not-yet-known not-yet-known not-yet-known unknown Background: We have previously described that 87,6 % of children with juvenile colorectal polyp (JCP) from La Plata Children’s Hospital are sensitized to food allergens. Tissues of JCP are characterized by type 2 inflammation and the abundant presence of active sites of IgE synthesis. Objective: The aim of this work was to study a potential link between polyps and gut microbiota dysbiosis. Methods : We characterized bacterial populations in feces of food allergen-sensitized children with JCP, feces from healthy children and those associated with JCP tissues. Microbial diversity and composition were evaluated using next generation sequencing of the amplified 16S rRNA gene V3-V4 hypervariable region. Results: The principal component analysis applied to β-diversity discriminated well among sample groups. The taxonomic characterization of the bacterial communities in stool samples from food-sensitized children showed a reduced abundance of Bacteroidetes (Bacteroides) and, at the genera and species levels, an increased number of Mediterraneibacter faecis, Prevotella copri, Catenibacterium , and Prevotella hominis , Sutterella wadsworthensis and Phascolarctobacterium A succinatutens compared to feces of healthy children. We found that the microbiome associated with the polyp tissues was enriched in inflammation- and colorectal cancer associated bacteria, including Fusobacterium, Escherichia and Corynebacterium, with elevated levels of Escherichia fergussoni , Akkermansia muciniphila and Enterocloster . Conclusion: Our study highlights differences in bacterial diversity between food sensitized and healthy children’s feces, and that associated with the polyps. This is the first comprehensive description of JCP microbiota in food sensitized patients and may reveal mechanisms of allergic inflammation and polyp formation, underscoring the importance of monitoring for potential malignant lesions.

Mathematical reasoning involves the activation of frontal and parietal lobes, due to the requirement of working memory, attention, and retrieval mechanisms. Efficient activation of different brain networks, as suggested by previous EEG studies, is related to the level of mathematical ability. We performed a paired comparison of mutual information and power spectrum during math calculations against rest in two groups of participants with different levels of mathematical competence, defined as good and bad counters. Results were displayed through planar head diagrams showing EEG derivations as nodes connected by edges representing significant increases or decreases in mutual information. Power spectrum analysis revealed that good counters presented significant cortical activation in delta, theta, beta and gamma frequency bands and strong alpha blocking during math in comparison to rest. Mutual information analysis showed coupling increases involving more edges, which were topographically widespread in subjects with less arithmetical ability. Decreases in mutual information were prominent in good counters in the beta and alpha frequency bands, while bad counters showed both coupling and uncoupling the alpha band. In both arithmetical ability groups, decoupling was prominent in the prefrontal and parietal areas, particularly in the theta, alpha and beta bands, confirming the importance of frontoparietal activity during mathematical reasoning. Our results are in line with the neural efficiency hypothesis and indicate that those with greater mathematical competence present activation of fewer edges in defined cortical areas, whereas those with lower proficiency require the recruitment of additional edges to complete the task.