Atopic dermatitis and food sensitization in South African toddlers: Role of fiber and gut microbiota

The pathogenesis of atopic dermatitis (AD) is complex and related to allergic responses and defects in skin barrier function. In common with many atopic diseases, the prevalence of AD has been increasing across the world.1 One of the theories for this increase is increased hygiene and urbanization-related changes in the environment, which can affect the human microbiome.2 Previous studies have found associations between the composition of the early gut microbiome and development of atopic conditions, including AD.3 Although the rate of atopic conditions, including AD and food allergy, is increasing on all continents, the prevalence of these diseases is still lower in African countries.1 This is especially interesting because individuals of African origin who live in Western countries, such as African Americans, are at a higher risk for severe AD.4 This variation places Africa in a special position; studying African populations is necessary not only to find ways to prevent increases of allergy conditions in African countries but also to provide important clues to the causes of this global increasing of allergic conditions. Young children who have developed AD in African communities with a low incidence of atopic disease might be the transitional group. In the current study, we have, for the first time to our knowledge, analyzed the fecal microbiota composition of a group of young black African children aged 12 to 36 months old with and without AD living in the same community in Cape Town, South Africa. Our primary goal was to examine whether toddlers with AD and control toddlers from Cape Town have different microbiomes in terms of bacterial richness and diversity. We also aimed to investigate the differences in the relative abundance for different operational taxonomic units between these 2 groups. In our subgroup analyses, we further tested the effect of multiple environmental factors on the gut microbiome in these children

Knowledge and risk perception of sexually transmitted infections and relevant health care services among high school students in the Platfontein San community, Northern Cape Province, South Africa

Peter Nyasulu,1,2 Mercedes Fredericks,2 Tariro J Basera,2 Sean Broomhead3 1Division of Epidemiology and Biostatistics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa; 2School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa; 3Health Information Systems Program, Waterkloof Ridge, Pretoria, South Africa Background: The historically marginalized Platfontein San youths have a high rate of teenage pregnancies and sexually transmitted infections (STIs). The aim of the study was to assess the knowledge and perception of male and female school-going youths in Platfontein of STIs and HIV/AIDS, and the health care services that are available to them.Participants and methods: A descriptive cross-sectional survey with a sample of 201 learners in grades 6–12 at the !Xunkwesa Combined School in Platfontein was conducted in July 2007. A pretested self-administered questionnaire was used for data collection.Results: The study found that STI knowledge was 70.1% and HIV and AIDS was 11.9%. Perceptions of risk among the learners were uniformly low; 24% for contracting a STI and 26% for HIV. About 59% (n=119) of the respondents were either unaware or not sure of the primary health care (PHC) services within the community. Overall, 65% of the students reported using PHC services while 35% exclusively used traditional healers. Slightly less than half (43%) of the learners acquired information about sexual and reproductive health through the Life Skills curriculum at school.Conclusion: The study highlights the importance of increasing HIV awareness and inculcating sexual and reproductive health into the school curriculum. The study further shows the imperative need to recognize the role of traditional medicine in the health care choices of this community. Traditional value systems need to be incorporated into the way that education and health care is proposed to the community leaders, to increase acceptance and utilization of health services. Keywords: sexually transmitted infections, school-going youths, Platfontein, knowledge, perceptions, San communit

Elucidating the origin of magnetic ordering in ferroelectric BaTiO3-delta thin film via electronic structure modification

With the motive of unraveling the origin of native vacancy induced magnetization in ferroelectric perovskite oxide systems, here we explore the consequences of electronic structure modification in magnetic ordering of oxygen deficient epitaxial BaTiO3-delta thin films. Our adapted methodology employs state-of-the-art experimental approaches viz. photoemission, photo-absorption spectroscopies, magnetometric measurements duly combined with first principles based theoretical methods within the frame work of density functional theory (DFT and DFT+U) calculations. Oxygen vacancy (O-V) is observed leading partial population of Ti 3d (t(2g)), which induces defect state in electronic structure near the Fermi level and reduces the band gap. The oxygen deficient BaTiO2.75 film reveals Mott-Hubbard insulator characteristic, in contrast to the band gap insulating nature of the stoichiometric BaTiO3. The observed magnetic ordering is attributed to the asymmetric distribution of spin polarized charge density in the vicinity of O-V site, which originates unequal magnetic moment values at first and second nearest neighboring Ti sites, respectively. Hereby, we present an exclusive method for maneuvering the band gap and on-site electron correlation energy with consequences on magnetic properties of BaTiO3-delta system, which can open a gateway for designing novel single phase multiferroic system

Molecular IgE sensitization profiles of urban and rural children in South Africa

Item does not contain fulltextBACKGROUND: Allergens can act as disease-triggering factors in atopic dermatitis (AD) patients. The aim of the study was to elucidate the molecular IgE sensitization profile in children with and without AD living in urban and rural areas of South Africa. METHODS: Specific IgE reactivity was assessed in 166 Black South African children aged 9-38 months using a comprehensive panel of microarrayed allergens. According to clinical characterization children fell in four groups, urban AD cases (n = 32), urban controls (non-AD, n = 40), rural cases (n = 49) and rural controls (non-AD, n = 45). RESULTS: IgE reactivity to at least one of the allergens was detected in 94% of urban and 86% of rural AD children. House dust mite (HDM; 81% urban, 74% rural AD) and animal-derived allergens (50% urban, 31% rural AD) were the most frequently recognized respiratory allergens, whereas IgE to pollen allergens was almost absent. Urban AD children showed significantly higher frequency of IgE reactivity (50%) to mouse lipocalin, Mus m 1, than rural AD children (12%). The most frequently recognized food allergens were from egg (63% urban, 43% rural AD), peanut (31% vs 41%), and soybean (22% vs 27%), whereas milk sensitization was rare. α-gal-specific IgE almost exclusively occurred in rural children (AD: 14%, non-AD: 49%). CONCLUSION: Molecular allergy diagnosis detects frequent IgE sensitization to HDM, animal but not pollen allergens and to egg, peanut, and soy, but not milk allergens in African AD children. Urban AD children reacted more often to Mus m 1, whereas α-gal sensitization is more common in rural children likely due to parasite exposure