Rev Invest Clin
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Comparative Study
An assessment of immediate DNA damage to occupationally exposed workers to low dose ionizing radiation by using the comet assay.
Several cytogenetic studies have shown an increased frequency of chromosomal aberrations for workers exposed to low dose ionizing radiation, however the dose, type of radiation and management vary among the areas of work; it is possible that this variation may generate different quantity of DNA damage, detectable within the first hours after exposure of the personnel. In this study we assessed early DNA lesions caused by exposure to low doses of ionizing radiation in 41 workers from the departments of Radiology, Nuclear Medicine and Radiotherapy and a group of 20 healthy unexposed individuals, all from the same Institution. ⋯ All the workers occupationally exposed showed an increase in DNA fragmentation after the workday. The amount of radiation in all three services is different, in Nuclear Medicine and Radiotherapy the workers showed a greater monthly dose of exposure and greater DNA damage than the Radiology workers. The longer tails were observed in Nuclear Medicine where radionuclides are used; these radioactive substances are handled and administered to patients orally or intravenously by the workers, which implies a different type of exposure and radiation, this may explain the differences found in this study. Most of the DNA damage detected by the comet assay is repaired, however a part of it may result in stable chromosomal rearrangements that may represent a long-term health risk. It is important to sensitize exposed workers on their responsibility of working with radiation and the improvement of the hospital safety practices.
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Case Reports
Bicuspid aortic valve: a synergistic factor for aortic dilation and dissection in Marfan syndrome?
Patients with either Marfan syndrome or bicuspid aortic valve are at increased risk for aortic dilation and dissection, but occurrence of both conditions has barely been reported. Whether bicuspid aortic valve adversely impacts the cardiovascular outcome in Marfan syndrome patients is unknown. The objective was to investigate the prevalence of bicuspid aortic valve and to define whether its combined presence would adversely impact cardiovascular outcome in patients with Marfan syndrome. ⋯ Presence of bicuspid aortic valve shows trends for association with aortic dilation (Odds ratio [OR] 4.2; 95% Confidence interval [95% CI] 0.2-81), and aortic dissection (OR 5.5; 95% CI 0.7-42), while negative association with the Walker-Murdoch sign (OR 0.07; 95% CI 0.006-0.73) was found. Prevalence of bicuspid aortic valve in patients with Marfan syndrome patients is 4.5%. While it is intriguing and even intuitive that the concurrence of both conditions would lead to more aggressive aortic disease, a true synergistic role for aortic wall weakening cannot be supported.