Tehran University Medical Journal

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In this study we review 82 infants under two months with bacterial meningitis admitted in Tehran University's hospitals during a 14 year period. Male to female ratio was 1.4 to 1. The patterns of predominance among bacterial pathogens changed during the period of study. During the first six years the most common pathogens were Salmonella-SP., but during the later years E.coli became the predominant pathogen, and also meningitis caused by GBS and Staph. epidermidis was observed. The case fatality rate was 37.8 percent. The antibiogram revealed that E.coli were hundred percent resistant to ampicillin and 50% resistant to gentamicin, 40% of all bacteria isolated were resistant to ampicillin and gentamicin. These findings provide guidelines for the selection of empiric antimicrobial agents in our country

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Many studies have shown the effectiveness of photorefractive keratectomy (PRK) in correction of vision in low and moderate Myopia. To evaluate the results of 193-nm exeimer laser photorefractive keratectomy for highly Myopic eyes, we reviewed refractive outcome of 43 eyes of 30 patients. Most eyes were treated with 1-step operation, using a 6 mm optical zone. 43 eyes were treated for Myopia, which were between -6.40 and -16.90 diopters. The mean pre-operative refraction was -9.50 D. All eyes were followed for at least 12 months. At 12tht month visit, 30.2% and 60.5% of eyes achieved correction within 1 and 2 D of attempted correction, respectively. At this time, 62.7% of eyes obtained 20/40 visual acuity or better uncorrected. At 1 year, 13% and 8% of eyes lost 3 and 4 lines of best-corrected visual acuity, respectively. Also 13% of eyes lost 2 lines. 12 months after PRK, 5 eyes developed corneal haze grade 2 and 2 eyes, grade 3 (0-5 scale). There was much undercorrection seen in this group compared with patients undergoing PRK for low and moderate Myopia. Photorefractive keratectomy for high Myopia, though effective, is not a safe and accurate procedure and is less predictable and stable than performing it for low and moderate Myopia.

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Background: Rheumatoid arthritis (RA) is an autoimmune disorder with unknown etiology. In recent years, a great number of studies have investigated the possible role of reactive oxygen species in the etiology and pathogenesis of Rheumatoid Arthritis. The aim of this study was to analyze the level of activities of catalase, glutathione peroxidas (GSH-Px), Super oxide dismotase (SOD) in patients with RA compared with the healthy subjects.
Methods: In a case-control study sixty rheumatoid arthritis patients 18-75 years old and 60 healthy sex and age-matched controls were selected, Catalase activity was measured by determining the constant rate (k) of hydrogen peroxide decomposition. GSH-Px activity of plasma was measured with spectrophotometer by Glutathione oxide generation due to GSH-Px. SOD activity is measured by degree of inhibition effect of SOD in generating super oxide radicals by xanthine and xanthine oxidase. C-reactive protein and rheumatoid factor values were determined by agglutination and latex tests.
Results: The plasma activity of catalase (p<0.001), GSH-Px (p<0.01), plasma level of hemoglobin and hematocrit (p<0.05) were significantly lower in patients with RA comparing with controls. The reduction in SOD activity was not significant (p>0.05). There was a negative significant relation between C reactive protein and Rheumatoid factor values with the erythrocyte activity of catalase and GSH-Px (p<0.01).
Conclusion: These results suggested that oxidative stress plays a very important role in the inflammation and pathogenesis of RA.

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Background: Recent studies have indicated the relation of vertebral endplate lesions (Modic changes) to low back pain (LBP). The aim of this study was to investigate the Modic changes in magnetic resonance imaging (MRI) of patients with low back pain, and its correlation with age, sex, type of changes, number of involved segments and location of changes. Additionally, association of degenerative disc changes and disc herniation was assessed.

Methods: In this retrospective study, MRI records of 229 patients with LBP referring to Medical Center of Hazrat-e-Rasoul Hospital, Tehran, Iran, from August to February 2014, were assessed and Modic changes and degenerative and herniated disc changes were recorded.

Results: Based on our observations, a significant association between Modic type and age (P= 0.003) existed in patients with LBP. The highest prevalence in Modic location were observed in anterior part of vertebral endplate (48.8%, P= 0.001). Although, observation of the Modic changes in superior vertebral endplate was higher than inferior parts, but this differences was not statistically significant. The highest prevalence in degenerative disc disease was disc dehydration which was observed in 18.1% of patients (P= 0.04). The relationship between the degenerative changes and Modic type was significant (P= 0.04), while the most prevalent change of disc contour was disc bulging which occurred in 23.7% of patients (P= 0.01). The highest frequency of abnormal disc contour were observed in Modic type 2 which was statistically significant (P= 0.01). Modic surface involvement above 25% was significantly associated with disc herniation (P= 0.04). There was no significant association between Modic height involvement above 25% and disc herniation.

Conclusion: Considering significant association between Modic changes and degenerative and herniated disc changes, reporting of Modic changes is necessary.

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Results: Forty patients were studied in four groups (three patient groups and one control group). 70 percent in Alzheimer group and 60 percent in vascular dementia group had abnormal pattern shift visual evoked potential. Only in Alzheimer group visual evoked potential P100 latency was significantly higher than control group and in other groups, there was no significant difference. Also there was no significant difference between groups in the study of flash visual evoked potential variables including P1, N2, P2 and N3.

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