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Cyclic AMP (cAMP) is an important second messenger in virtually all animal cell types, including astrocytes. In the brain, it modulates energy metabolism, development and synaptic plasticity. Dopamine receptors are G protein-coupled receptors that affect cAMP production by adenylyl cyclases. They are divided into two subgroups, D1-like receptors linked to Gs proteins stimulating cAMP production and D2-like receptors linked to Gi/o proteins inhibiting cAMP production. In the present study, we investigated the effect of dopamine receptor activation on cAMP dynamics in astrocytes of the mouse olfactory bulb, the brain region with the largest population of dopaminergic neurons. Using the genetically encoded cAMP sensor Flamindo2 we visualized changes in the cytosolic cAMP concentration and showed that dopamine application results in a transient increase in cAMP. This cAMP increase could be mimicked by the D1-like receptor agonist A 68930 and was inhibited by the D1-like receptor antagonist SCH 23390, whereas D2-like receptor ligands had no effect on the astrocytic cAMP concentration. Thus, olfactory bulb astrocytes express D1-like receptors that are linked to cAMP production.

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Introduction: The cyclic nucleotide cyclic adenosine monophosphate (cAMP) is a ubiquitous second messenger, which is known to play an important anti-inflammatory role. Astrocytes in the central nervous system (CNS) can modulate inflammation but little is known about the significance of cAMP in their function. Methods: We investigated cAMP dynamics in mouse olfactory bulb astrocytes in brain slices prepared from healthy and experimental autoimmune encephalomyelitis (EAE) mice. Results: The purinergic receptor ligands adenosine and adenosine triphosphate (ATP) both induced transient increases in cAMP in astrocytes expressing the genetically encoded cAMP sensor Flamindo2. The A2A receptor antagonist ZM241385 inhibited the responses. Similar transient increases in astrocytic cAMP occurred when olfactory receptor neurons were stimulated electrically, resulting in ATP release from the stimulated axons that increased cAMP, again via A2A receptors. Notably, A2A-mediated responses to ATP and adenosine were not different in EAE mice as compared to healthy mice. Discussion: Our results indicate that ATP, synaptically released by afferent axons in the olfactory bulb, is degraded to adenosine that acts on A2A receptors in astrocytes, thereby increasing the cytosolic cAMP concentration. However, this pathway is not altered in the olfactory bulb of EAE mice.

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Ca2+ imaging is the most frequently used technique to study glial cell physiology. While chemical Ca2+ indicators served to visualize and measure changes in glial cell cytosolic Ca2+ concentration for several decades, genetically encoded Ca2+ indicators (GECIs) have become state of the art in recent years. Great improvements have been made since the development of the first GECI and a large number of GECIs with different physical properties exist, rendering it difficult to select the optimal Ca2+ indicator. This review discusses some of the most frequently used GECIs and their suitability for glial cell research.

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PURPOSE: The purpose of this paper is to measure the prevalence, evaluate the trend and identify the factors associated with the non-performance of qualitative urine test (QUT) among pregnant women living in the extreme south of Brazil between 2007 and 2016. DESIGN/METHODOLOGY/APPROACH: All births occurred in the local maternity wards from January 1 to December 31 of 2007, 2010, 2013 and 2016. Mothers were interviewed within 48h after delivery. The outcome was the non-performance of QUT during pregnancy. χ2 test was used to compare proportions and Poisson regression with robust variance adjustment for the multivariate analysis. The effect measure used was the prevalence ratio. FINDINGS: Of the 10,331 new mothers identified, 10,004 (96.8 percent) performed at least one prenatal visit. The prevalence of non-performance of QUT was 3.3 percent (95% CI 2.9-3.7 percent), ranging from 1.5 percent in 2007 to 5.3 percent in 2016 ( p<0.001). The analysis showed that not living with a companion, having under four years of schooling, living with seven or more people in the household, having five or more children, having had one to three prenatal visits and not having been supplemented with ferrous sulfate during pregnancy showed a significantly higher prevalence rate to the non-performance of QUT. ORIGINALITY/VALUE: The rate of non-performance of this test among pregnant women has clearly increased. Mothers at higher risk of unfavorable outcomes in pregnancy were the ones with the highest probability of not performing QUT. Increasing the number of prenatal visits is a high-impact measure toward the performance of this test.

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Abstract Objectives: to measure the prevalence and identify factors associated to the occurrence of cesarean section on demand in the municipality of Rio Grande, RS. Methods: all births that occurred in the two maternities between 01/01 to 12/31/2007, mothers who lived in the municipality were questioned on demographic and maternal reproductive characteristics, family socioeconomic level and health care received during pregnancy and childbirth. The outcome was constituted by cesarean section on demand, in other words, the request was from the parturient. In the analysis, Poisson regression was used with robust adjustment of the variance. The effect measurement used was the prevalence ratios (PR). Results: among the 2,557 parturients included in this study, 51.6% (CI95%:49.6%-53.5%) were submitted to cesarean sections, and 10.7% (CI95%:9.0%-12.4%) were on demand. After the adjustment based on previous hierarchical model, the variables showed significantly the association to the outcomes which were maternal schooling, household income, type of hospitalization (public or private) and being attended by the same physician throughout the prenatal period. Conclusions: the PR obtained show that the probability of occurrence of cesarean section on demand was substantially higher among the mothers who presented the lowest risk of complications during pregnancy and childbirth.

Resumo Objetivos: medir a prevalência e identificar fatores associados a ocorrência de cesarianas a pedido no município de Rio Grande, RS. Métodos: para todos os nascimentos ocorridos nas duas maternidades do município entre 01/01 a 31/12/2007, cujas mães residiam no município, foram investigadas características demográficas e reprodutivas maternas, socioeconômicas da família e assistência recebida durante a gestação e o parto. O desfecho foi constituído pela realização de cesariana a pedido, ou seja, por solicitação da parturiente. Na análise utilizou-se regressão de Poisson com ajuste robusto da variância. A medida de efeito utilizada foi razão de prevalências (RP). Resultados: dentre as 2.557 parturientes incluídas no estudo, 51,6% (IC95%:49,6%-53,5%) foram submetidas à cesariana, sendo 10,7% (IC95%:9,0%-12,4%) a pedido. Após ajuste obedecendo modelo hierárquico prévio, mostraram-se significativamente associadas ao desfecho as variáveis escolaridade materna, renda familiar, tipo de internação (público ou privada) e ter sido atendida pelo mesmo médico durante todo o pré-natal. Conclusões: as RP obtidas mostram que a probabilidade de ocorrência de cesariana a pedido foi substancialmente maior entre mães que apresentam os menores riscos de complicações durante a gravidez e o parto.

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