Background Total IgE is a therapeutic target in patients with allergic diseases. DNA methylation in white blood cells (WBCs) was associated with total IgE levels in an epigenome-wide association ...study of white subjects. Whether DNA methylation of eosinophils explains these findings is insufficiently understood. Methods We tested for association between genome-wide DNA methylation in WBCs and total IgE levels in 2 studies of Hispanic children: the Puerto Rico Genetics of Asthma and Lifestyle Study (PR-GOAL; n = 306) and the Genes-environments and Admixture in Latino Americans (GALA II) study (n = 573). Whole-genome methylation of DNA from WBCs was measured by using the Illumina Infinium HumanMethylation450 BeadChip. Total IgE levels were measured by using the UniCAP 100 system. In PR-GOAL WBC types (ie, neutrophils, eosinophils, basophils, lymphocytes, and monocytes) in peripheral blood were measured by using Coulter Counter techniques. In the GALA II study WBC types were imputed. Multivariable linear regression was used for the analysis of DNA methylation and total IgE levels, which was first conducted separately for each cohort, and then results from the 2 cohorts were combined in a meta-analysis. Results CpG sites in multiple genes, including novel findings and results previously reported in white subjects, were significantly associated with total IgE levels. However, adjustment for WBC types resulted in markedly fewer significant sites. Top findings from this adjusted meta-analysis were in the genes ZFPM1 ( P = 1.5 × 10−12 ), ACOT7 ( P = 2.5 × 10−11 ), and MND1 ( P = 1.4 × 10−9 ). Conclusions In an epigenome-wide association study adjusted for WBC types (including eosinophils), methylation changes in genes enriched in pathways relevant to asthma and immune responses were associated with total IgE levels among Hispanic children.
The principal properties of the tori of gas which surround Seyfert nuclei are discussed. The internal state of the clouds and their size distribution function are examined, and it is shown that the ...Jeans mass scale results in clouds which are individually sufficiently opaque to block out the nucleus, and that the balance of processes which controls their size distribution function also forces the covering factor to be of the order of or greater than unity. Where the gravitational potential is dominated by stars, cloud-cloud collisions keep the molecular clouds close to the equatorial plane. Stirring by stellar processes is never strong enough to compete with collisional losses. The position of the inner edge of the torus is determined by a balance between the inward flow of clouds and the rate at which the nuclear continuum can evaporate them.
Diaper wipes are widely used for sampling residential dust for lead analysis. A thicker type of diaper wipe was incompletely digested and had low recoveries (∼40%) of lead on stock solution spikes ...using existing protocols. A modified protocol was applied to various quality control samples prepared with thicker diaper wipes in 134 batches of field samples. Modifications included a larger reagent volume (20 mL), more concentrated acid (50% HNO3 followed by concentrated HNO3), 3 h on the hot plate, and squeezing wipe residues during filtration. Seventeen batches were reanalyzed using matrix-matched standards. Acceptable lead recoveries were obtained for stock solution spikes (88%) and spikes prepared with leaded dustSRM 2582 (88%), SRM 2589 (96%), and CRMO 14-050 (99%). Matrix-matched calibration standards increased mean lead recoveries by an additional 8%. Our protocol may provide a basis for a standard operational procedure for wipe digestion and analysis. Differences in estimates of dust lead loadings attributable to the type of wipe and to sample preparation and calibration procedures have implications for risk assessment, clearance testing, and comparability of laboratory data. Reconsideration of current protocols for wipe materials, wipe digestion, and judging laboratory performance (including the ELPAT external proficiency testing program for wipes) is warranted.
TOXIC LEAD EXPOSURE IN THE URBAN ROCK DOVE DeMent, Samuel H; Chisolm, J. Julian; Eckhaus, Michael A ...
Journal of wildlife diseases,
04/1987, Volume:
23, Issue:
2
Journal Article
Peer reviewed
Open access
Thirteen adult urban rock doves (Columba livia), 12 captured alive and one found dead, were studied from the Baltimore zoo. The mean concentration of lead in the blood for the 12 live birds was 184.5 ...± 531.2 (range 10.5−1,870 μg/dl). Three of the 13 birds with high measured blood and tissue lead concentrations were found at necropsy with lead shot pellets in their gizzards. Correlations were not found between concentrations of lead in the blood and body weight or hematocrit. Conversely, high correlations were noted between concentrations of lead in the blood and measured liver and kidney concentrations (r = 0.946, P < 0.01; r = 0.993, P < 0.01, respectively). Numbers of intranuclear acid-fast inclusions per 10 consecutive fields (100× oil immersion lens) correlated well with measured kidney lead concentrations (r = 0.990, P < 0.001).
In the study of human populations, much emphasis is placed on the concentration of lead in whole peripheral blood. There is a considerable body of evidence which indicates that this measurement ...reflects recent and current assimilation of lead. While broad ranges in blood lead concentration have been associated with differing risks of toxicity for groups, it is not a precise index of adverse effect per se, even at elevated levels. Within the red blood cell itself there is not a close association between the concentration of lead and such adverse metabolic effects as the increased loss of potassium caused by lead. Above the apparent "threshold zone" of approximately 30-50 μg Pb/100 ml whole blood, equivalent metabolic effects on heme synthesis may be seen over an interval of at least 20 μg Pb/100 ml whole blood. This variation will be examined with particular reference to the interrelationship between the concentrations of lead and protoporphyrin in peripheral blood. The data indicate that limitations in both precision and accuracy of measurement account for a relatively small fraction of the observed variations. Together with other experimental and clinical information, they suggest that concurrent dietary deficiency of iron may be one of the important modifying factors in the responses of subjects with increased lead absorption. It is suggested that suspected adverse effects upon the various organ systems associated with increased lead absorption be measured directly and that the CaEDTA mobilization test for lead should be more fully explored as a measure of the "metabolically active" fraction of the total body lead burden.
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