Sickle Cell Anaemia Prevalence among Newborns in the Brazilian Amazon-Savanna Transition Region
Sickle cell anaemia is one of the most common hemoglobinopathies worldwide and an important public health problem in Brazil. This study evaluated the prevalence of sickle cell anaemia and its traits in newborns from the Amazon-Savanna Transition Region in the state of Maranhão, Brazil. A cross-sectional study was carried out, based on data from neonatal screening tests performed in 2013–2015 in Maranhão. The Hardy-Weinberg theorem was applied to analyse the frequency of expected homozygotes based on HbSS phenotype. A spatial-temporal distribution analysis was performed to delimit the regions with the greatest number of newborn cases with sickle cell anaemia. Of 283,003 newborns, 162 were found to have sickle cell anaemia, while 10,794 had a sickle cell trait, with a prevalence of 0.05% and 3.8%, respectively. The prevalence of expected homozygotes was higher in the North Region and in the state capital of Maranhão. This study may contribute to existing social and public health actions or the creation of new strategies for sickle cell disease in endemic areas in Brazil to improve the quality of life.
Prevalência de hemoglobina S em recém-nascidos de Fortaleza: importância da investigação neonatal The prevalence of hemoglobin S in newborns from Fortaleza, Brazil: The importance of neonatal research
OBJETIVOS: avaliar a prevalencia de hemoglobina S (HbS, tracos falciformes) em recem-nascidos, por meio de investigacao clinico-laboratorial. METODOS: foi elaborado protocolo que estabelece a coleta de 10 ml de sangue de segmento de cordao umbilical, apos ser ligado e seccionado pelo obstetra em seguida ao parto, sendo as amostras introduzidas em um tubo contendo EDTA a 5% e submetidas a estudo cromatografico liquido de alta resolucao (high-performance liquid chromatography). Preenchia-se tambem protocolo clinico mediante entrevista com a puerpera, analisava-se o seu prontuario e efetuava-se o exame fisico do recem-nascido. As variaveis analisadas foram peso do recem-nascido, sexo, Apgar no primeiro minuto e cor da mae. A analise estatistica foi baseada no programa Epi-Info versao 6.0, utilizando-se o teste t de Student, considerando-se o nivel de significância de p<0,05. RESULTADOS: no periodo de agosto de 2001 a setembro de 2002, foram analisadas 389 amostras de sangue de cordao umbilical e identificada a presenca de HbS em 16 recem-nascidos (4,1%), 15 dos quais compativeis com tracos falcemicos (HbAS) e um com a hipotese diagnostica de anemia falciforme (HbSS). Observou-se maior prevalencia de hemoglobinopatia no sexo masculino. Nao houve diferenca significante entre os recem-nascidos com ou sem HbS para medias de peso e escores de Apgar, assim como para cor de pele das maes (brancas, pardas e negras). CONCLUSAO: recomenda-se triagem de hemoglobinopatias em recem-nascidos, tendo em vista a possibilidade da ocorrencia de 25% da anemia falciforme nos filhos de casais com ambos os conjuges apresentando tracos falcemicos. Diante disso, sugere-se a implantacao de programas com esses objetivos e incorporacao as rotinas hospitalares.
Graphs of polyhedra; polyhedra as graphs
Relations between graph theory and polyhedra are presented in two contexts. In the first, the symbiotic dependence between 3-connected planar graphs and convex polyhedra is described in detail. In the second, a theory of nonconvex polyhedra is based on a graph-theoretic foundation. This approach eliminates the vagueness and inconsistency that pervade much of the literature dealing with polyhedra more general than the convex ones.