Dendritic spine loss and synaptic alterations in Alzheimer's disease

Dendritic spines are tiny protrusions along dendrites, which constitute major postsynaptic sites for excitatory synaptic transmission. These spines are highly motile and can undergo remodeling even in the adult nervous system. Spine remodeling and the formation of new synapses are activity-dependent processes that provide a basis for memory formation. A loss or alteration of these structures has been described in patients with neurodegenerative disorders such as Alzheimer's disease (AD), and in mouse models for these disorders. Such alteration is thought to be responsible for cognitive deficits long before or even in the absence of neuronal loss, but the underlying mechanisms are poorly understood. This review will describe recent findings and discoveries on the loss or alteration of dendritic spines induced by the amyloid beta (Abeta) peptide in the context of AD

Assessing the impact of race, social factors and air pollution on birth outcomes: a population-based study

Abstract Background Both air pollution exposure and socioeconomic status (SES) are important indicators of children’s health. Using highly resolved modeled predictive surfaces, we examine the joint effects of air pollution exposure and measures of SES in a population level analysis of pregnancy outcomes in North Carolina (NC). Methods Daily measurements of particulate matter <2.5 μm in aerodynamic diameter (PM2.5) and ozone (O3) were calculated through a spatial hierarchical Bayesian model which produces census-tract level point predictions. Using multilevel models and NC birth data from 2002–2006, we examine the association between pregnancy averaged PM2.5 and O3, individual and area-based SES indicators, and birth outcomes. Results Maternal race and education, and neighborhood household income were associated with adverse birth outcomes. Predicted concentrations of PM2.5 and O3 were also associated with an additional effect on reductions in birth weight and increased risks of being born low birth weight and small for gestational age. Conclusions This paper builds on and complements previous work on the relationship between pregnancy outcomes and air pollution exposure by using 1) highly resolved air pollution exposure data; 2) a five-year population level sample of pregnancies; and 3) including personal and areal level measures of social determinants of pregnancy outcomes. Results show a stable and negative association between air pollution exposure and adverse birth outcomes. Additionally, the more socially disadvantaged populations are at a greater risk; controlling for both SES and environmental stressors provides a better understanding of the contributing factors to poor children’s health outcomes.http://deepblue.lib.umich.edu/bitstream/2027.42/109504/1/12940_2013_Article_720.pd

Proximity to roadways and pregnancy outcomes

Adverse birth outcomes are associated with exposure to air pollution during pregnancy. Road proximity is a simple, widely available metric for capturing local variation in exposure to traffic-related air pollution. We characterized maternal exposure to traffic-related air pollution during pregnancy using residential proximity to major roadways among 2004–2008 singleton births in NC. Controlling for maternal race, age, education, nativity, marital status, and tobacco use, and season of birth, parity, infant sex, and Census tract-level urbanization and income, we evaluated the association between road proximity and pregnancy outcomes using generalized linear mixed models with a random intercept for each Census tract. Birth weight, birth weight percentile for gestational age, gestational hypertension, and small-for-gestational age were not associated with road proximity; however, women residing within 250 m of a major roadway were at 3–5% increased odds of low birth weight, preterm birth, and late preterm birth compared with women residing beyond 250 m (P<0.05). Our analyses demonstrate an association between proximity to major roadways and pregnancy outcomes using a large sample. Road proximity may represent a relatively straightforward method for assessing maternal risk from exposure to traffic-related air pollution, with results offering guidance for studies that can more accurately characterize air pollution exposures

Pulmonary exposure to carbon black by inhalation or instillation in pregnant mice: Effects on liver DNA strand breaks in dams and offspring

Effects of maternal pulmonary exposure to carbon black (Printex 90) on gestation, lactation and DNA strand breaks were evaluated. Time-mated C57BL/6BomTac mice were exposed by inhalation to 42 mg/m(3) Printex 90 for 1 h/day on gestation days (GD) 8-18, or by four intratracheal instillations on GD 7, 10, 15 and 18, with total doses of 11, 54 and 268 (μg/animal. Dams were monitored until weaning and some offspring until adolescence. Inflammation was assessed in maternal bronchoalveolar lavage (BAL) 3-5 days after exposure, and at weaning. Levels of DNA strand breaks were assessed in maternal BAL cells and liver, and in offspring liver. Persistent lung inflammation was observed in exposed mothers. Inhalation exposure induced more DNA strand breaks in the liver of mothers and their offspring, whereas intratracheal instillation did not. Neither inhalation nor instillation affected gestation and lactation. Maternal inhalation exposure to Printex 90-induced liver DNA damage in the mothers and the in utero exposed offspring