New RNA species is produced by alternate polyadenylation following rearrangement associated withCAD gene amplification

Mammalian cells selected to resist N-(phosphonacetyl)-L-aspartate (PALA) contain amplified copies of the CAD gene. While a single 7.9-kb mRNA species is detected in PALA-sensitive and most PALA-resistant cell lines, two RNA species (7.9 and 10.2 kb) are detected in two related drug-resistant mutants presumably derived from the same parental cell. In this report we show that the 10.2-kb RNA is produced as a direct consequence of a sequence rearrangement adjacent to the 3 end of the CAD gene in these cell lines. A CAD gene containing the sequence rearrangement was cloned from one of these lines and found to produce both RNA species when transfected into CAD-deficient cells. DNA sequencing and S₁ analysis demonstrate that the 10.2-kb RNA is produced by alternative polyadenylation rather than by alternative splicing. Sequence analysis also reveals that several consensus poly(A) addition signals (AATAAA) were brought into close proximity to the CAD gene by virtue of the rearrangement. While sequences adjacent to each of the polyadenylation signals contain additional features postulated to be important for the selection of the site of poly (A) addition, S₁ mapping analysis indicates that only one of the polyadenylation signals is used. A comparison of all of these sites suggests that multiple sequence motifs are required to form a functional polyadenylation and cleavage signal.     

Student evaluation of the clinical 'curriculum in action'

AIM: To examine how students' evaluations of the environment, process and outcome of clinical learning interrelated and correlated with assessment results. METHOD: A post hoc study in the 3rd of 5 years in a student-centred, horizontally integrated, objective-based medical curriculum. In the last week of each module, students evaluated what they had learned and how they had learned it using a previously validated, web-based scale. The interrelationships between scale variables and their relationships with summative assessment results were tested using factor analysis, correlation analysis and stepwise multiple regression analysis. RESULTS: Student evaluation yielded 4 summary measures: 2 reflected learning outcomes ('real patient learning' and 'curriculum coverage'), 1 reflected process ('quality of instruction') and 1 reflected environment ('conditions for learning'). They fitted a causal model according to which instruction, conditions for learning and curriculum coverage favoured real patient learning. Real patient learning was rated higher in women than men, and the measures were associated more strongly in women. Performance in end-of-year summative assessments was predicted strongly by mid-year performance but by no other measure. CONCLUSIONS: Students' evaluations of their learning environment and instructional processes correlated with their assessments of 2 outcomes of the curriculum in action: curriculum coverage and real patient learning. There was little shared variance between those measures and students' performance in summative assessments. Given its formative potential, students' evaluation of their curriculum in action could play a useful part in learner-centred clinical education. There is a possibility, which needs further research, that women's evaluations have greater predictive validity than men's. Assessment performance should be regarded not as a solitary gold standard but as just 1 measure of educational outcome.     

Physical activity in men and women with arthritis National Health Interview Survey, 2002

BACKGROUND: Regular physical activity in persons with arthritis has been shown to decrease pain, improve function, and delay disability. This study estimates the national prevalence of leisure-time physical activity and identifies factors associated with physical inactivity in adults with arthritis. METHODS: Data from the 2002 National Health Interview Survey were analyzed in 2004-2005 to estimate the proportion of adults with arthritis meeting four physical activity recommendations put forward in Healthy People 2010 and one arthritis-specific recommendation established by a national expert panel in arthritis and physical activity. Multivariate logistic regression was used to evaluate the association between inactivity and sociodemographic factors, body mass index, functional limitations, social limitations, need for special equipment, frequent anxiety/depression, affected joint location, joint pain, physical activity counseling, and access to a fitness facility. RESULTS: Adults with arthritis were significantly less likely than adults without arthritis to engage in recommended levels of moderate or vigorous physical activity, and 37% of adults with arthritis were inactive. In both men and women with arthritis, inactivity was associated with older age, lower education, and having functional limitations; having access to a fitness facility was inversely associated with inactivity. Among women, inactivity was also associated with being Hispanic, non-Hispanic black, having frequent anxiety/depression or social limitations, needing special equipment, and not receiving physical activity counseling. Among men, inactivity was also associated with severe joint pain. CONCLUSIONS: Although physical activity is a recommended therapy for people with arthritis, levels among adults with arthritis are insufficient, and those with arthritis have worse activity profiles than their peers without arthritis. Efforts to promote physical activity should include expanding access to evidence-based interventions and recreational facilities/programs. The importance of physical activity counseling and associated pain management measures by healthcare providers should be emphasized.