BackgroundMacrophages have heterogeneous phenotypes and complex functions within both innate and adaptive immune responses. To date, most experimental studies have been performed on macrophages derived from bone marrow, spleen and peritoneum. However, differences among macrophages from these particular sources remain unclear. In this study, the features of murine macrophages from bone marrow, spleen and peritoneum were compared.ResultsWe found that peritoneal macrophages (PMs) appear to be more mature than bone marrow derived macrophages (BMs) and splenic macrophages (SPMs) based on their morphology and surface molecular characteristics. BMs showed the strongest capacity for both proliferation and phagocytosis among the three populations of macrophage. Under resting conditions, SPMs maintained high levels of pro-inflammatory cytokines expression (IL-6, IL-12 and TNF-α), whereas BMs produced high levels of suppressive cytokines (IL-10 and TGF-β). However, SPMs activated with LPS not only maintained higher levels of (IL-6, IL-12 and TNF-α) than BMs or PMs, but also maintained higher levels of IL-10 and TGF-β.ConclusionsOur results show that BMs, SPMs and PMs are distinct populations with different biological functions, providing clues to guide their further experimental or therapeutic use.

Background Bisphenol A (BPA) is a ubiquitous endocrine disrupting compound. Several experimental and epidemiological studies suggest that gestational BPA exposure can lead to neurodevelopmental and behavioral problems in early-life, but results have been inconsistent. We previously reported that prenatal BPA exposure may affect child behavior and differently among boys and girls at ages 3-5 years. Objectives We investigated the association of prenatal and early childhood BPA exposure with behavioral outcomes in 7-9 year old minority children and hypothesized that we would observe the same sex-specific pattern observed at earlier ages. Methods African-American and Dominican women enrolled in an inner-city prospective cohort study and their children were followed from mother’s pregnancy through children’s age 7-9 years. Women during the third trimester of pregnancy and children at ages 3 and 5 years provided spot urine samples. BPA exposure was categorized by tertiles of BPA urinary concentrations. The Child Behavioral Checklist (CBCL) was administered at ages 7 and 9 to assess multiple child behavior domains. Associations between behavior and prenatal (maternal) BPA concentrations and behavior and postnatal (child) BPA concentration were assessed via Poisson regression in models stratified by sex. These models accounted for potential confounders including prenatal or postnatal urinary BPA concentrations, child age at CBCL assessment, ethnicity, gestational age, maternal intelligence, maternal education and demoralization, quality of child’s home environment, prenatal environmental tobacco smoke exposure, and prenatal mono-n-butyl phthalate concentration. Results The direction of the associations differed between boys and girls. Among boys (n=115), high prenatal BPA concentration (upper tertile vs. lower two tertiles) was associated with increased internalizing (β=0.41, p<0.0001) and externalizing composite scores (β=0.40, p<0.0001) and with their corresponding individual syndrome scales. There was a general decrease in scores among girls that was significant for the internalizing composite score (β= −0.17, p=0.04) (n=135). After accounting for possible selection bias, the results remained consistent for boys. Conversely, high postnatal BPA concentration was associated with increased behaviors on both the internalizing composite (β=0.30, p=0.0002) and externalizing composite scores (β=0.33, p<0.0001) and individual subscores in girls but fewer symptoms in boys. These results remained significant in girls after accounting for selection bias. Conclusion These results suggest BPA exposure may affect childhood behavioral outcomes in a sex-specific manner and differently depending on timing of exposure.

High-nitrogen loadings of rivers and aquifers systems are a major concern because of potential effects on human health and water quality impacts such as eutrophication of lakes and coastal zones. This nitrogen enrichment is commonly attributed to anthropogenic sources such as sewage and agricultural and industrial wastes. The aims of this study were to delineate spatial distribution of groundwater ammonium in the coastal aquifer system in Pearl River Delta (PRD), China and to identify the origin of the abnormally high ammonium. A total of 40 boreholes were drilled to collect core samples of the aquitard and groundwater samples in the basal aquifer. The core samples were used for extraction of pore water for centrifugation and bulk chemical analyses in laboratory. Unlike previous studies which focused mainly on the aquifer, this study treated the aquifer-aquitard system as a hydrogeochemical continuum. The results show that the aquifer-aquitard system contains an exceptionally large total ammonium mass. Ammonium occurred at concentrations up to 390 mg/L in the basal sand Pleistocene aquifer 20-50 m deep, the largest concentration reported for groundwater globally. This ammonium was natural, areally extensive (1600 km(2)) and originated in the overlying Holocene-Pleistocene aquitard and entered the aquifer by groundwater transport and diffusion. Total ammonium in the aquifer (190 × 10(6) kg) was exceeded by total ammonium in the aquitard (8600 × 10(6) kg) by a factor of 45. Much organic nitrogen remained in the aquitard available for conversion to ammonium. This natural ammonium in the aquifer was slowly transported into the PRD river channels and the estuary of the South China Sea. The rate of this contribution will likely be greatly increased by sand dredging in the river channels and estuary. Although the ammonium in PRD groundwater occurred in the largest concentrations and mass reported globally, the literature shows no reports of other delta aquitards having been examined for ammonium occurrence and therefore abundant ammonium formed in aquitards rich in organic matter may not be uncommon and this "geologic" source of ammonium may present a large and hitherto unappreciated source of nitrogen discharging to surface waters.