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Edwards A.M.,The David Hide Asthma and Allergy Research Center
BMJ case reports | Year: 2011

Diffuse cutaneous mastocytosis (DCM) is a rare, severe, variant of cutaneous mastocytosis. The authors report the case of a male infant who developed maculae and maculopapulae on his legs and abdomen when aged 3.5 months, which spread to all body surfaces within weeks. Diagnosis of DCM was made at the age of 6 months when he had developed extensive bullous eruptions, generalised pruritus, flushing and abdominal pain. Treatment was started with oral dimethindine maleate. At the age of 18 months, oral sodium cromoglicate (SCG) was introduced. At the age of 23 months, additional treatment was started with a cutaneous emulsion containing 4% SCG. Continued treatment with oral dimethindine maleate, oral SCG with the dose maintained at 25 mg/kg/day, and SCG 4% cutaneous emulsion applied two to four times daily has resulted in a steady improvement of symptoms and skin appearance. Source

Quraishi B.M.,University of Memphis | Zhang H.,University of Memphis | Everson T.M.,University of South Carolina | Ray M.,University of Memphis | And 8 more authors.
Clinical Epigenetics | Year: 2015

Background: The prevalence of eczema is increasing in industrialized nations. Limited evidence has shown the association of DNA methylation (DNA-M) with eczema. We explored this association at the epigenome-scale to better understand the role of DNA-M. Data from the first generation (F1) of the Isle of Wight (IoW) birth cohort participants and the second generation (F2) were examined in our study. Epigenome-scale DNA methylation of F1 at age 18 years and F2 in cord blood was measured using the Illumina Infinium HumanMethylation450 Beadchip. A total of 307,357 cytosine-phosphate-guanine sites (CpGs) in the F1 generation were screened via recursive random forest (RF) for their potential association with eczema at age 18. Functional enrichment and pathway analysis of resulting genes were carried out using DAVID gene functional classification tool. Log-linear models were performed in F1 to corroborate the identified CpGs. Findings in F1 were further replicated in F2. Results: The recursive RF yielded 140 CpGs, 88 of which showed statistically significant associations with eczema at age 18, corroborated by log-linear models after controlling for false discovery rate (FDR) of 0.05. These CpGs were enriched among many biological pathways, including pathways related to creating transcriptional variety and pathways mechanistically linked to eczema such as cadherins, cell adhesion, gap junctions, tight junctions, melanogenesis, and apoptosis. In the F2 generation, about half of the 83 CpGs identified in F1 showed the same direction of association with eczema risk as in F1, of which two CpGs were significantly associated with eczema risk, cg04850479 of the PROZ gene (risk ratio (RR) = 15.1 in F1, 95 % confidence interval (CI) 1.71, 79.5; RR = 6.82 in F2, 95 % CI 1.52, 30.62) and cg01427769 of the NEU1 gene (RR = 0.13 in F1, 95 % CI 0.03, 0.46; RR = 0.09 in F2, 95 % CI 0.03, 0.36). Conclusions: Via epigenome-scaled analyses using recursive RF followed by log-linear models, we identified 88 CpGs associated with eczema in F1, of which 41 were replicated in F2. Several identified CpGs are located within genes in biological pathways relating to skin barrier integrity, which is central to the pathogenesis of eczema. Novel genes associated with eczema risk were identified (e.g., the PROZ and NEU1 genes). © 2015, Quraishi et al. Source

Yousefi M.,University of South Carolina | Karmaus W.,University of Memphis | Zhang H.,University of South Carolina | Ewart S.,Michigan State University | And 3 more authors.
International Journal of Molecular Epidemiology and Genetics | Year: 2013

To determine whether DNA methylation (DNA-M) of the leptin receptor genotype (LEPR/LEPROT) links gestational smoking and leptin serum levels and BMI later in life, we focused on female offspring, 18 years of age, from the Isle of Wight Birth Cohort (IOWBC). Leptin binds to the leptin receptor encoded by the LEPR/LEPROT genotype. Using general linear models, we tested a two-stage model. First, we investigated whether single nucleotide polymorphisms (SNPs) acting as methylation quantitative trait loci (methQTLs) depending on gestational smoking were related to differentially methylated cytosine-phosphate-guanine (CpG) sites. In stage 2, we tested whether the selected CpG sites, in interaction with other SNPs (modifiable genetic variants, modGV), are associated with serum leptin and BMI (stage 2). Children from the IOWBC were followed from birth to age 18. Information on gestational smoking was gathered upon delivery. SNPs tagging LEPR and LEPROT genes were genotyped. Data on LEPR/LEPROTDNA-M and leptin were obtained from blood samples drawn at age 18; to determine BMI, height and weight were ascertained. Blood samples were provided by 238 girls. Of the 21 CpG sites, interactions between gestational smoking and SNPs were detected for 16 CpGs. Methylation of seven of the 16 CpGs were, in interaction with modGVs, associated with leptin levels at age 18 years. Two CpGs survived a multiple testing penalty and were also associated with BMI. This two-stage model may explain why maternal smoking has a long-term effect on leptin levels and BMI in girls at age 18 years. Source

Venter C.,University of Portsmouth | Venter C.,The David Hide Asthma and Allergy Research Center | Arshad S.H.,The David Hide Asthma and Allergy Research Center | Arshad S.H.,University of Southampton
Pediatric Clinics of North America | Year: 2011

Food allergy (FA) is perceived as a common problem, especially during childhood. Accurate assessment of incidence and prevalence of FA has been difficult to establish, however, due to lack of universally accepted diagnostic criteria. Although many foods are reported to cause IgE-mediated FA, most studies focus on 4 common food groups: cow's milk, hen's egg, peanut/tree nuts, and fish/shellfish. There may be variation in the prevalence of FA in regions of the world and a likely increase in prevalence has been observed in recent decades. This cannot be stated with confidence, however, without the use of consistent methodology and diagnostic criteria. © 2011 Elsevier Inc. Source

Guthikonda K.,University of Memphis | Zhang H.,University of Memphis | Nolan V.G.,University of Memphis | Soto-Ramirez N.,University of Memphis | And 9 more authors.
Clinical Epigenetics | Year: 2014

Background: The prevalence of asthma in girls increases after puberty. Previous studies have detected associations between sex hormones and asthma, as well as between sex hormones and T helper 2 (Th2) asthma-typical immune responses. Therefore, we hypothesized that exogenous or endogenous sex hormone exposure (represented by oral contraceptive pill (OCP) use and early menarche, respectively) are associated with DNA methylation (DNA-M) of the Th2 transcription factor gene, GATA3, in turn affecting the risk of asthma in girls, possibly in interaction with genetic variants. Blood samples were collected from 245 female participants aged 18 years randomly selected for methylation analysis from the Isle of Wight birth cohort, UK. Information on use of OCPs, age at menarche, and concurrent asthma were assessed by questionnaire. Genome-wide DNA-M was determined using the Illumina Infinium HumanMethylation450 beadchip. In a first stage, we tested the interaction between sex hormone exposure and genetic variants on DNA-M of specific cytosine-phosphate-guanine (CpG) sites. In a second stage, we determined whether these CpG sites interact with genetic variants in GATA3 to explain the risk of asthma. Results: Interactions between OCP use and seven single nucleotide polymorphisms (SNPs) of GATA3 were analyzed for 14 CpG sites (stage 1). The interaction between OCP use and SNP rs1269486 was found to be associated with the methylation level of cg17124583 (P = 0.002, false discovery rate (FDR) adjusted P = 0.04). DNA-M of this same CpG site was also influenced by the interaction between age at menarche and rs1269486 (P = 0.0017). In stage 2, we found that cg17124583 modified the association of SNP rs422628 with asthma risk at the age of 18 years (P = 0.006, FDR adjusted P = 0.04). Subjects with genotype AG showed an increase in average risk ratio (RR) from 0.31 (95% CI: 0.10 to 0.8) to 11.65 (95% CI: 1.71 to 79.5) when methylation level increased from 0.02 to 0.12, relative to genotype AA. Conclusion: A two-stage model consisting of genetic variants in the GATA3 gene, OCP use, age at menarche, and DNA-M may explain how sex hormones in women can increase the asthma prevalence after puberty. © 2014, Guthikonda et al.; licensee BioMed Central Ltd. Source

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