Carotid plaque regression following 6-month statin therapy assessed by 3T cardiovascular magnetic resonance: comparison with ultrasound intima media thickness

<p>Abstract</p> <p>Background</p> <p>Cardiovascular magnetic resonance (CMR) allows volumetric carotid plaque measurement that has advantage over 2-dimensional ultrasound (US) intima-media thickness (IMT) in evaluating treatment response. We tested the hypothesis that 6-month statin treatment in patients with carotid plaque will lead to plaque regression when measured by 3 Tesla CMR but not by IMT.</p> <p>Methods</p> <p>Twenty-six subjects (67 ± 2 years, 7 females) with known carotid plaque (> 1.1 mm) and coronary or cerebrovascular atherosclerotic disease underwent 3T CMR (T1, T2, proton density and time of flight sequences) and US at baseline and following 6 months of statin therapy (6 had initiation, 7 had increase and 13 had maintenance of statin dosing). CMR plaque volume (PV) was measured in the region 12 mm below and up to 12 mm above carotid flow divider using software. Mean posterior IMT in the same region was measured. Baseline and 6-month CMR PV and US IMT were compared. Change in lipid rich/necrotic core (LR/NC) and calcification plaque components from CMR were related to change in PV.</p> <p>Results</p> <p>Low-density lipoprotein cholesterol decreased (86 ± 6 to 74 ± 4 mg/dL, p = 0.046). CMR PV decreased 5.8 ± 2% (1036 ± 59 to 976 ± 65 mm³, p = 0.018). Mean IMT was unchanged (1.12 ± 0.06 vs. 1.14 ± 0.06 mm, p = NS). Patients with initiation or increase of statins had -8.8 ± 2.8% PV change (p = 0.001) while patients with maintenance of statin dosing had -2.7 ± 3% change in PV (p = NS). There was circumferential heterogeneity in CMR plaque thickness with greatest thickness in the posterior carotid artery, in the region opposite the flow divider. Similarly there was circumferential regional difference in <it>change </it>of plaque thickness with significant plaque regression in the anterior carotid region in region of the flow divider. Change in LR/NC (R = 0.62, p = 0.006) and calcification (R = 0.45, p = 0.03) correlated with PV change.</p> <p>Conclusions</p> <p>Six month statin therapy in patients with carotid plaque led to reduced plaque volume by 3T CMR, but ultrasound posterior IMT did not show any change. The heterogeneous spatial distribution of plaque and regional differences in magnitude of plaque regression may explain the difference in findings and support volumetric measurement of plaque. 3T CMR has potential advantage over ultrasound IMT to assess treatment response in individuals and may allow reduced sample size, duration and cost of clinical trials of plaque regression.</p

Participatory instructional redesign by students and teachers in secondary education: effects on perceptions of instruction

Könings, K. D., Brand-Gruwel, S., & Van Merriënboer, J. J. G. (2011). Participatory instructional redesign by students and teachers in secondary education: effects on perceptions of instruction. Instructional Science, 39(5), 737–762.Students’ perceptions of instruction are important because they direct the learning of students. The fact that teachers have only limited knowledge of these perceptions is likely to threaten the effectiveness of learning, because congruence between interpretations of an instructional intervention is necesarry for its optimal use. This study examines participatory design as a strategy for taking student perceptions into account in instructional re/design. Participatory design meetings of groups of teachers and seven co-designing students in a secondary education setting identified changes to improve the regular education process. The results on changes in student perceptions, perceived-desired discrepancy, and teacher-student disagreement showed some improvement for the co-designers but, unexpectedly, limited or even negative effects for the non-co-designing students. Possible causes are discussed. Participatory design seems to have potential for improving education, but further research is needed

ERGONOMIA E SEGURANÇA EM ATIVIDADES EXTRATIVISTAS NO ESTADO DO ACRE

A ergonomia é a ciência que estuda a adaptação do trabalho ao homem, tendo como objetivo a melhoria das condições de saúde, segurança e bem estar do trabalhador. Apesar de existirem diversos estudos de ergonomia em vários setores, ao que tange atividades extrativistas, ainda são poucas as informações obtidas. Esta pesquisa teve como objetivo analisar e compreender as condições de trabalho, saúde e segurança das atividades na coleta e transporte de castanha e açaí na Reserva Extrativista Cazumbá - Iracema no Estado do Acre, a fim de propor sugestões à referida categoria a partir da análise dos fatores ergonômicos. As variáveis analisadas foram os fatores humanos, ambientais (clima e iluminação), carga física, posturas adotadas e o manuseio de cargas. Foram avaliados ao total 40 trabalhadores. De acordo com os resultados, os trabalhadores tinham idade média de 35 anos, peso médio de 69 kg, baixo índice de analfabetismo (2,3%), de origem predominantemente rural (94,1%), tendo um consumo alto de bebidas alcoólicas (49%) e tabaco (15%). A maioria dos trabalhadores já tiveram acidentes em suas atividades. A exposição ao calor e a iluminância foram considerados elevados e inadequados entre os horários de 12 e 13:30 horas. A carga física foi considerada moderadamente pesada na maioria das operações, destacando-se o transporte de castanha e a coleta do açai, sendo considerados pesados. As posturas mais prejudiciais foram observadas na coleta do açaí e no transporte de castanha. O manuseio de cargas apresentou alto risco de lesão nas atividades de transporte de castanha. Para melhoria das condições de trabalho, saúde, bem estar e segurança, deve haver uma conscientização a fim de diminuir os vícios e fiscalização para que haja o uso devido dos equipamentos de proteção individual. Ainda assim, os trabalhadores devem ser treinados e conscientizados para utilizar medidas adequadas de controle onde os níveis de exposição a iluminância são elevados. Também necessita-se de adoção de tempo de repouso por hora efetiva de trabalho nas atividades de coleta do açaí e transporte de castanha. A fim de evitar danos a coluna do trabalhador, é necessário a adoção de pausas durante as atividades de coleta e transporte de ambas as cadeias analisadas. E com relação ao manuseio de cargas é necessária uma reorganização ergonômica a fim de reduzir o peso manuseado para execução da atividade de transporte de castanha. Palavra - chave: Processo Produtivo, Unidades de Conservação, Condições de Trabalho

A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

Meeting abstrac