Characteristics of the Gut Microbiota in Regard to Atopic Dermatitis and Food Allergies of Children.

The gut microbiota plays an important role in maintaining human health, as well as in the development of various pathologies, as indicated by a large amount of research. One of the manifestations of an imbalance in the gut microbiome composition is the appearance of various diseases or immune reactions, in particular, atopic dermatitis (AD) and/or food allergies (FA). In this research, using 16S NGS sequencing, it was found that the gut microbiome of children with food allergies and children with atopic dermatitis can be characterized as having higher inflammatory potential. Both groups exhibited an abundance of representatives from the Pasteurellaceae and Erysipelotrichaceae families, as well as a decrease in the relative number of representatives from the Barnesiellaceae family compared to healthy participants. In the group of participants with food allergies, there was a decrease in the relative number of Desulfovibrionaceae representatives and Bifidobacteriaceae family enrichment in relatively healthy participants. In addition, when comparing this group with patients with atopic dermatitis, it was revealed that a number of representatives of such families as Erysipelotrichaceae, Ruminococcaceae and Sutterellaceae prevailed. This information confirms that AD and FA correlate with changes in the composition of the gut microbiota. Further research is needed to determine the cause-effect connections and the effect of compounds derived from the microbiota on the AD and FA development and progression, as well as to create new probiotic drugs to prevent and modulate immune responses, including at an early age.

Design of a Protocol for Soil-Transmitted Helminths (in Light of the Nematode Toxocara canis) DNA Extraction from Feces by Combining Commercially Available Solutions.

One of the main challenges for the mass introduction of the molecular diagnostics of soil-transmitted helminths (STHs) into clinical practice is the lack of a generally recognized effective method for isolating parasitic DNA from fecal samples. In the present study, we assessed the effects of various pretreatment procedures on the efficiency of removing PCR inhibitors and extracting Toxocara canis DNA from feces. We evaluated the effectiveness of four destructive methods (bead beating, the action of temperature-dependent enzymes, freeze-heat cycles, and incubation in a lysis buffer) on the integrity of T. canis eggs and the efficiency of DNA extraction. Also, we evaluated the effects of prewashes and the use of commercial concentrators on DNA extraction from fecal samples contaminated with T. canis eggs. A bead beating procedure was sufficient to destroy the T. canis eggs, while the effects of enzymes and freeze-heat cycles did not lead to a significant destruction of the eggs or the release of Toxocara DNA. Helminth DNA isolation protocols that do not include a bead beating step are not preferred. The preconcentration of STH eggs from feces using a commercial concentrator and subsequent washing can significantly increase the yield of DNA from STHs and reduce PCR inhibition.