Background: Both genetic and environmental factors, e.g. early childhood infections, have a role in the pathogenesis of atopic diseases. Objective: To examine simultaneously the strength and possible interactions of two known such factors, IL4 genetics and Helicobacter pylori infection, on the risk of atopy and asthma. Methods: Gene polymorphism analyses and skin prick tests (SPT) were determinedin 245 adult asthmatics and 405 nonasthmatic controls of population-based case-control study. SPTs were used as an indicator of atopy. H. pylori infection was verified by detecting anti-H. pylori IgG antibodies in sera. Results: A significant negative association was seen between the presence H. pylori antibodies and SPT positivity (≧1 positive reactions) in both asthmatics and controls (p = 0.002 and p = 0.025, respectively) but the effect of IL-4 polymorphism (SNP –590C/T) was nonsignificant in both groups (p = 0.071 and p = 0.072, respectively). However, IL4 genetics had an effect on susceptibility to H. pylori: asthmatics carrying the IL4 –590 allele T had a diminished risk to be H. pylori infected (OR 0.485 95%CI 0.287–0.819). This effect was not seen in controls. Logistic regression analysis indicated that H. pylori and IL4 effects on atopy risk are not interdependent. Conclusions: This study showed that the effect of H. pylori infection on atopy risk is stronger than that of IL4 genetics. There is no interaction between these factors on the pathogenesis of atopy suggesting that these factors have distinct immunopathogenetic mechanisms. However, the genetic effect may modify the role of infective agents by effecting on susceptibility to disease.

Background: Many studies have demonstrated a connection between asthma and T-cell cytokine genes, such as genes coding for interleukin-4 (IL4) and IL-13, which are involved in the regulation of the TH1/TH2 balance. The toll-like receptor 4 (TLR4), the principal receptor for bacterial endotoxin, has attracted attention as a potential risk factor for asthma. We examined whether the polymorphisms of the TLR4 (A/G at +896) and IL4 (C/T at –590) showed an epistatic effect on the risk of asthma or atopy. Methods: Gene polymorphism analyses and skin prick tests were performed on asthmatic and nonasthmatic adult subjects of a Finnish population-based case-control study. The phenotype studied was persistent asthma. Results: The results showed that genotypes of neither the TLR4 SNP at +896 nor IL4 SNP at –590 were separately found to be associated with asthma. However, the female carriers of allele G (i.e. genotype AG or GG) of TLR4 and allele T (genotype CT or TT) of IL4 had a significantly increased risk for asthma. No association of these genes and atopy was found. Conclusions: Our results indicate that in females the TLR4 and IL4 genes show an epistatic effect on the risk of asthma. The low LPS-responsive allele G of TLR4 and high IgE production allele T of IL4 were found to be the predisposing combination. However, there was no epistatic effect on the risk of atopy.

Background: Our aim was to observe factors associated with IL13 rs20541 polymorphism and other factors with or without allergic comorbidities such as subject-reported allergic rhinitis (AR) and/or allergic conjunctivitis (AC) symptoms in adult asthmatics. Methods: A population-based sample of Finnish adult asthma patients (n = 1,156) and matched controls (n = 1,792) filled in a questionnaire. Asthma was diagnosed based on a typical history of asthma symptoms and lung function tests. Skin prick tests with 17 aeroallergens and blood tests including analysis of interleukin 13 (IL13) rs20541 (G/A) genotypes were performed for a subsample (n = 193). Results: The proportion of asthmatics reporting AR was 61.9% and reporting AC was 40.7%. After adjustments, the presence of the IL13 rs20541A- allele (OR 3.06, 95% CI 1.42-6.58, p = 0.004) or multisensitization (adjusted OR 4.59, 95% CI 1.48-14.26, p = 0.008) was associated with AR/AC asthma. Nasal polyps and acetylsalicylic acid-exacerbated respiratory disease was also associated with AR/AC asthma. Conclusions: Adult AR/AC asthma could putatively be a phenotype, characterized by the presence of atopic and/or eosinophilic factors and a high prevalence of the IL13 rs20541A- allele. Studies on the mechanisms behind this and in other populations are needed.

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The most common approach for retinal imaging is the eye fundus photography which usually results in RGB images. Recent studies show that the additional spectral information provides useful features for automatic retinal image analysis. The current work extends recent research on the joint segmentation of retinal vasculature, optic disc and macula which often appears in different retinal image analysis tasks. Fully convolutional neural networks are utilized to solve the segmentation problem. It is shown that the network architectures can be effectively modified for the spectral data and the utilization of spectral information provides moderate improvements in retinal image segmentation.