We show here that the radiosensitive Chinese hamster cell mutant (V-C8) of group XRCC11 is defective in the breast cancer susceptibility gene Brca2. The very complex phenotype of V-C8 cells is complemented by a single human chromosome 13 providing the BRCA2 gene, as well as by the murine Brca2 gene. The Brca2 deficiency in V-C8 cells causes hypersensitivity to various DNA-damaging agents with an extreme sensitivity toward interstrand DNA cross-linking agents. Furthermore, V-C8 cells show radioresistant DNA synthesis after ionizing radiation, suggesting that Brca2 deficiency affects cell cycle checkpoint regulation. In addition, V-C8 cells display tremendous chromosomal instability and a high frequency of abnormal centrosomes. The mutation spectrum at the hprt locus showed that the majority of spontaneous mutations in V-C8 cells are deletions, in contrast to wild-type V79 cells. A mechanistic explanation for the genome instability phenotype of Brca2-deficient cells is provided by the observation that the nuclear localization of the central DNA repair protein in homologous recombination, Rad51, is reduced in V-C8 cells.V-C8 is a Chinese hamster cell mutant that represents the XRCC11 complementation group, among X-ray-sensitive rodent cell mutants, as well as a distinguished group among mitomycin C (MMC)-sensitive rodent cell mutants (for a review, see reference 46). This mutant is extremely sensitive to cross-linking agents, but it also shows an increased sensitivity toward many other DNA-damaging agents, such as methyl methanesulfonate (MMS) and UV light (19,48). This suggests that the XRCC11 gene is involved in a wide-ranging cellular response induced by various types of DNA damage. V-C8 cells display radioresistant DNA synthesis (RDS) after ionizing irradiation (36), which is indicative of a defect in DNA damage recognition or cell cycle checkpoint regulation. However, the high level of spontaneous and cross-link-induced chromosomal aberrations manifested by V-C8 cells (19) indicates a possible defect in DNA repair. Indeed, V-C8 cells have an impaired capacity for repair of DNA double-strand breaks (DSBs) after irradiation (36).In mammalian cells, DSBs are repaired via either nonhomologous end joining (NHEJ) or homologous recombination (HR) (reviewed in reference 14). Genetic complementation studies have determined that V-C8 cells are not defective in DNA-PKcs, Ku80, or Xrcc4, key components of NHEJ, nor in Xrcc2 or Xrcc3, proteins involved in HR, and that this mutant represents a separate complementation group, XRCC11 (36,46). When compared to cell lines defective in the above-mentioned proteins, the overall phenotype of V-C8 cells more closely resembles those of the Xrcc2-and Xrcc3-defective hamster cell lines irs1 and irs1SF, respectively (8,12,16). In common with V-C8, irs1 and irs1SF exhibit an extreme sensitivity to cross-linking agents that is not observed in cell lines defective in NHEJ proteins. This favors the hypothesis that the XRCC11 gene defective in V-C8 cells might be involved in HR. A key playe...

O objetivo do trabalho é analisar tendências da pesquisa em Educação Física Escolar no Brasil. Desenvolveu-se revisão sistemática em periódicos nacionais, de 2006 a 2012. A produção dessa área representa apenas 16,20% do total de artigos publicados. Entre os delineamentos, pesquisas bibliográficas e de campo se destacaram. Os estudos de enfoque diagnóstico se sobressaíram. Observa-se ainda uma tendência de crescimento em estudos de intervenção pedagógica, tal como no cenário internacional. Considerando a relevância social da Educação Física Escolar, faz-se necessário fomentar políticas de pesquisa e pós-graduação que atendam às especificidades da área.

RESUMOA adolescência é acompanhada de mudanças cognitivas, emocionais, sociais e biológicas que ampliam as situações de risco ao desenvolvimento de disfunções psicossomáticas. Este estudo aferiu e classificou a composição corporal e a comparou à autopercepção corporal em adolescentes. Alunos do sétimo ao nono ano do ensino fundamental público no Distrito Federal, Brasil, responderam a questionários sóciodemográfico e de percepção corporal. Massa e estatura foram medidas e o Índice de Massa Corporal (IMC) foi calculado para classificação da composição corporal. Dos 977 adolescentes, 79.1% apresentaram IMC eutrófico. Dos 473 meninos, 11.4% apresentaram excesso de peso e 4.7% baixo peso; 23.8% perceberam o corpo como menor do que realmente é e 25.5% tentaram ganhar massa corporal. Das 504 meninas, 11.9% apresentaram excesso de peso e 13.4% baixo peso; 24.1% perceberam o corpo como maior do que realmente é e 32.5% tentaram perder massa corporal. A composição corporal inadequada, prevalente em 20.9% dos adolescentes, pode trazer prejuízos ao crescimento, desenvolvimento e saúde. Estes problemas podem ser agravados pela elevada prevalência de autopercepção corporal distorcida e de atitudes para obter mudanças corporais. Recomenda-se a realização de intervenções educativas sobre composição, percepção e cultura corporal e saúde de forma integrada, com abordagens diferenciadas por sexo. Palavras-chave: imc, imagem corporal, sobrepeso, baixo peso, saúde ABSTRACT Adolescence is accompanied by cognitive, emotional, social and biological changes; situations that increase the risk for development of psychosomatic disorders. This study measured and classified body composition and compared it to body self-perception in adolescents. Students from the seventh to ninth grade in public primary education in Distrito Federal, Brazil, answered socio-demographic and body self-perception questionnaires. Weight and height were measured and body mass index (BMI) was calculated for body composition classification. From the 977 adolescents, 79.1% presented eutrophic BMI. Of the 473 boys, 11.4% were overweight and 4.7% underweight, 23.8% perceived the body as smaller than it really is and 25.5% tried to gain body mass. Of the 504 girls, 11.9% were overweight and 13.4% underweight, 24.1% perceived the body as larger than it really is and 32.5% tried to lose body mass. Inadequate body composition, prevalent in 20.9% of adolescents, may harm growth, development and health. These problems may be aggravated by the high prevalence of distorted body self-perception and attitudes for bodily changes. It is recommended the implementation of educational interventions on body composition, perception and culture and health, with different approaches by gender.

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A pesquisa teve como objetivo analisar atividades de educação física presentes no currículo original da Escola-Parque de Brasília, na década de 1960. Utilizamos como referência teórico-metodológica a história cultural, enfocando o tratamento de fontes primárias, como fotografias, documentos oficiais, entrevistas e publicações da época. As fontes evidenciaram que a educação física se realizava na forma de recreação, esportes, competições, desfiles e aulas, ocupando lugar de destaque na cultura escolar analisada. As atividades de educação física faziam parte de um projeto educacional inovador, cuja concepção pedagógica, currículo ampliado, turno integral e arquitetura especial valorizavam uma educação do corpo.