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BACKGROUND: An alternative approach to the traditional model of radiologists interpreting screening mammography is necessary due to the shortage of radiologists to interpret screening mammograms in many countries. METHODS: We evaluated the performance of 15 Mexican radiographers, also known as radiologic technologists, in the interpretation of screening mammography after a 6 months training period in a screening setting. Fifteen radiographers received 6 months standardized training with radiologists in the interpretation of screening mammography using the Breast Imaging Reporting and Data System (BI-RADS) system. A challenging test set of 110 cases developed by the Breast Cancer Surveillance Consortium was used to evaluate their performance. We estimated sensitivity, specificity, false positive rates, likelihood ratio of a positive test (LR+) and the area under the subject-specific Receiver Operating Characteristic (ROC) curve (AUC) for diagnostic accuracy. A mathematical model simulating the consequences in costs and performance of two hypothetical scenarios compared to the status quo in which a radiologist reads all screening mammograms was also performed. RESULTS: Radiographer's sensitivity was comparable to the sensitivity scores achieved by U.S. radiologists who took the test but their false-positive rate was higher. Median sensitivity was 73.3 % (Interquartile range, IQR: 46.7-86.7 %) and the median false positive rate was 49.5 % (IQR: 34.7-57.9 %). The median LR+ was 1.4 (IQR: 1.3-1.7 %) and the median AUC was 0.6 (IQR: 0.6-0.7). A scenario in which a radiographer reads all mammograms first, and a radiologist reads only those that were difficult for the radiographer, was more cost-effective than a scenario in which either the radiographer or radiologist reads all mammograms. CONCLUSIONS: Given the comparable sensitivity achieved by Mexican radiographers and U.S. radiologists on a test set, screening mammography interpretation by radiographers appears to be a possible adjunct to radiologists in countries with shortages of radiologists. Further studies are required to assess the effectiveness of different training programs in order to obtain acceptable screening accuracy, as well as the best approaches for the use of non-physician readers to interpret screening mammography.

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Venezuelan equine encephalitis virus (VEEV) is an emerging pathogenic alphavirus that can cause significant disease in humans. Given the absence of therapeutic options available and the significance of VEEV as a weaponized agent, an optimization effort was initiated around a quinazolinone screening hit 1 with promising cellular antiviral activity (EC50 = 0.8 µM), limited cytotoxic liability (CC50 > 50 µM), and modest in vitro efficacy in reducing viral progeny (63-fold at 5 µM). Scaffold optimization revealed a novel rearrangement affording amidines, specifically compound 45, which was found to potently inhibit several VEEV strains in the low nanomolar range without cytotoxicity (EC50 = 0.02-0.04 µM, CC50 > 50 µM) while limiting in vitro viral replication (EC90 = 0.17 µM). Brain exposure was observed in mice with 45. Significant protection was observed in VEEV-infected mice at 5 mg kg(-1) day(-1) and viral replication appeared to be inhibited through interference of viral nonstructural proteins.

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The benefit of early breast cancer detection is the foundation for programs around the globe to reduce morbidity and mortality related to breast cancer. These programs range from educational programs targeted to women and health professionals to organized or opportunistic screening programs that target specific age groups of women.Modern mammography programs tend to follow the protocols from the randomized clinical trials, but there is variation in key program elements such as the age groups invited to screening, the screening interval, performance indicators, and the uptake rate. Until recently, the emphasis on early breast cancer detection was limited to mammography, but the steady rise in incidence and mortality in low and medium resource countries, where mammography may be unaffordable, has led to a renewal in emphasizing the incremental value of downsizing palpable tumors through physical exams. There is consensus that programs should be designed based on disease burden and available resources, but that even in low resource countries there are opportunities to reduce breast deaths through earlier diagnosis and effective treatment. Screening programs are most effective when they are organized, and program planners should consider WHO criteria and local input data as a basis for tailoring screening programs to the needs of their population.

El beneficio de la detección temprana del cáncer de mama es el fundamento para programas alrededor del mundo que buscan reducir la morbilidad y mortalidad relacionada con este padecimiento. Estos programas abarcan desde los de tipo educativo, orientados a mujeres y profesionales de la salud, hasta programas de monitoreo organizados u oportunistas que tienen como objetivo grupos específicos de edad. Los programas modernos de mastografía tienden a seguir protocolos para estudios clínicos aleatorios,pero hay una variación en elementos clave como los grupos de edad invitados a participar, el intervalo para el monitoreo, indicadores de desempeño, y la tasa de captación. Hasta hace poco, el énfasis en la detección temprana del cáncer estaba limitado a la mastografía, pero el incrementoen la incidencia ymortalidad en países de recursos bajos a medios, donde las mastografías no son asequibles, ha llevado a un renovado énfasis en el valor de los exámenes físicos. Existe un consenso en cuanto a que los programas deben estar diseñados basándose en la carga de la enfermedad y los recursos disponibles, pero incluso los países con recursos más limitados tienen oportunidades para reducir las muertes de cáncer de mama a través de un diagnóstico oportuno y un tratamiento eficaz. Los programas de detección son más eficaces cuando están organizados, y los planeadores del programa deben considerar los criterios de la OMS y la información local como bases para ajustarlos a las necesidades de la población.

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The benefit of early breast cancer detection is the foundation for programs around the globe to reduce morbidity and mortality related to breast cancer. These programs range from educational programs targeted to women and health professionals to organized or opportunistic screening programs that target specific age groups of women. Modern mammography programs tend to follow the protocols from the randomized clinical trials, but there is variation in key program elements such as the age groups invited to screening, the screening interval, performance indicators, and the uptake rate. Until recently, the emphasis on early breast cancer detection was limited to mammography, but the steady rise in incidence and mortality in low and medium resource countries, where mammography may be unaffordable, has led to a renewal in emphasizing the incremental value of downsizing palpable tumors through physical exams. There is consensus that programs should be designed based on disease burden and available resources, but that even in low resource countries there are opportunities to reduce breast deaths through earlier diagnosis and effective treatment. Screening programs are most effective when they are organized, and program planners should consider WHO criteria and local input data as a basis for tailoring screening programs to the needs of their population.

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Previous studies have documented significant international variations in colorectal cancer rates. However, these studies were limited because they were based on old data or examined only incidence or mortality data. In this article, the colorectal cancer burden and patterns worldwide are described using the most recently updated cancer incidence and mortality data available from the International Agency for Research on Cancer (IARC). The authors provide 5-year (1998-2002), age-standardized colorectal cancer incidence rates for select cancer registries in IARC's Cancer Incidence in Five Continents, and trends in age-standardized death rates by single calendar year for select countries in the World Health Organization mortality database. In addition, available information regarding worldwide colorectal cancer screening initiatives are presented. The highest colorectal cancer incidence rates in 1998-2002 were observed in registries from North America, Oceania, and Europe, including Eastern European countries. These high rates are most likely the result of increases in risk factors associated with "Westernization," such as obesity and physical inactivity. In contrast, the lowest colorectal cancer incidence rates were observed from registries in Asia, Africa, and South America. Colorectal cancer mortality rates have declined in many longstanding as well as newly economically developed countries; however, they continue to increase in some low-resource countries of South America and Eastern Europe. Various screening options for colorectal cancer are available and further international consideration of targeted screening programs and/or recommendations could help alleviate the burden of colorectal cancer worldwide.

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