Prevalência de anticorpos IgG antiparvovírus B19 em gestantes durante o atendimento pré-natal e casos de hidropisia fetal não imune atribuídos ao parvovírus B19, na Cidade do Rio de Janeiro Anti-parvovirus B19 IgG antibody prevalence in pregnant women during antenatal follow-up and cases of non-immune hydropsis fetalis due to parvovirus B19, in the City of Rio de Janeiro

Com o objetivo de medir a prevalência de anticorpos IgG contra o parvovírus B19 em gestantes com até 24 semanas de idade gestacional e detectar a ocorrência de casos de hidropisia fetal não-imune atribuídos a esse vírus, coletamos 249 amostras de soro em uma maternidade de referência na cidade do Rio de Janeiro, entre junho de 2003 e março de 2005. As gestantes foram acompanhadas até o termo da gestação, sendo detectados 17 casos de hidropisia fetal. Quatro casos foram atribuídos ao parvovírus B19 e dois destes ocorreram em gestantes residentes na zona oeste da cidade, em fevereiro de 2005. Resultados positivos para anticorpos IgG antiparvovírus B19 foram encontrados em 172 (71,6%) gestantes (IC 95% 65,5-77,7%), sendo esta prevalência de anticorpos comparável à encontrada em outras cidades brasileiras. A única variável associada com aquisição prévia de anticorpos IgG foi número de gestações anteriores maior que um(p= 0,02, IC 95% 0,36-0,94).<br>With the aim of measuring the prevalence of anti-parvovirus B19 IgG antibodies during pregnancy up to 24 weeks of gestation and detecting cases of nonimmune hydrops fetalis, 249 sera from pregnant women attending a reference hospital in Rio de Janeiro city, from June 2003 to November 2004 were collected. They were followed-up until the end of pregnancy, with 17 cases of fetal hydrops detected. Four cases were caused by parvovirus B19 and two of them occurred in pregnant women living in the western zone of the city, during February 2005. Anti-parvovirus B19 IgG antibodies were found in 172 (71.6%) pregnant women (CI 95% 65.5%-77.7%); this antibody prevalence is similar to results found for others Brazilian cities. The only variable associated with previous acquisition of IgG antibodies to parvovirus B19 was number of pregnancies greater than one (p= 0.02, CI 95% 0.36-0.94)

The Place of the History of Chemistry in the Teaching and Learning of Chemistry

To those of us who are sold on history it may seem non-controversial to suggest that the learning and teaching of chemistry should give cognisance to the historical development of the subject. However, this suggestion is proving controversial amongst some in the chemistry profession. For example, in the October 2010 edition of Chemistry in Australia Rami Ibo takes issue with the emphasis on the history of science in the HSC chemistry curriculum (Year 12) in New South Wales. He studied chemistry, physics and biology for his HSC in NSW and concluded that, because the primary focus of these three sciences was History of Science, “There was hardly any content that challenged our minds, and calculations barely involved plugging in numbers into an equation…..We were required to recall Antoine Lavoisier’s experiments that led to the theories of acids and bases… while my friends in Lebanon were studying ideal gas laws, chemical kinetics, acids and bases, organic chemistry, soaps and detergents, medicinal chemistry and new materials” (Ibo 2010). What does the literature have to say in response to such arguments? Does the presence of the history of chemistry in a curriculum necessarily reduce important content and problem solving skills? A study of the literature suggests at least three reasons for persisting with aspects of the history of chemistry in the learning and teaching of chemistry. 1. The fact that student conceptions sometimes recapitulate early ideas found in the history of chemistry is seen as offering teachers a means of a deeper understanding of student ideas with the potential for more positive learning outcomes. 2. Conceptual clarity is more easily achieved within an historical context. Often conceptual usefulness is pursued at the expense of conceptual depth (de Berg 2008a). 3. The history of chemistry directly gives us some idea of the epistemological status of chemistry within science and knowledge in general and therefore gives a student access to aspects of the Nature of Science. This review chapter also examines different ways the history of chemistry has been incorporated into chemistry curricula and looks at the purported advantages, disadvantages, and limitations of such attempts. Some directions for future research in this area are included in the chapter

Erythrovirus B19 infection in acquired immunodeficiency syndrome: screening by histopathology, immunohistochemistry, and in situ hybridization

Erythrovirus B19 infects erythrocytic progenitors, transiently interrupting erythropoiesis. In AIDS patients it causes chronic anemia amenable to treatment. We looked for evidences of B19 infection in stored bone marrow material from patients with acquired immunodeficiency syndrome. Histological sections were made from stored paraffin blocks from 33 autopsies (39 blocks) and 35 biopsies (45 blocks, 30 patients) performed from 1988 to 2002. They were examined after hematoxylin-eosin (HE) staining, immunohistochemical (IHC), and in situ hybridization. HE revealed intra-nuclear inclusion bodies ("lantern cells") suggesting B19 infection in 19 sections corresponding to 19 of 63 patients examined with this test. Seven of 78 sections subjected to immunohistochemistry were positive, corresponding to 7 of 58 patients examined with this test. Fourteen sections corresponding to 13 of the 20 HE and/or IHC positive patients were subjected to in situ hybridization, with six positives results. Among the 13 patients subjected to the three techniques, only one gave unequivocal positive results in all and was considered a true positive. The frequency of B19 infection (1/63 patients) in the material examined can be deemed low