Resumo ObjetivoValidar a versão brasileira do Nordic Musculoskeletal Questionnaire -NMQ (Questionário Nórdico de Sintomas Osteomusculares -QNSO) e apresentar as relações entre morbidade osteomuscular e variáveis demográficas, ocupacionais e relativas a hábitos. Métodos A versão brasileira do instrumento NMQ foi aplicada a uma amostra de 90 empregados em uma instituição bancária estatal, em Brasília, em 1999. Foram realizadas análises descritivas da amostra e de associação entre as variáveis. Os resultados foram comparados a dados relativos à história clínica de cada respondente. Realizou-se análise estatística de comparação entre grupos (Test t) e de correlação entre variáveis (Pearson). Resultados Os resultados mostraram concordância entre o relato de sintomas no NMQ e a história clínica em 86% dos casos. Foram verificadas diferenças na prevalência de sintomas quanto ao gênero, à função exercida e à prática de atividade física. As mulheres apresentaram maior média de severidade de sintomas em quase todas as regiões anatômicas; os gerentes relataram maior severidade de sintomas em região lombar do que escriturários; a prática de atividade física regular esteve associada à menor severidade de sintomas em membros superiores. Conclusões Os resultados mostram um bom índice de validade concorrente para a versão brasileira do NMQ e recomendam sua utilização como medida de morbidade osteomuscular. Entretanto, o instrumento necessita de uma medida de severidade de sintomas e de alterações na diagramação e no conteúdo da escala para torná-la mais compreensível e menos suscetível a um excessivo número de respostas em branco. Abstract ObjectivesTo validate the Portuguese version of the Nordic Musculoskeletal Questionnaire (NMQ), and to evaluate the relationship between musculoskeletal morbidity and demographic, occupational and behavior variables.

SUMMARY Removal of introns from pre-mRNAs via splicing provides a versatile means of genetic regulation that is often disrupted in human diseases. To decipher how splicing occurs in real time, we have directly examined with single-molecule sensitivity the kinetics of intron excision from pre-mRNA in the nucleus of living human cells. By using two different RNA labeling methods, MS2 and λN, we show that beta-globin introns are transcribed and excised in 20-30 s. We further show that replacing the weak polypyrimidine (Py) tract in mouse immunoglobulin μ (IgM) pre-mRNA by a U-rich Py decreases the intron lifetime, thus providing direct evidence that splice site strength influences splicing kinetics. We also found that RNA polymerase II transcribes at elongation rates ranging between 3 and 6 kb min-1, and that transcription can be rate limiting for splicing. These results have important implications for mechanistic understanding of co-transcriptional splicing regulation in the live-cell context.

fAter being released from transcription sites, messenger ribonucleoprotein particles (mRNPs) must reach the nuclear pore complexes in order to be translocated to the cytoplasm. Whether the intranuclear movement of mRNPs results largely from Brownian motion or involves molecular motors remains unknown. Here we have used quantitative photobleaching techniques to monitor the intranuclear mobility of protein components of mRNPs tagged with GFP. The results show that the diffusion coefficients of the poly(A)-binding protein II (PABP2) and the export factor TAP are significantly reduced when these proteins are bound to mRNP complexes, as compared with nonbound proteins. The data further show that the mobility of wild-type PABP2 and TAP, but not of a point mutant variant of PABP2 that fails to bind to RNA, is significantly reduced when cells are ATP depleted or incubated at 22°C. Energy depletion has only minor effects on the intranuclear mobility of a 2,000-kD dextran (which corresponds approximately in size to 40S mRNP particles), suggesting that the reduced mobility of PABP2 and TAP is not caused by a general alteration of the nuclear environment. Taken together, the data suggest that the mobility of mRNPs in the living cell nucleus involves a combination of passive diffusion and ATP-dependent processes.

In the nucleus of higher eukaryotes, maturation of mRNA precursors involves an orderly sequence of transcription-coupled interdependent steps. Transcription is well known to influence splicing, but how splicing may affect transcription remains unclear. Here we show that a splicing mutation that prevents recruitment of spliceosomal snRNPs to nascent transcripts causes co-transcriptional retention of unprocessed RNAs that remain associated with polymerases stalled predominantly at the 3' end of the gene. In contrast, treatment with spliceostatin A, which allows early spliceosome formation but destabilizes subsequent assembly of the catalytic complex, abolishes 3' end pausing of polymerases and induces leakage of unspliced transcripts to the nucleoplasm. Taken together, the data suggest that recruitment of splicing factors and correct assembly of the spliceosome are coupled to transcription termination, and this might ensure a proofreading mechanism that slows down release of unprocessed transcripts from the transcription site.

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