The impact of perinatal and socioeconomic factors on mental health problems of children from a poor Brazilian city: a longitudinal study

Low birth weight and preterm birth, and social disadvantage may negatively affect mental health of children, but findings have been inconsistent. To assess the influence of perinatal and social factors on mental health problems in children aged 7-9 years. A random sample of 805 births in So Luis, Brazil was studied in 1997/1998 and again in 2005/2006. Perinatal, socioeconomic and demographic variables were assessed within 24 h after delivery. The Strengths and Difficulties Questionnaire (SDQ) was used to assess mental health problems in the children. Simple and multiple Poisson regressions were used for statistical analysis. The overall prevalence of mental health problems in the total sample was 47.7%. The prevalences of emotional and conduct problems were 58.2 and 48.8%, respectively. Only paternal age (< 20 years) was associated with mental health problems as measured by the full SDQ scale (prevalence ratio PR = 1.27). Children born to single mothers (PR = 1.31) and those with birth weight from 1,500 to 2,499 g (PR = 1.18) and from 2,500 to 2,999 g (PR = 1.17) had a higher risk of emotional problems, but those from low income families had a lower risk (PR = 0.80). Children with a father of less than 20 years had a higher risk of having problems with their peers (PR = 1.75). A maternal education of 9 years or over was inversely associated with peer (PR = 0.70) and conduct problems (PR = 0.73). Girls had a lower risk of conduct (PR = 0.77) and hyperactivity problems (PR = 0.68). A maternal education of 4 years or less increased the risk of hyperactivity (PR = 1.48). Socioeconomic and demographic conditions were better predictors of mental health problems in children than birth weight or preterm birth. However, since most effect sizes were small most mental health problems were, unexplained by the variables in the study.

Recognition by toll-like receptor 2 induces antigen-presenting cell activation and Th1 programming during infection by Neospora caninum

Neospora caninum is an apicomplexan parasite responsible for major economic losses due to abortions in cattle. Toll-like receptors (TLRs) sense specific microbial products and direct downstream signaling pathways in immune cells, linking innate, and adaptive immunity. Here, we analyze the role of TLR2 on innate and adaptive immune responses during N. caninum infection. Inflammatory peritoneal macrophages and bone marrow-derived dendritic cells exposed to N. caninum-soluble antigens presented an upregulated expression of TLR2. Increased receptor expression was correlated to TLR2/MyD88-dependent antigen-presenting cell maturation and pro-inflammatory cytokine production after stimulation by antigens. Impaired innate responses observed after infection of mice genetically deficient for TLR2((-/-)) was followed by downregulation of adaptive T helper 1 (Th1) immunity, represented by diminished parasite-specific CD4(+) and CD8(+) T-cell proliferation, IFN-gamma:interleukin (IL)-10 ratio, and IgG subclass synthesis. In parallel, TLR2(-/-) mice presented higher parasite burden than wild-type (WT) mice at acute and chronic stages of infection. These results show that initial recognition of N. caninum by TLR2 participates in the generation of effector immune responses against N. caninum and imply that the receptor may be a target for future prophylactic strategies against neosporosis. Immunology and Cell Biology (2010) 88, 825-833; doi:10.1038/icb.2010.52; published online 20 April 2010