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Low-dose Radiation (low-dose + radiation)
Selected AbstractsRetention of Quality and Nutritional Value of 13 Fresh-Cut Vegetables Treated with Low-Dose RadiationJOURNAL OF FOOD SCIENCE, Issue 7 2008X. Fan ABSTRACT:, Improving the microbial safety while maintaining quality of fresh fruits and vegetables will increase consumer confidence in fresh produce. This study was conducted to investigate the effects of irradiation at 1 kGy, a dose that potentially inactivates E. coli O157:H7 by 5 logs, on the quality of 13 common fresh-cut vegetables: iceberg, romaine, green and red leaf lettuce, spinach, tomato, cilantro, parsley, green onion, carrot, broccoli, red cabbage, and celery. The results showed that the appearance of irradiated samples was similar to the nonirradiated ones except that irradiated carrots, celery, cilantro, and green onions had higher appearance scores than corresponding nonirradiated vegetables. There was no difference in the instrumental texture between irradiated samples and nonirradiated ones. The aroma of several irradiated vegetables was significantly better than controls after 14-d storage, because these control samples decayed or senesced. The 1 kGy irradiation did not affect vitamin C content of most vegetables; however, irradiated green and red leaf lettuce had 24% to 53% lower vitamin C contents than the controls. Our results suggest that most fresh-cut fruits and vegetables tested can tolerate up to 1 kGy irradiation without significant losses in any of the quality attributes. [source] Multiple Basal Cell Carcinomas Developed After Radiation Therapy for Tinea Capitis: A Case ReportDERMATOLOGIC SURGERY, Issue 7 2001Pelin Ekmekçi MD Development of skin neoplasms is the most important complication of radiation therapy. There are contradictive reports about the type of these neoplasms. Squamous cell carcinomas are considered the most frequent tumors arising on chronic radiodermatitis areas, but recent studies have demonstrated that the type of neoplasm occurring in response to ionizing radiation exposure depends on several factors. Herein we report a patient who had received low-dose radiation for the treatment of tinea capitis and developed multiple basal cell carcinomas in the radiated areas after a long latent period of 53 years. [source] Intra-tumoral Salmonella typhimurium induces a systemic anti-tumor immune response that is directed by low-dose radiation to treat distal diseaseEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 7 2008Francesca Avogadri Abstract Salmonella typhimurium is a facultative anaerobic bacterium able to multiply preferentially in tumors and inhibit their growth. The mechanisms through which Salmonella exerts its anti-cancer properties are not fully understood. We recently showed that intra-tumoral Salmonella injection results not only in the regression of even bulky tumor masses, but also impacts on the growth of distant untreated lesions. Here we describe how Salmonella exerts its systemic anti-cancer effects and means to potentiate them. The outburst of an early inflammatory reaction in the treated tumor promotes the development of an immunostimulatory cytokine environment both locally and in the draining lymph node. Within the next 10,days, an efficient cross-presentation of endogenous tumor antigens by dendritic cells at the tumor-draining lymph node leads to the priming of effective anti-tumor CD8+ T cell responses. This potentially broadly reactive T cell repertoire can be directed to other pre-established melanomas by low-dose radiotherapy enhancing the Salmonella anti-cancer effect. We demonstrate that Salmonella -based therapy coupled to low-dose radiotherapy dampens tumor immune escape mechanisms at different levels and allows controlling systemic disease in a CD8+ T cell-dependent manner. [source] Evaluating Acceptance and Understanding of Risk in the Emergency Department:Are All Risk Statements Created Equally?ACADEMIC EMERGENCY MEDICINE, Issue 4 2002James A. Feldman MD Abstract. Objective: To determine whether mathematically equivalent but conceptually different presentations of risk from radioactive isotope exposure might affect the rate of agreement to participate in a hypothetical research study. Methods: This was a prospective study of consenting English-speaking subjects more than 18 years of age who were asked whether they would agree to participate in a mock study when presented with six mathematically equivalent statements of research-related risk. Participants were classified as recognizing the equivalence of the risk statements if they accepted all or refused all of the risk statements. Results: Three hundred forty-six subjects were enrolled. There were 55 subjects (16%; 95% CI = 12% to 20%) who refused all of the six risk statements, and 23 participants (6.7%; 95% CI = 4% to 9%) who accepted all of the given risk statements. Most of the participants (77%; 95% CI = 73% to 82%) did not recognize that the six risk statements were equivalent and agreed to some, or did not understand some of the risk statements. In stepwise multivariate logistic regression, being white, being of older age, and having higher education were associated with a higher likelihood of accepting or rejecting all six of the risk statements. Conclusions: Ethnicity, age, and education affected whether patients recognized the equivalence of six risk statements for a hypothetical study of low-dose radiation. Risk acceptance may be more likely when familiar concepts are used to express research risks. Researchers must focus on strategies that enhance the understanding of research risks and address the reasons for nonparticipation by subjects who are younger, of different ethnic or cultural background, or of lower education. [source] Chronic radiation exposure in the Rivne-Polissia region of Ukraine: Implications for birth defectsAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 5 2010Kelsey Needham Dancause Objectives: The health effects of chronic low-dose radiation exposure remains a controversial question. Monitoring after the Chernobyl nuclear accident in Ukraine suggested that chronic low-dose radiation exposure was not linked to cancer mortality among the general population. However, elevated rates of birth defects in contaminated compared to uncontaminated regions suggest that exposure to radiation in utero might impact development and that chronic radiation exposure might represent an underestimated risk to human health. Methods: We sought to determine current radiation exposure routes in Rivne-Polissia, a region of Ukraine contaminated by the Chernobyl accident. This represents a first step toward comprehensive studies of the effects of chronic radiation exposure on human health. We designed and administered a dietary and activity survey to 344 women in Polissia. We assessed types and sources of food consumed, types of outdoor activities, and alcohol intake. Results: Alcohol intake was low and alone does not account for the observed high rates of birth defects. Wild foods, especially mushrooms and berries, and locally produced foods, especially milk related, were major radiation exposure routes. Additionally, women were exposed to radiation through inhalation while burning grasses and potato vines in fields, and wood for cooking and heating. Conclusions: Twenty four years after the Chernobyl accident, women continue to be chronically exposed to low-dose radiation at levels exceeding current recommendations. This might contribute (especially synergistically with alcohol consumption and micronutrient deficiencies) to higher prevalence of birth defects in areas of Ukraine with high levels of radiation contamination compared to uncontaminated areas. Am. J. Hum. Biol. 22:667,674, 2010. © 2010 Wiley-Liss, Inc. [source] An Interdisciplinary Initiative to Reduce Radiation Exposure: Evaluation of Appendicitis in a Pediatric Emergency Department With Clinical Assessment Supported by a Staged Ultrasound and Computed Tomography PathwayACADEMIC EMERGENCY MEDICINE, Issue 11 2009Naresh Ramarajan MD Abstract Objectives:, In the emergency department (ED), a significant amount of radiation exposure is due to computed tomography (CT) scans performed for the diagnosis of appendicitis. Children are at increased risk of developing cancer from low-dose radiation and it is therefore desirable to utilize CT only when appropriate. Ultrasonography (US) eliminates radiation but has sensitivity inferior to that of CT. We describe an interdisciplinary initiative to use a staged US and CT pathway to maximize diagnostic accuracy while minimizing radiation exposure. Methods:, This was a retrospective outcomes analysis of patients presenting after hours for suspected appendicitis at an academic children's hospital ED over a 6-year period. The pathway established US as the initial imaging modality. CT was recommended only if US was equivocal. Clinical and pathologic outcomes from ED diagnosis and disposition, histopathology and return visits, were correlated with the US and CT. ED diagnosis and disposition, pathology, and return visits were used to determine outcome. Results:, A total of 680 patients met the study criteria. A total of 407 patients (60%) followed the pathway. Two-hundred of these (49%) were managed definitively without CT. A total of 106 patients (26%) had a positive US for appendicitis; 94 (23%) had a negative US. A total of 207 patients had equivocal US with follow-up CT. A total of 144 patients went to the operating room (OR); 10 patients (7%) had negative appendectomies. One case of appendicitis was missed (<0.5%). The sensitivity, specificity, negative predictive value, and positive predictive values of our staged US-CT pathway were 99%, 91%, 99%, and 85%, respectively. A total of 228 of 680 patients (34%) had an equivocal US with no follow-up CT. Of these patients, 10 (4%) went to the OR with one negative appendectomy. A total of 218 patients (32%) were observed clinically without complications. Conclusions:, Half of the patients who were treated using this pathway were managed with definitive US alone with an acceptable negative appendectomy rate (7%) and a missed appendicitis rate of less than 0.5%. Visualization of a normal appendix (negative US) was sufficient to obviate the need for a CT in the authors' experience. Emergency physicians (EPs) used an equivocal US in conjunction with clinical assessment to care for one-third of study patients without a CT and with no known cases of missed appendicitis. These data suggest that by employing US first on all children needing diagnostic imaging for diagnosis of acute appendicitis, radiation exposure may be substantially decreased without a decrease in safety or efficacy. [source] | ||||||||||