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 Background & Objectives:�Barrett’s esophagus is the most severe complication of gastroesophageal reflux which may lead to Adenocarcinoma of the esophagus. The epidemiologic aspects of this condition is not completed studied in Iran. The aim of this study is to appraise short segment Barrett’s esophagus in patients which are evaluated due to their reflux related symptoms in a university endoscopy center.

 Methods:�During this cross-sectional study, short segment Barrett’s esophagus was investigated in 100 consequent patients with reflux symptoms (heart burn and/or acid regurgitation) for at least one year. After obtaining their consent for upper endoscope, they were studied interms of short barrett esophagus Four biopsies from esophageal side of gastroesophageal junction for histologic evaluation, and one from antrum for rapid urease test used for Helicobacter pylori were obtained. Barrett’s esophagus was confirmed by appearance of intestinal metaplasia by two pathologists.

  Results: Among 100 eligible subjects, 39 patients were male and 61 were female with a mean (±SD) age of 42.31±15.12 years. Prevalence of short segment Barrett’s esophagus in this study was 8%. Barrett’s esophagus was not related to gender, symptoms and their severity but was significantly more frequent in patients experienced their symptoms for more than 5 years. Barrett’s esophagus was not related to the presence of esophagitis. Infection with Helicobacter pylori was related to less esophagitis but was not related to presence of Barrett’s esophagus.

 Conclusion:�According to the high prevalence of Barrett’s esophagus in subjects with reflux related symptoms in our region, upper gastroesophageal endoscopic evaluation of patients with symptoms more than 5 years is recommended even before age 40. Patients may benefit from Concentration the attention of the endoscopist for taking biopsies.

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Background & Objectives: Venous thromboembolism is a common disorder that is difficult to diagnose clinically but carries significant mortality if untreated. Many diagnostic imaging algorithms for the detection of PTE, including ventilation perfusion lung scan, Doppler ultrasonography of lower extremity and pulmonary CT angiography. This study's aim was the comparison of Doppler ultrasonography of lower extremity with perfusion -ventilation lung scan in patients suspected for pulmonary emboli and finding the best approach for diagnosis of the suspected pulmonary emboli.
Methods: One hundred twenty patients of suspected pulmonary embolism referred by internists to Doppler ultrasonography of lower limbs Department of Imam's Khomeini Hospital were studied. The patients were studied within 48 hour post suspected pulmonary emboli and evaluated with V/Q scan and Doppler ultrasonography.
Results: The prevalence of DVT in lower limbs of patients suspected of pulmonary emboli was %37.5. Results of lung scan in patients suspected pulmonary emboli are as below: High probability in %17.5, intermediate probability in %27.5, low probability in %41.5 and normal in %13.5 Results of lung scan in patients suspected  for pulmonary embolism with DVT are as follow: High probability in %24.4, Intermediate probability in %33.3, low probability in %26.7 and normal in %15.6. Mean age in patients with and without DVT Was 52.53 14.13 and 56.22 17.63 year respectively.
Conclusion: Patients suspected for pulmonary emboli with normal lung scan needs more assessment for DVT in lower extremity with Doppler ultrasonography. Normal Doppler ultrasonography of lower extremity doesn't exclude performing lung scan for approving pulmonary emboli. Doppler ultrasonography and lung scan both need evaluating patients suspected for pulmonary embolism.

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  Background & Objectives : Several studies have been conducted to explore anti-HIV drugs. Discovery and study of novel anti-HIV-1 compounds need live viruses and has serious biosafety concerns. In this research we reported a novel and safe system for assaying the cytopathic effects of HIV by using single cycle replicable (SCR) HIV-1 virions.

  Methods: To produce the SCR HIV-1 virions, pMD2G, pmzNL4-3 and pSPAX2 plasmids were co-transfected into HEK293T cells. Different amount of SCR virions were used to infect target cells (MT-2). Within the infected cells, the number of formed syncytia was counted under the light microscopy. The lethal effects of the SCR HIV virions were measured using XTT proliferation assay.

  Results: Formation of syncytia among SCR HIV infected cells was detectable 24 hours after infection. Highest amount of syncytia was seen 72 hours after infection. Increase in the amount of virions caused increasing of syncytia and the cytopathic effects of SCR HIV-1. Infection with more than 1600ng P24 SCR HIV decreased the syncytium formation and viability of all cells. The calculated IC50 (50 percent inhibitory capacity) for nevirapine and BMS806 using this method was 50nM and 30nM, respectively.

  Conclusion: SCR HIV-1 virions are replicable only for one cycle. Using these virions can improve the safety of HIV researches. Herein, we optimized the assaying of HIV induced cytopathic effects by using SCR HIV-1 (NL4-3) virions. The accuracy of this method was accepted by quantifying the anti-HIV-1 effects of nevirapine and BMS806 by (SCR) HIV-1 virions.