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Biology subjects

Marinho, C. R. F.

Publications and source records attributed to Marinho, C. R. F..

3 recordsLinked to original sources

Critical contribution of endothelial protein C receptor in experimental malaria-associated acute respiratory distress syndrome

The severity of Plasmodium falciparum malaria is associated with parasite cytoadherence, but there is limited knowledge about the effect of parasite cytoadherence in malaria-associated acute respiratory distress syndrome (ARDS). Our objective was to evaluate the cytoadherence of infected red blood cells (iRBCs) in a murine model of ARDS and to appraise a potential function of endothelial protein C receptor (EPCR) in ARDS pathogenesis. DBA/2 mice infected with P. berghei ANKA were classified as ARDS- or hyperparasitemia (HP)-developing mice according to respiratory parameters and parasitemia. Lungs, blood and bronchoalveolar lavage were collected for gene expression or protein analyses. Primary cultures of microvascular lung endothelial cells from DBA/2 mice were analyzed for iRBC interactions. Lungs from ARDS-developing mice showed evidence of iRBC accumulation along with an increase in EPCR and TNF concentrations. Furthermore, TNF increased iRBC adherence in vitro. Dexamethasone-treated infected mice showed low levels of TNF and EPCR mRNA expression and, finally, decreased vascular permeability, thus protecting mice from ARDS. In conclusion, we identified that increased iRBC cytoadherence in the lungs underlies malaria-associated ARDS in DBA/2-infected mice and that inflammation increased cytoadherence capacity, suggesting a participation of EPCR and a conceivable target for drug development.

pathology

Malaria during pregnancy and newborns outcome in an unstable transmission area in Brazil: a population-based record linkage study

BackgroundMalaria during pregnancy is one of the major causes of mortality in tropical regions, causing maternal anemia, intrauterine growth retardation, preterm birth, and low birth weight (LBW). The integration of the information systems is crucial to assess the dimension of gestational malaria in a wide and useful way, to improve decision making and maternal-child health.\n\nMethods and FindingsAn observational population-based study acquired information retrospectively from all live births that occurred between 2006 and 2014 in Cruzeiro do Sul (Acre, Brazil). Social and clinical data of the mother and newborn was extracted from the Information System of Live Births. Malaria episodes information was obtained from the Brazilian Epidemiological Surveillance Information System Malaria. A deterministic record linkage was performed to assess malaria impact on pregnancy. The studied population presented a malaria incidence of 8.9%, of which 63.9% infected by Plasmodium (P.) vivax. Reduction of newborns birth weight at term (small for gestational age (SGA) and LBW) has been found associated with P. vivax infection during pregnancy (SGA - OR 1.24, 95% CI 1.02-1.52, p=0.035; term LBW - OR 1.39, 95% CI 1.03-1.88, p=0.033). Additionally, P. falciparum infection during pregnancy has been found to be associated with preterm births (OR 1.54, 95% CI 1.09-2.18, p=0.016), which is related with late preterm births (OR 1.59, 95% CI 1.11-2.27, p=0.011).\n\nConclusionsDespite the decrease of malaria cases during the evaluated period, we present evidence of the deleterious effects of gestational malaria in a low transmission area in the Amazonian region. Regardless of Plasmodium species, malaria during pregnancy poses a risk for newborns birth weight reduction, highlighting the impact that P. vivax has on the fetus.\n\nFundingSao Paulo Research Foundation - FAPESP/Brazil.

epidemiology

Plasmodium falciparum infection during pregnancy impairs fetal head growth: prospective and populational-based retrospective studies

BackgroundMalaria in pregnancy is associated with adverse effects on the fetus and newborns. However, the outcome on a newborns head circumference (HC) is still unclear. Here, we show the relation of malaria during pregnancy with fetal head growth.\n\nMethodsClinical and anthropometric data were collected from babies in two cohort studies of malaria-infected and non-infected pregnant women, in the Brazilian Amazon. One enrolled prospectively (PCS, Jan. 2013 to April 2015) through volunteer sampling, and followed until delivery, 600 malaria-infected and non-infected pregnant women. The other assembled retrospectively (RCS, Jan. 2012 to Dec. 2013) clinical and malaria data from 4697 pregnant women selected through population-based sampling. The effects of malaria during pregnancy in the newborns were assessed using a multivariate logistic regression. According with World Health Organization guidelines babies were classified in small head (HC < 1 SD below the median) and microcephaly (HC < 2 SD below the median) using international HC standards.\n\nResultsAnalysis of 251 (PCS) and 232 (RCS) malaria-infected, and 158 (PCS) and 3650 (RCS) non-infected women with clinical data and anthropometric measures of their babies was performed. Among the newborns, 70 (17.1%) in the PCS and 934 (24.1%) in the RCS presented with a small head (SH). Of these, 15 (3.7%) and 161 (4.2%), respectively, showed microcephaly (MC). The prevalence of newborns with a SH (30.7% in PCS and 36.6% in RCS) and MC (8.1% in PCS and 7.3% in RCS) was higher among babies born from women infected with Plasmodium falciparum during pregnancy. Multivariate logistic regression analyses revealed that P. falciparum infection during pregnancy represents a significant increased odds for the occurrence of a SH in newborns (PCS: OR 3.15, 95% CI 1.52-6.53, p=0.002; RCS: OR 1.91, 95% CI 1.21-3.04, p=0.006). Similarly, there is an increased odds of MC in babies born from mothers that were P. falciparum-infected (PCS: OR 5.09, 95% CI 1.12-23.17, p=0.035). Moreover, characterization of placental pathology corroborates the association analysis, particularly through the occurrence of more syncytial nuclear aggregates and inflammatory infiltrates in placentas from babies with the reduced head circumference.\n\nConclusionsThis work indicates that falciparum-malaria during pregnancy presents an increased likelihood of occurring reduction of head circumference in newborns, which is associated with placental malaria.\n\nTrial Registrationregistered as RBR-3yrqfq in the Brazilian Clinical Trials Registry

epidemiology