Enhanced Mucosal Antibody Production and Protection against Respiratory Infections Following an Orally Administered Bacterial Extract

Secondary bacterial infections following influenza infection are a pressing problem facing respiratory medicine. Although antibiotic treatment has been highly successful over recent decades, fatalities due to secondary bacterial infections remain one of the leading causes of death associated with influenza. We have assessed whether administration of a bacterial extract alone is sufficient to potentiate immune responses and protect against primary infection with influenza, and secondary infections with either Streptococcus pneumoniae or Klebsiella pneumoniae in mice. We show that oral administration with the bacterial extract, OM-85, leads to a maturation of dendritic cells and B-cells characterized by increases in MHC II, CD86, and CD40, and a reduction in ICOSL. Improved immune responsiveness against influenza virus reduced the threshold of susceptibility to secondary bacterial infections, and thus protected the mice. The protection was associated with enhanced polyclonal B-cell activation and release of antibodies that were effective at neutralizing the virus. Taken together, these data show that oral administration of bacterial extracts provides sufficient mucosal immune stimulation to protect mice against a respiratory tract viral infection and associated sequelae

Comment on ‘New palaeomagnetic result from Vendian red sediments in Cisbaikalia and the problem of the relationship of Siberia and Laurentia in the Vendian’ by S. A. Pisarevsky, R. A. Komissarova and A. N. Khramov

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73333/1/j.0956-540x.2001.01474.x.pd

Gut-derived short-chain fatty acids modulate skin barrier integrity by promoting keratinocyte metabolism and differentiation

Barrier integrity is central to the maintenance of healthy immunological homeostasis. Impaired skin barrier function is linked with enhanced allergen sensitization and the development of diseases such as atopic dermatitis (AD), which can precede the development of other allergic disorders, for example, food allergies and asthma. Epidemiological evidence indicates that children suffering from allergies have lower levels of dietary fibre-derived short-chain fatty acids (SCFA). Using an experimental model of AD-like skin inflammation, we report that a fermentable fibre-rich diet alleviates systemic allergen sensitization and disease severity. The gut-skin axis underpins this phenomenon through SCFA production, particularly butyrate, which strengthens skin barrier function by altering mitochondrial metabolism of epidermal keratinocytes and the production of key structural components. Our results demonstrate that dietary fibre and SCFA improve epidermal barrier integrity, ultimately limiting early allergen sensitization and disease development. The Graphical Abstract was designed using Servier Medical Art images (https://smart.servier.com). [Image: see text

A palaeoecological model for the late Mesoproterozoic – early Neoproterozoic Atar/El Mreïti Group, Taoudeni Basin, Mauritania, northwestern Africa

Reconstructing the spatial distribution of early eukaryotes in palaeoenvironments through Proterozoic sedimentary basins provides important information about their palaeocology and taphonomic conditions. Here, we combine the geological context and a reconstruction of palaeoenvironmental redox conditions (using iron speciation) with quantitative analysis of microfossil assemblages (eukaryotes and incertae sedis), to provide the first palaeoecological model for the Atar/El Mreïti Group of the Taoudeni Basin. Our model suggests that in the late Mesoproterozoic – early Neoproterozoic, the availability of both molecular oxygen and nutrients controlled eukaryotic diversity, higher in oxic shallow marginal marine environments, while coccoidal colonies and benthic microbial mats dominated respectively in anoxic iron-rich and euxinic waters during marine highstands or away from shore where eukaryotes are lower or absent

Engineering access to higher education through higher education fairs

Text from van Zanten A., Legavre A. “Engineering access to higher education through higher education fairs”, in Goastellec G., Picard F. (ed.) The Roles of Higher Education and Research in the Fabric of Societies, Leuven, Sense Publishers, 2014 (in press). Transition to higher education is a major social process. This transition has been mostly studied by French sociologists of education and higher education from perspectives focusing predominantly on the role of the socio-economic status, academic profiles and different tracks followed by secondary school students (Merle 1996, Duru-Bellat and Kieffer 2008, Convert 2010), and, to a lesser extent, on the types of secondary schools attended (Duru-Bellat and Mingat 1998, Nakhili 2005) and the local higher education provision (Berthet et al. 2010, Orange 2013). Although these structural determinants play a major role in explaining significant regularities, they provide more powerful explanations for individuals representing the extremes of the different variables considered, leaving room for the influence of other major factors for those students in intermediate situations. In addition, even in the case of students occupying extreme positions, structural perspectives better explain the distribution of students between different higher education tracks than they do between institutions and disciplines. In this chapter, we adopt a perspective that we see as complementary to and interacting with the perspective centred on structural determinants by focusing on the role of the devices that mediate the exchanges between students and higher education institutions, and more specifically on one device: higher education fairs. Our purpose in doing so is not only to document how these various devices frame, in ways that remain largely unexplored by researchers, exchanges between providers and consumers of higher education but also to point out – and further explore in future publications – how these devices, and the specific features of fairs, contribute to the reproduction and transformation of educational inequalities in access to higher education (Benninghoff et al. 2012)

Toward safer thanatopraxy cares: formaldehyde-releasers use.

Human cadavers constitute very useful educational tools to teach anatomy in medical scholarship and related disciplines such as physiology, for example. However, as biological material, human body is subjected to decay. Thanatopraxy cares such as embalming have been developed to slow down and inhibit this decay, but the formula used for the preservation fluids are mainly formaldehyde (FA)-based. Very recently, other formulas were developed in order to replace FA, and to avoid its toxicity leading to important environmental and professional exposure concerns. However, these alternative FA-free fluids are still not validated or commercialized, and their efficiency is still under discussion. In this context, the use of FA-releasing substances, already used in the cosmetics industry, may offer interesting alternatives in order to reduce professional exposures to FA. Simultaneously, the preservation of the body is still guaranteed by FA generated over time from FA-releasers. The aim of this review is to revaluate the use of FA in thanatopraxy cares, to present its benefits and disadvantages, and finally to propose an alternative to reduce FA professional exposure during thanatopraxy cares thanks to FA-releasers use

Recent advances in food allergy

Food allergy is a public health issue that has significantly increased worldwide in the past decade, affecting consumers’ quality of life and making increasing demands on health service resources. Despite recent advances in many areas of diagnosis and treatment, our general knowledge of the basic mechanisms of the disease remain limited i.e., not at pace with the exponential number of new cases and the explosion of new technologies. Many important key questions remain: What defines a major allergen? Why do some individuals develop food allergies and others do not? Which are the environmental factors? Could the environmental factors be monitored through epigenetics or modified by changes in the microbiome? Can tolerance to food be induced? Why are some foods more likely to trigger allergies than others? Does the route and timing of exposure have any role on sensitization? These and many other related questions remain unanswered. In this short review some of these topics are addressed in the light of recent advances in the area

Associations between infant fungal and bacterial dysbiosis and childhood atopic wheeze in a nonindustrialized setting.

BACKGROUND: Asthma is the most prevalent chronic disease of childhood. Recently, we identified a critical window early in the life of both mice and Canadian infants during which gut microbial changes (dysbiosis) affect asthma development. Given geographic differences in human gut microbiota worldwide, we studied the effects of gut microbial dysbiosis on atopic wheeze in a population living in a distinct developing world environment. OBJECTIVE: We sought to determine whether microbial alterations in early infancy are associated with the development of atopic wheeze in a nonindustrialized setting. METHODS: We conducted a case-control study nested within a birth cohort from rural Ecuador in which we identified 27 children with atopic wheeze and 70 healthy control subjects at 5 years of age. We analyzed bacterial and eukaryotic gut microbiota in stool samples collected at 3 months of age using 16S and 18S sequencing. Bacterial metagenomes were predicted from 16S rRNA data by using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States and categorized by function with Kyoto Encyclopedia of Genes and Genomes ontology. Concentrations of fecal short-chain fatty acids were determined by using gas chromatography. RESULTS: As previously observed in Canadian infants, microbial dysbiosis at 3 months of age was associated with later development of atopic wheeze. However, the dysbiosis in Ecuadorian babies involved different bacterial taxa, was more pronounced, and also involved several fungal taxa. Predicted metagenomic analysis emphasized significant dysbiosis-associated differences in genes involved in carbohydrate and taurine metabolism. Levels of the fecal short-chain fatty acids acetate and caproate were reduced and increased, respectively, in the 3-month stool samples of children who went on to have atopic wheeze. CONCLUSIONS: Our findings support the importance of fungal and bacterial microbiota during the first 100 days of life on the development of atopic wheeze and provide additional support for considering modulation of the gut microbiome as a primary asthma prevention strategy

Development of a cDNA microarray for the measurement of gene expression in the sheep scab mite Psoroptes ovis

Background: Sheep scab is caused by the ectoparasitic mite Psoroptes ovis which initiates a profound cutaneous inflammatory response, leading to the development of the skin lesions which are characteristic of the disease. Existing control strategies rely upon injectable endectocides and acaricidal dips but concerns over residues, eco-toxicity and the development of acaricide resistance limit the sustainability of this approach. In order to identify alternative means of disease control, a deeper understanding of both the parasite and its interaction with the host are required. Methods: Herein we describe the development and utilisation of an annotated P. ovis cDNA microarray containing 3,456 elements for the measurement of gene expression in this economically important ectoparasite. The array consists of 981 P. ovis EST sequences printed in triplicate along with 513 control elements. Array performance was validated through the analysis of gene expression differences between fed and starved P. ovis mites. Results: Sequences represented on the array include homologues of major house dust mite allergens and tick salivary proteins, along with factors potentially involved in mite reproduction and xenobiotic metabolism. In order to validate the performance of this unique resource under biological conditions we used the array to analyse gene expression differences between fed and starved P. ovis mites. These analyses identified a number of house dust mite allergen homologues up-regulated in fed mites and P. ovis transcripts involved in stress responses, autophagy and chemosensory perception up-regulated in starved mites. Conclusion: The P. ovis cDNA microarray described here has been shown to be both robust and reproducible and will enable future studies to analyse gene expression in this important ectoparasite