مجله دانشکده پزشکی دانشگاه علوم پزشکی تهران
سال هفتادم شماره 9 (پیاپی 141، آذر 1391)

Staphylococcus aureus is the most common pathogen responsible for skin and soft tissue infections worldwide. Methicillin-resistant S. aureus is a major cause of both nosocomial and community acquired infections. The emergence of antimicrobial-resistant S. aureus is of global concern. Fluoroquinolone antimicrobials including ciprofloxacin، levofloxacin، and moxifloxacin are used to treat skin and soft tissue infections due to S. aureus. Emergence of ciprofloxacin resistance has increased in community acquired methicillin-resistant S. aureus strains. The aim of this study was to evaluate the minimum inhibitory concentration of ciprofloxacin and hexahydroquino-line derivatives against methicillin- and ciprofloxacin-resistant S. aureus. Identification of S. aureus was performed by routine microbiological tests in the Department of Pathobiology in Winter 2012. The susceptibility of S. aureus strains to both methicillin and ciprofloxacin was examined by the Kirby-Bauer disk-diffusion method. The minimum inhibitory concentration of ciprofloxacin، hexahydroquinoline derivatives and their combination were separately determined by broth microdilution method against methicillin- and ciprofloxacin-resistant S. aureus. The minimum inhibitory concentration of ciprofloxacin decreased in the presence of hexahydroquinolinein derivatives in comparison with ciprofloxacin alone. This study showed that hexahydroquinoline derivatives enhance the antibacterial effect of ciprofloxacin against methicillin- and ciprofloxacin-resistant S. aureus. Therefore، these derivatives could be used as inhibitors of antibiotic resistance in combination therapies. This enhancement may be related to the inhibitory effect of hexahydroquinoline derivatives on the expression of antibiotic efflux pump in the bacteria. However، the structural features of a fluoroquinolone that determine whether it is affected by efflux transporters are not fully defined.

Diabetes mellitus affects numerous intracellular metabolic processes، which are reflected by changes in the concentration of some plasma constituents. Particularly، the disease may indirectly undermine some functions of the nervous system including learning and memory through altering oxidative stress status. On the other hand، probiotics can enhance the antioxidant capacity. This study was designed to evaluate the effects of probiotics on spatial memory، maze learning and indices of oxidative stress in diabetic rats. In this experimental study، 40 male Wistar rats were randomly allocated to 4 groups (n=10 for each): Control (CO)، Control probiotic (CP)، Control diabetic (DC)، and Diabetic probiotic (DP). The probiotic supplement، including Lactobacillus acidophilus، Lactobacillus fermentum، Bifidobacterium lactis (334 mg of each with a CFU of ~1010)، was administered through drinking water every 12 hours for 8 weeks. Using morris water maze (MWM)، spatial learning and memory were evaluated. Serum insulin and oxidative stress indices، including superoxide dismutase (SOD) and 8-hydroxy-2''-deoxyguanosine (8-OHdG)، were measured by standard laboratory kits. Oral administration of probiotics improved impairment of spatial learning (P=0. 008) and consolidated memory (P=0. 01) in the rats. Moreover، probiotic treatment increased serum insulin (P<0. 0001) and serum superoxide dismutase activity (P=0. 007) while it decreased their blood glucose (P=0. 006) and 8-OHdG (P<0. 0001). Probiotic supplementation reversed the serum concentrations of insulin and glucose along with an increase in antioxidant capacity in diabetic rats. It also improved spatial learning and memory in the animals. Relevancy of the metabolic changes and behavioral functions need to be further studied.

The high number of breast cancer patients who receive radiation therapy after surgery has caused many to think about a shorter period of radiotherapy، which can significantly reduce the radiotherapy machine time، labor hours، and fewer patient visits. This study was designed to evaluate the acute skin effects and cosmetic outcomes of short course radiotherapy in early-stage breast cancer in comparison with the conventional treatment method. Fifty-two patients with operable breast cancer (pT1-3pN0M0) who underwent breast conservation surgery in Tehran Cancer Institute during January 2011 to January 2012، were randomly assigned to undergo radiotherapy by either receiving conventional treatment (dose: 50 Gy in 25 fractions) with subsequent electron boost or a short-course hypofractionated radiotherapy (dose: 42. 5 Gy in 16 fractions) and a subsequent electron boost. There were no skin changes during the first or the second week of treatment in the two groups. Cutaneous complications began after the third week as grade 1 skin toxicity after termination of the short-course radiotherapy but there were no difference in complication rate after four weeks of treatment. Six months and one year after treatment، there were no differences in terms of skin complications or cosmetic outcomes between the two groups. Although the use of a whole-breast irradiation with a hypofractionated schedule was associated with desirable outcomes، in term of skin toxicity and cosmetics، but longer follow-up periods with larger sample sizes are needed to confirm these results.

Control of intracranial pressure (ICP) before، during and after neurosurgical operations is crucially important. Therefore، trying different methods and drug combinations to attain this goal is an ongoing effort in anesthesiology. In this study we compared two combinations of a narcotic agent with propofol in neurosurgical operations to control intracranial pressure. In this prospective randomized double-blind clinical trial، we enrolled 34 patients with supratentorial brain tumors who were candidates for craniotomy in Alzahra Hospital in Isfahan، Iran from April 2008 to April 2009. The patients were randomly divided into two groups of 17، in whom the first and the second group، respectively، received a combination of «propofol and fentanyl» and a combination of «propofol and remifentanyl» as maintenance of anesthesia. The hemodynamic status، ICP during the surgery، and post-surgical complications in recovery unit were observed for and registered in a questionnaire. Hemodynamic status was similar in both groups and they did not differ in recovery complications except for pain which was more prevalent in remifentanil group (P<0. 03). Although the patients in fentanyl group better responded to the drug for lowering ICP than remifentanyl group، but the difference was not statistically significant. There is no difference between these two anesthetic agent combinations and both could be useful in the anesthesia of neurosurgical operations. However combination of propofol and fentanyl seem to be superior because of more pain relief and a smoother recovery period.

Evaluation of diastolic dysfunction and its relationship with TIMI frame count in patients with stable coronary artery disease referred to Ayatollah Taleghani Hospital in Tehran in the years 2010-2011 is the purpose of this study.

Patients were divided into two groups: case and control. Both groups had chronic angina. Patient information on check list has been studies based on data provided by angiography and echocardiography methods.

Cases had significantly higher values of corrected TIMI frame count (TFC) for the left anterior desending artery (LAD)، TFC for Circumflex artery (Cx) & Right coronary artery (RCA)، (mean TFC P<0. 001). Conventional echocardiography showed significantly lower maximal peak systolic velocity (sm) (cm/s)، Correlation of early diastolic velocity at myocardial segments (Em) & peak systolic velocity at myocardial segments (Sm) with mean TFC in all 3 vessels were significant (P=0/0001). Ratio of maximal early to late diastolic filling (E/A)، in patient with TFC≥ 21 was 0/7 & in patients with TFC≤21 was 1. DT (Deceleration time) had no significant correlation with TFC. Mean of isovolumetric relaxation time (IVRT) in cases was 91 m/s & in controls was 72 m/s Which was higher in patients with mean TFC ≥21. Correlation between mean of angiography and diastolic disfunction was significant.

According to this study diastolic dysfunction which estimated by echocardiography showed significant correlation with TIMI frame count in chronic stable angina patients. Due to simplicity، low cost، quality and reproducibility of this method، this will be helpful.

Acute lymphoblastic leukemia (ALL) is the most common malignancy in childhood، characterized by excess lymphoblasts، and immature white blood cells that are continuously multiplying and overproducing in the bone marrow. The aim of this investigation was to measure the sensitivity of lymphocytes against gamma irradiation in patients with acute lymphoblastic leukemia، and also find out the effect of such irradiations in causing chromosomal abnormalities.

In this investigation performed between April 2010 and July 2011، at the Department of Genetics، Cancer Institute of Iran، we studied the effects of gamma irradiation on the lymphocytes of 20 children with acute lymphoblastic leukemia. The lymphocytes of 30 healthy donors were used to establish as a normal response to gamma irradiation and seven age-matched ataxia telangiectasia patients were recruited as positive control. The chromosomal radiosensitivity was assessed with the G2- and the G0-assay. We compared the mean number of chromosomal abnormalities such as chromosome and chromatid breakages، chromosome and chromatid gaps، and chromatid exchanges in one-hundred metaphases of patients and control groups.

The frequency of chromosomal aberrations was statistically higher among patients with acute lymphoblastic leukemia than the normal controls (P<0. 01). In total، 65% of the patients were sensitive to gamma irradiation، but the remaining 35% were similar to the normal controls. Patients with ataxia telangiectasia showed the highest sensitivity to gamma irradiation (P=0. 001).

Our results showed that a high percentage of patients with acute lymphoblastic leukemia were sensitive to irradiation، meaning that maximum care should be taken during their treatment to avoid unnecessary X-rays or radiotherapies.

Prostate cancer is the most common cancer and the second cause of cancer mortality in men. Although histopathological examination is the gold-standard for its diagnosis، tendency toward less invasive methods is growing. The purpose of this study was to evaluate the relationship between choline plus creatine- to-citrate ratio in magnetic resonance spectroscopy (MRS) with the invasion of prostate cancer in a series of patients with prostate cancer. Totally، 200 patients with pathologically proven prostate cancer were enrolled in this cross-sectional study by a non-probability sampling method in Hazrat Rasul Akram Hospital in Tehran، Iran during 2009-2010. Pathological staging was the gold standard for the diagnosis of prostate cancer while the patients underwent MRS for choline plus creatine- to-citrate ratio determination. MRS and pathological results were compared and analyzed. The mean (±SD) values of choline plus creatine- to-citrate ratio in patients with Gleason scores less than 3، 3 to 4 and greater than 4 were 245. 8±146. 8، 427. 1±173. 6 and 427. 1±173. 6، respectively (P<0. 001). The mean (±SD) values of choline plus creatine- to-citrate ratio in patients with PSA levels less than 4، 4 to 10 and greater than 10 were 180. 7±58. 3، 247±93. 5 and 385. 1±106. 6، respectively (P<0. 001). Choline plus creatine- to-citrate ratio determined by magnetic resonance spectroscopy has a significant relationship with the degree of invasion of prostate cancer and can be used for the staging of the disease.

Ventilator associated pneumonia (VAP) is one of the serious complications of ventilatory support، occurring in ICUs. The aim of this study was to determine various risk factors associated with the acquisition of Acinetobacter infection and its antimicrobial susceptibility pattern. This cross-sectional study was performed in the ICUs of Rasoul-e-Akram Hospital in Tehran، Iran during the year 2011. A total of 51 endobronchial aspirates from intubated patients who had been clinically diagnosed to have VAP were studied bacteriologically. The in vitro susceptibility was determined by disk-diffusion and broth microdilution MIC methods. Out of 51 patients with VAP، 35 (66. 66%) had positive cultures for Acineto-bacter species. In vitro susceptibility test revealed that a high percentage of isolates were resistant to imipenem، piperacillin-tazobactam، third generation cephalosporines، and aminoglycosides. The antimicrobial resistance of gram negative bacteria، particularly Acine-tobacter species، is increasing and preventive measures need to be taken as a matter of urgency.

Scaphoid nonunion remains a challenging problem for hand surgeons. In this study، we assessed the functional outcome of scaphoid nonunion treatment and the influence of a number of variables on it.

In this study we recruited 24 patients with scaphiod nonunion by consecutive sampling at Dr. Ali Shariati Teaching Hospital، in Tehran، Iran in 2008-2011. We examined the patients by antero-posterior (AP) and lateral view radiographies and wrist MRIs. Functional outcome of surgery was scaled according to Mayo wrist and Quick DASH scoring systems.

Among 10 cases with osteonecrosis، there were 7 (70%) cases of radiological union. In 13 (92%) out of 14 cases who had no signs of osteonecrosis، we radiologically confirmed scaphoid union after the treatment. The total union rate was estimated to be 83% at the end of 24 months follow up (P<0. 05).

The results showed that patients with scaphoid nonunion have improved function after surgical treatment.

Balloon atrial septostomy is an emergent procedure in pediatric cardiology. Nowadays، most patients in need of the procedure have acceptable outcomes after surgical repair. Thus، it is important to perform this procedure as safe as possible. By performing early arterial switch operation and prostaglandin infusion، the rate of balloon atrial septostomy has markedly decreased. However، not all centers performing early arterial switch repairs have abandoned atrial septostomy، even in patients who respond favorably to prostaglandin infusion. In total، eight 1- to 15-day old term neonates admitted in Shahid Rajaee Heart Center in Tehran، Iran from October 2009 to February 2011، with congenital heart diseases were scheduled for balloon atrial septostomy. In six cases the procedure was done exclusively under echocardiographic guidance and in two cases with the help of fluoroscopy. Success was defined as the creation of an atrial septal defect with a diameter equal to or more than 5 mm and ample mobility of its margins. Male sex was predominant (87%) and the mean age of the neonates was six days. The diagnosis in all cases was simple transposition of great arteries. The procedure was successful in all patients with any cardiovascular complication. Balloon atrial septostomy is an emergent procedure that can be done safely and effectively under echocardiographic guidance. According to the feasibility of this technique it could be performed fast، safe and effective at bedside، avoiding patient transportation to hemodynamic laboratory or referral center.