Tehran University Medical Journal

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AVNRT, (Atrioventricular nodal reentry tachycardia), atrial tachycardia and atrial flutter are 3 kinds of supraventricular tachycardia, which their mechanism are explained based on reentry. A 60-years-old man is presented with all of the above-mentioned arrhythmias, responsive to intravenous injection of adenosine. Radiofrequency ablation of the slow pathway territories cured all of them. Therefore, we suggest that there was a common pathway among all kinds of these arrhythmias, which were ablated with single RF lesion.

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The effects of taking snacks on the learning ability and educational achievement of elementary school children in district 18 of Tehran educational organization were examined in the school year 1997-98. Other factors such as grade, nutritional status, breakfast eating habits and snack eating habits in the school were also studied. For this purpose 236 boys were selected by random sampling in 4 different schools. The children were randomly assigned to a group, with a low calorie snack (119 subjects), and a low-calorie control group (117 subjects), and then given 3 cognitive functions tests. The test were repeated after 4 months. The data were collected by questionnaires and included family socio-economic conditions, nutritional status and dietary habit of the children. Also, the grades of the major courses and scores of cognitive tests were collected, and the effects of treatment on the mean grades and scores differences were determined by T-test and analysis of variance (ANOVA). Our findings are presented as follow: The experimental and control groups were similar in the initial assessment. 7.1% of the students were stunted based on height-for-age classification (NCHS). The intervention led to an increase in tests scores, but the increase was only significant in the case of the short-term memory test (P<0.03). The findings of the study showed that the intervention was effective on short-term memory and since short-term memory function in memorization process and retrieval of subjects form long-term memory and congenitive functions, we can conclude that the food intervention with an energy lower than 10% of recommended dietary needs increases learning ability level of the subjects. Stunting and the habit of eating breakfast were related to educational performance of students. Therefore implementation of such programs in the community, such as food intervention and nutritional education may be effective.

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Introduction: Ischemic heart disease is the most common cause of mortality in developed countries. CABG (Coronary Artery Bypass Graft) is one of the therapeutic methods in ischemic heart disease.

Methods and Materials: Considering the increased incidence of coronary artery disease in Iran, and with increased rate of CABG, we performed a cross sectioned study (1996-1999). In 635 patients 467 male (73.5 percent), 168 female (26.5 percent) about risk factors of mortality after CABG in cardiac surgery department "Imam Khomeini hospital. 20 risk factors were included in our study: age, gender, smoking, family history, diabetes mellitus, morbid obesity, hypercholesterolemia, hypertension, palpitation, renal failure COPD, (chronic obstructive pulmonary disease), history of myocardial infarction, CHF, angina, cerebral vascular disease, pace maker, Ejection fraction<40 percent, history of PTCA, history of CPR, and coronary endarterectomy.

Results: Cigarette smoking (P=0.40), CHF in female (P=0.003). Endarterectomy in both gender (P=0.0001). Pace maker in both gender (P=0.00006), palpitation in both gender (P=0.0001). CPR in both gender (P=0.0000001), were associated with increased risk of mortality after CABG.

Conclusion: We found that, endarterctomy, cigarette smoking, CHF. Pace maker, CPR, and palpitation are important risk factors for mortality after CABG.

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Background: Food security is defined as access, for all people at all times, to enough food for an active and healthy life. Food security includes: 1) the ready availability of nutritionally-adequate and safe food, and 2) an assured ability to acquire acceptable foods in socially acceptable ways. The increase in childhood as well as adulthood obesity and food insecurity has caused many recent investigations on obesity, food insecurity and some associated factors. However, there appears to be a lack of published information regarding some factors affecting obesity and food insecurity. This study aimed to determine the prevalence obesity and food insecurity and some associated factors among Yazd province primary school students in Iran.

Methods: Using two-stage cluster sampling, a total of 3245 students (1587 boys and 1658 girls), aged 9-11 years, were randomly selected from primary school pupils in Yazd, Iran. From these, 187 students having BMIs ≥95^th percentile, as defined by Hosseini et al. (1999), were identified as obese and 187 pupils of the same age and gender having BMIs between the 15^th and 85^th percentiles were selected as controls. Data were collected using 24-hour food-recall and USDA food insecurity questionnaires.

Results: We found that the prevalence of obesity among students aged 9-11 years was 13.3%, and the prevalence of food insecurity was 30.5%. Daily energy intakes, compared to those recommended by the RDA, carbohydrate intake and energy percentages from proteins and carbohydrates were higher in obese children, and all macronutrient intakes per kilogram of body weight were significantly higher. An association between obesity and food insecurity was observed with adjusted fat intake.

Conclusion: In conclusion, the prevalence of obesity and food insecurity is high among Yazd primary school students, and high-level intakes of energy, protein, carbohydrate are associated with obesity. Furthermore, variation in the rate of fat intake is a relative factor for food insecurity.

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Background: Hepatitis B vaccination has been included in routine immunization of all individuals according to WHO recommendations since 1991. Despite successful coverage, 3-5% of recipients fail to mount a desirable protection level of Ab. Vaccine failure results from: emergence of mutation, immune failure of individuals, decrease in vaccine potency, and etc. The quality of Hepatitis B vaccine should be evaluated by a reliable method.

Methods: The amount of vaccine antigen was measured through the in vitro assay of Hepatitis B vaccines which consists of multiple dilutions of the reference material and samples. The preparations were evaluated by Elisa to determine the amount of HBsAg. The data were analyzed by parallel-line analysis software. The in vivo assay was performed by inoculating multiple doses of the reference and sample preparations in Balb/c mice. A control group was also inoculated with vaccine matrix. Four weeks later, the mice sera were evaluated to determine the presence of antibodies against Hepatitis B by Elisa method. The data were analyzed by Probit analysis software.

Results: Both methods were set up in our laboratory by which different batches of Hepatitis B vaccine were evaluated. It was observed that In vivo and In vitro methods provide comparable results. Therefore we can use the in vitro method for routine testing of HB vaccine quality control.
Conclusion: In vitro method can be used in place of In vivo method because of its time and cost-effectiveness. Moreover, since no animals are used in in vitro method, it complies well with the 3R concept (Reduction, Refinement, and Replacement of animal testing) and the current tendency to use alternative method.

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Background: Cognitive problems in patients with post-traumatic stress disorder (PTSD) include poor concentration and impaired memory. Prevalence of PTSD in all aspects of life is 8% in USA. Regarding the importance of memory in functional levels, this study was performed to review memory status in these patients.

Methods: Fifty male war veterans with PTSD and major depression and 50 male non-veterans with depression participated in this study performed at psychiatric outpatient ward in Baqiyatallah hospital during 2008-2009. The patients met the DSM-IV diagnostic criteria. Depression severity, sex, age, educational level, and marital status were matched in both groups. A psychologist completed demographic and Mississippi questionnaires, PTSD checklist (PCL), beck depression Inventory and wechsler memory scale. The collected data were analyzed using SPSS software (version 11.0). A P-value smaller than 0.05 was considered significant.

Results: The mean age of the veterans and non-veterans was 43.9±4.7 and 42±9.4 years, respectively. Memory status did not differ between the two groups (P>0.05). There was no statistically significant correlation between duration and severity of PTSD with memory impairment (P>0.05). A negative correlation was found between personal and general information with re-experiencing in the veterans (P<0.05). Impaired memory was correlated with age greater than 45, educational level lower than high school diploma, severity of depression and longer participation in war.

Conclusion: Although both PTSD and major depression affected memory, but memory status did not differ between patients with PTSD and depression and patients with chronic depression.