eyes of all rabbits a week after the yeast inoculation. In the control group in which animals received glycerin, keratitis persisted until day 21. Clinical signs of keratitis disappeared in the Nystatin and 1000ig/ml EEP groups after 14 and 21 days, respectively. The clinical signs of keratitis partially ameliorated in the animals receiving 500ig/ml EEP. Histopathological examination revealed no differences between groups receiving nystatin or 1000ig/ml EEP.Conclusion: It is concluded that, ethanol extract of propolis could completely treat Candida albicans keratitis in 1000ìg/ml concentrations. This extract can be used as a safe antifungal agent against Candida albicans and it is a good substitute for synthetic antifungal agents like nystatin.

Background: Atrial fibrillation is the most common but benign arrhythmia following cardiac surgery. Although this arrhythmia is often self-limited and vanishes in about 24 hours upon surgery; a number of arrhythmias might ensue among which some might be really life-threatening. A multitude of therapeutic modalities have been proposed for the prevention of this arrhythmia and one of them is posterior pericardiotomy. This method has not been fully accepted by the peers yet and more studies are needed to prove its efficacy and benefits to the patients.Methods: In this single-blind randomized clinical trial, done over a 2-year period from February 2009 to January 2011, the effects of posterior pericardiotomy were evaluated in 174 patients (87 the case and 87 the control groups) undergoing elective coronary artery bypass grafting (CABG). The case group underwent CABG with posterior pericardiotomy while the control group underwent CABG-only operation. The postoperative incidence of arrhythmia, especially atrial fibrillation, was assessed for a week using statistical methods.Results: The prevalence of postoperative atrial fibrillations were fewer in the group undergoing CABG with posterior pericardiotomy compared with the CABG-only group (P<0.004).Conclusion: Posterior pericardiotomy seems to reduce the incidence of atrial fibrillation following elective CABG; therefore, its application is suggested for elective CABGs.

Background: Reconstruction by free tissue transfer and microvascular anastomosis can provide a reliable repair for tissue defects in head and neck surgeries. During this study, we evaluated the clinical characteristics and outcomes of reconstructive surgery by the use of free flaps for defects resulting from head and neck cancers.Methods: This quasi-experimental study included 29 patients having been diagnosed with head and neck cancers and referred to the Plastic Surgery Clinic and Cancer Institute of Imam Khomeini Hospital Complex in Tehran, Iran, for the resection of cancerous tissue. After operation, the patients were followed-up for three months and the surgical outcomes were evaluated.Results: The mean age of participants was 50.8 ± 15.1 yrs. Two patients (6.9%) had total and three (10.3%) had partial flap loss. The rate of total and partial flap loss in this study was less than 10%. There were no differences between groups with total and partial flap loss regarding mean age, mean operation time, and mean perioperative ischemia time. Prothrombin time (PT) and international normalized ratio (INR) were significantly different in patients with total flap loss compared with patients with successful reconstruction. The INR for the group with total loss was 2.2 and 1.2 ± 0.3 for other patients (P=0.0006). The mean ACT was 46 seconds in patients with total flap loss and 82 ± 18.9 seconds for other patients (P=0.08).Conclusion: Considering its high success rate, free tissue transfer can be considered as a method for single-stage reconstruction in almost all major head and neck defects.

Background: Sputum induction has been recently introduced as an effective and inexpensive method for obtaining high quality sputum samples in patients without spontaneous sputum. As all Iranian physicians might not be familiar with this method yet, the results of this study could be of help in this regard.Methods: During June 2010 to January 2011, all pulmonary tuberculosis (PTB) suspected patients, with clinical and/or radiological evidence in favor of PTB who had been referred to the Pulmonary Diseases department of Imam Khomeini Medical Center were enrolled in the study, if they were without spontaneous sputum. Sputum induction was performed using ultrasound nebulized hypertonic 3% sterile saline for 20 minutes. The laboratory was requested to report if the samples were of the intended quality (Polymorphonuclear Cells/Squamus Epithelial Cells³2). The patients’ demographic data, HIV serology and chest radiological findings in favor of PTB were recorded and analyzed.Results: In 50 patients with suspected PTB [23 men (mean age (±SD), 51.21±20.24) and 27 women (mean age (±SD) 55.40±18.00)], cough was the most common complaint. The most prevalent radiological findings were infiltration and consolidation. PPD was positive in 21 (42%) patients. Sputum induction led to obtaining proper sputum samples in 90% of the patients. Positive sputum smear and culture were seen in 13 (26%) cases.Conclusion: Sputum induction is a cost-effective and minimally invasive method which is associated with satisfactory results for obtaining high quality sputum samples in patients without spontaneous sputum.

Background: Many studies have shown that periodontal pathogens are emerging as a risk factor for preterm delivery and low birth weight, but there are few studies about the relationship between other oral bacteria and pregnancy outcomes. The aim of the present study was to determine the relationship between salivary bacteria and pregnancy outcomes.Methods: This cohort study was performed on 300 pregnant women who were recruited from the prenatal clinic of Zeynab Hospital in Tehran during 2009-2010. The patients’ demographic and pregnancy data were recorded. Using samplers, saliva samples were collected about one hour after breakfast. Microbial evaluation was performed by counting the bacteria based on their shape and the Gram reaction. The studied bacteria were composed of gram-positive and negative cocci, gram-positive and negative bacilli, spirilla, spirochetes, yeasts, fusiform bacteria and actinomycetes.Results: The data on the bacteriological profile and pregnancy outcome of 243 out of the 300 eligible participants of the study were completed. Five cases (2%) had intra uterine fetal death (IUFD) while 238 (98%) delivered live infants. There was a significant statistical relationship between the mean of gram-negative cocci and IUFD (P=0.04). 10 cases (4.1%) of 243, experienced adverse delivery outcomes and 233 cases (95%) had normal delivery. The adverse pregnancy outcomes had a significant relationship with the presence of spirochetes in saliva (P<0.05) but this relationship was not true for the other bacteria.Conclusion: Some oral bacteria may pose a risk for premature deliveries and low birth weights.

Background: Infections caused by opportunistic yeasts such as Candida species, Trichosporon, Rhodotorula and Saccharomyces have increased in immunocompromised patients and their identification is crucial as intrinsic and acquired resistance of some yeast species to antifungal agents are on the rise. The aim of this study was to identify the organisms to the species level in order to suggest accurate and effective antifungal therapies.Methods: In this study that carried out in Tehran, Iran in 2009, 200 patients with yeast infection were medically examined and clinical specimens were prepared for direct examination and culture on Sabouraud dextrose agar. Subsequently, the isolated yeast colonies were identified using various tests including culture on Corn Meal agar with Tween 80, CHROMagar Candida and casein agar. For the definite identification of organisms some biochemical tests were done based on carbohydrate assimilation by RapID Yeast Plus System kit, and, finally, a molecular method, PCR-RFLP, using Hpa II enzyme, was performed for the remaining unknown yeast species.Results: A total of 211 yeast isolates were identified in 200 patients with yeast infections. The most frequent isolated yeasts were Candida albicans, 124 (58.77%), followed by Candida parapsilosis, 36 (17.06%), Candida tropicalis, 17 (8.06%), Candida glabrata, 13 (6.16%), Candida krusei, 8 (3.79%), Candida guilliermondii, 2 (0.96%), Trichosporon, 3 (1.14%), Rhodotorula, 1 (0.47%), Saccaromyces cerevisiae, 1 (0.47%) and other yeast species, 6 (2.84%).Conclusion: Nail candidiasis was the most prevalent type of yeast infection in the patients and Candida albicans was the most frequent isolated species from all clinical specimens.

Background: Soft tissue chondroma is a rare slow-growing benign cartilage forming tumor. Tumors of this kind arise from the relative mesenchymal tissue and have tendency to occur in the fingers and toes. Due to its rarity, this tumor is likely to go undiagnosed. Histopathological examination usually reveals the correct diagnosis.Case presentation: Hereby, we report a case of soft tissue chondroma in a 27 year-old woman presented with a slow-growing mass in the volar aspect of her right hand. The tumor had developed over a 7-month period. The skeletal system was unremarkable on X-ray evaluation. The lesion was excised and the histopathological findings revealed a well-delineated cartilaginous neoplasm with lobular pattern. The tumor was composed of mature chondrocytes without atypia and the findings were compatible with chondroma.Conclusion: There are various hypotheses about the etiology of soft tissue chondromas and their microscopic findings are variable. They have a good prognosis. Recurrence is rare and malignant transformation has not been reported yet.