Tehran University Medical Journal

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Despite improvement of mechanical ventilation devices for infants, lung injury still causes morbidity and mortality in many cases. To determine the effect of high frequency oscillatory ventilation (HFOV) in infants with severe respiratory failure, 10 neonates were evaluated prospectively. Mean gestational age of these patients was 35 weeks and alveolar-arterial oxygen gradient (A-aDo2) and the ratio of arterial to alveolar oxygen pressure (a/A) immediately before HFO were 610 torr and 0.072 respectively. These neonates were received inspired oxygen concentration of >95% with a mean airway pressure of 12 cm H2O by conventional mechanical ventilation. The A-aDo2 and a/A after 6 and 24 hrs on HFO was not significant in those infants with survived compared with those who died. Comparison of 3 alive neonates with 7 deaths, demonstrate that pulmonary hypoplasia, HMD accompanied with asphyxia, congestive heart failure with pneumonia are associated with poor outcome. The mean a/A ratio during 24hrs of HFO in the alived HMD group was 0.75 compared with 0.25 in those who died. It is possible that we can use this as a prognostic factor in survival. In this study, the positive effect of HFOV was demonstrated in those with no predisposing factors such as pulmonary hypoplasia, congestive heart failure, pneumonia and asphyxia.

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The aim of this investigation is to compare the effect of applying two transcutaneous electrical nerve stimulation (TENS) current with different frequencies (2 Hz & 100 Hz) on Hoffmann reflex recorded from gastrosoleus muscle of healthy people. Forty female subjects between 20 to 30 years of age were participated in this quasi-experimental design. Twenty of them were exposed to the 100 Hz current and the remaining 20 to 2 Hz current on dermatome S1 root. The excitability of the alpha motoneurone was measured by H-reflex amplitude (peak to peak max/2) before and after the application of the TENS current for 30 minutes. The reflex was recorded and at measured before (TO) and after the application of TENS at different times (T1, T% and T10) up to 10 minutes. The mean values were compared by multiple paired T test (alpha=0.00825). The results indicate a considerable decrement in Hoffmann reflex amplitude after application of 100 Hz current in comarison with that of before the application. The effect last for 10 minutes after the TENS application, whereas the application of 2 Hz current results in increment of the Hoffmann reflex amplitude. The 5 and 10 minutes interval test dose not show any significance and the results were attenuated befor 5 minutes. As a conclusion high frequency of TENS (100 Hz) has an inhibitory effect on excitability of alpha motor neurone reflex lasting for 10 minutes, while low frequency of TENS (2 Hz) has an facilatory effect on the same motoneurone with short lasting effect.

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The aim of this investigation is to compare the effect of applying two transcutaneous electrical nerve stimulation (TENS) current with different frequencies (2 Hz & 100 Hz) on Hoffmann reflex recorded from gastrosoleus muscle of healthy people. Forty female subjects between 20 to 30 years of age were participated in this quasi-experimental design. Twenty of them were exposed to the 100 Hz current and the remaining 20 to 2 Hz current on dermatome S1 root. The excitability of the alpha motoneurone was measured by H-reflex amplitude (peak to peak max/2) before and after the application of the TENS current for 30 minutes. The reflex was recorded and at measured before (TO) and after the application of TENS at different times (T1, T% and T10) up to 10 minutes. The mean values were compared by multiple paired T test (alpha=0.00825). The results indicate a considerable decrement in Hoffmann reflex amplitude after application of 100 Hz current in comarison with that of before the application. The effect last for 10 minutes after the TENS application, whereas the application of 2 Hz current results in increment of the Hoffmann reflex amplitude. The 5 and 10 minutes interval test dose not show any significance and the results were attenuated befor 5 minutes. As a conclusion high frequency of TENS (100 Hz) has an inhibitory effect on excitability of alpha motor neurone reflex lasting for 10 minutes, while low frequency of TENS (2 Hz) has an facilatory effect on the same motoneurone with short lasting effect.

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Background: Increase in obesity prevalence in recent years are associated to genetics as well environmental and behavioral factors. Change in dietary patterns including fatty and high density energy foods consumption have been reported to be very important. This study aimed to determine dietary factors (daily energy and macronutrient intakes, energy percentage of macronutrient, energy and macronutrient intakes per kilogram body weight, frequency of cola, natural fruit juice drinking, dairy products except cheese, tomato chips, puff, chocolate and fast food consumption and eating speed) associated to obesity in Ahwaz primary school pupils.

Materials and Methods: Using two stage cluster sampling from 35 Ahwaz primary schools, all 10-11y students who had a BMI 95th percentile of Hosseini et al. (1999) reference, were identified as obese (n=150) and 150 same age and gender pupils (having BMI<85 percentile) were studied. Data on daily energy and macronutrient intakes were collected using 24 hour recall. Frequency of cola, natural fruite juice, dairy products except cheese, tomato chips, puff, chocolate and fast food consumption were obtained by food frequency questionnaire. Eating speed was asked from the pupil mother.

Results: Results indicated that daily energy, protein and carbohydrate intakes were significantly higher in obese students (p<0.05), but daily fat intake and energy percentage of macronutrient had no significant difference between two groups (p>0.05). macronutrient intakes per kilogram body weight were significantly lower in obese group (p<0.001). obese students had significantly higher potato chips and puff consumption (p<0.05). There was no significant difference between other foods consumption (p>0.05). Obese students used to eat faster (p<0.05).

Conclusion: In conclusion, high intakes of energy, protein, carbohydrate, tomato chips and puff and high eating speed were associated to obesity in Ahwaz primary school pupils.

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Background: Radiofrequency has recently been used in treating tonsilar hypertrophy in adults. We evaluated the results of partial resection (volume reduction) of tonsil using this method.
Methods: Twenty patients with tonsilar hypertrophy were enrolled in a quasi-experimental before-after clinical trial. Local anesthesia was achieved by utilizing lidocain spray and then injection of lidocain and epinephrine, then radiofrequency was performed at power=7-8w. Bleeding, pain and need for analgesics were assessed during, immediately, 4, 6, and 8 weeks after operation.
Results: The mean pain scale was 2.68±2.11 according to (VAS) and the mean bleeding amount was 1.16±0.24ml during operation. The mean operation time was 7.81±2.56min. Ten percent of our patients did not have pain immediately after surgery while 55% complained of pains that did not warrant using analgesics and the remaining 35% experienced pains that were alleviated by analgesics. During and immediately after operation 95% of the patients experienced mild bleeding and only one patient (5%) had moderate bleeding (2-5ml). Mild bleeding was only reported in 10% of patients during the first 4 weeks after operation and was not seen in patients in following weeks. The grade of tonsilar hypertrophy decreased in all patients and the mean time of symptom disappearance was 7.81±0.36 in 8 weeks. Finally the mean satisfaction rate of the patients was 66.92±12.5% (ranging from 50% to 80%). Mild complications were reported in 15% of patients.
Conclusion: Radiofrequency is a safe procedure with minimum possible complication rate for tonsilotomy.

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Background: Fibromyalgia has been defined as a constellation of complaints including diffuse chronic pain and the presence of tender points. Its frequency varies from 3% to 20%. This study was conducted to estimate the prevalence of fibromyalgia syndrome in patients who come to the general medical clinic of Dr. Shariati hospital.
Methods: Using a standard questionnaire, all patients who came to the general medical clinic were asked about their ages, presence of diffuse chronic pain, marital status, educational level, living place, number of children and presence of fatigue or sleep disorder by a physician, without any gender or age restriction and without considering their main complaints or their underground diseases. The same physician did a thorough physical examination with special attention to the tender points in order to diagnose fibromyalgia according to the ACR criteria. To rule out other differential diagnosis relevant tests would be ordered for suspected patients.
Results: Among 1004 patients who were assessed, the prevalence of diffuse chronic pain was 14.6% (95%CI: 12.4-16.8). Forty patients 4% (95%CI: 2.9-5.2) suffered from fibromyalgia syndrome, their mean age (±SD) was (48.4±14.9) years.92.5% of these cases were female and 7.5% (3 patients) were male.The prevalence of fibromyalgia among women was 5.98% (95% CI: 4.31-8.06) and among men was 0.78% (95% CI: 0.20- 2.11) (OR=8.1,95%CI:2.48-26.44). There was a meaningful statistical relation between the prevalence of fibromyalgia and gender (P=0.001). There was also a direct statistical relation between the prevalence of fibromyalgia and low educational level (P=0.003). But there was not any relation between fibromyalgia and living place or marital status.Also, there was no relationship between the prevalence of fibromyalgia and having more children (Logestic analysis).82.5% of patients with fibromyalgia suffered from sleep disorders and 92.5% of them complained of fatigue. There was remarkable statistical relations between fibromyalgia syndrome and sleep disorders or fatigue. (P<0.001)
Conclusion: Fibromyalgia syndrome is relatively prevalent among Iranian and in some extents its epidemiological aspects are comparable to those in developed countries. More extensive epidemiologic studies on fibromyalgia is recommended in general population

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Background: Rapid tissue growth and development during puberty increases the need for energy and nutrients. On the other hand, the prevalence of obesity is accelerating among adolescents. Controversies exist regarding meal frequency, obesity and adequacy of nutrients in particular, a more frequent snacking pattern has been associated with overconsumption of calories in children and adolescents and also with greater body weight. We investigated the meal frequency of adolescents in relation to meeting nutrient requirements.
Methods: This cross-sectional study, in the framework of the Tehran Lipid and Glucose Study (TLGS), included 367 boys and girls aged 10-19 years that were randomly selected. Dietary recalls for 48 hours were gathered and participants divided to three groups according to meal frequency group 1, 2 and 3 with <4 meals, 4-6 meals and ≥ 7 meals, respectively. The nutrient intakes were compared with the dietary reference intake (DRI). ANCOVA, Bonferroni and partial correlation by adjusting total energy intake were used for statistical analyses.
Results: The mean age of these 169 boys and 198 girls was 14±3 years old. The weight of the first group was higher by one-third in boys (54±18 vs. 45±13 kilogram, p<0.05). There were no other significant differences in anthropometric indices of the studied subjects, nor was there any difference in the vegetable and meat intake between the groups. But the first group had lower intake of fruits and milk groups (p<0.01). Individuals in all three groups had inadequate intake of calcium, zinc, copper, magnesium, pyridoxine compared with the DRI, although the vitamin C and riboflavin intakes were adequate. Higher meal frequency was associated with sufficient intake of magnesium, vitamin C, riboflavin and pyridoxine.
Conclusion: Adolescents tend to have inadequate intakes of calcium, pyridoxine, zinc, copper, all of which are essential for health and proper growth. Increasing the number of meals per day, without increasing energy intake could help to boost the quality of the diet.

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Background: Resulting from the rough flow of air through the nose and throat during sleep, snoring can arise from transitory obstruction at various levels, rendering the sufferer feeling sleep deprived. A relatively new method using radiofrequency technology, called palatoplasty (somnoplasty), can be used to reduce the size of obstructive tissues in the nose and throat. In this study, we assess radiofrequency palatoplasty in the treatment of snoring.

Methods: This nonrandomized prospective quasi-experimental study included 28 patients who snored at a level considered bothersome to their bed partner. Snoring and drowsiness were each subjectively scored using 20-point visual analogue scales before and after treatment. Radiofrequency energy was delivered to the soft palate either at the midline or in the lateral soft palate 21 patients were treated once and seven patients twice with an interval of at least seven weeks.

Results: The mean age of the patients was 47 (SD=10.7) years, with a range of 25-65 years, 57% were men, and the mean body mass index was 29 (SD=4.5). Sleep apnea in these patients was subjectively rated mild to moderate. After seven weeks of treatment, snoring was improved in 71.4% of patients (p<0.005). The tongue versus pharyngeal size was improved in 34.4% (p<0.005). The mean patient snoring score was significantly improved from 17.39 (SD=3.02) to 11.50 (SD=6.46) (p<0.005). The mean drowsiness score was also significantly reduced from 6.8 (SD=6.9) to 3.93 (SD=4.19) (p<0.005). No persistent negative impact was observed in speech or swallowing. Pain and bleeding was limited.

Conclusions: Radiofrequency palatoplasty is effective in the treatment of snoring and its consequent drowsiness.

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Background: Based on the reports, high frequency of special alleles of HLA class II genes might be associated with susceptibility to or protective from a particular cancer. These alleles might vary depending on the geographical region. Here we investigate the association between alleles of HLA class II genes and breast cancer in Iranian women.
Methods: 100 patients with pathologically proved breast cancer who referred to Cancer Institute, Tehran University of Medical Sciences in Tehran, Iran, were divided to two groups based on ages (40 years old and less/ or more than 40 years old) and were randomly selected and compared with a group of 80 healthy blood donor subjects. HLA class II alleles were determined by amplification of DNA with polymerase chain reaction (PCR) method followed by HLA-typing using sequence-specific primer (SSP) for each allele.
Results: The most frequent alleles in the DR and DQ regions in group 1 (40 years old and less) in comparison with control group were HLA-DQA1*0301 (p=0.002) and HLA-DQB1*0302 (p>0.05). In contrast HLA-DQA1*0505 (p=0.004) had significantly lower frequency in this group compared with control group. Patients of group two (more than 40 years old) had a higher frequencies of HLA-DQA1*0301 (p=0.001) and HLA-DRB1*1303 (p=0.02) and a lower frequency of HLA-DQA1*0101 (p=0.002) compared to healthy control.
Conclusion: These findings provide information of a positive and negative association between certain alleles of HLA class II and breast cancer in our population and also might support that the pattern of inheritance in the early and late onset of breast cancer differ substantially.

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Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background: Distinguishing the origin of ventricular tachycardia (VT) by electrocardiogram (ECG) which is performed in all patients, helps to diagnose the cause of VT before trying invasive procedures. The aim of this study was to compare the ECG findings in patients with VT originating from Right or Left Ventricular Outflow Tracts (RVOT or LVOT).
Methods : Fifty nine patients with VT originating from LVOT or RVOT were selected for this cross-sectional study. The patients were recruited while they were attending Shahid Rajaei Hospital in Tehran, Iran in 2009-2010 for catheter ablation. The participants were evaluated for the prevalence of LVOT and RVOT and were compared for the success rate of radiofrequency catheter ablation.
Results : Out of 59 patients, 44.1% were male and 55.9% were female. The mean age of the participants was 41.67 (SD=13.76) years. QRS transition and notch in ECGs were significantly different (respectively, P=0.027 and P=0.007) between patients with LVOT and RVOT. R-to-QRS duration in precordial leads was significantly longer in patients with LVOT than those with RVOT [0.81 (SD=0.06) ms vs. 0.69 (SD=0.16), P=0.015]. Successful ablation was performed in 73.2% of patients with RVOT versus 93.3% of those with LVOT, but despite a higher rate the differences were not statistically significant (P=0.215).
Conclusion: In this study, RF catheter ablation was successful like other studies on patients with ventricular tachycardia and RVOT VT and LVOT VT had significant differences in notch, QRS transition and R-to-QRS duration in precordial leads which are important in differentiating between the two conditions.

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Background: Osteoid osteoma is a painful benign osteoblastic lesion occurring mainly in the long bones. On the one hand, some studies have declared that post-treatment CT cannot determine the success or failure of radiofrequency ablation, on the other hand, some studies have stated that imaging follow-up can be helpful or even mandatory in some cases. The present study aims to evaluate Osteoid Osteoma's imaging features before or after radiofrequency ablation with or without curettage and during the follow-up period.
Methods: In this retrospective and cross-sectional study, we reviewed twenty seven Osteoid Osteoma patients with radiofrequency ablation who were assessed via drilling with or without curettage from March 2015 to December 2019 at Nemazi Hospital, Shiraz University of Medical Sciences.