PurposeMaternal and Child Health and Nutrition in Acre, Brazil (MINA-Brazil) is a longitudinal, prospective population-based birth cohort, set-up to understand the effects of early environmental exposures and maternal lifestyle choices on growth and development of the Amazonian children.ParticipantsMother–baby pairs (n=1246) were enrolled at delivery from July 2015 to June 2016 in Cruzeiro do Sul, Acre, Brazil. Mothers of 43.7% of the cohort were recruited in the study during pregnancy from February 2015 to January 2016. Study visits took place during pregnancy, delivery, at 1 month, 6 months, 1 year and 2 years after delivery. In addition to clinical and epidemiological data, samples collected by the MINA-Brazil study include plasma, serum and extracted DNA from blood and faeces, which are stored in a biobank.Findings to dateKey baseline reports found a high prevalence of gestational night blindness (11.5%; 95% CI 9.97% to 13.25%) and maternal anaemia (39.4%; 95% CI 36.84% to 41.95%) at delivery. Antenatal malaria episodes (74.6% ofPlasmodium vivax) were diagnosed in 8.0% of the women and were associated with an average reduction in birth weight z-scores of 0.35 (95% CI 0.14 to 0.57) and in birth length z-scores of 0.31 (95% CI 0.08 to 0.54), compared with malaria-free pregnancies. At 2-year follow-up, data collection strategies combined telephone calls, WhatsApp, social media community and home visits to minimise losses of follow-up (retention rate of 79.5%).Future plansA 5-year follow-up visit is planned in 2021 with similar interviews and biospecimens collection. The findings from this prospective cohort will provide novel insights into the roles of prenatal and postnatal factors in determining early childhood development in an Amazonian population.

BackgroundDifferent studies have shown the advantages of abstinence from cigarette smoking during pregnancy to promote full fetal development. Given that pregnant women do not always abstain from smoking, this study aimed to analyze the effect of different intensities of smoking on birth weight of the newborn.MethodsA cross-sectional study was adopted to explore smoking in a population of pregnant women from a medium-sized city in São Paulo state, Brazil, who gave birth between January and June of 2012. Data were collected from maternal and pediatric medical files and, where data were absent, they were collected by interview during hospitalization for delivery. For data analysis, the effect of potential confounding variables on newborn birth weight was estimated using a gamma response model. The effect of the identified confounding variables was also estimated by means of a gamma response regression model.ResultsThe prevalence of smoking during pregnancy was 13.4% in the study population. In full-term infants, birth weight decreased as the category of cigarette number per day increased, with a significant weight reduction as of the category 6 to 10 cigarettes per day. Compared with infants born to non smoking mothers, mean birth weight was 320 g lower in infants whose mothers smoked 6 to 10 cigarettes per day and 435 g lower in infants whose mothers smoked 11 to 40 cigarettes per day during pregnancy.ConclusionsBased on the study results and the principle of harm reduction, if a pregnant woman is unable to quit smoking, she should be encouraged to reduce consumption to less than six cigarettes per day.

We measured the prevalence of malaria in pregnancy and estimated its impact on birth weight and length and maternal hemoglobin in 1,180 women from Juruá Valley, the main malaria hotspot in Brazil. Antenatal malaria episodes, 74.6% of them due to , were microscopically diagnosed in 8.0% of the women and were associated with an average reduction in birth weight-scores of 0.35 (95% confidence interval [CI] = 0.14-0.57) and in birth length -scores of 0.31 (95% CI = 0.08-0.54), compared with malaria-free pregnancies. Affected mothers had a mean decrease in hemoglobin concentration at delivery of 0.33 g/100 mL (95% CI = 0.05-0.62 g/100 mL); 51.6% were anemic. The timing and frequency of antenatal infections influenced pregnancy outcomes and first- or second-trimester infections were not associated with decreased birth weight and length and maternal hemoglobin at delivery. Although repeated antenatal vivax infections were associated with poorer birth outcomes, even a single vivax malaria episode was associated with a significant reduction in birth weight and length and maternal hemoglobin. Overall, 7.5% women had the parasite's DNA found in peripheral blood at delivery. Most (83.1%) of these 89 perinatal infections were due to and only 7.9% of them progressed to symptomatic disease after delivery. and DNA was found in 0.6% and 0.3% of 637 cord blood samples examined, respectively, but only one newborn developed clinical neonatal malaria. Our results further challenge the notion that vivax malaria is relatively benign during pregnancy and call for better strategies for its prevention.

BackgroundThe knowledge and practices of health professionals have a recognized role in behaviors related to the health of their patients. During pregnancy, this influence can be even stronger because there is frequent contact between women and doctors/nurses at periodic antenatal visits. When trained, supported and motivated, these professionals can act as health promoters. This study aimed to evaluate the effect of a focused educational intervention on improving the knowledge and practices of health professionals concerning diet and physical activity during pregnancy.MethodsA controlled, non-randomized study was performed to assess the effects of an educational intervention on the knowledge and practices of nurses and doctors who provide primary care to pregnant women. The intervention group, doctors and nurses (n = 22) from the family health units in a medium-sized city of São Paulo State, Brazil, received 16 h of training comprising an introductory course and three workshops, whereas the control group, doctors and nurses (n = 20) from traditional basic health units in Botucatu, did not. The professionals’ knowledge was assessed at two time points, 1 month prior to and 1 year after the beginning of the intervention, using an ad hoc self-report questionnaire. The increases in the knowledge scores for walking and healthy eating of the intervention and control groups were calculated and compared using Student’s t-test. To analyze the professionals’ practice, women in the second trimester of pregnancy were asked whether they received guidance on healthy eating and leisure-time walking; 140 of these women were cared for by professionals in the intervention group, and 141 were cared for by professionals in the control group. The percentage of pregnant women in each group that received guidance was compared using the chi-square test and the Prevalence Ratio (PR), and the corresponding 95 % confidence intervals (CI) were calculated.ResultsThe intervention improved the professionals’ knowledge regarding leisure-time walking (92 % increase in the score, p < 0.001). The women who were cared for by the intervention group were more likely to receive guidance regarding leisure-time walking (PR = 2.65; 95 % CI = 1.82-3.83) and healthy eating (PR = 1.76; 95 % CI = 1.34-2.31) when compared to the control group.ConclusionIt is possible to improve the knowledge and practices of health professionals through the proposed intervention aimed at primary health care teams providing antenatal care.

Recebido em 26/10/99; aceito em 23/3/00 LOW COST IN SITU TECHNIQUES IN ELECTROCHEMISTRY: THE QUARTZ CRYSTAL MICROBALANCE. Among in situ techniques, the electrochemical quartz crystal microbalance (EQCM) is a powerful tool for the study of electrochemical reactions that produce mass changes in the electrode/solution interface. This review present some systems in which the EQCM combined with classical electrochemical techniques, gives relevant information for understanding the charge transport process at a molecular level. The aim of this review is to do a brief description of experimental arrangements, with emphasis on some special cares that must be considered by the users. Secondly, some chosen electrochemical systems where the technique was successfully applied are discussed. Finally, a brief analysis of electroacoustic impedance experiments was done in order to show when the Sauerbrey equation can be used.Keywords: EQCM; in situ technique in electrochemistry; electroacoustic impedance. REVISÃO INTRODUÇÃOA eletroquímica estuda fundamentalmente sistemas interfaciais e volumétricos (inserção). Nesses sistemas é de importância capital o conhecimento dos fluxos de carga e massa através da interface eletrodo/solução no entendimento molecular da relação entre estrutura e natureza físico-química das espécies que participam da reação e o fenômeno eletroquími-co em si; ou seja, como estes parâmetros afetam a transferên-cia de carga. Incluída no grupo das técnicas in situ, a microbalança eletroquímica a cristal de quartzo (MECQ) tem demonstrado ser uma ferramenta poderosa no estudo de reações eletroquímicas que produzem modificações na interface eletrodo/eletrólito em uma magnitude suficiente para ser detectada pela técnica e se destacado como uma técnica de baixo custo relativo quando comparada a outras utilizadas em eletroquímica. O objetivo deste artigo é descrever brevemente os procedimentos experimentais, com ênfase em alguns cuidados que o usuário deve ter quando da utilização da téc-nica, assim como mostrar alguns sistemas que utilizam a MECQ obtendo informações fundamentais ao entendimento do processo redox. Com esses exemplos pretende-se ilustrar, de forma crítica, a potencialidade da MECQ, e discutir os cuidados na interpretação dos resultados, além das limitações da técnica. A literatura sobre MECQ é extensa e já foram escritos vários capítulos de livros e artigos de revisão [1][2][3][4][5] .Nos primeiros trabalhos, a microbalança a cristal de quartzo (MCQ) foi utilizada ex situ para medir massas de metais eletrodepositados sobre eletrodos 6,7 . Posteriormente, os méto-dos experimentais requeridos para a utilização da MCQ como sensor de massa in situ para estudo de filmes finos sobre eletrodos foram desenvolvidos independentemente por vários grupos [8][9][10][11][12] . Uma vez que a MCQ começou a ser utilizada in situ em sistemas eletroquímicos, passou a ser denominada MECQ em lugar de MCQ. Nos últimos anos, a MECQ começou a ser utilizada de maneira mais sofisticada, empregando além das medidas de variação de...